JP2005110478A - Motor and pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor and a pump capable of reducing the number of components and assembling man-hours. <P>SOLUTION: A motor as a motor part 10 of a pump 1 comprises a housing 11, a stator 30 provided to the housing 11, a rotor 20 which has a rotor shaft 21 supported rotatably by the housing 11, a magnet 27 which is provided to the rotor 20 and faces the stator 30, and a thrust bearing 57 which is provided to the housing 11 and pivots one end of the rotor shaft 21 in the thrust direction. The stator 30 and the magnet 27 are provided in such relationship as a magnetic force occurs which energizes the rotor 20 in the direction of the thrust bearing 57 at mutual delivery part of magnetic flux. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a motor and a pump.

Some conventional motors, such as brushless motors, include a housing, a stator, a rotor, a magnet, a thrust bearing, and a spring (see, for example, Patent Document 1). The stator is provided in the housing. The rotor has a shaft that is rotatably supported by the housing. The magnet is provided in the rotor and faces the stator via a predetermined gap. The thrust bearing is provided in the housing and pivotally supports one end of the rotor shaft in the thrust direction. The spring urges the rotor toward the thrust bearing, and one end of the rotor shaft is pressed against the thrust bearing.
JP 2000-102210 A

  In the thing of the said patent document 1, since the spring for urging | biasing a rotor to a thrust bearing direction is required, there existed a problem of causing the increase in a number of parts and an assembly man-hour. This makes it difficult to reduce the size of the motor.

  An object of the present invention is to provide a motor and a pump that can reduce the number of parts and the number of assembly steps.

The above-described problems can be solved by a motor and a pump having the gist of the configuration described in the appended claims.
In other words, according to the motor of the first aspect, the rotor is biased toward the thrust bearing by the magnetic force generated in the magnetic flux transfer portion between the stator and the magnet, so that one end of the rotor shaft is moved to the thrust bearing. Pressed. Therefore, the spring for urging the rotor required in the past in the thrust bearing direction can be omitted, and the number of parts and the number of assembling steps can be reduced.

  According to the motor described in claim 2, the armature is urged in the thrust bearing direction by the magnetic force generated in the magnetic flux receiving portion between the magnet and the armature core. One end is pressed against the thrust bearing. Therefore, the same operation and effect as the motor described in claim 1 of the claims can be achieved.

  Moreover, according to the pump described in Claim 3 of a claim, the pump which shows an effect | action and effect equivalent to the motor described in Claim 1 or 2 of a claim can be provided.

  According to the motor and pump of the present invention, the rotor is urged in the thrust bearing direction by the magnetic force generated in the magnetic flux receiving portion. Therefore, the spring for urging the rotor required in the past in the thrust bearing direction is required. Can be omitted, and the number of parts and assembly man-hours can be reduced.

  Next, the best mode for carrying out the present invention will be described with reference to examples.

A first embodiment of the present invention will be described with reference to the drawings. In this embodiment, a fuel pump for a vehicle in which a brushless DC motor (referred to as a brushless motor) is configured as a motor portion will be exemplified.
In FIG. 1, which shows the fuel pump in a sectional view, the fuel pump 1 is configured to include a motor unit 10 configured by a brushless motor and a pump unit 50 incorporated in a lower portion of the motor unit 10. Yes.

The motor unit 10 will be described. The motor unit 10 includes a housing 11, a rotor 20 that is rotatably supported in the housing 11, and a stator 30 that is fixed in the housing 11.
The housing 11 includes a substantially cylindrical housing cylinder 13, an upper side end cover 15 assembled to the upper end portion of the housing cylinder 13, and a pump casing of the pump section 50 assembled to the lower end portion of the housing cylinder 13. 51 and a pump cover 53. The upper end cover 15 is formed with a substantially concentric shaft support hole 16 on the inner surface side (lower side in FIG. 1), and a substantially cylindrical discharge pipe port 17 penetrating the inside and outside of the cover is eccentric. It is formed at the position.

