JP2009293498A - Shift-by-wire controller for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for a vehicle securing safety and suppressing deterioration of convenience of a driver when anomaly regarding shift-by-wire control is detected. <P>SOLUTION: If either one of a first reception determining means 142 and a second reception determining means 144 determines that an anomaly detection result of an anomaly detecting means 132 has been acquired, a power transmission allowing means 146 gives power transmission authorization to a driving force control means 154, and by the authorization, a driving force limiting means 154 carries out driving force limiting control of limiting driving force of the vehicle. Then, in a driving force restoring means 156, for example, after passage of a predetermined driving force limiting time_df from starting of the driving force limiting control, driving force of the vehicle is raised up to an intermediate driving force F<SB>MD</SB>lower than normal times. By this, the driver can recognize that the driving force of the vehicle is limited by the driving force limiting control and safety is secured, and thereafter, the limiting of the driving force is eased and the deterioration of the driver's convenience can be suppressed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fail-safe technique used when an abnormality of a shift-by-wire control device for a vehicle is detected.

  2. Description of the Related Art Conventionally, a shift-by-wire control device for a vehicle that employs a so-called shift-by-wire (SBW) that transmits an electric control signal for vehicle shift control or the like is known. For example, the shift-by-wire control device for a vehicle described in Patent Document 1 is this. The shift-by-wire control device for a vehicle described in Patent Document 1 is composed of a plurality of shift-by-wire control circuits and a control circuit different from them, and a monitoring control means for monitoring the shift-by-wire control circuit, and its monitoring And a permission / refusal means for individually permitting or prohibiting the control executed by the plurality of shift-by-wire control circuits based on a command from the control means.

According to the shift-by-wire control device for a vehicle disclosed in Patent Document 1, when an abnormality occurs in a part of the plurality of shift-by-wire control circuits, the monitoring control unit includes an abnormal shift-by-wire control circuit and a normal shift-by-wire control circuit. Identify the control circuit. Further, the permission / refusal means permits the normal shift-by-wire control circuit to continue control based on the identification result of the monitoring control means, and controls the abnormal shift-by-wire control circuit. Is prohibited. In such a case, the monitoring control means implements engine output restriction that reduces engine torque or stops the engine.
JP 2006-335157 A

  In the vehicle shift-by-wire control device disclosed in Patent Document 1, the engine output restriction is performed when an abnormality occurs in a part of the plurality of shift-by-wire control circuits. If this engine output restriction continues for a long time, the convenience of the driver is deteriorated (decreased). However, the shift-by-wire control device disclosed in Patent Document 1 implements it without any limitation on the duration of the engine output limitation, and the convenience of the driver may be deteriorated more than necessary. It was. This problem is not yet known.

  The present invention has been made against the background of the above circumstances, and its purpose is to drive while ensuring safety in vehicle travel when an abnormality (failure, failure) related to shift-by-wire control is detected. It is providing the shift-by-wire control apparatus of the vehicle which suppresses that a user's convenience deteriorates (decreases).

  In order to achieve this object, in the invention according to claim 1, (a) a first control unit that outputs a control signal related to vehicle travel, and a second control unit that executes control related to vehicle travel based on the control signal; , A shift-by-wire control device for a vehicle including a communication path for transmitting the control signal between the first control unit and the second control unit, wherein (b) the communication paths are parallel to each other. A path and a second path, (c) the first control unit includes an abnormality detection means for detecting an abnormality of the shift-by-wire control device, and (d) the second control unit includes the first path and the second path. If the abnormality detection result of the abnormality detecting means indicating the abnormality is not obtained via one communication path of the second route and the abnormality detection result is obtained via the other communication route, the vehicle Any communication From the start of the driving force limiting control, the driving force limiting means for executing the driving force limiting control for limiting the driving force of the vehicle lower than the normal driving force when the abnormality detection result is not obtained Driving force recovery means for executing driving force recovery control for making the driving force of the vehicle lower than the normal driving force and higher than the driving force in the driving force limit control after a predetermined driving force limit time elapses; Is included.

  Further, in the invention according to claim 2, the driving force recovery means increases the driving force of the vehicle at a predetermined change rate as time elapses after the driving force limit control is started in the driving force recovery control. It is characterized by.

  In the invention according to claim 3, the driving force recovery means changes the change rate so that the driving force of the vehicle increases faster as the vehicle speed increases in the driving force recovery control. .

  Further, the invention according to claim 4 is characterized in that the driving force at the time of the driving force limiting control is a predetermined vehicle driving force set as low as possible so that the vehicle can run.

  In the invention according to claim 5, (a) when the second control unit obtains the abnormality detection result via the other communication path, the driving force limiting control by the driving force limiting means is performed. (B) the driving force limiting means does not obtain the abnormality detection result via the one communication path, and does not obtain the abnormality detection result via the other communication path. When obtaining the abnormality detection result continues for a predetermined time, the power shut-off means is stopped from shutting off the power transmission path, and the driving force limiting control is executed.

  According to the shift-by-wire control device for a vehicle of the invention according to claim 1, the communication path includes a first path and a second path that are parallel to each other, and the first control unit is an abnormality of the shift-by-wire control apparatus. Including an abnormality detecting means for detecting. Further, the second control unit (a) does not obtain an abnormality detection result of the abnormality detecting means indicating the abnormality via one communication path of the first route and the second route, and determines the other communication route. If the abnormality detection result is obtained through the vehicle, the vehicle is lower than the normal driving force when the abnormality detection result is not obtained through any communication path in a state where the vehicle can generate the driving force. (B) driving force limiting means for limiting the driving force of the vehicle, and (b) the driving force of the vehicle from the normal driving force after a predetermined driving force limit time has elapsed since the start of the driving force limiting control. Driving force recovery means for executing a driving force recovery control that makes the driving force lower and higher than the driving force at the time of the driving force limiting control, so that when the above abnormality detection result is obtained, The above driving force is On which is provided a grace capable of recognizing the driver that has been limited, the driving force becomes that is relaxed its limit is close to the normal-time driving force. As a result, it is possible to prevent the driver's convenience from deteriorating while ensuring safety in vehicle travel.

  According to the shift-by-wire control device for a vehicle of the invention according to claim 2, the driving force recovery means in the driving force recovery control, the vehicle at a predetermined rate of change over time after the start of the driving force limit control. Therefore, the driving force of the vehicle does not change suddenly, and sufficient safety can be ensured when the driving force of the vehicle increases.

  The driver usually suppresses the vehicle speed if there is an obstacle or the like near the vehicle, and increases the vehicle speed if there is no such obstacle or the safety is sufficiently high. In this regard, according to the shift-by-wire control device for a vehicle of the invention according to claim 3, the driving force recovery means is configured so that, in the driving force recovery control, the driving force of the vehicle increases faster as the vehicle speed increases. Since the change rate is changed, if it can be determined based on the vehicle speed that sufficient safety can be ensured even if an abnormality of the shift-by-wire control device appears in the vehicle running, the driving force of the vehicle is quickly determined according to the vehicle speed. The restriction on the vehicle can be relaxed, and the convenience of the driver can be improved while ensuring the safety in driving the vehicle.

  According to the vehicle shift-by-wire control device of the invention according to claim 4, the driving force at the time of the driving force limit control is a predetermined vehicle driving force set as low as possible so that the vehicle can travel. It is possible to make the vehicle travelable while ensuring safety in travel.

  When either one of the first route and the second route is normal and the other communication route itself is abnormal, the abnormality detection unit detects an abnormality of the shift-by-wire control device. In spite of the absence, the abnormality detection result may be obtained only through the other communication path. In this regard, according to the shift-by-wire control device for a vehicle of the invention according to claim 5, (a) when the second control unit obtains the abnormality detection result via the other communication path, A power shut-off means for shutting off the power transmission path prior to execution of the driving force limit control by the driving force limiting means, and (b) the driving force limit means outputs the abnormality detection result via the one communication path. If the abnormality detection result obtained through the other communication path without being obtained continues for a predetermined time, the power cut-off means is stopped from cutting off the power transmission path, and the driving force limit control is performed. Execute. Therefore, based on the fact that the abnormality detection result has not been obtained continuously through the one communication path, it can be determined that the abnormality detection means has not detected the abnormality, and until the determination can be made, By blocking the power transmission path, sufficient vehicle safety can be ensured.

  Here, preferably, the predetermined driving force limit time in claim 1 is provided to allow the driver to recognize that the driving force of the vehicle is limited for the purpose of ensuring safety in vehicle travel. It is a grace time.

  Preferably, the predetermined change rate in claim 2 is a time change rate of the driving force of the vehicle set in advance so as to achieve both safety ensuring in vehicle driving and improvement in driver convenience. is there.

  Preferably, the predetermined time in claim 5 is a time for determining that the abnormality detection means has not detected an abnormality of the shift-by-wire control device. If the abnormality detection result is not obtained continuously over a predetermined time through a communication path that does not transmit the detection result, the abnormality detection means can determine that the abnormality is not detected. It's time.

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

  FIG. 1 is a skeleton diagram of a laterally-mounted vehicle power transmission device 8 such as an FF (front engine / front drive) vehicle. In FIG. 1, a vehicle power transmission device 8 includes a torque converter 12 that is a fluid coupling and an automatic transmission 14 connected to the torque converter 12. The torque converter 12 is a gasoline engine or a diesel engine. It is connected with the engine 10 as a driving power source for driving | running | working (prime mover) comprised by internal combustion engines, such as. With such a configuration, the output of the engine 10 is transmitted to a driving wheel (front wheel) from a differential gear device (not shown) via the torque converter 12 and the automatic transmission 14.

  The automatic transmission 14 constitutes a part of a power transmission path from the engine 10 to the drive wheels. The automatic transmission 14 includes a first transmission unit 22 mainly composed of a single pinion type first planetary gear unit 20, a single pinion type second planetary gear unit 26, and a double pinion type third planetary unit. A second transmission unit 30 mainly composed of the gear device 28 is provided on the coaxial line, and the rotation of the input shaft 32 is shifted and output from the output gear 34. The input shaft 32 corresponds to the input member, and in this embodiment is the turbine shaft of the torque converter 12, and the output gear 34 corresponds to the output member, and rotates the left and right drive wheels via the differential gear device. To drive. The automatic transmission 14 is substantially symmetrical with respect to the center line, and the lower half of the center line is omitted in FIG.

  The first planetary gear unit 20 constituting the first transmission unit 22 includes three rotation elements, that is, a sun gear S1, a carrier CA1, and a ring gear R1, and the sun gear S1 is connected to the input shaft 32 to be rotationally driven. At the same time, the ring gear R1 is fixed to the case 36 through the third brake B3 so as not to rotate, whereby the carrier CA1 as an intermediate output member is rotated at a reduced speed with respect to the input shaft 32. Further, the second planetary gear device 26 and the third planetary gear device 28 constituting the second transmission unit 30 are partially connected to each other to constitute four rotating elements RM1 to RM4. Specifically, the first rotating element RM1 is configured by the sun gear S3 of the third planetary gear device 28, and the ring gear R2 of the second planetary gear device 26 and the ring gear R3 of the third planetary gear device 28 are connected to each other to perform the second rotation. The element RM2 is configured, and the carrier CA2 of the second planetary gear unit 26 and the carrier CA3 of the third planetary gear unit 28 are coupled to each other to configure a third rotating element RM3. A four-rotation element RM4 is configured. In the second planetary gear device 26 and the third planetary gear device 28, the carriers CA2 and CA3 are constituted by a common member, the ring gears R2 and R3 are constituted by a common member, and the second The pinion gear of the planetary gear device 26 is a Ravigneaux type planetary gear train that also serves as the second pinion gear of the third planetary gear device 28.

