JPH04358928A - Speed change operation device for tractor - Google Patents

Abstract

PURPOSE:To enhance the degree of arrangement freedom in an operating lever, provide easy operation, and shut down the vibration of a vehicle body by separating a speed change lever from the operating lever, and converting the oscillation of the operating lever in the front/rear and right/left directions of the operating lever into the axial movement and rotation of the speed change lever through two wires. CONSTITUTION:At plural fork shafts 2 parallel-installed in a transmission case 1, there are provided shift engagement bodies 3. A speed change lever 5 which selectively-engages with the respective shift engagement bodies 3 is supported at a speed change base 4 installed on the transmission case 1. With this constitution, the first selection lever 7 and the speed change lever 5 are engaged with a selection shaft 6 installed on the speed change base 4 so that it may rotate smoothly. The second selection lever 8 which engages with the speed change lever 5 and moves it in an axial direction is pivoted on the speed change base 5. An operating lever 10 is pivoted at a vehicle constitution member 9 above the transmission case 1. Moreover, the operating lever 10 and the respective selection levers 7, 8 are interlockingly-connected with each other through respective wires 11, 12.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tractor speed change operating device in which a plurality of shifters are operated by a single control lever.

0002

[Prior Art] For example, in an agricultural tractor, the main transmission operating device has a five-speed or four-speed transmission, and as shown in FIG. 2 are arranged in parallel, each fork shaft 2 is provided with a shift engaging body 3, the transmission case 1 is provided with a gearbox 4, and each shift engaging body 3 is selectively engaged with this gearbox 4, and the fork shaft A shift lever 5 that is moved in the axial direction is provided, and this shift lever 5 is formed long and serves as an operating lever.

[0003] The speed change lever 5 and operation lever is disposed in front of the driver's seat passing through the floor seat, but its front, rear, left and right positions cannot be far away from the speed change table 4 and are restricted.

0004

[Problems to be Solved by the Invention] In the prior art described above, the gear shift lever 5 is integrated with the operating lever, and its front, rear, left, and right positions are limited, so there is no freedom in selecting the position of the operating lever. , operations may be difficult. In addition, in a tractor with an independently mounted cabin, the cabin is mounted via a mount rubber in order to prevent vibrations from the tractor from propagating to the cabin. The vibration will be propagated to the operating lever, causing an undesirable problem of vibration.

[0005] The present invention separates the speed change lever from the operation lever, and provides the speed change lever on a select shaft rotatably supported on the speed change table so as to be movable in the axial direction and rotatable integrally with the select shaft, so that the speed change lever can be moved forward, backward, left and right of the operation lever. By converting the rocking motion into axial movement and rotation of the gear shift lever via two wires,
It is an object of the present invention to provide a tractor speed change operating device that can solve the problems of the prior art.

[0006]

[Means for Solving the Problems] A specific means for solving the problems in the present invention is to arrange a plurality of fork shafts 2 in parallel in a transmission case 1, and to provide a shift engaging body 3 on each fork shaft 2. , a gear shift operating device for a tractor in which a transmission case 1 is provided with a gearbox 4, and the gearbox 4 supports a gearshift lever 5 that selectively engages with each shift engaging body 3 to move it in the axial direction of the fork shaft. A select shaft 6 is rotatably provided on the speed change table 4, a first select lever 7 for rotation is provided on the select shaft 6, and the speed change lever 5 is fitted so as to be movable in the axial direction and rotatable as a unit. 4
A second select lever 8 is pivotally supported to engage the gear shift lever 5 and move in the axial direction, and an operating lever 10 is pivotally supported to the vehicle component 9 above the transmission case 1 so as to be swingable back and forth and left and right. The operating lever 10 and the first and second select levers 7 and 8 are interlocked and connected via wires 11 and 12.

[0007]

[Operation] In FIG. 1, when the operating lever 10 is swung in the front-rear direction A, the second select lever 8 is connected via the wire 12.
is rotated, the shift lever 5 is moved in the axial direction with respect to the select shaft 6, and the shift engaging body 3 to be engaged is selected. When the operating lever 10 is swung in the left-right direction B with the shift engagement body 3 selected, the first select lever 7 is rotated via the wire 11, thereby rotating the select shaft 6 and the shift lever 5 together. and the engaged shift engaging body 3
is moved together with the fork shaft 2 in the axial direction of the fork shaft.

