GB2454166A

GB2454166A - Leaflet collation apparatus

Info

Publication number: GB2454166A
Application number: GB0718835A
Authority: GB
Inventors: Michael Roberts
Original assignee: CHESAPEAKE PLC; Field Group PLC
Current assignee: CHESAPEAKE PLC; Field Group PLC
Priority date: 2007-09-26
Filing date: 2007-09-26
Publication date: 2009-05-06
Anticipated expiration: 2027-09-26
Also published as: GB2454166B; GB0718835D0

Abstract

Apparatus for collating leaflets 26 or the like comprises a lifting wheel 28 with curved slots 32 extending inwardly from the periphery of the wheel 28 for receiving leaflets 26 at a first position and successively lifting them to a stack at a second position above said first position and a slot closure member 38 with a closure surface 40 having at least a portion lying within the outer periphery of said wheel 28 so as to overlap an end portion of said one or more slots 32 during rotation of the wheel 28 thereby preventing leaflets 26 from falling out of said slots 32 as the wheel 28 rotates lifting the leaflets 26 to the second position. A stripper 44 removes the leaflets 26 from the slot 32 at the second position. The stripper 44 may be retractable. Also described are a stack separating mechanism (figures 4A to 4K) and a mechanism for depositing a stack in a tray (figures 7 and 8A to 8F).

Description

LEAFLET COLLATION APPARATUS

The present invention relates to apparatus for collating articles such as leaflets and in particular, but not explicitly, to folded leaflets.

Packaging, for example pharmaceutical packaging, frequently includes a leaflet giving details of the packaged product. These leaflets are usually folded in order to fit within the package. The leaflets are typically cut and folded on specialist machinery produced by companies such as GUK and Vijuk. Typically the eaflets are produced at a different location from the packaging location which means that they must be collated and placed in transit packages, e.g. trays, for transportation to the packaging location. Up to now, the leaflets have been collated in packs by virtue of rollers and belts, but such systems are relatively slow.

The present invention seeks to provide an improved apparatus for collating leaflets and the like which can potentially operate at higher speed.

From a first aspect, therefore, the invention provides apparatus for collating leaflets or the like, said apparatus comprising: a lifting wheel comprising one or more curved slots extending inwardly from the periphery of the wheel for receiving a leaflet at a first position; a stack former for receiving leaflets successively from said lifting wheel at a second position arranged above said first position to form a stack of leaflets; a slot closure member having a closure surface operatively associated with said wheel, said closure surface having at least a portion lying within the outer periphery of said wheel so as to overlap an end portion of said one or more slots during rotation of the wheel thereby preventing leaflets from falling Out of said slots as the wheel rotates lifting the leaflets to the second position; and a stripper for removing said leaflets from said slot at the second position.

Thus in accordance with this aspect of the invention, leaflets are lifted from a first position to a second position using a slotted wheel in cooperation with a slot closure surface. At the desired position, a stripper strips the leaflet from the slot for feeding to a stack former. Such an arrangement allows leaflets to be fed accurately and at relatively high speed to a stack fonner.

Preferably a pair of lifting wheels is provided, with slots on the field being aligned so as to receive a leaflet or the like in aligned slots on the respective wheels.

This will improve the retention of the leaflet in the apparatus. The wheels are preferably driven on a common shaft.

More than one pair of wheels may be provided, allowing for a multi-lane apparatus to be provided. Preferably the lanes are generally parallel to each other.

Preferably multiple pairs of wheels are driven by a common shaft.

More than one slot closure member may be provided. In a preferred embodiment, the apparatus comprises a pair of spaced apart lifting wheels with one, or preferably more than one, slot closure member arranged between the wheels.

Although the slot closure member or members could be placed outside the wheels, it is preferable to arrange the slot closure member or members between the wheels as this will provide better support for the leaflet during its movement with the wheels.

Preferably the or each slot closure member is placed adjacent a respective wheel.

Most preferably at least a portion of the slot closure surface lying within the periphery of the wheel is curved, preferably of a constant radius, that radius being smaller than the radius of the lifting wheel.

The slot closure surface may have a generally straight lead in portion to assist in feeding the leaflet into the slot.

