Shock load sensor

• US 5,535,630 A
• Filed: 03/17/1995
• Issued: 07/16/1996
• Est. Priority Date: 03/25/1994
• Status: Expired due to Fees

• Current Assignee: SMC Kabushiki Kaisha
• Original Assignee: SMC Kabushiki Kaisha
• Inventors: Miyamoto, Michikazu
• Primary Examiner(s): Chilcot, Richard
• Assistant Examiner(s): NOORI, MAX H
• Application Number:
  US08/406,051
• Time in Patent Office: 487 Days
• Field of Search: 73/11.01, 73/11.04, 73/11.07, 73/430, 73/431, 73/778, 73/774, 73/779
• US Class Current: 73/778
• CPC Class Codes: G01M 17/04 Suspension or damping
• CPC Class Codes: G01P 15/135 by making use of contacts which are actuated by a movable inertial mass

Abstract

A shock load sensor has a movable member disposed in a casing and supported by a spring or resilient member, and displacement of the movable member responsive to an undue shock load applied thereto is converted into an electrical connection or disconnection. Such an electrical connection or disconnection is indicative of the application of a shock load in excess of the resiliency of the spring or resilient member to the movable member. The shock load sensor is of a simple structure, and may be used to reliably detect a reduction in the shock absorbing capability of a shock absorber, for example.

Claims

1. A shock load sensor comprising:

a casing having an attachment surface adapted to be mounted on an apparatus;

a pair of terminals mounted on said casing;

a spring disposed in said casing;

a movable member having a predetermined weight, which is made of an electrically conductive material and disposed in said casing for displacement in response to a shock load applied in excess of a predetermined level to bring said terminals into or out of electric connection with each other for thereby producing a signal;

said movable member being supported by said spring such that an expansive restorative force of said spring urges said movable member against said terminals, said movable member being displaceable against the resiliency of said spring to bring said terminals into or out of electric connection with each other for thereby producing said signal.

2. A shock load sensor according to claim 1, wherein said shock load sensor is used to detect, based on said signal, whether the shock absorbing capability of a shock absorber mounted on said apparatus is functioning normally.

3. A shock load sensor according to any one of claims 1 or 2, further comprising load setting means for adjusting a force to hold said movable member in contact with said terminals under the resiliency of a spring, said load setting means comprising an adjustment screw supported on said casing.

4. A shock load sensor according to claim 1 or 2, further comprising load setting means for adjusting the position of an integral distal end portion of said movable member.

5. A shock load sensor according to claim 1, wherein said attachment surface lies substantially perpendicularly or parallel to the direction in which said shock load is applied.

7. A shock load sensor according to claim 1, wherein said casing is made of an electrically insulating material.

8. A shock load sensor according to claim 7, wherein said casing has a space defined therein, said movable member being housed in said space, said terminals being exposed in said space, whereby said movable member can be brought into contact with said terminals.

6. A shock load sensor comprising:

a casing having an attachment surface adapted to be mounted on an apparatus;

a pair of terminals mounted on said casing;

a spring disposed in said casing;

a movable member having a predetermined weight, which is made of an electrically conductive material and disposed in said casing for displacement in response to a shock load applied in excess of a predetermined level to bring said terminals into or out of electric connection with each other for thereby producing a signal;

said movable member being supported by said spring such that an expansive restorative force of said spring urges said movable member against said terminals, said movable member being displaceable against the resiliency of said spring to bring said terminals into or out of electric connection with each other for thereby producing said signal; and

further comprising a displacement member disposed outside of said casing for displacement in unison with said movable member, at least one of said displacement member and said movable member being made of a magnetic material.

9. A shock load sensor comprising:

a casing having an attachment surface adapted to be mounted on an apparatus;

a pair of terminals mounted in said casing;

a movable member having a predetermined weight, which is made of an electrically conductive material and disposed in said casing for displacement in response to a shock load applied in excess of a predetermined level;

said movable member comprising a swingable body maintained in constant contact with one of said pair of terminals, said movable member swinging in response to said shock load to cause said movable member to contact the other of said terminals, thereby bring said terminals into or out of electric connection with each other for thereby producing a signal.

11. A shock load sensor according to claim 9, wherein said shock load sensor is used to detect, based on said signal, whether the shock absorbing capability of a shock absorber mounted on said apparatus is functioning normally.

17. A shock load sensor according to claim 11 further comprising load setting means for adjusting a force to hold said movable member in contact with said terminals under the resiliency of a spring, said load setting means comprising an adjustment screw supported on said casing.

10. A shock load sensor comprising:

a casing having an attachment surface adapted to be mounted on an apparatus;

a pair of terminals mounted on said casing;

said casing having a space defined therein; and

a movable member having a predetermined weight housed in said space, which is made of an electrically conductive material and disposed in said casing for displacement in response to a shock load applied in excess of a predetermined level to bring said terminals into or out of electric connection with each other for thereby producing a signal, wherein said terminals are exposed in said space and provided in parallel side-by-side relation to each other on one wall surface of said casing and in opposing relation to a connecting surface of said movable member, wherein said movable member is movable into and out of contact with said pair of terminals.

12. A shock load sensor according to claim 10 or 11, further comprising a spring disposed in said casing, said movable member being supported by said spring for displacement against the resiliency of said spring to bring said terminals into or out of electric connection with each other for thereby producing said signal.

13. A shock load sensor according to claim 10 further comprising load setting means for adjusting a force to hold said movable member in contact with said terminals under the resiliency of a spring, said load setting means comprising an adjustment screw supported on said casing.

14. A shock load sensor according to claim 10 or 11, further comprising load setting means for adjusting the position of an integral distal end portion of said movable member.

16. A shock load sensor according to claim 10, wherein said casing is made of an electrically insulating material.

18. A shock load sensor according to claim 12 further comprising load setting means for adjusting a force to hold said movable member in contact with said terminals under the resiliency of a spring, said load setting means comprising an adjustment screw supported on said casing.

15. A shock load sensor comprising:

a casing having an attachment surface adapted to be mounted on an apparatus;

a pair of terminals mounted on said casing; and

a movable member having a predetermined weight, which is made of an electrically conductive material and disposed in said casing for displacement in response to a shock load applied in excess of a predetermined level to bring said terminals into or out of electric connection with each other for thereby producing a signal, wherein said terminals are provided in parallel relation to each other and to a connecting surface of said movable member; and

further comprising a displacement member disposed outside of said casing for displacement in unison with said movable member, at least one of said displacement member and said movable member being made of a magnetic material.