FR2797480A1 - METHOD FOR CONTROLLING A DRIVE SYSTEM AND DRIVE SYSTEM FOR IMPLEMENTING THE METHOD - Google Patents

Abstract

Method for controlling a drive system (10) comprising a motor (12), a clutch (18) and a gearbox (24). According to the method, it is checked whether the engine (12) is running, whether a speed has shifted in the gearbox (24) and to what extent the accelerator pedal (56) has been actuated. In the event of a positive answer to this question, and if the accelerator pedal has been actuated for a speed other than zero and less than the garage maneuvering threshold, the clutch (18) is controlled to adjust a maneuvering setpoint speed. predetermined.

Description

Description

  The present invention relates to a method of

  control of a drive system comprising a modular unit

  trice, an automatic clutch and a gearbox, preferably an automatic.

  In such automatic drive systems

  ques, the general difficulty is that at the stop or in case of

  very slow movement, the driver can no longer, when driving

  erasing the clutch pedal and thereby interrupting more or

  less strongly the transmission line, move the vehicle

  runs slowly and in a measured manner, for example for a garage or storage maneuver or to hold the vehicle on a

  sloping road, or prevent the vehicle from rolling back. At the con-

  milking, the driver must maneuver the vehicle in such

  situations simply by depressing the accelerator pedal

  lerator, so that due to this depression, the clutch is more or less strongly engaged to transmit torque

  set point, usually predetermined. But it ends fref-

  only to the disadvantage of being able only with difficulty

  run the vehicle slowly and at a metered rate, especially

  link on downhill roads.

  Document DE 197 33 465 A1 describes a device

  tif for controlling an automatic clutch; according to this provision

  If there is a difference between the different rolling states, in particular if the vehicle is traveling in the wrong direction, that is to say for example if it is reversing

  while the first speed has passed, the clutch

  ge is engaged to oppose the rolling of the vehicle in the

Wrong direction.

  The object of the present invention is to develop a method for controlling a drive system or a system

  which, in particular when stationary or moving slowly, guarantees

  tit against unwanted movement of the vehicle.

  To this end, the invention relates to a process of the 3S type defined above, characterized in that a) it is detected whether the motor unit is operating,

  b) it is detected if a gear has shifted into the gearbox

  braids, c) it is detected to what extent a driving actuation installation, preferably an accelerator pedal has been actuated, then

  d) if it has been observed in step a) that the motor unit functions

  in step b) that a gear ratio is passed

  in the gearbox, preferably the shift speed

  mooring, and in step c) that the driving actuation installation has been maneuvered but according to a degree of maneuver lower than the degree of actuation of a garage maneuvering threshold, the clutch is controlled to

  set a preset garage maneuver speed

  determined. An important characteristic of the process of the invention is that in particular in a rolling situation in which the driver wishes to carry out a storage maneuver for the vehicle, that is to say for a maneuver

  in the garage, a controlled speed is adjusted

  operating error, predetermined, and the vehicle is not

  placed directly according to the actuation of the installation

  driving relationship. This means that as long as the

  degree of actuation of the actuation system

  this pick remains below the set actuation degree,

  the system certainly recognizes that the driver wants to move

  cer but only at a very low speed. But as with a low degree of actuation, of this type, it is often extremely difficult for the driver to define in a desired manner a desired speed and which is thus risked by a

  slightly too strong actuation of the action system-

  In addition, to trigger a strong reaction from the vehicle; in this driving situation, the vehicle moves according to the planned storage set speed; the driver will have a fully defined and calculable reaction from the vehicle

  when the driving actuation system is light-

  maneuvered. This greatly simplifies the operation

  because the driver knows how the vehicle

  gira to such a weak actuation. It is only if it continues to act on the actuating installation, and it exceeds the set point corresponding to the storage maneuver, that the clutch is for example re-ordered according to the degree d actuation of the actuation system, to move the vehicle during normal movement or in motion

  very slow as desired by the driver.

  To avoid in particular during parking maneuvers performed on a sloping road, that the control of the clutch system and the resulting increase in the clutch torque transmitted, too strongly throttles the rotation speed of the drive unit, it is proposed that

  the drive unit is also controlled to adjust the speed

  set size of the storage maneuver.

