JP2009108922A - Control device of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device of a vehicle which can improve limp-home performance while conducting fail safe when a fail occurs in a shift-by-wire. <P>SOLUTION: A gradient is detected by the detection result of a G sensor 19 when the shift range of an AT manual shaft 13 is switched when a shift-by-wire ECU (SBW-ECU)11 is failed, and only when it is detected that the shift range is switched to a reverse range (R) in a climbing lane, and switched to a forward range in a downhill lane (D), an ECT-ECU 14 blocks a drive force by controlling an AT solenoid 15. By this, the vehicle can be moved to a direction which a driver desires at the occurrence of the fail in the shift-by-wire, and also can be moved to a desired position, thus improving the limp-home performance while conducting the fail safe. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle control device including a shift-by-wire system.

  Conventionally, in an automatic transmission used in an automobile, a select lever is mechanically coupled to a shift range switching valve that controls shift range switching of the automatic transmission, and a predetermined lever is operated by a driver operating the select lever. The shift range of the automatic transmission has been switched by switching to the shift range position.

  Further, in recent years, an input device such as a select lever and an automatic transmission are not provided with a mechanical link, and are switched to a target shift range by an actuator that responds to an electrical target shift range signal. A shift-by-wire shift range switching device has been proposed.

  In this shift-by-wire shift range switching device, when an abnormality occurs and the control of the actuator by the by-wire control circuit stops, the shift range of the automatic transmission is fixed to a travel range that is contrary to the intention of the driver of the vehicle. In order to prevent the vehicle from running, for example, as a fail-safe function, the shift range of the automatic transmission is fixed to the N range (neutral position) when an abnormality is detected, the engine torque is reduced, or the brake is activated. Or automatic operation control is prohibited (see, for example, Patent Document 1).

As another fail-safe function, the shift range position is forcibly set to the D range (forward position), the P range (parking position), or when the actual shift range is other than the P range. I try to emit.
JP 2006-336717 A

  However, in a fail-safe function such as a conventional shift range switching device, the shift range of the automatic transmission is fixed to a specific shift range when a failure occurs, and is fixed to a shift range against the driver's intention. There is a risk that. In particular, if the driving force is fixed to a shift range where the driving force is not transmitted, such as a shift range or a P range that travels in a direction opposite to the driver's intention, there is a problem that the driver cannot proceed in a desired direction. Furthermore, there is a problem that if the shift range is fixed regardless of whether the lever is operated or not, the vehicle must be stopped in a place that does not conform to the driver's intention when the failure is detected. .

  The present invention has been made in order to solve such a conventional problem. When a shift-by-wire failure occurs, the vehicle can move in the direction desired by the driver, and limp home while performing fail-safe. An object of the present invention is to provide a vehicle control device capable of improving performance.

  In order to solve the above problems, a vehicle control apparatus according to the present invention detects (1) a shift range designated position selected by a driver of a vehicle, and an automatic transmission according to the detected shift range designated position. A fail detection means for detecting the occurrence of a failure of the shift-by-wire control unit that electrically controls the actuator that switches the shift range of the shift-by-wire, and a drive force is not required when the occurrence of a failure of the shift-by-wire control unit is detected Exclusion range determination means for determining the shift range of the direction as an exclusion shift range that can be excluded, range detection means for detecting the shift range of the automatic transmission, and the shift range detected by the range detection means are the exclusion ranges. A drive that cuts off the driving force that drives the vehicle when the exclusion shift range is determined by the range determining means. It has a structure obtained by comprising: the power control means.

  With this configuration, when the shift-by-wire failure occurs, the driving force that drives the vehicle is cut off only when the shift range is switched to a direction that does not require the driving force. The driving force can be secured, the vehicle can move in the direction desired by the driver, and the limp home performance can be improved.

  The vehicle control device according to the present invention is the vehicle control device according to (1), further comprising: (2) vehicle inclination direction detection means for detecting the vehicle inclination direction; The shift range in the direction in which the vehicle can travel without the driving force is determined as the exclusion shift range based on the vehicle inclination direction detected by the vehicle inclination means.

  With this configuration, the driving force is cut off only in the shift range in the direction in which the vehicle can run without driving force due to the road gradient. Movement in the direction is possible, the vehicle can be moved to a desired position, and limp home performance can be improved.

