Patent Description:
Concrete wave dissipating blocks having four leg portions extending from the barycentric position of a regular tetrahedron toward the respective vertexes, i.e., extending in respective different directions, conventionally provide strong interlocking force when piled up because of their unique shape. Since the energy of waves in rivers and seas can thus be effectively attenuated and dissipated, wave dissipating blocks are also called wave dissipating foundation blocks, blocks for dissipating waves, etc., and are used for bank protection and water use purposes.

However, when a work machine such as a crane hangs up and down a wave dissipating block, a plurality of wires generally need to be used due to the unique shape. In most cases, the wrapped plurality of wires are manually fastened and unfastened under the wave dissipating block (wire slinging operations (anchoring operations)). Since wave dissipating blocks are heavy in weight, the wires used are also heavy, and a lot of effort is needed to simply fasten and unfasten the wires manually. Moreover, wave dissipating blocks are often used in sites with poor footing, which is accompanied with a lot of danger to the workers. In particular, in piling up a plurality of wave dissipating blocks, instructions need to be issued by a worker on the wave dissipating block near ones to be situated lower. The surfaces of the wave dissipating blocks are slippery, and the working environment is unstable. Workers slipping or falling off are therefore likely, and a lot of accidents have occurred.

Under the circumstances above, various grapple-machines have heretofore been proposed. For example, to resolve the dangerous manual slinging operations, a grapple-machine according to Patent Literature <NUM> is configured to grab the junction of leg portions extending in three directions in a plan view by closing three holding members. In other words, Patent Literature <NUM> shows the configuration in which the vicinity of the barycentric portion of a wave dissipating block is grabbed, whereby the wave dissipating block can be stably grabbed and moved.

However, the grapple-machine described in Patent Literature <NUM> is sometimes unable to stably grab a wave dissipating block unless one of the leg portions is situated directly downward or directly upward and no obstacles are around the vicinity of the barycentric portion of the wave dissipating block. In other words, if wave dissipating blocks are restacked and moved several times or stocked in preparation for natural disasters, the wave dissipating blocks piled up can be difficult to grab near the barycentric portions. In such cases, the grapple-machine described in Patent Literature <NUM> may have difficulty in grabbing and moving the wave dissipating blocks.

Since Patent Literature <NUM> assumes a state where a wave dissipating block is situated with a leg portion directly upward as well, the grapple-machine needs to have a size such that an entire leg portion is embraced (for example, for a wave dissipating block of approximately <NUM> tons in weight and approximately <NUM> in height, the grapple-machine is approximately <NUM> tons in weight and approximately <NUM> in height). The grapple-machine according to Patent Literature <NUM> can thus be large and heavy in itself with respect to wave dissipating blocks.

The present invention has been achieved to solve the aforementioned problems, and an object thereof is to provide a small-sized lightweight wave dissipating block grapple-machine capable of grabbing and moving a wave dissipating block safely and more reliably without a dangerous manual slinging operation.

The present invention solves the aforementioned problems through the provision of a wave dissipating block grapple-machine that is supported by a work machine and can grab a wave dissipating block having a plurality of leg portions extending in respective different directions, the wave dissipating block grapple-machine including: a first holding mechanism and a second holding mechanism configured to radially hold respective two of the leg portions; and a base member that is rotatably supported by the work machine, the base member being configured to support the first holding mechanism and the second holding mechanism. The first holding mechanism includes a pair of first holding members that are rotatably supported by the base member and can grab one of the two leg portions by bringing their end portions close to each other, and a first driving device configured to drive the pair of first holding members to rotate, and the second holding mechanism includes a ring member having an adjustable inner diameter greater than or equal to a minimum outer diameter of the leg portion.

In the present invention, the first holding mechanism and the second holding mechanism that radially hold respective two of the leg portions of the wave dissipating block having the plurality of leg portions extending in respective different directions are provided. The wave dissipating block can thus be grabbed more reliably since the number of wave dissipating blocks in an orientation where two leg portions can be grabbed is considered to be greater than that of wave dissipating blocks in an orientation where the vicinity of the barycentric portion can be grabbed as described in the conventional art. Moreover, the first holding mechanism and the second holding mechanism can be configured to only radially hold respective two leg portions. Such a configuration can eliminate the need for a large holding mechanism to embrace an entire leg portion.

According to the present invention, a small-sized lightweight wave dissipating block grapple-machine capable of grabbing and moving a wave dissipating block safely and more reliably without a dangerous manual slinging operation can be provided.

An example of a first embodiment of the present invention will be described in detail below with reference to <FIG>.

A work machine <NUM>, a wave dissipating block grapple-machine <NUM>, and a wave dissipating block CB will initially be outlined with reference to <FIG>.

As shown in <FIG>, the work machine <NUM> is a crane truck with outriggers (may be an excavator, a crane mechanism installed on a barge, etc.), for example, and includes an arm body <NUM>, which is capable of changing its tilt angle, on a rotatable main body unit <NUM>. The arm body <NUM> is an extendable and contractible telescopic boom (may be a lattice boom), for example. A main wheel <NUM> is located at the end of the arm body <NUM>, and a main wire Mw hanging the wave dissipating block grapple-machine <NUM> is engaged with the main wheel <NUM> (the wave dissipating block grapple-machine <NUM> can thus rotate accordingly about the main wire Mw). Although not shown, a sub wheel is located at the end of the arm body <NUM>, and a sub wire Sw for changing the orientation of the wave dissipating block grapple-machine <NUM> is engaged with the sub wheel. Specifically, reducing the feed lengths of the main wire Mw and the sub wire Sw lifts up the wave dissipating block grapple-machine <NUM>. Increasing the feed lengths of the main wire Mw and the sub wire Sw lowers the wave dissipating block grapple-machine <NUM>. A relay wheel <NUM> that feeds fluid hoses (connected to fluid pressure inlets FI and fluid discharge outlets FO of driving mechanisms <NUM> to be described below) and electric cables (extending from a control unit CU, to be described below, to a first electric linear motion mechanism <NUM> and a second electric linear motion mechanism <NUM>) for driving the wave dissipating block grapple-machine <NUM> is rotatably supported on the arm body <NUM>.

