JP2007002933A - Hydraulic controller, shift controller, and vehicle controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize an optimum hydraulic control when an oil pump is switched in a hydraulic controller controlling a hydraulic drive part by switching the operations of an engine-driven oil pump and a motor-driven oil pump as necessary. <P>SOLUTION: In this hydraulic controller, when an operation is switched from the engine-driven oil pump (first oil pump) to the motor-driven oil pump (second oil pump), the second oil pump is driven before the first oil pump is stopped to increase its hydraulic pressure. Accordingly, the synthetic oil pressures of both oil pumps can be prevented from dropping immediately after the switching to maintain necessary original pressures. As a result, the optimum hydraulic control can be realized when the oil pumps are switched. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hydraulic control device, a shift control device, and a vehicle control device that switch the operation of an engine-driven oil pump and a motor-driven oil pump as necessary to control a hydraulic drive unit.

  In recent years, hybrid vehicles have been developed for the purpose of improving fuel consumption and reducing exhaust gas. This hybrid vehicle includes an engine consisting of an internal combustion engine as a power source and an electromagnetically driven motor generator. For example, when a sudden torque is required, such as when starting, or when driving in a city or in a traffic jam When the vehicle runs at a low speed, it is mainly driven by a motor, and when the vehicle runs at a low load, it is driven mainly by an engine. When there is a large acceleration demand, both the engine and the motor are driven, and at the time of predetermined deceleration, the power input from the drive wheels is transmitted to the motor generator to operate it as a generator, and its regenerative energy Or charging the vehicle battery as electrical energy.

By the way, in such a hybrid vehicle, for example, a continuously variable transmission that is operated by hydraulic control is mounted, and the hydraulic pressure for the control is supplied by an engine-driven oil pump. Since the engine is stopped, it is necessary to secure a hydraulic pressure source even when the engine is stopped. Accordingly, for example, a first oil pump driven by the engine, a second oil pump driven by the motor, and switching means for switching between these operations are provided, and the first oil pump is mainly operated when the engine is driven, and mainly the second oil pump when the engine is stopped. The hydraulic pressure source has been secured by operating (see, for example, Patent Document 1).
JP 2001-280458 A

  However, when such an oil pump is switched, the hydraulic pressure of the newly driven oil pump does not immediately rise, so that the hydraulic pressure of the hydraulic oil as a whole may decrease, and optimal hydraulic control may not be realized.

  FIG. 12 is a timing chart showing a control state of the oil pump by the conventional hydraulic control device. The horizontal axis of the figure represents the passage of time, and the vertical axis represents the hydraulic pressure of the first oil pump, the hydraulic pressure of the second oil pump, and the combined hydraulic pressure from the top. In the figure, a solid line represents an output instruction value, and a broken line represents an actual output value (referred to as “actual output value”).

  That is, the output instruction value of the first oil pump and the second oil pump is switched stepwise at the time of switching, but each oil pump is caused by a delay in response of the mechanical structure, a time delay of the hydraulic oil flowing through the oil passage, and the like. The actual output value due to changes gently. As a result, immediately after the switching point, there is a portion where the combined oil pressure is slightly lower than the output instruction value (virtual output instruction value combining the output instruction values of both oil pumps: hereinafter also referred to as “target oil pressure”). Arise. For this reason, in some cases, the original pressure of the hydraulic control device installed on the downstream side cannot be generated, and optimal hydraulic control of the continuously variable transmission cannot be realized, and drivability due to deterioration of fuel consumption, shift shock, etc. There has been a problem of incurring a decline.

  The present invention has been made in view of the above points, and in an oil pressure control apparatus for controlling the oil pressure drive unit by switching the operation of an engine-driven oil pump and a motor-driven oil pump as necessary, the oil pump An object of the present invention is to provide an optimal hydraulic control at the time of switching, and to provide a shift control device and a vehicle control device capable of realizing stable shift control and vehicle control by the optimal hydraulic control.

  In order to solve the above problems, the present invention is a hydraulic control device that controls a hydraulic drive unit that is hydraulically driven, and is driven by hydraulic oil supplied from a first oil pump driven by an engine and an electric motor. Hydraulic control means for controlling the hydraulic pressure supplied to the hydraulic drive unit using at least one of the hydraulic oil supplied from the second oil pump, and driving and controlling the first oil pump and the second oil pump, When switching the drive from one oil pump to the other oil pump, there is provided a pump drive control means for driving the other oil pump and stopping the drive of the one oil pump after a predetermined period of time. A hydraulic control device is provided.

  According to such a hydraulic control device, when switching from the engine-driven first oil pump to the motor-driven second oil pump, the second oil pump is driven in advance before the first oil pump is stopped, Hydraulic pressure is increased. Conversely, when switching from the second oil pump to the first oil pump, the first oil pump is driven in advance before the second oil pump is stopped, and the hydraulic pressure is increased.

  For this reason, the combined hydraulic pressure of both oil pumps can be prevented or suppressed from dropping immediately after switching, and the hydraulic pressure to be supplied to the hydraulic drive unit can be ensured. Note that even if the combined hydraulic pressure becomes higher than the hydraulic pressure to be supplied by the oil pump, there is no problem because the hydraulic pressure supplied to the hydraulic drive unit is controlled by the hydraulic control means.

  Further, in the present invention, a hydraulic control device that controls a hydraulic drive unit that is hydraulically driven, hydraulic oil supplied from a first oil pump driven by an engine, and a second oil pump driven by an electric motor Hydraulic control means for controlling the hydraulic pressure supplied to the hydraulic drive unit using at least one of the hydraulic oil supplied from the first hydraulic pump, and driving control of the first oil pump and the second oil pump. And a pump drive control means for setting the target hydraulic pressure immediately after switching by the other oil pump to be higher than the hydraulic pressure at the time of switching after switching to the other oil pump. A hydraulic control device is provided.

  According to such a hydraulic control device, when switching from the engine-driven first oil pump to the motor-driven second oil pump, the target hydraulic pressure immediately after switching by the second oil pump is necessary at the steady state after switching. Higher than normal oil pressure. Conversely, when switching from the second oil pump to the first oil pump, the target hydraulic pressure immediately after switching by the first oil pump is set to be higher than the hydraulic pressure required during steady state after switching.

