JP3760875B2 - Control device and method for automatic transmission - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a control device for an automatic transmission that includes a torque converter and a stepped automatic transmission mechanism, and more particularly to a device that reduces torque fluctuation (shift shock) that occurs during a shift of the automatic transmission. .
[0002]
[Prior art]
For example, as described in Japanese Patent Application Laid-Open No. 63-254256, this type of conventional control method is actually used when the input shaft rotational speed of the transmission mechanism reaches a predetermined rotational speed in order to reduce shift shock. As the mechanism has started shifting, the engine output is corrected and controlled, or as described in JP-A 64-4544, the ratio between the input shaft rotation speed and the output shaft rotation speed of the transmission mechanism, that is, There is one that grasps actual shift start and end times based on the ratio and corrects and controls engine output.
[0003]
[Problems to be solved by the invention]
However, when detecting the start of engine output correction control at the time of shifting based on the speed ratio of the speed change mechanism as described in Japanese Patent Application Laid-Open No. 64-4544, the change in speed ratio is significant in upshifting. It is difficult to detect when the torque output from the torque converter switches from the clutch before the shift (low gear side) to the clutch after the shift (high gear side), and the drive shaft torque control starts very late. I was aware. In the downshift, it is not possible to detect the time when the torque output from the torque converter switches from the clutch before shifting (high gear side) to the clutch after shifting (low gear side). There is a problem that the relationship between the gear ratios must be obtained in advance by experiments to recognize the start of drive shaft torque correction control.
[0004]
The object of the present invention is to reliably detect the torque transmission switching timing at the time of upshifting and downshifting, and to detect the control start timing of engine output, transmission hydraulic pressure, etc. An object of the present invention is to provide an automatic transmission control device and method capable of reducing torque (shift shock).
[0005]
[Means for Solving the Problems]
  A control device for an automatic transmission according to the present invention includes a post-transmission-mechanism signal detection means for detecting a rotational speed change rate of an output shaft of the automatic transmission,A pre-transmission-mechanism signal detection means for detecting the rotational speed change rate of the output shaft of the torque converter;Rough road determination means for determining that the vehicle is traveling on a rough road based on the post-shift mechanism signal detection means;Means for detecting clutch switching timing at the time of upshifting of the automatic transmission based on the signal detection means before transmission mechanism and clutch switching at the time of downshift of the automatic transmission based on the signal detection means after transmission mechanism. Has a means to detect the timeWhen the shift timing detection means and the rough road determination means determine that the vehicle is traveling on a rough road, the shift timing detection means outputs the output to the output shaft of the automatic transmission mechanism based on the shift timing detection means.engineFirst to correct torqueengineFrom the torque control mode,engineThe second that does not correct the torqueengineSwitching means for switching to the torque control mode.
[0006]
  Further, the control device for an automatic transmission according to the present invention preferably has a pre-transmission mechanism signal detecting means for detecting a rotational speed change rate of the output shaft of the torque converter, and the shift timing detecting means is arranged before the transmission mechanism. A means for detecting a clutch switching timing when the automatic transmission is upshifted based on a signal detection means, and a clutch switching timing when the automatic transmission is downshifted based on the post-transmission mechanism signal detection means. And means for performing.
[0008]
【Example】
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0009]
FIG. 1 is a block diagram of an embodiment of the present invention. The timing at which the torque output from the torque converter during upshifting (shifting from the low gear side to the high gear side) switches from the clutch before the shift to the clutch after the shift is detected using a signal before the transmission mechanism in the automatic transmission. be able to. The timing at which the torque output from the torque converter during downshifting (shifting from the high gear side to the low gear side) switches from the clutch before the shift to the clutch after the shift is detected using a signal after the shift mechanism. (See below). Therefore, by using the detection signal, it is possible to perform the engine torque control at the time of shifting which is accurate and does not require matching. In the present invention, the detection means at the time of the upshift is the signal detection means before the transmission mechanism 1, and the detection means at the time of the downshift is the signal detection means 2 after the transmission mechanism. The signal from the detection means 1 is inputted to the clutch change timing signal recognition means 3 at the time of upshift and the signal storage means 4 before clutch change at the time of upshift, and the signal from the detection means 2 is changed to the clutch change timing signal recognition means 5 at the time of downshift. And it is input to the signal storage means 6 before clutch change at the time of downshift. The recognizing means 3 and recognizing means 5 compare the current signal detected by the detecting means 1 and 2 with the stored values of the storing means 4 and 6, and determine whether or not the clutch switching time has come. When the recognizing unit 3 determines that the value is larger than the stored value, the upshift driving shaft torque correction control start signal output unit 7 outputs a control start signal such as a flag and the engine torque control unit 8 starts control of the engine torque. To do. When the recognition means 5 determines that the value is larger than the stored value, the downshift driving shaft torque correction control start signal output means 9 outputs a control start signal such as a flag and the engine torque control means 8 starts engine torque control. To do.