  The first rotating element RM1 (sun gear S3) is selectively connected to the case 36 by the first brake B1 and stopped rotating, and the second rotating element RM2 (ring gears R2, R3) is selectively selected by the second brake B2. The fourth rotation element RM4 (sun gear S2) is selectively connected to the input shaft 32 via the first clutch C1, and the second rotation element RM2 (ring gears R2, R3) is connected to the case 36 and stopped. Is selectively connected to the input shaft 32 via the second clutch C2, and the first rotating element RM1 (sun gear S3) is integrally connected to the carrier CA1 of the first planetary gear unit 20, and the third rotating element RM3. (Carriers CA2, CA3) are integrally connected to the output gear 34 to output rotation.

  The clutches C1, C2 and the brakes B1, B2, B3 (hereinafter simply referred to as “clutch C” and “brake B” unless otherwise specified) are hydraulic pressures controlled by a hydraulic actuator such as a multi-plate clutch or brake. 3 is a frictional engagement device (hydraulic frictional engagement element), and is controlled to be released by the hydraulic control circuit 40 shown in FIG. 3, so that the shift lever 66 (see FIG. 3) is operated in accordance with the shift operation position. As shown in FIG. 2, each of the six forward gears and one reverse gear (ie, each gear) is established. In FIG. 2, “1st” to “6th” mean forward first gear to sixth gear, and “Rev” means reverse gear, and the automatic transmission 14 corresponding to each gear. Of the first planetary gear device 20, the second planetary gear device 26, and the third planetary gear device 28, the gear ratios ρ1, ρ2, and the gear ratio γ (= input shaft rotational speed Nin / output shaft rotational speed Nout) of It is determined appropriately by ρ3. “◯” in FIG. 2 means engagement, and a blank means release. The input shaft rotational speed Nin is the rotational speed of the input shaft 32, and the output shaft rotational speed Nout is the rotational speed of the output gear 34.

  FIG. 3 is a circuit diagram relating to the linear solenoid valves SL1 to SL4 and the like for controlling the operation of the hydraulic actuators of the clutch C and the brake B, and is a circuit diagram showing the main part of the hydraulic control circuit 40.

  In FIG. 3, D range pressures (forward range pressure, forward hydraulic pressure) PD output from the hydraulic pressure supply device 52 are respectively applied to the hydraulic actuators (hydraulic cylinders) 42, 44, 46 of the clutches C1, C2 and the brake B1. The pressure is regulated and supplied by the linear solenoid valves SL1, SL2, and SL3, and the line hydraulic pressure PL1 output from the hydraulic pressure supply device 52 is regulated and supplied to the hydraulic actuator 50 of the brake B3 by the linear solenoid valve SL4. It has become. Note that either the output hydraulic pressure of the second brake control valve 54 or the reverse pressure (reverse range pressure, reverse hydraulic pressure) PR is supplied to the hydraulic actuator 48 of the brake B2 via the shuttle valve 56. .

The hydraulic pressure supply device 52 adjusts the line hydraulic pressure PL1 (first line hydraulic pressure PL1) using the hydraulic pressure generated from the mechanical oil pump 58 that is rotationally driven by the engine 10 as a source pressure, for example, a relief type primary regulator valve (first The pressure of the line oil pressure PL2 (second pressure oil pressure PL2, secondary pressure PL2) is adjusted using the hydraulic pressure discharged from the first pressure regulating valve 60 for adjusting the pressure of the line pressure PL1 by the first pressure regulating valve 60. secondary regulator valve (second pressure regulating valve) 62 for pressurizing, line pressure PL1 corresponding to the engine load or the like represented by the opening theta _TH of accelerator opening Acc or the electronic throttle valve, a first adjustment in order to be pressure PL2 two tone supplying a signal pressure _{P SLT} to valve 60 and the second pressure regulating valve 62 linear solenoid valve SLT, a line oil pressure PL1 The SBW actuator 68 (see FIG. 7) is actuated in accordance with the operation of the modulator valve 64 that regulates the modulator hydraulic pressure PM to a constant value as a pressure and the shift lever 66 that is electrically connected via a wire (electric wire). When the shift lever 66 is operated to the “D” position or the “B” position, the line hydraulic pressure PL1 input by switching the path is output as the D range pressure PD, or the reverse pressure when the shift lever 66 is operated to the “R” position. A manual valve 70 or the like that outputs as PR is provided, and line hydraulic pressures PL1 and PL2, modulator hydraulic pressure PM, D range pressure PD, and reverse pressure PR are supplied.

  The linear solenoid valves SL1 to SL4 and SLT have basically the same configuration, and are excited and de-energized independently by the electronic control unit 104, and the hydraulic pressures of the hydraulic actuators 42, 44, 46, and 50 are independently adjusted. The pressure is controlled to control the engagement pressures of the clutches C1, C2 and the brakes B1, B3. In the automatic transmission 14, for example, as shown in the engagement operation table of FIG. 2, each gear stage is established by engaging a predetermined engagement device. In the shift control of the automatic transmission 14, for example, so-called clutch-to-clutch shift is performed in which release and engagement of the clutch C and the brake B involved in the shift are controlled simultaneously. For example, as shown in the engagement operation table of FIG. 2, in the upshift from the second speed to the third speed, the brake B1 is released and the brake B3 is engaged, and the release transient hydraulic pressure of the brake B1 is suppressed so as to suppress the shift shock. And the engagement transient hydraulic pressure of the brake B3 are appropriately controlled. Thus, since the engagement devices (clutch C, brake B) of the automatic transmission 14 are controlled by the linear solenoid valves SL1 to SL4, the responsiveness of the operation of the engagement device is improved. Alternatively, the hydraulic circuit for the engagement / release operation of the engagement device is simplified.

  The shift lever 66 is disposed, for example, in the vicinity of the driver's seat, and as shown in FIG. 4, there are three “R” position, “N” position, “D” position arranged in the longitudinal direction of the vehicle, and The H-shaped pattern is operated to the “+” position, “B” position, and “−” position for manual operation arranged in parallel. In the present embodiment, a P operation button 72 for operating the P position and locking the parking is provided as a separate switch.

  The “R” position is a reverse travel position (position) for reversing the rotation direction of the output gear 34 of the automatic transmission 14, and the “N” position interrupts power transmission in the automatic transmission 14. This is a neutral position for setting the neutral state. The “D” position is a shift range (D range) that allows the automatic transmission 14 to change gears, and all of the first gear stage “1st” to the sixth gear stage “6th”. Is a forward travel position that executes automatic shift control using a forward gear position, and the “B” position is a plurality of types of shift ranges that limit the change range of the gear stage, that is, a plurality of types of shifts with different gear stages on the high vehicle speed side. This is a forward travel position that allows manual shifting by switching the range. The “P” position selected by the operation of the P operation button 72 releases the power transmission path in the automatic transmission 14, that is, a neutral state (neutral state) in which the power transmission in the automatic transmission 14 is interrupted and is not illustrated. This is a parking position for mechanically preventing (parking lock) the rotation of the output gear 34 by the parking lock mechanism.

  At the “B” position, the “+” position for shifting the shift range up each time the shift lever 66 is operated, and the “−” for shifting the shift range down every time the shift lever 66 is operated. Position is provided. For example, in the “B” position, any of the “6” range to the “L” range is changed according to the operation of the shift lever 66 to the “+” position or the “−” position. The “L” range at the “B” position is also an engine brake range for obtaining a further engine brake effect by engaging the second brake B2 at the first gear stage “1st”.

  The “D” position is an automatic transmission mode that is a control mode in which automatic transmission control is performed in a range of, for example, a first gear to a sixth gear as shown in FIG. The “B” position is a shift position to be selected. In the “B” position, automatic shift control is executed in a range not exceeding the maximum speed gear of each shift range of the automatic transmission 14 and the shift changed by manual operation of the shift lever 66 is performed. It is also a shift position for selecting a manual shift mode that is a control mode in which manual shift control is executed based on the range (that is, the highest speed gear stage).

  Returning to FIG. 3, the power transmission path of the automatic transmission 14 is suddenly interrupted before the hydraulic actuator 42 of the clutch C <b> 1, that is, between the linear solenoid valve SL <b> 1 and the hydraulic actuator 42 due to some failure during traveling ( A fail-safe valve 74 is provided to prevent the torque from being lost. The fail-safe valve 74 supplies the D range pressure PD to the hydraulic actuator 42 when, for example, the hydraulic pressure cannot be supplied to the hydraulic actuator 42 due to a failure of the linear solenoid valve SL1, for example. Prevents power transmission interruption (torque loss). Note that if the power transmission path of the automatic transmission 14 is interrupted during traveling, the vehicle becomes unstable and the operability of the vehicle may deteriorate, so the fail-safe valve 74 is provided.

FIG. 5 is an enlarged circuit diagram showing the vicinity of the fail-safe valve 74. The fail safe valve 74 includes an input port 76 to which the engagement hydraulic pressure PC1 is supplied from the linear solenoid valve SL1, an input port 78 to which the D range pressure PD is supplied, and an output port 80 connected to the hydraulic actuator 42 of the clutch C1. And a spool (not shown). The spool includes an engagement hydraulic pressure PC1 of the clutch C1 output from the linear solenoid valve SL1, an engagement hydraulic pressure PC2 of the clutch C2 output from the linear solenoid valve SL2, and a spring 82. Spring force FS1 is applied in one direction, the brake B1 engagement hydraulic pressure PB1 output from the linear solenoid valve SL3, the brake B3 engagement hydraulic pressure PB3 output from the linear solenoid valve SL4, and the linear solenoid valve. SLT or The signal pressure P _SLT or its associated pressure output is adapted to be allowed to act in the other direction opposite to the above one direction.

  In the automatic transmission 14 of the present embodiment, at the time of forward traveling, as shown in FIG. 2, at least one of the engagement hydraulic pressure PC1 of the clutch C1 and the engagement hydraulic pressure PC2 of the clutch C2 is always output. The brake B1 and the brake B3 are friction engagement elements that are paired with the clutch C1 and the clutch C2, and one of them is engaged in the gear stage (gear stage) excluding the first gear stage and the fourth gear stage. Combined. Note that the brake B2 that is engaged in the first gear is merely engaged when the first gear that applies the engine brake is established, and is therefore used less frequently. ing.

When the engagement hydraulic pressure PC1 and / or the engagement hydraulic pressure PC2 is input to the fail-safe valve 74 during forward travel, the engagement hydraulic pressure PB1, the engagement hydraulic pressure PC2 and the engagement hydraulic pressure PC2 are applied by the urging force of the engagement hydraulic pressure and the spring force FS1. and Ko' the urging force by the relevant pressure if hydraulic PB3, and the signal pressure P _SLT, the spool is moved in one direction side. As a result, the input port 76 and the output port 80 are communicated with each other, and the engagement hydraulic pressure PC 1 is supplied to the hydraulic actuator 42.

On the other hand, for example, if the engagement hydraulic pressure PC1 is not supplied due to a failure of the linear solenoid valve SL1, the engagement hydraulic pressure PC1 and the engagement hydraulic pressure PC2 are not supplied to the failsafe valve 74 in the first to third shift speeds. engaging hydraulic pressure PB1, it is moved in the other direction opposite to the spool the one direction side by the biasing force of the associated pressure of the engagement pressure PB3, and the signal pressure P _SLT. As a result, the input port 78 and the output port 80 are communicated, and the D range pressure PD is supplied to the hydraulic actuator 42 of the clutch C1. That is, even if the linear solenoid valve SL1 breaks down and the engagement hydraulic pressure PC1 is no longer supplied to the hydraulic actuator 42, the D range pressure PD is supplied to the hydraulic actuator 42, and sudden torque loss during traveling is avoided.

FIG. 6 is an enlarged circuit diagram showing the vicinity of the second brake control valve 54. The second brake control valve 54 includes an input port 84 to which the D range pressure PD is input, a drain port 86, an output port 88 connected to the hydraulic actuator 48 of the brake B2 through the shuttle valve 56, and a spool (not shown). The spool is acted in one direction by a control pressure _PSLU , which will be described later, and is acted in the other direction opposite to the one direction by the engagement hydraulic pressure PB2 of the brake B2 and the spring force FS2 of the spring 90. It is like that.

