JPH03531A - Power vehicle running transmission device - Google Patents

Abstract

PURPOSE:To properly facilitate turning and running operations with switch-over automatically made between two wheel drive four wheel drive by providing a speed sensor which controls an automatic switch-over means to a front wheel power transmission shaft to be brought into an engaged condition based on the running speeds of rear wheels. CONSTITUTION:Power is transmitted to a driven body 37 from a trailing end power transmission shaft 29 via a spline shaft 30, the sliding cams 39 of a drive body 41 and a slider 40 and both of clutch pawls 36, and is also transmitted to a front wheel input shaft via a driven shaft 35. When the braking operation of one rear wheel forces the ground 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, a gap is thereby made between the respective cams 39 of the slider 40 and the drive body 41, the clutch pawl 39 of the slider 40 comes off from the clutch pawl 36 of the driven body 37 with the slider 40 slid so that front wheels are conditioned to no power transmission. When a speed sensor 9 detects revolutions less than the definite range of the trailing end power transmission shaft 29, an arm 51 is rotated afterward, and the respective clutch pawls 36 of the slider 40 and the drive body 37 are meshed with each other so that the drive condition of the front wheels can thereby be maintained.

Description

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

PRIOR ART AND PROBLEMS TO BE SOLVED BY THE INVENTION In a so-called four-wheel drive tractor, for example, 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 is equipped with 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. It's necessary and troublesome.

However, for example, when so-called dashing occurs during rotary plowing work performed at low speeds, or when climbing or descending at low speeds, it is preferable to use four-wheel drive mode due to the traction force and braking force. Therefore, an object of the present invention is to provide a mechanism that can automatically switch from a two-wheel drive state to a four-wheel drive state in such a case, in addition to solving the above-mentioned problems.

Means for Solving the Problems This invention provides a pair of left and right front and rear wheels <1) (1) (2
) (located between 21, these front and rear wheels (1) (1)
(2) The transmission is transmitted from the transmission mechanism (3) to the front side of the transmission case (4) in which the transmission mechanism (3) of (2) is installed, and between the left and right front wheels (1) (1). The front wheel transmission shaft in the longitudinal direction transmits power to the located front wheel differential mechanism (5)
6) In the tractor traveling transmission device provided with the above-mentioned speed change transmission mechanism (3) and the front wheel transmission shaft (6), there is a transmission mechanism between the front wheel transmission mechanism (3) and the front wheel transmission shaft (6). In this case, when the ground running speed of the rear wheels (2) (21) exceeds a certain range, the front wheel transmission shaft (6)
The transmission to the rear shaft (2) is automatically set to the cutting side, and the rear shaft (2)
An automatic switching mechanism (7) is provided which can automatically switch 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, and furthermore, this automatic switching mechanism (
7) includes a regulating mechanism (8) that regulates the automatic switching mechanism (7) to the entrance state, and a speed sensor (9) that detects a traveling speed below a certain range and regulates the regulating mechanism (8). )
A traveling transmission device for a tractor is characterized in that the following is provided.

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) (21), 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 axle 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 side rear axle (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 (2) (21) are in two-wheel drive mode, the turning radius is smaller than in the case of four-wheel drive.Also, after turning, the rear wheels +21) (2) When the ground running speed is restored to normal speed, the automatic switching mechanism (7) automatically transmits power to the front wheel transmission shaft (6), that is, the four-wheel drive state is established.

Further, when the speed sensor (9) detects a low traveling speed during rotary tilling work, for example, the speed sensor (9) operates the regulation mechanism (8), so that the automatic switching mechanism (7) is activated.
automatically moves to the entry side and transmits power to the front wheel transmission shaft (6), that is, becomes a four-wheel drive state.

Effects of the invention Due to these effects, when two-wheel drive is required,
Since switching between four-wheel drives is automatically performed whenever four-wheel drive is required, there is no need to perform a switching operation each time, unlike the problem described above, and this makes turning and driving operations appropriate and easy.

