Patent Publication Number: US-2005132531-A1

Title: Portable blower

Description:
CROSS REFERENCE TO RELATED APPLICATION  
      This application claims priority of German patent application no. 103 59 749.2, filed Dec. 19, 2003, the entire content of which is incorporated herein by reference.  
     BACKGROUND OF THE INVENTION  
      A known portable blower includes a handle with which the blower can be guided manually. Blowers are also known which can be carried on the back of an operator. Blowers of this kind can be used in many ways because the operator is not dependent upon easily accessible ground such as pathways or the like as is the case in moveable blowers. However, the operator must always carry the blower. This leads to rapid fatigue of the operator.  
     SUMMARY OF THE INVENTION  
      It is an object of the invention to provide a portable blower of the kind referred to above which can be used in many ways and which reduces fatigue of the operator.  
      The portable blower arrangement of the invention includes: a blower unit including a housing; a device for guiding the blower unit on the ground; and, means for attaching the device to the housing.  
      A device for guiding the blower unit over the ground can be fixed to the housing of the blower unit. In this way, the blower unit can be converted into a ground-guided blower unit in a simple manner. When used as a ground-guided blower unit, the operator need not carry the weight of the apparatus whereby the load on the operator is considerably reduced. In this way, fatigue-free utilization of the blower unit is possible. In inaccessible terrain, the device can be separated from the blower unit and the blower unit can be used as a portable blower unit. In this way, the blower unit can be used in many ways.  
      During operation, the blower unit blows out air through a discharge pipe which is configured as a short stub. The blower arrangement has a blower tube which can be releasably attached to the discharge pipe. In order to use the blower unit as a back-carried blower unit, a blower tube is needed which conducts the air flow, which is generated by the blower unit, around the body of the operator toward the front so that the operator can direct the air flow to the location of utilization. With the blower tube, considerable flow losses, however, result. To reduce these flow losses when utilizing the blower unit as a ground-guided blower unit, the blower tube is attached to the discharge pipe so as to be releasable so that the blower unit, when utilized as a ground-guided blower unit, can be utilized without the blower tube. With the configuration of the discharge pipe as a short stub, considerable increases in performance are obtained when utilizing the blower unit as a ground-guided blower arrangement compared to the use of the blower unit having the blower tube.  
      Advantageously, the blower unit has an operator-controlled unit with a throttle lever with this operator-controlled unit being releasably fixable to the blower arrangement. The disposition of the operator-controlled unit on the arrangement makes possible a simple, ergonomic handling during operation of the blower unit as a ground-guided blower arrangement. The operator-controlled unit includes a collar for fastening the operator-controlled unit to the blower tube. In this way, an ergonomic handling is made possible also during use of the blower unit as a back-carried blower unit. The collar functions to fix the operator-controlled unit to the blower tube as well as to fix the operator-controlled unit to the apparatus. The blower unit can therefore be used as a back-carried blower unit as well as a ground-guided blower unit without additional devices being needed for the conversion. The blower arrangement advantageously includes a device configured as a moveable rack. The housing includes a back-carrying plate for carrying the blower unit on the back. In this way, the blower unit can be guided on the ground as well as being carried on the back of an operator because the blower unit has a back-carrying plate and is releasably attachable to the device, especially on the moveable rack.  
      A simple configuration of the blower unit results when the device can be fixed to the back support plate. The back support plate has especially a handle on which the back support plate can be attached to the moveable rack. A handle of this kind is usually provided for back-carried blower units so that the blower unit can be held in a simple manner as long as it is not carried on the back. This handle is used in order to fix the blower unit to the moveable rack. In this way, no additional devices of the blower arrangement such as attachment means or the like are needed for the attachment of the blower unit to the moveable rack.  
      A base section is advantageously formed on the back support plate and this base section is at an angle relative to the back support plate. The moveable rack has a support section on which the base section of the back support plate lies. In this way, the weight of the blower unit can be taken up by the moveable rack in a simple manner. There are no additional attachment means necessary because the blower unit lies in place on the support section because of its own weight. At the same time, a simple removal of the blower unit from the moveable rack as well as a simple attachment of the blower unit thereto is possible.  
      The blower arrangement has a handle section for guiding the blower unit. In this way, the operator can comfortably guide the blower unit over the ground. A simple configuration of the moveable rack results when the moveable rack is bent from a tube and comprises essentially two L-shaped struts which are connected to each other at one end of their long legs by the handle section. The moveable rack can be made essentially from one bent tube section. The tube has low weight and sufficient stability. The moveable rack includes at least one wheel with which the blower unit can be guided over the ground. The two long legs are connected to each other via an axle on the opposite-lying ends on which at least one wheel, especially two wheels, is mounted. The axle functions simultaneously to reinforce the moveable rack. A conventional back-carried blower unit can be mounted in a simple manner on such a moveable rack and can be converted into a ground-guided blower unit in this way. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The invention will now be described with reference to the drawings wherein:  
       FIG. 1  is a side elevation view of the blower arrangement of the invention;  
       FIG. 2  is a side elevation view of the blower tube; and,  
       FIG. 3  is a rear elevation view of the blower arrangement viewed in the direction of arrow III in  FIG. 1 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION  
      The blower unit  1  shown in  FIG. 1  includes a housing  2  in which an internal combustion engine is mounted. The internal combustion engine is usually a two-stroke engine and drives a blower wheel which generates an air flow through a discharge pipe  4 . The discharge pipe  4  is configured as a short pipe-shaped stub and terminates at a small spacing above the ground  6 . The housing  2  of the blower unit  1  includes a back-carrier plate  7  which is configured as a separate component and is tightly connected to the housing  2 . A base section  15  is formed on the back-carrier plate  7  at the end of the plate facing toward the ground  6 . The base section  15  extends approximately perpendicularly to the back-carrier plate  7 . An operator-controlled unit  8  is provided for operating the blower arrangement  1   a  which includes a moveable rack  3 . The operator-controlled unit  8  includes a throttle lever  9  and a switch  10 . The switch  10  can be a selector switch for adjusting different modes of operation or a latch switch to prevent unintended actuation of the throttle lever  9 . The operator-controlled unit  8  is connected to a fuel metering device, especially a carburetor, via a Bowden cable  12 . The carburetor is mounted in the housing  2  and meters the air/fuel mixture to the engine.  