  For this reason, the hydraulic pressure of the oil pump to be driven after switching can be quickly raised, and the combined hydraulic pressure immediately after switching between the two oil pumps becomes relatively high. For this reason, the hydraulic pressure to be supplied to the hydraulic drive unit can be secured.

  According to the present invention, there is also provided a shift control device that controls a transmission having a hydraulic drive unit that is hydraulically driven, and is driven by hydraulic oil supplied from a first oil pump driven by an engine and an electric motor. By generating at least one of the hydraulic oils supplied from the second oil pump and generating a hydraulic pressure controlled using the original pressure to the hydraulic drive unit, a transmission gear ratio of the transmission and And / or shift control means for controlling the engagement of the clutch and the first oil pump and the second oil pump, and when switching the drive from one oil pump to the other oil pump, Provided is a speed change control device comprising a pump drive control means for driving the oil pump and stopping the drive of the one oil pump after a predetermined period of time has elapsed. It is.

  According to such a shift control device, the original pressure is generated using the hydraulic oil supplied from the first oil pump or the second oil pump, and the controlled oil pressure is reduced by further reducing the original pressure. By being supplied to the drive unit, predetermined shift control is executed. When the engine is stopped and switched from the first oil pump to the second oil pump, the second oil pump is driven in advance before the first oil pump is stopped, and the hydraulic pressure is increased. Conversely, when the second oil pump is switched to the first oil pump, for example, when the engine is restarted, the first oil pump is driven in advance before the second oil pump is stopped, and the hydraulic pressure is increased. .

  For this reason, the combined hydraulic pressure of both oil pumps can be prevented or suppressed from dropping immediately after switching, and the hydraulic pressure to be supplied to the hydraulic drive unit can be ensured. As a result, the shift control means can perform stable shift control even when the oil pump is switched.

  According to the present invention, there is also provided a shift control device that controls a transmission having a hydraulic drive unit that is hydraulically driven, and is driven by hydraulic oil supplied from a first oil pump driven by an engine and an electric motor. By generating at least one of the hydraulic oils supplied from the second oil pump and generating a hydraulic pressure controlled using the original pressure to the hydraulic drive unit, a transmission gear ratio of the transmission and And / or shift control means for controlling the engagement of the clutch and the first oil pump and the second oil pump, and when switching the drive from one oil pump to the other oil pump, And a pump drive control means for setting a target hydraulic pressure immediately after the switching by the oil pump to be higher than a normal hydraulic pressure after the switching. There is provided.

  Also in such a shift control device, the original pressure is generated using the hydraulic oil supplied from the first oil pump or the second oil pump, and the hydraulic pressure controlled by further reducing the original pressure is hydraulically driven. By being supplied to the unit, predetermined shift control is executed. When the engine is stopped and the first oil pump is switched to the second oil pump, the target hydraulic pressure immediately after the switching by the second oil pump is set higher than the hydraulic pressure required at the steady state after the switching. The Conversely, when switching from the second oil pump to the first oil pump, for example, when the engine is restarted, the target hydraulic pressure immediately after switching by the first oil pump is greater than the hydraulic pressure required during steady state after switching. Set high.

  For this reason, the hydraulic pressure of the oil pump to be driven after switching can be quickly raised, and the combined hydraulic pressure immediately after switching between the two oil pumps becomes relatively high. For this reason, the hydraulic pressure to be supplied to the hydraulic drive unit can be secured. As a result, the shift control means can perform stable shift control even when the oil pump is switched.

  Further, according to the present invention, a transmission having a hydraulic drive unit that is hydraulically driven, a first oil pump that is driven by an engine and supplies hydraulic oil to the hydraulic drive unit, and is driven by an electric motor to generate the hydraulic pressure. A second oil pump that supplies hydraulic oil to the drive unit, and a hydraulic pressure that is supplied to the hydraulic drive unit using the hydraulic oil supplied from at least one of the first oil pump and the second oil pump. When controlling the drive of the hydraulic control means, the first oil pump and the second oil pump, and switching the drive from one oil pump to the other oil pump, the other oil pump is driven for a predetermined period. There is provided a vehicle control device comprising pump drive control means for stopping the drive of the one oil pump after elapse of time.

  According to such a vehicle control device, the oil pump that supplies the hydraulic pressure toward the hydraulic drive unit of the transmission is configured by two types, that is, a first oil pump driven by the engine and a second oil pump driven by the motor. Depending on the running state, it can be switched appropriately. When the engine is stopped and switched from the first oil pump to the second oil pump, the second oil pump is driven in advance before the first oil pump is stopped, and the hydraulic pressure is increased. Conversely, when the second oil pump is switched to the first oil pump, for example, when the engine is restarted, the first oil pump is driven in advance before the second oil pump is stopped, and the hydraulic pressure is increased. .

  For this reason, the combined hydraulic pressure of both oil pumps can be prevented or suppressed from dropping immediately after switching, and the hydraulic pressure to be supplied to the hydraulic drive unit can be ensured. As a result, stable shift control, and hence stable vehicle control, is realized even when the oil pump is switched.

  Further, in the present invention, a transmission having a hydraulic drive unit that is hydraulically driven, a first oil pump that is driven by an engine and supplies hydraulic oil to the hydraulic drive unit, and is driven by an electric motor to generate the hydraulic pressure. A second oil pump that supplies hydraulic oil to the drive unit, and a hydraulic pressure that is supplied to the hydraulic drive unit using the hydraulic oil supplied from at least one of the first oil pump and the second oil pump. The hydraulic pressure control means for controlling the driving of the first oil pump and the second oil pump, and when switching the driving from one oil pump to the other oil pump, the target hydraulic pressure immediately after switching by the other oil pump There is provided a vehicle control apparatus comprising: a pump drive control unit that sets the hydraulic pressure higher than the normal hydraulic pressure after switching.

  Also in such a vehicle control device, the oil pump that supplies the hydraulic pressure toward the hydraulic drive unit of the transmission is configured by two types, a first oil pump driven by the engine and a second oil pump driven by the motor. It is appropriately switched depending on the traveling state. When the engine is stopped and the first oil pump is switched to the second oil pump, the target hydraulic pressure immediately after the switching by the second oil pump is set higher than the hydraulic pressure required at the steady state after the switching. The Conversely, when switching from the second oil pump to the first oil pump, for example, when the engine is restarted, the target hydraulic pressure immediately after switching by the first oil pump is greater than the hydraulic pressure required during steady state after switching. Set high.

