The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 13, 1993
Filed:
Dec. 03, 1991
Kenji Yoshida, Tokyo, JP;
Akinobu Shionoya, Musashino, JP;
Kazuo Matsushita, Ohmiya, JP;
Isao Baba, Chino, JP;
Sinano Electric Co., Ltd., Tokyo, JP;
Mikasa Sangyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A concrete vibrator is disclosed in which a sensorless semiconductor motor is employed for driving an exciter. The sensorless semiconductor motor has an arrangement in which the rotational position of the permanent magnet rotor is sensed through utilization of a voltage which is induced from three-phase stator windings, i.e. a voltage which is induced according to the magnetic flux distribution in the gap and varies its frequency with the rotation speed alone instead of by using the Hall element which is readily damaged by vibration and heat, that is, seriously poor in environmental resistance. Further, the sensorless semiconductor motor is arranged so that the current supply to the stator winding is placed under control of a semiconductor inverter which is controlled by a PWM or PAM system.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile