JPH07290998A - Control device of engine and automatic transmission - Google Patents

Abstract

PURPOSE:To efficiently restrain a speed changing shock by setting et input torque in accordance with input torque of an automatic transmission and inertia torque following change of rotation of the transmission and simulatneously, lowering the target input torque at the time of changing speed by way of setting target hydraulic pressure. CONSTITUTION:Supposing that shift up speed changing is carried out in the state where torque down is possible, target torque Tm at the time of speed changing is set at a point of time t1 when shift up judgement is carried out, and target line pressure P is set by input torque hydraulic pressure set in accordance with the target torque Tm at the time of speed changing and inertia torque hydraulic pressure Pi found in correspondence with target speed changing time Ts from an inertia torque hydraulic pressure setting map. Thereafter, after output shaft torque passes a temporarily lowering torque phase T, engine torque Te is lowered so that the target torque Tm is realized at a point of time t2 when output torque is transferred to a rising inertia phase 1, and the inertia torque hydraulic pressure Pi is also reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an engine and an automatic transmission in a power plant for a vehicle, and more particularly to a control device for controlling the engaging force of friction elements by hydraulic pressure.

[0002]

2. Description of the Related Art Automatic transmissions installed in automobiles are
A torque converter to which an engine output is input and a speed change mechanism driven by the output of the converter are combined, and a power transmission path of the speed change mechanism is switched by selective operation of a plurality of friction elements such as clutches and brakes.
It is configured to automatically shift to a predetermined gear according to the driver's request and driving condition.In this type of automatic transmission, the hydraulic pressure that generates the line pressure for engaging the friction element is set. A control circuit is provided. In that case, if the line pressure generated by this hydraulic control circuit is too low with respect to the input torque to the friction element, the torque transmission capacity of the friction element will be insufficient, and the required torque cannot be transmitted reliably, For example, at the time of gear shifting, the friction element unnecessarily slips to deteriorate the feeling of gear shifting, and the durability of the friction element is impaired. On the other hand, if the line pressure is too high, for example, an excessive shift shock will occur during shifting, or the torque for driving the oil pump will be unnecessarily large and the engine output will be consumed excessively. It will deteriorate fuel efficiency.

To address this, for example, Japanese Unexamined Patent Publication No. 3-249.
As described in Japanese Patent Publication No. 466, the line pressure is set based on the input torque, while the line pressure is controlled while the input torque is fixed to a value immediately before the shift operation is started during the gear shift, and the throttle is controlled. There is a system in which the line pressure is corrected according to the change rate of. According to this, since the line pressure during shifting is controlled substantially corresponding to the output torque of the engine, it is expected to obtain good shifting characteristics.

[0004]

However, in the prior art described in the above publication, the output torque of the engine is not adjusted at the time of gear shifting, so gear shifting shock cannot be effectively suppressed.

The present invention addresses the above problems in a vehicle power plant in which an engine and an automatic transmission are combined, and an object thereof is to effectively suppress a shift shock.

[0006]

That is, the invention of claim 1 of the present application (hereinafter referred to as the first invention) includes an engine whose output torque can be adjusted, and an automatic transmission to which the output torque of the engine is input. In a vehicle power plant in which the above are combined, a target input torque setting means for setting a target input torque at the time of shifting based on an input torque input to the automatic transmission and an inertia torque caused by a change in rotation of a transmission mechanism, , A target hydraulic pressure setting means for setting a target hydraulic pressure during a shift based on the set target input torque and the inertia torque, and an engine torque for lowering the engine torque so that the input torque becomes the target input torque during a shift A control means, and a hydraulic control means for setting the operating oil pressure during shifting based on the smaller of the actual input torque and the target input torque. Characterized by providing.

The invention of claim 2 of the present application (hereinafter, referred to as the second
The invention) is an engine with adjustable output torque,
In a vehicle power plant in which an automatic transmission to which the output torque of the engine is input is combined, during a shift based on the input torque input to the automatic transmission and an inertia torque caused by a change in rotation of a transmission mechanism. Target input torque setting means for setting the target input torque of the target torque, target hydraulic pressure setting means for setting the target hydraulic pressure at the time of gear shift based on the set target input torque and the inertia torque, and Engine torque control means for reducing the engine torque so as to obtain the input torque, and when the actual input torque during the shift is larger than the target input torque, the working hydraulic pressure during the shift is set to a hydraulic pressure corresponding to the target input torque, When the actual input torque is not larger than the target input torque, the working hydraulic pressure is compared with the actual input torque. Characterized in that a hydraulic control means for setting the hydraulic pressure.

In the invention of claim 3 of the present application (hereinafter referred to as the third invention), the input torque is determined based on a parameter including at least the intake air amount of the engine in the configurations of the first and second inventions. It is characterized in that it is configured as follows.

Further, the invention of claim 4 of the present application (hereinafter referred to as the fourth invention) is the engine torque control means according to the first to third inventions, when the actual input torque is larger than the target input torque in the inertia phase. In addition, the engine torque is fixed to a predetermined value corresponding to the target input torque.

