APPARATUS AND METHOD FOR FILLING A HOLLOW CIRCULAR-SECTION SLEEVE WITH A PRODUCT

Abstract

A pre-formed cone filling apparatus (100) is disclosed for filling paper cones (130) with a ground product such as tobacco or another leaf- or plant-based product such as cannabis The apparatus 100 has individual cone holders (110) mounted vertically on the circumference of a horizontally-oriented rotating wheel (120). The cone holders move in pairs between a number of processing stations which are located around the circumference of the wheel (120). The processing stations include a loading station (200) for loading an individual cone (130) into each cone holder (110), a seating station (300) to ensure the cones (130) are correctly seated in the holders (110) and correctly shaped, a filling station (500) for filling a cone with the product, and a closing station (600) for closing the open end of the filled cone. The filling station also has primary and secondary tamping pins for controlling the product density during and after filling.

Description

TECHNICAL FIELD

The invention relates to an apparatus and a method for filling a hollow circular-section sleeve, such as a paper cylinder or cone, with a product such as tobacco or another leaf- or plant-based product such as cannabis. Typically, the product will be in a ground, fibrous or loose form and the sleeve will have one end closed or partially-closed (e.g. by means of a filter or crutch) and the other end open prior to filling.

BACKGROUND

While hand-rolling of cigarettes etc. is of course widely known, the invention relates to filling pre-formed cylinders or cones by machine. Such machines are known. In one machine, the cone is over-filled with product while the cone is being vibrated, so the weight and density of the product are determined by the volume of the cone and by how much the product settles over time as it is vibrated before the feed is stopped. The cone continues to vibrate after the filling has stopped to increase the density further, and to create a gap at the top for the closure twist. In another machine, the product is fed into an intermediate container before being added to the cone, but there is a risk that not all the product is successfully transferred and there is a possibility of wastage.

All of the currently-available machines suffer from disadvantages including poor accuracy of dose, inconsistent and varying levels of compaction/density, waste and poor speed of process. There is therefore a need for an improved pre-formed cone/cylinder filling machine.

SUMMARY OF THE INVENTION

In accordance with a first aspect, the invention provides an apparatus for filling a hollow circular-section sleeve with a product, wherein the sleeve has an open end and a closed or partially-closed end, the apparatus comprising a plurality of sleeve holders each for receiving a sleeve, each holder being arranged on a base which is movable between a plurality of processing stations, the processing stations including: a loading station for loading a sleeve into a sleeve holder, a filling station for filling a sleeve with the product, and a closing station for closing the open end of the filled sleeve.

In a preferred embodiment, the plurality of holders are mounted around the circumference of a rotatable base and the plurality of processing stations are arranged circumferentially around the base. The base may have the form of a wheel.

The holders may be processed singly at each station or may be processed simultaneously in pairs or in a larger number. In order that the sleeves can be filled by gravity, it is preferred that each holder is arranged such that the sleeve is substantially vertical with the open end uppermost.

In a preferred embodiment, the loading station includes a magazine for storing a plurality of stacked sleeves. The pre-formed sleeves are stored ready for loading singly into a sleeve holder at the loading station.

In a preferred embodiment, the filling station is configured to supply a predetermined amount of product to the sleeve. The predetermined amount may be measured by any suitable means, including weighing, volume measurement, or another system such as the length of time for supplying the product. In a preferred embodiment, an auger is employed to measure the predetermined amount, e.g. by the number of turns of the auger screw. A downstream weighing device, discussed below, may provide a feedback signal to the filling station to adjust the predetermined amount.

Once the predetermined amount of product has been measured, it is supplied by the filling station to the sleeve. This may simply be via a pipe or chute. Preferably the filling station includes a vibrating feed channel/tube configured to supply the predetermined amount of product to the sleeve.

In a particularly preferred embodiment, the filling station includes a primary tamping device (such as a rod or pin) configured to tamp the product during the supply of the predetermined amount of product to the sleeve. The feed channel/tube preferably includes an aperture for the primary tamping device to allow access to the product in the sleeve during supply. The purpose of the primary tamping device is to prevent blockages or “bridging” during the filling of the sleeve. In a preferred process, the feed tube starts to vibrate, and after a set time the tamping pin lowers to a set depth, pushing the product down, and then is immediately raised so as not to block the filling process. This may be repeated at different time intervals during the fill, at different depths. The primary tamping device achieves a consistency of density not possible with prior art processes, as it can be used to control density of the product at all levels of the sleeve, including near the closed end.

The filling station preferably also includes a secondary tamping device (such as a rod or pin) configured to tamp the product after the supply of the predetermined amount of product to the sleeve. This is a similar device to the primary tamping device, but it is used to control the final density of the product.

The filling station may also include one or more sensors configured to determine the position of the primary and/or secondary tamping device during tamping. Typically this will be the vertical position of the tamping device. The time at which the tamping device is lowered into the sleeve and/or the duration for which it is lowered may also be controlled.

The filling station may also include one or more hoppers to store the product, which may be provided with a monitoring system to alert when running low, empty or blocked.

The closing station preferably includes a twist mechanism configured to clamp and twist the sleeve end closed. In a preferred embodiment, the twist mechanism comprises a pair of grippers which rotate to twist the end closed. They may also be driven in the vertical axis to adjust the height as the twist is completed. Adjustment in the vertical axis avoids tearing and can be used to accommodate different cone sizes.

The twisting operation may be completed with the sleeve still in the holder. However, in a preferred embodiment, the sleeve is raised up slightly to ensure that each sleeve is at a consistent height for the closing operation. When the sleeve is a cone, due to the angle of the cone, very small differences in cone diameter result in relatively large changes to the height at which the cones sit in the holder.

The processing stations may also include a seating station configured to correctly seat the sleeve in the holder. This station is preferably located between the loading and filling stations. The seating station preferably includes a probe for inserting into the sleeve which is configured to supply air to correctly seat the sleeve in the holder. As an alternative, or in addition, a former may be provided for inserting into the sleeve to shape the cone.

The processing stations may also include a checking station configured to check that the open end of the sleeve is properly open and in the correct position for filling. This station is preferably located between the loading and filling stations, and if present, after the seating station. The checking station may include a sensor for determining the position of the sleeve (e.g. the vertical position of the top edge) and/or imaging means to determine whether the open end is properly open and not partially closed.

As mentioned above, the processing stations may also include a check-weighing station configured to check the weight of the filled sleeve and to generate a signal which is supplied to the filling station to check or adjust the predetermined amount of product. This station is preferably located after the closing station.

The processing stations may also include a discharge station to remove the filled, closed sleeve from the holder. This station is preferably located after the closing station, and if present, after the check-weighing station.

The processing stations may also include a cleaning station for cleaning the empty holder. This station is preferably located after the removal station. The cleaning station preferably comprises an insert which is movable into the empty holder and is configured to supply compressed air to clean the holder.

Once the filled, closed sleeve has been removed and optionally the holder has been cleaned, the holder then returns to the loading station to start the process again.

The essential and preferred/optional operations performed at the various processing stations described above may be combined such that more than one operation is performed at a given station.

In accordance with a second aspect, the invention provides a method of filling a hollow circular-section sleeve with a product, wherein the sleeve has an open end and a closed or partially-closed end, employing an apparatus comprising a plurality of sleeve holders each for receiving a sleeve, each holder being arranged on a base which is movable between a plurality of processing stations, the method comprising the steps of: loading a sleeve into a sleeve holder, filling a sleeve with the product, and closing the open end of the filled sleeve.

The method may also include any of the preferred or optional operations performed by the apparatus described above.

In preferred embodiments of either aspect of the invention, the hollow circular-section sleeve is preferably a cylinder or a cone. More preferably, the hollow circular-section sleeve is a truncated cone. The sleeve, cylinder, cone or truncated cone is preferably formed from paper such as cigarette paper. The sleeve is preferably a pre-rolled truncated paper cone.

The closed or partially-closed end of the sleeve is preferably closed by means of a filter or crutch. “Partially-closed” is intended to mean that the sleeve is sufficiently closed such that it retains the product during the filling process and when filled. The level of partial closure required will therefore depend on the characteristics of the product being filled.

The product may be in a ground, cut, flaked, fibrous or loose form. In a preferred embodiment, the product includes tobacco or another leaf- or plant-based product such as cannabis.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the invention will now be described by way of example only and with reference to the accompanying drawings, in which:

FIG. 1 shows a schematic, perspective view of a pre-formed cone filling apparatus in accordance with the invention;

FIG. 2 shows a cross-section view of a pre-formed cone and cone holder of the apparatus of FIG. 1;

FIG. 3 shows a schematic, perspective view of the loading station of the apparatus of FIG. 1;

FIG. 4 shows a schematic, perspective view of the seating station of the apparatus of FIG. 1;

FIG. 5 shows a schematic, perspective view of the checking station of the apparatus of FIG. 1;

FIG. 6 shows a schematic, perspective rear view of the filling station of the apparatus of FIG. 1;

FIG. 7 shows a schematic, perspective front view of the filling station of the apparatus of FIG. 1;