The rotor 20 includes a rotor shaft 21, a pair of upper and lower stainless steel support members 23 press-fitted relatively to the rotor shaft 21, and a cylindrical electromagnetic stainless steel yoke 25 press-fitted into both the support members 23. And a cylindrical permanent magnet (simply referred to as a magnet) 27 having four magnetic poles in the circumferential direction bonded to the outer periphery of the yoke 25 by a resin adhesive. The magnet 27 is opposed to the stator 30 via a predetermined gap.
Further, the lower end portion of the rotor shaft 21 is rotatably supported by the pump casing 51 via a bearing 28. Further, the upper end portion of the rotor shaft 21 is rotatably supported via a bearing 29 in the shaft support hole 16 of the upper end cover 15. Further, for example, a D-shaped cut portion 21a is formed at the lower end portion of the rotor shaft 21, and the D-shaped cut portion 21a is inserted into a hole of an impeller 59 (described later), for example, a D-shaped hole 59a. Has been. A spherical portion 21b is formed at the tip of the D-shaped cut portion 21a. The spherical portion 21 b is in contact with the upper surface of a thrust bearing 57 provided on the pump cover 53. The upper and lower support members 23 each have a flange portion 23a, and the flange portion 23a is bonded to the end surfaces of the yoke 25 and the magnet 27 with a resin adhesive.

  The stator 30 includes a stator core 31, a resin holder 32 that holds the stator core 31, and a stator coil 33 wound around the stator core 31. The stator 30 is tightly inserted into the housing cylinder 13. Further, the base end portion of the terminal 35 is electrically connected to the terminal portion 33a of the stator coil 33 by fusion welding or the like. The distal end portion (upper end portion in FIG. 1) of the terminal 35 is inserted in a terminal hole 15a formed in the upper side end cover 15 so as to penetrate therethrough, and the control circuit accommodating recess 18 of the upper side end cover 15 is inserted. It protrudes into (described later). A connection board 38 is electrically connected to the tip of the terminal 35. The connection board 38 is supported in the housing recess 18 via a support (not shown).

  The upper end cover 15 is formed with a concave housing recess 18 that opens to the outer end surface (upper end surface in FIG. 1) side thereof. A control circuit 40 for controlling energization to the stator coil 33 of the stator 30 is supported in the housing recess 18 via a support (not shown). The control circuit 40 includes a coil side substrate 41 having a connection terminal 42 and a cover side substrate 43 having an input terminal 44. The tip of the connection terminal 42 of the coil side substrate 41 is electrically connected to the connection substrate 38. Further, the front end portion of the input terminal 44 of the cover-side substrate 43 protrudes from the opening end surface of the housing recess 18 through a cover 46 described later. Although not shown, the control circuit 40 includes, for example, a power MOS-FET that intermittently energizes the U-phase, V-phase, and W-phase of the stator coil 33, and a drive circuit that drives and controls these MOS-FETs. It has. The drive circuit sequentially conducts the FETs with a predetermined overlap time, and excites the stator coil 33 of each phase.

  Further, a cover 46 covering the opening end surface of the housing recess 18 is attached to the upper end cover 15 through attachment means (not shown) such as adhesive, heat caulking, and screw means. A terminal hole 46a is formed in the cover 46, and a distal end portion (upper end portion in FIG. 1) of the input terminal 44 of the control circuit 40 is inserted through the terminal hole 46a.

  Thus, the upper end cover 15 is press-fitted into the housing cylinder 13 so as to be prevented from rotating, and then the upper end portion 13b of the housing cylinder 13 is caulked inward by heat caulking to prevent the upper end cover 15 from coming off. The upper end opening surface of the housing cylinder 13 is sealed. A substantially ring-shaped upper spacer 19 inserted in the housing cylinder 13 is interposed between the opposed surfaces of the upper end cover 15 and the holder 32 of the stator 30.

  Further, the magnet 27 is arranged with a positional relationship shifted by a predetermined amount with respect to the stator 30 in the counter pump portion side direction (upward in FIG. 1). For this reason, in the magnetic flux transfer part between the stator 30 and the magnet 27, a magnetic force that tries to correct the imbalance, that is, a magnetic force that urges the rotor 20 toward the pump portion (downward in FIG. 1) is generated. Thereby, the spherical portion 21 b of the rotor shaft 21 of the rotor 20 is pressed against the thrust bearing 57. For this reason, “fluctuation” due to the rotation of the rotor 20 can be suppressed, and the rotor 20 and the impeller 59 can be stably rotated.

  The magnitude of the magnetic force that biases the rotor 20 can be adjusted by the amount by which the relative position between the stator 30 and the magnet 27 is shifted. Further, the rotor 20 is biased by changing the relative length between the stator 30 and the magnet 27, for example, by extending the upper end of the magnet 27 longer in the anti-pump portion side direction (upward in FIG. 1) than the stator 30. The magnitude of the magnetic force to be adjusted can be adjusted. Further, the amount by which the relative position between the stator 30 and the magnet 27 is shifted and the amount by which the relative length between the stator 30 and the magnet 27 is changed obtain a magnetic force that urges the rotor 20 while securing the rotational force of the rotor 20. It is desirable to set it to a value that can be used.

