Vehicle oil pump drive device

Abstract

To provide a drive device of a vehicle oil pump which can simplify an oil pump and suppress the power consumption of a battery.SOLUTION: In the present invention, a second motor 21 comprises: a first rotor 23 which has a plurality of prescribed magnetic poles 23a; a stator 22 which generates a plurality of prescribed armature magnetic poles and generates a rotation magnetic field; and a second rotor 24 which has a plurality of prescribed soft magnetic materials 24a. The ratio of the number of armature magnetic poles, the number of magnetic poles and the number of soft magnetic materials is set to be 1:m:(1+m) / 2 (m≠1.0). The first rotor 23 is connected to an input shaft 6 to a transmission 4 from a first motor 11. The second rotor 24 is connected to an oil pump 5. First control for performing the drive of the oil pump 5 by the second rotor 24 by using the power of the input shaft 6, second control for performing the drive by using the power to the stator 22 from a battery 32, or third control for performing the drive by using both of the power of the input shaft 6 and the power from the battery 32 is selectively executed.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present invention relates to a drive device for a vehicle oil pump that drives an oil pump that supplies hydraulic pressure to a transmission mounted on a vehicle. [Background technology]

[0002] A conventional vehicle oil pump drive device is disclosed in, for example, Patent Document 1. This vehicle is a hybrid vehicle equipped with an engine and an electric motor as power sources, and is propelled by the power of at least one of the engine and the electric motor being changed in speed by a transmission and transmitted to drive wheels. In addition, a mechanical oil pump and an electric oil pump are provided to supply hydraulic oil pressure to the transmission. When the engine is started, the mechanical oil pump is driven by the power of the engine to supply hydraulic oil pressure to the transmission. On the other hand, when the engine is stopped, the electric oil pump is driven by the power of the pump motor supplied with power from an auxiliary battery to supply hydraulic oil pressure to the transmission. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-67001 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in this conventional hybrid vehicle, in addition to the mechanical oil pump driven by the engine, an electric oil pump driven by a pump motor powered by an auxiliary battery must be provided as an oil pump for the transmission, which increases the weight of the vehicle, the manufacturing costs of the pump, and the installation space. Also, when the electric oil pump is operated while the vehicle is running with the power of the electric motor with the engine stopped, power is always supplied from the auxiliary battery, which increases power consumption.

[0005] The present invention has been made to solve the above-mentioned problems, and aims to provide a drive device for a vehicle oil pump that can reduce the weight of the vehicle, the manufacturing costs and installation space of the oil pump by unifying the oil pump, and can suppress battery power consumption. [Means for solving the problem]

[0006] In order to achieve the above object, the invention according to claim 1 provides a drive device for a vehicle oil pump having an input shaft 6 to which power from a power source is input and driving an oil pump 5, the drive device comprising a first electric motor 11 having a rotatable rotor 13 connected to the input shaft 6, a second electric motor 21 connected to the oil pump 5, and a control means (ECU 2 in the embodiment (hereinafter the same in this section)) for controlling the second electric motor 21, the second electric motor 21 having a stator 22 connected to a battery (driving battery 32), and a stator 23 connected to the stator 24. The stator 22 has a first rotor 23 which faces the input shaft 6 in the radial direction, is rotatable in the circumferential direction, and is connected to the input shaft 6, and a second rotor 23 which is disposed between the stator 22 and the first rotor 23, is rotatable in the circumferential direction, and is connected to the oil pump 5. The first rotor 23 has a magnetic pole row which is composed of a predetermined number of magnetic poles (permanent magnets 23a) arranged in the circumferential direction and is arranged so that each two adjacent magnetic poles have different polarities. The stator 22 has a plurality of armatures (iron cores 22a, U-phase, V-phase and W-phase coils 22c arranged in the circumferential direction. , 22d, 22e) and disposed so as to face the magnetic pole row, the second rotor 24 has an armature row that generates a rotating magnetic field between the magnetic pole row and a predetermined number of armature magnetic poles generated in the plurality of armatures, the second rotor 24 has a soft magnetic material row disposed between the magnetic pole row and the armature row and is constituted by a predetermined number of soft magnetic bodies (cores 24a) arranged in the circumferential direction at intervals from each other, and a ratio of the number of armature magnetic poles to the number of magnetic poles to the number of soft magnetic bodies is set to 1:m:(1+m) / 2 (m≠1.0), and the control means is 8 ), in which the second rotor 24 is rotated and the oil pump 5 is driven by using power generated by the rotation of the first rotor 23 in synchronization with the input shaft 6; the second control (step 3 in FIG. 8 ), in which the second rotor 24 is rotated and the oil pump 5 is driven by supplying power from the battery to the stator 22; and the third control (step 5 in FIG. 8 ), in which the second rotor is rotated and the oil pump is driven by using both the power of the first rotor and the power supplied from the battery to the stator. The first electric motor 11 is connected to the internal combustion engine 3 via a clutch (first clutch CL1), and further includes a clutch state acquisition means (ECU2) for acquiring the clutch engagement / disengagement state, and an input shaft rotation speed detection means (input shaft rotation angle sensor 41) for detecting the rotation speed (input shaft rotation speed) Nin of the input shaft 6. The control means executes the second control when the clutch disengagement state is detected and the rotation speed Nin of the input shaft 6 is less than a predetermined first threshold value NREF1, and executes the third control when the rotation speed Nin of the input shaft 6 becomes equal to or greater than the first threshold value NREF1 during the execution of the second control. The present invention is characterized by the above.