The invention of claim 5 of the present application (hereinafter referred to as the fifth
In addition to the configurations of the above first to fourth inventions,
A target shift time setting means for setting a target shift time based on the amount of change in the input side rotational speed of the speed change mechanism before and after the shift and the input torque is provided, and the shift operation is performed within the target shift time set by the setting means. The feature is that the change rate of the input side rotation speed to be completed is adopted as a substitute value for the inertia torque.

Further, according to the invention of claim 6 of the present application (hereinafter referred to as the sixth invention), in addition to the configuration of the first to fifth inventions, the target shift time is changed according to the actual input torque during the shift. The target shift time changing means and the inertia torque hydraulic pressure changing means for changing the inertia torque corresponding to the inertia torque to a smaller value as the changed target shift time becomes longer are provided.

[0012]

According to the above construction, the following operation can be obtained.

That is, in any of the first to sixth inventions, the target input torque is set based on the input torque input to the automatic transmission and the inertia torque caused by the change in the rotation of the transmission mechanism of the transmission. At the same time, the target hydraulic pressure is set based on the target input torque and the inertia torque. Therefore, by lowering the target input torque at the time of gear shifting, the working hydraulic pressure is reduced to the required hydraulic pressure of the friction element while reducing the torque. Therefore, the shift shock can be effectively suppressed.

In particular, according to the first aspect of the invention, the operating oil pressure during shifting is set based on the smaller value of the actual input torque and the target input torque. Even if the actual input torque becomes lower than the target input torque due to the above, the operating oil pressure is also reduced accordingly, and thereby the torque shock at the end of the shift is suppressed.

According to the second aspect of the invention, when the actual input torque during the shift is larger than the target input torque,
The operating oil pressure during shifting is set to the oil pressure corresponding to the target input torque, and when the actual input torque is not larger than the target input torque, the operating oil pressure is set to the oil pressure corresponding to the actual input torque. Therefore, the same effect as that of the first invention can be obtained.

According to the third aspect of the invention, since the input torque is determined based on the parameter including at least the intake air amount, the working oil pressure can be controlled so as to accurately correspond to the required oil pressure. Therefore, the shift shock can be effectively prevented.

On the other hand, according to the fourth aspect of the invention, when the actual input torque is larger than the target input torque in the inertia phase, the engine torque is fixed to a predetermined value corresponding to the target input torque. Gear shift operation is performed.

According to the fifth aspect of the invention, the target shift time is set based on the input torque and the amount of change in the input side rotational speed of the speed change mechanism before and after the shift, and the shift operation is completed within the target shift time. Since the rate of change of the input side rotational speed to be used is a substitute value for the inertia torque, the target input torque and target hydraulic pressure at the time of shifting can be set easily and accurately in correspondence with the operating state.

Further, according to the sixth aspect of the invention, the target shift time is changed according to the actual input torque during the shift, and the longer the changed target shift time, the smaller the inertia torque corresponding to the inertia torque is changed. Therefore, the torque shock at the end of the gear shift is further reduced.

[0020]

EXAMPLES Examples of the present invention will be described below.

As shown in FIG. 1, an automobile 1 to which the present invention is applied has left and right front wheels 2a and 2b as driving wheels, and an output torque of an engine 3 is changed from an automatic transmission 4 to a differential device 5. And the front wheel 2 via the left and right drive shafts 6a, 6b
It is adapted to be transmitted to a and 2b. The engine 3 is provided with spark plugs 7 ... 7 for each cylinder.

On the other hand, as shown in FIG. 2, the automatic transmission 4 includes a torque converter 20 connected to the output shaft 8 of the engine 3 and a transmission mechanism 30 to which the output torque (turbine torque) is input. , A plurality of friction elements 4 such as clutches and brakes for switching the power transmission path of the mechanism 30
1 to 46 and one-way clutches 51 and 52, and a hydraulic control unit 60 that switches the gear ratio (gear stage) of the transmission mechanism 30 by selectively supplying a line pressure to the friction elements 41 to 46. With these, each range of D, S, L, and R as a traveling range, 1 to 4 speeds in the D range, 1 to 3 speeds in the S range, and 1 to 2 speeds in the L range
You can get speed.

The torque converter 20 is a pump 2 fixed in a case 21 connected to the engine output shaft 8.
2 and the pump 22 disposed so as to face the pump 22.
A turbine 23 driven by hydraulic oil by means of a hydraulic fluid, and a stator 25 provided between the pump 22 and the turbine 23 and supported by the transmission case 9 via a one-way clutch 24 to increase the torque. , Case 2 above
1 and the turbine 23, and is constituted by a lock-up clutch 26 that directly connects the engine output shaft 8 and the turbine 23 via the case 21. The rotation of the turbine 23 is output to the transmission mechanism 30 side via the turbine shaft 27. Here, a pump shaft 10 penetrating the inside of the turbine shaft 27 is connected to the engine output shaft 8 so that the oil pump 11 provided at the end of the transmission 4 opposite to the engine side is driven by the shaft 10. Has become.

