JP2012250666A - Attachment structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an attachment structure that prevents peel-off from the inner surface of a tire while suppressing deterioration in durability.SOLUTION: The attachment structure includes a pedestal 210 having: a pedestal bottom surface 211 bonded to the inner surface of a tire; a pedestal upper surface 212 provided on the side opposite to the pedestal bottom surface 211; and a pedestal slope 213 continuous from the end of the pedestal bottom surface 211 to the end of the pedestal upper surface 212. The pedestal slope 213 has a shape recessed toward the center of the pedestal 210 in the tire circumferential direction.

Description

  The present invention relates to a mounting structure for attaching a functional component having a function of detecting the state of a tire to the inner surface of the tire.

  Conventionally, a pair of bead cores, a carcass layer having a toroidal shape straddling between a pair of bead cores, a belt layer disposed adjacent to the carcass layer, and a bead core, a carcass layer, and a rubber layer covering the belt layer Tires equipped are known.

  The tire includes a bead portion having a bead core, a tread portion having a tire tread surface, a sidewall portion forming a side surface of the tire, and a shoulder portion provided across the sidewall portion and the tread portion.

  In addition, a functional component attached to a rubber layer (inner liner) constituting the inner surface of the tire is known. The functional component is, for example, a sensor module that measures temperature, pressure, and the like inside the tire. In general, the functional component is attached to the inner liner by a rubber patch or the like (for example, Patent Document 1).

JP 2007-055347 A

  By the way, the shape of the inner liner is different between a state in which the tire is in contact with the road surface (ground state) and a state in which the tire is not in contact with the road surface (non-ground state). That is, the inner liner has a flat shape in the grounding state, and the inner liner has an arc shape in the non-grounding state.

  In order to absorb such deformation of the inner liner, it is conceivable to use a relatively soft rubber as a material constituting the rubber patch or the like. However, if a relatively soft rubber is used, the durability is lowered.

  Then, this invention is made | formed in order to solve the subject mentioned above, and provides the attachment structure which can suppress peeling from the inner surface of a tire, suppressing the fall of durability. With the goal.

The attachment structure according to the first feature is a structure for attaching a functional component having a function of detecting a state of a tire to the inner surface of the tire. The mounting structure is constituted by an elastic member, and is formed from a pedestal bottom surface bonded to the inner surface of the tire, a pedestal top surface provided on the opposite side of the pedestal bottom surface, and an end portion of the pedestal bottom surface in the tire circumferential direction. A pedestal having a pedestal slope continuous with an end portion of the pedestal upper surface in the tire circumferential direction is provided. The pedestal slope has a recessed portion that is recessed with a curvature radius R toward the center of the pedestal in the tire circumferential direction. In the cross section along the tire circumferential direction, a is a point that is farthest from the inner surface of the tire among the hollow portions, and b is a point that contacts the inner surface of the tire among the hollow portions, c is an intersection of the lower surface of the pedestal that intersects a perpendicular line extending from the b to the lower surface of the pedestal, ac is a line segment connecting the a and the c, and bc is the b and c A is the shorter length of ac and bc, and B is the longer length of ac and bc. When A and B satisfy the condition of 1/3 ^0.5 × B <A <B, R is (A ² + B ² ) / (2 × A) <R <(A ² + B ² ) ^Satisfies the relationship of ^0.5 .

  1st characteristic WHEREIN: The said hollow part contains the part which contact | connects the said base lower surface among the said base slopes.

In the first aspect, if the A and the B satisfy the condition of A ^{<1/3 0.5} × B, wherein R ^is a ^{(A 2 + B 2) /} (2 × A) < relation R Fulfill.

  ADVANTAGE OF THE INVENTION According to this invention, the attachment structure which makes it possible to suppress peeling from the inner surface of a tire can be provided, suppressing the fall of durability.

FIG. 1 is a view showing a tire 100 according to the first embodiment. FIG. 2 is a view showing the tire 100 according to the first embodiment. FIG. 3 is a view showing the mounting structure 200 according to the first embodiment. FIG. 4 is a diagram illustrating the frame body 220 according to the first embodiment. FIG. 5 is a diagram illustrating the frame body 220 according to the first embodiment. FIG. 6 is a diagram illustrating the frame body 220 according to the first embodiment. FIG. 7 is a view showing the insertion piece 250 according to the first embodiment. FIG. 8 is a view showing the insertion piece 250 according to the first embodiment. FIG. 9 is a diagram showing a pedestal 210 according to the first embodiment. FIG. 10 is a diagram illustrating the pedestal 210 according to the first embodiment. FIG. 11 is a view for explaining assembly of the mounting structure 200 according to the first embodiment. FIG. 12 is a view for explaining assembly of the mounting structure 200 according to the first embodiment. FIG. 13 is a view for explaining assembly of the mounting structure 200 according to the first embodiment. FIG. 14 is a diagram illustrating a pedestal 210 according to the first modification. FIG. 15 is a diagram illustrating a pedestal 210 according to the first modification. FIG. 16 is a diagram illustrating a pedestal 210 according to the first modification. FIG. 17 is a view for explaining the stress generated between the pedestal 210 and the tire 100. FIG. 18 is a view for explaining the stress generated between the pedestal 210 and the tire 100. FIG. 19 is a diagram for explaining the relationship between the radius of curvature of the base slope 213 and the shear stress. FIG. 20 is a diagram for explaining the evaluation results. FIG. 21 is a diagram for explaining the evaluation results.

