(under subclass 251) Subject matter wherein the air moving means directly contacts air to force it into the ventilated space and directly contacts air to force it out of the space.
(1) Note. While most subject matter in this subclass comprises a means for contacting and forcing the air into the ventilated space and a separate means for contacting and forcing air out of the space, subject matter comprising a single means which performs both functions is also included herein.
SEE OR SEARCH THIS CLASS, SUBCLASS:
235, for subject matter having forced recirculation and both inlet and outlet airways, and further having air pump means for both of the airways, which airways are contained in a unitary housing.
244, for a sleeved vent for a ceiling, wall, or floor with air pump means for both inlet and outlet airways.
