Patent Publication Number: US-7213273-B2

Title: High pressure plunger

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the invention 
   The present invention relates to a high pressure plunger for use on drain, sink, and toilet, more particularly one, which is structured in such a way as to be suitable for use together with an air pump to get rid of a blockage with high-pressure air. 
   2. Brief Description of the Prior Art 
   A simplest conventional plunger includes a handle, and an inverted rubber bowl joined to a lower end of the handle. A blockage in a pipe is loosened, and got rid of by means of exerting suction and air pressure on the blockage repeatedly with the plunger. However, suction and air pressure producible with the plunger isn&#39;t very great, and it is possible that a blockage remains in a pipe after having been slightly moved with the plunger. 
   The inventor of the present invention taught an improvement on a plunger, and was granted U.S. Pat. No. 6,032,301 for making this improvement. The plunger includes an upper base, a pressure ball under the upper base, a correlative tubular shaft extending vertically through the pressure ball, a handle pivotally connected with an upper end of the correlative tubular shaft, a connecting rod connects to the correlative shaft, and a lower end stopper threadedly connected with the lower end of the connecting rod. The pressure ball can store air supplied by an air pump or compressor through an air inlet. The handle can be operated to move the correlative tubular shaft away from the upper opening of the connecting rod, thus letting the air stored in the pressure ball flow through the correlative shaft, the connecting rod and the lower end stopper into a clogged pipe or drain for clearing passage with a large force of pressured air. 
   However, because air stored in the pressure ball will travel a long distance through a narrow passage before it flows through the lower end stopper, and because the opening of the lower end stopper is small, the plunger still can&#39;t get rid of a blockage in a pipe or toilet effectively. 
   SUMMARY OF THE INVENTION 
   It is a main object of the invention to provide an improvement on a plunger to overcome the above-mentioned problem. The plunger of the invention includes a lever, a pipe, a rod passed through an axial hole of the pipe, a covering member, and a spring. The rod is joined to the lever such that it will be upwards displaced when the lever is pivoted upwards. The rod has a passage therein, and a head at an upper end for connection with an air pump. The covering member has a neck, and an outlet on a lower side. The pipe is inserted in the neck at a lower end. Two airtight rings are secured on an inner side of the neck. The rod is normally biased to a lowermost position by the spring. The lower end of the rod will block the outlet, and the passage will communicate with inside of the covering member when the rod is in the lowermost position. When the lever is pivoted upwards, high-pressure air will escape through the outlet of the covering member to push a blockage in a drain tube of a sink. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will be better understood by referring to the accompanying drawings, wherein: 
       FIG. 1  is an exploded perspective view of the first preferred embodiment of a plunger according to the present invention, 
       FIG. 2  is a vertical section of the first preferred embodiment, 
       FIG. 3  is a vertical section of the first embodiment being in use, 
       FIG. 4  is a vertical section of the second preferred embodiment, 
       FIG. 5  is a vertical section of the second embodiment being used, 
       FIG. 6  is a vertical section of the second embodiment equipped with another shape of rubber supplementary covering member. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring to  FIGS. 1 and 2 , a first preferred embodiment of a plunger in the present invention includes a supporting member  1 , a lever  2 , a pipe  3 , a connecting rod  4 , and a covering member  5 . 
   The lever  2  is positioned under, and pivoted to the supporting member  1 . The pipe  3  is passed through, and joined to the supporting member  1  at an upper end thereof. 
   The connecting rod  4  has a passage  41  therein, a cone-shaped tail end  45 , and a coupling head  42  joined to an upper end thereof for connection with an air pump. The passage  41  communicates with inside of the coupling head  42 , and it has an outlet portion, which is a certain distance from the cone-shaped tail end  45  of the connecting rod  4 . The connecting rod  4  is passed through an axial hole of the pipe  3  with the lower end thereof projecting out from a lower end of the pipe  3 , and it is connected to the lever  2  such that it will be upwards displaced relative to the pipe  3  when the lever  2  is pivoted upwards. 
   The covering member  5  has a holding room  51  therein, and it has a neck portion  52  on an upper side thereof, and an air outlet hole  54  on a lower side. The neck portion  52  has an axial hole in communication with the holding room  51 , and two airtight rings  53  secured on an inner side thereof. 
