JP6485373B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a vehicle control device that controls a vehicle that performs inertial running while keeping a clutch open.

  2. Description of the Related Art Conventionally, there is known a clutch-by-wire system in which a clutch actuator is controlled by an electronic control unit in accordance with a clutch depression amount detected by a clutch pedal stroke sensor that detects a clutch depression amount.

  For example, Patent Document 1 compares a first control amount that is manually controlled according to a signal from a clutch pedal sensor with a second control amount that is automatically controlled according to an operation state, and compares the first control amount and the first control amount. A clutch-by-wire system that controls the clutch actuator according to a control amount on the non-engagement side of the two control amounts is described.

  In order to improve fuel efficiency in the above-described technique, there is a case where inertial running is performed with the clutch in an open state when the accelerator pedal is in an off state and the clutch pedal is in an off state while the vehicle is running. Further, when the vehicle is coasting, the engine may be further stopped to perform free-run traveling.

JP 2010-270804 A

  However, when a clutch pedal stroke sensor (hereinafter referred to as a stroke sensor) is in an abnormal state, there is a possibility that the clutch may shift to an engaged state under the control of an electronic control unit (ECU) based on a signal from the stroke sensor. is there. If the clutch is engaged while the vehicle is coasting or free-running (hereinafter, generically referred to as coasting), an engine brake is applied to the vehicle. In this case, if the same control as the clutch engagement control is performed with the stroke sensor in a normal state, the driver may unexpectedly feel a sense of deceleration or a sense of discomfort.

  The present invention has been made in view of the above, and an object of the present invention is when the clutch pedal sensor is in an abnormal state and the clutch is engaged while the vehicle is coasting with the clutch open. An object of the present invention is to provide a vehicle control device that can suppress a driver from feeling a sense of deceleration or discomfort.

  In order to solve the above-described problems and achieve the above object, a vehicle control device according to the present invention includes an engine, a transmission, and a drive that drives the transmission in a power transmission path that transmits power output from the engine. A clutch provided between the wheels, a clutch pedal for operating an open state and an engaged state of the clutch, a clutch pedal sensor for detecting a depression amount of the clutch pedal, and the clutch detected by the clutch pedal sensor A control unit that controls the state of the clutch based on the amount of depression of the pedal, and in the vehicle control device that controls the vehicle, the control unit is configured to perform the inertial running while running with the clutch in an open state. When the clutch pedal sensor is in an abnormal state, the clutch is moved forward under the normal state of the clutch pedal sensor. And controlling to engage in a time longer than the time to engage the clutch when returning from coasting to normal running.

  According to the vehicle control device of the present invention, when the clutch pedal sensor is in an abnormal state, the clutch is engaged for a longer time than the time required to engage the clutch when the clutch pedal sensor is in a normal state. Therefore, it is possible to lengthen the time from coasting to the engagement of the clutch. Therefore, in coasting traveling of the vehicle with the clutch open, the clutch pedal sensor becomes abnormal and the clutch is engaged. When combined, it is possible to suppress the driver from suddenly feeling a sense of deceleration or discomfort.

FIG. 1 is a diagram illustrating a configuration of a vehicle including a vehicle control device according to an embodiment of the present invention. FIG. 2 is a flowchart for explaining a control method by the vehicle control apparatus according to the embodiment of the present invention. FIG. 3 is a graph showing the basic clutch pedal stroke and the control state of the clutch actuator when the clutch pedal stroke sensor is in a normal state. FIG. 4 is a graph showing the amount of depression of the clutch pedal and the control state of the clutch actuator when the vehicle is coasting. FIG. 5 is a graph showing the amount of depression of the clutch pedal, the control state of the clutch actuator, and the acceleration of the vehicle when the clutch pedal stroke sensor is in an abnormal state during inertial running of the vehicle. FIG. 6 is a block diagram showing the configuration of the ECU and the input and output of the ECU according to an embodiment of the present invention. FIG. 7 shows the depression amount of the clutch pedal, the control state of the clutch actuator, and the acceleration of the vehicle when the clutch pedal stroke sensor is in an abnormal state, which is controlled by the vehicle control device according to the embodiment of the present invention. It is a graph. FIG. 8 is a block diagram illustrating a configuration of a control unit according to a first modification of the embodiment. FIG. 9 is a block diagram illustrating a configuration of a control unit according to a second modification of the embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In all the drawings of the following embodiment, the same or corresponding parts are denoted by the same reference numerals. Further, the present invention is not limited to the embodiment described below.