[0007] Of the above-mentioned components of the present invention, the configuration of the second motor is the same as that of the motor disclosed in, for example, Patent No. 4747184 (hereinafter referred to as "Patent Application A") filed by the applicant of the present application, and its function has already been described in detail in Patent Application A, so a brief description will be given below. As described in Patent Application A, in the second motor configured as described above, when a rotating magnetic field is generated by supplying power to the armature of the stator, magnetic lines of force are generated that connect the magnetic poles of the first rotor, the soft magnetic material of the second rotor, and the armature magnetic poles of the stator, and the power supplied to the armature is converted into power by the action of the magnetic force of these magnetic lines of force, which is then transmitted to the first rotor and the second rotor and output.

[0008] In this case, the relationships between the electrical angular velocity and torque expressed by the following equations (1) and (2), respectively, are established among the rotating magnetic field of the stator, the first rotor, and the second rotor. ωmf = (α+1)·ωe2-α·ωe1 ···(1) Here, ωmf is the magnetic field electrical angular velocity (electrical angular velocity of the rotating magnetic field), ωe1 is the first rotor electrical angular velocity (value obtained by converting the angular velocity of the first rotor relative to the stator into electrical angular velocity), and ωe2 is the second rotor electrical angular velocity (value obtained by converting the angular velocity of the second rotor relative to the stator into electrical angular velocity). Also, α is the ratio (=a / c) between the number of pole pairs a of the magnetic poles of the first rotor and the number of pole pairs c of the armature magnetic poles of the stator (hereinafter referred to as "pole pair number ratio α").

[0009] Tmf = Te1 / α = -Te2 / (α+1) ···(2) Here, Tmf is the driving equivalent torque (torque equivalent to the power supplied to the armature and the magnetic field electrical angular velocity ωmf), Te1 is the first rotor transmission torque transmitted to the first rotor, and Te2 is the second rotor transmission torque transmitted to the second rotor.

[0010] In addition, in the second motor, when power is input to at least one of the first and second rotors and rotated relative to the armature while no power is being supplied to the armature, a rotating magnetic field is generated in the armature, generating power. In this case, magnetic field lines are generated that connect the magnetic poles, the soft magnetic material, and the armature magnetic poles, and the magnetic force of these magnetic field lines establishes the relationship of the electrical angular velocity in the above formula (1) and the torque relationship in the above formula (2). In other words, if the torque equivalent to the generated power and the magnetic field electrical angular velocity ωmf is defined as the power generation equivalent torque, the relationship shown in formula (2) also holds between this power generation equivalent torque and the first and second rotor transmission torques T1 and T2. Hereinafter, the driving equivalent torque and the power generation equivalent torque are collectively referred to as the "magnetic field equivalent torque Tmf."

[0011] The relationship between the electrical angular velocity and torque expressed by the above formulas (1) and (2) is exactly the same as the relationship between the rotational speed and torque of the sun gear, ring gear, and carrier of a planetary gear set in which the gear ratio between the sun gear and ring gear is 1:α. As is clear from the above, the second electric motor of the present invention has a function equivalent to that of a device that combines a single-pinion type planetary gear set with a general one-rotor type electric motor. Furthermore, compared with a planetary gear set, the second electric motor has a smaller number of parts and fewer shafts of the rotating bodies, and has the characteristic that power is transmitted between the rotating bodies (or between the rotating bodies and a rotating magnetic field) in a non-contact manner.

[0012] In addition, the drive device for a vehicle oil pump of the present invention includes a first electric motor separate from the second electric motor, and the rotor of the first electric motor is , the power of the power source is inputThe second electric motor is connected to the input shaft, and the first rotor of the second electric motor is connected to the input shaft and the second rotor is connected to the oil pump. Based on the above configuration, according to the present invention, the oil pump is selectively controlled by a first control (control in which the second rotor is rotated and the oil pump is driven using power generated by the first rotor rotating in synchronization with the input shaft), a second control (control in which the second rotor is rotated and the oil pump is driven by supplying power from the battery to the stator), and a third control (control in which the second rotor is rotated and the oil pump is driven using both the power of the first rotor and the power supplied from the battery to the stator).

[0013] In this way, the oil pump is driven by selectively executing the first control using the power of the input shaft, the second control using the power from the battery, and the third control using both the power and the power, which makes it possible to unify the oil pump unlike conventional devices, thereby reducing the weight of the vehicle, the manufacturing cost of the oil pump, and the installation space, thereby expanding the interior space of the vehicle, for example. Also, compared to the case where the oil pump is always driven by an electric motor connected to the battery, the battery power consumption can be suppressed.

