JP4139654B2 - Control device for automatic transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for performing automatic shift control in an automatic transmission. More specifically, the present invention supplies engagement control hydraulic pressure to a friction engagement element (for example, a friction clutch, a brake, etc.) to set a desired shift stage. The present invention relates to a device that performs shift control.
[0002]
[Prior art]
An automatic transmission generally includes a plurality of power transmission paths (a plurality of power transmission gear trains) and a plurality of friction engagement elements (friction clutches, brakes, etc.), and travels such as engine throttle opening, traveling vehicle speed, etc. The friction engagement element is selectively engaged in accordance with the state, and the power transmission path is switched and selected to perform shift control. As a friction engagement element used for such shift control, a hydraulically operated element that is engaged by hydraulic pressure is generally known. For example, there is a device disclosed in Japanese Patent Laid-Open No. 10-184887. .
[0003]
By the way, when the shift control is performed using the hydraulically operated friction engagement element as described above, the engagement control hydraulic pressure supplied to the friction engagement element is a condition for determining the transmission torque, and the engagement control hydraulic pressure is transmitted to the transmission torque. Therefore, it is necessary to perform finely-tuned control according to the situation. For this purpose, it is important to accurately calculate the output torque of the engine, and various proposals have conventionally been made in this regard. For example, in the device disclosed in Japanese Patent Application Laid-Open No. 2001-165291 relating to the application of the present applicant, the input torque of the transmission is calculated, and the engagement control hydraulic pressure of the friction engagement element is appropriately set according to the calculated input torque. Is disclosed.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-153259 [Patent Document 2]
JP 2001-165290 A [Patent Document 3]
JP 2001-165291 A [Patent Document 4]
JP 2001-165303 A [Patent Document 5]
Japanese Patent Laid-Open No. 2002-130454
[Problems to be solved by the invention]
Thus, when calculating the transmission input torque, if this torque calculation is inaccurate, the shift control will be inaccurate, and therefore it is necessary to calculate the input torque with the highest possible accuracy. The input torque of the transmission is determined most depending on the engine output torque, but the valve operating characteristics such as the opening / closing timing of the engine intake / exhaust valve, the opening time, the valve lift amount (that is, the valve opening amount) are switched. In an engine having a variable valve valve timing mechanism that can be set, the engine output characteristics change according to the switching operation of the variable valve timing mechanism. There is a problem that variations occur.
[0006]
In particular, in an engine equipped with a variable valve timing mechanism, a hysteresis region is set so that the switching operation timing of the variable valve timing mechanism differs for each switching direction, thereby preventing frequent switching operations within this region. Therefore, there is a problem that it is difficult to calculate the engine output torque in this hysteresis region. For example, the timing (engine speed) at which the low speed side valve timing characteristic set in the low speed range is switched to the high speed side valve timing characteristic set at the high speed range, and the timing at which the high speed side valve timing characteristic is switched to the low speed side valve timing characteristic. Are provided with hysteresis. For this reason, if the engine output torque is calculated by changing the engine output torque map in the low-speed side valve timing characteristics and the engine output torque map in the high-speed side valve timing characteristics, the map is changed according to the switching operation of the variable valve timing mechanism. There is a problem that the calculated engine output torque changes suddenly when the switch is carried out, and smooth shift control cannot be performed.
[0007]
The present invention has been made in view of such problems, and is configured so that the output of an engine having a variable valve timing mechanism can be smoothly shifted and transmitted to a wheel without being affected by the operation of the variable valve timing mechanism. An object of the present invention is to provide a control device for an automatic transmission.
[0008]
[Means for Solving the Problems]
In order to achieve such an object, in the present invention, a plurality of power transmission paths (for example, first to fifth gear trains in the embodiment) and a plurality of hydraulically operated friction engagement elements (for example, 1 in the embodiments). Speed to fifth speed clutches 11 to 15), and selectively engages a plurality of friction engagement elements using hydraulic pressure according to the traveling state to select one of the power transmission paths and The automatic transmission is configured to set and shift the output rotation of the engine based on the thus set shift speed and transmit it to the wheels, and the control device performs a predetermined shift according to the shift instruction. In this way, hydraulic pressure supply control means (for example, the hydraulic pressure control valve HCV in the embodiment) for controlling the supply of engagement control hydraulic pressure to the friction engagement elements, engine torque calculation means for calculating engine output torque, A variable valve timing mechanism capable of switching the operating characteristics of at least one of the gin intake and exhaust valves, and a transmission for calculating a transmission input torque input to the transmission from the engine output torque calculated by the engine torque calculation means Input torque calculating means. The engine torque calculation means calculates the pre-switching engine output torque corresponding to the pre-switching operation characteristics and the post-switching engine output torque corresponding to the pre-switching operation characteristics during the switching operation of the variable valve timing mechanism. A corrected engine output torque is calculated by correcting the engine output torque so that it continuously changes from the start of the switching operation to the post-switching engine output torque during the switching elapsed time, and the transmission input torque calculating means is calculated by the engine torque calculating means. When transmission input torque to be input to the transmission is calculated from the calculated engine correction output torque, and supply control of engagement control hydraulic pressure for shifting to the friction engagement element is performed by the hydraulic supply control means according to the shift instruction Further, based on the transmission input torque calculated by the transmission input torque calculating means, the engagement control hydraulic pressure for shifting is calculated. It is constant.

[0010]
According to the automatic transmission control apparatus of the present invention having such a configuration, when the variable valve timing mechanism is switched, the engine output torque before switching is smoothly changed from the engine output torque after switching to the engine output torque after switching. Based on the corrected engine output torque corrected to, the engagement control oil pressure that is controlled to be supplied by the oil pressure supply control means is set and a shift is performed, so the calculated engine output that is calculated with the switching operation of the variable valve timing mechanism Torque does not change abruptly, and smooth and smooth shift control can be performed.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. First, FIG. 1 schematically shows the overall configuration of an automatic transmission and its control device according to the present invention. An automatic transmission TM (hereinafter referred to as a transmission) TM whose speed is controlled by this control device is mounted on a vehicle (not shown), and has a parallel shaft type transmission mechanism of five forward speeds and one reverse speed. Composed.
[0012]
The transmission TM includes a main shaft (input shaft) MS connected to a crankshaft ES of an internal combustion engine (hereinafter referred to as “engine”) ENG via a torque converter TC having a lockup mechanism LC, and a parallel to the main shaft MS. And a countershaft CS that extends and is connected to the main shaft MS via a plurality of gear trains.
[0013]
On the main shaft MS, a first speed drive gear 11 is rotatably disposed, a second speed drive gear 12 is rotatably disposed, a third speed drive gear 13 is coupled, and a fourth speed drive gear 14 is rotated. A 5-speed drive gear 15 is coupled and disposed, and a reverse drive gear 16 is formed integrally with the 4-speed drive gear 14 and is rotatably disposed.
[0014]
The counter shaft CS has a first speed driven gear 21 meshed with the first speed drive gear 11, a second speed driven gear 22 meshed with the second speed drive gear 12, a third speed driven gear 23 meshed with the third speed drive gear 13, and a fourth speed. A fourth speed driven gear 24 meshed with the drive gear 14, a fifth speed driven gear 25 meshed with the fifth speed drive gear 15, and a reverse driven gear 26 meshed with the reverse drive gear 16 via the reverse idler gear 17 are provided. . The first speed driven gear 21 is coupled to the counter shaft CS, the second speed driven gear 22 is coupled to the counter shaft CS, the third speed driven gear 23 is rotatably disposed, and the fourth speed driven gear 24 is The fifth speed driven gear 25 is rotatably arranged, and the reverse driven gear 26 is rotatably arranged.
[0015]
The main shaft MS is further coupled to the main shaft MS with a first speed drive gear 11, a second speed drive gear 12 and a fourth speed drive gear 14 (and a reverse drive gear 16 integrated therewith) disposed so as to be relatively rotatable. A first speed hydraulic clutch C1, a second speed hydraulic clutch C2 and a 4-R clutch C4 are disposed. The countershaft CS is provided with a third-speed hydraulic clutch C3 and a fifth-speed hydraulic clutch C5 that couple the rotatable third-speed driven gear 23 and the fifth-speed driven gear 25 to the countershaft CS, respectively.
