This invention relates to an apparatus for forming sheet material articles, and more particularly in one aspect an apparatus for covering articles with sheet material and, in another aspect, an apparatus for use in forming blanks, for example for cartons or boxes or boards for the covers of books. Show cards are often formed by placing a single board or card or similar flat substrate onto a pre-glued sheet of covering material such as buckram, leather or fabric. The covering material is larger than the substrate, so that the edges of the covering material can be folded over the edges of the substrate. A lining material may then be adhered to the uncovered side of the substrate. Menu cards, book and pattern book covers, game boards and other sheet material articles can be formed in a similar manner by placing two or more substrates onto the pre-glued sheet of covering material.

Hitherto, book covers etc. have been formed on a small scale by manually placing boards onto a pre-glued sheet of covering material by hand. The cover is then inserted into a machine which folds over the edges of the covering material. EP 0 461 083 discloses one such machine which automatically folds over the four edges of the covering material, however the machine is complicated because it uses two perpendicular conveyors which successively transport the cover to four folding arrangements which independently fold respective edges of the cover.

We have now devised an apparatus for making sheet material articles which is more automated, but which is less complicated than conventional apparatus.

In accordance with this invention, as seen from a first aspect, there is provided an apparatus for covering articles with sheet materials, the apparatus comprising a conveyor arranged to transport a sheet of covering material coated with an adhesive and to halt when the sheet of covering material reaches a position where it is in face-to-face registration

with a flat substrate to be covered, the apparatus further comprising means arranged then to bring the substrate into face-to-face contact with the sheet of covering material so as to adhere the latter to the substrate. In order to cover the substrate accurately, preferably the flat substrate is positioned in a known position and orientation relative to the sides and opposite ends of the conveyor. The sheet of covering material is placed on the conveyor in the desired lateral position relative to the sides of the conveyor, and hence relative to the width of the substrate. The conveyor is then driven to move the sheet of covering material into its said position where it is in registration with the substrate. The desired longitudinal alignment of the two materials is achieved by stopping the conveyor when the sheet of covering material reaches a point at which the substrate can be brought directly into face-to- face contact with the latter e.g. by moving it in a linear direction, preferably normal to the plane of the conveyor.

As the sheet of covering material is fed onto the conveyor, it may slip and thus become slewed on the conveyor. Preferably alignment means are provided for rotating the flat substrate about an axis which extends perpendicular to its plane, so as to compensate for any slew of the sheet of covering material prior to bringing the substrate into face-to- face contact with the sheet of covering material.

The distance through which the conveyor is driven is determined from data regarding the lengths of the substrate and sheet of covering material and their desired alignment. For example, in some cases the conveyor may be arranged to halt when the sheet of covering material is at a longitudinal position which is central in relation to the substrate, but in other cases it may be arranged to stop when the sheet of covering material is at a predetermined longitudinal position offset relative to the longitudinal centre of the substrate. Preferably means are provided for detecting an edge of the sheet of covering material on the conveyor, in order to determine the position of the sheet of covering material, and so that the conveyor can be driven to transport the covering material to the position where it is in face-to-face

registration with the substrate: preferably this detecting means also detects the opposite edge of the sheet of covering material, in order to determine the length of the covering material. Alternatively the length of the sheet of covering material may be pre-programmed into the apparatus, so that the position of its opposite edge can be calculated from the position of its known edge.

Preferably a photodetector is arranged to detect said edge(s) of the sheet of covering material, the conveyor being arranged to transport the covering material past the photodetector prior to positioning it in face-to-face registration with the substrate.

Preferably a pair of photodetectors are arranged on a line which extends perpendicular to the direction of movement of the conveyor, the photodetectors being arranged on either side of a line which extends longitudinally along the conveyor. The signals from the photodetectors are used to determine whether the sheet of covering material is slewed on the conveyor. Thus, if the signals from the two photodetectors are out of phase, then it will be apparent that the sheet of covering material is slewed.

Preferably the apparatus is arranged to cover a group of substrates with one or more sheets of covering material.

In one embodiment, the conveyor is arranged to transport the substrate(s) and the sheet of covering material in succession along the conveyor, means being provided for then displacing the substrate(s) from the conveyor so that the latter can subsequently position the sheet of covering material in face-to-face registration with the substrate(s) , the displacing means being arranged then to bring the substrate(s) into face-to-face contact with the sheet of covering material.

