Conveying roller, production method thereof and conveying apparatus

Abstract

A conveying roller pair disposed in a bleaching-fixing bath of a photographic printer is constituted of a flat roller and a projection roller. Plural roller pieces are fixed to a roller shaft of the projection roller. Plural projections are formed by coating molding on an outer peripheral surface of the roller piece. Each roller piece has a core with an approximately ring shape, and an elastic layer with plural projections. The core and the elastic layer are adhered through a primer layer. Accordingly, uniform adhesive strength is secured and slipping of the elastic layer on the core is prevented. Since the plural projections are arranged in a phase-coherent manner, contact condition and contact pressure between the sheet and the projection roller are kept constant. As a result, a skew of the sheet is prevented.

1 . A conveying roller comprising: 
 a roller shaft; and    plural cores fixed to said roller shaft, said cores and said roller shaft integrally rotating about a rotation center line of said roller shaft, an elastic layer having plural projections being formed by coating molding on an outer peripheral surface of each of said cores.    
     
     
         2 . A conveying roller according to  claim 1 , wherein said elastic layer is formed after forming a primer layer on each of said cores by coating a primer.  
     
     
         3 . A conveying roller according to  claim 2 , wherein a blasting is performed to a surface of each of said cores for increasing adhesive strength before forming said primer layer.  
     
     
         4 . A conveying roller according to  claim 1 , wherein said plural projections are aligned to form projection lines, which are in parallel to said rotation center line, said projection lines are arranged at a constant pitch in a circumferential direction.  
     
     
         5 . A conveying roller according to  claim 4 , wherein said plural projections are arranged in a zigzag by shifting said adjacent projection lines in the direction of said rotation center line.  
     
     
         6 . A conveying roller according to  claim 1 , wherein a fitting hole is formed through each of said cores along said rotation center line, each of said cores is attached to said roller shaft by inserting said roller shaft into said fitting hole.  
     
     
         7 . A conveying roller according to  claim 6 , wherein a fixing member is attached to said roller shaft for fixing each of said cores to said roller shaft.  
     
     
         8 . A conveying roller according to  claim 7 , wherein an engaging section, in which said fixing member is engaged, is formed in each of said cores for fixing each of said cores to said roller shaft.  
     
     
         9 . A method for producing a conveying roller comprising the steps of: 
 forming an elastic layer having plural projections by coating molding on an outer peripheral surface of each of plural cores; and    fixing said cores, each of which is formed with said elastic layer, to a roller shaft such that said cores and said roller shaft integrally rotate about a rotation center line of said roller shaft.    
     
     
         10 . A method according to  claim 9 , wherein said coating molding of said elastic layer is performed by setting said core as a core in a mold, and filling an elastic material in a cavity formed between said core and said mold.  
     
     
         11 . A method according to  claim 10 , wherein said coating molding of said elastic layer is performed after a primer layer is formed on each of said cores by coating a primer.  
     
     
         12 . A method according to  claim 11 , wherein a blasting is performed to a surface of each of said cores for increasing adhesive strength before forming said primer layer.  
     
     
         13 . A method according to  claim 10 , wherein said core is set in said mold in a predetermined position in a circumferential direction.  
     
     
         14 . A method according to  claim 13 , wherein said plural projections are aligned to form projection lines, which are in parallel to said rotation center line, said projection lines are arranged at a constant pitch in said circumferential direction.  
     
     
         15 . A method according to  claim 14 , wherein said plural projections are arranged in a zigzag by shifting said adjacent projection lines in the direction of said rotation center line.  
     
     
         16 . A method according to  claim 9 , wherein a fitting hole is formed through each of said cores along said rotation center line, each of said cores is attached to said roller shaft by inserting said roller shaft into said fitting hole.  
     
     
         17 . A method according to  claim 16 , wherein a fixing member is attached to said roller shaft for fixing each of said cores to said roller shaft.  
     
     
         18 . A method according to  claim 17 , wherein an engaging section, in which said fixing member is engaged, is formed in each of said cores for fixing said cores to said roller shaft.  
     
     
         19 . A method according to  claim 9 , wherein said core is formed of a thermoplastic resin material, a thermosetting resin material or a metal material.  
     
     
         20 . A method according to  claim 9 , wherein said elastic layer is formed of a vulcanized rubber or a thermoplastic elastomer.  
     
     
         21 . A method according to  claim 20 , wherein a hardness of said elastic layer is approximately 50 degrees.  
     
     
         22 . A conveying apparatus comprising: 
 a conveying roller pair including: 
 a conveying roller formed such that plural cores are attached to a roller shaft, said cores and said roller shaft integrally rotating about a rotation center line of said roller shaft, an elastic layer having plural projections being formed by coating molding on an outer peripheral surface of each of said cores; and  
 a flat roller used in a pair with said conveying roller for nipping and conveying a sheet.  
   
     
     
         23 . A conveying apparatus according to  claim 22 , wherein said elastic layer is formed after forming a primer layer on each of said cores by coating a primer.  
     
     
         24 . A conveying apparatus according to  claim 22 , wherein said projections in a nip area, where said sheet is nipped, are deformed so that said projections outside said nip area in a width direction of said conveying roller contact said flat roller when said conveying roller and said flat roller nip said sheet.  
     
     
         25 . A conveying apparatus according to  claim 24 , wherein a hardness of said elastic layer is approximately 50 degrees.  
     
     
         26 . A conveying apparatus according to  claim 22 , wherein said sheet is a photosensitive material.  
     
     
         27 . A conveying apparatus according to  claim 22 , wherein said conveying roller pair is disposed in a storage tank in which a processing solution is stored, and said elastic layer, said cores and said primer layer are chemical-resistant to said processing solution.