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. 16, 2003
Filed:
Apr. 11, 2002
Jürgen Legner, Friedrichshafen, DE;
ZF Friedrichshafen AG, Friedrichshafen, DE;
Abstract
In order to reduce the shock that occurs in downshifting and up-shifting a hydraulic radial piston engine, a valve ( ), which controls the displacement of the radial piston engine, is reversed with throttling. In order to prevent the throttled reversal from being affected by the level of pressure in the hydraulic fluid intake ( ) to the hydraulic radial piston engine, a sealing point is provided in the valve ( ), which controls the hydraulic fluid intake ( ) to the torque-generating pistons. To prevent critical safety situations from arising, a valve ( ) is positioned in front of the valve ( ) that controls the displacement of the hydraulic radial piston engine; this valve ( ) always switches the valve ( ) that controls the displacement of the hydraulic radial piston engine, without pressure, when the hydraulic fluid intake ( ) from a hydraulic fluid source to the hydraulic radial piston engine falls below a certain pressure level.