JP5445309B2 - Hydraulic control device for vehicle - Google Patents

Description

  The present invention relates to a hydraulic control apparatus for a vehicle configured to drive an oil pump with power from a power source and to accumulate hydraulic pressure discharged from the oil pump in an accumulator.

  There is known a vehicle hydraulic control device that can supply oil discharged from an oil pump to a hydraulic chamber and store it in an accumulator through a path for supplying oil discharged from the oil pump to the hydraulic chamber. One example thereof is described in Patent Document 1. The vehicle hydraulic control device described in Patent Document 1 supplies oil to a transmission control circuit and a lubrication circuit, and the hydraulic control device is provided with an oil pump driven by an electric motor. The oil pump discharge oil passage is connected to the import of the mode select valve. This mode select valve has two out ports. One out port is connected to a lubrication circuit, and the other out port is connected to a pressure accumulating circuit via a check valve. The switching of the mode select valve, that is, the switching for connecting the import to one of the two out-ports is made by the solenoid signal pressure.

  Further, an accumulator is connected to the pressure accumulating circuit, and a hydraulic pressure sensor that detects a pressure accumulating state of the accumulator is provided. A line pressure circuit is connected to the pressure accumulation circuit via a primary modulator valve, and the line pressure circuit is connected to a hydraulic servo via a control valve for shift control. This hydraulic servo controls the engagement and disengagement of each clutch that controls the transmission gear ratio. In the hydraulic control device described in Patent Document 1, it is determined whether the current mode is the lubrication mode or the pressure accumulation mode, and the mode select valve is switched based on the determination result to accumulate the oil discharged from the oil pump. Control is applied to the circuit or lubrication circuit.

  In the invention described in Patent Document 1, when it is determined that the current mode is the pressure accumulation mode, the oil pump is driven by the electric motor, and the mode select valve is switched and discharged from the oil pump. Oil is supplied to the accumulator circuit. In this way, when oil is supplied to the pressure accumulation circuit, pressure is accumulated in the accumulator until the set maximum pressure accumulation time elapses.

  An example of a hydraulic control device in which an accumulator is provided in an oil passage for supplying oil discharged from an oil pump to a clutch of an automatic transmission is described in Patent Document 2, and an example of a hydraulic control device of a continuously variable transmission is disclosed in Patent Document 2. Patent Document 4 describes an example of a hydraulic control device described in Document 3 in which an accumulator is provided in an oil passage that supplies oil discharged from an oil pump to a hydraulic chamber of a continuously variable transmission.

JP 2004-84928 A JP 2002-130449 A JP 2007-224974 A JP-A-3-134368

  However, in the vehicle hydraulic control device described in Patent Document 1 described above, since the accumulator is constantly accumulated until the maximum pressure is reached, the power of the electric motor may be excessively consumed by driving the oil pump. There was room for improvement in that respect.

  This invention was made paying attention to said technical subject, and it aims at providing the hydraulic control apparatus for vehicles which can suppress that the motive power of the power source which drives an oil pump is consumed unnecessarily. To do.

In order to achieve the above object, a first aspect of the present invention is a power transmission device provided in a path from a power source of a vehicle to a drive wheel, and oil is supplied to control a power transmission state of the power transmission device. An oil pump that is driven by the power of the power source and discharges oil supplied to the hydraulic chamber, and is provided in an oil supply path from the oil pump to the hydraulic chamber. in the hydraulic control apparatus for a vehicle having an accumulator for accumulating hydraulic pressure of the discharged oil from the driver at the time of starting of the vehicle speed or the vehicle, property or the vehicle is one of a road slope location is located, based on at least one condition, e Bei pressure accumulation control means for changing the reference pressure to start accumulating in the accumulator, the hydraulic pressure to the reference oil in the supply oil passage For more, it is characterized in that it is configured to perform accumulator to the accumulator.

The invention of claim 2 comprises, in addition to the configuration of claim 1, a judging means for judging whether the vehicle is running by the power of the power source or whether the vehicle is stopped, and the pressure accumulation control means comprises: when the vehicle is determined to be traveling by the power of the power source, and means for changing said reference hydraulic pressure based on the vehicle speed, when the vehicle is determined to have stopped, before Symbol The vehicle hydraulic control apparatus includes means for changing the reference hydraulic pressure based on characteristics of a driver at the time of starting of the vehicle or a road gradient of a place where the vehicle is located.

  According to a third aspect of the invention, in addition to the configuration of the first or second aspect, the pressure accumulating control means is a means for making the reference hydraulic pressure relatively higher as the vehicle speed is relatively higher, or for a characteristic that prefers a sudden start. The vehicle hydraulic control device includes means for relatively increasing the reference hydraulic pressure as the driver of the vehicle, or means for relatively increasing the reference hydraulic pressure as the road gradient is relatively large. It is.

  According to the first aspect of the present invention, when the oil pump is driven by the power of the power source and the hydraulic pressure of the oil discharged from the oil pump is stored in the accumulator, the reference hydraulic pressure that determines whether or not the accumulator stores the pressure. Is determined based on at least one condition of the vehicle speed, the characteristics of the driver at the start of the vehicle, or the slope of the road on which the vehicle is stopped. Therefore, it is possible to suppress unnecessary power consumption of the power source that drives the oil pump.

According to the invention of claim 2, in addition to achieving the same effects as the invention of claim 1, when the vehicle is running by the power of the power source, the reference hydraulic pressure determined based on the vehicle speed Merare, If the vehicle is stopped, the reference pressure is determined Me on the basis of the driver's characteristics or road gradient, during starting of the vehicles. Therefore, the power consumption of the power source that drives the oil pump can be changed in accordance with the required condition of oil in the hydraulic chamber.

