JPS59222650A - Control device in automatic transmission - Google Patents

Abstract

PURPOSE:To enhance fuel consumption, by carrying out the control of shift-down with the use of a speed changing curve which is set in accordance with a turbine rotational speed v.s. engine load characteristic as a shift-down speed changing curve, with which the torque ratio of input and output shafts of a torque converter becomes one. CONSTITUTION:Whether shift-down is necessary or not is determined by comparing output signals from a turbine rotational speed sensor (b) for detecting the output shaft rotational speed of a torque converter (a) and an engine load sensor (g) for detecting engine load, with a shift-down speed changing curve which is set and stored in accordance with a turbine rotational speed and an engine load that allow the torque ratio of input and output shafts of the torque converter (a) to become substantial one. When shifting-down is necessary, a shift-down discriminating means (h) delivers a shift-down instruction signal to operate a drive means (j).

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.

BACKGROUND OF THE INVENTION Automatic transmissions commonly used today are constructed by combining a torque converter and a multi-gear type transmission mechanism having a gear mechanism such as a planetary gear mechanism. A hydraulic mechanism is usually used for speed change control of such automatic transmissions, and the hydraulic circuit is switched using a mechanical or electromagnetic switching valve, thereby controlling frictional elements such as brakes and clutches associated with the multi-gear type transmission mechanism. It operates as appropriate to switch the engine power transmission system and 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 this device
The electromagnetic switching valve is selectively activated by the signal,
Normally, this changes the hydraulic circuit to change gears.

In the conventional device, the shift line was determined using the vehicle speed-engine load characteristic as a control parameter, but since the vehicle speed is a control parameter via the transmission,
A different pattern of shift line is required for each gear stage, which makes control complicated. In addition, since the engine load is detected by detecting the erosotor 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 rotation 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, shift down shift line, and lockup cant line is small, and there is no restriction line such as a stall line, so there is greater freedom when setting the shift line. It has the advantage of being large.

OBJECTS OF THE INVENTION The present invention provides a control system for an automatic transmission of the type that uses the turbine speed-engine load characteristic as a control parameter, which can set a gear stage so that the torque converter can always operate in a high efficiency range. It is an object of the present invention to provide a control device for an automatic transmission that can improve the 3I'A cost.

Development of the Invention and Structure of the Invention Figure 1 shows the performance of the torque converter, with the horizontal axis representing the speed ratio between the engine speed and the turbine speed, and the edge axis representing the torque ratio of the input/output shaft of the torque converter. It is a graph. As can be seen from FIG. 1, the torque ratio has a characteristic that it decreases as the -recording speed ratio increases.

In other words, the torque converter has an automatic speed change function in which the torque increases greatly when the turbine rotation speed is slower than the pump rotation speed, and the torque increase decreases as the Kubin rotation speed approaches the pump rotation speed. However, for example, in a torque converter having the performance shown in FIG. 1, when the speed ratio becomes 0.8 or more, the 1-luke ratio becomes 1 or less, resulting in a loss of 1i of torque. Therefore, as shown in FIG. 2, the present invention determines a turbine rotation speed-throttle opening characteristic curve that provides a predetermined speed ratio where the l/lux ratio is 1, and based on this characteristic curve. It is designed to perform speed change control.

That is, as shown in FIG. 3, the present invention includes a torque converter a connected to the output shaft of the engine, and a speed change gear mechanism b connected to the output shaft of the torque converter a.
, an electromagnetic means e for controlling the supply of pressure fluid to a fluid type actuator that operates the speed change switching means; In an automatic transmission that performs speed change operation under drive control, 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, an output signal of the turbine rotation speed sensor f, and Receives the output signals of the engine load sensor g and converts these output signals into a downshift shift line set and stored based on the turbine rotation speed and engine load at which the torque ratio of the input and output shafts of the torque converter a becomes substantially 1. Shift down 6 compared to
a downshift determining means h that determines whether or not a downshift is required and issues a downshift command signal if necessary;
Upon receiving the output signal of the turbine rotation speed sensor f and the output signal of the engine load sensor g, these output signals are converted into a torque converter a calculated according to the difference in gear ratio between adjacent gear shift sections. Determine whether or not a shift amplifier is required by comparing it with a shift amplifier shift line set at a higher rotation side than the shift 1-down shift line in accordance with at least the rotational speed shift width of the output shaft, and if necessary. a shift amplifier determining means i which issues a shift amplifier command signal to the shift amplifier determining means; and a shift down command to the shift down determining means (receiving the shift up command signal from No. 4 and the shift amplifier determining means i, and based on these two command signals); a drive means j that automatically changes speed by controlling the drive of the electromagnetic means e;
It is characterized by having the following.

