JPH054560A - Shock detector - Google Patents

Abstract

(57) [Abstract] [Purpose] Improving the assemblability and ensuring stable performance as shock sensing [Structure] The output member (6) and the weight (4) are separate from the housing (1). The frame (3) is supported so that all of these members are unitized independently of the housing (1) to prevent dimensional errors between the members during assembly.

Description

Detailed Description of the Invention

[0001]

[Object of the Invention]

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical shock-sensing device for firing a firing element without using electric power,
It is used as a starting sensor for impact safety systems such as air bags and seat belt tensioners.

[0003]

2. Description of the Related Art Conventionally, as this type of shock sensing device,
The one disclosed in Japanese Patent Laid-Open No. 2-249744 is known. This is a housing, a weight that is movably supported by the housing and detects an impact from the outside, moving means that is fixed to the housing and that meshes with the weight and that slides the weight by detecting an impact of a predetermined value or more, and a housing. And a firing lever which is rotatably pivotally supported and which is disengaged by the rotation slide of the weight and is rotated by the urging force of the spring.

[0004]

However, in the above-mentioned shock sensing device, the weight, the moving means and the firing lever are directly supported by the housing, and when the housing is assembled, the respective members are separately assembled in the housing. It must be done, and assembly is poor. In addition, since the housing is formed by combining a plurality of members due to its box shape, dimensional errors are likely to occur in the housing itself. For this reason, an assembly error is likely to occur between the respective members, and in the conventional device in which the performance as the impact sensing device is ensured by the dimensional management between the respective members, the performance may be adversely affected.

Therefore, the present invention provides an impact sensing device capable of improving the assemblability and ensuring stable performance.
This is a technical issue.

[0006]

[Constitution of the invention]

[0007]

The technical means taken in the present invention to solve the above technical problems is to have a frame which is supported by a housing and which supports at least a weight and an output member.

[0008]

The above technical means operates as follows. At least the weight and the output member are supported by one frame separately from the housing. As a result, all the members can be assembled in a process different from the process of assembling the housing, and the assembling property is improved. Further, since it is easy to secure the dimensional braking in the frame itself, an assembly error between the respective members is unlikely to occur, and stable performance as the impact sensing device is secured.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

The first embodiment will be described.

As shown in FIG. 1, the housing 1 has a box shape formed by combining a plurality of plate-shaped members 1a and 1b, and an impact sensing mechanism 2 is arranged in the internal space of the housing 1. It is set up.

As shown in FIGS. 1 and 2, a frame 3 is fixed to the housing 1. This frame 3
Has a pair of supporting portions 3a formed by bending one plate member and facing each other, and a flange portion 3b perpendicular to the supporting portion 3a.

The weight 4 is movably supported in the housing 1 through a pivot 5 that moves integrally, and the weight 4 has a large diameter shape centered on the pivot 5. The weight 4 is formed with a stopper pin 4a that abuts the flange portion 3b of the frame 3, and the abutment of the flange portion 3b and the stopper pin 4a sets the initial position of the weight 2 in the housing 1.

The firing lever 6 is rotatably supported by a pin 7 between the supporting portions 3a of the frame 3. Around this pin 7, there is wound a torsion spring 9, one end of which is locked to the support portion 3a and the other end of which is locked to the firing lever 6 via a collar 8. It is constantly urged in the clockwise direction shown in FIG. Further, the firing lever 6 is formed with a firing pin 6a capable of colliding with an external detonator (not shown).

A pinion gear 10 is fixed to the pivot shaft 5, and the pinion gear 1 is attached to the flange portion 3b of the frame 3.
A rack gear 11 that meshes with 0 is formed. In addition, a semi-circular cam portion 12 is formed on the pivot 5 so that it can be engaged with and disengaged from the firing lever 6.

The members of the first embodiment described above are assembled as follows.

The pinion gear 10 and the rack gear 11 are engaged with each other in an initial state in which the weight 4 is supported on the pivot 5 and the stopper pin 4a and the flange portion 3b are brought into contact with each other. Further, the firing lever 6 is supported on the frame 3 by the pin 7 via the torsion spring 9 and the cam portion 1
2 and the firing lever 6 are engaged. As a result, the weight 4 and the firing lever 6 are supported by the frame 3 and unitized. After that, all the members 4, 6, 1 are assembled in a separate step of assembling the housing 1.
The frame 3 on which 0 and 11 are supported is fixed to the housing 1, and the shock sensing mechanism 2 is arranged in the housing 1.

As described above, the firing lever 6, the pinion gear 10, the rack gear 11 and the weight 4 are supported by the frame 3 and are unitized separately from the housing 1. As a result, all the members 4, 6, 10, 11 can be assembled in a process different from the process of assembling the housing 1, and the assembling property can be improved. Further, since the frame 3 is molded from a single plate material, it is easy to ensure the dimensional accuracy by itself, so that an assembly error between the members 4, 6, 10 and 11 is unlikely to occur, and the frame 3 is stable as an impact sensing device. It is possible to secure the required performance.

The impact sensing device of the first embodiment described above operates as follows.

