Abstract:
To set time difference to the starting time of excavation and scooping by setting the starting of the scooping with a bucket behind the starting of the excavation with a ripper in an excavation machine where the bucket and the ripper are equipped to an arm, and are manipulated to open and close with each other by expansion and contraction of a hydraulic cylinder During the first half of the contracting process at a hydraulic cylinder, a pin mounted on a connecting link where a bucket and a ripper are connected moves through a slot formed on the bucket to make bucket delay in closing, and the bucket and the ripper close at the same time during the latter half of the contracting process.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a national phase application of International Patent Application No. PCT/EP2015/080204 filed Dec. 17, 2015, which claims priority to Japanese Patent Application No. 2014-256339 filed Dec. 18, 2014, both of which are incorporated by reference herein in their entireties for all purposes. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to the technical field of a front attachment in a traveling machine body for operation such as a hydraulic shovel. 
       BACKGROUND ART 
       [0003]    Generally, in a known traveling machine body for operation such as a hydraulic shovel, a first operating body such as a bucket and a second operating body such as a ripper are provided as a front attachment to be openable and closable, such that a dug object dug with the second operating body is scooped with the first operating body and wood and the like is held (sandwiched) with the two operating bodies (e.g., see PTL 1 and 2). 
       CITATION LIST 
     Patent Literature 
       [0004]    [PTL 1] 
         [0005]    Japanese Utility Model Application Laid-open No. H2-136148 
         [0006]    [PTL 2] 
         [0007]    Japanese Patent No. 4936784 
       SUMMARY OF INVENTION 
     Technical Problem 
       [0008]    However, since the configuration in PTL 1 is such that a dedicated hydraulic cylinder is provided to each of the respective operation arms to open or close the two operating bodies, there is a problem in that the number of parts becomes large and that tremendous burden is placed particularly on an inexperienced operator due to a troublesome manipulation being required for a complicated mechanism for separately operating the two hydraulic cylinders. 
         [0009]    In contrast, in PTL 2, an opening or closing operation of the two operating bodies is performed with one hydraulic cylinder, thereby overcoming the drawback of PTL 1 described above such as the number of parts becoming large or the burden on an operator being large. However, the opening or closing operation of the two operating bodies are simultaneous in the case of an extending or contracting operation of the hydraulic cylinder herein, and therefore, despite there being not much trouble in the case of a simple holding operation, there is a problem of a disadvantage in operation performance due to a scooping operation being too early in the case where two operations are involved such as the first operating body scooping an object dug with the second operating body; here lies the problem to be solved by the present invention. 
       Solution to Problem 
       [0010]    The present invention has been created for the purpose of solving these problems in view of the circumstances as described above. An invention of claim  1  is a front attachment in a traveling machine body for operation, including: a first operating body provided to be swingable at a tip end section of an arm; a second operating body provided to be swingable at an intermediate section of the arm; a hydraulic cylinder of which a base end section is provided to the arm and a tip end section is provided to a base end section of the second operating body; and a connecting link that connects the first operating body and the second operating body, the first operating body and the second operating body being configured to perform an opening or closing operation along with an extending or contracting operation of the hydraulic cylinder, wherein operation delaying means for delaying a closing operation of the first operating body by causing the second operating body to perform a closing operation in advance in a process of contracting the extended hydraulic cylinder is provided to a connecting section for the first operating body and the connecting link. 
         [0011]    An invention of claim  2  is the front attachment in a traveling machine body for operation according to claim  1 , wherein the operation delaying means includes a slot provided to the first operating body and a pin provided to the connecting link to be movable in the slot, and is configured to cause only the second operating body to perform the closing operation in advance by the pin moving in the slot in a first half of the process of contracting the hydraulic cylinder, and cause both of the first operating body and the second operating body to perform the closing operation in a second half of the process of contracting the hydraulic cylinder after the pin has moved to a moving end of the slot, thus delaying the closing operation of the first operating body with respect to the closing operation of the second operating body. 
         [0012]    An invention of claim  3  is the front attachment in a traveling machine body for operation according to claim  1  or  2 , wherein the first operating body is a bucket, and the second operating body is a ripper. 
