U.S. patent application number 11/019576 was filed with the patent office on 2006-06-22 for multi-stage heater plates for sealing and shrinking overwrap.
This patent application is currently assigned to Philip Morris USA Inc.. Invention is credited to William J. Rech, Duane C. Wilder.
Application Number | 20060130433 11/019576 |
Document ID | / |
Family ID | 36061561 |
Filed Date | 2006-06-22 |
United States Patent
Application |
20060130433 |
Kind Code |
A1 |
Wilder; Duane C. ; et
al. |
June 22, 2006 |
Multi-stage heater plates for sealing and shrinking overwrap
Abstract
An improved cigarette package has been achieved using multistage
heating plates on the ends of package wrapping. The first stage of
the heating plate preheats the wrapping, the second stage activates
adhesive along edges of the wrapping, the third stage seals the
wrapping and the fourth stage shrinks the wrapping around the
cigarette packs.
Inventors: |
Wilder; Duane C.;
(Chesterfield, VA) ; Rech; William J.;
(Midlothian, VA) |
Correspondence
Address: |
CONNOLLY BOVE LODGE & HUTZ, LLP
P O BOX 2207
WILMINGTON
DE
19899
US
|
Assignee: |
Philip Morris USA Inc.
Richmond
VA
|
Family ID: |
36061561 |
Appl. No.: |
11/019576 |
Filed: |
December 22, 2004 |
Current U.S.
Class: |
53/442 ;
53/557 |
Current CPC
Class: |
B29C 66/1122 20130101;
B29C 66/849 20130101; B29C 66/8242 20130101; B29C 66/80 20130101;
B29C 65/30 20130101; B29C 66/0242 20130101; B29C 66/919 20130101;
B29C 66/43121 20130101; B65B 19/223 20130101; B29C 66/91421
20130101; B29C 66/91645 20130101; B65B 53/02 20130101; B29C 65/18
20130101; B29C 66/83221 20130101; B29C 66/91431 20130101; B65B
51/14 20130101; B29C 66/91231 20130101 |
Class at
Publication: |
053/442 ;
053/557 |
International
Class: |
B65B 53/02 20060101
B65B053/02 |
Claims
1. A heating plate for packaging comprising: a first stage that
comprises a flat surface for contacting wrapping that is folded
around packages; a second stage that comprises first recessed areas
and first non-recessed areas, wherein the first non-recessed areas
comprise four surfaces for contacting the wrappings of packages; a
third stage that comprises second recessed areas and second
non-recessed areas, wherein the second non-recessed areas comprise
two contiguous H-shaped surfaces for contacting the wrappings of
packages; and a fourth stage that comprises third recessed areas
and third non-recessed areas, wherein the non-recessed areas
comprise four trapezoidal shaped surfaces for contacting the
wrappings of packages.
2. The heating plate according to claim 1, wherein heat is supplied
to the heating plate using multiple heating devices.
3. The heating plate according to claim 2, wherein heat is supplied
to the heating plate by at least two independently controlled
heating devices.
4. The heating plate according to claim 3, wherein the heating
devices are maintained at a temperature of between about
140.degree. C. and 170.degree. C.
5. The heating plate according to claim 3, wherein the heating
devices are maintained at a temperature of about 150.degree. C.
6. The heating plate according to claim 2, wherein heat is supplied
to the heating plate using at least four independently controlled
heating devices.
7. The heating plate according to claim 6, wherein two of the
independently controlled heating devices are maintained at a
temperature of between about 140.degree. C. and 160.degree. C. and
two of the independently controlled heating devices are maintained
at a temperature of between about 160.degree. C. and 180.degree.
C.
8. The heating plate according to claim 6, wherein two of the
independently controlled heating devices are located on a portion
of the heating plate directly opposite the first stage and second
stage and are maintained at a temperature of 150.degree. C., and
two of the independently controlled heating devices are located on
a portion of the heating plate directly opposite from the third
stage and fourth stage and are maintained at a temperature of
170.degree. C.
