DE19524412A1 - Automobile clutch closure control - uses processor controlling axial displacement of at least one clutch element to obtain required transfer torque characteristic - Google Patents

Abstract

The clutch closure control regulates the clutch closure for reducing the difference between the revs of the clutch elements on the input and output sides, with the axial position of at least one of the clutch elements being adjustable. The axial adjustment of the latter clutch element is controlled by a processor, for providing regulation of the clutch transfer torque (Mdk) in dependence on a required transfer torque characteristic for the detected drive revs.

Description

The invention relates to a control device for Regulation of the closing process of a disconnect clutch and / or to regulate the opening process of a clutch for Motor vehicles according to the preamble of the claims 1, 2 and 3.

Such a control device for automatic coupling Actuation is for example from DE 40 26 659 A1 known. In this known control device using sensors both the drive speed, d. H. the Speed of the drive or motor-side clutch element mentes, as well as the output speed, d. H. the speed of the output or transmission-side coupling element detected. By means of a clutch control, at least a coupling element for opening or closing the partition clutch axially actuated. Especially during a gang circuit in the transmission, the disconnect clutch is open where by turning the drive after a new gear number and the output speed of the coupling elements un are different. In the known control device, which is preferably effective in the case of a downshift, is used to adjust the speed of the coupling elements drive speed, e.g. B. by a throttle valve in internal combustion engines as a drive, so controlled that the drive speed just before closing the Separating clutch is always higher than the output speed. This will cause the separating clutch to close at the moment the drive-side coupling element and thus the An  drove himself braked. With this known tax Direction therefore remains at the time of completion a speed difference when the separating clutch is closed between the output speed and the input speed, which leads to a noticeable acceleration shock.

It is an object of the invention to provide a control device gangs mentioned to improve such that during the Closing process and / or during the opening process ner at least partially open or closed Isolating clutch maximum comfort is achieved.

This task is characterized by the characteristics of the Claims 1, 2 and 3 solved.

According to claim 1, the means according to the invention for the axial adjustment of a coupling element a Re Chen unit by which a regulation of the clutch transmission torque depending on a target course the drive speed is feasible.

The invention is based on the idea that optimal Comfort when closing and / or opening the Separating clutch by regulating the clutch moment is reached. One would be optimal for this Regulation depending on a target course of the coupler transmission torque even in comparison with the mo mental actual course of the clutch transmission torque. There however, the measurement of the clutch transmission torque Creation of an actual course too complex and cost in is intensive, a regulation according to the invention is dependent of a size that is easy to grasp, namely the Speed of the drive-side coupling element, which at for example, is equal to the engine speed, carried out. The advantage of a regulation depending of this drive speed is the simple physi correlation between a torque and a  Speed change taking into account the inertia mo ment of the rotating masses. It is from the general Formula out:

M = 2π _* J _* dn / dt,

where J is the moment of inertia of rotating masses.

The drive speed depends primarily on one System "drive" acting total torque, which is from a drive-side torque in the form of a supplied energy minus the clutch transmission moments in the form of an extracted energy. However, the drive torque is preferred in the form of an input energy for simplification at least temporarily at a predetermined value held while regulating the clutch transmission moments solely depending on the course of the target drive speed is made. This will make one Simple control strategy without additional hardware expenditure for a comfortable closing and / or opening operation of a separating clutch.

According to claim 2, the means according to the invention for the axial adjustment of a coupling element a Re Chen unit through which a control or regulation of the clutch transmission torque can be carried out in such a way that the course of the drive speed at the beginning of Closing process, preferably for a predetermined time, not through a positive contribution from a drive side torque is affected.

In particular, for a predetermined time, preferably also by reaching a predetermined drive rotation value can be defined, the drive egg torque in the form of energy supplied only kept constant but also so low that it does not NEN contribution to influencing the drive speed ver runs. This is preferably the drive side  Torque constant on one with respect to the clutch transmission torque held negative value, the usual anyway when changing gears due to moments reduction is specified. Thus, according to the invention e.g. B. during a closing process of the disconnect clutch the speed difference between the clutch on the output side tion element and the drive-side coupling element for the most part exclusively through the corresponding one position of the clutch transmission torque. This will especially at the beginning of the closing process achieves a harmonic acceleration curve that at simultaneous regulation or control of the clutch bearing torque and the drive torque due to the complex interaction of the coupling, the Ge drive and the drive is hardly accessible. Hereby becomes a comfort improvement in a particularly simple manner tion reached.

