JP5718751B2 - Vehicle control device - Google Patents

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.

  A vehicle that idles the engine when waiting for a signal or the like often includes an electric hydraulic pump separately from the hydraulic pump driven by the engine, and an example thereof is the technique described in Patent Document 1.

  When the electric hydraulic pump is provided, if the electric hydraulic pump fails, it depends on the hydraulic pressure supplied from the hydraulic pump driven by the engine. There is an inconvenience that the shift operation is delayed and the start of the vehicle is delayed.

  Therefore, in the technique described in Patent Document 1, such an inconvenience is solved by adding that the electric hydraulic pump is not out of order to one of the conditions for permitting the idle stop.

Japanese Patent No. 3613989

  The technology described in Patent Document 1 is configured as described above to eliminate the inconvenience at the time of failure of the electric hydraulic pump, but as a result, the opportunity to perform idle stop is reduced and fuel consumption performance is deteriorated. It will cause problems.

  On the other hand, if the idle stop is always executed even when the electric hydraulic pump fails, the vehicle may move backward due to a delay in start response when the vehicle is idle stopped on an uphill / downhill road.

  Therefore, the object of the present invention is to solve the above-mentioned disadvantages, and when the electric hydraulic pump fails, the idle stop is executed as much as possible to avoid the deterioration of the fuel consumption performance, and also due to the delay in the start response on the uphill / downhill road. An object of the present invention is to provide a control device for a vehicle that prevents the vehicle from moving backward.

In order to achieve the above object, according to a first aspect of the present invention, an engine mounted on a vehicle, a hydraulic pump driven by the engine, and a hydraulic pressure supplied from the hydraulic pump are operated to operate the engine. In an automatic transmission that shifts an output and transmits the output to driving wheels, and in a vehicle control device that executes idle stop of the engine when a predetermined permission condition is satisfied, the automatic transmission is hydraulically driven by an electric motor. an electric hydraulic pump for supplying an electric hydraulic pump failure judgment means for judging a failure of the electric hydraulic pump, a hydraulic pressure detecting means for detecting the liquid pressure of the braking device, the gradient of the road the first threshold value and determines to increase as the slope of the traveling road increases from, in the case where the electric hydraulic pump is determined that a failure by the electric hydraulic pump failure judgment unit failure and A first threshold value determining means for determining the larger value as compared with the case not constant, a first tooth, wherein with predetermined permission condition is determined to be satisfied, the detected hydraulic pressure is the determined An idle stop permission means for permitting execution of the idle stop when the threshold value is exceeded is provided.

  In the vehicle control device according to claim 2, when the detected hydraulic pressure is determined to be less than a second threshold value, the brake holding unit holds the braking force of the braking device for a predetermined time. The second threshold value is provided with second threshold value determining means for determining the second threshold value to be a larger value when it is determined that the electric hydraulic pump is out of order than when it is not determined as being out of order.

  In the vehicle control apparatus according to claim 3, the second threshold value determining means is configured to determine the second threshold value from the gradient of the travel path.

  In the vehicle control device according to claim 4, the braking and holding means sets the predetermined time to a larger value when the electric hydraulic pump is determined to be failure than when it is not determined to be failure. Configured as determined.

  In the vehicle control apparatus according to a fifth aspect, the brake holding means is configured to determine the predetermined time from the gradient of the travel path.

In the control apparatus for a vehicle according to claim 6, wherein the first, second threshold determining means, when the gradient of the traveling road is below the predetermined value, the said first, second threshold The same value is determined when the electric hydraulic pump is determined to be faulty and when it is not determined to be faulty.

In the vehicle control device according to claim 1, the first threshold value is determined to increase as the gradient of the travel path increases from the gradient of the travel path, and by the electric hydraulic pump failure determination means Threshold determining means for determining a larger value when the electrohydraulic pump is determined to be faulty than when it is not determined to be faulty, and it is determined that a predetermined permission condition is satisfied and the detected braking When the hydraulic pressure of the apparatus exceeds the determined first threshold value, the apparatus is provided with idle stop permission means for permitting execution of idle stop. Therefore, even when the electric hydraulic pump is out of order, the braking device If the hydraulic pressure exceeds the threshold value, idle stop is executed as long as a predetermined permission condition is satisfied, and deterioration of fuel efficiency can be avoided.

  Also, if an idle stop is executed when the electric hydraulic pump fails, the vehicle may move backward due to a delay in start response when the vehicle idles on an uphill / downhill road, but the threshold is determined from the gradient of the roadway. Thus, it is possible to guarantee the hydraulic pressure required for braking on the uphill / downhill road, and thus it is possible to prevent the vehicle from retreating due to a delay in start response on the uphill / downhill road.

