Method for shifting speeds in automatic or automated mechanical synchromesh gearbox of automobile

专利摘要:
The functions M(y) and M(n) between the torque M of the engine, the position y of the accelerator pedal and the speed of rotation n are stored in an electronic control unit (13), in which the moment values pertaining to the measured acceleration signal and to the measured speed of rotation signal are picked out and a load signal s is generated. The signal s is compared with a constant shifting-up load value Sf and with a constant shifting-down load value Sv, and a command for shifting of gears (2) and friction clutch (3) is given to the servo unit (14). …<IMAGE>…
公开号:SU1752182A3
申请号:SU884356679
申请日:1988-10-14
公开日:1992-07-30
发明作者:Шимоньи Шандор；Терочик Ласло；Валоци Дьердь
申请人:Чепел Аутодьяр (Инопредприятие)；
IPC主号:

专利说明:

Fig /
the measured speed signal, and based on their comparison, a load signal s is generated. The load signal s generated in this way is again compared by the load estimator with a signal expressing a constant value of the comparison — increase of the step-load sf, H cjcnmanoM sr, expressing the constant value of the step-load decrease. The rotation speed signal is also compared by means of a rotation speed estimator with a signal expressing a constant value nf of the step-increase ratio — the speed number and a signal expressing a constant value pg of the step-speed reduction ratio. When the load signal s drops below the value of the signal expressing the value of sf, the increase in the load-level is increased, and when the speed signal increases, the value of the signal expressing the comparison nf value — increase in the speed-speed number by the switching unit 14, a command is issued to switch to a higher level, and when the load signal s is increased, the value of the signal expressing the magnitude of the comparison-dropping sV value, or when the speed signal decreases lower value signal expressing the magnitude comparing pg -ponizheni chisll-stage speed using a switching control unit of n stages switching device 11 a command is switched to a lower step. 8 hp f-crystals, 15 il, 1 tab.
The invention relates to a method by which it is possible to determine the optimum value of a point of change of a step transmission in automobiles. This method can be used in automatic transmissions and in manual transmissions with automatic transmission.
The purpose of the invention is to increase efficiency by determining the optimal gear shift point for any load. -
FIG. 1 is a block diagram of a bus drive line; in fig. 2 - the diagram the number of turns - the engine moment; in fig. 3-diagram accelerator pedal position - engine torque; in fig. 4 is a block diagram of a variant of the electronic control unit; in fig. 5 is a graphical depiction of conditions depending on the speed and load; in fig. 6 is a graph of comparisons of the positions on the diagram number of revolutions — torque of the engine and hydrodynamic torque converter; in fig. 7-15 is a block diagram of devices characterizing variants of the method.
The proposed method can be implemented in several versions and can be used both in automatic transmissions and in automated mechanical synchronized transmissions. To implement the invention, an electronic unit has been created, the operation of which is carried out according to the program laid down in it, depending on the corresponding variant of the method and with the corresponding gearbox. Further, the main option is considered, and when describing other options, only differences are described. For a clearer understanding, the simpler and then more complex operations of the method, and each operation in a separate flow chart, are described first. For these reasons, block diagrams are depicted as
so that their construction is well perceived and visually.
A practical implementation of the method used in the city bus driven by engine 1, as seen in FIG.
1. It is a six-cylinder diesel engine with a power of 140 kW, the accelerator pedal position diagram is the moment (M f (())) of which is shown in Fig. 2, and the number of turns diagram is the moment (M f (n) in Fig. 3 .
The idling speed is 500/550 rpm, the minimum operating speed is 880 rpm, the maximum speed is 1800 rpm, and the maximum speed is 2200 rpm.
Engine 1 drives gearbox 2 (FIG. 1). It is an automatic transmission with planetary gears and four steps (four forward speeds and one reverse) The gear ratio of these gears is as follows: 3.43; 2.01; 1.42; 1.00. The input shaft of the box is connected by a hydrodynamic transducer 3 moments and a short
its friction clutch A with the crankshaft of the engine 1. The switching of the stages and the disengagement-clutch of the friction clutch is strengthened by means of an electromagnetic valve. The theoretical average speed of the steps is: when switching from the lowest to 2 speeds of 18 km / h, to speed 3 - 25 km / h, to speed 4 - 40 km / h, when switching from highest to speed 3, 85 km / h at 2-22 km / h, at 1-3 km / h. The final speed of the bus is 80 km / h.
The output rail of the box 2 is connected by the drive shaft 5 to the differential 6 of the rear axle, and the differential 6 is connected by semi-axes 7 to the wheels 8. The units listed form a known bus drive line.
The proposed method is also applicable in passenger cars. As is known, the gearbox and differential in passenger cars with front-wheel drive and rear-mounted engines generally form a block in which there is no driveshaft.
One of the essential types of information from the point of view of the choice of speed is how the driver comes to the decision to switch the speed. For this purpose, a switch 9 for selecting steps, i.e. controller made in the form of a handle or a button. Using the controller, you can issue commands to the following gear positions: the gearbox is in the idle or neutral position N includes not more than 1 gear, includes not more than 2 gears, includes not more than 3 gears, includes direct gear D i. in 4th gear, engages reverse gear R, engages in position P a hundred-night brake. The outputs I, II, III, D, R, P of the switch 9 are connected to the corresponding inputs of the electronic control unit. The electronic control unit 10 is used to control the solenoid valve 11, and the information needed for control is provided by signal sensors.
In fact, in the proposed method, it is not necessary for the driver to prohibit the switching of one or several stages in the controller. Correctly determining the conditions for shifting to a higher gear excludes the presence of such incorrect positions when shifting to a lower gear that can be eliminated only by external influences (I, II, and III controller positions). Thus, these positions may not be necessary. However, these prohibition provisions should be retained for a single reason; in the event of certain violations of the operation of the automatic transmission control, the vehicle with these prohibition positions is still controlled from the manual control so that it can be delivered to the repair location.
