JPS6343034A - Hydraulic actuator - Google Patents

Abstract

PURPOSE:To approach the optimum pressure for the clutch operation and reliably perform the clutch engagement operation by setting the pressure of the operating oil applied to a pressure plate via a regulating valve to the highest pressure or less of an oil pump. CONSTITUTION:Lubricating oil is pressurized by an oil pump 37 and is fed to a clutch mechanism 9 via a regulating valve 40 as the operating oil. When a clutch is to be engaged, friction plates 19, 20 are clamped and pressed by the support section 12c of a clutch center 12 and the press section 13b of a pressure plate 13 due to a clutch spring 29 to become a half-clutch state. Next, since a lifter plate 26 is energized to be removed from the clutch center 12, the plate 13 is pressed to the clutch center 12 by the operating oil fed into a hydraulic chamber 22, the pressing force of the friction plates 19, 20 is increased, and the power is transmitted from a clutch outer 11 to the clutch center 12.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to clutches used in vehicles and the like, and particularly to a hydraulic clutch that uses hydraulic pressure for engaging and engaging operations.

"Conventional technology" Conventionally, as one of the clutches used in vehicles,
A so-called hydraulic clutch is known, which uses hydraulic pressure generated by a prime mover installed in a vehicle as auxiliary power when performing the intermittent operation. No. 59-200818 is mentioned.

This technology consists of a clutch center that is integrally provided with a main shaft (rotation transmission shaft), a clutch outer that is attached to the main shaft so as to be relatively rotatable and is arranged to face the clutch center, and Each of the clutch center and clutch outer is provided with a number of friction plates that are movable along the length direction of the main shaft, and the friction plates attached to the club clutch outer are alternately arranged between the friction plates attached to the clutch center. By arranging the friction plates facing each other, and moving the friction plates in the length direction of the main shaft by hydraulic pressure to a position facing the friction plates, the friction plates are pressed against each other.
A pressure plate connecting the clutch center and the club tire outer is provided, a hydraulic chamber is formed surrounding the pressure plate, and a hydraulic oil control device for moving the pressure plate is connected to the hydraulic chamber. It has become.

On the other hand, the hydraulic oil control device connected to the hydraulic chamber is a first
As shown in the figure, an oil pump l and an oil pump I
a hydraulic oil supply path 4 that communicates between the hydraulic oil chamber 3 and the hydraulic chamber 3 of the clutch mechanism 2; and a fixed orifice installed in the middle of the hydraulic oil supply path 4 to limit the amount of hydraulic oil flowing into the hydraulic chamber 3. 5
and lubricating oil provided between the fixed orifice 5 and the oil pump I and sent to the sliding part of the prime mover (path shown) (a part of this will be used as the hydraulic oil, and from now on, the lubricating oil will be used as the sliding part) a relief valve 6 that sets the maximum pressure of the oil (the amount supplied to the hydraulic chamber 3 is used as lubricating oil, and the amount sent to the hydraulic chamber 3 is used as hydraulic oil), and a clutch operating mechanism that is connected to the hydraulic chamber 3. The structure is provided with a hydraulic oil discharge valve 7 that is opened and closed by.

In the conventional hydraulic clutch configured in this way, the hydraulic oil discharge valve 7 is kept in a closed state, and a portion of the lubricating oil supplied to each sliding part of the prime mover by the oil pump l is discharged from the hydraulic oil. is sent into the hydraulic chamber 3, and the pressure moves the Brennyer plate toward the friction plate.
As a result, the friction plates are brought into pressure contact with each other, and the clutch outer and the clutch center are connected via these friction plates, and the hydraulic oil discharge valve 7 is opened by the clutch operation mechanism to drain the hydraulic fluid into the hydraulic chamber. By discharging the hydraulic fluid No. 3, the pressing force exerted by the pressure plate on the friction plate is released, and the connection between the clutch outer and the clutch center is released.

"Problems to be Solved by the Invention" The present invention solves the problems that remain in the conventional technology described above.
The aim is to improve the following points.

That is, in the above-mentioned hydraulic clutch, a part of the lubricating oil sent from the oil pump I is used as hydraulic oil, and this hydraulic oil is sent directly from the oil pump I to the hydraulic chamber 3. The pressure P5 of the hydraulic oil acting on the pressure plate is maintained equal to the pressure PJ of the lubricating oil sent to the sliding parts of the prime mover,
As a result, as shown by curve A in Fig. 2, the pressure is much higher than the optimum pressure change (curve B in Fig. 2) for effectively carrying out the clutch engagement operation. It is.

