Functional-component-attached housing body and tire

Abstract

Provided are a functional-component-attached housing body and a tire which are capable of improving sensing stability and the durability of a housing body while improving measurement performance of tire information by enhancing the sensing sensitivity of a functional component. This functional-component-attached housing body comprises a functional component having a sensor function for detecting tire information, and a housing body 10 in which the functional component is housed. A bottom part 11 of an inner surface of the housing body 10 has a sea-island structure composed of: at least one island part A formed as a protrusion and positioned in a lower region of a sensing part of the functional component during the housing of the functional component; at least one island part B formed as a protrusion and arranged around the island part A; and a sea part C, which is formed as a recess and is a region excluding the island part A and the island part B.

Description

Container with functional parts and tire

[0001] The present invention relates to a container with functional parts and a tire, and more particularly to a container with functional parts and a tire that can improve the sensing stability of the functional parts and the durability of the container while increasing the sensing sensitivity of the functional parts to improve the measurement performance of tire information.

[0002] In order to acquire tire information, functional components (e.g., sensor units including sensors) are installed on the inner surface of a tire (see, for example, Patent Documents 1 and 2). When installing the functional component, a container made of rubber or the like is attached to the inner surface of the tire, and the functional component is housed inside the attached container.

[0003] In such a housing with a functional component, by providing a protrusion on the bottom of the housing, the protrusion comes into contact with the sensing part of the functional component and maintains a pressed state against the sensing part, thereby improving the measurement performance of the functional component. However, in this case, the functional component is held only by the protrusion and the side of the housing, which causes the functional component to be held in an inclined state, resulting in a problem of reduced sensing stability. Alternatively, the presence of the protrusion makes the functional component more likely to move within the housing, which reduces the durability of the housing.

[0004] Japanese Patent No. 6272225 Publication Japanese Special Table No. 2016-505438

[0005] The object of the present invention is to provide a tire and a housing with functional parts that can improve the sensing stability of the functional parts and the durability of the housing while increasing the sensing sensitivity of the functional parts to improve the measurement performance of tire information.

[0006] In order to achieve the above-mentioned object, the container with functional part of the present invention comprises a functional part having a sensor function for detecting tire information and a container in which the functional part is housed, and is characterized in that the bottom of the inner surface of the container has a sea-island structure composed of at least one island part A formed as a convex part and located in a region below the sensing part of the functional part when the functional part is housed, at least one island part B formed as a convex part and arranged around the island part A, and a sea part C formed as a concave part, which is the area excluding the island parts A and B.

[0007] The tire of the present invention is characterized in that the functional part-equipped container is fixed to the inner surface of the tire, and the functional part is contained in the container.

[0008] In the present invention, the bottom of the container has a sea-island structure consisting of island portions A and B, each consisting of a convex portion, and sea portion C, each consisting of a concave portion. The island portions A press against the sensing portions of the functional components, thereby improving the sensing sensitivity of the functional components. Sensing sensitivity refers to the ability to detect changes in physical quantities caused by road impacts with high sensitivity. Improved sensing sensitivity increases the peak-to-peak value of the output waveform, making it possible to accurately grasp the timing of changes in physical quantities caused by road impacts. Furthermore, the island portions B support the functional components, preventing them from being held in an inclined position or suppressing excessive movement or vibration of the functional components within the container, thereby improving the sensing stability of the functional components and the durability of the container. The sea-island structure on the bottom of the container thus improves the sensing sensitivity of the functional components, improving tire information measurement performance, as well as the sensing stability of the functional components and the durability of the container.

[0009] In the present invention, the area a [mm 2 ] and the area b of island B [mm 2 ] and the area c of the sea portion C [mm 2] preferably satisfies the relationship 0.25≦(a+b) / c≦20.00. This makes it possible to increase the sensing sensitivity of the functional component while avoiding adverse effects on the durability of the housing and deterioration of sensing stability, thereby effectively improving sensing stability and durability of the housing.

[0010] It is preferable that the distance h [mm] from the bottom surface of the sea portion C to the maximum height of the island portion A and the distance H [mm] from the bottom surface of the sea portion C to the maximum height of the island portion B satisfy the relationship 0.1h≦H≦1.2h. This makes it possible to enjoy a balanced improvement in the sensing sensitivity of the functional component and the improvement in the sensing stability and durability of the housing.

[0011] The distance h [mm] from the bottom surface of the sea portion C to the maximum height of the island portion A is preferably in the range of 0.1 mm to 2.0 mm, which increases the sensing sensitivity of the functional components, prevents the functional components from falling off, and improves workability during storage.

