JP2017132348A - Tire position registration system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire position registration system capable of determining a tire position accurately in a short time regardless of whether a road is flat or a slope.SOLUTION: An inclination angle detection unit 27 outputs a detection signal Sθ according to an amount of inclination of a vehicle body 5 to a TPMS receiver 12. A correction processing unit 28 shifts axle rotation information Dc (a pulse count value) acquired from respective axle rotation detection units 22a-22d by a pulse count value according to the detection signal Sθ, thereby correcting the axle rotation information Dc based on the detection signal Sθ input from the inclination angle detection unit 27. A position determination unit 23 uses the corrected axle rotation information Dc, and confirms synchronization between a valve ID transmitted from a tire valve 4 at a specific position in rotation direction and the axle rotation information Dc so as to determine positions of the respective tires 2a-2d.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a tire position registration system that registers a mounting position of a tire with respect to a vehicle body in a receiver.

  Conventionally, as one function of a tire pressure monitoring system, a tire position registration system that automatically registers a tire valve ID (valve ID) in a receiver without using a trigger generator such as an initiator is well known (Patent Literature). 1 etc.). If the initiator is not required for registering the valve ID in the receiver, the number of components mounted on the vehicle can be reduced.

Special table 2011-527971 gazette

  In this type of tire position registration system, for example, after rotating a tire or replacing a tire with a new tire, the new tire position cannot be displayed on the instrument panel or the like immediately after the start of traveling. The user feels uncomfortable. Therefore, it is necessary to complete the determination of the changed tire position in a short time and register it in the receiver. Further, the travel path of the vehicle is not limited to a flat road, and may travel on a slope. For this reason, there was a need to specify the tire position accurately and in a short time regardless of the condition of the road.

  An object of the present invention is to provide a tire position registration system capable of accurately determining a tire position in a short time, not limited to a flat road or a slope.

  A tire position registration system that solves the above problem is transmitted when the tire valve is at a specific position in the rotational direction when monitoring the air pressure of the tire based on the electric wave related to the air pressure from the tire valve attached to each tire. The process of acquiring axle rotation information of each tire when receiving the radio wave to be received by the receiver of the vehicle body is performed every time the radio wave is received from each tire valve, and the synchronization between the tire valve and the axle is confirmed. A tire position is specified and registered in the receiver, and an inclination angle detection unit that detects an inclination generated in a vehicle body, and a radio wave transmitted from the tire valve at the specific position is received by the receiver. A correction processing unit that corrects the axle rotation information obtained upon reception based on a detection signal of the tilt angle detection unit.

  According to this configuration, the inclination angle generated in the vehicle body is detected by the inclination angle detection unit, and the axle rotation information is corrected based on the detection signal of the inclination angle detection unit. For this reason, since the axle rotation information takes a value excluding the influence of the inclination angle, the calculation of the tire position can be suitably performed. As a result, the rotational position where the radio transmission of the tire valve should be detected falls within a tolerance that is assumed in advance. Therefore, it is possible to accurately determine the tire position in a short time, not limited to a flat or sloped road.

  In the tire position registration system, it is preferable that the inclination angle detection unit is a sensor that detects an inclination amount generated in a front-rear direction of the vehicle body. According to this configuration, the difference between the rotational position at which the tire valve radio wave transmission should be detected when traveling on a slope and the median value of the rotational position at which the tire valve radio wave transmission is actually detected, that is, the inclination angle is detected more correctly. This is advantageous.

  In the tire position registration system, the position determination unit of the receiver confirms the tendency of which axle rotation information of each axle is synchronized for each tire valve ID. It is preferable to determine the mounting position. According to this configuration, the tire position can be accurately determined by a calculation method of confirming the synchronization tendency.

  In the tire position registration system, the axle rotation information is a pulse count value of a pulse signal output from a rotation speed detection unit provided on each axle, and the correction processing unit receives the pulse meter acquired at the time of radio wave reception. It is preferable that the numerical value is corrected based on the detection signal of the tilt angle detection unit, and the tire position is determined based on the corrected pulse count value. According to this configuration, the tilt angle can be corrected by a simple method in which the pulse count value is changed according to the tilt angle. Therefore, it is further advantageous to make the rotational position where the transmission of the radio wave of the tire valve should be detected fall within a tolerance that is assumed in advance.

