JP4930248B2 - Vehicle clutch state detection device - Google Patents

Description

  The present invention relates to a vehicle clutch state detection device for detecting engagement / release of a clutch in a vehicle in which rotational power of an engine is transmitted to wheels via a clutch and a transmission.

Patent Document 1 discloses a clutch state detection device that detects engagement / disengagement of a clutch that intermittently transmits and receives rotational power from an engine to a power transmission device that transmits rotational power of the engine to wheels. An apparatus is disclosed that detects an instantaneous rotation speed and determines an open state of the clutch based on fluctuations in the instantaneous rotation speed.
JP-A-2005-195170

  By the way, if the accelerator is suddenly closed while the clutch is engaged, the engine speed fluctuates due to the shock of the accelerator operation. Therefore, when the clutch disengaged state is determined based on the increase change of the engine speed, the accelerator close There was a possibility that the increase in rotation due to the shock would be erroneously determined to be due to the release of the clutch.

  The present invention has been made in view of the above problems, and distinguishes between the increase in rotation caused by the shock of closing the accelerator while the clutch is engaged and the increase in rotation caused by the release of the clutch, thereby accurately detecting the release of the clutch from fluctuations in the engine speed. The purpose is to be able to judge well.

For this reason, in the present invention, a threshold value that is smaller as the vehicle speed is higher is set, and the release of the clutch is determined when the engine rotational speed increases more than the threshold value after the accelerator is closed. did.

  According to the above invention, when the increase in engine rotation speed after the accelerator is closed exceeds the threshold, it is determined whether the clutch is released. The threshold is set according to the vehicle speed at that time.

  To perform manual shifting operation, release the accelerator pedal that was previously depressed, and then depress the clutch pedal, the torque transmission between the engine and the transmission is cut off, and the engine speed increases. Therefore, the release of the clutch is determined based on the rotation increase.

  However, if the accelerator is closed while the clutch is engaged, the engine speed may fluctuate due to a shock accompanying the closing of the accelerator, and the increase in rotation accompanying the change and the increase in rotation due to the release of the clutch are based on a certain threshold. Are difficult to distinguish.

  Therefore, in the present invention, the threshold value is variably set based on the vehicle speed to distinguish between the increase in rotation due to the closing shock of the accelerator while the clutch is engaged and the increase in rotation due to the release of the clutch.

  In other words, the rotational fluctuation due to shock when the accelerator is suddenly closed varies greatly depending on the vehicle speed, so by setting the threshold according to the vehicle speed, it is possible to set a threshold that does not exceed the rotational fluctuation due to the accelerator closing shock. Therefore, it is possible to prevent erroneous determination that the increase in rotation accompanying the closing of the accelerator is due to the release of the clutch.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a system diagram of a vehicle in which an engine with a manual transmission is mounted in the embodiment.

  Rotational power of an engine (internal combustion engine) 1 mounted on the vehicle is transmitted to driving wheels (not shown) via a clutch 2 and a manual transmission 3.

  The clutch 2 is released / engaged by the operation of the clutch pedal 9 by the driver, and the gear position (for example, 1st to 6th speed, reverse) of the manual transmission 3 is selected by the operation of the shift lever 4 by the driver. .

  An electronic control throttle device 6 is provided in the intake passage 5 of the engine 1.

  An engine control unit (ECU) 7 incorporating a microcomputer controls the electronically controlled throttle device 6 in accordance with the accelerator operation by the driver, so that the intake air amount of the engine 1 and, in turn, the output of the engine 1 can be reduced. In addition to controlling, the fuel supply device 21 is controlled to control the fuel supply amount so that the desired air-fuel ratio is obtained with respect to the intake air amount, and further the ignition timing by the ignition device 22 and the like are controlled.

  Signals from various sensors are input to the engine control unit 7.

  The accelerator pedal sensor 11 (accelerator detection means) outputs a signal corresponding to the accelerator pedal depression amount (accelerator opening) APO.

  The crank angle sensor 12 (engine rotation detection means) outputs a signal synchronized with the rotation of the crankshaft 8 of the engine 1, and can detect the engine rotation speed NE from this signal.

  The vehicle speed sensor 13 (vehicle speed detection means) outputs a signal synchronized with the rotation of the output shaft of the manual transmission 3, and can detect the vehicle speed VSP from this signal.