  First, a vehicle control device according to an embodiment of the present invention will be described. FIG. 1 shows a configuration of a vehicle including a vehicle control device according to this embodiment.

  As shown in FIG. 1, the vehicle Ve according to this embodiment includes an engine 1, a clutch 2, a transmission 3, an ECU 60, and a check lamp 70. The vehicle control apparatus 100 according to this embodiment is configured to be able to control the engine 1, and includes a clutch 2, a clutch actuator 23 for operating the clutch 2, and an ECU 60. The vehicle control apparatus 100 further includes an engine speed sensor 41, an input shaft speed sensor 42, an accelerator pedal sensor 43, a clutch pedal stroke sensor 44 (hereinafter referred to as a stroke sensor 44), an upper switch 45a, and a lower switch 45b. .

  The engine 1 functions as a power source for the vehicle Ve. The engine 1 is configured to be startable by driving a starter 11. After starting, the engine 1 converts the combustion energy of the fuel into a rotational motion of the output shaft 1a and outputs the rotational motion. The output shaft 1 a is connected to the input shaft 3 a of the transmission 3 through the clutch 2.

  The clutch 2 is disposed in a power transmission path between the engine 1 and the input shaft 3 a of the transmission 3. The clutch 2 operates the clutch actuator 23 in response to an input from the clutch pedal 24 by the driver, and connects or disconnects the transmission of power between the engine 1 and the input shaft 3a. The clutch 2 is, for example, a friction engagement type clutch device, and includes an input side engagement member 21 and an output side engagement member 22.

  The input side engaging member 21 is connected to the output shaft 1 a of the engine 1. The output side engagement member 22 is connected to the input shaft 3 a of the transmission 3. The clutch 2 transmits power between the engine 1 and the input shaft 3a when the input side engaging member 21 and the output side engaging member 22 are engaged by the clutch actuator 23. On the other hand, the clutch 2 blocks the transmission of power between the engine 1 and the input shaft 3a when the input side engaging member 21 and the output side engaging member 22 are separated by the clutch actuator 23 to be opened. The clutch 2 can be operated from the vehicle Ve side while the clutch actuator 23 is controlled by the ECU 60 while being engaged or disengaged by a driver's operation input to the clutch pedal 24.

  The transmission 3 is, for example, a manual transmission that changes gears by a driver's operation input to a shift lever. The transmission 3 has an input shaft 3a, an output shaft 3b, and a synchronization device (not shown). The transmission 3 is a constantly meshed transmission, and has a plurality of forward gear pairs 31 and a reverse gear pair that are always meshed. Each of the forward gear pairs 31 forms a gear stage having a different gear ratio. The synchronization device has a synchronization mechanism that synchronizes the rotation of the input shaft 3a and the rotation of the output shaft 3b in conjunction with a shift operation on the shift lever. For example, the synchronization device selectively engages one of the gear pairs 31 to synchronize the rotation of the input shaft 3a and the rotation of the output shaft 3b, whereby the input shaft 3a and the output shaft 3b by the gear pair 31 are synchronized. Connect power transmission with. The output shaft 3 b of the transmission 3 is engaged with the pinion gear 33 and the diffring gear 34, and is connected to the left and right drive wheels 5 via the differential mechanism 4. The power of the engine 1 output to the output shaft 3b is transmitted to the drive wheels 5 via the pinion gear 33, the diff ring gear 34, and the differential mechanism 4.

