GB2179208A - Device for interrupting flow of electricity - Google Patents

Abstract

A device for interrupting the flow of electricity to an electrical appliance comprising essentially a container in which a socket (7) receiving electricity from a mains supply is attached to the bottom of the container. A plug (10) receiving current from the socket is connected to the lid (4) of the container and the plug also transmits the supply to an appliance. When the lid is in position the plug and socket are united. However when the lid is removed the plug is withdrawn from the socket and interrupts the flow of the supply through the plug to the appliance. The device is of particular use in the construction of a safety light in which the appliance comprises an electric light forming part of a circuit incorporating a rechargeable battery so that when the mains supply of electricity through the socket to the plug fails the battery enables the light to continue to function. <IMAGE>

Description

SPECIFICATION Improved means for interrupting the supply of electric current to an appliance and to electric appliances incorporating the same This invention relates to a device for interrupting the supply of current to an electrical appliance including luminaires and more particularly to such appliances when used in conjuntion with such a device.

The installation of electrical appliances in public and domestic buildings is subject to extensive regulations. One of these stipulates that where a switch is mounted on an appliance including a luminaire is intended to serve as a means of switching off the appliance for mechanical maintenance, the connections shall be so arranged that the appliance can be dismantled to the extent necessary for mechanical maintenance without thereby exposing any parts which remain live when the switch is open. Furthermore any conductors or cables which remain live shall be as short as possible and separated from other live conductors or cables by screens or earthed metal or suitable barriers of insulating material.

Compliance with the various regulations can cause considerable expense and inconvenience. For example when the use of an isolating switch is entailed that is a switch which isolates the appliance from the mains supply of electricity to enable its repair or maintenance to be carried out. In such cases a switch may be used to isolate a number of appliances e.g. electric iights. Consequently when the switch is opened all the appliances will be put out of operation even though one only of the appliances may require maintenance. In other instances an operative may have to walk a considerable distance in order to isolate a particular appliance. The present invention is directed to a means for isolating an electrical appliance which is relatively inexpensive to manufacture and which is both safe and convenient to use.

Accordingly this invention provides a device for interrupting the supply of electricity to an electrical appliance comprising a container formed by uniting a first and second member, the first member bearing a terminal for receiving a supply of electricty from a mains supply and thesesbrfl member bearing a terminal for receiving the supply from the first terminal and for transmitting the same to the appliance or a part thereof locatable within the container the relative positionsof the two terminals being such so that when the container is closed the two terminals are united and the supply is capable of flowing to any appliance or part thereof located within the container and when the container is opened the terminals become separated and the flow of current to the appliance is interrupted.

This invention is illustrated but not restricted by the following drawings in which: Figure lisa side view taken in vertical section of invention device.

Figure 2 is a side view taken in vertical section of the device shown in Figure 1, in which the lid of the device shown as numerai (3) in Figure 1 is being removed.

Figure 3 shows a side view taken in vertical section of an emergency lighting system incorporating invention device.

In Figures 1 and 2 a container shown generally as numeral (1) made preferably of any waterproof nonconducting material for example a thermoplastics or thermosetting resin consists of a hollow portion (2) and a lid (3). The latter is maintained in position by a shoulder member (4) passing through a slit in the wall of the container (2). The lid is also provided with a press stud locking pin (5) which engages with a shoulder formed by a slit in the rim (6) of the hollow part of the container (2). The latter is provided with a socket (7) which is connected to a mains supply of electricity whilst a plug (8) is secured by bracket (9) to lid (3). Plug (8) is provided with terminals (10 and 11) for connection to a part or whole of an electrical appliance which can be housed within the container.Lid (3) can be removed by unlocking press sttid locking pin (5) raising and the lid whilst sliding the shoulder member (4) out of the slit in the wall of container (2). When the lid has been removed pins (12) are automatically withdrawn from socket (7) thus interrupting the supply to any appliance which may be connected to terminals (10 and 11).

Figure 3 illustrates an emergency lighting system incorporating the present device. Numerals 1 to 11 represent the same features as those described in Figures 1 and 2. Terminals (10 and 11) are connected to a lighting circuit (13) which incorporates a bulb and among other components (not shown) a rechargeable battery. Under normal conditions the bulb may be monitored against failure or illuminated by electricity supply from the mains through terminal (10 and 11). However if the mains supply should fail the battery in circuit (13) is wrought automatically into action so as to ensure that the bulb continues to provide light.In the event of the emergency light requiring maintenance the lid or geartray (3) can be removed in the manner described above in which case the whole of the system becomes separated completely from the mains supply at socket 112).

The present device can be modified in different ways. Thus the size of the container can be made to fit different quantities of circuitry which preferably is secured to the lid rather than the sides or bottom of the container.

Devices according to the present invention can be used as components for a wide variety of different appliances for example, fire alarm control panels, boiler controls, communication control equipment, charger control equipment, inverter control units, electric fans, electric heaters, security control panels, self contained security devices i.e. infra red light switch units, audible or visual warning units, and power eupply units.

