JPH099749A - Speed change operational device in farm working machine - Google Patents

Abstract

PURPOSE: To provide the subject relatively lightweight speed change operational device capable of conducting a change-over operation for advance/retreat at low cost so as to be applicable even to an inexpensive kind of machines, designed to reasonably link to the forced raising actuation of a working device as a result of retreat. CONSTITUTION: This speed change operational device is equipped with a synchronous-type advance/retreat change-over mechanism and a hydraulic clutch on the transmission upper side thereof and is so designed that the spool 17 of a clutch control valve is externally engaged with a shift fork and a change- over lever 40 is interlocked therewith. The spool 17 and the shift fork are mutually interlockingly linked so that the hydraulic clutch is temporarily let out as the advance/retreat change-over mechanism is transferred from one party to another among the advance and retreat positions F, R and neutral position N, and a flexibility is afforded so that the hydraulic clutch is let out prior to shift initiation. A hydraulic oil fed to the hydraulic clutch as a result of the retreating operation of the advance/retreat change-over mechanism is guided to a lift hydraulic cylinder 8 to rapidly raise a planting device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear shifting operation device for agricultural working machines such as rice transplanters and tractors, and more particularly, to a gear type driving gear shifting operation for facilitating and forcibly raising the working device associated with a reverse operation. The present invention relates to a technique for organically binding.

[0002]

2. Description of the Related Art For example, generally, as a gear shifting operation procedure of a traveling gear shifting mechanism of a working machine, first, a clutch pedal is depressed to disengage the main clutch, and then a gear shift lever is operated to shift a gear, and after the shifting is completed, The main method is to release the depression of the clutch pedal to engage the main clutch.

[0003]

In the above-mentioned operation structure, two kinds of operations of the shift lever and the clutch pedal are required, which may be troublesome. Therefore, the rice transplanter disclosed in Japanese Unexamined Patent Publication No. 7-52671 is disclosed. As described above, by providing the hydraulic clutch and the control valve for each shift stage, the control valve is operated to selectively operate the hydraulic clutch to shift gears, that is, a single operation and light shift operation can be performed. There is a so-called power shift structure. However, with this means, a hydraulic clutch is required for each gear, and the system is relatively expensive, so it is difficult to use for low-priced models.

Further, in the rice transplanter, in order to avoid contact with other objects of the working device associated with the backward movement of the agricultural work machine, such as when the planting device collides with the ridges in the backward movement, the working device follows the backward operation. Is equipped with a means for forcibly raising the work device. For example, as in the rice transplanter disclosed in Japanese Patent Laid-Open No. 6-237611, the reverse operation of the gear shift lever is detected by the switch and the control valve for raising and lowering the working device is raised. The technology to switch to is known. Therefore, the present invention provides a gear shift operating device that is relatively light and is capable of performing a forward / reverse switching operation at a relatively low cost so that it can be applied to a low-priced model.
The reason for this is that it is reasonably linked to the forced lifting operation of the work equipment associated with the reverse travel.

[0005]

A first invention for achieving the above object is to provide a gear type traveling speed change mechanism, a hydraulic clutch disposed on the transmission side of the gear type shift mechanism, and a shifter for the traveling speed change mechanism. It is equipped with an artificial operation system that shifts the shifter by manual operation, and the hydraulic clutch in the engaged state is temporarily disengaged as the shifter moves from one of the gear engagement position and the gear non-engagement position to the other. In order to ensure that the clutch control valve of the hydraulic clutch and the shifter are interlockingly linked, and the hydraulic clutch is disengaged prior to the shift start of the shifter, the manual operation system or the linked operation system is operated. In addition to providing flexibility in the interlocking part, the hydraulic oil for raising and lowering the working device is connected to the rear part of the machine to supply pressure oil to the hydraulic clutch when the traveling speed change mechanism is switched to the reverse side. As working device by directing the Sunda increases, it is characterized in that which had been linked to the clutch control valve and the hydraulic cylinder.

A second aspect of the present invention is the above structure,
With the shift mechanism for traveling being switched to the reverse side,
To change the lifting control valve of the hydraulic cylinder to the rising side,
This is because the elevation control valve and the artificial operation system are linked.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the hydraulic pressure supplied to hydraulic actuators other than the hydraulic clutch and hydraulic cylinder is changed to the hydraulic cylinder as the traveling speed change mechanism is switched to the reverse side. The hydraulic circuit of the hydraulic actuator and the clutch control valve are linked so that the work device is lifted up by being guided to.

