| 摘要 |
630,173. Electric heating resistances. GOLDSTAUB, H. H. June 24, 1947, No. 16690. [Class 39(iii)] An electric heating device for laboratory or other flasks, comprises one or more layers a of knitted glass or like fibres shaped to conform to the exterior of the flask up to its maximum diameter and an electric heating element f disposed within or close to the layer of knitted fibres with which the flask shall be in contact. The heating element f consists of a spirally arranged resistance wire wound round and covered by asbestos or glass or like fibres. The heating device has a central hole d and is enclosed in a container i filled with glass fibre wool or other heat insulating material l. Specification 602,741, [Group VIII], and 623,786 are referred to. |