In the automatic transmission control device of the present invention having a configuration that exceeds the effects of the invention, the downshift shift line is based on the turbine rotation speed-engine load characteristic such that the torque ratio of the input and output shafts of the torque converter becomes substantially 1. Since downshift control is performed using a set shift line, the vehicle can always be operated with a torque ratio of 1 or more, resulting in good operating efficiency and improved fuel efficiency.

In addition, in the operating range where the torque ratio is 1 or more, the turbine rotational speed approaches the pump rotational speed, so lock-up control can be performed to directly connect the pump and turbine. It is possible to improve fuel efficiency.

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 attached documents.

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 10, a multi-stage gear transmission mechanism 20, and an overdrive planetary gear transmission mechanism 5o disposed between the torque converter 1o and the multi-stage gear transmission mechanism 20. has been done.

The torque converter 10 includes a pump 11 coupled to an engine output shaft I, a turbine 12 disposed opposite the pump 11, and a stator 13 disposed between the pump 11 and the turbine 12. A converter output shaft 14 is coupled to the converter output shaft 14 . Converter output shaft 14
A lock amplifier clutch 15 is provided between the pump li and the pump li. This lock-up clutch 15 is constantly pushed in the engagement direction by hydraulic oil pressure circulating within the torque converter 10, and is held in an open state by a releasing hydraulic pressure supplied to the clutch 15 from the outside.

The multi-stage gear transmission mechanism 20 has a front-stage planetary gear mechanism 21 and a rear-stage planetary gear mechanism 22 7 , and the sun gear 23 of the front-stage planetary gear mechanism 21 and the sun gear 24 of the rear-stage & star gear mechanism 22 are connected by a connecting shaft 25 . has been done. Multi-stage gear transmission mechanism 2
0 input shaft 26 is connected to the connecting shaft 2 via the front clutch 27.
5 and an internal gear 29 of the front planetary gear mechanism 21 via a rear cuff lunch 28. Connection shaft 25 or sun gear 23.24
A front brake 30 is provided between the front brake and the transmission case. Planetary carrier 3 of front stage i star gear mechanism 21
1 and the internal gear 3 of the rear planetary gear mechanism 22
3 is connected to an output shaft 34, and a rear brake 36 and a one-way clutch 37 are provided between the planetary carrier 35 of the rear planetary pawl mechanism 22 and the transmission case.

The overdrive planetary float transmission mechanism 50 includes a planetary carrier 5 that rotatably supports a planetary gear 5.
2 is connected to the output shaft 14 of the torque converter 10, 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 input 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 can obtain the required speed by appropriately operating the clutch 27, 28 and brake 30, 31. I can do it.

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 coupled in a direct connection, the brake 56 is engaged and the clutch 54 is released, coupling the shafts 14 and 26 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 this oil pump 100 into a pressure line 101 is adjusted by a pressure regulating valve 102 and sent to a select valve 103. be guided. Select valve 103, 1
．． 2, D, N, , R, )), and when the select valve is in the 1.2 and P positions, the pressure line 1
01 communicates with boats a, b, and c of valve 103.

Boat a has an actuator 1 for operating the rear clutch 28.
04, and when the valve 103 is in the above position, the rear clutch 28 is held engaged. ball
-a is also connected near the left power end of the 1-2 shift valve 110, pushing the spool to the right in FIG. Boat a further passes 1-2 via the first line Li.
A third line L is connected to the right end of the shift valve 110 through the second line L2 to the right end of the 2-3 shift I-valve 120.
3 to the upper end of the 3-4 shift valve 130, respectively. The above first, second and third lines LI
First, second and third drain lines D1, D2 and D3 are branched from L2 and L3, respectively.
Connected to these drain lines DI, 1) 2, and D3 are first, second, and third solenoid valves SLI, SL2, and SL3 that open and close the drain lines Di D2 and D3. "- Solenoid valve SLI, SL2, SL
3, when energized with the fin 101 and ball l-a communicating, each drain line DI, D2, D3 is closed, and as a result, the pressure nozzles in the first, second, and third lines are closed. It is designed to increase the

Boat b is also connected to second lock valve 105 via line 140, and this pressure acts to push the spool of valve 105 downward in the figure. When the spool of valve 105 is in the downward position: 1. Lines 140 and 141 communicate with each other, and hydraulic pressure is introduced into the locking side pressure chamber of the actuator 108 of the front brake 30.
0 in the direction of the actuating force. The ball lc is connected to a second u-socket 105, and this pressure acts to push the spool of the valve 105 upward. Additionally, boat C is connected to a 2-3 shift valve 120 via pressure line 106.
It is connected to the. This line 106 is activated when the solenoid valve SL2 of the second drain line D2 is energized, the pressure within the second line L2 is increased, and this pressure moves the spool of the 2-3 shift valve 120 to the left. , connected to line 107. The line 107 is connected to the release side pressure chamber of the actuator 108 of the front brake, and when hydraulic pressure is introduced into the pressure chamber, the actuator 108 operates the brake 30 in the release direction against the pressure in 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 has a boat d that communicates with the pressure line 101 in the ■ position, and this boat d reaches the l-2 shift valve 110 via a line 112 and is further connected to the actuator 114 of the rear brake 36 via a line 113. Ru.

■-2 shift valve 110 and 2-3 shift valve 120 are operated by solenoid valves SLI and SLl in response to a predetermined signal.
When 2 is energized, the spool is moved to switch the line, thereby operating a predetermined brake or clutch, thereby performing the gear shifting operations of 12.2-3, respectively. The hydraulic control circuit also includes a cantback valve 115 that stabilizes the hydraulic pressure from the regulator 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 Throttle valve 11
A throttle backup valve 117 is provided to assist the engine. Furthermore, the hydraulic control circuit of this example is provided with a 3-4 shift valve 130 and an actuator 132 in order to control the planetary gear shift m, 50 for overdrive, the clamper 54, and the brake 56. The engagement 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 engagement direction. This 3-4 shift valve is similar to J-Note 1-2.2-3 shift valve 110.120, and when the trenoid valve SL3 is excited, the spool 1 of the valve
31 moves downward, pressure line lO1 and line 122
is shut off and line 122 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 engagement direction, and the actuator 1 of the clutch 54 is activated.
34 acts to release the clutch 54.

Furthermore, the hydraulic control circuit of this example includes a lock-up control valve 13.
3 is provided, and this lock-up control valve 133 is communicated with the port].a of the select valve 1()3 via line L4. A drain line D4, which is provided with a solenoid valve S L 4, branches off from this line L4, similar to the drain lines D1, D2, and D3. The lock-up control valve 133 is activated when the solenoid valve SL4 is energized.
When drain line LJ4 is closed and the pressure in line L4 increases, its spool is connected to line 123 and line 1.
24 is cut off and the line 124 is further drained, thereby moving the lock amplifier clutch 15 in the connecting direction.

In the above configuration, each gear stage and opening, the operational relationship between the pull-up and each solenoid, and each gear stage and clutch,
The operating relationship of the brakes is shown in the following table G2F-4-0 No. 1
Table 2 Electronic control rules using microcomputer Next, referring to FIG. 5, an electronic control circuit 2oO 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 2o2 (hereinafter referred to as RAM) and a central processing unit 2o3 (hereinafter referred to as CI U). The input/output device 201 includes an engine 204
Intake tract I? Reta throttle valve 2 installed in 11205
The engine's negative iI is detected from the opening degree of 06, and the negative (WJ
A load sensor 207 that outputs a signal SL, a turbine rotation speed sensor 2 ( ) 9 that detects the rotation speed of the converter output shaft 14 and outputs a turbine rotation speed signal sT, and other sensors that detect running conditions are connected. The above-mentioned signals, etc., are manually generated from these sensors.

The input/output device 201 receives a load signal S from the sensor.
L, processes the turbine rotational speed signal s'F, and stores it in RAM 2.
02 d supply. The RAM 20'2 stores these signals SL.
and S'r, and supplies these signal sequences 5LXST or other data to CPU 2 O 3 in response to instructions from CPU 203. CPU20
3. According to a program adapted to the speed change control of the present invention, the turbine rotation speed signal ST is read out according to the above-mentioned negative front signal SL, for example, according to the Tahin rotation speed-engine load characteristic as shown in FIG. 5A. Based on the determined upshift line LU and shift I/down shift line Ld, a calculation is made as to whether or not a shift should be made. The downshift line Ld is determined based on the line L in FIG. 2 where the torque ratio of the input and output shafts of the torque converter 0 is 1, as described above.

That is, in zones other than the kickdown zone where the throttle opening is, for example, 88% or more and the extremely low load zone where the throttle opening is, for example, 10% or more, the downshift shift line Ld is made to coincide with the line L. . In addition, the shift-up speed change line Lu is the rotational speed fluctuation range H (H-"l"nd・-8 =
However, 'rnd: Turbine rotation speed at downshift point,
G: Gear ratio, A: Difference in gear ratio between adjacent gear ratios] 1) is set on the higher rotation side than the downshift line. Therefore, the turbine rotation speed after the shift changes from the shift l-down zone to the shift up zone,
Alternatively, the shift 1 downshift is not entered from the shift door knob zone, and the shift can be executed without causing a knob shift or downshift. Note that the shift 1 down shift line is also used as a lock-up OFF control line L e I for performing lock-up ON/OFF control.

CPU 2 (+3 calculation result is input/output device 20
1 and the drive circuit 211 to operate the 1-2 shift valve 110, the 2-3 shift valve 120, the 3-4 shift valve 130, and the lock-up control valve 133, which are the shift control valves described with reference to FIG. It is given as a signal to control the excitation of the solenoid valve group 211. This solenoid valve group 21
1 has ■-2 shift valve 110.2-
: 3 shift valves 120, 3-4 shift valves 130, lock-up control valves 133 solenoid valves SLI, SL2, S
Includes L3 and SL4.

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 the overall flowchart 1 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 initialize the ports and necessary counters of each control valve that switches the hydraulic control circuit of the automatic transmission, and then sequentially shift the gear shift mechanism 20 to the lock-up clutch 1.
Set 5 to release. After this, electronic control circuit 2
Initialize the various working areas of 00 to complete the initialization settings.

After this initialization setting, the shift knob is operated to read the shift range of the select valve 103. Next, it is determined whether the read shift range is the D range. When this determination is NO, it is determined whether or not the shift I range is the 2nd range. When this determination is YES, that is, when the shift range is the 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 second speed. On the other hand, if the above 2nd range determination is No, the shift range is lunge, so first release the lock knob, then downshift to 1st gear, and check whether the engine will overrun or not. calculate. Thereafter, based on this calculation, it is determined whether or not an overrun will occur, and if the determination is No, the gear is shifted to the first gear, and if the determination is YE or S, 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 routine shown in FIG.

Shift-up speed change control This shift-up speed change control first reads the gear position, that is, the position of the gear transmission mechanism 20, and based on the read gear position, it is determined whether or not the current gear is in the fourth gear. You can start. This judgment is YES
In this case, since no further upshift can be performed, flags 1 and 2 are reset, that is, set to 0, and the control is terminated. Flag I and flag 2 are for one-step upshift and skip shift, respectively!
This is set when an upshift is executed, and is used to store the upshift state.

On the other hand, if the above judgment is NO, the current throttle opening degree is read out, and the Kuhin rotation speed is read out from the shift-up map using the read throttle opening degree as an address. An example of this shift-up map is shown in FIG.

Next, the actual turbine rotation speed (TSP) is read out, and this turbine rotation speed is calculated based on the shift-up map, for example, the shift line indicated by Mfu in FIG. Based on the data stored at the points (for example, throttle opening θ is set to address and the corresponding turbine rotational speed N is memorized), the speed change line is determined based on the relationship between the turbine rotational speed and the throttle opening. M
It is determined whether or not the turbine rotation speed is greater than the set turbine rotation speed indicated by fu.

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, set the actual turbine rotation speed (ESI) to, for example, 9
No. 8 of the above skip shift up map
In light of the shift line M 3 u in the diagram, determine whether the actual turbine rotation speed T s p is larger than the set turbine rotation speed indicated by the shift line M s u in relation to the throttle opening. Determine whether This judgment is NO
At this time, flag 1 for normal one-stage upshifting is read. Next, whether this read flag l is 0 or 1,
That is, it is determined whether it is in the Ra5eL state or the Set state. Flag 1 is changed from O to 1 when a 1st gear upshift is executed. When flag 1, which stores the 1st gear upshift state, is in the Re5et state, the lockup is released and then the 1st gear upshift is performed. Then, set flag 1 to CERA I to complete the 1st gear shift] and up-shift control.

On the other hand, when the determination as to whether the actual turbine rotation speed Tsp is greater than the set turbine rotation speed indicated by the shift line Msu of the skip shift up map is YES, flag 2 for skip shift up is read out. 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 O or 1, that is, Re Se
3. Determine whether p is in the state or not.

When this determination is YES, that is, Re s e
When in the state, lock-up is released and it is determined whether or not the gear is currently in third gear. If this determination is NO, it is possible to shift up two gears, so a two gear upshift is performed, and if this determination is YES, it is not possible to shift up two gears, so shift up the first gear. Then, the skip shift 1-up control is completed.

When the determination as to whether flag 2 is 0 in the skip shift up control is NO, that is, when the state is set, the control is stopped there. When Yes, flag l is read, and when the determination whether flag l is () is NO, that is, when it is in the Set state, shift by 1 step)・up-based fill
Move to the + system, release the lockup, and then shift up one step.

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

Flag 1 in the above 1st stage shift I/up control system is 0
If the answer is NO, multiply the shift line MSIJ on the skip shift up map by 0.8.

A new shift line Msu' shown by a broken line is formed.

Next, the current actual turbine rotation speed 'r 3 I) is read out, and it is determined whether this actual turbine rotation speed Tsp is larger than the set turbine rotation speed indicated by this shift line MS'tJ' in relation to the throttle opening degree. Determine whether or not.

If the result of this determination is NO, it indicates that either a one-stage upshift is being performed or a skip upshifting is not being performed, and therefore flag 2 is reset after this.
-Force If the result of this determination is YES, the control is completed as is.

If the determination as to whether the actual turbine rotation speed 'l''sp is larger than the set turbine rotation speed indicated by the shift line Mfu in relation to the throttle opening is NO, the shift line Mfu is multiplied by 0.8. Then, a new shift line M s u ′ indicated by a broken line is formed.Next, it is determined whether the current turbine rotation speed Ts p is larger than the set turbine rotation speed indicated by the above-mentioned shift number Msu ′. Judgment is N
When the determination is 0, the flags 1 and 2 are reset to prepare for the 0th cycle, and when the determination is YES, the control is immediately terminated, and thereafter the shift-down speed change control is performed.

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 not read out from the shift down map using the read throttle opening as an address. An example of this downshift map is shown in FIG. Next, read out the actual turbine rotation speed 'rsp, and use this turbine rotation speed as an example of the downshift map, which is the downshift shift line indicated by Mfd in FIG. The shift down point data set by Ld is stored (for example, the throttle opening θ address is stored and the corresponding turbine rotation speed N is stored)], and the turbine rotation speed Tsp is shifted down in relation to the throttle opening. It is determined whether the rotation speed of the turbine is smaller than the set turbine rotation speed indicated by the shift line Mfd.

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 rotation speed Tsp is determined by comparing the actual turbine rotation speed Tsp with the skip down shift line indicated by Msd in FIG.
It is determined whether sp 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, input the actual turbine speed "I'sp" to fJ4101J in the skip shift down map above
With reference to the skip down shift line indicated by d, it is determined whether the actual turbine rotation speed Tsp is smaller than the set turbine rotation speed indicated by the shift line Msd. When this determination is No, the flag D for skip downshifting is reset, and the flag C for normal one-stage downshifting is read out. The flag C is changed from O to 1 when the gear is shifted down by one gear, and the flag D is changed from 0 to I when the gear is skip shifted down.

Next, it is determined whether this flag C is 0 or 1, that is, whether it is in the Re5et state or the 3et state. When the flag C is in the Res a L state, the lockup is released and a 1.1-speed downshift is performed, and then the flag C is set to complete the 1st-speed downshift control.

On the other hand, if the determination as to whether or not the actual turbine rotation speed 1"sp is smaller than the set turbine rotation speed set by 4 in the shift line Msd is YES, the flag D is read out, and the flag D is read out.
It is determined whether is O or I, that is, whether it is a reset or a cell. When flag D is 0, flag C is read and it is determined whether flag C is 0 or not. When flag D1 and flag C are both 0, that is, when the state is Re s e , flags C and D are set, and then it is determined whether the current speed is 2nd. If it is not 2nd gear, a 2nd gear downshift is possible, so a 2nd gear downshift is performed, and since a skip downshift is not possible, the system moves to the 1st gear downshift control system, releases the lockup, and shifts to the 1st gear. Do the down. Even when the determination as to whether the flag C is 0 in this lj control system is NO, the shift is shifted to the 1st-stage downshift control system and a similar speed change is performed.

If the above determination of 1st speed is YES, downshifting is not possible, so the flag [;, 1] is reset and the control is completed.

Also, if the actual turbine rotation speed 'T' Sp is not smaller than the set turbine rotation speed indicated by the first-stage downshift shift line Mfd, the shift down map corresponding to the current mote and throttle opening is displayed. 0.8 to the set turbine rotation speed shown on the shift line Mfd of this map.
A new shift line Mfd' is formed by multiplying by Mfd'. Next, when the current actual turbine rotation speed "I' S I) is smaller than the above-mentioned shift line Mfd', the control is completed as it is,
On the other hand, if it is not smaller, flags C and D are reset, control is completed, and then lock-up control is entered.

In addition, in the shift)' knob shift control and downshift shift control explained above, when a shift is not performed, the shift line of the map is multiplied by 0.13 to form a new shift line to create hysteresis. This is to prevent chuck ring from occurring due to frequent gear changes when the turbine rotational speed is at the critical speed change.

Hereinafter, the shift-up and shift-down shift control according to the control device according to the embodiment of the present invention has been explained.
Next, locking element one-tube control will be explained inside the cylinder.

Lock-up control This lock-up control is basically based on the relationship between the current turbine rotation speed 1'' I) S and the current throttle opening, and the lock-up control line Le and the OFF control line Le' shown in FIG. 5A. This determination is made based on a determination as to whether or not this turbine rotational speed is greater than the set turbine rotational speed indicated by the control lines L e - and L e '. In principle, if this determination is No, lock-up OFF control is performed, and if YES, lock-up No control is performed. The control line Le%Le'' is set in order to add hysteresis to the lock amplifier determination and prevent hunting.

However, for example, if the current gear position is 1st gear, if the warm-up state of the engine is so low that it does not turn white (in the second gear), or even if the engine is already in the first gear position, the lock-up Control control is not performed.

[Brief explanation of drawings]

Figure 1 explains the performance of a torque converter. The graph in Figure 2 shows the turbine rotational speed at which the torque converter reaches a predetermined gear ratio where the torque ratio of the input and output shafts becomes 1.
A graph showing the throttle opening characteristic, FIG. 3, does not show the structure 1 of the control device for an automatic transmission of the present invention, and FIG. Fig. 5 is a schematic diagram showing the electrical control circuit of the automatic transmission, Fig. 5 is a schematic diagram showing the electrical control circuit of the automatic transmission. Figures 6121, 7, 1 and 9 are diagrams showing a shift line, a shift-down shift line, and a lock-up ON/OFF control line, and Figs. are a shift up map and a shift down map, respectively. a...torque converter, b...speed change float mechanism, (
2...speed change switching means, d...hydraulic actuator, e...electromagnetic means, f...turbine rotation speed sensor,
g... Engine load sensor, 11... Shift down discrimination means, i... Shift up discrimination means, j... Drive means, 10... Torque converter, 11... Pump, 12
...Turbine, 100...Ura)-1 pump, 103
...Select 1-valve, 200...Electric J'' control circuit, 2
07...Load sensor, 21) R...Turbine rotation speed sensor. Patent Applicant: Toyo, 2nd Industry Stock Company, F Ironokaya and Otsu Coupling Rotation Speeds R, P, M. Figure 5A Figure 3 Figure 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;
It is equipped with a speed change switching means for changing and freezing the power transmission path of the speed change gear mechanism, and an electromagnetic means for controlling the supply of pressure fluid to a fluid type actuator that operates the speed change switching means, and the electromagnetic means is drive-controlled. In an automatic transmission that performs a speed change operation, a turbine rotation speed sensor detects the output shaft rotation speed of a torque converter, an engine load sensor detects the engine load, an output signal of the turbine rotation speed sensor and an engine load sensor. In response to the output tti of the torque converter, these output signals are converted into a shift 1-down shift line that is set and stored based on the turbine rotation speed and engine load at which the torque ratio of the input and output shafts of the torque converter becomes substantially 1. a downshift determination means for determining whether a downshift is required or not and issuing a downshift command signal if necessary; receiving the output signal of the engine rotation speed sensor and the output signal of the engine load sensor; The output signal of the shift amplifier is set to a higher rotation side than the shift amplifier shift line in response to the rotational speed fluctuation range of the output shaft of the torque converter calculated according to the difference in gear ratio between adjacent gearshift sections. a shift amplifier determination stage that compares with the shift amplifier shift line to determine whether or not a shift amplifier is required, and issues a shift amplifier lit command signal if necessary;
and a drive means for automatically shifting gears by receiving a shift down command signal from the shift down determining means and a shift amplifier command signal from the shift amplifier determining means and driving and controlling the electromagnetic means based on these two command signals. Automatic transmission control device with