JP2011190872A - Control device of continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance drivability at acceleration. <P>SOLUTION: The number of rotations of target input NINT is defined by making a point of fuel consumption when accelerator opening PA is in the second region, while the number of rotations of target input NINT of a continuously variable transmission is defined so as to increase along with vehicle speed V when accelerator opening PA is in the first region. A target drive force is set by a cruise control system with an accelerator pedal unoperated, and the number of rotations of target input NINT is defined by emphasizing fuel consumption when the set target drive force is in the fourth region, while the number of rotations of target input NINT is defined so as to increase along with vehicle speed V when target drive force is in the third region. The number of rotations of an input shaft NIN of the continuously variable transmission is controlled so as to become the set number of rotations of target input NINT. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a control device for a continuously variable transmission, and more particularly to a continuously variable transmission that sets a target rotational speed in accordance with an accelerator opening or a target driving force so that the rotational speed of an input shaft becomes a target rotational speed. It relates to the technology to control.

  A vehicle equipped with a continuously variable transmission is known. The continuously variable transmission can change the gear ratio steplessly. Therefore, the input shaft rotation speed of the continuously variable transmission, that is, the output shaft rotation of a drive source (for example, an engine or an electric motor) connected to the continuously variable transmission, with respect to the vehicle speed, that is, the output shaft rotation speed of the continuously variable transmission. The number can be arbitrarily changed. Therefore, it is possible to adjust the output shaft rotational speed of the drive source so that the fuel consumption is optimum (minimum).

  When the engine speed is controlled to optimize fuel consumption, the vehicle speed may not be proportional to the engine speed. For example, at the time of acceleration, the continuously variable transmission is first downshifted to increase the engine speed to an efficient speed, and then the continuously variable transmission is maintained while maintaining the engine speed substantially constant. The vehicle accelerates while upshifting. Such a phenomenon is called a rubber band feel. In general, the driver expects the engine speed to increase with vehicle speed. Therefore, the continuously variable transmission improves the fuel efficiency, but is accompanied by a phenomenon called a rubber band feel that is contrary to the driver's expectation.

  As one of the measures for improving the drivability of the continuously variable transmission, for example, Japanese Patent Laying-Open No. 2006-51842 (Patent Document 1) is directed to an increase in vehicle speed when a driver's acceleration request is determined. The target rotational speed for acceleration that increases at a predetermined gradient is set, and the speed ratio of the continuously variable transmission and the output torque of the power source are set so that the input shaft rotational speed of the continuously variable transmission becomes the set target rotational speed for acceleration. Disclosed is a vehicle control device including a control means for controlling.

JP 2006-51842 A

  However, since the driver does not operate the accelerator pedal while cruise control for maintaining the vehicle speed constant without operating the accelerator pedal, the driver's acceleration request is not detected. Therefore, only control with an emphasis on fuel efficiency can be executed while cruise control is being executed. In this case, drivability may deteriorate due to the rubber band feel during acceleration.

  The present invention has been made to solve the above-described problem, and an object thereof is to provide a control device for a continuously variable transmission that can improve drivability.

  A control device for a continuously variable transmission according to a first invention is a control device for a continuously variable transmission mounted on a vehicle. The control device includes a means for detecting the accelerator opening, a means for setting the target driving force, and the target rotational speed in the first mode when the accelerator opening is in a predetermined first region. When the accelerator opening is in the second region including the accelerator opening smaller than the accelerator opening included in the first region, the target rotational speed is set in a second mode different from the first mode. If the predetermined third region has the target driving force, the target rotational speed is set in the first mode, and the fourth driving force includes a target driving force smaller than the target driving force included in the third region. A setting means for setting the target rotational speed according to one of the accelerator opening and the target driving force so that the target rotational speed is set in the second mode when the target driving power is in the region; In order to keep the input shaft speed at the set target speed And a control unit for controlling the gear ratio of the speed machine. In the first aspect, the target rotational speed is determined so as to increase as the vehicle speed increases. In the second aspect, the target rotational speed is determined so that the fuel consumption is reduced as compared with the first aspect.

  According to this configuration, when the accelerator opening is small, the target rotational speed is determined with an emphasis on fuel efficiency, while when the accelerator opening is large, that is, when the driver requests acceleration, the vehicle speed The target rotational speed is determined so as to increase with time. The rotational speed of the input shaft of the continuously variable transmission is controlled so as to be the set target rotational speed. Thereby, it is possible to meet the driver's expectation that the rotation speed of the output shaft of the drive source connected to the continuously variable transmission increases with the vehicle speed. When the target driving force is used instead of the accelerator opening, the target rotational speed is determined in the same manner as when the accelerator opening is used. That is, when the target driving force is small, the target rotational speed is determined with an emphasis on fuel consumption, while when the target driving force is large, that is, during acceleration, the target rotational speed is determined so as to increase with the vehicle speed. The rotational speed of the input shaft of the continuously variable transmission is controlled so as to be the set target rotational speed. As a result, even when the target driving force is set without operating the accelerator pedal, for example, during cruise control, the rotational speed of the output shaft of the drive source connected to the continuously variable transmission is set together with the vehicle speed. It can meet the driver's expectation to increase. As a result, a control device for a continuously variable transmission that can improve drivability can be provided.

  In the continuously variable transmission control device according to the second invention, the setting means is determined in the first mode when the accelerator opening is in a fifth region different from the first region and the second region. When the target rotational speed is determined from the target rotational speed and the target rotational speed determined in the second mode, and the target driving force is in the sixth area different from the third area and the fourth area, The target speed is determined according to either the accelerator opening or the target driving force so as to determine the target speed from the target speed determined in the mode and the target speed determined in the second mode. Set the number.

