Abstract: A zoom lens apparatus which is superior in sound insulating and dust-proof properties and is easy to handle in transportation, storage and so forth. A lens system including a zoom lens set, a focusing lens set and an iris disposed on a single optic axis, a zoom lens driving section composed of a motor, a ball screw, a lens holding member, a nut member and so forth for driving the zoom lens, a focusing lens driving section composed of a guide rod, a lens holding member, a movable coil, an outer yoke, magnets and so forth for driving the focusing lens, and an iris motor for opening and closing the iris are accommodated in the housing having a substantially rectangular outer profile.

Abstract: A camera lens barrel having a first grouped lens, a movable second grouped lens for variable magnification, a third grouped lens, and a fourth grouped lens, which are respectively arranged along an optical axis, and accommodating a drive system for the first to fourth lenses. The camera lens barrel is provided with a stepping motor, a control device capable of respectively carrying out in a low speed drive mode at least micro step drive control and pulse drive control of the stepping motor, and a moving mechanism for converting rotation of the stepping motor into movement of the second grouped lens along the optical axis. The control device carries out position control of the second grouped lens according to a control quantity of the stepping motor. As the stepping motor is driven under the micro step drive control, the generation of noise and vibration can be greatly suppressed as compared with a conventional lens barrel employing a DC motor as a drive source.

Abstract: A position detecting apparatus comprising a magnet secured to a movable body (lens holder) which is movable along a shaft body when the shaft body is inserted, the magnet having polarity which is alternately magnetized at a predetermined interval, and a magneto-resistance effect element which is positioned and fixed so as to be confronted to the magnet at a predetermined gap interval by an MR holder with the shaft body being used as a securing position reference, and the magneto-resistance effect element serving to obtain a position detection signal for the movable body through variation of a resistance value thereof which is caused by magnetic field of the magnet through movement of the movable body.

Abstract: A camera lens barrel having a housing which includes front and rear housing members. The lens barrel also includes driving power sources mounted within the lens barrel housing, and reference shafts which are supported in the lens barrel housing and extend parallel to an optical axis of the lens barrel. Further, a plurality of lens groups which include one group for zooming and another group for focusing, are mounted within the lens barrel housing. The lens groups for zooming and focusing are retained by separate lens holders which are mounted to the reference shafts so as to be reciprocally movable along the reference shafts upon activation of the driving power sources.

Abstract: In a velocity sensor having a coil and a stick-shaped magnet inserted into the coil and magnetized such that opposite magnetic poles are provided at opposite longitudinal ends thereof, the coil and the magnet being movable relatively, the coil is wound more at the ends than at the center thereof.

Abstract: A zoom lens apparatus which is superior in sound insulating and dust-proof properties and is easy to handle in transportation, storage and so forth. A lens system including a zoom lens set, a focusing lens set and an iris disposed on a single optic axis, a zoom lens driving section composed of a motor, a ball screw, a lens holding member, a nut member and so forth for driving the zoom lens, a focusing lens driving section composed of a guide rod, a lens holding member, a movable coil, an outer yoke, magnets and so forth for driving the focusing lens, and an iris motor for opening and closing the iris are accommodated in the housing having a substantially rectangular outer profile.

Abstract: A novel lens barrel which includes a comparatively small number of parts, has a comparatively low weight and can be produced at a comparatively low cost. The lens barrel apparatus comprises an outer shell, a lens holding member holding a focusing lens thereon and mounted in the outer shell for movement in a direction of an optic axis of the focusing lens, and an actuator including an actuating coil secured to one of the lens holding member and the outer shell and wound around a coil bobbin. The actuator further includes a magnet secured to the other of the lens holding member and the outer shell in a coaxial relationship with the actuating coil around the optic axis, and a detecting coil is wound on the coil bobbin in an overlapping relationship with the actuating coil for detecting a speed of movement of the focusing lens.

Abstract: A multilayer coil is formed from a single conductor wire having first (beginning) and second (terminating) lead wires, the conductor wire being first formed as a coil winding with a plurality of layers such that the coil winding has a thickness so as to form an outer peripheral wall, with the first lead wire extending from an inner portion of the coil winding and the second lead wire extending from the outer peripheral wall, and the first lead wire is then wound as an additional layer on the coil winding so that the free end of the first lead wire also extends from the outer peripheral wall.

Abstract: In manufacturing an electric motor commutator which includes a cylindrical insulator having an axial bore for receiving the shaft of an electric motor, and a plurality of segments of commutator metal, such as, copper, extending about the outer circumferential surface of the insulator and being spaced apart by axially extending slots opening radially outward from the insulator between confronting surfaces of adjacent segments; the circumferential surfaces of the segments are shielded, as by plating the same with a metal other than the commutator metal, such as, silver, nickel, tin or zinc, or by coating such circumferential surfaces with a paint, whereupon, the resulting commutator assembly is oxidized so that only the confronting surfaces of the segments between which the slots are defined are covered with insulating layers of copper oxide, and then the shielding, along with any oxide that may have been formed thereon, is removed from the circumferential surfaces of the segments for exposing the copper or oth