FR2772095A1 - CLUTCH CONTROL METHOD - Google Patents

Abstract

There is provided a clutch control method for reducing a shock or impact occurring due to a change in vehicle acceleration upon disengaging / engaging a clutch (30). The clutch control method includes the steps of controlling an output of an engine to reduce engine torque transmitted from an output shaft (11) of the engine (10) to an input shaft (21) of the transmission (20) via the clutch (30) to a preset value decided by the engine torque and a speed ratio at the moment when the gear change was requested when the demand to change the gear of the transmission is detected from so that a first inflection point occurs when the vehicle acceleration is nearly zero in a vehicle acceleration fluctuation characteristic curve obtained by controlling the engine output; and fully disengaging the clutch by a clutch control member (A3) after maintaining control of the output of the engine for a preset time so that the fluctuation in vehicle acceleration occurring thereafter converges to neighborhood of almost zero value.

Description

CLUTCH CONTROL METHOD

  The present invention relates to a method of

  clutch control used to control clutch release and clutch operations (dry clutch) which

  is interposed between an output shaft of a motor of a vehicle

  hicle and an input shaft of a transmission and which ac-

  torque / uncouples the transmission of the torque corresponding to a drive state by the use of a

clutch control.

  It is described, for example, in the document JP-A-2-

  229922 a method of controlling a clutch. In accordance with a control method described in the publication, it adopts steps consisting in adjusting a clutch coupling speed at start-up corresponding to

  engine speed and a gear change ratio

  it and the step of performing a clutch coupling operation at the clutch coupling speed. It also provides for a stage consisting of

  perform a clutch declutching operation when

  that an accelerator is placed in the inactive state and that the

  vehicle size drops below a predetermined speed

finished.

  The clutch control method described in the

  previously mentioned, is made up of processes allowing the clutch to be fully disengaged when

  the accelerator is not depressed and the vehicle speed

  This drops below the predetermined speed to prevent the engine from stopping and to prevent a drop in engine speed and a jerk during the clutch engagement operation. However, it does not take into account an impact or shock caused by the change of

  vehicle acceleration during the dismantling operation

  clutch / clutch clutch and it is possible that a

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  shock or impact of great value may occur during

  the clutch disengage / clutch operation.

  As such, the significant shock or impact caused by the change in vehicle acceleration during the clutch release / clutch operation occurs due to the resonance of a drive train system when declutch / clutch operation

  of the clutch is driven when the vehicle

  decelerates / decelerates in a situation where a drive shaft (propulsion shaft) extending from an output shaft of a transmission to a rear differential is long and the rigidity of the drive train system

  the clutch to the tires is insufficient such as in a vehicle

hicule FR.

  It is an object of the present invention to provide a

  process which lessens the change in acceleration of the vehicle

  which leads to the shock or impact described above.

  In accordance with a first aspect of the invention,

  a clutch control method for controlling the operations

  clutch release and clutch rations that are interposed between an engine output shaft and a shaft

  input of a vehicle transmission and which deliver

  ple / uncouples the transmission of a torque corresponding to a driving state using a clutch control member, includes the steps of controlling an engine output to reduce the engine torque transmitted from the engine output shaft to the input tree of the

  transmission via the clutch to a preset preset value

  given by the engine torque and at a speed ratio at the

  where the gear change was requested, when the

  request to change the transmission speed is de-

  tected, so that a first inflection point occurs when the vehicle acceleration is almost zero in a characteristic curve of the fluctuations in vehicle acceleration obtained by controlling the output

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  of the motor; and fully disengage the clutch by the clutch control member, after having maintained

  control of the motor output for a preset time

  bli so that the fluctuation in the acceleration of the vehicle

  cule occurring thereafter converges in the vicinity of a

value almost equal to zero.

  In accordance with a second aspect of the invention, a

  clutch control method for controlling operations

  declutching and clutching of a clutch which is interposed between an output shaft of an engine and a shaft

  vehicle transmission input and which deliver

  ple / uncouples the torque transmission corresponding to a driving state using a clutch control member, comprises the steps consisting in: placing the clutch from a fully disengaged state to a state half engaged by the clutch control to increase the input torque transmitted from the engine output shaft to the transmission input shaft

  via the clutch to a preset value decided by the vi-

  vehicle size and a gear ratio when the gear change is complete, when the gear change

  transmission speed is detected, so that a pre-

  mier inflection point occurs at the preset value in a characteristic curve of the fluctuations of

  vehicle acceleration obtained by half state

  engaged; and fully engaging the clutch after maintaining the half-engaged state for a preset time so that the fluctuation in vehicle acceleration occurring thereafter converges in the vicinity of the value

preset.

  The method of the first aspect of the invention allows the acceleration of the vehicle to converge in the vicinity of a value almost equal to zero after having changed the acceleration of the vehicle from the value when the change in speed was requested to almost worth

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  equal to zero during the preset time, disengaging the clutch so that it allows the change in vehicle acceleration, which occurs during

  the clutch release operation is minimized and shortened

  temporarily shortened, and the shock or impact occurring

  during the clutch release operation is re-

  duit. Thus, the inventive process can provide a sense of

  comfortable driving, less sensitive to shocks or

  impacts, without shortening the duration of the

clutch and clutch.

  Furthermore, the method of the second aspect of the invention allows the acceleration of the vehicle to be brought to converge in the vicinity of a preset value after

  having changed the acceleration of the vehicle from the

  their when the gear change is completed at the

  their preset for the preset time in the clutch of the clutch, so that it allows the change in vehicle acceleration, which occurs

  during the clutch engagement operation, i.e. mini

  bet and shortened temporarily and the shock or impact occurring during the clutch engagement operation is reduced. Thus, the inventive method can also provide the feeling of comfortable driving less sensitive to shocks, while shortening the duration of the clutch operation of the clutch. Shortening the duration of the clutch clutch operation allows the duration of the half-clutched state to be shortened and the life of the clutch to be extended. The duration of the clutch declutching operation and the duration of the clutch clutch operation can both be shortened and the total time required

  to change the transmission speeds can be reduced

  shortened by performing both the first and second aspects of the invention. It thus allows the feeling of free running of the vehicle to be reduced, that the feeling of

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  direct steering is improved and the feeling of

  handling and control stability are improved.

  The specific nature of the invention, as well as

  other purposes, uses and benefits thereof, appear

  will be clear from the following description and

  from the accompanying drawings on which references

  Identical numerals refer to identical parts.

  Figure 1 is a simplified diagram of a first mode

  of embodiment in which the present invention is applied

  for a vehicle fitted with a gearbox and automatic clutch system;

  FIG. 2 is a diagram showing a configuration

  gear change and transmission

felt in Figure 1;

  FIG. 3 is a diagram of the hydraulic circuit shown

  trant the detailed structure of a clutch control member shown in Figure 1;

  Figure 4 is a flow diagram of a training program.

  command executed by the electronic control unit shown

  felt in Figure 1; Figure 5 is a flowchart showing a program

  clutch disengagement control when a change-

  speed is required, as shown in Figure 4; Figure 6 is a flowchart showing a program

  clutch control when the clutch changes

  speed is completed, as shown in Figure 4;

  FIG. 7 is a graph of the characteristic curves

  showing the characteristics of change in vehicle acceleration, engine torque and shafts

  input and output of the transmission, obtained in exe

  cutting the clutch release clutch control program when the gear change is required, as shown in Figures 4 and 5;

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  FIG. 8 is a graph of the characteristic curves

  ques, corresponding to Figure 7, when a pre-

  engine torque is set at 60% of that at mo

  ment where the gear change was required and that a preset time is fixed at 200 msec .;

  FIG. 9 is a graph of the characteristic curves

  ques, corresponding to figure 7, when the value pre-

  engine torque has been set at 30% of that at least

  ment where the gear change was required and that the preset time is fixed at 200 msec .;

