JPH085076Y2 - Shock sensing device - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial field of application) The present invention relates to an impact sensing device for igniting an ignition element, for starting an impact safety system such as an air bag or a seat belt tensioner. Used as a sensor.

(Prior Art) Japanese Patent Application Laid-Open No. 60-24
The one shown in Japanese Patent No. 8456 is known. This is because the movement of the sensing weight causes the rod to be pressed and rotated against the biasing force of the spring, and the rotation of the rod rotates the rotating shaft to release the engagement between the rotating shaft and the ignition pin. Was moved by the urging force of the spring.

(Problems to be solved by the invention) However, the impact sensing device described above utilizes the fluid damper effect due to the clearance between the sensing weight and the housing to impact (instantaneously It is designed to prevent malfunctions so that it will not operate when exposed to a shock. For this reason, there is a disadvantage that the characteristics change due to various conditions such as a temperature change, and stable performance cannot always be obtained.

Therefore, an object of the present invention is to make it possible to prevent malfunctions that always have stable performance regardless of various conditions such as temperature changes.

[Constitution of device]

(Means for Solving the Problems) Technical means taken in the present invention for solving the above technical problems include a housing, a weight provided in the housing and having a large diameter portion, and an initial weight. And a resistance member disposed between the housing and the weight, and resists the biasing force of the spring, the frictional force of the resistance member, and the moment of inertia of the large diameter portion. By moving the weight, the impact is detected and the ignition element is ignited.

(Operation) The above technical means operates as follows. Impact is sensed by the movement of the weight against the urging force of the spring, the frictional force of the resistance member, and the moment of inertia of the large diameter portion, thereby preventing malfunction due to the impact of extremely minute time such as traveling on a rough road. Therefore, there is no characteristic change due to various conditions such as temperature change, and stable performance can always be obtained.

Embodiment An embodiment of the present invention will be described below with reference to the accompanying drawings.

A first embodiment will be described with reference to FIGS. 1 to 4.

As shown in FIGS. 1 to 4, the housing 1
A weight 2 is arranged inside. The weight 2 has a pair of disc-shaped large diameter portions 2a, a cam portion 2b formed between the large diameter portions 2a, and a shaft portion 2c formed outside the large diameter portion 2a.
It consists of and. A groove portion 1a is formed in the housing 1, and the groove portion 1a engages with the shaft portion 2c so that the weight 2
Is rotatably supported along the groove 1a.

A resistance member 3 is arranged between the housing 1 and the weight 2. The resistance member 3 includes a rack gear portion 3a formed in the housing 1 in parallel with the rotational sliding direction of the weight 2, and a pinion gear formed between the large diameter portion 2a of the weight 2 and the shaft portion 2c and meshing with the rack gear portion 3a. And part 3b. This rack gear part 3a Pinion gear part 3b
The frictional force generated by meshing with the vehicle absorbs shocks during extremely short periods of time, such as when driving on rough roads (damper effect), and prevents malfunctions due to shocks during extremely short periods of time. As described above, since the damper effect is generated by disposing the resistance member 3, it is possible to always obtain stable performance without characteristic change due to various conditions such as temperature change. Further, the above function can be performed regardless of the dimensional accuracy, and the man-hour and cost can be reduced. Furthermore, since the large diameter portion 2a is formed on the weight 2, the damper effect can be further generated by the moment of inertia by the large diameter portion 2a, and the reliability can be made higher.

As shown in FIG. 5, the resistance member 3 has plate-shaped friction members 8 and 9 disposed on the housing 1 and the weight 2, respectively, and the friction member 8 and the friction member 9 are rotated by sliding the weight 2. The damper effect may be generated by frictional force. Further, as shown in FIG. 6, a string-like member 10 is arranged between the weight 2 and the housing 1, and the weight 2 is wound around the winding member.
11 may be formed, and the damper effect may be generated by the resistance when the string-shaped member 9 is wound by the rotational slide of the weight 2.

In the housing 1, the firing lever 4 is a pin 5
It is rotatably supported by. A firing pin 4a is formed at the tip of the firing lever 4 and collides with the detonator 6 when the firing lever 4 rotates. An engagement portion 4b that engages and disengages with the cam portion 2b is formed on the firing lever 4, and the rotation of the firing lever 4 is restricted by the engagement between the cam portion 2b and the engagement portion 4b. Hooking portions 1b and 4c are formed on the housing 1 and the firing lever 4, respectively. The spring 7 is always biased in the direction of the collision with the detonator 6, and the spring 7 keeps the position of the weight 2 and rotates the firing lever 4 after the engagement between the cam portion 2b and the engaging portion 4b is released. There is a momentum.

The impact sensing device is arranged in two sets so as to be point-symmetrical, and the inertial load when mounted on the steering wheel hud or the like is input as uniformly as possible to improve redundancy.

 Next, the operation will be described.

In FIG. 2, when an impact is applied from the direction A shown in FIG. 2, the inertia force causes the weight 2 to mesh with the rack gear portion 3a and the pinion gear portion 3b so that the shaft portion 2c is guided in the groove portion 1a, as shown in FIG. To rotate and slide. The rotation of the weight 2 disengages the cam portion 2b from the engagement portion 4b as shown in FIG. As a result, the firing lever 4 can be rotated, and is rotated by the urging force of the spring 7 to rotate the firing pin.
4a collides with the detonator 6.

The firing lever 4 may be an electrical switch 12 as shown in FIGS. 7 and 8. In this case, the leaf spring 13 and the leaf spring 14 are disposed in the housing 1 so that they can come into contact with each other, and when an impact is applied from the direction A shown in FIG. Thus, as shown in FIG. 6, the leaf springs 13 and 14 come into contact with each other, and it is sensed that an impact is applied.

[Effect of device]

According to the present invention, a weight having a large diameter portion, a spring for holding the weight at an initial position, and a resistance member arranged between the housing and the weight are provided. Also, since the impact is sensed by the movement of the weight against the moment of inertia due to the large diameter portion, there is no characteristic change due to various conditions such as temperature change and it is possible to always obtain stable performance. In addition, it is possible to reduce the number of steps and costs as compared with the related art, and prevent malfunctions due to impact during an extremely minute time such as when traveling on a bad road.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial sectional plan view of an impact sensing device according to the present invention,
FIG. 2 is a sectional view of FIG. 1, FIGS. 3 and 4 are sectional views showing an operating state, and FIGS. 5 and 6 are sectional views showing modified examples of the resistance member, FIGS. 7 and 8. The drawing is a sectional view showing a second embodiment. 1 …… Housing, 2 …… Weight, 3 …… Resistance member, 7 ……
Spring, 2a ... Large diameter part.

Claims (1)

[Scope of utility model registration request] 1. A housing, a weight provided in the housing and having a large diameter portion, a spring for holding the weight at an initial position, and a resistance member arranged between the housing and the weight. And an impact sensing device for sensing an impact and igniting an ignition element by the movement of the weight against the biasing force of the spring, the frictional force of the resistance member, and the moment of inertia of the large diameter portion.