Patent Publication Number: US-6705545-B1

Title: Quick color change powder paint system

Description:
This application is a continuation-in-part of application No. 09/628,634, filed Jul. 31, 2000 (now U.S. Pat. No. 6,315,214, issued Nov. 13, 2001) entitled METHOD FOR CONTROLLING POWDER PAINT SYSTEM, which is a continuation of application No. 09/191,892, filed Nov. 13, 1998 (now U.S. Pat. No. 6,112,999, issued Sep. 5, 2000) entitled POWDER PAINT SYSTEM AND CONTROL THEREOF. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention concerns a powder paint system that includes an arrangement permitting quick color change and that minimizes paint lost when making the color change. 
     Colored powder paint must be completely purged from a paint line and spray gun, particularly when changing from a dark color to a light color, so that residue paint from the previous color does not discolor the next color. A problem is that this leads to slow cycle times, wasted labor, and process inefficiencies. Also, existing purge methods lead to considerable waste in the form of purged material that must be landfilled, which could be very expensive, particularly if the landfilled materials are potential pollutants to the environment. 
     Some manufacturers have chosen to use a different paint line and spray gun for each color. However, this requires a large capital expenditure for equipment. Further, the equipment takes up space and each station requires constant maintenance and upkeep, whether or not it is used. 
     Another problem is that the particles of the powder paint will degrade if kept in a fluidized state ready for use over long periods of time. Powder paints must be fluidized (i.e., suspended in air or a gaseous carrier), so that a uniform and steady flow of particles of powder paint can be picked up and carried to a part upon demand. Degradation occurs because collisions between particles affect the particle surfaces and also cause the particles to become smaller in size. Where a high voltage charge is used to assist in depositing the powder paint onto a part, the degraded powder materials have a reduced ability to pick up or hold a high voltage charge. 
     Accordingly, an apparatus solving the aforementioned disadvantages and having the aforementioned advantages is desired. 
     SUMMARY OF THE INVENTION 
     One aspect of the present invention is to provide at least one spray gun, a paint line changing assembly and a plurality of differently colored paint sources. The paint line changing assembly is configured to selectively connect the at least one spray gun with one of the plurality of differently colored paint sources. The paint system further includes a controller for maintaining at least one of the plurality of differently colored paint sources in a partially fluidized state when not connected to the at least one spray gun and for maintaining the one of the plurality of differently colored paint sources in an operative fluidized state when connected to the at least one spray gun. 
     Another aspect of the present invention is to provide a method of painting including providing at least one spray gun, a paint line changing assembly and a plurality of differently colored paint sources. The method also includes selectively connecting the at least one spray gun to one of the plurality of differently colored paint sources with the paint line changing assembly. At least one of the plurality of differently colored paint sources is maintained in a partially fluidized state when not connected to the at least one spray gun and the one of the plurality of the differently colored paint sources is maintained in an operative fluidized state when connected to the at least one spray gun. 
     Yet another aspect of the present invention is to provide a paint system including a paint line changing assembly and a plurality of differently colored paint sources. The paint line changing assembly is configured to automatically and selectively connect at least one spray gun with one of the plurality of differently colored paint sources. The paint system also includes a controller for maintaining at least one of the plurality of differently colored paint sources in a partially fluidized state when not connected to the at least one spray gun and maintaining the one of the plurality of differently colored paint sources in an operative fluidized state when connected to the at least one spray gun. 
     In yet another aspect of the present invention, a paint system is provided wherein the paint system includes a plurality of differently colored paint sources, a purging air source, a spray gun and a paint line changing assembly. The paint line changing assembly includes a first manifold and a second manifold. The first manifold includes an axis and a plurality of first passageways parallel to the axis of the first manifold, with each of the first passageways of the first manifold being in fluid communication with one the plurality of differently colored paint sources and the air source. The second manifold includes an axis and a second passageway parallel to the axis of the second manifold. The second passageway of the second manifold is in fluid communication with the spray gun. The second manifold is also rotatably connected to the first manifold along their respective axes. The plurality of passageways in the first manifold are configured to be automatically and selectively aligned with the passageway of the second manifold, thereby automatically fluidly connecting one of the plurality of differently colored paint sources or the air source to the spray gun. 
