GB2224301A

GB2224301A - A cistern with cover and seal

Info

Publication number: GB2224301A
Application number: GB8822064A
Authority: GB
Inventors: Brian Cookson
Original assignee: Tanks and Drums Ltd
Current assignee: Tanks and Drums Ltd
Priority date: 1988-09-20
Filing date: 1988-09-20
Publication date: 1990-05-02
Also published as: GB8822064D0

Abstract

A cistern (1, fig 1) for the safe storage of drinking water and which satisfies the requirements of the Water Research Council's Byelaw 30 comprises a container 2, a cover 8, a gasket 6 fitted therebetween, and a plurality of clips 12 for sealably securing the cover 8 to the container 2. The container 2 comprises an outwardly extending flange 4 onto which the gasket 6 is fitted, whilst the cover 8 comprises a downwardly projecting skirt 10 extending around the periphery of the cover 8, and onto which the outer edge of the flange 4 abuts. The clips 12 are capable of exerting a clamping force between the upper face of the cover 8 and the lower face of the flange 4. <IMAGE>

Description

A CISTERN This invention relates to cisterns for the safe storage of drinking water.

Cisterns for domestic use are well known. Such cisterns have a capacity usually in the range 50 to 500 litres. A recent byelaw issued by the Water Research Council - Byelaw 30 - requires that domestic drinking water cisterns do not admit particles larger than roughly 0.65 mm in diameter.

It has been proposed to provide a cistern with a cover secured to the container by means of bolts passing through the cover and secured to the container, there being a gasket between the cover and the container. The fitting of such bolts is time consuming, and it is difficult to assess whether the bolts have been tightened to the correct torque.

According to the present invention, there is provided a cistern comprising a container having a base and side wall means, a cover, a gasket for fitting between the cover and the side wall means, and a clip means for sealably securing the cover to the container.

Preferably, the container comprises an outwardly extending flange for supporting the gasket. The cover may comprise location means projecting downwardly from the cover, preferably at its periphery.

Preferably, the location means comprises a skirt projecting downwardly from the periphery of the cover, and extending around the flange when the cistern is assembled.

Preferably, when the cistern is assembled, the flange lies substantially adjacent -the skirt. Preferably also, when the cistern is assembled, the skirt extends below the flange to prevent removal or fitting of the clip means by a sliding motion in a direction substantially in the plane of the cover.

Preferably, the clip means comprises a plurality of clips. Preferably each clip has a first limb, a second limb extending from the first limb which is substantially perpendicular thereto, and a third limb extending from the second limb which is at an acute angle to both the first and second limbs and the free end region of which is crimped so as to form an arcuate portion which faces towards the first limb, and wherein each one of the clips is capable of clamping the cover to the container, with the gasket fitted therebetween, the first limb of the clip lying against the upper face of the cover, and the arcuate portion of the third limb being in contact with the lower face of the flange. Preferably, each clip is made from a resilient material.

A preferred embodiment of a cistern is now described by way of example with reference to the accompanying drawings, in which: FIGURE 1 is a perspective view of a complete cistern with a cover clipped in place, FIGURE 2 is a partial section through the cistern of Figure 1 showing a detailed view of a clip fitted in place, and FIGURE 3 is a perspective view of the clip.

Figure 1 shows a general view of a cistern 1 wherein a box-shaped container 2, which in this embodiment is made of galvanized steel, comprises a flange 4 which extends outwardly from an upper edge of the container 2, as shown in Figure 2, to form a lip which extends completely around side walls of the container 2.

A gasket 6, which is made of a Water Research Council approved material such as certain grades of rubber and is shaped so as substantially to cover the flange 4, may either be affixed to the flange or rest thereon. A cover 8, in this embodiment made of galvanized steel, comprises a downwardly projecting skirt 10 which extends around the periphery of the cover 8.

Figure 3 shows a general view of a clip 12 made of rust-proof spring steel, a number of which are provided to be disposed around the cover 8 in a manner such as that shown in Figure 1, although it will be appreciated that other configurations are possible. The clip 12 comprises first, second and third limbs, 14, 16 and 18 respectively, disposed relative to each other as shown in Figure 3. A free end region of the third limb 18 is crimped so as to form an arcuate portion 20 which faces towards the first limb 14. The clip 12 is so proportioned as to be capable of exerting a clamping force between the upper face of the cover 8 and the lower face of the flange 4, with the gasket 6 fitted therebetween, as shown in Figure 2.

A number of fitments 22, designed to conform to Byelaw 30, may be provided with the cistern 1, such as vents, input and output pipes and so on.

The container 2 is closed by placing the cover 8 over the flange 4 of the container 2, with the gasket 6 fitted therebetween, and by fitting the clips 12 onto the cistern 1 in the manner described below. The container 2, flange 4, cover 8 and skirt 10 are proportioned relative to each other and relative to the thickness of the gasket 6 such that, when assembled, the skirt 10 surrounds the outer edge of, and extends below, the flange 4. In this way, accidental removal of the clips 12 is prevented since the skirt 10 presents an obstruction to the third limb 18 of the clip 12. The flange 4 lies adjacent the skirt 10, and thereby prevents the third limb 18 from slipping between the flange 4 and the skirt 10.

Each clip 12 is fitted into position on the cistern 1 orientated with its first limb 14 above its third limb 18 but at an acute angle to the plane of the cover 8, such that, in the first stage of the fitting procedure, with the arcuate portion 20 abutting the lower face of the flange 4, the clearance between the first limb 14 and the upper face of the cover 8 is greatest at the free end of that limb. In the second stage of the fitting procedure, the clip 12 is rotated to a position where the first limb 14 lies against the upper face of the cover 8. Removal of the clip 12 is the reverse of fitting.

It will of course be understood that the present invention has been described purely by way of example, and modifications of detail can be made within the scope of this invention.

Claims

1. A cistern comprising a container having a base and side wall means, a cover, a gasket for fitting between the cover and the side wall means, and a clip means for sealably securing the cover to the container.

2. A cistern according to Claim 1 wherein the container comprises an outwardly extending flange for supporting the gasket.

3. A cistern according to Claim 1 or Claim 2 wherein the cover comprises location means projecting downwardly from the cover.

4. A cistern according to Claim 3 as dependent on Claim 2 wherein the location means comprises a skirt projecting downwardly from the periphery of the cover, and extending around the flange when the cistern is assembled.

5. A cistern according to Claim 4 wherein, when the cistern is assembled, the flange lies substantially adjacent the skirt.

6. A cistern according to Claim 4 or Claim 5 wherein, when the cistern is assembled, the skirt extends below the flange to prevent removal or fitting of the clip means by a sliding motion in a direction substantially in the plane of the cover.

7. A cistern according to any one of the preceding claims wherein the clip means comprises a plurality of clips.

8. A cistern according to Claim 7 wherein each clip has a first limb, a second limb extending from the first limb which is substantially perpendicular thereto, and a third limb extending from the second limb which is at an acute angle to both the first and second limbs and the free end region of which is crimped so as to form an arcuate portion which faces towards the first limb, and wherein each one of the clips is capable of clamping the cover to the container, with the gasket fitted therebetween, the first limb of the clip lying against the upper face of the cover, and the arcuate portion of the third limb being in contact with the lower face of the flange.

9. A cistern according to Claim 8 wherein each clip is made from a resilient material.

10. A cistern substantially as herein described with reference to the accompanying drawings.