JP2006200589A - Variable speed control device for vehicular continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable speed control device for a continuously variable transmission for avoiding a sense of incongruity during shifting not intended by a driver without impairing normal shifting responsiveness. <P>SOLUTION: The variable speed control device for the vehicular continuously variable transmission executes the control of an actuator to change a speed ratio with feedback control based on a deviation between a target value and an actual value and feedforward control based on the target value or another target value. It comprises a variable speed restricting means (S0083) for restricting a speed controlled variable with the feedforward control when executing the shifting not intended by the driver. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a control device for controlling a gear ratio of a continuously variable transmission capable of continuously changing a gear ratio, and in particular, a gear shift configured to execute the gear shift control by feedback control and feedforward control. The present invention relates to a control device.

  Since a continuously variable transmission for a vehicle can continuously change the gear ratio, the target input is based on the vehicle state such as the vehicle speed, the engine speed, and the required amount of driving represented by the amount of depression of the accelerator pedal. A target value such as a rotational speed or a target speed ratio is obtained, and the speed ratio is controlled so that an actual input speed or an actual value such as an actual speed ratio matches the target value. Such speed ratio control is normally executed by feedback control based on the deviation between the target value and the actual value. Since the feedback control is a control for obtaining a control amount by multiplying the deviation by a predetermined gain, it is executed when the deviation occurs and is premised on the occurrence of the deviation, so there is an inevitable control delay. Increasing the gain to correct this causes inconveniences such as hunting or poor convergence. Therefore, conventionally, feed-forward control is used together. Examples thereof are described in Patent Document 1 and Patent Document 2.

  Since the feedforward control is a control for calculating the control amount based on the target value, the control can be executed without waiting for the detection of the deviation, and is superior to the feedback control in terms of responsiveness. Therefore, the invention described in Patent Document 1 is configured to perform shift control by using both feedback control and feedforward control in combination.

On the other hand, since the control characteristics of feedback control and feedforward control are different as described above, the invention described in Patent Document 2 weights feedback control and feedforward control, and learns a physical model. Previously, feed-forward control is prohibited.
JP 2001-248726 A JP 2003-301935 A

  The gear ratio of the continuously variable transmission mounted on the vehicle is controlled so as to satisfy both the drive request amount and the reduction in fuel consumption, and therefore when the drive request amount increases due to depression of the accelerator pedal, etc. Is controlled to increase the speed ratio and to decrease the speed ratio when the vehicle speed increases. Such shift control is executed so that the responsiveness is improved as much as possible within a range in which a shock due to a sudden change in driving torque does not cause a sense of incongruity. However, the shift control in the continuously variable transmission is not performed only based on the operation of the accelerator pedal by the driver, but is performed according to the vehicle situation, that is, without the driver's intention. There is also. For example, when applying a so-called engine brake that uses a load generated by forcibly rotating a power source such as an engine with an inertial force of a vehicle as a braking force, the gear ratio is increased by detecting a coast state. A downshift is performed. When the internal combustion engine (engine) is warmed up, the gear ratio is set so that the gear ratio is increased in order to increase the rotational speed of the internal combustion engine.

  If the control during these shifts not based on the driver's intention is controlled by both the feedback control and the feedforward control as described above, the shift response is usually normal. The change in the driving torque and the change in the number of revolutions of the power source accompanying the speed change occur in a state where the driver intends or does not expect the speed change to occur. For passengers, it can be experienced as a sudden change, which can cause discomfort.

  The present invention has been made paying attention to the above technical problem, and provides a speed change control device capable of preventing a sense of incongruity caused by speed change not intended by the driver without impairing speed change response. It is intended.

  In order to achieve the above object, according to the first aspect of the present invention, the control of the actuator for changing the gear ratio is performed by feedback control based on a deviation between a target value and an actual value, and the target value or other target value. In a transmission control device for a continuously variable transmission for a vehicle that is executed by feedforward control based on, a shift limiting means that limits a shift control amount by the feedforward control when performing a shift that is not intended by the driver is provided. A shift control device characterized by the above.

  According to a second aspect of the present invention, the shift limiting means can be configured to prohibit the feedforward control or correct the control amount by the feedforward control to be relatively small.

  The means for the correction is a means for correcting the control amount by the feedforward control or a value for obtaining the control amount by a predetermined coefficient so as to be relatively small as described in claim 3. It can be.

  Further, as described in claim 4, the correction means is a means that adopts a value determined in advance according to a deviation between the target value or another target value and an actual value as the coefficient. Can do.

  Further, as described in claim 5, the shift limiting means in the present invention is a means for limiting the shift control amount by the feedforward control for a predetermined time from the start of the shift to the end thereof. be able to.

