GB1601697A

GB1601697A - Moulded containers

Info

Publication number: GB1601697A
Application number: GB2824077A
Authority: GB
Original assignee: Lucas Industries Ltd
Current assignee: ZF International UK Ltd
Priority date: 1977-07-06
Filing date: 1977-07-06
Publication date: 1981-11-04
Also published as: FR2396903A1; FR2396903B1; DE2826305A1; DE2826305C2

Description

(54) MOULDED CONTAINERS (71) We, LUCAS INDUSTRIES LIMITED, a British Company of Great King Street, Birmingham B19 2XF, England, do hereby declare the invention for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invetnion relates to containers which may be used for storage or transportation. Such a container has a lid which is sealed against the container body through a flexible seal providing reliable watertight and preferably even hermetic sealing. For an accurate seal however, it is necessary to provide for the mating sealing surfaces to be substantially accurately aligned. If they are not, gaps exist through which dirt and moisture may enter.The seal is housed in a groove in the container body or lid and the other is provided with an edge engaging the seal.

The problems are particularly associated with containers for large and heavy articles which must be reliably protected from damage as well as from water, or water vapour or other adverse environment.

The usual way of providing that the seal is an accurate fit is to provide a separate component for containing the seal and often also another for engagement with the flexible seal, said separate component or components being secured to the lid or to the container body, as appropriate. This arrangement is usually adopted because it is very difficult to form the edge of the lid or container body itself sufficiently accurately. This is particularly the case where the lid and container body are fabricated from materials such as glass reinforced plastics.

The use of a separate component however, though solving the problem of accurate location of the mating sealing surfaces, gives rise to the additional need to seal the component to the container body or lid in a moisture and/or airtight manner.

Also on large containers in particular, resistance to distortion around the seal is important.

The object of the invention is to provide a container having a seal between lid and container body in a simple, effective and accurate form.

According to the invention, a container having a seal between a lid and a container body is characterised in that at least one of the components which are the lid and container body is formed from layers of reinforced plastics material, the component or one of the components formed from said reinforced plastics material having a groove formed in the edge thereof between integral formations thereon formed by respective layers of the material, said groove containing a flexible seal, the other component having an integral edge portion to engage the seal.

It is a further object to provide a method of making a container having an effective and accurate seal between the lid and the container proper.

According to this aspect, the invention provides a method of making a container having a seal between a lid and a container body, at least one of the components which are the lid and container body being formed from a reinforced plastics material, the method comprising making said one component by laying layers of the material into a shaped mould and subsequently inserting a further part to the mould to enclose the edge of the previously layed layers, and then laying further layers of the material over said further part, then removing said further part of the mould, after setting of the material, so that the space occupied thereby defines a groove in the edge of the component for accommodating a flexible seal, the other component being separately formed.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a container partly broken away and constructed in accordance with the invention, but omitting the seal, for clarity; Figure 2 is an enlarged fragmentary crosssection view of the container; Figure 3 is a cross-section view of a mould showing the lid in a partly constructed condition, and Figure 4 shows the mould with the lid in finished condition.

The container illustrated in Figure 1 is formed from glass reinforced plastics material applied in a number of successive layers. The container comprises a container body 10 and a lid 11. These are of square form but it is to be understood that the invention is applicable to containers of any profile such as rectangular, circular or other form. The container body 10 in this example is deeper than the lid and has rounded corners.

The container body 10 has a thickened peripheral edge 17 which is dimensioned to enter the groove 14 containing the seal 15 so that its upper edge rests against the seal 15.

The downwardly depending edge of the lid has two spaced parallel downwardly extending portions 12, 13 defining between them a groove 14 containing a flexible seal 15. The inner portion 12 is longer than the outer portion 13. As seen in Figure 2, the portions 12 and 13 are joined integrally with the remainder of the lid 11 and immediately above the junction of the portions 12 and 13, the peripheral edge of the lid 11 is thickened at 16.

