阅读说明：本技术 具有无线指示器的轮胎 (Tyre with wireless indicator ) 是由 J.奥加拉 J.赖赛宁 T.索伊尼 P.伊索-克托拉 S.瓦帕科斯基 T.泰佩尔 于 2018-06-27 设计创作，主要内容包括：一种构造成围绕旋转轴线(AXR)旋转的轮胎(100),轮胎(100)包括形成轮胎(100)的胎面(120)的至少部分的胎面块(110)和包括初级电容构件(210)和初级电感构件(220)的电路(200),其中初级电容构件(210)的至少部分布置成与胎面(120)相距第一距离(d1)并在胎面块(110)的内部,并且初级电感构件(220)的至少部分布置成朝向轮胎(100)的内部而距胎面(120)第二距离(d2)。轮胎进一步包括询问器(300),其包括电源(330)、通信电路(310)和次级电感构件(320)。次级电感构件(320)与初级电感构件(310)布置在胎面(120)的同一侧上,并且次级电感构件(320)的至少部分布置成与胎面(120)相距第三距离(d3),第三距离(d3)大于第二距离(d2)。一种用于将磨损指示器(190)布置到轮胎(100)的方法。(A tire (100) configured to rotate about an axis of rotation (AXR), the tire (100) comprising a tread block (110) forming at least part of a tread (120) of the tire (100) and a circuit (200) comprising a primary capacitive member (210) and a primary inductive member (220), wherein at least part of the primary capacitive member (210) is arranged at a first distance (d1) from the tread (120) and inside the tread block (110) and at least part of the primary inductive member (220) is arranged at a second distance (d2) from the tread (120) towards the inside of the tire (100). The tire further includes an interrogator (300) including a power source (330), a communication circuit (310), and a secondary inductive member (320). The secondary inductive member (320) is arranged on the same side of the tread (120) as the primary inductive member (310), and at least part of the secondary inductive member (320) is arranged at a third distance (d3) from the tread (120), the third distance (d3) being greater than the second distance (d 2). A method for arranging a wear indicator (190) to a tire (100).)

1. A tire (100) configured to rotate about an axis of rotation (AXR), the tire (100) comprising

-a tread block (110) forming at least part of a tread (120) of the tyre (100),

-a circuit (200) comprising

A primary capacitive member (210), wherein at least part of the primary capacitive member (210) is arranged at a first distance (d1) from the tread (120) and inside the tread block (110), and

a primary inductive member (220) arranged at least partially at a second distance (d2) from the tread (120) towards the interior of the tyre (100), and

an interrogator (300) comprising

A power source (330),

a communication circuit (310), and

a secondary inductance component (320), wherein

-the secondary inductive member (320) is arranged on the same side of the tread (120) as the primary inductive member (310), and

-at least part of the secondary inductance means (320) is arranged at a third distance (d3) from the tread (120), the third distance (d3) being greater than the second distance (d 2).

2. The tyre (100) of claim 1,

-the primary capacitive member (210) is configured to wear when the tread (120) is worn, and

-the second distance (d2) is greater than the first distance (d1), whereby

-at least part of the primary capacitive member (210) is configured to wear out before the primary inductive member (220).

3. Tyre (100) according to claim 1 or 2,

-the interrogator (300) is arranged on a surface (130) of the tyre (100) or at least partially in the tyre (100);

preferably, the first and second electrodes are formed of a metal,

-said interrogator (300) is arranged on a surface (130) of a cavity confined by said tyre (100);

more preferably still, the first and second liquid crystal compositions are,

-said tyre (100) is a pneumatic tyre, and

-said interrogator (300) is arranged on an inner surface (130) of said pneumatic tyre (100).

4. Tyre (100) according to any one of claims 1 to 3,

-the primary inductive means (220) is configured to form a primary magnetic field (B1), the primary magnetic field (B1) pointing in a primary direction (dB1) at the center of the primary inductive means (220), and

-the secondary inductive means (320) is configured to form a secondary magnetic field (B2), the secondary magnetic field (B2) pointing in a secondary direction (dB2) at the center of the secondary inductive means (320), wherein

-an angle (β) between the primary direction (dB1) and a normal (N1) to the tread (120) is less than 30 degrees or greater than 150 degrees;

preferably

-an angle (α) between the primary direction (dB1) and the secondary direction (dB2) is smaller than 30 degrees or larger than 150 degrees.

5. Tyre (100) according to any one of claims 1 to 4,

-the primary inductive means (220) comprises a primary coil (222), the primary coil (222) being configured to form a primary magnetic field (B1), the primary magnetic field (B1) pointing in a primary direction (dB1) at the center of the primary coil (222), the primary coil (222) having a primary cross-section (XS1) in a plane having a normal parallel to the primary direction (dB1), and

-the secondary inductive means (320) comprises a secondary coil (322), the secondary coil (322) being configured to form a secondary magnetic field (B2), the secondary magnetic field (B2) pointing in a secondary direction (dB2) at the center of the secondary coil (322), the secondary coil (322) having a secondary cross-section (XS2) in a plane having a normal parallel to the secondary direction (dB2), wherein

-the primary cross section (XS1) and the secondary cross section (XS2) are arranged with respect to each other such that an imaginary straight line (IML) parallel to a primary axis (AX1) and/or a secondary axis (AX2) penetrates both the primary cross section (XS1) and the secondary cross section (XS 2);

preferably, the first and second electrodes are formed of a metal,

-the area (Axs12) of the overlapping portion (XS12) of the primary cross section (XS1) and the secondary cross section (XS2) is at least 25% of the smaller of: an area (Axs1) of the primary cross-section (XS1) and an area (Axs2) of the secondary cross-section (XS 2).

6. Tyre (100) according to any one of claims 1 to 5,

-a distance (d12) between the primary inductive member (220) and the secondary inductive member (320) is at most 75 mm.

7. Tyre (100) according to any one of claims 1 to 6,

[A]

-the primary inductive component (220) comprises a primary coil (222) and at least one of:

a primary core (224) in magnetic connection with the primary coil (222), or

A primary plate (225) in magnetic connection with the primary coil (222), and

-the primary core (224) or the primary plate (225) comprises a paramagnetic or ferromagnetic material; and/or

[B]

-the secondary inductive means (320) comprises a secondary coil (322) and at least one of:

a secondary core (324) in magnetic connection with the secondary coil (322), or

A secondary plate (325) in magnetic connection with the secondary coil (322), and

-the secondary core (324) or the primary plate (325) comprises a paramagnetic or ferromagnetic material.

8. Tyre (100) according to any one of claims 1 to 7, wherein said interrogator (300) is configured to measure at least one of:

-mutual inductance of the secondary capacitive member (320) and the circuit (200),

-an inductance of the circuit (200), and

-a frequency of oscillation of the circuit (200).

9. Tyre (100) according to any one of claims 1 to 8,

the circuit 200 is passive in terms of energy.

10. Tyre (100) according to any one of claims 1 to 9,

-the tread block (110) comprises a first material, such as rubber,

-the tread block (110) delimits a blind hole for the electric circuit (200),

-the primary capacitive member (210) comprises a capacitor (210)₁, 210₂, 210₃, 210₄, 210₅, 210₆212,214) and a dielectric material (213) such that

-at least some of the dielectric material (213) remaining with the capacitor (210) and the portion of the tread block (110) in a direction perpendicular to the normal (N1) of the tread (120)₁, 210₂, 210₃, 210₄, 210₅, 210₆212, 214);

-preferably

-the dielectric material (213) is not the same material as the first material.

