JPH0356767A - Hydraulic clutch construction for transmission - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a pressure oil supply path to a hydraulic clutch installed in a transmission system to switch the oil supply to the hydraulic clutch and the oil drainage state from the hydraulic clutch. A hydraulic clutch structure for shifting, comprising a switching valve and an accumulator for accumulating pressure oil to the hydraulic clutch, and the accumulator is provided in a path between the hydraulic clutch and the switching valve, By providing an accumulator in the path between the switching valve and the hydraulic clutch, the pressure oil in the accumulator can be drained more quickly than the switching valve, and then oil is supplied to the hydraulic clutch. The present invention relates to a hydraulic clutch structure for shifting, which allows an accumulator to act from zero pressure when shifting, exhibits the desired ability as an accumulator, and contributes to alleviating shift shock.

[Prior Art] Conventionally, hydraulic equipment such as this type of accumulator is attached to a transmission case and connected to the hydraulic clutch through a pipe extending to the hydraulic clutch.

[Problem to be solved by the invention]

Therefore, since piping is required to connect this hydraulic clutch and the accumulator, it is necessary to secure installation space for this piping, and there is room for improvement in terms of production and cost since the piping itself is required as a component. is left behind, and
There was a point that the supply/discharge resistance to the hydraulic clutch became correspondingly large.

An object of the present invention is to provide a device that can solve the conventional drawbacks by rationally selecting the mounting position of the accumulator.

[Means to solve the problem]

A feature of claim 1 is that the accumulator is formed on a fixed boss that is fitted onto the clutch case boss of the hydraulic clutch and forms a rotary joint for taking in clutch hydraulic oil, Another feature of the invention is that the accumulator is provided in a clutch case of the hydraulic clutch, and a feature of the invention is that the accumulator is provided in a pressure oil supply space of a clutch case of the hydraulic clutch. The functions and effects of each are as follows.

[Effect according to claim 1] The hydraulic oil input to the rotary joint enters the accumulator and is accumulated in pressure, and flows from the accumulator into the pressure oil supply chamber of the hydraulic clutch, causing a slow increase in the hydraulic clutch pressure. appear.

[Effect of claim l]

Therefore, the piping from the accumulator to the hydraulic clutch, which was required in the past, can be omitted, and design constraints such as securing installation space for piping can be removed, and the piping leading to the hydraulic clutch can be eliminated. Resistance can also be reduced.

Furthermore, since the accumulator is installed at the fixed boss portion of the rotary joint, dead space can be used effectively. That is, since this boss portion originally has a diameter smaller than the outer diameter of the clutch case of the hydraulic clutch as shown in the figure, the outside of the fixed boss is an empty space. Therefore, by providing the accumulator on the fixed boss, the accumulator can be fitted into the empty space, and the dead space can be used effectively.

[Effect of Claim 2] In this case, the pressure oil supplied to the rotary joint is supplied to the pressure oil supply space of the clutch case, and from this pressure oil supply space is also supplied to the accumulator at the same time. A gradual pressure increase in the hydraulic clutch appears.

[Effect of Claim 2] Therefore, in this case as well, the piping from the accumulator to the hydraulic clutch can be omitted, and as shown in FIG. It is also possible to provide a protruding layer.

[Effect according to claim 3] 1. An accumulator is provided in the hydraulic clutch case.
As an example, as shown in FIG.
) is the friction plate (16a). Since the small-diameter piston (18B) is allowed to move further while in contact with (17a), the piston (18B) on the small diameter side is able to move further, so that the piston (18B) has a large At the initial engagement point when the radial piston (18A) contacts the friction plate (17a) and becomes a half-clutch state, it is possible to suppress the sudden rise in clutch pressure as shown in Fig. 4 (I). can.

[Effect of Claim 3] Although an example in which the piston is deformed has been shown as an example of a configuration in which an accumulator is provided in the hydraulic clutch case, the pressure oil supply space in the clutch case has a large volume. Therefore, a dedicated accumulator room can be provided.

Therefore, by providing an accumulator within the hydraulic clutch case, piping from the accumulator to the hydraulic clutch can be omitted.

By providing the accumulator within the clutch case, there is no need to make the clutch case particularly large, and there is no need to provide a dedicated installation location for the accumulator outside the clutch case.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in Fig. 6, the power from the engine (1) is transmitted through the main clutch (2) to the main transmission (A), the multi-disc hydraulic clutch (B), the forward/reverse switching device (C), and the auxiliary transmission. Gearbox (
D) and the super reduction gear (E), and transmits the shifting power to the differential gear (3a) of each of the front and rear wheels (3), (4).
．． (4a), and a working transmission system is formed to transmit the power from the main clutch (2) to the external power output shaft (6) via the transmission mechanism (5). This constitutes the drive system of a four-wheel drive agricultural tractor.

The main transmission (A) is a two-synchromesh type gear transmission mechanism, and is capable of shifting into four stages, and the forward/reverse switching device (C) and the sub-transmission (D) are both synchromesh-type gear transmission mechanisms. The main transmission (A) is composed of two hydraulic cylinders (T+), (T,), and the auxiliary transmission (D
) are configured to change gears with a single hydraulic cylinder (T, ), and the forward/reverse switching device (C) is configured to change gears manually.Furthermore, in this agricultural tractor, these three types When a gear shifting operation is performed, the hydraulic clutch (B) is disengaged at the start of the gear shifting operation, and the hydraulic clutch (B) is engaged and operated at the completion of the gear shifting operation, thereby disengaging the main clutch (2). It is equipped with a hydraulic control system to change gears without having to do so.

That is, the hydraulic control system is configured as shown in FIG. mechanism(
F) and a pilot pressure-operated switching valve (9), and the three hydraulic cylinders (TI), (
A rotary type speed change control valve (10) for controlling T2) and (T3), and a pilot oil passage (1l) for obtaining pilot pressure for operating the switching valve (9) are branched. , the hydraulic cylinder (TI), (T2). (
T3) and the operating system of the forward/reverse switching device (C) are each linked with an open/close operation type check valve (12). During a gear shift operation, the switching valve ( 9) to operate the hydraulic clutch (B) on and off as described above.

Incidentally, the pressure regulating mechanism (F) suppresses a sudden increase in clutch pressure when the switching valve (9) is turned on,
The clutch pressure is configured to increase with predetermined characteristics.

Next, the hydraulic clutch (B) will be explained.

As shown in Figure 1, the output shaft (13
) A transmission member (l4) having a substantially doglegged cross section is spline-fitted to the shaft end of the shaft, and a clutch body (16) is spline-fitted to the end of the human-powered shaft (15) of the forward/reverse switching device (C). The case (17) is supported by a bearing. Friction plate belonging to the clutch case (17) (
17a) and the friction plate (16a) belonging to the clutch body (16) are provided, and the piston (18) is moved by a spring (24) to the friction plate (16).
a), (17a), and pressurized oil pushes the piston (18) against the friction plates (16a.
), (17a). on the other hand,
The piston (1) is inserted between the friction plates (16a) and (17a).
8) Arrange the flange portion (14a) of the transmission member (14) on the side opposite to the existing side, and attach the snap ring (19) that receives the flange portion (14a) to the clutch case (
17) is installed. Therefore, the piston (l
8> is pressed against the friction plates (16a), (17a), the flange portion (14a>) is pressed against the friction plates (16a), (17a).
(17a), and power is transmitted from the transmission member (13) to the clutch body (16).

Next, a structure for supplying pressure oil to the hydraulic clutch (B) will be explained. A boss (15) extends horizontally of the clutch case (17) and is pivotally supported by a bearing on the manpower shaft (15).
This boss (17A) forms an oil passage (20) that takes in pressure oil and supplies and discharges it to the back side of the piston.
A fixed boss (21) is fitted around the boss (17A) so as to be relatively rotatable, and an oil passage (21) communicating with the oil passage (20) is attached to this boss (17A).
20) and both bosses (17A). (21) forms a rotating joint (22). The fixed boss (
A cylindrical case (23A) is integrally formed on the outer peripheral surface of the cylindrical case (23A), and a spring and a piston are built in the cylindrical case (23A) to form an accumulator (23), and the pilot-operated switching valve (9) The control oil from the rotary join} (2
2), part of the oil that enters the hydraulic clutch (B) is stored in the accumulator (23) to alleviate the shift shock. Further, the accumulator (23) can be directly connected to the hydraulic clutch (B), and the piping between them can be omitted, and the oil drained from the accumulator (23) can be quickly drained through the switching valve (9).

