More particularly, the present invention relates to a device for grouping a pre- determined number of articles and feeding the grouping downstream at a pre- determined pitch. The invention also relates to a method of metering articles.

Known metering devices generally comprise opposed reciprocating clamping devices which engage the sides of a predetermined number of articles and accelerate the articles to separate them away from an in-feed stream thereof. An example of such a device is disclosed by European Patent Application 0708028 to the Riverwood International Corporation.

Some known devices are generally limited to the metering of a single article type, grouping and pitch, or alternatively require a significant amount of machine downtime to change these variables. Furthermore, the throughput of such devices is intrinsically limited by their design.

The present invention seeks to overcome or at least mitigate the problems of the prior art.

One aspect of the invention provides a metering device for selectively separating at least one article from an infeed stream of such articles comprising an article conveying means including one or more lugs mounted on an endless track, wherein cam means causes the or each lug to move from a retracted position to a deployed position interposed between the articles at a desired location at an infeed end of the device and the or each lug is caused to form a grouping containing a predetermined number of articles with a predetermined spacing between adjacent groupings. Preferably, the lug is accelerated by drive means to form the at least one article into the grouping to achieve the desired spacing between adjacent groupings.

Beneficially, the device of the present invention is capable of switching from one configuration of grouped articles to another for loading into different carton types or sizes with minimum downtime, for example between adjacent groupings.

According to an optional feature of this aspect of the invention the lug may comprise an elongate member. Preferably, the elongate member may be slidably mounted on a slide member. More preferably, the elongate member may be releasably secured to a mounting member slidably mounted on the slide member.

Even more preferably the cam means comprises a cam follower provided on the mounting member, arranged to follow a fixed cam profile.

According to another optional feature of this aspect of the invention a plurality of mounting members may be provided at fixed intervals along the endless track.

Preferably, the or each elongate member may be detachably connected to be removed from their respective mounting members and secured to alternative mounting members, thereby to adjust the spacing and/or size of articles contained in the grouping.

According to another optional feature of this aspect of the invention for each grouping there may be provided a leading and trailing lug to ensure the articles remain tightly packed.

According to another optional feature of this aspect of the invention once the required groupings and pitches have been formed, the cam means may cause the or each lug to retract to a stowed position.

According to a further optional feature of this aspect of the invention the rate of article infeed may be determined by a star-wheel arrangement at an upstream end of the article conveying means.

According to another optional feature of this aspect of the invention the article conveying means may permit the articles to be accelerated by the device.

According to another optional feature of this aspect of the invention the device may further comprise control means to control the speed of the or each lug thereby to control the number of articles in each grouping and/or the spacing between adjacent groupings.

Preferably, the control means may comprise means for receiving information regarding the speed of cartons at the infeed end of the article conveying means.

According to another optional feature of this aspect of the invention the control means may comprise a manual input means.

According to a further optional feature of this aspect of the invention the control means may comprise a sensor arranged to measure the speed of articles at the infeed end of the article conveying means.

According to yet another optional feature of this aspect of the invention the device may have a sensor arranged to measure the speed of the lug or lugs.

According to still further another optional feature of this aspect of the invention the control means may vary the speed of the lug or lugs to lie within the range plus or minus 1-30% of the speed of the articles at the infeed end of the article conveying means.

A second aspect of the invention provides a controller for controlling the speed of a lug in a device, the controller comprising a central processor, a manual input means, and separate means controlled by the central processor for individually positioning and/or relocating the or each lug and the endless track. Preferably, the controller may have an article feed means in the form of a star wheel, the controller controlling the speed of rotation of the star wheel. More preferably, the controller may control a motor which rotates the star wheel.

According to an optional feature of the second aspect of the invention the speed of supply of articles may be alterable as required depending on the size or type of cartons at the infeed end of the machine.

According to another optional feature of the second aspect of the invention the relative positions and state of motion of each of the movable components may be sensed using individual sensors and transmitted to the controller.

