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:
May. 09, 2006
Filed:
Feb. 13, 2002
Reiner Bindig, Bindlach, DE;
Jürgen Schmidt, Marktredwitz, DE;
Matthias Simmerl, Herrfenfeld, DE;
Günter Helke, Lauf, DE;
Hans-jürgen Schreiner, Neunkirchen am Sand-Rollhofen, DE;
Reiner Bindig, Bindlach, DE;
Jürgen Schmidt, Marktredwitz, DE;
Matthias Simmerl, Herrfenfeld, DE;
Günter Helke, Lauf, DE;
Hans-Jürgen Schreiner, Neunkirchen am Sand-Rollhofen, DE;
CeramTec Ag Innovative Ceramic Engineering, Plochingen, DE;
Abstract
In piezoceramic multilayer actuators, the head region and the foot region consist of inactive, that is to say electrode-free, piezoceramic layers. Due to the arrangement of the metallic electrodes and the layers of the piezoceramic materials, the shrinkage of the piezoceramic material, in particular in the passive head region and foot region, is influenced during the sintering process and can cause the formation of cracks. Different expansion behavior of the active and of the passive region during operation also lead to stresses which favor crack formation, in particular at the boundary between both regions. According to the invention, it is therefore proposed that a transition region (), whose shrinkage and expansion behavior lies between the shrinkage and expansion behavior of the active region () and the shrinkage and expansion behavior of an inactive region () which are electrode free, adjoins the active region () up to the inactive head region () and up to the inactive foot region ().