JPS6116529Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an acceleration sensor mounted on a vehicle or the like to detect acceleration.

In conventionally used acceleration sensors, an inertial body that receives acceleration slides inside a housing and opens and closes contacts to detect acceleration.

Therefore, when used for a long period of time, wear occurs between the inner surface of the housing and the inertial body due to vehicle vibration, etc., increasing the frictional resistance against the movement of the inertial body, and the wear of the contacts increases, which can lead to malfunction. It is the cause of the invitation.

The present invention takes the above facts into consideration and aims to provide an acceleration sensor that can always be opened and closed reliably even when used for a long period of time.

The acceleration sensor according to the present invention has a structure in which the inertial body moves within the cavity of the housing by rolling rollers, so the movement resistance between it and the housing is reduced, and the movable contact that comes into contact with and separates from the fixed contact has an inertial force. Since it is pivoted to the body, wear between the contacts is also reduced, ensuring reliable operation at all times.

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

The acceleration sensor 10 shown in FIGS. 1 to 4 has a flange 14 projecting from the upper part of a housing 12, which is fixed to a vehicle body through a mounting hole 16 thereof.

This housing 12 is formed with a cavity 18 that is open at one end. The cavity 18 is a rectangular parallelepiped-shaped space surrounded by a top 20, a bottom 22, a back 24, and a pair of opposing sides 26, 28 of the housing 12. After the inertial body 30 is inserted into the cavity 18, the front surface of the opening is closed with a connector housing 32, which has a pair of hook-shaped connectors protruding from the sides 26 and 28 of the housing toward the front. It is designed to be held by an arm 34. This connector housing 32 has three pairs of fixed contacts 36.
A, 36B, 38A, 38B and 40A, 40B
The tips of these fixed contacts pass through the connector housing 32 and are exposed into the cavity 18, as shown in FIG. The other ends of these fixed contacts are connected to an unillustrated connector and connected to an engine circuit and an excitation circuit for a seatbelt unwinding lock solenoid of a seatbelt device.

The inertial body 30 inserted into the cavity has a substantially rectangular parallelepiped shape, but is smaller in size than the cavity 18, so that the inertial body 30 can move a small amount in any direction within the cavity. In particular, it is designed to be able to move largely in the direction toward and away from the side portions 26 and 28 of the housing, that is, in the inertial direction (see the directions of arrows A and B).

Near both longitudinal ends of this inertial body 30, roller grooves 42 and 44 are bored in the top and bottom surfaces, respectively, and an upper horizontal roller 46 and a lower horizontal roller 4 are formed, respectively.
The narrow diameter part of 8 is pivotally supported. These horizontal rollers 46, 48 have their outer peripheries in contact with the top 20 and bottom 22 of the cavity 18, as shown in FIG. 3, so that when the inertial body 30 moves in the inertial direction, the housing 12 can be rolled into contact.

A neutral groove 50 is provided at the center of the top of the inertial body 30.
is bored in a direction perpendicular to the inertial direction, and locking grooves 52 and 54 are bored on both sides of this neutral groove 50, respectively. A moderation roller 56 is partially accommodated in this neutral groove 50, and this moderation roller 56
is pivotally supported by a holder 58, and the holder 58 is held in a holder accommodating part 60 bored in the top part 20 of the housing 12, and inserted into a cylindrical hole 62 further bored in the bottom part of the holder accommodating part 60. The neutral groove 50 receives the biasing force of the compression coil spring 64.
is pressed against. Therefore, the moderation roller 56, the neutral groove 50, and the locking grooves 52, 54 constitute a moderation mechanism, and the inertial body 30 is normally held in the center of the cavity 18; When a large inertial force is applied in the inertial direction, the moderation roller 56 overcomes the peak between the neutral groove 50 and the locking grooves 52 and 54, thereby closing the locking groove 52 or 54.
It is adapted to hold the inertial body 30 in this position.

The cylindrical hole 62 passes through the top portion 20, and an adjustment screw 65 is screwed into it from the outside. By adjusting the amount of engagement of the adjusting screw 65, the amount of deflection of the compression coil spring 64 can be changed, and the moving force of the inertial body 30 can be adjusted.

