Holding and cutting device, and work vehicle equipped with the same

Abstract

To provide a holding and cutting device capable of cutting even thick grappled materials such as standing trees while holding them.SOLUTION: Provided is a holding and cutting device (10) that cuts a grappled material, such as a standing tree or timber, while holding it, the device comprising: a main body (12b); a pair of grapple arms (14, 15) rotatably attached to the main body for holding the grappled material; and a chainsaw unit (16) attached to the main body for cutting the grappled material while being held by the grapple arms, wherein the chainsaw unit comprises: a frame (16a); a chainsaw (18) mounted to the frame; and a chainsaw swing mechanism (24) that swings the chainsaw to cut the grappled material, and the chainsaw is supported on the main body so as to be elastically swingable.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a holding and cutting device, and more particularly to a holding and cutting device that holds and cuts a grappled material, such as a standing tree or wood, and a work vehicle equipped with the same. [Background technology]

[0002] A grapple saw is described in Japanese Utility Model Application Laid-Open Publication No. 2-130303 (Patent Document 1). This grapple saw is provided with a grapple unit that is rotatably attached to the tip of an arm of a construction machine that rotates up and down and that holds wood or the like, and a chain saw device that is attached to one end of the grapple unit and cuts the held wood or the like. In this way, a holding and cutting device that holds and cuts a grappled material such as standing trees or wood is known.

[0003] Such a holding and cutting device is configured to cut the held wood or the like by rotating the saw portion of the chain saw about a predetermined axis while the saw chain device is operating. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Utility Model Application Publication No. 2-130303 Summary of the Invention [Problem to be solved by the invention]

[0005] It is possible to cut relatively thin wood, etc., with a holding and cutting device equipped with a chainsaw as a cutting device, such as the grapple saw device described in Patent Document 1. However, when trying to cut down a particularly thick standing tree, the chainsaw cannot be advanced once a cut of about 1 / 3 to 1 / 2 of the diameter is made with the chainsaw, and if one tries to force the chainsaw to advance, the cut part of the wood heats up and starts smoking, making it impossible to cut the tree.

[0006] Therefore, an object of the present invention is to provide a holding and cutting device that can hold and cut even grappled materials such as thick standing trees, and a work vehicle equipped with the same. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides a holding and cutting device that holds and cuts a grappled material, which is a standing tree or timber, and comprises a main body, a pair of grapple arms that are rotatably attached to the main body and hold the grappled material, and a chainsaw unit attached to the main body for cutting the grappled material held by the grapple arms, the chainsaw unit comprising a frame, a chainsaw attached to the frame, and a chainsaw rotation mechanism that rotates the chainsaw so as to cut the grappled material, and the chainsaw is supported so as to be elastically swingable relative to the main body.

[0008] In the present invention configured as described above, the grappled material is held by a pair of grapple arms rotatably attached to the main body. Meanwhile, a chainsaw unit is attached to the main body, and a chainsaw rotation mechanism of the chainsaw unit rotates the chainsaw to cut the grappled material held by the grapple arms. According to the present invention configured as described above, since the chainsaw is elastically supported by the main body, the chainsaw oscillates slightly when cutting into the grappled material to cut it. This allows the force acting on the guide bar of the chainsaw to be deflected, and the force that hinders the movement of the guide bar during cutting is reduced, so that even when cutting a thick grappled material, the chainsaw can be advanced to the end, and even a thick grappled material can be cut.

[0009] In the present invention, it is preferable to further have a pivotal support mechanism that supports the chainsaw so that it can elastically swing relative to the main body, and this pivotal support mechanism includes a support shaft that supports the chainsaw so that it can pivot relative to the main body, and an elastic member that generates a biasing force so that the chainsaw returns to a predetermined rotation position.

[0010] According to the present invention configured in this manner, the chainsaw is supported by a pivoting support mechanism equipped with a support shaft and an elastic member, so that the rotation direction of the chainsaw is regulated by the support shaft while allowing movement of the chainsaw due to elastic deformation of the elastic member, thereby enabling the chainsaw to produce the desired swing motion.

[0011] In the present invention, the support axis of the pivot support mechanism is preferably oriented parallel to a plane including the guide bar of the chain saw.

[0012] According to the present invention configured in this manner, the support axis of the pivoting support mechanism is oriented parallel to a plane including the guide bar of the chainsaw, so that a swing motion occurs in the guide bar that subtly changes its cutting angle, making it easy to reduce the resistance acting on the guide bar.

[0013] In the present invention, the chain saw unit is preferably attached to the main body via a pivot support mechanism.

[0014] According to the present invention configured in this manner, the chainsaw unit is attached to the main body via a pivoting support mechanism, so that the chainsaw can be elastically swung relative to the main body while using the existing chainsaw unit as is.