  According to this configuration, in a region between a region where the target rotational speed is determined so as to increase with the vehicle speed and a region where the target rotational speed is determined with emphasis on fuel efficiency, the target rotational speed determined so as to increase with the vehicle speed. The target rotational speed is determined based on both the number and the target rotational speed determined with emphasis on fuel consumption. As a result, when shifting from one of the region where the target rotational speed is determined so as to increase with the vehicle speed and the region where the target rotational speed is determined with emphasis on fuel efficiency, to the other region, the target rotational speed is set. A sudden change in the number can be prevented.

  In the continuously variable transmission control device according to the third aspect of the present invention, in the state where the target rotational speed is determined in the first aspect, the maximum value of the driving force that can be realized with the current gear ratio of the continuously variable transmission is When the driving force is smaller than the driving force, a means for increasing the target rotational speed is further provided.

  According to this configuration, the target driving force can be reliably realized by downshifting.

  In the continuously variable transmission control device according to the fourth aspect of the present invention, in a state where the target rotational speed is determined in the first aspect, a state in which the rotational speed of the input shaft of the continuously variable transmission is higher than a threshold value is predetermined. For further reducing the target rotational speed when the operation continues for more than a predetermined time.

  According to this configuration, when the state where the rotational speed of the input shaft of the continuously variable transmission is high continues, the target rotational speed is reduced. Thereby, the discomfort given to a passenger | crew by the noise etc. from the drive source connected with the continuously variable transmission can be reduced.

  In the continuously variable transmission control apparatus according to the fifth aspect of the invention, the vehicle is mounted with an internal combustion engine coupled to the continuously variable transmission. The control device further includes means for converting the target driving force into a throttle opening. In the state where the target rotational speed is set in the second mode, the setting means is configured to change the amount of change in the throttle opening relative to the amount of change in the target driving force in a region where the amount of change in the throttle opening relative to the amount of change in the target driving force The target rotational speed is set in accordance with the throttle opening converted from the target driving force so that the amount of change in the gear ratio of the continuously variable transmission is smaller than in the region where is small.

  According to this configuration, the target rotational speed is set according to the throttle opening converted from the target driving force. In a region where the amount of change in the throttle opening relative to the amount of change in the target driving force is large, the throttle opening converted from the target driving force changes greatly even when the target driving force changes slightly. Therefore, in the region where the amount of change in the throttle opening relative to the amount of change in the target driving force is large, the amount of change in the gear ratio of the continuously variable transmission is smaller than in the region where the amount of change in the throttle opening relative to the amount of change in the target driving force is small. Is set in accordance with the throttle opening converted from the target driving force. For example, the change amount of the gear ratio is made zero by fixing the gear ratio of the continuously variable transmission to the maximum gear ratio. Thereby, hunting of the gear ratio can be prevented.

  A control device for a continuously variable transmission according to a sixth aspect of the present invention includes means for converting the accelerator opening to a target driving force, a target driving force converted from the accelerator opening, and a set target driving force. Means for controlling a drive source connected to the continuously variable transmission according to any one of them and means for converting the set target driving force into a throttle opening are further provided. The setting means sets the target rotational speed in accordance with one of the detected accelerator opening and the throttle opening converted from the target driving force in a state where the target rotational speed is set in the second mode. To do.

  According to this configuration, while the drive source is controlled according to either the target driving force converted from the accelerator opening or the set target driving force, the detected accelerator opening and target The target rotational speed is set according to any one of the throttle openings converted from the driving force. Thereby, the control of the drive source and the control of the continuously variable transmission can be separated and each can be controlled individually. Therefore, it is possible to prevent the other control from being interrupted by one control. As a result, the continuity of control of the drive source and the continuity of control of the continuously variable transmission can be maintained.

  In the continuously variable transmission control device according to the seventh aspect of the invention, the setting means is configured such that, in a state where the target rotational speed is determined in the second mode, the accelerator opening larger by the load of the auxiliary machine and the load of the auxiliary machine. The target rotational speed is set according to any one of the larger target driving forces.

  According to this configuration, it is possible to take into account the amount of fuel consumed to drive the auxiliary machine when setting the target rotational speed with an emphasis on fuel consumption. Therefore, the target rotational speed at which the fuel efficiency is optimal can be set with higher accuracy.

It is a figure which shows a power train. It is a control block diagram of ECU. It is a functional block diagram of the control system mounted in ECU. It is a figure which shows the 1st area | region and 2nd area | region classified by the accelerator opening (throttle opening). It is a figure which shows the 3rd area | region and 4th area | region classified by the target drive force. It is the figure which compared the boundary line of the lower end of a 1st area | region, and the boundary line of the lower end of a 3rd area | region. It is a figure which shows the target input rotation speed set in linear shift mode. It is a figure which shows a fuel consumption optimal line and an equal power line. It is a figure which shows the map used in order to set target input rotation speed according to throttle opening. It is a figure which shows the area | region where the variation | change_quantity of the throttle opening with respect to the variation | change_quantity of a driving force is large. It is a figure which shows the 1st area | region, the 2nd area | region, and the 5th area | region classified by the accelerator opening (throttle opening). It is a figure which shows the 3rd area | region, 4th area | region, and 6th area | region classified by the target drive force. It is a figure which shows the map used in order to set target input rotation speed according to target drive force. It is a figure which shows the power train of a hybrid vehicle. It is a figure which shows the alignment chart of a power split device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

<First Embodiment>
Referring to FIG. 1, the output torque of engine 200 of power train 100 mounted on a vehicle is input to continuously variable transmission 500 having forward / reverse switching device 400 via torque converter 300. The output of the continuously variable transmission 500 is transmitted to the reduction gear 600 and the differential gear device 700, and is distributed to the left and right drive wheels 800. The power train 100 is controlled by an ECU (Electronic Control Unit) 900 described later. An electric motor may be used as a drive source instead of or in addition to engine 200.