Further, three rectangular holes 66 are bored in the front surface of the inertial body 30, and a holder 68 is accommodated in each of the rectangular holes 66. The holder 68 is biased toward the connector housing 32 by a compression coil spring 70 interposed between the holder 68 and the rectangular hole 66, and has movable contact rollers 72 pivotally supported on its front surface. These rollers 72 have their axes perpendicular, and 3
Each roller corresponds to a fixed contact 36-40. Preferably, the outer peripheries of these rollers 72 are knurled.

That is, one contact roller 7 as shown in FIG.
2 is the fixed contact 36 due to the biasing force of the compression coil spring 70
A, 36B, fixed contacts 38A, 38B, and fixed contacts 40A, 40B are closed, respectively. However, these contact rollers 72
moves in the inertial direction and the moderation roller 56 locks into the locking groove 5.
2 or 54, the fixed contacts are opened in order to separate from the fixed contacts.

Note that there is a return lever 74 at the lower front of the inertial body 30.
is extended, and the tip of this lever passes through an elongated hole 76 formed in the connector housing 32 and projects to the front. This return lever 74 can be grasped by an operator and moved in the inertial direction to return the inertial body 30 to the neutral position.

Further, a vertical roller 78 is pivotally supported on the back surface of the inertial body 30 by the same supporting means as the upper horizontal roller 46 and the lower horizontal roller 48, and the outer periphery of this roller is supported by a compression coil spring that presses the contact roller 72. 7
It contacts the back part 24 of the housing with a biasing force of 0, and is designed to roll when the inertial body moves in the inertial direction.

In the acceleration sensor 10 of this embodiment configured in this way, the housing 12 is fixed to the body of an automobile through the mounting hole 16, and the fixed contacts 36 are connected to the engine circuit and to prevent the seat belt device from unwinding. If connected to a solenoid lock device, etc.
In the event of a vehicle emergency, the inertial body 30 moves in the inertial direction (direction of arrow A or B), so three contact rollers 72 are used.
are contacts 36A and 36B, and contacts 38A and 38, respectively.
B, and 40A and 40B are opened to each other. Therefore, after a vehicle collision, the engine circuit is cut off from the battery and the seatbelt system reliably locks its unwinding, preventing a fire from occurring in the vehicle.Furthermore, the occupants are securely restrained with their seatbelts, ensuring their safety. I can guarantee it.

This inertial body 30 forms rolling contact with the housing 12 by the rollers 46, 48, and 78, so even if the inertial body moves multiple times in the inertial direction, it can always move smoothly, and the opening and closing of the contacts is done by the contacts. Since the roller 72 contacts and separates from the contacts while rolling, frictional resistance is extremely small, and as a result, wear of the contacts is extremely low.

When the mild vehicle emergency situation ends, the inertial body 3 can be removed by the occupant grasping the return lever 74 and moving it.
0 returns to the neutral position again, so the engine can be started, and the seat belt restraint of the occupant is released, so the normal driving state can be returned.

As explained above, the acceleration sensor according to the present invention has an inertial body supported by the housing via rolling rollers, and a movable contact that is pivotally supported by the inertial body and rotates with a fixed contact to open and close the contact. Furthermore, since the frictional resistance of the contacts is reduced, the inertial body can always operate under the same conditions to open and close the contacts even after multiple uses.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an embodiment of the acceleration sensor according to the present invention, Fig. 2 is a plan view of Fig. 1, Fig. 3 is a sectional view taken along the line of Fig. 2, and Fig. 4 is the right side of Fig. 1. 5 is a sectional view taken along the line of FIG. 1, FIG. 6 is an exploded perspective view, FIG. 7 is a front view of the inertial body, and FIG. 8 is a side view of FIG. 7. 10... Acceleration sensor, 12... Housing, 18... Cavity, 30... Inertial body, 36A,
36B, 38A, 38B, 40A, 40B... Fixed contact, 46, 48... Horizontal roller, 50... Neutral groove, 52, 54... Locking groove, 56... Moderation roller, 72... Contact roller, 78 ...Vertical roller.

Claims (1)

[Scope of utility model registration request] a housing, an inertial body movable in an inertial direction within a cavity of the housing, a rolling element held by the inertial body and in contact with the cavity, and the inertial body in a first position or a second position. a moderation mechanism to be held; a pair of fixed contacts projecting into the housing cavity; and a pair of fixed contacts held by the inertial body so that the outer periphery of the inertial body contacts the fixed contacts in a first position and in a second position. An acceleration sensor having a movable contact separated from at least one fixed contact.