  The ECU 60 as the control unit is physically an electronic circuit mainly composed of a known microcomputer including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), an interface, and the like. Each function of the above-described ECU 60 loads various application programs held in the ROM into the RAM and executes them by the CPU, thereby operating various devices in the vehicle Ve under the control of the CPU, and in the RAM and ROM. This is realized by reading data and writing to RAM.

  In this embodiment, the ECU 60 is connected to various sensors such as an engine speed sensor 41, an input shaft speed sensor 42, an accelerator pedal sensor 43, a stroke sensor 44, and an upper switch 45a and a lower switch 45b of the clutch pedal 24. Yes.

  The engine speed sensor 41 is a sensor that detects the speed of the engine 1. The input shaft rotational speed sensor 42 is a sensor that detects the rotational speed of the input shaft 3 a in the transmission 3. The accelerator pedal sensor 43 is a sensor that detects the amount of depression of an accelerator pedal (not shown) operated by the driver. These detection result signals are sequentially supplied to the ECU 60 when the vehicle Ve travels.

  The stroke sensor 44 detects the amount by which the clutch pedal 24 is depressed. The ECU 60 controls the degree of engagement of the clutch 2 by operating the clutch actuator 23 based on a signal input from the stroke sensor 44. Therefore, the ECU 60 can also detect the degree of engagement of the clutch 2 based on the signal input from the stroke sensor 44. The upper switch 45a is a switch that is turned on when the clutch pedal 24 is not depressed. On the other hand, the lower switch 45b is a switch that is turned on when the clutch pedal 24 is fully depressed. That is, the upper switch 45a is turned on when the depression amount of the clutch pedal 24 in the stroke sensor 44 is minimum (for example, 0), and the lower switch 45b is turned on when the depression amount of the clutch pedal 24 is maximum.

  The ECU 60 is connected to the check lamp 70. When the ECU 60 determines that the stroke sensor 44 is abnormal by a method described later, the ECU 60 turns on the check lamp 70. Further, the ECU 60 calculates a required torque (requested driving force) to be transmitted to the drive wheels 5 based on conditions such as the vehicle speed and the accelerator opening, and controls the engine 1 based on the calculation result.

  A vehicle control processing method including the vehicle control device according to the embodiment configured as described above will be described. FIG. 2 is a flowchart for explaining a control processing method of the vehicle control apparatus according to the embodiment. Note that the flowchart of the control processing method described below is repeatedly executed at predetermined time intervals while the vehicle Ve is traveling.

  As shown in FIG. 2, in step ST1, the ECU 60 determines whether or not an abnormality has occurred in the stroke sensor 44, that is, whether or not the stroke sensor 44 has failed. The detection of abnormality in the stroke sensor 44 is performed based on the detection results of the upper sensor 45a and lower switch 45b in the clutch pedal 24 and the stroke sensor 44, for example. Specifically, there is a case where the depression amount of the clutch pedal 24 detected by the stroke sensor 44 is a minimum, for example, 0 even though the upper switch 45a is OFF. The same applies to the case where the depression amount of the clutch pedal 24 detected by the stroke sensor 44 is the maximum even though the lower switch 45b is OFF. That is, there is a contradiction between the on / off state of the upper switch 45a and the lower switch 45b and the depression amount of the clutch pedal 24 detected by the stroke sensor 44.

  When the ECU 60 determines that the stroke sensor 44 is not abnormal (step ST1: No), the control process according to this embodiment is terminated. On the other hand, when the ECU 60 determines that the stroke sensor 44 is abnormal (step ST1: Yes), the process proceeds to step ST2. In step ST2, the ECU 60 turns on the check lamp 70. As a result, it is possible to notify the outside that an abnormality has occurred in the stroke sensor 44.