      The blower unit  1  is disposed on the moveable rack  3 . The moveable rack  3  has two wheels  5  with which the blower unit  1  can be guided over the ground. In lieu of the two wheels  5 , also one wheel or three or more wheels can be provided. Also, other means for guiding the blower unit over the ground can be provided, for example, a support device or the like which glides over the ground. The moveable rack  3  has a handle section  13  at which the operator can guide the moveable rack  3 . In the region of the wheels  5 , the moveable rack  3  also includes a support section  14  on which the base section  15  of the back-carrier plate  7  rests. The operator-controlled unit  8  includes a collar  11  with which the operator-controlled unit is releasably attached to the moveable rack  3 .  
      The operator-controlled unit  8  is in the normal operating position of the blower arrangement as shown in  FIG. 1  fastened above the back-carrier plate  7  and below the handle section  13  between the back-carrier plate  7  and the handle section  13  on the moveable rack  3 . The back-carrier plate  7  and the collar  11  are releasably attached to the moveable rack  3 . To convert the blower arrangement  1   a  into a blower unit  1 , which is carried on the back, the collar  11  and the back-carrier plate  7  are separated from the moveable rack  3 .  
      The blower arrangement  1   a  includes the blower tube  16  shown in  FIG. 2  for use when the blower unit  1  is carried on the back. The blower tube  16  can be fixedly attached to the discharge pipe  4  with a connecting piece  17 . The blower tube  16  includes a flexible segment  18  in a region next to the connecting piece  17 . The flexible segment can, for example, be configured as a bellows and connects to a rigid section  29 . On the rigid section  29 , a nozzle  19  is provided at the end facing away from the flexible segment  18 . The air flow from the blower tube  16  exits through the nozzle  19 . The operator-controlled unit  8  can be fixed with the collar  11  on the rigid section  29  as shown in  FIG. 2 .  
      The back-carrier plate  7  is strapped tightly to the back of the operator when the blower unit  1  is used as a back-supported blower unit. The flexible segment  18  functions to direct the air flow from the discharge pipe  4  around the body of the operator. The operator grasps the operator-controlled unit  8  with one hand and can, in this way, bring the nozzle  19  to the location of use as well as control the engine of the blower unit.  
      In  FIG. 3 , the blower arrangement  1   a  is shown with the moveable rack  3  in the direction of arrow III of  FIG. 1  directed toward the back-carrier plate  7 . The moveable rack  3  is built up of a bent tube and has two L-shaped struts  24 . The shorter legs of the struts  24  form the support section  14  of the moveable rack  3  shown in  FIG. 1 . The longer legs  25  extend approximately perpendicularly to the support section  14  and are connected to each other at their ends  26  by a handle section  13 . The ends  26  face away from the support section  14 . The two struts  24  run parallel to each other. The ends  27  of the struts  24  face away from the handle section  13  and face toward the support section  14 . At these ends  27 , the two struts  24  are connected to each other via an axle  20  on which wheels  5  are mounted at respective outer lying ends. The back-carrier plate  7  runs parallel to the two long legs  25  of the struts  24  and has a handle  28  on its end facing upwardly in the normal work position. The handle  28  is formed by a handle opening  22  in the back-carrier plate  7 . The two long legs  25  are connected to each other via a transverse strut  21  approximately at the elevation of the handle  28 . The handle  28  is connected to the transverse strut  21  by an attachment band  23 , for example, a VELCRO band. The transverse strut  21  is displaced relative to the handle  28  in the direction toward the support section  14  so that the attachment band  23  presses the base section  15  of the back-carrier plate  7  against the support section  14  of the moveable rack  3 . In this way, the blower unit  1  of the blower arrangement  1   a  is tightly and releasably connected to the moveable rack  3  via the attachment band  23 . By releasing the attachment band  23  and the collar  11  from the moveable rack  3 , the blower unit  1  can be released and utilized as a blower unit which can be carried on the back of an operator. The blower unit  1  is ready in this position after attachment of the blower tube  16  to the discharge pipe  4 .  
      In lieu of the moveable rack  3 , a different apparatus can be provided for guiding the blower unit  1  over the ground  6 . At least one wheel  5  can be mounted directly on the housing  2  of the blower unit  1 , for example, by insertion or clip-on of the wheel axle. In lieu of the wheels  5 , other means can be provided for guidance over the ground  6 . The operator guides the blower unit over the ground with the handle section. This handle section can be mounted directly on the housing, for example, it can be inserted or clipped thereto.  
      It is understood that the foregoing description is that of the preferred embodiments of the invention and that various changes and modifications may be made thereto without departing from the spirit and scope of the invention as defined in the appended claims.