  The shift position sensor 14 outputs a signal corresponding to the position of the shift lever 4 and can detect the actual gear position (gear ratio). Therefore, the shift position sensor 14 corresponds to a gear ratio detecting means for detecting the gear ratio of the manual transmission 3.

  Further, the clutch pedal 9 includes a first clutch switch 16 (release start detecting means) that is turned on and off at a clutch release operation start position (clutch pedal start position) set in advance within the stroke range. In addition, a second clutch switch 17 (disengagement end detection means) that switches on and off at a clutch disengagement operation end position (stepping end position) set in advance within the stroke range is provided.

  Therefore, when the driver depresses the clutch pedal 9 more than the play of the pedal, first, the first clutch switch 16 is switched on and off, and then the maximum stroke that is predicted to be fully released. When the clutch pedal 9 is depressed to the vicinity, the second clutch switch 17 is switched on / off.

  The first clutch switch 16 maintains an on (or off) state until the clutch pedal 9 is depressed at the clutch release operation start position (clutch pedal start position), and the clutch release operation start position (clutch). It is assumed that the position is switched off (or on) when reaching the pedal depression position, and then the off (or on) state is maintained until the maximum stroke.

  Similarly, the second clutch switch 17 maintains an on (or off) state until the clutch pedal 9 is depressed to the clutch disengagement operation end position (stepping end position), and the clutch disengagement operation end position (stepping on). When the end position is reached, the switch is turned off (or on), and then the off (or on) state is maintained until the maximum stroke.

  In place of the first clutch switch 16 and the second clutch switch 17, a stroke sensor for detecting the stroke amount of the clutch pedal 9 is provided, and the stroke detection value by the stroke sensor and the start / end positions of the clutch operation are provided. By comparing the respective thresholds corresponding to the above, it is possible to detect the start position of the clutch release operation and the end position of the clutch release operation.

  As described above, the engine control unit 7 controls the intake air amount and the fuel supply amount of the engine 1 and has a function of detecting opening / closing of the clutch 9, for example, when the clutch 9 is opened. Control is performed to suppress the engine speed increase by correcting the ignition timing.

  The correction of the ignition timing retards the increase in rotation by retarding the ignition timing when the engine rotation increases with the release of the clutch, thereby suppressing the increase in rotation at the time of shifting.

  The flowchart of FIG. 2 shows a first embodiment of a calculation process (release determination means) for detecting the release / engagement of the clutch 9 in the engine control unit 7.

  First, in step S101, detection values such as the vehicle speed VSP, the accelerator opening APO, the gear position, and the engine speed NE are read.

  In step S102, based on the accelerator opening degree read in step S101, it is determined whether or not the accelerator is in a closed state (a fully closed state in which the accelerator pedal is released).

  When the accelerator is in the open state (depressed state of the accelerator pedal), the routine proceeds to step S103, where the flag F is set to 0, and then this routine is terminated.

  On the other hand, when the accelerator is closed, the process proceeds from step S102 to step S104.

  In step S104, it is determined whether or not the flag F is 1 to determine whether or not it is the timing when the accelerator is switched from the open state to the closed state.

  As will be described later, when it is determined that the accelerator is in the closed state, 1 is set in the flag F, so that the accelerator was in the open state until the previous time, but this time in the closed state. If the process proceeds to step S104, the flag F is 0, and the process proceeds from step S104 to step S105.

  In step S105, the engine speed NE at the timing when the accelerator is switched from the open state to the closed state is stored.

  In the next step S106, 1 is set in the flag F. Therefore, if the accelerator is continuously closed after the next time, it is determined that the flag F is 1 in step S104, and the process bypasses steps S105 and S106 and proceeds to step S107.

  In step S107, the basic value SLb of the threshold SL used for determining whether the clutch 2 is released is calculated based on the vehicle speed VSP at that time.

  As shown in the figure, the basic value SLb is set to a smaller value as the vehicle speed VSP is higher.

  In the next step S108, a correction coefficient K for the basic value SLb is calculated based on the gear position (gear ratio) at that time.

  As shown in the figure, the correction coefficient K is set to a smaller value as the gear position is on the high gear side (high speed side).

  The gear position (gear ratio) can be determined from the detection result of the shift position sensor 14 and can be calculated from the vehicle speed VSP and the engine speed NE.

