JPH02208132A - Transmission structure for working vehicle traveling - Google Patents

Abstract

PURPOSE:To increase the space for the working equipment between front and rear wheels, in a working vehicle whose body is provided with a wheel supporting member through a leaf spring for buffering, by arranging a differential mechanism input shaft upwards, and installing a motive power side rotating member on the input shaft through a rotation transmission shaft which can slide vertically. CONSTITUTION:A differential mechanism 18 for rear wheel is disposed at the center case portion 14a of a wheel supporting member 14, facing its input shaft 19 upwards. A belt pulley 24 which transmits power to the space to the downward output shaft of an engine (not shown here) through a transmission belt is positioned on an input shaft 19 and is installed on a vehicle body 17 with a bearing 25 and a pulley supporter 26 so that it may rotate around the shaft center in the vertical direction of a vehicle. Moreover, the input shaft 19 and the belt pulley 24 are connected to a rotation transmission shaft 32 through universal couplings 28, 29 so that it can slide vertically. It is thus possible to increase the space for working equipment between front and rear wheels.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for attaching a wheel support member that supports left and right wheels and has a differential mechanism that transmits power to the left and right wheels to a vehicle body via a buffer leaf spring. This invention relates to a drive transmission structure for a working vehicle.

[Conventional technology]

In the above-mentioned work vehicle, conventionally, the input shaft of the differential mechanism is mounted in the longitudinal direction of the vehicle body, and the rotary shaft that transmits engine output to this input shaft is provided with an extendable portion and a bending portion. Vertical movement of the input shaft relative to the vehicle body is made possible by bending the rotary shaft, and longitudinal movement of the input shaft relative to the vehicle body caused by deformation of the buffer leaf spring as the left and right wheels rise and fall relative to the vehicle body is made possible by expansion and contraction of the rotary shaft. I was supposed to.

[Problem to be solved by the invention]

Conventionally, when increasing the vertical stroke of the left and right wheels relative to the vehicle body in order to improve the steering performance, the vertical stroke of the input shaft of the differential mechanism relative to the vehicle body also becomes large, and the bendable angle of the rotary shaft requires a bending part structure. Since there are limits due to the If this rotating shaft is located between the front and rear wheels of the vehicle body, it is necessary to secure a relatively wide space vertically to allow the rotating shaft to move up and down, so the working equipment may interfere with the rotating shaft. As a result, the front and rear wheels tend to be unable to be connected, or even if they can be connected, the working device cannot be adjusted up and down.

An object of the present invention is to make it possible to increase the vertical stroke of the wheels relative to the vehicle body while maximizing the space for the working device between the front and rear wheels even when a driving transmission means is disposed between the front and rear wheels. It is in.

[Means to solve the problem]

In order to achieve the object, the present invention, in the transmission structure for traveling of a working vehicle described at the beginning, has an input shaft of a differential mechanism mounted upwards on the vehicle body, and a driving side rotating member linked to an engine connected to the input shaft. The lower end side of a rotary power transmission shaft is located above and is attached to the vehicle body so as to be rotatable around the vertical axis of the vehicle body, and the upper end side is interlockingly connected to the driving side rotating member so as to be vertically slidable. The characteristic structure is that the shaft is interlocked with a universal joint.

The functions and effects thereof are as follows.

[For production]

When the left and right wheels move up and down relative to the vehicle body, the movement is transmitted to the rotation transmission shaft via the wheel support member, input shaft, and universal joint.
When the rotating transmission shaft slides upward relative to the driving side rotating member,
When it slides downward and the left and right wheels move back and forth relative to the vehicle body,
The operation is transmitted to the universal joint via the wheel support member and the input shaft, the universal joint bends, and the rotation transmission shaft and the input shaft relatively swing. In other words, power is transmitted while allowing the wheels to move up and down by sliding the rotary transmission shaft, and by allowing the wheels to move back and forth by bending the universal joint. Furthermore, when the wheels are mounted so that they can be raised and lowered using leaf springs, even if the lifting stroke is increased, the forward and backward movement stroke associated with the lifting and lowering can be kept from becoming too large, and the sliding displacement of the rotary transmission shaft can be prevented. Since the permissible displacement can be made larger than the rocking displacement, even if the lifting stroke of the wheel relative to the vehicle body is relatively large, the means for transmitting the engine output to the driving side rotating member can be placed between the front and rear wheels. In this case, even if the transmission means is fixed so that it does not rise or fall regardless of whether the wheels are raised or lowered, power can be transmitted to the left and right wheels as desired regardless of whether they are raised or lowered or moved back and forth.

〔Effect of the invention〕

The transmission system flexibility that allows the wheels to move back and forth is bending flexibility, and the transmission system flexibility that allows the wheels to move up and down is sliding flexibility, so the vertical stroke of the wheels is relatively large. It has become possible to provide excellent cushioning so that the wheels do not easily reach the upper or lower limits even when the road is highly undulating and the shock absorbing leaf springs are made relatively soft. Moreover, even when a power transmission belt or a power transmission rotation shaft for the driving side rotating member is installed between the front and rear wheels, the power transmission means must be fixed so that it will not be displaced regardless of whether the wheels are raised or lowered. It has become possible to make the space relatively large, making it easier to connect the working equipment, and to be able to adjust the lifting and lowering of the working equipment over a large stroke.

〔Example〕

Next, examples will be shown.

As shown in Fig. 3, an engine (E) is installed in the front part, and
Front wheels (2) of a vehicle body each with a driver seat (1) at the rear
A lawn mower (5) is connected between the rear wheels (3) via a link mechanism (4) and can be freely raised and lowered, and the output of the engine (E) is connected to the lawn mower via a transmission belt (6). A riding lawn mower is configured to transmit the information to the device (5).

The left and right front wheels (2), (2) are arranged such that the front wheel (2) is supported via the axle (8) at the boss portion (7a) on the tip side, as shown in FIG. , a wheel support arm (7) configured such that the axle (8) swings around the axis (X) to enable steering swing of the front wheel (2);
It is attached to the vehicle main frame (10) via the attachment member (9). Left and right wheel support arms (7), (7
) are individually pivoted to the mounting member (9) so as to swing up and down around the axis (P, ) or (P), and the spring bearing of one wheel support arm (7) is One end of the shock absorbing coil spring (11) acts on part (7a), and the other end of the coil spring (11) acts on part (7a) of the spring receiver of the other wheel support arm (7). One wheel support arm (7) has a spring support part (7a).
The lowering limit is set by contact with the stopper (12) attached to the mounting member (9), and the spring receiver on the other wheel support arm (7) is connected to the part (7a) of the vehicle body on the - side. The lowering limit is set by contact with the main frame (10).

In other words, the left and right front wheels (2), (2) are configured to move up and down independently relative to the vehicle body, and the running shock acting on the left and right front wheels (2), (2) is alleviated by the same coil spring (11). It is structured as follows.

To install the left and right rear wheels (3), (3), as shown in Figures 1 and 2, install the left and right rear wheels (3), (3).
One wheel support member (14) is attached to each side end via an axle (13) separately, and a round pipe made of It is attached to the vehicle body frame (17). That is, the leaf spring (15) is used to reduce the running shock acting on the left and right rear wheels (3), (3), and the swing link (
16) allows the wheel support member (14) to move back and forth with respect to the vehicle body frame (17),
It is configured to allow elastic deformation of the leaf spring (15) as the left and right rear wheels (3) move up and down.

