GB2186379A - Testing electric circuits and multi-point connectors - Google Patents

Abstract

A tester for testing electrical circuits running through a multiple-point plug and socket connection (not shown) is adapted to be interposed between the plug and the socket, and comprises a plurality of female connectors (14) adapted to be connected to the plug, a plurality of male connectors (15) adapted to be connected to the socket, and a plurality of display means (18) between respective connectors. Each display means is actuated when current flows between a corresponding female and male connector. The tester may be used to test lighting circuits for caravans or trailers. <IMAGE>

Description

SPECIFICATION Electrical circuit tester This invention relates two an electrical circuittesterfor testing electrical circuits running through a multiple-point plug and socket connection. The invention is particularly, but not exclusively, suitable for use in testing electrical circuits between a motor vehicle and a trailer or caravan.

A multiple-point plug and socket connection is now almost universally used to connect the electrical supply of motor vehicles to the appropriate equipment on a trailer or caravan, such as rear lights, brake lights, indicators and hazard warning lights. In a fitting which is now generally standardised, the plug comprises seven male electrical connectors, of which a central one is an earth connection, and the socket contains seven corresponding female electrical connectors. When the plug and socket are connected together, and the electrical circuits are functioning correctly, then operation of electrical equipment on the motor vehicle causes the corresponding equipment on the trailer or caravan also to function.For example, if the driver operates the righthand turn indicator, the corresponding indicator bulbs will function both on the motor vehicle itself and also on the trailer or caravan.

It isfound in practice that faults frequently develop in the electrical circuits described above. For example, if the driver operates the righthand turn indicator, the appropriate light bulbs may operate on the motor vehicle, but on the trailer or caravan either no light bulbs function orthe incorrect ones function.

When this happens, it can be a long and tedious process to iocate the fault. The plug has to be disconnected from the socket and a conventional circuit tester connected in turn between each respective pair of male and female connectors whilst operating the various electrical functions on the motor vehicle. It can therefore take a considerable time before the electrical fault is traced.

An object of the present invention is to provide a simple testing device which can enable electrical faults of the type described above to be rapidly detected.

The invention provides an electrical circu it tester for testing electrical circuits running through a multiple-point plug and socket connection, the tester being adapted to be electrically interposed between the plug and the socket, and comprising a plurality of female connectors adapted to be connected to the plug, a plurality of male connectors adapted to be connected to the socket, and a plurality of display means each electrically connected in series between each respective pair of female and male connectors such that each display means is actuated when currentflows between a corresponding female and male connector.

In a preferred embodiment, the display means are electrical light bulbs which become illuminated when current flows between a corresponding female and male connector.

Reference is now made to the accompanying drawing which is a diagrammatic side view, partly in section, of a preferred embodiment of electrical circuit tester according to the invention.

As shown in the drawing, the circu it tester comprises a housing 10 having two halves which mate together along a longitudinal division 11 and are held together by retaining screws 12 and 13. The housing is suitably made of clear plastics material which is transparent in the middle portion containing the light bulbs referred to below. The lefthand end portion of the circuit tester contains a plurality of female connectors 14which are adapted to engage electrically with the male connectors of a multiple-point plug. Similarly, the righthand end portion of the circu it tester contains a plurality of male connectors 15 which are adapted to engage electrically with the female connections of a multiple-point socket. Thus, the tester can be electrically interposed between the plug and socket.

Each female connector 14 is connected to a respective conducting strip 16 leading to an enclosure 17 containing an electrical light bulb 18.

Similarly, each male connector 15 is connected to a respective conducting strip 19 which in turn is connected to the respective enclosure 17. Each light bulb 18is maintained in electrical contactatits opposing ends with the respective conducting strips 16 and 19 by means of helical metal springs 20 and 21. Thus, each female connector 14 is in electrical series connection with a respective male connector 15 via a respective electrical light bulb 18. The light bulb is illuminated when current flows between the respectivefemaleand male connectors.

The detection of electrical faults in the circuits running from a motor vehicle to a trailer our caravan is very much simplified by the use of the circuit tester according to the invention. When such a fault develops, the ci rcuit tester is interposed between the plug and the socket. All that is necessary is then to operate the various electrical functions on the vehicle and observe the light bulbs on the tester. If one ofthe light bulbsfailsto illuminate, the circuit containing the fault is readily apparent.

1. An electrical circuit testerfortesting electrical circuits running through a multiple-pointplug and socket connection, the tester being adapted to be electrically interposed between the plug and the socket, and comprising a plurality offemale connectors adapted to be connected to the plug, a plurality of male connectors adapted to be connected to the socket, and a plurality of display means each electrically connected in series between each respective pair of female and male connectors such that each display means is actuated when currentflows between a corresponding female and male connector.