Other information is supplied by the sensor.
0 12 signals on the accelerator pedal position, built into this pedal 13, which regulates the fuel supply system of the engine 1, the total angle of this pedal 13 is 23 ° and over this whole range from 0 to 23 °
5, the sensor 12 outputs an electrical signal proportional to the angular position of the pedal. Sensor 14 is also connected to the input of the electronic control unit. Finally, the necessary information and to control
0 represents the number of revolutions of the engine 1. The signal of the speed of nm, expressing the number of revolutions of the crankshaft of the engine 1 and suitable for control, is generated by the sensor 14 of the signal about the speed,
5 mounted on the camshaft of the engine 1 and connected to the input of the electronic control unit 10. A 1: 2 transmission of the camshaft and crankshaft is taken into account immediately after entering the
0 electronic unit 10. The electronic unit 10 can be performed in countless ways. One option is shown in FIG. 4. Electronic elements have known types of designations in accordance with the catalogs of integrated circuits,
The electronic unit 10 (Fig. 4) consists of a microprocessor Z 80 A IC1, a programmable I / O unit P10 8255 IC2 and
0 IC3, programmable three-channel counting unit IC4 (8252), random access memory (RAM) C5 (4016), read-only memory ROM (ICG), (2732), clock pulse generator IC7 (7434), reset unit IC8 (74 LS132) and decoder IC9 (74LC 138).
Address inputs, data inputs and control inputs of the same destination in
0 microprocessor IC1, programmable input-output unit IC2 and IC3, programmable three-channel counting and storage unit IC4, RAM 1C5, ROM IC6 and decoder 09 are interconnected.
5 The reset unit 108 is connected to the microprocessor 1C1 reset point, IC2, IC3 and IC4 blocks. The outputs of the decoder IC9 are each connected to the corresponding input of blocks IC2, IC3. IC4, IC5 and IC6. The clock pulse generator IC7 is connected to the clock input of the microprocessor IC1 and IC4.
The electronic control unit 10 is connected to the elements involved in the control as follows.
Signals from the outputs of switch 9 are received at the inputs of the programmable I / O unit IC3, the signal from sensor 12 of the signal about the accelerator pedal position and the signal from sensor 14 of the number of revolutions are fed to the inputs of the programmable three-channel computational block IC4,
The control signal of the electronic unit 10 appears at the outputs of the programmable input-output unit IC2. These outputs are connected via power amplifiers 15 and 16 to the electrical input of the solenoid valve 11. Power amplifiers 15 and 16 are not included in the electronic unit 10,
In the diagram of FIG. 4, it is not possible to accurately identify those blocks which are further referred to in the description of the variants of the methods and the associated flow diagrams. This is explained by the fact that electronic units with elements corresponding to the operations performed can be constructed in a simpler way. It is obvious, for example, that a single high capacity storage unit is capable of accumulating the information for which there are separate storage units in the block diagram,
In accordance with the scheme in FIG. 7, the proposed method is performed as follows.
In memory block 17, a diagram M is entered (ip, shown in Fig. 2 and expressing the relationship between the accelerator pedal position and torque, and in the memory block, a diagram (n) in Fig. 3, expressing the relationship between speed and torque.
In the general case, the switching of the stage occurs as follows. When the driver wants to start driving, he switches the switch 9, which was previously in the idle position N, to position I. If the conditions for complete driving safety of the bus are met, the driver adds the engine 1 speed by pressing the accelerator pedal 13 and block 19 switching steps, sends to the solenoid valve 11 through the power amplifier 20 a command and switching on the 1st gear. Thus, the bus starts driving on 1st gear.
From now on, the accelerator pedal position sensor 12 continuously outputs a throttling signal to the memory unit 12, and the rotational speed sensor continuously outputs
speed signal per memory block 18. Memory unit 17 selects theoretical instantaneous values related to the accelerometer pedal position from the M (p) diagram entered into it. Similarly, the memory block 18 selects from the M (n) chart entered therein the instantaneous values related to the number of revolutions. From comparing these two instantaneous values
It can be concluded about the load of the engine 1. This is accomplished by block 21. generating a load signal, since it receives both the signal from memory block 17 and the signal from memory block 18, Here, using the formula
.
Q SMQ) dy) -SM (n) dn. 1PPO, SM (p) dpUO /
The load signal S is generated as a percentage. This load signal S changes with the accelerometer pedal position and the net speed is almost constant.
The load signal S is supplied from block 20.
generating this signal, in block 21 load assessment. Thus, a rotation speed sensor signal 14 is applied to the rotation speed estimator 22. The evaluation of the load signal S and the rotation speed signal nm is visible
of figs. 5. Experimentally determined the values of load and speed, with the simultaneous occurrence of which it is possible, without reducing the speed of the bus, switch to a higher gear. Similarly, the values of load and speed are determined, at which it can be shifted to a lower gear, otherwise, the movement of the bus will unreasonably slow down, or the engine will stall.
From FIG. 5 that the gearbox must switch to the next higher gear if the load decreases below a constant
the magnitude of the comparison — increase the load-load stage sf, where sf is 25%, and if the engine speed exceeds a constant value nf of the comparison — increase the gear speed, the number of revolutions, where nf 1200 rpm. Of
Fig 5 shows that switching to a higher gear level can be performed in the range F.
The conditions for downshifting are:
the load value is higher than the constant value sv of the comparison-lowering of the stage-load, where sv is 50%, or the number of revolutions of the engine is lower than the constant value nv of the comparison-lowering stage, where
nv 870 rpm These conditions are indicated in FIG. 5, a region of lowering of the level v.
Thus, the load estimation unit 21 controls where the actual load signal S is in the load range from 0 to theoretically 100%, and if the signal expressing the magnitude sf of the comparison of the step-load increase is reduced, a signal is generated that expresses the need for switching to a higher gear, And if the load signal exceeds a signal expressing the magnitude sv of the step-load increase, then a signal is produced that expresses the need to shift to a lower gear, which is transmitted to the block to 19, controlling the gear shift.
