US3403818A - Portable airless sprayer - Google Patents

Description

O 19 B. E. ENS'SL: 3,403,818

PORTABLE AIRLESS SPRAYER Filed Sept. 30, 1966 2 Sheets-sheet 1 flrazzo E Izzssfe ,&4 f

United States Patent 3,403,818 PORTABLE AIRLESS SPRAYER Bruno Eugen Enssle, Boulder, Colo., assignor to Binks Research and Development Corporation, Boulder, (1010., a corporation of Colorado Filed Sept. 30, 1966, Ser. No. 583,259 Claims. (Cl. 222-23) ABSTRACT OF THE DISCLOSURE Portable airless sprayer apparatus for spraying paint or the like including an improved cylinder structure with a free floating piston therein and improved valve means for controlling the flow of spray material into the cylinder and the discharge of such material therefrom, and further including an airless spray system where a cylindrical vessel of the foregoing type serves as an accumulator so as to permit a constant flow of material into the cylindrical vessel while a variable amount of spray material is being discharged therefrom.

The present invention relates to an airless spraying apparatus suitable for the spraying of paint or various other fluids and which is particularly adapted for use as a portable sprayer remote from the original source of spray material and pump supply means. The sprayer of the present invention is also adapted to function as an accumulator when used in combination with a source of spray material and a pump for supplying such material under pressure.

It is known in the art to provide a sprayer of the type where the spray material is motivated by a gaseous charge, but with most such devices the gaseous charge is consumed during a spraying operation and the device is not reusable. The present invention relates to a sprayer of a type which is filled with a charge of gas under pressure for forcing the spray material out of the sprayer at a sufficient volume and pressure to accomplish airless spraying, and the device is so designed that the gaseous material is not consumed during a spraying operation. Consequently, paint stores or the like can supply to a home owner or small industrial user a portable airless spray unit having a predetermined capacity, e.g., one gallon, and after the spray material is used up the device may be returned to the dealer for subsequent refilling with spray material and without need for replenishing the gaseous charge.

It is therefore a general object of the present invention to provide an improved portable spray device where the spray is propelled by a gaseous charge which is not consumed during a spraying operation.

Another object of the invention is to provide an improved portable airless sprayer having improved measuring means for indicating the amount of spray material contained within the sprayer.

A further object of the invention is to provide an improved airless spray apparatus which when used in combination with a source of spray material and pump means for supplying such material under pressure will function as an accumulator so as to continuously receive spray material under pressure and accumulate the same while being capable of intermittently discharging such material in an airless spray at the control of an operator.

Still another of my objects is to provide an improved portable spray device which can be used in combination with one or more additional spray devices of like construction to provide a portable multi-component spray system.

The foregoing and other objects and advantages of the invention will be apparent from the following description thereof.

3,403,818 Patented Oct. 1, 1968 Now, in order to acquaint those skilled in the art with the manner of making and using my invention, I shall describe in conjunction with the accompanying drawings certain preferred embodiments of the invention.

In the drawings:

FIGURE 1 is a schematic elevational view, partly in section, showing an airless spray system including a portable airless spray device constructed in accordance with the present invention;

FIGURE 2 is an enlarged vertical sectional view, partly broken away, of a portable airless spray device which may be connected to a spray gun through a suitable hose connection in order to adapt the unit for a spraying operation;

FIGURE 3 is a top plan view of the spray device of FIGURE 2 showing a pressure gage mounted on the top of the unit and calibrated so as to indicate the pressure in an upper chamber thereof; and

FIGURE 4 is a perspective view showing a multicomponent airless spray system in the form of a portable back pack comprising a pair of like spray units constructed in accordance with the present invention and connected with a common spray gun for producing a multi-component airless spray.