[Another example]

■ The clutch case (1) is located outside the fixed boss (21).
A cylindrical case (23A) is formed on the lateral side of 7), and a piston and a spring are housed in this case (23A) to constitute an accumulator (23). This accumulator (2
The oil supply and drainage path (20) for the clutch case (3) is connected to the clutch case (
17) is in communication with the pressure oil supply space.

■ As shown in Figure 3, the piston (l8) is divided into a large diameter piston (18A) and a small diameter piston (18B), and the large diameter piston (18A) is divided into a small diameter piston (1
8B) on the outer peripheral surface of both (18A) within a certain range.
), (18B) are configured to allow relative movement in the axial direction. Here, the small diameter side piston (18B
) against both pistons (18A), (18B) and the friction plate (17a). (16a) The spring (24) that biases the larger diameter side piston (18A)
and the small diameter piston (19B), both (18A),
(i8B) in the direction of separating them (2)
5) is provided. When pressure oil is supplied from the rotary joint (22), the pressure increases against the spring (25), and first, the large diameter piston (18A) comes into contact with the friction plates (16a) and (17a). Furthermore, when the pressure increases, the small diameter piston (18B) resists the force of the spring (24).
moves relative to the larger diameter piston (18A).

Therefore, as shown by point (a) in the graph of FIG. 4(a), the sudden rise in pressure is alleviated by the relative movement of the small diameter side piston (18B) at the time of initial meeting. Then, when the supply pressure increases further, both pistons (18A). (18B
) work together to create a perfect joint condition.

(2) The structure of the hydraulic clutch may be applied to other agricultural machinery or general vehicles.

Incidentally, although reference numerals are written in the claims section for convenience of reference to the drawings, the present invention is not limited to the structure shown in the accompanying drawings by such entry.

[Brief explanation of drawings]

The drawings show an embodiment of the hydraulic clutch structure for speed change according to the present invention, FIG. 1 is a sectional view of the hydraulic clutch, FIG. 2 is a sectional view showing another embodiment of the accumulator mounting position, and FIG. 3 is a sectional view of another embodiment of the accumulator. A cross-sectional view showing an embodiment, Fig. 4 (a) is a hydraulic clutch pressure increase characteristic diagram when the accumulator shown in Fig. 3 is provided, and Fig. 4 (b) is a hydraulic clutch pressure rise characteristic when the accumulator shown in Fig. 3 is not provided. A characteristic diagram, FIG. 5 is a hydraulic configuration diagram, and FIG. 6 is a speed change configuration diagram. (B)...Hydraulic clutch, (9)...
Switching valve, (17)...Clutch case, (23
)...Akyumu Yu, (22)...
Rotating joint, (21)...Fixed boss.

Claims (1)

[Claims] 1. Switching the oil supply to the hydraulic clutch (B) and the oil draining state from the hydraulic clutch (B) to the pressure oil supply path to the hydraulic clutch (B) installed in the transmission system. Switching valve (9)
and an accumulator (23) for accumulating pressure oil for the hydraulic clutch (B), and the accumulator (23) is provided in a path between the hydraulic clutch (B) and the switching valve (9). A fixed boss (21) which is fitted onto the clutch case boss (17A) of the hydraulic clutch (B) and forms a rotary joint (22) for intake of clutch hydraulic oil, in the hydraulic clutch structure for shifting provided.
and a hydraulic clutch structure for shifting, in which the accumulator (23) is formed. 2. A switching valve (9) for switching oil supply to the hydraulic clutch (B) and oil draining state from the hydraulic clutch (B) is provided in the pressure oil supply path to the hydraulic clutch (B) installed in the transmission system.
and an accumulator (23) for accumulating pressure oil for the hydraulic clutch (B), and the accumulator (23) is provided in a path between the hydraulic clutch (B) and the switching valve (9). A hydraulic clutch structure for shifting, wherein the accumulator (23) is provided in a clutch case (17) of the hydraulic clutch (B). 3. A switching valve (9) for switching oil supply to the hydraulic clutch (B) and oil draining state from the hydraulic clutch (B) in the pressure oil supply path to the hydraulic clutch (B) installed in the transmission system.
and an accumulator (23) for accumulating pressure oil for the hydraulic clutch (B), and the accumulator (23) is provided in a path between the hydraulic clutch (B) and the switching valve (9). A hydraulic clutch structure for shifting, wherein the accumulator (23) is provided in a pressure oil supply space of a clutch case (17) in the hydraulic clutch (B).