DE102006001899A1 - Method for the adaption of boxed shifts of automatic transmission involves checking whether optimum synchronisation of first shift takes place assigning a cause for this to one or more parameters transition control and making a correction - Google Patents

Abstract

The method involves switching each one shift element on and each one shift element off and an intermediate shift is checked to see whether in the speed path in the area of the synchronisation point of the intermediate gear of the shift optimum synchronisation of the first shift has taken place and whether this synchronisation was so short that the box shift is perceived by the driver as a shift so that if synchronisation of the first shift has not taken place and/or the dwell time is longer or shorter than a predetermined value the cause for this is assigned to one or several parameters of the transmission control or assigned to a shift element or several shift elements involved in forming the transition in the intermediate stage so that an adaption can be undertaken to correct the switching on/off points of the shift elements.

Description

The The present invention relates to a method for adapting interleaved ones Circuits of an automatic transmission, according to the preamble of the claim 1.

The increasing demands on the functionality of automatic transmissions by the demand for more spontaneity, the ever-growing Number of gears to be shifted, the consumption-optimized design of the automatic transmission with larger driving proportions in the high corridors as well as the big one Number of executions downshifts when braking the vehicle to a standstill lead to that gears an automatic transmission increasingly faster and more frequently connected in series should be.

Around to perform a gearshift must the switching element to be switched first for the torque take-over prepared, i. filled become. Likewise also preparatory measures be taken at the switching off switching element, this being only after completion of the previous circuit is possible.

Usually becomes the preparatory filling process a switching element in a Schnellfüllphase and a Füllausgleichsphase divided: During the rapid filling phase, the switching element with oil filled, whereas in the filling compensation phase the Piston is applied with low load.

The known adaptation method for nested circuits are mostly aimed at adding the clutch adapt or the corresponding filling pressure of the individual couplings to detect. Likewise, the transmission capability of individual clutches or switching elements by suitable methods adapted. From the state of the art are also adaptation methods in which individual, up and down circuits are adapted. In these individual circuits usually the switching characteristics via sensors (e.g., speed sensors, torque sensors, pressure cells) and adapting the two clutches involved in the individual switching, the interaction of the clutches by the correction of the pressure control one or both involved in the circuit clutches influenced becomes.

From the DE 100 35 479 A1 the applicant is a method for improving the switching speed of automatic transmissions is known, in the context of which is required for the next circuit in the same direction to be switched or to be switched switching element during the first circuit is prepared or lowered to switching pressure, in such a way that upon reaching the synchronous speed of the first circuit, the immediate execution of the next circuit is made possible.

However, the known adaptation methods and also those in the DE 100 35 479 A1 described individual switching or clutch adaptation due to series variations often not sufficient. This is particularly the case when, due to the variation of the circuits in the direction of comfort and spontaneity, as for example in the context of DE 10 2004 010 269 A1 the Applicant is described, and also by appropriate intervening application variants, the variations can not be covered.

Of the The present invention is based on the object, a method for adapting nested circuits of an automatic transmission indicate which of the processes applied to a vehicle, also on the Vehicle (engine driveline, ...) and gearbox tolerances in the Series optimized well enough to maximize end user acceptance to achieve in the series.

Especially should the circuits or the clutches or the switching elements be adapted such that the mentioned interleaved circuits for the Drivers are perceived as a circuit; this shift quality and comfort over a Series as possible kept constant. In nested circuits switching over several Gears like that be designed that between the circuits no or one for the Driver not noticeable Dwell in the synchronization point between the circuits takes place.

One Another object of the invention is, over the life of the transmission the for the presentation of very sporty circuits necessary steep Speed gradients and the required connection and disconnection points optimally adjusted.

These The object is solved by the features of claim 1. Further Embodiments of the invention and variants will become apparent from the dependent claims.

Therefore is for a nested circuit in which each of the circuits in each case one switching element switched on and one switching element each is turned off, first proposed to check whether in the course of the speed in the area of the synchronization point of the intermediate of the nested Circuit provides optimal (i.e., not too early and not too late) synchronization the first circuit took place and whether this synchronization so short was that this nested circuit by the driver as a circuit is perceived.

To For this purpose, an evaluation of the turbine speed in relation to the output speed. In an inserted gear corresponds to the Output speed times the gear ratio the turbine speed. According to the invention is based on the evaluation of the turbine speeds in relation to the output speed at the ends of a defined interval around the synchronous speed of the intermediate passage determines the residence time in / around synchronous.

