Patent ID: 11939968
Assignee: ALTRA, INC.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F  A | IPC A  F

Claim 14:
15. A pumping mechanism comprising:
(a) a chassis configured for removable attachment to a disposable cassette;
(b) a motor disposed within a length of the chassis and positioned in parallel to the flow path;
(c) a camshaft disposed adjacent to and in mechanical communication with the motor, wherein the camshaft comprises a plurality of lobes disposed along a length thereof;
(d) a first finger drive arm hingedly attached to the chassis and positioned parallel to the motor, wherein a bottom portion of the first finger drive arm is in mechanical communication with the camshaft and a top portion of the first finger drive arm has a plate configured to mechanically couple to a membrane of the disposable cassette;
(e) a second finger drive arm hingedly attached to the chassis and positioned opposing the first finger drive arm, wherein a bottom portion of the second finger drive arm is in mechanical communication with the camshaft, and wherein the first and second finger drive arms are 180° out of phase with each other and a top portion of the second finger drive arm has a plate configured to contact mechanically couple to the membrane of the disposable cassette;
(f) a plurality of strain gauges disposed on a surface of each of the first and second pumping finger drive arms in contact with the membrane of the disposable cassette and configured to monitor fluid pressure within first and second pumping chambers of the disposable cassette when attached thereto; and
(g) a plurality of valve arms hingedly attached to the chassis, wherein a lower portion of each valve arm is in mechanical communication with one of the plurality of lobes on the camshaft and an upper portion of each valve arm is configured to respectively actuate inlet valves and outlet valves of the disposable cassette,
wherein the pumping mechanism is configured such that the membrane of the disposable is not stretched while in use.