In the initial state of FIG. 1, the cam portion 12 and the firing lever 6 are in an engaged state, and the weight 4 is brought into contact with the stopper pin 4a and the flange portion 3b by the biasing force of the torsion spring 9. The initial state is maintained and the firing lever 6 is retained against the biasing force of the torsion spring 9 by the engagement with the cam portion 12. In this state, when a shock is applied in the direction of arrow A, the weight 2 detects the shock, and as shown in FIG. 3, the pinion gear 10 and the rack gear 11 mesh with each other to rotate and slide against the urging force of the torsion spring 9. The engagement between the cam portion 12 and the firing lever 6 is released.
As a result, as shown in FIG. 4, the firing lever 6 is rotated by the biasing force of the torsion spring 9, and the firing pin 6a is projected to strike the detonator. In this way, one action of the torsion spring 9 serves both to hold the weight 4 in the initial state and to bias the turning of the firing lever 6 after the impact is sensed. This allows
A large projecting energy of the firing pin 6a can be obtained in a small arrangement space, the number of parts can be reduced, and the device itself can be miniaturized. Also, since the weight 4 has a large diameter shape with the pivot 5 as the center,
A large moment of inertia can be taken. As a result, it is possible to improve the performance as a malfunction prevention without detecting an instantaneous impact when traveling on a rough road.

Next, a second embodiment will be described.

As shown in FIGS. 5 and 6, the weight 4 is movably supported by the pin 13 on the flange portion 3b of the frame 3 at a position offset from the center of gravity thereof. The other structure is the same as that of the first embodiment, but the pinion gear 10 and the rack gear 11 are not provided.

The members of the second embodiment described above are assembled as follows.

The weight 4 is supported on the frame 3 by the pin 13, and further, the firing lever 6 is supported on the frame 3 by the pin 7 via the torsion spring 9, and the cam portion 12 and the firing lever 6 are engaged with each other. State. As a result, the weight 4 and the firing lever 6 are supported by the frame 3 and unitized. After that, in a separate step of assembling the housing 1, the frame 3 supporting all the members 4 and 6 is fixed to the housing 1, and the impact sensing mechanism 2 is arranged in the housing 1.

As described above, the firing lever 6 and the weight 4 are supported by the frame 3 and are unitized separately from the housing 1. As a result, all the members 4, 6
Can be assembled in a step different from the step of assembling the housing 1, and assembling can be improved as in the first embodiment.
Also, as in the first embodiment, an assembly error between the members 4 and 6 is unlikely to occur, and stable performance as an impact sensing device can be secured.

Next, the operation of the second embodiment will be described.

In the initial state shown in FIG. 5, the arrow A
When a shock is applied in the direction, the weight 4 swings around the pin 20 against the biasing force of the torsion spring 9 as shown in FIG. 7 due to the shock (the first embodiment when viewed from the cam portion 12). It is rotating and sliding like the example). As a result,
As shown in FIG. 8, the engagement between the cam portion 12 and the firing lever 6 is released, and the firing lever 6 rotates by receiving the biasing force of the torsion spring 9. The subsequent operation is similar to that of the first embodiment, and has the same effect. As described above, in the second embodiment, the swing of the weight 4 provides the rotational slide of the cam portion 12. As a result, unlike the first embodiment, the pinion gear 10 and the rack gear 11 are not required, and the number of parts and the number of processing steps can be reduced.

[0028]

According to the present invention, a housing, a weight which is disposed in the housing and moves by an impact from a predetermined value or more from the outside, and a weight which is disposed in the housing and is disengaged by the movement of the weight. In an impact sensing device having an output member that moves in a projecting direction, since the impact sensing device is configured with a frame that is supported by the housing and supports at least the weight and the output member, the weight and the output member are unitized. The assembly can be performed in a process different from that of assembling the housing, and the assembling property can be improved. Further, since it is easy to ensure the dimensional accuracy of the frame itself, an assembly error between the members is unlikely to occur, and stable performance as an impact sensing device can be ensured.

Further, the weight is moved by rotating and sliding the weight by linking the weight to the frame through moving means or swinging the weight by supporting the weight on the frame at a position offset from the center of gravity. Therefore, it is possible to effectively utilize the moment of inertia in the shape of the weight in detecting an impact, and improve the malfunction prevention performance such as not detecting an instantaneous impact when traveling on a bad road.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of an impact sensing device according to the present invention.

FIG. 2 is an exploded perspective view of an impact sensing mechanism of the first embodiment.

FIG. 3 is a plan view corresponding to FIG. 1 showing the operation of the first embodiment.

FIG. 4 is a plan view corresponding to FIG. 1 showing the operation of the first embodiment continued from FIG. 3;

FIG. 5 is a cross-sectional view showing a second embodiment of the impact sensing device according to the present invention.

FIG. 6 is an exploded perspective view of the impact sensing mechanism of the second embodiment.

FIG. 7 is a plan view corresponding to FIG. 5 showing the operation of the second embodiment.

FIG. 8 is a plan view corresponding to FIG. 5, showing an operation subsequent to FIG. 7 of the second embodiment.

[Explanation of symbols]

1 housing 3 frames 4 weights 6 Fire lever (output member) 10 Pinion gear (moving means) 11 Rack gear (moving means)

Claims (3)

[Claims] 1. A housing, a weight which is disposed in the housing and moves by an impact from a predetermined value or more from the outside, and a weight which is disposed in the housing and disengaged by the movement of the weight to move in a protruding direction. An impact sensing device having an output member for controlling the impact sensing device, comprising: a frame supported by the housing and supporting at least the weight and the output member. 2. The impact sensing device according to claim 1, wherein the movement of the weight is a rotary slide movement due to the weight being linked to the frame through a moving means. 3. The impact sensing device according to claim 1, wherein the movement of the weight is a swinging motion caused by supporting the weight on the frame at a position offset from the center of gravity.