JP7689726B2 - Offset Machine - Google Patents

Description

The present invention relates to an offset work machine.

Conventionally, mowers are known as working machines that perform grass cutting work to remove weeds from farm roads and wastelands. Generally, mowers are attached to the rear of a traveling body such as a tractor, and proceed with grass cutting work by operating the working unit while moving together with the traveling body. In recent years, offset-type mowers have been known in which the working unit that performs grass cutting work moves offset to the side of the traveling body, and performs grass cutting work to the side of the traveling body. For example, the mowers described in Patent Documents 1 to 3 have an offset mechanism unit composed of a parallel link mechanism between the mounting unit attached to the traveling body and the working unit that performs grass cutting, and the offset mechanism unit enables the offset movement of the working unit.

JP 2018-102223 A JP 2012-39941 A JP 2012-191864 A

Due to the nature of offset work machines, which are operated with the working section protruding significantly to the side of the running body, the position of the center of gravity of the offset work machine differs when working and not working. Therefore, in order to ensure stable operation of the offset work machine, it is important to maintain left-right balance when working and not working.

One of the objectives of the present invention is to efficiently improve the left-right balance of an offset work machine when in operation and when not in operation.

In one embodiment of the present invention, the offset work machine includes a mounting section that can be connected to a traveling machine body, a working section that receives power from the traveling machine body and performs a specified task, a power transmission section that transmits the power from the mounting section to the working section, an offset mechanism section that is disposed between the mounting section and the working section and moves the working section in the left-right direction, and a movable counterweight section that is attached to the mounting section.

The counterweight portion may include a movable support portion and a weight portion supported by the support portion.

The support part may be a folding support part. The support part may be a sliding support part. In this case, the support part may have an actuator that operates the support part.

The support part may be a link-type support part. In this case, the link-type support part may be linked to the operation of the offset mechanism part.

The offset work machine in one embodiment of the present invention can efficiently improve left-right balance during operation and non-operation.

FIG. 1 is a plan view showing a configuration of an offset working machine according to a first embodiment. FIG. 2 is a plan view showing a configuration of the offset working machine of the first embodiment, in which a power transmission unit is not shown. 5A and 5B are enlarged rear views of a counterweight portion in the offset working machine of the first embodiment, in which FIG. 5A shows the deployed state and FIG. 5B shows the stored state. FIG. 11 is a plan view showing a configuration of an offset working machine according to a second embodiment. 13A and 13B are enlarged rear views of a counterweight portion in the offset working machine of the second embodiment, in which FIG. 13A shows the deployed state and FIG. 13A is an enlarged rear view of a counterweight portion of the offset working machine of the third embodiment, (A) showing the deployed state, (B) showing the intermediate state, and (C) showing the stored state. FIG.

The offset work machine according to one embodiment of the present invention will be described below with reference to the drawings. However, the offset work machine according to one embodiment of the present invention can be implemented in many different ways, and should not be interpreted as being limited to the description of the example shown below. In the drawings referred to in this embodiment, identical parts or parts having similar functions are given the same reference numerals, and repeated explanations will be omitted.

In the following explanation, for convenience, terms indicating directions such as "up," "down," "front," "rear," "right," and "left" are used, but for the offset work machine of one embodiment of the present invention, the direction in which gravity acts is "down," and its opposite is "up." Also, the direction in which the traveling body moves is "front," and its opposite is "rear." Furthermore, facing "front," the right side is "right," and the left side is "left." Also, using the center line along the moving direction of the offset work machine as a reference, the direction away from the center line is the outside, and the direction approaching the center line is the inside.

First Embodiment
[Configuration of offset working machine]
1 is a plan view showing the configuration of an offset working machine 100 according to a first embodiment. In this embodiment, an offset type grass cutter is illustrated as an example of the offset working machine 100. However, the offset working machine 100 is not limited to a grass cutter, and may be other offset type working machines such as a ridger or a plow.

