JP2005301549A - Wheel condition monitoring system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique capable of accurately identifying which wheel is related to data transmitted from a wheel to an ECU or the like.
A wheel acceleration / deceleration sensor 30, a noise detection device 32, a transmitter 40, and a transmission antenna 50 are mounted on each wheel 20 of the vehicle 10. The detection result of the wheel acceleration / deceleration sensor 30 and the detection result of the noise detection device 32 are transmitted by the transmitters 40 and the transmission antennas 50, and are received by the reception antennas 52 and the receivers 42 mounted on the vehicle body 12, and the ECU 60 Sent to. Based on the detection value of the noise detection device 32, the ECU 60 identifies the wheel on which the wheel acceleration / deceleration sensor 30 corresponding to the noise detection device 32 is provided.
[Selection] Figure 1

Description

  The present invention relates to a wheel state monitoring system for monitoring a predetermined state of a wheel.

  When data such as a detection value of a wheel state detection sensor mounted on a wheel is transmitted to an electronic control device (hereinafter referred to as “ECU”) mounted on a vehicle body, the data transmitted to the ECU or the like is It is necessary to determine which wheel is related to the data.

As a technique for identifying each wheel, for example, a receiving antenna provided on the vehicle body side is arranged so as to be biased forward, backward, left, and right, and each wheel state detection sensor is mounted from the difference in intensity of radio waves received by this receiving antenna. A method has been proposed for identifying a wheel. In addition, a method has been proposed in which each wheel state detection sensor is characterized with respect to a voltage pattern of radio waves and a wheel is specified based on the voltage pattern (see, for example, Patent Document 1). In addition, various other methods have been conventionally proposed (see, for example, Patent Document 2, Patent Document 3, and Patent Document 4).
JP 2003-175711 A JP 2002-230676 A JP 2003-159920 A JP 2003-165317 A

  When adopting a method of identifying a wheel from a difference in radio wave intensity, it is necessary to strictly adjust the magnitude of the radio wave output. In particular, when the range in which the receiving antenna can be arranged is limited, for example, only in a vehicle, it is difficult to provide the receiving antenna with a large bias in the front, rear, left, and right. It may be difficult to accurately receive the intensity of. Moreover, since the intensity of the radio waves transmitted from each wheel is generally weak, it may be difficult to make a clear difference in the intensity of the radio waves.

  On the other hand, when adopting a method of identifying a wheel based on a voltage pattern, the voltage pattern may change relatively easily if the radio wave transmitted from each wheel is irregularly reflected. Therefore, depending on the environment when the vehicle is traveling, the voltage pattern of the actually transmitted radio wave may not match the voltage pattern of the actually received radio wave. Therefore, the method of identifying the wheel based on the voltage pattern of the radio wave is easily influenced by the environment and is not necessarily a highly accurate method depending on the traveling environment.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a wheel state monitoring system capable of accurately determining which wheel data is transmitted to an ECU or the like. And

  One aspect of the present invention relates to a wheel state monitoring system that monitors wheel states. This wheel state monitoring system is provided on a wheel and detects a predetermined amount of state, and a state amount detecting unit provided to correspond to the state amount detecting unit, and detects noise emitted from a noise generation source. Detecting means; and wheel specifying means for specifying the wheel provided with the state quantity detecting means corresponding to the noise detecting means based on a detection result of the noise detecting means.

  According to the wheel state monitoring system, the wheel provided with the state quantity detection unit can be accurately identified from the detection result of the noise detection unit provided so as to correspond to the state quantity detection unit. As a result, even when a signal transmitted from a transmission means provided on a plurality of wheels is received by a single reception means, it is possible to accurately determine which wheel the data included in the signal relates to. It can be specified. Here, the state quantity detection means can include all of those that detect a state quantity related to the vehicle, and includes, for example, a means that detects the rotational acceleration / deceleration of the wheel.

  Wheel-side communication means provided on the wheel for wirelessly transmitting the detection result of the state quantity detection means and the detection result of the noise detection means provided so as to correspond to the state quantity detection means, and the wheel attached A vehicle body side communication means for receiving a detection result of the state quantity detection means and a detection result of the noise detection means, which are provided in a vehicle body and wirelessly transmitted from the wheel side communication means, and the wheel specification means The wheel on which the state quantity detection unit corresponding to the noise detection unit is provided may be specified based on the detection result of the noise detection unit received by the vehicle body side communication unit.

  Generally, when wirelessly transmitting a detection result of a predetermined state quantity between the wheel side communication means and the vehicle body side communication means, it is difficult to specify the wheel provided with the state quantity detection means. According to the state monitoring system, it is possible to accurately identify the wheel provided with the state amount detection means.

  The noise detecting means detects noise a plurality of times during a predetermined time, and the wheel specifying means is based on a cumulative value of noise detected by the noise detecting means a plurality of times during a predetermined time. A wheel provided with the state quantity detection means corresponding to the above may be specified.

  In this case, since the wheel provided with the state quantity detection means is specified based on the accumulated value of the noise component detected a plurality of times during the predetermined time, the noise is not constantly generated. Can be handled with high accuracy. It is also possible to suppress the influence of environmental noise that can be brought about suddenly.

