JPH04271970A - Working vehicle - Google Patents

Abstract

PURPOSE:To surely carry out parking operation by arranging a transmission side gear for receiving the positive rolling power for straight advance and a reduction speed side gear for receiving the positive rolling power at a low speed from a pair of reduction mechanisms, for a pair of side gears for transmitting power to the left and right traveling devices in pair and constituting the side gear so as to be operated in slidable manner over the range from the meshing position with the transmission side gear to the meshing position with the reduction speed side gear, in a working vehicle. CONSTITUTION:A main brake 49 which applies a brake to a reduction speed side gear is installed, and the left and right side gears are meshed with the reduction side gear and the operation of a main brake 49 is operated by the operation of a manual operating tool 50. Accordingly, a selecting means 54 which selection-operates a reduction speed mechanism to a transmission cut-off state (selection lever 43 at a neutral position N1) in interlocking with the operation of the manual operating tool 50 is provided.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work vehicle equipped with a pair of left and right crawler or multi-wheeled traveling devices.

0002

[Prior Art] A combine harvester, which is one of the above-mentioned work vehicles, is equipped with a pair of crawler-type traveling devices on the left and right, and is configured to drive one traveling device at a lower speed than the other to perform gentle turns. There are some structures, and their structures are as follows. In other words, as shown in FIG. 3, the left and right side gears 21L transmit power to the left and right traveling devices 24.
, 21R are engaged with the transmission gear 19, power flows to both traveling devices 24 in a normal rotation state via the input gears 23R, 23L and the axles 22R, 22L, and the aircraft moves straight. For example, when the left side gear 21L is slid to engage the left reduction gear 26L and the hydraulic clutch 30 is engaged, low-speed power from the upper reduction mechanism 40 is transmitted through the gear 29 to the left reduction gear 26L. and is transmitted to the left side gear 21L. As a result, the left traveling device 24 is driven at a low speed, and the aircraft slowly turns to the left due to the speed difference between the left and right traveling devices 24. Furthermore, by operating an artificial operating tool such as a brake pedal or a brake lever, the left and right side gears 21L and 21R are slid to engage with the left and right deceleration side gears 26L and 26R, and then
The left and right deceleration side gears 26L, 26R are controlled by the main brake 49.
It is also configured so that the aircraft can be parked by applying the brakes.

0003

[Problems to be Solved by the Invention] When a parking operation is performed using the above-mentioned manual operation tool immediately after the completion of a gentle turn by driving one of the traveling devices at low speed in the above-mentioned work vehicle, the following occurs. Problems may arise. In other words, as shown in FIG. 3, for example, the left side gear 21L is
When performing a parking operation immediately after making a slow turn with 6L engaged,
The main brake 49 is engaged and operated while the left side gear 21L remains engaged with the left reduction gear 26L and the right side gear 21R remains engaged with the right reduction gear 26R. In this case, the right reduction side gear 26R is connected to the hydraulic clutch 30 and the reduction mechanism 40 via the gear 29 and the transmission shaft 27.
Therefore, when the hydraulic clutch 30 and the speed reduction mechanism 40 are in the transmission state, the right speed reduction side gear 26R is also driven at a low speed. Therefore, if the right side gear 21R is slid to engage the right reduction side gear 26R as described above without performing the transmission cutting operation of the reduction mechanism 40, the right side gear 21R will also be driven at a low speed. In addition, the left side gear 21L, which is engaged with the left reduction side gear 26L, has been driven at a low speed for some time, so even if the main brake 49 is applied, the aircraft will move forward at a low speed against this. Therefore, there is room for improvement in terms of safety. An object of the present invention is to provide a structure that prevents the aircraft from moving forward when a parking operation is performed using a human operating tool.

0004

[Means for Solving the Problems] The present invention is characterized in that a work vehicle equipped with the above-mentioned deceleration mechanism and main brake is constructed as follows. In other words, a main brake capable of braking the deceleration side gear is provided, and the left and right side gears engage with the deceleration side gear by the operation of the manual operation tool, and the main brake is engaged and operated. A switching means is provided for switching the speed reduction mechanism to a transmission cut-off state in conjunction with the operation.

