DE4110910A1 - Hydraulic control for automatic transmission of motor vehicle - corrects operation of pressure control valve to maintain required gear changing time - Google Patents

Abstract

The hydraulic control system initiates a timing interval at the beginning of gear changing and ends the timing interval upon completion of the gear change to provide a time count which is used by a storage pressure control device controlling a pressure-regulating valve for providing a counter-pressure during gear changing. The time count is compared with a required range to allow the energising level of the pressure regulating valve to be adjusted when it lies outside this range. Pref. a linear magnetic valve is used. ADVANTAGE - Prevents variation in gear changing over extended time.

Description

The invention relates to an automatic transmission, in which is a torque from the output shaft of an engine transferred to a load drive shaft and in which a Gear ratio or the ratio of the speed of the Motor output shaft with reference to the speed of the load drive shaft is changed automatically, and in particular to one Pressure control of brakes used in the transmission as well Clutches during a shift to shift shocks to suppress.

In an automatic transmission of the type specified above takes place switching from one speed range to another speed range instead of an oil pressure of at least one of the brakes and used in the automatic transmission Clutches are discharged while at least one oil pressure another of these is fed. There is a possibility and likelihood of such Switching the oil pressures can result in switching surges.  

To remedy this, according to conventional Practice memory with those used in the automatic transmission Brakes as well as clutches connected, and the back pressures on the memories are regulated so that the occurrence of bumps is prevented during a switching operation (see JP- Patent OS No. 138 553/1981). However, the scheme is under Using a mechanical valve, which is done in a rough pressure control results. It is desirable a more even, bumpless and functional pressure control to get. For this purpose, JP Patent OS discloses No. 149 657/1986 an automatic transmission in which a hydraulic circuit contains an electrically excited pressure control valve, to regulate the back pressure at storage tanks. The working game, with which the pressure control valve is electrically excited, will be in accordance with any of the following or Parameters regulated: opening of a throttle valve, a switching mode or type, an oil temperature of the engine, the cooling water temperature of the engine, the temperature of the intake by the engine Air, an oil temperature of the automatic transmission, a special position of a switch position selector switch, an engine torque, the speed of an engine, a boost pressure the engine, a fuel injection to the engine, an output torque of the automatic transmission and the speed the output shaft of the automatic transmission. To this The back pressure of a reservoir is regulated by regulating the Working cycle of the pressure control valve controlled. That leaves one fine regulation or control of the back pressure at storage tanks too because of the excitation level or the working cycle of the pressure control valve can be electrically controlled, which allows that a more appropriate back pressure at the reservoir is achieved and can be regulated evenly.

However, the tightening or engagement characteristics of frictional links, like brakes and clutches that are in the Automatic transmissions are used, or a game in  mechanical system from vehicle to vehicle and over time change so that the switching behavior that by a time which is necessary to prevent switching shocks or between Switching speed ranges is determined to differ from Vehicle to vehicle and also in accordance with the total driving time of individual vehicles changes.

It is therefore the object of the invention to make a change in shifting behavior from one automatic transmission to another to decrease and a change in switching behavior with to suppress the time.

The invention relates generally to a hydraulic control system for an automatic transmission with a hydraulic circuit for the selective supply of an oil pressure to or for the selective discharge of an oil pressure from brakes (B0-B2) and clutches (C0-C2) which are used in an automatic transmission ( 1-3 ), which is arranged between an output shaft ( 8 ) of a motor and a load drive shaft ( 39 ), with accumulators ( 260 , 270 , 280 , 290 ) in the hydraulic circuit, which are connected to the brakes (B0-B2) and clutches ( C0-C2) are connected to an electrically excited pressure regulating valve (SL6) for regulating the back pressure at the accumulators and with accumulator pressure control devices ( 130 ) which control an excitation level of the pressure regulating valve (SL6) to regulate the counter pressure at the accumulators during a switching operation the automatic transmission ( 1-3 ).

According to a first embodiment of the invention, the hydraulic control system comprises shift time determination devices ( 130 ) which determine a time interval (TT) from the triggering until the end of a shift in a mechanical clutch of the automatic transmission ( 1-3 ) during a shift process, and accumulator pressure Control means ( 130 ) responsive to a time interval (TT) determined by the switching time determining means ( 130 ) remaining in a given range (- in Fig. 10d) so as to update an excitation level (a duty cycle) of the pressure control valve that the excitation level (the work cycle) is updated to a lower value for a longer time interval and to a higher value for a shorter time interval, and also to the time interval (TT) which is outside the given range (-) by a Address non-updating of excitation level.

It should be noted that the parenthesized above Reference numbers and signs on corresponding parts or elements point out the details in the later description are explained.

The shift time determination devices ( 130 ) determine the time interval (TT) from the triggering until the end of a shift in a mechanical clutch of the automatic transmission during the shifting process. The shift time interval (TT) is determined by the mechanical engagement / disengagement that occurs in a shift mechanism. The accumulator pressure control devices ( 130 ) react to the switching time interval (TT). In particular, when the switching time interval is long, the accumulator pressure controller updates an excitation level (a duty cycle) of the pressure control valve (SL6) in one direction to decrease the time interval, that is, the duty cycle, or increase the back pressure at the accumulator. On the other hand, if the switching time interval is short, the accumulator pressure control device updates the excitation level (the work cycle) of the pressure control valve (SL6) in one direction in order to increase the time interval, ie the work cycle, or to reduce the back pressure at the accumulator.

When the tightening or engaging characteristics of in the automatic transmission used frictional links, such as brakes and Couplings, or games in the mechanical system of Vary vehicle to vehicle, so the back pressure will consequently automatically regulated at the memories so that the Switching time interval (TT) remains essentially constant. As a result, a shift shock or jerk or an overspeed (a blow-up) of the engine resulting from this change result, essentially eliminated, thereby creating a stabilized and shock-free acceleration and deceleration Responsiveness can be guaranteed. That applies in the same way even if the indentation values of Frictional links or the play between parts in the mechanical System vary over time.

However, if the frictional links used in the automatic transmission a greater degree of abrasion to one Point subject to the fact that the good switching behavior is not by means of control in accordance with the switching time interval can be maintained or if a payload or payload of the vehicle or by an incline stress is excessive, i. H. with others Words that the switching time interval (TT) from a given Area (-) comes out, the modification ends the back pressure at the accumulators in the above described Way, what an application of excessive or excessive avoids low back pressures on the accumulators. That has the effect of any disturbance in the control of the back pressure at the store under a work environment or business environment, that is outside a predetermined range is avoided. It also has an effect that a deviation of a returned back pressure memory or a switching behavior that has been traced back the gear of a preferred value within a given range can be suppressed if the operating environment  has returned to the predetermined range, such as if the frictional links have been readjusted or replaced or the payload has been removed or reduced is.

In a second embodiment according to the invention, the hydraulic control system for the above-mentioned automatic transmission comprises shift time determining means ( 130 ) for determining a time interval (TT) from the triggering until the end of a shifting of a mechanical clutch of the automatic transmission ( 1-3 ) during a shifting process , warning devices (151), a warning for an abnormal time interval (TT) dispense, and Speicherdruck- control means (130) to a specific of the switching time determination means (130) time interval (DD), which is within a first range (- in Fig is. 10d) adjacent to a reference value (TS), responsive to an excitation level (one cycle) of the pressure control valve (SL6) to update such that the excitation level for a longer time interval in a direction for shortening the time interval and for a shorter time interval in the direction to extend the time interval in In response to the time interval (TT), which is in a second range (,) which is farther than the first range (-) from the reference value (TS), is updated by the number of times (On) as this occurs is determined to count based on a count (An) which is equal to or greater than a predetermined value (step 4), and also on the time interval (TT) which lies in a third range (,) which continues from the reference value (TS) as the second area (,) is responsive to energize the warning devices ( 151 ) and the time interval (TT) that is in the second area (,) or in the third area ( ,), respond to stop updating the pressure control valve excitation level.

With this arrangement, the first embodiment of the Invention similar functions and effects achieved. In addition, an abnormality warning is issued if good switching behavior is not due to the regulation in accordance with the switching time interval as a Result of increased abrasion on frictional links, the used in the automatic transmission can be if any irregularity or deviation appears in the switching mechanism or if the vehicle's payload or due to an incline stress is excessive.

In a third embodiment according to the invention, the hydraulic control system for the automatic transmission described above comprises speed determining means ( 141 ) for determining a speed (Nt) of rotating devices ( 23 ) in the automatic transmission, the speed of which by switching oil pressures which cause braking and Couplings are guided or removed from these, is changed to effect a switching process, change rate determination devices ( 130 ) for changing a change rate (Nt2-Nt1) in the speed (Nt) determined by the speed determination devices ( 141 ), shift time Determining means ( 130 ) for determining a time interval (TT) required for the absolute magnitude of the rate of change (Nt2-Nt1) to exceed a first given value (0) and then to drop below a second given value (2,5) after the oil pressure supplied to or discharged from the brakes and clutches blocks begin to be switched responsive to a switching operation of the automatic transmission to cause (Fig. 6), and accumulator pressure control means (130) specific to the switching time detecting means (130) time interval (DD) to an excitation level ( a duty cycle) of the pressure control valve (SL6) to be updated such that the excitation level is updated for a longer time interval in a direction to shorten the time interval and for a shorter time interval to extend the time interval.

This, in turn, can also be used in conjunction with the functions and effects obtained in the first embodiment can be achieved in a similar manner.

In a fourth embodiment according to the invention, a hydraulic control system for the above-mentioned automatic transmission comprises determination devices ( 138 ) which determine the opening angle (R) of a throttle valve of the engine, speed determination devices ( 141 ) which determine the speed (Nt) of rotating devices ( 23 ), the rotational speed of which is changed when oil pressures which are guided or removed from brakes and clutches which are used in the automatic transmission ( 1-3 ) are switched over in order to effect a switching operation, detection rate change determination devices ( 130 ), which determine a rate of change (Nt2-Nt1) in the speed (Nt) detected by the speed determining means ( 141 ), switching time determining means ( 130 ) which determine a time interval (TT) for the absolute magnitude of the rate of change (Nt2 -Nt1) to exceed a first given value (0) and then go under a second counter level value (2.5) to drop after the oil pressures supplied to the brakes and clutches used in the automatic transmission ( 1-3 ), and accumulator pressure control devices ( 130 ) which can be actuated during a fixed time interval (TE) which is greater than the time interval (TT) determined by the shift time determining means ( 130 ) after triggering the switching of the brakes and clutches used in the automatic transmission to effect a shifting operation, or to be discharged from these, to an excitation level (a work cycle) to update the pressure control valve (SL6) such that the excitation level is updated for a longer time interval (TT) in one direction to shorten the time interval and for a shorter time interval to increase the time interval and can be actuated outside the fixed time interval (TE) by an excitation level (one cycle) of the pressure control valve in accordance g to be determined with the throttle valve opening (R) and the speed (Nt) in such a way that a high back pressure at the accumulator is set for a higher value of the throttle valve opening (R), while a lower back pressure is set for a higher speed (Nt) ( Fig . 9c).