According to claim 3, means are also according to the invention to control or regulate the drive torque ment available. It is a control or regulation of the Clutch transmission torque and / or the drive side gen torque made such that the clutch transmission torque less than the drive-side rotation moment is when the curve of the drive speed increases gen and the clutch transmission torque is greater than the drive side torque is when the course of the Drive speed should drop.

This invention is based on the idea that, for. B. the Closing process of the disconnect clutch at particularly high An demands for comfort at the expense of a night swell the drive speed during the dismantling of the Speed difference can be made. Here will assumed that for a vehicle occupant a slow closing of the clutch of acceleration dependent comfort can be increased significantly  rend a short slight increase in drive speed only causes little acoustic interference.

According to the invention, there is therefore a change in the sign approved of the gradient in the drive speed curve sen to match a corresponding control or Regulation of the clutch transmission torque and / or the torque on the drive side, preferably dependent speed of a predetermined target course of the drive rotation number to make. This will make it particularly easy Optimal comfort during the closing process and / or during the opening process of a separating clutch reached.

In addition, it is pointed out that the invention as well as any combinations of objects Claims 1, 2 and 3 includes. Thus advantageous Wei terbildung the inventions the combinations of counterparts states of claims 1 and 2, 1 and 3, 2 and 3, 1 and 3 or 1, 2 and 3.

Exemplary embodiments of the invention are shown in the drawing shown. It shows

Fig. 1 performs a control device according to the invention, the operating speed a control of the clutch transmission torque in dependence on a set curve of the at the beginning of the closing process without any positive contribution of a drive-side torque,

Fig. 2 shows a control device according to the invention, which carries out a regulation to extend the closing process, in which a reverberation of the drive speed is permitted and

Fig. 3 shows a control device according to the invention, which performs a regulation of the clutch transmission torque as a function of a desired profile of the drive speed and / or of a desired opening profile of the clutch during an opening operation of the clutch.

The control device according to the invention is shown in Figures 1 and 2 for the example of an upshift..:
In Fig. 1, the torque M _{d is} plotted on the ordinate and the time t is plotted on the abscissa. On the one hand, the course of the clutch transmission torque M _dK and on the other hand the course of the drive-side torque M _dMot are shown. The drive speed n is plotted over time in the middle diagram and the state of the clutch over time in the lower diagram.

At the time t₀ = 0, the actual shifting process in the sense of engaging a new gear has already taken place, so that the closing process of the opened clutch can begin. At the beginning of the closing process, up to the predetermined point in time t _x, only the clutch _{transmission torque} M _{dK is regulated} as a function of the desired course of the drive speed n, as shown in the middle diagram. The drive-side _torque M _dMot is kept constant from the time t₀ to the time t _x, the negative torque _value M _d2 , which was already set during the gear change. The drive-side torque M _dMot with the constant value M _d2 makes no positive contribution to the course of the drive _{speed n} up to the time t _x . The time period t _x - t₀ is defined such that a drive speed value n₂ + n _{offset is} reached at the time t _x . The drive speed value n ₂ corresponds to the new drive speed from the transmission-side clutch element after an upshift. To reduce the speed difference between the output-side and the drive-side coupling element, the drive speed must be reduced by the value n₂ - n₁ in this case.

The value of the drive speed difference n _offset corresponds to a speed drop that takes place due to the clutch engagement between the times t _x and t 1. This value n _offset can also be calculated and adapted depending on the newly selected gear, the acceleration or the driving resistance. From the time t₀ to t _x , a clutch _{transmission torque} M _dK necessary to achieve this target profile is calculated according to the target profile of the drive speed n from the value n₁ to the value n₂ + n _offset according to the following formula:

M _d = + M _dMot - M _dK = 2πJ _* dn / dt,

where M _{dMot has} a constant value of M _d2 .

To regulate the clutch _{transmission torque} M _dK , this formula is broken down into the drive speed n in order to determine the actual course of the drive speed n resulting from the current clutch _{transmission torque} M _dK .

