JP2015055201A - Electric pump unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric pump unit having a lid which improves heat radiation performance while having a structure that prevents high pressure water and static electricity from directly intruding into the electric pump unit from a hole part.SOLUTION: An electric pump unit includes an electric motor 3, an oil pump 2, a controller 4, and a lid 8. The lid 8 is formed by a metal plate-like portion and includes: through holes 40 which are formed at parts of a plate surface of the lid 8 penetrating through the lid 8; a drawing portion 34 where a portion near the through holes 40 is subjected to drawing to form and arrange the through holes 40 in a direction perpendicular to the plate surface of the lid 8; and a filter 60 disposed in a portion of the lid 8 that is located between the drawing portion 34 and the controller 4 and including a ventilation film that blocks a liquid and allows a gas to pass.

Description

  The present invention relates to an electric pump unit.

  Conventionally, an electric motor housed in the housing, an oil pump disposed on one end side of the housing and driven to rotate by the electric motor adjacent to the axial center direction of the electric motor, and on the other end side of the housing There is known an electric pump unit that includes a controller that controls an electric motor and a lid that covers an opening of a housing on the side where the controller is disposed. The electric pump unit disclosed in Patent Document 1 has an integrated configuration made of synthetic resin in view of miniaturization and cost reduction. Here, the synthetic resin lid is joined to the housing by spin welding. The lid is provided with a hole communicating with the inside and outside of the housing, and is covered with a filter provided with a gas permeable membrane that blocks liquid and allows gas to pass through the hole. This is because the housing repeatedly expands and contracts as the internal temperature rises during operation of the electric pump unit. For this reason, gas is circulated through the hole (so-called respiration of the electric pump unit). Furthermore, the hole portion of the lid is communicated with a path that is bent and extended in order to prevent malfunction of the controller due to static electricity and damage of electronic components mounted on the board.

JP 2013-87636 A

  However, since the lid made of synthetic resin has poor heat dissipation, further improvement is necessary to release the temperature in the electric pump unit to the outside. On the other hand, in order to attach a breathing filter to the lid, it is necessary to provide a hole on the surface of the lid. However, when the through hole is simply formed on the surface of the lid, if the water pressure of the high pressure washing during vehicle washing is applied directly to the filter, the allowable water pressure of the filter will be exceeded, and water will flow into the electric pump unit. Invades the electronic components mounted on the board. In addition, electrostatic radiation directly enters from the hole, causing malfunction of the controller and damage of electronic components mounted on the board. In this way, if a synthetic resin lid is applied, the shape of the hole can be freely communicated, so that it is easy to make a structure that prevents high-pressure water and static electricity from directly entering the hole. Has a point.

  The present invention was devised in view of such points, and the problem to be solved by the present invention is to improve heat dissipation while adopting a structure in which high-pressure water and static electricity do not enter directly from the hole. An electric pump unit having a lid that can be used.

In order to solve the above problems, the electric pump unit of the present invention takes the following means.
First, an electric pump unit according to a first aspect of the present invention is an electric motor housed in a housing, and is disposed on one end side of the housing and is driven to rotate to the electric motor adjacent to the axial direction of the electric motor. An oil pump, a controller that is disposed on the other end of the housing and controls the electric motor, and an electric pump unit that covers an opening of the housing on the side where the controller is disposed The lid is formed of a metal plate-like portion, and a through-hole formed in a part of the plate surface of the lid with an area relatively smaller than the area of the opening of the housing; By drawing the vicinity of the through hole, the throttle part is formed in a direction in which the through hole intersects the plate surface of the lid, and between the throttle part of the lid and the controller. Is disposed at the site, the liquid is shut off gas is characterized by having a filter having a gas permeable membrane to pass.

