JP5082943B2 - Shift control device for continuously variable transmission for vehicle - Google Patents

Description

  The present invention is suitable for a continuously variable transmission when a vehicle equipped with a continuously variable transmission represented by a V-belt type continuously variable transmission or a toroidal continuously variable transmission is in an accelerator pedal release state (accelerator off). The present invention relates to a shift control device for performing shift control.

  Vehicles must satisfy the requirements of a trade-off relationship between improved power performance and improved fuel efficiency and drivability, such as a V-belt continuously variable transmission and a toroidal continuously variable transmission. The step transmission is very useful as a means for satisfying these requirements at a high level.

  In other words, a shift control device for a continuously variable transmission for a vehicle normally follows a shift line set in advance as representing the target input rotational speed with respect to the vehicle speed for each throttle opening, and opens the throttle corresponding to the accelerator pedal depression amount detected by the sensor. The target input speed of the continuously variable transmission is determined from the speed and the vehicle speed, and the target speed ratio corresponding to the target input speed is determined so that the actual input speed reaches the target input speed. Thus, the actual transmission ratio of the continuously variable transmission is controlled to be changed.

  In addition, a shift control device for a continuously variable transmission for a vehicle normally does not reach the shift line (coast line) set to the highest gear ratio (minimum gear ratio) when the vehicle has a throttle opening degree corresponding to accelerator off. The coast point control is performed by moving the operating point of the stepped transmission and reducing the target speed ratio to the minimum to significantly reduce the target input speed and thus the actual input speed. Improve drivability.

  By the way, in the above coast control, the value of the target gear ratio is minimized, so that the driver's intended power performance can be obtained when the driver who places importance on power performance depresses the accelerator pedal immediately after releasing the accelerator pedal. There was no inconvenience.

  Therefore, in the conventional transmission control device for a continuously variable transmission for a vehicle, for example, as disclosed in Patent Document 1 by the applicant of the present application, the driving tendency of the driver is detected based on the driving operation of the driver. When there is a driving tendency that emphasizes power performance, after the accelerator off is detected, the target input speed is set to a higher speed than the normal coast line and the target gear ratio is set to the low gear ratio (large gear ratio). By performing so-called sporty coast control using the high-speed coast line, the high engine speed can be used to increase the engine responsiveness and obtain the high power performance intended by the driver. There is a case.

Also, when the driver needs high power performance, such as when the driver tends to drive with emphasis on power performance or when the driver suddenly operates the accelerator pedal or brake pedal according to the driving situation, the so-called “Gear fixed”, that is, after detecting the accelerator off, while setting the target input speed to high and setting the target gear ratio to the low gear ratio (large gear ratio), while maintaining the target gear ratio as the vehicle speed decreases After performing control to lower the target input speed, or detecting so-called "braking downshift", that is, accelerator-off and depression of the brake pedal at a speed higher than a predetermined speed, the target input speed is set to high and the target After changing the gear ratio to the low side gear ratio (large gear ratio), control was performed to lower the target input speed while downshifting the target gear ratio to a larger value as the vehicle speed decreased. By, sometimes as high power performance of the driver to increase the responsiveness of the engine is intended to obtain.
JP 2006-266288 A

  However, in the above-described conventional transmission control device for a continuously variable transmission for a vehicle, in what process the target input rotational speed is brought to a high target input rotational speed after detecting the accelerator off due to the accelerator pedal return operation. Is not disclosed, so after detecting the accelerator off, command the low target input rotational speed to the continuously variable transmission once to reach the normal coast line and set the target gear ratio to the high side gear ratio (small gear ratio) After that, the target input rotational speed on the high speed side is commanded to reset the target speed ratio to the low speed ratio (high speed ratio).

  For this reason, the conventional shift control device for a continuously variable transmission for a vehicle generates a change in the target input speed, and thus the actual input speed, in a short time at the time of shifting to a high-speed target input speed. There is room for further improvement in that the shift shock or the change in rotational speed is uncomfortable.

  Therefore, even when the present invention sets the target gear ratio to the high side gear ratio (small gear ratio) after the accelerator is turned off and resets to the low side gear ratio (large gear ratio) based on the driving operation of the driver. An object of the present invention is to propose a shift control device for a continuously variable transmission for a vehicle that does not give a driver a sense of incongruity of a shift shock or a change in rotational speed.

The present invention has been made in order to advantageously solve the above-described problems, and the shift control device for a continuously variable transmission for a vehicle according to the present invention is set based on a throttle opening and a vehicle speed based on the accelerator pedal depression amount of the vehicle. In a transmission control device for a continuously variable transmission for a vehicle that performs shift control to change an actual gear ratio in accordance with a target gear ratio to be changed, the target gear ratio is set before the return operation by a return operation to the accelerator pedal release side. Target speed ratio setting means for setting a first target speed ratio higher than the initial speed ratio, and after the first target speed ratio is set by the target speed ratio setting means, the first target speed ratio is set. Target speed ratio resetting means for resetting to a second target speed ratio lower than the speed ratio, setting to the first target speed ratio based on the driving operation of the driver, and the second target speed ratio That resetting to be done Prediction means for measuring, when the first of said prediction means that re-setting is performed to set and the second target gear ratio to a target gear ratio is expected, as the return operation is slow, the Pre-reset target gear ratio change delay means for delaying the change of the target gear ratio from the initial gear ratio toward the first target gear ratio.