[0005]

[Operation] With the configuration described above, when the left and right side gears are engaged with the reduction side gears and the main brake is applied and operated using the manual operation tool, the switching mechanism operates the upper side reduction mechanism to the transmission disengaged state. Therefore, low-speed power no longer flows to the reduction side gear where the left and right side gears engage. This allows the main brake to reliably stop and hold the deceleration gear, making it possible to perform a reliable parking operation.

[0006]

[Effects of the Invention] As described above, when the human operating device for parking operation is operated, it is now possible to reliably stop and park the machine without moving it forward, thereby improving the safety of the work vehicle. I was able to do that.

[0007]

Embodiments Hereinafter, embodiments of the present invention will be explained based on the drawings. Figure 3 shows the structure inside the transmission case 8 of the traveling system of a combine harvester, which is one of the working vehicles.
Power from the hydrostatic continuously variable transmission 1 is transmitted via a belt transmission mechanism (not shown) equipped with a tension clutch.
At the same time, the power from the output shaft 3 of the hydrostatic continuously variable transmission 1 is transmitted to the reaping section 6 via the first transmission shaft 4.

Power from the first transmission shaft 4 is transmitted to the second transmission shaft 11 via the first gear 9 and the second gear 10. A shift gear 14 is slidably fitted on the second transmission shaft 11 with a spline structure, and the first high-speed gear 1
2 is fitted on the outside so as to be relatively rotatable. On the other hand, a second high speed gear 16, a medium speed gear 18, and a low speed gear 17 are fixed to the third transmission shaft 15, and the first high speed gear 12 and the second high speed gear 16 are engaged with each other. With the above structure, the gear shift type transmission device 35 shifts the power into three stages of high, medium and low by sliding the shift gear 14 and engaging the first high speed gear 12, medium speed gear 18 and low speed gear 17.
This power is transmitted to a third gear 19 (corresponding to a transmission gear) that meshes with the medium speed gear 18. As shown in FIGS. 1 and 4, a shift lever 45 for slidingly operating the shift gear 14 of the transmission 35 is provided.

A right side gear 21R and a left side gear 21L are fitted onto the support shaft 20 supporting the third gear 19 so as to be relatively rotatable, and the input gears 23R, 23L of the left and right axles 22L, 22R are connected to the left and right side gears 21L, 21R
is in constant occlusion. As a result, the right or left side gears 21R, 21L are slid to engage and separate from the third gear 19, thereby transmitting and interrupting power to the crawler-type traveling device 24. Side clutch 2 between left and right side gears 21L and 21R
5R and 25L are configured.

As shown in FIG. 3, the support shaft 20 has a right fourth gear 26R (corresponding to the reduction gear) and a left fourth gear 26L (
A pair of fifth gears 29 fixed to the fourth transmission shaft 27 mesh with the right fourth gear 26R and the left fourth gear 26L. . A sixth gear 37 is fitted onto the fourth transmission shaft 27 so as to be relatively rotatable, and the sixth gear 37 and the fourth transmission shaft 2
A hydraulic clutch 30 (corresponding to a speed reduction mechanism) is provided between the motor and the motor 7.

On the other hand, a shift gear 5 is externally fitted onto the third transmission shaft 15 in a spline structure, and the shift gear 5 is positioned at a position where the shift gear 5 engages with a seventh gear pair 38 which engages with a sixth gear 37; It is constructed so that it can be slid freely over three positions: a position where it engages directly with the gear 37, and a neutral position where it does not engage with any of them. 7th gear pair 38 is mission case 8
The shift member 13 is fitted onto a fixed shaft 7 fixed to the fixed shaft 7 so as to be relatively rotatable, and the shift member 13 fitted onto the fixed shaft 7 with a spline structure is engaged with the seventh gear pair 38, thereby shifting the seventh gear pair. 38 can be fixed.

Next, a configuration for applying braking to one axle 22R or 22L will be explained. As shown in FIG. 3, when the shift member 13 is engaged with the seventh gear pair 38, the sixth gear 37 is in a fixed state (the shift gear 5 is in the neutral position). As a result, when the hydraulic clutch 30 is engaged and operated with the right side gear 21R or the left side gear 21L separated from the third gear 19 and engaged with the right fourth gear 26R or the left fourth gear 26L, one of the axles 22R or 22L is engaged. Braking is applied. This is the turning state.

Next, a configuration for reversing one axle 22R or 22L will be explained. As shown in FIG. 3, when the shift gear 5 is directly engaged with the sixth gear 37, the power from the third transmission shaft 15 is transmitted to the sixth gear 37 in a reversed state and at a speed reduced to 1/2. (The shift member 13 is separated from the seventh gear pair 38). As a result, the right side gear 21R
Alternatively, the left side gear 21L can be replaced with the right fourth gear 26 as described above.
When the hydraulic clutch 30 is engaged and operated with the R or left fourth gear 26L engaged, the axle 22R or 22L is driven in a reversed state and decelerated to 1/2. And this is the state of super confidence turning.

Next, a description will be given of a configuration in which one axle 22R or 22L is driven to rotate normally at a lower speed than the other. As shown in FIG. 3, when the shift gear 5 is engaged with the seventh gear pair 38 which is engaged with the sixth gear 37, the forward rotational power from the third transmission shaft 15 is reduced to 1/2 and transferred to the sixth gear 37. is transmitted (the shift member 13 is separated from the seventh gear pair 38). As a result, when the hydraulic clutch 30 is engaged with the right or left side gears 21R, 21L engaged with the right or left fourth gears 26R, 26L, one of the axles 22R or 22L is driven at a low speed. And this is a slow turning state,
The speed reduction mechanism 40 is formed by the shift gear 5, the seventh gear pair 38, etc.
is configured.

Next, a structure for supplying hydraulic oil to the hydraulic clutch 30 and the hydraulic cylinders 31R, 31L for sliding the left and right side gears 21L, 21R will be explained. Figure 2
As shown in FIG. 3, the hydraulic oil from the pump 32 is supplied to the hydraulic cylinders 31R, 31L for the left and right side gears 21L, 21R via the switching valve 33, and the oil passage 34 from the side of the hydraulic cylinders 31R, 31L is connected to the hydraulic clutch. 3
Connected to 0. Furthermore, a variable relief valve 36 for the hydraulic clutch 30 is connected to the oil passage 34 . Next, operations of the switching valve 33 and the variable relief valve 36 will be explained. As shown in FIG. 2, a swing-type operating arm 28 for operating the variable relief valve 36 to the closing side is provided, and this operating arm 28 and an operating lever 39 are connected to a wire 4.
1 is mechanically linked. Furthermore, the operating lever 39 and the switching valve 33 are mechanically linked by a linkage mechanism 42.

The state shown in FIGS. 1 and 2 is a state in which the switching lever 43 for operating the shift gear 5 and the shift member 13 is operated to the slow rotation position, and the shift gear 5 is engaged with the seventh gear pair 38. This is a state in which low-speed normal rotational power is being transmitted to the sixth gear 37. In this state, the operating lever 39
When the switch is operated from the neutral position N to the first right turning position R1 or the first left turning position L1, only the switching valve 33 is operated and the right or left operating part 46 is operated by the hydraulic cylinder 31R or 31L.
The right or left side gears 21R, 21L that were engaged with the third gear 19 are separated from the third gear 19 via R, 46L, and are engaged with the right or left fourth gears 26R, 26L.

