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:
Mar. 17, 2009
Filed:
Feb. 06, 2006
Xingen Dong, Greeneville, TN (US);
William Power, Greeneville, TN (US);
Xingen Dong, Greeneville, TN (US);
William Power, Greeneville, TN (US);
Parker-Hannifin Corporation, Cleveland, OH (US);
Abstract
Improvements in trunnion shaft-controlled swashplate axial hydraulic piston pumps as well as hydraulic systems used in hydrostatic transmissions utilized. e.g., in zero-turn-radius (ZTR) wheeled vehicles, such as grass mowers, with one embodiment thereof pertaining to, in combination, the noted pump, devoid of any internal servo control, and a reversible power actuator, for controlling the angle of the swashplate, externally affixed to the housing containing the pump and operatively interconnected with an end of the trunnion shaft extending from the pump housing, with the power actuator being one of a rotary actuator, a fluid power axial cylinder and a rotary electronic actuator. Usage in a ZTR wheeled vehicle requires the prime mover to independently drive two hydraulic transmissions that are controlled by a human operator via a mechanical lever, either two single-axis or one dual-axis joystick control, or a steer-by-wire unit, connected with right and left power actuators