Vehicle acceleration / deceleration detecting means for detecting acceleration / deceleration of the vehicle including the wheels,
The wheel specifying means is based on the change state of noise derived from the detection result of the noise detection means and the change state of acceleration / deceleration of the vehicle derived from the detection result of the vehicle acceleration / deceleration detection means. You may make it identify the wheel in which the quantity detection means is provided.

  According to the wheel state monitoring system, it is possible to identify the wheel on which the state amount detection unit is provided by comparing the noise change state and the vehicle acceleration / deceleration change state. Based on the positional relationship between the noise generation source and each wheel, whether the wheel provided with the state quantity detection means is a front wheel or a rear wheel, or a drive wheel or a driven wheel. It may also be possible to identify.

  The wheel specifying unit is based on a detection result of the noise detection position specifying unit and a noise detection position specifying unit for specifying a positional relationship between the noise detection unit and a noise generation source based on a detection result of the noise detection unit. And a wheel position specifying unit for specifying the position of the wheel on which the state quantity detecting means corresponding to the noise detecting means is installed.

  In this case, the position of the wheel is specified after clarifying the positional relationship between the noise generation source and the wheel.

  The noise detecting means detects noise caused by the engine, and the wheel specifying means is provided with the state quantity detecting means corresponding to the noise detecting means based on the detection result of the noise detecting means. You may have a driving wheel determination part which determines whether a wheel is a front wheel or a rear wheel.

  In this case, it is possible to determine whether the wheel provided with the state quantity detection means is the front wheel or the rear wheel from the noise component that can change according to the positional relationship between the engine and the wheel.

  The noise detecting means detects noise caused by a motor that drives the wheel, and the wheel specifying means is configured so that the state quantity detecting means corresponding to the noise detecting means is based on a detection result of the noise detecting means. You may have the drive wheel determination part which determines whether the said wheel provided is a front wheel or a rear wheel.

  In this case, it is possible to determine whether the wheel provided with the state quantity detection means is a front wheel or a rear wheel from a noise component that can change according to the positional relationship between the motor and the wheel.

  The noise detecting means detects noise caused by wheel driving means provided corresponding to the wheel and driving the corresponding wheel, and the wheel specifying means acquires a driving state of the wheel driving means. Based on the driving state acquisition unit, the driving state of the wheel driving unit acquired by the driving state acquisition unit, and the detection result of the noise detection unit, the state amount detection unit corresponding to the noise detection unit is provided. A wheel identification unit that identifies the wheel that is present.

  In this case, it is possible to identify the wheel provided with the state quantity detection means from the noise component that can change according to the driving state of the wheel drive means. The wheel driving means includes, for example, an in-wheel motor mounted on each wheel and devices such as an inverter provided for driving the in-wheel motor.

  In addition, what combined each element mentioned above suitably, what was rearranged, and what represented this invention in different expression forms, such as a method, can also be contained in the range of the invention which requires protection by a patent by this patent application.

  According to the present invention, the wheel provided with the state quantity detection unit can be accurately identified from the detection result of the noise detection unit provided so as to correspond to the state quantity detection unit.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram illustrating an overall configuration of a vehicle 10 including a wheel state monitoring system according to the present embodiment.

  The vehicle 10 includes a vehicle body 12, a left rear wheel 20 a provided at the left rear of the vehicle body 12, a right rear wheel 20 b provided at the right rear of the vehicle body 12, a left front wheel 20 c provided at the left front of the vehicle body 12, and a right front of the vehicle body 12. And a spare front wheel 20e loaded on the rear part of the vehicle body 12. Hereinafter, the left rear wheel 20a, the right rear wheel 20b, the left front wheel 20c, the right front wheel 20d, and the spare wheel 20e are collectively referred to as “wheel 20”. Further, the left rear wheel 20a and the right rear wheel 20b are collectively referred to as “rear wheel”, and the left front wheel 20c and the right front wheel 20d are collectively referred to as “front wheel”. Further, the left rear wheel 20a and the left front wheel 20c are collectively referred to as “left wheel”, and the right rear wheel 20b and the right front wheel 20d are collectively referred to as “right wheel”.

  Each wheel 20 has a wheel acceleration / deceleration sensor 30, a noise detection device 32 provided so as to correspond to the wheel acceleration / deceleration sensor 30, and a transmitter 40 connected to the wheel acceleration / deceleration sensor 30 and the noise detection device 32. And a transmission antenna 50 connected to the transmitter 40.

  The wheel acceleration / deceleration sensor 30 is a sensor that detects the rotation acceleration / deceleration of the mounted wheel 20. The wheel acceleration / deceleration sensor 30 detects the rotation acceleration / deceleration of the wheel 20 every predetermined time and sends each detection result to the transmitter 40.

