WO1999040805A2 - Cigarette making machine - Google Patents

Abstract

A hopper (10) for a cigarette making machine comprises two receptacles (12, 14) for receiving tobacco from a primary source. The receptacles (12, 14) are selectively communicable with a feed mechanism of the machine. The arrangement is such that each receptacle can discharge tobacco housed therein to the feed mechanism via a chute (44) whilst the other receptacle receives tobacco from the primary source and is prevented from discharging to the feed mechanism. By arranging the receptacles (12, 14) side-by-side the height of the hopper can be reduced.

Description

1 Cigarette Making Machine

2 The invention relates to apparatus for delivering tobacco to

3 the cigarette rod forming portion of a cigarette making machine A and is particularly, but not exclusively, concerned with a hopper

5 for such a machine.

6 In many cigarette making machines, a filler stream of

7 tobacco is formed on the underneath surface of a suction band, the β tobacco being fed towards the suction band along an upwardly 9 extending passage with the aid of an upwardly flowing airstream. lo The filler stream carried by the suction band is trimmed by a π trimmer and is then deposited on a continuous wrapper web in which i2 the tobacco is enclosed to form a cigarette rod. Examples of such i3 machines are the Molins Mark 8, Mark 9 and Passim cigarette making i4 machines. is It is usual for the tobacco which forms the filler stream to i6 be fed into a hopper from a primary source and subsequently i7 through a winnowing device prior to being fed to the suction band, is It is known to provide a hopper for a cigarette machine i9 which hopper comprises two receptacles disposed one above the

20 other. The upper receptacle receives tobacco from the primary

2i supply and feeds it to the lower receptacle from whence the

22 tobacco passes to a feed mechanism by which it is fed to the

23 suction band via a winnowing device. A trap-door is provided

24 between the upper and lower receptacles to allow the upper

25 receptacle to be filled whilst the lower receptacle delivers

26 tobacco to the feed mechanism. In use, the trap-door is opened at

27 appropriate times to replenish the store of tobacco in the lower

28 receptacle. An example of such a hopper can be seen on the Molins

29 Passim cigarette making machine. This arrangement has proved to

30 work well but has the disadvantage that the overall height of the 3i hopper is significant and can be a problem.

32 The invention provides a hopper for a cigarette making

33 machine, said hopper comprising at least two receptacles for

34 receiving tobacco from a primary source and said receptacles each

35 being selectively communicable with a feed mechanism of said

36 machine such that each can discharge the tobacco housed therein

3 for delivery to said feed mechanism while the other or at least

38 one of the other said receptacles receives tobacco from said 1 primary source. It will be appreciated that in such an arrangement

2 the receptacles can be arranged side-by- side thereby providing the

3 possibility of reducing the height of the machine. In basic

4 embodiments, the invention provides a cigarette making machine

5 comprising two receptacles disposed side-by-side for receiving β tobacco from a primary source, the arrangement being such that 7 whilst one said receptacle receives and stores tobacco from said β primary source, the other said receptacle discharges tobacco 9 stored therein to a feed mechanism of the machine. ιo A problem which can occur in known cigarette making machines a is the blockage of various passages through which the tobacco i2 passes en route to the suction band. This is known as choking and i3 typically the clearance of choke tobacco has involved stopping the i4 cigarette machine, manually removing the choke tobacco from the is machine and transporting it back to the hopper. i6 According to another aspect of the invention there is i7 provided a cigarette making machine comprising a hopper for is receiving tobacco from a primary source, an upwardly extending i9 passage for conducting tobacco to a cigarette rod making portion

20 of the machine and means for conducting tobacco from said hopper

2i to said passage, the arrangement being such that choke tobacco in

22 said passage and/or said conducting means can be returned to said

23 hopper at least in part by means of a pneumatic force.

24 The invention also includes apparatus for use in

25 manufacturing cigarettes, the apparatus comprising a reservoir for

26 receiving tobacco from a primary source, means for forming a

27 cigarette rod, means for conducting tobacco from said reservoir to

28 said rod forming means and return duct means for returning choke

29 tobacco from said conducting means to said reservoir, said

30 conducting means being defined by at least one wall which is 3i movable to open a respective portion of said conducting means to

32 permit access to choke tobacco in said portion and the arrangement

33 being such that said choke tobacco can be conveyed to said

34 reservoir via said conducting means and said return duct means.

35 The invention also includes a cigarette making machine

36 comprising a hopper for receiving tobacco from a primary source,

37 an upwardly extending passage for conducting tobacco to a

38 cigarette rod making portion of the machine and means for 1 conducting tobacco from said hopper to said passage, said passage

2 being defined by a plurality of walls at least one of which is

3 movable outwardly of the passage to allow choke tobacco in the

4 passage to fall to a collection space from which such choke

5 tobacco is returnable to said hopper by pneumatic or other

6 conveyance means.

7 In order that the invention may be well understood, some

8 embodiments thereof, which are given by way of example only, will

9 now be described with reference to the drawings, in which: ιo Figure 1 is a schematic representation of a hopper according ii to the invention; i2 Figure 2 is a schematic representation of apparatus for i3 delivering tobacco to the cigarette rod forming portion of a i4 cigarette making machine including the hopper shown in Figure 1; is Figure 3 is a schematic view of a valve in a primary feed to i6 the hopper; i7 Figure 4 is a schematic sectional view of another hopper is according to the invention in a first operating position; i9 Figure 5 is a view corresponding to Figure 4 showing the hopper

20 in a second operating position;

2i Figure 6 is a sectional view of the hopper taken along line

22 VI-VI in Figure 4;

23 Figure 7 is a schematic representation of apparatus for

24 delivering tobacco to the cigarette rod forming portion of a

25 cigarette making machine which includes the hopper shown in

26 Figures 4 to 6;

2 Figure 8 is an enlarged view of a portion of Figure 7

28 showing the apparatus downstream of the hopper;

29 Figure 9 shows a portion of the apparatus shown in Figure 7 when

30 in a choke clearing mode;

3i Figure 10 shows the apparatus in an alternative choke

32 clearing mode; and

33 Figure 11 is a cross-sectional view of a diverter valve

34 which could be used with the apparatus shown in Figure 2 or Figure

35 7.