  The torque converter 300 includes a pump impeller 302 connected to the crankshaft of the engine 200 and a turbine runner 306 connected to the forward / reverse switching device 400 via the turbine shaft 304. A lockup clutch 308 is provided between the pump impeller 302 and the turbine runner 306. The lockup clutch 308 is engaged or released when the hydraulic pressure supply to the engagement side oil chamber and the release side oil chamber is switched.

  When the lockup clutch 308 is completely engaged, the pump impeller 302 and the turbine runner 306 are rotated together. The pump impeller 302 is a mechanical oil pump 310 that generates hydraulic pressure for controlling the transmission of the continuously variable transmission 500, generating belt clamping pressure, and supplying hydraulic oil for lubrication to each part. Is provided.

  The forward / reverse switching device 400 is composed of a double pinion type planetary gear device. Turbine shaft 304 of torque converter 300 is connected to sun gear 402. The input shaft 502 of the continuously variable transmission 500 is connected to the carrier 404. Carrier 404 and sun gear 402 are connected via forward clutch 406. Ring gear 408 is fixed to the housing via reverse brake 410. The forward clutch 406 and the reverse brake 410 are frictionally engaged by a hydraulic cylinder. The input rotational speed of the forward clutch 406 is the same as the rotational speed of the turbine shaft 304, that is, the turbine rotational speed NT.

  When the forward clutch 406 is engaged and the reverse brake 410 is released, the forward / reverse switching device 400 enters the forward engagement state. In this state, power in the forward direction is transmitted to the continuously variable transmission 500. When the reverse brake 410 is engaged and the forward clutch 406 is released, the forward / reverse switching device 400 enters the reverse engagement state. In this state, the input shaft 502 is rotated in the reverse direction with respect to the turbine shaft 304. Thereby, the power in the reverse direction is transmitted to the continuously variable transmission 500.

  That is, when the forward clutch 406 or the reverse brake 410 is engaged, the power output from the engine 200 is transmitted to the drive wheels 800. When both forward clutch 406 and reverse brake 410 are released, forward / reverse switching device 400 enters a neutral state in which power transmission is interrupted.

  The forward / reverse switching device 400 may be disposed between the continuously variable transmission 500 and the drive wheel 800.

  The continuously variable transmission 500 is further provided with a primary pulley 504 provided on the input shaft 502, a secondary pulley 508 provided on the output shaft 506, and a metal belt 510 wound around these pulleys. Power is transmitted using frictional forces between the pulleys and the metal belt 510.

  Each pulley is composed of a hydraulic cylinder (sheave) so that the groove width is variable. By controlling the hydraulic pressure of the hydraulic cylinder of the primary pulley 504, that is, the primary sheave, the groove width of each pulley changes. Thereby, the effective diameter of each pulley is changed, and the gear ratio GR (= primary pulley rotation speed NIN / secondary pulley rotation speed NO) is continuously changed. A chain may be used instead of the metal belt 510.

  As shown in FIG. 2, the ECU 900 includes an engine speed sensor 902, a turbine speed sensor 904, a vehicle speed sensor 906, a throttle opening sensor 908, a cooling water temperature sensor 910, an oil temperature sensor 912, an accelerator opening sensor 914, a foot A brake switch 916, a position sensor 918, a primary pulley rotation speed sensor 922, and a secondary pulley rotation speed sensor 924 are connected.

  The engine speed sensor 902 detects the engine speed (engine speed) NE of the engine 200. The turbine rotation speed sensor 904 detects the rotation speed (turbine rotation speed) NT of the turbine shaft 304. The vehicle speed sensor 906 detects the vehicle speed V. A throttle opening sensor 908 detects the opening TA of the electronic throttle valve. Cooling water temperature sensor 910 detects cooling water temperature TW of engine 200. The oil temperature sensor 912 detects the temperature of hydraulic oil (hereinafter also referred to as oil temperature) THO used for the operation of the continuously variable transmission 500. The accelerator opening sensor 914 detects the opening PA of the accelerator pedal. The foot brake switch 916 detects whether or not the foot brake is operated. The position sensor 918 detects the position PSH of the shift lever 920 by determining whether the contact provided at the position corresponding to the shift position is ON or OFF. The primary pulley rotation speed sensor 922 detects the rotation speed (input shaft rotation speed) NIN of the primary pulley 504. Secondary pulley rotational speed sensor 924 detects the rotational speed (output shaft rotational speed) NO of secondary pulley 508. A signal representing the detection result of each sensor is transmitted to ECU 900. The turbine rotational speed NT coincides with the primary pulley rotational speed NIN during forward traveling with the forward clutch 406 engaged. The vehicle speed V is a value corresponding to the secondary pulley rotational speed NO. Therefore, in the present embodiment, the secondary pulley rotational speed NO is used as a physical quantity indicating the vehicle speed V. The vehicle speed V detected by the vehicle speed sensor 906 may be used.

  In the present embodiment, both the accelerator opening PA and the throttle opening TA are expressed as percentages. When the accelerator opening PA and the throttle opening TA are in the fully closed state, the accelerator opening PA and the throttle opening TA are expressed as “0%”. When the accelerator opening PA and the throttle opening TA are fully open, the accelerator opening PA and the throttle opening TA are expressed as “100%”. Since both the accelerator opening PA and the throttle opening TA are expressed as percentages, the accelerator opening PA and the throttle opening TA can be directly compared. That is, the accelerator opening PA and the throttle opening TA are regarded as the same physical quantity.