The conveyor is preferably arranged to advance a predetermined distance between successive substrates in a group as they are being fed onto the conveyor, so that a predetermined gap is formed between adjacent members of the group.

In another embodiment, the apparatus is arranged so that the sheet of covering material is transported to a position where it is in face-to-face registration with a hopper

containing the substrate(s) , means being provided for then displacing the substrate(s) in the hopper to bring the substrate(s) into face-to-face contact with the sheet of covering material. Preferably the apparatus is arranged to fold the covering material over the edges of the substrate(s) , preferably by means of a rotating roller brush mounted with its axis parallel to the plane of the conveyor and extending perpendicular to the direction of movement of the conveyor. Preferably a pair of such roller brushes are provided, so that opposite end edges of the covering material are folded over by the respective brushes when the conveyor is successively advanced and reversed.

Preferably a pair of rotating brush wheels are arranged to fold over opposite side edges of the covering material. Preferably the spacing between the brush wheels can be adjusted to suit different widths of substrate(s) . Preferably these brush wheels can be removed and replaced by similar brushes having different characteristics, e.g. stiffness of bristles. Conventional conveyors comprise a wide continuous belt which passes around end rollers. If the end rollers are not exactly parallel to each other, then there is a danger that sideways movement of the belt will occur as it is advanced. Another disadvantage of wide conveyors is that they comprise strips joined end-to-end to form loops. Such belts frequently break along the join line.

Thus, in an apparatus in accordance with this invention, preferably the conveyor comprises a plurality of belts mounted side-by-side. These belts may be guided, so that no tracking problems occur. Furthermore, narrow belts can be formed as continuous belts, and thus do not suffer from the drawback of breakage.

Preferably the means arranged to bring the substrate into face-to-face contact with the covering material comprises an assembly which can be raised away from or lowered onto the conveyor. Preferably the substrate is held on the assembly by means of suction.

Preferably the apparatus comprises means for applying adhesive to the covering material. The glue may be applied

e.g. by a roller as the covering material is fed onto the conveyor.

Preferably the apparatus is controlled by a microprocessor, such as a personal computer (PC) . Cartons and boxes are formed by cutting flaps and tabs in blanks formed from cardboard or other sheet material. Fold lines are formed on the blank so that it can be folded into shape. Hitherto, cartons and boxes have been formed in this way using an apparatus having blades which descend to cut out the shape of the blank. These apparatus are set manually and are therefore time consuming to set up.

In accordance with this invention as seen from a second aspect, there is provided an apparatus for use in forming blanks for a carton or box, comprising a conveyor which advances sheet materials on the conveyor towards a tool mounted for movement transverse to the direction of movement of the conveyor, and means for controlling the movement of the tool and/or conveyor in order to cut and/or score the sheet material. Thus, in use the movement of the tool and/or conveyor can be controlled to cut slots and remove panels from sheet materials, in order to form blanks which can be folded into boxes or cartons.

Preferably the movement of the tool and/or conveyor is controlled by a microprocessor, for example a personal computer (PC) . The user may enter the dimensions of the box or carton into the microprocessor, which is arranged to calculate the correct movement of the tool and/or conveyor to give the required arrangement of slots and/or panel cut-outs to form the box.

The tool is able to cut parallel to the side edges of the sheet material by advancing the conveyor whilst keeping the tool stationary. Perpendicular cuts may be formed by stopping the conveyor and moving the tool transversely. Alternatively, diagonal cuts may be formed by simultaneously advancing the conveyor and moving the tool.

Preferably a second tool mounted for transverse movement perpendicular to the direction of movement of the conveyor forms score lines in the sheet material.

Preferably the cutting tool is mounted between a pair of conveyors disposed end-to-end, so that the head of the cutting tool is able to cut through the sheet material without coming into contact with the conveyors. Although the apparatus has been described for use in forming blanks for cartons or boxes, it may also be used for cutting boards, to the required rectangular size, for the covers of books.

