Abstract:
There is disclosed a portable fan for drying floor surfaces, comprising a fan casing and a receiver attached to a rearward outside surface of the fan casing for receiving and storing first and second parallel, telescoping struts of a collapsible handle within first and second parallel wells disposed therewithin; and a collapsible handle having first and second parallel, telescoping struts stored in the first and second wells of the receiver and extendable by pulling upon the collapsible handle or upon release of a latch operated by a button in a handle grip connected between upper ends of the first and second struts of the collapsible handle. In another embodiment, a fixed carrying handle is disposed on a top side of the fan casing and a clearance recess is provided in the underside of the fan casing for receiving the fixed carrying handle of a first portable fan therein when a second portable fan having the clearance recess is stacked on top of the first portable fan having the fixed carrying handle, for transport or storage of the first and second portable fans.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention generally relates to portable electric fans and, more particularly, to portable electric fans adapted to circulating air or drying surfaces within interior spaces.  
         [0003]     2. Description of the Prior Art  
         [0004]     Portable electric fans or blowers such as so-called carpet dryers are well-known in the art. Fans of this type are often used in a wide variety of building environments. Frequently, multiple fans are required to accomplish the necessary air circulation or drying operations. Typical applications include drying an interior space damaged by leakage or ingress of water into the space or drying large carpeted areas following a steam cleaning or shampooing operation. In such applications, fans or blowers may be of the centrifugal or axial type and typically have wheels and/or handles enabling them to be easily moved about. For example, U.S. Pat. No. 5,265,895 issued to Barrett, for a “Floor Fan Handtruck Apparatus and Method,” is directed to a centrifugal fan having a housing or casing and a horizontal air outlet, a pair of wheels attached to the casing and a fixed, elongated handle extends upward along the rear of the casing from a point between the pair of wheels, for moving the fan like a two-wheeled hand truck. The fan casing also includes a carrying handle attached to the top of the casing. The cord is stored on a hook attached to the elongated handle. In another example, U.S. Des. Pat. No. D484,586 issued to Intravatola, for the ornamental design of a “Blower,” an axial electric fan is supported by a frame structure that has a pair of wheels attached to a lower part of the frame.  
         [0005]     Portable fans typically have one of several kinds of handles to facilitate portability. However, the fixed-length handle taught by Barrett is limited in its utility because the fan cannot readily be used in a crawl space where the elevation is less than about four feet, a common application situation. Further, Barrett&#39;s fan is not adaptable to stacking, one on top of the other, for transporting  1 - or maneuvering a pair of fans. Moreover, the fan of Intravatola likewise is not adaptable to stacking or for transporting a pair of fans as a compact assembly for ease of maneuvering.  
         [0006]     In another field of art, U.S. Pat. No. 2,693,001 issued to Vance, for a “Cord Support For Suction Cleaners,” is directed to a cylindrical-bodied vacuum cleaner having a collapsible “T”-shaped handle that slides in a track along one side of the vacuum cleaner body between a retracted position and an extended position. The cord is supported by a pair of opposing hooks, one fixed to the side of the vacuum cleaner over one end of the track near an upper end of the body and the other hook attached to the lower end of the vertical bar of the “T”-shaped handle. In the retracted position, the opposing hooks retain the cord coiled there-around in a stored position. As the “T”-shaped handle is released from its retracted position and extended, the hook at the lower end of the “T”-shaped handle moves toward the upper hook, reducing the distance between the opposing hooks, thereby releasing the cord from storage. The “T”-shaped handle, when extended may also be used  14  to maneuver the vacuum cleaner about on a pair of wheels attached to the lower end of the body of the vacuum cleaner. However, the “T”-shaped handle, having only a single shaft, is prone to twisting and a loss of control when maneuvering the vacuum cleaner because the handle does not resist the torque imparted thereto while steering the vacuum around an obstacle. Moreover, the vacuum cleaner of Vance is not usable as a fan for circulating air or drying large interior spaces and is also not adapted to stacking or for transporting a pair of devices stacked together.  
