JP6824391B2 - Electronic control device and control method to realize safe park lock - Google Patents

Description

The following disclosure relates to electronic controls and control methods that achieve safe park locks, and in particular can safely bring the vehicle into a park lock state even if incorrect information is transmitted from, for example, other electronic controls. Regarding electronic control devices and control methods.

To prevent unintentional movement of a parked vehicle, vehicles with automatic transmissions can typically turn off the ignition when the gear selector is in the park position. In relation to the control of the park lock, for example, the upper electronic control device (ECU) first sends a park lock request to the lower ECU in charge of the gear system to lock (park lock) the gear system. Then, a shutdown request is sent to shut down all ECUs. Since it is pre-parked, the vehicle should not start moving during and after the shutdown process, for example, if an external force is applied or the driver makes a mistake.

Patent Document 1 discloses a related technique.

Japanese Patent Publication No. 2009-30637

When considering further improvement in safety, there is room for improvement in the above-mentioned control. That is, when the ignition of the vehicle is off, if the lower ECU shuts down without receiving the park lock request from the upper ECU for some reason, a state in which the park lock is not performed may occur. For example, if the host ECU malfunctions or if the bus for communication malfunctions, such a situation may occur. In these cases, it may also be difficult for the driver to notice the malfunction.

The devices and methods disclosed below have been created in view of the above problems.

According to that aspect, the electronic control device is connected to the power source of the vehicle and one or more other electronic control devices to share information by communication to control the park lock. When the electronic control device detects that the power supply is turned off, the information includes a park lock request, and the park lock is not locked, the lock means for locking the park lock and the park lock are locked. If it is detected, the information includes a park lock detection means for including a park lock completion notification.

According to another aspect, the electronic controller detects the state of the vehicle's power supply and park lock, and also shares information, including at least one request, with one or more other electronic controllers by communication. .. The method of controlling the park lock executed by the electronic control device locks the park lock if it detects that the power supply is turned off, the information includes the park lock request, and the park lock is not locked. , Detecting whether or not the park lock is locked.

FIG. 1 is a block diagram of a vehicle including an electronic control device according to the present embodiment. FIG. 2 is a flowchart of control executed in the electronic control device according to the present embodiment. FIG. 3 is a flowchart showing details of the process of parklocking in FIG. FIG. 4 is a flowchart showing details of the process of releasing the park lock in FIG. FIG. 5 is a flowchart of control based on a modified example, which is executed when there is a request to release the park lock. FIG. 6 is a flowchart for shutdown control. FIG. 7A is an example flowchart that can be executed by replacing the portion represented by the alternate long and short dash line in FIG. FIG. 7B is a flowchart according to another example that can be executed by replacing the portion represented by the alternate long and short dash line in FIG.

Some exemplary embodiments will be described below with reference to the accompanying drawings.

With reference to FIG. 1, a typical vehicle 1 comprises, for example, an engine and a gear system including a transmission that transmits torque from the engine to each axle, and a plurality of programmable parts to electronically control each of these parts. It is equipped with an electronic control device (ECU). Each ECU includes a storage device that stores commands and data, and a microcontroller that can read these from the storage device and execute commands.

There are dozens of ECUs provided in a general vehicle, but only six of them, ECUs 11 to 21, are shown in FIG. These ECUs 11 to 21 read the state of each part of the vehicle by various sensors, and are connected to each other by a bus 31. The ECUs 11 to 21 communicate or share information by communication via, for example, a so-called controlled area network (CAN). Such information includes not only the read state but also requests for other ECUs, and each ECU controls each part by using these.

For example, the gear system includes a park lock 7 and a detecting means 9 for detecting the state (for example, locked or unlocked). The actuator and the detecting means 9 for driving the park lock 7 are electrically connected to the park lock ECU 11, and the park lock ECU 11 controls the park lock 7 based on the read information and the request from another ECU. Another ECU, for example, the ECU 13, is connected to the ignition switch 3 and transmits a request to each ECU according to the state (on or off) of the switch 3, and the state of the switch 3 is transmitted to the ECU 11 via the bus 31. Share with other ECUs including. The other ECUs 15 and 19 monitor the rotation of the axle, gear, and shaft, and control the gear system, brake, and the like. Further, the other ECU 21 is connected to the console 5 provided with various indicators, performs various controls in response to the driver's instruction, and presents the state to the driver.

