JP5815472B2 - Integrated receiver - Google Patents

Description

  The present invention relates to an integrated receiver capable of receiving both radio waves from an electronic key system and tire pressure monitoring systems.

  2. Description of the Related Art Conventionally, many vehicles are equipped with an electronic key system that performs key verification by electronic communication with an electronic key. As an electronic key system, for example, a key operation free system that performs ID collation (smart collation) by narrow-band radio triggered by communication from a vehicle is well known. Further, in recent vehicles, a tire pressure sensor is attached to each tire, a tire pressure signal transmitted from the tire pressure sensor is transmitted wirelessly to the vehicle body, and a tire pressure monitoring system (TPMS: There is also a tendency to install Tire Pressure Monitoring System.

  By the way, in the case of the current system, the radio wave transmitted from the electronic key and the radio wave transmitted from the tire pressure sensor are both radio waves in the UHF (Ultra High Frequency) band. Therefore, using a receiver mounted on the vehicle body as a common receiver (integrated receiver) for the electronic key system and the tire pressure monitoring system is being studied with the aim of reducing the number of parts of the vehicle (for example, patents). Reference 1 etc.).

Japanese Patent No. 4552959

  By the way, in this type of tire pressure monitoring system, although not limited to the integrated receiver, it is general to perform the tire pressure monitoring operation while the vehicle is powered on or running. However, immediately after the start of travel, it is not always possible to acquire air pressure from all four tires, for example, due to noise or tire rotation position, it may not be possible to acquire air pressure from a particular tire, There was a problem that it took time until the air pressure of all tires could be acquired. Therefore, if the driver can be notified of a tire low pressure alarm immediately after the start of driving, safe driving can be ensured, and there is a need for technological development that can satisfy this.

  An object of the present invention is to provide an integrated receiver capable of monitoring tire pressure even when the vehicle power is off.

In order to solve the above problems, in the present invention, an electronic key system that verifies the validity of an electronic key by wireless communication, and a tire pressure signal is wirelessly transmitted to a vehicle body from a sensor unit attached to the tire, thereby obtaining the tire pressure. In an integrated receiver shared by the tire pressure monitoring system for monitoring in the vehicle body, vehicle power supply state monitoring means for monitoring the power supply state of the vehicle, and the electronic implemented in this situation when the vehicle power supply is turned off Tire pressure monitoring execution means for executing tire pressure monitoring operation in synchronization with the communication operation of the key system, and when the vehicle power is turned on, the operation state from the authentication control unit that controls the operation of the electronic key system on the vehicle body side When the switching signal is input, the operation mode becomes the electronic key system mode, and when the operation state switching signal is not input, the operation mode is changed. Becomes Ya pressure monitoring system for a mode, the tire pressure monitoring execution means, when the vehicle power is off, by confirming the input whether the operation state switching signal, to decide whether or not to execute the operation of the tire pressure monitoring Is the gist.

According to the configuration of the present invention, when the vehicle power source is turned off, the tire pressure monitoring system is operated in synchronization with the operation of the electronic key system performed at this time. It becomes possible to monitor. When a low-pressure tire is detected when the vehicle power is off, it is stored in the memory, and a tire low pressure alarm is notified to the user when the vehicle power is switched on. For this reason, when the vehicle power is switched on, a tire low pressure alarm can be immediately notified to the user. According to this configuration, it is determined whether or not to execute the operation of the tire pressure monitor when the vehicle power is off, using the operation state switching signal used for setting the mode of the integrated receiver when the vehicle power is on. . Therefore, since it is possible to set an operation using a signal that originally exists, it is not necessary to provide a new signal for setting an operation.

  The gist of the present invention is that the synchronization is a process of performing the tire pressure monitoring operation immediately after one communication operation of the electronic key system that is repeatedly performed when the vehicle power is turned off. According to this configuration, since the tire pressure monitoring operation when the vehicle power is off is performed after the communication operation of the electronic key system, the operation of the electronic key system and the tire pressure monitoring operation do not overlap. For this reason, it is possible to perform the tire pressure monitoring operation when the vehicle power is off without being affected by the electric wave of the electronic key.

  The gist of the present invention is that the synchronization is a process of simultaneously performing one communication operation of the electronic key system and the tire pressure monitoring operation that are repeatedly performed when the vehicle power is turned off. According to this configuration, the communication operation of the electronic key system and the tire air pressure monitoring operation when the vehicle power is turned off are executed at the same time, so that the processing efficiency can be improved.

