JP2013230048A - Motor for oil pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor for an oil pump which prevents the deterioration of the sealability with a simple structure.SOLUTION: A motor 1 for an oil pump connects with an oil pump 81 through a connection hole 85 of a housing 82 so as to drive the oil pump 81 for pressurizing a differential oil N accumulated in a differential device 80. The motor 1 for the oil pump comprises: a yoke 2 having a cylindrical part 2b; a bracket 17 covering the one end side of the yoke 2; and a rotation shaft 5 rotatably supported in the yoke 2. The bracket 17 comprises: a fitting part 25 which is provided at a position separated from the rotation shaft 5 to the radial outward side and is formed so as to fit in the connection hole 85; and an inner flange part 26 formed at the differential device 80 side of the fitting part 25 and extending from the fitting part 25 to the radial inward side. A fine space S1 is formed between the inner flange part 26 and the rotation shaft 5.

Description

  The present invention relates to an oil pump motor mounted on a vehicle, for example.

  This type of motor is included in a motor case, and an output portion at one end of the motor passes through a through hole formed in the motor case and protrudes into the engine case. A bearing that is fitted in an annular space between the peripheral surface and the base of the output portion is supported by the motor case, and is fitted in the annular space so as to be juxtaposed with the bearing, and oil from the engine case to the motor case is inserted. There is a motor including an oil seal that seals the flow (see, for example, Patent Document 1).

JP 2009-114905 A

  By the way, in the above-mentioned prior art, in order to make it possible to insert an oil seal into the motor case, high precision is required for processing of the fitting portion. Further, in order to prevent the drive shaft from being worn by the oil seal, it is necessary to quench the sliding surface of the drive shaft with the oil seal. For this reason, there exists a subject that manufacturing cost increases.

Furthermore, there is a problem that assembly work is troublesome, for example, it is necessary to apply oil to the outer periphery of the oil seal in advance in order to smoothly fit the oil seal into the motor case.
Moreover, when the environmental temperature to which the motor is attached becomes high, the aging deterioration of the oil seal is promoted. Further, if the motor is operated many times, the wear of the oil seal is promoted. For this reason, there exists a subject that the sealing performance by an oil seal may fall.

  Here, for example, a motor for driving an oil pump provided to pressurize oil in a portion where oil is stored separately from the engine case, such as the inside of a differential gear, has oil in the motor itself. There is little scattering. Further, since the motor itself is open to the atmosphere, a situation in which oil is sucked into the motor due to the differential pressure hardly occurs.

  In order to ensure the sealing performance of such a motor, if the configuration as in the above-mentioned conventional technology is adopted, not only will it be over-quality and the manufacturing cost will be increased, but also the life that can ensure the sealing performance will be short and the reliability of the motor will be reduced. There is a problem that there is a risk of doing.

  Accordingly, the present invention has been made in view of the above-described circumstances, and provides an oil pump motor that can prevent deterioration in sealing performance with a simple structure.

  In order to solve the above-described problems, an oil pump motor according to the present invention drives a driven body so as to drive a pump provided inside the driven body in order to pressurize oil stored in the driven body. An oil pump motor connected to a pump through a connecting hole of the motor, wherein the yoke has a cylindrical portion, a bracket that covers one end of the yoke, and a rotary shaft that is rotatably supported in the yoke. The bracket is provided at a position spaced radially outward from the rotating shaft and is formed so as to be able to engage with a connecting hole of the driven body, and the covered portion of the engaging portion. And an inner flange portion that is formed on the driving body side and extends radially inward from the engaging portion, and a minute gap is formed between the inner flange portion and the rotating shaft.

  By comprising in this way, the penetration | invasion of the oil inside a motor can be suppressed by an inner flange part, without providing an oil seal conventionally. For this reason, the motor for oil pumps which can prevent a sealing performance fall with a simple structure can be provided.

  The oil pump motor according to the present invention is characterized in that a porous foam is provided between the engaging portion and the rotating shaft.

  By configuring in this way, even if oil enters between the inner flange portion and the rotating shaft, it is possible to suppress the oil from flowing into the motor. Further, since only the porous foam is provided, high accuracy is not required for the processing of the bracket in order to provide this foam. Furthermore, it is not necessary to quench the sliding surface of the rotating shaft with the foam. For this reason, it is possible to reliably prevent an increase in manufacturing cost while reliably preventing a decrease in sealing performance.

  The oil pump motor according to the present invention is provided with a bearing for rotatably supporting the rotary shaft on the opposite side of the driven body from the engagement portion of the bracket, When a holding portion for holding a bearing is formed, an inner diameter of the inner flange portion is L1, an inner diameter of the engaging portion is L2, and an inner diameter of the holding portion is L3, the inner diameter L1, the inner diameter L2, and the inner diameter L3 is set to satisfy L1 <L2 <L3.

