JPH054576Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a wet multi-disc clutch or brake.

(b) Prior Art A conventional wet type multi-disc clutch is disclosed, for example, in Japanese Patent Application Laid-open No. 140925/1983. This wet type multi-plate clutch has a plurality of first clutch plates having splines on the outer periphery and second clutch plates having splines on the inner periphery, which are alternately stacked one on top of the other. Splines on the first clutch plate engage internal splines integral with the clutch drum, and splines on the second clutch plate engage external splines on other rotating members. A pressing force can be applied to the first clutch plate and the second clutch plate by a piston, or this pressing force can be released. This allows the clutch to be engaged and released.

(c) Problems to be solved by the invention However, such conventional wet-type multi-plate clutches suffer from large friction losses during idling when the clutch is in an open state, and in some cases, the clutch plates may burn out. be. In other words, in the wet multi-plate clutch as described above, when the pressing force from the piston is released, no positive force is applied to separate the clutch plates from each other, but the viscosity of the oil interposed between the clutch plates causes the clutch plates to separate. The drag torque between the plates has increased, and the friction loss in the wet multi-plate clutch has increased. Additionally, in some cases, the clutch plate was burnt out due to heat generated by friction.

In addition, Japanese Utility Model Application No. 61-73926 discloses, as a separating means for separating the clutch plates, a leaf spring whose one end is fixed to one side of the claw part of the driven plate and is inclined in the shape of a single roof, and a driven plate. A cut-and-raised portion is shown, which is cut in a U-shape at a position where it overlaps with an adjacent driven plate, and is sloped in the shape of a single roof. When the multi-plate clutch is released, the restoring force of the leaf spring or cut-and-raised portion allows adjacent driven plates to be separated at an appropriate distance.

In addition, Japanese Patent Application Laid-open No. 17756/1983 discloses that cut and raised tongues formed at predetermined intervals in the circumferential direction of a ring-shaped leaf spring provided on the outer periphery of a friction plate and ring-shaped leaf springs are wave-shaped. A device is shown in which the pressure plate and the friction plate are constantly separated from each other by spring characteristics such as those formed in the above-described example.

However, although the two disclosed in the above-mentioned publications can solve the problems of the conventional wet multi-plate clutch described above, there are other problems as follows. In other words, in the device disclosed in Japanese Utility Model Application Publication No. 61-73926, the reaction force of the leaf spring and the cut-and-raised portion changes continuously with respect to displacement, so when the driven plates and the friction plates are normal, There is a problem in that when you try to get closer than that, you cannot pull away because of the stronger reaction force.

What is shown in Japanese Patent Application Laid-Open No. 51-17756 is
The spring characteristics of the lifting tongue and ring-shaped plate spring formed in a wave shape also change continuously in response to displacement, so they are also stronger when the friction plates try to approach each other than in the normal case. The problem is that it cannot be pulled apart by reaction force.

The present invention aims to solve these problems.

(d) Means for Solving the Problems The present invention solves the above problems by providing a leaf spring that rapidly increases the force that separates the clutch plates when they approach each other more than a predetermined value. That is, the wet multi-disc clutch or brake according to the present invention is provided with a leaf spring that applies a force to the first clutch plate or the second clutch plate to move the first clutch plates or the second clutch plates away from each other. The spring has a substantially dogleg shape, one end of which is fixed to the first clutch plate or the second clutch plate,
The other end side is separated from the first clutch plate or the second clutch plate, and is arranged so as to be able to come into contact with the adjacent first clutch plate or second clutch plate at a substantially dogleg-shaped bent part, The leaf spring is moved to a position where the other end of the leaf spring comes into contact with the first clutch plate or second clutch plate on which the leaf spring is installed by relative displacement of the adjacent first clutch plate or second clutch plate in the direction toward each other. The leaf spring must be capable of displacement, and generate a larger reaction force when the other end of the leaf spring is in contact with the first clutch plate or the second clutch plate than when the leaf spring is separated from the first clutch plate or the second clutch plate. It is characterized by

(E) Function For example, since a leaf spring is provided between each first clutch plate, the gap between each first clutch plate is maintained at a predetermined state when the clutch is released. As a result, the second clutch plate existing in the gap between the first clutch plates becomes free within this gap, and the friction between the clutch plates during idling is reduced. In this state, for example, if force is applied from the piston due to hydraulic pressure generated by centrifugal force and attempts to bring the first clutch plates closer together than usual, the other end of the leaf spring Contact the clutch plate. As a result, the spring characteristics change and a larger reaction force is generated, thereby reliably preventing the first clutch plate and the second clutch plate from coming into close contact with each other. This reduces friction losses in wet multi-plate clutches or brakes and improves the durability of the clutch plates.

