Patent GB-849757-A (GB)
Title: Improvements in or relating to oil burner units
IPC: F23D11/36
Filed: 1958-05-02
Abstract: 849,757. Supplying liquid fuel to burners. LINDE R. VON, May 2, 1958 [May 3, 1957 ; June 8, 1957], No. 14026/58. Class 75(7). An oil burner unit comprising a verticalshaft electric motor 1, the shaft 3 of which is capable of slight axial movement, in which, above the motor, the shaft 3 has mounted thereon a fan 7 to supply combustion air and, below the motor, has mounted thereon the rotor 19 of a rotary oil pump 20 which draws oil from an external storage tank and delivers it to an oil chamber or vessel 24 from which the burner nozzle 31 is supplied had the entry of oil into the chamber or vessel controlled by a device within such chamber or vessel. This device may prevent further oil being drawn from the external storage tank until the oil to be supplied from the chamber or vessel is under adequate pressure for delivery to the burner nozzle. This pressure may be provided by the air pressure set up in the chamber or vessel by a blower 9 providing atomizing air for the nozzle 31 or by the delivery pressure of a further rotary pump 52, Fig. 2, which feeds a spray nozzle 63 and the rotor 50 of which is also mounted on the vertical shaft 3 but disposed below the rotary pump (51 in Fig. 2) drawing oil from the external storage tank. The slight axial movement possible for the motor shaft 3 and the use of a flexible coupling 16, Fig. 1, 47, Fig. 2, in the drive to the pump rotors avoids the necessity for precision fitting and permits the rotor and casing of one of the rotary pumps to serve as a thrust bearing for the shaft. The blower 9 and rotary pump 20 of Fig. 1, and the two rotary pumps 51, 52 of Fig. 2 are contained within the chamber or vessel 24 of Fig. 1, and 59 of Fig. 2. The control device shown in Fig. 1 is a valve 39 attached to a spring-loaded diaphragm which is subjected to the oil pressure and only when the oil pressure is sufficient does the valve open the suction intake 40 to the rotary pump to permit further oil to be drawn from the external storage tank and delivered into the chamber or vessel 24 where the oil is under the pressure given by the atomizing air from the blower 9. A float-controlled valve 41 in the rotary pump suction intake closes the intake when a predetermined level is reached. The control device shown in Fig. 2 is a combined shut off and throttling member and comprises a spring- loaded piston-like member 72 necked intermediate its length at 82 and on its bottom face having a spigot 74 passing through a gland 75 and serving to close an inlet from the external storage tank. When the oil pressure on the delivery side of the rotary pump 52 supplying the spray nozzle 63 rises to a sufficient value the piston-like member 72 rises and removes the spigot from its seating whereupon the other rotary pump 51 can draw oil from the external storage tank to deliver to the chamber or vessel 59. The upward movement of the piston-like member 72 if sufficiently continued will throttle the oil passing by the passageway 64 to the inlet side of the rotary pump 52 for delivery to the nozzle ; this throttling action tends to maintain a constant pressure in the delivery to the nozzle. Upstanding from the piston-like member 74 is a rod 76 which will open the covering 71 of the inlet to the fan supplying the combustion air only when the oil pressure to the nozzle 63 is sufficiently high. As a precaution against the float sticking and failing to close the valve 41 (or the similar valve 78, Fig. 2) a second float may act to shut down the electric motor or there may be an auxiliary oil pump on the motor shaft having a suction inlet above the normal oil level the pressure oil from such auxiliary pump acting (when present) to close the inlet to the oil replenishment pump.