Vehicle control device

Abstract

To provide a control device of a vehicle which can exactly determine a finish of the synchronization of a transmission.SOLUTION: When a shift operation to a gear change stage in which a forward direction is inverted is performed during the traveling of a vehicle (YES in a step S2), an ECU determines that the synchronization of a transmission 4 has been finished (step S11) when a rotation number coincides with a target synchronization rotation number (YES in a step S9) after the rotation number is dropped once to an inversion confirmation rotation number or lower (YES in a step S5). The inversion confirmation rotation number is set to a value smaller than the target synchronization rotation number. The inversion confirmation rotation number is value which is obtained by subtracting a prescribed first speed difference from the target synchronization rotating number, and when a rotation number difference between a rotation number of a clutch 7 and the target synchronization rotation number reaches a second speed difference or smaller which is smaller than the first speed difference, the ECU determines that the synchronization of the transmission 4 has been finished.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a vehicle control device. [Background technology]

[0002] Patent Document 1 describes a control device for a vehicle equipped with a belt-type CVT (continuously variable transmission) connected to an internal combustion engine via a forward clutch of a forward / reverse switching device, which determines that the forward clutch is engaged when the detected rotation speed of the input shaft and the rotation speed of the output shaft of the forward clutch match, including the direction of rotation, and determines a belt transmission torque command value for the CVT according to the determination result, thereby reducing the output torque of the engine. As a result, the device described in Patent Document 1 can accurately determine the engagement state of the clutch. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-090931 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a vehicle equipped with a clutch between a parallel shaft gear type transmission and an engine, the clutch must be engaged after synchronization of the synchronization mechanism (synchronizing mechanism) inside the transmission is completed. In other words, before the clutch is engaged and the transmission of driving force begins, the synchronization of the synchronization mechanism must be completed and a gear stage must be established so that the gear rotates integrally with the shaft. The completion of synchronization can be determined when the number of rotations (rotational speed) of the clutch matches the number of rotations (target synchronous rotation speed) determined by the gear ratio of the gear stage to be synchronized and the vehicle speed, including the direction of rotation.

[0005] However, while there is no problem with the synchronization determination in a transmission as described above if the configuration is capable of detecting the rotation direction of each rotating element, such as the vehicle control device described in Patent Document 1, the following problems arise in a configuration that uses inexpensive sensors that cannot detect the rotation direction of each rotating element.

[0006] In other words, in a configuration in which the rotational direction of each rotating element cannot be detected, when determining synchronization of the transmission, there is a risk of erroneously determining that synchronization is complete in a situation where each rotating element rotates in different directions at the same rotational speed.

[0007] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide a vehicle control device that can accurately determine completion of synchronization of a transmission even in a configuration that uses inexpensive sensors. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention provides a control device for a vehicle that includes a transmission in which power is transmitted from an engine via a clutch and in which gears can be changed by a shift operation, and a control unit that determines that synchronization of the transmission is complete when the rotational speed of the clutch matches a predetermined target synchronous rotational speed that is determined based on the gear to be changed to and the vehicle speed, and is characterized in that, when a shift operation to a gear that reverses the direction of travel is performed while the vehicle is traveling, the control unit determines that synchronization of the transmission is complete when the rotational speed once drops below a predetermined reversal confirmation rotational speed and then matches the target synchronous rotational speed. Effect of the Invention

[0009] In this way, according to the present invention, it is possible to provide a vehicle control device that can accurately determine completion of synchronization of the transmission. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of a vehicle according to an embodiment of the present invention. [Diagram 2]FIG. 2 is a flowchart showing a procedure of a synchronization completion determination operation for a vehicle according to one embodiment of the present invention. [Diagram 3] FIG. 3 is a time chart showing the transition of the vehicle state when the synchronization completion determination operation is performed by the vehicle control device according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] A vehicle control device according to one embodiment of the present invention is a vehicle control device comprising: a transmission in which power is transmitted from an engine via a clutch and in which gears can be changed by a shift operation; and a control unit that determines that synchronization of the transmission is complete when the rotational speed of the clutch matches a predetermined target synchronous rotational speed determined based on the gear to be changed to and the vehicle speed, wherein when a shift operation to a gear in which the direction of travel is reversed is performed while the vehicle is traveling, the control unit determines that synchronization of the transmission is complete when the rotational speed drops below a predetermined reversal confirmation rotational speed and then matches the target synchronous rotational speed.