  According to the present invention, the tire position can be determined accurately and in a short time, not limited to a flat road or a slope.

The lineblock diagram of the tire position registration system of one embodiment. (A)-(d) is a schematic diagram when each tire valve transmits a radio wave at a specific position. (A), (b) is a communication sequence diagram of a tire valve. The distribution diagram of axle rotation information (pulse count value) of each wheel in a certain valve ID. A distribution table of axle rotation information (pulse count value) created for each valve ID. (A) is a schematic diagram of radio transmission of a tire valve when traveling on a flat road surface, (b) is a schematic diagram of radio transmission of a tire valve when traveling on a slope road surface. Explanatory drawing which shows the method of correction | amendment of axle shaft rotation information.

Hereinafter, an embodiment of a tire position registration system will be described with reference to FIGS.
As shown in FIG. 1, the vehicle 1 includes a tire pressure monitoring system (TPMS) 3 that monitors the air pressure and the like of each tire 2 (2 a to 2 d). The tire pressure monitoring system 3 includes tire valves 4 (4a to 4d) attached to the tires 2a to 2d. The tire valve 4 is a tire valve sensor in which a tire plug is provided with a sensor and a communication function. The tire pressure monitoring system 3 transmits a radio wave Sva (first radio wave Sva1, similarly hereinafter) associated with at least pressure data and ID from the tire valves 4a to 4d to the vehicle body, and each tire 2a to 2d in the vehicle body 5 is transmitted. Monitor the air pressure.

  The tire valve 4 detects a controller 6 that controls the operation of the tire valve 4, a pressure detection unit 7 that detects tire air pressure, a temperature detection unit 8 that detects the temperature of the tire 2, and gravity that occurs in the tire valve 4. And a transmission antenna 10 capable of transmitting radio waves in the tire valve 4. A valve ID is written and stored in the memory 11 of the controller 6 as a unique ID of each tire valve 4. The pressure detector 7 is preferably a pressure sensor, for example. The temperature detector 8 is preferably a temperature sensor, for example. The gravity detector 9 is preferably an acceleration sensor (G sensor), for example. The transmission antenna 10 is preferably capable of transmitting a radio wave of, for example, a UHF (Ultra High Frequency) band.

  The vehicle body 5 includes a receiver (hereinafter referred to as a TPMS receiver 12) that monitors the air pressure of the tires 2a to 2d by receiving the first radio wave Sva1 transmitted from the tire valves 4a to 4d. The TPMS receiver 12 includes a tire pressure monitoring ECU (Electronic Control Unit) 13 that controls the operation of the TPMS receiver 12 and a receiving antenna 14 that enables radio waves to be received by the TPMS receiver 12. In the memory 15 of the tire pressure monitoring ECU 13, valve IDs acquired from the respective tire valves 4a to 4d are written and stored in association with tire positions. The TPMS receiver 12 is connected to a display unit 16 that displays the monitoring result of the tire air pressure. It is preferable that the display part 16 is installed in the instrument panel in a vehicle, for example.

  When the receiving antenna 14 receives the first radio wave Sva1 transmitted from the tire valves 4a to 4d at a certain timing, the TPMS receiver 12 collates the valve ID in the first radio wave Sva1, and if the valve ID collation is established, Check the pressure data (air pressure data) in the same radio wave. If the air pressure is equal to or lower than the low pressure threshold, the TPMS receiver 12 displays on the display unit 16 that the tire air pressure is low. The TPMS receiver 12 performs the tire air pressure determination for each received first radio wave Sva1, and monitors the air pressure of the tires 2a to 2d.

  The tire pressure monitoring system 3 associates the valve IDs of the tire valves 4a to 4d with the axles 18 (18a to 18d) at the respective mounting positions on the front, rear, left and right of the vehicle body 5 so that the tire mounting position is determined by the TPMS receiver 12. Is provided with a tire position registration function for automatically registering, a so-called auto location function (tire position registration system 17). The tire position registration system 17 of the present example uses a TPMS receiver of the vehicle body 5 to transmit a radio wave Sva (second radio wave Sva2, hereinafter the same) transmitted when the tire valves 4a to 4d (tires 2a to 2d) are at specific positions in the rotational direction. 12 is performed every time the second radio wave Sva2 is received from each of the tire valves 4a to 4d, and the tire valves 4a to 4d and the axles 18a to 18d are acquired. The tire position is specified by checking the synchronization with the TPMS receiver 12 and registered.

