GB2219894A

GB2219894A - Earth seal unit

Info

Publication number: GB2219894A
Application number: GB8814599A
Authority: GB
Inventors: Roger William Peirce
Original assignee: CLEANLINE FABRICATIONS
Current assignee: CLEANLINE FABRICATIONS
Priority date: 1988-06-20
Filing date: 1988-06-20
Publication date: 1989-12-20
Anticipated expiration: 2008-06-20
Also published as: GB8814599D0; GB2219894B

Abstract

An earth seal unit has a housing 8 defining a base 9 and side walls 10. A conduit 24 extends into the housing through the base. The seal 28-35 is provided to effect a substantially water-tight coupling between the end region 23 of the conduit and a conductor rod 36 passing through the conduit into the ground. The earth seal unit has a lid or cover 1 to close the upper part of the housing, and lockable means 5 are provided to lock the cover in the closed position. <IMAGE>

Description

Description of the Invention "Improvements in or relating to an Earth Seal Unit" THIS INVENTION relates to an Earth Seal Unit An earth seal unit is provided frequently when a building is erected. The earth seal unit incorporates a conductive element which makes good electrical contact with the ground beneath the building to provide a ready source of earth potential. This earth conductor terminates in a box which is sealed. The box is sealed to preview ground water rising up XntD the box fro beneath and also to prevent ready access te the earth conductor The earth conductor may be electrically connected to the electrical supply system present in the building, to provide the necessary "earth" ani may also be connected to a lightning conductor.In bui'dinDs fabricated primarily from a metallic framework the earth conductor may also be connected to the metallic fra;:ewor.

In a large building a plurality of earthing conductors may be provided and thus a plurality of earth seal units may be required.

According to this invention there is provided an earth seal unit, said unit comprising a housing defining a base and side walls, a conduit extending up into the housing through the base, means to effect a substantially water-tght seal between the end of the conduit and a conductor rod passing through the conduit into the ground, and a lid or cover to close the upper part of the housing, said lid or cover being provided with lockable means to lock the cover in the closed position.

Preferably a lid or cover is provided with means to guide pivoting movement of the lid or cover about one edge thereof.

Conveniently said guiding means comprise an apertured depending element extending parallel with one side wall, and an arcuate locating pin engagable with the aperture therein formed on the underside of the lid or cover.

Advantageously lid or cover is provided with one or more locks, each lock comprising a depending structure carrying a substantially radially extending arm, means to move the arm vertically, and means to move the arm rotationally about a vertical axis, the housing having an abutment engageable by the arm.

Preferably the arm is carried on a threaded spindle, means being provided to rotate the threaded spindle, said threaded spindle passing through a first cylindrical housing having an axially extending slit formed in the side wall thereof, said arm extending through the slit, means being provided to rotate the first housing.

Conveniently the first housing is contained within a second cylindrical housing which is secured to the lid or cover, the second housing also hating an 2X- ially extending slit through which said arv projects.

Avvantageous:i the threaded member Is prsv ec with means adapted to co-operate with a specifically configured key to effect rotation of the threaded spindle.

Preferably said means to effect a seal between the upper end of the conduit and the earth conductor comprise a collar adapted to be mounted, by means of screw-threading, on the end of the conduit with a sealing ring trapped between the collar and the conduit, a bore passing through the collar or an element carried thereon, through which the conductor passes, said bore terminating at its lower end with an inwardly directed shoulder, a sealing ring or grommet of a deformable material surrounding the conductor and resting on said shoulder, a split washer located thereabove, and a threaded member engagable with a threaded part of said collar exerting a pressure on the split washer compressing the deformable washer or grommet to firmly engage e-'+A inwardly directed shoulder and the exterior cf the cJn;dctor.

Conveniently said deformable washer or grommet comprises a grommet formed of nylon material.

The unit may have an outlet port.

In order that the invention may be more readily understood, and so that further features thereof may be appreciated the invention will now be described, by way of example, with reference to the accompanying drawings in which FIGURE 1 is a top plan view of an earth seal unit in accordance with the invention, FIGURE 2 is a cross-sectional view of te earth seal unit shown in Figure 1 and FIGURE 3 is an enlarged view of a lock utilised in the earth seal unit.

An earth seal unit in accordance with the invention is intended to be flush mounted so that a lid or cover 1 for the earth seal unit has its upper surface flush with the floor. The lid or cover 1 is in the form of an open topped tray 2. Mounted within the tray 2, parallel with the base thereof, is a welded mesh 3. The tray may be filled with concrete or other similar material 4, as shown in Figure 2. The tray 1 is provided with two locks 5,6 which will be described in greater detail hereinafter. The tray 1 is also provided, at a substantially central location, with an apertured plate 7, which can be utilised to lift the lid or cover 1. The apertured plate 7 is provided with an aperture of non-circular section to enable a key to be inserted through the aperture in the plate and rotated so that part of the key then engages part of the plate.

