JP2013203312A - Electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric vehicle in which reduction of air pressure can be monitored appropriately taking into account characteristics of an EV or PHEV needed to be charged.SOLUTION: An electric vehicle 1 includes an electric motor which is driven by power accumulated in a high voltage battery B1 and the electric motor is utilized as a driving source or a part of the driving source. The electric vehicle 1 includes a tire inflation pressure monitoring system 100 including an air pressure sensor unit 3 installed within a tire 2 and a monitoring unit 5 for monitoring reduction in tire inflation pressure from data about the air pressure of the tire 2 transmitted from the air pressure sensor unit 3. While the electric vehicle 1 is in an activated state and while the electric vehicle is in a non-activated state and the battery is connected with an external power source, the tire inflation pressure monitoring system 100 causes the air pressure sensor unit 3 to transmit the data about the air pressure of the tire 2, and monitors the reduction in air pressure of the tire 2.

Description

  The present invention relates to an electric vehicle equipped with a tire air pressure monitoring system that can easily identify a tire whose air pressure has decreased.

  There are two types of tire puncture: (1) the tire is damaged by a sharp object such as a nail, and the air pressure inside the tire rapidly drops and punctures. (2) The degree of damage is mild or the air pressure is increased. There are cases where the air pressure inside the tire gradually drops and punctures over a long time, such as deterioration of the valve to be injected. Of these, the puncture of type (2) (hereinafter referred to as “slow puncture”) was damaged by a sharp tire on the run just before returning home, but was parked in the parking lot because the degree was mild. The air pressure inside the tire has hardly decreased at that time, and then the air pressure inside the tire gradually drops, and when the car is driven again the next morning, the air pressure inside the tire may have dropped to a puncture state. .

  An air pressure sensor unit having a sensor for detecting tire air pressure is installed in the tire air chamber, and the tire air pressure data transmitted from the air pressure sensor unit to the vehicle body side monitoring unit is monitored to detect a decrease in the tire air pressure. There is a known vehicle equipped with a tire pressure monitoring system (TPMS) that notifies the driver of a decrease in tire pressure by turning on a warning lamp on the instrument panel of the vehicle when the amount exceeds a predetermined value. (Patent Document 1), in the United States, TPMS equipment has been gradually introduced, and since mid-2009, equipment on new cars has become completely obligatory.

In this TPMS, the air pressure in the tire is indirectly measured from the dynamic load radius of the wheel (tire) during traveling without directly using the above-mentioned air pressure sensor unit to directly measure the air pressure in the tire. There is an indirect type to measure, and the indirect type cannot measure the air pressure unless it is running. On the other hand, in the direct type, the air pressure sensor unit is operated by a battery, the monitoring unit is operated by a battery, and the tire pressure measured by the air pressure sensor unit is transmitted to the monitoring unit once every minute during driving. ing. Further, when the vehicle is not traveling, that is, when the IG (ignition) switch (start switch) is turned off, the operation of the air pressure sensor unit is suspended in order to prevent battery consumption.
Eventually, in both the direct and indirect methods, the TPMS cannot measure the air pressure when the IG switch is OFF, and thus cannot detect the above slow puncture.

JP 2010-241384 A

  By the way, in the case of the direct type TPMS, even when the IG switch is turned off, the data relating to the tire air pressure is transmitted from the air pressure sensor unit to monitor the decrease in the tire air pressure, so that the slow puncture is detected. be able to. On the other hand, it is also necessary to reduce the exhaustion of the built-in battery of the air pressure sensor unit and to make the air pressure sensor unit replacement interval as long as possible. In addition, since the TPMS is not operated by the air pressure sensor unit alone, that is, since the air pressure data transmitted from the air pressure sensor unit needs to be processed by the vehicle monitoring unit, the vehicle battery is consumed and the EV ( In the case of an Electric Vehicle) or PHEV (Plug-in Hybrid Electric Vehicle), there are problems such as shortening the distance in which EV travel is possible or making EV travel impossible.

  By the way, in the case of parking for a short time, slow puncture cannot be detected (the time is insufficient to detect stomp puncture). For this reason, in the case of such a short-time parking, from the viewpoint of preventing battery consumption, transmission of data related to the tire air pressure from the air pressure sensor unit is suspended so as not to monitor a decrease in tire air pressure. It is desirable to do. In addition, since slow puncture occurs when the user is away from the vehicle, it is desired not only to detect puncture but also to promptly notify the user away from the vehicle.

  Accordingly, an object of the present invention is to provide an electric vehicle capable of appropriately monitoring a decrease in air pressure in view of characteristics such as EV and PHEV that require charging.

  This invention which solved the above-mentioned subject is an electric vehicle provided with an electric motor driven with electric power stored in a battery, and using the electric motor as a drive source or a part of the drive source. The electric vehicle includes a tire pressure monitoring system including an air pressure sensor unit installed in the tire and a monitoring unit that monitors a decrease in tire air pressure from data related to the tire air pressure transmitted from the air pressure sensor unit. The tire air pressure monitoring system causes the air pressure sensor unit to transmit data related to tire air pressure when the electric vehicle is in an activated state and in a non-activated state and the battery is connected to an external power source. And monitoring the decrease in tire air pressure.

