JP4254516B2 - Hydraulic control device for belt type continuously variable transmission - Google Patents

Description

  The present invention relates to a hydraulic control device for a belt-type continuously variable transmission in which a belt is wound around a plurality of pulleys.

  2. Description of the Related Art Conventionally, there has been known a control in which an operating state of an engine is brought close to an optimum state by providing a continuously variable transmission on the output side of the engine and controlling a speed ratio of the continuously variable transmission continuously. As such a continuously variable transmission, a belt-type continuously variable transmission and a toroidal-type continuously variable transmission are known, and an example of a belt-type continuously variable transmission is described in Patent Document 1 below. The belt type continuously variable transmission described in Patent Document 1 includes a driving pulley and a driven pulley on which a belt is wound. In addition, hydraulic servo devices that vary the belt winding diameter of the driving pulley and the driven pulley are provided. Each hydraulic servo device has an oil chamber, and a hydraulic circuit that supplies pressure oil discharged from the first oil pump to each oil chamber is formed. A pressure regulating valve for regulating the discharge pressure of the first oil pump is provided, and the pressure oil regulated to the line pressure by the pressure regulating valve passes through the one valve, respectively, and the oil chamber of the driving pulley and It is configured to be supplied to the oil chamber of the driven pulley.

Furthermore, in the direction in which pressure oil is supplied from the first oil pump to each oil chamber, an oil passage that connects the oil chambers is provided on the downstream side of each one valve. A second oil pump for discharging oil is provided. Then, by driving the second oil pump, the hydraulic pressure is supplied and discharged between the oil chamber of the driving pulley and the oil chamber of the driven pulley. Specifically, when pressure oil in the oil chamber of the driving pulley is supplied to the oil chamber of the driven pulley, the oil pressure in the oil chamber of the driving pulley decreases and the oil pressure in the oil chamber of the driven pulley increases. When the pressure oil in the oil chamber of the driven pulley is supplied to the oil chamber of the driving pulley while the speed is changed to the low speed ratio (low), the oil pressure in the oil chamber of the driving pulley increases and the oil in the driven pulley is increased. It is said that the hydraulic pressure of the chamber decreases and the gear ratio is shifted to a high speed ratio (high). A hydraulic control device for a belt type continuously variable transmission is also described in Patent Document 2 below.
Japanese Patent No. 2975082 Special Table 2002-523711

  However, in the hydraulic control device for the belt-type continuously variable transmission described in Patent Document 1 above, due to variations in the supply characteristics of the pressure oil by the second oil pump and oil leakage from the oil chamber of each pulley, etc. However, there is a problem that it is difficult to control the shift of the belt type continuously variable transmission.

  The present invention has been made against the background described above, and is a belt-type continuously variable transmission capable of improving the control accuracy of supply and discharge of pressure oil in the hydraulic chambers of the primary pulley and the secondary pulley. An object of the present invention is to provide a hydraulic control device.

In order to achieve the above object, the invention according to claim 1 is directed to a primary pulley and a secondary pulley around which a belt is wound, and a primary hydraulic chamber and a secondary pulley that control a winding state of the belt in the primary pulley and the secondary pulley. A hydraulic chamber, a first oil pump for supplying pressure oil to the primary hydraulic chamber and the secondary hydraulic chamber, and a first path provided in a path for supplying pressure oil from the first oil pump to the primary hydraulic chamber. A check valve, a second check valve provided in a path for supplying pressure oil from the first oil pump to the secondary hydraulic chamber, and the primary hydraulic chamber and the secondary hydraulic chamber, In a hydraulic control device for a belt-type continuously variable transmission having a second oil pump for supplying and discharging pressure oil to the first oil pump, A first pressure control valve that controls the hydraulic pressure of the pressure oil supplied to the primary hydraulic chamber, and a second pressure control that controls the hydraulic pressure of the pressure oil supplied from the first oil pump to the secondary hydraulic chamber. and the valve is provided separately Rutotomoni, an engine for driving the first oil pump, an electric motor for driving the second oil pump, when the engine is stopped, the primary hydraulic chamber And the secondary hydraulic chamber are stopped from supplying and discharging pressure oil to each other, and the oil in the oil holding portion is sucked by the second oil pump, and the pressure discharged from the second oil pump the oil and is characterized that you and the first switching device to supply to the input side of the input side and the second pressure control valve of the pressure control valve is provided.

  According to a second aspect of the present invention, in addition to the configuration of the first aspect, a determination means for determining whether or not a function of one of the first oil pump and the second oil pump has deteriorated. When the function of one of the oil pumps is reduced, an oil pump selection means for controlling the supply and discharge of the pressure oil in the primary hydraulic chamber and the secondary hydraulic chamber is performed by the function of the normal oil pump. It is characterized by having.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, the kinetic energy of the pressure oil traveling between the primary hydraulic chamber and the secondary hydraulic chamber is converted into electric energy based on the traveling state of the vehicle. It has an energy recovery means for converting and recovering the electrical energy.

According to a fourth aspect of the present invention, in addition to the configuration of the third aspect , the energy recovery means controls the recovery of the electric energy when a gear ratio between the primary pulley and the secondary pulley changes gently. On the other hand, when the gear ratio between the primary pulley and the secondary pulley changes abruptly, it is further provided with a function of prohibiting control to recover the electric energy. is there.

The invention according to claim 5 includes a primary pulley and a secondary pulley around which a belt is wound, a primary hydraulic chamber and a secondary hydraulic chamber that control a winding state of the belt in the primary pulley and the secondary pulley, the primary hydraulic chamber, A first oil pump for supplying pressure oil to the secondary hydraulic chamber; a first check valve provided in a path for supplying pressure oil from the first oil pump to the primary hydraulic chamber; Pressure oil is supplied and discharged between a second check valve provided in a path for supplying pressure oil from the oil pump to the secondary hydraulic chamber, and the primary hydraulic chamber and the secondary hydraulic chamber. In a hydraulic control device for a belt-type continuously variable transmission having a second oil pump, the first hydraulic pump supplies the primary hydraulic chamber. A first pressure control valve that controls the hydraulic pressure of the pressure oil and a second pressure control valve that controls the hydraulic pressure of the pressure oil supplied from the first oil pump to the secondary hydraulic chamber are provided separately. It is and, first for discharging pressure oil path from the first oil pump to said first pressure control valve and a second pressure control valve, to the low pressure portion by way of the second oil pump And a second control mode in which pressure oil is transferred back and forth between the primary hydraulic chamber and the secondary hydraulic chamber via the second oil pump. , Comparing the work of the second oil pump when the first control mode is selected with the work of the second oil pump when the second control mode is selected, The work of the second oil pump And it is characterized in that it has a control mode selecting means for selecting a control mode.

  In the invention of each claim, “the belt winding state in the primary pulley and the secondary pulley” includes the clamping pressure applied to the belt from each pulley, the groove width in each pulley, the belt winding radius in each pulley, the belt This includes the capacity of torque transmitted via the belt, the tension of the belt, the gear ratio between the primary pulley and the secondary pulley, and the like. According to a third aspect of the present invention, the oil holding portion is provided separately from the primary hydraulic chamber and the secondary hydraulic chamber.

According to the first aspect of the present invention, the hydraulic pressure of the pressure oil supplied from the first oil pump to the primary hydraulic chamber is controlled by the first pressure control valve, and is supplied from the first oil pump to the secondary hydraulic chamber. The hydraulic pressure of the pressure oil is controlled by the second pressure control valve. The flow rate of the pressure oil supplied to the primary hydraulic chamber and the flow rate of the pressure oil supplied to the secondary hydraulic chamber are controlled by the second oil pump. That is, it is possible to share the hydraulic control and flow rate control of the pressure oil supplied to each hydraulic chamber between the first oil pump and the second oil pump, and the pressure in the primary hydraulic chamber and the secondary hydraulic chamber. Oil supply and discharge control accuracy is improved . According to the first aspect of the present invention, the first oil pump is driven by the engine, and the second oil pump is driven by the electric motor. In addition, when the engine is stopped, pressure oil is not supplied and discharged between the primary hydraulic chamber and the secondary hydraulic chamber, and the oil in the oil holding portion is sucked by the second oil pump, The pressure oil discharged from the second oil pump is supplied to the input side of the first pressure control valve and the input side of the second pressure control valve. Therefore, even when the engine is stopped, the hydraulic pressure of the pressure oil supplied to the primary hydraulic chamber is controlled by the first pressure control valve, and the hydraulic pressure of the pressure oil supplied to the secondary hydraulic chamber is changed to the second pressure chamber. It can be controlled by a control valve.

