Patent Publication Number: US-6702203-B2

Title: Dual spray gun for painting and cleaning

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a dual spray gun for painting and cleaning, and more particularly, to a dual spray gun that combines tin and pipe sucking methods into one set that can be used separately and independently or in a series connection so as to improve the painting or cleaning operation. 
     2. Description of the Prior Art 
     In accordance with a conventional dual spray gun for painting and cleaning used for painting priming paint or cleaning various work-pieces, whether sucking up paint or cleaner, most of the dual spray guns can be divided into a tin dual spray gun  11 , as shown in FIG. 1, and a pipe dual spray gun  12 , as shown in FIG. 2, for suiting different working environments. 
     For example, the tin dual spray gun  11  carries less paint or cleaner and is used in smaller working area painting or cleaning for a shorter working period, but it has shortcomings just like heavier units that limit wrist and hand dexterity making the wrist tire easily and working period shorter. 
     The pipe dual spray gun  12  with a long pipe  121  can use a large tank  13  at the other end of the pipe  121 , supplying more paint or cleaner to be sucked up and sprayed out for meeting the necessity of larger working areas. Meanwhile, the working radius is increased due to the pipe  121 . The pipe dual spray gun  12 , by the larger tank  13  providing more paint or cleaner, overcomes the shortcoming of interruption of the liquid in the tin, instead supplying enough liquid so that a larger working area can be processed and a larger working radius is achieved by means of the longer pipe  121 . 
     Although it has so many merits, there are some demerits obviously existing. For example, because the worker has to move often for adjusting position during working, sometimes he or she forgets the length limit of the pipe  121  when moving and overruns the length of the pipe  121  so that the pipe  121  is withdrawn out from the surface of the liquid in the tank and interrupts the spraying process unexpectedly affecting the quality of painting and delay work. On the other hand, the tank  13  is easily overturned by dragging the pipe  121  or by being run into by a passing worker casually to cause the paint or cleaner liquid to run out, so the operator has to pay attention to the positions of the tank  13  and the pipe  121  all the time, distracting his attention and further affecting job quality. 
     The above-mentioned tin and pipe spray guns are designed professionally to work independently. If the user has to use both methods on a job, he or she would buy the two kinds of dual spray guns for painting and cleaning because they can not be used convertibly or alternatively. Therefore, the cost must be higher and the operation is inconvenienced. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     It is therefore a main object of the present invention to provide a combined tin and pipe dual spray gun for painting and cleaning, which can be used convertibly and alternatively in tin style and pipe style with low cost and improved operation. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a conventional tin dual spray gun; 
     FIG. 2 is a side view of a conventional pipe dual spray gun; 
     FIG. 3 is an exploded view of the present invention; 
     FIG. 4 is a cross-sectional view of the present invention; 
     FIG. 5 is a cross-sectional view showing the pipe method of the present invention; and 
     FIG. 6 is a cross-sectional view showing the tin method of the present invention. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring to FIG.  3  and FIG. 4, the present invention is comprised of a three-way T-shaped main body  21  having an inlet tap hole  211  for securing to an air blowgun  30  via a combined bolt  22  and a locating nut  221 , a front tap hole  212  for securing a blow head  23 , a downward sucking tap hole  214  connecting to the front tap hole  212 , and a through-hole  213  connecting the front tap hole  212  and the sucking tap hole  214  to the inlet tap hole  211  for locating an atomized nozzle  24  from the inlet tap hole  211  side so that a tip end of the nozzle  24  stretches inside the front tap hole  212  and above the sucking tap hole  214 . The sucking tap hole  214  is used for securing on a pipe connection  51  at one end of a pipe  50 . 
     A filter connection  52 , holding a filter leaf  521  for filtering foreign matter, is on the other end of the pipe  50 . An internal screw  522  is built on the inside of the filter connection  52  for securing on a bolt  411  with a through-hole on a cap  41  of a tank  40  that is sealed with an O-ring  42 . The bolt  411  with the through-hole built on a top side of the cap  41  also can be secured on the sucking tap hole  214  of the T-shaped main body  21 . The cap  41  has a sucking tube  43  extending at a bottom side connecting to the through-hole of the bolt  411  for sucking up the paint or cleaner contained in the tank  40 . The cap  41  also has a pair of pivoting holes  412  for a C-shaped handle  413  for carrying. 
     The above-mentioned mechanism of the combined tin and pipe dual spray gun provided by the present invention can be used as an individual tin spray gun or as an independent pipe spray gun, or as a combined tin and pipe dual spray gun, as follows: 
     4. Used in a combined tin and pipe method: 
     Referring to FIG.  3  and FIG. 4, the T-shaped main body  21  connects to the pipe connection  51  of the pipe  50  the same way as above-described. The other end of the pipe  50 , via the filter connection  52 , connects to the cap  41  of the tank  40  to construct a combined longer pipe and tank dual spray gun. Because the tank  40  not only can be put in a proper position, but also carried with the user moving to the working site, the working radius can be increased at will. Meanwhile, it not only overcomes the demerit of the conventional tin dual spray gun, like being heavy, but also has the merit of the conventional pipe dual spray gun, as being light and being a longer working radius. 
     Due to adopting screwing connections between the tank  40  and the pipe  50 , even if the tank  40  is overturned by dragging the pipe  50 , the sealed tank  40  still can keep the liquid inside without running out, and with moving of the tank  40 , the working radius can be increased infinitely. The tank  40  not only can be put on the ground, but also hung at different heights above the ground according to the necessity of the working environment. Besides, the operator can carry the tank  40  with one hand, while the other hand can hold the spray gun  30  so that processing becomes more rapid and more facilitated. 
     5. Used in a pipe method: 
     Referring to FIG. 5, the filter connection  52  on the tip end of the pipe  50  can be used independently, thereby not only filtering foreign matter with the filter leaf  521  held inside of the filter connection  52 , but also being in the painting tank  60  directly, whether small or big, working as the conventional pipe spray gun. In painting, the filter connection  52  can be put into a variety of painting tanks, and in cleaning, the cleaner tank can be used directly by putting it on the filter connection  52  end of the pipe  50 . 
     6. Used in a tin method: 
     Referring to FIG. 6, the tank  40  can be secured on the T-shaped main body  21  to construct a tin dual spray gun for painting and cleaning, like the conventional one, it can be selected depending on necessity of the working environment. 
     Therefore, according to the above-described, we find that the present invention has the following merits: 
     1. Used in the combined tin and pipe method makes the working radius extend infinitely in a painting or cleaning process. Meanwhile the tank not only can be set at different heights, but also can be carried and according to the necessity of the working environment, it can be moved or placed at will, so it has higher mobility and facility, without any worry of spilling caused by overturning. 
     2. Combining the tank and the T-shaped main body to form an individual spray gun for use in a smaller working area and a high mobility site. 
     3. For suiting to a large working area and long working period of the working environment, the present invention can be joined into a pipe dual spray gun by securing the pipe on the T-shaped main body. 
     So the present invention can suit any working environment by changing the combination style, in any of three ways.