JP2581265Y2 - Waterproof switch structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof structure of a switch, and more particularly to a structure of a shaft of a neutral switch and a back lamp switch for a vehicle.

[0002]

2. Description of the Related Art As shown in FIG. 2, a neutral switch for an automatic interlock for a vehicle and a switch for turning on a back lamp are known. In FIG. 2, a metal switch body 1 is shown.
The working chamber 17 is formed inside one side of 0, and the end is an opening. A step 18 is formed in the opening on the outer peripheral side, and is caulked. On the other side of the switch body 10 made of metal, a screw portion 11 is formed, and a hole portion through which the shaft 20 is inserted is provided at the center.

The shaft 20 is composed of a large diameter portion and a small diameter portion having substantially the same length, the end of the large diameter portion is formed in a spherical shape, and a groove 21 is formed near the boundary with the small diameter portion. After being assembled into a sub-assembly, it is assembled into the body 10. A contact spring 22 composed of a coil spring and a disc-shaped insulator 2 are provided on the small diameter side of the shaft 20.
3. A contact plate 41 having movable contacts 39 and 40 above and below, and a disk-shaped insulator 24 are inserted in this order, and these are prevented from coming off by an E-ring 29 and fixed.

A rubber packing 15 having a substantially S-shaped cross section is inserted and fixed in the groove 21 provided in the shaft 20 so that the periphery thereof is fixed and a sufficient deflection is obtained in the center. As shown in FIG. 3, a hole 16 having a diameter smaller than the diameter of the groove 21 is provided in the center of the rubber packing 15, and a shaft is inserted into the hole 16 by utilizing the elasticity of rubber at the time of insertion. The groove 21 is tightened by pushing the large-diameter portion 20 to expand it and dropping it into the groove 21. The parts attached around the shaft described above are assembled as a sub-assembly so far.

Next, the configuration of the terminal base 12 will be described. The terminal base 12 is made of a resin having a cylindrical shape with a substantially H-shaped cross section, and has a recess 13 formed in the center on the side of the working chamber 17, and a return spring 38 formed of a coil spring is inserted into the recess 13. Terminals 30 and 31 having knurled portions 34 and 35 at the center at the target position with the recess 13 as a center are erected by insert molding. Fixed contacts 32, 33 are provided at one end of the terminals 30, 31, and cords 36, 33 are provided at the other end.
36 can be fixed by means such as spot welding or soldering. The cord side of the terminal base 12 is potted 43 with an adhesive or the like so that measures such as humidity, vibration, and tension can be taken.

At the end of the terminal base 12 on the working chamber side, terminals 25 and 26 having fixed contacts 27 and 28 are provided at positions facing the fixed contacts 32 and 33, respectively. The terminals 25 and 26 are substantially L-shaped, and one piece is inserted into a hole (not shown) provided in the terminal base 12 and fixed, and the ends are projected from the opposite side to spot the cords 42 and 42. It can be fixed by means such as welding or soldering.

[0007] The assembly of this switch is based on the terminal base 1
The movable contacts 39 and 40 incorporated in the sub-assembled shaft 20 are arranged so as to face the terminals 30 and 31 integrated with the terminal 2, and the terminals 25 and 26 are inserted into the terminal base 12. After that, the spacer 14 is inserted from the large diameter portion of the shaft 20, and the terminals 25,
26 and the rubber packing 15. In this state, the terminal base 12 is inserted into the body 10 and caulked, and the terminal base 12 is fixed so as not to come off from the body 10.

Next, the operation will be described. When no external force is applied to the tip of the shaft 20, the amount of protrusion of the shaft 20 is maximum, and at this time, the fixed contacts 27 and 28 come into contact with the movable contacts 39 and 40 urged by the return spring 38, and the terminals 25 and 26 Is short-circuited.
Next, when an external force greater than the urging force of the return spring 38 is applied to the shaft 20, the shaft 20 moves rightward in FIG. Then, the movable contacts 39 and 40 are separated from the fixed contacts 27 and 28, and the terminal 25 and the terminal 26 become non-conductive.

When the shaft 20 further moves rightward, the movable contacts 39 and 40 come into contact with the fixed contacts 32 and 33 to short-circuit the terminals 30 and 31. At this time, the force by which the movable contacts 39 and 40 press the fixed contacts 32 and 33 is due to the urging force of the contact spring 22. The rubber packing 15 is provided between the shaft 20 and the hole 19 to prevent dust, water, oil, or the like from entering the inside of the switch. As described above, the hole 16 is formed with a step 21 having a larger diameter than the hole 21.
Is tightened. The periphery of the rubber packing 15 is tightly fixed by being sandwiched between the spacer 14 and the body 10, and the center thereof moves integrally with the shaft 20. For this reason, when the shaft 20 is pushed in, the above-mentioned cross-sectional shape is substantially S
The letter-shaped part is in an extended state.

[0010]

However, in the structure in which the hole 16 of the rubber packing 15 is pushed into the large diameter portion of the shaft 20 and the groove 21 is tightened by using the elasticity of the rubber, the temperature difference between the inside and the outside of the switch is reduced. A pressure difference between the inside and the outside of the switch due to a change in volume inside the switch due to movement of the rubber packing 15 or the center of the rubber packing 15 may cause dust, water or oil to be sucked into the inside of the switch. For this reason, in the conventional switch, there have been problems such as the fact that these adhere to the contacts inside the switch and cause insulation failure.