  According to the invention of claim 3, in addition to obtaining the same effect as that of the invention of claim 1 or 2, the higher the vehicle speed, the relatively higher the reference hydraulic pressure or the sudden start. It is possible to make the reference oil pressure relatively higher as the driver has a preferred characteristic, or to make the reference oil pressure relatively higher as the road gradient is relatively larger.

It is a flowchart which shows the example of control performed with the hydraulic control apparatus for vehicles of this invention. 1 is a schematic diagram showing a configuration of a vehicle having a vehicle hydraulic control device of the present invention. It is an example of the map used with the flowchart of FIG.

  The oil pump in the present invention includes a vane pump, a gear pump, a piston pump, and the like. The power source in the present invention includes an engine that generates power by burning fuel, and an electric motor that converts electrical energy into kinetic energy. The power transmission device according to the present invention includes a transmission capable of changing a gear ratio between an input rotation speed and an output rotation speed, a clutch for controlling torque between the input member and the output member, and the like. Here, the transmission may be either a continuously variable transmission or a stepped transmission. The power transmission state in the present invention includes a gear ratio and a torque capacity. The supply path in the present invention includes an oil path through which oil passes, a port formed in a valve body in which the oil path is formed, a valve provided in the oil path, and the like.

  Next, specific examples of the present invention will be described with reference to the drawings. FIG. 2 schematically shows an example in which the present invention is applied to a hydraulic control device 32 intended for a power transmission device including a continuously variable transmission 1 mounted on a vehicle. The continuously variable transmission 1 is a conventionally known belt type, and a belt 35 is wound around a driving pulley 2 and a driven pulley 3 to transmit torque between these pulleys 2 and 3, and By changing the wrapping radius of the belt 35 around the pulleys 2 and 3, the gear ratio between the input rotation speed and the output rotation speed can be changed steplessly (continuously). Yes. More specifically, each of the pulleys 2 and 3 includes a fixed piece and a movable piece arranged so as to approach and separate from the fixed piece, and V between the fixed piece and the movable piece. A groove-like belt winding groove is formed.

  The pulleys 2 and 3 are provided with hydraulic actuators 4 and 5 for moving the movable pieces in the direction along the rotation center axis. Any one of these hydraulic actuators 4, 5, for example, the hydraulic chamber 5 A of the hydraulic actuator 5 in the driven pulley 3 is supplied with a hydraulic pressure that generates a clamping pressure with which the driven pulley 3 clamps the belt 35. The other of the hydraulic actuators 4 and 5, for example, the hydraulic chamber 4 </ b> A of the hydraulic actuator 4 in the drive pulley 2 is configured to be supplied with pressure oil for changing speed by changing the winding radius of the belt 35. ing.

  A C1 clutch 6 for transmitting and interrupting drive torque is provided on the input side or output side of the continuously variable transmission 1. The C1 clutch 6 is a clutch whose torque capacity is controlled according to the supplied hydraulic pressure, and is constituted by, for example, a wet multi-plate clutch. Further, a forward / reverse switching device (not shown) is provided on the path from the engine 10 to the drive wheel 36. This forward / reverse switching device is composed of, for example, a planetary gear mechanism and a friction engagement device, and is a device that switches the rotation direction of the rotating element forward and backward by switching engagement and release of the friction engagement device. is there. A hydraulic chamber (not shown) for controlling the engagement and release of the friction engagement device is provided, and the oil in the oil passage 15 is supplied to the hydraulic chamber.

  The continuously variable transmission 1 and the C1 clutch 6 and the forward / reverse switching device transmit torque for traveling the vehicle and are set to a transmission torque capacity corresponding to the hydraulic pressure. High hydraulic pressure corresponding to the torque is supplied to the hydraulic chambers of the hydraulic actuators 4 and 5 and the C1 clutch 6 and the hydraulic chambers for controlling the engagement and release of the friction engagement device of the forward / reverse switching device. Therefore, the hydraulic chambers 4A, 5A, the hydraulic chamber (not shown) of the C1 clutch 6, and the hydraulic chamber that controls the engagement and release of the friction engagement device of the forward / reverse switching device are the high hydraulic pressure supply unit.

  On the other hand, the power transmission device including the continuously variable transmission 1 is provided with a torque converter (T / C) 7 having a lock-up clutch (not shown). The configuration of the torque converter 7 is the same as that conventionally known, and torque amplification occurs in the converter region where the rotational speed difference between the pump impeller and the turbine runner is large (the speed ratio is smaller than a predetermined value). Further, the coupling range in which the rotational speed difference is small (the speed ratio is greater than a predetermined value) is configured to function as a fluid coupling having no torque amplification action. The lockup clutch is configured to directly connect a front cover integrated with a pump impeller as an input side member and a hub integrated with a turbine runner via a friction plate. A control valve (L / U control valve) 8 is provided for controlling the lock-up hydraulic pressure for bringing the friction plate into contact with the front cover and separating the friction plate. The control valve 8 is for controlling the direction and pressure of the hydraulic pressure supplied to the lock-up clutch, and therefore the control valve 8 operates at a relatively low hydraulic pressure.

  As described above, in the power transmission device from the engine 10 to the driving wheel 36, sliding, heat generation, and wear are generated during power transmission, such as a frictional contact with each other, a bearing, and a gear meshing portion. A portion to be lubricated 9 exists, and oil is supplied to the portion to be lubricated 9 to be cooled and lubricated. Since the lubricated portion 9 only needs to be supplied with a required amount of oil (lubricating oil) even at a low pressure, the lubricated portion 9, the control valve 8 or the torque converter 7 is referred to as a low hydraulic pressure supply portion.