As shown in <FIG>, the wave dissipating block CB is an oddly shaped concrete block having four leg portions LP extending from the barycentric position of a regular tetrahedron toward the respective vertexes, i.e., extending in respective different directions. Wave dissipating blocks CB typically do not include reinforcing bars in view of protection against corrosive degradation. Wave dissipating blocks CB can thus be broken into large pieces under local stress, and therefore need to be grabbed, transported, and installed with great care and precision without much stress, due partly to their large size. There are a total of <NUM> types or sizes of wave dissipating blocks CB in general use, ranging from <NUM> tons in weight (<NUM> in height) to <NUM> tons (<NUM> in height), with leg portions LP having substantially circular cross sections. Most wave dissipating blocks CB used on rivers are <NUM> tons or less (for example, <NUM> tons in weight and approximately <NUM> in height). A desired number of wave dissipating blocks CB of desired sizes are normally produced using forms near the construction site.

As shown in <FIG>, the wave dissipating block grapple-machine <NUM> is supported by the work machine <NUM>, and can grab a wave dissipating block CB. As shown in <FIG>, the wave dissipating block grapple-machine <NUM> includes an attachment unit <NUM>, a base member <NUM>, a first holding mechanism <NUM>, and a second holding mechanism <NUM>. The first holding mechanism <NUM> and the second holding mechanism <NUM> radially hold respective two of the four leg portions LP of the wave dissipating block CB. The base member <NUM> is rotatably supported by the work machine <NUM>, and supports the first holding mechanism <NUM> and the second holding mechanism <NUM>. In the present embodiment, wave dissipating blocks CB are assumed to be ones mainly usable on rivers. For example, for a wave dissipating block CB of <NUM> tons in weight and approximately <NUM> in height, the wave dissipating block grapple-machine <NUM> is less than <NUM> tons in weight and less than <NUM> in height (for example, for a wave dissipating block CB of <NUM> tons in weight and approximately <NUM> in height, the wave dissipating block grapple-machine <NUM> can be configured to be at most less than <NUM> tons in weight and less than <NUM> in height). Different wave dissipating block grapple-machines <NUM> are desirably used for respective sizes of wave dissipating blocks CB, whereas one size of wave dissipating block grapple-machine <NUM> can grab three or more adjoining sizes of wave dissipating blocks CB (for example, a wave dissipating block grapple-machine <NUM> intended for a wave dissipating block CB of <NUM> tons (<NUM> in height) can move five different sizes of wave dissipating blocks CB, including <NUM> tons (<NUM> in height), <NUM> tons (<NUM> in height), <NUM> tons (<NUM> in height), <NUM> tons (<NUM> in height), and <NUM> tons (<NUM> in height)).

Next, each of the components will be described in detail.

As shown in <FIG>, the attachment unit <NUM> is coupled to the base member <NUM>, and has a main attachment hole 112A to be supported by the main wire Mw and a sub attachment hole 112C to be supported by the sub wire Sw. The main attachment hole 112A is located on an extension of the main wire Mw to roughly overlap the barycenter of the wave dissipating block grapple-machine <NUM>. The sub attachment hole 112C is located at an end of an extending portion 112B extending in a direction orthogonal to the main wire Mw. The orientation of the wave dissipating block grapple-machine <NUM> can thus be changed by changing the feed length of the sub wire Sw (to decrease) with respect to that of the main wire Mw (in other words, the base member <NUM> is equipped with a changing member (i.e., extending portion 112B) for changing the positional relationship between the first holding mechanism <NUM> and the second holding mechanism <NUM> when the base member <NUM> is rotatably supported by the work machine <NUM>).

As shown in <FIG>, the base member <NUM> has a symmetrical structure because the first holding mechanism <NUM> and the second holding mechanism <NUM> have the same shape. The base member <NUM> includes a connection portion 114A, outside portions 114B, a split center portion 114C, split support portions 114D, rotation support portions 114E, and pressure portions 114F. The connection portion 114A is a plate-like member coupled to the attachment unit <NUM>. The outside portions 114B are plate-like members integrally disposed on both ends of the connection portion 114A in respective oblique directions (for example, tilted at approximately <NUM>° downward from a plane where the connection portion 114A is). The split center portion 114C and the two split support portions 114D are plate-like members integrally configured inside and orthogonal to the connection portion 114A and the two outside portions 114B, respectively. The split center portion 114C and the two split support portions 114D are also integrally connected. As shown in <FIG>, the connection portion 114A, the outside portions 114B, the split center portion 114C, and the split support portions 114D constitute two symmetrical cylindrical shapes surrounding linear motion mechanisms <NUM> and driving mechanisms <NUM> (in other words, the linear motion mechanisms <NUM> and the driving mechanisms <NUM> are built in the wave dissipating block grapple-machine <NUM>). The base member <NUM> thus has a structure less deformable even under a large external force. The rotation support portions 114E are integrated with the split support portions 114D, and rotatably support a pair of first holding members <NUM> and a pair of second holding members <NUM> on planes parallel to the outside portions 114B. With such a configuration, the cross section of the part of the leg portion LP held by the first holding mechanism <NUM> and the cross section of the part of the leg portion LP held by the second holding mechanism <NUM> both are flat planes, which intersect at approximately <NUM>° (angle α), i.e., an acute angle. Each rotation support portion 114E rotatably supports the pair of first holding members <NUM> (the pair of second holding members <NUM>) by sandwiching and pivotally supporting the pair of first holding members <NUM> (the pair of second holding members <NUM>) with the pressure portion 114F located on the outer side.

As shown in <FIG>, the first holding mechanism <NUM> includes the pair of first holding members <NUM> and a first driving device <NUM>. As shown in <FIG>, the second holding mechanism <NUM> is configured to be the same as the first holding mechanism <NUM>, and includes the pair of second holding members <NUM> and a second driving device <NUM>.

As shown in <FIG>, the pair of first holding members <NUM> is rotatably supported by the base member <NUM>, and can grab one of the two leg portions LP by bringing their end portions 118A close to each other. As shown in <FIG>, the first holding members <NUM> are plate-like members shaped so that the portions that make contact with the leg portion LP are curved to the shape of the leg portion LP. Contact portions <NUM> to direct make contact with the leg portion LP are provided with bar-like members having a substantially circular cross-sectional shape (the bar-like members may be formed of a cushioning material, such as rubber, and are replaceable). The pair of first holding member <NUM> can thus hold the leg portion LP without applying a local stress to the wave dissipating block CB and can prevent breakage of the leg portion LP, because of the edgeless structure. Upper ends 118B of the pair of first holding members <NUM> are both directly coupled to the ends of a linear motion mechanism <NUM> (to be described below). The pair of second holding members <NUM> has the same configuration as that of the pair of first holding members <NUM>, and a description thereof will thus be omitted. In particular, end portions 142A have the same configuration as that of the end portions 118A, and contact portions <NUM> have the same configuration as that of the contact portions <NUM>.

