WO2014141690A1 - タイヤ装置 - Google Patents
タイヤ装置 Download PDFInfo
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- WO2014141690A1 WO2014141690A1 PCT/JP2014/001362 JP2014001362W WO2014141690A1 WO 2014141690 A1 WO2014141690 A1 WO 2014141690A1 JP 2014001362 W JP2014001362 W JP 2014001362W WO 2014141690 A1 WO2014141690 A1 WO 2014141690A1
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- tire
- vibration
- power generation
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- 238000010248 power generation Methods 0.000 claims abstract description 56
- 238000012545 processing Methods 0.000 claims abstract description 49
- 230000008859 change Effects 0.000 claims abstract description 15
- 239000000758 substrate Substances 0.000 claims description 43
- 238000001514 detection method Methods 0.000 claims description 31
- 238000000605 extraction Methods 0.000 claims description 4
- 230000002123 temporal effect Effects 0.000 abstract description 3
- 230000006870 function Effects 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 238000012360 testing method Methods 0.000 description 6
- 230000001133 acceleration Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 230000035945 sensitivity Effects 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 230000006698 induction Effects 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 239000010426 asphalt Substances 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000005674 electromagnetic induction Effects 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
- B60C23/00—Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
- B60C23/06—Signalling devices actuated by deformation of the tyre, e.g. tyre mounted deformation sensors or indirect determination of tyre deformation based on wheel speed, wheel-centre to ground distance or inclination of wheel axle
- B60C23/065—Signalling devices actuated by deformation of the tyre, e.g. tyre mounted deformation sensors or indirect determination of tyre deformation based on wheel speed, wheel-centre to ground distance or inclination of wheel axle by monitoring vibrations in tyres or suspensions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
- B60C19/00—Tyre parts or constructions not otherwise provided for
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
- B60C23/00—Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
- B60C23/02—Signalling devices actuated by tyre pressure
- B60C23/04—Signalling devices actuated by tyre pressure mounted on the wheel or tyre
- B60C23/0408—Signalling devices actuated by tyre pressure mounted on the wheel or tyre transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver
- B60C23/041—Means for supplying power to the signal- transmitting means on the wheel
- B60C23/0411—Piezoelectric generators
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
- B60C23/00—Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
- B60C23/06—Signalling devices actuated by deformation of the tyre, e.g. tyre mounted deformation sensors or indirect determination of tyre deformation based on wheel speed, wheel-centre to ground distance or inclination of wheel axle
- B60C23/064—Signalling devices actuated by deformation of the tyre, e.g. tyre mounted deformation sensors or indirect determination of tyre deformation based on wheel speed, wheel-centre to ground distance or inclination of wheel axle comprising tyre mounted deformation sensors, e.g. to determine road contact area
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
- B60T8/17—Using electrical or electronic regulation means to control braking
- B60T8/172—Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters
- B60T8/1725—Using tyre sensors, e.g. Sidewall Torsion sensors [SWT]
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
- B60C19/00—Tyre parts or constructions not otherwise provided for
- B60C2019/004—Tyre sensors other than for detecting tyre pressure
Definitions
- the present disclosure relates to an apparatus for estimating the state of a tire from a detection value of a sensor attached to the tire.
- Patent Document 1 there is a tire device that estimates the state of a tire (for example, Patent Document 1).
- an acceleration sensor is provided on the tire tread (portion in contact with the ground surface of the tire) on the tire inner side, and vibration generated in the tread portion is detected from the output value of the acceleration sensor. Then, the friction coefficient between the tire and the road surface is estimated from the time change of the detected vibration level.
- a tire or a transmitter is provided inside the tire to process data detected by the sensor, To send data to. Therefore, electric power for driving these microcomputers and transmitters is required. Since it is difficult to supply power from a power supply outside the tire (for example, a car battery) to a transmitter inside the tire, a battery is provided inside the tire.
- the present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to provide a tire device that further downsizes a device attached to the inside of the tire.
- a tire device includes a vibration power generation element that is disposed inside a tire and outputs a voltage corresponding to a temporal change in vibration that occurs in a tread of the tire; the vibration power generation element that is disposed inside the tire; A signal processing unit that performs signal processing on the output voltage of the tire, and a transmitter that is disposed inside the tire and that transmits data processed by the signal processing unit to a device provided outside the tire, Prepare.
- the signal processing unit and the transmitter are driven by electric power generated by the vibration power generation element.
- the vibration power generation element generates power by vibration generated in the tread, and the signal processing unit and the transmitter inside the tire are driven by the power generated by the vibration power generation element. Therefore, the vibration power generation element has a role of outputting a signal corresponding to a time change of vibration and a role of supplying electric power for driving the signal processing unit inside the tire. For this reason, it is not necessary to separately provide a battery for driving the signal processing unit and the transmitter inside the tire. Therefore, the member attached inside the tire in the tire device can be reduced in size.