As shown in FIG. 1, the offset work machine 100 of this embodiment includes a mounting unit 10, an offset mechanism unit 20, a power transmission unit 30, a working unit 40, and a counterweight unit 50. Specifically, the offset work machine 100 is connected to a traveling machine body (not shown) such as a tractor by the mounting unit 10. The mounting unit 10 and the working unit 40 are connected via the offset mechanism unit 20 and the power transmission unit 30. With this configuration, the offset work machine 100 moves forward as the traveling machine body travels. While the offset work machine 100 moves, the working unit 40 operates by the power received from the traveling machine body and performs grass cutting work.

The mounting unit 10 is a portion that is connected to a three-point link mechanism (not shown) provided on the traveling machine body. Specifically, the mounting unit 10 of this embodiment includes a front frame 11, a top link connection part (top mast) 12 (see FIG. 3), a lower link connection part (lower link pin) 13, an input shaft 14, a power transmission means 15, and an output shaft 16. The top link connection part 12 and the lower link connection part 13 may be connected to the three-point link mechanism of the traveling machine body via an auto hitch arm (not shown). In this embodiment, the output shaft 16 is provided at a position offset from the input shaft 14 in the left-right direction, but this is not limited to this example. For example, the mounting unit 10 may have a structure in which the output shaft 16 is disposed at a position directly behind the input shaft 14. In addition, although not shown, a control unit is provided on the front frame 11 of the mounting unit 10. The control unit includes a calculation processing device, a storage device, a communication device, etc., and has a function of controlling the overall operation of the offset work machine 100.

The offset mechanism 20 is disposed between the mounting unit 10 and the working unit 40, and is a mechanism that moves the working unit 40 in the left-right direction by rotating with respect to the mounting unit 10. In this embodiment, the offset mechanism 20 includes a parallel link mechanism that is rotatably connected to the mounting unit 10 and the working unit 40. That is, by rotating the offset mechanism 20 with respect to the mounting unit 10, the working unit 40 can be moved in the left-right direction while maintaining the orientation of the working unit 40 with respect to the traveling direction. In other words, the offset mechanism 20 can offset the working unit 40 to the side with respect to the traveling direction of the traveling machine body. However, the specific configuration of the offset mechanism 20 is not limited to this example, and it is sufficient if it is a mechanism that can offset the working unit 40 to the side with respect to the traveling direction of the traveling machine body.

Figure 2 is a plan view showing the configuration of the offset work machine 100 of the first embodiment, with the power transmission unit 30 not shown. As shown in Figure 2, the offset mechanism unit 20 of this embodiment has a first link arm 21, a second link arm 22, a third link arm 23, and an actuator 24.

The first link arm 21 is disposed below the power transmission unit 30 shown in FIG. 1. In other words, the power transmission unit 30 is disposed overlapping a portion of the offset mechanism unit 20. One end of the first link arm 21 is rotatably connected to the front frame 11 of the mounting unit 10 via a pivot shaft 410, and the other end of the first link arm 21 is rotatably connected to the third link arm 23 and the working unit 40 via a pivot shaft 420.

The second link arm 22 is disposed approximately parallel to the first link arm 21 at a position spaced apart from the first link arm 21, and has a length similar to that of the first link arm 21. One end of the second link arm 22 is rotatably connected to the front frame 11 of the mounting unit 10 via a pivot shaft 430, and the other end of the second link arm 22 is rotatably connected to the third link arm 23 via a pivot shaft 440.

The third link arm 23 is disposed approximately parallel to the front frame 11 and interconnects the first link arm 21 and the second link arm 22. One end of the third link arm 23 that is connected to the first link arm 21 is fixed to the working unit 40, and is configured so that the positional relationship between the third link arm 23 and the working unit 40 does not change.

