GB202759A - Improvements in or relating to automatic telegraphy - Google Patents

Abstract

202,759. Heurtley, E. S., and Muirhead & Co., Ltd. June 1, 1922. Automatic telegraphs.-In an automatic transmitter employing perforated strip, the peckeroperated contact mechanism maintains contact made either for a positive or negative signalling impulse until a space or a marking contact of opposite polarity intervenes. The block signals may be broken up into beat signals, one for each time unit, by means driven in synchronism with the pecker-operated mechanism. The strip is fed in the usual manner by a motor driving a star wheel c<1> which engages the central perforations in the strip. Two peckers D (of which one only is shown) corresponding to the two rows of perforations of the strip are mounted on levers d pivoted at d<1> on the end of an arm of the rock ing-bar E rocked by means of a crank pin f on the shaft F. A large gear wheel G on the shaft C of the star-wheel c<1> gears with a small pinion f<1> on the shaft F so as to turn it one revolutior for each tenth of a revolution of the star-wheel c<1> which has ten teeth. The end d' of each lever ( is turned into the horizontal. Each contact lever H works between two contacts J and carries two arms K. The lever d is moved once for each step of the strip, and, according as the pecker I is or is not allowed to rise by' a perforation in th( tape, the end d<2> contacts with the lower or upper arm K to move the contact lever H against its corresponding contact where it is held, until posi tively moved, by a bias member h' and a spring h<2>. In a make and break mechanism to trans form these block signals into beat signals, a rock ing contact-lever L is pivoted on an adjustable support M, and its lower end meets a contact m<2>. The contact of the lever L is intermittently broken by means of a cam N on a shaft n, a pinion wheel n<1> on which is driven by the gear wheel G and makes one revolution for each step of the strip. The length of contact for each revolution may be adjusted by means of a pointer n<2> which is set against an indication on a scale O, and the support M of the lever L is adjusted until the lever just makes contact at m<2> wher the other end meets the cam. If both levers H are simultaneously on their marking contacts, the line is arranged to be earthed. If transmission is by means of relays, the marking contacts J, Fig. 1, of the two levers H are connected to opposite sides of two relay coils P, the armatures p of which move between contacts p<1>, one armature being earthed and the other connected to line, the upper and lower contacts being connected to opposite ends of a battery Q. If transmission is not effected by means of relays, the lever L is connected to line. and plays between two contacts one earthed and connected to an earthed contact lever H and the other connected to the second lever H. The marking and spacing contacts J are connected to opposite ends of a battery.