Air pump

Abstract

An improved air pump is composed of a shell, a rotor, and a lid. The shell includes a round chamber inside, an inlet and an outlet both running therethrough for communicating outside, and an axial hole positioned in the round chamber and having a different center from that of the round chamber. The rotor is disposed inside the round chamber, and includes a rotation shaft at the center thereof for inserting into the axial hole of the round chamber, three bevel slots recessed inwards from an outer periphery thereof, and three movable blades respectively mounted inside the three bevel slots and respectively moving frictionally along long axles of the bevel slots. The lid is coved on the shell to seal the round chamber.

1 . An air pump comprising: 
 a shell having a round chamber inside and an inlet and outlet both positioned at an inner periphery thereof and running through said shell to outside, said round chamber having an axial hole inside, said axial hole having a center different from that of said round chamber, the distance between said inlet and said axial hole being larger than that between said outlet and said axial hole;    a rotor received in said round chamber and having a rotation shaft protruding outwards from the center thereof for connecting an external power source, said rotation shaft being inserted into said axial hole of said round chamber, a plurality of bevel slots recessed inwards from an outer periphery thereof, each of said bevel slots having a long axle crossed with an tangential of the outer periphery of said rotor at a predetermined angle, and a plurality of movable blades respectively mounted in said bevel slots and moving outwards/inwards along the long axle of said bevel slot, whereby said blades will be centrifugally outthrowed while said rotor is rotated, and each have an outward end towards outside to engage against and move frictionally along the inner periphery of the round chamber; and    a lid covered on said shell to seal said round chamber, such that said round chamber communicates with outside merely via said inlet and said outlet.    
   
   
       2 . The air pump as defined in  claim 1 , wherein the predetermined angle at which the long axle of each said bevel slot is crossed with the tangential of the outer periphery of said rotor is an acute angle along a direction of the rotation of said rotor.  
   
   
       3 . The air pump as defined in  claim 1 , wherein the distance between said outlet and said axial hole is smaller than the radius of said round chamber.  
   
   
       4 . The air pump as defined in  claim 1 , wherein each of said blades is a long plate member.  
   
   
       5 . The air pump as defined in  claim 1 , wherein said shell further comprises a silencing filter at an outward end of said inlet.