Conveying of cigarettes and other rod-like articles

Abstract

Tray filling or unloading machine includes a junction zone from which cigarettes pass into a delivery channel (e.g. a chute); means for delivering articles into the junction zone; and a reservoir comprising a conveyor for carrying a stack of articles into or from the junction zone as required, the speeds of the conveyor while moving in opposite directions being different, so that the reservoir absorbs or discharges articles at the full rate at which the machine is capable of handling articles while each tray is being replaced by the next, and discharges or absorbs the articles at other times at a slower speed.

Description

This invention is particularly concerned with tray systems for cigarettes, but can also be used in connection with similar rod-like articles, for example cigarette filter rods and smokable rods other than cigarettes. The term "cigarette" will for convenience be used throughout this specification and is intended to include other similar rod-like articles.

Tray systems for cigarettes commonly involve occasional temporary stoppage of the flow of the cigarettes while each tray is being replaced by the next tray. For example, in a tray filling machine the delivery of cigarettes to the filling position stops while each full tray is being replaced by the next tray ready for filling; on the other hand, in a tray unloading machine (i.e. for emptying trays) it may be desirable (as described for example in U.S. Pat. No. 3,759,408) to stop withdrawing cigarettes in the region of the unloading hopper while each empty tray is being replaced by the next full tray to reduce the distance through which the cigarettes from the full tray must drop onto the surface of the cigarettes remaining from the previous tray.

According to a first aspect of the present invention a tray filling or unloading machine includes a junction zone from which cigarettes pass into a delivery channel (e.g. a chute); means for delivering articles into the junction zones; and a reservoir comprising a conveyor for carrying a stack of articles into or from the junction zone as required, the speeds of the conveyor while moving in opposite directions being different, so that the reservoir absorbs or discharges articles at the full rate at which the machine is capable of handling articles while each tray is being replaced by the next, and discharges or absorbs the articles at other times at a slower speed. The delivery channel and reservoir conveyor may extend respectively downwards and substantially horizontally from the junction zone. Alternatively, the reservoir may comprise two vertically movable bands extending downwards from the junction zone and carrying a wall forming the bottom end of the reservoir, and the delivery channel may extend horizontally from the junction zone; such an arrangement is described in patent application Ser. No. 408,256 filed Oct. 23, 1973.

In the case of a tray filling machine, while each full tray is being replaced by an empty tray, the reservoir receives all the articles which are delivered into the junction zone, for example by a cigarette or filter rod making machine, for which purpose the reservoir conveyor moves at a relatively high speed away from the junction zone. Then while the next tray is being filled, the reservoir conveyor moves relatively slowly towards the junction zone so that the reservoir is substantially empty by the time the tray is full, so as to be ready to receive the full flow of articles into the junction zone while the next tray change is taking place.

In the case of a tray-unloading machine, the articles are preferably carried horizontally out of each tray in turn on a delivery conveyor, preferably in stack formation, and are delivered by the delivery conveyor to a junction zone above a chute. While the delivery conveyor is delivering articles into the junction zone, the reservoir conveyor moves slowly away from the junction at a speed such that the reservoir is substantially full by the time the tray has emptied. Then while the empty tray is being replaced by a full tray (during which period the delivery conveyor is stopped) the reservoir conveyor moves at a relatively fast speed towards the junction zone to deliver articles at the rate at which the articles are required to pass down the chute.

Preferably the movement of the reservoir conveyor in both directions is controlled by a sensor (for example, a pivoted plate) above the junction zone to maintain the level of articless in the junction zone within predetermined limits.

According to another aspect of this invention, a tray filling machine delivers the cigarettes as a wide stack (corresponding to the width of a tray) moving downwards into the tray, the wide stack being formed by delivering the cigarettes into a junction zone from which the cigarettes are fed along two downwardly diverging channels from the lower outlet ends of which the cigarettes of each channel are spread horizontally, for example by rollers, to form the wide stack. There is preferably a reservoir communicating with the junction zone in accordance with the first aspect of this invention.

