JP2018047860A - Operation implement of working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an operation implement of a working vehicle which can obtain a desired detent force with respect to a full-operation stroke of a traveling gear change lever, and can prevent an easy erroneous operation.SOLUTION: An operation implement of a working vehicle comprises a positioning mechanism 42 or the like for positioning and locking a traveling gear change lever 23 in a plurality of irregular engagement operation positions. The positioning mechanism 42 has a specified recessed part 59a wider than the other part in a groove width out of a plurality of recessed parts 59 which are formed at an oscillation member 41 or an elastic member 38, and aligned in a circular shape with a lever support shaft 37 as a pivot, has a detent force larger than the other part by irregularly engagement-operating a protrusive part 54 in a groove of the specified recessed part 59 while having an elastic force, and positions and locks the traveling gear change lever 23.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an operating tool for a work vehicle provided with a positioning mechanism for a travel shift lever.

2. Description of the Related Art Conventionally, an operating tool for a work vehicle has been provided with a positioning mechanism for positioning operation positions at a plurality of locations on the lower end side of a traveling speed change lever that is swing-operated about a fulcrum shaft, and positions the traveling speed change lever at a plurality of predetermined operation positions However, as shown in Patent Document 1, it is already known.
The operating tool includes a swing member having a movable surface that is swing-operated integrally with the traveling speed change lever, and an elastic member having a fixed surface that is spaced apart from and close to the movable surface. A positioning mechanism for positioning the traveling speed change lever is compactly formed by forming a concave portion and a convex portion to be combined, and providing either one of the concave portion and the convex portion in an arc shape with the support shaft as a fulcrum. In addition, it is possible to easily set the increase / decrease of the positioning position of the traveling speed change lever. In addition, since the operation load of the traveling speed change lever is set by the elastic force of the elastic member, the operation load is less likely to vary and the maintenance is facilitated.

JP, 2015-127154, A

The operating tool of the work vehicle disclosed in Patent Document 1 facilitates maintenance work because the operating load of the traveling speed change lever is set by the elastic force of the elastic member while the positioning mechanism of the traveling speed change lever is more compact. There are advantages such as. However, this positioning mechanism can stably hold the traveling speed change lever at the neutral position and perform positioning operation at the highest speed position or a predetermined speed position with high use frequency quickly and accurately with a large detent force. Difficult to operate and required problems such as skill.
That is, the positioning mechanism includes a concave portion corresponding to the neutral position formed on the swing member and a concave portion at all shift positions (total shift stroke range) from the lowest forward / rearward speed position adjacent thereto to the highest speed position. Therefore, the detent force generated by engaging each concave portion with the convex portion is equalized. For this reason, when the operator accidentally touches the traveling gearshift lever in the neutral position or involves an inadvertent operation, the traveling gearshift lever is liable to malfunction, and the operator moves the traveling gearshift lever from the high speed traveling position. When performing an inadvertent return operation to the neutral position, there is a problem in that it is easy to overlook the neutral position where it is difficult to obtain a detent feeling, and causes an erroneous operation such as re-execution of the neutral position return operation of the traveling speed change lever.
Also, for example, there is a characteristic that the force in the return direction of the travel shift lever (hereinafter simply referred to as lever return reaction force) increases as the travel shift lever is operated in a high speed range, such as HST and belt type continuously variable transmissions. In a transmission, if the detent force at the concave portion corresponding to the highest speed side at which the lever return reaction force is maximum is obtained by increasing the elastic force of the spring member to increase the detent force, When operating in the high speed range, there is a drawback that the operating load of the traveling speed change lever in the low speed range where the lever return reaction force is small becomes large. When the speed change lever from the high speed position to the low speed position or the return operation toward the neutral position (lever return operation) is to be performed quickly, the operator feels a weak detent force on the high speed side but is strong on the low speed side. There is also a problem that a feeling of discomfort such as detent drag is felt, and the operating force of the travel shift lever is different in each shift range of the entire operation stroke, so that a uniform operation feeling cannot be obtained and the operability is impaired.

