Work vehicle

Abstract

To provide a working vehicle capable of surely locking an operation lever.SOLUTION: In the work vehicle including the operation lever 15 operable in the front-rear direction and the left-right direction and the lock operation means 30 configured to switch between the locked state for restricting the operation of the operation lever 15 and the unlocked state, the lock operation means 30 includes the lock operation portion 31, the engagement portion 32 configured to operate in conjunction with the lock operation portion 31, and the locking portion 33 configured to receive the engagement portion 32, and the engagement portion 32 and the locking portion 33 are configured to face each other at a plurality of positions. The engaging part 32 is formed of a plurality of engaging rods 32a, 32b, the locking part 33 is formed of locking holes 33a, 33b corresponding to the engaging rods, and one engaging rod 32a of the plurality of engaging rods is used as a turning fulcrum to turnably provide the other engaging rod 32b.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a work vehicle such as a tractor equipped with a front loader. [Background technology]

[0002] A known configuration is one that includes a locking hole provided in a mounting bracket at the base of an operating lever that can swing back and forth and left and right, and a locking rod that is supported on a support bracket at a position corresponding to the locking hole so that it can slide axially, and that can be switched between a locked state in which it is inserted into the locking hole to lock, and an unlocked state in which it is removed from the locking hole to release the lock (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-133669 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above technology, if the locking hole is small, the locking rod cannot be inserted smoothly into the locking hole, and if the locking hole is large, a gap will form between the hole and the rod even when locked. Therefore, it was not possible to reliably lock the operating lever without increasing the precision of the parts.

[0005] The present invention provides a work vehicle that can reliably place an operating lever in a locked state. [Means for solving the problem]

[0006] In order to solve the above problem, the invention described in claim 1 is a work vehicle that is provided with an operating lever 15 that can be operated in the forward / backward and left / right directions, and a lock operating means 30 that switches between a locked state and an unlocked state to regulate the operation of this operating lever 15, wherein the lock operating means 30 comprises a lock operating portion 31, an engaging portion 32 that interlocks with this lock operating portion 31, and a locking portion 33 that receives the engaging portion 32, and the engaging portion 32 and the locking portion 33 are configured to face each other at multiple points.

[0007] The invention described in claim 2 is the invention described in claim 1, in which the engagement portion 32 is a plurality of engagement rods 32a, 32b, the locking portion 33 is a corresponding locking hole 33a, 33b, and one of the plurality of engagement rods, 32a, is arranged as a rotation fulcrum and the other engagement rod 32b is rotatable.

[0008] The invention described in claim 3 is the invention described in claim 2, in which the multiple engaging rods 32a, 32b are connected in parallel by a connecting arm plate 32c, one of the multiple engaging rods 32a is configured to be rotatable around the other engaging rod 32b, and a regulating member 37 is provided to regulate the swinging of the connecting arm plate 32c. [Effects of the Invention]

[0009] According to the first aspect of the present invention, the engaging portions 32 are configured to face each other at a plurality of locations, so that the operating lever 15 can be locked reliably.

[0010] According to the invention of claim 2, in addition to the effect of claim 1, one of the multiple engagement rods, 32a, is provided as a pivot point around which the other engagement rod, 32b, is pivotable, so that the engagement rod 32a on the pivot point side is fixed and is less likely to become misaligned with the opposing locking hole. The operation of driving the first joint 725 can be linked to the first link mechanism 723.

[0011] According to the invention as set forth in claim 3, in addition to the effect of claim 2, excessive movement of the engagement rod 32b on the rotated side can be restricted, and the reliability at the time of locking can be improved. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a side view of a tractor according to an embodiment of the present invention. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. 4 is a front view of the operating lever lock operating means. [Figure 5] FIG. 10 is a perspective view showing the operation lever in a locked state. [Figure 6] FIG. 10 is a perspective view showing the operation lever in an unlocked state. DETAILED DESCRIPTION OF THE INVENTION

[0013] An embodiment of the present invention will be described with reference to the drawings.

[0014] Figures 1, 2 and 3 show a tractor equipped with a front loader 3 at the front as an example of a work vehicle, and in this tractor T, the rotational power of an engine mounted inside the hood at the front of the body 1 is transmitted to a transmission in a transmission case 2, and the rotational power is reduced by this transmission and transmitted to front wheels 4 and rear wheels 5. A steering wheel 6 for steering the left and right front wheels 4, 4 is mounted behind the engine, and a driver's seat 7 is located behind it.