  According to the first aspect of the invention, the lid is formed of a metal plate-like portion, and has better heat dissipation than a synthetic resin lid. A part of the plate surface of the metal lid has a through hole formed so as to penetrate in an area relatively smaller than the area of the opening of the housing. Therefore, gas can be circulated through the through hole. In addition, by drawing the vicinity of the through hole, there is a drawn portion where the through hole is arranged and formed in a direction intersecting the plate surface of the lid. Thereby, the through-hole has a structure in which high-pressure water and static electricity do not directly enter. Therefore, it can be set as the electric pump unit which has a lid | cover which can aim at the improvement of heat dissipation, setting it as the structure where high-pressure water and static electricity do not permeate directly from a hole.

  Next, the electric pump unit according to a second aspect of the present invention is the electric pump unit according to the first aspect described above, wherein the through hole is crushed from a direction in which the throttle part intersects the plate surface of the lid, The arrangement is characterized in that the outer side of the housing does not communicate with a straight line.

  According to the second invention, the through hole is crushed from the direction in which the throttle portion intersects the plate surface of the lid, so that the filter and the outside of the housing do not communicate with each other in a straight line. Therefore, it can be set as the lid | cover made into the structure where much more high-pressure water and static electricity do not permeate directly.

  Next, the electric pump unit according to a third aspect of the present invention is the radial pump according to the first aspect or the second aspect, wherein the lid is sealed between the inner peripheral surface or the outer peripheral surface of the opening of the housing. An annular seal member in which a seal portion and an axial seal portion that seals between the axial end portions of the opening portion of the housing are integrally formed is provided.

  According to the third aspect of the invention, the waterproofness can be further improved by providing the lid with the annular sealing member.

  Next, the electric pump unit according to a fourth aspect of the present invention is the electric pump unit according to the third aspect described above, wherein the outer peripheral edge of the axial seal portion protrudes toward the radially outer end surface of the axial end portion. An auxiliary lip is provided.

  According to the fourth aspect of the present invention, the outer peripheral edge portion of the axial seal portion is provided with the auxiliary lip that protrudes toward the radially outer end surface at the axial end portion. Thereby, an axial seal part comprises a labyrinth structure between end surfaces, and can aim at the improvement of waterproofing further.

  Next, an electric pump unit according to a fifth aspect of the present invention is the electric pump unit according to the third or fourth aspect described above, further toward the axial seal portion than the end surface on the radially inner side of the axial end portion. And a convex portion that bites into the axial seal portion.

  According to the fifth aspect of the invention, on the radially inward side at the axial end portion, the convex portion that protrudes further toward the axial seal portion from the end surface and bites into the axial seal portion is provided, so that the sealing performance is further improved. Improvements can be made.

  By taking the measures of the above inventions, the present invention can provide an electric pump unit having a lid that can improve heat dissipation while having a structure in which high-pressure water and static electricity do not enter directly from the hole.

It is a fragmentary sectional view along the axial direction which shows the principal part of the electric pump unit which concerns on this embodiment. It is the expanded sectional view which expanded the II section of FIG. It is the expanded sectional view which expanded the III section of FIG. (A) The figure is the top view which showed the state before shaping | molding of the lid | cover of the electric pump unit which concerns on this embodiment. FIG. 4B is a sectional view taken along line IVB-IVB in FIG. (A) The figure is a fragmentary sectional view showing the restricting part of the lid of the electric pump unit concerning this embodiment. FIG. 5B is a partial cross-sectional view showing a form in which the throttle part is crushed from the direction intersecting the plate surface of the lid.

  An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a partial cross-sectional view along the axial direction showing the main part of the electric pump unit according to the present embodiment. In the following description, the upper left side of FIG. 1 is the front, and the upper right side of FIG. 1 is the rear. That is, the front side is one end side of the housing 1 and the rear side is the other end side of the housing 1.

  As shown in FIG. 1, the electric pump unit is used as a transmission hydraulic pump for an automobile, and includes an electric motor 3 housed in the housing 1 and an axial direction of the electric motor 3 disposed on one end side of the housing 1. An oil pump 2 that is rotationally driven by the electric motor 3 adjacent to the controller 1, a controller 4 that is disposed on the other end side of the housing 1 and controls the electric motor 3, and an opening of the housing 1 on the side where the controller 4 is disposed The lid 8 covering the part is unitized (integrated). As shown in FIG. 1, the electric motor 3 is a brushless motor having three-phase windings.

