U.S. patent application number 10/800746 was filed with the patent office on 2005-09-22 for bagging of compressible bulk material.
Invention is credited to Berger, Regis, Lebel, Daniel, Lebel, Denis.
Application Number | 20050204709 10/800746 |
Document ID | / |
Family ID | 34984694 |
Filed Date | 2005-09-22 |
United States Patent
Application |
20050204709 |
Kind Code |
A1 |
Berger, Regis ; et
al. |
September 22, 2005 |
Bagging of compressible bulk material
Abstract
A method for bagging compressible particle material in bulk
compressed form comprising the steps of providing a compressed free
standing compressible particle material on a base, providing a
bagging apparatus with a stretchable bag having an open mouth with
a perimeter smaller than a body perimeter and than a base perimeter
when the bag is relaxed, using the bagging apparatus to stretch the
bag such that the mouth perimeter becomes larger than the body
perimeter and than the base perimeter, enclosing the body in the
bag through the open mouth until the body and a top part of the
base are contained therewithin, and releasing the bag so that a
sufficient memory of the bag allows the bag to provide a
compressing force on the top part of the base and body, the body
being sealed by the base and bag. A pack of compressible particle
material is also disclosed.
Inventors: |
Berger, Regis;
(Notre-Dame-du-Portage, CA) ; Lebel, Daniel;
(Escuminac, CA) ; Lebel, Denis; (Gardiner Point,
CA) |
Correspondence
Address: |
OGILVY RENAULT LLP
1981 MCGILL COLLEGE AVENUE
SUITE 1600
MONTREAL
QC
H3A2Y3
CA
|
Family ID: |
34984694 |
Appl. No.: |
10/800746 |
Filed: |
March 16, 2004 |
Current U.S.
Class: |
53/459 |
Current CPC
Class: |
B65B 25/02 20130101;
B65B 43/34 20130101 |
Class at
Publication: |
053/459 |
International
Class: |
B65B 009/12 |
Claims
1-5. (canceled)
6. A pack of compressible particle material comprising: a base; a
body of compressed particle material in bulk form upstanding freely
from the base and compressed directly thereon; and a bag enclosing
the body and producing a compressive force thereon so as to retain
the compressed particle material in bulk compressed form on the
base, the bag and base defining an enclosure completely enclosing
the body with the enclosure having a bottom constituted by the
base.
7. The pack according to claim 6, wherein the compressible particle
material is peat moss.
8. The pack according to claim 7, wherein the peat moss has a
water-content ranging from about 25 to about 50 weight % and a
density ranging from about 0.05 to about 0.15 gm/cc on dry
basis.
9. The pack according to claim 6, wherein the bag is made of a
fluid-impervious plastic tube sealed at one end thereof.
10. The pack according to claim 6, wherein the base is a
pallet.
11. The bag according to claim 6, wherein the bag is stretchable,
the bag having a mouth perimeter which is smaller than a body
perimeter when the bag is in a relaxed state.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to bulk shipping. More
particularly, the invention pertains to a method for palletizing
peat moss or the like in bulk compressed form as well as to the
palletized product obtained thereby.
[0003] 2. Description of the Prior Art
[0004] Owing to its unique porous structure, peat moss can absorb
from about 8 to about 20 times its weight in water. Such a high
absorption capacity renders peat moss particularly suitable for use
in absorbent products such as diapers, sanitary napkins, tampons
and the like. Peat moss is also widely used in horticulture as soil
adduct, compost, culture base, etc.
[0005] Peat moss is generally packaged in plastic bags for
shipment. A typical apparatus for packaging peat moss into bags is
described in Canadian Patent No. 1,043,310. The volume of a bag
filled with compressed peat moss is usually not larger than about
0.17 cubic meters in order to facilitate handling and shipping.
Thus, a single shipment of peat moss may comprise thousands of such
bags. The quantity of plastic bags utilized for packaging, and
discarded after use, is of course phenomenal and represents a
serious threat to the environment.
[0006] On the other hand, bulk shipping of peat moss in large
containers must be effected rapidly since a prolonged exposure of
peat moss to atmospheric oxygen causes a bacterial decomposition of
the peat moss. U.S. Pat. Nos. 5,477,658 and 5,699,915 issued to
Berger et al. disclose palletized peat moss in bulk compressed
form, wherein the peat moss is enveloped in a plastic wrap.
However, plastic wrap creates several joints between adjacent
plastic layers, which makes it difficult to obtain a sealed
package. Although using less plastic than standard small packages,
wrapping in bulk still necessitates a considerable quantity of
plastic, increasing production costs.
[0007] U.S. Pat. No. 3,961,459 to Wolske, U.S. Pat. No. 3,902,303
to King, and U.S. Pat. No. 3,621,638 to Grocke, all discloses
machines and methods for packaging palletized loads using stretched
plastic bags. However, these machines and methods are adapted for
rigid loads, such as boxes, and are thus not adequate for
compressible material such as peat moss.
SUMMARY OF THE INVENTION
[0008] It is therefore an aim of the present invention to provide
improved palletized peat moss in bulk compressed form.
[0009] Therefore, in accordance with the present invention, there
is provided a method for bagging compressible particle material in
bulk compressed form, the method comprising the steps of providing
a compressed quantity of free standing compressible particle
material on a base, the compressed particle material forming a body
holding a desired shape for a period of time sufficient to permit
bagging, providing a bagging apparatus with a stretchable bag, the
bag having an open mouth, a mouth perimeter being smaller than a
body perimeter and smaller than a base perimeter when the bag is in
a relaxed state, using the bagging apparatus to stretch the bag and
the mouth so that the mouth perimeter becomes larger than the body
perimeter and larger than the base perimeter, progressively
enclosing the body in the bag through the open mouth until the body
and at least a top part of the base are contained within the bag,
and releasing the bag so that a sufficient memory of the bag allows
the bag to provide a compressive force on the at least top part of
the base and body, the body being sealed in an enclosure formed by
the base and bag.
[0010] Also in accordance with the present invention, there is
provided a pack of compressible particle material comprising a
base, a body of compressed particle material in bulk form
upstanding freely from the base and compressed directly thereon,
and a bag enclosing the body and producing a compressive force
thereon so as to retain the compressed particle material in bulk
compressed form on the base, the bag and base defining an enclosure
completely enclosing the body with the enclosure having a bottom
constituted by the base.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Reference will now be made to the accompanying drawings,
showing by way of illustration a preferred embodiment thereof and
in which:
[0012] FIG. 1 is a side elevational view of palletized peat moss
according to a preferred embodiment of the present invention;
[0013] FIG. 2 is a perspective view of a apparatus for palletizing
peat moss according to a preferred embodiment of the present
invention;
[0014] FIG. 3 is a side elevational view of the palletized peat
moss of FIG. 1 prior to bagging;
[0015] FIG. 4 is a bottom plan view of a bag, illustrated in
relaxed and stretched form, before placing of the bag on the peat
moss of FIG. 3;
[0016] FIG. 5 is a side elevational view of the palletized peat
moss of FIG. 1 during bagging;
[0017] FIG. 6 is a side elevational view of the palletized peat
moss of FIG. 1 at the end of the bagging operation;
[0018] FIG. 7 is a block diagram schematically illustrating a
method of palletizing peat moss according to the preferred
embodiment of the invention; and
[0019] FIG. 8 is a block diagram schematically detailing the
bagging step of the method of FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] In the present invention, Sphagnum peat moss optionally in
admixture with mineral or organic aggregates is used as feedstock.
The peat moss should have a water-content ranging from about 25 to
about 50 weight % and a density ranging from about 0.05 to about
0.15 gm/cc on dry basis. If the water-content is too low, it is
adjusted to the desired content by adding water, for example, by
means of water sprays.
[0021] The peat moss is batch fed to a compression unit for direct
compression on a pallet. A predetermined quantity of peat moss is
held stacked vertically on the pallet to confine the peat moss to a
desired, compressed shape. The peat moss is compressed downwardly
onto the pallet at a pressure ranging from about 3 to about 5
kg/cm.sup.2 so as to form the peat moss into a coherent,
shaped-retaining body without substantially altering the
water-content and intrinsic properties of the peat moss. If
desired, an additional quantity of peat moss is fed to the
compression unit and compressed to increase the amount of peat moss
compressed on the pallet. The steps of peat moss feeding and
compressing may be repeated several times, although a single
compression stroke is preferred. The body of compressed peat moss
is then enveloped by a plastic film bag to retain the peat moss in
compressed form on the pallet.
[0022] As seen in FIG. 1, the palletized peat moss generally
designated by reference numeral 10 comprises a body of compressed
peat moss 12 upstanding from a pallet 14 and enveloped by a plastic
bag 16, the plastic bag retaining the peat moss 12 in compressed
form on the pallet 14. The pallet 14 is a conventional wooden
pallet comprising a top deck board fixed to three stingers arranged
in spaced-apart parallel relationship to one another, each stringer
being formed with three legs and aligned legs of the stringers
being interconnected by transverse slats. Typically, the palletized
peat moss 10 has a rectangular cross-section with a width of about
1.0 meter and a length of 1.2 meters, the height ranging from about
2.0 to about 2.5 meters. The volume of compressed peat moss
retained on the pallet generally ranges from about 2.5 to about 3.2
cubic meters.
[0023] The compression of the peat moss on the pallet so as to form
a shape-retaining body is done according to U.S. Pat. Nos.
5,477,658 and 5,699,915 previously mentioned and incorporated
herein by reference. The compression process will be briefly
explained herein below.
