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:
Mar. 02, 2004
Filed:
Jun. 21, 2002
Rudolf Heinz, Renningen, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
The invention relates to a piezoelectric actuator, in particular for actuating control valves or injection valves in motor vehicles, having an actuator body in the form of a multilayered laminate made up of stacked layers of piezoelectric material with intervening metallic or electrically conductive layers that function as electrodes, and the end faces of this actuator body are respectively contacted by a top plate oriented toward the valve having an axially protruding valve tappet and a bottom plate at the opposite end, wherein the actuator rests in an axial bore of a valve housing and is prestressed at the ends in the axial direction between the top plate and the bottom plate by means of a spring element. According to the invention, the actuator—at least including the top plate—is enclosed by an electrically insulating elastomer sleeve so that when installed, the actuator with the elastomer sleeve rests snugly against the inner wall of the axial bore of the valve housing in the vicinity of the actuator.