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. 15, 1985
Filed:
Aug. 17, 1984
Wilbur M Swanson, St. Louis County, MO (US);
Dynatek, Inc., St. Louis, MO (US);
Abstract
Apparatus and methods for durability (fatigue) testing of prosthetic heart valves or other check valves. The apparatus is circular in plan and includes a test fixture in which the valves are circularly arranged, located with communicating passages, such passages communicating with bellows closed at one end. The bellows are carried by a swash plate journalled to a motor by a coupling providing an adjustable tilt axis. The tilt axis determines the amplitude of the motion or flow of the fluid, as the bellows alternately expand and contract. A central bypass chamber includes orifices which are selectively varied in effective cross section to control an amount of the test fluid which bypasses the test samples, thereby determining fluid pressure differential across the sample valves. Fluid in the apparatus can be heated by an electric heater to temperatures similar to human blood, a temperature probe monitoring the temperature for its control. A pressure tap monitors the fluid pressure for shutting down the apparatus if abnormal pressures or leaks are developed. Several prosthetic heart valves, e.g., two, four, six, eight, etc., are held by the fixture at the same time for life testing at relatively high cyclic rates.