  In step ST3, the ECU 60 determines whether or not the vehicle Ve is traveling inertially. In this specification, inertial traveling is not only inertial traveling in which the engine 1 is in a driving state and the clutch 2 is in an open state, but also in the state in which the engine 2 is not driven and the clutch 2 is in an open state. Including free-run driving. When the ECU 60 determines that the vehicle Ve is not coasting (step ST3: No), the control process according to this embodiment is terminated. On the other hand, when the ECU 60 determines that the vehicle Ve is traveling inertially (step ST3: Yes), the process proceeds to step ST4.

  In step ST4, the ECU 60 restarts the engine 1 by controlling and driving the starter 11. Here, if the clutch 2 is engaged while the engine 1 is stopped, the engine 1 may start to rotate during the engagement operation of the clutch 2 and the firing may be started. In this case, there is a possibility that the acceleration G of the vehicle Ve greatly changes due to the start of the firing of the engine 1 and a shock occurs. Therefore, in this embodiment, in order to moderate the change of the acceleration G based on the engagement operation of the clutch 2, the engine 1 is started in advance by the starter 11 or the like before the clutch 2 is engaged. Thereafter, the process proceeds to step ST5.

  In step ST5, the ECU 60 executes the engagement operation of the clutch 2 by the clutch actuator 23 in a longer time than when the stroke sensor 44 is in a normal state. In other words, the moving speed of the input side engaging member 21 and the output side engaging member 22 in the clutch 2 is made smaller than the moving speed when the stroke sensor 44 is normal. Thereby, the clutch 2 is engaged slowly. The ECU 60 slowly engages the clutch 2 by operating the clutch actuator 23 and performs fuel cut (fuel cut: F / C). As a result, the vehicle Ve is shifted to the engine brake state. Thus, the control process according to this embodiment is completed.

  Next, the specific control method of step ST5 in the control processing method described above will be described based on the detection state of the stroke sensor 44 and the operation state of the clutch actuator 23. FIG. 3 is a graph showing the detection state of the stroke sensor 44 and the operation state of the clutch actuator 23 when performing basic clutch control. FIG. 4 shows the detection state of the stroke sensor 44 and the operating state of the clutch actuator 23 from immediately before the inertial travel request is turned on by the ECU 60 until the inertial travel request is turned off and the control returns to the basic control. It is a graph. FIG. 5 is a graph showing the detection state of the stroke sensor 44, the operation state of the clutch actuator 23, and the acceleration G of the vehicle Ve when the stroke sensor 44 is in an abnormal state in the prior art. FIG. 6 is a diagram illustrating the configuration of the ECU 60 according to the embodiment, and the input and output of the ECU 60. FIG. 7 is a graph showing the detection state of the stroke sensor 44, the operating state of the clutch actuator 23, and the acceleration G of the vehicle Ve when the stroke sensor 44 is in an abnormal state in this embodiment.

  As shown in FIG. 3, in normal basic clutch control, the intermediate state between the disengaged state in which the depression amount of the clutch pedal 24 detected by the stroke sensor 44 is the maximum and the engaged state in which it is the minimum (for example, 0). (Half-engaged state) may occur (time T11 to T12). In this case, the operation amount of the clutch actuator 23 is also an intermediate state between the released state and the engaged state of the clutch 2. Thereafter, when the amount of depression of the clutch pedal 24 is minimized at times T12 to T13, the clutch 2 is engaged by the operation of the clutch actuator 23. Furthermore, as shown in time T13 to T14, when the clutch pedal 24 is depressed and the amount of depression reaches the maximum from the minimum, the clutch 2 is released by the operation of the clutch actuator 23. That is, in basic clutch control, the clutch actuator 23 is operated according to the operation amount of the clutch pedal 24, and the clutch 2 is in the released state, the semi-engaged state, or the engaged state.

