AU2003100630A4 - Cover Assembly - Google Patents

Description

04/08/2083 12:00 +61398867680 MORCOM PERNAT PAGE 1

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION INNOVATION

PATENT

"Cover Assembly" The following statement is a fll description of this invention, including the best method of performing it known to me: COMS ID No: SMBI-00363785 Received by IP Australia: Time 12:03 Date 2003-08-04 04/88/2003 12:08 +61398867600 MORCl1 PERNAT PAGE 86 2 COVER ASSEMBLY Field of the Invention This invenion relates to a cover assembly for an access port. In a particular non-linliting aspect it relates to a cover assembly which may be retrofitted to an existing access port for a sewerage or storm water line.

Background of the Invention Underground sewerage lines are generally provided with a number of access ports along their length to allow ongoing maintenance and monitoring of the line. Where the sewerage lines run under roads, the access ports are designed so that they have a heavy cast metal cover which fits into an in ground frame surrounding the mouth of the access port. The cover is generally arranged so that it sits flush with the road surface. Because these covers are very heavy as they are constructed of cast iron, they do not require any special fixing to the frame as the sheer weight of the metal is enough to hold the cover firmly in place.

Of course, one of the disadvantages of having such a heavy cover is that it can be very difficult to remove without specialized lifting equipment. Incorrect manual lifting of the cover can cause back injuries.

Furthermore, because of its great weight, the cover can prove to be relatively expensive. It may also not provide a very effective seal.

The invention seeks to provide a cover assembly which serves to obviate or ameliorate one or more of the disadvantages associated with conventional port cover systems. Preferably the cover assembly should be designed so that it can be retrofitted to existing access ports for sewerage or storm water lines.

COMS ID No: SMBI-00363785 Received by IP Australia: Time 12:03 Date 2003-08-04 04/08/2003 12:00 +6139987607 MORC OM PE RNAT PAGE 07 3 Disclosure of the Invention The invention provides in one aspect a cover assembly for an access port ending in an annular internally stepped in ground frame comprising, an annular insert having an upper rim, a central opening and a support step within the opening, the insert being shaped so as to fit within the in ground frame resting on an internal step of the in ground frame, and a circular cover member shaped so as to rest on the support step to close off the central opening.

Suitably the circular cover member is formed of cast metal. It may comprise cast aluninium, steel or alloys thereof.

The internal step of the insert may extend in a circle within the ground frame. There may be two or more such internal steps.

The support step may extend in a circle within the annular insert, The support step and cover may be constructed so that the cover member lies substantially flush with the upper rim of the annular insert when it is fitted within the insert.

Locking means may be provided to lock the cover member in place when fitted to the annular insert. The locking means may comprise a plurality of locking members projecting radially from the perimeter of the circular cover member into locking recesses formed in the armular insert. The heads of the locking members may also extend in the opposite direction into recesses provided in the cover member. They may comprise one or more screws, pins or bolts.

The cover member may include one or more recesses for assisting with removal of the cover members from the annular insert- The recesses may be formed with a lip to allow a tool to be inserted beneath the lift to apply a lifting force.

COMS ID No: SMBI-00363785 Received by IP Australia: Time 12:03 Date 2003-08-04 04/08/2083 12:880 +61398867600 MORCOM PERNAT PAGE 08 4 Sealing means may be provided to seal the opening. The sealing means may comprise a resilient annular sealing gasket interposed between the cover member and support step. The annular sealing gasket may be located in an annular recess provided in the support step.

The cover member may include means to lessen the likelihood that the sealing surface which bears upon the annular sealing gasket be damaged. Such means may comprise a circular flange of substantially lesser diameter than the circular cover member which depends from an underneath central region of the cover member. The purpose of the circular flange is to hold the sealing surface clear of the ground when the cover member is rested flat on the flange. In this way the risk of inadvertent damage to the sealing surface may be reduced.

Preferred aspects of the invention will now be described with reference to the accompanying drawings.

Brief Description of the Drawings Figure 1 shows a plan view of a cover member according to the invention; Figure 2 shows the cross section X-X taken through the cover member when fitted to a cover assembly according to the invention; and Figure 3 shows the cross section X-X of the cover member when fitted to an alternative cover assembly according to the invention.

Detailed Description of the Preferred Embodiments The various elements identified by numerals in the drawings are listed in the following integer list.

COMS ID No: SMBI-00363785 Received by IP Australia: Time 12:03 Date 2003-08-04 84/08/2003 12:80 +61398867600 MORCOM PERNAT PAGE 09 Integer List 1 Cover assembly 3 Annular insert 4 Bolt Upper rim 6 Recess 7 Central opening 9 Support step 11 Frame 12 Frame rim 13 Internal step 13a Internal step Cover member 16 Markings 17 Sealing gasket 19 Annular recess 21 Locking recess 23 Locking member 25 Cover recess 27 Plug 29 Lifting recess 31 Lip 33 Plug 35 Upper surface 37 Flange 38 Central hollow 39 Sealing surface Extended portion Referring to Figures 1 and 2 of the accompanying drawings, there is shown a cover assembly according to the invention generally designated 1.

