Abstract:
A manually operable spray gun which provides a variable spray pattern of liquid passing through the gun from a source of pressurized liquid. A valve spool is reciprocally movable in opposite directions by a pivotally mounted trigger. One spool end has a valve which closes flow through the spool; the other spool end is a flow control element having a flow control surface. The spool can be moved from a position where the valve controlling the flow into the spool is closed to a position where the valve is open and the spacing between the flow control element and the nozzle is varied. By varying this spacing, liquid flow can be varied from flowing directly to a nozzle orifice to flowing along the interior conical surface of the nozzle. The diameter of the conical pattern may be varied by changing the spacing between the flow control element and the nozzle.

Description:
[0001]    Priority is claimed to U.S. Provisional Application No. 61/571,244, filed Jun. 23, 2011, which is herein incorporated by reference. 
     
    
       [0002]    The present invention relates to spray guns and particularly spray guns which provide a variable spray pattern. 
         [0003]    Manually spray guns heretofore utilize a rotatable nozzle in order to vary the spray pattern there from. See for example, U.S. Pat. No. 5,183,322, issued Feb. 2, 1993 to James Haruch. Other spray guns have used manually actuable trigger levers. See for example, U.S. Pat. No. 4,541,568, issued Sep. 17, 1985 to William Lichfield. 
         [0004]    Adjustable nozzles have a drawback in that spraying liquid may contact the hands of the user. Many times such liquids are toxic, and such hand contact is not desired. It is also desirable to provide a variable spray pattern using a trigger lever in a manually gripable handle. However, the control of the spray from a shutoff to a pattern which may either be a stream, or a conical pattern of variable diameter has not been achievable in lever operated spray guns. In other words, ergonometric considerations respecting spray guns are that the spray guns control the spraying action by being capable of shutting of flow, i.e., stopping the spray, and readily selecting the spray pattern whether the pattern desired is a stream, a conical spray pattern or a spray pattern including both stream and conical patterns. 
         [0005]    Accordingly, it is the principal object of the present invention to provide an improved spray gun which is trigger actuable and also be operated manually. 
         [0006]    Is it a further object of the invention to provide a trigger lever operated spray gun having a selectable spray pattern which may be a pattern in the form of a stream or patterns of conical shape of desired diameter which conical patterns may include a stream. 
         [0007]    Briefly described, a manually operated spray gun embodying the invention includes a handle through which flow from a pressurized liquid source may pass into a bore. Within the bore, a spool is reciprocally movable by a trigger lever pivotally mounted in the handle. The extent through which the lever is pivoted controls the flow from shutoff (closed or sealed off) to a stream and then to a conically pattern of desired diameter. The spool has a valve at an input end thereof and a flow control element at an output end thereof. The flow control element cooperates with a nozzle. The nozzle has an orifice through which a stream may pass and also has a conical internal surface through which flow from around the outside of the flow control element is guided into a conical pattern. The pivotal motion and extent of pivoting of the lever may be controlled by a mechanism which limits the pivotal motion so that the desired pattern can be obtained. This mechanism may constitute a cam surface which follows by a portion of the lever and is prevented, by virtue of the cam diameter from moving beyond the desired pivotal distance. 
         [0008]    The present invention also embodies a spray gun having a chamber having at one end there of an orifice and a conical surface which narrows to the orifice (such as provided by a nozzle), and a spool or tubular member having a rotational axis which is movable longitudinally along such axis within chamber towards and away from the conical surface in which the axis is aligned with the orifice and the conical surface of the chamber. The tubular member having a passageway for inlet of pressurized fluid through the passageway, and a surface enabling flow of pressurized fluid from the passageway in a conical path toward the conical surface of the chamber, such that movement of the surface of the tubular member towards or away from said orifice adjusts the shape of pressurized fluid exiting the spray gun through the orifice. 