  As shown in FIG. 4, at time T <b> 21, when ECU 60 determines that a predetermined condition for coasting is satisfied, ECU 60 turns on the coasting travel request. The predetermined condition for coasting is when the driving force is not requested during traveling, such as when both the clutch pedal 24 and the accelerator pedal (not shown) are off. From time T21 to T22, the ECU 60 controls the clutch actuator 23 to switch the clutch 2 from the engaged state to the released state. After that, even if the depression amount of the clutch pedal 24 is the smallest and the depression amount detected by the stroke sensor 44 is the smallest, while the predetermined inertial running condition is satisfied (time T22 to T23), the ECU 60 operates the clutch actuator. 23 is controlled to maintain the clutch 2 in the released state.

  After that, at time T23, when a condition for returning from inertia traveling to normal traveling is satisfied, for example, an accelerator pedal (not shown) is turned on, the inertia traveling request is turned off. In this case, during a period of time T23 to T24, the ECU 60 controls the clutch actuator 23 to operate, thereby switching the clutch 2 from the released state to the engaged state. After time T24, the vehicle Ve returns to normal running, and the control of the clutch 2 by the ECU 60 returns to the basic clutch control described above.

  A case will be described in which the stroke sensor 44 breaks down and enters an abnormal state during inertial traveling (time T22 to T23) shown in FIG. As shown in FIG. 5, it is assumed that the stroke sensor 44 has failed at time T31. When the stroke sensor 44 breaks down, the ECU 60 engages the clutch 2 in order to continue traveling or by recognizing that the upper switch 45a is on and the operator requests engagement of the clutch 2. Control to match. For example, it is erroneously detected that the clutch pedal 24 is depressed. As a result, the ECU 60 determines that the inertia travel request has been turned off, and controls the clutch actuator 23 to engage the clutch 2 in the same manner as the times T23 to T24 shown in FIG.

  However, in the clutch control according to the prior art shown in FIG. 5, since the inertia brake is suddenly shifted to the state where the engine brake is applied between the start of engagement of the clutch 2 (time T32) and the completion of engagement (time T33). The acceleration G of the vehicle Ve changes abruptly. Further, since the clutch is switched from the disengaged state to the engaged state in a state where the driver does not desire to return from the inertia traveling to the normal traveling, an engine brake which the driver does not desire acts on the vehicle Ve. The person may feel a sudden slowdown and feel a strong sense of incongruity.

  On the other hand, in step ST5 (see FIG. 2) in the control processing method according to this embodiment described above, the clutch 2 is engaged in a longer time compared to the clutch control according to the prior art. Here, as shown in FIG. 6, the ECU 60 has a calculation unit 60a, and when a request driving force signal, an engine rotation speed Ne detection signal, and an input shaft rotation speed Nin detection signal are input, the calculation unit. 60a outputs an actuator target value for controlling the clutch actuator 23. The clutch actuator 23 is operated based on the actuator target value output from the ECU 60, and the engagement and release of the clutch 2 are controlled.

  Specific control based on the actuator target value will be described. In other words, as shown in FIG. 7, it is assumed that the stroke sensor 44 has failed and entered an abnormal state at time T41. In this embodiment, the ECU 60 detects that the stroke sensor 44 is in an abnormal state (see step ST1 in FIG. 2). Then, at time T42, the ECU 60 operates the clutch actuator 23 for a time (time T42 to T43) longer than the time T32 to T33 described above to shift the clutch 2 from the released state to the engaged state. That is, the actuator target value is a value such that the clutch 2 is engaged during the time T42 to T43. Here, the time required for clutch control according to the prior art is the time required for engagement of the clutch 2 in the same vehicle Ve when the stroke sensor 44 returns to normal driving from normal driving in a normal state where the stroke sensor 44 has not failed. is there. That is, the longer time compared to the clutch control according to the prior art means that the clutch 2 in the abnormal state is compared with the time required for the engagement of the clutch 2 in the normal state with the stroke sensor 44 in the same vehicle Ve. It means that the time required for engagement is long.

