Patent ID: 12195308

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

Working Machine

FIG.1is a sideview of a crane100serving as a working machine according to the embodiments of the present invention. As shown inFIG.1, the crane100includes: a lower traveling body1serving as a base body; an upper slewing body2slewably supported on the lower traveling body1; a lattice boom3; a jib4; a mast5; a rear strut6; and a front strut7. The upper slewing body2has a rear portion on which a counterweight2A for adjusting the balance of the crane100is mounted, and a front end on which a cab2B serving as an operator seat device is mounted.

The lattice boom3has a lower end constituting a boom foot8, and is supported on a slewing frame of the upper slewing body2rotatably about the lower end in a raising and lowering direction. The lattice boom3includes a plurality of lattice structures coupled to each other. The lattice structures include a first boom member31, a second boom member32, a third boom member33, and a fourth boom member34arranged in this order from a proximal end of the lattice boom.

The first boom member31serves as a proximal boom member and has a proximal end including the boom foot8and a distal end opposite the proximal end. The boom foot8is connected to a front portion of the upper slewing body2rotatably in the raising and lowering direction.

The second to fourth boom members32,33,34are arranged in this order from a position closer to the first boom member31, and the boom members adjacent to each other in the arrangement direction (i.e., a longitudinal direction of the lattice boom3) are detachably couplable to each other. Each of the second and third boom members32,33serves as an intermediate boom member, and has a proximal end detachably connectable to the boom member adjacent to the proximal end, and a distal end detachably connectable to the boom member adjacent to the distal end. The fourth boom member34serves as a distal boom member, and has a proximal end detachably connectable to the distal end of the third boom member33, and a distal end also serving as the distal end of the lattice boom3opposite the proximal end.

The jib4is rotatably connected to the distal end of the lattice boom3, that is, rotatably connected to the distal end of the fourth boom member34. The mast5, the rear strut6, and the front strut7are members for rotating the jib4.

The mast5has a proximal end supported on the upper slewing body2rotatably in the same direction as the raising and lowering direction of the boom3, and a distal end opposite the proximal end. The distal end is connected to the distal end of the boom3via a pair of left and right boom guide lines9.

The rear strut6and the front strut7are rotatably supported at the distal end of the lattice boom3. The rear strut6is held in a posture extending out from the distal end of the lattice boom3toward a boom raising direction (on a left side inFIG.1) by a pair of left and right backstops10and a link11. The front strut7is connected to the jib4via a pair of left and right jib guy lines12rotatably in cooperation with (integrally with) the jib4.

A plurality of winches are mounted on the upper slewing body2. The winches include a boom raising and lowering winch13, a jib raising and lowering winch14, a main winch15, and an auxiliary winch16.

The boom raising and lowering winch13winds up and out a boon raising and lowering rope17to rotate the mast5, thereby raising and lowering the lattice boom3. The boom raising and lowering rope17extends over sheave blocks18,19respectively provided at a rotational end of the mast5and a rear end of the upper slewing body2.

The jib raising and lowering winch14winds up and out a jib raising and lowering rope22extending between the rear strut6and the front strut7to rotate the front strut7, thereby raising and lowering the jib4. The jib raising and lowering rope22is supported on a guide sheave23provided at an intermediate portion of the rear strut6in a longitudinal direction thereof, and extends over sheave blocks24,25respectively provided at a rotational end of the rear strut6and a rotational end of the front strut7.

The main winch15performs hoisting and lowering of a hanged load to be hanged from a distal end of the jib4via a main rope20, and the auxiliary winch16performs hoisting and lowering of a hanged load to be hanged from the distal end of the jib4via an auxiliary rope21.

In the crane100described heretofore, each of the first to fourth boom members31to34composing the lattice boom3serves as a lattice structure basically having a common configuration. Under the circumstances, a basic configuration of each of the second boom member32and the third boom member33adjacent thereto representatively among the first to fourth main members31to34, and a configuration for detachably coupling the second boom member32and the third boom member33to each other will be described with reference to the drawings.

Lattice Structure According to First Embodiment

FIG.2is a perspective view of a lattice structure33(third boom member33) according to a first embodiment of the present invention and another lattice structure32(second boom member32) coupled to the lattice structure33. These lattice structures32,33form a lattice structure coupled body.FIG.3is a perspective view of one of the lattice structures32,33inFIG.2.

As shown inFIGS.2and3, each of the lattice structures32,33includes four main members50, a plurality of connectors, a plurality of diagonal members60, and a plurality of reinforcement parts40. The lattice structure32and the lattice structure33have the same configuration.

Main Member

Each of the four main members50is a linearly extending pipe (main pipe), and has one end in a longitudinal direction D (axial direction D) thereof and another end opposite the one end in the longitudinal direction D. The four main members50are arranged at intervals in a direction perpendicular to a longitudinal direction of the lattice structure (a radial direction of the main member50). Each of the main members50is arranged so as to extend along the longitudinal direction of the lattice boom3, that is, along the longitudinal direction of each of the lattice structures32,33. Specifically, each of the main members50is arranged in a posture parallel to the longitudinal direction of each of the lattice structures32,33.

The four main members50include a first main member51, a second main member52, a third main member53, and a fourth main member54. The first to fourth main members50are arranged, in this order, at positions corresponding to four vertices of a rectangular shape (specifically, e.g., square) when the lattice structure is viewed in the longitudinal direction thereof. In each of the lattice structures32,33, the four main members50are arranged in parallel to one another, but the arrangement thereof is not limited thereto.

Connector

FIG.4is an enlarged view of a portion in a framed box IV inFIG.2.FIG.5is an enlarged view of a portion in a framed box V inFIG.2. As shown inFIG.2toFIG.5, each of the connectors is connected to one of the one end and the another end of each of the four main members50. Specifically, one of a female connector and a male connector is connected to the one end (left end inFIGS.2,3) of each of the four main members50, and the other of the female connector and the male connector is connected to the another end (right end inFIGS.2,3) of each of the four main members50.

In the specific examples shown inFIG.4andFIG.5, the first main member51has one end to which a first female connector71A is connected, and another end to which a first male connector71B is connected. The second main member52has one end to which a second female connector72A is connected, and another end to which a second male connector72B is connected. The third main member53has one end to which a third female connecter71A having the same shape as the first connector71A is connected, and another end to which a third male connector71B having the same shape as the first connector71B is connected. The fourth main member54has one end to which a fourth female connecter72A having the same shape as the second connector72A is connected, and another end to which a fourth male connector72B having the same shape as the second connector72B is connected.

As shown inFIG.3, central axes L of pin insertion holes (axial directions L of pins) of the first connectors71A,71B, those of the second connectors72A,72B, those of the third connectors71A,71B, and those of the fourth connectors72A,72B are parallel to one another.

As shown inFIG.5, the female connector71A and the male connector71B are rotatably connected to each other by a pin90. These connectors71A,71B compose a coupling unit71for the adjacent lattice structures32,33. Each of the connectors71A,71B has an insertion hole90hin which the pin90is inserted. The connector71A has a main member joint73for joining the main member50thereto and a diagonal member joint74for joining the diagonal member60thereto. Similarly, the connector71B has a main member joint73for joining the main member50thereto and a diagonal member joint74for joining the diagonal member60thereto.

In the embodiment, as shown inFIG.5, a plane parallel to the longitudinal direction of the main member50connected to the connector71A and the longitudinal direction of the diagonal member60connected to the connector71A, and a plane parallel to the longitudinal direction of the main member50connected to the connector71B and the longitudinal direction of the diagonal member60connected to the connector71B are parallel to each other and perpendicular to the axial direction L of the pin90(central axis L of the insertion hole90h).

As shown inFIG.4, the female connector72A and the male connector72B are rotatably connected to each other by a pin90. These connectors72A,72B compose a coupling unit72for the adjacent lattice structures32,33. Each of the connectors72A,72B has an insertion hole90hin which the pin90is inserted. The connector72A has a main member joint73for joining the main member50thereto and a diagonal member joint74for joining the diagonal member60thereto. Similarly, the connector72B has a main member joint73for joining the main member50thereto and a diagonal member joint74for joining the diagonal member60thereto.

In the embodiment, as shown inFIG.4, a plane parallel to the longitudinal direction of the main member50connected to the connector72A and the longitudinal direction of the diagonal member60connected to the connector72A, and a plane parallel to the longitudinal direction of the main member50connected to the connector72B and the longitudinal direction of the diagonal member60connected to the connector72B are parallel to each other and parallel to the axial direction L of the pin90(central axis L of the insertion hole90h).

In the embodiment, each of the connectors has only the single main member joint73and the single diagonal member joint74.

Diagonal Member

Each of the diagonal members60is a pipe (diagonal pipe) linearly extending so as to be inclined with respect to the longitudinal direction of the lattice structure, and has one end in a longitudinal direction (axial direction) thereof and another end opposite the one end in the longitudinal direction. Each diagonal member60connects two adjacent main members50among the four main members50with each other.

Specifically, the diagonal members60include, for example, a plurality of first diagonal members60connecting the first main member51and the second main member52with each other. The first diagonal members60connect the first main member51and the second main member52with each other in a zigzag manner. The diagonal members60further include a plurality of second diagonal members60connecting the third main member53and the fourth main member54with each other. The second diagonal members60connect the third main member53and the fourth main member54with each other in a zigzag manner. Similarly, a part of the diagonal members60among the diagonal members60connects the second and third main members52,53with each other, and another part of the diagonal members60among the diagonal members60connects the fourth and first main members54,51with each other.

Nearest Diagonal Member

In the lattice structure according to the embodiment, the diagonal members60include four nearest diagonal members601to604located near the one end (left end inFIG.3) of the lattice structure in the longitudinal direction thereof.

The nearest diagonal member601(serving as an exemplary first nearest diagonal member) is the diagonal member60located nearest to the first connector71A among the first diagonal members60connecting the first main member51and the second main member52with each other. The nearest diagonal member601has one end connected to the first connector71A and another end connected to the second main member52. In this way, the nearest diagonal member601connects the first main member51and the second main member52with each other. The nearest diagonal member601is inclined in a direction D1at an angle to the longitudinal direction of the lattice structure so that a distance between the one end of the nearest diagonal member601and the first connector71A is shorter than a distance between the another end of the nearest diagonal member601and the second connector72A.

The nearest diagonal member602is a diagonal member60located nearest to the second connector72A among the diagonal members60connecting the second main member52and the third main member53with each other. The nearest diagonal member602has one end connected to the second connector72A and another end connected to the third main member53. In this way, the nearest diagonal member602connects the second main member52and the third main member53with each other. The nearest diagonal member602is inclined in a direction D2at an angle to the longitudinal direction of the lattice structure so that a distance between the one end of the nearest diagonal member602and the second connector72A is shorter than a distance between the another end of the nearest diagonal member602and the third connector71A.

The nearest diagonal member603(serving as an exemplary second nearest diagonal member) is a diagonal member60located nearest to the third connector71A among the second diagonal members60connecting the third main member53and the fourth main member54with each other. The nearest diagonal member603has one end connected to the third connector71A and another end connected to the fourth main member54. In this way, the nearest diagonal member603connects the third main member53and the fourth main member54with each other. The nearest diagonal member603is inclined in a direction D3at an angle to the longitudinal direction of the lattice structure so that a distance between the one end of the nearest diagonal member603and the third connector71A is shorter than a distance between the another end of the nearest diagonal member603and the fourth connector72A.

The nearest diagonal member604is a diagonal member60located nearest to the fourth connector72A among the diagonal members60connecting the fourth main member54and the first main member51with each other. The nearest diagonal member604has one end connected to the fourth connector72A and another end connected to the first main member51. In this way, the nearest diagonal member604connects the fourth main member54and the first main member51with each other. The nearest diagonal member604is inclined in a direction D4at an angle to the longitudinal direction of the lattice structure so that a distance between the one end of the nearest diagonal member604and the fourth connector72A is shorter than a distance between the another end of the nearest diagonal member604and the first connector71A.

Similarly, four nearest diagonal members, like the four nearest diagonal members601to604, are arranged near another end of the lattice structure in the longitudinal direction thereof as well.

Reinforcement Part

In the embodiment, each of the reinforcement parts40is a linearly extending pipe (reinforcement pipe). The reinforcement parts40include two reinforcement parts40, i.e., a first reinforcement part40and a second reinforcement part40.

The first reinforcement part40has one end42and another end41in a longitudinal direction (axial direction) thereof. The one end42of the first reinforcement part40is connected to the nearest diagonal member601and the another end41of the first reinforcement part40is connected to the second main member52. The first reinforcement part40extends from the nearest diagonal member601to the second main member52in the longitudinal direction thereof for connecting the nearest diagonal member601and the second main member52with each other. Specifically, the longitudinal direction of the first reinforcement part40indicates a direction (exemplary first specific direction) perpendicular to the longitudinal direction of the lattice structure. The first reinforcement part40is arranged in a posture extending in a direction perpendicular to the central axis L of the pin insertion hole (axial direction L of the pin) of the second connector72A and intersecting the longitudinal direction of the second main member52. More specifically, the first reinforcement part40is arranged in a posture extending in a direction perpendicular to the central axis L of the pin insertion hole (axial direction L of the pin) of the second connector72A and perpendicular to the longitudinal direction of the second main member52. The another end41of the first reinforcement part40is connected to the second main member52at a position in a portion of the second main member52that is adjacent to the second connector72A.

The second reinforcement part40has one end42and another end41in a longitudinal direction (axial direction) thereof. The one end42of the second reinforcement part40is connected to the nearest diagonal member603and the another end41of the second reinforcement part40is connected to the fourth main member54. The second reinforcement part40extends from the nearest diagonal member603to the fourth main member54in the longitudinal direction thereof for connecting the nearest diagonal member603and the fourth main member54with each other. Specifically, the longitudinal direction of the second reinforcement part40indicates a direction (exemplary second specific direction) perpendicular to the longitudinal direction of the lattice structure. The second reinforcement part40is arranged in a posture extending in a direction perpendicular to the central axis L of the pin insertion hole (axial direction L of the pin) of the fourth connector72A and intersecting the longitudinal direction of the fourth main member54. More specifically, the second reinforcement part40is arranged in a posture extending in a direction perpendicular to the central axis L of the pin insertion hole (axial direction L of the pin) of the fourth connector72A and perpendicular to the longitudinal direction of the fourth main member54. The another end41of the second reinforcement part40is connected to the fourth main member54at a position in a portion of the fourth main member54that is adjacent to the fourth connector72A.

The lattice structure according to the embodiment where the one end42of the first reinforcement part40is connected to the nearest diagonal member601as described above eliminates the need to arrange the end of the first reinforcement part40between the end of the nearest diagonal member601and the first connector71A. Accordingly, the end of the nearest diagonal member601can be nearer to the first connector71A. This configuration, even including the first reinforcement part40, can suppress an increase in the distance between the ends of the two diagonal members60, i.e., the distance between the end of the nearest diagonal member601of the lattice structure32and the end of the nearest diagonal member601of the lattice structure33, as shown inFIG.5.