  FIG. 10 is a graph of the characteristic curves

  ticks, corresponding to figure 7, when the value pre-

  engine torque is set at 45% of that at mo

  ment where the gear change was required and the preset time is fixed at 200 msec .;

  FIG. 11 is a graph of the characteristic curves

  ticks, corresponding to figure 7, when the value pre-

  engine torque is set at 45% of that at mo

  ment where the gear change was required and the preset time is fixed at 50 msec .;

  FIG. 12 is a graph of the characteristic curves

  ticks, corresponding to figure 7, when the value pre-

  engine torque is set at 45% of that at time

  o the gear change is required and the pre-set time

bli is set at 150 msec .;

  FIG. 13 is a graph of the characteristic curves

  ticks showing changes in vehicle acceleration, engine torque and shafts

  input and output of the transmission, obtained in exe

  cutting the clutch control program of the clutch when the gear change is complete, as shown in Figures 4 and 6;

  FIG. 14 is a graph of the characteristic curves

  ticks, corresponding to figure 13, when a pre-established value of the half-engaged couples is established at 75% of the

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  input torque after completion of clutch clutch

  clutch and that a preset time is fixed at 200 msec;

  FIG. 15 is a graph of the characteristic curves

  ticks, corresponding to figure 13, when the value pre-

  established half-engaged torque is established at 30% of the input torque after completion of the clutch of the clutch and that the preset time is fixed at 200 m / seconds;

  FIG. 16 is a graph of the characteristic curves

  ticks, corresponding to figure 13, when the value

  preset of the half-engaged torque is established at 58% of

  input pl after completion of the clutch of the em-

  clutch and that the preset time is fixed at 200 msec;

  FIG. 17 is a graph of the characteristic curves

  ticks, corresponding to FIG. 13, when the preset value of the half-clutch torque is fixed at 58% of the input torque after the clutch clutch has been completed and the preset time is fixed at 50 msec;

  FIG. 18 is a graph of the characteristic curves

  ticks, corresponding to figure 13, when the value

  preset half-clutch torque is established at 58% of the

  input pl after completion of the clutch of the em-

  clutch and that the preset time is fixed at 150 msec; Figure 19 is a simplified diagram of a second mode

  of embodiment in which the present invention is applied

  than a vehicle fitted with a gearbox system

  automatic and automatic clutch;

  Figure 20 is a diagram showing the relationship between-

  be a gear shift lever, a shift button

  speed control and a speed change load switch shown in Figure 19; Figure 21 is a flow diagram of a

  command executed by the electronic control unit re-

  shown in Figure 19; Figure 22 is a flowchart showing a program

  clutch disengagement control when a change-

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  speed is required as shown in Figure 21; and Figure 23 is a flowchart showing a program

  clutch control when the clutch changes

  speed is completed as shown in the

figure 21.

  Preferred embodiments of the present in-

  vention will be explained below with reference to the-

  sins. Figures 1 to 6 show a first embodiment

  sation (in which the present invention is applied to

  a vehicle fitted with a gearbox and gearbox system

  automatic clutch) of the invention. In the first mode

  embodiment, a dry clutch 30 for coupling / deactivation

  couple the torque transmission is interposed between an output shaft (crankshaft) 11 of an engine 10 and a shaft

  input 21 of a transmission 20, as shown

  tee in a simplified way on figure 1. A tree of exit

  tie 22 of transmission 20 is also coupled to a

  rear wheel 44 so as to be capable of transmitting the

  ple via a propulsion shaft 41, a rear differential 42 and a rear axle or axle 43. A speed sensor

  Si 110 wheel fitted corresponding to the rear wheel 44

  tects the speed of the SPD vehicle and enters it in a

  electronic control unit UCE.

  A throttle actuator A1 controls an output

  tie of the engine 10 and a crankshaft angle sensor S2 detects a number of rotations (engine speed) Ne of the output shaft 11 thereof and between it in

  the UCE electronic control unit. A papil sensor

  lon S3 detects an opening angle (throttle opening) O of a throttle valve 12 and between it in the electronic control unit UCE. The controller

  of the butterfly A1 controls the opening of the throttle valve

  regulation 12 under the control of the electro-

  ECU picnic. Note that the throttle valve 12

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  is open / closed also in connection with the control of an accelerator pedal (not shown) activated by a driver. The transmission 20 is a transmission comprising 5 forward gear ratios and a reverse gear and gear (gear position 1 to 5 and R, gear configuration shown in FIG. 2) and is arranged in such a way that a shaft d a shift and selection lever 24 is moved by a control member

  gearbox change A2 in conjunction with the

  control of a gear lever 23 activated by the driver.

  A gear lever sensor S4 detects the speed control position SPI of the gear lever 23 and enters

  this in the UCE electronic control unit. A Cape-

  speed selector switch S5 detects the position of

  the speed operation SPo of the selector lever shaft

  tion and gear change 24 and between it in the electronic control unit UCE. The gearshift control member A2 drives the lever lever shaft.

  selection at a shift 24 so that the po-

  SP0 functional position coincides with the po-

  SPI shift control under the

  control of the UCE electronic control unit.

  The clutch 30 itself is a dry clutch with only one

  friction disc which deactivates the transmission of the

  ple by tilting a clutch uncoupling fork

  31 in the declutching position (disengaging operation

  clutch) and which allows the transmission of torque in inclination

  lifting (bringing back) the uncoupling fork of the em-

  clutch 31 in the clutch position (clutch operation

  clutch). A clutch control member A3 controls the clutch release and clutch operations 30 corresponding to the driving state. An S6 clutch stroke sensor detects the tilt position of the

  clutch fork 31, i.e. a travel of

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  CRCST clutch and between it in the control unit

ECU electronics.

  As shown in detail in Figure 3, the clutch control member A3 includes a clutch decoupling cylinder 51 for pushing the clutch decoupling fork 31 to the disengaged position.

  while resisting a clutch spring 32 (see fig.

  gure 1), a control valve 52 for controlling the pressure

  oil delivered to / discharged from the cylinder

  clutch uncoupling 51, an accumulator 53 for. ac-

  accumulate the pressurized oil supplied to the pressure relief valve

  request 52, a pressure switch 54 which is closed

  when the hydraulic pressure inside the accumulator

  lator 53 is equal to or greater than a preset value,

  a motor pump 57 for sucking the engine oil from the

  servoir 55 for discharging to the accumulator 53 via a

  non-return valve 56 in order to maintain the hy-

  hydraulics inside the accumulator 53 at a pressure equal to or higher than the preset value and a valve

  58 to prevent hydraulic pressure at the inside

  of the accumulator 53 to rise abnormally

  male. The electronic control unit UCE controls the operation of the control valve 52. The electric control unit UCE also controls the drive of the engine pump 57 when the ignition switch IG (see Figure 1) is CLOSED and when the switch

  pressure 54 is OPEN. When the ignition switch

  mage is CLOSED, the hydraulic pressure inside

  the accumulator 53 is kept at a pressure equal to or above

  lower than the preset value.

  The UCE electronic control unit controls the operations

  rations of the throttle control member A1, the shift control member A2 and the shift member

  clutch control A3. It consists of a micro-

  computer, or the like, containing a timer and it executes a control program according to the flowcharts represented in FIGS. 4 to 6 on the basis of the respective signals (vehicle speed SPD, engine speed at Ne, throttle opening angle 0 , SPI gear shift control position, SPO gear shift functional position and CRCST clutch stroke)

  detected by the respective sensors S1 to S6, described below

  above and in the CLOSED / OPEN state or a CLOSED signal from the

  IG ignition switch.