COMS ID No: SMBI-00363785 Received by IP Australia: Time 12:03 Date 2003-08-04 OW4 Cia iaa L. b±I tM FUR&OM PERNAT PAGE 18 6 The cover assembly comprises an annular insert 3 which is fitted within a frame I I and held securely within the frame by the bolts 4.

s The amaular insert has an upper rim 5, which sits substantially flush with the upper surface 35 of the cover member 15 closing off the central opening 7 defined by the annular insert, The circular cover member 15 is provided with markings 16. It rests on a support iD step 9 extending in a circle around the interior of the annular insert 3. The support step includes an annular recess 19 for holding the sealing gasket 17 whereby to ensure an effective seal between the cover member and the annular insert.

The frame 11 which is typical of frames currently in place in access ports for sewerage systems, includes a frame rim 12 which in the case of Figure 2 is shown as being substantially flush with both the upper surface 35 of the cover member and the upper rim 5 of the annular insert.

The frame includes an internal step 13 for supporting of the bottom of the annular insert.

A locking reces 21, which may comprise an annular channel around the interior upper surface of the annular insert, serves to provide a means whereby the locking member 23 provided in the cover member may be projected to lock the cover member securely in place. The locking member may comprise a pin, screw or other projection.

The head of the locking member 23 may project into a cover recess 25 and the recess may in turn be covered by the plug 27.

COMS ID No: SMBI-00363785 Received by IP Australia: Time 12:03 Date 2003-08-04 04/08/203 12:00 +61398867600 MORCOM PERNAT PAGE 11 7 Lifting recesses 29 are also formed in the cover member. These include overhanging lips 31 rranged to provide purchase for a lifting tool inserted into the lifting recesses.

Plugs 33 are also used to cover the lifting recesses when not in use.

s The underneath of the cover member is provided with a centrally located annular flange 37 which extends below the body of the cover member. The purpose of the flange is to allow the cover member to be rested on the ground on top of the flange when the cover member is removed. The flange holds the sealing surface 39 of the cover member clear of the ground thereby reducing the risk of damage to the sealing surface.

A central hollow 38 is fomed in the cover member to reduce weight and also cost.

Referring to Figure 3, the cover assembly shown in this drawing is in most respects similar to that described with reference to Figure 2, The main diffrence between the two relates to the difference in height between the upper rim 5 of the annular insert and the frame rim 12. The purpose of having suqh a step is to account for situations where the cover assembly has been used to cover an access port in a road when the level of the road's surface has been raised from the original level which applied when the frame and access port were originally constructed. By using a deeper annular insert 3 as shown in Figure 3, it is possible to raise the level of the upper rim 5 and hence adjust for changes in the height of road surfbces.

Thus, the larger version of annular insert 3 includes an extended portion 40 which sits on a second internal step 13a forming part of the frame.

In the illustrated embodiment, this means that the bolts 4 lie within a recess 6 which is formed as a result of the addition of the extended portion. Otherwise, the functioning of the cover assemblies of Figures 2 and 3 are substantially the same.

Whilst the above description includes the preferred embodiments of the invention, it is to be understood that many variations, alterations, modifications and/or additions COMS ID No: SMBI-00363785 Received by IP Australia: Time 12:03 Date 2003-08-04 04/88/2063 12:00 +61398867600 MORCOM PFERNAT PAGE 12 8 may be introduced into the construotions and arrangements of parts previously described without departing from the essential features or the spirit or ambit of the invention.

It will be also understood that where the word "comprise", and vaiations such as "comprises" and "comprising", are used in this specification, unless the context requires otherwise such use is intended to imply the inclusion of a stated feature or features but is not to be taken as excluding the presence of other feature or features.

The reference to any prior art in this specification is not, and should not be taken as, an acknowlkdgment or any form of suggestion that such prior art forms part of the common general knowledge in Australia.

COMS ID No: SMBI-00363785 Received by IP Australia: Time 12:03 Date 2003-08-04

Claims (4)

1. 2. A cover assembly according to claim 1 wherein the internal step and support step extend in a circle within the respective in ground frame and annular insert and the cover member comprises an upper surface which lies substantially flush with the upper rim.
2. 3. A cover assembly according to claim 1 or claim 2 comprising a plurality of locking members which project radially from the perimeter of the circular cover member into locking recesses formed in the annular insert.
3. 4. A cover assembly according to any one of the preceding claims comprising a resilient annular sealing gasket interposed between the cover member and support step and a circular flange of substantially lesser diameter than the circular cover member depending from an underneath central region of the cover member.
4. 5. A cover assembly according to claim 1 substantially as hereinbefore described with reference to the accompanying drawings. Dated this 4th day of August 2003 Upwey Metal Products fpy Ltd by their patent attorneys Morcom Pernat COMS ID No: SMBI-00363785 Received by IP Australia: Time 12:03 Date 2003-08-04