Improvements in or relating to remote control receivers for audio frequency central remote control installations superimposed on a network

摘要

845,946. Electric selective signalling systems. LANDIS & GYR A.G. April 29, 1958 [May 9, 1957], No. 13569/58. Class 40 (1). As described, in a broadcast control installation, the first five pulse positions g 1 to g 5 , Fig. 1, after a start pulse S 0 , are devoted to a call sign which selects a particular remote field station and prepares it for responding to the following two, 1 and 2, control signals. Subsequent control signals 3 and 4 &c. are effective, in the usual manner, at every field station. Each field station, Fig. 2, includes a call sign recognition device KZ, referred to in the Specification by the synonymous terms mechanical servo-lock and group auxiliary, which is driven by the main synchro. nous shaft a of the field station and has a lever U rocked by a solenoid G by each pulse received by the field station, and which, when it receives the call sign it is set to recognize, closes contacts KZ, thereby preparing the first two contacts 1 and 2 of the synchronous distributer W, for reception of the control signals 1 and 2. The call sign recognition device comprises a circular cam disc SC, Fig. 5, synchronously driven by the main driving-shaft a, Fig. 2, and having five positions each of which, in accordance with the call sign to be recognized is either protruded as at x, recessed as at y, or left at the normal level of the edge of the disc as at Z, a member ph pivoted on a shaft a 2 fixed to a lever U which is rocked by the solenoid G every time a pulse is received, and a contact controlling lever T pivoted on a fixed shaft a 3 . In operation, each pulse received rocks the further lever U, causing the member ph to rock about its arm h. If, when a pulse arrives, the arm h is in contact with the normal level of the edge of the disc SC, as at Z, then the end m of the member ph remains in contact with the bent end q of the lever T and the contacts KZ remain closed (as shown). If, however, a pulse arrives when the arm h is on a protrusion of the disc SC such as at x, then the member ph is moved sufficiently to allow the bent end q of the lever T to engage with a notch n 2 in the end of the member ph, thereby permitting a spring F to rotate the lever T about its fixed axis a 3 and causing the contacts KZ to open, and to remain open for the rest of the cycle. Similarly, if no pulse arrives when the arm h is in a recess in the disc SC, such as at y, then the contacts KZ are also opened with the bent end 1 of the member T locked in a notch n, as shown in Fig. 6. Thus, unless the pattern of pulses received during the first five pulse positions g 1 to g 5 , Fig. 1, corresponds with the way in which the cam disc SC has been shaped then contacts KZ are locked open for the remainder of the cycle. The code disc SC could be constructed with sliding portions appropriately positioned whereby protrusions or recesses can be synthesized at will on its periphery.