- the drawing It is a block diagram for explaining composition of a tire device concerning an embodiment of this indication. It is sectional drawing of a radial direction when a tire provided with the tire side apparatus concerning this embodiment is seen from a horizontal direction. It is a schematic diagram for demonstrating the structure of the vibration electric power generation element which concerns on this embodiment. It is a figure showing the time change of the voltage which a vibration electric power generation element outputs. It is a figure which shows the example of the other structure of a vibration electric power generation element. It is a figure which shows the example of the other structure of a vibration electric power generation element.
- FIG. 1 is a block diagram for explaining a configuration of a tire device 100 according to the present embodiment.
- the tire device 100 includes a tire-side device 1 and a vehicle-side device 2.
- the tire-side device 1 includes a vibration power generation element 11, a power supply circuit 12, a signal processing unit 14, and a transmitter 15.
- the vehicle side device 2 includes a receiving unit 21, a wheel speed detecting unit 22, a signal processing unit 23, and a loaded weight detecting unit 24.
- the outline of the operation of the tire device 100 in the present embodiment is as follows.
- the tire side device 1 provided inside the tire 6 detects vibration generated in the tread 60 of the tire 6, and transmits various data obtained from temporal changes in the amplitude of the vibration to the vehicle side device 2.
- the vehicle side device 2 calculates the friction coefficient between the road surface 7 and the tire 6 and the air pressure of the tire 6 from the data acquired from the tire side device 1 and data such as the wheel speed.
- the calculated data such as the coefficient of friction between the road surface 7 and the tire 6 and the air pressure of the tire 6 are used for control processing by various control systems such as ABS (Antilocked Braking System).
- ABS Antilocked Braking System
- the tire-side device 1 is disposed in the vicinity of the center in the tire width direction (hereinafter referred to as the tire width direction) on the tread back surface of the tire 6 included in the own vehicle (the surface contacting the road surface 7 is the surface).
- the vibration power generation element 11 included in the tire side device 1 converts vibration energy into electric energy, and a direction in contact with a circular orbit drawn by the tire side device 1 when the tire 6 rotates (tire tangent direction: in FIG. 2).
- Tire tangent direction: in FIG. 2). Are arranged so as to generate electric power against vibration in the direction of arrow X).
- FIG. 3 shows a radial cross-sectional view of the tire 6 for explaining the configuration of the vibration power generation element 11 as viewed from the lateral direction.
- the vibration power generation element 11 is an electrostatic induction type power generation element, but may be a piezoelectric element, a frictional type, a magnetostrictive type, or an electromagnetic induction type element.
- the vibration power generation element 11 includes an electret electrode E, an electret electrode substrate 11E, a counter electrode P, and a counter electrode substrate 11P.
- the electret electrode E holds a constant charge semipermanently, and here holds a negative charge.
- a plurality of strip-shaped electret electrodes E are extended in the tire width direction on the surface of the electret electrode substrate 11E, and each electret electrode E is arranged in parallel to the tire tangential direction.
- a plurality of strip-like counter electrodes P are extended in the tire width direction and arranged in parallel to the tire tangential direction on the surface of the counter electrode substrate 11P.
- the counter electrode P and the electret electrode E have the same width in the tire tangent direction. Of course, the width of these electrodes may be appropriately designed.
- the electret electrode substrate 11E and the counter electrode substrate 11P are arranged so that the electret electrode E and the counter electrode P provided in each of the electret electrode substrate 11E and the counter electrode substrate 11P are opposed to each other. Further, the electret electrode substrate 11E is fixed so as not to move with respect to the housing of the tire side device 1.
- the counter electrode substrate 11 ⁇ / b> P is attached to the housing of the tire side device 1 by springs K ⁇ b> 1 having a predetermined spring constant at both ends in the tire tangential direction. Therefore, the counter electrode substrate 11P moves mainly parallel to the tire tangential direction.
- the spring constant of the spring K1 is set so that the counter electrode substrate 11P vibrates with high sensitivity to vibration with a frequency of 10 Hz to 10 kHz generated in the tread 60.
- Terminals A and B are connected to a power supply circuit 12 and a signal processing unit 14, which will be described later.
- the power supply circuit 12 is a circuit for supplying the power generated by the vibration power generation element 11 to the signal processing unit 14 and the transmitter 15, and includes a rectification unit 121 and a power storage unit 122.
- the rectifier 121 is a known rectifier circuit for converting AC power output from the vibration power generation element 11 into DC power.
