4results about How to "Reduce eddy current noise" patented technology

The utility model provides a kind of heat dissipation device of electric control board and range hood comprising it, heat dissipation device includes two interval cover metal cover, drain pipe and heat dissipation fan, electric control board is enclosed in second metal cover;The sidewall of first metal cover is equipped with heat dissipation air inlet, and the shell of main fan is equipped with heat dissipation air outlet;The air outlet of heat dissipation fan is communicated with heat dissipation air inlet;The inlet of drain pipe is communicated with heat dissipation air outlet, and the outlet of drain pipe extends to the import negative pressure area of main fan.The heat dissipation device of electric control board and range hood comprising it, while protecting electric control board from being contaminated, accelerate the airflow speed in heat dissipation air duct, so that heat is discharged faster, improve overall heat dissipation effect.By setting drain pipe, while dissipating heat, the negative pressure area of main fan air inlet can also be air-supplied, reduce eddy current noise, improve the overall efficiency of range hood.

The utility model discloses a movable impeller of a fan and the fan thereof. The movable impeller comprises a movable impeller upper end disc and a movable impeller lower end disc which are respectively distributed at intervals up and down, a movable impeller air inlet is formed in the center of the movable impeller upper end disc. A lower end disc of the movable impeller is fixedly connected with an output shaft of the fan motor; a plurality of movable impeller blades distributed in an arc shape are arranged between the movable impeller upper end disc and the movable impeller lower end disc, and movable impeller air outlets are formed between the outer sides of the adjacent movable impeller blades; an air guide structure close to the movable impeller air inlet is arranged on the inner side of each movable impeller blade, and the air inlet angle of each air guide structure is set to be 95-100 degrees, preferably 96-99.5 degrees and more preferably 96-99 degrees; according to the fan adopting the movable impeller, the working noise of the fan can be obviously reduced.

The application provides a register, an indoor unit and a control method, wherein the register is provided with a gap extending along a first direction, the gap separates the register into a front edge part and a main body part in a register direction, and the first direction is perpendicular to the register direction; in a cross section perpendicular to the first direction, the cross section profile of the main body part is a first airfoil profile, the head of the first airfoil profile is located at a side of the main body part close to the front edge part, the cross section profile of the front edge part outside the gap is a head profile of a second airfoil profile, the included angle of the chord line of the front edge part and the chord line of the main body part is β, the chord length of the front edge part is L1, the width of the narrowest part of the gap is L2, and the chord length of the main body part is L3; β = 10-30°, and L3 = 6L1-10L1, L1 = 2L2-5L2. According to the application, the flow blockage of the leeward surface of the register can be reduced, the air volume of the register is almost not attenuated when the register is deflected at a large angle, and the air supply volume of the register is improved; and the unsteady vortex flow can be avoided, and the vortex noise generated by the register is reduced.