FR2471232A1 - DEVICE FOR DELIVERING SHEETS TO CUTTING AND / OR STAMPING MACHINES AND FOR REMOVING THEM FROM THESE MACHINES - Google Patents

Abstract

DEVICE FOR DELIVERING SHEETS TO A CUTTING OR STAMPING MACHINE AND FOR REMOVING THEM. IN A FRAME 7 ARE MOUNTED MAGNETIC SYSTEMS 8 ADAPTED TO MAINTAINING THE TOLES 1; IN THE INTERVALS ARE MOUNTED, ALL ROTATING AROUND A TRANSVERSAL AXIS WITH RESPECT TO THE DIRECTION OF TRANSPORT, ROLLERS 9 SLIGHTLY EXCEEDING THE ADHESION SURFACE OF THE MAGNETIC SYSTEMS 8, AND THE DISCHARGE CONVEYOR BELT 10 IS PROVIDED TO A CERTAIN DISTANCE UNDER THE RETAINING DEVICE 6. USE IN PARTICULAR WITH CUTTING AND STAMPING MACHINES OPERATING AT HIGH SPEED.

Description

The present invention relates to a device for bringing sheets to

  machines for cutting and / or punching and for taking out and bringing back the sheets of these machines, constituted by conveyor belts, arranged in front of and behind the cutting and / or stamping tool, suitable for conveying

  carry these sheets horizontally and by means of a

  magnetic hold consisting of electromagnetic systems or electromagnetically controlled permanent magnet systems

  disposed in the area of the cutting and / or stamping tool.

  Generally speaking, instead of carrying

  sheets made of magnetizable material using hooks and

  use electromagnets or permanent magnets to bring them suspended at the receiving or processing station. The magnetic systems are arranged above the conveyor belt and, under the action of the magnetic forces passing through the sheet, strongly adhere the sheet to the conveyor belt (see for example the DE-AS

23 46 042).

  The problems facing the invention are the following:

  solvents. The sheets to be cut are unrolled from the spool and, as a rule, are driven through the shears by feed rollers. During cutting, the sheet must remain stationary in the tool, ie the device

  progress is stopped. After the cut, it is necessary that

  the cuts are evacuated at a speed at least equal to the speed of advancement of the following sheets, otherwise there would be recovery between the sheets. The velocity diagram of such a roller feed system has the shape of a sinusoidal curve or follows a trapezoidal pattern with an acceleration segment, a constant velocity segment and a deceleration segment. It is necessary that the speed of the belt conveyor receiving the sheets suspended behind the shear corresponds exactly to this speed chart. However, with the speeds as high as those currently being practiced, the acceleration and deceleration values are so high that a conveyor belt type current can not suffice. The forces due to the masses, the elasticity of

  bands, etc. are so large that it is impossible to synchronize

  in practice, the operation of the roller advancement device and subsequent conveyor belt. This is the reason why so far we use so-called lifting linkages on which the

  sheet metal advances only by friction. These linkage rods

  placed between the evacuation conveyors must be mechanically foldable upwards and downwards

  which is a source of friction and causes deterioration

  sheet metal, while giving rise to a significant noise. For the reasons above, the conveyors

  known, whether band or bar can not satisfy

  to the demands imposed by such rapid and

  careful as possible, bringing the metal sheets to the

  chines to cut and stamp and bring them back.

  The object of the invention is to propose a device

  to transport the sheets very carefully and at a high speed to bring them to cutting machines and / or

stamping machines.

  This result is obtained with a device of the type described at the beginning by the fact that, in a frame or similar device, it is intended to transport in suspended position the sheets

  and maintain them during the cutting and / or stamping operation.

  of magnetic systems, between which are arranged

  rollers slightly protruding beyond the adherence

  this magnetic systems and freely rotating around an axis directed transversely to the direction of transport

  sheet metal, and thanks to the fact that the evacuation conveyor belt

  is placed under the magnetic retainer,

  at a certain distance from it.

  The device according to the invention operates in the manner

next.

  By means of belt conveyors of the current type,

  the cutting and / or stamping are brought into the lying position at the cutting and / or punching machine and, behind the cutting tool and / or stain, are taken by the magnetic retaining device according to the invention . The sheet slides without risk of longitudinal damage on the idler rollers and is pulled by the magnets which are turned on against the rollers. When the sheet has reached its correct position in the machine, the conveyor belt of

? 471,232

  brought is stopped and the cutting operation and / or stamping is performed. Once the cutting and / or stamping operation is completed, the adhesion force of the magnets is cut off, so that the cut and stamped sheet falls from the magnetic retainer onto the conveyor conveyor belt.

  placed below a certain distance. This band

  evacuation voyeur can be driven permanently

  at a constant speed and so there is no need to adapt -

  speed at the working rate of the cutting machine and / or

stamping.

  After the cut and / or stamped sheet fell on

  the evacuation conveyor belt, the sheet to be treated next-

  can be introduced into the machine without being hindered by the sheet that has just been treated. Since the rollers in the magnetic retainer are not driven, the supply conveyor belt can be driven at a variable speed. It is therefore not necessary to adapt the speed diagram of the magnetic retainer to that of the supply conveyor belt. The sheets can therefore be fed to the machine with acceleration and

maximum speed.

  The control of the supply and evacuation operations as well

  cutting and / or stamping operations can be carried out

  killed in the best possible conditions by a

  electronic tif in order to obtain maximum

sheets passing through the machine.

  The features and advantages of the invention

  from the following description.

  for example, with reference to the single figure of the accompanying drawing

  representing in elevation the device according to the invention.

  The sheet 1 resting on the supply conveyor belt 3 arrives in the conveying direction 2 to the cutting and / or stamping machine 4 and, behind the cutting and / or stamping tool, is taken by the machine. magnetic retaining device 6. The magnetic retaining device 6 consists of excitable magnetic systems 8 mounted in a frame 7 or a similar device and by idling rollers 9 over which the sheet 1 passes in suspended position,

  attracted by magnetic systems 8 excited.

  When the sheet 1 has reached its predetermined position

  in the cutting and / or stamping machine 4, the band

  supply feeder 3 is stopped-and the cutting operation and / or

  stamping is done. When this operation is

  In this case, the adhesive force of the magnetic systems 8 in the magnetic retainer 6 is cut off so that the cut sheet 1 is no longer held and falls on the conveyor belt 10 disposed below the device.

  magnetic retainer 6 and can be evacuated.

  After the cut and / or stamped sheet metal 1 has fallen from the magnetic retainer 6, the supply conveyor belt 3 can be put back into operation and the next sheet 1 can be fed into the cutting machine and / or stamp 4 without being hindered by the previously treated sheet metal which has been

evacuated.

  It is not necessary to describe in detail the elec-

  tromagnets or control permanent magnet systems

  electrical interlocking devices used here because we find

  many different types.

  For the rollers 9, plastic material will preferably be used, which makes it possible to avoid perfectly

  sure any deterioration of the sheets.

247 1232

Claims (1)

RESELL ICAT ION   Device for supplying and removing sheet metal to cutting and / or stamping machines, consisting of conveyor belts, on which the sheets are conveyed lying down, arranged in front of and behind the cutting and / or stamping machine , and a magnetic retainer consisting of electromagnet systems or   by permanent magnets electromagnetic-engageable   placed in the area of the cutting tool and / or   Stamping, characterized in that, in a frame or element-ana-   magnetic systems are provided between which rollers slightly protruding from the adherence surface of the magnetic systems are mounted idler about an axis directed transversely to the conveying direction of the plates, and that the conveyor belt of evacuation is   disposed under the magnetic retainer at a some distance from it.