The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 05, 1994
Filed:
Dec. 02, 1992
Noriyuki Gotoh, Miyagi, JP;
Yasunori Ohtuki, Miyagi, JP;
Naoharu Yamamoto, Miyagi, JP;
Hiroyuki Sada, Hyogo, JP;
Akihiko Kuroiwa, Hyogo, JP;
Hiroshi Moriyama, Hyogo, JP;
Tokin Corporation, Sendai, JP;
Sensor Technology Co. Ltd., Kobe, JP;
Abstract
To detect an impact due to a shock with high precision and stability, a shock sensor is employed which provides a sufficiently long closure interval of a contact of a reed switch (1) enough to carry out signal processing. A gap between an outer surface of a magnet (2) and an inner wall (8) of a housing (7) defining a passage for the magnet (2) comprises a first gap (G1) between a stationary position and an activating position and a second gap (G2) between the activating position and a stop position. The inner wall (8) is formed so that the first gap (G1) is greater than the second gap (G2). The velocity of the magnet (2) is lower when travelling in the second gap (G2) than the velocity in the first gap (G1) because air resistance is greater in the second gap (G2). Accordingly, the closure interval is increased. Alternatively, the closure interval of the contact of the reed switch (1) is adjusted by first and second coil springs (3, 49) which independently urge first and second magnets (2, 48) in an anti-impact direction, respectively. To cope with various collision modes, spring constants (k1, k2) of the first and the second coil springs (3, 49) and masses (m1, m2) of the first and the second magnets (2, 48) are selected so that the velocity of shock-responsive movement is different between a first group comprising the first magnet (2) and the first coil spring (3) and a second group comprising the second magnet (48) and the second coil spring (49).