Fluid-actuated cylinder and method for manufacturing it

Abstract

A fluid-actuated cylinder and a method for manufacturing it, including a head and a connecting tube to be coupled; coupling is obtained by compression of the two members along their axis, deforming the end of the tube by using, as a die for the deformation of the tube, a particular ring which is fitted on the head member and is coaxial thereto.

1 . A fluid-actuated cylinder comprising at least one head which is applied hermetically to the end of a tube which is folded inside an annular groove formed in said head, characterized in that it comprises a deformation ring which is arranged between said head and said folded end of said tube.  
     
     
         2 . The cylinder according to  claim 1 , characterized in that said deformation ring is fitted on said head at a tapering portion of the surface of the head.  
     
     
         3 . The cylinder according to  claim 1  or  2 , characterized in that said deformation ring comprises a convex chamfered internal surface which has its own radius of curvature.  
     
     
         4 . The cylinder according to one or more of the preceding claims, characterized in that said tapering portion comprises a radius of curvature which corresponds to the radius of curvature of said internal surface of said deformation ring.  
     
     
         5 . A method for manufacturing a fluid-actuated cylinder comprising at least one head and a tube to be coupled, characterized in that it comprises the steps of: 
 forming a groove in an outer cylindrical surface of said head proximate to the coupling region, applying a ring which comprises a chamfered internal surface, at a tapering portion, having a similar radiusing, which is formed on said outer surface of said head;    performing an axial compression between said head and said tube, making the end of said tube slide inside said groove, so that said end of said tube is deformed and compressed against said tapering portion of said head member, forcing said ring to maintain a forced arrangement between said head member and said connecting tube by elastic reaction.    
     
     
         6 . A device for the hermetic assembly of at least one head and a tube which are adapted to constitute a fluid-actuated cylinder, characterized in that it comprises a deformation ring which can be applied to said head at a tapering portion of said head in order to form a groove in which the end of said tube is deformed by axial compression of said tube and said head.