[0008]

In any one of the structures of claims 1 to 3, the shift operation itself is performed manually, and the hydraulic clutch is automatically turned on and off in association with the operation, that is, so-called no-clutch shift operation means. is there. Compared with the manual operation means for performing both the speed change operation and the clutch operation by the manual operation and the automatic operation means for changing the speed with the actuator as described in the above-mentioned publication, the thing of the present application is, so to speak, a semi-automatic operation. Only one hydraulic clutch is required regardless of the number of stages. Then, due to the flexibility provided in the interlocking part of the manual operation system or the linkage operation system, the hydraulic clutch is linked so as to be disengaged before the shift start of the shifter, so that the gear engagement or disengagement is actually performed. When it is called, the clutch has already been disengaged, and a light shift operation without a driving load appears.

Further, the clutch control valve and the hydraulic cylinder can be linked with each other by using the above-mentioned clutchless speed change means, whereby the supply to the hydraulic clutch when the traveling speed change mechanism is switched to the reverse side. Since pressure oil is also supplied to the hydraulic cylinder for raising and lowering the working device, compared to the conventional method that switches the raising / lowering control valve to the ascending side after detecting the backward movement of the lever, the work is performed from the lever operation. It is possible to shorten the time required until the device starts to move up, and the responsiveness is improved. That is,
In reality, since the machine body moves backward after the lifting operation of the work device is started, the time from the reverse operation to the start of the machine reverse movement is shortened.

According to the second aspect of the present invention, since the raising / lowering control valve is also switched to the raising side, in addition to the pressure oil for operating the hydraulic clutch, the original pressure oil for raising is also joined to the hydraulic cylinder. Therefore, the working device can be quickly raised. Therefore, it is possible to further shorten the time from the backward operation to the start of the backward movement of the body.

According to the third aspect of the present invention, for example, the hydraulic oil supplied to hydraulic equipment other than the hydraulic clutch for shifting and the hydraulic cylinder for raising and lowering such as the power steering mechanism is added to the hydraulic oil for operating the hydraulic clutch to raise and lower the working device. Since it is supplied to the hydraulic cylinder, the working device can be quickly raised by the merging of the pressure oil. Therefore, it is possible to further shorten the time from the backward operation to the start of the backward movement of the body, as compared with the case of the configuration according to claim 1, and claim 2
It can be shortened as compared with the case of due to the configuration of.

[0012]

As a result, in the gear shift operating device according to any one of claims 1 to 3, the shift sequence is set such that the gear shift is performed after the hydraulic clutch is actuated. It was possible to provide a useful thing that can be constructed cheaply and can be used in a low-priced model in a state in which the response of the forcible ascending operation of the working device associated with the backward movement is improved by utilizing the clutch pressure.

The gear shift operation device according to the second or third aspect has the additional advantage that the response is further improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to the drawings when it is applied to a rice transplanter, which is an example of an agricultural working machine. A riding type rice transplanter is shown in FIG. 1, 1 is front wheels, 2 is rear wheels, 3 is a traveling body, 4 is an engine, 5 is a belt continuously variable transmission mechanism, 6 is a mission, 7 is a driver's seat, 8 is a lifting cylinder. , 9 is a lifting link mechanism, 10 is a steering handle, 11
Is a main gear shift lever, and A is a planting device.

The structure of the mission 6 is shown in FIGS. 2 and 3, and the auxiliary transmission mechanism B having two high and low stages extending from the input shaft 12 which is the driven shaft of the belt continuously variable transmission mechanism 5 and the first transmission shaft 13 to the second transmission mechanism B. 1
A forward / reverse switching mechanism C extending between the transmission shaft 13 and the second transmission shaft 14, a front wheel differential device D, and a vertical transmission shaft 15 for driving rear wheels are provided.

The forward / reverse switching mechanism C is of a synchronous meshing type, and the hydraulic clutch E provided on the first transmission shaft 13 is automatically turned on / off in association with the switching operation.
It is configured so that clutchless switching can be performed. The first transmission shaft 13 has a forward drive gear 16 and a reverse drive gear 1
8 and the shift fork 19 are fitted on the spline so as to be rotatable relative to each other. Second transmission shaft 14
A forward driven gear 20 and a backward driven gear 21 are fitted on the outer peripheral surface of the synchronizer 2 so as to be rotatable relative to each other.
2 is fitted on the spline, and a sleeve (corresponding to a shifter) 23 is fitted on the spline.

