Note: Descriptions are shown in the official language in which they were submitted.
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FIELD OF THE INVENTION
The present invention rela~es to a pallet
wrapp r. More specifically the present invention relakes
to an automatic pallet wrapper adapted to apply an
untreated wrapping or netting material about a pallet
and secure it in position.
BACKGROUND OF THE INVENTION
There are many dif~erent forms of pallet wrappers
currently available. Most of them operate on the
principal of the pallet being positioned on a table or
platform, the table rotated to wrap a web of material
which is applied to the pallet load, around the pallet
load and to cut of~ and wipe the end of the web against
the pallet and thereby securing the wrapper in position
i.e. the wrapper web is applied to the pallet and the
pallet rotates to wind the web around the pallet and
overlap itself. This wrapping is continued until the
top of the pallet is reached and normally reverses itself
: back down to the bottom of the pallet. The web is
treated with a special finish so that when the web is
cut-off after wrapping, the cut-off end adheres to the
layers of wab prevlously applied to the pallet.
Pallet wrappers wherein the wrapping material
is suspended from above or below and travel around the
pallet are also known and operate in a similar manner.
Such wrapper materials are normally not particul-
arely porous and do not permit significant breathing of
the pallet load which can lead to condensation or, in
many cases, overheating of the pallet load resultiAg in
deterioration of the goods contained in the pallet.
Web material formed of an opened weave, such
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as a leno-type weave material has long been known and
recently a plastic open mesh material has been provided
that has adequate strength to properly wrap a pallet,
however, these materials have, ln the past, always
required manual application, thereby limitiny severally
their use. Even though the open weave material is far
superior from a breathing and heat transmission point of
view improving the stability of the pallet load under
various conditions of temperature and humidity while
providing adequate, strength to hold the pallet load to-
gether, its use has been restricted due to the lack of
automatic wrapping equipment. Similarly, untreated plastic
wrapping sheet material could not be wrapped automatically.
BRIEF DESCRIPTION OF THE INVENTION
The object of the present invention is to provide
an improved automatic pallet wrapper capable of handling
untreated sheet material or net-like material.
Broadly the present invention relates to a
pallet wrapper compri~ing; a source of wrapping material,
an anvil movable ~rom a remote position to a position in
contact with one side of a pellet load, thereby to
accurately locate the side of the pallet, clamping means
or holding the end of said web wrapping material movable
with said anvil to a position adjacent said pallet, secur-
ing means for securing said wrapping materi~l to a section
of said wrapping material previously wrapped around said
pallet and a cut-off mechanism for cutting said web
material after said securing means has secured said web.
The wrapper further comprises a roping mechanism for
converting a portion of the web of wrapping material
into a rope form and a positioning member for moving the
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roped portion into position to be engaged by the clamping
means.
The present invention also relates to a method
of wrapping a pallet which comprises positioniny a pallek,
moving an anvil member into engagement with the side of
said pallet, simultaneously moviny an end o a web
held in a clamp positioned adjacent said anvi.l, wrapping
said web about said pallet at least sufficient turns so
that the clamped end of said web is overlapped and
lQ frictionally retained by a further portion of said web
overlapping said anvil and said end held in said clamp,
releasing said clamp, withdrawing said clamp to a position
clear of said w~b, completing the wrapping of said pallet
while roping a last portion of said web wrapping said
pallet to provide a roped section, moving said clamp
into operative position and clamping a roped portion of
said web, forcing said web adjacent said clamp toward
said anvil and securing said web to proviously applied
section of said web adjacent said anvil, cutting said web
between said clamping means and the location at which said
web i5 fastened to said other previously applied section,
retracting said anvil and moving said wrapped pallet
Further features, objects and advantages will be
evident from the following detailled description of the
preferred embodiment of the present invention taken in
conjunction with the accompanying drawings, in which:
Figure 1 is a plan view schematically illustrating
the pallet wrapper of the presen-t invention.
Figure 2 is a side elevation schematically
illustrating the present invention.
Figure 3 is a schematic isometric view of the
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anvil member and clamp, schematically illustrating the
mechanism for positioniny the anvil and or moving same
from an operative to an inoperative position and or
positioning the clamp and moving it to an unextended and
a retractive position.
Figure 4 shcematically illustrates the position
of the anvil, clamp and web as wrapping of the pallet is
begun.
Figure S shows the pallet wrapped for at least
sufficient turns to secure the wrapper about the pallet
so that the clamp may be released.
Figure 6 is a shematic illustration of the roping
mechansim about to form a portion of the web into a rope
configuration as the wrapping operation is completed.
Figure 7 shows the positioning mechanism moving
in engagement with -the roped portion of the web and holding
it in a position for the clamping mechanism to move into
extended position and clamp the rope and is the section taken
along the lines 7-7 of figure 1.
Figure 8 is a side view of the clamping mechanism
holding the roped portion of the web.
Figures 9, 10, 11 and 12 are plan views illustrat-
ing the sequence of operation of the various mechanisms.
Figure 9 shows the carriage in advanced position. Figure
10 is a plan view of what is illustrated in figure 8.
Figure 11 illustrates the~ fastening means in operative
position and figure 12 ~he cut-off mechanism in operative
positio~.
Figure 13 illustrates the web cut-off and fastened
with the free end of the web held in the clamp and with
the anvil member retracted to complete the wrapping of the
pallet.
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Figure 14 is an isolated view of one ~orm of
roping means.
As shown in figure 1, the pallet wrapper o~ ~h~
present invention preferably comprises, a bas0 10 wi~h
a platform 12 mounted thereon and adapted to rotate
relative to the base. A roll of wrapping material 14
is m~unted on the base 10 on a suitable elevator mechanism
16 which raises and lowers the roll 14 during the wrapping
operation in the well known manner.
Mounted on the platform 12 is an anvil and clamp-
ing mechanism generally indicated at 18 (illustrated
schematically in more detail in figure 3). This mechanism
13 comprises a movable guide member 20 mounted on a suitable
track (not shown) on the platform 12~ The guide 20 is
positioned below the upper suxface of the platform 12 and
is moved relative to the platform 12 by a suitable
mechanism generally indicated by the piston 22 in figure
3.
Mounted in suitable vertical tracks 24 in the
guide 20 is an anvil member 26 which is adapted to be
moved from a retracted position to an extended position
via the plston and cylinder arrangement schematically
illustrated at 28 so that the anvil 26 is moved vertically
relakive to the guide member 20.
Also mounted on the guide member 20 is a clamp
generally indicated at 30 and movable vertically relative
to the guide member via a suitable piston and cylinder
arrangement 32. Suitable means 34 may be activated to
~ close the clamp 30, however, the clamp 30 will preferably
open simply by a spring action.
As illustrated in ~igure l, a carriage 15 is
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movable on base 10 by suitable means such as p s-ton and
cylinder 13 toward and away from the platorm 12 and is
accurately positioned relative to the anvil memher 18
by means of a bumper 17 projecting rom in ~ront o~ th~
carriage. The bumper 17 is a conventional ~luid
bumper and operates to stop the movement o~ the carriaye
15 towards the platiorm 12 by stopping flow of fluid to
the piston and cylinder 13 when the ~luid pressure
generated by forcing the bumper 17 against the anvil
member 26 reaches a certain pre-set level i.e. it
ensures that the carriage 15 is positioned a specified
distance from the anvil member 26 and terminates the
movement of the carriage 15 when said predetermined
pressure is reached.
Mounted on the carriage 15 is a sùitable
positioning element 36 as well as a cut-off mechanism
38 and a securing mechanism 40 each such mechanism
being independently moved toward and away from the anvil
26. These instrumentalities 36, 38 and 40 are simply
illustrated schematically as the particular form thereof
does~not constitute part of the present invention. How-
ever, it should be stated that the cut-off mechanism for
example, would normally be composed by a pair of shears
that are moved into an operative position and then through
a cutting motion i.e. the operating shears e.g. a pair of
scissors would be extended to cutting position and then
rotated on their pivot to cuto Similarly the s2curing
mechanism may simply constitute a stapling device for example
a davice used or s~aplin~ upholstry or in the manufacture
of mattresses. This device is moved into a proper
postion relative to the anvil and then the staple is set.
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Both of these devices may be activated pneumatically wi~h
the initial movement of the piston of the pneumatic
cylinder moving the device into operative positlon and
the final portion of the movement o the piston activating
the device to cut or staple.
Also mounted on the base 10 is a roping mechanism
42 which is composed of an arm 44 ~ormed for example rom
a piece o bent steel rod which is pivotably mounted as
indicated at 43 at one side of the web 50 extending from
the roll 14 and under the web 50 to the opposite side
thereof. ~he arm 44 is formed with a loop or hook 45 on
the side of the web 50 opposite the pivot 43 and terminates
in an upstanding section 47 adapted to direct the web
into the loop 45 (see figure 14) i.e. when the roper 42
is activated by pivoting on pivot 43 to move the loop 45
towaxd the pallet being wrapped, the section 47 brases
the top portion of the web 50 toward the loop 45 and as
the roll 14 approaches its lowest position with the roper
42 activated the lower edge of the web 50 engages the arm
44 and is biased into the loop 45 which forms the web 50
into a rope section 46 Isee figures 6-13).
Generally the positioning element 36 may simply
comprise an open V-shaped element fixed to the platform
15 in a position to engage a roped portion 46 of the web
50 between the loop 45 and the clamp 30 close to clamp
30 i.e. when the platform 15 is advanced the roped section
46 enters the open V-shaped element 36 that insures the
rope 46 is in a position to be engaged by the clamp 30
when it is moved up to clamp the web (see figures 9, 11
and 12~.
