JP2012237402A - Control device of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a vehicle that reliably avoids delay of departure of a vehicle by calculating idle reduction duration accurately, when idle reduction is carried out in the vehicle without using an electric hydraulic pump.SOLUTION: The device detects (S10, S12, and S14) a change of hydraulic pressure supplied from a hydraulic pump driven by an engine when idling of the engine is stopped; estimates lack-of-hydraulic-pressure time on the basis of the detected change of the hydraulic pressure, in particular, from the change of hydraulic pressure to calculate (S14) the idle reduction duration by, e.g., searching predetermined characteristics from the estimated value; and restarts the engine after the calculated idle reduction duration passes.

Description

  The present invention relates to a vehicle control device, and more specifically to a vehicle control device in which an engine is idle-stopped when waiting for a signal.

  In vehicles where the engine is idle-stopped when waiting for a signal, etc., it is usual to provide an electric hydraulic pump separately from the hydraulic pump driven by the engine, but idle-stopping is also performed in vehicles that do not use an electric hydraulic pump. Examples thereof include the technique described in Patent Document 1.

  In vehicles that do not use an electric hydraulic pump, the hydraulic pump is also stopped in the idle stop state, and no hydraulic pressure is supplied to the automatic transmission. Therefore, when the engine is restarted after the idle stop is completed, the shift operation of the automatic transmission is delayed. As a result, there is an inconvenience that the start of the vehicle is delayed.

  Therefore, in the technique described in Patent Document 1, the engine is restarted when the elapsed time from the idle stop reaches a predetermined time, and the predetermined time is increased or decreased by the oil temperature. That is, it is configured to estimate the hydraulic pressure release time and determine a predetermined time (idle stop duration).

JP 2010-230132 A

  The technique described in Patent Document 1 is configured as described above to attempt to eliminate the delay in starting the vehicle after the end of the idle stop. However, in actuality, the oil temperature is used to accurately calculate the idle stop duration. Have difficulty.

  That is, FIG. 9 is measurement data showing the relationship of the oil temperature with respect to the hydraulic pressure release time in the automatic transmissions a, b, c, d of the same model. As shown in the figure, there is a correlation between the oil pressure release time and the oil temperature, but the influence of product (manufacturing) variation on the same oil temperature is large. Accordingly, it is difficult to accurately calculate the idle stop duration using the oil temperature, and it is difficult to reliably avoid the delay in starting the vehicle.

  When the automatic transmission is a CVT (continuously variable transmission), the circumferential surface of the movable piston wall forming the piston chamber of the movable pulley half of the pulley (friction engagement element) has a C-shape when viewed from the side. An annular seal ring that is meshed with the ring is fitted, and the space between the circumferential surface of the piston chamber is liquid-tightly sealed to prevent hydraulic pressure (hydraulic oil) leakage. The hydraulic fluid leaks depending on its own weight when it moves in accordance with the rotation of the half body and is located below and above in the direction of gravity. The position in the direction of gravity is not limited, but the hydraulic pressure may leak from the hydraulic control valve of the hydraulic pressure supply mechanism.

  Therefore, the object of the present invention is to solve the above-mentioned inconveniences, and when idle-stopping in a vehicle that does not use an electric hydraulic pump, the idle-stop duration time is accurately calculated to reliably avoid a delay in starting the vehicle. It is in providing the control apparatus of a vehicle.

  In order to achieve the above object, according to a first aspect of the present invention, an engine, a hydraulic pump driven by the engine, and a hydraulic pressure supplied from the hydraulic pump are operated to change the output of the engine. Supplyed from the hydraulic pump when the engine is idle-stopped in a vehicle having an automatic transmission that transmits to the drive wheels and idle stop means that idle-stops the engine when a predetermined condition is satisfied Oil pressure change detecting means for detecting a change in oil pressure, idle stop duration calculating means for calculating an idle stop duration for which the idle stop should be continued based on the detected oil pressure change, and the calculated idle stop Engine restarting means for restarting the engine when the duration has elapsed. .

  In the vehicle control device according to claim 2, the oil pressure change detecting unit measures an elapsed time from when the engine is idle-stopped until the oil pressure is lowered to a predetermined oil pressure, thereby changing the oil pressure. It was comprised so that it might detect.

  In the vehicle control device according to claim 3, the oil pressure change detecting unit measures an elapsed time until the oil pressure decreases from a predetermined oil pressure to a predetermined oil pressure when the engine is idle-stopped. The hydraulic pressure change is detected.

  In the vehicle control device according to a fourth aspect, the hydraulic pressure change detecting means is configured to detect a change in hydraulic pressure supplied from the hydraulic pump to the friction engagement element of the automatic transmission.