  Hereinafter, an attachment structure according to an embodiment of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

  However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones. Therefore, specific dimensions and the like should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

[Outline of Embodiment]
The mounting structure according to the embodiment is a structure for mounting a functional component having a function of detecting the state of the tire on the inner surface of the tire. The mounting structure is constituted by an elastic member, and is formed from a pedestal bottom surface bonded to the inner surface of the tire, a pedestal top surface provided on the opposite side of the pedestal bottom surface, and an end portion of the pedestal bottom surface in the tire circumferential direction. A pedestal having a pedestal slope continuous with an end portion of the pedestal upper surface in the tire circumferential direction is provided. The pedestal slope has a recessed portion that is recessed with a curvature radius R toward the center of the pedestal in the tire circumferential direction. In the cross section along the tire circumferential direction, a is a point that is farthest from the inner surface of the tire among the hollow portions, and b is a point that contacts the inner surface of the tire among the hollow portions, c is an intersection of the lower surface of the pedestal that intersects a perpendicular line extending from the b to the lower surface of the pedestal, ac is a line segment connecting the a and the c, and bc is the b and c A is the shorter length of ac and bc, and B is the longer length of ac and bc. When A and B satisfy the condition of 1/3 ^0.5 × B <A <B, R is (A ² + B ² ) / (2 × A) <R <(A ² + B ² ) ^Satisfies the relationship of ^0.5 .

  In the embodiment, since the pedestal slope has a recessed portion that is recessed toward the center of the pedestal in the tire circumferential direction, peeling from the inner surface of the tire is suppressed. In addition, since there is no need to use soft rubber, a decrease in durability of the pedestal is suppressed.

Further, when A and B satisfy the condition of 1/3 ^0.5 × B <A <B, R is (A ² + B ² ) / (2 × A) <R <(A ² + B ² ) ^{0 .5} relationship is satisfied. Therefore, the curvature radius R of the base slope can be determined appropriately.

[First Embodiment]
(Tire composition)
Below, the composition of the tire concerning a 1st embodiment is explained. FIG.1 and FIG.2 is a figure which shows the tire 100 which concerns on 1st Embodiment.

  First, as illustrated in FIG. 1, the tire 100 includes a bead portion 10, a sidewall portion 20, a shoulder portion 30, and a tread portion 40.

  The bead portion 10 is provided on the innermost side in the tire radial direction among the portions constituting the tire 100. The bead portion 10 is continuously provided along the tire circumferential direction. The bead part 10 is a part for fixing the tire 100 to the rim. The bead portion 10 is covered with rubber.

  The sidewall portion 20 is provided outside the bead portion 10 in the tire radial direction among the portions constituting the tire 100. The sidewall portion 20 is continuously provided along the tire circumferential direction. The sidewall portion 20 constitutes the side surface of the tire 100. The sidewall portion 20 is covered with rubber.

  The shoulder portion 30 is provided between the sidewall portion 20 and the tread portion 40 among the portions constituting the tire 100. The shoulder portion 30 is continuously provided along the tire circumferential direction. The shoulder portion 30 is covered with rubber.

  The tread portion 40 is a portion that constitutes a tire tread that contacts the road surface among the portions that constitute the tire 100. The tread portion 40 is continuously provided along the tire circumferential direction. On the tire tread surface of the tread portion 40, for example, a tread pattern formed by a groove extending in the tire circumferential direction (circumferential groove), a groove extending in the tire width direction (width direction groove), or the like is provided. .

  Secondly, the tire 100 includes a bead core 110, a carcass layer 120, and a belt layer 130, as shown in FIGS.

  The bead core 110 includes a bead core 110 </ b> A and a bead core 110 </ b> B, and configures the bead unit 10. The bead core 110 has a ring shape and is configured by a bead wire (not shown).

  The carcass layer 120 has a toroidal shape straddling between the bead core 110A and the bead core 110B. The carcass layer 120 is composed of, for example, a plurality of carcass cords (not shown) extending along the tire radial direction (or tire width direction). The carcass layer 120 is folded back at the bead core 110 toward the outside in the tire width direction.

