US 3319834 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
y 1967 E. STEELE 3,319,834
SPRAY TANK WITH HEATING MEANS FOR SPRAY FLUID Filed Oct. 5, 1965 Turn I .1 k gr 6 u E 52 g :02 u 54% 5 4B INVENTOR IRVIN E. STEELE ATTORNEYS United States Patent 0 3,319,834 SPRAY TANK WITH HEATING MEANS FOR SPRAY FLUID Irvin E. Steele, 1004 Houghton St., Connersville, Ind. 47331 Filed Oct. 5, 1965, Ser. No. 493,167 12 Claims. (Cl. 222-146) This invention relates to a novel tank construction, and more particularly to an all purpose tank particularly adapted for use as a spray tank, especially for spraying paints and similar liquids under pressure.
Paint sprayers have been known for many years and have long been used in commercial applications for the purposes of painting automobiles, machine parts and the like. One of the outstanding characteristics of sprayed on paint is the smoothness of the finish which, if properly done, exhibits none of the brush stroke or roller marks of a brushed or rolled on surface. More recently, smaller portable paint sprayers have been finding wider usage in the nonindustrial markets for a wide variety of purposes.
However, always attendant to the use of a pressurized spray device is the danger of physical harm which may result from careless usage or inadvertent loosening and removal of covers, caps or the like, while the contents of the container are still under pressure. For this reason, most pressurized containers incorporate certain safety features, such as an extra locking device or latch for the container coupler, in an attempt to insure that the cover will not be inadvertently blown off the container during disassembly so as to injure the operator. Even the small pressurized tanks commonly used by home owners to dispense garden sprays are customarily provided with a safety latch or other cover protector designed to minimize accidents, which usually result from the operator forgetting to de-pressurize the container after the job is finished and before he loosens the container cover. This problem is particularly aggravated in the larger commercial type sprayer, where the liquid to be sprayed may be under a gaseous pressure of several atmospheres.
For the most part, the safety devices for the covers or tops of pressurized containers have taken the forms of yokes or safety bars and in order to safely attach both the cover and the yoke, there are usually provided several brackets. Thus, each time the container is to be opened, several brackets must be loosened and the process then repeated when the container is to be reclosed. While adequate from the safety standpoint, these prior constructions do not provide optimum convenience to the operator and necessitate an undue amount of manipula- F tion, hence loss of operating time, particularly during the emptying and refilling process.
Other disadvantages of known constructions include the requirement that in the larger commercial type units, the liquid to be sprayed often requires mechanical agitation in order to maintain proper viscosity of the liquid in the container, and hence the accompanying cost and complexity of a motive power system for an agitator drive.
The novel pressurized fluid container of the present invention avoids the above-mentioned and other difliculties by providing a container assembly which may be readily opened and closed by simply unthreading a small cap in the unit, releasing a safety arm and then removing the entire container top. This provides optimum convenience to the operator while at the same time retaining all the safety features of the known constructions tending to eliminate inadvertent accidents in use of the container. In addition, a novel air supply tube in conjunction with a slanted bottom wall in the container provides pressurized gas agitation of the liquid within the container so that no mechanical agitator is necessary in using the device with most sprayable liquids. A further important feature of the present invention involves the provision of a novel valving system for the container including a steam chamber beneath the slanted container bottom so as to provide a simple and efficient arrangement for supplying a heating fluid directly to the liquid to be sprayed. The provision of a spray hose connection at the extreme lower portion of the pressurized liquid compartment assures complete run-off of the sprayed liquid.
In the container of the present invention the container top simply slips over in sealing engagement with a reinforced annular ring at the top of the container. The top is secured to the body of the container by means of a simple threaded cap provided with a nipple for attachment to an air line supplying air or other pressurized fluid to the liquid within the container. In addition, a safety device in the form of a safety arm having a central annular ring is readily slipped over the top retaining cap and locked to opposite sides of the container so as to insure that the top will not be inadvertently blown off in the event that the retaining cap is removed while the liquid compartment is under pressure. A combination air vent valve and filler cap assembly is provided in the container top for venting the contents of the container to atmosphere and for filling the container with liquid to be sprayed in the event the operator does not wish to remove the entire top of the container. A plurality of heating fluid supply inlets are provided in the container wall and communicate with the steam chamber at the bottom of the container suitably vented by a condensation drain cock so that adequate heating fluid may be supplied to the liquid contents of the container in optimum heat exchange relationship with the liquid so as to provide adequate heating to the desired temperature.
