GB2255241A

GB2255241A - Power distribution device.

Info

Publication number: GB2255241A
Application number: GB9209070A
Authority: GB
Inventors: Andrew Black
Original assignee: FURNITURE DESIGN SERVICES LIMI
Current assignee: FURNITURE DESIGN SERVICES LIMI
Priority date: 1991-04-25
Filing date: 1992-04-27
Publication date: 1992-10-28
Also published as: GB9209070D0

Abstract

The device comprises a housing (6) which houses a number of power distribution sockets (2) which are individually switched, and are connected in parallel to a power supply via a residual current device (9), and on/off switch 11. The device may include telephone or computer sockets, or pneumatic, gas or vacuum sockets. The housing may bridge columns 41 of a workstation (fig. 8). <IMAGE>

Description

"Power Distribution Device" --This invention relates to power distribution~devices and especially, but not exclusively, devices for incorporation into furniture, such as work centres for office and industrial environments.

Conventional work centres which are incorporated into assembly lines for products generally comprise an upright frame on which is located a work top on which the product is assembled or partially assembled. A power distribution rail is normally located between two upright members of the frame above the work top.

The conventional power distribution rails have generally been supplied with a conventional 13 amp flex and plug so that they can be connected to a conventional 240 V, 50 Hz AC power supply. Previously power rails of this type have comprised a number of sockets to which electrical apparatus and devices can be connected and all the sockets have been switched by a single main switch in series between the power supply and the sockets.

Hence, the number of sockets which can be connected in this manner is limited by safety standards because they all operate off a single switch.

In addition, as the work environments are usually hazardous it is desirable to have some form of circuit breaking mechanism incorporated into the power supply.

This requires an additional device in the form of a circuit breaker to be located on the work centre, which of course requires a modification to the standard work centre and power rail.

According one aspect of the present invention, a power distribution device comprises, a housing, -a-n~electrical conductor for connection to a power supply, a number of power distribution sockets mounted on the housing and connected in parallel to the electrical conductor, and a residual current operated circuit breaker connected in series between the sockets and the electrical conductor and at least one switch mounted on the housing and connected between the electrical conductor and the power distribution sockets to control the power supply to the sockets.

In accordance with a second aspect of the present invention, a power distribution device comprises a housing, a number of power distribution sockets mounted on the housing, and a number of switches, each power distribution socket having one of the switches associated therewith, wherein a power distribution device comprising a housing, a number of power distribution sockets mounted on the housing, and a number of switches, each power distribution socket having one of the switches associated therewith, wherein the sockets are connected in parallel via their respective switches to an electrical conductor for connection to an external power supply, whereby the power supply to each socket is controlled by its associated switch.

Preferably, the first and second aspects of the invention are combined so that each socket has a switch associated with it and a circuit breaker is located in the housing between the sockets and the electrical conductors.

The advantage of this is that each socket is individually switched so that a relatively large number of sockets can be provided on one power distribution device without contravening safety regulations. The presence of a circuit breaker within the device has the advantage of not requiring specialist installation of the circuit breaker.

Typically, the circuit breaker could be a MK model LN 6730.

Typically, the device is for incorporation into an item of furniture and preferably, for incorporation into office or industrial furniture, such as a work centre used to assemble a product.

Preferably, the device further comprises a data/services compartment located within the housing and in which telephone and/or LAN sockets may be located.

Alternatively, or in addition, the data/services compartment could provide housing for other service sockets, such as pneumatics, chargers, nitrogen and other gas supplies, or for providing a vacuum.

Typically, the housing is fabricated from mild steel, zintec or any other suitable material which provides sufficient rigidity for the housing.

Two examples of a power distribution device in accordance with the invention will now be described with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of a first example of a power rail; Fig. 2 is a cross-sectional side view through the power rail shown in Fig. 1; Fig. 3 is a plan view of the power rail as shown in Fig. l with the power distribution sockets and~lid removed; Fig. 4 is a perspective view of a second example of a power rail; Fig. 5 is a cross-sectional side view of the power rail shown in Fig. 4; FIg. 6 is a plan view of the power rail shown in Fig. 4 with the lid and sockets removed; Fig. 7 is a circuit diagram for the power rails shown in Figs. 1 to 6; and, Fig. 8 is a schematic view of a work centre incorporating the power rail shown in Figs. 4 to 6.

Fig. 1 shows a power rail 1 which comprises two 13 amp, 3 pin sockets 2a, 2b and which each have a switch 3a, 3b and a light emitting diode (LED) 4a, 4b to indicate when the sockets are live.

The power rail 1 comprises a main housing 5 and two covers 6, 7 and the covers 6, 7 are attached to the housing 5 by means of screws 8. The cover 6 has an aperture through which a circuit breaker 9 protrudes and the circuit breaker 9 has a test button 10 and a circuit breaking switch 11. The cover 7 serves as a mounting for the sockets 2a, 2b which are attached to the cover 7 by means of screws 12.

The housing 5 has a flange 13 at each end with apertures 14 therein. The flanges 13 and apertures 14 enable the power rail 1 to be mounted in a suitable location, such as on a wall or other support by passing screws (not shown) through the apertures 14 and fixing the screws into the wall or support. Apertures 15 in the side walls of the housing 5 are also provided to enable power supply wires to be connected to a connector 16 mounted in the housing 5. The connector 16 is in turn connected to the circuit breaker 9, the sockets 2a, 2b and to earthing connections on the housing 5 and cover 6, 7.