  That is, when the vehicle battery is connected to an external power source (when the normal charging cable is connected to the normal charging port as in the embodiment described later), the vehicle is normally parked for a long time such as at night. Therefore, a slow puncture can be detected. Moreover, even if the battery is not activated, it does not monitor the decrease in tire air pressure except when the battery is connected to an external power source. It is possible to prevent unnecessary consumption of the built-in battery of the air pressure sensor unit without transmitting data related to the air pressure of the tire. Furthermore, since the monitoring unit for monitoring the decrease in tire air pressure operates when the battery is connected to the external power supply, it is possible to prevent the battery from being consumed in the non-starting state.

  Further, in the present invention, the electric vehicle includes a communication device that performs information communication with the outside, and when the battery is connected to an external power source in a non-activated state, the tire air pressure monitoring system is When a decrease in air pressure is detected, information indicating that the tire air pressure is in a reduced state is transmitted from the communication device to the user of the electric vehicle.

  Even when the user is away from the electric vehicle, the user can know in advance that the tire air pressure is in a lowered state, and therefore, it is possible to take measures such as puncture repair with a margin.

  The present invention can provide an electric vehicle capable of appropriately monitoring a decrease in air pressure in view of characteristics such as EV and PHEV that require charging.

1 is a diagram showing an overall configuration of an electric vehicle according to a first embodiment of the present invention. It is a figure which shows the structure of the tire pressure monitoring knit mounted in the vehicle body side of the electric vehicle of FIG. It is a figure which shows the structure of the tire pressure sensor unit mounted in the wheel side of the electric vehicle of FIG. It is a figure which shows typically the structure by the side of the house at the time of charging the electric vehicle of FIG. 1 at home. 3 is a flowchart of control in the first embodiment. It is a time chart including malfunction to air pressure abnormality detection, (a) shows when the air pressure falls below the lower limit of the normal range of air pressure, and (b) shows when there is a sudden change in air pressure. It is a flowchart of control in a 2nd embodiment. It is a flowchart of control in a 3rd embodiment. It is a figure which shows the contact path | route to the user in 4th Embodiment. It is a figure which shows the modification of FIG.

≪First embodiment≫
Next, one mode for carrying out the present invention (hereinafter referred to as “embodiment”) will be described in detail with reference to the accompanying drawings.
FIG. 1 is a diagram schematically showing the overall configuration of an electric vehicle 1 according to the first embodiment of the present invention. The electric vehicle 1 is equipped with a tire pressure monitoring system 100.

  The electric vehicle 1 is a vehicle such as EV or PHEV, and is a four-wheel vehicle including four wheels 6FR (right front wheel), 6FL (left front wheel), 6RR (right rear wheel), and 6RL (left rear wheel). It is. Four tires 2FR, 2FL, 2RR, 2RL are mounted on the four wheels 6FR, 6FL, 6RR, 6RL, respectively.

  In the present embodiment, with reference to the traveling direction of the electric vehicle 1, the front right component is “FR”, the left front component is “FL”, the right rear component is “RR”, and the left rear A character string of “RL” is appended to the constituent elements of to indicate the arrangement positions of the constituent elements. When these components are collectively referred to, and when these components are not distinguished by their arrangement positions, they should be indicated by the main body part (numerical part) of the code without attaching the letters FR, FL, RR, RL. To do. In this case, for example, the tire 2 and the wheel 6 are described.

(Configuration of TPMS)
The tire air pressure monitoring system 100 is constructed in the electric vehicle 1 and promptly notifies the driver when the tire 2 has a decrease in air pressure. The tire air pressure monitoring system 100 includes components on the vehicle body side of the electric vehicle 1 and the wheel 6 side. It has the following components. The components on the wheel 6 side include a tire pressure sensor unit 3 (3FR, 3FL, 3RR, 3RL). The components on the vehicle body side include a tire pressure monitoring unit 5, an initiator 51A (51FR, 51FL, 51RR, 51RL), and a receiving antenna 52.
Hereinafter, the tire pressure sensor unit 3 and the tire pressure monitoring unit 5 will be described by appropriately omitting the letters “tire”.

  In order to directly measure the air pressure of the four tires 2FR, 2FL, 2RR, 2RL, each of the wheels 6FR, 6FL, 6RR, 6RL is provided with an air pressure sensor unit 3FR, 3FL, 3RR, 3RL.

The appearance of the air pressure sensor unit 3 is shown in the upper right of FIG.
The air pressure sensor unit 3 is a valve-integrated type, but a separate type can also be used. One end of the tire valve 37 is integrally fixed to the main body portion so as to open into an air hole 38 formed in the main body portion. The other end of the tire valve 37 is exposed to the outside of the rim (described later) and is provided with an air inlet, but a valve cap is usually fitted. A sensor hole 39 is also formed in the main body portion, and sensors built in the main body portion can measure the environment (pressure, temperature, etc.) in the tire 2.

  The air pressure monitoring unit 5 is an ECU (Electronic Control Unit), and includes a microcomputer and peripheral devices, and implements each function described later by installing a predetermined program in the microcomputer so as to be executable. The air pressure monitoring unit 5 is connected to an initiator 51A (51FR, 51FL, 51RR, 51RL), a receiving antenna 52, and an indicator 4.

  The initiators 51FR, 51FL, 51RR, 51RL are installed in tire houses containing the tires 2FR, 2FL, 2RR, 2RL, respectively, and are controlled by the air pressure monitoring unit 5 to the air pressure sensor units 3FR, 3FL, 3RR, 3RL, for example. A command signal is transmitted by an amplitude-modulated magnetic field (LF wave) having a frequency of 125 kHz.