  On the other hand, the shift not intended by the driver in the present invention is a gear ratio so as to increase the rotational speed of a power source connected to the input side of the continuously variable transmission. Or a shift that decreases the gear ratio so as to decrease the rotational speed of the power source connected to the input side of the continuously variable transmission upon completion of the shift, or As described above, the speed of the power source connected to the input side of the continuously variable transmission is increased to increase the gear ratio so as to decrease the vehicle speed, or the input of the continuously variable transmission is connected to the input side of the continuously variable transmission. The speed change is made to decrease the speed ratio so as to increase the vehicle speed by decreasing the rotational speed of the power source, or the amount of increase or decrease of the target speed ratio is predetermined as described in claim 8. Shifting more than a certain amount It may be at or Re.

  The continuously variable transmission according to the present invention is a belt-type continuously variable transmission that changes the gear ratio by changing the groove width of the pulley around which the belt is wound. be able to.

  According to the present invention, in a continuously variable transmission such as a belt-type continuously variable transmission, when a gear shift that is not intended by the driver occurs, such as a coast downshift or a gear shift for warming up an internal combustion engine, the gear shift is performed. A control amount by feedforward control for execution is limited. This is because, for example, a predetermined variable or target value used in the feedforward control is set or corrected to a relatively small value, or a predetermined coefficient (or gain) is set so that the control amount obtained by calculation becomes relatively small. ) And so on. As a result, according to the present invention, since the shift control amount at the time of the shift not intended by the driver is relatively small, the shift speed becomes slower than the so-called normal shift intended by the driver, and the change of the drive torque And the change in the rotational speed of the power source can be mitigated to prevent or suppress the feeling of strangeness.

  In particular, according to the sixth aspect of the present invention, when the gear ratio is increased unintentionally by the driver or when the increased gear ratio is decreased, the rapid gear shift is suppressed, so that the drive torque increases. Thus, it is possible to prevent or suppress a shock or deterioration of riding comfort, or to prevent or suppress a sudden change in the rotational speed of the power source and a sense of discomfort associated therewith.

  Further, according to the invention of claim 7, since the so-called engine brake is prevented from acting suddenly, it is possible to prevent or suppress the shock or the deterioration of the riding comfort, or the rapid change in the rotational speed of the power source. And the accompanying discomfort can be prevented or suppressed.

  According to the eighth aspect of the present invention, the amount of increase or decrease in the target gear ratio (including the target value of the input rotational speed for the continuously variable transmission) is relatively large, and the gear shift is not intended by the driver. In the case of gear shifting, the amount of control by feedforward control is limited, so that unintended sudden gear shifting is prevented or suppressed. Is prevented.

  Further, according to the ninth aspect of the present invention, it is possible to maintain a good shift response of a normal shift in a belt-type continuously variable transmission, and relatively reduce the shift speed when shifting is not intended by the driver. Thus, the uncomfortable feeling can be prevented or suppressed.

  Next, the present invention will be described based on specific examples. First, a continuously variable transmission 1 and its hydraulic control system to which the present invention can be applied will be described. FIG. 9 schematically shows a basic configuration of the belt-type continuously variable transmission 1, in which a driving pulley (primary pulley) 2 and a driven pulley (secondary pulley) 3 have their respective central axes parallel to each other. They are arranged at a predetermined interval. The drive pulley 2 can change the width of a so-called V-groove around which the belt 4 is wound. For this reason, the drive pulley 2 moves back and forth in the axial direction with a fixed sheave (fixed pulley piece) 5 fixed in the axial direction. And a movable sheave (movable pulley piece) 6 that approaches and separates from the fixed sheave 5. A hydraulic actuator (specifically, a hydraulic cylinder) 7 for moving the movable sheave 6 back and forth is provided on the back side of the movable sheave 6 (opposite to the fixed sheave 5). The opposing surfaces of the fixed sheave 5 and the movable sheave 6 are tapered surfaces having a constant taper angle, and the V groove is formed by these tapered surfaces.

  The driven pulley 3 is basically the same as the driving pulley 2 except that the positions of the fixed sheave and the movable sheave are opposite to the driving pulley 2 described above, and are opposed to each other on the same axis. A fixed sheave 8 and a movable sheave 9 that moves back and forth with respect to the fixed sheave 8. The so-called V formed between opposing surfaces of the fixed sheave 8 and the movable sheave 9 (tapered surface at a constant angle). The width of the groove is changed widely and the winding radius of the belt 4 is changed. A movable sheave 9 on the outer driven pulley 3 is arranged in the radial direction of the fixed sheave 5 in the driving pulley 2, and a fixed sheave 8 on the outer driven pulley 3 is arranged in the radial direction of the movable sheave 6 in the driving pulley 2. ing. Further, a hydraulic actuator (specifically, a hydraulic cylinder) 10 for moving the movable sheave 9 back and forth is provided on the back side of the movable sheave 9 (on the opposite side to the fixed sheave 8).

