JP7040516B2 - Oil pump - Google Patents

Description

The present invention relates to an oil pump.

In recent years, electric oil pumps used for transmissions and the like are installed in existing spaces of vehicles, so that there are strict restrictions on mounting, and miniaturization is required so that they can be installed in various mounting spaces.

Further, the oil vibration of the oil discharged from the electric oil pump may cause the operation of the transmission in the half-clutch state to become unstable. In order to eliminate this risk, it is conceivable to increase the rotation speed of the oil pump. However, if the number of revolutions is simply increased, the flow rate of the oil increases and the pressure becomes excessive, and the pressure in the half-clutch state cannot be maintained.

On the other hand, Patent Document 1 discloses a continuously variable transmission control device capable of suppressing amplification of oil vibration generated in a control valve unit due to oil vibration of oil discharged from an electric oil pump. .. In this control valve unit, a plurality of valves for controlling the operation of the torque converter constituting the continuously variable transmission, the forward / backward switching mechanism, and the belt type continuously variable transmission mechanism are provided. These plurality of valves control the supply and discharge of oil discharged from the electric oil pump to control the operation of a plurality of devices of the continuously variable transmission. When there is a risk that the oil vibration is amplified in the control valve unit, the control device of the stepless transmission increases the line pressure connecting the electric oil pump and the control valve unit to reduce the oil vibration. Amplification is suppressed.

JP-A-2015-148310

The continuously variable transmission control device described in Patent Document 1 can suppress the amplification of the oil vibration of the oil discharged from the electric oil pump by increasing the line pressure. However, in the control device for the continuously variable transmission described in Patent Document 1, there is no means for directly detecting the line pressure, and the line pressure is detected from the command signal to the line pressure solenoid valve that controls the line pressure. Therefore, the detected line pressure may not be accurate.

An object of the present invention is to provide an oil pump capable of accurately detecting line pressure and miniaturization.

An exemplary first invention of the present application includes a shaft arranged along a central axis extending in the axial direction, a rotor rotating around the shaft, a stator arranged facing the rotor, the rotor, and the rotor. A pump portion having a motor portion having a housing for accommodating the stator, a pump rotor rotating with the shaft to suck and discharge oil, and a pump housing having an accommodating portion for accommodating the pump rotor. The pump housing has a suction port into which the oil is sucked, a discharge port from which the oil is discharged, and a pressure sensor arranged between the discharge port and the accommodating portion. However, the discharge port has a first discharge port and a second discharge port, and the pressure sensor is arranged between either one of the first discharge port and the second discharge port and the accommodating portion. When the discharge port is fully open, the second discharge port has a larger flow rate of the oil than the first discharge port, and the pressure sensor is arranged between the accommodating portion and the second discharge port. The pump portion has a solenoid valve capable of adjusting the flow rate of the oil discharged from the accommodating portion, and the solenoid valve has a flow path arranged between the discharge port and the accommodating portion. The solenoid valve has an opening / closing portion that can be opened / closed, and the solenoid valve is discharged to a second suction port from which the pressurized oil discharged from the pump portion is sucked and to an oil pan side where the pressurized oil can be stored. The pump body has three discharge ports, and the pump housing accommodates the pump rotor and has a bottom surface located on the side surface and the other side in the axial direction of the motor portion. The pump body having the accommodating portion and the shaft of the pump body. The pump cover has a pump cover that closes an opening that opens from one side in the direction to one side in the axial direction of the accommodating portion, and a receiving port that receives the oil discharged from the accommodating portion, and the pump cover has the receiving portion. It has a first flow path that communicates the port and the first discharge port, and a second flow path that communicates the receiving port and the second discharge port, and the second flow path is the solenoid valve. An oil pump in which the receiving port and the second discharge port are communicated with each other through the second suction port, and the second discharge port of the pump cover is connected to the third discharge port of the solenoid valve. ..

According to the first exemplary invention of the present application, it is possible to provide an oil pump that can accurately detect the line pressure and can be miniaturized.

It is a perspective view of the oil pump which concerns on 1st Embodiment. It is sectional drawing of the main part of an oil pump. It is a perspective view of the oil pump which illustrated the internal structure of a pump cover. It is a top view of the oil pump which illustrated the internal structure of a pump cover. It is an exploded perspective view of the pon cover to which a solenoid valve and a pressure sensor are attached. It is an exploded perspective view of an oil pump in which a pump cover is attached to a motor part provided with a pump body.

