US2680010A - Foam dispensing device - Google Patents

Description

June 1, 1954 F. x. DUBAY FOAM DISPENSING DEVICE 2 Sheets-Sheet 1 Filed Nov. 10, 1950 INVENTOR. /7?ANK X. Due/1 Y M MW ATTOE-NEVJ June 1, 1954 F. x. DUBAY FOAM DISPENSING DEVICE 2 Sheets-Sheet 2 Filed Nov. 10, 1950 I INVENTOR. FRANK X. Dqama BY 6 WWW ATTOPNEYJ Patented June 1, 1954 UNITED STATES PATENT OFFICE FOAM DISPENSING DEVICE Frank X. Dubay, Minneapolis, Minn. Application November 10, 1950, Serial No. 195,113

Claims. 1

This invention relates to foam producing and dispensing devices and more especially to apparatus for the production of foam from detergent liquids which can be converted into stable and suitable foams only with relative difliculty. In the use of many fine detergents for cleaning operations, such as the cleaning of upholstery, removal of spots from clothing and fabrics, rugs, furs, etc., there are presently available fine detergents which have a wide variety of solvent abilities. However, for the best use of such detergents it is desirable not to apply the detergent in the liquid form because such application completely wets the fabric and may cause shrinkage and possible color running and the production of a visible ring after the cleaning operation has been carried out, and in any event complete wetting of the fabric is unnecessary. I have dis-.- covered that such detergent materials have greatest and safest usefulness when utilized in the form of the foam whereby the detergent is carried into the fabric but without excessive wetting.

1 The production of foams, however, from such diflicultly foamable materials has presented considerable diiiiculty in the art, and especially in that apparatus for producing the foam must be capable of being used by the least experienced persons, must be simple in construction and capable of being used and then set aside over long periods without deterioration before the next use.

It .is an object of the invention to provide a foam producing and dispensing device of simple character capable of foaming liquids which are relatively resistant to the production of foams usable with no harm on fabrics.

It is a further object of the invention to provide a rugged device which can be produced economically and sold widely.

It is another object of the invention to provide afoam producing and dispensing device capable of producing a dry foam of uniform character from a container at any liquid level and to evacuate all foamable liquid down to the last ounce.

It is a further object of the invention to provide a foam producing and dispensing device capable of producing a small amount of foam or a great amount of foam of uniform character or to produce a continuous or nearly continuous stream of creamy foam of substantially uniform bubble size throughout the foam.

It is another object of the invention to provide a rugged foam producing and dispensing device capable of instantaneous use after long periods of storage, yet eflicient in the production of uniform creamy foams from difiicultly foamable materials.

Other and further objects of the invention are those inherent in the apparatus herein illustrated, described and claimed.

The invention is illustrated with reference to the drawings in which corresponding numerals refer to the same parts and in which Figure l is a vertical sectional View, partly broken away to show the interior construction of the foaming device;

Figure 2 is a fragmentary enlarged view showing a modified form of one part of the foaming device;

Figure 3 is a fragmentary sectional view showing another modified form of the foaming device;

Figures 4 and 5 are fragmentary vertical views, partly in section, showing slightly modified forms of construction of the foam tube and the manner of centering the air pressure tube and mounting the squeeze bulb;

Figure 6 is a fragmentary sectional View showing a slightly modified form of bottom construction of the foaming device.

Referring to the drawings, the apparatus for production of foam includes generally a reservoir [0 in which the liquid from which a foam is produced is contained and a foaming device generally designated 2!]. The reservoir [0 is preferably a glass bottle which can be the original container in which the detergent liquid is sold. The bottle is provided with a neck at II which is provided on its exterior surface with molded threads l2 and has an internal diameter at I3 which may vary slightly, depending upon the glass blowing operation by which the bottle was made. The u per edge M of the bottle neck presents a flat surface, against which a screw type cap is adapted to bear, with an interposed gasket for closing the bottle during shipment and sale prior to use.

The. foam producing and dispensing device 20 is made of such a size that it can be inserted through the neck of the bottle and in order to hold the foam dispensing device firmly in pressure tight relation with respect to the bottle neck, there is provided a cap at 15 which has an aperture at 16. 7 Within the cap there is a gasket and supporting molding 2| of rubber or other resilient gasketing material. The member 2! has a tubular section at 22 which has an internal diameter size so as snugly to fit on the exterior portion 23 of the foam dispensing main tube. The tubular section 22 is preferably sized so that ithas to be stretched a little bit in order to slip onto the tube 23, and thereby forms a pressure tight seal with the tube. The external diameter of section 22 is such as to allow slight clearance relative to the internal diameter of the bottle neck, since such internal bottle neck diameters vary slightly in practice. The member 2| also has an outwardly extending flange at 23 which seats upon the upper edge M of the bottle neck and is held in pressure tight relationship by the cap I5 which is screwed down.

