[0001] The present invention relates to a tool and a method for handling hollow filter components,
which is particularly useful in conventional filter combiners.
[0002] During manufacturing of aerosol generating articles the tobacco rod and the filter
component are assembled in so-called combiners. These combiners comprise tools for
handling and transporting the individual components from hopper drums to the combiner
positions. The components to be combined are usually cylindrically formed elements.
These cylindrical components are conventionally pushed along the transport route via
handling tools which engage centrally with the circular end faces of the cylindrical
components.
[0003] Filter articles used in electronic vaping devices may comprise hollow acetate tubes
(HAT) or fine hollow acetate tubes (FHAT). Such hollow acetate tubes are cylindrical
components which are made from cellulose acetate and which are provided with centrally
arranged axial holes. The dimensions of the hollow acetate tubes such as their outer
diameter or the diameter of the hole vary and can be designed according to the demands
of the respective products.
[0004] Due to their central hole it is difficult to handle hollow acetate tubes with the
centrally engaging pushing means of conventional combiners in a reliable way.
[0005] According to a first aspect of the invention there is provided a tool for engaging
a hollow filter element used in manufacture of aerosol generating articles, comprising
a conveyor bracket for engagement with the hollow filter element,
the conveyor bracket comprising one or more lateral fingers,
wherein each lateral finger contacts an peripheral end face of the hollow filter element.
[0006] During manufacture of aerosol generating articles there may be a need to combine
a plurality of individual components like filter elements or plugs of aerosol forming
substrate within a wrapping material. These components are typically conveyed in a
continuous product stream towards a combining apparatus, where the components are
aligned in a desired order and may be wrapped with suitable wrapping material.
[0007] The tool of the present invention is configured such that the conveyor bracket contacts
the filter element at a peripheral wall region of the end surface of the filter element.
To this end, the conveyor bracket comprises one or more lateral fingers, which contact
the end face of the hollow filter at any time during the pushing action. Thus, the
tool may allow to process hollow filter elements in a more reliable way, independent
of the dimensions of the hollow filter element. This increases flexibility and working
speed in particular during development of new filter elements used in today's aerosol
generating articles.
[0008] The tool may be used for axially pushing the hollow filter element. To this end,
the lateral finger engages with a peripheral portion of the axial end surface of the
hollow filter element. The tool may generally be provided in the form of a rotating
disc, where one or more conveyor brackets are provided at the circumferential periphery
of the disc. The lateral finger pushes the hollow filter element along the conveying
path defined by the outer circumference of the rotating disc and a suitable guiding
means.
[0009] The tool of the present invention is generally suitable for handling any type of
cylindrical filter elements. However, due to the particular configuration of the conveyor
bracket, the tool of the present invention may be particular suitable for handling
hollow filter elements. These hollow filter elements may include hollow acetate tubes,
FHATs or hollow tubes made from carton or paper.
[0010] As used herein, the term "lateral finger" is used to describe a finger of the conveyor
bracket which is configured to contact a lateral portion of a peripheral end face
of the hollow filter element.
[0011] The lateral fingers may have any suitable form that allows the conveyor bracket to
engage with the peripheral end face of a hollow filter element. The lateral finger
may be provided in the form of a triangular element that extends radially from the
conveyor bracket. The surface of the lateral finger that contacts the hollow filter
element during the pushing action may be arranged in radial direction of the disc-shaped
tool, such that this surface is aligned parallel to the end surface of the hollow
filter element. In this way a well-defined contact area is established between the
lateral finger of the conveyor bracket and the hollow filter element.
[0012] The outer diameter of conventionally used hollow filter elements may range between
2 millimeters and 10 millimeters, and may range between 4 millimeters and 8 millimeters.
Depending on their application and the material used, the inner diameter of the hollow
filter elements may be only about 0.5 millimeters smaller than the outer diameter
of the hollow filter element. Such hollow filter elements would then have a remaining
wall thickness of only 0.25 millimeters.
[0013] In order to reliably engage with a portion of the wall of the peripheral end face
of a hollow filter element, the lateral finger needs to be provided at a height that
corresponds to the outer dimensions of such hollow filter element.
[0014] In embodiments where only a single lateral finger is employed, this single lateral
finger may be provided directly at the bottom or at the top of the conveying path,
such as to engage with a lower or with an upper portion of the wall of the peripheral
end face of the hollow filter element.