The seal is formed from a flexible material such as rubber or rubber-like plastics material and the edge of the container body 10 compresses this to form a tight moisture and airtight seal between the lid and the container body. Clips or other fastening devices are used to secure the lid 11 to the container body 10 and hinges may also be provided between them. These are, however, not shown in the drawings. In this example, the sealing arrangements are in one plane but in further examples of containers, constructed in this way, the seal and complementary edge of the lid may have portions in different planes, though for moisture and airtight seal, this will be continuous around the container body and lid.

Though illustrated with the seal 15 occupying a groove in the lid, this component may, however be formed on the container body whereas the lid may be provided with the edge shown on the container body in the drawings. The grooved edge provides a high degree of stiffness to such edge to resist deformation. Moreover, the depth of the groove and the different lengths of the portions defining the groove resist any tendency of the edge of the lid to become dislodged from contact with the seal and even to leave the groove, under severe distortion conditions which may be applied either from outside or inside the container.

Figures 3 and 4 illustrates stages in the production of the lid 11. Figure 3 shows the peripheral edge of a mould 18. This is flanged at 19 and has a bend at 20 so as to form on its internal surface a corresponding shape in the form of a sloped shoulder.

The drawing (Figure 3) also shows the peripheral edge of the lid which is formed in this mould. This peripheral edge is identified by numeral 13 since this is the portion formed at this stage. The lid is constructed from reinforced plastics material, preferably glass reinforced plastics material. The process for production of the lid comprises laying up layers of the reinforcement impregnated with liquid or semi-liquid resin material to conform to the mould shape.

A constant thickness layer is thus produced, and the edge of this is shown in Figure 3.

Having layed up the number of layers required to form the desired thickness, a further part is added to the mould. This part rests on and is located by the flange 19 of the mould 18 and comprises a ring 21 of L-shaped cross-section as shown in Figure 4 and an upstanding ring 22 with rounded upper edge. The rings 21 and 22 are secured together and the position of the latter is such that when placed in position as shown in Figure 4, the ring 22 sandwiches the portion 13 of the lid which has been moulded in a state shown in Figure 3. The lower edge of this portion 13 is furthermore confined by the portion of the ring 21 engaging on the flange 19 of the mould 18.

Further layers of the reinforced plastics material are now layed up onto the interior surface of the ring 22 as well as of the adjacent portion of the lid wall. This process produces the portion 12 as well as the thickening 16 at the edge of the lid 11. The lower edge of the portion 12 is confined by a step formed between the rings 21 and 22 since the ring 21 is of smaller internal diameter than the ring 22.

After setting of the material, which may be carried out at ambient or at elevated temperature, the mould and the further part thereof are removed, thus defining a completed lid 11 with groove 14 for containing the seal 15. Next, the seal is fitted. The container body may be formed by a similar though single stage process from the same material, though it is possible to produce this component from a different material.

This arrangement provides for accurate positioning of the seal and the locating groove 14 for it is formed between portions which are integral with the remainder of the lid or container body as appropriate.

WHAT WE CLAIM IS: 1. A container having a seal between a lid and a container body characterised

