GB673702A - Improvements in and relating to air dehumidifiers - Google Patents

Abstract

673,702. Drying air. BRITISH THOMSON-HOUSTON CO., Ltd. Sept. 27, 1949 [Oct. 9, 1948], No. 24789/49. Class 34(i). An air drying device of the kind including a drying agent, an electric heating element for heating the agent to re-activate it and a switch operated by change of weight of the drying agent, has a perforate container 8 containing silicagel 9 and resiliently mounted, a heating element 32, a switch 37 for energising the element and operated by the descent of the container and doors 52, 53 normally open but arranged to close in response to the rise of temperature caused by operation of the heating element and shut off the air space being dehumidified from the drying agent during re-activation. The container 8 has a bifurcated hinge 13 fitting over a bracket 16 and a spring 23 is hooked at its upper end into a hole 24 in a flange 25 of bracket 16 the lower end being adjustably secured to the side 12 of the container 8 by an eye bolt 26. A U-shaped electric heating element 32 is immersed in the desiccant 9 and a sensitive switch 37 adjustably attached to the cabinet wall has a switching arm 45 operated by a contact arm 44 attached to the top of the container 8. The front of the cabinet 5 is enclosed by hinged doors 52, 53 normally held open by arched arms 60, 61 of two or more dissimilar metals having different thermal co-efficients of expansion. Upon the application of heat these arms move inwards and allow the doors to close under the action of a spring 66, the upper part 57 of door 52 opening as the lower part closes. As the desiccant 9 absorbs moisture, its weight increases, causing the container 8 to descend against spring 23 and operate switch 37 to energise heater 32. Doors 52, 53 close to shut off the desiccant from the air being dried and the moisture laden air from the desiccant escapes through door 57 which is now open. As the moisture is driven off the container rises, shuts off the heater and as doors 52, 53 open again the drying cycle re-commences. Specification 283,470, [Class 34(i)], is referred to.