DE10157943A1 - controlling drive system with drive unit and automated gearbox arrangement for vehicle, involves inhibiting gear disengagement while driver demanding drive torque if driver also requests gear shift into neutral - Google Patents

Abstract

The method involves inhibiting gear disengagement in the gearbox arrangement (26) while the driver is demanding the output of drive torque from the drive unit (12) if the driver demands a gear shift into neutral while a gear is engaged and the drive unit is delivering drive torque to the gearbox arrangement. If the driver then fully releases an operating element (62) the gearbox arrangement automatically shifts to neutral.

Description

The present invention relates to a method for driving a Drive system, which drive system is a drive unit as well has an automated transmission arrangement.

In such drive systems, in which automation various system components, such as B. the gear arrangement or a possibly also existing clutch arrangement, the implementation of Steps in these various system components in the Generally commanded by a control device exists the problem that even the driver by acting on the system Actuating processes that can lead to a potentially dangerous or critical situation regarding damage to the system can. The transition from one to another, for example, is problematic State in which a gear is engaged in the transmission arrangement in a state in which no gear is engaged in the transmission arrangement and vice versa, for example, by activating an as Actuator provided accelerator pedal the driver nevertheless an influence to the speed of the drive unit or that of the drive unit output torque can take.

It is therefore the object of the present invention to take measures to provide with which in the transition between a neutral state and a state with the gear engaged in the transmission arrangement Avoidance of potentially critical or uncomfortable driving conditions avoided can be.

According to a first aspect of the present invention, this object is achieved solved by a method for controlling a drive system, which Drive system, a drive unit and an automated one Gear arrangement, in which method, when when inserted Gear and from the drive unit to the transmission arrangement Drive torque a driver a command to switch the Gear arrangement generated in a neutral state, the design of the gear stage is stopped for as long as long as the driver submits a Drive torque is required by the drive unit.

This measure prevents, for example, if a driver mistakenly while the vehicle is in motion operated a gear lever or selector lever and thereby actually the Gear arrangement would be to be switched to a neutral state, however, the accelerator pedal is operated undiminished, the drive unit due to a sudden loss of load, which occurs when a gear is disengaged would occur. Only when there is no moment request there is more from the driver, the gear ratio is permitted. The driver intentionally has the shift lever to disengage the gear or for switching the gear arrangement into a neutral state actuated, it generally also becomes the accelerator pedal at the same time release, so that the gear step is actually without delay will be done. However, the driver has to operate the gear lever without Intentional or disregarding the operation of the accelerator pedal made, the measure according to the invention can Damage to the power pack by reaching excessive high speed can be prevented.

According to a further aspect of the present invention, the The above-mentioned object is achieved by a method for controlling a Drive system, which drive system is a drive unit and a automated transmission arrangement, in which method then when the gear assembly is in a neutral condition, turning the drive unit with a speed above a threshold is prevented. This measure ensures that, for example at a traffic light and in the neutral position gearbox an unintentional or uncontrolled actuation of the Accelerator pedal or any other actuator not to one excessive driving of the drive unit.

However, in order to be able to take this measure into account that a driver may have a sporty start wants to perform higher speed, it is proposed that the threshold in Depends on the extent of actuation of an actuator is selected. For example, the threshold can increase with increasing Actuation range increase.

According to a further aspect of the present invention, the The above-mentioned object is achieved by a method for controlling a Drive system, which drive system is a drive unit and a automated transmission arrangement, in which method then when generating a command to shift the transmission arrangement from a neutral state to an in-gear state from Driver is generated and the speed of the drive unit above one Threshold is, the speed of the drive unit to a below or in Range of the threshold speed is set.

This measure takes into account the state in which, starting from the driver wishes to start from a neutral state of the vehicle and at the same time, for example, the accelerator pedal as Actuator for requesting a start-up or a Starting torque and a shift or selector lever actuated. The speed reaches thereby in an area which is used to carry out a subsequent Start-up or clutch engagement is potentially critical the measure according to the invention be ensured that by Reduction of the speed to one in the range of or below the threshold prevent dome bumps or jerky starts become.

It can also be advantageous here to set the threshold as a function of Extent of actuation of an actuator, such as. B. one Accelerator pedal.