Further, the control by the hydraulic oil control device adjusts the flow rate (opening degree adjustment) of the hydraulic oil discharge valve 7 with respect to the fixed orifice 5, so that the lubricating oil discharged from the oil pump 1 and the hydraulic oil in the hydraulic chamber 3 are controlled. This is done by changing the pressure ratio α (Pg/P,) as shown in FIG. That is, as the opening degree of the hydraulic oil discharge valve 7 is increased, the pressure Ps of the hydraulic oil acting on the pressure plate increases.
This reduces the joining force between the club tear outer and the clutch center.

However, even if the pressure ratio α is held constant, the rotational speed Ne of the prime mover is in a relatively low range, and the pressure P of the lubricating oil discharged from the oil pump I is in the process of increasing or decreasing. In the process, as the pressure PJ of the lubricating oil changes, the pressure Ps of the hydraulic oil in the hydraulic chamber 3 is also changed, and the above-mentioned joining force between the clutch outer and the clutch center is varied. The point is to put it away.

"Means for Solving the Problems" The present invention aims to provide a hydraulic clutch that can effectively solve the above-mentioned problems that should be improved. a clutch outer rotatably provided relative to the clutch center; a friction plate that engages only the clutch center; a friction plate that engages only the clutch outer; and a friction plate that engages only the clutch outer; A pressure plate that is moved by hydraulic pressure and presses the friction plates to engage and disengage the clutch center and the clutch outer via the friction plates, and controls the hydraulic pressure applied to the pressure plate. a hydraulic oil control device for pressurizing the hydraulic oil; a hydraulic oil supply path that communicates between the oil pump and the brake plate; It is characterized by comprising a relief valve provided in the middle of the oil supply path, and a pressure regulating valve provided between the relief valve and the pressure plate.

"Operation" The hydraulic clutch according to the present invention uses a pressure regulating valve provided after the relief valve to lower the pressure of the hydraulic oil applied to the pressure plate to a level equal to or lower than the maximum pressure generated by the oil pump. This is to bring the pressure of the hydraulic oil closer to the optimal pressure for performing the clutch engagement operation, and to suppress fluctuations in the hydraulic oil pressure in the area where the clutch engagement operation is performed.

"Example" An embodiment of the present invention will be described below with reference to FIG.

In FIG. 4, reference numeral 8 indicates the hydraulic clutch of this embodiment,
It includes a clutch mechanism 9 and a hydraulic oil control device 10 that controls the pressure of hydraulic oil supplied to the clutch mechanism 9.

The clutch mechanism 9 includes a clutch outer 11, a clutch center 12 that is rotatably provided relative to the clutch outer 11, and a clutch center 12 that is movable in the rotation axis direction of the clutch center 12 and the clutch outer 11. , a pressure plate 13 that is moved by hydraulic pressure to engage and disengage the clutch outer 11 and the clutch center 12.

To explain these details, the clutch outer 11 is in a state in which relative movement in the longitudinal direction of the main shaft 14 is restrained by a connecting pin 17 to a driven gear 16 attached to the main shaft 14 via a bearing I5. When the driven gear 16 is rotationally driven by the drive gear of the prime mover, the driven gear 16 and the driven gear 16 are rotated together.

Second, the clutch outer 11 and the driven gear 16 are capable of relative rotation by a predetermined angle in their rotational directions, and under normal conditions, the clutch outer 11 and the driven gear 16 are rotated by the elastic force of a damper spring 18 interposed between them. , relative position is regulated. Further, a cylindrical portion 1 is provided on the opposite side of the clutch outer 11 to the side to which the driven gear 16 is attached.
1a is formed, and a plurality of annular friction plates 19 are attached to the inside of the cylindrical portion ILa at intervals in the length direction of the main shaft 14 and concentrically with the clutch outer 11. .

These friction plates 19 are slidably engaged with a plurality of engagement grooves 11b formed along the length direction of the main shaft 14 in the cylindrical portion ILa of the face-shaped lazodia outer 11, and thereby, With respect to the clutch outer 11,
It is attached to the clutch outer 11 in a state in which relative movement in the rotational direction is restricted and movement along the length direction of the main shaft 14 is allowed.

