GB190108890A - Improvements relating to Printing Electric Telegraphs. - Google Patents

Abstract

8890. Heimerdinger, J. E. April 30. Drawings to Speciftcation. Telegraphs. -Relates to a system of printing- telegraphs in which the signal key for each character sends a predetermined combination of + and - weak and strong currents. At the receiving - station two selector relays operate numbers of series of selectable magnets by which the particular printing-magnet is selected, and on the closure of this circuit the printing is effected and the apparatus restored to its normal condition. At the transmitting-station, keys similar to typewriter keys are arranged so that their rear portions pass over series of contacts, and the front portions of the keys when depressed bear on a common contact-bar arranged in the local circuit. The rear contacts are connected to members of a series of four relays, the contacts of which are connected to battery and line, each relay being arranged to send a current of a peculiar character, such as a strong +, a weak -, &c. At the receiving-station, the signal currents pass to earth through two relays, one of which is polarized and the other only excited by strong currents. By this means the components of any signal are sorted out to the members of four electromagnet switches. The armatures of these switches are arranged by means of locking-devices and spring contacts to co-act with the armature of a second magnet, arranged in a shunt circuit so that the printing-circuit remains broken until the predetermined combination has been completed, when the local printing-circuit through one particular printing-magnet is closed. By the action of printing, the paper is fed and the local circuit is broken, so that the selecting-arrangements are returned to their normal positions. In a modified arrangement of the selecting-devices, the common shunt magnet is replaced by four magnets connected in series with the four selectable magnets and also arranged in circuit with the several battery contacts of the groups of spring contacts. The locking-devices and the spring contacts are also modified to suit this alteration.