   In assembly, the covering member  5  is securely joined to the lower end of the pipe  3  at the neck portion  52  thereof, and the connecting rod  4  is passed through the neck portion  52 . And, a spring  44  is positioned around the connecting rod  4  in the holding room  51 , and a stopping ring  43  is secured around a portion of the connecting rod  4  that is between the outlet portion  45  of the passage  41  and the cone-shaped tail end  45 ; thus, the spring  44  can&#39;t fall off the connecting rod  4 , and the connecting rod  4  is normally biased to a lowermost position by means of the spring  44 ; when the connecting rod  4  is biased to the lowermost position, the cone-shaped tail end  45  will block the air outlet hole  54  of the covering member  5  to prevent air from traveling through the air outlet hole  54 , and the outlet portion of the passage  41  will be under both of the airtight rings  53 , allowing air to travel into the holding room  51  from the passage  41 . When the connecting rod  4  is displaced away from the lowermost position by means of pivoting the lever  2 , the outlet portion of the passage  41  will be between the airtight rings  53 , and air can&#39;t travel into the holding room  51  of the covering member  5  from the passage  41 . 
   To use the plunger, referring to  FIG. 3 , first an air pump is connected to the coupling head  42  of the connecting rod  4 , and the plunger is positioned such that the covering member  5  covers a plughole of a sink. Next, air is pumped into the holding room  51  of the covering member  5  through the passage  41  of the connecting rod  4  such that the holding room  51  contains high-pressure air. And, the lever  2  is pivoted upwards such that the connecting rod  4  moves away from the outlet hole  54  of the covering member  5 , and the cone-shaped tail end  45  no longer blocks the outlet hole  54 . Finally, the lever  2  is released so that the connecting rod  3  is displaced to the lowermost position by the spring  44 , and seals the outlet hole  54  again, and air is allowed to travel into the holding room  51  from the outlet portion of the passage  41  again. Thus, the high-pressure air in the holding room  51  travels through the plughole of the sink, and pushes a blockage formed in a drain tube connected to the plughole; the lever  1  is pivoted upwards and released repeatedly until the blockage is got rid of. 
   Referring to  FIGS. 4 and 5 , a second preferred embodiment of the invention includes a supporting member  1 , a lever  2 , a connecting rod  4 , and a covering member  5 . The lever  2  is positioned under, and pivoted to the supporting member  1 . The connecting rod  4  has a passage  41  therein, a cone-shaped tail end  45 , and a coupling head joined to an upper end thereof for connection with an air pump. The passage  41  communicates with inside of the coupling head, and it has an outlet portion, which is between upper and lower ends of the connecting rod  4 . The connecting rod  4  is connected to the lever  2  such that it will be upwards displaced when the lever  2  is pivoted upwards. The covering member  5  has a holding room therein, a through hole (not numbered) on an upper end, and an air outlet hole  54  on a lower end. Two airtight rings  53  are secured in the upper through hole of the covering member  5 . 
   In assembly, the connecting rod  4  is passed through the upper through hole of the covering member  5 , and a spring  44  is positioned around the connecting rod  4 , and a stopping ring  43  is secured around the connecting rod  4 , under the spring  44 ; thus, the spring  44  can&#39;t fall off the connecting rod  4 , and the connecting rod  4  is normally biased to a lowermost position by means of the spring  44  such that the cone-shaped tail end  45  blocks the air outlet hole  54  of the covering member  5 ; when the connecting rod  4  is biased to the lowermost position, the outlet portion of the passage  41  will be under both of the airtight rings  53 , allowing air to travel into the covering member  5  from the passage  41 . When the connecting rod  4  is displaced away from the lowermost position, the outlet portion of the passage  41  will be between the airtight rings  53 , and air can&#39;t travel into the covering member  5  from the passage  41 . Thus, the second preferred embodiment can be used in the same way as the first preferred embodiment to get rid of a blockage in a pipe. 
   Furthermore, the invention is equipped with a supplementary covering member  55 , which is made of rubber, and joined to the lower end of the covering member  5 , and which has several annular wall portions  551  on a lower side, such that when the plunger is used to get rid of a blockage in a pipe of a sink, there will certainly be an airtight joint between the plunger and the sink. 
   Referring to  FIG. 6 , another supplementary covering member  55 ′ is provided for use instead of the one  55 , which has a slightly different shape from the one  55 . 
   From the above description, it can be seen that according to the present invention, high pressure air is stored next to the outlet hole of the covering member, and will arrive at a blockage in a pipe rapidly after it is released, the drawback of the prior plunger as described in Background is overcome.