JP2006193119A - Tire wear detection system and pneumatic tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pneumatic tire which does not damage the tire or a road surface, can easily be adapted to an existing tire, and has high reliability of wear detection of tire. <P>SOLUTION: The pneumatic tire 10 is comprised of a protrusion portion 40 arranged on a groove 30 of a tread part, and a strain sensor 70 arranged on an inner side of the protrusion part 40 in a tire radial direction for detecting strain induced on the protrusion part 40. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a tire wear detection system and a pneumatic tire that detect a wear state of a tire.

  Conventionally, if the remaining groove on the tire surface is reduced too much, it is natural that legal problems will occur, but it has had a great impact on driving safety. When managing such tire wear, the driver or the vehicle operation manager visually checks the tread pattern groove depth or the appearance of slip signs provided on the tire to visually check the tire wear state. Inspecting or checking a dedicated residual groove measuring device (so-called depth gauge) by manually hitting the tire is carried out. When the tread reaches a worn state, it is replaced with a new tire.

  In order to make the slip sign stand out, a technique for coloring the slip sign or embedding a bow to generate an abnormal noise is disclosed (for example, see Patent Document 1).

  Also, when checking the tire wear condition visually or using a depth gauge, if the driver neglects to check or mistakes the check method, leave it even if the tire reaches the wear limit. It is not preferable. In addition, there is a problem in that it takes time for measurement, and it is necessary to pay sufficient attention to safety so that the driver is well notified and does not start during measurement.

For this reason, based on the electrical conduction state, a technique for detecting tire wear (see, for example, Patent Document 2), a light reflecting member having a light reflecting surface is embedded in the tread, and when the tire is worn, A technique (for example, see Patent Document 3) that detects wear of a tire by reflecting light emitted from the outside by a light reflecting surface and receiving the light is disclosed.
Japanese Utility Model Publication No. 56-120901 Japanese Patent Publication No. 7-71886 JP-A-11-170819

  However, in the conventional technique shown in Patent Document 1, there are cases where the appearance of the tire is impaired, and the road surface is damaged when the tire is worn to embed the bow, or the damage to the tire is accelerated.

  In the prior art disclosed in Patent Document 2, it is necessary to greatly change the structure and members of the tire, and it is difficult to easily penetrate the consumer.

  Further, in the prior art disclosed in Patent Document 3, since the reflected light is detected to check the degree of wear, the reflected light is detected even if the reflecting surface is exposed when the reflecting surface is dirty or the light receiving surface is dirty. In some cases, this may not be recognized even if the tire exceeds the wear limit.

  Accordingly, in view of the above problems, the present invention provides a tire wear detection system and a pneumatic tire that can easily deal with existing tires without damaging the tire and road surface and have high reliability for tire wear detection. For the purpose.

  The first feature of the present invention is that a strain sensor that detects strain applied to a protrusion disposed in a groove portion of a tread portion of a pneumatic tire and a difference between a maximum value and a minimum value of a waveform transmitted from the strain sensor. Is a tire wear detection system including detection means for detecting that a predetermined threshold value determined by the tire size has been exceeded.

  According to the tire wear detection system according to the first feature, since the strain applied to the protruding portion is detected, highly reliable wear detection can be performed. Further, since the tire surface is not processed, the tire and the road surface are not damaged. Furthermore, since only the protrusion and the strain sensor need be provided, it is possible to easily deal with existing tires.

  In addition, the tire wear detection system according to the first feature may further include notification means for notifying a detection result by the detection means. According to this tire wear detection system, it can be easily recognized that tire wear has occurred.

  A second feature of the present invention is a pneumatic tire including a protrusion disposed in a groove portion of a tread portion, and a strain sensor disposed on the inner side of the protrusion in the tire radial direction and detecting strain applied to the protrusion. It is a summary.

  According to the pneumatic tire according to the second feature, since the strain applied to the protrusion is detected, highly reliable wear detection can be performed. Further, since the tire surface is not processed, the tire and the road surface are not damaged. Furthermore, since it is only necessary to provide a protrusion and a strain sensor, it is possible to easily deal with existing tires.

  In addition, a plurality of protrusions of the pneumatic tire according to the second feature may be provided, and the plurality of protrusions may have different heights in the tire radial direction. According to this pneumatic tire, wear can be detected step by step at a plurality of heights, so wear detection with higher reliability can be performed.