Further, a back shaft 26 is provided which spline-fits an intermediate drive gear 24 that meshes with the reverse drive gear 21 and an intermediate driven gear 25 that meshes with the reverse drive gear 18. Therefore, when the shift fork 19 is shifted to the right in FIG. 3, power is transmitted in the order of the forward drive gear 16 → the forward driven gear 20 → the synchronizer 22 to express the forward drive state, and the shift fork 19 is moved to the position shown in FIG. When the vehicle is shifted to the middle left, power is transmitted in the order of reverse drive gear 18 → intermediate driven gear 25 → intermediate drive gear 24 → reverse driven gear 21 → synchronizer 22 to reveal the reverse drive state.

The hydraulic clutch E is an inner body 27 integrally formed with the reverse drive gear 18, an outer body 28 spline-fitted to the first transmission shaft 13, and a slidable external fitting to the first transmission shaft 13. In addition to being configured as a multi-plate friction clutch including a piston 29, a delivery oil passage 30 for moving the piston 29 and a lubricating / cooling oil passage 31 are bored in the first transmission shaft 13. The control valve V of the hydraulic clutch E is constructed in the valve case 32 integrally attached to the transmission case 6a and has a structure in which the forward / backward switching operation is performed by the spool 17, which will be described in detail below.

As shown in FIG. 3, the shaft end of the first transmission shaft 13 is projected into the valve case 32, and the linearly moving spool 17 is supported in a state of penetrating the transmission case 6a. And two snap rings 3
The shift fork 19 is fitted onto the spool 17 so as to be relatively slidable within a predetermined range by 4, 4 and a return spring 33 interposed between the shift fork 19 and the snap rings 34, 34 on both sides. By 33, the shift fork 19 is urged to return to the spool 17 at a central position in a predetermined sliding range (between the pair of snap rings 34, 34). The return spring 33 is compressed and deformed to the limit in conjunction with the movement of the spool 17 by an artificial operation, and the return spring 33 is compressed and deformed in accordance with the neutral operation of the forward / reverse switching mechanism C to be in a free state. Its spring strength is set to return.

By the way, as shown in FIG. 11, the control valve 44 of the hydraulic cylinder 8 for raising and lowering the planting apparatus A and the reverse detection switch 45 for detecting that the switching lever 40 has been operated to the reverse position R are controlled. It is connected to the device 46 and constitutes a backward moving means 47. That is, when the switching lever 40 is operated to the reverse position R, the reverse detection switch 45 is activated to switch the control valve 44 to the raised position and raise the planting apparatus A to the upper limit.

As shown in FIGS. 3 to 6, at the end of the spool 17 on the side of the control valve V, the first and second lands 36, which have small diameters,
37, and first and second valve bodies 38, 39 that prevent oil from flowing.
Is formed, and a pump port P, a tank port T, a supply / discharge port K communicating with the delivery oil passage 30, and a merging port Q are formed respectively. Tank port T
Is communicated with the side of the transmission case 6a of the valve case 32 and oil is drained inside the transmission case 6a, the pump port P is guided to the side of the non-transmission case 6a, and the supply / discharge port K is the first transmission shaft. Land of 13 1
It is guided to 3a and communicated with the delivery oil passage 30.

The merging port Q communicates with the oil supply / drain passage 8a for the lifting hydraulic cylinder 8 via a check valve 48 (see FIG. 11), and the valve case 32 has a pump port P and a second tank port. A relief valve 35 that extends over T2 is installed. Although not shown, the second tank port T2 also has a structure in which oil is drained inside the mission case 6a. Incidentally, 31 is an oil passage for lubrication / cooling, and oil is ejected when the relief valve 35 is operated for relief.

A switching lever 40 for manual operation is interlocked with the other end of the spool 17, and this switching lever 40
The forward / reverse switching mechanism (an example of a gear shifting mechanism) C is switched by the manual operation of the forward movement (F), neutral (N), and reverse (R).
The respective states can be revealed, and the hydraulic clutch E is disengaged before the sleeve 23 starts moving by the operation of the switching lever 40. Next, the series of operations will be described together with the switching operation.

