US1957686A - Spraying device - Google Patents

Description

May 8 1934. w. H, ANDREWS SPRAYING DEVICE Filed Feb. 26, 1950 Patented May 8, 1934 SPRAYING DEVICE William H. Andrews, Cleveland, Ohio, assigner to Irene E. Andrews Application February 26, 1930, Serial No. 431,521 '7V Claims. (Cl. 91-45) This invention relates to improvements in devices for spraying paints, lacquers or other liquids, nely divided solid particles such as insect powders, etc., and the principal object is the pro- 5 vision of such a device which is highly efficient in operation, simple and easily controlled to use a minimum amount of material and a minimum amount of pressure to secure the very best results.

This invention is an improvement in several l respects over the device disclosed in my copending application for a patent on a spraying device, led July 26, 1929, Serial Number 381,217 but the general structure herein shown is substantially the same as the structure shown in the above apl plication.

One object of the present invention is the provision of a separate and distinct passageway which communicates with the atomizer nozzle at one of its ends and with the vessel containing the material to be sprayed, at its other end. In other words, provision has been made for a passageway which serves to return some of the air pressure and the excess spraying material to the original storage vessel. Whenever, during the course of operation the atomizing nozzle chamber, becomes flooded with spraying material, said material will run back into the vessel containing the same. Moreover the issuing current of air will serve tof return some of the excess material through this passageway to the vessel referred to and also if leakage should occur.

Another object is the provision of a valve member in the suction pipe which is independent oi any other fluid regulating means in the device and which serves to regulate the capacity of the suction connection. By this means the spray head is accommodated to fluids of greater or less density or those of more or less viscous nature and also a given amount of air will fully atomize the liquid in spraying, thereby saving on the quantity oi liquid used. By use of this valve member, slow work may be readily undertaken since the liquid flow alone can be so regulated that it will not be too thin for the spraying nozzle.

Still another object is the provision of a plurality of longitudinally extending integrally cast ribs on the spray flattening member which are of such conformation as to securely engage the ejector nozzle on its surface and keep the spray flattening member spaced absolutely concentrically with the ejector nozzle. This construction was found desirable since in all prior structures, trouble developed due to the fact that the spray nattening member generally touched the ejector nozzle at one point or on one side. Consequently the air did not issue in an even ow and as a result thereof, the material being sprayed would tend to collect at this point, whereas the remaining portion of the spray would be very nearly 4 perfect. By providing these ribs, slots are formed between the ribs and the issuing air flows smoothly between them and since the spray flattening member and the ejector nozzle are held absolutely concentrioally, the issuing air and material form a perfect spray.

The invention is illustrated in the accompanying drawing in which:

Figure l represents a vertical longitudinal cross section through the device in inoperative or closed position; f

Figure 2 represents a fragmentary sectional view taken on the line 2 2 of Figure l;

Figure 3 represents a sectional view taken on the line 3-3 of Figure 1;

Figure 4 represents an enlarged view of the forward portion of Figure 1, showing the paths taken by the air and material to be sprayed; and

Figure 5 is a sectional View taken on the line 5-5 of Figure 4.

Referring now to the drawing, 1 indicates the body of the spraying device which includes the barrel portion 2 and the handle portion 3, which handle portion extends downwardly therefrom and is inclined slightly to the rear, thereby giving to the whole the appearance of an automatic rearm.

The handle portion is preferably made hollow, as indicated at 4 and has in the extreme upper portion thereof a screw threaded opening 5 adapted to be closed by a cap or spare spray nozzle 6. Furthermore, this opening aords an opportunity tc insert the valve member into the spraying device during assembly.

A spraying device of the type herein shown is employed in various industries and homes today f for spraying paints, lacquers, insect powders, various spraying liquids, insecticides, etc., and it is necessary that the material be sprayed or atomized by air under pressure. The material is 100 conveyed to the point of atomization by air pressure and it is an object of this invention to provide passageways and valve members for controlling the air pressure and the passage of the material and the mixing and atomization thereof.

