JP2011184963A - Keyless entry system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a keyless entry system capable of preventing an unexpected locking operation of a door in connection with reduction in a remaining battery power in a mobile device. <P>SOLUTION: A vehicular control unit 12 controls locking for locking the door 1a of a vehicle when the state of receiving an answer signal from the mobile device 3 is shifted to the state of not receiving. The mobile device 3 includes a driving battery 25 and a measuring means 26 for detecting the residual battery power. When the measuring means 26 detects the residual battery power being equal to or less than a predetermined amount, a mobile device control unit 22 transmits the answer signal including information to that effect. The vehicular control unit 12 stops the locking control when receiving the answer signal including the information that the residual power of the battery 25 is equal to or less than the predetermined amount. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a keyless entry device that locks and unlocks a door of a vehicle by performing wireless communication between the vehicle side device and the portable device, and in particular, an unintended operation is performed when the battery of the portable device is consumed. It is related with the keyless entry device which can prevent.

  2. Description of the Related Art Conventionally, a keyless entry device that performs wireless communication between a vehicle-side device provided in a vehicle and a portable device carried by a user and locks / unlocks the door of the vehicle is known. In recent years, when a portable device approaches the vehicle, communication is automatically performed between the vehicle-side device and the portable device, and if the ID that is uniquely set for each portable device is authenticated, A passive keyless entry device that performs locking and unlocking operations is also known.

  The portable device operates using a battery as a power source. When the battery is depleted, the portable device will not operate. Therefore, when the remaining battery level in the portable device falls below a predetermined level, the portable device and the vehicle side device are notified, and then a request signal from the vehicle side device. Even when the mobile phone is received, an answer signal is not transmitted from the portable device, so that power consumption is reduced and the user is notified of a decrease in the remaining battery level. An example of such a keyless entry device is disclosed in Patent Document 1.

JP 2002-47839 A

  In a passive keyless entry device, a request signal is transmitted when a request switch provided on the vehicle is operated periodically or from the vehicle side device, and the portable device that receives the request signal transmits a predetermined answer signal, The vehicle-side device that has received the answer signal performs predetermined control such as unlocking the door. In the type that periodically sends a request signal, it is detected that the door is locked when the vehicle-side device receives an answer signal from the portable device and does not receive it under a predetermined condition. Is the time. This is based on the assumption that it is detected that the answer signal from the portable device does not reach the vehicle-side device when the user carries the portable device away from the vehicle.

  However, even when the remaining battery level of the portable device decreases, the vehicle-side device may change from a state in which an answer signal from the portable device is received to an unintended operation. When the portable device is left for a long time in a state where it can communicate with the vehicle-side device, an answer signal is continuously transmitted to the vehicle-side device, and the remaining battery level decreases. When the remaining battery level becomes equal to or lower than the predetermined value, the answer signal is not transmitted. Therefore, the vehicle-side device erroneously recognizes that the portable device has left the vehicle, and controls the door to be locked. As a result, the portable device may be confined in the vehicle.

  Concerning the confinement of the portable device in the vehicle, the door side is locked only when the vehicle side device recognizes that the portable device has transmitted an answer signal from the outside of the vehicle and no longer receives the answer signal from the portable device. If the aircraft continues to send an answer signal from inside the vehicle, it is conceivable that the door is not locked. As a means for recognizing that the portable device has transmitted the answer signal from the outside of the vehicle in the vehicle side device, a method of recognizing the transmission from the outside when the answer signal is received by the antenna installed outside the vehicle, A weight sensor is provided on the seat of the vehicle, and when an answer signal is received after the weight sensor detects the getting-off, a method of recognizing that the transmission is from the outside of the vehicle, or an answer signal is received after the door is opened and closed A method of recognizing that the transmission is from outside the vehicle can be considered.

  However, even if such measures are taken, if the portable device is left for a long time in a range where it can communicate with the vehicle-side device outside the vehicle, the remaining battery level of the portable device decreases and an answer signal is transmitted. When it disappears, the vehicle-side device erroneously recognizes that the portable device is away from the vehicle, and the door is locked, and an unintended operation is performed.