  Next, a configuration for supplying and discharging hydraulic pressure to and from the high hydraulic pressure supply unit and the low hydraulic pressure supply unit will be described. The example shown in FIG. 2 is an example in which an oil pump (mechanical oil pump) 11 driven by an engine 10 mounted on a vehicle is used as a hydraulic pressure source. The engine 10 is a heat engine that outputs power by burning fuel such as a gasoline engine. Further, a clutch (not shown) for connecting or disconnecting the power transmission path between the engine 10 and the oil pump 11 is provided. An electric motor may be provided as a power source for transmitting torque to the drive wheels 36 instead of the engine 10 or in addition to the engine 10. The continuously variable transmission 1, the C1 clutch 6, the torque converter 7 and the like are arranged on a power transmission path from the engine 10 to the drive wheels 36.

  The oil pump 11 is configured to suck oil from the oil pan 33 and discharge oil to the oil passage 34. A pressure regulating valve 12 that regulates the oil pressure of the oil passage 34 to a predetermined pressure is provided. The pressure regulating valve 12 includes a spool that reciprocates in a predetermined direction, a port 12A that connects the oil passage 34 and the lubricated portion 9, a port 12B that connects the oil passage 34 and the oil pan 33, and the spool in one direction. And a feedback port that presses the spool in a direction opposite to the spring, and an electromagnetic coil that generates a magnetic attractive force that presses the spool in the same direction as the spring. doing. In the pressure regulating valve 12, when the oil pressure in the oil passage 34 is relatively low, the spool is pressed by the force of the spring and the ports 12A and 12B are closed. It is not discharged to the pan 33.

  When the oil pressure in the oil passage 34 rises, the spool moves against the spring force by the oil pressure in the feedback port, the port 12A opens, and the oil in the oil passage 34 is discharged to the lubricated portion 9. When the oil pressure in the oil passage 34 further increases, the spool further moves, the ports 12A and 12B are both opened, the oil in the oil passage 34 is discharged to the lubricated portion 9 and the oil pan 33, and the oil pressure in the oil passage 34 is increased. Be controlled. Further, in the pressure regulating valve 12, by controlling the current value supplied to the electromagnetic coil, it is possible to adjust the hydraulic pressure of the oil passage 34 where the spool moves against the force of the spring and the magnetic attractive force. it can. Specifically, as the magnetic attractive force formed by energization of the electromagnetic coil is relatively increased, the oil in the oil passage 34 is supplied to the lubricated portion 9 and the oil until the oil pressure in the oil passage 34 is relatively increased. It is not discharged to the pan 33. In this way, the oil pressure of the oil passage 34 is controlled, and the oil pressure is supplied to the torque converter 7 via the control valve 8.

  On the other hand, the oil passage 34 is communicated with the accumulator (pressure accumulator) 14 through the check valve 13 and the oil passage 15. The check valve 13 is a one-way valve that opens when pressure oil flows from the oil pump 11 toward the accumulator 14 and closes to prevent the flow of pressure oil in the opposite direction. The accumulator 14 is a container in which a piston, an elastic expansion body, and the like pressed by an elastic body are accommodated in a container. That is, as the accumulator 14, any of a piston type, a bladder type, a diaphragm type, or the like may be used. Further, a solenoid valve 39 capable of opening and closing a port connecting the oil passage 15 and the accumulator 14 accumulator 14 is provided. By switching between energization and non-energization of the solenoid valve 39, the pressure accumulation chamber of the accumulator 14 and the oil passage 15 are connected or disconnected. Therefore, if the pressure accumulator chamber of the accumulator 14 and the oil passage 15 are connected, the hydraulic pressure stored in the accumulator 14 is supplied to the actuator 4 in the drive pulley 2, the actuator 5 in the driven pulley 3, and the C1 clutch 6. can do.

  Further, in the hydraulic control device 32 shown in FIG. 2, an electric oil pump 28 is provided in addition to the oil pump 11 driven by the engine 10. An electric motor 29 for driving the electric oil pump 28 is provided. In addition, a generator 31 that is driven by the engine 1 to generate electric power is provided, and the generator 31 is connected to an electric motor 29. The generator 31 may be either a DC generator or an AC generator. Therefore, the generator 31 can generate power with the power of the engine 10 and the electric motor 29 can be driven with the electric power. A discharge valve of the electric oil pump 28 is connected to the oil passage 15 with a check valve 38 interposed. The check valve 38 is a one-way valve that opens when pressure oil flows from the electric oil pump 28 toward the oil passage 15 and closes to prevent the flow of pressure oil in the opposite direction. In the hydraulic control device 32 configured as described above, the hydraulic pressure of the oil discharged from the oil pump 11 and the hydraulic pressure of the oil discharged from the electric oil pump 28 can be stored in the accumulator 14.

  An oil passage 16 is connected to the hydraulic chamber 4 </ b> A of the actuator 4, and a supply-side electromagnetic on-off valve DSP <b> 1 that connects and disconnects the oil passage 15 and the oil passage 16 is provided. The supply-side electromagnetic on-off valve DSP1 is electrically controlled to open and close the oil supply path, thereby supplying pressure oil to the actuator 4 and blocking the supply of pressure oil. An oil passage 18 is connected to the hydraulic chamber 5 </ b> A of the actuator 5, and a supply-side electromagnetic on-off valve DSS <b> 1 that connects and shuts off the oil passage 15 and the oil passage 18 is provided. The supply-side electromagnetic on-off valve DSS1 is electrically controlled to open and close the path for supplying the oil in the oil path 15 to the actuator 5, thereby supplying pressure oil to the actuator 5 and supplying the pressure oil. It is configured to block. Further, an oil passage 19 is connected to the hydraulic chamber that controls engagement and release of the C1 clutch 6, and a supply-side electromagnetic on-off valve DSC 1 that connects and disconnects the oil passage 15 and the oil passage 19 is provided. . The supply-side electromagnetic on-off valve DSC1 is electrically controlled to open and close the oil supply path, thereby supplying pressure oil to the C1 clutch 6 and blocking the supply of pressure oil. .

