Patent Publication Number: US-6338439-B1

Title: Nozzle assembly

Description:
FIELD OF THE INVENTION 
     This invention relates to a nozzle assembly and more particularly, to a nozzle assembly which selectively emits material through an aperture at a relatively uniform velocity. 
     BACKGROUND OF THE INVENTION 
     Nozzles selectively emit various types of materials, such as and without limitation paint, thereby placing or depositing the selectively emitted material upon various objects and/or target locations in some desired pattern and/or concentration. Oftentimes it is highly desirable to place or deposit the emitted material on the targeted object and/or location in a substantially uniform concentration, thereby substantially preventing uneven material deposits which are unsightly and unaesthetic. 
     Moreover, it is also desirable to provide for the selective emission, by the nozzle, of a mixture of liquid and solid particles and/or a mixture of gas and solid particles in order to allow the nozzle to be used within a wide variety of applications requiring different types of materials. 
     While prior nozzle assemblies adequately and selectively emit material, they do not substantially ensure that the emitted material is uniformly placed upon the targeted object or location. Rather these prior nozzle assemblies typically emit a greater amount of the material through a center portion of the nozzle and lesser amounts around the nozzle end portions, thereby undesirably creating areas of relatively high material concentration upon the targeted object or location. 
     That is, the portion of the material which traverses the middle or center of the nozzle assembly has a greater velocity than those material portions which traverse the outer portions of nozzle assembly, thereby causing the material to have a non-uniform velocity profile as the material exits the outlet apertures of these nozzle assemblies (e.g. the velocity of the emitted material is not uniform at substantially every point or location within the outlet aperture). Hence, more material is deposited through the center portion of the respective outlet apertures of these prior nozzle assemblies than is deposited through the outer edge portions of the respective outlet apertures of these prior nozzle assemblies. 
     Moreover, while these prior nozzle assemblies allow for the selective emission of such liquid-solid and gaseous-solid mixtures, they must often and/or frequently be “unclogged” or cleaned since the solid particles tend to form undesirable and flow-restricting deposits within these prior nozzle assemblies. These “cleanings” reduce the overall efficiency and increase the cost of the material application process and further increase the non-uniformity of the velocity profile of the emitted material. Further, as new types of solid particles and/or materials are used by these prior nozzle assemblies, the respectively contained particle deposits become undesirably mixed with the new material, thereby undesirably contaminating the new material. 
     There is therefore a need for a new and improved nozzle assembly which allows for the selective emission of material having a substantially uniform velocity, which allows the selectively emitted material to be substantially and uniformly deposited upon a target object and/or location, which allows for the selective emission of material having a liquid and a solid component and/or material having a gaseous and a solid component, and which substantially prevents and/or reduces undesirable material deposits within the nozzle assembly. 
     SUMMARY OF THE INVENTION 
     It is a first object of the invention to provide a nozzle assembly which overcomes some or all of the previously delineated drawbacks of prior nozzle assemblies. 
     It is a second object of the invention to provide a nozzle assembly which overcomes some or all of the previously delineated drawbacks of prior nozzle assemblies and which allows material to be selectively emitted with a substantially uniform velocity profile. 
     It is a third object of the invention to provide a nozzle assembly which overcomes some or all of the previously delineated drawbacks of prior nozzle assemblies and which allows material to be selectively emitted and to be substantially and uniformly deposited upon a target object and/or location. 
     It is a fourth object of the invention to provide a nozzle assembly which overcomes some or all of the previously delineated drawbacks of prior nozzle assemblies and which allows mixtures of diverse types of material to be selectively emitted. 
     According to a first aspect of the present invention a nozzle assembly is provided. The nozzle assembly includes an outlet aperture having a first portion of a first cross sectional area and a second portion having a second cross sectional area, the second cross sectional area being smaller than the first cross sectional area. 
     According to a second aspect of the present invention a nozzle assembly is provided. The nozzle assembly is of the type which receives material and which emits the received material through an outlet aperture. The nozzle assembly includes a first narrow portion which receives the material and a second wider portion which communicates with the first portion and with the outlet aperture and which communicates the material to the outlet aperture. 
     According to a third aspect of the present invention a method is provided for use with a nozzle of the type having an outlet aperture. The nozzle is of the type which receives material and which selectively emits the received material through the outlet aperture. The method is effective to cause the material to be emitted at a substantially uniform pressure and includes the steps of causing a first portion of the outlet aperture to have a first cross sectional area and causing a second portion of the outlet aperture to have a second cross sectional area. 
