Abstract:
A texture spray gun having an air passageway ( 29 ) and a texture material passageway ( 28 ) in a handle ( 14 ) of the gun do) and a selectively removable screw to convert the gun from a non-air bleed configuration to an air bleed configuration and an improved air valve ( 22 ) providing a minimum air flow regardless of the setting of the air valve ( 22 ), preventing texture material from clogging an air path at the outlet of the gun.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Application 60/804,528, filed Jun. 12, 2006, the entire contents of which are hereby expressly incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to a hand-held spray gun for spraying texture material on architectural surfaces such as ceilings and walls. The texture material is a semi-solid material in the form of a slurry which is typically applied using air in combination with the slurry to propel and disperse the slurry towards the surface to be coated. 
       BRIEF SUMMARY OF THE INVENTION 
       [0003]    This invention is an ergonomically designed spray gun to spray texture material and is convertible from a non-air bleed configuration to an air bleed configuration, provided that the air valve is set to provide some air flow. The conversion between non-bleed and air bleed is performed by removing a screw from the rear end of the spray gun main shaft which opens the center bore of the shaft to the air chamber within the spray gun body. With the screw removed and air being supplied to the spray gun, the spray gun will bleed air continuously through the air nozzle, regardless of the trigger location. With the screw in place and air being supplied to the spray gun, the gun will only bleed air when the trigger is actuated. In the first embodiment, an air valve may be used to control the flow of air from completely OFF to completely ON (open) air flow path. 
         [0004]    In a second embodiment, the air valve of the texture gun always bleeds a slight amount of air to prevent the texture material from clogging the gun when the trigger is depressed and the air valve is set to a “closed” or OFF position. The second embodiment will provide at least a small amount of air to the needle regardless of the position of the air valve. 
         [0005]    The invention also includes the aspect wherein the texture material flow path and the air flow path both are contained within the gun handle, resulting in a more ergonomic weight balance for the user. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0006]      FIG. 1  is a first perspective view from the right side and to the front of a texture gun useful in the practice of the present invention. 
           [0007]      FIG. 2  is a second perspective view from the left side and to the rear of the texture gun of  FIG. 1 . 
           [0008]      FIG. 3  is a third perspective view from the right side and to the rear of the texture gun of  FIG. 1 . 
           [0009]      FIG. 4  is a front elevation view of the texture gun of  FIG. 1 . 
           [0010]      FIG. 5  is a left side elevation view of the texture gun of  FIG. 1  showing a trigger in a released position in solid lines and a partially depressed condition in chain lines. 
           [0011]      FIG. 6  is a view similar to that of  FIG. 5 , except with the trigger in a fully depressed condition. 
           [0012]      FIG. 7  is a section view along line VII-VII of  FIG. 4 . 
           [0013]      FIG. 8  is an enlarged view of a front portion of the gun of  FIG. 7 . 
           [0014]      FIG. 9  is an enlarged view of a middle portion of the gun of  FIG. 7 . 
           [0015]      FIG. 10  is an enlarged view of a rear portion of the gun of  FIG. 7 . 
           [0016]      FIG. 11  is an enlarged view similar to that of  FIG. 10 , except with parts shown corresponding to the partially depressed trigger condition of  FIG. 5 . 
           [0017]      FIG. 12  is an enlarged view similar to that of  FIG. 10 , except with parts shown corresponding to the fully depressed trigger condition of  FIG. 6 . 
           [0018]      FIG. 13  is a view of the rear portion of the gun corresponding to that shown in  FIG. 10 , except with a screw removed for “bleeder” type operation. 
           [0019]      FIG. 14  is a section view taken along line XIV-XIV of  FIG. 5 . 
           [0020]      FIG. 15  is a first perspective view, similar to that of  FIG. 1 , except of an alternative embodiment of a texture gun useful in the practice of the present invention. 
           [0021]      FIG. 16  is a second perspective view, similar to that of  FIG. 2 , except of the texture gun of  FIG. 15 . 
           [0022]      FIG. 17  is a third perspective view, similar to that of  FIG. 3 , except of the texture gun of  FIG. 15 . 
           [0023]      FIG. 18  is a front elevation view of the texture gun of  FIG. 15 . 
           [0024]      FIG. 19  is a rear elevation view of the texture gun of  FIG. 15 . 
           [0025]      FIG. 20  is a bottom plan view of the texture gun of  FIG. 15 . 