  In the speed control device for a continuously variable transmission for a vehicle according to the present invention, the target speed ratio that is sequentially set and changed is set to an initial value before the return operation by the target speed ratio setting means by the return operation to the accelerator pedal release side. After setting the first target gear ratio (first predetermined value) on the high side (small gear ratio) with respect to the gear ratio, the target gear ratio resetting means is on the low side (shift speed) with respect to the first target gear ratio. The second target gear ratio (second predetermined value) is set again based on a driving operation such as an accelerator pedal operation by the driver, and the first target gear ratio. And when the prediction means predicts that the reset to the second target speed ratio will be performed, the target speed ratio change delay means before reset is performed based on the operation in the return direction of the accelerator pedal. Change speed of the target gear ratio from the ratio toward the first target gear ratio The delay.

  Therefore, according to the shift control device for a continuously variable transmission for a vehicle according to the present invention, after the target speed ratio is once set to the first target speed ratio based on the driver's operation such as an accelerator pedal operation, the first speed ratio is set. Even when resetting to the second target gear ratio on the low side (large gear ratio) with respect to the target gear ratio, the change speed of the target gear ratio toward the first target gear ratio decreases, and the target gear ratio Changes gently until the time when the second target gear ratio is reset or close to it, so that the target input speed in a short time, and therefore the actual input speed, can be avoided from changing up and down, and the speed change shock is given to the driver. It is possible to prevent the user from feeling uncomfortable with the change in rotational speed.

  Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings. FIG. 1 shows a power train of a vehicle including a continuously variable transmission control device according to an embodiment of the present invention, and its control system. The power train includes an engine 1 and a continuously variable transmission 2. With. The engine 1 is a gasoline engine, for example, but the throttle valve 3 is not mechanically connected to the accelerator pedal 4 operated by the driver but separated from the accelerator pedal 4, and the opening degree of the throttle valve 3 is electronically controlled by the throttle actuator 5. .

  The throttle actuator 5 responds to a command related to the target throttle opening tTVO determined by the general controller 21 having a normal microcomputer, and its operation amount is controlled by an engine controller 22 having a normal microcomputer. Thus, the throttle opening TVO of the throttle valve 3 is matched with the target throttle opening tTVO, and the output of the engine 1 is basically a value corresponding to the depression amount of the accelerator pedal 4 (hereinafter also referred to as the accelerator opening) APO. The target throttle opening tTVO is also controlled by a factor other than the depression amount of the accelerator pedal 4 as necessary. The engine controller 22 not only performs the throttle opening control via the throttle actuator 5, but also performs other fuel injection amount control, fuel cut control, and ignition timing control, which are not shown, which are necessary for the operation of the engine 1. Also do.

  The continuously variable transmission 2 is a well-known V-belt continuously variable transmission, and a primary pulley 7 that is drive-coupled to the output shaft of the engine 1 via a lock-up torque converter 6 and a secondary pulley that is aligned with the primary pulley 7. 8 and a V-belt 9 spanned between these pulleys. A differential gear device 11 is drivably coupled to the secondary pulley 8 via a final drive gear set 10, whereby the continuously variable transmission 2 rotationally drives a wheel (not shown) of the vehicle.

  The speed change operation of the continuously variable transmission 2 is such that, among the flanges forming the V-grooves of the primary pulley 7 and the secondary pulley 8, one movable flange is brought relatively close to the other fixed flange to make the V-groove width. The stroke position of both movable flanges is determined by the ratio of the primary pulley pressure Ppri and the secondary pulley pressure Psec from the transmission control hydraulic circuit 12.

  The shift control hydraulic circuit 12 includes a step motor 13 as a shift actuator, and the transmission controller 23 drives the continuously variable transmission 2 by driving the step motor 13 toward a step position corresponding to the target gear ratio tRTO. The continuously variable transmission is performed so that the actual gear ratio matches the target gear ratio tRTO.

  In this case, the transmission controller 23 having a normal microcomputer obtains the target gear ratio tRTO based on the shift line determined for each throttle opening TVO as shown in FIG. A target input speed (target primary pulley speed) tNpri is obtained from VSP, and target speed tRTO is obtained by dividing this target input speed tNpri by transmission output speed No (which can be obtained from vehicle speed VSP). Further, as will be described later, the target input speed tNpri is filtered with a predetermined time constant to obtain a delayed target input speed trNpri for delaying the setting change of the target speed ratio tRTO.

  Here, the coast line α shown in FIG. 2 reduces the value of the gear ratio when the accelerator is off during normal normal driving (when the accelerator pedal is released), and greatly reduces the target input speed and therefore the engine speed. When the throttle opening degree TVO = 0/8 corresponding to the accelerator pedal depression amount APO = 0 during normal driving is set in advance to perform normal coast control for improving the fuel efficiency of the engine 1, Shift control is performed so that the target input rotational speed decreases along the coast line α.