[0016]
Further, a dog-tooth mechanism 28 is disposed between the fourth-speed driven gear 24 and the reverse driven gear 26 on the counter shaft CS, and the selector 28a is moved in the axial direction by a servo actuator (not shown) so that the fourth-speed driven gear 24 is moved. The driven gear 24 can be coupled to the countershaft CS, and the reverse driven gear 26 can be coupled to the countershaft CS.
[0017]
In the transmission TM configured as described above, when the first-speed clutch 11 is engaged and the first-speed drive gear 11 is coupled to the main shaft MS, the rotation of the main shaft MS causes the first-speed drive gear 11 and the first-speed driven gear 21 to rotate. A first gear to be transmitted to the countershaft CS through the first gear train is set. Further, when the second-speed clutch 12 is engaged and the second-speed drive gear 12 is coupled to the main shaft MS, the rotation of the main shaft MS is performed via the second-speed gear train including the second-speed drive gear 12 and the second-speed driven gear 22. Thus, the second speed transmitted to the countershaft CS is set. Similarly, when the third-speed clutch 13 is engaged and the third-speed driven gear 23 is coupled to the countershaft CS, the rotation of the main shaft MS is transmitted through the third-speed gear train including the third-speed drive gear 13 and the third-speed driven gear 23. Thus, the third speed transmitted to the countershaft CS is set.
[0018]
On the other hand, when the 4-speed drive gear 14 and the reverse drive gear 16 integrally formed by engaging the 4-R clutch C4 are coupled to the main shaft MS, the 4-speed driven where the rotation of the main shaft MS meshes with these gears. It is transmitted to the gear 24 and the reverse driven gear 26. However, the 4-speed driven gear 24 and the reverse driven gear 26 are rotatably disposed on the countershaft CS, and are selectively engaged with and disengaged from the countershaft CS according to the operation of the dog tooth clutch 28. That is, when the selector 28a of the dog-tooth clutch 28 is moved to the left in the drawing by a servo actuator (not shown) to couple the 4-speed driven gear 24 to the countershaft CS, the rotation of the main shaft MS is driven by the 4-speed drive gear 14 and the 4-speed driven. A fourth speed stage that is transmitted to the countershaft CS via a fourth speed gear train composed of the gear 24 is set. When the selector 28a of the dog-tooth clutch 28 is moved to the right in the drawing to couple the reverse driven gear 26 to the counter shaft CS, the rotation of the main shaft MS is caused by the reverse drive gear 16, the reverse idler gear 17 and the reverse driven gear 26. The reverse speed transmitted to the countershaft CS via the reverse gear train is set.
[0019]
As described above, the first speed, the fifth speed, the fourth speed, the 4-R and the fifth speed clutches C1 to C5 and the movement control of the selector 28a of the dog-tooth mechanism 28 by the servo actuator are used. And the reverse stage is set. Engagement control of these 1st speed, 2nd speed, 3rd speed, 4-R and 5th speed clutches C1 to C5 and operation control of the servo actuator are controlled by receiving hydraulic oil supplied from the hydraulic control valve HCV. The operation control of the hydraulic control valve HCV is performed based on a control signal from the control unit ECU.
[0020]
As described above, the first to fifth gears or the reverse gear is set, and the rotation of the main shaft MS is transmitted to the countershaft CS via each gear train. The rotation of the counter shaft CS is transmitted to the differential mechanism DF via the final drive gear 31 and the final driven gear 32, and then to the left and right drive wheels W, W of the vehicle (not shown) via the left and right axle shafts 33, 33. Is transmitted to.
[0021]
A shift lever device 40 is provided in the vicinity of the floor of the vehicle driver's seat (not shown), and eight kinds of position ranges, P, R, N, D5, D4, D3, 2, 1 are set by the driver's shift lever operation. Either one is selected. A position sensor 41 for detecting the shift lever operation position is provided, and a position range signal PRS indicating which position range is selected in accordance with the shift lever operation is sent from the sensor 41 to the control unit ECU.
[0022]
In this apparatus, a throttle valve opening TH for detecting the throttle valve opening TH of the engine ENG, an intake negative pressure PBA and a cooling water temperature TWE, an intake negative pressure sensor 52 and a cooling water temperature sensor 53 are arranged as shown in the figure. The detection signals TH, PBA and TWE are sent to the control unit ECU. Engine rotation sensor 54 that detects engine output rotation speed NE (that is, torque converter input rotation speed), main rotation sensor 55 that detects rotation speed NM of main shaft MS, and counter rotation sensor that detects rotation speed NC of countershaft CS 56, a vehicle speed sensor 58 for detecting the rotational speed of the final driven gear 32 to detect the vehicle speed V is arranged as shown in the figure, and each detection signal NE, NM, NC, V is sent to the control unit ECU.
[0023]
The hydraulic control valve HCV is provided with an oil temperature sensor 57 for detecting the hydraulic oil temperature TTM supplied to each of the clutches C1 to C4, and the detection signal TTM is sent to the control unit ECU. A brake sensor 59 for detecting the depression of the brake pedal, that is, the brake operation is also provided, and the detection signal BS is also sent to the control unit ECU.
[0024]
The engine ENG is provided with a variable valve timing mechanism for switching and setting valve operating characteristics such as opening / closing timing, release time and valve lift amount of the engine intake / exhaust valve, and a valve timing switching operation detector for detecting the switching operation. 61 is attached to the engine ENG. A detection signal VTS detected by the valve timing switching operation detector 61 is also sent to the control unit ECU. In this embodiment, a case will be described in which a variable valve timing mechanism can be switched between a low-speed valve timing characteristic (LVT characteristic) and a high-speed valve timing characteristic (HVT characteristic) in two stages. The engine ENG is provided with an exhaust gas recirculator (EGR device) for exhaust gas purification. An EGR operation detector 62 for detecting the operation amount of the exhaust gas recirculator is attached to the engine ENG, and an operation signal (EGR signal) EGR detected by the EGR operation detector 62 is also sent to the control unit ECU. .
[0025]
The control unit ECU controls the operation of the hydraulic control valve HCV based on the detection signals sent from these sensors 41, 51 to 59, 61, 62, and the 1st speed, 2nd speed, 3rd speed, 4-R The automatic shift control is performed by controlling the engagement of the fifth speed clutches C1 to C5 and the operation control of the servo actuator. Note that the hydraulic control valve HCV is provided with a linear solenoid valve (not shown) for setting the pressure regulation of the engagement control hydraulic pressure supplied to each of the clutches C1 to C5, and a control signal (from the control unit ECU) The operation of the linear solenoid valve is controlled based on the drive current), and the engagement control hydraulic pressure supplied to each of the clutches C1 to C5 is controlled.
[0026]
The automatic shift control performed by the control unit ECU in this way will be described below. FIG. 2 is a main flow chart showing the operation of the automatic transmission control main program, and the operation content will be described in combination with the sub-flowcharts shown in FIG. This program is repeatedly executed at predetermined time intervals, for example, every 10 msec.
[0027]
In the control shown in the main flowchart of FIG. 2, first, various parameters are calculated in step S1, the process proceeds to step S2 to set a shift mode, and in step S3, engagement control of the lockup clutch LC of the torque converter TC is performed. In S4, shift control is performed in which the clutches C1 to C5 and the dog-tooth mechanism 28 are operated to perform automatic gear shifting.
[0028]
As shown in FIG. 3, the parameter calculation step S1 constituting step S1 includes step S11 for reading various detection values and step S12 for calculating the residual oil amount (Qc) in each of the clutches C1 to C5. In step S11, the above-described position sensor 41, throttle opening sensor 51, intake negative pressure sensor 52, cooling water temperature sensor 53, engine rotation sensor 54, main rotation sensor 55, counter rotation sensor 56, oil temperature sensor 57, vehicle speed sensor. 58, a detection signal detected by a brake sensor 59, an EGR operation detector 61, a valve timing switching operation detector 62, etc., that is, a position range signal PRS indicating a position range selected by operating a shift lever, a throttle valve of the engine ENG Opening degree TH, intake negative pressure PBA, cooling water temperature TWE, engine output rotational speed NE, main shaft MS rotational speed NM, countershaft CS rotational speed NC, hydraulic oil temperature TTM supplied to each clutch C1 to C4, Indicates vehicle speed V, brake operation Rake signal BS, EGR operation signal indicating the EGR operation amount EGR, the detection signal such as valve timing signal VTS showing the variable valve timing characteristics is read.
