EP1427634A1

EP1427634A1 - Dual station applicator wheels for filling cavities with metered amounts of particulate material

Info

Publication number: EP1427634A1
Application number: EP02794885A
Authority: EP
Inventors: Barry S. Smith; Steve Spiers; Jeremy Straight; Janet L. Thompson; Ahmet Ercelebi; Martin T. Garthaffner; Lisa Rogers
Original assignee: Philip Morris Products SA; Philip Morris Products Inc
Current assignee: Philip Morris Products SA
Priority date: 2001-08-17
Filing date: 2002-08-14
Publication date: 2004-06-16
Anticipated expiration: 2022-08-14
Also published as: DE60239688D1; EP1427634A4; ATE504497T1; PL202126B1; BR0212003A; JP2005523680A; BR0212003B1; EP1427634B1; JP4290000B2; PL371207A1; WO2003016137A1

Abstract

Apparatus and method for filling spaced apart cavities (18) with particulate material (24) include a transport (26, 28) for moving the cavities (18) along a path of travel. The cavities (18) are partially filled with particulate material (24) at an upstream location while applying vacuum underneath each cavity (1) during such partial filling. The partially filled cavities (18) are then completely filled with a downstream deposit of particulate material (24) while applying vacuum to the upper sides of each cavity (18) during such filling. The combination of vacuum applied underneath the cavity during partial fill and vacuum applied to the top sides of the cavity (18) during complete fill produces approximately 100 % cavity fill with minimal extraneous scatter of particulate material (24).

Description

DUAL STATION APPLICATOR WHEELS FOR FILLING CAVITIES WITH METERED AMOUNTS OF PARTICULATE MATERIAL

BACKGROUND OF THE INVENTION

The present invention generally relates to methods and apparatus for accurately delivering precisely metered amounts of particulate material from dual station applicator wheels in a repetitive manner during high speed manufacture of particulate-filled articles of manufacture, and more particularly to precise and repetitive delivery of granular carbon from dual station applicator wheels into spaces presented during the manufacture of plug-space-plug cigarette filters.

Certain articles of manufacture such as carbon cigarette filters, individual- sized packets of granular food products or condiments, capsuled pharmaceuticals, ammunition and the like require repetitive placement of precisely metered charges of particulate matter at some location along the production-line procession of the articles. During high speed mass production of such articles it is difficult to achieve consistent accurate filling of the desired cavities with the granular particles. In the case of filling cigarette filter cavities with carbon, it is desirable to avoid excessive pulverization and scattering of the particulate material, while achieving as close to 100% fill of the cavities as possible.

U.S. Patent No. 5,875,824, which is incorporated by reference herein in its entirety, discloses a method and apparatus for delivering predetermined amounts of material, wherein a single metering wheel receives discrete amounts of material from a supply chute, with the discrete amounts of material being transferred from the metering wheel to a transfer wheel, and from the transfer wheel into spaces along a filter rod. As a result of the transfer of particles from one wheel to another, the pockets for receiving the particulate material in the transfer wheel must be larger than the pockets in the metering wheel. This arrangement makes it difficult to achieve 100% fill of the cavities in the article receiving particulate material from the transfer wheel.

According to the '824 patent, granular particles of carbon are drawn from a chute in communication with a reservoir into pockets on a rotating metering wheel. The rim of the metering wheel includes a plurality of equally spaced-apart pockets, each of which is defined by a radially directed, conical bore and a discrete screen at the base of the conical bore. The conical bore is convergent in the radially inward direction. A radially directed channel within the rim of the metering wheel communicates a backside of the screen with the interior of the metering wheel. A vacuum can be communicated from a stationary vacuum plenum in the interior of the metering wheel through the radial channel and screen such that any granular particles of the carbon that are adjacent the pocket in the metering wheel will be drawn into the conical bore of the pocket until it is filled.

SUMMARY OF THE INVENTION

An embodiment of the invention provides a method and apparatus for inserting granular particles of carbon or other materials into cavities defined in an article or plurality of articles, such as a cigarette filter rod, with the cavities being spaced at predetermined intervals. In the case of a cigarette filter rod, the cavities are spaced along the filter rod between filter components. In alternative embodiments the method and apparatus could include inserting particles or granules of other materials such as pharmaceuticals into cavities spaced along an article or in discrete articles such as individual capsules. Filling systems are provided adjacent upstream and downstream rotating applicator wheels each having spaced apart pockets that may be connected to a central stationary vacuum. The rotating wheels include pockets spaced around their outer surfaces, and a perforated metal band or screen which is clamped against the internal circumferential surface of the rotating wheels by a flexible segmented ring. The flexible segmented ring rotates with the wheel and has openings therethrough that coincide with the pockets around the outer surface of each rotating wheel. Each of the pockets is provided with a rectangular shape, extending inwardly until terminating at the perforated band or screen that is clamped against the inner circumference of the rotating wheel.

