GB2164810A

GB2164810A - Improvements in or relating to fluorescent lighting circuits and fittings

Info

Publication number: GB2164810A
Application number: GB08516349A
Authority: GB
Inventors: Peter Barker
Original assignee: RIC Ltd
Current assignee: RIC Ltd
Priority date: 1984-09-18
Filing date: 1985-06-28
Publication date: 1986-03-26
Also published as: GB8423611D0; GB8516349D0; GB2164810B

Abstract

A fluorescent lighting circuit employs a unit 10 composed of a housing 11 containing a capacitor C for connection with at least one ballast choke T and one or more electronic starter circuits K, the capacitor C and starter circuit K, or circuits (K1), (K2), (Figs. 4, 5) being electrically connected to terminals 1-4, (1-6), accessible externally of the housing 11. The housing 11 may be formed from plastics mouldings with the terminals on its end walls. <IMAGE>

Description

SPECIFICATION Improvements in or relating to fluorescent lighting circuits and fittings The present invention is concerned primarily with devices for use with fluorescent light circuits and fittings.

Conventional fluorescent light fittings employ a fluorescent tube, a choke ballast, a capacitor connected to the choke and a starter. The starter is usually a glow-starter with a glow discharge tube and bi-metallic switch. Electronic starter circuits have become available more recently. Hitherto the conventional fitting has the starter accessible for replacement from the exterior as is the tube itself, whereas the capacitor and choke are mounted within the fitting not in a readily accessible position.

In this way the tube and starter can be replaced from time to time when these fail.

A general object of the present invention is to provide an improved unit for use with fluorescent light fittings.

According to the present invention a unit for use with a fluorescent light fitting and lighting circuit arrangement thereof has a housing, conveniently elongate, containing a capacitor for series or parallel connection with a choke of the circuit arrangement and an electronic fluorescent tube starter circuit for connection across a fluorescent lamp or tube and individual terminals accessible externally of the housing connected electrically to said starter circuit and the capacitor contained in the housing. The unit would be electrically connected in use to the choke and to a fluorescent lamp or tube and would be mounted within the light fitting in a position not readily accessible.

The individual terminals can be at the ends of the housing of the unit and preferably use push-in type solderless connections for example of the type described in UK Patent Specification 1 406 487. The starter circuit can itself be embodied in a variety of forms.

The capacitor may be of metallised polypropylene type commonly employed in fluorescent lighting circuits. The combination of the capacitor and electronic starter circuit within a single housing reduces costs and assembly time.

The invention also provides a fluorescent lighting arrangement comprising a fluorescent lamp or tube, a choke connected to the lamp or tube and to a first mains supply terminal, an electronic starter circuit for initiating ionization and conduction through the lamp or tube connected across the ube, a second mains supply terminal connected to the lamp or tube and a capacitor connected across the first and second mains supply terminals or in series with the choke; wherein the capacitor and the starter circuit are disposed as separate entities within a common housing to form a compact unit and the housing has means accessible from its exterior for establishing separate electrical connection with the capacitor and the starter circuit.

The invention may be understood more readily, and various other features of the invention may become apparent, from consideration of the following description.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, wherein: Figure 1 is a perspective view of a unit constructed in accordance with the invention; Figures 2 and 3 are schematic circuit diagrams showing the unit of Fig. 1 in use; and Figures 4 and 5 depict an alternative circuit and unit.

Fig. 1 depicts a composite unit 10 composed of a cylindrical housing 11 with a main wall 18 and end walls 12. Each end wall 12 has a terminal block 13 provided with terminals permitting solderless connection with external electrical leads. Each terminal block 13 may have a number of terminals all or some of which are connected to the components inside the housing 11. The terminals of blocks 13 which are employed during use are designated 1 to 4 in Fig. 1 and in Figs. 2 and 3.

The end walls 12 with their blocks 13 and the main wall 18 may be synthetic plastics mouldings. Within the housing 11 there are two components represented in dotted outline, namely a capacitor C and an electronic starter circuit K electrically connected with the respective terminals 1, 2 and 3, 4 of the terminal blocks 13 and isolated from one another. The starter circuit K serves as a starter for a fluorescent lamp or tube while the capacitor C is connected with a choke operably associated with the tube. Fig. 2 shows the unit 10 in one type of circuit arrangement i.e.

combined with a choke T, a fluorescent tube F and mains terminals L and N. In this arrangement the capacitor C is connected across the terminals L and N in parallel with the choke T to provide power factor correction. The starter is connected across the tube F. Fig. 3 depicts another circuit arrangement with the capacitor C in series with the choke T.

Instead of actively employing four terminals 1-4, the unit 10 could employ six terminals 1-6 and be incorporated in a twin starter application such as is illustrated in Fig. 4. The single capacitor C is here in parallel with the two chokes T1, T2 but is could be in series therewith as shown in Fig. 3. Two starter circuits K1, K2 are contained in the unit 10, with the single capacitor C. Fig. 5 depicts the modified unit 10 of Fig. 4 with the six terminals 1 to 6 wherein the additional terminals 5 and 6 are provided by one of the terminals blocks 13.

Claims

1. A unit for use in a fluorescent lighting circuit arrangement; said unit being composed of a housing containing a capacitor for series of parallel connection with a choke of the circuit arrangement and an electronic fluorescent tube starter circuit for connection across a fluorescent lamp or tube and individual terminals accessible externally of the housing connected electrically to said starter circuit and said capacitor contained in said housing.

2. A unit according to claim 1, wherein the housing is elongate at least with a pair of terminals at each end.

3. A unit according to claim 1, wherein a further electronic fluorescent tube starter circuit is provided in the housing and further individual terminals accessible externally of the housing are connected electrically to and further starter circuit.

4. A unit according to claim 1 or 3, wherein the housing is elongate with terminals at both ends.

5. A unit substantially as described with reference to, and as illustrated in Fig. 1 or 5 of the accompanying drawings.

6. A fluorescent lighting circuit arrangement comprising a fluorescent lamp or tube, a choke connected to the tube and to a first mains supply terminal, an electronic starter circuit for initiating ionization and conduction through the lamp or tube connected across the lamp or tube, a second mains supply terminal connected to the lamp or tube and a capacitor connected across the first and second mains supply terminals or in series with the choke; wherein the capacitor and the starter circuit are disposed as separate entities within a common housing to form a compact unit and the housing has means accessible from its exterior for establishing separate electrical connection with the capacitor and the starter circuit as defined.

7. A circuit arrangement according to claim 6 and comprising a further fluorescent lamp or tube, a further choke connected to the further lamp or tube and to said first mains supply terminal and a further starter circuit for initiating ionization and conduction through the further lamp or tube, the further starter circuit being also disposed in the common housing, there being means accessible from the exterior of the housing for establishing separate electrical connection with the further starter circuit.

8. A fluorescent lighting circuit substantially as described with reference to, and as illustrated in, Fig. 2, 3 or 4 of the accompanying drawings.