Shock sensor

摘要

PCT No. PCT/JP93/00790 Sec. 371 Date Jun. 7, 1994 Sec. 102(e) Date Jun. 7, 1994 PCT Filed Jun. 14, 1993 PCT Pub. No. WO93/26026 PCT Pub. Date Dec. 23, 1993A shock sensor capable of detecting a shock in a number of directions includes a reed switch, which is fixed inside a body and has a reed contact part with is magnetically changed from a first to a second state by way of a magnet, which is fixed inside the body at a specified distance from the reed switch. A shield member, having a sufficiently large area, prevents the magnetic force of the magnet from affecting the reed contact part when the shield member is in its regular position. A resilient member, in a normal state, keeps the shield member at its regular position between the reed contact part and the magnet, at which the reed contact part is kept in the first state. When a shock is applied to the shock sensor, the resilient member allows the shield member to move to a position where the reed contact part changes over to the second state. In a second embodiment, the magnet is movably held in the main casing at a specified distance from the reed switch. In a normal state, the position of the magnet is such that its magnetism does not affect the reed contact part. When a shock is applied to the shock sensor, the magnet moves to a second position where the reed contact part is changed over to the second state.