JP2017089691A - Control device of automatic transmission for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of an automatic transmission for a vehicle which can suppress a shock generated at a restart of an engine after the engine is stopped, in the vehicle which stops the engine during the stop of the vehicle for the purpose of the improvement of the fuel economy of the vehicle, and has a function for bringing the automatic transmission into a neutral state.SOLUTION: In a period that an engine 30 is transited to complete explosion from initial explosion, a clutch C1 of an automatic transmission 12 for a vehicle which is engaged with the engine 30 is brought into a slip state. During the transition of the initial explosion at which engine torque is increased to the complete explosion, since the clutch C1 is slipped, a shock which is generated by the increase of the engine torque, and transmitted from the engine 30 can be suppressed.SELECTED DRAWING: Figure 5

Description

  The present invention relates to control of a vehicle having a vehicular automatic transmission, and relates to control of an engagement device of a vehicular automatic transmission at restart after an automatic engine stop.

  For the purpose of improving vehicle fuel efficiency, when the engine is stopped in a vehicle having a function of stopping the engine when the vehicle is in an idle state, for example, when stopping at an intersection or the like, the automatic transmission is a hydraulic engagement device. Is provided, oil pressure is not supplied from an oil pump that generates oil pressure by the driving force of the engine, and the oil pressure for controlling the automatic transmission is reduced. When the engine is restarted, hydraulic pressure is supplied from the oil pump by rotating the engine, and the engagement elements are engaged when the hydraulic pressure becomes sufficient. However, the engine was already at a high speed and shocked when the engagement element was fully engaged. On the other hand, in Patent Document 1, even when the engine is stopped and the hydraulic pressure is not supplied to the oil pump, the hydraulic pressure of the hydraulic unit of the automatic transmission is maintained by the check valve and the accumulator. A technique for reducing shock by engaging an engagement element of an automatic transmission before starting is disclosed.

Japanese Patent Laid-Open No. 08-014076

  By the way, in Patent Document 1, since the engagement element of the automatic transmission is engaged before the engine is started, compared with the case where the engagement element is engaged when the engine reaches a high speed. Can reduce the shock. However, since there is a variation in the torque characteristics at the initial explosion of each engine, a shock may occur when the engine is restarted, for example, when the difference in torque between the initial explosion and the complete explosion is large. there were.

  The present invention has been made against the background of the above circumstances. The purpose of the present invention is to improve the fuel consumption of the vehicle by stopping the engine while the vehicle is stopped and setting the automatic transmission to the neutral state. An object of the present invention is to provide a control device for an automatic transmission for a vehicle that can suppress a shock that occurs when the engine is restarted after the engine is stopped.

  The gist of the present invention is that in a vehicle including an engine and an automatic transmission, the engine is automatically stopped when a predetermined condition is satisfied, and the engagement element of the automatic transmission is released to release the automatic transmission. A control device for an automatic transmission for a vehicle that puts the machine in a neutral state and restarts the engine when a predetermined restart condition is satisfied, and engages the engagement element. In the initial explosion section of the engine, the engagement element of the automatic transmission for vehicle is engaged so that the standby torque capacity is higher than the engine torque at the time of the initial explosion by a predetermined value. The engagement pressure is increased while the slip of the engagement element is maintained from the start, and the engagement pressure is further increased after completion of the complete explosion of the engine, and the slip state is finished. It is in the making.

  In this way, the engagement element of the automatic transmission for the vehicle is in a slip state while the engine shifts from the first explosion to the complete explosion. While the engine transitions from the initial explosion to the complete explosion, the engagement element maintains the slip state, so that the shock transmitted from the engine based on the increase in engine torque is effectively suppressed, and after the complete explosion is completed. By further increasing the engagement pressure and completing the engagement, a shock transmitted from the engine can be suppressed.

