JP6146250B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a vehicle control device.

  Conventionally, there are vehicles that can perform inertial running. For example, Patent Literature 1 includes an engine that serves as a power source for a vehicle, acceleration travel that accelerates the vehicle with power output from the engine, and inertial travel that causes the vehicle to travel by inertia without using power output from the engine. A technology of a vehicle control system capable of executing predetermined traveling control that alternately performs the vehicle within a predetermined speed range is disclosed.

  Patent Document 1 discloses a technique for releasing a clutch of a continuously variable transmission in coasting.

JP 2011-183963 A

  Here, when coasting control for releasing the clutch of the automatic transmission and running the vehicle is performed, if the return from coasting control and the shift are overlapped, acceleration operation is performed before the clutch is engaged. There is a possibility that the rotational speed will rise rapidly or a shock may occur due to sudden engagement of the clutch. It is desired to be able to appropriately execute a shift at the time of return from coasting control.

  An object of the present invention is to provide a vehicle control device capable of appropriately executing a shift at the time of return from coasting control.

  The vehicle control device of the present invention includes an automatic transmission disposed between the engine and the drive wheels, and a control unit that executes coasting control for releasing the clutch of the automatic transmission and causing the vehicle to travel. In the coasting control, when a return request from the coasting control occurs during the release of the clutch, an upshift of the automatic transmission is prohibited during the return from the coasting control.

  The vehicle control apparatus according to the present invention includes a control unit that executes coasting control for disengaging the clutch of the automatic transmission and causing the vehicle to travel, and a return request from the coasting control is generated during the coasting control while the clutch is being released. In this case, the upshift of the automatic transmission is prohibited during return from coasting control. According to the vehicle control device of the present invention, there is an effect that a shift at the time of return from coasting control can be executed at an appropriate timing.

FIG. 1 is a flowchart showing the operation of the vehicle control apparatus according to the embodiment. FIG. 2 is a skeleton diagram of the vehicle according to the embodiment. FIG. 3 is a diagram illustrating an operation engagement table of the automatic transmission according to the embodiment. FIG. 4 is an explanatory diagram of coasting control. FIG. 5 is a diagram illustrating a problem when an upshift is performed during return from coasting control. FIG. 6 is a time chart according to the operation of the vehicle control device of the embodiment. FIG. 7 is a diagram illustrating a problem caused by a shift during return from coasting control. FIG. 8 is another time chart relating to the operation of the vehicle control device of the embodiment.

  Hereinafter, a vehicle control device according to an embodiment of the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

[Embodiment]
The embodiment will be described with reference to FIGS. 1 to 8. The present embodiment relates to a vehicle control device. FIG. 1 is a flowchart showing the operation of the vehicle control device according to the embodiment of the present invention, FIG. 2 is a skeleton diagram of the vehicle according to the embodiment, and FIG. 3 is an operation engagement table of the automatic transmission according to the embodiment. FIG. 4 is an explanatory diagram of coasting control, FIG. 5 is a diagram illustrating a problem when upshifting during return from coasting control, and FIG. 6 is a time chart relating to the operation of the vehicle control device of the embodiment. FIG. 7 is a diagram showing a problem due to a shift during return from coasting control, and FIG. 8 is another time chart relating to the operation of the vehicle control device of the embodiment.

  As shown in FIG. 2, a vehicle 100 according to this embodiment includes an engine 1 and a vehicle control device 101. Further, the vehicle control device 101 of the present embodiment is configured to include the automatic transmission 3 and the ECU 50. The ECU 50 of this embodiment functions as a control unit that executes coasting control. In this specification, coasting control is control that causes the vehicle 100 to travel by releasing the clutch (first clutch C1 or second clutch C2) of the automatic transmission 3. In other words, coasting control is control that causes the vehicle 100 to travel by opening the engagement device of the automatic transmission 3 and interrupting transmission of power by the automatic transmission 3.

  The engine 1 is an example of an engine, and converts the combustion energy of fuel into a rotational motion of the rotating shaft 1a and outputs the converted rotational energy. The rotating shaft 1 a is connected to the input shaft 4 of the automatic transmission 3 via the torque converter 2.

