Method for the Positioning of Operative Cylinders on a Grinding Machine and Grinding Machine Which Implements This Method

Abstract

A method for positioning operative cylinders, for example of rolling-mills or paper-mills on a grinding machine, includes at least the following steps: A—positioning the transversal, longitudinal center-line plane of the cylinder in correspondence with a reference point situated between a movable piece-holder head and tailstock center of the machine; B—moving the piece-holder head and the tailstock center in the direction of the cylinder until there is a reciprocal coupling. The present invention relates also to a machine for implementing the above method.

The invention claimed is: 
     
         1 . A positioning method for operative cylinders, for example of rolling-mills or paper-mills, on a grinding machine the method comprising the following steps:
 a. positioning a transversal, longitudinal center-line plane of a cylinder in correspondence with a reference point situated between a movable piece-holder head and tailstock center of a grinding machine; and   b. moving said piece-holder head and said tailstock center towards a direction of said cylinder until there is a reciprocal coupling, for entraining and/or supporting the cylinder.   
     
     
         2 . The method according to  claim 1 , wherein said reference point is positioned equidistant from said piece-holder head and said tailstock centercentre. 
     
     
         3 . The method according to  claim 1 , wherein said moving in step b comprises moving said piece-holder head and said tailstock center of same entity, in a same direction and in opposite senses. 
     
     
         4 . The method according to  claim 1 , further comprising the following steps:
 preparing the cylinder to be ground;   positioning the transversal, longitudinal center-line plane of the cylinder in correspondence with the reference point situated between the moveable piece-holder head and the tailstock centre of the machine;   moving said piece-holder head and said tailstock center until coupled with said cylinder; and   positioning at least two supporting side lunettes ( 21 ,  22 ) of said cylinder at a same distance from said reference point.   
     
     
         5 . A grinding machine for operative cylinders, for example of rolling-mills or paper-mills, comprising:
 a base;   a piece-holder head; and   a tailstock center suitable for being coupled at opposite ends of a cylinder to be ground, in order to rotate said cylinder,   wherein said piece-holder head and said tailstock center are designed to be translated with respect to said base.   
     
     
         6 . The grinding machine according to  claim 5 , wherein said piece-holder head and said tailstock center are coupled with a moving system configured to allow their linear translation for their reciprocal approach or withdrawal. 
     
     
         7 . The grinding machine according to  claim 6 , wherein said moving system is configured to allow a movement of said piece-holder head and said tailstock center in a same direction, of a same entity and in opposite senses. 
     
     
         8 . The grinding machine according to  claim 6 , wherein said moving system comprises an endless screw coupled with the piece-holder head and tailstock center. 
     
     
         9 . The grinding machine according to  claim 6 , further comprising a central lunette for central contrast and at least two side lunettes for one or both of contrast or support of said cylinder, said central lunette being positioned in an equidistant position from said piece-holder head and said tailstock center. 
     
     
         10 . The grinding machine according to  claim 9 , wherein said moving system for the piece-holder head and the tailstock center is coupled with said side lunettes, for determining a reciprocal movement in a same direction, of a same entity and in opposite senses. 
     
     
         11 . The method according to  claim 4 , wherein said reference point coincides with a supporting lunette of said cylinder. 
     
     
         12 . The grinding machine according to  claim 8 , wherein said screw preferably is composed of a single piece and comprises two threaded parts having a discordant, helicoidal threading.