The main tube 23 of the foam dispensing device 23 is of such a length that it extends from the bottle neck to within a short distance of the bottom of the bottle in which the foarnable detergent liquid is sold and dispensed. The tube 23 is closed at the bottom by a slip on rubber cap 21 which is sized so as resiliently to grip the outer wall of the tube 23 and thereby be held in place against displacement even though pressure of several pounds per square inch is built up inside the tube 23. When in place the lower surface 28 of the cap 27 should be closely spaced relative the bottom 29 of the bottle I8. This can be accomplished by sliding the tube 23 up and down slightly in the cylindrical portion 22 of the sealing member 2|.

At the upper end of the tube 23 it is necked in at 30 and is then drawn out to a smaller diam eter at 3| so that it fits neatly against the outer surface of an inner tube 32. The tube 32 extends upwardly beyond the end 33 of the small diameter neck 3| on the outer tube 213, and the neck Si and the upper protruding end 34 of the inner tube 32-are held in pressure-tight relationship by means of a short length of plastic tubing 35 which is slipped on as illustrated. The plastic tubing deforms as shown and forms a seat on which the neck 36 of a rubber squeeze bulb generally designated 31 is adapted to he slipped and held in pressure-tight relationship due to the resilience of the neck portion 36 The rubber squeeze bulb 31 is provided with avalve at 33 so that when the bulb is squeezed air will then be forced down into the tube 32 in the direction of arrow 39.

. The lower end of the tube 32 is seated in a central pocket 28a in the bottom 28. of. cap 2! and is thereby closed and supported centrally of tube 23, or the cap 2''! may be molded with an upwardly extending protuberance centrally of the cap, shaped to extend into and thereby center the tube 32, as shown in Figure 6. Tube 32 is provided with a plurality of small drill holes at 40 at its lower end. In a preferred design in accordance with the invention, thereare provided 16 holes of No. size in the bottom one-inch length of the tube 23. In addition, the tube 32 is provided with a restricted orifice 4|, this hole being positioned so as to direct a flow of air in the direction of arrow 42 which is directly in line with the dispensing nozzle 41 that is formed on the outer surface of the main tube 23. In said preferred design hole M is No. '70 drill size. The main tube 23 is also provided with a restricted orifice at 33, this hole in said preferred design being of No. drill size and is provided with two drill holes 44 near its lower end, these holes being a No. 60 drill size in said preferred design. The hole 43 is positioned slightly below the'lower end of the tubular section 22 on the seal and the hole M is positioned slightly above the upper edge of the cap 21.

The nozzle portion 41 extends outwardly well beyond the diameter of the bottle l0 and is tipped downwardly at 45. Within the foam tube 23 and above hole 43 and below nozzle 41 there are provided a plurality of fine screens 46 which are preferably of mesh stainless steel or Monel metal. The screens 46 are preferably provided with flanges which grip either the outside of tube 32 or the inside of tube 23 or both, as shown. The screens 46 break up the bubbles and any liquid drains down tube 2-3 for re-use.

It will be appreciated, of course, that the specific sizes of the drill holes mentioned herein for a preferred design are merely illustrative. in general, it may be stated that the holes 43 and 44 considered together should be of a size such that when the air in the bulb 31 is forced downwardly into the tube 32 and thence into the" interior of the tube 23, that there will not be a suficient loss of air through holes 43 and loss of air, foam or liquid through hole 44 so as substantially to reduce the pressure within the interior of the tube 23, before the bulb 31 can again be released and another bulb full of air squeezed in. Likewise, the hole 4| and the plurality of holes 44 or slots, as in Figure 6, should form a restriction between the interior of the tube 32 and the interior of the tube 23 so that after the air is forced through the tube 32 into the interior of the tube 23 and the bulb is then released preparatory to taking in additional air for the next squeeze, the inflow of air through the hole 35 and liquid or foam through the holes cs from the interior of tube 23 should be at a substantially slower rate than the inflow of air into the bulb through the valve 38. In this way the bulb 3'! is enabled to produce a net flow of air in the direction of arrow 39 into the tube. It may be noted that the lower end of tube 32 seals against cap 21 or is sealed on the protuberance as in Figure 6.