- the AC power generated by the vibration power generation element 11 is converted into DC power by the rectifying unit 121 and output to the power storage unit 122.
- the rectifier 121 may be a full-wave rectifier circuit or a half-wave rectifier circuit.
- the power storage unit 122 is a circuit for storing the DC power input from the rectifying unit 121, and is mainly composed of a capacitor.
- the electric power generated by the vibration power generation element 11 is supplied to the signal processing unit 14 and the transmitter 15 included in the tire side device 1 via the rectification unit 121 and the power storage unit 122.
- the power supply circuit 12 includes the power storage unit 122, when the vibration power generation element 11 is generating excessive power, the surplus is stored, and when the power generation amount is insufficient, the shortage is stored. You can make up for it.
- the signal processing unit 14 mainly includes a microcomputer, and each includes a well-known CPU, a memory such as a ROM / RAM / EEPROM, an I / O, and a bus connecting them.
- the signal processing unit 14 performs processing for extracting data necessary for estimating the friction coefficient between the road surface 7 and the tire 6 and the air pressure of the tire 6 from the time change of the voltage sequentially input from the vibration power generation element 11. To do.
- the signal processing unit 14 includes a road surface contact section detection unit 141, a high frequency component extraction unit 142, and a contact time measurement unit 144 as functions for performing these processes. In the following, data of time change of the output voltage of the vibration power generation element 11 is treated as vibration data.
- the road surface contact section detection unit 141 contacts the road surface 7 with the tread portion to which the tire side device 1 is attached (hereinafter referred to as the attachment portion 61). And when the mounting portion 61 is separated from the road surface 7 are detected. Then, a period from when the attachment portion 61 contacts the road surface until it is separated from the road surface is detected as a section in contact with the road surface (road surface contact section).
- the point in time when the attachment portion 61 of the tread 60 contacts the road surface 7 (at the time of ground contact) and the time point away from the road surface 7 (at the time of takeoff) are detected as follows.
- FIG. 4 shows a conceptual diagram of the time change (that is, vibration data) of the output voltage of the vibration power generation element 11.
- T1 in FIG. 4 is a point in time when the mounting portion 61 to which the tire-side device 1 is mounted contacts the road surface 7 when the tire 6 rotates.
- T2 is the time when the attachment portion 61 is separated from the road surface 7.
- the output voltage of the vibration power generation element 11 at T1 and T2 is larger than the amplitude of the output voltage before and after that as follows.
- the attachment portion 61 of the tire-side device 1 in the tread 60 is grounded as the tire 6 rotates, the vicinity of the attachment portion 61 that has been a substantially cylindrical surface is pressed and deformed into a flat shape.
- the reason why the output voltage at T1 is larger than the output voltage immediately before T1 is to receive an impact when pressed.
- the vicinity of the attachment portion 61 moves away from the grounding surface, the pressure is released and the plane shape returns to a substantially cylindrical shape.
- the reason why the output voltage becomes larger than the output voltage after T2 at T2 is to receive an impact when it is released from the pressed state and returned to its original state.
- the sign of the output voltage is also opposite. Further, during the period from the time when the road surface 7 is separated from the road surface 7 until the contact with the road surface 7 again (S2 in FIG. 4), the vibration component in the tire tangential direction in the mounting portion 61 of the vibration in the vertical direction of the road surface due to the unevenness of the road surface 7 or the like. Detected.
- the road surface contact section detection unit 141 determines that the attachment portion 61 is grounded / separated when the output voltage of the vibration power generation element 11 is equal to or higher than a predetermined threshold Th. It is determined that The threshold value Th may be appropriately set by a test or the like. For example, the threshold value Th may be set to twice the average value of the amplitude output when the vehicle is traveling.
- the road surface contact section detection unit 141 that performs the process of detecting the contact point is the contact point time point detection unit 141A
- the road surface contact section detection unit 141 that performs the process of detecting the takeoff point is the contact point point. It is the detection unit 141B.
- the high-frequency component extraction unit 142 extracts the high-frequency component (high-frequency vibration data) of the portion corresponding to the point of departure from the contact point detected by the road surface contact section detection unit 141 in the vibration data of the vibration power generation element 11 and transmits To the machine 15.
- a wavelet filter is used as the high-frequency component extracting unit 142, but other known high-pass filters may be used.
- the contact time measuring unit 144 measures the time from the contact point detected by the road surface contact section detector 141 to the takeoff point, and outputs the contact time (S1 in FIG. 4) to the transmitter 15.