To simplify 1 a ramp-shaped Ver running of the clutch transmission torque M _dK and a pre-time period is passed in Fig. Dt, z. B. corresponds to the sampling cycle time of the computer program. With this simplification, the following formulas result for the time t _x , for the clutch _{transmission torque} M _dK (t-dt / 2) currently to be set and for the resulting drive _speed n (t) at the time t:

The clutch _{transmission torque} M _dK to be set _{corresponds in} each case to an axial adjustment position of a clutch _element , between a completely open (“open”) and a completely closed (“closed”) coupling. If at the time t _x approximately the speed value n₂ + n _{offset is} reached, a continuous increase in the drive-side torque M _{dMot begins} up to the point in time t₁ at which the drive-side torque M _dMot the value of the present clutch transmission torque M _dK = M has reached _d1 . Preferably, the current clutch _{transmission torque} M _{dK is kept} constant at the value M _d1 in the period t ₁ - t _x , ie the position of the clutch is held in the same time period at the position set at time t _x . The value M _d1 is selected, for example, in internal combustion engines as drive in such a way that it corresponds to a minimum possible drive-side torque adjustment by ignition angle late.

A possible further course after the time t 1 is shown in the embodiment of FIG. 2.

In Fig. 1 of the clutch transmission torque M _dK, the n antriebsseiti gen torque M _dMot, the drive speed and the clutch position are shown with thinner lines still possible courses, for example, then arise when it is requested during the closing operation from Fah rer increased power, e.g. B. in the form of an increase in the accelerator pedal angle. In this case, who took the same measures as in the example corresponding to the thick lines, with the exception that all gradients have increased gradients. From this it can be seen that both requirements for comfort and requirements for sportiness can be met.

In Fig. 2 all courses from the time t₀ to the time t₁ correspond to the courses in Fig. 1 at the time points t₀ or t₀ 'to the time t₁ or t₁'. At the time t ₁ in the lower diagram in both Fig. 1 and Fig. 2 it can be seen that the clutch is still far from the fully closed state. For example, it would be possible to close the clutch as quickly as possible with a steep gradient of the clutch _torque M _dK . In Fig. 2, however, a comfort-optimized course is shown, in which the closing process is to be extended after the speed difference has been reduced in order to close the clutch as softly as possible. For this purpose, a reverberation in the course of the drive speed n up to a maximum permissible drive speed n _{max is} allowed. From the time t 1 to the time t 3, the value n _{max should increase} again after the course of the drive speed n. During this increase phase in the drive speed curve, the clutch _{transmission torque} M _{dK is} kept lower than the drive-side _torque M _dMot . Preferably, a change in the slope of the profile of the clutch _{transmission torque} M _{dK is} made at the turning point at time _{t 2} in accordance with the change in the gradient in the drive _{speed profile} . At the time t₃, the target curve of the drive speed n has a gradient with the value 0 at the maximum permissible drive speed value n _max . At this time point t₃ are the clutch transmission torque M _dK and the drive-side torque M _dMot equal value _d4 M the torques.

Between the time t₃ and t₅ the course of the drive speed n should drop. In this time range, _{according to the invention,} the clutch transmission torque M _{dK is} set greater than the drive-side torque M _dMot . At the time t in, the drive speed value n₂ + n _offset is approximately reached again, so that the clutch is completely closed between the period t₆ - t₅. From the time t₆, at which the clutch is completely closed again, the value of the clutch transmission torque M _{dK is} equal to the value of the drive-side torque M _dMot .

In the lower diagram of FIGS. 1 and 2, the proportional course of the clutch position corresponding to the set clutch _transmission torque M _{dK is} evident.

In addition, it is pointed out that in the Ausfü Examples only ramp-shaped curve ver runs are shown, however, any courses continuous type are conceivable. Ramp-shaped courses are, however, particularly advantageous to use in computing dents for the torque values and the drive speed value to be able to accept simplifications.

In addition, two possible exceptional cases at time t _{x are} pointed out: At time t _x , a drive speed value n can be achieved due to various influences, which is either between the value n₂ and the value n₂ + n _offset or even below the value n₂. In the latter case, the drive side torque is preferably first raised to at least the instantaneous value of the clutch transmission torque M _dK . Thereupon and also in the first case, an increase in the drive speed n is achieved in that the drive-side torque M _dMot , even with increasing clutch transmission torque, is kept greater than the clutch transmission torque. The further procedure speaks again the embodiment of FIG. 2, accordingly, a desired increase or a desired th of the drive speed curve.