FIG. 7A shows the neutral state of the forward / reverse switching mechanism C when the switching lever 40 is operated to the neutral position N. In this state, the three ports P, T, K are located at the second position. The land 37 is opened, the hydraulic clutch E is disengaged, and the merging port Q is closed. At this time, due to the action of the pair of left and right return springs 33, 33, the shift fork 19 has a boss portion 19a fitted onto the first transmission shaft 13 in the center S of the region S surrounded by the pair of snap rings 34, 34. Located on the sleeve 2
3 is located within the right and left width of the synchronizer 22.

Switching from the Neutral Position to the Forward Position When the switching lever 40 in the neutral position N is operated toward the forward position F, the spool 17 is first slid by the relative slidable fitting structure of the spool 17 and the shift fork 19. The first valve body 38 closes the pump port P with a rightward stroke d1 (see FIG. 7B). And left return spring 3
Only the spool 17 moves to the right and the shift fork 19 does not move until 3 is compressed into a close contact state, that is, up to the stroke d2 (see FIG. 7C). In the d2 stroke state, the first valve body 38 is still located to the left of the supply / discharge port K, and the hydraulic clutch E is still in the disengaged state.

When the spool 17 moves rightward to the stroke d3, the communication between the second land 37 and the supply / discharge port K is blocked by the first valve body 38, and at this time, the shift fork 19 is moved by the distance (d3-d2). ) It is moving to the right, and the state in which the synchronous engagement operation of the sleeve 23 to the forward driven gear 20 has already started has started (see FIG. 7D).
Further, when the spool 17 moves further rightward from this state, the supply / discharge port K starts to open to the first land 36, and the pressure oil supply to the hydraulic clutch E is started.

When the spool 17 reaches the forward drive position F, the pump port P and the supply / discharge port K communicate with each other via the first land 36, and the supply / discharge port K and the tank port T are connected by the first valve body 38. Are separated from each other, the hydraulic clutch E is turned on, and the shift fork 19 is moved by the shift stroke L-d2 of the spool 17 to complete the gear engagement operation (see FIG. 7 (E)).

That is, when switching from the neutral position N to the forward position F, the gear meshing operation of the forward / reverse switching mechanism C is first performed while the hydraulic clutch E is disengaged, and then the hydraulic clutch E is engaged. The operation sequence is attached so that you can smoothly and lightly shift with less shock.
It should be noted that between the neutral position N and the forward position F, the merging port Q is closed.

Switching from the neutral position to the reverse position When the switching lever 40 at the neutral position N shown in FIG. 8A is operated toward the reverse position R, first, the right return spring 33 is compressed to be in a close contact state. Up to the stroke d2, only the spool 17 moves to the left, and the shift fork 19 does not move due to the compression deformation of the return spring 33 (see FIG. 8B). In the d2 stroke state, the second valve body 39 is still located on the right side of the tank port T, all the ports P, T, K are opened to the second land 37, and the hydraulic clutch E is continuously disengaged. It is in.

When the spool 17 moves leftward to the stroke d3, the second valve body 39 closes the tank port T and switches to the engaged state of the hydraulic clutch E. At this time, the shift fork 19 moves a distance (d3- d
2) It is moving to the left and the state in which the synchronous engagement of the sleeve 23 with the backward driven gear 21 has already started (see FIG. 8C). Also, the merging port Q starts to open before this state.

When the spool 17 reaches the reverse position R,
The pump port P and the supply / discharge port K communicate with each other via the second land 37, the first valve body 38 separates the supply / discharge port K and the tank port T, the hydraulic clutch E is engaged, and the shift fork is provided. 19 has moved L-d2, and the gear occlusal operation has been completed [see FIG. 8 (d)]. Therefore,
Even when the neutral position N is switched to the reverse position R, similarly to the switching to the forward position F, the gear meshing operation of the forward / reverse switching mechanism C is first performed with the hydraulic clutch E in the disengaged state, and then the hydraulic clutch E is switched. The order of operation is such that they are in the order.

Further, in the reverse drive state, the merging port Q also communicates with the pump port P via the second land 37, and as a result, the lift cylinder 8 is pressurized with the hydraulic oil of the lift control valve 44 by the reverse lift means 47. Then, the pressure oil of the clutch control valve V is merged, and the planting apparatus A is quickly raised.

Switching from Forward Position F to Neutral Position N From the forward position F state shown in FIG.
When the spool 17 is moved to the left by operating, the first valve body 38 closes the supply / discharge port K at the stroke d1 to end the pressure oil supply state (see FIG. 9B), and from this position. Moving further to the left, the supply / discharge port K and the tank port T
And are opened via the second land 37. At this time, the shift fork 19 has not moved yet and is in the forward movement state.