1.An isolating device for interrupting the supply of electricity to an electrical appliance comprising a container formed by uniting a first member and a second member, the first member bearing a

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improved means for interrupting the supply of electric current to an appliance and to electric appliances incorporating the same This invention relates to a device for interrupting the supply of current to an electrical appliance including luminaires and more particularly to such appliances when used in conjuntion with such a device. The installation of electrical appliances in public and domestic buildings is subject to extensive regulations. One of these stipulates that where a switch is mounted on an appliance including a luminaire is intended to serve as a means of switching off the appliance for mechanical maintenance, the connections shall be so arranged that the appliance can be dismantled to the extent necessary for mechanical maintenance without thereby exposing any parts which remain live when the switch is open. Furthermore any conductors or cables which remain live shall be as short as possible and separated from other live conductors or cables by screens or earthed metal or suitable barriers of insulating material. Compliance with the various regulations can cause considerable expense and inconvenience. For example when the use of an isolating switch is entailed that is a switch which isolates the appliance from the mains supply of electricity to enable its repair or maintenance to be carried out. In such cases a switch may be used to isolate a number of appliances e.g. electric iights. Consequently when the switch is opened all the appliances will be put out of operation even though one only of the appliances may require maintenance. In other instances an operative may have to walk a considerable distance in order to isolate a particular appliance. The present invention is directed to a means for isolating an electrical appliance which is relatively inexpensive to manufacture and which is both safe and convenient to use. Accordingly this invention provides a device for interrupting the supply of electricity to an electrical appliance comprising a container formed by uniting a first and second member, the first member bearing a terminal for receiving a supply of electricty from a mains supply and thesesbrfl member bearing a terminal for receiving the supply from the first terminal and for transmitting the same to the appliance or a part thereof locatable within the container the relative positionsof the two terminals being such so that when the container is closed the two terminals are united and the supply is capable of flowing to any appliance or part thereof located within the container and when the container is opened the terminals become separated and the flow of current to the appliance is interrupted. This invention is illustrated but not restricted by the following drawings in which: Figure lisa side view taken in vertical section of invention device. Figure 2 is a side view taken in vertical section of the device shown in Figure 1, in which the lid of the device shown as numerai (3) in Figure 1 is being removed. Figure 3 shows a side view taken in vertical section of an emergency lighting system incorporating invention device. In Figures 1 and 2 a container shown generally as numeral (1) made preferably of any waterproof nonconducting material for example a thermoplastics or thermosetting resin consists of a hollow portion (2) and a lid (3). The latter is maintained in position by a shoulder member (4) passing through a slit in the wall of the container (2). The lid is also provided with a press stud locking pin (5) which engages with a shoulder formed by a slit in the rim (6) of the hollow part of the container (2). The latter is provided with a socket (7) which is connected to a mains supply of electricity whilst a plug (8) is secured by bracket (9) to lid (3). Plug (8) is provided with terminals (10 and 11) for connection to a part or whole of an electrical appliance which can be housed within the container.Lid (3) can be removed by unlocking press sttid locking pin (5) raising and the lid whilst sliding the shoulder member (4) out of the slit in the wall of container (2). When the lid has been removed pins (12) are automatically withdrawn from socket (7) thus interrupting the supply to any appliance which may be connected to terminals (10 and 11). Figure 3 illustrates an emergency lighting system incorporating the present device. Numerals 1 to 11 represent the same features as those described in Figures 1 and 2. Terminals (10 and 11) are connected to a lighting circuit (13) which incorporates a bulb and among other components (not shown) a rechargeable battery. Under normal conditions the bulb may be monitored against failure or illuminated by electricity supply from the mains through terminal (10 and 11). However if the mains supply should fail the battery in circuit (13) is wrought automatically into action so as to ensure that the bulb continues to provide light.In the event of the emergency light requiring maintenance the lid or geartray (3) can be removed in the manner described above in which case the whole of the system becomes separated completely from the mains supply at socket 112). The present device can be modified in different ways. Thus the size of the container can be made to fit different quantities of circuitry which preferably is secured to the lid rather than the sides or bottom of the container. Devices according to the present invention can be used as components for a wide variety of different appliances for example, fire alarm control panels, boiler controls, communication control equipment, charger control equipment, inverter control units, electric fans, electric heaters, security control panels, self contained security devices i.e. infra red light switch units, audible or visual warning units, and power eupply units. CLAIMS

1.An isolating device for interrupting the supply of electricity to an electrical appliance comprising a container formed by uniting a first member and a second member, the first member bearing a terminal for receiving a supply of electricity from a mains supply of electricity and the second member bearing a terminal for receiving the supply from the first terminal and for transmitting the same to the appliance the relative positions of the two terminals being such so that when the container is closed the two terminals are united and the supply of electricity flows to the appliance and when the container is opened the flow of electricity to the appliance is interrupted.

2. An isolating device according to Claim 1 wherein the first member is a socket which is secured to the base of the container and the second member is a plug which is secured to the lid of the container.

3. A device according to either of Claims 1 or 2 wherein the appliance is an electric light forming part of an electric circuit incorporating a battery for ensuring that the light continues to function in the event of the supply of electric current from the first member becoming interrupted.

4. Isolating devices as hereinbefore claimed in any one of the preceding claims.

5. Isolating devices as hereinbefore described with particular reference to the drawings.