AU2019101123B4 - System and method of temporary protection of a pit - Google Patents

Abstract

Abstract A covering of an in-ground structure, comprising a flexible wall and a lid member, overlapping at the peripheral portion in closed position.

Description

SPECIFICATION FOR A PROVISIONAL PATENT APPLICATION

SYSTEM AND METHOD OF TEMPORARY PROTECTION OF A PIT

Field of invention [01] This invention relates to the covering of an in-ground structure such as a pit under construction, to help prevent debris and detritus entering it, and to prevent personnel and others on a building site accidentally falling in during the construction and pre-commissioning stages.

Background to the invention [02] A significant operating cost borne by civil construction operators arises from having to clear foreign material that has entered in-ground pits that have been pre-installed in roads, subdivisions, waterways, easements and the like while under construction and before commissioning. The material may be debris resulting from ongoing ground levelling and road building operations as well as water, dirt and litter from adverse weather conditions. Pits currently are often left inadequately covered or even completely uncovered until ground levelling and road building operations are completed, creating a safety hazard and causing an increase in costs.

[03] When a partially constructed pit is left unattended and inadequately covered or uncovered while other work is progressed, unauthorised entrants to a building site as well as onsite personnel are at risk of injuring themselves by tripping on a surrounding wall and falling in or striking another part of the wall.

[04] International Patent Publication WO1996015325 (Woodman).discloses a pit cover with a stiff lid and a surrounding skirt. The skirt is typically made of rubber, but may be of any other suitable resilient material. The skirt fits inside the surrounding walls to sit flush against them. Moreover, the skirt does not surround the entire pit. It is intended only to provide a barrier at the rebated portion of the pit. The rubber skirt extends only a short way back from the rebated front wall. The

2019101123 27 Sep 2019 skirt is perforated, so as to allow ingress of water, but to hold back solid debris. There is no suggestion that the skirt should be applied to the outside of a pit or to surround the pit and the rebated front wall.

[05] Chinese patent publication CN2407038Y discloses a temporary cover for a pit that has a metal skirt integrated with a lid.

[6] It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative, and in doing so, to provide a temporary protective system for an in-ground structure such as a pit that minimises risk of fall injury.

[7] The preceding discussion of the background to the invention is intended to facilitate an understanding of the present invention. However, it should be appreciated that the discussion is neither acknowledgement nor admission that any of the material referred to was part of the common general knowledge in Australia or elsewhere at the priority date of this application.

[8] Further, and unless the context clearly requires otherwise, throughout the description and the claims, the words ‘comprise’, ‘comprising’, and the like are to be construed in an inclusive sense, meaning “including, but not being limited to”, as opposed to an exclusive or exhaustive sense, meaning “including this and nothing else”.

Summary of invention [09] According to a first aspect of the invention there is provided a temporary in-ground pit cover comprising a flexible wall membrane vertically disposable in use to surround an in-ground pit from an upper open end thereof to at least a level of surrounding ground and, attached to at least a portion of the wall, a lid membrane disposable horizontally to cover the pit and adapted for operative association with reinforcing means for preventing a human falling into the pit, wherein the lid membrane comprises a peripheral portion overlapping the wall membrane when the lid is in closed position.

2019101123 27 Sep 2019 [10] An advantage of the invention is that it also prevents foreign matter from entering an incomplete structure, such as the pit when covered.

[11] The invention also provides a means of visually highlighting an incomplete structure (the pit) to machine operators and personnel in general, especially in embodiments where the cover may be made of a bright material.

[12] Preferably, the wall and lid membranes are integrally formed to be attached.

[13] In an alternative embodiment, said wall and lid membranes are separately formed and thereafter are operatively attached by attachment means.

[14] In a preferred form of the invention, the cover comprises fastening means operably located for fastening a peripheral portion of the lid membrane to an adjacent peripheral upper end portion of the wall membrane so that the wall membrane defines a flexible cylinder having an upper end closed by the lid membrane when fastened.

[15] The fastening means may comprise mechanical means, including hinge means, a hook-and-loop fastener, stitching, or a zipper. It may also include bonding means such as thermal bonding and adhesive bonding.

[16] In a preferred embodiment, the lid membrane comprises a peripheral portion overlapping the wall membrane when the lid is in closed position.

