JPH10302591A - Pressure switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure switch in which weight is lightened and fitting in a single operation becomes possible by forming first body and second body of a resin, and simultaneously no hindrance of molding performance of the first and the second bodies is brought about at all. SOLUTION: By fitting the fitting portions 4, 7 of first body 1 and second body 6 mutually so as to engage the protrusion portion 5 of the first body 1 with the recessed portion 8 of the second body 6, the first and the second bodies 1, 6 can be assembled sandwiching the outer periphery of a diaphragm 9 with one touch. Although the protrusion portion 5 of the first body 1 are radially arranged uniformly in the peripheral direction, drafts are formed against forming molds 14, 15 for mold releasing on the peripheral direction both side portions 5a, 5b of the protrusion portions 5. Therefore, no hindrance of mold releasing at the molding time of the first body 1 is brought about at all.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure switch which is used in, for example, an automobile and which is turned on / off by a negative pressure or a positive pressure.

[0002]

2. Description of the Related Art A first body and a second body are fitted and mounted with an outer peripheral portion of a diaphragm interposed therebetween, and two pressure action chambers are separated by a diaphragm inside the first body and the second body. 2. Description of the Related Art A pressure switch in which a fixed contact is provided in a first body of a working chamber and a movable contact which is in contact with or separated from the fixed contact by a pressure difference between internal pressures of two pressure working chambers in a diaphragm is well known.

[0003]

However, in the conventional pressure switch, the first and second bodies are made of metal in order to mount the body on a vehicle body side member and to ground the body.
Since the first and second bodies need to be caulked to clamp the diaphragm, not only the assembly equipment is required, which is disadvantageous not only in cost but also in weight. I will.

For this reason, for example, as shown in FIG. 4, the first and second bodies 41 and 46 are molded from a synthetic resin material, and the first and second bodies 41 and 46 are fitted to each other. It is conceivable that the fitting part 45 and the concave part 48 of the fitting part can be assembled with one touch by engagement.

Specifically, a housing hole 42 is formed at one end of the first body 41, and a connector lock portion 43 for engaging an external connector (not shown) is provided on the outer peripheral surface of the one end, and the other end is provided. A cylindrical fitting portion 44 is formed in the
A plurality of convex portions 45 are provided so as to be radially equally distributed in the circumferential direction on the outer peripheral surface of the.

The second body 46 has a cylindrical fitting portion 4 at one end.
7 are formed, and a plurality of concave portions 48 are equally arranged in the circumferential direction on the inner peripheral surface of the fitting portion 47 in correspondence with the convex portions 45 of the first body 1.

The diaphragm 49 is formed of insulating rubber into a shape to be accommodated inside the fitting portion 47 of the second body 46, and has two fixing members for a positive electrode and a negative electrode (not shown) on the upper surface at the center. Cup-shaped movable contact 50 that contacts and separates from the contact
Is fixed, the first and second bodies 41 and 46 are fitted with the peripheral edge of the diaphragm 49 interposed therebetween, and the convex portion 45 and the concave portion 48 are engaged with each other so as to be assembled with one touch.

However, when the first and second bodies 41 and 46 are made of resin as described above, the first
When the body 41 is molded, as shown in FIG.
It is necessary to divide the mold so that it can be opened in the left and right directions indicated by arrows X1 and X2.

In order to secure the airtightness by uniformly compressing the outer peripheral portion of the diaphragm 49 by the fitting portions 44 and 47 of the first and second bodies 41 and 46, for example, six convex portions 45 are formed radially. When the molds 51 and 52 are equally spaced in the circumferential direction,
The corners 45 a, 45 b, 45 that are undercut when the molds 51, 52 are opened are provided on the projections 45 other than the projections 45 positioned at the divided surfaces 53, 54 when the mold is opened.
c and 45d are generated, the die cannot be cut out, and it cannot be easily adopted.

Therefore, the present invention makes it possible to reduce the weight of the first body and the second body by using resin and to assemble them one-touch, and to hinder the moldability of the first and second bodies. There is no pressure switch to try to provide.

