JP2001050301A - Clutch device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent decrease in transmission efficiency of a transmission gear caused by stirring of oil and dragging of a frictional engaging element by removing oversupply of cancel oil from a canceller improving controllability of a clutch to a lubricating part. SOLUTION: This clutch device is provided with a piston cylinder mechanism rotated together with a clutch drum 31, a cancel plate 33 behind a piston 32, and a cancel chamber B partitioned by the piston 32, an inner peripheral part 31a of the clutch drum 31 and the cancel plate 38. The clutch drum 31 is formed with a cancel oil passage C opening in the cancel chamber B and a back face of the clutch drum 31 to drain the cancel oil to the back of the clutch drum 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clutch device, and more particularly to a technology for canceling centrifugal hydraulic pressure in a clutch device suitable for use in an automatic transmission.

[0002]

2. Description of the Related Art In a wet-type multi-plate clutch device,
Unlike the hydraulic servo of the brake, the hydraulic servo that engages and disengages the friction engagement element that performs power transmission rotates together with its own clutch drum that constitutes the power transmission path. Centrifugal force acts on the hydraulic oil supplied into the room. As described above, the centrifugal force applied to the hydraulic oil generates a centrifugal oil pressure that increases the oil pressure in the cylinder chamber toward the outer diameter side, which not only makes it difficult to control the supply oil pressure when the clutch is engaged, but also causes the oil pressure when the clutch is released. Emission of water.

As one countermeasure against such generation of centrifugal hydraulic pressure, a cancel plate is provided behind the clutch piston, and a cancel chamber defined by the piston, the inner peripheral portion of the clutch drum and the cancel plate is provided, and the cancel chamber is provided in the cancel chamber. There is a technique for canceling the centrifugal oil pressure in the cylinder chamber by the generated centrifugal oil pressure. JP-A-2-296
The technology disclosed in Japanese Patent Application Laid-Open No. 072 is related to the discharge of hydraulic pressure from the canceller mechanism. In this technology, a groove is provided on the inner peripheral side of the cancel plate, and the notch is provided on the back surface of the cancel plate. By communicating with
In order to restrict the axial movement of the cancel plate, a discharge path is provided which bypasses the snap ring which is in contact with the back surface of the cancel plate.

[0004]

Generally, in a canceller mechanism having such a cancel chamber, when the operation is stopped, the supply of oil is stopped, and when the rotation of the clutch drum is stopped, most of the oil in the cancel chamber is discharged. Therefore, in order to quickly fill the room with oil in preparation for clutch engagement at the time of restart of operation, the cancel room is communicated with a supply oil passage that supplies a large amount of oil. In addition, the volume of the cancel chamber must be reduced quickly so that the piston does not become resistant to the stroke of the piston when the clutch is engaged. Size.

Under these circumstances, a large amount of oil is continuously supplied to the cancel room during operation, and a large amount of oil overflows therefrom. When such a large amount of discharged oil is supplied to the friction engagement elements located on the outer peripheral side of the discharge portion, the oil enters the gaps between the friction engagement elements when the clutch is released, causing dragging resistance in the clutch, thereby increasing the transmission efficiency. Is a factor in the decline.

[0006] On the other hand, a configuration is adopted in which the oil in the overflow from the cancel chamber is drained upward from the cancel chamber in order to avoid the oil from flowing out of the cancel chamber due to the stop of the oil supply as described above. (See Japanese Utility Model Laid-Open No. 6-12868). However, if such a configuration is adopted, it is necessary to seal the drain oil passage, and in particular, it is necessary to dispose a seal member which causes an increase in sliding resistance in a relative rotation part between the oil passages. The drain oil passage extends from the inner periphery of the cancellation chamber to the vicinity of the outer peripheral wall of the case through the shaft oil passage and the case wall oil passage, and the degree of freedom in the arrangement of other elements and oil passages that constitute the transmission device Such a technique is not always practically effective because it significantly limits

The present invention has been made in view of such circumstances, and by changing the direction in which oil is discharged from the cancel chamber by a simple mechanism, it is possible to prevent oil agitation due to excessive lubrication of the friction engagement element. An object of the present invention is to provide a clutch device that eliminates drag when the clutch is released and prevents a reduction in transmission efficiency.