[0015] The front loader 3 is equipped with a boom 11 that moves up and down by a hydraulic lifting cylinder 10, a bucket 13 that is pivotally supported at the tip of the boom 11 and swings up and down by a hydraulic up and down cylinder 12, a control valve body 14 that controls the extension and retraction of each of the cylinders 10, 12, and an operating lever 15 that controls the valve of the control valve body 14.

[0016] The operating lever 15 is provided so as to be swingable in the front-rear and left-right directions. Operating the operating lever in the front-rear direction controls the extension and retraction of the hydraulic lifting cylinder 10, and operating it in the left-right direction controls the extension and retraction of the hydraulic up-down cylinder 12.

[0017] The control valve body 14 is disposed, for example, on the right side of the body frame 11. The control valve body 14 includes a boom lifting valve 18 and a bucket rotating valve 19. The boom lifting valve 18 drives and controls the hydraulic lifting cylinder 10 to raise and lower the front loader 3. The bucket rotating valve 19 drives and controls the hydraulic up and down cylinder 12 to rotate the bucket of the front loader 3.

[0018] Next, the support structure and function of the operating lever 15 will be described in detail. A bracket member 20 is fixed to one side (the right side in the illustrated example) of the vehicle body 1, and a support shaft 21 having a vertical axis is mounted on this support shaft 21. A universal joint 22 is mounted on this support shaft 21. This universal joint 22 is connected to a base plate 23 that supports the operating lever 15, forming a movable part that allows the operating lever 15 to be operated in any direction. The operating lever 15 is mounted to an appropriate position on the upper part of the base plate 23 so as to extend obliquely via a seat plate 15a. A link mechanism is mounted on the underside of the base plate 23 to form a front loader operating connection section. Specifically, horizontal support shafts 24, 25 are mounted at two locations on the underside of the base plate 23, spaced 90 degrees apart from each other. One of the horizontal support shafts, 24, is equipped with a connecting rod 26 to connect the spool 18a of the boom-lifting valve 18, and the other horizontal support shaft 25 is equipped with a connecting rod 27 to connect the spool 19a of the bucket rotation valve 19. Therefore, when the operating lever 15 is rotated in the forward / backward direction, the connecting rod 26 side is pushed or pulled in the longitudinal direction, and by interlocking the spool 18a, it is possible to control the boom-lifting valve 18. Furthermore, when the operating lever 15 is rotated in the left / right direction, the connecting rod 27 side is operated, and by interlocking the spool 19a, it is possible to control the bucket rotation valve 19.

[0019] Next, the lock operation means for the operating lever 15 will be described. As shown in FIG. 4, the lock operation means 30 switches between a locked state and an unlocked state. In the locked state, the movement of the operating lever 15 is restricted to prevent the boom 11 from moving up and down or the bucket 13 from rotating uncontrollably. Specifically, the lock operation means 30 comprises a lock operation portion 31, an engagement portion 32 interlocked with the lock operation portion 31, a locking portion 33 that receives the engagement portion 32, and a restricting portion 34 that restricts excessive movement of the engagement portion. As shown in FIGS. 5 and 6, a block-shaped engagement portion 33 having locking holes 33a and 33b formed at multiple locations (two locations in the illustrated example) is fixed to the end of the base plate 23. Two engaging rods 32a and 32b are provided to face the locking holes 33a and 33b. The two engaging rods 32a and 32b are integrally connected in parallel to form the engagement portion 32.

[0020] The engaging portion 32 is guided in a predetermined position by a restricting portion 34 consisting of a guide member 34a and a restricting plate 34b. That is, the guide member 34a is made of a pipe material appropriately fixed to the vehicle body 1, and one of the two engaging rods, 32a, is inserted and held in the guide member 34a. The restricting plate 34b is provided with a hole 34c facing the locking hole 33b, and the other engaging rod 32b is provided so as to be insertable and removable through the hole 34c, and is guided so as to engage with the locking hole 33b when inserted through the hole 34c. The two engaging rods 32a, 32b are connected in parallel by a connecting arm plate 32c, so that the other engaging rod 32b can rotate around the engaging rod 32a, which is inserted and supported by the pipe material, and the connecting arm plate 32c can swing up and down. A U-shaped first regulating member 35 is provided in the middle of the connecting arm plate 32c to regulate the swing range, and a second regulating member 37 is provided near the engaging rod 32b.