[0011]

According to a first aspect of the present invention, a first body and a second body made of a synthetic resin material are fitted and mounted coaxially with an outer peripheral portion of the diaphragm interposed therebetween. A first pressure action chamber and a second pressure action chamber are separated inside the first body and the second body, and a first pressure action chamber is separated from the first pressure action chamber.
A structure in which two fixed contacts for a positive electrode and a negative electrode are provided on a body, and a movable contact which comes into contact with or separates from the fixed contact by a pressure difference between internal pressures of first and second pressure action chambers is provided on a diaphragm. A plurality of convex portions engaging with the concave portions provided in the fitting portion of the second body are radially equally arranged on the outer peripheral surface of the fitting portion of the first body in the circumferential direction. On both sides in the circumferential direction, a draft is formed on a mold divided so as to be openable in one direction so that the mold can be opened when the mold is opened.

According to the structure of the first aspect, the first body is provided with two fixed contacts for the positive electrode and the negative electrode which come into contact with and separate from the movable contact attached to the diaphragm, and are provided on the second body side with respect to the diaphragm. Since conduction is not required, it is possible to reduce the number of control points for conduction. Of course, since the first and second bodies are made of synthetic resin, the moldability is good, the cost is advantageously obtained, and the weight is low. Can be achieved.

The first body and the second body are fitted to each other, and the projections of the first body are engaged with the recesses of the second body, so that the first and second bodies are sandwiched by the outer periphery of the diaphragm. Since the body can be assembled with one touch, the assemblability can be further improved.

Further, since a plurality of protrusions of the first body are formed on both sides in the circumferential direction with respect to the die from the molding die, the protrusions are formed radially on the outer peripheral surface of the first body. Even if it protrudes, there is no hindrance to the die removal during the molding.

Further, since the convex portions of the first body are radially equally arranged in the circumferential direction and are engaged with the concave portions of the second body, the outer periphery of the diaphragm is formed by the first and second bodies. Since the entire circumference of the portion can be uniformly compressed and clamped, the airtightness of the fitting portion between the first and second bodies can be improved.

A second aspect of the present invention is characterized in that the plurality of projections according to the first aspect have the same area.

According to the structure of the second aspect, since the plurality of projections 5 are formed to have the same area, the projections and the recesses are engaged with each other to engage the first and second bodies with each other. When the outer peripheral portion of the diaphragm is compressed and sandwiched by the above, the reaction force due to the resilient elasticity from the diaphragm can be uniformly borne at the engagement portion between each convex portion and the concave portion, and the first and second bodies are fitted. The airtightness of the part can be further improved.

[0018]

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

1 to 3 show an embodiment, and FIG.
FIG. 2 shows a cross section of the fitting portion 4 of the body 1 and the molds 14 and 15 thereof along the lateral direction. FIG. 2 shows the appearance of the first and second bodies 1 and 6 and the diaphragm 9. 3 shows a cross section of the pressure switch cut along the longitudinal direction.

As shown in FIG. 2, the first body 1 is formed of a synthetic resin material having an insulating property, and a connector lock portion 3 is provided on an outer peripheral surface of one end where a housing hole 2 is formed, and on the other end. On the outer peripheral surface of the formed cylindrical fitting portion 4, a plurality of convex portions 5 are provided radially equally spaced in the circumferential direction.

The second body 6 is formed of a synthetic resin material having an insulating property, and a plurality of concave portions 8 are formed in a cylindrical fitting portion 7 formed at one end portion so as to correspond to the convex portions 5 of the first body 1. It is equally spaced in the circumferential direction and formed through.

The diaphragm 9 is formed in a shape to be accommodated inside the fitting portion 7 of the second body 6 by rubber having an insulating property, and a cup-shaped movable contact 10 is fixed to an upper surface of a central portion thereof.

In this embodiment, the movable contact 10 has a plurality of contact portions 11, 12, 13 projecting upward from the peripheral edge.

As shown in FIG. 1, on both sides 5 a and 5 b in the circumferential direction of the convex portion 5 of the first body 1, the mold can be opened in the left and right directions indicated by arrows X 1 and X 2 corresponding to the connector lock portions 3. The molding dies 1 and 15 are
When the molds 4 and 15 are opened, a draft that can be removed is formed.

For example, in the present embodiment, the molding dies 14, 15
The six convex portions 5 are formed at an equal angle of 60 degrees around the divided surfaces 16 and 17 of the above, and the circumferential side portions 5a and 5b of the convex portions 5 are formed at 60 degrees. A draft is formed as an inclined surface to be included.

As shown in FIG. 3, the fitting portion 4 of the first body 1 is internally fitted to the fitting portion 7 of the second body 6, and the fitting portions 4 and 7 of the diaphragm 9 The first and second bodies 1 and 6 are fixed while maintaining airtightness by compressing and sandwiching the outer peripheral portion and engaging the convex portion 5 of the first body 1 with the concave portion 8 of the second body 6. It is.