Example Note that when the vehicle is rotated, the frame forming the front part of the vehicle body (
1) A prime mover (13) having an output shaft (121) protruding rearward is mounted on the rear end of the prime mover 03+ and the frame (1). A front transmission case 4 in which a clutch 04 that is transmitted from the clutch u4 and a transmission mechanism (19) that is transmitted from this clutch u4 is coupled, and the rear end of this front transmission case (le is equipped with the transmission mechanism 09 A speed change transmission case (4) containing a speed change transmission mechanism (3) that transmits power from the speed change transmission mechanism (3) is connected to the rear end of the speed change transmission case (4). The wheel differential mechanism (rear transmission case (1) 1 with one sword inside) is combined, and this rear transmission case + IEI
On the upper side of the
91! Cylinder case +2 (I is installed) containing a hydraulic cylinder that transmits power to +91.

On the lower side of the frame (1) 1, there is a pin I2 in the front and back direction.
The support body (2a is provided, and the pin 121 of this support body Qδ) has a front shaft input shaft that projects rearward, and the front wheel drive shaft that is transmitted to this input shaft (towards) has a front shaft input shaft that projects rearward. A shaft case ?9 containing a differential mechanism (5) and a pair of left and right transmission shafts 124) (241) which are transmitted to the differential mechanism (5) is swingably supported, and both left and right ends of the shaft case 4 are The front wheel (1) installed in the steering transmission mechanism ee I2e is
(1) respectively, and on both left and right sides of the rear transmission case (IEI, there is a transmission case installed inside the transmission mechanism that transmits to the rear axle differential mechanism (17)). Ring +2
1 +21 are provided respectively.

The terminal transmission shaft (2) of the speed change transmission mechanism (3) is attached to a bearing (to) provided at the lower part of the front wall of the speed change transmission case (4).
! 6, and the front end of this transmission shaft 121 has a
Automatic switching mechanism consisting of a cylindrical part Gυ having a spline Ol on the front part of the inner peripheral surface, a wall part (support) at the rear end of this cylindrical part 0υ, and a boss part 03 that projects rearward from this wall part (support). (7) Spline the boss portion of the exterior body.

Further, the axial bearing part (b) provided at the front end of the transmission shaft 121 supports the small diameter part of the rear end of the driven shaft (to), and the rear part on this driven shaft (g) supports the small diameter part of the rear end of the driven shaft (to). , the boss part of the driven body (b) having a radially ladder-shaped clutch pawl os OQ... is spline-coupled to the front surface of the flange-like part, and the boss part of the driven body (b) is connected to the driven shaft (to) on the front side of the driven body (b). , this driven shaft is 0
9 is provided with a sliding and rotatable bearing (to), and on the outer peripheral surface of this bearing (to) is a clutch pawl oO that engages with the clutch pawl (to) Oe... on the rear surface of the flange-shaped part. (
)...and the clutch pawl (
(to) (a) Ladder-shaped sliding cam 01 @ larger than...
. . . A sliding cam 01091 . )... is fixed to the ring-shaped driving body 6υ, and between the exterior body wall part (support) and the flange-shaped part of the sliding body (g),
A spring is provided to bias the sliding body (a) forward.

Also, the flange portion i43 of the rear wall of the front transmission case iIQ
A bearing for supporting the outer circumferential surface of the exterior body boss portion 03 is provided, and a front wall of the flange portion 03 has an insertion hole for the sliding body (G), and the exterior body A case (g) of the automatic switching mechanism (7) that covers the outer periphery of the sliding body is connected, and a sealing body that provides a certain resistance to rotation between the sliding bodies is provided in the insertion hole of the case area.

A case having a bearing (2) for supporting the front part of the driven shaft is coupled to the front wall of the case area, and a front side of the sliding body (G) on the driven shaft (T) is connected to the case. Thrust bearing (G)
A support shaft for a regulating mechanism (8) rotatably supported by the case (to) is provided above the front side of the thrust bearing (to), and on this support shaft, the thrust bearing Bearing (to)
A1-t that presses the sliding body I4G so that it cannot slide through
Fix j″θ.

In addition, near the end transmission shaft I21 of the speed change transmission mechanism (3), the arm (♂θ) of the regulation mechanism (8) is moved backward by detecting the rotation speed of the end transmission shaft (to) below a certain range. A speed sensor (9) that can be rotated is provided, and the front end of the driven shaft (to) and the protrusion of the input shaft (to) have flexible pivot legs f#)C#) at both front and rear ends. They are connected by a front wheel transmission shaft (6).