In the embodiment, the one end of the nearest diagonal member601is connected to the first connector71A and the another end of the nearest diagonal member601is connected to the second main member52so that the nearest diagonal member601connects the first main member51and the second main member52with each other. Moreover, the one end of the nearest diagonal member603is connected to the third connector71A and the another end of the nearest diagonal member603is connected to the fourth main member54so that the nearest diagonal member603connects the third main member53and the fourth main member54with each other.

In this aspect, an ideal lattice configuration is attainable in the coupling unit71of the lattice structure. This configuration can consequently suppress lowering in the stiffness of the lattice structure in the coupling unit71and therearound.

In the embodiment, the longitudinal direction of the first reinforcement part40is perpendicular to the longitudinal direction of the lattice structure, and the longitudinal direction of the second reinforcement part40is perpendicular to the longitudinal direction of the lattice structure.

In this aspect, each of the longitudinal direction of the first reinforcement part40and the longitudinal direction of the second reinforcement part40is perpendicular to the longitudinal direction of the lattice structure, and approximates to a direction in which the buckling deformation of the lattice structure may occur. Accordingly, the buckling strength is further effectively improved.

In the embodiment, the first and second main members51,52respectively disposed, among the four vertices of the quadrangular shape, at positions corresponding to two adjacent vertices are supported by the nearest diagonal member601and the first reinforcement part40, and the third and fourth main members53,54respectively disposed at positions corresponding to remaining two vertices among the four vertices are supported by the nearest diagonal member603and the second reinforcement part40. Accordingly, the portions of the lattice structure corresponding to the respective opposite sides of the quadrangular shape thereof are reinforced in a good balance.

Furthermore, in the embodiment, the longitudinal direction of the reinforcement part40is perpendicular to the axial direction L of the pin90(central axis L of the pin insertion hole of the connector). Thus, the reinforcement part40can effectively improve the buckling strength. Specifically, when the boom3receives a compressive load in a longitudinal direction thereof, the main member50of the lattice structure rotates about the pin90relative to the main member50of the another lattice structure in the coupling unit for coupling the lattice structure and the another lattice structure to each other. Hence, the buckling deformation is likely to occur in the coupling unit71and therearound. In the embodiment, the reinforcement part40connects the nearest diagonal member601(603) and the main member52(54) with each other so that the longitudinal direction of the reinforcement part is perpendicular to the axial direction of the pin90. The reinforcement part40arranged in the aforementioned manner can effectively suppress such deformation of the main member50of the lattice structure as to rotate about the pin90relative to the main member50of the another lattice structure when the boom3receives the compressive load. Consequently, the buckling deformation is effectively suppressed.

Lattice Structure According to Second Embodiment

FIG.6is a perspective view of a lattice structure33according to a second embodiment of the present invention, and another lattice structure32coupled to the lattice structure33.FIG.7is a perspective view of one of the lattice structures32,33inFIG.6.

In the second embodiment shown inFIG.6andFIG.7, each of the lattice structures32,33includes four main members50, a plurality of connectors, a plurality of diagonal members60, and a plurality of reinforcement parts40. The lattice structure32and the lattice structure33have the same configuration. Specifically, a basic configuration of the lattice structure according to the second embodiment is similar to that in the first embodiment.

FIG.8is an enlarged view of a portion in a framed box VIII inFIG.6.FIG.9is an enlarged view of a portion in a framed box IX inFIG.6.FIG.10shows a backside of the portion shown inFIG.9.

Each of the four main members50is a linearly extending pipe (main pipe) in the second embodiment as well. As shown inFIG.6toFIG.10, each of the connectors is connected to one of one end and another end of each of the four main members50. Specifically, one of a female connector and a male connector is connected to the one end (left end inFIGS.6,7) of each of the four main members50, and the other of the female connector and the male connector is connected to the another end (right end inFIGS.6,7) of each of the four main members50.

In the specific examples shown inFIG.8toFIG.10, a first main member51has one end to which a first female connector81A is connected, and another end to which a first male connector81B is connected. A second main member52has one end to which a second female connector82A is connected, and another end to which a second male connector82B is connected. A third main member53has one end to which a third female connector81A having the same shape as the first connector81A is connected, and another end to which a third male connector81B having the same shape as the first connector81B is connected. A fourth main member54has one end to which a fourth female connecter82A having the same shape as the second connector82A is connected, and another end to which a fourth male connector82B having the same shape as the second connector82B is connected.

As shown inFIG.7, central axes L of pin insertion holes (axial directions L of pins) of the first connectors81A,81B, those of the second connectors82A,82B, those of the third connectors81A,81B, and those of the fourth connectors82A,82B are parallel to one another.

As shown inFIG.9andFIG.10, the female connector81A and the male connector81B are rotatably connected to each other by a pin90. These connectors81A,81B compose a coupling unit81for the adjacent lattice structures32,33. Each of the connectors81A,81B has an insertion hole90hin which the pin90is inserted. The connector81A has a main member joint83for joining the main member50thereto and two diagonal member joints84for respectively joining corresponding two diagonal members60thereto. Similarly, the connector81B has a main member joint83for joining the main member50thereto and two diagonal member joints84for respectively joining corresponding two diagonal members60thereto.

In the embodiment, as shown inFIG.9andFIG.10, a plane parallel to a longitudinal direction D of the main member50connected to the connector81A and a longitudinal direction D21of one of the diagonal members60connected to the connector81A, and a plane parallel to the longitudinal direction D of the main member50connected to the connector81B and a longitudinal direction D31of the one of the diagonal members60connected to the connector81B are parallel to each other and perpendicular to the axial direction L of the pin90(central axis L of the insertion hole90h).

Besides, a plane parallel to the longitudinal direction D of the main member50connected to the connector81A and a longitudinal direction D22of the other of the diagonal members60connected to the connector81A, and a plane parallel to the longitudinal direction D of the main member50connected to the connector81B and a longitudinal direction D32of the other of the diagonal members60connected to the connector81B are parallel to each other and parallel to the axial direction L of the pin90(central axis L of the insertion hole90h).

As shown inFIG.8, the female connector82A and the male connector82B are rotatably connected to each other by a pin90. These connectors82A,82B compose a coupling unit82for the adjacent lattice structures32,33. Each of the connectors82A,82B has an insertion hole90hin which the pin90is inserted. The connector82A has a main member joint83for joining the main member50thereto while having no diagonal member joint for joining the diagonal members60thereto. Similarly, the connector82B has a main member joint83for joining the main member50thereto while having no diagonal member joint for joining the diagonal members60thereto. In other words, only the main member50is connected to each of the female connector82A and the male connector82B.

Diagonal Member

Each of the diagonal members60is a pipe (diagonal pipe) linearly extending so as to be inclined with respect to the longitudinal direction of the lattice structure for connecting two adjacent main members50among the four main members50with each other in the second embodiment as well. Specifically, for instance, the diagonal members include a plurality of first diagonal members60each connecting the first main member51and the second main member52with each other. The first diagonal members60connect the first main member51and the second main member52with each other in a zigzag manner. Similarly, the diagonal members include a plurality of second diagonal members60each connecting the third main member53and the fourth main member54with each other. The second diagonal members60connect the third main member53and the fourth main member54with each other in a zigzag manner.

Nearest Diagonal Member

The diagonal members60in the second embodiment include four nearest diagonal members601to604located near the one end (left end inFIG.3) of the lattice structure in the longitudinal direction thereof as well.

As shown inFIG.6andFIG.7, the nearest diagonal member601(serving as an exemplary first nearest diagonal member) is a diagonal member60located nearest to the first connector81A among the first diagonal members60connecting the first main member51and the second main member52with each other. The nearest diagonal member601has one end connected to the first connector81A and another end connected to the second main member52. In this way, the nearest diagonal member601connects the first main member51and the second main member52with each other. As shown inFIG.7, the nearest diagonal member601is inclined in the direction D21at an angle to the longitudinal direction of the lattice structure so that a distance between the one end of the nearest diagonal member601and the first connector81A is shorter than a distance between the another end of the nearest diagonal member601and the second connector82A.

The nearest diagonal member602is a diagonal member60located nearest to the second connector82A among the diagonal members60connecting the second main member52and the third main member53with each other. The nearest diagonal member602has one end connected to the third connector81A and another end connected to the second main member52. In this way, the nearest diagonal member602connects the second main member52and the third main member53with each other. The nearest diagonal member602is inclined in the direction D22at an angle to the longitudinal direction of the lattice structure so that a distance between the one end of the nearest diagonal member602and the second connector82A is longer than a distance between the another end of the nearest diagonal member602and the third connector81A.

The nearest diagonal member603(serving as an exemplary second nearest diagonal member) is a diagonal member60located nearest to the third connector81A among the second diagonal members60connecting the third main member53and the fourth main member54with each other. The nearest diagonal member603has one end connected to the third connector81A and another end connected to the fourth main member54. In this way, the nearest diagonal member603connects the third main member53and the fourth main member54with each other. The nearest diagonal member603is inclined in a direction D23at an angle to the longitudinal direction of the lattice structure so that a distance between the one end of the nearest diagonal member603and the third connector81A is shorter than a distance between the another end of the nearest diagonal member603and the fourth connector82A.

The nearest diagonal member604is a diagonal member60located nearest to the fourth connector82A among the diagonal members60connecting the fourth main member54and the first main member51with each other. The nearest diagonal member604has one end connected to the first connector81A and another end connected to the fourth main member54. In this way, the nearest diagonal member604connects the fourth main member54and the first main member51with each other. The nearest diagonal member604is inclined in a direction D24at an angle to the longitudinal direction of the lattice structure so that a distance between the one end of the nearest diagonal member604and the fourth connector82A is longer than a distance between the another end of the nearest diagonal member604and the first connector81A.

Similarly, four nearest diagonal members, like the four nearest diagonal members601to604, are arranged near another end of the lattice structure in the longitudinal direction thereof as well.

Reinforcement Part

Each of the reinforcement parts40is a linearly extending pipe (reinforcement pipe) in the second embodiment as well. Further, the reinforcement parts40include two reinforcement parts40, i.e., a first reinforcement part40and a second reinforcement part40as well.

The first reinforcement part40has one end42and another end41in a longitudinal direction (axial direction) thereof. The one end42of the first reinforcement part40is connected to the nearest diagonal member601and the another end41of the first reinforcement part40is connected to the second main member52. The first reinforcement part40extends from the nearest diagonal member601to the second main member52in the longitudinal direction (exemplary first specific direction) thereof for connecting the nearest diagonal member601and the second main member52with each other. Specifically, the longitudinal direction of the first reinforcement part40is perpendicular to the longitudinal direction of the lattice structure. The first reinforcement part40is arranged in a posture extending in a direction perpendicular to the central axis L of the pin insertion hole (axial direction L of the pin) of the second connector82A and intersecting the longitudinal direction of the second main member52. More specifically, the first reinforcement part40is arranged in a posture extending in a direction perpendicular to the central axis L of the pin insertion hole (axial direction L of the pin) of the second connector82A and perpendicular to the longitudinal direction of the second main member52. The another end41of the first reinforcement part40is connected to the second main member52at a position in a portion of the second main member52that is adjacent to the second connector82A.

The second reinforcement part40has one end42and another end41in a longitudinal direction (axial direction) thereof. The one end42of the second reinforcement part40is connected to the nearest diagonal member603and the another end41of the second reinforcement part40is connected to the fourth main member54. The second reinforcement part40extends from the nearest diagonal member603to the fourth main member54in the longitudinal direction (exemplary second specific direction) thereof for connecting the nearest diagonal member603and the fourth main member54with each other. Specifically, the second reinforcement part40is arranged in a posture extending in a direction perpendicular to the longitudinal direction of the lattice structure. The second reinforcement part40is arranged in a posture extending in a direction perpendicular to the central axis L of the pin insertion hole (axial direction L of the pin) of the fourth connector82A and intersecting the longitudinal direction of the fourth main member54. More specifically, the second reinforcement part40is arranged in a posture extending in a direction perpendicular to the central axis L of the pin insertion hole (axial direction L of the pin) of the fourth connector82A and perpendicular to the longitudinal direction of the fourth main member54. The another end41of the second reinforcement part40is connected to the fourth main member54at a position in a portion of the fourth main member54that is adjacent to the fourth connector82A.

In the first and second embodiments, the two reinforcement parts40are arranged only at the one end (left end inFIGS.3,7) of the lattice structure in the longitudinal direction thereof, but no reinforcement part40is provided at the another end (right end inFIGS.3,7) of the lattice structure in the longitudinal direction thereof. However, the present invention is not limited to the configuration. In the present invention, reinforcement parts40having the same configuration as those described above may be provided at the another end of the lattice structure in the longitudinal direction thereof.

The present invention should not be limited to the embodiments described above. The present invention covers, for example, aspects which will be described below.

First Modification

FIG.11is a schematic sideview of a lattice structure32(33) according to a first modification of the first and second embodiments. In the first modification, a nearest diagonal member601has one end which is not connected to a first connector71A, but is connected to a first main member51. The remaining configurations of the lattice structure32(33) according to the first modification are equivalent to those in the first embodiment or the second embodiment.

Second Modification

FIG.12is a schematic sideview of a lattice structure32(33) according to a second modification of the first and second embodiments. In the second modification, a reinforcement part40has another end41which is not connected to a second main member52, but is connected to a second connector72A. In the second modification, the reinforcement part40is arranged in a posture extending in a direction (perpendicular direction) perpendicular to a longitudinal direction of the lattice structure or inclined in a direction at an angle to the perpendicular direction. The remaining configurations of the lattice structure32(33) according to the second modification are equivalent to those in the first embodiment or the second embodiment.

Third Modification

FIG.13is a schematic sideview of a lattice structure according to a third modification of the first and second embodiments. In the third modification, a nearest diagonal member601has one end which is not connected to a first connector71A, but is connected to a first main member51. In the third modification, a reinforcement part40has another end41which is not connected to a second main member52, but is connected to a second connector72A. In this way, the reinforcement part40connects the nearest diagonal member601and the second connector72A with each other. In other words, the reinforcement part40connects the nearest diagonal member601and the second main member52with each other via the second connector72A. In the third modification, a first specific direction corresponding to a longitudinal direction of the reinforcement part40does not indicate a direction (perpendicular direction) perpendicular to a longitudinal direction of the lattice structure, but indicates a direction at an angle to the perpendicular direction. The remaining configurations of the lattice structure32(33) according to the third modification are equivalent to those in the first embodiment or the second embodiment.

Lattice Structure According to Third Embodiment

FIG.14is a perspective view of a lattice structure32according to a third embodiment, andFIG.15is a sideview thereof.FIG.16is an enlarged perspective view of a portion in a framed box XVI inFIG.14, andFIG.17is a sideview thereof. A basic configuration of the lattice structure32according to the third embodiment is similar to that of the lattice structure32according to the first embodiment.

The lattice structure32according to the third embodiment shown inFIG.14serves as, for example, the boom member32shown inFIG.1, and a lattice structure33(boom member33) is couplable to the lattice structure32. The lattice structure32and the lattice structure33have the same configuration in the third embodiment as well. As shown inFIG.14andFIG.15, each of the lattice structures32,33according to the third embodiment includes four main members50, a plurality of connectors75A,75B, a plurality of diagonal members60, a plurality of reinforcement parts40, and a plurality of sub-reinforcement parts45.