[0015] In the present invention, preferably, the tool further includes a translational support mechanism that supports the chainsaw so that it can elastically swing relative to the main body, and this translational support mechanism allows translational movement of the chainsaw relative to the main body and is equipped with an elastic member that generates a biasing force so that the chainsaw returns to a predetermined translational position.

[0016] According to the present invention configured as described above, since the chain saw is supported by the translation support mechanism, it is possible to generate a swing motion in the chain saw with a simple mechanism.

[0017] The present invention also relates to a work vehicle capable of felling or cutting standing trees or timber, characterized in that it has a runnable carriage and the holding and cutting device of the present invention attached to the carriage. Effect of the Invention

[0018] According to the holding and cutting device of the present invention and the work vehicle equipped with the same, even grappled materials such as thick standing trees can be held and cut. [Brief description of the drawings]

[0019] [Figure 1] 1 is a diagram showing an entire working vehicle equipped with a holding and cutting device according to a first embodiment of the present invention. [Diagram 2] 1 is a front view of a holding and cutting device according to a first embodiment of the present invention. [Diagram 3] 1 is a front view showing a holding and cutting device according to a first embodiment of the present invention with a chainsaw unit removed; [Figure 4] 1 is a side view of a holding and cutting device according to a first embodiment of the present invention. FIG. [Diagram 5] 1 is a perspective view showing a part of a chain saw unit provided in a holding and cutting device according to a first embodiment of the present invention. FIG. [Figure 6] 3 is an enlarged view of a unit support mechanism that supports a chainsaw unit provided in the holding and cutting device according to the first embodiment of the present invention. FIG. [Figure 7] 5A to 5C are diagrams illustrating the operation of the holding and cutting device according to the first embodiment of the present invention. [Figure 8] FIG. 11 is a side view showing a support structure for a chain saw provided in a holding and cutting device according to a second embodiment of the present invention. [Figure 9]13 is a side view showing a support structure for a chain saw according to a modified embodiment of the present invention. FIG. [Figure 10] 1 is a diagram showing an example in which a holding and cutting device according to an embodiment of the present invention is applied to a felling work vehicle. [Figure 11] 1 is a diagram showing an example in which a holding and cutting device according to an embodiment of the present invention is applied to a felling work vehicle. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Next, a work vehicle according to an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a diagram showing an entire working vehicle equipped with a holding and cutting device according to a first embodiment of the present invention. FIG. 2 is a front view of the holding and cutting device according to the first embodiment of the present invention. FIG. 3 is a front view showing the holding and cutting device according to the first embodiment of the present invention with the chainsaw unit removed. FIG. 4 is a side view of the holding and cutting device according to the first embodiment of the present invention. FIG. 5 is a perspective view showing a part of the chainsaw unit provided in the holding and cutting device according to the first embodiment of the present invention. FIG. 6 is an enlarged view of a unit support mechanism that supports the chainsaw unit provided in the holding and cutting device according to the first embodiment of the present invention. FIG. 7 is a diagram showing the operation of the holding and cutting device according to the first embodiment of the present invention.

[0021] As shown in Fig. 1, a work vehicle 1 according to an embodiment of the present invention has a vehicle body 2, a traveling section 4, a first work arm 6 rotatably attached to the vehicle body 2, and a second work arm 8 rotatably attached to the tip of the first work arm 6. Furthermore, the work vehicle 1 has a holding and cutting device 10 according to the first embodiment of the present invention attached to the tip of the second work arm 8.

[0022] The vehicle body 2 is the main body of the work vehicle 1, and is configured to be capable of traveling by a running section 4 provided on the underside. In addition, a driver's seat 2a in which an operator sits is provided on one side at the front of the vehicle body 2. The running part 4 is a cart that is provided with crawlers 4a on both sides and is capable of running. The car body part 2 is attached to the upper side of the running part 4, and this car body part 2 is attached to the running part 4 so as to be rotatable around an axis line vertical to the running part 4.

[0023] The first working arm 6 is an arm bent in an "L" shape and attached to the center of the front of the vehicle body 2. The base end of the first working arm 6 is attached to the vehicle body 2 so as to be rotatable about a horizontal axis. Furthermore, two hydraulic cylinders 6a are attached to connect the front of the vehicle body 2 and the middle part of the first working arm 6, and the first working arm 6 can be rotated up and down relative to the vehicle body 2 by extending and retracting these hydraulic cylinders 6a.

[0024] The second working arm 8 is a straight arm rotatably attached to the tip of the first working arm 6. The base end of the second working arm 8 is rotatably attached to the tip of the first working arm 6 about a horizontal axis. Furthermore, a hydraulic cylinder 8a is attached to connect the intermediate portion of the first working arm 6 and the base end of the second working arm 8, and the second working arm 8 can be rotated up and down relative to the first working arm 6 by extending and retracting this hydraulic cylinder 8a.