  For this reason, the hydraulic pressure of the oil pump to be driven after switching can be quickly raised, and the combined hydraulic pressure immediately after switching between the two oil pumps becomes relatively high. For this reason, even when the oil pump is switched, the hydraulic pressure to be supplied to the hydraulic drive unit can be ensured, and stable shift control and thus stable vehicle control can be realized.

  According to the hydraulic control device of the present invention, it is possible to secure the hydraulic pressure to be supplied by the oil pump driven after the switching by increasing the combined hydraulic pressure immediately after the switching of the oil pump. Hydraulic control can be realized.

  According to the transmission control device of the present invention, by increasing the combined hydraulic pressure immediately after the oil pump is switched, it is possible to secure the hydraulic pressure to be supplied by the oil pump that is driven after the switching. Shift control can be realized.

  In addition, according to the vehicle control device of the present invention, since the combined hydraulic pressure immediately after the oil pump switching is increased, the hydraulic pressure to be supplied by the oil pump driven after the switching can be ensured. Sometimes stable vehicle control can be realized.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
In the present embodiment, the speed change control device of the present invention is applied to a hybrid vehicle (hereinafter simply referred to as “vehicle”) driven by an engine composed of an internal combustion engine and an electromagnetically driven motor generator. FIG. 1 is a system configuration diagram showing the configuration of the vehicle control device according to the first embodiment.

  The vehicle control device includes an engine 2 that drives the front wheels 1 of the vehicle, and a motor generator 4 that drives the rear wheels 3. The engine 2 can be temporarily stopped in a predetermined operating state. On the other hand, the motor generator 4 can function as a motor when the vehicle is driven, and can function as a generator when the vehicle is braked.

  One output shaft of the engine 2 is connected to a mechanical oil pump 5, a torque converter 6, a forward / reverse clutch 7, a continuously variable transmission 8, and a reduction gear 9, and the output of the reduction gear 9 outputs a differential 10. To the left and right front wheels 1.

  The torque converter 6 is for smoothly transmitting the power of the engine 2 to the axle. The pump impeller connected to the output shaft of the engine 2, the turbine liner connected to the output shaft of the torque converter 6, between these And a stator that changes the flow of oil inside and a lock-up clutch that fastens the pump impeller and the turbine liner according to predetermined conditions.

  The forward / reverse clutch 7 includes a planetary gear, and includes a sun gear coupled to the output shaft of the torque converter 6, a carrier coupled to the input shaft of the continuously variable transmission 8, and a ring gear coupled to the brake.

  The continuously variable transmission 8 includes a primary pulley 11 connected to the input shaft, a secondary pulley 12 connected to the output shaft, and a belt 13 stretched between the pulleys, and torque transmitted from the input shaft. Is transmitted to the output shaft. The shift control of the continuously variable transmission 8 is performed by hydraulic control by the hydraulic circuit 14. The hydraulic circuit 14 is driven by the oil pump 5 (corresponding to “first oil pump”) driven by the engine 2 or the oil pump 16 (corresponding to “second oil pump”) driven by the electric motor 15. Hydraulic control is performed using hydraulic oil pumped up from the oil tank. Then, the groove width of the primary pulley 11 is changed by hydraulic control, while the clamping pressure of the secondary pulley 12 on the belt 13 is held by hydraulic control, and the engagement diameter of the belt 13 in each pulley is changed, whereby the input shaft The gear ratio, which is the ratio of the number of rotations between the motor and the output shaft, is continuously changed. In the present embodiment, the primary pulley 11 and the secondary pulley 12 correspond to the “hydraulic drive unit”.

  The reduction gear 9 makes the rotation direction of the axle coincide with the rotation direction of the output shaft of the engine 2. That is, in the continuously variable transmission 8, the rotation direction is reversed between the input shaft and the output shaft, but the reduction gear 9 further reverses the rotation direction of the reversed output shaft to rotate the input shaft. To match.

  The differential 10 transmits the output of the reduction gear 9 to the accelerator shafts connected to the left and right front wheels 1 respectively, and absorbs the rotational difference between the left and right front wheels 1 when the vehicle travels a curve, thereby realizing a smooth running of the vehicle. Let

  The other output shaft of the engine 2 is connected in parallel with a motor generator 21 for power generation and an alternator 22 that is a vehicle AC generator via a predetermined rotating belt. The motor generator 21 generates power using the power of the engine 2 and supplies power to the motor generator 4 and charges each battery described later. The electric power generated by the alternator 22 is supplied to various auxiliary machines such as a vehicle air conditioner and lighting equipment (not shown). When surplus power is generated, the electric power is supplied to the auxiliary battery 23 for auxiliary equipment and charged. Is done.

  Further, an HV battery 24 for supplying electric power to the motor generator 4 as necessary is provided. An inverter unit 27 including a DC-DC converter 25 and various inverters 26 is provided at the center of the motor generator 4, the motor generator 21, the alternator 22, and the HV battery 24. The electric power generated by each generator and the electric power supplied from each battery are supplied to each control target by being transformed to a predetermined voltage via the inverter unit 27, and the electric power generated by each generator is It can be used to charge each battery.

  Each control object is controlled by an electronic control unit (hereinafter referred to as “ECU”). That is, vehicle control including engine control and shift control is performed by the vehicle control ECU 31. The vehicle control ECU 31 is provided with an engine control unit 32 that executes engine control and a shift control unit 33 that executes shift control. Further, the battery ECU 34 performs charge / discharge control of the HV battery 24. Further, a hybrid control ECU (hereinafter referred to as “HVECU”) 35 switches a plurality of travel modes to be described later for engine driving (front wheel driving), motor driving (rear wheel driving), four wheel driving, braking / regeneration, and the like. The various arithmetic processes are performed, and an operation command is output to each ECU.

