Motorized portable blower apparatus

Abstract

A portable blower, and a fan for such a blower, are disclosed in which a plurality of blades extend from one side of a generally flat fan disc. The blades are swept rearwardly relative to the intended direction of rotation of the fan disc. The blades extend from the disc and are tilted transversely and in the direction of rotation of the disc. The tilt arises either due to manufacture or rotation of the disc and constitutes an air scoop for the fan.

1 . A portable hand-held blower comprising:
 a power source having an axis of rotation,   a fan mounted on said power source to be driven thereby and located within a housing, said housing having an array of inlet apertures and a single main exit,   a handle atop said housing and mounted substantially above the centre of gravity of said blower,   said main exit having a generally S-shaped configuration to substantially align the path of air exiting said blower with said handle to prevent a torque being experienced by an operator holding said handle in use, and   said fan being molded in a single piece from substantially rigid material; wherein said fan comprises:   a generally flat disc each quadrant thereof having a plurality of generally radially extending blades which all extend on the same side of said disc,   which all are rearwardly swept relative to the intended direction of rotation of the disc,   which all extend to a predetermined height above a plane passing through said disc and substantially perpendicular to said axis of rotation,   said blades being tilted transversely and in the direction of rotation of said fan either as a consequence of the manufacture of said blades, or as a consequence of the forces created by the operational rotational speed of said fan, and   whereby each transversely tilted blade and its adjacent portion of said disc in front of each said blade forms an air scoop for said fan.   
     
     
         2 . The blower as claimed in  claim 1  wherein said forces flex said adjacent portions of said disc in front of each said blade and each said flexed portion of said disc contributes to the corresponding said air scoop. 
     
     
         3 . The blower as claimed in  claim 1  wherein each said blade is manufactured to be upright relative to said disc. 
     
     
         4 . The blower as claimed in  claim 3  wherein each said upright blade is able to be tilted by said forces. 
     
     
         5 . The blower as claimed in  claim 4  wherein each said upright blade is tilted by said forces by bending at its base. 
     
     
         6 . The blower as claimed in  claim 4  wherein each said upright blade is tilted by said forces by bending above its base. 
     
     
         7 . The blower as claimed in  claim 1  wherein each said blade is manufactured to be tilted relative to said disc. 
     
     
         8 . The blower as claimed in  claim 1  wherein said fan has a side opposite said side carrying said blades, which is free of blades. 
     
     
         9 . The blower as claimed in  claim 1  wherein said blades have a perpendicular height above said disc of at least 30 mm. 
     
     
         10 . The blower as claimed in  claim 1  wherein said blades have a perpendicular height above said disc of at least 35 mm. 
     
     
         11 . The blower as claimed in  claim 1  wherein said blades have a perpendicular height above said disc of at least 40 mm. 
     
     
         12 . The blower as claimed in  claim 1  wherein said handle is mounted substantially above the centre of gravity of said blower. 
     
     
         13 . A fan for a blower, said fan comprising:
 a generally flat disc each quadrant thereof having a plurality of generally radially extending blades which all extend on the same side of said disc,   which all are rearwardly swept relative to the intended direction of rotation of the disc,   which all extend to a predetermined height above a plane passing through said disc and substantially perpendicular to said axis of rotation,   said blades being tilted transversely and in the direction of rotation of said fan either as a consequence of the manufacture of said blades, or as a consequence of the forces created by the operational rotational speed of said fan, and   whereby each transversely tilted blade and its adjacent portion of said disc in front of each said blade forms an air scoop for said fan.   
     
     
         14 . The fan as claimed in  claim 13  wherein said forces flex said adjacent portions of said disc in front of each said blade and each said flexed portion of said disc contributes to the corresponding said air scoop. 
     
     
         15 . The fan as claimed in  claim 13  wherein each said blade is manufactured to be upright relative to said disc. 
     
     
         16 . The fan as claimed in  claim 15  wherein each said upright blade is able to be tilted by said forces. 
     
     
         17 . The fan as claimed in  claim 16  wherein each said upright blade is tilted by said forces by bending at its base. 
     
     
         18 . The fan as claimed in  claim 16  wherein each said upright blade is tilted by said forces by bending above its base. 
     
     
         19 . The fan as claimed in  claim 13  wherein each said blade is manufactured to be tilted relative to said disc. 
     
     
         20 . The fan as claimed in  claim 13  wherein said fan has a side opposite said side carrying said blades, which is free of blades. 
     
     
         21 . The fan as claimed in  claim 13  wherein said blades have a perpendicular height above said disc of at least 30 mm. 
     
     
         22 . The fan as claimed in  claim 13  wherein said blades have a perpendicular height above said disc of at least 35 mm. 
     
     
         23 . The fan as claimed in  claim 13  wherein said blades have a perpendicular height above said disc of at least 40 mm.