With the above configuration, the front frame 11, the first link arm 21, the second link arm 22, and the third link arm 23 form a quadrilateral parallel link mechanism with each of the link arms as a side. With this parallel link mechanism, the offset mechanism unit 20 can offset and move the working unit 40 in the left-right direction while maintaining the orientation of the working unit 40 so that the longitudinal direction of the working unit 40 is approximately parallel to the left-right direction.

The actuator 24 is a power source that operates the offset mechanism 20, and is composed of an expandable member capable of expanding and contracting, such as an electric cylinder, a gas cylinder, or a hydraulic cylinder. One end of the actuator 24 is rotatably connected to the front frame 11, and the other end of the actuator 24 is rotatably connected to the vicinity of the center of the first link arm 21 (or slightly behind the center). The expansion and contraction of the actuator 24 causes the first link arm 21 to rotate about the rotation shaft 410 as a rotation fulcrum, and the offset mechanism 20 operates. The offset amount of the working unit 40 is controlled by the amount of expansion and contraction of the actuator 24.

Referring back to FIG. 1 for the explanation, the power transmission unit 30 is a mechanism for transmitting the power transmitted via the input shaft 14, the power transmission means 15, and the output shaft 16 of the mounting unit 10 to the working unit 40. As described above, the power transmission unit 30 is disposed so as to overlap a part of the offset mechanism unit 20, specifically, the first link arm 21.

The offset work machine 100 of this embodiment uses a chain drive mechanism as the power transmission unit 30. Specifically, the power transmission unit 30 has at least a drive sprocket 31, a driven sprocket 32, and a roller chain 33. The roller chain 33 is configured to be wound around a pair of sprockets (the drive sprocket 31 and the driven sprocket 32).

The driving sprocket 31 is a gear that rotates in engagement with the rotating output shaft 16, and transmits the rotational power received from the output shaft 16. The driven sprocket 32 is a gear that rotates passively by the power transmitted from the driving sprocket 31 via the roller chain 33. The roller chain 33 is a member that transmits power as tension. Note that the power transmission unit 30 is not limited to a chain drive mechanism, and may be configured as a belt drive mechanism using a pair of pulleys and a belt.

The power transmission unit 30 is rotatably connected at the front to the mounting unit 10, and at the rear to the working unit 40. In this embodiment, the center of rotation of the power transmission unit 30 relative to the mounting unit 10 coincides with the center of rotation of the drive sprocket 31. In other words, the center of rotation of the power transmission unit 30 relative to the mounting unit 10 coincides with the center of rotation of the output shaft 16. In addition, the center of rotation of the power transmission unit 30 relative to the working unit 40 coincides with the center of rotation of the driven sprocket 32.

Furthermore, the center of rotation of the power transmission unit 30 relative to the mounting unit 10 coincides with the center of rotation (center of the rotation shaft 410) of the offset mechanism unit 20 (specifically, the first link arm 21) relative to the mounting unit 10. In this manner, in this embodiment, the first link arm 21, which is part of the offset mechanism unit 20, and the power transmission unit 30 rotate integrally relative to the mounting unit 10, which has the advantage that a large offset amount can be ensured without being restricted by the bending angle as occurs when a universal joint is used to transmit power.

The working unit 40 is a part that performs grass cutting work, and has a working rotor 41 and a blade drive unit 42. The working unit 40 performs grass cutting work by driving the working rotor 41 with the blade drive unit 42 receiving power transmitted by the power transmission unit 30. The working rotor 41 includes a claw shaft 41a and multiple cutting blades 41b radially provided on the claw shaft 41a. The claw shaft 41a extends in the left-right direction so as to be approximately perpendicular to the traveling direction of the traveling machine body. The working rotor 41 performs grass cutting by rotating the multiple cutting blades 41b together with the claw shaft 41a. The blade drive unit 42 uses the power transmitted by the power transmission unit 30 as the rotational power of the claw shaft 41a of the working rotor 41. The blade drive unit 42 may be a chain drive mechanism having a configuration similar to that of the power transmission unit 30, or may be a belt drive mechanism.

