GB2030117A - Apparatus for presenting articles to an upwardly-facing surface - Google Patents

Abstract

The invention relates to apparatus for presenting articles to an upwardly-facing surface, such as presenting printed sheet material from a press to a dryer or onto a stack. The apparatus includes at least one support surface formed to receive an article (P), said formed surface being of flexible material (34), and means (40) progressively to retract said surface into an unformed condition by rolling it from beneath, said means comprising a device arranged to pull said flexible material in a direction having at least in part a downward component of movement. <IMAGE>

Description

SPECIFICATION Apparatus for presenting articles to an upwardly-facing surface The present invention relates to apparatus for presenting articles to an upwardly-facing surface. For example, it may apply to the feeding of articles to a stack or column thereof or to a moving storage surface on which the articles may be laid in a side-by-side disposition.

In a particular example of use of the invention, the apparatus may be used to transfer to a dryer articles such as printed sheet material from a conveyor bringing the material from a print machine to a position immediately adjacent the dryer. It is an object of the invention to provide apparatus for presenting articles which involves the minimum handling of the articles and risk of damage thereto.

The invention therefore provides apparatus for presenting articles to an upwardly-facing surface, comprising at least one support surface formed to receive an article, said formed surface being of flexible material, and means progressively to retract said surface into an unformed condition by rolling it from beneath, said means comprising a device arranged to pull said flexible material in a direction having at least in part a downward component of movement. Conveniently, the material is in the form of a continuous.web. Advantageously, the material is gripped firmly at one region thereof during the pulling movement.

In one example, a receptacle may be provided to collect the material as it is retracted and store it in a looped or folded condition between operations of the machine. Alternatively, the loops or folds of material may be held on vertically adjustable rollers.

It may be found convenient to pass the material over a rod or slat which traverses the desired location of the surface in an outward, extending movement or a return, retracting movement in the formation and retraction of the support surface. If desired the outward movement may be continuous to carry and deposit one article onto a receiving surface or stepwise to carry and deposit a number of articles onto the receiving surface. The article(s) to be placed on the support surface may thus be fed onto the support surface as it is formed and travel across the apparatus as the support surface is extended.

There will now be described two apparatuses in accordance with the invention. It will be understood that the description, which is intended to be read with reference to the accompanying drawings, is given by way of example only and not be way of limitation.

In the drawings: Figure 1 shows, in side elevation, an outline of the first apparatus and its housing in relation to a dryer for printed sheet material; Figure 2 shows a diagrammatic side eleva tion view of the apparatus with its housing removed for the sake of clarity; Figure 3 is a plan view of the apparatus without its housing; Figure 4 is a view, in side elevation, of an outline of a second apparatus and its housing; Figure 5 shows a diagrammatic side eleva tion view of the apparatus without its housing; and Figure 6 is a diagrammatic perspective view of a portion of the second apparatus.

Fig. 1 shows a cantilevered housing ar rangement 2 comprising an upright frame 4 standing at one side of a drying apparatus for printed sheet material which apparatus may be of the type described in the complete specification of British Patent Application No.

24987/77 (25/1/80). Whatever type of ap paratus is installed in the position shown at 6 in broken lines, it will be of the kind in which a flat upwardly facing surface is provided onto which articles are to be placed. Such articles are in the present example separate sheets of printed material, P, which are carried one at a time by a conveyor 7 from the print machine (not shown).

The housing arrangement also includes an overhanging portion 8 directly above the ap paratus 6. The housing portion 8 includes two guide rails 10 extending parallel from the upright frame 4 and arranged to receive end portions of a slat 1 2 extending between the guide rails. The profile of left-hand edge 14 of the slat as viewed in Fig. 2 is rounded.

A pair of wires 1 6 are provided each of which is connected at an intermediate region thereof with one end portion of the slat 1 2.

Each wire 1 6 is connected at its two ends to pulley wheels 1 8 and 20 respectively hav ing intermeshing gear teeth arranged so that the two pulley wheels rotate in mutually oppo site directions, driven through a V-pulley 22 from a reversing motor 24. The wire 1 6 passes from the pulley wheel 1 8 over a freely rotatable pulley 26 and through a bore in the end portion of the slat 1 2 into which the wire is secured. The wire 1 6 leaves the slat 1 2 at the rounded edge 1 4 and then passes around a pulley 28 to return via a small roller 30 to a freely rotatable pulley 32 and then to the pulley wheel 20.