Normally, the drain port 86 and the output port 88 are brought into communication with each other by urging the spool in the other direction by the spring force FS2 of the spring 90, so that the hydraulic pressure is applied to the hydraulic actuator 48 from the output port 88. Is not supplied. Here, when the control pressure _PSLU is supplied to the second brake control valve 54, the spool is moved in one direction against the urging force of the spring 90, and the input port to which the D range pressure PD is supplied. 84 and the output port 88 are in communication with each other, and the engagement hydraulic pressure PB <b> 2 is supplied to the hydraulic actuator 48 via the shuttle valve 56.

Here, the control pressure _PSLU is output from a linear solenoid valve SLU (not shown) and is supplied through a relay valve 92 disposed on the front side of the second brake control valve 54. The relay valve 92 selectively switches the supply destination of the control pressure _PSLU to either the second brake control valve 54 or the lockup control valve 98 for controlling the lockup clutch L / C of the torque converter 12. a switching valve is switched supply destination of the control pressure P _SLU by switching pressure PSL output from the switching solenoid valve SL (not shown). Specifically, the relay valve 92 includes an input port 94 to which the control pressure _PSLU is supplied, an output port 96 connected to the second brake control valve 54, and an output port 100 connected to the lockup control valve 98. And a spool (not shown) that is acted on in one direction by the switching pressure PSL, and is acted on in the other direction opposite to the one direction by the spring force FS3 of the spring 102. Yes.

Since the spring 102 biases the spool in the other direction, the input port 94 and the output port 96 are communicated with each other. As a result, the control pressure P _SLU is supplied to the second brake control valve 54, and the D range pressure PD is adjusted by the control pressure P _SLU and supplied to the hydraulic actuator 48. On the other hand, when the switching pressure PSL is output from the switching solenoid valve SL, the spool of the relay valve 92 is moved in one direction against the spring force FS3 of the spring 102, and the supply destination of the control pressure _PSLU is locked up. The lockup control valve 98 for controlling the clutch engagement pressure is switched.

  FIG. 7 shows the electric power transmission device 8 for vehicles in which the shift position of the manual valve 70 is electrically changed according to the shift range change instruction by the driver, specifically, according to the operation of the shift lever 66 by the driver. FIG. 2 is a block diagram illustrating a control system of a shift-by-wire control device 103 (shift-by-wire system 103) that executes shift control of the automatic transmission 14 and shows a main part of the configuration of the shift-by-wire control device 103. It is.

  In FIG. 7, the shift-by-wire control device 103 includes a shift operation device 65 having a shift lever 66, a shift position sensor 67, and a P operation button 72, an SBW actuator 68, a shift position sensor 118, an electronic control device 104, and the like. I have. When the shift position of the shift lever 66 is switched by the driver, an electric signal corresponding to the shift position is input to the electronic control unit 104 (SBW-ECU 112) via the shift position sensor 67. Then, the SBW actuator 68 is controlled by the electronic control unit 104 (SBW-ECU 112), and the switching shaft 106 is rotated around the axis, whereby the spool 110 of the manual valve 70 is mechanically aligned in a straight line direction via the lever 108. And the oil passages are switched by positioning at four shift positions “P”, “R”, “N”, and “D”.

  As shown in FIG. 7, the electronic control unit 104 serves as a SBW-ECU 112 that functions as a first control unit that outputs a control signal related to vehicle travel, and a second control unit that executes control related to vehicle travel based on the control signal. A functioning ECT-ECU 114, an EFI-ECU 116 functioning mainly as a third control unit that executes control related to fuel supply to the engine 10, and a control signal transmitted between the SBW-ECU 112 and the ECT-ECU 114 are parallel to each other. A communication path 134 (see FIG. 8) for connecting the ECUs 112, 114, and 116 to each other, including a first path 136 and a second path 138. For example, the SBW-ECU 112 detects the shift position of the shift lever 66, operates the SBW actuator 68 based on the shift position, and outputs the control signal exemplified by the detected shift position information to the ECT-ECU 114. The ECT-ECU 114 executes, for example, control of the engine 10 and shift control of the automatic transmission 14 as control related to the vehicle travel. Further, the EFI-ECU 116 controls the basic injection time calculated according to the state of the engine 10 to correct fuel injection by correcting the basic injection time by the signal of each sensor.

The SBW-ECU 112 and the ECT-ECU 114 are connected by a plurality of independent wires (electric wires). For example, when the SBW actuator 68 fails, the SBW abnormality signal S _FL and the shift position of the shift lever 66 are “R”. The above control signals such as the R signal indicating that the switch has been switched to the range, the NSW signal indicating the shift range of the automatic transmission 14, and the D signal indicating that the shift position of the shift lever 66 has been switched to the “D” range. Communication is performed via independent wires. Further, the SBW-ECU 112 and the ECT-ECU 114 can communicate information via the EFI-ECU 116. Here, between the SBW-ECU 112 and the EFI-ECU 116, and between the ECT-ECU 114 and the EFI-ECU 116, a multiplex communication system capable of performing a plurality of information communication using a single communication line, so-called CAN communication is adopted. Yes. As described above, the information communication is performed between the SBW-ECU 112 and the ECT-ECU 114 via the first route 136 and the second route 138 which are two communication routes 134 provided in parallel. The improvement of the reliability of information communication is achieved. In this embodiment, as shown in FIG. 7, a communication path 134 that directly connects the SBW-ECU 112 and the ECT-ECU 114 without using the EFI-ECU 116 is represented as a first path 136, which is different from the first path 136. The communication path 134 that connects the SBW-ECU 112 and the ECT-ECU 114 via the EFI-ECU 116 is represented as a second path 138.

FIG. 8 is a functional block diagram for explaining a main part of the control function by the electronic control unit 104. An abnormality (fail, failure) may occur in the shift-by-wire control device 103 such as the failure of the SBW actuator 68 described above, and an SBW-ECU (first control) that constitutes a part of the electronic control device 104 in preparation for such a case. Part) 112 is provided with an abnormality detecting means 132 for detecting an abnormality of the shift-by-wire control device 103. The abnormality of the shift-by-wire control device 103 is, for example, from an electric signal (target shift position signal) corresponding to the shift position output from the shift position sensor 67 of the shift lever 66 and a shift position sensor 118 provided in the SBW actuator 68. This is a case where the shift positions based on the electrical signal (actual shift position signal) corresponding to the output shift position do not coincide with each other, that is, when the shift operating device 65 and / or the SBW actuator 68 fails. As another example, when at least one of the shift position sensors 67 and 118 functioning as a shift position detecting device malfunctions or when the SBW-ECU 112 has a self-diagnosis function, the SBW-ECU 112 itself has failed. This case is also included in the abnormality of the shift-by-wire control device 103 detected by the abnormality detection means 132. In short, the abnormality of the shift-by-wire control device 103 detected by the abnormality detection means 132 is when the device for determining the shift range has failed (state). When the abnormality detection unit 132 detects such an abnormality of the shift-by-wire control device 103, the abnormality detection unit 132 outputs a control signal indicating an abnormality detection result indicating the abnormality, that is, an SBW abnormality signal _SFL to the ECT-ECU 114. Then, the SBW abnormal signal _{S FL} via the respective first path 136 constituting the communication path 134 between the ECT-ECU 114 and SBW-ECU 112 and the second path 138 is transmitted to the ECT-ECU 114 The When it is desired to particularly distinguish the communication path 134 for SBW abnormal signal _{S FL} is the SBW abnormal signal _{S FL} transmitted to the ECT-ECU 114 through the first path 136 represents the "SBW abnormal signal _{S1 FL"} the SBW abnormal signal _{S FL} transmitted to the ECT-ECU 114 via the second path 138 is represented as "SBW abnormal signal _{S2 FL".}

Further, the abnormality detecting means 132, if no abnormality is detected in the shift-by-wire control unit 103 does not output the SBW abnormal signal _{S FL} to ECT-ECU 114. That is, the abnormality detection unit 132 detects the normal state of the shift-by-wire control device 103 when the shift positions indicated by the signals of the shift position sensors 67 and 118 coincide with each other and does not detect any other abnormality. If it is, the outputs a signal indicating the normal shift position or the like to be communicated to the normal state without outputting the SBW abnormal signal S _FL, with this, a normal detection result indicating the normal state of the shift-by-wire control device 103 Is output to the ECT-ECU 114. The abnormality detection result and the normal detection result of the abnormality detection unit 132 as described above are transmitted to the ECT-ECU 114 (power transmission permission unit 146) through the first path 136 and the second path 138 provided in parallel. Is done.

  An ECT-ECU (second control unit) 114 constituting a part of the electronic control unit 104 includes a power transmission permission means (permission means) 146 including a first reception determination means 142 and a second reception determination means 144, an engine. A power shut-off means 148 for shutting off the power transmission path from 10 to the drive wheel, and a driving force limiting means 154 for limiting the driving force of the vehicle after the power shut-off means 148 stops shutting off the power transmission path. And a driving force recovery means 156 for relaxing the restriction after the driving force limiting means 154 limits the driving force of the vehicle and recovering the driving force of the vehicle.

The first reception determination unit 142 receives a signal from the SBW-ECU 112 via the first path 136. When the first reception determination unit 142 receives the SBW abnormality signal S1 _FL via the first path 136, the first reception determination unit 142 determines that the abnormality detection result related to the shift-by-wire control device 103 has been obtained. On the other hand, when the SBW abnormality signal S1 _FL is not received, it is determined that the abnormality detection result is not obtained, in other words, the normal detection result regarding the shift-by-wire control device 103 is obtained.

The second reception determination unit 144 receives a signal from the SBW-ECU 112 via the second path 138. When the second reception determination unit 144 receives the SBW abnormality signal S2 _FL via the second path 138, the second reception determination unit 144 determines that the abnormality detection result related to the shift-by-wire control device 103 has been obtained. On the other hand, when the SBW abnormality signal S2 _FL is not received, it is determined that the abnormality detection result is not obtained, in other words, the normal detection result regarding the shift-by-wire control device 103 is obtained.

Further, when the second reception determination unit 144 determines that the abnormality detection result has been obtained, the first reception determination unit 142 determines whether the normal detection result has been obtained after the determination. If you continue normal state settling time Time_nf (predetermined time Time_nf) of performing normal state confirmation decision X _NF indicating that. On the other hand, when the first reception determination unit 142 determines that the abnormality detection result has been obtained, the second reception determination unit 144 determines whether the normal detection result has been obtained after the determination. If you continue normal state settling time Time_nf (predetermined time Time_nf) of performing normal state confirmation decision X _NF indicating that.

In short, the second reception determination unit 144 determines that the abnormality detection result (SBW abnormality signal S2 _FL ) has been obtained, and the first reception determination unit 142 determines that the normal detection result has been obtained. it is the case of the normal state settling time Time_nf (predetermined time Time_nf) continues, first reception determination unit 142 performs a normal state confirmation decision X _NF. On the other hand, the first reception determination unit 142 determines that the abnormality detection result (SBW abnormality signal S1 _FL ) has been obtained, and the second reception determination unit 144 determines that the normal detection result has been obtained. it is the case of the normal state settling time Time_nf (predetermined time Time_nf) continuing the second reception determination unit 144 performs a normal state confirmation decision X _NF. Further, after determining that at least one of the first reception determination unit 142 and the second reception determination unit 144 has obtained the abnormality detection result (SBW abnormality signal S _FL ), the SBW abnormality signal S for some reason. The normal state determination time time_nf (predetermined time time_nf) may be determined that both the first reception determination unit 142 and the second reception determination unit 144 obtain the normal detection result because the _FL is not received. In the case of continuing, both the first reception determination unit 142 and the second reception determination unit 144 perform the normal state determination determination _XNF . Note that the normal state confirmation time time_nf, when that time abnormality detection unit 132 if continuing to SBW abnormal signal _{S FL} is received over time_nf is not outputted to the SBW abnormal signal _{S FL} to ECT-ECU 114 This is an experimentally set time that can be determined in advance. In order to distinguish the normal state determination determination _XNF from the first reception determination unit 142 and the second reception determination unit 144, the first reception determination unit 142 is referred to as “normal state determination determination X1. _NF ”and the second reception determination unit 144 is expressed as“ normal state determination determination X2 _NF ”. If no distinction is made between them, it is expressed as “normal state determination determination X _NF ” as it is.

