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:
Oct. 13, 1987
Filed:
Nov. 27, 1985
Don E Avery, Honolulu, HI (US);
Bryan F Young, Honolulu, HI (US);
Other;
Abstract
Two concentric vertical cylinders are separated by three radial partitions. An opening at the bottom of one of the partitions connects an air cell on one side of the partition with an outlet chamber on the other side of the partition. The two other partitions form sides of an inlet chamber, which receives fluid from outside the outer cylinder. The inner cylinder has a central pumping section positioned between upper and lower valve sections. In the valve sections ports extend through the inner cylinder wall to the inlet and outlet chambers. Spring loaded valves close the ports. Tension springs extend across the inlet chamber or compression springs extend across the inner cylinder to close the inlet valves. Tension springs extend across the inner cylinder to close the outlet valves. The elastomeric valve flaps have rigid curved backing members. A piston rod extends through one end cover to move a piston in the central section. An air tube extends between an upper end of the inner cylinder and the air cell, and check valves permit air to be trapped in the upper end of the cylinder and to flow to the cell.