JP2004090885A - Switching mechanism of forward/backward travel change lever - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate complexity and high cost of an assembly structure, which is caused by connecting a reverse lever to a rotating body through a link rod and a link joint, simplify a link mechanism of the reverse lever, and save a space near a steering column. <P>SOLUTION: A switching mechanism is constituted by arranging the reverse lever 18 switching forward and backward movement on a dashboard 16 near a steering handle 13 and arranging an operation transmitting mechanism for the reverse lever 18 in the dashboard 16. A base part of the reverse lever 18 is mounted on a reverse shift shaft 24 vertically disposed and the reverse lever 18 can be rotated in front and rear directions. A rotating arm 30 is fixed on the reverse shift shaft 24 and one end of the rotating body 19 having axes in front and rear directions or in left and right directions is linked and coupled with the rotating arm 30. The reverse lever is connected to a forward/backward clutch through a transmitting mechanism from the rotating body 19. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an interlocking mechanism of an operation lever, for example, to a structure of a connecting mechanism of a reversing lever arranged in parallel with a steering section of a traveling vehicle such as a tractor.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a work vehicle such as a tractor, a shift operation has been performed by changing the rotation in the front-rear direction to a push-pull operation of a link. For example, a technique is known in which a reversing lever (a forward / backward switching lever) is disposed in an operating unit, and the reversing lever is operated back and forth to switch between forward and marching.
[0003]
As the link mechanism of the reversing lever, a technique of connecting using a universal joint or the like (for example, see Patent Document 1) and a technique of a link connecting mechanism using a link joint are known.
An outline of a link connecting mechanism of a conventional reverser lever using a link will be described with reference to FIGS.
FIG. 5 is a front view showing a link mechanism of a conventional reverser lever, and FIG. 6 is a plan view of the same.
The structure of the reversing lever is such that, when the reversing lever 18 is operated in the front-rear direction around the reversing shift shaft 24 serving as a rotation fulcrum shaft, the reversing shift shaft 24 is interlockedly rotated via the connecting member 22, whereby the reversing shift is performed. A turning arm 30 fixed to the shaft 24 turns around the reverser shift shaft 24. A connecting pin 32 is inserted and fixed to the rotating arm 30, a link spherical joint 42a is connected to the other end of the connecting pin 32, and the link spherical joint 42a is integrally formed with one end of the link rod 41, A link spherical joint 42b is integrally formed at the other end, and one end of the rotating body 19 is pivotally connected to the link spherical joint 42b. The rotating body 19 is formed in a bell crank shape and a rotating shaft 43 is disposed at a central portion to be rotatable. A connecting link 39 is connected to the other end of the rotating body 19, and the other end of the connecting link 39 Was connected to the front-rear switching clutch.
[0004]
Further, the reverser lever is connected to the operating shaft, the lower portion of the operating shaft is connected to the arm via a telescopic pipe, a universal joint, and the like, and the rotation of the arm is connected to the forward / reverse clutch (see FIG. 1). For example, see Patent Document 1.)
[0005]
[Patent Document 1]
JP-A-9-286341
[0006]
[Problems to be solved by the invention]
However, in the conventional link mechanism of the reversing lever using the joint, when switching the forward / backward movement of the body, it is necessary to interpose the link rod and the link joint before transmitting the movement of the reversing lever to the rotating body. . In addition, there was little space around the dashboard and the links were around. Therefore, a space for interposing the link rod and the link joint is required, which leads to an increase in the number of parts, resulting in an increase in cost and a complicated assembling configuration.
In addition, the technique of Patent Document 1 requires a telescopic pipe, a universal joint, and the like, and has a complicated structure and an increased number of parts.
[0007]
Therefore, in the present invention, in order to solve the above-mentioned conventional problems, in a link mechanism of a reversing lever in a traveling vehicle, an assembly configuration is provided by being connected via a link rod and a link joint between the reversing lever and the rotating body. An object of the present invention is to eliminate the complexity and high cost, to simplify the link mechanism of the reverser lever and to save space near the steering column.
[0008]
[Means for Solving the Problems]
The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.
[0009]
That is, in the first aspect, the reverser lever for switching between forward and backward is arranged on the dashboard near the steering handle, and the operation transmission mechanism of the reverser lever is arranged in the dashboard. The base is attached to a reverser shift shaft provided in the up-down direction to be rotatable in the front-rear direction, a turning arm is fixed to the reverser shift shaft, and a turning body having a front-back or left-right axis in the turning arm is provided. It is linked to one end, and is connected to the forward / reverse clutch by the rotating body via a transmission mechanism.
[0010]
According to a second aspect of the present invention, a connecting pin protrudes from the rotating arm, and the connecting pin is slidably disposed on a connecting shaft rotatably provided on the rotating body.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the invention will be described.
