David K Beavers

US Patent:

20220409875, Dec 29, 2022

Filed:

Jul 19, 2022

Appl. No.:

17/867883

Inventors:

- Manchester NH, US
Paul G. Girouard - Allenstown NH, US
Jacob W. Scarpaci - Manchester NH, US
Geoffrey P. Spencer - Manchester NH, US
David A. Beavers - Manchester NH, US
Daniel B. Singer - Enfield CT, US
David B. Doherty - Litchfield NH, US

Assignee:

DEKA Products Limited Partnership - Manchester NH

International Classification:

A61M 39/22
A61M 60/43
A61M 60/113
A61M 5/145
A61M 5/155
A61M 5/142
A61M 60/538
A61M 60/38
A61M 60/837
A61M 60/37

Abstract:

Improvements in fluid volume measurement systems are disclosed for a pneumatically actuated diaphragm pump in general, and a peritoneal dialysis cycler using a pump cassette in particular. Pump fluid volume measurements are based on pressure measurements in a pump control chamber and a reference chamber in a two-chamber model, with different sections of the apparatus being modeled using a combination of adiabatic, isothermal and polytropic processes. Real time or instantaneous fluid flow measurements in a pump chamber of a diaphragm pump are also disclosed, in this case using a one-chamber ideal gas model and using a high speed processor to obtain and process pump control chamber pressures during fluid flow into or out of the pump chamber.