[0025] The holding and cutting device 10 according to the first embodiment of the present invention is attached to the tip of the second working arm 8, and is configured to hold and cut a grappled material such as a standing tree or lumber. The main body of the holding and cutting device 10 is attached to the tip of the second working arm 8 so as to be rotatable about a horizontal axis. In addition, a hydraulic cylinder 10a is attached to connect the base end of the second working arm 8 and the main body of the holding and cutting device 10, and the holding and cutting device 10 can be rotated relative to the second working arm 8 by extending and retracting this hydraulic cylinder 10a.

[0026] The work vehicle 1 of this embodiment, having the above configuration, can move to a desired location and cut a standing tree to be felled while holding it with the holding and cutting device 10. Alternatively, the work vehicle 1 can cut a piece of wood placed on the ground while holding it with the holding and cutting device 10.

[0027] As shown in Figures 2 to 4, the holding and cutting device 10 according to the first embodiment of the present invention has a first body portion 12a and a second body portion 12b, a pair of grapple arms 14, 15 rotatably attached to the second body portion 12b, and a chainsaw unit 16 attached to one side of the second body portion 12b. The holding and cutting device 10 of this embodiment is configured to hold a grappled material such as a standing tree or wood between the grapple arms 14, 15 and the second body portion 12b by rotating the grapple arms 14 and 15 in a direction in which they approach each other. Then, in a state in which the grappled material is held, the chainsaw 18 is extended from the chainsaw unit 16 to cut the grappled material.

[0028] As shown in FIG. 2, in this embodiment, the main body portion is made up of a first main body portion 12a and a second main body portion 12b rotatably attached to the first main body portion 12a. Two fulcrums are provided on first main body portion 12a, and the tip of second working arm 8 is rotatably connected to one of the fulcrums, and the tip of a "L"-shaped link member 8b connected to second working arm 8 is rotatably connected to the other fulcrum. In addition, the tip of hydraulic cylinder 10a is rotatably connected to the bent middle portion of link member 8b. As a result, by extending and retracting hydraulic cylinder 10a, first main body portion 12a is rotated around the fulcrum at the tip of second working arm 8, via link member 8b.

[0029] In addition, a hydraulic motor (not shown) is built into the first body portion 12a, which allows the second body portion 12b to rotate relative to the first body portion 12a about an axis extending in the vertical direction in Fig. 2. Therefore, the holding and cutting device 10 can orient the grapple arms 14, 15 in any direction, and can grip standing trees that are standing vertically or lumber lying on the ground.

[0030] The second body portion 12b is rotatably attached to the first body portion 12a. The base ends of a pair of grapple arms 14, 15 are rotatably attached to the second body portion 12b. The grapple arms 14, 15 are rotated so that the tips of the grapple arms 14, 15 approach the second body portion 12b, thereby holding the grappled material.

[0031] As shown in FIG. 3 and FIG. 4, the grapple arm 14 is composed of two curved plate portions 14a curved in a crescent shape and arranged in parallel, and a connecting plate portion 14b connecting the tip portions of these curved plate portions 14a. The base end portion of each curved plate portion 14a is rotatably attached to one end of the second main body portion 12b, and the connecting plate portion 14b extends in a direction perpendicular to the curved plate portion 14a and connects the tip portions of the two curved plate portions 14a. Similarly, the grapple arm 15 is composed of two curved plate portions 15a curved in a crescent shape and arranged in parallel, and a connecting plate portion 15b connecting the tip portions of these curved plate portions 15a. In addition, the base end portion of each curved plate portion 15a is rotatably attached to the other end of the second main body portion 12b.

[0032] As shown in FIG. 4, each curved plate portion 14a is located outside each curved plate portion 15a, and when the grapple arm 14 and the grapple arm 15 are closed, the grapple arm 15 is inserted inside the grapple arm 14. As shown in FIG. 3, the base end of the grapple arm 14 is attached to one end of the second main body portion 12b so as to be rotatable around a rotation shaft 20a. Similarly, the base end of the grapple arm 15 is attached to the other end of the second main body portion 12b so as to be rotatable around a rotation shaft 22a. The grapple arms 14 and 15 can be opened and closed by extending and retracting a hydraulic cylinder 22 connected to the grapple arms 14 and 15 via a link member (not shown).

[0033] Next, as shown in Figures 2 and 4, the chainsaw unit 16 is attached to one side of the second main body portion 12b. The chainsaw unit 16 has a frame 16a, a chainsaw 18 stored in the frame 16a, and a chainsaw rotation mechanism 24 (Figure 5) that rotates the chainsaw 18. As described below, the chainsaw rotation mechanism 24 is configured to rotate a guide bar 18b of the chainsaw 18 about a central shaft 18a. When the chainsaw 18 is not in use, the guide bar 18b is stored in the chainsaw unit 16 and faces laterally as shown by an imaginary line in Figure 2. When the chainsaw 18 is in use, the guide bar 18b is rotated about the central shaft 18a with the saw chain 18c driven, and the tip of the guide bar 18b is fed downward in Figure 2. This causes the guide bar 18b of the chainsaw 18 to cross the material to be grappled held by the grapple arms 14, 15, cutting the material.

