Shear band and a non-pneumatic tire
A shear band comprising a three-dimensional spacer structure, wherein the three-dimensional spacer structure is formed from a first and second layer of material, each layer of material having first reinforcement members which extend in a first and direction, and second reinforcement members which extend in a second direction, wherein each layer of material is connected to each other by a plurality of connecting reinforcement members which extend in a third direction, wherein the shear band further comprises a first membrane layer located radially outward of the three-dimensional spacer structure. The invention further comprises a non-pneumatic tire which includes the above described shear band.
1. A shear band comprising a three-dimensional spacer structure, wherein the three-dimensional spacer structure is formed from a first and second layer of material, each layer of material having first reinforcement members which extend in a first direction, and second reinforcement members which extend in a second direction, wherein the first and second layer of material are connected to each other by a plurality of connecting reinforcement members which extend in a third direction, wherein the shear band further comprises a first membrane layer, and wherein the shear band further comprises a first set of interwoven reinforcement members that are interwoven around the reinforcement members of the first layer of the three-dimensional spacer structure and a reinforcement cord of the first membrane layer.
2. The shear band of claim 1 further comprising a second membrane layer located radially inward of the three-dimensional spacer structure.
3. The shear band of claim 1 wherein the reinforcement cord of the first membrane layer is oriented at an angle in the range of +/−20 degrees with respect to the tire equatorial plane.
4. The shear band of claim 2 wherein the second membrane layer has reinforcement cords that are oriented at an angle in the range of +/−20 degrees with respect to the tire equatorial plane.
5. The shear band of claim 1 wherein the reinforcement cords are spaced apart a distance SS which ranges from 3 to 10 mm.
6. The shear band of claim 1 wherein the reinforcement cords are inextensible.
7. The shear band of claim 1 wherein the first direction is aligned with the circumferential direction of the shear band.
8. The shear band of claim 1 further comprising a second set of interwoven reinforcement members that are interwoven around the reinforcement members of the radially inner layer of the three-dimensional spacer structure and a reinforcement cord of the radially inner membrane layer.
9. The shear band of claim 8 wherein the interwoven reinforcement members extend in the axial direction.
10. The shear band of claim 1 wherein the first and second layers are parallel with respect to each other.
11. The shear band of claim 1 wherein the connecting reinforcement members extend in a third direction, and the third direction is aligned with the radial direction of the shear band.
12. The shear band of claim 1 wherein the first and second layers are separated by a distance Z in the range of 2 to 25 millimeters.
13. The shear band of claim 1 wherein the three-dimensional spacer structure is formed of an auxetic material.
14. A non-pneumatic tire comprising a ground contacting annular tread portion; and a shear band formed from any of the claims 1 - 7 and 8 - 13 .