  The vehicle 1 includes an axle rotation detection unit 22 (22a to 22d) for each of the axles 18a to 18d. The axle rotation detection unit 22 is preferably an ABS (Antilock Brake System) sensor provided on each axle 18a to 18d. In this case, the axle rotation information Dc is the number of pulses detected by the ABS sensor, that is, a pulse count value. The axle rotation detection unit 22 outputs a rectangular wave pulse signal to the TPMS receiver 12 by detecting a plurality of (for example, 48) teeth provided on the axles 18 a to 18 d by the sensing unit on the vehicle body 5 side. . At this time, if both the rising and falling edges of the pulse signal are detected, 96 pulses (count value: 0 to 95) per tire rotation can be detected.

  As shown in FIG. 2A, for example, when the right front tire valve 4a takes a specific position, the second radio wave Sva2 including “ID1” that is an ID (valve ID) of the right front tire valve 4a is generated from the right front tire valve 4a. Sent. The specific position is preferably a peak position that is a vertex position in the rotation direction (a 12 o'clock position in the clock). When the TPMS receiver 12 receives the second radio wave Sva2, the axle rotation information Dc-11, Dc-12, Dc-13, and Dc-14 are obtained from the axle rotation detection units 22a to 22d.

  As shown in FIGS. 2B to 2D, this operation is similarly performed for the other tire valves 4b to 4d. That is, the axle rotation information Dc-21, Dc-22, Dc-23, and Dc-24 when the second radio wave Sva2 including "ID2" transmitted from the left front tire valve 4b is received by the TPMS receiver 12 is acquired. Then, the axle rotation information Dc-31, Dc-32, Dc-33, Dc-34 is obtained when the TPMS receiver 12 receives the second radio wave Sva2 including "ID3" transmitted from the right rear tire valve 4c. The axle rotation information Dc-41, Dc-42, Dc-43, and Dc-44 when the second radio wave Sva2 including "ID4" transmitted from the left rear tire valve 4d is received by the TPMS receiver 12 is acquired. To do.

  By the way, since the vehicle 1 travels in a curve, the tires 2a to 2d are structured to rotate independently. Therefore, after traveling for a certain amount of time, the tires 2a to 2d take different rotational positions with respect to the start of traveling. Thereby, it can be grasped which axles 18a to 18d are associated with ID1 to ID4. In this example, this principle is used to specify the relationship between ID1 to ID4 and the axles 18a to 18d, that is, the tire position.

  Returning to FIG. 1, the tire position registration system 17 includes a position determination unit 23 that performs a tire position determination operation. The position determination unit 23 is provided in the TPMS receiver 12. The position determination unit 23 acquires the axle rotation information Dc when the second radio wave Sva2 including the valve ID is received from the tire valve 4 from each of the axle rotation detection units 22a to 22d, and this operation is performed with the second radio wave Sva2 (valve). ID) is repeatedly received, and the tire position is determined by checking the tendency of which valve ID is synchronized with which axle rotation information Dc.

  As shown in FIG. 3 (a), the tire valve 4 preferably takes alternately a first time period T1 of a short time during which radio waves can be transmitted and a second time period T2 of a long time during which radio waves are not transmitted. The first time period T1 is preferably “1 second”, for example. The second time period T2 is preferably “30 seconds”, for example. Thus, the tire valve 4 repeats the operation of transmitting radio waves during a limited time of 1 second with an interval of about 30 seconds.

  As shown in FIG. 3 (b), the tire valve 4 detects a certain number of times (a plurality of times) of peaks in a predetermined time zone retroactive from the start point T1a of the first time zone T1. When the tire valve 4 is in the first time zone T1 in which radio waves can be transmitted, the one or more pieces of specific position information Dtm held so far are used as the second radio wave Sva2 together with the valve ID by the number of the specific position information Dtm. Send. At this time, the tire valve 4 may continuously transmit the second radio wave Sva2 so as to finish transmitting the second radio wave Sva2 for one packet during the first time period T1. Each second radio wave Sva2 has a time length of about 10 ms, for example, and is repeatedly transmitted at intervals of about 100 ms.

