JPH0446082Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a multi-stage actuator using a diaphragm.

Conventionally, this type of actuator has been known to use a plurality of diaphragms to move a rod attached to the diaphragms, but this has the disadvantage of having a complicated structure.

In addition, as shown in Japanese Patent Application Laid-Open No. 52-107474, there are some cases in which the number of diaphragms is one, but in this actuator (vacuum driver), the vacuum inlet of the piston valve 13 is 1
1 does not open at the end surface of the piston valve 13, but the introduction hole 14 opens at the circumferential surface of the piston valve 13 and is closed by the inward protrusions of the seal members 17 and 19. Therefore, the inward protrusions of the seal members 17 and 19 are connected to the through hole 14.
This has the problem that early deterioration of sealing performance is unavoidable because the seal is damaged by being scratched by the edge of the seal.

The present invention aims to solve the problems found in the above-mentioned conventional techniques.

In order to achieve the above object, the present invention provides first and second cases that are coupled to each other with an internal cavity, and a second case that is sandwiched between the first and second cases.
a diaphragm forming a negative pressure chamber between the case and the second case, and a spring disposed within the negative pressure chamber to bias the diaphragm; An actuator that moves the diaphragm and a rod fixed to the diaphragm using a pressure difference between a negative pressure introduced into a chamber and an atmospheric pressure introduced into the air chamber, and the elastic force of the spring. A valve member made of a rubber-like elastic material and formed into a substantially cylindrical shape with a bottom and having an inward seal protrusion at the opening end of the recess is attached to the negative pressure chamber side, and the valve member is attached to the first case. is provided with a negative pressure introduction hole having a substantially cylindrical shape and opening at the tip face at a position facing the valve member, and a first nipple that causes the tip portion to protrude toward the seal protrusion side is screwed into the hole, and A contact portion with the seal protrusion and a sliding contact portion between the circumferential surface of the first nipple and the seal protrusion are both formed as smooth surfaces, and a second nipple communicating with the negative pressure chamber is attached.

When the actuator of the present invention having the above-mentioned configuration is used, the first nipple screwed into the center of the first case is connected to the negative pressure generating part of the mechanical device to be adjusted, and the second nipple is connected to the negative pressure generating part of the mechanical device to be adjusted. The nipple is exposed to the atmosphere through an orifice with a minute inner diameter.

When the negative pressure in the negative pressure chamber is reduced by the negative pressure passing through the first nipple, and the suction force against the diaphragm exceeds the pressing force by the spring, the diaphragm approaches the first nipple, and the seal protrusion of the valve member and the first nipple The diaphragm and rod are stopped while the amount of air sucked out through the gap with the tip of the nipple and the amount of air sent into the negative pressure chamber through the orifice connected to the second nipple are balanced. kept in condition.

When the inward seal protrusion of the valve member and the tip of the first nipple come into contact with each other and the negative pressure introduction hole of the first nipple is closed, the large volume supplied via the orifice connected to the second nipple is The pressure inside the negative pressure chamber increases due to the atmospheric pressure, and the diaphragm is pushed by the spring and moves toward the second case, breaking contact between the first nipple and the seal protrusion of the valve member, and depressurizing the negative pressure chamber again. to cause the diaphragm and rod to move again.

The stopping position of the diaphragm and the rod as the tip of the first nipple and the seal protrusion of the valve member approach each other is determined by the amount of protrusion of the first nipple with respect to the first case. Adjustment is made by adjusting the threaded engagement portion of the member.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a partial front sectional view of the first embodiment of the present invention, in which the outer peripheral edge of the diaphragm 3 is sandwiched between the opening edges 1a and 2a of the first case 1 and the second case 2, and the first A negative pressure chamber 4 is formed between the case 1 and the diaphragm 3, and an air chamber 5 communicating with the atmosphere is formed between the second case 2 and the diaphragm 3. 2. One end of a rod 6 passing through the central hole 2b of the case 2 is fixed.