During operation the device is assembled as shown in Figure l and usually the user starts with a full bottle of liquid which therefore establishes the liquid level in the bottle It at, for ex ample, level 50. When the foaming device 23 is first inserted into the bottle the liquid flows into the hole M in the direction of arrow 5| and air is displaced out of tube 23 through the hole 43 in the direction of arrow 52. At the same time liquid enters into tube 32 and air displaces out of hole 4| and hole 43. The net result is that the liquid level within the bottle re-establishes and fills the interior of the bottle and the interior of tubes 23 and 32 uniformly at, for. example, the level 54. When the first bulbful of air is forced downwardly by squeezing the bulb 31, the initial reaction is to force the liquid which was standing within the interior of tube 32 downwardly through the holes 40 and air is at the same time ejected through the small hole 4|, the, latter air being wasted on the first or first several squeezes. However, as the liquid is forced down through the lower end of the tube 32 and out through the holes 30, there comes a time when the liquid is all forced out and air begins to' be ejected through the holes 43 and into the interior of the tube 23 which remains filled with liquid. This air causes a foaming reaction and bubbles arise in the space between the outer surface of tube 32 and the interior of tube 23, as indicated by the arrows 55. up and fill the portion of tube 23 above the liquid level therein, but are relatively wet bubbles of foam. This upward movement of the foam isv indicated by the arrow 56.. As the foam passes through screens 33 the larger bubbles are broken up intofine bubbles and any liquid in the bubbles drains down tube 23 for re-use. When the'foam These bubbles risev and comeentirely fills the tube 23 it begins to be ejected out of the tube 41 and at this time the outflow of air through the small hole 4| injects additional air into the foam and causes it to be dried. Even at the first squeeze of bulb 3'! it is sometimes possible to generate and elevate enough foam so as to fill the tube 23 and eject some through the nozzle 41 and out through the bentdown portion 45 of the dispensing nozzle, thus forming a flow of foam at the nozzle tip as indicated by the arrows 51. A loose plug of rustproof metal wool at 48 in nozzle 45 serves to strain and unify the foam flow. When the bulb 31 has been entirely squeezed tight, the user releases the bulb. At this time there is a pressure established within the interior of tube 23 and to some extent this pressure is transferred out of the hole 43 into the space above the liquid level within the bottle II). There is, of course, some outflow of liquid through the holes 44 when the pressure in tube 23 is in excess of that within the bottle Hi. When the bulb 31 is accordingly released, there is a tendency for inflow of liquid and air from the bottle I0 through the holes 43 and 44, respectively, but since these holes are relatively restricted the flow is insuflicient appreciably to permit decrease of pressure within the tube 23. Furthermore, the pressure within the tube 23 does not immediately transfer to the interior of the tube 32 because the holes 40 are submerged in liquid and/or foam and the hole 4| is relatively small. Consequently, the tube 31 breathes in additional air freely through the flat valve 38 and the bulb 3? is then immediately squeezed again. It is possible by proper sizing of the holes 4!) and 4| to permit the filling of the bulb 3'! with a fresh charge of air before the pressure within the tube 23 has appreciably decreased, although there is always some tendency for backflow to occur through holes 40 and 4| when the bulb is released. Consequently, on the next squeeze of the bulb 3T, additional foam is produced and merges with foam already in the tube 23 and rises and is dried by additional outflow of air at the hole 4| as the foam flows through tube 41. By squeezing the bulb 31 at a rate of, for example, once every half second to once per second, a substantially continuous fiow of fine bubble foam of creamy consistency can be ejected out of the tube 45. As the device is used, the pressure within the bottle l0 tends to build up during the first few squeezes of bulb 37 and most of the pressure transfer is outwardly through the holes 43 and 44 with only a little back transfer during each release of the bulb. However, the pressure within the bottle Ill soon establishes at a pressure slightly below the peak pressure within tube 23 and thereafter the integrated action is merely for the liquid within the bottle I0 gradually to transfer inwardly through the hole 44 with consequent displacement of sufficient air out through the hole 43 to make up for the reduction of liquid level within the tube l0. As a result, by use of the instant invention it is possible to produce a uniform foam of consistent tiny bubble size and dry and almost creamy in nature, regardless of the level of the liquid in the bottle Hi and it is possible to do so even with liquids which have heretofore defied production of useful foam by use of known foam apparatus.

The instant apparatus may, if desired, be connected to a source of continuous pressure, such as an air compressor or air line, instead of the squeeze bulb 31 where the production of large quantities of foam for cleaning operations is desired, or to spare the operator the slight work of squeezing the bulb.

In Figure 2 there is illustrated another form of construction for the lower end of the tube 32. In this form the tube 32 is beaded over slightly at the bottom end 63 so as to retain in place a small plug SI of stainless steel or Monel metal wool, through which the downward fiow of air in the direction of arrow 66 is ejected. The stainless steel or Monel metal wool forms a plurality of orifices through which the air is ejected and forms the foam as indicated by the plurality of arrows 3?. This form of invention dispenses with the necessity of drilling a large number of small holes at 43, as illustrated for the principal modification.

