JPH0613904B2 - Shift control device for automatic transmission - Google Patents

Description

The present invention relates to a shift control device for an automatic transmission, and more particularly to a shift pattern changing technique for an electronically controlled automatic transmission.

(Prior Art) Generally, an automatic transmission has a 1 → 2 shift line or a 2 → 3 shift line based on a vehicle speed and a throttle opening (engine load) according to a predetermined shift pattern as shown in FIG. 12, for example. Upshift to the second speed or the third speed when shifting to the right side region, or downshift to the first speed or the second speed when shifting to the left side region from the 1 ← 2 shift line or the 2 ← 3 shift line. It is configured to automatically shift.

By the way, this variant pattern was assumed to run on a flat road and was determined to optimize the fuel economy and acceleration of the engine, so when traveling on an uphill road, downshifting to a low speed stage is not easily done, It is unavoidable that the insufficient acceleration force continues, and when shifting to downhill running, it is difficult to perform an upshift shift to a high speed stage, resulting in deterioration of fuel efficiency.

Therefore, in order to solve this problem, the present applicant has previously proposed the following shift pattern changing technique for an electronically controlled automatic transmission according to Japanese Patent Laid-Open No. 56-10850.

This shift pattern changing technology determines the reference acceleration of the vehicle from the selected gear position, engine load, and vehicle speed, determines the road gradient from the comparison with the actual acceleration, and shifts according to the comparison result, that is, the road gradient. The shift pattern is changed such that the pattern is selected from several types and used by switching.

(Problems to be Solved by the Invention) However, since this shift pattern changing technique also changes the shift pattern according to the road surface gradient, it has been confirmed that it is difficult to say that it is appropriate. That is, even if the shift pattern matches the road surface gradient, for example, when traveling on an uphill furnace with many curves such as on a mountain road, each time the accelerator pedal is released (the throttle opening is reduced) when approaching the curve, An upshift is made to a higher gear, and a downshift is made to a lower gear each time the accelerator pedal is re-depressed (the throttle opening is increased) while approaching a straight road between curves. As described above, repeated shifts cause a problem of making passengers uncomfortable.

In addition, on an uphill road with a relatively steep road gradient, the vehicle speed is changed to V ₁ by driving from point A through point B to point D to point E in FIG.
When trying to keep this vehicle speed V ₂ after accelerating from V ₂ to
Even if the throttle opening is fully opened to the point F just because the driving force in the third speed is less than the running resistance corresponding to the road surface gradient, it does not pass through the 2 ← 3 shift line, so There was no downshift and the vehicle continued to decelerate, making it impossible to run at constant speed at V ₂ .

This is because it is irreversible and the shift pattern is changed only according to the road surface gradient, and the change state of the engine load is not taken into consideration. Select ON, OF
This is because the change is made by the F switching method.
In any case, the conventional shift pattern changing technique cannot accurately match the change amount of the shift pattern with the driving condition of the vehicle.

It is necessary to change the shift pattern to be different depending on the steering angle of the vehicle. Otherwise, for example, while traveling on an uphill road with many curves, the above-mentioned frequent shift causes a large steering angle with a large steering angle. Despite the sudden turn at the corner, it frequently occurs,
Each time, the steering characteristic of the vehicle changes, and the driver is confused.

Conventionally, in Japanese Patent Laid-Open No. 58-211061,
A technique has also been proposed in which, when the return speed of the accelerator pedal is a rapid return speed equal to or higher than a set speed, the shift pattern is switched to another pattern and the shift control is performed based on this.

However, in this technology, when the shift pattern is changed according to the change state of the engine load, even if the change speed of the engine load is faster than the reference, the shift pattern is simply switched to another pattern, and the shift pattern change amount is changed. It is impossible to always match the engine load change speed with any engine load change speed, and it is not possible to solve the problem.

SUMMARY OF THE INVENTION The present invention proposes a shift pattern change technique capable of adjusting the shift pattern change amount so as to always match with any engine load change rate, and has as its first object to surely solve the above-mentioned problem. In addition, we propose a gear shift pattern change technology that can adjust the gear shift pattern change amount so that it always matches with any engine load change rate and steering angle. The second purpose is to solve the problem.

(Means for Solving the Problem) For the first object of the first invention, as shown in the concept of FIG. 1 (a), the vehicle speed detected by the vehicle speed sensor 1 and the engine load detected by the engine load sensor 2 In the automatic transmission 4 in which the gear shift control means 3 determines the gear position in accordance with the predetermined gear shift pattern, the gear position detection means 5 for detecting the selected gear position of the automatic transmission 4, and the selected gear position and The acceleration setting means 6 for setting the reference acceleration of the vehicle based on the vehicle speed and the engine load, the acceleration calculation means 7 for calculating the actual acceleration of the vehicle based on the signal from the vehicle speed sensor 1, and the actual acceleration and the reference acceleration are compared. Comparing means 8 for calculating an acceleration deviation by means of a load change rate calculating means 9 for calculating an engine load change rate based on a signal from the engine load sensor 2; A shift for determining a shift line change amount in accordance with the acceleration deviation obtained by the stage 8 and the change rate of the engine load obtained by the load change rate calculation means 9, and changing the shift line of the shift pattern by the shift line change amount. Pattern changing means 10
And is provided.

Further, for the second object of the second invention, as shown in the concept of FIG. 1 (b), the gear shift control means 3 operates in accordance with the vehicle speed detected by the vehicle speed sensor 1 and the engine load detected by the engine load sensor 2. In an automatic transmission 4 configured to determine a gear position according to a planned gear shift pattern, a gear position detection means 5 for detecting a selected gear position of the automatic transmission 4, and a vehicle position based on the selected gear position, the vehicle speed, and the engine load. Acceleration setting means 6 for setting a reference acceleration, acceleration calculation means 7 for calculating the actual acceleration of the vehicle based on the signal from the vehicle speed sensor 1, and comparison means for calculating the acceleration deviation by comparing the actual acceleration and the reference acceleration. 8, a load change rate calculation means 9 for calculating the change rate of the engine load based on the signal from the engine load sensor 2, and a steering angle sensor 11 for detecting the steering angle of the vehicle. The shift line change amount is determined according to the acceleration deviation obtained by the comparison means 8, the engine load change rate obtained by the load change rate calculation means 9 and the steering angle detected by the steering angle sensor 11, and the shift line change amount is determined. The shift pattern changing means 10 for changing the shift line of the shift pattern by the line change amount is provided.

(Operation) In the first aspect of the invention, the means 6 sets the reference acceleration of the vehicle which should be obtained based on the gear position detected by the means 5, the vehicle speed detected by the sensors 1 and 2, and the engine load. The comparing means 8 determines the road surface gradient from the acceleration deviation between the reference acceleration and the actual acceleration calculated by the means 7, and the means 10 changes the road surface gradient (acceleration deviation) and the engine load calculated by the means 9. The shift line change amount is determined according to the ratio, and the shift line of the shift pattern is changed by this change amount.

Therefore, the change amount of the shift pattern takes into consideration not only the road gradient but also the rate of change of the engine load, and it always matches these, and the shift is repeated on an uphill road with a lot of carps, which makes passengers feel uncomfortable. It is possible to surely solve the above problems such as giving

In the second aspect of the invention, the change amount of the shift pattern is determined in consideration of the steering angle detected by the sensor 11 by the means 10. Therefore, the change amount of the shift pattern can be matched with the steering angle, and the above-mentioned problem that the steering characteristic is changed due to the shift during the sudden turn can be solved.

(Example) Hereinafter, the Example of this invention is described in detail based on drawing.

FIG. 2 is a functional block diagram showing an embodiment of the device of the present invention. In the figure, 21 is an engine, 22 is an automatic transmission, 23 is a propeller shaft, 24 is a final reduction gear, and 25 is a left / right drive wheel. Show. The output of the engine 21 is controlled by the throttle valve 26, and this output is transmitted to the drive wheels 25 via the automatic transmission 22, the propeller shaft 23, and the final reduction gear 24, so that the vehicle can travel.

The shift control of the automatic transmission during traveling is performed as follows.
That is, 27 is a vehicle speed sensor, 28 is an engine load sensor, the vehicle speed sensor 27 detects the output rotation of the automatic transmission to detect the vehicle speed V, and the engine load sensor 28 is the opening degree of the throttle valve 26 (slotter opening degree). ) Detect TH. Two
Reference numeral 9 denotes a shift control unit. Basically, that is, when the shift pattern changing unit 30 does not instruct to change the shift pattern, the sensor 27 is operated in accordance with the normal shift pattern shown in FIG. , 28 based on the vehicle speed V and the throttle opening TH detected by the automatic transmission 22.
Shift control.

The shift pattern is changed as follows. The actual acceleration calculator 32 time-differentiates the vehicle speed V detected by the sensor 27 to calculate the actual acceleration α _{R of the} vehicle. On the other hand, the reference acceleration calculation unit 33 should naturally obtain a vehicle on a flat road from the vehicle speed V and the throttle opening TH detected by the sensors 27 and 28 and the gear position of the automatic transmission 22 determined by the shift control unit 29. The reference acceleration α _{S of} is calculated. Acceleration comparison unit 34
Is a road surface gradient determined by what the actual acceleration α _R is in comparison with the reference acceleration α _S, that is, what α _S −α _R is, and the result is used to change the shift pattern. Supply to the department. On the other hand, the engine load change rate calculation means 35 determines what ratio the change amount of the throttle opening (engine load) detected by the sensor 28 per unit time is to the throttle opening before the change or the maximum throttle opening. Is calculated and input to the shift pattern changing unit 30. The shift pattern changing unit 30 uses the road surface gradient determined by the acceleration comparing unit 34 and the engine load change rate calculating unit 3
According to the ratio calculated in step 5, the shift pattern storage unit 3
The normal change pattern stored in 1 is changed by a predetermined amount. When the shift pattern is changed in this manner, the shift control unit 29 performs the shift control according to the changed shift pattern.

Such a function can be obtained by, for example, the microcomputer shown in FIG. This microcomputer includes a central processing unit (CPU) 40, a read only memory (ROM) 41, and a random access memory (RAM).
42, an input / output interface circuit (I / O) 43,
A normal unit composed of a crystal oscillator 44 is provided, and the vehicle speed sensor 27 and the engine load sensor 28 are provided on the input side of the I / O.
The automatic transmission 22 on the output side,
Connect various shift solenoids that control the shift control by turning them on and off.

The microcomputer executes the control program of FIG. 4 on the basis of the vehicle speed V and the throttle opening TH detected by the sensors 27 and 28 to determine the ON / OFF combination (shift signal G) of the various shift solenoids, and the automatic shift is performed. The gear position of the machine 22 (first speed to third speed in this example) is determined. This control program is repeated every fixed time (for example, 10 msec), and first, in steps 50 and 51, the sensors 27 and 28 are used.
The vehicle speed V and the throttle opening (engine load) TH are read based on the signal from, the selected gear position GEAR of the automatic transmission 22 is read from the speed change signal G in the next step 52, and the previous step of the vehicle speed V is read in step 53. The actual acceleration α _{R of the} vehicle is calculated by dividing the difference between the read value and the read value this time by the calculation interval ΔT of the control program. In the next step 54, the reference acceleration α _{S of the} vehicle, which should be obtained in the present driving condition on a flat road, is set. In this setting, table data shown below for each gear position stored in advance (however, the following table shows only the case of the third speed). Based on the gear position GEAR, the vehicle speed V and the throttle opening TH, the reference acceleration α _S is tabletop-up.

Next, in step 55, in order to compare the actual acceleration α _R and the reference acceleration α _S , the deviation Δα (Δα = α _S −α
_R ) is calculated and used as a material for determining the road surface gradient. In the next step 56, the amount of change ΔTH from the previous read value TH _n-1 to the current read value TH _{n of} the throttle opening TH is calculated. This change amount Δ
TH becomes negative as the throttle opening increases and becomes positive as the throttle opening decreases. In step 57, the slot opening change rate ΔTH per unit time (ΔT) is divided by the maximum slot opening TH _max to calculate the slot opening change rate. In step 58, this change rate is calculated in step 58. Add to the rate of change. This addition means that the tendency of the change rate of the throttle opening is grasped, and for example, the sum of the change rates of the throttle opening for five times. Is obtained.

In the next step 59, shift pattern change control is executed as follows. The ROM 41 (see FIG. 3) has a flat road gearshift pattern (however, shown by the solid line in FIG. 5 corresponding to FIG. 12).
Table data such as the following table corresponding to the upshift transmission line is shown.

The table data in shift vehicle speed V ₁₂ -1~V ₁₂ -8 and V ₂₃ -1~V ₂₃ -8 and data for each Surotsutoru opening segment TH ₁ to TH _8, in the vehicle speed V is V ₁₂ -1 or less the first speed, V ₁₂ -i~V
_This means that the second speed should be set between _23- i and the third speed should be set at V23-i or higher. The speed change pattern is changed based on the speed change pattern for flat roads. Therefore, in step 59, the speed change vehicle speed is first determined from this table data based on the slot opening TH.
It reads the V ₁₂ -i and V ₂₃ -i. Next, as shown in FIG. 6, as the previous period acceleration deviation Δα (road surface gradient) increases, the sum of the throttle opening change rates also increases. Shift line change amount set to increase as
Sum of acceleration deviation Δα and slot change rate from table data of V Based on the above, the shift change amount ΔV is navel-locked up. Then, the speed of the shifting vehicle with the table-up as described above.
This shift line change amount ΔV is added to V ₁₂ -i and V ₂₃ -i,
This completes the change of the shift pattern. Thus, the shift pattern is changed from the one shown by the solid line in FIG. 5 to the one shown by the dotted line on the high vehicle speed side. Incidentally, when the shift line change amount ΔV is 0, the shift pattern is naturally shown by the solid line in FIG.

Since the description is complicated, only the upshift gearshift pattern will be described here. However, it goes without saying that the downshift gearshift pattern can also be modified in the same manner.

At the next step 60, the gear position GEAR (NEW) is selected based on the changed gear shift pattern. In this selection, the gear position to be applied is selected in comparison with the vehicle speed V read in step 50 and the transmission vehicle speed changed in step 59. In the next step 61, the gear position GEAR (NEW) thus selected is compared with the gear position GEAR read in step 52, and the comparison result is GEAR = GEAR.
In step 62, check whether it is (NEW) or not.
If so, the current gear position is maintained by terminating the control as it is. If not, the automatic transmission 22 shifts the shift signal G (see FIG. 3) to the selected gear position at step 63. Change and end control.

7 to 9 show another embodiment of the device of the present invention. In this embodiment, as shown in FIGS. 7 and 8, a steering angle sensor 45 is added to the above embodiment. This sensor detects the steering wheel rotation angle (steering angle) θ of the vehicle and outputs a corresponding signal, and supplies this signal to the shift pattern changing unit 30 as shown in FIG. 7. Considering not only the road surface gradient determined by the shift pattern changing unit 30 and the acceleration comparison unit 34 and the throttle opening change rate calculated by the engine load change rate calculation unit 35, but also the steering angle θ detected by the sensor 45 is considered. The normal flat road shift pattern stored in the pattern storage unit 31 is changed by a predetermined amount.

Therefore, the steering angle sensor 45 is connected to the input side of the I / O 43 as shown in FIG. 8, and the microcomputer shown in the same figure executes the control program shown in FIG. 9 to change the shift pattern and follow the shift pattern. The gear shift shall be performed. In FIG. 9, the steps corresponding to the steps in FIG. 4 are indicated by the same reference numerals, and only the portions having different execution contents will be described below.

That is, add step 64 between steps 52 and 53,
Here, the steering angle θ is read, and the change of the shift pattern in step 59 is executed in consideration of the steering angle θ as follows. That is, during deceleration operation on a sharp curve that makes a sharp turn while sharply reducing the throttle opening, that is, the sum of the change rates of the throttle opening. Is positive and the steering angle θ is large, it is recognized that it is preferable not to upshift even if the throttle opening is decreased in terms of engine braking effectiveness and acceleration after turning. , The sum of the throttle opening change rates as shown in Fig. 10 to prevent upshifting under these conditions. From the table data of the shift line change amount change parameter p set so as to increase as the steering angle θ increases. First, the shift line change amount parameter P is table-up based on .theta. Next, as shown in FIG. 11, the shift line is changed from P and Δα on the basis of the table data of the shift line change amount ΔV set so as to increase as the parameter P increases and as the acceleration deviation Δα (road surface gradient) increases. Amount ΔV
To make a table. Then proceeds to only the high speed side this ΔV shift vehicle speed V ₁₂ -i and V ₂₃ -i in the same manner as the above-described example, to complete the shift pattern changes at step 59.

Therefore, in this example, the parameter P is the sum of the slot opening change rates. And the steering angle θ, the shift line change amount ΔV determined by this parameter and the acceleration deviation Δα is the acceleration deviation Δα and the throttle opening change rate. Not only the steering angle θ is also taken into consideration.

(Effects of the Invention) Thus, the first invention having the example configuration of FIGS. 2 to 4 is not limited to the acceleration deviation (road surface gradient) based on the result of comparison between the actual acceleration α _R and the reference acceleration α _S , but also the engine. The shift line change amount ΔV is determined in consideration of the load change rate ΔTH / TH _max , and the shift line of the shift pattern is changed by this change amount. Based on the road surface gradient) and the engine load change rate, these values are always matched to these, and the above-mentioned problems such as causing discomfort to the occupants due to repeated shifts on uphill roads with many curves can be eliminated more reliably. .