[0014] Furthermore, the second motor can reduce the number of parts and the number of rotor shafts compared to a device that combines a planetary gear set and a one-rotor type motor having equivalent functions. Also, since there is no contact between the rotors (or between the rotating magnetic field and the rotors), it is possible to eliminate friction and rattle caused by the meshing of gears in a planetary gear set, power transmission loss between the rotors caused by these, and lubrication of the gears. Furthermore, unlike the rotor of a normal motor, the rotating magnetic field of the stator does not have inertial mass, so there is no response delay due to inertia to rotational fluctuations in the power of an internal combustion engine, for example, and the responsiveness of the drive of the oil pump can be improved.

[0016] Also,The first electric motor is connected to the internal combustion engine via a clutch, and the second control is executed when the disengaged state of the clutch is detected and the detected rotation speed of the input shaft is less than a predetermined first threshold value. In this way, when the transmission of power from the internal combustion engine to the transmission is interrupted and the actual rotation speed of the input shaft is low and the power is insufficient, the second control is executed to drive the oil pump using electric power from the battery. For example, before driving the vehicle with the first electric motor, the oil pump is driven by the second control to start up the transmission in advance, thereby enabling the vehicle to be driven smoothly thereafter by the first electric motor.

[0017] Furthermore, when the oil pump is driven using a planetary gear device at low vehicle speeds where the input shaft rotation speed is low, gear backlash can cause rattling noise, particularly when switching between the first and second controls, which can be easily heard by the driver and can reduce marketability. In contrast, the present invention uses a non-contact second electric motor without gears, which can prevent rattling noise and improve marketability.

[0019] moreover, When the rotation speed of the input shaft becomes equal to or greater than the first threshold value while the second control is being executed, the third control is executed. In this manner, when the rotation speed of the input shaft increases and the power of the input shaft increases sufficiently, the second control is switched to the third control, so that the power of the input shaft can be effectively used to drive the oil pump and the power consumption of the battery can be reduced.

[0020] Claim 2 The invention according to claim 1 In the drive device of the vehicle oil pump described above, the control means is characterized in that when the rotation speed Nin of the input shaft 6 becomes equal to or greater than a predetermined second threshold value NREF2 that is greater than the first threshold value NREF1, the control means holds the magnetic field rotation speed of the second motor 21 at a negative value and executes the first control.

[0021] According to this configuration, when the rotation speed of the input shaft becomes equal to or greater than a second threshold value that is greater than the first threshold value, the first control of the second motor is executed. In this way, when the rotation speed of the input shaft increases significantly, the first control of the second motor is executed to reduce the rotation speed of the second rotor and reduce the load on the oil pump. In addition, by charging the electric power generated by the first control into a battery, the electric power can be used as electric power for the second control or as electric power to drive other auxiliary devices. [Brief description of the drawings]

[0022] [Figure 1] 1 is a diagram illustrating a schematic diagram of a vehicle oil pump drive device according to an embodiment of the present invention, together with other configurations of the vehicle. [Diagram 2] 2 is a block diagram showing an ECU and the like of a drive device for a vehicle oil pump. [Diagram 3] 3 is a block diagram showing an electrical connection relationship between a first and a second electric motor of a drive device for a vehicle oil pump. [Figure 4] FIG. 4 is an enlarged cross-sectional view of a second electric motor. [Diagram 5] 4 is a schematic diagram showing a stator, first and second rotors of a second electric motor, developed in the circumferential direction. FIG. [Figure 6] FIG. 4 is a speed collinear diagram showing an example of the relationship between the magnetic field electrical angular velocity and the first and second rotor electrical angular velocities in the second electric motor. [Figure 7] 11 is a diagram for explaining an operation when power is supplied to the stator in a state in which the first rotor of the second electric motor is held non-rotatable. FIG. [Figure 8] 4 is a flowchart showing a drive control process of an oil pump. [Figure 9] FIG. 11 is a diagram showing the relationship between the input shaft rotation speed, the pump rotation speed, and the magnetic field rotation speed and the control mode of the second motor. [Figure 10] 13 is a flowchart showing a magnetic field equivalent torque calculation process. [Figure 11]FIG. 9 is a speed collinear diagram showing an example of the relationship between the rotation speeds of various rotating elements, obtained by the second control in FIG. 8, together with the torque relationships. [Figure 12] FIG. 9 is a speed collinear diagram showing an example of the relationship between the rotation speeds of various rotating elements, obtained by the third control in FIG. 8, together with the torque relationships. [Figure 13] FIG. 9 is a speed collinear diagram showing an example of the relationship between the rotation speeds of various rotating elements, obtained by the first control in FIG. 8, together with the torque relationships. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Fig. 1 shows an oil pump drive device according to an embodiment of the present invention together with other configurations of a related vehicle. The vehicle V includes an internal combustion engine 3 and a first electric motor 11 as a power source, a second electric motor 21, a hydraulic transmission 4, an oil pump 5 that supplies hydraulic pressure to the transmission 4, and an ECU (electronic control unit) 2 for controlling the internal combustion engine 3 and the first and second electric motors 11, 21. For convenience, hatching will be omitted for parts showing cross sections in the drawings.

