Motor-driven fuel pump

• US 5,141,410 A
• Filed: 11/19/1990
• Issued: 08/25/1992
• Est. Priority Date: 11/22/1989
• Status: Expired due to Term

• Current Assignee: Aisan Kogyo Kabushiki Kaisha
• Original Assignee: Aisan Kogyo Kabushiki Kaisha
• Inventors: Fujii, Shinichi
• Primary Examiner(s): Bertsch, Richard A.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/615,264
• Time in Patent Office: 645 Days
• Field of Search: 417/423.7, 310/51, 310/239
• US Class Current: 417/423.7
• CPC Class Codes: F02M 2037/082 Details of the entry of the current supply lines into the pump housing, e.g. wire connectors, grommets, plugs or sockets
• CPC Class Codes: F02M 37/08 electrically driven
• CPC Class Codes: F04D 13/06 the pump being electrically driven
• CPC Class Codes: H02K 11/026 Suppressors associated with brushes, brush holders or their supports
• CPC Class Codes: H02K 5/12 specially adapted for operating in liquid or gas combined with cooling arrangements H02K9/00
• CPC Class Codes: H02K 5/148 Slidably supported brushes
• CPC Class Codes: H02K 5/225 Terminal boxes or connection arrangements specially adapted for submersible motors H02K5/132

Abstract

A motor-driven fuel pump including a cylindrical pump casing having top and bottom ends; a pump section; a motor section has a motor shaft, an armature and a commutator. A spring loaded brush has one end contacting the cummutator and a second end connected to a choke coil. A terminal plate includes one end connected to an external power supply and the other end connected to the choke coil. A cover assembly for the pump casing provides a cover body with an opening holding a bearing, and appropriate recesses for accommodating the brush, spring, and choke coil components. A valve opening through which fuel is discharged from the pump section is provided. Simplification of the steps of assembling the various parts into the cover body is accomplished.

Claims

1. A motor-driven fuel pump comprising:

a substantially cylindrical pump casing having a lower and upper end;

a motor section accommodated in said pump casing, said motor section having a motor shaft for rotating an armature fixedly mounted on said motor shaft, and a commutator fixed to an upper end surface of the armature;

a pump section provided at the lower end of said pump casing, said pump section having an impeller fixedly mounted on said motor shaft to be rotated and to suck fuel from outside of said pump casing and to discharge the fuel into said pump casing under pressure;

a complete assembly cover provided at the upper end of said pump casing, said cover assembly comprising a cover body, said cover body having a central opening for insertion of a bearing, a first receptacle for accommodating a brush and a spring, a second receptacle for accommodating a choke coil, a recess between said first and second receptacles to accommodate a connector means,

and a discharge opening for discharging the fuel from said pump section to the outside of said pump;

a bearing inserted into said central opening for rotatably supporting an end portion of said motor shaft;

a brush having one end contacting said commutator and having a deformably extending pig tail shaped conductor at the other end;

a spring for biasing the other end of said brush to make pressure contact of the same with said commutator;

a terminal plate having one end to be connected to an external power supply;

a choke coil having one end connected to said pig tail shaped conductor and having the other end connectable to the other end of said terminal plate; and

said brush connector means and choke coil are pre-assembled as a unit and inserted into said first and second receptacles so that the connector means rests in said recess, said choke coil to said terminal plate and said spring is inserted whereby the cover assembly is complete.

2. The motor-driven fuel pump as defined in claim 1 wherein said connector means for connecting said brush to said one end of said choke coil comprises a connecting portion extending in a longitudinal direction of said first receptacle for the brush and a spring seat portion extending perpendicularly from said connecting portion for seating said spring, wherein a distance between said spring seat and said other end of said brush under a maximum extended condition of said pig tail shaped conductor is shorter than a length of said spring under an uncompressed condition thereof, so that said spring is interposed under compression between said spring seat and said other end of said brush.

3. The motor-driven fuel pump as defined in claim 2, wherein said pig tail of said brush and said other end of said choke coil are welded to said connecting portion of said connector.

4. The motor-driven fuel pump as defined in claim 2, wherein said cover body is integrally formed of resin with said terminal plate insert-molded.

5. The motor-driven fuel pump as defined in claim 2, wherein said brush is connected through said connector to said choke coil to form an assembly for positioning in said cover such that said brush is inhibited from coming out of said first receptacle and said choke coil is inhibited from coming out of said second receptacle by welding the connection of said other end of said choke coil with said other end of said terminal plate.

6. The motor-driven fuel pump as defined in claim 1 further comprising a check valve provided in said through-hole for allowing outward flow of the fuel from said pump casing to the outside thereof but inhibiting flow counter to said outward flow.