[0015] The length of the lateral finger may extend to between 50 to 100 percent of the width
of the conveying path. For typical diameters of the hollow filter elements the length
of the finger may amount to between 2 millimeters and 10 millimeters.
[0016] The height of the lateral finger may extend up to 100 percent of the height of the
conveying path. The height of the conveying path corresponds to the diameter of the
hollow filter elements to be transported and may therefore amount to up to 8 millimeters.
As the lateral fingers need to make contact only to one contact area, namely a lower
portion or an upper portion of the wall of the peripheral end face of the hollow filter
element, it is sufficient for the height of the lateral fingers to correspond to the
wall thickness of the hollow filter element. Thus, the height of the lateral finger
may range between 0.25 millimeters and 2 millimeters.
[0017] In embodiments where two lateral fingers are employed, the lateral fingers may be
provided at the bottom and at the top of the conveying path. The separation distance
between the two lateral fingers may amount to the inner diameter of the hollow filter
element. The separation distance between the two lateral fingers may amount between
2 millimeters and 7 millimeters and to between 2 millimeters and 4 millimeters.
[0018] In embodiments where the tool is provided in the form of a rotating disc the lateral
fingers may be provided at the periphery of separate co-axial discs. In order to adjust
the distance between the fingers, spacers of the desired thickness may be provided
between the co-axial discs.
[0019] In embodiments one or more additional fingers may be provided between the lateral
fingers. By using additional lateral fingers the tool may be used with hollow filter
elements of differing sizes without the need to adapt the tool each time a different
sized hollow filter element is to be processed.
[0020] In a further aspect the present invention is directed to a conveyor system used in
manufacture of filter elements for aerosol generating articles. The conveyor system
comprises the aforementioned tool and a conveyor device for conveying hollow filter
elements from an upstream device, for example a cutting drum, towards the tool. The
conveyor device comprises a laterally arranged transport band which frictionally engages
with the external surface of the hollow filter element.
[0021] Hollow filter elements have less structural rigidity than conventional filter elements
and are therefore more sensitive to deformation and damage by conventionally used
conveying chains. In this regard, the belt-based conveying device may be advantageously
used to transport the filter elements towards the tool.
[0022] The belt conveying device may comprise a single endless belt that is running over
two guiding wheels provided at the upstream and a downstream end of the transport
path. At the opposite side of the transport path a guiding rail may be provided. The
hollow filter element may smoothly be engaged between the belt and the guiding rail,
and may be conveyed along the transport path towards the tool. In order to reduce
friction between the hollow filter element and the guiding rail, the surface of the
guiding rail may be polished or may be provided with a low friction coating.
[0023] The guiding rail may be laterally adjustable such that the overall contact pressure
by which the hollow filter element is clamped between the guiding rail and the belt
may be controlled.
[0024] The belt conveying device may also employ two endless belts which are provided at
either side of the transport path. In such configuration nearly no friction is generated
between the hollow filter elements and the transport elements. Accordingly in this
embodiment the risk of deformation or damage of the hollow filter elements is reduced.
[0025] The belt may be made of any material that is typically used in industrie for such
purposes. In particular, the belt may be made from kevlar, fiber glass, fiber glass
coated with rubber, or from metal coated with rubber.
[0026] In a further aspect the present invention is directed to a method for handling hollow
filter elements in the manufacture of aerosol generating articles. The method comprises
the steps of providing a conveyor tool with a conveyor bracket comprising one or more
lateral fingers, and engaging the hollow filter elements by contacting the lateral
fingers of the conveyor bracket with a peripheral end face of the hollow filter element.
[0027] The method may further include the steps of conveying hollow filter elements from
a cutting drum towards the conveyor tool, wherein the conveyor device comprises a
laterally arranged transport band which frictionally engages with the external surface
of the hollow filter element.
[0028] Features described in relation to one aspect may equally be applied to other aspects
of the invention.
[0029] The invention will be further described, by way of example only, with reference to
the accompanying drawings in which:
Fig. 1 shows a hollow filter element and its contact zones;
Fig. 2 shows an embodiment of the tool of the present invention without (Fig. 2a)
and with (Fig. 2b) a hollow filter element;
Fig. 3 shows an embodiment including a conveyor system with a laterally arranged transport
band;
[0030] In Fig. 1 a typical hollow filter element 10 is depicted. The hollow filter element
1 is a cylindrical or tubular element that may be formed from cellulose acetate. The
hollow filter element 1 has a length of about 15 millimeters, an outer diameter of
about 8 millimeters and an inner diameter of about 5 millimeters.