9. The heating plate according to claim 1, wherein the third
recessed areas in the fourth stage have a first recessed portion
and a second recessed portion, wherein the second recessed portion
is recessed further than the first recessed portion and, wherein
the second recessed portion is rectangular shaped.
10. The heating plate according to claim 1, wherein the first stage
preheats wrappings around the packages, the second stage activates
adhesive along edges of wrappings, the third stage seals wrappings
around packages, and the fourth stage shrinks wrappings around
packages.
11. The heating plate according to claim 1, wherein the first
stage, the first non-recessed areas, the second non-recessed areas,
and the third non-recessed areas all lie in the same plane.
12. A heating apparatus for use in cigarette packaging comprising:
a heating area comprising a multiple stage heating plate; a first
reciprocating device that advances a set of cigarette packs
linearly through the heating area and along multiple stages of the
multiple stage heating plate; and a second reciprocating device
that moves the multiple stage heating plate inwardly to contact the
set of cigarette packs and outwardly to allow the set of cigarettes
to be moved through the heating area.
13. A heating apparatus according to claim 12, wherein the set of
cigarette packs contacts multiple areas of the multiple stage
heating plate as the set of cigarette packs is linearly advanced
through the heating area.
14. The heating apparatus according to claim 13, wherein each
occurrence of contact between the set of cigarette packs and the
multiple stage heating plate corresponds to a heating stage.
15. A heating apparatus according to claim 12 further comprising a
loading passage through which sets of packs are advanced into the
heating area.
16. A heating apparatus according to claim 12 wherein the first
reciprocating device comprises a reciprocating arm body, a
pivotable lever arm, and a spring mechanism.
17. A method of sealing and shrinking a wrapping material around
packages comprising: contacting the wrapping material with a first
heating stage to preheat the wrapping material along folded edges;
contacting the wrapping material with a second heating stage to
tack the wrapping material; contacting the wrapping material with a
third heating stage to seal the wrapping material around the
packages; and contacting the wrapping material with a fourth
heating stage to shrink the wrapping material.
18. The method of claim 17 wherein the four heating stages are on
one heating plate.
19. A cigarette pack sealed according to the method of claim
17.
20. A cigarette pack sealed by the apparatus of claim 12.
21. A heating plate for packaging comprising at least two of the
following stages: a first stage for contacting wrapping that is
folded around a package; a second stage that comprises first
recessed areas and first non-recessed areas; a third stage that
comprises second recessed areas and second non-recessed areas; and
a fourth stage that comprises third recessed areas and third
non-recessed areas.
22. The heating plate according to claim 21, wherein the heating
plate comprises at least three of the stages.
23. The heating plate according to claim 21, wherein the heating
plate comprises the first stage, the second stage, the third stage
and the fourth stage.
24. The heating plate according to claim 21, wherein heat is
supplied to the heating plate by at least two independently
controlled heating devices.
25. The heating plate according to claim 24, wherein the heating
devices are maintained at a temperature of between about
140.degree. C. and 170.degree. C.
26. The heating plate according to claim 25, wherein the heating
devices are maintained at a temperature of about 150.degree. C.
27. The heating plate according to claim 21, wherein heat is
supplied to the heating plate using at least four independently
controlled heating devices.
28. The heating plate according to claim 27, wherein two of the
independent heating devices are located on a portion of the heating
plate directly opposite the first stage and second stage and
maintained at a temperature of between about 140.degree. C. and
160.degree. C., and two of the independent heating devices are
located on a portion of the heating plate directly opposite from
the third stage and fourth stage and are maintained at a
temperature of about 160.degree. C. and 180.degree. C.
29. The heating plate according to claim 28, wherein the two
independent heating devices located on the portion of the heating
plate directly opposite the first stage and second stage are
maintained at a temperature of 150.degree. C., and the two
independent heating devices located on the portion of the heating
plate directly opposite the third stage and fourth stage are
maintained at a temperature of 170.degree. C.
30. The heating plate according to claim 21, wherein the first
stage preheats wrapping around a package, the second stage
activates adhesive along edges of the wrapping, the third stage
seals the wrapping around the package, and the fourth stage shrinks
the wrapping around the package.
31. The heating plate according to claim 21, wherein the first
stage, the first non-recessed areas, the second non-recessed areas,
and the third non-recessed areas all lie in the same plane.
32. A method of sealing and shrinking a wrapping material around a
package comprising at least two of the following steps: contacting
the wrapping material with a first heating stage to preheat the
wrapping material along folded edges; contacting the wrapping
material with a second heating stage to tack the wrapping material;
contacting the wrapping material with a third heating stage to seal
the wrapping material around the package; and contacting the
wrapping material with a fourth heating stage to shrink the
wrapping material.
33. The method of claim 32 wherein the four heating stages are on
one heating plate.
34. A cigarette package sealed according to the method of claim
32.
35. A cigarette package sealed by the heating plate of claim
21.
36. A heating plate for packaging comprising at least two of the
following stages: a first stage that preheats wrapping around a
package; a second stage that activates adhesive on the wrapping; a
third stage that seals the wrapping around the package; and a
fourth stage that shrinks the wrapping around the package.
37. The heating plate according to claim 36, wherein the heating
plate comprises at least three of the stages.
38. The heating plate according to claim 36, wherein the heating
plate comprises the first stage, the second stage, the third stage
and the fourth stage.
Description
BACKGROUND OF THE INVENTION
[0001] The disclosed invention relates to a method and apparatus
for manufacturing packages sealed with a wrapper. It is
conventional in the art of packaging, particularly the art of
cigarette packaging, to wrap the final package in shrink wrap film
to maintain freshness and to serve as a tamper seal. Heat is
applied to shrink the film enclosing the cigarette package.
[0002] Conventional packages, such as those used for cigarettes,
comprise an outer container or pack which consists of paper in the
case of "soft" packs, or of a cardboard box in the case of "hard"
packs. The pack is then sealed by covering it with a substantially
airtight material, the overlapping edges of which are bonded or
heat-sealed together. There is a need and desire in the art for a
wrapped package with improved non-melted end-fold seals and overall
film tightness.
[0003] U.S. Pat. No. 4,887,408 to Mattei et al. teaches a
conventional method for sealing the ends of product wrapping. The
package is loaded into a drum with the wrapping covering three
sides of the package in a U-shaped fashion. Heaters contact the
packages on the side facing away from the drum. The heaters bond
the two sides of the wrapping material together to seal the sides
of the package in a sheath-like manner. The ends of the wrapping
material are folded to enclose the packages. Packages are then
conveyed through three heating stations to seal the top and bottom
ends of the packages by fusing the folded wrapping material upon
itself.
[0004] U.S. Pat. No. 4,330,977 to Focke also teaches using heating
elements for sealing packages. Separated heating elements allow
different sealing temperatures to be used.
[0005] U.S. Pat. No. 5,477,661 to Draghetti teaches loading
cigarette packs onto a drum and heating at a low temperature for a
long time to seal packages.
[0006] It is conventional to use heater blocks with an "H" pattern
(such as used by G. D. Societa' per Azioni) and with a rectangular
pattern (such as used by Focke & Co.) for sealing. In these two
designs, the operator must reduce the temperature to avoid melting
the single folds which cannot withstand the high temperatures and
relatively long periods required to heat the multiple folds. The
areas where the folds are five layers thick thereby suffer from
insufficient heating.
[0007] In addition to having wrapping that is insufficiently sealed
or, in the other extreme, melted, the conventional finished product
has wrinkles 80 as show in FIG. 11.
[0008] It has therefore been discovered that current apparatuses
and methods are incapable of producing uniform, unwrinkled packages
with a reliable end fold seal.