As shown in <FIG>, the first driving device <NUM> is configured to drive the pair of first holding members <NUM> to rotate. Specifically, the first driving device <NUM> includes the linear motion mechanism <NUM> and the driving mechanism <NUM> (the second driving device <NUM> has the same configuration as that of the first driving device <NUM>, and includes the linear motion mechanism <NUM> and the driving mechanism <NUM>. A description of the second driving mechanism <NUM> will thus be omitted).

For example, as shown in <FIG>, the linear motion mechanism <NUM> is a cylinder mechanism including two cylinder chambers 124A and 124B where fluid can flow into and that are separated by a piston. The upper ends 118B of the pair of first holding members <NUM> are directly coupled to the respective ends of the linear motion mechanism <NUM>.

As shown in <FIG>, the driving mechanism <NUM> is a mechanism that is built in the wave dissipating block grapple-machine <NUM> and drives one linear motion mechanism <NUM>. As shown in <FIG>, the driving mechanism <NUM> includes a first switching channel member <NUM>, a second switching channel member <NUM>, an electric linear motion mechanism <NUM>, and a second electric linear motion mechanism <NUM>. The first switching channel member <NUM> and the second switching channel member <NUM> are both connected to the two cylinder chambers 124A and 124B and each include two on-off valves BV1 and BV2 (BV3 and BV4). The on-off valves BV1 to BV4 are simple structured valve cocks, such as ball valves, and can be fully closed to prevent the fluid in the two cylinder chambers 124A and 124B from decreasing and can fix the operation of the linear motion mechanism <NUM> (in other words, the driving mechanism <NUM> is configured to include the on-off valves BV1 to BV4 that can prevent the fluid in the two cylinder chambers 124A and 124B from decreasing and can fix the operation of the linear motion mechanism <NUM>).

More specifically, as shown in <FIG>, the first switching channel member <NUM> includes two L-shaped pipes TB1 and TB3, the two on-off valves BV1 and BV2, and a T-shaped pipe TB2. In the first switching channel member <NUM>, the L-shaped pipe TB1 is connected to one end of the on-off valve BV1. One end of the T-shaped pipe TB2 having a fluid discharge outlet FO is connected to the other end of the on-off valve BV1. Moreover, one end of the on-off valve BV2 is connected to the other end of the T-shaped pipe TB2. The L-shaped pipe TB3 is connected to the other end of the on-off valve BV2. In other words, as shown in <FIG>, the first switching channel member <NUM> is configured so that the fluid discharge outlet FO for discharging the fluid from the two cylinder chambers 124A and 124B is disposed between the two on-off valves BV1 and BV2.

As shown in <FIG>, the second switching channel member <NUM> includes two L-shaped pipes TB4 and TB6, the two on-off valves BV3 and BV4, and a T-shaped pipe TB5. In the second switching channel member <NUM>, the L-shaped pipe TB4 is connected to one end of the on-off valve BV3. One end of the T-shaped pipe TB5 having a fluid pressure inlet FI is connected to the other end of the on-off valve BV3. Moreover, one end of the on-off valve BV4 is connected to the other end of the T-shaped pipe TB5. The L-shaped pipe TB6 is connected to the other end of the on-off valve BV4. In other words, as shown in <FIG>, the second switching channel member <NUM> is configured so that the fluid pressure inlet FI for feeding the fluid into the two cylinder chambers 124A and 124B from a pump PP is disposed between the two on-off valves BV3 and BV4.

As shown in <FIG>, the first electric linear motion mechanism <NUM> includes a support unit 134A, a motor unit 134B, a connection unit 134C, a fixed unit 134D, a movable unit 134E, and a coupling unit 134F. The support unit 134A has a not-shown through hole, and is disposed on an end of the connection unit 134C. The first electric linear motion mechanism <NUM> is thereby pivotally supported by a rod 128A attached to a U-shaped casing <NUM>. The motor unit 134B is an electric motor, for example. The connection unit 134C accommodates an encoder, for example. The fixed unit 134D accommodates a ball screw. The rotation of the electric motor is read by the encoder, and the rotation is converted into that of the ball screw. The movable unit 134E can be linearly moved by the rotation of the ball screw. The coupling unit 134F is attached to the movable unit 134E, and simultaneously rotates lever members LK1 and LK2. The lever members LK1 and LK2 are coupled to the on-off valves BV2 and BV4, respectively, and can simultaneously open and close the on-off valves BV2 and BV4 by their rotary motion.

The second electric linear motion mechanism <NUM> has the same configuration as that of the first electric linear motion mechanism <NUM>. As shown in <FIG>, the second electric linear motion mechanism <NUM> includes a support unit 136A, a motor unit 136B, a connection unit 136C, a fixed unit 136D, a movable unit (not shown), and a coupling unit 136F. The second electric linear motion mechanism <NUM> is pivotally supported by a rod 128B attached to the U-shaped casing <NUM>. The coupling unit 136F simultaneously rotates lever members LK3 and LK4. The lever members LK3 and LK4 are coupled to the on-off valves BV1 and BV3, respectively, and can simultaneously open and close the on-off valves BV1 and BV3 by their rotary motion.

In other words, the driving mechanism <NUM> can be said to include the following: the first electric linear motion mechanism <NUM> that simultaneously opens and closes one of the two on-off valves BV1 and BV2 in the first switching channel member <NUM>, here being BV2, and one of the two on-off valves BV3 and BV4 in the second switching channel member <NUM>, here being BV4; and the second electric linear motion mechanism <NUM> that simultaneously opens and closes the other on-off valves BV1 and BV3 in the first switching channel member <NUM> and the second switching channel member <NUM>.