  The transmission controller 23 further outputs a lock-up (L / U) signal to the transmission control hydraulic circuit 12, and the transmission control hydraulic circuit 12 locks the torque converter 6 in accordance with this signal with a direct connection between the input and output elements. Control is also performed to bring the lockup up and release the lockup. The transmission controller 23 outputs a lockup (L / U) signal to command lockup of the torque converter 6 while the vehicle speed VSP is equal to or higher than a predetermined lockup vehicle speed VSPl, and the vehicle speed VSP is locked up. Prevents unintended engine stop by commanding the lockup release of the torque converter 6 by not outputting the lockup (L / U) signal while the vehicle speed is below the predetermined lockup release vehicle speed VSPo slightly lower than VSPl. To do.

  The general controller 21 issues a command for the target throttle opening tTVO to the engine controller 22, a command for the lockup vehicle speed VSPl and the lockup release vehicle speed VSPo to the transmission controller 23, and a sporty shift command to be described later. For this reason, the general controller 21 receives a signal from the accelerator opening sensor 24 that detects the depression amount (accelerator opening) APO of the accelerator pedal 4, and a signal from the vehicle speed sensor 25 that detects the vehicle speed VSP from the rotational speed of the wheel. The signal from the idle switch 26 that is turned on when the accelerator pedal 4 is released (when the accelerator opening APO = 0), the signal from the engine rotation sensor 27 that detects the engine speed, and the side of the vehicle A signal from the lateral acceleration sensor 28 for detecting the acceleration is input. These signals are also supplied to the engine controller 22 and the transmission controller 23 via the general controller 21, and are used for the above-described control by these controllers.

  The general controller 21 is the vehicle running state, for example, the operating speed of the accelerator pedal 4, the operating speed of a brake pedal (not shown) detected by a sensor (not shown), the acceleration / deceleration of the vehicle based on the vehicle speed VSP, and the lateral direction of the vehicle detected by the lateral acceleration sensor 28. From acceleration and the like, it is repeatedly determined every predetermined time (for example, 10 ms) whether the driver intends to perform sporty driving with a tendency toward emphasis on power performance or economy driving with a tendency toward emphasis on fuel efficiency. When the operation speed of the accelerator pedal 4 or the brake pedal or the acceleration / deceleration speed or lateral acceleration of the vehicle exceeds a predetermined threshold value a predetermined number of times or more, the driver intends to be a sporty driving with an emphasis on power performance. If not, it is determined that the driving is an economy with an emphasis on fuel consumption. When it is determined that the driver intends to perform sporty driving with an emphasis on power performance, a sporty shift command is output to the transmission controller 23, and the driver intends to focus on fuel efficiency. When it is determined that the driving is an economy with a tendency, the output of the sporty shift command to the transmission controller 23 is stopped.

  When the driver operates the accelerator pedal 4 in the foot return direction, the transmission controller 23 controls the continuously variable transmission 2 according to the procedure shown in the flowchart of FIG. That is, first in step S1, the engine speed and the vehicle speed are set to the target speed ratio on the low side (large gear ratio) by setting the target input speed to a high speed after detecting the accelerator off, respectively. After that, fix the release gear that reduces the target input speed while maintaining the target speed ratio as the vehicle speed decreases, or detect the accelerator input and the depression of the brake pedal at a predetermined speed or more, then input the target After setting the speed to a high speed and setting the target gear ratio to the low (high gear ratio) target speed ratio, the target speed is further reduced while the target speed ratio is further downshifted to a larger value as the vehicle speed decreases. It is determined whether or not a predetermined value (for example, an engine speed of 3000 RPM and a vehicle speed of 60 km / h) suitable for performing a braking downshift that reduces the engine speed, and the engine speed and the vehicle speed are If it is less than the fixed value, the process proceeds to step S10, and after performing normal shift control in step S10, the current program is terminated.

  When the engine speed and the vehicle speed are each equal to or higher than the predetermined values, the process proceeds to step S2, and the transmission controller 23 determines whether or not the traveling state requires the above-mentioned release gear fixing or braking downshift in this step S2. For example, it is determined from the presence / absence of a sporty shift command from the general controller 21 and the vehicle speed, and whether or not the acceleration of the accelerator pedal 4 return operation, that is, the decrease acceleration of the accelerator opening APO is greater than or equal to a predetermined value is determined from the accelerator opening sensor 24. Based on this signal, there is no sporty shift command from the general controller 21 and the vehicle speed is not equal to or higher than a second predetermined value (for example, a vehicle speed of 80 km / h) higher than the predetermined value in Step 1, or there is a sporty shift command. Or the vehicle speed is higher than the second predetermined value, but the decrease acceleration of the accelerator opening APO is If it is less than the fixed value, the target input rotational speed at that time is stored and then the process proceeds to step S10. If the normal shift control, that is, for example, the accelerator is off in step S10, the target input rotational speed is set along the coast line α. After performing the shift control to be reduced, the current program ends.