[0008] The operating lever 10 includes a gear shift lever 5 and a wire 1.
The wires 1 and 12 are interlocked and disposed on the vehicle component 9 regardless of the position of the gear shift lever 5, and vibrations from the transmission case 1 are blocked by the wires 11 and 12.

[0009]

Embodiments Hereinafter, embodiments of the present invention will be explained based on the drawings. In FIG. 5, 15 is a tractor having an independently mounted cabin 16, and a vehicle body 19 is constituted by an engine 17, a clutch housing 18, a transmission case 1, and the like. A hydraulic system 20 and a driver's seat 21 are arranged at the rear upper part of the vehicle body 19. Reference numeral 22 indicates a control handle, and reference numeral 23 indicates a rear wheel fender constituting a part of the cabin 16, and the vehicle component 9 (constituent member of the cabin 16) such as the fender 23 or the floor seat 24 is provided with a gear shift operating device. A lever 10 is arranged.

In FIGS. 1 to 5, a plurality of transmission shafts 25 for transmitting engine power and changing speed are installed in the mission case 1.
, 26 are supported, and the transmission gears, shift gears, etc. that constitute the transmission mechanism are supported by them, and a plurality of shifters 27 for shifting the shift gears of the main transmission mechanism are respectively attached to the fork shaft 2. In the embodiment, three fork shafts 2 are arranged in parallel, and each fork shaft 2 is provided with a shift engaging body 3. The shift engaging body 3 may be molded integrally with the shifter 27 or formed separately. and fork shaft 2
There are some types that are installed at intervals in the axial direction.

A hole 30 is formed in the upper side of the transmission case 1, and a transmission table 4 is provided so as to close this hole 30. A select shaft 6 is rotatably supported on the gearbox 4 along the direction in which the fork shafts 2 are lined up, and a spline is formed in the middle of the gearbox 4, with one end protruding from the gearbox 4 and having an oval cross-section. It is formed. A first select lever 7 for rotating the select shaft 6 is provided at the protruding end portion of the select shaft 6, which has an oval cross section, and a speed change lever 5 is spline-fitted to the midway portion thereof so as to be movable in the axial direction.
The tip of the shift lever 5 can be selectively engaged with the engaging portions 3a of the three shift engaging bodies 3, and a pin or ball 28 provided on the outer shift engaging body 3 and a spring 29
When not operated, the neutral return means is engaged with the center shift engaging body 3.

An engagement recess 31 is formed in the gear shift lever 5, and the second select lever 8 is engaged with this engagement recess 31. The second select lever 8 has lever plates 33 and 34 fixed to both ends of a pivot shaft 32, and the pivot shaft 31 is pivotally supported through the transmission table 4. By rotating this second select lever 8, the shift lever 5 can be moved in the axial direction on the select shaft 6, and the shift engaging body 3 selected by the shift lever 5 can be moved along the fork shaft 2 along with the fork shaft 2. move in the direction.

Wires 11 and 12 are connected at one end to the first select lever 7 and the second select lever 8 via a ball joint or a connecting pin. The wires 11 and 12 are formed of Bowden wires or push-pull wires having an outer wire and an inner wire, and the other ends are connected to the operating lever 10. The lower end of the operating lever 10 is fixed to a rotating body 37, and this rotating body 37 is supported by a pivot body 39 via a first pivot 38.
is supported by a bracket 41 via a second pivot 40, and the bracket 41 is fixed to the vehicle component 9.

Therefore, in FIG. 1, the operating lever 10 and the rotating body 37 can swing back and forth (direction A) about the first pivot 38, and by swinging back and forth, they push and pull the wire 12, and also push and pull the wire 12. It can swing left and right (direction B) about two pivots 40, and by swinging left and right, the wire 11 is pushed and pulled. The transmission table 4 can be directly attached to the conventional transmission case 1 in place of the conventional transmission table 4 shown in FIG. 9, and the transmission operating device can be replaced as a unit.

