Patent GB-257806-A (GB)
Title: Valves and valve operating devices for oil burners and the like
IPC: F23N5/00
Filed: 1926-01-05
Abstract: 257,806. Basel, E. A. Jan. 5, 1926. Liguid . fuel supply; overflow fittings. - A diaphragm supported valve controlling the flow of oil to a burner includes direct control means for operating the valve manually and electromagnetic operating means controlled by a thermostat. The valve is also closed on emergency conditions, such as the overnowing of oil on extinction of the flame or the melting of a fusible link. The valve 26 is carried by a resilient metal diaphragm and is urged outwardly by a spring 31 acting on a collar 30 on the outer end of the valve stem 27. A manually operable index-finger 34, screwthreaded on a tubular housing 32 for the valve stem and spring, is clamped by a screw 35 to a plug 33 which abuts against the collar 30 to close the valve. The index-finger 34 has a pivoted hasp 43 to engage with a screw pin 44 on a collar 45 which is clamped by a pin 44 to the hub of a weighted lever 40 operated by a chain 42. The finger 34 is set to the maximum desired opening and then connected by the hasp 43 with the lever 40. Adjustable stops for the lever are provided. For thermostat control the valve is actuated by a lever 58 pivoted at 59 in the valve casing and actuated electromagnetically through circuits controlled by a thermostat. The armature 72 of an electromagnet 70 displaces a pin 71 to actuate the valve-closing lever 58. This armature 72 carries contacts for the circuit of an electromagnet 69 the armature 76 of which carries contacts for the circuit of the first electromagnet 70. The two armatures are connected by a spring 74 and latch devices 78, 78<1> so that one armature is held up to its coil and prevented from movement until substantial movement of the other armature due to the attraction of its coil has taken place. The thermostat 91, Fig. 9, is provided with electromagnets 89, 100 whereby the thermostat contacts 90 or 101 are firmly made. The valve-actuating lever 58 is provided with an adjusting screw 64 and with a retarding device consisting of a diaphragm chamber having a small air vent with a pivoted lever attached at one end to the diaphragm and at the other end to the actuating lever. When a blower is used for spraying the oil the motor is controlled by a rocking mercury switch 120 connected to an arm on the magnet armature 76 through a spring connection. Any oil overflowing from the burner is returned by a pipe 127 to a bucket 130 carried by a counterweighted lever 131 pivoted on another counterweighted lever 133, which turns about a pivot 134 and has a fingerpiece 136 engaging the lower end of the valveactuating lever 58. A link 137 which engages with a pin 144 on the bucket lever 131 normally supports the two levers, but on the filling of the bucket the link 137 is displaced from the pin whereupon the two bucket-supporting levers are released and the valve is closed by the pressure of the lever finger 136 on the valve lever 58. A similar action takes place if a fusible link which retains an arm carrying the supporting link 137 melts. The blower is stopped on either of these emergency operations by means of a connection from the counterweighted lever which tilts the mercury switch to open the motor circuit independently of any action of the electromagnets 69 or 70 which takes place through the spring connection which yields. An oil screen 20 is fitted to which access may be had by removing a plug 22.