  Next, the pump unit 50 will be described. As shown in FIG. 1, the pump unit 50 includes a pump casing 51, a pump cover 53, and an impeller 59 that are assembled at the lower end of the motor unit 10. The pump casing 51 is press-fitted into the housing cylinder 13 in a state in which it is prevented from rotating at a predetermined position from its lower opening surface (lower end surface in FIG. 1). The pump cover 53 is press-fitted in a state in which the pump cover 53 is prevented from rotating in the housing cylinder 13 following the pump casing 51. A pump chamber 56 as a regeneration pump is formed between the pump casing 51 and the pump cover 53. Further, after the pump cover 53 is press-fitted, the lower end portion 13a of the housing cylinder 13 is caulked inward by heat caulking to prevent the pump cover 53 from being pulled out while being pressed against the pump casing 51 and the pump chamber. 56 is sealed. The pump cover 53 is formed with a suction port 54 that communicates with the suction side position of the pump chamber 56. Further, the pump casing 51 is formed with a discharge port 52 that communicates with a discharge side position of the pump chamber 56. The pump casing 51 also serves as a lower end cover of the motor unit 10. A substantially ring-shaped lower spacer 39 inserted in the housing cylinder 13 is interposed between the opposing surfaces of the pump casing 51 and the holder 32 of the stator 30.

In the pump casing 51, the lower end portion of the rotor shaft 21 of the rotor 20 is rotatably supported by the bearing 28 as described above.
An impeller 59 of a regenerative pump is rotatably accommodated between the pump casing 51 and the pump cover 53. A hole, for example, a D-shaped hole 59a is formed in the axial center portion of the impeller 59, and the D-shaped cut portion 21a of the rotor shaft 21 of the rotor 20 is inserted into the hole 59a in an engaged state.
Further, a thrust bearing 57 is attached to the shaft center portion on the inner surface side (upper side in FIG. 1) of the pump cover 53 by press fitting. As described above, the spherical portion 21 b of the rotor shaft 21 of the rotor 20 is in contact with the upper end surface of the thrust bearing 57.

Next, the operation of the fuel pump 1 will be described. Although not shown, in actual use, a filter is provided at the suction port 54 of the fuel pump 1, and a fuel supply pipe connected to the fuel injection device of the vehicle is connected to the discharge pipe. The whole is held in the fuel tank by a support means such as an appropriate stay.
That is, when power is applied to the input terminal 44 of the control circuit 40 of the fuel pump 1, the drive circuit in the control circuit 40 sequentially turns on the MOS-FETs with a predetermined overlap time, and the stator coil 33 of each phase is connected. Excited. The rotor 20 rotates by this three-phase half-wave drive. The impeller 59 is rotated following the rotation of the rotor 20, that is, the rotation of the rotor shaft 21, whereby the fuel in the fuel tank is sucked into the pump chamber 56 from the suction port 54, and from the discharge side of the pump chamber 56. It is discharged into the housing 11 through the discharge port 52 of the pump casing 51. The fuel discharged into the housing 11 passes through the gap between the stator 30 and the rotor 20 and is discharged outside the pump through the discharge pipe port 17 of the upper side end cover 15.

  According to the brushless motor as the motor unit 10 incorporated in the fuel pump 1 (see FIG. 1), the rotor is generated by the magnetic force generated in the magnetic flux transfer part between the stator 30 and the magnet 27 as described above. By urging 20 toward the thrust bearing 57 (downward in FIG. 1), one end of the rotor shaft 21 is pressed against the thrust bearing 57. Therefore, a spring for urging the rotor 20 required in the past in the direction of the thrust bearing 57 can be omitted, and the number of parts and the number of assembling steps can be reduced. This is effective in improving the assembling property of the parts accompanying the downsizing of the brushless motor.

Further, since the spring for urging the rotor 20 required in the past in the direction of the thrust bearing 57 is omitted, the generation of loss torque due to the sliding contact of the spring with the rotor shaft 21 can be eliminated.
Further, since the spring does not protrude around the rotor shaft 21, the accommodation space for the arrangement of the spring can be reduced, and the motor unit 10 can be easily downsized.

  Moreover, according to the fuel pump 1 (see FIG. 1) provided with the above-described brushless motor as the motor unit 10, it is possible to provide the fuel pump 1 having the same operation and effect as the above-described brushless motor (motor unit 10). .

  Further, since the stator coil 33 and the terminal 35 of the stator 30 and the control circuit 40 are not exposed to the fuel, it is possible to prevent problems such as short circuit and disconnection due to electrolytic corrosion at these conductive parts.