  The noise detection device 32 functions as noise detection means for detecting the noise level N of noise, and in the present embodiment, the noise detection device 32 mainly targets noise caused by the engine. The noise detection device 32 detects noise level N by extracting noise generated in the engine using a bandpass filter or the like, and can be realized by an analog circuit having a relatively simple configuration. Further, the noise detection device 32 of the present embodiment detects the noise level N of the noise a plurality of times during a predetermined time, obtains a cumulative value ΣN of the detected noise level N, and sends the cumulative value ΣN to the transmitter 40. send.

  The transmitter 40 transmits the detection results transmitted from each of the wheel acceleration / deceleration sensor 30 and the noise detection device 32 by radio waves via the transmission antenna 50. As the wheel acceleration / deceleration sensor 30, the transmitter 40, and the transmission antenna 50, those used in a TPMS (tire pressure monitoring system) that can individually monitor the state of each wheel 20 can be preferably used. It is.

  The vehicle body 12 is provided with an engine 58, an ECU 60, a receiver 42 and a vehicle acceleration / deceleration sensor 59 connected to the ECU 60, and a receiving antenna 52 connected to the receiver 42.

  The engine 58 is a front engine disposed in the front portion of the vehicle body 12 and includes an ignition system. Further, the engine 58 of the present embodiment is a noise generation source, and generates particularly large noise when the ignition system is operated. Noise generated in the engine 58 is detected by a noise detection device 32 provided in each wheel 20. In the present embodiment, the front wheels are driven wheels that are driven by the output from the engine 58. Therefore, the vehicle 10 of the present embodiment employs a so-called FF system having a front engine / front drive arrangement.

  The vehicle acceleration / deceleration sensor 59 is a sensor that detects an acceleration / deceleration related to traveling of the vehicle 10, and sends a detection result to the ECU 60. The vehicle acceleration / deceleration sensor 59 is configured by a sensor that can directly or indirectly detect the acceleration / deceleration of the vehicle 10. Accordingly, for example, the vehicle acceleration / deceleration sensor 59 can be configured by indirectly deriving the acceleration / deceleration of the vehicle 10 from the detection value of the wheel speed sensor that detects the rotation speed of the wheel 20.

  The receiver 42 receives data transmitted by radio waves from the transmitter 40 and the transmission antenna 50 provided on each wheel 20 via the reception antenna 52 and sends the data to the ECU 60. The receiver 42 of the present embodiment receives the detection result of the wheel acceleration / deceleration sensor 30 and the detection result of the noise detection device 32 that are sent via each transmitter 40 and each transmission antenna 50.

  Based on various data sent from the receiver 42, the ECU 60 specifies which wheel 20 the data included in the signal received by the receiver 42 relates to, and the rotational acceleration / deceleration of each wheel 20. The state quantity such as is monitored.

  FIG. 2 is a functional block diagram of the ECU 60, and is a diagram showing a portion involved in monitoring the state of the wheel 20 in the present embodiment. The ECU 60 includes a noise detection position specifying unit 62, a wheel position specifying unit 64, a drive wheel determining unit 66, a monitoring unit 68, and a storage unit 70.

  The noise detection position specifying unit 62 specifies the positional relationship between the noise detection device 32 and the engine 58 that is a noise generation source from the cumulative value ΣN of the noise level N that is the detection result of the noise detection device 32. Specifically, when the accumulated value ΣN of the noise level N is relatively large, the noise detection device 32 and the engine 58 are disposed close to each other, and when the accumulated value ΣN of the noise level N is relatively small, The noise detection position specifying unit 62 determines that the noise detection device 32 and the engine 58 are spaced apart.

  The wheel position specifying unit 64 specifies the position of the wheel 20 on which the wheel acceleration / deceleration sensor 30 corresponding to the noise detection device 32 is installed based on the detection result of the noise detection position specifying unit 62. Thereby, it can be judged which wheel 20 the data regarding the acceleration / deceleration of the wheel 20 received by the receiver 42 relates to. Specifically, the wheel position specifying unit 64 determines that the wheel 20 provided with the wheel acceleration / deceleration sensor 30 is the right wheel based on the detection result of the wheel acceleration / deceleration sensor 30 and the detection result of the vehicle acceleration / deceleration sensor 59. The left wheel or the spare wheel 20e is determined.

  FIG. 3 is a diagram showing a wheel acceleration / deceleration sensor 30 arranged on each wheel 20. The wheel acceleration / deceleration sensor 30 of the present embodiment detects the acceleration in the arrow G + direction in FIG. 3 as a positive component and detects the acceleration in the arrow G− direction in FIG. 3 as a negative component. When the vehicle 10 including the wheels 20 is accelerated / decelerated, the detected component of the wheel acceleration / deceleration sensor 30 for the left wheel attached to the left side of the vehicle 10 and the wheel acceleration / deceleration of the right wheel attached to the right side of the vehicle 10 are detected. The detection component of the sensor 30 is opposite in sign. Based on this fact, the wheel position specifying unit 64 compares the detection result of the wheel acceleration / deceleration sensor 30 with the detection result of the vehicle acceleration / deceleration sensor 59, so that the wheel 20 provided with the wheel acceleration / deceleration sensor 30 is detected. Specify whether it is the right wheel or the left wheel. Further, the spare wheel 20e loaded on the vehicle body 12 has a rotational acceleration / deceleration rate of almost zero regardless of the acceleration / deceleration of the vehicle 10. Therefore, the wheel position specifying unit 64 determines that the wheel 20 provided with the wheel acceleration / deceleration sensor 30 is the spare wheel 20e when the detection value of the wheel acceleration / deceleration sensor 30 is always almost zero. .

