Abstract: A cylinder lock manufacturing method wherein a plurality of cylinder locks differing in place of use but using a common key for their unlocking are taken as a group having a specific key code assigned thereto. The inner members and outer members of cylinder locks are assembled into respective cylinder locks continuously for one group after another with change of the key code. A key for each group of the locks is notched synchronously with the cylinder assembly process. The cylinder locks and the key so produced through the above processes are combined as a set.

Abstract: A locking cable for use in an antitheft device adapted to give warning in response to a change in a photo signal transmitted through an optical fiber longitudinally extending through the locking cable. The locking cable comprises a core portion including the optical fiber, a reinforcing layer concentrically disposed around the core portion and including at least one electric conductor and a plurality of reinforcing members, and a flexible hollow protective member as an outermost layer covering the electric conductor and reinforcing members in contact with the protective member. If required, a further reinforcing layer may be interposed between the core portion and the first-mentioned reinforcing member, which includes a plurality of second reinforcing members. A holder holding an end of the optical fiber and a photoelectric element in face-to-face relation to each other is axially movably arranged within a plug connected to an end of the locking cable.

Abstract: A flexible tying member for a theftproof device which is adapted to give warning in response to a change in a photo signal transmitted in an optical fiber extending through the flexible tying member. The flexible tying member has a first layer including the optical fiber and at least one electric wire connected to at least one photoelectric element, and a second layer including a reinforcing member. The flexible tying member has a coaxial structure having an inner layer formed by the above first layer, and an outer layer formed by the above second layer, or a parallel structure in which the above first and second layers longitudinally extend parallel with each other.

Abstract: A theftproof device comprising a flexible tying member, an optical fiber extending through the flexible tying member, a light emission element arranged opposite an end of the optical fiber, a light receiving element arranged opposite the other end of the optical fiber, a fixture fixed to an object to be protected from theft, an electrical circuit arranged within the fixture, mechanical connector means for mechanically connecting the flexible tying member to the fixture, and electrical connector means for electrically connecting the light emission element and the light receiving element to the electrical circuit. The electrical circuit is responsive to a change in a photo signal generated by the light emission element and transmitted through the optical fiber, for performing a warning function.

Abstract: An intake valve apparatus for an air pump having a cylinder with a cylinder iner, a piston positioned within the cylinder liner, a cylinder head and an intake valve. The intake valve comprises an upper annular valve plate having a reed extending inwardly therein and a lower seat plate having an opening facing the reed, the valve plate and seat plate being held between mating surfaces of the cylinder liner and the cylinder head and wherein the reed is positioned for movement in the seat place.

Abstract: A flexible tying member for a theftproof device which is adapted to give warning in response to a change in a photo signal transmitted in an optical fiber extending through the flexible tying member. The flexible tying member has a first layer including the optical fiber and at least one electric wire connected to at least one optoelectric element, and a second layer including a reinforcing member. The flexible tying member has a coaxial structure having an inner layer formed by the above first layer, and an outer layer formed by the above second layer, or a parallel structure in which the above first and second layers longitudinally extend parallel with each other.

Abstract: An air pump apparatus having a cylinder extending from a pump casing. The cylinder comprises a cylinder liner positioned within the walls of the cylinder and a piston is mounted for reciprocating movement within the cylinder liner. The pump chamber is formed between the front of the piston and the front portion of the cylinder wherein an annular gap is formed between the piston and the inner wall of the cylinder liner, wherein the piston has a plurality of annular grooves formed on the outer circumferential surface thereof, the annular gap and annular grooves forming a labyrinth path extending from the pump chamber.

Abstract: A speedometer of a centrifugal force type member employing weight members which are rotatable with a shaft for transmission to a thrust member. Displacement of the thrust member takes place and carries a pointer to move with respect to a scale.

Abstract: An apparatus for warning that a key-operated device in a vehicle is inoperative. The vehicle is provided with a warning buzzer connected in series with one or more door switches that are closed by opening a door. A vibrating member of the buzzer is so arranged that the same is restrained by a control pin which is moved with the key-operated device provided on the vehicle. Additional, optional features of the apparatus are also disclosed.