  In this case, as shown in the graph of the acceleration G of the vehicle in FIG. 7, the acceleration G of the vehicle slowly increases in the deceleration direction as the clutch actuator 23 engages the clutch 2. As a result, it is possible to suppress a state in which the driver feels deceleration and feels uncomfortable.

  According to the embodiment of the present invention described above, when the stroke sensor 44 fails and becomes in an abnormal state, the clutch 2 is engaged from the disengaged state in a longer time than the control of the clutch 2 according to the prior art. By shifting to the state, it is possible to lengthen the time for the vehicle Ve to shift from the inertia traveling to the state where the engine brake is applied, and therefore, a rapid change in the acceleration G of the vehicle Ve can be reduced. It is possible to suppress a state in which the driver feels sudden deceleration and feels uncomfortable.

(First modification)
Next, a first modification of the vehicle control device according to the embodiment described above will be described. FIG. 8 is a block diagram showing a configuration of the ECU 60 according to the first modification. As shown in FIG. 8, the ECU 60 includes a calculation unit 60b. Data of the engine speed Ne and data of the target speed of the engine 1 are input to the calculation unit 60b. Then, the proportional gain (P gain) is set so that the value in the abnormal state in which the stroke sensor 44 has failed is smaller than the value in the normal state in which the stroke sensor 44 has not failed. Thus, the ECU 60 controls the clutch 2 by setting the actuator control value so that the clutch actuator 23 operates more slowly than usual. Even in this case, the same effect as that of the above-described embodiment can be obtained.

(Second modification)
Next, a second modification of the vehicle control device according to the above-described embodiment will be described. FIG. 9 is a block diagram showing a configuration of the ECU 60 according to the second modification. As shown in FIG. 9, the ECU 60 includes a calculation unit 60a and a smoothing processing unit 60c according to an embodiment. As described above, the required driving force signal, the engine rotation speed Ne detection signal, and the input shaft rotation speed Nin detection signal are input to the arithmetic unit 60a. The calculation unit 60a outputs an actuator target value for controlling the clutch actuator 23 based on the input data. Furthermore, the actuator target value output from the calculation unit 60a and the actual value of the clutch actuator 23 are input to the annealing processing unit 60c. The annealing processing unit 60c performs an annealing process calculation on the input actuator target value based on the actual actuator value. As a result, the actuator control value for which the smoothing process has been executed is output for the actuator target value. Thus, the ECU 60 controls the clutch 2 by setting the actuator control value so that the clutch actuator 23 operates more slowly than usual. Even in this case, the same effect as that of the above-described embodiment can be obtained.

  Although one embodiment of the present invention has been specifically described above, the present invention is not limited to the above-described embodiment, and various modifications based on the technical idea of the present invention are possible. For example, the numerical values given in the above-described embodiment are merely examples, and different numerical values may be used as necessary.

2 Clutch 23 Clutch actuator 24 Clutch pedal 44 Clutch pedal stroke sensor (stroke sensor)
45a Upper switch 45b Lower switch 60 ECU
60a, 60b arithmetic unit 60c annealing processing unit

Claims (1)

An engine, a transmission, a clutch provided between the transmission and a drive wheel in a power transmission path for transmitting power output from the engine, and a clutch for operating an open state and an engaged state of the clutch A vehicle, comprising: a pedal; a clutch pedal sensor that detects a depression amount of the clutch pedal; and a control unit that controls a state of the clutch based on the depression amount of the clutch pedal detected by the clutch pedal sensor. In the vehicle control device
When the clutch pedal sensor is in an abnormal state during inertial traveling while traveling with the clutch open, the control unit normally moves the clutch from the inertial traveling under the normal state of the clutch pedal sensor. A vehicle control device that controls to engage in a longer time than the time to engage the clutch when returning to traveling.

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