The counterweight unit 50 is attached to the front frame 11 of the mounting unit 10, and functions as a counterweight (weight) for balancing the weight of the offset work machine 100. In the offset work machine 100 of this embodiment, the working unit 40 moves offset to the right with respect to the traveling direction, so the counterweight unit 50 is disposed on the left side of the front frame 11 with respect to the traveling direction in consideration of the weight balance with respect to the working unit 40. With such a disposition, when the working unit 40 moves offset to the right, the weight unit 52 of the counterweight unit 50 can maintain the balance in the left-right direction.

The counterweight section 50 includes a movable support section 51 and a weight section 52 supported by the support section 51. The support section 51 is fixed to the front frame 11 and has a movable mechanism that changes the position of the weight section 52 in the left-right direction. Specifically, the counterweight section 50 of this embodiment has a structure in which the support section 51 can be bent downward, so that the position of the weight section 52 can be moved outward or inward. In other words, the offset work machine 100 of this embodiment is equipped with a foldable counterweight section 50.

[Counterweight configuration]
Fig. 3 is an enlarged rear view of the counterweight section 50 in the offset work machine 100 of the first embodiment. Specifically, Fig. 3(A) shows a state in which the weight section 52 is moved to the outermost position (hereinafter referred to as the deployed state), and Fig. 3(B) shows a state in which the weight section 52 is moved to the innermost position (hereinafter referred to as the stored state). As shown in Fig. 3(A) and Fig. 3(B), the support section 51 has a connecting arm 51a, a support arm 51b, a weight holding member 51c, and an actuator 51d.

The connecting arm 51a is fixed to the mounting part 10 (front frame 11) and serves to connect the mounting part 10 and the counterweight part 50. The support arm 51b is composed of a rod-shaped member, one end of which is rotatably connected to the connecting arm 51a via a rotating shaft 510, and the other end of which is connected to the weight holding member 51c. As shown in FIG. 1, the connecting arm 51a has a structure in which two plate-shaped members are arranged facing each other, and the support arm 51b is connected via the rotating shaft 510 provided between the plate-shaped members.

The weight holding member 51c is a member for holding each weight (weight) constituting the weight section 52, and has a locking portion (not shown) for locking each weight. Specifically, in this embodiment, a part that functions as a hook is provided on each weight, and each weight is held by hooking the hook to the locking portion of the weight holding member 51c. However, this is not limited to this example, and the method of holding the weight section 52 is arbitrary. That is, the weight holding member 51c only needs to be fixed (or locked) so that the weight section 52 does not fall off during operation of the offset work machine 100. In this embodiment, the weight holding member 51c is configured to be fixed to the support arm 51b, but it is also possible to configure the weight holding member 51c to be positionally adjustable in the left-right direction relative to the support arm 51b. In this case, for example, the support arm 51b is provided with a plurality of fixing holes for fixing the weight holding member 51c with bolts, and the bolt fixing position can be adjusted.

In addition, in this embodiment, an example in which the weight section 52 is composed of multiple weights has been shown, but this is not limiting, and the weight section 52 may be composed of a single weight. When the weight section 52 is composed of multiple weights, it is possible to increase or decrease the number of weights as appropriate according to the offset amount of the working section 40, and adjust the balance in the left-right direction.

The actuator 51d is a power source that bends the counterweight section 50, and is composed of an expandable member capable of expanding and contracting, such as an electric cylinder, a gas cylinder, or a hydraulic cylinder. One end (cylinder side) of the actuator 51d is rotatably connected to the connecting arm 51a via a rotating shaft 520, and the other end (rod side) is connected slightly behind the center of the support arm 51b (for example, below the weight section 52). The operation of the actuator 51d is controlled by a control section (not shown), and the amount of expansion and contraction of the actuator 51d , i.e., the amount of rotation of the support arm 51b relative to the connecting arm 51b, is controlled based on a control signal transmitted from the control section.