[0012] This allows the control device for a vehicle according to one embodiment of the present invention to accurately determine completion of synchronization of the transmission. EXAMPLES

[0013] A vehicle equipped with a control device according to an embodiment of the present invention will be described in detail below with reference to the drawings. Note that the rotational speed used in the following description indicates the rotational speed (rpm).

[0014] In FIG. 1, a vehicle 1 according to one embodiment of the present invention is configured to include an engine 2, a motor generator 3 for driving, a transmission 4, a differential 5, drive wheels 6, and an ECU (Electronic Control Unit) 10 as a control unit.

[0015] A plurality of cylinders are formed in the engine 2. In this embodiment, the engine 2 is configured to perform a series of four strokes, which are an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke, for each cylinder.

[0016] An ISG (Integrated Starter Generator) 20 is connected to the engine 2. The ISG 20 is connected to the crankshaft of the engine 2 via a belt 21 or the like. The ISG 20 has a function as an electric motor that rotates when supplied with electric power to drive the engine 2, and a function as a generator that converts the rotational force input from the crankshaft into electric power.

[0017] The motor generator 3 functions as an electric motor that generates driving force for the vehicle using power supplied from a battery 31 via an inverter 30, and also functions as a generator that generates regenerative electricity using the rotational force (reverse driving force) input from the drive wheels 6 via a differential 5.

[0018] Under the control of the ECU 10, the inverter 30 converts DC power supplied from the battery 31 into three-phase AC power and supplies it to the motor generator 3, and also converts the three-phase AC power generated by the motor generator 3 into DC power to charge the battery 31. The battery 31 is formed of a secondary battery such as a lithium ion battery.

[0019] The transmission 4 changes the speed of the rotation input from the engine 2 to the input shaft 8 via the clutch 7 at a speed ratio corresponding to one of a plurality of gear stages, and outputs the rotation from the output shaft 9. In this embodiment, the transmission 4 is configured as an AMT (Automated Manual Transmission) that automates the gear shifting operation based on the structure of a parallel shaft gear type manual transmission. In detail, the transmission 4 is a transmission that can perform gear shifting automatically, or can be operated by the driver using a shift lever 40 or a clutch pedal 71 described later, like a so-called manual transmission. Hereinafter, for ease of explanation, the forward gear stages are referred to as D range (1 / 2 / 3 / 4 / 5 / 6 gear stages), and the reverse gear stage is referred to as R range (reverse gear stage).

[0020] The gear stages of the transmission 4 are changed by a shift actuator 44. The shift actuator 44 is connected to and controlled by the ECU 10. An output shaft 9 of the transmission 4 is connected to left and right drive wheels 6 via a differential 5. An output shaft of the motor generator 3 is connected to the output shaft 9 of the transmission 4. In this manner, the vehicle 1 is configured as a hybrid vehicle that can run using the driving force of at least one of the engine 2 and the motor generator 3.

[0021] The gears that can be established in the transmission 4 include, for example, forward gears (D range) ranging from 1st gear, which is a low gear, to 6th gear, which is a high gear, and reverse gears (R range). The number of gears for driving varies depending on the specifications of the vehicle 1, and is not limited to the above-mentioned 1st gear to 6th gear. The transmission 4 is provided with a synchronization mechanism (synchro mesh) not only for the forward gears but also for the reverse gears.

[0022] The gears in the transmission 4 can be changed according to the operating position of a shift lever 40 operated by the driver. The operating position of the shift lever 40 is detected by a shift position sensor 41. The shift position sensor 41 is connected to the ECU 10 and transmits the detection result to the ECU 10.

[0023] In this embodiment, the operating positions of the shift lever 40 include a P range which is a parking position, an R range which is a reverse position, an N range which is a neutral position, and a D range which is a forward position.

[0024] For example, when the driver sets the shift lever 40 to the D range, the ECU 10 drives the shift actuator 44 and the clutch actuator 70 in response to the detection signal of the accelerator opening sensor 91, etc., to shift between each of the forward gear stages from 1st to 6th gear.

