JP6306320B2 - Electric oil pump and hydraulic supply device - Google Patents

Description

  The present invention relates to an electric oil pump and a hydraulic pressure supply device provided, for example, in a transmission of a vehicle.

  Conventionally, for example, an electric oil pump disclosed in Patent Document 1 includes a motor unit and a pump rotor that rotates based on driving of the motor unit in a housing. A part of the housing is inserted into a pump mounting recess provided in the transmission of the vehicle, and the opening of the pump mounting recess is closed by the housing. Further, the housing is formed with a suction port and a discharge port for sucking and discharging oil by rotation of the pump rotor. When the pump rotor is rotated, the oil introduced from the oil introduction passage in the pump mounting recess is taken in from the suction port and led out to the oil outlet passage in the pump mounting recess through the discharge port. ing.

JP 2011-94553 A

  In the electric oil pump as described above, heat is easily generated especially in the stator of the motor unit, and the heat is transmitted to the pump rotor and oil, thereby affecting the pump performance. Therefore, improvement in heat dissipation is desired.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide an electric oil pump and a hydraulic pressure supply device that can improve heat dissipation.

An electric oil pump that solves the above problem includes a motor unit and a pump rotor that rotates based on driving of the motor unit, and a housing having an oil inlet and an outlet, and at least a part of the housing is a pump An assembly mode in which the housing is inserted into the mounting recess and closes the opening of the pump mounting recess by the housing, and the oil introduced from the oil introduction path in the pump mounting recess based on the operation of the pump rotor is sucked in. An electric oil pump that takes in from a port and leads to an oil lead-out path in the pump mounting recess through the discharge port, and is provided between the inner surface of the pump mounting recess and the outer surface of the housing. Based on the operation of the rotor, an oil inflow space is formed through which oil flows in from the oil introduction path. A part of the housing is immersed in oil accumulated in the oil inflow space, and the housing has a check valve for suppressing the backflow of oil from the oil inflow space to the oil introduction path. The housing is provided with a discharge port having the discharge port, and the check valve is provided in a flow channel in the discharge port and in a flow channel portion to the discharge port. The check valve closes the flow path in the discharge port when the pump rotor is not driven, and enables the oil to flow in the discharge port when the pump rotor is driven. open end of said at mouth oil inflow space side, together are disposed in a vertically lower side than the pump rotor, wherein the inlet, and, a in the flow path in the discharge port The flow path portions on the pump rotor side with respect to the check valve respectively communicate with the pump chamber of the pump rotor, and the oil flow path from the oil introduction path to the oil lead-out path is from the upstream side. In order, the oil introduction path, the oil inflow space, the suction port, the pump chamber, the discharge port, and the oil lead-out path, the suction port, and a flow path in the discharge port; Both the flow path portions on the pump rotor side with respect to the check valve communicate with the pump chamber on the lower side in the vertical direction than the rotation shaft of the pump rotor .

  According to this configuration, since a part of the housing is immersed in the oil in the oil inflow space, the heat of the housing (especially the heat of the motor unit) is preferably suitably transmitted through the oil that has a generally higher thermal conductivity than air. It is possible to dissipate heat. In addition, when the pump rotor is stopped, oil flow from the oil inflow space to the oil introduction path is suppressed by the check valve, so that deterioration of heat dissipation due to a decrease in oil in the oil inflow space is suppressed. Can do.

Moreover , it can suppress that air flows in into a housing (site | part which accommodates a pump rotor) from an oil lead-out path via a discharge outlet. Thereby, it can suppress that the internal components in a housing corrode by the water vapor | steam in air.

Further , the opening end (inlet end) of the suction port is provided on the lower side in the vertical direction than the pump rotor. For this reason, the oil level (water level) of the oil in the oil inflow space during operation in a state where no oil is accumulated in the oil inflow space (for example, the first operation after the electric oil pump is assembled in the pump mounting recess) It is possible to shorten the time to reach the suction port. As a result, it is possible to shorten the time for which the pump rotor rotates in the absence of oil, and as a result, it is possible to suppress wear of the pump rotor and to reduce the lifetime.

In the electric oil pump, the housing comprises the discharge port with the discharge port in the distal end portion with axially projecting, the discharge port are preferably fitted to the oil discharge path.

According to this configuration, it is easy to align the discharge port of the electric oil pump and the oil lead-out path, and the assemblability can be improved .

  According to this configuration, since the check valve is provided in the discharge port protruding in the axial direction of the housing, the housing in the pump mounting recess is secured while securing the space for arranging the check valve on the discharge port side of the pump rotor. It is possible to suppress an increase in the axial length (length that does not include a portion inserted into the oil outlet passage). In addition, since a check valve is provided in the discharge port on the discharge side of the pump rotor, air is prevented from flowing into the housing (portion housing the pump rotor) through the discharge port from the oil outlet passage. Can do. Thereby, it can suppress that the internal components in a housing corrode by the water vapor | steam in air.

