EP1698826A1

EP1698826A1 - A street lamp assembly

Info

Publication number: EP1698826A1
Application number: EP05394008A
Authority: EP
Inventors: Sean Noone; Joseph Dee; Thomas Durkan; Thomas Brennan
Original assignee: Noontek Ltd
Current assignee: Noontek Ltd
Priority date: 2005-03-02
Filing date: 2005-03-02
Publication date: 2006-09-06
Also published as: WO2006092307A1

Abstract

There is provided a street lamp assembly (1). There is a hollow lamp column (2) mounting a luminaire (3) including a gas discharge lamp (4). Mounted within the hollow lamp column (2) is a microprocessor controlled ballast (5) and ancillary equipment (6) which could be, for example, communication nodes. The ballast (5) and ancillary equipment (6) may be housed within a sealed tube to allow the free passage of air through the hollow lamp column (2) past the tube or casing.

Description

Introduction

The present invention relates to a street lamp assembly comprising a hollow lamp column; a luminaire, having a lamp fitting therein for reception of a gas discharge lamp, mounted on the lamp column; and a microprocessor controlled ballast.
There are various problems relating to microprocessor controlled ballasts as such electronic ballasts in public lighting systems are becoming more complex and require greater amounts of equipment to be mounted therewith. Typical examples of such a ballast are described and claimed in European Patent Specification No. 1042942 (Noontek Limited) and European Patent Specification No. 1181845 (Noontek Limited). The ancillary equipment, in addition to the electronic ballast, can incorporate communication nodes, for example, GPS systems, diagnostic equipment and other devices needed for control and operation of such public lighting. However, with the increased power being handled by these microprocessor control ballasts and indeed the general complexity of equipment, the equipment is, of necessity, getting bigger. This poses various problems, not alone the problem of trying to fit the ballast and ancillary equipment within the luminaire, but also the need to dissipate the heat generated. Thus, designers of public lighting systems have considerable problems related to the compatibility of the electronic ballast, luminaires and columns. Ideally, for the designer, they would like to be able to choose whatever luminaire they required and that choice of luminaire should not, in any way, be effected by ballast issues. Similarly, it should be possible for the designers of the public lighting system to be able to design their ballasts and ancillary equipment, without the need to consider the design of luminaire in any great detail.
Obviously, if the ballast design and the design of the ancillary equipment can be effectively made independent of the luminaire design, there are great advantages for both sets of designers. For example, with the ballast, they will include, very often, reduction in costs, the ability to use more efficient ballasts and the ability to use whatever ancillary equipment is required. Further, there will be no need to constantly redesign the ballast for each new construction of luminaire.
The present invention is directed towards overcoming the problems inherent in the present constructions of public lighting systems incorporating microprocessor controlled ballasts.

Statements of Invention

According to the invention, there is provided a street lamp assembly comprising:

a hollow lamp column;
a luminaire having a lamp fitting therein for reception of a gas discharge lamp mounted on the lamp column; and
a microprocessor controlled ballast;
characterised in that substantially all of the microprocessor controlled ballast is mounted in the column adjacent the luminaire.

The advantage of this is that the design and construction of the ballast is essentially independent of the design and construction of the luminaire. Further, it removes effectively all constraints on the size of the ballast.
Further, the invention provides a lamp assembly in which all of the ballast is mounted in the column. This means that natural airflow through the column will provide cooling of the ballast.
In another embodiment of the invention, additional ancillary equipment is mounted in the column. The advantage of this is that any communications system, control equipment and the like, may be placed in the column and does not effect the design of the luminaire. Further, by placing the ballast at the top of the column, there is a considerable element of safety and will avoid vandalism related problems.
In another embodiment of the invention, by having the ballast in the column, it is possible to add as much equipment as is required.
In another embodiment of the invention, the ballast and ancillary equipment are mounted within a sealed tubular casing. This means that the whole ballast and all the ancillary equipment can be manufactured and assembled so as to be readily easily placed within the column, without any possibility of being damaged. Equally, it is easily removed and replaced.
In one embodiment of the invention, the tubular casing mounts an expandable mounting ring on a proximal end for securing within the column adjacent its upper end and a sealing ring at its distal end. This is a very neat way of mounting the tube within the column and preventing damage by vibration during use.
Ideally, the tubular casing is of a relatively high heat conducting material. This, together with the fact that there is a natural airflow through the column, will ensure that the heat is dissipated further. By this method of heat dissipation, the ballast and ancillary equipment will be kept dry and in a suitable working environment.
In another embodiment of the invention, the tubular casing is so configured and mounted as to allow the free passage of air through the hollow lamp column past the casing. This provides a suitable airflow through the column.
In a still further embodiment of the invention, the ballast and ancillary equipment are arranged longitudinally spaced apart on the one printed circuit board (PCB). There are now considerable design possibilities for the ballast.
Ideally, the PCB is mounted in a sealed tubular casing by heat conducting fasteners. This further permits heat dissipation.
It should be appreciated that this placing of the microprocessor controlled ballast and ancillary equipment remote from the luminaire, liberates both the luminaire designer and the ballast and ancillary equipment designer from any constraints imposed by the size and design of the luminaire. Effectively, the housing requirements for the electronic ballast and its ancillary equipment are removed. Effectively, one can now have much smaller luminaires, especially for higher wattages and this has considerable savings in that the columns can be less expensive, having to support a much reduced wind drag load. Similarly, the liberation of the need to provide the minimum bulk of ancillary equipment will have considerable advantages for authorities operating such public lighting systems in that a multiplicity of monitoring and control equipment may be mounted in the column, together with other services such as, for example, wireless internet access or Wi-Fi communications. Further, by this independence of ballast issues from luminaire issues, the design of both is now effectively unrestricted. Indeed, by allowing these, there will be considerable benefits from accuracy and time savings and indeed, it would be possible to easily scale up networks. Further, as mentioned above, there are safety advantages in placing the ballast at the top of the column and avoid vandalism related problems, in the sense that when a luminaire is damaged, it will not also damage the microprocessor or ballast. It also ensures there are no power problems in relation to the use of such microprocessor controlled ballasts.