The lid or cover 1 is mounted on an underlying box 8 fabricated of steel or the like.

The box 8 has a base 9 and upstanding side walls 10. One side wall is provided with, adjacent its upper edge, an "L"-shaped bracket 11, one arm of the "L" being welded or otherwise secured to the interior of the wall 10, so that the bracket provides a horizontally extending arm 12 upon which the lid 1 may rest, and against which the lid may be locked in position. The opposed side wall 10 also carries a "L"-shaped bracket 13 which is welded or otherwise secured in position, this bracket being secured so that one arm 14 extends horizontally away from the side wall 10, and another arm 15 depends at a position spaced from the wall 10.

The depending arm 15 is provided with at least two spaced apart apertures 16 which each receive an arcuate locating pin 17 provided on the underside of the tray 2.

Alternatively two or more bracket sections may be provided, each with a respective aperture 16.

As can be seen from Figures 1 and 2 te apertured plate 7 is located, relative to the locating pins 17, at a position beyond the centre of gravity of the lid or cover 1. Thus, when a key is inserted Into the aperture plate 7 and an upward force is applied, the lid or cover will pivot about the left-hand side thereof. The arcuate locating pins will thus become disengaged from the apertures 16, enabling the lid to be raised.

The lid can be locked in a closed position b means of the locks 5,6. Each lock 5,6, as can be seen from. Figure 3, consists of a cylindrical outer housing 13 which is secured and connected to the underside of the tray 2, this housing having a vertically extending cut-out Li provided in the side wall thereof. A second cylindrical housing 15 is rotatably mounted within the housing 13, this second housing 15 also having an axially extending cut-out 16. The second housing terminates, at its upper end, ith a knob 17 which can be manually rotated to effect rotation of the housing 15. A vertically extending threaded spindle passes down through the centre of the second housing 15 and is operable by means of an appropriate drive 18 which is revealed in a recess 19 formed in the centre of the knob 17. The drive is such that the threaded spindle can only be rotated by an operative having an appropriately configured key which can engage with the end of the threaded spindle. Threadedly mounted on the threaded spindle is a radially projecting arm 20 which projects through the cut-out 16 and through the cutout 14. The width of the arm 20 is substantially equal to the width of the cut-out 15. It will be appreciated that on rotating the threaded spindle the arm 20 will be driven upwardly and downwardly relative to the inner housing 15.Also it will be appreciated that by rotating the knob 17 the arm 20 can be moved angularly.

As can be seen from Figure 2, the arm 20 may be moved to a position where it engages the underside of the horizontally extending part 12 of the bracket 11.

If the drive 18 is then driven appropriately, effecting an upward movement of the arm 20 relative to the housing 15, the lid can be tightly secured in position.

When the lid is, however, to be released, the drive 18 may be driven in the opposite sense, thus disengaging the arm 20 from the horizontally extending portion 12 of the bracket 11 and the knob 17 may be rotated, thus enabling the lid to be lifted.

As can be seen from Figure 2 snap-in covers 21,22 may be provided to cover both the apertured plate 7 and the locks 5 and 6.

The described box has an aperture formed centrally in the base thereof, and the top part 23 of an elongate tube 24 passes through the aperture and is thus within the box 8. The tube is welded into position with a welding 25. The tube carries, at a position below the base 9 of the box 8 a radially extending annular puddle flange 26. The exterior of the upper part of the tube 23 is threaded 27 and a collar 28 is screw-threadally mounted thereon, the collar having an inturned upper lip 29. A leather washer 30 is trapped between the inwardly directed upper lip 29 and the top of the tube 24.

The collar 28 carries a central brass bush 31 which defines a central bore presenting a lower upwardly directed shoulder 32. Resting on the shoulder 32 is â nylon grommet 33 which has, on top of it, a split washer 34. The split washer comprises two semi-circular washer portions which are located in position to make a complete washer. A tubular member 35 having an external threading is then threadedly engaged in the threaded upper part of the bore extending through the member 31 to engage the split washer. The split washer is thus compressed against the nylon grommet 33 which in turn forms a water-tight seal against an elongate conductor member 36 which passes downwardly through the tube 24 into the ground.

It is to be noted that the conductor member 36 te-m -ates with a spun thread 37 which is of greater diameter than the diameter of the body of the tube 36.

