| 摘要 |
298,577. Akt.-Ges. Brown, Boveri, et Cie. Oct. 11, 1927, [Convention date]. Void [Published under Sect. 91 of the Acts]. Tell-tale apparatus.-Relates to a system wherein the indications of a plurality of measuring instruments are repeated by a corresponding number of receivers over a smaller number of line wires in such a manner that continuous indications may be obtained. As shown, transmitters 2, which generate currents of frequencies proportional to the indications of the corresponding measuring instruments, are connected in a network which is connected by line wires Ll - - L<5> to a similar network of frequency responsive receivers 3. A direct current relay 1, such as a glow lamp, is connected in each arm of the transmitting and receiving networks. A battery b<1>, the voltage of which causes breakdown of a relay 1, is associated with the transmitting network in such a manner that with one pole of the battery connected temporarily with one corner of the network, the other pole is connected in turn to the other corners after which the first pole is connected to the next corner and the cycle is repeated. In this manner the relays 1 at the transmitter station G and the corresponding relays at the receiving station E function to connect periodically together corresponding transmitters and receivers. The circuit through one arm only of the transmitting network is completed at a time since the other circuits across the battery terminals contain at least two relays. The speed with which the battery terminals are associated with the transmitting network is such that the periodic signalling currents maintain continuous indications on all the receivers corresponding to the indications of the measuring instruments at the transmitting station. The receivers are of the measuring instrument type having no resetting force and each instrument may employ a source of light, the light being switched off automatically on the cessation of signalling impulses. The maximum voltage of each alternating current transmitter is made less than one half of the breakdown voltage of the relays 1 in order to ensure that operation does not take place when the signalling voltages in neighbouring arms of the network are in phase opposition. Moreover the voltage of the battery b<1> is greater than the breakdown voltage of the glow lamps by an amount equal to the maximum value of the alternating current used for signalling. Choking coils or resistances are connected in the battery circuit to prevent passage of signalling currents. The Specification as open to inspection under Sect. 91 (3) (a) states also that the indications of the receivers may be maintained by periodicallyoperated arresting devices and that the receivers may be of the crossed-coil " type of measuring instrument. This subject matter does not appear in the Specification as accepted. |