Hereinafter, the oil pump according to the embodiment of the present invention will be described with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present invention to the above-mentioned contents, but are merely explanatory examples. .. For example, expressions that represent relative or unique arrangements such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric" or "coaxial" are exact. Not only does it represent such an arrangement, but it also represents a tolerance or a state of relative displacement at an angle and distance to the extent that the same function can be obtained. For example, expressions such as "same", "equal", and "homogeneous" that indicate that things are in the same state not only represent exactly the same state, but also have tolerances or differences to the extent that the same function can be obtained. It shall also represent the existing state. For example, the expression representing a shape such as a quadrangular shape or a cylindrical shape not only represents a shape such as a quadrangular shape or a cylindrical shape in a geometrically strict sense, but also an uneven portion and a chamfer within the range where the same effect can be obtained. It shall also represent the shape including the part and the like. On the other hand, the expressions "equipped", "equipped", "equipped", "included", or "have" one component are not exclusive expressions excluding the existence of other components.

Further, in the drawings, the XYZ coordinate system is shown as a three-dimensional Cartesian coordinate system as appropriate. In the XYZ coordinate system, the Z-axis direction is a direction parallel to one axial direction of the central axis J shown in FIG. The X-axis direction is a direction parallel to the lateral direction of the oil pump shown in FIG. 1, that is, a vertical direction in FIG. The Y-axis direction is a direction orthogonal to both the X-axis direction and the Z-axis direction.

Further, in the following description, the positive side (+ Z side) in the Z-axis direction is referred to as "front side", and the negative side (-Z side) in the Z-axis direction is referred to as "rear side". The rear side and the front side are names used only for explanation, and do not limit the actual positional relationship and direction. Unless otherwise specified, the direction parallel to the central axis J (Z-axis direction) is simply referred to as "axial direction", and the radial direction centered on the central axis J is simply referred to as "diametrical direction". The circumferential direction around the center, that is, the circumference of the central axis J (θ direction) is simply referred to as the “circumferential direction”.

In the present specification, "extending in the axial direction" means not only extending in the strict axial direction (Z-axis direction) but also extending in a direction tilted within a range of less than 45 ° with respect to the axial direction. include. Further, in the present specification, "extending in the radial direction" means that it extends in a strictly radial direction, that is, in a direction perpendicular to the axial direction (Z-axis direction), and 45 ° with respect to the radial direction. Including the case where it extends in the direction of inclination within the range of less than.

FIG. 1 is a perspective view of an oil pump according to the first embodiment. FIG. 2 is a cross-sectional view of a main part of the oil pump.

[First Embodiment]
As shown in FIGS. 1 and 2, the oil pump 1 of the present embodiment has a motor unit 20 and a pump unit 3. The motor unit 20 has a shaft 41 arranged along a central axis J extending in the axial direction. The pump unit 3 is located on one side in the axial direction of the motor unit 20, is driven by the motor unit 20 via the shaft 41, and discharges oil. That is, the motor unit 20 and the pump unit 3 are provided side by side along the axial direction. Hereinafter, each component will be described in detail.

<Motor unit 20>
As shown in FIG. 2, the motor unit 20 includes a housing 21, a rotor 40, a shaft 41, a stator 50, and a bearing 55.

The motor unit 20 is, for example, an inner rotor type motor, in which the rotor 40 is fixed to the outer peripheral surface of the shaft 41, and the stator 50 is located on the radial outer side of the rotor 40. Further, the bearing 55 is arranged at the axial rear side (−Z side) end of the shaft 41 and rotatably supports the shaft 41.

(Housing 21)
The housing 21 has a bottomed thin-walled cylindrical shape, and has a bottom surface portion 21a, a stator holding portion 21b, a pump body holding portion 21c, a side wall portion 21d, and flange portions 24 and 25. The bottom surface portion 21a forms a bottomed portion, and the stator holding portion 21b, the pump body holding portion 21c, and the side wall portion 21d form a cylindrical side wall surface centered on the central axis J. In the present embodiment, the inner diameter of the stator holding portion 21b is larger than the inner diameter of the pump body holding portion 21c. The outer surface of the stator 50, that is, the outer surface of the core back portion 51, which will be described later, is fitted to the inner surface of the stator holding portion 21b. Therefore, the stator 50 is housed in the housing 21.

The flange portion 24 extends radially outward from the front side (+ Z side) end of the side wall portion 21d. On the other hand, the flange portion 25 extends radially outward from the rear side (−Z side) end portion of the stator holding portion 21b. The flange portion 24 and the flange portion 25 face each other and are fastened by a fastening means (not shown). Therefore, the motor unit 20 and the pump unit 3 are sealed and fixed in the housing 21.

As the material of the housing 21, for example, a zinc-aluminum-magnesium alloy or the like can be used, and specifically, a molten zinc-aluminum-magnesium alloy plated steel plate and a steel strip can be used. Since the housing 21 is made of metal, it has a large thermal conductivity and a large surface area, so that it has a high heat dissipation effect. Further, the bottom surface portion 21a is provided with a bearing holding portion 56 for holding the bearing 55.

(Rotor 40)
The rotor 40 has a rotor core 43 and a rotor magnet 44. The rotor core 43 surrounds the shaft 41 around the axis (in the θ direction) and is fixed to the shaft 41. The rotor magnet 44 is fixed to the outer surface of the rotor core 43 along the axis (θ direction). The rotor core 43 and the rotor magnet 44 rotate together with the shaft 41.

