TECHNICAL FIELD

The present invention relates to a duct for transferring a multilayer flow of rod-like elements, to a tobacco industry machine and to a multi-segment tray.

BACKGROUND

In tobacco industry, ducts for transferring multilayer flow of rod-like elements, such as rods made of filtering material or tobacco rods, are used. Such ducts may transfer rods between machines using a powered transporter. Alternatively, they may be configured for a gravitational transfer, without using a powered drive. Ducts without a drive are used for example in machines for unloading containers filled with rod-like elements. In such machines, transferring the multi layer flow of rod-like elements through the ducts is performed gravitationally from the top to the bottom, wherein the rod-like elements are transferred from the filled tray or from a box to the ducts located in an intermediate storage positioned under the container, and next from the ducts of the intermediate storage further to a receiving transporter. The ducts for transferring the multilayer flow of rod-like elements are also used in multi-segment trays, wherein during filling of such tray, the rod- like elements are transferred from a temporary storage to the ducts located in the multi-segment tray.

A tobacco industry machine for unloading containers filled with rod-like elements is known from an European patent application EP 3 305 101 disclosing an intermediate storage located in a machine for unloading containers filled with rod-like elements. The ducts of the storage are made of vertical partitions forming sidewalls of the duct, arranged in parallel with respect to each other, in a single line. The rod-like elements are introduced uniformly from the top of the intermediate storage ducts from the container by means of supporting elements, which displace them downwardly, between the partitions. After introduction of elements up to the very end of the ducts, the elements supporting the rod- like elements are retracted from the ducts through openings in a rear wall, and the multilayer piles of rod-like elements remaining in the duct are received by a receiving transporter, which consecutively displaces a receiving throat under outlets from the ducts of the intermediate storage in order to empty them.

An example of a multi-segment tray for temporary retaining of rod-like elements is known from an European patent EP 2 645 888. The duct in this tray is formed by two sidewalls arranged in parallel with respect to each other in a single line and a rear and bottom wall arranged perpendicularly with respect to the sidewalls. The ducts in the multi-segment trays are used for transferring of the multi-segment flow of rod-like elements in an ordered manner during filling in or emptying of the tray.

The ducts typically used in tobacco industry have sidewalls with straight upper edges. In such ducts, the multilayer flow of elements may be disturbed during transferring the elements from the tray or the box to the intermediate storage, which is caused by rods being stayed on the edges of the neighboring sidewalls, in particular when the length of the elements is greater than the width of the duct, i.e. the distance between the sidewalls. It is caused by the fact that the elements stored in the trays or boxes are often transported from one place of a manufacturing facility to the other, and during such transportation a the arrangement of the rods may change, in particular of the rods in the outer layers, which during transferring from the tray/box to the intermediate storage ducts will not be arranged properly with respect to the sidewalls of the ducts and therefore causing disturbances in the transfer of the flow. It may also happen that rods in the tray/box are arranged in parallel adjacent to the rear wall of the tray/box. Such arrangements of the rods are difficult to be eliminated by an operator and are time consuming, while frequent stoppages of the production process and elements spilling from the machine significantly influence production costs.

Similar problems may occur in other various applications related to filling of a duct with rod-like elements.

The aim of the present invention is to provide a solution, which eliminates the aforementioned deficiencies and provides a seamless filling of the ducts with rod-like elements without a risk of rod-like elements being stayed on the edges of the partitions.

SUMMARY

There is disclosed herein a duct for transferring a multilayer flow of rod-like elements, wherein: the duct is bounded by a first sidewall defining a first inlet edge of the duct and by a second sidewall defining a second inlet edge of the duct; the first sidewall is distanced from the second sidewall by a distance that is smaller or equal to a length of the rod-like element to be transferred through the duct; and the first inlet edge has an edge line with a shape that is different than a shape of an edge line of the second inlet edge.

One of the sidewalls may have an indentation in its inlet edge.

The shape of the edge line of the first inlet edge may be different than the shape of the edge line of the second inlet edge across a distance equal to at least from 20 to 90% of a depth of the duct. The shape of the edge line of the first inlet edge may be different than the shape of the edge line of the second inlet edge in a middle part of this edge.

The first inlet edge and the second inlet edge may have at least two points distanced from each other by a width of the duct and located at the same level at an upper boundary of the inlet edges.

At least one sidewall may have an indentation in its rear edge which is located adjacent to a rear wall of the duct.

The depth of the indentation in the rear edge may be greater than a diameter of the rod- like element to be transferred through the duct.

The rear edge of the sidewall may be at least partially and substantially perpendicularly adjacent to a rear wall of the duct.

At least one inlet edge may have a sinusoidal shape.

The rear edges of the sidewalls may be located on a common plane.

The sidewalls may be arranged in parallel with respect to each other.

The sidewalls may face each other.

A height of the sidewalls may be greater than the depth of the duct.

The sidewalls may be located substantially vertically in the region of the transfer of the rod-like elements.

The sidewalls may be located in a tray for storing the rod-like elements.

The sidewalls may be located in an intermediate storage for changing the level of filling of the tray.

There is also disclosed a tobacco industry machine for unloading containers filled with rod-like elements through at least one duct, wherein said duct is the duct as described herein.

There is also disclosed a multi-segment tray for storing rod-like elements in the segments constituting ducts, wherein at least one segment constitutes the duct as described herein.

BRIEF DESCRIPTION OF FIGURES

The present invention is shown by means of example embodiments in a drawing, in which:

Fig. 1 presents ducts for transferring a multilayer flow of rod- like elements on a machine for unloading filled up containers;

Fig. 2 presents ducts for transferring a multilayer flow of rod-like elements with rod- like elements being arranged improperly; Fig. 3 presents a cross-section view of two neighboring sidewalls;

Fig. 4 presents the sidewall of a duct in a side view;

Fig. 5 presents intermediate storage ducts during introduction of rod-like elements being supported on plates;

Figs. 6a and 6b present further embodiments of edge line of the sidewall;

Fig. 7 presents the duct in a cross-section view;

Fig. 8 present ducts for transferring of the multilayer flow of rod-like elements in the multi-segment tray.

DETAILED DESCRIPTION

The present invention is applicable not only to tobacco industry devices, but also to any other devices comprising a duct which is filled with rod-like elements, for example in devices for manufacturing pencils, glass pipes or straws for beverages.

Fig. 1 presents ducts 1 for transferring multilayer flow of rod-like elements R from a container 2 to an intermediate storage 3. The filled up container 2 is placed above the intermediate storage 3, which is equipped with the ducts 1 for unloading. The rod-like elements R are transferred gravitationally from the container 2 to the ducts 1 from the top through inlets 4. During transferring of the multilayer flow from the container 2 to the ducts 1, the rod-like elements R are supported and lowered into the ducts 1 on supporting plates (Fig. 5), which move from the top to the bottom between sidewalls 5 and 6. The container 2 may have a form of a single-chamber tray, multi-segment tray or a cardboard box for storing rod-like elements R. The rod-like elements R are stored in the container 2 substantially perpendicularly with respect to a rear wall 2a as depicted in Fig. 1. The rod-like elements R are transferred transversally to their longitudinal axis and in parallel with respect to the sidewalls 5 and 6 forming the duct 1. The ducts 1 are configured for transferring, in an ordered manner, the rod like elements R from the container 2 to the intermediate storage 3, from which they are subsequently received by a receiving transporter 7 located under outlets 8 of the ducts 1.

It may happen that some rod-like elements Rw are arranged at an angle with respect to the sidewalls 5, 6. Then during transferring of the elements to the ducts 1, the rod like-elements Rw may collide with an upper edge 9 and/or 10 of the sidewall 5 and/or 6, as depicted in Fig. 2. The sidewalls 5 and 6 are located inside the intermediate storage 3, wherein inner walls of the intermediate storage 3 also constitute sidewalls 6 forming the duct 1 with the neighboring sidewalls 6, wherein the duct is designed for transferring the elements R. Each of the ducts 1 has two sidewalls: the first sidewall 5 and the second sidewall 6 and one common rear wall 1 1 arranged substantially perpendicularly and in abutment to the sidewalls 5, 6. Wherein in another embodiment, there the rear wall 1 1 is not present. Then the moving rod-like elements R in the duct 1 are maintained in a multilayer piles by means of the sidewalls 5 and 6. The sidewalls 5 and 6 are arranges in the intermediate storage 3 in a row, in parallel with respect to each other in a common plane.

The presented solution improves transferring of rod-like elements in case, when a distance W between the two neighboring sidewalls 5 and 6 (i.e. the width of the duct) is smaller or equal to the length of the rod-like elements R transferred in the duct. The arrangement of the sidewalls 5, 6 in such distances from each other prevents rotation of the rod- like elements R located inside the ducts 1 about their shorter transversal axis about an angle greater than 90°, which would cause disturbances in a mass flow.

If a device comprises several neighboring ducts, then it is advantageous that a thickness G of the sidewall is substantially smaller than a diameter of the transferred rod-like element, however it is possible to make sidewalls having greater thickness (then in that case, it is advantageous that their upper surfaces are not flat in order to prevent rod-like elements from remaining on the upper edge).

A height H of the sidewalls 5, 6 depends on a height of the intermediate storage 3, because their upper edges 9 and 10 are located in the region of an inlet 12 to the intermediate storage and their bottom edges 13 are located in a region of an outlet 14 of the intermediate storage 3.

A depth D of the ducts 1 may be arbitrary, however it is advantageous that it is close to the length of the rod-like elements R being transferred in order to facilitate their parallel arrangement in the duct. The depth D may be adjusted depending on the length of the rod-like elements.

