Metal spool

Abstract

The invention specifies a metal spool for receiving metallic winding material ( 5 ) in the form of a wire, which spool comprises two flanges ( 1, 2 ) in the form of circular disks, arranged parallel to one another and having the same diameter and an elongate core ( 3 ) connecting the flanges and having a circular cross section and smaller radial dimensions in comparison with the flanges ( 1, 2 ), the mid-axis of which core corresponds to the mid-axes of the flanges ( 1, 2 ). A winding space ( 4 ) for receiving the winding material ( 5 ), is delimited by the core ( 3 ) and the two flanges ( 1, 2 ). The dimensions of the winding space ( 4 ) in the direction of the mid-axis of the spool can be enlarged at an increased temperature. In addition, means are provided to bring the dimensions of the winding space ( 4 ) back to the initial position when the temperature returns to room temperature.

1 . A metal spoool for receving metallic winding material in the form of a wire, comprising: 
 two flanges in the form of circular disks, arranged parallel to one another, and    an elongate core connecting said flanges and having a circular cross section a smaller radial dimension in comparison with radial dimensions of the flanges, the mid-axis of said core corresponding to mid-axes of the flanges, a winding space for recieving the winding material being delimited by the core and the two flanges, said flanges and core arranged so that the distance between the flanges can alterd elastically by forces acting on them, wherein    the dimensions of the winding space in the direction of the mid-axis of the spool can enlarged at an increased temperature, in comparsion with and initial position at room temperature by forces which are brought about by different coefficients of thermal expansion of the winding material, on the one hand, and of the core of the spool, on the other hand, and    means for bringing the dimensions of the winding space back to the initial position when the temperature returns to room temperature.    
   
   
       2 . The spool as claimed in  claim 1 , wherein the enlarging of the dimensions of the winding space between room temperature and the increased temperature is equal to a length el in accordance with the following equation  
         el=l   o1 ×Δδ(α w −α c ),  
     where the variables: 
 l o1 =length of the core at room temperature  
 Δδ=difference between the room temperature and the increased temperature  
 α w =coefficient of thermal expansion of the material for the winding material  
 α c =coefficient of thermal expansion of the material for the core.  
 
   
   
       3 . The spool as claimed in  claim 2 , wherein the core is in the form of a tube, which is corrugated all the way round transversely with respect to its axis at least in one section of the tube.  
   
   
       4 . The spool as claimed in  claim 2 , wherein the core is attached fixedly to one flange of the spool and is connected to the other flange via a spring mechanism.  
   
   
       5 . The spool as claimed in  claim 2 , wherein the core comprises two tubes which are arranged concentrically with respect to one another and bear against one another and of which one is fixed to one flange and the other is fixed to the other flange and which are connected to one another by a spring mechanism which is effective in the axial direction.  
   
   
       6 . The spool as claimed in  claim 1 , wherein an intermediate flange is arranged in the winding space between the two flanges at least in the vicinity of one flange, which intermediate flange is mounted displaceably on the core and is connected to the flange in whose vicinity it is arranged via springs acting in the axial direction of the core.  
   
   
       7 . The spool as claimed in  claim 6 , wherein outwardly protruding bolts, which pass through holes in the associated flange, are attached to the intermediate flange in the axial direction of the core.  
   
   
       8 . A metal spool for receiving metallic winding material in the form of a wire, comprising: 
 two flanges in the form of circular disks arranged parallel to one another, and    an elongate core connecting said flanges and having a circular cross section and a smaller radial dimension in comparison with radial dimensions of the flanges, the mid-axis of said core corresponding to mid-axes of the flanges, a winding space for receiving the winding material being delimited by the core and the two flanges, wherein the core comprises a material which has a coefficient of thermal expansion which is at least approximately the same as the material for the winding material.    
   
   
       9 . The spool as claimed in  claim 1 , wherein the core is in the form of a tube, which is corrugated all the way round transversely with respect to its axis at least in one section of the tube.  
   
   
       10 . The spool as claimed in  claim 1 , wherein the core is attached fixedly to one flange of the spool and is connected to the other flange via a spring mechanism.  
   
   
       11 . The spool as claimed in  claim 1 , wherein the core comprises two tubes which are arranged concentrically with respect to one another and bear against one another and of which one is fixed to one flange and the other is fixed to the other flange and which are connected to one another by a spring mechanism which is effective in the axial direction.