  In step S109, the basic value SLb calculated in step S107 is multiplied by the correction coefficient K calculated in step S108, and the result is set to a threshold SL (SL = SLb · K) (threshold setting means).

  Accordingly, the threshold value SL is set to a smaller value as the vehicle speed VSP is higher and as the gear position (gear ratio) is on the high gear side (high speed side).

  The correction by the correction coefficient K can be omitted, and the threshold value SL can be set only from the vehicle speed VSP, and the correction value set according to the gear position (gear ratio) and the basic value SLb can be added or subtracted. The threshold value SL can be calculated.

  Furthermore, the threshold value SL can be set with reference to a map that stores the threshold value SL corresponding to the vehicle speed VSP and the gear position (gear ratio), and the threshold value SL and the gear position (based on the vehicle speed VSP) can be set. The larger one of the threshold values SL set based on the gear ratio) can be selected as the final threshold value SL.

  In step S110, the deviation ΔNE (ΔNE = latest engine rotation) between the engine rotation speed NE at that time and the engine rotation speed NE (the stored value in step S105) at the timing when the accelerator is switched from the open state to the closed state. The speed NE-the engine speed NE when the accelerator is closed is calculated.

  In the next step S111, it is determined whether or not the deviation ΔNE exceeds the threshold value SL.

  When the deviation ΔNE exceeds the threshold value SL, it is determined that the engine speed NE has increased due to the release of the clutch 2 (release determination means), and the process proceeds to step S112, where the clutch 2 Open determination is performed (see FIG. 3).

  On the other hand, if the deviation ΔNE is less than the threshold value SL, it is determined that the clutch 2 is still in the engaged state, and step S112 is bypassed and this routine is terminated.

  Note that, based on the release determination of the clutch 2 in the step S112, the engine control unit 7 starts engine rotation control such as ignition timing delay angle correction for suppressing the increase in rotation accompanying the release of the clutch. Or switching the gain in air-fuel ratio feedback control.

  According to the above-described embodiment, when the release of the clutch 2 is determined from the increase in rotation after the accelerator is closed, the threshold value SL used for determining the increase in rotation is set based on the vehicle speed VSP, so It is possible to prevent erroneous determination that the clutch 2 is released.

  If the accelerator is closed while the clutch 2 is engaged, the engine rotation speed fluctuates due to the shock of the accelerator operation, but the rotation fluctuation at this time increases as the vehicle speed decreases, so by increasing the threshold value SL at a low vehicle speed, The increase in rotation due to the accelerator closing shock can be made to be less than the threshold value SL, thereby avoiding erroneous determination of the increase in rotation due to the accelerator closing shock as the clutch being released.

  On the other hand, when the vehicle speed increases, the accelerator closing shock decreases and the rotational fluctuation also decreases. Therefore, even if the threshold value SL is decreased, it is possible to prevent erroneous determination of the increase in rotation due to the accelerator closing shock as the clutch being released, and By decreasing the threshold value SL, it is possible to quickly detect an increase in rotation due to clutch release.

  If the release of the clutch can be detected promptly, for example, the start of ignition timing control that suppresses the increase in rotation accompanying the release of the clutch becomes earlier, and the increase in rotation can be further reduced.

  By the way, in the case of the above embodiment, the threshold value SL is increased in the low vehicle speed range so that the clutch release is not erroneously determined based on the rotation increase due to the accelerator closing shock, so the clutch is actually released. It can be avoided that the release determination is made in a state where it is not.

  However, particularly in an engine having a large rotational increase due to the accelerator closing shock, it is necessary to increase the threshold value SL in the low vehicle speed range. As a result, it may not be possible to quickly determine the clutch release in the low vehicle speed range. .

  Therefore, in the second embodiment shown in the flowchart of FIG. 4, the threshold value SL is switched based on the signals of the first clutch switch 16 and the second clutch switch 16, and the release determination of the clutch 2 is forcibly performed. It is like that.

  In the flowchart of FIG. 4, each step from step S201 to step S209 performs the same processing as step S101 to step S109, and thus the description thereof will be omitted and will be described in detail from step S210 onward.

  In step S210, it is determined whether the on / off state of the first clutch switch 16 corresponds to a state where the clutch pedal 9 is depressed more than the start position (depressing start position) of the clutch release operation.