11. Tyre (100) according to any one of claims 1 to 10, wherein said tyre (100) comprises

-a reinforcing band (150), such as a steel band (150), and

-a portion of the stiffening band (150) is arranged intermediate the primary inductive member (220) and the secondary inductive member (320);

preferably, said tyre (100) further comprises

-one layer (155) or a plurality of layers (155) comprising fibrous material.

12. Tyre (100) according to any one of claims 1 to 11,

-the interrogator (300) comprises a secondary sensor assembly (340) in addition to the secondary inductive member (320);

preferably, the first and second electrodes are formed of a metal,

-the secondary sensor assembly (340) comprises at least one of:

the pressure sensor is arranged on the base plate,

an acceleration sensor for detecting the acceleration of the vehicle,

a temperature sensor;

preferably, the first and second electrodes are formed of a metal,

-the secondary sensor assembly (340) comprises a pressure sensor and an acceleration sensor.

13. Tyre (100) according to any one of claims 1 to 12, wherein said primary capacitive member (210) is configured such that

-for a first wear value (w1), the derivative of the capacitance (c1) of the primary capacitive member (210) with respect to wear (w) has a first capacitance change value (dc1/dw | w1),

-for a second wear value (w2), the derivative of the capacitance (c1) of the primary capacitive member (210) with respect to wear (w) has a second capacitance change value (dc1/dw | w2), wherein

-the first capacitance change value (dc1/dw | w1) is different from the second capacitance change value (dc1/dw | w 2);

preferably, the first and second electrodes are formed of a metal,

-the first wear value (w1) is smaller than the second wear value (w2), and

-the absolute value of the first capacitance change value (dc1/dw | w1) is larger than the absolute value of the second capacitance change value (dc1/dw | w 2).

14. A method for arranging a wear indicator (190) to a tread block (110) of a tire (100), the tread block (110) forming part of a tread (120) of the tire (100), the method comprising

-arranging available

A circuit (200) comprising a primary capacitive component (210) and a primary inductive component (220), and

an interrogator (300) comprising a power source (330), a communication circuit (310), and a secondary inductive member (320), the method comprising

-arranging at least part of the electrical circuit (200) into the tread block (110), and

-attaching the interrogator (300) on a surface (130) of a cavity confined by the tyre (100) or at least partially into the tyre (100) such that

-at least part of the secondary inductive means (320) is arranged further from the tread (120) than part of the primary inductive means (220).

15. The method of claim 14,

[A]

-said primary capacitive member (210) is configured to wear in use of said tyre (100), said method comprising

-arranging at least part of the primary capacitive member (210) of the circuit (200) into the tread block (110), and

-arranging the primary inductive member (220) into the tyre (100) such that at least part of the primary capacitive member (210) is closer to the tread (120) than at least part of the primary inductive member (220), and/or

[B]

-the method comprises arranging a blind hole (112) to the tread block (110), and

-arranging at least part of the electrical circuit (200) into the blind hole (112).

Technical Field

The present invention relates to a tire having an electrical wear indicator. The present invention relates to a tire having a wear indicator based on an LC or LCR resonator, the inductance and/or oscillation frequency of the LC or LCR resonator being configured to change as the surface of the tire wears.

Background

Remote monitoring systems using LCR (inductance-capacitance-resistance) circuits are known, for example, from document US 2005/0007239. In conjunction with an interrogation device, such circuitry enables monitoring of a variety of properties, including strain, temperature, pressure, identification, performance, chemical phase changes (such as melt and solidification states), fluid level, wear, rotation rate, orientation, and proximity. In general, even though inductors themselves are used to generate electricity through a changing magnetic field, LCR circuits are passive, e.g., there is no power source to convert chemical energy into electricity. However, the interrogation device is active, including a power source that converts chemical energy into electricity. Typically, the interrogation device is a handheld device or a device secured to the system. The position of the interrogation device relative to the circuit is reasonably freely selectable. However, the power consumption of the interrogation device depends on the read distance.

Disclosure of Invention

Such remote monitoring systems have been found to be particularly feasible when the measured surface (such as the wear surface of a tyre) needs to be leak-proof against water and/or other liquids or air and/or other gases. These problems are even more important if the liquid or gas is pressurized. In such a case, the wiring from the measurement circuit will easily cause a leakage problem. However, there is no such problem in the wireless remote monitoring system.

There are problems when a system with an interrogator and circuitry is used to measure at least a property of a surface, such as wear of the tread of a tire. For example, in such measurements, the coils are embedded in a block of worn material (e.g., a tread block of a tire). This affects the sensitivity of the measurement. It has been noted that sensitivity can be improved by applying the interrogation device to the appropriate location. The interrogator is applied to the appropriate location relative to the circuitry and device (i.e., the tire) from which a property such as wear is measured. In some applications, the device (i.e., the tire) naturally includes some metal intermediate the circuit and the interrogator. In such a system, the structure of the device degrades the intermediate wireless communication. In particular, in such cases the mutual position between the circuit and the interrogator becomes important. In this description, the device is a tire with an electrical wear indicator. The tire may be a pneumatic tire. A tire or pneumatic tire typically includes a metal reinforcing band, such as a steel band. The metal strip may interfere with RF communication between the interrogator and the circuitry.

Drawings

Figure 1a shows the wear indicator 190 as a side view,

fig. 1b and 1c show the device 100 as a side view with a wear indicator 190, the wear indicator 190 being used to measure the wear of the surface 120 of the device 100,

FIG. 1d shows the wear of the wear indicator of FIG. 1a (w, w1, w2),

FIG. 1e shows the worn wear indicator of FIG. 1c, wherein the indicator has worn down to the wear of the surface 120 (w, w1, w2),

figure 1f shows a wear indicator 190 with two ferrite plates as a side view,

fig. 1g shows the wear indicator as a side view, with the capacitive member comprising a plurality of capacitors,

figures 2a to 2e show embodiments of a wear indicator and corresponding device,

figure 3 shows the capacitance c1 of the primary capacitive member 210 as a function of wear w for some embodiments,

figure 4a indicates the direction of the magnetic field generated and/or received by the primary inductive component 220 and the secondary inductive component 320,

figures 4b and 4c indicate the magnetic fields generated and/or received by the primary inductive member 220 and the secondary inductive member 320 when at least the reinforcing structures 150,155 are arranged in the main body 110,

figures 5a and 5b indicate the positioning of the primary inductive member 220 relative to the secondary inductive member 320,

figures 6a to 6i show an embodiment of the primary capacitive member 210,

figure 7 shows a system comprising a wear indicator, a gateway device 400 and a cloud server 500,

FIGS. 8a and 8b show a primary capacitive member 210 disposed in a blind hole 112 of a tire tread 120, an

Fig. 9a and 9b show a pneumatic tire 100 with a wear indicator.

Detailed Description

In the following, embodiments are explained in connection with a wear indicator. However, in this description, the wear indicator is used for the purpose of the more general example of the device 100, and in particular the tire 100 (such as a pneumatic tire) with the embedded circuit 200 and interrogator 300. Fig. 1a shows a wear indicator 190 in a front view. The wear indicator includes a circuit 200 and an interrogator 300. Interrogator 300 is configured to wirelessly interact with circuitry 200, as described in detail below. This contributes to the leakage problem indicated above.

The wear indicator 190 is arranged in the tire 100 such that when the tread 120 of the tire is worn, the capacitive components of the wear indicator 190 are also worn. The tire may be a pneumatic tire. However, the tire may be a non-pneumatic tire. Typically, both pneumatic and non-pneumatic tires define a chamber (e.g., a single chamber for pressurized air) or multiple chambers (chambers within the non-pneumatic tire). The tire may be a tire for a passenger vehicle, such as a passenger car tire. The tire may be a heavy tire, i.e., a tire for heavy machinery such as a conveyor, loader, truck, crawler. The tire may be a tire for a motorcycle.

