JPH03229962A - Motor-driven fuel pump for vehicle - Google Patents

Abstract

PURPOSE:To simplify structure and reduce the number of parts by providing a motor driven fuel pump with an electric motor, an upper and a lower cover bodies to be fitted to cover the electric motor, a pump casing plate and an impeller, and constructing this motor-driven fuel pump in such a way as to use the inside of the electric motor as a fuel flow passage. CONSTITUTION:A motor-driven fuel pump P is disposed through a stay so that a fuel intake pipe 24 positioned at the lower part is placed in proximity to the bottom face of a fuel tank, and a fuel discharge pipe 2 is provided at the upper part of the pump P. In this case, the motor-driven fuel pump P is formed of an electric motor 1, a lower cover body 2, an upper cover body 3, a pump casing plate 4 and an impeller 5. As the electric motor 1, a common type motor is adopted, and fuel inlets 6 are provided at plural places of the bottom face of the motor and fuel outlets 7 are provided at plural places of the top face, as well as the inside is formed into a fuel flow passage. The impeller 5 is accommodated in a pump chamber 11 between the pump casing plate 4 and the bottom plate part 9 of the lower cover body 2.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electric fuel pump that is disposed within a fuel tank of a vehicle such as an automobile.

(Prior Art) A conventional electric fuel pump has a fuel flow passage communicating between a fuel intake port and a fuel discharge port formed in a pump casing, and a pump chamber formed in the middle of the fuel flow passage, in which an electric motor is connected. It had an impeller driven by.

In addition, in order to reduce pump noise such as motor rotation noise, fuel flow noise, and impeller rotation noise,
As an example is shown in the publication, pumps are covered with special rubber soundproofing covers.

(Problems to be Solved by the Invention) In view of the above, the present invention has a small number of parts, a simple structure, a motor with a general shape, and a soundproofing effect without the need for a special soundproofing cover. The purpose of the present invention is to provide an electric fuel pump for vehicles that can be used in vehicles.

(Means for Solving the Problems) In order to achieve the above object, the present invention has a fuel flow passage inside, a fuel inlet at the bottom, a fuel outlet at the top, and a fuel outlet located below the center of the bottom. an electric motor having a protruding output shaft; a bottomed cylindrical lower cover body made of synthetic resin that is fitted over the electric motor, has a fuel inlet communicating with the pump chamber, and forms the lower surface of the pump chamber; , an upper cover body made of synthetic resin and having a crested cylindrical shape that is fitted over the electric motor and has a fuel outlet communicating with the fuel outlet of the electric motor; a bottom plate portion of the lower cover body; and a bottom surface of the electric motor; a pump casing plate located in the middle of the pump chamber and having a communication path that communicates the pump chamber with the fuel inlet of the electric motor and forming the upper surface of the pump chamber; and an impeller arranged in the pump chamber and fixed to the output shaft. The present invention provides an electric fuel pump for a vehicle characterized by comprising the following.

(Function) According to the present invention, by using the inside of the electric motor as a fuel flow path, the electric motor, the upper and lower cover bodies fitted over the electric motor, the pump casing plate, and the impeller can be separated from each other. An electric fuel pump for a vehicle can be constructed, the structure can be extremely simple, and the number of parts can be minimized as much as possible. Moreover, it is easy to form the upper and lower cover bodies and the pump casing plate to fit a motor of a general shape, and the electric motor has ventilation holes on its top and bottom surfaces, which are connected to the fuel outlet. Since it can be used as a fuel inlet, an electric motor of a general shape can be easily used.

Further, according to the present invention, since the upper and lower cover bodies cover the inside and are made of synthetic resin, it is advantageous to confine motor rotation noise, fuel flow noise, impeller rotation noise, etc. Therefore, soundproofing can be achieved without the need for a special soundproofing cover.

(Example) Embodiments of the present invention will be described based on FIGS. 1 and 2.

FIG. 2 shows a state in which the electric fuel pump P of the present invention is arranged in a fuel tank T of an automobile. The electric fuel pump P is supported by a stay 22 and arranged inside the fuel tank T, and the stay 22 is connected to the fuel tank T at its upper end.
It is fixed to the lid 23 of. The fuel suction pipe 24 located at the bottom of the pump P is close to the bottom surface of the fuel tank T.

A bag-shaped filter 25 that surrounds the fuel suction port 10 is attached to the fuel suction pipe 24, and the fuel in the fuel tank T is filtered by the filter 25, and then enters the pump P from the fuel suction port IO. is inhaled. A fuel discharge pipe 26 is provided at the top of the pump P, and the fuel discharged from the fuel discharge port 14 passes through a fuel hose 29 and a fuel supply tube 27 to a fuel supply device (not shown) to the engine such as a carburetor or an injector. ) will be sent to. Excess fuel in the fuel supply device passes through the return pipe 28 to the fuel tank T.
returned inside.

The electric fuel pump P is composed of an electric motor 1, a lower cover body 2, an upper cover body 3, a pump casing plate 4, and an impeller 5, as shown in FIG.

As the electric motor 1, a normal-shaped motor is used, and it is equipped with fuel ports 6 formed at multiple locations on the bottom surface, fuel outlet lowers formed at multiple locations on the top surface, and a fuel flow passage inside. It becomes. An output shaft 21 of the electric motor 1 projects downward from the bottom surface.

