GB2361500A

GB2361500A - A Frame For A Manhole Cover Or Gully Grating

Info

Publication number: GB2361500A
Application number: GB0108893A
Authority: GB
Inventors: Peter Derrick Savage
Original assignee: Peter Savage Ltd
Current assignee: Peter Savage Ltd
Priority date: 2001-04-09
Filing date: 2001-04-09
Publication date: 2001-10-24
Anticipated expiration: 2021-04-09
Also published as: GB0108893D0; GB2361500B

Abstract

A frame for a manhole cover or a gully grating has an external flange 2, the underside of which has pockets 6,8 to improve the security of the frame's mounting in the ground. The pockets 6,8 may be sub-divided bay ribs 9. Further projections 13,14 may extend from the flange 2 in an upward or downward direction.

Description

2361500 A Frame for a Manhole Cover or Gully Grating This invention

relates to frames to suit manhole covers and/or gully gratings, offering an improved method of fixing and maintaining the position of the frames onto suitable bedding material.

A typical existing frame for a manhole cover and grating will have flanges that are flat on the underside, thus offering no proper keying between the bedding mixture and the underside of the frame. Some frames for heavy duty road type manhole covers may only have flanges at the four comers of the unit for seating and for building in/and fixing purposes. With larger frames to accept multiple covers there may only be frame flanges corresponding with the seating points of the covers fitted therein. These flanges will be flat on the underside. Anchorage holes in the frame for bolting down purposes may also be included.

It is an object of the present invention to provide a manhole cover or grating frame which includes features to enhance the safety, stability and security of the frame in place.

According to one aspect of the present invention there is provided a frame for a manhole cover or gully grating in which parts of the frame are formed to provide secure fixing with a suitable bedding mixture.

By means of this invention, the frames of covers or gratings are constructed in a manner that offers maximum opportunity for the frame to satisfactorily key on to suitable bedding/fixing material to prevent movement in any direction during trafficking.

In order to more securely prevent movement of frames of manhole covers and gratings of any load bearing type on to a suitably prepared area of bedding material, a series of pockets are recessed preferably into the underside of frame flanges at time of 3 manufacture. (Anti Movement Pockets (trade mark)).

2 The invention has benefits for frames of any size and loading. The pockets will be particularly useful with products of the BS-EN 124 D400 (40 tonne loading) and BS-EN124 E600 (60 tonne loading), especially in highly trafficked areas where frames of covers and gratings are more susceptible to movement if not sufficiently bedded and keyed to fixing material. The pockets are also particularly useful for frames of large size.

The pockets, being recessed into the underside of the frame, will trap bedding mixture which, when settled and hardened, will hold the frame in place. The pockets will surround quantities of the bedding mixture, improving the ability of the frame to resist movement in any direction.

These anti movement pockets are formed by rebating into the underside of the thickness of the flange of the frame at time at time of manufacture. This is the most convenient location for the pockets in manufacturing and is the best location for preventing horizontal movement of the frame as it gives a direct key to the bed defining the chamber beneath the frame for secure fixing.

The pockets can be of any suitable shape or size to best suit the width of the frame flange.

The pockets may be separated into smaller pockets by ribs which may be part of or integral with the frame. This enhances the hold of the pockets on the bedding mixture.

The pockets may be open at the outside edge of the frame flanges. This allows bedding mixture to enter and fill the pockets and helps prevent movement of the frame in any direction.

The pockets may be recessed into the underside of the straight lengths of the frame flanges. The straight lengths of the frame flanges may be large in area in comparison with the comer sections, so larger pockets can be formed there. This location of pockets helps prevent horizontal movement of the frame.

3 The pockets may be recessed into the comers of the underside of the frame flanges and may be at an angle to the comer. This location of the pockets helps prevent unwanted movement of the frame.

There may be pockets in the comers of the frames flanges and in the straight lengths of the flanges of the frame. This combines the advantages of pockets in those locations to give maximum hold of frame onto suitable bedding mixture.

Upstandings or downstandings may be formed on the edge of the frame flanges. When the bedding mixture has settled around the upstandings they will hold the frame firmly in place. The upstandings may be continuous around the edge of the frame flanges.

This maximises the stability that the upstanding affords. Alternatively, the upstandings may be formed in lengths on the edge of frame flanges. This saves on the amount of material required for the upstandings. The lengths of upstandings are placed in optimum locations for stability.

In another embodiment of the present invention, part of the outside edge of the frame flange may be arranged at an angle to the main part of the frame flange. This has the effect of creating a shallow open pocket with the advantages discussed above.