[0031] In existing combiners used in manufacture of aerosol generating systems, conventional
filter elements are conveyed along a given conveying path by handling tools which
comprise centrally arranged extensions which push the filter elements at the center
of an end face of the cylindrical filter elements. These systems are not suitable
for handling hollow filter elements as depicted in Fig. 1, because these filter elements
exhibit a centrally arranged axial hole, which is located at the intended engagement
zone of conventional handling systems.
[0032] The present invention is directed to a tool 20 comprising a conveyor bracket 22 that
has at least one lateral finger 24 which contacts the hollow filter element 10 at
lateral contact zones 12 as depicted by the shaded areas in Fig. 1. The contact zones
12 are those wall portions of the peripheral end face 14 of the hollow filter element
10 which extend below or above the centrally arranged axial hole 16 of the filter
element.
[0033] Fig. 2 shows a section of a tool 20 according to the present invention. The tool
20 is generally disk-shaped and has a plurality of conveyor brackets 22 located at
its peripheral circumference. One of the conveyor brackets 22 is shown in Fig. 2.
The conveyor bracket 22 comprises two lateral fingers 24. The lateral fingers 24 have
a triangular form, wherein the side surface 26 that in use of the tool 20 engages
with the filter elements 10, extends radially from the peripheral circumference of
the tool 20. The two lateral fingers 24 are separated from each other in vertical
direction and are each provided to engage with the lower and the upper contact area
12 of a hollow filter element 10. The conveyor bracket 22 pushes the hollow filter
elements 10 along a conveyor path 27, formed by the outer circumference of the tool
10 and a guiding rail 28.
[0034] The tool 20 depicted in Fig. 2 may be used in combination with a conveyor device
30 as shown in Fig. 3. This conveyor device 30 receives the hollow filter elements
10 from a cutting drum (not shown) and transports the hollow filter elements 10 along
a transport path 32 to the tool 20. The conveyor device 30 comprises an endless transport
band 34 that is provided on one side of the transport path 32. The endless transport
band 34 is provided on one side of the transport path 32. The endless transport band
34 is guided over two end wheels 36 that are provided at the upstream and downstream
ends of the transport path 32. A further guide rail 38 is provided on the opposite
side of the transport path 32. The transport band 34 frictionally engages with the
hollow filter elements 10 and conveys the hollow filter elements 10 along the transport
path 32 from the cutting drum to the tool 20.
[0035] The exemplary embodiments described above illustrate but are not limiting. In view
of the above discussed exemplary embodiments, other embodiments consistent with the
above exemplary embodiments will now be apparent to one of ordinary skill in the art.
1. A tool for engaging a hollow filter element used in manufacture of aerosol generating
articles, comprising
a conveyor bracket for engagement with the hollow filter element,
the conveyor bracket comprising one or more lateral fingers,
wherein each lateral finger contacts a peripheral end face of the hollow filter element.
2. The tool according to claim 1, wherein the conveyor bracket comprises one lateral
finger that is configured to contact a lower or an upper contact zone of a hollow
filter element.
3. The tool according to any one of claims 1 or 2, wherein the conveyor bracket comprises
one lateral finger that is configured to contact the lower and the upper contact zone
of a hollow filter element.
4. The tool according to claim 1, wherein the conveyor bracket comprises two lateral
fingers that are configured to contact a lower and an upper contact zone of a hollow
filter, respectively.
5. The tool according to any one of the preceding claims, which is used for axially pushing
the hollow filter element.
6. The tool according to any one of the preceding claims, wherein the hollow filter element
is a hollow acetate tube, FHAT or carton tube.
7. A conveyor system used in manufacture of filters for aerosol generating articles,
comprising:
a tool in accordance with one of claims 1 to 6, and
a conveyor device for conveying hollow filter elements from a cutting drum towards
the tool,
wherein the conveyor device comprises a laterally arranged transport band which frictionally
engages with the external surface of a hollow filter element.
8. A method for handling a hollow filter element in the manufacture of aerosol generating
articles, comprising the steps of:
providing a tool with a conveyor bracket comprising one or more lateral fingers, and
engaging the hollow filter elements by contacting the lateral fingers of the conveyor
bracket with an peripheral end face of the hollow filter element.
9. The method of claim 8 further comprising:
providing a conveyor device for conveying the hollow filter elements from a cutting
drum towards the tool,
wherein the conveyor device comprises a laterally arranged transport band which frictionally
engages with the external surface of the hollow filter element.