Patent GB-190701596-A (GB)
Title: Improvements in and connected with Electrically Operated Switches specially applicable to Railway and other Vehicles.
Inventor: PARK CHARLES ARCHIBALD
Filed: 1907-01-21
Granted: 1908-03-21
Abstract: 1596. Park, C. A., and Mason, C. L. Jan. 21. Switches.-An electro-magnetic switch consists of two solenoids a, b, Fig. 1, the cores e, d of which, when raised, are retained by detents g, h. When either core is raised, an arm m fitted thereto knocks out the detent by which the other core is retained, thus allowing it to fall. If both cores are raised and simultaneously released, both fall before the detents come into action. An application of this apparatus is described in connexion with the lighting of railway trains and the like, in which the lights are primarily controlled by the guard, while switches are also fitted to each carriage. A dining or other special car may have a special switch which, except in one position, renders its lights independent of the guard's control. The above electro-magnetic device is so arranged, in connexion with brush switches 1, 2, 3, 4 and a three-line distributing-system for the control current, that energizing the coil a gives full lights, the coil b half lights, and both coils together, followed by. release, no lights. As regards the lighting system, Specifications No. 9882, A.D. 1899, and No. 23,187, A.D. 1905, [Abridgment Class Mechanism &c.], are referred to. The cores c, d may be moved either by the solenoids a, b, or by a hand-gear r which operates by a cam u through pivoted arms v. The cam u, when moved over to the right, raises the core d, which is retained by its detent but is preferably so shaped that, when subsequently moved over to the left and then released to allow a spring to return it to the central position, both cores miss their detents and fall. A further movement to the left raises the core c and allows it to be retained. The core c carries an arm 8 which is adapted to close switches 1, 2, and an arm 7 which opens a switch 3, when the core is raised. The core d has a projection which closes the switch 3, and another projection which opens the switch 4. In the latter position, the lamps 39, Fig. 13, are thrown in between the mains 34, 35, being fed directly from one battery 50, and from the other 49 through a resistance 42. In the former case, both sets of lamps light up, being supplied directly from a battery 50, and from a battery 49 through resistances 42, 46 in parallel. The guard's control switch is furnished with a series of contacts 14, 15, 16, 18, 19, 20, 21, Fig. 12, which can be bridged across in three series by a key-switch lever. Connexion across 15, 19 puts the solenoids b into circuit for half lights; connexion across 16, 20 energizes the solenoids a for full lights ; and connexion across 14, 18, 21 puts in both solenoids, subsequent release extinguishing all lights. The switch in the special car has, in addition to the above contacts, two springs 26, 27, which are connected to the distribution leads 30, 32, to the solenoids throughout the train, and which may make contact with pieces 28, 29, as shown. These springs are so shaped that, when the lever is over the contacts 15 or 10, the spring. 27 alone touches its contact-piece. In these positions, the lights can only be changed by the guard from half to full, but not vice versa. When the lever is placed over the contacts 14, 18, 21, both springs 26, 27 touch their contacts, and the lights are then completely under the guard's control. In a modification of this switch, the springs are so arranged that neither touches its contact except when the arm is in the last named position. In other positions, the lights in the car are independent of the guard's control.