JP2010255372A - Battery-degradation reporting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To more surely inform a decrease in battery voltage of a portable machine to a user. <P>SOLUTION: A battery-degradation reporting device informs the decrease in the battery voltage of the portable machine to the user. A smart key system 1, which configures a process where the user before getting on a vehicle till getting off the vehicle as one sequence, executes at least four portable-machine authentication processings containing: a portable-machine-authentication processing in communicating with the portable machine 40 outside the vehicle in a parking state; a portable-machine authentication processing in communicating with the portable machine inside the vehicle after a door lock is released; a portable-machine authentication processing in communicating with the portable-machine inside the vehicle when an engine or a vehicle power source is turned off; and a portable-machine authentication processing in communicating with the portable machine outside the vehicle when locking the door is instructed. When the battery degradation reporting device detects the battery-decrease in the portable machine based on a battery state signal received during each of the four portable machine authentication processing, information on the decrease in the batery for representing the battery degradation in the portable machine is visually outputted. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a battery low notification device that notifies a user of a battery low in a portable device.

  In recent years, two-way communication is performed by weak radio waves between a transmission / reception device mounted on a vehicle and a portable device (key), and an approach of a legitimate user to the vehicle is detected by confirming the ID code of the portable device. A smart key system for releasing the door lock of the vehicle simultaneously with the detection of the operation of the door outer handle has been put into practical use. In this smart key system, communication is performed even when the user is seated in the driver's seat after opening and closing the door, and the steering lock is unlocked by confirming the valid ID code of the portable device. Thereafter, the user can manually operate the engine push switch or the like to turn on the ignition switch and start the engine. Furthermore, in this smart key system, communication is also performed when the user turns off the ignition switch and leaves the vehicle after opening and closing the door, and by detecting the separation of the portable device having a valid ID code, the various devices described above can be detected. Set to locked state. As described above, in the smart key system, if the user has a portable device, various operations by the portable device are unnecessary, and convenience is achieved.

  In such a smart key system, when the power of the battery of the portable device is reduced, the remaining power of the battery of the portable device is predetermined in order to make the user surely recognize the necessity of battery replacement. When it is detected that the value is equal to or less than the threshold value, a technique is known in which the operation of the operating device by the operating device control unit is stopped or the transition to the operable state is stopped (for example, see Patent Document 1). This technology strongly impresses the user that the battery will run out in the near future by suspending the operating device before the battery built in the portable device runs out.

JP 2005-105657 A

  By the way, conventionally, as a technique for notifying the user of a decrease in the battery voltage of the portable device, battery voltage decrease information is transmitted from the portable device side to the vehicle side by wireless communication, and by a meter display or buzzer for a certain time on the vehicle side An alarming method was adopted. This system is configured to communicate with a portable device when a user turns off a vehicle power supply (ignition switch) in a boarding state, and to issue an alarm when battery voltage drop information is received.

  However, when the battery voltage drop information from the portable device is displayed on the vehicle side (for example, a meter), the user may not notice the display when getting on. When the user gets off the vehicle without noticing the display after all, the battery replacement of the portable device is delayed, and the number of cases where the smart key system cannot be used at the next boarding increases.

  Then, this invention aims at provision of the battery low notification apparatus which can notify a user more reliably of the fall of the battery voltage of a portable machine.

In order to achieve the above object, according to one aspect of the present invention, in the smart key system that executes portable device authentication processing for performing authentication of the portable device via wireless communication between the portable device and the vehicle side, A battery low notification device for notifying a user of a battery low of the machine,
The smart key system includes a portable device authentication process when communicating with a portable device outside the vehicle in a parked state, from the time before the user gets on board to the time after getting off, and the portable device in the vehicle interior after the door lock is released. Portable device authentication processing when communicating, portable device authentication processing when communicating with the portable device in the vehicle interior when the engine or vehicle power is turned off, and carrying outside the vehicle when instructed to lock the door lock Configured to perform at least four portable device authentication processes including a portable device authentication process when communicating with a machine,
In each of the at least four portable device authentication processes, the portable device detects a state of a battery mounted on the portable device, and displays a battery state signal indicating the detected battery state in the portable device authentication process. Configured to transmit to the vehicle side together with a response signal for
The battery low notification device represents a battery low of the portable device when the battery low of the portable device is detected based on the battery status signal received at each of the at least four portable device authentication processes. A battery low notification device is provided that visually outputs battery low information to a vehicle-side display or a portable device-side display.

  ADVANTAGE OF THE INVENTION According to this invention, the battery fall notification apparatus which can notify a user more reliably of the fall of the battery voltage of a portable device is obtained.

It is a figure which shows the principal part structure of the smart key system 1 relevant to the battery low notification apparatus by this invention. 3 is a diagram showing a main configuration of a key 40. FIG. It is a flowchart which shows an example of the response signal transmission process performed with the key 40 of a present Example. It is a figure which shows the output example of the battery low information in the indicator 46 of the key. 3 is a flowchart illustrating an example of battery low information notification processing executed by a smart ECU. It is a table | surface figure which shows the example of the actual operation | movement of 1 sequence. 7 is a flowchart illustrating another example of battery low information notification processing executed by the smart ECU.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram showing a main configuration of a smart key system 1 related to a battery low notification device according to the present invention.

  The battery low notification device is configured around a smart ECU 10 that controls the smart key system 1. The smart ECU 10 is configured as a microcomputer including a CPU, a ROM, a RAM, and the like that are connected to each other via a bus (not shown). Various programs executed by the CPU are stored in the ROM.

  The smart ECU 10 is connected to a vehicle exterior key detection transmitter 12 that forms a detection area for detecting the key (portable device) 40 outside the vehicle interior. The vehicle key detection transmitter 12 includes a vehicle key detection antenna 12a, and forms a detection region for detecting the key 40 by transmitting a request signal via the vehicle key detection antenna 12a. . A plurality of vehicle exterior key detection transmitters 12 and vehicle exterior key detection antennas 12a may be set. For example, the right and left side door exterior spaces and the front passenger side door exterior spaces of the vehicle One each may be built in the door outside handle.

  The smart ECU 10 is connected to a vehicle interior key detection transmitter 14 that forms a detection region for detecting the key 40 in the vehicle interior. The vehicle interior key detection transmitter 14 includes a vehicle interior key detection antenna 14a, and forms a detection region for detecting the key 40 by transmitting a request signal via the vehicle interior key detection antenna 14a. . A plurality of vehicle interior key detection transmitters 14 and vehicle interior key detection antennas 14a may be set, for example, a total of three corresponding to the front seat space, rear seat space, and luggage space of the vehicle. May be.

  The smart ECU 10 is connected to a receiver 18 that receives a response signal (transmitted radio wave) from the key 40. The receiver 18 is disposed at a position that can receive a response signal transmitted from the key 40 in the detection area of the vehicle interior key detection antenna 12a and the vehicle interior key detection antenna 14a. May be arranged. The receiver 18 may be additionally arranged in the luggage space, and the number and arrangement position thereof are arbitrary. When receiving the response signal from the key 40, the receiver 18 performs predetermined processing such as amplification and demodulation on the response signal received from the key 40, and then supplies the demodulated response signal to the smart ECU 10. The smart ECU 10 compares the encryption code included in the received response signal with the encryption code stored in a predetermined memory (not shown), and if they match, the smart ECU 10 is the regular key 40. Authentication result (authentication result to the effect that key authentication has been obtained) is output.

  The smart ECU 10 is connected to a body ECU 32, an engine ECU 35, a meter ECU 36, a navigation ECU 38, and the like via a bidirectional multiplex communication line 30 such as a CAN (controller area network). The smart ECU 10 is connected to a lock switch 22 that is turned on / off in response to a lock operation for locking the door. A door lock actuator 34 that drives a door lock mechanism is connected to the body ECU 32. The body ECU 32 is connected to a touch sensor 24 for detecting a touch operation on the door outside handle. The lock switch 22 and the touch sensor 24 may be provided near the door outside handle, and the touch sensor 24 may be arranged to detect a touch operation on the back side of the door outside handle. The door lock actuator 34 switches the door lock mechanism between the door locked state and the door unlocked state in accordance with a control signal from the body ECU 32. An engine (not shown) or the like is connected to the engine ECU 35. The engine ECU 35 is connected to an engine switch 26 operated by a user to start the engine. The engine switch 26 may be disposed near the steering column of the instrument panel, for example. A display 37 installed in the meter is connected to the meter ECU 36. The display 37 displays battery lowering information (notification) described later. A speaker 39 is connected to the navigation ECU 38. From the speaker 39, in addition to outputting normal music, guidance messages, and the like, battery low information (notification) described later is output.