  If there is a sporty shift command from the general controller 21 or if the vehicle speed is higher than the second predetermined value and the reduction acceleration of the accelerator opening APO is higher than the predetermined value, the process proceeds to step S3. In S3, a timer for limiting the time for performing delay control in the following first filter is set, the timer starts counting, and in step S4, the first filter that is the filter before resetting the target gear ratio is set. The time constant is determined to be a predetermined value. The time constant of the first filter is determined by how much the target input rotational speed and the target gear ratio, which decrease with the decrease of the throttle opening TVO due to the decrease of the normal accelerator opening APO, is delayed with respect to the decrease of the accelerator opening APO. As the degree of delay increases, the target speed ratio decreases more slowly, and the difference from the second target speed ratio that is reset thereafter becomes smaller, so that the target input speed is The connection of input rotation speed is improved. On the other hand, if the delay is large, even if the accelerator pedal 4 is operated to return to the extent that the accelerator is not turned off, the target input rotational speed is maintained at a high speed and the target input rotational speed for the accelerator pedal operation and thus the actual input rotational speed. Followability is reduced. Therefore, for the time constant of the first filter, for example, the transmission controller 23 shortens the delay by focusing on the followability when there is a sporty shift command, and lengthens the delay by focusing on the connection when there is no sporty shift command. Decide to do.

  Next, in step S5, the transmission controller 23 sets the target based on a map representing a shift line determined for each throttle opening TVO from the throttle opening TVO based on the accelerator opening APO and the vehicle speed VSP as illustrated in FIG. The input rotational speed (target primary pulley rotational speed) tNpri is obtained, and the target input rotational speed trNpri, which is delayed by applying the first filter to the target input rotational speed tNpri, is shifted to the above-mentioned release gear fixed or braking downshift. It is calculated as the target input rotational speed toward. Accordingly, the first target speed ratio tRTO (first predetermined value) obtained by dividing the target input speed tNpri when the accelerator is off by the transmission output speed No (which can be obtained from the vehicle speed VSP when the accelerator is off). Toward the target speed ratio, the target speed ratio is delayed according to the time constant of the first filter.

  Next, the transmission controller 23 determines whether or not the accelerator is turned off in step S6. If the accelerator is not turned off, the timer count is continued in step S7, and whether or not the timer count is finished in the subsequent step S8. If not completed, the process returns to step S5, and if completed, the process proceeds to step S9. The transmission controller 23 maintains the target input rotational speed trNpri delayed at that time in step S9, and thus the delayed target gear ratio, in step S9, ends the first filter, and then performs normal shift control in step S10. After that, the program concerned is terminated. If the accelerator has been turned off in step S6, the transmission controller 23 maintains the delayed target input speed trNpri and the delayed target gear ratio in step S11 as in step S9. One filter is terminated, and then the process proceeds to step S12.

  In step S <b> 12, the transmission controller 23 determines whether to perform foot release gear fixing or braking downshift. Specifically, the determination in step S12 is made based on whether or not the brake pedal is depressed within a short predetermined time after the accelerator is turned off. If the brake pedal is not depressed, the foot release gear is fixed. If the brake pedal is depressed, it is determined that a braking downshift is to be executed.

  If it is determined in step S12 that the foot release gear is to be fixed, the transmission controller 23 determines in step S13 the time constant of the second filter, which is a filter after resetting the target gear ratio, to a predetermined value. The time constant of the second filter is set to the second target speed ratio (second speed ratio) that is reset to coincide with the target speed ratio (initial speed ratio) immediately before the foot return determination in step S2 in order to fix the foot release gear. The target gear ratio that is normally changed so as to coincide with the predetermined target value) is determined to determine how late the target gear ratio is to be changed to coincide with the second target gear ratio. The increase in the gear ratio becomes moderate, and the connection between the target input rotational speed and the actual input rotational speed is improved. On the other hand, if the delay is large, the target gear ratio is slow to reach the second target gear ratio that matches the target gear ratio immediately before the foot return determination, so that the engine brake is delayed and the accelerator pedal is delayed even though the accelerator is off. The followability of the actual input rotation speed with respect to the operation is lowered. Therefore, the transmission controller 23 also delays the delay with a focus on smoothness when there is a sporty shift command, and with a focus on smoothness when there is no sporty shift command. Decide to make it longer.

  Next, in step S14, the transmission controller 23 reads the target input rotational speed (separation gear fixed rotational speed) tNpri immediately before the foot return determination stored in the previous execution of step S2 of the program, and this target input rotational speed. The target input speed trNpri, which is delayed by multiplying tNpri by the second filter, is calculated as the post-filter target input speed that is fixed to the release gear. As a result, the second target speed ratio tRTO (the second speed ratio) obtained by dividing the target input speed tNpri immediately before the foot return determination by the transmission output speed No (which can be obtained from the vehicle speed VSP immediately before the foot return determination). Toward the predetermined value), the target gear ratio is delayed according to the time constant of the second filter.

  On the other hand, if it is determined in step S12 that the braking downshift is to be executed, the transmission controller 23 determines the time constant of the second filter, which is a filter after resetting the target gear ratio, to a predetermined value in step S15. The time constant of the second filter is set to a second target speed ratio (second speed ratio) that is reset to be larger than the target speed ratio (initial speed ratio) immediately before the foot return determination in step S2 for the braking downshift. The target speed change ratio that is normally changed so as to coincide with the predetermined value) is determined to determine how much later the target speed change ratio is changed to match the second target speed change ratio. The increase in the ratio becomes gentle, and the connection between the target input rotation speed and the actual input rotation speed is improved. On the other hand, if the delay is large, the target gear ratio is slow to reach the second target gear ratio that is large for braking downshift. The followability of the actual input rotation speed is reduced. Therefore, for the time constant of the second filter, the transmission controller 23 shortens the delay by focusing on followability when there is a sporty shift command, for example, and lengthens the delay by focusing on connection when there is no sporty shift command. Decide to be.

