Abstract: A lens drive device having a simple structure and small sized. The lens drive device (1) has a lens holder (3, 5), a drive shaft (21) into which one end of the lens holder (3, 5) is fitted and placed along the direction of the optical axis of lenses (14, 16), and a piezo element (17) provided at a base end (21a) of the drive shaft (21). The base end (21a) of the drive shaft (21) is fixed to a vibrator (19) of the piezo element (17), and the drive shaft (21) is vibrated in the direction of its axis by vibration of the vibrator (19) produced by conducting a pulse current to the piezo element (17). The lens holder (3, 5) is moved in the optical axis direction by using repetition of inertia force and friction force of the holder relative to the drive shaft (21).

Abstract: A lens driving apparatus 1 of the present invention includes a substantially cylindrical yoke 3; a base 5 to which the yoke 3 is attached; a carrier 7 having a lens; a coil 10; and a magnet 13, wherein the carrier 7 is moved in a direction of an optical axis of a lens by electromagnetic force generated by passing current through the coil 10, the base 5 is substantially square-shaped as viewed from a plane, the yoke 3 is placed at an inner position of the base 5, the yoke 3 has an outer peripheral wall 3a and an annular inner peripheral wall 3b to be spaced to each other, each magnet is placed between the outer peripheral wall and the inner peripheral wall and at a position corresponding to a base corner portion of the base 5, and a space between the outer peripheral wall 3a and the inner peripheral wall 3b positioned at a base side portion 3e is made narrower than a space between the outer peripheral wall 3a and the inner peripheral wall 3b positioned at the base corner portion.

Abstract: An optical structure is disposed on a surface of a device substrate, and a lens system for introducing external light into a solid-state image pickup device is placed in the center of the optical structure. The outer shape of the optical structure seen from the light incident side of the lens system is rectangular, and its plane shape forms a rectangular frame section. An intermediate structure is disposed between the device substrate and the optical structure. The intermediate structure has a fitting section for fitting the optical structure in a part of side faces of the frame section.

Abstract: A lens driving apparatus includes: a first yoke having an inner peripheral wall and an outer peripheral wall placed to be concentric with each other and forming a rectangular U-shape cross section and a cylindrical shape; a second yoke placed at an outer side of the first yoke to be concentric with the first yoke and forming a rectangular U-shape cross section and a cylindrical shape; a base; a first magnet and a first coil arranged in a rectangular U-shape interior of the first yoke; a second magnet and a second coil arranged in a rectangular U-shape interior of the second yoke; a first lens support member; and a second lens support member. The second lens support member is placed at an inner peripheral side of the second yoke and has the second coil fixed onto an outer periphery thereof. The first lens support member is linearly moved in a direction of an optical axis of a lens by an electromagnetic force caused by passing current through the first coil.

Abstract: A magnetic position detecting apparatus of the present invention includes a first magnetic resistance circuit and a second magnetic resistance circuit each having multiple magnetic resistance elements arranged to be opposite to a magnetized surface, wherein the first and the second magnetic resistance circuits are arranged in such a way that the resistance elements of the first and the second magnetic resistance circuits are connected to one another in series and arranged in a comblike shape to be parallel to one another along a current path of each magnetic resistance element, the magnetic resistance elements of the second magnetic resistance circuit are placed between the magnetic resistance elements of the first magnetic resistance circuit.

Abstract: In a position detecting apparatus 1 of the present invention, magnetic resistance circuits A and B of a first main circuit 10 include a reference magnetic resistance element +A, an even harmonic correction magnetic resistance element +A3, being placed at a position shifted by (1/4)? or (3/4)? from the reference magnetic resistance element +A, with respect to a reference wave, and a third harmonic correction magnetic resistance element +A2, being placed at a position shifted by (1/6)? from the reference magnetic resistance element, with respect to a reference wave, and magnetic resistance circuits A? and B? of a second main circuit 20 include the magnetic resistance circuit of the second main circuit 20 includes a reference magnetic resistance element +A?1, a fifth harmonic correction magnetic resistance element +A?2, being placed at a position shifted by (1/10)? from the adjacent magnetic resistance element, with respect to a reference wave and a fifth harmonic correction magnetic resistance element +A?2, bei

Abstract: An electromagnetic actuator comprises: a magnet; a pole piece mounted to the magnet; a yoke facing the pole piece; a coil base having a vibration coil; leaf springs for supporting the coil base and a weight; a case for enclosing them; a cover for covering one side of the case; and a diaphragm having a voice coil, wherein the arms of the coil base are inserted through notches formed in the yoke, and the vibration coil and the voice coil is disposed in a gap in which the pole piece and the yoke face each other. The weight vibrates by the application of a low-frequency current to the vibration coil, and the diaphragm vibrates by the application of a high-frequency current to the voice coil.