Thus rotation of the pulley wheel 1 8 in a clockwise direction causes the wire similarly to rotate the pulley 26 and draw the slat in a left-to-right direction as viewed in Figs. 1 and 2. The wire also moves around pulley 28 and 32 in a paying-out action controlled by the anti-clockwise rotation of the pulley wheel 20.

The other wire is similar in mounting and operation.

Reversal of the motor 24 and thus of the direction of rotation of the pulley wheels causes the movement of the slat also to be reversed so that it travels from right to left, the wire this time paying out from the pulley wheel 18.

A continuous web of flexible mesh material 34 is arranged in the apparatus so as to pass in a taut condition around the edge 14 of the slat 1 2. The path of the material is over two rollers 36 and 38, mounted co-axially be tween the pulleys 26 and the pulleys 32 respectively. It is to be stressed that the diameters of the pulleys 26 and 32 of the rollers 36 and 38 are all identical, but for the sake of clarity, Fig. 2 has been drawn with the rollers having a larger relative diameter than is actually the case. The path of the web material passes downwardly over the slat edge 14 and to the right as shown in the Figure, then over the roller 36 and through a system of gripper rollers 40 operated by a motor 42.

The material is received in a container 44 and the path continues upwardly to the roller 38 over which it passes to the slat 1 2.

The operation of the apparatus is as fol lows: Formation of the Support Surface The parts of the apparatus are in the position shown in Fig. 2, with the slat 1 2 retracted and the excess web material 34 folded in the receptacle 44. The motor 24 then operates to cause the pulley wheel 20 to rotate clock-wise to pull the wire 1 6 on each end of the slat 1 2. This causes the slat to move to the left as viewed in Fig. 2, pulling with it the web 34 which advances over both rollers 36 and 38, so that there is no relative movement between the web 34 and the slat edge 1 4. The advance of the slat along the guides 10 may be continuous so that as the leading edge of a printed sheet P is received on the support surface the slat is just commencing its travel.As it continues the sheet P is carried with it, the rate of progress of the slat being the same as the rate of travel of the conveyor 7. Alternatively the progress of the slat may be stepwise which is convenient if a number of relatively small sheets of printed material are to be placed on the support surface. Each sheet may be fed from the conveyor 7 at each step of the advancing movement. At the end of the advancing movement, only one fold of web material remains in the receptacle 44.

Retraction of the Support Surface As soon as the entire sheet of printed material, or the last sheet as the case may be, is received on the support surface formed by the web 34 and the slat has reached its furthest point of advance, the motor 42 is activated to operate the rollers of the webgripping arrangement 40 to pull the lower run of the web 34 to the right. At the same time the motor 24 is reversed to cause the pulley wheel 1 8 to rotate in a clockwise direction, thus pulling the wire 1 6 so that it pulls the slat back towards its starting position.

It will be observed that the upper run of the support surface formed by the web 34 re mains stationary while its area is reduced by rolling the lower run from under the upper one. This is ensured by arranging that the roller 38 remains stationary although its associated pulleys 32 are rotating in an anticlockwise direction to pay out the wire 1 6.

Thus the sheet of printed material is laid directly onto the top level of the dryer appa ratus 6, or, if several small sheets are positioned, these are undisturbed and laid side by side on the dryer.

Alternatively, instead of placing the sheets on a dryer they may be placed one on top of the other in a stack. it will then be found convenient to provide immediately below the support surface a tray arrangement (not shown) which is successively lowered as the height of the stack increases to maintain the topmost sheets of the stack at the appropriate level.

Fig. 4 shows a diagrammatic view of the second apparatus in which the advance and retraction of the support surface is carried out in a similar manner to that described above, an important difference being that instead of retracting the formed surface by means of gripping means acting to pull the material in a generally downward direction so that the material is received in folds in a receptacle, the folds of the temporarily excess material are taken up on a series of vertically adjustable rollers as described below.

The Figure shows a cantilevered housing arrangement 52 comprising an upright frame 54 standing at one side of drying apparatus 56 for printed sheet material.

An overhanging portion 58 includes two guide rails (not shown) in which are received end portions of a slat 62 in a similar manner to that of slat 1 2 in the previous example.

The slat 62 in the present example is driven by connection of end portions thereof to each of two chains (not shown) driven from a pair of toothed wheels 64, one on each side of the apparatus (Fig. 6). A continuous web of flexible mesh material 66 is arranged in the apparatus so as to pass in a taut condition around an edge 68 of the slat 62. The material extends rearwardly from the upper surface of the slat 62 over a roller 70 and from the lower surface of the slat 62 over a roller 72. The remainder of the length of web is folded into a zig-zag formation over a roller 74 secured to the frame of the apparatus, and two further rollers 76, the position of which is adjustable vertically in the apparatus. The rollers 76 are weighted rollers and are free to fall under the influence of gravity whenever the state of tension in the material web permits, by a distance governed by the available length of the web. An end tie 78 links the two rollers 76 to maintain their proximity to one another at all times. A buffer means 80 forms an end stop to limit the extent of downward movement.

