JPH0118946Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a diaphragm valve device used for, for example, signal negative pressure introduction control in an exhaust gas recirculation system.

Conventionally, the above-mentioned exhaust recirculation control valve has been used to recirculate exhaust gas to the internal combustion engine in proportion to the amount of intake air in the entire operating range of the internal combustion engine, thereby reducing nitrogen oxides and improving fuel efficiency. In order to perform negative pressure control, a diaphragm valve device is used to control a signal negative pressure introduced into the negative pressure chamber.

FIG. 1 is a vertical sectional view specifically showing a conventional example of such a diaphragm valve device, in which a case body 1 includes one head, three case members 1a, 1b,
1c, these are made of synthetic resin,
Each peripheral portion is integrally bonded by adhesive or other method. The case member 1a is provided with a negative pressure introduction passage 2 connected to a negative pressure passage for introducing bench lily negative pressure. Further, the case member 1c is provided with an exhaust pressure introduction passage 3 connected to an exhaust passage of the internal combustion engine. Reference numeral 4 denotes a head having a valve hole 5 in the center vertical direction and an atmosphere venting passage 6 connected to the negative pressure passage communicating with the valve hole 5 and leading to the negative pressure chamber of the reflux control valve, and located in the upper part of the case member 1a. integrally connected at the center. 7, the outer periphery is the case member 1a,
1b, the inner periphery is a head 4, and a ring-shaped first diaphragm is held between the case members 1a;
Reference numeral 8 denotes a second diaphragm having a disk shape whose outer periphery is held between the case members 1b and 1c. The inside is separated.
12, 13, 14 are the first and second diaphragms 7,
The first retainer plate 12 is designed to support both the diaphragms 7 and 8, respectively. 17 is a set spring that urges the second diaphragm 8 upward; 18 is a holding member 1 integrated with the fixing member 16;
This is a rubber valve plate attached to 9. Reference numeral 20 denotes a through hole provided in the wall thickness around the valve hole 5 of the head 4, the lower part of which is connected to the cylindrical portion 21 of the lower part of the valve hole 5.
An adjustment member 22 is inserted through the adjustment member 22, and a set spring 23 is interposed between the lower end surface of the adjustment member 22 and the second diaphragm 8. 24 is a cylindrical part protruding from the center of the upper part of the head 4, and a nut 2 is attached to the outer periphery of the cylindrical part 24.
5 are screwed together, and depending on the screwing amount of this nut 25, the amount of elevation of the adjusting member 22 facing the lower surface thereof can be adjusted, so that the amount of pressing of the second diaphragm 8 by the set spring 23 can be arbitrarily adjusted. It's summery. 26 is a filter through which the outside air and the atmospheric chamber 10 are communicated. 27
28 is a cap that seals the upper end of the valve hole 5, and 28 is a cover that covers the upper end of the head 4.

In such a diaphragm valve device, as described above, the negative pressure introduction passage 2 is connected to the negative pressure passage for introducing the negative pressure from the bench, and the exhaust pressure introduction passage 3 is connected to the intake manifold and the exhaust passage of the internal combustion engine. The atmospheric air outlet passage 6 is connected to the exhaust pressure introduction passage of the connected reflux control valve valve body, and the negative pressure chamber for the reflux control valve. Then, when a bench lily negative pressure, which is an engine substitute characteristic, is introduced into the negative pressure chamber 9 from the negative pressure introduction passage 2, and exhaust pressure is introduced into the exhaust pressure introduction chamber 11, both diaphragms 7,
8 is raised, and the valve plate 19 closes the lower end of the valve hole 5. This blocks the introduction of atmospheric air into the negative pressure chamber of the recirculation control valve through the through hole 6, thereby opening the valve body interposed between the intake manifold and the exhaust passage of the internal combustion engine. Circulate the exhaust gas into the internal combustion engine. As a result, negative pressure as a feedback signal is introduced into the exhaust pressure introduction chamber 11, and both diaphragms 7 and 8 are lowered by the negative pressure, the valve hole 5 for air circulation is opened, and the air is passed through the air hole 6 to the exhaust pressure introduction chamber 11. introduced into a negative pressure chamber. Thus, the valve body for the recirculation control valve closes the exhaust recirculation passage, and the exhaust pressure introduction chamber 11
Positive pressure is introduced into the valve plate 19, and the valve plate 19 acts to close the valve hole 5 again. By repeating this operation, exhaust gas recirculation is controlled. At low speeds and low loads when the amount of intake air is small, the amount of reflux is small, and at high speeds and loads where there is a large amount of intake air, the amount of reflux is large and the engine is running. Overall, exhaust gas recirculation is performed in proportion to the amount of intake air to reduce nitrogen oxides and improve fuel efficiency.

However, in such a conventional diaphragm valve device, the retainer plate and the caulking pin were formed separately, which caused the following drawbacks.

(1) The number of parts increases due to the caulking pin.

