JPS59222656A - Control device in automatic transmission - Google Patents

Abstract

PURPOSE:To enhance the running ability and fuel consumption, by carrying out the control of speed change in accordance with equi-output curves which are parted from a turbine rotational speed v.s. generated output power characteristic curve at a fixed fuel consumption rate by a range of variations in the rotational speed of a torque converter output shaft, which range is obtained in accordance with the difference between gear ratios of adjacent speed shift stages. CONSTITUTION:Output signals from a turbine rotational speed sensor (b) and an engine load sensor (g) are compared with a shift-up speed changing curve and a shift-down speed changing curve that are set on the basis of a low speed side equi-output power curve A and a high speed side equi-output power curve B which are parted from each other by a range (a) of variations in the rotational speed of a torque converter (a), which range is culculated in accordance with the difference between gear ratios of adjacent speed shift stages in each of plurality of curves indicating a turbine rotational speed v.s. generated output characteristic curve obtained when the fuel consumption rate of the engine is fixed at each value. Therefore, whether shift-down or shift-up is necessary or not is determined. When judgement is made that it is necessary, a shift-down discriminating means (i) or a shift-up discriminating means (j) is operated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a control device for an automatic transmission, and more particularly to a control device for an automatic transmission used in a traveling vehicle such as an automobile. ``Prior Art Automatic transmissions currently in general use are constructed by combining a torque converter and a multi-stage gear type transmission mechanism having a gear mechanism such as a planetary gear mechanism. Normally, a hydraulic mechanism is used, and the hydraulic circuit is switched by a mechanical or electromagnetic switching valve, and the friction elements such as brakes and clutches associated with the multi-gear transmission mechanism are actuated accordingly to control the engine power transmission system. The gears are shifted to obtain the required gear position.

When switching the hydraulic circuit using an electromagnetic switching valve,
An electronic device detects when the vehicle's running state exceeds a predetermined shift line, and a signal from this device selectively operates an electromagnetic switching valve, which switches the hydraulic circuit to shift gears. However, in conventional systems, the above-mentioned shift line was determined using the vehicle speed-engine load characteristics as a control parameter, but since vehicle speed is a control parameter via the transmission, it differs for each gear. A shift line with a different pattern is required, which makes control complicated. In addition, since the engine load is detected by detecting the elottor opening degree, which is normally set in stages, if the above-mentioned shift line is stepped, this step-shaped shift line and the engine rotation speed - There are parts where the deviation between the torque characteristics, that is, the engine characteristics, becomes quite large. This is particularly noticeable when the quantized data used is coarse.

In order to eliminate the above-described drawbacks of the conventional apparatus, Japanese Patent Publication No. 56-44312 and other publications propose using the turbine speed-engine load characteristic as the parameter for determining the shift line. in this way,
Those that use the turbine speed-engine load characteristic as a control parameter do not use data via the transmission, so there is only one shift line, and even if the throttle opening etc. change, the turbine rotation will not fluctuate. Since it is relatively small and stable, the hysteresis between the shift amplifier shift line, downshift shift line, and lock amplifier cut line is small, and there is no restriction line such as a stall line, so there is freedom when setting the shift line. It has the advantage of having a large degree.

OBJECTS OF THE INVENTION The present invention provides a control device for an automatic transmission of the type that uses the turbine speed-engine load characteristic as a control parameter, which can improve running performance and fuel economy. The purpose is to provide the following.

Development of the invention and configuration of the invention Figure 1 shows the fuel flow rate i/H) of 7.8.10.14.
6.18.22.26.30 is a graph showing the turbine rotation speed-generated output (KW) characteristic when constant. As can be seen from Fig. 1, the fuel flow rate (
j2/H) is held constant and the turbine speed increases gradually, the generated output gradually increases until it reaches a certain peak value, and after that, it gradually decreases. In a line showing such characteristics, outputs such as those on the low-speed eaves side, which are separated by the rotational speed fluctuation range a of the output shaft of the torque converter calculated according to the difference in gear ratios of adjacent gears, and whose values are equal to each other, are Find the point a and the high rotation side equal output point A, connect the low rotation equal output point a on each line to obtain the low rotation eave side equal output curve A, and on the other hand, find the high rotation side equal output point A on each line. Knot,
Once the high rotation side equal output curve B is obtained, these equal output curves A
, B, it is possible to operate at a relatively high output even with a constant fuel flow M, that is, a constant fuel consumption rate.

