GB813461A - An improved cut-out arrangement for electrical heating apparatus - Google Patents

Abstract

813,461. Electric water heaters. MORLEY PRODUCTS (PADIHAM) Ltd. May 9, 1957 [May 9, 1956], No. 14358/56. Class 39(3) [Also in Group XXXVII] A water tank 10 e.g. a wash boiler carries two sheathed heating elements 12, 13, one of which is provided with a lever system whereby on expansion of the heating element should it not be covered with water, a cut-out switch 34 is operated to end the heating. Switches 32, 33 energize the elements which are mounted at 14 to pass up through the bottom of the tank and extend parallel to the bottom wall, which has a water outlet 14. A plate 16 is welded to the free end of the element 12, which moves due to expansion of the element on over-heating. A pin 18 on a short arm 19 of a lever extends into a slot 17 in the plate 16 so that on expansion of the element, the arm 19 moves a pivot shaft 20 mounted vertically and rotatably in a gland 21 on the bottom of the tank to extend therethrough. The arm 19 is fixed by a locking screw 26 to the shaft 20, to which below the tank is secured a longer lever arm 27. To the lower end of the arm 27 is attached a connecting rod 30, the other end of which carries a hook 36 engaging a tongue 35 of the cut-out switch 34. A nut 37 is moved on a threaded part of the rod 30 to adjust the temperature of operation of the switch 34. The angular movement on expansion due to over-heating of a spiral sheathed element 13, on which a short arm equivalent to the arm 19 could be directly attached, operates the cut-out switch 34. A false perforated bottom may extend across the boiler above the heating elements.