[0008]

In order to achieve the above object, the present invention comprises a piston cylinder mechanism which rotates together with a clutch drum, a cancel plate is provided behind the piston, and the inner circumference of the piston and the clutch drum. In a clutch device provided with a cancel chamber defined by a portion and a cancel plate, a cancel oil passage communicating with the cancel chamber and a back surface of the clutch drum is formed in the clutch drum.

In the above configuration, the cancellation oil passage is
It is effective to adopt a configuration formed on the inner peripheral portion of the clutch drum.

Further, the cancel oil passage is fitted into the cancel oil groove formed of at least one groove formed on the inner peripheral surface of the inner peripheral portion of the clutch drum and the inner peripheral portion of the clutch drum. The cancel oil passage is defined by a sleeve that covers an open surface side of the cancel oil groove, and the cancel oil passage includes a supply hole that communicates the cancel oil groove with a supply oil passage of the cancel oil, and a supply / discharge hole that communicates the cancel oil groove with the cancel chamber. It is effective to adopt a configuration having a discharge hole for opening the cancel oil groove to the back surface of the clutch drum.

Further, at least one clutch oil groove is formed on the inner peripheral surface of the inner peripheral portion of the clutch drum in parallel with the cancel oil groove, and the clutch oil groove is fitted into the inner peripheral portion of the clutch drum. The open sleeve is covered by the sleeve to define a clutch pressure oil passage, and the clutch pressure oil passage is connected to a clutch oil supply passage and a clutch oil chamber defined by the clutch drum and the piston. Is effective.

Further, it is effective that the supply hole and the discharge hole of the cancel oil passage are provided so as to be offset from each other in the axial direction with respect to the cancel oil groove.

In each of the above configurations, the cancel oil passage is constituted by a first cancel oil groove having a supply hole and a supply / discharge hole, and a second cancel oil groove having a supply / discharge hole and a discharge hole. You can also.

Further, the cancel plate abuts on a snap ring fitted on the outer peripheral surface of the inner peripheral portion of the clutch drum to restrict its movement in the axial direction, and the inner peripheral surface of the cancel plate and the inner peripheral portion of the clutch drum are restricted. It is effective to adopt a configuration in which a minute gap is held between the outer peripheral surface and the outer peripheral surface.

[0015]

According to the structure of the first aspect,
Since the canceling oil is drained to the back of the clutch drum, the drag of the clutch caused by the large amount of oil drained by the high-speed rotating clutch drum, hub, or friction engagement element is reduced, and the rotational resistance is reduced. Can improve the efficiency of a transmission device incorporating the same. In addition, since the drain oil passage is provided in the clutch drum, the drain can be drained without passing through other members, particularly the stationary member, and thereby the centrifugal force is used from the clutch drum that rotates the cancel oil at the same speed as the cancel chamber. The discharge resistance can be reduced. Furthermore, since the drainage without draining through the relative rotating portion does not require the use of a special seal ring or the like that generates sliding resistance, the efficiency of the transmission can be improved.

According to the second aspect of the present invention, by supplying and draining the cancel oil in the inner peripheral portion of the clutch drum, the cancel oil passage can be formed without affecting the structure of the piston and the clutch oil chamber. Can be configured.

Furthermore, in the configuration according to the third aspect, the cancel oil passage is defined by the groove provided on the inner peripheral portion of the clutch drum and the sleeve fitted into the inner peripheral portion of the drum.
By providing a cancel oil passage in the inner peripheral portion of the drum, the increase in the diameter of the inner peripheral portion of the drum can be minimized.

