U.S. patent application number 09/359490 was filed with the patent office on 2002-01-10 for packaging method.
Invention is credited to KONDO, MASASHI, NAKAGAWA, YUKIO.
Application Number | 20020002810 09/359490 |
Document ID | / |
Family ID | 16548646 |
Filed Date | 2002-01-10 |
United States Patent
Application |
20020002810 |
Kind Code |
A1 |
NAKAGAWA, YUKIO ; et
al. |
January 10, 2002 |
PACKAGING METHOD
Abstract
Packages are each made by clamping a tubularly formed bag-making
film, dropping a batch of articles into this film while it is in
this clamped condition, and shaking this batch of articles to
thereby increase its volume density. This is done once or repeated
any number of times. After articles of the final batch are dropped
into the film, the clamped condition of the film is released and
the articles are dropped further downward to the bottom of the bag
being made. The tubularly formed film is thereafter sealed
transversely above the articles which have been received to close
the bag.
Inventors: |
NAKAGAWA, YUKIO; (SHIGA,
JP) ; KONDO, MASASHI; (SHIGA, JP) |
Correspondence
Address: |
COUDERT BROTHERS
600 BEACH STREET
SAN FRANCISCO
CA
94109
US
|
Family ID: |
16548646 |
Appl. No.: |
09/359490 |
Filed: |
July 22, 1999 |
Current U.S.
Class: |
53/437 |
Current CPC
Class: |
B65B 1/22 20130101; B65B
9/2007 20130101; B65B 9/207 20130101; B65B 9/213 20130101; B65B
51/306 20130101 |
Class at
Publication: |
53/437 |
International
Class: |
B65B 001/22 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 23, 1998 |
JP |
10-207977 |
Claims
What is claimed is:
1. A packaging method comprising the steps of: clamping a tubularly
formed film with a shaker; dropping a batch of articles into said
film while said film is in a clamped condition by said shaker;
shaking the dropped batch of articles by means of said shaker to
thereby increase volume density of said batch of articles;
releasing said film from said clamped condition to thereby further
drop the shaken batch of articles after articles of a final batch
are dropped into said film; and thereafter sealing said tubularly
formed film transversely above the dropped articles.
2. The packaging method of claim 1 further comprising the step of
preliminarily specifying a packaging speed, the steps of claim 1
being carried out and said film being transported intermittently
each time by a specified bag length if packages are produced at a
slower rate than the specified packaging speed, said film being
transported continuously and said shaker remaining inactive if
packages are produced at a faster rate than the specified packaging
speed.
3. The packaging method of claim 1 further comprising the steps of:
preliminarily storing a reference value; inputting packaging
conditions for producing packages through an input device;
comparing said reference value with said packaging conditions by
means of a control unit; transporting said film intermittently each
time by a bag length according to said packaging conditions and
carrying out the steps of claim 1 if said control unit concludes by
the step of comparing that said film should be transported
intermittently; and transporting said film continuously while
keeping said shaker inactive if said control unit concludes by the
step of comparing that said film should be transported
continuously.
4. The packaging method of claim 1 wherein said shaker shakes said
film in an up-and-down motion.
5. A packaging method comprising the steps of: intermittently
transporting a tubularly formed film; clamping said tubularly
formed film at a clamping position with a shaker; dropping a first
batch of articles which is about one half of a predetermined target
total amount into said tubularly formed film in a clamped condition
by said shaker; shaking said first batch of articles above said
clamping position by means of said shaker; thereafter dropping a
second batch of articles into said tubularly formed film, releasing
said film from said clamped condition and transversely sealing said
tubularly formed film below said clamping position to form a bottom
of a bag, said first batch and said second batch of articles
together having said target total amount; thereafter stopping
transportation of said tubularly formed film; thereafter clamping
said tubularly formed film with said shaker at a next clamping
position on said film; thereafter dropping another first batch of
articles into said tubularly formed film in the clamped condition
by said shaker; and thereafter shaking simultaneously both said
another first batch of articles above said next clamping position
and said first batch and said second batch of articles below said
next clamping position on said tubularly formed film.
6. The packaging method of claim 5 wherein said tubularly formed
film is transported along a film path and said shaker is disposed
on said film path.
7. The packaging method of claim 5 wherein said shaker shakes said
film in an up-and-down motion.
8. A packaging machine comprising: a pull-down mechanism for
pulling a bag-making film downward while bending said film into a
tubular form; a transverse sealer for transversely sealing said
tubularly formed film; a shaker disposed between said pull-down
mechanism and said transverse sealer for clamping said tubularly
formed film at a specified clamping position and thereby shaking
articles held inside said tubularly formed film above said clamping
position; and a control unit for causing a plural n-number of
batches of articles to be sequentially dropped into said tubularly
formed film while said film is in a clamped condition by said
shaker, shaking articles inside said film after each of the first
(n-1) of said n batches of articles is dropped into said tubularly
formed film, and releasing said film from said clamped condition
after the last of said n batches of articles is dropped into said
tubularly formed film.
9. The packaging machine of claim 8 further comprising an input
unit through which packaging conditions are inputted to said
control unit, said control unit further serving to store a
preliminarily determined packaging speed, comparing said packaging
conditions inputted through said input unit with said preliminarily
determined packaging speed, and causing said pull-down mechanism to
transport said tubularly formed film accordingly either
intermittently or continuously.
10. The packaing machine of claim 9 wherein said control unit keeps
said shaker inactive if said pull-down mechanism is controlled to
transport said tubularly formed film continuously.
11. The packaging machine of claim 8 wherein said shaker shakes
said tubularly formed film in an up-and-down motion.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to a packaging machine and a method
of making packages by means of a packaging machine. More
particularly, this invention relates to a method of making packages
by increasing the volume density of the articles that are to be
packaged and a packaging machine which makes use of such a
method.
[0002] Packages of articles which are easily breakable and low in
volume density, such as potato chips, are difficult to handle
efficiently because a large amount of package-making material is
required to package them and the costs of their transportation are
high. In view of this problem, U.S. Pat. No. 5,540,035, for
example, disclosed a method of shaking the articles which have been
dropped into a bag before it is sealed such that the volume of the
batch of articles to be sealed in is reduced. If this technology is
applied to a large-scale packaging machine adapted to package twice
or three times more articles in each bag than a packaging machine
of a normal size, however, it is not possible to effectively
increase the volume density of articles inside the bag, and the
packaging speed is adversely affected significantly.
SUMMARY OF THE INVENTION
[0003] It is therefore an object of this invention in view of this
problem of the prior art technology to provide an improved method
of producing large packages while efficiently increasing the volume
density of the articles, as well as a packaging machine using such
a method.
[0004] A packaging method embodying this invention, with which the
above and other objects can be accomplished, may be characterized
as comprising the steps of clamping a tubularly formed bag-making
film with a shaking mechanism (herein referred to as the shaker),
dropping a batch of articles into this film while it is in this
clamped condition, and shaking this batch of articles by activating
the shaker to thereby increase its volume density. This is done
once or repeated any number of times, and after articles of the
final batch are dropped into the film, the clamped condition of the
film is released and the articles are dropped further downward to
the bottom of the bag being made. The tubularly formed film is
thereafter sealed transversely above the batches of articles which
have been dropped to close the bag.
[0005] The user may use an input device to input various packaging
conditions such as the length of each bag to be made and the
packaging speed (that is, the number of packages to be produced per
unit time). A packaging machine according to this invention
includes a control unit which determines whether the film should be
transported intermittently or continuously by comparing at least
one of the inputted packaging conditions and a preliminarily stored
value such as a packaging speed. The steps described above are
carried out if the control unit concludes that the film should be
transported in an intermittent mode. If the control unit concludes
that the film should be transported in a continuous mode, the film
is pulled down in a continuous motion without subjected to the
shaking by the shaker.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The accompanying drawings, which are incorporated in and
form a part of this specification, illustrate embodiments of the
invention and, together with the description, serve to explain the
principles of the invention. In the drawings:
[0007] FIG. 1 is a schematic representation, in part as a block
diagram, of a packaging machine embodying this invention;
[0008] FIGS. 2A and 2B are respectively a plan view and a side view
of the shaker of the packaging machine of FIG. 1;
[0009] FIGS. 3A, 3B, 3C, 3D, 3E and 3F are schematic drawings for
showing the sequence of packaging operations by the packaging
machine of FIG. 1 in an intermittent mode of film
transportation;
[0010] FIG. 4 is a timing chart for the packaging operations of
FIGS. 3A, 3B, 3C, 3D, 3E and 3F;
[0011] FIGS. 5A, 5B, 5C, 5D and 5E are schematic drawings for
showing the sequence of packaging operations by the packaging
machine of FIG. 1 in a continuous mode of film transportation;
and
[0012] FIG. 6 is a timing chart for the packaging operations of
FIGS. 5A, 5B, 5C, 5D and 5E.
