GB2282400A

GB2282400A - Manhole security locking cover

Info

Publication number: GB2282400A
Application number: GB9417391A
Authority: GB
Inventors: Gordon Ford; Terence O'flynn
Original assignee: Duct & Access Covers Ltd
Current assignee: Duct & Access Covers Ltd
Priority date: 1993-09-29
Filing date: 1994-08-30
Publication date: 1995-04-05
Also published as: GB9320094D0; GB9417391D0

Abstract

Secondary cover apparatus for location in a manhole, beneath an existing manhole cover comprises a pair of support angles 14, 16 for attachment to opposed inner walls of the manhole to provide a pair of support edges for a secondary manhole cover comprising three cover plates 54, 56 (58, Fig.6). Two of these plates 54, 56 provide side plates which engage key-ways in one of the support angles to enable the side plates to be slid into position. A third plate provides a central plate (58, Fig.6) for subsequently positioning between the two side plates and which can be locked to one of the angles to prevent removal of the plates. Also disclosed are apparatus for installing the support angles 14, 16. The apparatus comprises a pair of support bars (18, 20 Fig.1) arranged to be supported on an upper surface of the manhole. Each support bar comprises a pair of adjustable clamp members (42, 44 Fig.4) for holding the support angles in position prior to securing them to the manhole wall. <IMAGE>

Description

MANHOLE SECURITY LOCKING COVER The present invention relates to covers for manholes, drains and the like. In particular, the invention relates to a secondary security covers for use with telecommunication and cable T.V. manholes and to apparatus and a method of installing such covers.

Existing manhole covers, though heavy and normally requiring a special key, can be accessed by unauthorised persons, such as vandals who may wish to damage the contents of the manhole. This is a particular problem for all contents but more so for telecommunication cables and this can cause considerable disruption to the telecommunication service and the cost of the damage can be considerable.

Existing manhole covers are generally in the form of a metal plate which can be circular, rectangular or any other suitable shape which fits into a recess in the road or ground so as to lie flush on the surface. The cover can be accessed by the authorised persons of the responsible body using a special key. It is not unknown for such keys to be acquired by vandals who use them to remove the covers and damage the contents of the manhole.

An object of the present invention is to provide a security device for a manhole which restricts access of a vandal or an unauthorised person to the interior of the manhole if the manhole cover is removed.

Another object of the present invention is to provide a secondary manhole cover for installation into the manhole beneath the existing cover for acting as a secondary deterrent to unauthorised accessors.

A further object of the invention is to provide a secondary cover which can be readily and easily installed into an existing manhole without affecting the operation of the existing cover and without restricting access to the manhole by authorised personnel.

According to a first aspect of the present invention there is provided secondary cover apparatus for location in a manhole beneath a primary manhole cover, the secondary cover apparatus comprising; secondary cover supporting means for securing to the side of the manhole, the secondary cover supporting means being arranged to support a secondary manhole cover to substantially prevent access to the manhole if the primary manhole cover is removed; and a secondary manhole cover arranged to be removably fitted to the secondary cover supporting means, the secondary manhole cover and the cover supporting means having respective cooperating elements arranged to receive locking means to enable the secondary manhole cover to be locked to the secondary cover supporting means.

Preferably, said secondary cover has means, for example a housing, for protecting said locking means when in the secured position.

The secondary cover supporting means may be provided by two cover supports, arranged to be located on opposite sides of a manhole, one cover support having key ways for receiving corresponding key elements on said secondary cover.

In one embodiment the secondary cover is provided by a single cover which is fitted on top of the secondary cover supporting means. The locking means may be a padlock which locks around a staple secured to the cover supporting means and which protrudes through a slot in the cover.

In other embodiments of the invention the secondary manhole cover is provided by a plurality of separate elements. For example the cover may comprise two of said cover elements arranged to be fitted to cover support angles, providing the cover supporting means, by locating the side covers over key ways in one of the angles so that the cover can slide relative to the cover supporting means.

The secondary cover may alternatively be provided by two side covers and a central cover. In order to locate the secondary cover, the side covers are first engaged with the cover supporting means and are slid to either side of the manhole. The central cover is then fitted onto the cover supporting means which has a slot for receiving a staple on one of the cover supporting means so that, when the central cover is in place, the central cover and the side covers can be locked by a padlock securing the staple. The central cover may have a welded or otherwise secured housing unit for covering the hasp to prevent access by vandals and the like attempting to saw or damage the padlock.

