JPH04357368A - Tractor speed control device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

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 operating 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 gear shift lever and the operating lever, and fixes the gear shift lever to a select shaft rotatably and axially movably supported on the gearbox, thereby controlling the front, rear, left, and right rocking of the operating lever. An object of the present invention is to provide a tractor speed change operation device that can solve the problems of the prior art by converting the rotation and axial movement of a select shaft and a speed change lever via two wires. shall be.

[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 and freely movable in the axial direction on the speed change table 4, a speed change lever 5 is fixed to the select shaft 6, and a rotary select lever 7 is provided, and a vehicle component above the transmission case 1 is provided. A control lever 10 is pivotally supported on the control lever 9 so as to be swingable back and forth and left and right, and these and the control lever 10 are interlocked via wires 11 and 12 in order to rotate the select lever 7 and move the select shaft 6 in the axial direction. It means that they are connected.

[0007]

[Operation] In FIG. 1, when the operating lever 10 is swung in the longitudinal direction A, the select shaft 6 is moved in the axial direction via the wire 12, and the gear shift lever 5 is moved together with the select shaft 6. 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 select lever 7 is rotated via the wire 11, and thereby the select shaft 6 and the gear shift lever 5 are rotated together. 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 and axially movably supported along the direction in which the fork shafts 2 are lined up on the gearbox 4, with one end protruding from the gearbox 4 and formed into an oval shape in cross section. . A select lever 7 for rotating the select shaft 6 is provided on the protruding end 6a having an oval cross-section, and a shift lever 5 is fixed in the middle with a through pin or welding. The tip of 5 can be selectively engaged with the engaging portions 3a of the three shift engaging bodies 3, and the neutral return mechanism has a pin or ball 28 and a spring 29 provided on the outer shift engaging body 3. When not in operation, the shift engaging body 3 is engaged with the central shift engaging body 3.

Wires 11 and 12 are connected at one end to the select lever 7 and the protruding end 6a of the select shaft 6 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. Operation lever 10
is fixed at its lower end to a rotating body 37, and this rotating body 37 is connected to the first
It is supported by a pivot body 39 via a pivot shaft 38, and this pivot body 3
9 is supported by a bracket 41 via a second pivot 40,
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. When the wire 12 is pushed or pulled, it moves the select shaft 6 in the axial direction, and selects the shift engagement body 3 with which the speed change lever 5 is engaged. Also,
When the wire 11 is pushed or pulled, it rotates the select shaft 6 via the select lever 7, and the shift lever 5
The selected shift engaging body 3 is moved together with the fork shaft 2 in the axial direction of the fork shaft.

It should be noted that even if the select lever 7 moves slightly in the axial direction of the select shaft 6, there will be no problem with the gear change operation. A circumferential groove may be formed in the boss portion of 7, and an engagement piece that engages with this circumferential groove may be provided on the gearbox 4 to restrict the position of the select lever 7 so that it does not move in the axial direction. .

The transmission stand 4 can be directly attached to the conventional transmission case 1 in place of the conventional transmission stand 4 shown in FIG. 8, and the speed change operating device can be replaced as a unit. 6 and 7 show 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 select lever 7, and the shift engagement body 3 with which the speed change lever 5 engages is selected. Then, when the wire 12 is pushed and pulled, the select shaft 6
moves in the axial direction, and moves the selected shift engaging body 3 and shifter 27 in the axial direction of the fork shaft.

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. The wire 12 is attached to the protruding end 6a of the select shaft 6.
However, it is also possible to pivot a bell crank to the transmission 4, connect the wire 12 to one end of the bell crank, and connect the other end to the protruding end 6a through an elongated hole and a pin. . Further, the neutral return means for the shift lever 5 may be constructed by fitting two bamboo-shaped coil springs to the select shaft 6 so as to sandwich the shift lever 5 therebetween. Furthermore, wire 1
It is preferable that springs 1 and 12 for returning the inner wire are provided between the inner wire and the outer wire.

[0017]

Effects of the Invention According to the present invention described in detail above, the transmission platform 4
A select shaft 6 is provided rotatably and freely movable in the axial direction, a gear shift lever 5 is fixed to the select shaft 6, and a rotating select lever 7 is provided. 10 is pivotally supported so as to be able to swing back and forth, left and right, and the select lever 7 is rotated and the select shaft 6 is moved in the axial direction.
0 through 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 reducing vibrations from the vehicle body. can also be blocked.

[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 an exploded perspective view showing a modification of the arrangement structure of the select shaft.

FIG. 7 is a perspective view of the transmission table seen from outside.

FIG. 8 is a cross-sectional front view showing the prior art.

[Explanation of symbols]

1 Mission case 2 Fork shaft 3 Shift engaging body 4 Gearbox 5　Shift lever 6 Select axis 7 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 and freely movable in the axial direction provided on the speed change table (4), a speed change lever (5) is fixed to the select shaft (6), and a rotating select lever ( 7), an operating lever (10) is pivotally supported on a vehicle component (9) above the transmission case (1) so as to be able to swing back and forth, left and right, and the select lever (7) is rotated and a select shaft ( 6) and an operating lever (10) are interlocked and connected via wires (11) and (12) in order to move them in the axial direction.