초록 ▼

A gas pressure driven fluid pump comprising a pump tank having a liquid inlet and a liquid outlet. A float, carried within the interior of the pump tank, is operable to move between a low level position and a high level position. A snap-acting valve is operatively connected to the float. The snap ac

A gas pressure driven fluid pump comprising a pump tank having a liquid inlet and a liquid outlet. A float, carried within the interior of the pump tank, is operable to move between a low level position and a high level position. A snap-acting valve is operatively connected to the float. The snap acting valve has a rotatable port member that moves so as to switch to exhaust porting when the float falls to the low level position. The port member further switches to motive porting when the float rises to the high level position. As a result, fluid filling the pump tank causes the float to rise from the low level position to the high level position during exhaust porting. Fluid exiting the pump tank causes the float to fall from the high level position to the low level position due to introduction of motive gas during motive porting.

대표청구항 ▼

What is claimed is: 1. A gas pressure driven fluid pump, said pump comprising: a source of pressurized gas; a pump tank having a liquid inlet and a liquid outlet; a float carried within the interior of said pump tank, said float being operable to move between a low level position and a high level p

What is claimed is: 1. A gas pressure driven fluid pump, said pump comprising: a source of pressurized gas; a pump tank having a liquid inlet and a liquid outlet; a float carried within the interior of said pump tank, said float being operable to move between a low level position and a high level position; an exhaust valve in fluid communication with said pump tank, said exhaust valve capable of switching between an open position and a closed position; a motive valve in fluid communication with said pump tank, said motive valve being separate from said exhaust valve and capable of switching between an open position that allows fluid communication with the source of pressurized gas and a closed position that prevents fluid communication with the source of pressurized gas; a pilot valve operatively connected to said float and controlling operation of both said exhaust valve and said motive valve, said pilot valve operable to switch said exhaust valve to said open position and said motive valve to said closed position when said float falls to said low level position and to switch said exhaust valve to said closed position and said motive valve to said open position when said float rises to said high level position, wherein said pilot valve is operative to supply a motive valve pilot signal to said motive valve when said float reaches said low level position and is operative to supply an exhaust valve pilot signal to said exhaust valve when said float reaches said high level position; and whereby liquid filling said pump tank causes said float to rise from said low level position to said high level position when said exhaust valve is open and liquid exiting said pump tank causes said float to fall from said high level position to said low level position due to introduction of the pressurized gas when said motive valve is open. 2. The pump as set forth in claim 1, wherein said pilot valve is a rotary snap-acting valve. 3. The pump as recited in claim 1, wherein said exhaust valve has an exhaust valve actuation port and moves from said open position to said closed position responsive to said exhaust valve pilot signal at said exhaust valve actuation port. 4. The pump as recited in claim 1, wherein said motive valve has a motive valve actuation port and moves from said open position to said closed position responsive to said motive valve pilot signal at said motive valve actuation port. 5. The pump as recited in claim 3, wherein said exhaust valve is a disc valve. 6. The pump as recited in claim 4, wherein said motive valve is a disc valve. 7. The pump as recited in claim 1, wherein a single gas communication port provides fluid communication between said pump tank, said exhaust valve and said motive valve. 8. The pump as recited in claim 1, wherein said motive valve is located outside said pump tank. 9. The pump as recited in claim 8, wherein said exhaust valve is located outside said pump tank. 10. The pump as recited in claim 1, wherein said pilot valve is connected to said source of pressurized gas so as to produce pilot signals therefrom. 11. A gas pressure driven fluid pump, said pump comprising: a pump tank having a liquid inlet and a liquid outlet; a float carried within the interior of said pump tank, said float being operable to move between a low level position and a high level position; pilot switching means operatively connected to said float for generating a first pilot signal when said float rises from said low level position to said high level position and generating a second pilot signal when said float falls from said high level position to said low level position, said first and second pilot signals being positive pressure actuation signals; pump control means for switching fluid communication with the interior of said pump tank between a source of pressurized gas and an exhaust sink, wherein said pump control means switches to the source of pressurized gas in response to said second pilot signal of said pilot switching means and the exhaust sink in response to said first pilot signal of said pilot switching means; and whereby liquid filling said pump tank causes said float to rise from said low level position to said high level position and liquid exiting said pump tank causes said float to fall from said high level position to said low level position due to introduction of the pressurized gas within said pump tank. 12. The pump as recited in claim 11, wherein said pilot switching means is a pilot valve. 13. The pump as recited in claim 12, wherein said pilot valve is a rotary snap-acting valve. 14. The pump as recited in claim 12, wherein said pilot valve is located outside said pump tank. 15. The pump as recited in claim 11, wherein said pump control means is located outside of said pump tank. 16. The pump as recited in claim 11, wherein said pump tank contains a single port that allows fluid communication with said pump control means. 17. The pump as recited in claim 11, wherein said pump control means comprises: an exhaust valve in fluid communication between said pump tank and said exhaust sink, said exhaust valve switching to a closed position in response to said second pilot signal of said pilot switching means; and a motive valve in fluid communication between said pump tank and said source of pressurized gas, said motive valve switching to a closed position in response to said first pilot signal of said pilot switching means. 18. The pump as recited in claim 11, wherein said pump control means comprises at least one disc valve. 19. A system comprising: a pump tank with a liquid inlet and a liquid outlet; a rotary snap acting pilot valve operated by a float inside of said pump tank, said pilot valve being connected to a source of pressurized gas, said pilot valve snapping to a motive pilot signal position when the float reaches a first predetermined position and said pilot valve snapping to an exhaust pilot signal position when the float reaches a second predetermined position; an exhaust valve in fluid communication with said pump tank, said exhaust valve capable of switching between an open position and a closed position; a motive valve in fluid communication with said pump tank, said motive valve capable of switching between an open position and a closed position; a first conduit providing a fluid passage between said pilot valve and said exhaust valve to supply an exhaust pilot signal thereto, said exhaust pilot signal occurring when said pilot valve provides fluid communication between said source of pressurized gas and said exhaust valve; and a second conduit providing a fluid passage between said pilot valve and said motive valve to supply a motive pilot signal thereto, said motive pilot signal occurring when said pilot valve provides fluid communication between said source of pressurized gas and said motive valve.