JPH02267027A - Transmission device of tractor - Google Patents

Abstract

PURPOSE:To lower the center of gravity by installing a steering shaft on the top of a transmission case, and disposing a traveling input shaft and a traveling transmission shaft of a traveling transmission device over the lower periphery of the steering shaft, the power intake input shaft and a power intake transmission shaft of a power intake transmission device respectively at the lower part. CONSTITUTION:A transmission device in a transmission case 2 is provided with a traveling transmission device 7 which travels by transmitting wheels and a power intake transmission device 9 which works by transmitting a working device mounted on a vehicle body and so on. The device 7 is driven by inputted power into a traveling input shaft 8 to transmit rear wheels, front wheels 4 and so on through a transmission gear installed on traveling transmission shafts 16, 17 and so forth. Power is inputted into a power intake shaft 10 to give transmission from the power intake shaft to the working device through the transmission gear and so on installed on a power transmission shaft 18. A steering shaft 6 rotated by a steering handle 3 is installed on the top of the case 2, and through the steering shaft 6 the front wheels 4 or rear wheels of the steering wheel are steered interlockingly.

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a tractor transmission device, and relates to related structures such as a traveling transmission device that transmits power to wheels and a power take-off transmission device that transmits power to a working device connected to a vehicle body. It is something.

Background Art and Problems to be Solved by the Invention In a four-wheeled tractor that has a front axle at the front of the vehicle body and a rear axle at the rear, the transmission case is likely to be located at the bottom of the vehicle body. Therefore, when the transmission mechanism inside the transmission case is lowered, the ground clearance of the bottom of the transmission case tends to increase.

Means for Solving the Problems This invention provides a steering wheel which is interlocked to steer the steering axles (4) and (5) by operating the steering handle (3) on the upper part of the transmission case (2). A shaft (6) is provided, and a traveling transmission device (7) is provided at the bottom of the steering shaft (6).
traveling input shaft (8) and traveling transmission shaft (16) (17)
), a moving input shaft (lO) of a power take-off transmission (9), and a moving power take-off transmission shaft (18).

Functions and Effects of the Invention The transmission device in the transmission case (2) has a travel transmission device (7) that transmits power to the axle and travels, and a power take-off transmission device that transmits the work device attached to the vehicle body for work. (9)
etc. This traveling transmission device (7) has a traveling input shaft (
8), and drive the traveling transmission shaft (16) (17
), etc., to drive the rear axle (5), front wheels (4), etc., through a transmission gear, etc., to drive the vehicle. In addition, the moving input shaft (10
), the power is transmitted to the working device from the power output shaft via a transmission gear etc. provided on the power output transmission shaft (18).

The vehicle body is steered by operating the steering handle (3), and the steering shaft (3) is rotated by the steering handle (3).
6) is provided on the upper part of the transmission case (2), and the steering axle (4) or (5) is interlocked in steering via this steering shaft (6). This steering axle (4) (5) is the front axle (4)
Front wheel steering only, or both front and rear axles (4) (5
), but the latter mode is used for rotation.

In this way, the steering shaft (
6) as the center, and the traveling input shaft (8) of the traveling transmission device (7) and the traveling transmission shaft (16) over the lower peripheral part.
(17) etc., as well as a power take-off transmission device (9)
Since the drive input shaft (10), drive transmission shaft (18), etc. are provided, the structure of the transmission case (2) can be made vertically thinner, and the steering shaft (6) can also be made thinner. Since it is installed internally, there is no high tension between the top and bottom, and the center of gravity can be lowered.
This is effective for vehicle body configurations in which the front axle is installed near the top of the front axle.

Embodiment In addition, in the rotation, the front part of the tractor body (19) has a front shaft (
21) and a front axle case (22), and a steerable front axle (4) is mounted on both left and right ends of the axle case (22). or,
A rear wheel axle (23) and a rear axle case (24) are provided at the rear, and steerable rear wheels (5) are mounted on both left and right ends of the rear wheel axle (23) and a rear axle case (24). These front axle (4) and rear axle (5) have a four-wheel drive configuration in which power is transmitted by an engine (1) mounted at the front of the vehicle body (19).

