Container liner

The present invention relates to a disposable liner comprised of a thin sheet plastics material formed into a long tube having left and right sides and a top and bottom. The tube is closed at each end by end panels formed by folded end flaps of the tube. One end panel has located therein an inlet port and an outlet port formed of reinforced plastics sheet material in the form of tubes attached to the panel. Each port surrounds an aperture in the panel. Upper hook fasteners are located at least at the left and right top corners of the liner at both ends thereof and a lower fastener is located along the bottom edge of the liner at one end thereof. The interior surface of the end panel of the liner opposite the inlet port is protected with a flap made of reinforced plastics material.

The present invention relates to disposable liners for use with rigid 
containers, as for example, the box structure of a truck vehicle, a 
seagoing vessel or other container. 
In particular, the liner according to the present invention is adapted to 
be pneumatically filled with a flowable material. It is contemplated that 
such a liner would be used once and then discarded. As a result, it is 
necessary to provide a liner which is strong and free of rupture but which 
is inexpensive and simple to use. 
In accordance with the present invention there is provided a disposable 
liner for use with a rigid container adapted to be pneumatically filled 
with a flowable material, said liner comprising: a tube of thin sheet 
plastics material forming left and right side panels and top and bottom 
panels; front and back end panels being formed by folding and joining end 
flaps of said tube to provide top, bottom and side edges at the junction 
of said top and bottom and left and right side panels with said front and 
back end panels; inlet and outlet ports located in said back end panel, 
said ports being comprised of tubes of reinforced plastics sheet material, 
each attached at one end to said back end panel around an aperture located 
therein; hook attachment means located at least at top corners of said 
liner adjacent the top edge formed by said front and back end panels; 
bottom attachment means located along the bottom edge formed by said front 
end panel; and a reinforcing flap element protecting the inner surface of 
said front end panel, said flap element being attached to said liner along 
the top edge formed by said front end panel.

Referring now to FIGS. 1 and 2, a liner 10 is comprised of an elongated 
tube portion 12 made of a thin plastics material, for example, 
polyethylene. The polyethylene is typically 6 mils thick. One example of 
an acceptable material is "Felcofilm" (trade mark). 
The longitudinal portion of the liner is made from a tube of polyethylene 
and therefore contains no joints. Flaps 13, 15, 17 and 19 are formed in 
the end portions of the tube 12. The left-most set of flaps are shown in 
FIG. 2. An identical set of flaps is present on the right side of tube 12 
as seen in FIG. 1. These flaps are heat-sealed together to form front and 
back end panels 14 and 16. Hook fasteners 18 are provided along the top 
edges of the tube portion 12. Each hook fastener is made from a reinforced 
woven plastics material and is heat-sealed to the tube 12. Each hook 
fastener has an aperture located therethrough for connection to hooks 
located on a rigid structure which holds the liner. Some embodiments of 
the liner according to the present invention contain only two hook 
fasteners located on each side of the tube 12 at the top directly adjacent 
the back end panel 14. 
A nailing strip 20 is heat-sealed along the lower edge of the tube 12 
directly adjacent the back end panel 14. This nailing strip consists of a 
strip of plastics material heat-sealed to the liner and formed into a loop 
which contains a wooden slat 22. This wooden slat 22 can be nailed to the 
bottom of the rigid container for securing the liner within the container. 
Apertures 28 and 30 are formed in back end panel 14. Inlet and outlet ports 
are made by heat-sealing tubes 24 and 26 to flanges 25 and 27 (see FIG. 
2). Flanges 25 and 27 are then heat-sealed around apertures 28 and 30, 
respectively, to the back end panel 14. Inlet and outlet ports 24 and 26 
and flanges 25 and 27 are made from a woven reinforced plastics material. 
One embodiment of the present invention contains flaps 32 and 34 made of 
woven reinforced plastics material heat-sealed to the inner surface of the 
back end panel 14 over the apertures 28 and 30. These flaps are moved out 
of the way during the filling of the liner by virtue of the pneumatic 
pressure. However, when no pressure is exerted, the flaps cover the holes 
28 and 30 and reduce contamination of the product contained within the 
filled liner. When the liner 10 is emptied the lower flap 34 is merely cut 
to allow an exit of the material from outlet port 26. 
It was found that during filling, the flowable material entering port 24 
could be blown directly to the front of the liner 10 to impinge upon the 
front end panel 16. If the material filling the liner is abrasive, its 
contact with the front panel 16 causes failure of that panel. As a result, 
a protective flap 36 is installed at the front end portion of the liner. 
The flap 36 rests against front end panel 16 and is heat-sealed along the 
top edge of tube 12 at 38. The protective flap is made of a reinforced 
woven plastics material. 
FIG. 3 shows the liner 10 installed in a rigid container, for example, the 
box 40 of a truck 42. The liner 10 is designed to completely fill the box 
and is therefore supported on its bottom, sides and end by the box 40. 
Hook fasteners 18 initially hold the liner within the container 40. 
Nailing strip holder 20 containing a wooden slat 22 secures the back lower 
portion of the liner to the rigid container 40. It should be noted that 
these fasteners are primarily used during the initial stages of filling. 
The liner is secured to the rigid container primarily by virtue of the 
flowable material contained within the liner. 
FIG. 4 shows the location of the nailing strip 20 and slat 22 at the front 
end 16, instead of at the back end panel 14. 
FIGS. 5 to 7 show a modified back end panel 14a containing a loading tube 
29, a vent tube 31 and a discharge tube 33 fitted with ties 35 for closing 
them off. The discharge tube 33 is about twice as long as the loading tube 
to facilitate attachment to an unloading device. The discharge tube 33 is 
offset from the centre line, as seen in FIG. 5, to enable discharge to 
take place while one of the rear doors of the box of the truck (in this 
case the lefthand door) is closed to provide added support for the 
bulkheads that will hold the liner in place. Inside the liner behind the 
vent tube 31 there is a sheet of netting 37 secured across the orifice. 
Tubes 29 and 33 have flaps 32 and 34 as before. The vent tube 31 has no 
flap. 
Reinforcing flanges 39 and 41 are similar to the flanges 25, 27 in that 
they are made of a woven reinforced plastics material. However the flanges 
39 and 41 are located on the outside surface of the back end panel 14a in 
order to protect such panel against abrasion by the bulkheads and doors 
(not shown) at the rear of the truck 42. The flange 39 is rectangular and 
extends between and slightly beyond the tubes 29 and 31. The flange 41 is 
trapezoidal, conforming its shape comparatively closely to the lower flap 
19 of the panel 14a.