JP4025064B2 - Shift control device for continuously changing transmission mode when switching - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention has been improved so as to suitably perform this shift when the continuously variable transmission is switched between the automatic shift mode and the manual shift mode when a high shift to the high speed shift ratio occurs. The present invention relates to a shift control device for changing a shift mode of a step transmission.
[0002]
[Prior art]
The continuously variable transmission is represented by a toroidal type continuously variable transmission or a V-belt type continuously variable transmission, for example, a planned shift pattern as shown by a broken line in FIG. 9 (in the figure, the throttle opening TVO is 0/8) , 1/8, 8/8, only the automatic shift line is shown), the target transmission input rotational speed Nio is obtained from the throttle opening TVO (engine load) and the vehicle speed VSP so that this can be achieved. Shift control is performed in a stepless manner.
Incidentally, as is apparent from the automatic shift line shown by the broken line in FIG. 9, the target transmission input speed Nio increases as the engine load increases due to depression of the accelerator pedal. As the engine load decreases due to the return of the accelerator pedal, the continuously variable transmission shifts to the corresponding high gear ratio so that the transmission input speed decreases. Upshifted towards.
[0003]
By the way, even in the continuously variable transmission, the driver may desire a shift operation feeling like a manual transmission. In view of this requirement, manual shift stages having a plurality of fixed gear ratios as indicated by solid lines in FIG. (M1: manual 1st speed to M8: manual 8th speed, but only the manual shift speeds of M1, M2 and M8 are shown in the figure) After switching from the manual shift (M) mode to the manual shift (M) mode, every time an upshift command or a downshift command is issued by the shift lever, an upshift or a downshift is performed sequentially between the adjacent manual shift stages M1 to M8. A number of continuously variable transmissions with a manual transmission mode, in which the target transmission input rotational speed Nio is obtained from the vehicle speed VSP based on the shift lines M1 to M8 representing the gears, and the gear shift control can be performed so that this is achieved, are put into practical use. ing.
[0004]
When the continuously variable transmission is switched between the automatic transmission (D) mode and the manual transmission (M) mode, the low or high side closest to the actual transmission input rotational speed at the time of the mode switching is selected. Usually, the continuously variable transmission is shifted so that the manual shift speed is selected.
[0005]
Here, the speed of the speed change performed when the speed change mode is switched between the automatic speed change (D) mode and the manual speed change (M) mode is conventionally the actual speed change as described in, for example, Japanese Patent Laid-Open No. 2000-97302. The gear ratio between the transient target gear ratio and the ultimate gear ratio required to advance the gear shift with a predetermined response from the ratio to the final target gear ratio according to the driving state. It was determined according to the magnitude of the deviation.
[0006]
[Problems to be solved by the invention]
However, since the engine load represented by the throttle opening TVO is not reflected in the shift speed determination method at the time of the shift mode switching as described above, if the conditions other than the throttle opening TVO are the same, the throttle opening Even if the TVO is different, the shift speed when changing the shift mode is almost constant, and the shift when changing the shift mode is a high-side shift (upshift) in the direction of decreasing the input rotation speed (to the high-speed gear ratio). The following problems occur.
[0007]
That is, during high load operation with the throttle opening TVO fully opened (8/8) on the first speed manual shift stage M1 shift line in FIG. 9, the automatic shift (D) from the manual shift (M) mode at point A in FIG. ) When the mode is switched to the mode, the high-side shift in which the first speed manual shift stage M1 shift line shifts to the automatic shift line with the throttle opening TVO = 8/8 will be described. When the engine is slow, the input speed of the transmission overshoots the automatic shift line with throttle opening TVO = 8/8 while overshooting as shown by the two-dot chain line α, so the engine exceeds the rotation limit indicated by the one-dot chain line. There is a possibility that the engine will be adversely affected by over-rotation of the engine.