1 is a skeleton diagram illustrating a configuration of an automatic transmission for a vehicle provided in a vehicle to which the present invention is applied. FIG. 2 is an operation table illustrating combinations of operation of engagement elements when a plurality of gear stages of the vehicle automatic transmission of FIG. 1 are established. It is a block diagram explaining the principal part of the electric control system provided in the vehicle in order to control the automatic transmission for vehicles of FIG. FIG. 4 is a circuit diagram relating to a linear solenoid valve that controls the operation of each hydraulic actuator for clutches and brakes in the hydraulic control circuit of FIG. 3. It is a functional block diagram explaining the principal part of the control function of the electronic control apparatus of FIG. It is a time chart explaining the principal part of the action | operation of an engine, a torque converter, and an engagement element at the time of the engagement apparatus of FIG. 1 switching from a half-engagement state to complete engagement with engine restart. FIG. 2 is a flowchart for explaining the main parts of the operation of the engine, the torque converter, and the engagement element when the engagement device of FIG. 1 is switched from a half-engaged state to a complete engagement as the engine is restarted.

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

  FIG. 1 is a skeleton diagram illustrating a schematic configuration of a vehicular automatic transmission 12 (hereinafter, abbreviated for a vehicle) provided in a vehicle 10 to which the present invention is applied. FIG. 2 is an operation table for explaining combinations of a plurality of hydraulic friction engagement devices when a plurality of gears of the automatic transmission 12 are established. The automatic transmission 12 is preferably used for an FF vehicle, and is a single pinion type first planetary gear device 16 in a transaxle case 14 (hereinafter referred to as a case 14) as a non-rotating member attached to a vehicle body. And a second transmission unit 24 configured as a Ravigneaux type mainly including a double pinion type second planetary gear unit 20 and a single pinion type third planetary gear unit 22. Are output on an output gear 28 that functions as an output member by shifting the rotation of the input shaft 26. The input shaft 26 corresponds to an input rotating member of the automatic transmission 12, and in this embodiment, a turbine of a torque converter 32 as a fluid transmission device that is rotationally driven by an engine 30 that is a driving force source for traveling. It is constructed integrally with the shaft. Further, the output gear 28 corresponds to an output rotating member of the automatic transmission 12, and in this embodiment, for example, meshes with the diff ring gear 36 in order to transmit power to the differential gear device 34 shown in FIG. The counter drive gears constituting the counter gear pair are engaged with the counter driven gear arranged coaxially with the differential drive pinion constituting the final gear pair. As shown in FIG. 3, the output of the engine 30 is driven to the left and right via the vehicle power transmission device 11 including the torque converter 32, the automatic transmission 12, the differential gear device 34, the pair of axles 38, and the like sequentially. It is transmitted to the wheel 40. The automatic transmission 12 and the torque converter 32 are substantially symmetrical with respect to the center line (axial center) C, and the lower half of the axial center C is omitted in the skeleton diagram of FIG.

  The torque converter 32 includes a lock-up clutch 42 that directly transmits the power of the engine 30 to the input shaft 26 without fluid. The lock-up clutch 42 is a hydraulic friction clutch that is frictionally engaged by a differential pressure ΔP between the hydraulic pressure in the engagement-side oil chamber 44 and the hydraulic pressure in the release-side oil chamber 46, and is completely engaged (locked). The power of the engine 30 is directly transmitted to the input shaft 26. Further, if necessary, the differential pressure ΔP, that is, the torque transmission capacity is feedback controlled so as to be engaged in a predetermined slip state.

  The automatic transmission 12 corresponds to the combination of any one of the rotation states (sun gears S1 to S3, carriers CA1 to CA3, ring gears R1 to R3) of the first transmission unit 18 and the second transmission unit 24. Six forward gear stages (forward shift stages) from the first gear stage “1st” to the sixth gear stage “6th” are established, and the reverse gear stage (reverse shift stage) of the reverse gear stage “R” is established. It is done. As shown in FIG. 2, for example, in the forward gear stage, the first speed gear stage (1st) is engaged by the engagement of the clutch C1 and the brake B2, and the second speed gear stage (2nd is engaged by the engagement of the clutch C1 and the brake B1. ), The engagement between the clutch C1 and the brake B3 causes the third speed gear stage (3rd) to be engaged, and the engagement between the clutch C1 and the clutch C2 causes the fourth speed gear stage (4th) to engage the clutch C2 and the brake B3. Accordingly, the fifth speed (5th) gear stage is established, and the sixth speed (6th) gear stage is established by engagement of the clutch C2 and the brake B1. Further, the reverse gear stage (R) is established by the engagement of the brake B2 and the brake B3, and the neutral state (N) is established by releasing any of the clutches C1, C2 and the brakes B1 to B3. It is configured. In the case 14, there is a mechanical oil pump 48 that is driven to rotate by the engine 30, and generates a working hydraulic pressure that becomes a source pressure for operating the clutches C 1 and C 2 and the brakes B 1 to B 3. Is provided. In this embodiment, the clutch C1 is generally called a starting clutch and corresponds to an engagement element.