  Next, in step S16, the transmission controller 23 reads the target input speed tNpri immediately before the foot return determination stored in the previous execution of step S2 of the program, and multiplies the target input speed tNpri by a predetermined coefficient to increase it. The target input speed that is delayed by applying the second filter to the target input speed (braking downshift speed) tNpri is calculated as the filtered target input speed for the braking downshift. Thus, the second target shift obtained by dividing the target input speed tNpri immediately before the foot return determination by the transmission output speed No (obtained from the vehicle speed VSP immediately before the foot return determination) and multiplying by a predetermined coefficient. The target gear ratio is delayed toward the ratio tRTO (second predetermined value) according to the time constant of the second filter.

  After Steps S14 and S16, the transmission controller 23 compares the target input rotational speed at the start in the case where the control for releasing the foot-gear is fixed and the case where the control for the braking downshift is executed in Step S17. One of the values is set as the target input rotational speed at the start, and in step S18, the control for releasing the foot or fixing the braking downshift is executed according to the previous determination, and the current program is terminated.

  Therefore, Steps S1 and S2 correspond to a predicting means, an accelerator off gear ratio fixed control condition detecting means, and an accelerator off brake operation downshift control condition detecting means, and Step S4 detects a driving tendency of the target gear ratio change delay means before resetting. Step S5 corresponds to the target speed ratio setting means and the target speed ratio change delay means before resetting, steps S3 and S6 to S8 correspond to the accelerator pedal return direction speed detecting means, and steps S13 and S15 correspond to Steps S14 and S16 correspond to the target speed ratio resetting means and the target speed ratio change delaying means after resetting.

  FIG. 4 is a time chart showing the operation of the control device for the continuously variable transmission according to the above-described embodiment when the foot-gear fixing control is performed along the flow chart of FIG. If the decrease acceleration of APO is greater than or equal to a predetermined value at the time indicated by X, then the target input rotational speed decreases as the accelerator opening APO decreases, as indicated by the solid line R1, and the value of the target gear ratio also changes accordingly. However, since the target input rotational speed is multiplied by the first filter, the target input rotational speed after the filter decreases with a delay as shown by a two-dot chain line R2, and the target gear ratio is also reduced before the filter. Decreases with a delay toward the target gear ratio that gradually decreases. In the meantime, the accelerator pedal opening APO becomes 0 (accelerator off) and the target speed ratio is set to a small value (high side) of the first target speed ratio (first predetermined value). When the start determination flag for the control for fixing the release gear is turned ON at the time indicated by Y because there was no stepping on, the target input rotation speed for fixing the release gear that matches the target input rotation speed immediately before the accelerator opening APO decreases. Since the target speed ratio is reset to a second target speed ratio (second predetermined value) with a large value (low side), and the second filter is applied to the second target speed ratio. The target input rotational speed increases with a delay as indicated by a broken line R3, and the target speed ratio increases with a delay toward the second target speed ratio.

  Therefore, the first filter can prevent a decrease in the target input rotational speed at the portion indicated by the region E, and the target input rotational speed is smoothly connected before and after the target speed ratio is reset as indicated by the alternate long and short dash line R4. The input speed can be avoided to change up and down in a short time, the actual input speed also changes smoothly as indicated by the solid line R5, and the target input speed after resetting the target gear ratio by the second filter Therefore, when the target input rotational speed is decreased with a fixed speed ratio as indicated by a two-dot chain line below the point P shown in FIG. It can prevent a sense of incongruity.

  FIG. 5 is a time chart showing the operation of the control device for the continuously variable transmission according to the above-described embodiment when the braking downshift is controlled along the flow chart of FIG. 3. If the decrease acceleration of APO is greater than or equal to a predetermined value at the time indicated by X, then the target input rotational speed decreases as the accelerator opening APO decreases, as indicated by the solid line R1, and the value of the target gear ratio also changes accordingly. However, since the target input rotational speed is multiplied by the first filter, the target input rotational speed after the filter decreases with a delay as shown by a two-dot chain line R2, and the target gear ratio is also reduced before the filter. Decreases with a delay toward the target gear ratio that gradually decreases. During that time, the accelerator pedal opening APO becomes 0 (accelerator off) and the target gear ratio is set to the first target gear ratio with a small value (high side). When the start determination flag of the braking downshift is turned ON at the time indicated by Y, it corresponds to the target input rotational speed of the braking downshift that is increased by multiplying the target input rotational speed immediately before the accelerator opening APO is decreased by a predetermined coefficient. Then, the target speed ratio is reset to the second target speed ratio (second predetermined value) having a large value (low side), and the second filter is applied to the second target speed ratio, so that the target The input rotational speed increases with a delay as indicated by a broken line R3, and the target speed ratio increases with a delay toward the second target speed ratio.