36 A first hopper 10 according to the invention is shown in

37 Figures 1 to 3. In the description of the hopper which follows,

38 reference will be made to parts of a cigarette making machine 1 downstream of the hopper; for example, a feed mechanism and a

2 winnowing device. These features are illustrated and described

3 only generally in connection with the hopper 10. For a detailed

4 description of a feed mechanism and winnowing device for use with

5 the hopper 10, attention is directed to Figures 7 to 10 and the

6 description which follows relating to those drawings.

7 Referring to Figures 1 to 3, a first hopper 10 according to

8 the invention comprises a box-like structure divided into three

9 compartments, or receptacles 12, 14, 16 which extend downwardly ιo from a roof portion 18 of the hopper. The receptacles are defined li by the outer walls of the hopper and two dividing walls 20, 22 i2 which are disposed internally of the hopper and extend over i3 approximately 75 per cent of the height of the hopper. i4 The receptacles 12, 14 are supplied with tobacco from a is primary source indicated by box 24 in Figure 2. The tobacco is i6 sucked into the hopper via a feed pipe 26 under the influence of a i7 suction fan indicated by box 28. The feed pipe 26 branches to is respective inlet openings 30, 32 defined in the outer wall of the i9 hopper. The inlet opening 30 leads to the receptacle 12 and the

20 inlet opening 32 leads to the receptacle 14. The fan 28 is

2i connected to the hopper by means of a suction pipe 33 which

22 branches from respective air outlets 34, 36 provided above the

23 inlet openings. The outlet 34 is associated with the receptacle 12

24 and the outlet 36 is associated with the receptacle 14. A screen

25 38 extends across the receptacles 12, 14 just above the inlet

26 openings 30, 32. The mesh of the screen is such that the tobacco

27 sucked into the hopper cannot pass to the outlets 34, 36. A

28 butterfly valve 44 is provided in each outlet.

29 At the lower end of the receptacles 12, 14 a chute 45 is

30 defined by opposed inclined walls 46, 48. The chute is arranged to 3i direct tobacco released from the receptacles to a feed mechanism

32 which is indicated generally at 50 in Figure 2.

33 A valving arrangement in the form of a gate member 58 is

3 disposed in the chute 45. The gate member is shown in an

35 intermediate position in Figure 1 with one of its closed positions

36 being indicated by means of ghost lines. The gate member 58 is

37 pivotally mounted at its lower end (indicated at 60) and extends

38 over the full length (in the direction normal to the plane of the 1 drawing) of the hopper 10. In the closed position indicated in

2 Figure 1, an accurate upper surface 61 of the gate member 58

3 defines a floor for the receptacle 12 allowing the receptacle to

4 be filled with tobacco. The gate member can be pivoted clockwise

5 from that closed position to a second closed position in which it e defines the floor of the receptacle 14 and leaves the receptacle 7 12 open to permit the flow of tobacco housed therein into the β chute 45.

9 The compartment 16 is arranged to receive surplus tobacco ιo ('ecretage') from a cigarette rod forming portion 62 of the n cigarette machine. The cigarette rod forming portion 62 includes a i2 suction band 63 and a garniture (not shown) which is located at i3 the downstream end (the right hand end as viewed in Figure 2) of i4 the suction band. The suction band 63 conveys a filler stream of is tobacco to the garniture where it is shaped and wrapped with paper i6 to form a cigarette rod. Excess tobacco from the filler stream is i7 trimmed off before the garniture and it is this excess which is is the ecretage. i9 The ecretage tobacco is fed into the hopper 10 via an

20 opening 66 which is fed by an ecretage return pipe 68. An exhaust

2i opening 70 is provided to permit the through-flow of the suction

22 air by means of which the ecretage tobacco is drawn into the

23 hopper. A screen 71 is provided between the openings 66, 70 to

24 prevent the flow of tobacco to the exhaust opening. The exhaust

25 air is fed from the exhaust opening to the suction pipe 33 via a

26 pipe 72. An airlock 74 is provided in the compartment 16 below the

27 opening 66 to prevent tobacco from the chute 45 being sucked into

28 the compartment 16.

29 Referring to Figure 3, a gate valve 80 is provided in the

30 tobacco feed pipe 24 immediately upstream of the point at which 3i the pipe branches to the inlet openings 30, 32. At this point the

32 pipe has a rectangular cross-section and the gate valve comprises

33 a generally planar member pivotally mounted at its downstream end

34 to the pipe 24. The gate valve can be swung across the pipe so as

35 to block one branch of the pipe and at the same time open the

36 other branch. A purge valve indicated at 82 may be provided

37 upstream of the gate valve 80.

