Method and apparatus for calibrating pumps

Apparatus for determining the flow rate of a pump under test comprising:

• (a) a fluid receptacle;
• (b) an orifice having a known maximum flow rate;
• (c) means for pumping fluid via said orifice into said receptacle under sufficient pressure to maintain the maximum flow rate through said orifice;
• (d) means for alternately connecting one of said pumping means and said pump under test to said receptacle whereby the receptacle is filled by said pumping means and evacuated by the pump under test;
• (e) control means for operating said pumping means for a selected time period whereby the volume of fluid in the receptacle is known and for measuring the time required for the pump under test to evacuate the receptacle and calculating the flow rate of the pump under test from the known volume of fluid evacuated from the receptacle and the time required to evacuate it.

Apparatus for detecting the flow rate of a fluid evacuated from a receptacle comprising:

• (a) a fluid receptacle;
• (b) an orifice having a known maximum flow rate;
• (c) means for pumping fluid via said orifice into said receptacle under sufficient pressure to maintain the maximum flow rate through said orifice;
• (d) means connecting said pumping means to said receptacle in a first position and disconnecting said pumping means to permit evacuation of said receptacle in a second position;
• (e) control means for operating said pumping means for a selected time period whereby the volume of fluid in the receptacle is known and for measuring the time required to substantially evacuate the receptacle and calculating the flow rate of the pump under test from the known volume of fluid evacuated from the receptacle and the time required to evacuate it.