           [0026]      FIG. 21  is a top plan view of the texture gun of  FIG. 15 , except with an air hose extension removed. 
           [0027]      FIG. 22  is a left side elevation view of the texture gun of  FIG. 15  showing the trigger in a released position. 
           [0028]      FIG. 23  is a section view of the texture gun of  FIG. 15 , taken along line XXIII-XXIII of  FIG. 18 . 
           [0029]      FIG. 24  is a key to  FIGS. 25 and 26 . 
           [0030]      FIG. 25  is an enlarged view of a front portion of the gun of  FIG. 23 . 
           [0031]      FIG. 26  is an enlarged view of a rear portion of the gun of  FIG. 23 . 
           [0032]      FIG. 27  is a still further enlarged view of detail XXVII of  FIG. 26 . 
       
    
    
     DETAILED DESCRIPTION  
       [0033]    Referring now to the Figures, and most particularly to  FIGS. 1-14 , a first embodiment of the texture gun of the present invention may be seen. The spray gun of the present invention may be set up as a non-air bleed configuration or an air bleed configuration. In a non-air bleed (or “non-bleeder”) configuration, air used to propel the texture mixture is turned at least substantially all the way OFF when the gun is not triggered, i.e., when the trigger is not pulled by a user to discharge texture material. In an air bleed (or “bleeder”) substantial air flow continuously exits the front of the gun at the texture nozzle regardless of the position or activation of the trigger; in such a configuration, air is continuously ON at the level used to propel texture material, whether the texture material is being discharged or not. In other words, in the non-bleeder configuration, the trigger turns ON both the air flow and texture material flow. In the bleeder configuration, air flow is always ON, and the trigger turns ON only texture material flow. 
         [0034]    Regardless of the air flow configuration to which the spray gun is set up, the texture material supplied to the spray gun will not be released until the spray gun main shaft travels at least 0.090″. If the spray gun is configured to be non-bleed, air will bleed through the air nozzle of the spray gun immediately upon trigger actuation and will be joined by texture material only after the main shaft has traveled at least 0.090″. Material flow is controlled by degree of trigger actuation which controls how far the main shaft travels towards the rear of the spray gun. As the shaft travels rearward, material flow increases. The material flow adjustment knob on the rear of the spray gun body limits the trigger movement and shaft travel from minimum to maximum with continuously adjustable settings in between. When the desired flow adjustment is achieved, the knob can be locked in place to prevent accidental movement of the adjustment knob. 
         [0035]    Air flow can also be controlled within the spray gun body via the rotation of the air flow control valve which is located perpendicular to the air passage port within the spray gun handle. Rotation of the valve knob either increases or decreases the flow of air from full “on” to either: i) full “off” (in the first embodiment) or to ii) a “minimum” air flow (in the second embodiment) with continuously adjustable settings in between. The air flow control valve knob is attached to an air valve shaft which perpendicularly intersects the main air passage port. At the point of intersection is a hole in the air valve shaft, which, based on the rotation of the knob, exposes the hole in varying degrees to the air passage port of the spray gun, thus controlling the air flow through the gun head to the air nozzle. In this aspect of the present invention, an integrated air valve is provided on the texture spray gun, unlike typical prior art texture spray guns. 
         [0036]    The spray gun handle houses both the material and air flow passage ports unlike prior art texture spray guns which typically have (at most) only the air passage port running through the handle while the material passage port is (typically) forward of the gun trigger. With the material passage forward of the spray gun trigger, the user must “fight” the weight of the material hose, filled with texture material, because it is cantilevered out away from the user&#39;s hand, thus increasing hand and arm strain. 
         [0037]    This strain is reduced in the practice of the present invention where the material passage runs through the ergonomically designed spray gun handle which is grasped in the palm of a user during operation. 
         [0038]    Referring to the Figures, and most particularly to  FIGS. 1-5 , the gun  10  has a gun body  12  preferably formed of aluminum. Gun body  12  has a handle  14  and a trigger  16 . A nozzle nut  18  is threadably secured to the front of the gun body  12  and retains a texture nozzle  20  to the gun body  12 . An air valve  22  is located in gun body  12 . The air valve has an air valve knob  24  on an air valve shaft  26 , aspects of which may be seen in  FIGS. 7 and 14 . 
