JPH0441537Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a switch for detecting opening/closing of an automobile hood.

(Prior art) Automobiles are equipped with a switch that detects the opening and closing of the hood.This switch has a fixed contact and a movable contact facing each other on the vehicle body, and the movable contact responds to the opening and closing of the bonnet. The contact is opened when the bonnet is closed, and closed when the bonnet is open.

(Problem that the invention attempts to solve) The bonnet is not something that is opened and closed frequently;
The contacts of the open/close detection switch remain closed for a long period of time and are exposed to the relatively harsh environment around the engine. For this reason, the detection switch has a problem in that the contact surface is corroded or dirt or dust is deposited on the contact surface, resulting in poor conductivity, resulting in low detection reliability.

Therefore, for example, Japanese Utility Model Application Publication No. 55-72731 proposes a structure in which one end of a movable contact is bent diagonally and brought into contact with a fixed contact, thereby wiping the contact portion. However, in order to perform sufficient wiping, the wall thickness of the movable contact is made thinner.
Moreover, it had to be made of a spring material, which resulted in the problem of poor durability.

The present invention was devised in view of these problems, and an object of the present invention is to provide a hood opening/closing detection switch that is highly reliable and durable.

(Means for solving the problem) In order to solve the above problem, the present invention includes a base that is attached to the vehicle body and has a fixed contact portion, and a base that is made of an insulating material and is slidable in the axial direction. It has a detection shaft that is supported by the base so as not to be rotatable around the axis and responds to opening and closing of the bonnet, and a movable contact part that contacts and separates from the fixed contact part at the tip, and that moves integrally with the detection shaft in the axial direction. , a movable member that can be rotated by a predetermined angle with respect to a detection axis, and a movable contact portion that urges the movable member in the axis and torsion direction by hooking one end to the movable member and the other end to the base. a coil spring that contacts the fixed contact portion, one of the fixed contact portion and the movable contact portion is formed in a triangular shape and the other is formed in a notched groove shape, so that the coil spring contacts the fixed contact portion when both contact portions are closed. Due to the biasing force in the axial direction, the inclined end face of one triangular contact part and the edge of the other notched contact part slide, and the movable member resists the biasing force in the torsional direction of the coil spring. It is designed to rotate in the anti-twisting direction.

(Function) According to the above configuration, when the bonnet is closed and the contacts are in the open state, the movable contacts are located at a position deviated from the normal contact closing position due to the biasing force in the torsional direction of the coil spring.

When the bonnet is opened, the movable member moves toward the fixed contact portion due to the axial biasing force of the coil spring. When the movable contact part of the movable member contacts the fixed contact part, the movable contact part slides along the inclined end surface with respect to the fixed contact part against the torsional biasing force of the coil spring, and the regular contact Stops in closed position. When sliding on this inclined end face, the corrosion film, dirt, dust, etc. formed on the contacts are removed.

(Example) Next, an example of the present invention will be described with reference to the accompanying drawings.

1 to 3 show a bonnet opening/closing detection switch according to the present invention, which generally consists of a base 1, a detection shaft 2, a movable member 3, and a coil spring 4.

The base 1 is made of a conductive material and is formed by cutting and raising an upper support piece 5 and a lower support piece 6 such that they face each other. The upper support piece 5 includes
An occluded hole 7 is formed through which a detection shaft 2 (described later) is inserted, and a U-shaped fixed contact portion 8 is formed on the edge of the hole 7, with which a movable contact portion 15 of a movable member 3 (described later) engages and contacts. It is formed by cutting out. Further, a support member 9 made of an insulating material is attached to the lower support piece 6, and a through hole 10 through which a detection shaft 2 (described later) is inserted is located on the same center line as the hole 7 of the upper support piece 5. is formed.

The detection shaft 2 is made of an insulating material and has a drum-shaped cross section with parallel surfaces except for the upper end.
It fits into the hole 7 of the upper support piece 5 and the through hole 10 of the support member 9 of the lower support piece 6, so that it can slide only in the axial direction and cannot rotate around the axis. Further, a pair of elastic pieces 1 are attached to the lower end of this detection shaft 2.
1 and 11, and claw portions 12 and 12 are provided at their tips, into which a movable member 3, which will be described later, is fitted and locked. The portion of the detection shaft 2 protruding from the base 1 is fitted with a boot 13, as shown in FIG.

The movable member 3 is made of a conductive material and has a U-shape, and as shown in FIG. As shown in FIG. 1, the elastic pieces 11, 11 at the lower end of the detection shaft 2 are fitted into holes (not shown) drilled in the lower piece, and the claws 12, 12 thereof are locked and attached. - As shown in FIG. 8, it is rotatable around the detection axis 2 by a predetermined angle. Further, as shown in FIGS. 3 and 6, a triangular movable contact portion 15 is bent and provided on the upper piece of the movable member 3, and the tip of the movable contact portion 15 is connected to the base 1. It fits into the notched groove-shaped fixed contact part 8, so that the inclined end surface and the edge of the fixed contact part 8 come into contact with each other. Note that the lower piece of the movable member 3 is connected to the lead wire 16.
It is connected to and energized.