[0009] It is therefore an object of the invention to provide a
method and apparatus for manufacturing a wrapper that will improve
end fold sealing and improve the overall appearance of the wrap.
Yet another object of the invention is to manage heat input into
the poly wrap to increase shrinkage, yet preventing melting. It is
also an object of the invention to improve heat input using
multiple separate controllers. The multiple stage heater according
to the present invention achieves these objectives.
SUMMARY OF THE INVENTION
[0010] According to a first embodiment, a package that has been
enveloped in a film is sealed using a multiple stage heater. The
heater of the present invention decouples the sealing into various
stages to provide more uniform heat to package wrapping,
particularly shrink wrapping, while avoiding melting.
[0011] Those skilled in the art will appreciate the above stated
advantages and other advantages and benefits of various embodiments
of the invention upon reading the following detailed description of
the embodiments with reference to the below-listed drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Novel features and advantages of the present invention in
addition to those noted above will be become apparent to persons of
ordinary skill in the art from a reading of the following detailed
description in conjunction with the accompanying drawings wherein
similar reference characters refer to similar parts and in
which:
[0013] FIG. 1 shows a schematic top plan view of a portion of a
cigarette packaging apparatus.
[0014] FIG. 2 shows a side elevational view of the loading passage
and heating area of the cigarette packaging apparatus of FIG. 1
during a first step of operation.
[0015] FIG. 3 shows a side elevational view of the loading passage
and heating area of the cigarette packaging apparatus of FIG. 1
during a second step of operation.
[0016] FIG. 4 shows a front elevational view of a heater block that
contacts the cigarette packs in accordance with a preferred
embodiment of the invention.
[0017] FIG. 5A shows a rear elevational view of the heater block
shown in FIG. 4.
[0018] FIG. 5B shows a rear side elevational view of an alternative
embodiment of a heater block in accordance with the preferred
embodiment of the invention.
[0019] FIG. 6 shows a cross sectional plan view of the heater block
taken along line 6-6 of FIG. 4.
[0020] FIGS. 7-10 show cigarette packs with the areas in phantom
representing the areas contacted by the heater block illustrated in
FIG. 4.
[0021] FIG. 11 shows a cigarette pack of the prior art.
[0022] FIG. 12 shows a cigarette pack with a smooth outer wrapping
according to the invention.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
[0023] Referring with more particularity to the drawings, FIGS.
1-10 illustrate preferred embodiments of the invention. FIG. 1
shows a plan view of a packaging apparatus 10 that could be used to
package articles such as cigarette packs 12 using a pusher or lever
arm 14 to load packs 12 from a loading passage 15 in heating area
32. FIG. 2 shows a profile view of the packaging apparatus 10.
[0024] Packs 12 are wrapped and folded in a conventional manner
(not shown) and loaded into the loading passage 15 according to any
conventional manner known in the art. Wrapping 13, shown in FIG. 12
can be any conventional material including polymer or cellophane,
and may include a metalized surface.
[0025] As shown in FIG. 2, packs 12 are fed through a loading
passage 15 along a guide 18 into heating area 32. The packs are
guided into position in the heating area using guide 18, an
L-shaped stop 17 and lever arm 14. Lever arm 14 may be connected
along a pivotable axis 28 to a reciprocating arm 20 and
automatically positioned using spring member 22. Arm 20 may be
clamped to moveable shaft 26 and connected to a machine 24 to move
back and forth across the loading passage 15. The shaft can be
driven pneumatically, mechanically or by other conventionally known
forces (not shown) or it can be stationary with the arm body being
driven in a conventional manner along the shaft. As shown in FIGS.
2 and 3, the lever arm 14 is aligned to push the packs 12.
[0026] As shown in FIG. 3, the machine moves the arm body by
extending the shaft 26. The lower portion of lever arm 14 rotates
about its axis 28 (shown in phantom) permitting the arm body 20 and
lever arm 14 to pass over the packs 12 in loading passage 15. The
rotation of the lever arm 14 causes a lever arm tab 30 to place
spring member into a stressed or biased condition (shown in
phantom). The arm body 20 reaches a predetermined stopping point
after passing over the packs 12, such that the packs 12 no longer
maintain the lever arm 14 in the pivoted position. The spring
member 22, which was previously placed in a stressed or biased
condition by the influence of lever arm tab 28, returns to its
relaxed state. Thus, the lever arm 14 is pivoted back to its
downward extending position so as to be aligned with the arm body
20 for pushing the packs 12.
[0027] The spring member 22 could be comprised of spring steel or
any shape memory material that can apply sufficient force to press
lever arm tab 30 back into the recessed portion of arm body 20.
Alternatively, spring member 22 could be any conventional mechanism
that would permit the arm tab to extend and would also press the
arm tab 30 back into the recessed portion of arm body 20.
[0028] After reaching the predetermined stopping point, the arm
body 20 travels back to the position shown in FIG. 2, pushing packs
12 through the heating area 32 along surface 33, which may be
grooved. When the lever arm 14 pushes one set of packs 12 from a
first stage of the heating area 32, which overlays the loading
passage 15, to a second stage of the heating area 32, another set
of packs 12 are advanced through the loading passage 15 into
heating area 32. FIGS. 2 and 3 illustrate the invention with lever
arm 14 pushing two packs at a time. It is anticipated, however,
that the apparatus and method could be modified to push any number
of packs without straying from the invention.
[0029] The packs 12 are guided along surface 33 through the heating
area 32 by a hold down bar 34. While in the heating area, packs 12
are contacted by one or a pair of heater plates, such as the heater
plate 36 shown in FIGS. 1-4.
[0030] When the packs 12 are initially pushed up from the loading
passage 15 into the heating area 32, they can remain in that
initial position or stage for any predetermined amount of time. It
is anticipated, however, that the packs 12 will remain at each
stage in the heating area long enough for the arm body to travel
back and forth and slide another set of packs 12 from the first
stage to the second stage.
[0031] Each set of packs 12 being pushed by the lever arm 14 will
in turn push adjacent sets of packs 12 through multiple stages of
the heating plate 36 and onto wheel 38 as shown in FIG. 1. The
heater plates 36 can be connected to motors 37 which move the
heater plates 36 in position to contact the packs 12 when the packs
12 are stationary and move the heater plates 36 away from packs 12
as the packs 12 are pushed through heating area 32. Like shaft 26
and machine 24, reciprocating motor 37 can be any conventional
device for moving such as an arm, shaft or piston and may be
powered by manual, pneumatic, electrical, or other mechanical
forces.
[0032] Once on wheel 38, packs are guided by pushers 40 and hold
down guide 42. Packs 12 can then be loaded into a discharge
magazine 44 for final packaging.
[0033] A heating plate 36 according to the preferred embodiment of
the invention will now be described in greater detail. Although it
is anticipated that a heating plate 36 will be placed on both sides
of the heating area 32 to contact both ends of the packs 12, only
one plate will be described for convenience. The heater plate can
be comprised of any conventional material, though a material with
relatively high thermal conductivity is preferred.
[0034] As shown in FIG. 1, the packs can be placed in contact with
a heater plate 36 while in the heating area 32. FIG. 4 illustrates
one exemplary embodiment of the design of heater plate 36. Although
the heater plate 36 may have any number of stages, FIG. 4
illustrates a heater plate 36 with four stages. FIGS. 7-10 show in
phantom where the heater plate 36 contacts the packs 12.
[0035] Heater plate 36, as shown in FIG. 4 may be contoured. The
areas designated by numeral 50 can be contoured or flat and may all
be within the same plane. Areas 52 are illustrated as linearly
sloped, although they may be linear, contoured or may be
stepped.
[0036] The first stage 54 on the heater plate 36 may be flat. The
packs 12, and more particularly the wrapping 13, contact the flat
face of the heater plate 36 as shown in FIG. 7. First stage 54
uniformly preheats the surface of the wrapping. The heater plate 36
can have a notch 55 for any reason such as for mounting the plate
in the packaging apparatus 10 or for alignment.
[0037] The second stage 56 is a tacking stage. This stage typically
involves activating adhesive on the wrapping. As shown in FIG. 8,
the wrapping is contacted by members 57 at the points of contact 58
(shown in phantom in FIG. 8), the points where the largest bulk of
wrapping is folded upon itself. The wrapping can be five layers
thick due to the manner in which the ends of the wrapping are
folded.
[0038] The third stage 60 seals the wrapping 13. As shown in FIG.
9, an "H" member 61, so called because of its shape, contacts the
packs 12 in area 59 (shown in phantom in FIG. 9), along the folded
edges of the wrapping 13. The heating bonds the wrapping 13 to
itself along the edges of contact, thus sealing the pack from the
outside environment.
[0039] The fourth stage 62, known as the beauty bar shrink stage,
shrinks the wrapping 13 tight around the pack 12. The heater plate
has a surface with trapezoidal contact members 63, a first recessed
area 50 and a second recessed area 65. As shown in FIG. 10, contact
members 63 contact the packs 12 in areas 64 (shown in phantom in
FIG. 10), along the folded edges of the wrapping 13 while the
second recessed area aligns with packs 12 at area 66. To better
illustrate the different levels of the heater plate 36,
particularly with respect to the fourth stage 62, FIG. 6 shows the
heater block of FIG. 4 in profile along line 6-6. Packs 12 are
shown in phantom to further illustrate where the heater block 36
contacts the packs 12. The generally concavely contoured shape of
the beauty bar shrink stage 62 ensures proper heating to shrink the
wrapping 13 of pack 12 and eliminates any wrinkles 80 experienced
in the prior art as shown in FIG. 11, while avoiding melting the
wrapping. Thus an improved wrapped package 12 is produced as shown
in FIG. 12.
[0040] Heat is provided to the heater plate 36 by heater strips 70
on the rear side of plate 36 not facing the packs 12, as shown in
FIGS. 5A and 5B. Heater strips can be powered by a power source
(not shown) through wires 72. FIG. 5A shows the invention using two
heater strips 70, though any number of strips could be used to
obtain an optimal of temperature control. For example, FIG. 5B
shows four heater strips 70.
[0041] The heater plate can be maintained at one temperature of,
for example, approximately 140.degree. C.-170.degree. C., although
a higher or lower temperature is envisioned depending on the
wrapping material and other conditions. Additionally, the heater
stages could be set at different temperatures. For example, the
first and second stages could be maintained at a first temperature
of, for example, 150.degree. C., while the third and forth stages
could be set at a different temperature, for example, 170.degree.
C.
[0042] Heat can be provided by electrical resistive or inductive
heating, or in any other conventional manner. A thermocouple 74 can
be inserted at any or all of stages to monitor the temperature. The
heater plate 36 can be attached to the motor 37 by any means, for
example by bolts or by any other conventional means of attaching or
fixing including gluing, riveting or it may be formed
integrally.
[0043] The foregoing description of the invention illustrates and
describes the present invention. Additionally, the disclosure shows
and describes only the preferred embodiments of the invention, but
it is to be understood that the invention is capable of use in
various other combinations, modifications, and environments and is
capable of changes or modifications within the scope of the
inventive concept as expressed herein, commensurate with the above
teachings, and/or the skill or knowledge in the art of packaging
and, more particularly cigarette wrapping.
[0044] The embodiments described hereinabove are further intended
to explain best modes known of practicing the invention and to
enable others skilled in the art to utilize the invention in such,
or other, embodiments and with the various modifications required
by the particular applications or uses of the invention.
Accordingly, the description is not intended to limit the invention
to the form disclosed herein. Also, it is intended that the
appended claims be construed to include alternative
embodiments.
* * * * *