2. An electrical circu it tester according to Claim 1, in which the display means are electrical light bulbs which become illuminated when currentflows between a corresponding female and male connector.

3. An electrical ci rcuit tester substantially as hereinbefore described with reference to and as

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

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Electrical circuit tester This invention relates two an electrical circuittesterfor testing electrical circuits running through a multiple-point plug and socket connection. The invention is particularly, but not exclusively, suitable for use in testing electrical circuits between a motor vehicle and a trailer or caravan. A multiple-point plug and socket connection is now almost universally used to connect the electrical supply of motor vehicles to the appropriate equipment on a trailer or caravan, such as rear lights, brake lights, indicators and hazard warning lights. In a fitting which is now generally standardised, the plug comprises seven male electrical connectors, of which a central one is an earth connection, and the socket contains seven corresponding female electrical connectors. When the plug and socket are connected together, and the electrical circuits are functioning correctly, then operation of electrical equipment on the motor vehicle causes the corresponding equipment on the trailer or caravan also to function.For example, if the driver operates the righthand turn indicator, the corresponding indicator bulbs will function both on the motor vehicle itself and also on the trailer or caravan. It isfound in practice that faults frequently develop in the electrical circuits described above. For example, if the driver operates the righthand turn indicator, the appropriate light bulbs may operate on the motor vehicle, but on the trailer or caravan either no light bulbs function orthe incorrect ones function. When this happens, it can be a long and tedious process to iocate the fault. The plug has to be disconnected from the socket and a conventional circuit tester connected in turn between each respective pair of male and female connectors whilst operating the various electrical functions on the motor vehicle. It can therefore take a considerable time before the electrical fault is traced. An object of the present invention is to provide a simple testing device which can enable electrical faults of the type described above to be rapidly detected. The invention provides an electrical circu it tester for testing electrical circuits running through a multiple-point plug and socket connection, the tester being adapted to be electrically interposed between the plug and the socket, and comprising a plurality of female connectors adapted to be connected to the plug, a plurality of male connectors adapted to be connected to the socket, and a plurality of display means each electrically connected in series between each respective pair of female and male connectors such that each display means is actuated when currentflows between a corresponding female and male connector. In a preferred embodiment, the display means are electrical light bulbs which become illuminated when current flows between a corresponding female and male connector. Reference is now made to the accompanying drawing which is a diagrammatic side view, partly in section, of a preferred embodiment of electrical circuit tester according to the invention. As shown in the drawing, the circu it tester comprises a housing 10 having two halves which mate together along a longitudinal division 11 and are held together by retaining screws 12 and 13. The housing is suitably made of clear plastics material which is transparent in the middle portion containing the light bulbs referred to below. The lefthand end portion of the circuit tester contains a plurality of female connectors 14which are adapted to engage electrically with the male connectors of a multiple-point plug. Similarly, the righthand end portion of the circu it tester contains a plurality of male connectors 15 which are adapted to engage electrically with the female connections of a multiple-point socket. Thus, the tester can be electrically interposed between the plug and socket. Each female connector 14 is connected to a respective conducting strip 16 leading to an enclosure 17 containing an electrical light bulb 18. Similarly, each male connector 15 is connected to a respective conducting strip 19 which in turn is connected to the respective enclosure 17. Each light bulb 18is maintained in electrical contactatits opposing ends with the respective conducting strips 16 and 19 by means of helical metal springs 20 and 21. Thus, each female connector 14 is in electrical series connection with a respective male connector 15 via a respective electrical light bulb 18. The light bulb is illuminated when current flows between the respectivefemaleand male connectors. The detection of electrical faults in the circuits running from a motor vehicle to a trailer our caravan is very much simplified by the use of the circuit tester according to the invention. When such a fault develops, the ci rcuit tester is interposed between the plug and the socket. All that is necessary is then to operate the various electrical functions on the vehicle and observe the light bulbs on the tester. If one ofthe light bulbsfailsto illuminate, the circuit containing the fault is readily apparent. CLAIMS

1. An electrical circuit testerfortesting electrical circuits running through a multiple-pointplug and socket connection, the tester being adapted to be electrically interposed between the plug and the socket, and comprising a plurality offemale connectors adapted to be connected to the plug, a plurality of male connectors adapted to be connected to the socket, and a plurality of display means each electrically connected in series between each respective pair of female and male connectors such that each display means is actuated when currentflows between a corresponding female and male connector.

2. An electrical circu it tester according to Claim 1, in which the display means are electrical light bulbs which become illuminated when currentflows between a corresponding female and male connector.

3. An electrical ci rcuit tester substantially as hereinbefore described with reference to and as shown in the accompanying drawing.