These are limited examples, and the control by the ECU is wide-ranging. Further, the connection between each ECU and each device is only an example. For example, the lacquer ECU 11 may read the state of the ignition switch 3 directly via the dedicated bus 33 without going through the ECU 13 and the general-purpose bus 31. It can be lacquered or connected directly to the switch 3.

The park lock 7 is a mechanism that is usually independent of the side brake or other brakes equivalent and is configured to lock any shaft of the gear system so that the gear selector enters the park position. Works in conjunction with. In this specification and the accompanying claims, the phrase "locking the park lock" is used as defined to mean that the park lock enters a state in which the shaft is locked.

The park lock 7 comprises, for example, a notched wheel or parking gear on a shaft, a movable claw that locks the wheel, and an actuator for driving the claw. Instead of the combination of the wheel or gear and the claw, an appropriate latch mechanism or ratchet mechanism may be used. The actuator consists of, for example, a combination of an electric motor and a cam mechanism, but may be replaced with another drive mechanism such as a hydraulic cylinder mechanism or a gear mechanism.

For example, the transmission may include a park lock 7, or other gear mechanisms in the gear system may include a park lock 7. Also, one vehicle may be equipped with a plurality of park locks.

For example, a mechanical switch or a contact type or non-contact type sensor for detecting the physical position of the target can be adopted as the detection means 9, and when the park lock 7 is a mechanism by a claw, the switch or the sensor is a claw. Detect the position. The park lock ECU 11 detects whether or not the park lock is locked by being electrically connected to such a switch or sensor. Alternatively, the detection means 9 may be a sensor that reads the current or voltage applied to the actuator. In that case, the detection means 9 can be installed not only in the transmission but also outside the transmission, and in particular, the ECU 11 detects it. Means 9 can be included. Further, or instead of directly detecting, the ECU 11 takes in the states of a plurality of switches or sensors and / or actuators as variables, and determines whether or not the park lock 7 is locked by the combination of the plurality of variables. You may estimate.

With reference to FIG. 2 in combination with FIG. 1, when the park lock ECU 11 locks the park lock 7, control is performed as follows.

The park lock ECU 11 reads the state of the park lock 7 (for example, lock or unlock) and the state of the power supply (for example, on if the voltage is high, off if the voltage is low) via a sensor, and communicates with other ECUs. It repeats constantly. The information to be communicated includes various requests such as a park lock request and a shutdown request, and further includes a park lock completion notification.

The state of the park lock 7 read or estimated by the detecting means 9 is stored in, for example, the Act Position variable. The park lock completion notification is stored as a flag in the Park Position variable, for example, and is transmitted from the ECU 11 to another ECU as a notification via communication and used there.

Requests to the ECU 11 (eg, park lock, shutdown, etc.) are stored in the Request variable. The park lock request and the release request are not limited to those received by the ECU 11 from other devices, and may be stored as a request variable by the ECU 11's own judgment from a combination of state variables of a switch or a sensor, an actuator, and another device. Good. The state of the power supply is stored in the Power Off variable (for example, on if 0, off if 1) by the ECU 11 making a judgment (on if the voltage is high, off if the voltage is low) based on the value of the applied power supply voltage. Alternatively, the value of the Power Off variable may be acquired from another ECU by communication.

The ECU 11 determines whether the power is on (Power Off variable is 0), and if the power is on, then determines whether there is a park lock request (Request variable is Park). When there is a park lock request, the ECU 11 determines the state of the park lock 7, and when it is locked (the Act Position variable is Park), it does not control the park lock 7 (already locked). Has been). If the park lock 7 is not locked (the Act Position variable is not Park), the control to lock the park lock 7 is performed.