The coil spring 4 is inserted through the detection shaft 2, has an upper end pressed against and latched onto the upper piece of the movable member 3, and a lower end pressed against a support member 9 provided on the lower support piece 6 of the base 1. The movable member 3 is latched by the movable member 3 in its axial direction and torsional direction.

The bonnet opening/closing detection switch constructed as described above is mounted on the vehicle body side of an automobile so that the upper end of the detection shaft 2 faces the bonnet, is pushed down by the bonnet when the bonnet is closed, and is detached from the bonnet when the bonnet is opened.

When the bonnet is opened, as shown in Figure 3,
The detection shaft 2 and the movable member 3 are pushed up by the urging force of the coil spring 4, and the movable contact portion 1 of the movable member 3
5 engages with the fixed contact portion 8 of the base 1 and is in a contact closed state. As a result, the movable member 3 and the base 1
is electrically conductive, and a display board installed inside the vehicle lights up to indicate that the bonnet is open.

When the bonnet is closed, the detection shaft 2 is pushed down by the bonnet, and the movable member 3 moves downward accordingly. At this time, the movable member 3 is moved by the coil spring 4
Since the contacts are biased in the torsional direction by Then, as shown in FIG. 7, the inclined end surface of the movable member 3 comes into sliding contact with the fixed contact portion 8 until the counterclockwise rotation of the movable member 3 is regulated by the detection shaft 2.

As shown in FIGS. 4 and 7, after the rotation of the movable member 3 is restricted, it moves downward while maintaining the restricted state, and the contact opens, and the display provided on the inside of the vehicle The lights on the board, etc. are turned off and the bonnet is confirmed to be closed, resulting in the state shown in FIGS. 5 and 8.
Therefore, when the bonnet is closed, the movable contact portion 15
The tip of the contact is slightly eccentric from the normal contact closing position shown in FIG.

Next, when the bonnet is opened, the detection shaft 2 and the movable member 3 are moved upward from the state shown in FIG. 5 by the biasing force of the coil spring 4. and,
When the inclined end surface of the movable contact portion 15 contacts the fixed contact portion 8 as shown in FIG. 4, the movable contact portion 15
moves to the left in FIG. 4 (rotates clockwise in FIG. 7) while slidingly contacting the fixed contact portion 8 against the torsional biasing force of the coil spring 4, and eventually,
As shown in Fig. 3, the vehicle stops with both inclined end surfaces in contact with the fixed contact portion 8, the contacts are completely closed, the display board installed inside the vehicle lights up, and the bonnet is opened. Is displayed.

The sliding contact between the inclined end face of the movable contact portion 15 and the fixed contact portion 8 in this manner prevents the contact from forming an oxidized film, a corrosion film, etc.
Even if dust has accumulated, it will be rubbed off and will not cause poor conductivity.

In the above embodiment, the movable contact portion 15 was formed in a triangular shape with an inclined end face, and the fixed contact portion 8 was formed in a notched groove shape. The movable contact portion 15 may be formed in the shape of a cutout groove.

(Effect of the invention) As is clear from the above explanation, according to the invention, the fixed contact part and the movable contact part come into contact and separate by sliding on the inclined end surface, so even if the open state continues for a long time, the contact Even if a corroded film or dust is present, these will be rubbed off and will not cause poor conductivity, improving reliability. In addition, since the inclined end face of the triangular contact portion and the notched groove contact portion are in sliding contact, the thickness of the triangular contact portion can be increased to improve durability. There is.

[Brief explanation of drawings]

Fig. 1 is a front view of a bonnet open/close detection switch according to the present invention, Fig. 2 is a plan view of Fig. 1, and Fig. 3 is a front view of a bonnet open/close detection switch according to the present invention.
Figures 5 to 5 are cross-sectional views taken along the - line in Figure 1, showing sequentially from the closed state to the open state of the contacts, Figure 6 is a cross-sectional view taken along the - line in Figure 3, and Figure 7 is a cross-sectional view taken along the - line in Figure 4. 8 is a sectional view taken along the line -- in FIG. 5. DESCRIPTION OF SYMBOLS 1...Base, 2...Detection axis, 3...Movable member, 4...Coil spring, 8...Fixed contact part, 15
...Movable contact part.

Claims (1)

[Scope of claim for utility model registration] It is attached to the vehicle body and is made of a base having a fixed contact and an insulating material, is slidable in the axial direction and is supported by the base without being able to rotate around the axis, and is used to open and close the bonnet. a detection shaft that responds to the detection shaft; and a movable member that has a movable contact portion at its tip that contacts and separates from the fixed contact portion, moves integrally with the detection shaft in the axial direction, and is rotatable by a predetermined angle with respect to the detection shaft. , a coil spring having one end hooked to the movable member and the other end hooked to the base to bias the movable member in its axial and torsional direction to bring the movable contact portion into contact with the fixed contact portion; One of the contact portion and the movable contact portion is formed in a triangular shape and the other in a notched groove shape, and when both contact portions are closed, the biasing force in the axial direction of the coil spring causes one of the triangular shaped contact portions to The inclined end face and the edge of the other notched groove-shaped contact portion slide, and the movable member rotates in the counter-torsional direction against the torsional biasing force of the coil spring. Bonnet open/close detection switch.