Similarly, an estimate of the speed signal nm occurs in block 22, which estimates the speed, which controls where the speed lies in the range from 0 to 2200 rpm. If the actual number of revolutions is higher than the value of nf compared to the increase of the step-speed, a signal is generated that expresses the need to shift to a higher gear, and if the actual number of revolutions is lower than the value of the comparison-reduction of the stage-speed, then a signal is produced that expresses the need downshift, which is transmitted to the block
20 shift control.
If the load value S and the actual number of revolutions fall into the range F, indicated in FIG. 5, the gearshift control unit 18 outputs through the amplifier 15 to the solenoid valve
21 commands to disable 1 transfer and the inclusion of 2 transfer
During this gear change, the friction clutch 3, for the reasons that will be described, is in most of the cases in the on position. Therefore, the problem of the mentioned asynchrony arises here. The hydraulics cause a response delay, and this makes it necessary to have an element in the electronic unit that provides a delay of 50 ms. In this way, overlapping switching also takes place here.
The gearshift control unit 19 issues, in the same way as described, a command to switch on 3 and A gears if the load S and the actual speed, in accordance with the driver's desire to start acceleration, fall into the upshift range F again (Fig. 5 ).
the gearshift control unit 19 needs a built-in memory into which the step identification signal is inputted. By this
it is ensured that the gear control unit, along with an estimate of the need for a shift to a higher or a lower stage, can also decide which gear
0 must be enabled. In addition, unit 19 must have the ability to decide which transmission corresponds to the actual speed of the car, if necessary, change the gearbox 2 gears during
5 movements at idle speed, and then, with continued movement, switch back to any level.
Although knowing the actual speed of a car is not necessarily necessary for
0 of the proposed control, this task is not completely performed by block 19 and therefore the gearbox 2 is fitted with a speed sensor, which will be described in more detail when looking at another option.
In order to perform gear changes, it is necessary to pay attention to the coupling and disengagement of the friction clutch A B in order to determine the
0 conditions are required prior; by reference
As is known, the ability to transmit a moment of a hydrodynamic moment converter 3 is different from the moment
5 created on the crankshaft of the engine 1. These two points are equal at about 1000 rpm, with a smaller number of revolutions, the ability of the hydrodynamic converter to transfer the moment is lower, and
0 with a higher number of turns, the diagrams of the moments (n) of the hydrodynamic moment converter used in our case were not taken, so that only the relation is shown in Fig. 6
5 diagrams of engine torque 1 and hydrodynamic converter 3. Engine diagram 1 is designated as Mmot and hydrodynamic converter diagram is Mnct Thus, if in a range of less than 1000 rpm, friction clutch 3 is not short-circuited, hydrodynamic torque converter 4 has slipping, then engine 1 of bus 7 mokhet keep working on that
5 same transfer. Obviously, at a higher number of revolutions, the small slip created by the hydrodynamic converter represents an unnecessary loss, therefore it is advisable to close the friction clutch 3.
The operating conditions of the friction clutch 3 are determined as shown in FIG. 5, as follows.
The friction clutch 4 closes if the rotational speed exceeds the constant value pg of the comparison short circuit the number of revolutions where PG 1100 rpm and the load value decreases below the constant value of the comparison short circuit closure of the load where, and the number of turns is disconnected decreases below a constant value, comparing the number of revolutions, where 900 rpm each.
It can be seen that the revolutions do not fall within the 1000 r / min value corresponding to the intersection points of the moment curves, since in this way the operation of the friction clutch is more definite.
To accomplish this, i.e. to control the clutch friction clutch 4, the load signal produced by block 20 is supplied to load evaluation unit 23, and the speed signal nm from sensor 14 is sent to turn speed estimator 24, which is compared with the short-circuit comparison value sr or load the value of pg comparison - short circuit - the number of revolutions and the magnitude of the reference value-comparison - the number of revolutions. If the load value s decreases below the comparison value sr - short circuit - load, and the rotational speed rises above the comparison value pg - short circuit - rotational speed, the load estimation unit 23 and the rotational speed evaluation unit 24 provide a signal to the friction clutch control unit 25, expressing the need for this short circuit, and the friction clutch circuit control unit 25, through the amplifier 16, issues a command to short circuit the electromagnetic valve 11 that controls the friction one clutch 4. The clutch 3 closes, i.e. between the crankshaft of the engine 1 and the input shaft of the gearbox 12 is mechanically connected.
FIG. 5 shows that the magnitude of the comparison of short circuits of the load is more rigid than the magnitude of the comparison sf - increase of the step-load, while the magnitude of the comparison pg - short circuit - speed number is softer than the value of nf comparison - increase the step - number turns. Those. while engine load 1 is intense, i.e. you need a hydrodynamic converter 8 moment, if, for example, the driver wants to increase the speed of the car, the first step will increase, and if the load is more
then the frictional short circuit will first occur.
There are three reasons for lowering the gear stage: when
the driver slows down or speeds up sharply (when overtaking), or the bus goes up.
The simplest case is when the driver slows down. Here he releases the accelerator to the starting position, after which the number of revolutions of the engine 1 falls. When the number of revolutions decreases below the magnitude of the comparison of the number of revolutions, the unit 24 for estimating the number of revolutions
5 issues to the clutch closure control unit 25 a signal expressing the need to disengage the friction clutch 4, and the clutch closure control unit 25 issues a command to release the electromagnetic valve that controls the friction clutch through the amplifier 16. The clutch opens and thereafter the moment transfer occurs through hydrodynamic converter 3 points.
5If the engine speed 1 continues to decrease and decrease below the value nv of the comparison-reduction of the speed-number of revolutions, the engine speed evaluation unit 22 generates a signal expressing the need to reduce gear, after which the amplifier 15 gives the electromagnetic valve 11 a command to turn on the 4th gear and to turn on 3 assists.