[0034] Next, the chain saw 18 provided in the chain saw unit 16 will be described with reference to FIG. 5, the chainsaw 18 is fixed to the frame 16a of the chainsaw unit 16. As described above, the chainsaw unit 16 is provided with the frame 16a, the chainsaw 18, and the chainsaw rotation mechanism 24 that rotates the chainsaw 18.

[0035] The chain saw 18 has a saw chain 18c that cuts the material to be grappled, a guide bar 18b that guides the saw chain 18c, and a chain saw motor 18d that drives the saw chain 18c. When cutting, the chain saw 18 is rotated about a central shaft 18a by a chain saw rotation mechanism 24. A sprocket (not shown) that drives the saw chain 18c by the power of the chain saw motor 18d is also provided coaxially with the central shaft 18a.

[0036] The guide bar 18b is a long and thin plate-like member for guiding the saw chain 18c, and is configured so that the saw chain 18c travels around the periphery of the guide bar 18b. The base end of the guide bar 18b is attached to the frame 16a so as to be rotatable about the central shaft 18a.

[0037] Saw chain 18c is a chain attached so as to go around guide bar 18b, and cutting blades (not shown) for cutting wood and the like are provided at predetermined intervals so as to protrude outward. Saw chain 18c is engaged with a sprocket (not shown) provided at the base end of guide bar 18b, and is driven to travel around guide bar 18b by the power of chainsaw motor 18d.

[0038] The chain saw motor 18d is a hydraulic motor for driving the saw chain 18c, and is configured to rotate a sprocket (not shown) by means of supplied hydraulic pressure.

[0039] The chainsaw rotating mechanism 24 is configured to rotate the chainsaw 18 about the central axis 18a. The chainsaw rotating mechanism 24 has a link member 24a attached to the base end of the chainsaw 18 and a hydraulic cylinder 24b connected to the link member 24a. The link member 24a is a long, thin rod-shaped member, and one end of the link member 24a is connected to the base end of the chainsaw 18 so as to be able to rotate.

[0040] The hydraulic cylinder 24b is configured to expand and contract by the hydraulic pressure supplied thereto. The tip of the piston of the hydraulic cylinder 24b is connected to the other end of the link member 24a. Meanwhile, the base end of the hydraulic cylinder 24b is rotatably attached to the frame 16a of the chainsaw unit 16. With this structure, when the piston of the hydraulic cylinder 24b is retracted, the link member 24a pulls the base end of the chainsaw 18, causing the chainsaw 18 to rotate and the guide bar 18b to be extended from the chainsaw unit 16. When the piston of the hydraulic cylinder 24b is extended, the guide bar 18b is stored in the frame 16a of the chainsaw unit 16.

[0041] Next, with reference to FIG. 6, a unit support mechanism, which is a rotation support mechanism that mounts the chain saw 18 to the main body so that the chain saw 18 is capable of elastically swinging, will be described. 6, the unit support mechanism 26 is a mechanism that supports the chainsaw unit 16 relative to the second body portion 12b, and in this embodiment, the frame 16a of the chainsaw unit 16 is supported so as to be elastically swingable relative to the second body portion 12b. This allows the chainsaw 18 to be swingably supported relative to the body portion of the holding and cutting device 10.

[0042] 6, in this embodiment, the unit support mechanism 26 has a unit-side base plate 28a, a main body-side base plate 28b, and a shaft 28c that is a support axis that rotatably connects them. The unit support mechanism 26 further has two compression springs 30a, 30b that are elastic members arranged between the unit-side base plate 28a and the main body-side base plate 28b, a through bolt 32 that extends through these compression springs, and a cylindrical portion 34a and an intermediate plate 34b that are provided to cover the compression spring 30a.

[0043] The unit side base plate 28a is a plate-shaped member fixed to the frame 16a of the chainsaw unit 16. A bracket is provided facing the main body side base plate 28b so as to protrude at a right angle from the unit side base plate 28a. On the other hand, the main body side base plate 28b is a plate-shaped member fixed to the second main body portion 12b. A bracket is provided facing the unit side base plate 28a so as to protrude at a right angle from the main body side base plate 28a.

[0044] The shaft 28c is an axis that rotatably connects the bracket extending from the unit-side base plate 28a and the bracket extending from the main body-side base plate 28b. As a result, the unit-side base plate 28a and the main body-side base plate 28b are connected to be rotatable about the shaft 28c. The shaft 28c is oriented parallel to a plane P that includes the guide bar 18b of the chain saw 18.

[0045] The compression springs 30a, 30b are coil springs arranged in a compressed state between the unit side base plate 28a and the main body side base plate 28b, and are arranged in series so as to extend perpendicularly to these plates.