  ECU 900 includes a CPU (Central Processing Unit), a memory, an input / output interface, and the like. The CPU performs signal processing according to a program stored in the memory. Thereby, output control of the engine 200, shift control of the continuously variable transmission 500, belt clamping pressure control, engagement / release control of the forward clutch 406, engagement / release control of the reverse brake 410, and the like are executed.

  Output control of the engine 200 is performed by an electronic throttle valve 1000, a fuel injection device 1100, an ignition device 1200, and the like. The hydraulic control circuit 2000 performs the shift control of the continuously variable transmission 500, the belt clamping pressure control, the engagement / release control of the forward clutch 406, and the engagement / release control of the reverse brake 410.

  With reference to FIG. 3, the configuration of a vehicle control system implemented in ECU 900 will be described. In FIG. 5, “F” indicates the driving force, “TE” indicates the engine torque, “PA” indicates the accelerator opening, “TA” indicates the throttle opening, and “NO” indicates the secondary pulley rotation speed. The unit of driving force is “N (Newton)”. The functions of each configuration described below may be realized by hardware, may be realized by software (program), or may be realized by a combination of hardware and software. May be.

  The control system includes a power train driver model 3000, a cruise control system 3010 and a power train manager 3100, an engine control system 3200, and a hydraulic control system 3300.

  The power train driver model 3000 is a model (function) used for setting the target driving force of the vehicle based on the driver's operation. In the present embodiment, a target driving force is set by driving force setting unit 3002 from accelerator opening PA and vehicle speed V (secondary pulley rotational speed NO) according to a map determined in advance based on the results of experiments and simulations. Is done.

  The cruise control system 3010 automatically sets the target driving force according to the behavior of the vehicle. For example, the cruise control system 3010 automatically sets a target driving force necessary for maintaining the vehicle speed V set by the driver based on a map created in advance by the designer.

  In addition, control systems such as VSC (Vehicle Stability Control), TRC (TRaction Control), ABS (Antilock Brake System), EPS (Electric Power Steering), etc. for stabilizing the behavior of the vehicle may be installed. . VSC is a control that ensures the stability of the vehicle by automatically setting optimum values such as the brake hydraulic pressure of each wheel and the target driving force of the vehicle when the sensor detects that the front and rear wheels are likely to skid. is there. TRC automatically sets optimal values such as brake hydraulic pressure of each wheel and target driving force of the vehicle when the sensor detects idling of the driving wheel when starting and accelerating on a slippery road surface. It is the control to ensure. ABS is a control system that automatically sets an optimum value of brake hydraulic pressure and prevents wheel lock. EPS is a control system that assists steering of a steering wheel by the force of an electric motor.

  The power train manager 3100 includes a driving force arbitration unit 3102 that adjusts a target driving force input from the power train driver model 3000 and the cruise control system 3010. For example, the target driving force input from the power train driver model 3000 and the cruise control system 3010 is adjusted so as to select the largest target driving force. Note that the method for adjusting the target driving force may be changed according to the driving state of the vehicle. The smallest target driving force may be selected.

  The target driving force adjusted by the driving force adjusting unit 3102 is converted into the target engine torque by the torque converting unit 3104. For example, the target driving force is converted into the target engine torque by dividing the product of the target driving force and the wheel radius by the current gear ratio of the continuously variable transmission 500 or the like. Since a known general technique may be used as a method for converting driving force into torque, detailed description thereof will not be repeated here.

  The target engine torque converted from the target driving force in the torque converter 3104 is input to the engine control system 3200. The engine control system 3200 controls the output torque of the engine 200 such as the electronic throttle valve 1000, ignition timing, and EGR (Exhaust Gas Recirculation) valve so as to realize the target engine torque input from the power train manager 3100. A device (actuator) provided in the engine 200 is controlled.

  Engine 200 is controlled so as to output torque that realizes power necessary for driving auxiliary machines (such as an alternator, a water pump, and an oil pump) of engine 200 in addition to target engine torque. The unit of power is “W (Watt)”.

  In addition to the target engine torque, the power train manager 3100 has a function of setting a target input speed NINT of the continuously variable transmission 500, that is, a target speed of the primary pulley speed NIN.

  The target input rotational speed NINT depends on one of the accelerator opening PA detected by the accelerator opening sensor 914 and the throttle opening TA converted from the target driving force set by the cruise control system 3010. Is set.

  The target driving force set by the cruise control system 3010 is converted into the throttle opening degree TA by the throttle conversion unit 3110. The target driving force set by the cruise control system 3010 is converted into the throttle opening degree TA, for example, according to a map created by the developer according to the results of experiments and simulations. The method for converting the target driving force into the throttle opening degree TA is not limited to this.

  The throttle opening degree PA detected by the accelerator opening degree sensor 914 and the throttle opening degree TA converted from the target driving force set by the cruise control system 3010 are adjusted by the throttle adjusting unit 3112. In the processing after the throttle adjusting unit 3112, the accelerator opening PA is handled as the throttle opening TA. The throttle adjuster 3112 selects, for example, the largest throttle opening degree TA. Note that the arbitration method of the throttle opening degree TA may be changed according to the driving state of the vehicle. The smallest throttle opening TA may be selected. Further, the throttle opening TA converted from the target driving force set according to the accelerator opening PA and the throttle opening TA converted from the target driving force set by the cruise control system 3010 are adjusted. May be.