  The wheel position specifying unit 64 shown in FIG. 2 specifies the position of the wheel 20 from the position information of the engine 58 stored in advance in the storage unit 70 and the specifying result of the noise detection position specifying unit 62, and the wheel 20 Is the front wheel or the rear wheel. In the present embodiment, since the engine 58 is mounted on the front portion of the vehicle body 12, the front wheels are arranged closer to the engine 58 than the rear wheels. Accordingly, when the noise detection position specifying unit 62 determines that the noise detection device 32 and the engine 58 are arranged close to each other, the wheel acceleration / deceleration sensor 30 corresponding to the noise detection device 32 is mounted on the front wheel. Can be determined. On the other hand, when the noise detection position specifying unit 62 determines that the noise detection device 32 and the engine 58 are spaced apart from each other, the wheel acceleration / deceleration sensor 30 corresponding to the noise detection device 32 is attached to the rear wheel. It can be determined that it is installed.

  As described above, the wheel position specifying unit 64 includes the left rear wheel 20a, the right rear wheel 20b, the left front wheel 20c, and the right front wheel, on which the wheel acceleration / deceleration sensor 30 corresponding to the noise detection device 32 is installed. 20d or the spare wheel 20e is specified.

  The driving wheel determination unit 66 is provided with a wheel acceleration / deceleration sensor 30 corresponding to the noise detection device 32 based on the position of the wheel 20 obtained by the wheel position specification unit 64 based on the detection result of the noise detection device 32. It is determined whether or not the wheel 20 is a driving wheel. In the present embodiment, the drive wheel determination unit 66 is based on the driving method of the vehicle 10 stored in advance in the storage unit 70 and the position of the wheel 20 specified by the wheel position specifying unit 64. It is determined whether or not is a driving wheel. For example, when the driving method of the vehicle 10 is front wheel driving and the wheel position specifying unit 64 specifies that the wheel 20 is the left front wheel 20c or the right front wheel 20d, the wheel 20 is a driving wheel. Determined. On the other hand, when the wheel position specifying unit 64 specifies that the wheel 20 is the left rear wheel 20a or the right rear wheel 20b, it is determined that the wheel 20 is not a driving wheel.

  The storage unit 70 stores various data of the vehicle 10 such as position information of the engine 58 and a driving method of the vehicle 10. The storage unit 70 can also appropriately store various data sent from the receiver 42, the vehicle acceleration / deceleration sensor 59, or each unit of the ECU 60. Each unit of the ECU 60 can appropriately read various data stored in the storage unit 70.

  The monitoring unit 68 receives the detection result of the wheel acceleration / deceleration sensor 30 sent from the receiver 42, the detection result of the noise detection device 32, the detection result of the vehicle acceleration / deceleration sensor 59, the identification result in the wheel position identification unit 64, and the driving wheel. The state of the wheel 20 is monitored based on the determination result in the determination unit 66 and the like. For example, the monitoring unit 68 associates the detection result of the wheel acceleration / deceleration sensor 30 sent from the receiver 42 with the position of the wheel 20 specified by the wheel position specifying unit 64 to rotate the wheel 20. Monitor acceleration / deceleration status. Note that the monitoring data in the monitoring unit 68 can be stored in the storage unit 70 as appropriate.

  In the ECU 60 having the above-described configuration, the wheel specifying means for specifying the wheel 20 provided with the wheel acceleration / deceleration sensor 30 based on the detection result of the noise detection device 32 includes a noise detection position specifying unit 62, a wheel position specifying. The unit 64, the drive wheel determination unit 66, and the storage unit 70 are configured.

  Next, the operation of this embodiment will be described.

  FIG. 4 is a flowchart regarding the specification of the wheel 20 in the wheel state monitoring system. In order to identify which wheel 20 the data included in the radio wave received by the receiver 42 relates to, the wheel state monitoring system firstly sets the wheel 20 to the right wheel, the left wheel, or the spare wheel 20e. Is determined (S11 in FIG. 4). Specifically, in the wheel position specifying unit 64 of the ECU 60, the acceleration / deceleration state of the vehicle 10 detected by the vehicle acceleration / deceleration sensor 59 and the detected component of the wheel acceleration / deceleration sensor 30 received by the receiver 42 are positive / negative. Accordingly, it is specified whether the wheel 20 is a left wheel, a right wheel, or a spare wheel 20e (see FIG. 3).

  When the wheel position specifying unit 64 determines that the wheel 20 is the spare wheel 20e (YES in S12), the position of the wheel 20 has already been specified, so that each step of S13 and S14 described later is performed. Is skipped. On the other hand, when it is specified that the wheel 20 is not the spare wheel 20e but the left wheel or the right wheel (NO in S12), it is specified whether the wheel 20 is a front wheel or a rear wheel (S13). . Specifically, it is specified as shown in FIG.

