Sumitomo Heavy Industries, Ltd.

Tohoku Techno Arch Co., Ltd.

Kennichi Makino

Yoshiyuki Tomita

Junichi Okada

Takumi Itoh

Satoshi Kiyono

Toru Hirata

Wei Gao

Yoji Watanabe

A motor drive apparatus of an electric forklift includes first and second torque command value generation units that individually generate a torque command value indicating torque of a corresponding traveling motor in response to a gap between a speed command value and a speed detection value; and first and second slip detectors that individually generate a slip ratio estimation value showing a slip state of a corresponding drive wheel based on the speed detection value and the torque command value. The slip detectors individually have a first arithmetic unit which generates an inertial force estimation value proportional to a differential value of the speed detection value of the corresponding traveling motor and a second arithmetic unit which generates the slip ratio estimation value in response to a relationship between the corresponding inertial force estimation value and the torque command value of the corresponding traveling motor.

Motor drive apparatus for electric forklift and electric forklift adopting the same

According to one aspect of the invention, there is provided a sensor device which is capable of detecting a state of a movable stage using an easily manufacturable reference grating and capable of improving the accuracy of detection. The sensor device comprises a reference grating which has a configuration that is varied periodically in a two-dimensional direction. A light source emits light to the reference grating. A spectral unit has a plurality of openings to convert the light emitted by the light source into a plurality of light beams through the plurality of openings. A detector unit has a photodetector to receive collectively reflected light beams reflected by the reference grating. The detector unit is provided to detect a state of a movable body relative to the reference grating based on a change of the reflected light beams received by the photodetector.

Sensor device and stage device

A position control device of a moving body, by which position control device a moving body can be driven in a translational manner with high precision where the moving body is not rotated in a yawing direction even if disturbance is input, a stage device using the position control device, and a position control method of a moving body, is provided.

Position control device of moving body, stage device using the position control device, and position control method of moving body

Growing community of inventors

Hiratsuka, Japan

Kennichi Makino