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:
Jun. 02, 1981
Filed:
Jan. 30, 1979
Manfred Nonnenmann, Schwieberdingen, DE;
Werner Hummel, Waiblingen, DE;
Suddeutsche Kuhlerfabrik Julius Fr. Behr GmbH & Co. KG, Stuttgart, DE;
Abstract
A fluid friction clutch, especially for driving the cooling fan of an internal combustion engine. The rotating clutch housing has a separating wall defining a fluid reservoir chamber and a drive chamber and the separating wall has a passage which is opened and closed by a valve. The valve is actuated by an electromagnet disposed substantially coaxially with the clutch. A permanent magnet is attached to the valve assembly coaxially with the electromagnet and of opposite polarity to the magnetic field polarity which occurs when the electromagnet is energized. Upon energization, the opposing magnetic fields repel the two magnets and cause the valve to close, thereby disengaging the clutch. When the electromagnetic is deenergized, a spring reopens the valve and permits full engagement of the clutch.