  The housing 1 includes a waterproof housing including a pump housing 5, a pump plate 6, and a motor housing 7. The pump plate 6 and the pump housing 5 are made of a nonmagnetic material (for example, aluminum die casting). The motor housing 7 is made of a synthetic resin material (thermoplastic resin, for example, reinforced polyamide).

  The pump housing 5 is formed in a pressure plate shape having a spread in a direction orthogonal to the front-rear direction (a direction orthogonal to the axial direction of the housing 1). At its center, a pump chamber 10 having an open front is formed. A pump plate 6 is fixed to the front surface of the pump housing 5 (the end portion on the side where the pump chamber 10 is formed) via an O-ring 11, and the front surface of the pump chamber 10 is closed. An oil pump 2 including an outer gear 12 and an inner gear 13 is disposed in the pump chamber 10. Although not shown, the pump plate 6 is provided with import and outports.

  The oil pump 2 (internal gear pump) uses a trochoid curved pump here, and an inner gear for a pump having external teeth on the inner peripheral side of an outer gear 12 for pumps having an internal tooth having a trochoidal tooth profile. 13, the outer gear 12 and the inner gear 13 are eccentrically disposed in the pump chamber 10 of the pump housing 5 so as to be rotatable. The inner gear 13 is externally fitted and fixed to the front end of the rotary drive shaft 16 opposite to the portion where the rotor 20 is disposed, and rotates together with the rotary drive shaft 16. The outer gear 12 has one more internal tooth than the outer gear of the inner gear 13 and is disposed so as to be rotatable in the pump housing 5 around a position eccentric with respect to the rotary drive shaft 16. The inner gear 13 rotates with its outer teeth meshing with the inner teeth of the outer gear 12 at a part of its entire circumference, and each outer tooth being inscribed in the inner surface of the outer gear 12 at various locations around the entire circumference. ing. Accordingly, when the rotary drive shaft 16 is rotationally driven by the electric motor 3, the volume of the gap between the outer gear 12 and the inner gear 13 of the oil pump 2 repeatedly expands and contracts during one rotation of the rotary drive shaft 16. A pump operation is performed in which oil is sent from an import (not shown) provided in the pump plate 6 leading to these gaps to the outport.

  The motor housing 7 is formed of a synthetic resin in a cylindrical shape, and the front end side thereof is fixed to a portion near the outer periphery of the rear surface of the pump housing 5 via an O-ring 14. The rear end side of the motor housing 7 is closed with a lid 8.

  A cylindrical portion 5a having a smaller diameter than the inner peripheral surface of the motor housing 7 is integrally formed at the center of the rear end surface of the pump housing 5, and is driven to rotate in the front-rear direction by a bearing device 15 provided at the rear portion in the cylindrical portion 5a. The shaft 16 is cantilevered. Here, the bearing device 15 includes ball bearings that are two rolling bearings adjacent to each other in the front-rear direction, the inner ring 15a of each bearing device 15 is fixed to the rotary drive shaft 16, and the outer ring 15b is an inner peripheral surface of the cylindrical portion 5a. It is fixed to. The front portion of the rotary drive shaft 16 passes through a hole 18 formed in the rear wall of the pump housing 5 and enters the pump chamber 10, and the front end thereof is connected to the inner gear 13. A seal 19 is provided between a portion of the cylindrical portion 5 a in front of the bearing device 15 and the rotary drive shaft 16.