The circuit 200 includes a primary capacitive component 210 and a primary inductive component 220. The primary capacitive member 210 is electrically connected to the primary inductive member, thereby forming an electrical oscillator. The circuit 200 may further include a resistive member (not shown). Thus, the oscillator is an LC or LRC oscillator. The circuit 200 is passive in energy, i.e., the circuit 200 is not configured as a battery to convert chemical energy into electricity. As is known per se from LC or LCR oscillators, the primary inductive component 220 converts magnetic energy into electricity, which becomes temporarily stored in the primary capacitive component 210. The oscillation frequency and/or inductance of the circuit 200 depends on the capacitance of the primary capacitive component 210 and the inductance of the primary inductive component 220. Typically, the angular resonance frequency of the circuit is expressed asWhere L1 is the inductance of primary inductive means 220 and c1 is the capacitance of primary capacitive means 210. As will be detailed below, in an embodiment, the primary capacitive member 210 is configured to wear in use, whereby its capacitance c1 varies. This may affect, for example, the angular resonance frequency ω. This also affects the mutual inductance (particularly at a certain frequency) of the primary inductive component 220 and the secondary inductive component 320. In this way, for example, these quantities indicate how much the primary inductive component 220 has worn. However, other quantities may also affect the capacitance c1 of the primary capacitive member 210. Thus, for example, the aforementioned amount may also be indicative of other parameters of the primary capacitive member 210 or the environment in the vicinity of the primary capacitive member 210, such as moisture in the vicinity of the primary capacitive member 210 and/or moisture, for example, in the middle of the two electrodes (212, 214) of the primary capacitive member 210.

The primary capacitive member 210 does not need to wear during measurement. For example, it is possible to measure the humidity of the environment in which the circuit is embedded. As is known, humidity affects the dielectric constant of the capacitor and therefore also the angular resonance frequency ω of the LC circuit. Additionally or alternatively, the inductance of the primary inductive means 220 may be influenced by the use and/or environment of the apparatus 100. For example, if the body 110 of the device 100 includes a magnetic material, the inductance of the primary inductive member 220 may change as the material of the body 110 wears. Additionally or alternatively, the circuit 240 may include a primary sensor assembly 240 for measuring some quantity.

Interrogator 300 includes power source 330, communication circuit 310, and secondary inductive member 320. A power source is required to power the interrogator. The power source may, for example, be configured to convert mechanical and/or chemical energy into electrical energy. Alternatively or additionally, the power source may include a component configured to convert magnetic energy into electricity. Alternatively or additionally, the power source may include a high capacitance capacitor (e.g., a supercapacitor) that stores electrical energy as such. Such high capacitance capacitors may be charged inductively or mechanically, for example, with a means of converting magnetic or mechanical energy into electricity, respectively. A high capacitance capacitor herein refers to a capacitor having a DC capacitance of at least 1 muf.

The secondary inductive member 320 is used to interrogate the circuit 200. Thus, by creating a magnetic field for secondary inductive member 320, the magnetic field also penetrates primary inductive member 220, thus affecting the mutual inductance of interrogator 300 and circuit 200. In this way, the mutual inductance and/or angular resonance frequency (or resonant frequency) of the circuit may be measured.

The communication circuit 310 may be used to transmit the measured data to the gateway device 400 (see fig. 7). The communication circuit may include a control circuit for measuring the mutual inductance and/or resonant frequency of the circuit. In the alternative, interrogator 300 may include a separate control circuit for this purpose. In an embodiment, interrogator 300 is configured to measure at least one of: [i] the mutual inductance of the secondary capacitive member 320 and the circuit 200, [ ii ] the inductance of the circuit 200, and [ iii ] the resonant frequency of oscillation of the circuit 200.

Referring to fig. 1b, such a wear indicator 190 may be used to measure wear of the first surface 120 of the body 110, in particular wear of the tire tread 120, portions of the tire tread 120 being formed by tread blocks 110. The first surface 120 is a surface that wears away in use. When such a wear indicator 190 is used, the circuit 200 is applied to the wear surface 120 (e.g., the tread of a tire) such that when the wear surface 120 wears, the primary capacitive member 210 also wears. The capacitor need not touch the surface of an unworn wear surface, as it may be sufficient to measure the wear of only a reasonable amount of such a surface that has worn. However, preferably, only the primary capacitive member 210 wears, while the primary inductive member 220 does not. Thus, and referring to fig. 1c, in an embodiment, the circuit 200 is arranged in the body 110 such that the primary capacitive member 210 is configured to wear when the first surface 120 of the body 100 wears. Further, at least a portion of the primary capacitive member 210 is disposed a first distance d1 from the first surface of the body and inside the body 110. Further, at least a portion of the primary inductance member 220 is disposed at a second distance d2 from the first surface 120 of the body 110 and inside the body 110. In the wear indicator, the second distance d2 is preferably greater than the first distance d 1. In this way, as the first surface 120 wears, the primary capacitive member 210 begins to wear before the primary inductive member 220 begins to wear. Preferably, the wear indicator 190 is arranged such that the primary inductive member 220 does not wear in normal use. Furthermore, as indicated above, in some other embodiments, the second distance d2 may be less than the first distance d1 because neither the primary capacitive member nor the primary inductive member need to wear out.

Furthermore, interrogator 300 is arranged relative to circuit 200 such that secondary inductive member 320 is arranged on the same side of first surface 120 as primary inductive member 220. The secondary inductance member 320 may be disposed inside the body 110 or on the other side of the body 110. Further, at least a portion of the secondary inductance member 320 is disposed a third distance d3 from the first surface 120 of the body, the third distance d3 being greater than the second distance d 2. This has the following effect: until the primary inductive member 220 begins to wear (if it were to wear), the secondary inductive member 320 also does not begin to wear. This has the additional effect of: such placement improves the magnetic coupling between the primary inductive member 220 and the secondary inductive member 320.

Herein, the body 110 and the wear indicator 190 are combined to form a tire 100 according to various embodiments. Referring to fig. 9a and 9b, in some embodiments, the body 110 is a body portion of a pneumatic tire, whereby the device 100 is a pneumatic tire with an integrated electrical wear indicator. The body 110 may be, for example, a tread block of the tire 100.

Referring to fig. 1d, in general, the amount of wear is denoted by the symbol w. Fig. 1d indicates two wear values w1 and w 2. In fig. 1d, the wear value w1 refers to the wear value w1 of the surface 120 of fig. 1 d. The surface 120 may be, for example, unworn, and the wear value w1 may be, for example, zero.

FIG. 1e shows the device 100 of FIG. 1d after the surface 120 has worn a certain amount. The wear value of fig. 1e corresponds to w 2. Thus, in the middle of FIG. 1d and FIG. 1e, the surface 120 has worn an amount w2-w 1.

Referring to FIG. 1b, in an embodiment, interrogator 300 is disposed on second surface 130 of object 110, where second surface 130 is opposite first surface 120. The second surface may be a surface of a cavity bounded by the tire 100. For example, the second surface 130 may be a surface of the interior of the pneumatic tire 100.

