JPH09282965A - Switch device provided with waterproof structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To securely prevent water by winding a tape around the surface of a switch case in contact with a waterproof cover so as to bond the cover to the case, and doubly molding the cover made of a predetermined synthetic resin with respect to the switch case and a terminal base. SOLUTION: A pair of projections 54, 55 are formed in a diameter reduced portion defined by a step part 53 near the rear end at the center outward of a metallic switch case 51 having a nearly cylindrical shape. The diameter reduced portion of the case 51, a terminal base 57, projections of metallic plates 58, 59 and part of each of lead wires 63, 64 are covered with a waterproof cover 75 made of a thermoplastic resin. An adhesive tape 74 is wound across the pair of projections 54, 55, so that the case 51 is welded to the cover 75. The tape 74 is wound around the portions of the lead wires 63, 64, covered with the cover 75. The cover 75 is made of a synthetic resin having substantially the same linear expansion coefficient as that of the terminal base 57, and further, is doubly molded with respect to the case 51 and the terminal base 57.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch device used, for example, in a hydraulic warning light of an automobile, and more particularly to a switch device having a waterproof structure.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional switch device. Reference numeral 1 is a cylindrical device body made of metal and having a small diameter portion 1a.
And a large-diameter portion 1b. A cylindrical bottomed insulator 2 is inserted into and fixed to the large-diameter portion 1b, and the plastic insulator 2 and the large-diameter portion 1b are used. A switch chamber 3 is formed, and a pressure detection chamber 4 is formed inside the small diameter portion 1a.

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

Reference numeral 7 is a plastic flexible and deformable sheet.
This seal film 7 has a peripheral edge portion which is a guide member 5.
And the guide member 5 and the packing 8 provided between the switch chamber 3 and the pressure detection chamber 4.
It is provided so as to airtightly separate the spaces.

Reference numeral 9 denotes a movable body disposed in the switch chamber 3. The movable body 9 is guided by the guide member 5 so as to be movable in the vertical direction in FIG. 3, and its head 9a is provided. The shaft portion 9b is provided so as to abut 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 movable body 9 is restricted by the flange portion 5a of the guide member 5 and the inner plate 6, and the movable body 9 has a shaft portion 9b having a reinforced plastic tip portion. And other portions are made of metal.

Reference numeral 10 denotes a bush held between an inner plate 6 and a step portion 2a formed on the inner side of the insulator 2, and a shaft portion of the moving body 9 is inserted into a through hole 10a formed at the center of the bush. 9b is penetrated.

Reference numeral 11 is a disc spring arranged on the inner plate 6, and the disc spring 11 has a shaft portion 9b penetrating the center hole portion 11a, and the center hole portion 11a and the shaft portion 9b are fitted to each other by the above fitting. The movement in the radial direction (the direction orthogonal to the shaft portion 9b) is restricted. Further, a predetermined play is formed between the outer peripheral end 11b 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. A movable plate 14 integrally includes a movable contact 15 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, when no pressure is applied to the pressure detection chamber 4, the disc spring 11 is in the return position shown by the solid line in FIG. 3, and 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 not in contact with the movable plate 14, and 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 accordance with the movement of the moving body 9, pressure acts on the periphery of the central hole portion 11a of the disc spring 11, and the disc spring 11 is deformed.

When the pressure applied to the pressure detection chamber 4 exceeds a predetermined value and the disc spring 11 is deformed to a position slightly above the predetermined neutral position, the disc spring 11 is moved to the inversion position shown by the chain double-dashed line in the figure. Toggle transforms. Due to this toggle deformation, the moving body 9 also moves to the position shown by the chain double-dashed line in the figure, whereby the movable plate 14 is pushed downward by the shaft portion 9b of the moving body 9, and the movable contact 15 separates from the fixed contact 12. The switch turns off.

As described above, the switch is turned off 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.

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 is toggle-deformed to the return position by the spring force of, so that the movable contact 15 comes into contact with the fixed contact 12 and the switch is turned on again.

[0015]

In the switch device described above, since the device body 1 is made of a metal material and the insulator 2 is made of a plastic material, a space between the device body 1 and the insulator 2 is formed. A gap is likely to occur in Further, since this switch device does not have a waterproof structure, water enters through the above-mentioned gap and infiltrates into the switch chamber 3, causing damage to the switch device.