As shown in FIG. 1, a rear wheel differential mechanism (18) is installed inside the center case portion (14a) of the wheel support member (14), and the input shaft (19) of this differential mechanism (18)
The first transmission belt (21), the transmission (22), and the second transmission belt are attached to the downward output shaft (20) of the engine (E) as shown in Fig. 1.
The belt pulley (24), which is interlocked so that power is transmitted through the bearing (23), is rotated around the vertical axis of the vehicle body at a location located above the input shaft (19). ) and a pulley support member (26) to the vehicle body frame (17), and a ball-based constant velocity universal joint (27) is attached to the belt pulley (24) so that the upper end side is interlocked so that the belt pulley (24) can be moved at rest. Connected rotating transmission shaft (2
8) The lower end side is interlocked with the upper end side of the input shaft (19) by a constant velocity universal joint (29) using a ball so as to be integrally rotatable. The rotation transmission shaft (28) is slidably splined to the transmission shaft side component (27a) of the automatic joint (27), so that the rotation transmission shaft (28) can be attached to the belt pulley (24).
It is constructed so that it can slide up and down.

In other words, the rotational output of the engine (E) is transferred to the transmission (22).
The speed is changed steplessly, and the transmission is transmitted to the belt pulley (24) by switching between forward and reverse directions, and the left and right rear wheels (3), ( While enabling the vertical movement of the input shaft (19) in conjunction with the vertical movement of the input shaft (19) with respect to the vehicle body frame (17) in 3),
In addition, the rotation transmission shaft (28) swings relative to the belt pulley (24) by the universal joint (27), and the universal joint (29)
The relative rocking of the rotational transmission shaft (28) and the input shaft (19) due to the movement of the belt pulley ( 24) is transferred to the input shaft (
19), and transmits the rotational force of the input shaft (19) to the differential gear (
18) to the rear wheels (3) via the axle (13), so that the left and right rear wheels (3), (3
) can be driven.

The brake disc (30) attached to the input shaft (19) so as to be integrally rotatable and slidable is attached to the center case part (14a).
A friction brake (B) configured to press against and release the fixed plate (31) attached to the center case part (14a) is installed inside the center case part (14a).

That is, the vehicle is configured to stop running by applying frictional braking to the left and right rear wheels (3), (3) via the differential mechanism (18) and the axle (13).

Furthermore, the bellows cover (32) shown in Fig. 1 has a universal joint (27).
) and the rotating transmission shaft (28) for dust prevention, and the cap (33) covers the part where the rotation transmission shaft (28) projects upward from the universal joint (27) for dust prevention. .

[Another example]

Belt pulley (24) to enable rear wheel drive
may be implemented by replacing them with chain sprockets, transmission output members, etc. Therefore, these may be replaced with drive side rotating members (
24).

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the power transmission structure for driving a working vehicle according to the present invention, in which FIG. 1 is a partially cutaway rear view of the rear wheel mounting portion, and FIG. 2 is a partially cutaway front view of the front wheel mounting portion. , FIG. 3 is a partially cutaway side view of the entire lawn mower. (3)...Wheel, (14)...Wheel support member, (15)...Buffer leaf spring, (17)
・・・・・・Vehicle body, (18)・・・Differential mechanism, (
19)...Input shaft, (24)--Drive side rotating member, (28)--Rotation transmission shaft, (29)
)... Universal joint, (E)... Engine.

Claims (1)

[Claims] A wheel support member (14) having a differential mechanism (18) that supports the left and right wheels (3), (3) and transmits power to the left and right wheels (3), (3) is attached to a buffer leaf spring (15). A driving transmission structure for a working vehicle, which is attached to the vehicle body (17) through the drive side, in which the input shaft (19) of the differential mechanism (18) is attached upward to the vehicle body, and is linked to the engine (E). The rotating member (24) is positioned above the input shaft (19) to freely rotate around the vertical axis of the vehicle body (17).
a rotational power transmission shaft (28) which is attached to the driving side rotating member (24) and whose upper end side is interlocked and slidably vertically connected to the driving side rotating member (24);
A power transmission structure for driving a working vehicle, in which the lower end side of the input shaft (19) is interlocked with the input shaft (19) through a universal joint (29).