JPH09282990A - Pressure switch device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure switch device having the stabilized switch operation and excellent durability. SOLUTION: This pressure switch device is provided with a movable contact 62, which contacts with a fixed contact 60 with the operation of a driving member 70 to be moved forward by the hydraulic pressure or pneumatic pressure, and a plate spring 73 having a curved cross section, which is deformed by the forward movement of the driving member 70 so as to store the spring force and which gives the reset force to the driving member 70. In this pressure switch device, when the plate spring 73 is deformed into a flat shape by the forward movement of the driving member 70, an enlarged head part 70a of the driving member 70 abuts on a bottom part of a recessed part 67b formed in a second bearing member 67.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure switch device, for example, a pressure switch device used for a hydraulic warning light of an automobile.

[0002]

2. Description of the Related Art FIG. 4 shows a conventional pressure switch device. Reference numeral 1 is a cylindrical metal device body having a small diameter portion 1a and a large diameter portion 1b, and a large diameter portion 1b having a cylindrical shape. A bottomed insulator 2 formed in a ring shape is inserted and fixed, and a switch chamber 3 is formed by the plastic insulator 2 and the large diameter portion 1b described above, and the pressure detection chamber 4 is formed in the small diameter portion 1a. Has become.

Reference numeral 5 is a short cylindrical guide member having a flange 5a, and 6 is an annular inner plate made of metal, which are arranged in a stepwise manner and housed in the switch chamber 3.

Reference numeral 7 is a plastic flexible and deformable sheet.
This is a seal film, the peripheral portion of which is sandwiched between the guide member 5 and the packing 8 provided between the guide member 5 and the apparatus main body 1, and the seal film 7 allows the switch chamber 3 and the pressure detection chamber to be held. The four are airtightly separated.

Reference numeral 9 denotes a moving body disposed in the switch chamber 3. The moving body 9 is guided by the guide member 5 so as to be movable in the vertical direction in FIG. 4, and its head 9a is provided. The shaft 9b is provided so as to contact the seal film 7, and a shaft portion 9b is formed so as to project from the center of the lower portion. The vertical movement of the moving body 9 is restricted by the flange portion 5a of the guide member 5 and the inner plate 6.

Reference numeral 10 denotes a bush held by a step portion 2a formed on the inner side of the insulator 2 and an inner plate 6, and a shaft portion 9b of the moving body 9 is provided in a central hole 10a of the bush.
Is axially inserted.

Reference numeral 11 denotes a disc spring disposed on the inner plate 6, and the disc spring 11 has the shaft portion 9b inserted in a central hole thereof so that the central hole and the shaft portion 9b are fitted to each other. The movement in the radial direction (the direction orthogonal to the shaft portion 9b) is restricted by. A predetermined play is provided between the outer peripheral end 11b of the disc spring 11 and the inner wall of the switch chamber 3.

A fixed contact 12 is provided on the lower surface of the bush 10. A terminal 13 integrally formed with the fixed contact 12 penetrates the insulator 2 and projects to the outside. Reference numeral 14 denotes a movable plate integrally having a movable contact 15, which is attached so as to be pushed by the tip of the shaft of the moving body 9 and is arranged so that the movable contact 15 faces the fixed contact 12.

Reference numeral 16 is a coil spring that constantly urges the movable plate 14 upward, and the movable contact 15 is pressed against the fixed contact 12 by the urging force. The spring force of the coil spring 16 is set to be larger than the spring force of the disc spring 11.

In the pressure switch device described above, the disc spring 11 is in the return position shown by the solid line in FIG. 4 when no pressure such as hydraulic pressure or pneumatic pressure is applied to the pressure detection chamber 4.
The moving body 9 is also in the position shown by the solid line. At the solid line position of the moving body 9, the shaft portion 9b of the moving body 9 is separated from the movable plate 14,
Therefore, the movable contact 15 is pressed against the fixed contact 12 by the spring force of the coil spring 16, and the switch is in the ON state.

When pressure is applied to the pressure detection chamber 4, the pressure is transmitted to the moving body 9 through the seal film 7, and the moving body 9 moves downward in FIG. In response to the movement of the moving body 9, pressure acts on the periphery of the central hole of the disc spring 11 to deform the disc spring 11.