[0008]
On the other hand, during the operation in which the throttle opening TVO is fully opened (8/8) on the first speed manual shift stage M1 shift line in FIG. 9, the throttle opening TVO is reduced to 1/8 at the point B in FIG. High side to shift from 1st speed manual shift stage M1 shift line to automatic shift line with throttle opening TVO = 1/8 by switching the mode from manual shift (M) mode to automatic shift (D) mode The case where the shift is performed will be described. When the shift speed is high, the throttle opening TVO = the throttle opening TVO = while greatly reducing the engine rotation during a slight vehicle speed (VSP) change as indicated by the two-dot chain line β at the transmission input speed. Since the engine is on the 1/8 automatic shift line, the engine-side rotational inertia generates a feeling of pushing that temporarily accelerates the vehicle, and the driver feels uncomfortable that the vehicle is accelerated despite releasing the accelerator pedal. There is a risk of giving.
[0009]
By the way, if the engine load (throttle opening TVO) is not reflected in the determination of the shift speed at the time of switching the shift mode as in the prior art, when the shift mode is switched when the throttle opening TVO is different as in the above two examples. In the case where the shift at the time of shifting mode switching is a high-side shift (upshift) in the direction of decreasing the input rotational speed (to the high-speed side gear ratio) as described above,
Increasing the shifting speed to solve the problem of the former engine overspeed makes the latter problem of the vehicle extrusion feeling remarkable. It was impossible to realize both problem solutions together as the problem became prominent.
[0010]
The present invention makes it possible to change the shift speed of the high-side shift accompanying the mode switching according to the engine load when the mode is switched between the automatic shift (D) mode and the manual shift (M) mode, as described above. It is an object of the present invention to propose a speed change control device at the time of changing the speed change mode of a continuously variable transmission, which can realize both of the problems solved in a trade-off relationship.
[0011]
[Means for Solving the Problems]
  For this purpose, the shift control device for continuously changing the transmission mode according to the present invention is as described in claim 1.
  High-speed shift to the high-speed gear ratio generated by switching the shift mode between the automatic shift mode and the manual shift mode is configured to be performed at a higher speed as the engine load at the time of switching the shift mode is higher.Do.
[0012]
  AndIn determining the shift speed of the high-side shift accompanying the switching of the shift mode, the claims1As described in
  The gear shift speed under high engine load is set to the lower limit of the gear shift speed necessary to prevent engine overspeed.It is characterized by this.
[0013]
  In determining the shift speed of the high-side shift accompanying the switching of the shift mode, the claims2As described in
  It is preferable that the speed change speed at the time of low engine load be set to an upper limit value of the speed change speed that does not generate a push-out feeling that causes the engine-side rotational inertia to accelerate the vehicle.
[0014]
【The invention's effect】
According to the first aspect of the present invention, in order to cause the high-side shift accompanying the switching of the shift mode between the automatic shift mode and the manual shift mode to be performed at a higher speed as the engine load at this time is higher,
During high load operation, the above speed change is performed at high speed, and during low load operation, the above speed change is performed at low speed, which can prevent the problem of engine overspeed during high load operation. In addition, it is possible to prevent the problem of the feeling of pushing out the vehicle during low-load operation, and to solve both these two problems that are in a trade-off relationship.
[0015]
  AlsoClaim1According to the invention described in (1), the shift speed of the high-side shift accompanying the switching of the shift mode is set to the lower limit value of the shift speed necessary for preventing the engine from over-rotating when the engine load is high. ,
  It is possible to prevent the gear change speed from becoming higher than necessary and the gear change feeling from being deteriorated.
[0016]
  And claims2According to the invention described above, when the shift speed of the high-side shift accompanying the switching of the shift mode is low and the engine load is low, the engine-side rotational inertia due to the shift does not generate a feeling of pushing out to accelerate the vehicle. In order to set the upper limit value of the shift speed,
  It is possible to prevent the shift speed from becoming slower than necessary and deteriorating the shift feeling.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a power train of a vehicle equipped with a continuously variable transmission equipped with a shift control device at the time of shifting mode switching according to an embodiment of the present invention, together with its control system. It consists of the machine 2.
The engine 1 is an internal combustion engine, and the output can be adjusted by changing the opening of the throttle valve 3 by an accelerator pedal (not shown) operated by the driver.
[0018]
The continuously variable transmission 2 is a well-known V-belt type continuously variable transmission, and includes a primary pulley 5 that is drive-coupled to the output shaft of the engine 1 via a torque converter 4, a secondary pulley 6 that is aligned with the primary pulley 5, and both A V-belt 7 is provided between the pulleys.