     These and other features, aspects, and advantages of the invention will become apparent by reference to the following specification and by reference to the following drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side-sectional view of a nozzle assembly which is made in accordance with the teachings of the preferred embodiment of the invention; 
     FIG. 2 is a view of the nozzle assembly which is shown in FIG.  1  and which is taken in the direction of arrow  2 ; 
     FIG. 3 is a side sectional view of a nozzle assembly which is made in accordance with the teachings of a second embodiment of the invention; 
     FIG. 4 is a graph of the pressure distribution within the nozzle assembly which is shown in FIG. 3; 
     FIG. 5 is a side view of the nozzle assembly shown in FIG.  1  and which is operatively attached to a sprayer; and 
     FIG. 6 is a perspective view of an injection element which is contained within the nozzle assembly which is shown in FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION 
     Referring now to FIGS. 1,  2 ,  5 , and  6 , there is shown a nozzle assembly  10  which is made in accordance with the teachings of the preferred embodiment of the invention. Particularly, nozzle assembly  10  includes a first inlet aperture portion  12  which receives a first material  14  which is to be selectively emitted from assembly  10 . In the preferred embodiment of the invention, material  14  comprises gaseous material. Nozzle assembly  10  further includes a second or outlet aperture portion  16  which is cooperatively comprised of and/or which includes several apertures  18 ,  20 ,  22 ,  24 , and  26  which are respectively separated by substantially identical, generally ellipsoidal, and integrally formed elements  28 ,  30 ,  32 , and  34 . Each element  28 - 34  has a generally “C”-shaped notch or groove  36  which is positioned within the outlet aperture  16 . As shown, element  28  cooperates with the top portion  38  of nozzle assembly  10  to form a passage or channel  40  which extends from the inlet aperture  12  to the aperture  18 ; elements  28  and  30  cooperatively form a channel or passage  42  which extends from the inlet aperture  12  to the aperture  20 ; elements  30  and  32  cooperatively form a passage or channel  44  which extends from the inlet aperture  12  to the aperture  22 ; elements  32  and  34  cooperatively form a passage or channel  46  which extends from the inlet aperture  12  to the aperture  24 ; and element  34  cooperates with the bottom portion  48  of the nozzle assembly  10  to form a passage or channel  50  which extends from the inlet aperture  12  to the aperture  26 . 
     It should be realized that a different number and/or shape of apertures  18 - 26  may be used in other embodiments and that a different number and/or shape of elements  28 - 34  may be used in other embodiments of the invention. It should be further realized that elements  28 - 34  may each be selectively coupled to a source or receptacle  35  of solid or liquid particulate. In such an embodiment, the liquid and/or solid particulate material is selectively emitted from notches  36 , such as by use of a tube (not shown) which is receivably contained within notches  36  and which is physically and communicatively coupled to source  35 . In other alternate embodiments, other elements may be used to form channels  40 - 50 , and elements  28 - 34  may be disposed in different locations upon and/or within nozzle assembly  10 . 
     It should further be appreciated that channel  44  is relatively narrower than channels  40 ,  42 ,  46 , and  50 , and that channels  42  and  46  have substantially the same width and are narrower than channels  40  and  50 . In one non-limiting embodiment, channels  42  and  46  are substantially similar in size and shape and channels  40  and  50  are substantially similar in size and shape. 
     As best shown in FIG. 2, in this non-limiting embodiment of the invention, apertures  18  and  26  have a substantially identical, respective, and relatively large and generally rectangular cross sectional area  52 ,  54 ; apertures  20 ,  24  have a substantially identical, respective, and generally rectangular cross sectional area  56 ,  58  which is smaller than the cross sectional areas  52 ,  54 ; and aperture  22  has a generally rectangular cross sectional area  60  which is smaller than any and all of the cross sectional areas  52 ,  54 ,  56 , and  58 , and which is generally symmetrical about the longitudinal axis of symmetry  62  of the nozzle assembly  10 . In this manner, it should be appreciated that the aperture  22  resides within the middle portion of the outlet aperture  16 . 
     Nozzle assembly  10  further includes substantially identical and generally ellipsoidal elements  64 ,  66 ,  68 ,  70 , and  72  which are respectively disposed within the channels  40 - 50  and within the apertures  18 - 26 . Each of the elements  64 - 72  includes a generally “C”-shaped notch  74  which communicates with the outlet aperture  16 . Elements  64 - 72  are each communicatively coupled to a source or receptacle  73  of liquid and/or solid particulate, such as by use of a tube which is receiveably contained within each element  64 - 72  and which is physically and communicatively coupled to source  73 , such as tube  100  which is shown in FIG.  6 . In one non-limiting embodiment of the invention, each element  64 - 72  is substantially identical in shape to the elements  28 - 34 . Further, nozzle assembly  10 , in one non-limiting embodiment, includes generally rectangular “blocking” elements  76 - 84  which are respectively deployed within channels  40 - 50  in relatively close proximity to the inlet aperture  12 . In one non-limiting embodiment, elements  76  and  84  are substantially identical, as are elements  78  and  82 . Further, in one non-limiting embodiment, substantially identical elements  76  and  84  are larger than substantially identical elements  78  and  82 , and element  80 , which is disposed upon the axis  62 , is substantially smaller than any of the elements  76 ,  78 ,  82 , and  84 . In another non-limiting embodiment of the invention, each of the elements  76 - 84  are substantially similar and/or identical. In any of these non-limiting embodiments, it should be realized that element  80  is slightly thinner than the width of the channel  44 , thereby residing within most of the space formed between the end portions of members  30 ,  32  which are proximate to the inlet aperture  12 , and allowing received material  14  to enter channel  44  through relatively narrow openings  86 ,  88 . Concomitantly, elements  78  and  82  respectively form substantially identical entry openings  90 ,  92  and  94 ,  96  within respective channels  42  and  46 . Openings  90 ,  92  are substantially larger than are openings  86 ,  88 . Further, elements  76 ,  84  respectively form substantially identical entry openings  98 ,  100 , and  102 ,  104  within respective channels  40  and  50 . Openings  98  and  100  are substantially larger than openings  94 ,  96  and  86 ,  88 . Each element  76 - 84 ,  28 - 34 , and  64 - 72  may be selectively formed by a silicon micro-machining process. 
