JPH11297147A - Contact structure of movable contact plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To always obtain a good contact surface by cleaning the surface of a fixed contact with a contact of a movable contact plate. SOLUTION: A base end of a movable contact plate 1 is fixed, a distal end 2 of the movable contact plate faces a fixed contact 3, and a movable contact plate 1 is fixed.
In the contact structure of the movable contact plate in which the tip 2 is pressed to contact the fixed contact 3, a curved contact 4 is formed at the tip 2 of the movable contact plate 1, and when the movable contact plate 1 is pressed, The contact 4 slides on the surface 3c of the fixed contact 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact structure of a movable contact plate capable of cleaning the surface of a fixed contact with the contact of the movable contact plate.

[0002]

2. Description of the Related Art FIGS. 4 and 5 show a conventional automobile switch to which a movable contact plate is applied.

As shown in FIG. 4, a movable contact plate 15 is formed in a substantially L shape using a conductive metal as a material, and a base end portion thereof is fixed to a housing 16 made of an insulating resin. The distal end (free end) of the movable contact plate 15 is bent downward and faces the fixed contact 18 of the circuit board 17 on the housing side. The fixed contact 18 continues to the lead terminal 19. Movable contact plate 15
The intermediate portion is pressed by the protrusion 21 of the operation lever 20 and bends downward, and the contact 22 at the distal end portion elastically contacts the fixed contact 18.

As shown in FIG. 5, an operating lever 20 is supported on a shaft 23 and is rotatable toward the driver as shown by an arrow A. In a free state, the operating lever 20 is urged in the axial direction by a coil spring 24 to protrude. The part 21 is lightly in contact with the movable contact plate 15. By operating the operation lever 20 in the direction of arrow A, the projection 21 rotates in the opposite direction with the shaft 23 as a fulcrum, and the movable contact plate 1
5 is pressed toward the circuit board 17.

The window washer fluid is spouted or the passing light is turned on by operating the lever in the direction of arrow A. If the operation lever 20 is rotated in a direction orthogonal to the arrow A, the wiper is turned on or off or the turning light is blinked.

FIG. 6 shows a state before the operation lever 20 (FIG. 5) is operated.
5 is lightly in contact with the middle part in the longitudinal direction. Movable contact plate 15
Are located opposite the fixed contact 18.

FIG. 7 shows a state in which the operating lever 20 (FIG. 5) is pulled in the direction of arrow A, the projection 21 presses the movable contact plate 15, and the contact 22 of the movable contact plate 15 contacts the fixed contact 18. It is shown. The contact 22 of the movable contact plate 15 is in contact with the fixed contact 18 at the edge 22a.

FIG. 8 shows a state in which the protrusion 21 is overstroke, the movable contact plate 15 bends downward with the edge 22a at the tip as a fulcrum, and the tip 25 is bent at a slightly acute angle. Overstroke occurs relatively frequently due to strong lever operation, assembling dimensional error, and the like, and sometimes overstroke intentionally to ensure contact pressure in design.

[0009]

However, in the above-mentioned conventional structure, the contact 22 of the movable contact plate 15 comes into contact with the same position during the overstroke (FIG. 8). The fixed contact 18 is easily damaged,
There was a concern that this could result in poor contact. In addition, the contact 22 of the movable contact plate 15 bites into the fixed contact 18 at the time of the overstroke, and often contacts the same place (at one point) as at the time of the normal stroke (FIG. 7). There is a concern that an insulating film of carbide or the like is likely to be formed on the surface of the fixed contact 18 and that when the contact 22 of the movable contact plate 15 contacts a portion other than the same portion during an overstroke, poor conduction may occur. Was.

[0010] In view of the above, the present invention does not cause a coating such as a carbide on the surface of the fixed contact with time, or does not damage the fixed contact due to contact with the movable contact plate. It is an object of the present invention to provide a contact structure of a movable contact plate that can exhibit excellent electrical contact.

[0011]

In order to achieve the above object, the present invention provides a movable contact plate having a fixed base end, a distal end of the movable contact plate facing a fixed contact, and a movable contact plate. In the contact structure of the movable contact plate in which the tip is pressed to contact the fixed contact, a curved contact is formed at the tip of the movable contact plate, and the contact is formed when the movable contact plate is pressed. Slides on the surface of the fixed contact.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an embodiment of a contact structure of a movable contact plate according to the present invention.

In this embodiment, the tip 2 of the movable contact plate 1 made of a conductive metal has a substantially V-shaped or U-shaped curve toward the fixed contact 3. A contact (movable contact) 4 is located at the center of the curved portion (2). The contact 4 has a smoothly curved round contact surface.