  An oil passage 17 is provided for communicating the hydraulic chambers of the actuators 4 and 5 and the hydraulic chamber of the C1 clutch 6 to the oil pan 33. The discharge-side electromagnetic for connecting and disconnecting the oil passage 17 and the oil passage 16 is provided. An on-off valve DSP2 is provided. By electrically controlling the discharge-side electromagnetic on-off valve DSP2 to open and close the path for discharging the oil of the actuator 4 to the oil pan 33, the pressure oil is discharged from the hydraulic chamber 4A of the actuator 4 to the oil pan 33, Moreover, it is comprised so that discharge | emission of pressure oil can be interrupted | blocked. Similarly, a discharge-side electromagnetic on-off valve DSS2 that connects and shuts off the oil passage 18 and the oil passage 17 is provided. By electrically controlling the discharge side electromagnetic opening / closing valve DSS2 and opening / closing a path for discharging oil from the hydraulic chamber 5A of the actuator 5 to the oil pan 33, the hydraulic oil is discharged from the actuator 5 to the oil pan 33, Moreover, it is comprised so that discharge | emission of pressure oil may be interrupted | blocked.

  Further, a discharge side electromagnetic on-off valve DSC2 for connecting and blocking the oil passage 19 and the oil passage 17 is provided. By electrically controlling the discharge-side electromagnetic on-off valve DSC2 to open and close the path for discharging the oil in the hydraulic chamber of the C1 clutch 6 to the oil pan 33, the pressure oil is discharged from the C1 clutch 6 to the oil pan 33. In addition, it is configured so that the discharge of pressure oil can be shut off. As these electromagnetic open / close valves DSP1, DSS1, DSC1, DSP2, DSS2, DSC2, valves configured so as not to leak hydraulic pressure even in the closed state, such as poppet valves and check valves, are used. Can do. In FIG. 2, the hydraulic pressure stored in the accumulator 14 is supplied to the actuators 4 and 5 and the C1 clutch 6 by controlling the solenoid valve 39, but this solenoid valve 39 is not used. In addition, the hydraulic pressure supplied to the actuators 4 and 5 and the C1 clutch 6 can be controlled by controlling the operations of the various electromagnetic on-off valves DSP1, DSS1, DSC1, DSP2, DSS2, DSC2.

  On the other hand, an electronic control unit 37 for controlling the engine 10, the continuously variable transmission 1, and the hydraulic control unit 32 is provided. The electronic control unit 37 includes a vehicle speed, an operating state of an accelerator pedal, an engine speed, a brake pedal. A sensor for detecting an operation state, an internal pressure of the accumulator 14, an input rotation speed and an output rotation speed of the continuously variable transmission 1, an operation state of a mode switch, an operation state of a manual shift device, an acceleration in a longitudinal direction of the vehicle, a road gradient, A switch signal is input. The vehicle is equipped with a navigation system. This navigation system is configured in the same manner as conventionally known, and has a function of detecting the current position of the vehicle, a function of searching a planned travel route to the destination, and detecting and displaying a road condition of the planned travel route. It has a function to do. Signals are exchanged between the navigation system and the electronic control unit 37. Further, the electronic control unit 37 stores a map, an arithmetic expression, and the like that control the output of the engine 10, the transmission ratio and torque capacity of the continuously variable transmission 1, the engagement and release of the C1 clutch 6, and the pressure accumulation of the accumulator 14. ing.

  The operation of the hydraulic control device 32 described above will be described. When a clutch provided between the oil pump 11 and the engine 10 is engaged, when the engine 10 rotates, the oil pump 11 is driven to discharge the pressure oil. The engine 10 rotates either when the fuel is supplied to the engine 10 and rotates autonomously, or when the fuel supply and ignition are stopped and the vehicle 10 is forcibly rotated by the running inertial force of the vehicle. Arise. That is, the oil pump 11 rotates to generate hydraulic pressure regardless of whether the engine 10 is driven or the engine brake is driven. The hydraulic pressure thus generated is regulated to a predetermined low hydraulic pressure by the pressure regulating valve 12 and then supplied to the torque converter 7 via the control valve 8 and also to the lubricated portion 9.

  On the other hand, since the oil pump 11 generates a hydraulic pressure corresponding to the operating state of the engine 10, the discharge pressure of the oil pump 11 becomes high during sudden acceleration or when a large engine braking force is generated. The high oil pressure generated in such a case pushes the check valve 13 open and is supplied to the accumulator 14. Further, since the check valve 13 is closed when the discharge pressure of the oil pump 11 is lower than the hydraulic pressure in the accumulator 14, the high hydraulic pressure supplied to the accumulator 14 is stored here.

  The torque capacity of the continuously variable transmission 1 is controlled so as to prevent the belt 35 from slipping, and this is set by the clamping pressure corresponding to the hydraulic pressure supplied to the actuator 5 of the driven pulley 3. More specifically, the required driving force is determined based on the accelerator opening, the throttle opening, and the like, and the target engine torque is determined based on the required driving force. A target hydraulic pressure in the hydraulic chamber 5A is obtained based on parameters such as torque input to the continuously variable transmission 1 and prevention of slipping of the belt 35, and the actual hydraulic pressure in the hydraulic chamber 5A is calculated based on the target hydraulic pressure. Is controlled. A map or calculation formula for obtaining the target hydraulic pressure of the hydraulic chamber 5A based on these parameters is stored in advance in the electronic control unit 37. For example, when the torque input to the continuously variable transmission 1 increases, control for increasing the hydraulic pressure in the hydraulic chamber 5A is performed. In the hydraulic control device 32 shown in FIG. 2, the supply-side electromagnetic on-off valve DSS1 communicating with the actuator 5 of the driven pulley 3 is opened, the discharge-side electromagnetic on-off valve DSS2 is closed, and the hydraulic pressure is supplied to the hydraulic chamber 5A. The hydraulic pressure in the hydraulic chamber 5A can be increased. In this way, the torque capacity of the continuously variable transmission 1 is increased.