  Each of the ECUs described above is an independent electronic control unit that is configured around a calculation unit including a microcomputer. Each ECU includes a CPU (Central Processing Unit) that executes various arithmetic processes, a ROM (Read Only Memory) that stores various control arithmetic programs and data, and a RAM (Random) that stores numerical values and flags of arithmetic processes in a predetermined area. Access Memory), EEPROM (Electronically Erasable and Programmable Read Only Memory), which is a non-volatile storage device that stores the results of arithmetic processing, and A / D (Analog / Digital) that converts an input analog signal into a digital signal It includes a converter, an input / output interface through which various digital signals are input / output, a timer for timing used in the calculation process, and a bus line to which these devices are connected. Each ECU has a built-in communication control unit for performing communication processing with each other via a communication line.

  The engine control unit 32 of the vehicle control ECU 31 includes an accelerator opening sensor that detects the amount of depression of the accelerator pedal, an air flow meter that detects the intake air amount, a throttle opening sensor that detects the opening of the throttle valve, and a coolant temperature detection Sensor / switches such as a water temperature sensor that detects the engine speed, a vehicle speed sensor that detects the vehicle speed from the rotation of the vehicle drive shaft, and an ignition switch are connected to each cylinder of the engine 2. Engine control, such as an injector, an igniter that generates a high voltage for ignition, a fuel pump that pumps fuel from a fuel tank and supplies it to the injector, and a throttle drive motor that opens and closes a throttle valve provided in the intake pipe of the engine 2 Various actuators for are connected . The engine control unit 32 performs a predetermined engine control process for generating a driving torque necessary for driving the vehicle according to a control program stored in the ROM.

  The shift control unit 33 of the vehicle control ECU 31 includes an input shaft rotation speed sensor that detects the rotation speed of the input shaft of the continuously variable transmission 8, and an output shaft rotation that detects the rotation speed of the output shaft of the continuously variable transmission 8. Sensors such as a number sensor, a vehicle speed sensor that detects the vehicle speed from the rotation of the vehicle drive shaft, an oil temperature sensor that detects the temperature of the hydraulic oil, and a belt clamping pressure sensor that detects the hydraulic pressure (belt clamping pressure) in the secondary pulley are connected. In addition, a transmission solenoid for controlling the shift of the continuously variable transmission 8, a belt clamping solenoid for controlling the clamping pressure of the belt to suppress slippage of the belt of the continuously variable transmission 8, and a hydraulic pressure used for the shift control A line pressure control solenoid for controlling the line pressure that is the source pressure of the pressure, and a lockup pressure for operating a fastening force of a lockup clutch (to be described later) that fastens the input / output shaft of the torque converter 6 Solenoids, various actuators for the shift control such is connected. The shift control unit 33 performs a predetermined shift control process according to a control program stored in the ROM.

  Sensors such as a voltage sensor for detecting the charging voltage of the HV battery 24 are connected to the battery ECU 34. The battery ECU 34 outputs the current charge amount of the HV battery 24 to the HVECU 35 based on the detection signal of the sensor, or the voltage to be supplied to the inverter unit 27 to the HV battery 24 based on a command from the HVECU 35. Output a supply command.

  The HVECU 35 is communicably connected to another ECU via the communication line described above, acquires necessary information from the other ECU, outputs a control command for travel control to the other ECU, and The motor generator 4 is driven and controlled as necessary. The HVECU 35 is also connected to the inverter unit 27 via a predetermined signal line, and controls various inverters 26 and the like, and a drive current supplied from the HV battery 24 to the motor generator 4 or from the motor generator 4. The regenerative current regenerated to the HV battery 24 is adjusted. The HVECU 35 switches a plurality of modes, which will be described later, on the basis of a predetermined mode switching condition for vehicle travel control, outputs an operation command to the vehicle control ECU 31 corresponding to each mode, and controls the motor generator 4. .

  Next, the configuration of the continuously variable transmission and the hydraulic control operation described above will be described in detail. FIG. 2 is a block diagram showing the configuration of a hydraulic control system that controls the continuously variable transmission. FIG. 3 is an explanatory diagram showing a schematic configuration of the continuously variable transmission and its hydraulic control unit.

  As shown in FIG. 2, when the engine is driven, the hydraulic oil stored in the oil tank 17 is pumped up by the oil pump 5 driven by the engine 2 and supplied to the hydraulic circuit 14. On the other hand, when the engine is stopped, the vehicle control ECU 31 controls the drive of the electric motor 15. Then, hydraulic oil in the oil tank 17 is pumped up by the oil pump 16 driven by the electric motor 15 and supplied to the hydraulic circuit 14. The hydraulic circuit 14 generates a line pressure that is a source pressure for hydraulic control using the hydraulic oil supplied by at least one of the oil pumps 5 and 16, and executes the hydraulic control of the continuously variable transmission 8. Details of the switching control of both the oil pumps 5 and 16 will be described later.

  As shown in FIG. 3, the continuously variable transmission 8 includes a transmission mechanism including the primary pulley 11, the secondary pulley 12, and a V-belt 13, and a hydraulic circuit 14 that hydraulically controls the operation of the transmission mechanism. The hydraulic circuit 14 performs hydraulic control based on the control command output from the vehicle control ECU 31.

  The primary pulley 11 includes a fixed wheel 42 that is formed integrally with the input shaft 41 of the continuously variable transmission 8, and a movable wheel 43 that is disposed to face the fixed wheel 42. A tapered groove portion that sandwiches the V belt 13 is formed between the fixed wheel 42 and the movable wheel 43. On the opposite side of the movable wheel 43 from the V-belt 13, a case 45 is formed integrally with the input shaft 41 so as to form a primary oil chamber 44 having a variable volume with the movable wheel 43. Inside the input shaft 41, an oil passage 46 is formed for supplying and discharging hydraulic oil in the primary oil chamber 44 under the control of the hydraulic circuit 14. Then, by adjusting the amount of oil in the primary oil chamber 44, the movable wheel 43 is moved in the direction toward or away from the fixed wheel 42, and the engagement diameter of the V belt 13 is changed.