As shown in Fig. 2 the circuit breaker is mounted in the housing 5 by means of the mounting plate 17.

Earthing points 18a, 18b are also shown for electrically earthing the housing 5. There are similar earthing points located on the under-sides of the cover 6, 7 but which are not shown for clarity. A plan view of the power rail 1 is shown in Fig. 3 with the covers 6, 7 removed. This view shows threaded sockets 19 on the housing 5 into which the screws 8 locate in order to secure the covers 6, 7 to the housing 5.

Figs. 4 to 6 show a second example of a power rail 20 which is similar to the power rail 1 shown in Figs 1 to 3 and similar components have identical reference numerals.

The main difference between the power rail 1 and the power rail 20 is that the power rail 20 has 8 sockets 2a to 2h which are individually switched by means of switches 3a to 3h. The sockets 2a to 2h are mounted on a cover 25 which is attached to a housing 26 of the power rail 20 by means of screws 8. In addition, the power rail 20 has an additional compartment 22 for the provision of data and telecommunication sockets and other services and supplies, such as pneumatics, electrical chargers, nitrogen and other gas supplies, and the provision of vacuum. The compartment 22 is also provided with an earthing point 18c and has a blanking cover 23 which may be fixed to the housing 26 prior to installation of the services and/or data communications sockets required by a user.An aperture 24 is provided in the side wall of the housing 26 for provision of electrical cables and/or power supplies to the compartment 23.

Fig. 7 is a schematic wiring diagram for the power rail shown in Figs. 1 to 6. The main power supply lines 30 enter the power rails 1, 20 through one of the apertures 15 and are connected to the connector block 16. From the connector block 16 the live wire 31 and the neutral wire 32 are connected to the circuit breaker 9. The circuit breaker 9 is typically a residual current-operated circuit breaker, such as a model LN6730 as supplied by NK. When a residual current is detected by the circuit breaker 9 the switch 11 is tripped with disconnects the output live and neutral wires 33, 34 from the input wires 31, 32. The circuit breaker 9 also has a test button 10 which when pressed opens the switch 11 if the circuit breaker 9 is functioning correctly.

The output live and neutral wires 33, 34 from the circuit breaker 9 are connected in parallel to the sockets 2a to 2x, where x designates the letter "b" for power rail 1 and the letter "h" for the power rail 20.

The neutral line 34 is connected directly to the neutral contact 35 of the sockets 2a to 2x and the live wire 33 is connected to switches 3a to 3x which are in turn connected to a live contact 36.

An earth wire 37 from the connector 16 is connected to the earthing points 18 on the power rails 1, 20 and is also connected to each of the sockets 2a to 2x at an earthing contact 38 on each socket.

As shown in Figs. 4 to 6 the power rail 20 has threaded mounting sockets 27 in each end and these are used to mount the power rail 20 on a work centre 40, as shown in Fig. 8. As shown in Fig. 8 the work centre 40 comprises two uprights 41 which are mounted on feet 42.

The uprights 41 support a lower cross member 43 which provides rigidity for the work centre, a work top 44, a shelf 45 and the power rail 20. Such a work centre may be used in assembly lines for assembling products, such as electrical products which may be for example computers and other electronic goods.

The advantage of the power rail 20 over conventional power rails is that it incorporates its own circuit breaker 9 and so it is not necessary to modify the work centre to add in a circuit breaker and each of the sockets 2a to 2x are individually switched which increases the safety of the power rail.

Modifications and improvements may be incorporated without departing from the scope of the invention.

Claims

1. A power distribution device comprising a housing, an electrical conductor for connection to a power supply, a number of power distribution sockets mounted on the housing and connected in parallel to the electrical conductor, a residual current operated circuit breaker connected in series between the sockets and the electrical conductor, and at least one switch mounted on the housing and connected between the electrical conductor and the power distribution sockets to control the power supply to the sockets.

2. A device according to Claim 1 wherein each power distribution socket has one switch associated therewith and the power supply to each socket is controlled by its associated switch.

3. A power distribution device comprising a housing, a number of power distribution sockets mounted on the housing, and a number of switches, each power distribution socket having one of the switches associated therewith, wherein the sockets are connected in parallel via their respective switches to an electrical conductor for connection to an external power supply, whereby the power supply to each socket is controlled by its associated switch.

4. A device according to any preceding claim, including a data compartment within the housing.

5. A device according to Claim 4, in which the data compartment provides housing for telephone and/or computer sockets.

6. A device according to any preceding claim, including a services compartment within the housing.

7. A device according to Claim 6, which the service compartment provides housing for one or more of: pneumatic service sockets, gas supply sockets, and vacuum sockets.

8. A device according to any preceding claim, in which the housing is fabricated from a rigid self-supporting material.

9. A device according to any preceding claim, in which the housing is adapted to be incorporated in an article of furniture.

10. An article of furniture comprising a pair of spaced apart columns and a device in accordance with any preceding claim mounted to span between the columns, the housing being provided at each end with means for securement to the columns.

11. A power distribution device substantially as herein described with reference to and as shown in Figs. 1 to 3 and 7 or Figs. 4 to 6 and 7 of the drawings.

12. An article of furniture substantially as herein described with reference to and as shown in Fig. 8 of the drawings.