On the other hand, the speed change mechanism 30 is composed of a Ravigneaux type planetary gear unit, and the turbine shaft 27
A small diameter small sun gear 31 loosely fitted on the upper side, and a large diameter large sun gear 32 also loosely fitted on the turbine shaft 27 on the opposite engine side of the sun gear 31.
A plurality of short pinion gears 33 meshed with the small sun gear 31, a half portion on the engine side meshed with the short pinion gear 33, and a half pinion gear 34 on the opposite side of the engine meshed with the large sun gear 32. And a carrier 35 that rotatably supports the long pinion gear 34 and the short pinion gear 33.
And the ring gear 3 meshed with the long pinion gear 34.
6 and 6.

A forward clutch 41 and a first one-way clutch 51 are provided in series between the turbine shaft 27 and the small sun gear 31, and a coast clutch 42 is provided in parallel with these clutches 41, 51. A 3-4 clutch 43 is provided between the turbine shaft 27 and the carrier 35, and the turbine shaft 27 and the large sun gear 3 are provided.
A reverse clutch 44 is interposed between the two. A 2-4 brake 45, which is a band brake for fixing the large sun gear 32, is provided between the large sun gear 32 and the reverse clutch 44, and between the carrier 35 and the transmission case 9. , A second one-way clutch 52 that receives the reaction force of the carrier 35
And a low reverse brake 46 that fixes the carrier 35.
And are provided in parallel. Then, the ring gear 3
6 is connected to the output gear 12, and the rotation is transmitted from the output gear 12 to the left and right front wheels 2a and 2b via the differential device 5.

Table 1 below summarizes the relationship between the operating states of the friction elements 41 to 46 such as the above-mentioned clutches and brakes and the one-way clutches 51 and 52 and the shift speeds.

[0027]

[Table 1] Further, a control unit (hereinafter referred to as an ECU) 70 that integrally controls the engine 3 and the automatic transmission 4 is provided. The ECU 70 includes a signal from a vehicle speed sensor 71 that detects a vehicle speed of the automobile 1 and a throttle of the engine 3. A signal from a throttle sensor 72 that detects the opening of a valve, a signal from an air flow sensor 73 that detects the intake air amount of the engine 3, a signal from an engine rotation sensor 74 that detects the engine speed, and a cooling water temperature of the engine 3. A signal from a water temperature sensor 75 that detects the rotation speed, a signal from a turbine rotation sensor 76 that detects the output rotation speed (turbine rotation speed) of the torque converter 20, and a signal from an output rotation sensor 77 that detects the output rotation speed of the speed change mechanism 30. , A shift position sensor for detecting the shift position (range) by the select lever 13 Signal from the 8, and input signals such as from an oil temperature sensor 79 for detecting a hydraulic oil temperature of the automatic transmission 4, for the automatic transmission 4, the hydraulic control unit 60
61 for gear shifting control and a duty solenoid valve 62 also provided for the hydraulic control unit 60 for line pressure control, and for the engine 3 ignition of spark plugs 7 ... It is designed to control. further,
In this embodiment, control is performed to reduce the output torque of the engine 3 by ignition control during gear shifting.

Now, the structure of the line pressure control portion of the hydraulic control unit 60 will be described.

As shown in FIG. 3, the oil pump 11 described above is used.
A regulator valve 63 for adjusting the pressure of the hydraulic oil discharged from the regulator to a predetermined line pressure, and the regulator valve 6
Throttle modulator valve 6 for supplying control pressure to 3
4 and are provided. A constant pressure line 67 is introduced into the throttle modulator valve 64 from a main line 65 through which the hydraulic oil from the oil pump 11 is discharged, and a reducing valve 66 for reducing the hydraulic oil to a constant pressure. And a pressure boosting line 68 is led from the modulator valve 64 to a pressure boosting port 63a provided at one end of the regulator valve 63. A control pressure line 69 branched from the constant pressure line 67 is connected to a control port 64a at one end of the throttle modulator valve 64.

The control pressure line 69 is connected to the duty solenoid valve 6 for line pressure control shown in FIG.
2 is installed and a control pressure corresponding to the duty ratio of the duty solenoid valve 62 is introduced into the control port 64a of the throttle modulator valve 64, so that the pressure is supplied from the line 67 through the control pressure line 69. The pressurized constant pressure is adjusted to the pilot pressure or the pressure according to the duty ratio, and then supplied to the pressure increasing port 63a of the regulator valve 63 via the pressure increasing line 68. . Therefore, the line pressure adjusted by the regulator valve 63 becomes a pressure according to the duty ratio.

Next, the line pressure control and the torque down control at the time of shifting, which are the characteristic parts of the present invention, will be explained. For example, the line pressure control at the time of schedule up shifting is specifically shown in FIGS. 4 and 5. It is performed as follows according to the flowchart.

That is, the ECU 70 reads various signals in step S1 and then determines in step S2 whether or not the shift-up flag Fup is set to 1. When the shift-up flag Fup is set to 1, the rotational change amount ΔNt of the turbine rotational speed Nt before and after the shift is calculated according to the following relational expression (1) in step S3, and in accordance with the relational expression (2) in step S4. The turbine torque Tt is calculated.

