JPH0571436A - Fuel supply apparatus for vehicle - Google Patents

Abstract

PURPOSE:To reduce generation of electric corrosion, bad electrical continuity and failure such as short-circuit or the like in a system where a control circuit for a brushless motor for driving a fuel pump for a vehicle is made one body with a fuel pump and a motor. CONSTITUTION:A pump portion 30, a motor portion 50 and a discharge portion 90 are disposed in a housing 10 of a fuel pump 1. The motor portion comprises a rotor 60 and a stator portion 70, wherein the stator portion is formed like a bottomed cylinder by a resin material 71. A stator coil 73 is molded in the peripheral wall thereof, and a dome-like container 76 storing a control circuit 77 is molded in the wall of the bottom. The resin material completely molds the stator coil, a copper wire from the stator coil, a terminal from the control circuit and a conductive portion such as a terminal for connecting the elements to each other or the like. Thus, the stator coil, the control circuit and the conductive portion between the control circuit and the stator coil are completely kept from being exposed to fuel. Accordingly, the trouble caused by electric corrosion of the conductive portion or the like can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel supply system for a vehicle, wherein a drive motor of a fuel pump is a brushless motor,
In addition, the control circuit of the brushless motor is integrated with the fuel pump and the motor so that it can be installed in the fuel tank of the vehicle.

[0002]

2. Description of the Related Art Conventionally, a vehicle fuel supply device using a brushless motor has been proposed, and a vehicle fuel supply device such as Japanese Utility Model Laid-Open No. 62-59794 is known. In this publication, a control circuit for controlling the excitation of the stator coil is housed in a container, and pressurized gas is sealed in the container to integrate the control circuit in the housing of the fuel pump.

[0003]

In the conventional structure, since the control circuit is isolated from the fuel, it is possible to prevent the control circuit from being defective in conduction due to electrolytic corrosion and short-circuiting the circuit connection. However, in the conventional structure as disclosed in the above publication, since the connection from the control circuit to the stator coil is exposed in the fuel, electrolytic corrosion occurs in the terminal from the control circuit, the connecting copper wire, and the stator coil. However, there is a possibility that a conduction failure may occur or a short circuit may occur.

In view of the above problems, the present invention has a control circuit of a brushless motor for driving a fuel pump integrated with the fuel pump and the motor, and has problems such as occurrence of electrolytic corrosion, poor conduction and short circuit. It was made for the purpose of reducing.

[0005]

In order to achieve the above object, according to the present invention, a rotor to which a permanent magnet is fixed, a plurality of stator coils installed around the rotor, and a stator coil are provided. In a fuel supply device for a vehicle in which a housing controls a control circuit for controlling the energization of the rotor, and a pump unit driven by the rotor, the stator coil, the control circuit, and a conductive portion connecting them. The technical means of covering with a resin material is adopted.

The control circuit may be housed in a container and covered with a resin material. Further, the container that houses the control circuit may be formed in a dome shape. Further, the resin material may form a fuel passage for introducing fuel near the control circuit.

[0007]

According to the structure of the present invention, since the stator coil, the control circuit, and the conductive portion connecting them are covered with the resin material, these portions are not exposed in the fuel, and Electrolytic corrosion in the part of is prevented, conduction failure,
And defects such as short circuits are prevented.

If the control circuit is housed in a container and the container is formed in a dome shape, the container is prevented from being deformed in the molding process by the resin material. Further, if the fuel passage for introducing the fuel is formed in the vicinity of the control circuit, the heat from the control circuit is radiated to the fuel, and the control circuit can be covered with the resin material without degrading the heat dissipation of the control circuit.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a vehicle fuel pump to which the present invention is applied will be described below with reference to FIGS.

FIG. 1 is a sectional view showing the structure of the vehicle fuel pump of the first embodiment, and shows the AA section of FIG. 2 when the vehicle fuel pump of the first embodiment is seen from the discharge port side. In FIG. 1, the cylindrical housing 10 of the vehicle fuel pump 1 is
It has a thinned upper end 11, a thick central portion 12, and a thinned lower end 13. The lower end portion 13 is provided with a pump portion 30, the central portion 12 is provided with a motor portion 50, and the upper end portion 11 is provided with a discharge portion 90.