[0024] The internal combustion engine (hereinafter referred to as "engine") 3 is, for example, a gasoline engine, and includes a crankshaft 3a for outputting power, a fuel injection valve 3b, and an ignition plug 3c. The operations of the fuel injection valve 3b and the ignition plug 3c are controlled by an ECU 2 (see FIG. 2). The crankshaft 3a is coaxially connected to an input shaft 6 via a first clutch CL1.

[0025] The first electric motor 11 is, for example, a brushless DC motor, and has a stationary stator 12 and a rotatable rotor 13. The stator 12 is made up of a three-phase coil and is fixed to a case CA. The rotor 13 is made up of a plurality of magnets and is provided radially inside the stator 12 and is integrally connected to the input shaft 6 coaxially.

[0026] As shown in FIG. 3, the stator 12 is electrically connected to a chargeable and dischargeable driving battery 32 via a first PDU (power drive unit) 31. The first PDU 31 is composed of an electric circuit such as an inverter, and the operation of the first electric motor 11 is controlled by controlling the first PDU 31 with the ECU 2. Specifically, when power is supplied from the driving battery 32 to the stator 12 under the control of the first PDU 31 by the ECU 2, the power is converted into motive power to rotate the rotor 13 (power running). Also, when the rotor 13 rotates with the supply of power to the stator 12 stopped, the motive power is converted into electric power to generate power (regeneration). The generated electric power is charged to the driving battery 32, etc.

[0027] The second electric motor 21 is of a two-rotor type configured as described below, and includes a stationary stator 22, a rotatable first rotor 23 provided radially inside the stator 22, and a rotatable second rotor 24 provided between the stator 22 and the first rotor 23. The stator 22, the first rotor 23, and the second rotor 24 are arranged concentrically with the input shaft 6, and the first rotor 23 is integrally connected to the input shaft 6. An output gear G1 is integrally provided on the second rotor 24, and the output gear G1 meshes with an input gear G2 that is integral with the input shaft 5a of the oil pump 5. The configuration and operation of the second electric motor 21 will be described later.

[0028] The oil pump 5 is driven by the power of the second rotor 24, and supplies the hydraulic pressure generated thereby to the transmission 4 via a hydraulic pressure supply path 7. The transmission 4 is, for example, configured as a belt-type continuously variable transmission having a drive pulley and a driven pulley driven by the hydraulic pressure, and a belt (neither shown) wound between the two pulleys. The transmission 4 changes the speed of the power of the engine 3 and / or the first electric motor 11 input from the input shaft 6 via the second clutch CL2. The changed speed power is transmitted to the left and right drive wheels DW, DW via a differential 8 and left and right output shafts 9, 9.

[0029] Next, we will explain the configuration and operation of the second electric motor 21. Note that the second electric motor 21 is basically the same as the electric motor disclosed in Patent Application A by the present applicant, so the configuration and operation will be briefly explained below.

[0030] The stator 22 of the second electric motor 21 generates a rotating magnetic field, and includes an iron core 22a and U-phase, V-phase, and W-phase coils 22c, 22d, and 22e provided on the iron core 22a, as shown in Figs. 4 and 5. The iron core 22a is cylindrical and made of a plurality of laminated steel plates, extends in the axial direction of the input shaft 6 (hereinafter simply referred to as the "axial direction"), and is attached to the inner circumferential surface of the case CA. In addition, twelve slots 22b, for example, are formed on the inner circumferential surface of the iron core 22a, and these slots 22b extend in the axial direction and are arranged at equal intervals in the circumferential direction of the input shaft 6 (hereinafter simply referred to as the "circumferential direction"). The U-phase to W-phase coils 22c to 22e are wound in the slots 22b by distributed winding (wave winding).

[0031] 3, the stator 22 including the U-phase to W-phase coils 22c to 22e is connected in parallel to the DC / DC converter 34, the drive battery 32, and the auxiliary battery 35 via the second PDU 33. The second PDU 33 is composed of electric circuits such as an inverter, similar to the first PDU 31, and outputs the DC power supplied from the drive battery 32 to the stator 22 in a state in which the DC power is converted into three-phase AC power under the control of the ECU 2. The DC / DC converter 34 outputs the power from the drive battery 32 in a boosted state to the second PDU 33, and also outputs the power from the second PDU 33 in a reduced state to the drive battery 32.

[0032] In the stator 22 configured as described above, when power is supplied from the drive battery 32 via the second PDU 33, or when power is generated as described below, four magnetic poles are generated at equal intervals in the circumferential direction at the end of the iron core 22a on the first rotor 23 side (see FIG. 7), and a rotating magnetic field caused by these magnetic poles rotates in the circumferential direction. Hereinafter, the magnetic poles generated in the iron core 22a are referred to as "armature magnetic poles." Also, as shown in FIG. 7, the polarities of each two armature magnetic poles adjacent in the circumferential direction are different from each other. In FIG. 7, the armature magnetic poles are indicated by (N) and (S) on the iron core 22a and the U-phase to W-phase coils 22c to 22e.

[0033] 5, the first rotor 23 has a magnetic pole row consisting of, for example, eight permanent magnets 23a. These permanent magnets 23a are arranged at equal intervals in the circumferential direction, and this magnetic pole row faces the iron core 22a of the stator 22. Each permanent magnet 23a extends in the axial direction, and its axial length is set to be the same as that of the iron core 22a of the stator 22.