The clutch center 12 is fixed to one end of the main shaft 14 with a space between it and the clutch outer 11, and on the side facing the club outer 11, there is a cylindrical portion +1a of the clutch outer 1■. A cylindrical portion 12a is formed to form a gap along the entire circumference between the cylindrical portion 12a and the inner circumferential surface. Further, a plurality of friction plates 20 are attached to the outside of the cylindrical portion 12a, and are inserted between the plurality of friction plates I9 attached to the cylindrical portion 11a of the clutch outer 11. , is slidably engaged with a locking IMI2b formed along the length direction of the main shaft 14 on the outer surface of the cylindrical portion 12a of the clutch center I2, so that it can rotate integrally with the clutch center 12, and The main shaft 14 is relatively movable along the length direction.Furthermore, a support 1112c parallel to the friction plate 20 is integrally formed on the outer periphery of the clutch center 12.

The pressure plate 13 is disposed between the clutch outer 11 and the clutch center 12, and is slidably fitted into the boss portion 12d of the clutch center 12 along the length direction of the main shaft 14. The sliding portion is held in a liquid-tight state by a sealing member 21 attached to the outer periphery of the boss portion 12d. Finally, four parts 13a are formed along the sliding direction of the pressure plate 13 at the center of the pressure plate 13 on the side facing the clutch outer 11, and the recessed part 13a
A hydraulic chamber 22 is formed by a backup plate 21a that is slidably and fluid-tightly fitted therein. Furthermore, a pressing portion 13b is integrally formed on the outer peripheral portion of the pressure plate 13, and is opposed to the support portion 12c of the clutch center 12 with the friction plates 19 and 20 interposed therebetween.
When the clutch center 12 is moved toward the clutch center 12, the friction plates 19 and 20 are held between the support portion 12c and pressed against the friction plates 19 and 20.

A protrusion 23 that penetrates the rim of the clutch center 12 is provided on the clutch center 12 side of the pressure plate 13.
24 are integrally protruded, and one of the protrusions 23 has a through hole 1 in its center that communicates with the hydraulic chamber 22.
3c, which is opened and closed by a reed valve 25 installed inside the hydraulic chamber 22. Further, the other protrusion 24 is disposed so as to be movable relative to the clutch center 12 in the longitudinal direction of the main shaft 14, and is slidably fitted into the lid plate 26. The lifter plate 26 and the pressure plate 13 are slidably connected by screwing a bolt 27 provided through the lifter plate 26 to the pressure plate 13.

An annular stopper 28 is disposed on the opposite side of the lifter plate 26 from the clutch center 12.
The stopper 28 is fixed to the pressure plate 13 by a bolt 27 provided through the lifter plate 26, and prevents the lifter plate 26 from coming off by coming into contact with the lifter plate 26. It looks like this. Further, a clutch spring 29 such as a disc spring is interposed between the stopper 28 and the clutch center 12, and the clutch spring 29 uses the clutch center 12 as a support and supports the lifter plate 26 as a clutch center. 12, the pressure plate 1 is fixed to the lifter plate 26.
3 toward the clutch center 2.

On the other hand, a control spring 3o is interposed between the pressure plate 13 and the lifter plate 26, surrounding the bolt 27 (protrusion 24).
The control spring 3o is set to have an elastic force that is weaker than the elastic force of the clutch spring 29, and elastically moves the lifter plate 26 away from the pressure plate 13 using the pressure plate 13 as a support. The projection 24 of the pressure plate 13 is brought into contact with the stopper 28 .
A predetermined gap G is formed between the lifter plate 26 and the lifter plate 26.

Further, a portion of the lifter plate 26 facing one of the protrusions 23 of the pressure plate 13 is loosely fitted into a through hole 13c formed in the protrusion 23 so as to face the reed valve 25. A control pin 31 is integrally provided.゛The control pin 31 constitutes a hydraulic oil discharge valve together with the reed valve 25, and when the lifter plate 26 is locked in a position where the above-mentioned gap G is formed between the lifter plate 26 and the pressure plate 13. In other words, when the lifter plate 26 is most spaced apart from the pressure plate 13, a small distance is formed between the lifter plate 26 and the reed valve 25, so that the reed valve 25 is closed, and the lifter plate 26 is brought closer to the pressure plate 13. When the reed valve 25 is moved, the reed valve 25 is gradually opened and suppressed according to the amount of movement, and the opening degree of the reed valve 25 is adjusted.

