JP2000208225A - Commutator and fuel pump therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a commutator reducing in the number of part items and manufacturing man-hours and a fuel pump using it. SOLUTION: This commutator 50 has eight slide members 51 electrically insulated by grooves 65, and supporting members 60 which fix and support the sliding members 51. The sliding members 51 have sliding parts 52 which slide with brushes, and nails 53 projecting outwardly from the sliding parts 52. The nails 53 have a recess 54 to hang armature windings easily. The nails 53 are formed to increase mechanical strength by adding an additional material to a carbon material. Since the nails 53 of the sliding members 51 and the windings 59 are electrically connected, metal terminal members to connect the sliding members 51 and the windings 59 are not necessary. Therefore, the number of part items is reduced and connecting process of the sliding members 51 and the terminal members together with welding materials like solder can be omitted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a commutator in which a sliding member that slides with a brush is formed of carbon, and a fuel pump using the same.

[0002]

2. Description of the Related Art Conventionally, as disclosed in U.S. Pat. No. 5,175,463 and drawings, a sliding member that slides with a brush is formed of carbon, thereby providing the sliding member with corrosion resistance and resistance. A commutator that improves abrasion is known. The commutator is formed, for example, in a disk shape from a plurality of segments, and adjacent segments are electrically insulated from each other by grooves. Each segment is composed of a sliding member and a metal terminal member that is electrically connected to the sliding member by a connecting member such as a brazing pair. The terminal member is electrically connected to the winding of the armature by fusing or the like. The plurality of segments are fixed by a resin material.

[0003]

In the commutator having the above-described structure, a metal terminal member for electrically connecting the sliding member and the winding of the armature is required. A step of connecting the terminal member with a brazing material such as solder is required. Therefore, the number of parts increases and the number of manufacturing steps increases. An object of the present invention is to provide a commutator that reduces the number of parts and the number of manufacturing steps, and a fuel pump using the same.

[0004]

According to the commutator of the present invention, since the winding of the armature and the sliding member made of carbon are electrically connected directly, the terminal made of metal is used. The number of parts is reduced as compared with a commutator in which the sliding member and the armature winding are electrically connected via the member. Further, since the step of electrically connecting the sliding member and the terminal member using a brazing material such as solder can be omitted, the number of manufacturing steps is reduced.

[0005] According to the commutator according to claim 2 of the present invention,
Since the coupling portion has the concave portion, the winding can be easily wound around the coupling portion. According to the commutator of the third aspect of the present invention, since the supporting member supports the connecting portion of the sliding member on which the winding is applied, even if a force is applied to the connecting portion when the winding is applied, the connecting portion. Damage can be prevented.

According to a commutator according to a fourth aspect of the present invention,
The mechanical strength of the connecting part is increased more than the sliding part of the sliding member with the brush. In the sliding part, wear resistance and corrosion resistance are improved by using carbon material,
The contact resistance with the brush is reduced. On the other hand, in the joint portion, metal powder or a binder is added to the carbon material to increase the mechanical strength, thereby preventing the joint portion from being damaged.

According to the fuel pump of the present invention, since the carbon sliding member of the commutator and the armature winding are electrically connected directly, the number of parts of the fuel pump is reduced. And the number of manufacturing steps is reduced.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention; (First Embodiment) FIG. 2 shows a fuel pump according to a first embodiment of the present invention. A fuel pump 10 shown in FIG. 2 is, for example, an in-tank type fuel pump housed in a fuel tank of a vehicle or the like in a fuel supply system of an electronic fuel injection system, and supplies fuel sucked from the fuel tank to an engine side. Things.

The fuel pump 10 comprises a pump section 20 and a motor section 30 as an electromagnetic drive section for driving the pump section 20. The motor section 30 is a DC motor with a brush, and has a configuration in which permanent magnets are annularly arranged in a cylindrical housing 11 and an armature 32 is arranged concentrically on the inner peripheral side of the permanent magnets.

The pump section 20 includes a casing body 21, a casing cover 22, an impeller 23, and the like. Casing body 21 and casing cover 2
2 constitutes one casing member, in which an impeller 23 as a rotating body is rotatably accommodated. Casing body 21 and casing cover 22
Is formed, for example, by die casting of aluminum. The casing body 21 is press-fitted and fixed inside one end of the housing 11, and a bearing 25 is fitted at the center thereof. The casing cover 22 is fixed to one end of the housing 11 by swaging or the like while being covered by the casing main body 21. A thrust bearing 26 is press-fitted and fixed to the center of the casing cover 22. Armature 3
One end of the second rotary shaft 35 is rotatably supported in a radial direction by a bearing 25, and a thrust load is supported by a thrust bearing 26.
The other end of the rotating shaft 35 is rotatably supported by a bearing 27 in a radial direction.