[0016]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems of the switch device.
A switch made of a synthetic resin material fixed in the switch case such that a part of the switch case projects from one end side.
In addition to being equipped with a terminal base, a waterproof cover made of a synthetic resin material having the same or substantially the same linear expansion coefficient as the terminal base is provided, and the switch case and the terminal base are provided on one end side of the switch case. In a switch device having a waterproof structure in which the outer surface portion of the device is covered with the waterproof cover by contacting the switch case and the waterproof cover on the outer surface of the switch case which is in contact with the waterproof cover.
A switch device provided with a waterproof structure, characterized in that an adhesive tape for adhering to and is wound, and the waterproof cover is formed by double molding on the switch case and the terminal base. To propose.

[0017]

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 side view of the switch device 50.

From these drawings, 51 is a switch case, and this switch case 51 is a metallic one formed in a substantially cylindrical shape, in which a space 52 is formed, and on the outside, a center is formed. The reduced diameter portion is formed by the step portion 53 slightly closer to the rear end than the portion, and the two annular projections 5 are formed in the reduced diameter portion.
4, 55 are provided. Further, at the tip of the switch case 51, a screw portion 56 having an opening 56a for connecting with another device is formed.

In the space 52 of the switch case 51, a terminal base 57 made of a synthetic resin material is installed. The terminal base 57 is installed in the switch case 51 such that the rear end portion 57a of the terminal base 57a projects from the opening formed at the rear end of the switch case 51, and the switch case 51 is caulked and fixed. There is also this
Metal plates 58, 59 provided so as to protrude from the rear end portion 57a are fixed to the miner base 57.

The plates 58 and 59 described above are arranged in a groove 57b formed at an approximately central portion of the terminal base 57, the tip of which is bent into an L-shape, and one of the plates 58 is formed. A fixed contact 60 is fixed to the tip.

On the other side of the plate 59, an elastic spring 61, which is bent so that its tip is disposed in the groove 57b of the terminal base 57, is connected. A movable contact 62 facing the fixed contact 60 is fixed to the tip.

At the rear ends of the plates 58 and 59,
The lead wires 63 and 64 are fixed to each other by spot welding or soldering means, and the lead wires 63 and 64 are connected to a connecting tool 65 for connecting to an external device.

In the space 52 of the switch case 51, a bearing member 66, a support shaft member 67, and a diaphragm 68 formed of a flexible material such as rubber or synthetic resin material are sequentially installed from the terminal base 57 side. There is.

The bearing member 66 has an appropriate thickness, is provided with a small diameter hole 66a at the center, a concave portion 66b communicating with the small diameter hole 66a is formed at the front end side, and a rear end side is provided with a terminating end portion. It is joined to the minar base 57.

The supporting shaft member 67 is formed to be slightly thicker than the bearing member 66, and has a large diameter hole 67a formed at the center thereof and a concave portion 67b communicating with the large diameter hole 67a at the tip side thereof. The rear end side is joined to the bearing member 66.

The diaphragm 68 has an annular groove 51 whose outer peripheral surface is formed inside the tip portion 51b of the switch case 51.
The outer peripheral surface is joined to the support shaft member 67.
The switch case 5 is provided by the diaphragm 68 described above.
1, a pressurizing chamber 51d is formed on the lower side in the drawing, and the pressurizing chamber 51d communicates with the outside through an opening 56a of the screw portion 56, and an operation formed on the upper side of the pressurizing chamber 51d. The chamber is kept airtight by this diaphragm 68.

The bearing member 66, the support shaft member 67, and the diaphragm 68 described above are retained by a terminal base 57 fixed to the switch case 51.

A drive member 69 is provided in the space 52 of the switch case 51. The drive member 69 is the enlarged head 70.
And a drive section 72 having a diameter smaller than that of the expanded head 70 and a diameter smaller than that of the short shaft 71, and the expanded head 70 is brought into contact with the diaphragm 68 to form the short shaft 71.
Is inserted into the large diameter hole 67a of the support shaft member 67, and the drive portion 72 is inserted into the small diameter hole 66a of the bearing member 66.

This drive member 69, as shown in FIG.
Enlarged head 70 arranged in the concave portion 67b of the support shaft member 67.
Is not in contact with the support shaft member 67 in the normal state, and the tip of the drive portion 72 projects from the bearing member 66, and the tip surface is in contact with the elastic spring 61.

Further, the tip end of the short column shaft portion 71 is the bearing member 6.
6 in the concave portion 66b.

A circular disc spring 73 is provided in the concave portion 66b of the bearing member 66. In the disc spring 73, the drive portion 72 of the drive member 69 penetrates through the central hole 73 a and engages with the tip end surface of the short column shaft portion 71.

The disc spring 73 has a hollow central portion, and the outer peripheral edge portion 73b has a concave portion 6 of the bearing member 66.
It is formed such that it abuts on the bottom surface 66c of 6b and there is some play between the outer peripheral edge portion 73b and the inner wall of the concave portion 66b.

