Pattern mechanism

•The shogging movement is initiated by varying the radius of 

the continuously turning pattern shaft either in the form of 

different heights of pattern links which poses over a pattern 

drum attached to

 the shaft or in the form of carefully shaped solid metal 

 circular cams, termed pattern wheels,

attached to it. An increase in height one link to the next 

produces a thrust against the end of the

 guide by shogging it positively into the m/c a decrease will 

produce a negative shog towards the pattern  shaft as the

 

  result of the action of a return spring. A constant 

height will produce no shog if 

 

the guide bar will continued to swing through the same 

needle space. The periphery of the pattern

wheel or chain track is scanned by a roller which is link by a flexible jointed push-rod to the end of 

the guide bar. The under side of the rod near the roller is supported on the side with moves freely 

or a metal surface as shogging occurs.