A central hole 2b is provided on the negative pressure chamber 4 side of the diaphragm 3.
A guide member 9 is disposed in the center of the guide member 9, and a recess 7a formed of a rubber-like elastic material and having a depth d is provided in the center of the guide member 9. A bottomed cylindrical valve member 7 having a protruding seal protrusion 7b is fixed thereto, and a negative pressure introduction member having a substantially cylindrical shape and opening at a tip end face 8b is installed at a position facing the valve member 7 of the first case 1. hole 8c
The first nipple 8 having a first nipple 8 is screwed onto the tip surface 8b and the sealing protrusion 7b while keeping a distance d ^- between the tip surface 8b and the sealing protrusion 7b. In addition, the contact portion between the circumferential surface of the first nipple 8 and the seal protrusion 7b is formed into a smooth surface, and the second case 1 is connected to the negative pressure chamber 4.
A nipple 10 is attached, and a spring 11 is interposed between the guide member 9 and the first case 1, thus configuring this embodiment.

2 and 3 are enlarged cross-sectional views of essential parts showing operating conditions of the valve member 7 in the actuator of the present invention configured as described above, and FIG. 2 shows a state in which negative pressure is introduced into the negative pressure chamber 4. First, a case is shown in which there is no pressure difference between the inside of the negative pressure chamber 4 and the inside of the air chamber 5, and the diaphragm 3 is supported by the second case 2 and the tip surface 8b of the first nipple 8 and the valve member 7 are A distance d ^- is maintained between the seal projection 7b and the seal projection 7b.

In FIG. 3, the first nipple 8 is connected to the negative pressure generating part of the mechanical device to be used, and the second nipple 10 is opened to the atmosphere through an orifice with a minute inner diameter (not shown), and the pressure inside the negative pressure chamber 4 is reduced. The pressing force due to the pressure difference with the inside of the air chamber 5 exceeds the elastic force of the spring 11, the diaphragm 3 moves toward the first nipple 8, and the tip 8a of the first nipple 8 touches the valve member 7.
This figure shows a case where the negative pressure introduction hole 8c of the first nipple 8 is closed by contacting the seal protrusion 7b.

In this case, the negative pressure passing through the first nipple 8 is cut off, and the negative pressure in the negative pressure chamber 4 is reduced by air sent through an orifice with a minute inner diameter (not shown) connected to the second nipple 10. The pressure decreases (in the direction of becoming close to atmospheric pressure), weakening the suction force on the diaphragm 3, so the diaphragm 3 moves toward the air chamber 5 side, and the contact between the negative pressure introduction hole 8c and the seal protrusion 7b disappears, and the negative pressure is introduced. The hole 8c is unblocked, and negative pressure is again introduced into the negative pressure chamber 4 through the tip 8a of the first nipple 8.

Therefore, the diaphragm 3 is again connected to the first nipple 8.
Move to the side.

After repeating the above, the amount of air sent through an orifice with a minute inner diameter (not shown) and the negative pressure introduction hole 8c
The amount of air flowing out is balanced with each other, and the diaphragm 3 and the rod 6 are kept in a stopped state.

This completes the first stage of operation.

Next, the first nipple 8 is closed and the second nipple 1 is closed.
0 is switched to introduce a predetermined negative pressure sufficient to compress the spring 11, the diaphragm 3 moves together with the rod 6 toward the first nipple 8 due to the pressure difference between the negative pressure chamber 4 and the air chamber 5.

This completes the second stage of operation.

However, the maximum amount of movement of the diaphragm 3 toward the first nipple 8 is between the edge of the guide member 9 attached to the diaphragm 3 on the first nipple 8 side and the first case 1.
is regulated by contact with the stepped portion on the negative pressure chamber 4 side.

Next, a second embodiment of the present invention will be described with reference to FIGS. 4 and 5.

This example is based on the first example above, except for the points described below.
It has the same configuration as the embodiment.

That is, on the negative pressure chamber 4 side of the first case 1, a first seal ring 12 made of a gasoline-resistant resin material such as fluorine or nylon and a second seal ring 13 made of a rubber-like elastic material are attached to the first seal ring 1.
2 is arranged and attached to the diaphragm 3 side, and the second seal ring 13 ensures the sealing performance of the threaded part of the first nipple 8 and the first case 1, and it is introduced into the negative pressure chamber 4. The first seal ring 12 prevents the gasoline atmosphere from entering the second seal ring 13 side, thereby preventing swelling of the second seal ring 13, and also prevents displacement of the first nipple 8 during operation. This is suppressed by elastically holding the first nipple 8.