Referring now to the drawings, FIGURE 1 shows a supply vessel 10 containing paint or other fluid material to be sprayed, a pump 12, hose means 14 extending from the pump to the supply vessel, a portable airless spray unit 16, hose means 18 connecting the pump 12 with the spray unit 16, and an airless spray gun 20 connected by hose means 22 to the spray unit 16. As will be explained more fully hereinafter, the pump 12 serves to draw paint or other spray material from the vessel 10 and deliver the same under pressure to a lower chamber 24 in the spray unit 16 where the paint is stored or accumulated and drawn off when needed through operation of the spray gun 20. An upper chamber 26 in the spray unit 16 is supplied with a gaseous charge under pressure which acts upon a movable piston 28 so as to force the spray material from the lower chamber 24 through the hose 22 and out through the spray gun 20 to produce an airless spray. If the spray unit 16 is used for a spraying operation while connected to the pump 12 by means of the hose 18, then the pump may be utilized to continuously supply spray material under pressure to the chamber 24, and the spray gun 20 may be operated intermittently as desired in order to withdraw spray material from the chamber 24 and produce an airless spray of such material. In an application of the latter type the spray unit 16 functions as an accumulator so as to compensate for variations between the volume of spray material being supplied by the pump 12 and the volume of spray material being delivered through the spray gun 20. On the other hand, once the spray unit 16 has received a supply of spray material from the pump 12, the hose 18 may be disconnected from the spray unit and the latter together with the spray gun 20 and hose means 22 may be transported to any desired location remote from the container 10 and pump 12 and used as a portable spray unit to provide an airless spray of paint or other fluid material.

FIGURE 2 shows the spray unit 16 comprising a cylinder 30 sealed at its upper end by a cylinder head 32 and at its lower end by a cylinder head 34. The cylinder 30 is provided adjacent its upper end with an internal groove 36 in which an annular snap ring 38 is disposed for retaining the upper cylinder head 32 in position within the cylinder. In a similar manner, the cylinder 30 is provided adjacent its lower end with an internal groove 7 40 in which an annular snap ring 42 is disposed for retaining the lower cylinder head 34 in position within the cylinder. The upper cylinder head 32 has an external groove 44 in which an O-ring seal 46 and a back-up ring 48 are positioned, and the lower cylinder head 34 has an external groove 50 in which an O-ring seal 52 and a back-up ring 54 are positioned. In addition, the movable piston 28 is provided with a pair of external grooves 56 and 58 in which a pair of O- rings 60 and 62 are located. Accordingly, the lower chamber 24 defined between the piston 28 and the cylinder head 34, and the upper chamber 26 defined between the piston 28 and the cylinder head 32, are each effectively sealed so as to be capable of containing a fluid under pressure.

The upper cylinder head 32 is provided with a pair of apertures 64 and 66 which extend completely through the head so as to communicate with the upper chamber 26. A pressure gage 68 having a mounting shaft 70 is disposed above the head 32 with the shaft 70 threaded into the aperture 64 so that the gage will indicate the pressure in the chamber 26. A conventional filler check valve 72 is threaded into the aperture 66 so as to provide a means for supplying a fluid under pressure to the upper chamber 26. A filler block 74 is secured to the bottom of the lower cylinder head 34 by four cap screws 76. An inlet fitting 78 is threaded into one side of the filler block 74, and a ball valve 80 is connected at the opposite side of the filler block.

The ball valve 80 includes a manually operable handle 82, and also includes an outlet fitting 84 for connection with the hose 22 (see FIGURE 1) which leads to the spray gun 20. An internal chamber 86 is formed in the filler block 74, and the chamber 86 communicates with the inlet fitting 78 and also with the manually operable ball valve 80. In addition, a bore 88 in the filler block 74 and a coaxial bore 90 in the cylinder head 34 permits the internal chamber '86 in the filler block to communicate with the lower pressure chamber 24 in the cylinder 30. A ball 92 is disposed in the chamber 86 and cooperates with the fitting 78 to provide an inlet check valve which permits fluid to be delivered to the chamber 24 when supplied at a pressure exceeding the pressure therein.