Main Member

Each of the four main members50is a linearly extending pipe (main pie) in the third embodiment as well. The four main members50include a first main member51, a second main member52, a third main member53, and a fourth main member54in the same manner as those in the first embodiment.

Connector

Each of the connectors is connected to a corresponding one of one end and another end of each of the four main members50. In the specific examples shown inFIGS.14and15, each of the first to fourth main members51to54has one end (left end inFIG.14andFIG.15) to which, for example, the female connector75A is connected and another end (right end inFIG.15) to which, for example, the male connector75B is connected. However, the female connector75A and the male connector75B shown inFIG.14andFIG.15may be interchanged.

As shown inFIG.14toFIG.17, central axes L of pin insertion holes (axial directions L of pins) of the four connectors75A each connected to the corresponding one end of each of the first to fourth main members51to54are parallel to one another. Although unillustrated, central axes of pin insertion holes (axial directions of pins) of the four connectors75B each connected to the corresponding another end of each of the first to fourth main members51to54are parallel to one another, and parallel to the central axes L of the insertion holes of the four connectors75A. The female connector75A and the male connector75B are rotatably connected to each other by the pin. These connectors75A,75B compose a coupling unit for the adjacent lattice structures32,33.

The connector75A has a main member joint for joining the main member50thereto while having no diagonal member joint like the diagonal member joint shown inFIG.4andFIG.5. Similarly, the connector75B has a main member joint for joining the main member50thereto while having no diagonal member joint. In other words, the main member50is connected to each of the connector75A and75B while no diagonal member60is connected thereto.

Diagonal Member

Each of the diagonal members60is a pipe (diagonal pipe) linearly extending so as to be inclined with respect to a longitudinal direction of the lattice structure in the third embodiment as well. Each of the diagonal member60has one end in a longitudinal direction (axial direction) thereof and another end opposite the one end in the longitudinal direction. Each diagonal member60connects two adjacent main members among the four main members with each other. The diagonal members60include a plurality of nearest diagonal members601to604in the same manner as those in the first embodiment.

Nearest Diagonal Member

As shown inFIG.14, the four nearest diagonal members601to604are located near one end (left end inFIG.14andFIG.15) of the lattice structure32in the longitudinal direction thereof and near another end (right end inFIG.15) of the lattice structure32in the longitudinal direction thereof.

In the third embodiment, each of the nearest diagonal members601to604is a member having a prism-shape as shown inFIG.14andFIG.16. However, each of the nearest diagonal members601to604may be a cylindrical member (cylindrical pipe) like that in the first embodiment, or may be a shaped steel member, such as an H-steel member and a channel steel member. Further, each of the nearest diagonal members may be a hollow member like a pipe, or a solid member.

The H-steel member has a pair of flanges extending parallel to each other and a web perpendicular to the flanges for connecting the flanges with each other. Each of the flanges and the web constitutes a portion of the nearest diagonal member that extends in a longitudinal direction of the nearest diagonal member. The web is located to connect a center section of one flange of the flanges in a width direction of the one flange and a center section of the other flange of the flanges in a width direction of the other flange. The web may be located to connect another section of the one flange deviating from the center section in the width direction thereof and another section of the other flange deviating from the center section in the width direction thereof with each other.

The channel steel member may be a lip channel steel member (C-steel member) or a light channel steel member. The channel steel member has a pair of flanges extending parallel to each other and a web being perpendicular to the flanges for connecting the flanges with each other. Each of the flanges and web constitutes a portion of the nearest diagonal member that extends in a longitudinal direction of the nearest diagonal member. The web is located to connect respective ends of the flanges in the width direction with each other.

Each of the H-steel member and the channel steel member has an unillustrated opening having a groove-shape and defined by the pair of flanges and the web. For instance, as shown inFIG.16, the nearest diagonal member601is preferably arranged in such a posture as to allow the opening to face a sub-reinforcement part451between the first main member51and a reinforcement part401. A narrow region between one end of the nearest diagonal member601to be welded to the first main member51and the sub-reinforcement part451may make it difficult to perform a welding operation of connecting a portion of the one end of the nearest diagonal member601that is nearer to the sub-reinforcement part451to the first main member51, the portion of the one end of the nearest diagonal member601being opposite to another portion thereof nearer to the connector75A. In this case, a shaped steel member having the aforementioned opening is adoptable as the nearest diagonal member601, and the shaped steel member is arranged in such a posture as to allow the opening to face the sub-reinforcement part451. This configuration can more effectively aim at a decrease in workloads required for the welding operation and at weight reduction than a configuration adopting, as the nearest diagonal member601, a member having a cylindrical shape with a closed section. In the nearest diagonal member601, the opening is continuous from the one end to another end of the nearest diagonal member601. However, the opening may be defined only in, for example, a portion of the nearest diagonal member601between the first main member51and the reinforcement part401.

The nearest diagonal member601is a diagonal member60located nearest to the connector75A connected to the one end of the first main member51among the diagonal members60connecting the first main member51and the second main member52with each other. As shown inFIG.16, the one end of the nearest diagonal member601is connected to a portion of the first main member51that is adjacent to the connector75A, and the another end of the nearest diagonal member601is connected to the second main member52. In this way, the nearest diagonal member601connects the first main member51and the second main member52with each other. The nearest diagonal member601is a continuous member linearly and continuously extending from the first main member51to the second main member52. Specifically, the nearest diagonal member601is made of a single member from the first main member51to the second main member52.

The nearest diagonal member602is a diagonal member60located nearest to the connector75A connected to one end of the second main member52among the diagonal members60connecting the second main member52and the third main member53with each other. The nearest diagonal member602has one end connected to a portion of the second main member52that is adjacent to the connector75A, and another end connected to the third main member53. In this way, the nearest diagonal member602connects the second main member52and the third main member53with each other. The nearest diagonal member602is a continuous member linearly and continuously extending from the second main member52to the third main member53. Specifically, the nearest diagonal member602is made of a single member from the second main member52to the third main member53.

The nearest diagonal member603is a diagonal member60located nearest to the connector75A connected to one end of the third main member53among the diagonal members60connecting the third main member53and the fourth main member54with each other. The nearest diagonal member603has one end connected to a portion of the third main member53that is adjacent to the connector75A, and another end connected to the fourth main member54. In this way, the nearest diagonal member603connects the third main member53and the fourth main member54with each other. The nearest diagonal member603is a continuous member linearly and continuously extending from the third main member53to the fourth main member54. Specifically, the nearest diagonal member603is made of a single member from the third main member53to the fourth main member54.

The nearest diagonal member604is a diagonal member60located nearest to the connector75A connected to one end of the fourth main member54among the diagonal members60connecting the fourth main member54and the first main member51with each other. The nearest diagonal member604has one end connected to a portion of the fourth main member54that is adjacent to the connector75A, and another end connected to the first main member51. In this way, the nearest diagonal member604connects the fourth main member54and the first main member51with each other. The nearest diagonal member604is a continuous member linearly and continuously extending from the fourth main member54to the first main member51. Specifically, the nearest diagonal member604is made of a single member from the fourth main member54to the first main member51.

Reinforcement Part

Each of the reinforcement parts40is a linearly extending pipe (reinforcement pipe) in the third embodiment as well. However, each of the reinforcement parts40may be, for example, a member having a prism-shape, or a shaped steel member, such as an H-steel member and a channel steel member. Moreover, each of the reinforcement parts40may be a solid member.

In the third embodiment, the reinforcement parts40include a reinforcement part401, a reinforcement part402, a reinforcement part403, and a reinforcement part404. The four reinforcement parts401to404are respectively arranged at the one end (left end inFIG.14andFIG.15) of the lattice structure32in the longitudinal direction thereof and another end (right end inFIG.15) of the lattice structure32in the longitudinal direction thereof.

Specifically, as shown inFIG.14toFIG.17, the reinforcement part401has one end42and another end41in a longitudinal direction thereof, the one end42being connected to the nearest diagonal member601and the another end41being connected to the second main member52. The reinforcement part401extends from the nearest diagonal member601to the second main member52in the longitudinal direction for connecting the nearest diagonal member601and the second main member52with each other. The longitudinal direction of the reinforcement part401is perpendicular to the longitudinal direction of the lattice structure. Specifically, the longitudinal direction of the reinforcement part401indicates a direction (exemplary first specific direction) perpendicular to the longitudinal direction of the lattice structure and perpendicular to the central axis L of the pin insertion hole (axial direction L of the pin) of the connector75A.

As shown inFIG.14, the reinforcement part402has one end and another end in a longitudinal direction thereof, the one end being connected to the nearest diagonal member602and the another end being connected to the third main member53. The reinforcement part402extends from the nearest diagonal member602to the third main member53in the longitudinal direction thereof for connecting the nearest diagonal member602and the third main member53with each other. The longitudinal direction of the reinforcement part402is perpendicular to the longitudinal direction of the lattice structure. Specifically, the longitudinal direction of the reinforcement part402is perpendicular to the longitudinal direction of the lattice structure and parallel to the central axis L of the pin insertion hole (axial direction L of the pin) of the connector75A.

The reinforcement part403has one end and another end in a longitudinal direction thereof, the one end being connected to the nearest diagonal member603and the another end being connected to the fourth main member54. The reinforcement part403extends from the nearest diagonal member603to the fourth main member54in the longitudinal direction thereof for connecting the nearest diagonal member603and the fourth main member54with each other. The longitudinal direction of the reinforcement part403is perpendicular to the longitudinal direction of the lattice structure. Specifically, the longitudinal direction of the reinforcement part403indicates a direction (exemplary second specific direction) perpendicular to the longitudinal direction of the lattice structure and perpendicular to the central axis L of the pin insertion hole (axial direction L of the pin) of the connector75A.

The reinforcement part404has one end and another end in a longitudinal direction thereof, the one end being connected to the nearest diagonal member604and the another end being connected to the first main member51. The reinforcement part404extends from the nearest diagonal member604to the first main member51in the longitudinal direction thereof for connecting the nearest diagonal member604and the first main member51with each other. The longitudinal direction of the reinforcement part404is perpendicular to the longitudinal direction of the lattice structure. Specifically, the longitudinal direction of the reinforcement part404is perpendicular to the longitudinal direction of the lattice structure and parallel to the central axis L of the pin insertion hole (axial direction L of the pin) of the connector75A.

Sub-Reinforcement Part

Each of the sub-reinforcement parts45is a linearly extending pipe (sub-reinforcement pipe). However, each of the sub-reinforcement parts45may be, for example, a member having a prism-shape. Each of the sub-reinforcement parts45may be made of at least a plate-like member, a shaped steel member, such as a H-steel member and a channel steel member, or a member having a box shape.

The sub-reinforcement parts45include a sub-reinforcement part451, a sub-reinforcement part452, a sub-reinforcement part453, and a sub-reinforcement part454. The four sub-reinforcement parts451to454are respectively arranged at the one end (left end inFIG.14andFIG.15) of the lattice structure32in the longitudinal direction thereof and another end (right end inFIG.15) of the lattice structure32in the longitudinal direction thereof. More details will be described below.

As shown inFIG.14toFIG.17, the sub-reinforcement part451has one end44connected to the first main member51and another end43connected to the nearest diagonal member601. The sub-reinforcement part451extends from the first main member51to the nearest diagonal member601in a longitudinal direction thereof for connecting the first main member51and the nearest diagonal member601with each other. The sub-reinforcement part451is arranged at such a position as to overlap the reinforcement part401when the sub-reinforcement part451is viewed in the longitudinal direction (first specific direction) of the reinforcement part401. Specifically, the sub-reinforcement part451extends from the first main member51to the nearest diagonal member601in a direction parallel to the longitudinal direction (first specific direction) of the reinforcement part401. More specifically, in the third embodiment, a central axis of the reinforcement part401and a central axis of the sub-reinforcement part451are substantially on the same straight line L1, as shown inFIG.17.

As shown inFIG.14, the sub-reinforcement part452has one end connected to the second main member52and another end connected to the nearest diagonal member602. The sub-reinforcement part452extends from the second main member52to the nearest diagonal member602in a longitudinal direction thereof for connecting the second main member52and the nearest diagonal member602with each other. The sub-reinforcement part452is arranged at such a position as to overlap the reinforcement part402when the sub-reinforcement part452is viewed in the longitudinal direction of the reinforcement part402. Specifically, the sub-reinforcement part452extends from the second main member52to the nearest diagonal member602in a direction parallel to the longitudinal direction of the reinforcement part402. More specifically, in the third embodiment, a central axis of the reinforcement part402and a central axis of the sub-reinforcement part452are substantially on the same straight line.

The sub-reinforcement part453has one end connected to the third member53and another end connected to the nearest diagonal member603. The sub-reinforcement part453extends from the third member53to the nearest diagonal member603in a longitudinal direction thereof for connecting the third main member53and the nearest diagonal member603with each other. The sub-reinforcement part453is arranged at such a position as to overlap the reinforcement part403when the sub-reinforcement part453is viewed in the longitudinal direction (second specific direction) of the reinforcement part403. Specifically, the sub-reinforcement part453extends from the third main member53to the nearest diagonal member603in a direction parallel to the longitudinal direction (second specific direction) of the reinforcement part403. More specifically, in the third embodiment, a central axis of the reinforcement part403and a central axis of the sub-reinforcement part453are substantially on the same straight line.

The sub-reinforcement part454has one end connected to the fourth main member54and another end connected to the nearest diagonal member604. The sub-reinforcement part454extends from the fourth main member54to the nearest diagonal member604in a longitudinal direction thereof for connecting the fourth main member54and the nearest diagonal member604with each other. The sub-reinforcement part454is arranged at such a position as to overlap the reinforcement part404when the sub-reinforcement part454is viewed in the longitudinal direction of the reinforcement part404. Specifically, the sub-reinforcement part454extends from the fourth main member54to the nearest diagonal member604in a direction parallel to the longitudinal direction of the reinforcement part404. More specifically, in the third embodiment, a central axis of the reinforcement part404and a central axis of the sub-reinforcement part454are substantially on the same straight line.

A way of connecting or joining the one end and the another end of each of the reinforcement parts40to the corresponding nearest diagonal member and main member, and a way of connecting or joining the one end and the another end of each of the sub-reinforcement parts45to the corresponding main member and nearest diagonal member are not particularly limited. For example, a joining way, such as welding, may be adoptable.

The lattice structure according to the third embodiment includes the plurality of sub-reinforcement parts45in addition to the plurality of reinforcement parts40. Specifically, each of the reinforcement parts40and each of the sub-reinforcement parts45support the corresponding one of the nearest diagonal members601to604at the opposite positions thereacross. Therefore, the lattice structure according to the third embodiment more effectively suppresses deformation of each of the nearest diagonal members601to604than the lattice structure according to the first and second embodiments including no sub-reinforcement part45, and thus has further improved stiffness.

In the third embodiment, the sub-reinforcement part45is arranged at such a position as to overlap the reinforcement part40when the sub-reinforcement part45is viewed in the longitudinal direction of the reinforcement part40. In this configuration, a load is effectively transmitted from the reinforcement part40to the sub-reinforcement part45, and a load is effectively transmitted from the sub-reinforcement part45to the reinforcement part40in a work performed by the working machine.