Power interrupting means 148, when the ECT-ECU 114 receives the SBW abnormal signal _{S FL} via the first path 136 and / or second path 138, i.e., first reception determination unit 142 and / or the second reception determination means When 144 determines that the abnormality detection result has been obtained, power cutoff control is executed to shut off the power transmission path from the engine 10 to the drive wheels. In the power cut-off control, if the driving force of the vehicle is not generated, there is no particular limitation on the achievement method. Therefore, the engine 10 may be stopped, but in this embodiment, the power transmission path in the automatic transmission 14 is cut off. Is done. Here, when the ECT-ECU 114 does not obtain the abnormality detection result (SBW abnormality signal S _FL ) via one of the first route 136 and the second route 138 but obtains the abnormality detection result via the other. In this case, the driving force limiting means 154 may execute the driving force limiting control described later. In this case, prior to the driving force limiting means 154 executing the driving force limiting control, the power shut-off means 148 Execute power shut-off control. In other words, even if one of the first reception determination unit 142 and the second reception determination unit 144 has made a determination that the normal detection result has been obtained, in other words, the one has made a normal state determination determination _XNF . If it is determined that the other side has obtained the abnormality detection result (SBW abnormality signal S _FL ), the power shut-off means 148 is preceded if the driving force limiting control is executed. Executes the power shut-off control, and if the driving force limiting control is not executed, the power shut-off means 148 executes the power shut-off control regardless of this. The driving force of the vehicle is a thrust force that moves the vehicle forward or backward, and has a one-to-one correspondence with driving wheel torque that rotates the driving wheel.

  In the power cut-off control, the power cut-off means 148 cuts off the power transmission path in the automatic transmission 14 as described above. Specifically, no forward shift stage or reverse shift stage is established. Both the frictional engagement element for forward movement and the frictional engagement element for backward movement in the automatic transmission 14 are released. That is, the neutral valve in which the solenoid valve of the hydraulic control circuit 40 is controlled so that the power transmission path in the automatic transmission 14 is cut off regardless of the shift position (manual valve position) of the manual valve 70 controlled by the SBW actuator 68. Pattern formation is performed. The hydraulic control circuit 40 of the automatic transmission 14 is configured so that the neutral pattern can be formed, that is, the power can be cut off regardless of the shift position of the manual valve 70. Hereinafter, taking the hydraulic control circuit 40 of the automatic transmission 14 as an example, the control operation of the power cut-off means 148 that cuts off the power transmission path in the automatic transmission 14 regardless of the shift position of the manual valve 70 will be described.

  First, a description will be given of control for releasing the frictional engagement element for the forward movement of the automatic transmission 14 and shutting off the power for the forward movement. In forward travel, as shown in FIG. 2, at least one of the clutch C1 and the clutch C2 is engaged. That is, the clutch C <b> 1 and the clutch C <b> 2 are friction engagement elements that are applied to advance the automatic transmission 14. As shown in FIG. 5, since the fail-safe valve 74 is provided between the linear solenoid valve SL1 and the hydraulic actuator 42, for example, even when the engagement hydraulic pressure PC1 is not engaged due to a failure of the linear solenoid valve SL1, The oil path is switched by the spool of the safe valve 74, and the D range pressure PD is supplied from the input port 78 to the hydraulic actuator 42. Therefore, the power cut-off means 148 reliably cuts off the power to advance the automatic transmission 14 by combining the following controls.

  First, by controlling the linear solenoid valve SL1, the engagement hydraulic pressure PC1 supplied to the hydraulic actuator 42 of the clutch C1 is controlled to zero. As a result, the spool of the fail safe valve 74 is moved, the input port 78 and the output port 80 are communicated, and the D range pressure PD may be supplied to the hydraulic actuator 42. The engagement hydraulic pressure PC2 of C2 is controlled to a maximum value, for example. As a result, the fail safe valve 74 is in a normal state, that is, the input port 76 connected to the linear solenoid valve SL1 and the output port 80 are in communication with each other, and no hydraulic pressure is supplied to the hydraulic actuator 42 of the clutch C1. The clutch C1 is released. Thereby, as shown in FIG. 2, the first to fourth shift speeds are not established.

  Further, by controlling the linear solenoid valve SL3, the engagement hydraulic pressure PB1 supplied to the hydraulic actuator 46 of the brake B1 is controlled to zero, and by controlling the linear solenoid valve SL4, the hydraulic actuator 50 of the brake B3 is controlled. The supplied engagement hydraulic pressure PB3 is controlled to zero. Here, the clutch C2 is engaged by controlling the engagement hydraulic pressure PC2 of the clutch C2 to the maximum value, but no hydraulic pressure is supplied to the hydraulic actuators 46, 50 of the brake B1 and the brake B3. The shift speed and the sixth shift speed are not established. Further, by controlling the linear solenoid valve SLT (or its associated pressure) to the minimum pressure, the fail-safe valve 74 can reliably prevent the communication between the input port 78 and the output port 80, that is, the oil pressure of the D range pressure PD. Supply to the actuator 42 is prevented.

  As a result, regardless of the shift position of the manual valve 70, the power to advance the automatic transmission 14 is cut off. Specifically, if the shift position of the manual valve 70 is the “D” position, the power to advance is cut off by the above control. In addition, since the D range pressure PD is not supplied at the “R” position, the D range pressure PD as the original pressure is not supplied to the linear solenoid valve SL1 and the linear solenoid valve SL2, and the clutch C1 and the clutch C2 are engaged. Since the hydraulic pressure is not supplied, the power to advance the automatic transmission 14 is cut off. In addition, since the D range pressure PD and the lever pressure PR are not supplied to the “N” and “P” positions, the power to advance is cut off.

Next, control for releasing the frictional engagement element for the reverse drive of the automatic transmission 14 and shutting off the power for the reverse drive will be described. In reverse travel, the brake B2 and the brake B3 are engaged as shown in FIG. 2, so that the power for the reverse travel is transmitted to the drive wheels. That is, the brake B2 and the brake B3 correspond to the frictional engagement elements for the reverse movement, and when either the brake B2 or the brake B3 is released, the power for the reverse movement of the automatic transmission 14 is cut off. Therefore, the power shut-off means 148 outputs a switching pressure PSL from the switching solenoid valve SL while (ON), and outputs the control pressure _{P SLU} from the solenoid valve SLU (ON). Further, the engagement hydraulic pressure PB3 of the hydraulic actuator 50 of the brake B3 is controlled to zero by controlling the linear solenoid valve SL4.

When controlled in this way, in FIG. 6, the input port 94 and the output port 100 of the relay valve 92 are communicated with each other by the switching pressure PSL of the switching solenoid valve SL, that is, the control pressure P _SLU of the linear solenoid valve _SLU is It is supplied to the lockup control valve 98. Accordingly, the control pressure P _SLU is not input to the second brake control valve 54. Since the control pressure _PSLU is not input to the second brake control valve 54, the spool is moved by the spring force FS2 of the spring 90, and the drain port 86 and the output port 88 are communicated, that is, the brake B2 The hydraulic actuator 48 and the drain port 86 are communicated with each other so that no hydraulic pressure is supplied to the hydraulic actuator 48. Thereby, the power to the reverse transmission of the automatic transmission 14 is interrupted.

  However, when the manual valve 70 is in the “R” position, the reverse pressure PR is supplied, so that the hydraulic pressure is supplied to the hydraulic actuator 48 of the brake B2. However, the power shut-off means 148 controls the engagement hydraulic pressure of the hydraulic actuator 50 of the brake B3 to zero, so that the third brake B3 is released, so that the power to the reverse transmission of the automatic transmission 14 is shut off. As a result, regardless of the shift position of the manual valve 70, the reverse drive power of the automatic transmission 14 is cut off. Specifically, if the shift position of the manual valve 70 is the “D” position, the power for forward movement is cut off by the above control, and if it is the “R” position, the reverse pressure PR is applied to the hydraulic actuator 48 of the brake B2. Although supplied, the brake B3 is released, so the power to the reverse is cut off. In addition, since the D range pressure PD and the lever pressure PR are not supplied to the “N” and “P” positions, the power to the reverse drive is cut off.

  In this way, the neutral pattern is formed by performing the above-described control of the power shut-off means 148, whereby the automatic transmission 14 moves forward and backward regardless of the shift position (manual valve position) of the manual valve 70. Is powered off.

As described above, the power cutoff unit 148 executes the neutral pattern formation, that is, the power cutoff control based on the determinations of the first reception determination unit 142 and the second reception determination unit 144, but the first reception determination unit 142. In addition to the determination by the second reception determination unit 144, the power cutoff control may be executed in consideration of the vehicle speed V. Referring to FIG. 8, first, the ECT-ECU 114 includes vehicle speed determination means 150. The vehicle speed determination means 150 is, for example, an output gear 34 that is an output member of the automatic transmission 14. The vehicle speed V is detected based on the rotational speed of the vehicle, and it is determined whether or not the vehicle speed V is equal to or lower than a predetermined vehicle speed V1. The predetermined vehicle speed V1 is obtained in advance through experiments or the like, and is set in a low vehicle speed range. Here, for example, at medium and high vehicle speeds, if the power transmission path in the automatic transmission 14 is interrupted, the torque transmitted to the drive wheels is lost (torque loss), so that the vehicle becomes unstable and the operability is improved. May be reduced. In the present embodiment, as described above, when the SBW abnormality signal _SFL is received, the power transmission path in the automatic transmission 14 is cut off by executing the power cut-off control. Therefore, when the vehicle speed V exceeds the predetermined vehicle speed V1, the power cutoff control is prohibited, thereby avoiding a decrease in operability of the vehicle due to torque loss. That is, the predetermined vehicle speed V1 is set to a low vehicle speed range in which the operability of the vehicle is not deteriorated even when the power shut-off control for shutting off the power transmission path between the engine 10 and the drive wheels is performed during traveling.

When the vehicle speed determination means 150 determines that the vehicle speed V is equal to or less than the predetermined vehicle speed V1, the power shut-off means 148 determines the first reception determination means 142 and the second reception determination means 144 as described above. Based on the above, the power cutoff control is executed. In other words, when the vehicle speed V exceeds the predetermined vehicle speed V1, the power cut-off means 148 does not depend on the determination of the first reception determination means 142 and the second reception determination means 144, that is, the SBW abnormality Regardless of whether the signal _SFL is received or not, the power cutoff control is not executed.

Thus, the power cut-off means 148 executes the power cut-off control as the fail-safe process, but after the start of the execution, the power cut-off control is stopped (interrupted) under a certain condition, and the vehicle can travel. May be switched to fail-safe processing. This is because the abnormality detecting means 132 despite not output to the SBW abnormal signal _{S FL} to ECT-ECU 114, anomaly of the first path 136 or second path 138 (fail, failure) by SBW abnormal signal _{S FL} This is because the same signal may be transmitted to the ECT-ECU 114, and in such a case, it is considered unnecessary to disable the vehicle traveling by the power cutoff control. Therefore, a description will be given below of control that is switched to fail-safe processing in which the power cutoff control is stopped and the vehicle can travel after the power cutoff control is executed.

