GB191560A - Electric excess current cut-out - Google Patents

Abstract

191,560. M³ller, F. Nov. 21, 1921. No Patent granted (Sealing fee not paid). Automatic circuitbreakers to take the place of screw-plug fuses and made up in the same form, comprise a screw-plug casing with threaded plug contact c and central contact d and a spring-controlled rotary contact drum v carrying a radial contact p, Fig. 7, in engagement with a spring plate contact q. The circuit through the plug passes from the central contact d through an electromagnet f having poles r and through the contacts p, q to the plug contact c. When an excess current passes through the cut-out, the pole-pieces attract the catch t mounted on the spring arm s and remove it from locking engagement with the hook u on the contact drum v. Consequently the drum revolves in the direction of the arrow, withdrawing the radial contact from engagement with the spring contact. At the same time a screw-head 4 on the part y of the button engages a forked portion 2 of the spring contact and pushes it aside, as shown in Fig. 4. To re-set the cut-out, the guided spring-pressed button 1 is depressed to engage the pin x and rotate the drum into the locked position. The circuit is not made, however, until the pressbutton is allowed to return to release the extension 2 and allow the spring contact to engage the drum in the position shown in Fig. 1.