It is therefore one object of the present invention to provide a novel container for pressurized fluids.
Another object of the present invention is to provide an improved and novel spray tank.
Another object of the present invention is to provide a spray tank particularly adapted for use in spraying paint and similar liquids.
Another object of the present invention is to provide a novel spray container or tank having improved safety features in conjunction with a readily attachable and removable container top.
Another object of the present invention is to provide a spray container requiring no mechanical agitator and having improved venting and heating fluid portions therein for venting the contents to atmosphere, for filling the tank, and for heating the contents of the tank to the desired temperature.
These and further objects and advantages of the invention will be more apparent upon reference to the following specification, claims and appended drawings wherein:
FIGURE 1 is a vertical cross section through the novel spray tank of the present invention;
FIGURE 2 is a top plan view of the spray tank of FIGURE 1;
FIGURE 3 is a horizontal section through the tank taken along line 3-3 of FIGURE 1; and
FIGURE 4 is a partial vertical section through the container top taken along line 4-4 of FIGURE 2.
Referring to the drawings, the spray tank or container of the present invention generally indicated at 10 in FIG- URE 1 comprises a body 12 consisting of a circular tank bottom 14 and annular side wall 16. The tank elements are preferably all formed of stainless steel, the preferred thickness for the tank being in the order of from 9 to 10 gauge, i.e. nominal thickness of from 0.1495 to 0.1340 inch.
In addition to tank bottom 14, the container is provided with a slanted bottom 18 defining a tapered space between plates 14 and 18 hereinafter referred to as a steam chamber. Communicating with the steam chamber 20 are three angularly spaced steam connections 22, 24 and 26, which as best seen in FIGURE 3, are welded as at 28 or otherwise suitably secured to the wall 16. By means of these connections which pass through the wall 16 and communicate with the interior of steam chamber 20, a suitable heating fluid such as steam or the like may be supplied to the underside of slanted plate 18 so as to pass heat through this plate to the liquid-air compartment 30 forming the major portion of the tank interior. Bottom wall 14 is provided with a condensation drain cock 32 so that condensed steam or other heating fluid in the liquid phase may be periodically drained from the steam chamber 20. Adjacent the lower end 34 of slanted plate 18, where it meets bottom plate 14, the liquid and air compartment 30 communicates with a spray hose connection 36 passing through tank wall 16 and likewise, preferably welded to the tank wall as indicated at 38. This connection is adapted to receive a spray hose by means of which the liquid spray under gaseous pressure passes outwardly of the compartment 30 and is applied to the object to be sprayed, for example the part or article to be painted.
Passing through plates 14 and 18 and secured thereto as by welding at 42 and 44 is a central clamp rod which passes through the center of both steam chamber 20 and air and liquid compartment 30. The upper end of clamp rod 40 is drilled out as at 46 to provide a passageway for air or other pressure gas which passageway communicates with the hollow interior 48 of an L- shaped air tube 50 having a short integral, horizontal section 52 welded to clamp rod 40 as at 54 and an elongated vertical section 56 joined to horizontal section 52 by an integral bend or elbow 58. Section 56 of air tube 50 is slightly spaced from but runs parallel to the central clamping rod 40 and terminates at its lower end in an outlet 60 spaced slightly above the slanted plate 18 and lying in a radial plane extending from the central clamping rod 40 to the air hose or spray outlet connection 36. In this way, incoming pressurized gas (preferably air) passes from the outlet 60 of the air pipe into the lowermost portion of paint compartment 30 where is serves to agitate and mix the paint or other spray liquid and for most liquids obviates the necessity for a separate mechanical agitator. Due to the slanted nature of plate 18, the remaining liquid (when chamber 30 becomes almost empty) runs down this plate to collect adjacent outlet connection 36 so that the tank may be substantially completely emptied of liquid and no unused liquid remains in the tank at the end of a spraying operation.