(Stator 50)
The stator 50 surrounds the rotor 40 around an axis (in the θ direction) and rotates the rotor 40 around the central axis J. The stator 50 has a core back portion 51, a teeth portion 52, a coil 53, and an insulator (bobbin) 54.

The shape of the core back portion 51 is a cylindrical shape concentric with the shaft 41. The teeth portion 52 extends from the inner surface of the core back portion 51 toward the shaft 41. A plurality of tooth portions 52 are provided, and are arranged at equal intervals in the circumferential direction of the inner surface of the core back portion 51. The coil 53 is provided around the insulator (bobbin) 54, and the conductive wire 53a is wound around the coil 53. The insulator (bobbin) 54 is attached to each tooth portion 52.

(Bearing 55)
The bearing 55 is arranged on the rear side (-Z side) of the rotor 40 and the stator 50, and is held by the bearing holding portion 56. The bearing 55 supports the shaft 41. The shape, structure, etc. of the bearing 55 are not particularly limited, and any known bearing can be used.

(Shaft 41)
The shaft 41 extends along the central axis J and penetrates the motor portion 20. The front side (+ Z side) of the shaft 41 protrudes from the motor portion 20 and extends into the pump portion 3. The front end (+ Z side) end of the shaft 41 is arranged in the discharge port 11 of the pump cover 8. The rear side (-Z side) of the shaft 41 protrudes from the motor portion 20 and is supported by a bearing 55 mounted in the bus bar holder 58.

<Pump section 3>
The pump unit 3 is located on one side in the axial direction of the motor unit 20, specifically, on the front side (+ Z side). The pump unit 3 is driven by the motor unit 20 via the shaft 41. The pump unit 3 has a pump rotor 4 and a pump housing 5. The pump housing 5 has a suction port 9, a discharge port 11, and a pressure sensor 70. Further, the pump housing 5 has a pump body 6, a pump cover 8, and a receiving port 12.

(Pump body 6)
The pump body 6 is fixed in the front side (+ Z side) of the housing 21 on the front side of the motor unit 20. The pump body 6 has an accommodating portion 7 accommodating the pump rotor 4 and having a side surface and a bottom surface located on the other side in the axial direction of the motor portion 20. The accommodating portion 7 opens to the front side (+ Z side) and is recessed to the rear side (−Z side). The shape of the accommodating portion 7 when viewed from the axial direction is a circular shape.

The pump body 6 has a through hole 6a penetrating along the central axis J. Both ends of the through hole 6a are opened in the axial direction to allow the shaft 41 to pass through, the front side (+ Z side) opening is opened in the accommodating portion 7, and the rear side (-Z side) opening is opened in the motor portion 20 side. .. The through hole 6a functions as a bearing that rotatably supports the shaft 41.

(Pump rotor 4)
The pump rotor 4 is attached to the shaft 41. More specifically, the pump rotor 4 is attached to the front side (+ Z side) of the shaft 41. The pump rotor 4 has an inner rotor 4a attached to the shaft 41 and an outer rotor 4b that surrounds the radial outer side of the inner rotor 4a. The inner rotor 4a has an annular shape. The inner rotor 4a is a gear having teeth on the outer surface in the radial direction.

The inner rotor 4a is fixed to the shaft 41. More specifically, the front end (+ Z side) end of the shaft 41 is press-fitted inside the inner rotor 4a. The inner rotor 4a rotates around the axis (in the θ direction) together with the shaft 41. The outer rotor 4b is an annular shape that surrounds the radial outer side of the inner rotor 4a. The outer rotor 4b is a gear having teeth on the inner side surface in the radial direction.

The inner rotor 4a and the outer rotor 4b mesh with each other, and the inner rotor 4a rotates to rotate the outer rotor 4b. That is, the pump rotor 4 rotates due to the rotation of the shaft 41. In other words, the motor unit 20 and the pump unit 3 have the same rotation axis. Therefore, it is possible to prevent the electric oil pump from becoming larger in the axial direction. Further, as the inner rotor 4a and the outer rotor 4b rotate, the volume between the meshing portion of the inner rotor 4a and the outer rotor 4b changes. The region where the volume decreases becomes the pressurized region, and the region where the volume increases becomes the negative pressure region. A suction port 10 is arranged on one side (front side) in the axial direction of the negative pressure region of the pump rotor 4. Further, a receiving port 12 is arranged on one side (front side) in the axial direction of the pressurizing region of the pump rotor 4. Here, the oil sucked into the accommodating portion 7 from the suction port 9 is accommodated in the volume portion between the inner rotor 4a and the outer rotor 4b, and is sent to the discharge port 11 side. After that, the oil is discharged from the discharge port 11.