The control for locking the park lock 7 is illustrated in FIG. That is, in order to lock the park lock 7, the ECU 11 applies a current to the actuator to drive it. Next, the ECU 11 determines whether the park lock 7 is locked by using the detecting means 9, and if it is not locked, the current application to the actuator is repeated. If it confirms that it has been locked, control is reinstated.

Returning to FIG. 2, if the determination as to whether or not there is a park lock request is No, the ECU 11 can determine again whether or not there is a request to release the park lock (the Request variable is not Park). .. When there is a request to release the park lock, the ECU 11 determines the state of the park lock 7, and when it is not locked (the Act Position variable is not Park), no action is taken on the park lock 7. , When the park lock 7 is locked (Act Position variable is Park), the lock of the park lock 7 is controlled to be released.

Alternatively, the control at this time can be modified as shown in FIG. That is, in addition to determining whether there is a request to release the park lock (the Request variable is not Park), the ECU 11 again determines whether there is a park lock completion notification (the value of the Park Position variable is 1), and both of them are determined. If it is positive (Yes in the figure), then the ECU 11 determines the state of the park lock 7, and if it is not locked (the Act Position variable is not Park), it controls nothing for the park lock 7. Although it is not performed, when the park lock 7 is locked (the Act Position variable is Park), the lock release of the park lock 7 is controlled. On the other hand, if there is no request to release the park lock or there is no notification of the completion of the park lock, the ECU 11 returns the control to the park lock 7 without taking any action.

The control for unlocking the park lock 7 is illustrated in FIG. That is, in order to unlock the park lock 7, the ECU 11 applies a current to the actuator to drive it. Next, the ECU 11 determines whether the park lock 7 has been unlocked by using the detection means 9, and if it is not unlocked, the current application to the actuator is repeated. If it confirms that it has been unlocked, control is reinstated.

Returning to FIG. 2, when the ECU 11 determines that the power is off (Power Off variable is 1), whether there is a park lock request and whether the park lock 7 is locked in the same manner as described above. Based on somehow, the park lock 7 is controlled. In this case, if there is no park lock request, the ECU 11 returns the control to the park lock 7 without taking any action. When there is a park lock request, following the control of the park lock 7, a flag, for example 1, is set in the Park Position variable to restore the control. As already described, this variable is shared with other ECUs by communication and is therefore used to notify the other ECUs of the completion of park lock.

With reference to FIG. 6, another ECU (for example, ECU 13) or two or more other ECUs that control the shutdown operation shuts down each ECU as follows.

The ECU also reads the state (on or off) of the ignition switch 3 via a sensor, and constantly repeats communication with other ECUs. The state of the ignition switch is stored in, for example, an IGN variable. The park lock completion notification is stored as a flag in the Park Position variable, for example, and the ECU has acquired this in advance by communication, for example.

The ECU determines whether or not the ignition switch 3 is off, and if it is not off (the IGN variable is not Off), the Power Off variable is set to 0 and the control is restored. This is shared with the ECU 11 by communication and is used for the control by the ECU 11 already described. Alternatively, as already described, the ECU 11 can directly read the state of the ignition switch 3. When the ignition switch 3 is off (IGN variable is Off), the Power Off variable is set to 1, and then it is determined whether or not the shutdown condition is satisfied (the process surrounded by the alternate long and short dash line in FIG. 6).

Whether or not the shutdown condition is satisfied can be most simply determined by whether or not there is a shutdown request (Request variable is Shutdown). If the shutdown condition is not met, control is restored without doing anything. That is, the vehicle 1 is continuously maintained in an operable state. When the shutdown condition is satisfied, the control shifts to park lock and shutdown control as described later.

Whether or not the shutdown condition is satisfied can be modified as shown in FIG. 7A. That is, it is first determined whether or not the CAN communication is malfunctioning (Fail), and it is determined whether or not there is a shutdown request only when it is not a File. In the case of File, the control shifts to park lock and shutdown regardless of whether or not there is a shutdown request.