[0025] Furthermore, when the driver shifts the shift lever 40 from the D range to the R range, the ECU 10 drives the shift actuator 44 and the clutch actuator 70 to change the gear from the forward gear to the reverse gear.

[0026] The D range and R range in this embodiment are shift positions at which the vehicle can run, and constitute the running positions of the present invention. The P range and N range are shift positions at which the engine 2 can be started, and constitute the starting positions of the present invention.

[0027] The transmission 4 is provided with a neutral switch 42. The neutral switch 42 is connected to the ECU 10. The neutral switch 42 detects a state in which no gear is established in the transmission 4, that is, a neutral state, and is turned on when the transmission 4 is in a neutral state.

[0028] A clutch 7 is provided in the power transmission path between the engine 2 and the transmission 4. For example, a dry single-plate friction clutch can be used as the clutch 7. The engine 2 and the transmission 4 are connected via the clutch 7.

[0029] In this way, the transmission 4 is configured such that power is transmitted from the engine 2 to the input shaft 8 via the clutch 7, and the gears can be changed by a shift operation. The clutch 7 is equipped with a clutch disc, and the clutch disc and the input shaft 8 of the transmission 4 are interconnected and rotate integrally. Therefore, the rotation speed of the clutch disc (hereinafter referred to as the rotation speed of the clutch 7) is equal to the rotation speed of the input shaft 8 of the transmission 4.

[0030] The clutch 7 is operated by a clutch actuator 70 and can be switched between an engaged state in which power is transmitted between the engine 2 and the transmission 4, a released state in which power is not transmitted, and a half-clutch state in which torque is transmitted with a rotational difference. The clutch actuator 70 is connected to the ECU 10 and is controlled by the ECU 10.

[0031] The clutch 7 is provided with a rotation speed sensor 43, which detects the rotation speed of the clutch 7. The rotation speed sensor 43 is connected to the ECU 10 and transmits the detection result to the ECU 10. However, the rotation speed sensor 43 is an inexpensive sensor that cannot detect the rotation direction of the clutch 7.

[0032] The ECU 10 controls the clutch actuator 70 in response to the depression amount of the clutch pedal 71 operated by the driver, and controls the clutch 7 to operate in the same manner as a manual clutch. Furthermore, the ECU 10 controls the clutch actuator 70 regardless of the operation of the clutch pedal 71 by the driver, and can change the state of the clutch 7.

[0033] The amount of depression of the clutch pedal 71 is detected by a clutch pedal sensor 72. The clutch pedal sensor 72 is connected to the ECU 10 and transmits a signal corresponding to the amount of depression of the clutch pedal 71 to the ECU 10.

[0034] The vehicle 1 is equipped with an accelerator pedal 90 that is operated by the driver. The amount of depression of the accelerator pedal 90 is detected by an accelerator opening sensor 91. The accelerator opening sensor 91 is connected to the ECU 10, detects the amount of depression of the accelerator pedal 90 as an accelerator opening, and transmits a signal corresponding to the accelerator opening to the ECU 10.

[0035] The vehicle 1 is equipped with a brake pedal 92 that is operated by the driver. The amount of depression of the brake pedal 92 is detected by a brake pedal sensor 93. The brake pedal sensor 93 is connected to the ECU 10 and transmits a signal corresponding to the amount of depression of the brake pedal 92 to the ECU 10.

[0036] The ECU 10 is composed of a computer unit having a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory for storing backup data, etc., an input port, and an output port.

[0037] The ROM of the computer unit stores various constants, various maps, and the like, as well as a program for causing the computer unit to function as the ECU 10. That is, the CPU executes the program stored in the ROM using the RAM as a working area, causing the computer unit to function as the ECU 10 in this embodiment.

[0038] In addition to the above-mentioned sensors, a vehicle speed sensor 11 is connected to the ECU 10. The vehicle speed sensor 11 detects the speed of the vehicle 1 and transmits the detection result to the ECU 10.

[0039] The ECU 10 is adapted to switch the control mode of the vehicle 1. In this embodiment, an EV mode and an HEV mode are set as the control modes.

[0040] The EV mode is a control mode in which the clutch 7 is in a released state and the vehicle 1 is driven by the power of the motor generator 3. The HEV mode is a control mode in which the clutch 7 is in an engaged state and the vehicle 1 is driven by the power of the engine 2, or the engine 2 and the motor generator 3.