Examples of arrangements according to the invention are shown in the accompanying drawings wherein:

FIG. 1 shows a tray filling system according to the invention;

FIG. 2 is a diagrammatic illustration of a drive system suitable for a tray filling system as shown in FIG. 1; and

FIG. 3 shows diagrammatically a tray unloader according to the invention.

As shown in FIG. 1 a single row of cigarettes 2 is fed sideways between delivery bands 4 and 6 which move along a curved path defined by a fixed member 8 in contact with the band 6. Tension in the bands (and particularly the band 4) results in the cigarettes being gripped between the bands so that they can be fed firmly into a junction zone 10. Above this junction zone there is a sensor comprising intermeshing arms 12 and 14 which are pivoted at 12A and 14A so as to be able to move up and down in response to the pressure of cigarettes in the junction zone 10.

The two sensor arms may be linked by a lost-motion linkage to a common conveyor control mechanism, basically as described in U.S. Pat. No. 3,561,585 dated Feb. 9, 1971. Alternatively, in a preferred arrangement each arm may be arranged to operate one switch when it reaches a lower limit (i.e. approximately as shown in solid outline) and a second switch when it reaches an upper limit (shown in dotted and dashed outline); the operation of the sensor will be described further on.

Opposite the cigarette delivery bands 4 and 6 there is a reservoir formed basically by a reversible conveyor band 16 to which is attached an end wall 18. The reservoir also includes a top band 20 which is driven at the same speed and in the same direction as the band 16 to define the top surface of the cigarette stack 21 in the reservoir. The bands 16 and 20 pass round pulleys 16A, 16B, 20A, 20B as shown.

From the junction zone 10 the cigarettes pass downwards towards a tray filling device (not shown) which is basically as described in British patent specification No. 1,093,532 (U.S. Pat. No. 3,320,717). On the way down to the tray filling device, the flow of cigarettes divides so as to pass downwards along opposite sides of a flow divider 26. More specifically, the cigarettes pass downwards as two similar stacks 28 and 30 which re-combine below the flow divider 26 to form a wide stack corresponding to the width of the trays to be filled. The flow divider 26 basically comprises three walls 26A, 26B and 26C but includes also rollers 32 and 34 which rotate in the directions shown to assist the cigarettes from the stacks 28 and 30 to move inwards below the bottom wall 26C.

The top corner of the flow divider 26 is formed by a manually rotatable roller 36 including a groove 36A. This roller 36 is used to extract a cigarette from the general flow when necessary for inspection, for which purpose the roller 36 is turned manually through one revolution, so that a cigarette falls into the groove 36A and then drops out of the groove and onto the bottom wall 26C, from which position it can readily be removed.

FIG. 1 just shows the top ends of two vertical walls 36 and 38 which confine the sides of the wide stack of cigarettes moving into the tray filling device below.

While a tray is being filled, the reservoir conveyor bands move slowly to the left so as to deliver cigarettes at a rate of 600 per minute into the junction zone 10. The bands 4 and 6 deliver cigarettes continuously from a cigarette making machine at a rate of, for exmaple, 4,000 per minute. Thus a total of 4,600 cigarettes per minute passes down from the junction zone and into the tray. If, at any moment, both sensor arms reach their upper limits, operation of both the upper limit switches results in the reservoir bands stopping; as soon as both arms drop and thus release their corresponding upper limit switches, the reservoir bands start again, at the set speed, to deliver cigarettes into the junction zone.

The capacity of the reservoir and the speed of its bands are such that the end wall 18 is nearly at its extreme left position (corresponding to the reservoir-empty condition) by the time the tray is full. A master switch (not shown) is operated automatically by a sensor when the tray is full, and this results in the full tray being moved away and being replaced by an empty tray, during which changeover period the reservoir bands are driven in the opposite direction to draw cigarettes into the reservoir at a rate of 4,000 per minute (i.e. equal to the rate at which cigarettes continue to be delivered to the junction zone by the bands 4 and 6); the flow of cigarettes downwards from the junction zone is stopped during the tray changeover period, for example as described in British patent specification No. 1,093,532.