  For example, when the first clutch switch 16 is turned on when the clutch pedal 9 is not depressed, and is depressed to the start position (depressing start position) of the clutch release operation, the first clutch switch 16 is turned off. Thus, it is determined whether or not the first clutch switch 16 is in an OFF state.

  If the clutch pedal 9 is not depressed to the start position of the clutch release operation, the process proceeds to step S213, and the engine speed NE at that time and the engine at the timing when the accelerator is switched from the open state to the closed state. A deviation ΔNE (ΔNE = the latest engine speed NE−the engine speed NE when the accelerator is closed) from the rotational speed NE (the stored value in step S205) is calculated.

  In step S214, it is determined whether or not the deviation ΔNE exceeds the threshold value SL calculated in step S209.

  If the deviation ΔNE exceeds the threshold value SL, it is determined that the engine speed NE has increased due to the clutch 2 being released, and the routine proceeds to step S215 to determine whether the clutch 2 is released.

  On the other hand, when the deviation ΔNE does not exceed the threshold value SL, the clutch 2 has not yet been released (engaged state), so it is determined that no rotation increase exceeding the threshold value SL has occurred, This routine is ended without proceeding to the release determination in step S215.

  On the other hand, if it is determined in step S210 that the first clutch switch 16 is switched on and off and the start position (stepping start position) of the clutch release operation is detected, the process proceeds to step S211.

  In step S211 (threshold lowering means), a process of switching the threshold SL to be compared with the deviation ΔNE in step S214 to a post-depression threshold SLa smaller than the threshold SL calculated in step S209 (see FIG. 5).

  The post-depression threshold value SLa may be a fixed value (single point constant), a value obtained by subtracting a constant value from the threshold value SL calculated in step S209, or a predetermined ratio of the threshold value SL calculated in step S209 ( <100%).

  Further, the minimum value of the basic threshold value SLb set according to the vehicle speed VSP is set as a basic depression threshold value SLba (see step S207 in FIG. 4), and this is a correction coefficient corresponding to the gear position (gear ratio) at that time. The result corrected by K can be set as a post-depression threshold value SLa.

  The use of the post-depression threshold value SLa after the start position (depressing start position) of the clutch release operation is detected by the first clutch switch 16 forcibly makes the threshold SL smaller than before the depressing start position is detected. As a result, the threshold SL to be compared with the deviation ΔNE only needs to be smaller than before.

  When the threshold value SL to be compared with the deviation ΔNE is forcibly decreased in step S211, in the next step S212, the on / off state of the second clutch switch 17 indicates that the clutch pedal 9 is at the end position of the clutch release operation ( It is determined whether or not it corresponds to a state where it is depressed more than the stepping end position.

  For example, when the second clutch switch 17 is turned on when the clutch pedal 9 is not depressed, and is depressed to the clutch disengagement operation end position (depression end position) to be turned off, the step S212 is performed. Thus, it is determined whether or not the second clutch switch 17 is in an OFF state.

  Here, when it is determined by the second clutch switch 17 that the clutch pedal 9 has been depressed to the end position (stepping end position) of the clutch release operation, the release determination based on the determination result in step S214. Even if not, the clutch 2 is regarded as already released, and the process proceeds to step S215 as it is to determine whether the clutch 2 is released (forced release determination means).

  If it is determined by the second clutch switch 17 that the clutch pedal 9 has been depressed to the clutch release operation end position (stepping end position), the threshold value SL is set to 0, and then the step. By proceeding to S214, it is possible to determine whether or not to release the clutch 2 (see FIG. 5).

  On the other hand, when the clutch pedal 9 is not depressed to the end position (stepping end position) of the clutch release operation, that is, the depression position of the clutch pedal 9 is after the start position of the clutch release operation and before the end position. In this case, the process proceeds to step S213 so that the threshold value SL decreased in step S211 is compared with the deviation ΔNE to determine whether to release the clutch 2.

  That is, until the depression of the clutch pedal 9 is started, the engine speed NE caused by the accelerator closing shock is relatively determined according to the vehicle speed so as not to erroneously determine that it is caused by the clutch opening. Although a large threshold value SL is set, when the depression of the clutch pedal 9 is started, the threshold value SL is forcibly lowered so that the release of the clutch 2 is easily determined.