With this arrangement, the functions and effects, to achieve that with the first embodiment of the invention are achieved in a similar manner. In addition oil pressures outside the switching time interval (TE) to brakes and clutches used in the automatic transmission high enough to prevent them from slipping prevent, but which are also sufficiently low to to prevent reaching excessive heights, so that abrasion or wear in the automatic transmission is avoided while saving in hydraulic Performance for the oil pressures is to be achieved.

Other objects of the invention will also be its features and advantages will be apparent from the following description attached to the Drawings make reference, clearly. It shows

Figure 1 is a schematic representation of a transmission gear mechanism in an embodiment according to the invention.

FIGS. 2a and 2b are schematic illustrations of respectively one half of a hydraulic circuit, the oil pressures to different brakes and clutches which are disposed within the gear transmission mechanism of FIG. 1 performs, or dissipates from these, FIGS. 2a and 2b along the lines 2A -2A and 2B-2B are to be joined together to form a hydraulic circuit;

FIG. 3 is a table showing the relationship between combinations of excitation and de-excitation of solenoid valves (SL1-SL3) shown in the hydraulic circuit of FIGS . 2a and 2b, around the speed range, and the engagement and disengagement of various brakes and clutches shown in Figure 1;

Fig. 4 is a block diagram of an electrical circuit for energizing the in Fig. Solenoid valves 2a and 2b shown (SL1-SL3), a solenoid valve (SL4) for controlling a lock of a timing solenoid valve (SL5) and a linear solenoid valve (SL6) ;

FIG. 5a, 5b, 5c, 5d and 5e are flow charts, the control operation (main routine) represented by a microcomputer of a control device shown in Figure 4 (130).

Figures 6a and 6b are flow charts showing the detail of "TSO, TSE Discovery" (step 64 in Figure 5d);

Figs. 7a and 7b are flow charts showing the detail "of a linear control solenoid valve" (step 65 in Figure 5d.) Play;

Figures 8a, 8b and 8c are flow charts showing the detail of "timing solenoid valve control" (step 66 in Figure 5d);

Figure 9a is a timing chart representing the timing of determination of a switching operation, a switching output and the completion of a switching process performed by the microcomputer in the control unit 130 of FIG. 4,.;

9b graphically an oil pressure outputted from the linear solenoid valve SL6, compared to the current level used to energize the coil.

9C graphically illustrates the current level used to energize the linear solenoid valve SL6 and is determined by the microcomputer in the control unit 130 on the basis of a throttle opening R and the rotational speed Nt of a disc in a clutch C1.

Is used 10a graphically a correction factor K11, which depends on an oil temperature and in determining the working cycle shown in Figure 7 (steps 117-128),.;

FIG. 10B graphically a further correction factor K12, the (steps 117-128 in FIG 7 s..) Is used as a function of the opening angle R of the throttle valve when determining the working cycle;

Fig. 10c graphically a correction factor K2 which (steps 117-128 in FIG 7 s..) Is used as a function of the switching type and the opening R of the throttle valve when determining the working cycle;

Fig. 10d is used graphically a relationship between a time reference value TS for a mechanical circuit in accordance with the opening R of the throttle valve and in accordance with areas in which this reference value;

Figure 11a graphically illustrates a change in oil pressure of a brake B0 and a clutch C2 of Figure 1 during a circuit 2 → 3, wherein the solid line represents a switching operation under power..;

Fig. 11b is a graphical representation of areas of the throttle valve and the rotational speed No of a wheel or load drive shaft are divided chosen in accordance with the opening angle R, the duty cycle corresponding to the in Fig. Controlling timing solenoid valve SL5 shown 2b in such a range Way is determined;

Figure 11c is a timing diagram for the timing when the working cycle is changed in Fig controlling timing 2b shown solenoid valve SL5 while a circuit with power from a third or a fourth speed range to a second speed range of the..;

Fig. 11d graphically shows a current example of the area division shown in Fig. 11b;

Figure 11e graphically the relationship between the areas and in Figure 11d, shown in a particular manner corresponding to a work cycle..;

Fig. 11f graphically depicts an increase in response to the oil pressure of a brake B1 (see Fig. 1.), As a result of the particular in the manner shown in Fig 11e during a circuit 1 → 2 working cycle.

Figure 11g graphically an oil pressure rise reaction of a brake B2 during a circuit 2 → 1.

Fig. 12a, 12b, 12c, 12d, 12e, 12f and 12g a number of timing diagrams showing the timing for turning on and off of the speed range-determining solenoid valve SL3 and the timing solenoid valve SL5, which are shown in Fig. 2a and 2b , during a shift from the 1.5 speed range to another as well as during a reverse shift;

FIG. 13a is a data table is referenced when a switching point X between an on / off state of the speed range caging solenoid valve SL3 is determined (see Fig 12b..);

Fig. 13b graphically shows a change in the pressures of the brakes B0-B2 shown in Fig. 1 during a 1.5 → 2 shift shown in Fig. 12b;

Fig. 13c is a table of change values to be added to the speed of the disk of the clutch C1 in a manner corresponding to the speed No of the output shaft to substantially eliminate any resulting shock during a 1.5 → 2 shift shown in Fig. 12b ;

FIG. 14a is a timing diagram showing a change in the duty cycle of the solenoid valve SL4 as a time sequence when a directly coupled clutch 50 shown in FIG. 1 is energized (or locked);

Fig 14b is graphically the operating cycle of the solenoid valve SL4 which the opening R determined according to the throttle valve and to assign Dt1. (See Fig. 14A.);

FIG. 14c is a timing diagram indicating a control effect on the working cycle of the solenoid valve SL4 in order to reduce the shocks occurring during a switching process in which the directly coupled clutch 50 shown in FIG. 1 is energized;

. 14d graphically attributable Figure the operating cycle of the solenoid valve SL4, the opening R corresponding to the throttle valve and determines to Dt2 (see Fig 14c..);

FIG. 15a graphically illustrates a set of reference travel speeds used to determine the need to perform a shift when a economy mode is not specified during the "shift decision" (step 14 in FIG. 5a);

Figure 15b graphically illustrates a set of reference vehicle speeds used to determine the need to perform a shift when a economy mode is specifically determined during the "decision for any shift" (step 14 in Figure 5a).

Fig. 1 shows the general construction of an automatic transmission in an embodiment according to the invention, a torque converter 1 with a direct-coupled clutch 50, a system constituted by an overdrive or overdrive gear auxiliary transmission 2 and an image formed by a change gear main transmission gear 3 with three forward speed ranges and a reverse speed range, which are switched in the order specified.

The torque converter 1 has a pump 5 , a turbine 6 and a stator 7 , which are assembled in a manner known per se. The pump 5 is connected to the crankshaft 8 of an engine, while the turbine 6 is connected to a turbine shaft 9 , which represents an output shaft of the torque converter 1 and also forms the input shaft of the auxiliary gear 2 , in which it is connected to the carrier 10 of a planetary gear . The directly coupled clutch 50 is arranged between the crankshaft 8 of the engine and the turbine shaft 9 . When the clutch 50 is actuated, it connects the crankshaft 8 to the turbine shaft 9 , that is to say there is a locking.

A planet pinion 14 is rotatably mounted on the carrier 10 and meshes with a sun gear 11 and a ring gear 15 . An overdrive multi-plate clutch C0 and an overdrive one-way clutch F0 are arranged between the sun gear 11 and the carrier 10 , while an overdrive multi-plate brake B0 is inserted between the sun gear 11 and a housing accommodating the overdrive gear.

The ring gear 15 of the auxiliary transmission 2 is connected to an input shaft 23 of the main transmission 3 . A forward multi-plate clutch C1 lies between the input shaft 23 and an intermediate or countershaft 29 , and a reverse multi-plate clutch C2 is arranged between the input shaft 23 and a sun gear shaft 30 . A multi-disc brake B1 is located between the sun gear shaft 30 and the housing of the transmission, while a sun gear 32 arranged on the sun gear shaft 30 has two power transmission paths of a planetary gear set together with a carrier 33 , a planet pinion 34 carried by it , a ring gear 35 meshing with this pinion, one forming further carrier 36, a support 36 carried by the planet pinion 37 and a pinion 37 meshing with the ring gear 38th A one-way clutch F1 and a brake B2 are connected between the carrier 36 and the gear housing. The ring gear 35 , which is arranged in one of the two power transmission paths of the planetary gear, is connected to the intermediate shaft 29 . The carrier 33 of this planetary gear is connected to the ring gear 38 of the other planetary gear, and the carrier and the ring gear are connected to the output shaft (load drive shaft) 39 .

In response to an output from an engine and in accordance with the driving speed becomes an automatic transmission with an overdrive unit as described above by a hydraulic control system to be explained later controlled to various clutches and brakes indent or solve, so that a shift to four Forward ranges (first, second, third, fourth Speed range: O / D) including overdrive (O / D) a forward range by a manual shift (1.5 speed range = LS) and a reverse range becomes.

A hydraulic circuit that selectively actuates clutches C0, C1, C2 and brakes B0, B1, B2 and direct-coupled clutch 50 of the torque converter in the automatic transmission to achieve an automatic shift is shown in FIGS. 2a and 2b .

The hydraulic circuits shown in FIGS. 2a and 2b include an oil tank 100 , an oil pump 101 , a pressure control valve 102 , an auxiliary pressure control valve 103 , a linear solenoid valve SL6, a manual switching valve 200 , a 1-2 switching valve 220 , a second -3 switching valve 230 , a 3-4 switching valve 240 , a ½ switching control valve SL1, a ² / ₃ switching control valve SL2, a ¾ switching control valve SL3, memory 260 , 270 , 280 and 290 , a Accumulator pressure control valve 110 , a modulator valve 90 , a throttle control valve 80 , a timing solenoid valve SL5, an idle speed modulator valve 250 , a discharge pressure valve 70 , a lock-up or engagement control valve 360 , an engagement control signal valve 370 , an engagement or Locking control solenoid valve SL4 and other hydraulic components as well as oil lines that establish connections between these valves and form a servo circuit connection for the oil pressures of the clutches and brakes.

Working oil that is pumped out of the oil tank 100 by the pump 101 is brought to a predetermined oil pressure (line pressure) by means of the pressure control valve 102 and then supplied to oil circuits or lines 104 and 105 . The oil pressure supplied via line 105 to the auxiliary pressure control valve 103 is then controlled by the linear solenoid valve SL6 to generate a torque converter pressure, a lubrication pressure and a cooling pressure which are determined in accordance with the throttle valve opening and the vehicle speed. The manual shift valve 200 connected to the oil line 104 is mechanically coupled to a shift lever located near the driver's seat, and it can be manually operated to a P-, R-, N-, D-, S- and L- Position can be set according to the range of the shift lever.