  The torque converter 2 includes a pump impeller 2a, a turbine runner 2b, a stator 2c, a one-way clutch 2d, and a lock-up clutch 2e. The pump impeller 2 a is connected to the rotating shaft 1 a of the engine 1. The turbine runner 2 b is connected to the input shaft 4 of the automatic transmission 3. The torque converter 2 transmits torque by fluid transmission between the pump impeller 2a and the turbine runner 2b. The stator 2c has a function of amplifying torque. The one-way clutch 2d directly connects the rotary shaft 1a and the turbine runner 2b by engaging.

  The automatic transmission 3 is disposed between the engine 1 and the driving wheels of the vehicle 100, and shifts and outputs the rotation of the engine 1. The automatic transmission 3 is a planetary gear type stepped transmission that includes a first planetary gear mechanism 10, a second planetary gear mechanism 20, and a third planetary gear mechanism 30.

  The first planetary gear mechanism 10 is a single pinion type and includes a first sun gear 11, a first pinion gear 12, a first ring gear 13, and a first carrier 14. The first sun gear 11 is connected to the input shaft 4 and rotates integrally with the input shaft 4. The first ring gear 13 is disposed coaxially with the first sun gear 11 and radially outward of the first sun gear 11. The first pinion gear 12 meshes with the first sun gear 11 and the first ring gear 13. The first pinion gear 12 is rotatably supported by the first carrier 14. The first carrier 14 is rotatably supported coaxially with the input shaft 4.

  The second planetary gear mechanism 20 and the third planetary gear mechanism 30 constitute a Ravigneaux type differential mechanism 40 sharing a rotating element. The second planetary gear mechanism 20 is a single pinion type. The third planetary gear mechanism 30 is a double pinion type. The second planetary gear mechanism 20 includes a second sun gear 21, a second pinion gear 22, a second ring gear 23, and a second carrier 24. The second pinion gear 22 is rotatably supported by the second carrier 24.

  The third planetary gear mechanism 30 includes a third sun gear 31, an inner pinion gear 32a, an outer pinion gear 32b, a third ring gear 33, and a third carrier 34. The inner pinion gear 32a meshes with the third sun gear 31 and the outer pinion gear 32b. The outer pinion gear 32 b meshes with the inner pinion gear 32 a and the third ring gear 33. The inner pinion gear 32a and the outer pinion gear 32b are rotatably supported by the third carrier 34, respectively. The third sun gear 31 is connected to the first carrier 14 and rotates integrally with the first carrier 14.

  In the present embodiment, one rotating element serves as both the second pinion gear 22 and the outer pinion gear 32b. One rotating element also serves as the second ring gear 23 and the third ring gear 33. One rotating element also serves as the second carrier 24 and the third carrier 34. The second carrier 24 (third carrier 34) is an output shaft and is connected to the output gear 25. The output gear 25 is connected to drive wheels of the vehicle 100 via a differential mechanism or the like.

  The automatic transmission 3 has two clutches and three brakes as engagement devices. Each clutch C1, C2 and each brake B1, B2, B3 of this embodiment are friction engagement type engagement devices. The first clutch C <b> 1 connects and disconnects the input shaft 4 and the second sun gear 21. The second clutch C <b> 2 connects and disconnects the input shaft 4 and the second ring gear 23. The first brake B1 connects the first carrier 14 and the third sun gear 31 and the case 6 by being engaged, and restricts the rotation of the first carrier 14 and the third sun gear 31. The second brake B <b> 2 connects the second ring gear 23 and the third ring gear 33 and the case 6 by being engaged, and restricts the rotation of the second ring gear 23 and the third ring gear 33. The third brake B3 connects the first ring gear 13 and the case 6 by being engaged, and restricts the rotation of the first ring gear 13.