38 The purge valve 82 can be opened to allow air at atmospheric 1 pressure to enter the pipe immediately prior to operation of the

2 gate valve. Atmospheric pressure air admitted into the feed pipe

3 via the valve 82 serves to clear any deposits 84 of tobacco from

4 the feed pipe which might otherwise prevent the gate valve from

5 effectively closing off the branches of the pipe 24. β The ecretage return pipe 68 receives ecretage tobacco from

7 the cigarette rod forming portion 62 via a connecting pipe 86 s which is connected to the upstream end of the pipe 68. A further

9 pipe 88 is also connected to the upstream end of the ecretage ιo pipe. The pipe 88 is selectively communicable with a winnowing ii device 90 for returning choke tobacco to the hopper 10 when the i2 machine is in choke clearing mode. The pipe 88 is fed from the i3 winnowing device 90 by a stem clearing pipe 92. In normal i operation of the cigarette making machine, i.e, when it is not in is choke clearance mode, the pipe 92 serves to transmit tobacco stem i6 material from the winnowing device to a stem box (not shown). i7 At the respective junctions 100 where the pipe 88 joins the is pipes 86 and 92, a gate valve generally similar to the gate valve i9 80 is provided.

20 In use, with the gate member 58 in the closed position

2i indicated in Figure 1, the accurate surface 61 of the member forms

22 a floor for the receptacle 12 which is gradually filled with

₂3 tobacco as shown. In order that filling may occur, the gate valve

24 80 is swung over from the position shown in Figure 3 to block the

25 branch 24b and permit tobacco from the primary source to pass

26 along branch 24a through the inlet opening 30 and into the

27 receptacle 12. In order to generate the throughflow of tobacco,

28 the butterfly valve 44 in the air outlet 34 is opened, as shown,

29 so that suction air can pass through the outlet into the suction

30 p ps 33.

3i Whilst the receptacle 12 is filling, the receptacle 14

32 delivers tobacco to the feed mechanism 50 via the chute 45. During

33 emptying of the receptacle 14, the butterfly valve 44 in the air

34 outlet 36 is closed to prevent the suction air in the suction pipe

35 33 from interfering with the discharge flow of tobacco from the

36 receptacle 14.

37 It will be appreciated that as the gate member 58 closes one

38 of the receptacles 12, 14, the other receptacle is opened. Thus by 1 suitable operation of the gate member a continuous supply of

2 tobacco from receptacles 12, 14 to the feed mechanism 50 is

3 provided whereby discontinuities in the flow of tobacco from the

4 primary source are smoothed out.

5 Whilst the receptacles 12, 14 are being filled and emptied,

6 the hopper also receives ecretage tobacco from the cigarette rod making portion 62 via the pipes 86, 68. This tobacco flows into β the hopper via the opening 66 and is moved past the airlock 74 9 into the compartment 16. The flow of tobacco from the compartment ιo 16 is continuous so that the ecretage tobacco merges with the a tobacco discharging from the receptacle 12 or 14. It will be i2 appreciated that the flow of ecretage tobacco provides an i3 additional buffer to assist in providing a continuous flow of i4 tobacco to the feed mechanism 50. is In the event of blockages occurring in a chimney (described i6 in detail in connection with Figure 7) through which tobacco i7 passes from the winnowing device to the cigarette rod making is portion 62 or in the winnowing device 90 itself, the choke tobacco i9 can be fed to the stem pipe 92 and from there into the ecretage

20 pipe 68 via the pipe 88. During choke clearance, the gate valve at

2i the junction 100 of pipes 88 and 92 is operated to divert the flow

22 in pipe 92 along pipe 88 and the gate valve at the junction of

23 pipes 86 and 68 is operated to block the downstream end of the

24 pipe 86 allowing the choke tobacco to pass freely from the pipe 88

25 into the ecretage pipe. It will be understood that in normal

26 operation of the cigarette making machine, the gate valves at the

27 junctions 100 are in the opposite positions to those described

28 above so that the pipe 88 is isolated from both of the pipes 68

29 and 92.

30 Referring now to Figures 4 to 7, another hopper 200 3i according to the invention comprises a housing 202 and a

32 rectangular container 204 disposed in said housing. The container

33 204 has a centrally disposed partitioning wall 205 which serves to

34 divide the container to define two tobacco receiving receptacles,

35 or compartments, 206, 208.

36 The housing 202 has a rectangular opening 210 in its

37 underside which opening extends over substantially the entire

38 length of the housing and leads to a tobacco feed mechanism 212. 1 At its upper end, the housing defines two inlet apertures 214, 216

2 which are connected with respective branches 218a and 218b of a

3 conduit (not shown) by means of which tobacco is supplied to the

4 hopper from a primary source (also not shown). The container 204 s defines respective inlet openings 226, 228 to the compartments

6 206, 208. The openings 226, 228 are at the same height as the

7 inlet apertures 214, 216 so that they may be aligned to define β respective continuous flow passages from the branches 218a, 218b 9 to the compartments 206, 208. One such flow passage extending from ιo the branch 218b to the compartment 206 is shown in Figure 6. ii The container 204 has no base wall and thus the compartments i2 206, 208 are open at their lower ends as viewed in the drawings. i3 The container 204 is movable within the housing 202. As i4 indicated by the arrows 230 in Figures 4 and 5, the container is is slideable back-and-forth in the transverse direction of the i6 housing. i7 In the position of the container shown in Figures 4 and 6, is the compartment 206 has its inlet opening 228 aligned with the i9 housing inlet aperture 216 allowing tobacco to pass from the

2o conduit branch 218b into the compartment. In this position, the

2i lower end of the compartment 206 is covered by the bottom wall of

22 the housing 202. Thus tobacco 236 supplied via the conduit branch

23 218b is able to accumulate in the compartment 206. At the same

24 time the compartment 208 is positioned directly over the opening

25 210 whereby any tobacco stored therein falls into the feed

26 mechanism 212 as indicated by the arrow 238. It will be noted that

27 the opening 210 has substantially the same width as the

28 compartment 208 allowing an uninterrupted flow of tobacco into the

29 feed mechanism at a rate of flow which is controlled by the feed

30 mechanism. As best seen in Figure 6, the inlet opening 226 of the 3i container 204 is not in alignment with either of the branch

32 conduits 218a, 218b and thus whilst the compartment 208 is

33 delivering tobacco to the feed mechanism 212, it cannot receive

34 tobacco from the primary source.

35 If the container is moved to the position shown in Figure 5,

36 the compartment 206 is disposed over the opening 210 and therefore

37 discharges the tobacco 236 stored therein into the feed mechanism

38 as indicated by the arrow 240. At the same time, the inlet opening 1 226 of the compartment 208 is aligned with the housing inlet

2 aperture 214 allowing the passage of tobacco from the conduit

3 branch 218a. The lower end of the compartment 208 is covered by

4 the bottom wall of the housing allowing the tobacco 242 supplied

5 by the branch conduit 218a to accumulate in the compartment.

6 It will be appreciated that by shuttling the container

7 back-and-forth across the housing 202 at suitable intervals, it β can be arranged for one compartment to be filled with tobacco 9 whilst the other discharges to the feed mechanism thereby ιo providing a buffer against discontinuities in the supply of ii tobacco from the primary source. i2 The hopper 200 can be provided with a similar arrangement of i3 screens and exhaust apertures for the receptacles 206, 208 as i those which have been described in conjunction with the is compartments 12 and 14 of the hopper 10 and therefore to avoid i6 unnecessary repetition these will not be described again: these i7 features have not been shown in the drawings to allow these to be is simplified in order to aid understanding of the operation of the i9 hopper 200.

20 As illustrated in Figure 7, the hopper 200 can also be

2i adapted to receive ecretage tobacco. To this end, the compartments

22 206, 208 each have an inlet aperture 248, 250 (shown only in

23 Figure 7) for receiving ecretage tobacco. The ecretage tobacco is

24 fed to the inlet apertures 248, 250 by respective branch pipes

25 252a, 252b of an ecretage pipe 252 which receives the ecretage

26 tobacco from a cigarette rod making portion 292 of the machine.

27 The inlet apertures 248, 250 are at the same height as the inlet

28 openings 226, 228 and are arranged such that as the respective

29 branch conduits 218a, 218b become aligned with the inlet openings

30 226, 228 so do the branch pipes 252a, 252b: i.e, the compartments 3i receive ecretage tobacco when receiving fresh tobacco from the

32 primary source and not when discharging tobacco to the feed

33 mechanism. A valve similar to that shown in Figure 3 can be

3 provided in the pipe 252 at the junction 260 of the branch pipes

35 252a, 252b to divert the flow of ecretage to whichever compartment

36 is in position to receive the tobacco.

37 Referring to Figure 7, the feed mechanism 212 comprises two

38 spiked metering rolls 262 disposed one beside the other and a 1 further spiked roller 264 positioned beneath and centrally of the

2 metering rolls 262. An example of such a feed mechanism 212 can be

3 seen in the Molins Passim cigarette making machine. A passage 268

4 leads from the feed mechanism 212 to the upstream end of a

5 winnowing device 270. β As best seen in Figure 8, the winnowing device 270 comprises

7 a roller 272 disposed at the downstream end of the passage 268 and β a picker roller 274. The roller 272 is provided with spikes 273

9 (indicated in Figure 8) for entraining a layer of tobacco and the ιo picker roller is provided with projections (not shown) by means of ii which it strips tobacco from the roller 272. The width w of the i2 passage 268 corresponds substantially to the radial length of the i3 pins 273. In this context the 'radial length' of the pins 273 is i4 intended to mean the radial distance between the periphery of is roller 272 and the circumference described by the free end of the i6 pins 273 and not the actual length of the pins which, as shown in i7 Figure 8, do not extend radially of the roller. The effect of this is commonality of width and length is to avoid compression of the i9 tobacco fibres picked up by the roller 272. A passage 275 extends

20 downstream from the picker roller 274. A jet block defined by a

2i honeycomb block 276 is arranged at the end of a duct 277 such that

22 an airstream from a fan 280 can be directed into the passage 275

23 at approximately 90° to the axial direction of the passage. The

24 passages 268, 275 define a first path along which tobacco is

25 conducted away from the hopper 200.

26 A passageway 282 extends from the passage 275. The

27 passageway 282 is defined by a lowermost surface 284 which is

28 planar and an upper surface 286 which curves in the lengthwise

29 direction of the passageway such that the height of the passageway

30 decreases as it extends upwardly away from the passage 275. The 3i passageway 282 is generally normal to the passage 275 and has its

32 upstream end positioned opposite the screen 276. At its downstream

33 end the passageway 282 leads into a narrow upwardly extending

34 chimney 290. The chimney 290 leads directly to the suction band of

35 a cigarette rod forming portion 292 of the machine. As shown in

36 Figure 8, the sidewalls of the chimney 290 run parallel to one

37 another. However, as an alternative , it has been found that by

38 arranging the walls such that the flowpath defined by the chimney 1 converges as it approaches the suction band, a desired density of

2 tobacco in the cigarette rod can be more consistently achieved:

3 that is, the standard deviation of the density of the tobacco in

4 the rod is reduced.

5 At the lower end of the passage 275 there is a roller 294

6 which also lies adjacent to a narrow chute 296. The roller 294 is

7 positioned at the upstream end of the chute 296. The chute leads β via an upwardly extending channel 298 to the passageway 282 at a 9 junction with the chimney 290. An air inlet 299 is provided at the ιo end of the channel 298 closest to the chute 296 and another air ii inlet 300 is provided at the lower end of the chute 296. The inlet i2 299 allows a stream of air to be directed upwardly along the i3 channel 298 and the inlet 300 allows a stream of air to be i4 directed upwardly through the chute. Below the air inlet 300 is a is roller 302 and adjacent to it is a pipe 304 which in turn leads i6 to a stem box 306. i7 A connecting pipe 310 extends between the pipe 304 and the is ecretage return pipe 252. The connecting pipe 310 allows the i9 return of choke tobacco from the chimney or various areas of the

20 winnowing device 270 to the hopper 200 via the ecretage pipe 252.

2i Valves similar to that shown in Figure 3 are provided at junctions

22 312, 314 of the connecting pipe 310 and the pipes 252 and 304.

23 These valves allow the connecting pipe to be isolated from the

24 pipes 252 and 304 during normal running of the machine.

25 In use, one of the compartments 206, 208 (Figure 4) is

26 disposed above the opening 210 of the housing in order to

27 discharge the tobacco it contains into the feed mechanism 212.

28 Whilst the one compartment is discharging tobacco it cannot

29 receive ecretage tobacco or tobacco from the primary source. The

30 other compartment meanwhile is filled with ecretage tobacco and 3i fresh tobacco from the primary source.

32 The tobacco discharged into the feed mechanism 212 passes

33 through the spiked metering rolls 262, 264 and into the passage

3 268. The roller 272 continuously removes tobacco from the passage

35 268 and conveys it in a layer to the picker roller 274. The spikes

36 of the picker roller drag tobacco fibres out of the roller 272 and

37 direct them down the passage 275 as a stream of separated fibres.

38 The fibre stream passes through the stream of air emitted from the 1 jet block 276. The passages of the honeycomb jet block have an air

2 straightening effect to produce a distinguishable separation of

3 tobacco at the planar surface 284. The lighter tobacco fibres are

4 entrained in the air stream and conveyed upwardly through the

5 passageway 282 and into the chimney 290 from whence they are drawn

6 onto the suction band of the cigarette rod making device 292. The

7 heavier tobacco fibres pass through the air stream directed out of β the mesh 276 and pass downwardly along the passage 275 to the 9 roller 294 which conveys them into the chute 296. The benefit of ιo the straightened airflow produced by the honeycomb jet block 276 u is that the tobacco fibres passing downwardly along the passage i2 275 are mainly stem material. i3 An airstream passing upwardly through the chute from the air i4 inlet 300 separates the light and heavy tobacco fibres entering is the chute and carries the light fibres to the chimney 290 via the i6 channel 298 where they join with the stream of tobacco fibres i7 exiting the passageway 282. The heavy fibres, typically stem is material, drop onto the roller 302 and are conveyed along the i9 passage 304 to the stem box 306 for removal from the cigarette

20 making machine.

2i The front wall 322 of the chute 296 is arranged to be

22 movable in the lengthwise direction of the chute in order to vary

23 the size of the air inlets 299, 300. Thus by raising the wall

24 upwardly (as viewed in Figure 8) the size of the air inlet 299 is

25 reduced whilst the size of the air inlet 300 is simultaneously

26 increased. By this means the air volumetric flow rate in the chute

27 296 can be varied to adjust stem removal from the winnowing device

28 90.

29 A further feature of the cigarette making machine is an

30 improved facility for clearing choke tobacco. Referring to Figure 3i 9, the front wall 320 of the chimney 290 is pivotable outwardly of

32 the winnowing device 270. By this means the chimney 290 is opened

33 and releases tobacco in the chimney. The arrangement is such that

34 the inner surface of the wall 320 can be brought into alignment

35 with the lower surface 284 of the passageway 282. It will be noted

36 that the lower end of the surface 284 is at a lower level than the

37 jet block 276 so that choke tobacco falls from the chimney into

38 the passageway leading to the roller 294 and does not impinge upon 1 the screen thus avoiding the possibility of the duct 277 becoming

2 filled with tobacco. The choke tobacco is thus reliably directed

3 to the roller 294 at the downstream end of the passage 275.

4 From the roller 294 which also serves as an airlock, the

5 choke tobacco passes down the chute 296 (the blower 280 and

6 suction at the rod making device 292 which induce the airflow at

7 the air inlet 300 are of course turned off or diverted at this β stage) and via the roller 302 into the pipe 304. The valves at the 9 junctions 312 and 314 are switched to put the connecting pipe 310 ιo into flow communication with the pipe 304 and ecretage pipe 252 so π that the choke tobacco can be returned to the hopper 200 via the i2 ecretage return system. The choke tobacco is drawn along the pipes i3 304, 310 and 252 by the suction air which would normally serve to i4 draw ecretage tobacco into the container 204 via the ecretage is return pipe 252. i6 An alternative choke clearing mode of the winnowing device i7 270 is shown in Figure 10. In this mode of operation the chimney is 290 and the walls which define the passageway 282 have been i9 pivoted outwardly of the machine together with the front wall 322

20 of the chute 296 to allow the clearance of choke tobacco from the

2i chute 296. Additionally, the picker roller 274, the drive 324 for

22 the picker roller and a wall 326 which partially defines the

23 passage 268 have all been pivoted in the clockwise direction (as

24 viewed in the drawing) to provide access to the passage 268 and

25 the removal roller 272. Choke tobacco from the chute 296 and/or

26 the roller 272 or the passage 268 are returned to the hopper 200

27 generally as described in connection with Figure 9, i.e, via the

28 roller 302, pipe 304 and the ecretage return system.

29 It will be appreciated that the easy access given by the

30 movable walls and drive parts of the winnowing device 270 3i facilitates the rapid clearance of choke tobacco and this in

32 combination with the direct return of the tobacco to the hopper

33 via the ecretage return system improves the efficiency of the

34 cigarette making machine. Additionally, easy access for general

35 maintenance of the machine is provided.