  FIG. 2 is a diagram showing a configuration of the air pressure monitoring unit 5 mounted on the vehicle body side of the vehicle. As shown in FIG. 2, the air pressure monitoring unit 5 includes a microprocessor 50 that performs calculation and control in the air pressure monitoring unit 5, an initiator 51A (wireless transmission unit 51), a reception antenna 52A (wireless reception unit 52), A CAN (Controller Area Network) adapter 53 and a PLC (Power Line Communications) adapter 54 are provided. Among these, the microprocessor 50 includes a CPU 501, a main storage unit 502, an auxiliary storage unit 503, an input / output interface (I / O) 504, and an analog / digital converter (AD) 505. The air pressure monitoring unit 5 operates using an in-vehicle 12V battery B2 as a power source.

In the present embodiment, there are three command signals to be transmitted by LF waves from the air pressure monitoring unit 5 to the air pressure sensor unit 3 through the initiator 51A: “start command”, “pause command”, and “transmission command”. These three command signals are originally provided in the tire pressure monitoring system 100.
Among these, the “startup command” is a command signal for starting up the air pressure sensor unit 3 that is at rest. The “pause command” is a command signal for pausing the activated air pressure sensor unit 3. The “transmission command” is a command signal for forcibly returning one monitoring data to the activated air pressure sensor unit 3.

  The “start command” is transmitted through the initiator 51A when the IG switch (start switch) of the electric vehicle 1 is turned on. The “pause command” is transmitted through the initiator 51A when the ignition switch of the electric vehicle 1 is turned off.

  The inactive air pressure sensor unit 3 is activated when it receives an “activation command” via the receiving antenna 31A and enters an operating state. During the operation state, the air pressure sensor unit 3 transmits monitoring data every time a built-in transmission timer (not shown) measures a predetermined time (for example, 1 minute). That is, the air pressure sensor unit 3 autonomously transmits monitoring data (the built-in battery 35 is consumed). On the other hand, when the “pause command” is received, the air pressure sensor unit 3 in the operating state is put into a pause state. During the sleep state, the air pressure sensor unit 3 stops the operation of other functions except for the minimum function for receiving the start command and starting again (consumption of the built-in battery 35 is prevented / suppressed). In addition, when a “transmission command” is received, the air pressure sensor unit 3 returns monitoring data each time, regardless of the timing of the transmission timer. At the same time, the transmission timer of the air pressure sensor unit 3 is reset and starts counting again from zero. Incidentally, the air pressure sensor unit 3 that forcibly returns a plurality of monitoring data, for example, may return two monitoring data continuously by one reply.

  In the present embodiment, when the air pressure monitoring unit 5 determines that it takes a long time until the ignition switch is turned on next time when the ignition switch is turned off, the air pressure monitoring unit 5 Air pressure is monitored by By the way, whether or not it is a long time is determined by whether or not normal charging is performed (performed), and monitoring is performed when long-time charging is performed by normal charging. Specifically, as will be described later, when the battery control unit BC is notified (connection notification) that the charging cable Ca is connected (plug-in) to the normal charging port P1, the air pressure monitoring unit 5 The air pressure is monitored at an interval (1 hour) longer than the interval during travel (1 minute). Details on this point will be described later.

  The receiving antenna 52 has a function of receiving monitoring data transmitted from the air pressure sensor units 3FR, 3FL, 3RR, 3RL, for example, by radio waves (RF waves) in the UHF band (ultra-high frequency band) and sending the monitoring data to the air pressure monitoring unit 5. .

  The air pressure monitoring unit 5 has a function of demodulating the monitoring data and extracting the monitoring data. One frame of monitoring data includes a sensor ID and measurement data (air pressure data, temperature data, etc.). The sensor ID is very unique data (unique in many electric vehicles 1), and the sensor IDs of the air pressure sensor units 3FR, 3FL, 3RR, 3RL are registered in the air pressure monitoring unit 5 in advance.

  The indicator 4 is a display device that performs display according to the control of the air pressure monitoring unit 5. As shown in the indicator display example 40, when a tire abnormality such as a decrease in the air pressure of the tire 2 is detected, the tell tale 43 in which the “!” Mark is combined with the cross-sectional shape of the tire 2 is yellow according to the control of the air pressure monitoring unit 5. And the portion corresponding to the tire 2 corresponding to the vehicle-shaped symbol 41 is lit in yellow to notify the driver. When any system abnormality occurs in the tire pressure monitoring system 100, the “TPMS” tell tale 44 is lit in yellow.

  Incidentally, the air pressure monitoring unit 5 is connected to the indicator 4 and the battery control unit BC via the CAN adapter 53 by CAN. Further, when the charging cable Ca is connected to the normal charging port P1, the air pressure monitoring unit 5 is connected to the indoor monitor 300 and the PLC via the PLC adapter 54 as a communication device. By the way, the connection path by the PLC is the air pressure monitoring unit 5 ⇔ vehicle-mounted charger Cg ⇔ charging cable Ca ⇔ outer wall outlet 107 ⇔ domestic electric cable (distributor 203) ⇔ PLC adapter 204 ⇔ indoor monitor 300.

