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. 29, 2004
Filed:
Sep. 17, 2002
Woo Sok Chang, Lexington, MA (US);
Thomas A. Keim, Boxborough, MA (US);
John G. Kassakian, Newton, MA (US);
Massachusetts Institute of Technology, Cambridge, MA (US);
Abstract
The present invention provides a means to reduce holding current and driving current of EMVD's effectively and practically and to provide soft landing of a valve. The invention incorporates a nonlinear mechanical transformer as part of an EMVD system. The nonlinear mechanical transformer is designed for the spring and the inertia in the EMVD to have desirable nonlinear characteristics. With the presently disclosed invention, the holding current and driving current are reduced and soft valve landing is achieved. The nonlinear characteristics of a nonlinear mechanical transformer can be implemented in various ways. The concept of the invention can be applied not only to EMVD's but also to general reciprocating and bi-stable servomechanical systems, where smooth acceleration, soft landing, and small power consumption are desired.