  The secondary pulley 12 includes a fixed wheel 52 that is formed integrally with the output shaft 51 of the continuously variable transmission 8, and a movable wheel 53 that is disposed to face the fixed wheel 52. A tapered groove portion that sandwiches the V-belt 13 is formed between the fixed wheel 52 and the movable wheel 53. A chamber wall 55 that forms a variable volume secondary oil chamber 54 with the movable wheel 53 is formed integrally with the output shaft 51 on the opposite side of the movable wheel 53 from the V belt 13. Inside the output shaft 51, an oil passage 56 is formed for supplying and discharging hydraulic oil in the secondary oil chamber 54 under the control of the hydraulic circuit 14. Then, by adjusting the amount of oil in the secondary oil chamber 54, the movable wheel 53 is moved in the direction toward or away from the fixed wheel 52, and the clamping pressure on the V belt 13 is maintained.

  In other words, the gear ratio between the input shaft and the output shaft is continuously changed by changing the engagement diameter of the V belt 13 in the primary pulley 11 and the secondary pulley 12 under the control of the hydraulic circuit 14. At this time, the V-belt 13 is prevented or suppressed from slipping with respect to each pulley by the clamping pressure of the secondary pulley 12.

  The hydraulic circuit 14 includes a line pressure control unit 60 that generates line pressure using hydraulic oil pumped from an oil tank by at least one of the oil pumps 5 and 16 and a primary pulley 11 that uses the line pressure. A primary oil amount control unit 70 that controls the oil amount in the oil chamber 44 and a secondary pressure control unit 80 that generates a secondary pressure that reduces the line pressure and supplies the secondary pressure to the secondary pulley 12 are provided.

  The line pressure control unit 60 includes a line pressure control valve 61 that operates to generate a line pressure, and a hydraulic control solenoid 62 that controls the operation thereof. The hydraulic control solenoid 62 drives the line pressure control valve 61 so that the line pressure becomes a magnitude corresponding to the current value supplied based on the command of the shift control unit 33.

  The primary oil amount control unit 70 controls the flow rate of the hydraulic oil flowing into and out of the primary oil chamber 44 of the primary pulley 11 using the line pressure generated by the line pressure control unit 60. The primary oil amount control unit 70 includes an upshift valve 71 that operates to increase the flow rate of the hydraulic oil, an upshift solenoid 72 that controls the operation thereof, and a downshift that operates to decrease the flow rate of the hydraulic oil. The valve 73 and the down-shifting solenoid 74 for controlling the operation thereof, and a decrease in pressure in the primary oil chamber 44 (referred to as “primary pressure”) are detected, and additional hydraulic oil is supplied to the oil chamber using the line pressure. The check valve 75 is provided.

  The up-shifting solenoid 72 and the down-shifting solenoid 74 operate by duty control in which energization is turned on / off based on a command from the shift control unit 33, respectively. The up-shifting solenoid 72 drives the up-shifting valve 71 so as to obtain an opening area corresponding to the duty ratio, and adjusts the supply amount of the hydraulic oil with the line pressure into the primary oil chamber 44. On the other hand, the downshift solenoid 74 drives the downshift valve 73 so as to obtain an opening area corresponding to the duty ratio of the current supplied based on the command of the shift control unit 33, and operates from the primary oil chamber 44. Adjust emissions to oil.

  The check valve 75 is disposed between the oil passage to which the line pressure is supplied and the down transmission valve 73. The check valve 75 is a check valve and can reduce the line pressure hydraulic oil and input it to the down speed change valve 73. However, the hydraulic oil flowing from the down speed change valve 73 is reduced in line pressure. Backflow to the supplied oil passage is prevented. That is, the check valve 75 senses the differential pressure between the line pressure and the primary pressure, and mechanically opens when the primary pressure decreases and the differential pressure becomes greater than a predetermined value, and the hydraulic oil at the line pressure is reduced. And input to the downshift valve 73. The hydraulic oil is supplied to the primary pulley 11 by opening the oil passage that connects the check valve 75 and the primary pulley 11 by the operation of the downshift solenoid 74. That is, the downshift solenoid 74 can reduce or increase the primary pressure by driving and controlling the position of the valve body of the downshift valve 73.

  The secondary pressure control unit 80 includes a secondary pressure control valve 81 that reduces the line pressure generated by the line pressure control unit 60. The operation of the secondary pressure control valve 81 is controlled by a hydraulic control solenoid 62. The hydraulic control solenoid 62 drives the secondary pressure control valve 81 so that the secondary pressure has a magnitude corresponding to the current value supplied based on the command of the shift control unit 33. That is, in the hydraulic circuit 14, the line pressure control valve 61 that generates the line pressure and the secondary pressure control valve 81 that generates the secondary pressure are controlled by the common hydraulic control solenoid 62. The size is proportional to.

Next, an outline of engine control and shift control will be described.
The engine control unit 32 of the vehicle control ECU 31 first performs an accelerator opening that represents an acceleration / deceleration request of the driver, an axle torque that is calculated based on a vehicle speed and a load that represents an actual traveling state of the vehicle, and predetermined traveling control. In order to achieve this, a target drive torque is calculated based on the requested axle torque input from another ECU.

  Then, the engine control unit 32 adds the vehicle speed detected by the vehicle speed sensor to the drive torque, that is, the axle rotation speed, and calculates the power necessary to extract the drive torque from the engine. Then, the engine torque and the engine speed for realizing this power are determined based on the condition that the fuel efficiency becomes the best. This condition is performed by referring to a control map (not shown) showing the relationship between the engine torque and the engine speed in association with the fuel efficiency and selecting an operating point along the optimum fuel efficiency line. The engine control unit 32 sets the engine torque calculated at this time as the target engine torque, and controls each actuator by feedback control that brings the current engine torque close to the target engine torque.

  On the other hand, the shift control unit 33 of the vehicle control ECU 31 calculates a target input shaft rotational speed that is a target rotational speed of the input shaft of the continuously variable transmission 8 based on the engine rotational speed corresponding to the target engine torque. The target gear ratio is calculated by dividing the input shaft speed by the output shaft speed. Then, feedback control using a deviation between the target speed ratio and the actual speed ratio which is the current speed ratio is performed, and a control instruction value to be output to each hydraulic actuator for speed control is calculated. In the hydraulic circuit 14, each hydraulic actuator is driven based on this control instruction value to control the operation of each valve, and the amount of hydraulic oil to be supplied to and discharged from the primary oil chamber 44 and the secondary oil so as to obtain the target gear ratio. The secondary pressure supplied to and discharged from the chamber 54 is adjusted.

