BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to an air blowgun, and more particularly to an innovated blowpipe mechanism of the air blowgun.  
           [0003]    2. Description of Prior Art  
           [0004]    In accordance with the conventional air blowgun  10  with a 4-inche standard length blowpipe, as shown in FIG. 1, it just only has a single function—blowing dust. Due to 80-psi pressure of discharge press, the conventional air blowgun  10  sprays wind-stream so fast that dust and debris will be rejected as blowing on them directly to occur shooting the operator or other people standing nearby dangerously, therefore this kind of over-concentrated high-speed spraying is just only used in site of necessary heavy blowing, so it is a shortcoming of the conventional blowgun.  
           [0005]    Because the conventional air blowgun employs a fixed blowpipe mechanism—the blowpipe is unable to be replaced, if operating in a narrow and deep site or meeting obstructer—can not extend the arm of the operator in the site, a long blowgun  20  has to be needed, as shown in FIG. 2, to the object, but the long blowgun  20  is difficult to work in a narrow short distance places, it hampers the wrist moving, so the user has to prepare long and short blowgun in the meantime for using in different working site. If the working site is a long distance in outside, the worker has to carry the different blowguns with him, it will bring him to inconvenience. This is another shortcoming of the conventional blowgun.  
           [0006]    When the conventional air gun with single function is used in other purposes, such as inflating tire to connect to different air gate, and pumping up a ball to connect to vent wire and so on, the individual adapting connectors must be needed, and mounted or removed from the tip of the blowgun as rapid as possible in order to replace another for meeting to other purpose, but the shortcoming of the individual connectors is too big volume, or too long length to occupy too much space to bring up inconvenience of carryover.  
         OBJECTS AND SUMMARY OF THE INVENTION  
         [0007]    It is therefore a main object of the present invention to provide an air blowgun having a connecting thread at the tip of the blowpipe for connecting different nozzles facilitating carryover and operation.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    [0008]FIG. 1 is a side view showing a conventional short blowgun.  
         [0009]    [0009]FIG. 2 is a side view of a conventional long blowgun.  
         [0010]    [0010]FIG. 3 is an exploded view showing attaching a nozzle having a screen of the present invention.  
         [0011]    [0011]FIG. 4 is a cross-section view showing the screen nozzle combined with the blowgun of the present invention.  
         [0012]    [0012]FIG. 5 is a scheme showing guard function of the screen nozzle of the present invention.  
         [0013]    [0013]FIG. 6 is a side view showing securing to a long blowpipe of the present invention.  
         [0014]    [0014]FIG. 7 is a side view showing the long blowgun working in a narrow and deep side to pick up a part with attraction of inside magnet of the present invention.  
         [0015]    [0015]FIG. 8 is an exploded view showing connecting to a charging adapter of the present invention.  
         [0016]    [0016]FIG. 9 is a cross-section view showing a combined charging adapter of the present invention.  
         [0017]    [0017]FIG. 10 is a cross-section view showing the working state of the charging adapter of the present invention.  
         [0018]    [0018]FIG. 11 is a solid view showing a plug-in inflating nozzle of the present invention.  
         [0019]    [0019]FIG. 12 is a cross-section view showing a plug-in inflating nozzle of the present invention.  
         [0020]    [0020]FIG. 13 is a solid view showing a low-pressure nozzle of the present invention.  
         [0021]    [0021]FIG. 14 is a side view of FIG. 13.  
         [0022]    [0022]FIG. 15 is a solid view showing a softy nozzle.  
         [0023]    [0023]FIG. 16 is a cross-section view of FIG. 15.  
         [0024]    [0024]FIG. 17 is a cross-section view showing working state of the softy nozzle.  
         [0025]    [0025]FIG. 18 is an exploded view showing connecting to a vent wire of the present invention.  
         [0026]    [0026]FIG. 19 is a cross-section view of FIG. 18.  
         [0027]    [0027]FIG. 20 is a cross-section view showing the working state of cooperating with the vent wire of the present invention.  
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0028]    Referring to FIG. 3 and FIG. 4, the present invention provides an air blowgun  30  comprising of a connecting thread  32  at the tip of the blowpipe  31  for connecting a screen nozzle  40 . Said screen nozzle  40  (as shown in FIG. 3 and FIG. 4) is comprised of a hollow main body  41  and a baffling key  42  contained in the hollow inside of the main body  41 . Said baffling key  42  is comprised of a threaded hole  421  at inside end for securing on the blowpipe  31  and leading compressed air in, and a magnet piece  423  embedded into the outside end, and a guide slot  422  crossing the both side and connecting with the threaded hole  421  for leading the compressed air into the inside of the main body  41  to form a ring wind-stream blowing out by the ring gap between the inside wall of the main body  41  and the baffling key  41 .  
         [0029]    Referring to FIG. 4, said screen nozzle  40  may guide the compressed air to spray out in a hollow thin cone, meanwhile by means of the diffused air film to carry out shielding function for prevent dust, water and oil and so on from reflecting to shoot the operator, further to improve the safety of operation, as shown in FIG. 5.  
         [0030]    On the other hand, said magnet piece  43  embedded into the tip end of the baffling key  42  makes the screen nozzle  40  have attraction function of attracting steel parts. This kind of screen nozzle  40  can be used in narrow and deep space or the finger unable to touch to places for picking up steel part by the magnet piece  43 .  
