Abstract: A flexible shaft coupling of a type which uses a serpentine metal grid to connect teeth on hubs attached to driving and driven shafts has the sides of the teeth made of a polymeric resin material such as a polyurethane or a reinforced nylon 6/6, lubricated with PTFE. The side faces of the teeth deflect and deform under torque load to accommodate to the grid.

Abstract: A flexible shaft coupling of the type which uses a serpentine metal grid to connect teeth on hubs attached to driving and driven shafts has the sides of the grid rung which contact the metal teeth provided with a layer of deformable material. The layer of deformable material will deform under torque load relative to the metal teeth and metal grid and absorb differences in tooth or rung spacing or parallelism to thereby insure a more even load distribution between the rungs and teeth. A preferred deformable material is a urethane having excellent tensile strength and hardness as well as good elongation, wear resistance and flexural modulus properties.