  As illustrated in FIG. 4, the position determination unit 23 acquires the axle rotation information Dc of each axle rotation detection unit 22a to 22d every time the second radio wave Sva2 is received. In this example, the axle rotation information Dc is calculated backward from the specific position information Dtm, and a reverse calculation value is calculated for each specific position information Dtm. And the position determination part 23 takes the statistics of these back calculation values, and adds the statistics every time it receives each 2nd electromagnetic wave Sva2 of a packet unit, and determines a tire position. That is, as shown in the figure, the distribution of the first packet is calculated, and if the tire position is not fixed at the first packet, the distribution of the second packet is added to the first packet and the tire position is determined. The same processing is repeated after the third packet, and the distribution is updated, and the tire position is determined from this distribution.

  As shown in FIG. 5, a distribution table 25 as shown in FIG. 5 is created for each valve ID. The position determination unit 23 performs absolute evaluation for determining the legitimacy of the distribution independently for each axle rotation information Dc and relative evaluation for determining the legitimacy of the distribution among the plurality of axle rotation information Dc. It is preferable to determine the tire position based on the result. Relative evaluation is an index for judging whether the own wheel is compared with the other wheel and is sufficiently synchronized with the other wheel. In this example, “average of deviation” and “standard deviation” are given as examples of distribution. The average deviation and standard deviation are smaller as the determination result is better.

  In the case of the example of FIG. 6, the pulse count values of the left front axle 18b in ID1 are collected in the vicinity of “20”, so the bias value of the left front axle 18b in ID1 is within the threshold, and the left front axle 18b satisfies absolute evaluation in ID1 To do. On the other hand, in ID1, since each pulse count value of the right front axle 18a, the right rear axle 18c, and the left rear axle 18d takes a value that does not converge to one value, these bias values take bad values. For this reason, the difference between the deviation value of the left front axle 18b in ID1 and that of the other axle is equal to or greater than the threshold value, so the relative evaluation is also satisfied. Therefore, since it can be confirmed that ID1 is synchronized with the left front axle 18b, these are linked and it is determined that ID1 is the left front tire 2b. Similarly, the tire positions are also determined in ID2 to ID4.

  If the position determination unit 23 cannot determine the positions of all four wheels in one determination, the position determination unit 23 determines the positions of the remaining wheels by the same process. Then, the same processing is repeated until the positions are determined for all four wheels. When the position determination unit 23 completes position determination for all four wheels, the determination result is written in the memory 15 and the tire position is updated. The tire position determination process may be executed each time the ignition switch of the vehicle 1 is turned on, for example.

  As shown in FIG. 6 (a), the tire valve 4 at the time of tire rotation has a rotation position P1 (at which the radio wave transmission of the tire valve 4 is to be detected at a position 180 ° opposite to the contact point between the tire 2 and the road surface. There are black triangles in the figure. Further, the actual tire valve 4 transmits the second radio wave Sva2 within a tolerance d within a predetermined angular range centered on the median value P2 (white triangle in the figure) of the detected rotational position. As shown in the figure, when running on a flat road surface, the tire position of the tire valve 4 overlaps with the rotation position P1 where the radio wave transmission should be detected, and the rotation position P2 where the tire valve 4 actually detects the radio wave transmission overlaps. There is no problem in determining the position.

  However, as shown in FIG. 6 (b), when the vehicle 1 is traveling on a slope having an inclination angle θ, the rotational position P1 where the transmission of the tire valve 4 should be detected is as follows. It is deviated by the inclination angle θ with respect to the median value P2 of the rotational position at which the actual radio transmission of the tire valve 4 is detected. When the tolerance d 'at this time is combined with the tolerance d when running on a flat road surface, the tolerance appears to be widened, which hinders accurate and early determination of the tire position. This example is a technique for dealing with this problem.

  Returning to FIG. 1, the tire position registration system 17 includes an inclination angle detection unit 27 that detects an inclination generated in the vehicle body. The inclination angle detection unit is preferably a sensor (pitch angle sensor) that detects the amount of inclination generated in the front-rear direction of the vehicle body 5. The inclination angle detection unit 27 outputs a detection signal Sθ corresponding to the amount of inclination of the vehicle body 5 to the TPMS receiver 12.

  The tire position registration system 17 uses the axle rotation information Dc obtained when the TPMS receiver 12 receives the second radio wave Sva2 transmitted from the tire valve 4 at the specific position, and the detection signal Sθ of the inclination angle detection unit 27. A correction processing unit 28 is provided for correction based on the above. The correction processing unit 28 of this example is provided in the tire air pressure monitoring ECU 13. The correction processing unit 28 corrects the pulse count value acquired when the second radio wave Sva2 is received by the TPMS receiver 12 based on the detection signal Sθ of the tilt angle detection unit 27, and determines the position using the corrected pulse count value. The part 23 is caused to determine the tire position.

Next, the operation and effect of the tire position registration system 17 will be described with reference to FIGS. 6 and 7.
As shown in FIGS. 6A and 6B, when the power state of the vehicle 1 is operated to, for example, the ACC position or the IG on position, the inclination angle detection unit 27 is activated, and the inclination angle θ generated in the vehicle body 5 is increased. The corresponding detection signal Sθ is output to the TPMS receiver 12. When the position determination unit 23 determines the tire position, the correction processing unit 28 obtains the axle rotation information Dc from the axle rotation detection units 22a to 22d, based on the detection signal Sθ corresponding to the inclination angle θ. The rotation information Dc is corrected, and the position is determined based on the corrected axle rotation information Dc.

  FIG. 7 shows a specific example of tire position determination during running on an inclined road surface. In correcting the inclination angle θ in the tire position determination, the correction processing unit 28 uses the detected axle rotation information Dc (pulse count value) as the detection signal Sθ based on the detection signal Sθ input from the inclination angle detection unit 27. It is moved by the pulse count value corresponding to. Specifically, when the correction processing unit 28 sequentially holds the value of the inclination angle θ input from the inclination angle detection unit 27 and acquires information on a plurality of peak positions (axle rotation information Dc) from the tire valve 4, In correcting the axle rotation information Dc, the axle rotation information Dc is corrected using the data of the inclination angle θ when the peak position is taken.

  Thereby, since each axle rotation information Dc takes a value excluding the influence of the inclination angle θ, it is possible to suitably calculate the tire position determination. Therefore, the rotational position P1 from which the radio wave transmission of the tire valve 4 should be detected falls within a tolerance d (tolerance d at the time of flat running) that is assumed in advance, which is advantageous for specifying the tire position accurately and in a short time. It becomes. That is, even when traveling on a slope, the tire position can be specified at the same speed as when traveling only on a flat road surface.

  The inclination angle detection unit 27 is a sensor (pitch angle sensor) that detects the amount of inclination that occurs in the front-rear direction of the vehicle body 5. As a result, the difference between the rotational position P1 where the radio wave transmission of the tire valve 4 should be detected when traveling on a slope and the median value P2 of the rotational position where the radio wave transmission of the tire valve 4 is actually detected, in this case, the inclination angle θ This is advantageous for more accurately detecting. Therefore, it is more advantageous to specify the tire position accurately and in a short time.

  For each tire valve 4 ID (ID1 to ID4), the position determination unit 23 confirms the tendency of the axle rotation information Dc of which axle 18a to 18d is synchronized, whereby each tire 2a to The mounting position of 2d is determined. The synchronization tendency here is preferably confirmed from the “average deviation” or “standard deviation” as described above. Therefore, the tire position can be accurately determined by a calculation method of confirming the synchronization tendency.

  The axle rotation information Dc is a pulse count value of the pulse signal, and the correction processing unit 28 corrects the pulse count value and determines the tire position based on the corrected pulse count value when determining the tire position. Thereby, the inclination angle θ can be corrected by a simple method of changing the value of the pulse count value according to the inclination angle θ. Therefore, it is further advantageous to make the rotational position P1 from which the radio wave transmission of the tire valves 4a to 4d should be detected fall within the tolerance d assumed in advance.