  The belt layer 130 includes a belt layer 130 </ b> A and a belt layer 130 </ b> B and constitutes the tread portion 40. The belt layer 130 is disposed on the outer side in the tire radial direction with respect to the carcass layer 120. The belt layer 130 has a configuration in which a belt cord is covered with rubber. The belt cord provided in the belt layer 130A may intersect with the belt cord provided in the belt layer 130B.

(Configuration of mounting structure)
Below, the structure of the attachment structure which concerns on 1st Embodiment is demonstrated. FIG. 3 is a view showing the mounting structure 200 according to the first embodiment. Here, it should be noted that the mounting structure 200 is bonded to the inner surface of the tire 100. Specifically, the attachment structure 200 is bonded to the inner surface of the tire 100 extending along the tire circumferential direction, that is, the inner surface of the tire 100 constituting the tread portion 40.

  As shown in FIG. 3, the mounting structure 200 includes a pedestal 210, a frame body 220, a base body 230, a functional component 240, and an insertion piece 250.

  The pedestal 210 is configured by an elastic member (elastomer). For example, the pedestal 210 is made of natural rubber or synthetic rubber. The pedestal 210 has a pedestal lower surface bonded to the inner surface of the tire 100 and a pedestal upper surface provided on the opposite side of the pedestal lower surface. For example, the pedestal 210 is bonded to the inner surface of the tire 100 by vulcanization bonding. A functional component 240 is provided on the upper surface of the base 210 via the frame body 220 and the base body 230.

  In addition, it is preferable that the Young's modulus of the elastic member which comprises the base 210 is 30 Mpa or less. When the pedestal 210 is bonded to the inner surface of the tire 100 having a small outer shape, the change in the radius of curvature of the tread portion 40 becomes large. Therefore, the Young's modulus of the elastic member constituting the pedestal 210 is preferably 1 MPa or more and 7 MPa or less. .

  The frame body 220 is configured by a member having a predetermined rigidity. The frame body 220 is disposed on the pedestal upper surface of the pedestal 210. For example, the surface of the frame body 220 is brass-plated, the pedestal 210 contains cobalt, and the frame body 220 is bonded to the pedestal 210 by vulcanization adhesion.

  In the first embodiment, the frame body 220 has a box shape that accommodates the base body 230. Details of the frame 220 will be described later (see FIGS. 4 to 6).

  The base body 230 is configured by a member having a predetermined rigidity. A functional component 240 is placed on the base body 230. In the first embodiment, the base body 230 has a substantially rectangular parallelepiped shape and is accommodated in the frame body 220.

  The functional component 240 has a function of detecting the state of the tire 100. The functional component 240 is, for example, a pressure sensor that detects the internal pressure of the tire 100, a temperature sensor that detects the internal temperature of the tire 100, an acceleration sensor that detects the rotational speed of the tire 100, and the like.

  The insertion piece 250 is configured by a member having a predetermined rigidity. The insertion piece 250 is inserted into the frame body 220 and restricts the movement of the base body 230 accommodated in the frame body 220. In the first embodiment, the insertion piece 250 has a U shape and restricts the movement of the base body 230 in the direction perpendicular to the inner surface of the tire 100. The details of the insertion piece 250 will be described later (see FIGS. 7 and 8).

(Frame structure)
Below, the structure of the frame which concerns on 1st Embodiment is demonstrated. FIG. 4 is a diagram illustrating the frame body 220 according to the first embodiment.

  As shown in FIG. 4, the frame body 220 includes a bottom plate 221, a pair of first wall bodies 222 (first wall body 222 </ b> A and first wall body 222 </ b> B), and a pair of side wall locking pieces 223 (side wall engagement). Stop piece 223A and side wall locking piece 223B), a second wall body 224, and a second wall body 225.

  The bottom plate 221 has a frame lower surface disposed on the pedestal upper surface and a frame upper surface provided on the opposite side of the frame lower surface. The upper surface of the frame is defined by a first direction and a second direction that intersects the first direction. A base body 230 is placed on the upper surface of the frame of the bottom plate 221. In the first embodiment, the bottom plate 221 has a plate shape, and has a rectangular frame upper surface.

  The first wall body 222A and the first wall body 222B are provided on the bottom plate 221. The first wall body 222 </ b> A and the first wall body 222 </ b> B have a shape that stands in a direction perpendicular to the bottom plate 221. The first wall body 222A and the first wall body 222B extend along the first direction. The first wall body 222A and the first wall body 222B are provided with an interval in a second direction intersecting the first direction.