In the preferred embodiment, the upper end of the tank 12 is provided with an annular reinforcing rib 62 illustrated in FIGURE 1, Which is suitably secured to tank wall 16 and whose upper edge lies in the same horizontal plane as the upper edge of the tank wall. Closing off the upper end of the tank and completely enclosing compartment 30 in conjunction with the tank body 12 is a top or cover 64 provided with an annular groove 66 adjacent its outer edge, which groove slidably receives the upper edges of the tank wall 16 and the reinforcing rib 62. Preferably received in groove 66 is an annular gasket or seal 68 so that when the cover 64 is tightly secured to the tank body the tank is adequately sealed against escape of liquid or gas from the compartment 30. Cover 64 is preferably of dish-shaped construction, as illustrated in the drawings and is provided with a central downwardly extending boss 70 having a central aperture 72 through which passes the upper end of clamp rod 40. The upper end of clamp rod 40 is threaded as illustrated at 74 in FIGURE 4, which threads are adapted to mate with similar internal threads on a cup-shaped cap 76. Threaded into the base 78 of cap 76 is an air pipe nipple 80.
This nipple is also provided with external threads 82 at its other end as illustrated in FIGURE 1 for coupling to an air hose connector 84 on the end of a flexible air supply line or hose 86. Threaded cap 76 is preferably provided with an annular sealing gasket 88 shown in FIGURE 4 to seal the cap to the upper end of clamp rod 40.
Threaded through cover or top 64 is a second nipple 90 which similarly receives as best seen in FIGURE 4 a second internally threaded cup-shaped cap 92 secured to the threaded upper end 94 of nipple 90. This cap is similarly provided with a sealing gasket 96 and the cap receives in its base the threaded end of a connector 98 for establishing fluid communication from the interior of compartment 30 through nipple 90 to a globe valve 100. By manually opening globe valve 100, the interior of compartment 30 may be exhausted to atmosphere so that the compartment may be depressurized when it is desired to remove the cover 64. Similarly by unthreading cap 92 from nipple 90, the chamber may be refilled with paint or other spray liquid or other materials may be added to the spray already in the chamber without the necessity for unlocking and removing cover 64.
Welded as at 102 and 104 to diametrically opposite sides of the tank wall 16 near its upper end are a pair of U-shaped brackets 106 and 108. Passing through leftmost bracket 106 as best seen in FIGURES 1 and 2 is a bolt 110 secured to the bracket by a nut 112. Similarly a pin 114 having an integral head 116 passes through the rightmost bracket 108. Preferably welded at one end to the head 116 of pin 114 and at its other end to the tank wall 16 is a short retaining chain 118.
Surrounding the cap 76 but spaced therefrom is an annular bar or ring 120 having welded thereto as at 122 and 124 in FIGURE 2, a pair of locking bars 126 and 128. The combined ring and rigidly joined and 0ppositely extending bars 126 and 128 form a safety arm for cover 64, and the bars are provided at each end with depending ears 130 and 132 suitably apertured to respectively receive the bolt 110 and the pin 114. These ears pass between the spaced legs of the brackets 106 and 108 and are locked to the brackets by the bolt and pin. If it is desired to not completely remove the safety arm but at the same time separate the cover from the body of the container, the pin 114 may be simply knocked out from bracket 108 and the safety arm pivoted at its left hand end in FIGURES 1 and 2 about the bolt 116 clear of the top so that the top 64 may be removed from the container. For this reason, central ring 120 preferably is provided with a sufiicient diameter to clear the top of clamp rod 40 when the locking cap 76 is removed.
In operation, the container is first filled with the liquid to be sprayed such as paint, pesticide, or any other suitable spray material, and then the cover 64 is slid over the upper end of clamp rod 40 with the annular groove 66 received over the upper end of the container wall 16. In order to clamp the cover to the container body and to seal it against leakage, cap 76 is then tightly threaded onto clamping rod 40 and tightened over threads 76 such that the cap 76 bears against the upper end of cover boss 70 to tightly clamp the cover to the container body. The relatively large diameter of safety ring 120 provides clearance for the gap 76 so that it may be threaded to the rod with the safety bar previously locked in place (before attachment of cap 76) by means of the bolt 110 and pin 114. Once both the safety bar and then the cap are attached, the container compartment 30 is pressurized by a suitable gas, preferably air under pressure, supplied by a suitable source (not shown) to the compartment 30 by way of hose 86, clamp rod 40, and air pipe 50. The spray material is expelled through outlet coupling 36 by way of a conventional spray hose and valve operated nozzle (not shown), If it is desired to maintain the paint or other material to be sprayed 'at an elevated temperature, steam from a suitable source may be supplied by way of appropriate steam lines to the steam inlet fixtures 22, 24 and 26 so as to fill the steam chamber 60. Heat is readily transferred to the liquid in compartment 30 through the relatively broad heat transfer surfaces afforded by the slanted bottom plate 18 and this coupled with the agitation of the liquid in the container under the incoming air pressure from air pipe 56 assures that the liquid will be maintained at an appropriate viscosity for ready dispersion during the spraying operation. Condensed steam in chamber may be periodically removed by opening the drain cock valve 32.