  The operation table of FIG. 2 summarizes the relationship between the gear stages GS and the engagement elements, that is, the operation states of the clutches C1 to C2 and the brakes B1 to B3, and “◯” represents engagement. “X” indicates release. The clutches C1 and C2 and the brakes B1 to B3 (hereinafter simply referred to as the clutch C and the brake B unless otherwise distinguished) are controlled by a hydraulic actuator such as a multi-plate clutch or a brake. This is a hydraulic friction engagement device that transmits the motive power to the drive wheel 40 side. The clutch C and brake B are switched between engaged and disengaged states by excitation, de-excitation, and current control of the linear solenoid valves SL1 to SL5 (see FIGS. 3 and 4) in the hydraulic control circuit 100. The transient hydraulic pressure during release is controlled. Further, the accumulation of hydraulic pressure to the accumulator ACM and the supply of hydraulic pressure from the accumulator ACM to each hydraulic friction engagement device are switched by excitation, de-excitation, and current control of the on / off solenoid valve SV1.

  FIG. 3 is a block diagram for explaining a main part of an electrical control system provided in the vehicle 10 for controlling the engine 30, the automatic transmission 12, and the like. In FIG. 3, the vehicle 10 is provided with an electronic control device 120 including a hydraulic control device related to, for example, engine stop while the automatic transmission 12 is stopped and engine restart control. The electronic control device 120 includes a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like, for example. The CPU uses a temporary storage function of the RAM and stores a program stored in the ROM in advance. In accordance with the signal processing, the output control of the engine 30 and the shift control of the automatic transmission 12 are executed, and the engine control device for engine control and the linear in the hydraulic control circuit 100 are executed as necessary. The solenoid valves SL1 to SL5, SLT and the on / off solenoid valve SV1 are divided into hydraulic control devices for shift control and the like.

  The electronic control unit 120 includes, for example, a signal indicating the hydraulic oil temperature TOIL (° C.) that is the temperature of the hydraulic oil (for example, a known ATF) in the hydraulic control circuit 100 detected by the hydraulic oil temperature sensor 50, an accelerator opening sensor. A signal indicating the accelerator opening Acc (%), which is an operation amount of the accelerator pedal 54 as a required amount (driver required amount) for the vehicle 10 detected by the driver 52, an engine 30 detected by the engine speed sensor 56. , A signal representing the engine speed NE (rpm), the signal representing the cooling water temperature TW (° C.) of the engine 30 detected by the cooling water temperature sensor 58, and the intake of the engine 30 detected by the intake air amount sensor 60 A signal representing the air quantity Q / N, a throttle which is the opening of the electronic throttle valve detected by the throttle valve opening sensor 62. A signal representing the valve opening degree θTH (%), a signal representing the output rotational speed NOUT (rpm) which is the rotational speed of the output gear 28 corresponding to the vehicle speed V (km / h) detected by the vehicle speed sensor 64, a brake switch A signal indicating an operation (on) BON of the foot brake pedal 68 indicating that the foot brake, which is a service brake being operated (depressing operation), is detected by 66, a lever position of the shift lever 72 (detected by the lever position sensor 70). Operation position, shift position) Signal representing PSH, turbine rotational speed NT (rpm) which is the rotational speed of the turbine of the torque converter 32 detected by the turbine rotational speed sensor 74 (that is, input rotational speed which is the rotational speed of the input shaft 26) NIN) is supplied.