  Further, the protrusions of the pneumatic tire according to the second feature may be continuously arranged in the tire circumferential direction. According to this pneumatic tire, the strain sensor may be disposed anywhere, and it is not necessary to strictly align the strain sensor and the protrusion.

  ADVANTAGE OF THE INVENTION According to this invention, a tire wear detection system and a pneumatic tire which can respond easily to an existing tire without damaging a tire or a road surface and have high reliability for tire wear detection can be provided.

  Next, the present invention will be described in detail.

(Pneumatic tire)
First, an embodiment of a pneumatic tire according to the present invention will be described with reference to FIGS. 1 and 2.

  As shown in FIG. 1, a tread pattern including a convex portion 20 and a groove portion 30 is formed on the surface of the tread portion of the pneumatic tire 10. Protrusions 40 are disposed in the groove 30 at regular intervals.

  Since the protrusion 40 is preferably the same height as the slip sign, it has a height of 1.6 mm from the bottom of the groove. The protrusion 40 is made of a tread rubber, and is integrally molded as a tread pattern together with the protrusion 20 and the groove 30 in the vulcanization process.

  In the pneumatic tire according to the present embodiment, as shown in FIG. 2A, the convex surface 21 comes into contact with the road surface 100 and rolls. A protrusion 40 is disposed on the groove surface 31, and a carcass 50 that functions as a strength member for maintaining the pressure of air filled in the tire is provided on the inner side in the tire radial direction of the tread portion, and a rubber layer inside the tire. An inner liner 60 or the like is configured. The other structures are conventionally known structures and are not particularly limited.

  A strain sensor 70 is disposed on the inner side in the tire radial direction of the inner liner 60 corresponding to the back side of the protrusion 40. The strain sensor 70 detects vibration and displacement of the protrusion 40.

  When the tire is worn, the projection 40 contacts the road surface 100 as shown in FIG. At this time, the strain sensor 70 detects a large strain (displacement) as compared with the state of FIG.

  A method for determining that the tire is worn will be described in detail later.

(Tire wear detection system)
As shown in FIG. 3, the tire wear detection system according to the present embodiment is mounted on one automobile, and includes strain sensors 70 a, 70 b, 70 c, 70 d, an ECU (detection means) 80, a meter display unit 90 ( Notification means).

  The strain sensors 70a, 70b, 70c, and 70d detect strain applied to the protrusions 40 disposed in the grooves of the tread portion of the pneumatic tire, and are disposed in each tire of the automobile. In FIG. 4, one strain sensor is provided for each tire, but it goes without saying that a plurality of strain sensors may be provided for one tire. Further, the strain sensors 70a, 70b, 70c, and 70d output signals including detected values to the ECU 80.

  The ECU (Electronic Control Unit or Engine Control Unit) 80 is a predetermined threshold that is determined by the tire size so that the difference between the maximum value and the minimum value of the waveforms transmitted from the strain sensors 70a, 70b, 70c, 70d is determined. Detects that it exceeds Here, normally, in the rolling tire, when the protrusion 40 is located on the road surface 100 side, the waveform shows the maximum value, and when the protrusion 40 is located on the vehicle body side, the waveform shows the minimum value. The ECU 80 controls each part of the automobile, such as determining the fuel injection amount and injection time of the engine based on information from each sensor (instrument).

  Specifically, the ECU 80 receives waveform data indicating the amount of distortion output from the strain sensors 70a, 70b, 70c, and 70d as shown in FIG. 4, and records this waveform data in the storage device. The storage device may be an internal storage device such as a RAM or an external storage device such as an HD. Even with normal tires with little wear, the ECU 80 records this waveform because it can detect strain each time it comes in contact with the ground. Further, as wear progresses, distortion increases and fine irregularities on the road surface are picked up, and changes occur from the waveform data recorded in the storage device. The ECU 80 detects that the difference between the maximum value and the minimum value of the waveform data (A in FIG. 4) exceeds a predetermined threshold determined by the tire size. It is assumed that the threshold value is stored in the ECU 80 in advance by the tire manufacturer for each tire.

  Output signals from the strain sensors 70a, 70b, 70c, and 70d to the ECU 80 may be transmitted by wire or wirelessly using a wireless LAN or the like.

  The meter display part 90 notifies by displaying the detection result by ECU80 so that visual recognition is possible. The meter display unit 90 displays a speedometer, a gasoline remaining amount, and the like, and also displays that the wear has been detected by the ECU 80. In FIG. 3, the position of the tire where wear has been detected is lit.