In operation, a gas, e.g. nitrogen, is supplied through the filler check valve 72 to the upper chamber 26 causing the piston 28 to move to the lower end of the cylinder 30. In the particular example being described it will be assumed that the gas is supplied until the gage 68 shows a pressure of 1000 p.s.i., although other gas pressures may be utilized, preferably in the range of 100 p.s.i. to 1500 p.s.i. It will be seen from FIGURE 3 that the gage 68 includes an indicator needle 94, and a dial 96 which is marked so as to designate a preferred gas pressure of approximately 1000 p.s.i. and a normal operating range beginning at 1000 p.s.i. and extending to 2500 p.s.i., above which the dial is marked danger. After the upper chamber 26 is charged with gas, the conduit 18 of FIGURE 1 is connected to the inlet fitting 78 and the pump 12 is operated to supply paint or other spray material under pressure from the container to the lower chamber 24. As the spray material is pumped under pressure to the lower chamber 24, the piston 28 moves upwardly so as to compress the gaseous charge in the chamber 26. In the particular embodiment being described the spray material is preferably introduced into the chamber 24 until the pressure gage 68 indicates a pressure of approximately 2500 p.s.i., meaning that the gas in the chamber 26 and the spray material in the chamber 24 are both at a pressure of 2500 p.s.i.

After the supply of spray material has been pumped into the chamber 24, the supply conduit 18 may be disconnected from the fitting 78 and the spray unit 16 together with the hose 22 and airless spray gun may be transported and used at any desired location remote from the supply container 10 and pump 12. Whenever the spray gun 20 is operated, the gaseous charge in the chamber 26 will move the piston 28 downwardly so as to force the spray material in the chamber 24 out through the spray gun 20 at a pressure and volume suflicient to accomplish airless spraying. As the spray material is used up the piston 28 will gradually move toward the bottom of the cylinder, and the pressure within the two chambers 24 and 26 will decrease until the piston 28 has reached the bottom of the cylinder at which time the pressure in the upper chamber 26 will be equal to the initial gas pressure of 1000 p.s.i.

It will be understood that the gaseous charge in the chamber 26 is not consumed during a spraying operation and will thus last indefinitely. It will further be understood that the pressure gage 68 will serve to indicate the amount of spray material contained within the chamber 24. For example, if the spray unit 16 has a capacity of one gallon of spray material when such material is supplied until the pressure gage indicates 2500 p.s.i., and assuming as previously described that the initial charge of gas is at a.- pressure of 1000 p.s.i., it will then be known that a pressure reading of 1000 p.s.i. indicates the chamber 24 is empty, while a pressure reading of 2500 p.s.i. indicates a full supply of one gallon of spray material. Intermediate pressure readings will indicate proportionate intermediate amounts of spray material in the chamber 24, and if desired the pressure gage dial 96 may be calibrated in gallons or the like to provide a direct reading of the amount of spray material contained within the unit.

The preferred construction of the spray unit 16 is as shown in FIGURE 2 where the upper cylinder head 32 is recessed relative to the end of the cylinder 30 so as to provide a space 98 within the upper end of the cylinder for accommodating the pressure gage '68 and the filler valve 72. Similarly, the lower cylinder head 34 is recessed relative to the lower end of the cylinder thereby providing a space 100 within the cylinder to accommodate the filler block 74, inlet fitting 78 and ball valve 80. It will be seen that a hole 102 is formed in one side of the cylinder wall to permit access to the inlet fitting 78, while a second hole 104 is formed in the opposite side of the cylinder wall so as to provide an opening for the outlet fitting 84. The valve handle 82 is of course accessible from the open lower end of the cylinder.

It should be understood that if desired the spray unit 16 may be operated while connected to the supply pump 12 as shown in FIGURE 1. Thus, the pump may be operated so as to continuously supply paint or other spray material under pressure to the chamber 24, and the spray material may be drawn intermittently from the chamber 24 as needed by operation of the' spray gun 20, or if desired a plurality of spray guns may be connected to a common spray unit 16. The spray unit 16 under such circumstances will act as an accumulator and the piston 28 will move upwardly or downwardly depending upon whether the supply of spray material in the chamber 24 is increasing or decreasing.

