US Patent 7568976 Rotary coupling

A coupling connects a drive part with a driven part. One of the parts are formed with axially extending coupling formations. The coupling has a one-piece plastic body formed with a central hub formed with axially extending coupling formations complementary to the formations of the one part and fitted axially to the one part and with a plurality of connection regions projecting radially from the hub securable to the other of the parts. Each of the connection regions is formed with an axially throughgoing hole. The coupling further has respective metallic elements fitted in the holes and each fixed to the other part. These elements fit with play in the respective holes. Formations on the elements and on the connection regions secure the elements in the connection regions against displacement out of the connection regions in either of two axially opposite directions prior to fixing of the elements to the other part.