Abstract: An electromagnetic actuator comprises: a magnet; a pole piece mounted to the magnet; a yoke facing the pole piece; a coil base having a vibration coil; leaf springs for supporting the coil base and a weight; a case for enclosing them; a cover for covering one side of the case; and a diaphragm having a voice coil, wherein the arms of the coil base are inserted through notches formed in the yoke, and the vibration coil and the voice coil is disposed in a gap in which the pole piece and the yoke face each other. The weight vibrates by the application of a low-frequency current to the vibration coil, and the diaphragm vibrates by the application of a high-frequency current to the voice coil.

Abstract: A flat vibration generating apparatus wherein a flat coreless eccentric vibrator armature generates an eccentric vibration desired from the aspect of body feel. An air-core armature coil group thereof consists of m pieces (where m is an integer of 3 or more) of armature coils disposed in superposition with one another in m phases in an arrangement such that they are eccentric and with their phases deviated in a circumferential direction, and that they do not describe a complete disc-like shape as viewed from the axial direction.

Abstract: Disclosed herein is a linear d.c. motor comprising a field magnet composed of plural magnetic poles, and an armature formed by arranging armature coils along the moving direction of a moving element at a position facing the field magnet. One of the field magnet and armature is attached to the moving element, and the other is provided on a stator yoke serving as a stator. Projecting edges for linear guide, each of which projects outside and has a triangular form in cross section, are provided on both sides of the stator yoke, and guide rollers, each of which has an engaging groove in the form of a valley in its side part coming into slidable contact with the projecting edge for linear guide, are attached to the moving element. There is no possibility that the moving element is derailed because it is supported by the projecting edges of linear guide and the guide rollers. It is therefore possible to make the thrust of the moving element greater and cause it to travel at high speed.

Abstract: Disclosed herein is a swing-arm type linear d.c. brushless motor, wherein at least one coreless type armature coil such as an air-core armature coil is arranged on the inner wall of a linear motor body and a field magnet is formed by magnetizing a magnet member with a single pair of N/S poles so as to permit the generation of thrust in a predetermined direction face to face with only one active conductor of said at least one armature coil and which does not contribute to the generation of reverse thrust. The field magnet is opposite through an air-gap in the axial direction to only the active conductor portion, and is supported relatively and swingably through the air-gap. It is suitable for use in small, economical and high-speed magnetic head positioner mechanisms more useful in small-capacity magnetic disk units and the like and capable of performing position detecting, feed control, etc.

Abstract: An magnetic encoder includes a multipolar magnetic body having a row of alternate North and South poles of equal widths, and a magnetoresistive element diposed in confrontation to the multipolar magnetic body. The magnetoresistive element includes at least one A phase magnetoresistive element member and at least one B phase magnetoresisitve element disposed in juxtaposition over ##EQU1## where n is an integer greater than or equal to 1, and .lambda. is a width of each individual pole of the multiplar magnetic body. Each of the A phase magnetoresistive element members and the B phase magnetoresistive element member has a group of series connected linear conductors arranged side-by-side into a comb-like shape.

Abstract: A disk-type single-phase brushless motor wherein a reluctance torque having a sufficient magnitude can be generated to assure self-starting and continued rotation of the motor and production of disagreeable noises is minimized. The motor comprises a stator yoke mounted in an opposing relationship to a magnet rotor with an axial air gap left therebetween. The magnet rotor has an equal circumferential pole width .theta.. The stator yoke has a cutaway portion formed therein for enabling self-starting of the motor. The cutaway portion has a specific shape including a first radially extending edge and a second edge extending in a predetermined angular relationship from an inner end of the first edge to an outer circumferential edge of the stator yoke.