Preferably, the central cover has coupling means arranged to co-operate with one of the cover supports so that the cover can be located between the side covers once installed, and the central cover has means co-operating with the other cover support to create a lockable element adapted to receive a locking means such as a padlock. The cover plate has a housing element welded or otherwise fastened thereto above the padlock to prevent access by vandals and the like.

In an alternative embodiment of the invention, a single locking plate similar to the central locking plate is used when the manholes are of smaller or squarer shape. Two cover supports are still required and the central locking cover is fitted on to one of the cover supports, as with the multiple-cover locking plate, and the other side of the single locking plate is fastened to the other cover support with a padlock and the like as described above.

According to a second aspect of the present invention there is provided security cover installation equipment comprising a framework of two horizontal bars which are arranged to be secured to secondary cover supporting means comprising a pair of cover support angles, each horizontal bar having one fixed and one horizontally adjustable threaded adjustment bar and each threaded adjustment bar having a fixing angle clamp.

In use, the secondary cover support angles are secured between the two the horizontal bars using the angle clamps and the support angles are then lowered into the manhole.

The height of the support bars or the depth of the support bars from the manhole surface is set by adjusting the threaded bar using a handwheel at the top of each bar.

Levelling of the horizontal support bars are achieved by using a spirit level. When each cover support angle is located at the proper depth and is levelled, it can then be secured to the manhole wall by expanding bolts or power anchors or the like.

When the secondary cover is so fitted, it does not have a specific shaped key in order for it to be breached. It will require firstly the vandal to break the housing cover, then the padlock and then remove the units; this acts as a substantial deterrent to most vandals who do not normally carry the necessary equipment.

The outer locking plates and the central locking plate have lifting handles which may be retractable, if required.

According to a third aspect of the present invention there is provided a method of installing a security cover in a manhole beneath a removable manhole cover comprising the steps of: removing the existing manhole cover; lowering at least two separate security cover support means into the manhole; securing the cover support means to the sides of the manhole; fitting at least one removable lockable cover plate to said support means; and locking said lockable cover plate to one of said support means, using locking means.

These and other aspects of the invention will become apparent from the following description, when taken in combination with the accompanying drawings in which: Fig. 1 is a plan view of a manhole with the cover removed with secondary cover support positioned for installation; Figs 2a, 2b and 3a and 3b are longitudinal side and end views respectively of the cover supports shown in Fig. 1; Fig. 4 is an isometric view of part of Fig. 1 showing a single installation bar coupled to the cover supports.

Fig. 5 is a view of a manhole with the secondary cover support shown installed and side covers of a first embodiment of a secondary cover being shown fitted on to the cover supports; Fig. 6 is a view similar to Fig. 5 with the side plates in location and a central locking plate fitted between the side plates to provide complete secondary cover; Fig. 7 is a sectional view taken on the lines 7-7 of Fig. 6; Fig. 8 is a sectional view taken on the lines 8-8 of Fig. 6; Fig. 9 is a plan view through a modified version of the secondary cover of Figures 6 to 8, and Fig. 10 is a cross-sectional view of the central plate, and parts of the side plates, of the secondary cover of Fig.

9.

Reference is first made to Figs. 1, 2 and 3 of the drawings. Fig. 1 shows a manhole generally indicated by reference numeral 10 which has an existing rectangular frame section 12 for receiving a manhole cover, not shown in the interests of clarity. In this embodiment the manhole is based upon a British Telecom Reference No. 6 which has a clear opening of 1308 x 613 mm. The manhole has straight sides and in order for a secondary security cover to be installed, a supporting frame for the security cover must be secured to the sides of the manhole. This is achieved by using cover support angles 14,16 which are secured to opposite sides of the manhole 10, as shown in Fig. 1.The support angles are positioned and levelled using security cover insulation equipment, generally indicated by reference numerals 18 and 20 and which will be described in more detail hereafter with reference to Fig. 4.

The secondary cover support angle 14 is an L-shaped bar with a plurality of holes 20 disposed along its length to enable the support to be secured to the side of the manhole when at the desired position. The top flat surface 22 of the support angle 14 is continuous.

