Patent GB-190427217-A (GB)
Title: A Device for Indicating the Names of Stations on Railway Lines, in the Passenger-Compartments of Railway Carriages.
Inventor: ESSER JOSEPH
Filed: 1904-12-14
Granted: 1905-08-03
Abstract: 27,217. Esser, J. May 2, [date applied for under Patents Act, A.D. 1901]. Indicators, station, stopping- place, and like. -Relates to means for indicating in the compartments of a train the name of the station at which the train is about to stop. The name is set up by the guard by the adjustment of letter-bearing discs, and simultaneous transmission to all the indicating- devices is then effected electrically. The transmitting- apparatus is shown in Figs. 1 and 2. On a shaft 1 are carried a number of drums 4 bearing the letters of the alphabet on their periphery. These discs are turned by the guard of the train to set up the name of the station. Secured to each disc is a scroll 2 provided with as many steps or teeth as there are characters on the drum 4. With each scroll is associated a pawl 5 pivoted at 7 and tensioned downwards by a spring 8. The pawl has a sector-shaped extension 6 bearing ratchet teeth 12. These teeth are engaged by a detent pawl 10 and a feed-pawl 11, carried respectively by the levers 13,14 and 15,16. In the process of composing the name of the station by means of the discs, the scrolls are turned into different positions relatively to the pawls 5, which at that time are at their greatest elevation. These adjustments having been made, the clockwork is wound up by the Key-pin 23, during which time, as explained below, the pawls 5 drop into contact with the scrolls. When the clockwork is set in motion, the feed-pawl 11 is reciprocated by an eccentric on the shaft 18, and it consequently feeds forward the ratchet 12 until it arrives at the last tooth, when the movement ceases. The oscillations thus produced in the detent pawl 11 cause a succession of contacts to be made between the tailend 14 of the pawl and the contact-springs 21. By this means a succession of currents is transmitted to the corresponding element of each receiving- apparatus, there being as many wires connecting the transmitter with the receivers as there are drums 4 in the transmitter. All the various current sequences, the number of impulses in each of which depends inversely on the height at which the pawl 5 was originally standing, are transmitted simultaneously. After about thirty rotations of the shaft 18, the clockwork is stopped by the action of a slot 27 on a pin 30, the pin 32 being thereby caused to enter a notch 34 in the disc 35. This lock is removed automatically when the clockwork is again wound up. During the winding of the clockwork, a notched disc on the shaft 41 operates levers that release both pawls 10, 11 from the ratchet 12 and thereby allow the pawls 5 to drop into contact with the scrolls 2. A second notched disc, shown in Fig. 5, on the shaft 41 causes a movement of a contact-arm 58 from the contact-spring 61 to the spring 63, thereby preventing the transmission of a current impulse due to the withdrawal of the pawl 10 from the ratchet 12. The receiving-apparatus is shown in Fig. 7. Each drum 4 in the transmitter is represented by a band 66 bearing letters and passing over a spring drum 64 and a feed-drum 65. The drums 65 are turned step by step by means of the electromagnets 72 and pawls 69. The drums 64 wind up the bands again when the detent pawls 74 are withdrawn by the electromagnet 78. This takes place while contact is made at 63, Fig. 5. Fig. 10 shows the circuits and connections employed. The contact made at 58, 63 during the winding up of the clockwork, as described above, causes the battery 81 to send current through the wires 83, 84 and electromagnet 78, thereby returning the letter-bearing bands at the receiving instruments to the normal position. When the contact 58, 61 is restored and the sector 6 lifted step by step, the successive contacts at 14, 21 close the circuit 85, 86, 87 through the electromagnet 72, and feed the band 66 forward until the desired character is displayed.