During the tray changeover period, if both sensor arms at any moment reach their lower limiting positions, the operation of the lower limit switches results in the reservoir bands stopping; the bands start again when both arms rise and release their lower limit switches.

The two speed drive of the reservoir bands (i.e. in opposite directions) may be achieved as shown in FIG. 2. Similar gear wheels 40 and 42 are connected respectively to the pulleys 20A and 16A. These gear wheels are interconnected via two idler gear wheels 44 and 46 (rotating about fixed axes) so that the two-pulleys always rotate at the same speed but in opposite directions. Also connected to the two pulleys 20A and 16A are two drive pulleys 44B and 46B which are driven in the same direction via belts 48 and 50 from a drive motor 52, the speeds of the two pulleys 44B and 46B corresponding respectively to the slow and fast motions required of the reservoir bands. The pulleys 44B and 46B drive the pulleys 20A and 16A through unidirectional couplings 44A and 46A. Thus the motor automatically transmits a fast drive to both bands when running in one direction (clockwise) and a slow drive when running in the opposite direction. It will be understood that the unidirectional coupling 46A can only transmit a drive (fast) in a clockwise direction, whereas the coupling 44A can only transmit a drive (slow) in an anticlockwise direction.

In the event of the wall 18 reaching a position in which it obscures a photo cell 22 (FIG. 1), a signal is derived from the photo cell 22 to indicate that the reservoir is nearly full. In the event of the wall 18 reaching its extreme right position, it obscures a photo cell 24 which automatically stops the whole machine.

The double arm sensor comprising the arms 12 and 14 may be replaced by a single arm sensor resting more or less centrally on the cigarettes in the junction zone 10.

FIG. 3 shows diagrammatically a tray unloader according to this invention. Each tray 54 in turn is inverted at an unloading position (as shown) so that a stack of cigarettes 56 can be carried away by a conveyor 58 towards a junction zone above a chute 59 leading to a packing machine. While each tray is being unloaded, a pair of reservoir conveyors 60 and 62 with an end wall 64 draw cigarettes slowly from the junction zone, under the control of a sensor 66, so that the reservoir is substantially full by the time the tray has been emptied. Then while the empty tray is being replaced by a full tray, the conveyors 60 and 62 move more rapidly in the opposite direction (i.e. to the right) to deliver the cigarettes back into the junction zone to continue the supply of cigarettes to the packing machine through the chute 59.

Claims

We claim:

1. A cigarette tray handling machine including means defining a junction zone; means defining a delivery channel for receiving a stack of cigarettes from said junction zone, said delivery channel having a width sufficient to accommodate a plurality of cigarettes in side-by-side relation; means for delivering cigarettes into the junction zone; and a reservoir comprising a conveyor for carrying a stack of cigarettes into or from the junction zone as required, and means for continuously driving the conveyor at a first predetermined speed while moving in one direction and at a second predetermined speed while moving in the opposite direction, so that the reservoir absorbs or discharges cigarettes at the full rate at which the machine is capable of handling cigarettes while each tray is being replaced by the next tray, and discharges or absorbs the cigarettes at other times at a slower speed.

2. A machine according to claim 1 further comprising sensor means for detecting the level of cigarettes in said junction zone and to control movement of the reservoir conveyor in both directions to maintain the level of cigarettes in the junction zone within predetermined limits.

3. A machine according to claim 1 in which the delivery channel extends downwards from the junction zone, and in which the reservoir conveyor extends substantially horizontally from the junction zone.

4. A machine according to claim 3 including a top band which is parallel to the reservoir conveyor to confine the upper surface of the stack of cigarettes in the reservoir and means for concurrently driving said top band in the same direction and at the same speed as said reservoir conveyor.

5. A machine according to claim 1 wherein said means for delivering cigarettes into the junction zone comprises parallel bands arranged to grip the cigarettes in a single row between them and deliver the single row of cigarettes into the junction zone.

6. A cigarette tray filling machine including means defining a junction means; means defining a delivery channel for receiving a stack of cigarettes from said junction zone, said delivery channel having a width sufficient to accommodate a plurality of cigarettes in side-by-side relation; means for delivering cigarettes into the junction zone; and a reservoir comprising a conveyor for carrying a stack of cigarettes into or from the junction zone as required, and means to continuously drive the conveyor in a first direction at a first, high predetermined speed from a substantially predetermined starting position, whereby the reservoir absorbs cigarettes at the full rate at which the machine is capable of receiving cigarettes while each tray is being replaced by the next tray, and in the opposite direction at other times at a second, slower, predetermined speed, whereby the reservoir conveyor gradually returns to the starting position from which it can again begin to receive cigarettes at said full rate for a predetermined period.

7. A machine according to claim 6 wherein said means for driving the conveyor comprises reversible drive means for selectively driving said conveyor in said first and opposite directions and different-ratio transmission means for selectively driving said conveyor at said first and second predetermined speeds.

8. A machine according to claim 7 further comprising means for exchanging trays.

9. A machine according to claim 6 wherein said means defining a delivery channel comprises wall means defining a channel below and communicating with said junction zone, said wall means including two walls at opposite sides of said channel which diverge in the downward direction from said junction zone to a point where the distance between said two walls is substantially the same as the width of a tray, and a flow divider positioned in said channel between said diverging walls forming two downwardly diverging channels, each defined by said flow divider and one of said diverging walls, whereby the stream of cigarettes moving downwardly from said junction zone is divided into two narrower streams by said flow divider, said narrower streams flowing through said respective downwardly diverging channels and merging to form a single wide stack of cigarettes in said channel below said flow divider.

10. A machine according to claim 9 wherein said flow divider comprises a longitudinal member extending substantially parallel to said two diverging walls, said member including two further diverging walls, each said further diverging wall defining with one of said diverging walls one of said diverging channels and rotatably driven means along the lower edge of each of said further diverging walls for directing cigarettes from said diverging channels beneath said flow divider to form said wide stack of cigarettes.

11. A cigarette tray unloading machine including means defining a junction zone; means defining a delivery channel for receiving a stack of cigarettes from said trays, said delivery channel having a width sufficient to accommodate a plurality of cigarettes in side-by-side relation; means for delivering cigarettes into the junction zone; and a reservoir comprising a conveyor for carrying a stack of cigarettes into or from the junction zone as required, and means to continuously drive the conveyor in a first direction at a first, high predetermined speed from a substantially predetermined starting position, whereby the reservoir discharges cigarettes at the full rate at which the machine is capable of delivering cigarettes while each tray is being replaced by the next tray, and in the opposite direction at other times at a second, slower, predetermined speed, whereby the reservoir conveyor gradually returns to the starting position from which it can again begin to discharge cigarettes at said full rate for a predetermined period.

12. A machine according to claim 11 wherein said means for driving the conveyor comprises reversible drive means for selectively driving said conveyor in said first and opposite directions and different-ratio transmission means for selectively driving said conveyor at said first and second predetermined speeds.

13. A machine according to claim 12 further comprising means for exchanging trays.

14. A machine for loading cigarettes and other rod-like articles into a sequence of trays comprising:

a. means defining a junction zone for containing said articles at a substantially constant rate,

b. means for delivering said articles into said junction zone,

c. means defining a delivery channel for receiving a stack of said articles from said junction zone and delivering said articles to said trays, said delivery channel having a width sufficient to accommodate a plurality of cigarettes in side-by-side relation, and

d. a reservoir communicating with said junction zone and comprising a conveyor for carrying a stack of said articles into and from said junction zone and means for continuously driving the conveyor in a direction away from said junction zone at a fast predetermined speed sufficient to absorb said articles at the full rate at which the machine is capable of handling said articles while each tray is being replaced by the next tray and for driving the conveyor in the opposite direction towards said junction zone at a slower predetermined speed to discharge said absorbed articles into said junction zone while each tray is being filled.

15. A machine according to claim 14 further comprising sensor means for detecting the level of cigarettes in said junction zone and to control movement of the reservoir conveyor in both directions to maintain the level of cigarettes in the junction zone within predetermined limits.