When the applied pressure to the pressure detection chamber 4 exceeds a predetermined value and the disc spring 11 is deformed to a position slightly above a predetermined neutral position where it is flat, the disc spring 11 is turned to the reverse position shown by the two-dot chain line in the figure. Deform. By this reversal deformation, the moving body 9
Also moves to the position shown by the chain double-dashed line in the figure, and the movable plate 14 is pushed downward by the shaft portion 9b of the moving body 9, the movable contact 15 separates from the fixed contact 12, and the switch is turned off.

As described above, when the pressure applied to the pressure detection chamber 4 exceeds the total spring force of the disc spring 11 and the coil spring 16, the switch is turned off.

On the other hand, when the pressure applied to the pressure detection chamber 4 decreases and the resultant force of this pressure and the spring force of the disc spring 11 becomes less than the spring force of the coil spring 16, the coil spring 16
The disc spring 11 returns and deforms due to the spring force, and the movable contact 15 comes into contact with the fixed contact 12 to turn the switch on again.

[0015]

In the pressure switch device described above, the disc spring 11 is deformed from the return position to the reverse position when the switch is switched from ON to OFF, and when the switch is switched from OFF to ON. Is deformed from the reverse position to the return position. That is,
The disc spring 11 deforms each time the switch is turned on and off.

However, when the disc spring 11 is reversely deformed, a pressure exceeding the spring force of the disc spring 11 is applied to the periphery of the central hole, so that a high load is applied to the disc spring 11 each time the disc spring 11 is reversely deformed. The disk spring 11 is cracked or the disk spring 11 is cracked due to frequent ON / OFF operations, which causes problems in the stability of the switch operation and the durability of the switch device.

In view of the above-mentioned situation, the present invention provides a pressure switch device of this type which can enhance the durability of the disc spring and ensure the stability of the switch operation even in frequent ON and OFF operations. With the goal.

[0018]

DISCLOSURE OF THE INVENTION The present invention, however, includes a drive member for advancing and moving in a switch case by a pressure such as hydraulic pressure or air pressure, and a switch constituent portion which operates in conjunction with the advancing movement of the drive member. And a disc spring having a curved cross section that is deformed in a plane by the drive member and applies a restoring force to the drive member.

And, according to the present invention, the stopper member which the drive member abuts after the disk spring is deformed by pressure
And the disc spring is prevented from being applied with a pressure higher than a predetermined value.

The pressure switch device configured as described above is
The switch member moves from the first state to the second state as the drive member moves forward due to the pressure. Further, as the drive member advances and moves, the disc spring is deformed into a flat shape, and this state is maintained while a predetermined pressure or more is applied. At this time, even if a large pressure is applied, since the drive member is in contact with the stopper, the disc spring is not applied with a pressure higher than a predetermined value.

If the pressure decreases and the pressure disappears,
The drive member is returned by the spring force of the disc spring, the switch mechanism portion changes from the second state to the first state, and the disc spring returns to the normal cross-section curved state.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. 1 is a plan view of the switch device 50, and FIG. 2 is a vertical sectional view of the switch device 50.

From these drawings, 51 is a switch case, and this switch case 51 is made of a metal having a bottomed container, and the outer side thereof is a little closer to the rear end than the central part. A reduced diameter portion is formed by the portion 53, and two annular projections 54 and 55 are provided on the reduced diameter portion. Further, a screw portion 56 having a through hole 56a for connecting with other equipment is formed on the tip side of the switch case 51.

The switch case 51 is internally provided with a terminal base 57 made of a synthetic resin material. This tar
The miner base 57 is installed in the switch case 51 such that the rear end of the miner base 57 projects from the opening formed at the rear end of the switch case 51, and is caulked and fixed to the switch case 51. Further, a metallic plate 58 provided so as to protrude from the terminal base 57,
59 is fixed.

The plates 58 and 59 described above are arranged on the inner bottom surface of the concave groove 57a formed in the terminal base 57 on the tip side bent into an L shape, and the tip of one plate 58 is formed. A fixed contact 60 is fixed to the portion.

