Acceleration detector switch having magnetic biased conductive oscillating controller

• US 4,028,516 A
• Filed: 01/08/1975
• Issued: 06/07/1977
• Est. Priority Date: 01/14/1974
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd., Nissan Motor Co., Ltd.
• Original Assignee: Hitachi, Ltd., Nissan Motor Co., Ltd.
• Inventors: Hasegawa, Akira, Ushiku, Kenichi, Tanigami, Takahiko, Tsujimura, Harutoshi, Hirashima, Kenzo
• Primary Examiner(s): Scott, James R.
• Application Number:
  US05/539,425
• Time in Patent Office: 881 Days
• Field of Search: 200/61.45 R, 200/61.45 M, 200/61.48-61.53, 200/159 A, 200/244-246, 200/249-251, 180/91, 180/105, 280/150 AB
• US Class Current: 200/61.45M
• CPC Class Codes: G01P 15/135 by making use of contacts which are actuated by a movable inertial mass
• CPC Class Codes: H01H 35/14 Switches operated by change of acceleration, e.g. by shock or vibration, inertia switch wherein the liquid constitutes a contact of the switch H01H29/002

Abstract

An acceleration detector using a combination of a bar magnet, an inertial substance or body and a fixed contact, in which the inertial substance is secured to the free end of a plate-spring supported in a cantilever fashion and having a pair of opposing curved portions.

Claims

1. An acceleration detector, wherein a magnet and a fixed contact member are mounted on a base mount, and an inertial body serving as a movable contact and located between said magnet and said fixed contact is secured to the free end of a plate-spring, while the other end of said plate-spring is secured to said base mount, whereby when an acceleration of a predetermined magnitude is applied to said inertial body, said inertial body is biased against an attracting force of said magnet to contact said fixed contact member, thereby closing an electric circuit, characterized in that the widthwise direction of said plate-spring is perpendicular to the line extending between the center of said magnet and the center of said fixed contact, and that said plate-spring includes at least a pair of opposing curved portions formed between the fixed end and free end thereof, wherein said pair of curved portions are disposed in facing relationship to one another with the respective centers of curvature of said pair of facing curved portions being located in facing relationship to the same surface of said plate-spring.

2. An acceleration detector as set forth in claim 1, wherein said free end of said plate-spring is disposed along a second line extending perpendicular to the first line between said magnet and said fixed contact, said second line being disposed in the vicinity of and parallel to a third line extending along a center line between tangential lines to said respective pair of curved portions perpendicular to said first line.

3. An acceleration detector as set forth in claim 2, wherein said pair of curved portions of said plate-spring have the respective center of curvature of each of said curved portions disposed in the direction of said third line.

4. An acceleration detector as set forth in claim 3, wherein said plate-spring is a configured strip secured in cantilever fashion to said base mount.

5. An acceleration detector as set forth in claim 2, wherein said second line coincides with said third line.

6. An acceleration detector as set forth in claim 5, wherein said plate-spring is a configured strip secured in cantilever fashion to said base mount.

7. An acceleration detector as set forth in claim 1, wherein said plate-spring is a configured strip secured in cantilever fashion to said base mount.

8. An acceleration detector wherein a magnet and a fixed contact member are mounted on a base mount, and an inertial body serving as a movable contact and located between said magnet and said fixed contact is secured to the free end of a plate-spring, while the other end of said plate-spring is secured to said base mount, whereby when an acceleration of a predetermined magnitude is applied to said inertial body, said inertial body is biased against an attracting force of said magnet to contact said fixed contact member, thereby closing an electric circuit, characterized in that the widthwise direction of said plate-spring is perpendicular to a first line extending between the center of said magnet and the center of said fixed contact, and that said plate-spring consists of:

a first linear portion extending from the fixed end of said plate-spring at a right angle to the fixed end surface of said base mount;

a first curved portion continuous with the end of said first linear portion and inscribing a quarter circle;

a second linear portion continuous with the end of said first curved portion and extending in a tangential direction thereof;

a second curved portion continuous with the end of said second linear portion and inscribing a half circle which faces said first curved portion;

a third linear portion continuous with the end of said second curved portion and extending in parallel with said second linear portion; and

a fourth linear portion continuous with the end of said third linear portion in a direction at a right angle to said second linear portion but in parallel with said first linear portion;

while the lengths of said first and second linear portions and the radii of curvatures of said first and second curved portions have the substantially same values which approximate each other, the length of said third linear portion being slightly smaller than said values and the length of said fourth linear portion being slightly greater than said values.

9. An acceleration detector as set forth in claim 8, wherein said plate-spring further includes at its fixed end an extension along the fixed end surface of said base mount, said extension being secured to said base mount through the medium of a holding member that has a length corresponding to the extension.

10. An acceleration detector as set forth in claim 8, wherein said fourth linear portion of said plate-spring is disposed along a second line perpendicular to said first line, said second line being disposed in the vicinity of a third line extending along a center line between said first linear portion of said plate-spring and a tangential line to said second curved portion extending perpendicular to said first line.

11. An acceleration detector as set forth in claim 10, wherein said second line coincides with said third line.

12. An acceleration detector as set forth in claim 10, wherein said plate-spring is a configured strip secured in cantilever fashion to said base mount.

13. An acceleration detector as set forth in claim 8, wherein the sum of said value of the length of said third linear portion and said value of said second radius of curvature is approximately equal to one-half the sum of the value of the length of said second linear portion, the value of said first radius of curvature and the value of said second radius of curvature such that said fourth linear portion is disposed along a second line extending approximately centrally between said first linear portion and a tangential line to said second curved portion perpendicular to said first line.

14. An acceleration detector as set forth in claim 13, wherein said plate-spring is a configured strip secured in cantilever fashion to said base mount.

15. An acceleration detector as set forth in claim 8, wherein said plate-spring is a configured strip secured in cantilever fashion to said base mount.