Fig. 3 shows an opening process of the clutch. The diagram above shows the course of the clutch transmission torque M _dK and the drive-side torque M _dMot . The middle diagram shows the drive speed n over time t and the lower diagram shows the state of the clutch over time t.

At time t₀ = 0 there is a switching command to open the clutch, e.g. B. in the form of a gear change request, so that the opening process of the closed clutch ("to") begins. At the beginning of the opening process, for example by retarding the ignition angle or by blanking the cylinder, the drive-side torque M _{dMot is reduced} . Up to time A, the drive-side torque M _{dMot is} below the clutch transmission torque M _dK and is reduced as much as possible. Up to the time A, at which the clutch About tragungsmoment M _dK has been transferred to the value of the drive-side torque M _dMot, even a slight opening of the clutch takes place, which in particular sondere is load dependent.

Between time A and time B, which can be defined by a predetermined time t1, the drive-side torque M _{dMot is} above the clutch transmission torque M _dK and is kept constant at the value reached at time A. This increases the input speed n compared to the gearbox input speed n _k on the output side. Kinetic energy is built up on the drive side in order to be able to dissipate it again between times B and C to optimize comfort.

The course of the clutch _{transmission torque} M _dK is regulated between times A and B depending on a desired course of the drive _speed n or controlled depending on a predetermined opening course of the clutch. Preferably, the course of the clutch _{transmission torque} M _{dK is} controlled and / or regulated in such a way that a predetermined opening degree K _is to be achieved at time B and / or the maximum of the course of the drive speed n is reached. Although the drive-side torque M _dMot is not further reduced between times A and B, a very flat profile of the clutch transmission torque M _dK is possible, thereby op timaler comfort is achieved.

From time B, the clutch opening process and the course of the drive _speed n are no longer influenced by a positive contribution of the drive-side torque M _dMot . The kinetic energy built up on the drive side between times A and B is reduced again. As a result, an even flatter course of the clutch transmission torque M _{dK is} possible between times B and C, which results in a very slow and comfortable transition to the fully open state of the clutch (“on”).

Between times B and C, the drive-side torque M _{dMot is} again below the clutch transmission torque M _dK , as a result of which the profile of the drive _speed n drops. As a result, the drive speed n = n _{mot can} again be brought up to the gearbox input speed n _k on the output side.

With these embodiments is simple and ko cost-effective way to optimize comfort with respect to egg Nes closing process and / or an opening process Separation clutch created for motor vehicles.

Claims (3)

1. Control device for controlling the closing operation of a separating clutch for motor vehicles for the automatic reduction of the speed difference between the output-side coupling element and the driving-side coupling element and / or for regulating the opening process of a separating clutch with means for detecting the drive speed and with means for axial adjustment at least egg _Nes coupling _{element of the separating} clutch, characterized in that the means for axial adjustment have a computing unit, by means of which the clutch _{transmission torque} (M _dK ) can be _controlled as a function of a set course of the drive speed (n). 2. Control device for regulating the closing process of a separating clutch for motor vehicles for automatically reducing the speed difference between the output-side coupling element and the driving-side coupling element and / or for regulating the opening process of a separating clutch with means for detecting the drive speed and with means for axial adjustment at least egg Nes coupling element of the separating clutch, characterized in that the means for axial adjustment have a computing unit through which a control or regulation of the clutch transmission torque (M _dK ) can be carried out in such a way that the course of the drive _speed (s) at the start of the closing process (t₀ to t _x ) is not influenced by a positive contribution of a drive-side torque (M _dMot ). 3. Control device for regulating the closing process of a separating clutch for motor vehicles for automatically reducing the speed difference between the output-side coupling element and the driving-side coupling element and / or for regulating the opening process of a separating clutch with means for detecting the drive speed and with means for axially adjusting at least egg Nes coupling element of the separating clutch, characterized in that means for controlling or regulating the drive-side torque (M _dMot ) are present and that the means for axial adjustment and the means for controlling or regulating the drive-side torque have a re computing unit through which a control or regulation of the clutch transmission torque (M _dK) and / or of the drive-side torque (M _dMot) is such carried out that the Kupp lung transmission torque (M _dK) is less than the drive-side torque (M _dMot) when the curve of the A drive speed (s) should increase, and vice versa.