[0010]
FIG. 2 is a schematic configuration around the engine and the automatic transmission. The engine 10 is a four-cylinder engine in this embodiment. The engine 10 is provided with an ignition device 11. The ignition device 11 has four spark plugs 12 corresponding to the number of cylinders of the engine 10. An intake pipe 13 for taking air into the engine 10 includes a throttle valve 14 for adjusting the flow rate of air passing therethrough, a fuel injection device 15 for injecting fuel, and an amount of air supplied to the engine 10 during idling. An ISC (Idle Speed Control) valve 16 is provided. The throttle valve 14 is connected to the accelerator pedal 17 and a wire 18 so that the valve opening degree changes linearly with respect to the operation amount of the accelerator pedal 17. The fuel injection device 15 has four fuel injection valves 19 corresponding to the number of cylinders of the engine 10.
[0011]
A flywheel 21 is attached to the crankshaft 20 of the engine 10. The flywheel 21 is provided with an engine speed sensor 22 that detects the speed of the crankshaft 20, that is, the engine speed Ne. The flywheel 21 and the torque converter 23 include a pump 24, a turbine 25, and a stator 26. The output shaft of the turbine 25, that is, the torque converter output shaft 27 is directly connected to the stepped transmission mechanism 28. A turbine rotation sensor 29 that measures the turbine rotation speed Nt is attached to the torque converter output shaft 27. The stepped transmission mechanism 28 includes planetary gears 30 and 31, a band brake 32, clutches 33 and 34, and the like. The planetary gear 31 is directly connected to the propeller shaft 35. Further, a transmission output shaft rotational speed sensor 36 for detecting the rotational speed of the transmission output shaft is attached between the planetary gear 31 and the propeller shaft 35, and is also used for calculating the vehicle speed. The automatic transmission 37 is provided with a clutch such as the band brake 32 and a hydraulic circuit 38 for controlling the hydraulic pressure. The hydraulic circuit 38 is provided with a hydraulic control valve 39 that controls the hydraulic pressure in the transmission, a lockup control valve 40 that directly controls the torque converter 23 (lockup control), a shift control valve 41 that controls the shift position, and the like. ing.
[0012]
The actuator for driving the engine 10 and the automatic transmission 37 described above is controlled by the controller 42. The controller 42 is input with a throttle opening θ, a turbine rotational speed Nt, an engine rotational speed Ne, a transmission output shaft rotational speed No, a transmission oil temperature Toil, and the like, and is used for control. Further, in a special system, the turbine torque Tt detected using a torque sensor attached before the speed change mechanism as indicated by the broken arrow and the transmission output detected using a torque sensor attached after the speed change mechanism. The shaft torque To is taken into the control controller 42.
[0013]
A device (for example, an electronic control throttle 43 that is not mechanically linked to the accelerator pedal) is provided that can control the air amount independently of the operation amount of the accelerator pedal 17. In such an engine, since the air amount can be controlled by a signal from the controller 42, it is advantageous for greatly changing the engine torque or preventing deterioration of exhaust characteristics. In this case, it is necessary to provide the accelerator pedal 17 with the accelerator opening sensor 44 and input the driver's intention (required torque) to the controller 42.
