Needle positioning mechanism

Claim 1

FOR USE WITH A SEWING MACHINE HAVING A PRIMARY DRIVE MEANS FOR CONTINUOUSLY DRIVING THE NEEDLE OF THE SEWING MACHINE TO EFFECT STITCHING AND HAVING A PRIMARY BRAKE MEANS FOR BRAKING THE SEWING MACHINE NEEDLE TO TERMINATE STITCHING AND INCLUDING MEANS FOR SELECTIVELY RENDERING OPERABLE THE PRIMARY DRIVE OR THE PRIMARY BRAKE, A MECHANISM FOR AUTOMATICALLY CAUSING THE SEWING MACHINE NEEDLE TO STOP IN A DESIRED POSITION COMPRISING IN COMBINATION, NEEDLE POSITION INDEXING AND SENSING MEANS ADAPTED FOR COUPLING TO THE SEWING MACHINE NEEDLE DRIVE AND EFFECTIVE WHEN SO COUPLED FOR INDICATING THE INSTANTANEOUS POSITION OF THE NEEDLE AND SENSING AT LEAST ONE PREDETERMINED POSITION THEREOF, AUXILIARY DRIVE MEANS ADAPTED FOR COUPLING TO THE SEWING MACHINE NEEDLE DRIVE AND EFFECTIVE WHEN SO COUPLED FOR DRIVING THE SEWING MACHINE NEEDLE TO THE AFORESAID SENSABLE PREDETERMINED POSITION, AUXILIARY BRAKE MEANS ADAPTED FOR COUPLING TO THE SEWING MACHINE NEEDLE DRIVE AND EFFECTIVE WHEN SO COUPLED AND ACTUATED FOR STOPPING THE NEEDLE AT THE DESIRED POSITION, CONTROL MEANS OPERABLE BY SAID INDEXING AND SENSING MEANS FOR ACTUATING SAID AUXILIARY BRAKE AND DEACTIVATING SAID AUXILIARY DRIVE WHEN SAID PREDETERMINED NEEDLE POSITION IS SENSED, FIRST COUPLING MEANS FOR COUPLING SAID AUXILIARY DRIVE MEANS TO THE SAID NEEDLE DRIVE, AND SECOND COUPLING MEANS ADAPTED FOR DISPOSITION BETWEEN SAID SEWING MACHINE NEEDLE DRIVE ON THE ONE HAND AND SAID PRIMARY DRIVE AND BRAKE MEANS ON THE OTHER HAND AND EFFECTIVE WHEN SO DISPOSED FOR COUPLING SAID NEEDLE DRIVE TO SAID PRIMARY DRIVE MEANS ONLY AFTER THE DRIVING SPEED OF THE LATTER HAS ACHIEVED A MINIMUM PREDETERMINED VALUE AND BEING ALSO EFFECTIVE FOR DECOUPLING SAID NEEDLE DRIVE FROM SAID PRIMARY BRAKE MEANS AS SOON AS THE LATTER HAS REDUCED THE SPEED OF THE NEEDLE DRIVE TO THE AFORESAID MINIMUM PREDETERMINED VALUE, WHEREBY, WHEN SAID NEEDLE DRIVE HAS BEEN COUPLED TO SAID AUXILIARY DRIVE AND DECOUPLED FROM SAID PRIMARY BRAKE BY SAID FIRST AND SECOND COUPLING MEANS RESPECTIVELY AND WHEN SAID CONTROL MEANS HAVE BEEN OPERATED BY SAID INDEXING AND SENSING MEANS, SAID AUXILIARY DRIVE IS DEACTIVATED AND SAID AUXILIARY BRAKE IS ACTUATED TO STOP THE NEEDLE AT THE DESIRED POSITION.