JP6072464B2 - Hydraulic oil supply device - Google Patents

Description

  The present invention relates to a hydraulic fluid supply device that supplies hydraulic fluid to a speed change mechanism between a traveling motor and drive wheels.

  In a hybrid vehicle including an engine and a travel motor, a vehicle has been developed in which a travel motor is provided between the engine and the drive wheel, and a clutch is provided between the engine and the travel motor. In this hybrid vehicle, the engine can be stopped by releasing the clutch, and the driving wheels can be driven using the traveling motor, so that the fuel consumption can be actively suppressed according to the traveling state. It becomes. Further, in this hybrid vehicle, it is necessary to supply hydraulic oil to a transmission mechanism such as a continuously variable transmission or an automatic transmission even during EV traveling when the engine is stopped. Therefore, the electric oil pump that operates even when the engine is stopped Is installed. However, providing the control oil pressure during EV travel only with the electric oil pump leads to an increase in the size of the electric oil pump. Therefore, the electric oil pump is mounted and the rotating shaft on the downstream side (drive wheel side) from the clutch. Has been proposed (see Patent Document 1).

JP 2003-294124 A

  Generally, in a hybrid vehicle equipped with an electric oil pump and a mechanical oil pump, the electric oil pump is supplementarily operated in a low vehicle speed range where the discharge hydraulic pressure of the mechanical oil pump is reduced. That is, when the rotational speed of the mechanical oil pump is lower than the operation threshold with the deceleration travel, the electric oil pump is operated, whereas when the rotational speed of the mechanical oil pump is higher than the stop threshold with the acceleration travel, The electric oil pump is stopped. In order to prevent control hunting in which the operation and stop of the electric oil pump are repeated in a short time, it is important to appropriately set a hysteresis width between the operation threshold and the stop threshold.

  By the way, in a traveling situation in which a disturbance such as a large vehicle body vibration occurs, control hunting is likely to occur due to the disturbance, so it is necessary to set a large hysteresis width. However, setting the hysteresis width large is a factor for delaying the stop timing of the electric oil pump because the stop threshold is raised. That is, setting a large hysteresis width unnecessarily expands the operating range of the electric oil pump and reduces the fuel efficiency of the vehicle.

  An object of the present invention is to narrow the operating region of an electric oil pump while avoiding control hunting of the electric oil pump.

The hydraulic oil supply device of the present invention is a hydraulic oil supply device that is used in a vehicle including a speed change mechanism between a traveling motor and a drive wheel, and supplies the operating oil to the speed change mechanism. A first oil pump that includes a rotor to be coupled and that supplies hydraulic oil to the transmission mechanism; and a rotor that is coupled to an electric motor that is separate from the traveling motor and that supplies hydraulic oil to the transmission mechanism. A two-oil pump, and a pump operation control unit that operates the second oil pump by controlling the electric motor to an energized state when a rotor rotational speed of the first oil pump is lower than an operation threshold as the vehicle travels at a reduced speed. A pump stop control for stopping the second oil pump by controlling the electric motor to a non-energized state when the rotational speed of the rotor of the first oil pump exceeds a stop threshold as the vehicle is accelerated. And parts, wherein the threshold difference between big the stop threshold than the operating threshold value and the activation threshold, have a, a threshold difference setting unit that sets, based on the vehicle acceleration, the threshold difference setting unit, the vehicle acceleration The threshold difference is increased when the absolute value of the vehicle increases, while the threshold difference is decreased when the absolute value of the vehicle acceleration decreases .

Hydraulic oil supply device of the present invention has a stop threshold value setting unit, for setting the stop threshold value by adding the threshold difference to the activation threshold, characterized in that. Hydraulic oil supply device of the present invention, while increasing the activation threshold when the absolute value of the vehicle acceleration increases, having an operating threshold setting unit, decreasing the activation threshold when the absolute value of the vehicle acceleration is reduced , characterized in that. Hydraulic oil supply device of the present invention, the rotor of the first oil pump, the are in traction motor coupled via a power transmission path, characterized in that.