  To avoid excessive stress on the clutch, it is proposed that the clutch, or preferably the drive unit, is not controlled to regulate the speed of

  storage instruction only when the brake is not applied-

  born. It can also be provided that the set speed of the storage maneuver is a speed other than zero and is in a range of up to 5 km / h, preferably

up to 3 km / h.

  The problem mentioned above is also solved by a drive system comprising: - a motor unit, connected or capable of being connected by

  an automatic clutch to a gearbox, pre-

  refers to an automatic gearbox for producing a torque transmission link, - a driving actuation installation, preferably an accelerator pedal for controlling the drive unit according to the degree of actuation for the torque to be supplied, - a speed recording device,

  - a control system for controlling the mo-

or / and the clutch.

  According to the invention, it is intended that the installation

  control lation controls the clutch to adjust a speed

  predefined garage maneuvering target size, if the drive unit is used, if a gear ratio, preferably the starting speed, has been

  gearbox and if the operating system of con-

  this pick is actuated according to a degree other than zero, located below the degree of actuation of the garage parking instruction. In such a system it is also advantageous

  that the control system additionally controls the mo-

  to set the speed to the setpoint speed

garage work.

  According to another advantageous characteristic of the invention, the problem mentioned above is solved by a method of controlling a drive system, this system comprising a drive unit, an automatic clutch (18)

  and a gearbox, preferably an automatic gearbox

  that, characterized in that a) it detects if the drive unit is operating, b) it detects if a gear ratio has passed through the gearbox, c) it detects if a driving actuation installation, preferably the accelerator pedal, has been actuated, then, d) if it has been detected that, in step a), the power unit

  in step b) only one speed, preferably

  the starting speed, went into the gearbox and in step c) that the installation

  drive actuation has not been actuated, we understand

  requests the clutch system to adjust a speed

predetermined set point.

  This process corresponds in particular to a state of con-

  pick in which the vehicle is on a very pavement

  on a slope, so that for example in the event of an overhang

  tagne, that is to say when a forward speed ratio is

  past, there is a risk of stopping, that is to say when the installation

  the drive actuation action has not been actuated, the vehicle escapes and reverses. The determined setting of a predefined target speed allows the clutch system control to ensure that the vehicle is maintained

  stopped or even slowly moved in the direction

tion desired.

  We can for example plan not to order

  the clutch only for a speed other than zero km / h.

  This set speed can for example be a speed equal to zero km / h. As a variant, it is also possible to give the set speed a value such

  that by passing the gear ratio, the speed in the di-

  desired rection differs from zero speed by one degree corresponds to the resolution of the speed of a

speed input.

  As already explained, it may be advantageous in this procedure that in addition, the motor unit is controlled

  to set the target speed.

  According to another characteristic of the present invention, the drive system comprises a motor connected to a gearbox by an automatic clutch, the gearbox being preferably automatic, for torque transmission, a driving actuation installation, preferably an accelerator pedal, which can control

  the drive unit according to the degree of actuation of this

  dale, to provide a torque, a drive unit input device and a unit control installation

drive or / and clutch.

  For this, the control system acts on the clutch to regulate a target speed if the drive unit is started, if a speed has shifted into the gearbox, preferably the starting speed, and if the pipe actuation facility has not yet

been activated.

  As already mentioned, the set speed can be at zero km / h; we can also provide a speed of

  setpoint other than zero km / h, within a resolution range

  speed of the speed input device, in the

  direction set by the past gear ratio.

  According to another advantageous characteristic,

  the drive unit is controlled to adjust the speed of

  sign. To allow in this procedure as well as in the drive system, to avoid an overload of

  the clutch, it is proposed that the clutch and / or the unit

  only be controlled by the control system for

  set the target speed, only if the brake is not activated

  tionné. The present invention will be described below in more detail using an embodiment of a drive system, shown schematically in the

pic attached figure.

  According to the invention, the drive system 10

  comprises a drive unit 12, for example a motor with

  internal bust 12 coupled by its motor shaft 14 to the input

  16 of an automatic clutch generally bearing the reference

  rence 18. The output of the clutch 18 is connected by a shaft

  gearbox input 22 to a gearbox

  tomatic generally bearing the reference 24. The box of

  gears 24 drives two driving wheels 30, 32 by the

  gearbox output shaft 26 and

a differential 28.