A hydraulic pressure supply device that solves the above problem includes a pump mounting recess having an oil introduction path and an oil outlet path, and an electric oil pump assembled to the pump mounting recess, and the electric oil pump includes a motor section and the motor. A housing having a pump rotor that rotates based on driving of the portion and having an oil inlet and an outlet, and at least a part of the housing is inserted into the pump mounting recess, and the housing An assembly mode that closes the opening is adopted, and oil introduced into the pump mounting recess from the oil introduction path is passed through the suction port and the discharge port of the housing based on the operation of the pump rotor of the electric oil pump. A hydraulic pressure supply device that is led out from the oil lead-out path, the inner surface of the pump mounting recess and the An oil inflow space into which oil flows in from the oil introduction path is formed between the outer surfaces of the udging based on the operation of the pump rotor, and a part of the housing is immersed in the oil accumulated in the oil inflow space. The housing is provided with a check valve for suppressing the backflow of oil from the oil inflow space to the oil introduction path , and the housing has the discharge port. A discharge port, and the check valve is provided in a flow path in the discharge port and a flow path portion to the discharge port , and the check valve is not driven when the pump rotor is not driven. thereby closing the flow path in the discharge port, when the driving of the pump rotor is one that enables the oil to flow in the discharge port, it said in the inlet oil Open end of the inlet space side, said with are provided in the vertically lower than the pump rotor, said inlet, and a flow path in a to and the pump than the check valve in the discharge port The flow path portions on the rotor side are each in communication with the pump chamber of the pump rotor, and the oil flow path from the oil introduction path to the oil lead-out path is in order from the upstream side, the oil introduction path, the oil An inflow space, the suction port, the pump chamber, the discharge port, and the oil lead-out path, the flow path in the suction port and the discharge port, and the pump rotor rather than the check valve Both of the flow path portions on the side communicate with the pump chamber on the lower side in the vertical direction than the rotation axis of the pump rotor .

  According to this configuration, since a part of the housing is immersed in the oil in the oil inflow space, the heat of the housing (especially the heat of the motor unit) is preferably suitably transmitted through the oil that has a generally higher thermal conductivity than air. It is possible to dissipate heat. In addition, when the pump rotor is stopped, oil flow from the oil inflow space to the oil introduction path is suppressed by the check valve, so that deterioration of heat dissipation due to a decrease in oil in the oil inflow space is suppressed. Can do.

In addition , since the check valve is provided in the housing of the electric oil pump, the degree of freedom in designing the pump mounting recess can be improved.
Moreover, it can suppress that air flows in into a housing (site | part which accommodates a pump rotor) from an oil lead-out path via a discharge outlet. Thereby, it can suppress that the internal components in a housing corrode by the water vapor | steam in air.
Further, the opening end (inlet end) of the suction port is provided on the lower side in the vertical direction than the pump rotor. For this reason, the oil level (water level) of the oil in the oil inflow space during operation in a state where no oil is accumulated in the oil inflow space (for example, the first operation after the electric oil pump is assembled in the pump mounting recess) It is possible to shorten the time to reach the suction port. As a result, it is possible to shorten the time for which the pump rotor rotates in the absence of oil, and as a result, it is possible to suppress wear of the pump rotor and to reduce the lifetime.

  According to the electric oil pump and the hydraulic pressure supply device of the present invention, heat dissipation can be improved.

It is sectional drawing which shows the state which assembled | attached the electric oil pump of embodiment to the transmission. It is a top view of the motor rotor of the same form. It is a schematic diagram for demonstrating the pump rotor of the same form. It is sectional drawing which shows the hydraulic supply apparatus of another example. It is sectional drawing which shows the hydraulic supply apparatus of another example.

Hereinafter, an embodiment of a hydraulic pressure supply device including an electric oil pump will be described.
As shown in FIG. 1, the electric oil pump 10 of this embodiment is used for a transmission 11 (driving force transmission device) mounted on a vehicle, and a pump mounting recess 12 recessed in the transmission 11. The electric oil pump 10 is partly embedded in an embedded manner. The electric oil pump 10 and the pump mounting recess 12 constitute a hydraulic pressure supply device D of the transmission 11.

  The housing 13 of the electric oil pump 10 includes a substantially cylindrical motor case 14, a pump case 15 provided at one end of the motor case 14 in the axial direction (hereinafter referred to as the first end 14 a), and the axial direction of the motor case 14. It is comprised from the circuit case 16 provided in the other end part (henceforth the 2nd end part 14b).

  The motor case 14 is made of a metal material (preferably iron) and is provided so that the central axis L1 thereof is parallel to the horizontal direction. Inside the motor case 14 is housed a motor portion 17 as a drive source for the electric oil pump 10. The motor unit 17 includes an annular motor stator 21 fixed to the inner peripheral surface of the motor case 14, and a motor rotor 22 disposed inside the motor stator 21.

  The motor stator 21 has a stator core 23 made of a plurality of electromagnetic steel plates laminated in the axial direction. The stator core 23 is formed with a plurality of tooth portions 23a extending radially inward, and a coil 24 is wound around each tooth portion 23a. The outer peripheral surface of the stator core 23 is in metal contact with the inner peripheral surface of the motor case 14. Further, the central axis of the motor stator 21 is configured to coincide with the central axis L <b> 1 of the motor case 14. Further, the coil 24 is inserted into a space (slot) formed between the circumferential directions of the tooth portions 23a.

  The motor rotor 22 includes a rotating shaft 25 and a substantially cylindrical rotor core 26 (rotor main body portion) that is externally fixed (press-fit) to the rotating shaft 25. The rotor core 26 is configured by laminating a plurality of electromagnetic steel plates in the axial direction. The rotating shaft 25 is made of stainless steel, which is a nonmagnetic metal, and the axis of the rotating shaft 25 is configured to coincide with the central axis L <b> 1 of the motor case 14.