  The throttle opening degree TA selected by the throttle adjusting unit 3112 is input to the target input rotation speed setting unit 3114. Target input rotation speed setting unit 3114 sets target input rotation speed NINT according to a map having throttle opening degree TA and vehicle speed V as parameters. The throttle opening TA input to the target input rotation speed setting unit 3114 is the same as the accelerator opening PA, or is converted from the target driving force. Therefore, the target input rotation speed setting unit 3114 sets the target input rotation speed NINT according to one of the accelerator opening PA and the target driving force.

  When the throttle adjuster 3112 selects the accelerator opening PA (throttle opening TA) detected by the accelerator opening sensor 914, the target input rotational speed NINT is determined according to the map shown in FIG. Depending on the throttle opening (TA) and the vehicle speed V, it is set in the linear shift mode or the optimum fuel consumption mode.

  As shown in FIG. 4, when the accelerator opening PA is in the first region including the large accelerator opening PA (throttle opening TA), the target input rotational speed NINT is set in the linear shift mode. When the accelerator opening PA is in the second area including the accelerator opening PA smaller than the accelerator opening PA included in the first area, the target input rotational speed NINT is set in the fuel efficiency optimal mode different from the linear shift mode. The

  In the linear shift mode, the target input rotational speed NINT is determined so as to increase as the vehicle speed V increases. In the fuel efficiency optimum mode, the target input rotational speed NINT is determined so that the fuel consumption is reduced as compared with the linear shift mode. The linear shift mode and the fuel efficiency optimal mode will be described in more detail later.

  Similarly, when the throttle opening degree TA converted from the target driving force set by the cruise control system 3010 is selected by the throttle adjuster 3112, the target input rotational speed NINT is determined according to the map shown in FIG. The linear shift mode or the optimum fuel consumption mode is set according to the throttle opening degree TA and the vehicle speed V converted from the force. In the map shown in FIG. 5, the target driving force before being converted to the throttle opening degree TA is shown instead of the throttle opening degree TA for the sake of explanation.

  As shown in FIG. 5, when the target driving force is in the third region including the large target driving force (throttle opening TA), the target input rotational speed NINT is set in the linear shift mode. When the target driving force is present in the fourth region including the target driving force smaller than the target driving force included in the third region, the target input rotational speed NINT is set in the fuel efficiency optimal mode.

  The target input rotation speed setting unit 3114 receives either the throttle opening TA that is the same as the accelerator opening PA or the throttle opening TA converted from the target driving force. As a result, the target input rotational speed setting unit 3114 is one of the case where the accelerator opening PA is in the first area shown in FIG. 4 and the case where the target driving force is in the third area shown in FIG. In one case, the target input rotational speed NINT is set in the linear shift mode.

  In this embodiment, the accelerator opening PA (throttle opening TA) sets the target input speed NINT in the linear shift mode rather than the target driving force (throttle opening TA converted from the target driving force). Therefore, various threshold values are set so as to easily satisfy the conditions.

  For example, as shown in FIG. 6, the boundary line that defines the lower end of the first region is determined to be lower than the boundary line that defines the lower end of the third region, which is indicated by a broken line. In FIG. 6, a line obtained by converting the boundary line defining the lower end of the third region shown in FIG. 5 into the throttle opening degree TA is indicated by a broken line.

  Thereby, when the driver operates the accelerator pedal, it is possible to more easily realize the control corresponding to the operation of the driver.

  As shown in FIG. 7, in the linear shift mode, the target input rotational speed NINT is set so that the vehicle speed V is proportional to the target input rotational speed NINT. More specifically, for example, when the accelerator opening PA (throttle opening TA) or the target driving force (throttle opening TA converted from the target driving force) is stable, the gear of the continuously variable transmission 500 is used. The ratio is fixed. The target input rotational speed NINT may be increased in proportion to the vehicle speed, while the gear ratio of the continuously variable transmission 500 may be reduced (so that the continuously variable transmission 500 is upshifted).

  When setting the target input speed NINT in the linear shift mode, the engine speed NE is increased in proportion to the vehicle speed in consideration of the speed ratio of the torque converter 300 (output shaft speed / input shaft speed). A target input rotational speed NINT is set.

  Returning to FIG. 3, the target input rotational speed NINT set in the linear shift mode is corrected by the first correction unit 3121 and the second correction unit 3122 according to the driving state of the vehicle.

  The first correction unit 3121 cannot realize the target driving force selected by the driving force arbitration unit 3102 even if the output power of the engine 200 is increased in a state where the target input rotational speed NINT is determined in the linear shift mode (realization). The target input speed NINT is increased.

  For example, if the product of the maximum value of the driving force obtained by the current gear ratio of continuously variable transmission 500 and a predetermined constant K is smaller than the target driving force selected by driving force arbitration unit 3102, The input rotational speed NINT is increased. Similarly, when the accelerator opening PA increases rapidly, the target input rotation speed NINT is increased. For example, when the rate of change of accelerator pedal position PA is equal to or greater than a threshold value and accelerator pedal position PA is equal to or greater than the threshold value, target input rotation speed NINT is increased.

  The target input rotational speed NINT is increased to a rotational speed at which the target driving force selected by the driving force arbitration unit 3102 can be realized. Thereby, continuously variable transmission 500 can be downshifted. Therefore, a necessary driving force can be ensured.

  In the present embodiment, a constant K and various threshold values are set so that the accelerator opening PA is more easily satisfied than the target driving force in order to correct the target input rotational speed NINT to increase. The

  Note that by setting the constant K to be greater than 1, priority can be given to lowering the rotation speed of the primary pulley rotation speed NIN than to realizing the driving force. In this case, it is preferable to notify the power train driver model 3000 or the cruise control system 3010 that the accuracy of the driving force to be realized has deteriorated by using a signal or the like, and to interrupt the feedback control and the integral calculation.