Because the primary capacitive member 210 is configured to wear the same amount as the wear surface 120, preferably, the primary capacitive member 210 is at most as resistant to wear to the same extent as the body 110. In other words, preferably, the material of the primary capacitive member 210 is at most resistant to wear to the same extent as the material of the body 110. This ensures that the primary capacitive member 210 wears the same amount in use as the wear surface 120; at least when the surface 120 has worn to the limit where the primary capacitive member 210 begins to wear (see fig. 2 a).

Fig. 2a to 2e indicate some embodiments of the device 100. In these figures, the primary capacitive member 210 includes a first electrode 212 and a second electrode 214.

As seen in fig. 2a, in an embodiment, the primary capacitive member 210 is arranged at a distance from the first surface 120 when the first surface 120 is unworn. In this way, the wear indicator is configured not to measure small wear values, but only values greater than a limit. Such a limit is defined by the distance between the primary capacitive member 210 and the surface 120.

In the embodiment of figure 2b of the drawings,the primary capacitive member 210 includes a base capacitor 216. The base capacitor 216 is configured to not wear in use. This has the following effect: the capacitance of the primary capacitive member 210 remains sufficiently high throughout the design life of the wear indicator. The base capacitor 216 may comprise portions of electrodes (212, 214; see fig. 6b and 6 d). Additionally or alternatively, the base capacitor 216 may comprise a separate electrode (see fig. 6 f). Additionally or alternatively, the base capacitor 216 may comprise a separate capacitive component (see fig. 6 g). As indicated in FIG. 1g, when the primary capacitive member 210 comprises a discrete capacitor 210₁、210₂、210₃、210₄、210₅And 210₆When used, a separate capacitive member may also be used.

The purpose of such a base capacitor 216 is to adjust the capacitance c1 and thus also the angular resonance frequency ω of the circuit 200. This may improve the sensitivity of the circuit 200. In particular, this may improve the sensitivity of paired circuit 200 and interrogator 300, as the measurement electronics of interrogator 300 may be designed to operate most efficiently over a defined frequency range. However, if the interrogator design is different, this problem does not necessitate the use of the base capacitor 216.

In an embodiment, the base capacitor 216 (or 210)₆) Forming at least 25% of the capacitance c1 of the primary capacitive member 210. For example, the base capacitor 216 may be disposed deeper (i.e., farther from the surface 120) in the body 110 than the worn portion of the primary capacitive member 210. For example, the base capacitor 216 may be disposed on the other side 130 of the body 110, for example, as compared to a worn portion of the primary capacitive member 210.

As indicated in FIG. 1g, when the primary capacitive member 210 comprises a plurality of capacitors 210₁、210₂、210₃、210₄、210₅And 210₆The member 210 placed furthest from the surface 120₆May be used as a base capacitor 216 that is not designed to wear in use. However, in the embodiment according to fig. 1g, the capacitor 210₆And may also be designed to wear in use.

In the embodiment of FIG. 2c, the components of interrogator 300 are disposed within body 110. In the embodiment of fig. 2d, the first electrode 212 and the second electrode 214 are wider at the wear surface 120 than at deeper locations inside the body. Such electrodes are shown in more detail, for example, in fig. 6c and 6 d. In the embodiment of fig. 2e, interrogator 300 includes secondary sensor assembly 340 in addition to secondary inductive member 320. Such secondary sensor assembly 340 may include one or more sensors configured to measure the environment in which interrogator 300 is located. The secondary sensor assembly 340 may include, for example, at least one of a temperature sensor, a pressure sensor, and an acceleration sensor.

Referring to fig. 2d, the circuit 200 may also include a primary sensor assembly 240. The primary sensor assembly may include one or more sensors that require only little electricity to function. The primary sensor assembly may include, for example, at least one of a pressure sensor, a humidity sensor, and a temperature sensor.

It has been observed that as the primary capacitive member 210 wears, the effect of the change in capacitance for small wear values may be difficult to detect. The inventors believe that this is a result of a proportional change in capacitance (a change proportional to the capacitance of the member 210) which may initially be smaller than later because the capacitance value is also smaller later. This problem can be corrected to some extent using the base capacitor as discussed above. Preferably, however, this problem is also corrected by careful design of the primary capacitive member 210. Without detailing the structure of the components at this point, fig. 3 shows the capacitance value c1 as a function of wear w for four different primary capacitive components 210.

As shown by curve 810 in fig. 3, in an embodiment, the capacitance c1 of the primary capacitive member 210 may decrease with a constant slope for all wear values w. Such a curve may be the result of an electrode in the form of a parallel plate (fig. 6a) or a concentric electrode (fig. 6e) with or without a base capacitor 216 (see also fig. 6b and 6 f). It is also possible to use a separate capacitor 210 as indicated in fig. 1g₁、210₂、210₃、210₄And 210₅(capacitor 210)₆Is a basic capacitor) to achieve correspondenceThe effect is that the capacitors are equally spaced and equally large in capacitance. However, since the capacitance c1 also decreases for small wear values, the primary capacitive member is arranged to touch the wear surface 120 as in fig. 1b, 1g, 2b, 2d and 2 e.

As shown by curve 820 in fig. 3, in an embodiment, the capacitance c1 of the primary capacitive member 210 may decrease at a constant slope only for reasonably large wear values w. Since the capacitance c1 is not initially reduced, the primary capacitive member is arranged at a distance from the wear surface 120 as in fig. 2a and 2 c. Such a curve may be the result of an electrode in the form of a parallel plate (fig. 6a) or a concentric electrode (fig. 6e) with or without the base capacitor 216 (see also fig. 6b and 6f), since the slope is constant thereafter.

As shown by curve 830 in fig. 3, in an embodiment, the capacitance c1 of the primary capacitive member 210 may decrease such that the capacitance c1 initially changes more rapidly than later as a function of wear. Formally, the capacitance c1 of the primary capacitive member 210 is a function of wear c1= c1 (w). Further, the rate of change of capacitance is the derivative dc1/dw of the capacitance c1 with respect to wear w. For a certain wear value w1, the derivative dc1/dw at this point is represented herein and generally by dc1/w | w 1. As is well known, the derivative is the slope of the tangent at that point. The corresponding tangent to curve 830 is depicted in the figure by line 831. For another wear value w2, the derivative dc1/dw at this point is represented herein and generally by dc1/w | w 2. The corresponding tangent to curve 830 is depicted in the figure by line 832. As indicated in the figure, the derivative is negative because the capacitance decreases as the surface wears.

As shown by curve 830 in fig. 3, in an embodiment, the absolute value of the derivative for small wear values w is greater than the absolute value of the derivative for large wear values w. Formally, when w2>W1, | dc1/w | w1| | non-conducting>I | dc1/w | w2 |. In this context, | dc1/w | w1| | represents the absolute value of dc1/w | w1, and | | | dc1/w | w2| | represents the absolute value of dc1/w | w 2. As is known, the capacitance is proportional to the area of the electrodes and inversely proportional to the distance between the electrodes. Thus, curve 830 may be the result of, for example, the electrode of fig. 6c, where the wider top of the electrodes 212,214 are configured to wear out earlier than the narrower bottom of the electrodes 212, 214. Additionally or alternatively, such a change in capacitance may be achieved by arranging the top portions of the electrodes 212,214 closer to each other than the bottom portions, as indicated in fig. 6 g. As indicated in FIG. 1g, it is also possible to use a separate capacitor 210₁、210₂、210₃、210₄And 210₅(capacitor 210)₆Is the base capacitor) to achieve the corresponding effect. In such a case, the capacitor 210 is close to the surface 120₁May have capacitors 210 further from surface 120₂A larger capacitance. Further, the base capacitor 210₆May be higher than the other capacitor 210₁、210₂、210₃、210₄And 210₅The capacitance of (c).

