Patent GB-190629584-A (GB)
Title: Improvements in and relating to Circuit Controlling Mechanism
Filed: 1906-12-28
Granted: 1907-12-28
Abstract: 29,584. British Thomson-Houston Co., [General Electric Co.]. Dec. 28. Distributing; cut - outs; switches.-A oircuitcontrolling. device comprises two automatic circuitbreakers one connected in each lead of the circuit to be controlled and having common operating-mechanism, so that, by means of a lostmotion connexion, either circuit-breaker may be closed, and the circuit may then be completed by closing the other circuit-breaker by an opposite motion of the operating-handle, which assumes a neutral position when released by the operator. In case an overload is produced when the circuit is closed, the first circuit-breaker is automatically tripped and the. circuit opened, so that it is impossible to keep the circuit closed so long as the overload. conditions persist. The common operating-means, shown in Fig. 4 in the position when the circuit breakers are open, consist of a rod 10 made in two. sections rigidly secured together through an insulating-plate 33, and having the operating-handle. 34 keyed on one end. A hub 35 is secured to the shaft, and carries an arm 36 on which is mounted a pin 37 near another fixed pin 38 carried by -the casing. A spiral spring 39 surrounds the hub, and its ends engage the pins 37, 38 on either side, so that, if the shaft is rotated in either direction and released, the spring compels the shaft to return to its neutral position. The bridging contacts 9 are carried by insutating-arms 9<a> mounted on loose hubs on the shaft. The hubs have heels 26, which, when the circuit is open, are pressed by spiral springs 24 into engagement with fixed rods 25 carried by the casing. A lost-motion connexion between the operating-shaft 10 and the hubs that carry the movable contacts consists of operating-sleeves 40, 41, rigidly secured to the shaft and provided with lug. adapted to engage shoulders 46, 47, 48 on the hubs. The movable contacts are adapted to bridge fixed contacts 7, 8, as shown in Figs. 1 and 7. The contacts 7 are connected with the, main leads 4, 5, and the contacts 8 are connected to one end of the windings of overload coils 16, the other ends of which are connected to terminals 17 to which the leads 18 of the branch circuit are secured. Arcing tips 11 are mounted above the contacts upon the walls 12 of an arc-shute. In operation, when the handle 34 is moved in either direction, one of the lugs on the sleeves 40, 41 engages one of the shoulders 46, 48 on the hubs carrying the Contacts 9, one of which is then moved into engagement with the fixed contacts 7, 8, where it is locked into position by a pivoted catch 22, Fig: 3, connected to the armature 19 of the overload coil 16. When the handle is moved in the opposite direction, the other contact 9 is similarly moved into engagement with the other pair of contacts 7, 8, where it is also locked in position. On an overload, the switches are tripped by the coils 16, which attract their armatures 19 and so. release the catches 22 the switch arms returning to their neutral position under the action of the springs 24. The switches may also be tripped by hand by pulling a knob 29 on a rod 28, which is provided with a shoulder 30 to engage an extension 19<a> on one of the armatures, and an adjustable sleeve31 to engage one end of a lever 27, the other end of which engages a similar extension 19<a> on the other armature.