According to the fourth aspect of the present invention, the clutch pressure oil passage is formed by a groove so that the communication position between the clutch oil chamber and the clutch pressure supply oil passage in the clutch pressure oil passage is offset in the axial direction. Is possible, thereby increasing the degree of freedom in designing the clutch. Further, with this configuration, the clutch pressure oil passage and the cancel oil passage can be arranged on the same circumference, so that it is necessary to increase the diameter of the inner circumference of the clutch drum by providing the cancel oil passage on the inner periphery of the clutch drum. Absent.

According to the fifth aspect of the present invention, the oil pressure path for supplying the cancel oil and the oil path for draining are shared, so that the clutch pressure oil path is provided in parallel in the circumferential direction. Since the total number of oil passages of the oil passage and the cancellation oil passage can be reduced and the area of each cross section can be made relatively large, the controllability of the clutch can be improved. In addition, in the case of this configuration, since the supply hole and the discharge hole of the cancel oil with respect to the cancel groove are offset in the axial direction, the drain amount due to the shortcut between the two holes can be reduced, and the common oil passage is used. Also, the amount of oil supplied to the cancel chamber can be secured.

Further, in the configuration according to the sixth aspect, the supply of the cancel oil through the cancel oil passage and the drain can be separated, so that the oil on the supply side to the cancel oil chamber is drained on the way. In other words, the entire amount is always supplied to the cancel chamber, so that it is not necessary to supply more cancel oil than necessary in consideration of the drainage from the middle.

Further, according to the configuration of the seventh aspect, the friction engagement element can be lubricated with an appropriate amount of oil by the cancel oil leaked from the minute gap between the cancel plate and the inner peripheral side cylinder.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an axial section of a first embodiment in which the clutch device of the present invention is applied to an automatic transmission. As shown in the figure, the clutch device includes a piston cylinder mechanism that rotates together with the clutch drum 31.
A cancel plate 33 is provided on the side opposite to 1, and a cancel chamber B defined by the piston 32, the inner peripheral portion 31a of the clutch drum, and the cancel plate 33 is provided.

According to a feature of the present invention, the clutch drum 31
In addition, a cancel oil passage C is formed which is open and communicates with the cancel chamber B and the back surface of the clutch drum 31, that is, the surface of the clutch drum 31 opposite to the cancel chamber B side. The cancel oil passage C is formed in the inner peripheral portion 31a of the clutch drum, and as shown in FIG.
a, which is formed in the axial direction on the inner peripheral surface of the clutch oil groove and is composed of two grooves, and a sleeve which is inserted into the inner peripheral portion 31a of the clutch drum and covers the open surface side of the cancel oil groove Ca. 34.

The cancel oil passage C has a supply hole Cb provided in the sleeve 34 for communicating the cancel oil groove Ca with a cancel oil supply oil passage R provided in the input shaft.
A supply / discharge hole Cc provided in the inner peripheral portion 31a of the clutch drum and communicating the cancel oil groove Ca with the cancel chamber B;
And a discharge hole Cd for opening the cancel oil groove Ca on the back surface of the clutch drum 31.

As shown in FIG. 2, two clutch oil grooves Da are formed on the inner peripheral surface of the inner peripheral portion 31a of the clutch drum in this embodiment in parallel with the cancel oil groove Ca. An open surface side is covered by a sleeve 34 inserted into the inner peripheral portion 31a of the clutch drum to define a clutch pressure oil passage D. The clutch pressure oil passage D communicates with a clutch oil chamber A defined by the clutch drum 31 and the piston 32 and a clutch pressure supply oil passage S.

In this embodiment, the supply passage Cb and the discharge hole C of the cancel oil passage C are arranged as shown in FIG.
“d” is provided so as to be shifted from each other in the axial direction with respect to the cancel oil groove C.

The cancel plate 33 has a snap ring 3 fitted on the outer peripheral surface of the inner peripheral portion 31a of the clutch drum.
5, the movement in the axial direction is restricted, and a minute gap is held between the inner peripheral surface of the cancel plate 33 and the outer peripheral surface of the inner peripheral portion 31a of the clutch drum.