  Therefore, the first filter can prevent a decrease in the target input rotational speed at the portion indicated by the region E, and the target input rotational speed is smoothly connected before and after the target speed ratio is reset as indicated by the alternate long and short dash line R4. The input speed can be avoided to change up and down in a short time, the actual input speed also changes smoothly as indicated by the solid line R5, and the target input speed after resetting the target gear ratio by the second filter Therefore, when the target input rotational speed is decreased while increasing the speed ratio, as indicated by the two-dot chain line on the upper side from the point P shown in FIG. It is possible to prevent an uncomfortable feeling of the number change.

  FIG. 6 is a time chart showing the operation of the control device for the continuously variable transmission according to another embodiment of the present invention, which is applied when the accelerator pedal is depressed and the accelerator on downshift is performed after the accelerator is turned off. As shown in the figure, when the decrease acceleration of the accelerator opening APO is greater than or equal to a predetermined value at the time indicated by X, the target input rotational speed is subsequently reduced as the accelerator opening APO is decreased as shown by the solid line R1, and accordingly Although the target speed ratio value also decreases, since the target input speed is multiplied by the first filter, the target input speed decreases with a delay as shown by a two-dot chain line R2, thereby the target speed ratio. Also, it decreases with a delay toward the target gear ratio that gradually decreases before the filter. During this time, the accelerator pedal opening APO becomes 0 (accelerator off) and the target gear ratio is set to a small value, and then the accelerator pedal 4 is depressed and the acceleration of the accelerator opening APO is indicated by Y at a predetermined time. When this is the case, the second target value with a large target speed ratio (low side) corresponding to the target input rotational speed of the accelerator on / down shift increased by multiplying the target input rotational speed immediately before the accelerator opening APO is decreased by a predetermined coefficient. Since the second target speed ratio is multiplied by the second filter, the target input rotational speed rises with a delay as shown by the broken line R3. The target gear ratio increases with a delay toward the second target gear ratio.

  Therefore, the first filter can prevent a decrease in the target input rotational speed at the portion indicated by the region E, and the target input rotational speed is smoothly connected before and after the target speed ratio is reset as indicated by the alternate long and short dash line R4. The input speed can be avoided to change up and down in a short time, the actual input speed also changes smoothly as indicated by the solid line R5, and the target input speed after resetting the target gear ratio by the second filter Since the fluctuation of the number is also reduced, it is possible to prevent the driver from feeling uncomfortable with a shift shock or a change in the rotational speed.

  In any of the operations shown in FIGS. 4 to 6, the first filter up to the intersection of the solid line indicating the first pre-filter target input speed R1 and the two-dot chain line indicating the first post-filter target input speed R2. The second post-filter target input rotational speed up to the intersection of the vertical portion of the post-target input rotational speed R2, the one-dot chain line indicating the first post-filter target input rotational speed R2 and the broken line indicating the second post-filter target input rotational speed R3 No filtering is performed on the vertical part of R3. This can prevent the target input rotational speed from dropping.

  Although the present invention has been described based on the illustrated examples, the present invention is not limited to the above-described examples and can be appropriately changed within the scope of the claims. For example, the brake is applied within a predetermined time after the accelerator is turned off. When the pedal is not depressed, the speedy coast control using the high rotation coast line β shown in FIG. 2 may be performed instead of the above-mentioned release gear fixed, and this high rotation coast line β Keeping the gear ratio higher than during normal driving when the accelerator is off (when releasing the accelerator pedal) during sporty driving that emphasizes acceleration / deceleration performance over driving, and increasing the target input speed and therefore the engine speed In order to maintain and improve the responsiveness of the engine 1, it is preset separately from the coast line α, and the accelerator pedal depression amount APO = 0/8 during sporty running When it becomes the target input rotational speed and performs shift control to decrease along the high rotation coast line beta.

  Thus, according to the shift control device for a continuously variable transmission for a vehicle of the present invention, the target speed ratio is once set to the first target speed ratio based on the driver's operation such as an accelerator pedal operation, and then the first Even when resetting to the second target speed ratio on the low side (large speed ratio) with respect to the target speed ratio, the change speed of the target speed ratio toward the first target speed ratio decreases, and the target speed change The ratio changes gently until the second target gear ratio is reset or close to it, so that it is possible to avoid changes in the target input speed in a short time, and thus the actual input speed, up and down, and to change the speed to the driver. It can prevent giving a sense of incongruity to a shock or a change in rotational speed.

  In the shift control device for a continuously variable transmission for a vehicle according to the present invention, the prediction unit includes a driving tendency detection unit that detects that the driver is performing a driving operation with an emphasis on power performance. When the driving tendency detecting means detects that the driver is driving with a focus on power performance, setting to the first target speed ratio and resetting to the second target speed ratio are performed. If the driver is driving with an emphasis on power performance, the low-side gear ratio (large gear ratio) is likely to be actively used. By doing so, it is possible to reliably avoid vertical changes in the target input rotational speed in a short time, and to stabilize controllability.