5 If the driver continues to reduce the speed, the gearshift control unit 19 issues, with a decrease in the number of revolutions of the engine 1, a similar command to further decrease the steps.
0With active acceleration and when moving up, the position is different. There may be a state of unreliable switching, which until now has simply been eliminated by the action taken.
5 in one or two steps of a certain tightening of the switching conditions to a higher level. In the proposed method, the conditions for raising the stage by means of monitoring the state of the load before lowering the stage are tightened only at the required scale smoothly,
In order to implement the method, it is necessary to first determine the kind and measure of such tightening. To do this, it was experimentally established that the sf value of the comparison - increase of the step - load should be tightened to a maximum of 6%, i.e. the corrected sfK value of the comparison - increase of the step-load should be between 25 and 6%.
The tightening measure should be selected depending on the degree of load before lowering the step. Since the rotational speed signal is one of the initial information values of the load, it is enough to check how high the number of revolutions of the engine 1 was at the time the stage was lowered, or where one was in the range of working revolutions. In the engine used in this case, this range is 880-1800 rpm. In the first approximation between finding the number of revolutions in the working range before lowering the stage and tightening the conditions for increasing the stage, a linear relationship is allowed. Experimental MRNT is shown that no adjustment is required. However, it is advisable to establish accurate communication empirically.
In the case of a linear relationship, the adjustment is performed using the following formulas:
y - nzur u ck
Pimin
Pymax Ptsmin
where K is the correction factor;
Dzurtfck - the number of revolutions before lowering the stage;
pCmin is the minimum operating speed (800 rpm);
Pimaks - the maximum working speed (1800 rpm).
SK K (sf-ZTmin),
where sK is a correction value;
K — said correction factor;
sf is the normal value of the comparison - increase of the step-load (25%);
sfwHH is itself a hard value of the comparison-step-load increase (6%).
Finally
sfK sf-sK, srK sr-sK,
where sfK is the corrected value of the comparison-increase of the step-load;
srK is the corrected value of the comparison short circuit of the load.
The rotational speed outputted by sensor 14 is permanently memorized by memory unit 26. If the driver begins to overtake, he strongly presses the accelerator pedal 13. The change in the pedal position corresponds to the higher value from the function M ((p)), therefore the load signal s generated by the block 20 rises and, when it reaches the value of sv, the step switching control unit 19 gives in an electromagnetic manner
valve 11 is a switching command down one step.
At the same time, the step switching control unit 19 outputs to
block 26 command to memorize the newly received signal of the number of revolutions. On this signal, in block 27, generating a comparison-load signal, a correction value sK is generated in accordance with
these formulas and is applied to the load estimator 18 and further to the load estimator 23.
From this point on, the load estimation unit 21 compares the signal arriving
from block 20, generating a load signal, with that signal, which expresses the corrected sfK value of the step-load comparison-corrected corrective value and indicates to block 19
control of gear change, the need to increase transmission by one gear only if this strict condition is met.
Similarly, the load evaluation unit 23 indicates to the clutch closure control unit 25 that such a closure is necessary only if the load signal is less than the srK value corrected by the correction value sK
szmzneni -short closure -loads. At the end of overtaking or acceleration, engine speed 1 advances the gas pedal position, the load signal s decreases and, if it falls below the corrected sfK value, load evaluation unit 21 indicates to the step control unit the need to increase transmission by one step.
Switching control unit 19
steps, extinguishes the correction value sK with its team, and the initial conditions of the friction clutch transmission and short circuit steps are returned. When the bus goes on the rise, basically the same process takes place. Here, the load signal s does not change due to the decrease in engine speed 1, memory 22 selects a lower moment from the diagram M (n) and the load signal s rises along with the constant position of the accelerator pedal and, if sv comparison of step-load lowering, the load estimation unit 21 indicates the switching control unit 19
the steps need to lower the steps, and the step switching control unit commands to switch to a lower step. At the same time, the described process begins.
Changing the conditions for switching steps, of course, is possible not only with a change in the sf value of the comparison — increase of the step-load, but also with a change in the value of nf — of the comparison — increase of the step-speed ratio. This can be done as follows.
The adjustment factor is the same as before, thanks to
nK K (nfMaKc-nf), where pc is a correction value;
hammock - the most rigid value of the comparison — raising the speed-speed (1700 rpm);
nf is the normal value of the comparison - increase of the speed-speed (1000 rpm).
Finally
nfK nf + nK; nrK pg n pK,
where nfK is the adjusted value of the comparison-increase of the step-speed;
nrK is the corrected value of the comparison short circuit the number of revolutions.
This variant of the method is explained in FIG. 10. It can be seen here that the command of the block 19 controlling the switching of the steps, using the speed signal inputted to the memory block 26, is determined by the comparison signal generating unit 27 the number of revolutions the correction value of the PC transmitted further to the number estimator 22 revolutions and in block 24 estimates of the number of revolutions. From this point on, the method proceeds as described.
 When toughening the conditions of a step increase, it was assumed that the elimination of situations of unreliable step increase is more likely than the toughening. However, it may happen that it will be redundant and impracticable. Here the driver can help. Having reset the fuel supply for a short time, it sets the mode in which the load signal s reliably drops below 6%. The system can also be provided with such an auxiliary program, so that the number of revolutions of the engine 1, rising above 2050 rpm, automatically removes the toughening of the conditions for increasing the level.
