Tire noise reduction device and pneumatic tire

1. A tire noise reduction device comprising:

a noise absorbing member formed of a porous material;

a band member formed of a thermoplastic resin, the band member being formed in an annular shape in a tire circumferential direction for mounting the noise absorbing member on a tire inner surface;

a bonding member bent into a concave cross-sectional shape; and

a band bonding section at a key point where the noise absorbing member, the band member, and the bonding member are bonded by interposing the noise absorbing member between the bonding member and the band member,

wherein a band width WB (mm) of the band member and a length WY (mm) of a band bonding section in a band width direction satisfy the following formula (a) and a yield strength of the band section at the band bonding position in an 80° C. environment is 320 N or greater,

0.01< WY/WB< 0.75  (a).

2. The tire noise reduction device according to claim 1 ,

wherein the band width WB of the band member is from 20 to 70 mm.

3. The tire noise reduction device according to claim 1 ,

wherein a band thickness H (mm) in the band bonding section and a thickness h (mm) of the band member satisfy a relationship in the following formula (b),

0.4 h≤H≤0.9h  (b).

4. The tire noise reduction device according to claim 1 ,

wherein a length WY (mm) of the band bonding section in the band width direction and a bonding length L (mm) of the band bonding section in a band circumferential direction satisfy a relationship in the following formula (c),

3.5(mm 2 )≤ WY·L≤ 8.0(mm 2 )  (c).

5. The tire noise reduction device according to claim 1 ,

wherein the length WY (mm) of the band bonding section in the band width direction and the bonding length L (mm) of the band bonding section in the band circumferential direction satisfy a relationship in the following formula (d),

0.03≤ WY/L≤ 1.0  (d).

6. The tire noise reduction device according to claim 5 ,

wherein the length WY (mm) of the band bonding section in the band width direction and the bonding length L (mm) of the band bonding section in the band circumferential direction satisfy a relationship in the following formula (e),

0.03≤ WY/L≤ 0.5  (e).

7. The tire noise reduction device according to claim 1 ,

wherein the band bonding section is provided in at least two locations relative to the noise absorbing member.

8. The tire noise reduction device according to claim 1 ,

wherein a center of the band bonding section is positioned on a neutral line of the band member.

9. The tire noise reduction device according to claim 1 ,

wherein a center position of the band bonding section in a circumferential direction is from 30 to 80 mm from an end portion of the noise absorbing member.

10. The tire noise reduction device according to claim 1 ,

wherein bonding of the noise absorbing member with the band member and the bonding member is carried out by ultrasonic welding.

11. The tire noise reduction device according to claim 1 ,

wherein the band member and the bonding member are formed of the same synthetic resin material.

12. A pneumatic tire, comprising: the tire noise reduction device described in claim 1 arranged in a tire cavity space using the band member.

13. The pneumatic tire according to claim 12 ,

wherein an inner diameter (radius) R of the tire and an annular shape outer diameter (radius) r of the band member formed in the annular shape have a relationship which satisfies the following formula (c),

0.9≤ r/R≤ 0.99  (f).