  A rotor 20 for a motor constituting the electric motor 3 is fixed to a rear end portion of the rotary drive shaft 16 protruding rearward from the cylindrical portion 5a. The rotor 20 has a cylindrical shape extending in the radial direction from the rear end of the rotary drive shaft 16 and surrounding the outer periphery of the bearing device 15 and the cylindrical portion 5a, and a plurality of permanent magnets 21 extend along the circumferential direction on the outer periphery. They are arranged side by side. A motor stator 22 constituting the electric motor 3 is fixedly provided on the inner periphery of the motor housing 7 facing the rotor 20. In the stator 22, a plurality of inward salient poles of the stator core 23 are arranged on the outside of the outer peripheral surface of the rotor 20 through a slight air gap. A coil 25 is wound around each salient pole of the stator core 23. Here, an insulator (not shown) for insulating the coil 25 from the stator core 23 is mounted from both axial ends of the stator core 23. The stator 22 is formed integrally with the motor housing 7 made of synthetic resin. For example, the stator 22 is formed integrally with the motor housing 7 by insert molding.

  A substrate 26 of the controller 4 is fixed to the rear end side of the motor housing 7. The controller 4 is configured to control the electric motor 3. An inverter circuit that converts a direct current power source into alternating current and supplies a drive current to each coil 25 of the electric motor 3 is mounted on the substrate 26. On the front surface of the substrate 26, electronic components 27 such as coils and capacitors of the above-described circuit constituting the controller 4 are mounted. With the above configuration, the drive current controlled by the substrate 26 is supplied to each coil 25 of the electric motor 3. Thereby, a rotating magnetic field is generated in the coil 25, torque is generated in the permanent magnet 21, and the rotor 20 is rotationally driven. In this way, when the inner gear 13 is driven to rotate, the outer gear 12 is driven and rotated, and the gap between the inner teeth of the outer gear 12 and the outer teeth of the inner gear 13 is repeatedly expanded and contracted. Pump operation is performed to suck and discharge oil through the port.

The lid | cover 8 is comprised by the metal plate-shaped site | parts as shown in FIGS. The material of the lid 8 is preferably a stainless steel material (for example, SUS304) in view of heat dissipation and corrosion resistance. Further, a steel plate material or the like may be subjected to plating after press working. For example, a cold rolled steel plate (SPC material) can be applied. An aluminum alloy or the like can also be applied.
The lid 8 includes a first flat portion 30, a bent portion 31, an insertion tube portion 32, a throttle portion 34, a through hole 40, and a seal member 42. The first plane portion 30 is formed in a disk shape having a diameter substantially the same as the outer diameter of the motor housing 7 on the controller 4 side. The bent portion 31 is folded from the outer periphery of the first plane portion 30 toward the radially inward side and is formed in an annular shape substantially parallel to the first plane portion 30. The insertion tube portion 32 is formed in a cylindrical shape that is bent from the inner diameter side end portion of the bent portion 31 and protrudes in the axial direction on the inner periphery of the opening 7 a on the controller 4 side of the motor housing 7. The throttle part 34 is formed such that a part of the substantially central portion of the first plane part 30 protrudes in the axial direction. The through hole 40 is formed on the outer peripheral surface of the throttle part 34. The seal member 42 is formed in an annular shape having a substantially L-shaped cross section in a range where the elastic member extends from the outer peripheral side of the insertion tube portion 32 to the bent portion 31.

A method for forming the lid 8 will be described.
As shown in FIGS. 4 and 5, first, a part of the metal disk-shaped disk-shaped material 52 has an area relatively smaller than the area of the opening 7 a on the controller 4 side of the motor housing 7 of the housing 1. A through-hole 40 to be formed is formed. After that, the metal disk-shaped member is pressed to form the first flat portion 30, the bent portion 31, and the insertion cylinder portion 32 (see FIG. 1). Next, in the vicinity of the through hole 40, a drawing portion 34 is provided by a well-known drawing process using a punch, a die, and a pressing member. The throttle part 34 has a second plane part 36 that is substantially parallel to the first plane part 30, and a side part 38 that is bent in a direction that intersects the first plane part 30. The through hole 40 is provided in the side surface portion 38 by drawing. Then, the throttle part 34 is processed so as to be crushed in a direction in which the throttle part 34 intersects the first plane part 30 of the lid 8 (a direction in which the first plane part 30 and the second plane part 36 are close to each other). Accordingly, the side surface portion 38 of the throttle part 34 is inclined so as to cover the first flat surface portion 30. As shown in FIGS. 1 and 3, a filter 60 is covered in a portion of the lid 8 between the throttle portion 34 and the controller 4. The filter 60 includes a gas permeable membrane that blocks liquid and allows gas to pass through. As described above, the through hole 40 is configured such that the filter 60 and the outside of the housing 1 do not communicate with each other in a straight line.