A stationary or rotatable vacuum plenum is provided in a drum radially inwardly from each rotating wheel and extending along an arc having a length coinciding with the distance between a point at which it is desired to provide vacuum to a pocket to draw in particles and a point at which it is desired to release the vacuum so that the particles can be released from the pocket into cavities traveling adjacent the periphery of the applicator wheels along a longitudinal path of travel.

The filling system adjacent to each rotating wheel includes a vertical drop chute with a height that is determined such that the particles accelerate under gravity through the drop chute and are traveling at approximately the surface speed of the rotating wheels when the particles enter the filling chamber. The filling chamber includes openings at the top to receive the particles from the vertical drop chute, at the bottom so that excess particles can drop out of the bottom of the filling chamber to be captured and recycled, and on the side of the filling chamber facing the rotating wheel. The side of the filling chamber opposite from the rotating wheel is provided with air inlets to allow cross air flow through the filling chamber and into the pockets of the rotating wheel. Each filling chamber can also be provided with optional deflector vanes to assist in deflecting the particles into the wheel pockets. As particles enter the top of the filling chamber from the vertical drop chute, cross air flow produced by the wheel vacuum and the inlets in the side of the filling chamber opposite from the wheel, direct the particles toward the wheel. The vacuum created by the stationary or rotatable internal vacuum plenum pulls the particles into the wheel pockets until the pockets are full. A scraper can be provided at the bottom of the filling chamber to scrap the outer surface of the wheel, thereby ensuring that each wheel pocket is accurately filled. A stationary air jet can also be provided inside the stationary vacuum plenum at a position adjacent the end of the vacuum plenum in the direction of rotation of the rotating wheel. The air jet directs a blast of air radially outwardly to assist in rapidly emptying each pocket of the rotating wheel as it rotates past the end of the vacuum plenum.

The cavities to be filled with the granules or particles are passed underneath each rotating applicator wheel and their movement is synchronized with the movement of the rotating wheels so that each cavity to be filled coincides with a pocket on the outer surface of each rotating wheel. A vacuum rail for conveying the article or articles having the cavities to be filled can also be provided. The material in which the cavities are formed can be porous material that allows the vacuum from the vacuum rail to create a negative pressure in the cavities. An example of such a porous material is the paper plug wrap used in forming cigarette filter rods. The vacuum rail can also be provided with separate chambers having higher and lower amounts of vacuum such that a chamber having the higher vacuum coincides with the cavity that is being filled with particles from the rotating wheel, while the other areas of the article coincide with the chambers having lower vacuum. The use of a high vacuum section in the vacuum rail at the point of particle transfer, and low vacuum at other points allows for quicker transfer of particles at the transfer point without having to adjust the rate at which the cavities are moved underneath the rotating wheel.

Both the upstream and downstream applicator wheels meter the particles and transfer the particles to cavities traveling underneath the wheels. The upstream wheel initially deposits a portion of the granular material into each cavity, and at the point of transfer from the upstream applicator wheel to the cavities, relatively high vacuum is applied to the cavities from below to draw in and affect transfer of the particulate material. The remaining portion of particulate material necessary for 100% cavity fill is transferred from the downstream applicator wheel to the partially filled cavities. At the location of the downstream applicator metering wheel relatively high vacuum is also applied at the point of transfer of the particulate material into the partially filled cavities, but such vacuum is applied at the upper sides of the cavity. Application of vacuum in this manner is instrumental in achieving approximately 100% fill of each cavity.

BRIEF DESCRIPTION OF THE DRAWINGS

Novel features and advantages of the present invention in addition to those mentioned above will become apparent to persons of ordinary skill in the art from a reading of the following detailed description in conjunction with the accompanying drawings wherein similar reference characters refer to similar parts and in which:

Figure 1 is a diagrammatic side elevational view of a high speed apparatus that includes dual station applicator wheels for filling cavities with metered amounts of particulate material;

Figure 2 is a sectional view taken along line 2-2 of Figure 1 ;

Figure 3 is a fragmental perspective view illustrating partially and completely filled cavities; Figure 4 is a sectional view taken along line 4-4 of Figure 1 ;

Figure 5 is a sectional view taken along line 5-5 of Figure 1 ;