Hereinafter, the configuration of each section will be described in more detail. FIG. 4 is a skeleton diagram showing a schematic configuration of an example of an automatic transmission to which the clutch device of the present invention is applied. This transmission is configured as a transaxle having a three-axis configuration, and includes a torque converter T as a starting device, a forward six-speed and reverse first-speed transmission mechanism mainly including a Ravigneaux-type planetary gear set G, and a counter gear. It comprises a mechanism and a differential device. The transmission mechanism includes an input shaft 11 connected to a turbine runner of the torque converter T.
Planetary gear set G1 for reducing the rotation of the planetary gear set G and inputting it to the planetary gear set G; -3), a clutch (C-2) for directly inputting the rotation of the input shaft 11 to the carriers C2 and C3 of the planetary gear set G, and a brake for locking one sun gear S2 of the planetary gear set G to the transmission case 10 ( B
-1) and a brake (B-2) for locking the carrier C2 of the planetary gear set G to the transmission case 10 in parallel.
And a one-way clutch (F-1), and the ring gear R3 of the planetary gear set G is an output element connected to the output shaft 19.

The automatic transmission having such a configuration is shown in FIG.
As shown in FIG. 5, the operation can be achieved in six stages of forward speed and first reverse speed with good gear ratio steps. And, in order to make use of this multi-stage characteristic effectively,
This transmission employs a control mode in which the gears can be freely jumped between the gears, and the clutch ( Regarding C-1), a clutch incorporating a centrifugal oil pressure canceling mechanism is used.

The clutch (C-1) to which the present invention is applied
As shown in FIG. 1, a hub 37 integrally formed with a hub of a clutch (C-3) is used as an input member for connecting to a carrier C1 of a reduction planetary gear G1, and the hub 37 has a separator plate 38A and a friction material disk 38B. Clutch drum 31 connected via a friction engagement element 38 comprising
Are connected to the sun gear S3 of the planetary gear set G by spline engagement.

In this embodiment, the drum 31 of the clutch (C-1) has a cylinder portion 31A constituting a hydraulic servo cylinder on the inner peripheral side thereof, and a drum portion 31B fixedly integrated on the outer periphery thereof by welding or the like. The inner cylinder portion 31A has a cylindrical inner peripheral portion 31a supported via a bush on the outer periphery of the front input shaft 11A which is divided into front and rear parts and spline-connected to each other, and a coaxial portion thereof. An outer peripheral portion 31b is formed by a short cylindrical outer peripheral portion 31b, and a radial wall 31c connecting the outer peripheral portion 31b at the axial center portion and the axial rear end side.
The rear end of a is connected to the shaft portion of the sun gear S3 by sprunk fitting. O-rings are inserted into the outer periphery of the outer peripheral portion 31b and the outer periphery of the inner peripheral portion 31a, respectively. Unit. The cylindrical portion on the outer peripheral side of the drum portion 31B is formed with a splint by press working, and constitutes a detent support portion of the separator plate 38A of the frictional engagement element that is spline-engaged therewith.

The piston 32, which is slidably fitted to the cylinder portion 31A, is formed in a disk shape having a cylindrical portion on its inner and outer circumferences. The rear extension of the cylindrical portion fitted to the outer periphery of the peripheral portion 31a and extending in the front-rear direction in the axial direction on the outer peripheral side is connected to the drum outer peripheral portion 31b.
The flange-like portion fitted to the outer periphery of the first member and projecting in the outer diameter direction from the rear extension portion serves as a pressing portion of the friction engagement element.

The cancel plate 33 disposed on the front side of the drum inner peripheral portion 31a has its outer peripheral side connected to the inner peripheral portion of the front extension of the drum outer peripheral portion 31b via a seal ring disposed on the outer periphery by baking or the like. It is supported, and the outer periphery thereof is disposed in contact with the snap ring 35 fitted to the outer periphery of the front end of the drum inner peripheral portion 31a as described above. In the cancel chamber B, one end is brought into contact with the radial wall 31c of the piston 32 via a spring seat, and the other end is
A return spring 36 composed of a large number of coil springs arranged at equal intervals in the circumferential direction in contact with the plate surface of No. 3
Are arranged.

