JPH0577770U - Acceleration detection device - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent chattering of the lead switch when a shock is applied and to improve the operational stability of the airbag device. A read switch 3, a spring 4 that elastically presses a magnet ring 5, and an elastic stopper 8 formed of an elastic material that prevents chattering are arranged coaxially.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an acceleration detection device, and more particularly to a chattering prevention mechanism when an impact is applied in an acceleration sensor that operates an airbag device installed in a passenger car only when a certain impact is applied.

[0002]

[Prior Art]

 The present applicant has previously proposed an acceleration detection device in Japanese Patent Application No. 2-91390. As shown in FIG. 3, this acceleration detecting device is provided with a lead switch D, a magnet ring E, a spring H arranged so that one end of the magnet ring E is in contact with the magnet ring E, and an elasticity of a spring H. It is composed of a lid G that is attached by the above.

In this structure, as shown in FIG. 2A, when an acceleration G1 of a certain level or more is applied, the magnet ring E moves in the direction of the lid G against the elastic force of the spring H. .. When the magnet ring E moves to the switch portion of the lead switch D, the lead switch D closes, the airbag device operates, and the safety of the driver or occupant can be secured. ..

[0004]

[Problems to be solved by the device]

 In this acceleration detecting device, the magnet ring E moves on the lead switch D against the elasticity of the spring H when the acceleration G1 is applied, but when the repulsive force of the spring H becomes larger than the acceleration G1, the magnet ring E The ring E is pushed back by the spring H. That is, a so-called chattering phenomenon occurs in which the magnet ring E reciprocates on the lead switch D by the spring H and the acceleration.

Therefore, there is a problem in that the airbag device becomes uncertain and the safety of the occupant cannot be ensured.

Therefore, an object of the present invention is to provide an acceleration detecting device having a simple structure and capable of preventing a chattering phenomenon in which a magnet ring reciprocates on a lead switch when acceleration is applied.

[0007]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention arranges a magnet ring and a spring on the outer circumference of a lead switch coaxially and elastically restrains the movement of the magnet ring due to detected acceleration. It is characterized by having a stopper made of material.

[0008]

[Action]

 According to this invention, when acceleration is applied, the magnetic ring moves against the elasticity of the spring to operate the lead switch, but after moving for a predetermined distance, it hits the stopper made of elastic material. It is restrained without bouncing. Therefore, a desired current can be stably supplied without chattering.

[0009]

【Example】

 Next, an embodiment of the present invention will be described with reference to FIG.

In FIG. 1, a lead switch 3 is arranged on the tubular portion 2 of the first case 1. In the lead switch 3, a pair of switch parts made of magnetic material is arranged in a container such as glass or ceramic.

On the other hand, in the tubular portion 2, for example, an annular magnet ring 5 having an angular cross section is arranged so as to be substantially concentric with the tubular portion 2.

The coil-shaped spring 4 is arranged on the outer peripheral portion of the tubular portion 2, and one end thereof is arranged to elastically press the magnet ring 5 by the lid 7.

In this configuration, as shown in FIG. 2A, when a certain acceleration G1 is applied, the magnet ring 5 moves toward the lid 7 against the elastic force of the spring 4. When the magnet ring 5 moves to the switch part of the lead switch 3, the lead switch 3 closes and then the magnet ring 5 softly collides with the elastic stopper 8 made of an elastic material that prevents chattering. Therefore, it does not return until the acceleration decreases, so chattering is suppressed.

In the above embodiment, the lid 7 may be formed integrally with the second case 6.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of the present invention.

2A is a diagram showing a state where acceleration is applied, and FIG. 2B is a diagram showing a chattering state.

FIG. 3 is a side sectional view showing a conventional example.

[Explanation of symbols]

 1 1st case 2 Cylindrical part 3 Lead switch 4 Spring 5 Magnet ring 6 2nd case 7 Lid body 8 Elastic stopper

Claims (1)

[Scope of utility model registration request] 1. An acceleration detecting device comprising a magnet ring, a spring, and a lead switch in which a spring and a stopper made of an elastic material for preventing chattering are coaxially arranged on an outer peripheral portion.