As can be seen from <FIG> and <FIG>, the L-shaped pipes TB1 and TB3 communicate with the cylinder chambers 124B and 124A, respectively. The fluid discharge outlet FO of the T-shaped pipe TB2 is connected to a pipe returning to a pump unit PU (the fluid may be oil or water. If the fluid is water and the water may be drained away, the pipe may be unconnected). In the present embodiment, the wave dissipating block grapple-machine <NUM> includes two built-in linear motion mechanisms <NUM> and two built-in driving mechanisms <NUM>. By contrast, the control unit CU for controlling the first electric linear motion mechanism <NUM> and the second electric linear motion mechanism <NUM> is located outside. The pump unit PU is also located outside, and is shared by the first driving device <NUM> and the second driving device <NUM> by branching the flow channels.

Next, a procedure for grabbing and moving a wave dissipating block CB using the wave dissipating block grapple-machine <NUM> according to the present embodiment will be described with reference to <FIG> and <FIG>.

Using the work machine <NUM>, the wave dissipating block grapple-machine <NUM> is lowered from above the wave dissipating block CB (<FIG>, step S2 in <FIG>).

Next, if needed, the orientation of the wave dissipating block grapple-machine <NUM> is changed to adjust the direction of the second holding mechanism <NUM> in advance by adjusting the feed length of the sub wire Sw with respect to that of the main wire Mw on the basis of the direction of one of two leg portions LP (<FIG>, step S4 in <FIG>). The pair of second holding members <NUM> is then somewhat closed so that the leg portion LP can be grabbed when the wave dissipating block grapple-machine <NUM> is lowered.

Next, the wave dissipating block grapple-machine <NUM> is lowered so that the second holding mechanism <NUM> is engaged with the one leg portion LP (step S6 in <FIG>). In this state, instead of being a firmly grabbing state, the distance between the pair of second holding members <NUM> is greater than the diameter of the leg portion LP so that the wave dissipating block grapple-machine <NUM> can rotate about the leg portion LP.

Next, using the work machine <NUM>, the first holding mechanism <NUM> is brought close to and engaged with the other of the two leg portions LP on the basis of the state of engagement of the second holding mechanism <NUM> (step S8 in <FIG>). In other words, the work machine <NUM> is operated to rotate and adjust the wave dissipating block grapple-machine <NUM> about the one leg portion LP so that the pair of first holding members <NUM> of the first holding mechanism <NUM> can grab the other leg portion LP in a plan view. In such a state, the wave dissipating block grapple-machine <NUM> is lowered further to bring the pair of first holding members <NUM> of the first holding mechanism <NUM> closer so that the first holding members <NUM> make contact with the other leg portion LP.

Next, the other leg portion LP is held by the first holding mechanism <NUM> (step S10 in <FIG>). The one leg portion LP is held by the second holding mechanism <NUM> (step S12 in <FIG>). In other words, the first holding mechanism <NUM> and the second holding mechanism <NUM> hold respective different leg portions LP (<FIG>). Note that the first holding mechanism <NUM> and the second holding mechanism <NUM> may hold the leg portions LP in a reverse order.

Using the work machine <NUM>, the wave dissipating block grapple-machine <NUM> (<FIG>) is then lifted up, and the feed length of the sub wire Sw is adjusted to remove the tilt of the wave dissipating block grapple-machine <NUM>. The wave dissipating block CB is then moved in a stable state that the two leg portions LP other than the held two were directed downward (step S14 in <FIG>).

Next, a procedure for placing a wave dissipating block CB at a predetermined position using the wave dissipating block grapple-machine <NUM> will be described with reference to <FIG>.

Initially, using the work machine <NUM>, the wave dissipating block grapple-machine <NUM> grabbing the wave dissipating block CB is moved to a position above a predetermined position.

Next, using the work machine <NUM>, the wave dissipating block CB is lowered to the predetermined position (<FIG>, step S20 in <FIG>). Here, the wave dissipating block grapple-machine <NUM> is tilted to adjust the orientation of the wave dissipating block CB in advance on the basis of the state of the predetermined position (step S22 in <FIG>). The orientation is adjusted by adjusting the feed length of the sub wire Sw with respect to that of the main wire Mw as described above. After the orientation adjustment, the wave dissipating block CB is placed (<FIG>, step S24 in <FIG>).

Next, the first holding mechanism <NUM> releases the one leg portion LP, and the second holding mechanism <NUM> releases the other leg portion LP (step S26 in <FIG>).

Using the work machine <NUM>, the wave dissipating block grapple-machine <NUM> is then lifted up so that the wave dissipating block grapple-machine <NUM> is separated from the wave dissipating block CB (step S28 in <FIG>).

From when the two leg portions LP are released to when the wave dissipating block grapple-machine <NUM> is lifted up to an appropriate height, the orientation of the wave dissipating block grapple-machine <NUM> is maintained to follow that of the wave dissipating block CB (<FIG>). The feed length of the sub wire Sw is then adjusted to remove the tilt of the wave dissipating block grapple-machine <NUM> (<FIG>).

As described above, in the present embodiment, the first holding mechanism <NUM> and the second holding mechanism <NUM> that radially hold respective two of the four leg portions LP of a wave dissipating block CB having the four leg portions LP extending in respective different directions are provided. The wave dissipating block CB can thus be grabbed more reliably since the number of wave dissipating blocks CB in an orientation where two leg portions LP can be grabbed is considered to be greater than that of wave dissipating blocks CB in an orientation where the vicinity of the barycentric portion can be grabbed as described in the conventional art. The wave dissipating block CB grabbed can be hung in a well-balanced state and can be stably transported since two leg portions LP are directed downward. Moreover, the first holding mechanism <NUM> and the second holding mechanism <NUM> can be configured to only radially hold respective two leg portions LP, and a holding mechanism as large as to embrace an entire leg portion LP is therefore not needed.

For example, according to the conventional art, a grapple-machine for a wave dissipating block of approximately <NUM> tons in weight and approximately <NUM> in height has a weight of approximately <NUM> tons and a height of approximately <NUM>. By contrast, the wave dissipating block grapple-machine <NUM> according to the present embodiment can be configured to be at most less than <NUM> tons in weight and less than <NUM> in height.

In the present embodiment, the first holding mechanism <NUM> and the second holding mechanism <NUM> are configured to be the same as each other, and the first holding mechanism <NUM> and the second holding mechanism <NUM> are configured to be controlled independently of each other. This can promote cost reduction by making common members for the first holding mechanism <NUM> and the second holding mechanism <NUM>. Since the first holding mechanism <NUM> and the second holding mechanism <NUM> are controlled independent of each other, two leg portions LP can be held and released at an optimum timing. This can facilitate the installation and orientation adjustment of wave dissipating blocks CB.