ΔNt = Nts−Nos · Go (1) Tt = t · Te (2) Here, Nts is the turbine speed at the time of shift determination, Nos.
Similarly, the output rotation speed of the transmission mechanism 30, Go is the gear ratio after completion of the shift, Te is the engine torque, and t is the torque increase coefficient of the torque converter 20. The engine torque Te is calculated using parameters such as the intake air amount, the engine speed, and the ignition timing, as will be described later.

Next, the ECU 70 proceeds to step S5 to determine whether the engine 3 is in an operating state in which the torque can be reduced. Note that the ECU 70 uses, for example, a water temperature sensor 75
When the cooling water temperature indicated by the signal from indicates the warm-up state of the engine 3, it is determined that the torque can be reduced.

When the ECU 70 determines in step S5 that the torque can be reduced, it executes step S6 and determines whether the lockup clutch 26 of the torque converter 20 is in the OFF state. ECU7
When it is determined that the lock-up clutch 26 is in the OFF state, that is, the torque converter 20 is in the converter state in which the torque is transmitted via the working fluid, the process proceeds to step S7, and the turbine torque Tt and the rotation change amount ΔNt are set in advance. The target shift time Ts is calculated in accordance with the torque-down target shift time map set with the shift pattern (type of shift) Ps as a parameter, and then the target angular acceleration Am is calculated in step S8 according to the following relational expression (3). Calculate

Am = | ΔNt / Ts | (3) That is, the rotation change amount ΔNt before and after the gear shift is calculated as the target gear shift time T.
The value obtained by dividing by s is set as the target angular acceleration Am.

Next, the ECU 70 executes step S9 to determine whether or not immediately after the shift-up flag Fup is switched from 0 indicating the non-shift state to 1 indicating the shift state. That is, it is determined whether or not immediately after the shift determination is performed. The ECU 70 sets the shift-up flag Fup to 0.
When it is determined that it is immediately after switching from 1 to 1,
According to a map in which the turbine torque and the angular acceleration are set as parameters in advance in step S10, the target torque Tm during shifting corresponding to the actual turbine torque Tt and the target angular acceleration Am is set, and step S11 is executed to execute the engine torque. While it is determined whether Te is larger than the target torque Tm during shifting, when it is determined that it is not immediately after the shift-up flag Fup is switched from 0 to 1, step S10 is skipped and the process proceeds to step S11. , It is determined whether the engine torque Te is larger than the gear shift target torque Tm. That is, only during the gear shift determination, the gear shift target torque Tm is set based on the turbine torque Tt and the angular acceleration Ar at that time.

If the ECU 70 determines in step S11 that the engine torque Te is not larger than the gear shift target torque Tm, the ECU 70 proceeds to step S12 and sets the engine torque Te as the gear shift target torque Tm. In S13, the input torque hydraulic pressure Pt corresponding to the gear shift target torque Tm is set, and when it is determined that the engine torque Te is larger than the gear shift target torque Tm, step S12 is skipped and step S13 is executed. The input torque hydraulic pressure Pt corresponding to the target torque Tm during shifting is set. In other words, EC
For example, as shown in FIG. 6, the U70 applies the target torque Tm during shifting to the input torque hydraulic pressure setting map that is set in advance for each shift pattern using the input torque as a parameter to obtain a value corresponding to the target torque Tm. The input torque oil pressure Pt is read out. In this case, the input torque hydraulic pressure setting map is set so that the input torque hydraulic pressure Pt increases as the target torque Tm during shifting (input torque) increases.

Further, the ECU 70 executes step S14, and as shown in FIG. 7, the inertia corresponding to the target angular acceleration Am is based on the inertia torque hydraulic pressure setting map set for each shift pattern using the angular acceleration as a parameter. The torque oil pressure Pi is set. Also in this case, the inertia torque hydraulic pressure setting map is set so that the inertia torque hydraulic pressure Pi increases as the target angular acceleration Am increases.

Then, the ECU 70 executes step S15, and the input torque hydraulic pressure P is calculated according to the following relational expression (4).
target engagement pressure Pcl from t and the inertia torque Pi
Is calculated.

Pcl = Pt + Pi (4) Next, the ECU 70 proceeds to step S16 to calculate the final target line pressure P by correcting the target engagement pressure Pcl with the oil temperature.

That is, generally, the friction element is fastened by frictional contact between the friction members. However, the friction coefficient of the contact surface or the sliding surface of the friction members which are in contact with each other is determined by the operating oil between the friction members. It depends on the temperature To. Specifically, the friction coefficient μ increases as the hydraulic oil temperature To decreases. Therefore, as shown in FIG. 8, for example, from the table of the oil temperature correction coefficient in which the hydraulic oil temperature is set as a parameter, the oil temperature correction coefficient Kμ corresponding to the current hydraulic oil temperature To is obtained.
Then, the final target line pressure P is obtained by substituting the correction coefficient Kμ and the target engagement pressure Pcl into the following relational expression (5).

P = Pcl · kμ (5) Then, the ECU 70 executes step S17 to output the target line pressure P and the target torque Tm during shifting.