[0012] The functional component preferably includes a housing that houses electronic components and at least one film-like piezoelectric element fixed to the wall surface of the housing. In this case, it is suitable for detecting the amount of wear of the tread portion as tire information.

[0013] The housing body is preferably made of vulcanized rubber having a modulus at 100% elongation of 1.0 MPa or more and less than 12.0 MPa, which makes it possible to achieve both durability of the housing body and ease of housing the functional part in the housing body.

[0014] In the present invention, it is preferable that the container is fixed to the back surface of the tread portion with an adhesive and that the container contains functional components. When such a container is used, the above-mentioned excellent effects can also be obtained.

[0015] The tire of the present invention is preferably a pneumatic tire, but may also be a non-pneumatic tire. In the case of a pneumatic tire, the interior thereof can be filled with air, an inert gas such as nitrogen, or other gases.

[0016] FIG. 1 is a perspective view showing an example of a functional component-equipped container according to an embodiment of the present invention. FIG. 2 is a perspective view showing the interior of the functional component-equipped container shown in FIG. 1, with a portion cut away. FIG. 3 is a plan view showing the functional component-equipped container shown in FIG. 1. FIG. 4 is a cross-sectional view taken along the arrows IV-IV in FIG. 3. FIG. 5 is a plan view of the bottom of the container shown in FIG. 2. FIGS. 6(a) and 6(b) are enlarged cross-sectional views showing the periphery of the bottom of the functional component-equipped container. FIG. 7 is an enlarged cross-sectional view showing the bottom of the functional component-equipped container. FIGS. 8(a) to 8(e) are each a perspective view showing a modified example of a functional component-equipped container according to an embodiment of the present invention, with a portion cut away to show the interior of the container. FIG. 9 is a meridian cross-sectional view showing an example of a pneumatic tire according to an embodiment of the present invention. FIG. 10 is a diagram showing an example of an output waveform from a piezoelectric element.

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings, in which: Figures 1 to 5 show a functional component-equipped container according to an embodiment of the present invention.

[0018] 1 to 5, the functional component 20 is housed inside a housing 10. The housing 10 has a flat bottom 11 fixed to the inner surface of the tire, a cylindrical side wall 12 protruding from the bottom 11, a housing section 13 formed by the bottom 11 and the side wall 12, and an opening 14 communicating with the housing section 13 and used to put in and take out the functional component 20. The housing section 13 is the internal region of the housing 10 excluding the thickness of the opening 14.

[0019] The bottom 11 has a sea-island structure formed by combining convex portions and concave portions. Specifically, the bottom surface 11x of the housing 10 is formed with at least one island portion A formed as a convex portion and located below the sensing portion 22 of the functional component 20 when the functional component 20 is housed therein, at least one island portion B formed as a convex portion and disposed around the island portion A, and a sea portion C formed as a concave portion, which is the area of ​​the bottom surface 11x excluding the island portions A and B. The island portions A and B may be provided with tapered or chamfered portions.

[0020] The functional component 20 has a contact surface 21 that contacts the inner surface of the tire. That is, the contact surface 21 is the surface that contacts the bottom surface 11x of the housing 10. The functional component 20 also has a structure in which various electronic components are housed inside a housing 23. The electronic components may be configured to include various sensors, transmitters, receivers, control circuits, batteries, and the like for acquiring tire information. Examples of tire information acquired by the sensors include the internal temperature and pressure of the pneumatic tire, and the amount of tread wear. For example, a temperature sensor or a pressure sensor is used to measure the internal temperature and pressure. To detect the amount of tread wear of a tire, for example, a sensing element 22 made of at least one film-like piezoelectric element is disposed on the contact surface 21 of the functional component 20. The sensing element 22 detects an output voltage corresponding to tire deformation during driving, and the amount of tread wear is detected based on the output voltage. Alternatively, an acceleration sensor or a magnetic sensor may be used.

[0021] A sensory element 22 is fixed to the wall surface of the housing 23 of the functional component 20. This sensory element 22 can be disposed on either the outer surface or the inner surface of the housing 23. Fig. 6(a) shows an example in which the sensory element 22 is provided on the outer surface of the bottom of the housing 23 of the functional component 20, and Fig. 6(b) shows an example in which the sensory element 22 is provided on the inner surface of the bottom of the housing 23 of the functional component 20. In either case, the island portion A is located below the sensory element 22 of the functional component 20 when the functional component 20 is housed.