[0046] The through bolt 32 is a screw that extends through the compression spring 30a, the intermediate plate 34b, the compression spring 30b, and the main body side base plate 28b. The head of the through bolt 32 is located in an opening 28d formed in the unit side base plate 28a. A nut 32a is attached to one end of the through bolt 32, and a washer-shaped pressing plate 32b is disposed on the other end. In this manner, the compression spring 30a is sandwiched between the pressing plate 32b and the intermediate plate 34b, and the compression spring 30b is sandwiched between the intermediate plate 34b and the main body side base plate 28b. The total length of the compression springs 30a and 30b arranged in series is determined by the position of the nut 32a attached to the through bolt 32.

[0047] The tubular portion 34a is a cylindrical portion provided so as to protrude at a right angle from the unit-side base plate 28a so as to surround the compression spring 30a. That is, the tubular portion 34a is fixed to the unit-side base plate 28a so that its central axis is oriented perpendicular to the unit-side base plate 28a, and protrudes toward the main body-side base plate 28b. The tubular portion 34a is also fixed so as to surround the opening 28d provided in the unit-side base plate 28a.

[0048] The intermediate plate 34b is a doughnut-shaped disk fixed to the tip of the cylindrical portion 34a so as to cover the cylindrical portion 34a, and the through bolt 32 extends so as to penetrate the center of the cylindrical portion 34a and the intermediate plate 34b. The intermediate plate 34b is sandwiched between the compression springs 30a and 30b, thereby determining the position of the unit side base plate 28a relative to the main body side base plate 28b. In this embodiment, the compression springs 30a and 30b have the same length in the natural state shown in FIG. 6, and the intermediate plate 34b is sandwiched between these compression springs. As a result, the biasing force of the compression springs 30a and 30b acts on the unit side base plate 28a via the intermediate plate 34b, and the unit side base plate 28a is biased so as to be approximately parallel to the main body side base plate 28b.

[0049] According to this configuration, when the unit side base plate 28a is rotated around the shaft 28c in a direction away from the main body side base plate 28b by an external force, the compression spring 30a arranged on the chainsaw unit 16 side is compressed, and the compression spring 30b arranged on the opposite side is expanded. Conversely, when the unit side base plate 28a is rotated in a direction approaching the main body side base plate 28b by an external force, the compression spring 30b arranged on the second main body portion 12b side is compressed, and the compression spring 30a arranged on the opposite side is expanded. Then, when no external force is applied to the chainsaw unit 16, the biasing forces of the compression springs 30a and 30b on both sides of the intermediate plate 34b are balanced, and the chainsaw unit 16 returns to its natural position shown in FIG. 6.

[0050] In this way, the unit support mechanism 26 supports the chainsaw 18 to be elastically swingable relative to the main body, and the compression springs 30a, 30b, which are elastic members, urge the chainsaw unit 16 to return to a predetermined rotation position. In other words, in the state shown in Figure 6, the guide bar 18b of the chainsaw 18 is located on a plane P parallel to the main body side base plate 28b, and when an external force is applied to swing the chainsaw 18, the guide bar 18b tilts and moves out of the plane P.

[0051] In this embodiment, the unit support mechanism 26 is configured so that when the tip of the guide bar 18b of the chainsaw 18 is pressed with a force of about 40 N, the tip is displaced about 5 mm. Preferably, the unit support mechanism 26 is configured so that when the tip of the guide bar 18b is pressed with a force of about 10 N to about 150 N, the tip is displaced about 15 mm, and more preferably, when the tip of the guide bar 18b is pressed with a force of about 20 N to about 60 N, the tip is displaced about 5 mm. As a result, when cutting a standing tree or the like, the chainsaw 18 changes direction appropriately according to the condition of the wood and cuts forward, and returns to its original direction due to the restoring force of the elastic member.

[0052] By setting the elastic support by unit support mechanism 26 to such a rotational spring constant, guide bar 18b of chainsaw 18 is allowed to change angle appropriately while cutting wood or the like, and even wood with a large diameter can be cut all the way to the end and cut. Note that, although a compression spring (coil spring) is used as the elastic member in this embodiment, other types of springs or members made of elastically deformable materials such as urethane or rubber can be used as the elastic member.

[0053] Next, the operation of the holding and cutting device 10 according to the first embodiment of the present invention will be described with reference to FIG. First, when felling a tree using the holding and cutting device 10 of this embodiment, the vehicle body 2 (FIG. 1) of the work vehicle 1 is rotated to face the vehicle body 2 in the direction of the tree T to be felled. Next, the first working arm 6 and the second working arm 8 are moved to move the holding and cutting device 10 attached to the tip of the second working arm 8 in front of the tree T to be felled. Furthermore, as shown in FIG. 7, the second body part 12b is rotated relative to the first body part 12a so that the chainsaw unit 16 provided on one side of the second body part 12b of the holding and cutting device 10 is positioned below. (That is, the second body part 12b is rotated 90 degrees relative to the first body part 12a from the state shown in FIG. 2.)