  In the present invention, a receiving circuit for demodulating received radio waves and a tire pressure monitoring microcomputer for controlling the operation of tire pressure monitoring are provided. Power is supplied to the tire pressure monitoring microcomputer, the battery power is supplied to the authentication control unit from between the battery and the fuse, and the operation state switching signal output from the authentication control unit is the tire pressure. Although also supplied as a power source for the monitoring microcomputer, when the fuse is removed, the battery power is not supplied to the tire pressure monitoring microcomputer, and the tire pressure monitoring system mode does not work. The receiving circuit having an operation state switching signal as a power source By supplying to the gist that works as a mode for the electronic key system. According to this configuration, when the vehicle power is off, if the fuse is removed during periods when tire pressure monitoring is not required, the battery power will not be consumed by the tire pressure monitoring microcomputer, thus saving battery power. It becomes possible to do. Therefore, even if the tire pressure monitoring operation can be performed when the vehicle power is off, it is possible to take measures to save battery power. Further, when the fuse is removed, an operation switching signal is supplied to the receiving circuit as a power source, so that the integrated receiver can be operated as a receiver of the electronic key system. Therefore, there is no inconvenience that the electronic key system cannot be used when removing the fuse.

  The gist of the present invention is that the communication operation is a polling operation for periodically confirming establishment of communication with the electronic key while the vehicle is parked or stopped. According to this configuration, since the tire pressure monitoring operation when the vehicle power is off can be performed in conjunction with the polling operation, the tire pressure monitoring operation when the vehicle power is off is performed at a suitable timing called the polling interval. It becomes possible to carry out.

  According to the present invention, the tire pressure can be monitored even when the vehicle power is off.

The block diagram of the electronic key system and tire pressure monitoring system of one Embodiment. The timing chart which shows the communication outline | summary when controlling an integrated receiver only by a smart reception request signal at the time of normal. The timing chart which shows the communication outline | summary when controlling an integrated receiver by a smart reception request signal and a smart frequency switching signal at the time of normal. The timing chart explaining the operation | movement which an integrated receiver takes during vehicle power-on. The timing chart explaining the operation | movement which an integrated receiver takes during vehicle power-off. The timing chart explaining the operation | movement which an integrated receiver takes in the vehicle power-off of another example.

Hereinafter, an embodiment of an integrated receiver embodying the present invention will be described with reference to FIGS.
As shown in FIG. 1, the vehicle 1 is provided with an electronic key system 3 that performs key verification (ID verification) wirelessly with the electronic key 2. The electronic key system 3 of this example performs ID collation (smart collation) by narrow-band radio (communication distance: several m) triggered by communication from the vehicle 1, and permits operation of in-vehicle devices on the condition that this collation is established / It is a key operation free system to be executed. In addition, a tire pressure sensor (also referred to as a tire valve) 5 is attached to each tire 4 in the vehicle 1, and a tire pressure signal Stp detected by the tire pressure sensor 5 is wirelessly transmitted to the vehicle body 6. A tire pressure monitoring system 7 for monitoring is provided. The tire pressure sensor 5 corresponds to a sensor unit.

  The vehicle body 6 is provided with a verification ECU (Electronic Control Unit) 8 that authenticates the validity of the electronic key 2 in the electronic key system 3, a body ECU 9 that manages the power supply of the in-vehicle electrical components, and an engine ECU 10 that controls the engine. These are connected via the in-vehicle bus 11. An electronic key ID is written and stored in each memory (not shown) of the electronic key 2 and the verification ECU 8. Connected to the verification ECU 8 are an in-vehicle transmitter 12 capable of transmitting LF (Low Frequency) band radio waves outside the vehicle and an in-vehicle transmitter 13 capable of transmitting LF band radio waves inside the vehicle. The verification ECU 8 corresponds to an authentication control unit.

  The tire pressure sensor 5 includes a controller 14 that controls the operation of the tire pressure sensor 5, a pressure sensor 15 that detects the pressure of the tire 4, an acceleration sensor 16 that detects acceleration in the rotational direction applied to the tire 4, and a UHF band sensor. A transmission unit 17 capable of transmitting radio waves is provided. A tire ID (valve ID) unique to each sensor is registered in a memory (not shown) of the controller 14. The controller 14 measures the tire pressure based on the detection signal of the pressure sensor 15 and periodically transmits the tire pressure signal Stp. The controller 14 also transmits a tire air pressure signal Stp to the vehicle body 6 when it is confirmed by the detection signal of the acceleration sensor 16 that the tire 4 has started rotating, that is, the vehicle 1 has entered the running state. The tire pressure signal Stp includes a tire ID, tire pressure data, and the like.