Support angle 16 is of generally similar dimensions to support 14 and also has a plurality of holes 20 to enable the support to be secured to the opposite side of the manhole, e.g. by way of bolts. However, the top flat surface 24 has four cutouts 26 which allow cover plates of the security cover to be fitted to the shelf supports, as will be later described in detail. A staple 28 is welded to the top surface 24 for co-operating with a slot in a central locking plate as will be described to allow the secondary cover to be secured in the manhole to the cover supports.

Reference is now made to Fig. 4 of the drawings which depicts an isometric view of one horizontal support bar 18 of the two shown in Fig. 1 for positioning the shelf support structures 14 and 16 at a desired depth and level within the manhole 10. Only one horizontal bar 18 will be described in detail but it will be appreciated that the structure and operation of the other horizontal bar is identical.

The horizontal bar 18 has a longitudinal slot 30 therein and a fixed aperture 32 for receiving threaded bars 34 and 36 respectively. Threaded bars are connected to respective handwheels 38,40 at their upper end and the bars each have a fixing clamp 42,44 at the lower end for receiving the horizontal section of the respective cover support angles 14 and 16 respectively. As shown in Fig. 1, each support angle 14,16 is coupled to two horizontal bars 18 and 20 by which means the horizontal bars can be lowered into the manhole opening 10.

When the cover support angles 14 and 16 are so clamped, they can then be installed in the manhole to allow installation of the security cover. This is achieved as follows: each horizontal support bar is laid across the opening, usually about 300-500mm from each end with the fixed threaded bars to the same side; the adjustable threaded bar 34 is moved to suit the clear opening of the manhole. One support angle, for example 14, is fed into the jaws of the clamp 44 to one side and tightened by hand using the clamp bolt 46. This reduces the risk of the support angle falling inside the manhole and potentially causing damage to cables. This is repeated for the other support angle 16.Once the support angles 14 and 16 are clamped, the installer uses a spirit level and tape measure to level and align the support angles 14,16 with each other, using the hand wheels 38 and 40 to adjust for height. Once the support angles are at the desired position, they can be secured to the manhole walls 48 and 50 respectively using bolt 52, only one of which is shown, or any other suitable fastener. Once a minimal number of fixings has been used to secure each cover support to the manhole walls, the installation equipment is removed.

Reference is now made to Figs. 5-8 of the drawings which will depict the installation of the secondary cover on top of the cover support angles 14,16. Once the cover support structure, that is the two support angles 14 and 16, is secured at the desired depth and is levelled, the security cover is fitted. In this embodiment the security cover consists of three cover plates; two outer locking plates 54 and 56 respectively which are best seen in Fig. 5 and a central locking plate 58 as best seen in Fig. 6. The outer locking plates 54 and 56 are identical and are generally rectangular with each having a pair of lifting handles 60 and 62 respectively on their top surface. The lifting handles 60,62 are shown projecting clear of the top surface of the plate but these handles may also be retractable.Each outer plate 54,56 has four generally Lshaped lugs 64 disposed beneath each corner and two generally L-shaped lugs 66 disposed beneath one side. The positioning of the lugs 64 and 66 means that plates 54 and 56 are interchangeable and can be used as either the right or left plate.

In order to install a plate in the manhole, the plate is lowered by the lifting handles so that the lugs 64 mate with the top surface 22 and the plate is then moved in the direction of the arrow as best seen with reference to the left plate in Fig. 5. Care is taken to ensure that the lugs 64 are opposite the cutouts 26 so that when the plate is moved in the direction of the arrow, it lies flat on the supports 14 and 16. When in a supported position, which is best seen with reference to the right-most plate 56 shown in Fig. 5, the plate is then moved either to the right or the left so that the lugs 64 engage with top surfaces 22 and 24 of supports 14 and 16 respectively. When the locking plates 54 and 56 are so installed and moved as far as they can go to the outside of the manhole cover as best seen in Fig. 6, the central locking plate 58 is then be installed.

It will be appreciated that when the covers 54 and 56 are in their outer position, they cannot be removed by using lifting handles 60 and 62 respectively because of the interaction of lugs 64 and the top surfaces 22 and 24 of the shelf support structures.

The central locking plate 58 has only two lugs at one corner, generally indicated by reference numeral 70, and the central plate is installed so that these lugs pass under the top surface 22 of support 14 and the central plate 58 is then lowered into the position shown in Fig. 6. It will be appreciated that the central plate has an aperture 72 for receiving the staple 28 of the shelf support 16 and when the central plate is installed, the staple 28 projects through the slot, as best seen in Figs. 7 and 8 of the drawings.