Then, a differential gear device 9 is drivingly coupled to the secondary pulley 6 via a final drive gear set 8 to rotate the left and right driving wheels (not shown).
[0019]
The speed change operation of the continuously variable transmission 2 is such that, among the flanges forming the V-grooves of the primary pulley 5 and the secondary pulley 6, one movable flange is brought relatively close to the other fixed flange to make the V-groove width The width of the V-groove is increased by narrowing or conversely separating, and the winding diameter of the V-belt 7 with respect to the primary pulley 5 and the secondary pulley 6 is changed.
The stroke positions of both movable flanges are determined by the primary pulley pressure Ppri and the secondary pulley pressure Psec from the transmission control hydraulic circuit 10.
[0020]
The shift control hydraulic circuit 10 includes a step motor 11 as a shift actuator, and the transmission controller 12 drives the step motor 11 to a step position STP corresponding to a target gear ratio, which will be described later. The continuously variable transmission can be performed so that the actual speed ratio matches the target speed ratio.
[0021]
For such shift control, the transmission controller 12 is supplied with a signal from a throttle opening sensor 13 for detecting the throttle opening TVO of the throttle valve 3, and
A signal from the vehicle speed sensor 14 for detecting the vehicle speed VSP;
A signal from an input rotation sensor 15 for detecting a transmission input rotation speed (primary pulley rotation speed) Ni;
A signal from the output rotation sensor 16 for detecting a transmission output rotation speed (secondary pulley rotation speed) No;
A signal from the shift lever 17 for the driver to determine the speed change mode of the continuously variable transmission 2 is input.
[0022]
As shown, the shift lever 17 includes a parking (P) range position, a reverse travel (R) range position, a neutral (N) range position, an automatic shift (D) range (automatic shift mode) position, an engine brake. (L) In addition to having the range position in the same row, it also has a manual shift (M) mode position next to the automatic shift (D) range (automatic shift mode) position, and it corresponds when operated to these positions A range signal and a mode signal shall be output.
In the manual shift (M) mode position, the shift lever 17 is elastically supported between the upshift position (+) and the downshift (−) position, and the driver tilts the shift lever 17 to the upshift position (+). The up-shift command to the next high-side manual gear stage is issued, and every time the driver tilts the shift lever 17 to the down-shift (−) position, the down-shift command to the next low-side manual gear stage is issued. .
[0023]
The transmission controller 12 is configured as shown by a functional block diagram in FIG. 2, and controls the continuously variable transmission 2 by the following processing based on the input information described above.
The shift map selection unit 71 in FIG. 2 selects a corresponding shift map based on the shift mode signal, selection range signal, manual upshift command, and manual downshift command from the shift lever 17 in FIG.
Based on the selected shift map, the reached input rotation speed calculation unit 72 searches the throttle opening TVO and the vehicle speed VSP for a steady reaching input rotation speed Nio that should be the final target in the current driving state. Ask.
[0024]
That is, the case where the shift lever 17 is set to the automatic shift (D) mode position will be described. Upon receiving the automatic shift (D) mode signal from now on, the shift map selection unit 71 performs automatic shift as shown by a broken line in FIG. Select a pattern.
On the other hand, the reaching input rotation speed calculation unit 72 obtains the target input rotation speed Nio from the throttle opening TVO and the vehicle speed VSP based on the selected automatic shift pattern.
The transmission controller 12 determines the step position STP of the step motor 11 one by one so that the input rotation speed of the continuously variable transmission 2 finally matches the target input rotation speed Nio.
[0025]
Next, the case where the shift lever 17 is set to the manual shift (M) mode position will be described. Upon receiving the manual shift (M) mode signal from now on, the shift map selection unit 71 is illustrated by a solid line in FIG. Based on the preset shift patterns of the first speed manual shift speed M1 to the eighth speed manual shift speed M8, the upshift (+) command or the downshift (−) command from the shift lever 17 and the current manual shift speed A new manual shift speed is selected based on the comparison, and a shift pattern related to one of the newly selected manual shift speeds M1 to M8 is selected.