In FIG. 8, the ECT-ECU 114 does not obtain the abnormality detection result (SBW abnormality signal S _FL ) of the abnormality detecting means 132 via one communication path 134 of the first path 136 and the second path 138. When the abnormality detection result is obtained via the path 134, that is, one of the first reception determination unit 142 and the second reception determination unit 144 determines that the normal detection result is obtained, but the other When it is determined that the abnormality detection result has been obtained, the power transmission permission unit 146 performs a fail-safe process capable of traveling the vehicle in which the output (power) from the engine 10 is transmitted to the drive wheels. Is given to the driving force limiting means 154, that is, it is allowed to execute driving force limiting control (to be described later) that can generate the driving force of the vehicle. To.

Here, as described above, when the ECT-ECU 114 receives the SBW abnormal signal _{S FL} via the first path 136 and / or second path 138, whether the driving force limiting control will be described later, it is executed Prior to this, the power shut-off means 148 executes the power shut-off control. Therefore, in detail in the present embodiment, the ECT-ECU 114 does not obtain the abnormality detection result (SBW abnormality signal S _FL ) via the one communication path 134 of the first path 136 and the second path 138 and the other path. When obtaining the abnormality detection result via the communication path 134 continues for a predetermined normal state determination time time_nf (predetermined time time_nf), that is, one of the first reception determination unit 142 and the second reception determination unit 144 is normal. When the state determination determination _XNF is performed, but the other is determining that the abnormality detection result has been obtained, the power transmission permission unit 146 gives the driving force limitation unit 154 the power transmission permission.

Then, when the power transmission permission is given from the power transmission permission means 146, the driving force limiting means 154 is a normal time driving force that is a driving force when the vehicle is normal in a state where the vehicle can generate the driving force. Driving force limiting control is performed to limit the driving force of the vehicle lower than F _NM . That is, if the power cutoff control is being executed, the vehicle is not in a state where it can generate a driving force. At that time, when the power transmission permission is given, the driving force limiting means 154 In 148, the power cut-off control is stopped, and the driving force limiting control is executed. In short, when the power cutoff control is executed and then the driving force limiting control is executed, the power cutoff control is executed until the normal state determination time time_nf elapses, and the normal state determination time time_nf is When the time has elapsed, the driving force limiting control is executed instead of the power cutoff control.

Note that the ECT-ECU 114 obtains the abnormality detection result (SBW abnormality signal S _FL ) from any of the communication paths 134 (the first path 136 and the second path 138) as the normal driving force F _NM. The driving force of the vehicle when there is no vehicle, for example, the driving force of the vehicle that the ECT-ECU 114 exerts when the vehicle is normal based on a predetermined driving force map with the accelerator opening Acc and the vehicle speed V as parameters. is there.

Further, in the driving force limiting control of the present embodiment, the driving force of the vehicle is a predetermined limiting driving force F _DP lower than the normal driving force F _NM , but is not limited to this. This limited driving force F _DP is an experimentally predetermined vehicle driving force (driving) for allowing the driver to recognize that the driving force of the vehicle is limited for the purpose of ensuring safety in vehicle traveling. Force limit value), which is preferably a predetermined vehicle driving force (driving force limit value) set as low as possible to enable vehicle travel. Since the normal at the driving force F _NM varies depending on the accelerator opening Acc, when the limiting drive force F _DP is normal when the driving force F during normal operation the driving force changes according to the change in the _NM F _NM It is desirable that the driving force value is obtained by multiplying the normal driving force F _NM by a predetermined ratio (positive fraction) smaller than 1, for example.

  Further, the driving force limiting means 154 may cause the brakes provided on the wheels to exert the vehicle braking force in order to limit the driving force of the vehicle in the driving force limiting control, or may be a part of the power transmission path. The clutch C or the brake B of the automatic transmission 14 that constitutes the engine may be slid. However, in this embodiment, the vehicle is driven by suppressing the engine output with respect to the accelerator opening Acc as compared with the normal time. Limit power low.

After the driving force limiting control is executed by the driving force limiting unit 154, the driving force recovery unit 156 reduces the driving force of the vehicle that has been reduced with _respect to the normal driving force _FNM by the driving force limiting control. The driving force recovery control is performed to increase the driving force F _NM during normal operation toward a predetermined target value less than or equal to the normal driving force F _NM . That is, the driving force recovery means 156 functions as a limit amount reducing means for reducing the limit amount (= F _NM −F _DP ) for the driving force of the vehicle in the driving force limit control. There is no particular limitation on how to increase the driving force of the vehicle in the driving force recovery control. For example, the driving force recovery control is performed at a predetermined driving force limit time time_df from the start of the driving force limit control. After the elapse of time, the vehicle driving force may be set to the intermediate driving force _FMD as the predetermined target value that is lower than the normal driving force _FNM and higher than the driving force during the driving force limiting control. . At this time, in the present embodiment, the driving force of the vehicle in the driving force limiting control is the limiting driving force F _DP , so the “driving force in the driving force limiting control” is the limiting driving force F _DP . is there. The driving force limit time time_df is an experimentally determined grace time for allowing the driver to recognize that the driving force is limited for the purpose of ensuring safety in vehicle travel. Further, the intermediate driving force _FMD is an experimentally predetermined vehicle driving force that can improve the convenience of the driver as compared with the execution of the driving force limiting control while ensuring safety in vehicle traveling. is there. Since the normal driving force F _NM and the limiting driving force F _DP both change according to the accelerator opening degree Acc and the like, the intermediate driving force F _MD is the normal driving force F _NM and the limiting driving force F _DP. For example, the intermediate driving force _FMD is smaller than 1 by the difference between the normal driving force _FNM and the limiting driving force _FDP. It is assumed that the driving force value obtained by multiplying the ratio (positive decimal number) is obtained by subtracting from the normal driving force _FNM .

Further, the driving force recovery means 156, for example, in the driving force recovery control, after the start of the driving force limit control, the normal driving force F _NM or a predetermined target value less than the normal driving force F _NM as time elapses (for example, the intermediate driving towards the force F _MD) at a predetermined rate of change R _P may increase the driving force of the vehicle. The change rate _RP is a time change rate of the driving force of the vehicle that is experimentally set in advance so as to achieve both safety in vehicle driving and improved convenience for the driver. Furthermore, the driving force recovery means 156, in the driving force recovery control may be changed to the change rate R _P as the driving force of the vehicle as the vehicle speed V is higher rises faster.

Incidentally, in the above case where the driving force power cutoff control is canceled limit control or drive power recovery control is executed, the previous SBW abnormal signal S _FL communication was not pathway 134 (first path 136 or second 2 pathway 138) through the ECT-ECU 114 is considered the case of receiving the SBW abnormal signal _{S FL.} Therefore, in the case where the power shutoff control (neutral pattern formation) is stopped when the ECT-ECU 114 and SBW abnormal signal _{S FL} via the first path 136 or second path 138 is receiving, the power cutoff After the control is stopped, the first reception determination unit 142 or the second reception determination unit 144 that has determined that the normal detection result that is the cause of the stop of the power cutoff control is obtained is the SBW abnormality signal S. When it is determined that the abnormality detection result is obtained by receiving _FL , the power transmission permission unit 146 cancels the power transmission permission and the driving force limit control or the driving force recovery control is executed. If it is, it is stopped and the power shut-off means 148 resumes the power shut-off control.

In order to determine whether or not the execution of the power cut-off control is to be resumed as described above, the determination that the normal detection result that is the cause of the stop of the power cut-off control is obtained is the first reception determination means. In other words, which of the first reception determination means 142 and the second reception determination means 144 is the abnormality detection result (SBW abnormality signal S _FL ). It is necessary to know whether the power shut-off control has been executed before the suspension by determining that the power has been obtained. Therefore, in addition to the above-described function, the power transmission permission unit 146, when the power cut-off control is executed by the power cut-off unit 148, the executed power cut-off control is performed according to which of the SBW abnormality signals S1 _FL and S2 _FL A history that can be known to be caused by the reception of is stored. That is, as described above, the power shut-off control may be stopped under certain conditions, but the history stored in the power transmission permission unit 146 may be determined if the power shut-off control is stopped. This is a history that shows which of the SBW abnormal signals S1 _FL and S2 _FL was received due to the received power shutoff control. More specifically, the power transmission permission unit 146 executes the power cutoff control because the first reception determination unit 142 determines that the abnormality detection result (SBW abnormality signal S1 _FL ) has been obtained. If it is, a history indicating that the power cut-off control (the neutral pattern formation) is executed based on the SBW abnormality signal S1 _FL is stored, that is, the neutral by the SBW abnormality signal S1 _FL is stored. The pattern formation history hst1_n is stored as “ON”. On the other hand, the power transmission permission unit 146 performs the power cutoff control when the second reception determination unit 144 determines that the abnormality detection result (SBW abnormality signal S2 _FL ) has been obtained. Stores a history indicating that the power cutoff control (the neutral pattern formation) is executed based on the SBW abnormality signal S2 _FL , that is, a neutral pattern formation history hst2_n based on the SBW abnormality signal S2 _FL. Is stored as “ON”. Then, the power transmission permission unit 146 outputs the neutral pattern formation histories hst1_n and hst2_n to the power cutoff unit 148, and the power cutoff unit 148 resumes the execution of the power cutoff control based on the neutral pattern formation histories hst1_n and hst2_n. Determine whether or not. The initial values of the neutral pattern formation histories hst1_n and hst2_n are both “OFF”.

If the first path 136 ECT-ECU 114 also via any of the second path 138 is not received continues the normal state settling time time_nf the SBW abnormal signal _{S FL,} i.e., a first reception determination unit 142 When both the second reception determination means 144 perform the normal state determination determination _XNF , the power shut-off means 148 stops the power shut-off control if it executes the power shut-off control, and the driving force limiting means 154 If the driving force limiting control is being executed, it is stopped, and the power recovery means 156 stops it if the driving force recovery control is being executed. As a result, the driving force of the vehicle returns to the normal driving force _FNM , that is, the fail-safe process is stopped. Further, in that case, the power transmission permission unit 146 sets both the neutral pattern formation histories hst1_n and hst2_n to “OFF”.

Here, preferably, in the case of stopping (interrupting) the power cutoff control (neutral pattern formation), the power cutoff means 148 is a case where the driving force of the vehicle returns to the normal driving force _FNM after the cancellation. Even if the driving force limiting control is executed, the power cutoff control is stopped after a predetermined return hold time time_rv has elapsed from the start of execution of the power cutoff control. In short, until the return hold time time_rv elapses, if the power shut-off control is being executed, it will not be stopped, and if it is stopped, it will be stopped after the return hold time time_rv has passed and the subsequent processing will be executed. Is done. The return hold time time_rv is a grace time set experimentally to prevent control hunting of the friction engagement element of the automatic transmission 14.

Preferably, the power shut-off means 148 stops the power shut-off control (neutral pattern formation) even if the driving force of the vehicle returns to the normal driving force F _NM after the stop. Even when the driving force limiting control is executed, the power cutoff control is stopped when a predetermined return permission condition is satisfied. The return permission condition is a condition for permitting the stop of the power shut-off control set experimentally for ensuring the safety of vehicle travel. Specifically, in the fail safe process, This is an experimentally set condition that permits the power transmission path of the power transmission path to be changed from a power transmission cut-off state in which power transmission is cut off to a power transmission capable state in which power transmission is possible. For example, the return permission condition is a low engine torque that does not cause the behavior of the vehicle to become unstable even if the power cutoff control is stopped, in other words, even if the engine output is transmitted to the drive wheels. It is established when the vehicle speed is low.

9 to 11, main control operation of the electronic control device 104, i.e., the power cutoff control as a fail-safe processing based on the SBW abnormal signal S _FL, driving force limiting control, executes the driving force recovery control It is a flowchart explaining a control operation, and is repeatedly executed with a very short cycle time of, for example, about several milliseconds to several tens of milliseconds.

As shown in FIG. 9, first, in the step (hereinafter, “step” is omitted) SA1 corresponding to the power transmission permission unit 146, is the neutral pattern formation history hst1_n based on the SBW abnormality signal S1 _FL “ON”? It is determined whether or not. When the determination of SA1 is affirmative, that is, when the neutral pattern formation history hst1_n is “ON”, the process proceeds to SA2. On the other hand, when the determination of SA1 is negative, the process proceeds to SA8. Note that the neutral pattern formation history hst1_n when the SBW abnormality signal S1 _FL is not received at all, that is, the initial value of the neutral pattern formation history hst1_n is “OFF”.

