Mitsubishi Electric Corporation

Hiroshi Nagata

Toshikazu Satone

Hajime Nakajima

Takashi Okamuro

Masanori Nimura

Yoichi Omura

An encoder includes a first multiple rotation counter that generates first multiple rotation data using a rotation signal indicating one rotation of a rotational shaft of a motor, a second multiple rotation counter that generates second multiple rotation data using the rotation signal, a first cumulative-number calculation unit that calculates first accumulated multiple rotation data using an angle signal indicating a rotational angle of the rotational shaft, a second cumulative-number calculation unit that calculates second accumulated multiple rotation data using the angle signal, and a first comparative diagnosis unit that diagnoses whether the encoder has a fault by performing a comparison to determine whether the first multiple rotation data, the second multiple rotation data, the first accumulated multiple rotation data, and the second accumulated multiple rotation data are a same value.

Servomotor and encoder

A rotary encoder includes a rotary encoding unit attached to a rotary shaft which is rotatably held in a metal casing, a number-of-revolution detection unit supported by the metal casing for detecting a number of revolutions of the rotary encoding unit and producing heat, a cylindrical insulating resin cover having a base end attached to the metal casing for accommodating therein the rotary encoding unit and the number-of-revolution detection unit, a metal lid for blocking an opening of the other end of the insulating resin cover, and a shield cable electrically connected to the number-of-revolution detection unit and drawn out from a cable outlet of the metal lid. A shield of the shield cable is heat-transferably and electrically connected to the metal lid.

Growing community of inventors

Chiyoda-ku, Japan

Hiroshi Nagata