FIG. 1 is a side view of a tractor provided with a link mechanism of a reverser lever according to the present invention, FIG. 2 is a front view showing a link mechanism of the reverser lever, FIG. 3 is a side view thereof, and FIG. is there.
[0012]
First, a schematic configuration of a tractor 1 which is an embodiment of a work vehicle equipped with a reverser lever link mechanism of the present invention will be described with reference to FIG.
The tractor 1 is provided with an engine frame 21 at a front end of a vehicle body, a front wheel 3.3 is supported at a lower front portion of the engine frame 21 via a front axle case, and a transmission case fixed to a rear end of the engine frame 21. 9, rear wheels 4 are supported via a rear axle case.
[0013]
At the front of the engine frame 21, an engine 5 is mounted via an anti-vibration member on an engine support member fixed to the engine frame 21, and a radiator 6 and a battery 7 are provided in front of the engine 5. Are located. The engine 5, the radiator 6, the battery 7, and the like arranged in the engine room are covered with the hood 8. A dashboard 16 is disposed behind the hood 8, and a steering handle 13 is disposed above the rear end of the dashboard 16. One side of the steering handle 13 (to the left in the traveling direction). , A reverse lever (forward / reverse switching lever) 18 is provided, and an accelerator lever 38 is provided on the other side (right side).
[0014]
The engine 5 and the transmission case 9 are connected via a power transmission mechanism such as a transmission shaft or a universal joint.
The cabin 12 is placed above the engine frame 21 from the rear to the transmission case 9. A driving unit including a steering handle 13, a seat 14, and the like is installed inside the cabin 12.
As shown in FIG. 2, a steering column 27 is disposed inside the dashboard 16, and a steering shaft 44 connecting the steering handle 13 and a steering mechanism is inserted through the steering column 27.
[0015]
Next, the connection structure of the base of the reversing lever 18 according to the present invention will be described with reference to FIGS.
The base of the reverser lever 18 is attached to and supported by an upper support plate 20 fixed on the steering column 27. The reversing lever 18 is formed in a rod shape, and one end of the reversing lever 18 protrudes downward and to the left of the steering handle 13, and its base is disposed substantially horizontally in the left-right direction. Fixed to. In the present embodiment, the connecting member 22 is formed by bending a plate into a substantially inverted U-shape in a side view, inserted into the upper closing portion side of the connecting member 22, and fixed by welding or a screw. An end of the reversing lever 18 protrudes toward the steering shaft 44, and the end is inserted into a long hole 23 a provided in a guide 23 erected on the upper support plate 20. The long hole 23a forms a concave portion which is recessed upward so as to be held at the neutral position, and the turning range of the reversing lever 18 is limited by the long hole 23a, so that the operator cannot touch and switch back and forth when getting on and off. I have to.
[0016]
The upper end of a reversing shift shaft 24 arranged vertically is pivotally supported by a bolt 25 at the lower portion of the connecting member 22 and is screwed and fixed by a nut 26 via a washer 40. The upper and lower portions of the reversing shift shaft 24 vertically pass through horizontal portions of an upper support plate 20 and a lower support plate 28 which are fixed substantially in parallel with the outer peripheral surface of the steering column 27, via bushes 29, 29. And is supported rotatably and is prevented from falling off by a washer, a collar, and the like and an E-shaped retaining ring 36. Thus, the reversing lever 18 is rotated back and forth about the reversing shift shaft 24.
A base of a plate-shaped rotating arm 30 arranged in a horizontal direction is inserted through and fixed to an upper halfway of the reversing shift shaft 24, and the rotating arm 30 is arranged on the upper support plate 20, It is protected and supported by the original. Thus, the rotation is performed in conjunction with the rotation of the reverser shift shaft 24. A return spring 31 is interposed between the turning arm 30 and the reversing lever 18 to urge the reversing lever 18 to turn downward. Thus, the tip of the reversing lever 18 is urged to fit into the recess, so that the neutral position is maintained.
[0017]
One end of a rotating body 19 having an axial center in the front-rear or left-right direction is connected to a rotating arm 30 fixed to the reversing shift shaft 24, and the rotating body 19 is connected to a forward / reverse clutch via a transmission mechanism. . That is, a connecting pin 32 is vertically inserted into and fixed to the tip of the rotating arm 30 and protrudes downward. The lower end of the connecting pin 32 is slidably inserted in the connecting shaft 33 in a direction perpendicular to the axis thereof.
The connecting shaft 33 is rotatably supported between the rotating body 19 and the upper part of the link plate 35, which are arranged in parallel in the front and rear direction with the axis in the front-rear direction, and connects between the rotating body 19 and the link plate 35. An insertion hole perpendicular to the axis of the shaft 33 is opened in the vertical direction, and the lower part of the connection pin 32 is slidably inserted into the insertion hole.