Figure 6 is a sectional view taken along line 6-6 of Figure 1 ;

Figure 7 is a sectional view taken along line 7-7 of Figure 1 ;

Figure 8 is a sectional view taken along line 8-8 of Figure 1 ;

Figure 9 is a sectional view taken along line 9-9 of Figure 1 ;

Figure 10 is a sectional view illustrating an alternate embodiment of the present invention wherein the upstream and downstream filling stations each include a pair of side-by-side applicator wheels;

Figure 11 illustrates a system for producing cigarette filter rods having two particle insertion points; and

Figure 12 illustrates a single particle inserter including a vertical drop chute, a filling chamber, a rotating wheel around a stationary vacuum manifold, and a vacuum rail for transporting an article with cavities to be filled.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a system useful for transferring accurately metered volumes of particles to cavities in an article or articles being produced at a high rate during mass production of the articles. The system includes upstream and downstream applicator wheels each of which rotates around a central stationary drum or vacuum plenum defining at least one vacuum chamber. A series of pockets are defined along an outer circumferential surface of each rotating applicator wheel between the outer periphery of the wheel and a perforated band or screen that is clamped against the inner periphery of the wheel, to both accurately meter and transfer predetermined amounts of granules or particles into cavities of one or more articles. Accurate metering and transfer of particles is achieved through the use of dual filling stations each of which includes a filling system that uses gravitational acceleration of the particles and cross air flow to achieve rapid filling of the pockets in each rotating applicator wheel, and a vacuum rail for transporting the article or articles that is used in conjunction with an air jet located inside each rotating wheel to ensure rapid emptying of the pockets in the rotating wheel and accurate filling of the cavities in the article moved along the vacuum rail.

The drawings illustrate an assembly line for producing cigarette filter rods of spaced apart cellulose acetate plugs with cavities therebetween filled with particulate material and surrounded by plug wrap. Initially the paper wrapped around the filter rod is left open at the top side of the filter rod as the filter rod passes by dual filling stations. Particles and granules of carbon are inserted into the spaced cavities along the filter rod through the openings on the top side of the filter rod as the rod passes under the filling stations. A first upstream filling station can be used for partially fill or completely fill a cavity, and then a second downstream filling station can top off the partially filled cavity or a filled cavity that has been compacted, or in which the particles have settled between the first and second filling station. At the upstream applicator wheel vacuum is applied to the plug wrap from below the cavity being filled, and at the downstream applicator wheel vacuum is applied to the top sides of the plug wrap to completely fill the partially filled cavity. This particular combination of vacuum application ensures 100% cavity fill. After the rod leaves the filling stations and continues to travel downstream, the paper plug wrap that has been left open at the top of the filter rod is folded over the filter components and particle filled cavities and glued and sealed to complete the filter rod construction.

Referring in more particularity to the drawings, Figure 1 illustrates a diagrammatic side elevational view of high speed machinery 10 that includes dual station applicator wheels for filling cavities with metered amounts of particulate material in the manufacture of cigarette filter rods. Fundamentally, at the entrance to machinery 10 spaced apart plugs 12 of cellulose acetate are secured to plug wrap paper 14 by glue deposited onto paper 14 at glue applicator 16. A Molins double action plug tube combiner, well known in the industry, may be used to establish a procession of plugs in registered spaced apart relationship onto the plug wrap paper 14. The paper 14 is partially wrapped around the spaced apart plugs 12 but left open at the top side to thereby form spaces or cavities 18 between adjacent plugs traveling along a longitudinal path through the machinery 10. Upstream and downstream applicator wheels 20, 22 function to supply discrete portions of particulate material such as carbon 24 into the cavities 18, as explained more fully below. After the cavities are filled with the particulate material, the paper 14 is folded and glued in place around the cellulose acetate plugs and the filled cavities therebetween.

Upstream and downstream belts, 26 and 28 respectively, function to draw the plug wrap 14 with the spaced apart cellulose acetate plugs 12 secured thereto along a longitudinal path of travel through the machinery 10. A perforated vacuum rail 29 between the belts 26, 28 maintains the plug wrap and filter components in place along a longitudinal path of travel. Initially, as shown in cross section in Figure 2, the plug wrap 14 is folded into a U-shaped configuration as the paper and plugs travel through a garniture 30. The paper continues to be folded into the configurations shown in Figures 4 and 5.

