In-take fuel pump assembly with unitary control unit for internal combustion engines

• US 5,961,293 A
• Filed: 07/29/1996
• Issued: 10/05/1999
• Est. Priority Date: 05/19/1995
• Status: Expired due to Term

• Current Assignee: UCS Incorporated (UCI International Holdings, Inc.)
• Original Assignee: UCS Incorporated (UCI International Holdings, Inc.)
• Inventors: Ulm, Ralph E., Clemmons, Robert T.
• Primary Examiner(s): FREAY, CHARLES GRANT
• Application Number:
  US08/681,738
• Time in Patent Office: 1,163 Days
• Field of Search: 417/44.2, 417/44.9, 417/423.3, 417/423 R, 417/423.13, 417/423.14, 417/424.1, 417/410.3, 417/410.4
• US Class Current: 417/44.2
• CPC Class Codes: F02M 37/10 submerged in fuel, e.g. in reservoir
• CPC Class Codes: F04C 14/06 specially adapted for stopping, starting, idling or no-load operation
• CPC Class Codes: F04C 14/08 characterised by varying the rotational speed

Abstract

An in-tank fuel pump apparatus includes an elongated motor-pump unit having a motor and pump unit connected in end-to-end relation. An outer cam has a substantially constant diameter enclosing the motor-pump unit and projecting axially outwardly therefrom and defining a control chamber immediately adjacent the one end of the motor-pump unit. A control tower is secured to the end of the motor-pump unit from which the motor cam extends. The control tower includes a body member having a closure plate abutting the motor pump unit, an outlet passageway extending axially from the motor-pump unit to the exterior of the motor cam, a pressure sensor secured within the body member having an inlet connected to a sensing passage connected to the output of the motor pump unit in an outermost circuit board forming the outermost end of the tower unit. An epoxy resin fills the unit about the several elements between the motor and the outer end of the cam and includes all voids within the tower structure to seal the control components against fuel and support the components as a single unitary assembly above the motor-pump unit. The tower is separately assembled as formed as a separate self-contained sub-assembly mounted within the outer housing and then with an epoxy resin introduced to fill the cavity and support all of the control, power and sensing components as a unitary complete control unit and outlet passage from the motor unit.

Claims

1. A fuel pump assembly for in-tank mounting for supplying fuel from a fuel tank to an internal combustion engine under a controllable pressure, comprising a motor-pump unit including an elongated motor and a pump unit secured to one end of said motor and adapted to pump fuel from the fuel tank, said motor-pump unit having a first end and a second end, an inlet unit secured to said first end of said motor-pump unit and extending outwardly thereof and closing the first end of said motor-pump unit, said inlet unit having a fuel inlet for entry of fuel into said motor-pump unit, a control tower unit secured to said second end of the said motor-pump unit and closing the second end of said motor-pump unit, and said control tower unit including an outlet passageway connected to said second end of said motor-pump unit for delivery of fuel therefrom and a control system including a pressure responsive unit and a circuit control unit connected to control the power supplied to said motor.

2. The fuel pump assembly of claim 1 including an outer can enclosing said motor-pump unit, said inlet unit and said control tower unit.

3. The fuel pump assembly of claim 2 including an encapsulating and supporting material filling said can about said control tower unit.

4. The fuel pump assembly of claim 2 wherein said control tower unit includes a body member having a closure plate secured abutting the motor-pump unit and having a peripheral seal to said outer can, said outlet passageway being located in said body member and extending axially outwardly from the motor-pump unit to the exterior of said can, said body member including a sensing passageway connected to said second end of said motor-pump unit configured with a fuel output, said pressure responsive unit including a pressure sensor secured to said body member within said can and having an inlet connected to said sensing passageway, said control system including a control circuit board mounted within said can and secured to said body member, said circuit board having supply terminals projecting outwardly and exposed at the outer end of said can, a cooling member interconnected to the interior of said can, a power switch unit located within said tower unit and including a solid state switch unit secured to said cooling member, said circuit board having circuit means interconnected to said pressure sensor and to said solid state switch and to said power supply terminals and to said motor to establish energization of said motor in accordance with the output pressure of said motor-pump unit and establishing an essentially controlled constant pressure of the fuel supply to said engine.