  We will now describe the operation of the first

  embodiment by referring to the flowcharts represented

  shown in Figures 4 to 6. The electro-

  nique UCE begins to execute the program in a step 101 when the ignition switch IG is (manipulated from the open state to the CLOSED state). It then initializes the program in a step 102, performs the input processing of the respective detected signals (vehicle speed SPD,

  engine speed Ne, throttle opening angle 0, po-

  SPI shift control position, position

* functional SPo gear change and gear travel

  clutch CRCST) from the respective sensors S1 to S6, and from the CLOSED / OPEN state or from an active signal from the ignition switch IG starter in step 103, selects a clutch control mode Cmode in a step S104 and executes the respective steps 105 to 113 corresponding to the respective clutch control modes, Cmode = 0 to Cmode = 8. It should be noted that the electronic control unit UCE performs various failure treatments

  in step 114 and returns to step 103 after having executed

  t each of steps 105 to 112. The electronic control unit

  Tonic UCE repeats the processing to execute steps 103 to 114 in a predetermined period of 4 msec. UCE electronic control unit finishes program execution

  in step 115 after performing step 113.

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  Step 105 is a clutch control program

  of the clutch when starting the engine which is run when

  that the clutch control mode Cmode = 0 is selected

  tiated in step 104. The clutch control mode Cmode = 0 is selected under the condition where the vehicle speed SPD and the engine speed Ne are equal to 0, that the stroke of the CRSCT clutch is equal or lower

  to a predetermined value (clutch clutch state)

  clutch), the SPI gear change control position and the SPE gear shift functional position are both Neutral or Reverse and the ignition switch starter

  IG is CLOSED The contents of the command executed at this time

  consist in bringing the control member of the em-

  clutch A3 to quickly perform a shift operation

  clutch to quickly and fully disengage the clutch

  (by delivering the oil under pressure to the pressure cylinder

  clutch clutch 51 from accumulator 53 via

  the control valve 52) after checking that the pressure

  oil inside the accumulator 53 is equal to or greater than the value preset by a signal

  detected from pressure switch 54 and ac-

  activating a starter motor not shown to activate the engine 10 when the clutch 30 is fully disengaged. It should be noted that when the hydraulic pressure inside the accumulator 53 is lower than the preset value, the control valve 52 does not operate until the hydraulic pressure inside

  accumulator 53 is increased to become equal or greater

  lower than the preset value by driving the motor pump

author 57.

  Step 106 is a program for controlling clutch disengagement while the engine is idling (the vehicle is stopped) which is executed when the clutch control mode Cmode = 1 is selected at

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  step 104. The clutch control mode Cmode = 1 is selected under the condition o vehicle speed

  SPD is equal to or less than the predetermined value in-

  cluting a value equal to 0, the motor speed Ne is equal to or less than the predetermined value which is not

  equal to 0, the stroke of the CRCST clutch is equal to or greater than

  less than the predetermined value (the clutch is total-

  disengaged), the gear change control position

  tesse SPI coincides with the functional position of life

  tesse SP0 and the opening angle of the butterfly 0 is equal to or less than the predetermined value. The contents of the

  command executed at this time consists in maintaining the

  clutch control lever A3 in the declutching functional state in order to keep the clutch 30 in the fully state

disengaged.

  Step 107 is a program for controlling clutch disengage during start-up which is executed when the clutch control mode Cmode = 2

  is selected in step 104. The command mode of the em-

  clutch Cmode = 2 is selected under the condition where the vehicle speed SPD is equal to or less than the predetermined value including a value equal to zero, the speed

  motor Ne is equal to or less than the predetermined value

  mined which is not equal to zero, the stroke of the CRCST clutch is equal to or greater than the predetermined value

  (the clutch is fully disengaged), the position of com-

  SPI gear change command and function position-

  SPO gearshifts are any of the First to Fifth or Reverse gears

  and SPI É SP0. The contents of the command executed at this time

  consist in maintaining the control member of the em-

  clutch A3 in the declutching functional state to maintain the clutch 30 in the fully disengaged position. In addition, the electronic control unit UCE attacks the

  shift control A2 to bring the position

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  SPO functional gear shifting to coincide

  with the SPI shift control position.

  Step 108 is a clutch control program for the clutch at start-up which is executed when the clutch control mode Cmode = 3 is selected in step 104. The clutch control mode Cmode = 3 is selected under the condition where the speed of the SPD vehicle is equal to or less than the predetermined value including

  the value 0, the motor speed Ne is equal or less

  greater than the predetermined value which is not equal to zero, the stroke of the CRCST clutch is equal to or greater

  at the determined value (the clutch is completely de-

  crossed out), the SPI shift control position and the SPO speed functional position are all

  both at any of the Pre-

  to Fifth or reverse (when the SPO speed shift position coincides with the SPI shift control position being driven by

  the speed change control unit A2) and the an-

  gle of opening of the butterfly 0 is equal to or greater than the predetermined value). The contents of the command executed at this time consist in causing the clutch control member A3 to progressively perform the operation

  clutch to engage clutch 30 at a pre-

determined.

  Step 109 is a hold control program

  clutch clutch during normal driving

  poorly executed when the clutch control mode

  Cmode = 4 is selected in step S104. the mode of

  clutch command Cmode = 4 is selected in the condition

  tion o the vehicle speed SPD and the engine speed Ne are equal to or greater than the predetermined values, the stroke of the CRCST clutch is equal to or less than the predetermined value (clutch clutch condition) and the position of SPI shift control and the

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  functional position of the SPO gear ratio are all

  both of them at any of the First to Fifth or reverse gears. The contents of the

  command executed at this time consists in maintaining the em-

  clutch 30 in fully engaged state without actuating the

clutch control valve A3.

  Step 110 is a clutch disengagement control program when a gear change (gear change required) which is executed when the clutch control mode Cmode = 5 is selected in step 104 The clutch control mode Cmode = 5 is selected under the condition where the vehicle speed SPD and the engine speed Ne are equal to or greater than the predetermined values, the clutch stroke CRCST is

  equal to or less than the predetermined value (state of em-

  clutch clutch) and the shift control position

  SPI speed control and the functional position

  SPO gear port are any of the First to Fifth gear or reverse and SPI gear ratios

  SPO. The contents of the command executed at that time are

  will be described later with reference to the organization chart

shown in Figure 5.

  Step 111 is a clutch control program for the clutch when the gear change is complete which is executed when the clutch control mode Cmode = 6 is selected in step 104. clutch control Cmode = 6 is selected under the condition o the vehicle speed SPD and the speed of the

  NE motor are equal to or greater than the predeter-

  the CRCST clutch stroke is equal to or greater than

  less than the predetermined value (the clutch is complete-

  disengaged) and the shift control position

  SPI gear ratio and functional position of report

  SPI speed port are both at any one

  First to Fifth gear or reverse gear

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  laugh. The contents of the command executed at that time are

  ront described below with reference to the flowchart shown in Figure 6. Step 112 is a clutch release clutch control program when the vehicle is stopped which is executed when the control mode of clutch Cmode = 7 is se-

  selected in step 104. The clutch control mode Cmode = 7 is selected under the condition where the vehicle speed SPD and the engine speed Ne are equal to or less than the predetermined values which are not equal.

  at zero, the stroke of the CRCST clutch is equal or equal

  lower than the predetermined value (the clutch is

  crossed out) and the butterfly opening angle 0 is equal or equal

  lower than the predetermined value. The contents of the

  command executed at this time consist in causing the clutch control member A3 to progressively carry out the clutch release operation at a predetermined speed for

  fully disengage clutch 30 at the predetermined speed

  born. Step 113 is a program for controlling the clutch of the clutch when the engine is stopped, which is executed

  when the clutch control mode Cmode = 8 is se-

  selected in step 104. The clutch control mode Cmode = 8 is selected under the condition where the vehicle speed SPD and the engine speed Ne are equal to

  zero and that the stroke of the CRCST clutch is equal or greater

  less than the predetermined value (the clutch is total-

  disengaged) and when a predetermined period has elapsed

  after the IG ignition switch has been OPEN.

  The contents of the command executed at this time consist in causing the clutch control member A3 to perform

  the clutch operation for engaging the clutch 30.