[0022] In the present invention, the island portion A is a portion for pressing the sensing portion 22, and it is not the case that after the functional component 20 is housed, the island portion A is pressed by the functional component 20 and the bottom 11 of the housing 10 is deformed along the tire inner surface. Furthermore, the island portion A of the housing 10 and the housing of the functional component 20 are not fitted together, and no recess for fitting with the island portion A is provided in the bottom of the housing 23.

[0023] In the above-described housing with functional parts, the bottom 11 inside the housing 10 has a sea-island structure consisting of island parts A and B made up of convex parts and sea part C made up of concave parts, and the island parts A press against the sensing parts 22 of the functional parts 20, thereby increasing the sensing sensitivity of the functional parts 20. Furthermore, the island parts B support the functional parts 20, preventing the functional parts 20 from being held in an inclined state or suppressing excessive movement or vibration of the functional parts 20 inside the housing 10, thereby improving the sensing stability of the functional parts 20 and the durability of the housing 10. As such, the bottom 11 of the housing 10 has an island-sea structure, which increases the sensing sensitivity of the functional parts 20 and improves tire information measurement performance, as well as improving the sensing stability of the functional parts 20 and the durability of the housing 10.

[0024] 1 to 5, island portion A is located at the center of the bottom portion 11, and the sensing portion 22 is also located at the center of the bottom portion of the functional component 20, with the diameter of the sensing portion 22 being larger than the diameter of island portion A. In this case, the projection area formed by projecting the sensing portion 22 onto the outer surface of the housing 23 includes island portion A. Furthermore, island portion B, which is larger in diameter than the sensing portion 22, is arranged at a distance from island portion A. In the present invention, this configuration is most preferable.

[0025] In the above-mentioned functional part-equipped container, the area a [mm 2 ] and the area b of island B [mm 2 ] and the area c of the sea portion C [mm 2 ] preferably satisfies the relationship 0.25≦(a+b) / c≦20.00, and more preferably satisfies the relationship 0.40≦(a+b) / c≦6.00. By setting the area of ​​each part so as to satisfy the above relationship, it is possible to increase the sensing sensitivity of the functional component 20 while avoiding adverse effects on the durability of the housing 10 and deterioration of sensing stability, and it is possible to effectively improve the sensing stability and durability of the housing 10.

[0026] The distance h of the island portion A (see FIG. 7 ) and the distance H of the island portion B (see FIG. 7 ) preferably satisfy the relationship 0.1h≦H≦1.2h, and more preferably satisfy the relationship 0.2h≦H≦1.2h. In this case, the lower limit can be set to satisfy the relationship 0.8h≦H. Most preferably, the relationship 0.4h≦H≦1.0h is satisfied. The distance h [mm] is the distance from the bottom surface of the sea portion C to the maximum height of the island portion A, and the distance H [mm] is the distance from the bottom surface of the sea portion C to the maximum height of the island portion B. By appropriately setting the distance h of the island portion A and the distance H of the island portion B to satisfy the above relationship, it is possible to achieve a balanced improvement in the sensing sensitivity of the functional component 20 and the improvement in sensing stability and durability of the housing 10.

[0027] Here, if the ratio H / h is less than 0.1, the island portion A becomes excessively higher than the island portion B, which makes it easier for the functional component 20 to be held in an inclined state or for the functional component 20 to move easily within the housing, which tends to deteriorate the durability of the housing 10. Conversely, if the ratio H / h is more than 1.2, the island portion B becomes excessively higher than the island portion A, which makes it impossible to fully obtain the effect of keeping the sensing portion 22 of the functional component 20 pressed by the island portion A and increasing the sensing sensitivity of the functional component 20.

[0028] The distance h [mm] is preferably in the range of 0.1 mm to 2.0 mm, and more preferably in the range of 0.5 mm to 1.0 mm. By appropriately setting the distance h in this manner, it is possible to increase the sensing sensitivity of the functional component 20, prevent the functional component 20 from falling off, and improve workability during storage.

[0029] Here, if the distance h is less than 0.1 mm, it is not possible to sufficiently obtain the effect of keeping the island portion A pressing the sensing portion 22 of the functional component 20 and increasing the sensing sensitivity of the functional component 20. Conversely, if the distance h is more than 2.0 mm, problems will arise when the functional component 20 is accommodated, causing the functional component 20 to fall off or reducing workability during accommodation.

[0030] In the above-mentioned housing with functional parts, the housing 10 is preferably made of vulcanized rubber having a modulus at 100% elongation of 1.0 MPa or more and less than 12.0 MPa. By making the housing 10 have such physical properties, it is possible to achieve both durability of the housing 10 and ease of housing the functional parts 20 in the housing 10. In addition, the modulus at 100% elongation M 100 is the tensile stress at 100% elongation measured in accordance with JIS K6251.

