JPH03529A - Tractor travel transmission device - Google Patents

Abstract

PURPOSE:To facilitate turning as well as to concurrently enable a four wheel drive condition to be maintained at all times by providing a control mechanism which controls an automatic switch-over means automatically engaging/disengaging power transmission to a front wheel power transmission shaft based on the running speed of rear wheels, to be in an engaged condition. CONSTITUTION:Power is transmitted to a driven body 37 from the trailing end power transmission shaft 29 of a charge gear mechanism via the spline shaft 30 of an outer package, the sliding cam 39 of a drive body 41, the sliding cam 39 of a slider 40 and both of clutch pawls 36, and is transmitted to a front wheel input shaft via a driven shaft 35. When the braking operation of one side rear wheel forces the ground running speed of the other side rear wheel to be doubled at the time of turning a tractor, front wheels are pushed so as to be advanced, this thereby permits a gap to be made between the driven surface of the sliding cam 39 of the slider 40 and the drive surface of the sliding cam 39 of the drive body 41, and the clutch pawl 36 of the slider 40 comes off from the clutch pawl 36 of the driven body 37 with the slider 40 slid so that the front wheels are conditioned to no power transmission. When an arm 51 is locked at an afterward rotating position, the slider 40 can not be slid in a state that both of the clutch pawls 36 are meshed with each other, a four wheel drive condition can thereby be maintained at all times.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a traveling transmission device for a tractor.

BACKGROUND ART AND PROBLEMS TO BE SOLVED BY THE INVENTION In a so-called four-wheel drive tractor, when braking the negative rear wheel to make a sharp turn, the ground running speed of the other rear wheel is Due to the action of the differential mechanism, the speed is almost doubled, but since the front wheels are also being driven and cannot follow the speed of the rear wheels, this front wheel resistance causes the turning radius to become larger than when the front wheels are not driven. Even if the tractor has a speed increasing mechanism that can increase the speed of the vehicle, or a switching mechanism that can stop driving the front wheels, it is time-consuming to switch these mechanisms at the start of a turn and after the turn. In short,
And it's not easy.

Means for Solving the Problems This invention provides a pair of left and right front and rear wheels (1) (1) (2)
) (2) Located between these front and rear wheels (1) (1)
(2) On the front side of the transmission case (4) in which the transmission mechanism (3) of +2) is installed, the transmission is transmitted from the transmission mechanism (3) and is located between the left and right front wheels (1) (1). In a tractor traveling transmission device that is provided with a front wheel transmission shaft (6) in the longitudinal direction that transmits power to a front wheel differential mechanism (5), there is a When the ground running speed of the rear wheels 12) (2) exceeds a certain range, whether the ground running speed of the front wheels T11ll is forward or backward, the front wheel transmission shaft (6)
The transmission to the rear wheel (2) is automatically set to the inward side, and the rear wheel (2)
An automatic switching mechanism (7) is provided which automatically switches the transmission to the front wheel transmission shaft (6) to the input side when the ground running speed of (2) falls below a certain range. The tractor traveling transmission device is characterized in that a regulating mechanism (8) for regulating the automatic switching mechanism (7) to the entry state by an operating means is provided at the front part.

Effect of the Invention The speed change transmission mechanism (3) in the speed change transmission case (4) transmits power to the left and right rear wheels +2) +2), and also has an automatic switching mechanism (7).

The power is transmitted to the left and right front wheels (1) via the front wheel transmission shaft (6) and the front wheel differential mechanism (5).

For example, when braking the negative rear wheel (2) to make a sharp turn,
When the ground running speed of the other rear wheel (2) becomes approximately twice as fast due to the action of the rear wheel differential mechanism, the automatic switching mechanism (7) automatically cuts off the power transmission to the front wheel transmission shaft (6). Since the front wheels (1) (1) are not driven and the rear wheels T2) +2) are in a two-wheel drive state, the turning radius is smaller than in the case of four-wheel drive. After turning, when the ground speed of the rear wheels (2) 12) returns to normal speed, the automatic switching mechanism (7)
The front wheel transmission shaft (6) is automatically transmitted, resulting in a four-wheel drive state.

In addition, by operating the regulating mechanism (8) to regulate the automatic switching mechanism (7) to the entry state, the four-wheel drive state is maintained, and by releasing the regulation by the regulating mechanism (8), The automatic switching mechanism (7) operates as described above.