[0014]
FIG. 3 shows a hardware configuration of the controller 42. A filter 45 and a waveform shaping circuit 46 for inputting signals from various sensors, a single chip microcomputer 47, and a drive circuit 48 for outputting drive control signals to actuators such as various valves are configured. The computer 47 includes a CPU 49 that executes various operations, a ROM 50 that stores programs and data to be executed by the CPU 49, a RAM 51 that temporarily stores various data and the like, a timer 52, and an SCI (Serial Communication Interface) circuit 53. And an I / O circuit 54 and an A / D converter 55. That is, the various functions of the controller 42 are achieved by the CPU 49 executing predetermined calculations using programs, data, and the like stored in the ROM 50 and RAM 51.
[0015]
As the hardware configuration of the controller 42, the above-described single chip configuration, a configuration in which a plurality of single chip microcomputers communicate via a dual port RAM, and a plurality of single chip microcomputers via a LAN (Local Area Network). And the like for communication.
[0016]
FIG. 4 shows the shift characteristics at the time of upshift, and FIG. 5 shows the shift characteristics at the time of downshift. In the upshift of FIG. 4, in the speed change mechanism of the automatic transmission shown in FIG. 2, the point at which the turbine rotation starts to change, that is, the point at which the turbine torque rises, and the point at which the turbine rotation speed change rate passes from 0 to 0, The torque transmission ratio is changed from the low gear to the high gear, that is, the low gear side clutch is switched to the high gear side clutch. These are all signals before the speed change mechanism. On the other hand, the minimum value t of the signal after the speed change mechanism, that is, the transmission output shaft torque signal.₁ Is delayed from the clutch switching point before the mechanism. Therefore, the signal before the mechanism is accurate in detecting the clutch switching point. However, since the change does not appear remarkably in the turbine rotation even in the signal before the mechanism, it is necessary to use the turbine rotation speed change rate and the turbine torque. In the downshift of FIG. 5, the clutch switching point cannot be detected by a signal before the speed change mechanism, that is, by turbine rotation. On the other hand, in the case of the signal after the transmission mechanism, that is, the transmission output shaft torque and the transmission output shaft rotation rate change rate, the minimum value t₂ Can be detected.
[0017]
As a result of the above, the start of drive shaft torque correction control at the time of upshift is controlled by the signal before the speed change mechanism, and the start of drive shaft torque correction control at the time of downshift is controlled by the signal after the speed change mechanism. In addition, matching for each shift (1-2 shift, 2-3 shift, 2-1 shift,...) Is unnecessary, and man-hours are reduced.
[0018]
FIG. 6 is a control flowchart of one embodiment. First, in process 56, the upshift flag FlgU and the downshift flag FlgD, the turbine rotation Nt, and the transmission output shaft rotation No are read as signals determined by the shift control. In process 57, the output shaft rotation ratio gr (n) of the current transmission is calculated using Nt and No. In process 58, Nt is differentiated to calculate the current turbine rotational speed change rate Nta (n). Further, in process 59, No is differentiated to calculate the current transmission output shaft rotational speed change rate Noa (n). In the process 60, a subroutine (described later) for detecting a rough road that is considered to adversely affect the control using the transmission output shaft rotation change rate is executed. If it is determined that the road is a bad road, FlgC becomes 1, so that the process 61 proceeds to the processes 62 and 63 and returns. If it is not a rough road, the process proceeds to step 64 to determine whether an upshift signal has been issued. In the case of yes, the process proceeds to processing 65, and it is determined whether or not the flag FlgUC for determining whether or not the drive shaft torque correction control at the time of upshift is being executed is 1. Since the initial value is 0, the process proceeds to process 66. In the process 66, the previous turbine rotation speed change rate Nta (n-1) and Nta (n) obtained in the process 62 are compared, and if it becomes the above, the low gear side clutch is switched to the high gear as described in FIG. It is determined that the clutch is switched to the clutch on the side, and the correction control start flag of processing 67 is set to 1. In response to this, engine torque control described later is executed. Then, processing 65 and 67 are executed until the engine torque control flag FlgU at the time of upshifting becomes 0 in processing 64. The flag FlgU is rewritten to 0 in an engine torque control flowchart described later. If the result of processing 64 is no, the flag FlgUC is set to 0 in processing 68 and the processing proceeds to processing 69. In process 69, it is determined whether