An impeller 2 having a fuel inlet 40 formed in a casing cover 22 and a blade piece formed in a peripheral edge portion.
As the 3 rotates, fuel in a fuel tank (not shown) is drawn into the pump flow path 41 from the fuel suction port 40. The pump flow path 41 is formed in a C shape between the casing body 21 and the casing cover 22 along the outer periphery of the impeller 23. The fuel sucked into the pump passage 41 is pressurized by the rotation of the impeller 23, and is supplied to the fuel chamber 3 of the motor unit 30.
It is pumped to 1.

The armature 32 is rotatably housed in the motor unit 30, and a coil as a winding is housed in the core 32a. The commutator 50 is formed in a disk shape, and is disposed above the armature 32 in FIG. A terminal 46 embedded in the connector 45 from a power supply (not shown)
Electric power is supplied to the coil via a brush and a commutator 50 (not shown). When the armature 32 rotates by the supplied electric power, the impeller 23 rotates together with the rotating shaft 35 of the armature 32. When the impeller 23 rotates, fuel is sucked into the pump flow path 41 from the fuel suction port 40, and the fuel receives kinetic energy from each blade of the impeller 23 and is pumped from the pump flow path 41 to the fuel chamber 31. Fuel chamber 3
The fuel pumped to 1 passes around the armature 32 and is discharged from the fuel discharge port 43 to the outside of the fuel pump. A check valve member 44 is accommodated in the fuel discharge port 43, and the check valve member 44 prevents the fuel discharged from the fuel discharge port 43 from flowing backward.

Next, the configuration of the commutator 50 will be described in detail.
As shown in FIG. 1, the commutator 50 includes eight sliding members 51 divided into eight segments at equal angular intervals, and a support member 60 that fixes and supports the sliding members 51. , Formed in a disk shape. The sliding member 51 has a radial groove 65.
Are electrically insulated from each other.

The sliding member 51 is formed by molding a disk-shaped carbon base material with a resin and then dividing the carbon base material into eight parts. The sliding member 51 includes a sliding portion 5 that slides with the brush.
2 and a claw 53 as a connecting portion protruding to the outer peripheral side of the sliding portion 52. The mechanical strength of the claw 53 and its surroundings is increased more than that of the sliding portion 52 by adding a metal powder, a binder, or the like to the carbon material. Sliding part 52
In order to improve the wear resistance and corrosion resistance and reduce the contact resistance with the brush, a small amount of additive is added to the claws 53. Therefore, the sliding member 51 is formed of a plurality of layers including the sliding portion 52, the claw 53, and the periphery thereof. The claw 53 has a recess 54 so that the winding 59 of the armature 32 can be easily hooked. The winding 59 is hung on the concave portion 54 of the claw 53, and the claw 53 and the winding 59 are electrically connected by a conductive adhesive. The coating of the wire 59 in contact with the claws 53 is removed by dipping in a coating solution or by heating.

The electrical connection between the pawl 53 and the winding 59 may be made after the commutator 50 is assembled to the armature 32. Before the commutator 50 is assembled to the armature 32, the commutator 50
The winding 59 is hung on the pseudo nail by using the pseudo jig of
After removing the covering, the commutator 50 may be attached to the armature 32 and the winding 59 and the claw 53 may be electrically connected.

On the supporting member side of each sliding member 51, a truncated cone-shaped concave portion 55 is formed. The inner diameter of the recess 55 gradually increases from the opening side. When the support member 60 is molded, the recess 55 and the protrusion 61 of the support member 60 are fitted to each other, so that the sliding member 51 is prevented from falling off the support member 60 in the rotation axis direction and the rotation direction of the commutator 50. I do.

The support member 60 is molded from a thermosetting resin such as a phenol resin, and fixes and supports the sliding member 51. The support member 60 has a protruding portion 62 protruding to the outer peripheral side, and the protruding portion 62 supports the claw 53. Since the groove 65 extends from the sliding member 51 to the support member 60, the sliding members 51 are electrically insulated from each other. In FIG. 1, 51a and 60a are grooves 65
2 shows the end surfaces of the sliding member 51 and the supporting member 60 facing.

In the first embodiment, the mechanical strength of the claw 53 is increased by adding an additive to the carbon material. For example, even when a force is applied to the claw 53 when the winding 59 is applied, Damage can be prevented. Sliding member 5
1 is that the sliding portion 52 and the claw 53 may be integrally formed, or a claw 53 having increased mechanical strength by adding an additive material may be integrally formed, and the claw 53 may be inserted into the sliding portion 52. It may be molded.