A third aspect of the invention provides a method of metering articles into groupings having a predetermined pitch comprising the steps of: continuously feeding the articles into the infeed end of an article conveying means at a known rate; synchronising a elongate member such that it is interposed between the articles downstream thereof so as to form the grouping; accelerating the elongate member and group such that the predetermined pitch between adjacent groupings is achieved. Preferably, the speed of the articles at the infeed end of the article conveying means may be received by control means which controls the speed of the elongate member.

According to an optional feature of the third aspect of the invention the speed of the articles may be entered manually.

According to another optional feature of the third aspect of the invention the speed of the articles may be sensed automatically.

Exemplary embodiments of the present invention are now described, by way of example only, with reference to the drawings in which: FIGURE 1 is a perspective view of a lug assembly according to an embodiment of the invention; FIGURE 2 is a perspective view of an alternative lug assembly according to a second embodiment of the invention;

FIGURE 3 is a perspective view of a mounting assembly on which the lug assemblies of Figure 1 or Figure 2 may fit; FIGURE 4 is a bottom view of a cam and follower arrangement according to a first embodiment of the invention; FIGURES 5A and 5B are perspective and plan views respectively of one configuration of the device according to an embodiment of the invention; FIGURE 6 is a flow diagram of a controller suitable for operating a device in accordance with the present invention; FIGURES 7A and 7B are further perspective and plan views respectively of another configuration for use with a different grouping; and FIGURES 8A and 8B are perspective and plan views respectively of a further configuration of the device for a different article grouping.

Referring to the drawings there is shown in Figures 5A and 5B a metering device for selectively separating at least one article"A"from an infeed stream of such articles comprising an article conveying means 38 including one or more lugs mounted on an endless track 36, wherein cam means 26,34 causes the or each lug to move from a retracted position to a deployed position interposed between the articles at a desired location at an infeed end of the device and the or each lug is caused to form a grouping containing a predetermined number of articles with a predetermined spacing between adjacent groupings.

Referring now to Figure 1, there is shown a lug assembly 10 for use with the device of the present invention, preferably comprising a body portion 12 having an elongate member 18 projecting therefrom. The body portion preferably includes mounting means which, in this embodiment, comprises a recess 16 and a bore 14 extending from top to bottom through the body portion 10 in which some form of bolt or quick release

fastener (not shown) may fit. The free end of the member 18 preferably terminates at a point 20. In this embodiment, one side face of the member 18 is co-extensive with a side face of the body 12.

In other embodiments, the elongate member may be positioned to be co-extensive with the opposing side face of the body 12.

Referring now to Figure 2, there is shown a variant of the lug assembly 1 Oa which again comprises a body portion 12a having mounting means 14a and 16a provided thereon.

In this variant of the assembly I Oa however, the member 18a is mounted substantially centrally on the body portion 12a. The different positions of the elongate member with respect to the body portion provides accurate positioning of the elongate members for different article groupings.

Turning now to Figure 3, there is shown a device for moving the lug assembly between retracted (or stowed) position and an operative position. In this embodiment there comprises a slide assembly 21, including a mounting member 22 and a pair of slide rods 30 secured at their ends to connectors 32. The connectors 32 are connected to an endless track described below. In this embodiment, the mounting member 22 is journalled onto the slide rods 30 to permit slidable movement in the directions indicated by the arrows X.

The mounting member 22 further preferably comprises co-operating mounting means to secure lug assembly 10 thereto. In this embodiment, the mounting means is provided by raised portions 24 which cooperate with recess 16 on the lug assembly, and an aperture 28 in which a bolt or some form of quick release fastener may be releasably secured in co-operation with aperture 14 of the lug assembly 10, to prevent relative movement therebetween. In alternative classes of embodiment, other known mounting means such as a suitable clip may be used.

