A kind of backward type centrifugal blower
Technical field
The utility model relates to a kind of backward type centrifugal blower.
Background technique
Existing backward type centrifugal blower generally all is single air intake, and air quantity requires when big, the problem that the ubiquity noise is big.The general forward direction centrifugal fan that adopts of two air intake centrifugal blower fans, the blade quantity of the wind wheel of forward-type centrifugal blower is many, and interlobate distance is little, and manufacturing process is loaded down with trivial details, the product cost height.And the spiral case volume of forward-type centrifugal blower is bigger, and it is bigger to be installed in the space that occupies in the load, installs inconvenient.
Summary of the invention
The utility model provides air output big in order to overcome existing deficiency, and noise is little, and manufacturing process is simple, a kind of backward type centrifugal blower at the bottom of the cost of production.
In order to achieve the above object, the technical solution adopted in the utility model is: it is a kind of backward type centrifugal blower, comprises the electric machine support and the air-ducting ring of the spiral case of blower fan, back air intake wind wheel, motor, installation motor, is provided with an exhaust outlet on spiral case; It is characterized in that: have two wind inlets in the both sides of spiral case, air-ducting ring is installed in the wind inlet place; Both sides at back air intake wind wheel have two intake grills, and wind inlet is also big or small in correspondence with each other identical with being positioned at of intake grill.
Air-ducting ring and fixing is stretched out in the end of described electric machine support.
The utility model advantage compared with prior art is, the back to blower fan make two air intakes, can improve the air quantity of blower fan, the rotating speed of blower fan reduces simultaneously, and the noise of blower fan reduces greatly, and the quantity of the blade of the blower fan of backward type is few, manufacturing process is simple, has reduced the cost of product.Its spiral case is little with respect to the spiral case volume of forward-type, and the space that occupies is little, and is easy for installation, and simple shape, the stock utilization height, and the technology manufacturing is simple, has reduced the cost of product.
Description of drawings
Fig. 1 is an of the present utility model pair of air intake centrifugal blower fan schematic representation;
Fig. 2 is the utility model spiral case schematic representation;
Fig. 3 is the utility model centrifugal wind wheel schematic representation.
Embodiment
Below in conjunction with drawings and Examples the utility model is done further detailed description:
As shown in Figures 1 to 3, it is a kind of backward type centrifugal blower, comprises the electric machine support 2 and the air-ducting ring 1 of the spiral case 4 of blower fan, back air intake wind wheel 5, motor 3, installation motor, is provided with an exhaust outlet 41 on spiral case; The utility model characteristics are: have two wind inlets 42 in the both sides of spiral case 4, air-ducting ring 1 is installed in the wind inlet place, and air-ducting ring can reduce the resistance of air intake; Both sides at back air intake wind wheel 5 have two intake grills 51, and wind inlet is also big or small in correspondence with each other identical with being positioned at of intake grill.During work, motor 3 drives laggard wind wheel 5 and rotates, and wind sucks from wind inlet 42 and intake grill 51, blows out from exhaust outlet 41 by laggard wind wheel.Because two wind inlets are arranged on spiral case 4 both sides, laggard wind wheel 5 has two intake grills, balance is good during work, and noise is little, and the exhaust outlet of spiral case is big, and is simple in structure, volume is little, cost is low.
In the present embodiment, air-ducting ring 1 and fixing is stretched out in the end of electric machine support 2.