  The vehicle control apparatus according to claim 5 is configured such that the predetermined hydraulic pressure is set to a minute value near zero.

  In the vehicle control device according to claim 1, when the engine is idle-stopped, a change in hydraulic pressure supplied from a hydraulic pump driven by the engine is detected, and an idle is based on the detected change in hydraulic pressure. The idle stop duration time for which the stop should be continued is calculated, and the engine is restarted when the calculated idle stop duration time has elapsed. Since the configuration is such that the idle stop duration is calculated by estimating the amount of change in hydraulic pressure and, for example, searching for a preset characteristic from the estimated value, use an oil temperature that has a large influence on the object variation of the automatic transmission. Therefore, the idle stop duration can be accurately calculated.

  When the automatic transmission is a CVT (continuously variable transmission), the seal ring fitted to the movable piston wall forming the piston chamber of the movable pulley half is positioned downward in the direction of gravity when idling is stopped. However, as described above, it is not affected by the position of the seal ring by actually detecting the change in the hydraulic pressure at the time of idling stop, as described above. It is possible to calculate the idle stop duration accurately. Therefore, it is possible to reliably avoid a delay in starting the vehicle after the end of the idle stop.

  The vehicle control apparatus according to claim 2 is configured to detect a change in hydraulic pressure by measuring an elapsed time from when the engine is idle-stopped until the hydraulic pressure drops to a predetermined hydraulic pressure. In addition to the effect, it is possible to accurately detect the hydraulic pressure release time.

  The vehicle control device according to claim 3 is configured to detect a change in hydraulic pressure by measuring an elapsed time until the hydraulic pressure drops from a predetermined hydraulic pressure to a predetermined hydraulic pressure when the engine is idle-stopped. Therefore, in addition to the above-described effects, it is possible to accurately detect the hydraulic pressure drop change amount.

  The vehicle control apparatus according to claim 4 is configured to detect a change in the hydraulic pressure supplied from the hydraulic pump to the friction engagement element of the automatic transmission. By detecting the change in the hydraulic pressure supplied to the frictional engagement element that affects the delay, the hydraulic pressure loss time or the hydraulic pressure loss change amount can be detected with high accuracy.

  The vehicle control apparatus according to claim 5 is configured such that the predetermined hydraulic pressure is set to a minute value near zero, so that in addition to the above-described effects, if the predetermined hydraulic pressure is zero, The detection value is the same whether or not there is air in the air, but by setting it to a very small pressure, it is possible to eliminate the case where there is air in the oil pressure at the detection location, so that the oil pressure release time can be detected more accurately. it can.

1 is a schematic diagram showing an overall control apparatus for a vehicle according to a first embodiment of the present invention. FIG. 2 is a hydraulic circuit diagram of the hydraulic pressure supply mechanism shown in FIG. 1. It is a flowchart which shows operation | movement of the apparatus shown in FIG. It is experimental data which shows the change of the oil pressure after an engine is stopped. 3 is an explanatory graph showing characteristics of IS duration with respect to hydraulic pressure release time used in the processing of the flow chart of FIG. It is a flowchart which shows operation | movement of the control apparatus of the vehicle which concerns on 2nd Example of this invention. FIG. 5 is experimental data similar to FIG. 4 showing a change in hydraulic pressure after the engine is stopped. 6 is an explanatory graph showing characteristics of IS duration with respect to a hydraulic pressure drop change amount used in the processing of the flow chart. It is measurement data which shows the relationship of the oil temperature with respect to the hydraulic pressure release time in the automatic transmission of the same model.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a mode for carrying out a vehicle control apparatus according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram showing the overall control apparatus for a vehicle according to the first embodiment of the present invention.

  In FIG. 1, reference numeral 10 denotes an engine (an internal combustion engine (prime mover)). The engine 10 is mounted on a vehicle (partially indicated by drive wheels 12 and the like) 14.

  A throttle valve (not shown) arranged in the intake system of the engine 10 is mechanically disconnected from an accelerator pedal (not shown) arranged in the vehicle driver's seat, and is a DBW (actuator) such as an electric motor. Drive By Wire) mechanism 16 is connected and driven.

  The intake air metered by the throttle valve flows through an intake manifold (not shown), mixes with fuel injected from the injector 20 near the intake port of each cylinder to form an air-fuel mixture, and an intake valve (not shown) When the valve is opened, it flows into the combustion chamber (not shown) of the cylinder. In the combustion chamber, the air-fuel mixture is ignited and combusted, and after driving the piston and rotating the crankshaft 22, the air-fuel mixture is exhausted and discharged outside the engine 10.

