Product Handling Assembly

Field of the Invention

The present invention relates to a novel alignment assembly for use in manufacturing, such as biscuit manufacturing, and to methods and apparatus related thereto.

Background

Manufacturing/packaging processes for making foodstuffs, such as biscuits and the like, often produce many lanes of fragile items at high speed. The degree of alignment of the products is not always sufficient to permit full automation, if for example, the items have been disturbed from any initial order by transfers between belts or, for example, by enrobing and/or coating processes.

Particular problems occur with fragile items, such as biscuits, that cannot be handled by conventionally known 'impact based' methods.

In addition it is also a common requirement that, not only must products be in regular rows, but also these rows must be at known positions at known times, to allow correctly phased feeding into subsequent machines and processes, for example, to drop into appropriately positioned packaging, or for synchronisation with coating, decoration or cutting processes.

Conventionally known apparatus for aligning manufactured articles, such as biscuits, usually comprise a plurality of slides and dead plates. These slides a generally known as "dribble boards" and are commonly used in the manufacture and/or packing of

biscuits and comprises a series of laning slides which align the products to suit automatic packing machines. However the performance of such "dribble boards" are subject to variations in friction between the slide and the product, e.g. a biscuit and this can be unpredictable which means that despite improving lane alignment, more often that not they cause further disruptions and misalignment of rows.

Whilst re-alignment and re-phasing into rows can achieved by impacts with gating bars, passing objects over accelerating belts controlled by photocells that adjust speeds according to individual product positions, or by beds of cunningly controlled rollers, such solutions are relatively complex to implement, and often require significant gaps between products in order to operate.

We have now surprisingly found a novel assembly which overcomes or mitigates the disadvantages of known "dribble boards". In particular we have found that the use of a travelling vacuum wave aligner provides row alignment and phasing simply by applying a moving pattern of localised vacuum through an inclined plate onto the base of the product to momentarily and locally decrease the slipperiness of angled surfaces down which product naturally tends to move under gravity.

In this way the product's sliding movement induced by gravity is subtlety modified so as to nudge the product into predictable stable positions, and then keep them in these desired positions as they are moved on through the process, so creating the required alignment and phasing.

Summary of the Invention

According to a first aspect of the invention we provide a dribble board assembly which comprises a longitudinal inclined sliding surface provided with a plurality of longitudinal fluid flow ports which fluid flow ports are adapted to be actuated sequentially.

The assembly of the invention essentially operates on the principle that if a fluid flow port, such as an air flow, e.g. a vacuum, port, is provided part way down a slide, a product positioned on the slide will travel until its front edge reaches the port and it will then be held tight. However, if the fluid flow port, such as an air flow port, e.g. a vacuum port, can be moved down the slide, then the product will follow on just behind it in a series of little jerks. Thus, the moving fluid flow, e.g. a vacuum, effect can be practically implemented by sequentially switching a fluid, e.g. air, flow to successive ports, thus creating a fluid flow wave, e.g. a 'vacuum wave'.

The assembly of the invention is advantageous in that it may align products in a longitudinal direction, augmenting the normal dribble board action of aligning products in a direction that is perpendicular to the longitudinal direction of the apparatus.

The assembly may essentially comprise a conventional dribble board, but provided with the fluid flow ports as hereinbefore described. Thus, for examples the dribble board assembly may be provided with one or more longitudinal channels wherein each channel is provided with one or more fluid flow ports.

It will be understood by the person skilled in the art that the fluid flow applied to the assembly of the invention may comprise a liquid, such as, water or a gas, such as air. This definition should also be construed as meaning the reverse flow of e.g. a gas such as air, so that a vacuum is created. In deed the preferred aspect of the present invention is to provide a vacuum. Furthermore, the fluid flow ports may supply a positive fluid flow to the assembly or alternatively the fluid flow ports may supply a negative flow, i.e. a vacuum. It is within the scope of the present invention for the fluid flow to be a positive fluid flow at a given port and a vacuum at another given port. In one aspect of the present invention the assembly is suitable for the manufacture of biscuits and the like, in which case the fluid flow may be air and/or a vacuum.

In a particular aspect of the invention the fluid flow ports in the assembly, e.g. a packaging assembly are aligned in a linear fashion and the aligned air flow ports are part of a rotary porting unit adapted to route fluid from a fixed point sequentially to a series of openings.

The rotary porting unit as hereinbefore described is novel per se. Therefore, according to another aspect of the invention we provide a rotary porting unit adapted to route fluid, such as air, from a fixed point sequentially to a series of ports which comprises a first plate provided with a linear array of ports and a second plate provided with a circular array of ports and wherein each port in the linear array is connected by a conduit to a corresponding port in the circular array.

Thus, according to a further aspect of the invention we provide a rotary porting module which includes a fluid, e.g. air, flow supply pipe adapted to engage with each of the circular array of ports sequentially such that the supply pipe and the circular array of ports are adapted to rotate relative to each other, and a second array adapted to take the fluid feed between the circular array and the linear array of ports. As hereinbefore described each of the fluid, e.g. air, flow ports may comprise the use of positive flow or of vacuum flow. It will be understood by the person skilled in the art that each of the ports may be described as entry or exit ports on whether the module is operating as a supply of pressure waves or a supply of vacuum waves. The rotatably mounted fluid supply pipe may be a simple rotating arm fed in line with the porting module's axis via a rotating union, for example, as shown in figure 7, or alternatively the gyrating plate system when multiple porting modules are required.

It should also be understood by the person skilled in the art that whilst the supply pipe and the circular rotate relative to each other it is preferred that the supply pipe is rotatable mounted, i.e. is a rotatable arm feed pipe. Thus, whilst the circular array may be rotatable it is preferably adapted to be stationary.

A mechanism to feed into or draw fluid from the rotary porting unit may comprise a gyrating plate mechanism which enables multiple feeds to be simply translated around a whole matrix of porting blocks' circularly spaced input ports. For example, the use of a gyrating plate mechanism can eliminate the need for any rotating seals in the fluid, e.g. air or vacuum, pipe work. A preferred gyration plate embodiment may comprise a motor driving two eccentric arms that are kept in phase by a timing belt, which translate the gyrating plate round in circular arcs. Any number of flexible

pipes from stationary manifolds can then be attached onto the gyrating plate so that each of their outputs describe the circular paths which correspond with the porting module's multiple inlet positions.

Such a gyrating plate mechanism is also novel per se. Therefore, according to a further aspect of the invention we provide a gyrating plate, e.g. for use in assembly as hereinbefore described, which comprises a motor driving at least two eccentric arms that are kept in phase by a timing belt and adapted to be attached to a plurality of flexible pipes from stationary manifolds.

One significant benefit of the design of the present invention is the relatively easy way that the assembly may be scaled up. Typically a manufacturing assembly may have, for example, 15 lanes of biscuits coming down a process line, the design of the present invention uses a standard porting module with spreader elements to adapt it for a given product width and spacings. The use of a single gyrating plate feed greatly simplifies multi-module implementations

Moreover, the phasing and synchronisation of the system to incoming product(s) may be mentioned. Whilst the assembly of the invention may be left 'free running' gathering product into whatever waves are being produced (by setting the gyrating plate speed to reflect the nominal production rate), it is desirable to get the aligning system's row rate to match the incoming product. Also, if any residual row order can be detected on the incoming product then it makes sense to incrementally optimise the phasing of the wave propogation so that preferentially the majority of product starts off near the target position.

In practice, some sensors may be positioned upstream doing trending on the incoming product to extract and quantify any underlying order and then the phase of the gyrator adjusted to best match it. In principle algorithms may be programmed into industrial controllers for this effect.

According to a further aspect of the invention we provide a method of aligning a product in two dimensions which comprises the use of an assembly which comprises a longitudinal inclined sliding surface provided with a plurality of longitudinal fluid, e.g. air, flow ports which fluid flow ports are adapted to be actuated sequentially.

According to a yet further aspect of the invention we provide a method of aligning a product in two dimensions which comprises the use of travelling fluid flow waves, e.g. vacuum waves. Generally speaking the invention provides a conventional dribble board design which uses asymmetric channels in its surface to give lane alignment whilst the fluid flow, e.g. vacuum arrangement of the present invention provides row alignment.

In a yet further aspect of the invention we provide a method which combines the use of travelling vacuum waves in conjunction with sliding motion under gravity e.g. on an inclined surface.

The invention will now be described by way of example only and with reference to the accompanying drawings.

Figure 1 shows five phases of momentarily gripping the leading edge 15 of a product 110 using a travelling vacuum wave 11 as it progresses down a steeply inclined slide plate 10

Fig Ia shows 'holding' Fig Ib shows 'slipping'

Fig Ic shows 'slowing'

Fig Id shows 'holding'

Figure 2 shows five phases of momentarily lifting the trailing edge 25 of a product 110 using a travelling air wave 21 to assist it to slide down and gently inclined slide plate 20

Fig 2a shows 'at rest' Fig 2b shows 'slipping' Fig 2c shows 'slowing' Fig 2d shows 'at rest'

Figure 3 shows a wave containing both vacuum 11 and positive air flow elements 21 holding and releasing at different position within a single wave cycle

Figure 4 shows a the rotary to linear air porting module 40 which takes a feed 48 from a ring of inlet ports 41 and coverts it to a sequential top-to-bottom feed 42 at the output.

Figure 5 shows a number of different formats of output porting depending on the method of manufacture of the porting module, either by bending pipes or more

complex patterns possible if non-round porting can be produced e.g. by stereo lithography.

Figure 6 shows a preferred how the output ports shape 64 can be blended into the round infeed port shape 65, and also illustrates a method of achieving balanced flows through pipes even when their length may have to be different (due to the need for convoluted transactional porting paths between rotary and linear port positions) by increasing the cross sectional area 60 of longer paths 66, the flow can be kept similar

Figure 7 shows a method of providing a single rotating feed 73 to a porting block, with appropriate rotating seals 70

Figure 8 shows a preferred method of feeding multiple porting blocks, using a gyrating plate 84 with multiple flexible vacuum lines 89 from a stationary manifold 86

Figure 9 shows a spreader block 90 that may be mounted at the porting module outfeed face 93 to alter the pitch and width of the vacuum flow to suit a specific product's dimensions

Figure 10 shows a preferred embodiment consisting of matrix of porting modules 40 with a motor 80 driving a gyrating plate 84 whose speed and phase are ideally to match the incoming product via a photocell 101 and a controller 100.

Figure 11 shows a cross section through the preferred embodiment showing integration into adjoining infeed 11 1 and outfeed conveyors 112, and the use of tapered face plate holes 116 to give a self clearing action to minimise any debris build up.

Figure 12 shows the use of the travelling vacuum wave 11 in combination with ridged spreader blocks 120 and face plates 121 so as to in addition allow lane registration.

Figure 13 shows a porting module 40 positioned remotely from the sliding plate, with appropriate piping 132 to a thin deadplate 131

Figure 14 shows a dual rotary-to-linear porting module 143 which has feeds of both air 140 and vacuum 141 and branched piping 142 to route these to different areas of the travelling wave.

Operational description

Principle of operation

Referring to figure 10, lanes of non-aligned product 114 are fed from an infeed conveyor 111 onto the face plate 91.

With no travelling vacuum wave applied, product 1 14 would slide down the plate 91 in an uncontrolled way onto the outfeed conveyor 112 and their position would be further randomised by variability in friction during the sliding.

Figure 1 shows a sequence of snapshots in time which clarify how the application of a travelling wave of vacuum 11 will modify this motion to impose alignment and regular spacing:

Figure Ia shows a vacuum flow 11 holding the leading edge of a product 15, Figure Ib shows the situation a short time interval later when the vacuum wave has been switched to the next orifice, so the product is able to start to slide 14

Figure Ic shows the situation later still when the product that was previously sliding has once again caught up with the moving vacuum wave 11, and so is slowed 12.

Figure Id show the situation later still when the product has stopped once again 13.

If the correct angle is used for the face plate and the vacuum wave advances at the correct rate, then the movement will become substantially smooth as the product resting it front on the travelling vacuum which just marginally slows the movement.

Building blocks

Figure 4 shows a preferred example of the basic building block for the system which is a rotary-to-linear porting module.

It takes a single feed of air flow which is moved round in a circle 41 (vacuum or air dependant on the mode in which the system is to be run) through and converts it to 16 linear ports 42 which it sequentially switched from top to bottom.

For clarity figure 4 includes a second version where the piping is removed for clarity and the inlet and corresponding outlet ports are labelled with the identical letters.

The module itself consists of a circle of inlet ports 41 in a smooth sealing face 45, a length of convoluted transit channel 44 which ends up at one the appropriate position in the linear array of exit ports 42.

The routing of multiple ports is complex, and can be achieved in a number of ways, the simplest is to physically pipe them between two face plates with flexible piping, but the thickness of pipe wall does restrict the positioning of the output porting so that for example they may need to be staggered (figure 5a and 5b).

A preferred way is to use stereo lithography to lay down material around the desired transition channels, as the cross sectional area and shape can be varied along each connection to suit, and the wall thicknesses can be locally minimised to increase packing density where necessary.

Figure 5 includes a number of possible outfeed formats that are possible with 5d giving a progressive changeover between channels.

If the length of a given pipe is longer than others (due to the convolutions required for the routing) then the stereo lithography approach allows a channel's cross sectional area to be increased to compensate for the additional length so that a similar air flow is achieved through all channels Figure 6 illustrates two such channels where the longer channel 66 has an increased cross section 60.

Macros to allow automatic pipe routing to be done within a 3d CAD package can be used for a given number of pipes and a given output configuration, or manual iterative repositioning and flexing of virtual pipe work until a satisfactory design is reached. Once the porting has been defined in CAD multiple standard porting blocks can be fabricated using stereo lithography techniques to create the highly convoluted and variable cross section channels.

Referring to figure 7 the feed 73 to a single porting module 10 can be done by a piped feed to a rotating arm 72 turning about the module's centre, with rotary seals and drive mechanism 71 as necessary.

A number of these modules can then be assembled in a matrix as shown in figure 10 to create a vacuum pulses that are switched down through multiple modules creating a more extensive vacuum wave effect of increased length and over a number of lanes.

If a matrix of porting modules is to be used then preferentially a gyrating plate approach should be used to simplify construction.

Figure 8 shows a preferred gyration plate embodiment with a motor 80 driving two eccentric arms 82 that are kept in phase by a timing belt 81, which translate the gyrating plate 84 mounted on bearings 83 round in circular arcs. Any number or flexible pipes 89 from stationary manifolds 86 can then be attached onto the gyrating plate so that all their outputs describe the circular paths 74 which correspond with the porting module's multiple inlet positions.

Because of the complexity in designing a porting module, in the preferred embodiment a standard size module is used for a range of different sized product, with the adjustment being provided by spreader blocks 90 as shown in figure 9 which can be used to change both the lane and pitch centres to match those required for a given product.

These can also take a staggered pipe output and convert it into a single linear wide slot or the outfeed slot profile may be adapted to suit a given product, for example into a curved slot to work better on the circular edges of round product.

These can be machined conventionally or as a separate stereo lithography element or integrated into the porting module

Referring to figure 10 & 11, in the preferred embodiment the spreader blocks 90 are covered by a final single piece perforated face plate 91 that provides a sliding plate surface which is joint-free and made from material approved for food contact. This can incorporate additional features such as an infeed lip 94 and outfeed lip 95 or laning guides 96 to facilitate transfer on and off the travelling vacuum wave aligner

Configuration

The length of each waveform will need to be sufficient to accommodate each product with a gap between it, and this can be done by scaling the porting module or preferably by using spreading blocks which stretch the wave form to suit.

The gaps between lanes can be changed by scaling the porting module or preferably by using spreading blocks that widen the vacuum slot appropriately, and using corresponding diverging or converging laning guides down the face plate.

Run time

Fixed speed running:

The motor speed is set to a nominal speed which matches the production rate, so one waveform is completed for each row interval.

Product falling within each waveform will be moved to its stable position and so come off at fixed intervals.

A 'once per revolution' output synchronisation pulse from the gyration can be phased to give a 'row leaving' signal for synchronisation of downstream machinery and processes.

Automatic speed and phase matching:

Referring to figure 10 & 11, the photocell 101 detects incoming product rows 114 on the infeed conveyor 111, and over a period of time the controller 100 measures the intervals between these arrival times to establish a good estimate of the underlying row rate and row phasing, and so is able to make a prediction of when the disturbed rows will next reach the travelling wave re-aligner. The speed and phasing of the motor 80 and hence the gyrator plate 84 can then be adjusted to suit the incoming product rate and trimmed in phase to make the best use of any existing row alignment.

A 'once per revolution' output synchronisation pulse 102 from the gyration can be phased to give a 'row leaving' signal as the aligned product 1 15 is placed on the downstream conveyor 112, for synchronisation of downstream machinery and processes.

