Impeller arrangement

Abstract

An impeller arrangement for location for use with a blower and/or vac device, the impeller being rotatable about an axis of rotation and comprising a base, a shroud and a plurality of blades located therebetween, the shroud comprising an impeller inlet defining a passageway to the plurality of blades, a barrier arrangement located adjacent the impeller inlet to restrict airflow between the impeller and its housing. By providing such an arrangement, inlet losses to the impeller can be reduced when compared to known arrangements. The interaction between these components forms a barrier to bleeding of the airflow away from the inlet, reducing the likelihood of air passing between the impeller and its housing and improving the inlet efficiency of the impeller.

1 . An impeller arrangement comprising an impeller located in a volute of a device, the impeller being rotatable about an axis of rotation and comprising a base, a shroud and a plurality of blades located therebetween, the shroud comprising an impeller inlet defining a passageway to the plurality of blades, wherein the impeller interacts with a portion of the volute surrounding the impeller inlet to form a barrier arrangement located adjacent the impeller inlet to restrict airflow between the volute and the shroud. 
     
     
         2 . The impeller arrangement according to  claim 1 , wherein the barrier arrangement forms a convoluted air path. 
     
     
         3 . The impeller arrangement according to  claim 2 , wherein the barrier arrangement comprises the shroud forming an annular channel which receives a portion of the volute therein. 
     
     
         4 . The impeller arrangement according to  claim 3 , wherein the shroud comprises two parallel spaced ribs defining the channel therebetween. 
     
     
         5 . The impeller arrangement according to  claim 4 , wherein the volute includes a rib that is located within the channel formed by the shroud to form the convoluted air path. 
     
     
         6 . The impeller arrangement according to  claim 5 , wherein the volute comprises a scroll-type volute outlet downstream of the impeller. 
     
     
         7 . An impeller for a blower device, the impeller being secured to a drive shaft of a motor and rotatable about an axis of rotation, the impeller comprising a base, a shroud and a plurality of blades located therebetween, the shroud comprising an impeller inlet defining a passageway to the plurality of blades;
 wherein the impeller interacts with a portion of the volute surrounding the impeller inlet to form a barrier arrangement located adjacent the impeller inlet to restrict airflow between the volute and the shroud.   
     
     
         8 . The impeller according to  claim 7 , wherein the shroud includes a pair of parallel ribs that interact with a rib on the volute to form the barrier arrangement.