1. Field of the Invention
This invention relates to fluid handling processes and apparatus. More particularly, this invention relates to a fluidic nozzle for use with low-pressure, trigger spray applicators that can offer spray patterns heretofore unachievable with present applicators.
2. Description of the Related Art
Generally, a trigger dispenser of the type involved here is a relatively low-cost pump device which is held in the hand and which has a trigger operable by squeezing or pulling the fingers of the hand to pump liquid from a container and through a nozzle at the front of the dispenser. See
Such dispensers may have a variety of features that have become common and well known in the industry. For example, the dispenser may be a dedicated sprayer that produces a defined spray pattern for the liquid as it is dispensed from the nozzle. It is also known to provide adjustable spray patterns so that with a single dispenser the user may select a spray pattern that is in the form of either a stream or a circular spray of liquid droplets.
Many substances are currently sold and marketed in containers with trigger sprayers. Examples of such substances include window cleaning solutions, carpet cleaners, spot removers, personal care products, assorted cleaning products, weed control and pest control products, and many other materials for other general spraying uses.
Such dispensers usually comprise a bottle that includes a spray head attached thereto. The spray head typically includes a manual pump that is actuated by the hand of a user to dispense the particular liquid product in a spray or stream or foam to a desired surface location or in a desired direction. The operating pressures of such manual pumps are generally in the range of 30-40 psi. The nozzles for such dispensers are typically of the one-piece molded “cap” variety, with channels corresponding to either the offered spray or stream patterns that line up with the feed channel coming out of a sprayer assembly.
Deficiencies of such applicators include: (a) the relative lack of control of the spray patterns generated, (b) the frequent generation in such sprays of an appreciable number of very small diameter or fine droplets which often are conveyed into the surrounding environment and may be harmful if inhaled, and (c) a tendency of the resulting spray patterns to be such that they are prone to have areas of heavier liquid coverage which, when the targeted surface is vertically oriented, results in the sprayed liquid collecting and forming pools that have undesirable, break-out portions that stream down the sprayed surface.
Sprayer heads recently have been introduced into the marketplace which have battery operated pumps in which one has to only press the trigger once to initiate a pumping action that continues until pressure is released on the trigger. These typically operate at lower pressures in the range of 5-15 psi. They also suffer from the same deficiencies as noted for manual pumps; plus, appear to have even less variety in or control of the spray patterns that can be generated due to their lower operating pressures.
Despite much prior art relating to trigger spray applicators, there still exists a need for further technological improvements in the ability of such applicators to control their spray patterns, especially for those applicators that employ the lower-operating pressure, battery powered pumps.
3. Objects and Advantages
There has been summarized above, rather broadly, the prior art that is related to the present invention in order that the context of the present invention may be better understood and appreciated. In this regard, it is instructive to also consider the objects and advantages of the present invention.
It is an object of the present invention to provide new, improved nozzles for trigger spray applicators that offer more variety in and control of the spray patterns that can be generated by such applicators.
It is another object of the present invention to provide new and improved nozzles for trigger spray applicators of the type that employ battery-operated pumps.
It is yet another object of the present invention to provide new and improved nozzles for trigger spray applicators that can reduce the percentage of fine droplets generated in the sprays of such applicators.
It is also an object of the present invention to provide a means for reducing the “streaming” problems which result when present trigger spray applicators are sprayed onto vertical surfaces.
It is another object of the present invention to introduce the use of fluidic inserts and fluidic oscillators into trigger spray applications.
These and other objects and advantages of the present invention will become readily apparent as the invention is better understood by reference to the accompanying summary, drawings and the detailed description that follows.
Recognizing the need for the development of improved nozzles for trigger spray applicators, the present invention is generally directed to satisfying the needs set forth above and overcoming the disadvantages identified with prior art devices and methods.
In accordance with the present invention, a fluidic nozzle, for use with a trigger spray applicator that issues a desired spray pattern of fluid droplets, and wherein the applicator has a liquid delivering orifice and an exterior surface proximate the orifice that is configured to receive a spray nozzle, includes in a first preferred embodiment a member having a front and a rear surface and a passage that extends between these surfaces, wherein a portion of this passage is configured in the form of a fluidic circuit, and the configuration of this fluidic circuit is chosen so as to provide the desired spray pattern. Additionally, the passage's rear portion may be configured so as to allow this member to fit on that portion of the spray head which is configured to receive a spray nozzle.
In a second preferred embodiment, an upstream portion of this fluidic nozzle's passage may include an expansion section portion which has an orifice that connects this expansion section with the surrounding environment so as to allow a liquid flowing through this passage to entrain the gaseous environment surrounding the member into the passage. When the liquid is a soap-like solution, it is found that a foam is generated that can effectively be sprayed by such a fluidic nozzle.