The position of the slat 62 in Fig. 4 in full lines illustrates a point at the beginning of the travel across the apparatus in a right-to-left direction as viewed in the Figures. A motor 80 is provided together with a clutch-brake device 82 to drive the wheel 64 through belts 84. The clutch is engaged and the chain drive brings the slat forwardly (leftwards) towards the position shown in broken lines at 62'. As it travels it pulls the material 66 over the rollers 70, 72 and the weighted rollers 76 commence to rise to a position shown in broken line at 76'.

Passage of the material over the roller 70 causes two small rollers 86 to rotate freely, but these rollers are of the one-way type and when the clutch is disengaged and a further motor 88 is operated to reverse the direction of the slat 62 (to the right), the rollers 86 being unable to rotate in the reverse direction, jam against the rollers 70 trapping the material 66 therebetween. Therefore, when the slat travels to the right the material is withdrawn over rollers 72 and 74 by the weight of the rollers 76 which return to their full line position as in Fig. 4.

As described, the forward movement of the web of material 66 is continuous, but it may be desirable under some operating circumstances to advance the support surface formed by the material in a stepwise manner.

In this way a number of articles may be fed into the support surface, all of which will then be placed onto a lower take-off surface during retraction of the support surface. A convenient control means for a stepwise operation of the drive to the wheel 64 may be provided by a microswitch assembly (not shown) mounted on an externally threaded extension of a shaft 90 axially rotating with the clutch/brake device 82. Rotation of the shaft extension will cause an internally threaded member to move axially to operate a series of microswitches in a desired pattern to obtain a number of interruptions in the advance of the slat 62.

Where lightweight articles are to be carried on the support surface it may be found necessary, for example with thin-gauge printed paper, to provide a pressure differential between the region immediately above the article on the web and that below it. This may be achieved in one of two ways. Air jets (not shown) are mounted above the articles on the material and these jets hold the articles in place. Alternatively, suction may be applied to the region immediately below the web in the region of the article lying thereupon.

Various modifications may be made within the scope of the invention as defined by the following claims.

Claims (11)

1. Apparatus for presenting articles to an upwardly-facing surface, comprising at least one support surface formed to receive an article, said formed surface being of flexible material, and means progressively to retract said surface into an unformed condition by rolling it from beneath, said means comprising a device arranged to pull said flexible material in a direction having at least in part a downward component of movement.

2. Apparatus as claimed in claim 1, where the material is in the form of continuous web.

3. Apparatus as claimed in claim 2, wherein the flexible material is gripped firmly at one region thereof during the pulling movement.

4. Apparatus as claimed in claim 3, wherein the means for pulling the material in a direction having at least in part a downward component of movement include gripping means to grip the material firmly.

5. Apparatus as claimed in claim 4 wherein a receptacle is provided to collect the material as it is retracted by pulling and to store it in a looped or folded condition.

6. Apparatus as claimed in claim 3 wherein there are provided vertically movable rollers, the weight of which rollers permits material to be retracted by rolling it in the desired direction from beneath the support surface into a looped condition, said material being gripped firmly in the region of the support surface to prevent unwanted rolling movement in the opposite direction.

7. Apparatus as claimed in any one of the preceding claims, wherein a rod or slat is provided over which the material is passed, means being provided to cause said rod or slat to traverse the desired location of the surface in an outward, extending movement or a return, retracting movement, in the formation or retraction respectively of the support surface.

8. Apparatus as claimed in claim 7, wherein the outward extending movement of the rod or slat is made in a stepwise manner.

9. Apparatus as claimed in claim 7, wherein the outward, extending movement of the rod or slat is made in a continuous manner.

1 0. Apparatus as claimed in any one of claims 2 to 9, wherein means are provided for a pressure differential between the region immediately above an article on the support surface and the region below, the pressure in the first mentioned region being higher than that in the second mentioned region.

11. Apparatus for presenting articles to an upwardly-facing surface, constructed arranged and adapted to operate substantially as hereinbefore described with reference to and as shown in Figs. 1 to 3 of the accompanying drawings.

1 2. Apparatus for presenting articles to an upwardly-facing surface, constructed arranged and adapted to operate substantially as here inbefore described with reference to and as shown in Figs. 4 to 6 of the accompanying drawings.