Roll stand with means for joining a web to another when unwound from rolls

Abstract

A roller stand incorporating a device adapted to join a running web of material being unwound from a first roll to a web of material of a second roll and comprising a roll-holding device including two unwinding stations, means to cut the running web, a mechanism to exert a braking force on the spindles supporting said first and second rolls, and means provided to transfer rotational motion of said roll-support spindles to said braking mechanism by means of free-wheel members, said members being arranged to control said braking mechanism selectively for application of braking force on the roll-support spindle that at the moment has the highest rotational speed.

What I claim is: 
     
       1. An improved roller stand comprising a frame, two unwinding stations, a first roll of a web of material, a first rotating spindle supporting said first roll, a second roll of a web of material, a second rotating spindle supporting said second roll, means for joining the web of material being unwound from said first roll to the leading end of the web of material of said second roll, means arranged to transversely cut said first web of material, and a braking mechanism supported by the frame of the roller stand to exert a braking force .[.an.]. .Iadd.on .Iaddend.said roll support spindles, the improvement comprising a roll-holding device, .Iadd.incorporating two end sections which are interconnected by stationary shafts, said shafts being parallel to said first and second rotating spindles and the centerlines of said shafts being included in a first plane which is at least approximately perpendicular to a second plane including the centerlines of said spindles and the intersection line between said first and second planes at least approximately coinciding with the rotation axis of said roll-holding device, .Iaddend.said two unwinding stations positioned on said roll-holding device, and means to transfer the rotational movement of the associated roll-support spindle to said braking mechanism, said means comprising two free-wheel members, one for each roll support spindle, said members arranged to connect to said braking mechanism that one of said two roll support spindles that at the moment has the highest rotational speed.Iadd., first cog wheels, one on each roll-support spindle at one end thereof, said cog wheels comprised in said means means to transfer the rotational movements of said roll support spindles to said braking mechanism, and second cog wheels rotatably mounted on support arms, said arms forming part of said roll-holding device, said second cog wheels arranged to mesh with said first cog wheels, and all cog wheels being mounted in a first of said end sections of said roll-holding device.Iaddend.. .[. 
     
     
       2.  An improved roller stand according to claim 1, comprising first cog wheels, one on each roll-support spindle at one end thereof, said cog wheel comprised in said means to transfer the rotational movements of said roll support spindles to said braking mechanism, and second cog wheels rotatably mounted on support arms, said arms forming part of said roll-holding device, said second cog wheels arranged to mesh with said first cog wheels..]. 
     
     
       3. An improved roller stand according to claim 1, wherein said roll-holding device is arranged to be turned step-by-step in said frame.Iadd., and wherein the turning movement is transmitted to that second end section of said roll-holding device which does not include said cog wheels.Iaddend.. 
     
     
       4. An improved roller stand according to claim 3, wherein said roll-holding device is arranged for axial adjustment laterally in said frame.Iadd., the lateral movement corresponding to said lateral adjustment being transmitted to said first end section of said roll-holding device, which includes said cog wheels.Iaddend.. 
     
     
       5. An improved roller stand according to claim 1, comprising a momentarily driven roller, said roller arranged to be moved into abutment against the periphery of said second roll the web of which is to be joined to the web of said first roll, said roller arranged to bring the peripheral speed of said second roll to approximately the same level as the peripheral speed of said first roll. 
     
     
       6. An improved roller stand according to claim 1, wherein said means arranged to cut said first unwinding web is connected to a supplementary braking mechanism, said mechanism arranged to apply a braking force on said roll of the unwinding web immediately following the completion of the cutting operation. .Iadd. 7. An improved roller stand comprising a frame, two unwinding stations, a first roll of a web of material, a first rotating spindle supporting said first roll, a second roll of a web of material, a second rotating spindle supporting said second roll, means for joining the web of material being unwound from said first roll to the leading end of the web of material of said second roll, means arranged to transversely cut said first web of material, and a braking mechanism supported by the frame of the roller stand to exert a braking force on said roll support spindles, the improvement comprising a roll-holding device, incorporating two end sections which are interconnected by stationary shafts, said shafts being parallel to said first and second rotating spindles and the centerlines of said shafts being included in a first plane which is at least approximately perpendicular to a second plane including the centerlines of said spindles and the intersection line between said first and second planes at least approximately coinciding with the rotation axis of said roll-holding device, said two unwinding stations positioned on said roll-holding device, and means to transfer the rotational movement of the associated roll-support spindle to said braking mechanism, said means comprising two free-wheel members, one for each roll support spindle, said members arranged to connect to said braking mechanism that one of said two roll support spindles that at the moment has the highest rotational speed, the distance between said stationary shafts being approximately equal to the distance between said rotating spindles. .Iaddend. .Iadd. 8. An improved roller stand comprising a frame, two unwinding stations, a first roll of a web of material, a first rotating spindle supporting said first roll, a second roll of a web of material, a second rotating spindle supporting said second roll, means for joining the web of material being unwound from said first roll to the leading end of the web of material of said second roll, means arranged to transversely cut said first web of material, and a braking mechanism supported by the frame of the roller stand to exert a braking force on said roll support spindles, the improvement comprising a roll-holding device, said two unwinding stations positioned on said roll-holding device, and means to transfer the rotational movement of the associated roll-support spindle to said braking mechanism, said means comprising two free-wheel members, one for each roll support spindle, said members arranged to connect to said braking mechanism that one of said roll support spindles that at the moment has the highest rotational speed, a housing located at an axial end of said roll-holding device, said means for transferring the rotational movement of the associated roll-support spindle to said braking mechanism including a plurality of intermeshing cog wheels extending from each spindle to a common cog wheel, said common cog wheel being operatively connected to said braking mechanism, said cog wheels located in said housing. .Iaddend.