Patent assignee · CH · COMPANY

PORTESCAP

38Patents
0Active
38Granted
36Portfolio score

Filing activity: Sep 5, 1973 → Feb 29, 1996

Most-cited patents

PatentTitleAreaCited byStatus
US4658166A Synchronous electric motor with disc-shaped permanent magnet rotor Electricity 52 Expired
US4682067A Synchronous electric motor having a disc-shaped permanent magnet rotor Electricity 30 Expired
US5763874A Incremental optical encoder having partially opaqued quadrature detectors Physics 29 Expired
US4323805A Direct current micromotor Electricity 19 Expired
US4517478A Electric stepper motor Electricity 17 Expired
US4629916A Method and apparatus for harmonics suppression in motor systems Electricity 14 Expired
US4823040A Single-stage, two-phase of four-phase synchronous electric motor Electricity 13 Expired
US4714854A Electric motor with a multipolar permanent magnet rotor Electricity 13 Expired
US4518883A Electric motor with permanent magnet rotor Electricity 12 Expired
US4208868A Control device for a step-by-step motor Physics 11 Expired
US5053667A Di- or polyphase synchronous electric motor with a disc-shaped rotor Electricity 10 Expired
US4415845A Electric motor control device Physics 9 Expired
US4737753A Multipolar magnetization device Electricity 9 Expired
US4866323A Synchronous electric motor with magnetised rotor and method of manufacturing this motor Emerging Cross-Sectional Technologies 8 Expired
US4155018A Multipolar step motor Electricity 8 Expired
US4891538A Synchronous motor with sinusodial torque variation in each phase Electricity 7 Expired
US4082970A Direct-current motor-generator Electricity 7 Expired
US4242623A Miniature electric stepping motor Physics 6 Expired
US4219825A Electric actuating device Physics 6 Expired
US4387312A Stepping polyphased motor for a clockwork mechanism Electricity 6 Expired
US4136294A Direct-current micromotor Electricity 6 Expired
US4083222A Apparatus for measuring the rate of a watch Electricity 6 Expired
US4791331A Brush assembly for electric commutator motors Electricity 6 Expired
US4516064A Stepper motor control device Physics 5 Expired
US4060746A Electric direct current rotating machine Electricity 5 Expired

Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.