Having broadly described the structure of ths
invention, the operation will be described to better
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illustrate the concept.
First the pallet generally indicated at 52 is
positioned on the platform 12, next the anvil member 26
is raised to an elevated position above the surface of
the platform 12 and the guide member 20 i5 moved toward
the pallet 52 until the anvil 26 contacts wlth the pallet
S2. At t,his point the pressure in the cylinder piston
arrangement generally indicated at 22 begins to increase
and when it reaches a pre-set level it automatically
cuts-off (in a well known manner) thereby maintaining the
anvil 25 in raised position against the side of the pallet.
At this point in time, the clamp member 30 is in elevated
postiion and has the free roped end of the web 50 clamped
therein as indicated in figure 4. The roping mechanism
42 is in inoperative position.
With the mechanism as illustrated in figure 4,
the pallet 52 is rotated by rotating the platform 12 which
wraps the web 50 around the periphery of the pallet 52
until the web 50 overlaps itself and the anvil 26 as
well as the clamp 30 and the portion of the web 50
extending from the clamp 30 as shown in figure 5~ After
the web 50 has been wrapped around the pallet sufficiently
to frictionaLly hold the end retained in the clamp in
postion against the pallet, the clamp 30 is released
and retxacted downwards. This generally requires about
1-l/4 turns of the web 50 about the pallet. Obviously,
the clamp 30 will not open completely until it is clear
of the overlying portion of the web 50 as there is no
room for it to open since the web 50 is pulled tightly
thereover. However, it will release enough to slide
down and leave the end portion trapped under the next
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overlying layer of the web 50.
At this point the anvil will be wrapped by the
web 50 i.e. it will be between the pallet 52 and the
wrapper 50.
The wrapping o the pallet 52 is continued until
the wrapper has proceeded to the top of the pallet and
back down towaxd the bottom of the pallek when the web
50 is wrapping near to the bottom of the pallet the
roping mechansim 42 will be activated so that the arm 44
moves clockwise, the upstanding section 47 engages the
web 50 as does the top of the arm 44 to fold the web 50
into a roped shape 46 and wedge it into the loop 45.
Generally the last about 1-1/4 turns around the bottom of
the pallet will be roped as indicated in ~igure 6.
After the web has completely wrapped the pallet,
the platform 12 is moved into position so that the web
50 passing from the pallet to the roll 14 extends adjacent
the anvil 26. At this point the roper 42 i5 in active
position and the carriage 15 is moved to advanced position
a pre-set distance from anvil 26 as determined by the
bumper 17 (see figura 9) and the positioning element 36
engages the rope section 46 ~as shown in figure 7) and
helps to ensure that the roped section 46 is in a
position directly overlying the clamp 30. The clamp 30
in open position is then elevated so that the rope
portion 46 is received between the two arms 31 and 33
- Isee figure 3) of the clamp and the clamp is then closed
via the mechanism 34 to securely hold the roped portion
46 of the web 50 as shown in figures 8 to 13 and 1 and 2.
With the roped section 46 retained in the clamp
30 and positioned in overlying relationship to the anvil
26; the sacuring mechanism 40 is moved to advanced
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position as shown in figure 11 to secure the roped section
46 to previously wrapped layer or layers of the web 50,
normally to a previously wrapped roped layer. It will be
noted that the anvil member 26 is cut away in the cen-ter
as generally indicated at 60 as best shown in figure 3
to provide clearance for -the securing mechanism 40 i.e.
lf a stapler is used as is intended with the present
invention, the anvil prevents the ends of the staple from
penetrating the pallet and yet provides a' solid member
against which the webing or other wrapping material may
be forced during stapling. The thickness of the anvil
26 and the cut away portion 60 provide clearance for
the staples to extend through the web 50 and secure the
roped portion 46 thereto.
After the stapling or securing operation, the
shear 38 is advanced and cuts the web between the securing
; staple 66 and the clamp 30 the clamp is spaced sufficiently
- far from the anvil 26 so that the shear 38 may cut-off
the roped section 46 without damaging the underlying layers
of the web 50 and provide a pair of cut ends 62 and 64
~see figures 12 & 13j.
The anvil member 26 is now retracted by drawing
same downwardly as indicated in figure 13 and then the
guide 20 moved to its initial position i.e. retracted
out toward the periphery of the platorm 12 in a position
to permit the next- pallet 52 to be placed on the platform
12 and the roped end 46 is held within the clamp 30 as
shown in figures 1 and 2 and is ready to be moved into
operative position when the anvil 26 is moved into
position contacting the next pallet 52 positioned on the
platform 12.
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The sequence of operation of the various operating
elements may be controlled in the well known manner by a
suitable control mechansim activated by appropriately
located sensors or activators.
~ Iaving described the invention, modi~ications will
be evident to those skilled in the art without departing
rom the spirit of the invention as defined in the
appended claims.
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