[0054] In this state, the holding and cutting device 10 is moved so that the tree T to be felled is placed between the grapple arms 14 and 15. Next, the grapple arms 14 and 15 are rotated so as to approach each other. As a result, the tree T is held by the grapple arms 14 and 15, as shown in FIG. 7. Next, the chainsaw motor 18d (FIG. 5) of the chainsaw 18 is started, and the saw chain 18c begins to be driven. In this state, the hydraulic cylinder 24b (FIG. 5) of the chainsaw unit 16 is retracted, whereby the chainsaw 18 is rotated about the central shaft 18a, and the guide bar 18b is extended toward the held tree. This starts cutting the tree T.

[0055] When cutting into a standing tree T with the chainsaw 18, a force acts on the guide bar 18b to tilt it out of the plane of the guide bar 18b due to the weight of the standing tree T being cut and the cutting resistance. In the holding and cutting device 10 of this embodiment, because the chainsaw 18 is elastically supported, even when such a force is applied, the guide bar 18b can cut the standing tree while changing its angle appropriately, and can cut the standing tree T to the end.

[0056] In contrast, in conventional holding and cutting devices, the chainsaw is firmly fixed in place, so when a force acts on the guide bar to tilt it out of plane, it is necessary to move the guide bar forward against this force, and when trying to cut a thick tree, the guide bar cannot be moved forward halfway, making it difficult to cut the tree to the end.

[0057] Next, after the tree is cut by the holding and cutting device 10 of this embodiment, the chainsaw motor 18d is stopped and the hydraulic cylinder 24b (FIG. 5) of the chainsaw unit 16 is extended, thereby returning the guide bar 18b to its original position. Here, with the holding and cutting device 10 of this embodiment, the tree is cut while being firmly held by the grapple arms 14, 15, so that the tree will not fall in an unexpected direction after it has been cut, and the work can be carried out safely.

[0058] In the holding and cutting device 10 of this embodiment, by turning on a source switch (not shown) provided in the operator's seat 2a (FIG. 1), a series of operations are automatically performed: starting the chainsaw motor 18d, reeling out the guide bar 18b, stopping the chainsaw motor 18d, and returning the guide bar 18b. Furthermore, in the holding and cutting device 10 of this embodiment, oil is continuously supplied to the saw chain 18c while the chainsaw motor 18d is operating, thereby increasing the durability of the saw chain 18c and the guide bar 18b.

[0059] According to the holding and cutting device 10 of the first embodiment of the present invention, the chainsaw 18 is supported on the second body portion 12b so as to be elastically swingable, so that the chainsaw 18 swings slightly when cutting into the grappled material to cut it. This allows the force acting on the guide bar 18b of the chainsaw 18 to be deflected, and the force impeding the movement of the guide bar 18b during cutting is reduced, so that even when cutting a thick grappled material, the chainsaw can be advanced to the end, making it possible to cut the thick grappled material.

[0060] In addition, according to the holding and cutting device 10 of this embodiment, the chainsaw 18 is supported by a unit support mechanism 26 which has a shaft 28c and elastic compression springs 30a, 30b. Therefore, while allowing movement of the chainsaw 18 due to elastic deformation of the compression springs 30a, 30b, the rotation direction of the chainsaw 18 is regulated by the shaft 28c, so that the chainsaw 18 can be caused to oscillate as desired.

[0061] Furthermore, according to the holding and cutting device 10 of this embodiment, the shaft 28c of the unit support mechanism 26 is oriented parallel to the plane P (Figure 6) including the guide bar 18b of the chainsaw 18, so that a swing motion occurs in the guide bar 18b that subtly changes its cutting angle, making it easy to reduce the resistance acting on the guide bar 18b.

[0062] Furthermore, according to the holding and cutting device 10 of this embodiment, the chainsaw unit 16 is attached to the main body portion via the unit support mechanism 26, so that the chainsaw 18 can be elastically swung relative to the second main body portion 12b while using the existing chainsaw unit 16 as is.

[0063] In the holding and cutting device 10 according to the first embodiment of the present invention described above, the chainsaw unit 16 including the chainsaw 18 is fixed to the second body portion 12b via the unit support mechanism 26, thereby supporting the chainsaw 18 so that it can swing elastically. However, as a modified example, the chainsaw 18 itself can be supported so that it can swing elastically.

[0064] Next, a holding and cutting device according to a second embodiment of the present invention will be described with reference to FIG. The holding and cutting device of the second embodiment of the present invention differs from the first embodiment in the mechanism for elastically supporting the chainsaw so that it can swing. Therefore, only the differences between the second embodiment of the present invention and the first embodiment will be described below, and the same configurations, actions, and effects will not be described. Figure 8 is a side view showing the support structure for the chainsaw provided in the holding and cutting device of the second embodiment of the present invention.

