Field of the Invention

The present invention concerns improvements to tiltable support structures. Specifically, but not exclusively, the present invention concerns an improved tiltable street lamp and a tiltable supportive post assembly for/of a street lamp, security camera or other overhead-supported electrical device.

Background to the Invention

Installation, maintenance and replacement of street lamps and overhead security cameras is a substantial area of industry that employs many hours of time and involves considerable costs. The industry faces a number of special practical problems and constraints and which has led to on-going substantial changes in design over the past several decades.

In general, for overhead-supported electrical devices such as street lamps and security cameras, the lantern, camera or other electrical device is held at the upper end of a support column/ pole that commonly is a metal tube of the that rises several metres high (often 4 to 8 metres) above the street/ area of installation. Commonly it is necessary for power and/or signal electrical wiring/ cabling to be delivered into the column/pole through the ground at the base. The base of the support column/ pole is itself normally rooted over half a metre (or much more) into the ground, often having to be cemented in place, to stabilize the tall column/ pole.

The above-ground base of the column and the under-ground root are commonly relatively broad to enhance upright stability and the base is often broad for the first metre- or-so above ground to further provide an accessible chamber housing a control box or circuit board with controls, cut-out fuses or the like for managing the power and/or signal passing to/from the lamp/ overhead-supported electrical device. In many cases the base has a relatively broad diameter circular cylindrical form and in other cases it is box-shaped forming a cabinet for the control box or circuit board. Access to these electronics in the base chamber is normally provided by an opening with a door in the base. The door is normally weather-sealed and secured closing the opening, by use of a special tool- operated latch/lock.

To facilitate subsequent access to the elevated parts - the lantern of the street lamp or the camera of the pole-supported camera installation - it is nowadays relatively widespread practice to incorporate an above-ground hinge into the upright support column/ pole. This hinge is usually either at a transverse (substantially horizontal in use) break in the upper tubular pole or at the foot/base closer to the ground using a longitudinally split clam-shell opening arrangement of the base. In street lamps the hinge allows the street lamp to be tilted via the hinge between the substantially upright operative state with the lantern suspended high overhead and a lowered state with the majority of the support column/ pole lowered to be substantially parallel to the ground and with the lantern at around waist-height of the service engineer or lower so that it can be readily accessed for maintenance or replacement. For the heavier duty street lamps and pole- supported cameras the lone service engineer may need to be assisted by a counterbalance unit having a winch, or a compression spring or having a hydraulic cylinder.

In the present applicant’s original street lamp and supportive post assembly system, as illustrated in patent application PCTWO2015082934, a hinged connector assembly functions as an above-ground basal part of the support column/ pole of a street lamp. The unique hinged assembly has orientational adjustability to select the direction that the lantern faces in relative to the base’s door and the assembly can be very economically deployed as a retro-fit to an existing street lamp’s base avoiding the need for new excavation work when an existing street lamp and post needs to be upgraded/replaced.

The general form of the hinged connector assembly from PCTWO2015082934 is illustrated in Figures 1 and 2. The assembly has multiple parts. It comprises a tubular metal over-sleeve 1a that can slide down over an existing lamp post base 1 b, a cap 5 that is placed on top of the lamp post base 1b and which is held in place radially relative to the sleeve and the sleeve relative to the lamp post base 1 b. The cap 5 is topped by a toothed disc 4 that functions as the lower in use part of the hinge and which aligns with and radially keys to the over-sleeve 1a. Over this is the hinge bracket 3 that is the upper part of the hinge and which incorporates a central socket for support pole 10. The whole assembly is then enclosed from above by a conical lid 2 that is slid down the pole to cover the hinge connector.

We have found that the existing tiltable support structures are not optimally compact and cost-efficient to manufacture and distribute. Furthermore, with more compact designs there is commonly a compromising trade-off between having a least manufacturing cost, modularity of manufacture, optimal robust upright stability and also in still having enough door access to the base chamber of the structure for ease of maintenance of the electrical componentry housed in the base. In some of the tiltable structure designs, base access instead relies primarily on clam-shell style opening up of the base when the pole is tilted down, but this has its own problems and does not optimize quick access for the engineer to the base’s electronics without taking the steps of lowering the pole first.

