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. 14, 2000
Filed:
Feb. 09, 1999
Myron D Tupper, Boring, OR (US);
Bill Gallentine, Hood River, OR (US);
Latch-Tool Development Co. LLC, Colorado Springs, CO (US);
Abstract
A hydraulic device includes a housing and a bulkhead disposed in the housing. A pump piston is provided in the housing and has first and second end surfaces with the second end surface of the pump piston and surfaces of the housing and of the bulkhead defining a pumping chamber. The pump piston is constructed and arranged to move within the housing to develop pressure on fluid in the pumping chamber. The first end surface of the pump piston and surfaces of the housing define a pump reservoir chamber. A ram piston is provided in the housing and has first and second end surfaces with the first end surface of the ram piston and surfaces of the housing and of the bulkhead defining a drive chamber. Connecting structure is associated with the bulkhead to communicate the pumping chamber with the drive chamber so that fluid pressure developed in the pumping chamber may be exerted on the first end surface of said ram piston. A barrier is provided in the housing between an end of the housing and the ram piston. Surfaces of the housing, the barrier and the second end surface of the ram piston define a ram reservoir chamber, and surfaces of the second end of the housing and of the barrier define an accumulator chamber. Passage and valve structure is associated with the barrier to selectively permit fluid to flow from the ram reservoir chamber to the accumulator chamber and from the accumulator chamber to the ram reservoir chamber. Passage and valve structure is associated with the ram piston to permit fluid flow from the ram reservoir chamber to the drive chamber. Passage and valve structure is associated with the pump piston to selectively permit fluid flow from the pump reservoir chamber to the pumping chamber and from the pumping chamber to the pump reservoir chamber, Communication structure fluidly communicates the accumulator chamber with the pump reservoir chamber. The ram piston is movable selectively at three speeds with corresponding magnitudes of force relative to a single speed of the pump piston.