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:
Oct. 27, 1992
Filed:
May. 30, 1991
Claus Kramer, Besigheim, DE;
Bernd Taubitz, Schwieberdingen, DE;
Karl-Heinz Haegele, Vaihingen.Enz, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A vibration motor having a disk-shaped stator containing a piezoelectric excitation system, a disk-shaped rotor aligned parallel to the stator and mounted on a driven shaft in a manner fixed against relative rotation, and a pressing element that presses the rotor and stator together axially. To assure free travel of the driven shaft when the motor is currentless, the pressing element is embodied as a force-transmitting element that changes shape as a function of temperature, for instance a compression spring of memory metal. In motor operation, the element is kept at a temperature above its temperature point for the shape change, and it is disposed such that the pressing force between the rotor and stator diminishes as a result of the shape change ensuing if the temperature drops below this temperature point.