[17] In a further preferred form of the invention, the reinforcing means comprises a rigid structure of generally flat proportions. Preferably, the rigid structure is capable of supporting an adult human’s weight.

[18] Preferably, the rigid structure comprises a plate or sheet, a set of parallel bars, or a grille, grid or mesh.

[19] In a still further preferred form of the invention, the lid membrane is adapted for association with the reinforcing means by comprising engagement means capable of operative engagement with the reinforcing structure.

2019101123 27 Sep 2019 [020] The lid membrane may be adapted for association with the reinforcing means by comprising a structural feature for receiving the reinforcing structure.

[021] In an embodiment, the structural feature comprises a sleeve.

[022] Preferably, the sleeve is accessible from an inside surface of the cover.

[023] In a yet further preferred form of the invention, the wall membrane comprises a peripheral lower strip adapted for spreading on ground surrounding a pit structure being covered.

[024] According to a second aspect of the invention, there is provided a method of temporarily barring ingress of foreign matter to an uncommissioned inground structure defining a cavity, the method comprising the steps of providing a protection system having one or more of the features set out above, placing the protection system in operative orientation in relation to the uncommissioned structure and ensuring that entry to the cavity is barred.

[025] In a preferred form of the invention, the structure is a pit and the protection system comprises a cover having an openable and closeable lid. The method preferably includes bringing the lid to closed position.

[026] Preferably, the method further includes fastening a peripheral portion of the lid membrane to an adjacent peripheral upper end portion of the wall membrane.

[027] In a preferred form of the invention, the method includes the step of allowing the wall membrane of the cover to reach to the level of ground surrounding the pit structure.

[028] In a preferred form of the invention, the method includes spreading a lower peripheral portion of the wall membrane on the surrounding ground.

[029] According to a third aspect of the invention there is provided a kit for providing temporary protection to an uncommissioned in-ground structure defining a cavity, the kit comprising a cover having a flexible wall membrane vertically

2019101123 27 Sep 2019 disposable in use to surround an in-ground uncommissioned structure from an upper open end thereof to at least a level of surrounding ground and a lid membrane disposable to cover the structure and cavity and adapted for operative association with reinforcing means for preventing a human falling into the cavity, the lid membrane being connected or connectable to at least a portion of the wall.

[030] In a preferred form of the invention, the kit includes said reinforcing means.

Brief description of drawings [031] In order that the invention may be readily understood, and put into practical effect, reference will now be made to the accompanying figures. Thus:

Figure 1 illustrates in perspective view an in-ground pit of known design, to which the cover of the invention may suitably be applied..

Figure 2 is a schematic plan view of the temporary cover of the invention in a preferred embodiment, showing its outer surface when laid out in an inoperative manner.

Figure 3 is a schematic view of the cover of Figure 2 being placed over a pit of the type illustrated in Figure 1 with the lid open.

Figure 4 is a schematic view of the cover of Figure 2 in operative covering position over a pit of the type illustrated in Figure 1.

Figure 5 schematically illustrates a cover of Figure 2 in place over a pit of the kind shown in Figure 1, but with the cover lid in partially open position.

Figure 6 schematically illustrates a cover of an alternative embodiment to Figure 2 placed over a pit of alternative shape to the pit in Figure 1, the lid of the cover being in partly open position.

2019101123 27 Sep 2019

Detailed description of an embodiment of the invention [032] An embodiment of the invention will now be described, using as example a cover designed for an in-ground pit which has not been commissioned and is located in a construction site and is surrounded by ongoing construction work.

[033] Referring to Figure 1, an in-ground pit structure of known design is shown in isolation as a non-limiting example of a pit structure with which a preferred embodiment of this invention may be used. A fabric blank for manufacturing the cover of the invention is shown in Figure 2 and the cover of the preferred embodiment is shown being drawn over the pit into operative use in Figure 3. Like numbering is used throughout to designate like features.