  In the shift control device for a continuously variable transmission for a vehicle according to the present invention, the predicting means includes an accelerator pedal return direction speed detecting means for detecting that the accelerator pedal is operated at a predetermined speed or more in the return direction. When the accelerator pedal return direction speed detecting means detects that the accelerator pedal is operated at a predetermined speed or more in the return direction, the setting to the first target speed ratio and the second target speed ratio are performed. If the accelerator pedal is operated at a speed higher than the predetermined speed in the return direction, the driver is operating with a tendency toward emphasis on power performance, and the low gear ratio Since there is a high possibility of actively using (large gear ratio), if this is done, it is possible to reliably avoid vertical changes in the target input rotational speed in a short time, and to stabilize controllability.

  Furthermore, in the shift control device for a continuously variable transmission for a vehicle according to the present invention, the prediction means performs an accelerator off control for fixing the target gear ratio to a low gear ratio when the accelerator pedal is released. Accelerator-off gear ratio fixed control condition detecting means for detecting that the gear ratio fixed control condition is satisfied, and that the accelerator-off gear ratio fixed control condition is satisfied. When the detection means detects, it may be predicted that the setting to the first target speed ratio and the reset to the second target speed ratio that are the same as the initial speed ratio are performed. If the condition for performing the accelerator-off gear ratio fixing control that fixes the target transmission gear ratio to the low gear ratio when the engine is released is satisfied, the accelerator pedal is released. Because it uses again the low side speed ratio even (large speed ratio) after thus obtained reliably avoid vertical change in a short time the target input rotational speed when the controllability can be stabilized.

  Further, in the shift control device for a continuously variable transmission for a vehicle according to the present invention, the predicting means sets the target speed ratio to the low side speed ratio when the accelerator pedal is released and the brake pedal is depressed. Accelerator-off-brake operation downshift control condition detecting means for detecting that a condition for performing accelerator-off-brake operation downshift control for shifting is satisfied, and the accelerator-off-brake operation downshift control condition is satisfied When the accelerator-off-brake operation downshift control condition detecting means detects this, the setting to the first target speed ratio and the reset to the second target speed ratio lower than the initial speed ratio are performed. May be predicted, the accelerator pedal is released and the brake pedal is depressed. If the conditions for the accelerator-off-brake operation downshift (braking downshift) control to change the target target gear ratio to the low gear ratio are satisfied when it is made, the accelerator pedal is released However, since the low-side gear ratio (large gear ratio) is used again, in this way, it is possible to reliably avoid a vertical change in the target input rotational speed in a short time and to stabilize the controllability.

  Furthermore, in the shift control device for a continuously variable transmission for a vehicle according to the present invention, after the target speed ratio is reset to the second target speed ratio, the second target speed ratio is changed from the first target speed ratio. A target speed ratio change delay means after resetting that delays the speed of change of the target speed ratio toward the ratio may be provided, and in this way, after the target speed ratio is reset, the target input speed can be reduced in a short time. Therefore, controllability can be stabilized.

  Furthermore, in the shift control device for a continuously variable transmission for a vehicle according to the present invention, the post-reset target gear ratio change delay means detects that the driver is performing a driving operation focusing on power performance. When the driving tendency detecting means has a detecting means and the driving tendency detecting means detects that the driver is driving with a tendency toward emphasis on power performance, the first target gear ratio is changed to the second target gear ratio. The amount by which the change speed of the target speed ratio is delayed may be reduced, and in this way, when the driver tends to focus on power performance, a quick shift suitable for the driver's intention can be performed. .

  Furthermore, in the shift control device for a continuously variable transmission for a vehicle according to the present invention, the after-reset target gear ratio change delay means resets the target gear ratio to the second target gear ratio. The target speed ratio for which the speed of change to the first target speed ratio is delayed may be set as an initial value, and the speed of change of the target speed ratio toward the second target speed ratio may be delayed. This can lead to the target gear ratio before and after the resetting, so that the controllability can be further stabilized.

  Furthermore, in the shift control device for a continuously variable transmission for a vehicle according to the present invention, the target speed ratio change delay means before resetting is performed after a predetermined time has elapsed since the prediction means predicted resetting of the target speed ratio. The process of delaying the target speed ratio changing speed may be terminated, and in this way, control hunting can be prevented.

  In the shift control device for a continuously variable transmission for a vehicle according to the present invention, the target speed ratio change delay means before resetting is a driving tendency for detecting that the driver is performing a driving operation with an emphasis on power performance. And when the driving tendency detecting means detects that the driver is performing a driving operation with an emphasis on power performance, the direction from the initial speed ratio to the first target speed ratio. The amount by which the change speed of the target gear ratio is delayed may be reduced. In this way, when the driver tends to focus on power performance, it is possible to perform a quick shift that matches the driver's intention.

It is a basic diagram which shows the power train of the vehicle provided with the control apparatus of the continuously variable transmission of one Example of this invention, and its control system. FIG. 4 is a shift pattern diagram illustrating a shift line of a control device for a continuously variable transmission according to the embodiment. It is a flowchart which shows the control program of the control apparatus of the continuously variable transmission of the said Example. It is a time chart explaining the operation example in case the control apparatus of the continuously variable transmission of the said Example performs foot release gear fixing control. It is a time chart explaining the operation example in case the control apparatus of the continuously variable transmission of the said Example performs braking downshift control after a foot separation. It is a time chart explaining the operation example in case the control apparatus of the continuously variable transmission of the said Example performs accelerator on downshift control after a foot separation.