  The drive system 10 further comprises a

  control device 34 which, as will be described later

  laughingly, cooperates with the various groups and components of this drive system 10. The control installation 34 thus controls the drive unit 12 via a

  power adjustment device 36 associated with the motor 12.

  It should be noted that this power adjustment device 36 includes any means controlled to modify the power supplied or the torque supplied by the power unit 12, for example the injection, the throttle valve, the system

  ignition system, the camshaft system or the like

  gues. This power adjustment device 36 thus contains

  control orders corresponding to the installation of

  command 34 to define the desired output torque for the drive unit 12 or the variation of the desired output rotational speed. Correspondingly, the power adjustment device 36 provides information to the control installation 34 to thereby deduce the state of

  instantaneous operation of the power unit 12.

  The clutch 18 comprises an associated actuator 38 which cooperates alternately with the control installation 34

  to receive orders from it for a corresponding adjustment

  clutch or disengagement clutch, as well as the clutch torque transmission capacity 18. The actuator 38

  may further provide information regarding the

  control unit 34 representing the instantaneous actuation state

  clutch 18. This information can be provided.

  by other sensors provided in the clutch 18.

  The automatic gearbox 24 includes an actuator 40 which engages or releases the gear ratios

  in box 24 under the control of the installation of

  command 34. This command can be done for example using

  a gear lever bearing the reference 42; this action-

  This is for example detected by a gear lever sensor 44 which gives a corresponding signal (arrow I)

  transmitted to the control system 34.

  The drive system furthermore comprises

  sensors or sensor devices for detecting different

  many other operating states. Thus, a speed sensor 46 is associated with the output shaft 14 and a speed sensor 48 with the input shaft 22 of the gearbox. A rotational speed sensor 50 is associated with the output shaft 26 of the gearbox and

  the speed of rotation of the driving wheels 30, 32 may also

  ment be detected by associated sensors 52, 54. These diff-

  different sensors each provide respective input signals giving direct or indirect information of the respective rotation speed or that of the different

  control system components 34.

  The drive system 10 comprises an accelerator pedal 56 constituting a driving actuation installation; the degree of actuation of the accelerator pedal is transmitted to the control system 34 by a corresponding sensor device. Depending on this degree of actuation, the control installation 34 receives

  then, from the power control installation 36, or-

  command dres to adjust the power requested to the power unit 12. One can also use other states of

  operation or signals to control the power unit 12.

  The drive system 10 further comprises a brake pedal 58 whose actuation or degree

  actuation is also supplied to the installation of

  requires 34 to be treated. It is possible to provide other sensors generally bearing the reference 60. These other sensors can for example provide information concerning the slope of the roadway, the vehicle load, the coefficient

  road surface adhesion or similar information.

  When a vehicle fitted with such an ignition system

  dragging is controlled for example to perform a maneuver

  slow speed garage glass, the system of the invention allows

  proceed as follows: as a point of

  At the outset, there is an operating state in which the unit

  trice 12 is started, a gear is passed into the gearbox 24 for starting, that is to say for example the first or second speed forward or reverse; first the accelerator pedal

  56 is not applied but the brake 58 is pressed to stop

  stop the vehicle. These different operating states

  can be captured by the sensors mentioned above,

  linked to different sets or by exploitation

  corresponding sensor signals, allowing

  close to the existence or not of the different functional states-

  ment. In particular to capture the start-up of the drive unit 12, it is possible to detect for example that the ignition key is in the operating position, or for example to use the speed signal of the sensor 46 to find out that the drive unit 12 is on the way, if at the same time for example the sensors 52, 54 indicate that the vehicle is not moving, or that the actuator 38

  provides information that the clutch 18 is out

  locked and in this case the shaft 14 cannot be moved

  by a vehicle in circulation. If then the accelerator pedal 56 is slightly depressed, whereby the driver indicates that he wishes the movement, but with a very low speed, this wish of the driver is recognized by

  the control system 34 in that the degree of ac-

  detected throttle pedal 56 is compared

  at an amplitude of actuation of the maneuvering threshold

  rage. If the degree of effective actuation is below

  below the degree of actuation of the garage maneuvering threshold, i.e. if the entire actuating stroke of the accelerator pedal 56 is used only in an extremely small range, for example up to 5%, there is a control of the clutch 18, that is to say of the actuator 38 which is associated with it to engage the clutch 18 and increase the torque transmitted by the clutch. This command does not

  However, this is only done if by pressing the accelerator pedal.

  accelerator 56 we also released the brake pedal 58, which is generally to be expected since the two pedals

  must be operated by the driver with the same foot.

