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:
Aug. 18, 1998
Filed:
Apr. 03, 1997
Donald G Bethke, Delafield, WI (US);
Other;
Abstract
An axial piston pump assembly includes a housing having an outer wall defining a generally cylindrical interior and an end wall. A drive shaft extends through the end wall is rotatably mounted in the housing for rotation on the axis of the cylindrical interior, and the rotor is attached to the drive shaft for rotation therewith. A plurality of circumferentially spaced, axially disposed cylinders is positioned in the rotor, and a series of axially reciprocable pistons is disposed in the cylinders. A swashplate surrounds the drive shaft and is mounted in the housing for tilting movement on a tilt axis transverse to the drive shaft axis. A planar reaction surface on the swashplate is engaged by the outer ends of the pistons. A biasing arrangement is provided for urging the piston ends into engagement with the reaction surface, and a control arrangement is supplied for tilting the swashplate on its axis to maintain the reaction surface angularly disposed with respect to the axis of the drive shaft. A pair of inboard trunnion blocks is adjustably attached to the interior of the housing end wall on opposite sides of the drive shaft and supports the swashplate on a rear surface opposite the reaction surface for tilting movement thereon. The control arrangement resides in a cooperating piston arrangement acting in opposed relationship against the reaction surface and the rear surface of the swashplate to eliminate the bending moments induced by the axially reciprocable pistons and biasing means about the tilt axis of the swashplate.