  In the first embodiment, the first wall body 222 </ b> A constitutes a side wall locking piece 223 </ b> A that bends toward the first wall body 222 </ b> B in the second direction as a tip in a direction perpendicular to the bottom plate 221. The side wall locking piece 223A extends along the first direction. Similarly, the first wall body 222B constitutes a side wall locking piece 223B that bends toward the first wall body 222A in the second direction as a tip in a direction perpendicular to the bottom plate 221. The side wall locking piece 223B extends along the first direction.

  The second wall body 224 is provided on the bottom plate 221. The second wall body 224 has a shape that stands in a direction perpendicular to the bottom plate 221. The second wall body 224 extends along the second direction. In the first embodiment, the second wall body 224 has a plate shape and is provided at one end of the bottom plate 221 in the first direction.

  The second wall body 225 is provided on the bottom plate 221. The second wall body 225 has a shape that stands in a direction perpendicular to the bottom plate 221. The second wall body 225 extends along the second direction. In the first embodiment, the second wall body 225 has a plate shape and is provided at the other end of the bottom plate 221 in the first direction.

  In addition, the 2nd wall body 224 and the 2nd wall body 225 are provided in the 1st direction at intervals. In the first embodiment, in order to insert the base body 230 along the first direction, the height of at least one of the second wall body 224 and the second wall body 225 is the first wall body 222 in the vertical direction. It is preferable that the height is smaller than the height.

  Thus, in the first embodiment, the bottom plate 221, the first wall body 222, the second wall body 224, and the second wall body 225 form a box shape.

  In 1st Embodiment, it illustrates about the case where the attachment structure 200 is adhere | attached on the tire 100 so that a 1st direction may turn into a tire width direction. In the following, for clarity of explanation, the first direction is referred to as the tire width direction, the second direction is referred to as the tire circumferential direction, and the vertical direction is referred to as the tire radial direction.

(Frame dimensions)
Below, the dimension of the frame which concerns on 1st Embodiment is demonstrated. 5 and 6 are views showing the frame body 220 according to the first embodiment. 5 and 6 show a state in which the base body 230 is accommodated in the frame body 220. FIG.

As shown in FIG. 5, the height from the upper surface of the frame body 220 to the side wall locking piece 223 is H ₂₂₃ in the tire radial direction. In the tire radial direction, the height of the base body 230 is _H230 . The difference between the height H ₂₂₃ and the height H ₂₃₀ is D ₁ . In the tire circumferential direction, the length of the base body 230 is _L230 .

In the first embodiment, the distance between the pair of first wall bodies 222 is equal to the length L ₂₃₀ of the base body 230 in the tire circumferential direction. Therefore, the movement of the base body 230 in the tire circumferential direction is restricted by the pair of first wall bodies 222. In other words, the base body 230 is disposed on the upper surface of the frame body 220 so as to fit between the pair of first wall bodies 222.

As described below, in the tire radial direction, the difference D ₁ is equal to the height of the arms of the pair provided on the insert 250. Therefore, the movement of the base body 230 in the tire radial direction is restricted by the pair of arm portions.

As shown in FIG. 6, the heights of the second wall body 224 and the second wall body 225 are H ₂₂₅ in the tire radial direction. In the tire width direction, the width of the base body 230 is _W230 .

In the first embodiment, the distance between the second wall body 224 and the second wall body 225 is equal to the width W _{230 of the} base body 230 in the tire width direction. Therefore, the movement of the base body 230 in the tire width direction is restricted by the second wall body 224 and the second wall body 225.

In the first embodiment, the difference between the height H ₂₂₃ and the height H ₂₂₅ is preferably larger than the height H ₂₃₀ of the base body 230. Accordingly, it is easy to insert the base body 230 into the frame body 220 along the tire width direction.

(Configuration of insert piece)
Below, the structure of the insertion piece which concerns on 1st Embodiment is demonstrated. 7 and 8 are views showing the insertion piece 250 according to the first embodiment. 7 shows a state after the insertion piece 250 is attached to the frame body 220, and FIG. 8 shows a state before the insertion piece 250 is attached to the frame body 220.

  As shown in FIGS. 7 and 8, the insertion piece 250 includes a pair of arm portions 251 (an arm portion 251A and an arm portion 251B) and a pair of tip folding pieces 252 (a tip folding piece 252A and a tip folding piece 252B). And a connecting portion 253 and a pair of overhang portions 254 (an overhang portion 254A and an overhang portion 254B).

  The arm portion 251A and the arm portion 251B extend along the tire width direction. Further, the arm portion 251A and the arm portion 251B have flexibility in the tire circumferential direction. For example, the arm portion 251A and the arm portion 251B have a flat plate shape in which the thickness in the tire circumferential direction is smaller than the thickness in the tire radial direction.