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.
Acrylic film composite material or the like is applied on both sides, and is joined to each of the switch case 51 and a waterproof cover 75 described later.

As shown in FIG. 2, 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 57, the plate 58, which closes the opening at the rear end of the switch case 51, A waterproof cover 75 in which the periphery including the protruding portions of 59 and the lead wires 63 and 64 is formed of a thermoplastic resin material.
Covered by.

The waterproof cover 75 is a terminal base 57.
And a switch case 51 and a terminal base 57 are 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 sudden temperature change occurs, the waterproof cover 75 made of synthetic resin and the metallic switch case 51 are formed.
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 is attached to an external device that supplies oil or compressed air with a screw portion 56, and operates by applying hydraulic pressure or air pressure from the external device to the pressurizing chamber 51d.

When the pressure is not applied to the pressurizing chamber 51d, the driving member 69 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 It is in the first state.

When pressure is applied to the pressurizing chamber 51d, this pressure is transmitted to the driving member 69 via the diaphragm 68, and the driving member 69 is pushed by the short column shaft portion 71 around the opening 73a of the disc spring 73. Drive to do.

When the driving force of the driving member 69 exceeds a predetermined elastic force of the disc spring 73, the disc spring 73 is instantly deformed from the return position shown in FIG. That is, the disc spring 73 is
The outer peripheral edge portion 73b is the bottom surface 6 of the concave portion 66b of the bearing member 66.
6c is abutted against and restrained from moving, the opening 7
The pressure applied to the periphery of 3a acts on the outer peripheral edge portion 73b to deform it. The deformation of the disc spring 73 is stopped when the periphery of the opening 73a abuts the bottom surface 66c of the concave portion 66b of the bearing member 66. Therefore, the disc spring 73 is deformed to the neutral position at the maximum.

Due to the above deformation of the disc spring 73, the drive member 69 instantaneously moves upward in FIG. 2, and this movement causes the drive portion 72 to push the elastic spring 61 so that the movable contact 62 becomes the fixed contact 60. Upon contact, the switch switches from the first state to the second state.

In the drive member 69 described above, the engaging surface 70a of the expanding portion 70 is the bottom surface 67c of the concave portion 67b of the support shaft member 67.
The movement is blocked by abutting against.

Next, when the pressure in the pressurizing chamber 51d drops to a predetermined pressure, the disc spring 73 is elastically deformed to the return position shown in FIG. 2, and this deformation causes the short column shaft portion 71 of the drive member 69 to move. The elastic force of the disc spring 73 is applied to the drive member 6
9 instantly moves to the normal position. As a result, the elastic spring 61 is released from the pushing force of the drive unit 72, the movable contact 62 is separated from the fixed contact 60, and the switch is switched from the second state to the first state.

[0046]

As described above, in the switch device according to the present invention, the adhesive tape for adhering the switch case and the waterproof cover is wound around the outer surface of the switch case which is in contact with the waterproof cover. Because of this, this adhesive tape ensures a waterproof seal between the waterproof cover and the switch case.

Unlike an adhesive or the like, this adhesive tape does not take a curing time, so that the production yield does not occur and the productivity is improved.

Further, since the waterproof cover is formed by double molding with a synthetic resin material made of a material having the same or substantially the same coefficient of linear expansion as the terminal base, the waterproof cover and the terminal base. The waterproofness is surely maintained between the cloth and the cloth without the adhesive force thereof being deteriorated due to the expansion and contraction of each other.

[Brief description of drawings]

FIG. 1 is a plan view of a switch device according to the present invention.

FIG. 2 is an enlarged vertical side view of the switch device.

FIG. 3 is a vertical sectional side 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 bearing member 67 support shaft member 68 diaphragm 69 drive member 73 disc spring 74 adhesive tape 75 waterproof cover

Claims (1)

[Claims] 1. A terminal base made of a synthetic resin material fixed to the inside of the switch case such that a part of the switch case is projected from one end side of the switch case.
A waterproof cover made of a synthetic resin material having the same or nearly the same linear expansion coefficient as the minal base is provided, and the outer surface of the device is brought into contact with the above-mentioned switch case and the terminal base at one end side of the switch case. In a switch device having a waterproof structure which is covered with the waterproof cover, the switch case is provided on the outer surface of the switch case which is in contact with the waterproof cover.
A waterproof structure characterized in that an adhesive tape for adhering the waterproof cover to the case is wrapped around, and the waterproof cover is formed by double molding on the switch case and the terminal base. Switch device equipped with.