     Another aspect of the present invention is to provide a paint system having a plurality of differently colored paint sources, a plurality of spray guns and a paint line changing assembly. The paint line changing assembly includes a first body and a second body. The first body includes a plurality of sets of first passageways, with each set of first passageways being in fluid communication with a different one of the plurality of different paint sources. The second body includes a set of second passageways in fluid communication with the plurality of spray guns. The paint system further includes a support for the first and second bodies. One of the first body and the second body is configured to move relative to the support in a first direction parallel to the longitudinal direction. Moreover, the other of the first body and the second body is configured to move in a second direction different from the first direction to selectively align one of the sets of first passageways in the first body with the set of second passageways of the second body, thereby fluidly connecting one of the plurality of differently colored paint sources to the plurality of spray guns. 
     The principal objects of the present invention include providing a paint system for quickly changing the color of powder paint. The paint system can be used automatically to paint various items or products. The paint system can also be used to automatically and repetitively paint items or products with different colors. Therefore, the paint system provides reduced manufacturing costs for painting items or products. The paint system further prevents color cross contamination of a subsequent color sprayed. The paint system is efficient in use, economical to manufacture, capable of a long operable life, and particularly adapted for the proposed use. 
    
    
     These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims and appended drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a paint system embodying the present invention. 
     FIG. 2 is a front view of a first body and a second body of a first embodiment of a paint line changing assembly of the present invention. 
     FIG. 3 is a bottom view of the first body of the first embodiment of the paint line changing assembly of the present invention. 
     FIG. 4 is a side view of the first body and the second body of the first embodiment of the paint line changing assembly of the present invention. 
     FIG. 5 is a front view of a first body and a second body of a second embodiment of the paint line changing assembly of the present invention. 
     FIG. 6 is a side view of the first body of the second embodiment of the paint line changing assembly of the present invention. 
     FIG. 7 is a side view of the second body of the second embodiment of the paint line changing assembly of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as orientated in FIG.  1 . However, it is to be understood that the invention may assume various alternative orientations, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. 
     The reference number  10  (FIG. 1) generally designates a paint system embodying the present invention. In the illustrated example, the paint system  10  includes at least one spray gun  14 A- 14 D, a paint line changing assembly  16  and a plurality of differently colored paint sources  18 A- 18 E. The paint line changing assembly  16  is configured to selectively connect the at least one spray gun  14 A- 14 D with one of the plurality of differently colored paint sources  18 A- 18 E. The paint system  10  further includes a controller  20  for maintaining at least one of the plurality of differently colored paint sources  18 A- 18 E in a partially fluidized state when not connected to the at least one spray gun  14 A- 14 D and for maintaining the one of the plurality of differently colored paint sources  18 A- 18 E in an operative fluidized state when connected to the at least one spray gun  14 A- 14 D. 
     In the illustrated paint system  10 , the at least one spray gun  14 A- 14 D is located within a spray booth  12  and the paint line changing assembly  16  is positioned outside of the spray booth  12 . The illustrated spray guns  14 A- 14 D are configured to paint products (not shown) traveling through the spray booth  12  with powdered paint. The products can travel through the spray booth  12  on a conveyor belt  26 , in any other manner or could be stationary. Furthermore, the products could be traveling on devices such that the products would be spun, raised, lowered, etc. in order to thoroughly paint the entire product. In the illustrated example, four spray guns  14 A- 14 D are located within the spray booth  12 , although, the spray booth  12  could employ any number of spray guns. The illustrated spray guns  14 A- 14 D are preferably locked in a fixed position within the spray booth  12  in order to automatically paint the products by forcing powdered paint out of the nozzles of the spray guns  14 A- 14 D as the products pass by the spray guns  14 A- 14 D. The spray guns  14 A- 14 D are electronically connected to the controller  20  for triggering the flow of paint from the spray guns  14 A- 14 D and for controlling the electrostatic charges generated in the spray guns  14 A- 14 D for charging the powder paint to assist in depositing the powder paint on the products. The spray guns  14 A- 14 D are preferably horizontally and vertically adjustable so the spray guns  14 A- 14 D can be positioned to properly and thoroughly paint the products. Although the spray guns  14 A- 14 D are locked in a fixed position in the spray booth  12  for automatic painting, the spray guns  14 A- 14 D could also be allowed to move within the spray booth  12  and could include triggers for manually spraying the products. Spray guns  14 A- 14 D, electrical controls and means for controlling the electrostatic charges are known in the art, such that they do not need to be described for a complete understanding of the present invention. Each of the spray guns  14 A- 14 D include a spray gun hose  34 A- 34 D extending from the spray guns  14 A- 14 D to the paint line changing assembly  16  for delivering powdered paint to the spray guns  14 A- 14 D. Four spray gun hoses  34 A- 34 D are shown in FIG. 1 because four spray guns  14 A- 14 D are shown, but any number of spray gun hoses could be used, depending on the number of spray guns. 