Therefore, in the automatic transmission 4, the duty solenoid valve 62 is duty controlled so that the target line pressure P is obtained.

When the ECU 70 determines in step S6 that the lockup clutch 26 is not in the OFF state, that is, when the torque converter 20 is in the lockup state, it branches to step S18 and the turbine torque Tt is set in advance. After calculating the target shift time Ts in accordance with the lock-up torque-down target shift time map set with the rotation change amount ΔNt and the shift pattern (type of shift) Ps as parameters,
In step S8, the target angular acceleration Am is calculated according to the relational expression (3). In this case, the lock-up torque-down target shift time map is set to be longer than the non-lock-up torque-down target shift time map. Therefore,
Target angular acceleration Am calculated according to the above relational expression (3)
Is relatively small compared to the converter state.

As described above, when the torque can be reduced, the target torque Tm during shifting of the engine 3 is set based on the target angular acceleration Am and the turbine torque Tt, and the input torque corresponding to the input torque of the shifting mechanism 30 is set. Since the hydraulic pressure Pt is set based on the target torque Tm at the time of shifting, the input torque hydraulic pressure Pt accurately corresponds to the actual input torque to the speed change mechanism 30 at the time of shifting.

On the other hand, when the ECU 70 determines in the step S5 that the torque reduction of the engine 3 is not possible, the step S19 of the flowchart of FIG. 5 is performed.
Moving to, it is determined whether the lockup clutch 26 of the torque converter 20 is in the OFF state. The ECU 70
When it is determined that the lockup clutch 26 is in the OFF state, that is, the torque converter 20 is in the converter state, the process proceeds to step S20 and the turbine torque Tt is set in advance.
Then, the target shift time Ts is calculated according to the non-torque down target shift time map set with the rotation change amount ΔNt and the shift pattern Ps as parameters, and then the rotation change amount ΔNt and the target shift time Ts are calculated in step S21. By substituting in the above relational expression (3), the target angular acceleration A
Calculate m. In that case, the non-torque down target shift time map is set to be longer than the non-lockup torque down target shift time map.

Then, the ECU 70 executes step S22 to set the engine torque Te to the gear shift target torque Tm.
Then, the process proceeds to step S13 of the flowchart of FIG. 4 and the following steps are executed. Therefore, in this case, the torque reduction of the engine 3 is not performed.

When the ECU 70 determines in step S19 that the lock-up clutch 26 is not in the OFF state, it branches to step S23 and the turbine torque Tt, the rotation change amount ΔNt, and the shift pattern (type of gear change) Ps are stored in advance. After calculating the target shift time Ts according to the lock-up non-torque down time target shift time map set as a parameter, step S2
At 1, the target angular acceleration Am is calculated according to the above relational expression (3). In this case, the lock-up non-torque down target shift time map is set to be longer than the non-lock-up non-torque down target shift time map. Therefore, the target angular acceleration Am calculated according to the above relational expression (3) has a relatively smaller value than in the converter state.

Next, the torque down control during the upshift will be described with reference to the flowchart of FIG.

That is, the ECU 70 reads various signals in step T1, determines whether or not the upshift flag Fup is set to 1 in step T2, and if the flag Fup is set to 1 In step T3, it is determined whether the torque down flag Ftd is set to 1. Here, the torque down flag Ftd is set to 1 when the torque down is executed, and is reset to 0 when the torque down is completed.

When the ECU 70 determines in step T3 that the torque down flag Ftd is not set to 1, the ECU 70 proceeds to step T4 and determines the actual gear ratio Gr calculated from the turbine speed Nt and the output speed No.
Is smaller than a predetermined torque down start determination value g ₁ (Nt), and when YES is determined, step T5 is executed to set the torque down flag Ftd to 1 and then to step T6. move on. Here, the torque down start determination value g ₁ (Nt) is set to a value slightly smaller than the gear ratio before shifting. Therefore, for example, the torque down flag Ftd is set to 1 when the turbine speed Nt is slightly lower than the speed before gear shift, that is, when the turbine speed Nt starts to decrease.

On the other hand, when the ECU 70 determines in step T3 that the torque down flag Ftd is set to 1, the process proceeds to step T7 and the gear ratio is smaller than the predetermined torque down end determination value g ₂ (Nt). If it is determined YES, step T8
Is executed to reset the torque down flag Ftd to 0, and then the process proceeds to step T6. Here, the torque down end determination value g ₂ (Nt) is set to a value that is slightly larger than the gear ratio after shifting. Therefore, for example, when the turbine rotation speed Nt approaches the rotation speed after the gear shift, that is, immediately before the gear shift operation ends, the torque down flag Ftd is reset to 0.