(Pump cover 8)
The pump cover 8 is attached to one axial side (front side) of the pump body 6 and closes the opening 7a that opens on one axial side (front side) of the accommodating portion 7. In the embodiment shown in FIGS. 1 and 2, the pump cover 8 has a disc-shaped cover main body portion 8a extending in the radial direction and a protruding portion 8b protruding from the radial end portion of the cover main body portion 8a. The cover main body 8a closes the opening 7a on the front side of the accommodating portion 7.

(Cover body 8a)
The cover main body portion 8a has a first step portion 8a1 and a second step portion 8a2 protruding toward the front side (+ Z side) in the axial direction. The first step portion 8a1 has a cylindrical shape, is provided substantially coaxially with the central shaft J, and is connected to the central shaft side end portion of the surface 8a3 on the axial front side (+ Z side) of the cover main body portion 8a. The cover main body 8a has a through hole 8a4 along the central axis J. The through hole 8a4 penetrates between both ends of the pump cover 8 in the axial direction. The shaft 41 is passed through the through hole 8a4.

The second step portion 8a2 is provided substantially coaxially with the central axis J, and has a cylindrical shape having a smaller diameter than the first step portion 8a1. The second step portion 8a2 is connected to the central shaft side end portion of the surface 8a5 on the axial front side (+ Z side) of the first step portion 8a1. The second step portion 8a2 has a large diameter hole portion 8a6 having a diameter larger than that of the through hole 8a4 along the central axis J, and one end of the shaft 41 in the axial direction is arranged in the large diameter hole portion 8a6.

The discharge port 11 has a first discharge port 11a and a second discharge port 11b. In the present embodiment, the first discharge port 11a is a large-diameter hole portion 8a6. The second discharge port 11b is provided on the tip end side of the protruding portion 8b of the pump cover 8, although the details will be described later. A suction port 10 and a receiving port 12 are provided at the other end of the cover main body 8a. The suction port 10 is provided on the side opposite to the protrusion 8b with respect to the central axis J. The receiving port 12 is provided on the protruding portion 8b side with respect to the central axis J.

More specifically, as shown in FIGS. 2 and 3, the suction port 10 is provided at a position facing the negative pressure region, is curved in the circumferential direction with respect to the central axis J, and extends in an elongated hole shape. Further, the receiving port 12 is provided at a position facing the pressurized region, is curved in the circumferential direction with respect to the central axis J, and extends in an elongated hole shape. Therefore, the oil sucked from the suction port 9 can be supplied over substantially the entire area of the negative pressure region. Further, all of the oil supplied from the pressurized region can be received in the receiving port 12.

The suction port 9 communicates with the suction port 10 and opens at one end in the axial direction of the first stage portion 8a1. That is, the suction port 9 is provided so as to straddle the cover main body portion 8a and the first stage portion 8a1. Therefore, the suction port 9 is connected to the negative pressure region of the accommodating portion 7 via the suction port 10.

The first discharge port 11a and the reception port 12 are connected to each other via the communication passage 15. In the embodiment shown in FIG. 2, one end side of the communication passage 15 opens to the inner side surface of the first discharge port 11a, and the other end side opens to one axial side (front side) of the receiving port 12. Therefore, the oil received in the receiving port 12 can flow to the first discharge port 11a through the communication passage 15. The flow path 17 through which oil flows between the receiving port 12 and the first discharge port 11a is hereinafter referred to as a first flow path 13.

A control valve 81 is connected to the first discharge port 11a via the main flow path 80. The main flow path 80 supplies the oil discharged from the first discharge port 11a to the control valve 81. The control valve 81 controls the supply and discharge of oil supplied from the main flow path 80 to, for example, an automatic transmission of a vehicle.

(Protruding portion 8b)
As shown in FIGS. 1 and 2, the projecting portion 8b projects in a direction orthogonal to the axial direction from the other side end portion in the radial direction of the cover main body portion 8a. The tip of the protruding portion 8b is located radially outside the housing 21 of the motor portion 20. The protruding portion 8b has a substantially quadrangular shape when viewed from one side (front side) in the axial direction. A solenoid insertion hole 8b1 (see FIG. 5) penetrating in the axial direction is provided on the tip end side of the protrusion 8b. The opening opened on one side (front side) in the axial direction of the solenoid insertion hole 8b1 is the second discharge port 11b. The flow path 17 that communicates the second discharge port 11b and the accommodating portion 7 is hereinafter referred to as a second flow path 14.