The shift fork 19 does not move until the stroke d2 at which the left return spring 33 returns to the free state, and only the spool 17 moves leftward. In this state, the first valve body 38 supplies the pump port P with the pump port P. The exhaust port K is partitioned, the supply / exhaust port K communicates with the tank port T, and the hydraulic clutch E is switched off (FIG. 9).
(See (c)). At this time, the boss portion 19a is located at the center position on the left and right of the region S.

When the spool 17 further moves to the left,
The shift fork 19 also starts to move, and the disengagement operation of the sleeve 23 and the driven gear 20 for forward movement is started. When the stroke L of the spool 17 moves, the boss portion 19a is moved.
Is located at the left and right center of the region S, and a completely non-occlusal state, that is, a neutral state shown in FIG.

At this time, even if the right return spring 33 is maximally compressed without the shift fork 19 moving due to the sliding resistance of the shift portion (see FIG. 9D), the spool 1
At the time of completion of the shift of No. 7, at least (L-2d2) strokes are forcibly moved, the disengagement operation of the gear bite is already started, the hydraulic clutch E is continuously disengaged, and the sleeve 23 is almost meshed. Pressure is not working. Therefore, the boss portion 19a is automatically returned to the left and right center of the region S by the returning biasing force of the compressed right return spring 33 from the compressed state to the free state.

That is, in switching from the forward drive position to the neutral position, the hydraulic clutch E is first disengaged when the shift fork 19 does not move, that is, when the forward drive gear 20 and the sleeve 23 are engaged. The operating sequence is arranged so that the meshing pressure is released and then the meshing disengagement operation of the gear is started. Therefore, it is possible to smoothly and lightly perform the shift operation with less shock caused by the disengagement of the gear.

Switching from the reverse position to the neutral position From the reverse position R state shown in FIG.
When 0 is operated to move the spool 17 to the right, first, the supply / discharge port K and the tank port P communicate with each other through the second land 37 up to the stroke d1, and the hydraulic clutch E is continuously engaged. The shift fork 19 still does not move (see FIG. 10B). When the spool 17 moves further rightward from this d1 stroke state, the second land 3
7 also starts to open to the tank port T, and the hydraulic clutch E is switched to the disengaged state.

The shift fork 19 does not move until the stroke d2 in which the right return spring 33 returns to the free state, and only the spool 17 moves to the right. In this state, the ports P, T, K is open and hydraulic clutch E is disengaged [Fig. 10 (c)]
reference〕. At this time, the boss portion 19a is located at the center position on the left and right of the region S.

When the spool 17 further moves to the right,
The shift fork 19 also starts to move, and the disengagement operation of the sleeve 23 and the backward driven gear 21 is started. When the stroke L of the spool 17 moves, the boss portion 19a is moved.
Is located at the left and right center of the region S, and a completely non-occlusal state, that is, a neutral state shown in FIG.

At this time, even when the shift return fork 19 is not moved due to the sliding resistance of the shift portion and the left return spring 33 is maximally compressed (see FIG. 10D), when the shift of the spool 17 is completed. Then, at least the stroke of (L-2d2) is forcibly moved, the disengagement operation of the gear engagement has already started, the hydraulic clutch E is still in the disengaged state, and the engagement pressure is almost applied to the sleeve 23. Absent. Therefore, similarly to when switching from the forward position to the neutral position, the boss portion 19a automatically returns to the left and right center of the region S by the biasing force of the compressed left return spring 33 from the compressed state to the free state. It will be.

Therefore, even when the reverse position is switched to the neutral position, the shift fork 19 does not move, that is, the reverse driven gear 21 and the sleeve 23 are engaged with each other, the hydraulic clutch E is first disengaged. The operating sequence is arranged so that the meshing pressure is released and then the meshing disengagement operation of the gear is started.

FIG. 7 (e) shows a forward state in which the switching lever 40 is operated to the forward position F and the spool 17 is pushed rightward (to the side of the control valve V). The pump port P and the supply / discharge port are shown. K communicates with each other through the first land 36, and the tank port T and the supply / discharge port K are separated by the first valve body 38, and the hydraulic clutch E is engaged. At this time, the left side (switching lever 40 side) return spring 33 is in a compressed and closely contacted state, and the shift fork 19 is at a position displaced to the left between the pair of snap rings 34, 34.