36 It will also be appreciated that the choke tobacco is

37 returned to the hopper at least in part, and indeed predominantly,

38 along existing pathways in the machine thereby requiring only i minimal additional ducting. Furthermore, the motive forces which

2 convey the tobacco are gravity and pneumatic forces provided by

3 existing fans in the machine which provide the various airflows

4 required for normal running of the machine.

5 It will be understood that as an alternative to having a

6 generally rectangular container shuttling back-and-forth, a hopper

7 could be provided in which the receptacles are rotated β back-and-forth, or through complete revolutions, such that one 9 receptacle is fed with tobacco from a primary source whilst ιo another discharges tobacco to a feed mechanism of a cigarette ii machine. i2 Figure 11 shows in cross-section a diverter valve 350 which i3 could be used with the apparatus illustrated in Figure 2 or Figure i4 7. In the description which follows, the diverter valve 350 will is be described in conjunction with the apparatus shown in Figure 7 i6 and the related drawings, ie Figures 8 to 10. i7 The diverter valve 350 comprises a housing 352 and a body ie 354 which is slidable back-and-forth in the housing 352. The i9 housing defines five bores 356, 358, 360, 362, 364 which are

20 connected with respective pipes which will be described in more

2i detail below. The body 354 defines three passages 366, 368, 370.

22 In the position of the valve shown in Figure 11, the passage 368

23 connects the bore 356 which is defined on one side of the housing

24 352 with the bore 364 which is disposed opposite, the passage 370

25 connects the bore 358 with the opposite bore 360 and the passage

26 366 is blocked by a wall of the housing 352. Likewise the bore 362

27 is blocked by the body 354.

28 In a second position of the valve (not shown), the body 354

29 is arranged such that the passage 366 connects the bore 356 with

30 the bore 362 via the passage 368 and the bores 358, 360 and 364 3i are blocked by the body 354.

32 The body 354 is slid back-and-forth between its two

33 operative positions by means of a pneumatic cylinder 370 which is

34 activated by a 3/3 pneumatic control valve 372. The pneumatic

35 cylinder 370 is a so-called double acting cylinder and includes a

36 piston 374 connected to a piston rod 376 which is connected to the

37 body 354 by means of a swivel-joint 378.

38 The 3/3 pneumatic control valve 372 is of a type well known 1 to those skilled in the art and is arranged to supply air under

2 pressure to opposite sides of the piston 374 by means of

3 respective supply lines 380, 382.

4 The diverter valve 350 is arranged to replace the separate

5 valves provided at the junctions 312, 314 (described above in β connection with Figure 8) and makes redundant the pipe 310. 7 Referring to Figures 8 and 11, the upstream end of the stem pipe β 304 feeds from the roller 302 and is connected to the housing 352 9 so as to feed into the bore 356. On the opposite side of the ιo housing, a downstream portion of the pipe 304 continues from the ii bore 364 and feeds into the stem box 306. An upstream end portion i2 of the ecretage return pipe 252 extends from the cigarette rod i3 forming portion 292 and feeds into the bore 358. A downstream end i4 portion of the pipe 252 extends from the opposite side of the is housing 352 where it is connected in-line with the bore 360 and ie extends from the bore 360 to the hopper 200. A feed-in pipe 386 i7 extends from the bore 362 and feeds into the downstream portion of is the ecretage return pipe 252. i9 Figure 11 shows the diverter valve in position in which it

20 is held during normal operation of the cigarette making machine.

2i In this position, ecretage tobacco from the cigarette rod forming

22 portion 292 of the cigarette making machine is returned to the

23 hopper 200 via the ecretage return pipe 252 and the bores 358, 360

24 and the passage 370 which define a continuous tobacco conveying

25 path to the hopper. At the same time, stem from the winnowing

26 device 270 passes to the stem box via a continuous conveying path

27 defined by the pipe 304, bores 356, 364 and the passage 368.

28 In the event of the cigarette making machine being stopped

29 to clear choke tobacco from the chimney 290, chute 296 or passage

30 268, the pneumatic control valve 372 is switched electrically to 3i supply pressurised air to the lefthand side (as viewed in Figure

32 11) of the piston 374 and exhaust the pressurised air acting on

33 the righthand side of the piston. The piston then drives the body

34 354 into its second position in which the passage 366 is in-line

35 with the bore 356 and the passage 368 is in-line with the bore

36 362, the other bores 358, 360, 364 being blocked by the body 354.

37 In this condition, the choke tobacco is pneumatically conveyed (as

38 described above) into the stem pipe 304 via the roller 302. From 1 here, the choke tobacco is conveyed along the pipe 304 to the

2 hopper 200 via the bore 356, passages 366, 368, bore 362, feed-in

3 pipe and the downstream portion of the ecretage return pipe 252.

4 When the choke has been cleared, the body 354 is returned to

5 the position shown in Figure 11 in response to electrical signals

6 to the pneumatic control valve 372.

7 It will be appreciated that the diverter valve 350 allows β for a compact arrangement for pneumatic conveying of the 9 ecretage, stem and choke material in the cigarette machine and ιo avoids the need to need to have two junctions 312,314 each with ii its own switching valve. It will be appreciated that if it is i2 desired to retain the pipe layout shown in Figure 8, simple 2/1 i3 and 1/2 diverter valves could be used. Likewise, the flap valve i4 shown in Figure 3 could be replaced by a 1/2 diverter valve. is Diverter valves per se are well known to those skilled in the art ie and will not be described further herein.

17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38

Claims

l CLAIMS

2

3 1. A cigarette making machine comprising a hopper for recei ving tobacco from a primary source , an upwardly extending s passage for conducting tobacco to a cigarette rod making portion β of the machine and means for conducting tobacco from sa id hopper 7 to said passage, the arrangement being such that choke tobacco in β said passage and/or said conducting means can be returned to said 9 hopper at least in part by means of a pneumatic force.

10 ii 2. A mach ine as claimed in claim 1 , further comprisi ng i2 ecretage duct means for conducting ecretage tobacco from said i3 cigarette rod mak ing port ion to said hopper wherei n said choke i4 tobacco i s returned to sa i d hopper at l east i n part v i a sai d is ecretage duct means.

16 i7 3. A machine as claimed in claim 1 or 2, further is comprising stem duct means for conducting stem material away from i9 said conducting means, wherein said choke tobacco is returned to

20 said hopper at least in part via said stem duct means.

21

22 4. A machine as claimed in claim 3 when dependent on

23 claim 2, further comprising connecting duct means connecting said

24 ecretage duct means and said stem duct means.

25

26 5. A machine as claimed in claim 4, comprising valve

27 means associated with said connecting duct means for isolating

28 said stem duct means from said ecretage duct means during normal

29 running of the machine.

30

3i 6. A mach ine as claimed in claim 4 or 5 , wherein choke

32 tobacco in said conducting means i s returned to said hopper by

33 means of said pneumatic force v i a sa id stem duct means , sai d

3 connecting duct means and said ecretage duct means.

35

36 7. A mach i ne as c l a imed i n any one of the precedi ng

37 claims , further compri sing at least one suction fan arranged to

38 draw air through said hopper, the airflow generated by the or each l said fan providing said pneumatic force.

2

3 8. A machine as claimed in any one of the preceding

4 claims, wherein a wall which partly defines said passage and/or a

5 wall which partly defines said conducting means is pivotable to

6 positions which open said passage or a path defined by said

7 conducting means for releasing choke tobacco therein.

8

9 9. Apparatus for use in manufacturing cigarettes, the ιo apparatus comprising a reservoir for receiving tobacco from a ii primary source, means for forming a cigarette rod, means for i2 conducting tobacco from said reservoir to said rod forming means i3 and return duct means for returning choke tobacco from said i4 conducting means to said reservoir, said conducting means being is defined by at least one wall which is movable to open a respective ie portion of said conducting means to_^permit the release of choke i7 tobacco in said portion and the arrangement being such that said ie choke tobacco can be conveyed to said reservoir via said i9 conducting means and said return duct means.

20

2i 10. Apparatus as claimed in claim 9, wherein said choke

22 tobacco can be conveyed to said reservoir at least in part by

23 means of a pneumatic force.

24

25 11. Apparatus as claimed in claim 9 or 10, wherein said

26 conducting means comprises a plurality of walls arranged to define

27 an upwardly extending chimney leading to said rod forming means, a

28 first path for conducting tobacco away from said reservoir, and a

29 second path leading from said first path to said chimney, and a

30 said wall which partially defines said chimney is pivotable to a 3i position in which choke tobacco from said chimney can fall into 32 said second path for return to said reservoir.

33

34 12. Apparatus as claimed in claim 11, wherein said first

35 path extends downwardly from said reservoir.

36

37 13. Apparatus as claimed in claim 12, wherein said second

38 path, at least initially, is substantially perpendicular to said l first path.

2

3 14. Apparatus as claimed in claim 11, 12 or 13, wherein

4 said conducting means comprises means for directing an airstream

5 across said first path into said second path to convey tobacco β from said first path to said chimney via said second path.

7 β 15. Apparatus as claimed in any one of claims 11 to 14, wherein a lowermost surface of said second path is defined by a ιo said wall which is substantially planar at least in its lengthwise ii direction and said pivotable wall of said chimney is pivotable to i2 a position in which it is aligned with said surface.

13 i4 16. Apparatus as claimed in any one of claims 11 to 15, is further comprising stem duct means for conducting stem material ie away from said conducting means, wherein an upstream end portion i7 of said return duct means is defined by at least a portion of said ie stem duct means.

19

20 17. Apparatus as claimed in claim 16, wherein said

2i conducting means defines a third path which extends upwardly from

22 a downstream end of said first path to said chimney and downwardly

23 from said downstream end to said stem duct means, and further

24 comprises means for directing an airstream upwardly along said

25 third path from a position below said downstream end, the

26 arrangement being such that choke tobacco falling into said second

27 conveying path is conducted to said stem duct means via said first

28 path and said third path.

29

30 18. Apparatus as claimed in claim 17, wherein a said wall

3i which partially defines said third path is pivotable outwardly of

32 said third path to open said third path to release choke tobacco

33 therein.

34

35 19. Apparatus as claimed in claim 18, wherein said

36 pivotable wall which partially defines said third path carries the

37 said walls which define said chimney and said second path and at

38 least one wall which partially defines said first path, the 1 arrangement being such that when said wall which partially defines

2 said third path is pivoted outwardly of the third path, at least a

3 downstream portion of said first path is opened to permit the

4 clearance of choke tobacco therein.

5

6 20. Apparatus as claimed in claim 19, further comprising

7 roller means for acting on tobacco in said first path upstream of β said second path, said roller means comprising a first roller 9 adapted to entrain a layer of tobacco and a second roller for ιo stripping tobacco from said first roller and directing said ii stripped tobacco along said first path and downstream of said i2 roller means.

13 i 21. Apparatus as claimed in claim 20, wherein said second is roller and a wall which partially defines a portion of said first ie path upstream of said roller means are arranged to be pivotable i7 together outwardly of said first path to open said first path ie upstream of said roller means to permit the clearance of choke i9 tobacco therein.