         [0007]     None of the known prior art portable electric fans or blowers have a torque-resistant, collapsible handle that stores out of the way and, when extended, is readily adapted to transporting or maneuvering stacked fans. Moreover, none of the known fans or blowers disclosed above are adapted to stacking during storage or for transporting a plurality of fans as a compact assembly for ease of maneuvering. What is needed is an electric fan or blower that includes a collapsible handle, is adapted for easily maneuvering in use or in storage, and that enables at least two such fans to be stacked for transport or storage. Such a handle must be sturdy, resistant to torque effects during maneuvering, and easily adjusted, retracted and extended. The fan should be configured for secure stacking of at least two units without additional components or accessories.  
       SUMMARY OF THE INVENTION  
       [0008]     Accordingly, there is disclosed a portable fan for drying floor surfaces, comprising a fan casing that encloses a rotating fan blade assembly powered by an electric motor operating from power supplied via a power cord; a receiver attached to a rearward outside surface of the fan casing for receiving and storing first and second parallel, telescoping struts of a collapsible handle within first and second parallel wells disposed therewithin, the receiver having a length dimension and an upper end and a lower end of the length dimension; and a collapsible handle having first and second parallel, telescoping struts stored in the first and second wells of the receiver and extendable to a length of at least approximately twice the length of the receiver from the upper end of the receiver upon release of a latch operated by a button in a handle grip connected between upper ends of the first and second struts.  
         [0009]     In another embodiment, a fixed carrying handle is disposed in a central location on a top side of the fan casing; and a clearance recess in an underside of the fan casing is provided for receiving the fixed carrying handle of a first portable fan therein when a second portable fan having the clearance recess is stacked on top of the first portable fan having the fixed carrying handle, for transport or storage of the first and second portable fans together.  
         [0010]     In another embodiment, first and second wheels are attached to opposite ends of an axle supported by the lower end of the receiver for convenient transport and maneuvering of the fan. The wheels are positioned such that an underside of the fan casing is supported a predetermined distance above a floor surface during operation of the portable fan. First and second feet attached to the underside of the fan casing at respective corners of the fan casing diagonally opposite from each first and second wheel, wherein the first and second feet cooperate with the first and second wheels to support the fan casing a predetermined distance above the floor surface.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]      FIG. 1  illustrates a front side perspective view of one embodiment of a portable fan having a collapsible handle, shown extended, according to the present disclosure;  
         [0012]      FIG. 2  illustrates a rear side perspective view of the portable fan of  FIG. 1  having a collapsible handle, shown extended, according to the present disclosure;  
         [0013]      FIG. 3A  illustrates a side profile view of the portable fan of  FIG. 1  having a centrifugal type of fan and the collapsible handle, shown retracted, according to the present disclosure;  
         [0014]      FIG. 3B  illustrates a side profile view of an alternate embodiment of the portable fan of  FIG. 1  having an axial type of fan and the collapsible handle, shown retracted, according to the present disclosure;  
         [0015]      FIG. 4  illustrates a rear profile view of the portable fan of  FIG. 1 , the wheels and the collapsible handle, shown retracted, according to the present disclosure;  
         [0016]      FIG. 5  illustrates a bottom side view of the portable fan of  FIG. 1 , including the wheels and the clearance recess formed in the bottom of the casing to accommodate the carrying handle of a like portable fan as in  FIG. 1 , when the units are stacked one above the other; and  