To this end the body member 2 is provided with a commingler chamber or pipe '7 communicating with a passageway 8 leading to the air passageway 9 and thence to the air pressure passageway l0. The commingler chamber is situated at oneV end of a block or housing 11 and lies parallel to the air passageway 9. At the other end of the block or housing is a chamber 12 adapted to receive a coiled spring 13 which exert-s its pressure against the face of a valve 14, bearing on the seat 15. The valve 14 is provided with a stem 16, operating in a fluid tight manner in a valve stern housing 17 firmly fitted into the body member 2. The valve stem 16 projects in such a manner so that it may be given a horizontal backward and forward movement by means of the stem engaging cam surface 18 forming a part of the trigger 19 pivoted to the handle 3 at 20.

Taken broadly, the combined passageways 7, 8, 9, and may be considered as a. commingler pipe, having at one of its ends the pressure connection 10, the suction connection 21Nintermediate its ends and the discharge outlet 22 at its opposite end.

An ejector nozzle 23 is secured by means of screw threads to the body of the spraying device. This nozzle is provided with a continuous longitudinal bore through its central portion, said bore being composed of two bores of varying diameters, the outlet bore 24 being of smaller diameter than the bore 25. The bore 25 is flared outwardly at its margin for the purpose of giving a Venturi throat effect when considered in connection with the chamber 7.

Surrounding the ejector nozzle 23 and adjustably secured to the spraying device by means of screw threads is the spray flattening member or nozzle 26, forming a part of my invention. This spray attening member has two lugs 27 forwardly projecting. In the form shown, no ports are drilled through these lugs but the only opening is the central aperture. However, in the form representing the spray flattening member or spare nozzle 28 shown in the handle 3, the forwardly projecting lugs have ports 29 and 30 drilled through them. These projections have forward faces approximately at right angles to the ports extending through these projections. In the event that a different spray is desired, the spare element 28 may be substituted for the normal element 26. The element 26 has an aperture at its centre which is sufhciently larger in diameter than the forward end portion of the nozzle core to permit a hollow stream of compressed air to issue through the space thus formed. When thus issuing this hollow stream of compressed air laterally houses the stream of material issuing through the axial bore of the nozzle core so as to prevent a decided spreading of the material stream until the latter is engaged by the converging air jets issuing from the ports 29 and 30 (when the same is used) These converging air jets are well known in the art as flattening jets and their axes converge after the manner of the edges of a flattened pyramid toward the axis of the aperture whereby air jets issuing from these ports will intersect at a common point on the stream of material issuing from the ejector nozzle.

To accurately maintain the spray flattening member 26 centered with respect to the ejector nozzle 23, a plurality of ribs 31, cast integrally with the spray flattening member are provided. These ribs lie parallel to each other and are equally spaced around the inwardly projecting portion of the spray attening member. Slots are thereby formed between these ribs which slots are plainly shown as 32 in Figure 5. These ribs come in tight contact with the surface of the ejector nozzle and serve to maintain the spray ilattening member accurately centered with respect to the ejector nozzle. Therefore, the air in issuing through the slot 32 issues uniformly through the central aperture around the tip of the ejector nozzle and since the nozzles at this point at no time can come in contact with each other, drops of material cannot collect at this point. The spray of air and material issues uniformly.

Referring to Figure 4, it will be noted that a chamber 7 is formed in the block or housing 11. This chamber is preferably designated as the commingler chamber and forms a part of my invention.

The body of the spraying device has attached thereto a hose connection 33 to which an air hose may be attached and led to a suitable air compressor, not shown.

It is to be noted that the dispensing tube 34 is somewhat to one side of the container 35, which normally consists of the well known Mason jar. This jar is provided with screw threads which engage corresponding screw threads in the ange 36 provided in the body member of the device. Any form of sealing gasket 37 may be employed between the edge of the jar and the flange. The object in placing the tube 3'4 slightly to one side of the center of the jar is that experience has shown that the sprayer is used most of the time in a position in which the discharge nozzle is pointing downwardly at an angle. Consequently as the level of the material in the jar decreases, the material will tend to lie in one corner of the jar, leaving the bottom exposed in the remaining portion. Therefore, the tube will always be immersed in the material whereas, if the tube engaged the material at the center of the jar, not nearly as much of the material can be dispensed when the level in the jar decreases to a negligible quantity.

