GB367115A - Improvements in gas-blast electric switches - Google Patents

Abstract

367,115. Delivering measured quantities. RUPPEL, S., 8, Palmengartenstrasse, Frankfort-on-Main, Germany. Jan. 12, 1931, No. 985. Convention date, Jan. 16, 1930. [Class 106 (v).] A measured quantity of gas under pressure, e.g. carbonic acid gas, for quenching the arc is supplied to a high tension switch from a container for the liquefied gas by means of a measuring chamber with valve controlled inlet and outlet openings of large area to avoid throttling. The measuring chamber 10, Fig. 1, has inlet and outlet valves 7, 9 connected by a piston-rod 8 to a piston 4 working in a housing 1 connected to the carbonic acid bottle by a pipe 15. The piston 4 has passages 5 and when a relief valve 3 above the piston is closed the pressure of the liquid moves the valves into the position shown and the measuring chamber fills. On opening the relief valve 3 the piston 4 moves upwards closing the valve 7 and opening the outlet valve 9, the contents of the chamber 10 flowing to the switch through a passage 14. The capacity of the chamber 10 is varied by an adjustable piston 12. One or both of the valves may be formed as actuating pistons. The relief valve 3 may be controlled electrically or pneumatically. Fig. 5 shows a modification comprising a piston valve 41 connected with a disc valve 34 adapted to close the outlet opening 14. A valve 45 in the inlet pipe 15 is normally kept open by a spring 46, the liquid under pressure passing to the back of the piston valve 41 through a passage 44 and openings 43, 42 in the piston valve. On opening the relief valve 3 the pressure behind the piston valve drops and the valve moves to the right opening the outlet 14, valve 45 closes and the quantity of liquid above the valve 45 is discharged. Fig. 2 shows a rotary measuring cock 16 connected by a stem 18 with a valve member 17 ; in one position liquid entering at 27 fills the chamber 16 through passages 25, 26, 21. Turning the chamber to the position shown by a lever 29 allows the measured quantity to discharge through passages 20, 24, 19. Passages 22, 23 connect the spaces above and below the valve 17 with the space above the measuring chamber and any leakage escapes through a whistle 32 giving an audible warning. Alternatively leakage may open or close a contact of an alarm circuit. The inlet and outlet piston valves may operate in separate cylinders each with a relief valve. Additional flow of gas to the switch &c. may be provided for by opening both valves simultaneously. In order to prevent freezing the measuring chamber may be provided with heating means or the passages may have means for increasing the velocity of flow such as perforated screens or baffles. The piston valves may be so formed that the loss of gas through the relief valves 3 is minimized.