[0031] In the present invention, the shapes of each of the island portion A, the island portion B, and the sea portion C are not particularly limited. In addition to the configuration in which one island portion B and one sea portion C are each formed in a circular ring shape as shown in Fig. 2, examples include a configuration in which one island portion B and two sea portions C are each formed in a circular ring shape as shown in Fig. 8(a), a configuration in which the island portion B is made up of two strip-shaped bodies arranged opposite each other as shown in Fig. 8(b), a configuration in which the island portion B is made up of two extension portions extending from the island portion A and arranged opposite each other as shown in Fig. 8(c), a configuration in which the island portion B is made up of eight extension portions extending from the island portion A and arranged radially from the island portion A at equal intervals as shown in Fig. 8(d), and a configuration in which the island portion B is made up of four connection portions connected to the island portion A and arranged around the island portion A at equal intervals as shown in Fig. 8(e). In all of the configurations shown in Figs. 8(a) to (e), the island portion A has a circular planar shape. It is also possible to provide a plurality of island portions A. For example, one or more grooves may be provided on the surface of one circular island portion A to divide the circular island portion A into a plurality of sectors.

[0032] In the present invention, island portion A is a portion of the convex portion of the bottom surface 11x that is located below the sensory portion 22 of the functional component 20 when the functional component 20 is housed, and island portion B is a portion that is arranged around island portion A, but the area that corresponds to island portion A is determined depending on the size of the sensory portion 22. When island portion A and island portion B are integrally formed (for example, in the case of the forms shown in FIGS. 8(c) to 8(e)), strictly speaking, depending on the size of the sensory portion 22, the portion that is located below the sensory portion 22 of the functional component 20 when the functional component 20 is housed corresponds to island portion A, and the portion that is arranged around island portion A corresponds to island portion B. Therefore, in the present invention, the point where the planar shape changes in the convex portion of the bottom surface 11x does not necessarily become the boundary between island portion A and island portion B.

[0033] 9 shows a pneumatic tire having a functional component-equipped container fixed to the inner surface of the tire. As shown in Fig. 9, the pneumatic tire has a tread portion 1 extending in the circumferential direction of the tire to form an annular shape, a pair of sidewall portions 2, 2 disposed on both sides of the tread portion 1, and a pair of bead portions 3, 3 disposed radially inward of the sidewall portions 2.

[0034] A carcass layer 4 is mounted between the pair of bead portions 3, 3. This carcass layer 4 includes a plurality of reinforcing cords extending in the tire radial direction, and is folded back from the inside to the outside of the tire around a bead core 5 disposed in each bead portion 3. A bead filler 6 made of a rubber composition and having a triangular cross section is disposed on the outer periphery of the bead core 5.

[0035] Meanwhile, multiple belt layers 7 are embedded on the outer peripheral side of the carcass layer 4 in the tread portion 1. These belt layers 7 include multiple reinforcing cords that are inclined with respect to the tire circumferential direction, and are arranged so that the reinforcing cords cross each other between layers. In the belt layers 7, the inclination angle of the reinforcing cords with respect to the tire circumferential direction is set to a range of 10° to 40°, for example. Steel cords are preferably used as the reinforcing cords of the belt layers 7. At least one belt cover layer 8 is arranged on the outer peripheral side of the belt layers 7, with the aim of improving high-speed durability, and the reinforcing cords are arranged at an angle of, for example, 5° or less with respect to the tire circumferential direction. Organic fiber cords such as nylon and aramid cords are preferably used as the reinforcing cords of the belt cover layer 8.

[0036] The above-described tire internal structure is a typical example of a pneumatic tire, but is not limited to this.

[0037] In the pneumatic tire, a container 10 containing a functional part 20 having a sensor function for detecting tire information is installed on the back surface of the tread portion 1. Such a container with a functional part can be fixed to the back surface of the tread portion 1 of the tire by, for example, an adhesive.

[0038] The tire size is 225 / 45R18, and the tire is provided with a functional part having a sensor function for detecting tire information and a housing for housing the functional part, and the tire has an area a of the island part A, an area b of the island part B, an area c of the sea part C, a ratio (a+b) / c, a ratio H / h, a distance h, a modulus M 100 Tires for the comparative example, conventional example, and examples 1 to 8 were manufactured with the values ​​set as shown in Table 1. The functional part had a sensor function using a piezoelectric element as a sensing part, and the functional part was attached to the back surface of the tread portion via a housing.