FIG. 3 is a block diagram showing the air pressure sensor unit 3 in detail.
The air pressure sensor unit 3 includes a microprocessor 30 that performs calculation and control in the air pressure sensor unit 3, a reception antenna 31A that receives a signal (LF wave) from the initiator 51A, and a wireless reception unit that demodulates a reception signal from the reception antenna 31A. 31, a wireless transmission unit 32 that modulates transmission data from the microprocessor 30, a transmission antenna 32 </ b> A that transmits a transmission signal from the wireless transmission unit 32 to the reception antenna 52 of the air pressure monitoring unit 5, and the tire 2 To each part of the air pressure sensor unit 3 including the microprocessor 30, the pressure sensor 33 that outputs the air pressure of the air as a physical quantity such as a capacitance, the temperature sensor 34 that outputs the temperature in the tire 2 as a physical quantity such as a resistance value, and the like. And a battery 35 for supplying electric power. Since these are the same as in Patent Document 1, description thereof is omitted.

(Configuration of electric vehicle)
The electric vehicle 1 according to the present embodiment shown in FIG. 1 is a vehicle such as EV or PHEV as described above, and includes the high-voltage battery B1, the inverter and the travel motor (not shown), and illustrates the DC power stored in the high-voltage battery B1. It converts into alternating current with the inverter which does not drive, drives the driving motor which is not illustrated, and it travels. As shown in FIG. 1, the electric vehicle 1 includes an in-vehicle charger Cg that converts AC power into DC power, and the high-voltage battery B1 is charged by single-phase 100 V or 200 V AC power from a household outlet. Is done. Incidentally, in the case of quick charge from the quick charger, the battery is charged without going through the on-vehicle charger Cg.
The electric vehicle 1 includes a charging lid, and a normal charging port P1 for normal charging and a quick charging port P2 for quick charging are provided in the lid.

  The high-voltage battery B1 is, for example, a large-capacity assembled battery in which a large number of lithium ion secondary cells are connected in parallel and in series. A vehicle-mounted charger Cg is connected to the normal charging port P1, and AC power (single-phase AC 200V) from the outlet 107 divided by the distribution board 103 (FIG. 4) in the house described later is supplied. It has a function of boosting and converting to direct current, and charging the high-voltage battery B1 with the converted direct-current power. The on-vehicle charger Cg of this embodiment shall fully charge the high voltage battery B1 in about 8 hours. Moreover, the quick charge port P2 is connected to the high voltage battery B1 via a contactor (not shown), and rapidly charges the high voltage battery B1 without converting current or voltage.

  Symbol BC is a battery control unit, and has a function of controlling charging / discharging of the high voltage battery B1. As described above, the battery control unit BC is connected to the air pressure monitoring unit 5 by CAN.

Charging the electric vehicle 1 includes “rapid charging” using a quick charger and “normal charging” using a power line (single-phase 100 V, single-phase 200 V) in a house.
In the case of fast charge, it can be charged in about 30 minutes to about 80% of full charge, in the case of single-phase 100V normal charge, it can be charged in about 16 hours until full charge, and in single-phase 200V normal charge (double speed charge) It can be charged in about 8 hours until charging. Incidentally, a single-phase 200V battery is sometimes referred to as “double speed charging”.

  CHAdeMO (registered trademark), which is one of the standards for quick charging, connects a charging cable for a quick charger to a quick charging port of a vehicle, and performs quick charging with DC power supplied from the quick charger. . On the other hand, in the case of charging by household single-phase 100V or 200V, the outlet of the house and the normal charging port P1 of the electric vehicle 1 are connected by the cable Ca (see FIG. 4), and normal charging is performed with AC power. In the case of quick charging by CHAdeMO, the electric vehicle 1 and the quick charger are connected by CAN (Controller Area Network) communication, and charging is performed while the electric vehicle 1 and the quick charger are communicating. On the other hand, in the case of charging using a household outlet, the electric vehicle 1 includes an in-vehicle charger (AC / DC converter) Cg that converts alternating current into direct current, and converts alternating current power into direct current power for charging.

  In addition, since a quick charger is expensive and requires a large amount of power, it is generally installed in a charging stand of a business operator. Since the electric vehicle 1 is often equipped with an ordinary charger such as the on-vehicle charger Cg, the electric vehicle 1 can be charged anywhere where there is a single-phase 100V or single-phase 200V outlet. As described above, the electric vehicle 1 according to the present embodiment includes the normal charging port P1 and the quick charging port P2, and includes the on-vehicle charger Cg for normal charging. 100V or single phase 200V) can be charged normally.

(Composition on the housing side)
FIG. 4 is a diagram schematically showing a configuration on the house side when the electric vehicle 1 is charged at home. As shown in FIG. 4, the electric power line of the system from the pole transformer (not shown) is drawn into the house through the watt-hour meter 101 and the blocking filter 102 as a lead-in line for a single-phase three-wire distribution line. . The blocking filter 102 is a low-pass filter that prevents a PLC communication signal that leaks out of the house from leaking out of the house or prevents a PLC communication signal that leaks from a neighboring house from entering the house. It is a filter.

  The distribution board 103 divides the power from the grid. In the example of FIG. 4, the single-phase 100V indoor outlets 105a and 105b, the single-phase 200V outlet 106, and the single-phase 200V outer wall outlet 107 on the outer wall of the house are separated through the breaker 104, respectively. Electricity. Among these, the indoor outlet 105a is divided from the L1 phase and the neutral line, and the indoor outlet 105b is divided from the L2 phase and the neutral line. Both the indoor outlet 106 and the outer wall outlet 107 are divided from the L1 phase and the L2 phase. Among these, the outer wall outlet 107 is used for charging the electric vehicle 1.