  The smart ECU 10 communicates with the key 40 in the vehicle interior after the door lock is released, with the first key authentication process when communicating with the key 40 outside the vehicle in the parked state, as a sequence from before the user gets on to after getting off the vehicle. The second key authentication process when the engine is turned off, the third key authentication process when communicating with the key 40 in the vehicle interior when the engine is turned off or the IG power is turned off, and the vehicle when the door lock is instructed It is configured to perform at least four portable device authentication processes including a fourth key authentication process when communicating with the external key 40.

  The first key authentication process is executed in a parking state where no user is present in the passenger compartment. In this parking state, a request signal is periodically transmitted from the vehicle interior key detection transmitter 12 to form a detection area for detecting the key 40 outside the vehicle interior. When the key 40 enters the detection area, a response signal is transmitted from the key 40. The first key authentication process is started when the response signal from the key 40 is received by the receiver 18.

  When the encryption codes match in the first key authentication process, the smart ECU 10 supplies the fact (authentication result that the key authentication has been obtained) to the body ECU 32. When the body ECU 32 receives a touch operation detection signal from the touch sensor 24 within a predetermined time after receiving the authentication result, the body ECU 32 drives the door lock actuator 34 to switch the door lock mechanism to the door unlock state.

  The second key authentication process is executed after the first key authentication process. Specifically, it is executed in a state where the user opens the door of the vehicle and gets into the vehicle interior. For example, when the door unlock state is formed by the first key authentication process, and then the door opening is detected by the door switch (or when the depression of the brake is detected), the vehicle interior key detection transmitter 14 A request signal is transmitted, and a detection area for detecting the key 40 is formed in the passenger compartment. When the key 40 exists in this detection area, a response signal is transmitted from the key 40. The second key authentication process is started when the response signal from the key 40 is received by the receiver 18.

  If the encryption codes match in the second key authentication process, the smart ECU 10 supplies that fact (authentication result that the key authentication has been made) to the engine switch 26. When the engine switch 26 receives a push operation signal from the engine switch 26 within a predetermined time after receiving the authentication result, the engine switch 26 starts an engine (not shown). In addition, when key authentication is obtained in the second key authentication process or the first key authentication process described above, for example, release of the immobilizer function (for example, unlocking of the steering lock) may be realized.

  The third key authentication process is executed after the second key authentication process. Specifically, it is executed when the user starts the engine, typically drives the vehicle, arrives at the destination, and stops the engine. Specifically, when engine operation is stopped (or after that, when the brake is depressed), a request signal is transmitted from the vehicle interior key detection transmitter 14 to detect the key 40 in the vehicle interior. A detection area is formed for this purpose. When the key 40 exists in this detection area, a response signal is transmitted from the key 40. The third key authentication process is started when the response signal from the key 40 is received by the receiver 18.

  When the encryption code matches in the third key authentication process, the smart ECU 10 supplies that fact (an authentication result indicating that the key authentication has been obtained) to the engine switch 26. When the engine switch 26 receives a push operation signal from the engine switch 26 within a predetermined time after receiving the authentication result, the engine switch 26 starts the engine. As described above, the third key authentication process assumes that the engine is temporarily stopped, but the engine is restarted immediately after noticing that the user forgot to close the window, for example.

  The fourth key authentication process is executed after the third key authentication process. Specifically, the user stops the engine, opens the door, goes out of the vehicle, closes the door, and operates the lock switch 22. When the operation signal of the lock switch 22 is received, a request signal is transmitted by the vehicle exterior key detection transmitter 12 to form a detection region for detecting the key 40 outside the vehicle interior. When the key 40 exists in this detection area, a response signal is transmitted from the key 40. The fourth key authentication process is started when the response signal from the key 40 is received by the receiver 18.

  When the encryption codes match in the fourth key authentication process, the smart ECU 10 supplies the body ECU 32 with information indicating that the key 40 has been locked while being outside the vehicle compartment. When receiving the information from the smart ECU 10, the body ECU 32 drives the door lock actuator 34 to switch the door lock mechanism to the door lock state. From the viewpoint of preventing key confinement, when an operation signal of the lock switch 22 is received, a detection area for detecting the key 40 is formed in the vehicle interior by the vehicle interior key detection transmitter 14. If the user leaves the vehicle and operates the lock switch 22 with the key 40 left in the vehicle interior, a response signal from the key 40 corresponding to the request signal from the vehicle interior key detection transmitter 14 is received by the receiver. 18 is received. Although the authentication process is also performed at this time, the fourth key authentication process may include such an authentication process for preventing key confinement.

