GB1339062A - Electric flow heaters - Google Patents

Abstract

1339062 Electrode boiler MARSTON EXCELSIOR Ltd 24 April 1972 [26 Jan 1971] 3168/71 Heading H5H An electric flow heater comprises a plurality of spaced electrodes 25, 28 mounted against the inclined walls of the flow chamber and displaceable along the walls to alter the spacing between the electrodes 25, 28. The chamber is predominantly frusto-conical with an upper cylindrical portion. Three equi-spaced electrodes are mounted in the chamber and each comprises a polypropylene support 25 whose rear surface engaging the wall of the chamber is of frustoconical shape. The active area of each electrode is formed by a titanium sheet 28 bent to form two flat surfaces 26. The titanium sheet has a surface coating of iridium, rhodium, an alloy of iridium and platinum or an alloy of iridium, rhodium and platinum. Each electrode is connected to the supply by a stud 31 secured to sheet 28 and an insulated wire 30 which extends through a circumferential conduit 33 on the outside of the chamber casing. Each electrode 25, 28 is biased towards an outlet 17 by a spring 35 which also biases it against the wall of the chamber. The axial position of the electrodes 25, 28 is adjusted by a nut 19 screwed on to the outlet 17. Movement of the nut is transmitted to the electrodes by push rods 40 extending through the upper wall of the casing. In an alternative embodiment, (Fig. 6, not shown), a coil spring biases the electrodes away from the outlet and separate coil springs between adjacent electrodes biases them against the frusto-conical surface of the chamber. The adjusting nut is mounted on the inlet and acts on the electrodes by means of push rods.