Fanuc Corporation

Fujitsu Fanuc Limited

Noboru Iwamatsu

Yoichi Amemiya

Shigeki Kawada

Masatoyo Sogabe

Yoshiki Fujioka

Hiroyuki Uchida

Yoshinori Kohzai

Tomonaga Yamamoto

Yoshiyuki Hayashi

Hideaki Oku

Yoshinori Kozai

Yuichi Endo

Syougo Higashi

Rotor for synchronous motor

Rotor of synchronous motor

Hollow shaft motor

Provided is a rotor structure by which slot ripple is reduced so that an a.c. synchronous servo motor can achieve a smooth rotation. A rotor structure is provided in which two rotor elements (30, 30') are juxtaposed and brought out of registration in a circular position by an angle (.theta.) corresponding to a half wave length of a slot ripple wave caused in a rotor having a prior structure, thereby each slot ripple wave caused by each rotor element (30, 30') is cancelled out by the other.

Rotor structures of A.C. synchronous servo motor

In an AC servomotor constructed so that the outer circumference (21b) of a stator core (21) formed by laminating thin steel plates (22) is used as part of a motor housing, bearing mounting bores (25a, 26a) for receiving bearing members (27, 28) to be mounted on a pair of brackets (25, 26) attached to the front and rear ends of the stator core (21) and mounting surfaces (25b, 25c) of the motor are formed with accurate concentricity and squareness with reference to the center bore (21a) and the outer circumference (21b) of the stator core (21) after firmly joining the brackets (25, 26) to the stator core (21). Thus, a rotor (29) is supported with high accuracy in concentricity with the stator core (21) on the brackets (25, 26) and the squareness of the output shaft (29a) to the mounting surfaces (25b, 25c) is established.

AC servomotor and a method of manufacturing the same

A rotor for a synchronous motor, having a plurality of first magnetic poles formed by a plurality of permanent magnets respectively and disposed at practically equal circumferential intervals on the outer circumference of a yoke fixed to a rotatable motor shaft, and a second magnetic pole projecting radially from the yoke adjacently to each first magnetic pole and the second magnetic pole wherein the shape of the pole face of each first magnetic poles are in a circular arc and the shape of the pole face of each of second magnetic pole is determined by a given equation so that the magnetic flux distribution established by a pair of the first magnetic pole and the second magnetic pole is substantially equivalent to a sinusoidal magnetic flux distribution in the sweeping effect by the armature coils of each phase of the stator.

Rotor for a synchronous motor

Synchronous machine

A permanent-magnet field rotor (10) includes a plurality of permanent magnets (18) disposed in a radial fashion, and yokes (19) disposed between each two successive permanent magnets (18) and made of a lot of sheet elements (20). The method of manufacturing the permanent-magnet field rotor comprises the step of stacking a lot of same shaped thin plate members (25) each having a plurality of sectoral york element portions (26) arranged in a radial fashion and link portions (27) each linking the outer circumferential edges of each two successive york element portions (26) to one another so as to define therebetween a permanent magnet receiving slot (29). In the state where permanent magnets (18) are inserted in the slots (29) of the stacked thin plate members (25), respectively, the stacked thin plate members (25) are firmly fixed to each other. Each of the link portions (27) of the stacked thin plate members (25) is cut out in the stacking direction by a range which is less than the width of each permanent magnet (18). From this, the yokes (19) made of sheet elements (20) are formed at the opposite sides of each permanent magnet (18) and separated from one another.

Method of manufacturing a permanent-magnet field rotor

Synchronous rotary machine

Stator of motor

Non-contacting, speed-detecting device of a direct-current generator type

A tachometer generator comprising a generator section for producing rectangular polyphase alternating voltages having a peak value which is proportional to the speed of the rotor, and a commutator section including contactless change-over switches for successively transferring the alternating voltages from the generator section, and sensors for producing switching signals which actuate the change-over switches in accordance with the rotational position of the rotor of the generator section. In the commutator section the sensors are equivalent in number to the change-over switches and comprise Hall devices arrayed about a rotary shaft which is coupled to the generator section. The alternating voltages which are obtained successively from the coils of the generator section as the rotary shaft rotates, are transferred in order by the change-over switches to produce a speed signal, in analog form; which is proportional to the rotating speed of the rotor. The axially extending width of the rotor is smaller than the axially extending width of the stator, the width of the rotor being approximately 80% that of the stator. A magnetic shield plate is interposed between the generator section and the sensors of the commutator section. The tachometer generator having the above arrangement generates more accurate speed signals and can be reduced in size since the generator and commutator sections are capable of being disposed closer together as a result of the provision of the magnetic shield.

Brushless tachometer generator

Growing community of inventors

Hino, Japan

Noboru Iwamatsu