Incidentally, the above-mentioned rotation speed fluctuation H is calculated by the following formula.

However, Tnd: turbine rotational speed at the downshift point, G;
Gear ratio, A: Difference in gear ratio between adjacent gears.

On the other hand, as shown in Figure 2, the horizontal axis represents the turbine rotation speed,
For example, the generated output is 30 at a fuel flow rate that satisfies the conditions explained in FIG.
Fuel flow rate 16I corresponding to KW and 15KW respectively! ,
/H13#/H is constant at each value, turbine rotation speed - throttle opening (engine i characteristic curve (shown by broken line)), and generated output corresponding to the above fuel flow rate (e.g. 30KW, 15KW) If we draw a turbine rotation speed-throttle opening (engine load) characteristic curve (indicated by a solid line and hereinafter referred to as the equal output curve) when is constant at each value, we obtain intersections a' and b'.Each intersection a ', b' are the points of the same fuel flow rate, that is, the fuel consumption rate in the case of equal generated output!And between these intersections a and b' is the torque converter determined by the difference in gear ratio of the change gear when changing gears. The intersection points a' and b' are equal to the points a and 2 shown in FIG.
It can be seen that these points are synonymous with and b. Therefore, if the engine is operated in the region between points a' and b' of the above-mentioned equal force curve, fuel consumption can be reduced, and in the region between the above points a' and b', the throttle opening Since this is near the inflection point which is the proportional limit of the generated output, driving in this region will result in good running performance. Therefore, in the present invention, lines A' and B' are formed by connecting the above-mentioned intersections a' and b' of each characteristic curve, and the speed change control is performed based on these lines A' and B'. .

That is, as shown in FIG. 3, the present invention includes a torque converter a connected to the output shaft of an engine, and a speed change gear mechanism b connected to the output shaft of the torque converter a.
, a speed change switching means C1 for switching the power transmission path of this speed change line gear mechanism and performing a speed change operation; a hydraulic active for operating this speed change switching means; and an electromagnetic means e for controlling the supply of pressure fluid to the motor; In an automatic transmission in which gear e is drive-controlled and shifts, a turbine rotation speed sensor f detects the output shaft rotation speed of a torque converter a, an engine load sensor g detects the engine load, and a fuel consumption rate is kept constant at each value. In each of the plurality of lines showing the turbine rotation speed vs. generated output characteristics when Shift down set based on the low rotation eave side equal output curve formed by finding the equal output points on the low rotation axis side and the equal output points on the high rotation side and connecting the equal output points on the low rotation axis side in each line. Storage means h that stores the shift line and the shift door/knob shift line set based on the one-rotation side equal output curve formed by connecting the high rotation side equal output points in each line.
, receives the output signal of the turbine rotation speed sensor f and the output signal of the engine load sensor g, compares these output signals with the downshift shift line, determines whether a downshift is required, and determines whether or not a downshift is required. Shift-down determining means i, which issues a shift-down command signal when
a shift-up determination means j that determines whether or not an upshift is required by comparing it with a knob shift line and issues a shift-up command signal if necessary; and a shift-down command signal of the shift-down determination means i and the shift-up command signal. The present invention is characterized in that it includes a drive means k which receives a shift-up command signal from the amplifier determining means j and drives and controls the electromagnetic means e based on these two command signals to automatically change gears.

In the automatic transmission control device of the present invention, which has a configuration that exceeds the effects of the invention, adjacent gear shift Determine the equal output point on the low rotation axis side and the equal output point on the plane rotation side, which are separated by the rotation speed fluctuation range of the output shaft of the torque converter calculated according to the difference in the gear ratio of the stages, and have equal values, and shift down. The shift line is set based on the low rotation eave side equal output curve formed by connecting the low rotation axis side equal output points on each of the above lines, and the shift amplifier shift line is
Since the settings are made based on the high-speed equal output curves for each of the above lines, and the shift control is performed based on these shift lines, the engine is always operated in the range where running performance and fuel consumption rate are good as described above. be able to.