5. The fuel pump assembly of claim 4 including an encapsulating material filling said can about said tower unit to enclose said components of said tower unit.

6. The fuel pump assembly of claim 4 wherein said can has an essentially constant diameter and defining an elongated construction for mounting within the fuel tank.

7. The fuel pump assembly of claim 1 wherein said tower includes an axially extended sensing opening generally parallel to the extension of the tower, said pressure responsive unit including a pressure sensor having a housing located within said opening and includes a sensing diaphragm member closing said outer end of said opening and a pressure sensing die element in said housing, said diaphragm being formed of a material non-reactive and non-destructive with respect to said fuel, said sensor having a chamber with a pressure responsive electrical signal source secured within said chamber, an hydraulic gel filling said chamber and transmitting pressure on said diaphragm to said die element and thereby generating a signal related to the pressure on said diaphragm, said sensor terminals connected to said pressure sensing die element.

8. The fuel pump assembly of claim 7 wherein said diameter opening and said diaphragm being fixedly secured to said chamber in a fluid type relationship thereto.

9. The fuel pump assembly of claim 7 wherein said opening and sensor are located radially offset from the axis of the tower.

10. The fuel pump assembly of claim 7 wherein said diaphragm is a flexible metal plate.

11. The fuel pump assembly of claim 10 wherein said plate is a stainless steel plate.

12. A fuel pump assembly for in-tank mounting for supplying fuel from a fuel tank to an internal combustion engine under a controllable pressure, comprising an elongated motor-pump unit adapted to pump fuel from the fuel tank, a control tower unit secured to one end of said motor-pump, and said control tower unit including an outlet passageway for delivery of fuel therefrom and a control system including a pressure responsive unit and a circuit control unit connected to control the power supplied to said motor, and said motor-pump unit and said control tower unit being enclosed within a sealed enclosure including a fuel inlet and a fuel outlet.

13. The fuel pump assembly of claim 12 wherein said enclosure includes an outer can enclosing said motor-pump unit, and said control tower unit, and an encapsulating and supporting material filling said can about said control tower unit.

14. The fuel pump assembly of claim 13 wherein said control tower unit includes a body member having a closure plate secured abutting the motor-pump unit and having a peripheral seal to said outer can, said motor-pump unit including an outlet at said closure plate, said outlet passageway in said body member extending axially outwardly from said outlet of the motor-pump unit to the exterior of said can, said body member including a sensing passageway connected to the outlet of said closure plate of said motor-pump unit, said pressure responsive unit includes a pressure sensor secured to said body member within said can, said sensor having a sensing chamber with a pressure inlet connected to said sensing passageway, a sensing die located in said sensing chamber and responsive to pressure to establish a related output signal, a diaphragm closing said sensing inlet, a gel filling said sensing chamber, said control unit including a control circuit board mounted within said can and secured to said body member, and said circuit board having power supply terminals projecting outwardly and exposed at the outer end of said can and having a control circuit connected to supply power to said motor-pump unit in accordance with said output signal.

15. The fuel pump assembly of claim 14 wherein said control circuit includes a solid state switch unit secured to a cooling member interconnected to the interior of said can, said circuit board having circuit means interconnected to said pressure sensor and to said solid state switch and to said power supply terminals and to said motor to establish energization of said motor in accordance with said output signal and establishing an essentially controlled constant pressure of the fuel supply to said engine.

16. The fuel pump assembly of claim 14 wherein said sensing passageway extends longitudinally of said can from said motor-pump unit, said sensing die having terminals extending from said pressure sensor longitudinally of said can through said circuit board for connection to said power terminals and said motor.

17. The fuel pump assembly of claim 13 wherein said can has an essentially constant diameter and defining an elongated tubular construction for mounting within the fuel tank.

18. The fuel pump assembly of claim 17 wherein said motor-pump unit is secured in one end of said can and said tower unit is secured in the opposite end of said can, said tower unit including a body member closing the end of the motor-pump unit having said sensing passage and outlet passageway.