  FIG. 2 is a diagram illustrating a main configuration of the key 40. The key 40 may be a key with a built-in mechanical key including a mechanical key that can lock and unlock the door of the vehicle by a user operation. Alternatively, the key 40 may be a key independent of the mechanical key.

  The key 40 includes a transmitting / receiving unit 42 that performs bidirectional communication with a transmitting / receiving antenna 41 and a transmitter / receiver on the vehicle side (elements 12, 14, 18, etc.) using weak radio waves, a portable device battery 43, and a control device 44. And a display 46.

  The display 46 may be formed of, for example, electronic paper with low power consumption. The display 46 outputs a battery low information output unit 46a that outputs battery low information, which will be described later, and normal information that outputs information other than the battery low information (for example, date and time or a pictorial display indicating that radio waves are being transmitted). And an output unit 46b. The power supply voltage supply line from the portable device battery 43 to the display 46 includes a first power supply voltage supply line 47 connected to the battery lowering information output unit 46a and a second power supply voltage supply connected to the normal information output unit 46b. Branch to line 49. The second power supply voltage supply line 49 is provided with a switch 48, and only the normal information output unit 46b can be disconnected (blocked) from the portable device battery 43. Opening and closing of the switch 48 on the second power supply voltage supply line 49 is controlled by the control device 44 and is closed in a normal state.

  The control device 44 may be configured by an IC. The control device 44 implements communication control via the transmission / reception unit 42 and display control via the display 46. The control device 44 has a function of measuring the voltage (battery voltage) of the portable device battery 43. The control device 44 also includes a memory that stores a given valid encryption code (ID code).

  FIG. 3 is a flowchart illustrating an example of a response signal transmission process executed by the key 40 of the present embodiment.

  In step 300, the key 40 receives the request signal transmitted through the vehicle interior key detecting antenna 12a as described above by the transmission / reception antenna 41. The received signal is demodulated by the transmitter / receiver 42 and supplied to the controller 44.

  In step 302, the control device 44 of the key 40 measures the battery voltage of the portable device battery 43. The battery voltage is preferably measured in conjunction with the reception of the request signal, but may be measured periodically. In this case, the control device 44 uses the latest measurement result of the battery voltage of the portable device battery 43.

  In step 304, the control device 44 of the key 40 generates a battery state signal representing the measurement result of the battery voltage of the portable device battery 43. The battery state signal represents at least two types of states, ie, a confirmed lowering state in which the battery voltage is lowered and a lowering state in which the battery voltage is being lowered, according to the measurement result of the battery voltage of the portable device battery 43. Generated. In this example, the battery state signal is generated in accordance with the measurement result of the battery voltage of the portable device battery 43 so as to represent a normal state in which the battery voltage is normal, a decrease confirmed state, and two types of lowering states. The Specifically, when the measurement result of the battery voltage of the portable device battery 43 is 2.3 V or more, a battery state signal indicating a normal state is generated, and the measurement result of the battery voltage of the portable device battery 43 is 2.2 V. When the voltage is less than 2.3 V, a battery state signal indicating the first stage of a lowering state is generated, and when the measurement result of the battery voltage of the portable device battery 43 is 2.1 V or more and less than 2.2 V, A battery state signal representing the state of the second stage of lowering in the second stage is generated, and when the result of measuring the battery voltage of the portable device battery 43 is less than 2.1 V, a battery state signal representing the lowering confirmed state is generated. Here, as an example, as shown in Table 1, the battery state signal is composed of 2 bits, the battery state signal indicating the normal state, the battery state signal indicating the lowering state of the first stage, and the lowering of the second stage. The battery state signal indicating the state and the battery state signal indicating the decrease confirmed state are set to “00”, “01”, “10” and “11”, respectively.