In order to solve the above problems, the present invention firstly has a swing member 41 having a traveling speed change lever 23 that swings and operates with a lever support shaft 37 as a fulcrum, and the swing member 41 is directed in the direction of the swing axis. The movable surface 41a is provided with an elastic member 38 that has a fixed surface 38a that is opposed to or in contact with the movable surface 41a, and that is curved and deformed in the direction of separation and proximity to the movable surface 41a. On one side, a convex portion 54 is formed, and on the other side, a concave portion 59 that engages with the convex portion 54 is formed, and either the convex portion 54 or the concave portion 59 is supported by a lever. In an operating tool for a work vehicle, provided with a plurality of arrangements arranged in an arc shape with a shaft 37 as a fulcrum, and a positioning mechanism 42 for positioning and locking the traveling shift lever 23 at a plurality of concave and convex engagement operation positions,
Among the concave portions 59 formed on the rocking member 41 or the elastic member 38 and arranged in a circular arc shape with the lever support shaft 37 as a fulcrum, a specific concave portion 59a having a wider groove width than the others is provided. A positioning mechanism that positions and locks the traveling speed change lever 23 with a larger detent force than the others by operating the convex portion 54 in the groove of the specific concave portion 59a with an elastic force. 42 is constituted.
Secondly, the groove 59 of the concave portion 59 corresponding to the neutral position of the shift of the traveling speed change lever 23 is widened so that the specific concave portion 59a having a larger detent force than other positions is obtained.
Thirdly, by increasing the groove width of the concave portion 59 corresponding to the high speed side from the low speed side of the traveling speed change lever 23, the detent force is gradually increased toward the high speed side. It is characterized by doing.

According to the first aspect of the present invention, in the operation tool of the work vehicle including a positioning mechanism that positions and locks the traveling speed change lever at the plurality of concave and convex engagement operation positions, the lever is formed on the swing member or the elastic member. Among a plurality of concave portions provided side by side in an arc shape with a shaft as a fulcrum, a specific concave portion having a wider groove width than the others is provided, and the convex portion has an elastic force in the groove of the specific concave portion. By constructing a positioning mechanism for positioning and locking the traveling speed change lever with a larger detent force than the others by operating the concave and convex,
Among the plurality of concave portions formed on the swing member or the elastic member, the convex portion can be elastically engaged with the specific concave portion having a groove width wider than the other, and the other can be The traveling shift lever can be accurately positioned and locked with a large detent force. Accordingly, the positioning mechanism can obtain a desired detent force with a simple configuration in which the groove width of the specific concave portion at the desired shift position is made wider than the other grooves with respect to the entire operation stroke of the traveling speed change lever. . Therefore, in this case, the positioning mechanism is operated by a large detent force when the operator carelessly operates the traveling gearshift lever in the neutral position or when the operator accidentally touches and involves an erroneous operation. Since the operator is conscious of proper operation, easy erroneous operation can be prevented and operational stability can be improved.
According to the invention of claim 2, by widening the groove width of the concave portion corresponding to the shift neutral position of the travel shift lever, by making the specific concave portion with a larger detent force than other positions,
Since the convex part is deeply fitted into the concave part at the neutral position that is wider than the other parts to increase the concave / convex engagement force, the traveling shift lever is stably positioned and held with a detent force larger than that of other grooves. . Therefore, in this case, the positioning mechanism is operated by a large detent force when the operator carelessly operates the traveling gearshift lever in the neutral position or when the operator accidentally touches and involves an erroneous operation. Since the operator is consciously urged to perform appropriate operations, easy erroneous operations can be prevented and operational stability can be improved. In addition, the positioning mechanism that provides the specific concave portion at the neutral position improves the accuracy of the neutral position return operation by a simple configuration in which the groove width H of the concave portion corresponding to the neutral position is made wider than that of the neighboring concave portion. In addition, erroneous operation can be prevented.
According to a third aspect of the invention, the detent force is gradually increased toward the high speed side by gradually increasing the groove width of the concave portion corresponding to the high speed side from the low speed side of the traveling speed change lever. By making it concave,
This positioning mechanism increases the detent force by setting a predetermined concave portion to a desired wide width in response to the characteristic that the lever return reaction force increases as the high speed operation inherent in the transmission such as HST is performed. Therefore, a high-performance positioning mechanism with good operability can be provided with a simple and inexpensive configuration without greatly changing the structure or increasing the elastic force of the spring member to increase the operation load.