  In addition, as a network in the house, a router 201, a PLC adapter 202, a distributor 203, and a PLC adapter 204 are provided so that communication via the Internet IN can be performed and communication with the electric vehicle 1 can be performed.

  The indoor monitor 300 is a device having a function of notifying the user of the charging status of the high-voltage battery 1 of the electric vehicle 1, and is, for example, a personal computer or a dedicated terminal.

(Operation)
The operation of the electric vehicle 1 described above will be described. First, the operation when the IG switch is ON will be described, and then the operation when the IG switch is OFF will be described. The operation when the IG switch is OFF will be described with reference to the flowchart of FIG.

(When IG switch is ON (when electric vehicle 1 is started))
In the electric vehicle 1, when the IG switch is turned on, the air pressure monitoring unit 5 is activated and transmits an “activation command” to the air pressure sensor unit 3 via the initiator 51 </ b> A to activate the air pressure sensor unit 3. When the air pressure sensor unit 3 is activated, the air pressure sensor unit 3 itself monitors the air pressure, and autonomously once a minute (and when the pressure suddenly changes), the air pressure data is sent to the air pressure monitoring unit 5 via the antenna 32A. And send. The air pressure monitoring unit 5 acquires air pressure data via the receiving antenna 52A, determines the decrease in air pressure, and displays the determination result on the indicator 4.

(When IG switch is OFF and plug-in)
When the IG switch is turned off (when the electric vehicle 1 is not started), as described above, the air pressure monitoring unit 5 transmits a “pause command” to the air pressure sensor unit 3 via the initiator 51A, and the air pressure sensor unit 3 To pause. As a result, the air pressure sensor unit 3 is stopped with only a minimum function, and the consumption of the internal battery 35 is suppressed. Moreover, the air pressure monitoring unit 5 itself is also stopped to suppress the consumption of the 12V battery B2. When the IG switch is turned on again, the air pressure monitoring unit 5 is restarted as described above.

  If the time from when the IG switch is turned off to when it is turned on is short, for example, when the time until it is turned on is short as in the case of quick charge, the puncture (slow puncture) described in (2) above is performed. Although there is not much need to detect it, it is desirable to detect a slow puncture and notify the user if the time until it is turned on is long. However, if the air pressure monitoring unit 5 is started all the time when the IG switch is turned off, the air pressure monitoring unit 5 itself and the air pressure sensor unit 3 consume power, so the 12V battery B2 is consumed and the built-in battery 35 is consumed. It will expedite the exhaustion. Even if the 12V battery B2 is charged by the high voltage battery B1, the consumption of the high voltage battery B1 is accelerated. For this reason, it may be necessary to replace the built-in battery 35, or the electric vehicle 1 cannot be started when the IG switch is turned on due to exhaustion of the high voltage battery B1 or the 12V battery B2.

Therefore, in the present embodiment, processing according to the flowchart of FIG. 5 is performed.
The battery control unit BC and the air pressure monitoring unit 5 are put into a sleep mode in which only a minimum function is left and power consumption is suppressed by turning off the IG switch, and the built-in battery 35, the high voltage battery B1, the 12V battery B2, and the like are consumed. Shall be suppressed.

In this state (sleep mode), the battery control unit BC determines whether or not the normal charging cable Ca is connected to the normal charging port P1 of the electric vehicle 1 (plugged in or not) as the minimum function. Is monitored (step S11). The presence / absence of connection can be determined by voltage monitoring, a microswitch signal (not shown), or the like. If there is no connection to the normal charging port P1, the connection is waited (step S11 → No). When the cable Ca is connected (step S11 → Yes), the battery control unit BC transmits a connection notification to the air pressure monitoring unit 5 (step S12). That is, the tire pressure monitoring unit 5 monitors the presence / absence of a connection notification as the minimum function. As a result, the air pressure monitoring unit 5 is activated and transmits an “activation command” via the initiator 51A.
As will be described later, the processing in step S11 and step S12 can be omitted.

  Incidentally, the connection (plug-in) of the cable Ca and the charging (start of charging) to the high voltage battery B1 are not directly related. For example, charging may be started in the midnight power time zone (from 23:00) by a timer, and charging may be started by a user operation with a switch (not shown). In this embodiment, apart from whether or not charging is actually started, it is assumed that the electric vehicle 1 is left unattended for a long time by connecting the cable Ca for normal charging (2). Puncture monitoring.

  The battery control unit BC determines whether charging has started (step S13). Note that the processing in step S13 can also be omitted. When charging is started (step S13 → Yes), the battery control unit BC monitors the charging status (step S14). The monitored charging status may be kept inside, for example, sent to the air pressure monitoring unit 5 by CAN, and the air pressure monitoring unit 5 may send it to the indoor monitor 300 by PLC. Here, it is assumed that the monitored charging state is kept inside the battery control unit BC.

  The battery control unit BC determines whether or not the battery is fully charged (step S15). If the battery is not fully charged (step S15 → No), the monitoring in step S14 is continued. When the battery is fully charged (step S15 → Yes), for example, the charging by the on-vehicle charger Cg is terminated, and the open-circuit voltage of the high voltage battery B1 and the SOC (State Of Charge) at the time of full charging are stored in the memory. A charge termination process such as storing is performed (step S16).