FIGURE 4 shows a portable back pack assembly 106 comprising a pair of spray units 16' and 16" each substantially identical to the spray unit 16 of FIGURE 2. The assembly 106 is intended to provide a portable multicomponent airless spray system, e.g., a portable spray unit for producing foam suitable for use in the foam sealing of mine tunnels. There are two ingredients for the foam, one being contained under pressure in the spray unit 16 and the other being contained under pressure in the unit 16". The two spray units 16' and 16" are connected to a common spray gun 108 by respective hose means 110 and 112. The two foam ingredients are-mixed in the gun 108 which controls the relative amounts thereof. In the spraying of foam it is necessary to flush the mixing chamber of the spray gun after each use in order to prevent the foam from hardening in the gun, and for this purpose there is shown a solvent flush bottle 114 which is connected to the gun 108 through a hose 116. If desired, the two spray units 16 and 16" and the solvent flush bottle 114 may be secured to a common mounting member 118 and strapped to the back of an operator thereby providing a highly practical portable multi component spray unit.

The portable spray unit shown in FIGURE 2 is adaptable for use in the airless spraying of a multitude of difierent materials, and is particularly suitable for airless paint spraying. It is also important to understand that while the portable spray unit of the present invention may be constructed in various sizes, it is possible because of the economies of airless spraying to spray a very substantial area with a limited amount of spray material. For example, generally speaking a portable spray unit having a one gallon capacity will hold sufiicient paint to cover a two-car garage.

While I have described my invention in certain preferred forms, I do not intend to be limited to such forms, except insofar as the appended claims are so limited, since modifications within the scope of my invention will readily occur to those skilled in the art, particularly with my disclosure before them.

-I claim:

1. A portable airless spray device for airless spraying of paint or other fluid spray materials comprising, in combination, a hollow cylindrical body member, first head means sealing one end of said body member, second head means sealing the other end of said body member, a piston disposed within said cylindrical body member intermediate said first and second head means and longitudinally movable therein, said piston serving to divide the interior of said body member into a first chamber between said piston and said first head means and a second chamber between said piston and said second head means, first inlet means communicating with said first chamber for supplying a gas thereto, said first chamber being filled with gas under pressure, second inlet means communicating with said second chamber for supplying spray material under pressure thereto, outlet means communicating with said second chamber for connection with airless spray gun means whereby upon operation of said spray gun means said gas will move said piston to ward said second chamber forcing said spray material to said spray gun at a volume and pressure sufificient to accomplish airless spraying without consuming the gas in said first chamber, a filler block secured to the outside of said second head means, said second inlet means comprising a fitting secured to said filler block and communicating with an interior chamber in said filler block, a movable ball disposed in the interior chamber in said filler block for cooperation with said fitting to comprise an inlet check valve, aperture means connecting said interior chamber in said filler block with said second chamber in said cylindrical body member, and said outlet means including a manually operable valve connected with said filler block in communication with said interior chamber therein.

2. A portable airless spray device for airless spraying of paint or other fluid spray materials comprising, in combination, a hollow cylindrical body member, first head means sealing one end of said body member, second head means sealing the other end of said body member, a piston disposed within said cylindrical body member intermediate said first and second head means and longitudinally movable therein, said piston serving to divide the interior of said body member into a first chamber between said piston and said first head means and a second chamber between said piston and said second head means, first inlet means communicating with said first chamber for supplying a gas thereto, said first chamber being filled with gas under pressure, second inlet means communicating with said second chamber for supplying spray material under pressure thereto, outlet means communicating said said second chamber for connection with airless spray gun means whereby upon operation of said spray gun means said gas will move said piston toward said second chamber forcing said spray material to said spray gun at a volume and pressure sufficient to accomplish airless spraying without consuming the gas in said first chamber, said first head means comprising a first disc-shaped member secured within one end of said hollow cylindrical body member in a recessed position relative thereto to define a first open space within the end of the body member, said second head means comprising a second disc-shaped member secured within the other end of the body member in a recessed position relative thereto to define a second open space within the other end of the body member, said first inlet means being disposed in said first open space, and said second inlet means and said outlet means being disposed in said second open space.