(Second flow path 14)
As shown in FIGS. 2, 3, and 4, one end of the second flow path 14 is connected to the receiving port 12, and the other end is connected to the second discharge port 11b via the solenoid valve 60. In the illustrated embodiment, the second flow path 14 has a first through hole 14a extending from the receiving port 12 toward the tip end side of the protrusion 8b and penetrating at the tip end portion of the protrusion 8b, and one side of the protrusion 8b in the left-right direction. It extends from the end (minus side in the Y-axis direction) toward the solenoid insertion hole 8b1 side, penetrates the solenoid insertion hole 8b1, intersects the first through hole 14a, and extends toward the pressure sensor insertion hole 8b2 side to obtain pressure. It passes through a second through hole 14b that opens in the sensor insertion hole 8b2. A sealing member 16 for closing these openings is provided in the opening on the tip end side of the protrusion 8b of the first through hole 14a and the opening on one side in the left-right direction of the protrusion 8b of the second through hole 14b. Be done. In the illustrated embodiment, the sealing member 16 is a male screw.

That is, the second flow path 14 includes, among the first through holes 14a, the first through hole portion 14a1 between the intersection 14c where the first through hole 14a and the second through hole 14b intersect and the receiving port 12. Of the second through hole 14b, the second through hole portion 14b1 between the intersection 14c and the solenoid insertion hole 8b1 passes through. The second through-hole portion 14b1 is connected to the second suction port 62 of the solenoid valve 60, although the details will be described later. Further, the third discharge port 63 of the solenoid valve 60 is connected to the second discharge port 11b. Therefore, the second flow path 14 communicates the receiving port 12 and the second discharge port 11b via the second suction port 62 of the solenoid valve 60.

The second flow path 14 is provided in the pump cover 8 by, for example, cutting work (for example, drilling). For example, after cutting the first through hole 14a from the tip of the protruding portion 8b of the pump cover 8 toward the receiving port 12 side of the pump cover 8, from the end of the outer peripheral portion of the protruding portion 8b on the positive side in the Y-axis direction. The second through hole 14b is cut toward the solenoid insertion hole 8b1, the first through hole 14a, and the pressure sensor insertion hole 8b2. Then, female threads are provided at the opening end portion that opens to the outer peripheral portion of the protruding portion 8b of the first through hole 14a and the opening end portion that opens at the Y-axis direction plus side end portion of the protruding portion 8b of the second through hole 14b. , The sealing member 16 is screwed and fixed to each opening end. In this way, the second flow path 14 can be provided on the pump cover 8 by cutting. Therefore, the workability of the work of providing the second flow path 14 inside the pump cover 8 can be improved.

As described above, the pump cover 8 has a cover main body portion 8a and a protruding portion 8b as shown in FIG. Further, the pump cover 8 is arranged on one side (front side) in the axial direction of the motor unit 20, and the axial region of the pump cover 8 is arranged in a region different from the axial region of the motor unit 20. In the illustrated embodiment, the axial region of the pump cover 8 is arranged in the axial one side (front side) region of the motor unit 20. That is, the axial region of the pump cover 8 does not overlap in the axial direction with respect to the axial region of the motor unit 20, and the axial region of the pump cover 8 does not face the axial region of the motor unit 20. Placed in.

Therefore, the flow path length of the second flow path 14 can be shortened as compared with the case where the second flow path 14 is provided on the outer side in the radial direction of the motor unit 20. Therefore, since the pressure sensor 70 can be arranged near the pump rotor 4 which is the hydraulic pressure source, the pressure of the oil discharged from the pump rotor 4 can be detected more accurately.

(Solenoid valve 60)
FIG. 5 is an exploded perspective view of the pon cover 8 to which the solenoid valve 60 and the pressure sensor 70 are attached. As shown in FIGS. 2 and 5, the solenoid valve 60 includes a valve housing 64 that movably accommodates the opening / closing portion 65 inside, a driving portion 66 that moves the opening / closing portion 65 with respect to the valve housing 64, and one end portion. Has a solenoid feeding line 67 which is connected to the drive unit 66 and is provided with a solenoid valve side feeding terminal 67a at the other end. The opening / closing portion 65 extends in the longitudinal direction of the valve housing 64 and is movably supported to open / close the second suction port 62. In the illustrated embodiment, the opening / closing portion 65 is a spool.

The valve housing 64 has a second suction port 62 into which oil flowing through the second flow path 14 flows in, and a third discharge port 63 in which the inflowing oil is discharged. The second suction port 62 is opened and closed by moving the opening / closing portion 65. Therefore, by opening and closing the second suction port 62, the flow of oil flowing through the second flow path 14 can be blocked and allowed. Further, when the second suction port 62 is opened, the second suction port 62 and the third discharge port 63 are in a communicating state between the second suction port 62 and the third discharge port 63. Therefore, when the second suction port 62 is opened, the oil flowing through the second flow path 14 is discharged from the second discharge port 11b through the second suction port 62 and the third discharge port 63. Therefore, by opening and closing the second flow path 14 by the solenoid valve 60, a part of the oil flowing through the first flow path 13 can flow to the second flow path 14 side. Therefore, the flow rate of the oil to the supply destination of the pressurized oil supplied from the first discharge port 11a can be adjusted.