[0041] The ECU 10 switches between the EV mode and the HEV mode based on, for example, the accelerator opening and the engine speed.

[0042] For example, when the driver requested torque determined by the accelerator opening exceeds the HEV transition threshold during driving in the EV mode, the ECU 10 restarts the engine 2 and transitions to the HEV mode.

[0043] For example, when the driver requested torque determined by the accelerator opening and the engine speed falls below the EV shift threshold while driving in the HEV mode, the ECU 10 stops the engine 2 and shifts to the EV mode.

[0044] When switching the internal gear position of the transmission 4, the ECU 10 drives the clutch actuator 70 to release the clutch 7, thereby changing the gear position of the transmission 4.

[0045] The ECU 10 determines that synchronization of the transmission 4 is complete when the rotation speed of the clutch 7 matches a predetermined target synchronous rotation speed determined based on the gear position to which the transmission 4 is changed and the vehicle speed. Then, the ECU 10 engages the clutch 7 after determining that synchronization of the transmission 4 is complete.

[0046] Here, the target synchronous speed refers to the rotation speed of the clutch 7 calculated from the rotation speed of the drive wheels 6 of the vehicle 1 in motion, taking into consideration the gear ratio of the power transmission path, such as the differential 5 and the transmission 4. In other words, the target synchronous speed refers to the rotation speed of the input shaft 8 and the clutch 7 when the gear constituting the power transmission path to be changed during the gear shift operation, while the drive wheels 6 are rotating, becomes the same rotation speed as the shaft due to the action of the synchronization mechanism, and is the rotation speed of the input shaft 8 and the clutch 7 calculated backwards from the rotation speed of the drive wheels 6.

[0047] Note that, when engaging the clutch 7, the ECU 10 can also control the engine 2 so that the engine speed becomes the target synchronous speed. This allows the clutch 7 to be smoothly engaged in a state where the engine speed matches the speed of the clutch 7.

[0048] In this embodiment, the transmission 4 is equipped with a synchronization mechanism not only for the forward gear but also for the reverse gear, so that the transmission 4 can be switched to the reverse gear even when the vehicle 1 is not stopped.

[0049] For this reason, in a situation where the vehicle 1 is parked in a garage, even if the driver switches the range to R while the vehicle 1 is moving slowly forward in D range, the ECU 10 switches the transmission 4 to a gear for reverse. Similarly, even if the driver switches the range to D while the vehicle 1 is moving slowly backward in R range, the ECU 10 switches the transmission 4 to a gear for forward.

[0050] For example, when the transmission 4 is shifted from a forward gear to a reverse gear, the rotation speed of the released clutch 7 gradually decreases due to the action of the synchronization mechanism, the rotation stops instantaneously, and then the rotation direction is reversed. After that, the rotation speed of the clutch 7 in the reverse direction increases and reaches a predetermined target synchronous rotation speed, completing synchronization of the reverse gear.

[0051] If the completion of synchronization is determined by referring only to the rotation speed of the clutch 7 when a gear shift is performed in which the rotation direction of the clutch 7 is reversed, a situation will occur in which the rotation direction of the clutch 7 is different but the rotation speed matches the target synchronous rotation speed, resulting in an erroneous determination that synchronization is complete. If it is erroneously determined that synchronization is complete, the clutch 7 will be engaged even though synchronization is not complete, placing a large load on the synchronization mechanism and causing a large shock to the vehicle 1.

[0052] Therefore, in this embodiment, when a shift operation to a gear stage in which the direction of travel is reversed is performed while the vehicle is traveling, the ECU 10 determines that synchronization of the transmission 4 is complete when the rotational speed of the clutch 7 drops temporarily below a predetermined reversal confirmation rotational speed and then matches the target synchronous rotational speed.

[0053] In other words, in this embodiment, when a shift operation to a gear ratio that reverses the direction of travel is performed while the vehicle is traveling, the condition for determining whether synchronization is complete is added that the rotation speed of the clutch 7 has temporarily dropped below a predetermined reversal confirmation rotation speed.

