The present invention relates to devices for dispensing a chemical solution. In particular, it relates to a dispenser that forms a detergent solution from a solid cast chemical.
There is a need in industry today to provide a chemical solution that is ready to use when mixed and that is made from solid cast chemical. Solid cast chemical is essentially a chemical that is in solid form and cast in a preferably pliable, plastic container; it is effectively a bar of soap in a plastic container. Removal is typically done by dissolving the detergent in place in the container with a jet of water.
There are a number of advantages to using solid cast chemical as compared to liquid chemical. The first is safety. Since the chemical is cast inside of a container it is virtually impossible for personnel to come in contact with the chemical until it has been diluted. The U.S. Department of Transportation recognizes such chemical as safe to ship. If there is an accident, there is no liquid spillage to contaminate the ground water in the immediate area. The containers, even if cracked by the accident, retain the chemical and may simply be retrieved.
The concentration that is possible with solid cast chemical provides additional advantages. Such detergent is typically 100% active material as opposed to liquid which is between 40% and 5% active, with the remainder being water. A single capsule of solid chemical can do the same work as six to seven gallons of a typical liquid. A related advantage is the compactness of solid chemical that provides benefits when storing the chemical, shipping chemical, and when handling the chemical. The dramatic reduction in storage space is especially attractive to relatively small commercial establishments such as gas stations and fast food restaurants that have very little space to devote to storing cleaning supplies. Freight costs are also dramatically reduced since the cost of shipping water is eliminated. Other handling costs are also reduced since, for equal cleaning potential, substantially less weight and volume is being handled as compared to liquid chemical.
Another advantage of solid cast chemical is that it has an essentially indefinite shelf life. Very little can occur that can change the character of the product over time.
Solid cast chemicals are more environmentally sound than liquids. Studies have shown that “bag-in-a-box” and five gallon pail packaging of liquid chemicals actually have approximately four to five ounces of chemicals left when the package is considered empty and therefore is discarded. Raw chemicals are accordingly dumped into landfills when liquid chemical packages are discarded. Solid cast chemicals use approximately one sixth the volume of empty containers as a liquid system of equal cleaning capacity, and solid cast chemical containers are usually thoroughly rinsed of all chemical by water jet action before being discarded or recycled.
A further requirement of chemical dispensers is that the dispenser should preferably provide a ready to use solution. This requirement is a major concern for many commercial establishments. The portion of the labor pool that is utilized for cleaning functions is typically the lower skilled and less educated portion. Training of these employees is difficult and expensive. The fact that the solution is ready to use minimizes the training that is required for proper usage.
Another aspect of the training issue is that the dispenser should have a minimum number of controls and control operations necessary to obtain a container of properly mixed detergent solution. Ideally, the turning of a single valve would provide the solution.
Reliability is another desirable characteristic of a chemical dispenser. A minimum number of moving parts should be provided to minimize maintenance. The dispenser should also be small and be capable of being mounted on the wall, since the storage area for cleaning equipment in most commercial establishments is very small.
A further concern is that the chemical solution that is formed within the dispenser be isolated from the water supply, which in most cases is the water supply of the local municipality. There is considerable concern that in the event of a backup of the chemical solution in the dispenser, the chemical may be drawn into the water supply through the various plumbing that is in the dispenser. Accordingly, means must be devised to ensure that such contamination does not occur.
In the past, liquid chemical dispensers have been available that dispense a ready to use detergent solution. Additionally, solid cast chemical dispensers have been available. Drawing the concentrated chemical solution from the dispenser has proved to be a problem. When in the concentrated form, the chemical solution does not tend to flow freely and has a tendency to accumulate in the dispenser. If the solution remains in the bowl after water is turned off. The solution tends to solidify, thereby clogging the bowl
In view of the foregoing, it would be a decided advantage to have a chemical dispenser that utilizes a solid cast chemical and that can positively discharge a ready to use concentration of chemical solution. The design should provide for transporting the solution over significant distances and at heights that exceed the height of the dispenser. In order to effect this, it would be helpful if the chemical solution was forcefully expressed for use.
U.S. Pat. No. 5,846,499, owned by the assignee of the present application, in part met the aforementioned needs. Flow from the bowl of the dispenser was enhanced, but was not forcefully expressed. Flow from the dispenser could not terminate at a height higher than the height of the dispenser and the flow must terminate close to the dispenser in order to ensure that the bowl was adequately purged.
The device of the present invention substantially meets the aforementioned needs. Further, by employing an integral venturi, more solution is pulled from the dispenser than can be dispensed by gravity alone. Because the venturi forcefully ejects solution from the bowl, collection of solution in the bowl after shut off of the dispenser is minimized, thereby minimizing the possibility that retained solution plugs the outlet of the bowl. Further, the improved flow resulting from employment of the venturi minimizes bowl overflows.