ステップ３０６では、キー４０の送受信部４２は、電池状態信号を応答信号に組み込み、当該応答信号を送受信アンテナ４１により送信する。尚、この応答信号には、電池状態信号のコード及び暗号コードと共に、車室外キー検知用アンテナ１２ａに対する応答であることを表すコードが、組み込まれる。また、キー４０は、上述の如く車室内キー検知用アンテナ１４ａを介して送信されるリクエスト信号を受信したとき、当該リクエスト信号に応じた応答信号を送信する。この応答信号には、電池状態信号のコード及び暗号コードと共に、車室内キー検知用アンテナ１４ａに対する応答であることを表すコードが、組み込まれる。このようにして、キー４０は、車室外キー検知用アンテナ１２ａを介して送信されるリクエスト信号を受信したときと、上述の如く車室内キー検知用アンテナ１４ａを介して送信されるリクエスト信号を受信したときとで、異なる応答信号を送信するように構成される。これにより、スマートＥＣＵ１０は、キー４０からの応答信号を解読することで、キー４０が車室内に存在するか車室外に存在するかを把握することができる。

In step 306, the transmission / reception unit 42 of the key 40 incorporates the battery state signal into the response signal, and transmits the response signal by the transmission / reception antenna 41. The response signal includes a battery status signal code and an encryption code, as well as a code indicating that the response is to the vehicle key detection antenna 12a. Further, when the key 40 receives a request signal transmitted via the vehicle interior key detecting antenna 14a as described above, the key 40 transmits a response signal corresponding to the request signal. In this response signal, a code indicating a response to the vehicle interior key detecting antenna 14a is incorporated together with the code of the battery state signal and the encryption code. Thus, the key 40 receives the request signal transmitted via the vehicle interior key detection antenna 12a and the request signal transmitted via the vehicle interior key detection antenna 14a as described above. It is configured to transmit different response signals depending on the time. Thereby, smart ECU10 can grasp | ascertain whether the key 40 exists in a vehicle interior or a vehicle interior by decoding the response signal from the key 40. FIG.

  In this way, the key 40 of this embodiment transmits a response signal including the battery state signal in each key authentication process of the one sequence described above. Therefore, the smart ECU 10 can sequentially grasp the battery voltage (battery state) of the key 40 in each key authentication process of the above-described one sequence. That is, in the above-described one sequence, there is an opportunity to grasp the battery voltage of the key 40 four times. Therefore, even if the battery voltage decreases and a situation that should be notified to the user occurs, the situation is accurately detected and the user is detected. Can be notified.

  Note that, as the simplest notification mode, the smart ECU 10 receives a battery state signal indicating a low battery state when receiving a battery state signal indicating a low state in the key authentication process in at least one of the above-described sequences. Command to output information (notification). The command may be transmitted to the meter ECU 36 and the navigation ECU 38, for example. In this case, the meter ECU 36 visually outputs the battery low information to the display 37, and the navigation ECU 38 acoustically outputs the battery low information via the speaker 39. For example, the meter ECU 36 may turn on an indicator that is scheduled to be turned on (known to the user) when the battery of the portable device battery 43 is low or the battery runs out. Moreover, navigation ECU38 may output the message which tells directly the battery low of a portable machine battery 43, or a battery exhaustion.

  Alternatively, the smart ECU 10 may transmit a similar command to the key 40 by wireless communication. In this case, the control device 44 of the key 40 visually outputs the battery low information via the battery low information output unit 46a of the display 46. For example, as shown in FIG. 4 as an example, the control device 44 will “change the key battery” or “the key battery will soon expire, via the battery low information output unit 46a of the display 46. You may output a message stating that “Start the engine by touching the engine switch with the key.” Further, the control device 44 preferably opens the switch 48 (see FIG. 2) in order to eliminate power consumption for other displays when outputting the battery low information as described above. As a result, the normal information output unit 46b (see FIG. 2) is disconnected from the portable device battery 43, power consumption for other displays is eliminated, and battery low information can be efficiently output even in a low battery state. .

  Next, a more preferable notification mode of battery low information will be described with reference to FIGS. 5 and 6.

  FIG. 5 is a flowchart illustrating an example of battery low information notification processing executed by the smart ECU 10. The notification process shown in FIG. 5 is executed for each sequence described above.

  In step 500, the smart ECU 10 executes a first key authentication process.

  In step 501, the smart ECU 10 determines whether or not a battery state signal indicating a confirmed decrease state has been received from the key 40 during the first key authentication process in step 500. If a battery state signal representing a confirmed decrease state is received, the process proceeds to step 502. If a battery state signal representing a state other than the confirmed decrease state is received, the process proceeds to step 504.

