Walk-behind blower

Abstract

A walk-behind blower ( 10 ) having a plurality of impeller blades ( 34 ) mounted around a periphery of a rotating support structure ( 30,32 ) rather than on a rotating central shaft, and having an independent, wrap-around protective frame cage ( 18 ) which provides both a stronger mounting point for a front wheel ( 22 ) and skid protection for a housing ( 14 ). Each blade ( 34 ) presents a straight portion ( 48 ) beginning at an outer edge of a disk-shaped rear support structure ( 30 ) and extending inwardly, and a curved portion ( 50 ) beginning at an inward end of the straight portion.

1 . A blower for blowing debris, the blower comprising: 
 a housing presenting an intake opening; and    an impeller assembly for creating an air flow, the impeller assembly being located substantially within the housing, the impeller assembly including 
 a rear support structure having a substantially disk shape with a central area and a peripheral area surrounding the central area, with the central area being coupled with an engine, and  
 a plurality of impeller blades mounted spaced apart on the peripheral area of the rear support structure.  
   
   
   
       2 . The blower as set forth in  claim 1 , wherein the housing includes a shell and a duct extending around a periphery of the shell and terminating with an exhaust opening, with the shell presenting a first flattened end oriented substantially rearwardly and a second flattened end oriented substantially forwardly, and with the second flattened end presenting the intake opening.  
   
   
       3 . The blower as set forth in  claim 1 , wherein the rear support structure has a substantially conical cross-section with a slope of approximately between 30 degrees and 40 degrees.  
   
   
       4 . The blower as set forth in  claim 1 , wherein the impeller assembly further includes a front support structure having a substantially disk shape, with the plurality of impeller blades being mounted on and supported between the rear support structure and the front support structure.  
   
   
       5 . The blower as set forth in  claim 4 , wherein the front support structure presents an opening that substantially corresponds with the intake opening in the housing.  
   
   
       6 . The blower as set forth in  claim 1 , wherein each impeller blade presents a substantially straight portion and a substantially curved portion, with the curved portion being substantially concave in a direction of rotation.  
   
   
       7 . The blower as set forth in  claim 6 , wherein for each impeller blade 
 the straight portion begins at an outermost peripheral edge of the rear support structure and extends substantially inwardly at an angle of approximately between 20 degrees and 30 degrees relative to a radial axis defined by the rear support structure;    the curved portion begins at an inward end of the straight portion and is substantially concave over an arc that is approximately between 43 degrees and 53 degrees of a circle which has a center on the straight portion of an adjacent impeller blade and has a radius line extending perpendicularly from the straight portion of the adjacent impeller blade to the intersection of the straight and curved portions;    the impeller blade presents an attack angle of approximately between 10 degrees and 12 degrees; and    the impeller blade presents a pitch angle of approximately between 8 degrees and 10 degrees.    
   
   
       8 . A blower for blowing debris, the blower comprising: 
 a housing presenting an intake opening;    at least one front wheel; and    a frame cage extending substantially around a lower portion of the housing and coupled with the at least one front wheel, wherein the frame cage does not extend across the intake opening.    
   
   
       9 . The blower as set forth in  claim 8 , wherein the housing includes a shell and a duct extending around a periphery of the shell and terminating with an exhaust opening, with the shell presenting a first flattened end oriented substantially rearwardly and a second flattened end oriented substantially forwardly, and with the second flattened end presenting the intake opening.  
   
   
       10 . The blower as set forth in  claim 8 , wherein the frame cage extends around a first side of the lower portion of the housing, extends around a front portion of the housing below the intake opening, and then returns around a second side of the lower portion of the housing.  
   
   
       11 . The blower as set forth in  claim 8 , wherein the at least one front wheel is located substantially in front of and below the housing, and is pivotably mounted to the frame cage.  
   
   
       12 . An apparatus comprising: 
 a blower for blowing debris from an area with an air flow, the blower having an engine and a housing presenting an intake opening; and    an impeller assembly for creating the air flow, the impeller assembly being driven by the engine and located substantially within the housing, the impeller assembly including 
 a rear support structure having a substantially disk shape with a central area and a peripheral area surrounding the central area, with the central area being coupled with an engine, and  
 a plurality of impeller blades mounted spaced apart on the peripheral area of the rear support structure.  
   
   
   
       13 . The apparatus as set forth in  claim 12 , wherein the rear support structure has a substantially conical cross-section with a slope of approximately between 30 degrees and 40 degrees.  
   
   
       14 . The apparatus as set forth in  claim 12 , wherein the impeller assembly further includes a front support structure having a substantially disk shape, with the plurality of impeller blades being mounted on and supported between the rear support structure and the front support structure.  
   
   
       15 . The apparatus as set forth in  claim 14 , wherein the front support structure presents an opening that substantially corresponds with the intake opening of the housing.  
   
   
       16 . The apparatus as set forth in  claim 12 , wherein each impeller blade presents a substantially straight portion and a substantially curved portion, with the curved portion being substantially concave in a direction of rotation.  
   
   
       17 . The apparatus as set forth in  claim 16 , wherein for each impeller blade 
 the straight portion begins at an outermost peripheral edge of the rear support structure and extends substantially inwardly at an angle of approximately between 20 degrees and 30 degrees relative to a radial axis defined by the rear support structure;    the curved portion begins at an inward end of the straight portion and is substantially concave over an arc that is approximately between 43 degrees and 53 degrees of a circle which has a center on the straight portion of an adjacent impeller blade and has a radius line extending perpendicularly from the straight portion of the adjacent impeller blade to the intersection of the straight and curved portions;    the impeller blade presents an attack angle of approximately between 10 degrees and 12 degrees; and    the impeller blade presents a pitch angle of approximately between 8 degrees and 10 degrees.    
   
   
       18 . An apparatus comprising: 
 a blower for blowing debris from an area, the blower having a housing presenting an intake opening, and at least one front wheel; and    a frame cage extending substantially around a lower portion of the housing and coupled with the at least one front wheel, wherein the frame cage does not extend across the intake opening.    
   
   
       19 . The apparatus as set forth in  claim 18 , wherein the frame cage extends around a first side of the lower portion of the housing, extends around a forward portion of the housing below the intake opening, and then returns around a second side of the lower portion of the housing.  
   
   
       20 . The apparatus as set forth in  claim 18 , wherein the at least one front wheel is located substantially in front of and below the housing, and is pivotably mounted to the frame cage.