The slot closure surface or at least its lead in portion may be of a low friction e.g. a plastics material to facilitate the leaflet sliding over the slot closure surface as it is lifted in the wheel.

The or each slot is preferably generally helical. Moreover, the or each slot preferably has a flared mouth in order to facilitate the feeding of the leaflets into the slots.

Most preferably, the wall of the slot mouth towards the direction of rotation of the wheel is generally linear so that the leaflet does not curve substantially while being fed into the slot.

Where the slot closure surface has a linear lead in, that lead in preferably extends beyond the linear extent of the slot. This facilitates initial feeding of the leaflet further into the slot.

The opposite wall of the slot mouth is preferably radiused away from the straight surface in order to facilitate funnelling the leaflet into the slot.

The length and width of each slot will be determined by the size of the leaflet or other article handled by the wheel. Typically, however, in a wheel with a nominal diameter of 200 mm, the slot may be 100 to 150 mm long and 3 to 6 mm wide away from its mouth..

Similarly, the number of slots may vary but typically the or each wheel may comprise between 3 and 7, preferably 4 or 5 slots.

Most preferably leaflets are fed to the wheel by means of a conveyor and the slot mouth is arranged so as to be generally coplanar with the outlet from the conveyor to facilitate introduction of the leaflet into the slot. The slot closure surface lead in preferably sits below the plane of the conveyor.

Preferably the conveyor comprises upper and lower conveyor belts which locate the leaflet between them.

In order accurately to position the slots for receiving the leaflets, the wheel is preferably provided with an intermittent, indexing drive rather than a continuous drive. This will also allow the number of leaflets received and transported by the wheel to be counted to ensure that the stack of leaflets produced will have the correct number of leaflets.

As stated above, a stripper is provided for stripping leaflets from the respective slots at the second position at the stacker unit. Most simply, the stripper comprises a stop against which the leaflet abuts during rotation of the wheel such that as the wheel continues to rotate, the leaflet is forced out of the slot into the stacker. After leaving the slot, the leaflet will be urged in the direction of the stacker by the external surface of the wheel as it rotates.

The stripper may comprise a plate or one or more fingers extending between the wheels of the apparatus.

For quality control purposes, it may be desirable to inspect a sample leaflet from time to time. In order to facilitate this, the apparatus may comprise a second stripper arranged downstream of the first stripper in direction of rotation of the wheel, the first stripper being selectively retractable so as to allow a sample leaflet to continue travelling in a slot of the wheel to the second stripper.

This in itself is a novel arrangement, so from a second aspect, the invention provides a collation apparatus comprising a rotary wheel having one or more slots arranged extending inwardly from its periphery for receiving leaflets or the like, a first stripper arranged to remove leaflets from said slots at a first position and a second stripper being arranged to remove leaflets from the slots at a second position downstream of said first position, said first stripper being selectively retractable from its operative position so as to allow said leaflets to pass to said second stripper.

Preferably, the first stripper has a guide surface extending circumferentially around a portion of the wheel in the direction of the second stripper. Most preferably the guide surface is, in the deployed position of the first stripper, arranged to lie within the diameter of the wheel so as to assist in retaining the leaflets within the slots at least over a portion of their transit path to the second stripper.

The first stripper may be retractable from its operative position in any suitable manner. In a simple embodiment, however, the first stripper may be retracted in a linear manner by a suitable linear actuator.

The second stripper can, for example, merely be a bar, plate or the like against which the leaflets abut so as to be stripped from the wheel.

The stacker preferably comprises a surface for receiving leaflets from the wheel and a moveable backstop against which the leaflets are stacked. Preferably the guide surface is substantially horizontal.

The backstop is preferably freely moveable on a guide, being moved rearwardly by the leaflets as they are fed into the stack from the wheel.

As it is not practical to stop the apparatus when a stack of predetermined size has been produced, the apparatus preferably further comprises a stack separator which allow a second stack to be started while a first stack is still on the apparatus.

Preferably the stack separator comprises a pair of separating elements which are introduced at one end of a stack after a predetermined number of leaflets have been added to the stack (which can be detennined from the indexed rotation of the wheel).

