DE10163402A1 - Motor vehicle with multiple clutch and multi-gear gearbox, has controller for detecting increased probability of down shift to lower destination gear and engaging a suitable gear - Google Patents

Abstract

The vehicle has a drive train with a drive unit, a gearbox with two input shafts, a multi clutch device and a controller that is designed to detect the increased probability of a down shift to a lower destination gear relative to the initial gear on the basis of setting a flashing signal or/and on the basis of a steering actuation exceeding a minimum actuation and to engage a suitable potential destination gear with an actuation arrangement. The vehicle has a drive train with a drive unit (12), a gearbox (18) with two input shafts (20,22), a multi clutch device (24) and a controller (36) that is designed to detect the increased probability of a down shift to a lower destination gear relative to the initial gear on the basis of setting a flashing signal or/and on the basis of a steering actuation exceeding a minimum actuation and to engage a suitable potential destination gear with an actuation arrangement (56). AN Independent claim is also included for the following: a controller for a motor vehicle.

Description

The invention relates to a motor vehicle with a multiple clutch Multi-speed transmission, in particular double clutch multi-speed transmission. More specifically, the invention relates to a motor vehicle with a Drivetrain comprising a drive unit, a transmission with a first and a second transmission input shaft and a multiple clutch device, in particular double clutch device, with one of the first Transmission input shaft associated first clutch assembly and one of the second transmission input shaft assigned or associated second Coupling arrangement for torque transmission between the Has drive unit and the transmission, wherein a control device is provided, by means of which the gearbox or associated actuator system in association with a respective one of the first and the second transmission input shaft transmission gears can be engaged and disengaged and by means of an associated or associated with the coupling device, if necessary, the clutch arrangements can be actuated in this integrated actuator system are, the control device being designed for preparation an overlap circuit in which in association with one currently load transmitting the transmission input shafts an output gear and in Assignment to a currently not load-transferring Transmission input shafts a target gear are engaged at the same time and then that of the previously load-transmitting transmission input shaft associated clutch assembly in terms of disengagement and that of those who have not yet transferred the load Gearbox input shaft assigned clutch arrangement in the sense of a Is engaged based on input data to determine the likely target gear and assign it to the currently not load-transmitting transmission input shaft as a potential target gear in addition to one in association with the current load transfer Gearbox input shaft inserted, the output gear to be prepared Overlap circuit representing gear (hereinafter referred to as Exit gear designated).

Such a motor vehicle is implicitly disclosed in DE 199 37 716 C1. This patent specifically suggests one associated with the transmission electronic control device as "gait prognostic and Gear selection device "by means of which current operating data can be predicted before the request for a gear change, whether in In the future a gear change is likely to be required and which one future gear will likely be the control device then when such a future gear change seems likely, this by means of the gear actuator to prepare the Overlap circuit inserted. Depending on the operating data for the Gear forecasting and gear selection function of the control device exists according to the explanations in the patent for the control device Possibility for the following decisions: No statement possible or high probability of an upshift (from a lower one) Exit gear into a higher target gear) or high probability for a downshift (from a higher output gear to a lower target gear). It should be noted that the proposal of the patent compared to other prior art, at least in an overall view (see DE 40 31 851 A1, EP 0 827 861 A2, DE-PS 923 402, DE 197 51 456 A1 and trade journal "Automotive Engineering, Feb. 1983, p. 80-82) contains little new.

The patent specification does not contain any details on which Way the operational data is evaluated and how from the different, in the operating data mentioned the patent Probabilities are determined.

Even if the skilled person has yet to complete the teaching of DE 199 37 716 C1 is left to the proposal of Intent underlying patent specification makes sense. At a It is a multiple clutch transmission, in particular a double clutch transmission namely desirable for various reasons, the actions of one "Anticipate" the driver and, based on this knowledge, the next one The driver has already selected the desired gear. Then it can immediately upon the driver issuing a shift command (for example manually by operating a gear selector lever or Shift paddles or by depressing the accelerator pedal to initiate such a process called kick-down circuit) without delay Overlap circuit are triggered. Especially with kick-down circuits the driver expects a spontaneous reaction from the vehicle, which is only can be realized when the next lower gear is already engaged.