In a third preferred embodiment, it proves useful to construct this member as two distinct parts. The front portion of this member becomes a fluidic insert which has a fluidic circuit molded into its passage. The rear portion of this member becomes a housing whose front face has a cavity into which the fluidic insert part can be fitted.
In a fourth preferred embodiment, the order of the parts mentioned in the third preferred embodiment is reversed. The front portion of the member becomes a housing having a rear cavity. The rear portion of the member becomes a fluidic insert which has a fluidic circuit molded into its passage. This fluidic insert part is then fitted into the housing's rear cavity.
Thus, there has been summarized above, rather broadly, the present invention in order that the detailed description that follows may be better understood and appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims to this invention.
Before explaining at least one embodiment of the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways.
Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. For example, the discussion herein below generally relates to liquid spray techniques; however, it should be apparent that the inventive concepts described herein are applicable also to the dispersal of other fluids, including gases, fluidized solid particles, etc.
The present invention involves methods and apparatus for creating and controlling various spray patterns from low-pressure, battery-powered trigger spray applicators.
To improve upon the performance of this trigger spray applicator, one needs to replace the current nozzle 4 with one that is compatible with the front face 2a or mounting surface of the current spray head's housing 2 and which also provides such a sprayer with the desired improved operating performance.
To understand how fluidic nozzles can achieve such performance improvements, it proves useful to review what we mean when we speak of “fluidic inserts or oscillators.”
A “fluidic insert or oscillator” is a component part in a liquid spray device that can, without any moving parts, be designed to yield any one of a wide range of oscillating sprays (i.e., as compared to the relatively steady state flows that are emitted from standard spray nozzles) in which the liquid droplets that comprise the sprays can, by engineering of the “insert,” be given desired physical properties (e.g., size of the droplets, the spatial distribution of the droplets as they pass through a plane situated normal to the centerline which marks the spray's direction of flow). See
“Fluidic inserts” are generally constructed in the form of a thin, rectangular member that is molded or fabricated from plastic and has an especially-designed liquid flow channel fabricated into either its broader top or bottom surface, and sometimes both—assuming that this fluidic insert is to be inserted into the cavity of a housing whose inner walls are configured to form a liquid-tight seal around the insert and form an outside wall for the insert's boundary surface/s which contain the especially designed flow channels. Pressurized liquid enters such an insert and is sprayed from it.
Although it is often more practical from a manufacturing standpoint to construct these inserts as thin rectangular members with flow channels in their top or bottom surfaces, it should be recognized that they can be constructed so that their especially-designed flow channels are placed practically anywhere within the member's body; in such instances the insert would have a clearly defined channel inlet and outlet.
The especially-designed liquid flow channels that are fabricated into such “inserts” are known as “fluidic circuits.” Such circuits are designed to create the flow phenomena within their paths that will yield the desired spray having specified physical properties for its droplets. There are many well known designs of fluidic circuits that are suitable for use with fluidic inserts. Examples of such circuits may be found in many patents, including U.S. Pat. No. 3,185,166 (Horton & Bowles), U.S. Pat. No. 3,563,462 (Bauer), U.S. Pat. No. 4,052,002 (Stouffer & Bray), U.S. Pat. No. 4,151,955 (Stouffer), U.S. Pat. No. 4,157,161 (Bauer), U.S. Pat. No. 4,231,519 (Stouffer), which was reissued as RE 33,158, U.S. Pat. No. 4,508,267 (Stouffer), U.S. Pat. No. 5,035,361 (Stouffer), U.S. Pat. No. 5,213,269 (Srinath), U.S. Pat. No. 5,971,301 (Stouffer), U.S. Pat. No. 6,186,409 (Srinath) and U.S. Pat. No. 6,253,782 (Raghu).
To show how such fluidic inserts can be sued to improve the performance of spray applicators, we show in
This passage 14 is seen to have a front 14a and a rear 14b portion with a wall that effectively separates such portions. The wall has at least one orifice 15a. The passage's front portion 14a is configured into a cavity 20 that allows for the front-loading, press-fit insertion of a spray controlling, fluidic insert 22.
This situation is better shown in
These flow paths 24, 26, 28 are alternately aligned with the front housing's orifice 6 by rotating the housing 12 about the spray head housing's front face 2a on which it is press-fitted.
There exist many well-known-in-the-art designs for these flow paths or fluidic circuits 24, 26, 28 so as to enable them to deliver different types of spray patterns. Most of these contain various elements (e.g., inlet, power nozzle, interaction chamber, throat, expansion section, outlet) in the paths to generate specific desired spray patterns. All of these fluidic circuit designs are considered to be within the disclosure of the present invention.