In SA2 corresponding to the second reception determination unit 144, the normal detection result of the abnormality detection unit 132 related to the shift-by-wire control device 103 is determined based on whether or not the SBW abnormality signal S2 _FL is received via the second path 138. It is determined whether it has been obtained. When the determination of SA2 is affirmative, i.e., if the ECT-ECU 114 does not receive the SBW abnormal signal _{S2 FL} proceeds to SA3. On the other hand, when the determination of SA2 is negative, the process proceeds to SA24 in FIG.

In SA3 corresponding to the second reception determination means 144, the ECT-ECU 114 performs the normal state determination time time_nf (predetermined time time_nf) from the time when the determination of SA2 is affirmed, and the ECT-ECU 114 performs the above-mentioned via the second path 138. It is determined whether or not a normal detection result has been obtained. If the ECT-ECU 114 does not receive the SBW abnormality signal S2 _FL via the second path 138 after the determination of SA2 is affirmed, the normal state determination time time_nf continues. If the determination continues for the normal state determination time time_nf, the determination of SA3 is affirmed. When the determination of SA3 is affirmative, i.e., if a positive determination of the SA2 continues normal state confirmation time time_nf, the normal state confirmation determination X2 _NF moves to SA4 performed. On the other hand, if the determination of SA3 is negative, the process proceeds to SA24 in FIG. When the determination of SA3 is affirmed, the power transmission permission unit 146 gives the power transmission permission to the driving force limiting unit 154.

In SA4 corresponding to the first reception determination unit 142, the normal detection result of the abnormality detection unit 132 related to the shift-by-wire control device 103 is determined based on whether or not the SBW abnormality signal S1 _FL is received via the first path 136. It is determined whether it has been obtained. When the determination of SA4 is affirmative, that is, when the ECT-ECU 114 has not received the SBW abnormality signal S1 _FL , the process proceeds to SA5. On the other hand, if the determination of SA4 is negative, the process proceeds to SA15 in FIG.

In SA5 corresponding to the first reception determination means 142, the ECT-ECU 114 continues to perform the normal state determination time time_nf (predetermined time time_nf) from the time when the determination of SA4 is affirmed via the first path 136. It is determined whether or not a normal detection result has been obtained. If the ECT-ECU 114 does not receive the SBW abnormality signal S1 _FL via the first path 136 after the determination of SA4 is affirmed, the normal state determination time time_nf continues. If the determination continues for the normal state determination time time_nf, the determination of SA5 is affirmed. If the determination of SA5 is affirmative, that is, if the affirmative determination of SA4 continues for the normal state determination time time_nf, the normal state determination determination X1 _NF is performed and the process proceeds to SA6. On the other hand, when the determination of SA5 is negative, the process proceeds to SA15 in FIG.

  In SA6 corresponding to the power cut-off means 148, it is determined whether or not the return hold time time_rv has elapsed from the start of execution of the power cut-off control executed in SA21 or SA25, which will be described later, that is, from the formation of the neutral pattern. Determined. If the determination of SA6 is affirmative, that is, if the return hold time time_rv has elapsed from the start of execution of the power cutoff control, the process proceeds to SA7. On the other hand, when the determination of SA6 is negative, the process proceeds to SA15 in FIG.

  In SA7 corresponding to the power shut-off means 148, it is determined whether or not the return permission condition is satisfied. If the determination of SA7 is affirmative, that is, if the return permission condition is satisfied, the process proceeds to SA16 in FIG. On the other hand, if the determination of SA7 is negative, the process proceeds to SA15 in FIG.

In SA8 corresponding to the power transmission permission unit 146, SBW abnormal signal _{S2 FL} neutral patterning history hst2_n by whether it is "ON" is determined. If the determination of SA8 is affirmative, that is, if the neutral pattern formation history hst2_n is “ON”, the process proceeds to SA9. On the other hand, if the determination of SA8 is negative, the process proceeds to SA19 in FIG. The initial value of the neutral pattern formation history hst2_n when the SBW abnormality signal S2 _FL is not received at all, that is, the neutral pattern formation history hst2_n is “OFF”.

In SA9 corresponding to the first reception determination unit 142, the same determination as in SA4 is performed. When the determination of SA9 is affirmative, that is, when the ECT-ECU 114 has not received the SBW abnormality signal S1 _FL , the process proceeds to SA10. On the other hand, when the determination of SA9 is negative, the process proceeds to SA20 in FIG.

In SA10 corresponding to the first reception determination unit 142, the ECT-ECU 114 performs the normal state determination time time_nf (predetermined time time_nf) from the time when the determination of SA9 is affirmed, and the ECT-ECU 114 passes the first route 136 through the first path 136. It is determined whether or not a normal detection result has been obtained. If the ECT-ECU 114 does not receive the SBW abnormality signal S1 _FL via the first path 136 after the determination of SA9 is affirmed, the normal state determination time time_nf continues. If the determination continues for the normal state determination time time_nf, the determination of SA10 is affirmed. If the determination of SA10 is affirmative, that is, if the affirmative determination of SA9 continues for the normal state determination time time_nf, the normal state determination determination X1 _NF is performed and the process proceeds to SA11. On the other hand, when the determination of SA10 is negative, the process proceeds to SA20 in FIG. When the determination of SA10 is affirmed, the power transmission permission unit 146 gives the power transmission permission to the driving force limiting unit 154.

In SA11 corresponding to the second reception determination means 144, the same determination as in SA2 is performed. When the determination of SA11 is affirmative, i.e., if the ECT-ECU 114 does not receive the SBW abnormal signal _{S2 FL} proceeds to SA12. On the other hand, when the determination of SA11 is negative, the process proceeds to SA18 in FIG.

In SA12 corresponding to the second reception determination unit 144, the normal state determination time time_nf (predetermined time time_nf) continues from the time when the determination of SA11 is affirmed, and the ECT-ECU 114 performs the above operation via the second path 138. It is determined whether or not a normal detection result has been obtained. If the ECT-ECU 114 does not receive the SBW abnormality signal S2 _FL via the second path 138 after the determination of SA11 is affirmed, the normal state determination time time_nf continues. If the determination continues for the normal state determination time time_nf, the determination of SA12 is affirmed. When the determination of SA12 is affirmative, i.e., if a positive determination of the SA11 continues normal state confirmation time time_nf passes to the normal state confirmation determination X2 _NF been conducted SA13. On the other hand, when the determination of SA12 is negative, the process proceeds to SA18 in FIG.

  In SA13 corresponding to the power shut-off means 148, the same determination as in SA6 is performed. If the determination of SA13 is affirmative, that is, if the return hold time time_rv has elapsed since the start of execution of the power shut-off control, the process proceeds to SA14. On the other hand, if the determination of SA13 is negative, the process proceeds to SA18 in FIG.

  In SA14 corresponding to the power shut-off means 148, the same determination as in SA7 is performed. If the determination of SA14 is affirmative, that is, if the return permission condition is satisfied, the process proceeds to SA16 in FIG. On the other hand, if the determination of SA14 is negative, the process proceeds to SA18 in FIG.

  In FIG. 10, in SA15 and SA18 corresponding to the power cut-off means 148, the drive force limiting means 154, and the drive force recovery means 156, if the power cut-off control is executed, it is stopped and the vehicle can run. The driving force limiting control as the fail-safe process and the subsequent driving force recovery control are executed. Specifically, the flowchart of FIG. 12 is executed.

  FIG. 12 is a flowchart for explaining a main part of the control operation in SA15 and SA18 of FIG. 10, that is, a control operation for executing fail-safe processing that enables vehicle travel.

  In SB1 corresponding to the power shut-off means 148, the neutral pattern formation is canceled. That is, if the power cut-off control is being executed, it is stopped, and if it is not already executed, it is continued. After SB1, the process proceeds to SB2.

  Preferably, if the power cut-off control is stopped in SB1, the power cut-off control is stopped after the return hold time time_rv has elapsed from the start of execution of the power cut-off control. Preferably, if the power cutoff control is stopped in SB1, the power cutoff control is stopped when the return permission condition is satisfied. Further, preferably, when the return permission condition is satisfied after the return hold time time_rv has elapsed from the start of execution of the power cut-off control, the power cut-off control is stopped.

In SB2 corresponding to the driving force limiting unit 154 and the driving force recovery unit 156, the driving force limitation control is executed, and then the driving force recovery control is executed. For example, the driving force of the vehicle is set to the limiting driving force F _DP by executing the driving force limiting control, and then the driving force recovery control is executed. Its driving force recovery control, for example, after a predetermined driving force limit time time_df elapsed from the start of the driving force limiting control may be a control for the driving force of the vehicle and the intermediate driving force F _MD. Further, after the start of the driving force limiting control, even control for increasing the driving force of the vehicle by the change rate R _P toward the normal when the driving force F _NM or a predetermined target value of less with time Good. In SB2, if the driving force limiting control or the driving force recovery control is being executed, it is continued.

Returning to FIG. 10, in SA16 corresponding to the power cut-off means 148, the drive force limit means 154, and the drive force recovery means 156, the power cut-off control (neutral pattern formation), the drive force limit control, or the drive force recovery control is performed. If it is running it will be aborted. That is, returning from the fail-safe process, the driving force of the vehicle returns to the normal driving force _FNM . In the automatic transmission 14, the shift control at the normal time (normal time) is executed, and the shift speed (gear speed) at the normal time (normal time) is formed.

In SA17 corresponding to the power transmission permission unit 146, both the neutral pattern formation histories hst1_n and hst2_n based on the SBW abnormality signals S1 _FL and S2 _FL are set to “OFF”.

In SA19 corresponding to the first reception determination unit 142 in FIG. 11, the abnormality detection unit 132 related to the shift-by-wire control device 103 determines whether or not the SBW abnormality signal S1 _FL is received via the first path 136. It is determined whether or not the abnormality detection result has been obtained. When the ECT-ECU 114 receives the SBW abnormality signal S1 _FL , a determination is made to affirm that the abnormality detection result has been obtained.
When the determination of SA19 is affirmative, that is, when the ECT-ECU 114 receives the SBW abnormality signal S1 _FL , the process proceeds to SA20. On the other hand, if the determination of SA19 is negative, the process proceeds to SA23.

  In SA20 corresponding to the vehicle speed determination means 150, it is determined whether or not the vehicle speed V is equal to or less than the predetermined vehicle speed V1. If the determination of SA20 is affirmative, that is, if the vehicle speed V is equal to or lower than the predetermined vehicle speed V1, the process proceeds to SA21. On the other hand, when the determination of SA20 is negative, this flowchart ends.

  In SA21 and SA25 corresponding to the power shut-off means 148, the power shut-off control is executed. Specifically, the neutral pattern is formed. Moreover, when the said power interruption control (neutral pattern formation) is already performed, it is continued. After SA21, the process proceeds to SA22, and after SA25, the process proceeds to SA26.

In SA22 corresponding to the power transmission permission unit 146, the neutral pattern formation history hst1_n based on the SBW abnormality signal S1 _FL is set to “ON”.

In SA23 corresponding to the first reception determination unit 142, the abnormality detection result of the abnormality detection unit 132 related to the shift-by-wire control device 103 is determined based on whether or not the SBW abnormality signal _S2FL is received via the second path 138. It is determined whether it has been obtained. When the ECT-ECU 114 receives the SBW abnormality signal S2 _FL , a determination is made to affirm that the abnormality detection result has been obtained. When the determination of SA23 is affirmative, i.e., if the ECT-ECU 114 receives the SBW abnormal signal _{S2 FL} proceeds to SA24. On the other hand, if the determination of SA23 is negative, this flowchart ends.