Flow from the dispenser of the present invention enhances flow beyond the limits of gravity feed. The venturi enhances the mixing of the driving fluid (bypass water) and the fluid/slurry being transferred. Additionally, The forceful ejection resulting form employment of the venturi permits the discharge of the bowl to be above the height of the bowl discharge point.
The use of the venturi is effective in simplifying the design of the dispenser. In the past, separate valves were need for the respective water nozzle and the bypass water. With the present design a single valve is needed. This both reduces cost and makes training to use the dispenser simpler. A single valve puts the dispenser in operation and ceases dispenser operation.
The present invention is a venturi ejector for forcibly ejecting a slurry generated in a fluid dispenser, wherein the venturi ejector includes a venturi, the venturi being in a first flow communication with the slurry and developing a vacuum, the vacuum being in a second flow communication with atmospheric pressure, the second flow communication acting to cause the atmospheric pressure to exert a pressure on the slurry, thereby forcing the slurry to the venturi where the slurry is forcibly ejected from the venturi. A method for forcibly ejecting a slurry or solution generated in a fluid dispenser is further included.
Referring to the drawings, a fluid dispenser 10 includes housing 12, bowl 14, and water supply 16. The fluid dispenser 10 is designed to dispense a fluid or a slurry generated from a solid cast detergent. The solid cast detergent is cast in a container 20 as depicted in
Turning to the first subcomponent of the fluid dispenser 10, the housing 12 includes two major subcomponents, mounting plate 40 and removable cover 54.
Referring to
The mounting plate 40 includes a plurality of support elements 42. The first of such support elements 42 is a depending inlet support 44. An additional support element 42 is an upper support plate 46.
Two further support elements 42 are included as part of the mounting plate 40. The support elements 42 include the bottom support plate 48 and the stepped bowl support 50. The stepped bowl support 50 includes a plurality of steps 52 defined thereon.
The second major subcomponent of the housing 12 is the removable cover 54. The removable cover 54 is three sided having an open rear side 55. The removable cover 54 is designed to be readily mated to the mounting plate 40, the open rear side 55 thereby being enclosed. The housing 12 defines a generally cube shape when the mounting plate 40 and the removable cover 54 are mated. The removable cover 54 includes an upward directed bowl support aperture 56.
The removable cover 54 includes a reservoir 58 defined in the lower portion of the removable cover 54. A venturi support 60 is provided at the lowermost portion of the cover 54.
The second major subcomponent of the fluid dispenser 10 is the bowl 14, as depicted in
When installed in the cover 54, the bowl 14 is supported in part by the stepped bowl support 50 and in part by a lip 73 that rests on an edge of the bowl support aperture 56. The lower portion of the bowl 14 defines an accumulator portion 80. A nozzle support 78 is disposed within the accumulator portion 80 adjacent a downward directed flow opening 82. When installed in the cover 54, the downward directed flow opening 82 is in flow communication with the reservoir 58 defined in the cover 54.
It should be noted that an atmospheric pressure passageway 84 is defined between the inner margin of the bowl 14 and the outer margin of the neck 26 and shoulder 28 of the solid cast detergent container 20. This atmospheric pressure passageway 84 is defined circumferential to the solid cast detergent container 20 and admits atmospheric pressure to the accumulator 80 at all times.
Referring now to the water supply 16 of the fluid dispenser 10, as depicted in
Warm water flows from the inlet coupler 90 to the valve 92. Valve 92 is capable of opening or closing fluid flow from the inlet coupler 90 and thereby controls the water supply to the remainder of the water supply 16.
Valve 92 includes a valve neck 94. The valve neck 94 is support by the depending water inlet support 44 of the housing 12.
Valve 92 is fluidly coupled to uptake pipe 96. The uptake pipe 96 is capped at its upper margin with a backflow preventer 98. The backflow preventer 98 includes an air inlet 100 and preferably has an inverted cup valve 102. Water pressure in the uptake pipe 96 acts to open the cup valve 102 and a lack of pressure in the uptake pipe 96 causes air to be admitted to the backflow preventer 98 to the air inlet 100, thereby closing the valve 102 and preventing backflow from entering the uptake pipe 96 and potentially contaminating the facility water supply coupled to the water supply 16. Such backflow preventers 98 are commonly used on fluid dispensers in the prior art.
A down tube 104 is fluidly coupled to the backflow preventer 98 and to the uptake pipe 96. Down tube 104 is fluidly coupled to flow splitter 106.
Flow splitter 106 acts to effectively split the water intake flow into two different channels. The first of such channels is the nozzle supply 108 and the second is the bypass supply 110. A manually adjustable valve control 112 controls a valve (preferably, a reed valve) 114 for adjusting the split of the incoming water between the nozzle supply 108 and the bypass supply 110, as desired.
A nozzle supply tube 116 depends from the nozzle supply 108 and is fluidly connected to an upward directed nozzle 118. The upward directed nozzle 118 is designed to direct a spray of water upon the solid cast detergent within the solid cast detergent container 20 and is supported in place by the nozzle support 78 of the bowl 14.