Explanation of symbols

1 Engine 2 Continuously Variable Transmission 3 Throttle Valve 4 Accelerator Pedal 5 Throttle Actuator 6 Lockup Type Torque Converter 7 Primary Pulley 8 Secondary Pulley 9 V Belt 10 Final Drive Gear Set 11 Differential Gear Device 12 Shift Control Hydraulic Circuit 13 Step Motor 21 General Controller 22 Engine controller 23 Transmission controller 24 Accelerator opening sensor 25 Vehicle speed sensor 26 Idle switch 27 Engine rotation sensor 28 Lateral acceleration sensor

Claims (10)

In a shift control device for a continuously variable transmission for a vehicle that performs shift control to change an actual gear ratio in accordance with a target gear ratio set from a throttle opening and a vehicle speed based on an accelerator pedal depression amount of the vehicle,
Target speed ratio setting means for setting the target speed ratio to a first target speed ratio higher than the initial speed ratio before the return operation by a return operation to the accelerator pedal release side;
Target speed ratio resetting means for resetting to a second target speed ratio lower than the first target speed ratio after the first target speed ratio is set by the target speed ratio setting means;
Predicting means for predicting that the setting to the first target speed ratio and the resetting to the second target speed ratio are performed based on the driving operation of the driver;
When that resetting to configuration and the second target gear ratio to the first target gear ratio is made the prediction unit predicts, as the return operation is slow, the from the initial speed ratio first Pre-reset target gear ratio change delay means for delaying the change of the target gear ratio toward the target gear ratio of 1;
A shift control device for a continuously variable transmission for a vehicle, comprising:   The predicting means includes a driving tendency detecting means for detecting that the driver is driving with an emphasis on power performance, and the driving tendency indicates that the driver is driving with an emphasis on power performance. 2. The vehicle according to claim 1, wherein when the detection means detects, the setting to the first target speed ratio and the resetting to the second target speed ratio are predicted. A transmission control device for a continuously variable transmission.   The predicting means has an accelerator pedal return direction speed detecting means for detecting that the accelerator pedal is operated at a predetermined speed or more in the return direction, and that the accelerator pedal is operated at a predetermined speed or more in the return direction. The accelerator pedal return direction speed detecting means predicts that the setting to the first target speed ratio and the resetting to the second target speed ratio will be performed when detected. A transmission control device for a continuously variable transmission for a vehicle according to claim 1.   The prediction means detects an accelerator-off gear ratio that detects that an accelerator-off gear ratio fixing control condition for performing control to fix the target gear ratio to the low-side gear ratio when the accelerator pedal is released. When the accelerator-off gear ratio fixed control condition detecting unit detects that the accelerator-off gear ratio fixed control condition is satisfied, the setting to the first target gear ratio is provided. 4. The continuously variable transmission for a vehicle according to claim 1, wherein a reset to the second target speed ratio that is the same as the initial speed ratio is predicted. 5. Gear shift control device.   The prediction means satisfies a condition for performing an accelerator off-brake operation downshift control for shifting the target gear ratio to the low gear ratio when the accelerator pedal is released and the brake pedal is depressed. An accelerator-off-brake operation downshift control condition detecting means for detecting that the accelerator-off-brake operation downshift control condition detecting means detects that the accelerator-off-brake operation downshift control condition is satisfied. The setting to the first target speed ratio and the resetting to the second target speed ratio lower than the initial speed ratio are predicted to be performed. 5. A transmission control device for a continuously variable transmission for a vehicle according to any one of the above.   After resetting the target speed ratio to the second target speed ratio, a post-reset target that delays the change speed of the target speed ratio from the first target speed ratio toward the second target speed ratio The transmission control device for a continuously variable transmission for a vehicle according to any one of claims 1 to 5, further comprising a gear ratio change delay means.   The post-reset target gear ratio change delay means has driving tendency detection means for detecting that the driver is driving with a focus on power performance, and the driver performs a driving operation with a focus on power performance. When the driving tendency detecting means detects that, the amount by which the change speed of the target speed ratio from the first target speed ratio to the second target speed ratio is delayed is reduced. The transmission control device for a continuously variable transmission for a vehicle according to claim 6.   The target speed ratio change delay means after resetting is the target speed ratio in which the change speed to the first target speed ratio is delayed when the target speed ratio is reset to the second target speed ratio. The speed change control device for a continuously variable transmission for a vehicle according to claim 6 or 7, wherein the change speed of the target speed ratio toward the second target speed ratio is delayed with the initial value as an initial value.   The pre-reset target speed ratio change delay means ends the process of delaying the target speed ratio change speed after a predetermined time has elapsed since the prediction means predicted the target speed ratio resetting. A shift control apparatus for a continuously variable transmission for a vehicle according to any one of claims 1 to 8.   The pre-reset target gear ratio change delay means includes driving tendency detection means for detecting that the driver is driving with a focus on power performance, and the driver performs a driving operation with a focus on power performance. When the driving tendency detecting means detects that the change rate of the target speed ratio from the initial speed ratio to the first target speed ratio is reduced, The transmission control device for a continuously variable transmission for a vehicle according to any one of claims 1 to 9.

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