  The continuously variable transmission 1 can be employed as a transmission for a vehicle. Therefore, the drive pulley 2 is connected to a power source 11 such as an internal combustion engine or an electric motor via a start clutch, a torque converter, or the like. ing. The driven pulley 3 is connected to driving wheels (not shown) via an output shaft, a differential, a propeller shaft, or the like.

  In the belt 4, a large number of metal pieces (sometimes referred to as blocks) sandwiched between the V grooves of the pulleys 2 and 3 are arranged in a ring shape, and these metal pieces are referred to as hoops. It is formed by binding with a band. Therefore, since the total length is limited by the hoop, when the belt 4 is sandwiched between the pulleys 2 and 3, a force that pushes the belt 4 outward in the radial direction acts by the inclined surface (taper surface) of the V groove, As a result, a tension is applied to the belt 4 and a contact pressure between the belt 4 and each pulley 2 and 3 is generated, and the belt 4 and each pulley 2 and 3 are affected by a frictional force determined by the contact pressure and the friction coefficient. Torque is transmitted between them. Thus, the pressure which clamps the belt 4 is a clamping pressure, and is set by the hydraulic actuator 10 on the driven pulley 3 side, for example.

  On the other hand, when the pressure sandwiching the belt 4 in either one of the pulleys 2 and 3 is relatively increased or decreased, the belt 4 has a radius of the pulleys 2 and 3 against the tension of the belt 4. The belt 4 is pushed inward in the radial direction or pushed outward in the radial direction at the same time in the other pulleys 3, 2. Such a change in the winding radius is the execution of the speed change, which is executed by the hydraulic actuator 7 on the drive pulley 2 side, for example.

  Shifting in the continuously variable transmission 1 is configured to be performed by changing the groove width of the drive pulley 2 and changing the winding radius of the belt 4 around the pulleys 2 and 3. The hydraulic control circuit for this purpose will be described. The upshift control valve 12 and the downshift control valve 13 are connected to the hydraulic actuator 7 on the drive pulley 2 side.

  The upshift control valve 12 is a valve that controls the supply of pressure oil to the hydraulic actuator 7 on the drive pulley 2 side, and is configured to operate according to the signal pressure from the solenoid valve 14. More specifically, the upshift control valve 12 is selected as the input port 15 connected to the hydraulic actuator 7 and connected to the input port 15 to which the line pressure PL or its correction pressure, which is the original pressure of the entire apparatus, is supplied. And an output port 16 that is communicated with each other, and a signal pressure port 17 that operates a valve element (not shown) when a signal pressure corresponding to a duty ratio is applied from the solenoid valve 14. Reference numeral 18 denotes a spring, which is arranged so as to apply an elastic force in a direction against the signal pressure. Accordingly, pressure oil is supplied to the hydraulic actuator 7 in accordance with the duty ratio.

  The downshift control valve 13 is a valve for executing control to discharge the pressure oil from the hydraulic actuator 7 on the drive pulley 2 side, and is configured to operate by a signal pressure from the solenoid valve 19. . More specifically, the downshift control valve 13 has an input port 20 connected to the hydraulic actuator 7, a drain port 21 selectively communicated with the input port 20, and a signal pressure corresponding to the duty ratio. A signal pressure port 22 for operating a valve body (not shown) is provided by being added from the solenoid valve 19. Reference numeral 23 denotes a spring, which is arranged so as to apply an elastic force in a direction against the signal pressure. Accordingly, the hydraulic oil is discharged from the hydraulic actuator 7 in accordance with the duty ratio.

  An electronic control unit (ECU) 24 having a function of controlling the shift is provided. The electronic control unit 24 is mainly composed of a microcomputer, and performs calculations based on input data such as the accelerator opening, the vehicle speed, the rotational speed of the power source 11 and data stored in advance. The shift ratio is determined, the duty ratio to be output is calculated based on the shift, and output. In addition, the electronic control unit 24 is configured so that the driven pulley 3 holds the belt 4 and controls the holding pressure for setting the transmission torque capacity in the continuously variable transmission 1.