  The automatic transmission 3 has a one-way clutch F1. The one-way clutch F1 allows rotation of the second ring gear 23 and the third ring gear 33 in the forward direction and restricts rotation in the reverse direction. Here, the forward direction is the same direction as the rotation direction of the output gear 25 when the vehicle 100 travels forward, and the reverse direction is the direction opposite to the forward direction. In other words, the positive direction is the rotational direction of the input shaft 4 when it is rotationally driven by the torque of the engine 1.

  The vehicle 100 has a hydraulic control circuit 5. The hydraulic control circuit 5 controls the hydraulic pressure (clutch control pressure) supplied to the clutches C1 and C2 and the brakes B1, B2 and B3. Each clutch C1, C2 and each brake B1, B2, B3 are engaged or released according to the hydraulic pressure supplied by the hydraulic control circuit 5. The hydraulic control circuit 5 controls the hydraulic pressure supplied to the lockup clutch 2e.

  The automatic transmission 3 can shift forward 6 steps from 1st to 6th shown in FIG. 3 by a combination of disengagement and engagement of the clutches C1, C2 and brakes B1, B2, B3. In the operation engagement table shown in FIG. 3, the circles in the columns of the clutches C1, C2, the brakes B1, B2, B3 and the one-way clutch F1 indicate the engaged state, and the blanks indicate the released state.

  Returning to FIG. 2, the ECU 50 is an electronic control unit having a computer. The ECU 50 is electrically connected to the engine 1 and the hydraulic control circuit 5. The ECU 50 performs fuel injection control, throttle control, ignition control, and the like of the engine 1. The ECU 50 also outputs to the hydraulic pressure control circuit 5 the command value of the hydraulic pressure supplied to the clutches C1, C2, brakes B1, B2, B3, and lockup clutch 2e. That is, the ECU 50 also has a function as a shift control means for controlling the automatic transmission 3.

  The vehicle 100 includes an engine speed sensor 7, a turbine speed sensor 8, and an output shaft speed sensor 9. The engine speed sensor 7 detects an engine speed Ne that is the speed of the engine 1. The turbine speed sensor 8 detects a turbine speed Nt that is the speed of the turbine runner 2b. The output shaft rotational speed sensor 9 detects the rotational speeds of the second carrier 24 and the third carrier 34 that are output shafts.

  Each sensor 7, 8, 9 is electrically connected to the ECU 50 and outputs a signal indicating a detection result to the ECU 50. Further, the ECU 50 acquires detection results such as the accelerator opening, the brake operation amount, the oil temperature of the engine 1 and the automatic transmission 3, and the like.

  The ECU 50 stores in advance a shift line and a shift map that define a target shift stage according to a traveling state such as a vehicle speed and an accelerator opening. The ECU 50 makes a shift determination according to the traveling state based on the shift line and the shift map. When the ECU 50 determines to execute the shift according to the shift determination, the ECU 50 outputs a shift command to the target shift stage to the hydraulic control circuit 5. In response to the shift command, the hydraulic control circuit 5 releases the engagement device to be released at the target gear position among the clutches C1 and C2 and the brakes B1, B2, and B3. Engage.

  Moreover, ECU50 performs coasting control according to a driving | running | working state. When the execution condition for coasting control is established and the coasting control execution request is made, ECU 50 cuts off torque transmission by automatic transmission 3 and causes vehicle 100 to travel. Specifically, the ECU 50 shifts to coasting control by releasing the first clutch C1 or the second clutch C2 in accordance with the gear position of the automatic transmission 3. The bold line frame shown in FIG. 3 indicates an engagement device that is released by coasting control. As shown in FIG. 3, the first clutch C1 is disengaged at the time of executing the coasting control at the first gear (1st) to the fourth gear (4th). Also, at the fifth speed (5th) and the sixth speed (6th), the second clutch C2 is released when the coasting control is executed.

  When the first clutch C1 or the second clutch C2 is released, the power transmission from the input shaft 4 to the output gear 25 is cut off, and the automatic transmission 3 enters a state similar to that of the neutral (N). As a result, the engine brake does not act on the drive wheels, and the running resistance is reduced. Therefore, fuel efficiency can be improved by executing coasting control. In the present specification and drawings, the coasting control may be described as “N coasting”. Of the first clutch C1 and the second clutch C2, a clutch that is released by coasting control may be referred to as “N coasting clutch”.

