JPH04157212A - Wet type multiple-disc clutch - Google Patents

Abstract

PURPOSE:To reduce drag torque by installing an elastic member whose dimension is bigger than that in the rotational direction of the first plate, and coefficient of friction of a surface coming into contact with the second plate is smaller than that of the first plate surface, between the first and second plates. CONSTITUTION:The first plate (drive plate) 1 includes a core plate 2, a facing 3 of friction member, and an elastic member 4. The elastic member 4 consists of a basic part 4a and a truncated cone type projection 4b, and projects from the facing 3. The projecting amount D is a value which can ensure clearance between plates necessary to reduce drag torque. The coefficient of friction of the elastic member 4 is smaller than that of the facing 3, and the contacting area with the driven plate is very small. It is thus possible to reduce drag torque and power loss.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a wet multi-plate clutch used in a power transmission member such as an automatic transmission.

(Prior Art) As a conventional wet type multi-disc clutch, there is one shown in FIG. 3, for example. FIG. 3 is a sectional view showing such a wet type multi-disc clutch.

Reference numeral 101 denotes a drive plate as a first plate, which is composed of a metal disc-shaped core plate 102 and a disc-shaped facing 103 as a friction member bonded to the core plate 102.

A clutch hub 104 is a substantially cylindrical rotating member, and a groove 104a is provided on the outer periphery of the clutch hub.

The drive plate 101 is engaged with the groove 104a, and the drive plate 101 and clutch hub 104 rotate integrally.

Reference numeral 105 denotes a driven plate as a second plate, which is a metal disc-shaped plate. Of the driven plates 105, the one on the left end in the figure is the snap ring 1.
06 restricts movement to the left in the figure.

A clutch drum 107 is a substantially cylindrical rotating member, has a larger diameter than the clutch hub 104, and is provided with a groove 107a on its inner periphery. A driven plate 105 is engaged with the groove 107a, and the driven plate 105 and clutch drum 107 rotate integrally.

Then, the drive plate 101 and the driven plate 1
05 are arranged alternately.

108 is a piston, which is biased to the right in the figure by a return spring 109. The piston 108 is provided with seal members 110 and 111, and a pressure chamber 112 is provided at the gate between the piston 108 and the clutch drum 107.
are defined in a liquid-tight manner.

When hydraulic fluid is supplied to the pressure chamber 112 through the passage 113, the piston 108 moves to the left in the figure, causing the drive plate 101 and the driven plate 105 to come into pressure contact, and the clutch hub 104 and the clutch drum 10
Rotational force is transmitted between the two. In other words, the wet multi-disc clutch is in the engaged state. In addition, the pressure chamber 11
When the hydraulic fluid No. 2 is discharged, the piston 108 moves to the right in the figure, thereby separating the drive plate 101 and the driven plate 105, and the wet multi-disc clutch becomes in a non-engaged state.

In addition, lubricating oil is supplied to the center of the rotating shaft (not shown), and the lubricating oil is applied to the drive plate 101 by centrifugal force.
and the driven plate 105.

(Problem to be solved by the invention) In such a wet multi-plate fastening device, drag torque (dragging) occurs between the plates due to the viscosity of the rA lubricating oil that exists between the plates when they are not fastened, resulting in power loss. It was structured so that you could get it. As shown in FIG. 4, the drag torque increases as the clearance C between the plates decreases, but if the clearance C falls below CoJX due to the drive plate 101 falling down, the drag torque becomes significantly large. There is a problem in that the power loss of the plate clutch increases, and in vehicles equipped with a power transmission member such as an automatic transmission to which such a wet multi-plate clutch is applied, deterioration in fuel efficiency is unavoidable.

In the present invention, it is an object of the present invention to obtain a wet multi-disc clutch that reduces power loss by reducing drag torque.
Let it be l.

(Means for Solving 11m) In order to solve the above problem, in the present invention, by bringing a disc-shaped first plate and a disc-shaped second plate into pressure contact, a rotational force is generated between the two plates. In a wet type multi-disc clutch for transmitting a transmission, the first plate is provided with an elastic member that contacts the second plate, and the dimension of the elastic member in the direction of the rotation axis is larger than the dimension of the first plate in the direction of the rotation axis, and The elastic member is characterized in that the friction coefficient of the surface that contacts the second plate is smaller than the *m coefficient of the surface of the first plate.

(Function) Since the dimension of the elastic member provided on the first plate in the direction of the rotation axis is larger than the dimension of the first plate in the direction of the rotation axis, when the wet multi-disc clutch is not engaged, the first plate and the second
Clearance with the plate is maintained. At this time,
Since the friction coefficient of the elastic member is smaller than the am coefficient of the surface of the first plate, power loss due to the elastic member contacting the second plate is small. - On the other hand, when the wet multi-disc clutch is engaged, the elastic member is compressed in the direction of the rotational axis and does not prevent the transmission of rotational force between the first plate and the second plate.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. Here, the same reference numerals are attached to the same members as in the prior art to simplify the explanation.