  Therefore, in the continuously variable transmission 1 described above, a target gear ratio or a target input rotational speed (a target rotational speed of the power source 11 or the driving pulley 2) is set based on the traveling state of the vehicle such as the accelerator opening and the vehicle speed. The electronic control unit 24 is configured to output a control signal to one of the solenoid valves 14 and 19 so that the actual gear ratio and the input rotation speed coincide with the target values. Then, when either solenoid valve 14 or 19 outputs a signal pressure corresponding to the input duty ratio, the pressure oil is supplied from the upshift control valve 12 to the hydraulic actuator 7 on the drive pulley 2 side, and the pressure is increased. The shift is executed, or the hydraulic oil is discharged from the hydraulic actuator 7 via the downshift control valve 13, and the downshift is executed.

  The above-mentioned upshift and downshift shift control includes feedback control based on a deviation between a target value such as a target input speed and a target gear ratio and an actual value such as an actual input speed and a gear ratio, and detected data. This is executed by feedforward control that obtains and outputs a control amount based on (or target value). The control amount in the feedforward control is a control command signal for achieving the target shift, and specifically, is a duty ratio output to any one of the solenoid valves 14 and 19.

  FIG. 10 is a flowchart for explaining the basic contents of the shift control. First, the target primary pulley rotational speed NINT is calculated (step S001). This is calculated based on the accelerator opening and the vehicle speed when cooperatively controlling the power source (specifically, the engine) 11 and the continuously variable transmission 1. More specifically, the required driving force is obtained based on the accelerator opening and the vehicle speed at that time. This is obtained from a map prepared in advance, for example. The required output of the engine 11 is calculated from the required driving force and the vehicle speed, and the engine speed at which the required output is output with the minimum fuel consumption is obtained using the map. The input rotational speed of the continuously variable transmission 1 corresponding to the engine rotational speed thus obtained is the target primary pulley rotational speed NINT. The load of the engine 11 is calculated based on the target output and the engine speed, and the throttle opening of the engine 11 is controlled so as to achieve the target output.

  On the other hand, the smoothing correction rotational speed (delay correction smoothing value) NOUTHO of the secondary pulley rotational speed NOUT is calculated (step S002). The secondary pulley rotation speed NOUT is detected by an appropriate sensor, and the smoothing correction rotation speed NOUTHO is obtained by filtering this. This annealing process (filtering process) is a process for removing noise (disturbance component) included in the detection signal, but the factor and degree of the noise are not necessarily uniform. The processing coefficient is preferably changed according to the factor or degree of noise or disturbance.

  Next, the target gear ratio RATIOT is calculated using the smoothing correction rotational speed NOUTHO (step S003). That is, since the gear ratio is a ratio between the rotation speed of the primary pulley and the rotation speed of the secondary pulley, the target transmission gear ratio RATIOT is the smoothed correction rotation speed NOUTHO of the target primary pulley rotation speed NINT and the secondary pulley rotation speed NOUT described above. It is calculated as a ratio.

  In the continuously variable transmission 1 shown in FIG. 9, the gear ratio is set in accordance with the wrapping radius of the belt 4 around the pulleys 2 and 3, so the position WDX of the movable sheave 6 for achieving the target gear ratio RATIOT is Calculated (step S004). That is, since the gear ratio and the position WDX of the movable sheave 6 are geometrically determined based on the shape of the pulley, the relationship between the target gear ratio RATIOT and the position WDX of the movable sheave 6 is prepared in advance as a map. The position WDX of the movable sheave 6 is obtained from the map and the target gear ratio RATIOT.

  The target primary pulley rotational speed NINT described above is not set as a rotational speed to be finally reached, but is set as a target value every moment, so that the target gear ratio RATIOT based on it is also a value that changes every moment. Is calculated as Therefore, the position WDX of the movable sheave 6 is obtained as a position for each time. Therefore, in the next step S005, the moving amount DXT of the movable sheave 6 for a predetermined time is calculated. This can be obtained as a moving average of the position WDX of the movable sheave 6.

  Next, the flow rate value QIN of the pressure oil with respect to the hydraulic actuator 7 on the primary pulley 2 side required to realize the moving amount DXT of the movable sheave 6 for the predetermined time to achieve the target speed ratio RATIOT change amount is calculated. (Step S006). The point is the product of the sectional area of a piston (not shown) in the hydraulic actuator 7 and the moving amount DXT of the movable sheave 6.

  Control of the supply and discharge of the pressure oil to the hydraulic actuator 7 on the primary pulley 2 side is performed by duty control of the solenoid valves 14 and 19 shown in FIG. 9, and the flow rate of the pressure oil corresponding to the duty ratio is Since it relates to the differential pressure between the inflow port and the outflow port, first, the differential pressure (primary pulley oil inflow / outlet differential pressure) SAATU is calculated (step S007). For this, data obtained by control based on a predetermined model may be used. Based on the map between the differential pressure SAATU and the flow rate value QIN, a control amount (FF control amount) DQSCFF in feedforward control is calculated (step S008).