  The present invention has been made in view of the above problems, and an object thereof is to provide a keyless entry device that can prevent an unintended door locking operation from being performed in accordance with a decrease in the remaining battery level of a portable device. To do.

In order to solve the above-described problem, a keyless entry device according to the present invention includes a vehicle-side device that is provided in a vehicle and intermittently transmits a request signal and receives an answer signal, and a portable device that receives the request signal and transmits an answer signal. In a keyless entry device with a machine,
The vehicle-side device includes a vehicle-side control unit that performs predetermined control when an answer signal from the portable device is authenticated, and the vehicle-side control unit receives a response signal from the portable device and does not receive the answer signal. When it becomes, perform the locking control to lock the door of the vehicle,
The portable device receives a request signal transmitted from the vehicle side device and returns an answer signal when authentication is established, a battery for driving, and a measuring means for detecting the remaining amount of the battery Prepared,
When the portable device control unit detects that the remaining amount of the battery is equal to or less than a predetermined value or less than a predetermined value by the measurement unit, the portable device control unit transmits an answer signal including information to that effect,
The vehicle-side control unit is configured to stop the locking control when receiving an answer signal including information indicating that the remaining amount of the battery is equal to or less than a predetermined value or less than a predetermined value.

  Further, in the keyless entry device according to the present invention, after the vehicle-side control unit receives an answer signal including information indicating that the remaining amount of the battery is less than or less than a predetermined value, It is characterized by not transmitting a request signal.

Furthermore, the keyless entry device according to the present invention includes a vehicle-side device that is provided in a vehicle and intermittently transmits a request signal and receives an answer signal, and a portable device that receives the request signal and transmits the answer signal. In keyless entry device,
The vehicle-side device includes a vehicle-side control unit that performs predetermined control when an answer signal from the portable device is authenticated, and the vehicle-side control unit receives a response signal from the portable device and does not receive the answer signal. When it becomes, perform the locking control to lock the door of the vehicle,
The portable device includes a portable device control unit that transmits an answer signal when receiving a request signal transmitted from the vehicle-side device, and a battery for driving.
The portable device control unit transmits an answer signal including information according to the signal strength from the vehicle side device,
When the vehicle-side control unit is in a state of not receiving an answer signal from the portable device, the vehicle-side control unit records a signal history included in the received answer signal or a history of information corresponding to the signal strength of the answer signal. If the distance between the portable device corresponding to the signal strength and the vehicle side device is gradually increased, the locking control is performed, and the distance between the portable device corresponding to the signal strength and the vehicle side device is substantially constant. In some cases, the locking control is not performed.

  Furthermore, in the keyless entry device according to the present invention, the vehicle-side control unit is a signal included in the received answer signal when the vehicle-side control unit is in a state of not receiving from the state of receiving the answer signal from the portable device. When the signal strength is substantially constant according to the history of information corresponding to the strength, the request signal is not transmitted thereafter.

  In the keyless entry device according to the present invention, the vehicle-side control unit refers to the signal strength included in the received answer signal, or the history of information corresponding to the signal strength of the answer signal, and corresponds to the signal strength. It is characterized by determining when the distance between the portable device and the vehicle-side device is gradually increasing and when it is substantially constant.

  According to the keyless entry device according to the present invention, when the portable device is left in a range where the portable device can communicate with the vehicle-side device for a long period of time, the remaining battery level of the portable device decreases, thereby preventing the answer signal from being transmitted. However, it is possible to prevent the vehicle-side device from detecting the locking and performing the locking control, thereby preventing an unintended locking operation.

  Further, according to the keyless entry device according to the present invention, the vehicle side device does not transmit the request signal after receiving the answer signal including the information that the remaining battery level is equal to or less than the predetermined value or less than the predetermined value. Battery consumption can be prevented.

It is a schematic diagram of the keyless entry device in this embodiment. It is a block diagram of a keyless entry device. It is a flowchart in the locking operation of a door. It is a block diagram of the keyless entry device of a 2nd embodiment. It is a flowchart in the locking operation of the door in 2nd Embodiment. It is a graph showing the history pattern of signal strength.

  Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a schematic diagram of a keyless entry device according to this embodiment. The keyless entry device according to the present embodiment locks or unlocks the door 1a of the vehicle 1. The vehicle-side device 2 is provided on the vehicle 1, the user carries the portable device 3, and the vehicle-side device. Wireless communication is performed between the mobile phone 3 and the portable device 3 to perform authentication, locking / unlocking commands, and the like.

  The vehicle-side device 2 has a plurality of transmission antennas 15 at various locations of the vehicle 1, and a request signal is transmitted from each transmission antenna 15 to the portable device 3. The request signal is a low-frequency signal and is transmitted within a predetermined narrow area.

  The vehicle-side device 2 transmits the request signal intermittently, and when the door 1a is in the locked state, the user with the portable device 3 approaches the vehicle 1 and receives the request signal at the portable device 3. Then, a predetermined answer signal is transmitted to the vehicle side device 2. When the vehicle side device 2 receives the answer signal, authentication is performed, and when the authentication is established, the door 1a is unlocked. On the other hand, when the door 1a is in the unlocked state, when the user with the portable device 3 leaves the vehicle 1 and does not receive the answer signal from the portable device 3 from the state where the vehicle side device 2 receives, The vehicle side device 2 locks the door 1a. In the unlocking operation of the door 1a, a request switch or a touch sensor may be provided in the vehicle 1, and a request signal may be transmitted when this operation or contact is detected.

  FIG. 2 shows a block diagram of the keyless entry device. As shown in this figure, the vehicle-side device 2 includes a vehicle-side receiver 10 that receives an answer signal from the portable device 3, a vehicle-side transmitter 11 that transmits a request signal to the portable device 3, and a request signal. And a vehicle-side controller 12 that performs various controls when an answer signal is received.

  The vehicle-side control unit 12 has a memory 13 that stores information necessary for control such as V-ID (V-ID), which is a vehicle-specific identification code, and IDs of a plurality of portable devices that can operate one vehicle. It is connected. The vehicle-side receiving unit 10 is connected to a receiving antenna 14 for receiving an answer signal, and the vehicle-side transmitting unit 11 is connected to a plurality of transmitting antennas 15 and 15 for transmitting a request signal. The plurality of transmission antennas 15 and 15 are provided at various locations inside and outside the vehicle 1, respectively.

  The portable device 3 includes a portable device receiver 20 that receives a request signal from the vehicle-side device 2, a portable device transmitter 21 that transmits an answer signal to the vehicle-side device 2, and various types of signals when receiving a request signal. It has the portable device control part 22 which performs control, and the memory 24 which memorize | stored ID, V-ID, etc. which were set to the own machine. The portable receiver 20 is connected to a triaxial antenna 23a having directivity characteristics in directions orthogonal to each other for receiving a request signal. The portable transmitter 21 is connected to an antenna 23b for transmitting an answer signal. Is done. The portable device 3 is further driven by a battery 25, and further includes measurement means 26 that detects the remaining amount of the battery 25 and notifies the portable device control unit 22 of the detected amount.

  The portable device control unit 22 is an intermittent reception state in which the sleep state where the power consumption is substantially zero and the receivable state are switched by a wake-up signal included in the request signal from the vehicle-side device 2 received by the portable device reception unit 20. Switches to a normal state in which the receivable state continues. In addition, the portable device control unit 22 performs various operations based on commands included in the request signal. Furthermore, the portable device control unit 22 can detect the intensity of the signal received by the triaxial antenna 23.

  Next, the operation of the keyless entry device will be described. Here, when the door 1a of the vehicle 1 is in the unlocked state and the vehicle-side device 2 enters the state in which it does not receive the answer signal from the portable device 3, the flow when the door 1a is locked is performed. Will be described. In FIG. 3, the flowchart of the vehicle side apparatus 2 in the locking operation | movement of the door 1a is shown.

  The precondition of this flow is a case where the engine of the vehicle 1 is stopped and the door 1a is in an unlocked state. At this time, the vehicle side device 2 intermittently transmits a request signal. Therefore, first, the vehicle-side control unit 12 of the vehicle-side device 2 starts this flow by stopping the engine, determines whether or not it is time to transmit the request signal (step 1), and has reached the transmission timing. If so, a request signal is transmitted (step 2).