3. A portable airless spray device for airless spraying of paint or other fluid spray materials comprising, in combination, a hollow cylindrical body member, first head means sealing one end of said body member, second head means sealing the other end of said body member, a piston disposed within said cylindrical body member intermediate said first and second head means and longitudinally movable therein, said piston serving to divide the interior of said body member into a first chamber between said piston and said first head means and a second chamber between said piston and said second head means, inlet check valve means communicating with said first chamber for supplying a gas thereto, said first chamber being initially supplied with a gaseous charge at a predetermined pressure, second inlet check valve means communicating with said second chamber for supplying spray material under pressure thereto, said second chamber being supplied with a charge of spray material so as to produce a pressure in said first and second chambers equal to at least twice said predetermined pressure, outlet means communicating with said second chamber for connection with airless spray gun means whereby upon operation of said spray gun means said gas will move said piston toward said second chamber forcing said spray material to said spray gun at a volume and pressure sufiicient to accomplish airless spraying without consuming the gas in said first chamber, said outlet means including a manually operable valve to control the flow of spray material therethrough, a pressure gage mounted in communication with said first chamber so as to indicate the pressure therein, said pressure gage thereby serving as a measure of the amount of spray material in said second chamber, said first head means comprising a first disc-shaped member secured within one end of said hollow cylindrical body member in a recessed position relative thereto to define a first open space within the end of said body member, said second head means comprising a second disc-shaped member secured within the other end of the body member in a recessed position relative thereto to define a second open space within the other end of the body member, said first inlet means being disposed in said first open space, and said second inlet means and said outlet means being disposed in said second open space.

4. The invention of claim 3 where said gaseous charge is initially supplied to said first chamber to a pressure of at least approximately 1000 psi. and said charge of spray material is thereafter supplied to said second chamber so as to increase the pressure in said first and second chambers to at least approximately 2000 psi.

5. In an airless spray system of a type having a vessel containing a supply of spray material, a pump for drawing spray material from said vessel and delivering the same under pressure, and at least one spray gun for producing an airless spray of said spray material when the latter is delivered to said spray gun at a predetermined pressure and volume, the improvement comprising accumulator means interposed between said pump and said spray gun and including, in combination, a hollow cylindrical body member, first head means sealing one end of said body member, second head means sealing the other end of said body member, a piston disposed within said cylindrical body member intermediate said first and second head means and longitudinally movable therein, said piston sewing to divide the interior of said body member into a first chamber between said piston and said first head means and a second chamber between said piston and said second head means, first inlet means communicating with said first chamber for supplying a gas thereto, said first chamber being filled with gas under pressure, second inlet means communicating with said second chamber and connected with 10 said pump so that spray material delivered under pressure by said pump is conducted to said second chamber, and outlet means communicating with said second chamber and connected with said spray gun whereby when said spray gun is using a greater amount of spray material than is being supplied by said pump said gas will move said piston toward said second chamber forcing said spray material to said spray gun at a volume and pressure sufiicient to accomplish airless spraying without consuming the gas in said first chamber and when said 8 pump is delivering a greater amount of spray material than is being used by said spray gun said piston will be moved toward said first chamber further compressing the gas therein so as to accumulate the excess spray material in said second chamber.

References Cited UNITED STATES PATENTS 226,731 4/1880 Eddy 222175 X 1,177,423 8/1916 La Rue 222389 X 1,630,899 5/ 1927 Lynch 222389 X 3,273,607 9/1966 ONeill 222- 389 X 3,321,110 5/1967 Price 222-389 FOREIGN PATENTS 660,710 11/ 1951 Great Britain.

SAMUEL F. COLEMAN, Primary Examiner.

HADD S. LANE, Assistant Examiner.

Images