Abstract:
A PU foam rubber fluid applicator includes a handle, the handle having a receptacle adapted to accommodate a PU foam rubber can, a nozzle connected to the valve tube of the loaded PU foam rubber can, a lever pivoted to the receptacle and supported on a return spring and controlled by one finger of the user&#39;s hand holding the handle to lift the nozzle and to further open the valve tube of the PU foam rubber can, and a retaining block pivoted to the receptacle and forced by a spring member to lock the PU foam rubber can.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a PU foam rubber fluid applicator for the application of a PU foam rubber fluid and, more particularly, to a laborsaving PU foam rubber fluid applicator. 
     2. Description of the Related Art 
     When applying PU foam rubber fluid from a PU foam rubber can to fill up the gaps between the door/window and the wall, gaps between the air conditioner and the wall, or the internal space of a door, plywood, or any of a variety of building materials, a PU foam rubber fluid applicator may be used.  FIG. 1  shows a PU foam rubber fluid applicator according to the prior art. As illustrated, the PU foam rubber fluid applicator comprises a nozzle  200 , the nozzle  200  having a top inner thread  201  for threading onto the outer thread  101  of the valve tube  102  of a PU foam rubber can  100 , and two pressure members  202  provided at two sides of the nozzle  200 . When in use, the loaded PU foam rubber can  100  is turned upside down, and then compress the pressure members  202  with both hands to force the valve tube  102 , thereby causing the PU foam rubber fluid to flow out of the PU foam rubber can  100 . This design of PU foam rubber fluid applicator is not satisfactory in function. Operating this structure of PU foam rubber fluid applicator requires much effort. When applying PU foam rubber fluid to a high place above the operator&#39;s head, the user may be unstable to compress the pressure members  202  stably and evenly. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished under the circumstances in view. 
     It is the main object of the present invention to provide a PU foam rubber fluid applicator, which can conveniently be operated with one single hand to apply PU foam rubber fluid to any accessible places. 
     It is another object of the present invention to provide a PU foam rubber fluid applicator, which can easily be operated with less effort. 
     To achieve these and other objects of the present invention, the PU foam rubber fluid applicator is comprised of a handle, a retaining block, a nozzle, and a lever. The handle has one end terminating in a receptacle adapted to accommodate a PU foam rubber can. The nozzle is connected to the valve tube of the PU foam rubber can. The lever is pivoted to a bottom rod of the receptacle and supported on a return spring and controlled by one finger of the user&#39;s hand holding the handle to lift the nozzle and to further open the valve tube of the PU foam rubber can, and a retaining block pivoted to the receptacle and forced by a spring member to lock the PU foam rubber can. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of a PU foam rubber fluid applicator according to the prior art. 
         FIG. 2  is an exploded view of a PU foam rubber fluid applicator according to the present invention. 
         FIG. 3  is an exploded view in an enlarged scale of one part of the PU foam rubber fluid applicator according to the present invention. 
         FIG. 4  is an exploded view in an enlarged scale of another part of the PU foam rubber fluid applicator according to the present invention. 
         FIG. 5  is a sectional assembly view of the PU foam rubber fluid applicator according to the present invention. 
         FIG. 6  is a sectional view in an enlarged scale of a part of the PU foam rubber fluid applicator according to the present invention (retaining block, receptacle, and PU foam rubber can). 
         FIG. 7  is a sectional view in an enlarged scale of another part of the PU foam rubber fluid applicator according to the present invention (bottom rod of receptacle, lever, and nozzle). 
         FIG. 8  is an elevational assembly view of the PU foam rubber fluid applicator according to the present invention (retaining block, receptacle, and PU foam rubber can). 
         FIG. 9  is a schematic sectional view showing the operation of the PU foam rubber fluid applicator. 
         FIG. 10  is similar to  FIG. 7  but showing the nozzle lifted, the valve tube of the PU foam rubber can opened. 
         FIG. 11  is similar to  FIG. 6  but showing the retaining block moved to the unlocking position. 
         FIG. 12  is an elevational view of a part of an alternate form of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 2˜4 , a PU foam rubber fluid applicator A for PU foam rubber injector is shown comprised of a handle  10 , a retaining block  20 , a nozzle  30 , a lever  40 , a first torsional spring  50 , and a second torsional spring  60 . 
     The handle  10  has one end terminating in a receptacle  12 . The receptacle  12  comprises a receiving open chamber  11 , an inside annular flange  13  (see  FIG. 5 ) disposed in the receiving open chamber  11 , a bottom opening  14  at the center of the bottom side in fluid communication with the receiving open chamber  11  (see  FIG. 4 ), a pair of parallel lugs  15  provided at the periphery, a through hole  16  through the peripheral between the lugs  15  in fluid communication with the receiving open chamber  11 , a narrow groove  17  upwardly extended from the through hole  16 , and a bottom rod  18  downwardly extended from the periphery at one side. The bottom rod  18  has a bottom end terminating in a transverse barrel  181  and a protruded portion  182  at one end of the transverse barrel  181 . 
     The retaining block  20  has a stop flange  21  longitudinally disposed at one side, and a hooked portion  22  at one end. 