  As shown in FIG. 2, a plurality of (four in the present embodiment) magnet magnetic pole portions 27 that are radially opposed to the teeth portion 23 a are formed on the outer peripheral portion of the rotor core 26 at equal intervals in the circumferential direction. Each magnet magnetic pole portion 27 is formed by embedding a plate-like magnet 28 in the peripheral portion of the rotor core 26. That is, the motor rotor 22 of the present embodiment is configured as an embedded magnet type (IPM type) motor rotor.

  Specifically, magnet housing holes 26a drilled in the axial direction are provided in the circumferential portion of the rotor core 26 at equal intervals (90-degree intervals) in the circumferential direction, and the radial direction of the rotor core 26 is provided in each magnet housing hole 26a. Each magnet magnetic pole portion 27 is formed by accommodating and fixing each magnet 28 in an orthogonal manner. Each magnet 28 is disposed so that the magnetic pole surface on the radially outer side of the rotor core 26 has the same polarity (for example, S pole). As a result, four magnet magnetic pole portions 27 having the same polarity (S pole) are formed in the motor rotor 22 at substantially equal intervals (approximately 90 ° intervals) along the circumferential direction. Between the circumferential directions of the magnet magnetic pole portions 27, an iron core portion 26b of the rotor core 26 is formed to project outward in the radial direction. A pseudo magnetic pole having a polarity different from that of the adjacent magnet magnetic pole portion 27 is formed in each iron core portion 26 b by the magnetic action of the magnet 28. That is, the motor rotor 22 is configured as a so-called continuous pole type rotor.

  Here, the number of slots of the motor stator 21 (the number of teeth portions 23a) is set to an integral multiple of the number of magnet magnetic pole portions 27. That is, in this embodiment, since the number of the magnet magnetic pole portions 27 is 4, the number of slots of the teeth portion 23a is set to an integral multiple of 4. As a result, when one magnet magnetic pole portion 27 faces one tooth portion 23a, the magnet magnetic pole portion 27 and the tooth portion 23a also face each other at other locations, so that the radial direction applied to the motor rotor 22 can be reduced. Uneven load can be reduced.

  The pump case 15 includes a main body portion 31 assembled to the first end portion 14 a of the motor case 14 and a lid portion 32 assembled to the main body portion 31. Both the main body 31 and the lid 32 are made of an aluminum material that is a nonmagnetic metal. The main body 31 is press-fitted and fixed to the opening of the first end 14 a of the motor case 14. The pump chamber 33 formed inside the main body 31 is liquid-tightly closed by a lid portion 32 assembled from the motor portion 17 side in the direction of the axis L1.

  Further, the pump case 15 has a rotary shaft 25 by a shaft support recess 34 (second shaft support portion) provided in the pump chamber 33 and a shaft support hole 35 (first shaft support portion) formed through the lid portion 32. Is supported. The shaft support hole 35 (lid portion 32) is provided on the motor portion 17 side of the pump chamber 33, and the shaft support recess 34 is provided on the non-motor portion side (discharge port 37 side) of the pump chamber 33. In the pump chamber 33, a pump rotor 36 (pump action part) connected to the rotary shaft 25 is disposed.

  As shown in FIG. 3, the pump rotor 36 is of an inscribed gear type, and is of an inscribed gear type, and has an outer rotor portion 36a having n teeth (n is a natural number of 3 or more) teeth, The inner rotor portion 36b includes n-1 pieces, and one end side of the rotary shaft 25 is fixed to the inner rotor portion 36b.

  Specifically, the inner rotor portion 36b has four external teeth Tb, and the outer rotor portion 36a has five internal teeth (grooves) Ta that mesh with the external teeth Tb. The outer rotor portion 36a rotates by sliding on the inner peripheral surface of the pump chamber 33 around the shaft center Xa deviating from the shaft center Xb of the inner rotor portion 36b (the rotation shaft 25) based on the rotation of the inner rotor portion 36b. It is supposed to be configured.

  In the present embodiment, the inner rotor portion 36b and the outer rotor portion 36a are formed of an engineering plastic that is a resin material having excellent heat resistance, durability, and mechanical properties (wear resistance and impact strength). Further, in order to improve the strength, carbon fiber (or glass fiber) is mixed in the engineering plastic constituting the inner rotor portion 36b and the outer rotor portion 36a. Examples of engineering plastics include polyimide materials and polyamide materials.

  As shown in FIG. 1, the bottom 31 a of the main body 31 of the pump case 15 is exposed to the outside of the motor case 14, and the bottom 31 a has a cylindrical shape protruding along the axial direction of the motor case 14. A discharge port 37 is formed. The inside of the discharge port 37 is in communication with the pump chamber 33. Further, the central axis L2 of the discharge port 37 is shifted from the central axis L1 of the motor case 14. In addition, a check valve 38 is provided inside the discharge port 37 to prevent the flow of oil from an oil outlet passage 41 (described later) to the pump chamber 33.

  The check valve 38 includes a ball 38a and a compression coil spring 38b. The ball 38a is provided so as to be able to close the narrowed portion 37a in the discharge port 37, and the compression coil spring 38b biases the ball 38a toward the narrowed portion 37a. The ball 38a closes the constriction 37a when the pump rotor 36 is not driven, and is separated from the constriction 37a against the spring pressure by the oil pressure when the pump rotor 36 is driven. Allow distribution. The ball 38a and the compression coil spring 38b are preferably made of a heat-resistant material such as metal or resin.