A spring plate 61, which is formed by bending one side part so as to be disposed in the concave groove 57a of the terminal base 57, is connected to the side part of the other plate 59. 6
A movable contact 62 facing the fixed contact 60 at the tip of
Is stuck. The spring plate 61 is a plate 59.
Is electrically connected to Also, the plates 58, 59
Lead wires 63 and 64 are fixed to the rear end portion by spot welding or soldering means.

On the other hand, in the switch case 51, a first bearing member 66, a second bearing member 67, and a diaphragm 68 are sequentially installed from the side closer to the terminal base 57.

The first bearing member 66 has a small diameter hole 6 at the center thereof.
6a is a concave portion 66b which communicates with the small diameter hole 66a on one surface side.
Are formed respectively, and the other surface side is joined to the terminal base 57.

The second bearing member 67 has a large-diameter hole 67a in the center thereof and a concave portion 6 communicating with the large-diameter hole 67a on one surface side.
7b are formed respectively, and the other surface side is joined to the first bearing member 66.

The diaphragm 68 is made of a flexible material such as rubber or synthetic resin material, and its peripheral portion is thickly formed. One surface of the outer periphery is formed into an annular groove 51a formed on the inner bottom surface of the switch case 51. The second bearing member 67 is fitted and joined to the other surface of the outer circumference.

A pressure chamber 51b is formed in the lower side of the switch case 51 by the diaphragm 68 in the figure, and the pressure chamber 51b communicates with the outside through a through hole 56a of the screw portion 56 and is also applied. The working chamber formed on the upper side of the pressure chamber 51b is airtightly maintained by the diaphragm 68.

The above-mentioned first bearing member 66, second bearing member 67, and diaphragm 68 are retained by a terminal base 57 fixed to the switch case 51.

A drive member 70 is provided in the switch case 51. The drive member 70 includes an expanded head 70a, a short column shaft portion 70b formed to have a diameter slightly smaller than that of the expanded head portion 70a, and a drive portion 70c having a diameter smaller than that of the short pillar shaft portion 70b. In contact with each other, the short column shaft portion 70b is inserted into the large diameter hole 67a of the second bearing member 67, and the drive portion 70c is inserted into the small diameter hole 66a of the first bearing member 66.
Has been inserted into.

The drive member 70, as shown in FIG.
The expanded head 70a is normally in non-contact with the second bearing member 67, the tip of the drive unit 70c projects from the first bearing member 66, and the tip surface is in contact with the spring plate 61,
Further, the tip step portion of the short column shaft portion 70b projects into the concave portion 66b of the first bearing member 66.

A circular disc spring 73 is provided in the concave portion 66b of the first bearing member 66. In the disc spring 73, the drive portion 70c of the drive member 70 penetrates the central hole of the disc spring 73 and engages with the tip step portion of the short column shaft portion 70b.

The disc spring 73 has a curved cross-sectional shape with a depressed central portion, and the outer peripheral edge portion abuts the bottom surface of the concave portion 66b of the first bearing member 66, so that the outer peripheral edge portion and the concave portion are formed. Part 6
It is formed so that there is some play with the inner wall of 6b.

On the other hand, an adhesive tape 74 is wound between the two annular projections 54 and 55 of the switch case 51.
The adhesive tape 74 is, for example, GHB excellent in heat resistance and cold resistance.
A double-sided adhesive tape coated with acrylic foam bonding material on both sides, which is a switch case 51 and a waterproof cover 75 described later.
It is designed to be joined to each.

As shown in FIG. 1, the above-mentioned adhesive tape 74 is also wound around a part of the lead wires 63 and 64, that is, a part covered with a waterproof cover 75 described later.

On the outer peripheral side of the switch case 51, the reduced diameter portion provided with the annular projections 54 and 55 and the terminal base 5 for closing the opening at the rear end of the switch case 51.
7, protrusions of plates 58 and 59, lead wires 63 and 64
The periphery including a part of is covered with a waterproof cover 75 made of a thermoplastic resin material.

The waterproof cover 75 is made of a synthetic resin material having the same or substantially the same coefficient of linear expansion as the terminal base 57, and the switch case 51 and the terminal base 5 are provided.
7 is formed by double molding. As a result, the resin material of the waterproof cover 75 is brought into close contact with the annular projections 54 and 55 of the switch case 51, the contact surfaces between them increase, and the creeping distance to the inside of the device 50 increases.