Ribs may protrude from the frame flanges and may protrude underneath the angled edge of the flange. The ribs provide additional fixings in the bedding mixture.

The pockets may be aligned with the edges of the frame or may be at an angle thereto.

In one embodiment two adjacent pockets are at different acute angles to the adjacent edge of the flange.

Embodiments of the present invention will now be described by way of example only and with reference to the accompanying drawings, in which:

Figure 1 is a top plan view of a manhole cover frame according to the first embodiment of the invention; 4 Figure 2 is an underneath plan view of the frame of Figure 1; Figure 3) is a side elevation of the frame of Figure 1; Figure 4 is a detail side elevation in cross section at A-A in Figure I - Fiaure 5 is a detail side elevation in cross section at X-X in Figure 2; Figure 6 is a detail view of part of Figure 5; Figure 7 is a detail underneath plan view of a frame of a second embodiment; Figure 8 is a side elevation of a frame in a third embodiment; Figure 9 is a detail side elevation in cross section of one side of the frame of Figure 8; Figure 10 is a side elevation of a frame in a fourth embodiment; Figure I I is a detail side elevation in cross section of one side of the frame of Figure 10, Figure 12 is a side elevation of a frame in a fifth embodiment; Figure I') 'is a detail side elevation in cross section of one side of the frame of Figure 12; Figure 14 is a side elevation of a frame in a sixth embodiment; and Figure 15 is a detail side elevation in cross section of one side of the frame of Figure 14.

The principal components of the frame of the first embodiment are a short tubular section I of substantially square cross section and a flange section 2 which extends outwards from the lower edge of the tubular section and perpendicular to it.

The tubular section 1 has rounded comers. Seatings 3 are formed diagonally across the inside of each comer. When emplaced, the manhole cover sits on these seatings 3.

Each seating 3) is supported by an upright web 4.

The flange 2 is continuous around the lower edge of the tubular section I and its width is approximately constant. The width of the flange 2 is approximately two thirds of the height of the tubular section I which is the traditional arrangement.

0 The flange 2 is held relative to the tubular section I by buttressing flanges 5, one near each comer.

Pockets 6, 8 are formed by shallow recesses into the underside of the flange 2. At each comer of the flange 2, square comer pockets 6 are formed at 45' to the comer. Each comer pocket 6 contains a keying rib 7 formed along the centre of the comer pocket 6 oriented in a direction perpendicular to the radial direction of the comer. The keying 5 ribs 7 do not protrude beyond the main underside surface of the flange 2.

Side pockets 8 are formed on the underside of each of the straight lengths of the flange 2. Dividing ribs 9 separate the side pockets 8 into mini pockets. The side pockets 8 are rectangular and the dividing ribs 9 are oriented in a direction perpendicular to the edge of the flange 2 and are equi-spaced to result in four equal sized rectangular mini pockets.

A number of lengths of upstandings 10 are formed on the upper side of the flange 2, one at each comer and two along each straight length. The upstandings 10 are formed along the outer edge of the flange 2 and are perpendicular to it. An upstanding buttress I I is formed behind each upstanding 10, connecting it to the flange 2 to support the upstanding 10.

The advantages of the present invention as described in any of the embodiments refer to the fixing of the manhole cover frame in suitable bedding mixture. The side pockets 8 and comer pockets 6 trap bedding mixture within them to firmly hold the frame in place. The upstandings become surrounded by bedding mixture when the frame is emplaced, preventing the frame from moving relative to the bedding mixture.

The webs 4 are optional depending upon the size and anticipated loading of the frame and its depth. The angle of the comer pockets 6 can be altered as desired to suit the circumstances, and the pockets may be at 90', i.e. square on, at the comers, although the 45' angle is preferred. The keying rib 7 in each comer pocket 6 may be omitted or there may be more than one rib 7 in each comer pocket in alternative embodiments. In a ftirther alternative embodiment the comer pockets 6 are omitted entirely.

6 The comers of the flange can be rounded, as shown, or square, cut off at an angle or can be in any other desired shape.

The dividing ribs 9 are also optional or may be present in greater or lesser number 5 depending upon the size of the frame.

Although rectangular pockets 6, 8 have been shown, the pockets can be in any desired shape, whether regular or irregular, straight sided or otherwise, and in any desired number, in particular depending on the size of the frame.