  In addition, a suction port 31 b that connects the space between the pump case 15 and the pump mounting recess 12 (oil inflow space S) and the pump chamber 33 is formed on the outer peripheral portion of the main body 31 of the pump case 15. . The suction port 31b extends vertically downward from the position of the pump chamber 33 (perpendicular to the central axis L1), and is formed to open vertically downward from the outer peripheral surface (lower surface) of the main body 31.

  The second end portion 14b of the motor case 14 is formed with a flange portion 14c extending outward in the radial direction over the entire circumference of the second end portion 14b. The flange portion 14c is in contact with the end surface (fixed surface 11a) where the pump mounting recess 12 is provided in the assembly direction of the electric oil pump 10 (the direction along the central axis L1 of the motor case 14). . The second end portion 14b of the motor case 14 is closed by a circuit case 16 that houses a circuit board 39 on which the circuit element 39a is mounted. The circuit case 16 and the flange portion 14c of the motor case 14 are fastened and fixed to the fixing surface 11a of the transmission 11 by screws (not shown).

  The pump mounting recess 12 of the transmission 11 has a circular shape when viewed in the assembly direction, and has a stepped shape with a larger inner diameter on the opening side (the fixed surface 11a side). A circular oil outlet passage 41 is formed in the bottom surface 12 a of the pump mounting recess 12, and a discharge port 37 of the pump case 15 is fitted into the oil outlet passage 41. As a result, the discharge port 37 b at the tip of the discharge port 37 is disposed in the oil outlet passage 41. Further, the inner peripheral surface of the oil outlet passage 41 and the outer peripheral surface of the discharge port 37 are sealed in a liquid-tight manner by a seal member 42.

  Also, oil from the oil pan is introduced into the pump mounting recess 12 at a position on the lower side in the vertical direction on the inner peripheral surface 12b of the pump mounting recess 12 (the inner peripheral surface on the bottom surface 12a side than the fitting recess 43). For this purpose, an oil introduction path 12c is formed.

  A circular fitting recess 43 is formed near the opening of the pump mounting recess 12, and a shaft fitting portion 44 formed in the motor case 14 is fitted into the fitting recess 43. The outer peripheral surface of the centering fitting portion 44 is formed in a circular shape centered on the central axis L1 of the motor case 14, and the centering fitting portion 44 is fitted into the fitting recess 43, so that the pump is mounted. The motor case 14 is aligned with respect to the recess 12.

  Further, a taper portion 46 whose diameter increases toward the fixed surface 11a is formed at the opening end portion (end portion on the fixed surface 11a side) of the pump mounting recess 12 over the entire circumference of the opening end portion. . A sealing portion 47 provided between the flange portion 14c of the motor case 14 and the shaft fitting portion 44 is pressed against the taper portion 46 in the direction of the axis L1. The part is sealed in a liquid-tight manner.

  In the motor case 14, the outer diameter of the portion on the first end portion 14 a side from the tip end portion 44 a (insertion tip) in the assembly direction of the shaft fitting portion 44 is smaller than the outer diameter of the shaft fitting portion 44. A gap is set between the small diameter portion 45 and the inner peripheral surface 12 b of the pump mounting recess 12.

  In addition, the oil inflow space S in the pump mounting recess 12 is between the radial direction of the outer diameter surface of the motor case 14 and the outer peripheral surface of the main body 31 (pump case 15) and the inner peripheral surface 12b of the pump mounting recess 12; It is formed over the axial direction between the bottom 31 a of the main body 31 and the bottom surface 12 a of the pump mounting recess 12. In the oil inflow space S, oil inflow from the oil introduction path 12c is allowed.

Next, the operation of this embodiment will be described.
In the electric oil pump 10 having the above-described configuration, the motor rotor 22, the rotary shaft 25, and the inner rotor portion 36b are rotated by the excitation of the coil 24 of the motor stator 21, and the outer rotor portion 36a is rotated by the engagement of the internal teeth Ta and the external teeth Tb. Then, the oil in the oil inflow space S is sucked into the pump chamber 33 from the suction port 31b and discharged from the discharge port 37b of the discharge port 37 to the oil outlet passage 41 by the pump action by the rotation of the inner rotor portion 36b and the outer rotor portion 36a. Is done. In the hydraulic pressure supply device D of the present embodiment, the oil introduction path 12c, the oil inflow space S, the suction port 31b, the pump chamber 33, the discharge port 37, and the oil outlet path 41 are sequentially arranged from the upstream side (oil pan side). It is an oil flow passage through which oil flows.

  Here, since the inner rotor portion 36b and the outer rotor portion 36a of the present embodiment are made of a resin material (engineering plastic), for example, the weight can be reduced and the buffering property (elasticity) is excellent as compared with a metal material. Therefore, the collision noise between the inner rotor portion 36 b and the outer rotor portion 36 a and between the outer rotor portion 36 a and the inner peripheral surface of the pump chamber 33 is suppressed. Furthermore, it is excellent in corrosion resistance and ease of molding compared to metal materials.

  On the other hand, the resin material is inferior in heat resistance, durability and mechanical properties (abrasion resistance and impact strength) as compared with the metal material. Therefore, in this embodiment, engineering plastics excellent in heat resistance, durability, and mechanical properties are adopted as the resin material constituting the inner rotor portion 36b and the outer rotor portion 36a in order to compensate for the disadvantages. Furthermore, in this embodiment, the strength of the inner rotor part 36b and the outer rotor part 36a is improved by mixing carbon fiber (or glass fiber) with the engineering plastic.