  The rotation of the crankshaft 22 of the engine 10 is input to a continuously variable transmission (hereinafter referred to as “CVT”) 26 via a torque converter 24. That is, the crankshaft 22 is connected to the pump / impeller 24a of the torque converter 24, while the turbine runner 24b disposed opposite thereto and receiving fluid (hydraulic oil) is connected to the main shaft (input shaft) MS.

  The CVT 26 includes a drive pulley (friction engagement element) 26a disposed on the main shaft MS, a driven pulley (friction engagement element) 26b disposed on a counter shaft (output shaft) CS parallel to the main shaft MS, and a gap therebetween. It consists of a metal belt 26c to be wound around.

  The drive pulley 26a is fixed to the main shaft MS so that it cannot rotate relative to the main shaft MS and cannot move in the axial direction. The drive pulley 26a cannot move relative to the main shaft MS and can move relative to the fixed pulley half 26a1 in the axial direction. And a movable pulley half 26a2.

  Similarly, the driven pulley 26b is fixed relative to the countershaft CS in the axial direction with respect to the stationary pulley half 26b1 which is not rotatable relative to the countershaft CS and is not movable in the axial direction. The movable pulley half 26b2 is movable.

  The CVT 26 includes a forward / reverse switching device 30. The forward / reverse switching device 30 includes a forward clutch (friction engagement element) 30a, a reverse brake clutch (friction engagement element) 30b, and a planetary gear mechanism 30c disposed therebetween. The CVT 26 is connected to the engine 10 via the forward clutch 30a.

  In the planetary gear mechanism 30c, the sun gear 30c1 is fixed to the main shaft MS, and the ring gear 30c2 is fixed to the fixed pulley half 26a1 of the drive pulley 26a via the forward clutch 30a.

  A pinion 30c3 is disposed between the sun gear 30c1 and the ring gear 30c2. Pinion 30c3 is coupled to sun gear 30c1 by carrier 30c4. When the reverse brake clutch 30b is operated, the carrier 30c4 is fixed (locked) thereby.

  The rotation of the counter shaft CS is transmitted to the secondary shaft (intermediate shaft) SS via the reduction gears 34 and 36, and the rotation of the secondary shaft SS is transmitted to the left and right drive wheels (only the right side is shown) 12 via the gear 40 and the differential D. To be told. A disc brake 42 is disposed in the vicinity of the drive wheel 12 (and a driven wheel (not shown)).

  Switching between the forward clutch 30a and the reverse brake clutch 30b is performed by the driver operating a shift lever 44 provided at a vehicle driver's seat, for example, having positions P, R, N, D, S, and L. When any position of the shift lever 44 is selected by the driver, the selection operation is transmitted to the manual valve of the hydraulic pressure supply mechanism 46 such as the CVT 26.

  For example, when the D, S, and L positions are selected, the spool of the manual valve moves accordingly, and hydraulic oil (hydraulic pressure) is discharged from the piston chamber of the reverse brake clutch 30b, while the hydraulic oil (hydraulic pressure) is discharged to the piston chamber of the forward clutch 30a. Hydraulic pressure is supplied and the forward clutch 30a is engaged.

  When the forward clutch 30a is engaged, all gears rotate together with the main shaft MS, and the drive pulley 26a is driven in the same direction (forward direction) as the main shaft MS.

  On the other hand, when the R position is selected, hydraulic oil is discharged from the piston chamber of the forward clutch 30a, while hydraulic pressure is supplied to the piston chamber of the reverse brake clutch 30b, and the reverse brake clutch 30b is operated. As a result, the carrier 30c4 is fixed, the ring gear 30c2 is driven in the opposite direction to the sun gear 30c1, and the drive pulley 26a is driven in the opposite direction (reverse direction) to the main shaft MS.

  When the P or N position is selected, hydraulic oil is discharged from both piston chambers, the forward clutch 30a and the reverse brake clutch 30b are both released, and power transmission via the forward / reverse switching device 30 is cut off. The power transmission between the engine 10 and the drive pulley 26a of the CVT 26 is cut off.

  FIG. 2 is a hydraulic circuit diagram of the hydraulic pressure supply mechanism 46.

  As illustrated, the hydraulic pressure supply mechanism 46 is provided with a hydraulic pump 46a. The hydraulic pump 46a is a gear pump, is driven by the engine 10, pumps up hydraulic oil stored in the reservoir 46b, and pumps it to a PH control valve (PH REG VLV) 46c.

  On the other hand, the output (PH pressure (line pressure)) of the PH control valve 46c is supplied from the oil passage 46d via the first and second regulator valves (DR REG VLV, DN REG VLV) 46e, 46f. Are connected to the piston chamber (DR) 26a21 of the movable pulley half 26a2 and the piston chamber (DN) 26b21 of the movable pulley half 26b2 of the driven pulley 26b, and on the other hand, the CR valve (CR VLV) via the oil passage 46g. 46h.

