GB2060039A - Dry freight container door seal - Google Patents

Abstract

A container door seal is disclosed which is designed to be self retaining and to be forced onto a kinked flange located around the periphery of the container door. The seal has a generally U-shaped flange gripping portion 3 which is provided with a plurality of flange gripping fins 9 on the inner faces of the arms of the U, there being a metallic U-shaped carrier 5 surrounded by elastomeric material forming the flange gripping portion and there being a first or exterior sealing arm 11 projecting from one arm of the U and a second or interior sealing portion 13 projecting from the opposite arm of the U, the first arm forming a seal with the exterior of the container door frame and the second sealing portion forming a seal with an interior face 15 of a frame. A subsidiary sealing portion 19 may also be provided, and a seal support 17. <IMAGE>

Description

SPECIFICATION Dry freight container door seal This invention relates to a dry freight container door seal.

As is well known, it is now more and more common to transport goods in freight containers and traditionally, the doors of such containers are provided with elastomeric seals around their periphery to seal off the inside of the container from the exterior. It is desirable that these seals be entirely moisture and air proof especially if the containers are to be used for transporting produce and it is also important that the seals be tamper proof. In other words, when the container door is closed, it should be impossible for the seals to be removed to gain access to the interior of the container without the door being opened.

Traditionally, cargo containers are stacked vertically, and it is therefore also important that the door seal does not project substantially outwardly of the face of the container door so as to allow vertical stacking or racking of the containers without interference.

Traditionally, container door seals are fitted to the doors either by means of an adhesive or with the aid of rivets, screws or other fixing devices.

Such seals operate perfectly satisfactorily, but unfortunately, it is a time consuming job to fit the seals and especially to replace them. This problem has been partially overcome by means of the seals the subject of our U.K. Patent No. 1553281 or subject to our pending U.K. Patent application No.

19990/77 which seals are of two parts. They are however obviously expensive to manufacture.

The present invention seeks to provide a container door seal which overcomes the problems associated with known container door seals.

According to the present invention we provide a seal for fitting to a flange formed on a door of a cargo container and comprising a generally U-shaped flange gripping portion incorporating a stiff U-shaped carrier surrounded by elastomeric material which portion is designed to grip and overlie the free end portion of the flange and be self retaining, there being a first sealing portion in the form of a curved arm projecting from one arm of the U to provide an external seal with the door frame of the cargo container and a second sealing portion projecting from the other arm of the U to provide an internal wiping seal with an internal face of the door frame.

Preferably, a subsidiary sealing portion projects from one of the arms of the U to provide a moisture seal in the vicinity of the flange, i.e. to prevent passage of water which may have seeped around the flange. This subsidiary seal may however not be necessary if the U-shaped flange gripping portion is provided with gripper fins, especially if they are of the construction shown in one of our U.K. Patents 1,456,086, 1 509770, or in our U.K. Patent Application No. 45835/75.

Preferably, the second sealing portion is also in the form of a curved arm which bears against an edge face of the door frame when the door is closed. If desired, a seal support may project from this arm to assist in biasing the end portion of the arm into engagement with said end face.

Also according to the present invention, we provide a cargo container having at least one door surrounded by door frame members or partly by another door, said at least one door having a sealing flange adjacent its external periphery which is preferably kinked so that its free end portion faces in the shutting direction of the door, there being a seal supported on said flange, the seal having a generally U-shaped flange gripping portion incorporating a stiff U-shaped carrier surrounded by elastomeric material overlying the free end portion of the flange and being selfretaining thereon, there being a first sealing portion in the form of a curved arm projecting from an external arm of the U-shaped flange and arranged, when the door is shut, to bear against an exterior face of the door frame of the container forming a seal therewith, and there being a second sealing portion projecting from the other or interior arm of the U and providing, when the door is shut, a seal with the internal face of the door frame, the arrangement being such that as the door is closed, so the edge portion of the second sealing portion will wipe against said internal face of the door frame.

A container door sealing in accordance with the present invention is now described by way of example with reference to the accompanying drawing which is a cross section through the seal.

Referring to the drawing, a door of a cargo container is shown in outline at D, there being a flange for a door seal attached to the periphery of the door this flange being shown at S and having its free end portion kinked inwardly in the shutting direction of the door. The opening or frame around the door of the cargo container is shown in outline at F.

The door seal is shown at 1 and has a generally U-shaped flange gripping portion 3 incorporating a stiff carrier 5 again of U-shaped construction and traditionally made of the Schlegel wire which is bent into a zig-zag configuration and is held in that position by rows of thread knitted into the zigzags. The wire carrier is encapsulated or surrounded by an elastomeric material 7, the two arms of the U having on their internal faces a plurality of flange gripping fins 9 running longitudinally of the seal. It is preferred there be one large gripper fin on one of the arms of the U and three small more easily deformable gripper fins on the other arm of the U, the small fins being designed to seal against the exterior face of the flange S as shown in the drawings.With this construction, so long as the flange gripping portion 1 is of approximately the right size for the flange S, the portion 1 will form a satisfactory grip when pushed on to the flange, regardless of manufacturing tolerances in the width of the flange S.