It is a side view of the riding type transplanter to which the present invention is applied. It is a principal part front view which shows the speed change operation apparatus to which this invention is applied. It is a principal part side view which shows the structure of a travel speed change lever and a rocking | swiveling member. The structure of a pair of left and right spring members is shown, (a) is a side view of the right spring member, and (b) is a side view of the left spring member. It is a schematic diagram which shows the engagement cross-section aspect of a rocking | swiveling member and a spring member. The engagement cross section aspect of a rocking | swiveling member and a spring member is shown, (a) is a principal part front view which shows the engagement state of the right spring member, (b) is the principal part which shows the engagement state of the left spring member. It is a front view.

  An embodiment of the present invention will be described with reference to the drawings. First, reference numeral 1 in FIG. 1 denotes a riding type transplanter shown as an example of a work vehicle. The transplanter 1 includes a traveling machine body 3 supported by a pair of left and right front wheels 2 and a rear wheel 2a, and the traveling machine body 3. A planting work machine 5 supported so as to be movable up and down via a link mechanism 4 at the rear part, and a seedling transporting device 6 for a spare seedling extending from the front side of the traveling machine body 3 to the planting work machine 5 side. I have.

  The traveling machine body 3 includes an engine (not shown) disposed on the front side of the machine body frame 7 and a control unit 9 provided behind the bonnet 8 that covers the engine. Are transmitted to the front wheels 1 and the rear wheels 2 through the HST 11, the transmission unit 12, the front axle case 13, and the like fixed to the engine side.

  The steering unit 9 includes a seat 16 on which an operator is seated. A front operation panel 18 in which various operating tools such as a steering handle 17 are installed is disposed in front of the seat 16. A floor step 19 serving as a floor surface is formed between the two.

  The front operation panel 18 is connected to the transmission unit 12 side by a steering device 21 extending from the steering handle 17 toward the lower front side. Further, a travel speed change lever 23 for performing a travel speed change operation by swinging back and forth is disposed on one side of the steering handle 17 in the left-right direction (left side in the illustrated example). An operation display unit for displaying instruments is provided.

  The traveling speed change lever 23 is operated via the speed change operation device 26, and thus is moved through the HST 11 by a forward swinging operation from a state in which it is tilted from the neutral position to one side in the left-right direction (right side in the illustrated example). A stepless speed increase operation to the forward travel side is performed, and a stepless speed increase operation to the reverse travel side through the HST 11 is performed by a backward swing operation from a state tilted from the neutral position to the left and right other side. . A guide member 27 is provided in the middle of the travel speed change lever 23. The guide member 27 guides the above-described operation of the traveling speed change lever 23 by a front-rear crank shape guide hole 27a formed in the guide plate, and positions the traveling speed change lever 23 at a plurality of predetermined operation positions. Can do.

  The planting work machine 6 includes a seedling mounting base 28 that is steeply inclined upward toward the front, and a planting unit 29 disposed below the seedling mounting base 28. The engine power is intermittently transmitted from the traveling machine body 3 side to the planting work machine 6 through the planting transmission shaft 31 by the planting clutch. The planting part 29 is driven by the engine power transmitted in this way, and the seedlings on the seedling mount 28 are scraped off and planted in the field by the driven planting part 29.

  The shift operation device 26 includes a support bracket 36 that is detachably attached to upper and lower horizontal support frames 33 and 34 fixed to a shaft member 32 of the steering device 21, and a left and right side of the support bracket 36 (in the illustrated example). A lever support shaft 37 extending to the left), a spring member 38, which is a plate-like elastic member attached to the lever support shaft 37 side, and the lower end side of the traveling speed change lever 23 are connected to each other and inward in the left-right direction. And a U-shaped bracket 39 formed in a U-shape with an opening, and a swinging member 41 (swinging bracket) that connects the U-shaped bracket 39 to the support bracket 36 so as to swing back and forth.