[0029]
The contents of the clutch residual oil amount (Qc) estimation subflow in step S12 are shown in FIG. A plurality of clutches C1 to C5 are provided in the transmission, and a clutch residual oil amount Qc is calculated for each clutch. That is, the subflow of FIG. 4 exists for each clutch. In this sub-flow S12, first, in step S121, the clutch instruction oil pressure Pi for setting the clutch engagement control oil pressure is read. As described above, the clutch engagement control hydraulic pressure supplied to each of the clutches C1 to C5 for shift control is regulated by the linear solenoid valve in the hydraulic control valve HCV, and is instructed to control the operation of the linear solenoid valve. The hydraulic pressure to be applied is the clutch instruction hydraulic pressure Pi, which is a value corresponding to the drive current of the linear solenoid valve.
[0030]
Next, the process proceeds to step S122, and it is determined whether or not the clutch instruction oil pressure Pi exceeds the oil pressure value 1.6 Kgf / cm ² (= 156800 Pa) set as the first predetermined value Pi (1). The first predetermined value Pi (1) is the lowest hydraulic pressure that can be maintained in the state where the hydraulic oil is filled in the clutch with respect to the target clutch. If an engagement control hydraulic pressure lower than this hydraulic pressure is set, the first predetermined value Pi (1) The hydraulic oil begins to flow out. Note that both the first predetermined value Pi (1) and the second predetermined value Pi (2) described below are obtained and set in advance by experiments or the like. When it is determined in step S122 that Pi> 1.6 (Kgf / cm ² ) (YES), the hydraulic oil does not flow out. Therefore, in step S123, the clutch residual oil amount Qc = 100% (full oil amount). This subflow is finished by setting as.
[0031]
On the other hand, when it is determined in step S122 that Pi ≦ 1.6 (Kgf / cm ² ) (NO), the process proceeds to step S124, in which the clutch instruction oil pressure Pi is set as the second predetermined value Pi (2). Determine whether the value exceeds 0.6 Kgf / cm ² (= 58800 Pa). The second predetermined value Pi (2) is a hydraulic pressure that causes the hydraulic oil in the clutch to flow out until it becomes empty when the hydraulic pressure supplied to the clutch is set to this value, and is lower than the second predetermined value Pi (2). In the engagement control hydraulic pressure, the hydraulic oil in the clutch continues to flow out until it is empty. On the contrary, when the hydraulic pressure higher than the second predetermined value Pi (2) (and the hydraulic pressure lower than the first predetermined value Pi (1)) is set, the hydraulic oil in the clutch becomes a certain amount of residual oil from the full amount state. The oil flows out until the amount is generated, but when the oil amount reaches a certain level, the outflow from the clutch stops. This “some amount of oil” is referred to as a lower limit oil amount QL.
[0032]
If it is determined in step S124 that Pi> 0.6 (Kgf / cm ² ) (YES), the process proceeds to step S125, and the oil reduction rate ΔQd in the clutch under the clutch command oil pressure Pi at this time, that is, Calculate the oil spill rate from the clutch. This calculation will be described below.
[0033]
For this calculation, for each clutch, a command hydraulic pressure Pi as indicated by a solid line in FIG. 5 was given to the linear solenoid valve, and the change in the clutch hydraulic pressure was measured. As shown in the figure, the command oil pressure is reduced to the low pressure command oil pressure Pi (B) for a predetermined time T1 from the state in which the high pressure command oil pressure Pi (A) is supplied, and then again the high pressure command oil pressure Pi (A). The command oil pressure Pi is returned to. The result of measuring the actual clutch oil pressure Pac actually generated in the target clutch when such an instruction oil pressure Pi is given is indicated by a broken line in the figure. Since the oil in the clutch flows out while decreasing to the low pressure command oil pressure Pi (B), the actual clutch oil pressure Pac gradually increases from the time when the command oil pressure Pi is returned to the high pressure command oil pressure Pi (A). Ascend to (A). At this time, the elapsed time T2 required for the actual clutch hydraulic pressure Pac to rise to the high pressure command hydraulic pressure Pi (A) is considered to be the time required to fill the clutch with oil, and the predetermined time T1 is changed. The elapsed time T2 was measured. The result is shown in FIG. 6, when T1 = 0, the clutch remains the full amount of oil, and as the predetermined time T1 becomes longer, the amount of oil in the clutch decreases and elapses as the predetermined time T1 increases. It is considered that the oil has flowed out until the amount of oil in the clutch reaches the amount of air oil where the time T2 does not change.
[0034]
It can be seen from the relationship of FIG. 6 that the oil reduction rate ΔQd (oil reduction amount per unit time) in the clutch is uniquely determined with respect to the clutch residual oil amount Qc. This relationship, that is, the relationship between the clutch residual oil amount Qc and the oil reduction rate ΔQd is as shown in FIG. However, the relationship of FIG. 6 is set in accordance with the temperature of the oil supplied to the clutch, the rotational speed of the clutch (which is proportional to the main shaft rotational speed NM), and the shift mode. In view of this, data related as shown in FIG. 7 is set and stored in advance as a plurality of maps corresponding to the oil temperature, the main shaft rotation speed NM, and the shift mode.
[0035]
In step S125, a map corresponding to the hydraulic oil temperature TTM, command oil pressure Pi, main shaft rotational speed NM, and shift mode detected in step S11 is selected from the plurality of maps stored in this manner. To read the oil reduction rate ΔQd corresponding to the current clutch residual oil amount Qc. Note that the initial value of the clutch residual oil amount Qc is set to the full oil amount (100%), and is subtracted and updated and stored as described below as time elapses. The oil reduction rate ΔQd is read based on the residual oil amount Qc.
[0036]
When the current oil reduction rate ΔQd is calculated in this way, the process proceeds to step S126 to calculate the lower limit oil amount QL. The lower limit oil amount QL changes according to the clutch command oil pressure Pi, and is calculated based on the following equation (1).
[0037]
[Expression 1]
QL (%) = (Pi−Pi (2)) / (Pi (1) −Pi (2)) × 100 (1)
[0038]
For example, when the clutch command oil pressure Pi = 1.1 (Kgf / cm ² ), the lower limit oil amount QL = (1.1−0.6) / (1.6−0.6) × 100 = 50 (% )
[0039]
When the lower limit oil amount QL is calculated in this way, the process proceeds to step S127, and it is determined whether or not the current clutch residual oil amount Qc> QL. When it is determined that Qc> QL (YES), the process proceeds to step S128, and the oil reduction rate ΔQd read as described above is subtracted (Qc−ΔQd) from the current clutch residual oil amount Qc. This is updated and stored as a new current clutch residual oil amount Qc, and this sub-flow is ended. This flow is repeatedly executed at a predetermined time interval (for example, 10 ms), and the oil reduction rate ΔQd is converted into a reduction rate at the repetition time interval, and the converted oil reduction rate is subtracted. On the other hand, when it is determined in step S127 that Qc ≦ QL (NO), step S128 is bypassed, the current clutch residual oil amount Qc is maintained as it is, and this subflow is ended.
[0040]
As can be seen from this, when the clutch instruction oil pressure Pi is between 1.6 (Kgf / cm ² ) and 0.6 (Kgf / cm ² ), the clutch residual oil amount Qc is set to the full oil amount (100%). ) To the lower limit oil amount QL based on the calculated oil reduction rate ΔQd, and after reaching the lower limit oil amount QL, the oil amount QL is retained and the clutch residual oil amount is estimated.
[0041]
When it is determined in step S124 that Pi ≦ 0.6 (Kgf / cm ² ) (NO), the process proceeds to step S129, and the oil decrease rate ΔQd in the target clutch under the clutch command oil pressure Pi at this time. Is calculated. This calculation is the same as in step S125 described above. In step S130, the oil reduction rate ΔQd calculated from the current clutch residual oil amount Qc is subtracted (Qc−ΔQd), and this is updated and stored as a new current clutch residual oil amount Qc. finish. As can be seen from this, when the clutch command oil pressure Pi is 0.6 (Kgf / cm ² ) or less, the clutch residual oil amount Qc is calculated from the full oil amount (100%) to the empty oil amount (0%). The clutch residual oil amount Qc is estimated by decreasing based on the decrease rate ΔQd.