  Now the clutch declutch control program, when a gear change is required, will be explained with reference to the flow diagram shown

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  in Figure 5. The UCE electronic control unit cal-

  calculates the engine torque T on the basis of the engine speed Ne, the throttle opening angle 0 entered in step

  103 in FIG. 4 and with reference to a table of corres-

  engine torque weight (stored in advance in the electronic control unit UCE), calculates a motor torque of

  first order delay Te from it via wire-

  tre and stores it as a fixed torque in step 201.

  Then, a branch corresponding to a value of an engine torque control indicator TF is selected in step 202. The electronic control unit UCE performs steps 203, 204, 205, 206 and 207 when the branch "O "

  (mode for calculating a preset value and a preset duration

  engine torque) is selected, performs steps 208, 209, 210 and 207 when branch "1" (mode for transferring the preset value of engine torque) is selected, performs steps 211, 212, 213, 214 and 207

  when the branch "2" (mode to maintain the torque mo-

  at the preset value for the preset duration) is selected and performs steps 215, 216 and 207 when branch "3" (clutch disengaging operation mode

clutch) is selected.

  In step 203, the electronic control unit UCE calculates and stores a time for fixing and maintaining engine torque tfe based on the functional position of speed ratio SPO entered in step 103 in FIG. 4 and the torque motor (fixed torque Te) calculated and memorized in step 201 and by reference to a correlation table for fixing and maintaining motor torque time (which has been obtained on the basis of various experiments and analyzes and is memorized in the UCE electronic control unit

  in advance). In step 204, the electronic control unit

  that UCE calculates and stores a target motor torque Ti based on the speed of the motor Ne and the functional position of speed ratio SPO entered in step 103 in FIG. 4

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  and the calculated engine torque Te is stored in step 201 and by reference to a torque correspondence table

  target engine (which was obtained on the basis of various ex-

  experiences and analyzes and stored in advance in the electronic control unit UCE). In step 205, the electronic control unit UCE calculates and stores a target throttle opening angle Oi to adjust the output torque of the engine 10 to the target engine torque Ti calculated and stored in step 204 on the basis of the motor speed Ne and by reference to a torque correspondence table

  motor (which is stored in advance in the control unit

  electronic control unit). In step 206, the electronic control unit UCE passes the value "0" of the switch TF

  which was initialized in step 102 in Figure 4 at "1".

  Then, the electronic control unit UCE controls the drive of the throttle control member A1 so as to fix the opening angle of the throttle 0 at the angle

  opening the target butterfly Oi in step 207.

  In step 208, the electronic control unit UCE calculates and stores an opening difference 0e between

  the target throttle opening angle Oi and the opening angle

  current butterfly vertex 0. It then determines whether or not the absolute value of the aperture difference

  Oe is less than a preset value Oel in step 209.

  It passes the value "1" of the switch Tf which has been mo-

  defined in step 206 to "2", in step 210. It should be noted that the execution of steps 208, 209, and 207 means that the throttle controller A1 controls the angle

  butterfly opening 0 by feedback.

  The UCE electronic control unit processes

  subtraction during the time of fixing and maintaining the engine torque tfe calculated and stored at

  step 203 and stores the result in step 211. It de-

  then ends whether or not the duration of fixing and maintaining the engine torque tfe memorized in step 211 is

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  equal to or greater than zero. The electronic control unit

  that UCE passes the value "2" of the TF indicator which has been

  modified in step 210 to "3" in step 213. The control unit

  electronic control unit UCE also calculates an opening angle

  engine speed-keeping throttle valve whereby engine speed will not increase even when clutch is disengaged based on engine speed

  Ne, changes the target butterfly opening angle Oi to this

  it and stores this value. It should be noted that

  performing steps 211, 212, and 207 means that the du-

  preset value of the target motor torque Ti is maintained.

  The UCE electronic control unit controls the

  dragging of the clutch control member A3 in order to completely disengage the clutch 30 in step 215. It then passes the value "3" of the indicator TF which has been

  changed in step 214 to "0" in step 216.

  In this regard, the execution of steps 201 to 216, in FIG. 5 described above, allows the engine torque T to be reduced to the preset value (the calculated value

  is memorized in step 215, for example 45% of the torque

  tor T at time a) Ti by modifying the butterfly opening angle 0 to the target butterfly opening angle Oi which

  sets the output (motor torque) of motor 10 to the minimum torque

  target tor Ti at time a (when the change in vi-

  size is required) before clutch 30 is fully

  disengaged and therefore allows a first point of in-

  bending P1 in a characteristic fluctuation curve

  vehicle acceleration to occur when the ac-

  vehicle celerity is almost zero and the flux

  acceleration of the vehicle which occurs through the

  or be brought to converge near a value near-

  that equal to zero by completely disengaging the clutch 30 thanks to the clutch control member A3 after having

  maintained control of the motor output during the

  preset time (the duration calculated and stored in step

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  203, for example 95 msec) tfe as shown on the

figure 7.

  Consequently, since the inventive method allows the acceleration of the vehicle to be brought to converge in the vicinity of a value almost equal to zero after changing the acceleration of the vehicle from the value o the change in speed has been required (instant a) at a value almost equal to zero during the preset time tfe when the clutch is disengaged 30 when the gear change of the transmission 20 is required, this allows the change in acceleration of the vehicle, which occurs during the clutch release operation, is minimized and shortened temporarily and that the shock or impact occurring during the clutch release operation is reduced. Thus, the inventive method can

  provide a less sensitive comfortable driving feeling

  ble to shocks while shortening the duration of the operation

clutch disengagement.

  Note that Figures 8 to 12 show the re-

  experimental and analytical characteristic results set

  opens in advance, to find (to get the characters-

  shown in figure 7) the pre-set value

  optimal blie Ti of the engine torque T and the pre-set duration

  blie optimal tfe, in which figure 8 shows the re-

  result when the preset value Ti of the engine torque T is fixed at 60% of this at the time when the gear change is required and the preset duration tfe is fixed at msec (a positive residue remains in the acceleration of the vehicle), FIG. 9 shows the result when the preset value Ti of the engine torque T is fixed at 30% of the torque at the moment when the gear change is required and the preset time Tf is fixed at 200 msec (a negative residue remains in the vehicle acceleration), Figure 10 shows

  the result when the preset value Ti of the torque mo-

  tor T is set at 45% of the engine torque at the time when the

21 2772095

  gear change was required and preset time

  Tf is fixed at 200 msec (a residue from the acceleration of the

  hicule is made equal to zero), figure 11 shows the re-

  result when the preset value Ti of the engine torque T is fixed at 45% of the engine torque at the moment when the gear change was required and the preset time tfe is

  fixed at 50 msec. (Jolts remain during acceleration

  vehicle) and Figure 12 shows the result when

  that the preset value Ti of the engine torque T is fixed at 45% of the engine torque at the moment the gear change was requested and the preset time tfe is fixed 150 msec

  (jolts remain when accelerating the vehicle).

  Then, the clutch clutch control program

  clutch when the gear change is completed will be explained with reference to the flowchart shown in Figure 6. The electronic control unit UCE executes a motor speed control program (a control program for driving the gear unit throttle control Al so as to maintain the engine speed Ne just before the gear change) to set the engine speeds Ne regardless of the load during and after clutching

in step 301 in FIG. 6.

  Then, a branch corresponding to a value of

  the clutch torque control indicator CF is se-

  selected in step 302. The electronic control unit UCE performs steps 303, 304, 305, 306 and 307 when the

  branch "0" (mode for calculating a half torque value

  target engagement and a half hold and hold time

  clutch is selected), execute steps 308, 309, 310, 311 and 307 when the branch "1" (mode for transfer

  in the half-engaged state) is selected, performs the

  pes, 312, 313, 314 and 307 when the branch "2" (mode to maintain the half-engaged state) is selected and performs steps 315, 316 and 307, when the branch "3" (mode

  to fully engage the clutch) is selected.

