Patent GB-368004-A (GB)
Title: Automatic gas and water regulator for water heaters
IPC: F24H9/20
Filed: 1931-01-21
Abstract: 368,004. Fluid-actuated valves. HAHN, O. W., 1675, Pacific Avenue, San Francisco, U.S.A. Jan. 21, 1931, No. 2022. [Class 135.] In an automatic regulator for a water heater of the kind having interconnected gas and water valves actuated by the water flow, a retarding mechanism is interposed between the two valves and adapted fully to open the gas valve on the initial movement of the water valve, but to delay for a predetermined time the complete opening of the water valve. In the construction shown in Fig. 1, gas and water piston valves 3, 7 respectively working in cylindrical sleeves 18, 15 are arranged between the inlets 4, 8 and outlets 5, 9 and are automatically operated by the opening or closing of a water faucet connected with the hot water coils. Under water pressure the valve 7 is designed to be displaced against the action of a spring 17 and coacts with a tapering slot 16, Fig. 4, in the sleeve 15, the initial portion of the movement prior to the valve reaching the commencement of the slot 16 taking place without permitting the passage of any water. A spindle 13 attached to the valve 7 is connected to the external casing 30 of the retarding mechanism or dashpot, the piston 33 of which is connected to a spindle 10 attached to the gas valve 3. The latter valve co-operates with a series of holes 19, Fig. 6, or slots 19<1>, Fig. 7, in the sleeve 18 for the automatic regulation of the gas supply, while an external non- automatic regulation of the gas supply according with maximum temperature requirements can be effected by rotating the sleeve 18 from a handle 27. Oil or like fluid 37 disposed in the dashpot casing passes to the upper portion thereof via a passage 36 through the spindle 10 and is capable of returning slowly to the lower portion through a small ball-controlled aperture 34. In operation, assuming the valves 3, 7 to be initially at their extreme lower positions, if the water faucet is opened, the valves and dashpot are lifted almost rigidly, but the gas valve alone is opened, the opening of the water valve being delayed until sufficient fluid in the dashpot has been displaced to the upper side of the piston 33 to allow the valve 7 to reach the lower end of the slot 16. The actual rates of flow of gas and water are in proportion, and are regulated by the extent of opening of the water faucet, while upon closure of the latter, springs 22, 17 reclose the valves 3, 7, the subsequent action of which is dependent upon the time that elapses before the next opening of the water faucet. If this interval is a long one, the whole of the fluid in the dashpot will have returned to the lower portion of the casing, and all the parts 3, 7, 30 will be restored to their initial positions, such procedure corresponding to the time that the water coils require for cooling off ; if, however, the interval is shorter one, the valve 7 will be only a small distance below the lower edge of the slot 16, so that, on reopening the water faucet, the water valve 7 will reopen immediately or with less delay than in the previous instance. Gas for a pilot light is supplied by a duct 29 and outlet 28, and the supply is rapidly augmented by the displacement of the gas valve 3 when the water faucet is opened. A modified form of dashpot is described and, in a further construction, the dashpot fluid is drawn from the water flow under regulation.