Patent GB-872677-A (GB)
Title: Improvements in or relating to oil burner assemblies
IPC: F23D11/00
Filed: 1958-04-09
Abstract: 872,677. Liquid fuel burners. LJUNGMANS VERKSTADER A.B. April 9, 1958 [May 10, 1957], No. 11176/58. Class 75(1). In an oil fuel firing assembly comprising an oil burner, a suction pump 13, a feed pump 14. a mixing pump 15, a fan 16 for blowing primary and secondary air to the burner and an electric motor 17 for driving the pumps and the fan. the stationary parts of the pumps, the fan and the motor are assembled in line. the movable parts of the pumps, fan and motor are arranged on a common shaft 12, and all the parts are supported by a block 6 which is releasably clamped to two bolts 5 extending horizontally from a housing 1, 2 adapted to be mounted on the front of a boiler. The housing 1, 2 is in two separable parts, the front portion 2, being secured to the back portion 1 by nuts on the bolts 5. The three pumps 13, 14, 15 are arranged axially below each other in a common housing 18 secured to the underside of the supporting block 6. The motor 17 consists of a stator 24 secured to the upper side of the supporting block 6 and a rotor 25 secured to the common shaft 12. The fan 16 is secured to the upper end of the shaft 12 and is surrounded by a shell 26 secured to the top of the stator. The upper end of the shell has an end wall 27 which is sealingly inserted in a rubber packing 30 in the housing 1, 2 and which is provided with air inlet holes 28. A disc valve 31 is mounted above the end wall 27 and is raised and lowered, to uncover and cover the air inlet holes 28 therein, by an expansion bag 32 formed by two rubber membranes united along their common periphery, one membrane being attached to the disc valve 31, the other to the end wall 27 of the fan shell. The bag is supplied through a conduit 34 with air/oil mixture from the mixing pump 15. The upward movement of the disc valve is limited by a set screw 35 screwed into the housing. A bowl 19 is detachably secured by pivotally mounted U- shaped clamping members 20 to the underside of the pump housing 18 and contains a float 41 controlling a valve 42 at the inlet to an oil supply tube 40 connected to the inner 38 of two concentric burner tubes 38, 39 extending from the bowl to the burner. The outer burner tube 39 communicates with the upper space of the bowl 19. The burner tubes 38, 39 are surrounded by a large diameter tube 43 carrying secondary air from the housing 1, 2 to the burner. In operation the suction pump 13 draws oil from a tank (not shown) through a conduit 47 and delivers it to the feed pump 14 at a rate adjustable by a control means 48. Excess oil is returned to the tank through a conduit 49. The feed pump 14 delivers the oil through an oil meter 45 to a shallow recess 50 in the upper side of the supporting block 6. The recess 50 has an apertured cover through which air enters and the oil and air then flow together to the mixing pump 15. The mixture is delivered to the bowl 19' where liquid oil collects in the bottom and the finely dispersed oil in the space above. The pressure in the bowl causes the liquid oil to pass along the inner burner tube 38 and the dispersed oil along the outer burner tube 39. An ignition transformer 44 is located inside the housing 1,2.