  If the portable device 3 is in an area where the request signal can be received, the portable device control unit 22 transmits an answer signal to the vehicle-side device 2. At this time, if the remaining amount of the battery 25 detected by the measuring unit 26 is less than or equal to a predetermined value or less than the predetermined value, the portable device control unit 22 sets a battery remaining amount flag (sets a flag), and the remaining amount of the battery 25 Is included in the answer signal and transmitted indicating that is less than or less than a predetermined value. If the remaining amount of the battery 25 is not less than a predetermined value or less than the predetermined value, the portable device control unit 22 does not set the remaining battery amount flag (does not set the flag), and the remaining amount of the battery 25 is not less than the predetermined value or less than the predetermined value. The indicated data is included in the answer signal and transmitted.

  After transmitting the request signal, the vehicle side control unit 12 receives the answer signal from the portable device 3 within a predetermined time and performs authentication (step 3), and when the authentication is established, the fact that the reception is established is stored as a history. Therefore, a reception flag for the answer signal is set (step 4). After setting the answer signal reception flag in step 4, the vehicle-side control unit 12 determines whether or not the answer signal includes data indicating that the remaining battery level is equal to or less than a predetermined value. (Step 5). If the data indicating that the remaining battery level is equal to or less than the predetermined value is not included, it is assumed that the battery 25 of the portable device 3 has a sufficient remaining capacity, and the normal operation is continued. That is, returning to step 1 again, the request signal is transmitted.

  On the other hand, when the answer signal is not received within the predetermined time in step 3, the vehicle-side control unit 12 determines whether or not the answer signal reception flag is set (step 6). If the answer signal is received from the portable device 3 even once while the request signal is transmitted intermittently, the answer signal reception flag is set in step 4, so in this case step 7 Proceed to This is a state in which an answer signal is received when the user with the portable device 3 moves from the communication range of the request signal to the outside of the communication range while the remaining battery level of the portable device 3 remains sufficiently Therefore, in step S7, the vehicle-side control unit 12 controls the door 1a to be locked. When the locking control of the door 1a is performed, the vehicle-side control unit 12 notifies the user of information indicating that the locking has been performed (step 8). Information notification to the user can be performed by generating sound in the vehicle 1 or generating light. When this is completed, a series of flows for locking ends, and another series of flows for unlocking starts. A series of flow for unlocking is not a main part of the present invention, and details of known techniques are omitted.

  In step 6, if no answer signal has been received from the portable device 3, the answer signal reception flag is not set. This is because it is assumed that the battery 25 of the portable device 3 has been exhausted to the extent that communication cannot be performed from the beginning, or communication is impossible for some reason. The locking operation is not performed, the information notification to the user and the automatic locking function of the door 1a are stopped in step 9, and this flow is finished. The information notification in Step 9 is different from the information notification performed in Step 9, so that the user can know that the automatic locking operation has not been performed.

  On the other hand, if the remaining battery level flag is set in the answer signal in step 5, it is assumed that the battery 25 of the portable device 3 is exhausted. In this case, the door 1a is automatically locked. The process proceeds to step 9 to stop the information notification to the user and the automatic locking function of the door 1a, and this flow is finished. Therefore, even if the battery 25 of the portable device 3 is further consumed thereafter, the locking flow itself does not start, and thus the locking control is not performed by the vehicle side device 2.

  As described above, when the measuring unit 26 detects that the remaining amount of the battery 25 of the portable device 3 is less than or less than the predetermined value, the answer signal is transmitted including the information to that effect, and the answer signal including the information is transmitted. The vehicle-side control unit 12 that has received the signal stops the automatic locking function of the door 1a and does not perform the locking control, so that the portable device 3 is left in a range where the portable device 3 can communicate with the vehicle-side device 2 for a long time. In such a case, it is possible to prevent an unintended locking operation from being performed even if the remaining battery level of the portable device 3 is reduced and an answer signal cannot be transmitted.

  Further, even if the request signal is continuously transmitted from the vehicle 1 in a state in which communication with the portable device 3 is disabled, the battery 1 of the vehicle 1 is only depleted. Thus, when the automatic locking function of the door 1a is stopped, the flow of FIG. 3 is terminated, and thereafter, the request signal is not transmitted, so that the battery of the vehicle 1 can be prevented from being consumed. If this effect is also expected, a request switch or touch sensor is provided in the vehicle 1 in the unlocking operation of the door 1a, and a request signal is transmitted when this operation or contact is detected.

