Method and system for controlling draw tension on thread in a sewing system

Abstract

A method of controlling draw tension on thread wrapped around a bobbin that is mounted operatively on a case for movement relative to the case around an axis. The method includes the steps of: predetermining a desired thread draw tension to be achieved with the bobbin operatively mounted on a case using a predetermined mounting process; and, before operatively mounting the bobbin on the case, selectively controlling the at least one parameter of at least one of the thread and bobbin in a correlative manner to the desired thread draw tension with the bobbin operatively mounted on a case using the predetermined mounting process.

1 . A method of controlling draw tension on thread wrapped around a bobbin that is mounted operatively on a case for movement relative to the case around an axis, the method comprising the steps of: 
 predetermining a desired thread draw tension to be achieved with the bobbin operatively mounted on a case using a predetermined mounting process; and    before operatively mounting the bobbin on the case, selectively controlling at least one parameter of at least one of the thread and bobbin in a correlative manner to the desired thread draw tension.    
     
     
         2 . The method of controlling draw tension on thread according to  claim 1  wherein the step of controlling the at least one parameter comprises controlling thread tack.  
     
     
         3 . The method of controlling draw tension on thread according to  claim 1  wherein the step of controlling the at least one parameter comprises controlling thread gauge.  
     
     
         4 . The method of controlling draw tension on thread according to  claim 1  wherein the step of controlling the at least one parameter comprises controlling material defining the thread.  
     
     
         5 . The method of controlling draw tension on thread according to  claim 1  wherein the step of controlling the at least one parameter comprises controlling thread shape.  
     
     
         6 . The method of controlling draw tension on thread according to  claim 1  wherein the thread comprises a plurality of fibers and the step of controlling the at least one parameter comprises controlling structural interaction of the fibers defining the thread.  
     
     
         7 . The method of controlling draw tension on thread according to  claim 1  wherein the step of controlling the at least one parameter comprises defining the bobbin so as to control a magnetic interaction of the bobbin and case that resists rotation of the bobbin relative to the case with the bobbin operatively mounted on the case.  
     
     
         8 . The method of controlling draw tension on thread according to  claim 7  wherein the step of defining the bobbin comprises controlling parameters of a metallic component on the bobbin to magnetically interact with an element on the case.  
     
     
         9 . The method of controlling draw tension on thread according to  claim 7  wherein the step of defining the bobbin comprises controlling parameters of a magnetic element on the bobbin to magnetically interact with at least one of (a) a metallic element and (b) a magnetic element on the case.  
     
     
         10 . The method of controlling draw tension on thread according to  claim 1  wherein the step of controlling the at least one parameter comprises defining the bobbin so as to control frictional interaction of the bobbin and case that resists rotation of the bobbin relative to the case with the bobbin operatively mounted on the case.  
     
     
         11 . The method of controlling draw tension on thread according to  claim 10  wherein the step of defining the bobbin comprises selecting a material defining at least a part of the bobbin.  
     
     
         12 . The method of controlling draw tension on thread according to  claim 10  wherein the step of defining the bobbin comprises providing a flexible component on the bobbin that is biasably urged against the case with the bobbin operatively mounted on the case.  
     
     
         13 . The method of controlling draw tension on thread according to  claim 12  wherein the step of defining the bobbin comprises providing a surface that produces a frictional resistance to rotation when borne against by a flexible component on the case with the bobbin operatively mounted on the case.  
     
     
         14 . The method of controlling draw tension on thread according to  claim 1  wherein the step of controlling the at least one parameter comprises controlling the configuration of the bobbin.  
     
     
         15 . The method of controlling draw tension on thread according to  claim 1  wherein thread is wrapped around the bobbin with a wrapping pattern and the step of controlling the at least one parameter comprises controlling the wrapping pattern.  
     
     
         16 . The method of controlling draw tension on thread according to  claim 1  wherein thread is wrapped around the bobbin with a wrapping tension and the step of controlling the at least one parameter comprises controlling the wrapping tension.  
     
     
         17 . A method of controlling draw tension on thread wrapped around a bobbin and mounted operatively on a case for movement relative to the case around an axis, the method comprising the steps of: 
 providing a first bobbin with a supply of thread wrapped around the first bobbin so that with the first bobbin operatively mounted on a first case using a predetermined mounting process, a first thread draw tension results;    providing a second bobbin with a supply of thread wrapped around the second bobbin so that with the second bobbin operatively mounted on the first case using the predetermined mounting process, a second thread draw tension different than the first thread draw tension results;    choosing a desired thread draw tension by selecting to operatively mount to the first case one of the first and second bobbins; and    operatively mounting the one of the first and second bobbins to the first case.    
     
