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:
Sep. 12, 1978
Filed:
May. 16, 1977
Graham Wilson McLean, Lymm, GB;
David Holt, Stapleford, GB;
Strathearn Audio Limited, Belfast, GB;
Abstract
An electric motor, particularly for driving a gramophone, a tape recorder or an electric instrument at a low rotational speed whereby an induction effect is utilized to achieve good starting torque and a reluctance effect to give good torque when the motor is locked in and running synchronously. The motor includes a stator assembly with a first plurality of pairs of primary pole pieces each pair constituted by a first metal part for the energization by an in-phase current and a second plurality of pairs of primary pole pieces each pair constituted by a second metal part for energization by an out of phase current. The respective parts also define slots constituting secondary pole pieces. A rotor assembly defines a plurality of further pole pieces having a pitch corresponding to the pitch of the secondary pieces, so that when the secondary pieces associated with the first plurality are opposite to the respective ones of the further pole pieces the secondary pole pieces associated with the second plurality of pieces are displaced with respect to respective ones of the further pole pieces by the phase angle between in-phase and out-of-phase currents.