Most preferably the separating elements are raised and lowered vertically, for example by actuators such as pneumatic pistons.

The advant4ge of providing vertically movable stack separators is that it allows multiple lanes of collation apparatus to be provided closely adjacent to one another. This is advantageous in its own fright, so from a further aspect, the invention provides a leaflet collation apparatus comprising a moveable backstop against which a stack of leaflets may be formed and a stack separating mechanism comprising first and second elements which are movable vertically so as to delimit one end of the stack and start a subsequent stack.

Preferably the stack separator comprises a first element, remote from the wheel which is drivable away from the wheel so as to move the formed stack and backstop away from the wheel to a second location where the stack may be removed and a second element which, when the first stack is separated, acts as a backstop for a subsequent stack.

As with the backstop, this second element is freely movable on a guide such that it too is pushed away from the wheel by the accumulating stack.

Any suitable drive mechanism may be provided for the first separator element. Preferably, the first separator element is belt driven.

Preferably means are provided on the first separator element for cooperation with the backstop for returning the backstop to a stack forming position after the stack of leaflets has been removed from between the backstop and the first element.

In a simple embodiment, cooperating formations may be formed on the first element finger and the backstop. Preferably means are provided to retract the first element from an operative position, move the first element to a position adjacent the backstop and then extend the first element into engagement with the backstop.

When the first separator element and backstop have been moved back to a position in which the first element is adjacent the second element,, the first and second elements may be retracted in order to allow the stack once more to be formed against the backstop.

The backstop and first separating element are preferably in the form of plates to provide support to the leaflets of the stack over a relatively large area.

From a yet further aspect the invention provides leaflet collation apparatus comprising a backstop against which a stack of articles is formed and first and second separator elements deployable such as to delimit one end of the stack and start a second stack of leaflets, said first separating element being a driven element which is drivable to separate the first stack from the subsequent forming stack and which further comprises means for cooperating with the backstop to return it to a stack forming position after the stack has been removed from between the backstop and the first separating element.

This latter aspect of the invention may be applicable to arrangements in which the elements are deployed in directions other than vertical.

The collated stack of leaflets between the backstop and first separator element may be removed by any suitable means. Such means may comprise a gripper which grips respective ends of the stack.

Preferably the gripper comprises gripper fingers and where the backstop and first separating element are in the form of plates the plates may have slots to accommodate the gripper fingers. The gripper may also be provided with a vacuum supply in order to assist in retaining the leaflets. This is particularly useful where long stacks are being moved.

The stacks of leaflets are normally stacked into trays. Normally the trays have flaps which, when the stack is placed in the tray, are folded over the leaflets.

In a preferred embodiment of this invention, means are provided for opening the flaps of the tray so as to facilitate insertion of the stack of leaflets into the tray.

Preferably such means comprises a pair of arms which are lowered between the flaps and moved apart in order to splay the flaps. Most preferably the arms have an outwardly flared upper portion so as to further assist in guiding the stack of leaflets being placed into the tray.

A potential problem with such stack placement is that when the stack gripper is removed from the tray, it may inadvertently displace leaflets from the stack. In accordance with a yet further aspect of this invention the tray flap opener is moveable to a position which it overlies the deposited stack of articles so as to retain the articles in the tray while the gripper is removed.

From a further aspect, therefore, the invention provides apparatus for depositing a stack of articles in a tray having flaps on an open face of said tray, said apparatus comprising a pair of flap opening arms and drive means for moving the arms to a first position between the flaps of the tray, to a second position which the arms are moved apart to open the flaps of the tray and allow a stack of articles to be introduced into the tray and to a third position in which the arms are moved together to engage over a stack of articles deposited in the tray.

The drive means may comprise means for moving the arms away from and towards one another by suitable actuators, for example pneumatic cylinders.