The second embodiment of the invention is similar to the first and only the differences from the first embodiment will be described. In the second embodiment as shown in Figure 7, the side pocket 8 on each straight part of the flange 2 is replaced by two rectangular pockets 20. The pockets 20 are at opposite acute angles to the edge of the flange 2 in a symmetrical arrangement. This angling of the pockets 20 assists in holding the frame against movement in any direction, as the edges of the pockets 20 are at different angles to one another and to the edge of the flange 2 and tubular section 1.

The pockets 20 can be at any desired angle. Although a symmetrical arrangement is shown and preferred, asymmetrical arrangements are also envisaged.

In a third embodiment of the present invention as shown in Figures 8 and 9, the side pockets 12 are open at the edge of the flange 2. There are no upstandings; on the flange 2. The second embodiment is the same as the first embodiment in every other detail.

In a fourth embodiment of the present invention as shown in Figures 10 and 11, a single upstanding 13 is continuous all the way around the upper outside edge of the flange 2. The upstanding 13 is supported at intervals by triangular buttresses 16. There may or may not be side pockets. The third embodiment is the same as the first embodiment in every other detail. The upstanding 13 aids prevention of movement of the cover.

7 The frame in a fifth embodiment of the present invention as shown in Figures 12 and 13 is the same as the fourth embodiment except that there is also a continuous upstanding 14 below the outer edge of the flange 2. The upstanding 14 is supported at intervals by triangular buttresses 18.

In the sixth embodiment of the invention as shown in Figures 14 and 15 the upstanding 13, 14 is replaced by an edge portion 22 of the flange 2 which is angled upwardly at a shallow acute angle of, say, 30' and extends over the central part of the straight length of each side of the flange 2. Two supporting ribs 24 are provided beneath the angled edge portion to form three pockets. As before, the number of ribs 24 provided can be altered as desired, for example, depending upon the size of the cover.

In the embodiments of the present invention described the manhole cover frame may be formed from a single piece of iron.

Claims

8 Claims

1. A frame for a manhole cover or gully grating in which parts of the frame are formed to provide secure fixings with suitable bedding mixture.

A frame as claimed in claim 1 in which the parts of the frame formed to provide secure fixing define pockets recessed into parts of the frame.

3. A frame as claimed in claim 2, wherein the pockets are downwardly facing. 10 4. A frame as claimed in claim 2 or claim 3, wherein each pocket defines a straight sided figure in plan.

5. A frame as claimed in claims 2, 3 or 4, wherein the pockets are in a symmetrical arrangement.

6. A frame as claimed in any of claims 2 to 5, wherein the pockets are separated into smaller pockets by ribs.

7. A frame as claimed in claim 6, wherein the ribs are integral with the frame.

8. A frame as claimed in any of claims 2 to 7, wherein the pockets are recessed into flanges on the frame.

9. A frame as claimed in claim 8, wherein at least one of the pockets is open at the edge of the frame flange.

10. A frame as claimed in claim 8 or claim 9, wherein the frame flange is in the plane of the manhole cover. no 11. A frame as claimed in claim 8, 9 or 10, wherein the frame is in a shape having corners and a pocket is recessed into at.least one comer of the frame flange.

9 12. A frame as claimed in claim 11, wherein at least one pocket is recessed into each comer of the frame flange.

11 A frame as claimed in claim I I or claim 12, wherein the or each comer pocket is at an angle to the comer of the frame flange.

14. A frame as claimed in any of claims 8 to 13, wherein the frame flange has straight lengths and at least one pocket is recessed into a straight length of the frame 10 flange.

15. A frame as claimed in claim 14, wherein at least one pocket is recessed into each straight length of the frame flange.

16. A frame as claimed in claim 14 or claim 15, wherein the or at least one pocket is at an angle to the axis of the straight length in which it is recessed.

17. A frame as claimed in claim 16, wherein two adjacent pockets in a straight length are at different acute angles to the axis of the straight length.

18. A frame as claimed in any preceding claim, wherein at least one upstanding or downstanding is formed on the edge of the frame.

19. A frame as claimed in claim 18, wherein there is one upstanding and/or 25 downstanding which is continuous around the edge of the frame.

20. A frame as claimed in claim 18 or claim 19, wherein a plurality of upstandings and/or downstandings are formed in discrete lengths on the edge of the frame.

21. A frame as claimed in any of preceding claims 2 to 20, wherein the frame includes a flange and at least one part of the outside edge of the frame flange is raised at an angle to form a pocket.

22. A frame substantially as described herein with reference to Figures I to 6, 7, 8 and 9, 10 and 11, 12 and 13 or 14 and 15 of the accompanying drawings.