In the third embodiment, the sub-reinforcement part451extends from the first main member51to the nearest diagonal member601in a direction parallel to the longitudinal direction of the reinforcement part401, and the sub-reinforcement part453extends from the third main member53to the nearest diagonal member603in a direction parallel to the longitudinal direction of the reinforcement part403. In this configuration, the longitudinal direction of each of the sub-reinforcement parts451,453approximates to a direction in which buckling deformation of the lattice structure may occur. Accordingly, the buckling strength is further effectively improved.

In the third embodiment, connecting the reinforcement part40and the sub-reinforcement part45to the corresponding one of the nearest diagonal members601to604that is the continuous member attains arrangement of the end of the nearest diagonal member nearer to the connector75A than the sub-reinforcement part45. This arrangement achieves a smaller gap between the end of the nearest diagonal member and the connector75A (specifically, the pin insertion hole of the connector75A). More specifically, in the sideview shown inFIG.17, this arrangement can achieve, for example, a shorter distance G between an intersection of a central axis of the first main member51and a central axis of the first nearest diagonal member601, and a center of the pin insertion hole of the connector75A. Accordingly, in the third embodiment, an effect of the improved buckling strength is obtainable by the first reinforcement part401and the sub-reinforcement part451in the coupling unit composed of the pair of connectors75A,75B and therearound. Additionally, the aforementioned triangular configuration (lattice configuration) or a configuration similar to the lattice configuration in the coupling unit and therearound can exert an effect of suppressing lowering in the buckling strength.

In the third embodiment, each of the nearest diagonal members601to604that is the continuous member as described above can be made of a single member. A nearest diagonal member made of a single member can more smoothly transmit a load at the nearest diagonal member than a nearest diagonal member composed of a plurality of members connected to each other. This can further effectively improve the stiffness of the lattice structure.

A load acting on each of the reinforcement part40and the sub-reinforcement part45is highly likely to be smaller than a load acting on the nearest diagonal member to which these parts are connected in a work performed by the working machine. Hence, an outer diameter of each of the reinforcement part40and the sub-reinforcement part45can be made smaller than an outer diameter of the nearest diagonal member. In this case, weight reduction in the lattice structure is achievable. Furthermore, in this case, each of the reinforcement part40and the sub-reinforcement part45having the relatively small diameter is easily connectable to the nearest diagonal member having the relatively large diameter by using a connection or joining way, e.g., welding.

Modification

FIG.18is a perspective view of a portion of each of lattice structures32,33according to a modification of the third embodiment. In the modification of the third embodiment shown inFIG.18, the lattice structure32includes a nearest diagonal member601having one end which is not connected to a first main member51, but is connected to a diagonal member joint74of a connector76B joined to an end of a first main member51. Similarly, a lattice structure33includes a nearest diagonal member601having one end which is not connected to a first main member51, but is connected to a diagonal member joint74of a connector76A joined to an end of the first main member51. The modification shown inFIG.18differs from the lattice structure32(33) shown inFIG.14toFIG.17in this respect, but the remaining configurations of the modification are equivalent to those of the lattice structure32(33) shown inFIGS.14to17.

In this modification, the one end of each of the two nearest diagonal members601,601is connected to corresponding one of the connector76A and the connector76B. Accordingly, each of the nearest diagonal members601,601can contribute to an ideal lattice configuration in a coupling unit for coupling the lattice structures32,33to each other. This configuration can further effectively suppress lowering in the stiffness of each of the lattice structures32,33in the coupling unit and therearound.

Lattice Structure According to Fourth Embodiment

FIG.19is a perspective view of a main portion of a lattice structure according to a fourth embodiment.FIG.20is a perspective view showing components for use in manufacturing the lattice structure according to the fourth embodiment. A region occupied by the main portion shown inFIG.19in the lattice structure according to the fourth embodiment corresponds to the portion in the framed box XVI inFIG.14.

The lattice structure according to the fourth embodiment includes four main members51to54, a plurality of connectors75A,75B, a plurality of diagonal members60, a plurality of reinforcement parts40, and a plurality of sub-reinforcement parts45. As shown inFIG.19, the first main member51has one end to which the male connector75B is connected and another end to which the female connector75A (not shown) is connected.

A basic configuration of the lattice structure according to the fourth embodiment shown inFIG.19is similar to that of the lattice structure32(33) according to the third embodiment shown inFIG.14toFIG.17. Hereinafter, the differences between the fourth embodiment and the third embodiment will be mainly described.

Reinforcement Part and Sub-Reinforcement Part

In the fourth embodiment, the reinforcement parts40include a reinforcement part401, a reinforcement part402, a reinforcement part403, and a reinforcement part404. Further, the sub-reinforcement parts45include a sub-reinforcement part451, a sub-reinforcement part452, a sub-reinforcement part453, and a sub-reinforcement part454. The reinforcement parts401to404and the sub-reinforcement parts451to454in the lattice structure according to the fourth embodiment are provided in substantially the same portions as the portions where the reinforcement parts401to404and the sub-reinforcement parts451to454in the lattice structure according to the third embodiment shown inFIG.14are provided.

In the fourth embodiment, each of the reinforcement parts40constitutes a portion of a corresponding continuous member46to be described below, and each of the sub-reinforcement parts45constitutes another portion of the continuous member46. More details will be described below.

The lattice structure32(33) according to the fourth embodiment shown inFIG.19includes a plurality of continuous members46. The continuous members46include a first continuous member461, a second continuous member462, a third continuous member463, and a fourth continuous member464. The continuous members461to464are respectively provided near one end of the lattice structure in a longitudinal direction thereof and near another end of the lattice structure in the longitudinal direction thereof.

In the fourth embodiment, each of the continuous members46is a linearly extending single pipe as shown inFIG.20, but may be a linearly extending solid member. The continuous member46may be a linearly extending plate-like member, or a linearly extending shaped steel member, such as an H-steel member and a channel steel member.

The first continuous member461is located in a portion corresponding to the portion where the reinforcement part401and the sub-reinforcement part451in the third embodiment shown inFIG.14toFIG.17are located. The second continuous member462(not shown) is located in a portion corresponding to the portion where the reinforcement part402and the sub-reinforcement part452in the third embodiment are located. The third continuous member463(not shown) is located in a portion corresponding to the portion where the reinforcement part403and the sub-reinforcement part453in the third embodiment are located. The fourth continuous member464(not shown) is located in a portion corresponding to the portion where the reinforcement part404and the sub-reinforcement part454in the third embodiment are located. More details will be described below.

As shown inFIG.19andFIG.20, the first continuous member461linearly and continuously extends from the first main member51to the second main member52in a longitudinal direction (first specific direction) of the first continuous member, and is made of a single member. The second continuous member462linearly and continuously extends from the second main member52to the third main member53in a longitudinal direction of the second continuous member, and is made of a single member. The third continuous member463linearly and continuously extends from the third main member53to the fourth main member54in a longitudinal direction (second specific direction) of the third continuous member, and is made of a single member. The fourth continuous member464linearly and continuously extends from the fourth main member54to the first main member51in a longitudinal direction of the fourth continuous member, and is made of a single member.

As shown inFIG.19, the continuous member461includes the reinforcement part401, the sub-reinforcement part451, and an intermediate section60C located therebetween. In the continuous member461, the reinforcement part401, the intermediate section60C, and the sub-reinforcement part451are arranged in this order in the longitudinal direction of the continuous member461.

The reinforcement part401constitutes a portion of the continuous member461, the portion including an end of the continuous member461that is connected to the second main member52. Specifically, the reinforcement part401extends, in the continuous member461, from the intermediate section60C to the second main member52.

The sub-reinforcement part451constitutes another portion of the continuous member461, the another portion including another end of the continuous member461that is connected to the first main member51. Specifically, the sub-reinforcement part451extends, in the continuous member461, from the first main member51to the intermediate section60C.

Although unillustrated, each of the continuous members462to464has the same configuration as the continuous member461. Specifically, the reinforcement part402constitutes a portion of the continuous member462, the portion including an end of the continuous member462that is connected to the third main member53. More specifically, the reinforcement part402extends, in the continuous member462, from an intermediate section60C to the third main member53. The sub-reinforcement part452constitutes another portion of the continuous member462, the another portion including another end of the continuous member462that is connected to the second main member52. Specifically, the sub-reinforcement part452extends, in the continuous member462, from the second main member52to the intermediate section60C.

The reinforcement part403constitutes a portion of the continuous member463, the portion including an end of the continuous member463that is connected to the fourth main member54. Specifically, the reinforcement part403extends, in the continuous member463, from an intermediate section60C to the fourth main member54. The sub-reinforcement part453constitutes another portion of the continuous member463, the another portion including another end of the continuous member463that is connected to the third main member53. Specifically, the sub-reinforcement part453extends, in the continuous member463, from the third main member53to the intermediate section60C.

The reinforcement part404constitutes a portion of the continuous member464, the portion including an end of the continuous member464that is connected to the first main member51. Specifically, the reinforcement part404extends, in the continuous member464, from an intermediate section60C to the first main member51. The sub-reinforcement part454constitutes another portion of the continuous member464, the another portion including another end of the continuous member464that is connected to the fourth main member54. Specifically, the sub-reinforcement part454extends, in the continuous member464, from the fourth main member54to the intermediate section60C.

Nearest Diagonal Member

The diagonal members60in the lattice structure according to the fourth embodiment include a plurality of nearest diagonal members601to604respectively located in portions similar to those in the third embodiment.

In the fourth embodiment, each of the nearest diagonal members601to604includes: the intermediate section60C included in the continuous member46; a first member60A connected to the intermediate section60C and extending from the intermediate section60C to a certain main member50; and a second member603connected to the intermediate section60C and extending from the intermediate section GOC to another main member50adjacent to the certain main member50. Hereinafter, more details will be described.

The nearest diagonal member601is arranged so that one end of the nearest diagonal member601is connected to the first main member51and another end of the nearest diagonal member601is connected to the second main member52. In this way, the nearest diagonal member601connects the first main member51and the second main member52with each other. As shown inFIG.19, the nearest diagonal member601includes: an intermediate section60C (located between the reinforcement part401and the sub-reinforcement part451) included in the continuous member461; a first member60A connected to the intermediate section60C and extending from the intermediate section60C to the first main member51; and a second member60B connected to the intermediate section60C and extending from the intermediate section60C to the second main member52.

Although unillustrated, each of the nearest diagonal member602to604has the same configuration as the nearest diagonal member601.

Specifically, the nearest diagonal member602is arranged so that one end of the nearest diagonal member602is connected to the second main member52and another end of the nearest diagonal member602is connected to the third main member53. In this way, the nearest diagonal member602connects the second main member52and the third main member53with each other. The nearest diagonal member602includes: an intermediate section60C (located between the reinforcement part402and the sub-reinforcement part452) included in the continuous member462; a first member60A connected to the intermediate section60C and extending from the intermediate section60C to the second main member52; and a second member60B connected to the intermediate section60C and extending from the intermediate section60C to the third main member53.

The nearest diagonal member603is arranged so that one end of the nearest diagonal member603is connected to the third main member53and another end of the nearest diagonal member603is connected to the fourth main member54. In this way, the nearest diagonal member603connects the third main member53and the fourth main member54with each other. The nearest diagonal member603includes: an intermediate section60C (located between the reinforcement part403and the sub-reinforcement part453) included in the continuous member463; a first member60A connected to the intermediate section60C and extending from the intermediate section60C to the third main member53; and a second member60B connected to the intermediate section60C and extending from the intermediate section60C to the fourth main member54.

The nearest diagonal member604is arranged so that one end of the nearest diagonal member604is connected to the fourth main member54and another end of the nearest diagonal member604is connected to the first main member51. In this way, the nearest diagonal member604connects the fourth main member54and the first main member51with each other. The nearest diagonal member604includes: an intermediate section60C (located between the reinforcement part404and the sub-reinforcement part454) included in the continuous member464; a first member60A connected to the intermediate section60C and extending from the intermediate section60C to the fourth main member54; and a second member60B connected to the intermediate section60C and extending from the intermediate section60C to the first main member51.

The one end of each of the nearest diagonal members601to604(one end of the first member60A) is connected to the corresponding main member50at a position in a portion of the main member50that is adjacent to the connector75B, for example as shown inFIG.19. However, the one end of each of the nearest diagonal members601to604(one end of the first member60A) may be connected to the connector75B in place of the main member50.

In the fourth embodiment shown inFIGS.19and20, each of the first member60A and the second member60B is a cylindrical member (cylindrical pipe). At least one of the first member60A and the second member60B may be, for example, a plate-like member, a member having a prism-shape, or a shaped steel member, such as an H-steel member and a channel steel member. Alternatively, at least one of the first member60A and the second member60B may be a solid member instead of a pipe.

For instance, in a case where the first member60A is a H-steel member or a channel steel member, the first member60A is preferably arranged in such a posture as to allow an unillustrated opening formed in the H-steel member or the channel steel member to face the sub-reinforcement part451inFIG.19. A narrow region between the one end of the first member60A to be welded to the first main member51and the sub-reinforcement part451may make it difficult to perform a welding operation of connecting a portion of the one end of the first member60A that is closer to the sub-reinforcement part451to the first main member51, the portion of the one end of the first member60A being opposite to another portion thereof that is closer to the connector75B. In this case, a shaped steel member having the aforementioned opening is adoptable as the first member60A, and the shaped steel member is arranged in such a posture as to allow the opening to face the sub-reinforcement part451. This configuration can more effectively aim at a decrease in workloads required for the welding operation and at weight reduction than a configuration adopting, as the first member60A, a member having a cylindrical shape with a closed section.

As described above, in the fourth embodiment, the reinforcement part40constitutes a portion of the continuous member46, and the sub-reinforcement part45constitutes another portion of the continuous member46. Further, each of the nearest diagonal members601to604includes the inter mediate section60C included in the continuous member46, and the first member60A and the second member60B each connected to the intermediate section. Therefore, for instance, as shown inFIG.19, the end of the first nearest diagonal member601is arrangeable to be nearer to the connector75B than the sub-reinforcement part451. This arrangement achieves a smaller gap between the end of the nearest diagonal member601and the connector75B (specifically, a pin insertion hole of the connector75B). Accordingly, in the fourth embodiment, an effect of the improved buckling strength is obtainable by the reinforcement part40and the sub-reinforcement part45in the coupling unit and therearound. Additionally, the aforementioned triangular configuration (lattice configuration) or a configuration similar to the lattice configuration in the coupling unit and therearound can exert an effect of suppressing lowering in the buckling strength.

Moreover, in the fourth embodiment, adoption of the configuration including the first member60A and the second member60B each connected to the intermediate section60C of the continuous member46succeeds in forming the continuous member46including the reinforcement part40and the sub-reinforcement part45by a single member. A continuous member46made of a single member can more effectively suppress a decrease in a dimensional accuracy of the continuous member46in the longitudinal direction thereof than a continuous member46composed of a plurality of members connected to each other. For instance, this configuration can easily ensure accuracy of a distance between the connector75B connected to the first main member51and the connector75B connected to the second main member52, specifically, accuracy of a distance between pin insertion holes of the connectors75B,75B.