Next, the effect will be explained. Output shaft 0 of prime mover (13)
The clutch a gradient that is transmitted to the left and right rear wheels is transmitted through the transmission mechanism (151, speed change transmission mechanism (3), rear wheel differential mechanism (+7), and transmission mechanism in the transmission case (5) (5). (2
) (2).

On the other hand, from the terminal transmission shaft (29) of the variable speed transmission mechanism (3),
Spline of the exterior body (to), sliding cam of the driver uO @(
(to)...The sliding cam @ (to) of the sliding body (g)... and both clutch claws C3Q Of)... are transmitted to the driven body (b), and then from the driven body - to the driven shaft. 09, Universal shaft joint hair (24 (24 and steering transmission mechanism 12
Power is transmitted to the left and right front wheels +1) (1) via e+2G.

As mentioned above, when the front wheels (1) (1) are driven, the driving surface of the driving body 6υ sliding cam @(to)... which rotates in one direction receives resistance from the seal body). The driven surface of the sliding cam @ (to) comes into contact with the sliding body, and the thrust of the cam slope causes the sliding body (a) to slide backward against the spring (4). Clutch pawl Ge of moving object (G)
t3Q... and the clutch pawl of slave corporal punishment as OQ-...
The meshing with the sliding body (a) is maintained and the transmission is transmitted from the sliding body (a) to the driven body (-).

For example, when a tractor turns, the braking operation of the - side rear wheel (2) causes the rear wheel differential mechanism (17) to act on the other side rear axle (2).
) becomes twice as fast, 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 (g) sliding cam @( To)・
A gap is created between the driven surface of ... and the driving surface of the driving body @+1 sliding cam @ (to)..., and the thrust from the cam slope is lost, so the sliding body slides forward with spring f421. From the clutch pawl oeoQ of the driven body to the sliding body (
The clutch pawl C3Q (3G... When the speed is restored, there is no reverse power transmission from the front wheels (1) (1), so both clutch pawls 090e are engaged by the same action as described above, and the front wheels (1) (1) become in a transmission state.

Also, when the speed sensor (9) detects the rotation speed of the end transmission shaft (c) below a certain range, that is, the low running speed below a certain range,
The arm (j/) of the regulating mechanism (8) is rotated backward to press and slide the sliding body (g) backward.
The clutch pawl of (g) (to) (to)... and the clutch pawl @ (to) of driven body (b) mesh with each other, which means that the front wheel cannot move forward due to the sliding body (material) not being able to slide forward. (IHI)
The driving state of is maintained.

Note that the above is an example in which a speed sensor (9) is provided, but in response to running up and down a slope or running tilted to the left or right with respect to the direction of travel, the regulation mechanism detects a tilt of the vehicle body beyond a certain range. (8), or a position sensor that detects the set gear shift position of the gear shift lever (J) that operates the gear change transmission mechanism (3) and regulates the regulation mechanism (8). good.

Fig. 5 shows both foot pedals (17) (l?) that can brake the left and right rear wheels (21) 21 by foot operation, and the - side petal (17) can brake the left and right rear wheels (21) 21 by turning. petal (σ
A connection J41tT) that can connect layers is pivotally connected, and this connection tool m
A sensor @t is provided near the connection J41#) to detect the connection of the connection X4W) and operate the regulation mechanism (8).
If Mt is operated simultaneously, the left and right rear wheels (2) (21
is braked, and the rear wheels (from 21+21 to the front wheels
Since the front wheels (1) (1) are also braked via each transmission system including (1), the braking force of the vehicle body is improved.

[Brief explanation of the drawing]

The figures show one embodiment of the present invention, in which Fig. 1 is a side sectional view, Figs. 2 and 3 are partial side sectional views, Fig. 4 is an overall side view, and Fig. 5 is a side sectional view. FIG. 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) shows a regulation mechanism, and (9) shows a speed sensor.

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 the automatic switching mechanism (7) further includes a regulating mechanism (8) that regulates the automatic switching mechanism (7) to the entry state, and a regulating mechanism that detects a traveling speed below a certain range and switches the regulating mechanism to the entry state. A traveling transmission device for a tractor, characterized in that it is provided with a speed sensor (9) for regulating (8).