[0011]

According to the present invention, there is provided a contact plate having a movable contact, a shaft having the contact plate slidably fitted to one end thereof, and a rubber packing integrally formed at the center of the shaft. A terminal having a fixed contact, a terminal base provided with the terminal, a screw portion on one side, an operating chamber formed on the other side, and a sliding hole formed in the screw portion, the other end of the shaft being inserted into the sliding hole. A body in which the terminal base is arranged in a state where the movable contact and the fixed contact face each other in the working chamber and the outer peripheral edge of the rubber packing is in close contact with the inner surface of the working chamber. The shaft is provided with a flange, and an annular groove is provided on an outer peripheral surface of the flange.

[0012]

The present invention is constructed as described above,
When the adhesive is applied to the annular groove provided on the outer peripheral surface of the flange of the shaft, the adhesive can remain in the annular groove. For this reason, at the time of insert molding, the space between the shaft and the rubber packing is brought into close contact with each other and does not peel off. Therefore, even if a pressure difference occurs between the inside and the outside of the switch, dust, water, oil, and the like do not enter the inside of the switch, so that the outside of the switch is completely shielded.

[0013]

Next, an embodiment of the present invention will be described with reference to FIG. In the description, the same parts as those in the related art will not be described. The shaft 50 includes a large-diameter portion 51 having one end formed in a spherical shape, two flanges 53 and 54 having a groove 52 at the center, and a small-diameter portion 55 provided at the other end. The outer diameter of the first flange 53 provided on the large-diameter portion 51 side is slightly larger than the outer diameter of the large-diameter portion 51, and is located on the small-diameter portion 55 side with the groove portion 52 having substantially the same diameter as the small-diameter portion 55 interposed therebetween. The provided second flange 54 has a large diameter portion 51.
And are formed to have substantially the same diameter. The widths of the first flange 53, the groove 52, and the second flange 54 are substantially equal. V-shaped grooves 56 and 57, which are annular grooves having a V-shaped cross section, are formed on the outer peripheral surface of the first flange 53 and the second flange 54 parallel to the axis.

The shaft 50 constructed as described above
An adhesive (not shown) is applied to the existing V-shaped grooves 56 and 57 and the groove portion 52, and then assembled into a mold to form a rubber packing 6.
0 is integrally molded. In this way, the adhesive flows along the two V-shaped grooves 56 and 57 and the groove 52. At this time, the adhesive adhered to the V-shaped grooves 56, 57 remains in the V-shaped grooves 56, 57 without being drawn to the groove 52,
An appropriate amount of adhesive can be attached to both the V-shaped grooves 56 and 57 and the groove 52. In addition, since the V-shaped grooves 56 and 57 increase the surface area, the rubber packing 60 can be firmly formed on the shaft 50. Also, the first flange 5
3 and the small-diameter portion 55 of the second flange 54
The side surface is abutted when assembled into the mold and acts as a positioning member for the shaft 50.

When the insert molded product is used for a switch, the shaft 50 and the rubber packing 6 can be used even if the pressure changes due to the temperature difference between the inside and the outside of the switch and the volume change due to the movement of the center of the rubber packing 60.
Since it is sealed between 0 and 0, dust, water and oil do not enter the inside of the switch from here. Further, in this embodiment, the cross-sectional shape of the groove formed in the flanges 53 and 54 is V-shaped, but the same effect can be obtained even if the cross-sectional shape is trapezoidal, rectangular, square, semicircular, or the like.

[0016]

According to the present invention, since the rubber packing is firmly formed on the shaft, the inside of the switch and the outside of the switch are completely shielded.
It is possible to prevent dust, water, oil, and the like from entering the inside of the switch, and to prevent the occurrence of a defect such as a switch conduction failure or an insulation failure.

[Brief description of the drawings]

FIG. 1 is a front view of a main part of an embodiment of the present invention,

FIG. 2 is a longitudinal sectional view of a conventional switch device;

FIG. 3 is a perspective view showing an assembled state of a rubber packing and a shaft of a conventional switch device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Body, 12 ... Terminal base, 27, 28, 32, 33 ... Fixed contact, 39, 40 ... Movable contact, 41 ... Contact plate, 50 ... Shaft, 53, 54 ... Flange, 56, 57 ... V-shaped groove .

Claims (1)

(57) [Scope of request for utility model registration] A contact plate having a movable contact;
A shaft having the contact plate slidably fitted to one end thereof, a rubber packing integrally formed at the center of the shaft, a terminal having fixed contacts, a terminal base having the terminal, and A state in which a working section is formed in the screw section and the other side, and the other end of the shaft is inserted into a sliding hole formed in the screw section, and the movable contact and the fixed contact face each other in the working chamber. A body in which the terminal base is disposed and the outer peripheral edge of the rubber packing is closely attached to the inner surface of the working chamber, wherein the shaft is provided with a flange and an annular groove is provided on the outer peripheral surface of the flange. Features a waterproof switch structure.