Built-in fan

A fan comprising fan wheel means, a housing means including a tubular member, said fan wheel means being supported substantially coaxially in said tubular member, said fan wheel means including a hub forming the rotor means of a centrally supported driving motor whose stator means is supported at the tubular member by generally radially directed spokes extending closely at one end of the fan wheel means, and fan blade means distributed over the circumference of the fan wheel means and extending in the space between the hub and tubular member to limit turbulence generated by adjacent fan blade means so that the turbulence is not in synchronism with the frequency of rotation of the fan blade means, the blade edges of adjacent fan blade means which face the spokes differing from one another with respect to a surface extending through the parts of the spokes closest to the fan blade edges as regards at least one of spacing, inclination, curvature, length and direction.

A fan comprising fan wheel means, a housing means including a tubular member, said fan wheel means being supported substantially coaxially in said tubular member, said fan wheel means including a hub forming the rotor means of a centrally supported driving motor whose stator means is supported at the tubular member by generally radially directed spokes extending closely at one end of the fan wheel means, and fan blade means distributed over the circumference of the fan wheel means and extending in the space between the hub and tubular member to limit turbulence generated by adjacent fan blade means so that the turbulence is not in synchronism with the frequency of rotation of the fan blade means, at least a part of the blade edges of adjacent fan blade means which face the spokes being of unequal construction.