or not a downshift signal is output. In the case of yes, the process proceeds to processing 70 and it is determined whether or not the flag FlgDC for determining whether or not the drive shaft torque correction control at the time of downshift is being executed is 1. Since the initial value is 0, processing 71 proceeds. In process 71, it is determined whether or not the current input / output shaft rotation ratio gr (n) is equal to or greater than the previous rotation ratio gr (n-1). This is for discriminating the rising characteristic at the initial stage of downshift signal generation and the characteristic of clutch switching timing. If yes in process 71, the process proceeds to process 72, and the previous transmission output shaft rotational speed change rate Noa (n-1) obtained in process 63 is compared with Noa (n). In the case described above, it is determined that the high gear side clutch is switched to the low gear side clutch as described with reference to FIG. 4, and the correction control start flag FlgDC in step 73 is set to 1. Similarly to the upshift, engine torque control described later is executed, and processes 70 and 73 are executed until the engine torque control flag FlgD during downshift becomes 0 in process 69. The flag FlgD is also rewritten to 0 in the engine torque control flowchart described later. When it becomes 0, the process proceeds from the process 69 to the process 74, FlgDC is set to 0, the process proceeds to the processes 62 and 63, and the process returns. Further, a torque sensor is attached before and after the speed change mechanism using the relationship that the torque and the rotational speed change rate are proportional, and the clutch switching timing can be detected by detecting the torque change before and after the mechanism.
[0019]
FIGS. 7A and 7B are control flowcharts of drive shaft torque correction control. First, in process 75, the FlgUC, FlgDC, engine rotation Ne, Nt, No, and gr (n) are read. In process 76, torque converter input / output shaft rotation ratio e is calculated using Nt and Ne. In the process 77, a function of the rotation ratio e (actually, a torque converter characteristic table is generally searched) f₁ And f₂ Thus, a torque converter pump capacity coefficient c and a torque ratio t are obtained respectively. In the process 78, the turbine torque Tt is calculated using the calculated c and t and the read Ne. This Tt may be a signal from a torque sensor. Next, in process 79, it is determined whether or not the drive shaft torque correction control start flag FlgUC at the time of upshift shown in FIG. In the case of yes, the process f proceeds to step 80, and the function f of the calculated Tt and the previous transmission mechanism input / output shaft rotation ratio gr (n-1) (low gear side rotation ratio)._Three To calculate the target torque Ttar. In the process 81, the function f of the high gear side rotation ratio using the current transmission mechanism input / output shaft rotation ratio gr (n)._Four Thus, the torque transmission ratio td is calculated. In step 82, the transmission output shaft torque Tou during upshifting is calculated using the calculated Tt and td. In process 83, it is determined whether or not the torque feedback control start flag FlgA is 1. Since the initial value is 0, the process proceeds to process 84. In the initial stage of the drive shaft torque correction control, timer control is performed because the controllability is better when the engine torque is uniformly reduced than the target torque control. Thereafter, torque feedback control is executed. Processing 84 to 88 is timer control. In process 84, the timer control time K₂ Determine if it has passed. In the case of no, 1 is added to Timer1 in process 85, and the uniform ignition timing retard amount K is determined in process 86._Three Is input to the corrected ignition timing Δadv. In step 87, the ignition timing ADV is calculated and output in step 88. If the timer control is ended in the process 84, that is, if yes, the FlgA is set to 1 in the process 80, the Timer is set to 0 in the process 90, and the process proceeds to the process 90. Thereafter, the process jumps from the process 83 to the process 91 until the torque feedback control is completed. In the process 91, a deviation ΔT between the calculated actual transmission output shaft torque Tou and the target torque Ttar is calculated, and in a process 92, it is determined whether or not ΔT is smaller than 0. If no, the process proceeds to step 93 and the function f of ΔT_Five Is used to calculate the corrected ignition timing Δadv. This is the ignition timing control of torque feedback. If the answer is yes in process 92, the process proceeds to process 94 and the timer Timer3 is set to K.₇ Determine whether or not. This is executed in order to determine whether or not the drive shaft torque at the time of upshift is smaller than the target torque and the shift is completed. If no, Timer 95 is incremented in process 95 and feedback control is continued in process 93. If yes, FlgU, FlgD, FlgA, FlgB, and Δadv are set to 0 in steps 96 to 100, and the flow proceeds to step 87. This completes the torque correction control during the upshift.