[034] In Figure 1, the pit structure 12 comprises a concrete wall 14 of rectangular cylindrical cross section when the pit is viewed in a vertical axial direction. The wall has a generally planar top surface 16. Surrounded by the wall is a hollow cavity defining a pit 18. Front wall 20 in this example is rebated to provide a lower top surface 22 than the level of top surface 16, so that in use stormwater may drain into the pit over surface 22 of the structure in preference to surface 16. Visible in Figure 3 is a drainage outlet 24 that is connected into the stormwater system associated with a road to be constructed adjacent pit structure 12 in use.

[035] In Figure 2, the pit cover blank 10 in this embodiment comprises a single piece of a waterproof fabric 30 cut to predetermined dimensions to define an elongate side wall membrane 32 and a pit covering lid membrane 34. The fabric may be woven, non-woven, knitted or plasticised, and made from either a polymer or natural fibre. Suitable, but by no means limiting, examples of synthetic fabrics are nylon, Goretex®, polypropylene, polyester and polyvinyl chloride. Natural fabrics include cotton, flax, hemp, sisal, loin. Combinations or blends of two or more of these may be used, from either or both fabric groups.

[036] In this embodiment, fold lines 36 (only some of which are numbered) in fabric 30 define panels that are respectively sized for disposition against the outer surfaces of walls 14 and 20 of the pit and over its upper surfaces 16, 22 and the pit

2019101123 27 Sep 2019 opening. The panel dimensions are selected to be greater than the standard dimensions of the pit type for which the cover is intended. The result is that the protective system embodied in the cover will fit comfortably over and around the pit wall in use, as discussed further below in this specification.

[37] Side wall membrane 32 is comprised of side wall panels 42, 44, 46 and 48 and is intended to hang skirt-like from the outer edges of surfaces 16 of the pit wall to surround pit 12 of Figure 1. Panel 46 is placed to be adjacent the outer surface of lower wall portion 20. Lid membrane 34, intended for horizontal operative placement over pit opening 18 in Figure 1, is connected to wall membrane 32 at panel 46 by connecting strips 52, 54, defined by fold lines 36 between them and adjacent panels 34 and 46.

[38] Lid membrane 34 is made up of a double layer of fabric so that it includes a sleeve 40 to which access is gained via a slit 38 adjacent connecting strip 54. A rigid reinforcing plate (not shown) is inserted into the sleeve. The cover subassembly comprising the membrane with the plate received into the sleeve is rendered capable of supporting the weight of a large adult falling on it from standing height. There is also a sleeve in panel 52 that holds a reinforcing plate to stop debris from entering into the pit cavity. In this embodiment, the plate is made of moisture-resistant medium density fibreboard (MDF), selected to be able to resist the weight of a large adult (having a weight of up to about 120kg tripping and falling on to it). However, it will be appreciated that other materials and structures, including grilles and grids may be used as alternatives. Examples of plate materials include (without limitation) sheets of plywood, steel, aluminium, chipboard, plastics and composites.

[39] Fold lines also serve to demarcate and distinguish top covering strips 56, 58 and 60 from their respective vertical sidewall panels 42, 44 and 48. These strips fold over the outer edges of the pit structure walls.

[40] Each panel and strip making up the wall and lid membranes 32, 34 is generously sized to allow a snug but not tight fit around and over pit structure 12. This is for ease of fitting despite variations in dimensions in individual pit

2019101123 27 Sep 2019 constructions due to permitted tolerances and to allow for expansion or contraction as temperatures fluctuate. The result is that the cover may take on a somewhat baggy appearance when fitted to a pit structure manufactured to the low end of a manufacturing tolerance range. The visual appearance of the flexible wall material, especially when presented in a high-visibility colour, helps draw attention to the cover and the pit beneath it, so that the risk of accidental collision with it is reduced. Without wishing to be bound by theory, it is surmised that this advantage arises because bagginess of appearance is not reproducible from one covered pit structure to the next and results in each covered pit structure taking on a unique shape and profile, aided by variation in the lie of the land surrounding each pit.

[041] As a preferred, but optional feature, the wall panels are provided with a trapezoidal skirting strip 62 to lengthen the wall sufficiently to form a skirt that, for standard constructions of pit enclosures, will extend at least to ground level and spread out adjacent the structure. Adjacent strips on adjoining wall membrane panels are trapezoidally shaped for overlapping at ground level. This provision for excess length helps ensure that debris is less likely to be able to be blown up between the skirt and the structure, but is more likely to be blown against and on to the horizontally spread peripheral skirting strips 62.