Then, the reaching input rotation speed calculation unit 72 obtains the target input rotation speed Nio from the vehicle speed VSP based on the selected one manual shift pattern.
The transmission controller 12 determines the step position STP of the step motor 11 one by one so that the input rotation speed of the continuously variable transmission 2 finally matches the target input rotation speed Nio, and the newly selected manual shift speed is determined. The continuously variable transmission 2 is shifted so as to be maintained.
[0026]
The shift control described above is a shift control in a steady state in which the automatic shift (D) mode or the manual shift (M) mode is continuously selected. This steady shift control and the automatic shift (D) mode In practice, the transitional shift control at the time of switching between the manual shift mode and the manual shift (M) mode is actually performed as follows.
The arrival speed ratio calculation unit 73 divides the arrival input rotation speed Nio obtained as described above by the transmission output rotation speed No, thereby achieving the arrival shift to be a steady target corresponding to the arrival input rotation speed Nio. Find the ratio io.
[0027]
The shift time constant calculation unit 74 includes a shift mode (D mode, M mode), a selection range (forward automatic shift range D, forward sport travel range L), vehicle speed VSP, throttle opening TVO, the above-mentioned speed ratio io, which will be described later. In order to determine the above-mentioned speed according to various conditions such as a transient target speed ratio Rtio0 (a target speed ratio for changing from the current speed ratio to an arrival speed ratio io at a predetermined speed) The first shift time constant Tg1 and the second shift time constant Tg2 are determined as described in detail later.
The target speed ratio calculating unit 75 calculates a transient target speed ratio Ratio0 for realizing the ultimate speed ratio io at a speed determined by the first speed time constant Tg1 and the second speed time constant Tg2 by the following calculation. Calculate and output.
[0028]
That is, as shown in FIG. 3, the difference between the ultimate transmission ratio io and the intermediate transmission ratio Ratio00 calculated in the previous routine multiplied by the first transmission time constant Tg1 is the intermediate calculated in the previous routine. By adding to the gear ratio Ratio00, the current intermediate gear ratio Ratio00 is calculated. At the same time, the difference between the intermediate gear ratio Ratio00 calculated in the previous routine and the target gear ratio Ratio0 calculated in the previous routine is The current target speed ratio Ratio0 is calculated by adding the product of the second speed time constant Tg2 to the target speed ratio Ratio0 calculated in the previous routine.
Accordingly, the first speed change time constant Tg1 and the second speed change time constant Tg2 determine the speed change response from the current speed change ratio to the reach speed change ratio io, that is, the speed change speed, by the combination of both. The shift speed can be freely determined.
[0029]
The actual transmission ratio calculation unit 78 calculates the actual transmission ratio Ratio by dividing the transmission input rotational speed Ni by the transmission output rotational speed No.
The gear ratio deviation calculating unit 79 subtracts the actual gear ratio Ratio from the target gear ratio Ratio0 to obtain a gear ratio deviation RatioERR (= Ratio0−Ratio) between the two.
The PID control unit 84 uses a predetermined feedback gain, calculates a gear ratio feedback correction amount FBrto by PID control according to the gear ratio deviation RatioERR,
The target gear ratio correction unit 85 corrects the target gear ratio Ratio0 by the gear ratio feedback correction amount FBrto to obtain a corrected target gear ratio DsrRTO (= Ratio0 + DsrRTO).
[0030]
The target step number (actuator target drive position) calculation unit 86 obtains the target step number (actuator target drive position) STP of the step motor (actuator) 11 for realizing the corrected target gear ratio DsrRTO by map search. Output to the step motor 11.
As described above, the shift from the current actual gear ratio Ratio to the ultimate gear ratio io proceeds at a shift speed determined by the shift time constants Tg1 and Tg2 obtained by the calculation unit 74, and this shift speed is determined. How the calculation unit 74 calculates the shift time constants Tg1 and Tg2 will be described in detail below.
[0031]
FIG. 4 is a main routine for calculating the first shift time constant Tg1 and the second shift time constant Tg2 performed by the calculation unit 74. First, in step S1, the first basic time is calculated based on the map for each shift time constant calculation mode. A constant TG1 and a second basic time constant TG2 are calculated.