On the input shaft 11A on which the clutch drum 31 is rotatably supported, two parallel in-shaft oil passages R and S are formed. Among these oil paths, one oil path S is
A front part (not shown) is connected to a servo pressure supply oil passage of the transmission case via a rotary seal portion, and the rear end is closed by a ball 11a, and is opened in a circumferential groove 11c on the outer periphery of the shaft by a radial hole 11b. I have. A pair of seal rings 11e is disposed in front and rear of the circumferential groove 11c in the axial direction, and seals a relative rotating portion between the sleeve 34 fitted to the inner circumferential portion 31a of the drum and the input shaft 11A. At the axial position corresponding to the circumferential groove 11c and at the position corresponding to the circumferential position of the clutch oil groove Da, a radial hole Db penetrating the sleeve 34 is formed as a supply / discharge hole. It is open at the front end of the oil groove Da. The rear end of the clutch oil groove Da communicates with the clutch oil chamber A through a supply / discharge hole formed by a radial hole Dc in the drum inner peripheral portion 31a.

The other oil passage R formed on the input shaft 11A is:
It is open at the connection between the input shaft 11A and the input shaft 11B,
This space is narrowed by an opening of a bowl-shaped orifice plate fitted in the oil passage in the shaft of the input shaft 11B, communicates with the rear of the input shaft 11B, and has a radial hole 1 formed in the input shaft 11A.
1d constitutes a lubricating oil passage opened behind the seal ring and in front of the bush. The sleeve 34 fitted to the inner peripheral portion 31a of the clutch drum has an axial hole Cb passing through the sleeve 34 at a position corresponding to the release portion at a position corresponding to the circumferential position of the cancel oil groove Ca.
Is formed, and this hole constitutes a cancel oil supply hole.

In the automatic transmission having such a configuration, the supply of the hydraulic pressure to the clutch (C-1) is performed by the in-shaft oil passage S of the input shaft 11A which communicates on the front side with the in-case oil passage of the transmission.
Radial oil passage 11b, circumferential groove 11c, radial hole Db, clutch oil groove Da and radial hole D extending axially therefrom.
c.

On the other hand, the other input shaft 11A of the input shaft 11A which communicates on the front side with the supply oil passage (not shown) of the lubricating pressure in the case of the transmission to the cancel chamber B of the clutch (C-1). An oil passage R, a gap between connecting portions of the input shafts 11A and 11B,
This is performed through the radial oil hole 11d of the input shaft 11A, the circumferential gap at the step on the outer periphery of the input shaft 11A, the supply hole Cb of the sleeve 34, the cancel oil groove Ca and the supply / discharge hole Cc of the drum inner peripheral portion 31a.

The oil thus supplied to the cancel chamber Rc is always in a state of filling the cancel chamber B by its continuous supply, and is connected to the input shaft 11A via the reduction planetary gear G1 (see FIG. 4). The piston 32 receives centrifugal force in the clutch drum 31 that is constantly decelerating and rotating, regardless of whether hydraulic pressure is supplied to the clutch oil chamber A or not.
Load centrifugal hydraulic pressure behind. The surplus oil flows from the cancel oil passage C, which mainly includes the supply / discharge holes Cc, the cancel oil grooves Ca, and the discharge holes Cd, to the rear of the clutch drum 31 and a small amount thereof from the outer periphery of the drum inner peripheral portion 31a to the cancel plate 33. The gap between the inner circumference and the snap ring 35
Is discharged to the outside through the cut, and is sprayed on the clutch hub 37 on the outer peripheral side.