[0021] A lever-shaped lock operating portion 31 is provided to slide the engaging portion 32 along the guide member 34a. A tension spring 36 is provided between the lock operating portion 31 and the vehicle body fixed portion, and biases the intermediate portion of the connecting arm plate 32c so as to abut against the upper piece of the U-shaped first restricting member 35, and biases the rod of the engaging portion 32 toward the locking hole of the locking portion 33.

[0022] The upper end of the second restricting member 37 abuts against the engaging rod 32b, thereby restricting the swing range of the engaging rod 32b and guiding the end of the engaging rod 32b to enter the hole 34c.

[0023] Therefore, as shown in Fig. 6, the engaging rods 32a, 32b are normally away from the locking holes 33a, 33b, and the connecting arm plate 32c is biased by the spring 36 into a state in which it abuts against the upper piece of the first restricting member 35, thereby establishing an unlocked state. On the other hand, as shown in Fig. 5, when the lock operating portion 31 is grasped and the engaging rod 32b of the engaging portion 32 is rotated so that it is aligned with the hole 34c of the restricting plate 34b, both the engaging rods 32a, 32b enter and pass through the locking holes 33a, 33b, respectively. This pass-through state fixes the base plate 23, establishing a locked state.

[0024] In the unlocked state, the end of the engaging rod 32b is released from the hole 34c, and the opposing positions of the hole 34c and the engaging rod 32b are maintained in a misaligned state by the bias of the spring 36, so that the engaging rod 32b cannot advance in the locking direction unexpectedly. In the locked state, the bias of the spring 36 can maintain the state in which the engaging rods 32a and 32b pass through the locking holes 33a and 33b.

[0025] Here, with regard to the shape of the locking holes 33a, 33b of the locking portion 33, since the relationship between the locking portion 32 and the locking portion 33 is provided in two places as shown in the example, the locking holes 33a, 33b can be formed in a shape that makes it easy for the tip ends of the engaging rods 32a, 32b to enter, i.e., with a slightly larger diameter; in other words, the tolerance range can be set slightly larger, which prevents the engaging rods from being gouged when entering the locking holes and makes locking operation easy.

[0026] Furthermore, when a pair of locking holes 33a, 33b are used, both can be formed as long hole-shaped locking holes, and by making one of them a horizontally long hole and the other a vertically long hole, it is possible to restrict lever operation in any direction, front to back, left to right, and right to left, and by forming the long holes, it is possible to widen the entrance receiving surface of the engaging rods 32a, 32b. [Explanation of symbols]

[0027] 15 Operating lever 30 Lock operation means 31 Lock operation section 32 Engagement part 32a Engagement rod 32b Engagement rod 32c connecting arm plate 33 Locking part 33a Locking hole 33b Locking hole 35 First restricting member 37 Second restricting member

Claims

1. A work vehicle is provided with an operating lever (15) that can be operated in the forward / backward and left / right directions, and a lock operating means (30) that switches between a locked state and an unlocked state to regulate the operation of the operating lever (15), wherein the lock operating means (30) comprises a lock operating part (31), an engaging part (32) that interlocks with the lock operating part (31), and a locking part (33) that receives the engaging part (32), and the engaging part (32) and the locking part (33) are configured to face each other at multiple points.

2. 2. A work vehicle as described in claim 1, wherein the engaging portion (32) is a plurality of engaging rods (32a, 32b), the locking portion (33) is a corresponding locking hole (33a, 33b), and one of the plurality of engaging rods (32a) is provided as a pivot point for the other engaging rod (32b).

3. 3. A work vehicle according to claim 2, wherein the plurality of engaging rods (32a, 32b) are connected in parallel by a connecting arm plate (32c), one of the plurality of engaging rods (32a) is configured to be rotatable around the other engaging rod (32b), and a restricting member (37) is provided to restrict the swinging of the connecting arm plate (32c).

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