  The CR valve 46h reduces the PH pressure to generate a CR pressure (control pressure), and the first, second and third (electromagnetic) linear solenoid valves 46j, 46k, 46l (LS-DR, LS) from the oil passage 46i. -DN, LS-CPC). The first and second linear solenoid valves 46j and 46k act on the first and second regulator valves 46e and 46f with the output pressure determined according to the excitation of the solenoids, and thus the PH pressure sent from the oil passage 46d. Is supplied to the piston chambers 26a21 and 26b21 of the movable pulley halves 26a2 and 26b2, and a pulley side pressure is generated accordingly.

  Therefore, in the configuration shown in FIG. 1, the pulley side pressure that moves the movable pulley halves 26a2 and 26b2 in the axial direction is generated, the pulley widths of the drive pulley 26a and the driven pulley 26b change, and the winding radius of the belt 26c changes. Changes. Thus, by adjusting the side pressure of the pulley, the transmission gear ratio for transmitting the output of the engine 10 to the drive wheels 12 can be changed steplessly.

  As described above, the circumferential surface of the movable piston wall forming the piston chambers 26a21 and 26b21 of the movable pulley halves 26a2 and 26b2 is engaged with a C-shaped ring in a side view to form an annular seal ring ( (Not shown) is fitted, and the space between the circumferential surface of the piston chamber is liquid-tightly sealed to prevent leakage of hydraulic pressure (hydraulic oil). Since the seal ring is described in, for example, Japanese Patent Laid-Open No. 2007-78041, detailed description thereof is omitted.

  Returning to the description of FIG. 2, the output (CR pressure) of the CR valve 46h is also connected to the CR shift valve (CR SFT VLV) 46n via the oil passage 46m, from which the manual valve (MAN VLV. Reference numeral 46o). Are connected to the piston chamber (FWD) 30a1 of the forward clutch 30a of the forward / reverse switching device 30 and the piston chamber (RVS) 30b1 of the reverse brake clutch 30b.

  As described with reference to FIG. 1, the manual valve 46o outputs the output of the CR shift valve 46n according to the position of the shift lever 44 operated (selected) by the driver, and the piston chamber 30a1 of the forward clutch 30a and the reverse brake clutch 30b. , 30b1.

  The output of the PH control valve 46c is sent to the TC regulator valve (TC REG VLV) 46q via the oil passage 46p, and the output of the TC regulator valve 46q is LC shifted via the LC control valve (LC CTL VLV) 46r. Connected to valve (LC SFT VLV) 46s.

  The output of the LC shift valve 46s is connected to the piston chamber 24c1 of the lock-up clutch (friction engagement element) 24c of the torque converter 24 on the one hand and to the chamber 24c2 on the other side on the other hand.

  When hydraulic oil is supplied to the piston chamber 24c1 via the LC shift valve 46s, the lock-up clutch 24c is engaged (turned on) when supplied from the back chamber 24c2, and is supplied to the back chamber 24c2. On the other hand, when discharged from the piston chamber 24c1, it is released (off). The slip amount of the lockup clutch 24c is determined by the amount of hydraulic oil supplied to the piston chamber 24c1 and the rear chamber 24c2.

  The output of the CR valve 46h is connected to an LC control valve 46r and an LC shift valve 46s through an oil passage 46t, and a fourth linear solenoid valve (LS-LC) 46u is inserted in the oil passage 46t. The slip amount of the lock-up clutch 24c is adjusted (controlled) by exciting / de-energizing the solenoid of the fourth linear solenoid valve 46u.

  Returning to the description of FIG. 1, a crank angle sensor 50 is provided at an appropriate position such as near the cam shaft (not shown) of the engine 10 and outputs a signal indicating the engine speed NE for each predetermined crank angle position of the piston. To do. In the intake system, an absolute pressure sensor 52 is provided at an appropriate position downstream of the throttle valve, and outputs a signal proportional to the intake pipe absolute pressure (engine load) PBA.

  The actuator of the DBW mechanism 16 is provided with a throttle opening sensor 54, and outputs a signal proportional to the throttle valve opening TH through the rotation amount of the actuator.

  An accelerator opening sensor 56a is provided in the vicinity of the accelerator pedal 56 to output a signal proportional to the accelerator opening AP corresponding to the driver's accelerator pedal operation amount, and a brake switch 58a in the vicinity of the brake pedal 58. Is provided to output an ON signal in response to the driver's operation of the brake pedal 58.

  Further, a water temperature sensor 60 is provided in the vicinity of a cooling water passage (not shown) of the engine 10 to generate an output corresponding to the engine cooling water temperature TW, in other words, the temperature of the engine 10.