  In the vehicle control device according to claim 2, when it is determined that the detected hydraulic pressure is less than the second threshold value, the braking holding means for holding the braking force of the braking device for a predetermined time; Since the second threshold value determining means for determining the threshold value of 2 to be a larger value when the electric hydraulic pump is determined to be faulty than when the electric hydraulic pump is not determined to be faulty is provided. In addition, it is possible to reliably prevent the vehicle from retreating due to a delayed start response on the uphill / downhill road.

  In the vehicle control apparatus according to claim 3, since the second threshold value determining means is configured to determine the second threshold value from the gradient of the traveling road, in addition to the above effect, the uphill road This makes it possible to more reliably prevent the vehicle from moving backward due to a delay in start response.

  In the vehicle control apparatus according to claim 4, the braking and holding means determines the predetermined time to be a larger value when the electric hydraulic pump is determined to be failure than when it is not determined to be failure. Since it comprised, in addition to the above-described effect, it is possible to more reliably prevent the vehicle from moving backward due to a delay in start response when the electric hydraulic pump is out of order.

  In the vehicle control device according to the fifth aspect, since the braking holding means is configured to determine the predetermined time from the gradient of the travel path, in addition to the above-described effect, the braking hydraulic means can be used when the electric hydraulic pump is out of order. It is possible to more reliably prevent the vehicle from retreating due to a delay in start response on the uphill / downhill road.

In the control apparatus for a vehicle according to claim 6, first, second threshold determining means, when the gradient of the traveling road is below the predetermined value, the first, the second threshold electric hydraulic pump Since the same value is determined for the case where it is determined that there is a failure and the case where it is not determined that there is a failure, in addition to the effects described above, the driver does not feel uncomfortable by operating the braking device.

  That is, the threshold value is determined to increase from the gradient of the road, for example, as the gradient increases, so that it is possible to prevent the vehicle from moving backward due to a delay in start response when the vehicle is idle-stopped on an uphill / downhill road. For example, on a flat road where the slope of the vehicle is equal to or less than a predetermined value, there is no fear of such a reverse of the vehicle.

  Therefore, by determining the threshold value to the same value when the electric hydraulic pump is determined to be faulty on a flat road or the like, the driver can detect the braking device only by applying the same pedaling force to the braking device. It is possible to idle stop when the hydraulic pressure exceeds the threshold value, and there is no sense of incongruity that the required pedaling force is different depending on whether or not the electric hydraulic pump is determined to be faulty.

1 is a schematic diagram showing an overall control apparatus for a vehicle according to an embodiment of the present invention. FIG. 2 is a hydraulic circuit diagram of the brake fluid pressure supply mechanism shown in FIG. 1. FIG. 2 is a hydraulic circuit diagram of the transmission hydraulic pressure supply mechanism shown in FIG. 1. It is a flowchart which shows operation | movement of the apparatus shown in FIG. 4 is an explanatory diagram showing characteristics such as brake permission hydraulic pressure used in the processing of the flow chart. It is explanatory drawing which shows calculation of the gradient of the traveling path used for the characteristic search of FIG. 4 is a time chart for explaining the processing of the flow chart. 4 is a flow chart showing the operation of the apparatus shown in FIG. 1 executed in parallel with the flow chart.

  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 a vehicle control apparatus according to an embodiment of the present invention, FIG. 2 is a brake hydraulic pressure supply mechanism shown in FIG. 1, and FIG. 3 is a hydraulic pressure of a transmission hydraulic pressure supply mechanism shown in FIG. It is a circuit diagram.

  In FIG. 1, the code | symbol 10 shows an engine (internal combustion engine). The engine 10 is mounted on a vehicle 14 provided with drive wheels 12 (the vehicle 14 is partially indicated by the drive wheels 12 and the like).

A throttle valve (not shown) arranged in the intake system of the engine 10 is disconnected from the accelerator pedal arranged on the vehicle driver's seat floor surface, and DBW (Drive By Wire) comprising an actuator such as an electric motor is disconnected. ) Connected to the mechanism 16 and opened and closed by the DBW mechanism 16.

  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 discharged to the outside of the engine 10 as exhaust gas.

  The rotation of the crankshaft 22 is input to the automatic transmission 26 via the torque converter 24. The automatic transmission 26 includes a continuously variable transmission (hereinafter referred to as “CVT”) 26.

  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 is a main shaft MS, more precisely, a drive pulley 26a disposed on the outer peripheral side shaft, and a counter shaft (output shaft) CS parallel to the main shaft MS, more precisely, a driven disposed on the outer peripheral side shaft. The pulley 26b and an endless flexible member, for example, a metal belt 26c, hung around the pulley 26b.

  The drive pulley 26a is fixed to the stationary pulley half 26a1 which is disposed so as not to be rotatable relative to the outer peripheral shaft of the main shaft MS and is not movable in the axial direction, and to the fixed pulley half 26a1 which is not rotatable relative to the outer peripheral shaft of the main shaft MS. The movable pulley half 26a2 is relatively movable in the axial direction.