The engine (1) is mounted on the upper part of the front axle case (22) at the front of the vehicle body (19), and the transmission case (2) is located behind the engine (1). (25) is a front axle bracket, which connects the engine (1) to the front end surface of the vehicle body and is integrally attached to the front lower part of the engine (1).
The front axle case (22) is supported by a center pivot (20).

The engine (1) is provided with a drive shaft (11), which is an extension of the crankshaft, in the center of the front side in the left and right direction.
The belt (12) transmits power between the upper pulley (26) and the pulley (27) at the front end of the running input shaft (8), and also between the pulley (28) at the front end of the moving input shaft (10). Belt between (
13) Transmission. (29) is a clutch pulley that turns on and off the transmission of the belt (12), and is configured to be able to switch to two-speed transmission. (30) is a clutch pulley that turns on/off transmission of the belt (13).

The transmission case (2) has a travel transmission device (7) and a power take-off transmission device (9) at the bottom, and a steering handle (3) at the top.
Steering transmission shaft (31) (32) interlocked with
, and the steering shaft (6), etc., are installed in this transmission case (2).
The bottom surface of the front wheel axle case (22) is set near the top of the gate-shaped front wheel axle case (22). The steering power transmission shaft (31), which is rotated through the lower end of the handle shaft (33) of the steering handle (3) and the bevel gear (34), has a gear (35) in the center in the front-rear direction.
A steering transmission shaft (32) parallel to the steering transmission shaft (31) is provided with gears (36) (37) at the front and rear thereof,
These gears (35) and (36) are always meshed to connect each steering transmission shaft (31) (32) to the handle shaft (33).
) to rotate in opposite directions. Further, below both of the transmission shafts (31) (32), longitudinal switching shafts (38) (39) made of spline shafts supported in parallel with these transmission shafts (38) (39) are provided so as to be freely rotatable on the same axis. Fan-shaped front and rear switching gears (40, 41) are spline-fitted to each shaft (3g) (39) and are simultaneously moved in the axial direction by a switching shifter (14) to perform switching operations. These front and rear switching gears (40) (41) have lock pins (42).
(43) are provided, and are fitted into lock holes (44) and (45) provided in the front and rear walls of the transmission case (2) to fix the front and rear switching gears (40) and (41) so that they cannot rotate. be able to.

The position where these lock pins (42) and lock holes (44) can fit together, or between (43) and (45), is at the neutral position where the steering handle (3) travels straight; The lock pins (42) (43) are attached to the transmission case (2) so that they cannot be engaged at steering angles other than the position.
) and is restrained by contacting the inner wall surface of the

By operating the switching lever (46) on the control device, the switching shifter (14) is activated, and the front and rear switching gears (40) (41)
When the front switching gear (40) is moved to the rear end side, the front switching gear (40) changes to the gear (
36), the rear switching gear (41) is in mesh with the gear (
37), and the lock pin (43) is inserted into the lock hole (4).
5), and only the front switching shaft (38) can be interlocked with the steering by the steering handle (3). When the switching shifter (4) is moved to the center position, the front switching gear (40) meshes with the gear (36), and the rear switching gear (41) meshes with the gear (37), allowing for longitudinal axis operation. (W), and the front switching shaft (38) and the rear switching shaft (39) are steered in the same direction. Also, set the switching shifter (14) to the front end position and set the front switching gear (40
) from the gear (36), fit the lock pin (42) into the lock hole (44), and at the same time remove the rear switching gear (41).
is disengaged from the gear (37) and meshes with the gear (35), resulting in the rear shaft steering (R) mode, and only the rear switching shaft (39)
The steering handle (3) compared to the case of longitudinal axis steering (W)
The steering is linked in the opposite direction to the steering direction.