In the solenoid valve 60, when the second suction port 62 is opened by the opening / closing portion 65, the flow rate of the oil discharged from the second discharge port 11b is larger than the flow rate of the oil discharged from the first discharge port. It may be increased. In this case, for example, the opening area of the second discharge port 11b is made larger than the opening area of the first discharge port 11a. As described above, the second discharge port 11b allows more oil to flow than the first discharge port 11a, so that the range of the flow rate adjustment of the oil discharged from the first discharge port 11a can be expanded.

The drive unit 66 is, for example, an electromagnetic clutch. When power is supplied to the drive unit 66, the drive unit 66 moves the opening / closing unit 65 by the magnetic force generated from the drive unit 66 to open the second suction port 62, and the power supply to the drive unit 66 is cut off. Then, the opening / closing portion 65 is returned to the original position by the magnetic force of the spring (not shown), and the second suction port 62 is closed. Therefore, by controlling the power supply to the drive unit 66, the position of the opening / closing unit 65 can be adjusted to control the opening / closing of the second suction port 62.

The third discharge port 63 opens at one end in the longitudinal direction (one end in the axial direction) of the valve housing 64. On the other hand, the second discharge port 11b provided in the protruding portion 8b is an opening on one side (front side) in the axial direction of the solenoid insertion hole 8b1. The valve housing 64 of the solenoid valve 60 is inserted and fixed in the solenoid insertion hole 40b1. The valve housing 64 is supported in a state where one end in the axial direction is located substantially in the same plane as the second discharge port 11b. Therefore, the second discharge port 11b and the third discharge port 63 are arranged on substantially the same plane, and the second discharge port 11b and the third discharge port 63 are connected to each other to establish a communication state.

The second discharge port 11b is connected to an oil pan T capable of storing oil. In the illustrated embodiment, the second discharge port 11b communicates with the oil pan T via the tank flow path 83.

(Pressure sensor 70)
As shown in FIG. 1, the pressure sensor 70 is fixed to the protruding portion 8b and extends toward the motor portion 20. In the illustrated embodiment, the pressure sensor 70 is arranged outside the housing 21 of the motor unit 20 and fixed to the end of the protrusion 8b on the negative side in the Y-axis direction. As shown in FIG. 5, the pressure sensor 70 has a sensor unit 72 for detecting the oil pressure of oil, and an electric line holding unit 74 for holding a sensor electric line 75 electrically connected to the sensor unit 72. The sensor portion 72 has a columnar shape, and a male screw portion 72a is provided on the outer peripheral surface of the sensor portion 72. The pressure sensor insertion hole 8b2 is provided with a female threaded portion into which the male threaded portion 72a can be screwed. Therefore, the pressure sensor 70 is fixed to the pump cover 8 via the pressure sensor insertion hole 8b2.

As shown in FIG. 4, an opening 14b2 at the Y-axis direction plus side end of the second through hole 14b opens in the portion of the pressure sensor insertion hole 8b2 where the sensor portion 72 is inserted. The opening 14b2 communicates with the sensor portion 72. Therefore, the hydraulic pressure of the oil in the first flow path 13 and the second flow path 14 can be detected through the first through hole 14a and the second through hole 14b. That is, when the second flow path 14 is blocked by the solenoid valve 60, the pressure sensor 70 can detect the oil pressure in the first flow path 13, and the solenoid valve 60 opens the second flow path 14. In this case, the pressure sensor 70 can detect the oil pressure in the second flow path 14.

The pressure sensor 70 converts, for example, a change in electrical resistance due to the piezoresistive effect into an electrical signal. As shown in FIG. 5, the electric signal is sent to the sensor side terminal 75a provided on the sensor electric line 75 via the sensor electric line 75. The electric signal transmitted to the sensor-side terminal 75a is sent to, for example, an engine controller. The engine controller controls the operation of the vehicle's automatic transmission, engine, etc., and also controls the operation of the drive unit 66 (see FIG. 2) of the solenoid valve 60 based on the electric signal from the pressure sensor 70 to control the second suction. Controls the opening and closing of the mouth 62.

In this way, the sensor portion 72 of the pressure sensor 70 is fixed to the pressure sensor insertion hole 8b2 of the protruding portion 8b. Further, the protruding portion 8b extends in a direction orthogonal to the axial direction. Therefore, as shown in FIG. 2, the sensor unit 72 of the pressure sensor 70 is located between the first discharge port 11a or the second discharge port 11b and the accommodating unit 7 when viewed from a direction orthogonal to the axial direction. Is placed in. In the present embodiment, the sensor unit 72 is arranged between the first discharge port 11a and the accommodating unit 7, and between the second discharge port 11b and the accommodating unit 7. Therefore, the end portion of the pressure sensor 70 on one side in the axial direction (front side) does not protrude from the end portion on one side in the axial direction of the oil pump 1. Therefore, it is possible to suppress an increase in the axial length of the oil pump 1. The sensor unit 72 may be arranged between either one of the first discharge port 11a and the second discharge port 11b and the accommodating unit 7.