Fig. 3 presents an embodiment of the duct 1 formed by the sidewalls 5 and 6. The sidewall 6 comprises an upper edge 10, which has an edge line 18 in a form of a linear segment extending from a rear edge 15 to a front edge 16, arranged substantially on a constant level, preferably perpendicularly to the rear edge 15 and to the front edge 16. The upper edge 9 of the sidewall 5 has an edge line 19 in a form of a nonlinear segment or connected segments located under different angles with respect to each other, located at different levels, extending from a rear edge 17 to the front edge 16. Wherein the edge line 19 of the upper edge 9 has at least two points or segments 2 la, 2 lb located on the same level as the edge line 18 of the neighboring sidewall 6, wherein this level is located at the same height H of the sidewalls 5 and 6, at an upper boundary of the inlet edges. The length of the segment of the edge line 19, on which a middle part is located below the edge line 18 of the neighboring sidewall 6, may be equal from 20% to 90% of the depth D of the duct, preferably from 50% to 90%. The contour of the edge line 19 may be also shaped by an indentation 24 located in a plane of the sidewall 5 in its upper part, adjacent to the upper edge 9.

Moreover, below the upper edge 9, may be located, adjacent to the rear edge 17, a segment of the edge line 19 having a length slightly greater than a diameter of the rod- like element R, forming an indentation 20 in the sidewall 5. The indentation 20 serves for rotating the rod-like elements R, which are transferred from the container 2 to the duct 1 , in parallel to the rear wall 11, as shown in Fig. 2. The indentation 20 may be located in the rear edge of one of the sidewalls 5 or 6 of the duct 1 or may be located in both edges 15 and 17 of the neighboring sidewalls 5, 6 under the condition that the bottom edges 20a of the indentation 20 are located on different levels with respect to each other.

Fig. 4 presents the sidewall 5 in a side view. Two segments 2 la and 2 lb of the upper edge 9 are located on the same level as the edge of the neighboring sidewall 6 (not shown in Fig. 4). The segments 2 la, 2 lb are designed to support the rod-like elements R when the multilayer flow is introduced on supporting plates 22 to the ducts 1.

Fig. 5 presents the supporting plates 22 moving in the ducts 1 between the sidewalls 5 and 6, comprising longitudinal indentations 23 having a width equal or greater than the thickness of the sidewalls 5, 6. If the sidewall 5 had only one point or segment 2 la, 2 lb of the edge line 19 located at the maximal upper level, then the rod- like elements R would be able to enter into the longitudinal indentations 23 causing disturbances in the flow.

Figs. 6a and 6b present sidewalls 5a and 5b in another embodiment. The edge line may have a sinusoidal shape l9a or other arbitrary shape, for example as depicted by a label 19b. An important feature is that a certain segment of the edge 9a, 9b in its middle part is located below the edge line 18 of the neighboring side wall 6. It is preferable, that the edge line 19 of the first upper edge 9 has a different shape than the edge line 18 of the second inlet edge 10 on a distance equal at least from 20 to 90% of the depth D of the duct.

Fig. 7 presents a cross-section of two neighboring sidewalls 5 and 6 along the plane P extending perpendicularly to the side surface of the sidewalls 5 and 6, in a location depicted in Fig. 3.

Due to the fact that the upper edge 9 of the first sidewall 5, constituting the first inlet edge 9 of the duct, differs in shape from the upper edge 10 of the second sidewall 6, constituting the second inlet edge 10 of the duct, and in particular because the edge lines 18, 19 of these edges are located at different levels, the rod-like elements R flowing from the top, which are incorrectly arranged in the mass flow, are rotated after contacting such shaped first inlet edge 9, which increases the probability, that the elements will be arranged in a correct position, which is a position in parallel with respect to the sidewalls 5 and 6. Such motion of the rod-like element R is forced by the shape of the edge line 19 of the sidewall 5 and by the force of gravity and the pressure of rod-like elements incoming from the top. From the solutions known in the state of the art, in which the upper edges of neighboring sidewalls are linear and located on a single level, during the inflow of rod-like elements to the ducts it may happen that the rod-like element, which would be incorrectly positioned in the mass flow (i.e. not parallel with respect to the sidewalls 5 and 6) will stay on two neighboring sidewalls, in particular when the length of this element is greater than the distance between two neighboring sidewalls. The presented solution allows to prevent such situation, because one of the two neighboring sidewalls 5, 6 has a lowered (on at least part of its length, preferably from 20 to 90%) edge 9, and thereby the distance L2 between the two neighboring upper edges 9 and 10 is greater while at the same time the distance W between the two neighboring sidewalls 5 and 6 is maintained, which is smaller or equal to the length Ll of the rod- like element R.

Fig. 8 presents a multi-segment tray 30 with ducts G for transferring the multilayer flow of rod-like elements R, wherein the ducts are formed between partitions constituting sidewalls 5’, 6’. During filling in of the multi-segment trays 30 with rod-like elements, the same problem may occur as in case of filing in the intermediate storage. During filling of the tray 30 the rod- like elements moving from the intermediate storage (presented in Fig. 8) may be positioned incorrectly, and thereby causing their stay on the upper edges of the sidewalls and ducts, and thereby causing disturbances in the flow. In order to eliminate this problem, in the ducts there are sidewalls 5’, 6’ having different shape of an edge line 18’, 19’. The sidewalls 5’, 6’ are arranged alternately inside the tray 30, wherein the extreme sidewalls 6’ are walls having linear edge line 18’. Moreover the tray 30 may also have indentations 20’ in the rear edge 15’, 17’ of one of the sidewalls 5’, 6’ of the duct G.