GB982516A - Apparatus for controlling liquid feeding systems - Google Patents

Abstract

982,516. Supplying liquid fuel to burners. SWF-SPEZIALFABRIK FUER AUTOZUBEHOER GUSTAV RAU G.m.b.H. Dec. 11, 1963 [Jan. 19, 1963], No. 49038/63. Heading F4T. [Also in Division G3] In an apparatus for controlling the supply of fuel oil to burners (not shown) comprising a pump 2 pumping the oil from a main storage tank to an intermediate container 5 having a variable volume, the motor 1 driving the pump is controlled by a toggle switch 18 actuated by the change in volume of the intermediate container 5. The pump delivers the oil through a check valve 4 to the intermediate container and a pressure line 19 conveys the oil from the intermediate container to the burners. The intermediate container may be a cylinder closed by a piston or, as shown, a cup-shaped flexible diaphragm 9 inside a housing 6, 7 containing a piston 10 having a rod 11 extending through an aperture in the bottom of the housing. A plurality of tension springs 13 extend between the bottom of the housing and a disc 12 adjustably secured to the piston-rod 11. The piston carries an arm 15 having adjustable cross-arms 16, 17 adapted to operate the toggle switch 18. When the pump is working the diaphragm pushes the piston downwardly against the action of the tension springs 13 until the crossarm 16 flips the toggle switch 18 to switch off the motor 1. As the oil is consumed the piston rises and the other cross-arm 17 actuates the toggle switch in the opposite direction to switch on the motor. If the volume of oil in the intermediate container falls below a certain value a safety switch 22 in series with the motor switch 18 is opened by a further cross-arm 24 on the arm 15 to stop the pump. The safety switch 22 may also start an acoustic or optical alarm. After the cause of the low oil volume has been removed the apparatus is started by a pushbutton which bridges the safety switch 22. A further cross-arm 23 then closes the safety switch 22. A further safety switch 21 is actuated by a further cross-arm 25 to switch off the apparatus if the maximum volume of oil in the intermediate container is exceeded. The arm 15 and cross-arms may be replaced by a plurality of rods slidable in bores in the bottom of the housing 6, 7 and urged upwardly by springs. Adjustable collars on the rods engage the bottom of the housing. The piston depresses the rods successively and each rod has adjustable crossarms for actuating a toggle switch. In a modification, Fig. 3 (not shown), the tension springs are replaced by a flexible container filled with air and a further piston is provided to compress the air as the oil increases the volume of the intermediate container. An arm on the double piston extends through a slot in the outer casing to operate four switch control rods.