FIG. 6 is an exploded perspective view of the oil pump 1 in which the pump cover 8 is attached to the motor unit 20 provided with the pump body 6.

As shown in FIGS. 1 and 6, the electric line holding portion 74 and the solenoid valve 60 of the pressure sensor 70 are arranged adjacent to each other and extend along the axial direction of the motor portion 20. In the illustrated embodiment, the solenoid valve 60 is arranged at the center of the protruding portion 8b in the left-right direction (Y-axis direction) with respect to the protruding direction, and the electric line holding portion 74 is arranged on one side of the protruding portion 8b in the left-right direction. To. Further, the electric line holding portion 74 and the solenoid valve 60 are arranged in a direction orthogonal to the surface of the protruding portion 8b on the rear side (−Z side) in the axial direction. Therefore, since the pressure sensor 70 and the solenoid valve 60 are arranged along the axial direction of the motor unit 20, the oil pump is compared with the case where the pressure sensor 70 and the solenoid valve 60 are arranged so as to face different directions from each other. 1 can be miniaturized.

<Action / effect of oil pump 1>
Next, the operation / effect of the oil pump 1 will be described. As shown in FIG. 2, when the motor unit 20 of the oil pump 1 is driven, the oil sucked from the suction port 9 of the pump unit 3 moves in the accommodating unit 7 of the pump unit 3, and is connected to the receiving port 12. It is discharged from the first discharge port 11a via the passage 15. The oil discharged from the first discharge port 11a is supplied to the control valve 81 via the main flow path 80.

Here, since the pump unit 3 according to the present embodiment is a volume change type trochoid pump, oil vibration occurs in the oil discharged from the oil pump 1 due to the pressure fluctuation of the oil pump 1. Due to this oil vibration, for example, when the clutch of the automatic transmission is put into a half-clutch state, the operation may become unstable. In order to eliminate this instability, it is conceivable to increase the rotation speed of the oil pump 1 from, for example, 400 rotations to 1200 rotations to increase the frequency of oil vibration. However, simply increasing the number of revolutions to increase the frequency of oil vibration may cause resonance and prevent judder in a half-clutch state.

Therefore, in the oil pump 1 according to the present embodiment, the pump cover 8 of the pump housing 5 is a solenoid connected to a second flow path 14 communicating between the discharge port 11 (second discharge port 11b) and the accommodating portion 7. By having the valve 60, a part of the oil supplied from the first discharge port 11a to the pressurized oil supply destination (for example, the clutch destination) can flow to the solenoid valve 60 side. Therefore, for example, when the pressurized oil supply destination is the clutch destination, even if the rotation speed of the oil pump 1 is increased from 400 rotations to 1200 rotations, the increase in the flow rate of the oil supplied to the clutch is suppressed. be able to. Therefore, the frequency of oil vibration can be increased and shifted to a frequency for avoiding resonance. Therefore, it is possible to maintain the pressure in the half-clutch state while preventing judder in the half-clutch state.

Further, in the oil pump 1 according to the present embodiment, the pressure sensor 70 capable of detecting the oil pressure of the oil in the second flow path 14 is the discharge port 11 (first discharge port 11a and second discharge port 11b) and the accommodating portion 7. Placed between and. Therefore, the end portion of the pressure sensor 70 on one side in the axial direction (front side) does not protrude from the end portion on one side in the axial direction of the oil pump 1. Therefore, it is possible to suppress an increase in the axial length of the oil pump 1. Further, the oil pump 1 according to the present embodiment can be arranged in the vicinity of the pump rotor 4 which is a source of hydraulic pressure, as compared with the case where the pressure sensor 70 is provided in the control valve 81. Therefore, since the hydraulic pressure of the oil discharged from the pump rotor 4 can be accurately detected, the hydraulic pressures in the first flow path 13 and the second flow path 14 can be accurately detected.

Further, the solenoid valve 60 has a second suction port 62 into which the pressurized oil discharged from the pump unit 3 is sucked, and a third discharge port 63 discharged to the oil pan T side where the pressurized oil can be stored. Has. Further, the pump housing 5 has a pump body 6 having an accommodating portion 7 accommodating the pump rotor 4 and having a bottom surface located on the side surface and the other side in the axial direction of the motor portion, and one side (front side) in the axial direction of the pump body 6. It has a pump cover 8 that closes an opening 7a that opens on one side (front side) in the axial direction of the housing portion 7, and a receiving port 12 that receives oil discharged from the housing portion 7. The pump cover 8 has a first flow path 13 that communicates the receiving port 12 and the first discharge port 11a, and a second flow path 14 that communicates the receiving port 12 and the second discharge port 11b. The second flow path 14 communicates the receiving port 12 and the second discharge port 11b via the second suction port 62 of the solenoid valve 60. The second discharge port 11b of the pump cover 8 is connected to the third discharge port 63 of the solenoid valve 60.