         [0017]      FIG. 6  illustrates a side view of two portable fans according to the present disclosure, one stacked on top of the other as enabled by features of the invention and shown being transported by a worker to a destination.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0018]      FIG. 1  illustrates a front side perspective view of one embodiment of a portable fan having a collapsible handle, shown extended, according to the present disclosure. The portable fan  10 , configured as a centrifugal fan in this view, includes a fan casing  12  that encloses the fan blade and motor assembly (not shown) within a cylindrical, drum-like container. Air is drawn into both ends of the drum-like container, i.e., both sides  28  of the fan casing  12 , and expelled centrifugally, i.e., tangentially with respect to the squirrel cage rotor (not shown in  FIG. 1 ) spinning within the fan casing  12 , from the air outlet  24 . Protruding from a rear side of the fan casing  12  is a stage  16  to which is attached a receiver  14 . The receiver  14  provides for the storage and support of a collapsible handle  18  that includes telescoping strut members  19 ,  21 , which may be collapsed within the wells  23  in the receiver  14  by pressing downward on a handle grip  20  connected between upper ends of the telescoping strut members  19 . The collapsible handle  18  may be extended into an intermediate or extended position by pulling upon the handle to the desired position. The telescoping struts may be held in any of various predetermined positions by detents (not shown) placed in strategic positions along the telescoping mechanism. Such detents may be spring loaded. Thus, the handle  18  may be retained in a retracted or collapsed, intermediate, or extended position. An operator may override the detent tension merely by moving the collapsible handle  18 , i.e., by pulling or pushing upon the collapsible handle  18 .  
         [0019]     Alternatively, a button  22  may be provided in the handle grip  20  for releasing a latch mechanism (not shown) in the collapsible handle  18  to enable the retraction or collapse of the collapsible handle  18 . The collapsible handle  18  maybe configured by an internal spring mechanism to self-extend or retract upon activation of the latch. The receiver  14  for storing the collapsible handle  18  is oriented vertically and disposed as far to the rearward as is practicable to facilitate the stacking of like fans and to orient the collapsible handle in a comfortable position for transport and maneuvering. When the handle is extended, the space between the telescoping struts  19 ,  21  may be adapted for supporting a warning sign or advertising placard. For example, the corners of such a sign or placard may be attached to fasteners (not shown) which clamp on or otherwise attach, to the adjacent first or second telescoping strut, and are readily detachable therefrom, preferably without the use of tools.  
         [0020]     Continuing with  FIG. 1 , incoming air enters the fan casing  12  through a grill  30  (and a grill  31  on the opposite side of the fan casing  12  as shown in  FIG. 2 ) that may be mounted in both sides  28  of the fan casing  12 . The grills  30 , 31  allow a maximum unimpeded flow of air, prevent the entry of light-weight debris into the fan casing  12 , and provide a safety feature preventing contact with the blades when the fan is being operated. Air movement produced by the fan blade within the fan casing  12  is expelled via a vent  26 . The vent  26  may include slat members disposed across the air outlet  24  to direct and smooth the air flow. The vent  26  is further configured such that a minimum of obstruction to the flow is provided through openings small enough to limit access by a child&#39;s hand, for example. The fan casing  12  may also include a carrying handle  32  on an upper portion of the fan casing  12 , positioned so that the handle  32  is directly above the center of mass of the portable fan  10 . A cord storage device  34 , which may be first and second cord storage hooks mounted in an opposing relationship or the single, molded structure shown in the figure, is used to support a coiled power cord  36  against the upper portion of the fan casing  12 .  
         [0021]     In the preferred embodiment, the fan casing  12  may be fabricated as a rotomolded high density polyethylene plastic structure. Other materials and fabrication processes are, of course feasible as will be apparent to persons skilled in the art. For example, the method of fabrication may alternatively employ a blow molding process. Polyethylene of high, medium, or low density may be fabricated by either rotomolding or the blow molding process. In yet another alternative embodiment, an injection molding process maybe used wherein the fan casing is formed from ABS or PVC material.  
         [0022]     In operation, the portable fan  10  is typically positioned to direct air for drying in a horizontal direction, approximately parallel to the floor. A bail mechanism (not shown) may be attached to the bottom of the fan casing  12  to raise the air outlet vent  24  slightly so that the expelled air stream is directed at an angle relative to the floor surface.  
