Apparatus and method for carrying out working on a sheet

Abstract

An apparatus and a related method for carrying out working on the perimeter of a sheet having a first lateral surface an opposing second lateral surface and a perimeter edge, comprising multi-tool working heads and sliding constraint members that can be selectively activated to stabilize the working.

1 . An apparatus for working the perimeter of at least one sheet element comprising two parallel and opposing surfaces, said apparatus comprising means for exercising a relative movement between said sheet elements and at least one working head, said working head comprising at least two spindle units on which one or more tools are mounted in a direction for working the perimeter of said at least one sheet element, said working head comprises a plurality of stabilization units each having first sliding constraint members and opposing second sliding constraint members, and said stabilization units are selectively and independently drivable to bring at least some sliding constraint members from a deactivation condition to an activation condition in interaction with said sheet elements, and vice versa. 
     
     
         2 . The apparatus as in  claim 1 , wherein at least one stabilization unit is associated and cooperates with a respective spindle unit. 
     
     
         3 . The apparatus as in  claim 1 , wherein the interaction of at least some sliding constraint members with said sheet elements is exerted through a physical contact. 
     
     
         4 . The apparatus as in  claim 1 , wherein the interaction of at least some sliding constraint members with said sheet elements is exerted through a pressure exerted by a fluid. 
     
     
         5 . The apparatus as in  claim 1 , wherein an axis of rotation of at least one working head is chosen so as to be in a barycentric position with respect to the distribution of the rotating masses. 
     
     
         6 . The apparatus as in  claim 1 , wherein at least one of said working heads comprises means for selectively moving, in a manner independent of each other, at least one stabilization unit with respect to a reference which is integral with said working head. 
     
     
         7 . The apparatus as in  claim 6 , wherein said movement of at least one stabilization unit consists in a rotation around the axis of said spindle unit. 
     
     
         8 . The apparatus as in  claim 1 , wherein said at least one working head comprises means for moving at least some spindle units in the direction independently of each other. 
     
     
         9 . The apparatus as in  claim 1 , wherein said at least one working head comprises means for moving at least one spindle unit in the direction in a manner that depends on the movement of another spindle unit. 
     
     
         10 . The apparatus as in  claim 1 , wherein said at least one working head comprises at least one spindle unit in which the position in the direction remains fixed. 
     
     
         11 . The apparatus as in  claim 1 , wherein said at least one working head comprises selectively activated jets of fluid for the lubrication and cooling of the working. 
     
     
         12 . The apparatus as in  claim 1 , wherein the number of working heads is chosen preferably equal to two. 
     
     
         13 . The apparatus as in  claim 1 , comprising retractable holding units, lower support means and lateral support means, at least some of which can be excluded when the working tools pass. 
     
     
         14 . A method for carrying out perimeter working of sheet elements, which comprise first lateral surfaces, opposing second lateral surfaces and perimeters subject to working, comprising:
 a step of transporting said sheet elements to be worked in the work zone of an apparatus configured for the peripheral working of said sheet elements;   a step of hooking said sheet elements to holding means;   a step of acquiring the position of said sheet elements;   a constraint step, in which first and second sliding constraint members of a plurality of stabilization units associated with at least one working head are selectively brought to a condition of interaction with said sheet element,   a working step, in which at least one working head, each comprising at least two spindle units on which tools for working the perimeter are mounted, carries a succession of workings along said perimeters;   a step of transporting said sheet elements toward a subsequent station, wherein during working said plurality of stabilization units are selectively brought to a condition of sliding interaction with said sheet element when they are inside the perimeter, and to an inactive condition when they are outside of said perimeter.   
     
     
         15 . The method as in  claim 14 , wherein said interaction consists in the physical contact between said constraint members and said sheet element. 
     
     
         16 . The method as in  claim 14 , wherein during the working of said perimeter said stabilization units are moved in a reference which is integral with said working head in order to guarantee that said stabilization units are always within the perimeter of said sheet element. 
     
     
         17 . The method as in  claim 14 , wherein during said working step said spindle units are moved relative to the sheet element keeping each tool always engaged on said sheet element. 
     
     
         18 . The method as in  claim 14 , wherein during said working step each rolling element of the stabilization units is moved so that the corresponding rolling plane of each rolling element is always parallel to the direction of feed of the tool with which it is associated. 
     
     
         19 . The method as in  claim 14 , comprising a step in which at least some spindle units are moved to select the work tool or to centre said tool with respect to the thickness of the sheet element.