  As shown in FIG. 2, the seal member 42 is integrally provided with an elastic member such as rubber over the bent portion 31 of the lid 8 and the insertion tube portion 32 by vulcanization molding. The seal member 42 seals between a radial seal 44 that seals between the inner peripheral surface of the opening 7 a of the motor housing 7 (housing 1) and an axial end 7 b of the opening 7 a of the motor housing 7. The axial seal portion 46 is integrally provided with a substantially L-shaped cross section. The radial seal portion 44 is provided so as to cover the outer peripheral surface of the insertion tube portion 32 in the lid 8. The radial seal portion 44 is formed to have a diameter slightly larger than the inner diameter of the opening 7 a of the motor housing 7. Therefore, the radial seal portion 44 is press-fitted and inserted into the opening 7 a of the motor housing 7. As a result, the radial seal portion 44 seals the opening 7 a of the motor housing 7 in the radial direction. The axial seal portion 46 is provided in an annular shape adjacent to the bent portion 31 in the lid 8, and comes into contact with the axial end portion 7 b of the opening portion 7 a of the motor housing 7, thereby opening the opening portion 7 a of the motor housing 7. Seal in the axial direction. Further, the outer peripheral edge portion of the axial seal portion 46 protrudes toward the radially outer end surface 7c of the axial end portion 7b of the opening 7a of the motor housing 7, and is sealed by coming into contact with the end surface 7c. An auxiliary lip 48 is provided. Accordingly, the axial seal portion 46 has the auxiliary lip 48 to constitute a labyrinth structure. Further, on the radially inner side of the end surface 7c in the axial end portion 7b of the opening 7a of the motor housing 7, a convex portion 7d that protrudes further toward the axial seal portion 46 than the end surface 7c is provided. The convex part 7d is intended to improve the sealing performance by biting into the axial seal part 46.

Thus, according to the electric pump unit according to the present embodiment, the lid 8 is composed of a metal plate-like portion, and has better heat dissipation than a synthetic resin lid. A part of the plate surface of the metal lid 8 has a through-hole 40 formed so as to penetrate in a relatively smaller area than the area of the opening 7a on the controller 4 side of the motor housing 7 of the housing 1. . Therefore, gas can be circulated through the through hole 40. In addition, there is a drawn portion 34 in which the through hole 40 is arranged and formed in a direction intersecting the plate surface of the lid 8 by drawing the vicinity of the through hole 40. Thereby, the through-hole 40 has a structure in which high-pressure water and static electricity do not directly enter. Therefore, it can be set as the electric pump unit which has the lid | cover 8 which can aim at the improvement of heat dissipation, setting it as the structure where high-pressure water and static electricity do not permeate directly from a hole.
Further, the through hole 40 is crushed from the direction in which the throttle portion 34 intersects the plate surface of the lid 8, so that the filter 60 and the outer side of the housing 1 are not arranged in a straight line. Therefore, it can be set as the lid | cover 8 made into the structure where much more high-pressure water and static electricity do not permeate directly. In addition, by providing the lid 8 with the annular seal member 42, the waterproof property can be further improved.
Further, an auxiliary lip 48 is provided at the outer peripheral edge of the axial seal portion 46 so as to protrude toward the end surface 7c on the radially outer side of the axial end portion 7b. Thereby, the axial seal part 46 comprises a labyrinth structure between the end surfaces 7c, and can further improve waterproofness.
Further, on the radially inner side of the axial end portion 7b, a convex portion 7d that protrudes further toward the axial seal portion 46 from the end surface 7c and that bites into the axial seal portion 46 is provided, thereby further improving the sealing performance. It can be planned.