Even when the vehicle is in a driving state, it can For example, it may be possible for the driver to or selector lever brings the transmission into a neutral condition and then tried by pressing the shift or selector lever again Gear arrangement again in a torque transmitting state bring. In this case, according to an advantageous aspect, the The present invention further provides that the threshold in the range the speed of a transmission input shaft is selected, d. H. the Drive unit is controlled such that its speed in the range of Speed of the transmission input shaft lies, so that a subsequent Coupling process to be carried out essentially without coupling joints can be done.

To ensure that the change in the speed of the Drive unit in the direction of the predetermined threshold as fast as possible, it can further be provided that during the Changing the speed of the drive unit between the Drive unit and the transmission arrangement acting coupling arrangement in Is adjusted in the direction of engagement.

According to a further aspect of the present invention, the The above-mentioned object is achieved by a method for controlling a Drive system, which drive system is a drive unit and a automated transmission arrangement, in which method then if a vehicle is longer than one with the drive unit running predetermined period of time with the gear engaged in a standstill state is held, the gear arrangement is switched to a neutral state and, when the driver generates a start request, in the gear arrangement a gear stage and a speed or only then increases a drive torque of the drive unit when a gear is engaged in the transmission arrangement.

This measure also ensures that when starting again after a longer standstill phase, during which also from economic Reason the gearbox was switched to a neutral state, the speed not excessively strong due to excessive actuation of the accelerator pedal can rise before the gear is engaged. It should be taken into account here that for the driver this is temporarily when the vehicle is at a standstill gear selection made in general will not be recognizable. Therefore, he will not take it into account when restarting that a gear has to be put in first and first then the vehicle is in a state ready to start. Through the The measure according to the invention specified above is a security against unintentional revving of the drive unit in it Condition given.

According to a further aspect of the present invention, the The above-mentioned object is achieved by a method for controlling a Drive system, which drive system is a drive unit and a automated transmission arrangement, in which method then when a vehicle is in a driving state and a defect in the Drive system is recognized, the gear arrangement in a neutral State is switched and the speed of the drive unit in the area a target speed or below a threshold.

When a defect in the drive system is detected, it is common Emergency measures taken, which u. a. also switching the gear arrangement in include a neutral state. Since these emergency measures for the Drivers are often taken in a surprising way and thus the there is a potential risk that the still existing speed or torque request when the load is no longer present Turning the drive unit up can do this with the transition to neutral State accompanying adjustment of the speed of the drive unit a predefined setpoint here undesirable loss of comfort or Prevent damage in the area of the drive unit.

The present invention will hereinafter also be described with reference to FIG enclosed figure described in detail. This figure shows a drive system in which the measures according to the invention are applied can.

The drive system 10 comprises a drive unit 12 , for example an internal combustion engine 12 , which is connected via a drive shaft 14 to an input side 16 of an automated clutch arrangement 20 , for example a friction clutch. An output side 22 of the clutch arrangement 20 is in drive connection with an automated transmission arrangement 26 via a transmission input shaft 24 . Its output shaft 28 drives wheels 32 , 34 via a differential 30 . The drive unit 12 , the clutch arrangement 20 and the transmission arrangement 26 are controlled by a control device 36 . This drive apparatus 36 is in Datentaustausch with a power actuator assembly 38 of the drive unit in order to control and 12 respectively to be regulated by the supply of control signals or commands to the power actuator assembly 38 the power output of the rotational speed of the drive assembly. It should be pointed out that the power control arrangement 38 comprises any area of a drive unit in which an influence on its speed or power output can be exerted, for example the injection system, the throttle system, the ignition system, the cam system, etc. Of course, the power control arrangement 38 provides information to the Control device 36 , which denotes the power setting state of the drive unit 12 .

Furthermore, the control device 36 is connected to an actuator arrangement 40 of the automated clutch arrangement 20 in order to adjust the clutch arrangement 20 between an engaged and a disengaged clutch position by supplying corresponding actuating signals. The actuator arrangement 40 can also supply the control device 36 with information which denotes the current actuating state of the clutch arrangement.