     
         18 . The method of controlling draw tension on thread according to  claim 17  further comprising the step of predetermining approximately first and second magnitudes of thread draw tension resulting with each of the first and second bobbins operatively mounted on the first case using the predetermined mounting process, and identifying the first and second magnitudes to facilitate selection by a user of one of the first and second bobbins for use.  
     
     
         19 . In combination: 
 a first bobbin having a supply of a first thread wrapped around the first bobbin so that with the first bobbin operatively mounted upon a case having a first construction using a predetermined mounting process, a thread draw tension with a first magnitude results; and    a second bobbin having a supply of a second thread wrapped around the second bobbin so that with the second bobbin operatively mounted upon a case having the first construction using a predetermined mounting process, a thread draw tension, with a magnitude of predetermined tension predetermined to be greater or less than the first magnitude, results,    whereby the first and second bobbins with their respective thread supplies can be selectively operatively mounted upon a case having the first construction to select greater or lesser thread draw tension.    
     
     
         20 . The combination according to  claim 19  further in combination with a first case having the first construction upon which the first and second bobbins can be interchangeably operably mounted.  
     
     
         21 . The combination according to  claim 19  wherein a difference between a thread draw tension resulting from the mounting of the first and second bobbins with their respective thread supplies to a case having the first construction is attributable to at least a difference in tack on the first and second threads.  
     
     
         22 . The combination according to  claim 19  wherein a difference between a thread draw tension resulting from the mounting of the first and second bobbins with their respective thread supplies to a case having the first construction is attributable to at least a difference in gauge of the first and second threads.  
     
     
         23 . The combination according to  claim 19  wherein a difference between a thread draw tension resulting from the mounting of the first and second bobbins with their respective thread supplies to a case having the first construction is attributable to at least a difference in material defining the first and second threads.  
     
     
         24 . The combination according to  claim 19  wherein a difference between a thread draw tension resulting from the mounting of the first and second bobbins with their respective thread supplies to a case having the first construction is attributable to at least a difference in shape of the first and second threads.  
     
     
         25 . The combination according to  claim 19  wherein the first and second threads are each defined by a plurality of fibers and a difference between a thread draw tension resulting from the mounting of the first and second bobbins with their respective thread supplies to a case having the first construction is attributable to at least a difference in structural interaction of fibers defining the first and second threads.  
     
     
         26 . The combination according to  claim 19  wherein a difference between a thread draw tension resulting from the mounting of the first and second bobbins with their respective thread supplies to a case having the first construction is attributable to at least a difference in magnetic interaction between a case having the first construction and the first and second bobbins.  
     
     
         27 . The combination according to  claim 19  wherein a difference between a thread draw tension resulting from the mounting of the first and second bobbins with their respective thread supplies to a case having the first construction is attributable to at least a difference in a frictional interaction between a case having the first construction and the first and second bobbins.  
     
     
         28 . The combination according to  claim 19  wherein a difference between a thread draw tension resulting from the mounting of the first and second bobbins with their respective thread supplies to a case having the first construction is attributable to at least a difference in configuration of the first and second bobbins.  
     
     
         29 . The combination according to  claim 19  wherein a difference between a thread draw tension resulting from the mounting of the first and second bobbins with their respective thread supplies to a case having the first construction is attributable to at least a difference in wrapping pattern of the first and second threads around the first and second bobbins.  
     
     
         30 . The combination according to  claim 19  wherein a difference between a thread draw tension resulting from the mounting of the first and second bobbins with their respective thread supplies to a case having the first construction is attributable to at least a difference in a wrapping tension for the first and second threads around the first and second bobbins.  
     
     
         31 . The combination according to  claim 19  wherein the first bobbin has a first flange with a first peripheral edge and the second bobbin has a second flange with a second peripheral edge each of which edges faces a radially inwardly facing surface on a case having the first construction to which the first and second bobbins are operatively mounted, and a difference between a thread draw tension resulting from the mounting of the first and second bobbins with their respective thread supplies to a case having the first construction is attributable to at least a difference in interaction of the first and second peripheral edges with a radially inwardly facing surface on a case having the first construction to which the first and second bobbins are operatively mounted.  
     
     
         32 . In combination: 
 a case having a radially inwardly facing surface extending around a space; and    a bobbin having an axis and a first axially facing flange with a peripheral edge facing the radially inwardly facing case surface,    wherein the case and bobbin are configured so that the peripheral edge does not contact the radially inwardly facing surface of the case around the entire peripheral edge.    
     
     
         33 . The combination according to  claim 32  wherein the case and bobbin are configured so that the peripheral edge of the flange does not contact the radially inwardly facing surface of the case.