- the high-frequency component of the vibration data from the time of contact to the time of takeoff and the data (detection data) such as the contact time S1 generated by the signal processing unit 14 are transmitted to the vehicle side device 2 via the transmitter 15. Is done. Communication between the transmitter 15 and the receiver 21 included in the vehicle-side device 2 may be performed by a known short-range wireless communication technology such as Bluetooth (registered trademark).
- the detection data is transmitted at the timing when the contact time S1 per one rotation of the tire 6 and the high-frequency vibration data can be generated.
- the vehicle side device 2 is provided in the own vehicle outside the tire 6 and includes a receiver 21, a wheel speed detection unit 22, a signal processing unit 23, and a loaded weight detection unit 24.
- the receiver 21 is a device for receiving detection data transmitted from the transmitter 15 included in the tire side device 1. The detection data received by the receiver 21 is sequentially output to the signal processing unit 23 every time it is received.
- the wheel speed detection unit 22 is a known wheel speed sensor that detects the rotation speed of the wheel, and outputs the rotation speed of the tire 6 to the signal processing unit 23.
- the wheel speed detection unit 22 for example, a type that detects a change in magnetic flux due to teeth formed on the outer periphery of a rotor that rotates with an axle using a pickup coil or a Hall element can be used.
- the loading weight detection unit 24 detects the loading weight of the own vehicle and outputs it to the signal processing unit 23.
- the loaded weight detection unit 24 may be configured to be estimated from vehicle gear, accelerator state, engine speed, acceleration, and the like as disclosed in, for example, Japanese Patent Application Laid-Open No. 2010-243305. Further, other known load weight sensors may be used.
- the signal processing unit 23 is mainly composed of a microcomputer, and includes a known CPU, a memory such as a ROM / RAM / EEPROM, an I / O, and a bus for connecting them.
- detection data is sequentially input from the receiver 21, and the wheel speed of the tire 6 is sequentially input from the wheel speed acquisition unit 22 (for example, every 100 msec).
- the signal processing unit 23 performs processing for estimating the friction coefficient between the road surface 7 and the tire 6 and the air pressure of the tire 6 from various data.
- the signal processing unit 23 includes a friction coefficient calculation unit 231 and an air pressure calculation unit 232 as functions.
- the friction coefficient estimator 231 estimates the friction coefficient between the road surface 7 and the tire 6 by comparing the amplitude level at the time of takeoff in the high-frequency vibration data with a predetermined threshold (friction determination threshold). This is because, as disclosed in Patent Document 1, the road surface having a high coefficient of friction such as a dry asphalt road surface and the road surface having a low coefficient of friction have different vibration waveforms generated in the tread 60. The estimation is performed by focusing on the point that the difference in the amplitude level of the high frequency component at the time is significant.
- the friction determination threshold value is such that the amplitude level of the section where the attachment portion 61 is not in contact with the road surface 7 (S2 in FIG. 4) and the amplitude level at the time of contact (T1) or the time of takeoff (T2) can be identified. It may be determined in advance by a test or the like.
- the friction coefficient estimator 231 compares the amplitude level at the time of takeoff in the high-frequency vibration data with a friction determination threshold predetermined by a test or the like. When the high frequency amplitude level at the time of takeoff is larger than the friction determination threshold, it is determined that the friction coefficient between the road surface 7 and the tire 6 is high. When the amplitude level at the time of takeoff in the high-frequency vibration data is smaller than the friction determination threshold, it is determined that the friction coefficient between the road surface 7 and the tire 6 is low. In addition, it is good also as a structure which has beforehand the table which shows the correspondence of a friction coefficient and the amplitude level at the time of takeoff, and estimates the friction coefficient according to the amplitude level at the time of takeoff from this correspondence.
- the vibration generated in the tread 60 is greatly influenced by the wheel speed in addition to the friction coefficient with the road surface 7.
- the larger the wheel speed the larger the amplitude of vibration that occurs when the mounting portion 61 is taken off.
- the influence of the wheel speed is apparent not only at the time of takeoff, but also at the vibration amplitude at the time of ground contact. Therefore, the friction coefficient estimation unit 231 may correct the amplitude level at the time of takeoff in the high-frequency vibration data by using the wheel speed acquired by the wheel speed detection unit 22 and the amplitude level at the time of ground contact. In this case, the influence on the friction coefficient due to the wheel speed is reduced by correcting the amplitude level at the time of takeoff smaller as the wheel speed is higher.
- the reference ground amplitude level is set in advance as a reference for the amplitude level at the time of grounding, and the actually detected amplitude level at the time of grounding is determined according to the degree of divergence from the amplitude level at the time of grounding. What is necessary is just to correct
- the friction coefficient may be estimated from the corrected high frequency amplitude level at the time of takeoff and the friction determination threshold.