  Then, the operating position of the entire operation stroke of the traveling speed change lever 23 (swinging member 41) swinging back and forth around the lever support shaft 37 is set to a predetermined operation at the opposite part of the both members by the swinging member 41 and the spring member 38. A positioning mechanism 42 for positioning at a position (shift range) is configured. The positioning mechanism 42 includes a concave portion (locking hole) 59 formed on the movable surface 41a of the swinging member 41 that swings back and forth, and a spring fixed to the lever support shaft 37 side so as to face the movable surface 41a. A convex portion (locking piece) 54 provided on the fixed surface 38a of the member 38 is configured as described later. The support bracket 36 includes a gear member 46 and a potentiometer 47 that transmit the shaft rotation of the shaft member 32 inside a frame-shaped member formed in a rectangular frame shape, and detects the operation position of the steering handle. A strike position detecting means 48 is installed.

  The lever support shaft 37 is a shaft member having a screw portion projecting from the left and right side (left side in the illustrated example) to the left and right in the left and right sides of the rectangular frame-shaped support bracket 36. A pipe-like boss member 51, a pair of left and right spring members 38, and a plate-like swinging member 41 disposed so as to be sandwiched between the spring members 38 are inserted into the lever support shaft 37. The liner 52 is inserted into the facing surface side (facing portion) of the spring member 38 and the swing member 41 and the outermost surface of the spring member 38, and each member is tightened by a nut 55 that is screwed to the screw portion. Worn. (See Figure 6)

  The left and right spring members 38 have a D-shaped attachment hole 53 (rotation restricting mechanism) inserted through the lever support shaft 37 on the center side. According to the mounting hole 53 having this shape, the D-shaped mounting hole 53 is inserted into the lever support shaft 37, thereby restricting the spring member 38 from rotating around the lever support shaft 37. The arc-shaped spring member 38 is formed by punching so that the upper and lower portions each form a semi-arc-shaped ring portion, leaving the center where the mounting hole 53 is formed, and the movable surface 41a of the swing member 41 is formed. On the outer peripheral side of the fixed surface 38a that faces the convex portion 54, a convex portion 54 that can be engaged with the concave portion 59 is formed as follows.

  That is, as shown in FIG. 4A, the right spring member 38 has a concave portion 59 formed symmetrically above and below the left and right center line (vertical line) S of the upper and lower ring portions. Further, as shown in FIG. 4B, the left spring member 38 has a diameter in which the concave portion 59 is arranged with a half phase of the predetermined interval of the concave portions 59 arranged in parallel to the swing member 41 in a plurality of arcs. It is formed in a symmetrical shape above and below the line S1. As a result, the positioning mechanism 42 can easily increase the number of positioning positions of the traveling speed change lever 23. The left and right spring members 38 project the projecting cross-sectional shape of each convex portion 54 so as to form an isosceles triangular mountain shape, as indicated by a solid line in FIG. As a result, each convex portion 54 is positioned at a depth where the protrusion slopes on both sides abut the corner portions on both front and rear sides of the groove width, with the top portion positioned at the center of the groove width H of the concave portion 59. While engaging in a mountain-valley shape, it engages with an elastic force, and positioning is performed by a detent force due to this engagement.

  On the other hand, the convex portion 54 in the positioning state has a strong contact reaction force (operational force) between the projecting slope and the corner portion when an operation force in the front-rear direction indicated by a thick arrow in FIG. The ring portion of the spring member 38 is elastically deformed and moved in the direction indicated by the thick dotted line arrow (the direction of disengagement) by the component force of the operation drag while being elastically deformed by the drag). Detach from the groove. As a result, the swinging member 41 whose positioning engagement has been released can freely swing in the operating direction. The swinging member 41 during swinging movement can swing in a sliding state in which the movable surface 41a is elastically pressed by the top of the convex portion 54, and the concave portion 59 in the next order is provided. When reaching the top of the convex portion 54, the operator senses the detent force due to the engagement between the two through the traveling speed change lever 23, and the positioning operation of the traveling speed change lever 23 can be accurately performed while recognizing the detent position. .

  Next, a specific structure of the swing member 41 will be described with reference to FIGS. The swinging member 41 forms a swinging bracket by a plate-like member that is long in the vertical direction, and has a shaft hole 56 through which the lever support shaft 37 is inserted at the center side of the member. The swinging member 41 is supported so as to be swingable around the fulcrum shaft 37 (front-rear direction) by inserting the lever support shaft 37 through the shaft hole 56, and is attached to the lower end side in a supported state. A trunnion rod 57 for operating the HST 11 is connected via the.