  Furthermore, the vehicle control device according to the present invention is the vehicle control device according to the above (1) or (2), further comprising (3) gaze direction detection means for detecting the gaze direction of the driver, and the exclusion. The range determining unit determines a shift range that travels in a direction opposite to the line-of-sight direction detected by the line-of-sight direction detecting unit as the exclusion shift range.

  With this configuration, the driving force is cut off only for the shift range in the direction opposite to the line of sight of the driver of the vehicle, so it is possible to avoid traveling in a direction contrary to the driver's intention and improve the fail-safe function. be able to.

  Furthermore, the vehicle control device according to the present invention is the vehicle control device according to any one of (1) to (3), wherein (4) the range detection means performs the shift-by-wire control by the fail detection means. A shift range switching operation of the automatic transmission is detected, and the driving force control means detects the shift range switching operation by the range detection means. In the exclusion shift range determined by the exclusion range determination means, the driving force for driving the vehicle is cut off.

  With this configuration, the driving force is cut off only when the shift range is switched and the shift range is an excluded shift range. Therefore, even if a shift-by-wire failure occurs, the previous shift until the shift range is switched. The vehicle can travel in the shift range, and the limp home performance can be improved.

  According to the present invention, when a shift-by-wire failure occurs, the driving force that drives the vehicle is cut off only when the shift range is switched to a direction that does not require the driving force. The driving force in the direction can be ensured, the vehicle can move in the direction desired by the driver, and a vehicle control device that improves limp home performance can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the electronic control unit is referred to as “ECU”.

(First embodiment)
First, the configuration will be described.

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

  As shown in FIG. 1, a vehicle control device 10 mounted on a vehicle includes a shift-by-wire ECU (hereinafter referred to as SBW-ECU) 11, an SBW actuator 12, an AT manual shaft 13, an electronically controlled transmission ECU ( (Hereinafter referred to as ECT-ECU) 14, AT solenoid 15, engine ECU (hereinafter referred to as ENG-ECU) 16, electronic throttle 17, brake ECU 18, G sensor 19, body ECU 20, and line-of-sight detection sensor 21 And.

  The SBW-ECU 11, the ECT-ECU 14, the ENG-ECU 16, the brake ECU 18 and the body ECU 20 are all electric circuits mainly composed of a microcomputer centering on the CPU, and temporarily store data in addition to the CPU. And an input / output interface circuit including an A / D converter and the like, and are electrically or optically interconnected via an in-vehicle LAN line 31 or a serial communication line (not shown). Yes. Further, the SBW-ECU 11, the ECT-ECU 14, the ENG-ECU 16, the brake ECU 18 and the body ECU 20 are electrically connected to a battery (not shown) which is a main power source of the vehicle, and operate by being supplied with electric power from the battery. It has become.

  The SBW-ECU 11 is electrically connected to an SBW actuator 12 that drives the AT manual shaft 13 and a range lever (not shown). The SBW-ECU 11 inputs a shift range (hereinafter referred to as “command range”) signal commanded by a lever operation of the driver of the vehicle from a shift position sensor (not shown), and controls the SBW actuator 12 based on the input signal. It comes to control. The SBW actuator 12 is controlled by the SBW-ECU 11 to switch the AT manual shaft 13 to the command range. The shift range includes a forward (D) range and a reverse (R) range as a travel range, a parking (P) range and a neutral (N) range as a non-travel range.

  The SBW-ECU 11 and the ECT-ECU 14 are connected by a direct line and CAN. The SBW-ECU 11 is configured to output a fail determination signal to the ECT-ECU 14 via the straight line and CAN. For example, the SBW-ECU 11 outputs the same signal such as a “01” signal that changes at the same time interval to each of the direct line and the CAN.

  The ECT-ECU 14 determines whether or not the signals input from the SBW-ECU 11 via the direct line and the CAN are the same, and if not, determines that a failure has occurred in the SBW-ECU 11. It is like that. The ECT-ECU 14 is connected to the AT solenoid 15 and drives the AT solenoid 15 based on the shift range of the AT manual shaft 13 to switch the shift range of the automatic transmission.