         [0031]    In accordance with above-described, due to employing the connecting thread  32  at the tip of the blowpipe  31 , the blowgun can secure with variety nozzle for meeting to different purposes.  
         [0032]    § Long and short blowgun conversion function:  
         [0033]    Referring to FIG. 6, securing an extending blowpipe  50  on the tip end of the blowgun  31  of the original short blowgun  30  is carried out said long blowgun conversion function for be used in narrow and deep space or hard touching place blocked by obstacles, and is converted so easily and simply. On the other hand, an extending blowpipe  50  is in convenience of carryover without the bother of carrying two conventional blowguns.  
         [0034]    § Magnet attraction function:  
         [0035]    Said magnet piece  43  embedded into the tip end of the screen nozzle  40  can pick up steel parts falling into a narrow and deep space hard touching place by arm. In general cases, the screen nozzle  40  secured on the short blowgun can deal with shallow space site, but with regarding to narrow and deep places, as shown in FIG. 7, the screen nozzle  40  is secured on the tip end of the long extending blowpipe  50  to pick up the steel parts easily and simply.  
         [0036]    § Inflating tire function:  
         [0037]    Referring to FIG. 8 and FIG. 9, securing an charging adapter  60  on the tip end of the blowpipe  31  can be used for inflating variety tires of wheels. Said charging adapter  60  includes a main-body  61  having a hollow stepped hole with a internal thread  611 , a push key  62  that has a stepped pin end with a both flat sides  621  thereon two side flow holes connecting to the back end hole, placed in the inside of the main-body  61 , rubber washers  64  for putting on the stepped pin carrying on sealing function, and a connector  63  having a hollow hole  631 , an outside thread at the front end for securing on the back end of the main-body  61 , and a back inside thread  632  for securing on the tip end of the blowpipe  31 .  
         [0038]    Referring to FIG. 10, when push said charging adapter  60  on the knockout pin  651  of the charging valve  65  of the tire so that the rubber washers  64  are pressed down to allow the compressed air give out from the side flow holes and via the vent hole  622  of the knockout pin  62  entering the inside of the tire to meet the necessary of inflating tire.  
         [0039]    § Plug-in pumping up function:  
         [0040]    Referring to FIG. 11 and FIG. 12, a plug-in charging connector  70  has an internal thread  71  at the back end for securing on the tip end of the blowpipe  31 , and a cone anti-slip plug-in charging connecting end for plugging into the charging valves of inflating ring, air bed or swimming ring and so on to pump it up directly.  
         [0041]    § Low-pressure nozzle function:  
         [0042]    Referring to FIG. 13 and FIG. 14, a low-pressure nozzle  80  securing on the tip end of the blowpipe  31  of the present invention has two inlets  81  at both sides absorbing outside air as the compressed air passing through to reduce the spraying pressure and to increase air flow of blowing and spreading area of spraying.  
         [0043]    § Soft nozzle function:  
         [0044]    Referring to FIG. 15 and FIG. 16, a soft nozzle  90  securing on the tip end of the blowpipe  31  provided by the present invention can protect the surface of metal or coated with layer without occurring sketching harm as touching against by the soft head. Referring to FIG. 17, when the cone soft head of the soft nozzle  90  is put into the inside of a pipe to blow out the dust at inside of the pipe, the soft nozzle  90  not only can seal the pipe, but also protect the interconnecting surface of the pipe, and join on or off rapidly and facilitating operating.  
         [0045]    § Vent wire inflating function:  
         [0046]    Referring to FIG. 18 and FIG. 19, a vent wire secured on the tip end of the blowpipe  31  provided by the present invention can inflate every kind of balls (as shown in FIG. 20) directly, wherein a main body  911  connects a needle valve  912  to the tip end of the blowpipe  31 . Said main body  91  provides a threaded end for securing on the tip end of the blowpipe  31 , and the another threaded end for securing in the needle valve  912 , and an escape orifice  913  formed on the proper side position for taking out the compressed air to avoid the danger of operation as the spraying hole of the needle valve is blocked.  
         [0047]    In accordance with above-described, the air blowgun provided by the present invention not only has all the functions of a conventional blowgun, but also by means of the connecting thread at the tip end of the blowpipe can be connected with variety nozzles to meet different necessaries in different working sites and purposes. The feathers of it are occupation small volume, mounting and replacing rapidly, facilitating operation, good practicability, and convenient for carryover, improving the professional function of the blowgun, meanwhile integrating multiple functions in one blowgun and saving a quite mount of money for equipping attachments for meeting to carry out other purposes. It has quite huge practicability and great value of industry.
The present invention relates to an air blowgun, and more particularly to an innovated blowpipe mechanism of the air blowgun, which can secure with variety nozzles individually for meeting to different purposes. Wherein a thread is set on the tip end of the blowpipe, thereby to connect with an extending long blowpipe, a screen nozzle, a charging adapter, a plug-in charging connector, a low-pressure nozzle, a soft nozzle, or a vent wire and so on to form multifunction tool, and it has small volume, easy mounting and replacing operation and facilitating carryover feathers.