FIG. 5 is a flowchart regarding the specification of a front wheel or a rear wheel. First, in the noise detection device 32, a noise acquisition timer T that determines the degree of accumulation in determining the accumulated value ΣN of the noise level N is initialized and set to T = T ₀ (S21 in FIG. 5). T ₀ affects the number of times of noise detection by the noise detection device 32, and any natural number can be adopted. Then, the noise detection device 32 detects the noise level N of the noise (S22), and sets T = T−1 to make the noise acquisition timer T minus 1 as a new noise acquisition timer T. (S23).

  Then, the noise detection device 32 determines whether or not T = 0 has been reached (S24). When it is determined that T = 0 has not been reached (NO in S24), the noise detection device 32 repeats S22 and S23 described above, and detects the noise level N of noise according to the noise acquisition timer T. When it is determined that T = 0 has been reached (YES in S24), the noise detection device 32 calculates a cumulative value ΣN of the detected noise level N (S25). Then, the calculated cumulative value ΣN of the noise level N is sent from the noise detection device 32 to the transmitter 40, and together with the detection result of the corresponding wheel acceleration / deceleration sensor 30, the transmission antenna 50, the reception antenna 52, and the receiver 42 are used. To the ECU 60.

  In the ECU 60, based on the cumulative value ΣN of the noise level N sent from the receiver 42, the positional relationship between the noise detection device 32 that detects the cumulative value ΣN and the engine 58 is determined by the noise detection position specifying unit 62. It is specified (S26). Specifically, the noise detection position specifying unit 62 specifies the distance between the noise detection device 32 and the engine 58 from the magnitude of the cumulative value ΣN of the noise level N. And the position of the wheel 20 in which the noise detection apparatus 32 and the wheel acceleration / deceleration sensor 30 are provided is specified in the wheel position specific | specification part 64 (S27). Specifically, the wheel position specifying unit 64 acquires the arrangement of the engine 58 stored in the storage unit 70 and the positional relationship between the noise detection device 32 and the engine 58 specified by the noise detection position specifying unit 62. Thus, it is specified whether the wheel 20 is a front wheel or a rear wheel.

  By specifying “whether the wheel 20 is the right wheel or the left wheel” and “whether the wheel 20 is the front wheel or the rear wheel” as described above, the wheel 20 is the left rear wheel 20a, the right wheel Any one of the rear wheel 20b, the left front wheel 20c, and the right front wheel 20d is specified.

  Thereafter, the drive wheel determination unit 66 determines whether or not the target wheel 20 is a drive wheel (S14 in FIG. 4). Specifically, the driving wheel determination unit 66 acquires the driving method of the vehicle 10 stored in advance in the storage unit 70 and the position of the wheel 20 specified by the wheel position specifying unit 64, so that the wheel 20 It is determined whether it is a driving wheel.

  In this way, it is specified whether the wheel 20 is a front wheel or a rear wheel or a driving wheel. The monitoring unit 68 of the ECU 60 appropriately monitors the state of the wheel 20.

  As described above, according to the wheel state monitoring system of the present embodiment, the wheel 20 can be specified with high accuracy, and the data such as the detection result of the wheel acceleration / deceleration sensor 30 sent from the transmitter 40 will be It is possible to accurately determine whether the wheel 20 is related to the wheel 20. In particular, since the position of the wheel 20 is specified based on the difference in the noise level N transmitted from the engine 58, the position of the wheel 20 can be determined even if only one set of the receiver 42 and the receiving antenna 52 is provided. It can be specified with high accuracy. In the present embodiment, only one set of receiving means including the receiver 42 and the receiving antenna 52 is provided, so that the wheel state monitoring is performed as compared with the case where a plurality of sets of the receiver 42 and the receiving antenna 52 are provided. The system can be realized at a low cost, and can be favorably applied to a system such as TPMS.

  Further, by specifying the wheel 20 based on the cumulative value ΣN of the noise level N, it is possible to specify the position of the wheel 20 with high accuracy even when the generation of noise from the engine 58 is random. .

  In addition, since the engine 58 that is a noise generation source is often mounted on the front or rear portion of the vehicle 10, according to the present embodiment as described above, the target wheel 20 is disposed forward. It is possible to determine relatively easily whether it is arranged or arranged rearward.

  Next, each modification of the present embodiment will be described.

  In the above-described embodiment, the engine 58 is a noise generation source, and the noise detection device 32 provided in each wheel 20 detects the noise generated in the engine 58, but other devices are regarded as noise. It is also possible to use as a detection target. For example, in the case of an electric vehicle in which the wheel 20 is driven by a wheel drive motor provided in the vehicle body 12, noise caused by the wheel drive motor can be detected by each noise detection device 32. Also in this case, the noise detection position specifying unit 62, the wheel position specifying unit 64, the drive wheel determining unit 66, the monitoring unit 68, and the storage unit 70 of the ECU 60 function in the same manner as in the above-described embodiment. Based on the data sent from the receiver 42, the ECU 60 specifies which wheel the data included in the radio wave received by the receiver 42 relates to, and monitors the state of the wheel 20.