FIG. 8 shows a schematic, perspective view of the filling station of the apparatus of FIG. 1 showing the primary and secondary tamping pins;

FIG. 9 shows a schematic, perspective view of the closing station of the apparatus of FIG. 1;

FIG. 10 shows a schematic, perspective view of the check-weighing station of the apparatus of FIG. 1; and

FIG. 11 shows a schematic, perspective view of the cleaning station of the apparatus of FIG. 1.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

FIG. 1 shows a schematic, perspective view of a pre-formed cone filling apparatus 100 in accordance with the invention. Individual cone holders 110 are mounted vertically on the circumference of a horizontally-oriented rotating wheel 120. The cone holders move in pairs between a number of processing stations 200, 300, 400 etc. which are located around the circumference of the wheel 120.

FIG. 2 shows a cross-section view of a cone holder 110 with a pre-formed cone 130 in position for filling. Cone 130 is a circular-section truncated cone made from paper. A crutch 140 is pre-fitted to the cone as a partial filter and to prevent the product from falling through the cone during and after the filling process. Cone holder 110 has an internal conical surface 150 corresponding to the profile of the cone 130, in order to provide support to the cone during filling and processing.

The various processing stations will now be discussed in more detail.

FIG. 3 shows a schematic, perspective view of loading station 200. Loading station 200 has a circular, servo-indexed magazine 210 with a number of stack holders 211 which can be loaded with stacks of pre-formed cones 130. An A & B pair of two stacks is located in the release position directly above the empty cone holders 110 which arrive in pairs at the loading station. A feed system within each stack holder 211 separates a single cone 130 from the bottom of the stack and the single cones are dropped into their respective cone holders 110. The feed system comprises a platform on which the stack rests and a grip for holding the second cone up in the stack. When a cone is to be released into the holder below, the platform opens and the lowermost cone falls into the holder. The platform then closes and the grip on the now lowermost cone is released and the stack is allowed to rest on the platform again. The grip is then reapplied to the second cone up in the stack.

When the A&B pair of stack holders 211 in the release position become empty, the magazine 210 is rotated to locate a new, full pair of A & B stack holders in the release position. The empty stack holders 211 are then replenished by feed system 212 which contains larger magazines 213 of cones 130.

FIG. 4 shows a schematic, perspective view of seating station 300. This station ensures the cones 130 are correctly seated in the holders 110 and correctly shaped, ready to be filled with the product. In a first operation, an air probe 310 is inserted into or positioned above each cone to deliver an air blast to ensure that the cone is correctly seated in the holder. In a second operation, a former (not shown) is inserted into each cone to ensure that the cone has the correct shape.

FIG. 5 shows a schematic, perspective view of checking station 400. Sensors underneath cover 410 check that the mouth of the cone 130 is open and that the top edge of the cone is in the correct position.

FIG. 6 shows a schematic, perspective rear view of filling station 500. Two hoppers 510 are provided to contain the product with which the cones are filled. The product is or includes a ground, plant-based product such as cannabis. A hopper monitoring system provides an alert when the level is running low, a hopper is empty or is blocked.

An auger (not shown) inside each hopper is rotated a set number of turns to provide a measured quantity of product to a feed channel 520 below each hopper. Feedback from the check-weigh station discussed below is used to control and adjust the metered quantity of product. Feed channels 520 vibrate to deliver the product to each cone 130 as shown in FIG. 7, which shows a perspective front view of the filling station 500. The tubes only feed the cones when they have been confirmed as present and open at the checking station. Feed channels 520 supply the product to vertical feed pipes 530 which deliver the product into each cone 130. The feed channels and/or feed pipes may be fixed in position or they may be movable such that the feed pipes 530 can be lowered into each cone 130.

The filling station also includes two primary tamping pins 540 which are lowered at one or more predetermined times during the filling operation into the tops of the feed pipes 530 to tamp down the product in the cones 130. This tamping operation prevents blockages or “bridging” during the filling process and also controls the density of the product. The tamping pins 540 are lowered to a set depth and then immediately raised so as to minimise interference with the filling process. The tamping operation may be repeated during the filling process, with the set depth raised appropriately each time.

The filling station preferably also includes a secondary tamping station 550 with two secondary tamping pins 560 which tamp the product after the completion of the filling operation. This is shown in FIG. 8. This is a similar device to the primary tamping device, but it is used to control the final density of the product. The feed channels 520 and feed pipes 530 are absent at this station, and therefore the secondary tamping pins 560 can be inserted directly into the cones 130.

FIG. 9 shows a schematic, perspective view of closing station 600. This station has a pair of servo-driven, pneumatically-operated grippers 610 which rotate to twist the ends of the cones 130 closed. The grippers 610 are servo-driven in the vertical axis (ascending during the twist) to adjust their height as the twist is completed. This provides a high-quality, uniform twist and avoids tearing of the cone paper. Height adjustment also allows different cone sizes to be accommodated. The grippers are also rotated by means of servos, and are opened/closed pneumatically. During this process, the cones remain in the holders but they may be raised slightly to a consistent, predetermined height so that the twist operation is uniform. This may be achieved by a platform underneath the cone which raises the cone. This operation will also release any taper-lock between the cone and the holder.

FIG. 10 shows a schematic, perspective view of check-weighing station 700. The filled, closed cones 130 are rotated to check-weighing station 700 where they are weighed by load cells 710. Dynamic, continuous feedback is provided to the filling station 500 (auger) for continuous checking and if necessary adjustment of the metered quantity of product.

Although not shown in the drawings, a discharge station is provided after the check-weighing station 700. Here, the filled, closed and weighed cones which are within specification are ejected from the cone holders 110 individually and are sent for downstream packaging. Any under- or over-weight cones are rejected automatically. Pneumatic pins are used to remove the cones from the holders.

The final cleaning station 800 is shown in FIG. 11. An air probe 810 is lowered into each empty cone holder 110 to deliver an air blast to ensure that no product or debris remains in the holder so that it is clean for the next filling operation. The holders 110 are then rotated around to the loading station 200 and the process repeats.

Claims

1. Apparatus for filling a hollow circular-section sleeve with a product, wherein the sleeve has an open end and a closed or partially-closed end, the apparatus comprising a plurality of sleeve holders each for receiving a sleeve, each holder being arranged on a base which is movable between a plurality of processing stations, the processing stations including: a loading station for loading the sleeve into a sleeve holder;a filling station including: a feed channel/tube having an aperture and being configured to supply product into the sleeve,a primary tamping pin configured to tamp the product while the product is supplied into the sleeve, by lowering through the aperture during the filling operation and contacting the product, anda secondary tamping pin configured to tamp the product after the product has been supplied into the sleeve; anda closing station for closing the open end of the filled sleeve.

2. The apparatus of claim 1, wherein the plurality of holders are mounted around the circumference of a rotatable base and the plurality of processing stations are arranged circumferentially around the base.

3. The apparatus of claim 1, wherein the loading station includes a magazine for storing a plurality of stacked sleeves.

4. The apparatus of any preceding claim, wherein the filling station is configured to supply a predetermined amount of product to the sleeve.

5. The apparatus of claim 1, wherein the feed channel/tube is configured to vibrate during supply of a predetermined amount of product to the sleeve.

6. (canceled)

7. (canceled)

8. (canceled)

9. The apparatus of claim 1, wherein the filling station includes one or more sensors configured to determine the position of the primary and/or secondary tamping device during tamping.

10. The apparatus of claim 1, wherein the closing station includes a twist mechanism configured to clamp and twist the sleeve end closed.

11. The apparatus of claim 1, wherein the processing stations include a seating station configured to correctly seat the sleeve in the holder.

12. The apparatus of claim 11, wherein the seating station includes a probe for inserting into the sleeve which is configured to supply air to correctly seat the sleeve in the holder.

13. The apparatus of claim 11, wherein the seating station includes a former for inserting into the sleeve to shape the cone.

14. The apparatus of claim 1, wherein the processing stations include a checking station configured to check that the open end of the sleeve is properly open and in the correct position for filling.

15. The apparatus of claim 1, wherein the processing stations include a check-weighing station configured to check the weight of the filled sleeve and to generate a signal which is supplied to the filling station to check or adjust the amount of product.

16. The apparatus of claim 1, wherein the processing stations include a discharge station to remove the filled, closed sleeve from the holder.

17. The apparatus of claim 1, wherein the processing stations include a cleaning station for cleaning the empty holder.

18. (canceled)

19. The apparatus of claim 1, wherein the hollow circular-section sleeve is a cylinder or a cone.

20. The apparatus of claim 19, wherein the hollow circular-section sleeve is a truncated cone.

21. The apparatus of claim 1, wherein the hollow circular-section sleeve is formed from paper.

22. The apparatus of claim 1, wherein the closed or partially-closed end is closed by means of a filter or crutch.

23. The apparatus of claim 1, wherein the product is in a ground, cut, flaked, fibrous or loose form.

24. The apparatus of claim 1, wherein the product includes tobacco or another leaf- or plant-based product such as cannabis.