EXAMPLE Hereinafter, a control device for an automatic transmission according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 4 is a diagram showing a cross section of a mechanical part of an automatic transmission incorporating a control device according to an embodiment of the present invention and a hydraulic control circuit.

Structure of automatic transmission The automatic transmission includes a torque converter/'jl'io, a multi-stage gear transmission mechanism 20, and an overdrive planet disposed between the torque converter 10 and the multi-stage gear transmission mechanism 20. It is composed of a gear transmission mechanism 50.

A torque converter 10 is connected to the engine output shaft 1.
A coupled pump 11 has a turbine 12 disposed opposite to the pump 11, and a stator 13 disposed between the pump 11 and the turbine 12, and a converter output shaft 14 is coupled to the turbine 12. . A lock-up clutch 15 is provided between the converter output shaft 14 and the pump 11. This lock-up clutch 15 is constantly pushed in the engagement direction by the hydraulic pressure circulating within the torque converter IO, and is held in the open state by the release hydraulic pressure supplied to the clutch 15 from the outside.

The multi-stage gear transmission mechanism 20 has a first-stage planetary gear mechanism 21 and a rear-stage planetary gear mechanism 22, and the sun gear 23 of the front-stage planetary gear mechanism 21 and the sun gear 24 of the rear-stage planetary gear mechanism 22 are connected by a connecting shaft 25. There is. The human power shaft 26 of the multi-stage gear transmission mechanism 20 is connected to the connecting shaft 25 via the front clutch 27 and to the internal gear 29 of the front planetary gear mechanism 21 via the rear clutch 28. Connection shaft 25 Zunawaji sun gear 23.2
A front brake 30 is provided between the transmission case 4 and the transmission case. The planetary carrier 31 of the front planetary gear mechanism 21 and the internal gear 33 of the rear planetary float mechanism 22 are connected to an output shaft 34 , and the planetary carrier 31 of the front planetary gear mechanism 21 is connected to the output shaft 34 .
A rear brake 36 and a one-way clutch 37 are provided between the planetary carrier 35 and the transmission case.

The overdrive planetary gear transmission mechanism 50 includes a planetary carrier 5 that rotatably supports a planetary gear 51.
2 is connected to the output shaft 14 of the torque converter IO, and the sun gear 53 is connected to an internal gear 55 via a direct coupling clutch 54. An overdrive brake 5 is provided between the sun gear 53 and the transmission case.
6 is provided, and an internal gear 55 is connected to the human power shaft 26 of the multi-stage gear transmission mechanism 20.

The multi-gear transmission mechanism 20 is of a conventionally known type and has three forward speeds and one rear speed, and a desired speed can be obtained by appropriately operating the clutches 27, 28 and brakes 30, 31.

When the overdrive planetary gear transmission 50 and the direct coupling clutch 54 are engaged and the brake 56 is released, the shaft 14
．． 26 are connected in a direct connection, and when the brake 56 is engaged and the clutch 54 is released, the shaft 14.26 is connected in overdrive.

Hydraulic Control Circuit The automatic transmission described above is equipped with a hydraulic control circuit as shown in FIG. This hydraulic control circuit has an oil pump 100 driven by an engine output shaft 1, and the pressure of hydraulic oil discharged from the oil pump 100 into a pressure line 101 is increased by a pressure regulating valve 102 and sent to a select valve 103. be guided. The select valve 103 is
1.2, D, , N, R, , P, and when the select valve is in the 1.2 and P positions, the pressure line 101 is connected to the ports a, b, and c of the valve 103. It goes through.

Boat a has an actuator 1 for operating the rear clutch 28.
04, and when the valve 103 is in the first position, the rear clutch 28 is held in the engaged state. It is also connected to the boat a near the left end of the 1-2 shift valve 110, pushing its spool to the right in the figure. Boat a is further transferred to the right side of the 1-2 shift valve 110 via the first line L1 and to the 2-3 shift valve via the second line L2.
3 to the right side of the shift valve 120 via the third line L3.
-4 shift valves 1: connected to the upper ends of 0, respectively. First, second and third drain lines DI, D2 and D3 branch from the eleventh second and third lines Ll, L2 and L3, respectively, and these drain lines DI, 1) 2, D3 are connected to eleventh second and third solenoid valves SLi SL2 and SL3 which open and close the drain lines DI, D2 and D3.