  The vehicle body 6 is provided with an integrated receiver 18 that can receive radio waves in the UHF band as a common receiver for the electronic key system 3 and the tire pressure monitoring system 7. The integrated receiver 18 is electrically connected to the verification ECU 8 and the body ECU 9. The integrated receiver 18 can receive both the UHF radio wave transmitted from the electronic key 2 and the UHF radio wave transmitted from the tire pressure sensor 5.

  The integrated receiver 18 is provided with a TPMS microcomputer 19 that executes the receiving operation of the tire pressure monitoring system 7 in the integrated receiver 18 and a receiving IC (Integrated Circuit) 20 that demodulates and amplifies the received radio wave. . The four tire IDs are written and stored in the memory 21 of the TPMS microcomputer 19. A plurality (two in this example) of reception antennas 23 are connected to the antenna connection terminal 22 of the reception IC (reception circuit) 20 via a switch unit 24. The receiving antenna 23 includes, for example, an in-vehicle antenna installed in the vehicle, a luggage antenna installed in the luggage, and the like. The switch unit 24 selectively connects one of the two reception antennas 23 to the reception IC 20. The TPMS microcomputer 19 corresponds to a tire pressure monitoring microcomputer.

  The integrated receiver 18 is provided with a series circuit of a regulator 25 for power supply adjustment and a diode 26. In this series circuit, the input side is connected to the power input terminal 27 of the integrated receiver 18, and the output side is connected to the power terminal 28 of the TPMS microcomputer 19 and the power terminal 30 of the receiving IC 20 via the diode 29. The power input terminal 27 is connected to the battery 32 via a detachable fuse 31. The regulator 25 supplies a power supply voltage Vc (for example, 5 V) to the TPMS microcomputer 19 and the receiving IC 20.

  The integrated receiver 18 is provided with an IG signal input terminal 34 for inputting a vehicle power-on signal (IG signal) Sig from the ignition switch 33. The IG signal input terminal 34 is connected to the IG terminal 35 of the TPMS microcomputer 19 in the integrated receiver 18, and the power input terminal 27 and the midpoint 36 of the fuse 31 via the ignition switch 33 outside the integrated receiver 18. It is connected to the. The vehicle power on refers to a state when the ignition switch 33 is operated to, for example, an ACC (Accessory) on position, an IG (Ignition) on position, an engine start position, or the like.

  The data output terminal 37 of the reception IC 20 is connected to the verification ECU 8 via the data output terminal 38 of the integrated receiver 18 and is also connected to the data input terminal 39 of the TPMS microcomputer 19. The receiving IC 20 can output the received data from the data output terminal 37 to the verification ECU 8 and the TPMS microcomputer 19. The TPMS microcomputer 19 is connected to the body ECU 9 via the control terminal 40 of the integrated receiver 18.

  The integrated receiver 18 is provided with a smart reception request signal input terminal 41 for inputting a smart reception request signal Srco output from the verification ECU 8. The smart reception request signal input terminal 41 is connected to the operation switching terminal 42 of the TPMS microcomputer 19 and the first switching terminal 43 of the reception IC 20. The smart reception request signal Srco is a request for switching the operation mode of the integrated receiver 18 to the “smart communication mode” for operating as a receiver of the electronic key system 3, and includes a pulse signal having a predetermined pulse. The smart reception request signal Srco corresponds to an operation state switching signal.

  The integrated receiver 18 is provided with a smart frequency switching signal input terminal 44 for inputting the smart frequency switching signal Scsel output from the verification ECU 8. The smart frequency switching signal input terminal 44 is connected to the second switching terminal 45 of the receiving IC 20. The smart frequency switching signal Scsel is a request for switching the reception frequency in the “smart communication mode”, and includes a pulse signal having a predetermined pulse.

  The integrated receiver 18 is provided with an antenna switching signal input terminal 46 for inputting the antenna switching signal Sasel from the verification ECU 8. The antenna switching signal input terminal 46 is connected to the switch unit 24 through electrical wiring. The antenna switching signal Sasel is a request for switching the reception antenna 23 to be used, and is composed of a pulse signal having a predetermined pulse. The switch unit 24 selects the reception antenna 23 to be used based on the antenna switching signal Sasel.

  The receiving IC 20 is provided with a mode setting unit 47 that sets the operation mode of the integrated receiver 18 based on the smart reception request signal Srco and the smart frequency switching signal Scsel. When the smart reception request signal Srco pulse is input from the verification ECU 8, the mode setting unit 47 switches the operation mode of the reception IC 20 to “smart communication mode”. The “smart communication mode” is a mode in which a reception frequency (for example, 312/314 MHz) of a radio wave transmitted from the electronic key 2 is taken and the radio wave can be read. Further, if the pulse of the smart reception request signal Srco is not input from the verification ECU 8, the mode setting unit 47 switches the operation mode of the reception IC 20 to “TPMS communication mode”. The “TPMS communication mode” is a mode that takes a reception frequency (for example, 315 MHz) of a radio wave transmitted from the tire pressure sensor 5 and can read this radio wave.