- the friction coefficient estimated by the friction coefficient estimation unit 231 is output to various control systems such as an ABS system.
- the air pressure estimation unit 232 estimates the air pressure of the tire 6 from the contact time S1 and the wheel speed.
- the contact length calculation unit 232A included in the air pressure estimation unit 232 calculates the traveling speed of the host vehicle from the wheel speed, and the length in the traveling direction in which the tire 6 is in contact with the road surface from the traveling speed and the contact time S1 ( Calculate the contact length). For example, when the traveling speed is 60 km / h and the contact time S1 is 60 msec, the contact length can be obtained as 10 cm.
- the air pressure estimation unit 232 compares the normal ground contact length set in advance with the ground contact length calculated from the detected ground contact time S1 and the wheel speed, and the calculated ground contact length is the reference ground contact. If it is longer than the length, it is estimated that the air pressure has decreased according to the difference. When the calculated contact length is shorter than the reference contact length, it is estimated that the air pressure is high according to the difference.
- the reference ground contact length may be a value set in advance by a test or the like, and of course is not limited to the above-described value.
- multiple reference ground lengths may be set.
- two types of reference ground contact lengths are set, and these are defined as a first reference ground contact length (for example, 12 cm) and a second reference ground contact length (for example, 8 cm: second reference ground contact length ⁇ first reference ground contact length).
- first reference ground contact length for example, 12 cm
- second reference ground contact length for example, 8 cm: second reference ground contact length ⁇ first reference ground contact length.
- the contact length is also affected by the load on the tire (including the weight of the load or the occupant loaded on the vehicle and the weight of the vehicle itself).
- the load weight is different from the weight of the vehicle itself, and is likely to fluctuate every time the vehicle travels. Therefore, the air pressure estimation unit 232 may correct the reference ground contact length using the vehicle load weight acquired from the load weight detection unit 24, and may estimate the air pressure using the corrected reference contact length. For example, when the current loading weight is larger than the loading weight when the reference ground contact length is set (hereinafter referred to as the reference loading weight), the reference ground contact length may be corrected according to the difference. In addition, when the current load weight is smaller than the reference load weight, the reference contact length may be corrected so as to be shortened according to the difference.
- the reference load weight may be set assuming that no people or luggage are loaded (that is, only the weight of the vehicle itself rests on the tire), or one standard adult rides It may be set on the assumption of the current state.
- a load sensor for detecting the load on the tire may be separately attached, and the correspondence between the contact length and the air pressure may be corrected using the detected value.
- the reference contact length may be corrected so as to increase as the detection value of the load sensor increases.
- the vibration power generation element 11 detects the vibration of the tread 60 when the counter electrode P vibrates relative to the electret electrode E due to the vibration of the mounting portion 61. Further, the signal processing unit 14 and the transmitter 15 are operated by the generated power. Thus, since the element which detects vibration serves also as a role which supplies the electric power for driving the tire side apparatus 1, it becomes unnecessary to provide the battery for driving the tire side apparatus 1 separately. Therefore, the tire side device 1 (a member attached to the inside of the tire of the tire device 100) can be reduced in size. For example, in the conventional configuration, in the tire side device 1, a battery for driving the tire side device occupies about half of the entire space. That is, the tire side device 1 can be downsized to about half by adopting the configuration as in the present embodiment.
- the signal processing unit 14 of the tire side device 1 performs processing for extracting information necessary for estimating the tire state
- the signal processing unit 23 of the vehicle side device 2 performs wheel speed and the like.
- the process of calculating the coefficient of friction and the air pressure using the above data was performed. Thereby, complicated processing can be collectively performed in the signal processing unit 23 of the vehicle-side device 2.
- Various functions (road surface section detecting unit 141, contact time measuring unit 144, high frequency component extracting unit 142) provided in the signal processing unit 14 of the tire side device 1 are provided in the signal processing unit 23 of the vehicle side device 2. Also good. Various functions (friction coefficient estimation unit 231 and air pressure estimation unit 232) provided in the signal processing unit 23 of the vehicle side device 2 may be provided in the signal processing unit 14 of the tire side device 1.
- the configuration in which the movable substrate (the counter electrode substrate 11P in the present embodiment) is supported by the spring K1 is exemplified.
- the vibration power generation element 11 when the movable substrate 11P is supported by a single spring, the vibration power generation element 11 detects vibration with high sensitivity with respect to vibration in a specific frequency band corresponding to the spring constant of the spring (and Generate electricity. Based on various tests, the inventors have found that the frequency of vibrations that occur in the tread 60 during traveling of the vehicle other than the time of ground contact and the time of takeoff (that is, vibrations in the section S2 in FIG. 4) is in the range of approximately 10 to 100 Hz. I figured out that.
