Method and apparatus for false twisting textile yarns and product obtained thereby

Claim 2

A process for texturing thermoplastic threads comprising the steps of rotating an annular frictional surface about its central axis, heating a length of thermoplastic thread, passing a running length of the heated thread into contact with the rotating annular surface to twist the thread about its longitudinal axis, passing the thread out of contact with the annular surface, intermittently cooling the thread while out of contact with the annular frictional surface, and again passing the thread into contact with the rotating annular surface to twist the thread about its longitudinal axis, thereby subjecting the thread to at least two consecutive operations of false twist.

Claim 3

Apparatus for frictionally false twisting a running length of thread comprising means defining an annular frictional surface, means for rotating the annular surface about its central axis, and means for guiding the thread into engagement with the annular frictional surface at at least two spaced points to impart consecutive twist to the thread about its longitudinal axis, said guiding means comprising plural guide arms supported on one side of said annular frictional surface in angular staggered relation with respect to each other and means for moving said guide arms toward and away from said annular frictional surface to direct thread into and out of engagement therewith.

Claim 4

Apparatus for frictionally false twisting a running length of thread comprising means defining an annular frictional surface, means for rotating the annular surface about its central axis, and means for guiding the thread into engagement with the annular frictional surface at at least two spaced points to impart consecutive twist to the thread about its longitudinal axis, said guiding means comprising plural guide arms supported on one side of said annular frictional surface in angular staggered relation with respect to each other and means for moving said guide arms toward and away from said annular frictional surface to direct thread into and out of engagement therewith.

Claim 5

Apparatus as defined in claim 2 wherein said means for moving said guide arms comprises a hollow tube, and end portions of said guide arms being slidable along said hollow tube to telescopically extend and retract the guide arms for movement into and out of the space bounded by said annular frictional surface.

Claim 6

Apparatus as defined in claim 2 wherein said guide means include at least three guide arms, eyelets on each of said guide arms for engaging and guiding thread, and said moving means including means for positioning some of the eyelets of said guide arms on one side of the space bounded by said annular frictional surface and some of the eyelets on the other side of said space to define paths of multiple passage of the thread through the bounded space.

Claim 7

A process for texturing threads comprising the steps of rotating an annular frictional surface about its central axis, heating a length of thermoplastic thread, passing a running length of the heated thread into the space bounded by the annular surface and reversing the direction of travel of the thread through the space to contact the thread with the rotating surface at least twice to twist the thread about its longitudinal axis.

Claim 8

A process for texturing threads comprising the steps of rotating an annular frictional surface about its central axis, heating a length of thermoplastic thread, passing a running length of the heated thread into the space bounded by the annular surface and reversing the direction of travel of the thread through the space to contact the thread with the rotating surface at least twice to twist the thread about its longitudinal axis.

Claim 9

A process as defined in claim 5 wherein the direction of the travel of the thread is reversed by passing the thread in opposite directions relative to the central axis of the rotating surface at least 2n times, n being a whole number.

Claim 10

Apparatus for false twisting a running length of thread comprising means defining an annular frictional surface, means for rotating the surface about its central axis, and means for guiding the thread through the space bounded by the annular surface in reversing directions to contact the thread with the frictional surface at at least two spaced points to impart twist thereto.

Claim 11

Apparatus for false twisting a running length of thread comprising means defining an annular frictional surface, means for rotating the surface about its central axis, and means for guiding the thread through the space bounded by the annular surface in reversing directions to contact the thread with the frictional surface at at least two spaced points to impart twist thereto.

Claim 12

Apparatus as defined in claim 7 wherein said means defining said annular surface comprises a cup-shaped member, the internal side portions of said member being comprised of a member having a high coefficient of friction.