Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Youichi Fujita

Sotsuo Miyoshi

Satoshi Kawamura

Toshihiko Miyake

Yuji Nakahara

Satoru Akutsu

Akira Hashimoto

Junji Kawada

Tadashi Hasegawa

Hiroshi Miyazaki

Yasunori Takai

Masaru Matsumoto

Masayuki Yokoyama

Kenta Hatano

Tomokuni Kato

Ken-ichi Azuma

Naohiro Oketani

Satoru Hasegawa

Katsunori Takai

Yoshitaka Ikitake

Kenichi Azuma

Osamu Yatsuki

A coil temperature estimation unitestimates the coil temperature of a motorfrom the equivalent resistance, heat capacity and thermal resistance of the coil of the motor, which are given in advance, from the applied voltage to the motordetected by a voltage detector, and from a duty ratio command value input from the outside. When a temperature abnormality deciding unitdecides that the coil temperature is not normal, a duty limiterlimits the duty ratio command value at a low value and outputs it to a FET driving circuit

Motor control device

A valve device has integrally assembled thereto a valve side housinghaving a valve seat, a motor side housingprovided with a motor, and a feeder-side housinghaving a feeder unit, wherein a valve stemprovided with a valvefor abutting against the valve seatis extended to the interior of the feeder-side housing, a rotation stopperof the valve stemis provided at a predetermined position of the valve stem on its way to the feeder-side housing, a screw sectionis provided around the portion of the valve stem passing through the center holeof the rotorof the motor, the screw section being in mesh with a thread sectionformed around the surface of the center hole thereof, and a valve position detecting sensor is provided within the feeder-side housing

Valve device

A direct current motor includes: a stator () on which a plurality of coils () is provided; a rotor () including a plurality of permanent magnet magnetic poles () that is provided so as to face an inner periphery of the stator, and a pipe () on one end; a current-carrying portion () that is provided on the other end of the rotor () and commutates current supplied from a power source to the coils () on the stator (); a sleeve bearing () that holds the rotor (); and a ball bearing () that holds the rotor () and has a larger load-bearing capacity than that of the sleeve bearing (). Furthermore, the pipe () holds the ball bearing () and is in direct contact with the ball bearing ().

Direct current motor

To provide a DC motor in which the rattling and the axial deviation of a rotor are restrained without increasing the axial dimension of the motor. This DC motor comprises a stator () on which coils () are provided, a rotor () so disposed as to be opposed to the inner periphery of the stator () and having magnetic poles, a current-carrying part provided at one end of the rotor () and transferring the current fed from a power supply to the coils () of the stator (), a sleeve bearing () holding the rotor (), and a ball bearing () holding the rotor () and having a load-carrying capacity larger than that of the sleeve bearing (). The outer ring of the ball bearing () is positioned by the stator (), and the inner ring of the ball bearing () is positioned by the rotor ().

Direct-current motor

In a DC-motor according to the present invention, contact areas of first brushes can be enlarged without enlarging the external diameter of a disk on which a commutator is provided; therefore, the wear resistance of the first brushes can be enhanced while maintaining a good control-response; and at the same time, the axial dimension can be shortened dramatically, so that the DC-motor can be downsized. The first brushesare radially in contact with the commutator, and second brushesare axially in contact with slip ringsthat are formed circumferentially inside the commutator

DC-motor

Output shaft coupling structure of electrically operated control valve including: valve rod which is provided with valve for opening and closing fluid passage and is mounted to valve housing in such a way as to move along axial direction; and electrically controlled motor for driving the valve rod along the axial direction, the coupling structure couples motor shaft of the electrically controlled motor to the valve rod, and the plate shaped like a flat plate is fixed at its center to end portion, to which the valve rod is coupled, of the motor shaft and the plate is bent to form hooking and engaging portion at its both ends after the plate is fixed, thereby the plate hooks and engages with the valve rod.

Output shaft coupling structure of electrically operated control valve

A sliding hole is formed so that a screw portion can pass therethrough. Also, a seal member is provided at a portion, through which the screw portion placed in the sliding hole can pass and in which a sliding portion does not slide.

Motor which performs a rotational-to-linear motion conversion

Motor for rotational-to-linear conversion with shaft seal

Powder produced by abrasion due to sliding between a brush and a commutator is prevented from moving toward a rotor. A recess is provided between the rotor and a slide face of the brush and the commutator, where powder produced by abrasion at the brush may enter into a motor and increase sliding resistance of the rotor. Thus, there is no such powder produced by abrasion entering into the motor as increasing sliding resistance of the rotor.

Motor

A braking device of a DC motor has a position detecting means to detect a position of a motor shaft, a rotational speed detecting means to detect a rotational speed of the motor and a braking means to generate a braking force based on a position signal and a speed signal detected by both of the means, and stops the motor shaft quickly and smoothly without making the motor shaft collide with a stopper.

Brake for DC motor

One current passing circuit board is constituted by one metal plate in which a continuous current passing pattern that is to be separated in a plurality of current passing patterns is formed, and molded resin in which the metal plate is inserted. The current passing circuit board is pressed to eliminate the unnecessary portions of the above mentioned current patterns, thereby the one current passing circuit board is formed in a state where the current passing pattern continuously formed is separated in the normal forms.

Current passing circuit board for rotary electric machine inserted in molded resin

At the time of controlling a servo mechanism, a servo control detects that the position of a driven body is in the steady judgment region of a target position and varies a control constant (PI value) in the steady judgment region, so it is made possible to reduce an oscillation of the driven body in the steady judgment region.

Servo control device of DC motor

Particle trapping means for trapping worn particles of a commutator is provided in a power source side case mounted on a motor case of a DC motor.

Current passing device of EGR valve apparatus

When it is judged that a driven body reaches vicinity of a target position, a present phase of the passing current is not switched to keep a state of the passing current even if a phase of a passing current needs to be switched judging from the position of permanent magnet rotor thereby a stabilizing of torque can be attained.

Growing community of inventors

Tokyo, Japan

Youichi Fujita