Spontaneous acceleration requests from the driver, which one Downshift necessary, z. B. Situations where the driver for a long time at a relatively constant speed behind you slow moving vehicle and a favorable traffic situation wants to use to overtake.

To that extent, the mentioned patent specification DE 199 37 716 C1 points to the right direction, but there are still no proposals, such as the "right" Target gear actually predicted based on the input data shall be.

As far as the preparation of an overlap circuit for Going to a lower gear, you might think prefers to use the next lower gear as a potential target gear, to react spontaneously to downshift commands.

Such "provision" of a lower gear is not always the case be the right choice, because then an "unexpected" coming Upshift command first selected the gear and the desired higher gear needs to be engaged, which becomes clear for the driver noticeable inertia of the system.

In addition, when a lower gear is provided, the transmission side half of the clutch assembly in question and all assigned Wheels and shafts of the gearbox up to the additionally inserted lower one Gear step relative to the gear step of the closed (load-transmitting) Coupling arrangement faster and must therefore be used by everyone Acceleration process co-accelerated or slowed down, what from Energy efficiency is disadvantageous. Furthermore, the speed of the inserted gear is monitored to prevent damage and if a limit speed is exceeded, the gear engaged again be interpreted. If the limit time is exceeded again, the potential (lower) target gear can be reinserted to a possible to react spontaneously to a downshift command.

In contrast, the invention proposes that the control device for this is designed to increase the likelihood of a downshift based on a lower target gear compared to the exit gear the setting of a blinking signal and / or on the basis of a one To recognize minimum actuation exceeding steering actuation and one corresponding gear as a potential target gear by means of the actuator system appeal.

The invention is based on one aspect of the idea that the Driver, provided that he complies with the traffic regulations behaves, an intended overtaking first by setting one Blinkersignal the other road users, especially the road users driving ahead to be overtaken and also a possibly subsequent road users, announces and only after setting the Flashing signal by actively switching back or by stepping through the Accelerator pedal actually initiates the overtaking process.

This information given to the other road users as such registered by a sensor or controller and sent to the Control device could be passed on, the control device evaluate and from this an increased probability for one shortly derive a downshift command and a one engage the corresponding lower gear as a potential target gear, so to be able to react spontaneously to the expected downshift command.

In order to stick to the example of an overtaking maneuver, one such in usually through a fast, comparatively strong steering movement initiated. In another aspect, the invention therefore proposes to evaluate the driver's steering movements accordingly, from this possibly an increased probability of a shortly occurring Derive downshift command to a lower gear. Above all, it will thought that the control device is designed to increase the Probability of downshifting based on one Minimum steering angle exceeding the steering angle and / or on the basis a steering angle speed exceeding a minimum Detect steering angle speed.

In a further development it is further proposed that the control device for this is designed by means of that assigned to the coupling device Actuator system of the transmission input shaft, which has not yet been load-transmitting assigned clutch arrangement for preparing the overlap circuit partially, preferably until a friction limit is reached. The coupling arrangement in question can, for example, so far be indented that they are just a little or just yet Transmits moment. Through this "preparatory" engagement of the The clutch arrangement can react immediately to a downshift command and the Overlap switching can be made without the target gear bring the assigned clutch assembly into a "start position" have to.

It can advantageously be provided that the control device for this is designed on the basis of current and / or previous Driving conditions or / and on the basis of navigation data and / or on Based on driver dependent operation Operating states and / or based on states of the transmission or / and the drive unit or / and the coupling device or / and permissibility based on other conditions of the motor vehicle or it makes sense to insert one in relation to the exit gear check lower target gear and a corresponding gear than potential target gait in response to the flashing signal or in Reaction to the steering actuation exceeding the minimum actuation only in the event of an affirmative appeal. This can cause various circumstances be taken into account. For example, the control device should insert lower gear only when downshifting Speed limits, such as the drive unit (the engine), not be crossed, be exceeded, be passed.

