Improved Apparatus for Maintaining Proportional Delivery of Gas and Air to Gas-fired Furnaces.

摘要

120,076. Keith, J., and Keith, G. Oct. 20. 1917. Fluid-actuated valves.- Apparatus for maintaining proportional delivery of gas and air to a furnace consists of two connected diaphragms E, F, Fig. 1, controlling a gas valve L. The outer diaphragm chambers are connected by pipes e, f to the air pipe B at two points, one in front of and the other beyond the choke bore D, so that the valve L is affected by the difference between the pressures of the air at these points. The valve is affected also by variations of pressure in the gas pipe C, into which gas passes from the central chamber of the apparatus through the regulating-valve H. The leakage through the partition N where the diaphragm rod passes through it is not material. The part B' of the air pipe B may be coiled and heated by the furnace. In the modification shown in Fig. 2, the diaphragm E' is affected only by the difference of pressures in the air pipe B at the connexion e1 and at the choke bore D1, and the diaphragm F1 is affected only by the difference of pressures in the gas pipes C', C. The movement of the diaphragms E1, F1 opens the valve L5, which allows gas to escape from the chamber L' faster than it enters through the leakage port L4. The pressure of the gas in the pipe C' then lifts the diaphragm valve L1 from the seat L2. The flow of gas against the diaphra.gm F' then closes the valve L5 and afterwards the valva L'. The inlet end of the pipe e1 may be turned to face the stream, or placed otherwise.