JP2503420B2 - Integrated control device for automatic transmission and engine - Google Patents

Description

Detailed Description of the Invention

[Industrial applications]

The present invention relates to an integrated control device for an automatic transmission and an engine, and more particularly, to an improved integrated control device for an automatic transmission and an engine that maintains good gear shifting characteristics by changing engine torque during shifting. Regarding

[Prior art]

A gear shift mechanism and a plurality of friction engagement devices are provided, and the engagement of the friction engagement devices is selectively switched by operating a hydraulic control device, and a plurality of gear engagement mechanisms are set according to a preset speed change map. Vehicle automatic transmissions configured to achieve any one of the shift speeds are already widely known. Further, in such an automatic transmission for a vehicle, the engine torque is changed at the time of shifting to obtain a good shifting characteristic, and the automatic transmission and the engine which secure and improve the durability of the friction engagement device are integrated. Various control devices have been proposed (for example, JP-A-55-69738). That is, such integrated control of the automatic transmission and the engine changes the amount of torque transmission from the engine at the time of shifting to control the energy absorption amount in each member of the automatic transmission or in the friction engagement device that brakes these members. Then, the gear shifting is completed in a short time and with a small gear shifting shock, giving the driver a good feeling of gear shifting, and
The durability of the friction engagement device is improved.

[Problems to be Solved by the Invention]

However, the frictional engagement device used in the automatic transmission is unavoidable in that its coefficient of friction changes with time, for example, from the time of new vehicle to the passage of time. When the friction coefficient changes in this way, the gear shift time becomes longer and the gear shift shock is reduced, but the durability of the friction engagement device deteriorates. Therefore, in a normal vehicle, the shift time is set to be short in advance when a new vehicle is used so that the durability thereof does not deteriorate so much even if the shift time becomes long over time. However, if the shift time is set short in this way, the shift shock becomes large, and a good driving sensation cannot be obtained. Therefore, conventionally, the durability of the friction engagement device is improved and the shift shock is reduced. There was a problem that it was difficult to achieve both. By the way, in the integrated control device for the automatic transmission and the engine as described above, the torque change amount corresponding to each throttle opening (engine load) is set in advance as a map value. The fact is that no consideration has been given to preventing the effects of changes over time.

[Object of the invention]

The present invention has been made in view of the above-mentioned conventional problems, in which the time change rate of the rotational speed of the rotating member of the automatic transmission is always kept within a predetermined time change rate band, thereby reducing friction. By preventing changes in the shifting time due to changes in the friction coefficient of the engagement device over time, it is possible to always perform shifting in the optimum shifting time from the time of new vehicle to the passage of time. It is an object of the present invention to provide an integrated control device for an automatic transmission and an engine, which can achieve both improvement in performance and reduction in shift shock.

[Means for solving problems]

The present invention is an integrated control device for an automatic transmission and an engine, which is configured to maintain good gear shifting characteristics by changing an engine torque by a predetermined change amount during gear shifting. As shown, the means for obtaining the time change rate of the rotational speed of the rotary member of the automatic transmission at the time of gear shifting, and the time change rate of the rotational speed of the rotary member at the predetermined gear shift under a predetermined engine load are If it is larger than the upper limit value of the predetermined time change rate band, the engine torque change amount is reduced in real time from the predetermined change amount, and if it is smaller than the predetermined time change rate lower limit value, the engine torque change amount. And a means for increasing the change amount in real time over the scheduled change amount, thereby achieving the above object.

[Action]

Normally, if the shift time of the friction engagement device of the automatic transmission is shortened, the shift shock becomes large, but the durability thereof becomes high. Further, if the gear shifting time is lengthened, the gear shifting shock becomes smaller, but the durability becomes lower. Further, if the shift time becomes too long, the shift cannot be completed in the buffer area of the accumulator provided in the automatic transmission in order to reduce shift shocks that occur at the time of shifting, and the high hydraulic pressure that rises up causes the friction engagement device to rise. Not only the durability of the friction engagement device is deteriorated, but also the gear shift shock is increased. Due to the above reasons, in a normal vehicle, even if a change in shift time occurs due to a change over time, the friction engagement device is set in a new vehicle so that the engagement can be completed within the buffer area of the accumulator. The gear shift time is relatively short, and accordingly, the shift shift at the time of a new car is large. Therefore, in the present invention, when integrally controlling the automatic transmission and the engine, the temporal change rate of the rotational speed of the rotating member of the automatic transmission during execution of the change of the engine torque is calculated to obtain a predetermined engine load. If the time change rate of the rotation speed of the rotating member at the time of a predetermined gear shift is larger than the upper limit value of a predetermined predetermined time change rate band, the change amount of the engine torque is made smaller than the predetermined change amount in real time. However, if it is smaller than the lower limit of the predetermined time change rate band, the change amount of the engine torque is made larger than the predetermined change amount in real time. Therefore, for a predetermined gear shift under a predetermined engine load, it is possible to control the change amount of the engine torque during the gear shift to keep the temporal change rate of the rotational speed of the rotating member during the gear shift constant. Therefore, it is possible to prevent the shift time from changing due to the friction coefficient of the friction engagement device in the automatic transmission changing with time. Therefore, according to the present invention, it is possible to always perform the shift in the optimum shift time, and it is possible to prevent the deterioration of the shift shock at the time of a new vehicle and when the vehicle is extremely aged due to the change with time and the deterioration of the durability. Generally, the durability of the friction engagement device is
If the throttle opening is the same, it is determined by the shift time. Further, this shift time is determined depending on the time change rate during the shift. In the present invention, since the torque change amount is controlled according to the obtained time change rate and the shift time is basically set to the predetermined time, even if the change amount of the engine torque is lower than the normal value. There is no disadvantage in terms of durability. In addition, when controlling the torque change amount by detecting the shift time, it is necessary to wait until the shift is completed. In this method, the torque change amount is corrected in real time during the shift. You can In addition, the present invention automatically handles variations that could not be absorbed in the past, such as variations in shift time due to variations in individual engines and variations in friction coefficient of friction engagement devices, variations in engine torque due to intake air temperature, and the like. Can be absorbed. In a preferred embodiment, the predetermined time change rate band is changed according to the type of shift. With this configuration, the engine torque can be controlled according to the type of shift, and the driver can be given a better sense of shift. Further, preferably, the predetermined time change rate band is changed according to the engine load. If you do this,
It is possible to finely eliminate the change in the gear shift shock which varies depending on the change in the engine load, and to give the driver a better sense of gear shift. Further, preferably, the upper limit and the lower limit of the predetermined time change rate band are set to be the same. As a result, the rate of change over time to be compared can be made uniform, so that the number of storage words can be reduced and the cost of the storage element can be reduced. Further, it is preferable that the time change rate of the rotation speed of the rotary member of the automatic transmission is estimated and obtained from the detected value of the engine rotation speed. As a result, the detection of the change in the rate of change over time is slightly delayed, but it is not necessary to newly provide a sensor for detecting the rotation speed of the rotating member in the automatic transmission, and the existing engine rotation speed sensor is not necessary. Since the rate of change with time can be obtained using the detection signal of, the present invention can be applied with a relatively simple configuration and the cost for implementation can be reduced.

【Example】

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 2 is an overall schematic view of an integrated control device for an automatic transmission and an engine, to which the present invention is applied. The engine 1 and the automatic transmission 2 are well known. In the engine 1, the engine control computer 7 controls the fuel injection amount in the injection valve 19 and the ignition timing in the distributor 20 to obtain an engine output corresponding to the accelerator opening and the engine rotation speed. It is becoming like this. Further, in the automatic transmission 2, the solenoid valves S _{1 to} S ₃ of the hydraulic control device 3 are controlled by the automatic transmission control computer 8, and as a result of the oil passage in the hydraulic control device 3 being changed, each friction coefficient is changed. The engagement state of the coupling device is selectively changed so that a shift speed corresponding to the vehicle speed and the accelerator opening can be obtained. That is, the engine control computer 7 includes an engine rotation speed by the engine rotation sensor 9, an intake air amount by the intake amount sensor 10, an intake air temperature by the intake air temperature sensor 11, a throttle opening by the throttle sensor 12, and a vehicle speed sensor 13. Vehicle speed, engine water temperature by engine water temperature sensor 14, brake by brake switch 15
Each signal of ON is input. The engine control computer 7 determines the combustion injection amount and the ignition timing based on these signals. Further, the engine control rule computer 7 is provided with solenoid valves S _{1 to} S ₃ which are turned on and off by an automatic transmission control computer 8.
The respective solenoid signals are also input in parallel, and the shift timing of the automatic transmission is determined by this. On the other hand, the automatic transmission control computer 8
In addition to the signals from the throttle sensor 12, vehicle speed sensor 13, engine water temperature sensor 14, brake switch 15, etc.,
The position of the shift lever by the shift position sensor 16,
The pattern selection switch 17 is used to input a driving selection pattern such as fuel efficiency-oriented driving or power performance-oriented driving, and a signal such as permission to shift to overdrive by the overdrive switch 18 to obtain a shift speed corresponding to the vehicle speed and accelerator opening. As described above, the solenoid valves S _{1 to} S ₃ are ON / OFF controlled. An engine torque control regulation signal is input from the engine control computer 7 to the automatic transmission control computer 8 so that the automatic transmission can determine that the engine 1 regulates the engine torque control. FIG. 3 is a flow chart for integrally controlling the engine and the automatic transmission. In the control routine of the engine control computer 7, it is judged from the signal changes of the solenoid valves S _{1 to} S _{3 that} a gear shift occurs (step 122), and then the change of the engine speed (for example, if it is an upshift, the engine speed is When it is determined that the actual shift has started (step 124), the engine torque is changed according to the change amount of the engine torque (ignition retardation amount) that is predetermined by the type of shift, the throttle opening, etc. Control is started (step 126). The change amount of the engine torque is appropriately changed according to the time change rate of the engine rotation speed, as described later. As a result, the engine torque is changed according to the time change rate of the rotary member of the automatic transmission. As the gear shifts, the engine speed changes to a speed that is the sum of the output shaft speed of the automatic transmission and the engine speed at the end of the gear shift determined by the gear ratio plus a certain value (including a negative number). At some time, it is judged that the shift has been completed (step 128), and then the engine torque control is completed with a comparatively long time over a predetermined time (step 130), and the normal engine control state is restored. Next, the above control will be described in detail with reference to FIGS. 4 and 5. FIG. 4 is a flow chart of the engine control routine. That is, first, the flag F is reset as initialization (step 232). This flag F indicates execution of engine torque control. Then, the fuel injection amount and the ignition timing are determined in the engine control main routine (step 234). Then, a determination flag F (step 236), if the flag F = 0, i.e., not running of the engine torque control determines the necessity of the torque control by the change of the solenoid valve S ₁ to S ₃ (step 238).
If torque control is not necessary, the process returns to step 234. On the other hand, if it is determined that it is necessary, the engine torque change amount (scheduled change amount) and the engine speed corresponding to the throttle opening and the type of shift are changed. Change rate of ΔNe
A predetermined lower limit change rate Ne ₁ and a predetermined upper limit change rate Ne ₂ are determined (step 240). Then, it is judged from the change of the engine speed that the actual shift is started (step 242), and when the shift is actually started, the flag F is set to 1 (step 244). On the other hand, if the flag F = 1 in the previous step 236,
Flow toward step 246. In step 246, the engine torque control is executed according to the engine torque change amount ΔT determined in step 240. Then, the time change rate ΔNe of the engine speed calculated by the calculation routine shown in FIG. 5 described later is read (step 248), and this time change rate ΔNe is compared with the predetermined lower limit change rate Ne ₁ (step 250). . As a result of the comparison, when ΔNe <Ne _{1, that} is, when the time change rate Ne of the engine speed is smaller than the predetermined lower limit change rate Ne ₁ , the engine torque change amount (scheduled change amount) ΔT is increased in real time. For a given value
The value obtained by adding dT is newly set as the engine torque change amount ΔT (step 254). On the other hand, when the time change rate is ΔNe ≧ Ne ₁ , the time change rate ΔNe is compared with the predetermined upper limit change rate Ne ₂ (step 252). As a result of comparison, the time change rate ΔNe
> Ne ₂ , that is, when the time change rate ΔNe is larger than the predetermined upper limit change rate Ne ₂ , the engine torque change amount (scheduled change amount) ΔT is reduced in real time. The subtracted value is newly set as the engine torque change amount ΔT (step 256). Note that the time change rate ΔN
When e is Ne ₁ ≤ΔNe ≤Ne ₂ , the value of the time change rate ΔNe remains unchanged, and the current flows to step 258. Then, the change amount ΔT of the engine torque determined in steps 252, 254 and 256 is changed to a value corresponding to the throttle opening and the type of shift (step 258), and the end of the shift is determined (step 260). If the gear change is not completed, the process returns to the previous step 234 again, and if it is determined that the gear change is completed, the torque control end routine for returning to the normal engine control state is executed (step 262) and the flag F is reset. Then (step 264), it flows to the previous step 234. FIG. 5 is a flow chart showing a routine for calculating the time change rate ΔNe of the engine rotation speed in the routine shown in FIG. This calculation routine is a routine that is executed when there is an interrupt request after the lapse of a predetermined time T (step 332). When this routine is executed, the previously stored engine rotation speed Nei _-1 is first cleared (step 33
Four). Next, the engine rotation speed Nei stored this time is newly stored as the previous engine rotation speed Nei _-1 (step 336). Then, this engine speed Ne is newly read as the engine speed Nei (step 33
8) Then, the time change rate ΔNe of the engine speed is calculated by the following equation (1) (step 340). ΔNe = (Nei ₋₁ −Nei) / T (1) That is, by dividing the difference between the previous engine speed Nei ₋₁ and the current engine speed Nei by the predetermined time T, the engine speed time The rate of change ΔNe is obtained. According to this embodiment, for a predetermined shift at a predetermined throttle opening, the engine torque is changed during the shift, and the time change rate ΔNe of the engine rotation speed during the shift is always maintained at Ne ₁ ≤ ΔNe ≤ Ne ₂ . It becomes possible to do. Therefore, it is possible to prevent the shift time from changing due to the change in the friction coefficient of the friction engagement device over time, and to always perform the shift at the optimum shift time. It is possible to achieve both reduction of gear shift shock. Further, since the torque change amount ΔT is corrected only when the time change rate ΔNe is out of the range Ne ₁ ≦ ΔNe ≦ Ne ₂ , the torque change amount is changed due to the variation of the time change rate. It is possible to prevent the amount from being unnecessarily hunted and corrected. In the above embodiment, the time rate of change of the rotational speed of the rotary member of the automatic transmission is estimated from the time rate of change of the engine rotational speed for cost reduction. However, the method of obtaining the time change rate in the integrated control device for the automatic transmission and the engine according to the present invention is not limited to the method based on the engine rotation speed as described above, and can be directly detected by the sensor or the like from the rotating member. Clearly what is required. In this case, since the change in the rotation speed of the rotating member is directly detected, the detection delay due to the interposition of the torque converter can be prevented, and the time change rate can be calculated more accurately than in this embodiment.

【The invention's effect】

As described above, according to the present invention, for a predetermined gear shift under a predetermined engine load, the time change rate of the rotational speed of the rotating member of the automatic transmission at the time of the gear change can always be maintained at the predetermined time change rate. As a result, the shift time can be constantly managed. Therefore,
The change in the shift time due to the change over time of the friction coefficient of the friction engagement device can be eliminated, and the shift can always be performed at the optimum shift time from the time of a new vehicle to the passage of time. It is possible to obtain the excellent effect that it is possible to achieve both the improvement of the durability and the reduction of gear shift shock.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the essential constitution of the present invention, and FIG. 2 is an overall block diagram showing the constitution of an embodiment of an integrated control device for an automatic transmission and an engine according to the present invention. 3, FIG. 3 is a flow chart showing an engine torque control routine adopted in the above-mentioned embodiment apparatus, FIG. 4 is a flow chart showing the same engine control routine, and FIG. 5 is a flow chart showing the engine rotation speed in the engine control routine. 6 is a flowchart showing a calculation routine for calculating a time change rate. 1 ... Engine, 2 ... Automatic transmission, 7 ... Engine control computer, 8 ... Automatic transmission control computer, Ne ₁ , Ne ₂ ...
lower limit.

Claims (5)

(57) [Claims] 1. An integrated control device for an automatic transmission and an engine, wherein an engine torque is changed by a predetermined change amount at the time of shifting to maintain good shifting characteristics. A means for obtaining a time change rate of the rotational speed of the rotary member of the transmission; and a time change rate of the rotational speed of the rotary member at a predetermined speed change under a predetermined engine load, which is within a predetermined time change rate band. If it is larger than the upper limit value, the engine torque change amount is reduced in real time from the predetermined change amount, and if it is smaller than the lower limit value of the predetermined time change rate band, the engine torque change amount is changed from the predetermined change amount in real time. An integrated control device for an automatic transmission and an engine, characterized by comprising: 2. The integrated control device for an automatic transmission and an engine according to claim 1, wherein the predetermined time change rate band is changed according to the type of shift. 3. The integrated control device for an automatic transmission and an engine according to claim 1, wherein the predetermined time change rate band is changed according to an engine load. 4. The integrated control device for an automatic transmission and an engine according to any one of claims 1 to 3, wherein the upper limit and the lower limit of the predetermined time change rate band are set to be the same. 5. The automatic system according to claim 1, wherein the time change rate of the rotational speed of the rotary member of the automatic transmission is estimated and obtained from the detected value of the engine rotational speed. Integrated control device for transmission and engine.