  In addition, since the inner rotor portion 36b and the outer rotor portion 36a are made of a resin material, the variation in the tip clearance (gap in the radial direction) between the external teeth Tb and the internal teeth Ta due to thermal expansion and contraction becomes significant. . That is, the tip clearance increases at a low temperature, and the tip clearance decreases at a high temperature. In the low temperature state, the viscosity of the oil increases and it becomes difficult to flow, but the chip clearance increases due to the low temperature, so that the surface pressure between the outer teeth Tb and the inner teeth Ta decreases, and as a result, power saving of the motor unit 17 (Ie, downsizing of the motor unit 17). On the other hand, when the tip clearance is large due to the low viscosity of the oil at high temperatures, the pump efficiency (volumetric efficiency) is significantly reduced. However, the tip clearance is reduced at high temperatures, so the reduction in pump efficiency is suppressed. ing.

  Further, when the variation in the tip clearance between the inner rotor portion 36b and the outer rotor portion 36a becomes significant, the inner rotor portion 36b, the outer rotor portion 36a, and the motor rotor 22 are likely to be shaken. Therefore, in the present embodiment, the motor rotor 22 is made of the embedded magnet type, so that even if the rotor core 26 interferes with the motor stator 21 due to shaft shake, the magnet 28 is prevented from directly contacting the motor stator 21. Has been.

  The continuous pole type motor rotor 22 employed in the present embodiment is a pseudo magnetic pole different from an actual magnet although the iron core portion 26b functions as a magnetic pole, and there is no magnet having a different magnetic pole in the vicinity of the magnet 28. The magnetic flux of the magnet 28 is likely to flow to parts other than the iron core part 26b. However, in this embodiment, since the pump rotor 36 (inner rotor portion 36b and outer rotor portion 36a) is made of resin, magnetization of the pump rotor 36 due to leakage magnetic flux is suppressed, and iron powder or the like is applied to the pump rotor 36 by magnetic force. Adsorption is prevented. Thereby, for example, it is prevented that good operation is hindered by iron powder or the like entering between the inner rotor portion 36b and the outer rotor portion 36a or between the outer rotor portion 36a and the inner peripheral surface of the pump chamber 33. ing.

  Further, when the motor unit 17 is driven, the oil in the oil pan flows into the oil inflow space S through the oil introduction path 12 c by the rotation (pump action) of the pump rotor 36, and the oil accumulated in the oil inflow space S In the state where the oil level (water level) reaches at least the inlet of the suction port 31b (in this embodiment, the lower end in the vertical direction), oil flows into the pump chamber 33 from the suction port 31b and oil from the discharge port 37b. It is discharged to the outlet path 41. In other words, the oil is supplied from the oil introduction path 12c to the oil outlet path 41 while maintaining the state where the oil is accumulated in the oil inflow space S.

  On the other hand, when the motor unit 17 is not driven, the oil in the oil pan does not flow into the oil inflow space S, but the check valve 38 in the discharge port 37 leads from the oil inflow space S to the oil introduction path 12c (oil pan side). The oil spill is suppressed. Specifically, when the motor unit 17 is not driven, the check valve 38 closes the flow path (constriction 37a) in the discharge port 37, so that air enters the pump chamber 33 from the oil outlet path 41. Accordingly, the outflow of oil from the oil inflow space S, that is, the lowering of the oil level in the oil inflow space S is suppressed. That is, even when the motor unit 17 is not driven, the state where oil is accumulated in the oil inflow space S is maintained.

  As described above, oil is stored in the oil inflow space S regardless of whether the motor unit 17 is driven or not. A part of the pump case 15 and the motor case 14 is immersed in the oil stored in the oil inflow space S. Thereby, the heat of the electric oil pump 10 (especially the heat generated in the motor stator 21) is preferably radiated to the transmission 11 side through oil that generally has better thermal conductivity than air.

  In addition, when the electric oil pump 10 is driven in a state where no oil is stored in the oil inflow space S, such as during an initial operation after the electric oil pump 10 is assembled in the pump mounting recess 12, the oil flows into the oil inflow space S from the oil introduction path 12c. The pump rotor 36 rotates with no oil in the pump chamber 33 until the oil level of the oil to reach reaches the suction port and the oil flows into the pump chamber 33. Here, in the present embodiment, the suction port 31b is provided on the lower side in the vertical direction than the pump rotor 36, and opens downward in the vertical direction, so that the oil level of the oil in the oil inflow space S is the suction port 31b. It is possible to shorten the time to reach the entrance. As a result, it is possible to shorten the time for which the pump rotor 36 rotates in the absence of oil. As a result, the generation of friction between the pump rotor 36 and the pump case 15 is suppressed, and the wear of the pump rotor 36 is reduced. Is to be suppressed.

  In the present embodiment, a check valve 38 is provided in the pump case 15 on the discharge port 37b side (downstream side of the flow path) with respect to the pump rotor 36 (pump chamber 33). This prevents air from entering the pump chamber 33 from the oil outlet passage 41 through the discharge port 37b, and as a result, corrosion of internal components (for example, the rotary shaft 25) due to water vapor in the air is suppressed. Yes.