Furthermore, the control device according to the suggestions in the mentioned patent DE 199 37 716 C1 can be designed. The Disclosure of this patent is incorporated by reference in its entirety Disclosure of the present application included.

The invention further relates to a control device for a Motor vehicle according to the invention. According to the invention, the control device is for this designed to have an increased likelihood of a downshift a target aisle lower than an exit aisle based on the Set a flashing signal and / or based on a one To recognize minimum actuation exceeding steering actuation and one corresponding gear as a potential target gear by means of a gear assigned actuator technology. The control device according to the invention can corresponding to the control device of the motor vehicle according to the invention be carried out as described above.

The invention is described below with reference to the figures illustrated embodiments explained in more detail.

Fig. 1 shows schematically a motor vehicle drive train with a multi-plate clutch and a powershift transmission, which has a control unit according to the invention.

Fig. 2 shows schematically a modification of the drive train according to FIG. 1, after which instead of a wet-running multi-plate clutch, a dry-running double clutch of the friction disc type is provided.

Fig. 1 shows an example of a drive train 10 of a motor vehicle. The drive train has a drive unit 12 in the form of an internal combustion engine, specifically an internal combustion engine, as indicated by a symbolically drawn crankshaft 14 . A so-called powershift transmission 18 with two radially nested transmission input shafts 20 and 22 is connected to the engine 12 via a double clutch 24 . The double clutch 24 comprises two clutch arrangements 26 and 28 , one of which is assigned to the transmission input shaft 20 and the other to the transmission input shaft 22 . The exemplary embodiment is a wet-running multi-plate clutch arrangement which can be actuated hydraulically by means of a respective hydraulic slave cylinder (not shown) integrated in the double clutch. A corresponding hydraulic pump 30 is shown schematically. A cooling oil circuit associated with the double clutch with a cooling oil pump etc. is not shown. Suitable double clutch constructions are known for example from DE 100 04 179 A1.

The actuation of the two clutch arrangements takes place by means of control valves 32 and 34 , which can be controlled electrically by a control unit 36 . The control unit receives input signals from an accelerator pedal 38 , a gear selector and / or influencing unit 39 , a speed sensor 40 assigned to the transmission input shaft 20 , a speed sensor 42 assigned to the transmission input shaft 22 and a speed sensor 44 assigned to the engine output shaft (crankshaft 14 ). The control unit can also receive further signals and measured values from other sensors and signal generators, for example a vehicle speed sensor, a steering angle sensor, a brake actuation state sensor (for example the brake pedal 46 shown in FIG. 1), etc.

By comparing the speed of the speed sensor 44 on the one hand and the speed of the speed sensor 40 or 42 on the other hand, the control unit can determine a slip state of the clutch arrangement 26 or the clutch arrangement 28 . The control unit 36 controls a power actuator of the engine 22 in order to set the power output or the torque output by the engine.

In Fig. 1, a crankshaft starter generator 50 is shown having a stator assembly 12 disposed and arranged on the input side of the dual clutch 24 to the engine rotor assembly. The crankshaft starter generator 50 is activated by the control unit 36 , in particular in order to handle the engine 12 .

Regarding the powershift transmission 18, which can also be referred to as a double clutch transmission, it should also be noted that it is preferably a fully synchronized transmission with a corresponding synchronizing device 52 . The synchronizing device 52 does not need to be a central synchronizing device for the entire transmission. The synchronizing device can also be formed by conventional synchronizing means, for example in the form of synchronizing rings. An output shaft of the transmission is designated 54. The transmission is preferably actuated in a fully automated manner by means of an actuating device 56 which can be controlled accordingly by the control unit 36 . By means of the gear selection or / and influencing unit 39 , the driver can instruct the control unit 36 to downshift to a lower gear or to shift up to a higher gear. In a fully automatic mode, the control unit switches automatically depending on the driving and operating conditions of the vehicle.