Once spraying is completed, globe valve 100 is manually opened exhausting compartment 50 to atmosphere and relieving the pressure within the container. If, during the operation, it is desired to add additional contents to the compartment 30, this may be done by then removing cap 92 and inserting additional materials through the hollow nipple 90. Cap 92 is then rethreaded onto the nipple to seal the compartment, globe valve 100 is closed, and the compartment repressurized.
After spraying has been completed, globe valve 160 is again opened to depressurize the container. This assures that none of the elements such as the cap 76, cap 92, or cover 64 will be blown off of the container when the device is being disassembled. Subsequent to depressurization, the cap 76 may be removed, thus releasing cover 64. In the event that the system is not completely depressurized at this time, the cover 64 still cannot be blown off from the body of the tank by any pressure remaining in the system due to the fact that the cover is still retained on the body by the safety arm comprising ring 120 and arms 126 and 128. With cap 76 removed and valve 100 open, the system is completely depressurized and the safety arm may be pivoted to the left in FIGURE 1 about bolt 110 by knocking out pin 114 and releasing the right hand end of the safety bar. It is, of course, apparent that the diameter of ring 120 can be made sufficiently large to clear the cap 76 so that the safety bar may be attached and removed independently of the cap. How ever, it is preferred that the safety bar be constructed so that it must remain over the cover until the locking cap 76 is removed. This provides an added safety feature to the system. Inadvertent loss or misplacement of pin 114 is avoided by providing chain 118 secured to the side wall of the tank so that the pin will always be available during reassembly of the unit.
It is apparent from the above that the present invention provides an improved general purpose tank particularly suited for use as a spray tank for spraying almost any type of liquid or dispersible material. Important features of the present invention include the provision of a novel safety device to protect the operator from injury, while at the same time providing for the attachment and removal of the tank cover with a minimum of time and effort. A slanted bottom wall assures that the liquid compartment will always be substantially completely exhausted of liquid without requiring that the tank be tilted or otherwise unnecessarily moved about by the operator. This slanted bottom in conjunction with an inlet air pipe feeding pressurized gas to the tank adjacent the outlet fitting 36 provides for increased agitation of the liquid in the container under the influence of the incoming pressurized gas and in most instances makes it possible to spray liquids without the necessity for providing a separate mechanical agitator. Finally, a readily detachable system is provided in the cover for depressurizing the system to atmosphere either before or after complete exhaustion of the liquid compartment. Beneath the liquid compartment and in good heat exchange relationship therewith is a novel steam chamber making it possible to supply heating fluids to the tank to heat the sprayed liquid before it passes out through the outlet fitting.
The tank of the present invention may be constructed from a variety of materials, and in a variety of thicknesses depending upon the contemplated pressures it must with stand in usage. Stainless steel is preferred for the various structural portions of the container and by way of example only, the container wall, top and bottom plates may be formed of 9 or 10 gauge stainless steel which provides adequate strength for most operating pressures. Similarly, the particular size of the tank may be varied in accordance with usage. It is possible to use the tank either as illustrated in FIGURE 1 or in conjunction with rollers or a suitable dolly upon which the tank is supported so that it may be readily moved about to the desired position. If provided in small portable sizes, a suitable handle may be attached to the top plate or to the safety bar so that the tank may be carried by hand.
The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
What is claimed and desired to be secured by United States Letters Patent is:
1. A container comprising a tank having a body portion including a slanted bottom, a top for said tank body, a fluid outlet coupling in said tank body adjacent the lowermost portion of said slanted bottom, said tank top having an aperture therein, a clamping rod secured at one end to said tank bottom and passing outwardly of said tank through said aperture in said tank top, said clamping rod having a fluid passageway in its other end, means coupled to said clamping rod for directing incoming fluid from said passageway onto said tank bottom adjacent said fluid outlet coupling, and a cap having a fluid inlet coupling removably attachable to said clamping rod for establishing inlet fluid communication to said passageway and for clamping said top to said tank body.