In the embodiment described above, the stroke d, which is the displacement amount between the spool 17 and the shift fork 19, is set.
2 corresponds to the accommodation U. Further, the switching lever 40, the spool 17, and the shift fork 19 constitute an artificial operation system M for manually shifting the sleeve 23, and the spool 17 and the shift fork 19 link the control valve V and the sleeve 23 together. A linked operation system J is configured.

As shown in FIGS. 12 to 14, the inter-main stock lever 51 of the three-stage inter-stock stock transmission mechanism (not shown) and the height 2
The inter-sub-stock stock lever 52 of the inter-sub-stock stock shift mechanism (not shown) is provided, and a display device H is provided which displays the inter-stock stock gear step that has appeared in association with the operating rods 51a and 52a. There is. That is, the display plate 53 indicating the distance between stocks and the sub arm 52b interlocked with the sub operation rod 52a are attached to the pivot shaft 54 in an integrally rotatable state, and the main arm 51b interlocked with the main operation rod 51a is attached. It is fitted to the rotary shaft 54 so as to be relatively rotatable, and the viewing windows 5 are provided at four locations.
A position-fixed window plate 55 on which 5a is formed is arranged immediately in front of the display plate 53.

That is, as shown in FIG. 12, when the lever 52 between subsidiary stocks is operated at a low speed, the display plate 53 is also rotated and the numbers 12, 16, neutral and 18 can be seen from the peep window 55a. When the main stock lever 51 is operated to, for example, the neutral position in this state, the end of the main arm 51b is located immediately above the observation window 55a through which "neutral" can be seen. Therefore, the number that can be seen through the peep window 55a located at the end of the main arm 51b is the stock interval (unit is cm), and the current stock interval can be easily recognized.

Further, for example, as shown in FIG. 13, when the end of the main arm 51b is located above the observation window 55a where "18" can be seen, the stock distance is set to 18 cm, that is, At this time, the inter-substock lever 52 is operated to the high speed position, and the main interstock lever 51 is operated to the second speed position.

[Other Embodiments] As shown in FIG. 15, the shift fork 19 is slidably fitted onto a dedicated fork shaft 41, and the operating piece 17a attached to the spool 17 and the shift fork 19 are interlocked and linked. The structure may be used. In this case, the engagement width w1 of the shift fork 19 is set to the operation piece 1
The accommodation U is formed by taking a width larger than the width w2 of 7a. However, in the structure of this another embodiment, the operation piece 17a is
Since the position of the shift fork 19 within the engaging width w1 is not determined, the shift fork 19 and the sleeve 2 are accommodated for that position.
It is necessary to have a margin for the engagement width with the gear No. 3, and it is necessary to make the shift stroke and the width of the synchronizer 22 larger than those of the present embodiment. In other words, the pair of springs 3
The structure of the present embodiment, which is urged to return by 3, 33, has an advantage that the forward / reverse switching mechanism C can be made compact while having the accommodation U for setting the operation sequence.

In each of the above-described two embodiments, the spool 17 is first moved by the switching lever 40, and the shift fork 19 is moved by the spool 17, as shown in FIG.
As shown in FIG. 6 and FIG. 17, a structure may be employed in which the switching lever 40 first operates the shift fork 19 and the shift fork 19 moves the spool 17. In this case, the shift fork 19 and the spool 17 are configured to move integrally without delay (for example, roll pin connection or screw fixing),
The interchange U is provided between the shift fork 19 and the sleeve 23. That is, the engagement width w1 of the sleeve 23 is made larger than the fork portion width w2 of the shift fork 19, and it is more preferable to provide a pair of return springs 33, 33.

The control valve V may be a rotary type having a rotary spool. Further, as shown in FIG. 18, the third valve body 4 having the same width as the first valve body 38 is provided at the center position between the first valve body 38 and the second valve body 39 of the spool 17.
2 may be formed into the spool 17 having the first to third lands 36, 37, 43, and the hydraulic clutch E may be engaged even in the neutral position N. Further, in addition to the forward / reverse switching mechanism, a main gear transmission mechanism or a sub gear transmission mechanism may be used, and these are generically defined as a gear transmission mechanism C.