When the actuator 51d expands and contracts, the support arm 51b rotates vertically around the pivot shaft 510 relative to the connecting arm 51a, changing the position of the weight section 52. Specifically, when the actuator 51d expands, the support arm 51b rotates upward (clockwise here) and assumes the deployed state (Fig. 3(A)). In the deployed state, the weight section 52 is positioned at the outermost side. When the actuator 51d contracts, the support arm 51b rotates downward (counterclockwise here) and assumes the stored state (Fig. 3(B)). In the stored state, the weight section 52 is positioned at the innermost side.

In this embodiment, when the offset amount of the offset mechanism 20 is maximized during operation, that is, when the working unit 40 is positioned at the outermost position (to the right side in the direction of travel), the counterweight unit 50 is set to the deployed state shown in FIG. 3(A). Specifically, when the offset amount of the offset mechanism 20 is maximized (or exceeds a predetermined offset amount), the above-mentioned control unit controls the actuator 51d to extend, and the counterweight unit 50 is placed in the deployed state. This allows the center of gravity, which has shifted outward to the right due to the offset movement of the working unit 40, to be returned to the left by the weight unit 52 of the counterweight unit 50, thereby adjusting the left-right balance.

Conversely, when the offset amount of the offset mechanism 20 is minimized during non-operation, that is, when the working unit 40 is located at the innermost position (left side in the direction of travel) (strictly speaking, when it is located directly behind the mounting unit 10), the counterweight unit 50 is set to the stored state shown in FIG. 3(B). Specifically, when the offset amount of the offset mechanism 20 is minimized (or falls below a predetermined offset amount), the above-mentioned control unit controls the actuator 51d to contract, and the counterweight unit 50 is stored. As a result, when the working unit 40 is close to the center line of the offset work machine 100 (i.e., when there is almost no shift in the center of gravity due to the offset movement), the weight unit 52 of the counterweight unit 50 is brought closer to the center line, and the shift in the center of gravity to the outside in the left direction due to the weight unit 52 can be prevented. The offset amount of the offset mechanism 20 is grasped by appropriately providing a sensor or the like that detects the angle of the link arm 21 or the link arm 22 relative to the front frame 11. For example, a potentiometer can be provided at one end of the second link arm 22 connected to the pivot shaft 430 to detect and calculate the angle of the second link arm 22 relative to the front frame 11. It is also possible to grasp the offset amount of the offset mechanism unit 20 by providing a sensor that detects the amount of rotation of the pivot shaft 420.

As described above, the offset work machine 100 of this embodiment is equipped with a movable counterweight unit 50, which allows the left-right position of the weight unit 52 to be changed according to the offset amount of the working unit 40, thereby efficiently improving the left-right balance during work and non-work.

(Modification of the first embodiment)
In the above-described first embodiment, an example is shown in which the counterweight unit 50 is set to either the deployed state (FIG. 3A) or the stored state (FIG. 3B) by the extension and retraction operation of the actuator 51d, but the present invention is not limited to this example. For example, the offset working machine 100 of the first embodiment can also set the counterweight unit 50 to an intermediate state between the deployed state and the stored state by adjusting the drive amount (extension and retraction amount) of the actuator 51d.

In this modification, the control unit controls the actuator 51d to adjust the drive amount of the actuator 51d according to the offset amount of the offset mechanism 20. That is, in the offset work machine 100 of this modification, when the offset amount of the offset mechanism 20 changes, the drive amount of the actuator 51d changes according to the offset amount, and the position of the weight section 52 is controlled so that the weight balance of the offset work machine 100 is optimized. The correspondence relationship between the offset amount of the offset mechanism 20 and the drive amount of the actuator 51d may be stored in advance in the storage device of the control unit as a table or a relational expression. The drive amount of the actuator 51d is controlled based on the angle of the support arm 51b relative to the connecting arm 51a detected by an angle sensor such as a potentiometer.