Thus, the first pressure action chamber 18 is formed by the first body 1 and the diaphragm 9, and the second pressure action chamber 19 is formed by the diaphragm 9 and the second body 6.

The first pressure action chamber 18 has a diaphragm 9
And the fixed contact 20 for the positive electrode and the fixed contact 21 for the negative electrode arranged side by side on the upper wall surface of the concave portion forming the first pressure action chamber 18 of the first body 1 are arranged so as to face each other. is there.

The movable contact 10 has one contact portion 11 corresponding to the fixed contact 20 for the positive electrode, and the other contact portion 12 of the movable contact 10 corresponds to the fixed contact 21 for the negative electrode.

The first body 1 has a fixed contact 20 for the positive electrode.
The extended positive electrode terminal 22 and the negative electrode terminal 23 extended from the negative fixed contact 21 are embedded.

When an external connector (not shown) is inserted into the receiving hole 2 of the first body 1, the positive connector 24 and the negative electrode 25 of the electric circuit are connected to the positive terminal 22 protruding from the bottom of the receiving hole 2 by the external connector. While being connected to the negative electrode terminal 23, the external connector is engaged with and fixed to the connector lock portion 3 (see FIG. 1) of the first body 1.

A switch spring 26 is housed in the center of the second body 6.

The switch spring 26 has an upper end in contact with a synthetic resin spring seat 27 fixed by caulking together with the movable contact 10 on the side surface of the diaphragm 9 on the side of the second pressure action chamber 19, and a lower end thereof in the second body 6. Abuts on a synthetic resin screw 28 screwed in the center of the screw.
The movable contact 10 and the diaphragm 9 are urged toward the fixed contact 20 for the positive electrode and the fixed contact 21 for the negative electrode by the spring force adjusted by the fastening amount of the fixed contact 8.

The first body 1 has a communication hole 31 for connecting the first pressure action chamber 18 to an annular atmospheric pressure side passage 30 formed by the first body 1 and a cover 29 externally fitted to the first body 1.
Is formed.

Outside the second body 6, a seal member 32 for maintaining airtightness when the second body 6 is attached to a vehicle body side member (not shown) is mounted.

When the central passage 33 of the second body 6 attached to the vehicle body side member is connected to a vacuum path (not shown) on the side where pressure is detected, the internal negative pressure value of the second pressure action chamber 19 is set. Is lower than the predetermined pressure value, the contact portions 11 and 12 of the movable contact 10 contact the fixed contact 20 for the positive electrode and the fixed contact 21 for the negative electrode due to the elasticity of the switch spring 26, and the pressure switch is turned on. While closing the electric circuit, when the internal negative pressure value of the second pressure action chamber 19 is higher than the predetermined pressure value, the action of the diaphragm 9 causes the contact portions 11 and 12 of the movable contact 10 to be moved by the switch spring 26. When the fixed contact for positive electrode 20 and the fixed contact for negative electrode 21 are further separated from each other against the force, the pressure switch is turned off to open the electric circuit.

According to the structure of the above embodiment, the first body 1 is in contact with the movable contact 10 attached to the diaphragm 9.
Since the fixed contact 20 for the positive electrode and the fixed contact 21 for the negative electrode which are separated from each other and the conduction on the side of the second body 6 from the diaphragm 9 is unnecessary, the control point for the conduction can be reduced as a matter of course. Since the first body 1 and the second body 6 are made of a synthetic resin, the moldability is good, the cost is advantageously obtained, and the weight can be reduced.

Further, the fitting portions 4 and 7 of the first body 1 and the second body 6 are fitted to each other, and the projection 5 of the first body 1 is connected to the second body 6.
Since the first and second bodies 1 and 6 can be assembled with one touch by sandwiching the outer peripheral portion of the diaphragm 9 by engaging with the concave portion 8 of this embodiment, the assemblability can be further improved.

Also, as shown in FIG. 1, on both sides 5a and 5b in the circumferential direction of the plurality of protrusions 5 of the first body 1, the left and right directions indicated by arrows X1 and X2 correspond to the connector lock portions 3. Since the molds 14 and 15 divided so as to be mold-openable have a draft that can be removed when the molds 14 and 15 are opened, the convex portion 5 is formed on the outer peripheral surface of the first body 1. Molds 14 and 15
Therefore, the molding of the first body 1 can be easily performed without any hindrance to the mold removal during the molding of the first body 1.

