JPH0134773Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shift operation mechanism for configuring a hydraulic transmission device such as a power transmission.

Conventionally, to construct the above-mentioned speed change operation mechanism, a groove for forming a flow path was bored in the wall surface of the transmission case, and a plate with operating valves, actuators, shift forks, etc. attached to the outer surface was pasted on the groove forming surface. However, these grooves were formed in flow paths that communicated and connected the operating valves, actuators, shift forks, etc. and each hydraulic device in the transmission case.

However, in this case, the wall of the transmission case body is used as part of the gear shift operation mechanism, and the operation valve, actuator, shift fork, etc. must be assembled from both sides of the wall, making assembly difficult. Not only did this require a lot of time, but it was also extremely difficult to maintain, as the transmission case itself had to be disassembled each time the transmission operation mechanism was broken or repaired.

In view of the above-mentioned conventional circumstances, an object of the present invention is to provide a shift operation mechanism that is easy to assemble and easy to inspect and maintain by rationally improving the plate and its mounting structure.

The characteristic configuration of the present invention is that an opening is formed in the case wall at the location where the shift fork is installed in the transmission case.
A lid is attached to the opening, and the lid includes:
The shift fork, a hydraulic operating device that switches and operates the shift fork using pressure oil, and an oil passage forming portion that supplies pressure oil to the hydraulic operating device, and the oil passage forming portion includes: The reason is that grooves that serve as oil passages are provided on the mating surfaces of the plurality of plates.

In other words, the oil passage forming section formed by a plurality of plates is made into an independent part separated from the transmission case body, and a shift fork for shifting and a hydraulic operating device for switching the shift fork using pressure oil are installed there. Since the gear shift operating device can be formed by integrating them together, and the integrated gear shifting operating device can be attached to the opening of the transmission case, ease of assembly is greatly improved. At the same time, it is also possible to provide the convenience of being able to perform inspection and maintenance by removing only the transmission operating device from the transmission case body.

In addition, in the conventional structure, the transmission case body is a part of the gear shift operating device, so it was impossible to inspect the operating state of the gear shift operating device alone, but with the present invention, this is not possible. Since inspection becomes possible, it also has the effect of being excellent in inspection properties.

Next, embodiments of the present invention will be described in detail based on illustrative drawings.

As shown in FIG. 1, power from the engine E is transmitted to the main transmission 1, hydraulic multi-disc clutch 2, auxiliary transmission 3, and super-deceleration switching device 4 in that order, and the super-deceleration switching device The power taken out from device 4,
A pair of left and right rear wheels 6 via a rear wheel differential device 5
In addition, the power is transmitted to a pair of left and right steering front wheels 9 via a transmission shaft 7 and a front wheel differential device 8. Then, the power branched from the transmission upper side of the main transmission 1 is transferred to the power extraction transmission 1.
0 and a hydraulic multi-plate clutch 11 to transmit the power to the working machine drive power take-off shaft 12;
It constitutes a drive device for a working vehicle such as a wheel-drive tractor.

As shown in FIGS. 1 and 2, each transmission device 1, 3, 4, 10 has a neutral position N
The driving system shift valve _V1 , which is configured as a rotary type 9-position N, _F1 to _F8 switching valve including The actuator 14 for high/low speed switching in 3 is integrally operated to produce a 4-speed shift in the main transmission 1 and a 2-speed shift in the auxiliary transmission 3, and the sliding 3-position NF, R The forward/reverse switching actuator 15 in the sub-transmission device 3 is operated by the forward/reverse switching valve V ₂ configured in the switching valve, and then,
It is configured to provide eight speeds in each of the forward and forward directions.

The super deceleration switching device 4 is operated by the mechanically operated shift device 16 to switch between the normal deceleration state and the super deceleration state, and
Similarly, a mechanically operated shift device 17 is configured to intermittent power transmission to the front wheel drive transmission shaft 7 to switch between a two-wheel drive state and a four-wheel drive state.

In addition, the power take-off system speed change valve _V3 , which is configured as a rotary type 5-position n, _f1 to _f4 switching valve including the neutral position n, controls two sets of speed change operation actuators 18a in the power take-off transmission 10. ,18
b is integrally operated to perform a four-speed power extraction system.

In addition, P in the figure is an operating pressure oil supply pump directly connected to the input shaft _S1 of the transmission case M.

When operating each of the clutches 2 and 11, the second
As shown in the figure, each actuator 13a,
13b, 14, 15, 18a, 18b in a state where the plunger 19 is also used as a sliding spool, and the actuators 13a, 13b, 1
six three-position switching valves x 1 to x 6 that block the flow of pressure oil from the corresponding valves V ₁ , V ₂ , and V ₃ only when 4, 15, 18 a, _{and 18 b} are in the neutral position;
Five two-position switching valves _y2 to _y6 each operated by pilot pressure from the three-position switching valves _x1 to _x6.
Of these, three drive system hydraulic clutches y ₂ , y ₃ , y ₄ operate the drive system hydraulic clutch 2, two power take-off system hydraulic clutches y ₅ , y ₆ operate the power take-off system hydraulic clutch 11, and each valve V ₁ ,V ₂ ,
Each gear is configured to operate automatically in conjunction with the _V3 's gear change operation.