  In addition, the electronic control unit 120 outputs an engine output control command signal SE for controlling the output of the engine 30, for example, a drive signal to the throttle actuator for controlling the opening / closing of the electronic throttle valve in accordance with the accelerator opening Acc, and fuel An injection signal for controlling the fuel injection amount injected from the injection device, an ignition timing signal for controlling the ignition timing of the engine 30 by the igniter, and the like are output. Further, hydraulic control command signals SA, SP (SP1, SP2, SP3, SP4, SP5) for shifting control of the automatic transmission 12, for example, the gear stage GS of the automatic transmission 12 are switched in the hydraulic control circuit 100. Linear solenoid valve SLT for regulating the pressure of valve command signals (hydraulic command value, drive signal) and line oil pressure PL for controlling the excitation and non-excitation of linear solenoid valves SL1 to SL5 and on / off solenoid valve SV1 A driving signal is output.

  Further, the shift lever 72 is disposed, for example, in the vicinity of the driver's seat, and manually moves to five operation positions “P”, “R”, “N”, “D”, or “S” as shown in FIG. It is designed to be operated.

  The “P” position (range) is in a neutral state (neutral state) in which none of the gears in the automatic transmission 12 is established and the power transmission in the automatic transmission 12 is interrupted, and mechanically by a mechanical parking lock mechanism. This is a parking position (position) for preventing (locking) the rotation of the output gear 28. The “R” position is a reverse travel position (position) for establishing a reverse gear stage in which the rotation direction of the output gear 28 of the automatic transmission 12 is reverse. The “N” position is a neutral position (position) for achieving a neutral state in which power transmission in the automatic transmission 12 is interrupted. Further, the “D” position is a shift range (D range) that allows the automatic transmission 12 to change gears, and the automatic shift is performed using all the forward gears from the first gear stage “1st” to the sixth gear stage “6th”. This is the forward travel position (position) for executing the control. The “S” position is an engine brake position (position) at which manual shift can be performed by switching among a plurality of types of shift ranges that limit the change range of the gear steps, that is, a plurality of shift ranges with different gear ranges on the high vehicle speed side. is there.

  FIG. 4 shows the linear solenoid valves SL1 to SL5 that control the operation of the hydraulic actuators (hydraulic cylinders) ACT1 to ACT5 of the clutches C1 and C2 and the brakes B1 to B3 in the hydraulic control circuit 100, and the time when the engine 30 is stopped. It is a figure which shows the principal part of the hydraulic control circuit 100 regarding the on-off solenoid valve SV1 which controls the action | operation of the accumulator ACM which functions as a hydraulic pressure source.

  In FIG. 4, a hydraulic pressure supply device 102 is mechanically operated based on a regulator valve that regulates line hydraulic pressure using hydraulic pressure generated from a mechanical oil pump 48 that is rotationally driven by the engine 30 as well as operation of a shift lever 72. Alternatively, a manual valve or the like that electrically switches the oil passage is provided. For example, when the shift lever 72 is operated to the “D” position or the “S” position, the manual valve outputs the line oil pressure PL (MPa) input to the manual valve as the drive oil pressure PD (MPa), and the shift lever 72 When 72 is operated to the “R” position, the input line hydraulic pressure PL is output as a reverse hydraulic pressure PR (MPa), and when the shift lever 72 is operated to the “P” position or the “N” position, The output is shut off (the drive hydraulic pressure PD and the reverse hydraulic pressure PR are guided to the discharge side). In this manner, the hydraulic pressure supply device 102 outputs the line hydraulic pressure PL, the drive hydraulic pressure PD, and the reverse hydraulic pressure PR.

  In addition, the hydraulic control circuit 100 includes linear solenoid valves SL1 to SL5 (hereinafter referred to as linear solenoid valves SL unless otherwise specified) and on / off solenoid valves corresponding to the hydraulic actuators ACT1 to ACT5 and the accumulator ACM. SV1 is provided. The hydraulic actuators ACT1, ACT2, ACT3, ACT5, and the accumulator ACM are respectively supplied with the drive hydraulic pressure PD supplied from the hydraulic supply device 102 by the corresponding linear solenoid valves SL1, SL2, SL3, SL5, and the on-off solenoid valve SV1, respectively. The hydraulic pressures are adjusted to the hydraulic pressures PC1, PC2, PB1, PB3, and PACM (MPa) corresponding to the hydraulic control command signals SA and SP (SP1, SP2, SP3, SP4, and SP5) from the electronic control device 120, respectively, and directly. Supplied. The hydraulic actuator ACT4 directly adjusts the line hydraulic pressure PL supplied from the hydraulic pressure supply device 102 to the operating hydraulic pressure PB2 corresponding to the command signal from the electronic control device 120 by the corresponding linear solenoid valve SL4. Supplied. Note that either the hydraulic pressure PB3 or the reverse hydraulic pressure PR adjusted by the linear solenoid valve SL5 is supplied to the hydraulic actuator ACT5 of the brake B3 via the shuttle valve 112.