  The ENG-ECU 16 controls the electronic throttle 17 in accordance with an operation of an accelerator pedal (not shown). With this control, the engine speed (hereinafter referred to as “engine speed”) and output torque (hereinafter referred to as “engine torque”) are adjusted.

  The brake ECU 18 is electrically connected to the G sensor 19. The G sensor 19 detects the inclination of the vehicle. The brake ECU 18 detects that the vehicle is tilted forward by the detection signal input from the G sensor 19, that is, the front of the vehicle is downward, or the vehicle is tilted rearward, that is, the rear of the vehicle is downward. It is designed to detect if there is any.

  The body ECU 20 is electrically connected to the line-of-sight detection sensor 21. The line-of-sight detection sensor 21 is constituted by, for example, an eye camera or the like, and detects the direction of the line of sight of a vehicle occupant sitting in the driver's seat. The body ECU 20 detects whether the driver is facing the front of the vehicle or the rear of the vehicle based on the detection signal input from the line-of-sight detection sensor 21.

  In the present embodiment, the SBW-ECU 11 constitutes the shift-by-wire control unit in the present invention, and the ECT-ECU 14 includes the fail detection means, the exclusion range determination means, the range detection means, and the driving force control means in the present invention. It is composed. Further, the brake ECU 18 constitutes the vehicle tilt direction detecting means in the present invention.

  Here, the “shift range in a direction that does not require driving force” determined as the excluded shift range in the exclusion range determining means is a direction in which the vehicle can be moved without transmitting the driving force to the wheels. Say. For example, the forward (D) range when the vehicle is tilted forward and the reverse (R) range when the vehicle is tilted backward.

  Next, the operation will be described.

  FIG. 2 is a flowchart of the shift-by-wire fail process in the vehicle control apparatus according to the first embodiment of the present invention.

  The flowchart shown in FIG. 2 is a program for shift-by-wire fail processing executed by the CPU of the ECT-ECU 14, and this shift-by-wire fail processing program is stored in the ROM of the ECT-ECU 14. The shift-by-wire fail process starts when the ignition switch of the vehicle is turned on by the driver, and ends when the ignition switch is turned off by the driver.

  In this shift-by-wire failure process, when the shift range is switched when a shift-by-wire failure occurs, only the driving force in the downward direction of the vehicle is cut off and travel when the failure occurs is restricted.

  In the shift-by-wire fail process, first, the SBW-ECU 11 performs a fail determination (step S11). The failure determination method of the SBW-ECU 11 is, for example, as described above, when the ECT-ECU 14 inputs the same signal from the SBW-ECU 11 through a plurality of paths, and the input signals are not the same, the SBW-ECU 11 Is determined to have failed. When the SBW-ECU 11 determines that the failure has occurred, the process proceeds to step S12. When it is determined that the failure has not occurred, the process ends.

  When the SBW-ECU 11 determines that a failure has occurred, it determines whether or not a shift range switching operation by shift-by-wire has been detected (step S12). Here, the shift range switching is determined based on whether or not the shift range of the AT manual shaft 13 has been switched by the ECT-ECU 14. If shift range switching is detected, the process proceeds to step S13. If shift range switching is not detected, the process ends.

  If shift range switching is detected, gradient detection is performed (step S13). In this gradient detection, the brake ECU 18 detects the inclination of the vehicle based on the detection signal detected by the G sensor 19, and performs gradient detection. Here, it is detected only whether the vehicle is tilted forward or backward. It is also possible to detect the inclination with respect to a 360 degree direction including the left and right sides of the vehicle, and to perform control in consideration of the direction of the drive wheels and the operation direction of the steering wheel.

  Next, it is determined whether or not the shift range is changed in the downward direction (step S14). Here, when the front of the vehicle is low, when the shift range is the forward (D) range, it is determined that the shift range is switched in the downward direction, and the rear of the vehicle is low When the shift range is the reverse (R) range, it is determined that the shift range is switched in the downward direction. If it is determined that the shift range is switched in the down direction, the process proceeds to step S15. If it is determined that the shift range is not switched in the down direction, the process proceeds to step S16.