  According to the present invention, since the threshold difference between the operation threshold and the stop threshold is set based on the vehicle acceleration, it becomes possible to suppress the control hunting of the second oil pump in a driving situation where disturbance is likely to occur. It is possible to suppress the operation of the second oil pump in a traveling situation in which disturbance is unlikely to occur.

It is the schematic which shows the power unit mounted in a hybrid vehicle. It is explanatory drawing which shows the operating state of a mechanical oil pump and an electric oil pump. It is a flowchart which shows the setting procedure of an operation threshold value and a stop threshold value, and the control procedure of an electric oil pump. It is a diagram which shows an example of the hysteresis width calculated based on vehicle acceleration. It is explanatory drawing which shows the operating state of an electric oil pump. It is a flowchart which shows the setting procedure of an operation threshold value and a stop threshold value, and the control procedure of an electric oil pump. It is a diagram which shows an example of the action | operation threshold value computed based on vehicle acceleration. It is explanatory drawing which shows the operating state of an electric oil pump.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram showing a power unit 10 mounted on a hybrid vehicle. As shown in FIG. 1, a power unit 10, also called a power train, includes an engine 11 and a motor generator (traveling motor) 12 as power sources. The power unit 10 is provided with a continuously variable transmission 13 as a speed change mechanism. The continuously variable transmission 13 includes a primary pulley 14 and a secondary pulley 15. A crankshaft 17 of the engine 11 is connected to one side of the primary pulley 14 via an electromagnetic clutch 16, and a rotor 18 of the motor generator 12 is connected to the other side of the primary pulley 14. The secondary pulley 15 is connected to drive wheels 21 via a drive wheel output shaft 19 and a differential mechanism 20.

  Thus, the motor generator 12 and the drive wheels 21 are connected via the power transmission path 22 including the continuously variable transmission 13, the drive wheel output shaft 19, the differential mechanism 20, and the like. An electromagnetic clutch 16 that can be switched between a released state and an engaged state is provided between the engine 11 and the power transmission path 22. By releasing the electromagnetic clutch 16, the engine 11 can be disconnected from the power transmission path 22, and the vehicle can be run using only the motor generator 12. On the other hand, by fastening the electromagnetic clutch 16, the engine 11 can be connected to the power transmission path 22, and the vehicle can be driven using the motor generator 12 and the engine 11. In order to switch the electromagnetic clutch 16 between the released state and the engaged state, energization control is performed on the electromagnetic coil 16a of the electromagnetic clutch 16 by a control unit 42 described later.

  The continuously variable transmission 13 has a primary shaft 31 and a secondary shaft 32 that is parallel to the primary shaft 31. A primary pulley 14 is provided on the primary shaft 31, and a primary oil chamber 14 a is defined on the back side of the primary pulley 14. A secondary pulley 15 is provided on the secondary shaft 32, and a secondary oil chamber 15 a is defined on the back side of the secondary pulley 15. Further, a drive chain 33 is wound around the primary pulley 14 and the secondary pulley 15. By adjusting the hydraulic pressures of the primary oil chamber 14a and the secondary oil chamber 15a, the winding groove diameter of the drive chain 33 can be changed by changing the pulley groove width.

