Shicoh Engineering Co., Ltd.

Hitachi Metals, Ltd.

Kanegafuchi Chemical Industry Co., Ltd.

Hitachi Metals & Shicoh Engine

Osami Miyao

Manabu Shiraki

Masayuki Ohsaka

Kazuo Suzuki

Yasunobu Hiratsuka

Masayuki Fujiwara

Kikuo Shimazu

Shoji Fujisawa

Daishi Yamaguchi

Shunji Kawashima

Soota Komiya

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.

Flat vibration generating apparatus

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.

Linear direct current motor

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. The A phase magnetoresistive element member extends over ##EQU2## and the B phase magnetoresistive element member is out of phase with the A phase magnetoresistive element member by ##EQU3##

Magnetic encoder using magnetoresistive element

A moving-magnet type linear d.c. brushless motor having plural moving elements on a traveling track, and including a stator armature on the traveling track; n moving elements, each including a thrust-generating field magnet having P contiguous magnetic poles of alternating N and S polarity, where n is an integer greater than 1 and P is an integer of at least 1, the moving elements having one side facing the stator armature and traveling separately and independently along the traveling track; a plurality of position-detecting magnets, each corresponding to a different one of the moving elements and having P magnetic poles of N and S polarity at in-phase positions of substantially the same pitch relative to the poles of the thrust-generating magnets; and position detecting means including a group of position sensors corresponding to each position-detecting magnet for generating an electric current in the stator armature to move the moving elements in predetermined directions separately and independently, each position sensor detecting the magnet poles of only the corresponding position-detecting magnet.

Moving-magnet type linear d.c. brushless motor having plural moving

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.

1-Phase energized disk-type brushless motor

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.

Laser scanning motor having a rotating polygonal mirror and method of

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.

Unidirectional brushless motor

1-phase energized disk-type brushless motor

A single-phase brushless motor which can rotate smoothly by a uniform torque over an entire range of rotation with reduced torque ripples, without generating a high cogging torque for allowing self-starting of the motor. The motor comprises a field magnet as a rotor having 2P north and south magnetic poles, either the north or the south poles having a width equal to an electrical angle of about 120 degrees while the other poles have a width equal to an electrical of about 240 degrees. The field magnet is mounted for rotation in an opposing relationship to a stator armature core which has a plurality of radially extending stator poles formed in a circumferentially equidistantly spaced relationship thereon. A plurality of stator coils for two phases are wound selectively on the stator poles. An electric circuit detects the position of the field magnet to energize the armature coils for the two phases alternately for an electric angle of about 180 degrees.

Single-phase brushless motor with cogging features

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.

Single phase brushless motor with a core

A 1-phase coreless disk-type brushless motor or axial-flow brushless fan motor comprises a single position-detecting element located at a position on a printed circuit board corresponding to one of the magnetically active conductor portions of a stator coil or coils of the stator armature. A cogging-generating stator yoke having a cutaway portion of a specifically determined angular width is positioned relative to the stator coils, such that an end of the cutaway portion thereof is spaced by a distance equal to about one fourth of the pole width from another magnetically active conductor portion of the stator coils, so that the magnet rotor may stop at a position from which the motor can start itself. Various forms of such cogging generating stator yoke are disclosed, including a stator yoke which also serves as a circuit board.

1-Phase self-starting disk-type brushless motor with cogging-producing

A 1-phase brushless motor comprises a single position-detecting element located at a stationary position corresponding to a magnetically active conductor portion of an armature coil of an armature member. The position-detecting element is either a magnetoelectric transducer or a position-detecting coil. A plastics magnet is molded integrally with the armature coil and is magnetized such that it cooperates with a field magnet as a rotor to generate a field magnet attracting and repulsing torque within a particular range from a dead point, so as to stop the field magnet at a position from which the motor can start itself.

1-phase self-starting brushless motor

A 1-phase coreless disk-type brushless motor comprises a single position-detecting element located at a stationary position corresponding to a magnetically active conductor portion of an armature coil or coils on a stator yoke. A cogging-generating magnetic element having a width substantially equal to the width of each pole of a field magnet is located such that the center radial line between the width thereof is spaced by a distance equal to about three fourths of the pole width from another magnetically active conductor portion of the armature coil or coils so that the magnet rotor may stop at a position from which the motor can start itself.

1-phase self starting disk-type brushless motor with cogging element

A 1-phase disk-type brushless motor comprises a cogging-generating magnetic member or plate having a width substantially equal to the width of each pole of a magnet rotor and located at a specific position on a stationary printed circuit board so that the magnet rotor may stop with one pole thereof just opposed to the magnetic member, thereby assuring self-starting of the motor. The cogging generating magnetic member is shaped such that the volume or area may gradually decrease forwardly relative to the direction of rotation of the motor so that the cogging torque generated by the magnetic member may gradually increase upon starting of the motor, thereby assuring smooth rotation of the motor.

A single-phase brushless motor which can rotate smoothly with minimized torque ripples without generating a cogging torque. A magnet rotor of the motor has north and south magnetic pole and non-magnetized zones successively formed in ranges thereof each having an angular width of 120 degrees in electrical angle, and a stator armature is mounted in an opposing relationship to the magnet rotor and includes an annular stator yoke on which a same number of stator coils for each of 3 phases are wound in a troidal configuration and successively located in an angularly spaced relationship by an electrical angle of 120 degrees. A position detecting element is located for detecting a magnetic pole or non-magnetized portion of the magnet rotor, and in response to signals successively developed from the position detecting element during rotation of the magnet rotor, an energization controlling circuit successively energizes the stator coils to rotate the magnet rotor in a predetermined direction.

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Sagamihara, Japan

Osami Miyao