A front inclined portion 6 is formed obliquely upward from the contact 4 to the free end 5 of the movable contact plate 1, and a rear inclined portion 7 is formed obliquely upward from the contact 4 to the straight portion 8 of the movable contact plate 1. Have been. In the free state of the movable contact plate 1, the front inclined portion 6 protrudes slightly higher than the straight portion 8. A base end 8a of the straight portion 8 is fixed to a vertical wall 10 of a housing 9 made of insulating resin. The movable contact plate 1 has elasticity in the thickness direction.

The fixed contacts 3 are arranged on a horizontal circuit board portion 11 of the housing 9. As shown in FIG.
In a state where the movable contact plate 1 is not pressed (for example, a projection or a push pin that moves up and down by operating the operation lever) (the free state of the movable contact plate 1), the contact 4 of the movable contact plate 1 is the width of the fixed contact 3. It is located facing the center in the direction (the center of the width L). The pressing portion 12 is in contact with the straight portion 8 at substantially the center in the length direction of the movable contact plate 1.

FIG. 2 shows a state in which the pressing portion 12 presses the movable contact plate 1 downward as shown by the arrow B, and the contact 4 of the movable contact plate 1 starts to contact the fixed contact 3.

The contact 4 of the movable contact plate 1 is in contact with the fixed contact 3 on the rearward side 3a in the width direction. Since the contact 4 of the movable contact plate 1 is smoothly curved as described above, it does not hit the fixed contact 3 at the edge as in the conventional case.

FIG. 3 shows a state in which the pressing portion 12 overstrokes in the direction of arrow B to strongly press the movable contact plate 1 downward.

The movable contact plate 1 is slightly curved downward, and the contact 4 of the movable contact plate 1 slides smoothly on the surface 3c of the fixed contact 3. The contact 4 of the movable contact plate 1 moves from the rear 3a in the width direction of the fixed contact 3 to the front 3b in the width direction as shown by the arrow C. By the sliding action of the contact 4, the surface 3c of the fixed contact 3 is cleaned.

As a result, the insulating film such as carbide, which is a weak point of the general opposed contact, is removed from the fixed contact 3 and the movable contact 4, and the surfaces of the fixed contact 3 and the movable contact 4 are always kept clean without the adhesion of the film. Dripping. In addition, as the contact 4 moves, excessive stress (residual bending stress) of the movable contact plate 1 is removed. Thereby, the elasticity of the movable contact plate 1 does not weaken over time, and a good contact pressure is always exerted. Further, since the contact 4 of the movable contact plate 1 does not contact the fixed contact 3 at the edge unlike the conventional case, the fixed contact 3 is prevented from being damaged, and a good contact surface is secured.

The present embodiment is not limited to the automotive switch described in the prior art, but can be applied to any contact structure. Tip 2 including contact 4 of movable contact plate 1
The shape of is not limited to a substantially V-shaped or U-shaped as in this example,
Anything may be used as long as the contact surface is curved, such as a semicircle or a circle.

[0022]

As described above, according to the present invention, as the movable contact plate is pressed in the direction of the fixed contact, the curved contact of the movable contact plate smoothly slides on the surface of the fixed contact. Thus, the surface of the fixed contact is cleaned, and a film such as carbide is removed from the surface of the fixed contact, so that a good contact surface is always obtained and the fixed contact is prevented from being damaged.
As a result, the reliability of the electrical connection is improved.

[Brief description of the drawings]

FIG. 1 is a side view showing one embodiment of a contact structure of a movable contact plate according to the present invention.

FIG. 2 is a side view showing a state where a movable contact plate is initially pressed and comes into contact with a fixed contact.

FIG. 3 is a side view showing a state in which the movable contact plate is pressed slightly over stroke.

FIG. 4 is a longitudinal sectional view showing a conventional automobile switch to which a movable contact plate is applied.

FIG. 5 is a view similar to FIG.
It is a longitudinal cross-sectional view of the state seen from the direction.

FIG. 6 is a side view showing a contact structure of a conventional movable contact plate.

FIG. 7 is a side view showing a state where the movable contact plate is initially pressed and comes into contact with a fixed contact.

FIG. 8 is a side view showing a state in which the movable contact plate is pressed slightly over stroke.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Movable contact plate 2 Tip part 3 Fixed contact 3c Surface 4 Contact 12 Pressing part

Claims (1)

[Claims] 1. A movable contact, wherein a base end of a movable contact plate is fixed, a distal end of the movable contact plate faces a fixed contact, and the movable contact plate is pressed to contact the distal end with the fixed contact. In the contact structure of a plate, a curved contact is formed at the tip of the movable contact plate, and the contact slides on the surface of the fixed contact when the movable contact plate is pressed. Contact plate contact structure.