The pump section 30 includes a pump casing 31.
A pump cover 32 and an impeller 33. The pump casing 31 is fitted into the thick central portion 12 of the housing 10 from the lower end side of the housing 10 without a gap. The pump cover 32 is press-fitted from the lower end side of the housing 10. Pump casing 31 and pump cover 32
Are stopped by the protrusion 14 of the housing 10.

Pump casing 31 and pump cover 32
A pump chamber 34 as a regeneration pump is formed between and. The periphery of the pump chamber 34 is sealed by pressing the pump cover 32 toward the central portion 12 by the caulking portion 15 of the housing 10. A shaft 51 is press-fitted and held in the pump cover 32, and a suction port 35 communicating with the suction side position of the pump chamber 34 is formed. An impeller 33 of the regenerative pump is rotatably housed between the pump casing 31 and the pump cover 32, and the impeller 33 of the regenerative pump is installed on the shaft 51.
Penetrates the impeller 33. Pump casing 31
A discharge port (not shown) that communicates the position of the discharge side of the pump chamber 34 and the inside of the housing 10 is formed therein.

The motor section 50 comprises a rotor 60 rotatably supported by a shaft 51, and a stator section 70 integrally formed of a resin material. The shaft 51 is formed with two groove portions 52 and 53, and each groove portion 52,
A C ring is fitted in 53. The shaft 51 includes three washers and a joint 5 from the groove 52 side.
Four and one washers, a rotor 60, and three washers are inserted and rotatably supported.

The joint 54 has a claw portion 55 inserted into a joint hole 36 formed in the impeller 33, and rotates together with the impeller 33. The joint 54 has another claw portion (not shown) located with the shaft 51 interposed therebetween, and this claw portion is also inserted into another joint hole (not shown) formed in the impeller 33.

The rotor 60 has a cylindrical yoke 61 made of electromagnetic stainless steel. The yoke 61 has a claw portion 62 that is inserted into a joint groove 56 formed in the joint 54, and rotates with the joint 54. In addition, the yoke 6
Reference numeral 1 has another claw portion (not shown) located with the shaft 51 interposed therebetween, and this claw portion is also inserted in another joint groove (not shown) formed in the joint 54. Four ferrite magnets 63 are adhered around the yoke 61 with an epoxy adhesive, and stainless steel plate rings 64 and 65 are press-fitted at both ends thereof. Carbon metals 66 and 67 are press-fitted into the inner peripheral surfaces of both ends of the yoke 61. The ferrite magnet 63 and the plate rings 64 and 65 are molded with PPS resin 68, and the four ferrite magnets 63 are
The space is filled. In order to balance the rotation of the rotor 60, the plate rings 64 and 65 have a diameter of 0.5 to
A 2.0 mm hole is appropriately drilled.

The stator portion 70 is formed of an epoxy resin material 71 containing 20% of glass into a substantially bottomed cylindrical shape. The bottom surface of the housing 10 is located at the upper end side of the housing 10, and the housing 10 is fitted into the central portion 12 of the housing 10 without any gap from the upper end portion 11 side of the housing 10 and is prevented from rotating by a protrusion 16 formed on the housing 10. The stator part 70 has a three-phase stator built in the side wall around the stator part 70 and a control circuit part built in the bottom wall.

The stator has a stator core 72 and a three-phase stator coil 73 wound around the stator core 72, and copper wires at both ends of each phase stator coil extend to the control circuit section.

The control circuit portion is a circular plate 74 made of stainless steel.
And a dome-shaped cover 75 made of stainless steel, and a control circuit 77 is installed in the container 76. The circular plate 74 and the dome-shaped cover 75 may be made of an iron plate plated with nickel. A terminal holder 79 made of resin is provided on the circular plate 74 side of the container 76. The terminal holder 79 holds a power supply terminal 80 and a power supply terminal 81 shown in FIG. And
The resin material 71 covers the terminal holder 79 and the roots of the terminals 80 and 81.