  The output of the crank angle sensor 50 and the like described above is sent to the engine controller 66. The engine controller 66 includes a microcomputer, determines the target throttle opening based on the sensor outputs, controls the operation of the DBW mechanism 16, and determines the fuel injection amount to drive the injector 20.

  The main shaft MS is provided with an NT sensor (rotational speed sensor) 70, which determines the rotational speed of the turbine runner 24b, specifically the rotational speed of the main shaft MS, more specifically the input shaft rotational speed of the forward clutch 30a. The pulse signal shown is output.

  An NDR sensor (rotational speed sensor) 72 is provided at an appropriate position near the drive pulley 26a of the CVT 26, and outputs a pulse signal corresponding to the rotational speed of the drive pulley 26a, in other words, the output shaft rotational speed of the forward clutch 30a. In addition, an NDN sensor (rotational speed sensor) 74 is provided at an appropriate position near the driven pulley 26b, and outputs a pulse signal indicating the rotational speed of the driven pulley 26b.

  A VEL sensor (rotational speed sensor) 76 is provided in the vicinity of the gear 36 of the secondary shaft SS and outputs a pulse signal indicating the rotational speed of the output shaft of the CVT 26 or the vehicle speed VEL through the rotational speed of the gear 36. A shift lever position sensor 80 is provided in the vicinity of the shift lever 44 described above, and outputs a POS signal corresponding to a position such as R, N, or D selected by the driver.

  A wheel speed sensor 82 is provided at an appropriate position of each of the four wheels (tires) including the driving wheel 12 and the driven wheel, and outputs a signal proportional to the wheel speed indicating the rotational speed of the wheel.

  Further, as shown in FIG. 2, a hydraulic pressure (P) sensor 84 is disposed in an oil passage leading to the driven pulley 26b of the CVT 26 in the hydraulic pressure supply mechanism 46, and is supplied to the piston chamber 26b21 of the movable pulley half 26b2 of the driven pulley 26b. A signal corresponding to the hydraulic pressure Pdnpully is output, and an oil temperature sensor 86 is arranged in the reservoir 46b to output a signal corresponding to the oil temperature (temperature TATF of the hydraulic oil ATF).

  The output of the NT sensor 70 and the like described above is sent to the shift controller 90 including the outputs of other sensors (not shown). The shift controller 90 also includes a microcomputer and is configured to be able to communicate with the engine controller 66.

  Based on the detected values, the shift controller 90 excites and de-energizes electromagnetic solenoids such as the first and fourth on / off solenoids 46u of the hydraulic pressure supply mechanism 46 to operate the forward / reverse switching device 30, the CVT 26, and the torque converter 24. To control.

  In addition to the DBW mechanism 16 and fuel injection control, the engine controller 66 performs idle stop control of the vehicle 14.

  3 is an idle stop control of the engine controller 66. More specifically, FIG. 3 (a) is a calculation of the idle stop duration, and FIG. 3 (b) is a flowchart showing a restart request process after the idle stop. It is. The illustrated program is executed every predetermined time, for example, every 10 msec.

  In the following, it is determined whether or not the vehicle 14 is idling stopped in S10.

  That is, when the vehicle 14 waits for a signal or the like, the engine controller 66 operates (depresses) the brake pedal 58 of the vehicle 14 by a driver while the vehicle speed is zero and the accelerator pedal 56 is operated. If the condition such as the ratio of the CVT 26 is not satisfied is satisfied, and if affirmative, the engine 10 is idle-stopped. In S10, it is determined whether or not the engine is in such an idle-stop state. To do.

  When the result in S10 is negative, the subsequent processing is skipped. On the other hand, when the result is affirmative and it is determined that the engine 10 is idle stopped, the process proceeds to S12, and an IS (idle stop) continuation timer (described later) is set. Determine whether or not.

  When the result in S12 is affirmative, the subsequent processing is skipped, while when the result is negative, the process proceeds to S14, where a change in hydraulic pressure is detected and the IS duration time is searched.

  Specifically, based on the output of the hydraulic sensor 84, the hydraulic pressure supplied to the friction engagement element (detected by the hydraulic sensor 84) after the engine 10 is idle-stopped using an appropriate timer counter, that is, A change in hydraulic pressure is detected by measuring an elapsed time (sec) tx until the hydraulic pressure Pdnpully supplied to the piston chamber 26b21 of the driven pulley 26b of the CVT 26 decreases to a predetermined hydraulic pressure Pref, and the idle stop is continued based on the change. Calculate the power IS duration.

  FIG. 4 is experimental data showing a change in the hydraulic pressure Pdnpully (and the hydraulic pressure PFWDCL supplied to the piston chamber 30a1 of the forward clutch 30a) after the engine 10 is stopped.