[0039] In the comparative example, no island portion is formed on the bottom of the housing, and the bottom surface is flat (considered to have only a sea portion), and in the conventional example, only island portion A is formed in the center of the bottom of the housing, and no island portion B is formed, whereas in examples 1 to 8, they have the sea-island structure shown in Fig. 2. Furthermore, in the comparative example, conventional example, and examples 1 to 8, the piezoelectric element is located in the center of the bottom of the functional component.

[0040] For these test tires, the sensing sensitivity of the functional parts and the durability of the housing were evaluated by the following test methods. The results are also shown in Table 1.

[0041] Sensing Sensitivity: Each test tire was mounted on a wheel with a rim size of 18 x 7.5 mm and mounted on a drum testing machine. A running test was conducted under conditions of an air pressure of 230 kPa, a load of 60% of the maximum load capacity, and a speed of 30 km / h. The output detected by the sensing unit (piezoelectric element) was recorded. Figure 10 shows an example of an output waveform from the piezoelectric element. In this output waveform, when the portion of the tread where the functional component is installed comes into contact with the ground, negative and positive peaks are sequentially formed in the output of the piezoelectric element over time T, resulting in a peak-to-peak value V. The average value of the peak-to-peak values ​​V of the output waveform obtained from each of the 10 measurements was then calculated. The evaluation results were expressed as an index, with the average value of the peak-to-peak values ​​V of the output waveform being set to 100 for the comparative example. A higher index value indicates better sensing sensitivity. Sensing sensitivity was evaluated in this manner.

[0042] Durability: Each test tire was mounted on a wheel with a rim size of 18 x 7.5 and attached to a drum testing machine. A running test was conducted under conditions of an air pressure of 230 kPa, a load of 60% of the maximum load capacity, and a speed of 30 km / h, and the strain value of the base portion of the side wall of the housing was measured. The evaluation results were expressed as an index using the reciprocal of the measured value, with the comparative example being set at 100. The larger the index value, the better the durability of the housing. Note that an index value of "98" or higher means that durability equivalent to or greater than that of the comparative example was obtained.

[0043]

[0044] As can be seen from Table 1, the tires of Examples 1 to 8 were superior in the sensing sensitivity of the functional parts and the durability of the housing body in comparison with the comparative example.

[0045] In the conventional example, only island portion A was formed at the bottom of the container, and island portion B was not formed, so the sensing sensitivity was good, but the durability of the container was significantly deteriorated.

[0046] DESCRIPTION OF SYMBOLS 1 tread portion 2 sidewall portion 3 bead portion 10 container 11 bottom portion 11x bottom surface 12 sidewall portion 13 container portion 14 opening 20 functional part 22 sensing portion A, B island portion C sea portion

Claims

1. A housing with a functional component, comprising a functional component having a sensor function for detecting tire information and a housing that houses this functional component, A housing with a functional component, characterized in that the bottom of the inner surface of the housing is formed as a convex portion and has a sea-island structure comprising at least one island portion A located in the area below the sensitive portion of the functional component when the functional component is housed there, at least one island portion B formed as a convex portion and arranged around island portion A, and a sea portion C formed as a recess and being the area excluding island portions A and B.

2. Area a [mm²] of the island portion A 2 ] and the area b [mm²] of the island B 2 ] and the area c [mm²] of the sea area C 2 The functional component housing according to claim 1, characterized in that the relationship between ] and 0.25 ≤ (a + b) / c ≤ 20.

00.

3. The functional component housing according to claim 1, characterized in that the distance h [mm] from the bottom surface of the sea section C to the maximum height of the island section A and the distance H [mm] from the bottom surface of the sea section C to the maximum height of the island section B satisfy the relationship 0.1h ≤ H ≤ 1.2h.

4. The functional component-equipped container according to claim 1, characterized in that the distance h [mm] from the bottom surface of the sea portion C to the maximum height of the island portion A is in the range of 0.1 mm to 2.0 mm.

5. The functional component housing according to claim 1, characterized in that the functional component comprises a housing containing an electronic component and at least one film-like piezoelectric element fixed to the wall surface of the housing.

6. The housing with a functional component according to claim 1, characterized in that the housing is made of vulcanized rubber having a modulus of 1.0 MPa or more and less than 12.0 MPa when stretched to 100%.

7. The housing with a functional component according to claim 1, characterized in that the housing is fixed to the back surface of the tread portion with an adhesive, and the functional component is housed in the housing.

8. A tire characterized in that a housing with a functional component according to any one of claims 1 to 7 is fixed to the inner surface of the tire, and the functional component is housed in the housing.