  According to the second aspect of the present invention, the same effect as that of the first aspect of the invention can be obtained, and even when the function of one of the oil pumps is reduced, the normal oil pump causes the hydraulic chamber to It is possible to supply the pressure oil or discharge the pressure oil from the hydraulic chamber to execute the shift control of the belt type continuously variable transmission.

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 oil traveling between the primary hydraulic chamber and the secondary hydraulic chamber based on the running state of the vehicle It is possible to convert the kinetic energy into electrical energy and recover the electrical energy.

According to the invention of claim 4, in addition to the same effect as that of the invention of claim 3, at the time of a sudden shift, the pressure oil is quickly moved back and forth between the primary hydraulic chamber and the secondary hydraulic chamber, and the shift response The decline in sex can be suppressed. Therefore, it is possible to achieve a balance between recoverability of electric energy and shift response.

According to the fifth aspect of the present invention, the hydraulic pressure of the pressure oil supplied from the first oil pump to the primary hydraulic chamber is controlled by the first pressure control valve, and is supplied from the first oil pump to the secondary hydraulic chamber. The hydraulic pressure of the pressure oil is controlled by the second pressure control valve. The flow rate of the pressure oil supplied to the primary hydraulic chamber and the flow rate of the pressure oil supplied to the secondary hydraulic chamber are controlled by the second oil pump. That is, it is possible to share the hydraulic control and flow rate control of the pressure oil supplied to each hydraulic chamber between the first oil pump and the second oil pump, and the pressure in the primary hydraulic chamber and the secondary hydraulic chamber. Oil supply and discharge control accuracy is improved. According to the invention of claim 5, the work amount of the second oil pump when the first control mode is selected, and the work amount of the second oil pump when the second control mode is selected. And the control mode with the smaller work amount of the second oil pump can be selected. Therefore, the efficiency of the second oil pump is improved.

  Next, the present invention will be described based on specific examples. FIG. 2 schematically shows an example of a power train and a control system of a vehicle Ve that is an example of the present invention. The power train shown here is configured such that the torque of the engine 1 is transmitted to the belt-type continuously variable transmission 4 via the fluid transmission device 9 and the forward / reverse switching device 8. The engine 1 has a crankshaft 70, and a torque converter is used as the fluid transmission device 9 connected to the crankshaft 70 in the embodiment of FIG. Hereinafter, the fluid transmission device 9 is referred to as a “torque converter 9”.

  The torque converter 9 has a pump impeller 11 and a turbine runner 12. A cylindrical portion 71 is continuous with the front cover 10, and the pump impeller 11 is formed at the end of the cylindrical portion 71 opposite to the front cover 10. The turbine runner 12 is disposed inside the cylindrical portion 71, and the pump impeller 11 and the turbine runner 12 are provided to face each other. The turbine runner 12 is connected to the shaft 50 so as to rotate integrally. The pump impeller 11 and the turbine runner 12 are provided with a large number of blades (not shown), and power is transmitted between the pump impeller 11 and the turbine runner 12 by the kinetic energy of oil.

  In addition, a stator 13 that selectively changes the flow direction of the fluid sent from the turbine runner 12 and flows into the pump impeller 11 is disposed in the inner peripheral portion of the pump impeller 11 and the turbine runner 12. . The stator 13 is connected to a predetermined fixed portion (casing) 15 via a one-way clutch 14.

  The torque converter 9 includes a lockup clutch 16. The lock-up clutch 16 is provided inside the cylindrical portion 71 and is arranged in parallel with the power transmission path from the front cover 10 to the shaft 50. In addition, a first hydraulic chamber 72 and a second hydraulic chamber 73 are formed inside the cylindrical portion 71. The lockup clutch 16 is attached so as to rotate integrally with the shaft 50 and is configured to be movable in the axial direction of the shaft 50. The operation of the lockup clutch 16 in the axial direction of the shaft 50 is controlled based on the correspondence between the hydraulic pressure in the first hydraulic chamber 72 and the hydraulic pressure in the second hydraulic chamber 73. Furthermore, a hydraulic control device 59 having a function of controlling the pressure of oil supplied to the first hydraulic chamber 72 and the second hydraulic chamber 73 is provided.

  The forward / reverse switching device 8 is a mechanism that is employed when the rotational direction of the engine 1 is limited to one direction, and the forward / reverse switching device 8 is configured to move the primary shaft 51 with respect to the rotational direction of the shaft 50. A function to switch the rotation direction is provided. The forward / reverse switching device 8 has a function of connecting the shaft 50 and the primary shaft 51 to a state where power can be transmitted and a function of blocking power transmission between the shaft 50 and the primary shaft 51. Yes.

  In the example shown in FIG. 2, a double pinion type planetary gear mechanism is employed as the forward / reverse switching device 8. That is, a sun gear 17 that rotates integrally with the shaft 50 and a ring gear 18 that is arranged concentrically with the sun gear 17 are provided, and a pinion gear 19 that meshes with the sun gear 17 and a pinion gear between the sun gear 17 and the ring gear 18. 19 and another pinion gear 20 meshed with the ring gear 18 are arranged, and the pinion gears 19 and 20 are held by a carrier 21 so as to rotate and revolve freely.

  Further, a forward clutch 22 that connects the sun gear 17 and the shaft 50 and the carrier 21 so as to be integrally rotatable is provided. A reverse brake 23 that reverses the rotation direction of the primary shaft 51 with respect to the rotation direction of the shaft 50 by selectively fixing the ring gear 18 is provided. A hydraulic servo mechanism (not shown) for controlling engagement / release of the forward clutch 22 and the reverse brake 23 is provided, and the hydraulic pressure of the hydraulic servo mechanism is controlled by a hydraulic control device 59. The primary shaft 51 and the carrier 21 are connected so as to rotate integrally.

  The belt type continuously variable transmission 4 includes a primary pulley 24 and a secondary pulley 25 that are arranged in parallel to each other. First, the primary pulley 24 is configured to rotate integrally with the primary shaft 51, and the primary pulley 24 has a fixed sheave 52 and a movable sheave 53 connected to a piston (not shown). . A hydraulic actuator (hydraulic servo mechanism) 26 that moves the movable sheave 53 in the axial direction of the primary shaft 51 is provided.

  On the other hand, the secondary pulley 25 is configured to rotate integrally with the secondary shaft 55, and the secondary pulley 25 has a fixed sheave 54 and a movable sheave 56 connected to a piston (not shown). is doing. Further, a hydraulic actuator (hydraulic servo mechanism) 27 that moves the movable sheave 56 in the axial direction of the secondary shaft 55 is provided. Further, an annular belt 28 is wound around the primary pulley 24 and the secondary pulley 25. Further, the supply and discharge of pressure oil in the hydraulic chamber (described later) of the actuator 26 and the hydraulic chamber (described later) of the actuator 27 are controlled by a hydraulic control device 59. The differential 6 is connected to the secondary shaft 55 via the gear transmission 29, and the wheel (front wheel) 2 is connected to the differential 6.

  Next, a control system for the vehicle Ve shown in FIG. 2 will be described. First, an electronic control unit (ECU) 34 is provided. The electronic control unit 34 is a microcomputer having an arithmetic processing unit (CPU or MPU), a storage unit (RAM and ROM), and an input / output interface. It is configured. The electronic control unit 34 includes a signal from the engine rotational speed sensor 30, a signal from the turbine rotational speed sensor 31 that detects the rotational speed of the turbine runner 12, a signal from the input rotational speed sensor 32 that detects the rotational speed of the primary shaft 51, A signal from the output rotation speed sensor 33 that detects the rotation speed of the secondary shaft 55, a signal from the accelerator opening sensor 57, a signal from the shift position sensor 60, a signal from the brake switch 74, a signal from the ignition switch 58, and the like are input. The gear ratio of the belt-type continuously variable transmission 4 is calculated based on the signal of the input rotational speed sensor 32 and the signal of the output rotational speed sensor 33, and the vehicle speed is calculated based on the signal of the output rotational speed sensor 33. Is done.

  The shift position sensor 60 detects an operation state of a shift position selection device (not shown) operated by an occupant of the vehicle Ve. For example, the shift position sensor 60 detects a parking position, a reverse position, a neutral position, a drive position, a low position, and the like. On the other hand, from the electronic control unit 34, a signal for controlling the engine 1, a signal for controlling the hydraulic pressure control unit 59, a signal for controlling the belt-type continuously variable transmission 4, a signal for controlling the lockup clutch 16, A signal for controlling the advance switching device 8, a signal for controlling a motor (described later), a switching solenoid valve (described later), and the like are output.