  Next, the hydraulic oil supply device 34 that is an embodiment of the present invention will be described. As shown in FIG. 1, the power unit 10 is provided with a mechanical oil pump 35 as a first oil pump, and an electric oil pump 36 as a second oil pump. The mechanical oil pump 35 has an inner rotor (rotor) 35a connected to the motor generator 12 via a chain mechanism 37, and an outer rotor 35b meshing with the inner rotor 35a. The chain mechanism 37 includes a drive sprocket 37a fixed to the motor output shaft 38 of the motor generator 12, a driven sprocket 37b connected to the inner rotor 35a, and a chain 37c wound around the sprockets 37a and 37b. . Thus, since the inner rotor 35a of the mechanical oil pump 35 is connected to the motor output shaft 38 constituting the power transmission path 22, the mechanical oil pump 35 can be driven while the vehicle is traveling. It has become. Further, the inner rotor 35a of the mechanical oil pump 35 rotates at a rotational speed determined by the speed ratio of the continuously variable transmission 13 and the vehicle speed. That is, the flow rate and pressure of the hydraulic oil discharged from the mechanical oil pump 35 are determined according to the gear ratio and the vehicle speed. The electric oil pump 36 includes an inner rotor (rotor) 36a connected to a pump motor (electric motor) 39, and an outer rotor 36b engaged with the inner rotor 36a. In addition, an inverter 40 is connected to the pump motor 39 that is an AC motor. By controlling the current value and frequency of the AC current by the inverter 40, the rotation speed of the pump motor 39, that is, the rotation speed of the inner rotor 36a. Can be controlled. That is, the flow rate and pressure of the hydraulic oil discharged from the electric oil pump 36 are determined according to the rotational speed of the pump motor 39. The illustrated mechanical oil pump 35 and electric oil pump 36 are internal gear type oil pumps, but are not limited to this, and may be external gear type oil pumps.

  Further, in order to supply and control hydraulic oil from the mechanical oil pump 35 and the electric oil pump 36 to the continuously variable transmission 13 and the like, the power unit 10 is provided with a valve body 41 in which a plurality of electromagnetic valves are incorporated. ing. A mechanical oil pump 35 and an electric oil pump 36 are connected to the input port of the valve body 41, and a primary oil chamber 14 a and a secondary oil chamber 15 a are connected to the output port of the valve body 41. In addition, hydraulic control with respect to the continuously variable transmission 13 is possible by controlling each solenoid valve in the valve body 41 by a control unit 42 described later.

  In order to control the engine 11, the motor generator 12, the continuously variable transmission 13, the electromagnetic clutch 16, and the like, a control unit 42 is provided in the hybrid vehicle. The control unit 42 includes an ignition switch 44 that is operated by the driver when the system is started up, an accelerator opening sensor 45 that detects the operating state of the accelerator pedal, a vehicle speed sensor 46 that detects the rotational speed of the drive wheels 21, and an engine speed. An engine speed sensor 47 for detecting, an inhibitor switch 48 for detecting the operation state of the select lever, a rotor speed sensor 49 for detecting the rotor speed MN of the inner rotor 35a of the mechanical oil pump 35, and the like are connected. In the following description, the rotor rotational speed MN of the mechanical oil pump 35 is described as the rotor rotational speed MN. The control unit 42 determines the vehicle state based on information from various sensors and outputs control signals to the engine 11, the motor generator 12, the electromagnetic clutch 16, the valve body 41, and the like. The control unit 42 includes a CPU that calculates control signals and the like, and also includes a ROM that stores control programs, arithmetic expressions, map data, and the like, and a RAM that temporarily stores data.

  Next, the supply state of hydraulic oil to the valve body 41 from the mechanical oil pump 35 and the electric oil pump 36 will be described. Here, FIG. 2 is an explanatory view showing the operating state of the mechanical oil pump 35 and the electric oil pump 36. FIG. 2 shows a state in which the transmission ratio of the continuously variable transmission 13 is kept constant, that is, a state in which the rotor rotational speed MN of the mechanical oil pump 35 is linked only to the vehicle speed.

  As shown in FIG. 2, when the vehicle travels at a reduced speed, the rotor rotational speed MN decreases in conjunction with the vehicle speed, so the discharge hydraulic pressure Pm of the mechanical oil pump 35 also decreases in conjunction with the vehicle speed. When the rotor rotational speed MN falls below a predetermined operation threshold value EPon (symbol α), an operation signal is output to the inverter 40 from the control unit 42 that functions as a pump operation control unit. As a result, the pump motor 39 of the electric oil pump 36 is controlled to be energized, and the discharge hydraulic pressure Pe of the electric oil pump 36 is raised so as to compensate for the decrease in the discharge hydraulic pressure Pm. In this way, by operating the electric oil pump 36 in accordance with the decrease in the vehicle speed, the hydraulic oil supply hydraulic pressure P1 to the valve body 41 can be maintained above the lower limit hydraulic pressure PL, and the continuously variable transmission 13 can be operated normally. It can be activated.