  The swinging member 41 has a pipe-shaped boss member 58 fixed on the upper end side in the front-rear direction, and a U-shaped bracket 39 having the traveling speed change lever 23 is connected via the boss member 58. . Accordingly, as shown in FIG. 3, the swinging member 41 has the trunnion rod 57 according to the shift range around the lever support shaft 37 at each position from the neutral position N to the forward shift position F and the reverse shift position R. Thus, the HST 11 can be operated by a mechanical configuration via the control to perform an appropriate shift.

In the swing member 41, a concave portion 59 that engages the top of the convex portion 54 protruding from the spring member 38 in a fitted state is drawn up and down around the shaft hole 56 with the same radius as the convex portion 54. On the arc line, a plurality of arcs are arranged side by side by a groove arrangement positioning structure having a predetermined interval (pitch) and a groove width as described later.
The positioning mechanism 42 including the spring member 38 and the swinging member 41 can swing the swinging member 41 integrally around the lever support shaft 37 by the forward / backward swinging operation of the traveling speed change lever 23, and the movable surface 41a. The concave portion 59 on the side moves around the lever support shaft 37 in an arc shape. As a result, the convex portion 54 on the fixed surface 38a side biased toward the movable surface 41a is selectively fitted to the plurality of concave portions 59, so that the swing operation position of the traveling speed change lever 23 is changed. Positioned. Further, since the positioning mechanism 42 includes a plate-like swinging member 41 and a pair of plate-like spring members 38 and 38 disposed so as to sandwich the plate-like swinging member 41, the entire apparatus can be configured compactly. .

  Further, the U-shaped bracket 39 is connected to the swinging member 41 via a fulcrum bolt 61 in the front-rear direction with the upper side of the swinging member 41 facing between the front and rear mounting pieces. A tension spring 66 is provided between the moving member 41 and the U-shaped bracket 39. The travel speed change lever 23 of the speed change operation device 26 having the above-described configuration can swing left and right with a fulcrum bolt 61 as a fulcrum via a U-shaped bracket 39, and the travel speed change lever 23 is biased inward in the left and right direction by a tension spring 66. As a result, it is possible to swing in the left-right direction at the neutral position, and the traveling speed change lever 23 is biased inward in the left-right direction, so that the swinging operation to the front side can be performed smoothly.

  Further, the traveling speed change lever 23 is configured so that it cannot be swung to the rear side, which is the reverse side, only after the traveling speed change lever 23 is operated to the left and right outside against the urging force of the tension spring 66. Incorrect operation can be prevented. When the traveling speed change lever 23 is operated to a neutral position N, a forward position F, a reverse position R, etc., as in the prior art, a positioning mechanism 42 comprising a swinging member 41 and a spring member 38 is used to move in the front-rear direction. Can be positioned with a predetermined detent force at a plurality of positions (each shift range).

  Next, a specific structure of the groove arrangement positioning means of the concave portion 59 will be described with reference to FIGS. First, FIG. 5 is a developed plan sectional view showing an embodiment of the groove arrangement positioning means of the concave portion 59 formed in the swing member 41 by an arc arrangement. A mode is shown in which the forward shift position grooves F1, F2 and the reverse shift position grooves R1, R2 are formed by the same-shaped grooves at substantially upper symmetrical positions. FIG. 6A is a front view showing a state in which the forward first speed groove F1 of the swing member 41 is engaged with the convex portion 54 of the right spring member 38 based on the operation of the traveling speed change lever 23. 6B is a front view showing a state in which the forward first speed groove F2 of the swing member 41 is engaged with the convex portion 54 of the left spring member 38. FIG.

  As shown in FIG. 5, the groove arrangement structure of the positioning mechanism 42 according to the embodiment includes, as a specific concave portion 59 a, a concave portion 59 that is positioned at the neutral position N among the plurality of concave portions 59 formed in the swing member 41. The groove width H is made wider than the other grooves, and the groove width of the concave portion 59 from the specific concave portion 59a to the forward highest speed position groove 59e and the reverse highest speed position groove 59e is formed so as to increase gradually. ing. Accordingly, the positioning mechanism 42 has a predetermined engagement depth with the convex portion 54 with respect to the speed change groove position of each concave portion 59 in the forward operation direction, for example, as schematically shown in FIG. The detent force can be made larger than the others in the specific concave portion 59a that can be engaged and the groove width H is widened, so that the positioning stability at the neutral position N of the traveling speed change lever 23 and the operability described later are improved. Yes.

