US3443578A - Color select valve for spray guns - Google Patents

Description

May 13, 1969 R. s. HEDIN COLOR SELECT VALVE FOR SPRAY GUNS INVENIOR. Rosa-er S. l/azwv Filed Oct. 12. 1966.

May 13, 1969 R. s. HEDIN 3,443,578

COLOR SELECT VALVE FOR SPRAY GUNS Filed Oct. 12, 1966 7 Sheet 2 of 2 P/POMJMMFD OR M00004 SP/Pfl 601V 1 N VEN TOR.

B Y J/ M W LMWM United States Patent 3,443,578 COLOR SELECT VALVE FOR SPRAY GUNS Robert S. Hedin, Minneapolis, Minn., assignor to Programmed & Remote Systems Corporation, St. Paul, Minn., a corporation of Minnesota Filed Oct. 12, 1966, Ser. No. 586,102 Int. Cl. F161: 25/02, /22, 5/12 US. Cl. 137-240 3 Claims ABSTRACT OF THE DISCLOSURE The present invention has relation to multiple passageway valves and more particularly to a valve for controlling the How of one of a plurality of diflferent colors of paint to a spray gun in response to remote signals.

The present invention provides for remote operation of a valve assembly to direct one of a plurality of colors of paint to a spray gun. More particularly, it relates to a valve which is manufactured conveniently without close tolerances and yet will operate satisfactorily in automatic paint spraying installations. Each of the paint colors is controlled by a separate valve mounted in the valve body, and also, means are provided for purging or cleaning the paint passageways when a different color paint is to be used.

The device is adapted readily to either manual or automatic operation and can be used with any type of conventional spray gun. The multiple passageway valve is designed to be extremely economical to make, compact in size and designed to use a minimum of solvent in purging the gun and passageways between colors. Further, it is designed so that there is a minimum of color intermix ing when diiferent color paints are used interchangeably.

Therefore, it is an object of the present invention to present a compact, easily manufactured, multiple passageway valve assembly.

It is another object of the present invention to present a multiple passageway valve assembly for paints which includes means for purging the passageways when different color paints are to be used.

It is another object of the present invention to present a multiple passageway valve having individually controlled ports that are capable of being operated remotely in response to a pre-programmed signal, or in response to manual operation.

It is still a further object of the present invention to present a multiple passageway valve body wherein the valving assembly can easily be inserted and removed from the valve body.

It is another object of the present invention to present a multiple passageway valve assembly for controlling a plurality of different color paints which has a separate system for purging the valve assembly and the spray gun after a painting operation.

It is another object of the present invention to present a multiple passageway valve assembly wherein the valves are arranged in an annular ring around the valve body and wherein the purging system is centrally located in the body.

3,443,578 Patented May 13, 1969 It is still a further object of the present invention to present a multiple passageway valve body for paints wherein the valves themselves are arranged in an annular ring around the body and wherein the valves are used for controlling a constantly circulating paint supply at each of the valves, thereby having inlets and return paint conduits to each of the valves.

Other objects are inherent in the specification and will become apparent as the description proceeds.

In the drawings,

FIGURE 1 is an end elevational view of a valve assembly with parts in section and parts broken away;

FIGURE 2 is a longitudinal sectional view of a valve assembly made according to the present invention taken as on line 2-2 in FIGURE 1 and including a schematic representation of certain components; and- FIGURE 3 is a sectional view taken as on line 33 in FIGURE 2.

Referring to the drawings and the numerals of reference thereon, a valve assembly illustrated generally at 10 includes a main valve housing 11 having an open interior chamber 12 and a plurality of annularly disposed chambers 13 around and adjacent to the outer periphery thereof. As shown, an annular groove 14 is defined in the housing, and this actually separates the chambers 13 into two sections so that there is an open area in the middle area of each of the chambers 13 or, in other words, between the sections of the chamber. The chambers 13 extend in axial direction along the length of the housing. A cover member 15 is sealingly attached to one end of the housing and the cover member has an annular groove or chamber 16 defined therein. The chamber 16 aligns with all of the chambers 13 and acts as a collector chamber. An outlet connection port 17 is provided in the cover member 15 and this port opens into the annular groove or chamber 16. The port 17 is used for attachments of conduits leading. to a spray gun illustrated schematically at 20. The spray gun can be of any usual or preferred construction.

As shown, the valve body has sixteen of the chambers 13 arranged around the periphery thereo f. A separate, constantly open paint inlet port 21 is provided at each of the chambers 13 on the outer surface of the valve body. The ports 21 open into passageways 22 (one for each of the chambers 13) which extend inwardly in radial direction for a short distance and then go parallel to the chainbers 13 in direction away from the cover member 15. The passageways 22 terminate at the outer end of the valve body and a separate paint line illustrated at 23 is connected to each of these passageways 22 at the outer end thereof. The ports 21 are connected to paint lines 24 leading from a pump 25 which in turn pumps paint from a supply 26 through the port 21 and into the chambers 13, out through passageways 22 and then through the lines 23 back to the particular paint supply.

A separate set of paint conduits and a separate supply is used for each of the chambers 13, and therefore each of the chambers can handle a different color of paint. The return lines 23 can have restrictions therein to maintain the pressure in chambers 13 above that in ring chamber 16 or at the spray gun.

Each of the chambers 13 houses a separate control valve assembly 30. The valve assemblies are all identical and are shown typically in FIGURE 2. The valve assembly 30 includes a valve seat member 31 which sits inside the chamber 13 adjacent the cover member 15. As shown, the valve seat member 31 has a neck portion 32 that fits inside a narrowed portion of the chamber 13. The neck portion includes a valve seat face 33 defined at the end of an interior chamber in the valve seat member and the seat 'face surrounds a valve controlled port 34 which communicates with the annular groove or collector chamber 16 in the cover member 15. The neck portion 32 also has openings 35 which communicate with the port or opening 21 and passageway 22 to permit paint to flow through the interior of the valve seat member and out through the passageway 22, when the port 34 is closed.

The rear portions of the valve seat member have internal threads 36 into which a packing nut 37 can be threadably mounted. Suitable packing 38 is placed into the interior chamber of the valve seat member and this surrounds a needle valve 40 which is mounted for longitudinal sliding movement with respect to the packing nut and with respect to the valve seat member 31. As shown, the end of the needle valve adjacent port 34 is tapered and mates with the valve seat face 33 so that when they are in contact, flow through port 34 is shut off.

An additional lubricating packing 41 is utilized with the needle valve to keep it lubricated.

The rear portion or section of chamber 13 comprises a cylinder section 54 for mounting the actuating devices for the needle valve 40. As shown, a collar 42 is mounted against a shoulder in the chamber 13 and this collar 42 has an O-ring 43 which fits against the needle valve 40 and seals the interior of the rear portion of the chamber 13 from the atmosphere. A piston member 44 is slidably mounted in the chamber 13 and mounts the needle valve 40. As shown, a set screw 45 is used for fixing the needle valve with respect to the piston and as shown the needle valve can be provided with a head to hold it in place. The piston is also sealed with respect to the outer surface of the cylinder portion of chamber 13 with an O-ring 46. A spring 47 is mounted within a provided recess in the piston 44. A cover ring 50 is fastened to the valve body member 11, and is of size to cover the chambers 13 at that end of the valve body. As shown, the ring 50 then holds the spring 47 in place, and the spring 47 urges the needle valve in direction as indicated by the arrow 51 so that it will seat down against the valve seat face 33 and normally hold the port 34 closed.

An inlet 53 is provided into the interior of the cylinder section 54 between the collar 42 and the inner end of the piston 44. A conduit shown schematically at 55 leading from a solenoid valve 56 which in turn controls air under pressure from a source 57 is connected to the inlet 53. The solenoid valve 56 (there is one actuating valve for each of the chambers 13) is controlled either by a pre-programmed device which automatically turns the valve on or oil? in response to an external signal or by manual controls illustrated schematically at 60.

Whenever a particular color of paint is desired in the spray gun, the proper control is actuated and the solenoid valve 56 for the proper one of the chambers 13 is energized directing air under pressure into the connected cylinder 54.

Once fluid under pressure is introduced into the cylinder 54, this will force the piston 44 in direction opposite that indicated by the arrow 51 moving the needle valve 40 away from the valve seat at 33 and opening the connection between the inlet 21 for the paint and the port 34 so that the paint (which is under pressure from restrictors) will flow into the annular chamber 16, and out through the port 17 to the spray gun 20. This particular color of paint will then be sprayed from the gun.