  In the vehicle Ve configured as described above, when the engine 1 is operated, torque output from the engine 1 is transmitted to the wheels via the torque converter 9, the forward / reverse switching device 8, and the belt type continuously variable transmission 4. 2 is transmitted. Further, the electronic control unit 34 stores a lockup clutch control map. Based on the lockup clutch control map, the transmission torque capacity of the lockup clutch 16 (in other words, engagement hydraulic pressure, engagement pressure, engagement State) is controlled, and the lock-up clutch 16 is released (specifically fully released) or slipped or engaged (specifically fully engaged).

  Next, the control of the forward / reverse switching device 8 will be described. When the shift position sensor 60 detects a low position or a drive position, the forward clutch 22 of the forward / reverse switching device 8 is engaged and the reverse brake 23 is released. Then, the shaft 50 and the carrier 21 rotate integrally, the torque of the shaft 50 is transmitted to the primary shaft 51, and the torque of the primary shaft 51 is transmitted to the wheels 2, so that the driving force for moving the vehicle Ve forward is generated. appear. At this time, the shaft 50 and the primary shaft 51 rotate in the same direction.

  On the other hand, when the reverse position is detected by the shift position sensor 60, the forward clutch 22 is released and the reverse brake 23 is engaged. Then, when the engine torque is transmitted to the sun gear 17, the ring gear 18 serves as a reaction force element, and the torque of the sun gear 17 is transmitted to the primary shaft 51 via the carrier 21. When the torque of the primary shaft 51 is transmitted to the wheels 2, a driving force in a direction for moving the vehicle Ve backward is generated. In this case, the shaft 50 and the primary shaft 51 rotate in opposite directions. When the neutral position or the parking position is selected, the forward clutch 22 and the reverse brake 23 are released, and the power transmission between the shaft 50 and the primary shaft 51 is interrupted.

  Next, the control of the belt type continuously variable transmission 4 will be described. As described above, the engine torque is transmitted to the primary shaft 51, and the belt type continuously variable transmission is performed based on various signals input to the electronic control unit 34 and data stored in advance in the electronic control unit 34. The machine 4 is controlled. That is, the axial thrust applied to the movable sheave 53 and the axial thrust applied to the movable sheave 56 are controlled, and the winding state of the belt 28 in the primary pulley 24 and the secondary pulley 25 is controlled. Specifically, when the hydraulic pressure in the hydraulic chamber of the actuator 26 increases, the thrust applied to the movable sheave 53 via the piston increases, and when the hydraulic pressure in the hydraulic chamber of the actuator 26 decreases, the movable sheave 53 The thrust applied to is reduced. When the hydraulic pressure in the hydraulic chamber of the actuator 27 increases, the thrust applied to the movable sheave 56 via the piston increases, and when the hydraulic pressure in the hydraulic chamber of the actuator 27 decreases, it is applied to the movable sheave 56. Thrust is reduced.

  Depending on the thrust between the primary pulley 24 and the belt 28 according to the thrust of the movable sheave 53, and according to the relative relationship between the sandwiching pressure applied from the secondary pulley 25 to the belt 28 according to the thrust of the movable sheave 56. Thus, the winding radius of the belt 28 in the primary pulley 24 and the secondary pulley 25 is controlled, and the torque capacity of the belt 28 is controlled. The gear ratio of the belt type continuously variable transmission 4 is determined according to the winding radius of the belt 28. The gear ratio of the belt type continuously variable transmission 4 is the ratio between the rotational speed of the primary pulley 24 and the rotational speed of the secondary pulley 25. In other words, the speed change is a speed change in which the winding radius of the belt 28 in the primary pulley 24 is increased and the winding radius of the belt 28 in the secondary pulley 25 is reduced. On the other hand, a speed change in which the winding radius of the belt 28 in the primary pulley 24 is reduced and the winding radius of the belt 28 in the secondary pulley 25 is increased is a reduction speed change. Furthermore, when both the winding radius of the belt 28 in the primary pulley 24 and the winding radius of the belt 28 in the secondary pulley 25 do not change, the gear ratio is controlled to be substantially constant.

  In the case of executing the deceleration shift as described above, the first control for increasing the thrust applied to the movable sheave 53 and the thrust applied to the movable sheave 56 or the thrust applied to the movable sheave 53 is performed. A second control that lowers the thrust applied to the movable sheave 56, or a third control that lowers the thrust applied to the movable sheave 53 and increases the thrust applied to the movable sheave 56. Either can be selected. In addition, when executing the speed increasing shift, the thrust applied to the movable sheave 53 is increased, and the first control for increasing the thrust applied to the movable sheave 56, or the thrust applied to the movable sheave 53 is decreased. And the second control for reducing the thrust applied to the movable sheave 56, or the third control for increasing the thrust applied to the movable sheave 53 and reducing the thrust applied to the movable sheave 56. Can be selected. When the gear ratio is controlled to be substantially constant, control for making the thrust applied to the movable sheaves 53 and 56 substantially constant is executed.

  Next, a configuration example of a hydraulic circuit constituting a part of the above-described hydraulic control device 59 will be described with reference to FIG. The first embodiment corresponds to the first and second aspects of the invention. The hydraulic circuit 80 shown in FIG. 1 mainly shows a portion that controls the belt type continuously variable transmission 4. First, the actuator 26 has a primary hydraulic chamber 81, and the actuator 27 has a secondary hydraulic chamber 82. An oil pump 83 that discharges the pressure oil supplied to the primary hydraulic chamber 81 and the secondary hydraulic chamber 82 is provided. The oil pump 83 is driven by the power of the engine 1 and sucks oil from the oil pan 84. An oil passage 85 to which the pressure oil discharged from the oil pump 83 is supplied is provided. The pressure oil in the oil passage 85 is supplied to the hydraulic servo mechanism and the torque converter 9 of the forward / reverse switching device 8.

  The oil passage 85 is connected to a primary sheave pressure control valve (pressure reducing valve) 86, and the oil passage 85 is provided with an oil pump check valve 87 and a first check valve 88. Here, in the flow direction of the pressure oil in which the pressure oil discharged from the oil pump 83 is supplied to the primary sheave pressure control valve 86 via the oil passage 85, the oil pump check valve 87 is first. The check valve 88 is disposed upstream of the check valve 88. Further, an oil passage 89 is provided, which is an oil passage 89 that branches from between the oil pump check valve 87 and the first check valve 88, and the line pressure control valve 90 is provided in the oil passage 89. A secondary sheave pressure control valve (pressure reducing valve) 91 is connected.

  The oil pump check valve 87 allows the pressure oil to be discharged from the oil pump 83 to the oil passage 85, and the pressure oil in the vicinity of the connection portion with the oil passage 89 is the oil passage 85. 83 has a function of preventing backflow. Further, the first check valve 88 is an oil passage 85, and allows the pressure oil in the vicinity of the connection portion with the oil passage 89 to be supplied to the primary sheave pressure control valve 86 side, thereby performing primary sheave pressure control. The pressure oil on the valve 86 side is the oil passage 85, and has a function of preventing backflow in the vicinity of the connection portion with the oil passage 89.

  The line pressure control valve 90 has an input port 92, a drain port 93 and a feedback port 94, and the pressure oil discharged from the oil passage 95 to the drain port 93 according to the oil pressure of the oil passages 85 and 89. The flow rate is controlled. The input port 92 is connected to the oil passage 89 via the oil passage 95. The drain port 93 is connected to the oil pan 84. The oil passage 89 is provided with a second check valve 96. The oil passage 95 is an oil passage 89 and is connected between the second check valve 96 and the oil passage 85.

  Further, the second check valve 96 is an oil passage 89 and allows the pressure oil in the vicinity of the connection portion with the oil passage 95 to be supplied to the secondary sheave pressure control valve 91 side, and the secondary sheave pressure control. The pressure oil on the valve 91 side is an oil passage 89, and has a function of preventing backflow in the vicinity of the connection portion with the oil passage 95.

  The configuration of the primary sheave pressure control valve 86 will be described with reference to FIG. The primary sheave pressure control valve 86 includes a spool 97 that can linearly reciprocate, and an elastic member 98 that biases the spool 97 in a predetermined direction. Land portions 99 and 100 are formed in the spool 97. The primary sheave pressure control valve 86 has an input port 101, an output port 102, a drain port 103, a feedback port 104, and a signal pressure port 105, and an oil passage 85 is connected to the input port 101.