  That is, the positioning mechanism 42 in the illustrated example has a groove arrangement structure in which the groove width of each concave portion 59 is formed wide so that the detent force sequentially increases from the low speed side of the traveling speed change lever 23 toward the high speed side of the speed change. In other words, the concave portion 59 corresponding to the neutral position N is set as the maximum width as the specific concave portion 59a, and the groove width of the concave portion 59 corresponding to the first forward position F1, R1 of the lowest forward / reverse speed adjacent thereto is minimized. The groove widths are formed so as to increase gradually from the adjacent concave portions 59 toward the concave portions 59e at the highest speed shift positions Fe and Re. In other words, the positioning mechanism 42 is configured to increase the detent force sequentially toward the shift high speed side by sequentially widening the groove width of the concave portion 59 corresponding to the shift high speed side from the shift low speed side of the travel shift lever 23. A concave portion 59a is provided.

As a result, the positioning mechanism 42 of the embodiment improves the operational feeling of the traveling speed change lever 23 in the entire operation stroke, corresponding to the characteristic that the lever return reaction force is increased as the HST 11 inherently performs the high speed range operation. Can be achieved. That is, the positioning mechanism 42 changes the conventional structure greatly or the spring member 38 in order to increase the detent force by setting the concave portion 59 to a desired wide width corresponding to the operation characteristics of various transmissions such as HST11. The high-performance positioning mechanism 42 with good operability can be manufactured with a simple and inexpensive configuration without increasing the elastic force of the lens and increasing the operation load.
In the illustrated example, the positioning mechanism 42 has a configuration in which the convex portion 54 formed on the spring member 38 is engaged with the concave portion 59 formed on the rocking member 41. The convex portion 54 formed on 41 and the concave portion 59 formed on the spring member 38 may be configured to elastically engage with each other.

  In the transplanter 1 including the operation tool configured as described above, the positioning mechanism 42 of the traveling shift lever 23 is arranged in parallel in an arc direction with a lever support shaft 37 formed on the swing member 41 or the elastic member 38 as a fulcrum. Among the plurality of concave portions 59, a specific concave portion 59a having a groove width different from that of the other concave portions 59 is provided, and different detent forces are obtained by elastically engaging the convex portion 54 with the specific concave portion 59a. The travel speed change lever 23 can be positioned and locked. As a result, the transplanter 1 allows the specific concave portion 59a at the desired shift position (shift range) to be operated with respect to the entire operation stroke of the traveling speed change lever 23 that is performed by elastically engaging the convex portion 54 with the concave portion 59a. The desired detent force can be easily obtained by making the groove width different from that of the other shift ranges.

  That is, as described above with reference to FIG. 5, the positioning mechanism 42 of the operating tool is configured so that the groove width H of the concave portion 59 at the neutral position N is made wider than the others as the specific concave portion 59 a, thereby As shown by the solid line, since the engagement force is increased by deeply fitting into the large groove of the specific concave portion 59a, the traveling speed change lever 23 can be reliably positioned and held with a larger detent force than the other grooves. . Therefore, the positioning mechanism 42 is provided with a large detent of the specific concave portion 59a when the operator carelessly operates the traveling speed change lever 23 at the neutral position N, or when the operator accidentally touches and involves an erroneous operation. The easy operation of the travel shift lever 23 is regulated by force and the operator is consciously urged to perform proper operation. Therefore, erroneous operation and malfunction can be prevented, and the operation stability of the travel shift lever 23 can be improved. .

  Also, when the travel shift lever 23 is returned from the high-speed travel position to the neutral position N, when the operator performs an inadvertent operation or an inexperienced operation that overlooks the neutral position N, the groove width is increased at the neutral position N. The concave portion 59a makes it difficult to easily jump over the neutral position N because the operator can sense the detent force by reliably engaging the top of the convex portion 54 in the wide groove. Therefore, the positioning mechanism 42 that provides the specific concave portion 59a at the neutral position N has a simple configuration in which the groove width H of the concave portion 59 corresponding to the neutral position N is made wider than that of the neighboring concave portion 59, so that the neutral position It is possible to improve the operability by improving the accuracy of the return operation and preventing erroneous operation.

