Centrifugal system with pump for separating air from fuel

Apparatus for both pumping a liquid and removing air therefrom to permit accurate measurement of the volume of liquid being pumped, comprising:

• motor means for providing rotational energy to said apparatus;
• drive shaft means for receiving rotational energy from said motor means;
• vane pump means driven by said motor means for providing a self-priming pump for pumping any one of liquid, air, or a mixture of liquid and air, said vane pump means including:
• housing means including an inlet port for receiving any one of said liquid, or said air, or a mixture of liquid and air, and an outlet chamber for discharging the aforesaid;
• rotor means mounted upon a forward portion of said drive shaft means within said first housing means, for upon rotation "sucking" said liquid, or air, or mixture thereof from said inlet port and delivering the same under increased pressure to said outlet chamber, said outlet chamber being concentric with and about said drive shaft, the latter protruding therefrom;
• and
• centrifuge means for separating air from said liquid, said centrifuge means including:
• a cylindrical housing;
• a front baffle plate having a centrally located hole, said front baffle plate being rigidly connected across the front of said cylindrical housing and bolted to a back surface of said housing means of said vane pump means, said hole of said front baffle plate being both concentric with said drive shaft, and located for providing a passageway between said outlet chamber of said vane pump means and the interior of said cylindrical housing, said drive shaft protruding from said vane pump means through the hole of said baffle plate and into the interior of said cylindrical housing;
• an impeller having curved blades for providing lowered pressure passage along the central portion thereof and increased pressure passage at the extremities thereof, said impeller being rigidly mounted upon said drive shaft for rotation within said cylindrical housing;
• a rear baffle plate positioned across the back of said cylindrical housing, said rear baffle plate having a centrally located hole;
• an end cap bolted to the back of said cylindrical housing, said end cap having a protruding centrally located hub on its inside face, and a centrally located air vent hole in said hub leading into a radially located air vent hole through said end cap, said rear baffle plate being bolted to said hub with their respective centrally located holes being concentric to one another;
• an outlet port located towards the rear on the side of said cylindrical housing;
• and sump means connected to said vent hole of said end cap of said centrifuge means for receiving both low pressure air and residual liquid from said centrifuge means, for completing the removal of air from said liquid by permitting the air to "bubble-up" and out of the residual liquid;
• whereby upon rotation of said drive shaft, said vane pump means sucks liquid from a storage tank coupled to said inlet port of the former, and forces said liquid under pressure through the hole in said front baffle plate into said centrifuge means, where said rotating impeller causes air to be separated from said liquid and moved axially along the central portion of said impeller for exiting through the hole in said rear baffle plate at decreased pressure, and into the vent hole of said end cap of said centrifuge for venting from said centrifuge means into said sump means, said rotating impeller also causing liquid substantially free of air to be forced radially outward from said impeller against the interior surface of said cylindrical housing, for exiting therefrom into said outlet port at increased pressure for distribution, and
• metering means coupled to said outlet port for measuring liquid flowing from said outlet port substantially free of air.

A method for separating air from a liquid so as to permit accurate measurement of the volume of the liquid, using an apparatus including a vane pump rigidly attached to a centrifugal liquid/air separator, said separator including an impeller within a chamber, a liquid, inlet port, and an air vent port centrally located on a back face of said separator, said vane pump and separator having a common drive shaft, said vane pump including an inlet port for receiving liquid, and an outlet chamber, said method comprising the steps of:

• pumping liquid and air from said inlet port into said outlet chamber at a relatively high pressure;
• delivering said liquid and air into a relatively low pressure central area of said chamber in parallel with the longitudinal axis of said centrifugal separator while said impeller is rotating;
• directing relatively low pressure air extracted from said liquid axially and liquid combined with air along centrally located portions of said impeller into said air vent port;
• directing relatively high pressure liquid substantially free of air from the interior walls of said separator into said liquid outlet port for delivery under pressure to a receiving point;
• measuring liquid flowing from said outlet port substantially free of air;
• and
• venting said low pressure air and liquid combined with air into a sump having a free surface of liquid for allowing said air to escape from said liquid.