22 2772095

  In step 303, the electronic control unit UCE calculates and stores the input torque To necessary to obtain the engine speed Ne and the vehicle speed SPD when the clutch 30 is fully engaged on the basis of the speed of the engine Ne, of the functional position of the speed ratio SP0 (or the speed change control position SPI) and of the speed of the vehicle SPD entered in step 103 in FIG. 4 and with reference to

  an input torque correspondence table (which is

  moralized in advance in the electronic control unit UCE). In step 304, the electronic control unit UCE calculates and stores a target half-clutch torque Th on the basis of the input torque To calculated and stored in step

  303 and by reference to a correspondence table of

  ple half clutched target (which has been obtained on the basis of various experiments and analyzes and is stored in advance in the electronic control unit UCE). In step 305, the electronic control unit UCE calculates and stores a target clutch stroke CRCSTi based on the target half-clutch torque Th calculated and stored in step 304 and by reference to a stroke match table target clutch (which was obtained on the basis of various experiences and analyzes and which is stored in advance in the electronic control unit UCE). AT

  step 306, the electronic control unit passes the

  their "0" of the indicator CF which was initialized in step 102 in FIG. 4 to "1". Then the control unit

  electronic controls the drive of the control unit

  clutch clutch A3 so as to fix the clutch stroke

  CRCST at the target clutch stroke CRCSTi in step 307.

  In step 308, the electronic control unit UCE calculates and stores a difference in stroke STe between the

  travel of the target clutch CRCSTi and the travel of the em-

  current CRCST clutch. It then determines whether or not

  the absolute value of the stroke difference STe is less

23 2772095

  less than a preset value STea in step 309. In step 310, the electronic control unit UCE calculates and stores a duration for fixing and maintaining half-engaged torque tfc on the basis of the functional position of gear SPO speed input in step 103 and TO input torque stored in step 303 and by reference to a correspondence table of duration of fixation and maintenance of

  half-clutched torque (which was obtained on the basis of di-

  for experiments and analyzes and which is stored in advance in the UCE electronic control unit). It changes the value "1" of the indicator CF which was modified in step 306 to "2" in step 311. It should be noted that

  performing steps 308, 309 and 307 means that the

  clutch control lever A3 controls the stroke of

  CRCST clutch against feedback.

  The UCE electronic control unit processes

  subtraction frame during the half-clutch torque hold fastening time tfc calculated and stored at

  step 310 and stores the result in step 312. It

  then ends whether or not the duration of fixing and holding the half-clutch torque memorized in step 312 is equal to or less than zero in step 313. The electronic control unit UCE passes the value "2 "from the CF flag which was changed in step 311 to" 3 "in step 314. It should be noted that the execution of steps 312, 313, and

  307 means that the preset duration of the job run

CRCSTi target clutch is maintained.

  The UCE electronic control unit controls the

  dragging of the control member A3 in order to fully engage

  the clutch in step 315. It then passes the

  their "3" of the CF indicator which was modified in step

* 314, at "0" in step 316.

  In this regard, the execution of steps 301 to 316 on the

  figure 6 described above allows that allows a point of in-

  bending P2 occurs at the preset value in a

24 2772095

  characteristic curve of the fluctuations in vehicle acceleration obtained by the half-engaged state by placing the clutch 30 from the fully disengaged state to the half-disengaged state by the clutch control member A3 so to increase the input torque which is transmitted from the output shaft 11 of the motor 10 to the input shaft 21 of the transmission 20 to the predetermined value (the value calculated and stored in step 304, by example 58% of the input torque To calculated and stored in step 303) Th decided by the vehicle speed and the speed ratio

  when the completion of the transmission gear ratio-

  sion 20 is detected (at time b) and allows fluctua-

  tion of the acceleration of the vehicle subsequently occurring to be brought to converge in the vicinity of the value

  preset by fully engaging the clutch 30 by the or-

  clutch control handle A3 after maintaining the half-engaged state for the preset time (the time calculated and stored in step 310, for example 95 msec) tfc, as

  it is shown in figure 13.

  Consequently, since the inventive method allows the acceleration of the vehicle to be brought to converge at the

  near the preset value after changing the ac-

  vehicle celerity of a value almost equal to zero when the gear change is completed to the value

  preset during the preset time tfc when em-

  clutch 30 when the gear change of the transmission

  sion 20 is complete, this allows the change of ac-

  vehicle acceleration occurring during operation

  clutch clutch is minimized and shortened tem-

  porally and that the shock or impact occurring during the clutch engagement operation is reduced. Thus, the inventive method can provide a driving sensation

  comfortable with fewer shocks or impacts while reducing

  shortening the duration of the clutch clutch operation

  clutch. Shortening the duration of the operation

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  clutch, in turn, allows the duration of the half-engaged state to be shortened and the duration of

  clutch life 30 is extended.

  It should be noted that Figures 14 to 18 show the results of experiments and characteristic analyzes put

  in advance to find (obtain the characteristics

  ques shown in Figure 13), the optimal preset value Th of the half-engaged torque and the optimal preset duration tfc, in which Figure 14 shows the result when the preset value Th of the half-engaged couple. is set at 75% of To and the preset time tfc is set at 200 msec (a positive residue remains in the acceleration of the vehicle), Figure 15 shows the result when the preset value Th of the half-engaged torque is fixed at 30% of To and that the preset duration tfc is fixed at 200

  msec (a negative residue remains in the acceleration of the

  figure 16) shows the result when the preset value Th of the half-engaged torque is set at 58% of To

  and that the preset duration tfc is fixed at 200 msec (a re-

  vehicle acceleration is made equal to zero),

  Figure 17 shows the result when the value pre-

  established Th of the duration of the half-engaged torque is fixed at 58% of To and that the preset duration tfc is fixed at 50

  msec. (jerks remain in the acceleration of the vehicle

  cule) and Figure 18 shows the result when the preset value Th of the half-clutch torque is fixed at 58% of To and the preset duration tfc is fixed at 150 msec. (of

  jerks remain in acceleration of the vehicle).

  The first embodiment allows the duration of the clutch release operation and the duration of the clutch release operation when changing

  of the speed of the transmission 20 are both connected

  shortened and the total time required to change the gear ratios of the transmission 20 is shortened by performing steps 301 to 307 in Figure 6 described

26 2772095

  above associated with steps 201 to 216 in FIG. 5.

  Thus, this allows the feeling of free running of the vehicle.

  cule to be lessened, to the feeling of direct driving

  to be improved and the driving feel and the stability

  lity of the command to be improved.

  It should be noted that although the speed of the mo-

  Has not been fixedly controlled regardless of the load during and after the clutch by providing for step 301 in the clutch control program when the gear change is complete,

  as it is represented on figure 6 in the mode of re-

  alization described above, it is possible to carry out the first embodiment while eliminating this step 301.

  Figures 19 to 23 show a second embodiment

  sation (in which the present invention is applied to

  a vehicle fitted with a gearbox change system

  manual clutch and automatic clutch) of this in-

  vention. As shown in simplified form in FIGS. 19 and 20, the gear shift lever 23

  is coupled to the selection and change lever shaft-

  gear 24 by a link lever 25 so that the gear selection and shift lever shaft

  24 is changed in conjunction with the lever control

  size 23 via the connection lever 25 in the second mode

  of achievement. A change of stroke speed sensor

  speed S7 detects a command speed Sh of the

  gear lever 23 and between it in the control unit

  electronic ECU control. Gear shift load switches FSW and RSW mounted between the gear lever 23 and a gear shift button 26 detects a driver's gear shift request

  (the FSW speed change load switch de-

  tect the start of the shift lever 23 command at gear ratio 1, 3 or 5 when it is closed and

27 2772095

  the gear ratio load switch RSW detects the start of the gear lever control 23 at gear ratio 2.4 or R when closed) and closed / open signals from the gear shift load switches FSW and RSW entered the control unit

  ECU electronics. The structure of the second embodiment other than that described above is substantially the same as

  that of the first embodiment shown in FIGS. 1 to 3, so that the same components are represented by the same reference numbers and their explanation will be omitted here. It should be noted that the gear shift lever sensor S4 detects the

SP gear position.

