50 and 52 and the posts 42 and 44 extend through these slots to guide sliding movement of the push button extensions post 46 extends through slots 54 in slidable cam followers and serves to guide sliding movement thereof in the module the followers are aligned with and are actuable by the push button extensions such followers are designated by the same numbers as the actuating push button extensions but have a subscript f added thereto in place of the e used in association with the numbers identifying the extensions the cam followers are operable by rotatable cams 56 of which there is one for each follower a pivoted wobble plate 58 is operable by the cam followers and a needle bight controllong member 59 is operable by the wobble plate acting through link 60 and bell crank 61 all in the manner described in the aforementioned patent application plates 34 36 38 and 40 are preferably of a resilient plastic material each of the plates is formed with through openings which include an enlarged end portion 62 and a narrower portion 64 extending to the edge 66 of the plate when the module 20 is assembled the posts 42 44 and 46 are threaded through the.