  From the actuation of the clutch, in the direction of engagement, a more intense torque is transmitted by the drive unit 12 to the part of the drive system, downstream of the clutch 18 and thus the vehicle starts to

  roll. This bearing is picked up in particular by the cap-

  rotational speed sensors 48, 50, 52, 54; it is enough here

  of one of the sensor signals to deduce the speed ef-

  fective of the vehicle. The vehicle speed thus obtained, or defined in the control installation 34, is compared with a set point value of the garage maneuvering speed corresponding to this situation; if the speed detected or obtained is then below this set value, the clutch can be controlled in the direction of engagement whereas if the speed entered, obtained, exceeds this value of

  setpoint, the clutch is actuated in the release direction.

  Thus, in a regulation loop, the speed of the vehicle is adjusted to a speed which is at the level or in the zone

  of the garage maneuver setpoint speed.

  To avoid a too strong thrust of the speed of rotation of the driving unit 12 by the increasing engagement of the clutch 18, if from the signal or the signals of the sensor 46 it is recognized that the speed of rotation of the unit drive 12 decreases too strongly, it is controlled to increase the torque supplied. The drive unit control

  depends on each respective case or on the need to pro

  to protect against a strong thrust of the speed of rotation.

  In internal combustion engines with a large displacement, there is a risk of stalling or causing an excessively strong thrust of the rotation speed, even a relatively low one, so that for example the sole control of the clutch 18 may be sufficient. In the case of smaller internal combustion engines of lower power, it may be advantageous, at the same time as engaging the clutch 18, to increase the required power of the engine 12 to avoid jolts or stalling the engine 12. In this case, it is also possible to use the information concerning the slope of the roadway or the load of the vehicle because the load of the power unit increases further

  for slow movements performed on a slope.

  The method according to the invention, according to which, for a weak actuation of the accelerator pedal 56, the clutch 18 or the engine 12 or the corresponding actuators 36, 38 are not directly controlled in a corresponding manner, but according to which we set a certain speed, present

  the considerable advantage that the inaccuracies of the action-

  when depressing the accelerator pedal 56

  cannot result in an uncontrolled movement of the vehicle. This-

  it considerably facilitates garage maneuvers for the driver since he does not have to regulate the depressing of the accelerator pedal very precisely. On the contrary, the driver knows that for a weak actuation of the accelerator pedal, he will have a defined reaction of the vehicle, to

  know a movement at a determined speed. To do not-

  if the vehicle is in normal traffic, it continues

  depress the accelerator pedal 56 so that it exceeds

  the degree of threshold actuation of the safety maneuvers

  rage, the clutch 18 or the drive unit 12 are controlled

  directly depending on the degree of actuation.

  In addition, when the action on the accelerator pedal

  the operator is stopped, this garage maneuvering mode can also

  Lement be deleted, that is to say that the predetermined speed of parking maneuver is exceeded. He is in

  in addition advantageous to observe the power of friction generated

  rée in the clutch 18 during this skating mode, to avoid overheating or overloading in particular in the case of dry friction clutches. So for example at

  using slip and clutch torque or even torque

  drive and temperature, by integrating these quantities as a function of time, we can determine the

  load applied to the clutch and this mode of maneuver

  rage, during which the clutch 18 is in slip mode, can then be suppressed by disengaging the clutch if

  it is detected that the clutch has been stressed too much.

  When the drive system 10 according to the

  vention is used on a sloping roadway, it is also

  ment possible, as will be described later,

  to prevent the vehicle from starting to roll accidentally-

  in a direction which does not correspond to the direction

  planned displacement. In this case, it is assumed that the drive unit 12 is operating, that a speed, in particular a starting speed (first gear, second gear or reverse) has shifted into the gearbox 24, which the driver first maintains depressed the brake pedal 58 to prevent the vehicle from rolling forcibly and

  moreover the accelerator pedal 56 is not yet action-

  born. If the driver now intentionally or unintentionally releases the brake pedal, in principle the vehicle could run in the unwanted direction, for example when moving.

  back. In this operating situation, we predict-

  mine in the control installation a set speed

  equal for example to zero km / h, which is ultimately a vi-

  tesse corresponding to the situation in which the conduct-

  teur does not operate the accelerator pedal 56. Under these conditions as soon as the vehicle begins to roll, the clutch 18 is controlled in the closing direction and if necessary at the same time the drive unit 12 can be controlled to increase the power supplied and again to prevent the clutch 18 from reducing the speed of rotation of the drive unit 12 and risking stalling, in particular in the case

  an internal combustion engine. We can use for this purpose

  also information concerning the load, the slope of the roadway and, if applicable, the grip coefficient of the

  pavement to control the restoring device

  power setting 36 independently of the type of engine, so that the speed of rotation of the motor unit 12 is kept within an appropriate range, for example in the range of the idle speed or slightly above this range. As in the case of the speed recording devices currently used, in particular the sensors are affected by certain inaccuracies of recording or of a limited resolution of the speed, which can be situated in a range going up to 0.8 km / h, instead of predetermining a set speed equal to zero km / h, it is also possible to predetermine a set speed other than zero km / h

  in the speed resolution range; in other words

  mes, a predetermined speed is predetermined which is for example around 0.8 km / h and corresponds to a direction in which the vehicle would move under normal driving conditions, with a speed ratio. This means that under these conditions, by regulating the position or the torque of the clutch 18, a speed of the vehicle is regulated over a

  value of minimum measurable speed, different from speed

  zero weight. By performing such a regulation operation,

  by partially opening the clutch 18, the speed is lowered

  vehicle size again to zero or

  within a range of 0.8 km / h so that ultimately the vehicle

  cule will not move continuously but each time there will be a brief rolling of the vehicle at a different speed

  from zero immediately followed by a stop or near stop.

  If the slope of the road is so steep

* as long as it is not possible to regulate the preset speed-

  completed taking into account the load possibility applicable to the clutch, under these conditions, for example in

  limiting the clutch torque to the maximum, the vehicle drives

  ra slowly backwards in the unwanted direction but

  with the braking effect provided for by the engagement at least par-

clutch.

  The load applied to the clutch can be deter-

  mine by monitoring the friction work carried out

  shot of the clutch torque and the difference in rotational speeds between input 16 and output 20 of the clutch. If the friction work or the friction power are too great or exceed a maximum authorized value, the clutch can be opened linearly, in stages, or in another way, by successive operations or / and

  lower the engine torque to avoid overloading the clutch, which is particularly important in the case of clutches

  dry friction. This security function can

  also be deleted when the vehicle starts to roll

  ler actually in the right direction or that the pedal

accelerator is activated.

  The two procedures described above allow the driver of a vehicle to maneuver it in particular

  in a very low speed range, acting in my-

  significantly simpler because, on the one hand, for garage maneuvers there will be a defined movement of the vehicle and, on the other hand, for travel on mountain roads, in particular at start-up, the driver will not have

  not have to go very quickly from the brake pedal to the

  accelerator pad to prevent the vehicle from rolling backwards; on the contrary, as soon as it releases the brake pedal, the intervention of the clutch system or the drive unit management system will actively prevent the vehicle from

accidentally rolls.