  The linear solenoid valves SL1 to SL5 have basically the same configuration, and the on / off solenoid valve SV1 is a solenoid valve that is driven on and off, and is individually excited, de-energized, and current controlled by the electronic control unit 120. The hydraulic pressure supplied to the hydraulic actuators ACT1 to ACT5 and the accumulator ACM that functions as a hydraulic pressure source when the engine 30 is stopped is independently regulated and the clutches C1 and C2, brakes B1 to B3, and the accumulator ACM are operated. The hydraulic pressure PC1, PC2, PB1, PB2, PB3 and PACM are respectively controlled. In the automatic transmission 12, for example, as shown in the operation table of FIG. 2, any two predetermined friction engagement devices are engaged to establish each gear stage GS. In the shift control of the automatic transmission 12, a so-called clutch-to-clutch shift is performed by, for example, re-engaging the disengagement side frictional engagement device and the engagement side frictional engagement device of the clutch C and brake B involved in the shift. The At the time of this clutch-to-clutch shift, the release transition hydraulic pressure of the release side frictional engagement device and the engagement side frictional engagement device are engaged so that the shift is executed as quickly as possible while suppressing the shift shock. Transient oil pressure is properly controlled. For example, the hydraulic control command signal SP1 is a signal that drives the linear solenoid valve SL1 that controls the engagement pressure of the clutch C1. The hydraulic control command signal SP4 is a signal for driving the solenoid valve SL4 that controls the engagement pressure of the brake B2.

  In the vehicle 10 of this embodiment, for example, in order to reduce fuel consumption while the vehicle is running, the engine 30 is automatically stopped while the vehicle is stopped, and the engine 30 is automatically restarted. A control called “and stop” is executed. FIG. 5 is a functional block diagram for explaining the main part of the control function of the electronic control unit 120 of FIG. 3. The main part of the control function related to the restart control of the engine 30 while the vehicle is stopped is shown in FIG. It is shown.

  Although not described in detail in the present embodiment, the S & S control unit 130 determines the automatic stop of the engine 30 of the vehicle that is stopped or coasting when a predetermined start condition is satisfied, and stops and automatically shifts the engine 30. In order to make the machine 12 neutral, the hydraulic friction engagement device such as the clutch C1 is released. Further, when the vehicle is stopped, for example, the brake pedal 68 is released from the brake switch 66, and the S & S control is returned based on a signal indicating the accelerator opening Acc from the accelerator opening sensor 52 to restart the engine 30. Determine whether or not to do so.

  The engine output control unit 122 opens and closes the electronic throttle valve so that a required output corresponding to the accelerator opening Acc from the accelerator opening sensor 52 is obtained based on the restart instruction of the engine 30 from the S & S control unit 130. A drive signal to the throttle actuator for controlling the engine, an injection signal for controlling the fuel injection amount injected from the fuel injection device, an ignition timing signal for controlling the ignition timing of the engine 30 by the igniter, and the like are controlled. An engine output control signal SE is output.

  The shift control unit 124 makes a shift determination based on the actual vehicle speed and the throttle opening from the shift map stored in advance, and the automatic transmission 12 establishes the gear stage for which the shift determination has been made. Any two of the clutches C1, C2 brakes B1, B2, B3 shown in FIG. Further, the shift control unit 124 controls the engagement state of the clutch C1 when the engine is restarted in accordance with a command from the S & S control unit 130.