The above solenoid valves SLI, SL2, SL3 are connected to line l.
When excited while O1 and boat a are in communication,
Each train line D1. ．． D2 and D3 are closed, and as a result, the pressure inside the first, second, and third chambers is increased.

Boat B is the second Mikotoku valve■05 also has line 140
This pressure is connected via the valve 105.
It acts to push the spool downward in the figure. When the spool of the valve 105 is in the lower position, lines 140 and 141 communicate with each other, and hydraulic pressure is introduced into the locking side pressure chamber of the actuator 10B of the front brake 30 to hold the front brake 30 in the operating direction. The boat C is connected to the second lock valve 105, and this pressure valve 1
It acts to push the 05 spool upward. Additionally, boat C is connected to a 2-3 shift valve 120 via pressure line 106. This line 106 is the second
Solenoid valve SL2 of drain line D2 is energized,
The pressure in the second line L2 is increased, and this pressure increases the pressure in the second line L2.
-3 When the spool of shift valve 120 is moved to the left, it communicates with line 107. The line 107 is connected to the release side pressure chamber of the front brake actuator 108, and when hydraulic pressure is introduced into the pressure chamber, the actuator 108 operates the brake 30 in the release direction against the pressure of the engagement side pressure chamber. . The pressure in line 107 is also directed to actuator 109 of forward clutch 27, causing this clutch 27 to engage. The select valve 103 is 1
It has a boat d that leads to the pressure line 101 at the position, which is connected to the 1-2 shift valve 110 via line 112 and to the rear brake 3 via line 113.
6 actuator 114.

When the solenoid valves SLI and SL2 are energized by a predetermined signal, the 12 shift valve 110 and the 2-3 shift valve 120 move the spool to switch lines, thereby operating a predetermined brake or clutch. , 1-2 and 2-3 respectively. The hydraulic control circuit also includes a cantback valve 115 that stabilizes the hydraulic pressure from the pressure regulating valve 102, a vacuum throttle valve 116 that changes the line pressure from the pressure regulating valve 102 according to the magnitude of the intake negative pressure, and this throttle valve 116. An auxiliary throttle backup valve 117 is provided. Furthermore, the hydraulic control circuit of this example includes a 3-4 shift valve 130 and an actuator 1 to control the clutch 54 and brake 56 of the planetary float shift ta50 for overdrive.
32 are provided. The locking side pressure chamber of the actuator 132 is connected to the pressure line 101, and the pressure of the line 101 pushes the brake 56 in the engaging direction. Similar to the 1-2.2-3 shift valves 110 and 120, this 3-4 shift valve also moves downward when the solenoid valve SL3 is energized, and the pressure line 101 and line 122 are moved downward. Blocked, line 12
2nd floor is drained. As a result, the hydraulic pressure acting on the release side pressure chamber of the actuator 132 of the brake 56 disappears, and the brake 56 is actuated in the engaging direction, and the actuator 134 of the clutch 54 acts to release the clutch 54.

The hydraulic control circuit in this example includes a lock-up control valve 1.
33 is provided, and this one pull-up control valve 13
3 is connected to boat a of the select valve 103 via line L4. A drain line D4 branches off from this line 1.4 and is provided with a solenoid valve SL4, similar to the drain lines D1, I)2, D3. The lock-up control valve 133 is activated when the solenoid valve SL4 is energized.
! .

When the line D4 is closed and the pressure inside the line D4 increases, its spool is connected to lines 123 and 124.
When the line 124 is further drained, the lock-up clutch 15 is moved in the connecting direction.

In the above configuration, the operational relationship between each gear, the lock amplifier, and each solenoid, and the operational relationship between each gear and the clutch and brake are shown in the table below.

Table 1 Table 2 Electronic control circuit with microcomputer Next, referring to FIG. 5, an electronic control circuit 200 for controlling the operation of the hydraulic control circuit will be described.