     In the illustrated example, the controller  20 , the paint line changing assembly  16  and a plurality of differently colored paint sources  18 A- 18 E are located outside of the spray booth  12 . With the controller  20 , paint line changing assembly  16  and paint sources  18 A- 18 E being located outside of the spray booth  12 , the above elements can be controlled, changed, worked on, etc. by a person without the person coming into contact with the powdered paint typically floating about in the spray booth  12 , thereby providing a better working environment. Furthermore, locating the paint line changing assembly  16  outside of the spray booth  12  allows it to be readily accessible to a technician. The controller  20  includes a programmable logic controller (PLC) and could be located anywhere in the building housing the spray booth  12 . The controller  20  can be programmed to automatically activate the spray guns  14 A- 14 D, generate electrostatic charges in the spray guns  14 A- 14 D, and as discussed in more detail below, connect the spray guns  14 A- 14 D with one of the plurality of different colored paint sources  18 A- 18 E, purge paint in the paint system  10 , maintain at least one of the plurality of differently colored paint sources  18 A- 18 E in the partially fluidized state and maintain one of the plurality of differently colored paint sources  18 A- 18 E in the operative fluidized state. Controllers  20  are known in the art, such that they do not need to be described for a complete understanding of the present invention. 
     The illustrated paint line changing assembly  16  is connected to each of the spray gun tubes  34 A- 34 E linked to the spray guns  14 A- 142  and also to a plurality of sets of source tubes  42 A,  42 B, etc. Each set of source tubes  42 A,  42 B, etc. is shown as containing four source tubes. For example, a first set includes four of the source tubes  42 A. However, like the spray gun hoses, the number of source tubes in each set depends on the number of spray guns. Five of the sets of source tubes  42 A- 42 E are linked to one of the plurality of different colored paint sources  18 A- 18 E (although each set of source tubes  42 B- 42 E between sources  18 B- 18 E and the paint line changing assembly  16  are shown as one dashed line), respectively, and one set of source tubes  42 F is connected to a purging air source and valving control box assembly  40  for purging the paint system  10 , as described in more detail below. Although six sets of source tubes  42 A- 42 F are shown in FIG. 1, the number of source tubes can vary, depending on the number of differently colored paint sources. For example, if there are seven differently colored paint sources, the paint system  10  would require eight source tubes (seven source tubes for the differently colored paint sources and one source tube for the purging air source and valving control box assembly  40 ). The paint line changing assembly  16  is configured to selectively connect the spray gun tubes  34 A- 34 D to one of the sets of source tubes  42 A- 42 F for connecting the spray guns  14 A- 14 D with one of the differently colored paint sources  18 A,  18 B, etc. or the source tube  42 F for connecting the spray guns  14 A- 14 D to the purging air source and valving control box assembly  40 . For example, the paint line changing assembly  16  can connect all of the spray guns  14 A- 14 D to the first set of source tubes  42 A, and therefore to one of the plurality of differently colored paint sources  18 A. 
     In the illustrated example, each of the plurality of differently colored paint sources  18 A- 18 E includes a supply tank or canister  44 A- 44 E containing powdered paint. To avoid repetitious and redundant discussion, the features and components for one of the canisters  44 A will be described, it being understood that identical features and components for each of the canisters will have identical numbers for identical features and components, but with the addition of the letters “A,” “B,” “C,” “D” and “E” for the features and components of each canister  44 A- 44 E. The canister  44 A is fluidly connected to the paint line changing assembly  16  and to the purging air source and valving control box assembly  40 . Powder fluidization line  46 A extends from a fluidization valving arrangement in the purging air source and valving control box assembly  40  to a bottom of the canisters  44 A. The illustrated canister  44 A is barrel shaped, optimally suited for providing a swirling fluidizing action to suspend powder paint particles. The canister  44 A includes an upper chamber  48 A for holding fluidized powder paint and a lower chamber  50 A for receiving fluidization air from the fluidization line  46 A that passes upwardly into the upper chamber  48 A. A porous filter/wall  52 A separates the upper and lower chambers  48 A and  50 A and permits the fluidizing air to flow upwardly from the lower chamber  50 A into the upper chamber  48 A in a manner fluidizing the powder paint. This keeps the powder paint suspended and dispersed, so that it is ready to be carried to the spray guns  14 A- 14 D for application. A powder delivery airflow line  54 A and a powder atomization line  56 A extend from the respective valving arrangement in the purging air source and valving control box assembly  40  to a pump. 58 A on the top of the canister  44 A. The airflow line  54 A provides the airflow to pump  58 A necessary to provide a venturi effect to suck fluidized powder paint into the air stream traveling along the source tubes  42 A to the spray guns  14 A- 14 D. The atomization line  56 A provides an additional volume of air that is necessary to create the total airflow desired. The