Moreover, in the present embodiment, the cross section of the part of the leg portion LP held by the first holding mechanism <NUM> and the cross section of the part of the leg portion LP held by the second holding mechanism <NUM> are both flat planes. The reaction force to the force applied to the leg portion LP by the first holding mechanism <NUM> thus acts only on the first holding mechanism <NUM>. The reaction force to the force applied to the leg portion LP by the second holding mechanism <NUM> acts only on the second holding mechanism <NUM>. In other words, the holding force of the first holding mechanism <NUM> on the leg portion LP does not depend on the second holding mechanism <NUM>. The holding force of the second holding mechanism <NUM> on the leg portion LP does not depend on the first holding mechanism <NUM>. The leg portions LP can thus be stably held despite the independent driving of the first holding mechanism <NUM> and the second holding mechanism <NUM>.

In the present embodiment, the wave dissipating block CB is held by the pair of first holding members <NUM> and the pair of second holding members <NUM>. Since the wave dissipating block CB is held by four members, stress acting on the wave dissipating block CB can be made smaller than that in the conventional art (where a wave dissipating block is held by three members). This can further reduce breakage of wave dissipating blocks CB.

In the present embodiment, the cross section of the part of the leg portion LP held by the first holding mechanism <NUM> and the cross section of the part of the leg portion LP held by the second holding mechanism <NUM> intersect at an acute angle (approximately <NUM>°). As a result, the first holding mechanism <NUM> and the second holding mechanism <NUM> face the respective leg portions LP (intersecting at approximately <NUM>°) of the wave dissipating block CB used in the present embodiment substantially at right angles. The members of the first holding mechanism <NUM> and the second holding mechanism <NUM> (i.e., the first holding members <NUM> and the second holding members <NUM>) can thus be minimized in size and weight, and the leg portions LP can be held reliably and stably.

The cross section of the part of the leg portion LP held by the first holding mechanism and the cross section of the part of the leg portion LP held by the second holding mechanism are not limited thereto, and may be other than flat planes. The first holding mechanism and the second holding mechanism can be any holding mechanisms that can hold different leg portions LP independently. The cross section of the part of the leg portion LP held by the first holding mechanism and the cross section of the part of the leg portion LP held by the second holding mechanism do not need to intersect at approximately <NUM>° either. The angle may be an acute angle greater than <NUM>° and less than <NUM>°. Even in such a case, a wave dissipating block CB too large and too heavy for the size of the wave dissipating block grapple-machine can be prevented from being grabbed. This can preclude the dropping of the wave dissipating block CB, a breakdown of the wave dissipating block grapple-machine, etc. The cross section of the part of the leg portion LP held by the first holding mechanism and the cross section of the part of the leg portion LP held by the second holding mechanism may intersect at <NUM>° or at <NUM>° or more. The reason is that the wave dissipating block CB can be grabbed so long as the first holding unit and the second holding unit can independently hold different leg portions LP as described above.

In the present embodiment, the base member <NUM> is equipped with the changing member (extending portion 112B) for changing the positional relationship between the first holding mechanism <NUM> and the second holding mechanism <NUM> when rotatably supported by the work machine <NUM>. The orientation of the wave dissipating block grapple-machine <NUM> can thus be changed by changing the feed length of the sub wire Sw with respect to that of the main wire Mw. As a result, the wave dissipating block CB can be grabbed and hung by changing the orientation of the wave dissipating block grapple-machine <NUM> on the basis of the orientation of the wave dissipating block CB. Moreover, in placing the wave dissipating block CB at a predetermined position, the orientation of the wave dissipating block CB can be changed to a desired one before the wave dissipating block CB is placed. However, this method is not restrictive. A wave dissipating block CB may be moved using another work machine so that two leg portions LP can be easily grabbed, before the wave dissipating block CB is grabbed and transported. In transporting and placing a wave dissipating block CB at a predetermined position, the wave dissipating block CB may be once placed near the predetermined position and the orientation thereof can then be changed to a desired one using another work machine.

In the present embodiment, the first driving device <NUM> (second driving device <NUM>) includes one linear motion mechanism <NUM> that is built in the wave dissipating block grapple-machine <NUM> and has respective ends of which the upper ends 118B (upper ends 142B) of the pair of first holding members <NUM> (pair of second holding members <NUM>) are directly coupled. This can simplify the configuration of the first driving device <NUM> (second driving device <NUM>). Suppose now that, in the process of bringing the pair of first holding members <NUM> (pair of second holding members <NUM>) close to each other to hold a leg portion LP, either one of the pair of first holding members <NUM> (pair of second holding members <NUM>) comes into contact with the leg portion LP. In such a case, the leg portion LP can be prevented from undergoing additional pressing force from the first holding member <NUM> (second holding member <NUM>) being in contact therewith first until the first holding member <NUM> (second holding member <NUM>) out of contact rotates alone to make contact with the leg portion LP. This can prevent the application of excessive stress to the leg portion LP, and can further reduce breakage of wave dissipating blocks CB. However, this is not restrictive. Two linear motion mechanisms may be used to rotate the respective first holding members (respective second holding members) independently. A single linear motion mechanism may be used to rotate the pair of first holding members (pair of second holding members) by the same angles.

In the present embodiment, the linear motion mechanism <NUM> is a cylinder mechanism including the two cylinder chambers 124A and 124B where fluid can flow in, which are separated by the piston. As compared to a case where the linear motion mechanism is configured as an electric linear motion mechanism, the pair of first holding members <NUM> (pair of second holding members <NUM>) can therefore be rotated by a linear motion mechanism of small size and at low cost. However, this is not restrictive, and the linear motion mechanism may be configured as an electric linear motion mechanism.

In the present embodiment, the first driving device <NUM> and the second driving device <NUM> each further include a driving mechanism <NUM> that is built in the wave dissipating block grapple-machine <NUM> and drives a linear motion mechanism <NUM>. The driving mechanism <NUM> includes the on-off valves BV1 to BV4 that can prevent the fluid in the two cylinders 124A and 124B from decreasing and fix the operation of the linear motion mechanism <NUM>. Such a configuration can lock the position of the linear motion mechanism <NUM> (i.e., fix the states of the first holding member <NUM> and the second holding member <NUM>) even if the piping extending from the pump unit PU located outside the wave dissipating block grapple-machine <NUM> to the driving mechanism <NUM> is disconnected and the fluid flows out. In other words, even in such a case, unforeseen accidents like dropping of the wave dissipating block CB from the wave dissipating block grapple-machine <NUM> and a change in the orientation of the wave dissipating block CB can be avoided. However, this is not restrictive, and the fluid pressure in the cylinder chambers may be stabilized directly from outside the wave dissipating block grapple-machine without a built-in driving mechanism.

