GB2024758A - Cigarette conveying system with buffer store arrangement - Google Patents

Abstract

Cigarettes are conveyed directly from a making machine to a packing machine by a feed conveyor 10 having an outlet channel 17 leading to a tray filling device 21, and an inlet channel 28 for receiving cigarettes from a tray unloading device 28. A reservoir 14 accommodates short-term differences between supply and demand. In normal operation cigarettes pass along the conveyor 10 and down the chute 13 to the packer. Should normal running be upset so that the reservoir 14 becomes nearly full, cigarettes are fed to conveyor 20 and at least one tray is completely filled, empty trays being accommodated on a reversible tray conveyor 22. Should the reservoir 14 become nearly empty, at least one filled tray, accommodated on reversible conveyor 24, is emptied on to conveyor 28 for feeding back to the conveyor 10 and hence the packer. <IMAGE>

Description

SPECIFICATION Cigarette conveying system This invention is concerned with conveying systems and methods for use in conveying cigarettes between cigarette making machines and cigarette packing machines.

According to one aspect of this invention, a cigarette system comprises a feed conveyor for conveying a stream of cigarettes directly from at least one cigarette maker to at least one cigarette packer; a first transfer conveyor for conveying cigarettes from the feed conveyor to a tray handling device; a second transfer conveyor for conveying cigarettes from the tray handling device to the feed conveyor; a reversible reservoir for accommodating short-tern differences between the cigarette flow rates at a junction including the feed conveyor; the tray handling device comprising means for accommodating a number of full trays, means for accommodating a number of empty trays, means for filling trays with cigarettes received from the first transfer conveyor, means for feeding cigarettes from full trays to the second transfer conveyor; and including a control circuit arranged to respond to the condition of the reservoir whereby, when the reservoir reaches a first predetermined condition (a nearly full condition), the tray handling device is arranged to fill completely at least one empty tray with cigarettes received from the first transfer conveyor, and when the reservoir reaches a second predetermined condition (a nearly empty condition), the tray handling device is arranged to deliver the entire contents of at least one full tray to the second transfer conveyor.

According to another aspect of this invention, a tray handling device (especially but not necessarily for use in accordance with the first aspect of this invention) comprises a horizontal delivery conveyor (e.g. part of the first transfer conveyor) for conveying a stack-like stream of cigarettes for delivery to a tray at a tray-filling station; a first reversible tray conveyor arranged to carry to the tray filling station during tray filling operations a succession of empty trays passing backwards in a direction transverse to and below the delivery conveyor, and to carry away in a reverse direction empty trays during trayunloading operations; means for lifting the tray at the tray-filling station to align the bottom of the tray with the delivery conveyor; means for p unging successive portions of the stack on said delivery conveyor into the tray while the tray is indexed downwards; means defining a tray standby position beyond the tray filling station, to which each full tray is carried by the first tray conveyor, or bv an additional intermediate tray conveyor; means for moving (e.g. lifting) a full tray from the stand-by position and for inverting the tray over a discharge conveyor which conveys a stack of cigarettes from the full tray when required; and a second reversible tray conveyor (which may be a continuation of the first tray conveyor) arranged to carry full trays from the stand-by position while a sequence of tray filling operations is being carried out, and to convey a succession of full trays, in the reverse direction, to the stand-by position while tray unloading operations are being carried out.

The tray filling position and stand-by position may for convenience be spaced apart by a distance greater than that between adjacent trays on each tray conveyor. In that case an intermediate tray conveyor may be used, its speed being appropriately greater than that of the other tray conveyors to provide regular indexing of the trays along the tray conveyers; that would allow more clearance for swinging the full tray to an inverted position, assuming that the tray is moved only in an upward direction before being inverted. As an alternative, however, means may be provided for moving the tray horizontally off the tray conveyor before it is swung to an inverted position, such means being already well known per se; in that case the trays on the tray conveyors can be at uniform intervals and it is possible to use a single tray conveyor for both full and empty trays.

Since the empty trays move backwards towards the tray filling station (by which we mean that the open fronts of the empty trays face away from the tray filling station) the mechanism for plunging the cigarettes into the tray at the filling station can conveniently be located outside the space between the tray filling station and the stand-by position.