Thereafter, it is monitored whether the cable Ca connected to the normal charging port P1 is released (step S17). If not canceled (step S17 → No), the monitoring is continued. When released (step S17 → Yes), a release notification is sent to the air pressure monitoring unit 5 by CAN.
In a state where the cable Ca remains connected to the normal charging port P1, the electric vehicle 1 does not travel, and it can be considered that the state of being stopped (a state of being left for a long time) continues. On the other hand, when the cable Ca is released, it can be considered that the electric vehicle 1 is running (IG switch ON), in other words, it can be considered that there is no need to monitor the slow puncture. Notify as a notification.
After the cancellation notification in step S18, the battery control unit BC returns to the sleep mode in order to suppress power consumption.

  Upon receiving the connection notification (Step S12) from the battery control unit BC, the air pressure monitoring unit 5 transmits an “activation command” to the air pressure sensor unit 3 via the initiator 51A (Step S21). As a result, the air pressure sensor unit 3 is activated to measure the air pressure, and the measured air pressure is transmitted to the air pressure monitoring unit 5 via the antenna 32A. The air pressure monitoring unit 5 receives air pressure data via the receiving antenna 52A, and determines whether the air pressure is equal to or less than a specified value (step S22) or whether the difference from the previous air pressure is large (step S23). When the air pressure monitoring unit 5 can execute the process of step S22 and the process of step S23, that is, if both step S22 and step S24 are No in the flowchart of FIG. As well as "." By sending this “pause command”, the consumption of the internal battery 35 of the air pressure sensor unit 3 is suppressed. The case where Steps S22 and S23 are Yes, that is, the case where the air pressure is abnormal will be described later.

  By the way, the air pressure sensor unit 3 transmits data every minute in the same way as usual by the “start command”, so that the air pressure data is not transmitted many times (so that the built-in battery 35 is not consumed) The processes in steps S21 to S24 are preferably finished in the minimum necessary short time (less than 1 minute), and the air pressure sensor unit 3 is quickly stopped. Note that step S24 may be executed before steps S22 and S23 as long as the processing of steps S22 and S23 can be executed by receiving the air pressure data.

  When the air pressure sensor unit 3 is stopped by the process of step S24, the timer waits for one hour to elapse (step S25). This time of 1 hour is a standby time set appropriately from the viewpoint of suppressing the consumption of the internal battery 35 and the 12V battery B2 (and also the high voltage battery B1), and is not limited to 1 hour. Incidentally, the air pressure sensor unit 3 and the air pressure monitoring unit 5 consume more power when oscillating LF waves and RF waves. During this one hour, the air pressure sensor unit 3 does not oscillate the RF wave via the transmitting antenna 32A, so that the consumption of the built-in battery 35 is suppressed, and the air pressure monitoring unit 5 also performs LF via the initiator 51A. Since no wave oscillation is performed, consumption of the 12V battery B2 is suppressed.

  When the timer counts the lapse of 1 hour (standby time) (step S25), the process returns to step S21 and the same processing is repeated, but before that, whether or not the release of the cable Ca has been notified from the battery control unit BC. Is determined in step S26. When there is no cancellation notification (step S26 → No), the process returns to step S21, and the air pressure sensor unit 3 is activated again.

  If there is a release notification (step S26 → Yes), since the cable Ca is released from the normal charging port P1, it can be considered that the electric vehicle 1 is close to travel, that is, the puncture monitoring described in (2) above is necessary. Therefore, the stop process is performed (step S29), and the process returns to the sleep mode.

Here, if any of Steps S22 and S23 is No, that is, if the air pressure is abnormal, the air pressure abnormality is notified to the indoor monitor 300 (air pressure abnormality notification). A sound (voice) is generated and notified to the user (step S27).
This air pressure abnormality notification is routed through the air pressure monitoring unit 5 ⇒ in-vehicle charger Cg ⇒ charging cable Ca ⇒ outer wall outlet 107 ⇒ residential power line (distributor 203) ⇒ PLC adapter 204 ⇒ indoor monitor 300.
Since the air pressure sensor unit 3 is in the activated state, it is paused in the same manner as the processing in step S24 (step S28).

  FIG. 6 is a time chart from failure occurrence to air pressure abnormality detection, where (a) shows when the air pressure falls below the lower limit of the normal air pressure range, and (b) shows when there is a sudden air pressure change. Yes.

  In FIG. 6A, a slow puncture occurs due to a stepping on a nail during driving (problem occurrence). Then, after a while, the electric vehicle 1 is stopped and plugged in. That is, the cable Ca is connected to the normal charging port P1 (step S11 → Yes). Then, the air pressure sensor unit 3 is immediately activated (step S21), and the air pressure is monitored according to the flowchart of FIG. In this example, the air pressure is monitored every hour, the first time, the second time, the third time, and the air pressure is in the normal range up to the fifth time. When the fifth time has passed, the air pressure falls below the lower limit of the normal range (below the specified value). This, that is, abnormal air pressure is detected by the sixth monitoring (step S22 → Yes).

  In FIG. 6B, up to the third time, which is the same as the example of FIG. 6A, the air pressure suddenly decreased for some reason between the third and fourth times. Therefore, the difference between the third measurement value and the fourth measurement value is large (the difference in air pressure from the previous time is large), and the air pressure is in the normal range, but the air pressure abnormality is detected for the fourth time (step S23 → Yes).