[0042]
As described above, when the parameter calculation (step S1) in the main flow of FIG. 2 is completed, the shift mode setting in step S2 is performed. The contents of this shift mode setting are shown in FIG. In this flow, first, in step S21, the position range signal PRS from the position sensor 41 is detected, and the position range set by operating the shift lever is detected. In step S22, the current gear stage GA is determined by detecting the currently engaged clutch. In step S23, a known shift map (shift scheduling map, not shown) is searched from the current vehicle speed V and the engine throttle opening TH detected in step S11, and the detected destination on the shift map. The gear stage GBP is obtained.
[0043]
In step S24, it is determined whether or not the detected destination gear stage GBP thus obtained matches the destination gear stage GB set and stored in the previous flow. This is to determine whether or not the vehicle speed V or the throttle opening TH is changed and the destination gear stage is changed after the predetermined shift is started while the predetermined shift is being performed. Is. If it is determined that GB = GBP (YES), the process proceeds to step S27, and the destination gear stage GB (= GBP) set and stored in the previous flow is held as it is. To do. This is control performed when the predetermined shift is started and then the shift is continued as it is, or when the shift is not performed and the vehicle is traveling normally.
[0044]
On the other hand, when it is determined in step S24 that GB ≠ GBP (when NO is determined), the process proceeds to step S25, and is set in a shift permit process (step S8, see FIG. 26) described later. It is determined whether or not the permit flag FP = ON. Although details will be described later, when the permit flag FP = ON (YES), switching to another new shift is permitted during the shift, and the process proceeds to step S26 to detect the detected destination gear stage GBP. Is set and stored as a new destination gear stage GB. On the other hand, when FP = OFF (NO), switching to another new shift is prohibited during the shift, and the process proceeds to step S27, and the destination set and stored in the previous flow. The gear stage GB is held as it is. Thereafter, the process proceeds to step S28, where a shift mode for shifting the current shift stage GA set as described above to the destination shift stage GB is set, and the shift mode setting subflow (step S2) is ended.
[0045]
Next, returning to the main flow, the process proceeds to step S3, where engagement control of the lockup clutch LC of the torque converter TC is performed. Since this engagement control has been well known and is not related to the present invention, the description thereof will be omitted.
[0046]
Thereafter, the process proceeds to step S4, and shift control is performed to perform automatic shift by performing engagement control of the clutches C1 to C5. The contents of this shift control are shown in FIG. In this sub-flow, first, in step S5, input torque to the main shaft MS of the transmission TM is estimated.
[0047]
The input torque estimation content in step S5 is shown in FIG. 10, which will be described first. Here, first, the gross output torque of the engine ENG is calculated. Since the engine output torque is determined according to the intake negative pressure PBA and the engine rotational speed NE, an engine output torque map is set and stored in advance corresponding to the intake negative pressure PBA and the engine rotational speed NE. The engine output torque corresponding to the current engine intake negative pressure PBA and the engine rotational speed NE detected in step S11 can be read from the output torque map. However, since the engine ENG has a variable valve timing mechanism and the engine output torque map varies depending on the operation switching, the output torque calculation (step S51) is performed according to the sub-flow shown in FIG.
[0048]
Here, first, in step S511, it is detected whether the operating characteristic VT of the variable valve timing mechanism is the low speed valve timing characteristic LVT or the high speed valve timing characteristic HVT. This is detected by reading the detection signal VTS from the valve timing switching operation detector 61 read in step S11. Then, in step S512, it is determined whether or not the operation creation VT detected in this way is the low speed valve timing characteristic LVT (VT = LVT). When it is determined that VT = LVT (when it is determined YES), the process proceeds to step S513, and the switching elapsed time from the time when the high speed valve timing characteristic HVT is switched to the low speed valve timing characteristic LVT is t0. It is determined whether it is within seconds.
[0049]
When it is determined that the switching elapsed time exceeds t0 seconds (when it is determined NO), the process proceeds to step S514, and the low-speed valve timing that is measured and set in advance as shown in FIG. The engine gross output torque TEG corresponding to the current engine intake negative pressure PBA and the engine rotational speed NE detected in step S11 is read from the engine output characteristic map at the characteristic LVT.
[0050]
When it is determined in step S513 that the switching elapsed time is within t0 seconds (when it is determined YES), the process proceeds to step S515, and the engine output at the low speed valve timing characteristic LVT shown in FIG. From the characteristic map and the engine output characteristic map at the high speed valve timing characteristic HVT shown in FIG. 12B, the engine gross output torque TEG at the low speed valve timing characteristic LVT corresponding to the current engine intake negative pressure PBA and the engine speed NE. (L) and engine gross output torque TEG (H) at high speed valve timing characteristic HVT are calculated. Then, the engine gross output torque TEG is calculated by continuously changing the engine gross output torque from TEG (H) to TEG (L) during the switching elapsed time t0 seconds.
[0051]
Specifically, this calculation is performed as shown in FIG. Here, the high-speed valve timing characteristic HVT is switched to the low-speed valve timing characteristic LVT at time t1, and the engine gross output torque is changed from TEG (H) to TEG (L from time t1 to time t2 after the switching elapsed time t0 seconds. ) Until the engine gross output torque corresponding to each time is calculated. Thereby, hysteresis is provided for switching between the high speed valve timing characteristic HVT and the low speed valve timing characteristic LVT, and even when the engine output torque changes suddenly at the time of switching, the engine output torque that changes smoothly is calculated. Shift control can be performed smoothly.
[0052]
On the other hand, when it is determined in step S512 that the operating characteristic VT of the variable valve timing mechanism is the high speed valve timing characteristic HVT (VT = HVT) (when it is determined NO), the process proceeds to step S516, where It is determined whether the switching elapsed time from the time when the timing characteristic LVT is switched to the high speed valve timing characteristic HVT is within t0 seconds.
[0053]
When it is determined that the switching elapsed time exceeds t0 seconds (when NO is determined), the process proceeds to step S517, and the engine output characteristic map at the high-speed valve timing characteristic HVT shown in FIG. From this, the engine gross output torque TEG corresponding to the current engine intake negative pressure PBA and the engine rotational speed NE detected in step S11 is read.
[0054]
When it is determined in step S516 that the switching elapsed time is within t0 seconds (when it is determined YES), the process proceeds to step S518, and the engine output at the low speed valve timing characteristic LVT shown in FIG. From the characteristic map and the engine output characteristic map at the high speed valve timing characteristic HVT shown in FIG. 12B, the engine gross output torque TEG at the low speed valve timing characteristic LVT corresponding to the current engine intake negative pressure PBA and the engine speed NE. (L) and engine gross output torque TEG (H) at high speed valve timing characteristic HVT are calculated. Then, the engine gross output torque TEG is calculated by continuously changing the engine gross output torque from TEG (L) to TEG (H) during the switching elapsed time t0 seconds. This calculation is the same as the calculation in step S515. Thereby, hysteresis is provided for switching between the high speed valve timing characteristic HVT and the low speed valve timing characteristic LVT, and even when the engine output torque changes suddenly at the time of switching, the engine output torque that changes smoothly is calculated. Shift control can be performed smoothly.
[0055]
When the engine gross output torque TEG in step S51 is calculated as described above, the process proceeds to step S52, and EGR correction is performed. This is to correct the engine output when the exhaust gas is recirculated by the operation of the exhaust gas recirculator (EGR device), so that the engine output decreases. FIG. 14 shows the contents of this EGR correction control. First, in step S521, the EGR amount (%) detected by the EGR operation detector 62 is read, and in step S522, the torque down coefficient α with respect to the EGR amount is obtained. When exhaust gas recirculation is performed, the engine output torque decreases in accordance with the recirculation exhaust amount, and the relationship is shown in FIG. In FIG. 15, the EGR amount shown on the horizontal axis is 100% when the exhaust gas recirculation amount is 0, and is 90% when the recirculation amount is 10%, and the torque down coefficient shown on the horizontal axis. α is a coefficient indicating the rate at which the engine output torque decreases with respect to the EGR amount.
[0056]
In step S522, the torque down coefficient α corresponding to the current EGR amount (%) detected by the EGR operation detector 62 is read from the map of FIG. In step S523, the engine corrected output torque TEC is calculated by multiplying the engine gross output torque TEG calculated in step S51 by the torque down coefficient α.
[0057]
When the engine correction output torque TEC is calculated in this way, the process returns to the sub-flow of FIG. 10, and auxiliary machine drive correction is performed in step S53. Here, the drive torque TAUX necessary for driving auxiliary machines driven by the engine, such as an alternator and an air conditioner compressor, is subtracted from the engine correction output torque TEC, and the engine net output torque TEN is obtained. calculate. Here, various corrections such as correction based on the engine coolant temperature, correction based on ignition timing adjustment, and the like are performed.