Abstract: A disk-type brushless fan motor comprises a stator yoke having a suitable cutaway portion formed therein for allowing generation of a cogging torque to allow self-starting of a magnet rotor of the motor. A printed circuit board underlies the stator yoke, and a position detecting element is located on a face of the printed circuit board opposing to the cutaway portion of the stator yoke. The printed circuit board has one or more small cutaway portions formed along an outer periphery thereof within a range of the cutaway portion of the stator yoke, and opposite leads or terminals of a pair of armature coils located on the stator yoke extend through the cutaway portions of the printed circuit board in order to establish electric connection to electric parts located on the rear side of the printed circuit board.

Abstract: A 5-phase dc motor which can be mass-produced readily at a reduced cost. The motor comprises a field magnet having four alternate north and south magnetic poles of an equal angular width, a rotor including a rotor armature core having five rotor pole shoes formed in an angularly equidistantly spaced relationship by an electrical angle of 144 degrees, a commutator including ten commutator segments provided successively on the rotor, and a pair of brushes disposed in a spaced relationship by an angular distance of 180.degree. electrical and for sliding contact with the commutator. A single conductor is electrically connected to the commutator segments and wound on the rotor pole shoes in a predetermined specific sequence to form armature windings which do not overlap with any other armature windings.

Abstract: A light-weighted, inexpensive axial-flow fan apparatus which can prevent axial leakage of a magnetic flux of a brushless motor installed therein. A body member of the apparatus or a motor casing on which the motor is supported is made of a non-magnetic material such as a resin material, and a name plate formed from a magnetic seal is applied to the bottom of the motor casing so as to pass a magnetic flux therethrough.

Abstract: A laser scanning motor includes a coreless flat brushless motor disposed in a rotatable polygonal mirror having polygonal outer mirror surfaces. A light beam applied to the polygonal mirror is deflected by controlling the rotation of the coreless flat brushless motor. Poles and a bearing holder of the coreless flat brushless motor in a rotor assembly are formed of a plastic magnetic material. When manufacturing the laser scanning motor, the poles and the bearing holder are formed simultaneously by filling the plastic magnetic material in one operation, and then firmly securing the poles and bearing holder to the rotor assembly.

Abstract: An inexpensive brushless motor including a single position detecting element can start itself and can rotate smoothly with good efficiency and reduced noise. The motor comprises a stator core having T-shaped radial stator poles with driving coils wound on all or some of the stator poles. A field magnet having driving alternate N and S magnetic pole zones is mounted for rotation in an opposing relationship to circumferential faces of the stator poles of the stator core. A cogging generating magnetic plate is located in an opposing relationship below the field magnet and has a cutaway portion formed therein which has a suitable angular width such that the magnetic plate may generate a cogging, to move the field magnet by attraction therebetween to a position other than any dead point, and from which the field magnet can start itself. The single position-detecting element is located such that it may detect no dead point upon starting of the motor.

Abstract: A 1-phase energized disk-type brushless motor or fan motor comprises a single position detecting element located at a position on a printed circuit board corresponding to one of magnetically active conductor portions of one of stator coils of the stator armature. The magnetically active conductor portions include a width substantially equal to the width of each pole of the magnet rotor. A cogging generating magnetic member or plate having a width substantially equal to the pole width is located on the printed circuit board such that it is spaced by about three fourths of the pole width from one of the conductor portions of one of the stator coils so that the magnet rotor may stop with one pole thereof just opposed to the magnetic member, thereby assuring self-starting of the motor and uniform turning torque over the entire rotation of the motor.

Abstract: A cored single-phase brushless motor including a single position-detecting element can start itself without provision of a special cogging generating means. A field magnet as a rotor of the motor has alternate north and south magnetic pole zones, one of which has a width equal to an electrical angle of about 120 degrees while the other has a width equal to an electrical angle of about 240 degrees. A stator armature core has stator poles formed in a circumferentially equidistantly spaced relationship thereon and having a width equal to an electrical angle of about 120 degrees, and armature coils are wound on the stator poles. A position-detecting magnet rotor is formed on the field magnet, and a magnetic sensor detects a north, south magnetic pole or non-magnetized zone of the magnet rotor, to detect the position of the field magnet. An electric current successively energizes, in response to signals from the magnetic sensor, the armature coils for an electrical angle of 120 degrees to rotate the rotor.