(Effect etc.)
According to the embodiment described above, when the electric vehicle 1 is in the non-starting state (when the IG switch is OFF), the slow puncture is monitored on the condition that the normal charging cable Ca is connected. In this way, by setting charging as a condition, it is possible to exclude a short stop from the object of monitoring for slow puncture, and by setting normal charging as a condition, from the object of monitoring for slow puncture, It is possible to exclude those that are expected to be parked for a short time, such as quick charging, and can also exclude long-time parking that is left for days or weeks. That is, when the normal charging cable Ca is connected, it is possible to appropriately monitor the slow puncture in the situation where the electric vehicle 1 is driven again in about 8 to 16 hours.

  Further, even when the tire of the parked electric vehicle 1 is in the state of traveling immediately before a nail or the like is stuck and the air slowly leaks, the change in the air pressure is recognized, and an information output destination that is set in advance (first embodiment) Then, the air pressure drop information is transmitted to the indoor monitor 300), and it is in a place away from the electric vehicle 1 (the indicator 4 in the vehicle compartment) that the air pressure drop leading to the puncture is in progress or already in the puncture state. By telling the user, the next time the electric vehicle 1 is used, it is possible to request repairs to a repairer in advance, and there is room to change the schedule due to the occurrence of tire repair time before the next operation. Can respond.

In other words, it is generally noticed only the next time you drive the car, or you can notice the puncture after becoming a puncture event. On the other hand, it is possible to have a relaxed response and a planned repair response before the next operation.
In addition, punctures caused by mischief during charging (parking for a long time) can be determined while parking, and planned repairs for the next operation are possible.
In addition, the air pressure detection (transmission) interval during charging (parking for a long time) is longer than the detection (transmission) interval during normal operation, so air pressure detection (transmission) during charging (parking for a long time) ), The consumption of the built-in battery 35 incorporated in the air pressure sensor unit 3 can be kept small, and for example, the labor and cost of replacing the built-in battery 35 can be reduced.

  In addition, although it demonstrates using the house in FIG. 4, it is clear that this invention is not implemented limiting to a house, and a parking lot provided as a commercial parking lot or a customer service The present invention can be applied to charging in a parking lot of a company office, etc. (this point is the same in the following embodiments).

<< Second Embodiment >>
Next, a second embodiment of the present invention will be described. In addition, about the part which overlaps with 1st Embodiment, the duplicate description in 2nd Embodiment is abbreviate | omitted suitably, referring the figure in 1st Embodiment.

  FIG. 7 is a flowchart of control in the second embodiment. In the second embodiment, at the time of plug-in, that is, when the normal charging cable Ca is connected to the normal charging port P1 of the electric vehicle 1, the battery control unit BC and the air pressure monitoring unit are supplied with electric power supplied from inside the house. The power feeding system is configured so that 5 is automatically activated. For this reason, Steps S11 and S12 (and Step S13) in the flowchart of FIG. 5 are omitted for the battery control unit BC.

  For the air pressure monitoring unit 5, “pneumatic sensor unit pause” in step S24 in the flowchart of FIG. 5 is omitted. For this reason, in the second embodiment, the air pressure sensor unit 3 transmits air pressure data to the air pressure monitoring unit 5 once a minute, as in normal times. At this time, the air pressure sensor unit 3 uses the power of the built-in battery 35. However, since the air pressure sensor unit 3 is stopped by the “air pressure sensor unit pause” in step S28a, the internal battery 35 is consumed only when the cable Ca is connected. In this respect, it can be said that the consumption of the internal battery 35 is suppressed compared to the case where data is always transmitted during parking.

Further, since the battery control unit BC and the air pressure monitoring unit 5 are operated by electric power supplied from inside the house, the 12V battery B2 (and the high voltage battery B1) is not consumed. For this reason, when the IG switch is turned on, the occurrence of troubles due to a voltage drop is suppressed.
In the second embodiment, the air pressure sensor unit 3 transmits air pressure data once a minute as usual, but once in an hour as in the first embodiment. You can also. This point will be described in “Other Modifications”.

«Third embodiment»
A third embodiment of the present invention will be described. In addition, about the part which overlaps with 1st Embodiment or 2nd Embodiment, the description in 3rd Embodiment is suitably abbreviate | omitted as referring the figure in 1st Embodiment or 2nd Embodiment. .

  FIG. 8 is a flowchart of control in the third embodiment. In the third embodiment, the air pressure sensor unit 3 has a “long interval transmission mode” that autonomously transmits air pressure data at an interval longer than once per minute (for example, once an hour). ing. On the other hand, in addition to the above-mentioned three commands “start command”, “pause command”, and “transmission command”, the air pressure monitoring unit 5 performs “start command” in “long interval transmission mode” or starts It has a “mode shift command” for shifting to transmission in the “long interval transmission mode” for the air pressure sensor 3 inside.

As shown in FIG. 8, the air pressure monitoring unit 5 transmits the “start command” in the “long interval transmission mode” to the air pressure sensor unit 3 via the initiator 51A in step S21a, for example, 1 per hour. It is activated by sending air pressure data at intervals.
Before stopping, the air pressure sensor unit 3 is paused in step 28a by a “pause command”. For this reason, steps S24 and S25 in the first embodiment are omitted.
Incidentally, before step S21a, the “start command” is transmitted in the same manner as in the first embodiment, and then the “mode shift command” is transmitted to change the mode of the air pressure sensor unit 3. Needless to say, it is good.

According to the third embodiment, by adding a simple function to the air pressure sensor unit 3, air pressure data is transmitted autonomously, for example, once an hour. As a result, the air pressure monitoring unit 5 can reduce the number of operations of the initiator 51 </ b> A as compared with the first embodiment. Moreover, the air pressure sensor unit 3 can reduce the number of transmissions compared to the second embodiment. For this reason, consumption of the internal battery 35 and the 12V battery B2 can be suppressed.
Needless to say, the idea of the third embodiment can be easily applied to the second embodiment (the number of transmissions can be reduced).