In the present embodiment, the driving mechanism <NUM> includes the first switching channel member <NUM>, the second switching channel member <NUM>, the first electric linear motion mechanism <NUM>, and the second electric linear motion mechanism <NUM>. Here, the first switching channel member <NUM> and the second switching channel member <NUM> are configured to be the same as each other. The first electric linear motion mechanism <NUM> and the second electric linear motion mechanism <NUM> simultaneously open and close the on-off valves BV1 to BV4 of the first switching channel member <NUM> and the second switching channel member <NUM>. The driving mechanism <NUM> can thus be simplified in configuration and control and can reduce cost.

<FIG> shows a driving mechanism DM for comparative purposes. This driving mechanism DM includes two pilot-controlled check valves PV1 and PV2, and a solenoid valve SV. A linear motion mechanism SU shown in <FIG> includes two cylinder chambers SU1 and SU2. The two pilot-controlled check valves PV1 and PV2 are check valves that are coupled to the cylinder chambers SU1 and SU2, and prevent the fluid from flowing out, starting at a time when the amounts of fluid in the respective cylinder chambers are set. The two pilot-controlled check valves PV1 and PV2 are check valves that, if the fluid pressure (pilot pressure) in one cylinder chamber SU1 (or SU2) increases, let the fluid flow out of the other cylinder chamber SU2 (or SU1). The two pilot-controlled check valves PV1 and PV2 are both connected to the solenoid valve SV. The solenoid valve SV is a four-way valve, for example, and switches the pressure feed direction and discharge direction of the fluid using electromagnetic force. A pump unit PU is connected to the solenoid valve SV, and is intended to pressure feed the fluid to the cylinder chambers SU1 and SU2. A control unit CU is intended to control the solenoid valve SV. All the components are installed outside (on the ground).

As described above, the driving mechanism DM includes the two pilot-controlled check valves PV1 and PV2 and the solenoid valve SV, which are complicated in configuration and expensive. The combination of the four simple general-purpose on-off valves (valve cocks such as ball valves) BV1 to BV4, the first electric linear motion mechanism <NUM>, and the second electric linear motion mechanism <NUM> as in the present embodiment can make the control simpler and cost lower than with the driving mechanism DM. Note that the driving mechanism DM can use sequence valves and the like, which again are more expensive than the simple general-purpose on-off valves BV1 to BV4 used in the present embodiment.

The driving mechanism DM is also configured to be able to lock the position of the linear motion mechanism SU even if the cables or piping extending to outside the driving mechanism DM are disconnected. If the driving mechanism DM is used instead of the driving mechanism <NUM>, unforeseen accidents like dropping of the wave dissipating block CB from the wave dissipating block grapple-machine <NUM> and a change in the orientation of the wave dissipating block CB can thus be avoided as well.

In the present embodiment, the fluid is oil or water. If the fluid is oil, the pump unit PU of the work machine <NUM> can be used. However, it is preferable to provide another work machine and use its pump unit PU since the operation of the work machine <NUM> will not be affected by the operation of the wave dissipating block grapple-machine <NUM> (basically, pump units generating hydraulic pressure are less common). If the fluid is water, a water-suction pump unit PU can be used. Here, the greater the size of the pump unit PU is, the higher the discharge performance is and the more quickly the first holding mechanism <NUM> and the second holding mechanism <NUM> can be operated. However, a small-sized general-purpose pump unit may be used. The reason is that the object to be grabbed is a heavy wave dissipating block CB, and for the sake of careful operation, the operation speed of the first holding mechanism <NUM> and the second holding mechanism <NUM> may preferably be not so high. An engine-driven pump unit PU does not need an additional power supply and is less limited in use location. If the fluid is water, such a pump unit PU can be readily prepared. Moreover, the procurement, leakage, and discharge of water are less likely to matter since wave dissipating blocks CB are used in watery places. Note that the fluid is not limited thereto, and air and the like may be used as the fluid.

Consequently, according to the present embodiment, a small-sized lightweight wave dissipating block grapple-machine <NUM> and a wave dissipating block moving method capable of grabbing and moving a wave dissipating block CB safely and more reliably without a dangerous manual slinging operation can be provided. In other words, the wave dissipating block grapple-machine <NUM> can be manufactured at lower cost than that in the conventional art, and can be transported, installed, and used easily. For example, the wave dissipating block grapple-machine <NUM> can quickly and reliably move wave dissipating blocks CB during emergency operations in fear of collapsing river banks and the like.

While the present invention has been described in conjunction with the first embodiment, the present invention is not limited to the first embodiment. It will be understood that improvements and design changes can be made without departing from the gist of the present invention.

For example, in the first embodiment, the orientation of the wave dissipating block grapple-machine <NUM> is changed by adjusting the feed length of the sub wire Sw. However, the present invention is not limited thereto. For example, <FIG> show a second embodiment. The second embodiment is configured so that the sub wire Sw is not needed. The second embodiment will now be described. Differences from the first embodiment are in the configuration and operation of a work machine <NUM> and an attachment unit <NUM>. The other components are therefore denoted by reference numerals with the same last two digits, and a description thereof will basically be omitted.

In the present embodiment, the work machine <NUM> is a backhoe with a foldable arm body <NUM> (having a configuration such as shown in <FIG> of a third embodiment to be described below), for example. As shown in <FIG>, a U-shaped rotation support unit 202A is rotatably supported at the end of the arm body <NUM>. A hook FK is also rotatably supported by the rotation support unit 202A. The hook FK is configured to directly support the attachment unit <NUM>.