  On the other hand, when the torque input to the continuously variable transmission 1 decreases, control for decreasing the hydraulic pressure in the hydraulic chamber 5A is performed. In the hydraulic control device 32 shown in FIG. 2, the supply-side electromagnetic on-off valve DSS1 communicating with the actuator 5 of the driven pulley 3 is closed, the discharge-side electromagnetic on-off valve DSS2 is opened, and oil is discharged from the hydraulic chamber 5A. The oil pressure of 5A can be reduced. In this way, the torque capacity of the continuously variable transmission 1 is reduced. When the torque input to the continuously variable transmission 1 is constant, the supply-side electromagnetic on-off valve DSS1 is closed and the discharge-side electromagnetic on-off valve DSS2 is closed, so that the oil is enclosed in the hydraulic chamber 5A. The capacity is controlled to be constant.

  Next, control of the gear ratio in the continuously variable transmission 1 will be described. First, the required driving force in the vehicle is determined based on the vehicle speed and the accelerator pedal operation state (accelerator opening), and the target engine output is determined based on the required driving force. Further, when the actual engine output is controlled based on the target engine output, the target engine speed and the target engine output are determined so that the operating state of the engine 10 is along the optimum fuel consumption line. Then, the gear ratio of the continuously variable transmission 1 is controlled so that the actual engine speed approaches the target engine speed. The speed ratio of the continuously variable transmission 1 is controlled by controlling the flow rate of the pressure oil in the hydraulic chamber 4A. Specifically, based on the target transmission ratio of the continuously variable transmission 1, a map or an arithmetic expression for obtaining the target flow rate of the pressure oil in the hydraulic chamber 4A is stored in the electronic control unit 37, and based on the target flow rate. The actual flow rate of hydraulic oil in the hydraulic chamber 4A is controlled by opening and closing the supply-side electromagnetic on-off valve DSP1 and the discharge-side electromagnetic on-off valve DSP2.

  For example, in the case where the groove width of the drive pulley 2 is narrowed (the winding radius of the belt 35 is increased) in order to perform control (upshift) to relatively reduce the speed ratio of the continuously variable transmission 1, The supply-side electromagnetic on-off valve DSP1 is controlled to open and pressure oil is supplied to the actuator 4. On the other hand, when the groove width of the drive pulley 2 is increased (the winding radius of the belt 35 is decreased) in order to perform control (downshift) to relatively increase the gear ratio of the continuously variable transmission 1. The discharge-side electromagnetic on-off valve DSP2 is controlled to open and the oil is discharged from the actuator 4 to the oil pan 33. When the transmission ratio of the continuously variable transmission 1 is fixed, both the supply side electromagnetic on-off valve DSP1 and the discharge side electromagnetic on-off valve DSP2 are controlled to be closed, and the oil is confined in the hydraulic chamber 4A.

  Thus, basically, the gear ratio of the continuously variable transmission 1 is controlled so that the engine output is along the optimum fuel consumption line. On the other hand, a manual shift device operated by a driver is provided, and when the manual shift device is operated, control for changing the gear ratio of the continuously variable transmission 1 stepwise (upshift and downshift). It is comprised so that it can perform. When this manual shift device is operated by the driver, the gear ratio of the continuously variable transmission 1 is not controlled based on the optimum fuel consumption line, and the gear ratio of the continuously variable transmission 1 is selected by operating the manual shift device. The fixed gear ratio is fixed.

  In a steady running state in which the accelerator opening and the vehicle speed are maintained substantially constant, the transmission ratio of the continuously variable transmission 1 and the clamping pressure applied from the driven pulley 3 to the belt 35 are maintained constant. In that case, the electromagnetic on-off valves DSP1, DSP2, DSS1, DSS2 for the continuously variable transmission 1 are controlled to be closed, and the pressure oil is sealed in the hydraulic chambers of the actuators 4, 5. In this state, there is no leakage of hydraulic pressure from the electromagnetic on-off valves DSP1, DSP2, DSS1, DSS2.

  Further, when the vehicle travels, the C1 clutch 6 is engaged, and the torque of the engine 10 is transmitted to the drive wheels 36. Therefore, since the C1 clutch 6 transmits a large torque required for traveling, the hydraulic pressure of the C1 clutch 6 is increased. That is, when the vehicle starts, the supply-side electromagnetic on-off valve DSC1 is energized to control the opening thereof, and the hydraulic pressure is supplied to the C1 clutch 6 to engage the C1 clutch 6. On the other hand, when the C1 clutch 6 is released, the discharge side electromagnetic on-off valve DSC2 is controlled to be opened and the pressure is released from the C1 clutch 6. The electromagnetic on / off valves DSC1 and DSC2 for the C1 clutch 6 also do not cause substantial leakage of hydraulic pressure, similar to the electromagnetic on / off valves DSP1, DSP2, DSS1 and DSS2 for the continuously variable transmission 1 described above. Is.

  In the hydraulic control device 32 shown in FIG. 2, the oil discharged from the oil pump 11 or the oil pump 28 is supplied to the hydraulic chambers 4A and 5A, the hydraulic chambers of the C1 clutch 6 and the like via the oil passage 15. be able to. Further, when the oil discharged from the oil pump 11 or the oil pump 28 is supplied to the oil passage 15, the solenoid valve 39 is controlled to connect the oil passage 15 and the pressure accumulating chamber of the accumulator 14. The oil pressure can be stored in the accumulator 14. Furthermore, after the hydraulic pressure is stored in the accumulator 14, if the solenoid valve 39 is controlled to shut off the oil passage 15 and the pressure accumulation chamber of the accumulator 14, the pressure in the accumulator 14 is not released to the oil passage 15. Further, after the hydraulic pressure is stored in the accumulator 14, the solenoid valve 39 is controlled to connect the oil passage 15 and the pressure storage chamber of the accumulator 14, and the pressure in the accumulator 14 is discharged to the oil passage 15 to provide the hydraulic chamber 4A. , 5A, C1 can be supplied to the hydraulic chamber of the clutch 6. At this time, control of the hydraulic pressure or the oil amount in the hydraulic chambers 4A, 5A and the C1 clutch 6 is performed by the electromagnetic on-off valves DSP1, DSS1, DSC1.