- the power generation efficiency of the vibration power generation element 11 can be increased by designing the spring constant so that the natural frequency of the movable substrate 11P supported by the spring is included in the range of 10 to 100 Hz.
- the present disclosure is not limited to the above-described embodiment, and can be modified or expanded as follows, for example.
- the vibration frequency corresponding to the section S2 in FIG. 4 described above is also affected by the rotational speed of the tire (1 to 20 Hz), the road surface shape (irregularities, etc.) and the state (whether there is freezing, etc.) Other values (100 to 200 Hz, etc.) may be used.
- the distribution of the frequency of vibration generated in the tread of each tire differs between a vehicle such as a long-distance truck that mainly travels on a highway and a vehicle that mainly travels on an undeveloped road surface such as a gravel road. Is expected. Therefore, the natural frequency of the movable substrate 11P may be designed to be included in the range of the frequency of vibration generated in the tread 60 in an environment where the vehicle including the tire device 100 travels on a daily basis.
- the inventors have found from various tests that the vibration generated in the tread exists in the range of 100 Hz to 10 kHz at the time of ground contact, at the time of takeoff, and in the vicinity thereof. Therefore, a configuration capable of detecting with high sensitivity even for vibrations in these frequency bands is preferable. In other words, by outputting voltages corresponding to vibrations in these frequency bands, it is possible to accurately detect the ground contact point and the takeoff point of the mounting portion 61 in the rotational movement of the tire. As described above, the vibration generated in the tread in the vicinity of the ground contact point and the takeoff point is that the attachment portion 61 is deformed when the attachment portion 61 is pressed or released from the press. to cause.
- the movable substrate 11P may be supported by a ball or a cylindrical member (B1) that rotates in the vibration detection direction with respect to the fixed substrate (the electret electrode substrate 11E in the present embodiment).
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Abstract
Description
(変形例)
本開示は、上記した実施形態にのみ限定されるものではなく、例えば、以下のように変形又は拡張することができる。
Claims (9)
- タイヤの内部に配置され、前記タイヤのトレッドに生じる振動の時間変化に応じた電圧を出力する振動発電素子(11)と、
前記タイヤの内部に配置され、前記振動発電素子の出力電圧に対して信号処理を行う信号処理部(14)と、
前記タイヤの内部に配置され、前記信号処理部で信号処理されたデータを前記タイヤ外部に設けられた装置へ送信する送信機(15)と、
を備えたタイヤ装置において、
前記信号処理部および前記送信機は、前記振動発電素子の発電した電力によって駆動するタイヤ装置。 - 請求項1において、
前記振動発電素子の出力電圧の時間変化から、前記トレッドにおいて前記振動発電素子が取り付けられている取付部分(61)が路面と接触した時点を検出する接地時点検出部(141A)と、
前記振動発電素子の出力電圧の時間変化から、前記取付部分が路面から離れた時点である離地時点を検出する離地時点検出部(141B)と、
前記接地時点検出部が検出した前記接地時点から前記離地時点検出部が検出した前記離地時点までの接地時間を計測する接地時間計測部(144)と、
前記タイヤの回転速度を検出する車輪速検出部(22)と、
前記接地時間計測部が算出した前記接地時間と前記車輪速検出部が検出した前記タイヤの前記回転速度から、前記取付部分が路面に接触していた区間の長さである接地長を算出する接地長算出部(232A)と、