With this configuration, it is possible to process the inner diameter of the inner flange portion, the inner diameter of the engaging portion, and the inner diameter of the holding portion at one time from one direction of the bracket, and accurately determine the relative positional relationship of each portion. be able to. Further, the bracket can be easily manufactured, and the manufacturing cost can be reduced.
Further, it becomes possible to assemble the porous foam and the bearing in this order from the opposite side of the bracket to the driven body, and the productivity can be improved.

  According to the present invention, the oil can be prevented from entering the motor by the inner flange portion without providing an oil seal as in the prior art. For this reason, the motor for oil pumps which can prevent a sealing performance fall with a simple structure can be provided.

It is a longitudinal cross-sectional view of the motor for oil pumps in 1st Embodiment of this invention. It is a principal part expanded sectional view of the motor for oil pumps in 2nd Embodiment of this invention.

(First embodiment)
Next, a first embodiment of the present invention will be described with reference to FIG.
FIG. 1 is a longitudinal sectional view of an oil pump motor.
As shown in the figure, an oil pump motor 1 (hereinafter simply referred to as a motor) is for driving an oil pump 81 provided in a differential device 80, and is attached to a housing 82 of the differential device 80. It has been.

  The differential device 80 is provided in a four-wheeled vehicle such as a front engine rear drive (FR) vehicle or a four-wheel drive vehicle, and power generated by the engine is transmitted to a rear wheel (not shown) via a clutch. Configured to communicate. The clutch (not shown) is configured to transmit / release the power generated by the engine to the rear wheels by pumping the differential oil N stored in the housing 82 by driving the oil pump 81. ing.

  The oil pump 81 is disposed in a state where it is immersed in the differential oil N. The drive shaft 84 of the oil pump 81 is connected to the rotating shaft 5 of the motor 1 via the joint member 83.

(Motor for oil pump)
In the motor 1, an armature 3 is rotatably supported in a bottomed cylindrical yoke 2, and a bracket 17 is provided so as to cover the opening 2a of the yoke 2.
The cylindrical portion 2b of the yoke 2 is provided with a plurality of permanent magnets 4 on the inner peripheral surface so that the magnetic poles are in order in the circumferential direction. In addition, a bearing housing 21 that protrudes outward in the axial direction is formed integrally with the bottom 2c of the yoke 2 so as to be rotatably supported on one end of the rotary shaft 5 of the armature 3. Is press-fitted.

  In addition to the rotating shaft 5, the armature 3 includes an armature core 6 that is externally fixed to the rotating shaft 5, an armature coil 7 that is wound around the armature core 6, and the armature core 6 of the rotating shaft 5. And a commutator 13 that is externally fitted and fixed to the bracket 17 side. The armature core 6 is obtained by laminating a plurality of ring-shaped metal plates 8 in the axial direction. A plurality of T-shaped teeth 9 are formed at equal intervals along the circumferential direction on the outer peripheral portion of the metal plate 8.

  By fitting a plurality of metal plates 8 to the rotating shaft 5, dovetail-shaped slots (not shown) are formed between adjacent teeth 9 on the outer periphery of the armature core 6. Each tooth 9 is wound with an enamel-wrapped winding 12 through a slot (not shown), whereby a plurality of armature coils 7 are formed on the outer periphery of the armature core 6.

  A plurality of segments 14 made of a conductive material are provided on the outer peripheral surface of the commutator 13. The segments 14 are made of plate-like metal pieces that are long in the axial direction, and are fixed at equal intervals along the circumferential direction in a state of being insulated from each other. A riser 15 is integrally formed at the end of each segment 14 on the armature core 6 side so as to be folded outward in the radial direction. A terminal portion of the winding 12 is wound around the riser 15, and this terminal portion is fixed by fusing. Thereby, the segment 14 and the armature coil 7 corresponding to this are electrically connected.

Here, an outer flange portion 22 that extends radially outward is integrally formed in the opening 2 a of the yoke 2, and a bracket 17 is attached thereto.
The bracket 17 is formed in a substantially bowl shape, and is arranged with its opening 17a facing the yoke 2 side. And it fixes in the state which the peripheral edge of the opening part 17a of the bracket 17 and the outer flange part 22 of the yoke 2 contact | abutted.

  A holder stay 18 is attached to the inside of the bracket 17. The holder stay 18 is provided with a plurality of brush holders at positions corresponding to the outer peripheral side of the commutator 13, and brushes (all not shown) are provided on the brush holders. The brush is electrically connected to an external power source, and its tip is in sliding contact with the segment 14 of the commutator 13. Thereby, the electric power of the external power supply is supplied to the armature coil 7 via the brush and the commutator 13.