  The tip of the arm portion 251A constitutes a tip folding piece 252A that bends to the outside of the insertion piece 250 in the tire circumferential direction. Similarly, the tip of the arm portion 251B constitutes a tip folding piece 252B that bends outside the insertion piece 250 in the tire circumferential direction.

The angle θ ₁ formed by the main body of the arm portion 251 and the tip folding piece 252 is preferably an acute angle. That is, the angle theta ₁ the tip of the arm portion 251 (tip folded piece 252) is folded such that the acute angle.

  The tip folded piece 252 is configured to be hooked on the first wall body 222 after the insertion piece 250 is attached to the frame body 220. That is, the tip folding piece 252 has a function of preventing the insertion piece 250 from coming off along the tire width direction.

  The tip folding piece 252 prevents the insertion piece 250 from coming off to the A side in the tire width direction after the insertion piece 250 is attached to the frame body 220.

  The connecting part 253 is a part that connects the roots of the arm part 251A and the arm part 251B. The connecting portion 253 has an overhanging portion 254A that bends from the root of the arm portion 251A to the outside of the insertion piece 250 in the tire circumferential direction. Similarly, the connecting portion 253 has an overhanging portion 254B that bends outward from the insertion piece 250 in the tire circumferential direction from the base of the arm portion 251B.

The angle θ ₂ formed by the extension line of the main body of the arm portion 251 and the overhang portion 254 is preferably an acute angle. That is, as the angle theta ₂ is an acute angle, a portion continuous to the root of the arm portion 251 (protruding portion 254) is folded.

  The overhanging portion 254 has a function of preventing the insertion piece 250 from entering the B side in the tire width direction after the insertion piece 250 is attached to the frame body 220. On the other hand, when the insertion piece 250 is removed from the frame body 220, the tip folded piece 252 can be caught by moving the insertion piece 250 toward the B side in the tire width direction.

Here, the length of the tip folded piece 252 is L ₂₅₂ in the tire circumferential direction. The length of the overhang portion 254 in the tire circumferential direction is _{L 254.} Length L ₂₅₂ is preferably equal to length L ₂₅₄ . As a result, the insertion piece 250 is not easily removed from the frame body 220.

In the tire width direction, the length of the arm portion 251 is _W251 . The length _{W 251} of the arm portion 251 is preferably equal to the length of the first wall 222 in the tire width direction. As a result, the insertion piece 250 is not easily removed from the frame body 220.

As shown in FIG. 8, before the insertion piece 250 is attached to the frame body 220, the gap G _tip at the _tip of the arm part 251 is preferably larger than the _root gap G _root of the arm part 251. Due to the flexibility of the arm portion 251, the insertion piece 250 is difficult to come off from the frame body 220.

(Configuration of pedestal)
Below, the structure of the base which concerns on 1st Embodiment is demonstrated. FIG. 9 is a diagram showing a pedestal 210 according to the first embodiment. It should be noted that the frame body 220 and the base body 230 are omitted in FIG.

  As shown in FIG. 9, the pedestal 210 includes a pedestal lower surface 211 bonded to the inner surface of the tire 100, a pedestal upper surface 212 provided on the opposite side of the pedestal lower surface 211, and an end portion of the pedestal lower surface 211 in the tire circumferential direction. A pedestal slope 213 continuous with the end of the pedestal upper surface 212 in the circumferential direction;

  The pedestal slope 213 has a hollow portion that is recessed with a curvature having a curvature radius R toward the center of the pedestal 210 in the tire circumferential direction. The hollow portion includes a portion of the pedestal slope 213 that is in contact with the pedestal lower surface 211. In other words, the pedestal slope 213 has a recessed portion at a portion in contact with the pedestal lower surface 211.

  In addition, in 1st Embodiment, the case where the whole base slope 213 is comprised by the hollow part is illustrated.

  Here, in the cross section in the tire circumferential direction, the meaning of each abbreviation is as follows.

a is a point farthest from the inner surface of the tire 100 in the pedestal slope 213 (indented portion) b is a point in contact with the inner surface of the tire 100 in the pedestal inclined surface 213 (indented portion) c is in the lower surface 211 of the pedestal , B intersecting with a perpendicular line dropped to the pedestal lower surface 211,
ab is a line segment connecting a and b. ac is a line segment connecting a and c. bc is a line segment connecting b and c. A is the shorter length of ac and bc. Here, as will be described later, as the radius of curvature R of the recessed portion of the pedestal slope 213 is smaller, the shear stress generated between the inner surface of the tire 100 and the pedestal lower surface 211 is reduced. To do. In particular, when the radius of curvature R is smaller than (A ₂ + B ₂ ) ^{0.5, the} stress generated by the front-rear input is reduced. Therefore, the maximum value of the radius of curvature R is preferably (A ₂ + B ₂ ) ^0.5 .

