GB190511336A - Improved Means for Supporting and Enclosing Telephone and other Electrical Apparatus - Google Patents

Abstract

11,336. Kingsbury, J. E., [Western Electric Co.]. May 30. Switches; cut-outs; distributing.-Relates to boxes for enclosing 0 telephone sets or other electric appliances, more particularly those employed in connexion with lines associated with power transmission circuits and consequently liable to high-potential crosses. The telephone apparatus is so arranged that when the door of the case is shut it is disconnected from the lines, and while the door is being opened it is connected to the lines through fuses, a lightning-arrester being also provided. The telephone apparatus, moreover, is separated from the chamber containing the fuses by an earthed metal plate by way of further protection. Fig. 6 shows the case with the door open. The telephone apparatus and the protective devices are mounted on a shelf b which slides in guideways b<1>, and when drawn forward can either be lifted out and detached, or dropped into an inclined position for examination of the apparatus. The line-wires are brought in at the back of the case and are connected to pairs of switch springs with which lugs forming one pair of terminals of the fuses engage when the shelf b is pushed back into its normal position in the case. The fuses h, h' are carried by spring holders i<1>, i<3> and a pair of lightning-arresters with a central earthed plate is arranged between them. These protective devices are separated by the metal plate b<3>, which supports them, from the right-hand compartment which contains the magneto, while the shelf b separates them from the telephone instruments, the shelf being earthed as stated. above. The door a<1> carries two bosses r<3>, g, which, when the door is closed, depress spring-controlled switch plungers f, r. The plunger f serves to open the switch e, e<1>, d, d', Fig. 9, thus disconnecting from the line L, and fuses h, h<1> the telephone apparatus and the lightning-arrester o, o'. The plunger r opens the switch q, ql in the microphone circuit to prevent waste of current. If abnormal pressures are present in the line, the fuses are blown when the door is being opened, thus protecting the operator from injury and notifying him of the condition of the apparatus. Fig. 7 is a vertical sectional view of the apparatus showing the fuses h, lightning-arrester o, o switch terminals n, n<1> of the line, and switch plunger f with the switch d, d', e, e' operated thereby.