  If it is determined that the shift range is switched in the downward direction, the driving force is cut off and travel after the shift range is switched is regulated (step S15). As a method for interrupting the driving force, there are, for example, a method of stopping the engine, releasing a frictional engagement element such as a clutch, or fully closing the electronic throttle 17.

  On the other hand, when it is determined that the shift range is not switched in the downward direction (No in step S14), the continuation of the travel after the shift range is switched is permitted (step S16), and the automatic transmission of the automatic transmission is set to the AT solenoid 15. Perform shift range switching operation.

  Thus, the vehicle control apparatus 10 according to the present embodiment enables the vehicle to move in the direction desired by the driver when a shift-by-wire failure occurs. Therefore, limp home performance can be improved while performing fail safe. In particular, since the driving force is cut off only in the shift range in the direction in which the vehicle can run without driving force due to the road gradient, the driving in the upward or downward direction with the driving force cut off can be driven by the vehicle's own weight, and in all directions. Can be moved, the vehicle can be moved to a desired position, and limp home performance can be improved.

  In addition, since fail control is performed only when the shift range is switched, even if a shift-by-wire failure occurs, it is possible to travel with the previous shift range until the shift range is switched, and limp home performance Can be improved.

  In the present embodiment, the SBW-ECU 11 and the ECT-ECU 14 are connected by a continuous line and CAN, and the ECT-ECU 14 determines whether or not a failure has occurred in the SBW-ECU 11. However, the present invention is not limited to this, and the SBW-ECU 11 and the ENG-ECU 16 are connected by a direct line and a CAN, and the ENG-ECU 16 determines whether or not a failure has occurred in the SBW-ECU 11. A signal indicating the result may be output to the ECT-ECU 14.

(Second Embodiment)
First, the configuration will be described.

  The configuration of the vehicle control device 10 according to the present embodiment is the same as the configuration of the vehicle control device 10 according to the first embodiment described above, and the shift-by-wire stored in the ROM of the ECT-ECU 14. The only difference is that the program for fail processing and the control based on the gaze direction detection by the gaze detection sensor 21 are performed instead of the gradient detection by the G sensor 19.

  In the following description, the same components and processes as those in the first embodiment will be described in detail using the same reference numerals and focusing on the differences. In the present embodiment, the body ECU 20 constitutes the line-of-sight direction detection means in the present invention. In the following embodiment, the vehicle control is performed using the driver's line-of-sight detection by the body ECU 20 instead of the vehicle inclination detection by the brake ECU 18. The vehicle may be controlled using both the detection of the driver's line of sight by the ECU 20.

  Next, the operation will be described.

  FIG. 3 is a flowchart of the shift-by-wire fail process in the vehicle control apparatus according to the second embodiment of the present invention. In addition, the shift-by-wire fail process is started when the ignition switch of the vehicle is turned on by the driver as in the shift-by-wire fail process in the above embodiment, and the ignition switch is turned off by the driver. finish.

  In this shift-by-wire fail process, when the shift range is switched when a shift-by-wire failure occurs, only the driving force in the direction opposite to the direction of the line of sight of the driver of the vehicle is cut off, and travel when the failure occurs is restricted.

  In the shift-by-wire fail process, first, the SBW-ECU 11 performs a fail determination (step S11). When the SBW-ECU 11 determines that the failure has occurred, the process proceeds to step S12. When it is determined that the failure has not occurred, the process ends.

  When the SBW-ECU 11 determines that a failure has occurred, it determines whether or not a shift range switching operation by shift-by-wire has been detected (step S12). If shift range switching is detected, the process proceeds to step S21. If shift range switching is not detected, the process ends.

  When the shift range switching is detected, the line-of-sight direction is detected (step S21). In this gaze direction detection, the body ECU 20 detects the direction of the gaze of the driver of the vehicle based on the detection signal detected by the gaze detection sensor 21. Here, the direction of the driver's line of sight is detected only for the front of the vehicle or the rear of the vehicle. It is also possible to detect the direction of the line of sight with respect to a 360 degree direction including the left and right sides of the vehicle, and perform control in consideration of the direction of the drive wheels and the operation direction of the handle.