Next, a vehicle travel control method in the vehicle control apparatus of the present embodiment will be described.
In this vehicle control device, four travel control modes are set, and the HVECU 35 selects one of the following 4WD mode, engine mode, EV mode and regeneration mode based on the travel state of the vehicle and the charged state of the HV battery 24 and the like. Select an appropriate cruise control mode.

  The 4WD mode is a travel mode in which both the engine 2 and the motor generator 4 are driven. The forward / reverse clutch 7 is engaged, and both the front wheels 1 and the rear wheels 3 are driven. This 4WD mode is selected when the vehicle is accelerating, or when the driving wheel is idle in the engine mode or EV mode.

  The engine mode is a travel mode in which the motor generator 4 is stopped and only the engine 2 is driven. The forward / reverse clutch 7 is engaged and only the front wheels 1 are driven. This engine mode is selected when the engine 2 is started or when the vehicle is in an operating region where engine efficiency is particularly high.

  The EV mode is a travel mode in which the engine 2 is stopped and only the motor generator 4 is driven, the forward / reverse clutch 7 is released, and only the rear wheel 3 is driven. This EV mode is selected when the vehicle is in a driving region where the engine efficiency is poor, such as when the vehicle starts at a relatively low load, or when traveling at a low speed or down a gentle slope.

  The regeneration mode is a travel mode in which the motor generator 4 is regenerated to charge the HV battery 24, and the engine 2 is stopped and the forward / reverse clutch 7 is released, and only the rear wheel 3 is driven. This regeneration mode is selected when the charge amount of the HV battery 24 is low.

  Next, the oil pump switching process in the shift control of the present embodiment will be described in detail. FIG. 4 is a timing chart showing the control state of the oil pump in the shift control. The horizontal axis of the figure represents the passage of time, and the vertical axis represents the oil pressure of the oil pump 5 (first oil pump), the oil pressure of the oil pump 16 (second oil pump), and the combined oil pressure from the top. . In the figure, the solid line represents the output instruction value, and the broken line represents the actual output value.

  In the present embodiment, in order to generate the line pressure by the hydraulic circuit 14 in the above-described shift control, a process for ensuring the hydraulic pressure to be supplied to the hydraulic circuit 14 when each oil pump is switched is performed.

  For example, in the 4WD mode and the engine mode in which the engine 2 is driven, the oil pump 5 is driven and hydraulic control for shift control is performed. In the EV mode in which the engine 2 is stopped, the oil pump 16 is Driven to perform hydraulic control. For this reason, in order to prevent the supply hydraulic pressure to the hydraulic circuit 14 from being insufficient at the time of switching between the two oil pumps, an overlap period in which both the oil pumps are driven simultaneously is provided.

  That is, when the transition condition from the 4WD mode or the engine mode to the EV mode is satisfied, the vehicle control ECU 31 outputs a drive command for the electric motor 15 at, for example, time t1, and drives the oil pump 16 before stopping the oil pump 5. To start. At this time, the output instruction value to the oil pump 16 is set equal to the oil pressure (APa) of the oil pump 5, and the oil pressure of the oil pump 16 gradually increases.

  Then, a stop command for the engine 2 is output at a time t2 when a predetermined delay time Δt (corresponding to a “predetermined period”) has elapsed from the drive command to the oil pump 16. As a result, the fuel cut and the ignition cut are executed, the engine 2 is stopped, the drive of the oil pump 5 is also stopped, and the hydraulic pressure gradually decreases.

  Thus, when switching from the oil pump 5 to the oil pump 16, the oil pressure is increased to some extent after driving the oil pump 16 in advance, and then the driving of the oil pump 5 is stopped. Prevents the decline of In this control, when there is a control instruction from the HVECU 35 so that the oil pump is switched at time t2, the second oil pump is driven in advance, and then the first oil pump is stopped after a predetermined period Δt has elapsed. If the control instruction is given to switch the oil pump at time t1, the second oil pump is driven for the time being, and then the first oil pump is turned on after a predetermined period Δt has elapsed. You may control to stop. As shown in the figure, the actual output value by the combined oil pressure exceeds the output command value (target oil pressure) immediately after switching, but the oil pressure generated at this time is regulated by the hydraulic circuit 14, so there is no problem. Absent.

  Next, the flow of the vehicle control process of this embodiment will be briefly described. Note that the vehicle control process is characterized by an oil pump switching process associated with a change in the travel mode, and therefore this switching process will be mainly described. Here, an example will be described in which the traveling mode of the vehicle is changed from the state in which the oil pump 5 is driven by the engine drive, and the oil pump 16 is switched to be driven by the motor drive. FIG. 5 is a flowchart showing a flow of processing executed by the vehicle control ECU. Hereinafter, the flow of this process will be described using step numbers (hereinafter referred to as “S”).

  As described above, the vehicle control ECU 31 determines whether or not a condition for shifting from the 4WD mode or the engine mode to the EV mode is satisfied and a traveling mode switching command is output (S1). At this time, if it is determined that the switching command is not output (S1: NO), the process is terminated as it is.

  On the other hand, if it is determined in S1 that a switching command has been output (S1: YES), first, the electric motor 15 is driven to operate the oil pump 16, and supply of hydraulic pressure is started (S2). Then, an elapse of a delay time set in advance assuming that there is no drop in hydraulic pressure at the time of switching is waited (S3).

  When the delay time has elapsed (S3: YES), the engine 2 is stopped to stop driving the oil pump 5, and the motor generator 4 is driven (S4). Thereby, the oil pump for shift control is switched.

In the present embodiment, the vehicle control ECU 31 corresponds to hydraulic control means, shift control means, and pump drive control means.
As described above, in the present embodiment, when the engine-driven oil pump 5 is switched to the motor-driven oil pump 16, the oil pump 16 is driven before the oil pump 5 is stopped, and the hydraulic pressure is reduced. Is increased. For this reason, the combined hydraulic pressure of both oil pumps can be prevented from dropping immediately after the switching, and the necessary original pressure can be maintained. For this reason, optimal hydraulic pressure control can be realized when the oil pump is switched. As a result, stable shift control, and thus vehicle control, can be realized even when the oil pump is switched.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. The present embodiment is the same as the first embodiment except that the processing part at the time of switching the oil pump is different. For this reason, the description of the same parts as those in the first embodiment is omitted. FIG. 6 is a timing chart showing the control state of the oil pump in the shift control of the second embodiment, and corresponds to FIG.