[0058]
As described above, when the auxiliary machine drive correction in step S53 is performed and the engine net output torque TEN is calculated, the process proceeds to step S54, and TC torque ratio correction is performed. This performs torque amplification correction based on the torque ratio in the torque converter TC, whereby the input torque TIN output from the torque converter TC and transmitted to the main shaft MS is calculated.
[0059]
In this way, when the transmission input torque TIN is estimated in step S5 of FIG. 9, the process proceeds to step S41, and it is determined whether or not the gear is currently being shifted. When it is determined that the current shift is being performed (when it is determined YES), the process proceeds to step S42, and a shift mode (upshift or downshift) at this shift is determined. When the shift mode is upshift, the process proceeds to step S6 and upshift control is performed. When the shift mode is downshifted, the process proceeds to step S7 and downshift control is performed. When not currently shifting, the process proceeds from step S41 to step S8.
[0060]
First, the upshift control in step S6 will be described with reference to FIG. In the upshift control, in step S61, the engagement instruction hydraulic pressure PiGB for the clutch for setting the destination gear stage GB is set, and in step S62, the release instruction hydraulic pressure PiGA for the clutch for which the current speed stage GA is set is set. The engagement instruction hydraulic pressure PiGB and the release instruction hydraulic pressure PiGA set as described above are output to the linear solenoid valve of the hydraulic control valve HCV (step S63), the operation is controlled, and this is necessary for performing the upshift control. Engage and release the clutch.
[0061]
The setting control content of the engagement instruction hydraulic pressure PiGB in step S61 at this time will be described with reference to FIGS. FIG. 19 shows the passage of time of the shift command signal SH, the engagement instruction hydraulic pressure PiGB, the release instruction hydraulic pressure PiGA, and the shift monitor value SFTMON. Here, the time is increased from the second speed to the third speed at time t0. The case where the shift gear shift command is output is illustrated.
[0062]
In this control, first, in step S611, a basic engagement instruction hydraulic pressure PiGB (Base) is set. This basic engagement instruction oil pressure PiGB (Base) is based on the oil pressure change, input / output rotation speed ratio change, setting timer, etc. in the third speed clutch C3 to be engaged and the second speed clutch C2 to be released. In the time course graph of PiGB in FIG. 19, it is set as indicated by a solid line (PiGB (1) to PiGB (5)). This basic engagement instruction oil pressure PiGB (Base) is set in the preparation mode (shift monitor value SFTMON = 10h) and time t1 to t2 for filling the piston invalid stroke of the third-speed clutch C3 from the shift start time to to t1. Torque phase mode (SFTMON = 20h), inertia phase mode (SFTMON = 30h) set at time t2 to t3, and engagement completion mode (SFTMON = 40h) set after time t3.
[0063]
Note that the time (time from to to t1) for setting the preparation mode (shift monitor value SFTMON = 10h) for reducing the piston invalid stroke is the remaining oil amount Qc (this remaining amount) of the third speed clutch C3 to be engaged. The oil amount Qc is variably set according to the calculation in step S12), and in the subsequent torque phase mode (SFTMON = 20h), inertia phase mode (SFTMON = 30h), and engagement completion mode (SFTMON = 40h). This control is not affected by the residual oil amount Qc. Further, the engagement command hydraulic pressures PiGB (2) and PiGB (3) in the torque phase mode (SFTMON = 20h) are set based on the input torque TIN estimated in step S5.
[0064]
Since the setting of the basic engagement instruction hydraulic pressure PiGB (Base) is conventionally known (for example, see Japanese Patent Application Laid-Open No. 2001-165303 related to the application of the present applicant), the description of the setting is omitted. .
[0065]
When the basic engagement instruction oil pressure PiGB (Base) indicated by the solid line in the graph of the engagement instruction oil pressure PiGB in FIG. 19 is set in this way, the process proceeds to step S612, and the third speed clutch C3 engaged by this instruction oil pressure. It is determined whether this is the first engagement after engine start (ignition IG is turned on). If it is determined that this is the first engagement after the IG is turned ON (YES is determined), the process proceeds to step S613, and the neglect flag FH is set to ON. When the ignition IG is turned off and the engine is stopped, the hydraulic pump drive that supplies the hydraulic oil to the hydraulic control valve HCV is also stopped, and the oil in the control hydraulic supply oil passage and the clutch flows out to the drain. For this reason, when the clutch is first engaged after the ignition is turned on, the clutch engagement is started after the oil thus drained is compensated for, and there is a possibility that a clutch engagement delay occurs. In this flow, the engagement hydraulic pressure is increased (this is referred to as neglect correction) to prevent such a clutch engagement delay. In step S613, the neglect flag FH indicating that this neglect correction is being performed. Turn it on.
[0066]
In step S614, the hydraulic oil temperature (transmission oil temperature) TTM supplied to the clutch is read. In step S615, the neglect correction hydraulic pressure ΔPiHB corresponding to the hydraulic oil temperature TTM is calculated. This neglected correction hydraulic pressure ΔPiHB is set in advance corresponding to the oil temperature (so as to increase when the oil temperature is low), and is calculated by reading the neglected correction hydraulic pressure ΔPiHB corresponding to the hydraulic oil temperature TTM. The neglected correction oil pressure ΔPiHB calculated in this way is, for example, the oil pressure that is hatched in the graph of the engagement instruction oil pressure PiGB shown in FIG. 19, and this is the initial instruction oil pressure (preparation) of the basic engagement instruction oil pressure PiGB (Base). Pressure increase correction is added to the command oil pressures PiGB (1) and PiGB (2)) set in the command and torque phase command oil pressure modes, and the instructions indicated by broken lines PiGB (1) 'and PiGB (2)' in the figure The hydraulic pressure is set (step S616).
[0067]
On the other hand, if it is determined that it is not the first engagement after the IG is turned ON in step S612, that is, if it has already been engaged at least once (if it is determined NO), step S612 is performed. Proceeding to S617, the neglect flag FH is set to OFF, and this subflow is terminated while the basic engagement instruction hydraulic pressure PiGB (Base) is set.
[0068]
By performing the setting control of the engagement instruction oil pressure PiGB as described above, when the clutch is first engaged after the IG is turned on and the engine is started, the neglect correction oil pressure corresponding to the hydraulic oil temperature TTM is used. By ΔPiHB, the initial instruction oil pressure of the basic engagement instruction oil pressure PiGB (Base) (instruction oil pressures PiGB (1) and PiGB (2) set in the preparatory and torque phase instruction oil pressure modes) is increased. As a result, hydraulic oil is rapidly supplied to the engagement clutch (third speed clutch C3), and it is possible to suppress delay of the initial clutch engagement.
[0069]
Next, the setting control content of the release instruction hydraulic pressure PiGA for the second speed clutch C2 in which the current gear stage GA is set in step S62 will be described with reference to FIGS. First, in step S621, a basic release instruction hydraulic pressure PiGA (Base) is set. This basic release instruction oil pressure PiGA (Base) is determined based on the oil pressure change, input / output rotation speed ratio change, setting timer, and the like in the third speed clutch C3 to be engaged and the second speed clutch C2 to be released. 19 is set as indicated by a solid line (PiGA (1) to PiGA (3)) in the PiGA time course graph. The basic release command hydraulic pressure PiGA (Base) is set to the standby command hydraulic pressure PiGA (1) set to wait until the piston invalid stroke filling of the third speed clutch C3 is completed and the engagement is started, and the release command hydraulic pressure PiGA (Base). It consists of a lowering instruction oil pressure PiGA (2) to be reduced to PiGA (3) and a release instruction oil pressure PiGA (3) set in the engaging stage of the third speed clutch C3. Note that the standby instruction hydraulic pressure PiGA (1) needs to be set so as to be a hydraulic pressure that can be transmitted while holding the input torque, and this setting is performed based on the input torque TIN estimated in step S5. Since the setting of such basic release instruction hydraulic pressure PiGA (Base) is also conventionally known, the description of the setting is omitted.