Projecting from one of the arms of the Ushaped flange gripping portion is a first sealing portion 11 in the form of an arm curved inwardly such that when the seal is fitted to the flange S and the door is closed, the free end portion of the arm 11 will abut the door frame F and be deformed outwardly, its natural resiliency thus forming an external seal with the frame F.

Projecting from the opposite arm of the flange gripping portion is a second seal portion 13 which is again in the form of a curved arm, the curve being more pronounced so that the free end portion of the arm forms an angle of about 1000 with its root portion. In use, this free end portion of the second sealing arm 13 will be bent over in a clockwise direction as the container door is shut and the free end portion abuts an internal face 1 5 of door frame F, the bent over portion then wiping against the internal face 1 5 and being biased against the face by the natural resiliency of the portion 13 so as to form an internal seal with the face. If desired, a seal support 17 may be formed integral with the arm 13, the tip of the support 17 bearing against the internal face of the door D to reduce the amount by which the second sealing portion 13 collapses when the door is closed.

A subsidiary sealing portion 19 also projects from the other arm of the flange gripping portion 3 to provide a secondary seal with the door in the event that moisture may seep around the gripper fins 9 when the seal is secured to the door.

Obviously, it is undesirable that any such moisture should reach the interior of the container and this subsidiary sealing portion 19 is designed to prevent the further passage of such moisture towards the interior of the container within the gap between the internal face of the door D and the internal face 15 of the door frame F. The subsidiary sealing portion 19 could be of other constructions to that shown for example it could be a bulbous nature. It is also envisaged that the second sealing portion 13 could be of a bulbous construction.

Although the illustrated seal is shown as being of all one elastomeric material, it could be formed of two or more different hardnesses of material.

Because the seal incorporates the wire carrier 5, it is normally formed on a cross head extruder but two or more extruders could be incorporated in the machine so as for example to make the gripper fins 9 of a softer material from the remainder of the seal or one or more of the sealing portions 11, 13 or 19 could again be of a different material.

It will also be appreciated that the shape and configuration of the gripperfins 9 may be altered and it is even envisaged that in some circumstances they could be omitted or replaced by some other sealing device which also forms a self retaining grip on the flange S.

Once the seal of the present invention has been fitted to a container door flange S and the door has been closed, it will be appreciated that it is impossible to remove the seal because the base of the inverted U is in close proximity to the door frame F and hence cannot be forced off the flange.

Furthermore, because the flange is kinked over inwardly, the seal does not project outwardly of the door D at ali and hence it is difficult to damage the flange during handling of the container.

Claims (7)

1. A seal for fitting to a flange formed on a door of a cargo container and comprising a generally Ushaped flange gripping portion incorporating a stiff U-shaped carrier surrounded by elastomeric material which portion is designed to overlie the free end portion of the flange and be self retaining, there being a first sealing portion in the form of a curved arm projecting from one arm of the U to provide an external seal with the door frame of the cargo container and a second sealing portion projecting from the other arm of the U to provide an internal wiping seal with an internal face of the door frame.

2. A cargo container having at least one door surrounded by door frame members or partly by another door, said at least one door having a sealing flange adjacent its external periphery which is preferably kinked so that its free end portion faces in the shutting direction of the door, there being a seal supported on said flange, the seal having a generally U-shaped flange gripping portion incorporating a stiff U-shaped carrier surrounded by elastomeric material overlying the free end portion of the flange and being selfretaining thereon, there being a first sealing portion in the form of a curved arm projecting from an external arm of the U-shaped flange and arranged, when the door is shut, to bear against an exterior face of the door frame of the container forming a seal therewith, and there being a second sealing portion projecting from the other or interior arm of the U and providing, when the door is shut, a seal with the internal face of the door frame, the arrangement being such that as the door is closed, so the edge portion of the second sealing portion will wipe against said internal face of the door frame.

3. The invention as claimed in claim 1 or 2 wherein a subsidiary sealing portion projects from one of the arms of the U to provide a moisture seal in the vicinity of the flange.

4. The invention as claimed in claim 1,2 or 3 wherein gripper fins are provided on the inner faces of the arms of the flange gripping portion, there being one large gripper fin projecting inwardly from one arm towards the base of the U and there being at least two smaller more easily deformable gripper fins projecting inwardly towards the base from the other arm of the U.

5. The invention as claimed in claim 1, 2, 3 or 4 wherein the second sealing portion is also in the form of a curved arm which bears against an edge face of the door frame when the door is closed.

6. The invention as claimed in claim 5 wherein a seal support projects from this arm to assist in biasing the end portion of the arm into engagement with the end face.

7. A container door seal substantially as herein before described with reference to the accompanying drawing.