  The driven pulley 26b includes a fixed pulley half 26b1 that is not rotatable relative to the outer peripheral shaft of the counter shaft CS and is not movable in the axial direction, and an axial direction relative to the fixed pulley half 26b1 that is not rotatable relative to the counter shaft CS. The movable pulley half 26b2 is relatively movable.

  The CVT 26 is connected to the engine 10 via a forward / reverse switching mechanism 28. The forward / reverse switching mechanism 28 includes a forward clutch 28a that allows the vehicle 14 to travel in the forward direction, a reverse brake clutch 28b that allows the vehicle 14 to travel in the reverse direction, and a planetary gear mechanism 28c disposed therebetween. CVT 26 is connected to engine 10 via forward clutch 28a.

  In the planetary gear mechanism 28c, the sun gear 28c1 is fixed to the main shaft MS, and the ring gear 28c2 is fixed to the fixed pulley half 26a1 of the drive pulley 26a via the forward clutch 28a.

  A pinion 28c3 is disposed between the sun gear 28c1 and the ring gear 28c2. Pinion 28c3 is connected to sun gear 28c1 by carrier 28c4. When the reverse brake clutch 28b is operated, the carrier 28c4 is fixed (locked) thereby.

  The rotation of the countershaft CS is transmitted from the secondary shaft (intermediate shaft) SS to the drive wheels 12 via a gear. That is, the rotation of the countershaft CS is transmitted to the secondary shaft SS via the gears 30a and 30b, and the rotation is transmitted from the differential 32 to the left and right drive wheels (only the right side is shown) 12 via the gear 30c.

  A disc brake (braking device) 34 is disposed in the vicinity of the driving wheel (front wheel) 12 and the driven wheel (rear wheel, not shown). The disc brake 34 includes a caliper 34a and a disc 34b.

  A brake pedal 36 is disposed on the vehicle driver's seat floor. The brake pedal 36 is connected to a master brake 38, a master cylinder 40, and a disc brake 34 connected via a brake hydraulic pressure supply mechanism 42. The master cylinder 40 includes a reservoir 40a that stores brake fluid, and a piston (not shown) that is slidable in an oil chamber filled with the brake fluid stored in the reservoir 40a.

  When the driver depresses the brake pedal 36, the depressing force is increased by the master back 38 and transmitted to the master cylinder 40. The piston of the master cylinder 40 strokes a distance corresponding to the increased stepping force. The fluid pressure (brake fluid pressure) generated by the stroke of the piston is sent to the brake fluid pressure supply mechanism 42.

  As shown in FIG. 2, in the brake hydraulic pressure supply mechanism 42, it is sent from the fluid path 42a to the linear solenoid valve (electromagnetic solenoid valve) 42b, and then sent to the disc brakes 34 of the left and right drive wheels 12 via the fluid paths 42c and 42d. It is done. The hydraulic pressure generated through the liquid passage 42e is sent to the driven wheel (rear wheel) side.

  The spool of the linear solenoid valve 42b is movable between a communication position where the liquid passage 42a communicates with the liquid passages 42c and 42d and a shut-off position. The solenoid 42b1 is energized and subjected to PWM control to an arbitrary amount. Is sent as a caliper pressure to a piston (not shown) of a caliper 34a of the disc brake 34, the disc 34b is pressed by the piston, the disc brake 34 is operated, and the vehicle 14 is braked (decelerated).

  Returning to the description of FIG. 1, in the forward / reverse switching mechanism 28, the forward clutch 28a and the reverse brake clutch 28b are switched by the driver operating a range selector 44 provided in the vehicle driver's seat, for example, P, R, N, This is done by selecting one of the ranges such as D. The range selection by the driver's operation of the range selector 44 is transmitted to a manual valve of a transmission hydraulic pressure supply mechanism 46 (described later).

  When, for example, the D, S, or L range is selected via the range selector 44, the spool of the manual valve moves accordingly, and hydraulic oil (hydraulic pressure) is discharged from the piston chamber of the reverse brake clutch 28b, while the forward drive Hydraulic pressure is supplied to the piston chamber of the clutch 28a, and the forward clutch 28a is fastened.

  When the forward clutch 28a is engaged, all the 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, so that the vehicle 14 travels in the forward direction.

  When the R range is selected, hydraulic oil is discharged from the piston chamber of the forward clutch 28a, while hydraulic pressure is supplied to the piston chamber of the reverse brake clutch 28b, and the reverse brake clutch 28b is operated. Accordingly, the carrier 28c4 is fixed, the ring gear 28c2 is driven in the opposite direction to the sun gear 28c1, the drive pulley 26a is driven in the opposite direction (reverse direction) to the main shaft MS, and the vehicle travels in the reverse direction.