A preferred embodiment of the invention will now be described by way of example only with reference to the accompanying drawings, in which: Figure 1 is a plan view of a multi-lane apparatus in accordance with the invention; Figure 2 is a detail of the apparatus of Figure 1; Figure 3A is an enlarged view of Figure 2 showing detail thereof more clearly; Figure 3B shows a modified detail of Figure 3A; Figures 4A to 4K show stages in the formation of stacks in the apparatus of Figure 1; Figure 5 shows a schematic sectional view of a stack gripper; Figure 6 shows an end view of the stack gripper of Figure 5; Figure 7 shows a detail of the tray opening mechanism of the apparatus of Figure 1 in more detail; and Figures 8A to 8F show the sequence of deposition of stacks in a tray.

Figure 1 shows schematically an apparatus 2 in accordance with the invention. The apparatus broadly comprises four leaflet collation units 4 arranged side by side in a parallel manner, a gripper unit 6 for removing stacks of leaflets from the collation units 4 and a tray filling section 8 in which stacks of leaflets are filled by the gripper unit 6 into trays 10.

With reference now to Figures 1 and 2, each leaflet collation unit comprises an in-feed conveyor 20 comprising upper and lower feed belts 22,24. Two, spaced apart parallel in-feed conveyors 20 may be provided per collation unit 4, receiving folded leaflets 26 from a leaflet cutting and folding unit (not shown).

Each collation unit 4 further comprises a pair of lifting wheels 28 mounted on a common shaft 30. As shown in Figure 1, the wheels of the various units 4 may be mounted on the same shaft 30.

Each wheel 28 comprises five generally helical slots 32 extending inwardly from the periphery of the wheel 28. Each slot 32 has a flared mouth having a generally linear portion 34 and a radiused opposed portion 36. The slots 32 of each wheel pair are aligned.

Arranged between each pair of wheels 28 is a pair of spaced apart slot closure members 38. Respective slot closure members 38 are positioned closely laterally adjacent the respective wheels 28.

Each slot closure member has an arcuate slot closure surface 40 which lies within the perimeter of the wheel 28 so as to overlap the ends of the wheel slots 32, as is best shown in Figure 3. The slot closure surface 40 has a linear lead-in surface 42 which is generally coplanar with, or lies just below (e.g. 3-5 mm below), the plane of the in-feed conveyor 20 so as to assist in guidance of the leaflets 26 into the slots 32 of the wheels 28.

As can be seen from Figure 3B, the slot closure member 40 may be mounted on a support plate 41. The slot closure member 40 may therefore be made of any desirable material e.g. a plastics material e.g. PTFE, to give low frictional properties to facilitate movement of the leaflets 26 around with the wheel 28.

Although the slot closure surface 40 of the slot closure member is shown as flat across its width, it need not be and it can be curved or rounded, provided it serves the requisite purpose.

In the embodiment of Figure 3A the lead in surface 42 does not extend beyond the linear portion 34 of the slot. Shown in dotted lines, however, is an alternative slot closure surface 40' with a much longer lead in 42'. This allows the leaflet 26 to be introduced further into the slot 32 by the conveyor 22.

At the upper end of the slot closure surface 40, a leaflet receiving surface 43 is provided to receive leaflets 26 as they are formed into stacks S. The surface may be a solid surface or provided for example by a pair of spaced apart rails or the like.

Also arranged between the wheels 28 of each wheel pair is a leaflet stripper 44. In the preferred embodiment, the stripper 44 comprises a pair of stripper fingers 46 mounted on a common support 48 for movement by a pneumatic or other actuator 50. Each stripper finger 46 comprises an abutment surface 52 arranged opposite the leaflet receiving surface 42 and a depending section 54. The distal end 58 of the stripper 46 is formed as a curved surface 60 which, when the stripper is retracted to a position as shown in Figure 4B, lies within the perimeter of the wheel 28. This surface 60 continues into the depending section 54 of each finger 46.

The stripper 44 is retractable to allow a sample leaflet to bypass the stack for inspection as will be described further below. To allow collection of a sample, a second stripper 62, for example in the form of a plate or fingers, is provided between the wheels 28 downstream of the first stripper 44.

The collation unit further comprises a stack backstop 70 and a stack separator 72.

As shown in Figures 1 and 2 the backstop 70 is freely mounted, through a carriage 74, for sliding movement along a pair of guide rails 76. The backstop 70 comprises a forwardly extending, L-shaped arm 78. The upstanding limb 80 of the arm 78 is formed with a series of vertical slots for a purpose which will be described further below.