  When the user replaces the battery 25 of the portable device 3, it is necessary to resume communication between the vehicle-side device 2 and the portable device 3 again. At this time, it is only necessary to start the engine and again satisfy the conditions of unlocking the door 1a and stopping the engine. When the conditions are satisfied, the flow shown in FIG. 3 is started and the locking control is enabled. The answer signal reception flag set in step 4 and the lock function stop control in step 9 are reset at the start of the flow.

  In the present embodiment, data indicating the remaining amount of the battery 25 of the portable device 3 is transmitted in the answer signal, but when the remaining amount of the battery 25 becomes less than or less than a predetermined value, this is indicated. The information shown may be included in the answer signal for transmission.

  Next, a second embodiment of the present invention will be described. Since the configuration of the keyless entry device of the second embodiment is substantially the same as that of the keyless entry device of the first embodiment, description of the common configuration is omitted. FIG. 4 shows a block diagram of the keyless entry device of the second embodiment.

  As shown in FIG. 4, the configuration of the vehicle-side device 2 is common to the first embodiment. Further, the portable device 3 does not include the measuring unit 26 that detects the remaining amount of the battery 25. On the other hand, the portable device control unit 22 has a function of detecting the strength of the request signal from the vehicle-side device 2 received by the three-axis antenna 23a, and uses the detected signal strength information as an answer signal. Can be included and sent.

  In FIG. 5, the flowchart of the vehicle side apparatus 2 in the locking operation of the door 1a in 2nd Embodiment is shown. The overall state of this flow is the same as in the first embodiment, where the door 1a of the vehicle 1 is in the unlocked state, and the flow starts when the conditions for engine stop and unlocking are satisfied. At the time. At this time, the vehicle side apparatus 2 transmits a request signal intermittently. Therefore, first, the vehicle-side control unit 12 of the vehicle-side device 2 determines whether or not it is a timing for transmitting a request signal (step 1), and transmits a request signal if the transmission timing is reached (step 2). ).

  If the portable device 3 is in an area where the request signal can be received, the portable device control unit 22 transmits an answer signal to the vehicle-side device 2. At this time, the answer signal includes information on the signal strength detected by the portable device control unit 22.

  After transmitting the request signal, the vehicle-side control unit 12 receives the answer signal within a predetermined time and performs authentication (step 3). When the authentication is established, the vehicle side control unit 12 stores that the reception is established as a history. Is set (step 4). At this time, information on the signal strength included in the answer signal is stored (step 5). This signal strength information is stored as a history so that a predetermined number can be referred back. When step 5 is executed, the flow returns to step 1 to transmit a request signal.

  On the other hand, when the answer signal is not received within the predetermined time in step 3, the vehicle-side control unit 12 determines whether or not the answer signal reception flag is set (step 6). When the answer signal reception flag is not set, the locking function is stopped and the information is notified in step 10 as in the case of NO in step 6 of the first embodiment. This is because it is assumed that the battery 25 of the portable device 3 has been exhausted to the extent that communication cannot be performed from the beginning, or communication is impossible for some reason. The locking operation is not performed, the information notification to the user and the automatic locking function of the door 1a are stopped in step 10, and this flow is finished.

  When the answer signal reception flag is set, it is recognized that the answer signal is not received from the condition where the answer signal is received. This is because the user moves away from the vehicle 1 with the portable device 3 and moves out of the communication range with the vehicle-side device 2 or the portable device 3 is left in the communication range with the vehicle-side device 2. Since it is assumed that either the battery 25 is depleted and the answer signal cannot be transmitted, or any one of the cases is assumed, the vehicle-side control unit 12 determines which one (step 7). For this purpose, the vehicle-side control unit 12 refers to a history of signal strength information included in the answer signal.