  In SA24 corresponding to the vehicle speed determination means 150, it is determined whether the vehicle speed V is equal to or lower than the predetermined vehicle speed V1 as in the case of SA20. If the determination of SA24 is affirmative, that is, if the vehicle speed V is equal to or lower than the predetermined vehicle speed V1, the process proceeds to SA25. On the other hand, if the determination of SA24 is negative, this flowchart ends.

In SA26 corresponding to the power transmission permission unit 146, a neutral pattern formation history hst2_n by SBW abnormal signal _{S2 FL} is set to "ON".

FIG. 13 is a time chart for explaining the control operation shown in the flowcharts of FIGS. 9 to 12. Specifically, the ECT-ECU 114 detects the SBW abnormality signal while the vehicle is traveling at the vehicle speed V equal to or lower than the predetermined vehicle speed V1. In the case where the state where the S1 _FL is received and the SBW abnormality signal S2 _FL is not received continues, the power cutoff control, the driving force limit control, and the driving force recovery control are sequentially executed as an example. It is a time chart for demonstrating the change of driving force. Normally, the normal driving force F _NM changes according to the accelerator opening Acc, but in FIG. 13, the normal driving force F _NM is constant for easy understanding. Is a schematic representation of changes in the driving force of the vehicle.

The time point t _A1 indicates a time point when the ECT-ECU 114 receives the SBW abnormality signal S1 _FL in a state where the ECT-ECU 114 does not receive the SBW abnormality signal S2 _FL . _Accordingly, the power cutoff control at SA21 determination of SA19 is affirmative Figure 11 _{t A1} point (neutral pattern formation) is performed. As a result, as shown in FIG. 13, at time t _A1 , the power transmission path in the automatic transmission 14 is in the power transmission cut-off state, and the driving force of the vehicle is zero.

At time t _A2 when a predetermined time time_nf has elapsed from time t _{A1, the} power cutoff control is stopped at SB1 in FIG. 12, and when the driving force of the vehicle is limited by the start of execution of the driving force restriction control at SB2 in FIG. The time point when the driving force F _DP is set is shown. The SB1 and SB2 are executed because the ECT-ECU 114 has not received the SBW abnormal signal S2 _FL since the normal state determination time time_nf (predetermined time time_nf) continues from the time point t _A1 . This is because the determination of SA3 is affirmed and the determination of SA4 in FIG. 9 is denied because the ECT-ECU 114 receives the SBW abnormality signal S1 _FL .

The time point t _{A3 in} FIG. 13 indicates a time point when the execution of the driving force recovery control is started after the driving force limiting control is completed in SB2 in FIG. In the driving force recovery control, for example, as indicated by the solid line between the time t _{A3 and the} time t _A4 , the driving force of the vehicle changes toward the normal driving force F _NM as time passes. _Raised at RP. Therefore, when the driving force of the vehicle changes as shown by the solid line in FIG. 13, it can be said that the time between the time t _{A2 and the} time t _A3 is “at the time of driving force limit control”. In FIG. 13, the driving force of the vehicle is maintained at the limited driving force F _DP between the time point t _{A2 and the} time point t _A3, but the driving force of the vehicle is thus limited for a certain period of time. It is not necessary to maintain at the _DP , and immediately after the driving force of the vehicle is set to the limiting driving force F _DP (driving force at the driving force limiting control) by executing the driving force limiting control, the driving force recovery control is performed immediately. The driving force of the vehicle may be increased by executing the above.

Here, a plurality of other control patterns of the driving force of the vehicle in the driving force recovery control can be considered. For example, in the driving force recovery control, as indicated by a broken line in FIG. 13, at the time point T _A3 ′ when the driving force limit time time_df has elapsed from the start of execution of the driving force limit control (time point t _A2 ), the driving force is and the intermediate driving force F _MD, then at SA16 of FIG. 10 until the return from the fail-safe processing, the driving force of the vehicle may be maintained at the intermediate driving force F _MD. Alternatively, without the driving force of the vehicle to return from the fail-safe process is maintained in the intermediate drive force F _MD, as shown by a chain line in FIG. 13, t _{A3 'from} time at finite time elapsed example t _A4 point The driving force of the vehicle may be returned to the normal driving force _FNM . Thus, when the driving force of the vehicle changes as shown by the broken line in FIG. 13, it can be said that the time between the time t _{A2 and the} time t _A3 ′ is “at the time of driving force restriction control”.

As another example, in the driving force recovery control, the driving force of the vehicle as shown by the solid line between the time t _A3 and t _{A3 'point,} normally when the driving force in the change rate R _P with time It may be raised toward a predetermined target value (for example, intermediate driving force F _MD ) less than F _{NM, and} may be maintained at the predetermined target value along the broken line in FIG. 13 from the time point t _A3 ′.

In FIG. 13, the power shut-off control is executed between the time point t _{A1 and the} time point t _A2 prior to the execution of the driving force limit control. However, a fail-safe process in which the power shut-off control is not executed may be performed. . If the driving force limiting control is executed without executing the power cut-off control as described above, for example, at time t _B1 corresponding to time t _A1 (see FIG. 13) as shown in FIG. By executing the driving force limiting control, the driving force of the vehicle is reduced from the normal driving force F _NM to the limiting driving force F _DP (driving force at the time of driving force limiting control), and then the driving force recovery is performed. By executing the control, the driving force of the vehicle is increased.

This embodiment has the following effects (A1) to (A14). (A1) According to the present embodiment, the ECT-ECU 114 does not obtain the abnormality detection result of the abnormality detecting means 132 via one communication path 134 of the first path 136 and the second path 138, and the other communication path. When the abnormality detection result is obtained via 134, the power transmission permission unit 146 gives the power transmission permission to the driving force limiting unit 154. Then, when the power transmission permission is given, the driving force limiting means 154 limits the driving force of the vehicle lower than the normal driving force _FNM in a state where the vehicle can generate the driving force. Force limit control is executed. Further, after executing the driving force limiting control, the driving force recovery means 156 executes the driving force recovery control, for example, after a predetermined driving force limiting time time_df has elapsed since the start of the driving force limiting control. It is raised to a low intermediate driving force F _MD than normal when the driving force F _NM driving force of the vehicle. In this way, when the abnormality detection result is obtained, after providing a grace period that allows the driver to recognize that the driving force of the vehicle is limited in order to ensure safety in vehicle travel, its driving force so that the are relaxed its limit is close to the normal-time driving force F _NM. As a result, it is possible to prevent the driver's convenience from deteriorating while ensuring safety in vehicle travel.

(A2) According to the present embodiment, the driving force recovery means 156, for example, in the driving force recovery control, after the start of the driving force limit control, the normal driving force F _NM or a predetermined value less than the normal driving force F _{NM as} time elapses. target value (e.g., the intermediate driving force F _MD) toward a predetermined change rate R _P may increase the driving force of the vehicle. By doing so, the driving force of the vehicle does not change suddenly, and sufficient safety can be ensured when the driving force of the vehicle increases.

(A3) The driver usually suppresses the vehicle speed V if there is an obstacle or the like near the vehicle, and increases the vehicle speed V if there is no such obstacle or the safety is sufficiently high. In this respect, according to the present embodiment, the driving force recovery means 156, in the driving force recovery control, when increasing the driving force of the vehicle by the change rate R _P with time, the change rate R _P The vehicle driving force may be changed so that the driving speed of the vehicle increases faster as the vehicle speed V increases. In such a case, if it can be determined based on the vehicle speed V that sufficient safety can be ensured even if an abnormality of the shift-by-wire control device 103 appears in the vehicle travel, the vehicle is driven early according to the vehicle speed V. The restriction on the force can be relaxed, and the convenience of the driver can be improved while ensuring the safety in traveling the vehicle.

(A4) According to the present embodiment, in the driving force limiting control, the limiting driving force F _DP is desirably a predetermined vehicle driving force (driving force limit value) set to be as low as possible to enable vehicle travel. ). In this way, it is possible to make the vehicle travelable while ensuring safety in vehicle travel.

(A5) If either one of the first path 136 and the second path 138 is normal and the other communication path 134 is abnormal, the abnormality detecting unit 132 sets the shift-by-wire control device 103. The ECT-ECU 114 may obtain the abnormality detection result (SBW abnormality signal S _FL ) only through the other communication path 134 even though no abnormality is detected. In this respect, according to this embodiment, the power shut-off means 148, when the ECT-ECU 114 receives the SBW abnormal signal _{S FL} via the first path 136 or second path 138, the driving force limiting control Prior to execution, power cutoff control for cutting off the power transmission path is executed. Then, the ECT-ECU 114 does not obtain the abnormality detection result (SBW abnormality signal S _FL ) via the one communication path 134 of the first path 136 and the second path 138 and the abnormality via the other communication path 134. When obtaining the detection result continues for a predetermined normal state determination time time_nf (predetermined time time_nf), the power transmission permission unit 146 gives the power transmission permission to the driving force limiting unit 154, and further, the driving force limiting unit When the power transmission permission is given, 154 causes the power cut-off means 148 to stop the power cut-off control and executes the drive force limiting control. Therefore, it can be determined that the abnormality detection unit 132 has not detected an abnormality in the shift-by-wire control device 103 based on the fact that the abnormality detection result has not been continuously obtained via the one communication path 134, and the determination is made. Until it is possible, sufficient vehicle safety can be ensured by blocking the power transmission path by executing the power cutoff control. In addition, after it can be determined that no abnormality of the shift-by-wire control device 103 is detected based on the fact that the abnormality detection result cannot be obtained via the one communication path 134 and the normal state determination time time_nf continues. The vehicle is allowed to travel, and the convenience of the driver can be improved while ensuring the safety in traveling the vehicle.

(A6) according to the present embodiment, the power shut-off means 148, when the ECT-ECU 114 receives the SBW abnormal signal _{S FL} via the first path 136 or second path 138, the driving force limiting control prior to execution, since performing the power interruption control for interrupting the power transmitting path, even through any first path 136 and second path 138, the ECT-ECU 114 receives the SBW abnormal signal _{S FL} Without waiting for the above, the power cutoff control as the fail-safe process can be executed early. As a result, a safe vehicle state is ensured early.

  (A7) According to the present embodiment, execution of the power cutoff control means that a neutral pattern is formed to cut off the power transmission path from the engine 10 to the drive wheels (power transmission path in the automatic transmission 14). Therefore, the possibility that the vehicle travels against the driver's intention due to the abnormality of the shift-by-wire control device 103 can be eliminated.

(A8) According to the present embodiment, preferably, when the power shut-off means 148 stops (interrupts) the power shut-off control (neutral pattern formation), the driving force of the vehicle is driven at a normal time after the stop. Even when returning to the force F _NM or when the driving force limiting control is executed, the power cutoff control is performed after a predetermined return hold time time_rv has elapsed from the start of execution of the power cutoff control. Cancel. In this case, control hunting can be prevented because execution of the power shut-off control is not stopped at all after the start of execution of the power cutoff control.

(A9) According to the present embodiment, preferably, when the power shut-off means 148 stops the power shut-off control (neutral pattern formation), the driving force of the vehicle is normal driving force F _NM after the stop. Even when the driving force limiting control is executed, the power cutoff control is stopped when the return permission condition is satisfied. In such a case, when the vehicle travel is started with the suspension of the power shut-off control, the safety at that time can be improved.

(A10) According to the present embodiment, when the power cut-off control is executed by the power cut-off means 148, the power cut-off permission means 146 determines that the executed power cut-off control is the SBW abnormality signals S1 _FL and S2 _FL. The neutral pattern formation histories hst1_n and hst2_n for determining which of the receptions is received are stored. Further, the power transmission permission means 146 outputs the histories hst1_n and hst2_n to the power cutoff means 148, and the power cutoff means 148 Determines whether to resume execution of the power shutoff control based on the neutral pattern formation histories hst1_n and hst2_n. Accordingly, when the power cutoff control is stopped when the ECT-ECU 114 and SBW abnormal signal _{S FL} via the first path 136 or second path 138 is receiving, the power shut-off means 148, the power cut-off It is possible to easily determine whether or not to resume the execution of control.