Referring to
The venturi 125 is fluidly coupled to the distal end of the bypass flow tube 120. The venturi 125 is comprised of a restrictor 120, an inductor 128, and a receiver 130. The restrictor 120 has a transition zone 132 that has a diameter generally equal to D1 121. The transition zone 132 has a tapered inlet 134 to an interior flow passageway 136. The tapered inlet 134 acts to reduce turbulence in the flow of bypass water, thereby providing for laminar flow through the interior flow passageway 136. The interior flow passageway 136 has an interior diameter equal to D2 138. Diameter D2 138 has a lesser dimension than the restrictor diameter D1 121. Accordingly, the flow velocity of the bypass water through the interior flow passageway 136 is substantially accelerated as compared to the flow velocity of the bypass water in the bypass flow tube 120. The volume of bypass water should be at least 1.5 gpm, with an optimum flow of generally 5.5 gpm in order to generate the desired vacuum.
An exterior flow passageway 140 is defined circumferentially to the restrictor 126 between the outer margin of the restrictor 126 and the inner margin of the venturi support 60. The exterior flow passageway 140 is in flow communication with the accumulator 80 defined in the housing 12. The restrictor 126 has a mouth 137 at the terminal end thereof. The mouth 137 has a diameter D2 138. It is diameter D2 138 that defines the diameter of the column of high velocity bypass water 156 (described below) that passes through the ejector 130.
The restrictor 126 is spaced apart from the ejector 130. The inductor 128 is defined in this space between the restrictor 126 and the ejector 130. The inductor 128 is defined by the circumferential space between the restrictor 126 and the ejector 130 and by the inner margin of the venturi support 60. The inductor 128 is in flow communication with the accumulator 80 (and thereby with the reservoir 58) via the exterior flow passageway 140.
The ejector 130 is in bypass water flow communication with the inductor 128. The ejector 130 has a tapered inlet 150 that leads to an elongate flow passageway 152. The elongate flow passageway 152 has an inside diameter D3 154. D3 154 is greater than D2 138. D3 154 is greater than D2 138 by between 0.010 and 0.050 inches. Preferably, D3 154 is greater than D2 138 by generally 0.020 inches.
A column of high velocity bypass water 156 having a diameter that is substantially D2 138 emerges from the restrictor 126, passes through the inductor 128, and flows through the center portion of the elongate flow passageway 152 retaining the diameter that is substantially D2 138. The column of high velocity bypass water 156 remains in the shape of a column as it passes through the elongate flow passageway 152. Accordingly, an annular flow channel 158 is defined between the inner margin of the elongate flow passageway 152 and the outer margin of the column of high velocity bypass water 156. The annular flow channel 158 has a inner diameter that is substantially D2 138 and an outer diameter definer by the inner margin of the flow passageway 152 equal to D3 154. This annular flow channel 158 is defined between D2 138 and D3 154. The annular flow channel 158 is in flow communication with exterior flow passageway 140.
In operation, the valve 92 is opened to permit the flow of inlet water into the uptake pipe 96. The flow of inlet water proceeds to the flow splitter 106 where it is split in a selected manner between the nozzle supply 108 and the bypass supply 110. The flow in the nozzle supply 108 proceeds to the upward directed nozzle 118 wherein an upward directed spray of water is directed on the solid cast chemical exposed in the inverted detergent container 20. This spray generates a slurry solution that is comprised of the water emerging from the upward directed nozzle 118 and dissolved cast detergent from the container 20. The solution flows downward through the accumulator 80 and out the flow opening 82 and into the reservoir 58.
Simultaneously, bypass water flows through the bypass supply 110 to the venturi 125. Flow of the bypass water is accelerated by the restrictor 120 and a column of high speed bypass water shaped by flows through the inductor 128 and enters the ejector 130. The column of high velocity bypass water 156 passing through the ejector 130 generates a high vacuum in the annular flow channel 158. This high vacuum is transmitted to the reservoir 58 and the accumulator 80. Atmospheric pressure acts through the atmospheric pressure passageway 84 on the solution developed in both the accumulator 80 and the reservoir 58. The solution is forced down into the inductor 128 through the exterior flow passageway 140. The flow of solution is forced into the annular flow channel 158 where it is mixed with the column of high velocity bypass water 156 and forcibly ejected from the distal end of the ejector 130.
Typically, a hose (not shown) is clamped to the exterior margin of ejector 130 for delivery of the flow to a bucket or the like. The forcibly ejected flow from the distal end of the ejector 130 has sufficient velocity to be carried by such a hose to an elevation that is higher than the mounted elevation of the fluid dispenser 10 or the flow may be transported a significant distance in the hose. The forcible ejection from the distal end of the ejector 130 and the cleansing caused atmospheric pressure acting on the solution acts to cleanse the venturi, the reservoir 58 and the accumulator 80, thereby minimizing any solidifying of solution in the aforementioned structures and clogging such structures.