Effects of the Invention Due to this effect, there is no need to switch between four-wheel drive and two-wheel drive when turning again, as in the problem described above.
Since it is automatically switched by the automatic switching mechanism (7), turning is therefore facilitated.

In addition, depending on the type of installation work equipment, for example, in cases where so-called dashing of the aircraft occurs, or in the case of climbing, etc., the regulation mechanism (8) can forcefully maintain the four-wheel drive state at all times. Therefore, stable running conditions can be maintained.

Embodiment In addition, when the vehicle is rotated, the frame α forming the front part of the vehicle body
A prime mover 025 having an output shaft 025 protruding rearward is mounted on υ, and this prime mover (13) and the frame (l
At the rear end of θ, there is a clutch α4 transmitted from the output axle load, and a transmission mechanism (transmitted from this clutch α4).
The rear end of this front transmission case (LE) is connected to a front transmission case OI9 which has a transmission mechanism 051 inside. ), and then this transmission case (4)
The rear end part is connected to the rear transmission case (old) which houses the rear wheel differential mechanism ((7)) which is transmitted from the speed change transmission mechanism (3), and the upper side of this rear transmission case Oe is , a pair of left and right lift arms (Fj TF
These lift arms (n) are equipped with a cylinder case holder containing a hydraulic cylinder that transmits power to the lift arm (I).

On the underside of the frame Oo, there is a bin I2)) in the front and back direction.
A support body (2) is provided, and a pin (2+1) of this support body (2) has a front import force shaft (2) that protrudes toward the rear.
A shaft case (c) which has a front wheel differential mechanism (5) that transmits power to this input shaft (2), and a pair of left and right transmission shafts (24124) that transmits power to this differential mechanism (5). is supported swingably, and on both left and right ends of this shaft case 4,
Steering transmission mechanism (a) Front wheel (1) interposed in Ce (1)
), respectively.

On both left and right sides of the rear transmission case OEI, there are rear wheels (2) (2) interposed in transmission cases (2) (3) inside the transmission mechanism, which transmit the power to the rear wheel differential mechanism (5). Provide each.

The front end of the terminal transmission shaft of the transmission mechanism (3) is supported on the bearing (end) provided at the lower part of the front wall of the speed change transmission case (4), and the front end of the transmission shaft (end) is supported. consists of a cylindrical part 01) having a spline O1 on the front part of the inner peripheral surface, a wall part (end) at the rear end of this cylindrical part 0υ, and a boss part 03 protruding rearward from this wall part (support). The automatic switching mechanism (7) is spline connected to the boss portion of the exterior body.

The axial bearing part (b) provided at the front end of the transmission shaft (to) supports the small diameter part of the rear end of the driven shaft (to), and the rear part on this driven shaft (to) In this case, the boss part of the driven body (B) having radially ladder-shaped clutch pawls (to), (to), etc. is spline-coupled to the front surface of the flange-like part, and the corresponding part on the front side of the driven body (B) A bearing (to) that can slide and rotate freely with respect to the driven shaft aS is provided on the driven shaft (to), and the clutch pawl C319 is attached to the rear surface of the flange-shaped portion on the outer peripheral surface of this bearing (to). (To) The clutch pawl that engages with (To) (To)... and the sliding cam with a ladder shape larger than the clutch pawl cap on the front surface of the flange-like part @ (To)
The boss part of the sliding body (A) having ... is fixed, and the spline (to) of the cylindrical part OD has a sliding member on the rear surface that engages with the sliding cam @ (to)... A ring-shaped driving body 6υ having a moving cam 4 . Spring that biases forward
will be established.

Further, a bearing (2) supporting the outer circumferential surface of the exterior body boss portion C13 is provided at the flange portion (toward) of the rear wall of the front transmission case OQ.
is provided, and the front wall of the flange part (to) has an insertion hole for the sliding body (A) in the front wall part, and is connected to the case of the automatic switching mechanism (7) that covers the outer periphery of the exterior body. And in this case (
In the insertion hole of (g), a sealing body () is provided which provides a certain resistance to the rotation of the sliding body (a).

A case having a bearing for supporting the front part of the driven shaft is connected to the front wall of the case, and the front side between the sliding bodies on the driven shaft is connected to the front wall of the case. is provided with a thrust bearing (G), and above the front side of this thrust bearing (G) is provided with a support shaft for a regulating mechanism (8) that is rotatably supported by the case bracket. is fixed to the arm (rθ) that presses the sliding body non-slidably through the thrust bearing, and the arm (rθ) is fixed to the − side end of the support shaft (to).
/) is provided with an operating lever (Ω) of the regulating mechanism (8) that can be locked in the rotational position. Further, the front end of the driven shaft (to) and the protruding part of the input shaft (to) are connected by a front wheel transmission shaft (6) having universal shaft coupling shafts at both front and rear ends.