Further, inside the bottom surface of the stator portion 70,
A hole 82 for receiving the shaft 51 is formed. Further, a fuel passage 83 is formed so as to avoid the container 76 from the inside of the bottom surface of the stator portion 70 to the inside of the upper end portion 11 of the housing 10 to the central portion on the outside of the bottom surface of the stator portion 70. As a result, the fuel discharged into the housing 10 by the pump unit 30 passes around the rotor 60,
From the inside of the stator portion 70, the stator portion 70 is pulled out in the radial direction,
It passes between the groove formed in 0 and the housing 10, and flows out to the upper end 11 side of the housing 10.

The fuel passage 83 is formed in a groove shape in the stator portion 70 formed in a cylindrical shape with a bottom. Particularly, on the outer side of the bottom surface of the stator portion 70, the thickness of the resin material 71 covering the container 76 is reduced. ing. Thereby, the circular plate 7 of the container 76
It is possible to efficiently dissipate the heat of the power control element attached to No. 4 to the fuel. Therefore, the temperature rise of the power control element is suppressed, and the motor stop due to the abnormal temperature rise of the power control element can be prevented.

The discharge portion 90 is the upper end portion 1 of the housing 10.
1 has an end cover 91 press-fitted therein. The end cover 91 is pressed toward the central portion 12 of the housing 10 by the caulking portion 17 of the housing 10.
The end cover 91 has a discharge port 93 that communicates with the fuel passage 83 formed in the stator portion 70 and that is provided with a check valve 92. Further, the end cover 91 has a hole 9 through which the relief valve 94 communicating with the fuel passage 83 formed in the stator portion 70 and the terminals 80 and 81 are inserted.
5, 96 are formed. An O-ring is provided in the holes 95 and 96 through which the terminals 80 and 81 are inserted, and a seal is made between the end cover 91 and the resin material 71 that covers the roots of the terminals 80 and 81.

The structure of the stator portion 70 will be described in more detail with reference to FIGS. FIG. 3 shows the structure of the stator portion 70. FIG. 3 is a cross-sectional view of the stator portion 70 before molding, taken along the line BB in FIG. 2, in which the outer shape after molding is indicated by broken lines. FIG. 4 shows FIG.
C of the stator portion 70 after molding, which is indicated by a broken line in FIG.
It is a C cross-sectional arrow view, and shows the gate position at the time of molding.

FIG. 5 is a plan view of the stator portion 70 before molding, as seen from the direction of arrow D in FIG. As shown in FIG. 5, the terminal holder 79 is provided with brass terminals 84a, 84b, 84c, 84d, 84e (hereinafter these are collectively referred to as 84). Also,
The terminal 85 of the control circuit is penetrated through the circular plate 74 of the container 76.
a, 85b, 85c, 85d, 85e (hereinafter, these are collectively referred to as 85) are taken out. Further, the copper wires 86a, 86b, 86c, 8 at both ends of each stator coil are
6d, 86e, and 86f (hereinafter collectively referred to as 86) are drawn out to the periphery of the terminal holder 79. The terminal 84a connects the terminal 81 and the terminal 85a, the terminal 84b connects the terminal 85b and the copper wire 86a, and the terminal 84c connects the terminal 85c.
And the copper wire 86b are connected, and the terminal 84d is the terminal 85.
d and the copper wire 86c are connected, and the terminal 84e connects the terminal 80, the terminal 85e, and the copper wires 86d, 86e, and 86f.

Before molding, the terminals 80 and 81 and the container 76 are held in the terminal holder 79. Further, a stopper portion 87, which extends from the terminal holder 79 so as to avoid the container 76 and has a cylindrical shape,
By contacting the outer circumference of the stator coil 73 and the stator core 72, positioning before molding is performed.
The fuel passage 83 formed at the time of molding with the resin material 71 is formed by penetrating the hole provided in the cylindrical stopper portion 87.

The stator portion positioned by the terminal holder 79 and electrically connected by the terminal 84 is put into a resin mold. In this resin mold, the stator core 72 and the stator coil 7 are
As shown in FIG. 3, a receiving portion 100 protruding into the resin molding die abuts on the stepped portion with 3 and the stator portion is
It is held by the terminals 80 and 81 not resin-molded and the receiving portion 100. The resin inflow gates 101 and 102 to the resin molding die are arranged as shown in FIG.
Two are provided at the right end of the container and are provided at a position far from the container 76. In this resin mold, the resin material 71 is
The stator coil 73, the copper wire 86 of the stator coil, the terminal 84, the terminal 85 and the container 76 are completely covered.