In the fourth embodiment, the first member60A is arranged at such a position as to overlap the second member60B when the first member60A is viewed in a longitudinal direction of the second member60B. In this configuration, a load is effectively transmitted from the first member60A to the second member60B, and a load is effectively transmitted from the second member60B to the first member60A in a work performed by the working machine.

Specifically, a longitudinal direction of the first member60A is parallel to the longitudinal direction of the second member60B. In this configuration, a load is further effectively transmitted from the first member60A to the second member60B, and a load is further effectively transmitted from the second member60B to the first member60A in a work performed by the working machine. More specifically, in the fourth embodiment, a central axis of the first member60A and a central axis of the second member60B are substantially on the same straight line L2, as shown inFIG.19.

First Modification

FIG.21is a perspective view of a portion of a lattice structure according to a first modification of the fourth embodiment. In the first modification, as shown inFIG.21, a nearest diagonal member601includes a first member60A which is a member having a prism-shape and a second member60B which is a cylindrical pipe. The remaining configurations in the first modification are equivalent to those in the fourth embodiment shown inFIG.19andFIG.20.

Second Modification

FIG.22is a perspective view of a portion of a lattice structure according to a second modification of the fourth embodiment. In the second modification shown inFIG.22, a lattice structure32includes a nearest diagonal member601having one end which is not connected to a first main member51, but is connected to a diagonal member joint74of a connector76B joined to an end of the first main member51. Similarly, a lattice structure33includes a nearest diagonal member601having one end which is not connected to a first main member51, but is connected to a diagonal member joint74of a connector76A joined to an end of the first main member51. The one end of each of the two nearest diagonal members601,601is connected to corresponding one of the connector76A and the connector76B. Accordingly, each of the nearest diagonal members601,601can contribute to an ideal lattice configuration in a coupling unit for coupling the lattice structures32,33to each other. This configuration can effectively suppress lowering in the stiffness of each of the lattice structures32,33in the coupling unit and therearound.

In the second modification, the nearest diagonal member601includes a first member60A which is a plate-like member and a second member60B which is a cylindrical pipe. The remaining configurations in the second modification are equivalent to those in the fourth embodiment shown inFIG.19andFIG.20.

Lattice Structure According to Fifth Embodiment

FIG.23is a sideview of a main portion of a lattice structure according to a fifth embodiment.FIG.24is a sideview showing components for use in manufacturing the lattice structure according to the fifth embodiment. A region occupied by the main portion shown inFIG.23in the lattice structure according to the fifth embodiment corresponds to the portion in the framed box XVI inFIG.14.

The lattice structure according to the fifth embodiment includes four main members51to54, a plurality of connectors75A,75B, a plurality of diagonal members60, a plurality of reinforcement parts40, and a plurality of sub-reinforcement parts45. As shown inFIG.23, the first main member51has one end to which the female connector75A is connected and another end to which the male connector75B (not shown) is connected.

A basic configuration of the lattice structure according to the fifth embodiment shown inFIG.23is similar to that of the lattice structure32(33) according to the third embodiment shown inFIG.14toFIG.17. Hereinafter, the differences between the fifth embodiment and the third embodiment will be mainly described.

Nearest Diagonal Member

The diagonal members60in the lattice structure according to the fifth embodiment include a plurality of nearest diagonal members601to604respectively located in portions similar to those in the third embodiment.

In the fifth embodiment, each of the nearest diagonal members601to604is a continuous member linearly and continuously extending from one of two adjacent main members to the other of the main members. Specifically, each of the nearest diagonal members601to604is made of a single member from one of two adjacent main members to the other of the main members. Each of the nearest diagonal members601to604is a linearly extending single pipe, but may be a linearly extending solid member. The continuous member46may be a linearly extending plate-like member, or a linearly extending shaped steel member, such as an H-steel member and a channel steel member. Hereinafter, more details will be described.

The nearest diagonal member601is arranged so that one end of the nearest diagonal member601is connected to the first main member51and another end of the nearest diagonal member601is connected to the second main member52. In this way, the nearest diagonal member601connects the first main member51and the second main member52with each other. The nearest diagonal member601is a continuous member made of a single member linearly and continuously extending from the first main member51to the second main member52.

Although unillustrated, each of the nearest diagonal member602to604has the same configuration as the nearest diagonal member601.

Specifically, the nearest diagonal member602is arranged so that one end of the nearest diagonal member602is connected to the second main member52and another end of the nearest diagonal member602is connected to the third main member53. In this way, the nearest diagonal member602connects the second main member52and the third main member53with each other. The nearest diagonal member602is a continuous member made of a single member linearly and continuously extending from the second main member52to the third main member53.

The nearest diagonal member603is arranged so that one end of the nearest diagonal member603is connected to the third main member53and another end of the nearest diagonal member603is connected to the fourth main member54. In this way, the nearest diagonal member603connects the third main member53and the fourth main member54with each other. The nearest diagonal member603is a continuous member made of a single member linearly and continuously extending from the third main member53to the fourth main member54.

The nearest diagonal member604is arranged so that one end of the nearest diagonal member604is connected to the fourth main member54and another end of the nearest diagonal member604is connected to the first main member51. In this way, the nearest diagonal member604connects the fourth main member54and the first main member51with each other. The nearest diagonal member604is a continuous member made of a single member linearly and continuously extending from the fourth main member54to the first main member51.

Reinforcement Part and Sub-Reinforcement Part

In the fifth embodiment, the reinforcement parts40include a reinforcement part401, a reinforcement part402, a reinforcement part403, and a reinforcement part404. Further, the sub-reinforcement parts45include a sub-reinforcement part451, a sub-reinforcement part452, a sub-reinforcement part453, and a sub-reinforcement part454. The reinforcement parts401to404and the sub-reinforcement parts451to454in the lattice structure according to the fifth embodiment are provided in substantially the same portions as the portions where the reinforcement parts401to404and the sub-reinforcement parts451to454in the lattice structure according to the third embodiment shown inFIG.14are provided.

In the fifth embodiment, each of the reinforcement parts40constitutes a portion of a corresponding reinforcement continuous member47to be described below, and each of the sub-reinforcement parts45constitutes another portion of the reinforcement continuous member47. More details will be described below.

A lattice structure32(33) according to the fifth embodiment shown inFIG.23includes a plurality of reinforcement continuous members47. The reinforcement continuous members47include a reinforcement continuous member471, a reinforcement continuous member472, a reinforcement continuous member473, and a reinforcement continuous member474. The reinforcement continuous members471to474are respectively provided near one end of the lattice structure in a longitudinal direction thereof and near another end of the lattice structure in the longitudinal direction thereof.

In the fifth embodiment, each of the reinforcement continuous members47is a linearly extending single pipe as shown inFIG.24, but may be a linearly extending solid member. The reinforcement continuous member47may be a linearly extending plate-like member, or a linearly extending shaped steel member, such as an H-steel member and a channel steel member.

As shown inFIG.23andFIG.24, the reinforcement continuous member471linearly and continuously extends from the first main member51to the second main member52in a longitudinal direction (first specific direction) of the reinforcement continuous member, and is made of a single member. The reinforcement continuous member472linearly and continuously extends from the second main member52to the third main member53in a longitudinal direction of the reinforcement continuous member, and is made of a single member. The reinforcement continuous member473linearly and continuously extends from the third main member53to the fourth main member54in a longitudinal direction (second specific direction) of the reinforcement continuous member, and is made of a single member. The reinforcement continuous member474linearly and continuously extends from the fourth main member54to the first main member51in a longitudinal direction of the reinforcement continuous member, and is made of a single member. The longitudinal direction of the reinforcement continuous member47is perpendicular to the longitudinal direction of the lattice structure.

As shown inFIG.23, the reinforcement continuous member471includes the reinforcement part401, the sub-reinforcement part451, and an intermediate section48located therebetween. In the reinforcement continuous member471, the reinforcement part401, the intermediate section48, and the sub-reinforcement part451are located in this order in the longitudinal direction of the reinforcement continuous member471. The reinforcement continuous member471has a through hole91penetrating the reinforcement continuous member471in a direction intersecting the longitudinal direction of the reinforcement continuous member471. The direction intersecting in the aforementioned manner corresponds to the longitudinal direction of the nearest diagonal member601. The through hole91is formed in the intermediate section48. The reinforcement part401constitutes a portion of the reinforcement continuous member471, the portion of the reinforcement continuous member471extending from the nearest diagonal member601to the second main member52. The sub-reinforcement part451constitutes another portion of the reinforcement continuous member471, the another portion of the reinforcement continuous member471extending from the first main member51to the nearest diagonal member601. Each of the reinforcement continuous members472to474has the same configuration as the reinforcement continuous member471.

The reinforcement continuous member472includes the reinforcement part402, the sub-reinforcement part452, and an intermediate section48located therebetween. In the reinforcement continuous member472, the reinforcement part402, the intermediate section48, and the sub-reinforcement part452are located in this order in the longitudinal direction of the reinforcement continuous member472. The reinforcement continuous member472has a through hole91penetrating the reinforcement continuous member472in a direction intersecting the longitudinal direction of the reinforcement continuous member472. The direction intersecting in the aforementioned manner corresponds to the longitudinal direction of the nearest diagonal member602. The through hole91is formed in the inteiinediate section48. The reinforcement part402constitutes a portion of the reinforcement continuous member472, the portion of the reinforcement continuous member472extending from the nearest diagonal member602to the third main member53. The sub-reinforcement part452constitutes another portion of the reinforcement continuous member472, the another portion of the reinforcement continuous member472extending from the second main member52to the nearest diagonal member602.

The reinforcement continuous member473includes the reinforcement part403, the sub-reinforcement part453, and an intermediate section48located therebetween. In the reinforcement continuous member473, the reinforcement part403, the intermediate section48, and the sub-reinforcement part453are located in this order in the longitudinal direction of the reinforcement continuous member473. The reinforcement continuous member473has a through hole91penetrating the reinforcement continuous member473in a direction intersecting the longitudinal direction of the reinforcement continuous member473. The direction intersecting in the aforementioned manner corresponds to the longitudinal direction of the nearest diagonal member603. The through hole91is formed in the intermediate section48. The reinforcement part403constitutes a portion of the reinforcement continuous member473, the portion of the reinforcement continuous member473extending from the nearest diagonal member603to the fourth main member54. The sub-reinforcement part453constitutes another portion of the reinforcement continuous member473, the another portion of the reinforcement continuous member473extending from the third main member53to the nearest diagonal member603.

The reinforcement continuous member474includes the reinforcement part404, the sub-reinforcement part454, and an intermediate section48located therebetween. In the reinforcement continuous member474, the reinforcement part404, the intermediate section48, and the sub-reinforcement part454are located in this order in the longitudinal direction of the reinforcement continuous member474. The reinforcement continuous member474has a through hole91penetrating the reinforcement continuous member474in a direction intersecting the longitudinal direction of the reinforcement continuous member474. The direction intersecting in the aforementioned manner corresponds to the longitudinal direction of the nearest diagonal member604. The through hole91is formed in the intermediate section48. The reinforcement part404constitutes a portion of the reinforcement continuous member474, the portion of the reinforcement continuous member474extending from the nearest diagonal member604to the first main member51. The sub-reinforcement part454constitutes another portion of the reinforcement continuous member474, the another portion of the reinforcement continuous member474extending from the fourth main member54to the nearest diagonal member604.

As shown inFIG.23andFIG.24, the nearest diagonal member601is inserted in the through hole91of the reinforcement continuous member471and arranged in such a manner as to intersect the reinforcement continuous member471. Although unillustrated, the nearest diagonal member602is inserted in the through hole91of the reinforcement continuous member472and arranged in such a manner as to intersect the reinforcement continuous member472. The nearest diagonal member603is inserted in the through hole91of the reinforcement continuous member473and arranged in such a manner as to intersect the reinforcement continuous member473. The nearest diagonal member604is inserted in the through hole91of the reinforcement continuous member474and arranged in such a manner as to intersect the reinforcement continuous member474.

Modification

FIG.25is a sideview of a portion of a lattice structure according to a modification of the fifth embodiment.FIG.26is a sideview showing components for use in manufacturing the lattice structure according to the modification of the fifth embodiment.

The lattice structure according to the modification of the fifth embodiment shown inFIG.25differs from the lattice structure shown inFIG.23in that each of nearest diagonal members601to604is formed with a through hole92in which a corresponding reinforcement continuous member47is inserted. The remaining configurations of the lattice structure according to the modification shown inFIG.25are equivalent to those of the lattice structure shown inFIG.23except the aforementioned difference.

In the modification, each of the nearest diagonal members601to604has the through hole92in an intermediate section610of the nearest diagonal member in a longitudinal direction thereof. The through hole92penetrates each of the nearest diagonal members601to604in a direction intersecting the longitudinal direction of the nearest diagonal member. The direction intersecting in the aforementioned manner corresponds to a longitudinal direction of the reinforcement continuous member47. In contrast, the reinforcement continuous member47in the modification excludes the through hole91shown inFIG.23.

As shown inFIG.25andFIG.26, the reinforcement continuous member47includes a reinforcement part40, a sub-reinforcement part45, and an intermediate section48located therebetween. In the reinforcement continuous member47, the reinforcement part40, the intermediate section48, and the sub-reinforcement part45are located in this order in the longitudinal direction of the reinforcement continuous member47. The intermediate section48of the reinforcement continuous member47is to fit in the through hole92of the corresponding nearest diagonal member.

As shown inFIG.25andFIG.26, a reinforcement continuous member471is inserted in the through hole92of the nearest diagonal member601and arranged in such a manner as to intersect the nearest diagonal member601. Although unillustrated, a reinforcement continuous member472is inserted in the through hole92of the nearest diagonal member602and arranged in such a manner as to intersect the nearest diagonal member602. A reinforcement continuous member473is inserted in the through hole92of the nearest diagonal member603and arranged in such a manner as to intersect the nearest diagonal member603. A reinforcement continuous member474is inserted in the through hole92of the nearest diagonal member604and arranged in such a manner as to intersect the nearest diagonal member604.

As described above, in the fifth embodiment shown inFIG.23, each of the nearest diagonal members601to604is inserted in the through hole91of the corresponding reinforcement continuous member47and arranged in such a manner as to intersect the reinforcement continuous member47. Besides, in the modification shown inFIG.25, the reinforcement continuous member47is inserted in the through hole92of the corresponding nearest diagonal member and arranged in such a manner as to intersect the nearest diagonal member. Therefore, for instance, as shown inFIGS.23and25, the end of the nearest diagonal member601is arrangeable nearer to the connector75A than the end of sub-reinforcement part451. This arrangement achieves a smaller gap between the end of the nearest diagonal member601and the connector75A (specifically, a pin insertion hole of the connector75A). More specifically, in the sideview shown in each ofFIG.23andFIG.25, this arrangement can achieve, for example, a shorter distance G between an intersection of a central axis of the first main member51and a central axis of the nearest diagonal member601, and a center of the pin insertion hole of the connector75A. Accordingly, an effect of the improved buckling strength is obtainable by the reinforcement part40and the sub-reinforcement part45in the coupling unit and therearound. Additionally, the aforementioned triangular configuration (lattice configuration) or a configuration similar to the lattice configuration in the coupling unit and therearound can exert an effect of suppressing lowering in the buckling strength.