19. A fuel pump apparatus for pumping of fuel from a fuel tank under a controllable pressure, comprising an elongated motor-pump unit including a motor and a pump unit secured to one end of said motor, an outer can having a substantially constant diameter enclosing said motor-pump unit and projecting axially therefrom and defining a control chamber immediately adjacent one end of said motor-pump unit, a control assembly mounted within said control chamber and including a support body having a closure portion of a diameter essentially corresponding to the internal diameter of said can adjacent one end of said motor-pump unit and sealing the end of the motor-pump unit, a pressure sensing unit and a control circuit mounted to said support body, said control circuit connected to said motor-pump unit and to said pressure sensing unit and responsive to said pressure sensing unit to provide controlled power to said motor-pump unit for establishing a controlled flow of fuel to the engine, said support body including an output passageway extending outwardly of said can for supplying of fuel therefrom.

20. The apparatus of claim 19 including a sealing and supporting compound filling of said control chamber to prevent entrance of fuel into said control chamber.

21. The apparatus of claim 19 wherein said support body is a molded plastic block having a circular plate abutting said motor-pump unit and sealed to said can by an O-ring seal, said output passageway formed in said block and projecting outwardly of said can and said control chamber and located adjacent to said can, said body having an enlarged body portion integral with the plate and said passageway and extending laterally across said control chamber, said circular plate and body portion having a bearing passageway aligned with the axis of said motor, said motor-pump unit having a supporting rotating shaft extended into said bearing opening and rotatably supported therein, said body portion including a sensing passageway communicating with said outlet and an axially extended opening connected to said sensing passageway, said pressure sensing unit secured within said axially extended opening and including an axially extended inlet port for sensing of the output pressure, said control circuit including a solid state switch chip, a cooling plate member in the form of a curved plate, said curved plate being located in abutting engagement with said can, said curved plate having a flat wall portion, an insulating material covering said flat wall portion, said solid state switch chip being secured in firm abutting engagement to said flat wall with the insulating material interposed therebetween, said insulating material and said cooling plate being constructed of a high thermal conductivity material for optimum cooling of said solid state switch chip, said curved cooling plate being located abutting said closure plate and projecting axially outwardly thereof about said body, said body having spaced contact openings extending axially through the body and said closure plate, contact units mounted within said contact openings and coupled to said motor at the interior of said closure plate for connection to said motor, contact posts secured in said contact openings coupled to said contact units and including outwardly projected contact posts having an outer threaded terminal connector, said circuit board including openings aligned with said contact opening and secured to said body with said contact posts projecting outwardly through said circuit board openings for receiving of clamping devices for clamping of said circuit board in abutting engagement with said posts and said outer cooling plate, said circuit board having a single set of supply power terminals projecting outwardly from said board and the open end of said can, and a sealing compound filling said control chamber to fully encapsulate the control chamber with said outlet passageway and said power terminals projecting outwardly thereof.

22. A motor-pump apparatus for pumping of fuel from a fuel tank under a controllable pressure, comprising an elongated motor-pump unit having an output, a unitary control unit abutting one end of said motor-pump unit, an attachment unit securing said unitary control unit to said one end of the motor-pump unit and extending outwardly therefrom, said unitary control unit including an outlet pipe extending through the control unit and connected to the output of the motor-pump unit, said unitary control unit having input power terminals and a pressure control unit and an electric circuit operable to control the motor-pump unit for pumping of fuel from the fuel tank under a controllable pressure, and said attachment unit including an outer enclosure having a substantially constant diameter enclosing said motor-pump unit and said unitary control unit to form an elongated controlled fuel flow assembly, wherein said pressure control unit includes a pressure sensing unit, a solid state power switch, a control circuit board including a control circuit connecting said switch to said motor and signal processing circuitry connected to and responsive to said pressure sensing unit and connected to turn said switch on and off to provide control power to said motor-pump unit.

23. A motor-pump apparatus for pumping of fuel from a fuel tank under a controllable pressure, comprising an elongated motor-pump unit having an output, a unitary control unit abutting one end of said motor-pump unit, an attachment unit securing said unitary control unit to said one end of the motor-pump unit and extending outwardly therefrom, said unitary control unit including an outlet pipe extending through the control unit and connected to the output of the motor-pump unit, said unitary control unit having input power terminals and a pressure control unit and an electric circuit operable to control the motor-pump unit for pumping of fuel from the fuel tank under a controllable pressure, and said motor-pump unit including an outer motor frame, said unitary control unit including a plastic body member having a wall at said one end extended into and secured to said motor frame and forming a motor end frame of said motor.