The rotating body 19 and the lower part of the link plate 35 are fixed to a collar 34, which is pivotally supported by a support shaft 37 via a bush. The support shaft 37 is attached to the lower support plate 28 in the front-rear horizontal direction. It is supported and fixed.
[0018]
The rotating body 19 is formed in a bell crank shape, and has a hole 19b opened in the center portion, and a collar 34 is inserted and fixed to serve as a rotating fulcrum. A hole 19a is opened at the upper end of the rotating body 19 to pivotally support one end of the connecting shaft 33, and the other end of the rotating body 19 is projected toward the left and right center sides of the body, and a hole 19c is formed at the end. It is open and pivotally supports the upper end of the connection link 45 with a pin or the like. The other end of the connection link 45 is connected to a forward / reverse switching clutch provided on the transmission case via a transmission mechanism such as an arm or a link.
[0019]
That is, when the neutral holding is released while the reversing lever 18 is turned upward, and the turning operation is performed forward or backward, the reversing shift shaft 24 is turned via the connecting member 22, and accordingly, the reversing shift is performed. A rotating arm 30 fixedly protruding rearward from the shaft 24 is rotated left or right around the reverser shift shaft 24 as a center axis, and a connecting pin 32 inserted through the rotating arm 30 is moved right and left. While rotating in the axial direction with respect to the connection shaft 33 by interlocking rotation, the rotating body 19 is rotated left or right around the support shaft 37 through the connection shaft 33, By moving the connecting link 45 pivotally supported by the hole 19c upward or downward, the forward / reverse switching clutch is switched to forward or reverse through an arm, a link, or the like.
[0020]
With such a structure, the reverser lever 18 is disposed on the dashboard 16 near the steering handle 13, and the operation transmission mechanism in the dashboard 16 conventionally has a link from the reverser lever 18 to the connection link 45. In the mechanism, the link rod 41 and the link spherical joints 42a and 42b are interposed. However, in the present invention, the link rod 41 and the link spherical joints 42a and 42b are formed by using a link mechanism employing the connection shaft 33. The rotating body 19 can be rotated without using it.
[0021]
Therefore, the link mechanism from the reversing lever 18 to the rotating body 19 can be simplified, so that the number of parts can be reduced and cost can be reduced. Further, the operation direction can be changed in a limited space in the dashboard. Further, the loss and error generated in each link in the transmission process of the link mechanism can be reduced, and the link effect can be improved.
[0022]
【The invention's effect】
The present invention is configured as described above, and has the following effects.
[0023]
That is, as set forth in claim 1, a reverser lever for switching between forward and backward is arranged on a dashboard near a steering handle, and an operation transmission mechanism of the reverser lever is arranged in the dashboard. Is attached to a reverser shift shaft provided in the up-down direction so as to be rotatable in the front-rear direction, a turning arm is fixed to the reverser shift shaft, and the turning arm has a front-rear or left-right axis. Of the reversing lever and the forward / reverse clutch via the transmission mechanism, so that the link mechanism from the reversing lever to the rotating body can be simplified, the number of parts can be reduced, and Cost reduction can be achieved. Further, the operation direction can be changed in a limited space in the dashboard. Furthermore, since the number of links is reduced, the loss that occurs in the process of each link can be reduced, and the link effect can be improved.
[0024]
According to a second aspect of the present invention, a connecting pin protrudes from the rotating arm, and the connecting pin is slidably disposed on a connecting shaft rotatably provided on the rotating body. The effect is obtained, and the use of a dry ash enables high-frequency use, and a long life and easy maintenance.
[Brief description of the drawings]
FIG. 1 is a side view of a tractor provided with a link mechanism of a reverser lever according to the present invention.
FIG. 2 is a front view showing a link mechanism of a reverser lever.
FIG. 3 is a side view of the same.
FIG. 4 is a sectional view taken along line AA of FIG.
FIG. 5 is a front view showing a link mechanism of a conventional reverser lever.
FIG. 6 is a plan view of the same.
[Explanation of symbols]
13 Steering handle 16 Dashboard 18 Reverser lever 19 Rotating body 24 Reverser shift shaft 27 Steering column 30 Rotating arm 33 Connecting shaft

Claims (2)

A reverser for switching between forward and rearward movement is disposed on a dashboard near a steering handle, and an operation transmission mechanism for the reverser lever is disposed in the dashboard. Attached to the shift shaft, it is rotatable in the front-rear direction, a rotating arm is fixed to the reversing shift shaft, and the rotating arm is connected to one end of a rotating body having an axis in the front-rear or left-right direction. A switching mechanism for a forward / reverse switching lever, which is connected to a forward / reverse clutch from a moving body via a transmission mechanism. 2. The forward / reverse switching according to claim 1, wherein a connecting pin protrudes from the rotating arm, and the connecting pin is slidably disposed on a connecting shaft rotatably provided on the rotating body. Lever switching mechanism.

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