Patent GB-301875-A (GB)
Title: Improvements in and relating to heating systems
IPC: F24D9/02
Filed: 1928-12-05
Abstract: 301,875. Halsey, E. S. Dec. 7, 1927, [Convention date]. Heating buildings.-A steam heating plant, Fig. 1, comprises a basement boiler A, directheating radiators B, and a radiator HA which heats the air supplied to the room above. Air may be admitted to the base of the radiator HA either by a passage F leading from the room, or by a passage CA from outside, according to the position of the damper D. A thermal switch T' is provided in the room, adapted at a predetermined temperature to close the circuit of an electromagnet M which controls a fluid pressure device adapted to operate a damper D and thus admit fresh cold air through inlet CA to the radiator HA, and thence into the room. The air from the room is discharged through opening FA. The radiators B are controlled by a thermal switch T which at a predetermined temperature completes the circuit of electromagnets M which control fluid pressure devices adapted to close the steam admission valves V of the radiators. If steam should pass through the outlets E of the radiators while the temperature is still too low, thermal switches T' are actuated to close the admission valves V through the same electromagnetic devices. The construction of the valve V is shown in Fig. 2. The casing is closed at its outer end by a plate X to which a flanged snapaction diaphragm 5 is secured so as to enclose a space 1. This space is connected by tubes 7, 8 to a chamber 2 formed by a vertical bore in a square brass column 9, attached to cooling plates 10 of iron and 11 of brass. The lower portion of the chamber 2 contains a ball valve 3 adapted to be lifted by an external electromagnet M, the magnetic circuit of which includes the plate 10, a forked extension of the core 13, and two studs which project inwards through the column 9. A heat-insulating disc 15 is arranged as shown. The chambers 1, 2, contain alcohol, so that when the valve 3 is closed and the diaphragm 5 is subjected to steam heat, the alcohol in chamber 1 is evaporated, and the vapour passes through the tube 7 and condenses in chamber 2 until only vapour remains in chamber 1, and the internal pressure is relatively low. When the thermal switch T or T' energizes the electromagnet M, the valve 3 is opened, and alcohol flows into the chamber 1, so that the internal pressure is raised and maintained. The diaphragm 5 is deflected outwards to move the plunger 16 against the points 17<1> of the short arm of a weighted fork lever 17 pivoted at 17a on a pin sliding in slots 21. The pin is carried by a spring pressed collar and is maintained in its extreme right hand position during the initial movement of the lever 17 and forked link 18 which operates the valve 22. A rapid closing movement of the valve is thus effected by the toggle action of levers 17, 18, until these levers are in line. The final closing is effected by the movement of the levers as a whole, the pin 17a sliding in its slots against the action of the spring. The closure surface of the valve 22 is of yielding material. When the temperature in the room allows the switch T or T<1> to open, the ball valve 3 falls, and the vapour pressure is soon reduced by distillation of the alcohol from chamber 1 to chamber 2, so that the weighted lever 17 opens the steam valve 22. The member 34 carrying the valve is internally threaded to form an adjustable connection with the threaded stem 23, and a locking pin is provided to secure the parts in adjusted position. The device M which actuates the damper D is similar in construction, except for the manner of supplying heat to the alcohol. In this case (Figs. 9 and 10, not shown), the plate X contains an annular chamber which is connected to a steam pipe. The thermal device fitted to the radiator outlet E is illustrated in Figs. 11 and 12. A horizontal tube H is sealed at its outer end by a large cooling disc H<1>, adjacent to a thermosta,tic capsule T' or bimetallic device adapted to actuate a switch arm A at a temperature of 160‹-180‹F. preferably with a snap action. When the radiator is filled with steam, but with no steam passing through the outlet E, the capsule T<3> is at about 110‹F. but if steam displaces air out of the horizontal tube H by difference of density, the capsule T' is raised to about 210‹F., and the arm A is raised to break contact with the wire T" from the room thermostats, and make contact with the wire B<11> so as to energize the electromagnet M and close the steam supply valve 22 until the plate H<1> has cooled sufficiently to restore normal conditions. The tube H may be in any position so long as the closed end is not lower than the open end.