         [0039]    Referring now also to  FIGS. 6 and 7 , more details of the texture nozzle  20  and other parts of the gun  10  may be seen. Gun  10  has a texture material passageway or port  28  and an air passageway or port  29 . Texture port  28  may be connected via a texture hose  30  to a supply of texture material (not shown), and air port  29  may be connected via an air hose  32  to a source of compressed air (not shown). 
         [0040]    Referring now also to  FIGS. 8 ,  9 , and  10  various details of the texture gun  10  may be seen. Gun  10  has an air nozzle  34  threaded to a front end of a texture shaft  36 . Texture shaft is sealed to gun body  12  via an energized or non-energized U cup seal  38  which is retained by a retainer screw threaded into gun body  12 . A trigger attachment  42  couples motion of the trigger  16  to an air trip rod  44  when the trigger is pulled or depressed. O-rings  46 ,  48  and  50  seal the parts against which they are positioned within the gun. A shut off valve  52  is threaded onto the air trip rod  44 . Shut off valve  52  has diametral apertures  54  in fluid communication with air port  29 . Air port  29  is sealed by a plug  55 . An air valve seal  56  is threaded onto a rear portion of the texture shaft  36 . The air valve seal  56  has an external cone shaped surface  58  which mates with to seal against an internal cone shaped surface  60  serving as an air valve seat  62  formed on the shut off valve  52 . A screw  64  closes an end of the air valve seat portion of the shut off valve  52 . A first spring is located between the air valve seal  56  and the air valve seat portion  62  of the shut off valve  52  and provides a separating force between these two parts when the trigger  16  is depressed, moving the air trip rod  44  and shut off valve  52  rearwardly. A second spring  68  acts against the texture adjustment knob  70  and urges the shut off valve  52  closed when the trigger  16  is released. The air nozzle  34  acts as a mechanical barrier to prevent the flow of texture material from the texture passageway  28  to the texture nozzle  20  when the trigger  16  is released, as shown in  FIG. 8 . Texture adjustment knob  70  may be threaded in or out of the gun body  12  to set the maximum opening for the texture material path or port  28  by limiting the maximum rearward travel of the texture shaft  36  in response to an operator pulling the trigger  16 . The setting of knob  70  (and the consequent maximum flow of texture material) may be locked by tightening a texture knob lock nut  78  against the gun body  12 . It is to be understood that a shoulder  80  on the shut off valve  52  will contact a forward face  82  of the knob  70  to limit rearward travel of the texture shaft  36 , as may be seen most clearly with these features  80  and  82  separated in  FIG. 10  (material flow OFF) and in contact in  FIG. 12  (material flow full ON). 
         [0041]    With the trigger  16  released, both the texture port  28  and the air port  29  are shut off (provided screw  64  is installed). Referring now to  FIGS. 5 and 11 , when the trigger  16  is moved from the position shown in solid lines in  FIG. 5 , to the position shown in chain (dash dot) lines, the shut off valve  52  is opened, allowing air to flow as indicated by arrows  72  in  FIG. 11 . It is to be understood that air will continue to flow as the trigger is fully depressed, as shown in  FIG. 6 , at which time texture material will be allowed to flow (as indicated in  FIG. 12  by arrows  74 ), because the air nozzle is retracted from the texture nozzle. 
         [0042]    The above operation describes the gun  10  in a non-bleeder type operation where the air is bled only when the trigger is depressed. Gun  10  can be converted to a full time bleeder operation by removing screw  64 , after which air will flow as indicated by arrows regardless of whether the trigger  16  is pulled or not. In this aspect of the present invention, gun  10  is thus seen to be easily convertible between non-bleeder and bleeder operation by the presence or absence of screw  64 , once the texture adjustment knob is removed, giving access to the screw  64 . 
         [0043]    Referring now to  FIG. 14 , a section view of the gun  10  along line XIV-XIV of  FIG. 5  may be seen. This view illustrates certain aspects of the air flow indicated by arrows  84  through the air passageway  29  and through a main transverse passage  86  in the shaft  26  of the air valve  22 , with the valve in a fully open condition, corresponding to that shown in  FIG. 11 . The air valve  22  may be used to control the flow of air used to propel the texture material by partially closing the air passageway  29  using the knob  24  to rotate shaft  26  to partially or fully block passageway  29 . 
         [0044]    Referring now to  FIGS. 15-27 , the texture gun may be seen in a second embodiment  110 . In this embodiment, the same or similar parts and features are identified by the same reference numerals, except multiplied by  10  from the reference numerals associated with the first embodiment described supra. Additional or different parts or features have reference numerals in the new series without necessarily having corresponding reference numerals associated with the first embodiment. 
