摘要 |
A simple and inexpensive elongate pressure-actuated electrical switch especially suitable for security purposes comprises a flexible tubular body of insulating material having air within its bore and incorporating at opposed locations around its periphery two sectoral portions of electrically conductive material. Two elongate conductors extend lengthwise in electrical contact with the conductive sectoral portion and two electric conductors extend lengthwise in contact with the conductive sectoral portion. The sectoral portions have a conductivity less than that of the conductors. An overall outer sheath surrounds the tubular body and conductors and has a flat surface which is suitable for supporting the switch on the ground and which is so positioned with respect to the sectoral portions that one conductive sectoral portion is at a position intermediate of the flat surface and the other conductive sectoral portion. When downwardly directed pressure is applied to the sheath the opposed electrically conductive sectoral portions are pressed into contact with one another to effect electrical connection between the conductors. |