  Since feedback control for eliminating the deviation between the target position of the primary pulley 2 and the actual position is also executed, a so-called feedback control amount (FB control amount) DQSCFB is calculated based on the deviation and feedback gain. (Step S009). Based on the calculated control amounts DQSCFF and DQSCFB, a shift output control amount (specifically, the duty ratio of the solenoid valves 14 and 19) is calculated (step S010).

  In the above-described shift control shown in FIG. 10, an accelerator pedal (not shown) is operated, and accordingly, the vehicle speed changes, or the vehicle speed does not operate without operating the accelerator pedal according to changes in the driving environment such as the road surface gradient. This is so-called normal shift control in the case of a change. The shift control device according to the present invention is configured to execute a so-called special shift control for a shift not intended by the driver, in addition to the so-called normal shift control described above.

  FIG. 1 is a flowchart showing an example of the control. When the feedforward control amount (FF control amount) DQSCFF is calculated in step S008 shown in FIG. 10 described above, the shift by the control including the feedforward control is performed by the driver. It is determined whether or not the shift is not intended by the (driver) (step S0081). The shift not intended by the driver is a coast downshift for applying the engine brake, a downshift that is set to a large gear ratio so as to increase the rotation speed in order to warm up the engine 11, and the downshift is completed. This is an upshift in which the gear ratio is reduced after the shift, or an upshift in which the speed is limited so that the gear ratio does not become too small when climbing. These shift determinations are based on the fact that the vehicle speed is not less than the predetermined value when the accelerator pedal is not depressed, the engine water temperature is not more than the predetermined temperature, the relationship between the accelerator pedal depression amount and acceleration, etc. Judgment can be made.

  If a negative determination is made in step S0081, this routine is temporarily terminated without performing any particular control. On the other hand, if an affirmative determination is made in step S0081, it is determined whether or not there is a restriction request for the feedforward control amount (step S0082). The restriction request is a prohibition of feedforward control that substantially eliminates the feedforward control amount obtained in step S008 described above, or so-called gradual change control that makes the change in the feedforward control amount slower than usual. And limiting the feedforward control amount to a small value.

  If a negative determination is made in step S0082, this routine is temporarily terminated without performing any particular control. On the other hand, when a positive determination is made in step S0082, a restriction process is performed in accordance with the restriction request (step S0083). That is, in a shift not intended by the driver, the feedforward control is prohibited and the shift is controlled by feedback control, or the change in the feedforward control amount, that is, the output control amount is gradually changed, or the feedforward control amount is changed. The amount of shift control is reduced by the amount of restriction. As a result, the speed change speed becomes slower than the normal speed change, so that an unintended speed change is less likely to be experienced by the driver, and it is prevented or suppressed from causing an uncomfortable feeling.

  FIG. 2 is a flowchart showing an example in which the control amount is gradually changed as a restriction on the feedforward control amount. Step S0082 shown in FIG. 1 is a gradual change of the feedforward control amount (FF control amount). 1 is replaced with a control step (step S0083-1) for gradually changing the feedforward control amount, and other steps are shown in FIG. 1 is the same as the flowchart shown in FIG.

  The determination in step S0082-1 shown in FIG. 2 can be executed by determining whether or not the FF control amount at that time is equal to or greater than the control amount DQSCFF calculated in step S008. In the control in step S0083-1, a value (gradual change amount) to be added for each execution cycle time of the routine shown in the flowchart of FIG. 2 is determined in advance, and the value DQSCFF (i immediately before the feedforward control amount is set. The gradual change amount is added to -1), and the addition is repeated until the value calculated in step S008 is reached.

  FIG. 3 is a flowchart showing an example in which the control is prohibited as a restriction on the feedforward control amount. Step S0082 shown in FIG. 1 is a request for prohibiting the feedforward control amount (FF control amount). 1 is replaced with a control step (step S0083-2) for inhibiting the feedforward control amount, and the other steps are shown in FIG. It is the same as the flowchart shown.

  The determination in step S0082-2 shown in FIG. 3 can be executed by determining whether or not a predetermined time has elapsed, or the absolute value of the deviation between the rotational speed NINC to be achieved by the primary pulley 2 and the actual rotational speed NIN. It can be executed by determining whether the value is equal to or less than a predetermined value. The control in step S0083-2 is executed by replacing the feedforward control amount DQSCFF calculated in step S008 described above with “0”. Therefore, the shift control amount does not include a control amount based on the feedforward control, and the shift is substantially controlled by feedback control.

