Abstract: A ventilating fan includes a sirocco fan disposed in a box-shaped body and an adapter connected to an air outlet of the sirocco fan. The sirocco fan is composed of two opposite scroll plates with scroll shapes and a casing plate sandwiched between the two scroll plates. An overall air inlet of the sirocco fan is disposed on the first scroll plate and a central line of the air outlet of the adapter is offset towards the second scroll plate. The present invention is advantageous in that no turbulence is generated at the adapter and the wind amount of the ventilating fan is thus ensured and noise is reduced. Therefore, the present invention can provide a small air blowing device with high efficiency and improve stability of performance of the product.

Abstract: Disclosed is a structure for reducing noise of a ventilating fan. The structure includes an orifice plate fixed on a scroll casing and is shaped to be an annular and semi-surrounding hollow structure in order to match with the shape of an air inlet of the scroll casing, and to cover only the air inlet of the scroll casing. The noise generated by an air blower of the ventilating fan can be directed along a bell mouth of the scroll casing of the ventilating fan after being emitted from the air inlet of the scroll casing, and then can be smoothly sucked by the orifice plate. The sucked-in noise can repeatedly collide with the orifice plate and be diffused, thereby the energy being gradually weakened and the sound pressure thereof being decreased.

Abstract: Disclosed is a structure for reducing noise of a ventilating fan. The structure includes an orifice plate fixed on a scroll casing and is shaped to be an annular and semi-surrounding hollow structure in order to match with the shape of an air inlet of the scroll casing, and to cover only the air inlet of the scroll casing. The noise generated by an air blower of the ventilating fan can be directed along a bell mouth of the scroll casing of the ventilating fan after being emitted from the air inlet of the scroll casing, and then can be smoothly sucked by the orifice plate. The sucked-in noise can repeatedly collide with the orifice plate and be diffused, thereby the energy being gradually weakened and the sound pressure thereof being decreased.

Abstract: A ventilating fan includes a sirocco fan disposed in a box-shaped body and an adapter connected to an air outlet of the sirocco fan. The sirocco fan is composed of two opposite scroll plates with scroll shapes and a casing plate sandwiched between the two scroll plates. An overall air inlet of the sirocco fan is disposed on the first scroll plate and a central line of the air outlet of the adapter is offset towards the second scroll plate. The present invention is advantageous in that no turbulence is generated at the adapter and the wind amount of the ventilating fan is thus ensured and noise is reduced. Therefore, the present invention can provide a small air blowing device with high efficiency and improve stability of performance of the product.

Abstract: A ventilator (100) includes a frame (10), a volute (20) mounted in the frame (10), a motor bracket (60) mounted in the opening of the volute (20) and a motor (30) fitted in the motor bracket (60). The frame (10) is made of metal material. The character of the ventilator is in that the motor bracket (60) is made of metal material. Since the metal motor bracket has favorable performances of heat radiation and rigidity, the ventilator (100) has better security and stability.

Abstract: A temperature protection device for a brushless DC Motor, wherein a thermal fusing type protector is provided at a depression formed on a casing of the plastic-packaged brushless DC Motor. In this way, the thermal fusing type protector can be provided conveniently at a position where the casing temperature is highest after plastic packaging, and if the protector is fused due to high temperature, it can be replaced easily.

Abstract: A temperature protection device for a brushless DC Motor, wherein a thermal fusing type protector is provided at a depression formed on a casing of the plastic-packaged brushless DC Motor. In this way, the thermal fusing type protector can be provided conveniently at a position where the casing temperature is highest after plastic packaging, and if the protector is fused due to high temperature, it can be replaced easily.