Note that the embodiment is not limited to the configuration described so far, and may be modified as follows.
When correcting the axle rotation information Dc with the inclination angle θ input from the inclination angle detection unit 27, the correction processing unit 28 obtains, for example, an average inclination angle θ in a certain unit time, and performs correction based on this. May be.

-A specific position is not limited to a peak position, What is necessary is just a certain position on the locus | trajectory of the rotation direction of the tire valve 4. FIG.
The tire valve 4 is not limited to the one that detects the peak position in advance in the second time zone T2 in which radio wave transmission is not performed, and the detection timing of the peak position in the first time zone T1 in which radio wave transmission is possible The second radio wave Sva2 may be transmitted.

The tire valve 4 may periodically transmit the second radio wave Sva2.
The distribution is not limited to variation, average deviation, and standard deviation, and can be changed to other parameters as long as the synchronization between the valve ID and the axle 18 can be determined.

The first radio wave Sva1 and the second radio wave Sva2 may be the same radio wave.
As the tire position determination method, various methods can be applied as long as the information confirms the synchronization between the axle rotation information of the axle 18 and the radio wave transmission at the specific position of the tire valve 4.

The axle rotation detection unit 22 is not limited to the ABS sensor, and can be changed to another sensor as long as it is attached to the vehicle body 5.
The axle rotation detection unit 22 may transmit the axle rotation information Dc to the TPMS receiver 12 by radio.

The axle rotation detection unit 22 may output a plurality of pulse count values detected during a certain time interval to the TPMS receiver 12 as numerical data.
The axle rotation information Dc may use parameters other than the pulse count value.

The inclination angle detection unit 27 is not limited to the pitch angle sensor, and can be changed to various sensors.
The vehicle 1 may be an engine vehicle, a hybrid vehicle, a plug-in hybrid vehicle, an electric vehicle, or a fuel cell vehicle.

Next, technical ideas that can be grasped from the above-described embodiment and other examples will be described below together with their effects.
(A) In the tire position registration system, the correction processing unit obtains the axle rotation information from the axle rotation detection unit triggered by reception of radio waves from the tire valve by the receiver. Axle rotation information is corrected. According to this configuration, since the correction is performed every time the axle rotation information is acquired, the correction can be performed at a suitable timing.

  DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 (2a-2d) ... Tire, 4 (4a-4d) ... Tire valve, 5 ... Vehicle body, 12 ... Receiver (TPMS receiver), 17 ... Tire position registration system, 18 (18a-18d) ... Axle, 22 (22a-22d) ... Axle rotation detection unit, 23 ... Position determination unit, 27 ... Inclination angle detection unit, 28 ... Correction processing unit, Sva ... Radio wave transmitted by tire valve, Sva1 ... First radio wave, Sva2 ... second radio wave, Dc ... axle rotation information, S? ... detection signal of tilt angle detector.

Claims (4)

When monitoring the tire air pressure based on the air pressure related to the air pressure from the tire valve attached to each tire, when the radio wave transmitted when the tire valve is at a specific position in the rotational direction is received by the receiver of the vehicle body A process of acquiring axle rotation information of each tire is performed each time the radio wave is received from each tire valve, and the tire position is identified and registered in the receiver by checking the synchronization between the tire valve and the axle. A tire position registration system,
An inclination angle detection unit for detecting an inclination generated in the vehicle body;
A correction processing unit that corrects the axle rotation information obtained when the receiver receives a radio wave transmitted from the tire valve at the specific position based on a detection signal of the inclination angle detection unit; A tire position registration system characterized by that. The tire position registration system according to claim 1, wherein the inclination angle detection unit is a sensor that detects an inclination amount generated in a front-rear direction of the vehicle body. The position determination unit of the receiver determines a mounting position of each tire by confirming a tendency of which axle rotation information of each axle is synchronized for each tire valve ID. The tire position registration system according to 1 or 2. The axle rotation information is a pulse count value of a pulse signal output from a rotation speed detector provided on each axle,
The correction processing unit corrects the pulse count value acquired at the time of radio wave reception based on a detection signal of the tilt angle detection unit, and determines the tire position based on the corrected pulse count value. The tire position registration system according to claim 1.

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