         [0045]    In  FIGS. 15-22 , various external views of the texture gun  100  may be seen. Texture gun  100  has a gun body  120  and handle  140 , each of which may be the same as for the gun  10 . Texture gun  100  has a trigger  160  that differs from trigger  16  in that trigger  160  has an upper portion  162  formed at an angle  164  (see  FIG. 22 ) to a lower portion  166 , in contrast to the trigger  10  which is formed with a straight gripping section. The angle  164  may be 12 degrees to improve the ergonomics of the trigger  160 , making it easier and more comfortable for a user to grasp. Trigger  160 , like trigger  16  is connected to the gun by a pivot  161  and has a pivot radius  163 . The distal section  166  of the trigger  160  forms a first angle  168  with respect to the pivot radius  163 , while the proximal section  162  forms a second angle which is the difference between angles  162  and  164  with respect to the pivot radius  163 . The first angle  168  may be about 44 degrees, while the second angle may be about 32 degrees. 
         [0046]    Gun  100  also has a nozzle nut  180  to retain a nozzle  200  and an air valve  220 . Gun  110  also has an air valve knob  240  and a texture adjustment knob  700 , along with a texture knob lock nut  780 . Gun  100  also has a texture material passageway  280  and an air passageway  290 . Referring now also to  FIG. 23 , gun  100  has an air valve shaft  260  similar to shaft  26  and a plug  550  to close the top end of the air passageway  290 . 
         [0047]    Referring now to  FIGS. 25 and 26 , gun  100  has an air nozzle  340  mounted on a texture shaft  360 , and a U-cup seal  380  to prevent leakage along the shaft  360  and retainer screw  400  to hold the seal  380  in position as the shaft moves axially during operation of the gun  100 . Gun  100  also has a trigger attachment  420 , an air trip rod  440 , and three O-rings,  460 ,  480  and  500  to seal against air leakage. Pulling trigger  160  will move the trigger attachment  420  rearward, moving the air trip rod  440  rearward by a distance of at least 0.090 inches until contact is made between the air trip rod  440  and an air valve seal member  560 . As the air trip rod  440  moves back and before contact is made with the air valve seal  560 , an air valve seat  620  is moved rearward, separating internal cone shaped surface  600  on the air valve seat  620  from the external cone shaped surface  580  on the air valve seal  560 . This separation opens the air flow path from air passageway  290  to the air nozzle  340 . Once contact is made between the air trip rod  440  and the air valve seal  560  and rearward motion continues, the texture shaft  360  will be moved rearward, separating the air nozzle from the texture nozzle  200  and allowing texture material to flow from the texture material passageway  280  out through the texture nozzle, as propelled by the air exiting a central bore  342  in air nozzle  340 . 
         [0048]    As in the first embodiment, a screw  640  may be removed to convert gun  100  to “bleeder” operation in which air flows continuously from air passageway  290  through the air nozzle bore  342 , regardless of the position of the trigger  160  and air valve seal  560 . Spring  660  operates to ensure separation of the cone shaped surfaces  580  and  600  when the trigger is moved rearward moving the air trip rod  440  into engagement with the air valve seal  560 . Spring  680  biases the various air and texture parts to a closed position when the trigger  160  is released, shutting off the flow of texture material from passageway  280 . 
         [0049]    Unlike the first embodiment, air flow cannot be completely blocked in gun  100  since there is a secondary transverse passage  862  in addition to a primary transverse passage  820  in shaft  26 , which may be seen most clearly in  FIG. 27 . Two positions are shown for the shaft in  FIG. 27 . The solid lines show a full ON position wherein full airflow is permitted through passageway  860  from air passageway  290 . The dashed lines show a minimum air flow condition wherein only a small amount of air is permitted to flow through secondary passageway  862  from air passageway  290 . As stated above, the minimum air flow prevents texture material from entering the bore  342  when the knob  240  is turned to the lowest air flow setting. 
         [0050]    The invention is not to be taken as limited to all the details thereof as modifications and variations thereof may be made without departing from the spirit or scope of the invention. For example and not by way of limitation, the minimum air flow feature may be provided by a rotational stop on the shaft of the air valve to limit movement to prevent fully closing the primary or main transverse passage, as an alternative to having a secondary passage in the air valve shaft.