  As described with reference to FIG. 4, the ECU 50 of the present embodiment performs the coasting control execution determination and the coasting control return determination according to, for example, the accelerator opening. FIG. 4 shows, in order from the top, the accelerator opening, the N coasting execution determination flag, the rotation speed, and the clutch control pressure. As the rotation speed, a turbine rotation speed Nt and an input shaft rotation speed Nin are shown. Here, the input shaft rotational speed Nin is not the actual rotational speed of the input shaft 4 but the output shaft rotational speed detected by the output shaft rotational speed sensor 9 and the gear ratio corresponding to the gear position of the automatic transmission 3. Is the number of rotations calculated based on When coasting control is executed and the first clutch C1 or the second clutch C2 is released, no power is transmitted in the automatic transmission 3, so the turbine rotational speed Nt and the input shaft rotational speed Nin deviate. The ECU 50 determines whether or not the clutch to be released is actually released based on the deviation amount, that is, the differential rotation speed.

  In FIG. 4, at time t1, the accelerator opening decreases to an opening indicating accelerator OFF, and the coasting control is determined to be executed. The ECU 50 turns on the N coasting execution determination flag and starts shifting to coasting control. The ECU 50 reduces the clutch control pressure for either the first clutch C1 or the second clutch C2 according to the current gear position. Here, a case where the first clutch C1 is released will be described as an example.

  As the clutch control pressure for the first clutch C1 decreases, the torque capacity of the first clutch C1 decreases, and the first clutch C1 is released via the slip state. Corresponding to the release of the first clutch C1, the turbine rotational speed Nt decreases with respect to the input shaft rotational speed Nin. The ECU 50 determines that the release of the first clutch C1 has been completed when the differential rotational speed between the input shaft rotational speed Nin and the turbine rotational speed Nt becomes equal to or greater than a certain value. In FIG. 4, it is determined that the release of the first clutch C1 is completed at time t2. The turbine speed Nt during the coasting control changes at a speed corresponding to the idle speed of the engine 1.

  At time t3, the accelerator is turned on, and a return determination from coasting control is made. The ECU 50 increases the clutch control pressure for the released clutch. For example, when the first clutch C1 is opened as an N coasting clutch, the clutch control pressure for the first clutch C1 is increased. When the first clutch C1 is engaged, the turbine rotational speed Nt increases toward the input shaft rotational speed Nin. When the turbine speed Nt is synchronized with the input shaft speed Nin, the ECU 50 determines that the complete engagement of the first clutch C1 is completed, and turns the N coasting execution determination flag OFF. In FIG. 4, when the N coasting execution determination flag is turned OFF at time t4, the return from coasting control is completed.

  Here, a shift request may be made during the coasting control. Since the coasting control involves the operation of releasing or engaging the N coasting clutch in the automatic transmission 3, it may not be preferable to perform a shift as described below with reference to FIG. .

  In FIG. 5, (a) is the accelerator opening, (b) is the rotational speed, (c) is the vehicle G, (d) is the gear shift, and (e) is the clutch control pressure. As the rotational speed, an engine rotational speed Ne and a turbine rotational speed Nt are shown. The vehicle G is an acceleration acting on the vehicle 100, for example, an acceleration in the front-rear direction of the vehicle 100. In the stage “(d) shift”, shift determination St and shift output Sc are shown. The shift determination St is a target shift speed based on the running state. The shift output Sc is a shift command output from the ECU 50 to the hydraulic control circuit 5. For example, if the shift output Sc is the fourth gear, the hydraulic control circuit 5 sets the clutches C1, C2 and the brakes B1, B2, B3 so that the gear of the automatic transmission 3 is the fourth gear. The clutch control pressure is controlled.