The electronic control circuit 200 includes an input/output device 201, a random
It includes an access memory 202 (hereinafter referred to as RAM) and a central processing unit 203 (hereinafter referred to as CPU). The input/output device 201 includes an engine 204. A load sensor 207 detects the engine load from the opening degree of a throttle valve 206 provided in the intake passage 205 and outputs a load signal SL, and a load sensor 207 detects the rotation speed of the converter output shaft 14 and outputs a turbine rotation speed signal. Sensors for detecting running conditions, such as a turbine rotational speed sensor 209 that outputs ST, are connected, and the above-mentioned signals and the like are manually inputted from these sensors.

The input/output device 201 receives a load signal S from the sensor.
L, processes the turbine rotation speed signal S'F and stores it in the RAM20.
Supply to 2. The RAM 202 stores these signals SL and ST', and supplies data of these signals SL, ST, or others to the CPU 203 in response to instructions from the CPU 203. The CPU 203 reads out the turbine rotational speed signal ST according to the load signal SL according to a program adapted to the speed change control of the present invention, for example, the turbine rotational speed as shown in FIG. 5A.
Based on the upshift shift line LU and downshift shift line Ld determined based on engine load characteristics, a calculation is performed to determine whether or not a shift should be made. The downshift shift line Ld is determined based on the difference in gear ratio between adjacent gears in each of a plurality of lines showing the turbine rotation speed-generated output characteristics when the fuel consumption rate is constant at each value as described above. Output shaft of the torque comparator calculated accordingly - Find the low rotation eave side output point and the high rotation side output point that are separated by the rotation speed fluctuation range and have the same value, and calculate the low rotation output point on each line. It is set based on the low-rpm eaves-side equal-output curve A' shown in Figure 2, which is formed by connecting the shaft-side equal-output points, and the shift amplifier speed change line described above is based on the high-rpm equal-output curve A' in each of the above-mentioned lines. It is set based on the high rotation side equal output curve B' formed by connecting the equal output points on the side. The kickdown zone with a throttle opening of about 87% or more and the extremely low pre-lunch zone with a throttle opening of about 10% or less are set based on the turbine rotation speed required in that zone from the viewpoint of engine operability. .

Therefore, the turbine rotational speed after the shift does not change from the downshift zone to the upshift zone or from the shift amplifier zone to the downshift zone, and the shift can be performed without hunting caused by repeated amplifier shifts and downshifts. The downshift line is also used as a lock-up OFF control line 11 for performing lock-up ON/OFF control.

The calculation results of the CPU 203 are transmitted via the input/output device 201 and the drive circuit 211 to the 1-2 shift valve 110, the 2-3 shift valve 12, which is the speed change control valve described with reference to FIG.
It is given as a signal to control the excitation of the solenoid valve group 211 that operates the 0.3-4 shift valve 130 and the lock-up control valve 133. This solenoid valve group 211 includes 1
-2 shift I valve 110.2-3 shift valve 120.3-4
The solenoid valves SLI, SL2, SL3, and SL4 of the shift valve 130 and the lock-up control valve 133 are included.

An example of control of an automatic transmission by the electronic control circuit 200 will be described below. The electronic control circuit 200 is preferably configured by a microcomputer, and a program installed in the electronic control circuit 200 is executed, for example, according to the flowcharts shown in FIG. 6 and subsequent figures.

FIG. 6 shows an overall flowchart of the shift control, and as can be seen from this figure, the shift control is first performed from initialization settings. In this initialization setting, first, the ports of each control valve that switches the hydraulic control circuit of the automatic transmission and necessary counters are initialized, and the gear transmission mechanism 20 is set to series, and the lock-up clutch 15 is set to release. Thereafter, various working areas of the electronic control circuit 200 are initialized to complete the initialization settings.

After this initialization setting, a step of reading the position of the select valve 103, that is, the shift range is performed. Next, it is determined whether the read shift range is the D range. When this determination is No, it is determined whether the shift range is 2 ranges or not. When this determination is YES, that is, when the shift range is 2nd range, a signal is generated to control the shift valve so as to release the lockup and fix the gear transmission mechanism 20 at the 2nd speed. On the other hand, the judgment of the above two ranges is No.
In this case, since the shift range is the L range, first the lockup is released, and then it is calculated whether or not the engine will overrun when downshifting to the first gear.