  As mentioned above, although embodiment of this invention was described, the electric pump unit of this invention is not limited to this embodiment, It can implement with other various forms. For example, the radial seal portion of the seal member may seal between the outer peripheral surface of the opening of the housing. Further, the number of through holes provided in the lid is not particularly limited. Any number may be used as long as high pressure water and static electricity do not enter directly.

  Moreover, although the case where the internal gear type pump was used as an oil pump was shown in the said embodiment, not only this but the rotary pump using a vane drive, an external gear, etc. may be sufficient. Further, as an internal gear pump, an inner tooth is provided on the inner peripheral side of the outer gear, and the gap is partitioned by an inscribed portion between the outer gear and the inner gear by rotating eccentrically while meshing with the inner gear having the outer teeth. As long as the volume of the internal gear pump repeats the expansion / contraction change, it is not necessarily limited to the trochoid curve type pump as described above. Further, the inner teeth of the outer gear and the outer teeth of the inner gear are not necessarily formed in a clear so-called tooth shape, and may be protrusions, protrusions, or engaging portions. In the above embodiment, the case where a plurality of permanent magnets are arranged and fixed on the outer peripheral portion of the rotor of the electric motor has been described. However, a ring-shaped permanent magnet may be used.

DESCRIPTION OF SYMBOLS 1 Housing 2 Oil pump 3 Electric motor 4 Controller 5 Pump housing 5a Cylindrical part 6 Pump plate 7 Motor housing 7a Opening part 7b Axial end part 7c End surface 7d Convex part 8 Cover 10 Pump chamber 11 O ring 12 Outer gear 13 Inner gear 14 Seal 15 Bearing device 15a Inner ring 15b Outer ring 16 Rotation drive shaft 19 Seal 20 Rotor 21 Permanent magnet 22 Stator 23 Stator core 25 Coil 26 Substrate 30 First plane part 31 Bent part 32 Insertion cylinder part 34 Restriction part 36 Second plane part 38 Side part 40 Through-hole 42 Seal member 44 Radial seal portion 46 Axial seal portion 48 Auxiliary lip 52 Disc-shaped material 60 Filter

Claims (5)

An electric motor housed in the housing;
An oil pump disposed on one end side of the housing and driven to rotate by the electric motor adjacent to the axial direction of the electric motor;
A controller disposed on the other end of the housing and controlling the electric motor;
An electric pump unit having a lid that covers the opening of the housing on the side where the controller is disposed,
The lid is composed of a metal plate-shaped part,
A through hole formed in a part of the plate surface of the lid with an area relatively smaller than the area of the opening of the housing;
A drawing part where the through hole is arranged in the direction intersecting the plate surface of the lid by drawing the vicinity of the through hole; and
A filter provided with a gas permeable membrane that is disposed at a position between the throttle portion and the controller in the lid, and blocks liquid and allows gas to pass;
An electric pump unit comprising: The electric pump unit according to claim 1,
The through-hole is configured so that the filter and the outer side of the housing do not communicate in a straight line by being crushed from a direction in which the throttle portion intersects the plate surface of the lid. unit. The electric pump unit according to claim 1 or 2,
The lid includes a radial seal portion that seals between the inner peripheral surface or the outer peripheral surface of the opening portion of the housing and an axial seal portion that seals between the axial ends of the opening portion of the housing. An electrically operated pump unit is provided with an annular seal member formed in a conventional manner. The electric pump unit according to claim 3,
An electric pump unit characterized in that an auxiliary lip is provided on the outer peripheral edge of the axial seal portion so as to protrude toward the end surface on the radially outer side of the axial end portion. The electric pump unit according to claim 3 or claim 4,
An electric pump unit characterized in that a projecting portion that protrudes further toward the axial seal portion from the end surface and bites into the axial seal portion is provided on the radially inner side of the axial end portion.

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