Next, an example of vehicle control including accumulator 14 pressure accumulation will be described based on the flowchart of FIG. First, it is determined whether or not the oil pump 11 or the oil pump 28 is being driven without consuming fuel of the engine 10 (step S1). For example, when the accelerator pedal is returned and the vehicle is coasting and the fuel cut control is performed by the engine 10, the kinetic energy of the vehicle is transmitted to the oil pump 11 via the engine 10, If the oil pump 11 is driven, an affirmative determination is made in step S1, the control in step S2 is performed, and the process returns to the start. Further, the vehicle travels coasting returned the accelerator pedal, and transmits when the fuel cut control is performed, the generator 3 1 Ri our kinetic energy of the vehicle via the engine 10 in the engine 10 In the case where the electric power is generated and the electric power is supplied to the electric motor 29 to drive the electric motor 29 and the electric oil pump 28 is driven, an affirmative determination is made in step S1 and the process proceeds to step S2.

  In step S2, the accumulator 14 is constantly accumulated so that the internal pressure of the accumulator 14 becomes the maximum pressure, and this control routine is terminated. The maximum pressure of the accumulator 14 is the upper limit value of the internal pressure determined from the specifications of the bladder or piston of the accumulator 14 or the pressure determined from the pressure resistance performance of the entire system. That is, the internal pressure when the oil is fully supplied to the pressure accumulation chamber of the accumulator 14 is the upper limit value. “Accumulator 14 always accumulates pressure” means that the solenoid valve 39 is controlled to connect the oil passage 15 and the accumulator 14 accumulator 14, and the oil pressure of the accumulator 14 is increased regardless of the oil pressure of the oil passage 15. It means to store.

On the other hand, if fuel is supplied to the engine 10 and autonomously rotates at the time of determination in step S1, and the oil pump 11 is driven by the power of the engine 10, a negative determination is made in step S1. . Further, fuel is supplied to the engine 10 to rotate autonomously, and the generator 31 generates electric power with the power of the engine 10, and the electric power is supplied to the electric motor 29 to drive the electric motor 29, and the electric oil pump 28. Is also determined negative in step S1.

As described above, when a negative determination is made in step S1, it is determined whether or not the vehicle is traveling because the engine torque is transmitted to the drive wheels (step S3). If an affirmative determination is made in step S3, the criteria oil pressure to start accumulating in the accumulator 14 to change according to the vehicle speed (step S4), and returns to the start.

The control in step S4 will be specifically described. When the accelerator pedal is depressed while the vehicle 1 is running and the continuously variable transmission 1 performs a downshift (kickdown), it is necessary to increase the hydraulic pressure in the hydraulic chamber 5A. The required pressure depends on the vehicle speed. Different. Therefore, the map of FIG. 3 is stored in the electronic control unit 37 in order to obtain the necessary pressure from the vehicle speed. In the map of FIG. 3, the horizontal axis indicates the vehicle speed, and the vertical axis indicates the required pressure. The higher the vehicle speed, the higher the required pressure. Here, the required pressure is a value corresponding to the target hydraulic pressure in the hydraulic chamber 5A, and the required pressure is obtained from the vehicle speed at that time. Then, in step S4, the criteria hydraulic you start the accumulator in the accumulator 14 is set to a value greater than necessary pressure in FIG. The reference hydraulic pressure is a threshold value for determining whether or not to accumulate pressure in the accumulator 14. If the oil pressure in the oil passage 15 is equal to or higher than the reference oil pressure, pressure accumulation in the accumulator 14 is performed and the oil pressure in the oil passage 15 is increased. If it is less than the reference oil pressure, no pressure is accumulated in the accumulator 14.

  On the other hand, if a negative determination is made in step S3, the driver prefers that the vehicle is stopped on an uphill road or that the current driver (driver) suddenly starts the stopped vehicle. It is determined whether or not any of the conditions is satisfied (step S5). Whether the vehicle is stopped on an uphill road can be determined from a signal from a road gradient sensor or an acceleration sensor. Alternatively, it is possible to determine whether the vehicle is stopped on an uphill road using the map information of the navigation system. Whether or not the driver prefers sudden start can be determined based on the amount of depression of the accelerator pedal or the depression speed of the accelerator pedal. Here, the sudden start includes a stall start in addition to a case where the accelerator pedal depression speed is relatively fast or a case where the accelerator pedal depression amount is relatively large. In this method, the brake pedal and the accelerator pedal are depressed simultaneously to increase the engine speed relatively, and then the brake pedal is returned to start suddenly.

  If the determination in step S5 is affirmative, the required pressure in the hydraulic chamber of the continuously variable transmission 1 or the C1 clutch 6 is higher than that in step S4. Is set high (step S6), and the process returns to the start. The reference hydraulic pressure set in step S6 is a value obtained by experiment or simulation in consideration of conditions such as road gradient, accelerator pedal operation state at sudden start, and is mapped to the electronic control unit 37. Is remembered. Further, the reference oil pressure set in step S6 is higher than the reference oil pressure set in step S4.