Next, the effect will be explained. The clutch a4, which is transmitted to the output shaft α2 of the prime mover (13), is connected to the transmission mechanism (1g, variable speed transmission mechanism (3), rear shaft differential mechanism surface and transmission case (5)
The power is transmitted to the left and right rear shafts (2) (2) via the transmission mechanism in (5).

On the other hand, from the end transmission shaft (to) of the speed change transmission mechanism (3), there is a spline rotor l of the exterior body, and a sliding cam of the drive body Ωυ.
-... Transmission is transmitted to the driven body through the sliding cam @ (to) of the sliding body (T)... and both clutch claws (to) (to), and further from the driven body to the driven shaft ( ), the front power shaft (6) via the universal joint, the front wheel transmission shaft (6) and the
2), and from the input shaft (2) to the front wheel differential mechanism (5)
, is transmitted to the left and right front wheels (1) (1) via the transmission shaft Q4 (to) and the steering transmission mechanism I2e@.

As mentioned above, the front wheel (1) (1) is in the driving state when the driving body rotates in one direction ←υ sliding cam @ (to)... resistance is applied to the driving surface of the seal body). Receiving sliding body (G)
The driven surface of the sliding cam @ (to) makes contact and the thrust of the cam slope causes the sliding body (g) to slide backward against the spring (rotation), so the clutch of the sliding body chrysanthemum The claw (to) (to)... and the driven clutch claw (to) (to)...
... is maintained and the transmission is transmitted from between the sliding bodies to the driven body (b).

For example, when a tractor turns, the braking operation of the - side rear wheel (2) causes the rear wheel differential mechanism (1η) to move the other side rear wheel (2).
When the ground running speed of the vehicle doubles, the front wheels (1) (1) are pushed forward by the rear wheels (2), so the reverse transmission from the front wheels (1) (1) causes the sliding body part sliding cam... A gap is created between the driven surface of the driving body 6υ sliding cam @ (to)... and the thrust from the cam slope is lost, so the sliding body (a) slides forward due to the spring force. As a result, the clutch pawl e120Q of the sliding body (G) is disengaged from the clutch pawl (to) (to) of the slave corporal punishment (to)..., so the front wheel +1) (1) becomes in a free state where no power is transmitted. .

Also, after turning, when the ground speed of the rear wheels (2) (2) is restored to normal speed, there is no reverse power transmission from the front wheels +1) (1), so the same action as above causes the clutch claw (to)
(to)... are engaged, and the front wheels (1) (1) are in a transmission state.

Also, when the arm (If) is locked in the backward rotation position by operating the operating lever P position, the sliding body (A) will slide while both clutch claws (To) (To) are engaged. Since the driven shaft is immobile, the driven shaft is driven by the transmission path.

In other words, it's always in four-wheel drive.

[Brief explanation of drawings]

The figures show one embodiment of the present invention, in which FIG. 1 is a side sectional view, and FIGS. 2 and 3 are partial side sectional views. FIG. 4 is a side view of the whole. In the figure, (1) is the front wheel, (2) is the rear wheel, (3) is the transmission mechanism, (4) is the transmission case, (5) is the front wheel differential mechanism, (6) is the front wheel transmission shaft, (7) is an automatic switching mechanism;
(8) indicates the regulatory mechanism.

Claims (1)

[Claims] It is located between a pair of left and right front and rear wheels (1), (1), (2) and (2), and controls the transmission mechanism (3) for these front and rear wheels (1), (1), (2), and (2). A front wheel differential mechanism (5) is located on the front side of the internally installed transmission case (4) and is transmitted from the transmission mechanism (3) and located between the left and right front wheels (1).
In a tractor traveling transmission device that is provided with a front wheel transmission shaft (6) in the longitudinal direction that transmits power to When the ground running speed of the rear wheels (2) (2) exceeds a certain range, whether in forward or reverse direction, the power transmission to the front wheel transmission shaft (6) is automatically stopped. an automatic switching mechanism ( 7), and a regulating mechanism (8) for regulating the automatic switching mechanism (7) to the entry side state by an operating means is provided at the front part of the automatic switching mechanism (7). Traveling transmission device.