  When the P or N range is selected, the hydraulic oil is discharged from both piston chambers, both the forward clutch 28a and the reverse brake clutch 28b are released, the power transmission via the forward / reverse switching device 28 is cut off, and the engine The power transmission between the motor 10 and the drive pulley 26a of the CVT 26 is cut off.

  FIG. 3 is a hydraulic circuit diagram of the transmission hydraulic pressure supply mechanism 46.

  As illustrated, the transmission 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 (E) 10, pumps up the hydraulic oil stored in the reservoir 46b, and pumps it to the 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.

  Accordingly, a 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. Thus, by adjusting the pulley side pressure, the ratio (transmission ratio) for transmitting the output of the engine 10 to the drive wheels 12 can be changed steplessly.

CR output valve 46h (CR pressure) to the third linear solenoid valve (LS-CPC) pressure is regulated depending on the excitation of the solenoid of 46l, the manual valve (MAN VLV that describes front through an oil passage 46m. Code 46o Are connected to the piston chamber (FWD) 28a1 of the forward clutch 28a of the forward / reverse switching device 28 and the piston chamber (RVS) 28b1 of the reverse brake clutch 28b.

As described above, the manual valve 46o outputs the output adjusted by the third linear solenoid valve 46l in accordance with the position of the range selector 44 operated (selected) by the driver, and the pistons of the forward clutch 28a and the reverse brake clutch 28b. Connect to one of the chambers 28a1 and 28b1.

  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 on the one hand to the piston chamber 24c1 of the lock-up clutch 24c of the torque converter 24, and on the other hand to the backside chamber 24c2.

  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.

  Further, an EOP (Electric Oil Pump) 46w connected to the electric motor 46v is connected via a check valve 46x at a position corresponding to the downstream of the hydraulic pump 46a and upstream of the PH control valve 46c.

  Similarly to the hydraulic pump 46a, the EOP 46w is also composed of a gear pump, is driven by an electric motor 46v, pumps up the hydraulic oil stored in the reservoir 46b, and pumps it to the PH control valve (PH REG VLV) 46c.

  In this specification, the automatic transmission includes a torque converter 24, a CVT 26, and a forward / reverse switching mechanism 28 (more specifically, its forward clutch 28a (or reverse brake clutch 28b)).

  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 (indicated by reference numeral 56) to output a signal proportional to the accelerator opening AP corresponding to the driver's accelerator pedal operation amount, and to the brake pedal 36. Is provided with a brake switch 36a that outputs an ON signal in response to the driver's operation of the brake pedal 36.

  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. The rotational speed of the turbine runner 24b, specifically, the rotational speed NT (transmission input shaft rotational speed) of the main shaft MS, more specifically, A pulse signal indicating the input shaft speed of the forward clutch 28a is output.

  An NDR sensor (rotational speed sensor) 72 is provided at an appropriate position in the vicinity of the drive pulley 26a of the CVT 26 to output a pulse signal corresponding to the rotational speed NDR of the drive pulley 26a, in other words, the output shaft rotational speed of the forward clutch 28a. To do.

  An NDN sensor (rotational speed sensor) 74 is provided at an appropriate position near the driven pulley 26b, and a pulse signal indicating the rotational speed NDN of the driven pulley 26b, that is, the rotational speed of the counter shaft CS (transmission output shaft rotational speed). And a V sensor (rotational speed sensor) 76 is provided in the vicinity of the gear 30b of the secondary shaft SS to output a pulse signal indicating the vehicle speed V through the rotational speed of the secondary shaft SS.

  A range selector switch 44a is provided in the vicinity of the above-described range selector 44, and outputs a signal corresponding to a range such as R, N, or D selected by the driver.

  As shown in FIG. 2, in the brake fluid pressure supply mechanism 42, a fluid pressure sensor 80 is disposed in the fluid path between the master cylinder 40 and the linear solenoid valve 42b, and the fluid pressure of the disc brake 34, specifically, the master cylinder 40 A signal corresponding to the hydraulic pressure (master cylinder pressure) generated by

  In addition, as shown in FIG. 3, a hydraulic pressure sensor 82 is disposed in an oil passage that communicates with the driven pulley 26b of the CVT 26 in the hydraulic pressure supply mechanism 46, and the hydraulic pressure supplied to the piston chamber 26b21 of the movable pulley half 26b2 of the driven pulley 26b. A corresponding signal is output. An oil temperature sensor 84 is disposed in the reservoir 46b and outputs a signal corresponding to the oil temperature (temperature TATF of the hydraulic oil ATF).

  The oil pressure sensor 82 is arranged in an oil passage between the piston chamber 28a1 of the forward clutch 28a and the manual valve 46o or an oil passage leading to the lock-up clutch 24c of the torque converter 24, as indicated by an imaginary line in FIG. The hydraulic pressure of the part may be detected.