In addition, in FIGS. 3 and 4, there is a hole 4 in the transmission table 4.
This hole 42 is for penetrating the pivot shaft 32 of the second select lever 8, and changes the directionality of the second select lever 8, that is, the direction in which the wire 12 is pulled. When not in use, it is closed with a stopper. FIG. 6 shows a modification of the neutral return means for the speed change lever 5, which is comprised of two bamboo-shaped coil springs 44 and 45 fitted to the select shaft 6 within the speed change table 4. 46 is a holder that holds the outer ends of each coil spring 44, 45. The two coil springs 44 and 45 do not have the same strength, but the lower spring 45
Since the gravity of the gear shift lever 5 is applied to the lever 5, it is made stronger than the upper side.

Since the neutral return means of this modification is closer to the supporting portion of the gear shift lever 5 than that of the embodiment described above, it can smoothly push the gear shift lever 5 to the neutral position without rattling the gear shift lever 5 with respect to the select shaft 6. can move. Figures 7 and 8
shows a modification of the arrangement structure of the select shaft 6, in which the select shaft 6 is arranged parallel to the fork shaft 2. Therefore, when the wire 11 is pushed or pulled, the select shaft 6 rotates via the first select lever 7, and the shift lever 5 selects the shift engaging body 3. When the wire 12 is pushed or pulled, the second select lever 8 moves the speed change lever 5 in the axial direction of the select shaft 6, and moves the selected shift engaging body 3 and shifter 27.

It should be noted that the present invention is not limited to the embodiments described above, and can be modified in various ways. For example, a structure that supports the operating lever 10 so as to be able to swing back and forth and left and right is such that the wire 11 is attached to a support that can be rotated around the front and rear axes, and a rotating body is provided to this support via the left and right axes. The operating lever 10 may be erected and the wire 12 may be connected to the operating lever 10. Further, it is preferable that a spring for returning the inner wire is provided between the inner wire and the outer wire of the wires 11 and 12.

[0018]

Effects of the Invention According to the present invention described in detail above, the transmission platform 4
A select shaft 6 is rotatably provided on the select shaft 6, a rotatable first select lever 7 is provided on the select shaft 6, and a gear shift lever 5 is fitted so as to be movable in the axial direction and integrally rotatable. 5 to engage with and move in the axial direction.
A select lever 8 is pivotally supported, and an operating lever 10 is pivotably supported on a vehicle component 9 above the transmission case 1 so as to be swingable back and forth and left and right, and this operating lever 10 and the first and second select levers 7 and 8 are connected to each other. Since they are interlocked and connected via wires 11 and 12, the operating lever 10 can be placed anywhere, increasing the degree of freedom in selecting the placement position, making operation easier, and also blocking vibrations from the vehicle body. .

[Brief explanation of drawings]

FIG. 1 is a cross-sectional front view showing an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the main parts.

FIG. 3 is a sectional view taken along the line X--X in FIG. 1;

FIG. 4 is a view taken along the Y arrow in FIG. 1;

FIG. 5 is a side view of the tractor with a cabin.

FIG. 6 is a cross-sectional front view showing a modification of the neutral return means.

FIG. 7 is an exploded perspective view showing a modification of the arrangement structure of the select shaft.

FIG. 8 is a perspective view of the transmission table seen from outside.

FIG. 9 is a cross-sectional front view showing a prior art.

[Explanation of symbols]

1 Mission case 2 Fork shaft 3 Shift engaging body 4 Gearbox 5　Shift lever 6 Select axis 7 First select lever 8 Second select lever 9 Vehicle component parts 10 Operation lever 11 Wire 12 Wire

Claims (1)

[Claims] [Claim 1] A plurality of fork shafts (2) are arranged in parallel in a mission case (1), and each fork shaft (2)
A shift engagement body (3) is provided in the transmission case (1).
A gearbox (4) is provided at the gearbox (4), and the gearbox (4) supports a gearshift lever (5) that selectively engages with each shift engagement body (3) and moves it in the axial direction of the fork shaft. In the operating device, a select shaft (6) is rotatably provided on the speed change table (4), a first select lever (7) for rotation is provided on the select shaft (6), and the speed change lever (5) is moved in the axial direction. Fits freely and rotates as a unit, allowing the gearbox (
A second select lever (8) that engages with the gear shift lever (5) and moves in the axial direction is pivotally supported on the transmission case (1), and a control lever (10) is attached to the vehicle component (9) above the transmission case (1).
) is pivoted so that it can swing back and forth, left and right, and this operating lever (10
) and the first and second select levers (7) and (8) are interlocked and connected via wires (11) and (12).