The stack separator 72 comprises a first element 82 and a second element 84.

The first element 82 is generally L-shaped having an upstanding limb 86 which, like the upstanding limb 80 of the backstop 76 is formed with vertical slots. The first element 82 is mounted, at its proximal end 88, on an actuator 90, more particularly a pneumatic actuator 90 which is mounted on guide rail 74 through a carriage 92. The carriage 92 is provided with a coupling 94 to couple to a toothed drive belt 96. As shown in Figure 1, this drive belt 96 is driven by a servo motor/gear box 98 mounted towards the front of the unit. As can be seen in Figure 1, the motors 98 for each respective drive belt 96 may be offset so as to allow the respective collation units 4 to be placed more closely together.

The first element 82 is also provided with a projection 96 on its upper surface for a purpose which will be described further below.

The second separator element 84 is mounted on a further pneumatic actuator 100. This actuator 100 is mounted for sliding movement on the guide rails 74 through a carriage 102.

Operation of the apparatus as described thus far will now described with reference to Figure 1 to Figures 4A to 4K.

In Figure 2, a collation unit 4 is shown as empty, ready to receive a first leaflet 26. The wheels 28 of each unit are indexed by a drive motor (not shown) in an intermittent manner and synchronised with the speed of the in-feed belts 20 such that the wheels 28 are stationary in the position shown in Figure 2 as the leaflet 26 is fed from the conveyor 20 into a slot 32. The wheels 28 are indexed to bring the next slot 32 into alignment with the end of the conveyor 20 once the leaflet 26 has been fi.illy received within the slot 32.

As the wheel 28 is indexed, the leaflet 26 moves round with the wheel 28 and is prevented from falling out of the slot 32 by virtue of the curved slot closure surface 40 of the slot closure member 38. Thus, as the wheel 28 is indexed, the leaflet 26 is lifted from the in-feed conveyor 20 in a series of indexing movements.

During the second indexing movement, the leaflet 26 will come into abutment with the abutment surface 52 of the first stripper 44 and be is pushed down and out of the slot 32 by the abutment surface 52. Due to the curvature of the slot 32, the leaflet 26 is pushed to the left in the sense of the Figures so as to rest in an upright location on the receiving surface 43. The first leaflet 26 received on that surface 43 is prevented from toppling over by virtue of engaging with the backstop 70. As the wheel indexing continues, more and more leaflets 26 are deposited onto the receiving surface 43, causing the backstop 70 to move backwardly as shown in Figure4A.

At some point during the stacking operation, it may be desirable to obtain a sample for quality control purposes. The mechanism for achieving this is best illustrated in Figures 4B through 4D. When a sample leaflet is to be taken (which can be instigated automatically or manually), the stripper 44 is retracted as shown in Figure 4B by means of the actuator 50. This moves the abutment surface 52 of the stripper 44 out of engagement with the wheel 28 which means that a leaflet 26A to be sampled remains within a slot 32 rather than being ejected onto the receiving surface 43. As can be seen in Figure 4B, the curved surface 60 of the stripper 44 in effect continues the curved surface 40 of the slot closure member 38 so as to prevent the leaflet 26A falling out of the slot 32 during its upward travel.

At the end of the indexing movement, the first stripper 44 is once more extended such that its abutment surface 52 once more lies between the wheels 28.

That movement assists in pushing the sample leaflet 26A further into its respective groove 32. During the next indexing movement of the wheel 28, the next leaflet 26 will once more be deposited in the growing stack S while the sample leaflet 26A will move around the wheel. Further indexing movements of the wheel 28A will bring the sample leaflet 26A into contact with the second stripper 62 which removes the leaflet 26A from the slot 32 for inspection, as shown in Figure 4D.

