| 摘要 |
<p>COMBINATION PURGING AND VENTILATING BLOWER This invention relates to a blower which is specifically designed not only to purge a workplace of foul air preparatory to it being entered by personnel but also to provide these people with adequate ventilation once they are inside, such a blower being characterized by a hollow generally cylindrically-shaped open-ended outer housing having an intake end at the rear thereof and a discharge end in front, a collapsible purging hose with its rear end attached inside the outer housing adjacent the intake end of the latter and extendable out through its discharge end into a workplace to be purged, a generally frustoconical inner housing having its larger diameter intake end spaced to the rear of the intake end of the outside housing while at the same time cooperating therewith when positioned inside thereof to define one or more air-aspirating ports therebetween as well as an annulus for the storage of the purging hose in collapsed condition, a blower attached to deliver air to the intake end of the inner housing and cooperate therewith when the purging hose is extended to aspirate air into the latter through the air-aspirating ports as well as deliver air thereto, and a ventilating hose attachable to the relatively smaller discharge end of the inner housing for ventilating the workplace previously purged when the purging hose is stowed in collapsed condition.</p> |