  An oil passage 106 is connected to the output port 102, and the oil pressure in the oil passage 106 is input to the feedback port 104. In accordance with the hydraulic pressure of the feedback port 104, a force that biases the spool 97 in a direction opposite to the biasing force of the elastic member 98 is generated. Further, the drain port 103 is connected to the oil pan 84. Furthermore, the signal pressure output from a linear solenoid valve (not shown) is input to the signal pressure port 105. Due to the hydraulic pressure of the signal pressure port 105, a force that biases the spool 97 in the same direction as the elastic member 98 is generated. The oil passage 106 is connected to the primary hydraulic chamber 81 of the actuator 26. The hydraulic pressure in the primary hydraulic chamber 81 is transmitted to a piston (not shown).

  Next, the configuration of the secondary sheave pressure control valve 91 will be described with reference to FIG. The secondary sheave pressure control valve 91 includes a spool 107 that can reciprocate linearly and an elastic member 108 that urges the spool 107 in a predetermined direction. Land portions 109 and 110 are formed on the spool 107. The secondary sheave pressure control valve 91 has an input port 111, an output port 112, a drain port 113, a feedback port 114, and a signal pressure port 115, and an oil passage 89 is connected to the input port 111.

  An oil passage 116 is connected to the output port 112, and the oil pressure in the oil passage 116 is input to the feedback port 114. In accordance with the hydraulic pressure of the feedback port 114, a force that biases the spool 107 in a direction opposite to the biasing force of the elastic member 108 is generated. Further, the drain port 113 is connected to the oil pan 84. Furthermore, the signal pressure output from a linear solenoid valve (not shown) is input to the signal pressure port 115. Due to the hydraulic pressure of the signal pressure port 115, a force that biases the spool 107 in the same direction as the elastic member 108 is generated. The oil passage 116 is connected to the secondary hydraulic chamber 82 of the actuator 27. The hydraulic pressure in the secondary hydraulic chamber 82 is transmitted to a piston (not shown).

  Incidentally, an oil passage 117 that connects the oil passage 106 and the oil passage 116 is provided, and a reversible / variable pump 118 is provided in the oil passage 117. In addition, an electric motor 119 that drives the reversible / variable pump 118 is provided, and a power storage device 120 and an inverter 121 that exchange electric power with the electric motor 119 are also provided. Here, the electric motor 119 may be either one having a function as a driving force source for the vehicle Ve or one not having a function as a driving force source for the vehicle Ve. Furthermore, the electric motor 119 is a power generator / motor provided with a power running function that converts electrical energy into kinetic energy and a regeneration function that converts kinetic energy into electrical energy. As the power storage device 120, either a battery or a capacitor may be used.

  Then, by driving the reversible / variable pump 118 by the electric motor 119, the discharge direction and flow rate of the pressure oil can be controlled. That is, by switching the rotation direction of the reversible / variable pump 118 between forward and reverse, the oil in the oil passage 106 is sucked and discharged to the oil passage 116, and the oil in the oil passage 116 is sucked and discharged to the oil passage 116. The mode to be switched can be selectively switched. Further, the reversible / variable pump 118 can change the amount of oil sucked and discharged between the oil passage 106 and the oil passage 116.

  Next, the operation of the hydraulic circuit 80 shown in FIG. 1 will be described. First, when the engine 1 is operated and the oil pump 83 is driven, pressure oil is supplied to the oil passage 85. The pressure oil supplied to the oil passage 85 is also supplied to the oil passages 89 and 95, and when the oil pressure of the oil passages 85, 89 and 95 is equal to or lower than a predetermined oil pressure, the input port 92 of the line pressure control valve 90 and The drain port 93 is shut off, and the oil pressure in the oil passages 85, 89, 95 increases. When the oil pressure in the oil passages 85, 89, 95 exceeds a predetermined oil pressure, the input port 92 of the line pressure control valve 90 and the drain port 93 are communicated. For this reason, the oil in the oil passages 85, 89, 95 is discharged to the oil pan 84 via the drain port 93, and the increase in the oil pressure in the oil passages 85, 89, 95 is suppressed. When the input port 92 of the line pressure control valve 90 and the drain port 93 are in communication with each other, if the oil pressure in the oil passages 85, 89, 95 drops below a predetermined oil pressure, the oil port 95 through the drain port 93. The flow rate of the pressure oil discharged to the oil is reduced, and the decrease in the oil pressure in the oil passages 85, 89, 95 is suppressed. Thus, the oil pressure of the oil passages 85, 89, 95, that is, the line pressure is regulated by the function of the line pressure control valve 90.

  The pressure oil adjusted in this way is supplied to the input port 101 of the primary sheave pressure control valve 86 and the input port 111 of the secondary sheave pressure control valve 91. First, the hydraulic control of the primary hydraulic chamber 81 of the primary pulley 24 will be described. When the condition for increasing the hydraulic pressure in the primary hydraulic chamber 81 is satisfied, the signal pressure input to the signal pressure port 105 of the primary sheave pressure control valve 86 is increased. Then, due to the urging force corresponding to the hydraulic pressure of the signal pressure port 105, the spool 97 operates upward in FIG. 3, the flow rate of the pressure oil supplied from the oil passage 85 to the oil passage 106 increases, and the drain port 103 Blocked. For this reason, the hydraulic pressure of the pressure oil supplied from the output port 102 of the primary sheave pressure control valve 86 to the primary hydraulic chamber 81 via the oil passage 106 increases.

  On the other hand, when the condition for lowering the hydraulic pressure in the primary hydraulic chamber 81 is satisfied, the signal pressure input to the signal pressure port 105 of the primary sheave pressure control valve 86 is reduced. Then, due to the urging force corresponding to the hydraulic pressure of the feedback port 104, the spool 97 operates downward in FIG. 3, the flow rate of the pressure oil discharged from the oil passage 106 to the drain port 103 increases, and the input port 101 is blocked. Thus, the pressure oil is not supplied from the oil passage 85 to the oil passage 106. In this way, the hydraulic pressure in the primary hydraulic chamber 81 decreases.

  Further, when the condition for maintaining the hydraulic pressure in the primary hydraulic chamber 81 substantially constant is established, the urging force according to the hydraulic pressure of the feedback port 104, the urging force according to the signal pressure of the signal pressure port 105, and the elastic member 98 The signal pressure input to the signal pressure port 105 is controlled so that the spool 97 operates in accordance with the urging force and the input port 101 and the drain port 103 are both shut off.

  Next, hydraulic control of the secondary hydraulic chamber 82 of the secondary pulley 25 will be described. When the condition for increasing the hydraulic pressure in the secondary hydraulic chamber 82 is satisfied, the signal pressure input to the signal pressure port 115 of the secondary sheave pressure control valve 91 is increased. Then, due to the urging force according to the hydraulic pressure of the signal pressure port 115, the spool 107 operates upward in FIG. 4, the flow rate of the pressure oil supplied from the oil passage 89 to the oil passage 116 increases, and the drain port 113 Blocked. For this reason, the hydraulic pressure of the pressure oil supplied from the secondary sheave pressure control valve 91 to the secondary hydraulic chamber 82 via the oil passage 106 is increased.

  On the other hand, when the condition for reducing the hydraulic pressure in the secondary hydraulic chamber 82 is satisfied, the signal pressure input to the signal pressure port 115 of the secondary sheave pressure control valve 91 is reduced. Then, due to the urging force according to the hydraulic pressure of the feedback port 114, the spool 107 operates downward in FIG. 4, the flow rate of the pressure oil discharged from the oil passage 116 to the drain port 113 increases, and the input port 111 is blocked. Thus, the pressure oil is not supplied from the oil passage 89 to the oil passage 116. Therefore, the hydraulic pressure in the secondary hydraulic chamber 82 decreases.

  Further, when the condition for maintaining the hydraulic pressure in the secondary hydraulic chamber 82 to be substantially constant is satisfied, the biasing force according to the hydraulic pressure of the feedback port 114, the biasing force according to the signal pressure of the signal pressure port 115, and the elastic member 108 The signal pressure input to the signal pressure port 115 is controlled so that the spool 107 operates by the correspondence with the urging force and both the input port 111 and the drain port 113 are shut off.

  In the hydraulic circuit 80, the primary sheave pressure control valve 86 controls the hydraulic pressure in the primary hydraulic chamber 81, and the secondary sheave pressure control valve 91 controls the hydraulic pressure in the secondary hydraulic chamber 82 in parallel. By controlling the variable pump 118, it is possible to allow oil to flow back and forth between the primary hydraulic chamber 81 and the secondary hydraulic chamber 82. For example, when the hydraulic pressure in the primary hydraulic chamber 81 is increased to execute rapid acceleration, the reversible / variable pump 118 is driven by the electric motor 119 to pump the oil in the secondary hydraulic chamber 82 via the oil passage 116, The pumped oil can be supplied to the primary hydraulic chamber 81 via the oil passage 106 to perform control to increase the hydraulic pressure in the primary hydraulic chamber 81.