[0020]
If NO in process 79, the process proceeds to process 101 to determine whether the torque control start flag FlgDC during downshift is 1 or not. In the case of no, Δadv is set to 0 in process 102 and the process proceeds to process 87. In the case of yes, the process f proceeds to processing 103 and the function f of the calculated Tt and the previous transmission mechanism input / output shaft rotation ratio gr (n-1) (low gear side rotation ratio)._Three To calculate the target torque Ttar. In process 104, the transmission output shaft speed change rate Noa and the torque conversion constant K_Four Thus, the transmission output shaft torque Tod at the time of downshift is calculated. This Tod may be a signal from a torque sensor attached to the transmission output shaft. In the process 105, it is determined whether or not the downshift torque feedback control start flag FlgB is 1. Since the initial value is 0, the process proceeds to processing 106. In the initial stage of the drive shaft torque correction control, timer control is performed because the controllability is better when the engine torque is uniformly reduced than the target torque control. Thereafter, torque feedback control is executed. Processing 106 to 110 is timer control. In process 106, the timer control time K_Five Determine if it has passed. In the case of no, 1 is added to Timer2 in the process 107, and the uniform ignition timing retard amount K is processed in the process 108.₆ Is input to the corrected ignition timing Δadv. In step 87, the ignition timing ADV is calculated and output in step 88. In the case where the timer control is ended in the process 106, that is, yes, the FlgB is set to 1 in the process 109, the Timer2 is set to 0 in the process 110, and the process proceeds to the process 111. Thereafter, the process jumps from the process 105 to the process 111 until the torque feedback control is completed. In the process 111, a deviation ΔT between the calculated actual transmission output shaft torque Tod and the target torque Ttar is calculated, and thereafter, torque feedback control similar to the upshift is executed.
[0021]
FIG. 8 is a subroutine flowchart for detecting a rough road. In process 112, the timer Timer4 is set to the rough road determination period K.₈ It is determined whether or not the above has been reached. Since the initial value is 0, the process proceeds to process 113, Timer 4 is incremented, and the process proceeds to process 114. In the process 114, the positive threshold value K set by the current transmission output shaft rotational speed change rate Noa (n) is set.₉ Judge whether it is above. If yes, the process proceeds to process 115, the rough road determination coefficient x is incremented, and the process proceeds to process 116. On the other hand, if the result of the process 114 is no, the process proceeds to a process 117 where the current transmission output shaft rotational speed change rate Noa (n) is set to the negative threshold K._TenDetermine if: If yes, the process proceeds to process 118, the rough road determination coefficient y is incremented, and the process proceeds to process 116. In the process 116, the x and y are respectively threshold coefficients K.₁₁ And K₁₂ Judge whether it is above. In both cases, Noa (n) is greatly changed positively or negatively, that is, it is determined that the road is a rough road, the process proceeds to step 119, 1 is input to the rough road determination flag FlgC, and the process returns to the main routine of FIG. If it is not determined in step 116 that the road is a bad road, the process proceeds to step 120, where it is determined whether FlgC is 1. In the case of yes, it is determined that the rough road still continues, and the process proceeds to processing 119. If no, it means that the road is being judged as bad. If the answer is yes in process 112, the rough road determination time ends, and in processes 121, 122, 123, and 124, 0 is input to x, y, Timer 4, and FlgC, respectively, and the process returns.
[0022]
FIG. 9 is a time chart of conventional torque control during upshift, and FIG. 10 is a time chart of torque control during upshift according to the present invention. Conventionally, t_Three The speed change mechanism input / output shaft rotation ratio Nt / No was used in spite of the change in turbine rotation at the time of, so the change in the rotation ratio did not appear remarkably and the point of the black circle a is the start timing of engine torque control. It was. Therefore, the transmission output shaft torque decreases from the middle of the shift as shown by the broken line, and is not very effective in suppressing the shift shock. Further, the shift completion grasp timing b is also obtained by matching in consideration of the engine torque control end and the variation of the transmission output shaft torque.