[0024] Referring to FIGS. 2 and 7, peat moss contained in a primary
reservoir 20 is unloaded into a secondary reservoir 22 until a
desire quantity is reached. Meanwhile, a housing is opened and a
pallet 14, preferably covered by a cardboard or plastic sheet, is
inserted within the open housing. The housing is then closed and
placed in a compacting station 24. While the housing can have a
number of different shapes, it is preferably prismatic. The pallet
14 closes a bottom end of the housing. Since compressed peat moss
has a tendency to expand, it is necessary to have a pallet with a
top surface cross-sectional area larger than the cross-sectional
area of the body of the compressed peat moss, to prevent the peat
moss from running the edges of the pallet when it expands. Thus,
the bottom part of the housing receiving the pallet 14 must be
larger than the rest of the housing receiving the peat moss.
[0025] Through a conveyor, the secondary reservoir 22 empties into
the compacting station 24 where the peat moss is received in the
housing through an open top end thereof. Fork arms extend under the
pallet so as to reinforce it during compaction. When the desired
quantity of peat moss is transferred into the housing, a piston and
cylinder operate to push a ram head downwardly into the housing to
compress the peat moss. After the compression stroke, the ram head
is raised. The housing is moved from the compacting station 24,
where it is opened and then returned to the compacting station 24,
thereby exposing the pallet supporting the shape-retaining body of
compressed peat moss behind.
[0026] The steps of the bagging process are generally illustrated
in FIG. 8. Referring to FIG. 3, the compressed peat moss body 12 on
the pallet 14 is placed in a bagging apparatus (indicated at 26 in
FIG. 2). A plurality of arms 40, preferably one for each of the
four corners of the pallet 14, hold a bag 16 directly over the peat
moss body 12. The bag 16 is formed from a plastic tube sealed at a
top end thereof with an open bottom end forming a bag mouth 18
which is aligned with the peat moss body 12. In a relaxed state,
the bag mouth 18 has a perimeter which is smaller than a perimeter
of the peat moss body 12 and of the pallet 14. A support 42 is
engaged with the bottom of the pallet 14.
[0027] Referring to FIG. 4, the arms 40 then diagonally stretch the
bag 16 from a relaxed state, indicated in phantom lines, to obtain
a stretched bag 16'. The stretched bag 16' defines a stretched bag
mouth 18' which has a larger perimeter than the perimeter of the
peat moss body 12 and of the pallet 14.
[0028] Referring to FIG. 5, the arms 40 lower the stretched bag 16'
onto the peat moss body 12. As the stretched bag 16' is
progressively released from the arms 40, it regains at least
partially its original size 16, with a perimeter smaller than the
perimeter of the peat moss body 12, and thus compresses it.
[0029] Referring to FIG. 6, before the arms 40 reach the pallet 14,
a piston 44 pushes the support 42 to lift the pallet 14 from the
ground to allow the arms 40 to place the stretched bag 16' over a
top part of the pallet 14. The arms 40 then release the stretched
bag 16' which regains at least partially its original size 16, and
the pallet is brought back down. The bag 16 thus compresses the
peat moss body 12 and the top part of the pallet 14, and thus forms
with the pallet 14 an enclosure surrounding the peat moss body 12
and maintaining it in a compressed state to form palletized peat
moss 10, as shown in FIG. 1.
[0030] Because the peat moss is highly compressible, standard
plastic bags used with solid palletized loads are usually not
appropriate to form the bag 16. The memory of the plastic, i.e. its
capacity to return to its initial shape after deformation, must be
sufficient to maintain the peat moss in compression. This is
usually not the case in plastic bags used with solid palletized
load where the compression force applied by the bag is
significantly smaller. Also, the transition from a solid pallet to
a soft body of compressed peat moss forms a stress concentration on
the bag along that transition, especially around the corners of the
pallet. The plastic used thus has to be sufficiently resistant to
tearing, typically twice as much as standard plastic used with
solid palletized loads, to preserve the integrity of the enclosure
protecting the palletized peat moss.
[0031] The palletized peat moss 10 contained within a bag 16
presents several advantages over a similar palletized peat moss
wrapped in plastic film. First, the elimination of the numerous
joints between adjacent plastic layers greatly improves the sealing
of the peat moss, thereby improving the shelf life of the packed
product. Also, the bag 16 necessitates less plastic material than a
wrap, thus reducing the cost of producing the palletized peat moss
and the impact of the discarded packaging material on the
environment. Bagging implies a single downward motion, while
wrapping necessitated several turns around the peat moss body; the
bagging process thus takes less time, increasing production.
Finally, the appearance of the bagged pallet of peat moss is more
esthetically pleasing than a similar wrapped pallet of peat
moss.
[0032] While the present process has been described with respect to
peat moss, it could be applied to a number of granular or small
particle materials that can be compressed such as to form a
free-standing body. The pallet could also be replaced by any other
appropriate rigid base.
[0033] The embodiments of the invention described above are
intended to be exemplary. Those skilled in the art will therefore
appreciate that the forgoing description is illustrative only, and
that various alternatives and modifications can be devised without
departing from the spirit of the present invention. Accordingly,
the present is intended to embrace all such alternatives,
modifications and variances which fall within the scope of the
appended claims.
* * * * *