Further, the lifter plate 26 is rotatably supported via a bearing 34 by a suppressing member 33 that is attached to the casing 32 of the prime mover coaxially with the main shaft I4 and slidably in the longitudinal direction thereof. There is.

The suppressing member 33 is a cam shaft 35a of a camshaft 35 provided in the casing 32 orthogonally to the main shaft 14.
is brought into contact with the camshaft 35, and as the camshaft 35 rotates,
The main shaft 14 is reciprocated in the longitudinal direction, thereby allowing the lifter plate 26 to approach and separate from the brainer plate 13.

The camshaft 35 projects outside the casing 32, and has an operating lever 36 attached to its projecting end, and is connected to the operating lever 36 by a clutch wire (not shown). It is designed to be rotated back and forth within a predetermined angular range.

- The hydraulic oil control device IO includes an oil pump 37 driven by a prime mover, a hydraulic oil supply path 38 that communicates between the oil pump 37 and the hydraulic chamber 22 of the clutch mechanism 9, and the hydraulic oil supply path 38. a relief valve 39 provided on the downstream side of the oil pump 37 in the middle of the hydraulic oil supply path 38; a pressure regulating valve 40 provided between the relief valve 39 and the hydraulic chamber 22 in the middle of the hydraulic oil supply path 38; It is composed of a discharge valve (reed valve 25 and control pin 31).

The hydraulic oil supply path 38 includes a feed vibe 41 inserted into the main shaft 14 and a through hole 42 formed through the main shaft 14 in the radial direction.
, and a communication passage 43 formed between the pressure plate 13 and the backup plate 21a, and a communication passage 43 formed within the wall of the casing 32 and the oil pump 3.
7 and the pressure regulating valve 40, and a communication channel 41b formed in the wall of the casing 32 and communicating the feed vibe 39 and the pressure regulating valve 40. Main shaft 1
A fixed orifice 44 that limits the amount of hydraulic oil supplied into the feed vibe 41 is provided at the end that projects outward from the feed vibe 41 .

The relief valve 39 controls the pressure of the lubricating oil discharged from the oil pump 37 to be equal to or lower than a set value, and a portion of the lubricating oil discharged from the relief valve 39 is supplied to the pressure regulating valve as hydraulic oil. It is sent to the clutch mechanism 9 via 40.

In this embodiment, the pressure regulating valve 40 is a two-boat type reducing valve, and includes a body 45, a pressure regulating piston 46 slidably fitted into the body 45,
When the pressure regulating piston 46 is energized, the pressure regulating spring 4 sets the pressure of the hydraulic oil discharged from the pressure regulating valve 40.
7 and 0.

In this embodiment, the body 45 is formed of surface description connecting paths 41a and 4.
1b is fitted into the casing 32 in which the connecting passages 41a and 41b are formed, thereby forming two fire chambers 48 which are communicated with these communication passages 41a and 41b. An inlet 45a is formed which communicates with the oil pump 37 through a communication passage 41b, and an outlet 45b which communicates with the fixed orifice 44 through a communication passage 41b.
Further, the pressure regulating piston 46 has an inlet 045a and an outlet 4 formed in the body 45 by being overlapped with the inlet 45a as it moves relative to the body 45.
A communication hole 46a that communicates with 5b is formed.

In this pressure regulating valve 40, as the pressure within the second fire chamber 48 increases, the pressure regulating piston 46 is moved against the elastic force of the pressure regulating spring 47, and the pressure increases.
Maximum hydraulic oil pressure P required for clutch connection operation. At the point when the inlet 45a of the body 45 is closed,
As shown by the broken line C in FIG. 2, the hydraulic oil supplied to the clutch mechanism 9 is maintained at the pressure P.

It is designed to be held in place.

Further, in this embodiment, the pressure P. The rotation range of the prime mover in which this is generated is matched with the rotation range in which the clutch mechanism 9 starts to engage.

The operation of the hydraulic club bench 80 of this embodiment configured as described above will be explained as follows.

When the prime mover starts, lubricating oil is pressurized by the oil pump 37, and is supplied from the oil pump 37 to each sliding part of the prime mover via the relief valve 39, and also to the clutch mechanism 9 via the pressure regulating valve 40. Supplied as hydraulic oil.