  A tilt sensor 86 is provided in the vicinity of the center position of the vehicle 14, and generates an output indicating the gradient of the travel path on which the vehicle 14 travels through the front-rear (vehicle length) tilt of the vehicle 14.

  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.

Shift controller 90 on the basis of their detected values, the first speed change machine hydraulic pressure supply mechanism 46 fourth linear solenoid valves 46j, 46k, 46l, forward-reverse switching device is excited and non-excited electromagnetic solenoid, such as 46u 28, CVT 26, and the operation of the torque converter 24 are controlled.

  Further, the shift controller 90 determines an energization amount of the electric motor 46v of the transmission hydraulic pressure supply mechanism 46 based on the detected values, and energizes the electric motor 46v via a drive circuit (not shown) to drive the EOP 46w. .

  Further, the engine controller 66 performs idle stop control of the vehicle 14 in addition to fuel injection control and the like.

  FIG. 4 is a flowchart showing the operation of the apparatus according to this embodiment, specifically, idle stop (IS) control of the engine controller 66, and more specifically, permission / prohibition of the idle stop. The illustrated program is executed every predetermined time, for example, every 10 msec.

  In the following, it is determined in S10 whether an IS (idle stop) permission condition is satisfied.

  The IS (idle stop) permission condition is that the brake pedal 36 is operated (depressed) by the driver, the accelerator pedal 56 is not operated (not depressed), and the vehicle speed V is zero. This is true when the ratio (transmission ratio) of the CVT 26 is low and all of them are satisfied.

  The success or failure of the above condition is determined from information obtained by communicating with the output of the brake switch 36a, the accelerator opening sensor 56a, the V sensor 76 and the shift controller 90.

  When the result in S10 is negative, the subsequent processing is skipped. When the result is affirmative, the process proceeds to S12 to determine whether or not the EOP 46w is normal. This is determined by detecting the temperature of the drive circuit of the electric motor 46v that drives the EOP 46w with a temperature sensor appropriately arranged.

  Specifically, when the detected temperature of the drive circuit exceeds a specified value, it is determined that the drive circuit, that is, the electric motor 46v is abnormal, and thus the EOP 46w connected thereto is also abnormal.

  When the result in S12 is affirmative and it is determined that the EOP 46w is normal, the process proceeds to S14, where the brake permission hydraulic pressure 1 is calculated from the gradient of the travel path. More specifically, the brake permission hydraulic pressure 1 is calculated by searching the characteristic shown in FIG. 5 (the brake permission hydraulic pressure characteristic during normal EOP) from the gradient of the traveling path detected by the output of the inclination sensor 86.

  On the other hand, when the result in S12 is negative and the EOP 46w is not normal, that is, when it is determined that there is a failure, the process proceeds to S16, and the brake permission hydraulic pressure 2 is similarly calculated from the gradient of the travel path. More specifically, the brake permission hydraulic pressure 2 is calculated by searching the characteristic (brake permission hydraulic pressure characteristic at the time of EOP failure) shown in the same figure from the gradient of the traveling path similarly detected by the output of the inclination sensor 86.

  As shown in the figure, the brake permitting hydraulic pressures 1 and 2 are set so as to be searchable from the gradient of the traveling road. When the gradient is a minute value (5%) or less, the brake permission hydraulic pressures 1 and 2 are set to the same (constant) values. After exceeding, it is set to increase as the gradient increases.

  Further, as apparent from FIG. 5, the brake permission hydraulic pressure 2 is set larger than the brake permission hydraulic pressure 1 after the gradient exceeds a minute value. That is, the brake permission characteristic is set to be larger when the EOP 46w is determined to be malfunctioning (at the time of failure) than when the EOP 46w is not determined to be malfunctioning (at the time of normal operation).

  That is, the brake permitting hydraulic pressures 1 and 2 are set to the same value when the slope of the travel path is equal to or less than a predetermined value, when the EOP 46w is determined to be faulty and when it is not determined to be faulty. When the slope exceeds a predetermined value, the EOP 46w is set to be larger when it is determined as failure than when it is not determined as failure, so that the first threshold value has the same characteristic as described later. Is done.

  The gradient of the traveling road is obtained from the output of the inclination sensor 86, but instead, the gradient of the traveling road may be calculated (detected) by calculation as shown in FIG. The gradient of the travel path is expressed by 100 × vertical distance [m] / horizontal distance [m].

  In the flowchart of FIG. 4, the process then proceeds to S18, where the calculated brake permission hydraulic pressure 1 or 2 is determined (set) as the first threshold value.

  Next, in S20, the hydraulic pressure (master cylinder pressure) of the disc brake 34 detected from the hydraulic pressure sensor 80 exceeds the first threshold value (brake permission hydraulic pressure 1 or 2) determined (set) in S18. If the result is affirmative, the process proceeds to S22, and IS (idle stop) is permitted. If the result is negative, the process proceeds to S24, and IS is prohibited.