前記接地長算出部が算出した前記接地長から前記タイヤの空気圧を推定する空気圧推定部(232)と、を備えるタイヤ装置。 - 請求項2において、
前記空気圧推定部は、前記タイヤの空気圧に応じて予め設定された接地長である基準接地長を少なくとも1つ記憶しており、前記基準接地長と、前記接地長算出部で算出された接地長とを比較することで前記タイヤの空気圧を推定するタイヤ装置。 - 請求項3において、
前記車両の積載重量を検出する積載重量検出部(24)を備え、
前記空気圧推定部は、前記積載重量検出部が検出した前記車両の積載重量が、予め設定された積載重量である基準積載重量よりも大きい場合は、前記基準接地長をより長くし、また、前記車両の積載重量が前記基準積載重量よりも小さい場合は、前記基準接地長をより短くするように補正するタイヤ装置。 - 請求項1から4のいずれか1項において、
前記振動発電素子の出力電圧の高周波成分を抽出する高周波成分抽出部(142)と、
前記高周波成分抽出部が抽出した高周波成分の振幅の大きさから、前記路面と前記タイヤ間の摩擦係数を推定する摩擦係数推定部(231)と、を備えるタイヤ装置。 - 請求項1から4のいずれか1項において、
前記振動発電素子の出力電圧は、整流部(121)および蓄電部(122)を備える電力供給回路(12)へと入力され、
前記電力供給回路は、前記振動発電素子より入力された電力を、前記信号処理部(14)および前記送信機(15)に供給するタイヤ装置。 - 請求項1から5のいずれか1項において、
前記振動発電素子は、前記トレッドに対して固定されている固定基板(11E)と、前記固定基板に対して対向して設置され、かつ、前記固定基板に対してタイヤ接線方向に可動する可動基板(11P)と、を備え、前記可動基板が前記固定基板に対する位置が変化することで発電する振動発電素子であって、
前記可動基板の固有振動数が、1~20Hzで回転する前記タイヤの回転運動および路面の凹凸に起因して前記トレッドに生じる振動の周波数帯に含まれる構造を備えるタイヤ装置。 - 請求項1から6のいずれか1項において、
前記振動発電素子は、前記トレッドに対して固定されている固定基板(11E)と、前記固定基板に対して対向して設置され、かつ、前記固定基板に対してタイヤ接線方向に可動する可動基板(11P)と、を備え、前記可動基板が前記固定基板に対する位置が変化することで発電する振動発電素子であって、
前記可動基板の固有振動数が、前記トレッドにおいて前記振動発電素子が取り付けられている取付部分が変形する際に生じる振動の周波数帯に含まれる構造を備えるタイヤ装置。 - 請求項7において、
前記振動発電素子は、前記可動基板の固有振動数が1~20Hzで回転する前記タイヤの回転運動および路面の凹凸に起因して前記トレッドに生じる振動の周波数帯に含まれる構造と、前記可動基板の固有振動数が前記トレッドにおいて前記振動発電素子が取り付けられている取付部分が変形する際に生じる振動の周波数帯に含まれる構造と、を両立する構造を備えるタイヤ装置。
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9713944B2 (en) | 2014-03-18 | 2017-07-25 | Denso Corporation | Tire condition detection device |
US9950578B2 (en) | 2014-05-14 | 2018-04-24 | Denso Corporation | Tire air pressure detection device |
US10029681B2 (en) | 2014-03-18 | 2018-07-24 | Denso Corporation | Vehicle erroneous start control device |
US10086842B2 (en) | 2014-03-18 | 2018-10-02 | Denso Corporation | Road surface condition estimation device |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6235885B2 (ja) | 2013-12-03 | 2017-11-22 | 株式会社Soken | 車両用制御装置 |
DE102015216587A1 (de) * | 2015-08-31 | 2017-03-02 | Robert Bosch Gmbh | Anordnung zur Bestimmung der Geschwindigkeit eines Fahrzeugs und Fahrzeug |
JP6547793B2 (ja) * | 2016-08-12 | 2019-07-24 | 株式会社デンソー | タイヤマウントセンサ、ダイアグ履歴記憶装置およびダイアグ報知装置 |
JP6782622B2 (ja) * | 2016-12-13 | 2020-11-11 | Toyo Tire株式会社 | タイヤの接地状態測定装置 |
CN111231588B (zh) * | 2020-01-17 | 2022-06-03 | 新石器慧通(北京)科技有限公司 | 胎压监测方法、装置、车载设备和存储介质 |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09237398A (ja) * | 1996-02-29 | 1997-09-09 | Yokohama Rubber Co Ltd:The | タイヤ装着用トランスポンダ及びトランスポンダ装着タイヤ |
JP2003065871A (ja) * | 2001-08-29 | 2003-03-05 | Nissan Motor Co Ltd | 車輪タイヤの接地長検出装置 |
WO2005016670A1 (ja) * | 2003-08-19 | 2005-02-24 | Kabushiki Kaisha Bridgestone | センサ内蔵タイヤ及びタイヤ状態推定方法 |
JP2005186930A (ja) * | 2003-12-22 | 2005-07-14 | Samsung Electronics Co Ltd | 自家発電型センシングモジュール及びそれを使用するタイヤ空気圧モニタリングシステム |
JP2007514176A (ja) * | 2003-12-11 | 2007-05-31 | コンティ テミック マイクロエレクトロニック ゲゼルシャフト ミット ベシュレンクテル ハフツング | センサトランスポンダ及びタイヤ接地長及びタイヤ荷重の測定方法 |
JP2007137086A (ja) * | 2005-11-14 | 2007-06-07 | Bridgestone Corp | 路面摩擦状態推定方法、路面摩擦状態推定装置、及び、路面摩擦状態推定用タイヤ |
