GB766961A - Improvements in or relating to telegraph transmitters - Google Patents

Abstract

766,961. Printing-telegraph transmitters. SIEMENS & HALSKE AKT.-GES. Feb. 9, 1955 [Feb. 9, 1954], No. 3929/55. Class 40 (3). In a telegraph transmitter in which levers selectively rocked by cams on a rotating shaft in dependence on the selective setting of corresponding selector elements temporarily displace from its normal position a common intermediate member provided with two surfaces operative to control the transmitting contact arrangement to a marking or spacing position by a control member actuated at predetermined times during the revolution of the rotating shaft, the operative surfaces of the intermediate member extend appreciably in the direction in which they are moved during the displacement of the intermediate member by the rocking of the said levers. A lever 3 is rocked clockwise when its projection 3a engages the low portion of its associated cam 2 and its end is not impeded by the upstanding portion of the associated selector bar 6 in its left-hand position. The movement of a lever 3 rocks the intermediate member 7 about a shaft 8 in a support 10 so that its projection 7b is in a position to be engaged by an extension 12b on a control member 12 arranged to be rocked by a star-shaped cam 15 immediately after a lever 3 has co-operated with the low portion of its associated cam 2. If the member 7 is not rocked, its projection 7a is in a position to be engaged by the extension 12a of the control member 12. The support 10 carrying the member 7 is secured to a shaft 11 on which is mounted a contact-operating member 16 having end surfaces comprising portions 16a, 16b of different curvatures connected by an inclined surface. The anticlockwise rotational movement of the member 16 by the member 7 closes contacts 17 and opens contacts 18. The shaft 11 carries a braking device comprising discs 20 held between spring-biased plates 21. For single-current working, one of the pairs of contacts 17, 18 may be dead. In a modification, Fig. 2 (not shown), spring-biased levers having separate extensions associated respectively with levers controlled by the selector bars and with the low portions of the cams operate a frame member with an arm engaging in the recess between the arms of a V- shaped intermediate member. The ends of the forked arms are associated with axial extensions of a contact-operating lever mounted on a shaft carrying a contact-operating arm which opens one or the other pair of two pairs of contacts. The V-shaped member is raised by a star-shaped cam immediately after a frame-operating lever has engaged the low portion of its associated cam.