       Advantageous Effects of Invention 
       [0013]    With the invention of claim  1 , the second operating body first performs the closing operation alone, and then the first and second operating bodies perform the closing operation together, in the process of contracting the one hydraulic cylinder. As a result, smoothly performing an operation with a time lag such as the first operating body scooping an object dug with the second operating body can be easy even for an inexperienced operator. With the invention of claim  2 , the operation delaying means for delaying the closing operation of the first operating body by causing the second operating body to perform the closing operation in advance can be configured easily. 
         [0014]    With the invention of claim  3 , an object first dug with the ripper can be scooped with the bucket with a time lag, in the digging of hard soil. Thus, the operation performance is improved, and early wear of the bucket as in the case where the bucket performs all of such digging and scooping operations can be avoided. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0015]      FIG. 1  is an overall side view of a hydraulic shovel. 
           [0016]      FIG. 2  is a side view of a front attachment. 
           [0017]      FIG. 3  is a perspective view of the main section of the front attachment. 
           [0018]      FIG. 4  is a side view showing a state where a hydraulic cylinder has extended maximally when an arm is in a crowding posture. 
           [0019]      FIG. 5  is a side view showing a state where the hydraulic cylinder has contracted and a pin has moved to a moving end of a slot when the arm is in the crowding posture. 
           [0020]      FIG. 6  is a side view showing a state where the hydraulic cylinder has contracted maximally when the arm is in the crowding posture. 
           [0021]      FIG. 7  is a side view showing a state where the hydraulic cylinder has extended maximally when the arm is in a perpendicular posture. 
           [0022]      FIG. 8  is a side view showing a state where the hydraulic cylinder has contracted and the pin has moved to a moving end of the slot when the arm is in the perpendicular posture. 
           [0023]      FIG. 9  is a side view showing a state where the hydraulic cylinder has contracted maximally when the arm is in the perpendicular posture. 
           [0024]      FIG. 10  is a side view showing a state where the hydraulic cylinder has extended maximally when the arm is in a dump posture. 
           [0025]      FIG. 11  is a side view showing a state where the hydraulic cylinder has contracted and the pin has moved to the moving end of the slot when the arm is in the dump posture. 
           [0026]      FIG. 12  is a side view showing a state where the hydraulic cylinder has contracted maximally when the arm is in the dump posture. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0027]    An embodiment for carrying out the present invention will be described below based on the drawings. In the drawings,  1  denotes a traveling machine body of a hydraulic shovel. In the traveling machine body  1 , an upper slewing body  3  is mounted on a crawler-type lower traveling body  2  to be capable of slewing about a vertical axis. In the upper slewing body  3 , the configuration including various member devices such as a front operation section  4 , an operator&#39;s cab (cab)  5 , an engine room  6 , and a counterweight  7 , which are to be described later, is in accordance with the prior art. 
         [0028]    The front operation section  4  is provided with a boom  8  of which the base end section is axially supported to be rotatable at the upper slewing body  3  and that is moved up and down by an extending or contracting operation of a boom cylinder  8   a , an arm (stick)  9  that is axially supported to be rotatable at the tip end section of the boom  8  with a supporting shaft  9   a  and moved dump and crowd by an extending or contracting operation of an arm cylinder  9   b , and a front attachment A with which the present invention is carried out at the tip end section (front end section) of the arm  9 . The front attachment A is configured as follows. First, a bucket (corresponding to “first operating body” of the present invention)  10  axially supported to be rotatable at the tip end section of the arm  9  with a supporting shaft  10   a  is provided, and the intermediate section of a ripper (corresponding to “second operating body” of the present invention)  11  is axially supported to be swingable at the intermediate section of the arm  9  in the length direction with a first supporting shaft  11   a . In the ripper  11 , a claw section  11   b  for breaking a hard ground surface or bedrock is provided on the traveling machine body  1  side (rear side) to oppose an opening section  10   b  of the bucket  10 . The claw section  11   b  may obviously be one-clawed or be in a forked shape that is branched to be, for example, two-clawed, three-clawed, or the like. 