16. A machine according to claim 14 wherein said means defining a delivery channel comprises wall means defining a channel below and communicating with said junction zone, said wall means including two walls at opposite sides of said channel which diverge in the downward direction from said junction zone to a point where the distance between said two walls is substantially the same as the width of a tray, and a flow divider positioned in said channel between said diverging walls forming two downwardly diverging channels, each defined by said flow divider and one of said diverging walls, whereby the stream of articles moving downwardly from said junction zone is divided into two narrower streams by said flow divider, said narrower streams flowing through said respective downwardly diverging channels and merging to form a single wide stack of articles in said channel below said flow divider.

17. A machine according to claim 16 wherein said flow divider comprises a longitudinal member extending substantially parallel to said two diverging walls, said member including two further diverging walls, each said further diverging wall defining with one of said diverging walls one of said diverging channels and rotatably driven means along the lower edge of each of said further diverging walls for directing articles from said diverging channels beneath said flow divider to form said wide stack of articles.

18. A machine for unloading cigarettes and other rod-like articles from a sequence of trays comprising:

a. means defining a junction zone for containing said articles,

b. means defining a delivery channel for receiving a stack of said articles from said trays and delivering said articles to said junction zone, said delivery channel having a width sufficient to accommodate a plurality of cigarettes in side-by-side relation,

c. means for discharging said articles from said junction zone at a substantially constant rate, and

d. a reservoir communicating with said junction zone and comprising a conveyor for carrying a stack of said articles into and from said junction zone and means for continuously driving said conveyor in a direction away from said junction zone at a slow predetermined speed sufficient to absorb some of said articles from said junction zone while each tray is being discharged into said delivery channel and for driving the conveyor in the opposite direction towards said junction zone at a faster predetermined speed to discharge said absorbed articles into said junction zone while each tray is being replaced by the next tray.

19. A machine according to claim 18 further comprising sensor means for detecting the level of cigarettes in said junction zone and to control movement of the reservoir conveyor in both directions to maintain the level of cigarettes in the junction zone with predetermined limits.

20. A machine according to claim 1 wherein said means for driving the conveyor comprises reversible drive means for selectively driving said conveyor in said one and opposite directions and different-ratio transmission means for selectively driving said conveyor at said first and second predetermined speeds.

21. A machine according to claim 20 further comprising means for exchanging trays.

22. A cigarette tray handling machine including means defining a junction zone; means defining a delivery channel for receiving cigarettes from said junction zone; means for delivering cigarettes into the junction zone; a reservoir comprising a conveyor for carrying a stack of cigarettes into or from the junction zone as required; and means for driving the conveyor, comprising a reversible motor, different-ratio transmissions, and a plurality of unidirectional clutches to selectively drive said reservoir conveyor at different predetermined speeds while moving respectively in opposite directions; so that the reservoir absorbs or discharges cigarettes at the full rate at which the machine is capable of handling cigarettes while each tray is being replaced by the next tray, and discharges or absorbs the cigarettes at other times at a slower speed.

23. A machine according to claim 22 in which the delivery channel extends downwards from the junction zone, and in which the reservoir conveyor extends substantially horizontally from the junction zone.

24. A machine according to claim 23 including a top band which is parallel to the reservoir conveyor to confine the upper surface of the stack of cigarettes in the reservoir and means for concurrently driving said top band in the same direction and at the same speed as said reservoir conveyor.

25. A machine according to claim 22 further comprising sensing means to detect the level of cigarettes above said junction zone and to control movement of the reservoir conveyor in both directions to maintain the level of cigarettes in the junction zone between predetermined limits.

26. A machine according to claim 22 in which said means for delivering cigarettes into the junction zone comprises parallel bands arranged to grip the cigarettes in a single row between them and deliver the single row of cigarettes into the junction zone.

27. A machine according to claim 22 further comprising means for exchanging trays.

28. A cigarette tray filling machine including means defining a junction zone; means defining a delivery channel adapted to receive a stack of cigarettes from said junction zone and carry the stack towards a tray; means for delivering cigarettes into the junction zone; a reservoir comprising a conveyor for carrying a stack of cigarettes into or from the junction zone as required; and driving means for continuously driving the conveyor in a direction away from the junction zone at a faster speed sufficient to absorb cigarettes at the full rate at which the machine is capable of receiving cigarettes while each tray is being replaced by the next tray, and towards the junction zone at other times at a slower speed so that the reservoir conveyor gradually returns to its starting position from which it can again begin to receive cigarettes at said full rate when the next tray is changed.