Another feature of the present invention resides in the provision of a separate passageway 38, connecting the chamber 39 with the jar 35 or the suction connection 21 by means of passageway 40. This passageway permits the return of air and spraying material to the storage vessel. In this manner, not only is air pressure exerted upon the contents of the vessel but any excess spraying material, collecting in the chamber 39 is allowed to return to the vessel for use again.

Also, another feature of this invention consists in the provision of a regulating valve 41, situated at the exit end of the suction tube whereby the quantity of material issuing through the suction tube may be regulated independent of any other regulating means in the sprayer. This valve 41 is controlled by the knurled stein 43 which is screw threaded at 42 into the body of the sprayer.

Assuming now, for an example, that the spraying device is to be used for spraying any of the well known lacquers, the material is placed in the jar and the spraying device is screwed upon the jar. The compressor is started. The operator depressesv the trigger V19, thereby causing the valve member to move longitudinally to the left and causing the air under pressure to flow from passageway 10 through passageway 9, to chamber 39, passageway 38 and passageway 40 to the jar 35. Also, the air is diverted through passageway 8, thereby creating a suction which tends to suck up the material in tube 34. Also, the air and material undergo a complete commingling in the chamber 7, prior to any atomization, and this feature is important. Intimate mixing occurs in the commingler chamber 7 and it has been found that this mixing, prior to atomization, accounts for the remarkable results achieved by this spraying device. Air issuing from the passageway 9 to the chamber 39 is caused to issue in a hollow stream from the spraying nozzle and laterally house the stream of intimately mixed material issuing through the axial bore 24 of the nozzle core, as described.

The device is composed of very few wearing parts, being made strong and capable of very severe use. An even flowing stream is assured and materials are handled with remarkable ease. The flow is under perfect trigger control and the device is well balanced, light in weight and remarkably easy to clean.

I claim:

l, A sprayer of the type described consisting of a commingler pipe having a pressure connection at one end, a suction connection intermediate the ends thereof communicating with a storage vessel, a discharge outlet at its opposite end and a separate passageway connecting said discharge outlet with said storage vessel.

2. A sprayer of the type described consisting of a conimingler pipe having a pressure connection at one end, a suction connection intermedate the ends thereof commtmicating with a storage vessel, a discharge outlet at its opposite end and a separate passageway connecting said discharge outlet with said storage vessel and valvular means controlling said pressure connection.

3. A sprayer of the type described consisting of a commingler pipe having a pressure connection at one end, a suction connection intermediate the ends thereof communicating with a storage vessel, a commingler chamber intermediate the ends thereof, an atomizer upon the opposite end, said atomizer being in communication with said storage vessel by means of a passageway other than said commingler pipe.

4. A sprayer of the type described consisting of a commingler pipe having a pressure connection at one end, a suction connection intermediate the ends thereof communicating with a storage vessel, a commingler chamber intermediate the ends thereof, an atomizer upon the opposite end, said atomizer being in communication with said storage vessel by means of a passageway other than said commingler pipe and valvular means controlling said pressure connection.

5. A sprayer of the type described consisting of a commingler pipe having a pressure connection at one end, a suction connection intermediate the ends thereof communicating with a storage vessel, a discharge outlet at its opposite end and a separate combined air and spraying material return passageway connecting said discharge outlet with said storage vessel.

6. A sprayer of the type described consisting of a commingler pipe having a pressure connection at one end, a suction connection intermediate the ends thereof communicating with a storage vessel, means to regulate the capacity of said suction connection independent of any other regulating means in said sprayer, a discharge outlet at its opposite end and a separate passageway connecting said discharge outlet with said storage vessel.

7. A sprayer of the type described consisting of a commingler pipe having a pressure connection at one end, a suction connection intermedate the ends thereof communicating with a storage vessel, means to regulate the capacity of said suction connection independent of any other regulating means in said sprayer, a discharge outlet at its opposite end and a separate passageway connecting said discharge outlet with said storage vessel and valvular means controlling said pressure connection.

WILLIAM H. ANDREWS.

Images