  On the contrary, when the hydraulic pressure of the secondary hydraulic chamber 82 is increased and sudden deceleration is performed, the reversible / variable pump 118 is driven by the electric motor 119 so that the oil in the primary hydraulic chamber 81 passes through the oil passage 106. In addition, the pumped oil can be supplied to the secondary hydraulic chamber 82 via the oil passage 116 to increase the hydraulic pressure in the secondary hydraulic chamber 82. In addition, when it is not necessary to move oil back and forth between the primary hydraulic chamber 81 and the secondary hydraulic chamber 82, for example, when a condition for maintaining the transmission ratio of the belt-type continuously variable transmission 4 substantially constant is established, Alternatively, when all of the pressure oil supplied to the primary hydraulic chamber 81 and the secondary hydraulic chamber 82 is covered by the pressure oil discharged from the oil pump 83, control for stopping the reversible / variable pump 118 is executed.

  Thus, in the first embodiment, the hydraulic pressure of the pressure oil supplied from the oil pump 83 to the primary hydraulic chamber 81 is controlled by the primary sheave pressure control valve 86 and supplied from the oil pump 83 to the secondary hydraulic chamber 82. The oil pressure of the pressure oil is controlled by the secondary sheave pressure control valve 91. Further, the flow rate of the pressure oil supplied to the primary hydraulic chamber 81 and the flow rate of the pressure oil supplied to the secondary hydraulic chamber 82 can be controlled by the reversible / variable pump 118. That is, the hydraulic control and flow rate control of the pressure oil supplied to the primary hydraulic chamber 81 and the secondary hydraulic chamber 82 can be shared by the oil pump 83 and the reversible / variable pump 118. Control accuracy of supply and discharge of pressure oil in the secondary hydraulic chamber 82 is improved.

  For this reason, the primary pulley 24 and the secondary pulley 25 have the minimum necessary without depending on conditions such as variations in the rotational speed of the reversible / variable pump 118 or variations in oil leakage from the primary hydraulic chamber 81 and the secondary hydraulic chamber 82. A clamping pressure can be applied to the belt 28. Here, the minimum necessary clamping pressure means a clamping pressure that can prevent the belt 28 from slipping. Therefore, it is possible to improve the power transmission efficiency between the primary pulley 24 and the secondary pulley 25 and to improve the durability and reliability, and it is possible to secure a stable speed change characteristic.

  As described above, in the first embodiment, when changing the gear ratio of the belt-type continuously variable transmission 4, the oil to be pumped up by the oil pump 83 is executed by executing the control for driving the reversible / variable oil pump 118. It is possible to reduce the amount. Therefore, the capacity of the oil pump 83 can be reduced.

  By the way, in the first embodiment, it is possible to control the supply and discharge of the pressure oil in the primary hydraulic chamber 81 and the secondary hydraulic chamber 82 by either one of the oil pump 83 or the reversible / variable pump 118. An example will be described based on the flowchart of FIG. First, it is determined whether or not the function of either the oil pump 83 or the reversible / variable pump 118 is degraded (step S1).

  For example, if either one of the oil pump 83 or the reversible / variable pump 118 fails and pressure oil cannot be discharged or the discharge hydraulic pressure (discharge oil amount) cannot be controlled, an affirmative determination is made in step S1. The supply and discharge of the pressure oil in the primary hydraulic chamber 81 and the secondary hydraulic chamber 82 are controlled by the normal oil pump (step S2), and the control routine of FIG. On the other hand, if a negative determination is made in step S1, the control routine shown in FIG. 5 is terminated. As described above, even when one of the oil pumps fails, it is possible to control the transmission ratio of the belt-type continuously variable transmission 4 by executing the control example shown in FIG. It can contribute to limp foam running.

  Here, the correspondence between the configuration of the first embodiment and the configuration of the present invention will be described. The oil pump 83 corresponds to the first oil pump of the present invention, and the reversible / variable pump 118 corresponds to the configuration of the present invention. Corresponding to the second oil pump, the primary sheave pressure control valve 86 corresponds to the first pressure control valve of the present invention, and the secondary sheave pressure control valve 91 corresponds to the second pressure control valve of the present invention. . Further, the correspondence between the functional means shown in FIG. 5 and the configuration of the present invention will be described. Step S1 corresponds to the determination means of the present invention, and step S2 corresponds to the oil pump selection means of the present invention. Equivalent to.

  The characteristic configuration shown in the first embodiment is described as follows. That is, the primary pulley and the secondary pulley around which the belt is wound, the primary hydraulic chamber and the secondary hydraulic chamber that control the winding state of the belt in the primary pulley and the secondary pulley, and the primary hydraulic chamber and the secondary hydraulic chamber are pressurized. A first oil pump for supplying oil, a first check valve provided in a path for supplying pressure oil from the first oil pump to the primary hydraulic chamber, and a secondary valve from the first oil pump. A second oil pump that mutually supplies and discharges pressure oil between a second check valve provided in a path for supplying pressure oil to the hydraulic chamber and the primary hydraulic chamber and the secondary hydraulic chamber In the hydraulic control device for a belt-type continuously variable transmission, the pressure oil supplied from the first oil pump to the primary hydraulic chamber A first pressure control valve that controls the hydraulic pressure and a second pressure control valve that controls the hydraulic pressure of the pressure oil supplied from the first oil pump to the secondary hydraulic chamber are provided separately. The first pressure control valve is disposed on the path from the first check valve to the primary hydraulic chamber, and the second pressure control valve is disposed on the path from the second check valve to the secondary hydraulic chamber. This is a hydraulic control device for a belt-type continuously variable transmission.

  It is also possible to replace the judging means described in claim 2 of the claims with a judging device or a judging controller, and the oil pump selecting means with an oil pump selecting device or an oil pump selecting controller. . In this case, the electronic control unit 34 corresponds to a determination device, a determination controller, an oil pump selector, and an oil pump selection controller. Furthermore, the judging means described in claim 2 is read as a judging step, the oil pump selecting means is read as an oil pump selecting step, and the hydraulic control device of the belt-type continuously variable transmission is replaced with the belt-type continuously variable transmission. It can also be read as a hydraulic control method. In this case, step S1 in FIG. 5 corresponds to a determination step, and step S2 corresponds to an oil pump selection step.

  Another configuration example of the hydraulic circuit constituting a part of the hydraulic control device 59 will be described with reference to FIG. The second embodiment corresponds to the third aspect of the present invention. In the configuration of FIG. 6, the same components as those of FIGS. 1, 3, and 4 are denoted by the same reference numerals as those of FIGS.

  The reversible / variable pump 118 has ports 122 and 123, and the ports 122 and 123 are connected to the switching valve 124. The switching valve 124 includes a spool 125 that can operate linearly, an elastic member 126 that biases the spool 125 in a predetermined direction, ports 127, 128, 129, 130, 131, 132, and a signal pressure port 133. Have. The port 127 and the port 122 are connected by the oil passage 134, the port 128 and the oil passage 89 are connected by the oil passage 135, the port 129 and the port 123 are connected by the oil passage 136, and the port 130 and the oil pan are connected. 84 is connected by an oil passage 137, the port 131 and the oil passage 106 are connected by an oil passage 138, and the port 132 and the oil passage 116 are connected by an oil passage 139.

  Further, a switching solenoid valve 140 for inputting a signal pressure to the signal pressure port 133 of the switching valve 124 is provided, and the spool 125 is biased in the direction opposite to the elastic member 126 according to the signal pressure of the signal pressure port 133. Force to do. Here, as the switching solenoid valve 140, it is possible to use a normally closed solenoid valve in which the signal pressure becomes the lowest pressure in a non-energized state. The switching solenoid valve 140 is controlled by the electronic control unit 34.

  Next, the operation of the hydraulic circuit 80 shown in FIG. 6 will be described. In the hydraulic circuit 80 shown in FIG. 6, the same operational effects as those in FIGS. 1, 3, and 4 can be obtained for the same components as those in FIGS. 1, 3, and 4. Incidentally, in the hydraulic circuit 80 shown in FIG. 6, the control of the switching valve 124 can be executed in parallel with the control of the reversible / variable pump 118. Specifically, the spool 125 operates by controlling the signal pressure input to the signal pressure port 133 of the switching valve 124.