As indicated above, it may be beneficial to have a reasonably large capacitance c 1. This value can be designed, for example, such that the resonance frequency of the circuit is maintained at a reasonable level throughout the lifetime of the circuit. As shown by curve 840 in fig. 3, capacitance c1 may increase (relative to curve 830). May pass through a base capacitor 216 (e.g., the base capacitor of FIG. 6d) or the deepest arranged capacitor 210₆To achieve such an increase.

In an embodiment, the primary capacitive member 210 is configured such that for a first wear value w1, the derivative of the capacitance c1 of the primary capacitive member 210 with respect to wear w has a first capacitance change value dc1/dw | w1, and for a second wear value w2, the derivative of the capacitance c1 of the primary capacitive member 210 with respect to wear w has a second capacitance change value dc1/dw | w 2. In an embodiment, the first capacitance change value dc1/dw | w1 is different from the second capacitance change value dc1/dw | w 2. In a preferred embodiment, the first wear value w1 is less than the second wear value w2, and the first capacitance change value dc1/dw | w1 is negative and less than the second capacitance change value dc1/dw | w 2. In practice, the derivative can only be measured as a differential from two different measurements. The derivative dc1/w | w1 may be calculated as a derivative measured from a range of 0.5 mm, which includes a small wear value w 1. The derivative dc1/w | w2 may be calculated as a derivative measured from a range of 0.5 mm, which includes the larger wear value w 2.

Fig. 6a to 6i show embodiments of the circuit 200. These figures only show the primary capacitive component 210 and the primary inductive component 220. The circuit 200 may further include a resistive member. Furthermore, the wires in the middle of the member have a certain resistance.

In fig. 6a, the primary capacitive member 210 is formed by a first plate forming a first electrode 212 and a parallel second plate forming a second electrode 214. Between the electrodes 212,214 some non-conductive material 213 is arranged. The resistivity of such material 213 may be, for example, at least 10 Ω m at 20 ℃. To have mechanical stability, material 213 is preferably a solid dielectric material. Preferably, the solid dielectric material 213 is a solid under at least typical use conditions, such as at temperatures from-55 ℃ to +150 ℃ (such as from-55 ℃ to +100 ℃). The dielectric material 213 may also be solid at other temperatures, however, preferably the dielectric material 213 does not melt or vaporize at the aforementioned temperature ranges.

In fig. 6b, portions of the electrodes 212,214 form a base capacitor 216. In fig. 6c, the capacitance change is designed to be initially larger than later, as discussed in more detail above. In fig. 6d, a base capacitor 216 has been added to the electrode of fig. 6 c.

In fig. 6e, the electrodes 212,214 are arranged concentrically. The outer electrode 212 has the shape of a generalized cylinder (such as an elliptical generalized cylinder); preferably, the outer electrode is a regular (i.e. circular) cylinder. The inner electrode 214 may be a rod or a cylinder. Preferably, some solid dielectric material 213 is disposed intermediate the inner and outer electrodes. In fig. 6f, a base capacitor 216 has been added to the electrode of fig. 6 e. In fig. 6g, the diameter of the outer electrode 212 is smaller near the wear surface than at a location further away from the wear surface. As discussed in more detail above, this has the following effect: the capacitance change is designed to be larger initially than later. In addition, the embodiment of fig. 6g includes a base capacitor.

In fig. 6h, the primary capacitive member 210 includes a first electrode 212 that forms a capacitance with a grounded electrode 214 (i.e., a second electrode). However, as indicated in fig. 6i, the circuit may also function without the ground electrode 214. In this embodiment, a capacitance is formed between the first electrode 212 and the environment in which the first electrode 212 is disposed. However, it has been noted that the measurement is more accurate when the primary capacitive member 210 comprises a first electrode 212 and a second electrode 214. The measurement is also accurate when discrete capacitors are used (see fig. 1 g).

Referring to fig. 1g, the primary capacitive member 210 need not include a plate. For example, the primary capacitive member 210 may include a capacitor 210₁、210₂、210₃、210₄、210₅And 210₆It may be, for example, a discrete component. As the tire wears, the member and/or its wiring also wears, thereby changing the capacitance of the primary capacitive member 210. In such a case, the capacitors are arranged electrically in parallel such that each of the capacitors increases the capacitance of the member 210.

Referring to, for example, fig. 8a and 8b, in an embodiment, the body 110 comprises a first material and defines a blind hole 112 for the circuit 200. In an embodiment, the circuit 200 is disposed in the blind hole 112. Further, the primary capacitance member 210 includes (a, i) at least a first electrode 212 or (a, ii) a capacitor 210_i(i-1, 2, 3, 4, 5, 6), and (b) a dielectric material 213, such that at least some of the dielectric material 213 remains in (c) the portion of the body 110 and (d, i) the first electrode 212 or (d, ii) the capacitor 210 in a direction perpendicular to a normal N1 to the first surface 120_iIn the middle. Further, it should be noted that the electrodes 212,214 generally form at least part of a capacitor. Furthermore, preferably, the dielectric material 213 is not the same material as the first material. Such an embodiment may be fabricated, for example, by forming the blind hole 112 into the wear surface 120 (e.g., the tread 120 of a tire) and then inserting the circuit 200 into the blind hole 112. Such a method for manufacturing is typically much easier than, for example, arranging the circuit 200 into the body 110 during polymerization of the body 110. Furthermore, forming the blind hole 112 to the solidified or otherwise solid body 110 ensures that the circuit is arranged in the correct orientation and in the correct position. Such blind holes may, for example, be made during the vulcanisation of the tyre, for example by passingIs formed using a tire mold. In the alternative, blind holes may be made (e.g., drilled) after vulcanization.

As indicated above and in fig. 8a and 8b, in an embodiment, the primary capacitive member 210 comprises a second electrode 214, and at least some of the dielectric material 213 is arranged intermediate the first electrode 212 and the second electrode 214. As indicated in fig. 8a and 8b, some of the dielectric material 213 is also left intermediate the body 110 and the first electrode 212 in a direction perpendicular to the normal N1 of the first surface 120.

In a preferred embodiment, the primary inductive member 220 and the second inductive member 320 are arranged with respect to each other such that their magnetic fields are strongly coupled. Further, in a preferred embodiment, the body 110 is formed of a solid material, and the primary inductance member 220 and the second inductance member 320 are rigidly fixed to the body 110. This has the following effect: the mutual orientation and distance of the primary inductive member 220 and the second inductive member 320 remains constant in use, which significantly improves the sensitivity of the measurement and simplifies the analysis of the measured data.

Correspondingly, in an embodiment the primary inductive means 220 is configured to form a primary magnetic field B1 and the secondary inductive means 320 is configured to form a secondary magnetic field B2 as known to the skilled person, the direction of such magnetic fields depends to a large extent on the point of view however, in the center of the primary inductive means 220 the primary magnetic field B1 points to the primary direction db1, which applies at least to the center of the primary coil 222 comprised by the primary inductive means 220. furthermore, in the center of the secondary inductive means 320 the secondary magnetic field B2 points to the secondary direction db2, which applies at least to the center of the secondary coil 322 comprised by the secondary inductive means 320 in order to have a strong coupling between the magnetic fields B1 and B2, in an embodiment, for example in the embodiment of fig. 4a, the angle α between the primary direction dB1 and the secondary direction dB2 is smaller than 30 degrees or larger than 150 degrees, preferably smaller than 15 degrees or larger than 165 degrees.