     
    
     
         [0009]    The foregoing and other objects, features and advantages of the invention will become more apparent from a reading of the following description in connection with the accompanying drawings wherein: 
           [0010]      FIG. 1  is perspective view of a spray gun embodying the invention; 
           [0011]      FIG. 2  is a perspective exploded view showing the parts of the spray gun illustrated in  FIG. 1 ; 
           [0012]      FIG. 3  is top view of the spray gun shown in  FIG. 1 ; 
           [0013]      FIG. 4  is a front view from the side of the spray gun shown in  FIG. 1 ; 
           [0014]      FIG. 4A  is a front view from the side of the spray gun, but with a control mechanism positioned to obtain a stream spray pattern; 
           [0015]      FIG. 5  is a sectional view of the spray gun taken along the line  5 - 5  of  FIG. 3  where flow through the spray gun is closed; 
           [0016]      FIG. 6  is an enlarged view showing the mechanism for controlling the flow through the spray gun using a trigger lever as well as a cam for controlling the distance through which the trigger lever may rotate; 
           [0017]      FIGS. 7 ,  8 , and  9  are views similar to  FIGS. 3 ,  5 , and  6 , respectively, which show the spray gun in a position to provide a liquid stream through a nozzle at the output end of the spray gun; 
           [0018]      FIGS. 10 ,  11 , and  12  are views similar to  FIGS. 3 ,  5 , and  6 , respectively, showing the spray gun position to provide an adjustable conical spray pattern; 
           [0019]      FIG. 13  is a sectional view along the line  13 - 13  of  FIG. 4 , which illustrates a mechanism for controlling the distance through which the trigger lever can pivot so as to obtain either shutoff or a spray pattern which varies from a stream to a conical pattern of selected diameter; and 
           [0020]      FIG. 13A  is a section view taken along the line  13 A- 13 A of  FIG. 4A . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0021]    Referring first to  FIGS. 1-3 , there is shown a spray gun  10  having a handle  12 . The handle  12  is made up of a grip portion  14  adapted to be grasped by the palm of the hand of the operator, and a body portion  16  extending there from. A nozzle  18  is attached, such as by screwing, into the front end of body portion  16 . A pivotal lever providing a trigger  20  is mounted on a pin  56  extending front skirt portion  22  of the body portion  16 . The trigger  20  has indentations at the front thereof for facilitating grasping of the trigger by the fingers of the hand of the operator whose palm engages grip portion  14 . A manually rotatable mechanism  23  is rotational mounted in skirt  22  of the body portion  16 . The manually rotatable mechanism  23  is described in more detail below to as trigger pivot rotation control mechanism. 
         [0022]    As shown in  FIG. 2 , a hose coupling  24  is secured, such as welded, to the bottom of grip portion  14  of handle  12  and a hose (not shown) is attachable to coupling  24  and engages barbs along the length of the coupling  24 . Such hose on coupling  24  is preferably with a sleeve having slots which are secured by means of a spring latch  26 . The design of the hose coupling, and a sleeve which provides a nut secured to the end of the hose, is shown in U.S. Pat. No. 5,931,508, issued Aug. 3, 1999 to Clark F. Spriegel, which is incorporated herein by reference. 
         [0023]    The design of the spray gun  12  has ornamental features which are the subject matter of a design patent application in the name of the inventors hereof filed concurrently herewith. This ornamental design is characterized at least by an array of slots and ridges on grip portion  14  of handle  12 . 
         [0024]    The components of the spray gun  10  is shown in  FIG. 2  and the assembly thereof is shown in  FIGS. 5 ,  6 ,  8 ,  9 ,  11  and  12 . These components include a spool  30  which is movable within a bore or chamber  32  of the body portion  16 , as shown in example  FIG. 5 . The spool  30  is movable between a nozzle  18  which is fixed in position once screwed into the front end of the body portion  16 . Unlike the prior art, the nozzle  18  preferably is not rotatable to set the spray gun to a desired spray. 
         [0025]    Spool  30  has flanges  36  and  38 , which are rings attached to the spool  30  and spaced from each other. One of these rings  38  captures a spring  40 . The rear end of the spool  30  captures an O-ring  42 . Another O-ring  44  is captured in a groove  46  on the periphery of the spool  30 . A plug  47  is screwed into the a threaded rear end of the spool  30  and closes a liquid passage in the form of a bore  106  extending through spool  30 . This bore  106  communicates with one of radial slots, openings, or inlet ports  49 , such as shown for example in  FIGS. 2 and 5 . There may be a plurality of slots, for e.g.,  4 , spaced 90 degrees apart from either other near the rear end of spool  30 . 
         [0026]    A flow control element  48  is part of the spool  30  and disposed at the front end thereof. A slot  50  behind the flow control element  48  receives another O-ring  52 . Slots or outlet ports  54  spaced periphery around the front end of the spool  30  behind the flow control element  48  provide for liquid passage through the bore  106  of spool  30 . 
         [0027]    Trigger lever  20  is pivotally mounted on a pin  56  extending through skirt  22  of the body portion  16 . This pin  56  extends through holes  58  in the two sides of the skirt and is fixed to the skirt. The pin  56  extends through a hole  60  through the upper end of the trigger lever  20 . There is a semicircular indentation  62  at the top of the trigger lever so as to provide clearance for trigger lever  20  to pivot about pin  56  without interference with spool  30 . 