         [0023]      FIG. 2  illustrates a rear side perspective view of the portable fan  10  of  FIG. 1  having a collapsible handle  18 , shown extended, according to the present disclosure. The view of  FIG. 2  is similar to  FIG. 1  except that the portable fan  10  has been rotated  180  degrees to show the rear side of the portable fan  10 . Accordingly, the structural features of  FIG. 2  are similar to those illustrated in  FIG. 1  and bear the same reference numbers, with the addition of wheels  40  attached to an axle  42  installed through a lower portion of the receiver  14 . Also shown in  FIGS. 1 and 2  are brackets  52  and  53  for supporting the assembly of the rotor  50  and the motor/shaft  54 , as will be further described in conjunction with  FIG. 3 .  
         [0024]      FIG. 3A  illustrates a side profile view of the portable fan of  FIG. 1  configured as a centrifugal fan having a squirrel-cage type of fan blade and the collapsible handle  18 , shown retracted within the wells  23 , according to the present disclosure. The grill  30  has been removed from the side of the fan casing  12  in this view so that the fan blade and motor assembly may be seen. A foot  46  is attached to the near side of the underside of the air outlet  24  of the fan casing  12 . A second foot (not shown) is located on the other side of the fan casing  12  and is thus not visible in this view. Shown in phantom is the outline of a clearance recess  48  disposed in the bottom of the fan casing  12 . As will be described herein below in conjunction with  FIG. 6 , the clearance recess  48  provides space to receive the carrying handle  32  of a second portable fan  10  when two or more such fans according to the present disclosure are stacked vertically, one above the other.  
         [0025]     A squirrel cage fan blade or rotor  50  is shown within the fan casing  12 . The drum-like rotor  50 , which typically contains a large number of blade elements disposed uniformly around the circumference of the rotor, is supported by and spins on a shaft driven by an electric motor  54 , shown in phantom. The assembly of the rotor  50  and the motor  54  (including the motor shaft, not shown) may be supported by the three-spoked bracket  52  attached within the air inlet openings  28  of each side of the fan casing  12 . Wiring for the motor  54  is connected to the power cord  36  at a terminal box  56 , which may also include, for example, an ON/OFF switch (not shown), a speed control (not shown), and/or a thermal circuit breaker or fuse (not shown). All other structures shown in  FIG. 3A  are the same as shown in  FIGS. 1 and 2  and bear the same reference numbers.  
         [0026]      FIG. 3B  illustrates a side profile view of a possible alternate embodiment of the portable fan of  FIG. 1 , configured as an axial fan having a propeller type of fan blade, and the collapsible handle  18 , shown retracted within the wells  23 , according to the present disclosure. As in  FIG. 3A , the grill  30  has been removed from the side  28  of the fan casing  12  in this view so that the fan blade  60  and motor  54  (shown in phantom) may be seen. This embodiment is very similar to the centrifugal fan embodiment of  FIG. 3A  except that the fan blade  60  is a propeller-type of blade (having three blades in this view), which directs the air outward from the side (facing out of the page) of the fan casing  12  along the axis of the fan blades  60 . The air inlet (not shown) for the axial fan is on the opposite side (not shown) of the fan casing  12 . The portable fan of  FIG. 3B  thus does not have the tangential or centrifugal air outlet  24  of  FIG. 3A . Although not as quiet running as the centrifugal fan for the same volume of air in cubic feet-per-minute, the propeller-type fan blade of the axial fan is typically less costly to manufacture because of its fewer blade elements. The feet  46  are moved to a position closer to the wheels  40 . In all other respects, the portable fan  10  of  FIG. 3B  is substantially identical with the portable fan of  FIG. 3A , with the same structures bearing the same reference numbers.  