  (A11) According to the present embodiment, when the neutral pattern is formed as the fail-safe process, the automatic transmission 14 can be operated regardless of the shift position (manual valve position) of the manual valve 70 controlled by the SBW actuator 68. Therefore, even if the manual valve position is unclear because the shift positions indicated by the signals of the shift position sensors 67 and 118 are inconsistent with each other. In addition, the power transmission path in the automatic transmission 14 can be shut off, and safety can be ensured.

  (A12) According to this embodiment, when the neutral pattern is formed, the frictional engagement elements (clutch C1, clutch C2) for the forward movement of the automatic transmission 14 and the frictional engagement elements for the reverse movement (clutch C1, clutch C2). Since both the brake B2 and the brake B3) are released, the power transmission path in the automatic transmission 14 is reliably cut off regardless of whether the manual valve position is the forward position or the reverse position. be able to.

  (A13) According to the present embodiment, the automatic transmission 14 is a transmission that can shut off power regardless of the position of the manual valve. Therefore, the automatic transmission is surely reliable regardless of the position of the manual valve. Power transmission in 14 can be cut off.

  (A14) According to this embodiment, when the vehicle speed determining means 150 determines that the vehicle speed V is equal to or lower than the predetermined vehicle speed V1 experimentally set in the low vehicle speed range, the power shut-off means 148 receives the first reception. Since the power shut-off control (neutral pattern formation) is executed based on the judgment of the judging means 142 and the second reception judging means 144, sudden torque loss due to power shut-off in the middle / high vehicle speed range is prevented. Note that if the power transmission path is interrupted in the middle / high vehicle speed range, the vehicle may become unstable and the operability may be reduced. Thus, the power shut-off control is not executed in the middle / high vehicle speed range, thereby avoiding a decrease in the operability of the vehicle.

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

For example, in FIG. 8 of the present embodiment, the electronic control unit 104 (ECT-ECU 114) has the power cut-off means 148, but the power cut-off means 148 may be omitted. In such a case, the power transmission permission unit 146 determines that one of the first reception determination unit 142 and the second reception determination unit 144 has obtained the normal detection result, while the other receives the abnormality described above. detecting if the result was judged obtained indicating the will, without waiting for the one above performs normal state confirmation decision X _NF, immediately the power transmission permission (driving force limiting control execution permission) the driving force limiting means 154 To give. Then, the driving force of the vehicle changes as shown in FIG. 14, for example.

  In the present embodiment, the ECT-ECU (second control unit) 114 includes a power transmission permission unit 146, a power cutoff unit 148, a driving force limiting unit 154, and a driving force recovery unit 156, independently of each other. However, the means 146, 148, 154, and 156 do not have to be independent of each other. For example, a part or all of them may constitute one driving force control means.

  Further, in this embodiment, the communication path 134 between the SBW-ECU 112 and the ECT-ECU 114 is two systems of the first path 136 and the second path 138, but is a communication path 134 of three or more systems. Also good.

  In the present embodiment, as a communication method of the communication path 134, so-called CAN communication is shown as an example, but the communication method is not limited. Further, the communication methods of the first route 136 and the second route 138 may be the same or different from each other.

  In the present embodiment, the signal transmitted through the first path 136 and the second path 138 is an electrical signal, but the signal transmitted may be an optical signal, and the signal format is not limited. .

  In the present embodiment, the normal state determination time time_nf is the same value for both the first route 136 and the second route 138, but may be a different value for each communication route 134. The normal state determination time time_nf may be set shorter as the communication speed of the communication path 134 is higher.

  In the present embodiment, the communication speeds of the first path 136 and the second path 138 may be the same or different from each other.

In the present embodiment, the abnormality detecting means 132, if when an abnormality is detected in the shift-by-wire control unit 103 outputs the SBW abnormal signal S _FL, detects the normal state of the shift-by-wire control device 103 Although not output SBW abnormal signal S _FL is, the signal output of the inverse of the pattern, that is, when detecting the normal state of the shift-by-wire control unit 103 outputs a signal indicating the normal state, the shift-by-wire control When an abnormality of the device 103 is detected, the signal indicating the normal state may not be output. Further, the abnormality detection unit 132 may output a signal indicating the state of the shift-by-wire control device 103, regardless of whether the abnormality is normal or normal.

  Further, in the flowcharts shown in FIGS. 9 to 11 of the present embodiment, SA3, SA5, SA6, SA7, SA10, SA12, SA13, SA14, SA20, and SA24 are not essential steps, but a part of those steps. Or the flowchart which does not have all may be sufficient.

  In this embodiment, the power shut-off means 148 stores the neutral pattern formation histories hst1_n and hst2_n, but may not store such histories hst1_n and hst2_n.

  Further, in the present embodiment, the neutral pattern formation is such that the hydraulic control circuit 40 is controlled so that the forward and reverse shift stages are not established, but for example, the torque converter 12 and the automatic transmission 14 The power transmission path may be cut off by providing a power cut-off clutch on the input shaft 32 therebetween. In short, the neutral pattern formation only needs to be able to block the rotation of the engine 10 from being transmitted to the drive wheels regardless of whether it is moving forward or backward.

  Further, in this embodiment, the engine-driven vehicle generates power by burning fuel. However, there are various types of vehicles such as an electric vehicle driven by an electric motor or a hybrid vehicle provided with a plurality of driving power sources for driving. The present invention is suitably applied to a shift-by-wire control device (shift-by-wire control device) for a vehicle. That is, in the present invention, the driving power source for travel, the type of transmission, and the like are not particularly limited. For example, the present invention can be applied to a continuously variable transmission such as a CVT capable of continuously changing the speed ratio γ without being limited to a stepped transmission.

  In the present embodiment, the automatic transmission 14 constitutes a part of the power transmission path, but a vehicle power transmission device 8 without the automatic transmission 14 can also be considered. Further, the automatic transmission 14 may be replaced with a manual transmission.

  In the present embodiment, the vehicle power transmission device 8 is for FF vehicles, but the drive system is not particularly limited, and may be for FR vehicles or four-wheel drive vehicles.

  The type of the shift lever 66 is not limited to the present embodiment. For example, a switch that can select a plurality of types of shift positions such as a push button switch and a slide switch, or a driver's operation regardless of manual operation. A device that can switch a plurality of types of shift positions in response to sound, a device that can switch a plurality of types of shift positions by operating a foot, or the like may be used. That is, the present invention can be applied to any configuration that can convert a shift operation into an electrical signal.

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

1 is a schematic diagram of a vehicle power transmission device to which the present invention is preferably applied. It is a figure which shows the action | operation table | surface explaining the relationship between the several gear stage of the automatic transmission of FIG. 1, and the engagement release state of a friction engagement element. FIG. 2 is a hydraulic circuit diagram showing portions related to a hydraulic pressure supply device, clutches C1 and C2, and brakes B1 to B3 in a hydraulic control circuit provided in the vehicle power transmission device of FIG. It is a figure explaining the operation position of the shift lever of FIG. FIG. 4 is an enlarged circuit diagram showing the vicinity of a fail-safe valve in the hydraulic circuit diagram of FIG. 3. FIG. 4 is an enlarged circuit diagram showing the vicinity of a second brake control valve in the hydraulic circuit diagram of FIG. 3. In the vehicle power transmission device of FIG. 1, in accordance with an instruction to change the shift range by the driver, specifically, in response to an operation of the shift lever by the driver, the manual valve shift position is electrically switched to automatically shift. FIG. 2 is a block diagram illustrating a control system of a shift-by-wire control device that executes gear shift control of the machine, and is a diagram illustrating a main part of the configuration of the shift-by-wire control device. It is a functional block diagram explaining the principal part of the control function by the electronic controller of FIG. Main control operation of the electronic control device of FIG. 7, i.e., illustrating a control operation for executing the power cutoff control, the driving force limiting control, the driving force recovery control as a fail-safe processing based on the SBW abnormal signal S _FL It is a flowchart, Comprising: It is the 1st figure of three set drawings. Main control operation of the electronic control device of FIG. 7, i.e., illustrating a control operation for executing the power cutoff control, the driving force limiting control, the driving force recovery control as a fail-safe processing based on the SBW abnormal signal S _FL It is a flowchart, Comprising: It is the 2nd figure of three set drawings. Main control operation of the electronic control device of FIG. 7, i.e., illustrating a control operation for executing the power cutoff control, the driving force limiting control, the driving force recovery control as a fail-safe processing based on the SBW abnormal signal S _FL It is a flowchart, Comprising: It is the 3rd figure of three set drawings. FIG. 11 is a flowchart for explaining a main part of a control operation in SA15 and SA18 of FIG. 10, that is, a control operation for executing fail-safe processing that enables vehicle travel. FIG. 13 is a time chart for explaining the control operation shown in the flowcharts of FIGS. 9 to 12, specifically, when the ECT-ECU (second control unit) is traveling at a vehicle speed equal to or lower than a predetermined vehicle speed, the SBW abnormality signal is displayed. When the state where the S1 _FL is received and the SBW abnormality signal S2 _FL is not received continues, the power cutoff control, the driving force limit control, and the driving force recovery control are sequentially executed as an example. It is a time chart for demonstrating the change of a driving force. FIG. 13 is a time chart illustrating an example of a change in the driving force of the vehicle in order to explain another control pattern in which the change in the driving force of the vehicle is different. Specifically, the power cut-off control is not executed and the fail-safe control is performed. It is the time chart which illustrated the case where driving force restriction control and driving force recovery control were performed sequentially as processing.

Explanation of symbols

103: Shift-by-wire control device 112: SBW-ECU (first control unit)
114: ECT-ECU (second control unit)
132: Abnormality detection means 134: Communication path 136: First path 138: Second path 148: Power cutoff means 154: Driving force limiting means 156: Driving force recovery means

Claims (5)

A first control unit that outputs a control signal related to vehicle travel, a second control unit that executes control related to vehicle travel based on the control signal, and the control signal between the first control unit and the second control unit. A vehicle-by-wire control device including a communication path for transmission,
The communication path includes a first path and a second path parallel to each other,
The first control unit includes abnormality detection means for detecting an abnormality of the shift-by-wire control device,
The second controller is
When the abnormality detection result is obtained via the other communication path without obtaining the abnormality detection result of the abnormality detection means indicating the abnormality via the one communication path of the first route and the second route In a state where the vehicle can generate a driving force, the driving force limiting control is performed to limit the driving force of the vehicle lower than the normal driving force when the abnormality detection result is not obtained through any communication path. Driving force limiting means to
Driving force recovery control that sets the driving force of the vehicle to a driving force that is lower than the normal driving force and higher than the driving force during the driving force limiting control after a predetermined driving force limit time has elapsed since the start of the driving force limiting control. And a drive-by force recovery means for executing the vehicle. The driving force recovery means increases the driving force of the vehicle at a predetermined change rate as time passes after the start of the driving force limit control in the driving force recovery control. Vehicle shift-by-wire control device. 3. The vehicle shift-by-wire according to claim 2, wherein, in the driving force recovery control, the driving force recovery means changes the change rate so that the driving force of the vehicle increases faster as the vehicle speed increases. Control device. 4. The vehicle driving force according to claim 1, wherein the driving force during the driving force limiting control is a driving force of a predetermined vehicle that is set as low as possible so that the vehicle can travel. 5. Shift-by-wire control device. When the second control unit obtains the abnormality detection result via the other communication path, a power cutoff that cuts off a power transmission path prior to the execution of the driving force limiting control by the driving force limiting means Including means,
When the driving force limiting means continues to obtain the abnormality detection result via the other communication path without obtaining the abnormality detection result via the one communication path, the power interruption means The vehicle shift-by-wire control device according to any one of claims 1 to 4, wherein the power transmission path is interrupted and the driving force limiting control is executed.

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