Figure 4D also shows the first stage in the stack separation mechanism. In particular, when the requisite number of leaflets 26 has been received on the receiving surface 43, the stack separator 72 is deployed. In particular, the first and second separator elements 82,84 are deployed together upwardly by their respective actuators 90,100 so as to delimit one end of the stack S. Once the separating elements 82,84 are deployed, the driven element 82 is driven rearwardly by the belt drive 96 so as to push the stack S and the backstop 70 away from the wheels 28 to a stack removal position as shown in Figure 4E. The stack S is supported between the surfaces 80,86 on the backstop and first separator element respectively. At the same time, a subsequent stack S' starts to form at the second element 84, which is pushed backwardly by the leaflets 26 joining the stack S'.

As shown in Figure 4F, the stack S is then removed from between the surfaces 80,86 by the gripper unit 6 (as will be described in further detail below).

Once this occurs, it is necessary to return the backstop 70 to a position in which it will receive the subsequent stack S'. In order to achieve this, the first separator element 82 is first retracted by its actuator 100 as shown in Figure 4G. The element 82 is then moved rearwardly by drive belt 96 so as to underlie the backstop finger as shown in Figure 4H. The first separator element 82 is then raised to underlie the backstop finger 80. The backstop finger 80 is provided with a recess (not shown) into which extends the projection 96 formed on the separator element 82.

This acts to key the two backstop 70 and element 82 together. The first separator -12 -element 82 is then moved to the nght as shown in Figure 4J, bringing the backstop with it, until the first separator element 82 lies adjacent the second separator element 84 forming the backstop for the stack S'. Both separating elements 82, 84 are then vertically retracted by the actuators 90,100 as shown in Figure 4K. This allows the stack S' to fall back slightly against the backstop finger 80, against which the stack S' then continues to be formed. As a final stage, the separating elements 82, 84, are returned to the position shown in Figure 2 ready to be deployed when the stack S' is to be separated. This sequence of events is then repeated.

As stated above, each stack S of leaflets is removed from the receiving surface 78 by a gripper unit 6.

As shown in Figure 1, the gripper unit 6 is mounted such that it may take stacks of leaflets from any of the collation units 4 within the apparatus. The gripper unit 6 comprises a gripper head 110 which is mounted for transverse movement across the collation units 4 on a first linear actuator 112. That actuator 112 is mounted for longitudinal movement relative to the units 4 on further linear actuators 114. The head is also comprises a further actuator 116 for vertical movement.

The gripper head 110 comprises a pair of slotted plates 120 mounted on a base 122 through actuators 124. As shown in Figure 6, the slotted plates 120 have fingers 126 which are able to move between the slots provided in the upstanding limbs 80, 86 of the backstop 70 and the first separating element 82 in order to grip the ends of the stack S of the leaflets 26. The moveable gripper plates 120 allow the gripper to consolidate the stack S of leaflets 26 before it lifts them from the receiving surface 78. It also allows one head 110 to be used to accommodate various lengths of stacks S. The gripper head 110 is moved by means of the actuators 112,114 to the appropriate collation unit 4 to remove a stack S of leaflets 26 therefrom, whereupon the head 110 is lowered towards the collation unit 4 to gather the stack S, and then retracted vertically and moved to the tray filling location 8 by the respective actuators 112,114. In order better to support the stack S of labels 26 between the plates 120, a vacuum may be applied to the stack S through the undersurface 126 of the gripper head 110 in a known manner.

-13 -Once at the tray filling location 8, the stack S is loaded into a tray 10. As shown in Figure 8A, the tray 10 comprises a pair of flaps 130 which will eventually be closed over the top of the tray 10. However, these flaps 130 may interfere with loading of stacks S into the tray 10. Thus, a flap opening mechanism 132 is provided at the tray filling location 8.

As shown in Figure 7, this mechanism 132 comprises a pair of arms 134. As shown in Figure 8A, each arm 134 has an outwardly angled upper end 136 and a vertical lower end 138. The flap opening mechanism 132 is mounted on a vertically movable head 140. The arms 134 are movable towards and away from one another by means of actuators 142 provided on the head 140.

In order to open the tray flaps, the arms 134 are first moved towards one another above the tray, as shown in Figure 8A. The head 140 is then lowered so as to drop the vertical arm sections 138 between the flaps 30 as shown in Figure 8B.