It will also be noted that the central locking plate is wider than the outer locking plate and is fitted so that sides 74 and 76 abut the sides of each side locking plate and it has a cover portion 78 and 80 at each side to cover the join or abutment, as best seen in Fig. 7 of the drawings.

When the central locking plate 58 is installed so that all the plates are in position, as shown in Figs. 6, 7 and 8, a padlock is then fitted to the staple 28 to secure the entire cover in position. The padlock may be protected by a cover 82 which prevents access to the padlock by saws, jemmies or the like, to provide a high security seal.

Therefore, once the cover is installed, as shown in Figs. 6 and 7, and padlocked it provides a secondary antivandal cover with use with manholes. It will be appreciated that although this cover is described for use with a standard British Telecom manhole it could equally be applied to any other suitable sized manhole with the dimensions of the cover support and covers being changed accordingly In addition, it will be appreciated that the handles of each cover may be fixed or retractable depending on requirement. The secondary cover could be used in gas or sewage manholes or any other manhole where a secondary protection system is required to deter vandals or unauthorised personnel who wish access to the manhole.

There is shown in Figures 9 and 10 a modification of the central locking plate 58 described above with reference to Figure 6 and which enables the secondary cover to fit snugly into the manhole. The modified central plate 58a is used in conjunction with the two outer locking plates 54, 56 described above and is substantially as the central plate 58 described above except that an adjusting bolt 84 is provided in each of the four lugs 90. Each bolt extends substantially horizontally through the vertically extending leg 88 of the corresponding lug 90 and can be adjusted via nuts 92a,b to vary the distance at which the bolt extends from the lug 90.

In order to assemble a secondary cover incorporating such a central plate 58a, the same procedure as is described above is followed. Additionally, after an initial positioning of the central cover 58a, that cover is then removed and the adjustment bolts 84 adjusted so that when the central cover is refitted the bolt heads 94 abut respective adjacent lugs 96 fitted to the side covers 54,56, so tightening the fit of the central cover. This process may require to be repeated a few times to produce the optimal fit.

It will be appreciated that various modifications may be made to the embodiments hereinbefore described without departing from the scope of the invention. It will be appreciated that the padlock cover 82 can be omitted when very high quality padlocks, such as Ingersoll CS700 extra close shackle, are used. In addition, a single cover plate may be used instead of the three covers or a central cover plate and a single outer cover could be used depending on the dimensions and requirements of the manhole. In this regard, the single cover would be substantially the same as the central cover 58 except that it would not require to have the overlap plates 78 and 80. The cover plate and supports are made of galvanised steel.It will be appreciated that the cover plates and supports may be made of any suitable material, such as mild steel, stainless steel or plastic or a combination of metal, plastic, aluminium or the like.

A particular advantage of the present invention is that the security covers can be manufactured and retrofitted to existing manholes to provide an added level of security and can, of course, be used and installed when creating new manholes to ensure a higher level of security from the outset. A further advantage of the invention is that even if the vandal or intruder has a particular key to remove the manhole cover, he is not able to gain access to the manhole unless he is able to break the padlock seal on the secondary cover and this, of course, provides a much higher level of deterrent than simply the manhole cover itself. A further advantage of the invention is that the use of the two supports means that the cover can be readily and quickly installed in a variety of manholes and the cover plate or plates can be simply dropped in place and slid along to ensure rapid installation of the cover. The installation equipment ensures that the cover supports are clamped prior to lowering into the manhole to minimise the risk of supports falling inside the manhole and potentially causing damage to cables, pipes and the like. A further advantage is that once the cover plates are removed, the shelf support structures intrude by a minimal amount into the manhole and do not essentially restrict access to the manhole by users for normal maintenance and operation.

Claims

1. Secondary cover apparatus for location in a manhole beneath a primary manhole cover, the secondary cover apparatus comprising; secondary cover supporting means for securing to the sides of the manhole, the secondary cover supporting means being arranged to support a secondary manhole cover to substantially prevent access to the manhole if the primary manhole cover is removed; and a secondary manhole cover arranged to be removably fitted to the secondary cover supporting means, the secondary manhole cover and the cover supporting means having respective cooperating elements arranged to receive locking means to enable the secondary manhole cover to be locked to the secondary cover supporting means.