You can implement more simple variants of the proposed method. The block diagram in FIG. 11 represents one of the simplest options. Here, the switching of steps occurs under normal conditions as in the described variants. Memory unit 12 selects from diagram M (p is the moment value related to the feed signal
the accelerometer pedal position sensor 11 fuel, and the memory block 16 selects from the M (n) diagram the moment value related to the sensor 14 speed signal
revolutions. The load signal generating unit 21 generates, from these values of moments, the load signal s, and this signal by the load estimator 21, as well as the speed signal by the speed estimator 22, is monitored from the point of view of the stage switching condition and the block 19 the stage switching control signals a need for raising or lowering the lower stage, after which the stage switching control unit 19 transmits a corresponding command to the solenoid valve 17.
The simplification in comparison with the described embodiments of the method consists in the nature of the toughening of the conditions for increasing the stage. In block 22, the estimates of the number of revolutions, in addition to the normal value of nf, are the comparison-increase of the step-number
5 turns is also programmed to tighten the value of the nfs comparison-increase step-speed. Similarly, in block 24 of the rotational speed estimate, in addition to the normal value pg of the comparison –short closure — number of revolutions, the tightened value nrs of the comparison –short closure — number of revolutions is also memorized.
If the stage switching control unit 19 transmits coma through the amplifier 15 to the solenoid valves 17, switching to a reduced speed, it indicates to the speed evaluation unit 22 that it is necessary to monitor the speed signal from the sensor 14 in comparison with the tightened nfs value Comparison-increase steps-speed. Similarly, the rotational speed estimator 24 receives a command from the stage switching control unit 19 so that the closure condition of the friction clutch 4-toughened value nrs of the comparison-short circuit -number of revolutions existed further.
0 This toughening command of the control unit 19 by switching the stage is canceled by the next signal to increase the stage.
Toughened nfs compared to 5 not-increasing the step-speed and tightening the value of nrs comparison-short circuit-the number of revolutions can be equal to the previously described most rigid value nfMaxc comparison-raising the speed-speed number or the most rigid value pmax max-short circuits -frame-shortening-torsion speed or speed, speed or speed of the speed-speed.
In the block diagram (Fig. 12) it can be seen that the same simple variant of the method can be carried out if, based on the conditions for switching the stage, it is not the speed that is monitored, but the load value.
The load estimation unit 21 also provides a stricter comparison value sfs - increase of the load-step, and a load evaluation unit 22 also tightens the comparison value-short circuit load-load They can also be equal to the previously-tightened value srs comparison-increase the step-level load or toughened value sfnMH comparison-short circuit-load.
In order to use these toughened conditions, a command for lowering the stage is similarly formed by the block 19.
These two simplified versions of the method are to some extent similar to the previously applied solutions. But they are better because the basic switching conditions of the steps are analyzed to find the optimal load indicators for which the switching is performed.
A block diagram of a more complex embodiment of the method is shown in FIG. 18. In normal traffic situations, the case proceeds in accordance with the described process. The power supply unit 17 searches for the corresponding torque values from the sensor signal 12 of the accelerator pedal position from the M diagram (Ј), the memory block 18 searches for the corresponding torque values from the speed sensor signal 14 from the M diagram (n), and the block 21 generates a load signal s by the found values of the moments, which, using the load estimation unit 21, is compared with the value sf of the comparison-increase of the load-stage and with the value of sv of the comparison-decrease of the load-stage. The rotation speed estimator 22 compares the rotation speed signal with a signal expressing the value nf of the comparison-increase of the step-speed and the value nv of the comparison-decrease of the step-speed. According to the results of the comparison, the load evaluation unit 21 and the rotational speed evaluation unit 22 produce a corresponding signal, on the basis of which the step switching control unit 19 commands the solenoid valve 17 through the amplifier 15 to switch on the corresponding step.
Similarly, the load estimation unit 23 and the rotational speed estimation unit 24 give a signal to the clutch closure control unit 25. Based on this signal block 25
issues through the amplifier 1 b a command for closing or opening the coupling.
Before explaining the modification of the step switching, it is advisable to consider for what reasons, due to what change in the characteristics of the working state a shift to a lower step occurs.
Switching to a lower stage can occur in three situations, namely: with a normal decrease in speed, with overtaking and driving upward,
With normal deceleration, both the signal from the accelerometer and the engine 1 revolutions decrease, but here the decrease in the accelerometer signal is more intense (it can drop to zero), therefore the load signal s also decreases. A step decrease will also occur if the number of revolutions falls below the value of the nv comparison-lowering step. Having checked the change in characteristics, it can be seen that, having generated the change signal in the number of turns in the change in the number of revolutions, the change in load in the change in load and negative change in the characteristics reduction, we get a negative change in the number of turns and a change in the load in v .
When overtaking, both the accelerator signal and the number of revolutions increase, but as the number of revolutions may increase more slowly, the load signal s increases. A step decrease will follow as a result of an increase in the load signal s at an increased number of revolutions. Both the signal vn of the change in the number of revolutions and the signal vs of the change in load will be positive.
When moving on, the accelerator signal does not change or increases, the number of revolutions drops, so the load signal increases again. A step decrease will also occur here due to an increase in the load signal s. The signal vn of the change in speed will become negative, and the signal vs of the change in load becomes positive.
The state of characteristics before lowering the steps is given in the following table.