atomization air lets the speed of the total airflow and also the dispersion of powder paint in the total airflow to be adjusted to desired values for optimal painting. A vent line  60 A extends from a top of the canister  44 A for venting excess fluidization air fed into the canister  44 A. The illustrated pump  58 A includes a suction tube  62 A that extends about ⅔ of the way down into the canister  44 A. Notably, although a specific supply tank is shown, it is contemplated that the present invention is broad enough to include various tank configurations and pump arrangements, and accordingly the present description of these components is intended only to facilitate an understanding of the present invention. Although only one canister  44 A is illustrated as being connected to each of the source tubes  42 A, each source tube  42 A could be connected to a different canister  44 A, with each canister  44 A containing an identical color of powdered paint. A paint line changing assembly that can be automated, and the above features and components for one of the canisters  44 A, the purging air source and the valving control box are the subject matter of commonly assigned U.S. Pat. No. 6,112,999, hereby incorporated by reference, except that in the present invention one of the sets of source tubes  42 F is permanently connected to the source of purging air, the source of purging air forces powdered paint through the spray gun hoses  34 A- 34 E instead of back into the canisters  44 A- 44 E and the controller  20  controls all of the systems in the valving control box and an air to gun control valve. 
     The illustrated purging air source and valving control box assembly  40  is configured, under direction from the controller  20 , to maintain at least one of the plurality of differently colored paint sources  18 A- 18 E in a partially fluidized state when not connected to the at least one spray gun  14  and to maintain one of the plurality of differently colored paint sources  18 A- 18 E in an operative fluidized state when connected to the spray guns  14 A- 14 D by providing a selected amount of air through the selected powder fluidization line  46 A- 46 E. The paint sources  18 A- 18 E in the partially fluidized state are at a standby fluidization pressure that is adjusted by regulator to a minimum pressure condition to minimize particle degradation over time, but so that the particles of powder paint are sufficiently suspended to prevent agglomeration and to allow a quick increase to the operational airflow/pressure without undue delay. The paint sources  18 A- 18 E in the operative fluidized state are in an operating condition, wherein the particles of the powder paint are excited to a higher state such that they are optimally suspended to be drawn into the airflow traveling through the source tubes  42 A- 42 E to the spray guns  14 A- 14 D for application to a part. For example, this fluidization pressure may be about double the standby fluidization pressure. It is noted that the standby and operational fluidization pressures are very dependent upon the length and size of hoses and the supply lines, the input main air pressure, the equipment, the powder paint, and the components used in the overall system  10 . 
     The illustrated paint line changing assembly  16  (FIGS. 24) includes a first body  64  positioned adjacent a second body  66 . As described in more detail below, the first body  64  is in fluid communication with the plurality of differently colored paint sources  18 A- 18 E and the second body  66  is in fluid communication with the spray guns  14 A- 14 D. The first body  64  and the second body  66  are connected to a support, shown as a movable rack  22  in FIG.  1 . The support  22  could also be any wall of the building that houses the spray system  10  or any other movable support. The illustrated first body  64  comprises a first rectangular block  68  with a plurality of sets of parallel first passageways  70 A- 70 F (with  70 A- 70 E shown in phantom in FIG. 3) extending from a bottom surface  72  of the first rectangular block  68  to a top surface  74  of the first rectangular block  68  in a four by six matrix, with each set of first passageways  70 A,  70 B, etc. being in a four by one matrix. The number of sets of first passageways can vary, depending on the number of differently colored paint sources (similar to the number of source tubes described above). Furthermore, the number of first passageways in each set can vary, depending on the number of spray guns (similar to the number of spray gun hoses described above). In FIG. 2, the sets of first passageways  70 A- 70 F extend in a longitudinal direction defined by the axis of each of the first passageways  70 A- 70 F. The second body  66  comprises a second rectangular block  76  with a set of second parallel passageways  78 A- 78 D extending from a bottom surface  80  of the second rectangular block  76  to a top surface  82  of the second rectangular block  76  in a four by one matrix. The number of second passageways can vary, depending on the number of spray guns (similar to the number of spray gun hoses described above). Each passageway of the set of second passageways  78 A- 78 D has the same distance between each one of them as the distance between each passageway of one of the sets of first passageways  70 A- 70 F. Furthermore, each passageway of the plurality of sets of first passageways  70 A- 70 F and the set of second passageways  78 A- 78 D are parallel. The second body  66  is configured to move relatively to the first body  64  in order to selectively align one of the sets of first passageways  70 A- 70 F in the first body  64  with the set of second passageways  78 A- 78 D in the second body  66 . 