  Further, the bottom portion 17 b of the bracket 17 is formed flat so that the outer surface can come into surface contact with the housing 82 of the differential device 80. A bearing housing 24 for holding a bearing 23 for rotatably supporting the other end of the rotating shaft 5 is integrally formed on the bottom 17b so as to protrude toward the opening 17a.

  The other end of the rotating shaft 5 extends toward the differential device 80 via the bearing 23. A first reduced diameter portion 5a that is reduced in diameter by a step is formed closer to the differential device 80 than the bearing 23 of the rotating shaft 5. Furthermore, a second reduced diameter portion 5b that is reduced in diameter by a step is formed at the tip of the first reduced diameter portion 5a. The tip of the second reduced diameter portion 5 b is connected to the drive shaft 84 of the oil pump 81 via the joint member 83.

Further, a cylindrical inlay portion 25 is integrally formed on the bottom portion 17b of the bracket 17 on the side opposite to the surface on which the bearing housing 24 is formed so as to protrude toward the differential device 80 side. That is, the spigot part 25 is integrally formed in the bottom part 17b in the position corresponding to the 1st diameter reducing part 5a of the rotating shaft 5. FIG.
In other words, the inlay portion 25 is in a state of being disposed at a position spaced radially outward from the first reduced diameter portion 5a of the rotating shaft 5. For this reason, an annular space K <b> 1 is formed between the first reduced diameter portion 5 a and the spigot portion 25.

  On the other hand, the housing 82 of the differential device 80 is formed with a connecting hole 85 penetrating the bearing housing 24 at a portion corresponding to the spigot portion 25. The spigot 25 is engaged with the connecting hole 85 and the motor 1 is attached to the housing 82 by a fixing means such as a bolt (not shown). The inlay engagement is provided with a known sealing means so that the differential oil N does not leak from the connecting hole 85.

Here, an inner flange portion 26 extending inward in the radial direction is integrally formed on the peripheral edge of the inlay portion 25 on the differential device 80 side. That is, the inner flange portion 26 is formed so as to extend from the peripheral edge of the spigot portion 25 toward the first reduced diameter portion 5 a of the rotary shaft 5.
An inner diameter L1 of the inner flange portion 26 is set to be slightly larger than an outer diameter L4 of the first reduced diameter portion 5a of the rotating shaft 5. Thereby, a minute gap S <b> 1 is formed between the first reduced diameter portion 5 a of the rotating shaft 5 and the inner flange portion 26.

When the inner diameter of the spigot portion 25 is L2 and the inner diameter of the bearing housing 24 is L3, the inner diameter L1 of the inner flange portion 26, the inner diameter L2 of the spigot portion 25, and the inner diameter L3 of the bearing housing 24 are:
L1 <L2 <L3 (1)
It is set to satisfy.

With such a configuration, when the inner diameter of the bearing housing 24 and the inner diameter of the spigot portion 25 are processed in the bracket 17, the bracket 17 can be processed at once using a polishing tool (not shown) from the opening 17 a side. it can.
The bearing 23 is press-fitted into the processed bearing housing 24 from the opening 17a side of the bracket 17.

  Further, when the motor 1 is attached to the housing 82 of the differential device 80 and the oil pump 81 is driven, the differential oil N in the housing 82 may be scattered toward the connecting hole 85 of the housing 82. However, the bracket 17 of the motor 1 has an inner flange portion 26 formed in the spigot portion 25, and a minute gap S 1 is formed between the inner flange portion 26 and the first reduced diameter portion 5 a of the rotary shaft 5. It ’s just that. For this reason, it is possible to prevent the differential oil N from entering the motor 1.

(effect)
Therefore, according to the above-described first embodiment, it is possible to suppress the intrusion of the differential oil N into the motor 1 by the inner flange portion 26 without providing an oil seal as in the prior art, and the seal with a simple structure. It is possible to prevent a decrease in sex.
Further, when machining the inner diameter of the bearing housing 24 and the inner diameter of the inlay portion 25 in the bracket 17, the bracket 17 can be machined at once from the opening 17 a side of the bracket 17. The manufacturing cost can be reduced, and the relative positional relationship between the inner flange portion 26, the spigot portion 25, and the bearing housing 24 can be determined with high accuracy.

  In the first embodiment described above, the case where one inner flange portion 26 is integrally formed on the periphery of the inlay portion 25 on the differential device 80 side has been described. However, the present invention is not limited to this, and a plurality of inner flange portions 26 may be formed from the inner peripheral surface of the spigot portion 25. With this configuration, it is possible to further suppress the intrusion of the differential oil N into the motor 1.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG.
FIG. 2 is an enlarged cross-sectional view of a main part of the oil pump motor of the second embodiment. In addition, the same code | symbol is attached | subjected and demonstrated to the same aspect as 1st Embodiment.
In the second embodiment, an oil pump motor 101 (hereinafter simply referred to as a motor) is for driving an oil pump 81 provided in a differential device 80 and is attached to a housing 82 of the differential device 80. The armature 3 is rotatably supported in the bottomed cylindrical yoke 2, and the bracket 17 is provided so as to cover the opening 2 a of the yoke 2. An inlay portion 25 is formed. The inlay portion 25 is inlay-engaged with the connecting hole 85 of the housing 82, and the inner flange portion 26 is integrally formed on the periphery of the inlay portion 25 on the differential device 80 side. The basic configuration is the same as that of the first embodiment described above.

