Coupling with enhanced torsional, fatigue strength, and wear resistance

A coupling apparatus for use in effecting transmission of torque, speed, and hydraulic thrust from a power section of a motor to a drive shaft or output shaft, said coupling comprising a pair of mated coupling elements, each having a driver side and an unloaded surface, wherein each said coupling element comprises:

• a hub having a top end and a bottom end;
• one to four teeth protruding cantilevered from the top of the hub and each of said teeth being broader or wider at the tooth base adjacent the hub than at the top of the teeth, thereby enhancing the strength of said teeth over regular shaped teeth while still allowing for mating;
• wherein each of the teeth is irregular in shape but substantially similar one to the other for mating of the hubs to comprise the coupling, and
• wherein each of said teeth have an “S” curved side at the driver side of the coupling and a slanted back side at the unloaded surface of the coupling, such that the maximum stress on the coupling during use occurs at or near the base of the teeth, and
• wherein the coupling has improved torsional strength, fatigue strength and wear resistance over couplings with regular shaped teeth.