The switching between an output gear and a target gear takes place in usually by means of a so-called "overlap circuit" which assumes that in addition to the current load transfer Exit corridor in association with the other, currently not load-transferring Gearbox input shaft the target gear is already engaged, but that of not Coupling arrangement assigned to the load-transmitted transmission input shaft is disengaged. Then during the overlap circuit currently load-transmitting, assigned to the output aisle Clutch arrangement in terms of disengagement and that assigned to the target gear Coupling arrangement coordinated in terms of an engagement actuated to the drive torque of the drive unit from the Gearbox input shaft assigned to the output gear and thus from Output gear to the gear input shaft assigned to the target gear and thus to To shift target gear.

Fig. 2 shows another example of a drive train 10 of a motor vehicle. Only the changes compared to the drive train according to FIG. 1 are explained. Instead of a double clutch 24 with two wet-running multi-plate clutch arrangements 26 and 28 , in the example of FIG. 2, a double clutch 24 with two dry-running clutch arrangements 26 and 28 of the friction disc type is provided. The two friction disk clutch arrangements can be actuated hydraulically, for example by means of hydraulic slave cylinders integrated in the double clutch, which is assumed in FIG. 2. Corresponding implementation options can be found, for example, in DE 35 26 630 A1. Completely differently designed dry-running double clutches can also be used, for example, reference is made to EP 0 931 951 A1.

If a shift command is given manually by means of the unit 39 or the decision to shift by means of an overlap shift made by the control unit 36 in the fully automatic mode, delays are noticeably impairing the driving comfort. The control unit 36 is therefore designed according to the invention with a gear forecast functionality that predicts a probable target gear as a function of input data and already implements it in preparation for an expected overlap shift, although no shift command has been given by means of the unit 39 or a decision to shift in the fully automatic mode is not yet fallen. To this extent, the control unit 36 can be designed in accordance with the gear forecasting and gear selection device proposed in DE 199 37 716 C1 and can process various operating data as input data. Reference is made to the disclosure of DE 199 37 716 C1, which is fully incorporated by reference into the disclosure of the present patent application.

With regard to the preparation of a downshift to a lower gear, the control unit 36 is specially designed according to the invention to recognize an increased probability of a downshift to a lower gear compared to the output gear based on the setting of a flashing signal and a corresponding gear as a potential target gear by means of Insert actuator 56 . Furthermore, according to a preferred embodiment, the control device is designed to partially engage the clutch arrangement, which has previously been assigned to the precautionary gear already engaged and is not load-transmitting, by corresponding actuation of the valve arrangement 32 , 34 in preparation for the overlap shift, preferably until a friction limit is reached, so that in response to a shift command or on the decision to trigger a switching operation, the overlap switching can be carried out immediately, ie without a time delay.

With regard to the precautionary engagement of a potential target gear that is lower than the currently load-transmitting gear (the output gear) on the basis of the setting of a flashing signal, it is provided in the exemplary embodiments in FIGS . 1 and 2 that a corresponding turn signal control signal is supplied by a turn signal switch 60 alone or in addition to the control unit 36 becomes. If the driver actuates the turn signal switch 60 to announce an overtaking maneuver, the control unit 36 can recognize the increased likelihood of an impending shift to a lower target gear on the basis of the turn signal control signal supplied to it and, in response to this, engage the relevant lower gear (the potential target gear).

It makes sense to generally operate the turn signal switch by the driver of an increased likelihood of insertion a lower target gear compared to the current gear go out. Even when turning, which is done by a Corresponding flashing signal should be announced, as a rule either maintain the current gear or move to a lower gear connected.

Alternatively or additionally, the control unit 36 can recognize an increased likelihood of an impending shift to a lower target gear based on steering movements and, in response to this, engage the relevant lower gear (the potential target gear).

According to Fig. 1 (corresponding may also be provided for the embodiment of FIG. 2), the control unit 36 receives signals from a vehicle steering device 62. It could be provided, for example, that a current steering angle or changes in the current steering angle (possibly a steering angle speed) are detected by a corresponding sensor and fed to the control unit 36 in the form of corresponding signals. Since overtaking maneuvers in particular are usually initiated by a pronounced steering maneuver, the probability of an impending shift to the lower target gear in order to achieve a high vehicle acceleration can be recognized from this with a fairly high hit rate.

