Coreless winding apparatus

Abstract

Disclosed is an apparatus for forming coreless paper rolls. The apparatus includes an expansible mandrel that can be used in conjunction with an existing rewinder. The mandrel is segmented, with the segments expanding when the mandrel is loaded into the rewinder. While in the rewinder, a web of material, such as the type used to form register receipt rolls, is wound upon the mandrel. After a sufficient amount of material has been taken up, the mandrel is removed from the rewinder. Upon removal, the segments contract whereby the cross section of the mandrel is reduced and the roll can be removed. The result is a coreless roll of material.

1 . A mandrel for use within a winding apparatus, the mandrel permitting the production of coreless rolls and comprising in combination: 
 a hexagonal support shaft having first and second ends, an axial recess formed within the first end, a spring mounted within the recess, two sets of locator balls positioned along the support shaft intermediate the first and second ends;    three arcuate shell segments each shell segment having first and second stepped ends, elongated side edges, and inner and outer surfaces, tapered pockets formed within the inner surface of each of the shell segments, the shell segments positioned upon the support shaft with the locator balls being positioned within the tapered pockets;    a stub shaft having an outer loading end and an inner end of a reduced diameter, the inner end being slidably positioned within the axial recess of the support shaft, the stub shaft having a compressed orientation wherein the spring of the axial recess is compressed and a decompressed orientation wherein the spring of the axial recess is decompressed, the compressed orientation being achieved when the mandrel is positioned within the winding apparatus;    a retainer cap secured over each of the ends of the support shaft and each of the stepped ends of the shell segments;    three lateral loading pins, each pin interconnecting the stub shaft to a corresponding arcuate shell segment, the pins functioning to translate the shell segments as the stub shaft is moved between the compressed and decompressed orientations and wherein with the stub shaft in the compressed orientation the locator balls are positioned within the tapered pockets so as to lift the shell segments from the support shaft and thereby enlarge the diameter of the mandrel and wherein when the stub shaft is in the decompressed orientation the locator balls are positioned within the tapered pockets so as to allow the elongated side edges of the shell segments to come together to form a continuous cylindrical surface and thereby reduce the diameter of the mandrel.    
   
   
       2 . A mandrel comprising: 
 a support shaft having first and second ends, bearings positioned along the support shaft intermediate the first and second ends;    shell segments having first and second ends, pockets formed within the shell segments, the shell segments positioned upon the support shaft with the bearings being positioned within the pockets;    a stub shaft being slidably positioned relative to the support shaft, the stub shaft having a compressed orientation and a decompressed orientation;    pins interconnecting the stub shaft to a corresponding shell segment, the pins functioning to translate the shell segments as the stub shaft is moved between the compressed and decompressed orientations and wherein with the stub shaft in the compressed orientation the bearings are positioned within the pockets so as to lift the shell segments from the support shaft and thereby enlarge the diameter of the mandrel and wherein when the stub shaft is in the decompressed orientation the bearings are positioned within the pockets so as to decrease the space between adjacent shell segments and thereby reduce the diameter of the mandrel.    
   
   
       3 . The mandrel as described in  claim 2  wherein three shell segments are included and each of the shell segments spans approximately 120 degrees.  
   
   
       4 . The mandrel as described in  claim 3  wherein when the stub shaft is in the decompressed orientation the three shell segments are brought together to form a continuous cylinder.  
   
   
       5 . The mandrel as described in  claim 2  wherein the support shaft includes an axial recess and the stub shaft is slidably positioned within the axial recess.  
   
   
       6 . The mandrel as described in  claim 5  wherein the stub shaft and the support shaft are interconnected by a spring that urges the stub shaft into the decompressed orientation.  
   
   
       7 . The mandrel as described in  claim 2  wherein the pockets of the shell segments are tapered and include a shallow region and a deep region, so that with the bearings in the shallow region the diameter of the mandrel is increased and with the bearings in the deep region the diameter of the mandrel is decreased.  
   
   
       8 . A mandrel comprising: 
 a support shaft having first and second ends, bearings positioned along the support shaft intermediate the first and second ends;    shell segments having first and second ends, pockets formed within the shell segments, the shell segments positioned upon the support shaft with the bearings being positioned within the pockets, the shell segments being laterally movable between first and second orientations;    wherein in the first orientation the bearings are positioned within the pockets so as to enlarge the diameter of the mandrel and wherein in the second orientation the bearings are positioned within the pockets so as to reduce the diameter of the mandrel.    
   
   
       9 . The mandrel as described in  claim 8  wherein a stub shaft is employed in positioning the shell segments in either the first or second orientations.  
   
   
       10 . The mandrel as described in  claim 9  wherein the stub shaft is slidably positioned relative to the support shaft.