A wave dissipating block grapple-machine <NUM> has a similar configuration to that in the first embodiment. As shown in <FIG>, the wave dissipating block grapple-machine <NUM> includes the attachment unit <NUM>, a base member <NUM>, a first holding mechanism <NUM>, and a second holding mechanism <NUM> (driving mechanisms are omitted in <FIG>). The attachment unit <NUM> includes a rotation support portion 212A, an orientation changing unit 212B, and a rotating portion 212C. The rotation support portion 212A is a plate-like member having a main attachment hole 212AA in its upper end, and rotatably supports the rotating portion 212C. The hook FK is engaged with the main attachment hole 212AA. The orientation changing unit 212B includes two coupling units 212BA and 212BC and a cylinder unit 212BB. The coupling unit 212BA is attached to an outer part of the base member <NUM>, and the coupling unit 212BC is rotatably coupled to the rotation support portion 212A. The cylinder unit 212BB is rotatably supported by the two coupling units 212BA and 212BC. As a result, the extension and contraction of the cylinder unit 212BB changes the coupling angle of the rotation support portion 212A to the rotating portion 212C (in other words, even in the present embodiment, the base member <NUM> is equipped with a changing member (orientation changing unit 212B) for changing the positional relationship between the first holding mechanism <NUM> and the second holding mechanism <NUM> when rotatably supported by the work machine <NUM>). The cylinder unit 212BB is driven by hydraulic pressure supplied from the work machine <NUM>.

Next, a procedure for grabbing and moving a wave dissipating block CB using the wave dissipating block grapple-machine <NUM> according to the present embodiment will be described with reference to <FIG>.

Using the work machine <NUM>, the wave dissipating block grapple-machine <NUM> is lowered from above the wave dissipating block CB (<FIG>).

Next, if needed, the orientation of the wave dissipating block grapple-machine <NUM> is changed to adjust the direction of the second holding mechanism <NUM> in advance by adjusting the extension and contraction state of the cylinder unit 212BB on the basis of the direction of one of two leg portions LP (<FIG>). The pair of second holding members is then somewhat closed so that the leg portion LP can be grabbed when the wave dissipating block grapple-machine <NUM> is lowered.

Next, the wave dissipating block grapple-machine <NUM> is lowered so that the second holding mechanism <NUM> is engaged with the one leg portion LP. Using the work machine <NUM>, the first holding mechanism <NUM> is then brought close to and engaged with the other of the two leg portions LP on the basis of the state of engagement of the second holding mechanism <NUM>.

Next, the other leg portion LP is held by the first holding mechanism <NUM>. The one leg portion LP is held by the second holding mechanism <NUM> (<FIG>). Using the work machine <NUM>, the wave dissipating block grapple-machine <NUM> is then lifted up to move the wave dissipating block CB.

In the aforementioned embodiments, the wave dissipating block grapple-machines <NUM> and <NUM> are configured to be hung on the work machines <NUM> and <NUM>. However, the present invention is not limited thereto. For example, <FIG> show a third embodiment. In the third embodiment, the wave dissipating block grapple-machine is attached to the arm body of the work machine so that the orientation of the wave dissipating block grapple-machine can be controlled. Moreover, the configuration of the second holding mechanism is modified. The third embodiment will now be described. Differences from the first and second embodiments are in the junction of a wave dissipating block grapple-machine <NUM> with a work machine <NUM> and the configuration and operation of the wave dissipating block grapple-machine <NUM> except for a first holding mechanism <NUM>. The other components are therefore denoted by reference numerals with the same last two digits, and a description thereof will basically be omitted.

In the present embodiment, as shown in <FIG>, the work machine <NUM> is a backhoe with a foldable arm body <NUM>. The arm body <NUM> is swingably and rotatably supported by a main body unit <NUM>. Like a normal work attachment (such as a cutter and a grapple), the wave dissipating block grapple-machine <NUM> is attached to and supported by a support shaft 302A and a link shaft 302B located at the end of the arm body <NUM>. In other words, the wave dissipating block grapple-machine <NUM> is attached to the arm body <NUM> that can lift up and down the wave dissipating block grapple-machine <NUM> and control rotation and swing of the same.

As shown in <FIG>, the wave dissipating block grapple-machine <NUM> includes an attachment unit <NUM>, a base member <NUM>, the first holding mechanism <NUM>, and a second holding mechanism <NUM>. The first holding mechanism <NUM> and the second holding mechanism <NUM> radially hold respective two of four leg portions LP of a wave dissipating block CB. The base member <NUM> is rotatably supported by the work machine <NUM>, and supports the first holding mechanism <NUM> and the second holding mechanism <NUM>.

Initially, as shown in <FIG>, the attachment unit <NUM> is coupled to the support shaft 302A and the link shaft 302B of the arm body <NUM>. The attachment unit <NUM> is a member that changes the orientation of the wave dissipating block grapple-machine <NUM> on the basis of a change in the position of the link shaft 302B with respect to the support shaft 302A (in other words, even in the present embodiment, the base member <NUM> includes a changing member (attachment unit <NUM>) for changing the positional relationship between the first holding mechanism <NUM> and the second holding mechanism <NUM> when rotatably supported by the work machine <NUM>).

As shown in <FIG>, the base member <NUM> is rotatably supported by the attachment unit <NUM> via a rotation device <NUM>. The rotation device <NUM> allows rotation depending on the balance of the weight of the base member <NUM> acting on the rotation device <NUM>, but may include a driving unit that controls the rotation angle. The base member <NUM> includes a frame 314A, a rotation support portion 314B, a pressure portion 314C, and a second holding mechanism support portion 314D. The frame 314A is rotatably supported by the attachment unit <NUM> as a part of the rotation device <NUM>, and configured to surround a linear motion mechanism <NUM> of the first holding mechanism <NUM> (the driving mechanism is omitted in <FIG>). The rotation support portion 314B is integrated with the frame 314A, and supports a pair of first holding members <NUM> rotatably on a plane parallel to the frame 314A. The cross section of the part of the leg portion LP held by the first holding mechanism <NUM> is thereby configured to be a flat plane. The rotation support portion 314B rotatably supports the pair of first holding members <NUM> by sandwiching and pivotally supporting the pair of first holding members <NUM> with the pressure portion 314C located on the outer side. The second holding mechanism support portion 314D is a member for attaching the second holding mechanism <NUM> to the frame 314A so that the angle between the second holding mechanism <NUM> and the pair of first holding members <NUM> is an acute angle (angle α is approximately <NUM>°).

As shown in <FIG>, the first holding mechanism <NUM> includes the pair of first holding members <NUM> and a first driving device <NUM>. Since the first holding mechanism <NUM> has the same configuration as that in the first embodiment, a description thereof will be omitted.