         [0029]    The ripper  11  is provided with a base end section  11   c  that extends to the opposite side (front side) of the bucket opening section  10   b . The base end section  11   c  is axially supported to be swingable with a second supporting shaft  12   c  at the tip end section of a rod  12   b  of a hydraulic cylinder  12  that is axially supported at the base end section of the arm  9  with a first supporting shaft  12   a  and provided such that the rod  12   b  protrudes forward. Further, one end section of a connecting link  13  is axially supported to be swingable with a second supporting shaft  11   d  at the intermediate section on the claw section  11   b  side of the ripper  11 . The other end section (front end section) of the connecting link  13  is provided with a pin  13   a . The pin  13   a  penetrates and is supported to be movable at a slot (corresponding to “operation delaying means” of the present invention)  10   d  provided to a base end section  10   c  protruding to the opposite side (front side) of the main body of the bucket  10 . In this embodiment, the slot  10   d  is formed by being cut into an upwardly inclined shape, for example on a tangent C, to deviate from an arc B of which the shaft center is the bucket supporting shaft  10   a . As a reference, in the case where the slot  10   d  is formed along the arc B, support by a slot upper-side circumferential edge  10   g  by the pin  13   a  as described later is lost. Therefore, the bucket  10  is rotated by its own weight in accordance with the contraction of the hydraulic cylinder, and the present invention is not possible. 
         [0030]    Herein, in a perpendicular posture in which the bucket supporting shaft  10   a  is located on a perpendicular (arm perpendicular) D from the arm supporting shaft  9   a  as shown in  FIG. 7 , a bucket gravity center E is located in the front relative to the arm perpendicular D. In this state, the bucket  10  tries to rotate rearward with its own weight. Accordingly, the bucket  10  is maintained in a posture in which the pin  13   a  contacts an upper end  10   e  of the slot  10   d.    
         [0031]      FIGS. 4 to 6  show the motion of the front attachment A upon causing an extending or contracting movement of the hydraulic cylinder  12 , in the case of the bucket supporting shaft  10   a  being located on the traveling machine body  1  side (rear side) relative to the perpendicular (arm perpendicular) D from the arm supporting shaft  9   a  (an arm crowding posture). When the hydraulic cylinder  12  is in a maximally extended state (see  FIG. 4 ), the setting is such that the bucket gravity center E of the bucket  10  is located on a perpendicular (bucket perpendicular) K from the bucket supporting shaft  10   a  within a range of the slot  10   d . The setting is such that, accordingly, the bucket  10  sinks from a posture (posture of a virtual line in  FIG. 4 ) in which the pin  13   a  contacts the slot upper end  10   e  to be located in an intermediate position of the slot  10   d.    
         [0032]    When the hydraulic cylinder  12  is contracted from this state, the cylinder second supporting shaft  12   c  is located at the intersection of a center line F of the hydraulic cylinder  12  and an arc G of which the center is the first supporting shaft  11   a . In the ripper  11  at this time, the claw section  11   b  swings toward the lower side with the first supporting shaft  11   a  as a fulcrum in a state of coordination with the arc G. Meanwhile, the second supporting shaft  11   d  swings on an arc H with the first supporting shaft  11   a  as a fulcrum. Then, the connecting link  13  moves in coordination with the swing of the second supporting shaft  11   d . The pin  13   a  is brought to a state of being supported at an upper-side circumferential edge  10   g  of the slot  10   d  and moves toward a lower end (front end)  10   f  of the slot  10   d . During the first half of a contracting process until the pin  13   a  contacts the slot lower end  10   f  (see  FIG. 5 ), the pin  13   a  pushes the slot lower end  10   f  forward, so that a scooping operation of the bucket  10  is absent. During this time, the scooping operation of the bucket  10  is delayed, and only the ripper  11  performs a digging operation with a lower-side swing of the claw section  11   b , with the first supporting shaft  11   a  serving as a fulcrum. 