However, when 1/3 ^0.5 × B = A, the relationship of (A ² + B ² ) / (2 × A) = (A ² + B ² ) ^0.5 is satisfied. In such a case, as shown in FIG. 10, the circle with the radius of curvature R is a circle in contact with the horizontal line passing through b. In such a case, the radius of curvature R cannot be made smaller than the value of “(A ² + B ² ) / (2 × A)”.

Thus, a ^{1/3 0.5} × B <case condition A is satisfied (1), it is necessary to be divided into a case (2) the condition of A ^{<1/3 0.5} × B is satisfied .

In the case (1), since the relationship of (A ² + B ² ) / (2 × A) <(A ² + B ² ) ^0.5 is established, the minimum value of the radius of curvature R is (A ² + B ² ) / ( 2 × A). Therefore, the radius of curvature R satisfies the relationship of (A ² + B ² ) / (2 × A) <R <(A ² + B ² ) ^0.5 .

In the case (2), since the relationship of (A ² + B ² ) ^0.5 <(A ² + B ² ) / (2 × A) is established, the minimum value of the radius of curvature R is (A ² + B ² ) / ( 2 × A). Therefore, the curvature radius R satisfies the relationship (A ² + B ² ) / (2 × A) <R.

(Assembly of mounting structure)
Hereinafter, assembly of the mounting structure according to the first embodiment will be described. FIGS. 11-13 is a figure for demonstrating the assembly | attachment of the attachment structure 200 which concerns on 1st Embodiment.

  As shown in FIG. 11, the base body 230 on which the functional component 240 is placed is disposed on a frame body 220 attached to the upper surface of the base 210. Subsequently, the insertion piece 250 is inserted along the tire width direction. Specifically, the insertion piece 250 is disposed so that the arm portion 251 is inserted along the tire width direction between the first wall body 222 and the functional component 240. Thereby, as shown in FIG. 12, the assembly of the attachment structure 200 is completed.

As shown in FIG. 13, in the tire radial direction, the height _{H 223} of the bottom surface is provided on the bottom plate 221 to the sidewall engaging piece 223, the height of the height _{H 230} and the arm portion 251 of the base 230 _{H 251} Is preferably equal to the sum of That is, the height _{H 251} of the arm portion 251 is equal to the difference _{D 1} of the height _{H 223} and height _{H 230.}

(Function and effect)
In the first embodiment, the pedestal slope 213 has a recessed portion that is recessed toward the center of the pedestal 210 in the tire circumferential direction, so that peeling from the inner surface of the tire 100 is suppressed. Further, since there is no need to use soft rubber, a decrease in durability of the pedestal 210 is suppressed.

In the case (1) where the condition of 1/3 ^0.5 × B <A <B is satisfied, the curvature radius R is (A ² + B ² ) / (2 × A) <R <(A ² + B ² ) ^Satisfies the relationship of ^0.5 . Therefore, the radius of curvature R of the recessed portion of the pedestal slope can be appropriately determined.

Similarly, in the case (2) where the condition of A <1/3 ^0.5 × B is satisfied, the radius of curvature R satisfies the relationship of (A ² + B ² ) / (2 × A) <R. Therefore, the radius of curvature R of the recessed portion of the pedestal slope can be appropriately determined.

[Modification 1]
Hereinafter, Modification Example 1 of the first embodiment will be described. In the following, differences from the first embodiment will be mainly described.

  In the first modification, variations in the shape of the base slope 213 will be described. Specifically, as shown in FIG. 14, the entire base slope 213 may be configured with a curvature having a curvature radius R. Alternatively, as shown in FIG. 15, the pedestal slope 213 is configured by a plurality of straight lines, and may approximately form a curve with a radius of curvature R. Or as shown in FIG. 16, the base slope 213 may be comprised by the some curve from which a curvature radius differs.

  In the case shown in FIG. 16, it should be noted that the recessed portion having the curvature of the radius of curvature R is a portion including a portion of the pedestal slope 213 that is in contact with the pedestal lower surface 211.

[Stress generated between the pedestal and the inner surface of the tire]
Hereinafter, the stress generated between the pedestal 210 (the lower surface of the pedestal) and the inner surface (inner liner) of the tire 100 will be described.

(Swing motion)
Hereinafter, the swing motion will be described with reference to FIG. As shown in FIG. 17, when the mounting structure 200 is bonded to the inner surface of the tire 100, when the tire 100 contacts the road surface, the centripetal force generated along with the rotation of the tire 100 depends on the portion of the mounting structure 200. Different.

  Specifically, in the tire circumferential direction (rotation direction), the tire 100 corresponding to the front portion of the mounting structure 200 is grounded to the road surface, and the tire 100 corresponding to the rear portion of the mounting structure 200 is grounded to the road surface. Think about a case that hasn't. In such a case, the centripetal force at the front portion of the mounting structure 200 is smaller than the centripetal force at the rear portion of the mounting structure 200. Therefore, in the tire circumferential direction (rotation direction), a stress that falls to the front side with respect to the mounting structure 200 is applied.