[0034] As shown in FIG. 4, the permanent magnet 23a is attached to the outer circumferential surface of the ring-shaped mounting portion 23b. The mounting portion 23b is made of a soft magnetic material, for example, iron or a laminate of multiple steel plates, and is integrally connected to the input shaft 6 at its inner circumferential portion via a disk-shaped connecting portion 23c. As described above, the first rotor 23 including the permanent magnet 23a rotates integrally with the input shaft 6. Furthermore, since the permanent magnet 23a is attached to the outer circumferential surface of the mounting portion 23b made of a soft magnetic material as described above, each permanent magnet 23a has one magnetic pole, either (N) or (S), at the end on the stator 22 side. In FIG. 7, the magnetic poles of the permanent magnet 23a are represented by (N) and (S). Furthermore, the polarities of each two permanent magnets 23a adjacent to each other in the circumferential direction are different from each other.

[0035] The second rotor 24 has a single soft magnetic material row consisting of, for example, six cores 24a. These cores 24a are fixed to a disk-shaped flange (not shown) in a state where they are arranged at equal intervals in the circumferential direction, and are rotatably supported via the flange or the like. The soft magnetic material rows are arranged at predetermined intervals between the iron core 22a of the stator 22 and the magnetic pole row of the first rotor 23. Each core 24a is made of a soft magnetic material, for example, a laminate of multiple steel plates, and extends in the axial direction. The axial length of the core 24a is set to be the same as that of the iron core 22a of the stator 22, similar to the permanent magnet 23a. Furthermore, an input gear G1 for driving the oil pump 5 is integrally provided on the core 24a.

[0036] Next, the operation of the second motor 21 configured as above will be described. As described above, the second motor 21 has four armature poles, eight magnetic poles of the permanent magnets 23a (hereinafter referred to as "magnetic poles"), and six cores 24a. That is, the ratio of the number of armature poles to the number of magnetic poles to the number of cores 24a (hereinafter referred to as "pole ratio") is 1:m:(1+m) / 2=1:2.0:(1+2.0) / 2, where m=2.0. In addition, the number of magnetic pole pairs a=4, the number of soft magnetic bodies b=6, and the number of armature pole pairs c=2, where the pole pair ratio α=a / c=2.0.

[0037] In the second electric motor 21 configured as described above, when a rotating magnetic field is generated by supplying power to the stator 22 with the first rotor 23 fixed, as shown in Fig. 7 for example, magnetic field lines ML are generated that connect the magnet poles, the core 24a, and the armature poles, and the power supplied to the stator 22 is converted into power by the action of the magnetic force of these magnetic field lines ML, and the power is output from the second rotor 24. In this case, the relationship of the above formula (1) is established between the magnetic field electrical angular velocity ωmf and the first and second rotor electrical angular velocity ωe1, ωe2, and in this example, since the pole pair number ratio α of formula (1) is 2.0, the following formula (3) is established. ωmf = 3·ωe2-2·ωe1 ···(3)

[0038] For this reason, when the relationship among the magnetic field electrical angular velocity ωmf, the first rotor electrical angular velocity ωe1, and the second rotor electrical angular velocity ωe2 is expressed by a speed collinear diagram, it becomes as shown in FIG. 6, for example.

[0039] Furthermore, the relationship of the above-mentioned formula (2) is established between the magnetic field equivalent torque Tmf and the first and second rotor transmission torques Te1, Te2. By substituting the pole pair ratio α=2.0 into formula (2), the following formula (4) is obtained. Tmf = Te1 / 2 = -Te2 / 3 (4)

[0040] Furthermore, when power is input to at least one of the first and second rotors 23, 24 to rotate relative to the stator 22 while no power is being supplied to the stator 22, power is generated and a rotating magnetic field is generated in the stator 22. In this case as well, magnetic field lines ML are generated that connect the magnet poles, the soft magnetic material, and the armature poles, and the magnetic force of these magnetic field lines ML establishes the relationship between the electrical angular velocity shown in equation (3) and the torque relationship shown in equation (4).

[0041] As is clear from the above, the second electric motor 21 has the same function as a device that combines a single-pinion type planetary gear device with a general one-rotor type electric motor.

[0042] In addition, the input shaft 6 and the input shaft 5a of the oil pump 5 are provided with an input shaft rotation angle sensor 41 and a pump rotation angle sensor 42, respectively. The input shaft rotation angle sensor 41 detects the rotation angle of the input shaft 6 as an input shaft rotation angle θR1, and the pump rotation angle sensor 42 detects the rotation angle of the input shaft 5a of the oil pump 5 as a pump rotation angle θR2. These detection signals are output to the ECU 2.

[0043] The ECU 2 is configured with a microcomputer including an I / O interface, a CPU, a RAM, a ROM, etc. The ECU 2 calculates (detects) the rotation speed (hereinafter referred to as "input shaft rotation speed") Nin of the input shaft 6 and the first rotor 23, which are integral with each other, based on the detected input shaft rotation angle θR1, and calculates (detects) the rotation speed (hereinafter referred to as "pump rotation speed") Nop of the input shaft 5a of the oil pump 5 based on the detected pump rotation angle θR2. The ECU 2 controls the operation of the second electric motor 21 by controlling the rotating magnetic field of the stator 22 according to the detected input shaft rotation speed Nin and pump rotation speed Nop, etc., thereby controlling the operation of the second electric motor 21 and driving the oil pump 5.

