Electric motor housing

Abstract

A housing for an electric motor for driving a fan for a vacuum cleaner, comprising respective parts fitting together so that at least part of the housing comprises spaced inner and outer walls between which exhaust flow of air from the fan takes place, wherein there is provided at least one formation extending into the space between the inner and outer walls to cause the air to flow in an elongated flow path therebetween.

1 - 11 . (canceled)  
   
   
       12 . A housing for an electric motor driving a vacuum cleaner fan, comprising spaced inner and outer walls receiving exhaust air flow from a fan, and at least one formation extending into a space between the inner and outer walls to define an elongated flow path therebetween.  
   
   
       13 . A housing of  claim 12 , wherein the spaced inner and outer walls are generally cylindrical defining an annular space therebetween.  
   
   
       14 . The housing of  claim 13 , wherein at least a portion of the air flow is in a circumferential direction within the annular space.  
   
   
       15 . The housing of  claim 14 , wherein at least a portion of the air flow is in a helical direction within the annular space.  
   
   
       16 . The housing of  claim 12 , wherein the at least one formation comprises at least one rib or vane extending from one of the inner and outer walls into the space between the inner and outer walls thereof.  
   
   
       17 . The housing of  claim 16 , wherein the at least one rib or vane is at least partially helical.  
   
   
       18 . The housing according to  claim 16 , wherein the at least one rib or vane comprises four ribs or vanes that are substantially evenly spaced apart along the circumference of the inner wall.  
   
   
       19 . The housing of  claim 12 , further comprising an electric motor provided within the housing for rotating the fan.  
   
   
       20 . The housing of  claim 12 , wherein the formation extends radially from the inner wall toward the outer wall.  
   
   
       21 . The housing of  claim 20 , wherein the formation contacts or is in substantially close proximity to the outer wall.  
   
   
       22 . The housing of  claim 16 , wherein the at least one rib or vane extends radially and helically from the inner wall toward the outer wall.  
   
   
       23 . The housing of  claim 22 , wherein the at least one rib or vane extends at a varying curvature along the length inner wall.  
   
   
       24 . The housing of  claim 12 , wherein the formation extends along approximately two thirds of a length of the inner wall.  
   
   
       25 . The housing of  claim 12 , wherein the formation engages a lug that extends radially outward from the inner wall, the lug connecting the inner wall to the outer wall.