[042] Zippers are fixed to the free edges of the membrane panels to enable forming of a coherent assembled structure around the pit construction. Thus the vertical end edges of membrane 32 are provided with mating zipper strips 64a, 64b. When this zipper is fastened, the panels of wall membrane 32 form a cylindrical fabric wall that fits around pit structure 12.

[043] A pairing 66a, 66b of hook and loop fasteners is available to fasten the distal periphery of lid membrane 34 to the rear wall panel 42. The fastener elements 66b are located on the opposite side of membrane 34 so are not strictly visible in the view shown in Figure 2. They are therefore shown schematically in stippled lines. With the hook and loop connectors fastened, lid membrane 34 overlaps horizontally extending strips 56, 58 and 60 in use.

2019101123 27 Sep 2019 [044] Membrane 34 has peripheral strip portions 68a, 68b and 70 which serve to extend over the external edges of surfaces 16 of pit construction 12. These extensions hang down over panels 42, 44 and 48 and inhibit entry of rubble and windblown debris below membrane 34.

[045] Connecting panels 52, 54 enable as step form to result for covering a pit structure having a rebate, as exemplified in Figure 1. In cases where a pit to be covered has no such rebate but has sides of equal height, panel 52 is vertically arranged and panel 54 horizontally arranged to extend substantially in the same plane as membrane 34. Although not shown, additional zips or other fastening means, including stitching, may be provided to fasten the sides of panels 52 and 54 to the adjacent recess edges of panels 44 and 48.

[046] Referring to Figure 3, the assembled cover is shown fitted externally to pit structure 12. Lid 34 is shown flipped open to reveal the pit 18 of structure 12. To cover the pit, the lid is flipped back over the pit, as indicated by directional arrow D. Depending on the depth of the pit, suitably qualified personnel may be permitted to continue work inside during the construction period. For ease of handling, fabric gripping loops 72 (not all of which are shown in Figure 2) are optionally provided on the lid and corners of the walls. The loops enable insertion of star pickets and the like through them into surrounding soil, for securing the pit cover in place and to the ground. The loops provide facility for highlighting apparatus, such as flagging and parra-webbing to be erected. The loops may also be conveniently used as hooks for use in pulling the cover over and away from the pit and out of backfilled ground if need be.

[047] In an alternative embodiment, the lid 34 is removably fastened to the connecting panel 52 and through it and strip 54 to front wall panel 46. The lid is thereby entirely removable from the vertical walls. Fastening may be by zipper or further hook and loop fasteners, stitching and the like.

[048] In a further embodiment, additional fastening means in the form of stitching or zippers are provided to connect the lateral peripheral portions 68a, 68b of membrane 34 to the adjacent side panels 48, 44 respectively.

2019101123 27 Sep 2019 [049] Instead of zippers, other fastening means may be employed without departing from the scope and spirit of this invention. Non-limiting examples include a hook and loop strip system or mating studs of known design. In the case of the lid assembly, hinge connectors may be employed to connect it with wall 46 with or without connecting strips 52, 54 in the embodiment of Figures 1 to 4.

[050] Referring to Figure 5 and Figure 6, alternative embodiments of the invention cover are shown applied to pits of differing shape, namely a side entry pit in Figure 5 and a flat-topped pit in Figure 6. Like parts are like numbered in Figure 5 but in Figure 6 are increased by a hundred. In cover 100, side wall panel 144 therefore corresponds to wall panel 44 in Figures 2-5 but is rectangular to accommodate a rectangularly walled pit, instead of a stepped pit of the kind shown in Figure 1. Loops 72 are unchanged in Figure 6. In both cases illustrated, the lid 34, 134 is in partly open or partly closed position, exposing cavity 18, 118 within, for inspection or access for performance of work by site personnel.

[051] The flat top of lids 34,134 provide surface area on which to display safety signage or other notifications.

[052] Another feature of the pit protection system is that once it has been placed in operative position over the pit the lid can be raised and access obtained, whether for inspection of the pit internally or for further work to be completed within. After such task has been performed, the protective plate is then returned to its sleeve and the cover closed. This can be performed multiple times.