It is a general object of the present invention, inter alia, to provide an assemblage that is generally more cost-efficient, more space-efficient and easier to assemble and operate than the existing hinged support assemblies.

Summary of the Invention

According to a first aspect of the present invention there is provided a tiltable support structure for an overhead-supported electrical device, the structure comprising: i) a tubular support pole or column for supporting the electrical device at or near an upper in use end thereof; ii) a tubular base that is broader than the pole or column and defining a chamber therewithin suitable for housing electronics for the electrical device in use, the base having a lateral opening in a sidewall with a door for access to within the chamber; and iii) a hinged connector for pivotally inter-connecting the pole and the tubular base so that the pole may be tilted from an upright state to a lowered state, wherein the hinged connector has an upper in use hinge part and lower in use hinge part that are pivotally connected together by a pivot pin, the upper in use hinge part having a central axial socket for holding the pole and the top of the upper in use hinge part having a downwardly broadening funnel-shaped form. Preferably the tubular base has a polygonal form with a plurality of sidewalls and corners as viewed end-on of the tube. Particularly preferably the tubular base is a tubular extrusion and its polygonal form is an approximately rectangular/ box section (suitably square) form with corners as viewed end-on; - but preferably the sidewalls thereof are not planar but are rounded outwardly/ are outwardly convex (the sidewalls appearing to bulge outwardly). This ‘rounded square’ arrangement has been found to be particularly effective for a combination of the desired space-efficiency, accessible internal capacity and strength for stability.

Particularly preferably the broadening funnel-shaped outer form at the top of the upper in use hinge part transitions to provide a downwardly inclined shoulder at its lower end, the hinged connector lower in use part having a polygonal form corresponding to the polygonal outer form of the tubular base to fit thereto and having a complementary inclined counter-shoulder against which the inclined shoulder of the upper hinge part rests when the support structure is assembled and in its upright state. We have found that this arrangement greatly improves cost economy of manufacture, minimising parts and amount of materials used yet while optimizing, not further compromising, both upright stability and the service engineer’s working access to the electronics within the chamber of the tubular base.

Particularly preferably the downwardly broadening funnel-shaped form is frusto- conical - or it may be polygonal, square or rectangular funnel-shaped, for example, suitably broadening from a circular cylindrical upper end that fits to a circular cylindrical said support pole. The funnel-shaped outer form of the upper hinge part is both an integral circumferential or lateral strut/ stabilizer for maintaining the pole upright and a cover to protect the electronics within the chamber from the weather. An elastomeric sealing ring is preferably further provided that mounts to the upper end of the upper in use hinge part to seal against the pole.

Particularly preferably the hinged connector lower in use part has a broad central aperture, occupying most of its area, and that accomodates the bottom of the pole-holding socket of the hinged connector upper part along with the bottom end of the pole when the pole is upright.

Preferably the hinge and pivot pin span substantially the full width of the broad tubular base, maximizing strength of the hinge. The pivot pin preferably is secured in place by a fixing (eg a grub-screw or bolt) that engages into a notch or socket part-way along the pivot pin and whereby the pivot pin may only be removed when the pole is lowered, opening the upper hinge part away from the lower hinge part.

Preferably the pivot pin is secured in place by a fixing that engages into a notch or socket part-way along the pivot pin and whereby the pivot pin may only be removed when the pole is lowered, opening the upper hinge part away from the lower hinge part to provide access to the fixing.

Preferably a plurality of sockets for a bolt or other fixing to secure the bottom hinge part to the base are provided on the lower hinge part, with one socket at each corner, and which are covered by the upper hinge part in use and whereby the fixings may only be accessed when the pole is lowered, opening the upper hinge part away from the lower hinge part.

Advantageously the lower hinge part may be secured by fixings to the tubular base at any one of a plurality of different orientations.

