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:
May. 13, 2003
Filed:
Jun. 19, 2001
Eric S. Keyster, Peoria, IL (US);
Dennis Gibson, Chillicothe, IL (US);
Caterpillar Inc, Peoria, IL (US);
Abstract
An axial piston pump with center inlet fill utilizes a hydrostatic thrust bearing and a hydrodynamic journal bearing to support a rotating wobble type drive plate connected to a drive shaft. The rotation of the drive plate causes a plurality of parallel pistons to reciprocate up and down. The pumping chambers of a portion of the pistons are fluidly connected via a center fill passage to the inlet defined by the pump housing. Simultaneously, the pumping chambers of a different portion of the pistons are fluidly connected to the outlet via a high pressure actuation fluid outlet passage. The center fill passage exploits centrifugal forces to assist, rather than resist, the supply of low pressure fluid to the pistons, especially when rotating at higher speeds.