  As the clutch control pressure, a C1 pressure that is a clutch control pressure for the first clutch C1 and a C2 pressure that is a clutch control pressure for the second clutch C2 are shown. In FIG. 5, the execution of coasting control is started, and the C1 pressure starts to decrease at time t11. The gear shift output Sc at this time is the fourth gear, while the gear shift determination St is the fifth gear. In this case, it is assumed that an upshift to the fifth gear is executed at time t12 while the C1 pressure is decreasing. At the fifth speed, the first clutch C1 is released as shown in FIG. The hydraulic pressure control circuit 5 reduces the C1 pressure to 0 in order to shift from the fourth gear to the fifth gear.

  Here, the accelerator is turned on, and a return request from coasting control is generated at time t12. When the upshift is executed as described above and the C1 pressure is released during the return from the coasting control by the return request, the engine speed Ne is increased as described below.

  At the fifth speed, the second clutch C2 and the third brake B3 are engaged. After the C1 pressure is released, when the accelerator ON power is turned on without the clutch control pressure (apply actual pressure) of the third brake B3, one clutch is engaged (second clutch C2 for a moment). ) Or 0 free state. As a result, as shown in FIG. 5, the engine speed Ne increases rapidly and blows up.

  Further, the shift determination St changes from the fifth gear to the fourth gear at time t13 when the accelerator is turned on. When this downshift is executed, the release of the third brake B3 and the engagement of the first clutch C1 are executed. Due to the sudden engagement of the first clutch C1 from the state where the engine speed Ne has blown up, as shown by the arrow Y1, a large fluctuation of the vehicle G, that is, a shock occurs.

  On the other hand, in the vehicle control apparatus 101 according to the present embodiment, when a return request from the coasting control is generated in the middle of releasing the clutch in the coasting control, the upshift of the automatic transmission 3 is performed during the return from the coasting control. Is prohibited. Thereby, the vehicle control apparatus 101 can suppress the engine speed Ne from being blown up. In addition, the vehicle control device 101 prohibits an upshift during return from coasting control, so that a useless upshift is prepared in preparation for a case where the shift determination St subsequently changes to a low gear position (downshift request). Can be omitted and a shift shock can be suppressed.

  As shown in FIG. 6, when the vehicle control apparatus 101 of this embodiment releases the C1 pressure to shift to coasting control and the accelerator is turned on at time t21 and a return request is generated, During the return, upshifting of the automatic transmission 3 is prohibited. The ECU 50 prohibits upshifting to the fifth speed gear stage even if the current gear shift output Sc is the fourth speed gear stage and the gear shift determination St is the fifth speed gear stage. When the accelerator is turned on at time t21, the ECU 50 prohibits upshifting to the fifth gear, increases the C1 pressure while maintaining the fourth gear, and fully engages the first clutch C1. In the example shown in FIG. 6, the shift determination St changes to the fourth gear before the time t22 when the first clutch C1 is completely engaged, and the shift determination St matches the shift output Sc. Therefore, the return from coasting control is completed without the automatic transmission 3 being shifted. Thereby, it is possible to improve the responsiveness to the driver's acceleration request. If the shift determination St remains at the fifth gear after the first clutch C1 is fully engaged, an upshift to the fifth gear is permitted.

  With reference to FIG. 1, operation | movement of the vehicle control apparatus 101 of this embodiment is demonstrated. The control flow shown in FIG. 1 is executed while the vehicle 100 is traveling, and is repeatedly executed, for example, at predetermined intervals.

  In step S1, input information is collected by the ECU 50. The ECU 50 collects various types of information in order to determine the execution of coasting control. For example, accelerator opening, brake signal, oil temperature, etc. are acquired. When step S1 is executed, the process proceeds to step S2.

  In step S2, the ECU 50 determines whether or not the N coasting clutch is being released. In step S2, it is determined whether or not the coasting control is executed, and it is determined whether or not the N coasting clutch is being released. The ECU 50, for example, when the N coasting execution determination flag is ON, the clutch control pressure of the N coasting clutch is being reduced, and the difference between the turbine rotational speed Nt and the input shaft rotational speed Nin is equal to or less than a predetermined value. Then, it is determined that the clutch is being released. As a result of the determination in step S2, if it is determined that the N coasting clutch is disengaged (step S2-Y), the process proceeds to step S3. If not (step S2-N), the process proceeds to step S5.