  FIG. 7 is a time chart for explaining the operation of the flowchart of FIG.

  As shown in the figure, the hydraulic pressure (master cylinder pressure) of the master cylinder 40, which is increased by the driver's operation of the brake pedal 36, exceeds a first threshold value (brake permission hydraulic pressure 1 or 2) at time t1, for example. If the condition described in S10 is also satisfied, IS (idle stop) is permitted (engine 10 is stopped).

  FIG. 8 is a flow chart showing the operation of the apparatus according to this embodiment, specifically, the brake holding control executed by the engine controller 66 in parallel with the idle stop control of FIG. The illustrated program is also executed every predetermined time, for example, every 10 msec.

  In the following, it is determined whether or not the EOP 46w is normal in S100. This is determined by the same method as described in S12.

  When the result in S100 is affirmative and it is determined that the EOP 46w is normal, the process proceeds to S102, and the brake holding hydraulic pressure 1 is calculated from the gradient of the travel path, similarly to the processing from S12 to S14.

  More specifically, the brake holding hydraulic pressure 1 is calculated by searching the brake holding hydraulic pressure characteristic during normal EOP shown in FIG. Next, in S104, a similar characteristic (not shown) is searched from the detected gradient of the traveling path to determine (calculate) a holding time (predetermined time) 1.

  Further, when the result in S100 is negative and it is determined that the EOP 46w is out of order, the process proceeds to S106, and the brake holding hydraulic pressure 2 is calculated from the gradient of the travel path. Specifically, the brake holding hydraulic pressure characteristic at the time of EOP failure shown in FIG. 5 is searched from the detected road gradient to calculate the brake holding hydraulic pressure 2, and the process proceeds to S108, from the detected road gradient. A similar characteristic (not shown) is searched to determine (calculate) a holding time (predetermined time) 2.

  As shown in the figure, the brake holding fluid pressures 1 and 2 are also set so as to be searchable from the gradient of the travel path, and are set to the same (constant) value when the gradient is equal to or less than a predetermined value (minute value (5%)). After that, it is set to increase as the gradient increases.

  Also, the brake holding fluid pressures 1 and 2 are similar to the brake permitting fluid pressure, and when the EOP 46w has failed after the gradient exceeds a minute value (when "brake holding fluid pressure 2 at failure" is indicated). The EOP 46w is set to be larger than when the EOP 46w is not out of order (in the case of “normal brake holding hydraulic pressure 1”).

  That is, the brake holding hydraulic pressures 1 and 2 are also set to the same value when the slope of the travel path is equal to or less than a predetermined value, when the EOP 46w is determined to be faulty and when it is not determined to be faulty. When the slope exceeds a predetermined value, the EOP 46w is determined to be larger when it is determined as failure than when it is not determined as failure, so that the second threshold value has the same characteristics as described later. Is done.

  The holding times 1 and 2 (predetermined time) mean the time during which the disc brake 34 should hold the brake (braking) operation. As shown in the time chart of FIG. 7, the holding time is also the time when the EOP 46w is out of order. The holding time 2 is set longer than the holding time 1 in the case where it is not.

  Although the illustration of the characteristics is omitted, the holding times 1 and 2 are also set so as to be searchable from the gradient of the travel path, and are set to the same (constant) value when the gradient is equal to or less than a predetermined value (minute value (5%)). At the same time, it is set to increase as the gradient increases.

  In the flowchart of FIG. 8, the process then proceeds to S110, where the calculated brake holding fluid pressure 1 (or 2) is determined (set) as the second threshold value. Next, in S112, it is determined whether or not the hydraulic pressure (master cylinder pressure) detected from the hydraulic pressure sensor 80 is less than the second threshold value (brake holding hydraulic pressure 1 or 2) determined (set) in S110. .

  When the result in S112 is negative, the subsequent processing is skipped. When the result is affirmative, the process proceeds to S114, during the set holding time 1 (or 2), during the brake operation, that is, during the set holding time. The disc brake 34 is operated to maintain the braking force. In other words, during the set holding time, the linear solenoid valve 42b is continuously energized, and the hydraulic pressure is continuously supplied to the disc brake 34 to hold the braking force.