  When the target input rotational speed NINT is determined in the linear shift mode, the second correction unit 3122 has a state where the primary pulley rotational speed NIN of the continuously variable transmission 500 is higher than a threshold value for a predetermined time or longer. The target input rotational speed NINT is reduced. Thereby, the discomfort given to a driver by the sound which engine 200 emits can be relieved.

  When the target input rotation speed NINT is corrected by the first correction unit 3121 or the second correction unit 3122, it is preferable to limit the rate of change of the target input rotation speed NINT. By limiting the rate of change of the target input rotational speed NINT, a sudden change in the primary pulley rotational speed NIN can be prevented.

  In the fuel efficiency optimal mode, the rotational speed at which the fuel efficiency is optimal, which is determined from the target driving force and the fuel consumption map, is set as the target input rotational speed NINT. The target input rotational speed NINT may be defined by a static shift line considering fuel consumption and the like.

  In short, the target input speed NINT set in the fuel efficiency optimal mode is the speed at which the fuel consumption is the smallest among the operating points of the engine that can achieve the target driving force selected as a result of the arbitration at the current vehicle speed V. is there. Specifically, as shown in FIG. 8, the rotational speed at the intersection of the optimum fuel consumption line and the equal power line defined by the developer according to the results of experiments and simulations is set as the target input rotational speed NINT. .

  Instead of sequentially calculating the target rotational speed NINT from the intersection of the optimal fuel consumption line and the equal power line, in this embodiment, the rotational speed at the intersection of the optimal fuel consumption line and the equal power line is defined as the target input rotational speed NINT. Map is used.

  As shown in FIG. 9, the target input rotational speed NINT is set according to a map having the throttle opening degree TA and the vehicle speed V as parameters. The arrows in FIG. 9 indicate that a larger target input rotational speed NINT is set as the throttle opening degree TA (accelerator opening degree PA) is larger.

  The map used for setting the target input rotational speed NINT is created in advance by the developer based on the results of experiments and simulations, for example. The target input speed NINT is set in consideration of the requirement that the target input speed NINT is uniquely determined by the vehicle speed V and the target driving force in addition to the requirement that the fuel consumption is optimized by using the map. Can do.

  In the fuel efficiency optimum mode, the gear of the continuously variable transmission 500 is larger in the region where the amount of change in the throttle opening relative to the amount of change in the target driving force is larger than in the region where the amount of change in throttle opening relative to the amount of change in the target driving force is small. The target input rotation speed NINT is set so that the amount of change in the ratio is small.

  Specifically, when throttle opening degree TA (acceleration opening degree PA) and vehicle speed V are within the region surrounded by the broken line in FIG. 10, the gear ratio of continuously variable transmission 500 is fixed to the upper limit value. In addition, a target input rotational speed NINT is determined. For example, when the throttle opening degree TA (accelerator opening degree PA) and the vehicle speed V are within the region surrounded by the broken line in FIG. 10, the target input speed NINT equal to or higher than the upper limit speed shown in FIG. 9 is set. In addition, the gear ratio of the continuously variable transmission 500 is fixed to the upper limit value by limiting the target input rotation speed NINT with the upper limit rotation speed. Thereby, hunting of the target input rotation speed NINT can be prevented.

  Returning to FIG. 3, when the target input rotational speed NINT is determined in the fuel efficiency optimal mode, the throttle opening corresponding to the load of the auxiliary machine is added to the throttle opening TA (accelerator opening PA) selected by the throttle adjuster 3112. The target input rotational speed NINT is set using the throttle opening degree TA to which TA is added. That is, in the fuel efficiency optimal mode, the target input rotation speed NINT is set according to either the accelerator pedal opening PA that is larger by the load of the auxiliary device of the engine 200 or the target driving force that is larger by the load of the auxiliary device. .

  The throttle opening degree TA corresponding to the load of the auxiliary machine is converted from the power necessary for driving the auxiliary machine by the throttle conversion unit 3116. For example, according to a map created in advance by a developer based on experiments and simulations, the power required to drive the auxiliary machine is converted into the throttle opening TA. In addition, since the method of calculating the load of the auxiliary machine of the engine 200 (power required for driving the auxiliary machine) should just use a known general technique, the detailed description is not repeated here.

  The target input rotational speed NINT set by the power train manager 3100 is input to the hydraulic control system 3300. The hydraulic control system 3300 controls the gear ratio of the continuously variable transmission 500 using the hydraulic control circuit 2000 so that the actual primary pulley rotational speed NIN becomes the target input rotational speed NINT set by the power train manager 3100. To do.

  As described above, according to the present embodiment, when the accelerator opening PA is small, the target input rotational speed NINT is determined with emphasis on fuel efficiency, while when the accelerator opening PA is large, that is, the driver Is required to accelerate, the target input rotational speed NINT is determined so as to increase with the vehicle speed V. The input shaft rotational speed (primary pulley rotational speed) NIN of the continuously variable transmission 500 is controlled so as to become the set target input rotational speed NINT. Thus, the driver's expectation that the rotational speed NE of the engine 200 connected to the continuously variable transmission 500 increases with the vehicle speed V can be met. When the target driving force is used instead of the accelerator opening PA by the cruise control system 3010, the target input rotational speed NINT is determined in the same manner as when the accelerator opening PA is used. In other words, when the target driving force is small, the target input rotational speed NINT is determined with an emphasis on fuel efficiency, while when the target driving force is large, that is, during acceleration, the target input rotational speed increases with the vehicle speed V. NINT is defined. The input shaft rotational speed NIN of the continuously variable transmission 500 is controlled so as to become the set target input rotational speed NINT. Thus, even when the target driving force is set without operating the accelerator pedal, the driver's expectation that the engine speed NE increases with the vehicle speed V can be met. As a result, drivability can be improved.