In this case, since the variable relief valve 36 is fully open and the hydraulic clutch 30 is disengaged, the power transmission to the right or left axles 22R, 22L is cut off (
(side clutch 25R or 25L is disengaged), and the aircraft slowly changes direction to the right or left. Further, the sequence valve 47 provided in the oil passage 34 is configured such that the right or left side gears 21R, 21L are connected to the right or left fourth gear 26R,
This is to ensure that the hydraulic cylinders 31R and 31L have the pressure necessary to completely engage the cylinder 26L.

Next, when the operation lever 39 is operated from the right or left first rotation position R1, L1 to the right or left second rotation position R2, L2, the operation arm 28 is moved to the position shown in FIG. The variable relief valve 36 is operated to the closing side by being oscillated clockwise in the paper. As a result, the hydraulic clutch 30 starts to be engaged and operated, and the right or left axle 22
R and 22L are gradually driven forward at low speed, and the aircraft slowly turns to the right or left. Then, when the operating lever 39 is in the right or left second turning position R2, L2, the hydraulic clutch 30 is fully engaged.

As shown in FIGS. 1 and 4, FIG.
A shift lever 45 for the transmission 35 is swingably supported around an axis P1, and a restraining arm 46, which is L-shaped in plan view, is swingably supported around an axis P2 perpendicular to the axis P1. This check arm 46 and the switching lever 4
3 are linked by a wire 48.

With the above structure, when the switching lever 43 is operated to the slow rotation position as shown in FIGS. 1 and 4, the check arm 46 enters the operation path of the gear shift lever 45. As a result, the speed change lever 45 can only be operated to a medium speed position and a low speed position, and cannot be operated to a high speed position. Conversely, even if you try to operate the switching lever 43 to the slow swing position while the shift lever 45 is being operated to the high speed position, the check arm 46 will come into contact with the shift lever 45, so the switching lever 43 will not be moved to the slow swing position. It can not be operated.

Furthermore, as shown in FIG.
contacts the shift lever 45 in a state oblique to the operating path of the shift lever 45 when viewed from above, and the check arm 46 is obliquely oblique to the shift lever 45 when viewed from the front as shown in FIG. Therefore, when the shift lever 45 is operated to the high speed position in the state shown in FIGS. 1 and 4 (with the shift lever 45 in the medium or low speed position and the switching lever 43 in the slow rotation position), The check arm 46 is lifted and the switching lever 43 is returned to the neutral position N1 and operated. This neutral position N1 is an intermediate position between a pivot turning position and a slow turning position, which will be described later, and is a position before the shift gear 5 is separated from the seventh gear pair 38 in FIG. It is. In this state, no power flows to the lower sixth gear 37 and the hydraulic clutch 30, and the right and left fourth gears 2
Since 6R and 26L are in a free rotating state, the operating lever 3
9 is operated to the right or left second turning position R2, L2, a slow turning state does not occur.

Next, the pivot turning state will be explained. Figure 1
As shown in FIG.
is engaged with the seventh gear pair 38 to fix the sixth gear 37, and the shift gear 5 is placed in the neutral position. In this state, when the operating lever 39 is operated from the neutral position N to the right or left first turning position R1, L1, the side clutch 25R or 25L is disconnected as described above, and the aircraft gently turns to the right or left. I'm going to change it. Next, when the operation lever 39 is operated to the right or left second rotation position R2, L2, the variable relief valve 36 is gradually operated from the fully open state to the closed side. As a result, the hydraulic clutch 30 is engaged and operated,
Braking is gradually applied to the right or left axles 22R, 22L, and the aircraft turns to the right or left. Then, the braking force becomes maximum at the right or left second turning position R2, L2 of the operating lever 39.

Next, the super-turning state will be explained. As shown in FIG. 1, the switching lever 43 is operated to the super pivot position to separate the shift member 13 from the seventh gear pair 38 and cause the shift gear 5 to engage directly with the sixth gear 37. In this state, when the operating lever 39 is operated from the neutral position N to the right or left first turning position R1, L1, the side clutch 25R or 25L is disconnected as described above, and the aircraft gently turns to the right or left. I'm going to change it. Next, when the operation lever 39 is operated to the right or left second rotation position R2, L2, the variable relief valve 36 is gradually operated from the fully open state to the closed side. As a result, the hydraulic clutch 30 is engaged and operated,
The right or left axles 22R, 22L are driven in reverse, and the aircraft makes a sharp turn to the right or left.