In addition, the control device 36 supplies control signals to an actuator arrangement 42 of the transmission arrangement 26 . These control signals lead to switching operations being carried out within the gear arrangement 26 . Here too, the control device 36 is again supplied with information which denotes the current actuating state of the gear arrangement 26 . The control device 36 also receives information I from various sensors, based on which information the control device 36 can determine the overall operating state of the vehicle. For example, a speed sensor 44 is provided, which detects the speed of the drive shaft 14 . It should be pointed out that, provided that the speed is being recorded, this naturally also includes the detection of any information characterizing the speed, which is then processed, for example, in the control device 36 for actually determining the speed per se. Furthermore, a speed sensor 46 is provided, which detects the speed of the transmission input shaft 24 , and a speed sensor 48 , which detects the speed of the transmission output shaft 28 . Furthermore, speed sensors 50 , 52 are provided which detect the speed of the driven wheels 32 , 34 or of the shafts 54 , 56 driving them. The vehicle speed can be calculated based on these two sensor outputs or based on the output of the speed sensor 48 ; ie these sensor outputs from sensors 48 , 50 , 52 contain information about the vehicle speed.

Furthermore, a switching sensor 58 is provided, which detects an actuation of a switching lever 60 and supplies corresponding information I to the control device 36 . Based on this information, the control device 36 recognizes which shift operation a driver wants to carry out and then generates a suitable control command for the transmission arrangement 26 at the appropriate time and, if necessary, taking into account the further information representing the driving state. It should be pointed out that instead of detecting the shift lever actuation, a shifting operation can also be carried out in the manner of an automatic transmission based on the driving situation.

In the drive system 10 , an accelerator or accelerator pedal 62 is also provided with an associated accelerator pedal sensor 64 , the output signal of which represents the extent of actuation of the accelerator pedal. A brake pedal 66 is also provided, to which a sensor 68 is also assigned. The output signal of this brake pedal sensor 68 represents the actuation amount of the brake pedal 66 .

Based on all of these sensor inputs and possibly further sensor inputs, for example from an ambient temperature sensor, a coolant temperature sensor, a yaw motion sensor and the like, the control device 36 generates various control commands or control specifications, which are then in the various units or components to be controlled, i.e. the power control arrangement 38 , the actuator arrangement 40 and the actuator arrangement 42 are implemented, ie lead to the implementation of steep steps in the drive unit 12 , in the clutch arrangement 20 or in the transmission arrangement 26 . These control specifications are determined in the control device 36 in a processor, in which a corresponding control program runs, which receives the various sensor inputs I as input and which generates a control specification as an output, which either leads directly to the various control ranges 38 , 40 , 42 as a control command is, or which is subsequently converted into a respective control command in the control device 36 and only then directed to the control ranges.

In a drive system, as shown in the figure, the driver can generate shift commands by actuating the shift lever 60 , which are then executed by appropriate control by means of the control device 36 in the gear arrangement 26 . This means that the driver can basically also switch between a neutral state in which no gear is engaged in the gear arrangement 26 and a state in which a gear is engaged in the gear arrangement 26 and thus transmit or transmit torque via the gear arrangement 26 can be changed in it. This means that the driver can switch between a driving mode and a neutral mode. In principle, there is also the risk that this actuation of the shift lever 60 by the driver also occurs at a time when switching between the different modes is problematic. For example, such a state exists when the vehicle is in the driving state, that is to say a torque is output by the drive unit 12 and is transmitted via the transmission 26 . In this state, the driver will have at least partially depressed the accelerator pedal 62 in order to request a specific torque or a specific speed from the drive unit 12 . If, for example, the driver also mistakenly actuated the shift lever 60 in such a way that a shift command for shifting to the neutral state would have to be generated for the transmission arrangement 26 , this would have the consequence that the continued operation of the accelerator pedal 62 and the one that then occurs If there is no load, the drive unit 12 turns up and comes into a critical speed range. According to the invention, in this case, that is, if the driver generates a command to shift the transmission arrangement 26 into a neutral state when the accelerator pedal 62 is actuated and the vehicle is in the driving state, the corresponding shifting process in the transmission arrangement 26 is prevented until it is carried out by the sensor 64 is recognized that the actuation of the accelerator pedal 62 is released, which also includes the case that the actuation of the accelerator pedal 62 has dropped below a certain extent. Only then is the gear shift 26 carried out to shift the gear to the neutral state. In this case, for example, the procedure can be such that the corresponding command is only generated in the control device 36 or that a locking member in the gear arrangement 26 releases the switching operation.