Second Embodiment
In this embodiment, an example in which the movable method of the counterweight part is different from that of the first embodiment will be described. Specifically, the offset work machine of this embodiment is equipped with a sliding counterweight part. In this embodiment, the differences from the first embodiment will be focused on, and the same parts as those of the first embodiment will be indicated by the same reference numerals in the drawings, and duplicated explanations will be omitted.

Figure 4 is a plan view showing the configuration of the offset work machine 200 of the second embodiment. Figure 5 is an enlarged rear view of the counterweight section 55 in the offset work machine 200 of the second embodiment. Specifically, Figure 5(A) shows the state in which the weight section 57 has been moved to the outermost position (deployed state), and Figure 5(B) shows the state in which the weight section 57 has been moved to the innermost position (stored state).

As shown in Figures 4 and 5, the counterweight section 55 includes a movable support section 56 and a weight section 57 supported by the support section 56. In this embodiment, the counterweight section 55 has a structure in which the support section 56 is expandable and contractible in the left-right direction, so that the position of the weight section 57 can be slid outward or inward (toward the center of the offset work machine 200) relative to the center of the offset work machine 200. In other words, the offset work machine 200 of this embodiment is equipped with a sliding counterweight section 55.

The support unit 56 has a first support arm 56a, a second support arm 56b, a weight holding member 56c, and an actuator 56d. The first support arm 56a is a hollow tubular member having an opening of a first diameter, one end of which is fixed to the mounting unit 10, and the other end of which is connected to the second support arm 56b. The second support arm 56b is a hollow tubular member having an opening of a second diameter smaller than that of the first support arm 56a, one end of which is connected to the first support arm 56a, and the other end of which is connected to the weight holding member 56c. The second support arm 56b is inserted into the first support arm 56a and is movable inside the first support arm 56a. In other words, the support unit 56 has a telescopic structure composed of the first support arm 56a and the second support arm 56b.

The weight holding member 56c is a member for holding each weight (weight) that constitutes the weight section 57, similar to the first embodiment.

The actuator 56d is a power source that slides the counterweight section 55, and is composed of an expandable member such as an electric cylinder, a gas cylinder, or a hydraulic cylinder that can expand and contract. One end of the actuator 56d is connected to the first support arm 56a, and the other end is connected to the vicinity of the center of the second support arm 56b. The expansion and contraction of the actuator 56d causes the second support arm 56b, which has a telescopic structure, to move inside the first support arm 56a, and the (apparent) lengths of the first support arm 56a and the second support arm 56b, i.e., the position of the weight section 57 in the left-right direction relative to the center position of the offset work machine 100, change. Specifically, when the actuator 56d expands, the second support arm 56b protrudes from the first support arm 56a and expands outward, becoming an expanded state (FIG. 5(A)). When the actuator 56d contracts, the second support arm 56b is inserted inside the first support arm 56a, becoming a stored state (FIG. 5(B)).

In this embodiment, as in the first embodiment, when the offset amount of the offset mechanism 20 is maximum during operation, the counterweight 55 is set to the deployed state shown in FIG. 5(A), and when the offset amount of the offset mechanism 20 is minimum during non-operation, the counterweight 55 is set to the stored state shown in FIG. 5(B). In this way, the offset work machine 200 of this embodiment can change the left-right position of the weight 57 depending on the offset amount of the working unit 40, so that the left-right balance during operation and non-operation can be efficiently improved.