Embodiments of this invention will now be described by way of examples only, and with reference to the accompanying drawings, in which:

FIGURE 1 is a perspective view of a covering apparatus in accordance with this invention;

FIGURE 2 is a perspective view of a portion of the covering apparatus of Figure 1;

FIGURE 3 is a sectional view through the conveyor of the covering apparatus of Figure 1;

FIGURE 4 is a perspective view of a partially formed book cover which has been formed using the covering apparatus of Figure 1;

FIGURE 5 is a perspective view of an apparatus in accordance with this invention for use in forming blanks for cartons or boxes, with some parts of the apparatus omitted for clarity; FIGURE 6 is a sectional view along the lines VI - VI of Figure 5; and

FIGURE 7 is a sectional view along the line VII-VII of Figure 5.

Referring to Figures 1 to 3 of the drawings, there is shown a covering apparatus comprising a horizontal conveyor 10 mounted on a pair of rollers 11,12. The conveyor 10 comprises a plurality of side-by-side toothed belts 13 each journalled in respective guide channels 57. The roller 12 comprises toothed drive wheels driven by a servo motor (not shown) . A vacuum chamber 15 is disposed between the rollers 11,12 and between the upper and lower runs of the conveyor 10. The vacuum chamber 15 is divided into a plurality of pairs of longitudinal compartments 50 which co-extend with the belts 13, each such pair of compartments consisting of an upper

compartment 50a and a lower compartment 50b. Each belt 13 is journalled in respective guide channels 57 formed around two such compartments 50. The compartments 50a, 50b for each belt 13 are formed by two E-section aluminium extrusions 49 bolted back-to-back, with a flat plate 51 disposed in between. The upper and lower edges of the plate 51 project slightly above the upper and lower surfaces of the extrusions 49 respectively, and thus form longitudinally extending belt guide ridges. A slot 13c is formed around the inner periphery of each belt intermediate its opposite side edges for receiving the ridge. The compartments 50a, 50b of adjacent belts are separated by dividing walls 63 comprising three plates 52,53,52 mounted face-to-face. The outer plates 52 are the same size as the plate 51, and thus form further longitudinally extending belt guide ridges. The opposite side edges of each belt 13 are stepped, so that each belt 13 seats between opposed plates 52 of adjacent dividing walls. The middle plate 53 of each dividing wall 63 projects beyond the plates 51,52, and has its edges flush with the upper and lower surfaces of the conveyor. Apertures 54 are formed at intervals along the upper and lower wall of each compartment 50a, 50b respectively. These apertures 54 communicate suction from the compartments 50a or 50b to apertures 16 in the belts 13. The apertures 16 only extend part-way around the belts 13, thus when the belts are mounted side-by-side on the conveyor they form a matrix of apertures. Alternatively the belts 13 may be perforated along their entire length. Suction is applied either to the upper compartments 50a or to the lower compartments 50b, depending whether the apparatus is being used in semi-automatic mode or fully automatic mode, as will be described.

A gate 17 extends transversely across the conveyor 10 adjacent its front end and is arranged to be raised or lowered: for this purpose the gate 17 may be coupled to a support frame 26 which is raised or lowered. A pair of moveable guides 18 extend towards the front of the conveyor 10 and define a zone 19 on the conveyor onto which the board or boards for the cover are placed during semi-automatic operation of the apparatus.

Before using the apparatus the user has to set the apparatus to the width of board which he is using. This is

achieved by turning a handwheel 20 to turn a pair of interconnected shafts 20a and cause two parallel bars 21,21 of an adjustment mechanism 61 to move apart or together (see Figure 2) ; bars 21,21 carry respective ones of pairs of control fingers e.g. 22 which move members such as the guides 18. Thus, when the handwheel 20 is turned, the guides 18 move apart or together depending on the direction in which the wheel is turned. The user therefore has to turn the handwheel 20 until the spacing between the guides corresponds to the width of the boards being covered. Instead of being turned by a handwheel, the shafts 20a may be motor driven.

A plurality of light-emitting devices 23,24 are mounted on the rear side of the gate 17, and corresponding pairs of photodetectors e.g. 24b are mounted below the conveyor 10. The light-emitting devices are aligned with apertures 58 which extend through the dividing wall 63 between opposite sides of the conveyor. When the user operates the adjustment mechanism 61, a further pair of fingers 25 control which pair of light- emitting devices and photo-detectors 23 or 24 are enabled. A magnetic or optical reference mark is disposed on the conveyor 10, so that the position of the conveyor can be determined.