  In step S3, the ECU 50 sets the N coasting clutch releasing flag flgA to ON. The N coasting clutch disengagement flag flgA is a flag that is turned ON when the N coasting clutch is disengaged. When step S3 is executed, the process proceeds to step S4.

  In step S4, the ECU 50 prohibits shifting. The ECU 50 prohibits any shift of upshift and downshift. When step S4 is executed, the control flow ends.

  In step S5, the ECU 50 determines whether or not the release of the N coasting clutch is completed. For example, when the difference between the turbine rotational speed Nt and the input shaft rotational speed Nin is greater than or equal to a predetermined value, the ECU 50 makes an affirmative determination in step S5. As a result of the determination in step S5, if it is determined that the N coasting clutch has been released (step S5-Y), the process proceeds to step S6. If not (step S5-N), the process proceeds to step S9.

  In step S6, the ECU 50 turns off the N coasting clutch releasing flag flgA. When step S6 is executed, the process proceeds to step S7.

  In step S7, the ECU 50 sets the N coasting clutch disengagement completion flag flgB to ON. The N coasting clutch disengagement completion flag flgB is a flag indicating that the disengagement of the N coasting clutch to be released by coasting control is completed. When step S7 is executed, the process proceeds to step S8.

  In step S8, the ECU 50 permits a shift. The ECU 50 permits the shift to the shift stage of the shift determination St and executes the shift. When step S8 is executed, the control flow ends.

  In step S9, the ECU 50 determines whether or not the N coasting clutch is engaged. The ECU 50 determines whether or not a return request from the coasting control is generated and the clutch is being engaged. For example, if the current gear position is the first to fourth gear speed and the first clutch C1 is released in coasting control, in step S9, the first clutch C1 is being engaged in response to the return request. It is determined whether or not. In this case, for example, when the clutch control pressure of the first clutch C1 is increasing and the turbine rotational speed Nt is not synchronized with the input shaft rotational speed Nin, the ECU 50 makes an affirmative determination in step S9. As a result of the determination in step S9, if it is determined that the N coasting clutch is engaged (step S9-Y), the process proceeds to step S10. If not (step S9-N), the process proceeds to step S14.

  In step S10, the ECU 50 determines whether or not the N coasting clutch disengagement flag flgA is ON. As a result of the determination, if it is determined that the N coasting clutch disengaged flag flgA is ON (step S10-Y), the process proceeds to step S11. If not (step S10-N), the process proceeds to step S12.

  In step S11, the upshift is prohibited by the ECU 50. The ECU 50 prohibits execution of the upshift even if the shift determination St is a value that requires the upshift. When step S11 is executed, the control flow ends.

  In step S12, the ECU 50 determines whether or not the N coasting clutch disengagement completion flag flgB is ON. As a result of the determination in step S12, if it is determined that the N coasting clutch disengagement completion flag flgB is ON (step S12-Y), the process proceeds to step S13. If not (step S12-N), the process proceeds to step S14. move on.

  In step S13, the ECU 50 prohibits gear shifting. The ECU 50 prohibits any upshift or downshift. When step S13 is executed, this control flow ends.

  Thus, the vehicle control apparatus 101 according to the present embodiment engages the N coasting clutch even when the N coasting clutch is engaged from the state where the N coasting clutch has been released (S12-Y). If it is halfway (S9-Y), gear shifting is prohibited. Thereby, as will be described below with reference to FIGS. 7 and 8, it is possible to suppress the engine speed Ne from being blown up.

  FIG. 7 shows a situation in which an upshift from the fourth gear to the fifth gear is made during coasting control, and a downshift request from the fifth gear to the fourth gear is made immediately thereafter. Has been. The release of the N coasting clutch is completed at time t31, and an upshift to the fifth gear is started based on the shift determination St. Here, the N coasting clutch at the fourth gear is the first clutch C1, whereas the N coasting clutch at the fifth gear is the second clutch C2. Therefore, when upshifting from the fourth gear to the fifth gear during coasting control, the C2 pressure is reduced and the B3 pressure, which is the clutch control pressure of the third brake B3, is increased. Further, the first clutch C1 remains open.

