초록 ▼

Difficulties in adapting centrifugal pumps for use as fuel pumps for turbine powered aircraft are avoided in a system including a centrifugal volute pump (22) on a common shaft (18) with a regenerative pump (24). A pressure responsive throttling valve (46) is connected to the inlet (50) of the regen

Difficulties in adapting centrifugal pumps for use as fuel pumps for turbine powered aircraft are avoided in a system including a centrifugal volute pump (22) on a common shaft (18) with a regenerative pump (24). A pressure responsive throttling valve (46) is connected to the inlet (50) of the regenerative pump (24) so as to cause the regenerative pump (24) to provide fuel at a desired, substantially constant pressure while a check valve (80) is connected to the outlet (72) of the centrifugal volute pump (22) to allow flow from the volute (72) but not the reverse. The outlet side of the check valve (80) can also be selectively connected to the outlet (84) of the regenerative pump (24) so that when the pumps are rotating relatively slowly, the regenerative pump (24) will pump fuel at the desired, substantially constant pressure and, as rotational speed increases, the check valve (80) will open when the centrifugal volute pump (22) is pumping fuel at or about the desired substantially constant pressure.

대표청구항 ▼

[ We claim:] [9.] A fuel pump system for aircraft comprising:a source of fuel;a high speed pump including a rotatable shaft carrying a centrifugal impeller and a regenerative impeller, a housing having a first chamber containing said centrifugal impeller and having a volute, a first inlet and a firs

[ We claim:] [9.] A fuel pump system for aircraft comprising:a source of fuel;a high speed pump including a rotatable shaft carrying a centrifugal impeller and a regenerative impeller, a housing having a first chamber containing said centrifugal impeller and having a volute, a first inlet and a first outlet, said regenerative impeller and having a second inlet and a second outlet;means connecting said inlets to said source;means connecting said outlets to each other and to a fuel delivery point;a check valve connected to said first outlet upstream of said connecting means; anda pressure responsive throttling valve having a pressure responsive surface connected to sense the pressure at said outlets and having a fuel flow passage disposed between said source and said second inlet, and operable to increasingly throttle fuel flow to said second inlet as the pressure at said outlets increases to maintain the pressure at said second outlet substantially constant at a desired value, and to close said fuel flow passage when said desired value is achieved or exceeded.