  On the other hand, when the vehicle shifts from the stop state to the acceleration running in which the vehicle speed increases, the rotor rotational speed MN increases in conjunction with the vehicle speed, so that the discharge hydraulic pressure Pm of the mechanical oil pump 35 also increases in conjunction with the vehicle speed. When the rotor rotational speed MN exceeds a predetermined stop threshold value EPoff (symbol β), a stop signal is output from the control unit 42 functioning as a pump stop control unit to the inverter 40, and the pump motor 39 of the electric oil pump 36 is activated. Controlled to a non-energized state. As described above, by stopping the electric oil pump 36 in accordance with the increase in the vehicle speed, it is possible to suppress power consumption for driving the electric oil pump 36 and improve the fuel efficiency of the hybrid vehicle. . Further, in order to avoid control hunting in which the operation and stop of the electric oil pump 36 are repeated in a short time, the operation threshold value EPon and the stop threshold value EPoff are set apart by a hysteresis width hys as a threshold difference. In the following description, the hysteresis width hys is abbreviated as “his width hys”.

  Subsequently, after describing the setting procedure of the operation threshold value EPon and the stop threshold value EPoff by the control unit 42, the control procedure of the electric oil pump 36 will be described. Here, FIG. 3 is a flowchart showing a procedure for setting the operation threshold value EPon and the stop threshold value EPoff and a control procedure for the electric oil pump 36. As shown in FIG. 3, in step S <b> 1, the longitudinal vehicle acceleration is calculated based on the rotational speed of the drive wheel 21. In subsequent step S2, a hysteresis width hys is calculated based on the vehicle acceleration. Here, FIG. 4 is a diagram showing an example of the hysteresis width hys calculated based on the vehicle acceleration. As shown in FIG. 4, when the vehicle acceleration is greatly calculated on the acceleration side (positive side), or when the vehicle acceleration is largely calculated on the deceleration side (negative side), the hysteresis width hys is also calculated large. . On the other hand, when the vehicle acceleration is calculated to be small on the acceleration side or when the vehicle acceleration is calculated to be small on the deceleration side, the hysteresis width hys is also calculated to be small. That is, the control unit 42 functioning as a threshold difference setting unit increases the hysteresis width hys when the absolute value of the vehicle acceleration increases, while setting the hysteresis width hys when the absolute value of the vehicle acceleration decreases. Is set to decrease. In the case shown in FIG. 4, the hysteresis width hys is set along the quadratic curve. However, the hysteresis width hys is not limited to this, and the hysteresis width hys may be set along the straight line. In the case shown in FIG. 4, the size of the hysteresis width hys is set to be the same on the acceleration side and the deceleration side. However, the present invention is not limited to this, and the size of the hysteresis width hys is set to the acceleration side. It may be changed on the deceleration side.

  As described above, when the hysteresis width hys is calculated in step S2, in the subsequent step S3, the stop threshold EPoff is calculated by adding the hysteresis width hys to the preset operation threshold value EPon. As described above, the control unit 42 functioning as the stop threshold value setting unit sets the stop threshold value EPoff based on the operation threshold value EPon. Subsequently, in step S4, the rotor rotational speed MN of the mechanical oil pump 35 is read. In step S5, it is determined whether or not the rotor rotational speed MN is below the stop threshold value EPoff. If it is determined in step S5 that the rotor rotational speed MN is equal to or greater than the stop threshold value EPoff, the process proceeds to step S6, and the operation permission flag FLG of the electric oil pump 36 is canceled. On the other hand, when it is determined in step S5 that the rotor rotational speed MN is lower than the stop threshold value EPoff, the process proceeds to step S7, and it is determined whether or not the rotor rotational speed MN is lower than the operation threshold value EPon. If it is determined in step S7 that the rotor rotational speed MN is below the operation threshold value EPon, the process proceeds to step S8, and the operation permission flag FLG is set. On the other hand, if it is determined in step S7 that the rotor rotational speed MN is greater than or equal to the stop threshold value EPoff, the process proceeds to step S9, and the previous operation permission flag FLG is held. In a succeeding step S10, it is determined whether or not the operation permission flag FLG is set. If it is determined in step S10 that the operation permission flag FLG is set, the process proceeds to step S11, where the pump motor 39 is controlled to be in an energized state and the drive of the electric oil pump 36 is started. On the other hand, if it is determined in step S10 that the operation permission flag FLG is released, the process proceeds to step S12, where the pump motor 39 is controlled to be in a non-energized state and the electric oil pump 36 is stopped.

  Next, the effect when the hysteresis width hys is increased or decreased based on the vehicle acceleration will be described. FIG. 5 is an explanatory view showing the operating state of the electric oil pump 36. As shown in FIG. 5, the control unit 42 determines the vehicle acceleration based on the vehicle speed, and then sets the hysteresis width hys based on the vehicle acceleration. Further, the control unit 42 sets the stop threshold value EPoff by adding the hysteresis width hys to the preset operation threshold value EPon. As described above, by increasing or decreasing the hysteresis width hys according to the vehicle acceleration, it is possible to narrow the operating region of the electric oil pump 36 while preventing the control hunting of the electric oil pump 36. That is, the hysteresis width hys is set to be large during sudden deceleration or rapid acceleration with a large absolute value of the vehicle acceleration, that is, in a traveling situation in which disturbance such as vehicle body vibration is likely to occur. For this reason, as indicated by the symbol Z, even when noise affects the rotor speed MN due to disturbance, the rotor speed MN does not exceed the stop threshold value EPoff immediately after the rotor speed MN falls below the operating threshold value EPon. Control hunting of the oil pump 36 can be prevented. On the other hand, the hysteresis width hys is set to be small during slow deceleration or slow acceleration with a small absolute value of the vehicle body acceleration. As a result, the stop threshold EPoff can be set low and the stop timing of the electric oil pump 36 can be set at the time of slow deceleration or slow acceleration at which disturbances such as body vibrations are unlikely to occur, that is, in a driving situation where control hunting is difficult to occur. Can be accelerated (symbol α). Therefore, as indicated by the symbol β, from the viewpoint of preventing control hunting that may occur during sudden deceleration or sudden acceleration, compared to the case where the hysteresis width hys is always set large, that is, the stop threshold value Xoff is always set high. Thus, the stop timing of the electric oil pump 36 can be greatly advanced. As a result, the operating region of the electric oil pump 36 can be narrowed, and power consumption of the electric oil pump 36 can be suppressed to improve fuel efficiency.

  In the above description, the operation threshold value EPon is set to a preset value. However, the present invention is not limited to this, and the operation threshold value EPon may be set based on the vehicle acceleration. Here, FIG. 6 is a flowchart showing a procedure for setting the operation threshold value EPon and the stop threshold value EPoff and a control procedure for the electric oil pump 36. In FIG. 6, the same steps as those shown in FIG. 3 are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 6, in step S1, the vehicle acceleration in the front-rear direction is calculated based on the rotational speed of the drive wheel 21, and in step S2, the hysteresis width hys is calculated based on the vehicle acceleration. In step S20, the operation threshold value EPon is set based on the vehicle acceleration. Here, FIG. 7 is a diagram showing an example of the operation threshold value EPon calculated based on the vehicle acceleration. As shown in FIG. 7, when the vehicle acceleration is largely calculated on the acceleration side (positive side) or when the vehicle acceleration is largely calculated on the deceleration side (negative side), the operation threshold value EPon is also calculated large. . On the other hand, when the vehicle acceleration is calculated to be small on the acceleration side, or when the vehicle acceleration is calculated to be small on the deceleration side, the operation threshold value EPon is also calculated to be small. That is, when the absolute value of the vehicle acceleration increases, the control unit 42 that functions as the operation threshold setting unit increases and sets the operation threshold value EPon, whereas when the absolute value of the vehicle acceleration decreases, the control threshold value EPon. Is set to decrease. In the case shown in FIG. 7, the operation threshold value EPon is set along the quadratic curve, but the present invention is not limited to this, and the operation threshold value EPon may be set along the straight line. Further, in the case shown in FIG. 7, the magnitude of the operation threshold value EPon is set to be the same on the acceleration side and the deceleration side. It may be changed on the deceleration side.

  As described above, when the hysteresis width hys and the operation threshold value EPon are set based on the vehicle acceleration, in the subsequent step S3, the hysteresis width hys is added to the operation threshold value EPon to calculate the stop threshold value EPoff. In step S4 and subsequent steps, the electric oil pump 36 is controlled based on the operation threshold value EPon and the stop threshold value EPoff. Here, FIG. 8 is an explanatory view showing an operating state of the electric oil pump 36. FIG. 8 shows a traveling situation similar to FIG. As shown in FIG. 8, when the absolute value of the vehicle acceleration increases, the operation threshold value EPon is also set to increase, and when the absolute value of the vehicle acceleration decreases, the operation threshold value EPon is also set to decrease. . In this way, by increasing or decreasing the operation threshold value EPon according to the absolute value of the vehicle acceleration, it is possible to avoid insufficient supply of hydraulic oil to the continuously variable transmission 13 and to narrow the operating range of the electric oil pump 36. Become.

  That is, during sudden deceleration with a large absolute value of the vehicle acceleration, the discharge hydraulic pressure Pm of the mechanical oil pump 35 rapidly decreases, and there is a risk of insufficient supply of hydraulic oil to the continuously variable transmission 13 or the like. For this reason, at the time of sudden deceleration, the operating threshold value EPon is raised according to the vehicle acceleration, so that the electric oil pump 36 is operated quickly to avoid insufficient supply of hydraulic oil. Similarly, during sudden acceleration with a large absolute value of the vehicle acceleration, hydraulic oil is discharged from the mechanical oil pump 35 with a delay with respect to the rapidly changing rotor rotational speed MN. Supply shortage may occur. For this reason, at the time of rapid acceleration, the stop threshold value EPoff is raised by raising the operation threshold value EPon according to the absolute value of the vehicle acceleration. Thereby, the electric oil pump 36 can be operated for a long time, and it becomes possible to avoid insufficient supply of hydraulic oil.

  Further, at the time of slow deceleration with a small absolute value of the vehicle acceleration, the discharge hydraulic pressure Pm of the mechanical oil pump 35 gradually decreases, so that there is no shortage of supply of hydraulic oil to the continuously variable transmission 13 and the like. The operation timing of 36 can be delayed. For this reason, at the time of slow deceleration, the operation threshold value EPon is lowered according to the absolute value of the vehicle acceleration, thereby delaying the operation timing of the electric oil pump 36 and improving the fuel consumption performance. Similarly, at the time of slow acceleration with a small absolute value of the vehicle acceleration, the hydraulic oil is discharged from the mechanical oil pump 35 with a good response to the slowly changing rotor rotational speed MN. It is possible to advance the stop timing of the electric oil pump 36 without causing a shortage of supply. For this reason, at the time of slow acceleration, the stop threshold value EPoff is lowered by lowering the operation threshold value EPon according to the vehicle acceleration. As a result, the fuel oil performance can be improved by advancing the stop timing of the electric oil pump 36.

  It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. In the above description, the continuously variable transmission 13 is employed as the transmission mechanism, but the present invention is not limited to this, and a planetary gear type or parallel shaft type automatic transmission may be employed as the transmission mechanism. In the above description, the vehicle acceleration is calculated using the rotational speed of the drive wheel 21, but the present invention is not limited to this, and the vehicle acceleration may be detected using an acceleration sensor. Alternatively, the vehicle acceleration may be calculated using the rotational speed of the members constituting 22. Furthermore, in the above description, the rotor rotational speed sensor 49 is used to detect the rotor rotational speed MN of the mechanical oil pump 35. The number MN may be calculated.

