MXPA97007163A - Apparatus for feeding lam material - Google Patents

Abstract

An apparatus for feeding a sheet material comprising a feed table (10) having a gate (11) and on which the sheets (5) can stack against the gate that allows only the sheet that is underneath to pass through is disclosed. below it, a bed (13) of rollers (14) within the surface of the table that can be rotated to drive the sheet that is lower below the gate to the claw of the recovery rollers (12) and means for allowing the rollers to rotate freely once the sheet below is advancing by the action of said recovery rollers.

Description

PflRfl ñlí RPfíflT ENflR LEMMINfl MATERIAL DESCRIPTIVE MEMORY This invention relates to an apparatus for feeding sheet material, particularly, though by no means exlusively, corrugated board or card as used in the industries of manufacture of boxes and cartons. In general, the stacked sheets are placed on a feeding table against a gate that allows only the sheet up to the bottom to pass under it under the action of an oscillating vacuum suction cup, feed rollers or an expanding mechanism, to be-picked up in the grip of the recovery rollers. These feeding arrangements must be controlled with great precision and even after this, feeding errors are not common. A solution to these problems is proposed in copending British Patent Application No. 932,6089.1, of the inventor herein, but this involves oscillating movement of the entire roller bed, which is not energy efficient and places certain restrictions to the size of the sheet. According to the present invention there is provided an apparatus for feeding sheet material comprising a feeding table having a gate and on which sheets can be stacked against the gate which allows only the one below it to pass below it. , a bed of rollers within the surface of the table that can be rotatably urged to advance the sheet that is down below the gate to the grip of the recovery rolls and means to allow the rolls to rotate freely once that the sheet that is lower is advancing by the action of the recovery rollers. The rollers can be equipped with clutches and can advance the sheet being fed at a lower speed than the recovery rolls. You can apply vacuum from below the rollers to pull down the sheet that is lower against them. The rollers can be separated in such a way that the lowermost sheet can hang to give a substantial area contact between the sheet and the rollers. The invention will be apparent from the following description, with reference to the figures of the appended drawings, which show, by way of example only, a form of sheet feeding apparatus which renders the same. From the drawings: Figure 1 shows a side elevational view of the apparatus; and Figure 2 shows a cross-section through the apparatus in line II-II of Figure 1. Referring now to the drawings, it will be seen that the apparatus comprises a feeding table 10 on which a battery can be placed. S sheets against a gate 11 through 1 below which only the sheet below the stack can pass. Susceptive sheets are advanced below the gate 11 towards the grip of the recovery rollers 12 by a bed 13 of rollers 14 within the surface of the table. The rollers are mounted within a chamber 15 to which vacuum suction is applied to pull down the sheet which is lower against them. The space between the rollers 14 allows the sheet to hang between them to increase the contact area. The rollers advance the sheet which is lower by being rotationally driven as indicated by the arrows X at a speed lower than the speed of the recovery rollers 12. Once the sheet is advanced by means of the rollers 12, the rollers 12 rollers 14 of free rotation, the rollers 14 having stop clutches between their internal peripheries and their driving arrows 16. In this example, the rollers 14 are rotatably interconnected by driving bands 17 and a roller 14 is driven by a band 18 which is driven in turn from a toothed band 19 oscillated by an arm 20 operating in synchrony with the speed of the line (typically the one previously used for a mechanism hit, facilitating the re-adjustment). In the reverse stroke of the arm 20, the rollers 14 are not driven in the reverse direction since they are in their free rotation mode. It will be appreciated that it is not intended to limit the invention to the above example only, with many variations being possible as would be possible for one skilled in the art, without departing from the scope thereof as defined by the appended claims. Thus, for example , the rollers 14 can be driven intermittently or continuously by an electric motor, although this is not preferred since in the case of a continuous impeller there will be some sliding between the rear rollers and the next sheet to be fed until the previous lamp has passed gate 11.

Claims (5)

NOVELTY OF THE INVENTION CLAIMS

1. An apparatus for feeding sheet material comprising a feed table having a gate and onto which sheets can be stacked against the gate allowing only the sheet below it to pass underneath it, a roller bed within the surface of the table that can be rotated to advance the sheet that is lower below the gate to the recovery roller grip and means to allow the rolls to rotate freely once the sheet below is advanced by said recovery rollers. An apparatus according to claim 1, further characterized in that the rollers are equipped with stop clutches and advance the sheet being fed at a lower speed than that of the recovery rolls. An apparatus according to claim 1 or claim 2t further characterized in that the vacuum suction is applied from below the rollers to pull the sheet that is lower downwards against them. 4. An apparatus according to any of claims 1 to 3, further characterized in that the rollers are separated in such a way that the sheet which is lower can hang to give a substantial area contact between the sheet and the rollers. 5. An apparatus in accordance with any of the foregoing claims, further characterized in that the rollers are rotatably interconnected by driving belts and one is driven by a driving belt oscillated by an that operates in synchrony with the speed of the belt. 1 ile. 5. An apparatus according to claim 5, further characterized in that said driving belt is serrated. 7. An apparatus according to any of claims 1 to 4 further characterized in that the rollers are driven by an electric motor. 8. An apparatus according to claim 7 further characterized in that the rollers are driven in a manner in rrn11en e. 9. An apparatus in accordance with claim 7 characterized further because the wheels are driven contiguously.