  Further, when there is originally a clear difference between the noise detection devices 32 regarding the magnitude of the detected noise level N, the wheel 20 is specified based on the detected value of the noise level N. Is possible. For example, when the order related to the magnitude of the noise level N detected by the noise detection device 32 can be associated with the position of the wheel 20 on which the noise detection device 32 is provided, the detection of the noise detection device 32 is performed. Based on the result, it is possible to identify the wheel 20 provided with the state quantity detection means corresponding to the noise detection means.

(Second Embodiment)
In the present embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 6 is a diagram showing an overall configuration of the vehicle 10 of the present embodiment.

  In the present embodiment, instead of the engine 58, a so-called in-wheel motor 80 mounted on each wheel 20 serves as a drive source, and the wheel 20 is rotationally driven. The vehicle body 12 is equipped with a motor control unit 82 provided so as to correspond to each in-wheel motor 80, and each motor control unit 82 is controlled by the ECU 60.

  The in-wheel motor 80 rotationally drives the mounted wheel 20 according to the amount of current supplied from the motor control unit 82. Therefore, each wheel 20 can be driven to rotate independently.

  The motor control unit 82 is configured to include a power converter such as an inverter, and converts the discharge power from a battery (not shown) into an appropriate power format and supplies it to the in-wheel motor 80. The motor control unit 82 adjusts the amount of current supplied to the in-wheel motor 80 in accordance with the torque command from the ECU 60, and causes the corresponding in-wheel motor 80 to output a torque corresponding to the torque command. ing.

  FIG. 7 is a functional block diagram of the ECU 60 according to the present embodiment, and is a diagram showing a part involved in monitoring the state of the wheel 20 in the present embodiment. The ECU 60 includes a drive control unit 72, a drive state acquisition unit 74, a wheel identification unit 76, a drive wheel determination unit 66, a monitoring unit 68, and a storage unit 70.

  The drive control unit 72 controls each motor control unit 82 in accordance with an acceleration / deceleration instruction from the driver of the vehicle 10 and controls the drive torque and the like of each in-wheel motor 80. Data relating to the drive state such as the drive torque of each in-wheel motor 80 controlled by the drive control unit 72 is stored in the storage unit 70.

  The drive state acquisition unit 74 acquires data relating to the drive state such as the drive torque of each in-wheel motor 80 stored in the storage unit 70.

  The wheel specifying unit 76 is provided with the wheel acceleration / deceleration sensor 30 corresponding to the noise detecting device 32 based on the driving state of each in-wheel motor 80 acquired by the driving state acquiring unit 74 and the detection result of the noise detecting device 32. The wheel 20 is identified. For example, the noise detection device 32 mounted on the same wheel 20 as the in-wheel motor 80 in the driving state detects a large noise level N, and the accumulated value ΣN also increases. Further, when the driving state of the in-wheel motor 80 changes, the noise level N detected by the noise detection device 32 also changes, and the cumulative value ΣN also changes. Based on the relationship between the driving state of the in-wheel motor 80 and the detection result of the noise detection device 32, the wheel specifying unit 76 is provided with the wheel acceleration / deceleration sensor 30 corresponding to the noise detection device 32. The wheel 20 is specified.

  The monitoring unit 68 receives the detection result of the wheel acceleration / deceleration sensor 30 sent from the receiver 42, the detection result of the noise detection device 32, the detection result of the vehicle acceleration / deceleration sensor 59, the acquisition result in the driving state acquisition unit 74, and the wheel identification. The state of the wheel 20 is monitored based on the identification result in the unit 76, the determination result in the drive wheel determination unit 66, and the like.

  The storage unit 70 stores various data of the vehicle 10 such as data related to a driving state such as a torque amount of each in-wheel motor 80 by the drive control unit 72. The storage unit 70 can also appropriately store various data sent from the receiver 42, the vehicle acceleration / deceleration sensor 59, or each unit of the ECU 60. Each unit of the ECU 60 can appropriately read various data stored in the storage unit 70.

  The noise detection device 32 according to the present embodiment mainly detects noise caused by the corresponding in-wheel motor 80 and / or the motor control unit 82.

  Other configurations are substantially the same as those of the first embodiment shown in FIGS.

  The wheel state monitoring system according to the present embodiment is also the first embodiment shown in FIG. 4 described above in order to specify which wheel 20 the data included in the radio wave received by the receiver 42 relates to. In the same manner as in FIG. 4, it is specified whether the wheel 20 is a left wheel, a right wheel, or a spare wheel 20e (S11 in FIG. 4). When it is determined that the wheel 20 is the spare wheel 20e (YES in S12), S13 and S14 shown in FIG. 4 are skipped, and the wheel 20 is specified as the left wheel or the right wheel. (NO in S12), it is specified whether the wheel 20 is a front wheel or a rear wheel (S13). Specifically, as shown in FIG. 8, it is specified whether the wheel 20 is a front wheel or a rear wheel.