Here, when the clutch is in a connected state (when no external force is applied to the suppressing portion (433)), the clutch spring 29 springs the stopper 28 in the direction away from the clutch center 12, and the clutch spring 29 The tire plate 13 is ejected toward the clutch center 12, and each friction plate 19, 20 is moved toward the support portion 12c of the clutch center 2 and the suppression portion 13b of the pressure plate 13.
The clutch outer 11 and the clutch center 12 are connected by the elastic force of the clutch spring 29 by being sandwiched and crimped by the clutch springs 29 and 29. Here, since the clutch spring 29 cannot sufficiently support the power transmitted between the clutch outer 11 and the clutch center 12, the crimp-like deafness caused only by the clutch spring 29 is a so-called half-clutch state. be. Further, the lifter plate 26 is connected to the control spring 3.
0 in the direction away from the clutch center 12, the control pin 31 is moved away from the reed valve 25, and the pressure plate 13
Since the through hole 13c is closed, the hydraulic chamber 22
The pressure plate 13 is pressed toward the clutch center 12 by the pressure of the hydraulic oil supplied inside the clutch outer 11 , which increases the pressure of the friction plates 19 and 20 described above to generate a sufficient pressure. Power is reliably transmitted from the clutch center 12 to the clutch center 12.

The hydraulic fluid supplied to the hydraulic chamber 22 is kept at an appropriate pressure P by the pressure regulating valve 40. Moreover, since the above-mentioned adjustment is performed in the rotation range of the prime mover after the connection point of the clutch mechanism 9, the pressure of the lubricating oil discharged from the relief valve 39 increases as the rotation of the prime mover increases. Furthermore, even if the pressure of the i2 lubricating oil fluctuates due to fluctuations in rotation of the prime mover, the pressure of the hydraulic oil in the clutch mechanism 9 is maintained constant, and the connection state between the clutch outer 11 and the clutch center 12 is maintained. is held constant.

Further, when the camshaft 35 is operated to disengage the clutch, the clutch outer 11 and the clutch center 12 go through a half-clutch state in accordance with the amount of operation of the camshaft 35.
The rotation of the camshaft 35 causes the suppression member 33 to move toward the clutch center 12, but the stopper 28 and the pressure plate 13 are moved toward the control spring 30. Since it is elastically supported by the clutch spring 29 which is stronger than the clutch spring 29, only the suppressing member 33 is moved toward the clutch center 12 and the plane plate I3 while elastically deforming the control spring 30. year plate 13
The control pin 31 is brought into contact with the reed valve 25 by the relative movement between the reed valve 25 and the reed valve 25, and the reed valve 25 is pressed open by the control pin 31, and the hydraulic fluid in the hydraulic chamber 22 is discharged. As a result, the pressure within the hydraulic chamber 22 is reduced, and the pressing force of each friction plate 19, 20 is reduced. And the reed valve 2
The opening area of 5 gradually increases in accordance with the amount of movement of the lifter plate 26, and reaches its maximum when the lifter plate 26 comes into contact with the pressure plate 13, but at this point it is limited by the fixed orifice 44. Due to the balance between the amount of hydraulic oil flowing into the hydraulic chamber 22 and the amount discharged from the through hole L3c, the pressing force applied to the pressure plate 13 by the hydraulic oil is minimized, and the half-clutch state as described above is achieved. will be moved to.

Even in the process of transitioning to such a half-clutch state,
Since pressure fluctuations in the hydraulic oil sent to the clutch mechanism 9 are suppressed by the pressure regulating valve 40, the connection state between the clutch outer 11 and the clutch center 12 can be accurately controlled.

Furthermore, when the amount of operation of the camshaft 35 is increased, the lifter plate 26 is brought into contact with the pressure plate 13, and then, against the elastic force of the clutch spring 299, the pressing member 33, the lifter plate 26, Then, the pressure plate 13 is moved integrally, and each friction plate 19 is moved by the pressure plate 13.
By reducing the pressing force applied to clutch 20, clutch outer 11 and clutch center I2 are completely separated, resulting in a clutch disengaged state. In this state as well, the pressure of the hydraulic oil is maintained constant as in the case of the half-engaged clutch, and the clutch disengaged state is stably maintained.