When hydraulic pressure is supplied to the clutch oil chamber A, the cancel chamber B is moved with the piston stroke.
Therefore, the oil filling the cancel chamber C is forcibly discharged to the outside through the same route.

As described above, according to the present embodiment, since the cancel oil is drained to the back of the clutch drum 31, a large amount of oil is drained by the clutch drum 31, the hub 37, or the friction engagement element 38 which rotates at high speed. Thus, the drag of the clutch caused by the oil is reduced, and the rotational resistance is reduced, so that the efficiency of the automatic transmission incorporating the clutch can be improved. Further, since the drain oil passage is provided in the clutch drum 31, the drain can be drained without passing through other members, especially the stationary member, whereby the cancel oil is centrifuged from the clutch drum 31 rotating at the same speed as the cancel chamber B. Since the discharge can be performed using the force, the discharge resistance can be reduced. Furthermore, since the drainage without draining through the relative rotating portion does not require the use of a special seal ring or the like that generates sliding resistance, the efficiency of the transmission can be improved.

Further, with respect to the clutch pressure oil passage D, a supply / discharge hole Dc communicating the clutch oil groove Da with the clutch oil chamber A is provided.
And a supply / drainage hole D communicating the clutch oil groove Da with the circumferential groove 11c.
b is arranged offset in the axial direction, so that the circumferential groove 1
Since the arrangement position of the clutch oil chamber A with respect to the axial position 1c can be set relatively freely, the degree of freedom in designing the clutch is increased. Further, the clutch oil groove Da and the cancel groove Ca are arranged in parallel to the same radial position by making the circumferential positions different from each other,
The necessity of increasing the diameter of the inner peripheral portion 31a of the clutch drum due to the provision of the cancel oil passage C in the inner peripheral portion 31a of the clutch drum is eliminated.

Since the oil supply passage and the drain oil passage for the cancel oil for the cancel chamber B are shared, the number of the clutch oil passages D and the number of the cancel oil passages provided in parallel in the circumferential direction can be reduced. The controllability of the clutch is improved by making it possible to increase the area of each cross section relatively. Further, regarding the cancel oil passage C, the supply hole Cb and the discharge hole Cd, both of which communicate with the cancel oil supply oil passage R via the cancel oil passage Ca, are offset in the axial direction. The amount can be reduced, and the amount of oil supplied to the cancel oil chamber B can be ensured while using a common oil passage.

Next, FIG. 6 shows a second embodiment of the present invention. In this embodiment, the cancel oil passage C has a clutch pressure oil passage (the figure shows a cross section which does not pass through the position of the clutch oil groove). ), A first cancel oil groove comprising two types of different oil passages provided at mutually different circumferential positions avoiding the circumferential position, and having a supply hole Cb and a supply / discharge hole Cc shown below in the figure. Ca1 and a second cancel oil groove Ca2 having a supply / discharge hole Cb and a discharge hole Cd shown at the top in the figure. Other configurations are the same as those of the first embodiment, and the corresponding members are denoted by the same reference numerals and description thereof will not be repeated.

With such a configuration, the oil on the supply side to the cancel chamber B is exclusively used for the supply hole Cb, the first cancel oil groove Ca1, and the supply / discharge hole C1, which constitute one of the cancel oil passages.
c, and the overflow is supplied to the cancel chamber B via the supply / discharge hole Cc, the second cancel oil groove Ca2, and the discharge hole Cd constituting the other cancel oil passage. Will be released. Thus, the second
According to the configuration of the embodiment, there is no possibility that the cancel oil is drained in the middle of the cancel oil path, and the entire amount is always supplied to the cancel chamber B from one cancel oil path. It is possible to eliminate the waste of supplying unnecessary cancel oil in consideration of the amount.

As described above, the present invention has been described in detail based on the embodiments. However, the present invention is not limited to the illustrated embodiments, and various concrete configurations may be changed within the scope of the claims. It can be implemented. For example, the number of the clutch oil grooves Da and the number of the cancel grooves Ca can be set arbitrarily, and the supply holes Cb and the supply / discharge holes D communicating with them are provided.
b, Dc, Cc and the number of discharge holes Cd can also be set arbitrarily.