In the hydraulic circuit shown in FIG. 2, a combination in the excitation or de-excitation of the shift control valves SL1-SL3 determines a special speed or speed range of the automatic transmission shown in FIG. 1. The table in FIG. 3 shows the corresponding speed ranges, where ○ denotes the excitation and × the de-excitation of the respective solenoid valves. It should be noted that O / D, which is included in the speed range column in FIG. 3, indicates the fourth speed range (overdrive), while LS indicates a speed range that is between the first speed range (with a gear ratio of 2.905) and a second speed range (with a gear ratio of 1.530) and can be referred to as a 1.5 speed range, which has a gear ratio of 2.257.

Taking into account the features of the automatic transmission described, which are shown in Fig. 1, 2a and 2b, it should be noted that LS (1.5 speed range) lies between the first and the second speed range. The purpose of LS (1.5 speed range) is to achieve a smooth, bumpless driving behavior, which ensures a relatively high speed with sufficient performance when driving on an uphill road, and to achieve an agile, bumpless driving behavior, which ensure adequate engine braking during a downhill descent, even when the vehicle is driving on a slope with a high load, the choice of the first speed range will result in decelerated speed and the choice of a second speed range will result in insufficient performance to cause an unstable driving condition (there will be relatively frequent switching between the first and second speed ranges and this switching process easily leads to bumps) and even if the selection of the first speed range results in excessive engine braking The selection of the second speed range will result in moderate engine braking when the vehicle is driving down a downhill road (there will be a relatively frequent shift between the first and second speed ranges and such a shift will also easily cause bumps).

When an order is made around the 1.5 speed range (LS) automatically between the first and second area of the D range, the speed zones, which in the first and second speed range of the D range exist in three segments instead of divided two segments, which in a reduced width the resulting speed zones results in an increase in the frequency of switching as well as a unusual feeling on the part of the driver be what's on the resulting bumps and switching between speed ranges.

For this reason, according to the invention, the 1.5 speed range (LS) in response to a command for it 1.5 speed range, this command by a shift is given by the driver when the shift lever assumes a position within the L range.

In the automatic transmission of FIG. 1, if the sub-transmission 2 assumes an overdrive state (O / D; C0 disengaged, B0 released) and the main transmission 3 assumes a first speed range (C1 engaged, C2 disengaged, B1 released and B2 tightened), the result is Get gear ratio a value (2.257), which lies between the gear ratios (2.950 and 1.530) of the first and second speed range. As a result, this value is determined as the 1.5 speed range. If this 1.5 speed range is commanded, the auxiliary transmission 2 is in its O / D state, while the first speed range is selected for the main transmission 3 ( FIG. 3).

Another feature of the automatic transmission of FIGS. 1, 2a and 2b relates to the provision of the memories 260 , 270 , 280 and 290 , which serve to prevent the occurrence of shocks as a result of the switching operation. Each accumulator contains a piston inside, which is pushed up by a helical compression spring. The back pressure on this piston is controlled by the linear solenoid valve SL6 via the accumulator pressure control valve 110 , while the timing solenoid valve SL5 is effective to produce a quiet switching of the pressures when the associated clutches and brakes are actuated or switched off, by supplying an oil pressure to the brake B1 through the two throttles 81 and 82 (delayed increase) or by bypassing the throttle 82 (rapid increase).

In the embodiment in question, an output pressure from the linear solenoid valve SL6 (a pressure proportional thereto is supplied by the accumulator pressure control valve 110 to each of the accumulators 260-290) is essentially inversely proportional to the cycle of the current flow which excites the valve SL6. In detail, the back pressure when the working cycle of the linear solenoid valve SL6 causing current flow increases, the piston of each of the memory 260 - decreased 290, thereby causing the oil pressure of the engagement or tightening of the associated clutch or brake is reduced . In a particular shift mode or style that tends to cause shocks as a result of a shift, such shocks are prevented by determining a high cycle value for the linear solenoid valve SL6.

When the timing control solenoid valve SL5 operates to accomplish the 100% duty cycle, it connects a pilot pressure chamber of the throttle control valve 80 to a drain, whereby this valve 80 connects the line between the throttles 81 , 82 to the brake B1 (memory 280 ) bypasses. As a result, when brake B1 is released, the pressure is decreased at a rapid rate, which releases the brake quickly (or, conversely, if the brake is applied, this process will occur quickly). However, when the timing solenoid valve SL5 is turned off to effect the 0% duty cycle, the oil pressure in the pilot pressure chamber of the throttle control valve 80 increases , causing this valve 80 to connect the connecting line between the throttles 81 and 82 from the brake B1 ( Memory 280 ) separates. As a result, the brake B1 is connected to the oil pressure line by the restrictors 81 and 82 , so that the pressure when the brake B1 is released is decreased at a delayed rate (the brake is released slowly), while when the brake B1 is applied, the Pressure rises at a slow rate (the brake is slowly applied).

FIG. 4 schematically shows an electrical control system that controls the energization of the shift solenoid valves SL1-SL3, the engagement control solenoid valve SL4, the timing solenoid valve SL5 and the linear solenoid valve SL6 of the hydraulic circuit shown in FIGS . 2a and 2b.

The heart of the electrical control system is constituted by a control device (control panel) 130 , which comprises a microcomputer and an input / output interface, hereinafter referred to as ZE, which are arranged together on a printed circuit board. Connected to the input interface of the control device 130 are: a pulse generator 140 which generates electrical pulses at a frequency which is proportional to a rotational speed Ne of the input shaft 8 of the torque converter 1 (= output shaft of the motor); a pulse generator 141 which generates electrical pulses at a frequency proportional to a rotational speed Nt of the input shaft 23 (disk of C1) of the sub gear 2 ; a pulse generator 142 that generates electric pulses at a frequency proportional to an output shaft speed No (load drive shaft) 39 of the main transmission 3 ; a first speed range (LS) command switch 131 ; a fuel economy command switch 132 ; a fourth speed range (O / D) lock switch 133 ; a shift lever position detection switch 134 ; a sensor 135 detecting the temperature of the engine cooling water; a sensor 136 which detects the temperature of the oil in the oil tank 100 of the hydraulic circuit (see FIGS. 2a and 2b); a brake switch 137 ; a throttle valve opening sensor 138 ; an idle switch 139 ; an IGS switch; onboard batteries 163 and 164 .

Various input switches mentioned above are associated with associated indicator lights. When the first speed range command switch 131 is closed, thereby commanding the selection of the first speed range, a lamp 152 is lit. When the fuel economy command switch 132 is closed, thereby giving a command to drive the vehicle in a fuel economy mode, a lamp 153 is lit. When the fourth speed range lock switch 133 is closed, which commands the (O / D) to be locked accordingly, the lamp 154 is brought to light.

When the shift lever is in its neutral position N, the switch 134 will be in its N position and the lamp 155 will light. In the reverse position R of the shift lever, the lamp 156 is illuminated. The lamp 157 lights up in the parking position P of the shift lever. In the L position of the shift lever, the switch 134 is in its L position, in which the lamps 158 and 161 light up. In the S position of the shift lever, lamps 159 and 161 are lit, and in the D position of the shift lever, lamps 160 and 161 are lit. The lighting of the lamp 161 indicates that the shift lever is in a forward position. When the brake switch 137 is closed, indicating that the brake pedal has been depressed, a lamp 162 illuminates.

Electrical pulses caused by the pulse generators 140 , 141 and 142 are converted into square waves of a predetermined level by the input interface before they are connected to an external interrupt input connection of the CPU in the control unit 130 . A binary signal that goes high H for a commanded condition when the associated switch is open and goes low L. which is equal to a commanded state in which the switch is closed, e.g. B. from the first speed range command switch 131 , from the shift lever position detection switch 134 or the like. The input interface is supplied, in which a fluctuation or jump that occurs between a change in the level of the signal is eliminated by a single To deliver rising or falling pulse, which is applied to the input terminal of the ZE in the control unit 130 . Analog signals from the cooling water temperature sensor 135 , from the oil temperature sensor 136 and from the throttle valve opening sensor 138 are subjected to a smoothing and level conversion gain in the input interface before being fed to an analog signal input connection (A / D conversion input connection) of the ZE in the control unit 130 .

In response to the falling edge of a pulse generated by one of the pulse generators 140 , 141 and 142 , the CPU executes in the control unit 130 : an interrupt process to determine the engine speed Ne, the engine speed Nt of the output shaft 23 of the auxiliary transmission 2 and the engine speed No To determine load drive shaft 39 ; reading the open or closed state of the various input and detection switches, indicating the presence or absence of various commands; reading the cooling water temperature signal, the oil temperature signal and the throttle valve opening signal after their analog / digital conversion; Determining a speed range as indicated in FIG. 3; Performing a shift to the specific speed range; Detect any abnormality that occurs in the transmission; Detecting an irregularity in the water or oil temperature; Illuminate the abnormality indicator lamp 151 in a flickering manner, which corresponds to the specific abnormality whenever such is detected.

If a speed range is determined or a shift to a different speed range is effected (see FIG. 3) and if the locking is activated and deactivated, the CPU in control unit 130 performs such a process by changing and regulating the pressures supplied to the various clutches and brakes Via an output interface from this ZE, ie the solenoid valves SL1-SL3 are either switched on or off, the solenoid valves SL4 and SL5 are either switched on or off or their working cycle is regulated, and it becomes the working cycle for the current flow regulated by the linear solenoid valve SL6 in accordance with the opening angle R of the throttle valve and the driving speed No.

Controller 130 includes a memory backup circuit that maintains a memory activating voltage applied to the ZE even when the IGS switch is open, so that data written to the ZE internal memory is retained. The input switches, lamps and various sensors are connected to a signal processing circuit which is fed by a single circuit which in turn is supplied by the batteries 163 and 164 via the ignition switch IGS. On the other hand, the solenoid valves SL1-SL6 are connected to the output terminals of solenoid drivers, which are fed by a high-energy circuit, which in turn is supplied by the same batteries 163 and 164 via the ignition switch IGS. A predetermined voltage is supplied to a control signal input circuit of each of the solenoid drivers from the signal circuit. Consequently, in the time when the ignition switch IGS remains open, the energy consumption on the battery side by the memory fuse circuit and the CPU is minimal.

FIGS. 5A-5E are flow charts of a main routine of the CPU contained in the control unit 130 to execute their control operations. If the power supply to the control device 130 takes place in a step (1) in FIG. 5a (in the following, a specific step or a specific subroutine is designated with an assigned number in parentheses alone, without using the expression “step” or “subroutine”) , then the battery 163 is connected to the control device 130 . Internal registers, timers, and counters within the ZE are reset to their initial standby positions, while standby signal levels are applied to the output terminals (2). In this way, the valves SL1-SL6 are all switched off or de-energized. The battery 164 is connected in the manner shown in FIG. 4, and consequently, when the ignition switch IGS is closed and as long as it remains closed, the ZE performs a one cycle control operation through steps (3) - (79) in is shown Fig. 5a-5e, and repeats this with a TP-period.