The arms 134 are then moved apart in order to spread the flaps 130. The gripper head 110 is then brought into position above the tray 10 as shown in Figure 8C and then lowered as shown in Figure 80 such that the stack S of leaflets 26 is deposited in the tray 10. It will be understood that the flared portions 138 of the arms 134 will assist in guiding the stack S of leaflets 26 during deposition.

Once the stack S of leaflets 26 has been deposited, the arms 134 are once more moved towards each other as shown in Figure 8E so that the vertical sections 138 of each ann 134 overlie upper edge regions of the deposited stack S whereupon the gripper head 110 may be removed vertically as shown in Figure 8F without any danger of the head 110 dislodging the stack S as it is withdrawn.

Once the tray 10 has been filled, it may be pushed out on to a conveyor 150 by a pusher unit 152 for subsequent handling. -14-

Claims

Claims 1. Apparatus for collating leaflets or the like, said apparatus comprising: a lifting wheel comprising one or more curved slots extending inwardly from the periphery of the wheel for receiving a leaflet at afirst position; a stack former for receiving leaflets successively from said lifting wheel at a second position arranged above said first position to form a stack of leaflets; a slot closure member having a closure surface operatively associated with said wheel, said closure surface having at least a portion lying within the outer periphery of said wheel so as to overlap an end portion of said one or more slots during rotation of the wheel thereby preventing leaflets from falling out of said slots as the wheel rotates lifting the leaflets to the second position; and a stripper for removing said leaflets from said slot at the second position.
2. Apparatus as claimed in claim 1 comprising a pair of lifting wheels is provided, with slots on the wheels being aligned.
3. Apparatus as claimed in claim I or 2 comprising more than one pair of wheels.
4. Apparatus as claimed in any preceding claim comprising a pair of spaced apart lifting wheels with one or more associated slot closure members.
5. Apparatus as claimed in claim 4 wherein the slot closure member or members is or are arranged between the wheels.
6. Apparatus as claimed in any preceding claim wherein at least a portion of the slot closure surface lying within the periphery of the wheel is curved.
7. Apparatus as claimed in claim 6 wherein the surface is of a constant radius, that radius being smaller than the radius of the lifting wheel. -15-
8. Apparatus as claimed in any preceding claim wherein the slot closure surface comprises a generally straight lead in portion.
9. Apparatus as claimed in any preceding claim wherein at least a lead in portion of the slot closure member is of a low friction e.g. a plastics material.
10. Apparatus as claimed in any preceding claim wherein the or each slot is generally helical.
11. Apparatus as claimed in any preceding claim wherein the or each slot has a flared mouth.
12. Apparatus as claimed in any preceding claim wherein the wall of the slot mouth towards the direction of rotation of the wheel is generally linear.
13. Apparatus as claimed in claim 12 as dependent directly or indirectly on claim 8 wherein the linear slot closure lead in portion extends beyond the linear extent of the slot.
14. Apparatus as claimed in claim 12 or 13 wherein the opposite wall of the slot mouth is radiused away from the straight surface.
15. Apparatus as claimed in any preceding claim comprising between 3 and 7 slots or more narrowly 4 or 5 slots.
16. Apparatus as claimed in any preceding claim comprising a conveyor for feeding leaflets to the wheel and wherein the slot mouth is arranged so as to be generally coplanar with the outlet from the conveyor.
17. Apparatus as claimed in claim 16 wherein the slot closure surface lead in sits below the plane of the conveyor.
18. Apparatus as claimed in any preceding claim wherein the wheel or wheels is or are provided with an intermittent, indexing drive.
19. Apparatus as claimed in any preceding claim wherein the stripper comprises a stop against which the leaflet abuts during rotation of the wheel.
20. Apparatus as claimed in claim 19 wherein the stripper comprises a plate or one or more fingers extending between lifting wheels.
21. Apparatus as claimed in any preceding claim comprising a second stripper arranged downstream of the first stripper in direction of rotation of the wheel, the first stripper being selectively retractable so as to allow a leaflet to continue travelling in a slot of the wheel to the second stripper.
22. A collation apparatus comprising a rotary wheel having one or more slots arranged extending inwardly from its periphery for receiving leaflets or the like, a first stripper arranged to remove leaflets from said slots at a first position and a second stripper being arranged to remove leaflets from the slots at a second position downstream of said first position, said first stripper being selectively retractable from its operative position so as to allow said leaflets to pass to said second stripper.