In Figure 3 there is illustrated a slightly modified form of the invention in which the tube 23 is provided with an enlargement 23A at its upper end. This enlargement is desirable in that it provides a shoulder at 68 which-serves firmly to establish the level of the apparatus within a given size of bottle. In addition, the enlargement 23A provides a reservoir space into which the foam is forced, permitting it to drain and dry somewhat before being re-aerated by means of the air blast through the orifice 4|.

In Figures 4 and 5 there are illustrated somewhat modified forms ofconstruction of the upper end of the foam tube. In each of these figures the foam tube 23 is out off squarely at the upper end 10 and the pressure supply tube 32 is of a length such that, as in the previous modification, it protrudes slightly above the end 10 of the foam tube. In Figure 4 the pressure tube 32 is held centrally in respect to the foam tube by means of a rubber collar H which is molded so as to fit in pressure-tight relationship against the inner surface of the foam tube 23 and likewise tightly grip the outer surface of the pressure tube 32. The collar H is preferably provided with a shoulder at 12 which is of sufficient thickness so as to match the wall thickness of the tube 23, thus presenting ,a smooth surface when the two are placed together. The collar H is terminated at the level 13-43 and to the portion of tube 23 which protrudes outwardly above this level there is attached the neck 18 of the squeeze bulb I5. By providing a chamfered surface at 14 in the collar H a very neat connection is thereby provided.

In Figure 5 the same effect is achieved by molding the squeeze bulb T5 with an integral collar portion 16 which serves thereby centrally to locate the tube 33 within the foam tube 23. By molding the two parts in one, it is also possible to provide a very smooth curve at l! which adds to the appearance of the device.

Figure 6 shows a slightly modified form of con struction for the bottom end of the foaming device. In this figure the cap is molded with a central protuberance on stub 81 which fits into and plugs and thereby centers the lower end of tube 32. In place of a plurality of drill holes 40 as in Figure 1, there are provided one or more slots 82 which permit the air to blow out. The bubbles are formed and are further formed and/or strained and broken up by a wrapping of rustless metal wool 83 which fills the space with foam tube 23 around tube 32 for a short distance in the bottom to the level 84-84 which is above the top of the slots 82. Two apertures 44 in the wall of foam tube 23 enable the liquid that is to be foamed to enter into the interior of tube 23 and rise throug the metal wool 83 and into tube 23. This construction is economical to build and produces an excellent uniformity of foam.

As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is-to'be understood that I do not limit myself to thespecific embodiments herein.

What I claim is:

1. An article of manufacture comprising a reservoir having a top opening, a foam tube closed'across the bottom, said foam tube extend ing downwardly from said opening to adjacent the bottom of the reservoir, means for mechanicallysupporting the upper end of said foam tube in pressure tight relation in respect to the reservoir at said opening, a spout on the outside of the reservoir, said spout being connected to the upper end of said foam tube for delivering foam therefrom, a pressure tube extending from outside the reservoir and then down to adjacent the bottom of the foam tube and terminating at its lower end ingas dispersing nozzle'means within the foam tube, pressure means outside the reservoir having an outlet connected in pressure tight relation to the pressure tube for generating pressure therein, means mechanically supporting the thus connected pressure means adjacent the top opening of the reservoir, the upper part of the foam-tube and the pressure tube above the spout being connected in pressure tight relationship, said foam tube within the reservoir being closed in respect to the reservoir except for a small openingat a low position near the bottom of the foam tube and another small opening adjacent the top of the foam tube and screen means extending across the'foam tube slightly above the small opening adjacent the top of the foam tube but below the connection of the spout thereto.

2. An article of manufacture asset forth in claim 1 wherein the upper part of the foam tube above the spout and thepart of the pressure tube adjacent theretoare connected in pressure-tight relationship by a resilient fitting closing the space between said tubes.

3. The apparatus of claim lfurther characterized in that the pressure means is a squeeze-bulb having a check-valved inlet.

4. The apparatus of claim 3 further characterized in that the squeeze bulb pressure means is positioned so that it will drain through its outlet into said pressure tube.

' 5. An article of manufacture comprising a foam tube closed across the bottom, said foam tube being positioned generally upright and having an upper and a lower end, a spout connected.

to said foam tube adjacent the upper end thereof for delivering foam therefrom, a pressure tube positioned Within said foam tube and extending from a point adjacent the upper end of said foam tube to a point adjacent the lower end thereof, said pressure tube terminating at its lower end in a dispersing nozzle means positioned within said foam tube, pressure means having an outlet connected in pressure tight'relation to said pressure tube for generating pressure therein, the

upper part of said foam tube above said spout being connected in pressure tight relation to the portion of said pressure tube adjacent thereto, said foam tube having a small opening at a lower position near the bottom thereof and another small opening adjacent the top of the foam tube and screen means extending across the foam tube slightly above the small opening adjacent the top of the foam tube but below the connection of the spout thereto.

References Cited in the file of this patent UNITED STATES PATENTS

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