  For example, when the first control mode is selected as the control mode of the switching valve 124, the port 127 and the port 128 are communicated, the port 129 and the port 130 are communicated, and the ports 131 and 132 are communicated. Is cut off. As described above, when the first control mode is selected and the reversible / variable pump 118 is driven by the electric motor 119, the oil does not go back and forth between the primary hydraulic chamber 81 and the secondary hydraulic chamber 82. At the same time, the oil in the oil pan 84 is sucked into the port 123 of the reversible / variable pump 118 via the oil passage 137 and the oil passage 136. Then, the pressure oil discharged from the port 122 of the reversible / variable pump 118 to the oil passage 134 passes through the oil passage 135 and the oil passage 89, and the input port 101 of the primary sheave pressure control valve 86 and the secondary sheave pressure control. Supplied to the input port 111 of the valve 91. Then, the pressure oil regulated by the primary sheave pressure control valve 86 is supplied to the primary hydraulic chamber 81, and the pressure oil regulated by the secondary sheave pressure control valve 91 is supplied to the secondary hydraulic chamber 82. .

  On the other hand, when the second control mode is selected as the control mode of the switching valve 124, the port 127 and the port 131 are communicated, the port 129 and the port 132 are communicated, and the port 128 and 130 are blocked. As described above, when the second control mode is selected, the oil passage 138 between the primary hydraulic chamber 81 and the secondary hydraulic chamber 82 is controlled by controlling the rotation direction of the reversible / variable pump 118 by the electric motor 119. , 139 and the switching valve 124, the oil goes back and forth. That is, by supplying the oil in the primary hydraulic chamber 81 to the secondary hydraulic chamber 82 via the oil passages 138 and 134, the reversible / variable pump 118 and the oil passages 136 and 139, the hydraulic pressure in the primary hydraulic chamber 81 is lowered. And control which raises the oil pressure of secondary oil pressure room 82 can be performed. Further, the oil pressure in the primary hydraulic chamber 81 is increased by supplying the oil in the secondary hydraulic chamber 82 to the primary hydraulic chamber 81 via the oil passages 139 and 136, the reversible / variable pump 118, and the oil passages 134 and 138. In addition, it is possible to execute control for reducing the hydraulic pressure in the secondary hydraulic chamber 82.

  Next, the correspondence relationship between the type of driving force source in the vehicle Ve and the control mode of the switching valve 24 will be described. First, the case where the vehicle Ve is a vehicle capable of transmitting the torque of the electric motor 119 to the wheels in addition to the torque of the engine 1, that is, a hybrid vehicle will be described. Here, the wheel to which the torque of the engine 1 is transmitted and the wheel to which the torque of the electric motor 119 is transmitted may be the same or different. In such a hybrid vehicle, when the engine 1 is stopped and the electric motor 119 is driven, the first control mode can be selected. Therefore, even when the engine 1 is stopped, it is possible to independently control the hydraulic pressures of the primary hydraulic chamber 81 and the secondary hydraulic chamber 82 using the discharge pressure of the reversible / variable pump 118 as a source pressure. . In this hybrid vehicle, the second control mode can be selected when both the engine 1 and the electric motor 119 are driven and the speed ratio of the belt type continuously variable transmission 4 is changed.

  Next, the case where the electric motor 119 is a vehicle that does not have a function of transmitting torque to wheels will be described. In such a vehicle, when the ignition switch 58 is turned on and the engine 1 is operated, the engine 1 is stopped when the engine stop condition other than the ignition switch 58 is satisfied, and the engine 1 After the stop, the engine stop condition other than the ignition switch 58 is canceled, and “engine stop / return control” for returning the engine 1 to the operating state can be executed.

  Then, when the engine stop condition is satisfied and the engine 1 is stopped, or when the engine 1 returns to the operating state from the state where the engine stop condition is satisfied and the engine 1 is stopped, the engine rotation The first control mode can be selected when the number is equal to or less than a predetermined number of revolutions. By executing such control, when the engine 1 is returned to the operating state, it is possible to improve the rising response of the hydraulic pressure in the primary hydraulic chamber 81 and the secondary hydraulic chamber 82. In particular, the belt 28 can be prevented from slipping due to an increase in the hydraulic pressure in the secondary hydraulic chamber 82. Furthermore, the first control mode can be selected when the engine 1 is in operation and the condition for maintaining the gear ratio of the belt-type continuously variable transmission 4 is maintained substantially constant. .

  On the other hand, when the engine 1 is operated and the condition for changing the speed ratio of the belt type continuously variable transmission 4 is satisfied, the second control mode can be selected. As described above, also in the second embodiment, the same effect as in the first embodiment can be obtained by driving the reversible / variable pump 118 by the electric motor 119. Although not shown, an oil passage 89 connects between the first check valve 88 and the primary sheave pressure control valve 86, and between the second check valve 96 and the secondary sheave pressure control valve 91, The second embodiment can be applied to a hydraulic circuit having a configuration in which the second check valve 96 is provided in the oil passage 95. Further, the control example of FIG. 5 can be executed also in the hydraulic circuit 80 of the second embodiment.

  Explaining the correspondence between the configuration of the second embodiment and the configuration of the present invention, the oil pan 84 corresponds to the oil holding portion of the present invention, and the switching valve 124, the switching solenoid valve 140, and the oil passages 134, 136. , 137, 138, 139 correspond to the switching device of the present invention, the input port 101 corresponds to the input side of the first pressure control valve of the present invention, and the input port 111 corresponds to the second pressure of the present invention. This corresponds to the input side of the control valve. The correspondence between the other configurations in the second embodiment and the configuration of the present invention is the same as the correspondence between the configuration of the first embodiment and the configuration of the present invention.

  In the third embodiment, a control example that can be executed in the hydraulic circuit 80 of FIG. 1 or the hydraulic circuit 80 of FIG. 6 will be described based on the flowchart shown in FIG. The third embodiment is an embodiment corresponding to claims 4 and 5, in which the primary sheave pressure control valve 86 controls the hydraulic pressure in the primary hydraulic chamber 81 and the secondary sheave pressure control valve 91 controls the secondary hydraulic chamber. In addition to controlling the hydraulic pressure of 82, an example of control executed by the electric motor 119 and the reversible / variable pump 118 when pressure oil is moved back and forth between the primary hydraulic chamber 81 and the secondary hydraulic chamber 82 is provided. Is. Specifically, there are a case where the electric motor 119 is driven as an electric motor and a case where the electric motor 119 is activated as a generator.

  First, the required pressure Pin and the required pressure Pd are calculated based on the target gear ratio of the belt type continuously variable transmission 4 (step S11). Here, the required pressure Pin is the hydraulic pressure in the primary hydraulic chamber 81, and the required pressure Pd is the hydraulic pressure in the secondary hydraulic chamber 82. Next, the required differential pressure ΔP, which is the rate of change of the difference between the required pressure Pin and the required pressure Pd, is calculated (step S12), and according to the calculation result of step S12 between the primary hydraulic chamber 81 and the secondary hydraulic pressure 82. The required torque of the electric motor 119 is calculated so that the oil goes back and forth (step S13). Next, the torque of the electric motor 119 is controlled based on the calculation result of step S13 (step S14), and the control routine of FIG.

  A specific example of the control routine of FIG. 7 will be described based on the diagram of FIG. The diagram of FIG. 8 is a diagram showing the relationship between the hydraulic pressure in the primary hydraulic chamber 81 and the secondary hydraulic chamber 82 and the gear ratio γ of the belt type continuously variable transmission 4. Pin is the hydraulic pressure of the primary hydraulic chamber 81, and Pd is the hydraulic pressure of the secondary hydraulic chamber 82. In FIG. 8, as the gear ratio increases, both the hydraulic pressure in the primary hydraulic chamber 81 and the hydraulic pressure in the secondary hydraulic chamber 82 increase, and as the gear ratio decreases, both the hydraulic pressure in the primary hydraulic chamber 81 and the hydraulic pressure in the secondary hydraulic chamber 82 increase. The hydraulic characteristics when lowered are shown. In FIG. 8, in the range from the minimum gear ratio γmin to the predetermined gear ratio γ1, the oil pressure Pin of the primary hydraulic chamber 81 is controlled to be higher than the oil pressure Pd of the secondary hydraulic chamber 82, and the maximum gear shift from the predetermined gear ratio γ1. In the range of the ratio γmax, the hydraulic pressure Pd of the secondary hydraulic chamber 82 is controlled to be higher than the hydraulic pressure Pin of the primary hydraulic chamber 81. Note that, at the predetermined speed ratio γ1, the hydraulic pressure Pin of the primary hydraulic chamber 81 and the hydraulic pressure Pd of the secondary hydraulic chamber 82 are equal.