As shown in FIGS. 1 and 3, the fourth power transmission shaft 2
A main brake 49 for parking is provided at one end of 7.
A brake pedal 50 (corresponding to a human operating tool) and a main brake 49 are linked by a wire 51. The inner end of another wire 52 is connected to the brake pedal 50, and the inner end of this wire 52 on the other end side is connected to the right operating section 46R shown in FIG. 2, and the outer end is connected to the left operating section 46L. With the above structure, when the brake pedal 50 is depressed and operated, the left and right operation parts 46R and 46L
The right and left side gears 21R, 21L are engaged with the right and left fourth gears 26R, 26L, and the main brake 4
9 is entered and operated. A parking operation can be performed by fixing the brake pedal 50 at the depressed position using the lock member 53.

In this case, as shown in FIG. 1, a rod-shaped linkage mechanism 54 (corresponding to a switching mechanism) that can be operated by pushing the switching lever 43 is connected to the brake pedal 50. With the above structure, when a parking operation is performed using the brake pedal 50 while the switching lever 43 is operated to the slow turning position as described above, the switching lever 43 is activated by the linking mechanism 54.
3 is operated to the neutral position N1. In this case, the power transmission is cut off at the left and right side clutches 25R, 25L and the speed reduction mechanism 40, so the engine does not stop, and the power from the engine is transmitted to the reaping section 6 via the hydrostatic continuously variable transmission 1. Therefore, the grain culms remaining in the reaping section 6 are sent as they are to a threshing device (not shown) for processing.

[Another Embodiment] In the above-mentioned embodiment, the shift gear 5, the shift member 13, etc. are regarded as the deceleration mechanism 40, and when the brake pedal 50 is depressed and operated, this deceleration mechanism 4
The hydraulic clutch 30 in FIG.
It may be configured such that when the brake pedal 50 is depressed, the hydraulic clutch 30 is unloaded. Further, a brake lever may be used as the manual operating tool 50 instead of the brake pedal 50.

Although reference numerals are written in the claims for convenience of comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

[Fig. 1] A diagram showing the interlocking state of a switching lever for selecting a turning state, a shift lever for a transmission, and a brake pedal for a main brake.

[Figure 2] Hydraulic circuit diagram showing the interlocking state of the steering control lever, hydraulic cylinders for left and right side gears, and hydraulic clutches

[Figure 3] Schematic diagram showing the transmission structure inside the mission case

[
Figure 4: Plan view of the gear lever and restraint arm for the transmission

[Explanation of symbols]

19 Transmission side gear 21R, 21
L Side gear 24 Traveling device 26R, 26L
Reduction side gears 30, 40 Reduction mechanism

Claims (1)

[Claims] [Claim 1] A pair of left and right side gears (21R) and (21L) that transmit power to a pair of left and right traveling devices (24).
For each of the transmission side gears (19), which receive normal rotational power for straight travel, and a transmission side gear (19) that receives normal rotational power from a pair of reduction mechanisms (30) and (40) at a speed lower than the normal rotational power of the transmission side gear (19). Reduction side gears (26R), (26L) that receive normal rotational power are arranged, and the side gears (21R), (21L) are aligned with the meshing position with the transmission side gear (19) and the reduction side gears (26R), (
The work vehicle is configured to be able to slide freely over the occlusion position with the reduction side gear (26R).
, (26L) is provided, and the left and right side gears (21R), (21L) are moved to the deceleration side gears (26R), (21L) by operating the human operating tool (50).
26L) and is linked so that the main brake (49) is engaged and operated, and the manual operation tool (49) is engaged with the main brake (49).
The reduction mechanism (30), (40)
) to a transmission cut state.