[Brief description of the drawings]

FIG. 1 is an axial partial cross-sectional view of a first embodiment of a clutch device according to the present invention incorporated in an automatic transmission.

FIG. 2 is a rear view of a cylinder portion of a clutch drum of the clutch device as viewed in an axial direction.

FIG. 3 is a development view showing a configuration of a cancel oil passage and a clutch pressure oil passage when the clutch drum is viewed from an inner peripheral surface side.

FIG. 4 is a skeleton diagram showing an overall configuration of the automatic transmission.

FIG. 5 is an operation chart of the automatic transmission.

FIG. 6 is an axial partial cross-sectional view illustrating a cancel oil passage structure of a clutch device according to a second embodiment.

[Explanation of symbols]

 31 clutch drum 31a drum inner circumference 32 piston 33 cancel plate 34 sleeve 35 snap ring A clutch oil chamber B cancel chamber C cancel oil path Ca cancel oil groove Ca1 first cancel oil groove Ca2 second cancel oil groove Cb supply hole Cc supply / discharge hole Cd discharge hole D clutch pressure oil passage Da clutch oil groove S clutch pressure supply oil passage

Continued on the front page (72) Inventor Akitoshi Kato 10 Takane, Fujii-machi, Anjo-shi, Aichi F-term in Aisin AW Co., Ltd. 3J057 AA04 BB04 CA01 CA03 DA01 GA17 HH01 JJ04 3J067 AC01 EA03 GA01

Claims (7)

[Claims] 1. A clutch comprising: a piston cylinder mechanism that rotates together with a clutch drum; a cancel plate provided behind the piston; and a cancel chamber defined by the piston, an inner peripheral portion of the clutch drum, and the cancel plate. A clutch device, wherein a cancel oil passage communicating with a cancel chamber and a back surface of the clutch drum is formed in the clutch drum. 2. The clutch device according to claim 1, wherein the cancel oil passage is formed in an inner peripheral portion of a clutch drum. 3. The cancel oil passage is formed by inserting at least one groove formed on an inner peripheral surface of an inner peripheral portion of the clutch drum into a cancel oil groove and an inner peripheral portion of the clutch drum. The cancel oil passage is defined by a sleeve that covers the open surface side of the cancel oil groove, and the cancel oil passage is a supply hole that communicates the cancel oil groove with a supply oil passage of cancel oil, and a supply / discharge hole that communicates the cancel oil groove with the cancel chamber. 3. The clutch device according to claim 1, further comprising a discharge hole that opens the cancel oil groove to a back surface of the clutch drum. 4. 4. At least one clutch oil groove is formed on an inner peripheral surface of an inner peripheral portion of the clutch drum in parallel with the cancel oil groove, and the clutch oil groove is fitted into the inner peripheral portion of the clutch drum. The clutch pressure oil passage is defined by covering an open surface side with the sleeve, and the clutch pressure oil passage is communicated with a clutch oil supply passage and a clutch oil chamber defined by a clutch drum and a piston. 4. The clutch device according to 1, 2, or 3. 5. The clutch device according to claim 4, wherein the supply hole and the discharge hole of the cancel oil passage are provided so as to be offset from each other in the axial direction with respect to the cancel oil groove. 6. The cancel oil passage, comprising: a first cancel oil groove having a supply hole and a supply / discharge hole; and a second cancel oil groove having a supply / discharge hole and a discharge hole. Item 5. The clutch device according to any one of Items 1 to 4. 7. An axial movement of the cancel plate is restricted by contacting a snap ring fitted on an outer peripheral surface of an inner peripheral portion of the clutch drum, and an inner peripheral surface of the cancel plate and an inner peripheral portion of the clutch drum. A minute gap is held between the outer peripheral surface and the outer peripheral surface.
7. The clutch device according to claim 6, wherein: