Fujitsu Fanuc Limited

Fanuc Corporation

Shigeki Kawada

Hiroshi Ishida

Masatoyo Sogabe

Yoichi Amemiya

Yoshiki Fujioka

Noboru Iwamatsu

Shigeaki Oyama

Naoto Ohta

Mitsuhiko Hirota

Yutaka Koiwai

Yoshinori Kohzai

Katsuo Kobari

Hidetsugu Komiya

Hideaki Oku

Shinichi Kouno

Yo Ikebe

Yoshihiro Hashimoto

Jiro Nakano

Takeshi Nakamura

Keiji Sakamoto

Kazushi Kumagai

Keiichi Harano

Kousei Nakamura

Katsuo Kohari

Toyohiko Nishimori

Sakae Yamamura

Katsuya Sugahara

Yasuo Takahasi

Speed control of an induction motor is effected in digital fashion through use of a computer but without complex processing, and with a computer that need not be large in scale. This is accomplished by processing at least a speed command signal, actual speed signal and torque signal in analog fashion, enabling simplification of an induction motor speed control digital processing section which performs all other control operations in a digital manner. In a speed control network having a closed loop, a frequency-to-voltage converter, adder-subtractor, proportional integrator, polarity determining circuit absolute value circuit and voltage-to-frequency converter are constructed of circuitry operable on the basis of analog values, with all other circuits being constructed of circuitry operable on the basis of digital values.

Induction motor control system

Method for drivingly controlling a variable reluctance type 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

Permanent-magnet field synchronous motor

Synchronous machine

Shaft for an electric motor with DC brake

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

Mechanism and method for automatically changing tools

A rotor structure comprising a shaft and a magnetic pole assembly comprising radially disposed permanent magnets and yokes. The magnetic pole assembly is supported by the shaft through end plates. The end plate has a recess to receive the end of the magnetic pole assembly. The magnetic pole assembly can be fit into the end plates.

Permanant magnet field type rotor structure for an electric machine

Stator of motor

System for detecting rotational speed

Welded stator using non-magnetic bars in specially shaped lamination

Growing community of inventors

Hino, Japan

Shigeki Kawada