Therefore, the second flow path 14 connecting the pump unit 3 and the solenoid valve 60 can be shortened. Therefore, it is possible to suppress the increase in size of the oil pump 1. Further, as compared with the case where the second flow path 14 is provided as a separate member, the number of parts can be reduced and the increase in cost of the oil pump 1 can be suppressed.

Further, the pump cover 8 has a protruding portion 8b protruding outward in the radial direction from the outer periphery of the motor portion 20, and the protruding portion 8b has a second flow path 14 and a second discharge port 11b. Therefore, the second flow path 14 and the second discharge port 11b can be provided in close proximity to each other. Therefore, it is possible to suppress the increase in size of the oil pump 1. Further, as compared with the case where the second flow path 14 is provided as a separate member, the number of parts can be reduced and the increase in cost of the oil pump 1 can be suppressed.

Further, the pressure sensor 70 and the solenoid valve 60 are fixed to the protruding portion 8b and extend toward the motor portion 20. Therefore, the pressure sensor 70 and the solenoid valve 60 can be arranged along the motor unit 20, and the size of the oil pump 1 can be suppressed.

Further, the pressure sensor 70 is arranged so that its longitudinal direction is parallel to the axial direction. Therefore, the miniaturization of the pump device can be promoted as compared with the case where the longitudinal direction of the pressure sensor 70 is arranged in the direction intersecting the axial direction.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and modifications can be made within the scope of the gist thereof.

1 Oil pump 3 Pump part 4 Pump rotor 5 Pump housing 6 Pump body 7 Accommodation part 7a Opening 8 Pump body 8a Protruding part 9 Suction port 11 Discharge port 11a 1st discharge port 11b 2nd discharge port 12 Inlet port 13 1st flow Road 14 2nd flow path 16 Sealing member 17 Flow path 20 Motor part 21 Housing 40 Rotor 41 Shaft 50 Stator 60 Solator valve 62 2nd suction port 63 3rd discharge port 65 Opening / closing part 70 Pressure sensor J Central axis

Claims (6)

Shafts arranged along a central axis extending in the axial direction,
A rotor that rotates around the shaft and
A stator arranged facing the rotor and
A housing for accommodating the rotor and the stator, and
And the motor part with
A pump rotor that rotates with the shaft to suck and discharge oil,
A pump housing having an accommodating portion for accommodating the pump rotor,
And the pump part with
Have,
The pump housing is
The suction port where the oil is sucked and
The discharge port from which the oil is discharged and
It has a pressure sensor disposed between the discharge port and the accommodating portion, and has.
The discharge port has a first discharge port and a second discharge port.
The pressure sensor is arranged between either one of the first discharge port and the second discharge port and the accommodating portion.
When the discharge port is fully open, the second discharge port has a larger flow rate of the oil than the first discharge port.
The pressure sensor is arranged between the accommodating portion and the second discharge port.
The pump unit has a solenoid valve that can adjust the flow rate of the oil discharged from the accommodating unit.
The solenoid valve has an opening / closing portion that can open / close a flow path arranged between the discharge port and the accommodating portion.
The solenoid valve is
A second suction port into which the pressurized oil discharged from the pump unit is sucked, and
A third discharge port for discharging the pressurized oil to the oil pan side where the pressurized oil can be stored,
Have,
The pump housing is
A pump body having the accommodating portion having a bottom surface for accommodating the pump rotor and located on the side surface and the other side in the axial direction of the motor portion.
A pump cover that closes an opening that opens from one side of the pump body in the axial direction to one side of the accommodating portion in the axial direction.
A receiving port for receiving the oil discharged from the accommodating portion,
Have,
The pump cover is
A first flow path that communicates the receiving port and the first discharging port,
A second flow path that communicates the receiving port and the second discharging port,
Have,
The second flow path communicates the receiving port and the second discharging port through the second suction port of the solenoid valve.
An oil pump in which the second discharge port of the pump cover is connected to the third discharge port of the solenoid valve. The pump cover is arranged on one side in the axial direction of the motor unit, and the pump cover is arranged on one side in the axial direction.
The oil pump according to claim 1 , wherein the axial region of the pump cover is different from the axial region of the motor unit. The oil according to claim 1 , wherein the pump cover has a protruding portion that protrudes radially outward from the outer periphery of the motor portion, and the protruding portion has the second flow path and the second discharge port. pump. The oil pump according to claim 3 , wherein the pressure sensor and the solenoid valve are fixed to the protruding portion and extend toward the motor portion. The oil pump according to claim 3 , wherein the pressure sensor is arranged in a longitudinal direction parallel to the axial direction. The second flow path extends in a direction orthogonal to the axial direction of the motor portion and penetrates from the inside to the outer peripheral portion of the pump cover.
The oil pump according to any one of claims 1 to 3, wherein a sealing member is arranged at an opening end portion of the second flow path that opens to the outer peripheral portion of the pump cover.

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