Each of the nearest diagonal members601to604and the reinforcement continuous member47in the fifth embodiment and the modification thereof has a cross-section being continuous from the one end to the another end thereof without being divided. This configuration can effectively transmit a load from the one end to the another end of each of the nearest diagonal members601to604and the reinforcement continuous member47, or from the another end to the one end thereof, and further easily ensure the stiffness.

Besides, as shown inFIG.23andFIG.25, the configuration where one of the members is inserted in the through hole91or the through hole92of the other of the members can avoid an increase in the number of components, and further suppress occurrence of relative positional displacement between each of the nearest diagonal members601to604and the reinforcement continuous member47corresponding to the nearest diagonal member.

In the fifth embodiment shown inFIG.23, each of the nearest diagonal members601to604has a substantially uniform cross-section from the one end to the another end thereof. This configuration can further effectively transmit a load acting on, for example, the nearest diagonal member601to the first main member51and the connector75A near the first main member in a work performed by the working machine.

In the modification shown inFIG.25, the reinforcement continuous member47has a substantially uniform cross-section from the one end to the another end thereof. This configuration can suppress occurrence of a strain (e.g., welding strain) in the reinforcement continuous member47in manufacturing of the lattice structure.

Lattice Structure According to Sixth Embodiment

FIG.27is a perspective view of a main portion of a lattice structure according to a sixth embodiment, andFIG.28is a sideview thereof. A region occupied by the main portion shown in each ofFIG.27andFIG.28in the lattice structure according to the sixth embodiment corresponds to the portion in the framed box XVI inFIG.14.

The lattice structure according to the sixth embodiment includes four main members51to54, a plurality of connectors75A,75B, a plurality of diagonal members60, and a plurality of reinforcement parts40. As shown inFIGS.27and28, the first main member51has one end to which the male connector75B is connected and another end to which the female connector75A (not shown) is connected.

The reinforcement parts40in the sixth embodiment include, in the same manner as in the third embodiment shown inFIG.14, a reinforcement part401, a reinforcement part402, a reinforcement part403, and a reinforcement part404. These reinforcement parts401to404are respectively arranged at one end of the lattice structure32in a longitudinal direction thereof and another end of the lattice structure32in the longitudinal direction thereof. Each of the reinforcement parts40in the sixth embodiment is a linearly extending pipe (reinforcement pipe) in the same manner as in the third embodiment shown inFIG.14. However, each of the reinforcement parts40may be, for example, a member having a prism-shape, or a shaped steel member, such as an H-steel member and a channel steel member. Moreover, each of the reinforcement parts40may be a solid member.

A basic configuration of the lattice structure according to the sixth embodiment shown inFIG.27andFIG.28is similar to that of the lattice structure32) according to the third embodiment shown inFIG.14toFIG.17. Hereinafter, the differences between the sixth embodiment and the third embodiment will be mainly described.

Diagonal Member

Each of the diagonal members60linearly extends so as to be inclined with respect to the longitudinal direction of the lattice structure according to the sixth embodiment as well. Each of the diagonal members60is made of a single pipe except nearest diagonal members601to604to be described below. Each of the diagonal members60has one end in a longitudinal direction (axial direction) thereof and another end opposite the one end in the longitudinal direction. Each diagonal member60connects two adjacent main members among the four main members with each other. The diagonal members60include the plurality of nearest diagonal members601to604in the same manner as in the third embodiment.

Nearest Diagonal Member

The four nearest diagonal members601to604are located near one end of a lattice structure32in the longitudinal direction thereof and near another end of the lattice structure32in the longitudinal direction thereof. Each ofFIG.27andFIG.28illustrates only the nearest diagonal member601while omitting the illustration of the remaining nearest diagonal members602to604.

In the sixth embodiment, each of the nearest diagonal members601to604includes a diagonal member main body60D and an interposition member60E. The diagonal member main body60D is a member linearly extending from one main member50of the two adjacent members50toward the other main member50of the two adjacent members. The interposition member60E is interposed between the corresponding diagonal member main body60D and the other main member50. The diagonal member main body60D is, for example, a linearly extending single pipe, but may be a linearly extending solid member. Alternatively, the diagonal member main body60D may be a linearly extending plate-like member, or a linearly extending shaped steel member, such as an H-steel member and a channel steel member.

The interposition member60E has an interposition member main body620, a diagonal member main body connection part61, a reinforcement connection part62, and a main mber connection part63. The interposition member main body620has, for example, a triangular shape in a sideview as shown inFIG.28, but the shape of the interposition member main body620is not limited to the triangular shape. The interposition member main body620is, for example, a plate-like member, but may be, for example, a shaped steel member, such as an H-steel member and a channel steel member, or a pipe. One end of the corresponding diagonal member main body60D is connected to the diagonal member main body connection part61. One end of the corresponding reinforcement part40is connected to the reinforcement connection part62. The main member connection part63is connected to the other main member50.

A connection or joining way, e.g., welding, is used to connect or join the diagonal member main body connection part61and the one end of the diagonal member main body60D to each other, connect or join the reinforcement connection part62and the one end of the reinforcement part40to each other, and connect or join the main member connection part63and the main member50to each other, but the connection or joining way is not limited to the welding.

For instance, the nearest diagonal member601includes, as shown inFIG.27andFIG.28, a diagonal member main body60D extending from the second main member52toward the first main member51, and an interposition member60E interposed between the diagonal member main body60D and the first main member51. The main member connection part63of the nearest diagonal member601is connected to a portion of the main member51that is adjacent to the connector75B. The diagonal member main body60D of the nearest diagonal member601has one end connected to the diagonal member main body connection part61of the nearest diagonal member601. The reinforcement part401has one end connected to the reinforcement connection part62of the nearest diagonal member601.

Although unillustrated, each of the nearest diagonal members602to604has the same configuration as the nearest diagonal member601. The nearest diagonal member602includes a diagonal member main body60D extending from the third main member53toward the second main member52, and an interposition member60E interposed between the diagonal member main body60D and the second main member52. The main member connection part63of the nearest diagonal member602is connected to a portion of the second main member52that is adjacent to the connector75B. The diagonal member main body60D of the nearest diagonal member602has one end connected to the diagonal member main body connection part61of the nearest diagonal member602. The reinforcement part402has one end connected to the reinforcement connection part62of the nearest diagonal member602.

Similarly, the nearest diagonal member603includes a diagonal member main body60D extending from the fourth main member54toward the third main member53, and an interposition member60E interposed between the diagonal member main body60D and the third main member53. The main member connection part63of the nearest diagonal member603is connected to a portion of the third main member53that is adjacent to the connector75B. The diagonal member main body60D of the nearest diagonal member603has one end connected to the diagonal member main body connection part61of the nearest diagonal member603. The reinforcement part403has one end connected to the reinforcement connection part62of the nearest diagonal member603.

The nearest diagonal member604includes a diagonal member main body60D extending from the first main member51toward the fourth main member54, and an interposition member60E interposed between the diagonal member main body60D and the fourth main member54. The main member connection part63of the nearest diagonal member604is connected to a portion of the fourth main member54that is adjacent to the connector75B. The diagonal member main body60D of the nearest diagonal member604has one end connected to the diagonal member main body connection part61of the nearest diagonal member604. The reinforcement part404has one end connected to the reinforcement connection part62of the nearest diagonal member604.

In the sixth embodiment, each of the nearest diagonal members includes the interposition member60E having the three connection parts61to63. Therefore, as shown inFIG.28, this configuration achieves, for example, a smaller gap between the end of the nearest diagonal member601(specifically, the end of the interposition member60E) and the connector75B (specifically, a pin insertion hole of the connector75B). More specifically, in the sideview shown inFIG.28, this configuration can achieve, for example, a shorter distance G between an intersection of a central axis of the first main member51and a central axis of the diagonal member main body60D of the nearest diagonal member601, and a center of the pin insertion hole of the connector75B. Accordingly, an effect of the improved buckling strength is obtainable by the reinforcement part401in the coupling unit and therearound. Additionally, the aforementioned triangular configuration (lattice configuration) or a configuration similar to the lattice configuration in the coupling unit and therearound can exert an effect of suppressing lowering in the buckling strength.

The summary of the sixth embodiment is described heretofore, and the configuration in the sixth embodiment will be described below in more detail. Hereinafter, the nearest diagonal member601will be mainly described, but the remaining nearest diagonal members602to604have the same configuration.

As shown inFIG.27andFIG.28, the interposition member main body620of the interposition member60E has a diagonal member continuous part65being continuous from the diagonal member main body connection part61to the first main member51in a direction parallel to a longitudinal direction of the diagonal member main body60D. The diagonal member continuous part65has a leading end connected to the first main member51. In this manner, a load acting on the diagonal member main body60D of the nearest diagonal member601in a work performed by the working machine is continuously and effectively transmittable to the first main member51and the connector75B therearound via the diagonal member continuous part65of the interposition member60E.

Besides, the interposition member main body620of the interposition member60E further has a reinforcement continuous part66being continuous from the reinforcement connection part62to the first main member51in a direction parallel to a longitudinal direction (exemplary first specific direction) of the reinforcement part401. In this manner, a load acting on the reinforcement part401in a work performed by the working machine is continuously and effectively transmittable to the first main member51via the reinforcement continuous part66of the interposition member60E. The reinforcement continuous part66has a leading end connected to the first main member51at a position farther away from the connector75B than the leading end of the diagonal member continuous part65in the longitudinal direction of the first main member51.

The interposition member main body620of the interposition member60E further has a bridge part67extending along the first main member51for bridging the leading end of the diagonal member continuous part65and the leading end of the reinforcement continuous part66. The bridge part67provided in this manner can improve the stiffness of the interposition member60E.

The interposition member main body620has a hole68H defined by the diagonal member continuous part65, the reinforcement continuous part66, and the bridge part67thereamong. Specifically, the interposition member60E has the diagonal member continuous part65, the reinforcement continuous part66, and the bridge part67in necessary portions in view of the load transmission and stiffness improvement, and further has the hole68H in view of the weight reduction.

Moreover, as shown inFIG.27andFIG.28, the diagonal member main body connection part61has a welding surface61S which is flat for welding the one end of the diagonal member main body60D, and the reinforcement connection part62has a welding surface62S which is flat for welding the one end of the reinforcement part401. This configuration can more effectively improve the operability of the welding operation and improve the welding quality than a configuration with a welding surface having a curving shape, such as the side surface of a pipe.

For instance, Japanese unexamined patent publication No. SHO 58-65850 discloses a truss structure joint. The truss structure joint is aimed at joining a main pipe and a branch pipe of the truss structure to each other, and has a plurality of bulge parts for welding the branch pipe thereto, a part of or whole of the bulge parts being linearly connected to each other. As shown in FIG. 6 of Japanese unexamined patent publication No. SHO 58-65850, each of the bulge parts has a space inside, and thus the bulge part to which one end of the pipe is connected does not necessarily have high stiffness.

In contrast, in the embodiment, each of the diagonal member main body connection part61and the reinforcement connection part62is made of a plate-like member (member having a flat-plate shape), and is connected to the interposition member main body620. This configuration is advantageous in the stiffness in terms of no space between each of the diagonal member main body connection part61and the reinforcement connection part62, and the interposition member main body620.

Moreover, the truss structure joint in Japanese unexamined patent publication No. SHO 58-65850 that includes the bulge parts each having the complicated shape faces difficulty to manufacture so that a central axis of the branch pipe intersects a central axis of the main pipe. Furthermore, the truss structure joint gradually curves as a portion to be welded to the main pipe is longer in the longitudinal direction and in the cross-sectional direction of the main pipe, and accordingly the workability of the welding becomes worse. As a result, a problem of a welding strain is likely to occur. From these perspectives, it is difficult to manufacture the truss structure joint so that the central axis of the branch pipe intersects the central axis of the main pipe.

In contrast, in the sixth embodiment shown inFIG.27andFIG.28, the main member connection part63of the interposition member60E and the main member50define a straight connection portion therebetween, and the one end of the diagonal member main body60D is welded to the welding surface61S which is flat and the one end of the reinforcement part401is welded to the welding surface62S which is flat. Accordingly, the welding is easily executable, and the problem of the welding strain is unlikely to occur. Consequently, a configuration for the aforementioned smaller distance G (the distance G between the intersection of the central axis of the first main member51and the central axis of the nearest diagonal member601, and the center of the pin insertion hole of the connector75B) is accurately attainable.

First Modification

FIG.29is a sideview showing components of a lattice structure according to a first modification of the sixth embodiment. In the first modification shown inFIG.29, a diagonal member main body connection part61has a welding surface61S mostly perpendicular or substantially perpendicular to a longitudinal direction of a diagonal member main body60D. This configuration can further improve the operability of the welding operation and improve the welding quality.

Second Modification

FIG.30is a sideview of a portion of a lattice structure according to a second modification of the sixth embodiment. In the second modification shown inFIG.30, a diagonal member main body connection part61and a reinforcement connection part62are formed of an integrally continuous member. In this ease, a welding operation of welding the diagonal member main body connection part61and the reinforcement connection part62formed of the integrally continuous member to an interposition member main body620can be continuously performed, and accordingly, the operability of the welding operation is improvable. Furthermore, such continuous welding suppresses remaining of an unwelded portion which has been left unwelded, and hence the welding quality is improvable.

Third Modification

FIG.31is a sideview showing components of a lattice structure according to a third modification of the sixth embodiment. In the third modification shown inFIG.31, a diagonal member main body connection part61has a welding surface61S mostly perpendicular or substantially perpendicular to a longitudinal direction of a diagonal member main body60D, and the diagonal member main body connection part61and a reinforcement connection part62are formed of an integrally continuous member. In the third modification, the welding surface61S is substantially perpendicular to the longitudinal direction of the diagonal member main body60D, and a welding surface62S is substantially perpendicular to a longitudinal direction of a reinforcement part40. This configuration can further improve the workability of the welding operation and further improve the welding quality.

Fourth Modification

FIG.32is a perspective view of a portion of a lattice structure according to a fourth modification of the sixth embodiment, andFIG.33is a sideview thereof. Although the main member connection part63of the interposition member60E is joined to an outer peripheral surface of the main member50through welding in the embodiment shown inFIG.27, a main member connection part63of an interposition member60E in the fourth modification shown inFIG.32andFIG.33is connected to a main member50in the following manner.

As shown inFIG.32andFIG.33, a first main member51has an insertion part63hhaving at least one of a groove and a hole in which a portion of the interposition member60E is inserted. The insertion part63hmay be, for example, a through hole penetrating the first member51in a radial direction thereof, or a groove recessed in a portion on an outer periphery of the first main member51in the radial direction thereof.

The main member connection part63of the interposition member60E is fixedly attached to the first main member51by using a connection or joining way, e.g., welding, in a state where at least a portion of the main member connection part63is inserted in the insertion part63h.

In the fourth modification, the interposition member60E is fixedly attachable to the first main member51in the state where at least the portion of the main member connection part63of the interposition member60E is inserted in the insertion part63H. This configuration facilitates a positioning operation of deciding relative positions between the first main member51and the interposition member60E in the fixing and attaching operation, and accordingly improve accuracy of the relative positions and further improve the operability of the fixing and attaching operation.