A cam arrangement is provided in this embodiment for guiding the mounting means 22 through the working reach. The cam arrangement is provided with a cam follower 26

projecting from the underside of the mounting member 22, and co-operating with a cam profile 34 (Figure 4). In Figure 4 there is shown a bottom view of a plurality of slide assemblies 21 hingedly connected one to the next as part of an endless track 36 with, in some cases, lug assemblies 10,1 Oa mounted thereon. A fixed cam profile 34 is provided under the slide assemblies. In this embodiment cam followers 26 fit into the cam profile, and as the endless track 36 advances in a direction Y, the cam track 34 causes the slide members 22 hence the lug assemblies 10,1 Oa to move in a direction X such that the elongate members 18 are moved from a retracted position substantially overlying the endless track 36 to a deployed position in which the elongate members 18 project over the article conveying means 38.

Referring now to Figures 5A and 5B, the device 40 including lug assemblies 10,10a and slide members 21 is shown in operation. It can be seen that, for the purposes of clarity, Figure 5A, does not show the slide assemblies 21 along the entire extent of the endless track 36. The endless track is driven by suitable drive means (not shown) such as a servo motor.

In one class of embodiments, the slide assemblies 22 are grouped so that there comprises pairs of slide assemblies 22, separated by groups of four slide assemblies 22.

This allows different pitches to be used, for the various group sizes.

A continuous stream of articles"A"progresses downstream from an infeed end 42 of article conveying means 38 at a velocity Z. In this embodiment, the articles are bottles, however in alternative embodiments, the articles may be cans or paperboard"bricks", for example. The flow of articles is preferably controlled by a star wheel assembly (not shown) which feeds the articles at a known rate, although in alternative classes of embodiment, other suitable known flow controller may be used.

The article conveyor is a variable speed conveyor controlled by the controller.

Therefore, to increase the flow rate, for example for a larger group of articles, the control means causes the star wheel and article conveyor to speed up.

As the articles"A"progress downstream one of the plurality of elongate members 18 will become interposed between the pairs of adjacent articles"A"under the influence of the cam assembly. Advantageously for each grouping G I, a leading elongate member 18b is also introduced downstream of the grouping, prior to the interposition of a trailing elongate member 18a, thereby ensuring that the articles"A"remain tightly packed within the grouping G1.

The downstream velocity Y of the elongate members 10,1 Oa is generally greater than the downstream velocity 2 of the articles"A". Therefore, when elongate member 18a becomes interposed, the articles"A"downstream of the interposition point are accelerated, such that the pitch PI between adjacent groupings Gl is achieved. In this embodiment, each grouping Gl comprises six articles in a 3 x 2 configuration. At position 44, the article conveyor means 38 preferably therefore permits the article groupings G I to be accelerated in a substantially unhindered manner which is controlled by the controller. To achieve this, the article conveyor means 38, may at this point, consist of freely rotating rollers, or similar suitable means known in the art.

To maintain tight grouping in a transverse direction, adjustable guides (not shown) arranged either side of the articles, parallel to the downstream direction, may be used.

Once the desired pitch has been achieved, the groupings Gl may be transferred to an endless conveyor, for example, travelling at substantially the same velocity Y as the endless track 36. The cam profile is then preferably arranged to cause the elongate members 18 to retract, thus allowing the article groupings G1 at position 46 to progress downstream to the next process, e. g. an article loading station (not shown).

It is naturally of great importance that each elongate member 18 is interposed between the articles"A"at the correct position such that the interposition point coincides substantially with the intersection point between adjacent articles"A". Furthermore, the article infeed, and the elongate member 18 must be synchronised such that the correct number of articles"A"are downstream of the point of interposition, for there to be the correct number of articles"A"in each grouping G 1.

To this end, it is envisaged that the device may be controlled by a suitable controller.

The controller may be a dedicated processor or may be control means for a packaging machine with which the apparatus of the invention is used. Alternatively, the controller may preferably be a known programmable servo control system.

Reference is now made to Figure 6, which illustrates the flow diagram of a suitable controller. The controller has a central processor, a manual input means through which specific instructions can be programmed, and optionally, a display which indicates useful information to the machine operator. The central processor and the display can display operational information such as the speed of operation of the machine and its compliance with particular safety requirements, in the normal manner.

The controller controls the positions of the moveable components as well as the speed of movement of variable speed components. For example, the central processor controls the motors 140 which power the feed means (drive belt, star wheel and device) which move articles to be packed into (the infeed end of) the machine.

Data regarding the infeed rate of articles"A", the dimensions of the articles, the required number of articles"A"in each grouping G I and the spacing of the elongate members 18 is input into the controller. The data may be input manually 70 or may be supplied by one or more sensors (not shown) provided on the infeed stream of the articles 72 and the endless chain 74. Taking this data, the controller 76 computes the relative positions of the articles at the infeed end 42 of the article conveyor means 38, and the elongate members 18. The controller then signals the drive means 78 driving the device to increase or decrease the downstream velocity of lug assemblies 10,1 Oa in order that the correct point of interposition can be achieved. The control means is preferably capable of varying the speed of the elongate members 18 in the range plus or minus 1-30% of the speed of the articles"A"at the infeed end of the article conveying means 38.

If the device is switched regularly between a number of standard groupings and pitches, information regarding the dimensions of articles"A", and the spacing of the elongate

members 18 preferably stored in memory associated with the controller to speed changeover between different configurations.

A different pitch and grouping set up can be seen in Figures 7A and 7B, namely a grouping G2 having a 4 x 3 article configuration with an increased pitch P2 between adjacent article groupings. For this to be achieved, the spacing between the trailing elongate member 18a and a leading elongate member 18b is increased, and the spacing between corresponding leading and trailing elongate members for adjacent groupings G2 is also increased. This is achieved by removing a number of lug assemblies 10,1 Oa and replacing them on alternative mounting members 22. If star wheels are being used to meter the article infeed, these would also need to be adjusted to accommodate the extra row of articles, and the controller reprogrammed to take into account the changes to the drive means 80,82 for the article conveyor and star wheel.

Figures 8A and 8B illustrate a further configuration of elongate members for a 5 x 2 grouping of articles G3 with a pitch P3 therebetween. It can be seen that pitch P3 is substantially identical to pitch PI of Figures 5a and 5b, however the leading elongate member 18b has been moved to accommodate the greater number of articles in the grouping.

Figures 9A and 9B illustrate a further configuration of elongate members for forming a grouping G4 comprising two sets of articles in a 2 x 2 configuration with a space therebetween. The pitch between adjacent groupings P4 is smaller than the pitch of the other configurations. In this embodiment, the differential between the velocity Y of the elongate members, and the velocity Z of the infeed end of the article conveyor means 38 will therefore necessarily be lower than for the other configurations.

It is apparent that, because of the straightforward means for attaching the lug assemblies 10,1 Oa to the mounting members 22, changing the grouping and pitches can be achieved easily and relatively rapidly. To make small adjustments in the elongate member spacings, a combination of lug assemblies 10 and I Oa may be used due to the differing relative positions of the elongate member 18 to the body portion 12.

It will be recognised that as used herein the terms"top","bottom"and"side"with respect to the device are relative terms, and that the device may be re-orientated as necessary or as desired.

The metering device of the present invention may be sold as an integral part of a packaging machine. Alternatively, the device may be sold as an individual module to be fitted to new equipment or existing equipment on a retrofit basis.

Numerous changes may be made within the scope of the present invention, for example for mechanism for deploying the elongate members may be substituted for some form of hydraulic or pneumatic actuators, the design of the lug assemblies may be adjusted for different article types, the securing means for securing the elongate members on the mounting members may be changed as necessary, and a different slide assembly configuration may be used.