However, referring to fig. 4c, angle α need not be small, for example, primary core 224 (such as primary axis 224) may be used to direct primary magnetic field B1 in a similar manner, secondary core 324 (such as secondary axis 324) may be used to direct secondary magnetic field B2 in fig. 4c, secondary core 324 includes a turn whereby secondary core 324 is configured to direct secondary magnetic field B2 to form a strong interaction with primary magnetic field B1 in fig. 4a, primary core 224 (i.e., primary axis 224) is straight, however, a technician may readily shape cores 224, 324 to increase the magnetic interaction, in order to direct primary magnetic field B1, in an embodiment, primary core 224 includes a paramagnetic or ferromagnetic material, in an embodiment, secondary core 324 includes a paramagnetic or ferromagnetic material, in order to direct secondary magnetic field B2.

Further, in a preferred application, the primary direction dB1 is substantially parallel to the normal of the wear surface 120. for example, the angle β between the primary direction dB1 and the normal N1 of the first surface 120 may be less than 30 degrees or greater than 150 degrees, such as less than 15 degrees or greater than 165 degrees. herein, the normal N1 refers to the normal of the surface 120 at the point closest to the primary capacitive member 210. this has the effect that the primary inductive member 220 and the secondary inductive member 320 may be arranged in close proximity to each other when the secondary inductive member 320 is arranged on opposite sides of the body 110 as compared to the surface 120 (the circuit 200 is configured to measure its wear).

Referring to fig. 4b, in an embodiment, the apparatus 100 includes a first reinforcing structure 150. The purpose of the first reinforcing structure 150 is to reinforce the device 100. For example, the first reinforcing structure 150 may be a metal coating of the body 110 arranged such that the first reinforcing structure 150 forms the second surface 130 (see, e.g., fig. 1 b). In the alternative, the first reinforcing structure 150 may be a wire mesh or a belt disposed inside the body 110. The first reinforcing structure 150 may be a belt of the tire 100. Since the purpose of the first reinforcing structure 150 is to reinforce the body 100, it is preferable that the reinforcing structure does not restrict a large aperture. More precisely, preferably, the first reinforcing structure 150 is not limited to having at least 0.5 cm²Of the area of (a). Large apertures will weaken the reinforcing structure. However, when the first reinforcing structure 150 does not have the aperture, in the embodimentA portion of the first reinforcing structure 150 is disposed intermediate the primary inductive member 220 and the secondary inductive member 320.

The reinforcing structure (such as a belt) typically comprises metal, as metal is substantially strong. However, the metal is also generally well conductive, whereby it hinders the magnetic coupling between the primary inductive member (220) and the secondary inductive member (320). In an embodiment, the first reinforcing structure 150 includes a resistivity of at most 1 Ω m at a temperature of 23 ℃ (such as at most 10 Ω m at a temperature of 23 ℃)^-5Resistivity of Ω m). In particular, in such a case, the mutual distance and arrangement between the inductive components (220, 320) becomes important. The first reinforcing structure 150 may comprise steel, or it may be constructed of steel. The first reinforcing structure 150 may include a steel mesh.

Additionally or alternatively, the first reinforcing structure 150 (such as a belt) may comprise a fibrous material. The fibrous material of the first reinforcing structure 150 may comprise at least one of cotton, rayon, polyamide (nylon), polyester, polyethylene terephthalate, and poly-p-phenylene terephthalamide (kevlar).

Referring to fig. 4c, in an embodiment, the apparatus 100 comprises a second reinforcing structure 155. Portions of the second reinforcing structure 155 may also be disposed intermediate the primary inductive member 220 and the secondary inductive member 320. However, the first reinforcing structure 150 may provide sufficient reinforcement, whereby the second reinforcing structure 155 may restrict the aperture (i.e., the orifice) and even portions of the second reinforcing structure 155 do not remain intermediate the primary inductive member 220 and the secondary inductive member 320.

The second reinforcing structure 155 may comprise a fibrous material. The fibrous material of the second reinforcing structure 155 may include at least one of cotton, rayon, polyamide (nylon), polyester, polyethylene terephthalate, and poly-p-phenylene terephthalamide (kevlar).

Referring to fig. 1f, the magnetic coupling between the inductive components 220, 320 may be improved by using one or two plates 225, 325 composed of ferromagnetic or paramagnetic materials, such as ferrite or metals including iron. The wear indicator 190 may include a primary plate 225 configured to enhance the magnetic field of the primary inductive member 220. As indicated in fig. 1f, an imaginary axis surrounded by the primary inductive component 220 penetrates the primary plate 225. The imaginary axis may be parallel to the primary magnetic field B1 generated by the primary inductive component 220, in particular the primary coil 222, at its center. In this way, primary plate 225 is magnetically connected to primary coil 222. As indicated in fig. 1f, preferably the primary board 225 is not arranged in-between the primary inductive component 220 and the secondary inductive component 320.

Additionally or alternatively, the wear indicator 190 may include a secondary plate 325, the secondary plate 325 configured to enhance the magnetic field of the secondary inductive component 320. As indicated in fig. 1f, an imaginary axis surrounded by the secondary inductive component 320 penetrates the secondary plate 325. The imaginary axis may be parallel to the secondary magnetic field B2 generated by the secondary inductive member 320, in particular the secondary coil 322, at its center. In this manner, secondary plate 325 is magnetically connected to secondary coil 322. As indicated in fig. 1f, preferably the secondary board 325 is not arranged in-between the primary inductive component 220 and the secondary inductive component 320.

Referring to fig. 5a, in general, the primary inductive member 220 includes a primary coil 222 wound about a primary axis AX1, and the secondary inductive member 320 includes a secondary coil 322 wound about a secondary axis AX 2. Such axes (AX1, AX2) may be clearly defined physical axes, which for example comprise ferromagnetic or paramagnetic materials. For example, in fig. 4c, the primary coil 222 is wound around a primary core 224, the primary core 224 being an axis, thus forming a primary axis AX1 (compare fig. 5 a). In this manner, the primary core 224 is magnetically connected with the primary coil 222. In addition, in this manner, secondary core 324 is magnetically connected to secondary coil 322. Further, in fig. 4c, secondary coil 322 is wound around a portion of secondary core 324. Thus, the corresponding portion (on which the secondary coil 324 is wound) forms the secondary axis AX 2.

However, the coils may be formed on the circuit board in a planar form, whereby the centers of the coils will define the corresponding axes. Furthermore, the coil need not enclose any solid material. As known to the skilled person, the direction of the primary axis AX1 is parallel (i.e. unidirectional or reverse) to the aforementioned primary direction dB1, and the direction of the secondary axis AX2 is parallel (i.e. unidirectional or reverse) to the aforementioned secondary direction dB 2.

Referring to fig. 5a, the primary coil 222 has a primary cross-section XS1 in a plane having a normal parallel to the primary axis AX 1; and the secondary coil 322 has a secondary cross-section XS2 in a plane having a normal parallel to the secondary axis AX 2. Expressed alternatively, the primary coil 222 is configured to form a primary magnetic field B1, the primary magnetic field B1 is directed in the primary direction dB1 at the center of the primary coil 222, and the primary coil 222 has a primary cross section XS1 on a plane having a normal parallel to the primary direction dB 1. In a similar manner, the secondary coil 322 is configured to form a secondary magnetic field B2, the secondary magnetic field B2 is directed in the secondary direction dB2 at the center of the secondary coil 322, and the secondary coil 322 has a secondary cross-section XS2 in a plane having a normal parallel to the secondary direction dB 2. Herein, the primary cross-section XS1 is limited by the outermost periphery of the primary coil 222. In addition, the secondary cross-section XS2 is defined by the outermost perimeter of the secondary coil 322. The coils 222, 322 may be disposed on a printed circuit board, such as a multilayer printed circuit board.