  In addition, the part which displays that abrasion was detected is not restricted to the meter display part 90, You may provide a different display apparatus separately. Further, instead of displaying, it may be notified that wear has been detected by sound, such as sounding an alarm when wear is detected.

(Modification)
2 shows that one protrusion 40 is provided, but as shown in FIG. 5, a plurality of protrusions 40a and 40b are provided, and a plurality of corresponding strain sensors 70e and 70f are also provided. May be. Moreover, it is preferable that the heights in the tire radial direction of the plurality of protrusions 40a and 40b are different from each other.

  Since the heights of the plurality of protrusions 40a and 40b are different, the waveform data of the strain detected by the strain sensors 70e and 70f is different. The ECU 80 receives different waveform data from the plurality of strain sensors 70e and 70f and detects them in stages. That is, when a waveform exceeding a predetermined threshold value is received from the strain sensor 70f that detects the strain of the projection 40b having a high height, it is displayed on the meter display unit 90 that the wear is mild. On the other hand, when a waveform exceeding a predetermined threshold is received from the strain sensor 70e that detects the strain of the projection 40a having a low height, it is displayed on the meter display unit 90 that the wear is severe.

  Moreover, as shown in FIG. 6, the protrusion part 40c may be continuously arrange | positioned in the tire circumferential direction. At this time, the strain sensor 70c may be disposed at any location on the inner side in the tire radial direction.

(Action and effect)
According to the pneumatic tire 10 and the tire wear detection system according to the present embodiment, since the distortion applied to the protrusion 40 is detected, highly reliable wear detection can be performed. Further, since the tire surface is not processed, the tire and the road surface are not damaged. Furthermore, since only the protrusion 40 and the strain sensor 70 need be disposed, it is possible to easily deal with existing tires.

  Further, according to the wear detection system according to the present embodiment, it is possible to notify that the wear of the tire is progressing by displaying on the meter display unit 90 or the like. For this reason, it is possible to easily and instantly recognize that tire wear has occurred on the driver or the like.

  Further, as shown in FIG. 5, a plurality of protrusions 40 a and 40 b of the pneumatic tire 10 are provided, and the plurality of protrusions 40 a and 40 b may have different heights in the tire radial direction. For this reason, wear can be detected step by step at a plurality of heights, and wear detection with higher reliability can be performed.

  Moreover, as shown in FIG. 6, the protrusion part 40c of the pneumatic tire 10 may be continuously arrange | positioned in the tire circumferential direction. With such a configuration, since the strain sensor 70g may be disposed anywhere, it is not necessary to strictly align the strain sensor 70g and the protrusion 40c.

It is a perspective view of the pneumatic tire concerning this embodiment. It is sectional drawing along the tire rotating shaft of the pneumatic tire which concerns on this embodiment. It is a figure explaining the tire wear detection system concerning this embodiment. It is an example of the waveform data which the tire wear detection system concerning this embodiment receives. It is sectional drawing along the tire rotating shaft of the pneumatic tire which concerns on a modification (the 1). It is sectional drawing along the tire rotating shaft of the pneumatic tire which concerns on a modification (the 2).

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Pneumatic tire 20 ... Convex part 21 ... Convex part surface 30 ... Groove part 31 ... Groove part surface 40, 40a-40c ... Protrusion part 50 ... Carcass 60 ... Inner liner 70, 70a-70e ... Strain sensor 80 ... ECU
90 ... Meter display unit 100 ... Road surface

Claims (5)

A strain sensor that detects strain applied to the protrusion disposed in the groove portion of the tread portion of the pneumatic tire;
A tire wear detection system comprising: detecting means for detecting that a difference between a maximum value and a minimum value of a waveform transmitted from the strain sensor exceeds a predetermined threshold determined by a tire size.   The tire wear detection system according to claim 1, further comprising notification means for notifying a detection result by the detection means. A protrusion disposed in the groove portion of the tread portion;
A pneumatic tire, comprising: a strain sensor that is disposed on an inner side in a tire radial direction of the protrusion, and detects a strain applied to the protrusion.   The pneumatic tire according to claim 3, wherein a plurality of the protrusions are provided, and the plurality of protrusions have different radial heights. The pneumatic tire according to claim 3, wherein the protrusions are continuously arranged in the tire circumferential direction.

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