The stator portion 70 is resin-molded in a resin molding die and then centered by cutting the inner diameter and the outer diameter. FIG. 6 is a circuit diagram of the control circuit 77.

The control circuit 77 uses the U phase of the stator coil,
Power MOS- which intermittently energizes V phase and W phase-
FET 77a, 77b, 77c and these MOS-F
Drive circuit 7 for driving and controlling the ETs 77a, 77b, 77c
7d. The drive circuit 77d sequentially turns on each FET with a predetermined overlap time to excite the stator coil of each phase.

Next, the operation of the above embodiment will be described. In actual use, a filter (not shown) is provided at the intake port 35, a pipe (not shown) connected to the fuel injection device of the vehicle is connected to the discharge port 93, and the entire vehicle fuel pump is provided with an appropriate stay. Retained in the fuel tank.

When power is applied to the terminals 80 and 81, the drive circuit 77 causes the MOS-FETs 77a, 77b and 7 to operate.
7c is sequentially turned on for a predetermined overlap time to excite the stator coil of each phase. By this three-phase half-wave drive, the armature 60 rotates and the impeller 33 rotates. Then, due to the rotation of the impeller 33, the fuel is sucked from the suction port 35, passes through the housing 10, and further passes through the fuel passage 83, and is discharged from the discharge port 93.

According to the embodiment described above, the resin material 7
1, the stator coil 73, the copper wire 86 from the stator coil, the container 76 containing the control circuit 77, the terminal 85 from the container 76, and the terminal 84 are all covered and are not exposed to fuel. Therefore, it is possible to reliably prevent problems such as short circuit and disconnection due to electrolytic corrosion in these conductive parts, and to significantly reduce the occurrence of failures.

Further, in the above embodiment, the container 76 accommodating the control circuit 77 is molded with the resin material 71. In molding the resin material 71, usually 100
A molding pressure of up to 150 (Kg / cm2) is used, but in this embodiment, the pressure is adjusted to 30 to 50 (Kg / cm2) in consideration of the pressure resistance of the container 76 against the molding pressure. Further, in order to further withstand this molding pressure, the container 76
The cover 75 was formed in a dome shape. As a result, it is possible to provide the container 76 that is not deformed by the molding pressure during molding,
The container 76 containing the control circuit 77 could be molded with the resin material 71.

Further, in this embodiment, the control circuit 77 that generates heat is cooled by the fuel through the resin material 71 and the container 76. Since the cover 75 of the container 76 is formed in a dome shape, the thickness of the cover 75 can be reduced, and the heat generated from the control circuit 77 can be easily released to the fuel. Particularly, since the thickness of the resin material 71 on the outer side of the circular plate 74 of the container 76 is reduced, the circular plate 74
It is possible to improve heat dissipation from the power control element of the control circuit mounted on the.

Further, the resin inflow gates 101 and 102 are
Since it is provided far from the container 76, the container 76
In the periphery, the molding pressure becomes low due to pressure loss. This also prevents deformation of the container 76 during molding.

Further, according to the above embodiment, the resin material 71 covers the conductive portion and also has a function as a holder for supporting the shaft 51, so that the number of parts can be reduced. In the above embodiment, the cylindrical guide portion 87 extends from the terminal holder 79.
This enables reliable positioning before resin molding.

Next, a second embodiment to which the present invention is applied will be described with reference to FIG. FIG. 7 is a sectional view showing the structure of the vehicle fuel pump according to the second embodiment. Incidentally, components corresponding to the configuration of the first embodiment and having no great difference in function are designated by the same reference numerals, and the description thereof will be omitted.

In the above-described first embodiment, the shaft 51 is fixed, and the rotor 60 is rotatably supported on the shaft 51, but in the second embodiment, the shaft 251 is provided.
Is rotatably supported, and the rotor 26 is attached to the shaft 251.
Fixed to 0.

