GB2073289A

GB2073289A - Improvements in or relating to grids manholes and the like

Info

Publication number: GB2073289A
Application number: GB8009659A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-03-21
Filing date: 1980-03-21
Publication date: 1981-10-14

Abstract

A cover unit for a hole in a road, pavement or the like, for example a grid or manhole cover, has three nesting parts 11, 12, 13 with conforming surfaces so that, during re-surfacing of the road the intermediate part 12 can be removed to prevent the unit being proud of the surface after an upper layer of road surface has been removed. The intermediate part is replaced when the upper layer is replaced. <IMAGE>

Description

SPECIFICATION Improvements in or relating to grids manholes and the like This invention relates to cover units for a hole in the ground, road or the like, for example grids, manholes.

According to this invention there is provided a cover unit for a hole in the ground, road or like comprising an upper part, an intermediate part defining an aperture, and a lower part defining an aperture, the upper part being adapted to nest in the intermediate part which is adapted to nest in the lower part, the upper part being adapted to nest in the lower part.

The invention also includes a method of resurfacing a road or the like in which such a cover unit is located with the parts nested comprising removing the intermediate part.

The intermediate part will usually be removed, and the upper part nested in the lower part, prior to removal of an upper layer of the road, the intermediate part being replaced prior to the laying or a replacement upper layer.

The invention may be performed in various ways and one specific embodiment with possible modifications will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is a section on the line 2-2 of Fig.

4 with the parts assembled of a grid unit; Figure 2 is a section on the line 2-2 of Fig.

4; Figure 3 is similar to Fig. 1 but with one part removed; and Figure 4 is a perspective exploded view of the unit.

The grid unit 10 comprises a top grid part 11, a hollow intermediate part 12, and a hollow bottom part 1 3. The grid parts are generally rectangular. Part 11 has transverse parallel bars 14 and downwardly facing lower surface conforming to part of the upwardly facing surface on the intermediate part 1 2 whose lower surface conforms to the upper surface of the bottom part 1 3. The lower face of part conforms to part of the upper face of bottom part 1 3.

The width and length of the top part 11 are less than the corresponding dimensions of part 1 2 so that when the parts nested as in Fig. 1 the lateral peripheral side surface 1 5 of the top part 11 is close to the inwardly facing peripheral surface 1 6 of the intermediate part 12.

The lower surface of top part 11 comprises horizontal peripheral surface 1 7 and inwardly and downwardly inclined peripheral side surface 1 8. When nested these conform respectively to horizontal surface 1 9 and downwardly and inwardly inclined surface 20 of the upper surface of part 12.

The bottom part 1 3 has the same width and length as part 1 2 and its upper surface 1 6a, 1 9a, 20a corresponds to the surfaces 16, 19, 20. Thus part 11 can be nested in part 13, as seen in Fig. 3, in å similar manner to the nesting of part 11 in part 1 2. The lower face of part 1 2 has surfaces 1 7a, 1 8a corresponding to surfaces 17, 1 8 and can thus nest in part 14, as seen in Fig. 1, with horizontal peripheral surface 21 engaging horizontal peripheral surface 22 of part 1 3.

Normally with the grid unit installed in a road or gutter the road or gutter level is at 30, substantially flush with the upper surface 23 of part 11 and upper surface 24 of part 1 2. When the road or gutter requires resurfacing, it is usual to burn off or otherwise remove an upper layer 31 of said up to 7.5 cms bringing the ground level to 32. Parts 11, 1 2 can then be lifted, part 1 2 removed, and part 11 replaced to be nested in part 1 3 with the upper surface 23 of part 11 and the upper surface 22 of part 1 3 both substantially flush with the new ground level 32.

The height of lateral side surface 25 of part 12 is, for example, 7.5 cms.

When the road has been re-surfaced, bringing the road level back to 30 or immediately prior to re-surfacing, part 1 2 can be replaced returning the unit to the condition of Fig. 1. The part 1 3 will usually be fixed relative to the road, for example secured in brickwork 28.

This construction of unit which is substantially flush with the ground layer has been burnt off is to be contrasted with a conventional grid which has two parts, the upper part being removable, in which the lower part is fixed in the road and is thus proud of the road after the upper layer of the road is burnt off.

When the bottom part is thus proud of the road level, this presents an obstruction to road users which can be dangerous and results in undue wear on vehicles engaging the obstructions.

In the arrangement shown the parts 11, 12, 1 3 define apertures. In a modified construction the invention is applied to a manhole cover unit of circular plan view and in which the top part is solid, parts 12, 1 3 again defining apertures and providing access to the manhole. The invention can also be applied to similar cover units for holes in the ground, such as holes providing access to water taps, electric cables, gas pipes and telephonic equipment.

It will be appreciated that the parts 11, 12, 1 3 which for example are of cast iron are a close but not tight fit within each other.

There could be a further intermediate part, similar to part 11, between parts 11 and 12, or 1 2 and 13, having upper and lower surfaces generally similar to those of part 11.

In a modification shown in Fig. 1, the intermediate part 1 2 has an inner peripheral portion 35 extending inwardly from the inner surfaces of the upper and lower parts and providing a downwardly facing horizontal lifting surface 36. The upper surface of portion 35 is also horizontal.

Claims

1. A cover unit for a hole in the ground, road or the like comprising an upper part, an intermediate part defining an aperture, and a lower part defining an aperture, the upper part being adapted to nest in the intermediate part which is adapted to nest in the lower part, the upper part being adapted to nest in the lower part.

2. A cover unit as claimed in Claim 1 in which the lower surface of the upper part conforms with part of the upper surfaces of the intermediate part and the lower part.

3. A cover unit as claimed in Claim 1 or Claim 2, in which the lower surface of the intermediate part conforms with the upper surface of the lower part.

4. A cover unit as claimed in Claim 2 Or Claim 3, in which the lower surface of the upper part has a horizontal outer part and an inwardly inclined downwardly extending inner part.

5. A cover unit as claimed in Claim 2 or Claim 3 or Claim 4, in which the upper surfaces of the intermediate and lower parts have an outer horizontal surface.

6. A cover unit as claimed in any preceding claim, in which the upper part is substantially flush with the intermediate part when nested therein, and is substantially flush with the lower part when nested therein.

7. A cover unit as claimed in any preceding claim, in which the intermediate part has a downwardly facing inner lifting surface.

8. A cover unit substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

9. A method of re-surfacing a road or the like in which a cover unit as claimed in any preceding claim is located with the parts nested comprising removing the intermediate part.