20

2i 22. Apparatus as claimed in any one of claims 16 to 21,

22 further comprising ecretage duct means for returning ecretage

23 tobacco from said rod forming means to said reservoir and

2 connecting duct means connecting said stem duct means and said

25 ecretage duct means, wherein said connecting duct means and at

26 least a portion of said ecretage duct means define a downstream

27 end portion of said return duct means.

28

29 23. Apparatus as claimed in claim 22, further comprising

30 valve means associated with said connecting duct means for 3i isolating said stem duct means from said ecretage duct means under 32 normal use conditions of the apparatus.

33

3 24. Apparatus as claimed in any one of claims 9 to 23,

35 wherein said reservoir comprises a hopper as claimed in any one of

36 claims 26 to 41.

37

38 25. A cigarette making machine comprising a hopper for 1 receiving tobacco from a primary source, an upwardly extending

2 passage for conducting tobacco to a cigarette rod making portion

3 of the machine and means for conducting tobacco from said hopper

4 to said passage, said passage being defined by a plurality of

5 walls at least one of which is movable outwardly of the passage to

6 allow choke tobacco in the passage to fall to a collection space

7 from which such choke tobacco is returnable to said hopper by β pneumatic or other conveyance means.

9 lo 26. A hopper for a cigarette making machine, said hopper ii comprising at least two receptacles for receiving tobacco from a i2 primary source and said receptacles being selectively communicable i3 with a feed mechanism of said machine such that each can discharge i4 tobacco housed therein for delivery to said feed mechanism while is the other or at least one of the other said receptacles receives ie tobacco from said primary source and is substantially prevented i7 from discharging to said feed mechanism.

18 i9 27. A hopper as c l a i med i n c l a i m 26 , where i n sa i d

20 receptacles are disposed in side-by-side relationship.

21

22 28. A hopper as c l a imed i n c l a im 26 or 27 , further

23 compr i s i ng va l ve means for se l ect i ve ly commun i cat i ng sa i d

24 receptacles with said feed mechanism.

25

26 29. A hopper as claimed in claim 28, wherein said valve

27 means is adapted to define at least a portion of a floor of at

28 least one said receptacle when in a position in which the

29 discharge of tobacco from the or each said receptacle is

30 prevented.

31

32 30. A hopper as claimed in claim 29, wherein said valve

33 means comprises a gate member pivotable between a first position

34 in which it defines at least a portion of a floor of a first said

35 receptacle and a second position in which it defines at least a

36 portion of a floor of a second said receptacle.

37

38 31. A hopper as claimed in claim 26 or 27, further 1 comprising means defining a housing for said receptacles and,

2 associated with said housing means, means for guiding tobacco

3 discharged from said receptacles to said feed mechanism, said

4 receptacles each having at least one outlet opening provided in a

5 lower end region thereof and being movable relative to said

6 housing means to respective positions in which the or each outlet opening is in flow communication with said guiding means and β positions in which said flow is interrupted.

9 ιo 32. A hopper as claimed in claim 31, wherein said ii receptacles are slideable in the transverse direction of said i2 housing means.

13 i4 33. A hopper as claimed in claim 31 or 32, wherein each is said receptacle has an inlet opening in an upper end region ie thereof and further comprising respective inlet means for feeding i7 tobacco from said primary source to said inlet openings, said ie inlet means being associated with said housing means and the i9 arrangement being such that when a said receptacle is in flow

20 communication with said guiding means, the inlet opening of the or

2i at least one other said receptacle is in flow communication with

22 the respective said inlet means.

23

24 34. A hopper as claimed in claim 33, further comprising

25 two said receptacles defined by a container having a dividing wall

26 therein, said container being movable between respective positions

27 in which whilst one receptacle is in flow communication with said

28 guiding means, the other said receptacle is fed with tobacco from

29 said primary source via the respective said inlet means.

30

3i 35. A hopper as claimed in claim 31, 32 or 33, wherein

32 said receptacles are integral.

33

34 36. A hopper as claimed in any one of claims 26 to 35,

35 further comprising means for receiving ecretage tobacco.

36

37 37. A hopper as claimed in claim 36 when dependent on any

38 one of claims 26 to 30 , further comprising a compartment for 1 receiving said ecretage tobacco, said compartment being in open

2 flow communication with said feed mechanism.

3 38. A hopper as claimed in claim 36 when dependent on any

5 one of claims 31 to 35, wherein each said receptacle comprises an

6 ecretage receiving inlet, the arrangement being such that each

7 receptacle receives ecretage tobacco when flow between the or each β outlet thereof and said guiding means is interrupted.

9 ιo 39. A hopper for a cigarette making machine comprising two ii receptacles disposed side-by-side for receiving tobacco from a i2 primary source, the arrangement being such that whilst one said i3 receptacle receives and stores tobacco from said primary source, i4 the other said receptacle discharges tobacco stored therein to a is feed mechanism of said machine.

16 i7 40. A hopper as claimed in claim 39, wherein said ie receptacles each have a discharge opening at a lower end thereof i9 and further comprising a valving member movable between a first

20 position in which it blocks the said discharge opening of one said

2i receptacle and a second position in which it blocks the said

22 discharge opening of the other said receptacle.

23

24 41. A hopper as claimed in claim 39, further comprising a

25 housing and a container disposed in said housing, said container

26 defining said receptacles and being slideable back and forth

27 within said housing between positions in which alternately one

28 said receptacle receives tobacco from said primary source whilst

29 the other said receptacle discharges tobacco to said feed

30 mechanism.

31 32 33 34 35 36 37 38