Referring to fig. 5B, in order to have a strong coupling between the magnetic fields B1 and B2, in an embodiment the primary cross-section XS1 and the secondary cross-section XS2 are arranged relative to each other such that an imaginary straight line IML parallel to the primary direction dB1 and/or the secondary direction dB2 penetrates both the primary cross-section XS1 and the secondary cross-section XS 2. This embodiment is shown in fig. 5 b.

As indicated in fig. 5b, preferably primary cross-section XS1 and secondary cross-section XS2 overlap by a reasonable amount, as indicated in fig. 5b, directions dB1 and dB2 are parallel, cross-sections XS1 and XS2 may project in direction dB1 onto the same plane P with a normal in direction dB1 as indicated in fig. 5b, the overlapping part XS12 of the cross-sections is the intersection of the projections of cross-sections XS1 and XS2 onto plane P (in a mathematical sense, usually represented by XS1 ∩ XS2), in case directions dB1 and dB2 are not parallel, it can be considered that the projections of XS1 and XS2 project in either of directions dB1 or dB2 onto the same plane P with a normal in directions dB1 or dB2, respectively.

As indicated in fig. 5b, the area Axs12 of the overlapping portion XS12 is reasonably large compared to the area Axs1 of the primary cross-section XS1 and/or the area Axs2 of the secondary cross-section XS 2. It should also be noted that the area Axs1 of the primary cross-section XS1 is equal to the area Axs1 of the projection of the primary cross-section XS1 onto a plane. In a similar manner, the area Axs2 of the secondary cross-section XS2 is equal to the area Axs2 of the projection of the secondary cross-section XS2 onto the plane P. In a preferred embodiment, the area Axs12 of the overlapping portion XS12 of the primary and secondary cross-sections XS1, 2 is at least 25% (such as at least 33% or at least half) of the smaller of: an area Axs1 of the primary cross-section XS1 and an area Axs2 of the secondary cross-section XS 2. More preferably, the area Axs12 of overlapping portion XS12 is at least 66%, at least 75%, or at least 90% of the smaller of Axs1 and Axs 2.

In addition, good magnetic coupling of the coils 222, 322 has been observed when the cross-sectional dimension of the primary coil 222 is of the same order as the cross-sectional dimension of the secondary coil 322. Thus, preferably, the ratio of the cross-sectional areas of the coils 322, 222 (i.e., Axs2/Axs1) is from 0.1 to 10, such as from 0.2 to 5.

However, it may be preferable to keep the circuit 200 small, at least in some tires. Thus, in embodiments, the ratio Axs2/Axs1 of the area Axs2 of the secondary cross-section XS2 to the area Axs1 of the primary cross-section XS1 is at least 0.5 or at least 0.75 or at least 0.9. However, as indicated above, if the area difference is too large, the magnetic coupling begins to decrease. Thus, the ratio Axs2/Axs1 may be, for example, in the range from 0.5 to 10 or from 0.75 to 7 or from 0.9 to 5.

In addition, good magnetic coupling of the coils 222, 322 has been observed when the distance d12 (see fig. 4a) between the primary inductive member 220 and the secondary inductive member 320 is small. For example, in an embodiment, the distance d12 is at most 75 mm, such as at most 50 mm, at most 25 mm, at most 15 mm, or at most 10 mm.

Referring to fig. 7, in an embodiment, interrogator 300 is configured to communicate with gateway device 400. Gateway device 400 may be configured to display a wear value, for example, for a user. The gateway device 400 may be configured to compare the wear value to a limit value. The gateway device 400 may be configured to send an alarm signal when the wear value exceeds a limit value. Such an alarm signal may be optical or visual. Such an alarm signal may be sent to the user.

In addition or in the alternative, the gateway device 400 may be configured to communicate with a service provider, such as a mobile telephone network. For example, the gateway device 400 may be configured to communicate with a cloud service via a mobile phone network. In the alternative, interrogator 300 may communicate with a service provider (such as a mobile telephone network) directly or, for example, via a mobile telephone network. However, having gateway device 400 reasonably located near interrogator 300 reduces the power consumption of interrogator 300. Typically, this is beneficial because power supply 330 of interrogator 300 may be difficult to change or charge.

Preferably, interrogator 300 is configured to send data to gateway device 400, and gateway device 400 is arranged at most 50 meters (preferably at most 20 meters, such as at most 10 meters) away from interrogator 300. Preferably, the gateway apparatus 400 is configured to transmit and receive data from the cloud server 500. Interrogator 300 may be configured to communicate with gateway device 400 via bluetooth technology. Interrogator 300 may be configured to wirelessly communicate with gateway device 400 using radio waves in a frequency range from 2.4 GHz to 2.485 GHz.

In an embodiment, interrogator 300 is configured to measure at least one of: [i] the mutual inductance of the secondary capacitive member 320 and the circuit 200, [ ii ] the inductance of the circuit 200, and [ iii ] the resonant frequency of oscillation of the circuit 200. As detailed above, such measured data is indicative of the wear w of the first surface 120. Further, in an embodiment, interrogator 300 is configured to use the measured data (i.e., data indicative of wear) to determine a wear value w. The interrogator 300 may transmit the wear value to the gateway apparatus 400 or directly to the cloud server 500. In the alternative, interrogator 300 may send data indicative of wear to gateway device 400 or directly to cloud server 500. Correspondingly, the gateway apparatus 400 or the cloud server 500 may be configured to determine the wear value w using the received data indicative of wear.

An embodiment of the present invention is also a system for measuring the wear w of a surface 120. Such a system includes device 100 (i.e., a tire having circuit 200 and interrogator 300 attached thereto) and gateway device 400. Interrogator 300 of device 100 is configured to transmit data to gateway device 400. Gateway device 400 is configured to receive data from interrogator 300. The gateway device 400 may be configured to communicate with a user as indicated above. The gateway device 400 may be configured to communicate with the cloud server 500 as indicated above.

It is possible to receive a wear indicator 190 (see fig. 1a) comprising a separate circuit 200 and a separate interrogator 300. Further, tire 100 with a wear indicator may be formed by arranging circuit 200 and interrogator 300 relative to each other and body 110 of the tire following the principles presented hereinabove. Correspondingly, a wear indicator 190 is disposed to the body 110. As indicated above, the body 110 may be a tread or a tread block of a tire (e.g., a pneumatic tire).

An embodiment of such a method includes receiving (e.g., arranging for availability) a wear indicator 190. As indicated above, the wear indicator 190 includes: [i] a circuit 200 including a primary inductive component 220 and a primary capacitive component 210 configured to wear; and [ ii ] interrogator 300, which includes power supply 330, communication circuit 310, and secondary inductive component 320. In this method, at least part of the primary capacitive member 210 of the circuit 200 is arranged into the body 110 (i.e. the tread of the tire). The tread may include a tread block, and the primary capacitive members 210 may be arranged into the tread block. Further, embodiments include arranging the primary inductive member 220 of the circuit 200 relative to the body 110 such that at least a portion of the primary capacitive member 210 is closer to the wear surface 120 than at least a portion of the primary inductive member 220. Further, interrogator 300 is attached to body 110 or circuit 200. Interrogator 300 is attached such that at least a portion of secondary inductive member 320 is disposed farther from wear surface 120 than a portion of primary inductive member 220.

A preferred embodiment includes attaching interrogator 300 to another surface 130 of tire 100. The surface may be the surface 130 of the cavity of the tire. Surface 130 may be an interior surface of a tire, which is a pneumatic tire. Embodiments include attaching interrogator 300 at least partially into tire 100.