At the beginning of the control process of one cycle, a timer TP is started (3). Then input switch, the throttle valve opening sensor u. Like. Read (4). During data processing 1 (5), inputs read in this way are written into registers referred to during the execution of a control program, and various parts are checked for any indication of an abnormality based on what this input data takes place. Whenever an abnormality is detected, the lamp 151 is made to light.

Then, during data processing 2 (6), the CPU in the controller 130 determines a current speed range based on the shift lever position, which is currently set by the automatic transmission shown in FIG. 1, and depending on whether the fuel economy command switch 132 is on - or is switched off, a possible shift type or a next speed range, on which an up / down shift from the current range, which is indicated by the content of the register PS for the current speed range, is to be carried out. In the embodiment in question, a reference vehicle speed (actually a group of reference vehicle speed values) which has a throttle valve opening as a parameter and which determines the need to perform a shift from a certain speed range (first, second or fourth gear) is used, is provided in two sentences, ie one that is used when the fuel economy mode is determined (economy mode data group: FIG. 15b) and another that is used when such driving is not determined (full throttle - or power mode data group: Fig. 15a). Accordingly, during data processing 2 (6), data indicating a possible shift mode from the current speed range is determined as well as data indicating whether or not the economy mode is used to specify a specific reference running speed group.

On the basis of the input data, which are read when the input (4) is read and written into the registers in the data processing 1 (5), the CPU in the control unit 130 then checks (7, 11) whether a 1.5- Speed range (LS) in view of the interrelation between the shift lever position (output from switch 134 ) and the presence or absence of a command for the 1.5 speed range (open or closed state of switch 131 ). In the embodiment in question, the 1.5 speed range is only achieved in the L position of the gear lever and when switch 131 is closed. In this case, 1, which indicates the need for establishing the 1.5 speed range, is written into the register LSF (12). Otherwise the register LSF is deleted (13).

During a shift decision (14), the current speed range (content of the PS for the current speed range), the content of the LSF register and the input data from the fourth speed range lock switch 133 are referred to, and the 1.5 speed range becomes reproduced Data is written into a target speed range register DS when the content of the register LSF is 1, indicating the need to set the 1.5 speed range.

If the content of the register LSF is 0, which indicates that no command is present, reference is made to data that specify a special reference vehicle speed group. Such data include those that are possible Specify switching type from the current speed range, and those that indicate whether the economy mode is used will or not.

Initially, a certain reference running speed group (one of the curves shown in solid lines in Figs. 15a and 15b) is specified from a highest (SRi speed range) of the speed ranges to which an upshifting from the current speed range (contents of the register PS) can be performed, and from which the first speed range is excluded when the lock switch 133 is closed. From this group, the value of a specific speed corresponding to the current throttle opening and representing a single point on the specific solid curve is selected and compared with a current vehicle speed No. When the vehicle speed No is equal to or greater than the reference vehicle speed value, which indicates the need for an upshift, data identifying the SRi speed range is written in the target speed range register. In the other case, such a registration is not carried out, but a similar decision is repeated for a next lower speed range.

If the need for an upshift to any speed range higher than the current range is not determined, a particular reference vehicle speed group (one of the dotted curves in Figures 15a and 15b) is determined from a lowest (SRj) of the speed ranges to which a downshift from the current speed range can be made. From this group, a value of a particular reference speed, which represents a single point on the specified dashed curve, which corresponds to the current throttle valve opening, is selected and compared with the current driving speed No. If this vehicle speed No is equal to or lower than the reference vehicle speed, which indicates the need for a downshift, data characterizing the SRj speed range is written into the target speed range register DS. If the reference driving speed is exceeded, such a registration does not take place, but a similar decision is repeated for a next higher speed range.

Note that when the switch 133 is closed, which indicates that the fourth speed range is locked, and when the contents of the current speed range register PS indicate the fourth speed range, the third speed range is written in the target speed range register DS to perform a downshift from the fourth to the third speed range.

The ZE in the control unit 130 then compares the current speed range (content of the register PS) with the content of the target speed range register DS (speed range to be achieved) and in the event that these do not correspond to one another, which indicates the need for a switching operation, the special, Speed range stored in the target speed range register DS is written into a next speed range register SS and into a next following speed range register SSN ( 15-16-17-18 ), if a switching operation is not currently being carried out. However, if a shift is currently in progress , the speed range in register DS is only written into the next speed range register SSN ( 15-16-17-26 ).

If a shift is not currently in progress, a timer TB is started ( 19 ) and 1, which indicates that the timer TB is active, is written to a register TBF ( 20 ). When the timer TB expires, the solenoid valves SL1-SL3 and the timing solenoid valve SL5 are energized to accomplish a particular speed range that is written into the next speed range register SS. A timing timer is started to achieve a smooth, smooth transition of oil pressures to the clutches and brakes during a shift, and data is entered into the various registers ( 44-54 ).

The determination of a switching time (TSO, TSE) in ( 64 ), the control of the linear solenoid valve SL6 (in 65 ), the control of the time control solenoid valve SL5 (in 66 ), the locking control (in 67 ) and the output control (in 68 ) are carried out one after the other in the order given. When the timer TP expires ( 69 ), the timer TP is restarted ( 3 ), so that the control process is triggered for the next one cycle. By repeating the control from one cycle with the TP period, the decision for a shift and the control over the up / down shift when the need for a shift is determined can be achieved smoothly in a time sequence.

The determination ( 64 ) of the switching time (TSO, TSE), which is indicated in FIG. 5d, is explained in detail with reference to FIGS. 6a and 6b. The regulation ( 65 ) of the linear solenoid valve SL6 (see FIG. 5d) is shown in detail in FIGS. 7a and 7b. The regulation ( 67 ) of the time control solenoid valve SL5 (see FIG. 5d) is shown in detail in FIGS. 8a, 8b and 8c. Nomenclatures that appear in these figures are explained below.

LSF: a register for storing information indicating the presence or absence of a command for the 1.5 speed range. If its content is "1", then there is a command for the 1.5 speed range, which means that "0" indicates the absence of such a command.
PS: a register for the current speed range, which has a content which indicates a current speed range of the automatic transmission of Fig. 1, including a park state P, a reverse state R, a neutral state N, a first, a 1.5- , a second, a third or a fourth speed range.
DS: a register for temporary storage of a speed range (a first, 1.5, a second, a third or a fourth speed range), which is determined by the shift decision to be accomplished.
SS: a next speed range register for storing a speed range (a first, 1.5, a second, a third or a fourth speed range) to be formed. A type of switching is determined by the contents of the registers PS and SS.
SSN: a next following speed range register for storing a speed range, which is to be established following a shift from PS to SS.
TBF: a flag register that indicates whether the timer TB is in operation or not. Its content "1" indicates that the timer is working, and "0" indicates that the timer TB is not operating or has not been started.
TEF: a flag register that indicates whether the timer TE is in operation or not. Its content "1" indicates that the timer is working, and "0" indicates that the timer TE is not in operation or has not been started.
PUF: a flag register for an upshift under power (gas supply). Its content "1" indicates that there is an upshift or shift to a higher speed range under the condition that a driving load is applied to the engine, while "0" a downshift or a shift to a lower speed range or an upshift under no load condition on the engine (gas supply switched off, which means that the vehicle is idling or coasting or there is engine braking).
TEIF: a flag register that indicates the start of a switching time. The content "1" indicates that there is a state immediately after the timer is started.
FEFF: a flag register that indicates that a state exists immediately after the switching period has ended. The content "1" indicates that it is in a time interval that follows the expiration of the timer TE, but is before the expiration of a timer T2D.
i, j: a number register in which the number of times is entered with which a power or full throttle state (a drive load is imparted to the engine) or a powerless state (gas supply switched off) has been determined.
k: a number register for storing a number of times that the inequality is Nt1 <Nt2, where Nt2 represents a current Nt, while Nt1 denotes the value of Nt that previously prevailed on a TP, which is used to determine the start of a shift becomes.
TTF: a flag register which marks the end of the determination of the switching time. Its content "1" indicates that the determination of the switching time TT has ended, while "0" indicates that the determination of the switching time has not yet been completed.
TCR: a flag register that indicates an abnormality in the switching time TT when it has a value of "1".
CR: a register into which data are entered that indicate the suitability or adequacy of the switching time TT.
POI: a flag register that indicates the need to determine an output value for the duty of the linear solenoid valve SL6, indicating the completion of the determination of the output value when the content is "1".
ADMEM: a register for storing a learned value for the working cycle of the linear solenoid valve SL6.
ADIN: a register for storing a calculated value of the working cycle for the linear solenoid valve SL6.
ATIN: a register for storing a calculated value of the working cycle for the time control solenoid valve SL5.

In the following, the control operation of the invention Embodiment explained in detail.  

(1) Determination of Ne, Nt, No

Immediately after the ignition lock switch IGS is closed, the CPU starts in the control unit 130 of a program timer with three time limits (timers 1-3), which enables an interrupt process in response to a pulse supplied by one of the pulse generators 140 , 141 and 142 . For example, in response to the falling edge of a pulse caused by the pulse generator 140 , the CPU enters an interrupt process in which a count register 1 is incremented, followed by a check as to whether the timer 1 has expired or not. If the timer has not expired, the CPU returns to a special control process that is accepted before the interrupt process begins. If the timer 1 has expired, the content of the counting register is written into a register Nef, which is used to calculate a rotational speed Ne, while the timer 1 is started again and the CPU returns to the previous control. In response to the falling edge of a pulse caused by the pulse generator 141 , the CPU enters an interrupt process in which a count register 2 is incremented by one, followed by a check as to whether the timer 2 has expired or not. If the timer has not expired, the CPU returns to its control that existed before the interrupt process started. If the timer 1 has expired, the content of the counting register 2 is written into a register Ntf for calculating a speed Nt. The timer 2 is started again and the ZE returns to its previous control. In response to the falling edge of a pulse generated by the pulse generator 142 , the CPU enters an interrupt process in which a count register 3 is incremented by one, followed by a check as to whether the timer 3 has expired or not. In the negative case, the ZE returns to its previous control, which existed before the interrupt process started. If, on the other hand, the timer 3 has expired, the content of the counting register 3 is written into a register Nof for calculating a rotational speed No, the timer 3 is started again and the CPU returns to its previous control.

As a result of the execution of these interrupt operations, the number of pulses generated by the respective pulse generators 140 , 141 and 142 during a last given time limit is written into the registers Nef, Ntf and Nof. During data processing 2 in FIG. 5a ( 6 ), the CPU in the control unit 130 calculates speeds Ne, Nt and No on the basis of data stored in the registers Nef, Ntf and Nof, which represent the number of pulses generated in a specific time limit. and writes them into the speed registers Ne, Nt and No, respectively. In this way, the last or updated speed information is maintained in these speed registers.

(2) Summary of timing from the determination the need for a shift to completion of the switching process

For an upshift, timer TB is started ( 19 ) when the need for a shift is decided as indicated by the white triangle in Fig. 9a. When the timer runs out, the energization of the solenoid valves SL1-SL3 is switched so that a next speed range is established ( 43-48 ). This time is indicated by a black triangle in FIG. 9a and is referred to as "switching output". For example, for a circuit from 2 → 3, the excitation / de-excitation of the solenoid valves SL1-SL3 is regulated in accordance with the D-3 line shown in FIG. 3. Then the timer TE is started ( 46 ).