[0044] Next, the drive control process of the oil pump 5 executed by the ECU 2 will be described with reference to Fig. 8. This process is repeatedly executed at a predetermined cycle. In this process, first, in step 1 (shown as "S1"; the same applies below), it is determined whether or not the first clutch flag F_CL1 is "1". This first clutch flag F_CL1 is set to "1" when the first clutch CL1 arranged between the engine 3 and the first electric motor 11 is in an engaged state.

[0045] When the determination result in step 1 is NO, that is, when the first clutch CL1 is in a disengaged state, the process proceeds to step 2, where it is determined whether or not the detected input shaft rotation speed Nin is less than a predetermined first threshold value NREF1 close to the value 0. When the determination result is YES, that is, when the input shaft rotation speed Nin is a low value close to 0, the process proceeds to step 3, where the second control of the second electric motor 21 is executed (see FIG. 9), and the process ends.

[0046] 10 shows a calculation process of the magnetic field equivalent torque. In this process, first, a basic value Te2b of the second rotor transmission torque Te2 is calculated in step 11. The calculation is performed based on a target pump rotation speed Nopt, which is a target value of the pump rotation speed, for example.

[0047] Next, in step 12, a correction term ΔTe2 for the second rotor transmission torque Te2 is calculated based on the target pump rotation speed Nopt and the detected actual pump rotation speed Nop. The calculation of this correction term ΔTe2 is performed by feedback control so that the pump rotation speed Nop becomes the target pump rotation speed Nopt (so that the deviation ΔNop between them converges to a value of 0).

[0048] Next, in step 13, the second rotor transmission torque Te2 is calculated by adding the correction term ΔTe2 to the basic value Nopt using the following equation (5). Te2 = Te2b + ΔTe2 (5)

[0049] Next, in step 14, the magnetic field equivalent torque Tmf is calculated by using the second rotor transmission torque Te2 and the above-mentioned equation (4). Then, in step 15, a drive signal based on the calculated magnetic field equivalent torque Tmf is output to the stator 22 of the second electric motor 21, and this process ends.

[0050] FIG. 11 shows an example of the relationship between the rotational speeds of various rotating elements obtained by the second control, together with the torque relationship. First, since the first rotor 23 is directly connected to the input shaft 6, the rotational speeds of both 23 and 6 are equal to the input shaft rotational speed Nin. Also, since the second rotor 24 is connected to the input shaft 5a of the oil pump 5 via the output gear G1 and the input gear G2, the rotational speeds of the second rotor 24 and the input shaft 5a of the oil pump 5 are equal to the pump rotational speed Nop, ignoring the shifting caused by the gears G1 and G2. Due to these relationships and the function of the second electric motor 21 similar to the planetary gear device described above, during the second control, the input shaft rotational speed Nin, the pump rotational speed Nop, and the magnetic field rotational speed (rotational speed of the rotating magnetic field) Nef are expressed in a collinear relationship as shown in FIG. 11, and the input shaft rotational speed Nin indicates a value of 0 or close to 0.

[0051] Therefore, during the second control, the second rotor transmission torque Te2 corresponds to the load of the oil pump 5. Since the input shaft 6 for transmitting the vehicle driving force is connected to the first rotor 23, the reaction force Te1 of Te2 acts. And in such a state, based on the magnetic field equivalent torque Tmf, power is supplied to the stator 22 to rotate the rotating magnetic field forward and act as the driving equivalent torque. As a result, the pump rotational speed Nop increases. Also, as described above, since the magnetic field equivalent torque Tmf is calculated by feedback control so that the pump rotational speed Nop becomes the target pump rotational speed Nopt, the pump rotational speed Nop is maintained at the target pump rotational speed Nopt, thereby enabling the oil pump 5 to be driven well. As described above, during the second control, the oil pump 5 is driven using only the power of the second electric motor 21.

[0052] Returning to FIG. 8, when the determination result in step 1 is YES and the first clutch CL1 is in the engaged state, or when the determination result in step 2 is NO and the input shaft rotational speed Nin is equal to or greater than the first threshold value NREF1, the process proceeds to step 4 to determine whether the input shaft rotational speed Nin is equal to or greater than a predetermined second threshold value NREF2 that is greater than the first threshold value NREF1. If this determination result is NO, NREF1 ≤ Nin < NREF2 is satisfied, and the input shaft rotational speed Nin has increased to near the target pump rotational speed Nopt, the process proceeds to step 5 to execute the third control of the second electric motor 21 (see FIG. 9), and this process ends.