A horizontal board support frame 26 is disposed above the conveyor 10, intermediate the gate 17 and the opposite end of the conveyor. The frame 26 comprises front and rear transverse bars 27,28 interconnected by a bar 29 which extends lengthwise over the centre of the conveyor 10. Two parallel moveable bars 30,31 are mounted on either side of the central bar 29, and the position of these two bars is also controlled by fingers 32 of the adjustment mechanism 61. A plurality of downwardly-directed vacuum cups (not shown) are mounted on the three bars 29,30,31 which extend lengthwise of the conveyor. The positions of the vacuum cups along their respective bars is set manually depending on the length of the boards being covered. The user also has to select which size of cup is used depending on the size of the boards being covered e.g. small diameter cups are needed for narrow strips of board.

A pair of transverse elongate brush rollers 33,34 are mounted to opposite ends of the frame 26, and two pairs of

moveable pinch wheels 35,36 are also mounted to the frame, outwardly of the rollers 33,34 respectively. The spacing between the pinch rollers 35,36 of each pair is also controlled by two pairs of projecting fingers 37,38 of the mechanism 61. The servo-motor which drives the conveyor 10 is connected thereto by a clutch, and the direction of the servo-motor can be reversed to drive the conveyor in opposite directions. Another clutch connects the motor to a mechanism which raises and lowers the frame 26, rollers 33,34 and pinch wheels 35,36. The operation of the apparatus is controlled by a microprocessor, for example a personal computer (PC) .

Two pairs of moveable brush wheels 39,40 are mounted adjacent the rear end of the conveyor 10 with their axes parallel to the direction of movement of the conveyor. The brush wheels 39,40 are mounted such that their bristles project below the plane of the upper surface of the conveyor 10. A transverse roller 41 is mounted in line with the rear end of the conveyor 10, behind the brush wheels 39,40. Two further transverse rollers 42,43 are biassed into engagement with the upper and lower sides of the roller 41 respectively.

The brush wheels 39,40 are moved by fingers 44 (Figure 2) towards or away from the centre line of the conveyor, when the adjustment mechanism 61 is operated.

The brush rollers 33,34 and brush wheels 39,40 are driven by motors (not shown) . A movable gluing roller assembly 46 is mounted at the front end of the conveyor to apply glue to the covering materials as they are fed onto the conveyor.

Figure 4 of the drawings shows a partially-assembled book cover comprising three rigid boards 67,68,69 adhered to a sheet of covering material such as buckram, the apparatus being used in semi-automatic mode. The centre board 68 forms the spine of the book, whilst the two outer boards 67,69 form the front and rear covers respectively.

At the start of the covering operation, to form the book cover of Figure 4, the number of boards (e.g. three for the book cover shown) is entered on the keyboard of the PC which controls the apparatus. The value for the spacing S between adjacent boards can also be set by the user, or alternatively it can be left at a default value. Once the settings have been

made, vacuum is applied to the upper vacuum-compartments 50a, and the conveyor advances until the matrix of apertures 16 in the belt is disposed at the front of the conveyor on its upper surface. The first board 67 is then manually inserted onto the zone 19 of the conveyor 10. Using the adjustment mechanism 61, the guides 18 are adjusted to centre the board 67 on the conveyor, and to correspondingly set the other above-mentioned parameters dependant on the board width. Then by pressing a start button, the gate 17 is raised and the conveyor 10 advances to carry the first board 67 into the apparatus. The outermost pair of photo-detectors are enabled and are obscured by the board 67 as it advances, so that the emitted light is no longer detected. The output from the photo-detectors therefore changes at the start and end of the board 67. The PC is thus able to determine the length and position of the board on the conveyor.