Thereafter, based on this calculation, it is determined whether or not an overrun will occur, and if this determination is NO, the gear is shifted to the first gear, and if this determination is YES, the gear is shifted to the second gear.

On the other hand, if the determination as to whether the vehicle is in the D range is YES, a shift and lockup map including a shift change control line and a lockup control line is set.

Next, shift-up speed change control including a shift-up determination is performed. This shift-up speed change control is executed according to the shift-up speed change control subroutine shown in FIG.

Shift-up speed change control This shift-up speed change control involves first reading the gear position, that is, the position of the gear transmission mechanism 20, and then determining whether or not the current speed is 4 based on the read gear position. You can start from This judgment is YES
In this case, no further upshift can be performed, so flags 1 and 2 are reset, that is, set to O, and the control is terminated. This flag 1 and flag 2
is set at the door where a one-step upshift and a skip shift-up are executed, respectively, to store the upshift state.

6. On the other hand, when the above determination is No, the current throttle opening degree is read out, and a shift-up map corresponding to the read throttle opening degree is read out. An example of this shift-up map is shown in FIG.

Next, read out the actual turbine rotation speed (TSP), and compare this turbine rotation speed with the shift line indicated by M fu in FIG. 8, for example, on the shift up map read out above,
It is determined whether the turbine rotation speed is larger than the set turbine rotation speed indicated by the shift line Mfu in relation to the throttle opening.

When the actual turbine rotational speed is larger than the set turbine rotational speed in relation to the throttle opening, a skip shift up map corresponding to the current throttle opening is read out. This skip-shift-up map is a map used when attempting to skip one gear stage and shift up from, for example, second gear to fourth gear all at once.

Next, the actual turbine rotation speed (ESI) is compared with the shift line indicated by Msu in FIG. 8 of the above skip shift up map, and this actual turbine rotation speed (TSP) is
It is determined whether or not is larger than the set turbine rotation speed indicated by this shift line Msu in relation to the throttle opening. When this determination is No, flag 1 for normal one-stage upshifting is read out. Next, it is determined whether the read flag l is 0 or l, that is, whether it is in the Re s e state or the Set state. Flag 1 is changed from 0 to 1 when a 1st gear upshift is executed, and the flag l that stores the 1st gear upshift state is Re.
When s e is in state, release the lockup,
Next, shift up one gear and set flag 1 to Sera I.
Complete the gear upshift control.

On the other hand, when the determination as to whether or not the actual turbine rotation speed '1' sp is larger than the set turbine rotation speed indicated in the shift line Msu of the skip shift up map is YES,
Read flag 2 for skip shift up. This flag 2 is for storing the skip-up state, and is changed from 0 to 1 by a skip shift-up operation. Next, check whether the read flag 2 is 0 or 1, that is, Re5.
It is determined whether it is in the et state or the set state. When this determination is YES, that is, in the Re5et state, the lockup is released and it is determined whether or not the gear is currently in the third gear. If this judgment is No, it is possible to shift up by 2 steps, so shift up by 2 steps. If this judgment is YES or S, it is not possible to shift up by 2 steps, so shift up by 1 step. With this, the skip shift up control is completed.

When the determination as to whether the flag 2 is 0 in the skip shift up control is No, that is, when it is in the Set state, the control is stopped there. When Ycs, flag 1 is read, and when flag 1 is 0, the judgment is NO, that is, S
When in the ET state, the system shifts to the 1st gear upshift control system,
After canceling t' knock-up, a one-step upshift is performed.

In this case, since the flag l is already set, there is no need to set it again.

When the determination as to whether flag l in the first-stage shift up control system is 0 or l is No, the shift line M su of the skip shift up map is multiplied by 0.8 to create a new shift line M indicated by a broken line. form s u '.

Next, the current actual turbine rotation speed T s p is read out, and it is determined whether or not this actual turbine rotation speed T sp is larger than the set turbine rotation speed marked on the shift line M s u ′ in relation to the throttle opening. Determine. If the result of this determination is No, it indicates that a one-stage shift 1-up is being performed or a skip shift-up is not being performed, and therefore flag 2 is reset after this.
On the other hand, if the result of this determination is YES, the control is completed as is.