[0023]
On the other hand, in the present invention shown in FIG. 10, the clutch switching timing t is surely obtained in either the turbine torque or the turbine rotational speed change rate._Three Can be recognized. In addition, by executing the control shown in FIGS. 6 and 7, the transmission output shaft torque (broken line) is smoothly changed, and the shift shock is considerably suppressed. The flags and constants shown in FIGS. 6 and 7 change as shown in FIG. The target torque is also used for recognizing the end of a shift. However, since the output shaft torque fluctuation varies for each shift, it is necessary to change the inclination for each shift.
[0024]
FIG. 11 is a time chart of conventional torque control during downshift, and FIG. 12 is a time chart of torque control during downshift according to the present invention. Conventionally, in order to suppress the fluctuation of the transmission output shaft torque after the clutch switching timing a, the point a is grasped using the transmission mechanism input / output shaft rotation ratio. Since the rotation ratio settles constant after the clutch is switched, the relationship between the clutch switching timing and the rotation ratio is obtained by matching by experiment to grasp the switching timing a. Further, it is necessary to store matching data for each shift, and the ROM capacity is also increased.
[0025]
On the other hand, in the present invention shown in FIG. 12, it is possible to reliably recognize the clutch switching timing a in either the transmission output shaft torque or the transmission output shaft rotational speed change rate. In addition, by executing the control shown in FIGS. 6 and 7, the transmission output shaft torque (broken line) is smoothly changed, and the shift shock is considerably suppressed. The flags and constants shown in FIGS. 6 and 7 change as shown in FIG. The target torque is also used for recognizing the end of a shift. However, since the output shaft torque fluctuation varies for each shift, it is necessary to change the inclination for each shift.
[0026]
FIG. 13 is a time chart when a rough road is detected. K₉ Is the positive threshold, K_TenIs the negative threshold. Rough road detection time K₈ K during₉ And K_TenWhen the value exceeding the number exceeds the number of bad road judgments, the rough road judgment flag FlgC becomes 1. The rough road determination flag FlgC becomes 0 when the number of bad road determinations is less than or equal to.
[0027]
FIG. 14 is an upshift transmission output shaft torque estimation time chart, and FIG. 15 is a downshift transmission output shaft torque estimation time chart. In FIG. 14, the turbine torque Tt calculated using the torque converter input / output shaft speed and the torque converter characteristics, or the turbine torque Tt obtained by the torque sensor attached to the torque converter output shaft and the torque at the time of clutch switching. By multiplying the torque transmission ratio td at which the transmission state changes from the low gear side to the high gear side, it is possible to estimate the transmission output shaft torque Tou during the upshift.
[0028]
In FIG. 15, a rotational speed change rate Noa obtained from the transmission output shaft rotational speed and a torque conversion constant K for converting the acceleration into torque._Four Is multiplied by the transmission output shaft torque Tod during downshifting. By applying the transmission output shaft torque estimation during shifting, the shift shock can be greatly reduced.
[0029]
In addition, the drive shaft torque correction control at the time of shifting described above is ignition timing control. However, a system with good exhaust performance can be realized by using air amount control or clutch engagement pressure control by an electronically controlled throttle.
[0030]
FIG. 16 is a time chart for shock reduction control during downshifting. As described above, the transmission output shaft rotational speed change rate Noa is substantially proportional to the transmission output shaft torque. This is a case where there is almost no torque fluctuation between the tire and the transmission output shaft, that is, there is no shaft vibration. In this case, the Noa signal substantially matches the signal of the acceleration sensor attached to the vehicle body. Therefore, it is possible to grasp when the clutch is engaged by the method shown in FIG. On the other hand, the torque fluctuation between the tire and the transmission output shaft, that is, the case where shaft vibration occurs is shown in the transmission output shaft rotational speed change rate Noa2. This signal occurs when there is a long shaft between the tire and the transmission, such as a rear drive. Therefore, when the clutch engagement timing is detected using this Noa2 signal, it is necessary to grasp the rapid rising point (black circle) of Noa2. By reducing the engine torque at this timing, the shock at the time of downshift can be suppressed as indicated by a broken line. Further, for the engine torque reduction control such as ignition timing retard, the signal waveform of Noa2 can be used to match the change of the Noa2 signal. Thus, it is not necessary to store the engine torque reduction amount and time in a table, and the ROM (Read Only Memory) capacity can be reduced.