Once the end of the first board 67 has been detected, the conveyor 10 continues to advance for a distance equal to the required board spacings, before stopping. This process is then repeated until all three boards being covered, i.e. boards, 67,68,69, have been fed into the apparatus. Once the end of the third board 69 has been detected, the conveyor 10 advances to centre the boards 67,68,69 longitudinally with respect to the support frame 26. The motor which drives the conveyor is then disengaged from the conveyor 10 via the respective clutch. The second clutch is then engaged to lower the support frame 26 by about 1cm, so that the vacuum cups carried by the frame 26 lie on top of the boards 67,68,69. The boards are transferred from the conveyor 10 onto the frame 26 by switching the suction from the conveyor to the vacuum cups. The frame 26 then raises to lift the boards 67,68,69 away from the conveyor 10. Next the conveyor 10 advances until the matrix of apertures 16 in the belt is again disposed at the front of the conveyor on its upper surface. Suction is applied again to the upper vacuum compartments 50a under conveyor 10, and a sheet of covering material 70 is then fed onto the upper surface of the conveyor as it advances. The covering material 70 may be fed from a hopper 66 at the front of the conveyor, alternatively it may be fed manually using a feed tray (not

shown) . As the sheet of covering material 70 is fed onto the conveyor, it passes over a gluing roller assembly 46, which applies glue to the upper surface of the sheet of covering material. The sheet of covering material 70 interrupts the beam from the photo-detectors 24, and thus the PC is able to calculate how far to advance the conveyor in order to position the glued sheet of covering material 70 in face-to-face registration with the boards 67,68,69 on the frame 26.

Next, the frame 26 is lowered so that the boards 67,68,69 are placed on the glued sheet of covering material 70.

The suction is then removed from the vacuum cups of the support frame, so that the assembled cover remains on the conveyor 10.

Once the cover has been assembled as described above, the conveyor 10 then advances, so that the leading edge of the covering material 70 is folded over the end edge of the third board 69 (as shown in Figure 4) by the roller brush 33 on the end of the support frame 26, which roller brush is rotating in an opposite sense to the direction of movement of the conveyor. The bristles of the roller brush 33 extend between adjacent belts of the conveyor, and thus lift the edges of the covering material away from the conveyor. The pinch rollers 35 press down the folds at the two corners at that end of the assembled cover. The conveyor is then reversed so that the opposite end edge of the covering material 70 is folded over the first board 67 by the other roller brush 34 on the opposite end of the support frame 26, which roller brush is rotating in an opposite sense to the direction of movement of the conveyor. The pinch rollers 36 press down the folds at the two corners at that end of the assembled cover. Then the roller brushes 33,34 and pinch rollers 35,36 are lifted clear to allow the conveyor 10 to advance the cover towards the brush wheels 39,40, which simultaneously fold over the opposite side edges of the material. Once all four edges of the covering material have been folded over the boards 67,68,69, the finished cover is ejected from the apparatus through the rollers 41,42, which iron out any creases and air bubbles.

For a f lly-automatic mode of operation of the apparatus, substantially a mirror image of the parts used in

the above-described semi-automatic mode are provided on the underside of the conveyor. In order to change from semi¬ automatic to fully-automatic modes of operation, the user has to adjust the covering material feed and the gluing roller assembly 46, so that glued material is fed onto the underside of the conveyor 10 rather than the upperside. A hopper 71 is loaded with the boards to be covered, and the sheets of covering material 70 are fed automatically onto the underside of the conveyor 10 from the hopper 66. The conveyor 10 then positions the sheet of covering material 70 in face-to-face registration with the board or boards in the hopper 71. The hopper 71 then moves upwardly so that the top board or boards are adhered to the sheet of covering material 70. The conveyor then advances as described above in order to fold over the edges of the sheet of covering material 70, using brush rollers 73,74 mounted to the hopper 71. The finished cover is ejected from the machine before the process then repeats itself.

If the covering material is misfed onto the conveyor, or if it slips as it passes over the gluing roller, then it will be slewed on the conveyor, and thus the cover will not be assembled correctly. In order to prevent this, signals from the enabled pair of photodetectors 24 are used to determine whether the leading edge of the sheet of covering material is perpendicular to the direction of movement of the conveyor. Thus, if the signals from the photodetectors 24 are out-of- phase, then it will be apparent that the sheet of covering material is slewed. The signals from the photodetectors 24 are fed to the PC, which is able to calculate the angle of slew. The board support frame 26 and/or the hopper 71 are connected to actuators (not shown) which can rotate the boards about an axis H which extends perpendicular to their planes. The PC outputs control signals to the actuators to rotate the boards through an appropriate angle and in the required direction to correct for slewing of the sheet of covering material. The boards are then brought directly into face-to-face contact with the slewed covering material.