  Similarly, in the tire circumferential direction (rotation direction), the tire 100 corresponding to the front portion of the mounting structure 200 is not grounded to the road surface, and the tire 100 corresponding to the rear portion of the mounting structure 200 is grounded to the road surface. Think about the case. In such a case, the centripetal force at the rear portion of the mounting structure 200 is smaller than the centripetal force at the front portion of the mounting structure 200. Therefore, in the tire circumferential direction (rotation direction), stress that falls to the rear side with respect to the mounting structure 200 is applied.

  As the tire 100 rotates, when the stress that falls to the front side or the stress that falls to the rear side (that is, the longitudinal stress) is repeatedly applied to the mounting structure 200, the mounting structure 200 behaves like swinging the neck back and forth. Arise. As a result, a stress (stress generated by front-rear input) generated between the pedestal 210 (the pedestal lower surface) and the inner surface (inner liner) of the tire 100 is generated.

(Deformation of inner liner)
Hereinafter, the deformation of the inner liner will be described with reference to FIG. As shown in FIG. 18, the shape of the inner liner is different between a state in which the tire 100 is in contact with the road surface (ground state) and a state in which the tire 100 is not in contact with the road surface (non-ground state). That is, the inner liner has a flat shape in the grounding state, and the inner liner has an arc shape in the non-grounding state.

  When the grounding state (flat shape) and the non-grounding state (arc shape) are repeated as the tire 100 rotates, the stress (bending) generated between the base 210 (the bottom surface of the base) and the inner surface (inner liner) of the tire 100. Stress caused by input).

[Curve radius of dent]
Hereinafter, the radius of curvature of the recessed portion will be described with reference to FIG. As shown in FIG. 19, the shearing stress generated between the inner surface of the tire 100 and the pedestal lower surface 211 decreases as the radius of curvature R of the recessed portion of the pedestal slope 213 decreases.

  In the measurement shown in FIG. 19, the dimensions of each member are as follows.

Adhesive length of pedestal 210 = 41 mm
Adhesive width of pedestal 210 = 35 mm
Thickness of pedestal 210 = 6 mm
Installation length of functional component 240 = 26 mm
Mounting width of functional component 240 = 35 mm
bc = 8.5mm (B)
ac = 6.0 mm (A)
ab = (A ₂ + B ₂ ) ^0.5 = 10.4 mm
As shown in FIG. 19, when the curvature radius R of the hollow part of the base slope 213 is 10 mm or less, the stress produced by the front-rear input is reduced. Accordingly, it is preferable that the radius of curvature R is smaller than (A ₂ + B ₂ ) ^0.5 .

[Evaluation result 1]
Hereinafter, the evaluation result 1 will be described with reference to FIG. Specifically, Example 1 and Comparative Examples 1 to 3 were prepared. In detail, the curvature radius R of the hollow part of the base slope 213 was changed, and the stress generated by the front-rear input (at the time of front-rear input) and the stress generated by the bending input (at the time of bending input) were measured.

  Here, as for the stress generated by the front-rear input, 300 N was added as the inertial force f acting on the functional component 240 (center of gravity X), and the stress generated at the end of the base 210 (base lower surface 211) in the tire circumferential direction was measured. . With respect to the stress caused by the bending input, the pedestal bottom surface 211 is artificially deformed so that the radius of curvature R of the pedestal bottom surface 211 (inner surface of the tire 100) becomes 300 mm in the tire circumferential direction, and the pedestal 210 (pedestal in the tire circumferential direction) The stress generated at the end of the lower surface 211) was measured.

(Common conditions)
Adhesive length of pedestal 210 = 41 mm
Adhesive width of pedestal 210 = 35 mm
Thickness of pedestal 210 = 3 mm
Installation length of functional component 240 = 26 mm
Mounting width of functional component 240 = 35 mm
Young's modulus of elastic member constituting base 210 = 7 MPa
bc = 8.5mm (B)
ac = 6.0 mm (A)
ab = (A ₂ + B ₂ ) ^0.5 = 10.4 mm
As shown in FIG. 20, the smaller the radius of curvature R, the lower the stress generated by the front-rear input. On the other hand, the smaller the curvature radius R, the greater the stress generated by bending input. Therefore, it was confirmed that the optimal value of the radius of curvature R was (A ₂ + B ₂ ) ^0.5 = 10.4 mm, considering the balance between the stress caused by the longitudinal input and the stress caused by the bending input.

It was confirmed that the curvature radius R is preferably smaller than (A ₂ + B ₂ ) ^0.5 because the stress generated by the front-rear input decreases as the curvature radius R decreases.

[Evaluation result 2]
Hereinafter, the evaluation result 2 will be described with reference to FIG. Specifically, Example 2 and Comparative Examples 4 to 6 were prepared. Specifically, in the same manner as in the evaluation result 1, the curvature radius R of the recessed portion of the pedestal slope 213 was changed, and the stress caused by the front-rear input (at the time of front-rear input) and the stress generated by the bending input (at the time of bending input) were measured. .

(Common conditions)
Adhesive length of pedestal 210 = 41 mm
Adhesive width of pedestal 210 = 35 mm
Thickness of pedestal 210 = 6 mm
Functional component 240 mounting length = 21 mm
Mounting width of functional component 240 = 35 mm
Young's modulus of elastic member constituting base 210 = 7 MPa
bc = 10mm (B)
ac = 9mm (A)
ab = (A ₂ + B ₂ ) ^0.5 = 13.45 mm
As shown in FIG. 21, the smaller the radius of curvature R, the lower the stress generated by the front-rear input. On the other hand, the smaller the curvature radius R, the greater the stress generated by bending input. Therefore, it was confirmed that the optimal value of the radius of curvature R was (A ₂ + B ₂ ) ^0.5 = 10.4 mm, considering the balance between the stress caused by the longitudinal input and the stress caused by the bending input.

It was confirmed that the curvature radius R is preferably smaller than (A ₂ + B ₂ ) ^0.5 because the stress generated by the front-rear input decreases as the curvature radius R decreases.

[Other Embodiments]
Although the present invention has been described with reference to the above-described embodiments, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  In the embodiment, the attachment structure 200 is exemplified as the case having the frame body 220, the base body 230, and the insertion piece 250, but the embodiment is not limited thereto. The attachment structure 200 may not include the frame body 220, the base body 230, and the insertion piece 250. That is, the mounting structure 200 may be configured only by the pedestal 210.

  In the embodiment, the term “equal” is used as a dimension expression, but it is needless to say that a dimensional error can be allowed.

  It should be noted that the “predetermined rigidity” used in the embodiment is at least larger than the rigidity of a member (elastic member) constituting the pedestal.

  In the embodiment, the shape of the upper surface of the frame body 220 is a rectangular shape. However, the embodiment is not limited to this. Specifically, the shape of the frame body upper surface of the frame body 220 may be a triangular shape or other shapes.

  DESCRIPTION OF SYMBOLS 10 ... Bead part, 20 ... Side wall part, 30 ... Shoulder part, 40 ... Tread part, 100 ... Tire, 110 ... Bead core, 120 ... Carcass layer, 130 ... Belt layer, 200 ... Mounting structure, 210 ... Base, 211 ... lower surface of base, 212 ... upper surface of base, 213 ... slope of base, 220 ... frame body, 221 ... bottom plate, 222 ... first wall body, 223 ... side wall locking piece, 224 ... second wall body, 225 ... second wall body , 230 ... Base, 240 ... Functional parts, 250 ... Insert piece, 251 ... Arm part, 252 ... Folded end piece, 253 ... Connection part, 254 ... Overhang part

Claims (3)

A mounting structure for attaching a functional component having a function of detecting the state of the tire to the opposite side of the tire,
It is constituted by an elastic member, a pedestal lower surface bonded to the inner surface of the tire, a pedestal upper surface provided on the opposite side of the pedestal lower surface, and from the end of the pedestal lower surface in the tire circumferential direction, the tire circumferential direction A pedestal having a pedestal slope continuous with the end of the pedestal top surface
The pedestal slope has a recessed portion that is recessed with a curvature radius R toward the center of the pedestal in the tire circumferential direction,
In the cross section along the tire circumferential direction,
a is a point most distant from the inner surface of the tire among the hollow portions;
b is a point in contact with the inner surface of the tire among the hollow portions;
c is an intersection that intersects with a perpendicular drawn from the b to the pedestal bottom surface of the pedestal bottom surface;
ac is a line segment connecting the a and the c;
bc is a line segment connecting b and c,
A is the shorter of ac and bc,
B is the longer of ac and bc,
When A and B satisfy the condition of 1/3 ^0.5 × B <A <B, R is (A ² + B ² ) / (2 × A) <R <(A ² + B ² ) An attachment structure characterized by satisfying a relationship of ^0.5 .   The mounting structure according to claim 1, wherein the recessed portion includes a portion of the pedestal slope that contacts the lower surface of the pedestal. In the cross section along the tire circumferential direction,
R satisfies the relationship of (A ² + B ² ) / (2 × A) <R when A and B satisfy the condition of A <1/3 ^0.5 × B. The mounting structure according to claim 1.

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