A portion of the particulate material 24 is deposited into each of the cavities 18 as they travel past the upstream applicator wheel 20. The applicator wheel 20 forms part of the first filling station and the wheel includes pockets 34 that receive carbon material 24 from a carbon chute 36. The carbon chute is supplied with carbon from a hopper 38. Vacuum is applied to the inner bottom surface of each pocket on the applicator wheel as the pockets travel past the carbon chute 36, and the carbon is thereby drawn into each of the pockets 34. Ultimately, when the pockets 34 filled with carbon 24 reach registration with the cavities 18, pressure is applied to urge the carbon out of pocket into the cavity.

As the cellulose acetate plugs 12 and plug wrap 14 approach the upstream applicator wheel 20 low vacuum 40 is applied to the underside of the plug wrap through the perforated vacuum rail 29 from a low vacuum plenum 41. Moreover, at the point of transfer of carbon 24 from the pockets of the first applicator wheel 20 into the cavities 18, high vacuum 42 is applied to the underside of the cavity from below the plug wrap. The application of pressure urging the carbon 24 out of pockets 34 on the applicator wheel in combination with the application of high vacuum below the cavities 18 functions to effectively transfer the carbon from the pockets of the applicator wheel into the cavities. Basically, the first applicator wheel 20 is constructed and arranged to partially fill each cavity 18 with carbon sufficient to fill the cavity approximately 30 to 60%, usually about 50%. Such partial fill is shown best in Figure 6.

The filter rod assembly comprising the spaced apart cellulose acetate plugs 12 secured to the plug wrap 14 together with the partially filled cavities 18 travels in a downstream direction being pulled downstream by the downstream garniture belt 28. Low vacuum 40 is applied to the underside of this assembly as it travels from the first upstream applicator wheel 20 to the second downstream applicator wheel 22 where the remainder of each cavity is filled with carbon 24. The second applicator wheel 22 forms part of the second filling station and is similar in construction to applicator wheel 20. When the partially filled cavities are in registration with the pockets 34 of the second applicator wheel, the remaining carbon necessary to completely fill the cavity is transferred from the pockets to the cavities by pressure applied to the underside of each pocket at its transfer location and also by high vacuum applied to the cavity. However, as shown best in Figure 7, the application of high vacuum is directed to the top side of the cavity on the outside of the plug wrap and such application functions to hold the carbon within the cavity for approximately 100% cavity fill.

The application of high vacuum to the underside of the cavity during carbon transfer at the first filling station in combination with the application of high vacuum to the top side of the cavity during the transfer of carbon at the second filling station ultimately produces a fully filled cavity with minimal scatter of the carbon onto the adjacent cellulose acetate plugs 12. The release of carbon 24 by both applicator wheels 20, 22 begins at the hour hand position of 4:30. This is where air is applied to the pocket and the transfer of carbon begins. Transfer is completed at the 6:00 position.

Upon moving past the second downstream applicator wheel 22 the plug wrap filter paper 14 is folded around the filled cavities 18 and cellulose acetate plugs 12 in a pre-exit folder 48, as shown in Figure 8. Ultimately, the filled cavities and cellulose acetate plugs pass through an exit folder 50 where the paper 14 is almost completely folded around the plugs and filled cavities except for an upstanding glue flap portion of the plug wrap. Glue is applied to the flap at station 52 and the flap is folded down to thereby produce a cylindrical filter rod comprising spaced apart plugs 12 and carbon filled cavities 18 with plug wrap 14 wrapped around the plugs and cavities and glued in place. Front and rear vacuum folders 50 cause air flow to occur down through folders 50 by drawing air through the plug wrap. This downstream air flow maintains the 100% fill in cavities 18.

Figure 10 shows an alterative embodiment 10A where each filling station includes side by side applicator wheels to thereby accommodate parallel paths of travel for simultaneous manufacture of two filter rods. In the embodiment of Figure 10 duplicate lines are formed, but otherwise each path of travel is the same as described above.

Machinery 10, 10A also includes a first upstream sensor 60 at a location just upstream of the first applicator wheel 20 for adjusting the phase of the wheel with respect to the appearances of the cavities 18 at the sensor location. A second sensor 62 is positioned just upstream of the downstream applicator wheel 22 to likewise adjust the phase of the second applicator wheel to precisely correspond with the phase of the arrival of the cavities 18 between the cellulose acetate plugs 12 approaching the nip of the second applicator wheel.

As described above, the present invention utilizes two or more applicator metering wheels such that the upstream metering wheel 20 effects partial filling of the cavities while the downstream applicator wheel 22 completes the filling operation so as to maximize the percent fill of the cavities on a constant basis. This arrangement enhances machine speed operation and also provides the capacity to include different adsorbents in the same cavity of plug-space-plug filter constructions. In this regard, the pockets 34 of the first upstream applicator wheel 20 may be charged with one adsorbent while the pockets of the downstream applicator wheel 22 may be charged with a totally different adsorbent to thereby produce an adsorbent combination in each cavity. The present invention provides arrangements of how much and from where vacuum is drawn at and about the upstream and downstream applicator wheels to thereby completely fill the cavities between the cellulose acetate plugs while avoiding ricochet and/or escape of the adsorbent particles being charged into the cavities.

In the region of the entrance pathway adjacent both the upstream and downstream applicator wheels low vacuum of about 30 millibars is drawn from beneath the plug wrap 14 except at the nip of the applicator wheels where a relatively high vacuum of about 70 millibars is drawn from beneath the plug wrap to ensure a complete and quick transfer of the carbon from the pockets of the applicator wheels into the cavities 18.

Just upstream of the nip of the second downstream metering wheel 22, the partially filled pockets and plugs enter a garniture section that is configured to draw elevated vacuum from along the sides of the folded-open plug wrap. As explained above, vacuum is not drawn from beneath the plug wrap. The elevated drawing of vacuum along the sides promotes a speedy and clean transfer of carbon from the pockets 34 of second metering wheel 22 to the partially filled cavities 18, and promotes retention while minimizing scatter of the particulate 24. Soon after passing through the nip, the procession of plugs enters a top folder garniture portion, wherein a lesser (~ 30 millibars) vacuum is drawn in the same manner along the sides instead of from below.

Accordingly, in the present invention a high vacuum is drawn adjacent only the delivery point of each wheel and such vacuum is drawn from beneath the first wheel 20 but only along the sides of the plug wrap 14 at the second wheel 22. This is a profound change and found effective for controlling scatter while achieving high machine speeds and 100% cavity fill. Machinery 10, 10A also includes a master drive system (not shown) that operates the following: the drive units of the plug hoppers and the first garniture belt 26; the motor of the spacer drum; the drive units of the upstream and downstream applicator metering wheels 20; 22; the second garniture belt 28; and a cutter head for severing the continuous filter rod into desired lengths.

Aspects include adjusting the speed of the second belt 28 to achieve desired rod output of the system and determining speeds of all other units relative to that desired, second belt speed. Furthermore, the first belt 26 is driven slightly less than (~ 0.07%) or equal to the speed of the second tube belt 28 so as to avoid bunching of the rod under construction. A cutter head (not shown) is adjustable in phase to maintain registration of the cut respective to internal plug structure. Sensors 60, 62 adjacent the metering wheels allow for adjustment of the phase of each metering wheel relative to the phase of passing plugs, as explained above.

The invention provides a system useful for transferring accurately metered volumes of particles to cavities in an article or articles being produced at a high rate during mass production. The system includes a single wheel that rotates around a central stationary drum defining at least one vacuum chamber. A series of pockets are defined along an outer circumferential surface of the rotating wheel between the outer periphery of the wheel and a perforated band or screen that is clamped against the inner periphery of the wheel, to both accurately meter and transfer predetermined amounts of granules or particles into cavities of one or more articles. Accurate metering and transfer of particles is achieved through the use of a combination ^' of features that include a filling system that uses gravitational acceleration of the particles and cross air flow to achieve rapid filling of the pockets in the rotating vacuum wheel, and a vacuum rail for transporting the article or articles that is used in conjunction with an air jet located inside the rotating wheel to ensure rapid emptying of the pockets in the rotating wheel and accurate filling of the cavities in the article moved by the vacuum rail.

Another embodiment according to the invention is shown in Figure 11 which illustrates an assembly line for producing cigarette filter rods. A hopper section delivers a filter rod with a filter component - empty cavity - filter component to a downstream section where two filling stations are shown. The paper wrapped around the filter rod is left open at the top side of the filter rod as the filter rod passes by the filling stations. Particles or granules of carbon are inserted into the spaced cavities along the filter rod through the openings on the top side of the filter rod as the rod passes under the insertion stations. A first insertion station can be used to partially fill or completely fill a cavity, and then the second insertion station can top off the partially filled cavity or a filled cavity that has been compacted, or in which the particles have settled between the first and second insertion stations. After the rod leaves the insertion stations and continues to travel to the left in Figure 11 , a cleaning system removes scattered particles from the surface of the filter components spaced in between the particle filled cavities. After the filter rod leaves the cleaning section, the paper that has been left open at the top of the filter rod is folded over the filter components and particle filled cavities and glued and sealed to complete the filter rod. This layout is familiar to those of ordinary skill in the pertinent art, such as a GC apparatus from Hauni-Korber AG of Hamburg, Germany. This is described in ^'US 5,875,824 which is incorporated by reference in its entirety for all usefull purposes.

In a further embodiment of the invention illustrated in Figure 12, a vacuum wheel 200 includes an outer rotating wheel 204 and a stationary central drum 100 defining at least one stationary vacuum plenum 110. A vacuum is maintained in vacuum plenum 110 through vacuum ports 120, 122. A stationary air jet 130 can also be provided in the central stationary drum 100, adjacent one end of the vacuum plenum in the direction of rotation of the rotating wheel 204. The vacuum plenum 110 extends along an arc for a length corresponding to the distance between a point A where particles are provided to a pocket 210 in the outer rotating wheel 204, and a point B where the vacuum holding particles in the pocket 210 is released so that the particles can be filled into a cavity 7 in an article 305 that is being transported underneath the rotating wheel 204 by a vacuum rail 405.

A filling system is provided adjacent the outer circumferential surface of rotating wheel 204 in order to direct granular particles into the pockets 210 of rotating wheel 204. The filling system includes a vertical drop chute 400 and a filling chamber 300. Granules or particles 410 fall through the vertical drop chute between guide vanes 402. The vertical drop chute preferably has a length such that particles entering the filling chamber 300 from the vertical drop chute 400 are traveling at a speed approximately the same as the surface speed of rotating wheel 204. This feature increases the likelihood of a complete filling of the pockets 210 without undesirable pulverization of the particles.

Rotating wheel 204 includes spaced-apart pockets 210 that are generally rectangular in shape and milled inwardly from an outer circumferential surface of rotating wheel 204 to an inner circumferential surface terminating at a perforated band or screen 214. The perforated band or screen 214 is clamped against the inner circumferential surface of rotating wheel 204 by a flexible segmented clamp ring 220. The segmented clamp ring 220 is provided with spaced openings 222 that coincide with the pockets 210 in the outer rotating wheel 204.

When a pocket 210 in outer rotating wheel 204 reaches position A, as show in Figure 12, a vacuum is created in the pocket as a result of the connection between the central stationary vacuum plenum 110 and the pocket through an opening 222 in segmented clamp ring 220 and through the perforated band or screen 214. The vacuum is maintained in the pocket 210 as the rotating wheel 204 continues to rotate until the pocket is in line with position B, as shown in Figure 12. As a pocket 210 rotates past the position B in a clockwise direction, as shown in Figure 12, the pocket is no longer connected to the vacuum plenum 110 through a corresponding opening 222 in segmented clamp ring 220. In order to assist in the rapid emptying of particles from the pocket 210, in addition to releasing the vacuum supplied to the pocket as a result of the pocket passing the end of stationary central vacuum plenum 110, an air jet 130 can also be provided in the central stationary drum 100 as shown in Figure 12. Clockwise rotation of outer wheel 204 moves a pocket 210 from radial alignment with central vacuum plenum 110 to radial alignment with the air jet 130. The air jet 130 provides a blast of air through an opening 222 in segmented clamp ring 220, and through the perforated band 214 to assist in emptying particles from the pocket 210.

Granules or particles 410 dropping from the vertical drop chute 400 into filling chamber 300 can be deflected toward the pockets 210 in rotating wheel 204 by deflector guide vanes 340. The vacuum that is pulled through the pockets 210 positioned along the side 304 of filling chamber 300 also results in a cross air flow through the filling chamber 300 as air is sucked in through inlets 320 on the opposite side 308 of filling chamber 300. The cross air flow through filling chamber 300 and deflector vanes 340 assists filling of each pocket 210 with the granules or particles 410 as wheel 204 rotates clockwise in Figure 12. A scraper 360 can also be provided near the bottom 306 of filling chamber 300 and in contact with the outer circumferential surface 202 of rotating wheel 204. The scraper 360 removes excess particles from the outer circumferential surface 202 of rotating wheel 204, to thereby provide a desired amount of particles in each of the pockets 210. The excess particles drop from the bottom 306 of filling chamber 300, and can be recycled.

As each pocket 210 rotates clockwise past the bottom of the filling chamber 300, the granules or particles 410 are retained within the pocket as a result of the vacuum from vacuum plenum 110 until the pocket 210 reaches position B, as shown in Figure 12. As a pocket 210 continues past position B in a clockwise direction, the vacuum from central vacuum plenum 110 is no longer communicated through segmented clamp ring 220 to the pocket, and the air jet 130 provides a burst of air to empty the particles from the pocket 210.