As described above, in this embodiment, the engine 10 mounted on the vehicle 14, the hydraulic pump 46a driven by the engine, and the hydraulic pressure supplied from the hydraulic pump 46a operate to output the engine. An electric motor in a CVT (automatic transmission) 26 that changes the speed of the engine 10 and transmits it to the drive wheels 12 and a vehicle control device (engine controller) 90 that executes idle stop of the engine 10 when a predetermined permission condition is satisfied. EOP (electric hydraulic pump) 46w that is driven by 46v and supplies hydraulic pressure to the CVT 26, EOP failure determination means (S12) for determining failure of the EOP 46w, and hydraulic pressure (for example, master) of the disc brake (braking device) 34 hydraulic pressure detecting means for detecting a cylinder pressure) and (hydraulic pressure sensor 80), the first threshold value (first threshold value. blur With a gradient of keys allow hydraulic 1,2) the travel path from the slope of the road the is determined so as to increase with increasing, when said by the EOP failure determining means EOP46w is determined to failure faults and First threshold value determining means (S12 to S18) for determining a larger value than when not determined, and it is determined that the predetermined permission condition is satisfied (S10), and the detected hydraulic pressure is When the determined first threshold value is exceeded (S20), the idle stop permission means (S22) for permitting the execution of the idle stop is provided. Therefore, even if the EOP 46w fails, the disk If the hydraulic pressure of the brake 34 exceeds the (first) threshold value, the idle stop is executed as long as a predetermined permission condition is satisfied, and the fuel efficiency is improved. It is possible to avoid the deterioration.

  Further, if idle stop is executed at the time of failure of EOP46w, the vehicle 14 may move backward (or move forward) due to a delay in start response when the vehicle 14 idles on an uphill / downhill road, but the (first) threshold. By determining the value from the slope of the roadway, it becomes possible to guarantee the hydraulic pressure required for braking on the uphill / downhill road, and therefore the reverse (or forward, especially uphill) due to the delay in start response on the uphill / downhill road. (Retreat on the road) can be prevented.

  That is, as described at the beginning, if EOP46w is not out of order in one of the conditions for allowing the idling stop as in the technique described in Patent Document 1, the opportunity for executing the idling stop is reduced and the fuel consumption performance is reduced. If the vehicle 14 stops on an uphill / downhill road, there is a risk that the vehicle will move backward (or move forward) due to a delay in start response, if the idle stop is always executed even when the EOP 46w fails to avoid it.

  In this embodiment, therefore, separately from the idling stop permission condition, the detected brake fluid pressure (first threshold) is determined based on the gradient of the travel path. 7), for example, if the hydraulic pressure detected at time t1 exceeds the brake allowable hydraulic pressure (first threshold value), an idle stop is permitted as shown in FIG. (S20, S22).

  Further, as shown in FIG. 5, when the EOP 46w has failed, the brake permitting hydraulic pressure is set to be larger than that when the EOP 46w has failed. Since it is difficult to permit the stop, in addition to the above-described effects, it is possible to reliably prevent the vehicle 14 from retreating due to a delay in start response on the uphill / downhill road regardless of the gradient.

  When it is determined that the detected hydraulic pressure is less than the second threshold value (S112), the brake holding means (S104) holds the braking force of the disc brake 34 for the holding time 1, 2 (predetermined time). , S108, S114) and second threshold value determining means (S100, S114) for determining the second threshold value to be a larger value when the EOP 46w is determined to be failure than when it is not determined to be failure. S102, S106, S110), the vehicle 14 can be reliably prevented from retreating (or moving forward) due to a delayed start response on the uphill / downhill road in addition to the above-described effects.

  Further, since the second threshold value determining means is configured to determine the second threshold value from the gradient of the traveling road (S102, S106, S110), in addition to the above-described effects, Regardless of the slope, it is possible to more reliably prevent the vehicle 14 from retreating (or moving forward) due to a delayed start response.

  Therefore, in the time chart of FIG. 7, for example, when it is determined that the hydraulic pressure (master cylinder pressure) detected at time t2 is less than the brake holding hydraulic pressure (second threshold value), the failure of the EOP 46w (or The caliper pressure continues to be sent to the piston of the disc brake 34 for the holding time determined by (normal).

  As a result, for example, at time t3, the brake switch (SW) 36a is turned off, the driver removes his / her foot from the brake pedal 36, and the engine (ENG) 10 is requested to start, and a start delay (DLY) is generated only at time t4. Even if the hydraulic pressure supply operation from the hydraulic pump 46a is delayed, the supply of the caliper pressure of the disc brake 34 is continued.

  Therefore, even if the start response is delayed due to the failure of the EOP 46w, the disc brake 34 is operated during the set holding time when the detected hydraulic pressure falls below the brake holding hydraulic pressure. Even if the vehicle stops on the uphill / downhill road, it is possible to reliably prevent the backward movement.

  In addition, the braking and holding means is configured to determine the holding times 1 and 2 (predetermined time) to be larger values when the EOP 46w is determined to be failure than when it is not determined to be failure. In addition to the effects described above, it is possible to more reliably prevent the vehicle 14 from retreating due to a delay in start response when the EOP 46w is out of order.

  Further, since the braking and holding means is configured to determine the holding times 1 and 2 (predetermined time) from the gradient of the travel path (S104, S106, S104, and S108), in addition to the above-described effects, the EOP 46w fails. It is possible to more reliably prevent the vehicle 14 from retreating due to a delay in start response on the uphill / downhill road.