The control unit can add various other input data to your Take into account the prognosis of each target. The Control unit the admissibility or sensibility of inserting one in itself check the predicted finish and, if necessary, despite one current forecast that a particular target is likely to come soon should be activated by the precautionary engagement of this gear as anticipate potential finish. This check for admissibility or Meaningfulness can also be useful in relation to one Exit gear lower target gear take place, for example, to ensure that speed limits (such as the preferably not as a combustion engine) be crossed, be exceeded, be passed.

Claims (5)

1. Motor vehicle with a drive train which has a drive unit ( 12 ), a transmission ( 18 ) with a first and a second transmission input shaft and a multiple clutch device, in particular double clutch device ( 24 ), with a first one assigned to the first transmission input shaft ( 20 ) Coupling arrangement ( 26 ) and a second coupling arrangement ( 28 ) assigned to the second transmission input shaft ( 22 ) for torque transmission between the drive unit and the transmission, a control device ( 36 ) being provided by means of which an actuator system ( 56 ) assigned or associated with the transmission is provided. in correspondence to a respective one of the first and the second transmission input shaft, transmission gears can be engaged and disengaged and the clutch arrangements can be actuated by means of an actuator system ( 32 , 34 ) assigned or associated with the clutch device, the control device being designed to prepare for a transmission Intersection circuit, in which an output gear is assigned in association with a currently load-transmitting transmission input shaft and a target gear in assignment with a transmission load shaft that is not currently load-transmitting, and then the clutch arrangement assigned to the previously load-transmitting transmission input shaft in terms of disengagement and that assigned to the previously non-load-transmitting transmission input shaft Clutch arrangement is actuated in the sense of an engagement, to determine a probable target gear on the basis of input data and to assign this to the currently non-load-transmitting transmission input shaft as a potential target gear in addition to a gear engaged in assignment to the currently load-transmitting transmission input shaft that represents the output gear of the overlap shift to be prepared (hereinafter referred to as the exit gear), characterized in that the control device ( 36 ) is designed to recognize an increased probability of a downshift to a lower target gear compared to the output gear on the basis of the setting of a flashing signal and / or on the basis of a steering actuation exceeding a minimum actuation and to engage a corresponding gear as a potential target gear by means of the actuators. 2. Motor vehicle according to claim 1, characterized in that the control device ( 36 ) is designed to recognize the increased probability of downshifting on the basis of a steering angle exceeding a minimum steering angle or / and on the basis of a steering angle speed exceeding a minimum steering angle speed. 3. Motor vehicle according to claim 1 or 2, characterized in that the control device ( 36 ) is designed, by means of the actuator system ( 32 , 34 ) assigned to the clutch device, the clutch arrangement ( 26 or 28 ) assigned to the previously non-load-transmitting transmission input shaft in preparation for the Partially overlap circuit, preferably until a friction limit is reached. 4. Motor vehicle according to one of claims 1 to 3, characterized in that the control device ( 36 ) is designed on the basis of current and / or previous driving conditions and / and on the basis of navigation data and / and on the basis of the actuation by a driver-dependent actuation states and / or on the basis of states of the transmission ( 18 ) or / and the drive unit ( 12 ) or / and the coupling device ( 24 ) or / and on the basis of other states of the motor vehicle the admissibility or sensibility of inserting one to check the exit gear of the lower target gear and to select a corresponding gear as a potential target gear in response to the flashing signal being set or in response to the steering actuation exceeding the minimum actuation only in the event of an affirmation. 5. Control device for a motor vehicle according to one of the preceding claims, characterized in that the control device ( 36 ) is designed to increase the probability of a downshift to a lower gear compared to the output gear based on the setting of a flashing signal and / or on the basis of a to recognize a steering operation that exceeds a minimum actuation and to engage a corresponding gear as a potential target gear by means of the actuator system.