As described in detail above, the actuator of the present invention has first and second parts coupled to each other and having an internal cavity.
a second case, a diaphragm sandwiched between the first and second cases to form a negative pressure chamber with the first case and an air chamber with the second case; and a diaphragm that forms a negative pressure chamber with the second case; A spring is disposed inside the chamber and biases the diaphragm, and due to the pressure difference between the negative pressure introduced into the negative pressure chamber and the atmospheric pressure introduced into the air chamber, and the elastic force of the spring, the An actuator for moving a diaphragm and a rod fixed to the diaphragm,
A valve member is attached to the negative pressure chamber side of the diaphragm, the valve member is made of a rubber-like elastic material and is formed into a bottomed, substantially cylindrical shape, and has an inward seal protrusion at an end on the opening side of the recess; A negative pressure introduction hole having a substantially cylindrical shape and opening at a tip end is provided at a position facing the valve member of the first case, and a first nipple having a tip end protruding toward the seal protrusion side is screwed to the first case; A contact portion between the tip surface and the seal protrusion and a sliding contact portion between the circumferential surface of the first nipple and the seal protrusion are both formed as smooth surfaces, and a second nipple communicating with the negative pressure chamber is provided. By this,
When opening and closing the negative pressure introduction hole of the first nipple, there is no scratching effect on the tip surface of the first nipple and the seal protrusion that comes into contact with the tip.
Since there is no risk of deterioration of sealing performance due to damage to the seal protrusion, the actuator can maintain its normal function for a long period of time, so the practical effect is extremely large.

[Brief explanation of the drawing]

FIG. 1 is a partial front sectional view of an actuator according to a first embodiment of the present invention, and FIGS. 2 and 3 are
FIG. 4 is a partial front sectional view of an actuator according to the second embodiment of the present invention, and FIG. 5 is an enlarged cross-sectional view of the main parts of the same embodiment. It is a diagram. 1...First case, 1a...Opening edge, 2...
First case, 2a...Opening edge, 2b...Central hole, 3...Diaphragm, 4...Negative pressure chamber, 5...
Air chamber, 6... Rod, 7... Valve member, 7a...
... recess, 7b... seal protrusion, 8... first nipple, 8a... tip, 8b... tip surface, 8c...
Negative pressure introduction hole, 9... guide member, 9a... guide hole,
10...Second nipple, 11...Spring, 12...
1st seal ring, 13...2nd seal ring.

Claims (1)

[Scope of utility model registration request] a first and a second coupled to each other with an internal cavity;
Cases 1 and 2 are sandwiched between the first and second cases 1 and 2 to form a negative pressure chamber 4 with the first case 1, and an air chamber 5 with the second case 2.
It has a diaphragm 3 forming a diaphragm 3 and a spring 11 disposed in the negative pressure chamber 4 to bias the diaphragm 3. In the actuator that moves the diaphragm 3 and the rod 6 fixed to the diaphragm 3 by the pressure difference between the atmospheric pressures and the elastic force of the spring 11, a rubber-like elastic member is attached to the negative pressure chamber 4 side of the diaphragm 3. A valve member 7 formed of material into a substantially cylindrical shape with a bottom and having an inward seal protrusion 7b attached to the open end of the recess 7a is attached to the valve member 7 of the first case 1. A negative pressure introduction hole 8 having a substantially cylindrical shape and opening at the tip surface 8b is located opposite to the
c, and a first nipple 8 that projects the tip 8a toward the seal protrusion 7b is screwed on, and the contact portion between the tip surface 8b and the seal protrusion 7b, the circumferential surface of the first nipple 8, and the seal The actuator is provided with a second nipple 10 that communicates with the negative pressure chamber 4 and has a smooth surface on which it slides in contact with the protrusion 7b.