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. 30, 1997
Filed:
May. 31, 1995
Albertus J Van Der Borst, Drachten, NL;
Jan Tiesinga, Drachten, NL;
Jacobus N Dekker, Drachten, NL;
Ate K Damstra, Drachten, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A shaving apparatus (1, 101, 201) is provided which includes at least one cutting unit (11) which is provided with an external cutting member (13) with at least one hair trap opening (17) and with an internal cutting member (19) which is rotatable in the external cutting member (13) by means of an electric motor (23). The speed of the motor (23) can be controlled during operation by a feedforward control unit (43, 103, 203) as a function of at least one physical quantity which can be measured during operation by means of a transducer (59, 69, 111). A first embodiment of the shaving apparatus (1) comprises a timer (59) which measures a time which has elapsed during a shaving operation, and a detector (69) with a microphone (71) which measures a cutting frequency of the cutting unit (11), the speed of the motor (23) being controllable by the control unit (43) as a function of the time which has elapsed during the shaving operation and of the cutting frequency. A second embodiment of the shaving apparatus (101) comprises a force detector (111) which measures a skin contact force exerted on the cutting unit (11), and again a detector (69) with a microphone (71) measuring a cutting frequency of the cutting unit (11), so that the speed of the motor (23) can be controlled by the control unit (103) as a function of the skin contact force and the cutting frequency. In a special embodiment, the control unit (43, 103, 203) controls the speed of the motor (23) in accordance with an algorithm based on fuzzy logic. The shaving apparatus (1, 101, 201) provides a user of the shaving apparatus (1, 101, 201) with an optimum balance between shaving performance, shaving comfort and power consumption of the motor (23) during a shaving operation.