If the actual turbine rotation speed 'f' sp is larger than the set turbine rotation speed indicated by the shift line M f u in relation to the throttle opening degree, if the judgment is NO, the shift line M f u is set by 0.8. , to form a new shift line M s u ′ shown by a broken line. Next, it is determined whether the current turbine rotation speed 'Fs p is larger than the set turbine rotation speed indicated by the speed change number M s u '. When this determination is No, flag 1.2 is reset to prepare for the next cycle, and when this determination is YES, the control is immediately terminated and thereafter shifts to downshift control.

The downshift control is executed according to the downshift control subroutine shown in FIG. This downshift control is performed by first reading out the gear position, as in the case of upshift control.

Next, based on the read gear position, it is determined whether or not the vehicle is currently in the first gear. If it is not the first speed, the current throttle opening is read out, and then the turbine rotational speed is read out from the shift down map using the read throttle opening as an address. An example of this shift down map is shown in FIG. Next, the actual turbine rotation speed T
sp is read out, and this turbine rotational speed is stored in the downshift map, for example, on the downshift shift line indicated by Mfd in FIG. 10 [data of the downshift point set by the downshift shift line Ld in FIG. For example, the turbine rotation speed 'r s
It is determined whether p is smaller than the set turbine rotation speed indicated by the downshift shift line Mfd in relation to the throttle opening.

When the actual turbine rotation speed is smaller than the set turbine rotation speed, a skip shift down map corresponding to the current throttle opening is read out.

Next, the actual turbine rotational speed 'r S l) is plotted, for example, in FIG. 10 of the above-mentioned skip shift down map.
With reference to the skip down shift line Mfd, it is determined whether the turbine rotation speed "sp" is smaller than the set turbine rotation speed indicated by the down shift line Mfd in relation to the throttle opening.

When the actual turbine rotation speed is smaller than the set turbine rotation speed, a skip shift down map corresponding to the current throttle opening is read out.

Next, compare the actual turbine rotation speed 'I'' sp with the skip down shift line indicated by Msd in FIG. It is determined whether or not the turbine rotation speed is smaller than the set turbine rotation speed indicated by Msd. When this determination is No, flag D for skip shift down
is reset, and the flag C for a normal one-stage downshift is read. Flag C is changed from 0 to 1 when downshifting by one gear, and flag D is changed from O to 1 when downshifting is performed.

Next, it is determined whether this flag C is 0 or 1 and whether it is in the Re5et state or the Set state. When the flag C is in the Re se state, the lock-up is released, a one-speed downshift is performed, and then the flag C is set to complete the first-speed shift (downshift control).

On the other hand, if the determination as to whether or not the actual turbine rotation speed 71'SI) is smaller than the set turbine rotation speed indicated by the shift line Msd is YES, the flag D is read out, and whether this flag D is 0 or 1 is determined. , Zunawaji determines whether to reset or set. When flag D is 0, flag C is read and it is determined whether flag C is 0 or not. When both flag D1 and flag C are 0, that is, when the Re s e state is set, flags C and D are set, and then the current 2
Determine if it is fast. If it is not in 2nd gear, a 2-speed downshift is possible, so perform a 2-speed downshift,
Since skip downshifting is not possible, the system moves to the 1st gear downshift control system to release the lockup and downshift by 1st gear. Flag C in this control system
Even when the determination as to whether is 0 is NO, the system shifts to the 1st gear downshift control system and performs the same shift.

When the above-mentioned determination of 1st speed is YES, downshifting is impossible, so flags C and D are reset and the control is completed.

In addition, when the actual turbine rotation speed Tsp is not smaller than the set turbine rotation speed indicated by the first-stage downshift shift line Mfd, read out the downshift map according to the current mode and throttle opening, and change the speed of this map. The set turbine rotation speed shown on the line Mfd is multiplied by 0.8 to form a new shift line Mfd'. Next, when the current actual turbine rotation speed T s p is smaller than the above-mentioned shift line Mfd', the control is completed as it is, whereas when it is not smaller, the flags C and D are reset and the control is completed,
After this, the system shifts to lock-up control.

