US 11,952,692 B2
Stitch-forming tool assembly for a sewing system and sewing system having such an assembly
Harald Kallenbach, Heltersberg (DE); Berthold Becker, Rimbach (DE); and Stefan Samstag, Lorsch (DE)
Assigned to PFAFF Industriesysteme und Maschinen GmbH, Kaiserslautern (DE)
Appl. No. 17/785,442
Filed by PFAFF Industriesysteme und Maschinen GmbH, Kaiserslautern (DE)
PCT Filed Dec. 7, 2020, PCT No. PCT/EP2020/084822
§ 371(c)(1), (2) Date Jun. 15, 2022,
PCT Pub. No. WO2021/122086, PCT Pub. Date Jun. 24, 2021.
Claims priority of application No. 10 2019 219 814.7 (DE), filed on Dec. 17, 2019.
Prior Publication US 2023/0013197 A1, Jan. 19, 2023
Int. Cl. D05B 57/02 (2006.01); D05B 57/32 (2006.01)
CPC D05B 57/02 (2013.01) [D05B 57/32 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A stitch-forming tool assembly (6) for a sewing system (1) for producing a double chain stitch seam (7),
having a sewing needle (8) which can be driven up and down in a needle stitching direction (z) perpendicular to a material to be sewn and is designed to guide a needle thread (10),
having a looper (12) designed to guide a looper thread (18) and for oscillating movement in an oscillating movement plane (xz) which is spanned
by the needle stitching direction (z) and
by a sewing direction (x) along the double chain stitch seam (7),
wherein a path of movement of the looper (12) lies completely in the oscillating movement plane (xz) during an entire double chain stitch,
wherein a central longitudinal axis (19) of the sewing needle (8) is spaced from a needle point (20) of the sewing needle (8) and
wherein, when the looper (12) passes the needle point (20) during stitch formation, the central longitudinal axis (19) lies between the needle point (20) and the looper (12).