In addition, 20 in the figure is a lubricating oil supply path for the clutches 2 and 11 which also serves as a relief valve 21 circuit for the pump P.

Next, the specific structure of the mission case M will be explained in detail with reference to FIGS. 3 and 4.

The transmission case M is a front transmission case part Ma that houses the main transmission 1, the power extraction transmission 10, and the clutches 2 and 11 of both systems.
, a sub-transmission device 3, a super-deceleration switching device 4, and
It is formed separately from the rear transmission case part Mb in which the 2WD/4WD switching device is installed, and also includes the traveling system valve V ₁ , the power extraction system valve V ₃ , the actuators 13a and 13b for the main transmission 1, and the power extraction transmission. Actuators 18a, 18b for the device 10 and
Those actuators 13a, 13b, 18a,
The two-position switching valves y ₃ , y ₄ , y ₅ , y ₆ for 18b, and the transmission operating device Ua, which is a front hydraulic operating unit equipped with the relief valve 21, are installed in an oil hole drilled in the mission case M. a, b, c, d, e
(corresponding to the reference numerals in Fig. 2) is installed in the opening ma of the side wall of the front transmission case part Ma in a state of communication and connection, and the forward/reverse switching valve
V ₂ , actuator 14, 15 for sub-transmission device 3
And, the rear hydraulic operation unit Ub equipped with the two-position switching valve _y2 for the high-low speed switching actuator 14 is installed in the opening in the side wall of the rear transmission case part Mb in a state where it is also connected to the drilled oil hole. be.

To explain the structure of the speed change operation device Ua in more detail, the main speed change device 1 and the power transmission speed change device 1 are mounted on both sides of the relatively thick intermediate plate 22.
0 four actuators 13a, 13b, 18
A plurality of grooves 23 for forming each oil passage in the a and 18b systems are bored at appropriate locations in a state where they are appropriately connected to each other on both sides, and the grooves 23 are
Oil holes a to e are drilled on the transmission case side in a part of the
An inner plate 24 having holes 24a for communicating with the above-mentioned valves and actuators is formed on the inner surface of the intermediate plate 22, and an outer side plate 24 having a number of holes 25a for appropriately communicating the grooves 23 with the valves and actuators. The plates 25 are attached to the outer surface of the intermediate plate 22 with an adhesive applied to the entire surface other than the groove 23 portion, and the grooves 23 are formed in each oil passage in the hydraulic operation circuit. It is in Kb. And the valves V ₁ ,
A hydraulic operating device Kb consisting of V ₃ , y ₃ , y ₄ , y ₅ , y ₆ , 21 and actuators 13a, 13b, 18a, 18b is attached to the outer surface of the outer plate 25, and each actuator 13a, 13b is attached to the outer surface of the outer plate 25. ,18
Shift fork 26 attached to a and 18b
The transmission operating device Ua is formed by integrally attaching the two plates 22, 24, and 25 so as to protrude into the transmission case M from a square hole 27 that communicates with the plates 22, 24, and 25. Then, the entire state in which the speed change operation device Ua is attached to the front transmission case portion Ma to serve as a lid for the opening portion ma is sealed with a cover Mc to form a lid F. Further, the space inside the cover Mc, which communicates with the inside of the mission case M through the square hole 27, is configured to also serve as a drain space for the valves and actuators.

In addition, f, g, h, i and f', g', h', i' in the figure are
This is an oil hole drilled to connect the speed change operating device Ua and the rear hydraulic operating unit Ub, and corresponds to the reference numerals in FIG. 2.

The specific shape of each plate 22, 24, 25 and the specific arrangement of the grooves 23 formed on both sides of the intermediate plate 22 can be changed in various ways. The pasting structure of 24 and 25 is also replaced with adhesive, and the groove 23
Various configuration changes are possible, such as bolt connection with a gasket interposed on the entire surface other than the forming part.

The present invention is directed to a speed change operating mechanism for forming a speed change device included in various equipment such as agricultural and construction equipment.

Note that although reference numerals are written in the claims section of the utility model registration for convenience of comparison with the drawings, the present invention is not limited to the structure of the attached drawings by such entry.

[Brief explanation of drawings]

The drawings illustrate an embodiment of the speed change operation mechanism according to the present invention, FIG. 1 is an overall schematic plan view showing the drive structure of a working vehicle, FIG. 2 is a hydraulic operation circuit diagram, and FIG. 3 is a speed change operation mechanism. FIG. 4 is an exploded perspective view showing the structure of the gear shift operating mechanism. M...Mission case, ma...Opening, F...
...Lid, 26...Shift fork, Ka...Oil passage forming part, Kb...Hydraulic operating device.

Claims (1)

[Scope of utility model registration request] An opening ma is formed in the case wall at the location where the shift fork 26 of the transmission case M is disposed, and the opening ma
At the same time, a lid F is attached to the lid F, and the shift fork 26 and the shift fork 26 are attached to the lid F.
a hydraulic operating device Kb that switches and operates the hydraulic operating device Kb using pressure oil, and an oil passage forming section Ka that supplies pressure oil to the hydraulic operating device Kb.
and the oil passage forming part Ka is
A gear shifting operation mechanism characterized by having grooves that serve as oil passages on the mating surfaces of a plurality of plates.