A second embodiment of the present invention will be described with reference to the drawings. In addition, since a present Example changes a part of said Example 1, the changed part is explained in full detail and the overlapping description is abbreviate | omitted.
As shown in FIG. 2, in this embodiment, a connection board 38 is connected to a terminal 35 in the housing 11 of the fuel pump 1 (see FIG. 1) of the first embodiment. Accordingly, the connection terminal 42 of the coil side substrate 41 is inserted into the terminal hole 15a of the upper side end cover 15 in a penetrating manner, and the tip end portion of the connection terminal 42 is electrically connected to the connection substrate 38. Yes.
Therefore, the second embodiment described above can provide substantially the same operations and effects as the first embodiment.

A third embodiment of the present invention will be described with reference to the drawings. In addition, since a present Example changes a part of said Example 1, the changed part is explained in full detail and the overlapping description is abbreviate | omitted.
As shown in FIG. 3, in this embodiment, in the housing 11 of the fuel pump 1 (see FIG. 1) of the first embodiment, the housing cylinder 13 and the upper end cover 15 are integrally formed as an outer portion 12 by resin integral molding. It has become. The stator 30 in which the terminal 35 is electrically connected to the terminal portion 33a of the stator coil 33 is integrally molded with the outer cylinder 12 by resin molding with respect to the housing cylinder 13. That is, after the stator 30 is set in a resin mold (not shown), the resin mold is filled with a resin material, so that the stator 30 is integrally molded with the outer portion 12 by insert molding. For this reason, the upper side spacer 19 and the lower side spacer 39 in the said Example 1 (refer FIG. 1) are abbreviate | omitted, and a number of parts and an assembly man-hour can be reduced. FIG. 4 is a cross-sectional view showing the stator 30 before insert molding, and the outer shape of the outer portion 12 after resin integral molding is indicated by a dotted line.

Also according to the above-described third embodiment, substantially the same operation and effect as the first embodiment can be obtained.
Furthermore, the stator 30 provided in the housing cylinder 13 is integrally formed with the outer shell 12 including the housing cylinder 13 and the upper end cover 15 by insert molding (see FIG. 5). For this reason, it is not necessary to manufacture the housing cylinder 13 and the upper side end cover 15 as independent parts, and the assembly of the upper side end cover 15 to the housing cylinder 13 is thereby omitted. In addition, since the stator 30 around which the stator coil 33 is wound is insert-molded in the outer shell 12, the assembly of the stator 30 to the outer shell 12 is omitted. Therefore, the assembly of the upper end cover 15 and the stator 30 with respect to the housing cylinder 13 is omitted as compared with the conventional case, so that the number of parts and the number of assembling steps can be reduced. This is effective in improving the assembling property of the parts accompanying the downsizing of the brushless motor.

  Moreover, since the outer shell part 12 is resin-molded, it is advantageous for weight reduction and noise reduction as compared with the case where the outer shell part 12 is made of metal.

  Further, since the control circuit accommodating recess 18 is formed in the outer portion 12, the control circuit 40 for controlling the energization of the stator coil 33 of the stator 30 can be accommodated in the accommodating recess 18.

A fourth embodiment of the present invention will be described with reference to the drawings. In addition, a present Example illustrates instead of the brushless motor of the said Examples 1-3, about the fuel pump 1 for vehicles by which the DC motor was comprised as the motor part 10. FIG. Further, in this embodiment, a direct current motor is configured by changing a part of the first embodiment. Therefore, the changed portion will be described in detail, and a duplicate description will be omitted.
As shown in FIG. 5, in the fuel pump 1 of the present embodiment, an armature 60 is rotatably supported in the housing 11 instead of the rotor 20 in the first embodiment, and a predetermined number is provided on the inner peripheral surface of the housing 11. The magnet 70 is fixed. The magnet 70 is opposed to the armature core 62 of the armature 60 via a predetermined gap.

The armature 60 includes an armature shaft 61, an armature core 62, and a commutator 64. A coil (not shown) is wound around the armature core 62. Similarly to the rotor shaft 21 (see FIG. 1) of the first embodiment, the lower end portion of the armature shaft 61 is rotatably supported by the pump casing 51 via the bearing 28, and the upper end portion of the armature shaft 61 Is supported rotatably via a bearing 29 in the shaft support hole 16 of the upper end cover 15.
Further, similarly to the D-shaped cut portion 21a and the spherical portion 21b (see FIG. 1) of the first embodiment, a D-shaped cut portion 61a and a spherical portion 61b are formed at the lower end portion of the armature shaft 61. . The D-shaped cut portion 61 a is inserted into the D-shaped hole 59 a of the impeller 59, and the spherical portion 61 b is in contact with the upper surface of the thrust bearing 57 provided in the pump cover 53.

