Means for attaching a knob to a shaft

Claim 1

A CONTROL ASSEMBLY COMPRISING A SHAFT FORMED WITH A BIFURCATED END FORMED BY AN AXIALLY EXTENDING SLOT TRANSVERSELY ACROSS SAID END TO DEFINE A PAIR OF SEPARATED SHAFT STEMS HAVING OPPOSED SPACED APART AND GENERALLY FLAT WALLS; AND A KNOB REMOVABLY ATTACHED TO SAID BIFURCATED END OF SAID SHAFT; SAID KNOB BEING MOLDED IN A SINGLE PIECE OF RESILIENT AND COMPRESSIBLE PLASTIC MATERIAL INCLUDING AN END WALL AND A BORE OPEN AT SAID END WALL; SAID BORE HAVING SIDE WALLS DEFINING A GENERALLY CYLINDRICAL SURFACE PROJECTING AXIALLY AWAY FROM SAID END WAL TERMINATING IN A BOTTOM WALL WISDTHIN SAID KNOB AXIALLY SPACED FROM SAID END WALL; A CROSS WALL DISPOSED IN SAID BORE INTEGRALLY MOLDED TO SAID BOTTOM AND SIDE WALLS EXTENDING TRANSVERSELY ACROSS SAID BORE ACCOMMODATED IN THE AXIALLY EXTENDING SLOT OF SAID BIFURCATED SHAFT FOR REMOVABLY ATTACHING SAID SHAFT AND KNOB TOGETHER IN DRIVING RELATION; SAID CROSS WALL HAVING AN AXIAL LENGTH APPROXIMATING THAT OF THE BORE AND A CENTRAL, TRANSVERSELY CURVED PORTION EXTENDING FOR A DISTANCE LESS THAN THE FULL TRANSVERSE DIMENSION OF THE CROSS WALL, FORMED WITH A CONVEX SURFACE GENERALLY PROJECTING FOR ITS AXIAL LENGTH;