2. Apparatus according to claim 1, wherein the secondary cover supporting means comprises a supporting ledge arranged to be located in a manhole below the primary cover and to extend about at least a portion of the inner wall of the manhole.

3. Apparatus according to claim 2 for use in a manhole cover with substantially rectangular cross section, wherein the supporting ledge comprises a pair of cover support arranged to be located on opposing inner walls of the manhole.

4. Apparatus according to claim 3, wherein the two cover supports are arranged to be secured to the inner walls of the manhole by means of bolts.

5. Apparatus according to claim 4, wherein at least one of the cover supports has key-ways therein for receiving corresponding key elements of the secondary cover for the purpose of positioning the secondary cover with respect to the secondary cover supporting means.

6. Apparatus according to any one of claims 3 to 5, wherein the cover supports are provided by respective angle bars.

7. Apparatus according to any one of the preceding claims, wherein the secondary manhole cover comprises a plurality of cover portions.

8. Apparatus according to claim 7, wherein said cooperating element on the secondary manhole cover is provided on one of said plurality of cover portions, each cover portion comprising coupling means arranged to couple the portion to a neighbouring portion to prevent any one of the portions being removed when the locking means is in place.

9. Apparatus according to claim 7 or 8, wherein at least one of the cover portions comprises adjustable extension means arranged to abut a side surface of an adjacent cover portion, or an adjacent portion of the inner wall of the manhole or of the secondary cover supporting means, for enabling the secondary manhole cover to be fitted tightly into the manhole.

10. Apparatus according to claim 9, wherein the adjustment means comprises a plurality of adjustable bolts.

11. Apparatus according to claim 10, wherein the adjustment bolts are provided at the interface between adjacent cover portions.

12. Secondary cover apparatus substantially as hereinbefore described with reference to Figures 5 to 7 and Figures 5 to 7 as modified by Figures 8 and 9.

13. Apparatus for installing a secondary cover supporting means which supporting means comprises a pair of angle bars for mounting on opposite side walls of a rectangular manhole cover, the apparatus comprising a pair of support bars arranged to be supported on an upper surface of the manhole substantially parallel with one another, each bar supporting a pair of spaced apart adjustment members which extend parallel to one another and at right angles to the bar into the manhole when the apparatus is in use, each adjustment member having securing means at an end thereof, remote from the bar, for engaging one of the angle bars, the spacing between the securing members and the corresponding support bar and the spacing between each pair of adjustment members supported on the same bar being variable to enable the precise positioning of the angle bars in the manhole prior to securing of the angle bars to the inner wall of the manhole.

14. Apparatus according to claim 13, wherein the adjustment members each comprise a threaded bar rotatably mounted in the corresponding support bar, the securing members threadably engaging corresponding ones of the threaded bars.

15. Apparatus according to claim 13 or 14, wherein one of the adjustment members supported by each support bar is slidably mounted in the support bar to enable the horizontal positioning of an angle bar supported by the securing member attached to that bar.

16. Apparatus for installing a secondary cover substantially as hereinbefore described with reference to Figures 1 to 4 of the accompanying drawings.

17. A method of installing a security cover in a manhole beneath a removable manhole cover, the method comprising the steps of: removing the existing manhole cover; lowering at least two separate security support means into the manhole; securing the cover support means to the side of the manhole; fitting at least one removable lockable coverplate to the support means; and locking the lockable coverplate to one of the supporting means using locking means.

18. A method of installing a security cover substantially as hereinbefore described with reference to Figures 1 to 8 of the accompanying drawings or to Figures 1 to 8 as modified by Figures 9 and 10.

Amendments to the claims have been filed as follows 1. Secondary cover apparatus for location in a manhole beneath a primary manhole cover, the secondary cover apparatus comprising; secondary cover supporting means for securing to the sides of the manhole, the secondary cover supporting means being arranged to support a secondary manhole cover to substantially prevent access to the manhole if the primary manhole cover is removed; and a secondary manhole cover arranged to be removably fitted to the secondary cover supporting means, the secondary manhole cover and the cover supporting means having respective cooperating elements arranged to receive locking means to enable the secondary manhole cover to be locked to the secondary cover supporting means.

12. Secondary cover apparatus substantially as hereinbefore described with reference to Figures 5 to 7 and Figures 5 to 7 as modified by Figures 9 and 10.