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:
Dec. 10, 1996
Filed:
May. 15, 1995
Hans-Peter Wirtz, Cologne, DE;
Ford Motor Company, Dearborn, MI (US);
Abstract
A pulse width modulated solenoid valve for control of hydrodynamic torque converters of automatic transmissions, comprising an electromagnetic switching element (11) and a valve body (12 ), wherein the valve body (12 ) has: an end (13 ) facing the switching element; an end (14 ) remote from the switching element; a control pressure chamber (15) for a fluid medium; a control spool (28) with at least one control groove (29a); a control pressure connection (20) to the control pressure chamber (15) for the fluid medium; at least one first pressure connection (22) connecting the control pressure chamber (15) to at least one outlet (21); at least one second pressure connection (24, 26) connecting at least one working chamber (16, 17) with at least one outlet (23, 25); at least one counter-pressure chamber (18) located at the opposite end of the valve body (12) to the control pressure chamber (15); at least one pressure connection (20, 22, 24, 26) being capable of being connected to at least one outlet (21, 23, 25) through a control groove (29a, 29b, 29c) on the control spool (28); wherein at least one spring element (27) is arranged in the counter-pressure chamber (18) the spring element (27) providing a counter-force to inhibit high accelerations of the control spool (28) in the direction away from the electromagnetic switching element (11).