On this way becomes a "touchdown is detected on the synchronous speed of the intermediate passage. "Is the time in which the turbine speed in this window is too short (it exists the risk of missing the intermediate sync) or too long (es there is a risk of remaining in sync too long), then the cause is tried by suitable evaluation procedures therefor a clutch or a switching element or more of the the formation of the transition Attributing involved in the transition switching elements to this Switching elements subsequently to adapt.

in this connection comes the correction of the pressures the switching elements (gradient and level) and the correction of On and off times only at the next circuit to carry and is then re-evaluated and optimized.

moreover takes place according to the invention a speed gradient evaluation in the range synchronous of the intermediate passage. The speed gradient of the turbine speed must be in synchronous or flatten shortly before synchronous and run steeply after synchronous. If this happens after synchronous, then the synchronization took place the first circuit too late.

One too early Connecting the switching clutch of the first circuit would be short before synchronizing a much steeper speed gradient result, the likewise over a speed gradient evaluation can be assessed.

The The result of the speed gradient evaluation is the switching element involved or one or more of those involved in the formation of the intermediate transition Attributed switching elements, wherein in this operating range accordingly is adapted to the next Circuit to achieve an improvement.

As known from the prior art, the adaptation level based the deviation from the target value or in constant steps. In addition, the adaptation value can be changed globally or locally. This means that the adaptation value is in the entire operating range attacks or changes or only specifically at one point (e.g. temperature, pressure, torque, speed, and / or the type of shift, Etc. ...).

The The invention will be explained in more detail below by way of example with reference to the attached figures. Show it:

1 a representation of the curves of important parameters of a nested thrust reversing circuit, in each case a switching element is switched on each circuit and a switching element is turned off in each case;

2 a representation of an ideal sequence of a nested circuit with optimal acceleration curve on the example of a downshift;

3 a representation of a negative overlap of a nested circuit in which the dwell time in sync of the intermediate passage for the driver is noticeable;

4 a representation of a nested circuit in which the intermediate synchronization is missed;

5 a representation of a nested circuit in which the connection of the synchronizer clutch, ie the engaging clutch of the first circuit takes place too early;

6 a representation of the evaluation of in 3 shown circuit as a function of time in / around synchronous and the course of the speed gradient of the turbine speed;

7 a representation of the evaluation of in 4 shown circuit as a function of time in / around synchronous and the course of the speed gradient of the turbine speed;

8th a representation of the evaluation of in 5 shown circuit as a function of time in / around synchronous and the course of the speed gradient of the turbine speed; and

9 a schematic representation of the most important steps of the method according to the invention.

According to 1 When an exemplary push-down circuit is initiated, the preparation of the switching element P_KZU (1) to be switched starts with the fast filling of the switching element. The switching off switching element P_KAB (1) starts with the switching phase. The prepared to be switched switching element P_VKZU (1) remains at minimum pressure. The prepared switching off switching element P_VKAB (1) is set to a defined pressure. This time will be in the 1 denoted by A.

Subsequently (point B in 1 ) switches the switching element P_KZU (1) to be switched within the preparation phase in the Füllausgleichszeit. The states of the other processes do not change.

While the states of the switching elements P_KZU (1), P_KAB (1) associated with this circuit and the prepared switching off switching element P_VKAB (1) do not change, the preparation phase of the switching element P_VKZU (1) to be prepared for the next circuit with the fast filling begins according to the invention, like in the 1 shown at time C. The starting point of P_VKZU (1) can be applied and can be time- or event-controlled; an example of the timing is the time T_VKZUVxy.

requirement for the The beginning of the preparation phase is the existence of certain conditions, such as. a delay time after fast filling of the switching element P_KZU (1) to be switched. This means that the timing of the start of the preparation phase by circuit-specific Application parameters can be influenced within wide limits.

Then changes the switching element P_KZU (1) to be switched from the preparation phase in the switching phase, the phases of the other switching elements unchanged stay. This is caused by a pressure increase at time D.

Then you go According to the invention to be prepared to be switched switching element P_VFZU (1) within the preparation phase in a phase of constant pressure over. This phase is achieved by lowering the pressure to the level of the leveling pressure (Point E) initiated.

In one next Step is at a defined subsequent time F, the transition phase of the prepared switching-off switching element P_VKAB (1) started: The transition For example, by the time to the switching phase of the following Circuit can be defined. The states of the other switching elements change Not. The timing of the transition is in wide by circuit-specific application parameters Limits influenced.