Detailed Description of the Invention

The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 is a sectional, part diagrammatic view of a street lamp assembly according to the invention,
Fig. 2 is a side view of a microprocessor controlled ballast mounted in the street lamp assembly,
Fig. 3 is a plan view of the microprocessor controlled ballast,
Fig. 4 is a right-hand end view of the microprocessor controlled ballast,
Fig. 5 is a left-hand end view of the microprocessor controlled ballast,
Fig. 6 is a view similar to Fig. 1 of an alternative construction of street lamp assembly,
Fig. 7 is a view similar to Figs. 1 and 6 of a still further street lamp assembly according to the invention, and
Fig. 8 is an exploded diagrammatic view of a microprocessor controlled ballast fitted to the street lamp assembly of Fig. 8.

Referring to the drawings and initially to Figs. 1 to 5 thereof, there is provided a street lamp assembly, indicated generally by the reference numeral 1, comprising a hollow lamp column 2 mounting a luminaire 3 containing a gas discharge lamp 4. In the lamp column 2 is mounted a microprocessor controlled ballast 5 and ancillary equipment 6.
The luminaire 3 is mounted on the column 2 by fixing screws 7. Mains supply wires 8 are illustrated, as are wires 9 to the gas discharge lamp 4. The microprocessor control ballast 5 and the ancillary equipment 6 are mounted on a base plate 10. The base plate 10 is connected to an end cap 11 by a bracket 12 and fixing screws 13. The end cap 11 is mounted over the column 2. On the base plate 10 at the distal end thereof, there are mounted springs 15 for engagement with the column 2. The end cap 11 mounts vent holes 14.
In use, it will be noted that since the microprocessor controlled ballast 5 and the ancillary equipment 6 are remote from the luminaire 3, it is possible to use any ancillary equipment that is desired. A further advantage of this construction is that each of the pieces of ancillary equipment can be mounted separately and do not all have to be amalgamated together to take up the least space possible. Thus, there is a saving in costs in that space is not a consideration.
Referring now to Fig. 6, parts similar to those described with reference to the previous drawings, are identified by the same reference numerals. In this embodiment, the ballast 5 and ancillary equipment 6 are mounted within a tubular casing 20 to provide the one sub-assembly which is secured at its distal end 21 by a flexible board washer 22 and at its proximal end, by a bored end cap 23. The advantage now is that there is a total removable sub-assembly that can be used as desired.
Referring to Fig. 7, there is shown a still further embodiment, substantially similar to the embodiment of Fig. 7, and parts similar to those described with reference to Fig. 6 are identified by the same reference numerals. In this embodiment, however, instead of an end cap 23, the proximal end of the tubular casing 20 is mounted by means of an expandable cap 25 which can be seen in more detail in Fig. 8. Ideally, the tubular casing 20 is of a relatively high heat conducting material.
In this embodiment, the ballast 5 and ancillary equipment 6 are at mounted on the one PCB 27 which facilitates the manufacturing rules.
Ideally, the PCB 27 is mounted within the tubular casing 20 by heat conducting fasteners 28.
In the specification the terms "comprise, comprises, comprised and comprising" or any variation thereof and the terms "include, includes, included and including" or any variation thereof are considered to be totally interchangeable and they should all be afforded the widest possible interpretation and vice versa.
The invention is not limited to the embodiment hereinbefore described, but may be varied in both construction and detail within the scope of the claims.

Claims

A street lamp assembly (1) comprising:
a hollow lamp column (2);

a luminaire (3), having a lamp fitting therein for reception of a gas discharge lamp (4), mounted on the lamp column (2); and

a microprocessor controlled ballast (5);
characterised in that substantially all of the microprocessor controlled ballast (5) is mounted in the column (2) adjacent the luminaire (3).
A street lamp assembly (1) as claimed in claim 1, in which all of the ballast (5) is mounted in the column (2).
A street lamp assembly (1) as claimed in claim 1 or 2, in which additional ancillary equipment (6) is mounted in the column (2).
A street lamp assembly (1) as claimed in claim 3, in which the ancillary equipment (6) comprises communication nodes.
A street lamp assembly (1) as claimed in claim 3 or 4, in which the ballast (5) -and ancillary equipment (6) are mounted within a sealed tubular casing (20).
A street lamp assembly (1) as claimed in claim 5, in which the tubular casing (20) mounts an expandable mounting ring (25) on a proximal end for securing within the column (2) adjacent its upper end and a sealing ring (22) at its distal end.
A street lamp assembly (1) as claimed in claim 5 or 6, in which the tubular casing (20) is of a relatively high heat conducting material.
A street lamp assembly (1) as claimed in claim 6 or 7, in which the tubular casing (20) is so configured and mounted as to allow the free passage of air through the hollow lamp column (2) past the casing (20).
A street lamp assembly (1) as claimed in claim 3 and any preceding claim, in which the ballast (5) and ancillary equipment (6) are arranged longitudinally spaced apart on the one printed circuit board (PCB) (27).
A street lamp assembly (1) as claimed in claim 9, in which the PCB (27) is mounted in a sealed tubular casing (20) by heat conducting fasteners (28).