         [0028]    A projection  64  near the upper end of the trigger lever  20  is engagable with a cam shaft  66  of a trigger pivot rotation control mechanism  23 . This cam shaft  66  is integrated with a disc  68  having a tab or rib  70  which is engagable by the fingers of the operator to rotate the cam shaft  66  (see also  FIGS. 13 and 13A ). Another disc  72  having an opening  76  with a flat  78  along one side thereof engages the end  74  of the cam shaft  66  to align the cam shaft with disc  72  when the cam shaft passes through openings  90  in skirt  22  (see  FIG. 2 ). The end  74  of cam shaft  66  may have snap-in connection provided by dimples and indentations on the cam shaft and the surface of an opening  76 . This connection enables the cam shaft  66  to snap into one of disc  68  and be rotationally mounted in the skirt  22  of body portion  16 . The disc  72  has a finger engagable tab or rib  80  similar to tab or rib  70  to facilitate rotation of cam shaft  66 . 
         [0029]    As shown in  FIG. 2 , flow control element  48  has a plurality of slots  84  in a surface thereof which cooperates with nozzle  18  so as to provide for a circular flow path for pressurized liquid leaving the exit port slots  54 . These slots  54  provide radially oriented, as opposed to linear flow, to the nozzle  18  so as to facilitate the formation of a conical spray pattern. 
         [0030]    As shown in  FIG. 5 , nozzle  18  has an internal conical surface  86  with an orifice  88  at the apex thereof. This is the orifice through which flow of the liquid passes responsive to pivot of trigger  20 . Either stream or conical flow patterns as may be selected by manual rotation of discs  68  and  72 , which provides two knobs  28  graspable via tab  70  and/or  80 , respectively. Spool  30  may be considered a tubular member having a rotational axis which is movable along such axis within chamber  32  towards and away from nozzle  18  at one end of chamber  32 , in which such axis is aligned with orifice  88  and the geometric axis of conical surface  86 . 
         [0031]    The hose (not shown in  FIG. 5 ) communicates with a liquid passageway  100  through handle  12 . The liquid flows through handle grip portion  14  into the bore of the body portion  16  where it encounters a valve  102  at the end of the spool  30 . This valve is defined by  0 -ring  42  and an inclined circular surface  104  which is part of the bore  32  through body portion  16 . Valve  102  is shown closed in  FIGS. 5 and 6 . Thus flow is inhibited through inlet ports  49  and the passage  106  through the spool  30 . The valve  102  at the rear end of spool  30  thereof seals the flow of fluid into the passage  106  through outlet ports  54 . The bore  106  in spool  30  is also sealed by the  0 -ring  44  so that flow is restricted through passage  106  when the valve  102  in opened. 
         [0032]    The cam shaft  66  is positions so as to allow the trigger lever  20  to pivot in a counter-clockwise direction as shown in  FIGS. 5 and 6  about pivot pin  56 . Spring  40  which bears against the rear end of the nozzle  18  biases spool  30  away form nozzle  18  so that the valve  102  closes passage into bore  106  of spool  30 . Spraying from the spray gun  30  is then inhibited. 
         [0033]    The location of the part of the spray gun  10  is also shown in the top view of  FIG. 3 . It will be observed that the tabs  70  and  80  of the trigger pivot rotation control mechanism  23  are in a general horizontal position when the ability of the spray gun  10  to spray liquid is inhibited by stopping flow of pressurized liquid from handle passage  100  through valve  102  into the passage  106  of spool.  FIG. 7  illustrates the trigger pivot rotation control mechanism  23  where tabs ribs  70  and  80  are in a generally vertical position. Then the cam shaft  66  is arrange so that trigger  20  may be pivoted forward away from handle grip portion  14  or clockwise in order to open the valve  102  at rear end of spool  30 . In this position as shown in  FIGS. 7 ,  8 , and  9 , spray gun  10  provides a spray pattern in the form of a stream. 
         [0034]    Movement of trigger  20  to the position for urging the spool  30  by engagement of trigger  20  with flange ring  36  is limited by cam shaft  66 . The spool  30  is moved towards nozzle  18 , as shown in  FIGS. 8 and 9 , against the bias of the spring  40  to a position where the control surfaces  110  of the flow control element  48  ( FIG. 9 ) are spaced a sufficient distance from conical surface  86  of nozzle  18  to permit linear flow of the pressurized liquid through the handle passage  100 , the inlet ports  49 , and the passage  106  to the spool  30 . The flow passes radially through the outlet ports  54  of the spool and then flows linearly along the interior conical surface  86  of the nozzle to the orifice  88 , where it exits as a liquid stream. In other words, the spacing of the surface of the flow control element  48  from the nozzle surface  86 , that is between the head of spool  30  provided by element  48  and the nozzle  86 , allows free flow of the liquid stream and ensures that a liquid stream is outputted from the orifice  88  of the nozzle  18 . 