(Modification of the second embodiment)
In the above-described second embodiment, an example is shown in which the counterweight section 55 is set to either the deployed state (FIG. 5(A)) or the stored state (FIG. 5(B)) by the extension and contraction operation of the actuator 56d, but the present invention is not limited to this example. That is, similar to the modified example of the first embodiment, in this modified example, it is possible to set the counterweight section 55 to an intermediate state between the deployed state and the stored state by adjusting the drive amount (extension and contraction amount) of the actuator 56d. That is, the drive amount of the actuator 56d may be adjusted according to the offset amount of the offset mechanism section 20, and the position of the weight section 57 may be controlled so that the weight balance of the offset work machine 200 is optimized.

Third Embodiment
In this embodiment, an example in which the movable method of the counterweight part is different from that of the first and second embodiments will be described. Specifically, the offset work machine of this embodiment is equipped with a link-type counterweight part. In this embodiment, the differences from the first embodiment will be focused on, and the same parts as those of the first embodiment will be indicated by the same reference numerals in the drawings, and duplicated explanations will be omitted.

Figure 6 is a plan view showing the configuration of the offset work machine 300 of the third embodiment. Specifically, Figure 6(A) shows the state in which the weight section 62 has been moved to the outermost position (deployed state), Figure 6(B) shows the state in which the weight section 62 has been moved between the deployed state and the stored state (intermediate state), and Figure 6(C) shows the state in which the weight section 62 has been moved to the innermost position (stored state).

As shown in FIG. 6, the counterweight section 60 includes a movable support section 61 and a weight section 62 supported by the support section 61. In this embodiment, the counterweight section 60 can move the position of the weight section 62 outward or inward in the left-right direction by the support section 61 functioning as a link mechanism that is linked to the operation of the offset mechanism section 20. In other words, the offset work machine 300 of this embodiment is equipped with a link-type counterweight section 60.

The support section 61 has a connecting arm 61a, a support arm 61b, a weight holding member 61c, and a link arm 61d. The connecting arm 61a is fixed to the mounting section 10 and serves to connect the mounting section 10 and the counterweight section 60. The support arm 61b is composed of a rod-shaped member, one end of which is rotatably connected to the connecting arm 61a via a rotating shaft 610, and the other end of which is connected to the weight holding member 61c. As in the first embodiment, the connecting arm 61a has a structure in which two plate-shaped members are arranged facing each other, and the support arm 61b is connected via a rotating shaft 610 provided between the plate-shaped members.

The weight holding member 61c is a member for holding each weight (weight) that constitutes the weight section 62, similar to the first embodiment.

The link arm 61d is a rod-shaped member having a bent portion 61da. One end of the link arm 61d is rotatably connected to the support arm 61b via a pivot shaft 620, and the other end is rotatably connected to the second link arm 22 of the offset mechanism unit 20 via a pivot shaft 630. As shown in FIG. 6C, the bent portion 61da is provided near the pivot shaft 620 provided at the end of the support arm 61b. In addition, the pivot shaft 610, which is the connection portion between the connecting arm 61a and the support arm 61b, is located closer to the weight holding member 61c than the pivot shaft 620, which is the connection portion between the link arm 61d and the support arm 61b. At this time, the distance between the pivot shaft 610 and the pivot shaft 620 is longer than the distance between the bent portion 61da and the pivot shaft 620.

The counterweight unit 60 of this embodiment has the above-mentioned link structure, so that the left-right position of the weight unit 62 changes in conjunction with the operation of the offset mechanism unit 20. In other words, the counterweight unit 60 of this embodiment changes the left-right position of the weight unit 62 in conjunction with the offset amount of the working unit 40.

Specifically, when the offset amount of the working unit 40 is maximum in a plan view, the support arm 61b is in the deployed state (Fig. 6(A)). Then, when the working unit 40 moves inward and the offset amount becomes smaller as shown in Fig. 6(B), the link arm 61d is pushed diagonally upward to the left in conjunction with the operation of the offset mechanism unit 20, and the support arm 61b rotates backward (counterclockwise in this case). At this time, the rotation angle of the support arm 61b also changes in accordance with the change in the offset amount, and after passing through the intermediate state shown in Fig. 6(B), it finally reaches the stored state shown in Fig. 6(C) when the offset amount of the working unit 40 is minimum.