It can easily be seen that the device can be programmed to dispense any particular color desired. When the spray pattern is finished, the solenoid valve 56 will be deenergized permitting the spring 47 to return the needle valve to its seat and closing off that port 34.

In order to clean the chamber 16, and the spray gun and conduits of paint, a solvent and air purge is used. This is done by directing air under pressure with a solvent aspirated into the air stream through a solenoid valve control 62 which also can be controlled from the programming or manual control 60, or separate controls tfor first solvent and then air according to the needs of the user. The solenoid valve will direct the solvent and air through a conduit illustrated schematically at 63 into a fitting 64. The fitting 64 opens into a passageway 65 defined in the valve body. A ball check valve 66 held in place with a spring 67 seats against the interior edge of the fitting 64 to seal off this passageway 65 when there is a back pressure in the passageway. The passageway 65 extends radially outwardly between two of the chambers 13 and opens into the annular groove or chamber 16 as shown at 68.

Thus, solvent and air under pressure from the source illustrated schematically at 69, once the valve 62 is opened, will go through the fitting 64, unseat the ball check valve 66 against the action of spring 67 and this solvent and air mixture will pass through the passageway 65 into the annular chamber 16 and out through the conduits to the spray gun 20. The solvent and air will clean out the passageways so that all of the previous paint will be removed. The solenoid valve 62 will then be shut olf and the next color of paint can be sprayed through the gun merely by actuating the control for the desired solenoid valve 56 or by having this done automatically in a pre-programming system.

By arrangement of the chambers 13 annularly around the center of the valve member and by having full flow of paint through the chambers 13, a great saving in space is effected.

Also, by using valve seat member inserts in the chambers 13, the cost of producing the valve assembly is reduced because precision machining does not have to be done inside the bores of the chamber 13.

It should be noted that normally the spray gun will have an on-oif control so that the color of paint can be selected by actuating one of the needles 40 before the paint is actually dispensed. Then, when the gun control is actuated, the paint will be sprayed.

What is claimed is:

1. A valve assembly for controlling discharge of any one of a plurality of colors of paint through a single conduit from a plurality of supply lines, said valve assembly comprising a cylindrical body, a plurality of first chambers defined in said body and arranged with their axes substantially parallel and lying in annular orientation spaced from and around the axis of said body, an annular tubular groove defined in an end portion of said body and forming a collector chamber, each of said first chambers being open through a separate control port coaxial with the first chamber to said collector chamber, said single conduit being also open to said collector chamber, means delivering a separate supply of a different color of paint to each of said first chambers, said paint being maintained under pressure greater than atmosphere in said first chambers, each of said first chambers being divided into first and second sections, said first section including said control port and separate paint supply inlet and return ports, a separate valve member in each of said first sections, said valve members each being movable from a valve seating position closing the control port leading to said collector chamber, to a position wherein said control port leading to said collector chamber is open, said second sections each comprising a cylinder housing, a piston in said housing and operably attached to the valve member in the associated first section, bias means to urge said valve members toward the valve seating position, means to selectively admit air under pressure to each of said cylinder sections of said chambers to move said pistons in direction against said bias means to move the associated valve members to open position, and separate means positioned within the annular ring of first chambers to supply a paint solvent to said collector chamber.

2. The valve assembly according to claim 1 further characterized in that said supply inlet port and supply outlet port in each of said first sections are unaffected by movement of said valve member, and means to circulate the supply of paint through said first sections from the inlet 5 6 port to the outlet port Whenever the control port for the References Cited associated first section is closed. UNITED STATES PATENTS 3. The valve assembly of claim 1 further characterized in that solvent is supplied from a solvent source through g gg a centrally located passageway positioned within the space 5 324O225 3/1966 Barrow; bounded by said first chambers in their annular arrange- 3373762 3/1968 Kurchak 155 XR ment, a radial passageway in said housing leading from u said centrally located passageway to said collector cham- JOHN PETRAKES, primary Examiner ber, and check valve means in said centrally located passageway to prevent paint from moving from the collector 10 U.S. Cl. X.R. chamber to said solvent source. 137602, 606

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