FIG. 8 is a flowchart relating to the specification of the front wheel or the rear wheel in the present embodiment. First, the noise detector 32, (S31 in FIG. 8) noise acquisition timer T is set is initialized to T = _{T 0,} the noise the noise level N is detected in the (S32), noise acquisition timer T, T = T-1 (S33). Then, whether or not T = 0 has been reached is determined in the noise detection device 32 (S34), and if it is determined that T = 0 has not been reached (NO in S34), the noise detection device 32 is described above. S32 and S33 are repeated, and the noise level N of the noise is detected according to the noise acquisition timer T. When it is determined that T = 0 has been reached (YES in S34), the noise detection device 32 calculates a cumulative value ΣN of the detected noise level N (S35). The calculated cumulative value ΣN of the noise level N is sent from the noise detection device 32 to the transmitter 40, and together with the detection result of the corresponding wheel acceleration / deceleration sensor 30, the transmission antenna 50, the reception antenna 52, and the receiver 42 are used. It is sent to the ECU 60.

  In the ECU 60, the driving state of each in-wheel motor 80 stored in the storage unit 70 is acquired by the driving state acquisition unit 74 (S36). Then, the driving state of each in-wheel motor 80 acquired by the driving state acquisition unit 74 is compared with the cumulative value ΣN of the noise level N that is the detection result of the noise detection device 32, and corresponds to the noise detection device 32. The wheel 20 provided with the wheel acceleration / deceleration sensor 30 is specified by the wheel specifying unit 76 (S37).

  By specifying the position of the wheel 20 as described above, for example, the driving states of the in-wheel motor 80 of the left rear wheel 20a and the in-wheel motor 80 of the right rear wheel 20b are equal, and the in-wheel of the left front wheel 20c is the same. Even when the driving states of the in-wheel motor 80 of the motor 80 and the right front wheel 20d are substantially equal, the wheel specifying unit 76 has the wheels 20 as the left rear wheel 20a, the right rear wheel 20b, the left front wheel 20c, It is possible to accurately identify the right front wheel 20d or the spare wheel 20e.

  And if the position of the wheel 20 is specified, it will be determined in the drive wheel determination part 66 whether the wheel 20 in which the wheel acceleration / deceleration sensor 30 corresponding to the noise detection apparatus 32 is provided is a drive wheel (FIG. 4 S14). In this way, it is specified whether the wheel 20 is a front wheel or a rear wheel or a driving wheel. The monitoring unit 68 of the ECU 60 appropriately monitors the state of the wheel 20.

  As described above, also in the vehicle 10 that employs the in-wheel motor 80, the wheel state monitoring system according to the present invention can accurately identify the position of the wheel 20 and the wheel sent from the transmitter 40. It is possible to accurately determine to which wheel 20 the data such as the detection result of the acceleration / deceleration sensor 30 relates.

  When the driving state of each wheel 20 included in the vehicle 10 is different, the right wheel, the left wheel, or the spare wheel 20e based on the detected value of the wheel acceleration / deceleration sensor 30 in the wheel specifying unit 76 of the ECU 60. It is also possible to omit processing related to the determination. In this case, the wheel identification unit 76 corresponds to the noise detection device 32 by comparing the drive state of each in-wheel motor 80 acquired by the drive state acquisition unit 74 with the detection result of the noise detection device 32. It is possible to specify the position of the wheel 20 provided with the wheel acceleration / deceleration sensor 30 (see S31 to S37 in FIG. 8).

  The present invention is not limited to the above-described embodiments, and various modifications such as design changes can be added based on the knowledge of those skilled in the art. The form can also be included in the scope of the present invention.

  For example, in the above description, the vehicle 10 using either the engine 58 or the motor as a drive source for the wheels 20 has been described. However, the same applies to a so-called hybrid vehicle that employs both the engine 58 and the motor. The present invention can be applied.

  Further, the cumulative value ΣN of the noise level N detected by each noise detection device 32 can be calculated in equipment such as the ECU 60 provided on the vehicle body 12 side.

  Further, regarding the noise level N used when specifying the wheel 20, the detection value per one time of each noise detection device 32 can be used instead of the cumulative value ΣN of the detection value of each noise detection device 32. is there.

  It is also possible to set the various processes relating to the specification of the wheel position as described above to be automatically performed at the time of wheel replacement, and to let the ECU learn the wheel position. At this time, when each wheel is rotationally driven by an in-wheel motor, for example, as in the second embodiment, each in-wheel motor is intentionally changed so that the driving state between the in-wheel motors is different. It is also possible to control a wheeled motor.