The prepared switching element P_VKZU (1) to be switched leaves the filling compensation of the preparation phase at this defined point (eg by a speed reservation before synchronous) and enters the switching phase, the transition preferably being ramp-shaped. The states of the other switching elements remain unchanged. This phase corresponds to point G in 1 ,

Between the expiration of the prepared switching-off switching element P_VKAB (1) (eg background sequence) and the first switching element P_KZU (1) to be switched - point H in FIG 1 The transition takes place, whereby the change between the background sequence and the active sequence is carried out. The switching element P_VKZU (1) prepared in the first circuit becomes the switching element P_KZU (2) of the following circuit to be switched. The first switching off switching element P_KAB (1) is switched off.

The prepared switching elements P_VKZU (1) and P_VKAB (1) of the first circuit are now (point I) the active switching elements P_KZU (2) and P_KAB (2) of this circuit, while the necessary for the next circuit switching elements - as already explained - prepared become P_VKZU (2) and P_VKAB (2). This is done with the switching element P_VKZU (2) necessary for the connection to a point defined, for example, by a delay time after the transition condition (see point J in FIG 1 ) carried out.

In 2 By way of example, a nested downshift with optimum acceleration profile is shown. Here, curve A 'corresponds to the curve of the turbine speed, curve B' the course of the synchronous speed of the originally gear, curve C 'the course of the synchronous speed of the intermediate gear and curve D' the course of the synchronous speed of the target gear. Curve E 'shows the course of the acceleration or the drive torque, wherein the time course of the accelerator pedal position is represented by curve F'. These designations of the gradients also apply to the 3 . 4 . 5 . 6 . 7 and 8th , Due to the substantially linear course of the turbine speed about the synchronization point of the intermediate passage, the in 2 shown nested circuit perceived by the driver as a circuit.

An example of a non-optimized circuit is the subject of 3 , In the circuit shown, the dwell time t in synchronism of the intermediate passage is felt by the driver, so that the interleaved circuit can not be perceived by the driver as a circuit; disadvantageously, the disconnecting clutch of the second circuit is switched off too late.

In practice, the situation often occurs in which the dwell time in sync of the intermediate course is very short, or in which the intermediate synchronization is missed; this situation is based on 4 illustrated. In this case, the engaging clutch of the intermediate circuit is added too late tet and the intermediate synchronization missed. Further non-optimal circuit characteristics can result, for example, from the fact that the switching clutch of the first circuit is switched on too early, that the disconnecting clutch of the first circuit is switched off too early, or that the disconnecting clutch of the first circuit is switched off too late. In addition, a combination of several unfavorable tolerance positions or coupling behavior is possible; For example, the disconnecting clutch of the second circuit can be switched off too late and the switch-on clutch of the first circuit can be switched on too early.

In 5 the situation is shown in which the connection of the synchronizer clutch, ie the engaging clutch of the intermediate circuit, too early (ie before synchronous) takes place; this time is denoted by t '. How out 5 As can be seen, this results in a disadvantageous manner a noticeable kink in the course E 'of the acceleration or the output torque.

6 illustrates the procedure of the invention for evaluating a circuit as a function of dwell in / around synchronous and the speed gradient of the turbine speed based on the evaluation of in 3 shown circuit.

In an engaged gear corresponds to the output speed times the gear ratio the turbine speed. According to the invention is based on the evaluation of the turbine speed in relation to the output speed n_ab at the ends n_1, n_2 of a defined interval (n_1, n_2) about the synchronous speed of the intermediate gear, which is represented by n_ab.i_gang is given, determines the residence time in / synchronous.

In 6 the individual intervals delta_na and delta_ne are also plotted, which correspond to the interval between n_1 and synchronous speed or between synchronous speed and n_2. If the time in which the turbine speed is in this window or interval (n_1, n_2) is too short or shorter than a predetermined value, there is the danger that the intermediate synchronization will be missed; On the other hand, if this time is longer than a predetermined value, there is a danger that the synchronization will be left too long, which is noticeable to the driver. At the in 6 In the example shown, the time t is too long to synchronize, so that it is disadvantageously felt by the driver.

A further criterion of the evaluation of a circuit according to the invention is a speed gradient evaluation of the turbine speed in the range synchronous to the intermediate gear. The speed gradient must flatten in synchronous or shortly before synchronous and run steeply again after synchronous. If this happens after synchronizing, then the synchronization of the first circuit was too late. This situation is based on 7 illustrated.