In this embodiment, TB = 0.2 s. TE is chosen to be 0.8 s for a downshift from 4 → 3 and 1.5 s for other upshifts and downshifts. This TE value is set to be greater than a sum TSE of a time TSO which elapses from the output of the switching output ( 48 ) until the actual mechanical switching process is initiated, and a time TT from the initiation of the mechanical switching until its completion. It should be noted that a mechanical switching time represents the real switching time.

(3) Determination of a mechanical switching time TT

A mechanical switching time TT changes with wear on friction elements of the automatic transmission and with one associated with driving the vehicle Burden. If such a time is too short, it will be greatest Probability of a shift shock or jerk to occur. On the other hand, if this time is too long, an overspeed may occur of the engine or poor acceleration the result be. In view of these disadvantages, the mechanical one Shift time a measure of the value or preference of the automatic transmission.

For the present invention, for an upshift from 1 → 2 or 2 → 3, the mechanical switching time TT is determined after the timer TE has started. This determination is shown in detail in Fig. 6a. In particular, the initiation of a mechanical circuit is determined in such a way that it must take place after a reduction in the speed Nt following two or more TP periods, and the determination of the mechanical switching time TT is initiated at ( 81-87 ). A mechanical circuit is determined to terminate in units of a TP period in response to a decrease in a new Nt value that is 2.5 RPM or more less than a previous Nt value. The value TT thus set is written into the register TT ( 88-90 ), and 1 is written into the flag register TTF ( 91 ) to indicate the completion of the determination of the time TT.

(4) Determine an error in the transmission using the mechanical switching time TT

When a load associated with driving the vehicle is abnormally high, when frictional members such as clutches or brakes are subjected to a greater degree of wear in the automatic transmission of Fig. 1, when some kind of abnormality develops within the transmission mechanism or the vehicle drives irregularly or if a fault or an abnormality appears within the transmission mechanism, the mechanical shift time TT will become excessively long or extremely short, which creates the possibility of a shift shock or an overspeed of the engine. In order to counter this, eight areas or zones are determined according to the invention - around a basic switching time (fixed value) TS using the throttle valve opening R as a parameter, as shown in FIG. 10d. A switching time TT which is determined is checked to see which zone it is in ( 92 in Fig. 6b), and if it is in a zone or, 1 is written to the abnormality register TCR ( 103 ), which is a Indicates abnormality by lighting lamp 151 ( 104 ). If the switching time TT is determined to be in a zone or lying, the number of times An with which this is determined is counted. If this number An is less than 4, 2 is written into the degree of adequacy register CR ( 99-102 ). If the number of times is equal to or greater than 4, an operation takes place in the same way as if the switching time is in a zone or. If the switching time falls in a zone or, the abnormality is deleted ( 96 , 97 ) and 1 is written into the adequacy degree register CR ( 98 ). If the switching time is in a zone or, the abnormality register is cleared ( 93 , 94 ) and 0 is written into the register CR while clearing this register ( 95 ). As a result, the data in the registers CR and TCR reflect the degree of appropriateness or suitability of a switching time.

(5) Multiple switching

If there is a change in the throttle valve opening or the driving speed No during a time interval (TB + TE) from deciding the need a switching process until the actual termination of this Switching process is present, it may be necessary to switch to a speed range that during that of the interval (TB + TE) updated speed range is different.

When the necessity for a switching operation during an interval TB, which means the time interval from the start of the timer TB until its expiration, is determined, a speed range for which the necessity for the completion has been determined is written into the next speed range register SS ( 23 in Fig. 5b). As a result, the speed range that was written to this register SS immediately before the TB interval occurs is now cleared as a result of this writing, and therefore that for the speed range when the timer TB expires ( 48 in Fig. 5c ) available switching output is effective to establish a speed range that is determined during the TB interval.

If it is decided on the necessity of a switching operation during the switching time or during the time that the timer TE is running, following the TB interval ( 15-16-17 ), it should be noted that the immediately preceding switching operation has ended. Accordingly, the next speed range to be accomplished is written in the next speed range register SSN ( 36 ), and when the timer TE expires, a switching output is output to output the speed range for which the need for a switching operation has been recognized ( 41-42 -55-46-57-58-44 to 48 ). In other words, this means that the switching to the speed range takes place immediately after the previous TE without adding another TB interval.

(6) Determine an upshift under power

A shift shock is likely to occur during a power shift (TE), while an engine overspeed is likely to occur during a powerless upshift. Accordingly, during an upshift (TE), the rate at which the oil pressure is changed is determined in a manner that corresponds to the condition with or without power (full throttle or idle gas), thereby avoiding the occurrence of a shift shock or engine overspeed. For this purpose, the determination of the condition with or without performance is necessary. This is preferably done immediately before switching (TE), since the throttle valve opening R, the driving speed No, the speed of the engine Ne and change from time to time. Accordingly, the invention is carried out the determination of the condition under power or without power during the TB interval according to (16-23 to 35). It should be noted that the decision to use empty gas is also made during the TE interval ( 17-36-30 to 35 ).

In particular, if Ne ≧ Nt during the TB interval (TBF = 1) is considered to be a switching mode during an upshift, the content of the number register i is incremented by one ( 16-23-24-27-28-29 ). If the content of register i is equal to or greater than 2, then 1, which represents the power upshift, is written into the flag register PUF ( 31 ). If this happens in the TB or TE interval, then the content of the number register j is decremented by one if Ne <Nt ( 32, 33 ), and if the content of the register j is equal to or greater than 2, it will Flag register PUF deleted ( 35 ). if the register is cleared, it means that the no-power mode prevails. In this way, if the shift type is an upshift, the state with or without power is determined in succession until the timer TB expires, whereupon the powerless state (empty gas) is recognized. If a decision is made on the power status, the content of the register PUF is set equal to 1, while it is equal to 0 when the powerless status is recognized. Accordingly, when the switching output is given ( 48 ), information is stored in the register PUF which indicates whether or not the condition is under power.

(7) steady state control of the working cycle for the linear solenoid valve SL6 ( Fig. 7a and 7b)

The linear solenoid valve SL6 develops an oil pressure that is substantially proportional to the magnitude of the current flowing through its electrical coil, and an oil pressure proportional to this pressure is applied to the accumulators 260-290 by the accumulator pressure control valve 110 as the piston back pressure. The relationship between the magnitude of the current flow through the coil of the solenoid valve SL6 and the back pressure on the piston of the accumulators 260-290 is shown graphically in FIG. 9b. According to the invention, the size of a current flow through the solenoid valve SL6 is determined by the working cycle. The relationship between the cycle and the mean current flow is also shown in Fig. 9b.

The linear solenoid valve SL6 is used as a replacement for a conventional throttle valve, which is used in the conventional hydraulic circuit, which is mechanically connected to the rotary shaft of a throttle valve and responds to the control pressure, which in turn depends on the speed of the engine, so that a line pressure can be adjusted which corresponds to the throttle valve opening and the control pressure. At a predetermined point in time, principally during the TE interval in a special manual transmission, the CPU in the control unit 130 regulates the work cycle in order to control the back pressure, as explained in the following paragraph ( 8 ), so that the back pressure of the accumulators 260 -290 is regulated so as to prevent the occurrence of a shift shock . At other times, however, the ZE causes excitation with a current level (or with a corresponding work cycle), as shown in FIG. 9c, ie in a manner corresponding to the throttle valve opening R and the speed Nt of the output shaft of the auxiliary transmission 2 . In particular, a pressure that corresponds to the throttle valve opening R and the rotational speed Nt is applied to the accumulators 260-290 and to the 2 → 3 changeover valve 60 ( 115 , 116 in FIG. 7a).

(8) The back pressure control on the accumulators during a switching operation ( Fig. 7)

For an upshift 1 → 2, from 2 → 3 or from 3 → 4 under power (PUF = 1), in order to prevent the occurrence of a switching shock, during the switching interval (TE: see FIG. 9a), if it currently prevails , the working cycle of the linear solenoid valve SL6 or the back pressure on the piston of the accumulators 260-290 essentially determined as follows:

K1 × K2 × [K3 (1-TT / TS) + ADMEM]

Here are:

K1 is a milieu or environment change correction factor which is given by K1 = K11 + K12, K11 representing an oil temperature correction factor and K12 a correction factor corresponding to the throttle valve opening,
K2 is a correction factor corresponding to the type of shift and the throttle valve opening, and
K3 is a correction factor that corresponds to the switching type. The values of these correction factors are shown in FIGS. 10a, 10b, 10c and 10d.

The correction factor K11 is calculated in a manner that corresponds to the temperature determined by the oil temperature sensor 136 ( 118 in FIG. 7b). The correction factor K12 is calculated in a manner corresponding to the throttle valve opening R ( 118 ). The correction factor K2 is calculated in a manner corresponding to the throttle valve opening R and the type of shifting ( 120 ). The correction factor K3 corresponds to a 1: 1 relationship to the switching type, and consequently a value corresponding to the switching type or the content of the registers PS and SS is selected.

TT represents the last mechanical switching time TT or an indication which is determined by the flow diagram shown in FIG. 6a and is stored in the register TT, while TS denotes a basic switching time (fixed value). ADMEM represents the work cycle that is determined by the correction that occurs as a result of a learning effect.

The CPU in the control unit 130 calculates

K1 × K2 × [K3 (1-TT / TS) + ADMEM]

in the manner described below. Initially, the learned value ADMEM or the content of the register ADMEM is converted into an appropriate value [K3 (1-TT / TS) + ADMEM] in a way that corresponds to the last mechanical switching time TT and the prevailing switching mode, after which this value is converted into the ADMEM register is written to update ( 126 ). The current environmental factor K1 (= K11 + K12) and the correction factor K2 are multiplied by the data stored in the register ADMEM, and the product is output as an output working cycle which is written into an output register ADIN which is intended for the linear solenoid valve SL6 ( 128 ). During the output control ( 68 in FIG. 5d), the ZE in the control unit 130 outputs an on / off signal with the working cycle, which is reproduced by the data stored in the output data register ADIN, to the solenoid driver, which is assigned to the excitation of the solenoid valve SL6 is.

When the batteries 163 and 164 are connected to the control device 130 , energy is supplied to it, and when the ignition lock switch IGS is subsequently closed, control for the automatic transmission shown in FIG. 1 is enabled or triggered for the first time. If this triggering occurs, a learned value is not available for the working cycle of the SL6 solenoid valve. As a result, the value 0 is contained in the POI register. Accordingly, if the content of the POI register is 0, an initial value (fixed value) is written in the ADMEM register to write 1 in the POI register, indicating that the initial value has been established ( 122 , 123 ). Since the learned value does not have to be updated at this time ( 126 ), such an update does not take place and ADMEM multiplied by the environmental factor is used to determine the working cycle ( 124 ).