It can be seen that there are characteristics that, when analyzed in a pair, clearly indicate the need to lower the step, If the solutions applied in the same way to the toughening of conditions for increasing the step by one or two, you can choose the correct toughening based on the analysis of changes in known characteristics or without additional information.
This variant of the method is carried out as follows.
The signal s generated by block 21 is supplied to the load change estimator 28, where a change in load signal vs is generated from this change per unit time. It is fed to block 29, generating a comparison-load signal.
The speed signal from the sensor 14 is supplied to the speed change change estimator 30 and the speed change signal vn is generated from its change per unit time. This signal is applied to block 29, generating a compare-load signal.
In block 29, with the help of a command from the step control block 19 to switch on a lower stage, it is controlled what sign at that instant of such a step decrease the rotation speed signal vn and load change signal vs had. If both signals were negative, then a step decrease was preceded by a movement with a uniform speed or a usual deceleration. In this case, the unit 29, generating a comparison-load signal, leaves the stage increase conditions unchanged, i.e. A correction value is applied to the load evaluation unit 21 equal to zero. If both signals were positive, then a step decrease was preceded by a vigorous acceleration. In this case, block 29, generating a comparison-load signal, tightens the comparison value — increasing the step-load by a small correction value, and in block 21 the load estimation produces a signal expressing A constant amount of overtaking is comparison of load. Finally, if the signal vn of a change in the number of revolutions was negative, and the signal vs of a change in load is positive, then a decrease in the level is caused by an upward movement. On this basis, a block 29 generating a comparison-load signal tightens the step-load comparison-increase command by a more significant correction value, and in the load estimating unit 21 a signal is generated expressing a constant value of the lift-comparison-load movement.
For the implementation of the method, the conditions for raising the stage or their tightening are determined in the bus with the given parameters empirically in the following way.
The normal value of the comparison of the increase of the step-load is
25%, the value of overtaking-comparison-load 18%, the amount of movement on the rise-comparison-load b%. These values are generally equal to those defined in
described embodiments of the method. These options can be carried out without controlling the change in load. In this case, you need to determine how much the signal had the speed of the sensor 14 when switching to a lower level. If the rotational speed signal was lower than the nv value of the turn-down speed and the speed change signal was negative, then the unit 29 generating the comparison-load signal will evaluate it as a normal deceleration associated with the road situation and will not change the magnitude of the comparison — increase of the step-load, entered into the unit 21 of the evaluation of the load. If the speed signal is higher than before, and the speed change signal vn was positive, block 29 qualifies this as energetic acceleration and determines for load block 21
5 described overtaking load comparison,
If the speed signal had the same magnitude as the previous one, and the speed change signal vn was
0 negative, the unit will evaluate this as a lift motion and, for the load evaluation unit 21, determine the magnitude of the lift-comparison-load motion.
The described embodiments of the method can still be simplified if the differences between the usual deceleration and the energetic acceleration are not lost. In this case, the driver must actively supply fuel to draw out engine 1 for a longer period. Another simplification relates solely to friction clutch control and may be applied in any of the described embodiments. The simplest application is presented in the flowchart according to
5 of FIG. 14.
When describing the clutch control, it is indicated that the priority of raising the stage can be guaranteed by an appropriate choice of short-circuit conditions and switching to a higher level. This can be done as follows.
The sf value of the comparison — increase of the step-load and the value of the s-comparison — short circuit — of the load selected
5 in the same way, but the command of the step switching control unit 19 to switch to a higher step, a lock signal is given to the clutch closure control unit 25, if the conditions for the step increase are fulfilled
the clutch closure control unit 25 cannot issue a closure command.
In the previously described embodiments, the number of revolutions of the engine was controlled as a switching condition. It was indicated that a speed sensor 30 is integrated on the output shaft of the gearbox 2, the signal from which is also fed to the control unit 10. Instead of the engine speed 1, it is possible to monitor the speed of this shaft as a switching condition.
In the block diagram of FIG. 15, it can be seen that the number of revolutions of the engine 1 outputted by the sensor 14 is used only to determine the magnitude of the load s.
Since the speed signal of the sensor 30 expresses the true speed, not the engine speed 1, it is corrected in the step correction unit 31 to the proportion corresponding to the stage to be turned on, and the speed-speed-nseb signal is generated to the speed estimator 22, where it is compared with the same speeds used in the described embodiments. This option has the advantage that it also takes into account the effect of the hydrodynamic torque converter 3 This option can be combined with all other options.
In the described embodiments, the data, for example, was set in each case so that the gear shifting conditions in the presence of an engine, for example, with an automatic four-speed gearbox and planetary gear, could be sufficiently strongly deviated from each other, especially if the number of gears was not four. therefore, it is advisable to determine these conditions in each case empirically.
Special mention should be made of such variants of the method where it is necessary to control a synchronized manual gearbox.
Since in such vehicles it is not possible to solve the asynchronous ™ problem by overlapping stage switching, it is necessary to choose another option. Such an option is, for example, in monitoring the synchronism position. Since the engine speed, as well as the speed of the transmission drive shaft, is measured continuously, the synchronism position can be monitored, for example, by using clutch slip. The gearbox can also be protected by controlling the shift forks using pneumatic cylinders.
All variants of the method can be carried out on synchronized mechanical transmissions.
When creating a system for implementing the method, the absence of a hydrodynamic torque converter in the drive line and the need to control short-circuit conditions can create considerable relief.