  FIG. 4 shows a case where the control shown in FIG. 2 described above and the control shown in FIG. 3 are executed in the coast downshift as an example of the shift not intended by the driver, and the cases shown in FIGS. Shows changes in primary pulley rotation speed, feedforward control amount (FF control amount), output control amount (FF + FB), and accelerator opening when normal shift control is executed without executing the so-called limit control shown in FIG. Yes. When the accelerator pedal is returned (accelerator OFF), coast control is turned ON, the rotational speed NINC to be achieved for the primary pulley 2 is set, and the target rotational speed NINT having a predetermined delay with respect to the rotational speed is set. Is done.

  In normal shifting, the feedforward control amount is obtained based on the target rotational speed NINT, and the feedback control amount is calculated based on the deviation between the target rotational speed NINT and the actual rotational speed. Then, as shown by line A in FIG. 4, the FF control amount and the output control amount increase rapidly. Accordingly, the pressure is suddenly discharged from the hydraulic actuator 7 on the primary pulley 2 side, and as a result, the winding radius of the belt 4 is reduced, so that the primary pulley rotational speed increases following the target rotational speed NINT. In other words, in the case of a normal shift, the responsive shift is good, but in the case of an unintended shift, a relatively sudden downshift occurs, resulting in a sudden change in driving torque, an increase in engine speed, etc. May be uncomfortable.

  On the other hand, when the control shown in FIG. 2 is executed, the FF control amount is gradually changed as shown by the line B in FIG. 4, and the change in the output control amount is alleviated accordingly. As a result, the gradient of increase in the primary pulley rotation speed becomes gentle, and the change in the drive torque and the change in the engine rotation speed are mitigated accordingly, so that the driver's uncomfortable feeling can be prevented or suppressed.

  In addition, when the control shown in FIG. 3 is executed, the feedforward control is prohibited and the FF control amount becomes “0” as shown by the C line in FIG. Amount. As a result, the gradient of increase in the primary pulley rotation speed becomes gentle, and the change in the drive torque and the change in the engine rotation speed are mitigated accordingly, so that the driver's uncomfortable feeling can be prevented or suppressed.

  Furthermore, the example shown in FIG. 5 is an example in which the feedforward control amount is limited to a relatively small value for a predetermined time. That is, the FF control amount is calculated (step S008), and it is then determined whether or not the shift to be executed is a shift not intended by the driver (step S0081). If an affirmative determination is made in step S0081, it is determined whether or not the elapsed time since the determination is established is within a predetermined time (step S0082-3). For example, the predetermined time is equal to or less than the time when the shift is completed when the normal shift control is performed, and longer than the time when the output control amount starts to decrease from the maximum value when the normal shift control is performed. is there.

  If the determination in step S0082-3 is affirmative, the gain coefficient GAIN is changed (step S0083-3). This gain coefficient GAIN is for correcting the FF control amount calculated in step S008, and is set to a value not less than “0” and not more than “1”. As an example, the primary pulley 2 can be set to a value set according to the deviation NINCD between the rotational speed NINC to be set and the actual rotational speed NIN, or the FF control amount is not reflected in the shift control. It can be set to “0”.

  Next, the FF control amount is updated (step S0084-3). Specifically, the value obtained by multiplying the gain coefficient GAIN by the FF control amount DQSCFF calculated in step S008 is adopted as the FF control amount DQSCFF (i) at that time.

  If the determination in step S0081 is negative, or if the predetermined time has elapsed and the determination is negative in step S0082-3, the process proceeds to step S0084-3. In this case, since the gain coefficient GAIN is not changed, the value becomes “1”, and therefore, the FF control amount DQSCFF calculated in step S008 is adopted.

  FIG. 6 shows a time chart when the control shown in FIG. 5 is executed. FIG. 6 also shows the deviation NINCD. When coast control is started by accelerator OFF, the FF control amount is corrected by the gain coefficient GAIN at that time. When a value corresponding to the rotational speed deviation NINCD is adopted as the gain coefficient GAIN, the FF control amount and the output control amount are suppressed as shown by the line B1 in FIG. 6, and as a result, the primary pulley rotational speed NIN Change will be gradual. Further, when “0” is adopted as the gain coefficient GAIN, the feedforward control amount is not reflected in the shift control, so that the output control amount is further reduced as shown by the C1 line in FIG. The change in the primary pulley rotational speed NIN becomes more gradual. Then, when the predetermined time has elapsed, the gain coefficient is set to “1”, and the same control as the normal control is executed. At that time, since the output control amount is small, the gear ratio does not change greatly. Therefore, in the case of a shift not intended by the driver, the change in the gear ratio and the accompanying change in the engine speed become gradual, so that the driver's uncomfortable feeling can be prevented or suppressed.

