Claims
- 1. A flow meter for indicating an output of a pump comprising:a) a housing defining an internal chamber, a primary inlet for receiving the output of the pump, an outlet in fluid communication with the primary inlet through a passageway formed in the housing, and a secondary inlet for receiving a scavenged portion of the output passing through the outlet; and b) a valve member slidingly received within the internal chamber for varying flow through the passageway such that the output of the pump and the scavenged portion each exert a force on the valve member, wherein a first force exerted by the scavenged portion is a downstream reference pressure opposing a second force exerted by the output of the pump.
- 2. A flow meter as recited in claim 1, further comprising a spring for coupling the valve member to an elongated arm.
- 3. A flow meter as recited in claim 1, further comprising a spring between the valve member and the housing for applying a biasing force to the valve member.
- 4. A flow meter for dampening responses to minor transients in fuel flow to an engine, the flow meter comprising:(a) a housing forming an interior chamber, the interior chamber having i) a first chamber; ii) a second chamber; iii) an inlet in fluid communication with the first chamber for connection to a high pressure outlet of the vane pump; iv) an outlet in fluid communication with the first chamber for connection to the engine, v) a port in fluid communication with the second chamber, and vi) a passage connecting the port to the outlet of the flow meter to provide a downstream reference to the second chamber of the flow meter; and (b) a valve member slidingly received in the interior chamber of the housing for varying fuel flow from the inlet to the outlet, and dividing the housing into the first and second chambers, wherein increased fuel flow from the pump through the first chamber causes the valve member to move away from the inlet.
- 5. A flow meter as recited in claim 4, further comprising an orifice formed in the passage for restricting an amount of fluid which may be displace by the valve member.
- 6. A flow meter as recited in claim 4, further comprising a plunger slidingly mounted in the housing for movement with the valve member.
- 7. A flow meter as recited in claim 6, further comprising a compression spring operatively positioned between the plunger and the housing to provide a biasing force.
- 8. A flow meter as recited in claim 4, wherein the housing is unitarily formed with a second housing of the pump.
CROSS-REFERENCE TO RELATED APPLICATION
The present application is a divisional application of U.S. patent application Ser. No. 09/867,359, filed on May 29, 2001 now U.S. Pat. No. 6,623,250, which is a continuation-in-part of U.S. patent application Ser. No. 09/506,465 filed Feb. 17, 2000 now abandoned, the disclosure of which is herein incorporated by reference in its entirety.
US Referenced Citations (54)
Foreign Referenced Citations (2)
Number |
Date |
Country |
1 048 842 |
Feb 2000 |
EP |
2 764 336 |
Dec 1998 |
FR |
Non-Patent Literature Citations (1)
Entry |
Communication: European Search Report for Ser. No. 02010074.9, Aug. 22, 2003. |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
09/506465 |
Feb 2000 |
US |
Child |
09/867359 |
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US |