  Here, the difference between the motor 101 of the second embodiment and the motor 1 of the first embodiment is that the bracket 17 of the motor 1 of the first embodiment has a first reduced diameter portion 5a and an inlay portion of the rotating shaft 5. 25, an annular space K1 is formed, and nothing is interposed in the space K1, but in the second embodiment, the felt member 30 is provided in the space K1. . The felt member 30 is formed in a substantially annular shape so as to fill the space K1.

(effect)
Therefore, in the second embodiment described above, in addition to the same effects as those of the first embodiment described above, the felt member 30 is provided in the annular space K1 between the first reduced diameter portion 5a and the spigot portion 25 of the rotating shaft 5. Since it is provided, even if the differential oil N enters from the minute gap S1 between the first reduced diameter portion 5a and the inner flange portion 26 of the spigot portion 25, the differential oil N is absorbed by the felt member 30. Can do. For this reason, the intrusion of the differential oil N into the motor 101 can be reliably suppressed.

  Further, since the felt member 30 is only provided in the space K1, it is not necessary to process the inner peripheral surface of the spigot portion 25 with high accuracy in order to provide the felt member 30 as compared with the case where a conventional oil seal is provided. Furthermore, it is not necessary to quench the first reduced diameter portion 5a of the rotating shaft 5 that becomes a sliding surface with the felt member 30. For this reason, it is possible to reliably prevent an increase in manufacturing cost while reliably preventing a decrease in sealing performance.

  Further, as in the first embodiment described above, the inner diameter L1 of the inner flange portion 26, the inner diameter L2 of the spigot portion 25, and the inner diameter L3 of the bearing housing 24 are set so as to satisfy the expression (1), whereby the bracket It is possible to assemble the felt member 30 and the bearing 23 in this order from one side opposite to the 17 differential device 80. For this reason, the productivity of the motor 101 can be improved.

  In the second embodiment described above, the case where the felt member 30 is provided in the annular space K1 between the first reduced diameter portion 5a and the spigot portion 25 of the rotating shaft 5 has been described. However, the present invention is not limited to this, and it is only necessary that a porous foam capable of absorbing the differential oil N is provided in the space K1. For example, instead of the felt member 30, a sponge member can be used.

The present invention is not limited to the above-described embodiment, and includes various modifications made to the above-described embodiment without departing from the spirit of the present invention.
For example, in the above-described embodiment, the inner flange portion 26 is formed on the bracket 17 of the motor 1 or 101 used for driving the oil pump 81 provided in the differential device 80, or the felt member 30 is provided. Explained the case. However, the present embodiment is not limited to this, and the present embodiment can be applied to a motor for driving an oil pump for various uses.

1,101 Oil pump motor 2 Yoke 2b Tube portion 5 Rotating shaft 17 Bracket 23 Bearing 24 Bearing housing (holding portion)
25 Inlay part (engagement part)
26 Inner flange 30 Felt member (porous foam)
80 differential device (driven body)
81 Oil pump (pump)
85 Connecting hole S1 Minute gap N Differential oil (oil)

Claims (3)

An oil pump motor connected to a pump through a connection hole of a driven body so as to drive a pump provided inside the driven body in order to pressurize oil stored in the driven body,
A yoke having a cylindrical portion;
A bracket that covers one end of the yoke;
A rotation shaft rotatably supported in the yoke,
The bracket is
An engaging portion provided at a position spaced radially outward from the rotating shaft and formed in a connecting hole of the driven body so as to be able to engage in spigot;
An inner flange portion formed on the driven body side of the engagement portion and extending radially inward from the engagement portion;
A motor for an oil pump, wherein a minute gap is formed between the inner flange portion and the rotating shaft.   The oil pump motor according to claim 1, wherein a porous foam is provided between the engaging portion and the rotating shaft. A bearing for rotatably supporting the rotating shaft is provided on the opposite side of the driven body from the engaging portion of the bracket, and a holding portion for holding the bearing is formed on the bracket.
When an inner diameter of the inner flange portion is L1, an inner diameter of the engaging portion is L2, and an inner diameter of the holding portion is L3,
The inner diameter L1, the inner diameter L2, and the inner diameter L3 are:
L1 <L2 <L3
The oil pump motor according to claim 1, wherein the oil pump motor is set so as to satisfy the above.

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