A cavity 70 in article 305 passes underneath the rotating wheel 204 in synchronization with the pockets 210 such that the cavity 70 is aligned with a pocket 210 when the particles are emptied from the pocket by air jet 130. If the cavity 70 is defined by a porous material such as the paper in a cigarette filter rod, a vacuum can be applied at this point below the cavity 70 in order to assist in filling the cavity with particles from the pocket 210. The vacuum rail 405 provided below the article 305 having cavities 70 can include one or more chambers having relatively higher vacuum 440 and use one or more chambers having relatively lower vacuum 420. The high vacuum chamber 440 can be positioned to align with the pocket 210 that is being emptied of particles 410. Auxiliary air flow around the article 305 can also be provided by lower vacuum chambers along vacuum rail 405 in order to ensure that any excess particles are cleaned from the surface of the article 305. The communication of vacuum from vacuum chamber 440 to the cavity 70 passing beneath the air jet 130 contributes to a positive withdrawal of granules or particles 410 from the pocket 210 of wheel 204 into the cavity 70. The vacuum positively retains the granules or particles in the cavity 70 as well as clearing any loose particles from the external surfaces of the article 305.

In the case of filling cavities in a cigarette filter rod with granules or particles such as carbon, the filter rod can be completed after filling each cavity 70 with particles by the application of an adhesive along edge portions of the filter wrap defining the cavities 70. The filter wrap is then sealed as the filter rod continues downstream from the point at which each cavity is filled.

One skilled in the art will appreciate that the present invention may be practiced by embodiments other than the above-described embodiments, which have been presented for purposes of illustration and not of limitation. The device and methodologies embodied in the above-described embodiments are adaptable to delivering various types of particulate or granular material and could be used in applications other than the filling of portions of cigarette filters. For example, the device is readily adaptable to the filling of pharmaceutical doses, or the repetitive displacement of powdered food stuffs or other powdered, granular or particulate products into discrete packaging or containers.

Claims

WHAT IS CLAIMED IS:

1. Apparatus for filling spaced apart cavities with particulate material comprising: a transport for moving the cavities along a path of travel; a first filling station for partially filling the cavities including an upstream applicator wheel with spaced apart pockets on the periphery thereof; a first supply of particulate material adjacent the upstream applicator wheel for depositing the material into the pockets; first transfer means for transferring the particulate material from the pockets to partially fill the cavities including the application of vacuum underneath the cavity being partially filled at a point of transfer of the particulate material from the pockets into the cavities; a second filling station for completely filling the partially filled cavities including a downstream applicator wheel with spaced apart pockets on the periphery thereof; a second supply of particulate material adjacent the downstream applicator wheel for depositing the material from the second supply into the pockets; and second transfer means for transferring the particulate material from the pockets of the downstream applicator wheel into the cavities including the application of vacuum to the upper sides of the cavity being filled at a point of transfer of the particulate material from the pockets of the downstream applicator wheel into the cavities.

2. An apparatus as in claim 1 , wherein the particulate material in the first supply and the second supply is the same. ^'3. ^'An apparatus as in claim 1 , wherein the first and second transfer means includes the application of relatively lower vacuum to the underside of the cavities immediately upstream of the points of transfer.

4. A method for filling spaced apart cavities with particulate material comprising the steps of: transporting spaced apart cavities along a path of travel; partially filling each cavity with particulate material while applying vacuum underneath each cavity during such filling; and completely filling each cavity with particulate material while applying vacuum to the upper sides of the cavity during such filling;

5. A method as in claim 4, wherein the cavities are partially and then completely filled with the same particulate material.

6. A method as in claim 4, wherein the cavities are partially filled with one particulate material and then completely filled with a different particulate material.

7. A method as in claim 4, further including the steps of: applying vacuum underneath the cavities immediately upstream of the partial filling step and the complete filling step.

8. Apparatus for filling at least one cavity in an article with granular or particulate material, the apparatus comprising: a filling chamber containing the material; a rotating wheel having at least one pocket defined in an outer circumferential surface, the at least one pocket receiving the material in the filling chamber and the outer circumferential surface defining at least part of a side of the filling chamber; and a conveying device adapted to position at least one article having at least one cavity to be filled with the material underneath the wheel to receive the material from the at least one pocket.

9. An apparatus as in claim 8, further including a stationary drum positioned inside of the rotating wheel and defining a vacuum chamber in communication with the at least one pocket over a predetermined distance of rotation of the rotating wheel.