[0054] In this embodiment, the reversal confirmation rotation speed is set to a value smaller than the target synchronous rotation speed. More specifically, the reversal confirmation rotation speed is set to a value (rotation speed) obtained by subtracting a predetermined first speed difference from the target synchronous rotation speed. The reversal confirmation rotation speed is set to a sufficiently small rotation speed so that it can be confirmed that the rotation speed of the clutch 7 has once dropped to 0 rpm and the rotation direction has reversed (reversed). In other words, the reversal confirmation rotation speed is a value that can reliably confirm that the rotation speed has dropped below the target synchronous rotation speed, and is determined taking into consideration the time required to reliably detect the drop in the rotation speed to the 0 rpm side that always passes during reverse rotation that is lower than the reversal confirmation rotation speed.

[0055] Then, the ECU 10 determines that synchronization of the transmission 4 is complete when the rotation speed difference between the rotation speed of the clutch 7 and the target synchronous rotation speed becomes equal to or less than a second speed difference that is smaller than the first speed difference. In other words, even if the rotation speed of the clutch 7 does not completely match the target synchronous rotation speed, the ECU 10 determines that synchronization of the transmission 4 is complete when the difference between the rotation speeds becomes small enough to be considered to match.

[0056] The synchronization completion determination operation performed by the control device according to this embodiment configured as above will be described with reference to Fig. 2. This synchronization completion determination operation is repeatedly performed at short intervals when the transmission 4 is shifted.

[0057] In step S1, the ECU 10 determines whether or not the gear shift operation is in the synchronous phase, and ends the current operation if the gear shift operation is not in the synchronous phase. The synchronous phase refers to the operation of the synchronization mechanism when switching the gear position of the transmission 4. On the other hand, if the gear shift operation is in the synchronous phase, the ECU 10 proceeds to step S2 and determines whether or not the gear shift operation is a range change operation (R→D, D→R) based on the driver's shift lever operation.

[0058] If the operation is not a range change (R→D, D→R) operation based on the driver's shift lever operation, the ECU 10 proceeds to step S3 and uses a conventional synchronization determination, ending the current operation. The conventional synchronization determination is a method of determining that synchronization of the transmission 4 is complete when the rotation speed of the clutch 7 matches the target synchronization rotation speed. On the other hand, if the operation is a range change (R→D, D→R) operation based on the driver's shift lever operation, the ECU 10 proceeds to step S4 and determines whether the current vehicle speed is equal to or greater than a predetermined value V. Here, the predetermined value V is a speed at which the vehicle can be considered to be almost stopped, and is set to a speed at which the synchronization mechanism can instantly complete synchronization.

[0059] If the vehicle speed is not equal to or greater than the predetermined value V, synchronization can be completed without placing a burden on the synchronization mechanism, so the process proceeds to step S3, where the conventional synchronization determination is used, and the current operation is terminated. On the other hand, if the vehicle speed is equal to or greater than the predetermined value V, the ECU 10 proceeds to step S5, where it calculates the target synchronous rotation speed.

[0060] Next, the ECU 10 determines whether or not the clutch rotation speed reduction determination has been established in step S6. Here, the ECU 10 determines whether or not the determinations in steps S7 and S8 in the previous control cycle were YES and the flag "the clutch rotation speed reduction determination has been established" in step S9 has been set.

[0061] If the clutch rotation speed drop determination has not been established in step S6, the ECU 10 determines in step S7 whether a predetermined time has elapsed since the clutch rotation speed was equal to or less than the target synchronous rotation speed minus threshold 1 as the first speed difference. That is, in step S7, the ECU 10 determines whether the rotation speed of the clutch 7 has once dropped to or below a predetermined reversal confirmation rotation speed as a clutch rotation speed drop determination. Furthermore, by checking whether the dropped state has continued for a predetermined time, the drop in rotation can be determined more reliably without being affected by signal abnormalities or the like.

[0062] If the determination in step S7 is YES, the ECU 10 determines in step S9 that the clutch rotational speed decrease determination is established, sets a flag indicating that the determination is established, and ends the current operation.

[0063] On the other hand, if the condition in step S7 is not satisfied, the ECU 10 determines in step S8 whether a predetermined time has elapsed during which the clutch rotation speed exceeds the target synchronous rotation speed minus threshold value 1 (i.e., the clutch rotation speed does not fall below the subtracted value), and terminates the current operation if this condition is not satisfied.