When the ECU 70 proceeds to step T6,
Whether or not the current value Ftd _{(J) of the} torque down flag Ftd is 1 is determined, and when it is determined that the current value Ftd _(J) is 1, the process proceeds to step T9 and the previous value of the flag Ftd is determined. It is determined whether Ftd _(J-1) is 0 or not.
That is, it is determined whether or not it is immediately after the torque down flag Ftd is switched from 0 to 1. And EC
U70 is the previous value Ftd of the torque down flag Ftd.
_When it is determined that _(J-1) is 0, that is, immediately after the torque down flag Ftd is set to 1, the process proceeds to step T10 and the engine torque Te
Is larger than the target torque Tm, and when it is judged that the engine torque Te is larger than the target torque Tm, step T11 is executed, and the target engine torque Mte is calculated according to the following relational expression (6). Then, in step T12, the target engine torque Mte is output.

Mte = Te− (Te−Tm) · K1 (6) Note that K1 (<1) is a predetermined constant.

When the ECU 70 determines in step T9 that the previous value Ftd _(J-1) of the torque down flag Ftd is not 0, the process proceeds to step T13 and whether the engine torque Te is larger than the target torque Tm or not. When it is determined that the engine torque Te is larger than the target torque Tm, step T14 is executed to calculate the target engine torque Mte according to the following relational expression (7).

Mte = max [Tm, (Mte _(J-1) -K2)] (7) In this relational expression (7), max [α, β] are α and β.
It indicates that the larger value of the two is adopted. Also, Mte _(j-1) is the previous target engine torque M
te, and K2 is a constant indicating the reduction rate of Mte.

On the other hand, when the ECU 70 determines in step T6 that the current value Ftd _(J) of the torque down flag Ftd is not 1, the process proceeds to step T16 and the previous value Ftd _{(J-1) of the} flag Ftd is changed. It is determined whether or not 1. That is, it is determined whether or not it is immediately after the torque down flag Ftd is switched from 1 to 0. The ECU 70 then determines the previous value F of the torque down flag Ftd.
When it is determined that td _(J-1) is 1, that is, immediately after the torque down flag Ftd is reset to 0, the process proceeds to step T16, where the engine torque Te is larger than the target torque Tm. Determine whether or not
When it is determined that the engine torque Te is larger than the target torque Tm, step T17 is executed to calculate the target engine torque Mte according to the following relational expression (8).

Mte = (Te−Tm) · K3 + Tm (8) Note that K3 (<1) is a predetermined constant.

When the ECU 70 determines in step T9 that the previous value Ftd _(J-1) of the torque down flag Ftd is not 1, the process proceeds to step T18 and whether the engine torque Te is larger than the target torque Tm or not. When it is determined that the engine torque Te is larger than the target torque Tm, step T19 is executed,
The target engine torque Mte is calculated according to the following relational expression (9).

Mte = min [Te, (Mte _(J-1) + K4)] (9) In this relational expression (9), min [α, β] is the smaller value of α and β. It indicates that it will be adopted. K4 is a constant indicating the rate of increase of Mte.

When the ECU 70 determines in step T2 that the shift-up flag Fup is not 1, the ECU 70 proceeds to step T20 and sets the engine torque Te as the target engine torque Mte.
In step T12, the target engine torque Mte is output.

Further, in this embodiment, even when it is determined in the steps T10, T13, T16 and T18 that the engine torque Te is not larger than the target torque Tm, the step T20 is executed and the target engine is executed. The engine torque Te is set as the torque Mte. Therefore, when the engine torque Te is smaller than the target torque Tm, the engine torque is not controlled.

Here, the engine torque control performed by the ECU 70 will be described. In this embodiment, the engine torque control is performed as follows according to the flowchart of FIG.

That is, the ECU 70 executes steps U1 and U
In step 2, the intake air amount Q and the engine speed Ne are read, and then the air charging efficiency Ce is calculated based on these values. In step U3, the ECU 70 applies the actual engine speed Ne and the air charging efficiency Ce to the map of the basic ignition timing set in advance with the engine speed and the air charging efficiency as parameters, as shown in FIG. , The basic ignition timing Igo corresponding to these is read. In that case, the map of the basic ignition timing is the engine speed Ne.
The higher the value, the larger the advance amount, and the air filling efficiency Ce
Is set so that the larger the value of, the smaller the amount of advance angle.

Then, the ECU 70 reads the engine torque characteristic in step U4, and then calculates the engine torque Te in step U5.

That is, the engine torque T in the normal drive state
As shown in FIG. 12, e can be approximated as a quadratic function for the ignition timing Ig, and if this is expressed by a formula, the following relational expression (10) is obtained.

Te = −a (Ig−b) ² + c (10) where a, b, and c are coefficients that change according to the operating state of the engine 3, and are shown in FIGS. 13 to 15, respectively. As shown, the map is set using the engine speed Ne and the air charging efficiency Ce as parameters. In this case, the function Fa (Ne, Ce) representing the coefficient a has a smaller value of a as the engine speed Ne increases and a value of a as the air charging efficiency Ce increases as shown in FIG. Is set to increase. Further, as shown in FIG. 14, the function Fb (Ne, Ce) representing the coefficient b has a larger value of b as the engine speed Ne increases, and has a smaller value of b as the air charging efficiency Ce increases. Is set to. Then, the function Fc (N
e and Ce) are set to be similar to the output torque characteristic of the engine 3, as shown in FIG.

The ECU 70 calculates the engine torque Te by substituting the coefficients a, b, c read from the above maps and the basic ignition timing Igo at the present time read from the maps into the relational expression (10). As a result, the engine torque when the torque reduction is not performed is obtained. The engine torque Te thus obtained is used as a basis for various calculations.

After calculating the engine torque Te in step U5, the ECU 70 proceeds to step U6 to read the target torque Tm and determines in step U7 whether the engine torque Te is larger than the target torque Tm. When the engine torque Te is larger than the target torque Tm, the target engine torque Mte is read in step U8, and the target ignition timing Mig is calculated according to the relational expression (11) obtained by modifying the relational expression (10).

Mig = b-[(c-Mte) / a]^1/2  (11) Then, the ECU 70 executes step U10 and
Outputs an ignition timing control signal according to the target ignition timing Mig
It

On the other hand, when the ECU 70 determines in step U7 that the engine torque Te is not larger than the target torque Tm, the ECU 70 proceeds to step U11 to set the basic ignition timing Igo as the target ignition timing Mig, and then executes the above step. U10 is executed to output an ignition timing control signal according to the target ignition timing Mig.

Next, the operation of the embodiment will be described.

Assuming that the shift-up shift is performed while the torque can be reduced, as shown in FIG. 16, the shift-up flag Fup is set to 1 at time t1 when the shift-up determination is made. At the same time, as indicated by symbol A, the target torque Tm during shift is set, and the input torque hydraulic pressure set based on the target torque Tm during shift and the target shift time Ts are set from the inertia torque hydraulic pressure setting map. The inertial hydraulic pressure Pi obtained by
Is set. Then, after passing through the torque phase T in which the output shaft torque temporarily decreases as indicated by symbol C, at time t2 when the phase shifts to inertia phase I in which the output torque increases as indicated by symbol D, as indicated by symbol E In addition, the engine torque is reduced so that the target torque Tm is achieved.

By the way, during shifting, for example, the accelerator pedal is released, and the throttle opening θ
May decrease. In this case, since the intake air amount P decreases as the throttle valve closes,
The engine torque Te calculated using the intake air amount Q as a parameter also decreases. In this case, in the operating state in which the engine torque Te becomes lower than the target torque Tm as indicated by the symbol K, the torque down control is canceled and the engine torque Te is also canceled.
The input torque hydraulic pressure Pt is set based on the above. Therefore, as indicated by the symbol K, the input torque hydraulic pressure Pt decreases as the engine torque Te decreases.

In this embodiment, the target shift time Ts is extended as the engine torque Te is reduced, and the inertia torque hydraulic pressure Pi is also reduced in accordance with the extension of the target shift time Ts. . Therefore, after the engine torque Te becomes lower than the target torque Tm, the rate of decrease of the turbine rotation speed Nt is reduced as indicated by the symbol K, and as a result, the shift operation proceeds more slowly than initially. Will be done. This allows
The output shaft torque in the latter half of inertia phase I is
As indicated by the symbol C, the torque gradually decreases, and the torque step ΔT from the time t3 when the inertia phase ends to the torque corresponding to the gear ratio after the gear shift is equal to the torque step ΔT. Therefore, the torque is significantly smaller than the torque change (see reference numeral) when the engine torque Te is controlled to the target torque Tm.

The shift-up flag Fup is reset at time t4 when a predetermined time ta elapses from time t3 when inertia phase I ends.

[0078]

As described above, according to the present invention, the target input torque is set based on the input torque input to the automatic transmission and the inertia torque caused by the change in the rotation of the transmission mechanism of the transmission. At the same time, the target hydraulic pressure is set based on the target input torque and the inertia torque, so by reducing the target input torque during gear shifting, the working hydraulic pressure is reduced to the required hydraulic pressure of the friction element while reducing the torque. Appropriate measures can be taken so that shift shock can be effectively suppressed.

In particular, according to the first aspect of the invention, the hydraulic pressure during shifting is set based on the smaller value of the actual input torque and the target input torque. Even if the actual input torque becomes lower than the target input torque due to the above, the operating oil pressure is also reduced accordingly, and thereby the torque shock at the end of the shift is suppressed.

According to the second aspect of the invention, when the actual input torque during the shift is larger than the target input torque,
The operating oil pressure during shifting is set to the oil pressure corresponding to the target input torque, and when the actual input torque is not larger than the target input torque, the operating oil pressure is set to the oil pressure corresponding to the actual input torque. Therefore, even if the actual input torque is lower than the target input torque, the hydraulic pressure is also reduced accordingly, and in this case also, the torque shock at the end of the shift is suppressed.

According to the third aspect of the invention, the input torque is determined on the basis of the parameter including at least the intake air amount, so that the working oil pressure is accurately controlled in correspondence with the required oil pressure. Therefore, the shift shock can be effectively prevented.

On the other hand, according to the fourth invention, when the actual input torque is larger than the target input torque in the inertia phase, the engine torque is fixed to a predetermined value corresponding to the target input torque. A smooth gear shift operation will be performed.

According to the fifth aspect of the invention, the target shift time is set based on the input torque and the amount of change in the input side rotational speed of the speed change mechanism before and after the shift, and the shift operation is completed within the target shift time. Since the rate of change of the input side rotational speed to be used is a substitute value for the inertia torque, the target input torque and target hydraulic pressure at the time of shifting can be set easily and accurately in correspondence with the operating state.

Further, according to the sixth aspect of the invention, the target shift time is changed according to the actual input torque during the shift, and the inertia torque corresponding to the inertia torque is changed to be smaller as the changed target shift time becomes longer. Therefore, the torque shock at the end of the gear shift is further reduced.

[Brief description of drawings]

FIG. 1 is a control system diagram of an engine and an automatic transmission.

FIG. 2 is a skeleton diagram of an automatic transmission.

FIG. 3 is a circuit diagram showing a line pressure control portion of a hydraulic control unit.

FIG. 4 is a flowchart showing a part of line pressure control during a schedule upshift.

FIG. 5 is a flowchart showing a part of line pressure control.

FIG. 6 is an explanatory diagram of a map used in the control.

FIG. 7 is an explanatory diagram of a map similarly used in the control.

FIG. 8 is an explanatory diagram of a map similarly used in the control.

FIG. 9 is a flowchart showing torque down control performed in parallel with the control.

FIG. 10 is a flow chart showing engine torque control.

FIG. 11 is an explanatory diagram of maps used in the control.

FIG. 12 is a characteristic diagram of engine torque with respect to ignition timing.

FIG. 13 is an explanatory diagram of a map for obtaining a coefficient in an approximate expression of engine torque.

FIG. 14 is an explanatory view of a map for similarly obtaining a coefficient in an approximate expression of engine torque.

FIG. 15 is an explanatory diagram of a map that similarly obtains a coefficient in an approximate expression of engine torque.

FIG. 16 is a time chart diagram showing the operation of the embodiment.

[Explanation of Codes] 3 Engine 4 Automatic Transmission 30 Transmission Mechanism 60 Hydraulic Control Unit 62 Duty Solenoid Valve 63 Regulator Valve 70 ECU 74 Engine Rotation Sensor 76 Turbine Rotation Sensor 77 Output Rotation Sensor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Ueno 3-1, Shinchi Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) Inventor Tetsuya Nishizato 3-3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Corporation Within

Claims (6)

[Claims] 1. A control device for an engine and an automatic transmission in a vehicle power plant in which an engine having adjustable output torque and an automatic transmission to which the output torque of the engine is input are combined. Target input torque setting means for setting a target input torque at the time of gear shift based on the input torque input to the transmission and the inertia torque associated with a change in rotation of the speed change mechanism, the set target input torque and the inertia torque. Target hydraulic pressure setting means for setting a target hydraulic pressure during shifting, engine torque control means for lowering the engine torque so that the input torque becomes the target input torque during shifting, and the operating hydraulic pressure during shifting is actually input A vehicle characterized by being provided with hydraulic control means for setting based on the smaller of the torque and the target input torque. Control device for engine and automatic transmission in dual-purpose power plant. 2. A control device for an engine and an automatic transmission in a power plant for a vehicle, comprising a combination of an engine whose output torque can be adjusted and an automatic transmission to which the output torque of the engine is input. Target input torque setting means for setting a target input torque at the time of gear shift based on the input torque input to the transmission and the inertia torque associated with a change in rotation of the speed change mechanism, the set target input torque and the inertia torque. Target hydraulic pressure setting means for setting a target hydraulic pressure during a shift, engine torque control means for lowering the engine torque so that the input torque becomes the target input torque during a shift, and the actual input torque during the shift is a target. When it is larger than the input torque,
A hydraulic control means for setting the operating hydraulic pressure during shifting to a hydraulic pressure corresponding to the target input torque, and for setting the operating hydraulic pressure to a hydraulic pressure corresponding to the actual input torque when the actual input torque is not greater than the target input torque. A control device for an engine and an automatic transmission in a power plant for a vehicle, wherein: 3. The vehicle power according to claim 1, wherein the input torque is determined on the basis of a parameter including at least an intake air amount of the engine. Control device for engine and automatic transmission in plant. 4. The engine torque control means is configured to fix the engine torque to a predetermined value corresponding to the target input torque when the actual input torque is larger than the target input torque in the inertia phase. A control device for an engine and an automatic transmission in a vehicle power plant according to any one of claims 1 to 3. 5. A target shift time setting means for setting a target shift time on the basis of a change amount of an input side rotational speed of a speed change mechanism before and after a shift and an input torque is provided.
The change rate of the input side rotation speed at which the shift operation is completed within the target shift time set by the setting means is adopted as a substitute value for the inertia torque. A control device for an engine and an automatic transmission in a power plant for a vehicle according to claim 1. 6. A target shift time changing means for changing a target shift time according to an actual input torque during a shift, and an inertia torque for decreasing an inertia torque corresponding to the inertia torque as the changed target shift time becomes longer. 6. A control device for an engine and an automatic transmission in a vehicle power plant according to claim 1, further comprising: a hydraulic pressure changing means.