Patent · US Expired

Shock sensor

US5326945A · kind A · utility

21Cited by
6References
7Claims
0Family size

Assignees

Inventors

Key dates

Filing dateDec 2, 1992
Grant dateJul 5, 1994
Priority date
Expiry dateDec 2, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H35/147
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

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…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.