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:
Sep. 30, 2003
Filed:
Aug. 30, 2001
Hiromichi Morita, Kariya, JP;
Goshin Ohashi, Kariya, JP;
Sojiro Tsuchiya, Nagoya, JP;
Hisatoshi Kojima, Toyota, JP;
Takayoshi Muto, Gifu, JP;
Hironao Yamada, Gifu, JP;
Denso Corporation, Kariya, JP;
Abstract
In a machine tool by pulse drive of a hydraulic system, a piston of a hydraulic cylinder is connected with a table, and an outflow valve and an inflow valve, which form a pair, are respectively connected with a right and a left hydraulic chamber. When the feed table is moved to the right, for example, control is conducted so that the valve-opening period of one valve can be a portion in the middle of the valve-opening period of the other valve. Since a portion of pressure in the hydraulic chamber is canceled, an effective pressure, the pulse width of which is narrow, remains. Accordingly, even in the case where a common inexpensive electromagnetic valve is used, it is possible to accomplish a smooth feed motion.