[053] Figure 7 illustrates the cover of the invention in plan view with the reinforcing board 180 removed in (a) and replaced in its sleeve defined by straps 176 in (b). When replaced, the board extends entirely across pit cavity 18 and rests on the opposite rims of both pairs of side wall sections 112.

[054] Although the term “fold lines” has been used in describing the preferred embodiment of the invention, this has been for convenience of describing the parts constituting a cover blank cut from a single piece of fabric. Such lines need not be specifically formed in manufacture. However, through use, they are likely to develop in the fabric to at least some extent. It will be appreciated that to

2019101123 27 Sep 2019 accommodate pits of different shapes and dimensions, the cover of the protection system will be shaped and sized accordingly and any fold lines positioned correspondingly.

[055] In a further embodiment of the invention, the lid is not formed of a double sheet of fabric, but has supporting webbing on the inside surface to support the rigid plate against it when the lid is lifted. The plate will span the gap defined by the pit and rest on opposite walls 14 when the lid is placed in closed position. The webbing may take the form of straps or may comprise a mesh or netting. It is also within the scope of the invention to attach the lid panel to the plate using suitable fastening means. These may include engagement means requiring complemental paired formations or devices where a first member of the pair is secured to the fabric panel and the other to the plate. Non-limiting examples include studs, hookand-loop fasteners, bolts and threaded sockets, hooks and eyes, and sliding rails.

[056] It is within the scope of this invention that instead of manufacturing the cover as a single piece of fabric, the cover may be assembled from two or more fabric panels such as those defined by the above fold lines. These separate panels will then be joined together using known techniques. By way of example, the cover shown in Figure 2 may be formed from two pieces that are stitched or zipped together. The first piece for example may be made up of the panels 42 and 44 and their respective upper and lower peripheral folding out sections56, 58 and 62. The second piece for example may be made up of the panels 46 and 48 and their respective upper and lower peripheral folding out sections 60, 62 and cover 34 with connecting pieces 52 and 54. In another embodiment, cover panel 34may be provided as a separate section for connecting to panel 54. It will be appreciated that numerous configurations may be selected.

[057] Preferably, at least the side panels 42, 44, 46 and 48 are of fabric coloured for high visibility. Ideally, the entire cover is so coloured.

[058] These embodiments merely illustrate particular examples of the pit covering assembly of the invention providing means for the temporary covering of a pit structure during construction works such as roadworks. With the insight

2019101123 27 Sep 2019 gained from this disclosure, the person skilled in the art is well placed to discern further embodiments by means of which to put the claimed invention into practice.

Claims (5)

1. A temporary in-ground pit cover comprising a flexible wall membrane vertically disposable in use to surround an in-ground pit from an upper open end thereof to at least a level of surrounding ground and, attached to at least a portion of the wall, a lid membrane disposable horizontally to cover the pit and adapted for operative association with reinforcing means for preventing a human falling into the pit, wherein the lid membrane comprises a peripheral portion defined by more than one strip portion extending from the lid membrane and overlapping the wall membrane when the lid is in closed position.

2. A cover of claim 1, wherein the reinforcing means comprises a rigid structure of generally flat proportions that is a plate or sheet, a set of parallel bars, or a grille, grid or mesh, wherein the rigid structure is capable of supporting an adult human's weight.

3. The cover of claim 1 or claim 2, wherein the lid membrane is adapted to be associated with the reinforcing means by comprising a structural feature for receiving the reinforcing means, wherein the structural feature comprises a sleeve that is accessible from an inside surface of the cover.

4. A method of temporarily barring ingress of foreign matter to a pit structure comprises the steps of providing a cover according to any one or more of claims 1 to 3, placing the cover in operative orientation over the pit and bringing the lid to closed position.

5. A kit for providing a temporary in-ground pit cover, the kit comprising a flexible wall membrane vertically disposable in use to surround an in-ground pit from an upper open end thereof to at least a level of surrounding ground and a lid membrane disposable horizontally to cover the pit and adapted for operative association with reinforcing means for preventing a human falling into the pit, wherein the lid membrane comprises a peripheral portion defined by more than one strip portion extending from the lid membrane and overlapping the wall membrane when the lid is in closed position.