Self-priming pump system

• US 4,780,050 A
• Filed: 10/01/1987
• Issued: 10/25/1988
• Est. Priority Date: 12/23/1985
• Status: Expired due to Term

• Current Assignee: Sundstrand Corporation (Rtx Corporation)
• Original Assignee: Sundstrand Corporation (Rtx Corporation)
• Inventors: Tyler, Thomas, Caine, Gerard, Sailer, Thomas, Mosure, Duane
• Primary Examiner(s): Garrett, Robert E.
• Assistant Examiner(s): KWON, JOHN
• Application Number:
  US07/104,571
• Time in Patent Office: 390 Days
• Field of Search: 415/11.52, 415/53 R, 415/143, 55/159, 55/218
• US Class Current: 415/56.1
• CPC Class Codes: F04D 9/005 by adducting or recycling liquid F04D9/006 takes precedence

Abstract

To achieve priming during start-up and repriming during operation, a self-priming pump system is provided. The self-priming pump system includes a discharge priming reservoir for storing priming liquid for a pump. The discharge priming reservoir has an inlet in communication with the outlet of the pump for receiving priming liquid from the pump and has an outlet in communication with the pump upstream of an impeller and downstream of a liquid supply reservoir for supplying the priming liquid to the pump. The self-priming pump system is operable to separate air from priming liquid in the discharge priming reservoir during recirculation of priming liquid. In addition, a priming valve is disposed between the discharge priming reservoir and the pump to control circulation of priming liquid through the self-priming pump system.

Claims

1. A system for priming a pump during startup and repriming a pump during operation, comprising:

a pump having an inlet and an outlet, an impeller disposed between said inlet and said outlet, and an inducer disposed between said inlet and said impeller;

said inlet, inducer, impeller and outlet defining a primary flow path through said pump;

a liquid reservoir in communication with said pump through said inlet;

a recirculation loop including a separate discharge priming reservoir outside of said primary flow path for storing priming liquid for said pump, said recirculation loop having an inlet conduit extending from said separate discharge priming reservoir and in communication with said pump at said outlet for delivering priming liquid from said pump to said separate discharge priming reservoir and said recirculation loop also including an outlet conduit extending from said separate discharge priming reservoir and in communication with said pump downstream of said inlet between the ends of said inducer for delivering priming liquid from said separate discharge priming reservoir directly to said pump, said recirculation loop including means outside of said primary flow path and associated with said separate discharge priming reservoir for separating air from priming liquid delivered from said pump;

a priming valve disposed in said outlet conduit between said separate discharge priming reservoir and said pump, said priming valve being adapted to be opened at startup for priming said pump and during operation for repriming said pump by allowing priming liquid to flow freely through said inlet conduit for circulation from said separate discharge priming reservoir directly to said pump at said inducer, through said inducer and said impeller, and through said outlet of said pump back to said separate discharge priming reservoir, said inducer and impeller causing air in said inlet of said pump to be entrained in and pumped with said priming liquid for removal and venting of air from said separate discharge priming reservoir; and

means for opening and closing said priming valve during operation of said pump, said opening and closing means being adapted to ensure said pump is always maintained in a fully primed condition.

2. The self-priming pump system as defined by claim 1 wherein said pump comprises a contrifugal fuel pump for an aircraft and said liquid supply reservoir comprises a fuel tank for said aircraft.

3. The self-priming pump system as defined by claim 1 wherein said outlet conduit is in communication with said pump through a radially disposed injection port.

4. The self-priming pump system as defined by claim 1 wherein said means for separating air from priming liquid includes an inlet port in communication with said outlet of said pump to receive said priming liquid and air from said pump.

5. The self-priming pump system as defined by claim 4 wherein said separate discharge priming reservoir includes vent means disposed above said priming liquid, said vent means accommodating release of air removed from priming liquid to atmosphere externally of said separate discharge priming reservoir.

6. The self-priming pump system as defined by claim 5 wherein said outlet conduit of said discharge priming reservoir is in communication with said priming liquid through an outlet port below the priming liquid directly surface level in remote relation to said vent means to carry priming liquid to said pump for further entrainment of air during priming.

7. The self-priming pump system as defined by claim 1 wherein said opening and closing means is responsive to fluid pressure in said pump to control operation of said priming valve.

8. The self-priming pump system as defined by claim 1 wherein said priming valve is an electrically operated solenoid actuated valve and said opening and closing means includes a switch and a check valve integrally associated with said priming valve responsive to pressure in said pump inlet.

9. The self-priming pump system as defined by claim 1 wherein said liquid supply reservoir is normally disposed below said pump and said separate discharge priming reservoir is normally disposed above said pump.