Another critical state is when the driver actuates the accelerator pedal 62 excessively when the transmission arrangement is in the neutral state. In this state too, the drive unit 12 is essentially load-free, and excessive actuation of the accelerator pedal 62 would result in the drive unit 12 being correspondingly excessively turned up. To ensure safety here, it can be provided that in this state an upper limit speed is specified for the drive unit 12 , which then must not be exceeded. This upper limit rotational speed, which functions as a threshold, can also be dependent, for example, on the actuation of the accelerator pedal 62 , where the threshold is also shifted to larger rotational speed values with increasing extent of the actuation of the accelerator pedal 62 . The state can thus be taken into account that, for example, the driver wishes to start in a more or less sporty manner and therefore already actuates the accelerator pedal 62 in anticipation.

Another critical state is the transition from a neutral state to a state in which a gear is engaged in the transmission arrangement 26 when the driver also actuates the accelerator pedal 62 and thus the speed of the drive unit 12 increases too much or already in one high range. Here, according to the invention, safety can be ensured by intervening in the engine management, ie by generating appropriate control commands by means of the control device 36 , to reduce the speed of the drive unit 12 until it is, for example, in the range or below a threshold which may again be dependent on the accelerator pedal actuation. This state can fundamentally also occur if the driver has also inadvertently selected the gear by actuating the shift lever 60 when the vehicle is moving and subsequently wishes to engage a gear again by actuating the shift lever 60 again. In this state too, by intervening in the engine management, ie by generating corresponding control commands for the drive unit 12 , it is ensured that the speed of the drive unit 12 is in a suitable range. The drive unit 12 is preferably set to a speed which is in the range of the speed of the transmission input shaft 24 , so that the occurrence of coupling shocks can be avoided.

With the measures described above, in which safety is ensured when engaging a gear stage by engaging in the control of the drive unit 12 , it can further be proceeded in such a way that, in addition to this intervention in the engine management, the clutch arrangement 20 is also at least partially engaged in order to the friction torque generated in the clutch assembly 20 to support a faster lowering of the speed of the drive unit 12 . Of course, it is also possible to engage the clutch arrangement 20 only when the speed of the drive unit 12 is in the desired range.

In drive systems, as shown in the figure, it can further be provided that when the vehicle is at a standstill for a long time, for example at a traffic light, in a traffic jam or the like, with the drive unit 12 running and in a state with an engaged gear located transmission arrangement 26 is generated by the control device 36 a command to disengage the gear and thus to transition to the neutral state, although the driver has not actuated the shift lever 60 . This layout of the gear is generally not noticeable to the driver. If the driver subsequently actuates the accelerator pedal 62 to start again, the gear that was previously engaged, for example, generally a starting gear, is engaged again. Especially in gears, the engagement of which takes a comparatively long time, according to a further aspect of the invention, the procedure can be such that, despite actuation of the accelerator pedal 62 , the speed of the drive unit is initially kept in the range of the idling speed or another target speed, and only when the gear 26 is engaged or a corresponding signal is supplied by the transmission arrangement 26 , the speed of the drive unit 12 is increased by generating corresponding control commands in order to reach a region corresponding to the actuation of the accelerator pedal 62 . This also prevents an excessive actuation of the accelerator pedal 62 due to the fact that the driver was not aware that no gear is engaged at all, and does not result in the drive unit being excessively turned up.

Another potentially critical state is when it is recognized in the drive system 10 based on various sensor outputs that a defect is present. Such a defect, for example, a pressure fluid leakage when actuated by pressure fluid coupling assembly 20 and gear assembly 26th A pressure fluid leakage can have the consequence that these system components can no longer be actuated, ie the clutch arrangement 20 can no longer be disengaged or gear changes can no longer be carried out in the transmission arrangement 26 . Since pressure drops generated by such pressure fluid leaks generally do not occur spontaneously, there is still a certain time within which safety measures can be taken to avoid the occurrence of a potentially dangerous situation. Such a safety measure is the switching of the gear arrangement 26 into the neutral state, in order to be able to tow the vehicle, for example, subsequently even when the clutch arrangement 20 can no longer be actuated, ie can no longer be disengaged. Since this switching to the neutral state can also come as a surprise to the driver and he initially still depresses the accelerator pedal 62 to a certain extent in the driving state, according to a further aspect of the present invention, a gearbox arrangement 26 is activated if a safety measure is taken Gear is designed by appropriate control of the drive unit 12 whose speed is reduced or kept in a range that is not critical. For example, a threshold or a target speed can be provided here, to which the drive unit 12 is then brought. This target speed can also be in the range of the idling speed, for example.