  C1 slip determination unit 126 determines the slip start of clutch C1 based on the fact that turbine speed NT (rpm) after restart of engine 30 exceeds a preset slip start determination value SD1 (rpm). . Further, the C1 slip determination unit 126 determines the slip end of the clutch C1 when the turbine rotation speed NT becomes equal to or less than the preset slip end determination value SD2 (rpm) after the determination of the slip start of the clutch C1. The period from when the S & S control unit 130 gives an instruction to restart the engine 30 to the engine output control unit 122 until the C1 slip determination unit 126 determines the start of slipping of the clutch C1 is referred to as an initial explosion section. It is out.

  The clutch engagement control unit 128 receives the S & S return determination from the S & S control unit 130 or the restart determination of the engine 30, and exceeds the engagement pressure of the clutch C1 by a predetermined value that is relatively smaller than the engine torque at the first engine explosion. The hydraulic control command signal SP1 is output to the hydraulic control circuit 100 so that the pressure at which the standby torque capacity is obtained. Further, after the slip start determination by the C1 slip determination unit 126, the clutch engagement control unit 128 sets the rotation speed difference between the target turbine rotation speed NTt stored in advance and the actual turbine rotation speed NT to zero. The engagement pressure of the clutch C1 is feedback controlled. This target turbine rotational speed NTt is the same as the turbine rotational speed NT shown at t3 to t6 in FIG. 6, and is experimentally obtained as a desirable change in turbine rotational speed to suppress a shock when the clutch C1 is engaged. Time function. The clutch C1 is slipped so that the engine speed NE quickly reaches the complete explosion speed, and after reaching the complete explosion speed, the differential rotation of the clutch C1 is set to converge to zero.

  FIG. 6 is a time chart for explaining the operation of the engagement elements including the engine 30, the torque converter 32, and the clutch C1 when the engine 30 is automatically restarted and the clutch C1 is switched from the half-engaged state to the fully-engaged state. Is shown.

  In the stopped vehicle 10, when a predetermined S & S control return condition is satisfied, a command signal (engine restart instruction) is output from the S & S control unit 130, and the engine 30 is started by the engine output control unit 122. At the same time, an instruction signal is output from the S & S control unit 130 to the transmission control unit 124 and the clutch engagement control unit 128, and based on this instruction signal, the hydraulic control command signals SP1 and SP4 are transmitted from the transmission control unit 124 to the hydraulic circuit. 100 is output. For the purpose of improving the response speed of the clutch C1, a hydraulic pressure command value P2 set as a hydraulic pressure command value higher than the initial explosion hydraulic pressure command value P1 is output to the solenoid valve SL1 of the clutch C1, and the solenoid of the clutch B2 A control hydraulic pressure command value P3 for supplying the maximum engagement hydraulic pressure that is the line hydraulic pressure PL is output to the valve SL4. (At time t0 in FIG. 6). The hydraulic pressure command value P2 output to the solenoid valve SL1 of the clutch C1 is lowered to the initial explosion hydraulic pressure command value P1 after a preset time has elapsed. The initial explosion hydraulic pressure command value P1 is set in advance so that the clutch C1 does not slip at the first explosion of the engine 30, that is, the torque capacity of the clutch C1 exceeds the torque capacity of the clutch C1 by a predetermined value. (Time t1 in FIG. 6). The engine 30 starts a transition from the first explosion to the complete explosion (at time t2 in FIG. 6), and the engine rotational speed NE starts to gradually increase from the rotational speed r1 (rpm) at the first explosion. Further, the turbine rotational speed NT of the torque converter 32 similarly increases and reaches the slip start determination value SD1, that is, the rotational speed r4 (rpm). After the C1 slip determination unit 126 determines that the turbine rotational speed NT exceeds the slip start determination value SD1, the target turbine rotational speed NTt and the actual turbine rotational speed NT stored in advance in the clutch engagement control unit 128 are stored. Feedback control is started to make the difference in rotation speed zero. Therefore, thereafter, the engagement hydraulic pressure of the clutch C1 changes sequentially based on the command signal from the shift control unit 124 (at time t3 in FIG. 6). The target turbine speed NTt stored in advance is a time function that is experimentally obtained as a change in turbine speed that is desirable for suppressing a shock when the clutch C1 is engaged, and complete explosion of the engine 30 starts. Before that, the maximum value is set in advance so as to be the maximum turbine speed r5 (rpm) (t4 in FIG. 6), and is set in advance so as to maintain the maximum value until immediately after the start of the complete explosion (t5 in FIG. 6). ). After the complete explosion of the engine 30 is completed, the target turbine speed NTt is set to gradually decrease. When the clutch engagement control unit 128 determines that the turbine rotation speed NT is equal to or less than the slip end determination value SD2, that is, the rotation speed r3 (rpm), based on the command signal from the C1 slip determination unit 126, the shift control unit Due to the command signal output by the hydraulic control circuit 100 to 124, the hydraulic pressure command value to the solenoid valve SL1 of the clutch C1 becomes the same as the hydraulic pressure command value P3 given to the solenoid valve SL4 that controls the brake B2. Ascending, the slip state is terminated (t6 in FIG. 6).