(2) It is necessary to insert the caulking pins one by one into the pin holes provided in the retainer plate, etc. In particular, in order to securely clamp the diaphragm between the two retainer plates, it is necessary to insert a large number of caulking pins (usually Since approximately 8 crimping pins must be used, inserting the crimping pins into the pin receiving holes is troublesome.

(3) Furthermore, the crimping pins inserted into the pin receiving holes as described above have to be crimped one by one, which is a cumbersome task.

(4) Furthermore, since the caulking pins are caulked one by one, the amount of caulking for each caulking pin tends to vary, making it difficult to obtain uniform caulking strength.

The present invention provides a diaphragm valve device comprising a diaphragm, a pair of retainer plates for clamping the diaphragm, and a plurality of caulking pins for caulking the pair of retainer plates. By forming bottomed cylindrical protrusions and using these protrusions as the caulking pins, the above-mentioned conventional drawbacks are solved.

Next, the present invention will be explained based on the drawings from FIG. 2 onwards. In the figure, 13 is a second retainer plate, and the second retainer plate 13 is ring-shaped and has a size corresponding to the effective diameter of the first diaphragm 7.
The cross section is shaped like a square. Reference numerals 15 and 15 designate eight caulking pins having the same size and protruding from the center surface 13a of the second retainer plate 13 at regular intervals in the circumferential direction. When the retainer plate 13 is press-molded into a cross-sectional shape, the first diaphragm 7 and the first diaphragm 7 are press-molded at the same time.
It can be inserted into a pin receiving hole provided in the retainer plate 12.

Then, place the first diaphragm 7 on the first retainer plate 12, align the pin receiving holes of the first retainer plate 12 and the first diaphragm 7, and then insert the caulking pins 15, 15 into these pin receiving holes. If you insert it and caulk its tip, the first diaphragm 7 will be connected to the first retainer plate 1.
2 and the second retainer plate 13. A bead portion 7' is provided at the inner peripheral end of the diaphragm 7 to prevent the diaphragm from coming off. In the figure, 29 is a diaphragm that partitions the negative pressure chamber 9 and the atmospheric chamber 10, 30 is a set spring that urges the first and second diaphragms 7 and 8 downward, and 31 is a seat for the set spring 30. The catch seat 31 is formed of a metal plate with three or more claw pieces 31b, 31b projecting radially from a central portion 31a as shown in FIG. By changing the angle, the amount of pressure on the diaphragm by the set spring 30 can be easily adjusted. 32 connects the catch 31 to the valve plate 1
8, a spacer that is clamped to the holding member 19; 33, a spacer that clamps the diaphragm 29 to the spacer 32; and 34, a case member made of stainless steel to prevent it from being damaged by exhaust gas. 1
This is a ring body for attaching c to the case member 1b made of synthetic resin, and the ring body 34 is made of the same thermoplastic synthetic resin as the case member 1b,
By welding 35 to the case member 1b, one end of the stainless steel case member 1c is clamped between the case member 1b and the case member 1b. Note that the same components as those in the conventional example are given the same reference numerals and redundant explanations will be omitted. Further, in the embodiment shown in the drawings, the crimping pins 15, 15 are formed integrally with the second retainer plate 13, but the crimping pins 15, 15 are formed on the first retainer plate 13.
It may be formed integrally with. It goes without saying that the diaphragm valve device is not limited to one used for controlling the signal negative pressure introduction of the exhaust gas recirculation system.

As explained above, the present invention provides a diaphragm valve device including a diaphragm, a pair of retainer plates that clamp the diaphragm, and a plurality of caulking pins that caulk and connect the pair of retainer plates. A plurality of bottomed cylindrical protrusions are formed on either side,
Since these protrusions are used as the caulking pins, the following effects can be obtained.

(1) Since the retainer plate and caulking pin are integrated, the number of parts is reduced accordingly.

(2) Multiple caulking pins can be simultaneously inserted into pin receiving holes provided in the diaphragm, etc.

(3) A large number of crimping pins can be crimped simultaneously and with uniform force using a press.

(4) Since the caulking pin is formed into a cylindrical shape with a bottom, it prevents the tip of the caulking pin from unnecessarily deforming or expanding in diameter before use (before caulking). When you crimp the tip,
The bottom plate of the tip overlaps above the flange part, and the flange part and the bottom plate double suppress the surface of the other retainer plate, thereby increasing the bonding strength between the retainer plates.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional example, Fig. 2 is a sectional view showing an example of the present invention, Fig. 3 is a perspective view of a retainer plate integrally formed with a riveting pin, and Fig.
5 is a perspective view of the seat of the set spring, and FIG. 6 is an enlarged view of the main parts. 7, 8... diaphragm, 12, 13, 14...
...retainer plate, 15...caulking pin.

Claims (1)

[Scope of utility model registration request] In a diaphragm valve device comprising a diaphragm, a pair of retainer plates that clamp the diaphragm, and a plurality of caulking pins that caulk and connect the pair of retainer plates, the plurality of caulking pins are formed on either one of the retainer plates. A diaphragm valve device characterized by having a cylindrical connection protrusion with a bottom.