[0031]
FIG. 17 is a flowchart of shock reduction control when Noa2 in FIG. 16 is used. First, in the process 130, the downshift start flag FlgD and the variable machine output shaft rotational speed No2 when the shaft vibration occurs are read as signals determined by the shift control. In the process 131, the change rate Noa2 of No2 is calculated. In process 132, it is determined whether FlgD has become 1, that is, whether a downshift signal has been generated. In the case of no, the process proceeds to process 133, 0 is input to the corrected ignition timing Δadv, and the process proceeds to process 134. Then, the retard amount Δadv is subtracted from the actual reference ignition timing ADV and output in processing 135. If yes in process 132, the process proceeds to process 136, and it is determined whether the downshift engine torque reduction control start flag FlgDCS is 1. If no, the process proceeds to process 137, where Noa2 is a downshift engine torque reduction control start constant k._TenJudge whether it is above. If no, the process 133 proceeds. If yes, the process proceeds to process 138, and 1 is input to the FlgDCS. Then, in process 139, Δadv is changed to a function f of Noa2._TenThe process proceeds to the process 134. This time is point (a) in FIG. When FlgDCS is 1 in process 136, the process proceeds to process 140, and Noa2 is a downshift engine torque reduction control termination constant k.₁₁It is determined whether or not it is below, that is, whether or not engine torque is being reduced. If the engine torque is being reduced, that is, if no, the routine proceeds to processing 136. In the case of completion, ie, yes, the process proceeds to processes 141, 142, and 143, and 0 is input to FlgD, FlgDCS, and Δadv, respectively, and the process proceeds to process 134. As a result, the downshift shock reduction control using the Noa2 signal can be realized accurately and without cost increase.
[0032]
FIG. 18 is a time chart for shock reduction control during upshifting. Also in the upshift, signal waveforms of Noa and Noa2 exist as in FIG. Noa shows a waveform similar to that of the output shaft torque, but Noa2 generates a large vibration as shown in FIG. Although the clutch engagement timing to the upshift side is slightly delayed, it can be almost grasped by the fall of Noa2, and engine torque reduction control is started from this timing. The control target value at this time is obtained by using Noa2 when the upshift signal (FlgU) is generated. Then, the engine torque is controlled by the deviation between the target value and the actual Noa2 to suppress the shock. Thereby, the torque characteristic at the time of upshift like a broken line is acquired.
[0033]
FIG. 19 is a shock reduction control flowchart when Noa2 of FIG. 17 is used. First, in process 144, the upshift start flag FlgU and the transmission output shaft rotational speed No2 when the shaft vibration occurs are read as signals determined by the shift control. In the process 145, the change rate Noa2 of No2 is calculated. In the process 146, it is determined whether or not the process avoidance flag FlgL for latching the Noa2 signal when the upshift start signal is generated becomes 1. If no, the process proceeds to process 147, and it is determined whether FlgU has become 1, that is, whether an upshift signal has been generated. In the case of no, the process proceeds to process 148, and 0 is input to the corrected ignition timing Δadv, and the process proceeds to process 149. Then, the retard amount Δavd is subtracted from the actual reference ignition timing AVD and output in processing 150. If yes in process 147, the process proceeds to process 151, and the value of Noa2 is set to k.₁₂To latch. In step 152, 1 is input to FlgL. In process 153, the timer Timer for determining the engine torque reduction control end time is set to the end time constant k.₁₃Judge whether it is above. If no, the process proceeds to process 154 and increments Timer. Then, the process proceeds to process 155, where Noa2 is the target value setting constant k.₁₂Function f₁₁It is determined whether or not the engine torque control target value obtained in step 1 is exceeded. Here, only the engine torque reduction control is shown because the ignition timing retard is used for engine torque control. For example, when a throttle valve control system is added, engine torque increase / decrease control is possible. If the result of process 155 is no, the process proceeds to process 148. If yes, the process proceeds to process 156 and Δadv is changed to the function f of Noa2._TenThe process proceeds to processing 149. This time is point (a) in FIG. In process 153, Timer is k₁₃In the above case, it is determined that the engine torque control at the time of upshifting is finished, and the process proceeds to processes 157, 158, 159 and 160, and 0 is input to FlgL, FlgU, Δadv and Timer, respectively, and the process proceeds to process 149. As a result, the upshift shock reduction control using the Noa2 signal can be realized accurately and without cost increase.