  Further, it is possible to identify the wheel 20 provided with the wheel acceleration / deceleration sensor 30 based on the change state of the noise and the change state of the acceleration / deceleration of the vehicle 10. For example, the ECU 60 compares the vehicle acceleration / deceleration change state derived from the detection result of the vehicle acceleration / deceleration sensor 59 with the noise change state derived from the detection result of the noise detection device 32 to thereby detect the wheel acceleration / deceleration sensor. The wheel 20 provided with 30 can be specified. When the FF engine is a noise generation source, the operating state of the engine becomes active during vehicle acceleration, and the noise generated by the engine also increases. Therefore, the detected value of the noise detection device 32 provided on the front wheel is large during vehicle acceleration. In this way, by comparing the noise change state and the vehicle acceleration / deceleration change state, the influence of the noise component that can be brought about by the external environment is suppressed, and the wheel provided with the wheel acceleration / deceleration sensor 30 becomes the front wheel and It is possible to accurately identify the rear wheel. When the in-wheel motor is a noise generation source, the detection value of the noise detection device 32 mounted on the same wheel as the actually operating motor is large. Therefore, by comparing the change state of the noise and the change state of the vehicle acceleration / deceleration, whether the wheel provided with the wheel acceleration / deceleration sensor 30 is located at which position, or whether it is a driving wheel. Can be specified with high accuracy.

It is a figure showing the whole vehicle composition of a 1st embodiment. It is a functional block diagram of ECU of 1st Embodiment. It is a figure which shows the acceleration / deceleration sensor arrange | positioned at the wheel. It is a flowchart regarding specification of the wheel in a wheel state monitoring system. It is a flowchart regarding specification of the front wheel or the rear wheel in the first embodiment. It is a figure which shows the whole structure of the vehicle of 2nd Embodiment. It is a functional block diagram of ECU of 2nd Embodiment. It is a flowchart regarding specification of the wheel in 2nd Embodiment.

Explanation of symbols

10 vehicle, 12 vehicle body, 20 wheel, 30 wheel acceleration / deceleration sensor, 32 noise detection device, 40 transmitter, 42 receiver, 50 transmission antenna, 52 reception antenna, 60 ECU, 62 noise detection position specifying unit, 64 wheel position specifying Unit, 66 drive wheel determination unit, 68 monitoring unit, 70 storage unit, 72 drive control unit, 74 drive state acquisition unit, 76 wheel identification unit, 80 in-wheel motor, 82 motor control unit

Claims (8)

A wheel condition monitoring system for monitoring a wheel condition,
State quantity detection means provided on the wheel for detecting a predetermined state quantity;
Noise detection means provided to correspond to the state quantity detection means and detecting noise emitted from a noise generation source;
Based on the detection result of the noise detection means, wheel specifying means for specifying the wheel provided with the state quantity detection means corresponding to the noise detection means;
A wheel condition monitoring system comprising: Wheel-side communication means that wirelessly transmits a detection result of the state quantity detection means and a detection result of the noise detection means provided to correspond to the state quantity detection means provided on the wheel;
A vehicle body side communication unit that is provided on a vehicle body to which the wheel is attached and receives the detection result of the state quantity detection unit and the detection result of the noise detection unit that are wirelessly transmitted from the wheel side communication unit;
The wheel specifying means specifies the wheel provided with the state quantity detection means corresponding to the noise detection means based on the detection result of the noise detection means received by the vehicle body side communication means. The wheel state monitoring system according to claim 1. The noise detection means detects noise a plurality of times during a predetermined time,
The wheel specifying means specifies a wheel provided with the state quantity detecting means corresponding to the noise detecting means based on a cumulative value of noise detected by the noise detecting means a plurality of times during a predetermined time. The wheel state monitoring system according to claim 1 or 2. Vehicle acceleration / deceleration detecting means for detecting acceleration / deceleration of the vehicle including the wheels,
The wheel specifying means is based on the noise change state derived from the detection result of the noise detection means and the vehicle acceleration / deceleration change state derived from the detection result of the vehicle acceleration / deceleration detection means. The wheel state monitoring system according to any one of claims 1 to 3, wherein a wheel provided with a quantity detection means is specified. The wheel specifying means includes
Based on the detection result of the noise detection unit, a noise detection position specifying unit that specifies a positional relationship between the noise detection unit and a noise generation source;
Based on the detection result of the noise detection position specifying unit, a wheel position specifying unit for specifying the position of the wheel on which the state quantity detection unit corresponding to the noise detection unit is installed;
The wheel state monitoring system according to any one of claims 1 to 4, further comprising: The noise detecting means detects noise caused by the engine;
The wheel identifying means determines, based on the detection result of the noise detecting means, whether the wheel provided with the state quantity detecting means corresponding to the noise detecting means is a front wheel or a rear wheel. The wheel state monitoring system according to claim 1, further comprising a determination unit. The noise detecting means detects noise caused by a motor driving the wheel;
The wheel identifying means determines, based on the detection result of the noise detecting means, whether the wheel provided with the state quantity detecting means corresponding to the noise detecting means is a front wheel or a rear wheel. The wheel state monitoring system according to claim 1, further comprising a determination unit. The noise detecting means detects noise caused by wheel driving means that is provided corresponding to the wheel and drives the corresponding wheel,
The wheel specifying means includes
A driving state acquisition unit for acquiring a driving state of the wheel driving means;
Based on the driving state of the wheel driving unit acquired by the driving state acquisition unit and the detection result of the noise detecting unit, the wheel on which the state amount detecting unit corresponding to the noise detecting unit is provided is specified. A wheel state monitoring system according to any one of claims 1 to 3, further comprising: a wheel specifying unit.

Images