Next, characteristic effects of the present embodiment will be described.
(1) An oil inflow between the inner surface of the pump mounting recess 12 and the outer surface of the housing 13 (the motor case 14 and the pump case 15) from which oil flows from the oil introduction path 12c based on the operation of the pump rotor 36. A space S is formed, and a part of the housing 13 is immersed in oil accumulated in the oil inflow space S. The pump case 15 is provided with a check valve 38 for suppressing the backflow of oil from the oil inflow space S to the oil introduction path 12c. According to this configuration, since a part of the housing 13 is immersed in the oil in the oil inflow space S, the heat of the housing 13 (especially the heat of the motor unit 17) is generally made of oil having a higher thermal conductivity than air. It is possible to suitably dissipate heat. In addition, since the backflow of oil from the oil inflow space S to the oil introduction path 12c is suppressed by the check valve 38 when the operation of the pump rotor 36 is stopped, heat dissipation due to a decrease in the oil in the oil inflow space S. Can be prevented from worsening.

  (2) Since the check valve 38 is provided on the discharge port 37b side with respect to the pump rotor 36, it is possible to prevent air from flowing into the pump chamber 33 from the oil outlet passage 41 through the discharge port 37b. it can. Thereby, it can suppress that internal components, such as the rotating shaft 25, corrode by the water vapor | steam in air.

  (3) The opening end (inlet end) of the suction port 31b is provided below the pump rotor 36 (pump chamber 33) in the vertical direction. For this reason, it is possible to shorten the time until the oil level (water level) of the oil in the oil inflow space S reaches the suction port 31b during operation in a state where no oil is accumulated in the oil inflow space S. As a result, it is possible to shorten the time for which the pump rotor 36 rotates in the absence of oil, and as a result, the wear of the pump rotor 36 can be suppressed and the reduction of the service life can be suppressed.

  (4) The housing 13 includes a discharge port 37 that protrudes in the axial direction and has a discharge port 37 b at the tip, and is fitted into the oil outlet passage 41. According to this configuration, alignment between the discharge port 37b of the electric oil pump 10 and the oil outlet passage 41 on the transmission 11 side is facilitated, and the assemblability can be improved.

  (5) Since the check valve 38 is provided in the discharge port 37, the space of the check valve 38 on the discharge port 37b side of the pump rotor 36 is secured, and the shaft of the housing 13 in the pump mounting recess 12 is secured. It can suppress that direction length (length which does not include the insertion insertion part to the oil extraction path 41) becomes long.

  (6) Since the inner rotor portion 36b and the outer rotor portion 36a constituting the pump rotor 36 are made of a resin material, corrosion of the inner rotor portion 36b and the outer rotor portion 36a can be suppressed, and further, the electric oil pump 10 can be reduced in weight. be able to. Since the inner rotor portion 36b and the outer rotor portion 36a are made of a resin material, the variation in the tip clearance between the external teeth Tb and the internal teeth Ta due to thermal expansion and contraction thereof becomes significant, and the inner rotor portion 36b and the outer rotor In this embodiment, since the motor rotor 22 is made of an embedded magnet type, even if the rotor core 26 interferes with the motor stator 21 due to the shaft shake, the magnet 28 is moved to the motor. Direct contact with the stator 21 is prevented, whereby damage and dropout of the magnet 28 can be suppressed.

  Note that when both the inner rotor portion 36b and the outer rotor portion 36a are made of resin as in the present embodiment, chip clearance variation (that is, shaft runout) becomes more prominent. The effect of suppressing the damage of the magnet 28 due to the above becomes even more remarkable.

  (7) In the motor rotor 22, a plurality of magnets 28 having one magnetic pole are embedded in the circumferential direction of the rotor core 26 made of a magnetic material to form a magnet magnetic pole portion 27, and the iron core of the rotor core 26 between the magnet magnetic pole portions 27. This is a continuous pole type rotor configured such that the portion 26b functions as the other magnetic pole. According to this configuration, the number of magnets 28 of the motor rotor 22 can be reduced. As a result, damage to the magnets 28 can be further suppressed, and the cost can be reduced.

  (8) The number of slots of the motor stator 21 (the number of teeth portions 23a) is set to an integral multiple of the number of magnet magnetic pole portions 27. As a result, when one magnet magnetic pole portion 27 faces one tooth portion 23a, the magnet magnetic pole portion 27 and the tooth portion 23a also face each other at other locations, so that the radial direction applied to the motor rotor 22 can be reduced. Uneven load can be reduced. Thereby, the vibration of the motor rotor 22 can be suppressed.

  (9) A shaft support hole 35 for supporting the rotary shaft 25 between the inner rotor portion 36b fixed to the rotary shaft 25 so as to be integrally rotatable and the motor rotor 22, and a motor rotor side (discharge port 37 side) than the inner rotor portion 36b. ), And a shaft support recess 34 that supports the rotary shaft 25 at the position. According to this configuration, the shaft support recess 34 and the shaft support hole 35 are provided on both sides in the axial direction of the inner rotor portion 36b to which a load is applied (so-called “both ends”), so that the shaft runout of the motor rotor 22 (rotating shaft 25) occurs. As a result, interference between the rotor core 26 and the motor stator 21 can be suppressed, and damage to the magnet 28 of the motor rotor 22 can be further suppressed.

  (10) Since the plastic material constituting the inner rotor portion 36b and the outer rotor portion 36a employs an engineering plastic excellent in heat resistance, durability, and mechanical properties (abrasion resistance and impact strength), the electric oil pump 10 Can contribute to the improvement of quality.

  (11) Since the inner rotor portion 36b and the outer rotor portion 36a are configured by including carbon fiber (or glass fiber) in a resin material (engineering plastic), the strength of the inner rotor portion 36b and the outer rotor portion 36a can be improved.