  Before the B3 pressure rises sufficiently, the accelerator pedal is depressed, and a return request from coasting control occurs at time t32. After that, when the shift determination St is switched to the fourth gear at the time t33, if the downshift is permitted as it is, the C1 pressure and the C2 pressure are released, and the B3 pressure is released before the B3 pressure is sufficiently increased. End up. As a result, the automatic transmission 3 enters a free state, causing a sudden increase in the engine speed Ne. Further, after that, the sudden engagement of the first clutch C1 causes an engagement shock as indicated by an arrow Y2.

  On the other hand, the vehicle control apparatus 101 according to the present embodiment prohibits a new shift until the N coasting clutch is completely engaged during the return from the coasting control. Thereby, as will be described with reference to FIG. 8, the engine speed Ne is prevented from rising. In FIG. 8, the release of the first clutch C1, which is an N coasting clutch, is completed at time t41. Thereafter, an upshift to the fifth speed shift stage, which is the shift determination St, is started.

  In FIG. 8, at time t42, the return from coasting control is started by turning on the accelerator. If the ECU 50 is in the process of returning from the coasting control, the ECU 50 does not permit the next shift until the upshift to the fifth gear and the complete engagement of the N coasting clutch are completed. For example, even if the shift determination St is switched to the fourth speed shift stage, the ECU 50 does not allow the next shift until the B3 pressure is completely engaged, and the second clutch C2, which is an N coasting clutch, is fully engaged. The next shift is not allowed until. When complete engagement of the second clutch C2 is completed at time t43, the ECU 50 permits the next shift. Thereby, it is possible to suppress the engine speed Ne from being blown up and to suppress the occurrence of a shock due to the sudden engagement of the clutch. When step S13 is executed, this control flow ends.

  In step S14, the ECU 50 permits a shift. That is, the shift is permitted when the return from the coasting control is completed (step S9-N). When step S14 is executed, the process proceeds to step S15.

  In step S15, the ECU 50 sets the N coasting clutch disengagement flag flgA and the N coasting clutch disengagement completion flag flgB to OFF. When step S15 is executed, this control flow ends.

  According to the vehicle control apparatus 101 according to the present embodiment, for example, during a change of mind such as re-depressing immediately after the accelerator is returned, an instantaneous clutch both-hands-off state is avoided, and the engine speed Ne is increased and increased. It is possible to suppress the engagement shock due to sudden grabbing.

  In addition, the structure of the automatic transmission 3 of this embodiment is an example, and the automatic transmission 3 of another structure may be employ | adopted. Further, the N coasting clutch released in the coasting control is appropriately determined according to the configuration of the automatic transmission 3. Further, the automatic transmission 3 may not only determine the target shift speed according to the running state but also switch the target shift speed according to the driver's shift operation.

  Further, the start condition of coasting control and the return condition from coasting control are not limited to those exemplified in the present embodiment.

  The contents disclosed in the above embodiments can be executed in appropriate combination.

1 Engine (Engine)
2 Torque Converter 3 Automatic Transmission 4 Input Shaft 5 Hydraulic Control Circuit 10 First Planetary Gear Mechanism 20 Second Planetary Gear Mechanism 30 Third Planetary Gear Mechanism 50 ECU (Control Unit)
100 vehicle 101 vehicle control device C1 first clutch C2 second clutch Sc shift output St shift determination

Claims (1)

An automatic transmission arranged between the engine and the drive wheels;
Control means for releasing coasting of the automatic transmission and executing coasting control for running the vehicle by cutting off power transmission between the engine and the drive wheels ;
In the coasting control, when a return request from the coasting control is generated while releasing the clutch, an upshift of the automatic transmission is prohibited during the return from the coasting control.

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