  As shown in the figure, the hydraulic pressure suddenly decreases as the engine speed NE suddenly drops (stop of the engine 10), and the hydraulic pressure from the time ts when the engine 10 is stopped, for example, the hydraulic pressure Pdnpully further decreases to a predetermined hydraulic pressure Pref (zero). The value drops below a very small value (for example, a hydraulic pressure set to 0.05 MPa).

  In the illustrated data, at time t1, the meshing portion of the seal ring fitted to the circumferential surface of the movable piston wall forming the piston chamber 26a21 or 26b21 of the movable pulley half of the drive pulley 26a and the driven pulley 26b is gravity. The time t2 shows the case where it is located upward on the contrary, when it is located below in the direction. When the meshing portion is positioned below, it is likely to leak (easily come off) due to its own weight of hydraulic oil, compared to when it is positioned above.

  In particular, when idling is stopped, the CVT 26 is supplied by expanding the piston chamber 26b21 of the movable pulley half of the driven pulley 26b so that the belt winding diameter of the driven pulley 26b is increased and the transmission gear ratio becomes low. Since the hydraulic pressure is increased and the amount of hydraulic oil is larger than that on the drive pulley 26a side, the influence of the position of the meshing portion of the seal ring becomes significant. In addition, the hydraulic pressure may leak from the PH control valve 46c of the hydraulic pressure supply mechanism 46.

  The illustrated data is experimental data for the same product and the same CVT 26, and is the first and second test data performed under the same conditions. Since the movable pulley half 26b2 (or 26a2) rotates in accordance with the countershaft CS (or main shaft MS), the position of the meshing portion of the seal ring also moves in accordance with traveling.

  FIG. 5 is an explanatory graph showing the characteristics of the IS duration with respect to the hydraulic pressure release time tx. As the hydraulic pressure release time tx is longer, it means that the hydraulic pressure is less likely to be released (difficult to leak) from the forward clutch 30a (or the driven pulley 26b of the CVT 26). Therefore, as shown in FIG. It is obtained and set in advance by experiments so as to increase.

  In the process of S14, at the same time, the IS duration time is calculated by searching the preset characteristics shown in FIG. 5 with the measured hydraulic pressure release time tx.

  Returning to the description of the flow chart of FIG. 3A, the process proceeds to S16, and the IS continuation timer is set. That is, the calculated IS duration time is set in a timer (down counter) and time measurement is started.

  FIG. 3B is a flowchart showing processing performed in parallel with FIG.

  Explained below, in S100, it is determined whether BrkOFF, that is, whether the brake pedal 58 has been released by the driver from the output of the brake switch 58a. If the determination is affirmative, the process proceeds to S102 and the engine 10 is restarted.

  On the other hand, when the result in S100 is negative, the process proceeds to S104, and it is determined whether or not the accelerator pedal 56 is stepped on by the driver from APON, that is, the output of the accelerator opening sensor 56a.

  On the other hand, when the result in S104 is negative, the program proceeds to S106, in which it is determined whether or not the value of the above-mentioned IS continuation timer has reached zero, in other words, whether or not the calculated IS continuation time has passed. If YES, go to S102.

  That is, when it is determined that the calculated IS continuation time has elapsed, the engine 10 is restarted. On the other hand, when the result in S106 is NO, the program proceeds to S108, and IS continuation, that is, idle stop is continued.

  In the vehicle control apparatus according to this embodiment, when the engine 10 is idle-stopped, a change in hydraulic pressure supplied from the hydraulic pump 46a driven by the engine 10 is detected, and the detected change in hydraulic pressure is detected. The system is configured to calculate the IS duration time for which the idle stop (IS) should be continued based on the above, and to restart the engine 10 when the calculated IS duration time has elapsed, in other words, the hydraulic pressure regardless of the oil temperature. More specifically, the elapsed time from when the engine 10 is idle stopped until the hydraulic pressure drops to a predetermined hydraulic pressure is measured to estimate the hydraulic pressure release time and calculate the IS duration time.

  That is, the movable piston wall that forms the piston chamber of the movable pulley halves 26a2 and 26b2 by detecting the change in hydraulic pressure at the time of idling stop without using the oil temperature that is greatly affected by the variation of the CVT 26 Therefore, the IS continuation time can be accurately calculated, and the delay in starting the vehicle 14 after the end of the idle stop can be reliably avoided.

  FIG. 6 is a flowchart showing an idle stop duration calculation process similar to that in FIG. 3A, showing the operation of the vehicle control apparatus according to the second embodiment of the present invention. The illustrated program is also executed every predetermined time, for example, every 10 msec.

  In the following description, the same determination as in the first embodiment is made in S10 and S12. When the result in S12 is negative, the program proceeds to S14a, where a change in hydraulic pressure is detected and the IS duration time is searched.