  In order to avoid erroneous determination that the engine rotation increase due to the shock caused by closing the accelerator in the engaged state of the clutch 2 is due to the release of the clutch 2, the threshold value SL is increased particularly in the low vehicle speed range. However, if the threshold value SL remains large, the increase in rotation due to the release of the clutch 2 cannot be specified, and the release determination of the clutch may become impossible.

  In the second embodiment, the start of depression of the clutch pedal 9 is detected, and even when the start of depression is not detected, if an increase in rotation exceeding the threshold SL is detected, the release of the clutch 2 is determined. Then, the control (for example, ignition timing correction for suppressing the increase in rotation speed) associated with the release of the clutch is performed.

  Thereby, even if the detection of the depression start position of the clutch pedal is delayed with respect to the actual release of the clutch 2, the release of the clutch 2 can be determined as distinguished from the accelerator close shock.

  When it is detected by the first clutch switch 16 that the depression of the clutch pedal 9 has been started, it is normally predicted that the clutch 2 will be released as it is, so that the threshold SL is lowered and the clutch is released. Is easily determined.

  Therefore, it is possible to prevent the clutch release determination from being greatly delayed or impossible to be determined while preventing the clutch release from being erroneously determined by the accelerator close shock particularly in the low vehicle speed range.

  Further, when the clutch pedal 9 is depressed to the end without making the determination of releasing the clutch 2 based on the increase in rotation, the release of the clutch 2 is determined regardless of the determination of the increase in rotation. Even if the accompanying increase in rotation cannot be detected, the release determination can be performed with the clutch 2 actually released.

  In a system in which the accelerator pedal and the throttle valve of the engine 1 are mechanically linked, the throttle valve opening is detected instead of detecting the accelerator opening, and the throttle valve is fully closed as an accelerator closed state. Can be made.

1 is a system diagram of a vehicle engine in an embodiment of the present invention. The flowchart which shows 1st Embodiment of the releasing / engagement determination of a clutch. The time chart which shows the characteristic of the open determination in the said 1st Embodiment. The flowchart which shows 2nd Embodiment of the releasing / engagement determination of a clutch. The time chart which shows the characteristic of the open determination in the said 2nd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Clutch, 3 ... Manual transmission, 4 ... Shift lever, 7 ... Engine control unit (threshold setting means, release determination means, threshold reduction means, forced release determination means), 9 ... Clutch pedal, 11 ... Accelerator pedal sensor (accelerator detection means), 12 ... Crank angle sensor (engine rotation detection means), 13 ... Vehicle speed sensor (vehicle speed detection means), 14 ... Shift position sensor (gear ratio detection means), 16 ... First clutch switch ( Opening start detecting means), 17 ... second clutch switch (opening end detecting means)

Claims (5)

In a vehicle in which rotational power of an engine is transmitted to wheels via a clutch and a transmission, a vehicle clutch state detection device for detecting engagement / release of the clutch,
Engine rotation detection means for detecting the rotation speed of the engine;
Vehicle speed detection means for detecting the vehicle speed;
Threshold setting means for setting a threshold based on the vehicle speed;
Accelerator detecting means for detecting a closed state of an accelerator for controlling the output of the engine;
An opening determining means for determining whether to release the clutch when the engine rotational speed has increased more than the threshold after the accelerator is closed;
Comprising
The vehicle threshold state detecting device , wherein the threshold value setting means sets the threshold value to a smaller value as the vehicle speed is higher . Comprising gear ratio detection means for detecting the gear ratio of the transmission;
It said threshold setting means, the vehicle speed and the claims 1 Symbol mounting for a vehicle clutch state detecting device and sets the threshold value based on the gear ratio. 3. The clutch state detecting device for a vehicle according to claim 2 , wherein the threshold value setting means sets the threshold value to a smaller value as the gear ratio is higher gear side. Release start detecting means for detecting the start of the clutch release operation;
Threshold lowering means for forcibly lowering the threshold when the start of clutch release operation is detected by the release start detecting means;
The vehicle clutch state detection device according to any one of claims 1 to 3 , wherein the vehicle clutch state detection device is provided. A disengagement end detecting means for detecting the end of the disengagement operation of the clutch;
Forced release determination means for determining release of the clutch in preference to the release determination means when the end of the clutch release operation is detected by the release end detection means;
The vehicle clutch state detection device according to any one of claims 1 to 4 , wherein the vehicle clutch state detection device is provided.

Images