         [0033]    During the second half of the contracting process from this state until the hydraulic cylinder  12  is further contracted and moved to a maximally contracted state (see  FIG. 6 ), the ripper  11  swings downward along the arc H of the second supporting shaft  11   d  to continue the swing operation of the ripper  11 . Simultaneously, the pin  13   a  pushes the slot lower end  10   f  forward and downward up to an intersecting position of an arc I of which the center is the ripper second supporting shaft  11   d  and an arc J of which the center is the bucket supporting shaft  10   a , so that the bucket  10  performs the scooping operation in which the opening section  10   b  moves upward. Accordingly, the posture is such that the ripper claw section  11   b  covers the bucket opening section  10   b.    
         [0034]    Next,  FIGS. 7 to 9  show the motion of the front attachment A upon causing an extending or contracting movement of the hydraulic cylinder  12 , in the case of the bucket supporting shaft  10   a  being located on the perpendicular K from the arm supporting shaft  9   a  (an arm perpendicular posture). (Hereinafter, description relating to the arc or the like is the same and therefore omitted.) In a state where the hydraulic cylinder  12  is maximally extended (see  FIG. 7 ), the bucket  10  is in a posture in which the bucket gravity center E is located in the front relative to the arm perpendicular D. Accordingly, the bucket  10  tries to rotate toward the arm perpendicular D side with its own weight and is in a posture in which the pin  13   a  contacts the slot upper end  10   e.    
         [0035]    In the ripper  11 , when the hydraulic cylinder  12  is contracted from this state, the claw section  11   b  swings toward the lower side with the first supporting shaft  11   a  as a fulcrum, while the second supporting shaft  11   d  swings with the first supporting shaft  11   a  as a fulcrum. The bucket  10  is brought to a state where the pin  13   a  is supported at the upper-side circumferential edge  10   g  of the slot  10   d , and the pin  13   a  moves toward the lower end (front end)  10   f  of the slot  10   d . During the first half of a contracting process until the pin  13   a  contacts the slot lower end  10   f  (see  FIG. 8 ), the pin  13   a  pushes the slot lower end  10   f  forward, so that a scooping operation of the bucket  10  is absent. During this time, the scooping operation of the bucket  10  is delayed, and only the ripper  11  performs a digging operation with a lower-side swing of the claw section  11   b , with the first supporting shaft  11   a  serving as a fulcrum. 
         [0036]    During the second half of the contracting process from this state until the hydraulic cylinder  12  is further contracted and moved to a maximally contracted state (see  FIG. 9 ), the swinging operation of the ripper  11  is continued. Simultaneously, the pin  13   a  pushes the slot lower end  10   f  forward and downward, so that the bucket  10  performs the scooping operation in which the opening section  10   b  moves upward. Accordingly, the posture is such that the ripper claw section  11   b  covers the bucket opening section  10   b.    
         [0037]    Further,  FIGS. 10 to 12  show the motion of the front attachment A upon causing an extending or contracting movement of the hydraulic cylinder  12 , in the case of the bucket supporting shaft  10   a  being located on the front side relative to the arm perpendicular D (an arm dump posture). In a state where the hydraulic cylinder  12  is maximally extended (see  FIG. 10 ), the bucket  10  is in a posture in which the bucket gravity center E is located in the front relative to the arm perpendicular D. Accordingly, the bucket  10  tries to rotate toward the arm perpendicular K side with its own weight and is in a posture in which the pin  13   a  contacts the slot upper end  10   e.    
         [0038]    In the ripper  11 , when the hydraulic cylinder  12  is contracted from this state, the claw section  11   b  swings toward the lower side with the first supporting shaft  11   a  as a fulcrum, while the second supporting shaft  11   d  swings with the first supporting shaft  11   a  as a fulcrum. The bucket  10  is brought to a state where the pin  13   a  is supported at the upper-side circumferential edge  10   g  of the slot  10   d , and the pin  13   a  moves toward the lower end (front end)  10   f  of the slot  10   d . During the first half of a contracting process until the pin  13   a  contacts the slot lower end  10   f  (see  FIG. 11 ), the pin  13   a  pushes the slot lower end  10   f  forward, so that a scooping operation of the bucket  10  is absent. During this time, the scooping operation of the bucket  10  is delayed, and only the ripper  11  performs a digging operation with a lower-side swing of the claw section  11   b , with the first supporting shaft  11   a  serving as a fulcrum. 