DETAILED DESCRIPTION OF THE INVENTION
[0013] The invention is described next by way of an example. FIG. 1
shows schematically the structure of a packaging machine embodying
this invention. An elongated bag-making material (the "film") 100
is transported to a former 2 to be thereby bent into a tubular form
around a tubular structure which is integrally formed with a hopper
1, and is pulled down along this tubular structure by means of a
pair of pull-down belts 31 (only one of the pair being visible in
FIG. 1) driven by a belt-driving motor 33 controlled by a control
unit 9. The pair of pull-down belts 31 and a longitudinal sealer
32, comprising a heater to seal together the mutually overlapping
side edges of the film 100, together form a pull-down mechanism 3,
disposed below the former 2.
[0014] Disposed below this pull-down mechanism 3 and immediately
above a transverse sealer 7 is a shaker 5 for causing the articles
being dropped from a weigher (not shown) into the interior of the
bag in the making, while clamping the tubularly formed film 100 in
an coordinated way with the operation of the weigher such that the
volume density of the articles will be increased. The transverse
sealer 7 is for sealing the tubularly formed film 100 in the
transverse direction and comprises a pair of seal jaws 71 and
jaw-operating motors 73 and 74 controlled by a control unit 9 for
causing the pair of seal jaws 71 to undergo a cyclic motion along
generally D-shaped trajectories, as disclosed more in detail, for
example, in U.S. Pat. No. 5,753,067. Numeral 10 indicates an input
device through which a user may input "packaging conditions", such
as the length of the bags to be produced, the target weight of
articles to be packaged in each bag, the packaging speed or the
number of packages to be produced per unit time, on which
operations of various kinds are to be carried out.
[0015] Explained more in detail, the shaker 5 is adapted to clamp a
portion of the film 100 periodically, once every time the film 100
is pulled down by a distance equal to the length of the bags being
made. In a mode of operation wherein articles with a desired total
weight are dropped successively in two batches to produced a
packaged bag, for example, the shaker 5 shakes the articles of the
first batch which are dropped in first, thereby increasing their
volume density. The shaker 5 then releases the clamping as articles
of the second batch are dropped into the film 100. As a result, the
articles fill the interior of the tubularly formed film 100 at an
increased volume density with the bottom of the bag sealed
transversely.
[0016] FIGS. 2A and 2B show the structure of this shaker 5 more in
detail. Its main body (the "shaker main body") 51 is in the form of
a frame, surrounding the tubularly formed film 100, and is attached
to a pair of left-hand side and right-hand side frame structures 53
through a shaft 52 penetrating the shaker main body 51 in the
direction of its width (the vertical direction in FIG. 2A) so as to
be able to oscillate. At one end of the shaker main body 51 in its
longitudinal direction (the horizontal direction in FIG. 2A) is a
longitudinally extending shaft 54 which is eccentrically coupled
through a connecting bar 58 with the shaft 56 of a decelerating
gear 55 such that the rotary motion of a shaker motor 57 for
shaking, controlled by the control unit 9, is converted into an
up-and-down motion such that the main body 51 will undergo an
oscillatory motion in the vertical direction around the shaft
52.
[0017] A pinion 61 is affixed to one end of this shaft 52
penetrating the shaker main body 51, engaging a rack 60 which is
adapted to be driven by a driver cylinder 59, controlled by the
control unit 9, to undergo a reciprocating forward-backward motion
in the longitudinal direction. A belt 64 is supported between a
driver pulley 62 affixed to the shaft 52 and a follower pulley 63
on the shaker main body 51. A pair of shutters 66 and 67 is
attached to the mutually oppositely facing surfaces of this belt 64
such that these shutters 66 and 67 can be moved towards or away
from each other by moving the rack 60 backward and forward to move
the belt 64.
[0018] In FIG. 2, numeral 68 indicates a sensor for counting the
number of oscillations of the shaker main body 51 by detecting a
plate 69 attached to the shaft 56 of the decelerating gear 55. The
control unit 9 serves to control the operations of the motions of
the motors 33, 57, 73 and 74 for the pull-down belts 31, the shaker
main body 51 of the shaker 5 and the transverse sealer 7. The
timing for the control of these motors by the control unit 9 is
explained next with reference to sketches in FIGS. 3A, 3B, 3C, 3D,
3E and 3F, as well as the timing chart of FIG. 4.
[0019] If the packaging speed inputted through the input device 10
is greater than a preselected specified value ("specified packaging
speed") preliminarily stored in the control unit 9, or if articles
to be packaged together to make one package are dropped together
all at one as a single batch according to a selected mode of
operation, the control unit 9 carries out a normal continuous mode
of film transportation, transporting the film 100 in a continuous
manner without shaking the articles which have been dropped in. If
the inputted packaging speed through the input device 10 is less
than the specified packaging speed, or if the articles with a
target total weight are dropped successively in a plurality of
batches according to a selected mode of operation, on the other
hand, the control unit 9 advances the film 100 intermittently by a
distance equal to the length of the individual bags to be made.
[0020] Let us now consider a mode of operation wherein articles
having a target total weight are dropped successively in two
batches, each weighing about one half of the target weight. This
mode of operation is described, for example, in U.S. Pat. No.
4,508,185 and hence will not be described herein in detail. After a
cycle of operations including weighing and packaging (say, at time
t.sub.a in FIG. 4), the seal jaws 71 of the transverse sealer 7 are
stopped at specified initial positions (indicated by numeral 710 in
FIG. 1) immediately before they contact each other, the shutters 66
and 67 of the shaker 5 are stationary while clamping the tubularly
formed film 100 as shown in FIG. 3A, and the pull-down belts 31 are
at rest. When the weigher receives a ready signal from the
packaging machine under this condition, requesting a discharge of
weighed articles, a batch of articles with a total weight equaling
about one half of the target total weight is measured and dropped
into the tubularly formed film 100 in a clamped condition, and the
shaker motor 57 rotates for a specified length of time T1 (from
time t.sub.b in FIG. 4), causing the shaker main body 51 to
oscillate up and down around the shaft 52 so as to increase the
volume density of the articles which have been dropped, as shown in
FIG. 3B. Thereafter, when a second batch of articles weighing also
about one half of the target total weight (such that the sum of the
weights of the first and second batches of articles equals the
target total weight) is dropped from the weigher as shown in FIG.
3C in response to another ready signal outputted from the packaging
machine and a discharge-end signal indicative of the completion of
a discharge of articles is returned from the weigher at time
t.sub.c, the motors 73 and 74 for the seal jaws 71 begin to rotate
after a short wait period of T2. After still another period of time
T3 (at time t.sub.d), the seal jaws 71 engage each other
immediately before the articles of the second batch reach the
shaker 5 and seal the bottom edge of the bag being formed. At the
same time (at time t.sub.d), the downward motion of the film 100 is
started in synchronism with the rotary motion of the seal jaws 71
and the driver cylinder 59 is also activated so as to cause the
pair of shutters 66 and 67 to move away from each other through the
rack 60, the pinion 61 engaging with the rack 60, the driver pulley
62 which rotates with the pinion 61, and the belt 64 stretched
between the driver pulley 62 and the follower pulley 63. As a
result, the articles of the first batch of which the volume density
has been increased by the shaker 5 and the articles of the second
batch received subsequently are together dropped into the bag being
formed with its bottom edge sealed between the seal jaws 71, as
shown in FIG. 3D.
[0021] The film 100 is pulled down by the pull-down belts 31 at the
same speed as the downward motion of the seal jaws 71 on the
straight line portions of their generally D-shaped trajectories. By
time t.sub.c when the film 100 is pulled down by a distance equal
to the length of the bag being made, the first and second batches
of the articles are together completely inside and the seal jaws 71
are back at their specified initial positions 710, as shown in FIG.
3E. After the downward motion of the film 100 is also stopped
around the same time, the shutters 66 and 67 wait for a specified
period T4 until the dropped articles settle and then clamp the film
100 above these articles. At the same time t.sub.f, the shaker 5 is
activated again as shown in FIG. 3F, causing the shaker main body
51 to oscillate around the shaft 52 up and down so as to increase
the volume density of not only the articles of the second batch
already inside the closed bag but also the next batch of articles
dropped in the meantime for the next bag to be produced. Thus, a
space is created above the enclosed articles for transversely
sealing the film 100 with the seal jaws 71, and the sequence of
steps described above is repeated thereafter.
[0022] Let us consider next a situation wherein the film 100 is
pulled down in a continuous manner and articles having a target
total weight are dropped in together as a single batch. In this
mode of operation, the shutters 66 and 67 remain open and the
shaker 5 is kept inactive. FIG. 5A shows a situation at time
t'.sub.a as shown in FIG. 6 prior to the output of a ready signal.
If a ready signal is outputted from the packaging machine (at time
t' .sub.b in FIG. 6) under this condition and the weigher
discharges weighed articles in a single batch and outputs a
discharge-end signal (at time t'.sub.c in FIG. 6), the control unit
9 causes the jaw-operating motors 73 and 74 to start moving the
seal jaws 71 and the belt-driving motor 33 to start pulling down
the film 100 after waiting for a predetermined period of time T2
(at time t'.sub.d) as shown in FIGS. 5B and 5C such that the seal
jaws 71 close the bag in time to receive the article batch
thereabove, as shown in FIG. 5D. Thereafter, the seal jaws 71
continue to rotate and the film 100 continues to move down as shown
in FIG. 5E, and the seal jaws 71 transversely seal the film 100 to
form simultaneously the top seal of the bag which has just been
filled and the bottom seal of the bag to be filled in the next
cycle of operation. If the next ready signal is thereafter
outputted from the packaging machine (at time t'.sub.e) and a
discharge-end signal is received from the weigher in response, the
pull-down belts 31 is continuously rotated and the seal jaws 71 are
caused to undergo another cycle of rotary motion at the same time,
as described above. If no discharge is made and no discharge-end
signal is accordingly outputted from the weigher, for whatever
reason, as indicated by a dotted line at time t.sup.tf in FIG. 6,
the control unit 9 causes the seal jaws 71 to complete the
transverse sealing to thereby close the top end of the bag which
has just been filled in the previous cycle of operation and to
return to, and to rest at, their specified initial positions 710,
stopping the pull-down belts 31 after a predetermined period of
time TS has elapsed from the moment when a discharge-end signal was
normally to be received, as shown in FIG. 6.
[0023] Although the invention has been described above for a mode
of operation wherein articles with a target total weight are
dropped in two batches to make each package, the articles of the
first batch being shaken after being dropped such that their volume
density is increased before the articles of the second batch are
dropped, this is not intended to limit the scope of the invention.
In general, articles with a target total weight may be dropped
consecutively in n batches where n may be any integer equal to or
greater than 2, and the bag may be shaken by the shaker after
articles of each of the first (n-1) batches have been dropped.
Articles of all n batches are added together to form one package
only after the articles of the n.sup.th batch (the "final batch")
are dropped.
[0024] Thus, the bag is shaken after each time articles of one of
the first (n-1) batches are dropped such that their volume density
is increased, and the bag is finally sealed and shut after the
final batch of articles is dropped in. In this manner, packages
with a smaller volume can be produced according to this invention
such that their costs of production as well of transportation can
be significantly reduced. Since this operation for increasing the
volume density of the articles is carried out simultaneously with
the transverse sealing of the film, the packaging speed is not
adversely affected. In a mode of operation wherein the tubularly
formed film is transported intermittently, furthermore, the speed
of film transportation can be increased to thereby increase the
distance along which the film is stroked such that the so-called
browsing effect can be enhanced.
[0025] The disclosure given above is intended to be interpreted
broadly. It goes without saying that the packaging machine of this
invention can be operated not only with a weigher adapted to drop
in article batches according to their weights but also with an
device adapted to supply article batches according to their volumes
or number of individual articles.
* * * * *