Additionally, it is recognized that such flow paths 24, 26, 28 can be molded into this insert 22 in many different, obvious ways other than that shown herein. These other obvious ways (e.g., top and bottom centered paths and one or more paths on any of the insert's four edges) are also considered to be within the scope of the disclosure for the present invention.
Some of the fluidic circuits that have been found to be most effective in this first embodiment are shown from a top-view perspective in
To see how such an insert 22 in conjunction with the housing 12 of the present invention can yield a variety of spray patterns, see
Rotating this assembly 90 degrees clockwise keeps this flow path aligned the spray head's orifice so as to yield a vertical, two-dimensional spray pattern. See
A further 90 degree rotation of the housing 12 aligns the insert's flow path 46 with the 3D fluidic circuit 42 with the orifice 6 so as to yield a stream of liquid that exits from the assembly. See
Another 90 degree rotation of the housing 12 aligns the insert's 3D fluidic circuit 42 with the orifice 6 so as to yield a fully three-dimensional spray pattern. See
This assembly or member 10 again consists of a housing 12 which has a passage 14 that extends along its centerline between its front 16 and rear 18 surfaces. This passage 14 is seen to have a front 14a and a rear 14b portion in which the front portion of the passage takes the form of an element of the insert's fluidic circuit (i.e., a throat and an expansion section). The passage's rear portion 14b is configured into a cavity 20 that allows for the rear-loading, press-fit insertion of the fluidic insert 22.
The more complicatedly-designed insert 22 of this embodiment is seen to have a front 22a and a rear 22b portion and a wall 22c that separates them. Its front portion has a fluidic circuit molded into both its top 22d and bottom 22e flat-faced surfaces. The upstream portions of both of these circuits connect to an orifice 22f, 22g which goes through the wall 22c and connects with a cavity 21 that is configured into the insert's rear portion 22b. As we've seen in earlier embodiments, the shape of this cavity 21 and the insert's rear surface 23, along with possibly the housing's rear surface 18, will usually be configured so as to allow for mating with the front face 2a of the spray head onto which the assembly 10 is to be fitted.
It was previously mentioned that these fluidic nozzles for spray applicators will often be called upon to spray substances that include window cleaning solutions, carpet cleaners, other general cleaning products, etc. It was in experimenting with various fluidic circuits to spray such soap-like solutions (i.e., detergent containing) so as to overcome the previously mentioned “streaming problems” that we discovered a somewhat surprising finding—fluidic circuits work very well to spray foams.
This was unexpected since it had previously been found that almost all of the known fluidic circuits could not effectively spray mixtures of liquids and air (two phase flows). This was thought to be the case because the vortices that are typically formed in such circuits to induce oscillations in the sprays are no longer formed with the expected regularity or work as effectively because of the air pockets that exist in such two phase flows. However, we found that when the air is effectively trapped in small amounts throughout the foam that our fluidic circuits behaved as expected.
The technology for creating a foam while spraying a soap-like solution is well known. One creates at a point upstream of the spray nozzle an expansion section in the liquid's flow passage. An orifice is then added in this expansion section which connects with the surrounding atmosphere. This allows the flowing soap-like solution to entrain air through the orifice and this air is then mixed with the solution as it flows downstream so as to create a foam which is then sprayed from the nozzle.
Shown in
As previously indicated, the air engine 48 has a passage 50 that connects its front 52 and rear 54 faces. At a point in this passage there is an expansion section 56 that provides for a rapid increase in the diameter of the passage. Proximate this section is an orifice 58 that connects this passage with the engine's exterior surface. Aligned with this orifice is a comparable orifice 60 in the housing which connects the cavity in which the engine is situated to the surrounding gaseous atmosphere. These orifices allow a liquid flowing thru the engine to entrain air through the orifices and to subsequently mix it with the liquid that flows thru the assembly 10. When this liquid is a soap-like solution, it mixes with the air to create a foam which is then sprayed from the fluidic insert 22.
It should be recognized that all of the fluidic nozzle embodiments previously shown can, like that shown in
Although the foregoing disclosure relates to preferred embodiments of the invention, it is understood that these details have been given for the purposes of clarification only. Various changes and modifications of the invention will be apparent, to one having ordinary skill in the art, without departing from the spirit and scope of the invention as it will eventually be set forth in claims for the present invention.
This application claims the benefit of Provisional Patent Application No. 60/612,742, filed Sep. 24, 2004 by Russell Hester, Rosa Korobkov, Alan Santamarina and Keith Schloer. The teachings of this application are incorporated herein by reference to the extent that they do not conflict with the teaching herein.
Number | Date | Country | |
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60612742 | Sep 2004 | US |