  In step 502, the smart ECU 10 commands to output battery low information for notifying battery low. As described above, this command may be transmitted to the meter ECU 36 or the navigation ECU 38 and / or may be transmitted to the key 40 by wireless communication.

  In step 503, the smart ECU 10 sets the flag to “1” when the current flag is “0”, and maintains the flag at “1” when the current flag is “1”. Here, when this flag is “1”, it indicates that a battery state signal indicating a lower confirmed state has been received, and when this flag is “0”, a battery state signal indicating a lower confirmed state has been received. It means not. It is assumed that the flag is initialized (zero) at the start of the processing shown in FIG. When the processing of step 503 is completed, the routine proceeds to step 504.

  In step 504, the smart ECU 10 stands by until the next key authentication process. For example, if the previous key authentication process is the first key authentication process, the second key authentication process is awaited. If the previous key authentication process is the second key authentication process, the third key authentication process is performed. Waiting to be executed.

  In step 505, the smart ECU 10 executes the following key authentication process. For example, when the previous key authentication process is the first key authentication process, the smart ECU 10 normally executes the second key authentication process as the next key authentication process. In the normal flow, the second key authentication process should be executed as the next key authentication process. For example, when the first key authentication process is executed (for example, when the user once approaches the vehicle If the user leaves the vehicle and approaches the vehicle again), the process may return to step 500.

  In step 506, the smart ECU 10 determines whether or not a battery state signal indicating a confirmed decrease state has been received from the key 40 during the key authentication process in step 505. If a battery state signal indicating a confirmed decrease state is received, the process proceeds to step 502, and if a battery state signal indicating a state other than the confirmed decrease state is received, the process proceeds to step 507.

  In step 507, the smart ECU 10 determines whether or not a battery state signal indicating a state of lowering is received from the key 40 during the key authentication process in step 505. If a battery state signal representing a state of lowering is received, the process proceeds to step 508, and if a battery state signal representing a state other than the confirmed state of lowering and the state of lowering (that is, a normal state) is received, the process proceeds to step 509.

  In step 508, the smart ECU 10 determines whether or not the flag is 1. If the flag is 1, the process proceeds to step 502. Accordingly, when a battery state signal indicating a confirmed decrease state is received during one sequence, battery decrease information is output even when a battery state signal indicating a state of lowering is received thereafter. On the other hand, if the flag is not 1, the process proceeds to step 509. That is, the battery low information is not output only when the battery state signal representing the state of being lowered is received. This is because even if the battery voltage of the portable device battery 43 is temporarily lowered, it may be restored to a normal region depending on the subsequent use state.

  In step 509, the smart ECU 10 determines whether or not the fourth key authentication process (the last key authentication process in one sequence) has been completed. When the execution of the fourth key authentication process is completed, one sequence is completed. Therefore, the process is ended as it is, and the execution of the fourth key authentication process is not completed yet (for example, the second key authentication process or the third key authentication process). If the key authentication process has been completed, the process returns to step 504.

  In the battery low information notification process shown in FIG. 5, for example, as shown in FIG. 6, a battery state signal representing a low confirmed state (“11”) is received during the second key authentication process in one sequence, and the battery low information is displayed. Is notified to the user. Further, during the subsequent third and fourth key authentication processing, a battery state signal indicating a state of being lowered (“01”) is received, and the battery low information is notified to the user each time.

  As described above, according to the battery low information notification process shown in FIG. 5, when a battery state signal representing a confirmed decrease state is received during one sequence, a battery state signal representing a state of lowering is received thereafter. Even in this case, since the battery low information is output, the chance of notifying the user increases and the certainty increases. Accordingly, even when the battery voltage is restored while traveling, for example, after receiving the battery state signal indicating the state of lowering, the battery lowering information is notified to the user as long as the battery is in the state of lowering. This is because such a revival of the battery voltage is temporary, and it is predicted that the battery voltage will soon fall into a confirmed state of decrease. Therefore, it is effective to increase the number of notifications. On the other hand, since battery low information is not output only when a battery state signal representing a state of lowering is received, useless battery lowering information can be prevented from being output when battery replacement is not necessary. In addition, since the battery state is determined four times during one sequence using the existing smart communication opportunity, it is possible to accurately detect the low battery state to be notified to the user, and the opportunity to notify the user Increases certainty. In addition, since there is a possibility of being notified a plurality of times during one sequence, it is possible to increase the alert to the user.