As mentioned in paragraph (4) above, in the event of an error occurring within the transmission, the shift time TT is shifted from the reference value TS. As a result, it is inappropriate to modify the learned value for the working cycle ( 126 ). In this respect, reference is made to the degree of adequacy of the switching time TT (content of the registers TCR and CR), and if the switching time TT is in one of the zones,, or ( FIG. 10d), the learned value ( 126 ) is not modified, however the prevailing working cycle (ADMEM) is corrected by a value that corresponds to a change in the milieu or the environment in order to determine the working cycle for the linear solenoid valve SL6 ( 125-128 ). Thus, the learned value of the working cycle is only modified if the switching time TT is in one of the zones. This ensures a uniform automatic pressure control (or correction of the working cycle) as a time sequence only within a suitable range of the shift behavior (TT) of the automatic transmission, in order to bring the shift time TT closer to the suitable value TS.

The Fig. 11a shows a change in a time series in the oil pressure of the brake B1, and the oil pressure of the clutch C2 during a 2 → 3 circuit. In this figure, the oil pressure of the brake B1 is indicated with a solid line for a power condition and with dashed lines for a powerless condition. The oil pressure for clutch C2 is shown for the performance state with a thick, solid line and dashed single and colon lines, while the oil pressure for the inoperative state is not shown.

Depending on the working cycle of the linear solenoid valve, which is caused by the back pressure control of the accumulator is obtained, which is only during of the performance state, the oil pressure in the clutch increases C2 rapid on and the switching time TT is short when the work cycle is low, as shown by the dashed colon line is. In contrast, the increase occurs for a high work cycle of the oil pressure of clutch C2 slowly, as by the single point Line is indicated, which causes an increase in the switching time TT becomes. During the powerless state is in the time of the switching process the working cycle made 0, which is why the oil pressure clutch C2 rises as quickly as possible and the neutral range shown shorter than shown in the drawing.

In this respect it can be seen that the mechanical switching time TT depends on the work cycle and assumes a longer value for a higher work cycle and a shorter value for a lower work cycle. During the back pressure control of the accumulator, a correction + K3 (TS-TT) / TS or a correction corresponding to a deviation of the current switching time TT from the reference value TS is added to the previous working cycle in order to generate the next working cycle ( 126 in FIG. 7), with which a modification of the learned value is carried out. In this way, the mechanical switching time TT converges to the reference value TS. In this respect, the work cycle is automatically adjusted in accordance with a change in the engagement or tightening behavior of the frictional engagement members, such as the clutch C2 and the brake B1, in response to their abrasion to actually keep the shift time at the reference value TS, so that the occurrence of a Switching shock is prevented.

(9) Control of the timing solenoid valve SL5

Solenoid valve SL5 determines the rate at which the oil pressure applied to brake B1 increases and the rate at which the oil pressure drops when brake B1 is released. The brake B1 is only applied in the second speed range (see FIG. 3), and consequently the increase or decrease rate of the oil pressure of the brake B1 is controlled in a shift mode that is related to the oil pressure of the brake B1, thereby causing a shift shock to occur is prevented.

For a 2 → 3 position (see FIG. 11a), the time control solenoid valve SL5 remains switched off for the power time ( 131-132-135-145 -return in FIG. 8a), so that the bypass valve 80 closes the line, which bypasses the throttle 82 . Since the brake B1 is connected to the 2 → -3 switching valve, which connects it to the outlet (low pressure) through the throttle 81 and 82 , the rate at which the brake B1 is relieved is therefore low. If there is a change from the state with power (PUF = 1) to the state without power (PUF = 0) during the time interval after the TE interval has been reached and until the time elapses 0.1 s, the CPU switches in the control unit 130 the timing solenoid valve SL5 when the timer T1 expires ( 132-145 to 147 : a dashed slope that occurs 0.1 s later in the SL5 line in Fig. 11a). In particular, a work cycle of 100% data is written into the output register ATIN connected to the time control solenoid valve SL5 31670 00070 552 001000280000000200012000285913155900040 0002004110910 00004 31551 ( 147 ). The time limit T1 (0.1 s) can be changed to various values in the range 0.1-0.3 s. When the timing solenoid valve SL5 is turned on, the bypass valve 80 opens the oil line bypassing the throttle 82 so that the brake B1 is depressurized at a higher rate. When the TE interval has elapsed , the time control solenoid valve SL5 is switched off or its working cycle is changed to 0% ( 131-149-156 (in FIG. 8c) - 157-159 ). In Fig. 11a is a change in the pressure of the brake B1 is shown during the performance time by a solid line. At the output ( 68 in FIG. 5d), the CPU in the control unit 130 relates to data stored in the output register ATIN connected to the timing control solenoid valve SL5 and outputs an on / off signal with the work cycle indicated by this data to the solenoid valve SL5 associated solenoid driver.

During a 2 → 3 shift, if this happens in the de-energized state, the ZE switches the time control solenoid valve SL5 (on the work cycle of 100%) when the TE interval ( 134 ) occurs and switches it on (on the work cycle from 0 %) after the lapse of the TE interval from ( 131-149-156 (in Fig. 8c) -157-159 ).

The time control for energizing the solenoid valve SL5 during a shift to the second speed range in the power state (full throttle) is shown in FIG. 11c. During a shift to the 2nd speed range, the throttle valve opening R and the speed No of the output shaft 39 of the main transmission 3 are checked to determine in which of the ranges I-IV and the unregulated range, respectively, which are shown in Fig. 11b, their Combination lies during an interval A, which covers a period of 0.4 s after entering the TE interval ( 131-132-135 to 139 ).

If the combination is found to be in area I, the working cycle for the time control solenoid valve SL5 is selected to be 100% ( 140 ). The working cycle is selected with 65% if the combination is in area II ( 141 ), with 50% for area III and with 0% (switched off) for area IV ( 143 ). FIG. 11d shows an actual delimitation of the areas I-IV, and FIG. 11e graphically shows the relationship between the area in which the combination is determined to be lying and the corresponding work cycle. In an interval B ( FIG. 11c ), which lies in the TE interval, but after the initial 0.4 s have elapsed, a decision is made in which of the areas I-IV or in the unregulated area, that in FIG. 11b and more precisely in FIG. 11d are shown, the combination of the throttle valve opening R and the speed No of the output shaft of the main transmission 3 is. A difference is expressed and tested in terms of this area between an area As determined as containing the combination and an area Ap previously determined ( 138 ). If the difference corresponds to two areas or more, the work cycle is decided to correspond to the new area As ( 139-140 to 143 ). If the difference expressed in the form of these areas is 1 or less, the working cycle remains unchanged ( 133-144 ). A change in the pressure of the brake B1, which results from such a regulation of the working cycle, is shown graphically in FIG. 11f.

For an upshift under power, the time control solenoid valve SL5 (on the work cycle of 100%) is switched on with a 2 → 3 or 2 → 4 shift ( 132-145-146- 133-134 ).

For a switching of 2 → 1, the time control solenoid valve SL5 is switched off (or on the work cycle of 0%) until the end of the switching process or until the TE interval has elapsed while it is switched on (set to the work cycle of 100%) when the switching operation is completed, as shown in Fig. 11g. As a result, the oil pressure of brake B2 assumes a high value in order to transfer the maximum torque in the first speed range to TE (1.5 s). Since the oil pressure is changed to a pressure used in the first speed range at TE after the switching process, the oil pressure of the brake B2 is low immediately after the switching process or within the TE interval, which prevents the occurrence of a switching shock.

(10) Control of the excitation of the time control solenoid valve SL5 when the shift lever is switched from the D or S position to the L position ( FIG. 8a)

When the manual shift lever is shifted from the D or S position to the L position, the ZE writes in a manual shift determination register 1 and starts a timer T20a, which has a time limit T20a of 2 s ( 131-149-150-151 ). When the timer expires, the ZE switches on the time control solenoid valve SL5 (to the work cycle of 100%) and clears the manual shift determination register ( 131-149-150-152-153 to 155 ). As a result, when the shift lever is switched from the D or S position to the L position, the oil pressure of the brake B2 will rise to a value in order to then transmit the maximum torque used in the first speed range after T20a (2 s) . Since the oil pressure of the brake B2 has been kept low up to this time, no shock results from a change in the oil pressure. The occurrence of a shift shock is also prevented if a shift to the first speed range takes place in connection with a shifting of the shift lever to the L position.

(11) Shift control with respect to the 1.5 speed range (LS)

The first to third speed range is accomplished by keeping the auxiliary gear 2 low (SL3: off; the expression "high / low" refers to a speed range of the output shaft of the auxiliary gear 2 and "low" corresponds to a high gear ratio) and by in the main gear a speed range is established, which is determined by the combination of the on / off of the solenoid valves SL1 and SL2. The fourth speed range (O / D) is determined by holding the auxiliary transmission 2 high (SL3: on, corresponding to a low gear ratio) and by establishing the third speed range (SL1, SL2: off) in the main transmission 3 . Accordingly, switching between the first to third speed ranges actually means switching between speed ranges of the main transmission 3 (single shift change).

However, the 1.5 speed range is determined by holding the secondary gear 2 high (SL3: on) and the first speed range in the main gear 3 (SL1: off / SL2: on). Accordingly, a shift between the speed range of 1.5 on the one hand and the second and third speed ranges on the other hand is a double shift change, which makes it necessary to shift both the main transmission 3 and the secondary transmission 2 .

1 → 1.5 circuit

FIG. 12A shows a timing for the solenoid valves during a 1 → 1,5-circuit. With this shift mode, the main transmission 3 remains in the first speed range, while the auxiliary transmission 2 is shifted from its low state (SL3: off) to its high state (SL3: on), which therefore represents a single shift change. During this switching mode, the time control solenoid valve SL5 remains switched on (at the work cycle of 100%). The solenoid valves SL1-SL3 are switched from their on / off setting, which is used to accomplish the first speed range, when entering the TE interval or when the timer TB expires, to the setting effecting the 1.5 speed range. In particular, the SL3 is switched from its off to its on state.

The linear solenoid valve SL6 is energized with a working cycle or with a current value shown in FIG. 9c, which corresponds to the throttle valve opening R and the rotational speed Nt of the output shaft 23 of the auxiliary transmission 2 , until the end of the TB interval, but upon entering the TE -Interval, the working cycle is set to a value that prevailed immediately before. In other words, the excitation takes place with a fixed work cycle during the TE interval.

1.5 → 2 circuit

Fig. 12b shows the timing of the solenoid valves during a 1.5 → 2 shift. This shift type represents a double shift change, in which the main transmission 3 is switched from the first to the second speed range and the secondary transmission 2 from its high to the low state. During this switching mode, the timing solenoid valve SL5 is turned off (on the duty cycle of 0%) at a time when this switching is determined ( 15 to 22 in Fig. 5b), and when the TB interval has passed, a determination of the special range in which the combination lies, as previously described with reference to FIG. 11b, and the solenoid valve is energized with a working cycle corresponding to the range determined in this way ( 148-136 to 144 in FIG. 8b). The linear solenoid valve SL6 is controlled in a similar manner to the 1 → 1.5 switching mentioned above.