The front switching shaft (38) passes through the steering linkage (47),
It is connected to the arms of the left and right front wheel cases (48) and is configured to steer and rotate left and right. In addition, the rear switching shaft (39) is connected to the left and right rear shaft cases (5) via the steering link mechanism (49).
0) is configured to rotate for steering.

The relationship between these steering link mechanisms (47) and (49) is as follows:
In the above-mentioned longitudinal axis steering (W), the front and rear axles (4) and (5) are provided so as to be steered and rotated in the same direction.

The travel transmission device (7) has a travel input shaft (8) mounted parallel to the -side of the steering shaft (6).
(16) (17)
The driving transmission shaft (17) is located directly below the steering shaft (6). Further, a back counter shaft (51) is provided between the travel input shaft (8) and the travel transmission shaft (16). These travel input shafts (8) and travel transmission shafts (16)
) and the back force outer shaft (51), there are provided a forward/reverse switching gear (52), counter gear (53), back gear (54), etc. A transmission gear (55) that is engaged with the counter gear (53) is provided, and is operated by a shifter mechanism that changes speed and is operated by /<- (56). By inputting and rotating the traveling input shaft (8), the traveling transmission shaft (17) can perform variable speed transmission.

The front end of the traveling power transmission shaft (17) is connected to the front shaft case (2).
2) The left and right front axles (21) are differentially transmitted via the differential transmission Fj (57) in the center, and the rear end is connected to the differential transmission (58) in the center of the rear axle case (24). ) is configured to differentially transmit the left and right rear axles (23).

In the power take-off transmission device (9), a moving plate input shaft (10) is provided on the opposite side of the steering shaft (6) to the traveling input shaft (8), and the moving plate input shaft (10) runs on the moving input shaft (18). A transmission gear (59) is provided between the transmission shaft (17) and the transmission plate input shaft (10).
) and the gear (60) on the transmission shaft (18), transmission can be performed at variable speeds. This drive transmission shaft (18
) is decelerated by a reduction gear (61) in the rear axle case (24), protrudes from the rear end of the vehicle body (19) as a power take-off shaft (62), and transmits the working device (63). It is.

A driver's seat (64) is provided at the rear of the vehicle body (19), and a lift arm (66) that is moved up and down by a hydraulic system (65) is provided below the driver's seat (64). A working device (63) connected to the side by an arm (67) so as to be able to move up and down is controlled up and down by the lift 1 to the arm (66). The working device (63) has a power take-off shaft (6
2) is a tillage and weeding management device equipped with a tilling shaft (68) that is transmitted from the tilling shaft (68), and which tills the soil surface with the tilling shaft arranged along this tilling shaft (68).(69) is a tiller. be.

[Brief explanation of drawings]

The figures show one embodiment of the present invention; FIG. 1 is a partial front sectional view, FIGS. 2 and 3 are side sectional views, FIG. 4 is a partial front view, and FIG. 5 is a partial front sectional view. 6 is a plan view showing a part of the transmission mechanism, FIG. 6 is a side view, FIG. 7 is a plan view, and FIG. 8 is a front view. In the figure, code (1) is the engine, (2) is the transmission case, (
3) is the steering handle, (4) is the front axle, (5) is the rear wheel, (6) is the steering shaft, (7) is the travel transmission, (8) is the travel input shaft, (9) is the power Take-out transmission device, (10) is the moving input shaft, (11) is the drive shaft, (12) (13) is the belt, (14) is the switching shifter, (15) is the neutral display device, (16) (17) (18) indicates the traveling transmission shaft, and (18) indicates the moving transmission shaft.

Claims (1)

[Claims] The upper part of the transmission case (2) is provided with a steering shaft (6) that is interlocked to steer the steering axles (4) and (5) by operating the steering handle (3), and the lower part thereof is This steering axis (6
), the traveling input shaft (8) and traveling transmission shafts (16, 17) of the traveling transmission device (7), and the moving input shaft (10) and the traveling transmission shaft (10) of the power take-off transmission device (9). Drive transmission shaft (1
8) A tractor transmission device comprising: