[0001] This invention relates to a freight container. Such containers are conventionally
of generally cuboidal shape and have standard external dimensions so that they can
fit in standard spaces on road, rail or sea transport vessels.
[0002] Such freight containers are delivered full of goods to the recipient of those goods.
In a number of situations, those goods are not all unloaded at once, and the container
remains on site and is used as a temporary static storage location.
[0003] Some such containers are refrigerated and contain goods which have to be held below
a certain temperature. In this case, the container itself includes a refrigeration
plant which will require connection to an external power supply.
[0004] According to the present invention, there is provided a rectangular freight container
having length width and height dimensions of a standard size, and two doors at one
end, the doors being of the same height but with different width dimensions and extending
to the floor of the container.
[0005] Making the doors of different sizes means that one door can be large enough to allow
access into the container with trolleys or vehicles larger than would be possible
with a single door.
[0006] The larger door preferably has a lock which can be unlocked by operating a single
lock handle. This makes it easy for the door to be opened and closed which is a particular
requirement where a container is being used as a temporary storage facility from which
goods will be unloaded from time to time and where the access door has to be repeatedly
opened and closed. This is especially the case with refrigerated containers which
may be used for example by supermarkets to hold stock until it is needed to replenish
store shelves.
[0007] In a suitable embodiment, the lock can be a vertical locking bar mounted for rotation
about its own axis adjacent the opening edge of the door, with keepers at the top
and bottom of the door frame to receive locking tongues on the bar, and a lock handle
between the ends of the bar which can be turned to rotate the bar to free the tongues
from the keepers.
[0008] Preferably the smaller door has locks which can only be operated from inside the
container. The smaller door will generally only need to be opened when all the contents
of the container are being loaded or unloaded at once, and can be left closed and
locked when the larger door is opened and close for routine visits to and from the
container. The locks for the smaller door can be shoot bolts at the top and bottom
corners of the inside face of the door.
[0009] The larger door preferably has an internal door release mechanism, so that if the
door is shut with somebody inside the container, they will be able to open the door
to release themselves. The internal door release mechanism can act from inside the
container on an external door release mechanism which will normally be the same lock
mechanism which opens the door from outside.
[0010] A security bar can be locked between the two doors to prevent operation of the single
lock handle. There is a requirement for a secure lock (and a customs seal) to be available
to prevent unauthorised tampering with the container contents. The security bar can
be locked across the single lock handle, so that the lock handle cannot be operated
until the security bar is removed.
[0011] When the container is used for storage purposes, and the main door has to be regularly
opened and closed, it is important that the door fits properly into its frame, especially
where the container is a refrigerated container. To ensure that the frame is not distorted
if the container is resting on uneven ground, the door frame is preferably reinforce
to prevent any skewing.
[0012] The invention will now be further described, by way of example, with reference to
the accompanying drawings, in which:
- Figure 1
- is a partial perspective view of a freight container in accordance with the prior
art;
- Figure 2
- is a rear view of a freight container in accordance with the invention;
- Figure 3
- is a section through the container of Figure 2 on the lines A-A;
- Figure 4
- is a view, on a larger scale, of part of the section from Figure 3, showing a door
open;
- Figure 5
- is a detail of the door locking mechanism, shown in section;
- Figure 6
- shows another view of another part of the locking mechanism; and
- Figure 7
- shows a detail of the door seals.
[0013] Figure 1 shows a conventional storage container 10 which, as is known, has standard
rectangular dimensions, closed sides 16, a closed roof 14 and a floor, and two ends.
At one end there are two doors 18, 20. The doors are hinged to the container frame
at 22 and each door has two locking bolts 24 which can be released using operating
bars 26 to allow the doors to be opened and closed.
[0014] Figure 2 shows a corresponding view of one end of a container in accordance with
the invention. This container has a primary door 124 and a secondary door 125 of smaller
dimensions. Both doors have hinges 122 by which they are hinged to a frame 101. The
secondary door 125 is closed by internal shoot bolts 128 which are operated from inside
the container, such that when both doors are closed there is no accessible mechanism
for opening the secondary door 125.
[0015] The primary door 124 has a single latch mechanism at 130. This latch mechanism operates
a vertical bar 132. The ends of the bar are held in keepers 134 on the frame 101 when
the door is closed and latched. When the latch 130 is released (by operating a handle
142), the bar 132 can be rotated about its own axis to release its end portions from
the keepers 134, so that the door can be opened.
[0016] This latch mechanism may require a key to unlock it before the handle can be moved.
A keyhole 162 can be seen in Figure 6. The latch can however be closed without being
locked, so that access by authorised personnel is not inhibited. It may also be possible
to apply a separate padlock to the latch mechanism.
[0017] Figure 3, which is a section on the lines A-A from Figure 2 also shows flexible seals
136 between the outer edges of the doors 124, 125 and the frame 110, and further seals
138 where the doors 124, 125 meet one another. It can also be seen from Figures 3
and 4 that the latch 130 has a part which extends through the thickness of the door
to an unlatching member 140 on the inside surface of the primary door 124. This mechanism
is shown in more detail in Figure 5, where the main door handle accessible from outside
the container is shown at 142, shielded within a housing 144.
[0018] The internal release knob 140 is mounted at the top of a stem 146 which projects
through a recess in the door and has an opposite end which abuts against the main
door unlatching handle 142. The shaft 146 projects through a saucer recess 148 on
the inside of the door, and when the knob 140 is pushed fully home to the floor of
the recess 148, the pressure of the stem acting on the handle 142 will rotate the
handle far enough to release the upper and lower ends of the bar 132 from their keepers
134, so that the door can be opened from inside.
[0019] Figure 5 shows a security bar 150 which is hinged to the primary door 124 at 152,
extends across the housing 144, and is then retained in a socket 154 on the secondary
door 125. A padlock and/or customs seal can be applied to the socket 154 to prevent
the security bar 150 from being removed. Whilst in place, the security bar 150 prevents
the main door handle 142 from being moved to an unlocking position.
[0020] The primary door 124 also has a keeper 156 (see Figure 2) into which the security
bar 150 can be located once it is safe for the container door to be held closed just
by the lock 130.
[0021] Figure 7 shows a detail of the way in which the doors seal against one another. At
the outer edges of the doors, extrusions 168a and 168b are mounted, and the extrusion
168b on the primary door carries an outer gasket 166 made of EPDM. The form of the
extrusions 168 are such that the edge of the primary door 124 is staggered relative
to the secondary door 125 which allows the primary door to be easily opened and closed.
Secondary lip seals 164a and 164b are mounted in identical extrusions 170a and 170b
on the container interior side of the seal 166.
[0022] The use of a single latch 130 makes it much easier for the primary door 124 to be
opened and closed than is the case with a conventional container door locking arrangement.
This allows the container to be used at its destination as a storage location, where
personnel need and can obtain frequent access to the contents of the container. The
door can easily be opened and closed without complication and without requiring undue
strength. To ensure that the door can always be opened, and to ensure that the seals
136, 138 make effective sealing contact between the door and the frame, the frame
is reinforced compared to standard freight containers. Additional strengthening will
be built in on all four sides of the frame, so that the frame resists skewing which
might otherwise arise should the container be set down on uneven ground, and which
might hamper opening and closing of the doors.
[0023] Furthermore, because the primary door 124 is wide, trolleys or barrows can be brought
into the container to unload its contents.
[0024] The invention is especially useful on refrigerated containers, where it is important
to ensure that the door is not left open.
1. A rectangular freight container having length width and height dimensions of a standard
size, and two doors at one end, the doors being of the same height but with different
width dimensions and extending to the floor of the container.
2. A container as claimed in Claim 1, wherein the larger door has a lock which can be
unlocked by operating a single lock handle.
3. A container as claimed in Claim 2, wherein the lock comprises a vertical locking bar
mounted for rotation about its own axis adjacent the opening edge of the door, keepers
at the top and bottom of the door frame to receive locking tongues on the bar, and
a lock handle between the ends of the bar which can be turned to rotate the bar to
free the tongues from the keepers.
4. A container as claimed in any preceding claim, wherein the smaller door has locks
which can only be operated from inside the container.
5. A container as claimed in Claim 4, wherein the locks for the smaller door are shoot
bolts at the top and bottom corners of the inside face of the door.
6. A container as claimed in any preceding claim, wherein the larger door has an internal
door release mechanism.
7. A container as claimed in Claim 6, wherein the internal door release mechanism acts
from inside the container on an external door release mechanism.
8. A container as claimed in any one of Claims 2 to 7, wherein a security bar can be
locked between the two doors to prevent operation of the single lock handle.
9. A container as claimed in Claim 8, wherein a customs seal can be applied to the security
bar.
10. A container as claimed in any preceding claim, wherein the end face of the container
has a door frame which is reinforced to prevent skewing of the frame if it is resting
on uneven ground.
11. A container as claimed in any preceding claim, which is a refrigerated container.
12. A container as claimed in any preceding claim, wherein the doors extend the full height
of the container so that when both doors are opened, that end of the container is
unobstructed to allow loading of the container.