In the fourth modification, the main member connection part63of the interposition member60E is weldable and fixedly attachable to the opposite portions of the main member51(upper portion and lower portion of the first main member51inFIG.33) in the radial direction thereof in the state of being inserted in the insertion part63hof the first main member51. In this case, the integrality of the first main member51and the interposition member60E is further increased, resulting in further improvement of the strength.

Lattice Structure According to Seventh Embodiment

FIG.34is a perspective view of a portion of a lattice structure according to a seventh embodiment, andFIG.35is a sideview thereof. A region occupied by a main portion shown in each ofFIG.34andFIG.35in the lattice structure according to the seventh embodiment corresponds to the portion in the framed box XVI inFIG.14.

A basic configuration of the lattice structure according to the seventh embodiment shown is similar to that of the lattice structure according to the sixth embodiment shown inFIG.27andFIG.28. Accordingly, hereinafter, the differences between the lattice structure according to the seventh embodiment between the lattice structure according to the sixth embodiment will be mainly described. The main differences are seen in the configuration of an interposition member60E. More details will be described below.

In the lattice structure according to the seventh embodiment shown inFIG.34andFIG.35, the interposition member60E has an interposition member main body620, a diagonal member main body connection part61, a reinforcement connection part62, and a main member connection part63, in the same manner as in the sixth embodiment. The interposition member main body620has a diagonal member continuous part65, a reinforcement continuous part66, and a first bridge part671.

The diagonal member continuous part65is continuous from the diagonal member main body connection part61to a first main member51in a direction parallel to a longitudinal direction of a diagonal member main body60D. The diagonal member continuous part65has a leading end connected to the first main member51. The reinforcement continuous part66is continuous from the reinforcement connection part62to the diagonal member continuous part65in a direction parallel to a longitudinal direction of a reinforcement part40. The reinforcement continuous part66has a leading end connected to the diagonal member continuous part65. The first bridge part671is located closer to a second main member52(closer to the reinforcement connection part62inFIG.35) than a specific position where the leading end of the reinforcement continuous part66is connected to the diagonal member continuous part65for bridging the diagonal member continuous part65and the reinforcement continuous part66.

In the seventh embodiment, a load acting on the diagonal member main body60D of a nearest diagonal member601in a work performed by the working machine is continuously and effectively transmittable to the first main member51and a connector75B adjacent thereto via the diagonal member continuous part65of the interposition member60E. Moreover, a load acting on the reinforcement part40is continuously and effectively transmittable to the first main member51via the reinforcement continuous part66of the interposition member60E. Furthermore, the first bridge part671bridging the diagonal member continuous part65and the reinforcement continuous part66can improve the stiffness of the interposition member60E.

In the seventh embodiment, the interposition member main body620of the interposition member60E further has a second bridge part672and a third bridge part673. The second bridge part672is located farther away from the connector75B than the leading end of the reinforcement continuous part66in the longitudinal direction of the first main member51for bridging the diagonal member continuous part65and the first main member51. The third bridge part673extends along the first main member for bridging the leading end of the diagonal member continuous part65and a leading end of the second bridge part672(where the second bridge part672is connected to the first main member51). The bridge parts672,673provided in this manner further enhances the stiffness of the interposition member60E.

In the seventh embodiment, the interposition member main body620has a hole681H defined by the diagonal member continuous part65, the reinforcement continuous part66, and the first bridge part671thereamong. Specifically, the interposition member60E has the diagonal member continuous part65, the reinforcement continuous part66, and the first bridge part671in necessary portions in view of improvement in the load transmission and stiffness, and further has the hole681H in view of the weight reduction. Additionally, the interposition member main body620has a hole682H defined by the diagonal member continuous part65, the second bridge part672, and the third bridge part673thereamong. Specifically, the interposition member60E has the diagonal member continuous part65, the second bridge part672, and the third bridge part673in necessary portions in view of improvement in the load transmission and stiffness, and further has the hole682H in view of the weight reduction.

Although the diagonal member continuous part65, the reinforcement continuous part66, and the first bridge part671in the interposition member main body620of the interposition member60E form a triangular shape (inverted triangular shape) in the sideview shown inFIG.35in the seventh embodiment, the formed shape is not limited to the triangular shape.

First Modification

FIG.36is a perspective view of a portion of a lattice structure according to a first modification of the seventh embodiment, andFIG.37is a sideview thereof. In the first modification shown inFIG.36andFIG.37, a diagonal member main body connection part61and a reinforcement connection part62are formed of an integrally continuous member. The diagonal member main body connection part61has a welding surface61S mostly perpendicular or substantially perpendicular to a longitudinal direction of a diagonal member main body60D.

Second Modification

FIG.38is a sideview of a portion of a lattice structure according to a second modification of the seventh embodiment. The second modification of the seventh embodiment has a connection or joining configuration similar to that of the fourth modification of the sixth embodiment shown inFIG.32andFIG.33.

As shown inFIG.38, a first main member51has an insertion part63hhaving at least one of a groove and a hole in which a portion of an interposition member60E is inserted. The insertion part63hmay be, for example, a through hole penetrating the first member51in a radial direction thereof, or a groove recessed in a portion on an outer periphery of the first main member51in the radial direction thereof. The interposition member60E has a main member connection part63fixedly attached to the first main member51by using a connection or joining way, e.g., welding, in a state where at least a portion of the main member connection part63is inserted in the insertion part63h.

Other Modifications

Although the crane is shown as a working machine in the examples of the embodiments, the working machine of the present invention is not limited to the crane, and any other working machine is adaptable as long as the machine includes a lattice structure.

Although the lattice structure serves as a member constituting a portion of the boom3of the working machine in the examples of the embodiments, the lattice structure according to the present invention is adaptable to a member constituting another portion of the working machine, such as the jib4, and the struts6,7as well.

Although the lower traveling body1serves as the base body in the examples of the embodiments, the base body is not limited thereto. The base body may not travel on the ground or may be fixed to the ground.

Although the crane100serving as the working machine includes the jib4, the mast5, and the struts6,7in the embodiments, the present invention is adoptable for a working machine excluding the jib4, the mast5, and the structs6,7.

Although the main members50composing a portion of each of the lattice structures32,33according the embodiments are arranged in parallel to each other in their respective axial directions, the arrangement is not limited thereto. The main members in the present invention cover main members with their respective axial directions which are not parallel to each other like a part of the main members50constituting each of the lattice structures31,34(boom members31,34) according to the embodiments. In other words, the main members may be arranged in such a posture that at least one of the main members is inclined in an axial direction thereof at an angle to the longitudinal direction of the lattice structure, e.g., in such a manner that the entirety of the lattice structure forms a pyramid-like shape or a truncated cone-like shape.

Each of the main member50, the diagonal member60, and the reinforcement part40may be a pipe, but is not limited thereto. At least one of the main member50, the diagonal member60, and the reinforcement part40may be made of, for example, a solid rod-like member, a plate-like member, or a cylindrical member, such as a shaped steel member.

The working machine according to the embodiments includes the mast5as shown inFIG.1, but the configuration of the working machine is not limited to this aspect. The working machine may include a gantry in place of the mast5. Alternatively, the working machine may include both the mast5and the gantry.

The working machine according to the embodiments includes the plurality of winches mounted on the upper slewing body2, but the arrangement of the winches is not limited to this aspect. At least one of the winches may be mounted on a boom.

The bridge part67is excludable in the sixth embodiment. This exclusion can contribute to weight reduction in the interposition member60E and reduction in the welding portion between the first main member51and the interposition member60E.

In the seventh embodiment, at least one of the first bridge part671, the second bridge part672, and the third bridge part673may be excludable. The exclusion can contribute to weight reduction in the interposition member60E. Moreover, exclusion of the third bridge part673can lead to reduction in the welding portion between the first main member51and the interposition member60E.

As described heretofore, provided are a lattice structure and a working machine including the same, the lattice structure including a reinforcement part for suppressing lowering in buckling strength in a coupling unit for coupling two lattice structures to each other and therearound, and being capable of suppressing an increase in a distance between ends of two adjacent diagonal members nearest to the coupling unit.

Provided is a lattice structure constituting a portion of a working machine and detachably couplable to another lattice structure adjacent to the lattice structure. The lattice structure includes: a plurality of main members extending along a longitudinal direction of the lattice structure and arranged at intervals in a direction perpendicular to the longitudinal direction; a plurality of diagonal members each extending so as to be inclined with respect to the longitudinal direction, each of the diagonal members connecting two main members among the plurality of main members with each other; a plurality of connectors respectively connected to ends of the main members in the longitudinal direction thereof; and at least one reinforcement part. The main members include a first main member and a second main member. The connectors include a first connector connected to an end of the first main member and a second connector connected to an end of the second main member. The diagonal members include a plurality of first diagonal members connecting the first main member and the second main member with each other, the first diagonal members including a first nearest diagonal member located nearest to the first connector. The at least one reinforcement part includes a first reinforcement part extending from the first nearest diagonal member to the second main member or the second connector in a first specific direction for connecting the first nearest diagonal member, and the second main member or the second connector with each other.

The lattice structure where the first reinforcement part is connected to the first nearest diagonal member eliminates the need to arrange the end of the first reinforcement part between the end of the nearest diagonal member and the first connector. Accordingly, the one end of the first nearest diagonal member can be nearer to the first connector. This configuration, even including the first reinforcement part, can suppress an increase in the distance between the ends of the two diagonal members, Le_, the distance between the end of the nearest diagonal member of the lattice structure and the end of the nearest diagonal member of the another lattice structure. As a result, an effect of the improved buckling strength is obtainable by the first reinforcement part in the coupling unit and therearound. Additionally, the aforementioned triangular configuration (lattice configuration) or a configuration similar to the lattice configuration in the coupling unit and therearound can exert an effect of suppressing lowering in the buckling strength.

In the lattice structure, the first nearest diagonal member preferably has one end connected to the first connector and another end connected to the second main member so that the first nearest diagonal member connects the first main member and the second main member with each other.

In this aspect, the one end of the first nearest diagonal member is connected to the first connector. Thus, the first nearest diagonal member contributes to an ideal lattice structure in the coupling unit (specifically, a portion of the coupling unit corresponding to the first connector) between the lattice structure and the another lattice structure. This configuration can effectively suppress lowering in the stiffness of the lattice structure in the coupling unit and therearound.

In the lattice structure, the first specific direction is preferably perpendicular to the longitudinal direction of the lattice structure.

In this aspect, the longitudinal direction (first specific direction) of the first reinforcement part is perpendicular to the longitudinal direction of the lattice structure, and approximates to the direction in which the buckling deformation of the lattice structure may occur. Accordingly, the buckling strength is further effectively improved.

In the lattice structure, it is preferable that the main members further include a third main member and a fourth main member, the first main member and the second main member are respectively disposed, when the lattice structure is viewed in the longitudinal direction thereof, at positions corresponding to two adjacent vertices among four vertices of a quadrangular shape, and the third main member and the fourth main member are disposed at positions corresponding to remaining two vertices among the four vertices. The connectors preferably further include a third connector connected to an end of the third main member and a fourth connector connected to an end of the fourth main member. The diagonal members preferably include a plurality of second diagonal members connecting the third main member and the fourth main member with each other, the second diagonal members including a second nearest diagonal member located nearest to the third connector. The at least one reinforcement part preferably further includes a second reinforcement part extending from the second nearest diagonal member to the fourth main member or the fourth connector in a second specific direction for connecting the second nearest diagonal member, and the fourth main member or the fourth connector with each other.

In the aspect, the first member and the second main member respectively disposed at positions corresponding to the two adjacent vertices among the four vertices of the quadrangular shape are supported by the first nearest diagonal member and the first reinforcement part, and the third main member and the fourth main member disposed at positions corresponding to the remaining two vertices among the four vertices are supported by the second nearest diagonal member and the second reinforcement part. Accordingly, the portions of the lattice structure corresponding to the respective opposite sides of the quadrangular shape thereof are reinforced in a good balance.

In the lattice structure, the second nearest diagonal member preferably has one end connected to the third connector and another end connected to the fourth main member so that the second nearest diagonal member connects the third main member and the fourth main member with each other.

In this aspect, the one end of the second nearest diagonal member is connected to the third connector. Thus, the second nearest diagonal member contributes to the ideal lattice structure in the coupling unit (specifically, a portion of the coupling unit corresponding to the third connector) between the lattice structure and the another lattice structure. This configuration can further suppress lowering in the stiffness of the lattice structure in the coupling unit and therearound.

In the lattice structure, the second specific direction is preferably perpendicular to the longitudinal direction of the lattice structure.

In this aspect, the longitudinal direction (second specific direction) of the second reinforcement part is perpendicular to the longitudinal direction of the lattice structure, and approximates to the direction in which the buckling deformation of the lattice structure may occur. Accordingly, the buckling strength is further effectively improved.

The lattice structure preferably further includes a sub-reinforcement part for connecting the first main member and the first nearest diagonal member with each other.

The lattice structure according to this aspect includes the sub-reinforcement part for connecting the first embodiment and the first nearest diagonal member with each other in addition to the first reinforcement part for connecting the first nearest diagonal member, and the second main member or the second connector with each other. That is to say, the first reinforcement part and the sub-reinforcement part support the first nearest diagonal member at the opposite positions across the first nearest diagonal member. Therefore, in this aspect, the lattice structure more effectively suppresses the deformation of the first nearest diagonal member than a lattice structure including no sub-reinforcement part, and thus has further improved stiffness.

In the lattice structure, the sub-reinforcement part is preferably arranged at such a position as to overlap the first reinforcement part when the sub-reinforcement part is viewed in the first specific direction.

In this aspect, a load is effectively transmitted from the first reinforcement part to the sub-reinforcement part, and a load is effectively transmitted from the sub-reinforcement part to the first reinforcement part in a work performed by the working machine.

In the lattice structure, the sub-reinforcement part preferably extends from the first main member to the first nearest diagonal member in a direction parallel to the first specific direction.

In this aspect, the longitudinal direction of the sub-reinforcement part is parallel to the longitudinal direction (first specific direction) of the first reinforcement part. Hence, a load is further effectively transmitted from the first reinforcement part to the sub-reinforcement part, and a load is further effectively transmitted from the sub-reinforcement part to the first reinforcement part in a work performed by the working machine. Particularly, the longitudinal direction of the sub-reinforcement part is more preferably perpendicular to the longitudinal direction of the lattice structure. In this case, the longitudinal direction of the sub-reinforcement part approximates to the direction in which the buckling deformation of the lattice structure may occur. Accordingly, the buckling strength is further effectively improved.

In the lattice structure, the first nearest diagonal member may be a continuous member continuously extending from the first main member or the first connector to the second main member, the first reinforcement part may have one end and another end in the first specific direction, and the one end being connected to the first nearest diagonal member and the another end being connected to the second main member or the second connector. The sub-reinforcement part may have one end connected to the first main member and another end connected to the first nearest diagonal member.

In this aspect, connecting the first reinforcement part and the sub-reinforcement part to the first nearest diagonal member that is the continuous member attains arrangement of the end of the first nearest diagonal member nearer to the first connector than the sub-reinforcement part. This arrangement achieves a smaller gap between the end of the first nearest diagonal member and the first connector (specifically, the pin insertion hole of the first connector). Accordingly, in the aspect, an effect of the improved buckling strength is obtainable by the first reinforcement part and the sub-reinforcement part in the coupling unit and therearound. Additionally, the aforementioned triangular configuration (lattice configuration) or a configuration similar to the lattice configuration in the coupling unit and therearound can exert an effect of suppressing lowering in the buckling strength.