Note that the shapes, dimensions, etc. of each component shown in the above embodiments are merely examples, and can be variously changed based on design requirements and the like.

For example, an example is shown in which a reduction valve is used as the pressure regulating valve 40, but instead of this, a sub-relief valve 49 may be used as shown in FIG.

However, in this case, in order to keep the pressure of the hydraulic oil constant, excess oil must be discharged due to the structure of the relief valve, and the load on the oil pump 37 tends to increase accordingly. Therefore, in order to eliminate this problem as much as possible, it is necessary to provide a fixed orifice 50 between the relief valve 39 and the sub-relief valve 49 to limit the amount of oil sent to the sub-relief valve 49. It goes without saying that the amount of oil limited by the fixed orifice 50 exceeds the amount necessary for the operation of the clutch mechanism 9.

"Effects of the Invention" As explained above, the hydraulic clutch according to the present invention has
a clutch center; a clutch outer rotatable relative to the clutch center; a friction plate that engages only the clutch center; a friction plate that engages only the club chia outer; the clutch center and the clutch outer; is moved hydraulically in the direction of the rotational axis of the
A pressure plate that engages and disengages the clutch center and the club tire outer through the friction plates by bringing the friction plates into pressure contact with each other, and a hydraulic oil control device for controlling the hydraulic pressure applied to the pressure plate. The hydraulic oil control device includes: iif an oil pump that pressurizes the hydraulic pump; a hydraulic oil supply path that communicates between the oil pump and the pressure plate; and a relief provided in the middle of the hydraulic oil supply path. It is characterized by comprising a valve and a pressure regulating valve provided between the relief valve and the pressure plate, and prevents the pressure of hydraulic oil applied to the pressure plate from being generated by an oil pump. As below the maximum pressure that can be
The pressure of the hydraulic oil is brought closer to the optimum pressure for performing the clutch engagement operation, and the pressure fluctuation of the hydraulic oil in the area where the clutch engagement operation is performed is suppressed to ensure the clutch engagement operation. It has excellent effects such as:

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing an example of the structure of a conventional hydraulic clutch, Fig. 2 is a diagram for explaining pressure changes in hydraulic oil, and Fig. 3 is a schematic diagram showing an example of the structure of a conventional hydraulic clutch.
The figure is a diagram for explaining pressure adjustment of hydraulic oil, Figure 4 is a sectional view showing one embodiment of the present invention, and Figure 5 is a diagram similar to Figure 1 showing another embodiment of the present invention. be. 8... Hydraulic clutch, 9... Clutch mechanism, 10...
・・Hydraulic oil control device, 11・・Clutch outer, 12・
...Clutch center, 13...Pressure plate, 14...Main shaft, 19, 20...Friction plate, 21a...Backup plate, 22...Hydraulic chamber, 22, 23...Protrusion, 2
5... Reed valve, 26... Lifter plate, 28... Stopper, 29... Clutch spring, 30... Control spring, 31... Control pin, 33... Suppressing member, 35...・Camshaft, 36・
...Operation lever, 37...Oil pump, 38...
Hydraulic oil supply path, 39...Relief valve, 40...
Pressure regulating valve, 41...feed pipe, 41a
・41b...Communication path, 42...Through hole, 43...
Communication path, 44... fixed orifice, 45...
・Body, 46...Pressure regulating piston, 46a
...Communication hole, 47...Pressure adjustment spring, 48
...Secondary chamber, 49...Sub-relief valve, 50...Fixed orifice.

Claims (1)

[Claims] a clutch center, a clutch outer rotatably provided relative to the clutch center, a friction plate that engages only the clutch center, a friction plate that engages only the clutch outer, and the clutch center and the clutch outer. A pressure plate that is moved by hydraulic pressure in the direction of the rotational axis of the clutch and presses each of the friction plates to engage and disengage the clutch center and the clutch outer through the friction plates, and a pressure plate that acts on the pressure plate. a hydraulic oil control device for controlling the hydraulic pressure applied to the hydraulic oil; the hydraulic oil control device includes an oil pump that pressurizes the hydraulic oil; a hydraulic oil supply path that communicates between the oil pump and the pressure plate; A hydraulic clutch comprising: a relief valve provided in the middle of the hydraulic oil supply path; and a pressure regulating valve provided between the relief valve and the pressure plate.