It will be appreciated that the above-described apparatus is compact and ideally suited for low-volume covering operations, whether used in semi-automatic or fully-automatic

mode. It will further be appreciated that alternative embodiments may be arranged for either semi-automatic operation only or fully-automatic operation only.

Referring to Figures 5-7, there is shown an apparatus for use in forming a blank for a carton or box, but which may also be used to cut boards, to the required rectangular size for the covers of books. The apparatus comprises three conveyors 80,81,82 mounted end-to-end. The conveyors and their associated sheet material feed and suction mechanisms may correspond in construction and operation to those described in Figures 1 to 3 of the drawings. Supports 83,84 are mounted transversely between the conveyors 80,81 and 81,82 respectively. Each support 83,84 comprises upper and lower horizontal arms 85,86 which extend, respectively, above and below the conveyors, and a central arm 87 which extends between the planes of the upper and lower runs of the conveyors 80,81,82.

A tool 88 is mounted on the upper arm 85 of the support 83 for movement perpendicular to the direction of movement of the conveyors 80,81. The tool 88 is keyed to a threaded shaft 91 which can be rotated about its axis to move the tool 88. A lower tool 89 is mounted to the central arm of the support 83 and is arranged to move in synchronism with the tool 88. The tools 88,89 are free to rotate about their vertical axes, and each carry a pinch wheel 90 on their lower and upper surfaces respectively. The tool 88 can be moved axially upwardly or downwardly by raising or lowering a bar 97.

In use, the pinch wheels 90 are used to score fold lines on sheet materials held on the upper surface of the conveyors 80,81. To form a score line parallel to the side edges of the sheet material, the conveyors 80,81 are advanced, and the tool 88 is lowered to pinch the material between the two pinch wheels 90. The tools 88,89 each turn about their vertical axis to a position where the pinch wheels 90 are able to rotate about their axes across the upper and lower surfaces of the material, to form a score line. Transverse score lines may be formed by stopping the conveyors 80,81 and moving the tools 88,89 in synchronism along the support. Alternatively diagonal score lines may be formed by advancing the conveyors

and moving the tools 88,89 simultaneously.

Once the score lines have been formed the conveyor 81 advances the sheet material towards the support 84. The support 84 is provided with a similar pair of movable tools 92,93 on its upper arm 85, which can be raised or lowered. The tool 92 comprises a so-called nibbler having a shaft 94 which carries a C-shaped cutting tool 95. The tool 95 engages with a die 96 at the base of the shaft and punches a C-shaped segment out of the sheet material resting on the upper surface of the die 96. Thus, the nibbler 92 may be used to cut the sheet material by reciprocating the cutting tool 95 whilst moving it relative to the material. The nibbler may be rotated, and the direction of the cutting line may be controlled by moving the conveyors 81,82 and/or the nibbler 92. To form slots and cut panels out of the centre of the sheet material, a hole is formed in the material by lowering the tool 93 to cut away a disc. The nibbler may then be inserted through the cut hole.

The conveyors 80,81,82 and tools 88,89,92,93 are controlled by a microprocessor, for example a personal computer (PC) . Thus, the apparatus is able to automatically cut sheet material blanks to the required size, and can also form the necessary score lines and slots if the blank is to form a carton or box. The dimensions of the carton or box can be entered on the keyboard of the microprocessor, which is then able to calculate where to cut and where to form slots and score lines. The sheet material blanks are manually fed onto the conveyor 80 in a similar manner to the covering apparatus. The position of the leading edge of the blanks are determined by a photo-detector (not shown) .

Similar tools for scoring lines and for nibbling and sawing are disposed on the lower arms 86 of the supports. These tools may be used in a fully-automatic version, in which the sheet material is fed from a hopper (not shown) on the underside of the conveyors. To increase the speed of the carton making operation, two or more tools may be provided on each support to simultaneously work on the sheet material.

A printing head such as a dot matrix or ink jet may be mounted for transverse movement over one of the conveyors, in

order to print onto the sheet material.

It is envisaged that an apparatus may be provided which is able to cover boards with a covering material, cut, saw and form score lines.