[0064] On the other hand, if the condition in step S8 is satisfied, the ECU 10 determines in step S9 that the clutch rotation speed reduction determination is satisfied, sets a flag indicating that the determination is satisfied, and ends this operation. Step S8 is executed as a timeout determination to prevent the control from being stopped.

[0065] If the clutch rotation speed reduction determination has been established in step S5, the ECU 10 determines in step S10 whether the clutch rotation speed is equal to or greater than the target synchronous rotation speed minus threshold 2 as the second speed difference and equal to or less than the target synchronous rotation speed plus threshold 2 for a predetermined time, and if this condition is satisfied, the ECU 10 determines in step S11 that synchronization is complete and ends the current operation. In this way, the ECU 10 determines that synchronization of the transmission 4 is complete when the rotation speed of the clutch 7 falls within the range of the second speed difference for the positive and negative of the target synchronous rotation speed for a predetermined time. Then, the ECU 10 engages the clutch 7 after determining that synchronization of the transmission 4 is complete.

[0066] The transition of the vehicle state when such a synchronization completion determination operation is performed will be described with reference to Fig. 3. The vertical axis of Fig. 3 represents, from the top, the shift position of the shift lever 40, the vehicle speed, the gear shift state, the clutch position (the engagement state of the clutch 7), and the clutch rotation speed, while the horizontal axis represents the transition of time. The gear shift state represents the state related to the switching of the internal gear stages of the transmission 4.

[0067] In the initial state at time t0, the shift lever 40 is set to the D range, and the vehicle 1 is traveling forward in HEV mode using the engine 2 at a speed equal to or greater than a predetermined speed V. In addition, the transmission 4 is not in a gear shifting state, and the clutch 7 is engaged.

[0068] After that, at time t1, the driver switches the shift lever 40 to the R range, which initiates a shift of the gear position and causes the clutch 7 to begin to be released.

[0069] Then, at time t2, the clutch 7 is released and the gear shift state starts to disengage from the forward gear stage. Then, at time t3, the gear shift state completes disengagement and enters the select state, and at time t4, the select state is completed and the gear engagement operation starts.

[0070] Here, disengaging gears refers to the movement of the operating parts inside the transmission 4 in the shift direction from the gear before the shift to neutral. Selecting refers to the movement of the operating parts in the select direction to a position related to the destination gear. Engaging gears refers to the movement of the operating parts in the shift direction to the destination gear. Synchronization of the synchronization mechanism is performed by starting the gear engagement operation, and when synchronization is completed, a power transmission path in the transmission 4 is established.

[0071] At time t2, the clutch 7 is released and the gear disengagement is completed, causing the clutch rotation speed to drop due to loss of driving force, and at time t4, the synchronization mechanism begins to synchronize, braking the rotation and causing the rotation speed to drop rapidly. Then, at time t5, the clutch rotation speed drops to the reversal confirmation rotation speed, and then continues to drop further, dropping to 0 rpm. After that, the clutch 7 reverses the rotation direction and the rotation speed increases, rising above the reversal confirmation rotation speed at time t6.

[0072] After that, at time t7, the clutch rotation speed almost coincides with the target synchronous rotation speed, it is determined that synchronization of the transmission 4 is complete, and gear engagement is completed. The completion of synchronization is determined when the clutch rotation speed is within a speed difference range of a predetermined threshold value 2 above and below the target synchronous rotation speed. Then, from time t7 when synchronization is completed, the clutch 7 begins to engage. As a result, the shifting state of the transmission 4 becomes a state where shifting is not in progress (a state where the transmission is not in the synchronous phase). In addition, as the clutch 7 begins to engage and the driving force of the engine 2 is gradually transmitted, the forward speed of the vehicle 1 decreases, and then the vehicle switches to reverse, and the vehicle speed becomes a speed according to the gear ratio of the shift stage to which the shift is changed, etc.

[0073] At time t8, the engagement of the clutch 7 is completed. At this time t8, the control related to the gear shift ends, the vehicle speed is a negative value indicating the reverse direction, and the vehicle 1 moves backward.