  On the other hand, at the time of determination in step S5, it is detected that the vehicle is stopped on a flat road and the engine 10 is idling, or that the vehicle is stopped and the engine 10 is stopped. When the determination is negative in step S5, the reference hydraulic pressure at which the accumulator 14 starts accumulating is set relatively low (step S7), and the process returns to the start. The flat road has a relatively small road gradient compared to the uphill road. And a negative determination in step S5 means that the torque transmitted by the power transmission device is relatively low. That is, the target hydraulic pressure of the hydraulic chamber 5A and the target hydraulic pressure of the hydraulic chamber of the C1 clutch 6 are lower than when the process proceeds to step S4. Therefore, even if the accumulator 14 starts accumulating from a relatively low reference hydraulic pressure in step S7, there is no shortage of pressure oil in the hydraulic chambers of the hydraulic chamber 5A and the C1 clutch 6. This is the reason why the reference oil pressure set in step S7 is lower than the reference oil pressure set in step S4. The reference hydraulic pressure set in step S7 is also stored in advance in the electronic control unit 37.

  Note that the meaning of the reference oil pressure in the control in steps S6 and S7 is the same as the meaning of the reference oil pressure in step S4. That is, when the control of steps S4, S6, and S7 is performed, when the oil pressure in the oil passage 15 is less than the reference oil pressure, the solenoid valve 39 is controlled to shut off the oil passage 15 and the accumulator 14 accumulator. No pressure accumulation by 14 is performed. On the contrary, if the oil pressure in the oil passage 15 is equal to or higher than the reference oil pressure, the solenoid valve 39 is controlled to connect the oil passage 15 and the pressure accumulating chamber of the accumulator 14, and the accumulator 14 accumulates pressure. In addition, in the control for proceeding to steps S4, S6, and S7 and accumulating with the accumulator 14, the control is performed to drive the stopped oil pump and to accumulate the hydraulic pressure of the oil discharged from the oil pump in the accumulator 14. And a control for accumulating oil discharged from the driven oil pump in the accumulator 14 from a state in which the oil pump is driven but no pressure is accumulated in the accumulator 14.

  As described above, when the control of FIG. 1 is executed, under the condition that the hydraulic pressure can be stored in the accumulator 14 without consuming fuel in the engine 10, the pressure is always stored until the internal pressure of the accumulator 14 reaches the maximum pressure. When accumulating the hydraulic pressure of oil discharged from at least one of the oil pump 11 driven by the power of 10 or the oil pump 28 driven by the power of the electric motor 29, the accumulator 14 is always accumulated. It is not done. Specifically, the reference hydraulic pressure is obtained based on at least one of the vehicle speed, road gradient, and driver characteristics, and when the oil pressure in the oil passage 15 is equal to or higher than the reference hydraulic pressure, the accumulator 14 stores the pressure. On the other hand, when the oil pressure in the oil passage 15 is less than the reference oil pressure, no pressure is accumulated in the accumulator 14. Therefore, the power of the engine 10 that drives the oil pump 11 or the power of the engine 10 that indirectly drives the oil pump 11 can be suppressed from being unnecessarily consumed, and an increase in fuel consumption in the engine 10 is suppressed. it can.

  In the above description, the example in which the reference hydraulic pressure is obtained mainly based on the target hydraulic pressure in the hydraulic chamber 5A has been described. However, the reference hydraulic pressure may be obtained based on the target hydraulic pressure in the hydraulic chamber of the C1 clutch. Good. This C1 clutch is also a mechanism for controlling the torque capacity, and the target hydraulic pressure becomes relatively higher as the target torque is relatively higher. Then, a map or an arithmetic expression in which the reference hydraulic pressure becomes relatively higher as the target hydraulic pressure of the C1 clutch is relatively higher may be stored in the electronic control device 37 in advance.

  Here, the correspondence between the functional means shown in FIG. 1 and the configuration of the present invention will be described. Step S3 corresponds to the determination means of the present invention, and step S4 corresponds to the first pressure accumulation of the present invention. It corresponds to the control means, and steps S5, S6 and S7 correspond to the second control means of the present invention. Further, the correspondence relationship between the configuration shown in FIG. 2 and the configuration of the present invention will be described. The engine 10 corresponds to the power source of the present invention, and the continuously variable transmission 1 corresponds to the power transmission device of the present invention. The hydraulic chambers 4A and 5A and the hydraulic chamber of the clutch C1 correspond to the hydraulic chamber of the present invention, the oil pumps 11 and 28 correspond to the oil pump of the present invention, and the oil passage 15 corresponds to the supply of the present invention. The accumulator 14 corresponds to a path and the accumulator of the present invention.

  The transmission ratio of the continuously variable transmission is controlled based on the hydraulic pressure in the hydraulic chamber of the drive pulley, and the torque of the continuously variable transmission is determined based on the flow rate of pressure oil in the hydraulic chamber of the driven pulley. The flowchart of FIG. 1 can also be executed in a vehicle configured to be controlled. For example, a map or an arithmetic expression can be stored in advance in the electronic control device so that the reference hydraulic pressure set in each step can be set based on the target hydraulic pressure of the hydraulic chamber that controls the gear ratio. Alternatively, a map or an arithmetic expression can be stored in advance in the electronic control device so that the reference hydraulic pressure set in each step can be set based on the target flow rate of the hydraulic chamber that controls the torque. Specifically, the reference hydraulic pressure may be relatively increased as the target flow rate is relatively increased.

  Further, the transmission ratio of the continuously variable transmission is controlled based on the hydraulic pressure of the hydraulic chamber of the drive pulley, and the torque of the continuously variable transmission is controlled based on the hydraulic pressure of the hydraulic chamber of the driven pulley. Even in a vehicle configured as described above, the flowchart of FIG. 1 can be executed. In this case, a map and an arithmetic expression should be stored in advance in the electronic control unit so that the reference hydraulic pressure set in each step can be set based on the higher target hydraulic pressure of the hydraulic chambers in both hydraulic chambers. That's fine.