(F) Example (First Example) An example of the present invention is shown in FIGS. 1 to 3. Rotatably supported clutch drum 10 (one member)
A piston 12, a return spring 14, a first clutch plate 16, a second clutch plate 18, a retainer plate 20, and a snap ring 22 are arranged therein as shown. 1st of 3 each
The clutch plates 16 and the second clutch plates 18 are arranged alternately one on top of the other. The splines 16a on the outer diameter of the first clutch plate 16 mesh with the inner splines 10a of the clutch drum 10, and the first clutch plate 16 rotates together with the clutch drum 10. On the other hand, the spline 18a on the inner diameter of the second clutch plate 18
is engaged with the outer diameter spline 24a of the rotating member 24 (the other member), and the second clutch plate 18 rotates together with the rotating member 24. A leaf spring 28 is provided on the side surface of the spline 16a of the first clutch plate 16. The leaf spring 28, as shown in FIGS. 2 and 3,
It is made by bending the center part of a plate-shaped member, and the bent part has a roughly dogleg shape, one end of which is integrated with the plate-shaped member, and the other end is The bent portion 28a is in a state separated from the main body of the plate-like member, and the bent portion 28a is in a state farthest from the main body of the plate-like member. Note that the leaf spring 28 can also be formed integrally with the base material of the first clutch plate 16.

In the wet type multi-plate clutch as described above, when a pressing force is applied by the piston 12, the first clutch plate 16 and the second clutch plate 18 are fastened by frictional force, and the clutch drum 10 and the rotating member 24 are connected. It becomes possible to transmit force in the rotational direction between the two. Conversely, when the piston 12 is deactivated,
The clutch drum 10 and rotating member 24 are separated. In this released state, the clutch drum 10 and the rotating member 24 rotate relative to each other. That is, the first
Clutch plate 16 and second clutch plate 1
8, a relative rotation will occur between the two. In this state where the pressing force of the piston 12 is released, the first clutch plates 16 are separated from each other by the elastic force of the leaf spring 28, and a gap is formed thereby. The second clutch plate 18 located at
kept out of contact with. From this state,
The direction in which the first clutch plates 16 are brought closer to each other due to some reason (for example, when a centrifugal force is applied to the oil due to the rotation of the clutch drum 10 and a relatively small hydraulic pressure is applied to the piston 12). When a force is applied, the leaf spring 28 is displaced and its tip contacts the first clutch plate 16. As a result, the leaf spring 28 changes from a cantilevered state to a state where it is supported at both ends, so the spline characteristics change rapidly and a larger reaction force is generated.
Therefore, since the first clutch plates 16 are reliably prevented from coming close to each other more than a predetermined value,
Clutch plate 16 and second clutch plate 1
8 and is always kept separated. Therefore, even if the first clutch plate 16 and the second clutch plate 18 rotate relative to each other at high speed, almost no frictional force is generated between them. This reduces friction loss when the clutch drum 10 and rotating member 24 rotate relative to each other. Furthermore, since heat generation due to friction is reduced, the first clutch plate 16 and the second clutch plate 18 are prevented from burning out. Since the leaf spring 28 contacts the clutch plate 16 at the rounded bent portion 28a, the contact becomes smooth and wear resistance is improved.

In the described embodiment, the first clutch plate 16 is provided with a leaf spring, but the same action and effect can be obtained even if the leaf spring is provided on the second clutch plate 18.

(g) Effects of the invention As explained above, according to the invention, the leaf spring generates a larger reaction force when its tip is in contact with the clutch plate than when it is separated from the clutch plate. Since this is provided on the clutch plate, it is possible to reliably secure a clearance between the first clutch plate and the second clutch plate when the clutch is released, thereby reducing friction loss. Further, the durability of the clutch plates can be improved, and seizing of the clutch plates to each other can be reliably prevented.

[Brief explanation of drawings]

FIG. 1 is a view showing an embodiment of the present invention, FIG. 2 is an enlarged view of a leaf spring portion, and FIG. 3 is a view seen in the direction of arrow III in FIG. 2. 10...Clutch drum (one member), 12
... Piston, 16 ... First clutch plate,
18... Second clutch drum, 24... Rotating member (other member), 28... Leaf spring, 28
a...Bending part.

Claims (1)

[Claims for Utility Model Registration] A plurality of first clutch plates 16 that are restrained in the rotational direction with respect to one member 10, and a plurality of second clutch plates 18 that are restrained in the rotational direction with respect to the other member 24. By arranging the clutch plates alternately on top of each other and applying or deactivating the pressing force of the piston 12 between both clutch plates, one member and the other member can be connected or disconnected in the rotational direction. A leaf spring 2 that exerts a force on the first clutch plate 16 or the second clutch plate 18 to move the first clutch plates 16 away from each other or the second clutch plates 18 from each other.
8, the leaf spring 28 has a substantially doglegged shape, and one end of the leaf spring 28 is connected to the first clutch plate 16 or the second clutch plate 18. fixed, with the other end separated from the first clutch plate 16 or the second clutch plate 18,
The leaf spring 28 is arranged so as to be able to come into contact with the adjacent first clutch plate 16 or the second clutch plate 18 at the approximately dogleg-shaped bent portion 28a.
6 or the second clutch plate 18 in the direction toward each other, the leaf spring 28
The other end of the leaf spring 28 is movable to a position where it contacts the first clutch plate 16 or the second clutch plate 18 on which it is provided.
Alternatively, a wet multi-disc clutch or brake is characterized in that it generates a larger reaction force when it is in contact with the second clutch plate 18 than when it is in a detached state.