[0070]
When the basic release instruction hydraulic pressure PiGA (Base) indicated by the solid line in the graph of the release instruction hydraulic pressure PiGA in FIG. 19 is set in this way, the process proceeds to step S622, and it is determined whether or not the neglect flag FH is ON. . If it is determined that FH = ON (YES is determined), the process proceeds to step S623 and step S624, and the neglect correction is performed in accordance with the clutch hydraulic oil temperature (transmission oil temperature) TTM read in step S614. The hydraulic pressure ΔPiHA and the cut start delay time t (DEL) are calculated. Then, the standby instruction oil pressure PiGA (1) and the decrease instruction oil pressure PiGA (2) of the basic release instruction oil pressure PiGA (Base) are hatched in FIG. 19 using the neglected correction oil pressure ΔPiHA and the cut start delay time t (DEL). The correction standby instruction hydraulic pressure PiGA (1) ′ and the correction decrease instruction hydraulic pressure PiGA (2) ′ are calculated (step S625).
[0071]
This increase correction will be described in detail. The neglected correction hydraulic pressure ΔPiHA and the disconnection start delay time t (DEL) are set to be larger values as the clutch hydraulic oil temperature TTM becomes lower. For example, in this example, when the clutch hydraulic oil temperature TTM is −20 ° C. or lower, ΔPiHA = 1.0 kgf / cm ² (= 98000 Pa), t (DEL) = 0.1 seconds are set, and the clutch hydraulic oil When the temperature TTM exceeds −20 ° C. and becomes −10 ° C. or less, ΔPiHA = 0.3 kgf / cm ² (= 29400 Pa) and t (DEL) = 0.05 seconds are set. When the clutch hydraulic oil temperature TTM exceeds −10 ° C., the neglect correction hydraulic pressure ΔPiHA and the cut start delay time t (DEL) are not set (set to zero).
[0072]
First, the neglected correction hydraulic pressure ΔPiHA is added to the standby instruction hydraulic pressure PiGA (1) of the basic release instruction hydraulic pressure PiGA (Base) to set the corrected standby instruction hydraulic pressure PiGA (1) ′. Further, the correction standby instruction oil pressure PiGA (1) ′ starts to decrease after the cut start delay time t (DEL) from the basic standby instruction oil pressure PiGA (1). At this time, the correction decrease instruction oil pressure PiGA (2) As shown in the figure, ′ is set to have a characteristic of gradually lowering than the basic lowering instruction hydraulic pressure PiGA (2).
[0073]
On the other hand, when it is determined in step S622 that the leaving flag FH is not ON (when it is determined NO), the above-described pressure increase correction is not performed, and the basic release instruction oil pressure PiGA (Base) is set. This subflow is terminated.
[0074]
When the release instruction hydraulic pressure PiGA is set as described above, after the IG is turned on and the engine is started, the clutch is engaged when the upshift control is first performed to engage the clutch. Even in the case of a delay, the standby instruction hydraulic pressure PiGA (1) and the decrease instruction hydraulic pressure PiGA (2) released for the upshift control are increased as described above. It is prevented from blowing up.
[0075]
Next, the downshift control (step S7) will be described with reference to FIG. In this control, the downshift (normal downshift) that is performed while the accelerator pedal is depressed and the downshift (stop) that is performed when the vehicle is stopped by releasing the accelerator pedal and depressing the brake from the running state. Different control is performed in (downshift). Therefore, first, in step S71, it is determined whether or not the current downshift command is a command for performing a stop downshift. When it is determined that the normal downshift is performed instead of the stop downshift (when NO is determined), the process proceeds to step S72 and step S73, and the destination shift stage GB for the normal downshift control is set. The engagement instruction oil pressure PiGB for the clutch to be set is set, and the release instruction oil pressure PiGA for the clutch currently setting the gear stage GA is set. On the other hand, when it is determined that the stop downshift is performed (when it is determined YES), the process proceeds to step S74 and step S75, and the engagement with respect to the clutch for setting the destination shift stage GB for the stop downshift control is performed. The combination instruction oil pressure PiGB is set, and the release instruction oil pressure PiGA for the clutch that is currently set at the gear position GA is set.
[0076]
In step S76, the engagement instruction hydraulic pressure PiGB and the release instruction hydraulic pressure PiGA set in this way are output to the linear solenoid valve of the hydraulic control valve HCV to control the operation thereof, and to perform this downshift control. Performs required clutch engagement and disengagement control.
[0077]
At this time, the engagement instruction oil pressure PiGB and the release instruction oil pressure PiGA for the normal downshift in step S72 and step S73 are set as shown in FIG. FIG. 22 shows the passage of time of the shift command signal SH, the engagement instruction oil pressure PiGB, the release instruction oil pressure PiGA, and the input / output rotation speed ratio (or gear ratio) R in this normal downshift control. A case where a downshift command from the fourth speed to the third speed is output at time t0 is illustrated. The input / output rotational speed ratio R shown in this figure is the ratio between the countershaft rotation NC and the main countershaft rotation NM, and is a value corresponding to the transmission gear ratio. This input / output rotational speed ratio R is used as an index indicating the shift progress degree. As shown in the figure, the current shift speed input / output rotational speed ratio R (GA) is changed according to the progress of the shift. It has changed to (GB). The input / output rotation speed ratio R is expressed as a dimensionless number corresponding to the gear position. For example, when downshifting from the 4th speed to the 3rd speed as in this example, the input / output rotational speed ratio R (GA) = 4.0 at the 4th speed and the input at the 3rd speed. The output rotation speed ratio R (GB) = 3.0, and the degree of progress is represented by a number that gradually decreases from R = 4.0 to R = 3.0 as the shift proceeds. For example, when R = 3.5, the degree of progress is 50%.
[0078]
The engagement instruction oil pressure PiGB set in step S72 is based on the oil pressure change, the input / output rotation speed ratio change, the setting timer, and the like in the 3-speed clutch C3 to be engaged and the 4-R clutch C4 to be released. Thus, it is set as indicated by a solid line (PiGB (1) to PiGB (3)) in the PiGB time lapse graph in FIG. This engagement instruction oil pressure PiGB is set at a preparation mode for filling the piston invalid stroke of the third speed clutch C3 from the shift start time to to t1, a standby mode set at times t1 to t2, and at times t2 to t3. Engaging mode. In normal downshift control, it is only necessary to release the clutch that currently sets the gear position, wait for the engine speed to increase, and then engage the destination gear stage clutch. Has been.
[0079]
The time for setting the preparation mode for reducing the piston invalid stroke (time from to to t1) is the residual oil amount Qc of the third speed clutch C3 to be engaged (this residual oil amount Qc is calculated in step S12). And the subsequent control in the standby mode and the engagement mode is not affected by the residual oil amount Qc. Further, the engagement instruction hydraulic pressures PiGB (2) and PiGB (3) in the standby mode and the engagement mode are set based on the input torque TIN estimated in step S5.
[0080]
Since the setting of the engagement instruction oil pressure PiGB is conventionally known (for example, see Japanese Patent Application Laid-Open No. 2002-130454 related to the application of the present applicant), the description of the setting is omitted.
[0081]
Next, the setting control content of the release instruction hydraulic pressure PiGA for the 4-R clutch C4 performed in step S73 will be described with reference to FIG. 21 and FIG. First, in step S731, the basic release instruction hydraulic pressure PiGA shown in FIG. 22 is set. This basic release instruction oil pressure PiGA is indicated by a solid line in the figure based on the oil pressure change, input / output rotation speed ratio change, setting timer, and the like in the third-speed clutch C3 to be engaged and the 4-R clutch C4 to be released. It is set as indicated by (PiGA (1) to PiGA (5)). The basic release instruction hydraulic pressure PiGA is set based on the input torque TIN estimated in step S5. Since the setting of the command hydraulic pressures PiGA (2) to PiGA (5) excluding the corrected initial pressure PiGA (1) in the release command hydraulic pressure PiGA is conventionally known, the description thereof is omitted, and the corrected initial pressure PiGA ( The setting of 1) will be described.
[0082]
In order to set the corrected initial pressure PiGA (1), the clutch hydraulic oil temperature TTM and the engine throttle opening TH (accelerator opening) are read in step S732, and the change rate ΔTH of the engine throttle opening TH is calculated in step S733. calculate. Then, in step S734, it is determined whether or not TTM ≧ 40 ° C. (This temperature is an example, and is a temperature appropriately set according to the target transmission, clutch, etc.), and TTM <40 °. If C (NO), the process proceeds to step S739, where the corrected initial pressure PiGA (1) = 0 is set. That is, the base release instruction oil pressure PiGA (2) is set from the beginning without setting the corrected initial pressure PiGA (1).