  The UCE electronic control unit controls the operations

  rations of the throttle control member Ai, the clutch control member A3 and the like, respectively. It is composed of a microcomputer or the like containing a timer and executes a control program according to the flowcharts represented in FIGS. 21 and 23 on the

  basis of the respective signals (vehicle speed SPD, vi-

  engine size Ne, throttle opening angle 0, posi-

  gear ratio SP, clutch stroke CRCST and gear change speed Sh) detected by the respective sensors, on the activation / deactivation or the activation signal of the ignition switch IG starter and the activation / deactivation signal of the FSW and RSW speed change load switches. We will now explain the operation of the second

  embodiment by referring to the flowchart represented

  shown in Figures 21 to 23. The electro-

  nique begins to run the program in step 401 when

  IG ignition switch is CLOSED (handled from OPEN to CLOSED). It then initializes the program in step 402, performs the input processing of the signals

28 2772095

  detected (vehicle speed SPD, engine speed Ne, throttle opening angle 0, gear ratio position SP, clutch stroke CRCST and speed

  speed change Sh) from the respective sensors

  tifs, the activation / deactivation or activation signal of the ignition switch IG starter and the activation / deactivation signal of the speed change load switches FSW and RSW in step 403, selects

  a clutch control mode Cmode in step 404 and exe

  cute the respective steps 405 to 413 corresponding to the mo-

  of the respective clutch control units Cmode = 0 to Cmode = 8. It should be noted that the electronic control unit UCE performs various failure treatments in step 414 and

  returns to step 403 after performing each of the steps

  pes 405 to 412. The electronic control unit UCE repeats the processing to execute steps 403 to 414 for a predetermined period of 4 msec. The UCE electronic control unit ends the program excitation at

  step 415 after performing step 413.

  Step 405 is a clutch disengagement control program when the engine is started which is executed

  when the clutch control mode Cmode = 0 is se-

  selected in step 404. The clutch control mode Cmode = 0 is selected under the condition where the vehicle speed SPD and the engine speed Ne are equal to 0, that the clutch stroke CRCST is equal or less than a predetermined value (clutch clutch condition), that the gear position SP is neutral or reverse and that the ignition switch IG is CLOSED. The contents of the command executed at this time consist in causing the clutch control member A3 to quickly perform a

  declutching operation to disengage quickly and completely-

  the clutch 30 (by supplying pressurized oil to the clutch release cylinder 51 from

29 2772095

  accumulator 53 via control valve 52) after checking that the oil pressure inside

  accumulator 53 is equal to or greater than the pre-

  established by a detection signal from an interrup-

  pressure tor 54 and activate the starter motor, not shown, to activate the motor 10 when the clutch is fully disengaged. It should be noted that when the hydraulic pressure inside the accumulator 53 is lower than the preset value, the control valve 52 does not operate until the hydraulic pressure inside the accumulator 53 is increased to be equal to or greater than the preset value by causing the

motor pump 57.

  Step 406 is a program for controlling clutch disengage during idling (the vehicle is stationary) which is executed when the clutch control mode Cmode = 1 is selected in step 404 The clutch control mode Cmode = 1 is selected in

  the condition where the speed of the spd vehicle is equal or equal

  lower than the predetermined value including the value zero, that the engine speed Ne is equal to or less than the predetermined value which is not equal to zero, the stroke of the CRCST clutch is equal to or greater than a value

  predetermined (the clutch is fully disengaged), the po-

  SP gear ratio and the neutral gear and the throttle opening angle 0 is equal to or less than

  a predetermined value. The contents of the command exe-

  cut at this time consist in maintaining the organ of com-

  clutch clutch A3 in operating state de-

  clutch to maintain the clutch 30 in the fully disengaged state. Step 407 is a hold control program

  clutch disengagement when starting which is exe

  cut when the clutch control mode Cmode = 2 is selected in step 404. The clutch control mode

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  Cmode = 2 is selected under the condition where the speed

  SPD vehicle is equal to or less than the preset value

  complete including the value zero, the engine speed Ne is equal to or less than the predetermined value which is not equal to zero, the stroke of the CRCST clutch is equal to or greater than the predetermined value (the clutch is fully disengaged ), the gearshift load switch FSW and RSW is CLOSED because the gearshift lever 23 was just controlled by the driver after starting the engine 10. The contents of the command executed at this time consist of maintain the clutch control member A3 in a functional state

  clutch to keep clutch 30 in full condition

disengaged.

  Step 408 is a clutch control program for the clutch upon start-up which is executed when the clutch control mode Cmode = 3 is selected in step 404. The clutch control mode Cmode = 3 is selected under the condition where the speed of the vehicle SPD is equal to or less than the predetermined value including zero, the speed of the engine Ne is equal to or less than the predetermined value which is not equal to zero, the stroke of the CRCST clutch is equal to or greater than the value

  predetermined (the clutch is fully disengaged), the po-

  SP gear ratio is any of the first to fifth gear or reverse gear and the throttle opening angle 0 is equal to or greater

  at the predetermined value. The contents of the command exe-

  cut at this time consist in causing the clutch control member A3 to progressively carry out the operation

  clutch to engage clutch 30 at pre-speed

  determined. Step 409 is a clutch declutching control control program during normal driving mode which is executed when the control mode

31 2772095

  clutch mode Cmode = 4 is selected in step 404. The clutch control mode Cmode = 4 is selected under the condition o the vehicle speed SPD and the speed of the

  motor Ne are equal to or greater than the predeter-

  mined, the CRCST clutch stroke is equal to or less than the predetermined value (clutch clutch state) and the gear ratio position SP is

  any of the second speed ratios,

  third or reverse and the load switch

  gear change FSW is OPEN or the gear position

  SP speed port and first speed reports,

  third or fifth and the charge charge switch

  RSW speed port is OPEN (load switch

  gear ratio in the direction of traction is. OR-

  GREEN). The contents of the command executed at this time consist in maintaining the clutch 30 in the fully engaged state without implementing the control member of

clutch A3.

  Step 410 is a clutch control program

  of the clutch when a gear change (a change-

  gear ratio) is required, which is executed

  when the clutch control mode Cmode = 5 is se-

  selected in step 404. The clutch control mode Cmode = 5 is selected under the condition where the vehicle speed SPD and the engine speed Ne are equal to or greater than the predetermined values, the travel of

  the CRCST clutch is equal to or less than the pre-

  determined (clutch clutch condition) and position

  SP gear ratio is the gear ratio of se-

  shift, fourth, reverse or neutral and the gear shift load switch FSW is CLOSED or the gear position SP and the gear ratio first, third, fifth or neutral and the gear ratio load switch

  RSW is CLOSED (the speed ratio charge switch

32 2772095

  size in the direction of traction is CLOSED). The

  contained in the command executed at this time will be de-

  subsequently written with reference to the organization chart

felt in figure 22.

  Step 411 is a clutch control program for the clutch when the gear change is complete which is executed when the clutch control mode

  Cmode = 6 is selected in step 404. The mode of com-

  clutch command Cmode = 6 is selected under the condi-

  o the vehicle speed SPD and the engine speed Ne are equal to or greater than the predetermined values, the stroke of the CRCST clutch is equal to or greater than the predetermined value (the clutch is fully disengaged) and the position of the gear ratio SP speed and the second, fourth or reverse gear ratio and

  the FSW gear ratio load switch is open or

  green or the position of the SP gear ratio and the first, third or fifth gear ratio and

  the gear shift load switch RSW is OU-

  GREEN (the speed load switch in the pulling direction is OPEN). Contents in the order

  executed at this time will be described later in ref-

  referring to the flowchart shown in Figure 23.