When an earth seal unit in accordance with the invention is utilised, the box of the earth seal unit is appropriately positioned, and may be embedded in concrete or the like. With the lid 1 and the collar 28 In the associated components not in position, the conductor 36 is hammered down, through the pipe 2X, into position. The earth conductor 36 must establish an adequate contact with the underlying geological formation, and it may be necessary, when a first length of conductor has been hammered into position, to connect a further length of conductor to the first length, by means of a threaded connector sleeve which serves to interconnect the threaded ends of two lengths of conductor 36. (This is illustrated in phantom in Figure 2).However, when a sufficient length of conductor (or conductors) 36 has been driven down into the ground, such that adequate electrical contact is established with the ground, then the collar 28, and the associated leather washer 33, are located in position. The upper end of the conductor 36 passes through the central aperture formed in the boss 31. Subsequent y the nylon grommet 33, which does have some slight degree of resilience, can be eased over the enlarged threaded end 37 of the conductor 36 and can then be slid down the conductor to rest on the inwardly directed shoulders 32 defined by the boss 31. Subsequently the elements forming the split washer 34 may be located L position.It is to be noted that it is preferred for the diameter of the central aperture formed by the split washer, when assembled, to be substantially equal to the diameter of the unthreaded portion of the conductor 36. Subsequently the tubular member 35 is passed over the enlarged threaded end 37 of the conductor 36, and is threadedly engaged with the threaded upper part of the bore defined through the boss 31, ant is then tightened into position thus forcing the split washer 34 against the nylon grommet 33. The nylon grommet 33 is deformed, and then provide≈a water-tight seal between the inwardly directed shoulder 32 and the exterior surface of the conductor 36. It is to be noted that the member 35 has a central bore therethrough whic is of such a d.- ameter that it can be passed over the threading 37 provided at the end of the conductor 36. Thus the upper end of the tube 24 is effectively sealed, and it has been found that the seal provided by the described technique can withstand a pressure of three bars.

If desired an outlet port 38 may be provided in one side wall of the box. This is a conventional outlet port leading to a length of conduit 39 made of a plastics material. Further lengths of conduit may be secured to this port by means of solvent adhesive or the like.

Claims

CLAIMS:

1. An earth seal unit, said unit comprising a housing defining a base and side walls, a conduit extending up into the housing through the base, means to effect a substantially water-tight seal between the end of the conduit and a conductor rod passing through the conduit into the ground, and a lid or cover to close the upper part of the housing, said lid or cover being provided with lockable means to lock the cover in the closed position.

2. An earth seal unit according to Claim 1 wherein a lid or cover is provided with means to guide pivoting movement of the lid or cover about one edge thereof.

3. An earth seal unit according to Claim 2 wherein said guiding means comprise an apertured depending element extending parallel with one side wall, and an arcuate locating pin engagable with the aperture therein formed on the underside of the lid or cover.

4. An earth seal unit according to any one of the preceding Claims wherein the lid or cover is provided with one or more locks, each lock comprising a depending structure carrying a substantially radially extending arm, means to move the arm vertically, and means to move the arm rotationally about a vertical axis, the housing having an abutment engageable by the arm.

5. An earth seal unit according to Claim 4 wherein the arm is carried on a threaded spindle, means being provided to rotate the threaded spindle, said threaded spindle passing through a first cylindrical housing having an axially extending slit forme in the side wall thereof, said arm extending through the slit, means being provided to rotate the first housing.

6. An earth seal unit according to Claim 5 wherein the first housing is contained within a second cylindrical housing which is secured to the lid or cover, the second housing also having an axially extending slit through which said arm projects.

7. An earth seal unit according to Claim 5 or 6 wherein the threaded member is provided with means adapted to co-operate with a specifically configured key to effect rotation of the threaded spindle.

8. An earth seal unit according to any one of the preceding Claims wherein said means to effect a seal between the upper'end of the conduit and the earth conductor comprise a collar adapted to be mounted, by means of screw-threading, cn the end cf the conduit with a sealing ring trapped between the collar and the conduit, a bore passing through the collar or an element carried thereon, through which the conductor passes, said bore terminating at its lower end with an inwardly directed shoulder, a sealing ring or grommet of a deformable material surrounding the conductor and resting on said shoulder, a split washer located thereabove, and a threaded member engagable with a threaded part of said collar exerting a pressure on the split washer compressing the deformable washer or grommet to firmly engage said inwardly directed shoulder and the exterior of the conductor.

9. An earth seal unit according to Claim 8 wherein said deformable washer or grommet comprises a grommet formed of nylon material.

10. An earth seal unit according to any one of the preceding Claims provided with an outlet port.

11. An earth seal unit substantially as herein described with reference to and as shown in the accompanying drawings.

12. Any novel feature or combination of features disclosed herein.