         [0035]    Referring to  FIGS. 10 ,  11 , and  12 , to provide a conical spray pattern from spray gun  10  tabs  70  and  80  of the trigger rotation control mechanism  23  are turned toward the right or in the direction to enable the cam shaft  66  to present its maximum diameter to the cam follower  64  of the trigger  20 . The surface of the cam shaft  66  may be ratcheted so as select different amount of rotation, each rotation defines a different diameter of the conical spray pattern, from a full diameter when the spacing of the conical interior surface  86  of the nozzle  18  is less than the spacing when the spray is to be in the form of a stream, as described in connection with  FIGS. 7 ,  8 , and  9 . Then the flow through flow control end is via slots  54  along the slots  84  of the head of spool  30  defining the flow control element  48  in conjunction with interior conical surface  86  of nozzle  18  to generate an arcuate flow. This arcuate flow of liquid extends through the orifice  88  and out of the orifice in the form of a conical flow pattern. The distance between the flow control element  48  (or head of spool  30 ) may be changed to control the diameter of the conical spray pattern. In other words, the absence of a gap (or very small gap) between the flow control element  48  the spool head and the nozzle internal conical surface  84  provides a specific geometry which forces the liquid to rotate to create the conical spray pattern. 
         [0036]    Referring now to  FIGS. 4 and 13 , there is shown a position of the trigger pivot rotation control mechanism  23  where the tabs  70  and  80  are vertical so as to provide for the stream pattern.  FIGS. 4A and 13A  show the trigger pivot rotation control mechanism  23  positioned with the tabs  70  and  80  generally horizontal so as to provide for sealing or shutoff to inhibit flow. The cam shaft  66  is shown in snap in relationship with the disc  68  of the right hand side of the control mechanism, as shown in  FIGS. 13 and 13A . The cam surface controls the amount of rotation or pivotal movement of the handle so as to obtain the position of the spool  33  for either shut off or stream operation in  FIGS. 4 and 4A , respectively. In either case, the cam follower  64  bears against the cam shaft  66  so as to limit the pivot rotation of the trigger  20  to obtain the desired flow pattern. 
         [0037]    In summary of spray gun  10  operation, with application of pressurized fluid to handle passage  100 , the trigger pivot rotation control mechanism  23  can rotate the cam shaft  66  to present different diameter stopping surfaces with respect to trigger projection  64 , thereby adjusting the forward-most pivot positional extent of the trigger  20  to first, second, and third positions as graphically depicted on the body portion  16  as a circle, dash, and three radial dashes, respectively, which are alignable to tabs  70  and/or  80  by rotation of discs  68  and  72 , respectively. At the first position, trigger  20  is set to a forward-most rotational position so that when trigger is pivoted backwards such enables shut-off to a stream and then a conical spray of low to high diameter, and then vise versa in the opposite pivot direction (see  FIGS. 3 ,  5 , and  6 ). At the second position, trigger  20  is set to a forward-most rotational position so that a stream exits spray gun  10 , and then if desired further backward pivoting of the trigger  20  can enable a conical spray of low to high diameter (see  FIGS. 4 , and  7 - 9 ). At third position, the forward-most rotational position of trigger  20  is set near the trigger&#39;s backward-most rotational position so that a conical spray exits from the spray gun  10 , and then if desired further backward pivot of the trigger  20  may enable fine tuning of conical spray diameter (see FIGS.  4 A and  10 - 12 ). Intermediate positions between or about the first, second, and third positions may also be provided to set the desired forward-most trigger rotational position and thus the spray shape from shut off. Further, mechanism  23  enables the operator to select a desired spray shape or shut off without any manual pressure upon the trigger  20  against the bias of spring  44 . Thus, unlike the prior art spray guns utilizing external manual nozzle rotation which often results in operator fluid contact to select desired spray shape or shut off, the operator of spray gun  10  can set the spray gun on to a desired spray shape or shut off without any such possible fluid contact, and if desired, can further control the spray shape from a desired set spray shape, stream or conical, such as at the second or third positions, respectively. 
         [0038]    From the foregoing description, it will be apparent that there has been provided an improved spray gun which provides variable and selectable flow patterns depending upon the position of a manually actuable trigger lever. Variations and modifications in the herein described spray gun within the scope of the invention will undoubtedly suggest themselves to those skilled in the art. Accordingly, the foregoing description should be taken as illustrative and not in a limiting sense.