At the in 7 As shown in the example, the engaging clutch of the first circuit (intermediate circuit) was switched too late, which is detected by the belated with respect to the time of reaching the synchronous speed flattening of the speed gradient of the turbine speed. In the example shown, moreover, the dwell time t is very short around synchronization, so that there is a need for adaptation with regard to the connection time of the switching clutch of the first circuit.

In 8th is the evaluation of in 5 shown circuit as a function of time in / around synchronous and the course of the speed gradient of the turbine speed. In this figure too, the individual intervals delta_na and delta_ne are plotted, which correspond to the interval between n_1 and synchronous speed or between synchronous speed and n_2. The speed gradient runs in this case just before synchronous steep and flat in synchronous, in contrast to an optimal course, in which the speed gradient flattened just before synchronous. In this case, there is a need for adaptation, because the engaging clutch transmits the moment too early.

Upon detection of an adaptation requirement on the basis of the evaluation of the deviation from an optimal course, the cause of this is attributed to one or more variables of the transition control or attributed to a clutch or more of the clutches involved in the formation of the transition in the transition to an adaptation via a correction the clutch pressures (gradient and / or level) or to perform a correction of the switching on and off times of the switching elements. If an assignment of the cause of the deviation from the optimal course is not possible, no adaptation is carried out. This procedure is in 9 shown schematically.

When nested circuits can according to the invention Single circuits (e.g., 5-4 with 4-3 or 3-4 with 4-5) or multiple circuits (e.g., 6-4 with 4-3 or 6-5 with 5-3, 6-2 with 2-1, 6-4 with 4-2, 2-4 with 4-5).

P_KZU (1)

to switching switching element

P_KAB (1)

abschaltendes switching element

P_VKZU (1)

prepared switching element to be switched

P_VKAB (1)

prepared switching off switching element

T_VKZUVxy

starting point from P_VKZU (1)

P_KZU (2)

to shading switching element of the following circuit

n_t

Turbine speed

i_gang

gear ratio

n_ab

Output speed

(N_1, n_2)

interval about the synchronous speed of the intermediate gear

delta_na

interval between n_1 and synchronous speed

delta_ne

interval between synchronous speed and n_2

A '

course the turbine speed

B '

course the synchronous speed of the original switched Ganges

C '

course the synchronous speed of the intermediate gear

D '

course the synchronous speed of the target gear

e '

course the acceleration or the drive torque

F '

course the accelerator pedal position

Claims (4)

A method for adapting nested circuits of an automatic transmission, wherein in each of these circuits in each case one switching element is switched on and one switching element is switched off, characterized in that the intermediate circuit is checked to see whether in the course of the rotational speed in the region of the synchronization point of the interlaced nested circuit optimal Synchronization of the first circuit has taken place and whether this synchronization was so short that this interleaved circuit is perceived by the driver as a circuit, wherein in the event that the synchronization of the first circuit has not taken place or not run optimally and / or Dwell time in / to synchronous the intermediate passage is longer or shorter than a respective predetermined value, the cause associated with one or more variables of the transition control or a switching element or more of the formation of the transition in the intermediate passage attributed to involved switching elements, to subsequently perform an adaptation via a correction of the switching element pressures (gradient and / or level) or a correction of the switching on and off times of the switching elements. Method for adapting interleaved circuits An automatic transmission according to claim 1, characterized that the residence time in / around synchronous based on the evaluation of the turbine speed in terms of output speed at the ends of a defined Interval (n_1, n_2) about the synchronous speed of the intermediate gear, those through n_ab · i_gang is given, is determined. Method for adapting interleaved circuits An automatic transmission according to claim 1 or 2, characterized that the course of the speed gradient of the turbine speed in Range of the intermediate gear is evaluated, whereby it is checked whether the speed gradient flattened in synchronous or shortly before synchronous and after synchronous again runs steeply, and if this process after synchronous, too late synchronization of the first Circuit is detected, and being detected in the event that is that before synchronizing a significant speed gradient increase done, one too early Connection of the switching clutch is detected and an adaptation carried out will be too early a transfer the moment to avoid from the activating coupling. Method for adapting interleaved circuits An automatic transmission according to claim 1, 2 or 3, characterized that the adaptation height based on the deviation from the target value or in constant steps takes place, wherein the adaptation value in the entire operating range or in one point of the operating range as a function of temperature, pressure, Moment, speed, and / or the shift engages or is changed.