The detailed calculation processing of the first basic time constant TG1 and the second basic time constant TG2 will be described in detail later with reference to FIGS.
Next, in step S2, the first time constant correction coefficient K01 and the second time constant correction coefficient K02 corresponding to the shift mode switching and the range switching are respectively set by the processing of FIG.
Next, in step S3, the first shift time constant Tg1 is obtained by multiplying the first basic time constant TG1 and the first time constant correction coefficient K01, and the second shift time constant Tg2 is determined as the second basic time constant TG2 and the second time. Obtained by multiplication with a constant correction coefficient K02.
[0032]
The above-described shift time constant calculation mode used in step S1 in FIG. 4 is determined by the processing in FIG. 5. Similarly, in step S1, the first basic time constant TG1 and the second basic time constant TG1 are based on the map for each shift time constant calculation mode. The process for calculating the time constant TG2 is as shown in FIG.
First, the shift time constant calculation mode determination process in FIG. 5 will be described. In step S11, it is determined whether the vehicle is stopped or slowing down or is traveling normally depending on whether the vehicle speed VSP is less than or equal to the minute set value VSPs. Determine.
If the vehicle speed VSP is equal to or higher than the set value VSPs, in step S12, whether or not the speed ratio deviation Eip (= io−Ratio0) between the ultimate speed ratio io and the target speed ratio Ratio0 is 0 or more, that is, whether io ≧ Ratio0. Whether or not it is a low-side shift (downshift) that increases the transmission input rotational speed is determined (high-side shift: upshift).
Low-side shift (downshift) and high-side shift (upshift) are the accelerator pedal depression and return operations in automatic shift (D) mode, and upshift and downshift commands in manual shift (M) mode. It also occurs when the mode is switched between the automatic transmission (D) mode and the manual transmission (M) mode.
[0033]
When it is determined in step S12 that the shift is low, the UP / DOWN flag is set to DOWN in step S13, and both the low shift flag and the sudden low shift flag indicating the shift time constant calculation mode are cleared. The constant calculation mode is determined again by the following process.
In other words, in step S14 to step S16, the absolute value of the gear ratio deviation Eip (= io-Ratio0) is compared with the set values Eip1, Eip2, and Eip3 that are set large in order. If | Eip | <Eip1, the low value is obtained in step S17. Both the side shift flag and the sudden low side shift flag are cleared.
If Eip2 ≦ | Eip | <Eip3, the low shift flag is set in step S18. If | Eip | ≧ Eip3, the sudden low shift flag is set in step S19. If Eip1 ≦ | Eip | <Eip2, step S17 to step S19. Both of these are skipped and the low-side shift flag and the sudden low-side shift flag are kept unchanged, so that this interval is set as a hysteresis region.
[0034]
When it is determined in step S12 that the gear shift is high, the UP / DOWN flag is set to UP in step S23, and both the high gear shift flag and the sudden high gear shift flag indicating the shift time constant calculation mode are cleared. The constant calculation mode is determined again by the following process.
That is, in step S24 to step S26, the absolute value of the gear ratio deviation Eip (= io-Ratio0) is compared with the set values Eip1, Eip2, and Eip3 which are set large in order. If | Eip | <Eip1, the high value is obtained in step S27. Both the side shift flag and the sudden high side shift flag are cleared.
If Eip2 ≦ | Eip | <Eip3, the high side shift flag is set in step S28. If | Eip | ≧ Eip3, the rapid high side shift flag is set in step S29. If Eip1 ≦ | Eip | <Eip2, step S27 to step S29. Both of these are skipped and the high-side shift flag and the sudden high-side shift flag are kept unchanged, so that this interval is set as a hysteresis region.
[0035]
While it is determined in step S11 that the vehicle speed VSP is less than the minute set value VSPs, that is, when the vehicle is stopped or slowing down, in step S30, the low side shift flag, the sudden low side shift flag, and the high side that constitute the shift time constant calculation mode are set. Clear all of the shift flag and the sudden high shift flag.
The set values Eip1 to Eip3 are experimental values given according to the vehicle.
[0036]
Step S1 in FIG. 4 includes the first basic time constant TG1 and the second basic time constant based on the shift time constant calculation mode (low side shift flag, sudden low side shift flag, high side shift flag, sudden high side shift flag). The process for calculating the time constant TG2 is as shown in FIG.
First, in step S31, it is determined whether the speed change mode is the automatic speed change (D) mode or the manual speed change (M) mode. If the speed change mode is the automatic speed change (D) mode, the control branches to step S32 and the following operations are performed. First basic time constant TG1 and second basic time constant TG2 are obtained.
[0037]
In step S32, it is checked whether the UP / DOWN flag is UP or DOWN. If UP / DOWN flag = UP, depending on the determination result of the sudden high-side shift flag and the high-side shift flag performed in steps S33 and S34, Select the basic time constant table.
That is, in the shift time constant calculation mode in which neither the sudden high-side shift flag nor the high-side shift flag is set, the basic time constant table TGTBL1 for that is selected in step S35,
In the shift time constant calculation mode in which only the high-side shift flag is set, the basic time constant table TGTBL2 for that is selected in step S36,
In the shift time constant calculation mode in which the sudden high side shift flag is set, the basic time constant table TGTBL3 for that is selected in step S37.
[0038]
When it is determined in step S32 that UP / DOWN = DOWN, the basic time constant table is selected as follows according to the determination result of the sudden low side shift flag and the low side shift flag performed in step S38 and step S39.
That is, in the shift time constant calculation mode in which neither the sudden low shift flag nor the low shift flag is set, the basic time constant table TGTBL4 for that is selected in step S40,
In the shift time constant calculation mode in which only the low shift flag is set, the basic time constant table TGTBL5 for that is selected in step S41,
In the shift time constant calculation mode in which the sudden low shift flag is set, the basic time constant table TGTBL6 for that is selected in step S42.
[0039]
Note that the manual shift (M) mode is determined in step S31 in the same manner as in the automatic shift (D) mode depending on the determination result of the UP / DOWN flag in step S43 being UP or DOWN. Select the corresponding individual basic time constant table.
In step S44, the first basic time constant TG1 and the second basic time constant TG2 are searched based on the individual basic time constant tables selected as described above.
[0040]
The calculation process of the first time constant correction coefficient K01 and the second time constant correction coefficient K02 related to the first basic time constant TG1 and the second basic time constant TG2 performed in step S2 of FIG. 4 is as shown in FIG.
First, in step S51, it is checked whether or not the transmission mode has been switched between the automatic transmission (D) mode and the manual transmission (M) mode. If there is no switching of the transmission mode, steps S52 to S58 are performed as follows. First, a first time constant correction coefficient K01 and a second time constant correction coefficient K02 are determined.
[0041]
First, in step S52, it is determined whether or not the range has been switched. If there is no range switching, the shift speed may remain basic. In step S53, the first time constant correction coefficient K01 and the second time constant correction coefficient K02 are both set. 1.0.
In this case, the first shift time constant Tg1 (= TG1 × K01) and the second shift time constant Tg2 (= TG2 × K02) obtained in step S3 of FIG. 4 are the first basic time constant TG1 and the second basic time constant TG2. With the same value, the speed change can be kept basic as required.
[0042]
When it is determined in step S52 that the range has been switched, the shift time constant calculation mode is checked in steps S54 and S55.
If none of the low side shift flag, the sudden low side shift flag, the high side shift flag, and the sudden high side shift flag is set as a result of the check, in step S56, the first basic time constant correction coefficient K01 is set to K0TBL1 ( 1), the second basic time constant correction coefficient K02 is K0TBL1 (2),
If the high gear shift flag or the sudden high gear shift flag is set, the first basic time constant correction coefficient K01 is set to K0TBL2 (1) and the second basic time constant correction coefficient K02 is set to K0TBL2 (2) in step S57. ,
If the low shift flag or the sudden low shift flag is set, in step S58, the first basic time constant correction coefficient K01 is set to K0TBL3 (1), and the second basic time constant correction coefficient K02 is set to K0TBL3 (2). To do.