[0053] This third control is executed for the purpose of converging the pump rotational speed Nop to the target pump rotational speed Nopt. Therefore, its content is basically the same as the second control in FIG. 10 described above. That is, the basic value Te2b of the second rotor transmission torque Te2 is calculated, and a correction term ΔTe2 is calculated by feedback control so that the pump rotational speed Nop becomes the target pump rotational speed Nopt. The sum of both Te2 and ΔTe2 is set as the second rotor transmission torque Te2, and based on this second rotor transmission torque Te2, the magnetic field equivalent torque Tmf is calculated by the above formula (4).

[0054] During the third control, since the input shaft rotation speed Nin has increased to a certain extent, the first rotor transmission torque Te1 acts as a drive torque in a direction to increase the pump rotation speed Nop. In contrast, the magnetic field equivalent torque Tmf is calculated so that the pump rotation speed Nop becomes the target pump rotation speed Nopt, and adjusts the pump rotation speed Nop by acting as a drive equivalent torque or a power generation equivalent torque. As a result, as shown in FIG. 12, the pump rotation speed Nop is maintained at the target pump rotation speed Nopt regardless of the input shaft rotation speed Nin, and the oil pump 5 can be driven satisfactorily. As described above, during the third control, the oil pump 5 is driven mainly by using the power of the engine 3 and / or the first electric motor 11.

[0055] Returning to FIG. 8, when the judgment result in step 4 is YES and the input shaft rotation speed Nin is equal to or greater than the second threshold value NREF2, it is determined that the input rotation speed Nin has increased significantly, and the process proceeds to step 6, where the first control of the second electric motor 21 is executed (see FIG. 9), and this process is terminated.

[0056] In the first control, the magnetic field equivalent torque Tmf is made to act as a power generation equivalent torque, thereby reversing the rotating magnetic field, keeping the magnetic field rotation speed Nef at a negative value, and using the power generated by the first rotor 23 rotating in synchronization with the input shaft 6, the second rotor 24 is rotated and the oil pump 5 is driven. As a result, power is generated in the stator 22 using the power of the input shaft 6, and as shown in FIG. 13, the input shaft rotation speed Nin decreases, and accordingly the pump rotation speed Nop decreases, so that the load on the oil pump 5 can be reduced. In addition, by charging the generated power to the drive battery 32, it can be used as power for the second control and as power to drive other auxiliaries.

[0057] As described above, according to this embodiment, the second electric motor 21 is configured as described above, has the same function as a device combining a planetary gear device and a general one-rotor type electric motor, and is connected to the engine 3, the first electric motor 11, the oil pump 5, and the like as described above. Then, the first control using the power of the input shaft 6 connected to the transmission 4, the second control using the power from the drive battery 32, and the third control using both the power of the input shaft 6 and the power from the drive battery 32 are selectively executed to drive the oil pump 5. Therefore, unlike the conventional device, it is possible to unify the oil pump, thereby reducing the weight of the vehicle, the manufacturing cost and the installation space of the oil pump, and for example, expanding the interior space of the vehicle. In addition, it is possible to suppress the power consumption of the battery compared to the case where the oil pump is always driven by an electric motor connected to the battery.

[0058] Furthermore, the second electric motor 21 can reduce the number of parts and the number of rotor shafts compared to a device that combines a planetary gear set and a one-rotor type electric motor having the same functions. Also, since there is no contact between the rotors (or between the rotating magnetic field and the rotors), it is possible to eliminate friction and rattle caused by meshing of gears in a planetary gear set, power transmission loss between the rotors caused by them, and lubrication of the gears. Furthermore, unlike the rotor of a normal motor, the rotating magnetic field of the stator 22 does not have an inertial mass, so there is no response delay due to inertia when the rotation of the input shaft 6 fluctuates, for example, and the responsiveness of the drive of the oil pump 5 can be improved.

[0059] Furthermore, the second control is executed when the first clutch CL1 provided between the first electric motor 11 and the engine 3 is in a disengaged state and the detected input shaft rotation speed Nin is less than the first threshold value NREF1. As a result, when the transmission of power from the engine 3 to the transmission 4 is interrupted and the actual rotation speed of the input shaft 6 is low and the power is insufficient, the oil pump 5 can be driven using electric power from the drive battery 32. For example, before the vehicle V is driven by the first electric motor 11, the oil pump 5 is driven by the second control and the transmission 4 is started up in advance, thereby enabling the vehicle V to be driven smoothly by the first electric motor 11 thereafter.

[0060] Furthermore, when the oil pump is driven using a planetary gear device in a low-speed state of the vehicle V where the rotation speed of the input shaft 6 is low, gear backlash generates a rattle noise, which is easily heard by the driver, particularly when switching between the third control and the second control, and this may deteriorate marketability. In contrast, in the embodiment, a non-contact type second electric motor 21 without gears is used, which can prevent the rattle noise and improve marketability.

[0061] Furthermore, when the input shaft rotation speed Nin becomes equal to or greater than the first threshold value NREF1 during execution of the second control, the control is switched to the third control. As a result, when the rotation speed of the input shaft 6 increases and the power of the input shaft 6 is sufficiently increased, the power of the input shaft 6 can be effectively used to drive the oil pump 5, and the power consumption of the drive battery 32 can be reduced.