  Step 412 is a clutch disengagement control program when the vehicle is stopped which is executed

  when the clutch control mode Cmode = 7 is se-

  selected in step 404. The clutch control mode Cmode = 7 is selected under the condition where the vehicle speed SPD and the engine speed Ne are equal or

  lower than the predetermined values which are not equal

  at zero, the stroke of the CRCST clutch is equal or equal

  lower than the predetermined value (the clutch is

  crossed out) and the butterfly opening angle O is equal or equal

  lower than the predetermined value. The contents of the command executed at this time consist in bringing the organ

33 2772095

  clutch control A3 to gradually perform the clutch release operation at the predetermined speed for

  fully disengage clutch 30 at the predetermined speed

  born. Step 413 is a program for controlling the clutch of the clutch when the engine is stopped, which is executed

  when the clutch control mode Cmode = 8 is se-

  selected in step 404. The clutch control mode Cmode = 8 is selected under the condition where the vehicle speed SPD and the engine speed Ne are equal to

  zero and that the stroke of the CRCST clutch is equal or greater

  less than the predetermined value (the clutch is total-

  disengaged) and when a predetermined period has elapsed

  after the IG ignition switch has been opened.

  The contents of the order executed at that time consist

  attempt to bring the clutch control member A3 to ef-

  perform the clutch operation to engage the clutch 30. Next, the clutch disengage control program when a gear change is required will be explained with reference to the flow chart shown in Figure 22. L the electronic control unit UCE judges whether or not the speed of change of speed Sh entered in step 403 is equal to or greater than a preset value SO in step 501 in FIG. 22 and advances to step 502 when 'it is judged to be "no" or jumps to step 516 when it is judged to be "yes". It then calculates the engine torque T on the basis of the engine speed Ne and the opening angle of the throttle valve 0 entered in step 403

  in FIG. 21 and with reference to a table of corres-

  motor torque weight (memorized in advance of the electronic control unit UCE), calculates a first order delay motor torque Te from this via a filter

  and stores it as a fixed torque in step 502.

34 2772095

  Then, a branch corresponding to a value of one

  engine torque conservation indicator Tf is selected

  tiated in step 503. The electronic control unit UCE executes steps 504, 505, 506, 507 and 508 when the branch "0" (mode for calculating a preset value and a preset duration of the motor torque) is selected, execute steps 509, 510, 511 and 508 when branch "1" (mode for transferring the preset value of the motor torque) is selected, execute steps 512, 513, 514, 515 and 508 when branch "2" (mode to maintain the

  motor torque at the preset value during the pre-

  established) is selected and performs steps 516, 517 and 508 when branch "3" (declutching operation mode

clutch) is selected.

  In step 504, the electronic control unit UCE calculates and stores a duration for fixing and maintaining

  TFE motor torque based on the gear position

  tesse SP entered in step 403 in FIG. 21 and the engine torque (fixed torque) Te calculated is memorized in step 502, and by reference to a correspondence table for the duration of engine engine fixation and maintenance (which was obtained

  based on various experiences and analyzes and memorization

  placed in advance in the UCE electronic control unit).

  In step 505, the electronic control unit UCE calculates

  and stores the target motor torque Ti on the basis of the vi-

  tesse of the engine Ne and of the speed ratio position SP entered in step 403 in FIG. 21 and of the engine torque Te calculated and stored in step 502 and with reference to a target engine torque correspondence table (which was obtained on the basis of various experiments and analyzes and stored in advance in the electronic control unit UCE). In step 506, the electronic control unit UCE calculates and stores a target throttle opening angle Oi to establish the output torque of the engine 10 to the target engine torque Ti calculated and stored in step 505 on the

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  base of the engine speed Ne and by reference to a ta-

  ble of engine torque correspondence (which is stored in advance in the electronic control unit UCE). In step 507, the electronic control unit UCE passes the value "0" of the indicator Tf which was initialized in step 402 in FIG. 21 to "1". Then, the electronic control unit UCE controls the drive of the throttle control member Ai so as to adjust the opening angle of the throttle 0 to the opening angle of the

target butterfly Oi in step 508.

  In step 509, the electronic control unit UCE calculates and stores an opening difference 0e between the opening angle of the target throttle Oi and the opening angle of the current throttle 0. It then determines whether

  yes or no the absolute value of the opening difference Ge is less than a preset value Gel in step 510.

  It passes the value "1" of the indicator Tf which was modified in step 507 to "2" in step 511. It should be noted that the execution of steps 509, 510 and 508 means that the butterfly control member Ai controls the angle

  butterfly opening 0 against feedback.

  The UCE electronic control unit processes

  subtraction tement during the fixation fixation period of the calculated target torque tfe memorized in step 504

  and stores the result in step 512. It also determines

  continued whether or not the duration for fixing and maintaining the target torque memorized in step 512 is equal to or greater than 0 in step 513. The electronic control unit UCE passes the value "2" of the indicator Tf changed in step 511 to "3" in step 514. The electronic control unit UCE also calculates an opening angle of the engine speed throttle valve by which the engine speed will not increase even when the clutch is disengaged on the basis of the engine speeds Ne, passes the angle of the opening of the target throttle Oi to it and

36 2772095

  stores this value. It should be noted that

  the execution of steps 512, 513 and 508 means that the du-

  pre-established target motor torque Ti is maintained.

  The electronic control unit UCE controls the drive of the clutch control member A3 in order to completely disengage the clutch 30 in step 516. It then passes the value "3" of the indicator Tf which has summer

  changed in step 514 to "0" in step 517.

  In this regard, the execution of steps 501 to 517 represents

  felt in Figure 22 described above allows the engine torque T to be reduced to the preset value (calculated and stored in step 505, for example 45% of the engine torque

  T at time a) Ti by changing the opening angle of the pa-

  pin 0 at the angle of the opening of the target throttle valve Oi which fixes the engine torque output 10 to the target engine torque Ti at

  time a) (when the gear change has been re-

  quis) before the clutch 30 is fully disengaged and thus allows a first inflection point Pi in a curve characteristic of the fluctuations in acceleration

  of the vehicle to occur when the acceleration of the vehicle

  cule is almost equal to 0 and the fluctuation of the acceleration of the vehicle which subsequently occurs from being brought to converge in the vicinity of a value almost equal to 0 by completely disengaging the clutch 30 by the control member d clutch A3 after maintaining the

  motor output control for the pre-

  established (the calculated duration stored in step 505, by

  example 95 msec) Tfe as shown in Figure 7 when

  the speed change Sh is below the preset value So in the same way as in the first mode

of achievement.

  Consequently, since the inventive method allows the acceleration of the vehicle to be brought to converge in the vicinity of an almost zero value after having changed the acceleration of the vehicle from the value o the

37 2772095

  gear change was required (at time a) to almost

  that a value equal to 0 during the preset time Tf by disengaging the clutch 30 when the gear change of the transmission is required, allows the change in vehicle acceleration which occurs during the clutch disengaging operation to be minimized and shortened temporarily and to shock or impact occurring

  during the clutch disengagement operation to be re-

  duit. Thus, the inventive process can provide a sense of

  comfortable driving with less shock or impact while shortening the clutch release time

of the clutch.

  Now the clutch control program of

  the clutch when the gear change is complete

  ra explained with reference to the flowchart shown in Figure 23. The electronic control unit UCE executes a motor speed control program (a control program for driving the throttle control member A1 so as to maintain the engine at Ne engine speed just before the gear change) to set the Ne engine speed without taking the load into account

  the clutch 30 and after in step 601 in FIG. 23.

