Note: Descriptions are shown in the official language in which they were submitted.
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The present invention relates to packaging and
more particularly, relates to a stretch wrapping
machine.
The use of stretch wrapping machines is well
known in the art and thus, for example, reference may
be had to U.S. Patent ~,735,033 which discloses such
an arrangement.
In the stretch wrapping machines, a stretched
web or layer of film is utili%ed to cover and contain
a load. Such an arrangement may be utilized, for
example, to contain and protect articles loaded on a
pallet or to cover and protect even a single article.
There are several different ways of applying the
film or web of material to the material to be
wrapped. Thus, for example, in one smbodiment, the
load itself may be rotated while the supply of film
may remain static in the sense of the circular
motion. Alternatively, the load may remain static
and the film itself may be rotated about the articles
to be wrapped. Still further, combinations of the
above method may be utilized and still further,
different motions may be combined. For example, it
is conventional that the means mounting the film will
move in a linear fashion (normally vertical) while
the ~ilm is being applied irrespective of whether it
is the film supply means or the load which is
rotated.
In the art, the drive means for rotational
movement of the film supply means and/or the load are
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provided by conventional drives i.e. electric motors.
Since most loads to be wrapped are of a substankial
weight, the drive means must be relatively rugged and
usually electric motors with chain drives are
utilized. The mechanical arrangement of such drives
is well known in the art and the design thereof is
subject to normal limitations such as limited speed
of rotation due to inertia) problems with braking,
mechanical malfunctions, lubrication of the chain
drive, etc.
It is an object of the present invention to
provide a stretch wrapping apparatus which overcomes
the problems of the prior art by utilizing different
drive means which provide a more efficient
arrangement.
According to one embodiment of the present
invention, there is provided a stretch wrapping
apparatus which has a linear drive motor as the drive
means to rotatably drive the load. In particular, in
this embodiment, there is prcvided a stretch wrapping
apparatus which includes a frame having at least one
upwardly extending member. Secured to said upwardly
extending frame member is a film supply mounting
means. The film supply mounting means carries a
supply of film and may conveniently include a pair of
rollers through which the film is dispenses in a
conventional manner. Drive means are provided for
recriprocally driving the film supply mounting means
along the vertically extending frame member. A load
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receiving platform is provided; the platform is
adapted to be rotatably driv~n. To this end, the
platform includes induction strip means formed in a
circular configuration. Associated with the
induction strip means, and fixedly mounted is a
linear drive motor which, in conjunction with the
induction strip means, are such that when the motor
is operated, the platform and induction strip means
will be rotatably driven.
In a further embodiment of the invPntion, the
stretch wrapping apparatus includes a frame which is
disposed such that the frame at least partially
surrounds the load to be wrapped. In particular, the
frame has a horizontal frame member which extends
over the load to be wrapped. Secured to the
horizontal frame member is a horizontally extending
arm. The horizontally extending arm is mounted to
the frame so as to be rotatable. At one end of the
horizontally extending arm there is provided a
vertical downwardly extending arm. This vertically
extending arm carries the film supply support means.
The film supply support means is moveable in a
reciprocal fashion along the vertically extending
member and suitable drive means are provided for this
purpose. The horizontally extending arm has
associated therewith induction strip means which are
formed in a generally circular configuration. A
linear drive motor is mounted on the frame in a fixed
manner and in operative relationship to the inductive
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strip means, such that, upon operation of the motor,
the horizontally extending arm will be driven in a
rotatable manner.
According to a third ambodiment of the present
invention, there is provided a stretch wrapping
apparatus which includes film supply mounting means
which are mounted on a structural member, the
structural member having associated therewith
induction strip means. A linear drive motor is
mounted on a suitable member such as a frame member
in operative relationship to the induction strip
means such that upon operation of the linear motor,
the film supply mounting means will be driven in the
desired path.
