Abstract: An apparatus for monitoring the tire interior by supplying electric power from a power source on a chassis side to a tire-side sensor via a power-supplying coil and a power-receiving coil, and by transmitting a sensor output via a signal-transmitting coil and a signal-receiving coil. The signal-transmitting coil and the power-receiving coil, as well as the signal-receiving coil and the power-supplying coil, are respectively arranged to be substantially concentric in a respective substantially identical plane, and an electromagnetic shielding is provided so as to prevent noise from being mixed in the sensor output. The arrangement makes compact a coupling portion on the chassis side and a coupling portion on the tire side.

Abstract: A tire wheel includes a pair of flanges provided on both axial ends, respectively, a pair of bead seats extending from the flanges axially inwardly, a well provided between these bead seats and concaved radially inwardly of the bead seats, and at least one hump circumferentially extending provided between the well and one of the bead seats and having a seat side inclined surface on a side of the relevant beat seat and a well side inclined surface on a side of the well to form a top as a boundary between both the inclined surfaces. The seat side inclined surface is formed by part of a conical surface intersecting at an angle of 5.degree.-35.degree. with a straight line in parallel with a tire axis. A concaved obtuse corner is formed at a boundary between the seat side inclined surface and the relevant bead seat.

Abstract: A tire wheel includes a pair of flanges provided at both axial ends, a pair of bead seats axially inwardly extending from the flanges, a well provided between the bead seats and concaved radially inwardly of the bead seats, and a hump provided between the well and at least one of the bead seats. The hump circumferentially extends and has a seat side inclined surface on the side of the relevant bead seat and a well side inclined surface on the side of the well on both sides of a crest of the hump. The seat side inclined surface of the hump includes an inclined surface continuous to the crest of the hump and an inclined surface rising from the relevant bead seat. A concaved corner having an obtuse angle is provided between the relevant bead seat and the inclined surface rising from the relevant bead seat.

Abstract: A pressure switch for use in a device for alarming the reduction of pneumatic pressure of vehicle tire is disclosed. The switch comprises a base board, a bellofram secured to the base board and having conductive coating of one electric contact applied to the inner surface and the outer surface thereof and having both bellows and diaphragm characteristics, a housing provided to enclose the bellofram and for defining a hermetic chamber, and a conductor provided at inner portion and outer portion of the bellofram near the center of the diaphragm portion thereof and for forming another electric contact. A back pressure is applied to the inner portion or outer portion of the bellofram against the pneumatic pressure of a vehicle tire.

Abstract: A pressure switch for use in a device for alarming the reduction of pneumatic pressure of vehicle tire is disclosed. The switch comprises a base board, a bellofram secured to the base board and having conductive coating of one electric contact applied to the inner surface and the outer surface thereof and having both bellows and diaphragm characteristic, a housing provided to enclose the bellofram and for defining a hermetic chamber, and a conductor provided at inner portion and outer portion of the bellofram near the center of the diaphragm portion thereof and for forming another electric contact. A back pressure is applied to the inner portion or outer portion of the bellofram against the pneumatic pressure of a vehicle tire.