Other embodiments

The system has been fully described with reference to figure 1 using a vacuum wave to selectively increase friction as hence slow sliding product down a steeply angled plate.

For some applications an alternative option is to use a travelling wave of positive air flow on a less steeply inclined side which momentarily lifts the product and reduces friction and so encourages the product to move under gravity, when otherwise it would remain static.

This can be implemented on the mechanisms previously described by just changing feed from suction to blowing of air.

Positive air flow through the system gives an operational sequence described in figure 2.

Figure 2 shows a sequence of snapshots in time which clarify how the application of a travelling wave of air 21 will create selective this motion to impose alignment and regular spacing:

Figure 2a shows that with no air wave applied under the product 110, it would rest stationary 24 on the face plate 91

Figure 2b and 2c show the situation a short time interval later when the air wave has been switched to the next orifice just under the rear edge of the product 25 reducing friction, so the product is able to start to slide 23

Figure 2d shows the situation later still when the siding product has slid ahead of the moving air wave 21, and so no longer has the reduced friction of an air layer and so grounds 24 on the face plate and is slowed (and optionally stopped).

If the correct angle is used for the face plate, and the air flow rate is adjusted appropriately then the movement will become substantially smooth with the product being continuously nudged forward by the travelling air wave.

In a further embodiment, both vacuum 140 feed and positive air flow 141 can be combined by the use of dual feed porting blocks 143 as illustrated in figure 14, which produces both clamping and freeing actions.

Both vacuum and air feeds are routed to each outlet port, so the transition piping needs to be branched. For clarity figure 14 only shows the channels connected to the active infeed ports. Note that the gyrating plate will need to include an area of sealing face to close off the other input of a branch currently being fed by a vacuum or air source

This dual action is best illustrated by reference to figure 3 which shows a preferred offset between vacuum feed 141 and the air feed 140, when combining the vacuum mode and air modes described in figures 1 and 2 respectively, so that the positive air flow is encouraging the product 110 onward, whist the vacuum flow will prevent any over movement

Sometimes sliding plates are used because space is restricted, for example as a way of getting product from on conveyor to the middle of a cross conveyor 130, where the thinness of a sliding plate minimises the drop that the product experiences during the transfer.

In this case, referring to figure 13 the porting module 40 can be positioned remotely from the sliding plate 131 and connected by appropriately size pipes 132. In addition a photocell and controller can be used to synchronise the feed so as to avoid existing product on the receiving cross conveyor 130.

Referring to figure 12, the spreader block and face plate can also be profiled to give ridges 120 or a valley 123 into which product will laterally slide 124 so providing lateral re-alignment.

This is standard practice in the biscuit industry where such systems are called dribble boards and are used for lane alignment, but the incorporation of travelling vacuum waves into this existing technology provides row alignment in addition to the lane alignment that dribble boards already offer. 0051P.WO.Spec(3)

Table I

Rotary to linear porting

10 steep sliding incline 20 gentle incline 40 module 50 Thick walled pipe

11 Vacuum flow through port 21 Air flow through port 41 Inlet port array (circular) 51 Staggered pipe

Grip reducing air Sterolithography channe

12 slowing 22 cushion 42 Outlet port array (linea) 52 shapes

13 product held 23 Product moved 43 Transitional pipe

14 product released 24 product grounded 44 Transitional channel

15 leading edge 25 trailing edge 45 Sealing face

46 Flexibile pipes

Sterolithography

47 channels

48 Vacuum or air feed

O O

73

> 70 rotary air joints 80 motor 90 Spreader block 100 controller

71 Drive gear 81 Timing belt 91 face plate 101 Photocell o

^■ z. 72 Rotary feed arm 82 Eccentric arms 92 laning ridges 102 Synchcronisation signal

O O 73 Rotating feed 83 bearing 93 outfeed face

^■ o 84 Gyrating plate or flame 94 infeed lip

85 Multiple feed points 95 Outfeed lip

86 Manifold

87 Motor support

88 Gyrator bearing support

89 Multiple flexible pipes

120 spreader block lateral ridges 130 Cross conveyor 140 Air feed

121 face plate lateral ridges 131 Thin dead plate 141 Vacuum feed additional sideways motion against registration

122 edge 132 Extension pipeing 142 Jointed pipeing

123 Valley 133 Remote porting module 143 dual porting module