权利要求:
Claims (7)
[1]
1. A method for shifting the steps of an automatic or automated mechanical synchronized gearbox of a car having a drive
5 line consisting of an internal combustion engine, kinematically connected through a hydrodynamic converter, configured to block the latter through a dry friction clutch with a stepped automatic transmission or connected through a dry clutch with a mechanical synchronized transmission, to which via a propeller shaft
5, a differential mechanism connected by at least one axle pair with wheels is connected, the auxiliary energy source being adapted to communicate by
0 electromagnetic control valves with control elements for engaging the clutch and automatic gearbox stages and fueling are carried out by moving the accelerator pedal, in which the rotational speed of the engine crankshaft or other rotating part is measured using a speed sensor the speed of the engine crankshaft, and the signal for switching on the gear is formed using an accelerator pedal position sensor, characterized in that In order to increase efficiency by determining the optimum gearshift point under any load, the relationship between the engine torque and accelerator pedal position and the relationship between engine torque and the number
0 engine revolutions and stored in the electronic memory unit, the signals proportional to the current frequency value of the engine crankshaft rotation and throttle opening degree are measured
5, by comparing the dependencies recorded in the memory unit, the values of the moments corresponding to the current theoretical values of the degree of throttle opening and the engine crankshaft rotation frequency are determined by
comparisons of moment values determine the load signal, the load signal is compared by means of a load estimator with signals of a constant magnitude comparison of stage increase and comparison of a step decrease, a signal of a rotation frequency is compared by means of a unit for estimating the number of revolutions of a step increase and comparison decreasing the step and when decreasing the value of the load signal is lower than the value of the signal of the magnitude of the comparison — raising the step and increasing the value of the signal of the number of revolutions The value of the speed increase comparison is formed by a speed switch unit to enable a higher gear and when the load signal increases above the signal value of the speed reduction comparison value and when the speed signal decreases below the speed reduction value signal, the speed switch downshift signal.
[2]
2. The method of claim 1, Tvt, which determines the relationship between the engine torque and the accelerator pedal position and the relationship between the engine torque and the engine speed and is stored in the electronic memory unit, the signals are proportional to the current frequency values of the moments corresponding to the current theoretical values of the degree of throttle opening are determined by comparison of the engine crankshaft and the throttle opening degree by comparison with the dependencies recorded in the memory unit. The crankshaft engine speeds and engine speeds, by comparing the torque values, determine the load signal, additionally determine the vehicle speed signal using a speed sensor by the number of revolutions of any structural part or by the average number of revolutions of any pair of structural parts of the drive line section of the car starting with the input shaft gearbox and wheel termination, mainly with the help of a stage adjustment unit modifying the gear according to the stage to be switched on, the load signal is compared by means of a load estimator with signals of a constant magnitude, a comparison of a step increase and a comparison of a step decrease, a speed signal is compared by a speed estimator with a signal expressing a constant value of a comparison — a step increase and
level decrease, and when the load signal decreases below the value that expresses the value of the level increase comparison, and when the speed signal increases
Above the value of the signal expressing the magnitude of the step increase comparison, by means of the step switching block, a switching signal to a higher step is generated and with an increase in the load signal
0 is higher than the value of the signal expressing the comparison value of the step decrease, and when the speed signal decreases below the signal expressing the value of the step decrease comparison by the control unit
5 by switching the steps form a switching signal to the lower stage.
[3]
3. The method according to claim 1 or 2, so that the load signal is additionally compared by means of an evaluation unit of the load signal with a comparison signal - the closing of the dry friction clutch of the hydrodynamic converter lock-up clutch, the frequency signal engine rotation at vehicle speed
5 is compared by means of an engine speed estimator with a signal expressing the magnitude of the comparison-coupling, and with an increase in the engine speed signal or vehicle speed higher than the signal value expressing the comparison-gating magnitude, and with a decrease in the load signal lower than the signal expressing the comparison value -clock by block
5 controls form a signal for closing the clutch of the hydrodynamic converter, and when the signal of the engine rotation speed or the vehicle speed is lower, decreases
A 0 signal expressing the magnitude of the comparison-clutch generates a signal for disengaging the clutch.
[4]
4. The method according to claims 1-3, characterized in that the speed signal is measured
[5]