One end of the shaft 251 is rotatably supported by a bearing 201 provided in the pump casing 231, and the other end thereof is rotatably supported by a centering bearing 202 provided inside the bottom surface of the stator portion 270. To be done.
A groove 20 is formed along the axial direction on the central surface of the shaft 251.
3, the yoke 61 of the rotor 60 is press-fitted therein. Further, the shaft 251 has a D cut portion 20.
4 is formed, and the D-cut portion 204 has the impeller 231.
It is inserted in the D-shaped hole 205 formed in the. Bearing 2
01 is press-fitted into the pump casing 231. The alignment bearing 202 is supported by a receiving portion 206 formed inside the bottom surface of the stator portion 270, and is held by a bearing stopper 207.

In this embodiment, the shaft 251 also rotates together with the rotor 60, and the impeller 233 rotates as the shaft 251 rotates. Then, the fuel is discharged as in the first embodiment.

In the second embodiment as well, as in the first embodiment, all the conductive portions are covered, and the same effect as in the first embodiment can be obtained. Next, a third embodiment to which the present invention is applied will be described with reference to FIG.

FIG. 8 is a sectional view showing the structure of a vehicle fuel pump according to the third embodiment. In addition, components corresponding to the configuration of the second embodiment and having no great difference in function are denoted by the same reference numerals, and description thereof will be omitted.

In the third embodiment, the stator portion 370 is provided with a brass tubular member 301, and a pump casing 331 is provided.
Is equipped with a relief valve 394. The tubular member 301 forms a discharge port 393, and a check valve 392 is provided inside the discharge port 393. Then, when the stator portion 370 is molded with resin, the stator portion 370 is held in a resin molding die and integrally molded with the resin material 71 as a part of the stator portion 370.

The stator portion 370 includes a stator portion 370.
Passage 302 extending from the inside to the outside in the radial direction
A groove portion 303 extending along the thick portion 312 of the housing 310, and a fuel passage 304 extending radially inward from the groove portion 303, and the fuel inside the stator portion 370 forms the fuel passage 302 and the groove portion. It is guided to the discharge port 393 through 303 and the fuel passage 304. For this reason, also in this embodiment, the fuel is introduced to the outside of the circular plate 74 of the container 76, and the resin material 71 in that portion is formed thin, so that the heat from the control circuit 77 in the container 76 is reduced. Dissipates heat well. The stator portion 370 is similar to the end cover 91 of the first embodiment described above in the housing 310.
It is fixed by the caulking portion 17.

A hole 305 from the inside of the housing 310 and a hole 306 from the radial direction are formed in the pump casing 331, and the relief valve 394 is housed in the hole 306. Further, the pump casing 331 has a hole 30
A groove portion 307 is formed from 6 along the housing 310, and a groove portion 308 connected to the groove portion 307 is formed in the pump housing 332. As a result, the fuel released from the relief valve 394 is released to the outside of the housing 310.

In this embodiment, the tubular member 301 is integrated with the stator portion 370 to form the discharge port 301. Therefore, according to this embodiment, the number of parts can be further reduced.

Also in the third embodiment, like the first embodiment, all the conductive parts are covered, and the same effect as in the first embodiment can be obtained. Next, a fourth embodiment to which the present invention is applied will be described with reference to FIGS.

FIG. 9 is a partial sectional view showing the structure of a vehicle fuel pump according to the fourth embodiment. FIG. 9 shows a sectional view of the vehicle fuel pump of the fourth embodiment taken along the line BB in FIG. 10 is a sectional view taken along line EE of FIG. Incidentally, components corresponding to the configuration of the first embodiment and having no great difference in function are designated by the same reference numerals, and the description thereof will be omitted.

In this fourth embodiment, the circular plate 7 of the container 76 is
The resin material 71 covering the outer side of 4 is formed thinner to promote heat dissipation. A groove-shaped fuel passage 83 is formed outside the bottom surface of the stator 70. On the outside of the bottom surface of the stator portion 70, a resin material 71 is used to form a thick portion 71a along the outer periphery of the circular plate 74 and a thin portion 7 corresponding to the central portion of the circular plate 74.
1b are formed. The thin portion 71b further promotes heat dissipation from the control circuit 77 mounted on the circular plate 74. As a result, the temperature rise of the power control element of the control circuit 77 is suppressed, and the motor stop due to the abnormal temperature rise is prevented.