2. A container according to claim 1 including a safety bar pivoted to one side of said tank body, said safety bar being removably attachable to the other side of said tank body in a position to overlie said tank top.
3. A container according to claim 2 wherein said safety bar comprises a central ring surrounding said cap and a pair of outwardly extending arms each terminating in a downwardly extending ear, and means for releasably attaching each of said ears to said tank body.
4. A spray container comprising a tank having a cylindrical side wall, a slanted bottom, and a removable top, said top including a central aperture, a spray outlet in said side wall adjacent the lowermost portion of said slanted bottom, said bottom, top and side wall defining a fluid compartment, a clamping rod rigidly secured at one end to said bottom with its other end slidable through said aperture in said top, said other end of said clamping rod projecting outwardly of said top when said top is assembled to the remainder of said tank, said other end of said clamping rod including an inlet passageway for pressurized gas, a gas tube coupled to said clamping rod for directing incoming pressurized gas downwardly onto said slanted bottom at a location adjacent said spray outlet, said gas tube lying in a radial plane containing said clamping rod and said spray outlet, and a cap threadable over said projecting portion of said clamping rod to clamp said top to the side wall of said tank, said cap including a gas coupling for supplying gas under pressure to said inlet passageway.
5. A container according to claim 4 wherein said top includes a combination filler opening and air vent, a closure cap therefor, and manually operable valve means mounted on said closure cap for venting the contents of said tank to ambient pressure.
6. A container according to claim 4 including a safety bar overlying said top and fastened to opposite sides of said tank Wall.
7. A container according to claim 4 including a heating fluid chamber beneath said tank bottom.
8. A spray container comprising a tank having a cylindrical side wall, a slanted bottom, and a removable top, said top including a central aperture, a spray outlet in said side wall adjacent the lowermost portion of said slanted bottom, said bottom, top and side walls defining a fluid compartment, a clamping rod rigidly secured at one end to said bottom with its other end slidable through said aperture in said top, said other end of said clamping rod projecting outwardly of said top when said top is assembled to the remainder of said tank, said other end of said clamping rod including an inlet passageway for pressurized gas, a gas tube coupled to said clamping rod for directing incoming pressurized gas downwardly onto said slanted bottom at a location adjacent said spray outlet, said gas tube lying in a radial plane containing said clamping rod and said spray outlet, said other end of said clamping rod projecting outwardly from said top being threaded, a cap threadable over said projecting portion of said clamping rod to clamp said top to the side wall of said tank, said cap including a gas coupling for supplying gas under pressure to said inlet passageway, a safety bar overlying said top and comprising a central ring surrounding said cap, a pair of radial arms secured to said ring and each terminating in a downwardly extending ear, a U- shaped bracket on opposite sides of said tank wall, a bolt pivoting one of said ears to the legs of one of said brackets, and a sliding pin releasably coupling the other ear to the other of said brackets.
9. A container according to claim 8 including a retaining chain coupling said sliding pin to said tank wall.
10. A container according to claim 8 including a fluidtight heating chamber beneath said bottom wall, a plurality of angularly spaced heating fluid inlets communicating with said chamber, and a drain cock coupled to the bottom of said chamber.
11. A container according to claim 8 wherein said tank is formed of stainless steel.
12. A container comprising a tank having bottom and side walls and a removable top, a fluid outlet in one wall of said container adjacent its bottom, said top having an aperture therethrough, a clamping rod rigidly secured to one of said walls and passing through said aperture, said clamping rod having a fluid inlet passageway therein, a cap removably attachable to said clamping rod for clamping said top to the remainder of said tank, said cap being provided with a fluid inlet coupling for establishing inlet fluid communication with said passageway in said clamping rod, and a safety bar secured to the opposite sides of said container and extending over said top, said safety bar having a ring surrounding said cap.
References Cited by the Examiner UNITED STATES PATENTS 105,933 8/1870 Fowler 222394 277,855 5/1883 Taber -169 590,993 10/1897 Lochmann 222146 X 904,371 11/1908 Stewart 222-394 1,109,828 9/1914 Goff 22057 X 2,120,297 6/1938 Reinecke 222-4007 X 2,199,065 4/1940 Bell. 2,224,741 12/1940 Metrick et a1. 222394 2,584,551 2/1952 Chambers et a1. 2,621,830 12/1952 Stow et a1. 222-4007 X 3,135,438 6/1964 WeX et al. 22057 X RAPHAEL M. LUPO, Primary Examiner.