(12) Since the check valve 38 is provided in the housing 13 of the electric oil pump 10, the degree of freedom in design on the pump mounting recess 12 (transmission 11) side can be improved.
In addition, you may change the said embodiment as follows.

The configuration such as the shape of the pump case 15 is not limited to the above embodiment, and may be changed as appropriate.
For example, in the above embodiment, the inlet end portion of the suction port 31b is formed on the lower surface of the main body portion 31 of the pump case 15. However, for example, the suction port 31b has the same position as the pump chamber 33 in the vertical direction. Or you may comprise so that it may be located above the pump chamber 33. FIG. According to this configuration, since the oil level of the oil in the oil inflow space S can be raised, the area immersed in the oil in the motor case 14 and the pump case 15 can be increased. The heat of the motor case 14 and the pump case 15 can be radiated more suitably through the oil in the oil inflow space S.

  Further, in the above embodiment, the check valve 38 is provided in the discharge port 37 on the downstream side (discharge port 37b side) from the pump chamber 33, but other than this, for example, the upstream side (for example, the pump chamber 33) It may be provided in the suction port 31b.

  Moreover, in the said embodiment, although the discharge port 37 which has the discharge port 37b in the front-end | tip protruded from the pump case 15, for example, the discharge port 37 is abbreviate | omitted and the discharge port 37b (outlet) is made into the pump case 15 of this. You may form in a bottom face.

  In the above embodiment, the rotary shaft 25 is supported on both axial sides of the pump rotor 36. However, for example, the rotary shaft 25 may be supported on both axial sides of the motor rotor 22. .

  In the above embodiment, the number of slots (the number of teeth portions 23a) is set to an integral multiple of the number of magnet magnetic pole portions 27. However, the number of slots and the number of magnet magnetic pole portions 27 are not particularly limited thereto. May be appropriately changed according to the configuration.

  -Although the number of teeth of the inner rotor portion 36b (external teeth Tb) is four and the number of teeth of the outer rotor portion 36a (internal teeth Ta) is five, the number of teeth of the inner rotor portion 36b is calculated from the number of teeth of the outer rotor portion 36a. For example, the number of teeth of the inner rotor portion 36b may be six and the number of teeth of the outer rotor portion 36a may be seven.

  -In above-mentioned embodiment, although the inner rotor part 36b and the outer rotor part 36a were comprised with the engineering plastic containing carbon fiber (or glass fiber), it is not specifically limited to this, Carbon fiber and glass fiber are included. There may be no configuration. Further, as the engineering plastic constituting the inner rotor portion 36b and the outer rotor portion 36a, a polycarbonate-based material, a polyacetal-based material, or the like may be used in addition to the above-described polyimide-based material or polyamide-based material.

  In the above embodiment, both the inner rotor portion 36b and the outer rotor portion 36a are made of resin. However, the present invention is not particularly limited thereto, and either the inner rotor portion 36b or the outer rotor portion 36a may be made of resin.

  In the above embodiment, the inner rotor portion 36b and the motor rotor 22 are connected via the rotary shaft 25, so that the drive side (side connected to the rotary shaft 25) in the pump rotor 36 is the inner rotor portion 36b, and the driven side is Although the outer rotor portion 36a is used, the present invention is not particularly limited thereto. For example, an outer rotor portion may be provided on the inner periphery of the motor rotor 22 as a driving side, and a driven inner rotor portion may be provided inside the outer rotor portion.

  In the above-described embodiment, the outer rotor portion 36a and the inner rotor portion 36b of the pump rotor 36 may be constituted by an inclined gear in which the internal teeth Ta and the external teeth Tb are formed in a substantially spiral shape. According to this configuration, the internal teeth Ta and the external teeth Tb are engaged not only in the rotation direction but also in the axial direction, so that the shaft misalignment of the pump rotor 36 is suppressed and the generation of abnormal noise due to meshing is suppressed. Is possible.

  In the above embodiment, each tooth portion 23a (slot) of the stator core 23 may have a so-called skew structure in which the teeth 23a (slots) are inclined with respect to the axial direction. According to this structure, it can contribute to suppression of cogging torque.

  In the above embodiment, a part of the housing 13 (specifically, the entire pump case 15 and a part of the motor case 14) is configured to be accommodated in the pump mounting recess 12. However, the present invention is not particularly limited thereto. For example, it is good also as a structure by which the whole electric oil pump is accommodated in a pump attachment recessed part.

  In the hydraulic pressure supply device D of the above embodiment, the check valve 38 is provided in the discharge port 37 of the electric oil pump 10 in the oil flow passage through which oil flows, but is not particularly limited thereto, For example, as shown in FIGS. 4 and 5, the oil flow passage may be provided at a portion other than the discharge port 37. In the hydraulic pressure supply device D, the oil flow passage is composed of an oil introduction passage 12c, an oil inflow space S, a suction port 31b, a pump chamber 33, a discharge port 37, and an oil lead-out passage 41 in order from the upstream side (oil pan side). Has been.

  In FIG. 4, the check valve 38 is provided in the oil outlet passage 41 of the pump mounting recess 12 in the oil flow passage. The ball 38a of the check valve 38 is provided so as to be able to close the narrowed portion 41a formed in the oil outlet passage 41 from the downstream side, and the compression coil spring 38b biases the ball 38a from the downstream side toward the narrowed portion 41a. doing. The ball 38a closes the constricted portion 41a when the pump rotor 36 is not driven, moves away from the constricted portion 41a against the spring pressure by the oil pressure when the pump rotor 36 is driven, and the oil 38 Allow distribution.