29. A machine according to claim 28 wherein said means for driving the conveyor comprises reversible drive means for selectively driving said conveyor both away from the junction zone and towards the junction zone and different-ratio transmission means for selectively driving said conveyor at said faster speed and said slower speed respectively.

30. A cigarette tray filling machine according to claim 28 in which said driving means is adapted to drive the reservoir conveyor at different predetermined speeds in different directions.

31. A cigarette tray filling machine according to claim 28 arranged to deliver cigarettes as a wide stack, corresponding to the width of a tray, in a downward direction into the tray, the delivery channel including wall means defining a channel below and communicating with said junction zone, said wall means including two walls at opposite sides of said delivery channel which diverge in the downward direction from said junction zone to a point where the distance between said two walls is substantially the same as the width of a tray, and a flow divider positioned in said channel between said diverging walls forming two downwardly diverging channels, each defined by said flow divider and one of said diverging walls, whereby the stream of cigarettes moving downwardly from said junction zone is divided into two narrower streams by said flow divider, said narrower streams flowing through said respective downwardly diverging channels and merging to form a single wide stack of cigarettes in said channel below said flow divider.

32. A cigarette tray filling machine according to claim 31 in which said flow divider comprises a longitudinal member extending substantially parallel to said two diverging walls, said member including two further diverging walls, each said further diverging wall defining with one of said diverging walls one of said diverging channels and rotatably driven means along the lower edge of each of said further diverging walls for directing cigarettes from said diverging channels beneath said flow divider to form said wide stack of cigarettes.

33. A cigarette tray filling machine according to claim 28 including sensing means to sense the level of cigarettes in the junction zone, said driving means being controlled in response to a signal derived from said sensing means.

34. A cigarette tray unloading machine including means defining a junction zone, means defining a delivery channel for receiving a stack of cigarettes from the junction zone, said delivery channel having a width sufficient to accommodate a plurality of cigarettes in side-by-side relation; means defining an input channel having a width of several cigarette diameters and adapted to deliver a stack of cigarettes into the junction zone from the trays; a reservoir comprising a conveyor for carrying a stack of cigarettes into or from the junction zone as required; and driving means for continuously driving the conveyor in a direction towards the junction zone at a high speed sufficient to discharge cigarettes from the reservoir at the full rate at which the machine is capable of delivering cigarettes while each tray is being replaced by the next tray, and away from the junction zone at other times at a slower speed so that the reservoir gradually absorbs cigarettes so that it can again discharge cigarettes at the full rate when the next tray is changed.

35. A machine according to claim 34 wherein said means for driving the conveyor comprises reversible drive means for selectively driving said conveyor both towards the junction zone and away from the junction zone and different-ratio transmission means for selectively driving said conveyor at both said high speed and said slower speed respectively.

36. A cigarette tray unloading machine according to claim 34 in which said driving means is adapted to drive the reservoir conveyor at different predetermined speeds in different directions.

37. A cigarette tray unloading machine according to claim 34 in which said input channel, said reservoir, and said delivery channel meet at said junction zone to form a T-shaped junction having two arms extending substantially in line and the third arm substantially at right-angles to the two in-line arms.

38. A cigarette tray unloading machine according to claim 37 in which the two in-line arms of the T-junction are substantially horizontal.

39. A cigarette tray unloading machine according to claim 38 in which the two horizontal arms of the T-junction are the input channel and the reservoir.

40. A cigarette tray unloading machine according to claim 38 in which the input channel, the delivery channel, and the reservoir are all adapted to accommodate stacks of substantially the same height.

41. A cigarette tray unloading machine according to claim 34 including sensing means to sense the level of cigarettes in the junction zone, said driving means being controlled in response to a signal derived from said sensing means.