Alternatively, in any of the above examples, instead of determining whether or not there is a shutdown request, it may be determined whether or not the vehicle 1 is stopped. See FIG. 7B as a modification of FIG. 7A. The vehicle speed is stored in the Vehicle Speed variable, and the position of the gear selector (for example, P in the case of the park position) is stored in the Shift Position variable, which is shared with other ECUs by communication. For example, if the vehicle speed is less than a certain threshold value (Xkph), the gear selector is in the park position, or any of the conditions is satisfied, it can be determined that the vehicle 1 is stopped, and the shutdown condition is satisfied. It can be judged that it has been done. According to such a modification, even if a request is erroneously received from another ECU, the ECU 11 can autonomously determine the shutdown condition without being affected by the request.

With reference to FIG. 6, when the shutdown condition is satisfied, the control shifts to the park lock and the shutdown according to any of the above examples. That is, first, the ECU 13 determines whether or not the ECU 11 has completed the park lock based on the Park Position variable shared by communication. When it is completed (Park Position variable is 1), the ECU 13 shifts to the shutdown control.

If the ECU 13 cannot confirm the completion of the park lock, it issues a park lock request to the ECU 11 to execute the park lock. That is, for example, the Request variable is set to Park and CAN communication is executed. According to the process already described, the ECU 11 locks the park lock 7 and responds that the park lock is completed (Park Position variable is 1). The ECU 13 determines whether or not the park lock is completed, and repeats the CAN communication until the completion. When the park lock is completed (Park Position variable is 1), the ECU 13 clears the request.

In the shutdown control, the ECU 11 normally clears each variable (for example, the Park Position variable and the Power Off variable) and executes the shutdown.

As understood from the above, the ECU 11 autonomously determines to lock the park lock 7 without depending on the shutdown request transmitted from another ECU. Even if another ECU mistakenly sends a shutdown request or CAN communication fails, the vehicle is surely parked without being affected by them. Also, since such control inevitably precedes shutdown, the parked vehicle does not unintentionally start moving, as in the prior art. Since such control is performed exclusively using information that can be received by ordinary CAN communication, no additional information or device is required, and thus the above device or method is replaced with the conventional device or method as is. Can be done. In addition, when there is a park lock request, the park lock is surely performed, otherwise the park lock is not performed, and even if it is accidentally locked, it is surely released, which may hinder the operation of the vehicle. Absent.

Although some embodiments have been described, it is possible to modify or modify the embodiments based on the above disclosure contents.

An electronic control device and a control method for autonomously executing a park lock regardless of a communication malfunction are provided.

Claims (8)

An electronic control device that controls the park lock by being connected to the power supply of the vehicle and one or more other electronic control devices to share information via communication.
A locking means that locks the park lock if it detects that the power is turned off, the information includes a park lock request, and the park lock is not locked.
If it is detected that the park lock is locked, the park lock detection means that includes the park lock completion notification in the information, and
Electronic control device equipped with. A second locking means that locks the park lock if it detects that the power supply is not turned off, the information includes the park lock request, and the park lock is not locked.
The electronic control device according to claim 1, further comprising. A release means for releasing the park lock if it is detected that the power supply is not turned off, the information does not include the park lock request, and the park lock is locked.
The electronic control device according to claim 1 or 2, further comprising. A release means for releasing the park lock if the information includes a request to release the park lock and it is detected that the park lock is locked.
The electronic control device according to claim 1 or 2, further comprising. The park lock, which is executed by an electronic controller that detects the state of the vehicle's power supply and park lock and shares information, including at least one request, with one or more other electronic controllers by communication. It ’s a way to control
If it is detected that the power is turned off and the information includes a park lock request and the park lock is not locked, the park lock is locked.
Detects whether the park lock is locked,
How to include that. When the power supply is not turned off and the information includes the park lock request, the park lock is locked if it is detected that the park lock is not locked.
The method of claim 5, further comprising the above. If it is detected that the power supply is not turned off, the information does not include the park lock request, and the park lock is locked, the park lock is released.
The method of claim 5 or 6, further comprising: If it is detected that the information includes a request to release the park lock and the park lock is locked, the park lock is released.
The method of claim 5 or 6, further comprising:

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