The second invention, which allows the configuration of FIGS. 7 to 9, is
In addition to the first aspect of the invention, since the steering angle θ is also used as a material for determining the shift line change amount ΔV, the shift pattern change amount always matches the steering angle. It is possible to eliminate the above-mentioned problems such as the occurrence of a gear shift and a change in steering characteristics.

[Brief description of drawings]

1 (a) and 1 (b) are conceptual diagrams of the shift control device of the present invention, FIG. 2 is a functional block diagram showing one embodiment of the present invention device, and FIG. 3 is a diagram of a microcomputer used in the same example. A block diagram, FIG. 4 is a flow chart showing a control program of the same microcomputer, FIG. 5 is a diagram showing a shift pattern before and after being changed by the device of the present invention, only for an upshift shift line, and FIG. 4 to 4 are characteristic diagrams of change of shift line change amount, and FIGS. 7 to 9 are functional block diagrams and block diagrams similar to FIGS. 2 to 4 showing another example of the present invention. FIG. 10 is a diagram showing a change characteristic of the shift line change amount change parameter in the same example, FIG. 11 is a change characteristic diagram of the shift line change amount in the same example, and FIG. 12 is a normal shift pattern. It is a diagram showing. DESCRIPTION OF SYMBOLS 1 ... Vehicle speed sensor, 2 ... Engine load sensor, 3 ... Shift control means, 4 ... Automatic transmission, 5 ... Gear position detection means, 6 ... Acceleration setting means, 7 ... Acceleration calculation means, 8 ...... Comparison means, 9 …… Load change rate calculation means, 10 …… Shift pattern changing means, 11 …… Steering angle sensor, 21 …… Engine, 22 …… Automatic transmission, 23 …… Propeller shaft, 24 …… Final reducer, 25 …… Drive wheel, 26 …… Slottle valve, 27 …… Vehicle speed sensor, 28 …… Engine load sensor, 29 …… Shift control section, 30 …… Shift pattern change section, 31 …… Shift pattern Storage unit, 32 ... Actual acceleration calculation unit, 33 ... Reference acceleration calculation unit, 34 ... Acceleration comparison unit, 35 ... Engine load change rate calculation unit, 40 ... Central processing unit, 41 ... Read-only memory, 42 …… random access memory, 43 …… input / output interface Circuit, 44 …… Crystal oscillator, 45 …… Steering angle sensor

Claims (2)

[Claims] 1. An automatic transmission in which a shift control means determines a gear position according to a planned shift pattern in accordance with a vehicle speed detected by a vehicle speed sensor and an engine load detected by an engine load sensor. Gear position detecting means for detecting a selected gear position, acceleration setting means for setting a reference acceleration of the vehicle from the selected gear position, the vehicle speed and the engine load, and the actual acceleration of the vehicle is calculated based on a signal from the vehicle speed sensor. An acceleration calculation means, a comparison means for calculating an acceleration deviation by comparing an actual acceleration and a reference acceleration, a load change rate calculation means for calculating a change rate of an engine load based on a signal from the engine load sensor, The shift line change according to the acceleration deviation calculated by the comparison means and the change rate of the engine load calculated by the load change rate calculation means. Determining the amount, the shift control apparatus for an automatic transmission characterized by comprising providing a shift pattern changing means for changing the shift lines of only the shift pattern gear shifting line changed amount. 2. An automatic transmission in which a shift control means determines a gear position according to a predetermined shift pattern in accordance with a vehicle speed detected by a vehicle speed sensor and an engine load detected by an engine load sensor. Gear position detecting means for detecting a selected gear position, acceleration setting means for setting a reference acceleration of the vehicle from the selected gear position, the vehicle speed and the engine load, and the actual acceleration of the vehicle is calculated based on a signal from the vehicle speed sensor. An acceleration calculation means, a comparison means for calculating an acceleration deviation by comparing an actual acceleration and a reference acceleration, a load change rate calculation means for calculating an engine load change rate based on a signal from the engine load sensor, The steering angle sensor for detecting the steering angle of the vehicle, the acceleration deviation obtained by the comparison means, and the load change rate calculation means And a shift pattern changing means for determining a shift line change amount according to a rate of change of engine load and a steering angle detected by the steering angle sensor, and changing the shift line of the shift pattern by the shift line change amount. A shift control device for an automatic transmission characterized by the above.