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. Figure 3 is a cross-section view of a mould showing the lid in a partly constructed condition, and Figure 4 shows the mould with the lid in finished condition. The container illustrated in Figure 1 is formed from glass reinforced plastics material applied in a number of successive layers. The container comprises a container body 10 and a lid 11. These are of square form but it is to be understood that the invention is applicable to containers of any profile such as rectangular, circular or other form. The container body 10 in this example is deeper than the lid and has rounded corners. The container body 10 has a thickened peripheral edge 17 which is dimensioned to enter the groove 14 containing the seal 15 so that its upper edge rests against the seal 15. The downwardly depending edge of the lid has two spaced parallel downwardly extending portions 12, 13 defining between them a groove 14 containing a flexible seal 15. The inner portion 12 is longer than the outer portion 13. As seen in Figure 2, the portions 12 and 13 are joined integrally with the remainder of the lid 11 and immediately above the junction of the portions 12 and 13, the peripheral edge of the lid 11 is thickened at 16. The seal is formed from a flexible material such as rubber or rubber-like plastics material and the edge of the container body 10 compresses this to form a tight moisture and airtight seal between the lid and the container body. Clips or other fastening devices are used to secure the lid 11 to the container body 10 and hinges may also be provided between them. These are, however, not shown in the drawings. In this example, the sealing arrangements are in one plane but in further examples of containers, constructed in this way, the seal and complementary edge of the lid may have portions in different planes, though for moisture and airtight seal, this will be continuous around the container body and lid. Though illustrated with the seal 15 occupying a groove in the lid, this component may, however be formed on the container body whereas the lid may be provided with the edge shown on the container body in the drawings. The grooved edge provides a high degree of stiffness to such edge to resist deformation. Moreover, the depth of the groove and the different lengths of the portions defining the groove resist any tendency of the edge of the lid to become dislodged from contact with the seal and even to leave the groove, under severe distortion conditions which may be applied either from outside or inside the container. Figures 3 and 4 illustrates stages in the production of the lid 11. Figure 3 shows the peripheral edge of a mould 18. This is flanged at 19 and has a bend at 20 so as to form on its internal surface a corresponding shape in the form of a sloped shoulder. The drawing (Figure 3) also shows the peripheral edge of the lid which is formed in this mould. This peripheral edge is identified by numeral 13 since this is the portion formed at this stage. The lid is constructed from reinforced plastics material, preferably glass reinforced plastics material. The process for production of the lid comprises laying up layers of the reinforcement impregnated with liquid or semi-liquid resin material to conform to the mould shape. A constant thickness layer is thus produced, and the edge of this is shown in Figure 3. Having layed up the number of layers required to form the desired thickness, a further part is added to the mould. This part rests on and is located by the flange 19 of the mould 18 and comprises a ring 21 of L-shaped cross-section as shown in Figure 4 and an upstanding ring 22 with rounded upper edge. The rings 21 and 22 are secured together and the position of the latter is such that when placed in position as shown in Figure 4, the ring 22 sandwiches the portion 13 of the lid which has been moulded in a state shown in Figure 3. The lower edge of this portion 13 is furthermore confined by the portion of the ring 21 engaging on the flange 19 of the mould 18. Further layers of the reinforced plastics material are now layed up onto the interior surface of the ring 22 as well as of the adjacent portion of the lid wall. This process produces the portion 12 as well as the thickening 16 at the edge of the lid 11. The lower edge of the portion 12 is confined by a step formed between the rings 21 and 22 since the ring 21 is of smaller internal diameter than the ring 22. After setting of the material, which may be carried out at ambient or at elevated temperature, the mould and the further part thereof are removed, thus defining a completed lid 11 with groove 14 for containing the seal 15. Next, the seal is fitted. The container body may be formed by a similar though single stage process from the same material, though it is possible to produce this component from a different material. This arrangement provides for accurate positioning of the seal and the locating groove 14 for it is formed between portions which are integral with the remainder of the lid or container body as appropriate. WHAT WE CLAIM IS:

1. A container having a seal between a lid and a container body characterised

in that at least one of the components which are the lid and container body is formed from layers of reinforced plastics material, the component or one of the components formed from said reinforced plastics material having a groove formed in the edge thereof between integral formations thereon formed by respective layers of the material, said groove containing a flexible seal, the other component having an integral edge portion to engage the seal.

2. A container as claimed in claim 1 in which the seal is engaged in the groove by a thickened portion of said other component.

3. A method of making a container having a seal between a lid and a container body, at least one of the components which are the lid and container body being formed from a reinforced plastics material, the method comprising making said one component by laying layers of the material into a shaped mould and subsequently inserting a further part to the mould to enclose the edge of the previously layed layers, and then laying further layers of the material over said further part, then removing said further part of the mould, after setting of the material, so that the space occupied thereby defines a groove in the edge of the component for accommodating a flexible seal, the other component being separately formed.

4. A container substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

5. A method of making a container substantially as hereinbefore described with reference to and as shown in the accompanying drawings.