In the first embodiment, the nail 53 is made of a conductive adhesive.
And the winding 59 are electrically connected.
And may be soldered. In this case, at the time of forming the carbon base material, the claw 53 is formed of a carbon material containing metal powder instead of the carbon material, formed of metal powder instead of the carbon material, or after sintering the carbon base material. It is desirable to fix the metal powder to the claw portion 53 or to perform a plating process to facilitate the soldering of the claw 53 and the winding 59.

(Second Embodiment) FIG. 3 shows a commutator according to a second embodiment of the present invention. The sliding member 71 has a sliding portion 72 that slides on the brush, and a claw 73 as a coupling portion for hanging the winding of the armature. In the second embodiment, the outer peripheral wall 72a of the sliding portion 72 slides with the brush. The claw 73 forms a concave portion 74 on which the winding is applied. The support member 76 fixes and supports the sliding member 71 including the claw 73. The claw 73 and the winding are electrically connected by a conductive adhesive or solder.
A truncated conical recess 75 is formed in the inner peripheral wall of the sliding member 71. The inner diameter of the recess 75 gradually increases from the opening side. When the support member 76 is molded, the concave portion 75 and the protrusion 77 of the support member 76 fit together, so that the sliding member 71 is prevented from falling off the support member 76 in the rotation axis direction and the rotation direction of the commutator 70. I do.

Third Embodiment FIG. 4 shows a commutator according to a third embodiment of the present invention. The sliding member 81 has a sliding portion 82 that slides on the brush, and a claw 83 as a coupling portion for hanging the winding 59 of the armature. The support member 85 fixes and supports the sliding member 81 including the claw 83. The armature winding 59 is hung on the concave portion 84 formed in the claw 83, and the winding 59
And the claws 83 are electrically connected by a conductive adhesive or solder.

The support member 85 forms a claw 86 in the direction of the rotation axis of the claw 83, and the winding 59 is hung on the claw 83 and the claw 86. Even when a tensile force is applied from the armature side to the winding 59 when the winding 59 accommodated in the armature is fixed to the resin, the winding 59 is hung on the claw 86 so that the winding 59 is pulled on the claw 83. Power is not directly applied. Therefore, the nail 83
Damage can be prevented.

In the above-mentioned plurality of embodiments showing the embodiment of the present invention, since the sliding member made of carbon and the winding of the armature are directly electrically connected, the sliding member and the winding are connected. A metal terminal member for electrical connection is not required. Therefore, the number of components can be reduced, and the step of connecting the sliding member and the terminal member with a brazing material such as solder can be omitted. Further, since the claw of the sliding member forms a concave portion for applying a winding, the winding can be easily applied to the sliding member. In addition, since the support member supports the nail, damage to the nail can be prevented even when a force is applied to the nail.

In the above embodiments, a resin material is used as the support member for supporting the sliding member. However, an insulating material other than the resin may be used. Further, in the above-mentioned plural embodiments, the grooves are formed after the resin is filled and divided into the respective sliding members. However, the sliding members are formed in advance, and the sliding members are disc-shaped so that the grooves are formed. And may be filled with resin so that the grooves are not filled.

[Brief description of the drawings]

FIG. 1A is a plan view showing a commutator according to a first embodiment of the present invention viewed from a sliding side with a brush, and FIG. 1B is a cross-sectional view taken along the line BB of FIG. .

FIG. 2 is a sectional view showing a fuel pump according to the first embodiment.

FIG. 3 is a sectional view showing a commutator according to a second embodiment of the present invention.

FIG. 4 is a sectional view showing a commutator according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Fuel pump 50 Commutator 51 Sliding member 52 Sliding part 53 Claw (joining part) 54 Depression 60 Support member 65 Groove 70, 80 Commutator 71, 81 Sliding member 72, 82 Sliding part 73, 83 Claw (joining) Part) 74, 84 Recess 76, 85 Supporting member

Claims (5)

[Claims] 1. A plurality of sliding members made of carbon sliding on a brush and electrically insulated from each other, and a supporting member formed of an insulating material and supporting the plurality of sliding members. A commutator, wherein the sliding member has a coupling portion that is electrically connected directly to a winding of an armature. 2. The commutator according to claim 1, wherein said coupling portion has a concave portion for hanging said winding. 3. The commutator according to claim 1, wherein the support member supports the connecting portion. 4. The commutator according to claim 1, wherein the coupling portion is formed with a mechanical strength greater than that of the sliding portion of the sliding member with the brush. . 5. The commutator according to claim 1, an armature having a winding electrically connected to each sliding member, and driven by rotation of the armature; A fuel pump, comprising: a pump unit that sucks and pumps fuel.