JP2004082895A - Mounting structure for shift lever in work vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mounting structure for a shift lever in a work vehicle withdrawing an operation lever to a steering wheel side in a neutral position. <P>SOLUTION: The operation lever 18 carrying out changing operation of a traveling direction is protruded by swinging operation from a column 17 of a steering wheel 9 provided in front of a seat 6 in an operating part 7. A withdrawing mechanism is provided for changing the operation lever 18 to a withdrawn attitude A of withdrawing to the steering wheel 9 side when the operation lever 18 is in the neutral position N. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a shift lever mounting structure for a work vehicle such as a tractor.
[0002]
[Prior art]
Conventional work vehicles such as tractors require frequent forward / backward switching when performing front loader work and the like. A model provided with a mechanism is known.
[0003]
In the above model, an operation lever for operating the forward / reverse transmission mechanism to switch the traveling direction (forward / backward) of the aircraft protrudes from a column of a steering handle provided in front of a steering section (driver's seat). The traveling direction of the body can be easily switched by the swing operation of the operation lever.
[0004]
[Problems to be solved by the invention]
However, since the operation lever protrudes from the column of the steering handle (steering column), the operation lever protrudes into the space for getting on and off from the side of the driver's seat. For this reason, the operation lever is switched to the neutral position to stop the machine running, and when the operator gets on and off the vehicle via the above-mentioned space, the operation lever may be erroneously operated due to the operator being stuck on the operation lever. there were.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the shift lever mounting structure of the work vehicle according to the present invention includes a steering handle provided at the front of the seat 6 in the control section 7 with an operating lever 18 for changing the traveling direction by a swing operation. In a working vehicle provided so as to protrude from the column 17 of the actuator 9 and provided with the neutral position N within the swing range of the operation lever 18, the operation lever 18 is retracted toward the steering handle 9 at the neutral position N of the operation lever 18. The first feature is that a retracting mechanism for switching to the posture A is provided.
[0006]
The second feature is that a swing regulating mechanism for regulating the swing of the operation lever 18 in the retreat posture A and fixing the operation lever 18 to the neutral position N in the retreat posture A is provided.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a perspective view of a tractor which is a working vehicle employing the present invention. The tractor has an engine mounted in a hood 2 at the front of an airframe 1 as in the prior art, and is driven by a transmission 10 (see FIG. 2) provided between the engine and front wheels 3 and rear wheels 4. The power is transmitted to the front wheel 3 and the rear wheel 4 by shifting the power to travel, and at the same time, the working machine 5 connected to the rear is driven by supplying a driving force from a PTO output shaft.
[0008]
At this time, a driver's seat 7 (operating portion) having a seat 6 is provided behind the hood 2. The driver's seat 7 has an operation panel 8 and a steering handle 9 in front of the seat 6, and a seat 6. A side operation panel 12 is provided on the fender 11 of the rear wheel 4 on the side of the vehicle, and a main transmission lever 13, an auxiliary transmission lever 14, and a PTO transmission lever 16 are provided on the side operation panel 12 so as to be swingable. I have.
[0009]
The operator (driver) operates the main transmission mechanism in the transmission 10 by the main transmission lever 13 and the sub transmission mechanism in the transmission 10 by the auxiliary transmission lever 14 to change the traveling speed of the body 1. The PTO speed change lever 16 can be used to change the speed of the PTO output shaft via the PTO speed change mechanism so that the drive speed of a working machine such as a rotary cultivator can be changed.
[0010]
On the other hand, the transmission 10 is provided with a forward / reverse speed change mechanism for switching the output rotation direction, that is, the forward and backward movement (running direction) of the body 2 with respect to the drive speed set by the main speed change mechanism and the sub speed change mechanism. From the side of the steering column 17 of the steering handle 9, an operation lever 18 for operating the forward / reverse transmission mechanism to change the traveling direction of the body 2 is bent so that the tip is directed upward and forward and backward, and It is projected to be able to swing up and down.
[0011]
This allows the operator (driver) to easily switch the traveling direction of the body 2 by swinging the operation lever 18 back and forth while operating the steering wheel, and frequently moves forward and backward when performing front loader work or the like. Can be easily and smoothly performed.
[0012]
Next, the support structure of the operation lever 18 will be described in detail. As shown in FIGS. 2 and 3, the operation lever 18 has a lever handle 21 attached to a distal end of a lever rod 19 having a substantially L-shape in a front view. The plate 22 is attached.
[0013]
On the other hand, a fulcrum shaft 24 projects from the panel frame 23 supporting the column shaft of the steering handle 9 and supporting the operation panel 8 in front of the seat 6 toward the left side of the steering handle 9. A boss 27 of a support portion 26 for supporting the operation lever 18 is rotatably supported in the front and rear directions.
