Indexing coupling

In a flexible coupling for connecting a pair of axially aligned shafts, which coupling includes a pair of hubs each adapted to be mounted on one of said shafts and each including axially directed slots which receive a flexible grid element which couples the hubs together, the improvement wherein one of said hubs comprises:

• an inner hub member adapted to be secured to one of said shafts and including a circular cylindrical mounting portion extending from its axially innermost end, and a first series of axially extending gear teeth formed on an external periphery;
• an outer hub member which includes said axially directed slots engaged by said grid element, said outer hub member having a central bore extending from its axially innermost end and a sleeve portion projecting axially from its opposite end, said mounting portion of said inner hub member being journaled within said central bore and said sleeve portion having a second series of axially extending gear teeth formed on an internal periphery and which are spaced from and radially aligned with said first series, the number of teeth in said second series being different from the number of teeth in said first series;
• an indexing ring axially slidable between said inner and outer hub members and having internal and external gear teeth which mate with said first and second series of gear teeth;
• an end ring connectable to the end of said sleeve portion and overlying the ends of the mating series of gear teeth to prevent removal of said indexing ring;
• a keeper plate secured to the axially innermost end of said inner hub member and overlying said axially innermost end of said outer hub member, and
• an annular spacer disposed in an annular space defined between an intermediate radial wall of said outer hub member and the inner ends of said second series of gear teeth.