LOW-NOISE FUME EXTRACTOR HOOD

摘要

A fume extractor hood is disclosed, comprising a box with a motor-fan assembly and a muffler module comprising a bearing frame defining an air extraction conduit with axis (A), an active noise suppression system comprising at least one electro-acoustic transducer and at least two microphones, a passive noise suppression system comprising a sound absorbent material. Said muffler module comprises at least two electro-acoustic transducers connected to the walls of said bearing frame, in opposite positions, in such manner to leave the central part of said conduit free. The sound beams coming from said at least two electro-acoustic transducers are mutually combined, obtaining a resulting sound beam that can be directed towards a preferred direction by means of beam forming algorithms.

主权项

1. A fume extractor hood comprising:
a box containing a motor-fan assembly comprising a motor that actuates at least one fan; and a muffler module disposed under said box of the motor-fan assembly, said muffler module comprising:
a bearing frame defining an air extractor conduit with axis (A);an active noise suppression system comprising at least two electroacoustic transducers and at least two microphones connected to a control unit;a passive noise suppression system comprising sound absorbent material disposed between said microphones characterized in thatsaid two electro-acoustic transducers are connected to the walls of said bearing frame, in opposite positions with respect to the axis (A) of the conduit, in such manner to leave the central part of said conduit free;each electro-acoustic transducer having a sound emission surface inclined by an angle (θ) higher than 0° with respect to the axis (A) of the conduit to generate a sound beam with axis (S) inclined by an angle (α) lower than 90° with respect to the axis (A) of the conduit, in such manner that the sound beams coming from said two electro-acoustic transducers can be mutually combined, obtaining a resulting sound beam that can be directed in a preferred direction, by means of beam forming algorithms.