[0083]
When it is determined in step S734 that TTM ≧ 40 ° C. (YES), the process proceeds to step S735, and it is determined whether throttle opening TH ≧ β (predetermined opening). For example, in the present embodiment, the predetermined opening β is set to an opening that is 5/8 of the fully opened opening (WOT). Here, when it is determined that TH <β (NO), that is, when it is determined that the engine throttle opening TH (or the accelerator opening) is equal to or smaller than the predetermined opening, the process proceeds to step S739. The corrected initial pressure PiGA (1) = 0 is set so as to be the base release instruction hydraulic pressure PiGA (2) from the beginning.
[0084]
If it is determined in step S735 that TH ≧ β (YES), the process proceeds to step S736, and it is determined whether or not throttle opening change rate ΔTH ≦ γ (predetermined change rate). For example, in this embodiment, the predetermined change rate γ is set to a change rate at which the change in the throttle opening during 100 milliseconds is + 0.4 / 8. Here, when it is determined that ΔTH> γ (NO), that is, when it is determined that the accelerator pedal is suddenly depressed so that the throttle opening change rate ΔTH exceeds the predetermined change rate, Proceeding to step S739, the corrected initial pressure PiGA (1) = 0 is set, so that the base release instruction hydraulic pressure PiGA (2) is set from the beginning.
[0085]
On the other hand, when it is determined that ΔTH ≦ γ (YES), the routine proceeds to step S737, where the corrected initial pressure PiGA (1) is calculated. This corrected initial pressure PiGA (1) is the indicated hydraulic pressure as hatched in FIG. 22, and for example, its magnitude ΔPiA = 1.0 kgf / cm ² (= 98000 Pa) and ΔtA = 100 msec are set. . In step S738, the corrected initial pressure PiGA (1) is added, and the release instruction hydraulic pressure PiGA indicated by the solid line in FIG. 22 is set. Accordingly, in this case, as shown by hatching in FIG. 22, first, the correction preparation oil pressure PiGA (s) is first lowered to the correction preparation oil pressure PiGA (s) and gradually reduced to the base release instruction oil pressure PiGA (2). The corrected initial pressure PiGA (1) to be decreased to is set.
[0086]
As can be seen from the above description, the release instruction hydraulic pressure PiGA normally set in the downshift control is such that the clutch operating oil temperature (transmission oil temperature) TTM is equal to or higher than a predetermined temperature (40 ° C.) and the throttle opening TH is predetermined open. When the throttle opening change rate ΔTH is equal to or higher than the degree (5/8 opening) and is equal to or lower than the predetermined change rate (change rate at which the change in the throttle opening during 100 milliseconds is + 0.4 / 8). In FIG. 22, a hatched corrected initial pressure PiGA (1) is provided. In other cases, the corrected initial pressure PiGA (1) is set to zero.
[0087]
If the release instruction hydraulic pressure PiGA is set and controlled in such normal downshift control, the release instruction hydraulic pressure PiGA is immediately released to the base in the case of downshift control (kickdown control) performed by sudden depression of the accelerator pedal. Since the command hydraulic pressure is reduced to PiGA (2), the increase in engine rotation due to depression of the accelerator pedal is not hindered, and engine torque fluctuations are not transmitted to the wheels (vehicle body). In the case of downshift control performed by gradually depressing the accelerator pedal, the release instruction oil pressure PiGA is lowered to the correction preparation oil pressure PiGA (s) and then gradually reduced to the base release instruction oil pressure PiGA (2). Therefore, the engine speed can be prevented from rising and an optimum shift time can be ensured. As a result, optimal downshift control is always performed in accordance with the depression speed of the accelerator pedal. The corrected initial pressure PiGA (1) (that is, ΔPiA and ΔtA) may be set corresponding to the speed change mode and the vehicle speed. As a result, it is possible to perform an appropriate shift in the normal downshift control in all shift modes and at any vehicle speed.
[0088]
Next, stop downshift control will be described. As this stop downshift, downshift control from the third speed to the first speed is performed. In this case, as described above, the engagement instruction oil pressure PiGB (engagement instruction oil pressure of the first speed clutch C1) is set in step S74, and the release instruction oil pressure PiGA (release instruction oil pressure of the third speed clutch C3) is set in step S75. However, since the engagement instruction oil pressure PiGB is the same setting as in the normal downshift control, the description thereof is omitted.
[0089]
FIG. 23 shows a setting subflow of the release instruction hydraulic pressure PiGA in the stop downshift control, and FIG. 24 shows the time change characteristics of the release instruction hydraulic pressure PiGA set at this time. Here, first, in step S751, a basic release instruction hydraulic pressure PiGA (Base) as shown by a solid line in FIG. 24 is set. Since the stop downshift is a downshift that is performed when the accelerator pedal is released and the vehicle stops, the basic release instruction hydraulic pressure PiGA (Base) is, as shown, the initial release instruction hydraulic pressure PiGA (1), The base release command hydraulic pressure PiGA (2) and the complete release command hydraulic pressure PiFA (3) are set.
[0090]
Next, in step S752, the clutch operating oil temperature TTM is read, and in step S753, the engine speed NE is read. In step S754, a stop shift correction hydraulic pressure ΔPiDN is calculated. The stop shift correction hydraulic pressure ΔPiDN is set as shown in FIG. 25 corresponding to the clutch hydraulic oil temperature TTM and the engine rotational speed NE. The clutch hydraulic oil temperature TTM and the engine rotational speed NE read in steps S752 and S753 are set. The stop shift correction hydraulic pressure ΔPiDN corresponding to is read. It should be noted that it is preferable to hold and use the value at the start of the shift control as the engine speed NE at this time. Then, the process proceeds to step S755, and the basic release instruction oil pressure PiGA (Base) set in step S751 is added to the stop shift correction oil pressure ΔPiDN read in this way, and the corrected release instruction oil pressure PiGA ′ (shown by a broken line in FIG. 24) is added. This calculates a corrected initial release instruction oil pressure PiGA (1) ′, a corrected base release instruction oil pressure PiGA (2) ′, and a corrected complete release instruction oil pressure PiFA (3) ′).
[0091]
When stop downshift control (downshift from the third speed to the first speed) is performed using the corrected release instruction hydraulic pressure PiGA ′ calculated in this way, the engagement control of the third speed clutch C3 that sets the current gear position. The correction release instruction oil pressure PiGA ′, which is a hydraulic pressure, is variably set according to the oil temperature and the engine rotation speed, and the pressure increase correction is performed so as to increase as the detected oil temperature decreases and as the detected engine rotation speed increases. For this reason, there is no problem that the engine speed is increased due to delay in engagement of the first speed clutch C1 that sets the destination gear position when the hydraulic oil temperature is low, and the engine is warming up Even if the engine idling rotation is changed from the normal operation to the normal operation, there is no problem that the engine rotation blows up or a shift shock occurs at the time of stop downshift.
[0092]
Next, returning to the flow of FIG. 9, the shift permit process of step S8 is performed. This content is shown in FIG. 26. Here, in step S81, it is determined whether or not the shift from the upshift to the further upshift is permitted. In step S82, the shift from the upshift to the downshift is permitted. In step S83, it is determined whether or not a shift from downshift to further downshift is permitted. In step S84, whether or not a shift from downshift to upshift is permitted. In step S85, a determination is made as to whether or not to permit further downshifting (ie, jump downshifting) during downshifting.
[0093]
The control content of the jump downshift in step S85 will be described with reference to FIG. Here, first, in step S851, the main shaft rotational speed NM, the countershaft rotational speed NC, and the clutch hydraulic oil temperature TTM are read. In step S852, the shift progress degree R is calculated. This speed change degree R is the same as that shown in FIG. 22, and is a value corresponding to the input / output rotational speed ratio.
[0094]
Next, in step S853, it is determined whether or not the clutch hydraulic oil temperature TTM ≧ 20 ° C. When TTM ≧ 20 ° C. (YES), the process proceeds to step S855, and when TTM <20 ° C. (NO ), The process proceeds to step S854. In step S854, it is determined whether or not the shift progress degree R is equal to or higher than the low temperature threshold value RSH (LT). If R ≧ RSH (LT) (YES), the process proceeds to step S856, where R <RSH If (LT) (NO), the process proceeds to step S857. On the other hand, in step S855, it is determined whether or not the shift progress degree R is equal to or higher than the high temperature threshold value RSH (HT). If R ≧ RSH (HT) (YES), the process proceeds to step S856. When R <RSH (HT) (NO), the process proceeds to step S858. In step S856, the permit flag FP is set to ON, and in steps S857 and S858, the permit flag FP is set to OFF.