  Specifically, when the engine 10 is idlingly stopped, an elapsed time (sec) until the hydraulic pressure sensor hydraulic pressure decreases from the predetermined hydraulic pressure Ps to the predetermined hydraulic pressure Pref using a timer counter based on the output of the hydraulic pressure sensor 84. A change in hydraulic pressure is detected by measuring ty.

  More specifically, when the engine 10 is idle-stopped, the hydraulic pressure supplied to the friction engagement element (detected by the hydraulic sensor 84), that is, the hydraulic pressure supplied to the piston chamber 26b21 of the driven pulley 26b of the CVT 26. A change in oil pressure is detected by measuring an elapsed time ty until Pdnpully decreases from a predetermined oil pressure Ps to a predetermined oil pressure Pref, and an IS duration is calculated based on the change.

  FIG. 7 is experimental data showing changes in the hydraulic pressure Pdnpully and the like after the engine 10 is stopped.

  Since the hydraulic pressure rapidly decreases as the engine speed NE rapidly decreases, for example, the hydraulic pressure Pdnpully decreases from the predetermined hydraulic pressure Ps to the predetermined hydraulic pressure Pref. Time t3 is when the meshing portion of the seal ring fitted on the circumferential surface of the movable piston wall of the piston chamber 26a21 or 26b21 of the pulley half is located below in the direction of gravity, and time t4 is when it is located above. Show.

  Note that when the engine 10 is idle-stopped, the hydraulic pressure suddenly decreases with a sudden drop in the engine speed NE, and then stabilizes to a low value and then gradually decreases. Means a stable low value.

  FIG. 8 is an explanatory graph showing characteristics of IS duration time with respect to hydraulic pressure release time ty.

  As the hydraulic pressure release time ty is longer, it means that the hydraulic pressure is less likely to be released from the forward clutch 30a (or the driven pulley 26b of the CVT 26) (not easily leaked). It is obtained and set in advance by experiments so as to increase.

  In the process of S14 in the flow chart of FIG. 6, the IS duration time is calculated by searching the preset characteristics shown in FIG. 8 with the hydraulic pressure release time ty measured at the same time.

  Next, as in the first embodiment, the process proceeds to S16, where the IS continuation timer is set and the program is terminated. It is not different from the first embodiment that the process shown in FIG.

  Even in the vehicle control apparatus according to the second embodiment, when the engine 10 is idle-stopped, a change in the hydraulic pressure supplied from the hydraulic pump 46a driven by the engine 10 is detected, and the detected change in the hydraulic pressure is detected. Is configured to restart the engine 10 when the calculated IS duration has elapsed, in other words, the change in hydraulic pressure regardless of the oil temperature, more specifically, When the engine 10 is idle stopped, the elapsed time ty until the hydraulic pressure drops from the predetermined hydraulic pressure Ps to the predetermined hydraulic pressure Pref is measured to estimate the hydraulic pressure release time and calculate the IS duration time. As in the first embodiment, the oil temperature is not greatly affected by the variation of the CVT 26 and is not affected by the position of the seal ring. Time can accurately calculate the the delay of the start of the idle stop after the end of the vehicle 14 can be reliably avoided.

  As described above, in the first and second embodiments, the engine 10, the hydraulic pump 46a driven by the engine, and the hydraulic pressure supplied from the hydraulic pump operate to shift the output of the engine. The vehicle 10 includes an automatic transmission (CVT) 26 that transmits to the drive wheels 12 and idle stop means (engine controller 66) that idles the engine 10 when a predetermined condition is satisfied. When the engine is idle stopped, hydraulic pressure change detecting means (S10, S12, S14, S14a) for detecting a change in the hydraulic pressure supplied from the hydraulic pump 46a, and the idle stop ( The idle stop duration calculation means (S14) for calculating the idle stop duration for which IS is to be continued S14a) and engine restarting means (S100 to S108) for restarting the engine 10 when the calculated idle stop duration has elapsed, in other words, the hydraulic pressure regardless of the oil temperature. The configuration is such that the idle pressure continuation time is calculated by measuring the hydraulic pressure release time from the change and searching for, for example, a preset characteristic from the estimated value, so that there is a large influence of object variation of the CVT (automatic transmission) 26. Since the oil temperature is not used, the idle stop duration can be accurately calculated, and because the oil temperature is not used, the idle stop duration can be accurately calculated.

  In addition, when the seal ring fitted to the movable piston wall forming the piston chamber 26a21 or 26b21 of the movable pulley half is positioned at a lower position in the gravitational direction at the time of idle stop, and when the seal ring is positioned at an upper position, Although the leaks are different, as described above, the actual change in the hydraulic pressure at the time of idling stop is not affected by the position of the seal ring, so that the idling stop duration time can also be accurately calculated. Therefore, it is possible to reliably avoid the delay in starting the vehicle 14 after the end of the idle stop.