Next, a fifth embodiment to which the present invention is applied is shown in FIG.
1 and FIG. 12 will be described. FIG. 11 is a partial cross-sectional view showing the structure of the vehicle fuel pump according to the fifth embodiment.
Further, FIG. 12 is a sectional view taken along line F-F in FIG. 11. In addition, components corresponding to the configuration of the fourth embodiment and having no great difference in function are denoted by the same reference numerals, and description thereof will be omitted.

In the fifth embodiment, as in the fourth embodiment, the resin material 71 is provided on the outer side of the bottom surface of the stator portion 70, and the thick portion 71a along the outer periphery of the circular plate 74 and the circular plate 7 are formed.
4 and a thin portion 71b corresponding to the central portion of the No. 4 is formed. Furthermore, in the fifth embodiment, three ribs 71c extending from the thick portion 71a are provided. These ribs 71c are formed along the fuel flow in consideration of resistance to the fuel flow in the fuel passage 83. This rib 7
With 1c, sufficient strength can be given to the resin material 71 even when the thin portion 71b is formed on the outer side of the circular plate 74. Therefore, even if the temperature of the circular plate 74 becomes high, it is possible to prevent the resin material 71 from peeling or cracking.

Although a plurality of ribs are formed along the fuel flow direction in the fourth embodiment, one rib or a rib having an appropriate shape is formed in consideration of the strength of the thin portion. May be.

Further, in the above-described embodiments, the circular plate 74 is used.
The thickness of the resin material 71 was reduced to correspond to the central part of
The resin material 71 may be thinly formed in correspondence with the position where the temperature of the circular plate 74 rises most, for example, the position where the power control element is mounted.

[0052]

As described above, according to the present invention, since the stator coil, the control circuit, and the conductive portion connecting them are covered with the resin material, these portions are not exposed in the fuel. It is possible to prevent electrolytic corrosion in these portions, and to prevent defects such as conduction defects and short circuits.

[Brief description of drawings]

FIG. 1 is a sectional view of a vehicle fuel pump according to a first embodiment of the present invention.

FIG. 2 is a top plan view of the vehicle fuel pump of the first embodiment to which the present invention is applied.

FIG. 3 is a cross-sectional view showing a configuration of a stator section.

4 is a cross-sectional view taken along the line CC of FIG.

FIG. 5 is a top plan view of a stator portion.

FIG. 6 is a circuit diagram of a control circuit.

FIG. 7 is a sectional view of a vehicle fuel pump according to a second embodiment of the present invention.

FIG. 8 is a sectional view of a vehicle fuel pump according to a third embodiment of the present invention.

FIG. 9 is a partial sectional view of a vehicle fuel pump according to a fourth embodiment of the present invention.

10 is a cross-sectional view taken along the line EE of FIG.

FIG. 11 is a partial cross-sectional view of a vehicle fuel pump according to a fifth embodiment of the present invention.

12 is a cross-sectional view taken along the line FF of FIG.

[Explanation of symbols]

 1 Vehicle Fuel Pump 10 Housing 30 Pump Section 50 Motor Section 60 Rotor 70 Stator Section 72 Stator Core 73 Stator Coil 76 Container 77 Control Circuit 83 Fuel Passage 79 Terminal Holder 80, 81 Terminal 84 Terminal 85 Terminal 86 Copper Wire 90 Discharge Section

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeru Tanizawa 1-1-1, Showa-cho, Kariya city, Aichi prefecture Nihon Denso Co., Ltd.

Claims (4)

[Claims] 1. A rotor to which a permanent magnet is fixed, a plurality of stator coils installed around the rotor, a control circuit for controlling energization of the stator coils, and a rotor driven by the rotor. A fuel supply device for a vehicle, wherein a pump portion is built in a housing, wherein a conductive portion connecting the stator coil and the control circuit is covered with a resin material. 2. The vehicle according to claim 1, wherein the control circuit is housed in a container, and the container, the stator coil, and the conductive portion are covered with the resin material and integrated. Fuel supply system. 3. The fuel supply device for a vehicle according to claim 2, wherein the container is formed in a dome shape. 4. The fuel supply system for a vehicle according to claim 1, wherein the resin material forms a fuel passage for introducing fuel near the control circuit.