[0095]
In this embodiment, when the downshift control from the 4th speed to the 3rd speed is performed, the shift progress degree R = 4.0 (4th speed) to R = 3.0 (3rd speed) continuously. In this case, the low temperature threshold value RSH (LT) is set to 3.9, and the high temperature threshold value RSH (HT) is set to 3.3.
[0096]
In the shift mode setting subflow (step S2) described with reference to FIG. 8, it is determined in step S25 whether or not the permit flag FP = ON. However, when FP = ON here, even during a shift. Switching to a new shift is permitted. As can be seen from this, the permit flag FP is used when another new shift command is issued in response to an accelerator pedal operation or the like while a certain shift is being performed (for example, from the fourth speed to the third speed). If a command for downshifting to the second speed is issued during downshift control based on the downshift command, the control may be immediately shifted to control based on the new shift command. It is a flag for determining whether or not.
[0097]
In such a case, for example, if the downshift control from the 4th speed to the 3rd speed has progressed to some extent, the downshift control to the 2nd speed is immediately started. May become longer and this clutch may deteriorate, or the engine speed may rise at the end of downshift control due to delay in engagement of the second speed clutch C2. Therefore, as described above, the permit flag FP is set, and only when FP = ON, the shift control based on the new shift command is permitted. In this case, since the permit flag FP is set according to the shift progress degree R, the shift control to the destination shift stage (for example, the downshift control to the third speed) has progressed to some extent. Does not allow the change to the new destination gear (change to the second speed downshift control), and the shift control to the second gear is performed after the shift to the third gear is completed. As a result, the slip time of the fourth speed clutch C4 becomes longer, and there is no possibility that the clutch will deteriorate, and the engine rotation is prevented from blowing up at the end of the downshift control due to the engagement delay of the second speed clutch C2, thereby causing an uncomfortable speed change. Occurrence can be suppressed.
[0098]
Further, the threshold value of the shift progress rate R for setting the permit flag FP = ON is set according to the clutch hydraulic oil temperature (transmission oil temperature) TTM, and the permit flag FP = ON according to the hydraulic oil temperature. The optimum flag is always set according to the hydraulic oil temperature. That is, the threshold value changing unit is configured by steps S853 to S858. Note that the hydraulic oil temperature that is the determination criterion in step S853 is not limited to 20 ° C., and is set as appropriate, and the threshold values RSH (LT) and RSH (HT) set in steps S854 and S855 are also (RSH (LT))> (RSH (HT)).
[0099]
【The invention's effect】
As described above, according to the automatic transmission control device of the present invention, when the variable valve timing mechanism is switched, the engine output torque before switching is smoothly changed from the engine output torque after switching to the engine output torque after switching. Based on the corrected engine output torque corrected in this way, the engagement control oil pressure supplied and controlled by the oil pressure supply control means is set and the shift is performed, so that the calculation engine calculated with the switching operation of the variable valve timing mechanism The output torque does not change abruptly, and smooth and smooth shift control can be performed.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram generally showing a control device for an automatic transmission according to the present invention.
FIG. 2 is a main flow chart showing the operation of the control device of FIG. 1;
FIG. 3 is a subroutine flow chart showing control contents in step S1 of the flow chart of FIG.
4 is a subroutine flow chart showing control contents in step S12 of the flow chart of FIG.
FIG. 5 is a graph showing an indicated hydraulic pressure pattern applied to the clutch for measuring the oil reduction rate of the clutch.
6 is a graph showing a relationship between a low command hydraulic pressure supply time T1 and an elapsed time T2 required to increase the clutch pressure when the command hydraulic pressure in FIG. 5 is applied to the clutch.
7 is a graph showing a relationship between a clutch residual oil amount Qc and an oil reduction rate ΔQd obtained from the relationship of FIG.
FIG. 8 is a subroutine flow chart showing the control contents in step S2 of the flow chart of FIG.
FIG. 9 is a subroutine flow chart showing the control contents in step S4 of the flow chart of FIG.
FIG. 10 is a subroutine flow chart showing the contents of control in step S5 of the flow chart of FIG.
FIG. 11 is a subroutine flow chart showing control contents in step S51 of the flow chart of FIG.
FIG. 12 is a graph showing an output characteristic map of an engine used in the automatic transmission according to the present invention corresponding to the operation of the variable valve timing mechanism.
FIG. 13 is a graph showing a change in engine output calculation torque when the high-speed valve timing characteristic is switched to the low-speed valve timing characteristic.
14 is a subroutine flow chart showing the control contents in step S52 of the flow chart of FIG.
FIG. 15 is a graph showing a relationship between an EGR amount and a torque down coefficient α.
FIG. 16 is a subroutine flow chart showing the control contents in step S6 of the flow chart of FIG.
FIG. 17 is a subroutine flow chart showing the contents of control in step S61 of the flow chart of FIG.
FIG. 18 is a subroutine flow chart showing the contents of control in step S62 of the flow chart of FIG.
FIG. 19 is a graph showing the passage of time of the shift command signal SH, the engagement instruction oil pressure PiGB, the release instruction oil pressure PiGA, and the shift monitor value SFTMON in the upshift control shown in FIG. 16;
20 is a subroutine flow chart showing the control contents in step S7 of the flow chart of FIG.
FIG. 21 is a subroutine flow chart showing the control contents in step S73 of the flow chart of FIG.
22 is a graph showing the passage of time of shift command signal SH, engagement instruction oil pressure PiGB, release instruction oil pressure PiGA, and shift progress degree R in the normal downshift control shown in FIG.
FIG. 23 is a subroutine flow chart showing the control contents in step S75 of the flow chart of FIG.
FIG. 24 is a graph showing a lapse of time of a release instruction hydraulic pressure PiGA in the stop downshift control shown in FIG.
FIG. 25 is a table showing stop shift correction hydraulic pressure ΔPiDN in stop downshift control.
FIG. 26 is a subroutine flow chart showing the contents of control in step S8 of the flow chart of FIG.
FIG. 27 is a subroutine flow chart showing the control contents in step S85 of the flow chart of FIG.
[Explanation of symbols]
11 to 15 1st to 5th drive gear (power transmission path)
21 to 25 1st to 5th driven gear (power transmission path)
61 Valve timing switching operation detector ENG Engine TM Transmission MS Main shaft (power transmission path)
CS counter shaft (power transmission path)
C1-C5 1st-3rd clutch, 4-R clutch, 5th clutch (friction engagement element)
HCV hydraulic control valve (hydraulic supply control means)
ECU control unit

Claims (1)

A plurality of power transmission paths and a plurality of hydraulically actuated friction engagement elements, and the plurality of power transmissions by selectively engaging the plurality of friction engagement elements using hydraulic pressure in accordance with a traveling state. In the automatic transmission configured to select one of the power transmission paths from the path and set the shift speed, and to change the output rotation of the engine based on the set shift speed and transmit it to the wheels,
Hydraulic pressure supply control means for controlling the supply of engagement control hydraulic pressure to the friction engagement element so as to perform a predetermined shift according to a shift instruction;
Engine torque calculating means for calculating the output torque of the engine;
A variable valve timing mechanism capable of switching the operating characteristics of at least one of the intake and exhaust valves of the engine;
Transmission input torque calculation means for calculating transmission input torque input to the transmission from the engine output torque calculated by the engine torque calculation means,
The engine torque calculating means calculates a pre-switching engine output torque corresponding to an operating characteristic before switching and a post-switching engine output torque corresponding to an operating characteristic after switching when the variable valve timing mechanism is switched. Calculating a corrected engine output torque that is corrected so that the previous engine output torque continuously changes from the start of the switching operation to the post-switching engine output torque during the switching elapsed time ;
The transmission input torque calculating means calculates the transmission input torque inputted to the transmission from said engine corrected output torque calculated by the engine torque calculation means,
When the supply control of the engagement control hydraulic pressure for shifting to the friction engagement element is performed by the hydraulic pressure supply control means in accordance with a shift instruction, the engagement control hydraulic pressure for the shift is calculated by the transmission input torque calculating means. A control device for an automatic transmission, wherein the automatic transmission control device is set based on the transmitted input torque.

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