<Second Embodiment>
Hereinafter, a second embodiment will be described. As shown in FIG. 11, in the present embodiment, the first region where the target input rotational speed NINT is set in the linear shift mode and the second region where the target input rotational speed NINT is set in the fuel efficiency optimal mode. Are separated from each other.

  The throttle adjuster 3112 selects the accelerator opening PA (throttle opening TA) detected by the accelerator opening sensor 914, and sets the accelerator opening in a fifth area different from the first area and the second area. When there is a PA, the target input speed NINT is determined from the target input speed NINT determined in the linear shift mode and the target input speed NINT determined in the fuel efficiency optimal mode, depending on the accelerator opening PA. A target input rotational speed NINT is determined.

  Similarly, as shown in FIG. 12, the third area where the target input speed NINT is set in the linear shift mode and the fourth area where the target input speed NINT is set in the fuel efficiency optimal mode are separated from each other. ing.

  A throttle opening degree TA converted from the target driving force set by the cruise control system 3010 is selected by the throttle adjusting unit 3112, and the target driving force is applied to a sixth region different from the third region and the fourth region. When there is (throttle opening TA), the target drive is performed so that the target input speed NINT is determined from the target input speed NINT determined in the linear shift mode and the target input speed NINT determined in the fuel efficiency optimum mode. The target input rotational speed NINT is set according to the force.

  Other structures are the same as those in the first embodiment. Therefore, detailed description thereof will not be repeated here.

  Hereinafter, a method for setting the target input rotation speed NINT will be described in more detail. The target input rotation speed NINT is calculated based on the following equation.

NINT = NINT ₁ × α + NINT ₂ × (1−α) (1)
In Expression 1, “NINT ₁ ” indicates the target input rotational speed NINT set in the linear shift mode. “NINT ₂ ” indicates a target input rotational speed NINT set in the fuel efficiency optimal mode. “Α” is a coefficient from 0 to 1, and indicates the degree of contribution of the linear shift mode to the target input rotational speed NINT.

In the present embodiment, the target input rotation speed NINT ₁ set in the linear shift mode and the target input rotation speed NINT ₂ set in the fuel efficiency optimal mode are always calculated. “Α” is “1” in the first region and the third region described above, “0” in the second region and the fourth region described above, and the fifth region and the sixth region described above. In this area, the value is defined to be larger than “0” and smaller than “1”.

  In this case, the accelerator is moved from one region to the other region in the region where the target input rotational speed NINT is set in the linear shift mode and the region where the target input rotational speed NINT is set in the fuel efficiency optimal mode. When the opening degree PA or the target driving force shifts, the target input rotation speed NINT can be changed gently.

  Instead of using Equation 1, a process in which the target input rotational speed NINT changes by a predetermined change amount may be executed.

<Third Embodiment>
In the first and second embodiments, as shown in FIG. 13, the target input rotational speed NINT may be set using a target driving force instead of the accelerator opening PA and the throttle opening TA. In this case, if the accelerator opening PA and the throttle opening TA used as the parameters of the maps described in the first embodiment and the second embodiment are converted into the target driving force and used. Good.

  In the present embodiment, when the target input rotational speed NINT is determined in the fuel efficiency optimal mode, the target input rotational speed NINT is set using the target driving force applied with the driving force corresponding to the load of the auxiliary machine. The driving force corresponding to the load of the auxiliary machine is converted from the power necessary for driving the auxiliary machine by the driving force converting unit 3118.

<Fourth embodiment>
In the first to third embodiments, as shown in FIG. 14, a hybrid vehicle in which a first motor generator 201 and a second motor generator 202 are mounted in addition to the engine 200 may be used. The hybrid vehicle travels by driving force from at least one of engine 200 and second motor generator 202.

  Engine 200, first motor generator 201, and second motor generator 202 are connected via power split mechanism 204. Torque generated by the engine 200 is divided into two paths by the power split mechanism 204. One path transmits torque to the continuously variable transmission 500. The other path transmits torque to the first motor generator 201.

  First motor generator 201 is a three-phase AC rotating electric machine. First motor generator 201 is driven by the torque of engine 200 divided by power split mechanism 204 to generate power. The electric power generated by the first motor generator 201 is selectively used according to the running state of the vehicle and the state of the remaining capacity of a battery (not shown). For example, during normal traveling, the electric power generated by the first motor generator 201 becomes the electric power for driving the second motor generator 202 as it is. On the other hand, when the remaining capacity of the battery is lower than a predetermined value, the electric power generated by first motor generator 201 is stored in the battery.

  Second motor generator 202 is a three-phase AC rotating electric machine. Second motor generator 202 is driven by at least one of the electric power stored in the battery and the electric power generated by first motor generator 201.

  The output torque of the second motor generator 202 is input to the continuously variable transmission 500. As a result, the second motor generator 202 assists the engine 200 or causes the vehicle to travel by the driving force from the second motor generator 202.

  During regenerative braking of the plug-in vehicle, the second motor generator 202 is driven as a generator. Thus, second motor generator 202 operates as a regenerative brake that converts braking energy into electric power. The electric power generated by the second motor generator 202 is stored in a battery.