  The upper end cover 15 includes a brush 65 that slides on the commutator 64 of the armature 60 and a spring 66 that biases the brush 65 in a direction to press the brush 65 against the commutator 64. A choke coil 67 is conductively connected to the brush 65. The choke coil 67 is electrically connected to an external connection terminal (not shown). A check valve 72 is incorporated in the discharge pipe port 17 of the upper end cover 15. In the first embodiment (see FIG. 1), the control circuit accommodating recess 18, the control circuit 40, the upper spacer 19, the lower spacer 39, the cover 46 and the like of the upper end cover 15 are omitted.

  Thus, the armature core 62 of the armature 60 is disposed with a positional relationship shifted by a predetermined amount in the counter pump portion side direction (upward in FIG. 1) with respect to the magnet 70. For this reason, in the magnetic flux exchange part of the magnet 70 and the armature core 62, the magnetic force which urges | biases the armature 60 to a pump part direction (downward in FIG. 5) generate | occur | produces. Thereby, the spherical portion 61 b of the armature shaft 61 of the armature 60 is pressed against the thrust bearing 57.

  According to the direct-current motor as the motor unit 10 incorporated in the fuel pump 1 (see FIG. 5), as described above, the magnetic force generated in the magnetic flux transfer portion between the magnet 27 and the armature core 62 is used. When the armature 60 is biased toward the thrust bearing 57, one end of the armature shaft 61 is pressed against the thrust bearing 57. Therefore, similarly to the first embodiment, a spring for urging the rotor 20 that is conventionally required in the direction of the thrust bearing 57 can be omitted, and the number of parts and the number of assembling steps can be reduced. This is effective in improving the assembling property of the parts accompanying the downsizing of the brushless motor. This is effective in improving the assembling property of the parts accompanying the downsizing of the DC motor.

  Moreover, according to the above-described fuel pump 1 (see FIG. 5), it is possible to provide the fuel pump 1 that exhibits the same operation and effect as the above-described DC motor (motor unit 10).

  The present invention is not limited to the above-described embodiments, and modifications can be made without departing from the gist of the present invention. For example, the motor of the present invention can be applied as a drive source other than the fuel pump 1. In addition, the outer shell 12 can be integrally formed of a material other than resin. It is also conceivable to omit the control circuit accommodating recess 18 of the upper end cover 15. Further, the pump of the present invention can be used for the fuel pump 1 or a fluid pump such as a water pump. Further, a pump type other than the impeller 59 type can be adopted as the pump unit 50.

It is sectional drawing which shows the fuel pump concerning Example 1 of this invention. It is sectional drawing which shows the fuel pump concerning Example 2 of this invention. It is sectional drawing which shows the fuel pump concerning Example 3 of this invention. It is sectional drawing which shows a stator. It is sectional drawing which shows the fuel pump concerning Example 4 of this invention.

Explanation of symbols

1 Fuel pump 10 Motor part (brushless motor, DC motor)
DESCRIPTION OF SYMBOLS 11 Housing 13 Housing cylinder 20 Rotor 21 Rotor shaft 27 Magnet 30 Stator 31 Stator core 50 Pump part 57 Thrust bearing 60 Armature 61 Armature shaft 62 Armature core 70 Magnet

Claims (3)

A housing;
A stator provided in the housing;
A rotor having a rotor shaft rotatably supported by the housing;
A magnet provided on the rotor and facing the stator;
A thrust bearing provided on the housing and pivotally supporting one end of the rotor shaft in a thrust direction,
The motor according to claim 1, wherein the stator and the magnet are provided with a relationship in which a magnetic force for urging the rotor in the direction of the thrust bearing is generated at a magnetic flux exchange portion between the stator and the magnet. A housing;
A magnet provided in the housing;
An armature having an armature shaft rotatably supported by the housing;
An armature core provided on the armature and facing the magnet;
A thrust bearing provided on the housing and supporting one end of the armature shaft with respect to a thrust direction;
The motor, wherein the magnet and the armature core are provided in such a relationship that a magnetic force for urging the armature in the thrust bearing direction is generated in a magnetic flux exchange portion between the magnet and the armature core. A motor unit constituted by the motor according to claim 1;
A pump unit incorporated in the housing and operated by the motor unit.

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