  FIG. 6 shows the engine torque TE (Nm) and the output shaft torque TOUT (Nm) of the output shaft that corresponds to the output gear of FIG. 1 and is not shown. The engine torque TE (Nm) and the output shaft torque TOUT (Nm) are obtained experimentally, respectively, and the engine speed NE, turbine speed NT, C1 clutch oil pressure (MPa), B2 in FIG. The torque generated by the operation of the clutch hydraulic pressure (MPa) is shown. The solid lines of the engine torque TE (Nm) and the output shaft torque TOUT (Nm) indicate the torque generated when the above control is performed to reduce the engine restart shock in the stopped vehicle. On the other hand, the broken line of the output shaft torque (Nm) indicates the torque generated when the above control for reducing the shock is not performed, and the torque changes greatly in the vertical direction, and the torque generated on the output shaft. Change, or shock, is growing.

  FIG. 7 shows the main functions of the control function of the electronic control unit shown in FIGS. 3 and 5, that is, the engine and torque when the engagement device restarts the engine and switches from the half-engaged state to the full-engaged state. It is a flowchart explaining the principal part of the action | operation of a converter and an engagement element, and is repeatedly performed.

  In FIG. 7, first, in step S1 corresponding to the operation of the S & S control unit 130 (hereinafter, step is omitted), is the engine 30 restarted by determining whether or not the engine restart condition is satisfied, for example? It is determined whether or not. If this S1 determination is negative, this routine ends. If the determination is affirmative, for example, an engine restart instruction is sent to the engine output control unit 122 in S2 corresponding to the operation of the S & S control unit 130. Is output, and the restart of the vehicle 10 is started. In addition, an instruction signal is output from the S & S control unit 130 to the shift control unit 124 and the C1 slip determination unit 126, and in S3 corresponding to the operation of the shift control unit 124, the solenoid valve SL1 of the clutch C1 has an initial hydraulic pressure at the initial explosion. A hydraulic pressure command value P2 that is set higher than the command value P1 is output, and the hydraulic pressure command value P3 is supplied to the solenoid valves SL2 to SL5 of the other engagement elements C2, B1, and B3 including B2 in parallel therewith. The B2 control hydraulic pressure is supplied. The reason why the hydraulic pressure command value P2 to the solenoid valve SL1 of the clutch C1 is set higher than the hydraulic pressure command value P1 at the time of the initial explosion is to speed up the rise of the hydraulic pressure supplied to the clutch C1. Then, after a predetermined time, in S4 corresponding to the operation of the shift control unit 124, the initial explosion hydraulic pressure command value P1 is output to the solenoid valve SL1 of the clutch C1, and the C1 initial explosion hydraulic pressure is supplied. In S5 corresponding to the C1 slip determination unit 126, the C1 slip determination unit 126 determines whether or not the slip of the clutch C1 has exceeded a predetermined slip start determination value SD1, thereby determining the start of C1 clutch control. . If this S5 determination is negative, the supply of the C1 initial explosion hydraulic pressure and the determination of whether or not the slip start determination value SD1 of the clutch C1 has been exceeded are continued. If the S5 determination is affirmative, the shift control is performed. In S6 corresponding to the operation of the unit 124, the control for setting the difference in turbine speed between the map of the turbine speed stored in the C1 slip determination unit 126 in advance and the actual turbine speed NT to zero, that is, the C1 clutch control is started. Is done. After the complete explosion of the engine 30 is completed, the completion of C1 engagement is determined in S7 corresponding to the C1 slip determination unit 126. If this S7 determination is negative, the C1 clutch control is continued. If the S7 determination is affirmative, the hydraulic pressure command value P3 is output to the solenoid valve SL1 of the clutch C1, and the C1 control hydraulic pressure is output to the clutch C1. The slip state is supplied.