Claims (13)

R E V E N D I C A T I ON S   1) Method for controlling a compressed drive system   nant a drive unit (12), an automatic clutch (18) and   a gearbox (24), preferably an automatic gearbox   that (24), characterized in that a) it is detected whether the motor unit (12) is operating,   b) it is detected if a gear has shifted into the gearbox braids (24),   c) it detects to what extent an action installation   driving (56), preferably an accelerator pedal (56) has been actuated,   d) then, if it has been observed in step a) that the unit mo-   trice (12) works, in step b) that a report of   gear is shifted into the gearbox (24), from   refers to the starting speed, and in step c) that   the pipe actuation installation (56) has been ma-   new but with a lower degree of maneuver from the   at the option of actuating a garage maneuvering threshold,   controls the clutch (18) to set a gear speed   predetermined garage maneuvering sign.   2) Method according to claim 1, characterized in that   the drive unit (12) is also controlled to adjust the speed   garage maneuver instruction size.   3) Method according to claims 1 or 2,   characterized in that the clutch (18) or the drive unit (12) are not controlled to adjust the setpoint speed for garage operation, only   when the brake is not applied.   4) Method according to one of claims 1 to 3,   characterized in that the garage maneuver setpoint speed is a speed other than zero, situated in a range of up to Km / h, and preferably up to 3 Km / h.) Drive system comprising:   - a motor unit (12), connected or capable of being re-   linked by an automatic clutch (18) to a gearbox   braids (24), preferably an automatic gearbox   material (24) for producing a torque transmission link,   - a pipe actuation installation (56), pre-   gives an accelerator pedal (56) to control the drive unit (12) according to the degree of actuation for the torque to be supplied, - a speed input device (48, 50, 52, 54, 34), - a control installation (34) for controlling the drive unit (12) and / or the clutch (18), characterized in that   the control installation (34) controls the clutch for   set a preset garage maneuver speed   denies, if the drive unit (12) is used,   if a gear ratio, preferably the starting speed,   rage, has passed into the gearbox (24) and if the   pipe actuation unit (56) is actuated   before a degree other than zero, located below the degree   actuation of garage maneuvering instruction.   6) Drive system according to claim 5, characterized in that   the control system (34) also controls the mo-   to adjust the speed to the setpoint speed of garage laborer.   7) A method of controlling a drive system, this system   teme comprising a drive unit (12), an automatic clutch   tick (18) and a gearbox (24), preferably an automatic gearbox (24), characterized in that 3 a) it is detected if the power unit (12) is operating, b) it is detected if a gear ratio has gone into the gearbox (24), c) it is detected whether a driving actuation installation (56), preferably the accelerator pedal (56), has been actuated, d) then, if it has been detected in step a) that the power unit (12) operates, in step b) that a speed, preferably the starting speed, has passed into the gearbox (24), and in the step c) that the driving actuation installation (56) has not been actuated, the clutch installation (18) is controlled to adjust a   predetermined set speed.   8) Method according to claim 7, characterized in that the clutch (18) is controlled only if the speed deviates from zero km / h.   9) Method according to claims 7 or 8,   characterized in that the set speed is a speed of zero km / h, or a speed other than zero km / h in the speed resolution range of a speed input device (48, 50, 52,   54, 34) in the direction predetermined by the gear ratio past tesse.   10) Method according to one of claims 7 to 9, characterized in that   the drive unit (12) is also controlled to adjust the speed target size.   11) Drive system comprising: - a drive unit (12) which can be connected to the torque transmission by means of a clutch   automatic (18), a gearbox (24), preferably   an automatic gearbox (24),   - a pipe actuation installation (56), pre-   refers to an accelerator pedal (56), which controls the drive unit (12) to supply the torque according to the degree of actuation of this pedal, - a speed input device (48, 50, 52, 54, 34 ), - a control installation (34) for controlling the drive unit (12) and / or the clutch (18), characterized in that the control installation (34) actuates the clutch (18) to adjust a set speed if the drive unit (12) is started, if a gear ratio, preferably the starting speed, has shifted into the gearbox (24) and if the driving actuation installation (56) has not been activated.   ) Drive system according to claim 11, characterized in that   the set speed is fixed at zero km / h.   13) Drive system according to claim 11, characterized in that the target speed is a speed located in the speed resolution range of the speed input device (48, 50, 52, 54, 34) in which the direction provided for the past gear ratio is a speed different from zero km / h.   14) Drive system according to one of claims 11 at 13, characterized in that   the control installation (34) also activates the mo-   trice (12) to set the target speed.   15) Drive system according to one of claims 11   to 14, characterized in that the control installation (34) actuates the clutch (18) or / and the drive unit (12) to adjust the set speed   only if the brake is not applied.