First, an example of regenerative control in which the electric motor 119 is activated as a generator when changing the gear ratio of the belt type continuously variable transmission 4 will be described. For example, in the range of the predetermined speed ratio γ1 from the minimum speed ratio gamma] min, when executing the control for gradually increasing the speed ratio (slow deceleration control) is the differential pressure between the primary hydraulic chamber 81 and the secondary hydraulic chamber 82, The pressure oil in the primary hydraulic chamber 81 can be supplied to the secondary hydraulic chamber 82. Here, when the pressure oil in the primary hydraulic chamber 81 flows into the secondary hydraulic chamber 82, the reversible / variable pump 118 is rotated by the kinetic energy of the pressure oil, and the electric motor 119 is activated as a generator. Electric energy generated by the electric motor 119 is charged to the power storage device 120 via the inverter 121.

On the other hand, in the range of the predetermined speed ratio γ1 from the maximum gear ratio .gamma.max, when executing the control for gradually decreasing the speed ratio (slow speed increasing control) is the differential pressure between the primary hydraulic chamber 81 and the secondary hydraulic chamber 82 The pressure oil in the secondary hydraulic chamber 82 can be supplied to the primary hydraulic chamber 81. Here, when the pressure oil in the secondary hydraulic chamber 82 flows into the primary hydraulic chamber 81, the kinetic energy of the pressure oil is converted to a more electric energy to the electric motor 119, the electric energy is charged in the power storage device 120. In this way, the control for converting the kinetic energy of the pressure oil into electric energy by the electric motor 119 is regenerative control. FIG. 8 shows an example in which the speed is gradually increased from the speed ratio γ3 to the speed ratio γ2.

  Next, an example of power running control that drives the electric motor 119 as an electric motor when changing the gear ratio of the belt type continuously variable transmission 4 will be described. First, in the case of executing a control for gradually reducing the speed ratio within the range from the minimum speed ratio γmin to the predetermined speed ratio γ1, the reversible / variable pump 118 is driven by the electric motor 119, and the pressure oil in the secondary hydraulic chamber 82 is supplied. The primary hydraulic chamber 81 can be forcibly supplied. When the hydraulic pressure in the secondary hydraulic chamber 82 and the primary hydraulic chamber 81 are both reduced to reduce the gear ratio of the belt-type continuously variable transmission 4, the pressure oil in the secondary hydraulic chamber 82 is supplied to the primary hydraulic chamber 81. As the hydraulic pressure of the secondary hydraulic chamber 82 decreases, the tension of the belt 28 decreases, and the piston operates by the hydraulic pressure of the primary hydraulic chamber 81 to increase the volume of the primary hydraulic chamber 81. Even when oil is supplied to the primary hydraulic chamber 81, the hydraulic pressure of the primary hydraulic chamber 81 itself decreases.

  On the other hand, in the case of executing the control to increase the transmission ratio gradually within the range of the maximum transmission ratio γmax to the predetermined transmission ratio γ1, the reversible / variable pump 118 is driven by the electric motor 119 and the pressure oil in the primary hydraulic chamber 81 is supplied. The secondary hydraulic chamber 82 can be forcibly supplied. In this way, the control for driving the reversible / variable pump 118 by driving the electric motor 119 with the electric power of the power storage device 120 is the power running control.

  That is, the required torque calculated in step S13 of FIG. 7 is the required torque for regenerative control or the required torque for power running control selected according to the control content of the gear ratio of the belt type continuously variable transmission 4. . Further, in step S <b> 14, regeneration control or power running control is selected as control of the electric motor 119. Thus, in the control example of FIG. 7, when regenerative control is selected, the kinetic energy of the pressure oil can be converted into electrical energy, and the electrical energy can be charged in the power storage device 120.

  By the way, when the speed change condition for changing the speed ratio of the belt-type continuously variable transmission 4 from the current speed ratio to another target speed ratio is satisfied, in particular, the “gradual speed change in which the change ratio of the speed ratio becomes a predetermined value or less. "Is executed, regenerative control is executed in step S14. On the other hand, when executing the shift control in which the gear ratio of the belt-type continuously variable transmission 4 is suddenly increased, or when executing the shift control to rapidly decrease, the regeneration control is prohibited in step S14. Is also possible. As described above, when the regenerative control is prohibited, it is possible to suppress the flow of pressure oil flowing back and forth between the primary hydraulic chamber 81 and the secondary hydraulic chamber 82 from being inhibited, and it is possible to suppress a decrease in shift response. Is possible. Then, as the running state of the vehicle Ve, more specifically, as the shift control of the belt-type continuously variable transmission 4, "shift control where the gear ratio changes gently" or "shift control where the gear ratio changes suddenly" By determining whether or not the regenerative control is permitted or prohibited depending on which one is executed, it is possible to achieve a balance between improvement in the recovery efficiency of electric energy and improvement in shift response.

  Here, the correspondence between the functional means shown in FIG. 7 and the configuration of the present invention will be described. Steps S11 to S14 correspond to the energy recovery means of the present invention, and the belt type continuously variable transmission. The content of the shift control No. 4 corresponds to the “vehicle running state” in the present invention.

  Next, another control example that can be executed in the hydraulic circuit 80 shown in FIG. 6 will be described with reference to FIG. First, when the condition for controlling the transmission ratio of the belt-type continuously variable transmission 4 to be substantially constant is satisfied (step S21), the first control mode is selected as the control mode of the switching valve 124, and the oil pump 83 Among the discharged pressure oil, the excess pressure oil in the oil passages 85, 89, and 95 is returned to the oil passage 137 via the reversible / variable pump 118, and the electric motor 119 is started as a generator to generate electric power. Is recovered (step S22), and this control routine is terminated. That is, the reversible / variable pump 118 is rotated by the kinetic energy when the pressure oil in the oil passages 134 and 135 flows into the oil passages 136 and 137 due to the differential pressure between the oil passages 134 and 135 and the oil passages 136 and 137. In addition, the electric motor 119 is activated as a generator, and the electric energy is charged in the power storage device 120. In addition, when there is no pressure oil for the excess flow rate in the oil passages 85, 89, 95, the control shown in FIG. 5 is not executed.

  Next, an example of control that can be executed by the hydraulic circuit 80 of FIG. 6 will be described based on the flowchart of FIG. The fourth embodiment corresponds to the sixth aspect of the present invention. As described above, the first control mode or the second control mode can be selected as the control mode of the switching valve 124, and the control example of FIG. 10 is based on the work of the reversible / variable pump 118 and the electric motor 119. In this example, the control mode of the switching valve 124 is selected. First, it is determined whether or not the engine 1 is operating (step S31). If the determination in step S31 is affirmative, the work amounts W1 and W2 are calculated (step S32).

  Here, the work amount W1 selects the first control mode as the control mode of the switching valve 124, and the excess pressure oil in the oil passages 85 and 89 is supplied to the oil passages 134 and 135 and the oil passages 136 and 137. The amount of work of the electric motor 119 and the reversible / variable pump 118 when it is assumed that control is performed to discharge to the suction side of the oil pan 84 or the oil pump 83 via the reversible / variable pump 118 due to the pressure difference between It is. Here, regenerative control is executed in the electric motor 119. This work amount W1 can be calculated by the following equation.

  W1 = Ps · Qe−Ps (Qe−QL−Qs) ηm (1)

  On the other hand, the work amount W2 selects the second control mode as the control mode of the switching valve 124, and passes the pressure oil in the primary hydraulic chamber 81 through the reversible / variable pump 118 to the secondary hydraulic chamber 82. This is the work amount of the electric motor 119 and the reversible / variable pump 118 when it is assumed that the control to be supplied to is executed. Here, regenerative control is executed in the electric motor 119. This work amount W2 can be calculated by the following equation.

  W1 = PL · Qe + (Ps−PL) · Qs · ηm (2)

  In the above two formulas, PL is the hydraulic pressure of the oil passages 85 and 89, that is, the line pressure, Ps is the hydraulic pressure of the secondary hydraulic chamber 82, and Qe is the flow rate of the pressure oil discharged from the oil pump 83. QL is the flow rate of pressure oil supplied to the forward / reverse switching device 8 and the torque converter 9, Qs is the flow rate of pressure oil supplied to the secondary hydraulic chamber 82, and ηm is reversible and variable. This is a value obtained by multiplying the efficiency of the pump 118 and the efficiency of the electric motor 119.