Various measures are provided by the present invention provided that ensure that in case of unwanted or for the driver too unexpected or unrecognizable transitions between a neutral state of the gear arrangement and a state in which a gear is engaged in the area of the drive unit Reaching excessively high speeds is avoided or ensured is that these states cannot occur at all. This increases general safety when using one with such System equipped vehicle and performs in different Driving conditions also for improved driving comfort.

Claims (12)

1. A method for actuating a drive system, which drive system ( 10 ) has a drive unit ( 12 ) and an automated transmission arrangement ( 26 ), in which method when drive torque delivered to the transmission arrangement ( 26 ) by the drive unit ( 12 ) and from the drive unit ( 12 ) a driver generates a command to shift the transmission arrangement ( 26 ) into a neutral state, the design of the gear stage is prevented as long as the driver is required to supply a drive torque from the drive unit ( 12 ). 2. The method according to claim 1, characterized in that when the driver releases an actuating member ( 62 ) substantially completely, the transmission arrangement ( 26 ) is switched to the neutral state. 3. Method for controlling a drive system, which drive system ( 10 ) has a drive unit ( 12 ) and an automated transmission arrangement ( 26 ), in which method, when the transmission arrangement ( 26 ) is in a neutral state, the rotation of the drive unit ( 12 ) is prevented with a speed above a threshold. 4. The method according to claim 3, characterized in that the threshold is selected depending on the extent of actuation of an actuating member ( 62 ). 5. The method according to claim 4, characterized in that with increasing Extent of actuation the threshold increases. 6. A method for actuating a drive system, which drive system ( 10 ) has a drive unit ( 12 ) and an automated transmission arrangement ( 26 ), in which method when generating a command to switch the transmission arrangement ( 26 ) from a neutral state to one Condition with the gear engaged is generated by the driver and the speed of the drive unit ( 12 ) is above a threshold, the speed of the drive unit is set to a speed below or in the range of the threshold. 7. The method according to claim 6, characterized in that the threshold is selected depending on the extent of actuation of an actuating member ( 62 ). 8. The method according to claim 6 or 7, characterized in that when the vehicle is in a driving state, the threshold in the range of the speed of a transmission input shaft ( 24 ) is selected. 9. The method according to any one of claims 6 to 8, characterized in that while changing the speed of the drive unit ( 12 ) between the drive unit ( 12 ) and the gear arrangement ( 26 ) acting clutch arrangement ( 20 ) is adjusted in the direction of engagement. 10. A method for controlling a drive system, which drive system ( 10 ) has a drive unit ( 12 ) and an automated transmission arrangement ( 26 ), in which method if a vehicle with the drive unit ( 12 ) running for longer than a predetermined period of time with the gear engaged is held in a standstill state, the transmission arrangement ( 26 ) is switched into a neutral state, and then, when the driver generates a start request, a gear stage is engaged in the transmission arrangement ( 26 ) and a speed or a drive torque of the drive unit ( 12 ) is only increased when a gear is engaged in the gear arrangement ( 26 ). 11. A method for actuating a drive system, which drive system ( 10 ) has a drive unit ( 12 ) and an automated transmission arrangement ( 26 ), in which method when a vehicle is in a driving state and a defect in the drive system ( 10 ) is detected , The gear arrangement ( 26 ) is switched to a neutral state and the speed of the drive unit ( 12 ) is set in the range of a target speed or below a threshold. 12. The method according to claim 11, characterized in that as a defect a successful or expected failure of actuation in the area of the gear arrangement ( 26 ) and / or in the area of a coupling arrangement ( 20 ) acting between the drive unit ( 12 ) and the gear arrangement ( 26 ) becomes.