<< Fourth Embodiment >>
A fourth embodiment of the present invention will be described. In addition, about the part which overlaps with 1st Embodiment-3rd Embodiment, the overlapping description in 4th Embodiment is abbreviate | omitted suitably, referring the figure in each embodiment.

  FIG. 9 is a diagram showing a contact route to the user in the fourth embodiment. As shown in FIG. 9, the tire pressure monitoring unit 5 includes a wireless LAN device 55 instead of the PLC adapter 54 of the first embodiment in FIG. 3. In the fourth embodiment, the wireless LAN device 55 can access the access point and communicate with the indoor monitor 300 in the house via the Internet IN. It can also communicate with a smartphone or the like via a base station or the like. That is, the air pressure abnormality notification in step S27 can be performed on the smartphone.

≪Other modifications≫
In the first embodiment, as shown in FIG. 6B, even if the air pressure suddenly decreases, the air pressure sensor unit 3 is autonomous when the pressure suddenly decreases. Alternatively, data may be transmitted to the air pressure monitoring unit 5. For example, it can be used to prevent mischief.
Moreover, although communication with the electric vehicle 1 and the house was demonstrated as an example which performs PLC (light line communication), it replaces with PLC and communication by CAN may be sufficient. Moreover, you may make it display a charge condition on the indoor monitor 300 also in PLC or CAN. The charging status can also be monitored by installing an ammeter / voltmeter in the house.
Further, in the flowchart of FIG. 5 and the like, if there is a release notification in step S18, the air pressure monitoring unit 5 may proceed as an interrupt process without waiting for the elapse of the timer in step S25.

  Moreover, although 2nd Embodiment of FIG. 7 has shown the example which detects an air pressure once per minute like usual, in the air pressure monitoring unit 5 in this 2nd Embodiment, it supplies from a house. When the power source (external power source) activates itself, and when the power source is activated from the external power source, the air pressure is increased, for example, once an hour by step S24 and step S25 as in the first embodiment. May be detected. By doing so, it is possible to suppress the consumption of the internal battery 35 of the air pressure sensor unit 3. Incidentally, whether or not it has been activated by an external power supply can be known by connection notification from the battery control unit BC (by providing step S12 as in FIG. 5). Further, the air pressure monitoring unit 5 can be detected by providing two connection ports for the power source, such as for the 12V battery B2 and for the external power source, or by other means.

Moreover, although the example in which the electric vehicle 1 is equipped with the on-vehicle charger Cg is shown, for example, as shown in FIG. 10, a normal charger 120 is provided in a home or the like, and the direct current supplied from the normal charger 120 is provided. Ordinary charging may be performed on the high voltage battery B1 by electric power. In the example of FIG. 10, the ordinary charger 120 is provided with an indoor monitor 300. In this case, a direct current flows through the cable Ca.
Further, for example, in the flowchart of FIG. 5, after the end of charging (after the disconnection of the cable Ca), there is a high possibility that the IG switch will be turned on without much time elapse. May be omitted.
Further, the first embodiment to the fourth embodiment can be implemented in appropriate combination.
Further, the present invention can be applied to any fuel cell vehicle as long as the high voltage battery B1 is mounted and normally charged (plug-in charging).
The 12V battery B2 is not essential, and low pressure (12V) power may be supplied from the high voltage battery B1 to the air pressure monitoring unit 5 via the step-down converter.
Further, when the normal charging cable Ca is connected to the normal charging port P1, a configuration in which the air pressure monitoring unit 5 is operated by an external power source via the cable Ca is preferable, but this configuration is not essential. Needless to say. Incidentally, when operating with the internal power source of the electric vehicle 1 such as the 12V battery B2 instead of the external power source, as a part of the “charging end processing” of step S16 in FIG. 5, the air pressure monitoring unit 5 (and the air pressure sensor unit 3) may be stopped.

DESCRIPTION OF SYMBOLS 1 Electric vehicle 2 Tire 3 Air pressure sensor unit 4 Indicator 5 Air pressure monitoring unit (monitoring unit)
54 PLC adapter (communication device)
55 Wireless LAN adapter (communication device)
100 Tire pressure monitoring system 107 Outer wall outlet (external power supply)
300 Indoor monitor B1 High voltage battery (battery)
B2 12V battery Ca cable Cg Car charger

Claims (2)

An electric vehicle comprising an electric motor driven by electric power stored in a battery, wherein the electric motor is a drive source or a part of the drive source,
The electric vehicle includes an air pressure sensor unit installed in a tire,
A tire pressure monitoring system having a monitoring unit for monitoring a decrease in tire pressure from data relating to tire pressure transmitted from the air pressure sensor unit;
The tire pressure monitoring system causes the air pressure sensor unit to transmit data related to tire air pressure when the electric vehicle is in an activated state and in a non-activated state and the battery is connected to an external power source. An electric vehicle characterized by monitoring a decrease in tire air pressure.   The electric vehicle includes a communication device that performs information communication with the outside, and the tire pressure monitoring system detects a decrease in tire air pressure when the battery is not activated and the battery is connected to an external power source. The electric vehicle according to claim 1, wherein information indicating that the tire air pressure is in a lowered state is transmitted from the communication device to a user of the electric vehicle.