According to a further aspect of the present invention there is provided a tiltable support structure for an overhead-supported electrical device, the structure comprising: i) a tubular support pole or column for supporting the electrical device at or near an upper in use end thereof; ii) a tubular base that is broader than the pole or column and having a polygonal outer form defining a plurality of sidewalls and defining a chamber therewithin suitable for housing electronics for the electrical device in use, the base having a lateral opening in a sidewall with a door for access to within the chamber; and iii) a hinged connector for pivotally inter-connecting the pole and the tubular base so that the pole may be tilted from an upright state to a lowered state, wherein the hinged connector has an upper in use part and lower in use part that are pivotally connected together by a pivot pin, the upper in use part having a central axial socket for the pole with a funnel-shaped outer form at the top that transitions to provide a downwardly inclined shoulder form at its lower end, the hinged connector lower in use part having a polygonal form corresponding to the polygonal outer form of the tubular base to fit thereto and having a complementary inclined counter-shoulder outer form against which the inclined shoulder form of the upper hinge part rests when the support structure is assembled and in its upright state.

According to a yet further aspect of the present invention there is provided a counter-balance unit that is mounted in use onto the base length of a tiltable support structure for an overhead-supported electrical device, the counter-balance unit comprising a mounting cradle that mounts over a rear wall of the tubular base and with longitudinal side edge flanges that detain against left and right sidewalls of the base.

According to a yet further aspect of the present invention there is provided a counter-balance unit that is mounted in use onto the base length of a tiltable support structure for an overhead-supported electrical device, the counter-balance unit comprising a mounting cradle that extends down the base and a telecopic support arm pivotted to the lower end of the cradle and a gas strut or other resilient biassing means pivotted to the upper end of the cradle and the lower end of the gas strut or other resilient biassing means is pivotted to a point in the lower half of the support arm. Brief Description of the Drawings

Figure 1 is an isometric frontal view of the applicant’s own prior art tiltable street lamp assembly; and

Figure 2 is an exploded assembly view of the street lamp arrangemen in Figure 1.

A preferred embodiment of the present invention will be now more particularly described hereinbelow by way of example with reference to the accompanying drawings wherein:

Figure 3 is a front elevation view of the preferred embodiment of tiltable support structure as installed in its operative erect state - showing the pole (upright as in use), the hinged connector and the fuse/control-housing base above-ground and further showing the root below the ground-level anchoring the structure;

Figure 4 is a close-up view of the top of the fuse/control-housing base, with the upper and lower parts of the hinged connector closed together and the upper part further acting as a lid to the chamber of the base and as a lateral stabilizer;

Figure 5 is an isometric view of the tiltable support structure in a partially lowered state showing the upper and lower parts of the hinged connector opening apart (the lowering of the pole being with the assistance of a gas strut counter-balance that extends down bisecting the angle between the pole and the base);

Figure 6 is an exploded assembly view of the tiltable support structure of Figure 4;

Figure 7 is a close-up side elevation view of the hinged connector of the tiltable support structure, showing it in the closed (pole upright) state;

Figure 8 is a close-up side elevation view of the hinged connector of the tiltable support structure, showing it in the open (pole lowered to horizontal) state;

Figures 9A-E are views of the upper part of the hinged connector, respectively from top plan, isometric frontal, front elevation, right side elevation and bottom plan; Figures 10A-E are views of the lower part of the hinged connector, respectively from top plan, isometric frontal, front elevation, right side elevation and bottom plan;

Figure 11 is a top plan view of the distinctively-shaped ‘rounded-square’ tubular base of the tiltable support structure;

Figure 12 is a trio of views of a top hinge seal for the assembly, the views comprising a top plan view, a side elevation view and a transverse sectional view;

Figure 13 is a top plan view of a root-protective sheath adapted for ensheathing and protecting a below ground root length of the tubular base;

Figures 14A-E are close-up views of the hinged connector region of the tiltable support structure, with the specially designed counterbalance unit fitted, respectively from isometric frontal view, rear elevation and right-side elevation in upright state and then right-side elevation in partially lowered state and, finally, substantially fully lowered state.

Description of the Preferred Embodiment

Referring to Figures 3 and 4, the illustrated preferred embodiment of tiltable support structure is suitably a lamp post (street lamp), but may alternatively or additionally be a security camera or other overhead- borne electrical device. The lantern, camera or other device (not illustrated) is borne at the upper end of the upright support tubular pole 10, most commonly mounted projecting radially from the top of the pole 10.

The pole 10 is suitably a simple circular-cylindrical extrusion and for most purposes is preferably extruded of a metal such as aluminium or of a metal alloy such as steel. The pole suitably has a modest diameter such as of the order of 76mm (preferably within the range 50mm to 100mm for most duties).