[0043]
In step S51, when it is determined that the shift mode has been switched between the automatic shift (D) mode and the manual shift (M) mode, the same determination as in the case of determining that the range has been switched in step S52. In step S59 and step S60, the shift time constant calculation mode is checked.
If none of the low side shift flag, the sudden low side shift flag, the high side shift flag, and the sudden high side shift flag is set as a result of the check, the first basic time constant correction coefficient K01 is set to K0TBL4 in step S61. (1), the second basic time constant correction coefficient K02 is K0TBL4 (2),
If the high side shift flag or the sudden high side shift flag is set, the first basic time constant correction coefficient K01 is set to K0TBL5 (1) and the second basic time constant correction coefficient K02 is set to K0TBL5 (2) in step S62. ,
If the low shift flag or the sudden low shift flag is set, in step S63, the first basic time constant correction coefficient K01 is set to K0TBL6 (1), and the second basic time constant correction coefficient K02 is set to K0TBL6 (2). To do.
[0044]
Here, the first basic time constant correction for determining the shift speed when there is a high-side shift associated with the shift mode switching between the automatic shift (D) mode and the manual shift (M) mode is involved in the present invention. The coefficient K01 = K0TBL5 (1) and the second basic time constant correction coefficient K02 = K0TBL5 (2), that is, the first basic time constant correction coefficient K01 = K0TBL5 (1) and the second basic time constant correction coefficient K02 obtained in step S62. = K0TBL5 (2) will be described in detail.
That is, in step S62, the first basic time constant correction coefficient K0TBL5 (1) and the second basic time constant correction coefficient K0TBL5 (2) as illustrated in FIG. The time constant correction coefficient K01 and the second basic time constant correction coefficient K02 are searched.
[0045]
In the present embodiment, as is clear from FIG. 8, both the first basic time constant correction coefficient K0TBL5 (1) and the second basic time constant correction coefficient K0TBL5 (2) have a large throttle opening TVO when changing the shift mode. It is set so as to increase as much as possible (so that the shift speed increases).
As a result, the shift speed when there is a high-side shift accompanying switching of the shift mode is increased as the throttle opening TVO at the shift mode switch is larger.
[0046]
Thus, the high-side shift accompanying the switching of the shift mode between the automatic shift (D) mode and the manual shift (M) mode is performed at a higher speed as the throttle opening TVO (engine load) at this time increases. By doing so, the high-side shift is performed at a high speed during high-load operation, and the high-side shift is performed at a low speed during low-load operation, and the following effects can be achieved.
[0047]
That is, during high load operation with the throttle opening TVO fully opened (8/8) on the first speed manual shift stage M1 shift line in FIG. 9, the automatic shift (D) from the manual shift (M) mode at point A in FIG. ) A case where a high-side shift for shifting from the first speed manual shift stage M1 shift line to the automatic shift line with throttle opening TVO = 8/8 is performed by switching the mode to the mode will be described.
According to the present embodiment, the speed change speed is increased in response to the throttle opening TVO being fully opened, so that the transmission input rotational speed does not greatly overshoot as indicated by the two-dot chain line α, and the solid line δ As shown, it is possible to quickly get on the automatic shift line with the throttle opening TVO = 8/8 and avoid over-rotation in which the engine exceeds the rotation limit indicated by the one-dot chain line.
[0048]
On the other hand, during the operation in which the throttle opening TVO is fully opened (8/8) on the first speed manual shift stage M1 shift line in FIG. 9, the throttle opening TVO is reduced to 1/8 at the point B in FIG. High side to shift from 1st speed manual shift stage M1 shift line to automatic shift line with throttle opening TVO = 1/8 by switching the mode from manual shift (M) mode to automatic shift (D) mode In the case of shifting,
According to the present embodiment, the shift speed is decreased in response to the low load operation with the throttle opening TVO = 1/8, so that the transmission input rotational speed is a slight vehicle speed (as indicated by the two-dot chain line β). (VSP) The engine speed is greatly reduced during the change and the automatic transmission line with the throttle opening TVO = 1/8 is not applied, and the transmission input rotational speed is indicated by the solid line γ. Even if the accelerator pedal is released, the vehicle can be shifted to the automatic transmission line with throttle opening TVO = 1/8 while the engine speed is reduced during a large vehicle speed (VSP) change. It is possible to avoid occurrence of a situation in which the driver is given a feeling of pushing (discomfort) that is temporarily accelerated.