     In the illustrated example, each of the first passageways  70 A- 70 F of the first body  64  has a fitting  84  extending into the first passageways  70 A- 70 F from the top  74  of the first body  64  (shown in phantom in FIGS. 2 and 4) and extending outwardly from the top  74  of the first body  64  for connection to the source tubes  42 A- 42 F. The fittings  84  preferably include an enlarged middle portion  86  and are placed into the first passageways  70 A- 70 F until the enlarged middle portion  86  abuts the top of the first body  64 . The fittings  84  have tapered ends  88  and are preferably connected to the first body  64  and the source tubes  42 A- 42 F with an interference fit. Therefore, each of the first passageways  70 A- 70 F are fluidly connected to a differently colored paint source  18 A- 18 E or the purging air source and valving control box assembly  40 . In the illustrated example, each set of first passageways  70 A- 70 F are fluidly connected to one of the paint canisters  44 A- 44 E or the purging air source and valving control box assembly  40  such that all but one set of the first passageways  70 A- 70 E is connected to one color of paint (the set of first passageways  70 F is connected to the purging air source and valving control box assembly  40 ). Each of the first passageways  70 A- 70 F also include an enlarged opening or counterbore  90  adjacent the bottom  72  of the first body  64 . As explained in more detail below, each enlarged opening  90  accepts an enlarged head  92  of a partial fitting  94  on the second body  66  for selectively fluidly connecting the set of second passageways  78 A- 78 D to one of the sets of first passageways  70 A- 70 F. 
     Each of the illustrated second passageways  78 A- 78 D of the second body  66  includes a fitting  84  similar to the fittings  84  of the first body  64  extending into the second passageways  78 A- 78 D from the bottom  80  of the second body  66  and extending outwardly from the bottom  80  of the second body  66  for connection to the spray gun hoses  34 A- 34 D connected to the spray guns  14 A- 14 D. The fittings  84  of the second body  66  also have tapered ends  88  and preferably include the enlarged middle portion  86 . The fittings of the second body  66  are placed into the second passageways  78 A- 78 D until the enlarged middle portion  86  abuts the bottom  80  of the second body  66 . The fittings  84  are preferably connected to the second body  66  and the spray gun hoses  34 A- 34 D with an interference fit. Therefore, each of the second passageways  78 A- 78 D is fluidly connected to a spray gun  14 A- 14 D. The second body  66  also  5  has the partial fitting  94  extending into the second passageways  78 A- 78 D from the top  82  of the second body  66 . The partial fittings  94  also include enlarged heads  92  similar to the enlarged middle portions  86  of the fittings  84 , with the enlarged heads  92  abutting the top  82  of the second body  66 . The heads  92  also include an extended cylindrical portion  96  having an inside diameter equal to the inside diameter of the fittings  84 . The heads  92  help to fluidly connect one of the sets of first passageways. 70 A- 70 F to the set of second passageways  78 A- 78 D. 
     In the illustrated example, the second body  66  is configured to move vertically and the first body  64  is configured to move horizontally, with the top  82  of the second body  66  abutting the bottom  72 , of the first body  64  when the second body  66  is at the top of its vertical stroke. The first body  64  moves horizontally in predetermined increments (shown in phantom in FIG. 2) such that one of the sets of first passageways  70 A- 70 F is aligned with the set of second passageways  78 A- 78 D after each incremental movement. When the bottom  72  of the first body  64  abuts the top  82  of the second body  66 , the heads  92  extending from the top  82  of the second body  66  are accepted into the enlarged openings  90  of one of the sets of first passageways  70 A- 70 F of the first body  64 , thereby fluidly connecting the set of first passageways  70 A- 70 F to the set of second passageways  78 A- 78 D. Furthermore, the second body  66  has a greater length than the first body  64  such that all of the first passageways not connected to the set of second passageways  78 A- 78 D are covered at the bottom  72  of the first body  64  by the top  82  of the second body  66 . The second body  66  moves vertically with a stroke large enough for the heads  92  to exit the enlarged openings  90  and allow the first body  64  to move horizontally. 