23. Apparatus as claimed in claim 21 or 22 wherein the first stripper has a guide surface extending circumferentially around a portion of the wheel in the direction of the second stripper.
24. Apparatus as claimed in claim 23 wherein the guide surface is, in the deployed position of the first stripper, arranged to lie within the diameter of the wheel.
25. Apparatus as claimed in any of claims 21 to 24 wherein the first stripper is retracted in a linear manner by a linear actuator.
26. Apparatus as claimed in any of claims 21 to 25 wherein the second stripper comprises a bar, plate or the like.
27. Apparatus as claimed in any of claims 23 to 26 wherein the guide surface is substantially horizontal.
28. Apparatus as claimed in any preceding claim wherein the stacker comprises a surface for receiving leaflets from the wheel and a moveable backstop against which the leaflets are stacked.
29. Apparatus as claimed in claim 28 wherein the backstop is freely moveable on a guide, so as to be movable rearwardly by the leaflets as they are fed into the stack from the wheel.
30. Apparatus as claimed in any preceding claim further comprising a stack separator which allows a second stack to be started while a first stack is still on the apparatus.
31. Apparatus as claimed in claim 30 wherein the stack separator comprises a pair of separating elements which are introduced at one end of a stack after a predetermined number of leaflets have been added to the stack.
32. Apparatus as claimed in claim 31 wherein the separating elements are raised and lowered vertically.
33. A leaflet collation apparatus comprising a moveable backstop against which a stack of leaflets may be formed and a stack separating mechanism comprising first and second elements which are movable vertically so as to delimit one end of the stack and start a subsequent stack.
34. Apparatus as claimed in any of claims 30 to 33 wherein the stack separator comprises a first element, remote from the wheel which is drivable away from the -18-wheel so as to move the formed stack and backstop away from the wheel to a second location where the stack may be removed and a second element which, when the first stack is separated, acts as a backstop for a subsequent stack.
35. Apparatus as claimed in any of claims 30 to 34 further comprising means on the first separator element for cooperation with the backstop for returning the backstop to a stack forming position after the stack of leaflets has been removed from between the backstop and the first element.
36. Apparatus as claimed in claim 35 wherein cooperating formations are formed on the first element finger and the backstop.
37. Apparatus as claimed in any of claims 34 to 36 comprising means are for retracting the first element from an operative position, move the first element to a position adjacent the backstop and then extend the first element into engagement with the backstop.
38. Leaflet collation apparatus comprising a backstop against which a stack of articles is formed and first and second separator elements deployable such as to delimit one end of the stack and start a second stack of leaflets, said first separating element being a driven element which is drivable to separate the first stack from the subsequent forming stack and which further comprises means for cooperating with the backstop to return it to a stack forming position after the stack has been removed from between the backstop and the first separating element.
39. Apparatus as claimed in any of claims 27 to 38 comprising a gripper for removing a collated stack of leaflets from between the backstop and first separator element.
40. Apparatus as claimed in claim 39 wherein the gripper comprises gripper fingers and where the backstop and first separating element are in the form of plates the plates may have slots to accommodate the gripper fingers.
41. Apparatus as claimed in claim 39 or 40 wherein the gripper is provided with a vacuum supply.
42. Apparatus as claimed in any preceding claim further comprising means for opening the flaps of a tray so as to facilitate insertion of a stack of leaflets into the tray.
43. Apparatus as claimed in claim 42 wherein such means comprises a pair of arms which are lowered between the flaps and moved apart in order to splay the flaps.
44. Apparatus as claimed in claim 43 wherein the arms have an outwardly flared upper portion.
45. Apparatus for depositing a stack of articles in a tray having flaps on an open face of said tray, said apparatus comprising a pair of flap opening arms and drive means for moving the arms to a first position between the flaps of the tray, to a second position which the arms are moved apart to open the flaps of the tray and allow a stack of articles to be introduced into the tray and to a third position in which the arms are moved together to engage over a stack of articles deposited in the tray.