[0049]
Therefore, according to the present embodiment, it is possible to prevent the engine over-rotation problem from occurring when the high-side shift accompanying the shift mode switching occurs in the high load operation state, and in the low load operation state. When a high-side shift accompanying a shift mode switching sometimes occurs, it is possible to prevent the problem of the feeling of pushing out the vehicle, and it is possible to solve both these two problems that are in a trade-off relationship.
[0050]
Note that when determining the shift speed of the high-side shift accompanying the switching of the shift mode, the lower limit of the shift speed necessary to prevent the engine from over-running at high engine load is set. It is better to set the upper limit of the shift speed so that the engine-side rotational inertia due to the shift does not generate a push-out feeling that accelerates the vehicle.
In this case, it is possible to prevent the shift speed from being increased more than necessary when the engine load is high and prevent the shift feeling from deteriorating, and at the low engine load, the shift speed is decreased more than necessary and the shift feeling is deteriorated. Can be prevented.
[Brief description of the drawings]
FIG. 1 is a schematic system diagram showing a power train of a continuously variable transmission equipped vehicle equipped with a speed change mode switching control device according to an embodiment of the present invention, together with its control system.
2 is a functional block diagram showing the transmission controller in FIG. 1. FIG.
FIG. 3 is a flowchart of a control program executed by a target gear ratio calculation unit in FIG.
4 is a flowchart showing a main routine of a control program executed by a shift time constant calculating unit in FIG. 2. FIG.
FIG. 5 is a flowchart showing a shift time constant calculation mode determination process in the shift time constant calculation process of FIG. 4;
6 is a flowchart showing a basic time constant calculation process in the shift time constant calculation process of FIG. 4;
7 is a flowchart showing a time constant correction coefficient calculation process in the shift time constant calculation process of FIG. 4;
FIG. 8 is a characteristic diagram of a time constant correction coefficient for determining a shift speed at the time of high-side shift that occurs in association with switching of the shift mode.
FIG. 9 is a diagram showing a shift pattern of a continuously variable transmission used to explain the operation effect of the shift mode switching shift control device according to the embodiment shown in FIGS. 1 to 8 and the problems of the conventional device; It is.
[Explanation of symbols]
1 engine
2 continuously variable transmission
3 Throttle valve
4 Torque converter
5 Primary pulley
6 Secondary pulley
7 V belt
8 Final drive gear set
9 Differential gear unit
10 Shift control hydraulic circuit
11 Step motor
12 Transmission controller
13 Throttle opening sensor
14 Vehicle speed sensor
15 Input rotation sensor
16 output rotation sensor
17 Shift lever
71 Shift map selector
72 Ultimate input rotation speed calculator
73 Achieving transmission ratio calculation unit
74 Shift time constant calculator
75 Target gear ratio calculator
78 Actual gear ratio calculator
79 Gear ratio deviation calculator
84 PID controller
85 Target gear ratio correction unit
86 Target step number (actuator target drive position) calculator

Claims (2)

In addition to the automatic transmission mode, in a continuously variable transmission having a manual transmission mode in which a manual transmission stage having a plurality of preset fixed transmission ratios can be manually selected arbitrarily,
The high-side shift to the high-speed gear ratio generated by switching the shift mode between the automatic shift mode and the manual shift mode is performed at a higher speed as the engine load at the time of switching the shift mode is higher. and,
A continuously variable transmission characterized in that the shift speed of the high-side shift associated with the switching of the shift mode is set to a lower limit value of the shift speed necessary to prevent the engine from over-rotating at high engine loads. Shift control device for shifting mode of machine. Oite to claim 1, the transmission speed of the high-side shift due to the switching of the shift mode, at low engine load rotational inertia of the engine side by shifting without generating the extrusion feeling as to accelerate the vehicle speed A speed change control device at the time of changing a speed change mode of a continuously variable transmission, characterized in that it is set to an upper limit value of speed.

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