A flat part for a knitting machine and a knitting machine comprising such flat part

Abstract

A flat part for a knitting machine includes a main flat body and a pair of springs protruding on opposed sides of the main flat body and resting against opposed surfaces of a respective groove in the needle-holding cylinder of a knitting machine. Each spring, when the flat part is inserted into the groove, pushes against the respective surface of the groove, so as to make it easier for the flat part to oscillate in the groove and/or to stabilize the positioning of the flat part in the groove.

1 . A flat part for a knitting machine, wherein the knitting machine comprises a plurality of grooves ( 4 ), each housing one or more flat parts moving in translation and/or oscillating in said grooves ( 4 ), wherein the flat part comprises:
 a main flat body ( 100 ) and a pair of springs ( 20 ) protruding on opposed sides of the main flat body ( 100 ) and resting against opposed surfaces ( 4   a ) of the respective groove ( 4 );   wherein each spring ( 20 ), when the flat part is inserted into the groove ( 4 ), pushes against the respective surface of the groove ( 4 ), so as to optimize oscillation of the flat part in said groove ( 4 ) and/or to stabilize the flat part in said groove ( 4 ).   
     
     
         2 . The flat part according to  claim 1 , wherein opposed lateral portions of the springs ( 20 ), configured for contacting the surfaces ( 4   a ) of the groove ( 4 ), are located along an axis (Y-Y) basically orthogonal to the main flat body ( 100 ). 
     
     
         3 . The flat part according to  claim 1 , wherein each of the springs ( 20 ) comprises a bow-shaped plate whose convexity points outside the main flat body ( 100 ), wherein the bow-shaped plate is elastically deformable. 
     
     
         4 . The flat part according to  claim 3 , wherein the bow-shaped plate exhibits only one proximal end ( 21 ) joined to the main flat body ( 100 ). 
     
     
         5 . The flat part according to  claim 4 , wherein the main flat body ( 100 ) exhibits a through opening ( 23 ) and the springs ( 20 ) are located at said through opening ( 23 ). 
     
     
         6 . The flat part according to  claim 5 , wherein the proximal end ( 21 ) is joined to at least one edge of the through opening ( 23 ). 
     
     
         7 . The flat part according to  claim 5 , comprising a thin wall ( 102 ) thinner than a thickness of the main flat body ( 100 ), which is located in the through opening ( 23 ), wherein the proximal end ( 21 ) of each bow-shaped plate is joined to the thin wall ( 102 ). 
     
     
         8 . The flat part according to  claim 6 , wherein a distal end ( 22 ), opposed to the proximal end ( 21 ), of the bow-shaped plate is free. 
     
     
         9 . The flat part according to  claim 18 , wherein the proximal ends ( 21 ) and/or the distal ends ( 22 ) of each bow-shaped plate are basically located at a middle plane (P) of the main flat body ( 100 ). 
     
     
         10 . The flat part according to  claim 1 , wherein the springs ( 20 ) are symmetrical or basically symmetrical to a middle plane (P) of the main flat body ( 100 ). 
     
     
         11 . The flat part according to  claim 1 , wherein the springs ( 20 ) are configured for keeping the flat part on a median plane of the respective groove ( 4 ). 
     
     
         12 . The flat part according to  claim 1 , wherein only the springs ( 20 ) are configured for touching the opposed surfaces ( 4   a ) of the respective groove ( 4 ), while the main flat body ( 100 ) lies at a distance from said surfaces ( 4   a ). 
     
     
         13 . The flat part according to  claim 1 , wherein said flat part is chosen from the group comprising: a needle, a jack, a sub-needle, a selector ( 7 ), a pushing unit. 
     
     
         14 . A drive chain for a needle of a knitting machine, comprising at least one flat part in accordance with  claim 1 . 
     
     
         15 . A drive chain for a needle of a circular knitting machine, wherein the drive chain ( 5 ), once mounted to the circular knitting machine, is inserted into a respective longitudinal groove ( 4 ) of a needle-holding cylinder ( 2 ) of said machine, is located below a respective needle ( 3 ) and is operatively placed between the respective needle ( 3 ) and actuating cams (C) of said machine, said drive chain ( 5 ) comprising:
 a sub-needle ( 6 ) arranged below the needle ( 3 ) and engaged to the needle ( 3 ) so as to move axially in the respective longitudinal groove ( 4 ) together with said needle ( 3 ); wherein the sub-needle ( 6 ) comprises a moving butt ( 14 ) radially movable between an operating position, in which it is extracted from the needle-holding cylinder ( 2 ) so as to engage with respective first paths defined by first actuating cams ( 39 ) and cause the needle ( 3 ) to be activated, and a non-operating position, in which it is retracted in the needle-holding cylinder ( 2 ) so as not to engage with said first paths;   a selector ( 7 ) partly located below the sub-needle ( 6 ) and partly beside the sub-needle ( 6 ), wherein the selector ( 7 ) is configured for oscillating between an active position, in which it pushes the moving butt ( 14 ) to the operating position, and a rest position, in which it allows the moving butt ( 14 ) to get back to the non-operating position, wherein the selector ( 7 ) is axially decoupled from the sub-needle ( 6 ) and from the needle ( 3 ) so that the needle ( 3 ) and the sub-needle ( 6 ) are never pushed or pulled axially by said selector ( 7 ); wherein the selector ( 7 ) is a flat part in accordance with  claim 1 .   
     
     
         16 . A knitting machine comprising a plurality of drive chains according to  claim 15 . 
     
     
         17 . A circular knitting machine, comprising:
 a needle-holding cylinder ( 2 ) having a plurality of longitudinal grooves ( 4 ) arranged around a central axis (X-X) of the needle-holding cylinder ( 2 );   a plurality of needles ( 3 ), each being housed in a respective longitudinal groove ( 4 );   actuating cams (C) arranged around the needle-holding cylinder ( 2 ); wherein said needle-holding cylinder ( 2 ) is movable with respect to the actuating cams (C) around the central axis (X-X) for causing or allowing the movement of the needles ( 3 ) along the longitudinal grooves ( 4 ) so as to enable stitch formation by said needles ( 3 );   a drive chain ( 5 ) for each needle ( 3 ) inserted into the respective longitudinal groove ( 4 ), located below the respective needle ( 3 ) and operatively placed between the respective needle ( 3 ) and said actuating cams (C); wherein said drive chain ( 5 ) is in accordance with  claim 15 .   
     
     
         18 . The flat part according to  claim 1 , wherein the main flat body ( 100 ) exhibits a through opening ( 23 ) and the springs ( 20 ) are located at said through opening ( 23 ). 
     
     
         19 . A knitting machine comprising a plurality of drive chains according to  claim 14 . 
     
     
         20 . A circular knitting machine, comprising:
 a needle-holding cylinder ( 2 ) having a plurality of longitudinal grooves ( 4 ) arranged around a central axis (X-X) of the needle-holding cylinder ( 2 );   a plurality of needles ( 3 ), each being housed in a respective longitudinal groove ( 4 );   actuating cams (C) arranged around the needle-holding cylinder ( 2 ); wherein said needle-holding cylinder ( 2 ) is movable with respect to the actuating cams (C) around the central axis (X-X) for causing or allowing the movement of the needles ( 3 ) along the longitudinal grooves ( 4 ) so as to enable stitch formation by said needles ( 3 );   a drive chain ( 5 ) for each needle ( 3 ) inserted into the respective longitudinal groove ( 4 ), located below the respective needle ( 3 ) and operatively placed between the respective needle ( 3 ) and said actuating cams (C); wherein said drive chain ( 5 ) is in accordance with  claim 14 .