[0065] As shown in Fig. 8, in this embodiment, the chainsaw 40 is directly attached to a mounting frame 44 via a translation support mechanism 42. The mounting frame 44 is a frame that constitutes part of the chainsaw unit, and is fixed to a main body of the holding and cutting device (not shown in Fig. 8). When cutting wood, the guide bar 48 of the chainsaw 40 is rotated relative to the mounting frame 44 around the rotation shaft (not shown) of the chainsaw motor 52.

[0066] The chainsaw 40 has a chainsaw body 46, a guide bar 48 attached to the chainsaw body 46, a saw chain 50 wound around the guide bar 48, and a chainsaw motor 52 that drives the saw chain 50. Furthermore, a chainsaw bracket 46a is provided so as to protrude from the periphery of the chainsaw body 46. In this embodiment, the chainsaw bracket 46a is attached to the mounting frame 44 via the translation support mechanism 42.

[0067] The translational support mechanisms 42 are provided on a substantially rectangular chainsaw bracket 46a (only two are shown in FIG. 8). Each translational support mechanism 42 includes a coil spring 42a and a disc spring 42b, which are elastic members, a presser plate 42c, and a through-bolt 42d extending through them.

[0068] A notch 44a for mounting the chainsaw body 46 is formed in the mounting frame 44, and a chainsaw bracket 46a is fixed to the edge of this notch 44a via the translation support mechanism 42. That is, holes 44b for passing through each of the through bolts 42d are formed in the edge of the notch 44a, and the tip of each of the through bolts 42d is passed through these holes 44b and screwed into female screw holes 46b formed in the four corners of the chainsaw bracket 46a.

[0069] Each through bolt 42d is passed through the washer-shaped presser plate 42c and the coil spring 42a, and the coil spring 42a is compressed between the presser plate 42c and the mounting frame 44. The disc spring 42b is disposed between the rear surface of the mounting frame 44 and the chainsaw bracket 46a and is compressed. With this structure, the elastic deformation of the coil spring 42a and the disc spring 42b allows the chainsaw bracket 46a (chainsaw 40) to translate and rotate relative to the mounting frame 44. In other words, the chainsaw 40 is supported so as to be elastically swingable relative to the mounting frame 44 (and the main body fixed thereto).

[0070] That is, when no external force is acting, guide bar 48 of chainsaw 40 is located within plane P in Fig. 8, and when an external force is acting on chainsaw 40, chainsaw 40 swings, and guide bar 48 translates and rotates out of plane P. Then, when the external force is no longer acting on chainsaw 40, it elastically returns to a predetermined translational position due to the biasing forces of coil spring 42a and disc spring 42b, which are elastic members.

[0071] In this embodiment, the translation support mechanism 42 is configured so that the main body of the chainsaw 40 moves in parallel about 5 mm when the main body of the chainsaw 40 is pressed with a force of about 1000 N. Preferably, the translation support mechanism 42 is configured so that the main body of the chainsaw 40 moves in parallel about 5 mm when the main body of the chainsaw 40 is pressed with a force of about 100 N to 2000 N.

[0072] According to the holding and cutting device of the second embodiment of the present invention, the chainsaw 40 is supported on the main body so as to be able to swing elastically, so that the chainsaw 40 swings slightly when cutting into the grappled material to cut it. This allows the force acting on the guide bar 48 of the chainsaw 40 to be deflected, and the force impeding the movement of the guide bar 48 during cutting is reduced, so that even when cutting a thick grappled material, the chainsaw can be advanced all the way to the end, making it possible to cut the thick grappled material.

[0073] Furthermore, according to the holding and cutting device of this embodiment, the translation support mechanism can be configured with a relatively simple structure.

[0074] In the first embodiment of the present invention, the chainsaw unit 16 equipped with the chainsaw 18 is elastically supported so as to be able to swing, and in the second embodiment of the present invention described above, the chainsaw 40 is elastically supported so as to be able to swing on the chainsaw unit mounting frame 44. However, as a modified example, both of these elastic supports may be applied simultaneously.

[0075] That is, in the modification shown in Fig. 9, the chainsaw unit is elastically supported on the main body, and the chainsaw provided on the chainsaw unit is elastically supported on the frame of the chainsaw unit. Specifically, in the modification shown in Fig. 9, the chainsaw unit 16 is supported on the second main body 12b by a rotation support mechanism 60. The chainsaw 18 provided on the chainsaw unit 16 is supported on a mounting frame 62 that constitutes a part of the frame of the chainsaw unit 16 by a translation support mechanism 64. With this configuration, the chainsaw unit 16 is allowed to rotate about the support shaft 60a with respect to the second main body 12b, and the chainsaw 18 provided on the chainsaw unit 16 is allowed to translate and rotate with respect to the mounting frame 62. As a result, the chainsaw 18 is supported by the rotation support mechanism 60 and the translation support mechanism 64 so as to be elastically swingable on the main body.