     As best shown in FIG. 5, nozzle assembly  10  may be attached to a conventional sprayer or spray gun  77 . Gas enters spray gun  77  through hose  79 . Solid and/or liquid material is communicated to notches  36  from receptacle  35  and solid and/or liquid material is communicated to notches  74  from receptacle  73 . 
     In operation, gas is injected into the inlet aperture  12 . The injected gas, comprising material  14 , enters the channels  40 - 50  through the respective opening pairs  98 ,  100 ;  90 ,  92 ;  86 ,  88 ;  94 ,  96 ; and  102 ,  104 . The gas traverses these channels  40 - 50  and is mixed with liquid and/or solid particles at the outlet aperture  16 . More particularly, the liquid and solid particulate material is placed within the outlet aperture  16  by the elements  28 - 34  and/or by the elements  64 - 72  and, more particularly, selectively emanate from the notched portion  36  of elements  28 - 34  and/or from the notched portion  74  of the elements  64 - 72 . The mixture of the gaseous, liquid, and solid particulate material is then emitted from the nozzle assembly  10 . 
     Importantly, the relatively narrow middle channel openings  86 ,  88  cooperate with the relatively narrow middle channel  44  to reduce the velocity of the material  14  which traverses the channel  44 . Further, the relatively wide channel openings  98 ,  100  and  102 ,  104  cooperate with the relatively wide end channels  40 ,  50  to allow material  14 , which traverses the channels  40 ,  50 , to be relatively un-hindered and to have a velocity which is substantially similar to the velocity of the material  14  which traverses channel  44 . Further, the openings  90 ,  92  and  94 ,  96  cooperate with the relatively narrow channels  42 ,  46 , which are adjacent to the central or middle channel  44 , to cause the velocity of the material  14  which traverses these channels  42 ,  46  to be substantially similar to the velocity of the material  14  which traverses channels  40 ,  50 , and  44 , thereby allowing the material  14  and/or material mixture to be emitted at a substantially similar and/or uniform velocity at each point or location within the outlet aperture  16 . The previously delineated arrangement also substantially ensures that the amount of emitted material  14  and/or the amount of the emitted material mixture, emanating from the aperture  16 , is substantially similar at each point or location within the aperture  16 , thereby allowing for the application and/or emanation of substantially uniform concentrations of the emitted material  14 . 
     A second embodiment of the present invention is illustrated in FIG.  3 . Nozzle assembly  120  is generally cylindrical and includes a tapered or “narrowed” portion or section  122  in which the diameter  126  of the nozzle assembly  10  decreases along a path or direction beginning at location “A” and ending at location “B”, and a relatively rapidly “expanding” portion or section  124  which is immediately adjacent to section  122 . Within section  124 , the diameter  126  of the nozzle assembly  10  substantially and relatively rapidly increases from location “B” to a location “C”. Two substantially identical and generally ellipsoidal elements  128 ,  130  are disposed in relative remote proximity to outlet aperture  132  of nozzle assembly  120 . Elements  128 ,  130  each include a generally “C”-shaped notch  134  which is communicatively coupled to a particulate reservoir or receptacle  136 , and which emits certain amounts of liquid and/or solid particulate  138  which is desired to be mixed with gaseous material  140 . 
     In operation, gaseous material  140  is accelerated to relatively high and/or supersonic speeds and is communicated to nozzle assembly  120  through input aperture  142 . A region of relatively low pressure is created within nozzle assembly  120  by rapidly expanding section  124 . The pressure characteristics within nozzle assembly  120  are illustrated by graph  150  shown in FIG.  4 . As shown, the pressure, within nozzle  120 , reaches a minimum value in relative close proximity to location “C”, which corresponds to the location at which notches  134  emit the liquid and/or solid particulate material  138 . This arrangement allows nozzle assembly  120  to automatically entrain particulate material  138 , thereby substantially obviating the need for a liquid flow-control valve and/or reducing the demands on such a valve. This novel arrangement further allows solid particulate to be introduced along with the gaseous material  140  within the outlet aperture  132 , thereby reducing the susceptibility of nozzle  120  to clogging. 
     It is understood that the invention is not limited by the exact construction or method illustrated and described above but that the various changes and/or modifications may be made without departing from the spirit and/or the scope of Applicants&#39; inventions.