In addition, in the shift-up speed change control and shift-down speed change control explained above, when a speed change is not performed,
The reason why hysteresis is created by multiplying the map's shift line by 0.8 to form a new shift line is to prevent chuck ring from occurring due to frequent gear changes when the turbine speed is at the critical speed. This is to prevent

Upshift and downshift control according to the control device according to the present invention has been described above, and now lockup control will be briefly described.

Lock-up controlIn terms of lock-up control, lock-up control is based on the relationship between the current turbine rotational speed 'r ps and the current throttle opening to the lock-up control line Le and lock-up OFF control line Le shown in FIG. 5A. ′, the determination is made based on whether or not this turbine rotational speed is larger than the set turbine rotational speed indicated by the control lines Le and Le′.

In principle, if this judgment is NO, lock-up O
FF control is performed, and when YES, lock up N
O control is performed. Note that the control lines Le, Le'
The purpose of setting is to add hysteresis to the lock amplifier judgment and prevent hunting. however,
For example, if the current gear position is the first gear, if the warm-up state of the engine is too low to be suitable for lock-up, or if the engine is already in the lock-up state, lock-up control is not performed.

[Brief explanation of the drawing]

Figure 1 is a graph showing the turbine rotation speed vs. generated output characteristics when the fuel flow rate is constant at each value, and Figure 2 is a graph showing the turbine rotation speed vs. throttle opening when the fuel flow rate is constant at each value. FIG. 3 is a graph showing the characteristics of an automatic transmission control device according to an embodiment of the present invention; FIG. FIG. 5 is a schematic diagram showing the electronic control circuit of the automatic transmission; FIG. 5A is a diagram showing a shift-up shift line, a shift-down shift line, and lock-up ON-OFF control. 6, 7 and 9 are flowcharts of advance control according to the present invention, and FIGS. 8 and 10 are shift up maps and shift down maps, respectively. a... Torque converter, b... Speed change gear mechanism, C
...Speed changeover means, e...Electromagnetic means, f...Turbine rotation speed sensor, g...Engine load sensor, h.
...Storage means, i...Shift down determination means, j...
・Shift-up determining means, k... Drive means, 10...
・Torque converter, 11...Pump, 12...Turbine, 100...Hydraulic pump, 103...Select valve, 200...Electronic control circuit, 207...Load sensor, 209...Turbine Rotation speed sensor. Patent applicant: Toyo Kogyo Co., Ltd. - Figure 5A No Oton I! ]'Fj, wr, l), m X
1000Figure 3Figure 6

Claims (1)

[Claims] a torque converter connected to the output shaft of the engine; a speed change gear mechanism connected to the output shaft of the torque converter;
A speed change switching means for switching the power transmission path of the speed change gear mechanism to perform a speed change operation, and an electromagnetic means for controlling the supply of pressure fluid to a fluid type actuator that operates the speed change switching means, the electromagnetic means being driven and controlled to perform a speed change operation. In automatic transmissions that perform The engine load sensor that detects the load is calculated based on the difference in gear ratio between adjacent gears in each of the multiple lines showing the turbine rotation speed vs. generated output characteristics when the fuel consumption rate is constant at each stage. Find the equal output point on the low revolution side and the equal output point on the high revolution side that are equal to each other by i + the rotation speed fluctuation range of the output shaft of the torque converter, and find the equal output point on the low revolution side in each of the above lines. A shift-down shift line set based on the low-rev overturning output curve formed by connecting each line, and a shift-up shift set based on the high-speed output curve formed by connecting the high-speed output points on each line. a storage means storing the line and the output signal of the turbine rotation speed sensor and the output signal of the engine load sensor, and compares these output signals with the downshift shift line to determine whether or not a downshift is required. a shift-down determining means for determining and issuing a shift-down command signal when necessary; receiving the output signal of the engine rotation speed sensor and the output signal of the engine load sensor; and comparing these output signals with the shift amplifier shift line. a shift-up determination means for determining whether or not an up-shift is required and issuing a shift-up command signal if necessary; a shift-down command signal of the shift-down determination means; and a shift-up command signal of the shift-up determination means. receive,
A control device for an automatic transmission comprising a drive means that automatically changes gears by driving and controlling the electromagnetic means based on these two command signals.