  Each example shown in FIG. 4 and FIG. 6 is an example of a downshift, but as described above, the present invention can also be applied to an upshift that is not intended by the driver. One example is an example in which the gear ratio is increased after the coast downshift control is completed, and this example is shown in FIG. 7 by a time chart. FIG. 7 shows a case where the control shown in FIG. 2 and the control shown in FIG. 3 are executed at the end of the coast downshift control as an example of the shift not intended by the driver. And changes in primary pulley rotation speed, feedforward control amount (FF control amount), output control amount (FF + FB), and accelerator opening when normal shift control is executed without executing the so-called limit control shown in FIG. Is shown. That is, when the accelerator pedal is depressed (accelerator ON), the coast control is turned OFF, and accordingly, the rotational speed NINC to be achieved for the primary pulley 2 is set, and the target having a predetermined delay with respect to the rotational speed is set. The rotation speed NINT is set.

  In normal shifting, the feedforward control amount is obtained based on the target rotational speed NINT, and the feedback control amount is calculated based on the deviation between the target rotational speed NINT and the actual rotational speed. Then, as shown by the A2 line in FIG. 7, the FF control amount and the output control amount increase rapidly. Therefore, the pressure oil is suddenly supplied to the hydraulic actuator 7 on the primary pulley 2 side. As a result, the winding radius of the belt 4 increases, and the primary pulley rotational speed decreases following the target rotational speed NINT. In other words, in the case of a normal shift, the responsive shift is good, but in the case of an unintended shift, a relatively abrupt upshift occurs, resulting in a sudden change in driving torque, a decrease in engine speed, etc. May be uncomfortable.

  On the other hand, when the control shown in FIG. 2 is executed, the FF control amount is gradually changed as shown by the line B2 in FIG. 7, and the change in the output control amount is alleviated accordingly. As a result, the gradient of decrease in the primary pulley rotation speed becomes gentle, and the change in the drive torque and the change in the engine rotation speed are mitigated accordingly, so that the driver's uncomfortable feeling can be prevented or suppressed.

  When the control shown in FIG. 3 is executed, the feedforward control is prohibited and the FF control amount becomes “0” as shown by the C2 line in FIG. Amount. As a result, the gradient of decrease in the primary pulley rotation speed becomes gentle, and the change in the drive torque and the change in the engine rotation speed are mitigated accordingly, so that the driver's uncomfortable feeling can be prevented or suppressed.

  Next, FIG. 8 shows a time chart when the above-described control shown in FIG. 5 is executed for a shift not intended by the driver. FIG. 8 also shows the deviation NINCD. When coast control is terminated by accelerator ON, the FF control amount is corrected by the gain coefficient GAIN at that time. When a value corresponding to the rotational speed deviation NINCD is adopted as the gain coefficient GAIN, the FF control amount and the output control amount are suppressed as shown by the line B3 in FIG. 8, and as a result, the primary pulley rotational speed NIN Change will be gradual. Further, when “0” is adopted as the gain coefficient GAIN, the feedforward control amount is not reflected in the shift control, so that the output control amount is further reduced as shown by the line C3 in FIG. The change in the primary pulley rotational speed NIN becomes more gradual. Then, when the predetermined time has elapsed, the gain coefficient is set to “1”, and the same control as the normal control is executed. At that time, since the output control amount is small, the gear ratio does not change greatly. Therefore, in the case of a shift not intended by the driver, the change in the gear ratio and the accompanying change in the engine speed become gradual, so that the driver's uncomfortable feeling can be prevented or suppressed.

  Here, the relationship between the above specific example and the present invention will be briefly described. The functional means of the above-described step S0083, step S0083-1, step S0083-2, step S0083-3, and step S0084-3 are as follows: This corresponds to the shift limiting means of the present invention. In particular, the functional means in step S0083-2 corresponds to the prohibiting means in claim 2, and the functional means in steps S0083-1 and S0083-3 and step S0084-3 are the correcting means in claim 2. It corresponds to.

  The present invention is not limited to each of the above specific examples, and the value to be corrected by the coefficient is not limited to the above FF control amount. The primary pulley movement amount for obtaining the FF control amount and its value It may be a flow rate integrated value or the like. The present invention can also be applied to shift control of a continuously variable transmission other than a belt type continuously variable transmission. Further, the present invention can be applied to a device configured to execute the shift control by pressure control without using the flow control of the pressure oil. Furthermore, the shift not intended by the driver in the present invention can be a shift in which the increase amount of the transmission ratio is equal to or greater than a predetermined amount. By limiting the feedforward control amount at the time of such a shift, it is possible to prevent or suppress sudden changes in the driving force, the number of revolutions of the power source, etc. without intention, and to avoid a sense of incongruity.

It is a flowchart for demonstrating the example of basic control by the transmission control apparatus of this invention. It is a flowchart for demonstrating the example which changes the controlled variable gradually as a restriction | limiting of a feedforward controlled variable. It is a flowchart for demonstrating the example which prohibits the control as a restriction | limiting of a feedforward control amount. When the coast control is ON, the primary pulley rotation speed and the FF control when the feedforward control amount is not restricted, when the restriction is performed in the control example of FIG. 2, and when the restriction is performed in the control example of FIG. 3 is a time chart schematically showing changes in the amount and output control amount. It is a flowchart for demonstrating the example which correct | amends the control amount with a gain coefficient as a restriction | limiting of a feedforward control amount. Time when the control shown in FIG. 5 is performed when the coast control is ON, and the time schematically showing changes in the primary pulley rotational speed, rotational speed deviation, FF control amount, and output control amount when the feedforward control amount is not limited It is a chart. When the coast control is OFF, the primary pulley rotation speed and the FF control when the feedforward control amount is not limited, when the limitation is performed in the control example of FIG. 2, and when the limitation is performed in the control example of FIG. 3 is a time chart schematically showing changes in the amount and output control amount. Time when the control shown in FIG. 5 is performed when coast control is OFF, and the time schematically showing changes in the primary pulley rotational speed, rotational speed deviation, FF control amount, and output control amount when the feedforward control amount is not limited It is a chart. It is a figure which shows typically the continuously variable transmission made into object by this invention, and its hydraulic system. It is a flowchart for demonstrating normal shift control by feedback control and feedforward control.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Continuously variable transmission, 2 ... Drive pulley (primary pulley), 3 ... Driven pulley (secondary pulley), 4 ... Belt, 7, 10 ... Hydraulic actuator, 12 ... Upshift control valve, 13 ... Downshift control valve, 14, 19 Solenoid valve, 24 Electronic control unit (ECU).

Claims (9)

Shifting of a continuously variable transmission for a vehicle in which actuator control for changing a gear ratio is performed by feedback control based on a deviation between a target value and an actual value and feedforward control based on the target value or another target value In the control device,
A shift control device for a continuously variable transmission for a vehicle, comprising shift limiting means for limiting a shift control amount by the feedforward control when a shift unintended by a driver is performed.   2. The vehicle according to claim 1, wherein the shift limiting unit includes any one of a prohibiting unit that prohibits the feedforward control and a correcting unit that relatively reduces a control amount by the feedforward control. Shift control device for continuously variable transmission.   The vehicle according to claim 2, wherein the correction unit includes a unit that corrects a control amount by the feedforward control or a value for obtaining the control amount with a predetermined coefficient so as to be relatively small. Shift control device for continuously variable transmission.   The vehicle correction unit according to claim 3, wherein the correction unit includes a unit that employs a predetermined value as the coefficient in accordance with a deviation between the target value or another target value and an actual value. A shift control device for a step transmission.   2. The continuously variable vehicle for a vehicle according to claim 1, wherein the shift limiting unit includes a unit that limits a shift control amount by the feedforward control for a predetermined time from the start of the shift to the end of the shift. A transmission control device for a transmission.   The continuously variable transmission is caused by a shift that increases the gear ratio so that the shift not intended by the driver increases the rotational speed of the power source connected to the input side of the continuously variable transmission, or by the end of the shift. The shift of the continuously variable transmission for a vehicle according to any one of claims 1 to 5, characterized in that the speed change is performed so as to reduce the speed ratio so as to reduce the rotational speed of the power source connected to the input side of the vehicle. Control device.   The speed change unintended by the driver increases the speed ratio so as to decrease the vehicle speed by increasing the rotational speed of the power source connected to the input side of the continuously variable transmission, or the continuously variable transmission. 6. A vehicle transmission according to any one of claims 1 to 5, characterized in that the speed change is a reduction gear ratio so as to increase the vehicle speed by decreasing the rotational speed of the power source connected to the input side of the vehicle. A shift control device for a step transmission.   6. The vehicle continuously variable transmission according to any one of claims 1 to 5, wherein the shift not intended by the driver is a shift in which an increase amount or a decrease amount of a target gear ratio is a predetermined amount or more. A transmission control device for a transmission.   9. The continuously variable transmission according to claim 1, wherein the continuously variable transmission is a belt type continuously variable transmission that changes a gear ratio by changing a groove width of a pulley around which a belt is wound. Shift control device for continuously variable transmission for vehicles.

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