In the first embodiment, as above described, the
load is mounted upon a turntable which is rotatably
driven. The turntable is preferably constructed to
minimize the friction between the support and the
turntable and to this end, suitable means such as
ring bearings may be utilized. The rotational force
is supplied by the action of the linear motor on the
induction strip means. In this embodiment, as in the
other embodiments, the induction strip means may form
a separate means attached to the turntable or in the
alternative, the turntable may be manufactured such
that the induction strip means are an integral part
thereof.
Preferably, the film supply mounting means are
mounted on a member which forms a portion of the
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frame. It will, of course, be understood that they
may be mounted on any other suitable means if so
desired. The film supply and the dispensing thereof
is a conventional arrangement and need not be
discussed in greater detail herein. It suffices to
say that the use of conventional feed rolls, wiper
means and the like may be utilized in the practice of
the invention.
In the second embodiment of the invention
wherein a horizontal member having a downwardly
extending arm is rotated about the load to be wrapped
and similar to the first embodiment, conventional
film dispensing means may be employed.
In the third embodiment described above, the
device may be utilized in either the vertical or
horizontal mode. Thus, there are known arrangements
wherein a load may be transferred through the drum or
other member on which the film dispensing means are
mounted. In such an arrangement, means may be
employed for advancing the load through the drum at
a speed such as to permit continuous wrapping of the
load.
Alternatively, the device may be oriented such
that it wraps the load while in a vertical mode. In
such an arrangement, the load and wrapping means may
be moved relative to one another to ~over a larger
area.
Still further, the arrangement may be such that
the film dispensing means are mounted on a track
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wherein the film dispensing means will follow a
preset path. This path may be designed such as to
permit the film to travel in a linear direction while
rotating about the load - i.e. a spiral
configuration. Naturally, in such a configuration,
the path the film dispensing means follows can be a
non circular path. This is highly advantageous in
wrapping unusually shaped loads.
Having thus generally describ~d the invention,
reference will be made to the accompanying drawings
illustrating embodiments thereof, in which:
Figure 1 is a perspective view of a first
embodiment of a stretch wrapping apparatus according
to the present invention;
Figure 2 is a perspective view of a second
embodiment of a stretch wrapping apparatus; and
Figure 3 is a perspective view of a third
embodiment of a stretch wrapping apparatus according
to the teachings of the invention.
Referring to the drawings in greater detail and
by reference characters thereto, there is illustrated
a stretch wrapping apparatus 10 which includes a pair
of parallel bottom frame members 12 and 14.
Interconnecting frame members 12 and 14 are shorter
frame members 18 and 20 as may be seen in Figure 1.
Frame members 12, 14, 18 and 20 may be formed in a
conventional manner and thus, as illustrated are of a
tubular metallic material secured together by
suitable means - e.g. welding. Together, they form a
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somewhat rectangularly configurated bottom portion.
Secured to frame member 18 is a plate 24 which
in turn, is secured to a vertically ext~nding frame
member 22. Member 22 comprises an I-beam which is
adapted ko hold the film dispensing means as will be
discussed in greater detail hereinbelow.
A roll of film 26 which is to be wrapped about
the load to be packaged is mounted on a film support
means generally designated by reference numeral 16.
Film support means 16 includes a pair of rQllers 28
through which the film is dispenses. A conventional
drive means 30 is provided for moving film support
means 16 in a vertical direction such that as the
film is dispensed through rollers 28, the film may be
moved in a vertical direction upwards or downwards to
cover the entire load to be stretch wrapped. Drive
means 30 are conventional and need not be discussed
in detail as they are well known in the art.
A load support platform 32 is mounted on frame
member 20 and is adapted to receive the article or
articles constituting the load to be stretch wrapped.
Typically, platform 32 would be designed to receive a
pallet of articles which may be transported into
position on khe platform.
The weight of the units on platform 32 is
supported through a plurality of support members 34
which support a ring member 36 to permit rokation of
platform 32. Suitable bearings are provided to
minimize the friction to permit easy turning of
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platform 32.
Mounted on the underside of platform 32 is strip
inductive member 42. Strip inductive member 42
operates in cooperation with a linear drive motor 38
which is mounted by means of supports 40 to frame
member 14.
As may be seenl linear motor 38 is thus able to
rotatably drive platform 32 while film support means
16 may move in a vertical direction to completely
wrap the articles placed on platform 42. Preferably,
the arrangement is such that means are provided so as
to maintain a constant gap between linear motor 38
and inductive strip 42 so as to maximize the
efficiency of the drive means.
In a further embodiment of the invention, the
article or articles to be wrapped remain stationary
while the film supply means rotate. Such an
embodiment is illustrated in Figure 2 and reference
will now be made thereto.
In this embodiment, the stretch wrapping
apparatus generally designed by reference numeral 60
includes a pair of vertical frame members 62 and 64
with a horizontal frame member 66 extending between
the upper ends thereof. In this embodiment, the
article or articles to be wrapped are generally
located between vertical frame members 62 and 64.
A film support means designed bv reference
numeral 71 carries a roll of film 68 which is
dispensed between a pair of rollers 70 in the manner
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previously described. A drive means 72 is adapted to
move film support means 71 vertically on a vertically
extending I-beam member 7~ in a manner similar to
that described with respect to the embodiment of
Figure 1~
Member 7B is secured, at its upper end, to a
horizontal member 76 which, in turn, is rotatably
mounted to horizontal frame member 66 through a
bushing 84. Thus, horizontal member 76 may be
rotated about bushing 84 to carry vertical member 78
to substantially encircle a load placed between frame
members 52 and 64.
Secured to horizontal arm 76 is a ring member 80
which includes an inductive strip 82 on its supper
side. A linear motor 74 is mounted on horizontal
frame member 66 in a manner to operate in cooperation
with induction strip 82. Thus, as may be seen,
operation of linear motor 74, in conjunction with
conductive strip 82, will cause horizontal arm 76 to
rotate above point 84 and to thereby enable the film
to encircle the item or items to be packaged. As
previously discussed, film support means 71 can also
move in a vertical direction to permit full wrapping
of the articles.
Re.ferring now to the embodiment of Figure 3, the
apparatus 110 includes a frame generally designated
by reference numeral 111. Frame 111 is of a
generallv rectangular configuration and comprised of
a plurality of tubular members arranged in a
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conventional mann~r. Mounted interiorly of frame 111
is a film mounting member 114 which has a ring like
configuration. Member 114 is rotatably mounted
within frame 111 by a suitable means (not shown).
Member 114 has mounted thereto film dispensing means
112 which, in a manner similar to the previously
described embodiments, includes film roll 116 and
rollers 118.
Mounted on the side of member 114 is inductive
strip 120 which acts in cooperation with linear motor
122 which is mounted on frame 111. Thus, in
operation, member 114 will be driven in a rotatable
manner and will carry film dispensing means 112 about
the load to be wrapped.
In conjunction with the operation of the
apparakus shown in Figure 3, means may be provided
for linearly feeding the load to be wrapped through
the interior of ring like member 114. It will he
evident that the apparatus shown in Figure 3 may be
operated wh~rein the load is fed through either
horizontally or vertically depending upon the
orientation of the apparatus.
A further modification to the embodiment of
Figure 3 would include the use of members 114 which
have different configurations. Thus, the path
followed by film dispensing means 112 may be other
than circular if desired for wrapping a load.
Similarly, member 114 may in itself dafine a path
through which it is desired to have the film
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dispensing means 112 followed. Thus, for example,
member 114 may have a spiral like configuration and
the film dispensing means 112 would follow the spiral
path through operation o~ the linear motor 122.
It will be understood that changes and
modifications may be made to the above described
embodiments without departing from the spirit and
scope of the invention.
