US 4,714,037 AGranted

Needle looper assembly for non-threaded needle lockstitching

AssigneeThe Singer Company

InventorsRalph E. Johnson, Donald Rodda

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Abstract

A needle looper assembly for a lockstitch sewing machine wherein the upper thread is retrieved by a sewing needle extending through a work material, which sewing needle has an extensible hook portion for catching an upper thread and drawing the same down through the work material to a looptaker in the bed of the sewing machine. The needle looper assembly is supported on the end of a lever pivotally carried in the sewing machine bed to extend transversely thereof. The lever has the needle looper assembly attached to one end thereof, and may be actuated by a cam so as to drive the needle looper assembly to an elevated thread catching position or to a retracted thread releasing position. Retaining means are provided associated with the needle looper to permit an upper thread to be caught and held during passage through a work material and to be released when in a retracted position adjacent the looptaker.

Claims5

Dependent claims

A needle looper assembly for a lockstitch sewing machine having a frame of a total height and including a bed of uniform height less than 1/3 of said total height, a drive means supported within said frame, a looptaker driven by said drive means, said needle looper assembly being supported in said bed and being used to draw a loop of upper thread down through a work material supported on said bed to said looptaker for concatentation with a lower thread;

said needle looper assembly comprising:
a lever pivotally carried within said bed, a needle rigidly clamped to one end of said lever substantially normal thereto, a means associated with said needle for selectively retaining said upper thread;
means driven by said drive means for oscillating said lever to urge said needle to an elevated position through said work material and to a retracted position adjacent said looptaker;
and, means supported within said bed for actuating said retaining means for receiving said upper thread when extended through said work material, for retaining said upper thread when traveling through said work material to said retracted position adjacent said looptaker, and for releasing said upper thread to said looptaker when retracted to said position adjacent said looptaker.

1 more element

A needle looper assembly for a lockstitch sewing machine having a frame of a total height and including a bed of uniform height less than 1/3 of said total height, a drive means supported within said frame, a looptaker driven by said drive means, said needle looper assembly being supported in said bed and being used to draw a loop of upper thread down through a work material to said looptaker for concatenation with a lower thread;

said needle looper assembly comprising:
a lever pivotably carried within said bed, a cam follower affixed to said lever, a needle rigidly clamped to one end of said lever substantially normal thereto, a means associated with said needle for selectively retaining said upper thread;
a cam supported in said frame and driven by said drive means, said cam having a track therein followed by said cam follower of said lever for urging said needle to an elevated position through said work material and to a retracted position adjacent said looptaker;
and, means supported by said bed for actuating said retaining means for receiving an upper thread when extended to said elevated position through said work material, for retaining said upper thread when traveling through said work material to said retracted position adjacent said looptaker, and for releasing said upper thread to said looptaker when retracted to a position adjacent said looptaker.

1 more element

Dependencies are inferred from the claim text.