Aisin Seiki Kabushiki Kaisha

Kohki Ohara

Masanori Sugiyama

Koichi Hirota

Daisuke Yamada

Chiaki Honma

Kazuyoshi Mori

Shinichiroh Iwasaki

An energization control device is provided to prevent rapid decrease of current which is flowing through each of phase coils of an electric motor. A time duration is divided into three stages which ranges from an initiation of the current supply to the phase coil to a termination of the current supply to the phase coil. At the first stage, the second stage, and the third stage, soft/hard chopping energization control, 0-volt energization, and duty chopping energization control, respectively, are made. Energizing the phase coil is made by way of a first switching element and a second switching element. At the first stage, depending on an actual current value being in excess of a target current value, either of or both of the first switching element and the second element are made OFF. At the second stage, while the second switching element is being made OFF, the second switching element is made ON. At third stage, while the second switching element is being made OFF, the first switching element is, at a duty cycle, made ON and OFF alternately in repetition.

Energization control device for electric motors

A rain drop detecting device includes an oscillation element disposed on a plate member such as a windshield for generating an ultrasonic wave on the plate member, an ultrasonic wave receiving element disposed on the plate member for receiving the ultrasonic wave generated by the oscillation element, a detecting device connected to the ultrasonic wave receiving element for detecting an amplitude of the ultrasonic wave, and an ultrasonic wave absorbing member disposed on the plate member. The absorbing member is designed to absorb a portion of the ultrasonic wave generated by the oscillation element to prevent the downwardly travelling portion of the ultrasonic wave from travelling beyond a desired region of the plate member. In the case of a windshield, the absorbing member can be used to prevent the ultrasonic wave from travelling to the resting location of the wiper so that inadvertent rain drop detection does not occur.

Rain drop detecting device

Growing community of inventors

Aichi-ken, Japan

Kohki Ohara