The base 40 of the tiltable support structure is also tubular but it is considerably broader than the pole 10 (preferably approximately twice as broad) and suitably has a breadth of the order of 150mm (preferably within the range 100mm to 300mm for most duties). The tubular base 40 is preferably also extruded of a metal such as aluminium or of a metal alloy such as steel. The tubular base 40 is, however, not circular-cylindrical unlike the support pole 10, but rather has a polygonal outer form defining a plurality of sidewalls and providing a sizeable axial chamber therewithin suitable for housing electronics such as cut-out fuses, cable inter-connectors or control systems for the electrical device in use. The base 40 has a lateral opening in one of the sidewalls with a door 41 for access to within the chamber.

The lowermost portion of the tubular base 40, suitably approximately a 700mm (preferably within the range 500mm to 1m) lowermost length of the base 40, is adapted to serve as the anchoring root of the support structure buried in the ground. To that end it is ensheathed in a root-protective sheath 50 which substantially excludes ground-water, air, cement, acid and organic matter of the soil from damaging the extrusion. The sheath 50, as illustrated in transverse section/ end elevation in Figure 13, has a corresponding ‘rounded-square’ shape and close-fitting size to the tubular base 40 so that it slides over it and fits very snugly over it. The profile of the root-protective sheath 50 though essentially a rounded square matching the profile of the tubular base 40, has a small furrow 51a-d at each corner that provides just enough flex to the sheath to facilitate its sliding installation onto the base 40.

Referring to Figures 5 and 6, the pole 10 is tillable by being pivotally coupled to the tubular base 40 by a unique form of hinge connector interface and that comprises a specially shaped moulded/ cast upper hinge connector part 20 and lower hinge connector part 30. The upper hinge connector part 20 and lower hinge connector part 30 are held and pivotted together by an unusualy robust, thick and long metal (preferably steel) pivot pin 21. The pivot pin 21 is suitably cast or extruded to be about of the order of 15mm in diameter (preferably within the range 10mm to 20mm) and thereby able to comfortably support loadings of 4 tonnes from the weight of the supported pole 10 and its mounted lantern or other electrical device. It is suitably at least as long as the width of the base 40 and thus in the example of a 150mm diameter/ breadth of base is 150mm long or greater. Preferably the pivot pin 21 has a notch 21a mid-way along its length so that it may be secured in place in the hinge by a grub-screw or the like screwed into the notch. It may suitably also have a notch, dimple or other feature at each end to facilitate secure attachment of a cradle of a counter-balance unit as will be described later below. The hinged connector upper part 20, as best seen in Figures 6 to 9, is a unitary moulding/ casting, most preferably of aluminium, that has a central axial tubular socket 22 for the pole 10 extending centrally down from its top end to its bottom end. Externally it has a frusto-conical form 23 that is contiguous with the annular top rim 22a of the central axial tubular socket 22. The frusto-conical form 23 extends downwardly and broadening radially outwardly to its lower end and transitions at its lower end to provide an inclined downward facing shoulder form 24. The shoulder 24 inclines from a high level at the rear edge of the connector forwardy and downwardly to a lower level at the front (as best seen in the side elevation views (Figures 7, 8 and 9D). In effect the frusto-conical form 23 is cut-away at a sloping angle at its left and right sides and rear giving a wedge-shaped cut out/recess into the sides and rear of the frusto-conical form 23 so that the form 23 may seat against a corrsponding sloping wedge form/shoulder of the hinged connector’s lower part 30. This enables the pole 10 in socket 22 to overlap with and into the hinge lower part 30.

The central axial tubular socket 22 is not only contiguous to the frusto-conical form 23 at the top rim 22a but also linked to it by an array of three strengthening/ stabilizing ribs/ webs 26a, 26b, 26c. Each of the webs 26a-c notably has in it at least one threaded hole 27 for a grub-screw or other fixing to be screwed into the exterior of the pole 10 to hold it firmly in place.

At the rear of the lower end of the hinged connector upper part 20 the moulding/ casting defines a hinge bracket arrangement comprising a cradle pair of sockets 25a, 25b through which the pivot pin 21 extends.