The shift solenoid valves are changed as follows with this switching mode: SL1: off, SL2: on, SL3: on (these conditions prevail in the 1.5 speed range) to SL1: on, SL2: on, SL3: off (these conditions prevail in the second speed range). When entering the TE interval, the ZE initially switches on both solenoid valves SL1 and SL2 in preparation for the production of the second speed range, but delays the switchover of the solenoid valve SL3 to its off state. The ZE then calculates a difference or an inequality between the main transmission and the secondary transmission from their synchronization ΔN = Nt-1.53 No between the speed Nt of the output shaft of the secondary transmission 2 and a speed 1.53 No, which is on the input shaft of the main transmission 3 (or the output shaft of the auxiliary transmission 2 ) is generated if this is at no. On the other hand, the ZE selects a reference value (Gmap value: Fig. 13) that has the speed No as a parameter and turns off the solenoid valve SL3 at a time (point X) when the inequality ΔN ≦ Gmap applies to the second speed range accomplish. FIG. 13a shows values for Gmap.

In the 1.5 speed range, the auxiliary transmission 2 is held high in the same way as in the O / D (fourth speed range) and the main transmission is set in the same way as in the first speed range. Accordingly, a 1 → 1.5 and a 1.5 → 1 shift can be accomplished by merely switching the sub gear from its high to its low state or vice versa. However, for a 1.5 → 2 or a 1.5 → 3 gear shift, it is necessary that the auxiliary transmission 2 be switched from its high to its low state and that the main transmission be switched from the first to the second or third speed range, which increases the possibility is caused that switching shocks can be caused in two stages, ie for each of the two transmissions. Consequently, during the 1.5 → 2 shift, the solenoid valve SL3 is switched off at the point in time (point X), since ΔN ≦ Gmap is applicable in order to establish the second speed range. The purpose for this is to be seen in achieving a substantial synchronization of the termination of the switching operations both in the auxiliary transmission 2 and in the main transmission 3 .

The Fig. 13b schematically shows the timing diagram for the 1,5 → 2 circuit in detail. When the solenoid valve SL3 is switched off at the ΔN value shown in FIG. 13c in the 1.5 → 2 switching (it should be noted that because SL1 as well as SL2 are switched on, switching off SL3 brings the second speed range) , Switching operations in the main transmission 3 and in the secondary transmission 2 will be terminated essentially in a synchronized manner, which prevents the occurrence of switching shocks. The ΔN value that allows this synchronization characteristic to be achieved has No as a parameter as shown in Fig. 13c and Gmap has a value close to the ΔN value as in the rightmost column of Fig. 13c (and Fig. 13a). Since the point X, at which the solenoid valve SL3 is switched off, is chosen such that the current value of Δ N is not greater than the Gmap value (reference value), it follows that switching operations in the main transmission 3 and auxiliary transmission 2 are essentially synchronized Ended way, which mainly prevents the occurrence of switching shocks.

1.5 → 3 circuit

This type of shifting is a double shift change, which requires the shifting of the main transmission 3 from the first to the third speed range and the change of the auxiliary transmission 2 from its high to its low state. Such control is similar to that used during the 1.5 → 2 shift described above, but with this shift type it is selected that ΔN = Nt-1.00 × No.

1.5 → 4 circuit

The timing during this type of switching is shown schematically in Fig. 12c. This shift type is a single shift change, with the main transmission being shifted from its first and third speed ranges while the secondary transmission 2 remains in the high state.

If it becomes necessary to select this type of switching, when the timer TB ( 15-22 in FIG. 5b) is started, the time control solenoid valve SL5 is switched off (to the operating cycle of 0%) and after the switching operation has ended or at the end of the TE -Intervals kept off. The on / off status of the solenoid valves SL1-SL3 is changed when the TE interval is entered. The control of the working cycle of the linear solenoid valve SL6 remains the same as the 1 → 1.5 circuit mentioned above.

1.5 → 1 circuit

The timing control during this type of switching is shown in Fig. 12d. This type of shifting is again a single shift change, the auxiliary transmission 2 being changed from its high to its low state, while the main transmission 3 continues to be operated in the first speed range. The timing control solenoid valve SL5 remains switched off with this type of switching (based on the operating cycle of 0%), while the on / off state of the solenoid valves SL1-SL3 always changes to the state that is used during the first speed range when entering the TE -Interval is changed. The linear solenoid valve SL6 is excited with a work cycle or current value shown in FIG. 9c, which also corresponds to the throttle valve opening R and the rotational speed Nt of the output shaft of the auxiliary transmission 2 during the TE interval.

2 → 1.5 circuit

FIG. 12e shows the timing during this switching type, which is a double circuit changes, whereby the main gearbox 3 is switched from the second to the first speed range, while the sub-transmission is 2 changes from its low to its high state. With this type of switching, when the TE interval is entered, the on / off states of the solenoid valves SL1 and SL2 are changed from those assigned to the second speed range to those assigned to the 1.5 speed range (even if used in the first speed range as far as the main transmission 3 is concerned), however, the valve SL3 becomes from off to high state (or from low to high in the secondary transmission 2 ) only after T15S (0, 4 s) has elapsed or only after the timer T4 (0.4 s), which is started in step 49 in FIG. 5c, has switched over. In other words, when entering the TE interval, the first speed range is established first and then the 1.5 speed range is achieved in T15S. The time control solenoid valve SL5 remains in its switched-off state (on the working cycle of 0%) until TDL (2 s) elapses when entering the TE interval, after which it is switched on (on the working cycle of 100%). The linear solenoid valve SL6 is excited with the working cycle or the current value shown in FIG. 9c, which also corresponds to the throttle valve opening R and the rotational speed Nt of the output shaft of the auxiliary transmission 2 during the TE interval.

3 → 1.5 circuit

The timing of this type of switching is shown schematically in Fig. 12f. This type of shifting is a double shift change, the main transmission 3 being switched from the third to the fourth speed range, while the auxiliary transmission 2 is changed from its low to its high state. Specifically, this control is similar to that used in the 2 → 1.5 circuit.

4 → 1.5 circuit

Fig. 12g shows the timing in this circuit. Even though this type of shift is a single shift in which the main transmission 3 is shifted up from the third to fourth speed range while the auxiliary transmission remains in the high state, it is obtained by initially achieving a change from the fourth to third speed range by the secondary transmission 2 changed from its high to low state or, in an equivalent manner, the solenoid valve SL3 is switched from its on to its off state, as shown in FIG. 12g. When the TE interval elapses, timer T2 (0.2 s) and timer T2D (0.2 + TDL s, where TDL represents a delay time) are started ( 55-63 in Fig. 5c). When timer T2 expires, the 1.5 speed range is established ( 70-79 in Fig. 5e). In particular, the solenoid valve SL3 is switched from its off to its on state, while the solenoid valve SL2 is brought from its off to its on state. In other words, the auxiliary transmission 2 changes from its low to its high state and the main transmission 3 is switched from the third to the first speed range. The timing control solenoid valve SL5 remains off (at 0% duty cycle) until timer T2D expires, whereupon it is turned on, ie at 100% duty cycle ( 72-76 in Fig. 5e). ATIN represents the output register connected to the solenoid valve SL5. The linear solenoid valve SL6 is energized with the working cycle or a current level, which is shown in FIG. 9c and corresponds to the throttle valve opening R and the rotational speed Nt of the output shaft of the auxiliary transmission 2 during the switching process .

(12) steady state lock control

In the lock controller ( 67 ) shown in Fig. 5d, when the solenoid valve SL4 is off or the lock in which the directly coupled clutch 50 is engaged and the solenoid valve SL4 is in the on state is not activated, a special reference speed data group that has the throttle valve opening R as a parameter, specified to determine the activation of the lock depending on an affected speed range, assuming that the shift lever is in its D position and the brake switch 137 is turned off, that is, the brake pedal is not depressed . From this data group, specific reference speed specifications are specified which correspond to the current throttle valve opening R, and the current driving speed No is checked whether it is equal to or greater than the reference speed specification. If it appears that the current driving speed No is equal to or greater than the reference speed specification, this means that there is a need to activate the lock. As a result, the lock is activated by energizing the solenoid valve SL4. However, in order to avoid any shock resulting from the lock, the duty cycle of the solenoid valve SL4 is gradually increased as shown in Fig. 14a. In particular, if the necessity for the locking turns out, a working cycle Dt1 corresponding to the current throttle valve opening R is determined and written into the output register ALIN. The relationship between the throttle valve opening R and the working cycle Dt1 is shown graphically in FIG. 14b. Timers TLB (0.4 s) and TLON (1.0 s) are started. The same cycle is then maintained until the TLB timer expires, provided the locked state continues to exist. When the timer TLB expires, an operating cycle Dt1 ( FIG. 14b) corresponding to the then prevailing throttle valve opening R is calculated again, and the operating cycle is updated to this newly calculated value. If the TLON timer expires, the working cycle is changed to 100%. This ends the lock activation control to engage the direct-coupled clutch 50 .

During locking and during locking Activation control is the current driving speed No monitors for a state to complete the interlock given is. In particular, a special reference speed is Data group that the throttle opening as a parameter specified to complete the termination locking depending on the particular To determine the speed range. Special reference speed information, that of the current throttle valve opening R are specified in this data group, and the current driving speed No is checked, whether it is equal to or less than the reference speed is. In the case because the current driving speed No equal to or less than the reference speed specification the locking must be ended will. As a result, the solenoid valve SL4 is switched off, d. that is, brought to the working cycle of 0%. To do this a working cycle of 0% characterizing information in the output register ALIN assigned to the solenoid valve SL4. However, in order to swing or commute between activation and termination of the lock to prevent making the decision about the need the lock does not end during an interval 0.5 s after the TAON timer has expired or after the lock activation control ends executed.

If it becomes necessary to complete the interlock before the TLON timer expires during the interlock activation control, the solenoid valve SL4 is immediately switched off (brought to the operating cycle of 0%). If there is a need for a switching operation before the timer TLB expires, the solenoid valve SL4 is switched off immediately. If a need arises for a switching operation after the TLB timer has expired, but before the TLON timer expires, the control described in the next paragraph ( 13 ) is performed.

(13) Control of excitation of the lock- Control solenoid valve SL4 when a switching operation to be carried out during locking

When entering the TE interval for the control of an upshift, the CPU in the control unit 130 once reduces the work cycle of the solenoid valve SL4 which brings about the locking and then increases this gradually, so that the work cycle returns to 100% after the TE interval has elapsed , as shown in Fig. 14c, to enable switching surges can be absorbed by the torque converter 1 to a certain degree. In particular, when the TE interval is entered, the working cycle of the locking solenoid valve SL4 is reduced to Dt2, which corresponds to the prevailing throttle valve opening R, and the timer TLS (0.4 s) is started. The Fig. 14d is a graph showing the relationship between the throttle opening and the working R game Dt2. When the timer DLS expires, a work cycle Dt2 is calculated again, which corresponds to the prevailing throttle valve opening R, and the work cycle of the solenoid valve SL4 is updated to this calculated value. At the end of the TE interval, the working cycle of the SL4 solenoid valve is reduced to 100%.