  As shown in the figure, in order to prevent the supply hydraulic pressure to the hydraulic circuit 14 from being insufficient when switching from the oil pump 5 to the oil pump 16, the target hydraulic pressure immediately after switching by the oil pump 16 is changed after switching. It is set higher than the normal hydraulic pressure.

  That is, when the transition condition from the 4WD mode or the engine mode to the EV mode is satisfied, the vehicle control ECU 31 outputs a stop command for the engine 2 and a drive command for the electric motor 15 at, for example, time t21. For this reason, the drive of the oil pump 5 is stopped and the oil pump 16 is driven. At this time, the delay time Δt2 (corresponding to the “predetermined period”) immediately after the switching of the oil pump 16 is set higher by ΔP than the output instruction value (APa) at the steady state after the switching. The oil pressure of the oil pump 16 rises quickly. The output instruction value of the oil pump 16 is changed to a steady output instruction value (APa) at time t22 when the delay time Δt2 has elapsed. By such control, there is no drop in the combined hydraulic pressure after switching, and a sufficient hydraulic pressure can be secured.

  Next, the flow of the vehicle control process of this embodiment will be briefly described. FIG. 7 is a flowchart showing the flow of processing executed by the vehicle control ECU, and corresponds to FIG. Hereinafter, the flow of this process will be described using step numbers (hereinafter referred to as “S”).

  As described above, the vehicle control ECU 31 determines whether or not a condition for shifting from the 4WD mode or the engine mode to the EV mode is satisfied and a traveling mode switching command is output (S21). At this time, if it is determined that the switching command is not output (S21: NO), the process is terminated as it is.

  On the other hand, if it is determined in S21 that the switching command has been output (S21: YES), the output instruction value (target hydraulic pressure) of the oil pump 16 is set to be higher by a predetermined amount than the output instruction value (APa) in the steady state (S22). . Then, the engine 2 is stopped to stop driving the oil pump 5, and the electric motor 15 is driven to start driving the oil pump 16 (S23). Then, an elapse of a delay time set in advance assuming that there is no drop in hydraulic pressure at the time of switching is waited (S24).

  Then, when the delay time has elapsed (S24: YES), the output instruction value of the oil pump 16 is changed to a normal output instruction value (S25). Thereby, the oil pump for shift control is switched.

In the present embodiment, the vehicle control ECU 31 corresponds to hydraulic control means, shift control means, and pump drive control means.
As described above, in the present embodiment, when switching from the engine-driven oil pump 5 to the motor-driven oil pump 16, the target hydraulic pressure immediately after switching by the oil pump 16 is the hydraulic pressure required after switching. Higher than. For this reason, the combined hydraulic pressure of both oil pumps can be prevented from dropping immediately after the switching, and the necessary original pressure can be maintained. For this reason, it is possible to realize optimal hydraulic pressure control when the oil pump is switched. As a result, stable shift control, and thus vehicle control, can be realized even when the oil pump is switched.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the specific embodiment, and it can be changed and modified within the spirit of the present invention. Not too long.

  For example, the control amount of each oil pump may be corrected by paying attention to the fact that the viscosity of the hydraulic oil supplied by each oil pump changes depending on the oil temperature. That is, when the oil temperature is lowered and the viscosity is increased, the oil pressure tends to be difficult to increase. Therefore, a correction that increases the control amount can be considered.

  8 and 9 are timing charts showing modifications to the first embodiment and correspond to FIG. In these drawings, a solid line represents an output instruction value at a high temperature, an alternate long and short dash line represents an output instruction value at a low temperature, and a broken line represents an actual output value.

  That is, as shown in FIG. 8, by setting the delay time from when the oil pump 16 is activated in advance to when the oil pump 5 is stopped to be longer as the hydraulic oil temperature is lower, the required hydraulic pressure is May be secured.

Alternatively, as shown in FIG. 9, the required hydraulic pressure may be ensured by setting the target hydraulic pressure for the delay time to be higher as the hydraulic oil temperature is lower.
FIG. 10 and FIG. 11 are timing charts showing modifications to the second embodiment, and correspond to FIG. In these drawings, a solid line represents an output instruction value at a high temperature, an alternate long and short dash line represents an output instruction value at a low temperature, and a broken line represents an actual output value.

  That is, as shown in FIG. 10, the required oil pressure may be ensured by setting the holding period of the target oil pressure immediately after the switching so that it becomes longer as the oil temperature of the hydraulic oil is lower.

Or as shown in FIG. 11, you may make it ensure a required hydraulic pressure by setting the target hydraulic pressure immediately after switching so that it may become so high that the oil temperature of hydraulic fluid is low.
In each of the above-described embodiments and modifications, an example in which the hydraulic control device of the present invention is applied to shift control of a continuously variable transmission has been described, but it is also possible to apply it to shift control of a multi-stage automatic transmission. It is. Further, as long as it is a control target whose hydraulic source can be switched by stopping and restarting the engine, it can be applied to various control targets such as a clutch and a brake by hydraulic control.

  In each of the above-described embodiments and modifications, an example in which the present invention is applied when the driving mode is switched in a hybrid vehicle has been described. However, the present invention automatically stops the vehicle, for example, when waiting for a signal or in a traffic jam. -It can also be applied when performing idle stop control for restarting.

  In each of the above embodiments and modifications, an example is described in which the shift control device of the present invention is applied when shifting from the 4WD mode or the engine mode to the EV mode, that is, when switching from the mechanical oil pump to the electric oil pump. However, conversely, the present invention can also be applied to a case where the electric oil pump is switched to the mechanical oil pump, for example, when the EV mode is changed to the engine mode.

It is a system configuration figure showing the composition of the vehicle control device concerning a 1st embodiment. It is a block diagram showing the structure of the hydraulic control system which controls a continuously variable transmission. It is explanatory drawing showing schematic structure of a continuously variable transmission and its hydraulic control part. It is a timing chart showing the control state of the oil pump in shift control. It is a flowchart showing the flow of the process which vehicle control ECU performs. It is a timing chart showing the control state of the oil pump in the shift control of the second embodiment. It is a flowchart showing the flow of the process which vehicle control ECU performs. It is a timing chart showing the modification with respect to 1st Embodiment. It is a timing chart showing the modification with respect to 1st Embodiment. It is a timing chart showing the modification with respect to 2nd Embodiment. It is a timing chart showing the modification with respect to 2nd Embodiment. It is a timing chart showing the control state of the oil pump by the conventional hydraulic control apparatus.

Explanation of symbols

2 Engine 4 Motor generator 5, 16 Oil pump 8 Continuously variable transmission 11 Primary pulley 12 Secondary pulley 13 Belt 14 Hydraulic circuit 15 Electric motor 17 Oil tank 21 Motor generator 31 Vehicle control ECU
32 Engine control unit 33 Shift control unit 60 Line pressure control unit 70 Primary oil amount control unit 80 Secondary pressure control unit

Claims (12)

A hydraulic control device that controls a hydraulic drive unit that is hydraulically driven,
The hydraulic pressure supplied to the hydraulic drive unit is controlled using at least one of hydraulic oil supplied from a first oil pump driven by an engine and hydraulic oil supplied from a second oil pump driven by an electric motor. Hydraulic control means;
When controlling the drive of the first oil pump and the second oil pump and switching the drive from one oil pump to the other oil pump, the other oil pump is driven and the one oil pump is driven after a predetermined period of time. A pump drive control means for stopping the drive of the pump;
A hydraulic control device comprising:   The hydraulic control apparatus according to claim 1, wherein the pump drive control unit sets the predetermined period to be longer as the oil temperature of the hydraulic oil is lower.   2. The hydraulic control apparatus according to claim 1, wherein the pump drive control means sets the target hydraulic pressure for the predetermined period to be higher as the oil temperature of the hydraulic oil is lower. A hydraulic control device that controls a hydraulic drive unit that is hydraulically driven,
The hydraulic pressure supplied to the hydraulic drive unit is controlled using at least one of hydraulic oil supplied from a first oil pump driven by an engine and hydraulic oil supplied from a second oil pump driven by an electric motor. Hydraulic control means;
When the drive control of the first oil pump and the second oil pump is performed and the drive is switched from one oil pump to the other oil pump, the target oil pressure immediately after the switching by the other oil pump is set to a fixed value after the switching. A pump drive control means for setting higher than the normal hydraulic pressure,
A hydraulic control device comprising:   5. The hydraulic control apparatus according to claim 4, wherein the pump drive control means sets the holding period of the target hydraulic pressure immediately after the switching so as to become longer as the oil temperature of the hydraulic oil is lower.   6. The hydraulic control apparatus according to claim 5, wherein the pump drive control means sets the target hydraulic pressure so that the target hydraulic pressure increases as the oil temperature of the hydraulic oil decreases. A shift control device for controlling a transmission having a hydraulic drive unit that is hydraulically driven,
An original pressure is generated using at least one of hydraulic oil supplied from a first oil pump driven by an engine and hydraulic oil supplied from a second oil pump driven by an electric motor, and the original pressure is used. Shift control means for controlling the gear ratio of the transmission and / or the engagement of the clutch by supplying the controlled hydraulic pressure to the hydraulic drive unit;
When controlling the drive of the first oil pump and the second oil pump and switching the drive from one oil pump to the other oil pump, the other oil pump is driven and the one oil pump is driven after a predetermined period of time. A pump drive control means for stopping the drive of the pump;
A shift control apparatus comprising: A shift control device for controlling a transmission having a hydraulic drive unit that is hydraulically driven,
An original pressure is generated using at least one of hydraulic oil supplied from a first oil pump driven by an engine and hydraulic oil supplied from a second oil pump driven by an electric motor, and the original pressure is used. Shift control means for controlling the gear ratio of the transmission and / or the engagement of the clutch by supplying the controlled hydraulic pressure to the hydraulic drive unit;
When the drive control of the first oil pump and the second oil pump is performed and the drive is switched from one oil pump to the other oil pump, the target oil pressure immediately after the switching by the other oil pump is set to a fixed value after the switching. A pump drive control means for setting higher than the normal hydraulic pressure,
A shift control apparatus comprising: A transmission having a hydraulic drive unit that is hydraulically driven;
A first oil pump driven by an engine to supply hydraulic oil toward the hydraulic drive unit;
A second oil pump that is driven by an electric motor and supplies hydraulic oil toward the hydraulic drive unit;
Hydraulic control means for controlling the hydraulic pressure supplied to the hydraulic drive unit using the hydraulic oil supplied from at least one of the first oil pump and the second oil pump;
When controlling the drive of the first oil pump and the second oil pump and switching the drive from one oil pump to the other oil pump, the other oil pump is driven and the one oil pump is driven after a predetermined period of time. A pump drive control means for stopping the drive of the pump;
A vehicle control device comprising: Applied to a hybrid vehicle having the engine and motor generator as a drive source,
The pump drive control means drives the second oil pump in advance when switching from a travel mode using at least the engine as a drive source to a travel mode using the motor generator as a drive source after stopping the engine, The vehicle control device according to claim 9, wherein the driving of the first oil pump is stopped by stopping the engine after the lapse of the predetermined period. A transmission having a hydraulic drive unit that is hydraulically driven;
A first oil pump driven by an engine to supply hydraulic oil toward the hydraulic drive unit;
A second oil pump that is driven by an electric motor and supplies hydraulic oil toward the hydraulic drive unit;
Hydraulic control means for controlling the hydraulic pressure supplied to the hydraulic drive unit using the hydraulic oil supplied from at least one of the first oil pump and the second oil pump;
When the drive control of the first oil pump and the second oil pump is performed and the drive is switched from one oil pump to the other oil pump, the target oil pressure immediately after the switching by the other oil pump is set to a fixed value after the switching. A pump drive control means for setting higher than the normal hydraulic pressure,
A vehicle control device comprising: Applied to a hybrid vehicle having the engine and motor generator as a drive source,
The pump drive control means stops the engine when switching from a travel mode using at least the engine as a drive source to a travel mode using the motor generator as a drive source by stopping the engine. 12. The vehicle control device according to claim 11, wherein the operation of the oil pump is stopped and the electric motor is driven to operate the second oil pump based on the target hydraulic pressure.

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