[0034]
【The invention's effect】
  Drive shaft torque correction control can be executed at appropriate timing, and shift shock can be reduced.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of the present invention.
FIG. 2 is a schematic configuration around an engine and an automatic transmission.
FIG. 3 is a hardware configuration of a control controller.
FIG. 4 shows shift characteristics during upshifting.
FIG. 5 shows shift characteristics during downshifting.
FIG. 6 is a flowchart of an embodiment of the present invention.
FIG. 7 is a control flowchart of drive shaft torque correction control.
FIG. 8 is a subroutine flowchart of bad road detection.
FIG. 9 is a time chart of conventional torque control during upshifting.
FIG. 10 is a time chart of torque control during upshift according to the present invention.
FIG. 11 is a time chart of conventional torque control during downshifting.
FIG. 12 is a time chart of torque control during downshift according to the present invention.
FIG. 13 is a time chart when a rough road is detected.
FIG. 14 is a transmission output shaft torque estimation time chart during upshifting.
FIG. 15 is a transmission output shaft torque estimation time chart during downshifting.
FIG. 16 is a time chart for shock reduction control during downshifting.
FIG. 17 is a downshift shock reduction control flowchart;
FIG. 18 is a time chart for shock reduction control during upshifting.
FIG. 19 is a shock reduction control flowchart during upshifting.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Pre-transmission-mechanism signal detection means, 2 ... Post-transmission-mechanism signal detection means, 3 ... Upshift clutch switching timing signal recognition means, 4 ... Upshift clutch switching signal storage means, 5 ... Downshift clutch switching timing Signal recognition means, 6 ... Signal storage means before clutch change at downshift, 7 ... Drive shaft torque correction control start signal output means at upshift, 8 ... Engine torque control means, 9 ... Drive shaft torque correction control start signal at downshift Output means.

Claims (2)

A post-transmission-mechanism signal detection means for detecting the rotational speed change rate of the output shaft of the automatic transmission;
A pre-transmission-mechanism signal detection means for detecting the rotational speed change rate of the output shaft of the torque converter;
Rough road determination means for determining that the vehicle is traveling on a rough road based on the post-shift mechanism signal detection means;
Based on the speed change mechanism before signal detecting means, based on the means and the transmission mechanism after the signal detecting means for detecting a timing switching clutch during upshifting of the automatic transmission, a clutch during downshifting of the automatic transmission Shifting timing detection means having means for detecting the switching timing of
From the first engine torque control mode for correcting the engine torque output to the output shaft of the automatic transmission mechanism based on the shift timing detection means when the rough road determination means determines that the vehicle is traveling on a rough road. the control device for an automatic transmission and a switching means for switching to a second engine torque control mode without correcting the engine torque. Detects the rate of change in the rotational speed of the output shaft of the automatic transmission,
Detect the rate of change of the rotation speed of the output shaft of the torque converter,
Based on the detected value of the rotational speed change rate, it is determined that the road is running on a rough road,
Based on the detection result of the rotational speed change rate of the output shaft of the torque converter , the clutch switching timing at the time of upshift of the automatic transmission is detected, and the detection result of the rotational speed change rate of the output shaft of the automatic transmission is detected. Based on the detection time of clutch switching at the time of downshift of the automatic transmission based on,
From the first engine torque control mode for correcting the engine torque output to the output shaft of the automatic transmission mechanism based on the detection result of the shift timing when the rough road determination determines that the vehicle is traveling on a rough road, A method for controlling an automatic transmission that switches to a second engine torque control mode in which engine torque is not corrected.

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