     The nozzle  30  has an inner thread  31  at the top end, and two push rods  32  aligned at two sides. 
     The lever  40  comprises two barrels  41  arranged in parallel at one end, a recessed portion  42  disposed in one end at the bottom side between the barrels  41  (see  FIG. 4 ), a through hole  43  disposed adjacent to the recessed portion  42 , and a locating block  45  transversely disposed at the top side on the middle. The locating block  45  has a top notch  44 . 
     The assembly process of the PU foam rubber fluid applicator A is outlined hereinafter. The PU foam rubber can  70  is set in the receiving open chamber  11  of the receptacle  12  to rest the flange  73  of the PU foam rubber can  70  on the inside annular flange  13  of the receptacle  12  (see  FIG. 5 ), letting the valve tube  72  of the PU foam rubber can  70  extend out of the bottom opening  14  of the receptacle  12 , and then the inner thread  31  of the nozzle  30  is threaded onto the outer thread  71  of the valve tube  72 , and then the retaining block  20  and the first torsional spring  50  are put in between the lugs  15  and pivotally connected thereto with a first pivot S 1 , keeping the two opposite ends of the first torsional spring  50  respectively stopped at the stop flange  21  and the narrow groove  17  and letting the hooked portion  22  of the retaining block  20  pass through the through hole  16  and hook on the flange  73  of the PU foam rubber can  70  (see  FIG. 6 ) to prevent falling of the PU foam rubber can  70  out of the receiving open chamber  11  of the receptacle  12 , and then the through hole  43  of the lever  40  is coupled to the nozzle  30  for enabling the push rods  32  to be stopped at the top side of the lever  40 , and then the second torsional spring  60  and the barrels  41  of the lever  40  are pivotally coupled to the barrel  181  of the bottom rod  18  of the receptacle  12  with a second pivot  52 , keeping the two opposite ends of the second torsional spring  60  respectively stopped at the inner side of the protruded portion  182  and the recessed portion  42  of the lever  40  (see  FIG. 7 ). When assembled, as shown in  FIG. 8 , the second torsional spring  60  imparts an upward pressure to the lever  40 , thereby causing the lever to be stopped against the push rods  32 . 
     When in use, attach a delivery tube  33  to the bottom end of the nozzle  30  (see  FIG. 8 ), and then hold the handle  10  with the hand and pull the lever  40  with one finger (see  FIG. 9 ) to push the push rods  32  upwards and to further force the nozzle  30  upwardly against the valve tube  72  of the PU foam rubber can  70  (see  FIG. 10 ), thereby causing the valve tube  72  to be opened, for enabling the contained PU foam rubber fluid to pass out of the valve tube  72  to the delivery tube  33  via the nozzle  30  (see  FIGS. 8 and 10 ). When released the hand from the lever  40 , the second torsional spring  60  immediately returns the lever  40 , and at the same time the valve tube  72  moves downwards from the open position to the close position by means of the spring power of its internal spring means (the structure of the valve tube  72  is of the known design and not within the scope of the claims of the present invention, no further detailed description in this regard is necessary). When the contained PU foam rubber fluid used up, press one end of the retaining block  20  to conquer the spring force of the first torsional spring  50 , causing the retaining block  20  to turn about the first pivot S 1  in one direction and to further disengage the hooked portion  22  from the flange  73  of the PU foam rubber cab  70  (see  FIG. 11 ), and then rotate the PU foam rubber can  70  to disengage the outer thread  71  of the valve tube  72  from the inner thread  31  of the nozzle  30 , for enabling the PU foam rubber can  70  to be taken out of the receiving open chamber  11  of the receptacle  12  for a replacement. 
     Further, an anti-slip cap  19  may be capped on the top side of the handle  10  for positive gripping of the hand (see  FIGS. 8 and 9 ). The nozzle  30  may be variously shaped.  FIG. 12  shows the use of an alternate form of the nozzle  30 . As illustrated in  FIG. 12 , the push rods  32  of the nozzle  30  are respectively stopped at the notch  44  of the locating block  45  and an inside wall of the lever  40 . This alternate form achieves the same effect. 
     The receptacle  12  further comprises a screw hole  111  disposed in communication with the receiving open chamber  11  (see  FIG. 2 ) for receiving a tightening up screw  80 . The threaded shank  81  of the tightening up screw  80  is threaded into the screw hole  111  and stopped against the periphery of the PU foam rubber can  70  to hold the PU foam rubber can  70  in position (see  FIGS. 5 and 9 ). A C-shaped retainer may be fastened to the threaded shank  81  of the tightening up screw  80 , preventing the tightening up screw  80  from falling out of the receptacle  12 . When wishing to replace the PU foam rubber can  70 , the tightening up screw  80  must be loosened. 
     As indicated above, after loading of a PU foam rubber can  70 , the user can conveniently apply the contained PU foam rubber fluid to fill up gaps between the door/window and the wall, gaps between the air conditioner and the wall, or the internal space of a door, plywood, or any of a variety of building materials. When applying the contained PU foam rubber fluid, the user needs only to hold the handle  10  with the hand and then to pull the lever  40  with one finger to further lift the nozzle  30  and the valve tube  72  of the PU foam rubber can  70 . 
     Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention.