JPS6145160A - Speed change control device of automatic speed change gear - Google Patents

Abstract

PURPOSE:To heighten the accuracy of shift pattern change control by changing a shift pattern according to an output torque and an engine load. CONSTITUTION:An engine load detection means 3 is coupled to an engine 1, and torque detection means 4 is coupled to an output shaft of an automatic speed change gear 2, so that outputs from both detection means 3, 4 are input to shift pattern change means 5 to change a shift pattern according to an output torque and an engine load. Thus, only a required speed change line can be shifted to the high car velocity side or low car velocity side only in a required engine load region, so that a shift pattern change control can be made with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a shift control device for an automatic transmission for a vehicle.

(Conventional Technique wI) A shift control device for an automatic transmission generally adjusts the required gear based on a predefined shift pattern as shown in FIG. The position is determined by 15, and if this differs from the actual gear position, it functions to automatically shift the automatic transmission to the requested gear position.

However, shift patterns are stipulated to provide good acceleration and fuel efficiency based on specific vehicle conditions (vehicle weight, etc.) and driving conditions (degree road slope, etc.), and shift patterns are based on driving conditions and the driver's will. It cannot be sufficiently reflected in control. In particular, since the shift pattern is determined assuming driving on a flat road, when driving downhill, the 1←2 and 2←8 downshift shift lines (first
(see the dotted line in figure 0) is located at a lower vehicle speed than necessary and the high gear is maintained until the vehicle speed is low, making it difficult to obtain engine braking. It was a hassle to have to rely on operations such as fixing the gear to a low gear.

In order to solve this problem, the
A shift pattern changing technique as shown in the above publication was proposed. This shift pattern change technology changes the shift line according to the road surface slope and engine temperature, that is, when driving on a climbing road or a descending road, or when the engine is low temperature, the shift line is shifted to a higher vehicle speed side than when driving on a flat road or when the engine temperature is high. It was designed to make it move.

(Problem to be solved by the invention) However, with this technology, shifting the shift line toward higher vehicle speeds throughout the entire engine load range may cause unnecessary shifts in the shift line or unnecessary engine load. The shift pattern change control lacks precision due to deviations in the shift line portion of the area, which is impractical, and it is not possible to perform control such as changing the amount of deviation of the 1-shift line according to conditions. Ta.

(Means for Solving the Problems) In order to solve the first two problems, the first aspect of the present invention configures a speed change control device for an automatic transmission as shown in FIG. 1(a). In other words, the power from the engine 1 automatically shifts the gear 1! !
2, in which the automatic transmission changes gears according to a shift pattern defined by vehicle speed and engine load, engine load detection means 3 for detecting the engine load, and output torque of the automatic transmission. The present invention includes a torque detection means 4 for detecting torque related to the engine load, and a shift pattern changing means 5 for changing the shift pattern according to the torque and the engine load.

In addition, in order to solve the latter problem, the second invention of the present invention, as shown in FIG. In a vehicle that changes gears according to a shift pattern defined by , and a shift pattern changing means 5 that changes the shift pattern according to the engine load, torque, and load.

(Function) In the first invention, the 1 shift pattern changing means 5 changes the shift line to be changed (when the engine load detected by the means 8 and the torque detected by the means 4 are within the range where the shift line should be changed). Since only the part in the specific engine load range is changed, the first two problems can be solved.

Further, in the second invention, the shift pattern changing means 5' includes:
The acceleration of the vehicle detected by the means 6 is also input, and the change value of the variable Ms is changed accordingly, so that the latter problem can also be solved.

(Example) Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 2 shows a power train of a vehicle equipped with an automatic transmission controlled by the transmission control device of the present invention, in which 10 is an engine, 11 is an automatic transmission, 12 is a drive wheel, and 1
8 is a differential gear. Automatic shifting! fIl
1 consists of a torque converter 14, a transmission gear train 15, various transmission control solenoid valves 1B, and a transmission control circuit 17 that constitutes the main parts of the present invention, and converts the power from the engine 10 into the torque converter 14, transmission gear train 15, and transmission. The vehicle can be driven by transmitting the signal to the wheels 12 via the output shaft 1B and the differential gear 18.

During this running, the speed change gear train 15 automatically selects the optimum power transmission train (gear position) by the speed change control circuit 17 via the various speed change control 1 magnetic valves 16.

The speed change fi1 circuit 17 includes a throttle opening sensor 19 that detects the throttle opening (engine load) of the engine 10.
The signal from the gear position sensor 20 detects the current gear position depending on which of the various speed change M control solenoid valves 16 is operated.The signal from the gear position sensor 20 detects which range the shift lever of the GS automatic transmission 1111 is set to. Signal L1 from the shift lever position sensor 21 to detect the rotation speed (vehicle speed) of the shift lever output MlB Signal v from the vehicle speed sensor 22
1 and a signal T from a transmission output torque sensor 23 that detects the torque of the transmission output shaft 18, respectively, and the gear change control described later is executed based on these input information.

Although each of the above-mentioned sensors 19 to 28 may be of a well-known type, the transmission output torque sensor 2B in particular is described in Japanese Patent Publication No. 8
Using something like the one shown in Publication No. 5-12447,
Normally, a C positive (7) # proportional voltage is output as shown in Figure 3 (a), and during engine braking, a negative torque proportional voltage is output as shown in Figure 8 (b). .

The shift control circuit 1 includes a shift pattern storage section 24, a gear position selection section 25, a comparison section 26, and a shift pattern as shown in FIG. It shall consist of a changing section 27. The shift pattern storage unit 24 stores a shift pattern as shown in FIG.
['H.

Based on the selection range L1 vehicle speed V, the stored data in the storage unit 24 (
The comparator 2B reads out the gear position from the shift pattern shown in FIG. , OFF are kept as they are to maintain the current gear position, and if they do not match, the tm valve 18 is turned on or off to change gears to the read gear position.

The shift pattern changing unit 27 determines whether or not it is necessary to change the shift pattern from the throttle opening TH and transmission output torque T detected by the sensor 1912B, and if necessary, determines which shift line to change, For example, as shown in FIG. 9, the 1←2.2←8 shift line in FIG. 2 is shifted to the high vehicle speed side, such as B12°B1111, in a specific throttle opening range.

Thereafter, until the shift pattern is returned to that shown in FIG. 10, the above-described shift control is performed based on this changed shift pattern.

To obtain such control, the speed change control circuit 17 executes the control programs shown in FIGS. 5 and 6. FIG. 5 shows the main routine. When the routine is started at step 80 when the engine is started, the vehicle speed V is first read in step 81, and the throttle hearing TH is read in the next step 82. In the next step 83, it is determined whether or not the throttle opening IITI (is less than the set value TH8 (see Fig. 9), and TH
If ≧TH8, the shift pattern is not changed and normal gear shifting is performed in accordance with the shift pattern shown in FIG. 10 as follows.

That is, in this case, step 84 is first selected, and it is determined here whether the shift pattern change flag OHGF L G, which becomes 1 during the shift pattern change, is 1. CHGF
LG ■ If it is 1, that is, if the shift pattern was being changed last time, in step 35, the shift pattern is returned from the changed state to the pattern shown in FIG. 10? ,,0H in next step 3B
GFLG Is it reset to TtO and the shift pattern is not being changed? As shown, in the next step 8 step 1
Based on the shift pattern shown in Figure 0, the gear position is read from the throttle opening TH1 vehicle speed V and shift lever position. Note that if step 34 determines that 0HGFLG -1 is not present, that is, if it determines that the previous shift pattern has not been changed, step 85.38'E- is skipped and step 87 is executed.

Thereafter, the control proceeds to step 88, where the read gear position and the currently selected gear position G are compared, and if they match, the control returns to step 31.

If the gears are not changed and the two do not match, step 89
After changing the on/off P of the various speed change control IE solenoid valves 6 and changing the speed to the read gear position, the control is started at step a.
Return to 1.

By the way, if it is determined in step 88 that TH<TH8, the control proceeds to step 40, where the shift pattern is changed, and then the control proceeds to step 87. The process in step 40 is started in step 41 by the subroutine shown in FIG. First, in step 42, the transmission output torque T is read, and in the next step 43, it is determined whether this torque T is negative or not, that is, whether or not the vehicle is running while applying the engine brake as shown in FIG. 8(b). do. If not, that is, during steady or accelerated driving as shown in 3rd rgJ(a), the shift pattern is not changed even if it is determined to be TH (TH3) in step 88 in FIG. 4) or 44.47, and step 47 returns control to step 87 in FIG. The contents of steps 4.4 to 46 are the same as step 8 in Figure 5.
Same as 4-8B.

If it is determined in step 43 that the torque T is negative, that is, if the vehicle is running with the engine brake applied as shown in FIG. 3(b), the control proceeds to step 148 to change the shift pattern. Let's do it.

In making this change, first select the shift line to be changed, and in this example, set the shift line to 1←2 shift line and 2←8 shift line as shown in Fig. 9 (the dotted lines correspond to the corresponding lines in Fig. 10). (equivalent to the gear shift line). 1 These shift lines are shown in Fig. 9 as dot-dashed line B1□
l As shown by BQ8, the vehicle speed is shifted by a predetermined amount to the high vehicle speed side only in the throttle opening range below TH8. At step 49, C! indicates that the shift pattern is being changed. HGFLG is set to 1, and in the next step 47, control is returned to step 8 in FIG.

Steps 87 to 89 of the fifth H execute the above-described shift control, but since the shift pattern has now been changed as described above, the gear position read out in step 37 is determined by this changed shift pattern. Therefore, while driving while applying engine braking, a low gear will be selected in a relatively high vehicle speed range, and sufficient engine braking can be obtained, eliminating the need to rely on manual operation of the foot brake or shift lever. The vehicle can be decelerated in a predetermined manner without any troublesome operations.

The reason why the shift pattern is changed only when the throttle opening degree TH is less than the set value TH3 is as follows. That is, while driving with the pedal down (T<O), the driver may not fully close the throttle opening 9T)I, but may maintain it at a slightly lower opening while driving while adjusting the engine brake. In this case, if the shift pattern is unconditionally changed as described above when T<O, an unnecessary 1←2 or 2←8 downshift will be performed, and the driver will have to drive while increasing or decreasing the engine brake as described above. This is because it becomes impossible.

FIG. 7 shows another example of the present invention, in which the vehicle
The signal α from the acceleration sensor 2B that detects the acceleration is also input to the shift control circuit 1W, and the shift pattern changing unit 27 responds to the vehicle acceleration α, and when this is less than the set value, the shift pattern is indicated by B121B28 in FIG. Change the shift pattern in the same way as in the example above, and if the value exceeds the set value, change the shift pattern to C in the figure.
, C is shifted to the higher vehicle speed side by <-i. The purpose of this is to determine whether the engine brake is effective when coasting (coasting on a flat road) or when driving downhill, based on the acceleration α of the vehicle, and if this acceleration is less than a set value. The aim is to make the control more precise in the latter case, in which the acceleration exceeds the set value, by shifting the shift line further toward the higher vehicle speed side than in the former case, in which the acceleration exceeds the set value.

Note that acceleration α can also be obtained by time differentiation of vehicle speed ■,
In this case, the acceleration sensor 2B is unnecessary, which is advantageous.

In this example, the variable i control circuit 17 executes the control programs shown in FIGS. 5 and 8. FIG. 5 shows a main routine executed as described above, and FIG. 8 shows a subroutine for shift pattern changing processing corresponding to FIG. 6. In this example, steps 50 to 52 are added to this subroutine.