  In addition, when the mode setting unit 47 is in the “smart communication mode” and the pulse of the smart frequency switching signal Scsel is not input from the verification ECU 8, the “first smart communication mode” in which the reception frequency is the first frequency (314 MHz). To. On the other hand, in the “smart communication mode”, the mode setting unit 47 sets the “second smart communication mode” in which the reception frequency is the second frequency (312 MHz) when the pulse of the smart frequency switching signal Scsel is input from the verification ECU 8.

  The TPMS microcomputer 19 inputs a smart reception request signal Srco from the verification ECU 8. When the smart reception request signal Srco is not input, the TPMS microcomputer 19 determines that the operation mode of the integrated receiver 18 is “TPMS communication mode”. In this state, the TPMS microcomputer 19 executes the tire pressure monitoring operation on condition that the vehicle power-on signal Sig is input from the ignition switch 33.

  The TPMS microcomputer 19 causes the vehicle power supply state monitoring unit 48 that monitors the switch state of the ignition switch 33 and the tire pressure monitoring operation in synchronization with the smart communication operation that is performed at this time when the vehicle power is off. A communication synchronization processing unit 49 is provided. The vehicle power supply state monitoring unit 48 monitors a switch signal input from the ignition switch 33. The communication synchronization processing unit 49 stops the tire air pressure monitoring operation at the end timing of the smart communication that is periodically executed (in the polling cycle) when the vehicle power is turned off, so that the pulse of the smart reception request signal Srco is not input. Let it run. The vehicle power supply state monitoring unit 48 corresponds to vehicle power supply state monitoring means, and the communication synchronization processing unit 49 corresponds to tire pressure monitoring execution means.

  The smart reception request signal Srco is input to the power supply terminal 30 of the reception IC 20 via the diode 50. Thereby, the smart reception request signal Srco of this example is also used as a power supply (5 V) of the reception IC 20. Therefore, the power supply of the reception IC 20 includes the regulator 25 and the OR circuit of the smart reception request signal Srco. Therefore, even if the fuse 31 is removed and the power supply from the regulator 25 is stopped, the reception IC 20 can operate using the smart reception request signal Srco as a power source by inputting the smart reception request signal Srco.

Next, the operation of the integrated receiver 18 of this example will be described with reference to FIGS.
[Mode switching operation: When controlling only the smart reception request signal]
As shown in FIG. 2, when the ignition switch 33 is turned on, for example, when the engine of the vehicle 1 is operating, the verification ECU 8 sends both the smart reception request signal Srco and the smart frequency switching signal Scsel to the integrated receiver 18. Do not output. At this time, since the receiving IC 20 does not input a pulse at either the first switching terminal 43 or the second switching terminal 45, the operation mode of the receiving IC 20 is set to “TPMS communication mode” by the mode setting unit 47. Further, since the TPMS microcomputer 19 does not input the pulse of the smart reception request signal Srco, the tire pressure monitoring operation is executed. Therefore, the integrated receiver 18 can receive the tire pressure signal Stp transmitted from the tire pressure sensor 5.

  The collation ECU 8 outputs a smart reception request signal Srco to the integrated receiver 18 when the smart collation execution timing comes. The integrated receiver 18 inputs this smart reception request signal Srco at the smart reception request signal input terminal 41. At this time, since the mode setting unit 47 inputs the pulse of the smart reception request signal Srco at the first switching terminal 43, the operation mode of the reception IC 20 is switched to the “smart communication mode”. Further, since the TPMS microcomputer 19 inputs the pulse of the smart reception request signal Srco, the tire pressure monitoring operation is stopped. Here, since the smart frequency switching signal Scsel is not output from the verification ECU 8, the operation mode is set to “first smart communication mode”.

  In the “first smart communication mode”, when the electronic key 2 is outside the vehicle, as shown in FIG. 1, the vehicle-external transmitter 12 LF-transmits the request signal Srq for ID reply outside the vehicle at the first frequency, The ID signal Sid of the electronic key 2 that has received the request signal Srq is returned. When the integrated receiver 18 receives this ID signal Sid, it outputs it to the verification ECU 8. The verification ECU 8 performs ID verification (external smart verification) based on the ID signal Sid input from the integrated receiver 18, and permits / executes door lock locking / unlocking if this verification is established. If the electronic key 2 is in the vehicle, the request signal Srq is transmitted from the in-vehicle transmitter 13 and ID verification (in-vehicle smart verification) is performed in the same manner as outside the vehicle. If this verification is established, engine start by the engine switch 52 is permitted.