In this aspect, the first nearest diagonal member that is the continuous member as described above can be made of a single member. A first nearest diagonal member made of a single member can more smoothly transmit a load at the first nearest diagonal member than a first nearest diagonal member composed of a plurality of members connected to each other. This can further effectively improve the stiffness of the lattice structure.

A load acting on each of the first reinforcement part and the sub-reinforcement part is highly likely to be smaller than a load acting on the first nearest diagonal member in a work performed by the working machine. Hence, an outer diameter of each of the first reinforcement part and the sub-reinforcement part can be made smaller than an outer diameter of the first nearest diagonal member. In this case, weight reduction in the lattice structure is achievable. Furthermore, in this case, each of the first reinforcement part and the sub-reinforcement part having the relatively small diameter is easily connectable to the first nearest diagonal member having the relatively large diameter.

In the lattice structure, for example, the sub-reinforcement part may be made of a pipe. The sub-reinforcement part may be made of at least a plate-like member, a shaped steel member, or a member having a box shape.

A sub-reinforcement part made of at least a plate-like member is easier to manufacture and can lead to greater cost reduction than a sub-reinforcement part made of a pipe. For instance, a sub-reinforcement part made of a shaped steel member, such as an H-steel member and a channel steel member, can more effectively improve the strength than the sub-reinforcement part made of the plate-like member. A sub-reinforcement part made of a member having a box shape can more effectively improve the strength and achieve greater weight reduction than the sub-reinforcement part made of the plate-like member.

In the lattice structure, the first reinforcement part may constitute a portion of a continuous member continuously extending from the first main member to the second main member or the second connector in the first specific direction, the portion including an end of the continuous member that is connected to the second main member or the second connector. The sub-reinforcement part may constitute another portion of the continuous member, the another portion including another end of the continuous member that is connected to the first main member. The first nearest diagonal member may include: an intermediate section included in the continuous member and located between the first reinforcement part and the sub-reinforcement part; a first member connected to the intermediate section and extending from the intermediate section to the first main member or the first connector; and a second member connected to the intermediate section and extending from the intermediate section to the second main member.

In this aspect, the first reinforcement part constitutes a portion of the continuous member and the sub-reinforcement part constitutes another portion of the continuous member. Further, the first nearest diagonal member includes the intermediate section included in the continuous member, and the first member and the second member each connected to the inter mediate section. Therefore, the end of the first nearest diagonal member is arrangeable nearer to the first connector than the sub-reinforcement part. This arrangement achieves a smaller gap between the end of the first nearest diagonal member and the first connector (specifically, the pin insertion hole of the first connector). Accordingly, in the aspect, an effect of the improved buckling strength is obtainable by the first reinforcement part and the sub-reinforcement part in the coupling unit and therearound. Additionally, the aforementioned triangular configuration (lattice configuration) or a configuration similar to the lattice configuration in the coupling unit and therearound can exert an effect of suppressing lowering in the buckling strength.

Moreover, in this aspect, adoption of the configuration including the first member and the second member each connected to the intermediate section of the continuous member succeeds in forming the continuous member including the reinforcement part and the sub-reinforcement part by a single member. A continuous member made of a single member can more effectively suppress a decrease in a dimensional accuracy of the continuous member in the longitudinal direction thereof than a continuous member composed of a plurality of members connected to each other. This configuration can easily ensure accuracy of a distance between the first connector and the second connector, specifically, a distance between the pin insertion hole of the first connector and the pin insertion hole of the second connector.

Furthermore, in this aspect, the first nearest diagonal member is formed by connecting the first member and the second member to the intermediate section. Here, the length of each of the three elements can be made shorter than an entire length of the first nearest diagonal member. The first nearest diagonal member having this configuration is more advantageous in the buckling strength than a first nearest diagonal member made of a single member. Accordingly, the weight reduction can be also aimed by decreasing a cross-sectional area of the first nearest diagonal member.

In the lattice structure, the first member is preferably arranged at such a position as to overlap the second member when the first member is viewed in a longitudinal direction of the second member.

In this aspect, a load is effectively transmitted from the first member to the second member, and a load is effectively transmitted from the second member to the first member in a work performed by the working machine.

In the lattice structure, a longitudinal direction of the first member is preferably parallel to the longitudinal direction of the second member.

In this aspect, a load is further effectively transmitted from the first member to the second member, and a load is further effectively transmitted from the second member to the first member in a work performed by the working machine.

In the lattice structure, for example, the first member may be made of a pipe. The first member may be made of at least a plate-like member, a shaped steel member, or a member having a box shape.

A first member made of at least a plate-like member is easier to manufacture and leads to greater cost reduction than a first member made of a pipe. A first member made of a shaped steel member, such as an H-steel member and a channel steel member, can more effectively improve the strength than the first member made of the plate-like member. A first member made of a member having a box shape can more effectively improve the strength and achieve greater weight reduction than the first member made of the plate-like member.

In the lattice structure, the first nearest diagonal member is preferably a continuous member continuously extending from the first main member or the first connector to the second main member. The first reinforcement part preferably constitutes a portion of a reinforcement continuous member continuously extending from the first main member to the second main member or the second connector in the first specific direction, the portion of the reinforcement continuous member extending from the first nearest diagonal member to the second main member or the second connector. The sub-reinforcement part preferably constitutes another portion of the reinforcement continuous member, the another portion of the reinforcement continuous member extending from the first main member to the first nearest diagonal member. One member of the reinforcement continuous member and the first nearest diagonal member preferably has a through hole penetrating the one member in a direction intersecting a longitudinal direction of the one member, and the other member of the reinforcement continuous member and the first nearest diagonal member is preferably inserted in the through hole and arranged to intersect the one member.

In this aspect, the other member is inserted in the through hole and arranged in such a manner as to intersect the one member. Thus, the end of the first nearest diagonal member is arrangeable nearer to the first connector than the sub-reinforcement part. This arrangement achieves a smaller gap between the end of the first nearest diagonal member and the first connector (specifically, the pin insertion hole of the first connector). Accordingly, in the aspect, an effect of the improved buckling strength is obtainable by the first reinforcement part and the sub-reinforcement part in the coupling unit and therearound. Additionally, the aforementioned triangular configuration (lattice configuration) or a configuration similar to the lattice configuration in the coupling unit and therearound can exert an effect of suppressing lowering in the buckling strength.

In this aspect, each of the first nearest diagonal member and the reinforcement continuous member has a cross-section being continuous from the one end to the another end thereof without being divided. This configuration can effectively transmit a load from the one end to the another end of each of the first nearest diagonal member and the reinforcement continuous member, or from the another end to the one end thereof, and further easily ensure the stiffness.

Besides, the configuration where the other member is inserted in the through hole formed in the one member can avoid an increase in the number of components, and further suppress occurrence of relative positional displacement between the first nearest diagonal member and the corresponding reinforcement continuous member. Specifically, for instance, in adoption of a configuration where the reinforcement continuous member has the through hole in which the first nearest diagonal member is inserted, the first nearest diagonal member can have a substantially uniform cross-section from the one end to the another end thereof. This configuration can more effectively transmit a load acting on the first nearest diagonal member to the first main member or the first connector in a work performed by the working machine. In contrast, in adoption of a configuration where the first nearest diagonal member has the through hole in which the reinforcement continuous member is inserted, the reinforcement continuous member can have a substantially uniform cross-section from the one end to the another end thereof. This configuration can suppress occurrence of a strain (e.g., welding strain) in the reinforcement continuous member in manufacturing of the lattice structure.

In the lattice structure, the first nearest diagonal member preferably includes: a diagonal member main body extending from the second main member toward the first main member and the first connector; and an interposition member interposed between the diagonal member main body and at least one of the first main member and the first connector, and having a portion connected to at least one of the first main member and the first connector. The interposition member preferably has a diagonal member main body connection part to which one end of the diagonal member main body is connected and a reinforcement connection part to which one end of the first reinforcement part is connected.

In this configuration, the interposition member having the three connection parts is provided. Specifically, the provided interposition member has: the connection part connected to at least one of the first main member and the first connector; the diagonal member main body connection part; and the reinforcement connection part. This configuration achieves a smaller gap between the end of the first nearest diagonal member (i.e., the end of the interposition member) and the first connector (specifically, the pin insertion hole of the first connector). Accordingly, in the aspect, an effect of the improved buckling strength is obtainable by the first reinforcement part and the sub-reinforcement part in the coupling unit and therearound. Additionally, the aforementioned triangular configuration (lattice configuration) or a configuration similar to the lattice configuration in the coupling unit and therearound can exert an effect of suppressing lowering in the buckling strength.

In the lattice structure, the interposition member preferably has a diagonal member continuous part being continuous from the diagonal member main body connection part to at least one of the first main member and the first connector in a direction parallel to a longitudinal direction of the diagonal member main body.

In this aspect, a load acting on the diagonal member main body of the first nearest diagonal member in a work performed by the working machine is continuously and effectively transmittable to the first main member or the first connector via the diagonal member continuous part of the interposition member.

In the lattice structure, the interposition member preferably has a reinforcement continuous part being continuous from the reinforcement connection part to the first main member in a direction parallel to a longitudinal direction of the first reinforcement part.

In this aspect, a load acting on the first reinforcement part in a work performed by the working machine is continuously and effectively transmittable to the first main member via the reinforcement continuous part of the interposition member.

In the lattice structure, the interposition member preferably has: a diagonal member continuous part being continuous from the diagonal member main body connection part to at least one of the first main member and the first connector in a direction parallel to a longitudinal direction of the diagonal member main body, and being configured to have a leading end connected to at least one of the first main member and the first connector; a reinforcement continuous part being continuous from the reinforcement connection part to the first main member in a direction parallel to a longitudinal direction of the first reinforcement part, and being configured to have a leading end connected to the first main member at a position farther away from the first connector than the leading end of the diagonal member continuous part in the longitudinal direction of the first main member; and a bridge part extending along the first main member for bridging the leading end of the diagonal member continuous part and the leading end of the reinforcement continuous part.

In this aspect, a load acting on the diagonal member main body of the first nearest diagonal member in a work performed by the working machine is continuously and effectively transmittable to the first main member or the first connector via the diagonal member continuous part of the interposition member. Moreover, a load acting on the first reinforcement part is continuously and effectively transmittable to the first main member via the reinforcement continuous part of the interposition member. Furthermore, the bridge part bridging the leading end of the diagonal member continuous part and the leading end of the reinforcement continuous part can prove the stiffness of the interposition member.

In the lattice structure, the interposition member preferably has: a diagonal member continuous part being continuous from the diagonal member main body connection part to at least one of the first main member and the first connector in a direction parallel to a longitudinal direction of the diagonal member main body, and being configured to have a leading end connected to at least one of the first main member and the first connector; a reinforcement continuous part being continuous from the reinforcement connection part to the diagonal member continuous part in a direction parallel to a longitudinal direction of the first reinforcement part, and being configured to have a leading end connected to the diagonal member continuous part; and a bridge part located closer to the second main member than a specific portion of the interposition member where the leading end of the reinforcement continuous part is connected to the diagonal member continuous part for bridging the diagonal member continuous part and the reinforcement continuous part.

In this aspect, a load acting on the diagonal member main body of the first nearest diagonal member in a work performed by the working machine is continuously and effectively transmittable to the first main member or the first connector via the diagonal member continuous part of the interposition member. Moreover, a load acting on the first reinforcement part is continuously and effectively transmittable to the first main member via the reinforcement continuous part of the interposition member. Furthermore, the bridge part bridging the diagonal member continuous part and the reinforcement continuous part can improve the stiffness of the interposition member.

In the lattice structure, the interposition member preferably further has a second bridge part located farther away from the first connector than the leading end of the reinforcement continuous part in the longitudinal direction of the first main member for bridging the diagonal member continuous part and the first main member.

In this aspect, the second bridge part further enhances the stiffness of the interposition member.

In the lattice structure, the interposition member preferably further has a third bridge part extending along the first main member for bridging the leading end of the diagonal member continuous part and a leading end of the second bridge part, the leading end of the second bridge part being connected to the first main member.

In this aspect, the third bridge part still further enhances the stiffness of the interposition member.

In the lattice structure, it is preferable that the diagonal member main body connection part has a welding surface which is flat for welding the one end of the diagonal member main body, and the reinforcement connection part has a welding surface which is flat for welding the one end of the first reinforcement part.

In this aspect, the configuration where the one end of the diagonal member main body and the one end of the first reinforcement part are connected to the diagonal member main body connection part and the reinforcement connection part respectively by a welding operation provides the following advantages. Specifically, in this aspect, the configuration can more effectively improve the operability of the welding operation and improve the welding quality than a configuration with a welding surface having a curving shape, such as the side surface of a pipe.

In the lattice structure, the diagonal member main body connection part and the reinforcement connection part are preferably formed of an integrally continuous member.

In this aspect, the diagonal member main body connection part and the reinforcement connection part are formed of an integrally continuous member. Therefore, the welding for welding these members can be continuously performed, and accordingly, the operability of the welding operation is improvable. Furthermore, such continuous welding suppresses remaining of an unwelded portion which has been left unwelded, and hence the welding quality is improvable.

In the lattice structure, the first main member may have an insertion part having at least one of a groove and a hole in which a portion of the interposition member is inserted, and the interposition member may be fixedly attached to the first main member in a state where the portion of the interposition member is inserted in the insertion part.

In this aspect, the interposition member is fixedly attachable to the first main member in the state where at least the portion of the interposition member is inserted in the insertion part. This configuration facilitates a positioning operation of deciding relative positions between the first main member and the interposition member in the fixing and attaching operation, and accordingly improve accuracy of the relative positions and further improve the operability of the fixing and attaching operation.

A provided working machine includes: a base body; an upper stewing body slewably mounted on the base body; and a boom rotatably attached to the upper stewing body and having the lattice structure described above and the another lattice structure adjacent to the lattice structure. Each of the connectors of the lattice structure is connected to a corresponding connector of the another lattice structure with a pin. The first specific direction in which the first reinforcement part extends is perpendicular to an axial direction of the pin.

In the working machine, the first specific direction in which the reinforcement part extends is perpendicular to the axial direction of the pin, and therefore the reinforcement part can effectively improve the buckling strength. Specifically, a mechanism that the buckling deformation is likely to occur in the coupling unit of the lattice structure and therearound will be described below. When the boom receives a compressive load in the longitudinal direction thereof, a specific main member of the lattice structure rotates about the pin relative to a corresponding main member of the another lattice structure in the coupling unit for coupling the lattice structure and the another structure to each other. This may cause the buckling deformation. In the aspect, the reinforcement part connects the nearest diagonal member, and the main member or the connector with each other in a posture with the first specific direction being perpendicular to the axial direction of the pin. The reinforcement part arranged in the aforementioned manner can effectively suppress such deformation of the main member of the lattice structure as to rotate about the pin relative to the main member of the another lattice structure when the boom receives the compressive load. Consequently, the buckling deformation is effectively suppressed.