  The process of step S32 described above is a process performed assuming that the control mode is selected at a stage before the control mode is actually selected. Following this step S32, it is determined whether or not the work amount W1 exceeds the work amount W2 (step S33). If the determination in step S33 is affirmative, the second work amount W2 corresponding to the smaller work amount W2 is determined. The control mode is selected as the control mode of the switching valve 124 (step S34). Following step S34, the control routine of FIG. 10 is terminated via steps S35 to S38. Here, the process of step S35 is the same as the process of step S11 of FIG. 7, and the process of step S36 is the same as the process of step S12 of FIG. Further, in step S37, in order to convert the kinetic energy of the pressure oil passing through the reversible / variable pump 118 into electric energy, a necessary torque (regenerative torque) for starting the electric motor 119 as a generator is calculated. In S38, regeneration control is executed.

  On the other hand, if a negative determination is made in step S33, the first control mode corresponding to the smaller work amount W1 is selected as the control mode of the switching valve 124 (step S39). Following this step S39, the required line pressure is calculated (step S40), the processing of steps S37 and S38 is executed, and this control routine is terminated. In step S40, the required line pressure is determined by the torque input from the engine 1 to the belt-type continuously variable transmission 4, the hydraulic pressure to be secured in the secondary hydraulic chamber 82 according to the gear ratio of the belt-type continuously variable transmission 4, It is calculated based on the hydraulic pressure of the pressure oil supplied to the switching device 8 and the torque converter 9. If the determination in step S33 is negative and the process proceeds to step S37, the required torque (regenerative torque) for driving the motor 119 as a generator to convert the excess kinetic energy of the pressure oil into electric energy. Torque) is calculated in step S37, and regenerative control is executed in step S38.

  On the other hand, when a negative determination is made in step S31, the oil pump 83 is stopped, so that the reversible / variable pump 118 is driven by the electric motor 119 and the oil in the oil pan 84 is reversible / variable pump. In order to pump up at 118 and supply it to the oil passage 89, control of step S39 and step S40, step S37, and step S38 is performed. Specifically, the necessary torque calculated in step S37 is a necessary torque (power running torque) of the electric motor 119 for securing the necessary line pressure by the pressure oil discharged from the reversible / variable pump 118, and step S38. The power running control is executed at.

  As described above, according to the control example of FIG. 10, the work amount W1 calculated on the assumption that the first control mode is selected as the control mode of the switching valve 124, and the control mode of the switching valve 124, The control mode with the smaller work amount is selected by comparing the work amount W2 calculated on the assumption that the second control mode is selected. Therefore, the efficiency of the electric motor 119 and the reversible / variable pump 118 is improved.

  Here, the correspondence between the functional means shown in FIG. 10 and the configuration of the present invention will be described. Steps S32, S33, S34, and S39 correspond to the control mode selection means of the present invention. Further, the oil pan 84 of the hydraulic circuit 80 shown in FIG. 6 or the suction side of the oil pump 83 corresponds to the low pressure portion of the present invention. The correspondence between the other configuration of the hydraulic circuit 80 shown in FIG. 6 and the configuration of the present invention is the same as that described in the other embodiments.

It is a conceptual diagram which shows Example 1 of the hydraulic circuit used for the hydraulic control apparatus of the belt-type continuously variable transmission in this invention. It is a conceptual diagram which shows the power train and control system of a vehicle which have the hydraulic control apparatus of the belt-type continuously variable transmission of this invention. It is a figure which shows the structural example of the primary sheave pressure control valve shown by FIG. It is a figure which shows the structural example of the secondary sheave pressure control valve shown by FIG. 3 is a flowchart showing an example of control that can be executed by a vehicle having the hydraulic circuit shown in FIG. 1. It is a conceptual diagram which shows Example 2 of the hydraulic circuit used for the hydraulic control apparatus of the belt-type continuously variable transmission in this invention. It is a flowchart which shows the example of control which can be performed with the hydraulic circuit of FIG. 1, and the hydraulic circuit of FIG. FIG. 8 is a diagram corresponding to the control example of FIG. 7, and is a diagram illustrating a relationship between hydraulic pressure and a gear ratio. It is a flowchart which shows the other example of control which can be performed with the vehicle which has a hydraulic circuit shown in FIG. It is a flowchart which shows the other example of control which can be performed with the vehicle which has a hydraulic circuit shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 4 ... Belt type continuously variable transmission, 24 ... Primary pulley, 25 ... Secondary pulley, 28 ... Belt, 59 ... Hydraulic control device, 81 ... Primary hydraulic chamber, 82 ... Secondary hydraulic chamber, 83 ... Oil pump, 84 ... Oil pan 86 ... Primary sheave pressure control valve 87 ... First check valve 91 ... Secondary sheave pressure control valve 96 ... Second check valve 101, 111 ... Input port 118 ... Reversible / variable pump 124 ... switching valve, 140 ... switching solenoid valve, Ve ... vehicle.

Claims (5)

Primary pulley and secondary pulley around which a belt is wound, primary hydraulic chamber and secondary hydraulic chamber for controlling the belt winding state in the primary pulley and the secondary pulley, and pressure oil in the primary hydraulic chamber and the secondary hydraulic chamber A first oil pump to be supplied; a first check valve provided in a path for supplying pressure oil from the first oil pump to the primary hydraulic chamber; and a secondary hydraulic chamber from the first oil pump. A second check valve provided in a path for supplying pressure oil to a second oil pump, and a second oil pump for mutually supplying and discharging pressure oil between the primary hydraulic chamber and the secondary hydraulic chamber In a hydraulic control device for a belt-type continuously variable transmission having:
A first pressure control valve for controlling a hydraulic pressure of pressure oil supplied from the first oil pump to the primary hydraulic chamber; and a hydraulic pressure of pressure oil supplied from the first oil pump to the secondary hydraulic chamber. a second pressure control valve which controls are separately provided Rutotomoni,
An engine for driving the first oil pump;
An electric motor for driving the second oil pump;
When the engine is stopped, the control for mutually supplying and discharging the pressure oil between the primary hydraulic chamber and the secondary hydraulic chamber is stopped, and the oil in the oil holding portion is supplied by the second oil pump. A switching device for sucking and supplying the pressure oil discharged from the second oil pump to the input side of the first pressure control valve and the input side of the second pressure control valve;
Hydraulic control device for a belt type continuously variable transmission which is characterized that you are provided. Determining means for determining whether the function of one of the first oil pump and the second oil pump has deteriorated;
When the function of either one of the oil pumps is reduced, an oil pump selection means for controlling the supply and discharge of the pressure oil in the primary hydraulic chamber and the secondary hydraulic chamber by the function of the normal oil pump is provided. The hydraulic control device for a belt-type continuously variable transmission according to claim 1, wherein: It has energy recovery means for converting the kinetic energy of the pressure oil traveling between the primary hydraulic chamber and the secondary hydraulic chamber into electrical energy based on the running state of the vehicle and recovering the electrical energy . The hydraulic control device for a belt-type continuously variable transmission according to claim 1 or 2, wherein When the speed ratio between the primary pulley and the secondary pulley changes gently, the energy recovery means executes control to recover the electrical energy, while the energy recovery means performs control between the primary pulley and the secondary pulley. The hydraulic control device for a belt-type continuously variable transmission according to claim 3, further comprising a function of prohibiting the control of recovering the electric energy when the gear ratio changes rapidly . Primary pulley and secondary pulley around which a belt is wound, primary hydraulic chamber and secondary hydraulic chamber for controlling the belt winding state in the primary pulley and the secondary pulley, and pressure oil in the primary hydraulic chamber and the secondary hydraulic chamber A first oil pump to be supplied; a first check valve provided in a path for supplying pressure oil from the first oil pump to the primary hydraulic chamber; and a secondary hydraulic chamber from the first oil pump. A second check valve provided in a path for supplying pressure oil to a second oil pump, and a second oil pump for mutually supplying and discharging pressure oil between the primary hydraulic chamber and the secondary hydraulic chamber In a hydraulic control device for a belt-type continuously variable transmission having:
A first pressure control valve for controlling a hydraulic pressure of pressure oil supplied from the first oil pump to the primary hydraulic chamber; and a hydraulic pressure of pressure oil supplied from the first oil pump to the secondary hydraulic chamber. A second pressure control valve to be controlled is provided separately;
A first control mode in which pressure oil in a path from the first oil pump to the first pressure control valve and the second pressure control valve is discharged to a low-pressure portion via the second oil pump; The first control chamber can selectively switch between the first hydraulic chamber and the secondary hydraulic chamber through the second oil pump, and the second control mode for transferring the pressure oil. When the control mode is selected, the work amount of the second oil pump is compared with the work amount of the second oil pump when the second control mode is selected. hydraulic control device for belts CVT, characterized in that it has a control mode selecting means for selecting whichever control mode in which the work of the pump is reduced.

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