Patent GB-191107416-A (GB)
Title: Improvements in and relating to Time Switches for Electric Lighting.
Inventor: SCHRODER PAUL
IPC: H01H47/00
Filed: 1911-03-24
Granted: 1911-11-09
Abstract: 7416. Schr÷der, P. May 23, 1910, [Convention date]. Electro-magnetic switches.-Relates to electric lighting switches of the type that are closed electro-magnetically by means of a push-button switch and open automatically after a definite lighting interval, and consists in means for controlling and altering the action of such switches from the central station, whereby the switch may also be set to give continuous illumination or rendered completely inoperative. According to the position of a rotary switch b, which is set by means of impulses sent from the controlling station to a magnet R, different pairs of spring contacts d<1>, d<2>, d<3> are connected together. The setting - impulses are sent over the supply lines A, A'. If the supply is alternating, direct current from a battery B and choking-coils D, D' are employed. If the supply is direct, alternating current is employed in combination with condensers. As shown in the Figure, when the three contacts d<1>, d<2>, d<3> rest on an insulating-face of the rotary member, the lamp switch i is inoperative, as the local circuits for energizing its solenoid e cannot be completed by the consumer. In order to give continuous illumination, the controlling switch T at the central station is closed and opened once, whereupon the magnet R propels the next face of the rotary member under the contact springs and connects together the conductors c<1>, c<3>. The solenoid e is thus energized direct from the main A', closing the switch i which sends current to lamp L. The up-stroke of the core eventually opens an auxiliary switch l and cuts out the solenoid e, the switch i being held on by a lock s. The core is also locked in its raised position by a spring o, which is kept pressing on the escapement spring n of a retarding-train m by a pin q on the rotary member of the switch b, the last wheel of the retarding-train being in gear with the core of the solenoid e. This condition of the switches provides continual lighting. At the required time, the controlling- switch T is again opened and closed once, the rotary switch is propelled forward another step, the leads c<2>, c<3> are put into connexion, and the pin q ceases to lock the escapement. The solenoid core then falls, and the switch i is opened after a time-interval by the unlocking action of a pin g. Intermittent lighting can afterwards be obtained by the consumer by means of a push-switch K, the light being automatically cut off each time after the interval measured by the falling of the solenoid core. When no further lighting, continuous or intermittent, is required, the switch T is opened and closed a third time, and the contacts d<1>, d<2>, d<3> are brought on an insulating-face of the rotary member. The cycle of control is then ready to begin again. The switch at the controlling- station may be automatically operated. Instead of the escapement retarding - device, a heatswitch may be used, which is locked in its circuit - closed position for continuous illumination.