  If it does in this way, while the engine 30 transfers to a complete explosion from the first explosion, the clutch C1 of the automatic transmission 12 which engages with the engine 30 will be in a slip state. The clutch C1 slips during the transition from the first explosion in which the engine torque increases to the complete explosion, thereby suppressing the shock transmitted from the engine 30 that is generated by the increase in the engine torque.

  Further, after the C1 slip determination unit 126 determines that the turbine rotational speed NT of the torque converter 32 has exceeded the slip start determination value SD1, the C1 slip determination unit 126 approaches the turbine rotational speed map stored in advance in the C1 slip determination unit 126. Thus, the hydraulic pressure to the clutch C1 is controlled. This turbine speed map stored in advance is a map that is experimentally determined as a change in turbine speed that is desirable for suppressing shock when the clutch C1 is engaged, and is applied to the clutch C1 so as to approach this map. Is controlled by feedback. Thereby, the shock can be further effectively suppressed.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this invention is applied also in another aspect.

  For example, in the above-described embodiment, in the initial explosion section from the restart instruction of the engine 30 to the start of the C1 slip, the clutch is set so that the standby torque capacity at the initial explosion hydraulic pressure exceeds the engine torque at the initial explosion by a predetermined value. The engagement pressure of C1 was increased. However, this condition takes into account variations in engine characteristics. If the slip of the clutch C1 does not exceed a predetermined slip start determination value during the initial explosion period, the engagement pressure of the clutch C1 is set to the initial explosion. It can be equal to the engine torque at the time, or less than the engine torque at the first explosion.

  Further, the hydraulic pressure command value P2 output to the solenoid valve SL1 of the clutch C1 when the engine 30 is restarted is set to be higher than the hydraulic pressure command value P1 at the time of the initial explosion to improve the rising of the hydraulic pressure, but is supplied to the clutch C1. As long as the rising speed of the hydraulic pressure is not a problem, it is not particularly necessary to output the hydraulic pressure command value that is set higher than the initial explosion hydraulic pressure command value P1. The switching from the hydraulic pressure command value P2 to the initial explosion hydraulic pressure command value P2 is performed after the elapse of a preset time. However, for example, the switching may be determined by directly measuring the hydraulic pressure.

  Further, in the initial explosion section from the restart instruction of the engine 30 to the start of the C1 slip, the engagement hydraulic pressure of the clutch C1 is controlled so as to approach the preset turbine rotation speed. The generated torque may be measured, and the hydraulic pressure applied to the clutch C1 may be controlled so that the torque approaches a time change (map) of torque stored in advance.

  In addition, although not illustrated one by one, the present invention can be implemented even if various changes are made without departing from the spirit of the present invention.

10: Vehicle 12: Automatic transmission 30 for vehicle: Engine 100: Hydraulic control circuit (control device)
C1, C2: Clutch (engagement element)
B1, B2, B3: Brake (engaging element)

Claims (1)

In a vehicle equipped with an engine and an automatic transmission, the engine is automatically stopped when a predetermined condition is satisfied, and the engaging element of the automatic transmission is released to bring the automatic transmission into a neutral state. A control device for an automatic transmission for a vehicle that restarts the engine and engages the engagement element when a start condition is satisfied,
When the engine is restarted, the engagement element of the automatic transmission for vehicle is engaged so that a standby torque capacity that exceeds the engine torque at the time of the first explosion by a predetermined value in the first explosion section of the engine, The engagement pressure is increased while slipping of the engagement element is started after the slip of the engagement element is started, the engagement pressure is further increased after completion of the complete explosion of the engine, and the slip state is terminated. A control device for an automatic transmission for vehicles.

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