* Then, a branch corresponding to a value of

  the clutch torque control indicator Cf is

  selected in step 602. The electronic control unit UCE executes steps 603, 604, 605, 606 and 607 when the branch "0" (mode for calculating a value of half-engaged torque targets a holding fixation time of half-engaged torque) is selected, performs steps 608, 609, 610, 611 and 607 when branch "1" (mode for transfer to half-engaged state) is selected, performs steps 612, 613, 614 and 607 when the branch

  "2" (mode to maintain half-engaged state) is selected

  tiated performs steps 615, 616 and 607 when the branch

38 2772095

  che "3" (mode to fully engage the clutch) is selected. In step 603, the electronic control unit UCE calculates and stores the input torque To necessary to obtain the engine speed Ne and the vehicle speed SPD when the clutch 30 is fully engaged on the basis of the speed of the motor Ne, of the position of the speed ratio SP, of the speed of the vehicle SPD entered in step 403 in FIG. 21 and with reference to an input torque correspondence table (which is stored in advance in the UCE electronic control unit). In step 604, the electronic control unit UCE calculates and stores a target half-clutch torque Th on the basis of the input torque To calculated and stored in step 603 and by

  reference to a half torque correspondence table

  target clutch (which was obtained on the basis of various experiments and analyzes and stored in advance in the electronic control unit UCE). In step 605, the electronic control unit UCE calculates and stores a target clutch stroke CRCSTi on the basis of the target half-clutch torque Th calculated and stored in step 604 and by reference to a stroke correspondence table

  target clutch (which was obtained on the basis of various

  his experiences and analyzes and memorized in advance in the electronic control unit UCE). In step 606, the electronic control unit UCE passes the value "O" of an indicator CF which was initialized in step 402 on

  Figure 21 to "1". Then the electro-

  nique UCE controls the drive of the clutch control member A3 so as to fix the clutch stroke CRCST

  at the target clutch stroke CRCSTi in step 607.

  In step 608, the electronic control unit UCE calculates and stores a difference in stroke STe between the target clutch stroke CRCSTi and the clutch stroke

  current CRCST. It then determines whether or not the

39 2772095

  their absolute of the stroke difference STe is less than a preset value STel in step 609. In step 610, the electronic control unit UCE calculates and stores a duration of fixing and holding the half-engaged torque TFC on the basis of the speed ratio position SP entered in step 403 in FIG. 21 and of the input torque To memorized in step 603 and with reference to a table of

  duration of fixation and maintenance duration

  half-clutched ple (which was obtained on the basis of various experiments and analyzes and stored in advance in the electronic control unit UCE). It passes the value "1" of the indicator CF which was modified in step 606 to "2" in step 611. It should be noted that the execution

  steps 608, 609 and 607 means that the control unit

  clutch clutch A3 controls clutch travel

CRCST on the other hand.

  The UCE electronic control unit processes

  subtraction during the half-clutch torque holding fixation time tfc calculated and stored at

  step 610 and stores the result in step 612. It de-

  then ends whether or not the duration of fixing and maintaining the half-clutch torque tfc memorized in step 612 is equal to or less than zero in step 613. The electronic control unit UCE passes the value "2" from the CF flag which was changed in step 611 to "3" in step 614. It should be noted that the execution of steps 612, 613 and 607 means that the preset duration of

  the target clutch stroke CRCSTi is maintained.

  The electronic control unit UCE controls the drive of the clutch control member A3 in order to fully engage the clutch 30 in step 615. It then passes the value "3" of the indicator CF which has been

  modified in step 614 to "0" in step 616.

  In this regard, the execution of steps 601 to 616 represents

  shown in Figure 3 described above allows a pre-

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  1st inflection point P2 to occur at the pre-

  established in the curve of the characteristics of fluctuations in the acceleration of the vehicle obtained by the state of half-engaged torque by placing the clutch 30 from the fully disengaged state in the half-engaged state by the clutch control A3 in order to increase the input torque which is transmitted from the output shaft 11 of the engine to the input shaft 21 of the transmission 20 to the predetermined value (the value calculated and stored at the stage

  604, for example, 58% of the calculated input torque To and

  moralized in step 603) Th decided by the speed of the vehicle and the speed ratio when the gear change is completed when the completion of the gear change of the transmission 20 is detected (at time b) and allows

  that the subsequent fluctuation in vehicle acceleration be brought to converge in the vicinity of the value

  preset by fully engaging the clutch 30

  by the clutch control member A3 after having

  naked the state of half-engaged torque during the pre-

  blie (the duration calculated and stored in step 610, by

  example, 95 msec.) tfc as shown in the fi

  gure 13 in the same way as in the first mode of re-

  alization. Consequently, since the inventive method allows the acceleration of the vehicle to be brought to converge in the vicinity of the preset value after having changed the acceleration of the vehicle from a value almost

  zero when the gear change is completed at the

  their preset during the preset time tfc in em-

  braking the clutch 30 when the gear change of the transmission 20 is completed, it allows the change in the acceleration of the vehicle which occurs during the clutch engagement operation to be minimized and

  temporarily shortened and the shock or impact occurs

  duisant during the clutch operation of the clutch either

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  reduced. Thus, the inventive process can provide a sense of

  tion of comfortable driving less sensitive to shocks or impacts while shortening the duration of the clutch engagement operation. The shortening of the duration of the clutch engagement operation in turn allows the duration of the half-engaged state to be shortened and that

  the life of the clutch 30 is extended.

  The second embodiment also allows the duration of the clutch disengaging operation and the duration of the clutch clutch operation when changing the speed of the transmission 20 to be both shortened and that the total time required to change the speed ratio of the transmission 20 be shortened by performing steps 601 to 607 in the figure

  23 described above associated with steps 501 to 517 represented

  felt in FIG. 22. Thus, it allows the feeling of free travel of the vehicle to be reduced, that the feeling of direct driving is improved and that the feeling of

  control and stability of the control are improved.

  In addition, the second embodiment allows the clutch 30 to be precisely and completely disengaged without

  cause delay in the change command speed

  speed by jumping to step 516 by determining that it is "yes" when the speed of change of speed Sh is equal to or greater than the preset value

  So by performing step 501 in Figure 22 and ordering

  during the drive of the clutch control member A3 so as to completely disengage the clutch 30 by executing

step 516.

  Although the preferred embodiments have been de-

  crits, variations of these will be obvious to humans

  of art within the scope of the concepts of pre-

  invention which are delimited by the claims

following.

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Claims (2)

  1. A clutch control method for controlling clutch release and clutch operations of a clutch (30) which is interposed between an output shaft (11) of an engine   (10) and a transmission input shaft (21) of a vehicle   cule and which couples / uncouples the transmission (20) of a torque corresponding to a driving state using a clutch control member (A3), characterized in that the improvement comprises the steps consisting in: controlling an output from said motor (10) in order to reduce the engine torque transmitted from the output shaft (11) from said motor (10) to the input shaft (21) from said transmission   (20) via said clutch (30) to a preset preset value   given by the engine torque and a gear ratio at the time when the gear change was required when the demand for the gear change of said transmission (20) is detected so that a first inflection point occurs when the vehicle acceleration is almost   equal to zero in a characteristic curve of fluctua-   acceleration of the vehicle obtained by controlling the output of the engine; and   fully disengage said clutch (30) through said or-   clutch control valve (A3) after having maintained control of said engine output for a preset time so that the fluctuation in vehicle acceleration occurring thereafter converges in the vicinity of almost zero value.   2. Clutch control method for controlling the disengagement and clutch operations of a clutch (30) which is interposed between an output shaft (11) of an engine   (10) and an input shaft of a transmission (21) of a   vehicle and which couples / uncouples the transmission (20)   of a torque corresponding to a driving state in use 43 2772095   sant a clutch control member (A3), characterized in that the improvement comprises the stages consisting:   place said clutch (30) from a total state   disengaged in a semi-engaged state by said clutch control member (A3) in order to increase the input torque transmitted from the output shaft (11) of said motor (10) to the drive shaft input (21) of the transmission (20) via said clutch (30) to a preset preset value   by the vehicle speed and the minimum speed ratio   where the gear change is complete when   completion of the gear change of said transmission-   sion (20) is detected so that a first point of inflection occurs at the preset value in the characteristic curve of the fluctuations of the acceleration of the vehicle obtained by the half-engaged state; and fully engage said clutch (30) after   maintained said half-engaged state for a pre-set period   blie so that the fluctuation in vehicle acceleration   cule occurring thereafter converges in the vicinity of the preset value.