Further, the plurality of convex portions 5 of the first body 1 are radially equally arranged in the circumferential direction and provided.
The first and second bodies 1 and 6 can uniformly compress and clamp the entire outer peripheral portion of the diaphragm 9, so that the first and second bodies 1 and 6 can be clamped. The airtightness of the fitting portions 4 and 7 of the two bodies 1 and 6 can be improved.

In particular, since each of the projections 5 is formed to have the same area, the first and second projections 5 are engaged with the first and second projections 5 to engage with the depressions 8.
When the outer peripheral portion of the diaphragm 9 is compressed and sandwiched between the fitting portions 4 and 7 of the bodies 1 and 6, the reaction force due to the resilient elasticity from the diaphragm 9 is reduced by the engaging portion between each convex portion 5 and the concave portion 8. Thus, the airtightness of the fitting portions 4 and 7 of the first and second bodies 1 and 6 can be further improved.

The concave portion 8 of the second body 6 can be easily formed by a known slide core provided in a mold.

In the above embodiment, the first body 1 is provided with the six convex portions 5, but the number of the convex portions 5 is not limited.

[0044]

As described above, according to the present invention, the following effects can be obtained.

According to the first aspect, the first body is provided with two fixed contacts for the positive electrode and the negative electrode which come into contact with and separate from the movable contact attached to the diaphragm, so that conduction on the second body side from the diaphragm is unnecessary. Therefore, the number of control points for conduction is reduced, and therefore, the electrical conduction structure can be simplified, and the cost can be reduced by reducing the number of conduction portions.

Further, since the first body and the second body are made of synthetic resin, the moldability of the first and second bodies is good, the cost is advantageously obtained, and the weight can be reduced.

Further, by fitting the first body and the second body into each other and engaging the projections of the first body with the recesses of the second body, the first and second bodies are sandwiched by the outer peripheral portion of the diaphragm. Since the body can be assembled with one touch, the assemblability can be further improved.

Further, since a plurality of projections of the first body are formed with draft angles on both sides in the circumferential direction for punching from the molding die, the projections are formed radially on the outer peripheral surface of the first body. Even if it protrudes, there is no hindrance to the die removal during the molding.

The projections of the first body are radially equally spaced in the circumferential direction so as to engage with the recesses of the second body, so that the outer periphery of the diaphragm is formed by the first and second bodies. Since the entire circumference of the portion can be uniformly compressed and clamped, the airtightness of the fitting portion between the first and second bodies can be improved.

According to the second aspect, since the plurality of projections 5 are formed to have the same area, the projections and the recesses are engaged with each other to form the diaphragm at the fitting portion between the first and second bodies. When the outer peripheral portion is compressed and sandwiched, the reaction force due to the resilient elasticity from the diaphragm can be uniformly borne by the engaging portions between the respective convex portions and the concave portions,
The airtightness of the fitting portion between the first and second bodies can be further improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a fitting portion of a first body and a molding die according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing first and second bodies and a diaphragm of the embodiment.

FIG. 3 is an exemplary sectional view showing the pressure switch of the embodiment;

FIG. 4 is an exploded perspective view showing first and second bodies and a diaphragm conceived in a process leading to the present invention.

FIG. 5 is a sectional view showing a first body and a molding die shown in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st body 4 fitting part 5 convex part 6 2nd body 7 fitting part 8 concave part 9 diaphragm 10 movable contact 18 1st pressure action chamber 19 2nd pressure action chamber 20 fixed contact for positive electrodes 21 fixed contact for negative electrodes

Claims (2)

[Claims] A first body and a second body made of a synthetic resin material are coaxially fitted and mounted with an outer peripheral portion of the diaphragm interposed therebetween, and the first body is inserted into the first body and the second body by the diaphragm. A pressure action chamber and a second pressure action chamber,
A movable contact which is provided with two fixed contacts for a positive electrode and a negative electrode in a first body of a pressure action chamber and which comes into contact with or separates from the fixed contact on a diaphragm by a pressure difference between internal pressures of the first and second pressure action chambers. And a plurality of protrusions that engage with recesses provided in the fitting portion of the second body are radially equally arranged on the outer peripheral surface of the fitting portion of the first body in the radial direction. A pressure switch formed on both sides in the circumferential direction of the convex portion so as to be able to remove the mold when the mold is opened so that the mold can be opened in one direction. . 2. The pressure switch according to claim 1, wherein the plurality of projections have the same area.