     The illustrated first body  64  and the second body  66  are connected by vehicles the support  22 , wherein the vehicles  98  move the first body  64  and the second body  66  in the respective directions. In the illustrated example, the vehicles  98  are shown as comprising a pair of pillow blocks  100 . The pair of pillow blocks  100  attached to the first body  64  are arranged horizontally and ride on a horizontal first rail  102  attached to the support  22 . The pair of pillow blocks  100  attached to the second body  66  are arranged horizontally and ride on a pair of vertical second rails  104  attached to the support  22 . The first body  64  and the second body  66 , or the pillow blocks  100  of the first body  64  and the second body  66 , can be moved linearly with pneumatic or hydraulic cylinders, an electromagnetic device such as a solenoid or linear actuator, or any other device that could move the bodies. 
     The paint line changing assembly  16  connects the spray guns  14 A- 14 D with one of the differently colored paint sources  18 A,  18 B, etc. by first moving the second body  66  to the bottom of its stroke such that the enlarged heads  92  of the partial fittings  94  of the second body  66  are not located within the enlarged openings  90  of the first body  64 . Thereafter, the first body  64  is moved horizontally until the desired set of first passageways  70 A- 70 F connected to the desired differently colored paint source  18 A,  18 B, etc. or the purging air source and valving control box assembly  40  is aligned with the set second passageways  78 A- 78 D of the second body  66 . The second body  66  is then moved upward with the heads  92  entering the enlarged openings  90  of the desired set of first passageways  70 A- 70 F. The spray guns  14 A- 14 D are therefore fluidly connected to the desired differently colored paint source  18 A,  18 B, etc. The first body  64  and the second body  66  could also be moved with any vehicle or in any direction as long as the desired set of first passageways  70 A- 70 F is aligned with the set of second passageways  78 A- 78 D after each movement. Furthermore, it is contemplated that one of the first body  64  and the second body  66  could move in more than one direction with the other of the first body  64  and the second body  66  remaining stationary, thereby aligning the desired set of first passageways  70 A- 70 F with the set of second passageways  78 A- 78 D and moving the first body  64  and the second body  66  together. 
     When a change of the color of powdered paint is desired for the spray guns  14 A- 14 D, the controller  20  will first command the spray guns  14 A- 14 D to stop spraying the powdered paint. Thereafter, the second body  66  will move vertically downward until the heads  92  of the second body  66  are no longer within with the enlarged openings  90  of the first body  64 . The first body  64  is then moved horizontally until the set of first passageways  70 A- 70 F connected to the purging air source and valving control box assembly  40  is aligned with the set of second passageways  78 A- 78 D. The second body  66  is then moved upward until the heads  92  are within the enlarged openings  90  of the set of first passageways  70 A- 70 F connected to the source tubes  42 F connected to the purging air source and valving control box assembly  40 . A meter amount of compressed air from the purging air source and valving control box assembly  40  is then blown through the source tubes  42 F, the set of first passageways  70 A- 70 F, the set of second passageways  78 A- 78 D, the spray gun tubes  34 A- 34 D and the spray guns  14 A- 14 D. The compressed air forces any of the previous powdered paint remaining in the above elements through the sprays guns  14 A- 14 D and into the spray booth  12  for collection. Thereafter, the second body  66  will once again move vertically downward until the heads  92  of the second body  66  are no longer within the enlarged openings  90  of the first body  64 . The first body  64  is then moved horizontally until the set of first passageways  70 A- 70 F connected to another desired differently colored powdered source  18 A,  18 B, etc. is aligned with the set of second passageways  78 A- 78 D. The second body  66  is then moved upward until the heads  92  are within the enlarged openings  90  of the set of first passageways  70 A- 70 F connected to source tubes  42 A- 42 E connected to another desired differently colored powdered source  18 A,  18 B, etc. The process described directly above is repeated every time a change in powdered paint color is desired. In this manner, the paint system  10  can sequentially, repetitively and automatically paint a plurality of the products with different colors of paint. Furthermore, all of the movements of the first body  64  and the second body  66  are automatically controlled by the controller  20 , although the first and second body  66  could be moved manually if a controller  20  is not running the paint system  10 . 
     The reference numeral  216  (FIGS. 5-7) generally designates another embodiment of the present invention, having a second embodiment for the paint line changing assembly. Since paint line changing assembly  216  is similar to the previously described paint line changing assembly  16 , similar parts appearing in FIGS.  24  and FIGS. 5-7, respectively, are represented by the same, corresponding reference number, except for the prefix “2” in the numerals of the latter. The illustrated paint line changing assembly  216  is configured to be attached to only one spray gun  14 A to one of a plurality of different paint sources  18 A- 18 E or the purging air source and valving control box assembly  40 . However, many paint line changing assemblies  216  could be used if many spray guns are employed, with one paint line changing assembly  216  for each spray gun. 