In this embodiment, as in the first embodiment, when the offset amount of the offset mechanism unit 20 is maximum during work, the counterweight unit 60 is set to the deployed state, and when the offset amount of the offset mechanism unit 20 is minimum during non-work, the counterweight unit 60 is set to the stored state. In this way, the offset work machine 300 of this embodiment can change the left-right position of the weight unit 62 according to the offset amount of the working unit 40, so that the left-right balance during work and non-work can be efficiently improved.

Although the present invention has been described above with reference to the drawings, the present invention is not limited to the above-mentioned embodiments (including modified examples), and can be modified as appropriate without departing from the spirit of the present invention. For example, a person skilled in the art can add, delete, or modify components as appropriate based on each embodiment, and this is included in the scope of the present invention as long as it satisfies the gist of the present invention. Furthermore, the above-mentioned embodiments can be combined as appropriate as long as there are no mutual contradictions, and technical matters common to each embodiment are included in each embodiment even if not explicitly stated.

Even if there are other effects and advantages different from those brought about by the aspects of each of the above-mentioned embodiments, if they are clear from the description in this specification or can be easily predicted by a person skilled in the art, they are naturally understood to be brought about by the present invention.

10...mounting portion, 11...front frame, 12...top link connecting portion, 13...lower link connecting portion, 14...input shaft, 15...power transmission means, 16...output shaft, 20...offset mechanism portion, 21...first link arm, 22...second link arm, 23...third link arm, 24...
Actuator, 30...power transmission section, 31...driving sprocket, 32...driven sprocket, 33...roller chain, 40...working section, 41...working rotor, 41a...claw shaft, 41b...cutting blade, 42...cutting blade drive section, 50, 55, 60...counterweight section, 51, 56, 61...support section, 52, 57, 62...weight section, 51a, 61a...connecting arm, 51b, 61b...support arm, 61da...bending section, 56a...first support arm, 56b...second support arm, 51c, 56c, 61c...weight holding member, 51d, 56d...actuator, 61d...link arm, 100, 200, 300...offset working machine, 410, 420, 430, 440, 510, 520, 610, 620, 630...rotating shaft

Claims (7)

A mounting part that can be connected to the traveling body;
A working unit that receives power from the traveling machine body and performs a predetermined task;
a power transmission unit that transmits the power from the mounting unit to the working unit;
An offset mechanism unit that is disposed between the mounting unit and the working unit and rotates about an axis in the vertical direction relative to the mounting unit to offset the working unit laterally with respect to the traveling direction of the traveling body;
A movable counterweight portion attached to the mounting portion;
Equipped with
The counterweight portion includes a weight portion,
An offset work machine, wherein the weight portion is movable in a direction opposite to a direction of the offset movement of the working portion. The offset work machine according to claim 1, wherein the counterweight section moves the weight section according to the offset amount of the work section. The counterweight portion includes a drive means.
3. The offset working machine according to claim 1, wherein the driving means moves the weight section in response to the offset movement of the working section. The offset work machine according to claim 3, wherein the driving means is an actuator. The offset work machine according to claim 1, wherein the counterweight section includes a foldable support section that supports the weight section. The offset work machine according to claim 1, wherein the counterweight section includes a sliding support section that supports the weight section. A mounting part that can be connected to the traveling body;
A working unit that receives power from the traveling machine body and performs a predetermined task;
a power transmission unit that transmits the power from the mounting unit to the working unit;
an offset mechanism that is disposed between the mounting unit and the working unit and rotates about an axis that is vertical to the mounting unit to offset and move the working unit in the left-right direction;
A movable counterweight portion attached to the mounting portion;
Equipped with
The counterweight portion includes a movable support portion and a weight portion supported by the support portion,
The support part is a link-type support part that is linked to the operation of the offset mechanism part.

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