Power transmission belt

1. A belt having a compression section, a tension section, and a load carrying section, the load carrying section comprising longitudinal reinforcing cords of poly(p-phenylene-2,6-benzobisoxazole), the belt being characterized by:

the reinforcing cords having a yarn twist greater than a cord twist, and the cord twist being in the range of one-forth to one-half of a ply twist of the reinforcing cords, wherein the twist multiplier of the yarn of the reinforcing cords is in the range of 1.0 to 1.5, wherein the twist multiplier of the ply of the reinforcing cords is in the range of 3.2 to 4.3, wherein the twist multiplier of the cord of reinforcing cords is in the range of 1.7 to 4.1, wherein the yarns and plies are twisted in the same direction with the cord being twisted in the opposite twist direction.

2. The belt of claim 1 wherein the reinforcing yarns have a denier in the range of 1090 dTex to 3270 dTex.

3. The belt of claim 1 wherein the belt has a longitudinal direction and the reinforcing cords are inclined at an angle of 0° to 30° relative to the longitudinal direction of the belt.

4. The belt of claim 1 wherein the reinforcing cords have a 1×4×5 construction.

5. The belt of claim 1 wherein the reinforcing cords have a 1×4×3 construction.

6. A belt having a compression section, a tension section, and a load carrying section, the load carrying section comprising longitudinal reinforcing cords of poly(p-phenylene-2,6-benzobisoxazole), the belt being characterized by:

the reinforcing cords having a yarn twist greater than a cord twist, and the cord twist being in the range of one-forth to one-half of a ply twist of the reinforcing cords, wherein the yarns and plies are twisted in the same direction with the cord being twisted in the opposite twist direction, and wherein the reinforcing cords have a 1×4×3 construction.

7. The belt of claim 6 wherein the twist multiplier of the yarn of the reinforcing cords is in the range of 1.0 to 1.5, and wherein the twist multiplier of the cord of reinforcing cords is in the range of 1.7 to 4.1.

8. The belt of claim 7 wherein the reinforcing yarns have a denier in the range of 1090 dTex to 3270 dTex.

9. The belt of claim 8 wherein the belt has a longitudinal direction and the reinforcing cords are inclined at an angle of 0° to 30° relative to the longitudinal direction of the belt.

10. The belt of claim 9 wherein the twist multiplier of the ply of the reinforcing cords is in the range of 3.2 to 4.3.

11. A belt having a compression section, a tension section, and a load carrying section, the load carrying section comprising longitudinal reinforcing cords of poly(p-phenylene-2,6-benzobisoxazole), the belt being characterized by:

the reinforcing cords having a yarn twist greater than a cord twist, and the cord twist being in the range of one-forth to one-half of a ply twist of the reinforcing cords, wherein the yarns and plies are twisted in the same direction with the cord being twisted in the opposite twist direction, and wherein the reinforcing cords have a 1×4×5 construction.

12. The belt of claim 11 wherein the twist multiplier of the yarn of the reinforcing cords is in the range of 1.0 to 1.5, and wherein the twist multiplier of the cord of reinforcing cords is in the range of 1.7 to 4.1.

13. The belt of claim 12 wherein the reinforcing yarns have a denier in the range of 1090 dTex to 3270 dTex.

14. The belt of claim 13 wherein the belt has a longitudinal direction and the reinforcing cords are inclined at an angle of 0° to 30° relative to the longitudinal direction of the belt.

15. The belt of claim 14 wherein the twist multiplier of the ply of the reinforcing cords is in the range of 3.2 to 4.3.