     The illustrated paint line changing assembly  216  includes a first body  264  positioned adjacent a second body  266 . The first body  264  is in fluid communication with the plurality of differently colored paint sources  18 A- 18 E and the second body  266  is in fluid communication. with the spray gun  14 A. The first body  264  and the second body  266  are connected to a support, such as the rack  22  in FIG. 1 or any other support. The illustrated first body  264  comprises a first manifold  300  with a plurality of parallel first passageways  270 A- 270 F extending from a first side  302  of the first manifold  300  to a second side  304  of the first manifold  300 . The second body  266  comprises a second manifold  306  with a second passageway  278 A extending from a first side  306  of the second manifold  308  to a second side  310  of the second manifold  306 . Although the first manifold  300  and the second manifold  306  are shown in FIGS. 5-7 as having a hexagonal cross section, the first manifold  300  and the second manifold  306  could have a circular cross section, or any other geometric cross section. The second manifold  306  is configured to move relative to the first manifold  300  in order to selectively align one of the first passageways  270 A- 270 F in the first manifold  300  with the second passageway  278 A in the second manifold  306 . 
     In the illustrated example, each of the first passageways  270 A- 270 F of the first manifold  300  have fittings  284  extending into the first passageways  270 A- 270 F. The fittings  284  are connected to the source tubes  42 A- 42 F, thereby fluidly connecting each of the first passageways  270 A- 270 F to a differently colored paint source  18 A- 18 E or the purging air source and valving control box assembly  40 . In the illustrated example, each of the first passageways  270 A- 270 F is configured to be fluidly connected to one of the paint canisters  44 A- 44 E or the purging air source and valving control box assembly  40  such that all but one of the first passageways  270 A- 270 E is connected to one color of paint. Each of the first passageways  270 A- 270 F also include enlarged openings  290  adjacent the second side  304  of the first manifold  300 . Each enlarged opening  290  is configured to accept an enlarged head  292  of a partial fitting  294  on the second manifold  306  for selectively fluidly connecting the second passageway  78 A to one of the first passageways  270 A- 270 F. 
     The illustrated second passageway  278 A of the second manifold  306  includes a fitting  284  extending into the second passageway  78 A from the second side  310  of the second manifold  306  for connection to the spray gun hose  34 A connected to the spray gun  14 A. Therefore, the second passageway  78 A is fluidly connected to the spray gun  14 A. The second manifold  306  also has the partial fitting  294  extending into the second passageway  78 A from the first side  308  of the second manifold  306 . The partial fitting  94  includes the enlarged head  292 . The head  292  helps to fluidly connect one of the first passageways  270 A- 270 F to the second passageway  78 A. 
     In the illustrated example, the second manifold  306  is configured to move horizontally and the first manifold  300  is configured to rotate, with the first side  308  of the second manifold  306  abutting the second side  304  of the first manifold  300  when the second manifold  306  is at the bottom of its stroke. The first manifold  300  rotates in predetermined increments A′-F′ (see FIG. 6) such that one of the first passageways  270 A- 270 F is aligned with the second passageway  78 A after each incremental rotation. When the second side  304  of the first manifold  300  abuts the first side  308  of the second manifold  306 , the head  292  extending from the first side  308  of the second manifold  306  is accepted into the enlarged opening  290  of one of the first passageways  270 A- 270 F of the first manifold  300 , thereby fluidly connecting one of the first passageways  270 A- 270 F to the second passageway  78 A. The second manifold  306  therefore moves horizontally with a stroke large enough for the head  292  to exit the enlarged opening  290  and allow the first manifold  300  to rotate. The first manifold  300  can be rotated with a servomotor, or pneumatic or hydraulic cylinders or motors mechanically linked to the first manifold  300  via a control arm, gearing or precision belt/pulley arrangements. The second manifold  306  can be moved linearly with pneumatic or hydraulic cylinders, an electro-magnetic device such as a solenoid or linear actuator. The first manifold  300  and the second manifold  306  could also be moved by any other device that could move the bodies. The second manifold  306  preferably includes a cylindrical handle  320  extending from the center of the second side  310  of the second manifold  306  for manually pulling the second manifold  306  away from the first manifold  300  and for manually rotating the second manifold  306  relative to the first manifold  300 . 
     The paint line changing assembly  216  connects the spray gun  14 A with one of the differently colored paint sources  18 A,  18 B, etc. by first moving the second manifold  306  away from the first manifold  300  such that the enlarged head  292  of the partial fitting  294  of the second manifold  306  is not located within the enlarged opening  290  of the first manifold  300 . Thereafter, the first manifold  300  is rotated until the desired first passageway  270 A- 270 F connected to the desired differently colored paint source  18 A,  18 B, etc. or the purging air source and valving control box assembly  40  is aligned with the second passageway  78 A of the second manifold  306 . The second manifold  306  is then moved back towards the first manifold  300  with the head  292  entering the enlarged opening  290  of the first passageway  270 A,  270 B, etc. The spray gun  214 A is therefore fluidly connected to the desired differently colored paint source  18 A,  18 B, etc. 