The second holding mechanism <NUM> includes a ring member <NUM> having an adjustable inner diameter greater than or equal to a minimum outer diameter of a leg portion LP. For example, the ring member <NUM> is an annularly curved wire rope having a thickness of <NUM> or more (depending on the weight of the wave dissipating block CB). The ring member <NUM> is fixed onto the second holding mechanism support portion 314D by adjustment members (such as two U bolts) <NUM> (leg portions LP of several sizes of wave dissipating blocks CB can thus be held by changing the positions where the wire is supported by the adjustment members <NUM> to change the inner diameter of the ring member <NUM> on the basis of the outer diameter of the leg portion LP of the wave dissipating block CB to be grabbed). The outer periphery of the ring member <NUM> may be covered with a cushioning member such as rubber at least in part. The presence of the cushioning member can prevent the wire from being in direct contact with the leg portion LP, and can further reduce breakage of wave dissipating blocks CB. As shown in <FIG>, the ring member <NUM> of the second holding mechanism <NUM> also is formed on the same plane. In other words, both the cross section of the part of the leg portion LP held by the first holding mechanism <NUM> and the cross section of the part of the leg portion LP held by the second holding mechanism <NUM> are configured to be flat planes and intersect at an acute angle (angle α is about <NUM>°).

Next, if needed, the direction of the second holding mechanism <NUM> is adjusted in advance using the work machine <NUM> on the basis of the direction of one of two leg portions LP (<FIG>). The inner diameter of the ring member <NUM> is adjusted in advance.

Next, the other leg portion LP is held by the first holding mechanism <NUM>. The holding by the first holding mechanism <NUM> prevents the one leg portion LP from slipping out of the ring member <NUM>, and the one leg portion LP is held by the second holding member <NUM> (<FIG>).

Using the work machine <NUM>, the wave dissipating block grapple-machine <NUM> is then lifted up to move the wave dissipating block CB.

Next, a procedure for placing the wave dissipating block CB at a predetermined position using the wave dissipating block grapple-machine <NUM> according to the present embodiment will be described. This procedure can basically be implemented by performing operations in reverse order to that of <FIG> on the basis of the flowchart shown in <FIG>. A placement procedure unique to the present embodiment will be described below with reference to <FIG> and <FIG>.

The wave dissipating block grapple-machine <NUM> is initially rotated in a direction toward the main body unit <NUM> of the work machine <NUM>, whereby the wave dissipating block grapple-machine <NUM> grabbing the wave dissipating block CB is lifted up (<FIG>, step S30 in <FIG>).

Next, the wave dissipating block grapple-machine <NUM> is rotated in a direction away from the main body unit <NUM>, whereby the wave dissipating block CB is lowered and horizontally moved (<FIG>, step S32 in <FIG>).

Next, the first holding mechanism <NUM> that is the farther one of the first and second holding mechanisms <NUM> and <NUM> from the main body unit <NUM> releases one leg portion LP (<FIG>, step S34 in <FIG>).

Using the work machine <NUM>, the rotation of the wave dissipating block grapple-machine <NUM> is then stopped to release the other leg portion LP from the second holding mechanism <NUM> (step S36 in <FIG>). The wave dissipating block CB is thereby projected forward so that the wave dissipating block CB is located at a predetermined position (<FIG>, step S38 in <FIG>).

As described above, in the present embodiment, the second holding mechanism <NUM> includes the ring member <NUM> that makes a driving device unnecessary. The wave dissipating block grapple-machine <NUM> can thereby be further reduced in weight (for example, for a wave dissipating block CB of <NUM> tons, the wave dissipating block grapple-machine <NUM> according to the first embodiment has a weight of less than <NUM> tons. The wave dissipating block grapple-machine <NUM> according to the present embodiment can be further reduced to a weight of less than <NUM> tons, i.e., by approximately <NUM> ton). Consequently, in the present embodiment, if the work machine <NUM> is a <NUM>-ton-class backhoe, the wave dissipating block grapple-machine <NUM> according to the present embodiment can be attached to freely move and place wave dissipating blocks CB of less than <NUM> tons that are mainly used on rivers. This enables precise and quick placement of wave dissipating blocks CB that have been unable to be adequately placed at intended predetermined positions using a crane truck or a crane barge. Moreover, the use of the wave dissipating block grapple-machine <NUM> according to the present embodiment enables the projection of wave dissipating blocks CB. At the time of torrential rain or the like with the rising risk of collapsing river banks, wave dissipating blocks CB can thus be quickly moved and piled up from right near the spot as emergency measures.

In the aforementioned embodiments, the wave dissipating block CB has four leg portions LP (with circular radial cross sections) extending from the barycenter of a regular tetrahedron. However, this is not restrictive. For example, a wave dissipating block CB can have any configuration including a plurality of (two or more) leg portions LP extending in respective different directions. The radial cross-sectional shapes of the leg portions LP are not limited to a circular shape, either, and may be elliptic shapes, polygonal shapes, or a combination of these.

Claim 1:
A wave dissipating block grapple-machine (<NUM>,<NUM>,<NUM>) that is supported by a work machine (<NUM>,<NUM>,<NUM>) and can grab a wave dissipating block (CB) having a plurality of leg portions (LP) extending in respective different directions, the wave dissipating block grapple-machine comprising:
a first holding mechanism (<NUM>,<NUM>,<NUM>) and a second holding mechanism (<NUM>,<NUM>,<NUM>) configured to radially hold respective two of the leg portions(LP); and a base member (<NUM>,<NUM>,<NUM>) that is rotatably supported by the work machine (<NUM>,<NUM>,<NUM>), the base member (<NUM>,<NUM>,<NUM>) being configured to support the first holding mechanism (<NUM>,<NUM>,<NUM>) and the second holding mechanism (<NUM>,<NUM>,<NUM>), wherein the first holding mechanism (<NUM>,<NUM>,<NUM>) includes a pair of first holding members (<NUM>,<NUM>,<NUM>) that are rotatably supported by the base member (<NUM>,<NUM>,<NUM>) and can grab one of the two leg portions (LP) by bringing their end portions (118A,218A,318A) close to each other, and a first driving device (<NUM>,<NUM>,<NUM>) configured to drive the pair of first holding members (<NUM>,<NUM>,<NUM>) to rotate,
characterized in that
the second holding mechanism (<NUM>) includes a ring member (<NUM>) having an adjustable inner diameter greater than or equal to a minimum outer diameter of the leg portion (LP).