Fig. 9a shows a tire 100, which is a pneumatic tire. As is well known, a tire has a tread 120. The tread 120 is the exterior surface of the tire. The tread is formed as the surface of the tread block assembly 114. The tread block assembly 114 includes tread blocks 110, as indicated in fig. 9a, the tread blocks 110 arranged such that one or more grooves remain in the middle of the tread blocks 110. Correspondingly, a single tread block 110 forms at least part of the tread 120, typically only part of the tread 120. Tread 120 is intended for making rolling contact against surface 900 when pneumatic tire 100 is in use. The tread 120 has a surface normal substantially parallel to a radial direction SR of the tire 100, the radial direction SR being perpendicular to the axis of rotation AXR of the tire 100.

Pneumatic tire 100 is an example of device 100 discussed above. The tread blocks of pneumatic tire 100 form a body having a wear surface 120. In the case of a pneumatic tire, the wear surface 120 is the tread of the pneumatic tire 100.

Referring to fig. 9b, the tire 100 includes a tread block 110. At least the tread blocks are provided with an electrical circuit 200 as indicated hereinabove. The circuit 200 is arranged in the tread block such that when the tread 120 is worn, the primary capacitive member 210 is also worn. As the tread 120 wears, the portion of the tread 120 formed by the surface of the tread block 110 having the electrical circuit 200 also wears. The primary capacitive member 210 is electrically coupled to the primary inductive member 220. Interrogator 300 is disposed on interior surface 130 of pneumatic tire 100. The primary inductive member 220 is aligned with the secondary inductive member 320 in the manner discussed in detail above.

As indicated above, in the pneumatic tire 100, the distance d12 (see fig. 4a) between the primary inductive member 220 and the secondary inductive member 320 is typically at most 75 mm. However, the closer the inductive members 220, 230 are to each other, the better the magnetic coupling between the inductive members 220, 320 is typically. Therefore, as indicated above, the distance d12 is preferably small.

In pneumatic tire 100, tread blocks 110 comprise a first material, such as rubber. Furthermore, in an embodiment, the circuit 200 is arranged in the blind hole 112 of the tread block 110. Accordingly, the tread block 110 defines the blind hole 112 for the circuit 200. Blind holes may be arranged into tread blocks 110 prior to arranging at least part of circuit 200 or the entire circuit 200 into the blind holes of the tread blocks. The blind holes may be made in the mold during curing of the tire 100, or may be made (e.g., drilled) after curing.

Referring also to fig. 8a and 8b, in such embodiments, at least some of the dielectric material 213 of the primary capacitive member 210 remains with the first electrode 212 or the capacitor 210 at the portion of the tread block 110 in a direction perpendicular to the normal N1 of the tread 120₁In the middle. Preferably, the dielectric material 213 is not the same material as the first material. Preferably, however, primary capacitive members 210 are at most as wear resistant as tread 120. Thus, the dielectric material 213 may be reasonably soft. For example, the dielectric material 213 may be at most as wear resistant as the tread 120.

When the circuit 200 and interrogator are arranged as part of a pneumatic tire 100, the gateway device 400 (see fig. 7) may be arranged in an automobile with a pneumatic tire configured to be arranged on a wheel of the automobile.

Referring to fig. 9b, pneumatic tire 100 typically includes a reinforcing band 150. The reinforcing band 150 includes a first cord (cord). At least some of the first cords typically comprise metal, such as steel. In the alternative, or in addition, the first cords may comprise a fibrous material, such as at least one of glass fibers, carbon fibers, aramid fibers, and para-aramid fibers (i.e., Kevlar @). When the first ply comprises steel, the reinforcing strip 150 is commonly referred to as steel strip 150. Most typically, steel belts are used to reinforce the tire 100. In an embodiment, the reinforcing tape 150 includes a resistivity of at most 1 Ω m at a temperature of 23 ℃ (such as at most 10 at a temperature of 23 ℃)^-5Resistivity of Ω m). In particular, in such a case, the mutual distance and arrangement between the inductive components (220, 320) becomes important.

Because the purpose of the reinforcement band 150 is reinforcement, the reinforcement band 150 is preferably complete, i.e., not provided with large holes. Correspondingly, in an embodiment, a portion of the stiffening band 150 is disposed intermediate the primary inductive member 220 and the secondary inductive member 320. In particular, when the reinforcing band 150 is disposed intermediate the inductive members 220 and 320 and the reinforcing band 150 comprises steel, the mutual alignment of the primary inductive member 220 and the secondary inductive member 320 is important. A short mutual distance d12 as discussed above and/or having substantially parallel magnetic fields as indicated by the directions dB1 and dB2 above also improve the coupling in these cases.

As indicated in fig. 9b, an embodiment of the pneumatic tire 100 includes one layer 155 or a plurality of layers 155. The layer or layers 155 include rubber as a base material and a second ply integral with the base. The second cord fabric may comprise a fibrous material. The fibrous material of the second cords may comprise at least one of cotton, rayon, polyamide (nylon), polyester, polyethylene terephthalate and poly-p-phenylene terephthalamide (kevlar). The second ply reinforces the ply or plies 155.

In an embodiment, the portion of the layer 155 or the portion of at least one of the plurality of layers 155 is disposed intermediate the primary inductive member 220 and the secondary inductive member 320. This has the following effect: the layer 155 or layers 155 may also be made integral, i.e. not provided with large holes. Thus, the reinforcing effect of the layer is fully utilized.

However, the reinforcing effect of the belt 150 may be sufficient. In such a case, the layer or layers 155 may restrict the pores. In such embodiments, the primary inductive member (220) and the secondary inductive member 320 are arranged relative to the aperture such that the layer 155 or layers 155 are not left intermediate the primary inductive member 220 and the secondary inductive member 320.

Where interrogator 300 is disposed inside pneumatic tire 100, interrogator 300 preferably includes secondary sensor assembly 340 as discussed hereinabove. Secondary sensor assembly 340 may include, for example, (1) a pressure sensor, (2) an acceleration sensor, (3) a pressure sensor and an acceleration sensor, (4) a pressure sensor and a temperature sensor, (5) a pressure sensor, a temperature sensor, and an acceleration sensor; or any other combination of pressure sensors, acceleration sensors and temperature sensors.

Where interrogator 300 is disposed inside non-pneumatic tire 100, interrogator 300 preferably includes secondary sensor assembly 340 as discussed hereinabove. The secondary sensor assembly 340 may include, for example, (1) an acceleration sensor, (2) a temperature sensor, or (3) an acceleration sensor and a temperature sensor.

Pneumatic tire 100 with wear indicator 190 may be manufactured, for example, by arranging available circuitry 200 and interrogator 300 as detailed above. Further, at least part of the primary capacitive members 210 of the circuit 200 are arranged into the tread block 110 and the primary inductive members 220 are arranged into the pneumatic tire 100 such that at least part of the primary capacitive members 210 are closer to the tread 120 than at least part of the primary inductive members 220. Preferably, the primary inductive member 220 is also arranged in the tread block 110. As indicated above, the circuit 200 may be arranged, for example, in the blind hole 112 of the tread block.

Further, interrogator 300 is attached to a surface of a cavity bounded by the tire (e.g., interior surface 130 of pneumatic tire 100) or at least partially into tire 100 such that at least a portion of secondary inductive member 320 is arranged further from tread 120 than a portion of primary inductive member 220. Preferably, interrogator 300 is attached to interior surface 130 of pneumatic tire 100.