  The signal strength information detected by the portable device 3 corresponds to the distance between the portable device 3 and the vehicle-side device 2, more specifically, the distance between the portable device 3 and the transmission antenna 15. As the distance between the portable device 3 and the transmission antenna 15 increases, the signal strength detected by the portable device 3 decreases. In the present embodiment, a plurality of transmission antennas 15 are provided, but here, the signal intensity from any one of the transmission antennas 15, for example, the transmission antennas 15 provided in the door 1 a of the driver's seat may be used.

  FIG. 6 shows a graph showing a signal intensity history pattern. In any graph, the horizontal axis represents time, and the vertical axis represents the distance between the portable device 3 and the vehicle-side device 2 corresponding to the signal intensity. Here, the history pattern for the latest five times from the time when the answer signal is not received is shown.

  In FIG. 6A, the distance between the portable device 3 and the vehicle-side device 2 gradually increases with the passage of time, and finally the answer signal cannot be received. From this history, when the user moves away from the vehicle 1 with the portable device 3, the distance between the portable device 3 and the vehicle-side device 2 gradually increases, and finally the portable device 3 is out of the communication range. It is speculated that it came out.

  On the other hand, in FIG. 6B, the distance between the portable device 3 and the vehicle-side device 2 is substantially constant even when time elapses, and finally the answer signal cannot be received. From this history, it is presumed that the portable device 3 is left in the communication range with the vehicle-side device 2 and the battery 25 is depleted and the answer signal cannot be transmitted.

  Therefore, the vehicle-side control unit 12 refers to the latest history at the time when the answer signal is not received, and calculates the slope of the distance between the portable device 3 and the vehicle-side device 2 corresponding to the signal strength with respect to time. If the inclination is larger than a predetermined value, it is determined that the user has left the vehicle 1 with the portable device 3, and the vehicle-side control unit 12 performs locking control of the door 1a (step 8). Moreover, if the locking control of the door 1a is performed, the vehicle side control part 12 will perform the information notification which shows having locked the user (step 9).

  In step 7, if the slope of the distance between the portable device 3 corresponding to the signal strength and the vehicle side device 2 is smaller than a predetermined value and substantially constant, the portable device 3 is not moved and the battery 25 is consumed as it is. The vehicle-side control unit 12 does not automatically lock the door 1a, stops the information notification to the user and the automatic locking function of the door 1a in step 10, and executes this flow. finish.

  In the second embodiment, whether or not the portable device 3 is moving is determined based on whether or not the slope of the distance between the portable device 3 and the vehicle-side device 2 with respect to time is larger than a predetermined value. It is sufficient that the tendency of gradually moving from 3 can be confirmed, or it may be confirmed that it is other than the stop.

  In this flow, the signal intensity information of the request signal transmitted from the vehicle-side controller 12 detected in the portable device 3 is converted into a distance, and the portable device 3 moves the magnitude of the slope of the distance with respect to the time axis. However, the signal strength information may be used as it is. In this case, when the portable device 3 moves out of the communication range, the signal strength of the request signal received by the portable device 3 gradually decreases with respect to time. Whether the slope is a negative value is a determination condition.

  In this way, the strength of the signal received by the portable device 3 is detected and transmitted by including this strength information in the answer signal, and the vehicle-side control unit 12 stores the history of the strength information and receives the answer signal. When it becomes a state where it does not receive from the state, the history of information according to the signal strength included in the received answer signal is referred to, and the distance between the portable device 3 and the vehicle side device 2 corresponding to the signal strength is gradually increased. If the distance between the portable device 3 corresponding to the signal strength and the vehicle-side device 2 is substantially constant, the portable device 3 may be connected to the vehicle side. To prevent an unintentional locking operation from being performed even if the remaining battery level of the portable device 3 decreases and the answer signal cannot be transmitted when left in a range where it can communicate with the device 2 for a long time. Can do.

  Also in this case, when the automatic locking function of the door 1a is stopped, the flow of FIG. 5 is terminated, and thereafter, the request signal is not transmitted, thereby preventing the battery of the vehicle 1 from being consumed. Although it is possible, this is the same as in the first embodiment.

  In the second embodiment, the movement of the portable device 3 is determined from the intensity of the request signal received by the portable device 3 and can be clearly distinguished because it can be clearly distinguished, but the vehicle-side control unit 12 It may be judged from the strength of the answer signal received in step (b). Specifically, the transmission strength of the portable device 3 decreases with a decrease in the remaining battery level of the portable device 3, and the reception strength received by the vehicle-side device 2 decreases accordingly. Further, the reception intensity received by the vehicle-side device 2 also decreases when the user leaves the portable device 3. By the way, since the battery remaining capacity does not decrease rapidly, the reception strength gradually decreases in this case. On the other hand, since the decrease in the reception intensity accompanying the movement is rapid, it can be determined whether or not the portable device 3 is moving from the degree of the decrease. In the second embodiment, it is determined whether or not the mobile device 3 is moving due to a change in strength. However, the absolute position of the portable device 3 is identified each time based on the reception strength of at least three transmission antennas 15 and moved. You may make it judge whether it is doing.

  Although the embodiment of the present invention has been described above, the application of the present invention is not limited to this embodiment, and can be applied in various ways within the scope of its technical idea.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Vehicle side apparatus 3 Portable machine 10 Vehicle side receiving part 11 Vehicle side transmission part 12 Vehicle side control part 13 Memory 14 Reception antenna 15 Transmission antenna 20 Portable machine receiving part 21 Portable machine transmission part 22 Portable machine control part 23a Triaxial Antenna 25 Battery 26 Measuring means

Claims (5)

In a keyless entry device having a vehicle-side device that is provided in a vehicle and intermittently transmits a request signal and receives an answer signal, and a portable device that receives the request signal and transmits an answer signal,
The vehicle-side device includes a vehicle-side control unit that performs predetermined control when an answer signal from the portable device is authenticated, and the vehicle-side control unit receives a response signal from the portable device and does not receive the answer signal. When it becomes, perform the locking control to lock the door of the vehicle,
The portable device receives a request signal transmitted from the vehicle side device and returns an answer signal when authentication is established, a battery for driving, and a measuring means for detecting the remaining amount of the battery Prepared,
When the portable device control unit detects that the remaining amount of the battery is equal to or less than a predetermined value or less than a predetermined value by the measurement unit, the portable device control unit transmits an answer signal including information to that effect,
The vehicle-side control unit stops the locking control when receiving an answer signal including information indicating that the remaining amount of the battery is below a predetermined level or below a predetermined level.   2. The keyless entry device according to claim 1, wherein the vehicle-side control unit does not transmit a request signal after receiving an answer signal including information indicating that the remaining amount of the battery is equal to or less than a predetermined value or less than a predetermined value. . In a keyless entry device having a vehicle-side device that is provided in a vehicle and intermittently transmits a request signal and receives an answer signal, and a portable device that receives the request signal and transmits an answer signal,
The vehicle-side device includes a vehicle-side control unit that performs predetermined control when an answer signal from the portable device is authenticated, and the vehicle-side control unit receives a response signal from the portable device and does not receive the answer signal. When it becomes, perform the locking control to lock the door of the vehicle,
The portable device includes a portable device control unit that transmits an answer signal when receiving a request signal transmitted from the vehicle-side device, and a battery for driving.
The portable device control unit transmits an answer signal including information according to the signal strength from the vehicle side device,
When the vehicle-side control unit is in a state of not receiving an answer signal from the portable device, the vehicle-side control unit records a signal history included in the received answer signal or a history of information corresponding to the signal strength of the answer signal. If the distance between the portable device corresponding to the signal strength and the vehicle side device is gradually increased, the locking control is performed, and the distance between the portable device corresponding to the signal strength and the vehicle side device is substantially constant. In some cases, the keyless entry device does not perform the locking control.   The vehicle-side control unit is in a state in which the answer signal from the portable device is received and is not received, and the signal strength is substantially reduced by a history of information corresponding to the signal strength included in the received answer signal. 4. The keyless entry device according to claim 3, wherein when it is constant, no request signal is transmitted thereafter.   The vehicle-side control unit refers to a signal history included in the received answer signal or a history of information corresponding to the signal strength of the answer signal, and the distance between the portable device corresponding to the signal strength and the vehicle-side device is gradually increased. 4. The keyless entry device according to claim 3, wherein a determination is made as to whether the distance is long or substantially constant.

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