         [0039]    During the second half of the contracting process from this state until the hydraulic cylinder  12  is further contracted and moved to a maximally contracted state (see  FIG. 12 ), the swing operation of the ripper  11  is continued. Simultaneously, the pin  13   a  pushes the slot lower end  10   f  forward and downward, so that the bucket  10  performs the scooping operation in which the opening section  10   b  moves upward. Accordingly, the posture is such that the ripper claw section  11   b  covers the bucket opening section  10   b.    
         [0040]    In the case where the extended hydraulic cylinder  12  is contracted in a configuration in which the bucket  10  and the ripper  11  are provided to the arm  9  in the embodiment for carrying out the present invention configured as described above, the pin  13   a  provided to the connecting link  13  that connects the bucket  10  and the ripper  11  moves in the slot  10   d  provided to the bucket  10  from the upper end  10   e  (or midway) to the lower end  10   f  in the first half of a contracting process. In this first half of the contracting process, a delaying posture in which a scooping swing of the bucket  10  is not performed and stopped is maintained, and the claw section  11   b  of the ripper  11  moves downward (moves to the closing side) to perform a digging operation. 
         [0041]    In the second half of the contracting process after the pin  13   a  has reached the lower end  10   f  of the slot  10   d , the downward movement of the ripper  11  on the closing side is continued, and the pin  13   a  contacts the slot lower end  10   f  to press the base end section  10   c  of the bucket  10  to the front side. The bucket  10  performs a scooping operation in which the opening section  10   b  moves upward, and the ripper  11  operates to close the bucket opening section  10   b.    
         [0042]    When the present invention is carried out in this manner, the bucket  10  and the ripper  11  perform an opening or closing operation in coordination with an extending or contracting operation of the one hydraulic cylinder  12 . In the first half of a contracting process of the hydraulic cylinder in this case, only the ripper  11  performs a closing operation, and the bucket  10  maintains a delaying posture to remain stopped. In the second half of the contracting process after the pin  13   a  has reached the front end  10   f  that is a moving end of the slot  10   d , the bucket  10  also performs a closing operation together with the ripper  11 . That is, in the process of contracting the one hydraulic cylinder  12 , the bucket  10  performs the closing operation subsequently in a state where there is a time lag with respect to the ripper  11 , and a dug object dug by a digging operation can be subjected to a scooping operation with the bucket  10  subsequently in a delayed state with a time lag. A sequence of digging and scooping operations can be performed in a state of having a time lag, and the operation performance is improved. 
         [0043]    Since the digging operation by the ripper  12  and the scooping operation by the bucket  10  with a time lag can be performed with an extending or contracting operation of the one hydraulic cylinder  12 , simplification of structure can be achieved, and manipulation can be easy even for an inexperienced operator. 
         [0044]    Moreover, in the case of digging hard soil, soil dug with the ripper  12  is scooped with the bucket  10 . Therefore, wear of the bucket  10  can be reduced compared to a case where both of the digging and scooping operations are performed with the bucket  10  alone. 
         [0045]    Moreover, in a configuration of delaying the closing operation of the bucket  10  with respect to the closing operation of the ripper  11  herein, the pin  13   a  provided to the connecting link  13  that connects the bucket  10  and the ripper  11  can move in the slot  10   d  provided to the bucket  10 . Thus, the configuration of a delaying mechanism is simple. 
         [0046]    The present invention is obviously not limited to the embodiment. The bucket can be replaced with an operating body such as a ripper. The delaying mechanism can be carried out with a slot being provided to a connecting link and a pin being provided to a bucket. 
         [0047]    As a reference, the shape of the slot  10   d  is determined based on the first half of a contracting operation of the hydraulic cylinder  12  from a maximally extended state. By determining the respective positions of the upper end (base end)  10   e  and the lower end (tip end)  10   f  of the slot  10   d  that the pin  13   a  contacts in that case and connecting the positions with a line, the bucket can be set to not swing in the first half of the contracting process. The tangent as in the embodiment is obviously not limiting. 
       INDUSTRIAL APPLICABILITY 
       [0048]    The present invention can be utilized as a front attachment provided to a traveling machine body for operation such as a hydraulic shovel.