  Further, the oil pressure change detecting means is configured to detect a change in the oil pressure by measuring an elapsed time tx from when the engine 10 is idle-stopped until the oil pressure drops to a predetermined oil pressure Pref (S14). Therefore, in addition to the above-described effects, the hydraulic pressure release time can be detected with high accuracy.

  Further, the oil pressure change detecting means detects the change in the oil pressure by measuring an elapsed time ty until the oil pressure decreases from the predetermined oil pressure Ps to the predetermined oil pressure Pref when the engine 10 is idle-stopped. Since it comprised, in addition to the above-described effect, it is possible to accurately detect the amount of change in hydraulic pressure loss.

  The hydraulic pressure change detecting means is configured to detect a change in the hydraulic pressure Pdnpully supplied to the friction engagement element (driven pulley) 26 of the automatic transmission (CVT) 26 from the hydraulic pump 46a. In addition to the effect, by detecting the change in the hydraulic pressure supplied to the frictional engagement element that affects the start delay of the vehicle 14, the hydraulic pressure loss time or the hydraulic pressure loss change amount can be detected with high accuracy.

  Further, since the predetermined hydraulic pressure Pref is set to a minute value (for example, 0.05 MPa) near the hydraulic pressure zero, in addition to the above effect, if the predetermined hydraulic pressure Pref is set to zero, air is detected in the detected hydraulic pressure. The detected value is the same in both cases, but by setting it to a very small pressure, it is possible to eliminate the case where there is air in the oil pressure at the detection location, and therefore it is possible to detect the hydraulic pressure release time with higher accuracy.

  In the above description, the hydraulic pressure release time is measured and the idle stop duration time is calculated from the estimated value. However, the oil temperature may be taken into consideration in addition thereto.

  Further, the hydraulic pressure Pdnpully supplied to the piston chamber 26b21 of the driven pulley 26b of the CVT 26 of the forward / reverse switching device 30 is detected as the hydraulic pressure supplied to the friction engagement element, but as shown by an imaginary line in FIG. An oil pressure sensor 84 may be arranged in an oil passage between the piston chamber 30a1 of the forward clutch 30a and the manual valve 46o or an oil passage communicating with the lock-up clutch 24c of the torque converter 24 to detect the oil pressure at those portions. .

  Moreover, although CVT26 was illustrated as an automatic transmission, it is not restricted to it, A stepped transmission may be used.

  DESCRIPTION OF SYMBOLS 10 Internal combustion engine (engine, drive source), 12 Drive wheel, 14 Vehicle, 16 DBW mechanism, 24 Torque converter, 26 Continuously variable transmission (CVT), 26a, 26b Pulley (friction engagement element), 30 Forward / reverse switching device , 30a Forward clutch (friction engagement element), 46 Hydraulic supply mechanism, 46a Hydraulic pump, 56 Accelerator pedal, 56a Accelerator opening sensor, 58 Brake pedal, 58a Brake switch, 66 Engine controller, 82 Wheel speed sensor, 84 Hydraulic sensor , 90 Shift controller

Claims (5)

  An engine, a hydraulic pump driven by the engine, an automatic transmission that operates with the hydraulic pressure supplied from the hydraulic pump to shift the output of the engine and transmit it to the drive wheels, and when a predetermined condition is satisfied In the vehicle provided with idle stop means for idlingly stopping the engine, a hydraulic pressure change detecting means for detecting a change in hydraulic pressure supplied from the hydraulic pump when the engine is idle stopped, and the detected hydraulic pressure Idle stop duration calculation means for calculating the idle stop duration time for which the idle stop should be continued based on the change of the engine, and engine restart means for restarting the engine when the calculated idle stop duration time has elapsed And a vehicle control device.   2. The vehicle according to claim 1, wherein the hydraulic pressure change detecting unit detects a change in the hydraulic pressure by measuring an elapsed time from when the engine is idle-stopped until the hydraulic pressure drops to a predetermined hydraulic pressure. Control device.   The oil pressure change detecting means detects the change in the oil pressure by measuring an elapsed time until the oil pressure decreases from a predetermined oil pressure to a predetermined oil pressure when the engine is idle-stopped. The vehicle control device according to claim 1.   4. The vehicle control device according to claim 1, wherein the hydraulic pressure change detecting unit detects a change in hydraulic pressure supplied from the hydraulic pump to a friction engagement element of the automatic transmission. .   The vehicle control device according to any one of claims 2 to 4, wherein the predetermined hydraulic pressure is set to a minute value near zero hydraulic pressure.

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