  FIG. 7 is a flowchart illustrating another example of the battery low information notification process executed by the smart ECU 10. The notification process shown in FIG. 7 is executed for each sequence described above.

  In step 700, the smart ECU 10 initializes the flag based on the battery state history in the previous sequence prior to the execution of the first key authentication process. Specifically, if a battery state signal indicating a lower confirmed state (“11”) has been received during the previous sequence, the flag is set to “1”. On the other hand, if the battery state signal indicating the lower confirmed state (“11”) has not been received during the previous sequence, the flag is set to “0”.

  In step 701, the smart ECU 10 executes a first key authentication process.

  In step 702, the smart ECU 10 determines whether or not a battery state signal indicating a confirmed decrease state has been received from the key 40 during the first key authentication process in step 701. If a battery state signal indicating a confirmed decrease state is received, the process proceeds to step 703. If a battery state signal indicating a state other than the confirmed decrease state is received, the process proceeds to step 705.

  In step 703, the smart ECU 10 instructs to output battery low information for informing the battery low. This command may be transmitted to the meter ECU 36 or the navigation ECU 38 and / or may be transmitted to the key 40 as described above.

  In step 704, the smart ECU 10 sets the flag to “1” when the current flag is “0”, and maintains the flag at “1” when the current flag is “1”.

  In step 705, it is determined whether or not a battery state signal representing a state of lowering is received from the key 40 during the key authentication process in step 701. When the battery state signal indicating the state of lowering is received, the process proceeds to step 706, and when the battery state signal indicating the state other than the confirmed state of lowering and the state of lowering (that is, normal state) is received, the process proceeds to step 707.

  In step 706, the smart ECU 10 determines whether or not the flag is 1. If the flag is 1, the process proceeds to step 703. Therefore, if a battery state signal indicating a confirmed decrease state was received during the previous sequence, a battery indicating a state that is in the process of being lowered even if a battery state signal indicating the confirmed decrease state is not received during the current sequence. When the status signal is received, the battery low information is output. On the other hand, if the flag is not 1, the process proceeds to step 707.

  In step 707, the smart ECU 10 stands by until the next key authentication process. For example, if the previous key authentication process is the first key authentication process, the second key authentication process is awaited. If the previous key authentication process is the second key authentication process, the third key authentication process is performed. Waiting to be executed.

  In step 708, the smart ECU 10 executes the following key authentication process. For example, when the previous key authentication process is the first key authentication process, the smart ECU 10 normally executes the second key authentication process as the next key authentication process. In addition, for example, when the first key authentication process is executed in a situation where the second key authentication process should be executed as the next key authentication process in a normal flow (for example, a user who gets close to the vehicle once gets into the vehicle) If the user leaves the vehicle and approaches the vehicle again), the process may return to step 701.

  In step 709, the smart ECU 10 determines whether or not a battery state signal indicating a confirmed decrease state has been received from the key 40 during the key authentication process in step 708. If a battery state signal indicating a confirmed decrease state is received, the process proceeds to step 703, and if a battery state signal indicating a state other than the confirmed decrease state is received, the process proceeds to step 710.

  In step 710, the smart ECU 10 determines whether or not a battery state signal indicating a state of lowering is received from the key 40 during the key authentication process in step 708. If a battery state signal indicating a state of lowering is received, the process proceeds to step 711, and if a battery state signal indicating a state other than the confirmed state of lowering and the state of lowering (that is, a normal state) is received, the process proceeds to step 712.

  In step 711, the smart ECU 10 determines whether or not the flag is 1. If the flag is 1, the process proceeds to step 703. Accordingly, when a battery state signal indicating a confirmed decrease state is received during the current sequence or the previous sequence, the battery decrease information is output even when a battery state signal indicating a state of lowering is received thereafter. Become. On the other hand, if the flag is not 1, the process proceeds to step 712. That is, in a situation where a battery state signal representing a state of lowering is not received, battery lowering information is not output only when a battery state signal representing a state of lowering is received. This is because even if the battery voltage of the portable device battery 43 is temporarily lowered, it may be restored to a normal region depending on the subsequent use state.

  In step 712, the smart ECU 10 determines whether or not the fourth key authentication process (the last key authentication process in one sequence) has been completed. When the execution of the fourth key authentication process is completed, the process proceeds to step 713. On the other hand, if the fourth key authentication process has not yet been completed (for example, if the second key authentication process or the third key authentication process has only been completed), the process returns to step 707.