[0014]
At this time, the support portion 26 has a structure in which a U-shaped support plate 28 is provided above the boss 27 in a side view, and an arm 29 for operating the forward / reverse transmission mechanism is provided below the boss 27. The plate 22 is pivotally supported between the U-shape of the support plate 28 via a support shaft 31 so as to be rotatable left and right.
[0015]
As a result, the operation lever 18 is supported by the panel frame 23 side so as to be able to swing back and forth about the fulcrum shaft 24 as an axis, and swingable right and left around the support shaft 31 as an axis, and protrudes from the side of the steering column 17. As a result, the lever handle 21 side (tip side) projects upward.
[0016]
The operation lever 18 is integrated with the support portion 26 at the time of forward / backward swing by the above structure, so that the arm 29 is swung by the forward / backward swing, and the forward / reverse speed change mechanism is operated via the arm 29 via a transmission path described later. To switch back and forth. Since the left and right swing is performed with respect to the support plate 28, the swing is independently performed with respect to the support portion 26, and the forward and backward switching operation is not performed by the left and right swing.
[0017]
Further, when the plate 22 swings left and right about the support shaft 31, the distal end and the base end of the lever rod 19 swing up and down along an arc locus. This is vertical swing including horizontal swing along the trajectory, and the forward / backward switching of the operation lever 18 is not performed by the vertical swing. The upward swing of the operation lever 18 causes the lever handle 21 to approach the steering handle 9 side, and the operation lever 18 retreats to the steering handle 9 side.
[0018]
On the panel frame 23 side, a plate-shaped lever guide 32 for guiding the operation lever 18 to swing back and forth is attached, and the base end of the lever rod 19 is inserted into the guide hole 33 of the lever guide 32 to operate. The swing range and direction of the lever 18 are guided. Since the base end of the lever rod 19 extends along the guide hole 33, the front and rear swing of the operation lever 18 is allowed in the range from the front end to the rear end of the guide hole 33.
[0019]
The arm 29 of the support portion 26 and the forward / reverse transmission mechanism move the body 2 forward by positioning the operation lever 18 in the forward position F in which the operation lever 18 is swung forward, and move the operation lever 18 back. It is connected so that the fuselage 2 moves backward when it is located at the position R. Further, the forward / reverse transmission mechanism is provided with a neutral position, and a substantially center of a swing range of the operation lever 18 is a neutral position N of the operation lever 18.
[0020]
In the neutral position of the guide hole 33 where the operation lever 18 is in the neutral position N, the base end of the lever rod 19 is guided in the vertical direction as shown in FIG. A restriction hole 34 is formed in the vertical direction so as to be connected to the guide hole 33. As a result, the operation lever 18 can swing up and down only in the neutral position.
[0021]
At this time, the regulating hole 34 has a size that regulates forward and backward swinging of the operating lever 18 and does not allow forward and backward swinging operation. As a result, when the operating lever 18 is in the neutral position, the base end is in the regulating hole 34. , The swing in the front-rear direction is restricted, and the forward / backward switching operation becomes impossible.
[0022]
On the other hand, a hollow pipe 36 is integrally fixed downward at a position facing the bottom surface of the inner surface of the support plate 28 outside the plate 22 in the lever rod 19, as shown in FIG. A rod 37 is slidably inserted into the pipe 36.
[0023]
A spring 38 for urging the rod 37 downward is inserted into the pipe 36, and urging means is constituted by the pipe 36, the rod 37, the spring 38, and the like. , The portion of the lever rod 19 outside the support shaft 31 is constantly urged upward.
[0024]
Accordingly, the base end of the lever rod 19 is constantly urged downward, and the operation lever 18 is rotated upward by the elastic contact between the lever rod 19 (base end) and the lower end edge of the guide hole 33. Is regulated, and the vertical rotation position of the operation lever 18 is positioned and held.
[0025]
Therefore, in the neutral position, the base end of the operation lever 18 is automatically inserted into the regulating hole 34, swings upward, the tip swings toward the steering handle 9 side, and retracts toward the steering handle 9 side. Then, in a plan view, the operation lever 18 assumes a retreating posture A in which the operation lever 18 is substantially accommodated within the diameter of the steering handle 9.
[0026]
That is, a retracting mechanism for switching the operating lever 18 to the retracting position A is constituted by the urging means and the restriction hole 34 and the like, and automatically switches the operating lever 18 to the retracting position A in the neutral position N. Further, in the retreat posture A, the swinging mechanism including the regulating hole 34 and the base end of the lever rod 19 restricts the swinging of the operating lever 18 in the forward and backward directions, and the operating lever 18 is fixed at the neutral position N.