  Power split device 204 is composed of a planetary gear including a sun gear, a pinion gear, a carrier, and a ring gear. The pinion gear engages with the sun gear and the ring gear. The carrier supports the pinion gear so that it can rotate. The sun gear is connected to the rotation shaft of the first motor generator 201. The carrier is coupled to the crankshaft of engine 200. The ring gear is connected to the rotation shaft of second motor generator 202 and the input shaft of continuously variable transmission 500.

  The engine 200, the first motor generator 201, and the second motor generator 202 are connected via a power split mechanism 204 formed of a planetary gear, so that the engine 200, the first motor generator 201, and the first motor generator 201 and the first motor generator 201 are connected as shown in FIG. The number of rotations of the two-motor generator 202 is connected by a straight line in the nomograph. Therefore, engine speed NE is determined by the influence of the input speed NIN of continuously variable transmission 500 and the speed of first motor generator 201.

  In such a hybrid vehicle, when setting the target input rotational speed NINT in the linear shift mode, the engine rotational speed NE is made proportional to the vehicle speed V, and the balance of electric power by the first motor generator and the second motor generator is set. It is preferable to set the target input rotational speed NINT so as to be optimal.

<Other embodiments>
In the first to fourth embodiments, instead of controlling the power train 100 using the driving force of the vehicle, the power train 100 may be controlled using the power of the vehicle. That is, the target power may be set instead of the target driving force. However, since the torque is obtained by dividing the power by the output shaft rotational speed NO of the continuously variable transmission 500, that is, the vehicle speed, and the driving force is obtained by dividing the torque by the radius of the wheel, the target power and the target It can be regarded as synonymous with driving force. That is, the target power is considered to be a kind of target driving force.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  100 power train, 200 engine, 201 first motor generator, 202 second motor generator, 204 power split mechanism, 300 torque converter, 400 forward / reverse switching device, 500 continuously variable transmission, 502 input shaft, 504 primary pulley, 506 output Shaft, 508 Secondary pulley, 510 Metal belt, 600 Reduction gear, 700 Differential gear device, 800 Driving wheel, 914 Accelerator opening sensor, 3000 Powertrain driver model, 3002 Driving force setting unit, 3010 Cruise control system, 3100 Powertrain Manager, 3102 Driving force adjuster, 3104 Torque converter, 3110 Throttle converter, 3112 Throttle adjuster, 3114 Target input speed setting unit, 3116 Throttle change Department, 3118 driving force converting unit, 3121 first correction unit, 3122 second corrector, 3200 engine control system, 3300 hydraulic control system.

Claims (7)

A control device for a continuously variable transmission mounted on a vehicle,
Means for detecting the accelerator opening;
Means for setting a target driving force;
When the accelerator opening is in the predetermined first area, the target rotational speed is set in the first mode, and the second area includes an accelerator opening smaller than the accelerator opening included in the first area. When there is an accelerator opening, the target rotational speed is set in a second mode different from the first mode, and when there is a target driving force in a predetermined third region, the first mode is set. A target rotational speed is set, and when there is a target driving force in a fourth region including a target driving force that is smaller than the target driving force included in the third region, the target rotational speed is set in the second mode. And setting means for setting the target rotational speed according to any one of the accelerator opening and the target driving force;
Control means for controlling the gear ratio of the continuously variable transmission so that the rotational speed of the input shaft becomes a set target rotational speed,
In the first aspect, the target rotational speed is determined so as to increase as the vehicle speed increases,
In the second aspect, the control device for the continuously variable transmission, in which the target rotational speed is determined so that the fuel consumption is reduced as compared with the first aspect.   When the accelerator opening is in a fifth area different from the first area and the second area, the setting means has a target rotational speed determined in the first aspect, and the second aspect. When the target rotational speed is determined from the target rotational speed determined in (5) and there is a target driving force in a sixth area different from the third area and the fourth area, the target rotational speed is determined in the first mode. Setting the target rotational speed in accordance with either the accelerator opening or the target driving force so as to determine the target rotational speed from the target rotational speed and the target rotational speed determined in the second mode; The continuously variable transmission control device according to claim 1.   In a state where the target rotational speed is determined in the first aspect, if the maximum value of the driving force that can be realized with the current gear ratio of the continuously variable transmission is smaller than the target driving force, the target rotational speed is increased. The continuously variable transmission control device according to claim 1, further comprising:   In the state where the target rotational speed is determined in the first aspect, when the rotational speed of the input shaft of the continuously variable transmission is higher than the threshold value for a predetermined time or longer, the target rotational speed is decreased. The continuously variable transmission control device according to claim 1, further comprising: The vehicle is equipped with an internal combustion engine coupled to the continuously variable transmission,
A means for converting the target driving force into a throttle opening;
In the state where the target rotational speed is set in the second mode, the setting means has a throttle opening degree with respect to the target driving force change amount in a region where the throttle opening change amount with respect to the target driving force change amount is large. The target rotational speed is set according to the throttle opening converted from the target driving force so that the amount of change in the gear ratio of the continuously variable transmission is smaller than in a region where the amount of change is small. Control device for continuously variable transmission. Means for converting the accelerator opening to the target driving force;
Means for controlling a drive source connected to the continuously variable transmission according to any one of a target drive force converted from an accelerator opening and a set target drive force;
Means for converting the set target driving force into a throttle opening,
In the state where the target rotational speed is set in the second mode, the setting means sets the target rotational speed according to either the detected accelerator opening or the throttle opening converted from the target driving force. The continuously variable transmission control device according to claim 1, wherein:   In the state where the target rotational speed is determined in the second mode, the setting means responds to either one of the accelerator opening degree that is larger by the load of the auxiliary machine and the target driving force that is larger by the load of the auxiliary machine. 2. The continuously variable transmission control device according to claim 1, wherein the target rotational speed is set.

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