10. An apparatus as in claim 8, wherein the at least one pocket comprises a plurality of rectangular pockets defined in the outer circumferential surface of the rotating wheel, with a radially inner extent of the pockets being defined by a single perforated band or screen positioned against the inner circumferential surface of the wheel.

11. An apparatus as in claim 8, further comprising a chute supplying the material to the filling chamber.

12. An apparatus as in claim 10, wherein the perforated band or screen is clamped against the inner circumferential surface of the wheel by a clamp ring positioned inside the wheel.

13. An apparatus as in claim 11 , wherein the chute has a length such that the material entering the filling chamber from the chute is traveling at a velocity approximately equal to the velocity of the pockets on the outer circumferential surface of the wheel.

14. An apparatus as in claim 13, wherein guide vanes are provided within the filling chamber for directing the material toward the pockets in the wheel.

15. ^' An apparatus as in claim 8, wherein the conveying device includes at least one vacuum chamber for drawing the material into the at least one cavity from the wheel.

16. An apparatus as in claim 15, wherein the conveying device includes at least one chamber having relatively higher vacuum and at least one chamber having relatively lower vacuum, with the at least one higher vacuum chamber being positioned underneath a cavity being filled with material from a pocket in the wheel.

17. A method of filling a cavity in an article with granular material, the method comprising: providing a wheel rotatable around a stationary drum defining a vacuum chamber, the wheel having at least one pocket defined in its outer periphery, and at least a portion of the outer periphery of the wheel defining at least a portion of one side of a filling chamber; rotating the wheel around the stationary drum and creating a vacuum in the vacuum chamber; dropping the material into the filling chamber; and communicating the vacuum to the at least one pocket over a distance from when the at least one pocket is positioned along the one side of the filling chamber and interrupting the vacuum at a point at which material in the at least one pocket is transferred to a cavity in an article.

18. The method as in claim 17, further including: blowing air through the at least one pocket when the at least one pocket is positioned over a cavity in an article to assist in emptying the pocket into the cavity.

19. ^" An apparatus for filling at least one cavity in an article with granular or particulate material, the apparatus comprising: a filling chamber into which the granular or particulate material is dropped through a top opening; a stationary vacuum chamber; and a plurality of spaced apart receptacles wherein each of the receptacles is mounted for movement past the stationary vacuum chamber and into alignment with a corresponding cavity in an article, the receptacles being in communication with a vacuum created in the stationary vacuum chamber from a first point at which the granules or particles are introduced into the receptacles from the filling chamber to a second point near where the granules or particles are inserted into the corresponding cavities.

20. An apparatus as in claim 19, wherein the plurality of spaced apart receptacles are formed in the outer periphery of a wheel that rotates around the stationary vacuum chamber.

21. An apparatus as in claim 20, wherein a vacuum rail is provided for supporting and moving an article having cavities to be filled with granules or particles underneath the wheel.

22. An apparatus as in claim 21 , wherein the vacuum rail includes a vacuum that pulls granules or particles from the receptacles into the cavities and cleans away loose granules or particles positioned on the article outside of the cavities.

23. An apparatus as in claim 22, further including a drop chute positioned above the filling chamber and through which granules or particles are dropped to accelerate under the influence of gravity before entering the filling chamber.

24. ^' An apparatus as in claim 23, wherein the filling chamber includes a plurality of openings on a side opposite from the side of the filling chamber where granules or particles are introduced into the receptacles.

25. An apparatus as in claim 24, wherein an air jet is provided adjacent the stationary vacuum chamber and the second point for blowing the granules or particles into the corresponding cavities.

26. An apparatus as in claim 25, wherein a single perforated band or screen defines the bottoms of a plurality of the spaced apart receptacles.

27. An apparatus as in claim 26, wherein a segmented clamp holds the perforated band or screen against the inner periphery of the wheel.

28. A system for filling at least one cavity in an article with granular or particulate material, the system comprising: at least one insertion station, the insertion station including a filling chamber into which the granular or particulate material is dropped through a top opening; a stationary vacuum chamber; and a plurality of spaced apart receptacles wherein each of the receptacles is mounted for movement past the stationary vacuum chamber and into alignment with a corresponding cavity in an article, the receptacles being in communication with a vacuum created in the stationary vacuum chamber from a first point at which the granules or particles are introduced into the receptacles from the filling chamber to a second point near where the granules or particles are inserted into the corresponding cavities.

29. A system as in claim 28, wherein two of the insertion stations are provided with a first one of the two insertion stations at least partially filling a cavity in an article with particles, and a second one of the two insertion stations adding more of the particles or a different material to the same or a different cavity in the article.