5, the engine crankshaft or vehicle speed signal, inserts said signal into the memory unit, taking into account the signal of the step-switching control unit, by lowering the stage, then by means of the comparison-load signal-generating unit, reduce the signal expressing the comparison-elevation value, or / and a signal expressing the magnitude of the comparison of the short circuit to
5 The magnitude of the crankshaft speed or speed.
5 The method according to paragraphs. 1-3, characterized in that the engine crankshaft speed signal or the vehicle speed signal is measured
the signal is entered into the memory unit, taking into account the signal of the step control unit, to a step down, then by means of a block generating a comparison signal — the number of revolutions, increase the signal expressing the value of the step increase, and / or the signal expressing the value comparing the short circuit to a correction value depending on the magnitude of the crankshaft speed signal or the speed of movement,
[6]
6. Method according to paragraphs. 1-3, characterized in that using a step-down signal of the gear control unit increases by a certain amount a signal expressing the comparison value of a step increase and / or a signal expressing the comparison value of a short circuit or reduced by a certain value a signal expressing the magnitude of the comparison step, and / or possibly a signal expressing the magnitude of the comparison short circuit.
[7]
7. Method according to claim 1 or 2, from which it is so that by the speed signal, expressing the number of revolutions of the crankshaft of the engine, or by the speed signal at the number of revolutions in the unit for estimating the change in the number of revolutions, a signal is generated - the rotational speed and possibly the load signal in the load change assessment unit produce a load change signal and, by a command to decrease the step of the control unit for switching the steps, to instantaneous values for a negative turn signal change signal and revolutions expressing the number of revolutions of the engine crankshaft, having a value below the threshold value, or with a negative signal of a load change, produce a signal expressing a constant normal value of the comparison-load, and at a positive signal the change in the number of revolutions and at a signal of the number of revolutions expressing engine crankshaft and overspeed
Normal slowdown Below nv
Decreases
or when a load change signal is produced, a smaller one is produced compared to the previous signal, expressing a constant amount of movement on overtaking-load-load, while at a negative turn signal and a turn signal, expressing the number of turns of the engine crankshaft and exceeding a threshold value, or with a positive signal of a change in load, produce a very small signal expressing a constant amount of movement on the rise-comparison-load and the resulting Zoom signals input into the load estimation unit.
8 Method of PP, 1.2 or 7, and tl and h a torn, and so, through the command of the control unit switching steps to reduce the stage when the negative signal changes in the number of revolutions and when the signal is the number of revolutions expressing the number of revolutions of the engine crankshaft and above a threshold value, or with a positive signal of a change in load, a very small signal is produced, expressing a constant amount of movement on a lift-comparison-load, and in any other case a signal is expressed, expressing a constant normal value Neni -load.
9 Method one by one mz pp, 1-8, about t that insisting that the signal expressing the magnitude of the comparison — increasing the load-level, and the signal expressing the magnitude of the comparing-short circuit — of the load, are equal to each other load below the value of the signal expressing the magnitude of the comparison of the increase of the step-load, and increasing the value of the signal of the number of revolutions chosen for the unit for estimating the number of revolutions, higher than the value of the signal expressing the value of the comparison of increasing the degree of the speed of revolutions laziness simultaneously with a command to increase the control stage stage switching unit serves prohibition signal.
Movement on the rise Above nv
Is increasing
MM Nm
675 -I
0
Mini nm
675j4 1
Figz
Fig 2
f (J
2200 n f / PJ
Lg
L tf / p
2200
nf 1200
Lg 1yuo p0 900 nvzd70
M (n) ii NmJ 675
WOO FIG. 6
2200 n f / pj
12 g: -M I
I ..
.fig.7
-G
/ g
io
..-. h: „-., O
//
.
6
R
// g / 70
W.
Ql Mf
w
w
Z21ZSLI
Have
F
FIG. 15
Compiled by O. Bogoslovsky
Tehred M. Morgentl Corrector M. Demchik
1752182
I

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同族专利:

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公开号 | 公开日

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PL275261A1|1989-06-12|

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HU206654B|1992-12-28|

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CN1032524A|1989-04-26|

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DD275439A5|1990-01-24|

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EP0312801A1|1989-04-26|

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HUT48535A|1989-06-28|

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US4930374A|1990-06-05|

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法律状态:

优先权:

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申请号 | 申请日 | 专利标题

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HU874627A|HU206654B|1987-10-14|1987-10-14|Method for ratio switching of automatic or automatized mechanical synchronous gear box at motor vehicles|

---