The lower cover body 2 is made of synthetic resin and has a cylindrical shape with a bottom, and is fitted onto the outer case 8 of the electric motor 1 . This lower cover body 2 covers most parts of the electric motor 1 except for the upper end part. Also, the bottom plate portion 9 of this lower cover body 2
The fuel suction pipe 24 is integrally formed with the fuel suction pipe 24, and the fuel in the fuel tank T is sucked into the pump from the fuel suction port 10 corresponding to the opening thereof.

A pump chamber 11 is formed on the upper surface of the bottom plate portion 9, and this bottom plate portion 9 constitutes a lower surface portion of the pump chamber 11. Note that the fuel intake port 10 communicates with the pump chamber 11. Further, the upper end opening periphery of the lower cover body 2 forms a flange portion 12 .

The upper cover body 3 is made of synthetic resin and has a cylindrical shape, and is fitted over the upper end of the outer case 8 of the electric motor 1 . The fuel discharge pipe 26 is integrally formed on the top plate portion 13 of the upper cover body 3, and the fuel in the pump is discharged from the fuel discharge port 14 corresponding to the opening thereof to the fuel hose 29. . A flow path 15 is formed between the top plate portion 13 and the top surface of the electric motor 1, and the lower fuel ratio of the electric motor 1 and the fuel discharge port 14 communicate with each other via the flow path 15. Note that the top plate portion 13 is provided with a relief hole 16 for pressure adjustment. Further, the periphery of the opening at the lower end of the upper cover body 3 forms a flange portion 17 .

A space is provided in the vertical direction between the bottom plate portion 9 of the lower cover body 2 and the bottom surface of the electric motor 1, and a pump casing plate 4 made of synthetic resin is interposed between the two. The pump casing plate 4 is fitted into the lower end of the cylinder of the lower cover body 2, and a pump chamber 11 is formed on the lower surface thereof. Therefore, this pump casing plate 4 constitutes the upper surface portion of the pump chamber 11. In addition, this pump casing plate 4
has a communication passage 18 that communicates the pump chamber 11 and the fuel supply 6 of the electric motor 1, and also has a support part 19 that supports the lower surface of the electric motor 1 and a center of the reservoir into which the output shaft 21 of the electric motor 1 is loosely inserted. It has an opening 20.

An impeller 5 is arranged in a pump chamber 11 formed between the pump casing plate 4 and the bottom plate part 9 of the lower cover body 2, and this impeller 5 is fixed to the output shaft 21 of the electric motor 1. .

As shown in FIG. 1, the lower cover body 2 incorporates an impeller 5, a pump casing plate 4, and an electric motor 1, and an upper cover body 3 is fitted over the upper end of the electric motor 1. In this state, both flanges 17.12 of the upper and lower cover bodies 3.2 are brought into contact with each other, and the metal plate ring 30 arranged around the outer periphery of these flanges 17.12 is caulked as shown in FIG. The upper and lower cover bodies 3.2 are connected. By connecting the upper and lower cover bodies 3.2 as described above, the electric motor 1 and the pump casing plate 4 are fixed in a predetermined position.

In FIG. 1, 31 is a vibration-proofing cap interposed between the pump P and the stay 22, 32 is a soft elastic ring interposed between the pump casing plate 4 and the electric motor 1, and 33 is a vibration-proofing cap interposed between the pump P and the stay 22. This is an O-ring interposed between the flanges 12 and 17.

In the electric fuel pump P having the above configuration, when the electric motor 1 is driven and the impeller 5 rotates, the fuel in the fuel tank T is sucked through the fuel intake port 10 and is pressurized by the impeller 5 in the pump chamber 11. The fuel is sent to the communication path 18, then enters the electric motor 1 through the fuel population 6, ascends the internal fuel flow path, and exits the electric motor 1 through the fuel ratio lower. The fuel reaches the fuel discharge port 14 via the passage 15, and is discharged from there to the fuel hose 29.

(Effects of the Invention) According to the present invention, the number of parts is small, the structure is simple, and -
It is possible to provide an electric fuel pump for a vehicle that can use a boat-shaped motor and can have a soundproofing effect without requiring a special soundproofing cover.

[Brief explanation of drawings]

FIG. 1 is a cutaway front view showing an embodiment of the present invention, and FIG. 2 is a side view thereof. Electric motor lower cover body Upper cover body Pump casing plate Impeller Fuel inlet 7 ----Fuel outlet 10-11-----1111--1-----
-1--Fuel inlet pump chamber 4 -------------------------Fuel discharge port 8 Series passage 1 Output shaft

Claims (1)

[Claims] (1) An electric motor with a fuel flow passage inside, a fuel inlet on the bottom and a fuel outlet on the top, and an output shaft protruding downward from the center of the bottom; a bottomed cylindrical lower cover made of synthetic resin, which is provided with a fuel inlet that communicates with the pump chamber and forms the lower surface of the pump chamber, and which is fitted over the electric motor and communicates with the fuel outlet of the electric motor. The pump chamber is located between the bottom plate of the lower cover and the bottom of the electric motor, and connects the pump chamber and the fuel inlet of the electric motor. What is claimed is: 1. An electric fuel pump for a vehicle, comprising: a pump casing plate that has a communicating path and constitutes an upper surface of a pump chamber; and an impeller that is disposed within the pump chamber and is fixed to the output shaft.