Abstract: A power transmission belt having longitudinally spaced pairs of blocks on the opposite surfaces of a neutral belt portion thereof. The blocks are formed of hard synthetic resin materials having fibers distributed therein. The fibers may be provided in the form of distributed short fibers, fabrics, and one or more different types of fibers may be utilized in the respective blocks. The fibers include carbon fibers, aramid fibers, and silicon carbide fibers. The neutral belt is provided with longitudinally spaced projections on the upper and lower surfaces thereof and the blocks are provided with complementary recesses receiving the projections. The recesses are preferably deeper than the height of the projections, whereby the distal surfaces of the blocks may be urged with high frictional engagement against the flat surfaces of the neutral belt.

Abstract: A power transmission belt having longitudinally spaced pairs of blocks on the opposite surfaces of a neutral belt portion thereof. The blocks are formed of hard synthetic resin materials having fibers distributed therein. The fibers may be provided in the form of distributed short fibers, fabrics, and one or more different types of fibers may be utilized in the respective blocks. The fibers include carbon fibers, aramid fibers, and silicon carbide fibers. The neutral belt is provided with longitudinally spaced projections on the upper and lower surfaces thereof and the blocks are provided with complementary recesses receiving the projections. The recesses are preferably deeper than the height of the projections, whereby the distal surfaces of the blocks may be urged with high frictional engagement against the flat surfaces of the neutral belt.