In step 50, the acceleration α of the vehicle is read, and in the next step 51, the acceleration α, which should be obtained on a flat road from this acceleration α, running resistance Df1 on a flat road, final gear ratio r1, transmission output torque T1, vehicle image quality 1 m, and drive wheel radius R. Reference (setting) acceleration change αS″4r for transmission output torque T: Calculated by the following equation.

r-T/R-Df α = -11111111 - S m In the next step 52, the ratio of the acceleration α to the set acceleration qα6, that is, the acceleration ratio A, a/aS is determined. In the next step 48, shift lines to be changed are selected as shown in FIG. 9, and when the acceleration ratio A is negative and its absolute value is below a predetermined value in the throttle opening region below THS, The vehicle is shifted toward higher vehicle speeds as shown by B and B in Figure 9, and when the acceleration narrowing ratio A is negative and its absolute value is greater than a predetermined value, it is shifted further toward higher vehicle speeds as shown by C and C in the same diagram. Change the shift pattern so that

In this way, when the vehicle is traveling on a steeply descending road where the acceleration α increases, the shift line that should be changed is shifted to the higher vehicle speed side, and the effectiveness of the engine brake can be matched to the slope of the descending road.

Therefore, while traveling downhill, the driver can shift the vehicle without having to operate the foot brake or shift lever, and can also avoid the inconvenience of having to increase the throttle opening due to excessive engine braking.

(Effects of the Invention) As described above, the shift control device of the present invention has TfR configured to change the shift pattern according to the engine load and the transmission output torque, so that only the necessary shift line is changed in the necessary engine load range. The shift pattern can be shifted to the high vehicle speed side or the low vehicle speed side, and shift pattern change control can be performed with high precision.

In addition, by adopting the M configuration that controls the change of the shift pattern according to the acceleration of the vehicle, the shift amount of the shift line can be adjusted under the condition (
The shift pattern can be changed in accordance with the road surface gradient), and the shift pattern change control can always be made to match the conditions, making it possible to change the shift pattern more precisely.

[Brief explanation of the drawing]

FIGS. 1(a) and (b) are conceptual diagrams of the transmission control device of the present invention, and FIG. 2 is a system diagram showing a third embodiment of the device of the present invention. Figure 4 is a functional block diagram of the gear shift control circuit used in the same example; FIG. 6 is a flow chart showing a control program of the same speed change control circuit, FIG. 7 is a functional block diagram similar to FIG. 4 showing another example of the present invention, and FIG. 8 is a flow chart showing the same example of the speed change control circuit. FIG. 9 is a flowchart of a shift pattern change processing routine to be executed, and FIG. 9 is a diagram 1 showing an example of a shift pattern change by the apparatus of the present invention. FIG. 10 is a diagram showing a shift pattern of a general automatic transmission. 1.10...Engine 2,11...Automatic transmission 3...Engine load detection means 4...Torque detection means 5...Shift pattern changing means 6...Acceleration detection means 12... Drive wheel 18...
Differential gear 14... Torque converter 15... Speed change gear train 16...
・Various speed change control solenoid valves 17...speed change control circuit 18...F speed machine output shaft 19
... Throttle opening sensor (engine load detection means) 20 ... Gear position sensor 21 ... Shift lever position sensor 22 ... Vehicle speed sensor 2B ... Transmission output torque sensor (torque detection means)
24... Shift pattern storage section 25... Gear position selection section 26... Comparison section 27...
・Shift pattern changing unit 28... Acceleration sensor (acceleration detection means). Fig. 1 (a) (b) Fig. 5 Fig. 6 Fig. 8 Fig. 9

Claims (1)

[Scope of Claims] 1. In a vehicle that is driven by power from an engine via an automatic transmission, and the automatic transmission changes gears according to a shift pattern defined by vehicle speed and engine load, An engine load detecting means for detecting an engine load, a torque detecting means for detecting a torque related to an output torque of an automatic transmission, and a shift pattern changing means for changing the shift pattern according to the torque and the engine load. A speed change control device for an automatic transmission characterized by: 2. In a vehicle that is driven by power from an engine via an automatic transmission, and the automatic transmission changes gears according to a shift pattern defined by vehicle speed and engine load, engine load detection means for detecting the engine load. a torque detection means for detecting torque related to the output torque of the automatic transmission; an acceleration detection means for detecting acceleration of the vehicle; and a shift pattern changing means for changing the shift pattern according to the engine load, torque, and acceleration. A speed change control device for an automatic transmission, comprising: