Abstract: A rotor 10 is constructed of a rotating shaft 7 and a semicylindrical rotating core 9 mounted on the shaft 7. A stator is coaxially arranged, with the rotor 10 being surrounded by a pair of annular stator coils 11 and 13 arranged one above the other in an axial direction of the rotor 10. A yoke member of the coils 11 and 13 is provided with magnetic material plates 19, 21, 23 and 25. The plates 19 and 21 for the coil 11 have halves 19A and 21A with inner peripheral portions protruding radially inwardly to approach the rotor 10, while the remaining plates 23 and 25 for the coil 13 have halves 23A and 25A with their inner peripheral portions protruding radially inwardly to approach the rotor 10. The halves 23A and 25A are oppositely disposed from the halves 19A and 21 A so as to have the coils 11 and 13 be opposite to each other in phase of the inductance as the rotor 10 rotates.

Abstract: An acceleration sensor includes a tubular casing having one open and closed by a lid of an elastic material. A magnetic member is received within a sealed space defined by the casing and the lid, and a damper liquid fills in the sealed space. The lid is fixedly connected at its outer peripheral portion to one end portion of the casing including the open end thereof. The lid is deformable away from the other end of the casing so as to absorb a thermal expansion of the damper liquid. The lid has an annular deformable diaphragm portion extending between a central tubular portion of the lid and the outer peripheral portion of the lid. For attaching the lid to the casing, the outer peripheral portion of the lid is pressed into the one end portion of the casing so as to bring the diaphragm portion into contact with the damper liquid, so that part of the damper liquid flows into the tubular portion. Subsequently, an axial bore of the tubular portion is closed by a closure member.

Abstract: An acceleration sensor includes a tubular casing having one open end closed by a lid of an elastic material. An magnetic member is received within a sealed space defined by the casing and the lid, and a damper liquid fills in the sealed space. The lid is fixedly connected at its outer peripheral portion to one end portion of the casing including the open end thereof. The lid is deformable away from the other end of the casing so as to absorb a thermal expansion of the damper liquid. The lid has an annular deformable diaphragm portion extending between a central tubular portion of the lid and the outer peripheral portion of the lid. For attaching the lid to the casing, the outer peripheral portion of the lid is pressed into the one end portion of the casing so as to bring the diaphragm portion into contact with the damper liquid, so that part of the damper liquid flows into the tubular portion. Subsequently, an axial bore of the tubular portion is closed by a closure member.

Abstract: An acceleration sensor comprises a case having defined therein at least one accommodating chamber. At least one magnetic ball is accommodated in the accommodating chamber with a radial play left between the wall surface of the accommodating chamber and the magnetic ball. The magnetic ball is magnetically attracted to a reference position in the accommodating chamber by a magnetic field generating unit. In response to acceleration, deceleration or inclination, the magnetic ball is movable in the accommodating chamber against the attracting force of the magnetic field generating unit. The movement of the magnetic ball is detected by a detector.