  In the above description, the mechanical oil pump 35 is connected to the motor output shaft 38. However, the mechanical oil pump 35 is not limited to this, and the mechanical oil pump 35 is connected to the power transmission path 22 such as the primary shaft 31, the secondary shaft 32, and the drive wheel output shaft 19. A mechanical oil pump 35 may be connected. The mechanical oil pump 35 is connected to the motor output shaft 38 via the chain mechanism 37, but the present invention is not limited to this, and the mechanical oil pump 35 is connected using a belt mechanism or a gear train. May be. Further, the inner rotor 35a of the mechanical oil pump 35 may be directly fixed to the primary shaft 31, the secondary shaft 32, the drive wheel output shaft 19 and the like constituting the power transmission path 22. Further, the pump type of the mechanical oil pump 35 or the electric oil pump 36 may be a gear pump such as a trochoid pump or an involute gear pump, or may be a vane pump in which a plurality of vanes are provided radially on the rotor. .

  In the above description, the electromagnetic clutch 16 is provided between the engine 11 and the continuously variable transmission 13. However, the present invention is not limited to this, and a hydraulic clutch is provided between the engine 11 and the continuously variable transmission 13. May be. Further, the clutch type may be a friction clutch or a meshing clutch. In the above description, the pump motor 39 is inverter-controlled. However, the present invention is not limited to this, and the pump motor 39 may be simply switched between an energized state and a non-energized state. The illustrated pump motor 39 is an AC motor, but any type of electric motor may be used as the pump motor 39. Furthermore, although the illustrated motor generator 12 is an AC motor such as a permanent magnet synchronous motor, it goes without saying that any type of electric motor may be used as the motor generator 12.

12 Motor generator (traveling motor)
13 Continuously variable transmission (transmission mechanism)
21 Drive wheel 22 Power transmission path 34 Hydraulic oil supply device 35 Mechanical oil pump (first oil pump)
35a Inner rotor (rotor)
36 Electric oil pump (second oil pump)
36a Inner rotor (rotor)
39 Pump motor (electric motor)
42 control unit (pump operation control unit, pump stop control unit, threshold difference setting unit, stop threshold setting unit, operation threshold setting unit)
MN Rotor speed (rotor speed)
EPon operation threshold value EPoff stop threshold value hys hysteresis width (threshold difference)

Claims (4)

A hydraulic oil supply device that is used in a vehicle including a transmission mechanism between a traveling motor and a drive wheel and supplies hydraulic oil to the transmission mechanism,
A first oil pump comprising a rotor coupled to the travel motor, and supplying hydraulic oil to the transmission mechanism;
A second oil pump that includes a rotor coupled to an electric motor separate from the travel motor, and that supplies hydraulic oil to the transmission mechanism;
A pump operation control unit configured to control the electric motor to an energized state to operate the second oil pump when the rotor rotation speed of the first oil pump is lower than an operation threshold as the vehicle decelerates;
A pump stop control unit for controlling the electric motor to a non-energized state to stop the second oil pump when the rotor rotation speed of the first oil pump exceeds a stop threshold with acceleration travel;
A threshold difference setting unit that sets a threshold difference between the operation threshold and the stop threshold larger than the operation threshold based on vehicle acceleration ;
I have a,
The threshold difference setting unit increases the threshold difference when the absolute value of the vehicle acceleration increases, and decreases the threshold difference when the absolute value of the vehicle acceleration decreases. apparatus. In the hydraulic oil supply device according to claim 1 Symbol placement,
Wherein the threshold difference is added to the activation threshold having a stop threshold value setting unit, for setting the stop threshold value, the hydraulic oil supply device, characterized in that. The hydraulic oil supply device according to claim 1 or 2 ,
While increasing the activation threshold when the absolute value of the vehicle acceleration increases, having an operating threshold setting unit, decreasing the activation threshold when the absolute value of the vehicle acceleration is decreased, the hydraulic oil supply, characterized in that apparatus. The hydraulic fluid supply apparatus according to any one of claims 1 to 3 ,
The rotor of the first oil pump, the are in traction motor coupled via a power transmission path, the hydraulic oil supply device, characterized in that.

Images