  When the verification ECU 8 confirms that the smart verification does not have to be performed, the verification ECU 8 does not output the smart reception request signal Srco to the integrated receiver 18. That is, the reception IC 20 does not input the smart reception request signal Srco from the verification ECU 8. Therefore, when the smart reception request signal Srco is no longer input at the first switching terminal 43, the mode setting unit 47 switches the operation mode of the reception IC 20 from “first smart communication mode” to “TPMS communication mode”. Further, since the TPMS microcomputer 19 stops inputting the pulse of the smart reception request signal Srco when the vehicle power is turned on, the operation of tire pressure monitoring is started. Thus, the integrated receiver 18 can operate in the “TPMS communication mode” and can receive the tire pressure signal Stp transmitted from the tire pressure sensor 5.

[Mode switching operation: Control of smart reception request signal and smart frequency switching signal]
As shown in FIG. 3, when the smart reception request signal Srco is input at the first switching terminal 43 in the “TPMS mode”, the mode setting unit 47 switches the operation mode of the reception IC 20 to the “first smart communication mode”. . At this time, the integrated receiver 18 performs the reception operation in the “first smart communication mode”, but when the verification ECU 8 confirms that the smart communication is not established at the first frequency, the integrated receiver 18 transmits the smart frequency switching signal Scsel. Output to. The smart communication establishment determination is performed by, for example, not receiving radio waves for a certain period of time or detecting noise.

  When the smart reception request signal Srco is input at the first switching terminal 43 and the smart frequency switching signal Scsel is input at the second switching terminal 45, the mode setting unit 47 sets the operation mode of the receiving IC 20 to “second smart communication mode”. Switch. As a result, the integrated receiver 18 executes smart communication with the reception frequency set to the second frequency.

  Thereafter, the verification ECU 8 executes smart verification while periodically switching the “smart communication mode” of the integrated receiver 18 to the “first smart communication mode” or the “second smart communication mode”. This is because when the electronic key 2 receives the smart verification radio wave from the vehicle 1, the electronic key 2 first transmits the radio wave at the first frequency. If there is no response from the vehicle 1, the electronic key 2 switches to the second frequency and transmits the radio wave. This is because the operation to retry transmission is taken. In this way, the vehicle 1 and the electronic key 2 perform smart verification.

  When the verification ECU 8 confirms that the smart verification need not be performed, the verification ECU 8 does not output the smart reception request signal Srco and the smart frequency switching signal Scsel. That is, the receiving IC 20 does not input the smart reception request signal Srco and the smart frequency switching signal Scsel from the verification ECU 8. When the smart reception request signal Srco is no longer input at the first switching terminal 43, the mode setting unit 47 switches the operation mode of the reception IC 20 from “second smart communication mode” to “TPMS communication mode”. Further, since the TPMS microcomputer 19 stops inputting the pulse of the smart reception request signal Srco when the vehicle power is turned on, the operation of tire pressure monitoring is started. Thereby, the integrated receiver 18 operates as a receiver of the tire pressure monitoring system 7.

[Operation while vehicle power is on]
As shown in FIG. 4, the operation that the vehicle 1 should take while the vehicle power is on is monitoring the tire air pressure, and the smart verification with the electronic key 2 is not necessarily performed. Therefore, the verification ECU 8 does not output the smart reception request signal Srco to the integrated receiver 18 while the vehicle power is on. For this reason, since the receiving IC 20 does not input the smart reception request signal Srco at the first switching terminal 43, the operation mode is set to “TPMS communication mode” by the mode setting unit 47.

  In addition, when the vehicle power is turned on, the TPMS microcomputer 19 inputs a pulse of the vehicle power on signal Sig from the ignition switch 33. Therefore, the TPMS microcomputer 19 does not input the smart reception request signal Srco from the verification ECU 8 when the vehicle power is turned on, so the tire pressure monitoring operation is executed. Thereby, the integrated receiver 18 operates as a receiver of the tire pressure monitoring system 7 while the vehicle power is on.

  Here, it is assumed that the vehicle 1 starts traveling. At this time, as shown in FIG. 1, the controller 14 of the tire pressure sensor 5 detects the rotation of the tire 4 based on the detection signal from the acceleration sensor 16 and transmits the tire pressure signal Stp from the transmission unit 17. Incidentally, each tire pressure sensor 5 of the four wheels transmits a tire pressure signal Stp with a predetermined time difference so that radio waves do not interfere with each other.

  Since the integrated receiver 18 is in the “TPMS communication mode” at this time, the integrated receiver 18 can receive the tire pressure signal Stp transmitted from the tire pressure sensor 5. The receiving IC 20 outputs the tire pressure signal Stp received by the receiving antenna 23 to the TPMS microcomputer 19. The TPMS microcomputer 19 authenticates the validity of the tire ID in the tire pressure signal Stp, and confirms the tire pressure data included in the same tire pressure signal Stp if this tire ID verification is established. The TPMS microcomputer 19 outputs a tire abnormality notification request to the body ECU 9 when detecting that the tire air pressure is a low pressure equal to or lower than a specified value. When the body ECU 9 inputs a tire abnormality notification request from the TPMS microcomputer 19, the body ECU 9 notifies a tire low pressure alarm, for example, on an instrument panel in the vehicle.

[Operation while vehicle power is off]
As shown in FIG. 5, when the vehicle power is off, for example, the vehicle 1 is parked and stopped. For example, the vehicle door is locked and unlocked and the engine is started. Need to be run regularly. At this time, the verification ECU 8 periodically transmits a request signal Srq (specifically, a wake signal) at a predetermined polling period to check whether smart communication with the electronic key 2 is established. Therefore, the verification ECU 8 periodically outputs the smart reception request signal Srco to the integrated receiver 18 at the execution timing of smart communication.

  When the smart reception request signal Srco is input from the verification ECU 8, the mode setting unit 47 switches the operation mode of the reception IC 20 to “smart communication mode”. Further, since the TPMS microcomputer 19 inputs the pulse of the smart reception request signal Srco, the tire pressure monitoring operation is stopped. As a result, the integrated receiver 18 performs a reception operation in the “smart communication mode” while the pulse of the smart reception request signal Srco is output.

  When one polling operation ends, the verification ECU 8 does not output the smart reception request signal Srco at that timing. When the communication synchronization processing unit 49 detects the non-input (pulse falling) of the smart reception request signal Srco in the situation where the vehicle power supply OFF is recognized based on the monitoring result of the vehicle power supply state monitoring unit 48, the communication synchronization processing unit 49 To start the tire pressure monitoring operation. That is, the tire pressure monitoring operation is also executed continuously immediately after each smart communication executed at a predetermined polling period while the vehicle power is off. This makes it possible to monitor the tire pressure not only when the vehicle power is on but also when the vehicle power is off.

  When monitoring the tire pressure while the vehicle power is off, the TPMS microcomputer 19 receives the tire pressure signal Stp and checks the tire pressure by the same process as when the vehicle power is on. At this time, when the TPMS microcomputer 19 detects a low-pressure tire from the received tire pressure signal Stp, the TPMS microcomputer 19 temporarily holds a tire abnormality notification request in the memory 21. The TPMS microcomputer 19 outputs a tire abnormality notification request held in the memory 21 to the body ECU 9 at the time of activation corresponding to the vehicle power on, and causes the body ECU 9 to execute the tire abnormality notification. Thereby, tire abnormality notification is implemented immediately after switching from vehicle power-off to vehicle power-on.

[Operation when fuse is removed]
If the tire air pressure monitoring is enabled even when the vehicle power is off, for example, when the vehicle 1 is transported over a long distance, the integrated receiver 18 will operate periodically even though it is not necessary. It will lead to. Therefore, when the tire pressure monitoring system 7 is unnecessary, it is preferable to remove the fuse 31 so that the power of the battery 32 is not consumed by the integrated receiver 18. However, if the power supply to the integrated receiver 18 is completely cut off, the electronic key system 3 is also invalidated, which is inconvenient when operating the door lock and unlocking or starting the engine. .

  Therefore, in the case of this example, the power supply path of the verification ECU 8 and the integrated receiver 18 can be taken from the front and back of the fuse 31, the verification ECU 8 is connected to the side closer to the battery 32 than the fuse 31, and the integrated reception is performed on the opposite side. Connect the machine 18. Then, the smart reception request signal Srco output from the verification ECU 8 is input to the reception IC 20 and can be used as a power source for the reception IC 20. Therefore, even if the fuse 31 is removed in order to save the power of the battery 32, the integrated receiver 18 can perform the smart communication reception operation. Can be said to be good.

According to the configuration of the present embodiment, the following effects can be obtained.
(1) When the vehicle power is off, the tire air pressure monitoring operation can be executed even when the vehicle power is off by synchronizing the tire air pressure monitoring operation with the smart communication that is intermittently performed at this time. When the tire pressure is monitored while the vehicle power is off, when a low pressure tire is detected, it is held in the memory 21 and a tire low pressure alarm is issued when the vehicle power source is switched on. . Therefore, the tire pressure can be monitored not only when the vehicle power is on but also when the vehicle power is off.

  (2) Since the tire pressure is monitored while the vehicle power is off and the vehicle power is turned on, that is, when the vehicle power is turned on, the monitoring result is notified. An alarm can also be given.

  (3) The tire pressure monitoring operation performed when the vehicle power is off is synchronized with the smart communication executed when the vehicle power is off. For this reason, the integrated receiver 18 whose power is turned on for smart communication can be shifted to the tire pressure monitoring operation as it is, so that it is possible to suppress power consumption required for power-up. In addition, since the number of power-on operations can be reduced, it also contributes to a reduction in processing time for smart communication and tire pressure monitoring operation when the vehicle power is off. Furthermore, since the smart communication and tire pressure monitoring operation when the vehicle power is turned off are a set of operations, even if the tire pressure monitoring operation is added when the vehicle power is turned off, it will affect the original smart communication. Nor.

  (4) The tire pressure monitoring operation that is performed when the vehicle power is turned off is performed immediately after the smart communication that is also performed when the vehicle power is turned off. Therefore, smart communication and tire pressure monitoring operation do not overlap. Therefore, the tire pressure monitoring operation when the vehicle power is off can be performed without being affected by the radio wave of smart communication.

  (5) The smart reception request signal Srco output from the verification ECU 8 is input to the TPMS microcomputer 19, and the presence or absence of pulse input of the smart reception request signal Srco is used as a determination material to monitor tire pressure when the vehicle power is off. Decide whether to perform the action. Therefore, it is possible to set the operation of the TPMS microcomputer 19 using a signal existing from the beginning, so that it is not necessary to provide a new signal for setting the operation.

  (6) If the fuse 31 is removed during a period when the tire pressure monitoring operation is unnecessary, such as when the vehicle is powered off, for example, when transporting over a long distance, the integrated receiver 18 does not execute the tire pressure monitoring operation. Thus, the battery 32 can be saved in power. Therefore, even if it is possible to perform the tire pressure monitoring operation when the vehicle power is off, it is possible to take measures to save the battery 32 power. Further, when the fuse 31 is removed, the smart reception request signal Srco is supplied to the reception IC 20 as a power source, so that the integrated receiver 18 can be maintained to operate as a receiver for smart communication. Therefore, there is no inconvenience that the electronic key system 3 cannot be used when the fuse 31 is removed.

  (7) Since the tire pressure monitoring operation when the vehicle power is off is performed in conjunction with the polling operation of the smart communication, the tire pressure monitoring operation when the vehicle power is off can be performed at a suitable timing called a polling interval. it can.

Note that the embodiment is not limited to the configuration described so far, and may be modified as follows.
As shown in FIG. 6, when the vehicle power is off, smart communication and tire pressure monitoring operation may be executed simultaneously. This requires that the frequency of each radio wave for smart communication and tire pressure monitoring operation is the same (substantially the same) and the data rate is close. By doing so, it is possible to simultaneously receive the radio wave for smart communication and the radio wave for tire pressure monitoring communication, which contributes to efficient processing.

  -When smart communication at the time of vehicle power-off is completed, a signal to that effect is output from the receiving IC 20 to the TPMS microcomputer 19, and based on this, the tire pressure monitoring operation is performed by the TPMS microcomputer 19. Good.

The vehicle power supply may take three positions of power off / IG on / engine start, or may take two positions of power off / power on.
The communication operation (one operation) of the electronic key system 3 that is synchronized with the tire pressure monitoring operation while the vehicle power is off is not limited to the wake signal transmission operation. For example, when challenge response authentication is imposed on smart verification, a wake signal and a response code may be transmitted, or a key number may be included therein. Moreover, it is good also as signals other than a wake signal.

A signal other than the smart reception request signal Scro can be used as a signal that becomes the power source of the reception IC 20 when the vehicle power is off.
-Three or more receiving antennas 23 may be sufficient.

Smart communication may be executed at any time, and does not particularly limit the execution timing.
The electronic key system 3 may set the radio wave to the same frequency on the communication outbound path and the return path.

  The electronic key system 3 determines the position of the electronic key 2 in and out of the vehicle by combining the response of the electronic key 2 to radio waves transmitted from these antennas, for example, by installing transmission antennas at the right and left parts of the vehicle body. However, ID verification may be performed.

The frequency used for the radio wave of the electronic key system 3 can be changed to other ones such as an LF band radio wave, for example. This is also true for the tire pressure monitoring system 7.
The electronic key system 3 may be a short-range wireless system that performs communication by using short-range wireless (communication distance: several centimeters to several tens of centimeters) of radio waves from the vehicle 1 to the power source of the electronic key 2. Examples of the short-range wireless system include an immobilizer system and an NFC (Near Field Communication) communication system.

The tire pressure monitoring system 7 may be a type in which the tire pressure sensor 5 executes radio wave transmission by an initiator attached to each tire 4.
The integrated receiver 18 may take the “TPMS communication mode” when inputting a pulse from the smart reception request signal Srco, and switch to the “smart communication mode” when no pulse is input.

  The difference between the “first smart communication mode” and the “second smart communication mode” may be such that, in addition to the frequency, these parameters such as a communication format, a baud rate, and a demodulation method may be different.

  The integrated receiver 18 takes the “second smart communication mode” when the pulse of the smart frequency switching signal Scsel is not inputted, and enters the “first smart communication mode” when the pulse of the smart frequency switching signal Scsel is inputted. It may be switched.

The smart reception request signal Srco and the smart frequency switching signal Scsel may be output from different ECUs.
-You may change an authentication control part to ECUs other than collation ECU8.

The operation state switching signal may be changed to another signal such as a TPMS reception request signal.
The operation state switching signal may be, for example, a request signal for switching a specific operation in the “TPMS communication mode” or a request signal for switching a specific operation in the “smart communication mode”.

  The vehicle 1 includes a hybrid vehicle, a plug-in hybrid vehicle, an electric vehicle, a fuel cell vehicle, etc. in addition to a gasoline vehicle.

  DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... Electronic key, 3 ... Electronic key system, 4 ... Tire, 5 ... Tire pressure sensor as a sensor part, 6 ... Vehicle body, 7 ... Tire pressure monitoring system, 8 ... Verification ECU as an authentication control part, DESCRIPTION OF SYMBOLS 18 ... Integrated receiver, 19 ... TPMS microcomputer as a tire pressure monitoring microcomputer, 20 ... Reception IC as a receiving circuit, 28 ... Power supply terminal, 31 ... Fuse, 32 ... Battery, 48 ... As vehicle power supply state monitoring means Power communication state monitoring unit 49... Communication synchronization processing unit as tire pressure monitoring execution means, Stp... Tire pressure signal, Srco... Smart reception request signal as operation state switching signal.

Claims (5)

Commonly used by an electronic key system that verifies the validity of an electronic key by wireless communication and a tire pressure monitoring system that wirelessly transmits a tire pressure signal from a sensor unit attached to a tire to the vehicle body and monitors the tire pressure in the vehicle body. In the integrated receiver
Vehicle power state monitoring means for monitoring the power state of the vehicle;
Tire pressure monitoring execution means for executing a tire pressure monitoring operation in synchronization with the communication operation of the electronic key system performed in this situation when the vehicle power is turned off ,
When the operation state switching signal is input from the authentication control unit that controls the operation of the electronic key system on the vehicle body side when the vehicle power is turned on, the operation mode becomes the electronic key system mode, and when the operation state switching signal is not input, It becomes the mode for tire pressure monitoring system,
The tire pressure monitoring execution means determines whether or not to execute the tire pressure monitoring operation by confirming whether or not the operation state switching signal is input when the vehicle power is off. Integrated receiver. 2. The integration according to claim 1, wherein the synchronization is a process of performing the tire pressure monitoring operation immediately after completion of one communication operation of the electronic key system that is repeatedly performed when the vehicle power is turned off. Receiving machine. 2. The integrated receiver according to claim 1, wherein the synchronization is a process of simultaneously performing one operation of communication of the electronic key system repeatedly performed when the vehicle power is turned off and an operation of monitoring the tire pressure. . A receiving circuit for demodulating the received radio wave, and a tire pressure monitoring microcomputer for controlling the operation of the tire pressure monitoring;
Power is supplied to the receiving circuit and the tire pressure monitoring microcomputer from a battery connected to its own power supply terminal via a fuse, and power of the battery is supplied to the authentication control unit from between the battery and the fuse. The operation state switching signal output from the authentication control unit is also supplied as a power source for the tire pressure monitoring microcomputer,
When the fuse is removed, the battery power is not supplied to the tire pressure monitoring microcomputer and the tire pressure monitoring system does not operate. However, the operation state switching signal is supplied to the receiving circuit as a power source. The integrated receiver according to any one of claims 1 to 3, wherein the integrated receiver operates as an electronic key system mode by being supplied. The integrated reception according to any one of claims 1 to 4 , wherein the communication operation is a polling operation for periodically confirming establishment of communication with the electronic key while the vehicle is parked or stopped. Machine.