Accelerated heart valve testing apparatus and methods
First Claim
1. Valve testing apparatus for testing of check valves such as prosthetic heart valves by application of repeated oscillatory flows produced by fluid motion relative to the valves, said apparatus comprising chamber means for receiving a plurality of test samples comprising valves to be tested, said chamber means defining fluid flow passages communicating with the valves for directing an oscillating flow of fluid to said test samples, at least first and second bellows respectively connected with the fluid flow passages, and a swash plate carrying the bellows, means for rotatably driving the swash plate for producing rotatably tilting oscillatory movement of the bellows, and a further fluid passage connecting the test samples for providing a fluid path extending between the bellows and including bypass passage means for receiving fluid from each of the passages respectively communicating with the bellows, and bypass flow control means, for selectively permitting the fluid to bypass the respective test valves through the bypass passages means thereby to control the fluid pressure to which the valves undergoing testing are exposed.
3 Assignments
0 Petitions
Accused Products
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.
-
Citations
14 Claims
- 1. Valve testing apparatus for testing of check valves such as prosthetic heart valves by application of repeated oscillatory flows produced by fluid motion relative to the valves, said apparatus comprising chamber means for receiving a plurality of test samples comprising valves to be tested, said chamber means defining fluid flow passages communicating with the valves for directing an oscillating flow of fluid to said test samples, at least first and second bellows respectively connected with the fluid flow passages, and a swash plate carrying the bellows, means for rotatably driving the swash plate for producing rotatably tilting oscillatory movement of the bellows, and a further fluid passage connecting the test samples for providing a fluid path extending between the bellows and including bypass passage means for receiving fluid from each of the passages respectively communicating with the bellows, and bypass flow control means, for selectively permitting the fluid to bypass the respective test valves through the bypass passages means thereby to control the fluid pressure to which the valves undergoing testing are exposed.
- 11. A method of durability testing of check valves such as prosthetic heart valves including positioning of at least one pair of such test valves with opposite orientations proximate the opposite ends of a fluid path for bidirectional exposure to oscillating movement of fluid in the fluid path, including imparting rapid oscillating movement of said fluid in the path with respect to the test valves, and characterized by permitting the fluid to bypass the test valves according to a predetermined inertial pressure differential, thereby to control the pressure of the oscillating fluid forces to which the test valves are exposed upon oscillation of the fluid.
Specification