When this tray handling device is used in connection with the first aspect of this invention, the feed conveyor preferably extends transversely over the tray conveyor or conveyors. The first transfer conveyor preferably includes two, twisted chutes and a horizontal conveyor (e.g. as described below with reference to the accompanying drawing) so as to displace the cigarette stream from the vertical plane of the feed conveyor and into the plane of the horizontal delivery conveyor of the tray handling device, while at the same time reversing the orientation of the cigarettes. The discharge conveyor can then lie in the vertical plane of the feed conveyor, so that the cigarettes can be fed straight up from it into the feed conveyor.

Other aspects of this invention will be understood from the following description relating to one specific example embodying the various aspects of this invention.

The accompanying diagrammatic drawing is a perspective view of a system according to this invention. The system includes a feed conveyor 10 which is arranged to receive a stack-like stream of cigarettes from a cigarette making machine, e.g. via anielevator of the type described in our British Patent Specification No. 1,453,191 or application No. 52473/ 76 (or corresponding German Offenlegungsschrift No. 2,755,599). As shown diagrammatically by a cigarette 11, the cigarettes lie in the feed conveyor 10 with their filters closest to the viewer. At a junction 12, the cigarettes can pass down a chute 13 leading to a cigarette packing machine (not shown). A reversible reservoir 14 accommodates short-term differences between the flows of cigarettes to and from the junction 12, e.g. in the manner described basically in our British Patent Specification No.

1,299,174, though the reservoir in this instance need not extend along a helix since there is no need for a large capacity; various details from that specification and from the Molins OSCAR system may be used in carrying out the present invention.

The end of the stack of cigarettes in the reservoir 14 is defined by a movable end wall 15 which is shown at a position C representing the nearly full condition of the reservoir. Position D represents the full condition, while positions A and B represent respectively the empty condition and the nearly empty condition.

When the wall 15 reaches position C, the section of the feed conveyor 10 downstream of a junction 16 is stopped, and cigarettes pass instead down a twisted chute 17to a horizontal conveyor 18, then down a furthertwisted chute 19 to a horizontal delivery conveyor 20. During their passage through the chutes 17 and 19, the cigarettes are turned through 1 30e so that their filters on the conveyor 20 face away from the viewer. Successive portions of the cigarette stream are then plunged from the conveyor 20 into a tray at a tray filling station 21. The tray filling station includes means for indexing the tray downwards, the arrangement being, for example, as described in our U.S.Patent specification No.4,073,374 Itwill be understood thatthe conveyors 18 and 20 are the chutes 17 and 19 together form the first transfer conveyor according to this invention.

During tray filling operations, a first reversible tray conveyor 22 carries a succession ofemptytrays 23 backwards towards the tray filling station 21. As long as the reservoirwall 15 remains at position C (which will happen ifthe packing machine stops altogether), the tray filling mechanism will fill successive trays and deliver the filled trays onto a second tray conveyor 24 which, at such times, will move stepwise in the same direction as the conveyor 22. Each full tray, on leaving the filling station 21, arrives directly at a stand-by position occupied by tray 25 in the drawing.

When, for example, the packing machine resumes operation so asto draw cigarettes from the reservoir 14 and thus move the wall 15 towards the junction 12, the tray filling operation automatically stops; however, this does not occur until the tray at the filling station 21 has been completelyfilled. The last-filled tray then comes to rest at the stand-by position 25 in readiness to deliver cigarettes back to the feed conveyor 10 when necessary.

When demand from the junction 12 (by the packer) exceeds supply, the wall 15 of the reservoir moves towards the junction 12 and eventually reaches position B, whereupon a tray unloading operation commences. This operation involves lifting the full tray from the stand-by position (at 25) to a position clear ofthe other full trays 26 on the conveyor 24 and then rotating the tray about an axis transverse to the conveyor 24, in a clockwise direction, to invert the tray over a horizontal discharge conveyor 28. This conveyor then carries a stack-like stream of ciga rettes from the inverted tray (e.g. in the manner described in our British patent specification No.

1,191,342or1,284,873 or 1,339,886 or 1,461,774) and then via an elevator 29 to a junction 30. From the junction 30 the cigarette stream proceeds to the junction 12.

