Roller for hot rolling of wire rods and the like, and wire-rod and the like, hot-rolling machine provided with said roller

Abstract

A wire-rod and the like, hot-rolling machine wherein the two rollers are fitted on respective frustoconical end portions of as many counter-rotating supporting shafts, via interposition of corresponding centering and coupling bushings having a frustoconical internal profile, each of which is fitted on the end portion of a respective supporting shaft, between the supporting shaft and the corresponding roller, and is structured so as to mesh on the supporting shaft so as to be angularly integral to said supporting shaft, and so as to be inserted/wedged between the supporting shaft and the roller thus to center the roller on the supporting shaft and moreover make the roller angularly integral to the body of the supporting shaft. Each centering and coupling bushing is provided with an annular flange having an eccentric lobe-shaped profile and which cantilevered projects from the outer surface of the bushing, at one of the two mouths of the central through hole of the roller, and is designed to engage a corresponding annular groove with eccentric lobe-shaped profile which is formed on the body of the roller at the mouth of the roller central through hole, and has a shape complementary to that of the annular flange.

1 . Wire-rod and the like, hot-rolling machine which is adapted to hot-roll a wire-rod or the like moving forward along a pre-established feeding path, and which comprises:
 two counter-rotating supporting shafts which are arranged on opposite sides of the wire-rod feeding path, with respective longitudinal axes parallel to and facing each other and locally substantially perpendicular to the wire-rod feeding path, so as to arrange respective end portions in a substantially specular position on opposite sides of the wire-rod feeding path;   two rollers which are provided with a central through hole and are each fitted onto a respective supporting shaft, at the end portion of said supporting shaft; and   two centering and coupling bushings, each of which is fitted on the end portion of a respective supporting shaft, between the supporting shaft and the corresponding roller, and is structured so as to mesh on the supporting shaft to be angularly integral to said supporting shaft, and so as to be inserted/wedged between the supporting shaft and the roller, thus to center the roller on the supporting shaft and also to make the roller angularly integral to the body of the supporting shaft;   wherein each centering and coupling bushing is provided with an annular flange having eccentric lobe-shaped profile and which cantilevered projects from the outer surface of the bushing at one of the two mouths of the central through hole of the roller, and wherein each roller has, on the base facing the annular flange of the bushing, a corresponding annular groove which is formed on the body of the roller so as to surround the mouth of the central through hole of the roller, and has an eccentric lobe-shaped profile which is complementary in shape to that of the annular flange of the centering and coupling bushing so as to be engaged by the annular flange of said bushing.   
     
     
         2 . Machine according to  claim 1 , wherein the profile of the outer peripheral edge of the annular flange of the centering and coupling bushing is defined by a closed curved line that has a variable radius of curvature which, for one or more stretches, is eccentric with respect to the longitudinal axis of the bushing. 
     
     
         3 . Machine according to  claim 1 , wherein the profile of the outer peripheral edge of the annular groove of the roller is defined by a closed curved line that has a variable radius of curvature which, for one or more stretches, is eccentric with respect to the longitudinal axis of the roller. 
     
     
         4 . Machine according to  claim 3 , wherein the profile of the outer peripheral edge of the annular groove is substantially identical to the profile of the outer peripheral edge of the annular flange of the centering and coupling bushing. 
     
     
         5 . Machine according to  claim 1 , wherein the end portions of the two supporting shafts have a substantially frustoconical profile, and in that the two centering and coupling bushings present on the inside a frustoconical profile. 
     
     
         6 . Machine according to  claim 1 , wherein the annular flange of the centering and coupling bushing is shaped/profiled so as to have its bary center located on the longitudinal axis of the centering and coupling bushing. 
     
     
         7 . Machine according to  claim 1 , wherein the annular groove of the roller is preferably shaped/profiled so as to have its bary center located on the longitudinal axis of the roller. 
     
     
         8 . Machine according to  claim 1 , wherein the annular flange of the centering and coupling bushing and the annular groove of the roller are substantially elliptical in shape. 
     
     
         9 . Machine according to  claim 1 , further comprising an external supporting casing which is located against the wire-rod feeding path; the two supporting shafts being mounted in an axially rotatable manner on the supporting casing so as to cantilevered project from the supporting casing in substantially specular position, on opposite sides of the wire-rod feeding path, thus to arrange the respective end portions in a substantially specular position on opposite sides of the wire-rod feeding path. 
     
     
         10 . Machine according to  claim 9 , further comprising a gear train which is housed within the supporting casing and is structured so as to connect the two supporting shafts to a same driving motor, so as to allow said motor to drive the two supporting shafts simultaneously in rotation about their respective longitudinal axes in mutually opposite directions, substantially with identical angular velocities. 
     
     
         11 . Machine according to  claim 1 , further comprising, for each centering and coupling bushing, a respective removable blocking device which is structured so as to withhold the centering and coupling bushing stably fitted/inserted on the end portion of the supporting shaft, between the supporting shaft and the roller, with the annular flange of the bushing inserted/fitted in the annular groove of the roller. 
     
     
         12 . Machine according to  claim 11 , wherein the removable blocking device comprises a lock nut which is screwed directly on the distal end of the supporting shaft, and elastic means which are fitted on the distal end of the supporting shaft so as to be interposed between the body of the lock nut and the centering and coupling bushing, thus to press and withhold the centering and coupling bushing stably in abutment against the roller. 
     
     
         13 . Machine according to  claim 1 , wherein each roller consists of a substantially cylindrical-shaped, monolithic block of tungsten carbide which is provided with a central through hole with a diameter such as to allow the fitting of the monolithic block of tungsten carbide on the end portion of the supporting shaft. 
     
     
         14 . Roller for hot rolling of wire rods and the like, comprising a substantially cylindrical-shaped, monolithic block of high-resistance material which is provided with a central through hole designed to allow the fitting of the monolithic block of high-resistance material on a supporting shaft; wherein said monolithic block of high-resistance material has, on one of its two bases, an annular groove which is formed on the body of the monolithic block of high-resistance material so as to surround the mouth of the central through hole, and has an eccentric lobe-shaped profile. 
     
     
         15 . Roller according to  claim 14 , wherein the profile of the outer peripheral edge of the annular groove of the monolithic block of high-resistance material is defined by a closed curved line having a variable radius of curvature which, for one or more stretches, is eccentric with respect to the longitudinal axis of the monolithic block of high-resistance material. 
     
     
         16 . Roller according to  claim 14 , wherein the annular groove with eccentric lobe-shaped profile is substantially elliptical in shape. 
     
     
         17 . Roller according to  claim 16 , wherein the two foci of the ellipse are located, in specular position, on opposite sides of the longitudinal axis of the monolithic block of high-resistance material. 
     
     
         18 . Roller according to  claim 14 , wherein the monolithic block of high-resistance material is a substantially cylindrical-shaped, monolithic block of tungsten carbide.