As shown in FIG. 19, with the second valve body 39 lengthened, the right end of the spool 17 is extended to extend the third valve body 42.
And the third land 43 and the valve case 32.
To form a merging port Q with the second pump port P2. Then, the pump 50 for the power steering device (an example of another hydraulic actuator) 49 for the front wheels 1 is connected to the second pump port P2, and the merging port Q is connected to the lifting cylinder 8 via the check valve 48. But good. That is, when the switching lever 40 is operated to the reverse position R, the pressure oil of the pump 50 in the power steering hydraulic circuit Z is merged with the pressure oil of the lifting control valve 44 by the backward lifting means 47 in the lifting cylinder 8 to quickly move. The planting apparatus A is raised.

For example, the ground work device A in the tractor
It is also possible to consider a structure in which the ascending operation associated with the backward movement is merged with the hydraulic circuit of the lift cylinder for raising and lowering the mid mower (an example of another hydraulic actuator).

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of drawings]

FIG. 1 is a side view of a riding rice transplanter.

[Fig. 2] Development view of main parts of transmission system

FIG. 3 is a development view showing a forward / reverse switching mechanism and its operation structure.

FIG. 4 is a side view showing the structure of the control valve.

5 is a sectional view taken along the line aa of FIG. 4 showing the structure of the control valve.

6 is a cross-sectional view taken along the line bb of FIG. 4 showing the structure and oil passage of the control valve.

FIG. 7 is an operation diagram showing a switching operation from neutral to forward.

FIG. 8 is an operation diagram showing a switching operation from neutral to reverse.

FIG. 9 is an operation diagram showing a switching operation from forward to neutral.

FIG. 10 is an operation diagram showing a switching operation from reverse to neutral.

FIG. 11 is a system diagram showing a main part of a forward / reverse switching operation.

FIG. 12 is a display example diagram showing a display device for stock shifts.

FIG. 13 is a display example showing a display device for stock shift.

FIG. 14 is a side view showing the structure of the display device.

FIG. 15 is a diagram showing another structure 1 of forward / reverse switching operation.

FIG. 16 is a diagram showing another structure 2 for forward / reverse switching operation.

FIG. 17 is a diagram showing another structure 3 for forward / reverse switching operation.

FIG. 18 is a view showing a structure for each spool.

FIG. 19 is a system diagram showing another structure of backup operation.

[Explanation of symbols]

 8 Lifting hydraulic cylinder 23 Shifter 44 Lifting control valve A Working device C Gear shifting mechanism E Hydraulic clutch J Link operation system M Manipulation system U Flexible V Control valve Z Hydraulic circuit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location B60K 20/02 B60K 20/02 F

Claims (3)

[Claims] 1. A gear type traveling speed change mechanism (C), a hydraulic clutch (E) arranged on the transmission side of the transmission, a shifter (23) of the traveling speed change mechanism (C), and the shifter. (23) is provided with a manual operation system (M) for shifting by manual operation, and the shifter (23) is brought into an engaged state as the gear meshing position and the gear non-meshing position move from one to the other. A linkage operation system (J) is provided to interlock the clutch control valve (V) of the hydraulic clutch (E) and the shifter (23) so that the certain hydraulic clutch (E) is temporarily disengaged, And the shifter (2
3) In order to disengage and operate the hydraulic clutch (E) prior to the start of the shift of 3), the flexible operation (U) is provided in the interlocking portion of the manual operation system (M) or the linkage operation system (J), and The hydraulic oil supplied to the hydraulic clutch (E) due to the switching of the traveling speed change mechanism (C) to the reverse side is supplied to the working device (A) lifting hydraulic cylinder (8) connected to the rear part of the machine body. A shift operation device for an agricultural work machine, wherein the clutch control valve (V) and the hydraulic cylinder (8) are linked so that the work device (A) is raised by being guided. 2. The up-down control valve for switching the up-down control valve (44) of the hydraulic cylinder (8) to the up-side when the traveling speed change mechanism (C) is switched to the reverse side. The gear shift operating device for an agricultural working machine according to claim 1, wherein (44) and the manual operating system (M) are linked with each other. 3. A hydraulic actuator (4) other than the hydraulic clutch (E) and the hydraulic cylinder (8) in association with the switching of the traveling speed change mechanism (C) to the reverse side.
The hydraulic circuit (Z) of the hydraulic actuator (49) and the clutch control valve so that the hydraulic oil supplied to 9) is guided to the hydraulic cylinder (8) to raise the working device (A). (E) is linked with (1) or (2)
The gear shift operation device for an agricultural work machine described in.