FIG. 2 is an exploded perspective view showing the structure of the first plate used in the wet type multi-disc clutch according to the present invention, and FIG. 1 is a 1-1 sectional view of the first plate in FIG. 2.

As shown in FIG. 1, a drive plate 1 as a first plate is composed of a metal disc-shaped core plate 2, a disc-shaped facing 3 as a friction member, and an elastic member 4.

The elastic member 4 consists of a disc-shaped base 4a and a truncated conical protrusion 4b coaxial with the rotation axis of the base 4a, which is formed on both sides of the base 4a. It is configured to protrude from the surface. Here, the protrusion amount of the protrusion 4b is set to a value that can ensure the clearance Go between the plates, which is necessary to reduce drag torque when the wet multi-disc clutch is not engaged. Moreover, the elastic member 4 is II! Materials with a coefficient of friction smaller than facing 3, such as fluorine resin, fluorine rubber,
Alternatively, it is made of acrylic rubber or the like.

As shown in FIG. 2, the core plate 2 is provided with a hole 2a, the diameter of which corresponds to the diameter of the base 4a of the elastic member 40. Further, the facing 3 is also provided with a hole 3a, the diameter of which corresponds to the maximum diameter of the protrusion 4b of the elastic member 4. The elastic member 4 is inserted into the hole 2 of the core plate 2.
The drive plate 1 is constructed by bonding the base portion 4a to the core plate 2a and bonding the facings 3 to both sides of the core plate 2. Note that the facing 3 that should be shown on the right side of the core plate 2 is omitted in the figure.

In a wet multi-plate clutch to which the drive plate 1 configured as described above is applied, the drive plate 1 is provided with an elastic member 4 as described in -F, and the elastic member 4 has a protrusion 2b on the facing 3. Since it protrudes from the surface by the amount of the protrusion, it is possible to prevent the drive plate 1 from falling down when the drive plate 1 is not fastened, and to ensure a clearance Co corresponding to the amount of the protrusion between the drive plate 1 and the driven plate 105. can. Therefore, the drag torque caused by the viscosity of the lubricating oil interposed between the two plates can be reduced, so the power loss of power transmission members such as automatic transmissions to which the wet multi-disc clutch is applied is reduced, and the power The fuel efficiency of a vehicle equipped with the transmission member can be improved.

At this time, the friction coefficient of the elastic member 4 is smaller than that of the facing 3, and the contact area with the driven plate 105 is very small, so the power loss due to the elastic member 4 contacting the driven plate 105 is small. Furthermore, since the elastic member 4 is compressed in the direction of the rotational axis by the adjacent driven plate 105 when the wet multi-plate clutch is engaged, the drive plate 101 and driven plate 105 which do not have the elastic member 4 as in the prior art are used. Rotational force can be transmitted between both plates in the same way as the wet multi-plate clutch.

Here, when using a plate formed by adhering a friction member to a core plate like the drive plate 1 in this embodiment as either the first plate or the second plate, the plate in contact with the elastic member should be If a friction member is provided, the durability of the elastic member is reduced. Therefore, it is preferable to use a plate formed by adhering a ridge friction member to a core plate as the first plate provided with an elastic member because the elastic member has better durability.

Although four elastic members 4 are provided on the drive plate 1 in this embodiment, the number of elastic members 4 is not limited to these.

Further, in the first plate formed by adhering a friction member to the core plate as in this embodiment, 11! Although a configuration in which oil grooves are provided in the friction member is already known, it goes without saying that the present invention may be applied to such a first plate.

(Effect of the invention) As described above, in the present invention, the disk-shaped first
In a wet type multi-disc clutch that transmits rotational force between a plate and a disk-shaped second plate by pressing the two plates, the first plate is provided with an elastic member that contacts the second plate, and the first plate is provided with an elastic member that contacts the second plate. The dimension of the elastic member in the rotation axis direction is larger than the dimension of the first plate in the rotation axis direction, and the friction coefficient of the surface of the elastic member that contacts the second plate is smaller than the friction coefficient of the surface of the first plate. Therefore, a wet multi-disc clutch with reduced power loss can be obtained.

[Brief explanation of the drawing]

Fig. 2 is an exploded perspective view showing the structure of the first plate, Fig. 3 is a sectional view showing the structure of a conventional wet type multi-disc clutch, and Fig. 4 shows the relationship between the drag torque generated between the plates and the clearance C between the plates. It is a figure showing a relationship. 1.101... Drive plate (first plate),
2.102... Core plate, 3,103... Facing (I vibration member), 4... Elastic member, 5°105
...Driven plate (second plate). Patent applicant Nissan Motor Co., Ltd. Figure 1

Claims (1)

[Claims] In a wet multi-disc clutch that transmits rotational force between a disc-shaped first plate and a disc-shaped second plate by pressing them together, the first plate contacts the second plate. An elastic member is provided, and the dimension of the elastic member in the direction of the rotation axis is larger than the dimension of the first plate in the direction of the rotation axis, and the coefficient of friction of the surface of the elastic member in contact with the second plate is equal to the friction of the surface of the first plate. A wet multi-disc clutch characterized by a coefficient smaller than the coefficient.