JP2010533844A (ja) * | 2007-07-18 | 2010-10-28 | ピレリ・タイヤ・ソチエタ・ペル・アツィオーニ | 車両の走行中のタイヤの動作パラメータを決定するための方法およびシステム |
JP2012218682A (ja) * | 2011-04-13 | 2012-11-12 | Honda Motor Co Ltd | 車輪荷重値算出装置 |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4439985B2 (ja) | 2004-04-20 | 2010-03-24 | 株式会社ブリヂストン | 路面摩擦係数の推定方法、路面摩擦係数推定装置、及び、車両制御装置 |
JP4241587B2 (ja) * | 2004-11-25 | 2009-03-18 | トヨタ自動車株式会社 | 車輪状態監視装置および車輪状態監視方法 |
ES2531079T3 (es) * | 2005-06-17 | 2015-03-10 | Bridgestone Corp | Procedimiento de estimación del estado de la superficie de una carretera, neumático de estimación del estado de la superficie de una carretera, dispositivo de estimación del estado de la superficie de una carretera y dispositivo de control de vehículo |
JP5309763B2 (ja) | 2008-07-29 | 2013-10-09 | 横浜ゴム株式会社 | タイヤの接地長算出方法および装置 |
JP5265440B2 (ja) | 2009-04-06 | 2013-08-14 | 矢崎エナジーシステム株式会社 | 積載重量推定装置 |
JP2011221002A (ja) * | 2010-03-25 | 2011-11-04 | Sanyo Electric Co Ltd | 振動検出装置、空気圧検出端末および加速度検出システム |
JP6318743B2 (ja) | 2014-03-18 | 2018-05-09 | 株式会社Soken | タイヤ状態検出装置 |
JP6281346B2 (ja) | 2014-03-18 | 2018-02-21 | 株式会社Soken | 路面状況推定装置 |
JP6273937B2 (ja) | 2014-03-18 | 2018-02-07 | 株式会社Soken | 路面状況推定装置 |
JP6330398B2 (ja) | 2014-03-18 | 2018-05-30 | 株式会社Soken | 車両誤発進抑制装置 |
JP6318835B2 (ja) | 2014-05-14 | 2018-05-09 | 株式会社デンソー | タイヤ空気圧検出装置 |
-
2014
- 2014-03-11 DE DE112014001372.2T patent/DE112014001372T5/de not_active Withdrawn
- 2014-03-11 WO PCT/JP2014/001362 patent/WO2014141690A1/ja active Application Filing
- 2014-03-11 US US14/776,220 patent/US9827815B2/en active Active
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09237398A (ja) * | 1996-02-29 | 1997-09-09 | Yokohama Rubber Co Ltd:The | タイヤ装着用トランスポンダ及びトランスポンダ装着タイヤ |
JP2003065871A (ja) * | 2001-08-29 | 2003-03-05 | Nissan Motor Co Ltd | 車輪タイヤの接地長検出装置 |
WO2005016670A1 (ja) * | 2003-08-19 | 2005-02-24 | Kabushiki Kaisha Bridgestone | センサ内蔵タイヤ及びタイヤ状態推定方法 |
JP2007514176A (ja) * | 2003-12-11 | 2007-05-31 | コンティ テミック マイクロエレクトロニック ゲゼルシャフト ミット ベシュレンクテル ハフツング | センサトランスポンダ及びタイヤ接地長及びタイヤ荷重の測定方法 |
JP2005186930A (ja) * | 2003-12-22 | 2005-07-14 | Samsung Electronics Co Ltd | 自家発電型センシングモジュール及びそれを使用するタイヤ空気圧モニタリングシステム |
JP2007137086A (ja) * | 2005-11-14 | 2007-06-07 | Bridgestone Corp | 路面摩擦状態推定方法、路面摩擦状態推定装置、及び、路面摩擦状態推定用タイヤ |
JP2010533844A (ja) * | 2007-07-18 | 2010-10-28 | ピレリ・タイヤ・ソチエタ・ペル・アツィオーニ | 車両の走行中のタイヤの動作パラメータを決定するための方法およびシステム |
JP2012218682A (ja) * | 2011-04-13 | 2012-11-12 | Honda Motor Co Ltd | 車輪荷重値算出装置 |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9713944B2 (en) | 2014-03-18 | 2017-07-25 | Denso Corporation | Tire condition detection device |
US10029681B2 (en) | 2014-03-18 | 2018-07-24 | Denso Corporation | Vehicle erroneous start control device |
US10086842B2 (en) | 2014-03-18 | 2018-10-02 | Denso Corporation | Road surface condition estimation device |
US9950578B2 (en) | 2014-05-14 | 2018-04-24 | Denso Corporation | Tire air pressure detection device |
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