         [0027]     In the embodiments described and illustrated herein above, an AC powered electric motor  54  is shown for driving the fan  50 ,  60  (See  FIGS. 3A and 3B ). It is also possible to drive the fans  50 ,  60  with DC electric motors from batteries, fuel cells or solar energy conversion devices, or with other types of motors. For example, an internal combustion engine operating on gasoline, liquid (propane) or compressed natural gas as a fuel may be used in some applications. Further, it is even possible to operate the fan  50 ,  60  with an external combustion engine such as a steam engine fired by burning any of a variety of available fuels. Engines such as these may be more suited to larger fans or fans that would be deployed in situations where noise is a secondary consideration to the power required to deliver the required volume of air.  
         [0028]      FIG. 4  illustrates a rear profile view of the portable fan of  FIG. 1 , the wheels  40  and the collapsible handle  18 , shown retracted within the wells  23 , according to the present disclosure. Shown in this view are the fan casing  12 , and the receiver  14  attached to the stage  16 , which protrudes from the rear side of the fan casing  12 . The wheels  40  are supported on axle  42 , which is installed in the lower end of the receiver  14 . A pair of feet  44  are attached to the upper corners of the receiver  14 . The handle grip  20 , including the release button  22  is shown just above the receiver  14 , the collapsible handle  18  (not shown) being fully retracted within the receiver  14 . A portion of the carrying handle  32  is shown on the top of the fan casing  12 .  
         [0029]      FIG. 5  illustrates a bottom side view of the portable fan of  FIG. 1 , oriented with the air outlet  24  facing upward on the page. The wheels  40  and the clearance recess  48  formed in the bottom of the fan casing  12  (see also  FIGS. 3A and 3B ) is also visible. The clearance recess  48  is provided to accommodate the carrying handle  32  of a like portable fan  10  as in  FIG. 1  when the units are stacked one above the other. Also shown in  FIG. 5  is a view of the bottom end of the receiver  14  attached to the stage  16 , which is attached to the fan casing  12 . The feet  46  shown in  FIG. 3A  are shown attached to the bottom of the fan casing  12  at each of the forward corners thereof.  
         [0030]      FIG. 6  illustrates a simplified side view of two portable fans according to the present disclosure, one stacked on top of the other as enabled by the features of the invention described herein above and shown being transported by a worker  98  to a destination along a floor  100 . The lower of the two portable fans, portable fan  70  is shown having a clearance recess  72  and a carrying handle  74  as indicated in phantom. The receiver  76  of portable fan  70  is attached to the casing of the fan  70  by the stage  94 . The collapsible handle  78  of the fan  70  is shown fully extended from the receiver  76 . The portable fan  70  is shown tilted backward, being held by the operator  98  grasping the handle grip  96 , the fan  70  resting on the wheels  90  installed on the receiver  76 . The wheels are disposed to roll along the floor  100 . A second portable fan  80 , identical with the lower fan  70 , is shown stacked on top of the lower fan  70 . The carrying handle of the lower fan  70  fits within the clearance recess  82  in the bottom of the casing  12  of the second fan  80 . The second fan  80  also has a receiver  86 . The collapsible handle  88  of the second fan  80  is fully retracted within the receiver  86 . The wheels  92  of the second fan  80  straddle the stage  94  of the lower fan  70 . The receiver  86  of the second fan  80  rests against the extended collapsible handle  78  of the lower fan  70 . In this way a pair of portable fans  10  constructed according to the present disclosure may be stacked for ease of maneuvering or transporting from one place to another by one person. Moreover, it is understood from  FIG. 6  that a third fan of like construction (not shown) may be stacked upon the top of the second fan  80  if it is necessary to move three such fans to one location. Further, in a storage location more than three such fans may be stacked because of the configuration of the casing according to the present invention.  
         [0031]     While the invention has been shown in only one of its forms, it is not thus limited but is susceptible to various changes and modifications without departing from the spirit thereof.