  Furthermore, the transplanter 1 is adapted to the characteristic that the lever return reaction force increases as the travel shift lever 23 is operated to the high speed side, which is inherent to the transmission such as the HST 11. Since the groove width of the concave portion 59 corresponding to the high speed side from the low speed side is increased gradually, the positioning mechanism 42 is provided with the specific concave portion 59a in which the detent force is sequentially increased toward the high speed side. When the travel speed change lever 23 is operated to the high speed side, the lever return reaction force that gradually increases is maximized while the positioning of the travel speed change lever 23 is ensured by the detent force corresponding to each operation position of the concave portion 59 that becomes wider gradually. Smooth movement to the high speed side can be achieved.

  Next, when the traveling speed change lever 23 is returned from the maximum speed position to the low speed side, the lever return reaction force that is sequentially reduced over the entire stroke is applied to the positioning resistance by the detent force in which the concave portions 59 are sequentially reduced. When the operator performs the return operation for all strokes, the operator operates the travel speed change lever 23 smoothly with uniform operation force and operation feeling without feeling uncomfortable such as fluctuation of the return operation force unlike the conventional one. be able to. In addition, since the appropriate detent force can be recognized for each shift range during the return operation, the positioning of the travel shift lever 23 to the desired low-speed side position can be greatly changed, or the elastic force of the spring member 38 can be increased to increase the operating load. There is a feature that it can be easily and reliably realized by a simple and inexpensive configuration without increasing the value.

  The specific concave portion 59a having the above-described action is not limited to the neutral position N, but is operated in a high speed range, for example, a transmission such as HST11 or a belt type continuously variable transmission. In the case of the positioning mechanism 42 of the traveling speed change lever 23 although the reaction force in the returning direction of the traveling speed change lever 23 (hereinafter simply referred to as lever return reaction force) is large, the concave portion 59 at the high speed region position is designated as the specific concave portion. 59a can be a wide groove. In addition, when it is necessary to position the traveling speed change lever 23 in a specific travel area due to the work characteristics of the work vehicle, the concave portion 59 at the specific speed shift position may be a wide groove as the specific concave portion 59a.

1 Working vehicle (Transplanter)
23 Traveling lever 37 Front / rear fulcrum shaft (support shaft)
38 Spring member (elastic member)
38a Fixed surface 41 Oscillating bracket (oscillating member)
41a Movable surface 42 Positioning mechanism 53 Mounting hole (rotation restricting mechanism)
54 Convex part (locking piece)
59 Concave part (locking hole)
59a Specific concave part

Claims (3)

A swing member (41) having a traveling speed change lever (23) swinging about a lever support shaft (37), and a movable surface (41a) facing the swing axis of the swing member (41) Provided with an elastic member (38) that has a fixed surface (38a) that is opposed to or in contact with the movable surface (41a) and that is curved and deformed in a separated / proximal direction with respect to the movable surface (41a). A convex portion (54) is formed on one of the fixed surfaces (38a), and a concave portion (59) that engages with the convex portion (54) is formed on the other side. 54) or concave portions (59) are arranged in a plurality of arcs with the lever support shaft (37) as a fulcrum, and the travel speed change lever (23) is positioned and locked at a plurality of concave and convex engagement operating positions. In an operating tool for a work vehicle including a positioning mechanism (42),
Among the concave portions (59) formed on the rocking member (41) or the elastic member (38) and arranged in a circular arc shape with the lever support shaft (37) as a fulcrum, the groove width is larger than the others. By providing a wide specific concave portion (59a) and engaging the convex portion (54) with an elastic force in the groove of the specific concave portion (59a), the detent force is greater than the others. An operating tool for a work vehicle, characterized in that it comprises a positioning mechanism (42) for positioning and locking the travel transmission lever (23).   The specific concave part (59a) having a larger detent force than other positions by widening the groove width of the concave part (59) corresponding to the neutral position of the shift of the traveling speed change lever (23). Operation tool for work vehicles.   By increasing the groove width of the concave portion (59) corresponding to the shift high speed side from the shift low speed side of the travel shift lever (23) in order, the detent force (59a) is gradually increased toward the shift high speed side. 3. A work vehicle operating tool according to claim 1 or 2.

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