  In FIG. 5, the check valve 38 is provided in the oil introduction path 12 c of the pump mounting recess 12 in the oil flow path. The ball 38a of the check valve 38 is provided so as to be able to close the narrowed portion 12d formed in the oil introduction passage 12c from the downstream side, and the compression coil spring 38b biases the ball 38a from the downstream side toward the narrowed portion 12d. doing. The ball 38a closes the constricted portion 12d when the pump rotor 36 is not driven, moves away from the constricted portion 12d against the spring pressure by the oil pressure when the pump rotor 36 is driven, and the oil in the oil introduction path 12c Allow distribution.

  As described above, even when the check valve 38 is provided in the oil lead-out path 41 or the oil introduction path 12c, the backflow of oil from the oil inflow space S to the oil introduction path 12c is reversed when the pump rotor 36 is stopped. Since it is suppressed by the stop valve 38, it is possible to suppress deterioration in heat dissipation due to a decrease in oil in the oil inflow space S. Further, since the check valve 38 is provided on the pump mounting recess 12 (transmission 11) side, the degree of freedom in designing the housing 13 of the electric oil pump 10 can be improved.

  DESCRIPTION OF SYMBOLS 10 ... Electric oil pump, 11 ... Transmission, 12 ... Pump installation recessed part, 12c ... Oil introduction path, 13 ... Housing, 14 ... Motor case, 15 ... Pump case, 17 ... Motor part, 31b ... Inlet, 36 ... Pump Rotor, 37 ... discharge port, 37b ... discharge port, 38 ... check valve, 41 ... oil outlet passage, S ... oil inflow space, D ... hydraulic pressure supply device.

Claims (3)

The motor unit and a pump rotor that rotates based on the driving of the motor unit are housed, and a housing having an oil inlet and an outlet is provided.
At least a part of the housing is inserted into the pump mounting recess, and the housing is configured to close the opening of the pump mounting recess with the housing,
Based on the operation of the pump rotor, the oil introduced from the oil introduction passage in the pump mounting recess is taken in from the suction port and led to the oil lead-out passage in the pump mounting recess through the discharge port. An oil pump,
Between the inner surface of the pump mounting recess and the outer surface of the housing, an oil inflow space into which oil flows in from the oil introduction path is formed based on the operation of the pump rotor, and is accumulated in the oil inflow space. A part of the housing is immersed in oil;
The housing is provided with a check valve for suppressing the backflow of oil from the oil inflow space to the oil introduction path , and the housing includes a discharge port having the discharge port .
The check valve is provided in the flow path portion up a flow path and the discharge port in the discharge port, check valve is the flow path of the non-driving time of the said discharge port in said pump rotor It closes and allows the oil in the discharge port to flow when the pump rotor is driven,
The opening end of the suction port on the oil inflow space side is provided vertically below the pump rotor,
The flow path portions in the suction port and the discharge port and closer to the pump rotor than the check valve respectively communicate with the pump chamber of the pump rotor,
The oil flow path from the oil introduction path to the oil lead-out path is, in order from the upstream side, the oil introduction path, the oil inflow space, the suction port, the pump chamber, the discharge port, and the oil lead-out path. And
The pump chamber, which is a flow path in the suction port and the discharge port and is closer to the pump rotor side than the check valve, is vertically below the rotation axis of the pump rotor. Electric oil pump, characterized in that it communicates with. The electric oil pump according to claim 1,
The housing comprises the discharge port with the discharge port in the distal end portion with axially projecting,
The electric oil pump, wherein the discharge port is fitted into the oil outlet path. A pump mounting recess having an oil introduction path and an oil outlet path, and an electric oil pump assembled in the pump mounting recess,
The electric oil pump includes a motor part and a pump rotor that rotates based on driving of the motor part, and includes a housing having an oil inlet and an outlet, and at least a part of the housing is provided in the pump mounting recess. The assembly is inserted and the opening of the pump mounting recess is closed by the housing,
Based on the operation of the pump rotor of the electric oil pump, the hydraulic pressure supply leads the oil introduced from the oil introduction passage into the pump mounting recess through the oil outlet passage through the suction port and the discharge port of the housing. A device,
Between the inner surface of the pump mounting recess and the outer surface of the housing, an oil inflow space into which oil flows in from the oil introduction path is formed based on the operation of the pump rotor, and is accumulated in the oil inflow space. A part of the housing is immersed in oil;
The housing is provided with a check valve for suppressing the backflow of oil from the oil inflow space to the oil introduction path , and the housing includes a discharge port having the discharge port .
The check valve is provided in the flow path portion up a flow path and the discharge port in the discharge port, check valve is the flow path of the non-driving time of the said discharge port in said pump rotor It closes and allows the oil in the discharge port to flow when the pump rotor is driven,
The opening end of the suction port on the oil inflow space side is provided vertically below the pump rotor,
The flow path portions in the suction port and the discharge port and closer to the pump rotor than the check valve respectively communicate with the pump chamber of the pump rotor,
The oil flow path from the oil introduction path to the oil lead-out path is, in order from the upstream side, the oil introduction path, the oil inflow space, the suction port, the pump chamber, the discharge port, and the oil lead-out path. And
The pump chamber, which is a flow path in the suction port and the discharge port and is closer to the pump rotor side than the check valve, is vertically below the rotation axis of the pump rotor. Hydraulic supply device characterized by being in communication with.