For a downshift, when entering the TE- Interval the solenoid valve SL4 switched off immediately or brought to the working cycle of 0%. Subsequently the latch will be in accordance with the above Paragraph (12) activated.  

(14) Locking control in connection with a change in the gear lever position

When the brake switch 137 is turned on, which means depressing the brake pedal, or when the shift lever is switched to one of its S, L, N, R, or P positions, the locking is instantly terminated by turning off the solenoid valve SL4.

If the shift lever is in its S position, the lock is activated in accordance with the lock activation control described in paragraph (12), provided that No ≧ 700 rpm, the idle switch 139 is closed, which indicates an idle state, and at the same time Ne <Nt is fulfilled. When the shift lever is shifted from the S position to a different range when a change occurs that causes No <700 RPM or when the idle switch 139 is opened (by opening the throttle valve), the lock becomes ended immediately by switching off the solenoid valve SL4.

As described, the ZE in controller 130 writes 1 to register LSF when the L range shift lever position detected by switch 134 and LS (1.5 speed range) command switch 131 are closed, indicating the presence of a such a command ( 7-11-12 ), and during the shift decision ( 14 ), a 1.5 speed range is written in the register DS as a speed range to be done next, and it is determined that there is a need for a shift ( 15 ) if the current speed range represented by the contents of the register PS is different from the 1.5 speed range stored in the register DS, due to which the shifting is carried out from the current speed range which the first, second, third or fourth speed range can be followed by the 1.5 speed range ( FIGS. 12a, 12e, 12f or 12g).

Then, when the switch 131 is opened, indicating the lack of the command for the 1.5 speed range, or when the shift lever is switched from the L position to the S or D position, the LSF register is cleared ( 7, 11 - 13 ), and during the switching decision (14) a special speed range (range X) in the S or D range, which corresponds to the current throttle valve opening R and the speed No of the wheel or load drive shaft, is determined and written into the register DS with which a circuit of 1.5 → X is carried out, where X = 1, 2, 3 or 4 (see FIG. 12b, 12c or 12d).

Subsequently, as long as the shift lever is in the D range, there is only a shift between the first, second, third and fourth speed ranges. If the shift lever is in the S range, the shift takes place between the first and second speed range. When switch 131 is open, indicating the absence of any command for the 1.5 speed range, only the first speed range in the L range is established. In these cases, the 1.5 speed range is not achieved.

According to the invention, at the beginning of a switching operation initiated a time counting operation when the absolute Size of a rate of change in the speed Nt of a disk a clutch C1 exceeds 0 and it will exits when the absolute size in case it once increased is decreased below 2.5. The counted time TT represents a time interval that is required  to switch a gear ratio. To the appearance to prevent switching surges caused by a change in the shift behavior of the automatic transmission can be the working game with which a a linear solenoid valve determining a storage back pressure SL6 is excited, adjusted so that the counted time TT is obtained, which is equal to a reference value TS, where, if the counted time TT versus a large deviation the reference value TS shows the adjustment of the working cycle brought to a standstill and a warning lamp came on becomes.

The invention was based on a preferred embodiment described and illustrated. However, it is clear that the invention through the details disclosed herein in is not restricted in any way and is known to the person skilled in the art Modifications and changes are suggested in the teaching taught are, however, as within the scope of the invention are to be viewed falling.

Claims (4)

1.Hydraulic control system for an automatic transmission with a hydraulic circuit for the selective supply of an oil pressure to or for the selective discharge of an oil pressure from brakes (B0-B2) and clutches (C0-C2) which are used in an automatic transmission ( 1-3 ), which is arranged between an output shaft ( 8 ) of a motor and a load drive shaft ( 39 ), with accumulators ( 260, 270, 280, 290 ) in the hydraulic circuit, which are connected to the brakes (B0-B2) and clutches (C0-C2) with an electrically excited pressure control valve (SL6) for regulating the back pressure at the accumulators and with accumulator pressure control devices ( 130 ) which control an excitation level of the pressure regulating valve (SL6) in order to control the back pressure at the accumulators during a switching process of the automatic transmission ( 1- 3 ) to be regulated, characterized by

• - Shift time determination devices ( 130 ) which determine a time interval (TT) from the triggering until the end of a shift in a mechanical clutch of the automatic transmission ( 1-3 ) during a shift process, and
• - accumulator pressure control means ( 130 ), responsive to a time interval (TT) determined by the switching time determining means ( 130 ), which is in a given range (- in Fig. 10d), to an excitation level of the pressure control valve in accordance with a update such a time interval that the excitation level is updated for a longer time interval in a direction that shortens the time interval and for a shorter time interval in a direction that extends the time interval, the accumulator pressure control devices updating the excitation level whenever the specific time interval (TT) exits the given area.

2. Hydraulic control system for an automatic transmission with a hydraulic circuit for the selective supply of an oil pressure to or for the selective discharge of an oil pressure from brakes (B0-B2) and clutches (C0-C2) which are used in an automatic transmission ( 1-3 ), which is arranged between an output shaft ( 8 ) of a motor and a load drive shaft ( 39 ), with accumulators ( 260, 270, 280, 290 ) in the hydraulic circuit, which are connected to the brakes (B0-B2) and clutches (C0-C2) with an electrically excited pressure control valve (SL6) for regulating the back pressure at the accumulators and with accumulator pressure control devices ( 130 ) which control an excitation level of the pressure regulating valve (SL6) in order to control the back pressure at the accumulators during a switching process of the automatic transmission ( 1- 3 ) to be regulated, characterized by

• - Shift time determining devices ( 130 ) for determining a time interval (TT) from the triggering until the end of a shift in a mechanical clutch of the automatic transmission ( 1-3 ) during a shift process,
• - warning devices ( 151 ) which give a warning that the determined time interval (TT) is in an abnormal range, and
• - accumulator pressure control means (130) responsive to said certain of the shift time detecting means (130) time interval (DD), which is within a first range - that address is close to a reference value (TS) to an excitation level (in Figure 10d.) of the pressure control valve (SL6) to be updated in accordance with such a time interval that the excitation level for a longer time interval in one direction to shorten the time interval and for a shorter time interval to extend the time interval in response to the time interval (TT) occurring in one second range (,), which is farther than the first range (-) from the reference value (TS), is updated to count the number of times (On) since this occurrence is detected, and also to the Time interval (TT), which in a third area (,) which is further from the reference value (TS) than the second area (,), responds to the warning device en ( 151 ) to excite, wherein the memory pressure control devices stop updating the excitation level when the determined time interval is in the second or third range.

3.Hydraulic control system for an automatic transmission with a hydraulic circuit for the selective supply of an oil pressure to or for the selective discharge of an oil pressure from brakes (B0-B2) and clutches (C0-C2) which are used in an automatic transmission ( 1-3 ), which is arranged between an output shaft ( 8 ) of a motor and a load drive shaft ( 39 ), with accumulators ( 260, 270, 280, 290 ) in the hydraulic circuit, which are connected to the brakes (B0-B2) and clutches (C0-C2) with an electrically excited pressure control valve (SL6) for regulating the back pressure at the accumulators and with accumulator pressure control devices ( 130 ) which control an excitation level of the pressure regulating valve (SL6) in order to control the back pressure at the accumulators during a switching process of the automatic transmission ( 1- 3 ) to be regulated, characterized by

• - Speed determination devices ( 141 ) for determining a speed (Nt) of rotating devices ( 23 ) in the automatic transmission, the speed of which by switching oil pressures, which led to the brakes (B0-B2) and clutches (C0-C2) or by these are removed, is changed to effect a switching operation,
• - Change rate determination devices ( 130 ) which determine a change (Nt2-Nt1) in the speed (Nt) determined by the speed determination devices ( 1431 ),
• - Switching time determination devices ( 130 ) for determining a time interval (TT) required for the absolute magnitude of the rate of change (Nt2-Nt1) in order to exceed a first given value (0) and then to drop below a second given value (2,5) after the oil pressures supplied to or discharged from the brakes and clutches start to be switched to effect a shift, and
• - accumulator pressure control means ( 130 ), responsive to the time interval (TT) determined by the switching time determination means ( 130 ), to update an excitation level of the pressure control valve (SL6) such that the excitation level for a longer time interval in one direction to shorten of the time interval and for a shorter time interval to extend the time interval.

4.Hydraulic control system for an automatic transmission with a hydraulic circuit for the selective supply of an oil pressure to or for the selective discharge of an oil pressure from brakes (B0-B2) and clutches (C0-C2) which are used in an automatic transmission ( 1-3 ), which is arranged between an output shaft ( 8 ) of a motor and a load drive shaft ( 39 ), with accumulators ( 260, 270, 280, 290 ) in the hydraulic circuit, which are connected to the brakes (B0-B2) and clutches (C0-C2) with an electrically excited pressure control valve (SL6) for regulating the back pressure at the accumulators and with accumulator pressure control devices ( 130 ) which control an excitation level of the pressure regulating valve (SL6) in order to control the back pressure at the accumulators during a switching process of the automatic transmission ( 1- 3 ) to be regulated, characterized by

• - determining devices ( 130 ) which determine the opening angle (R) of a throttle valve of the engine,
• - Speed determination devices ( 141 ), the speed (Nt) of rotating devices ( 23 ) in the automatic transmission ( 1-3 ), the speed of which is changed when using brakes (B0-B2) and clutches (C0-C2), which are used in the automatic transmission ( 1-3 ), oil pressures which are guided or discharged by them, in order to effect a shift process,
• Change rate determining means ( 130 ) which determine a rate of change (Nt2-Nt1) in the rotational speed (Nt), which are detected by the rotational speed determining means ( 141 ),
• Determination devices ( 130 ) which determine a time interval (TT) for the absolute magnitude of the rate of change (Nt2-Nt1) in order to exceed a first given value (0) and then reduce it to a second given value (2,5), after the oil pressures supplied to the brakes and clutches used in the automatic transmission ( 1-3 ) start to be switched to effect a shift, and
• - Accumulator pressure control devices ( 130 ) which can be actuated during a fixed time interval (TE), which is greater than that determined by the shift time determination devices ( 130 ), from the start of the changeover of the brakes and clutches used in the automatic transmission to a shifting operation cause, to or from these oil pressures discharged time interval (TT) to update an excitation level of the pressure control valve (SL6) such that the excitation level for a longer time interval (TT) in a direction to shorten the time interval and for a shorter time interval updated to increase the time interval and actuated outside the fixed time interval (TE) to determine an excitation level of the pressure control valve in accordance with the throttle valve opening (R) and the speed (Nt) such that a high back pressure at the accumulator for a higher value of Throttle valve opening (R) tight is underway while a low back pressure is set for a higher speed (Nt).