     When a change of the color of powdered paint is desired for the spray gun  14 A, the controller  20  will first command the spray gun  14 A to stop spraying the powdered paint. Thereafter, the second manifold  306  will move away from the first manifold  300  until the head  292  of the second manifold  306  is no longer within with the enlarged opening  290  of the first manifold  300 . The first manifold  300  is then rotated until the first passageways  70 F connected to the purging air source and valving control box assembly  40  is aligned with the second passageway  278 A. The second manifold  306  is then moved towards the first manifold  300  until the head  292  is within the enlarged opening  290  of the first passageway  270 A connected to the source tubes  42 F connected to the purging air source and valving control box assembly  40 . Air from the purging air source and valving control box assembly  40  is then blown through the source tube  42 F, the first passageway  270 A,  270 B, etc., the second passageway  278 A, the spray gun tube  34 A and the spray gun  14 A, thereby cleaning the powdered paint out of the above elements. Thereafter, the second manifold  306  will once again move away from the first manifold  300  until the head  292  of the second manifold  306  is no longer within the enlarged opening  290  of the first manifold  300 . The first manifold  300  is then rotated until the first passageways  70 A- 70 F connected to another desired differently colored powdered source  18 A,  18 B, etc. is aligned with the second passageway  78 A. The second manifold  306  is then moved towards the first manifold  300  until the head  292  is within the enlarged opening  290  of the first passageways  270 A- 270 E connected to source tubes  42 A- 42 E connected to another desired differently colored powdered source  18 A,  18 B, etc. The process described directly above is repeated every time a change in powdered paint color is desired. In this manner, the paint system  10  can sequentially, repetitively and automatically paint a plurality of products with different colors of paint. Furthermore, all of the movements of the first manifold  300  and the second manifold  306  are automatically controlled by the controller  20 , although the first manifold  300  and second manifold  306  could be moved manually if a controller  20  is not running the paint system  10 . 
     When the paint line changing assembly  216  is configured to be manually controlled, a pin  330  located in the first manifold  300  and the second manifold  306  helps to bias the first manifold  300  and the second manifold  306  together. The illustrated pin  330  extends along the axis of the first manifold  300  and is positioned in an axial opening  332  located in the second side  304  of the first manifold  300 . A first end  333  of the pin  330  is connected to a fastener  334  extending through the first side  302  of the first manifold  300  and into the axial opening  332 . A second end  336  of the pin  330  extends outwardly from the second side  304  of the first manifold  300 . The second manifold  306  includes an axial bore  338 , with the pin  300  extending into the axial bore  338  of the second manifold  306 . A fastener  340  on the second end  336  of the pin  330  extends into a small bore  342  aligned with the axial bore  338  in a central portion of the second manifold  306 . An annular wall  344  with a circular opening  346  is located between the axial bore  338  and the small bore  342  of the second manifold  306 , with the fastener  340  attached to the pin  300  extending through the circular opening  346 . A coil spring  348  smaller than the small bore  342  but larger than the circular opening  346  is located in the small bore  342  and connected to the fastener  340 , such that the coil spring  348  does not fit within the circular opening  346 . The coil spring  348  therefore attaches the first manifold  300  to the second manifold  306  by retaining the second end  336  of the pin  330  of the first manifold  300  within the second manifold  306 . The coil spring  348 , however, is free to rotate within the second manifold  306  such that the first manifold  300  and the second manifold  306  are rotatably connected. The coil spring  348  also biases the pin  330  such that the first manifold  300  and the second manifold  306  are biased towards each other along their respective axes. Therefore, the second manifold  306  can be pulled away from the first manifold  300  with the handle  320  to index the second passageway  278 A with one of the first passageways  270 A- 270 F and the second manifold  306  will therefore be forced towards the first manifold  300  after the indexing by the force of the coil spring  348 . 
     The above description is considered that of the preferred embodiments only. Modification of the invention will occur to those skilled in the art and to those who make or use the invention. For example, liquid paint of other liquids can be sprayed through the spray guns, with the spray gun hoses, the source tubes and the paint line changing assembly being flushed with a flushing liquid instead of air. Therefore, it is understood that the embodiments shown in the drawings and described above are merely for illustrative purposes and not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including doctrine of equivalents.