Apparatus for control of needle pushers

Claim 1

Apparatus for the control of needle pushers for knitting tools of a knitting machine comprising: a needle bed having grooves therein, knitting tools moveable to and fro in the grooves, needle pushers having lower magnetizable portions having substantially circular cross-sections and moveable to and fro in the grooves for moving the knitting tools, means covering at least a portion of the grooves and provided with knitting tool cam means and needle pusher cam means, the needle pusher cam means and knitting tool cam means causing the needle pushers to move the knitting tools, the needle pushers being moveable into different positions in accordance with different positions of knitting tool, the needle pusher cam means having two camming surfaces for moving the needle pushers to two lateral different positions along the Grooves, pivot bearing means for pivoting the needle pushers, needle pusher foot means on the needle pushers for pivotably engaging the needle pusher cam means except when the needle pushers have been pivoted into one of a plurality of pivot positions. guide channel means for the lower portion of the needle pusher which is slightly wider than said lower portion, said guide channel means having a central plane taking a substantially straight course and opening into a magnet chamber which widens in the direction of flight of the needle pushers, first and second electromagnet means in the magnet chamber having pole pieces close to the opening to the guide channel and on both sides thereof, positioned to magnetically select by deflecting said lower magnetizable portions of the needle pushers and pivot said needle pushers with high selection frequency without contacting said lower magnetizable portions of the needle pushers in their flight path at normal working speeds. the electromagnet means being energizable in accordance with a predetermined knitting pattern, for causing the needle pushers to pivot, third and fourth magnet means following the first and second electromagnet means in the magnet chamber and producing a constant magnetic field symmetrical to the central plane of the guide channel means and positioned to magnetically influence the trajectory of said lower magnetizable needle pusher portions without contacting said lower magnetizable needle pusher portions in their flight path at normal working speeds, covering foil means which cover the pole piece surfaces of said third and fourth magnet means, multi-channel path-divider means for the lower portion of the needle pushers following the magnet chamber, said first and second electromagnetic means and said third and fourth electromagnetic means being symmetrically located with respect to the central course of said guide channel means.