[0062] Furthermore, when the input shaft rotation speed Nin becomes equal to or greater than the second threshold value NREF2, the magnetic field rotation speed of the second electric motor 21 is held at a negative value, and the first control is executed. In this way, when the rotation speed of the input shaft 6 increases significantly, the first control is executed, thereby decreasing the rotation speed of the first rotor 23 and the second rotor 24 of the second electric motor 21, and reducing the load on the oil pump 5. In addition, by charging the electric power generated by the first control to the drive battery 32 or the like, it can be used as electric power for the second control or as electric power for driving other auxiliaries.

[0063] The present invention is not limited to the embodiment described above, and can be embodied in various forms. For example, the configuration of the oil pump drive device shown in FIG. 1 is an example, and the connection relationship between the components and the layout can be changed as appropriate. For example, in the embodiment, the second electric motor 21 and the oil pump 5 are configured as separate bodies, and the second rotor 24 of the second electric motor 21 and the input shaft 5a of the oil pump 5 are connected via the output gear G1 and the input gear G2, but the second electric motor 21 and the oil pump 5 may be configured as an integral body, and the second rotor 24 and the input shaft 5a may be directly connected coaxially. Also, in the embodiment, the rotor 13 of the first electric motor 11 and the first rotor 23 of the second electric motor 21 are directly connected coaxially to the input shaft 6, but these rotors 13, the second rotor 23, and the input shaft 6 may be connected via a drive gear or a sprocket.

[0064] In addition, in the embodiment, the input shaft rotation angle sensor 41 is provided on the input shaft 6, and the pump rotation angle sensor 42 is provided on the input shaft 5a of the oil pump 5. However, since a certain relationship such as that expressed by equation (3) is established between the input shaft rotation speed Nin and the pump rotation speed Nop, one of the two sensors 41, 42 may be omitted.

[0065] In addition, the number of armatures of the stator 22 of the second electric motor 21, the number of magnetic poles of the first rotor 23, and the number of soft magnetic bodies of the second rotor 24 in the embodiment are merely examples, and any combination of numbers can be used as long as it satisfies the conditions described in claim 1. In addition, the detailed configuration can be appropriately changed within the scope of the spirit of the present invention. [Explanation of symbols]

[0066] V Vehicle 2 ECU (control means, clutch status acquisition means) 3. Engine (internal combustion engine) 4-speed 5. Oil pump 11 1st electric motor 13 Rotor 21 2nd electric motor 22 Stator 22a Iron core (armature) 22c U-phase coil (armature) 22d V-phase coil (armature) 22e W-phase coil (armature) 23 First Rotor 23a Permanent magnet (magnetic pole) 24 Second Rotor 24a core (soft magnetic material) 32 Drive battery (battery) 41 Input shaft rotation angle sensor (input shaft rotation speed detection means) CL1 First clutch (clutch) Nin Input shaft speed (input shaft speed) NREF1 First threshold NREF2 Second threshold

Claims

1. A drive device for a vehicle oil pump having an input shaft to which power from a power source is input and which drives an oil pump, a first electric motor having a rotatable rotor connected to the input shaft; A second electric motor connected to the oil pump; and a control means for controlling the second electric motor. the second electric motor includes a stator connected to a battery, a first rotor radially opposed to the stator, rotatable in a circumferential direction, and connected to the input shaft, and a second rotor disposed between the stator and the first rotor, rotatable in the circumferential direction, and connected to the oil pump; the first rotor has a magnetic pole row that is formed of a predetermined number of magnetic poles arranged in the circumferential direction and that is arranged such that each two adjacent magnetic poles have polarities different from each other; the stator is made up of a plurality of armatures arranged in the circumferential direction, and is disposed to face the magnetic pole row, and has an armature row that generates a rotating magnetic field rotating in the circumferential direction between the armature row and the magnetic pole row by a plurality of armature magnetic poles generated in the plurality of armatures, the second rotor is made of a predetermined number of soft magnetic bodies arranged in the circumferential direction at intervals from each other, and has a soft magnetic body row disposed between the magnetic pole row and the armature row; a ratio of the number of the armature magnetic poles to the number of the magnetic poles to the number of the soft magnetic bodies is set to 1:m:(1+m) / 2 (m≠1.0); the control means selectively executes a first control in which the second rotor is rotated and the oil pump is driven using power generated by the first rotor rotating synchronously with the input shaft, a second control in which the second rotor is rotated and the oil pump is driven by supplying electric power from the battery to the stator, and a third control in which the second rotor is rotated and the oil pump is driven using both the power of the first rotor and the electric power supplied from the battery to the stator, The first electric motor is connected to an internal combustion engine via a clutch, A clutch state acquisition means for acquiring an engagement / disengagement state of the clutch; and an input shaft rotation speed detection means for detecting the rotation speed of the input shaft, The control means executes the second control when the clutch disengagement state is detected and the rotation speed of the input shaft is less than a predetermined first threshold, and executes the third control when the rotation speed of the input shaft becomes equal to or greater than the first threshold while the second control is being executed.

2. The drive device for a vehicle oil pump as described in claim 1, characterized in that the control means holds the magnetic field rotation speed of the second motor at a negative value and executes the first control when the rotation speed of the input shaft becomes equal to or greater than a predetermined second threshold value which is greater than the first threshold value.

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