[0027]
The operating lever 18 is pivoted downward to attain a shifting posture B in which the base end of the lever rod 19 is positioned in the guide hole 34, whereby the operating lever 18 can be pivoted back and forth, and a forward / backward switching operation is performed. Can be performed.
[0028]
As a result, the operator can easily switch the forward / backward running direction of the body 1 by swinging the operating lever 18 forward and backward as described above. However, the forward / backward switching operation is performed by the urging force of the spring 38 and the lever rod 19. When the operation is performed in a state where the guide hole 34 is in contact with the guide hole 34, the operation lever 18 always assumes the retreating posture A during operation, and the swinging back and forth is regulated. An erroneous operation or the like of continuously making changes is prevented.
[0029]
When the operating lever 18 is in the neutral position N, the operating lever 18 is in the retreating position A, so that the amount of protrusion of the operating lever 18 from the side of the seat 6 with respect to the driver's seat 7 to the space for getting on and off is reduced. Since a large space can be ensured, an erroneous operation of the operation lever 18 due to, for example, the operator being hooked on the operation lever 18 when the operator gets on or off the vehicle is prevented.
[0030]
Further, the retracting mechanism and the swing regulating mechanism are constituted by the urging means, the lever rod 19, the regulating hole 34, the guide hole 33 and the like, and the number of parts is small and the structure is simple. Reduced and easy to assemble.
[0031]
On the other hand, as shown in FIG. 2, a relay shaft 42 is rotatably supported on the housing 41 of the transmission case so as to protrude from the left and right sides of the housing 41. The other end of the operated rod 43 is connected to the left end of the relay shaft 42 via an arm 44.
[0032]
An arm 46 provided at the right end of the relay shaft 42 and a shifter arm 47 for operating a forward / reverse speed change mechanism are connected via a rod 48. Is operated to switch back and forth.
[0033]
At this time, the transmission from the operation lever 18 to the shifter arm 47 does not use a wire as in the related art, but has a link structure that is inexpensive in cost. Therefore, the transmission loss of hysteresis due to the wire is eliminated, and the operation feeling is improved. Further, the wire is prevented from being caught and damaged. Since the relay shaft 42 crosses the housing (clutch housing) 41 of the transmission case, the strength of the housing 41 is also reinforced.
[0034]
In the tractor, the levers of the traveling transmission system, that is, the main transmission lever 13, the auxiliary transmission lever 14, and the PTO transmission lever 16 are all concentrated on the left side of the seat 6, and the operation lever 18 is also disposed on the left side of the steering column 17. Therefore, erroneous operation of the lever of the traveling transmission system and the lever of the hydraulic operation system or the like is prevented, and the operability of each lever is high.
[0035]
【The invention's effect】
According to the structure of the present invention configured as described above, the operating lever protruding from the steering column retracts toward the steering handle when in neutral, so that when the operating lever is in the neutral position, the operating lever is used for getting on / off from the side of the seat with respect to the control unit. Since the amount of protrusion of the operation lever into the space can be reduced and the boarding space can be secured large, it is possible to prevent an erroneous operation of the operation lever due to, for example, a worker being caught on the operation lever when the worker gets on and off the vehicle. effective.
[0036]
Also, by providing the swing regulation mechanism, the operation lever is fixed to the neutral position in the retracted posture, so that the operation lever may be erroneously operated even when the operator or the like comes into contact with the operation lever. There is also the advantage of not having it.
[Brief description of the drawings]
FIG. 1 is a side view of a tractor.
FIG. 2 is a rear view of a main part near an operation lever.
FIG. 3 is a side view of a main part near an operation lever.
4A is a front view of a single lever guide, and FIG. 4B is a side view.
FIG. 5 is a sectional view of a biasing mechanism portion of the operation lever.
[Explanation of symbols]
6 Seats 7 Driver's seat (control section)
9 Steering handle 17 Steering (column)
18 Operation lever N Neutral position A Evacuation posture

Claims (2)

An operation lever (18) for changing the traveling direction by a swing operation is provided so as to protrude from a column (17) of a steering handle (9) provided in front of a seat (6) in a control unit (7); In the working vehicle having the neutral position (N) provided within the swing range of the operating lever (18), the operating lever (18) is retracted toward the steering handle (9) at the neutral position (N) of the operating lever (18). The mounting structure of the shift lever in a work vehicle provided with a retreat mechanism for switching to the retracted posture (A). 2. A swing regulating mechanism according to claim 1, further comprising a swing regulating mechanism for regulating swing of the operation lever in the retreating posture, and fixing the operation lever in the neutral position in the retreating posture. Mounting structure of the shift lever in a work vehicle.

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