The waterproof cover 75 and the terminal base 57 are the terminal bases when the waterproof cover 75 is double-molded.
The surface of the cloth 57 is melted by the heat of fusion of the waterproof cover 75, and the synthetic resin materials are mixed with each other and sufficiently adhere to each other.

When a rapid temperature change occurs, the synthetic resin waterproof cover 75 and the metallic switch case 51 are used.
Although a slight gap may occur between the switch case 51 and the terminal base 57, an adhesive tape 74 that adheres to both the switch case 51 and the terminal base 57 prevents water from entering through the gap.

Next, the operation of the above switch device 50 will be described. The switch device 50 operates by connecting the screw portion 56 to an external device that supplies oil or compressed air and applying hydraulic pressure or air pressure from the external device to the pressurizing chamber 51b.

When no pressure is applied to the pressurizing chamber 51b, the driving member 70 is in the normal position as shown in FIG. 2, the movable contact 62 and the fixed contact 60 are not in contact with each other, and the switch is in the OFF state. It is in.

When pressure is applied to the pressurizing chamber 51b, this pressure is transmitted to the driving member 70 via the diaphragm 68,
The drive member 70 moves forward and the periphery of the central hole of the disc spring 73 is pushed by the short column shaft portion 70b of the drive member 70.

The driving force applied to the driving member 70 is the disc spring 73.
2 is exceeded, the disc spring 73 deforms from the normal position shown in FIG. That is, since the outer peripheral edge portion of the disc spring 73 abuts on the bottom surface of the concave portion 66b of the first bearing member 66 and its vertical movement is restricted, the disc spring 73 is pushed by the driving member 70 around the central hole. It deforms into a flat surface due to power. That is, as shown in FIG. 3, the disc spring 73 is deformed into a flat surface to store the spring force.

Due to the above deformation of the disc spring 73, the driving member 70 instantaneously moves upward in FIG. 2, and this movement causes the driving portion 70c to push the spring plate 61 to move the movable contact 62 to the fixed contact 60. And switch the switch from OFF to ON. At this time, the expanded head portion 70a of the driving member 70 contacts the bottom portion of the concave portion 67b formed on the second bearing member 67, and prevents the driving member 70 from further moving. In other words, even if an excessive pressure is applied, since the expanded head portion 70a of the drive member 70 is in contact with the bottom portion of the concave portion 67b, the disc spring is not deformed more than necessary. In this way, the second bearing member 70 functions as a stopper.

When the pressure in the pressurizing chamber 51b drops to a predetermined pressure, the disc spring 73 returns to the position shown in FIG. 2 by its spring force, and this return operation causes the drive member 70 to instantaneously move to the normal position. As a result, the movable contact 62 is separated from the fixed contact 60 and the switch is switched from ON to OFF.

[0049]

As described above, in the pressure switch device of the present invention, the disc spring is deformed into a flat shape by the advancing movement of the driving member, but even if an excessive pressure is applied, the driving member contacts the stopper. , The disc spring does not receive more than the specified pressure. From this, it is possible to improve the durability of the disc spring, and as a result, a pressure switch having stable switch operation and excellent durability is obtained.

[Brief description of drawings]

FIG. 1 is a plan view of a pressure switch device shown as an embodiment of the present invention.

FIG. 2 is a vertical sectional view of the switch device.

FIG. 3 is a partially enlarged cross-sectional view of the pressure switch device showing a switch operation.

FIG. 4 is a vertical sectional view of a switch device shown as a conventional example.

[Explanation of symbols]

 50 switch device 51 switch case 57 terminal base 60 fixed contact 62 movable contact 66 first bearing member 67 second bearing member 68 diaphragm 70 drive member 73 disc spring

Claims (1)

[Claims] 1. A switch member provided with a drive member for advancing and moving in a switch case by a pressure such as hydraulic pressure or air pressure, and a switch component operating in conjunction with the advancing and moving movement of the drive member, and deformed into a plane by the drive member. And a disc spring having a curved cross section for giving a restoring force to the drive member, the drive member includes a stopper that abuts after the disc spring is deformed by pressure, and the disc spring is A pressure switch device, characterized in that pressure above a prescribed value is prevented from being applied.