  In step 713, the smart ECU 10 stores and holds the battery state history in the current sequence in a predetermined nonvolatile memory, and the process ends. The battery state history thus saved is used in the flag initialization process (see step 700) of the next sequence. The battery state history may be a battery state history for four times obtained during each key authentication process in the sequence, or whether or not a battery state signal indicating a confirmed low state is received during the sequence. It may be information indicating. From the same viewpoint, the state of the flag may not be cleared at the end of one sequence (when the fourth key authentication process is completed) but may be retained. In this case, the value of the flag may be cleared only when the battery state signal indicating the decrease confirmed state is not received during the one sequence at the end of the one sequence. In such a configuration, the history of the battery state is substantially held in the flag value.

  According to the battery low information notification process shown in FIG. 7, in addition to the effects of the battery low information notification process shown in FIG. As described above, if a battery state signal indicating a confirmed decrease state is received during the previous sequence, the state indicating a decrease is indicated even if a battery state signal indicating the confirmed decrease state is not received during the current sequence. When the battery status signal is received, the battery low information is output, so that the chance of notifying the user is further increased and the certainty can be further increased.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, the battery low information is displayed on the meter display 37 on the vehicle side, but the battery low information is displayed on other in-vehicle displays (for example, a display or a head-up display on which a map of a navigation system is displayed). May be.

1 Smart Key System 10 Smart ECU
DESCRIPTION OF SYMBOLS 12 Outside key detection transmitter 12a Outside key detection antenna 14 Inside key detection transmitter 14a Inside key detection antenna 18 Receiver 22 Lock switch 24 Touch sensor 26 Engine switch 30 Two-way multiplex communication line 32 Body ECU
34 Door lock actuator 35 Engine ECU
36 Meter ECU
37 Display 38 Navigation ECU
39 Speaker 40 Key 41 Transmitting / receiving antenna 42 Transmitting / receiving unit 43 Portable battery 44 Control device 46 Display 46a Battery low information output unit 46b Normal information output unit 47 First power supply voltage supply line 48 Switch 49 Second power supply voltage supply line

Claims (4)

In a smart key system that executes portable device authentication processing for performing authentication of a portable device via wireless communication between the portable device and the vehicle side, a battery low notification device that notifies a user of a decrease in battery of the portable device. And
The smart key system includes a portable device authentication process when communicating with a portable device outside the vehicle in a parked state, from before the user gets on board to after the getting off, and a portable device in the vehicle interior after the door lock is released. Portable device authentication processing when communicating, portable device authentication processing when communicating with the portable device in the vehicle interior when the engine or vehicle power is turned off, and carrying outside the vehicle when instructed to lock the door lock Configured to perform at least four portable device authentication processes including a portable device authentication process when communicating with a machine,
In each of the at least four portable device authentication processes, the portable device detects a state of a battery mounted on the portable device, and displays a battery state signal indicating the detected battery state in the portable device authentication process. Configured to transmit to the vehicle side together with a response signal for
The battery low notification device represents a battery low of the portable device when the battery low of the portable device is detected based on the battery status signal received at each of the at least four portable device authentication processes. A battery low notification device characterized by visually outputting battery low information to a display on a vehicle side or a display on a portable device side. The battery state signal represents at least two types of states: a confirmed decrease state in which the battery voltage has decreased, and a state in the middle of a decrease in which the battery voltage is decreasing,
The battery low notification device receives the battery state signal representing the confirmed decrease state during the one sequence, and the portable device authentication process after receiving the battery state signal representing the confirmed decrease state The battery low notification device according to claim 1, wherein when a battery state signal indicating the state of lowering is received, a battery low of the portable device is detected and the battery low information is output.   The battery low notification device receives the battery state signal indicating the low confirmed state during the previous one sequence, and displays the low state during the arbitrary mobile device authentication processing in the current one sequence. The battery low notification device according to claim 2, wherein when a battery state signal to be expressed is received, a battery low of the portable device is detected and the battery low information is output. The battery low information is output to the display of the portable device,
The portable device has a power supply circuit separately including a first power supply voltage supply line for displaying the battery low information and a second power supply voltage supply line for displaying information other than the battery low information,
The battery low notification device according to claim 1, wherein the portable device shuts off the second power supply voltage supply line and outputs the battery low information using the first power supply voltage supply line.

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