Insulating structure for motor driven ventilating fan, comprises internal, intermediate and external motor containers, the intermediate container having the highest coefficient of attenuation

摘要

An electric ventilating fan motor (2) is supported within internal (6), intermediate (5) and external (4) concentric containers. The external container has a flanged rim (7) for fixing and is made of poypropylene as is the internal container. The intermediate container is made from an elastomer or a rubber which has a higher coefficient of attenuation than that of the internal and external containers