The first, second threshold determination means, the gradient of the traveling road is a predetermined value (small value (5%)) when: the first, the second threshold value the EOP46w failure and Since the same value is determined for the case where the determination is made and the case where the failure is not determined, in addition to the effects described above, the driver does not feel uncomfortable by operating the disc brake 3434.

  That is, by determining the threshold value from the gradient of the traveling road so as to increase as the gradient increases, as shown in FIG. 5, the vehicle 14 is caused by a delay in start response when the vehicle 14 is idle-stopped on an uphill / downhill road. Although it is possible to prevent the vehicle from moving backward, there is no fear of the vehicle 14 moving backward on a flat road (or a substantially flat road) where the gradient of the traveling road is a predetermined value or less.

  Therefore, the driver only applies the same pedaling force to the disc brake 34 by determining the threshold value on the flat road (or almost flat road) to the same value depending on whether or not the EOP 46w is determined to be faulty. As a result, the detected hydraulic pressure of the disc brake 34 exceeds the threshold value, and the idling can be stopped, and there is no sense of incongruity that the required pedaling force is different depending on whether or not the EOP 46w is determined to be faulty.

  In the above description, the brake permission hydraulic pressures 1 and 2 (first threshold value) are calculated (determined) by searching for a preset characteristic from the gradient of the travel path. However, the present invention is not limited to this. Alternatively, it may be calculated (determined) directly from the gradient of the travel path by calculation or the like.

  The brake holding fluid pressures 1 and 2 (second threshold value) are also calculated (determined) by searching for a preset characteristic from the gradient of the travel path. It may be calculated (determined) directly from the gradient of the road by calculation or the like. The same applies to holding times 1 and 2 (predetermined time).

  Further, the fluid pressure of the disc brake 34 is detected from the master cylinder pressure, but instead it can be detected from any parameter indicating the fluid pressure of the disc brake 34, such as a caliper pressure. .

  Moreover, although CVT was illustrated as an automatic transmission, it is not restricted to it, A stepped transmission may be used. Furthermore, the endless flexible member of the CVT is not limited to the belt, but may be a chain.

  DESCRIPTION OF SYMBOLS 10 Engine (internal combustion engine), 12 Drive wheel, 14 Vehicle, 16 DBW mechanism, 24 Torque converter, 26 Automatic transmission (CVT), 28 Forward / reverse switching device, 34 Disc brake (braking device), 36 Brake pedal, 38 Master Back, 40 master cylinder, 42 brake hydraulic pressure supply mechanism, 42b linear solenoid valve, 46 transmission hydraulic pressure supply mechanism, 46a hydraulic pump, 46w EOP (electric hydraulic pump), 66 engine controller, 76 V sensor, 80 hydraulic pressure sensor, 82 Hydraulic sensor, 86 Tilt sensor, 90 Shift controller

Claims (6)

An engine mounted on a vehicle, a hydraulic pump driven by the engine, an automatic transmission that operates with a hydraulic pressure supplied from the hydraulic pump and shifts an output of the engine and transmits the output to driving wheels; In a vehicle control device that executes idle stop of the engine when a permission condition is satisfied, an electric hydraulic pump that is driven by an electric motor and supplies hydraulic pressure to the automatic transmission, and a failure of the electric hydraulic pump is determined. The hydraulic pressure pump failure determination means, the hydraulic pressure detection means for detecting the hydraulic pressure of the braking device, and the first threshold value are determined so as to increase from the gradient of the travel path as the gradient of the travel path increases. , first said determining to a large value if the electric hydraulic pump is determined that a failure by the electric hydraulic pump failure judgment means than when it is not determined that the failure And have value determining means, wherein with a given authorization condition is judged to be satisfied, when the detected hydraulic pressure exceeds the first threshold that is the determined idle to allow execution of the idle stop A vehicle control device comprising stop permission means.   When it is determined that the detected hydraulic pressure is less than the second threshold value, the brake holding means for holding the braking force of the braking device for a predetermined time, and the electric hydraulic pump sets the second threshold value. 2. The vehicle control apparatus according to claim 1, further comprising a second threshold value determining unit that determines a larger value when it is determined as a failure than when it is not determined as a failure.   The vehicle control device according to claim 2, wherein the second threshold value determining means determines the second threshold value from a gradient of the travel path.   3. The vehicle according to claim 2, wherein the brake holding unit determines the predetermined time to be a larger value when the electric hydraulic pump is determined to be faulty than when the electric hydraulic pump is not determined to be faulty. Control device.   The vehicle control device according to claim 2, wherein the brake holding unit determines the predetermined time from a gradient of the travel path. Said first, second threshold determining means, when the gradient of the traveling road is below the predetermined value, the first, and if the second the electric hydraulic pump threshold is determined to be a failure faults and The vehicle control device according to claim 2 , wherein the same value is determined for the case where the determination is not made.

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