  Further, the transmission ratio of the continuously variable transmission is controlled based on the flow rate of pressure oil in the hydraulic chamber of the drive pulley, and the continuously variable transmission is performed based on the flow rate of pressure oil in the hydraulic chamber of the driven pulley. The flowchart of FIG. 1 can also be executed in a vehicle configured such that the torque of the machine is controlled. In this case, a map and an arithmetic expression should be stored in advance in the electronic control unit so that the reference hydraulic pressure set in each step can be set based on the higher target flow rate of the target flow rates of both hydraulic chambers. That's fine. Specifically, the reference hydraulic pressure may be relatively increased as the target flow rate is relatively increased.

  Further, the control example of FIG. 1 is also provided in a vehicle in which a motor / generator is provided as a power source for transmitting torque to the drive wheels and the oil pump is driven by the torque of the motor / generator. Can be executed. In this case, in step S1, it is determined whether or not the vehicle is coasting and the kinetic energy is transmitted to the oil pump to be driven. If the determination in step S1 is affirmative, step S2 is performed. Proceed to In step S2, since the electric power for driving the motor / generator is not consumed, the accumulator always accumulates pressure.

  On the other hand, if a negative determination is made in step S1, it is determined in step S3 whether or not the vehicle is running based on the torque of the motor / generator. If a positive determination is made in step S3, the process proceeds to step S4. On the other hand, if the vehicle is stopped on a flat road and the motor / generator is stopped at the time of determination in step S5, a negative determination is made in step S5, and the process proceeds to step S7. Thus, even in a vehicle provided with a motor / generator for transmitting torque to drive wheels, the control example of FIG. 1 can be executed. When the control example of FIG. 1 is executed in the vehicle, steps S4 and S6 are executed. , S7 can also prevent the power consumption of the motor / generator driving the oil pump from increasing unnecessarily. In the vehicle shown in FIG. 2, a plurality of oil pumps are provided, but in a vehicle provided with one oil pump that discharges the pressure oil supplied to the oil passage to which the accumulator is connected. In addition, the control example of FIG. 1 can be executed.

  In step S5, it is determined whether or not the road gradient at which the vehicle is stopped is equal to or greater than a predetermined value. If the determination in step S5 is affirmative, the process proceeds to step S6. When a negative determination is made in S5, the process may proceed to step S7. Further, the flowchart of FIG. 1 shows a routine for determining whether or not the vehicle is traveling and obtaining the reference hydraulic pressure based on the vehicle speed when the vehicle is traveling. It is also possible to employ a routine that proceeds to step S4 without making a determination in step S3 if a negative determination is made. In this case, steps S5, S6 and S7 are not performed.

  Further, the flowchart of FIG. 1 shows a routine for determining whether or not the vehicle is traveling and obtaining the reference hydraulic pressure based on the vehicle speed when the vehicle is traveling. It is also possible to employ a routine that proceeds to step S5 without making the determination of step S3 if a negative determination is made. In this case, step S4 is not performed. Furthermore, when a negative determination is made in step S1, the process proceeds to step S5 without performing step S3. In step S5, only one of the road gradient or the driver characteristic is determined, and the determination result is obtained. A routine that proceeds to step S6 or step S7 based on this can also be adopted.

  Here, the correspondence between the functional means shown in FIG. 1 and the configuration of the present invention will be described. Step S3 corresponds to the determination means of the present invention, and steps S4, S5, S6, and S7 are This corresponds to the pressure accumulation control means of the invention. Further, the correspondence relationship between the configuration shown in FIG. 2 and the configuration of the present invention will be described. The engine 10 corresponds to the power source of the present invention, and the continuously variable transmission 1 corresponds to the power transmission device of the present invention. The hydraulic chambers 4A and 5A and the hydraulic chamber of the clutch C1 correspond to the hydraulic chamber of the present invention, the oil pumps 11 and 28 correspond to the oil pump of the present invention, and the oil passage 15 corresponds to the supply of the present invention. The accumulator 14 corresponds to the path, the accumulator 14 corresponds to the accumulator of the present invention, and the driving wheel 36 corresponds to the driving wheel of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Continuously variable transmission, 4A, 5A ... Hydraulic chamber, 10 ... Engine, 11 ... Oil pump, 14 ... Accumulator, 28 ... Electric oil pump, 36 ... Drive wheel

Claims (3)

A power transmission device provided in a path from the power source of the vehicle to the driving wheel; a hydraulic chamber that is supplied with oil to control a power transmission state of the power transmission device; Vehicle hydraulic pressure having an oil pump that discharges oil supplied to the chamber, and an accumulator that is provided in an oil supply path from the oil pump to the hydraulic chamber and that stores oil pressure of oil discharged from the oil pump In the control device ,
Car speed, or characteristic of the driver at start of the vehicle or on the basis of at least one condition of the road gradient of where the vehicle is located, to change the reference hydraulic pressure to start accumulating in the accumulator for example Bei the accumulator control means,
A vehicular hydraulic control device configured to store pressure in the accumulator when the hydraulic pressure in the supply oil passage is equal to or higher than the reference hydraulic pressure . Determining means for determining whether the vehicle is running with the power of the power source or whether the vehicle is stopped;
It said accumulator control means, when the vehicle is determined to be traveling by the power of the power source, and means for changing said reference hydraulic pressure based on the vehicle speed, the vehicle is determined to have stopped If the, according to claim 1, characterized in that it comprises means for varying said reference hydraulic pressure based on the road slope location characteristics of the driver or the vehicle, it is positioned at the start of the previous SL vehicle Hydraulic control device for vehicles.   The pressure accumulation control means is a means for relatively increasing the reference oil pressure as the vehicle speed is relatively high, or a means for relatively increasing the reference oil pressure as a driver prefers sudden start, or The vehicle hydraulic control device according to claim 1, further comprising means for relatively increasing the reference hydraulic pressure as the road gradient is relatively large.

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