Any well known mechanism (e.g. one involving a chain) can be used to lift and invert the full trays. For example, in that respect and in various other respects the tray unloading part may correspond to the Molins Mark 3 or Mark 4 tray unloader.

It will be understood that the conveyor 28 and elevator 29 form the second transfer conveyor according to this invention.

As long as the reservoir wall 15 remains at position B, a succession offull trays 26 will be unloaded in the same manner, being fed backto the stand-by position 25 by the conveyor 24 operating in reverse. Successive empty trays 23 are received by the conveyor 22, which is driven stepwise in reverse for that purpose.

Thetray conveyors 22, 24 can respectively hold a number of empty and full trays 23 and 26 respectively, e.g. up to 8 each. However, if tray filling or tray unloading continues for a significant time, further empty or full trays (as the case may be) can be delivered either manually or automatically to the appropriate tray conveyor. The drawing shows, in ghost outline, a trolley 31 in a position ready to deliver a batch of empty trays onto the conveyor 22.

Asimilar trolley 32 is shown standing adjacent to the tray conveyor 24; this trolley will serve to supply full trays to the conveyor 24 when needed. Each trolley 31,32 may include a numberofvertical walls forming separate compartments for the respective trays; this could ensure in particular that cigarettes in the full trays are prevented from falling out.

Alternatively, the trolleys 31, 32 may be wheeled to positions adjacent to the ends of the conveyors 22 and 24. In that case each trolley 31,32 will be equipped with a tray conveyor which may be driven by a shaft which connects with a drive in the tray handling machine when the trolley is in the correct operating position.

The twisted chutes 17 and 19 are provided because the cigarette orientation in the trays is opposite to that in the feed conveyor 10. This is because the cigarette orientation is changed when each full tray 26 is inverted over the discharge conveyor 28.

As an alternative, the invention of each full tray 26 may take place by swinging about an axis parallel to the cigarettes, e.g. as described in our British patent application No. 50439/76 (or corresponding German Offenlegungsschrift No. 2,753,350). In that case the chutes 17 and 19 would be twisted in opposite directions so that the final orientation of the cigarettes after passage through them is unaltered.

The twisted chutes may be as described in our British patent specification No. 1,430,061.

A conveyor system according to this invention may be used where the making and packing speeds are slightly different. In that case, during normal running, either tray filling or tray unloading operations (as the case may be) will occur atapproximately regular intervals. For example, if the making speed exceedsthe packing speed than an emptytraywill be filled at approximately regular intervals with excess cigarettes which may then be delivered, by means of the trolleys, to a maker/packer combination which has a continuous deficit of cigarettes.

During each tray filling operation, assuming that the packer continues to run, the reservoir wall 15 will move towards the junction 12. Preferably the reservoir 14 is of such capacity that the wall 15 reaches a position approximately midway between positions B and C (or at least well short of position B) when the tray filling operation is complete.

If the packer remains inoperative during a succession of tray filling operations, the reservoir wall 15 will move from position C and towards the position D during tray changes. Similarly, if the maker is inoperative during tray unloading operations, the wall 15 will move towards position A during tray changing. Positions B and C therefore need to be sufficiently far from positions A and D for that purpose.

The arrival of the wall 15 at position B or C can be detected by means of a photoelectric device or a position transducer or by means of a cam-operated switch (as in OSCAR), the cam being driven via a reduction gear from the motor driving the conveyor forming the floor of the reservoir 14.

Instead of locating the supply to the packer (i.e.

chute 13) between the reservoir 14 and the junctions 16 and 30 it may be preferably to move it to a position relatively close to the maker (with the reservoir still beyond the junctions 16 and 30).

Reference is directed to our British Patent specification No. 1,404,141 in its entirety. That sp'ecification describes a system having some features in common with the present invention. Various details from it may be used in relation to the present invention.

Claims (18)

1. A cigarette conveying system comprising a feed conveyor for conveying a stream of cigarettes directly from at least one cigarette maker to at least one cigarette packer; a first transfer conveyor for conveying cigarettes from the feed conveyor to a tray handling device; a second transfer conveyor for conveying cigarettes from the tray handling device to the feed conveyor; a reversible reservoirfor accommodating short-term differences between the cigarette flow rates at a junction including the feed conveyor; the tray handling device comprising means for accommodating a number of full trays, means for accommodating a number of empty trays, means for filling trays with cigarettes received from the first transfer conveyor, means for feeding cigarettes from full trays to the second transfer conveyor; and including a control circuit arranged to respond to the condition of the reservoir whereby, when the reservoir reaches a first predetermined condition (e.g. a nearly full condition), the tray handling device is arranged to fill completely at least one empty tray with cigarettes received from the first transfer conveyor, and when the reservoir reaches a second predetermined condition (e.g. a nearly empty condition), the tray handling device is arranged to deliver the entire contents of at least one full tray to the second transfer conveyor.

2. A cigarette conveying system as claimed in claim 1,wherein the first transfer conveyor includes a horizontal delivery conveyor for conveying a stack of cigarettes, and said means for filling trays includes means for plunging successive portions of said stack into a tray and indexing the tray to receive successive portions.

3. A cigarette conveying system as claimed in claim 2, wherein the means for feeding cigarettes to the second transfer conveyor includes means for inverting trays over a discharge conveyor which conveys a stack of cigarettes away from the tray.

4. A cigarette conveying system as claimed in claim 2 or claim 3, wherein the tray handling device includes a first reversible tray conveyor arranged to carry to a tray filling station (during tray filling operations) a succession of empty trays passing backwards in a direction transverse to and below the delivery conveyor, and to carry away empty trays in a reverse direction (during tray unloading operations).

5. A cigarette conveying system as claimed in claim 4, including means defining a tray stand-by position beyond the tray filling station, to which each full tray is carried after being filled.

6. A cigarette conveying system as claimed in claim 5, wherein said first tray conveyor moves full trays to said stand-by position.

7. A cigarette conveying system as claimed in claim 5, wherein an additional intermediate tray conveyor is provided to move full trays to said stand-by position.

8. A cigarette conveying system as claimed in any of claims 5,6 and 7, including a second reversible tray conveyor arranged to carry full trays from said stand-by position during a sequence of tray filling operations, and to convey a succession of full trays, in the reverse direction, to the stand-by position during a sequence of tray unloading operations.

9. A cigarette conveying system as claimed in claim 8, wherein said second tray conveyor is a continuation of said first tray conveyor.

10. A cigarette conveying system as claimed in any of claims 5 to 9, wherein the tray filling station and stand-by position are spaced apart by a distance greater than that between adjacent trays on the first tray conveyor.

11. A cigarette conveying system as claimed in any preceding claim, wherein the first transfer conveyor includes means for twisting cigarettes through 180 .

12. A cigarette conveying system as claimed in claim 11, wherein the first transfer conveyor includes a section for conveying cigarettes sideways in a direction away from said feed conveyor.

13. A cigarette conveying system as claimed in any preceding claim, wherein the second transfer conveyor and said feed conveyor lie in a substantial vertical plane.

14. A cigarette conveying system including a tray handling device for conveying a stack of cigarettes for delivery to a tray at a tray filling station; a first reversible tray conveyor arranged to carry to the filling station during tray filling operations a succession of empty trays passing backwards in a direction transverse to and below the delivery conveyor, and to carry away in a reverse direction empty trays during tray unloading operations; means for lifting the tray at the tray filling station to align the bottom of the tray with the delivery conveyor; means for plunging successive portions of the stack on said delivery conveyor into the tray while the tray is indexed downwards; means defining a tray stand-by position beyond the tray filling station, to which each full tray is carried after filling; means for moving a full-tray from the stand-by position and for inverting the tray over a discharge conveyor which conveys a stack of cigarettes from the full tray when required; and a second reversible tray conveyor arranged to carry full trays from the stand-by position during a sequence of tray filling operations, and to convey a succession of full trays, in the reverse direction, to the stand-by position during a sequence of tray unloading operations.

15. A cigarette conveying system as claimed in claim 14, wherein each full tray is carried to the stand-by position by said first tray conveyor.

16. A cigarette conveying system as claimed in claim 14, wherein each full tray is carried to said stand-by position by an intermediate tray conveyor.

17. A cigarette conveying system as claimed in any of claims 14, 15 and 16, wherein said second reversible tray conveyor is a continuation of said first tray conveyor.

18. A cigarette conveying system, substantially as herein described with particular reference to the accompanying drawing.