  In addition, the determination of the line of sight takes into account not only whether the driver's line of sight is facing forward or backward, but also when the line of sight is facing the rearview mirror, back monitor, etc. If the line of sight is facing the mirror, it is determined that the driver's line of sight is behind. It is assumed that the vehicle occupant sitting in the driver's seat is determined as the vehicle driver.

  Next, it is determined whether or not the shift range is switched in the direction opposite to the line of sight (step S22). Here, when the driver's line-of-sight direction is forward, when the switching shift range is the reverse (R) range, it is determined that the shift range is switched in the opposite direction to the line of sight, and the driver's line-of-sight direction If the shift range is the forward (D) range, it is determined that the shift range is switched in the direction opposite to the line of sight. If it is determined that the shift range is switched in the direction opposite to the line of sight, the process proceeds to step S15. If it is determined that the shift range is not switched in the direction opposite to the line of sight, the process proceeds to step S16.

  If it is determined that the shift range is switched in the direction opposite to the line of sight, the driving force is cut off and travel after the shift range is switched (step S15).

  On the other hand, when it is determined that the shift range is not switched in the direction opposite to the line of sight (No in step S22), the continuation of the travel after the shift range is switched is permitted (step S16), and the automatic transmission with respect to the AT solenoid 15 is performed. Perform the shift range switching operation of the machine.

  Thus, the vehicle control apparatus 10 according to the present embodiment cuts off the driving force only for the shift range in the direction opposite to the line of sight of the driver of the vehicle. Therefore, traveling in a direction contrary to the driver's intention can be avoided, and the fail-safe function can be improved.

  As described above, the vehicle control apparatus according to the present invention cuts off the driving force for driving the vehicle only when the shift range in which the driving force is not required is switched when a shift-by-wire failure occurs. Therefore, while performing fail-safe, the driving force in the necessary direction can be secured, the vehicle can be moved in the direction desired by the driver, and the limp home performance can be improved. It is useful as a control device for a vehicle equipped with a by-wire system.

1 is a schematic block configuration diagram of a vehicle control device according to a first embodiment of the present invention. It is a flowchart of the shift-by-wire fail process in the control apparatus of the vehicle which concerns on the 1st Embodiment of this invention. It is a flowchart of the shift-by-wire fail process in the vehicle control apparatus which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

10 vehicle control device 11 SBW-ECU (shift-by-wire control unit)
12 SBW actuator 13 AT manual shaft 14 ECT-ECU (failure detection means, exclusion range determination means, range detection means, driving force control means)
15 AT solenoid 16 ENG-ECU
17 Electronic throttle 18 Brake ECU (vehicle tilt detection means)
19 G sensor 20 Body ECU (Gaze direction detection means)
21 Gaze detection sensor

Claims (4)

Generation of a fail of a shift-by-wire control unit that detects a shift range designated position selected by a vehicle driver and electrically controls an actuator that switches the shift range of the automatic transmission according to the detected shift range designated position Fail detection means for detecting
Exclusion range determination means for determining a shift range in a direction that does not require driving force as an exclusion shift range that can be excluded when occurrence of a failure of the shift-by-wire control unit is detected;
Range detecting means for detecting a shift range of the automatic transmission;
When the shift range detected by the range detection means is the exclusion shift range determined by the exclusion range determination means, driving force control means for cutting off the driving force for driving the vehicle;
A vehicle control device comprising: Vehicle inclination direction detecting means for detecting the vehicle inclination direction;
The said exclusion range determination means determines the shift range of the direction which can drive | work without the said driving force as the said exclusion shift range by the inclination direction of the said vehicle detected by the said vehicle inclination means. The vehicle control device according to claim 1. Gaze direction detecting means for detecting the gaze direction of the driver,
The said exclusion range determination means determines the shift range which drive | works in the direction opposite to the gaze direction detected by the said gaze direction detection means as said exclusion shift range, The Claim 1 or Claim 2 characterized by the above-mentioned. Vehicle control device. The range detection means detects a shift range switching operation of the automatic transmission after the fail detection means detects a failure of the shift-by-wire control unit,
The driving force control means detects the shift range switching operation by the range detection means, and drives the vehicle when the switched shift range is the exclusion shift range determined by the exclusion range determination means. The vehicle control device according to any one of claims 1 to 3, wherein the driving force is interrupted.

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