The hinged connector’s lower part 30, as illustrated in Figures 6 to 8 and 10, has a ‘rounded-square’ polygonal form, at least at its lower end, corresponding to the ‘rounded- square’ polygonal profile of the tubular base 40 to fit snugly to it. At its top/upper end it further has a complementary inclined counter-shoulder outer form 34 against which the inclined shoulder form 24 of the upper hinge part 20 rests when the support structure is assembled and in its upright state (see Figure 7). The hinged connector lower part 30 is also a unitary moulding/ casting, most preferably also of aluminium, that has at the rear of its upper end a complementary hinge socket 35a to inter-fit between the cradle pair of sockets 25a, 25b of the upper part 20 and through which the pivot pin 21 extends. A threaded hole 39 penetrates internally through hinge socket 35a to the bore of the hinge socket 35a and receives a grub-screw that can be tightened engaging into the notch 21a mid-way along the pivot pin 21 to lock the pivot pin 21 in place. This cannot be accessed from outside the assembly, so the pole must first be lowered to remove the pivot pin 21 .

The hinged connector lower part 30 has a pair of inclined bolt holes 38a, 38b, one extending downwardly and rearwardly at each side. These bolt holes 38a, 38b receive bolts from the hinged connector upper part 20 that extend through a pair of inclined bolt holes 28a, 28b, one extending downwardly and rearwardly at each side of the upper part 20, the bolts serving to lock the upper part 20 and lower part 30 closed together so that once erected the pole cannot be lowered by vandals. The bolts can suitably only be reached and operated with a special tool.

Referring to Figure 11, the rounded-square tubular base 40 has a screw-threaded socket 41a-d provided at each of its four corners to enable the hinged connector lower part 30 to be bolted in place to it. The hinged connector lower part 30 also has corresponding sockets 36a-d for bolts at each of its four corners, and which preferably are also screw-threaded. The geometry and arrangement of these and of the upper hinge connector part 20 and lower part 30 permits them to be positioned at any of four orientations relative to the sidewall 40a of the base 40 that has the door 41 . The hinged connector lower part 30 has an in-stepped skirt wall 30a that inter-fits snugly into the bore of the rounded-square tubular base 40. The skirt wall 30a has cut-outs at each of the corners corresponding to the overlying bolt holes 2 to accommodate passage of the bolts that bolt the connector lower part 30 to the base 40.

The hinged connector lower part 30 notably has a very broad central aperture, occupying most of its area, and that accomodates the bottom of the pole-holding socket 22 of the hinged connector upper part 20 along with the bottom end of the pole 10 when the pole is upright. This allows for a substantial length of the bottom of the pole 20 to be held in the constraing tube of the socket 22 giving enhanced upright stabilization to the pole 10.

The top of the tubular socket 22 is sealed to the outside diameter of the pipe 10 by a sealing ring 21 , that is suitably of an elastomer such as silicone. The sealing ring 21 preferably has an undulating, ribbed or corrugated internal bore for optimal grip to the exteror of the pipe 10 as illustrated in the transverse section view A-A of Figure 12.

Following the straight-forward assembly and installation of the tiltable support structure, the tilting down of the post 10 as required from time-to-time is simple to carry out and may be further facilitated with use of a special counter-balance unit 60 as shown in Figure 5 and Figures 14A-E. The counter-balance unit 60 has a mounting cradle 61 that mounts over the rear sidewall of the tubular base 40 and with longitudinal side edge flanges that detain against the left and right sidewalls of the base 40. The cradle 61 suitably mounts onto the pivot pin 21 and extends down the rear of the base 40 from the level of the hinge for about two thirds of the above-ground height of the base 40. A telecopic support arm 62 is pivotted to the lower end of the cradle 61 and has a roller 64 at its free end to roll up and down the pole 10, as the pole 10 is being raised or lowered. A gas strut 63 is pivotted to the upper end of the cradle 61 just below the hinge connector’s pivot pin 21 and the lower end of the gas strut 63 is pivotted to a point in the lower half of the support arm 62. The pressure in the gas strut is suitably adjusted to provide an optimal level of counter- balancing of the weight of the pole as it is raised and lowered. The gas strut 63 may be substituted with a hydraulic cylinder, compression spring or other resilient biassing means. The sequence of lowering of the pole 10 and the supportive operation of the counter-balance is shown in Figures 14C-E.