JP2572866Y2 - Diaphragm actuator - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a diaphragm actuator. The diaphragm actuator of the present invention is used for an automatic transmission or the like.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 2 and 3, a caulking portion 4 is provided on a case 1 as a diaphragm actuator.
Is known in which the outer peripheral edge portion 6 is crimped. Case 1 consists of upper case 2 and lower case 3,
A caulking portion 4 is provided at the joint between the two.

[0003]

Conventionally, the diaphragm 5 is formed of hydrin rubber. Hydrin rubber is excellent in bending resistance, and is frequently used as a material of the diaphragm 5 for this reason.
There is a drawback that the compression set at a high temperature is large, and the repulsive force of the crimped portion in the crimping portion 4 decreases with the passage of time, which causes an airtight leak or the upper case 2 and the lower case However, there is a problem in that although it must be firmly joined to the base 3 by simply turning it by hand, it can be easily turned. The diaphragm 5 may be formed of fluorosilicone rubber. Fluorosilicone rubber has a characteristic of a small compression set, and thus can eliminate the disadvantages of the diaphragm 5 made of hydrin rubber. However, this fluorosilicone rubber has a drawback that it has poor bending resistance, and has a problem that a crack occurs in the movable portion 7 of the diaphragm 5 during operation, resulting in airtight leakage.

[0004]

SUMMARY OF THE INVENTION In view of the above points, the present invention has been devised to solve the above-mentioned problems in the prior art, and has been provided in a case to achieve this object. A caulking portion and an outer periphery caulked by the caulking portion
Edge and a movable portion that is integrally formed on the inner peripheral side of the outer peripheral edge, a diaphragm molded by excellent rubber across the bending resistance, the disposed further outer peripheral side of the outer peripheral edge portion Caulked by the caulking part together with the outer periphery ,
Rings made of rubber with a low compression set
The ring has an axial width in a free state,
Set larger than the axial width in the free state of the outer peripheral edge
It is to provide a diaphragm actuator, characterized in that.

[0005]

The entire diaphragm is formed of rubber having excellent bending resistance, for example, hydrin rubber, so that a crack is not generated in a movable portion of the diaphragm during operation. Further on the outer peripheral side of the outer peripheral edge portion of the diaphragm in the caulking portion of the case, a small rubber compression set ratio, for example by placing a ring molded by fluorosilicone silicone rubber, the crimped portion of the ring with the outer peripheral edge of the diaphragm It is fixed by caulking so that the repulsive force against the caulked portion does not decrease over time. Also this compression set
Axial width of rubber ring with low modulus in free state
The axial direction in the free state of the outer peripheral edge of the diaphragms
This ring is larger than the
Relatively large compression by crimping from the outer edge of the flam
Is done. Therefore, the great rebound that occurs with this
Force causes airtight leakage and loose joints at the swaged part
Can be effectively prevented over a long period of time.
In addition, the compression of the outer peripheral edge of the diaphragm is relatively small.
Large caulking force on this outer edge
It does not work continuously, so this outer peripheral edge becomes prematurely fatigued.
Can be effectively prevented.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

As shown in FIG. 1, a caulking portion 4 is provided in a case 1 composed of an upper case 2 and a lower case 3, and the outer peripheral edge 6 of the diaphragm 5 is caulked in the caulking portion 4. The diaphragm 5 has its outer peripheral edge
All parts including the part 6 and the movable part 7 are formed of rubber having excellent bending resistance such as hydrin rubber. Further, a ring 8 made of rubber having a low compression set such as fluorosilicone rubber is interposed on the outer peripheral edge 6 of the diaphragm 5 in the caulking portion 4. The axial width of the ring 8 in the free state is the outer peripheral edge of the diaphragm 5.
The width of the portion 6 in the free state is made wider than the axial width, and the ring 8 is compressed more by caulking. Compression of the outer peripheral edge portion 6 of the diaphragm 5 is of the order to be retained is the outer peripheral edge portion 6.

[0008] The diaphragm actuator having the above configuration has the following functions and effects. That is, since the entire diaphragm 5 is formed of rubber having excellent bending resistance, it is possible to effectively prevent the movable portion 7 of the diaphragm 5 from being cracked during operation. Further, since the entire diaphragm 5 is formed of one type of rubber, there is no need to embed a shape retaining ring (not shown) in the outer peripheral edge portion 6, and extra time is required for vulcanization molding of rubber. Nothing. Further, on the caulking portion 4 of the case 1, a ring 8 formed of rubber having a small compression set is arranged on the outer peripheral side of the outer peripheral edge 6 of the diaphragm 5, and this ring 8 is attached to the outer peripheral edge of the diaphragm 5. 6 and the caulking portion 4 is fixed by caulking, so that the repulsive force against the caulking portion 4 does not decrease even after a lapse of time. This ring 8 is also formed of one kind of rubber, so that the molding does not take much trouble.

[0009]

[Effects of the Invention] The present invention has the following effects. That is, in the diaphragm actuator of the present invention having the above configuration, since the entire diaphragm is formed of rubber having excellent bending resistance, it is possible to effectively prevent the movable portion of the diaphragm from being cracked during operation. can do. Further, since the entire diaphragm is formed of one type of rubber, there is no need to bury a shape retaining ring in the outer peripheral portion, and no extra labor is required for vulcanization molding of rubber. Further, on the caulking portion of the case, on the outer peripheral side of the outer peripheral edge portion of the diaphragm, a ring formed of rubber having a small compression set is arranged,
Since this ring is fixed by caulking together with the outer peripheral edge of the diaphragm, the repulsive force against the caulking portion does not decrease even after a lapse of time. This ring is also formed of one kind of rubber, so that the molding does not take much trouble. Also this compression
Axle in free state of rubber ring with low permanent set.
The axis in the free state of the outer peripheral edge of the diaphragm with the direction width
Of the ring
Is more crimped than the outer edge of the diaphragm
Largely compressed. Therefore, it occurs with this
Large repulsion force causes leaks and loose joints
Can be effectively prevented over a long period of time
The compression of the outer peripheral edge of the diaphragm is relatively small.
Large crimping force is applied to this outer peripheral edge
Does not work continuously, so this outer edge
Early fatigue can be effectively prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a diaphragm actuator according to an embodiment of the present invention.

FIG. 2 is a partially cutaway front view showing the entire structure of the diaphragm actuator.

FIG. 3 is a sectional view of a main part of a diaphragm actuator according to a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Case 2 Upper case 3 Lower case 4 Caulking part 5 Diaphragm 6 Outer periphery 7 Movable part 8 Ring

Claims (1)

(57) [Scope of request for utility model registration] 1. A caulking portion (4) provided on a case (1), an outer peripheral edge (6) caulked by the caulking portion (4) and an inner peripheral side of the outer peripheral edge (6). It is provided with a movable part (7), a diaphragm molded by excellent rubber entire bending resistance (5), the outer periphery is further disposed on the outer peripheral side of the outer peripheral edge portion (6)
Caulked by the caulking portion (4) together with the edge (6),
A ring (8) formed of a rubber having a small compression set , wherein the axial width of the ring (8) in a free state is the same as that of the ring (8).
Larger than the axial width of the outer peripheral edge (6) in the free state
A diaphragm actuator characterized by being set .