[0076] Although the embodiment of the present invention has been described above, various modifications can be made to the above-described embodiment. In particular, in the above-described embodiment, the holding and cutting device of the present invention is configured as a grapple saw that is attached to the tip of the working arm of a working vehicle and used, but the present invention can be applied to any device that cuts while holding the grappled material. For example, the present invention can also be applied as a cutting device for a harvester device. Furthermore, the present invention can be used by attaching it to not only the working arm of a working vehicle, but also any device that can move the holding and cutting device so as to hold the grappled material.

[0077] The modified example shown in Figs. 10 and 11 shows an example in which the holding and cutting device of the present invention is applied to a felling work vehicle as a work vehicle. 10 and 11, a felling work vehicle 70 has a holding and cutting device 72 according to an embodiment of the present invention, and a dolly 74 for moving the device. The holding and cutting device 72 is rotatably provided at the front of the dolly 74, and can hold a standing tree T located in front of the dolly 74 with the grapple arms 14, 15.

[0078] As shown in FIG. 10, the standing tree T can be cut by rotating the guide bar 18b of the chain saw 18 provided in the holding and cutting device 72 about the central axis 18a while the standing tree T is held by the grapple arms 14 and 15. At this time, since the chain saw 18 is supported elastically and swingably relative to the main body of the holding and cutting device 72, even a thick standing tree T can be cut while being held by the grapple arms 14 and 15. After the standing tree T is cut, as shown in FIG. 11, the link device 74a provided on the dolly 74 is operated to rotate the entire holding and cutting device 72 forward. This allows the standing tree T to be felled forward while being held by the grapple arms 14 and 15. In this way, since the standing tree T is felled while being held by the grapple arms 14 and 15, the tree does not fall in an unexpected direction, and felling work can be performed safely. [Explanation of symbols]

[0079] 1. Work vehicles 2 Body 2a Cockpit 4 Running part 4a Crawler 6 First working arm 8 Second working arm 8a Hydraulic cylinder 8b Link member 10 Holding and cutting device 10a Hydraulic cylinder 12a First main body part 12b Second main body part 14 Grapple Arm 14a Curved plate section 14b Connecting plate part 15 Grapple Arm 15a Curved plate section 15b Connecting plate part 16 Chainsaw Unit 16a Frame 18 Chainsaw 18a Center axis 18b Guide bar 18c saw chain 18d chainsaw motor 20 Hydraulic cylinder 20a Rotating shaft 22 Hydraulic cylinder 22a Rotating shaft 24 Chainsaw rotating mechanism 24a Link member 24b Hydraulic cylinder 26 Unit support mechanism (rotating support mechanism) 28a Unit side base plate 28b Main unit base plate 28c Shaft (support shaft) 28d aperture 30a, 30b Compression spring (elastic member) 32 Through bolt 32a Nut 32b Presser plate 34a Cylindrical part 34b Intermediate plate 40 Chainsaw 42 Translational support mechanism 42a Coil spring (elastic member) 42b Disc spring (elastic member) 42c Presser plate 42d Through bolt 44 Mounting frame 44a Notch 44b Hole 46 Chainsaw body 46a Chainsaw bracket 46b female thread hole 48 Guide bar 50 Saw Chain 52 Chainsaw Motor 60 Rotating support mechanism 62 Mounting frame 64 Translational support mechanism 70 Felling vehicle 72 Holding and cutting device 74 Trolley 74a Link device

Claims

1. A holding and cutting device that holds and cuts a grappled material, which is a standing tree or wood, A main body portion, A pair of grapple arms rotatably attached to the main body and holding a grappled object; a chainsaw unit attached to the body for cutting a grappled material held by the grapple arms; having The chainsaw unit includes a frame, a chainsaw attached to the frame, and a chainsaw rotation mechanism that rotates the chainsaw so as to cut the material to be grappled; The chain saw is supported in a resiliently swingable manner relative to the main body of the cutting device.

2. The holding and cutting device as described in claim 1, further comprising a pivotal support mechanism that supports the chainsaw so that it can swing elastically relative to the main body, the pivotal support mechanism including a support shaft that supports the chainsaw so that it can swing relative to the main body, and an elastic member that generates a biasing force so that the chainsaw returns to a predetermined pivot position.

3. 3. The cutting device according to claim 2, wherein the support shaft of the pivot support mechanism is oriented parallel to a plane including a guide bar of the chain saw.

4. 3. The cutting device according to claim 2, wherein the chain saw unit is attached to the main body via the pivot support mechanism.

5. 2. The cutting device according to claim 1, further comprising a translational support mechanism that supports the chainsaw so that it can elastically swing relative to the main body, the translational support mechanism allowing translational movement of the chainsaw relative to the main body and including an elastic member that generates a biasing force so that the chainsaw returns to a predetermined translational position.

6. A work vehicle capable of felling or cutting standing trees or timber, A drivable cart; a holding and cutting device according to any one of claims 1 to 5 attached to the carriage; A work vehicle comprising:

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