[0074] As described above, in this embodiment, when a shift operation to a gear ratio in which the traveling direction is reversed is performed while the vehicle is traveling, the ECU 10 determines that synchronization of the transmission 4 is complete when the rotational speed of the clutch 7 drops temporarily below a predetermined reversal confirmation rotational speed and then matches the target synchronous rotational speed.

[0075] As a result, for example, when the driver performs a shift operation from D range to R range while the vehicle is traveling, the ECU 10 of this embodiment can determine that a shift operation to a gear stage that reverses the traveling direction has been performed while the vehicle is traveling. Then, when the rotation speed of the clutch 7 temporarily drops below a predetermined reversal confirmation rotation speed and then resumes rotation, the ECU 10 determines that the rotation speed of the clutch 7 has started to rotate in the reverse direction. After that, when the rotation speed of the clutch 7 matches the target synchronous rotation speed, the ECU 10 determines that synchronization of the transmission 4 has been completed.

[0076] This prevents the erroneous determination that synchronization of the transmission 4 is complete because the rotation speed of the clutch 7 matches the target synchronous rotation speed even though the rotation direction of the clutch 7 is in the opposite direction. As a result, it is possible to accurately determine that synchronization of the transmission 4 is complete.

[0077] In this embodiment, the reversal confirmation RPM is set to a value smaller than the target synchronous RPM, so that the RPM of the clutch 7 is once set to a value smaller than the target synchronous RPM, and synchronization can be determined after the rotation direction of the clutch 7 is reversed.

[0078] The reversal confirmation rotation speed is set to a rotation speed faster than the rotation speed of the input shaft 8 and the clutch 7 calculated backwards from the rotation speed of the drive wheels 6 corresponding to the predetermined vehicle speed value V. As a result, even if it is difficult to detect the moment when the rotation speed of the clutch 7 becomes 0 rpm and reverses, the ECU 10 can detect that the rotation speed has dropped to a sufficiently low speed, such as near 0 rpm, at which the reversal of the rotation direction of the clutch 7 can be confirmed.

[0079] Furthermore, in this embodiment, the reversal confirmation rotation speed is a value obtained by subtracting a predetermined first speed difference from the target synchronous rotation speed, and the ECU 10 determines that synchronization of the transmission 4 is completed when the rotation speed difference between the rotation speed of the clutch 7 and the target synchronous rotation speed becomes equal to or less than a second speed difference which is smaller than the first speed difference.

[0080] Thus, by setting the first speed difference to an appropriate value, the ECU 10 can reliably detect the reversal of the rotational direction of the clutch 7. Also, since the completion of synchronization of the transmission 4 can be determined when the rotation speed of the clutch 7 falls within the range of the second speed difference in both the positive and negative directions with respect to the target synchronous rotation speed, the completion of synchronization of the transmission 4 can be determined quickly.

[0081] Although an embodiment of the invention has been disclosed, it will be apparent to one of ordinary skill in the art that modifications may be made thereto without departing from the spirit and scope of the invention, and it is intended that all such modifications and equivalents be included in the following claims. [Explanation of symbols]

[0082] 1 vehicle 2 Engine 4-speed 7. Clutch 10 ECU (control unit)

Claims

1. A transmission in which power is transmitted from an engine via a clutch and in which gears can be changed by a shift operation; A control unit that determines that synchronization of the transmission is completed when the rotation speed of the clutch coincides with a predetermined target synchronous rotation speed determined based on a shift stage to which the transmission is changed and a vehicle speed, The control unit determines that synchronization of the transmission is completed when a shift operation to a gear stage in which the direction of travel is reversed is performed while the vehicle is traveling, and when the rotational speed temporarily drops below a predetermined reversal confirmation rotational speed and then matches the target synchronous rotational speed.

2. 2. The vehicle control device according to claim 1, wherein the reversal confirmation rotation speed is set to a value smaller than the target synchronous rotation speed.

3. the reversal confirmation rotation speed is a value obtained by subtracting a predetermined first speed difference from the target synchronous rotation speed, 3. The vehicle control device according to claim 1, wherein the control unit determines that synchronization of the transmission is completed when a rotational speed difference between the rotational speed and the target synchronous rotational speed becomes equal to or less than a second speed difference that is smaller than the first speed difference.

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