1. Field of the Invention
This invention relates generally to a method, apparatus and system for accurately measuring and calibrating liquid components dispensed from a dispenser, and more particularly for accurately measuring and calibrating the dispensing of a liquid product.
2. Description of Prior Art
Many cleaning and sanitizing processes, whether laundering, warewashing or the like, have as a significant portion of their operating costs the expense of the formulated aqueous products they use. Furthermore, the effectiveness of most, if not all, cleaning and sanitizing processes is inextricably linked to supplying a calibrated or measured amount of a formulated aqueous product to the process. Too little product use can impair the effectiveness of a cleaning and/or sanitizing process. Too much product use can result in significant waste and adds unnecessary operating expenses to a business. For example, hospitality businesses such as hotels, hospitals, restaurants, and the like use liquid detergents and cleaning solutions for laundry and warewashing. These processes require proper formulation of the solutions to prevent waste and increase the effectiveness of the cleaning and sanitizing process. To achieve these objectives, many efforts have been made to calibrate, control and measure the dilution and delivery of concentrated liquid products. These processes vary from, on one hand, simply manually measuring and mixing to utilizing a computer-controlled dilution device. One common dilution mode involves utilizing a dispensing device that combines, under mixing conditions, a flow of concentrate and then a flow of diluent. The flow of liquid diluent can be directed through an aspirator such that, as the diluent passes through the aspirator, a negative pressure arises inside the aspirator drawing the liquid concentrate into the aspirator to mix with the liquid diluent. Both Copeland, et al., U.S. Pat. No. 5,033,649 and Freese, U.S. Pat. No. 4,817,825 and Mehus, et al., U.S. Pat. No. 5,915,592 disclose dispensers having aspirators for diluting liquid concentrates to produce liquid products in this general way. Such aspirator-type dispensers have been used for diluting and dispensing a liquid concentrate.
In a number of applications, there is a desire to supply a certain amount of liquid concentrate. In using a timing mechanism wherein the aqueous diluent is used for a certain amount of time, various amounts of concentrate may be dispensed depending upon the pressure of the liquid diluent and/or the viscosity of the liquid concentrate.
Given the range in viscosity of varying formulated liquid products, and the change that can result in viscosity due to the conditions uncontrollable by the manufacturer, such as temperature of the use location and pressure of the aqueous diluent used for dispensing, problems can and do occur that result in too little or too much product being dispensed. Even situations may arise where no product is dispensed as a result of the product source being empty or the dispenser malfunctioning without notice to an operator. There are numerous parameters and conditions that affect the dilution of liquid products that are dispensed by an aspirating dispenser.
The present invention addresses these problems and provides for a method, apparatus and system for accurately measuring and calibrating liquid components dispensed from a dispenser independent of the viscosity of the aqueous liquid product or the pressure of the source of the liquid diluent.
In addition, the present invention addresses the real-time monitoring of product dispensing, including the rate, volume and calibration of the product being dispensed to insure the liquid product is accurately measured and dispensed.
In one embodiment, the invention is a method for accurately measuring and calibrating liquid components dispensed from a dispenser. The method includes providing an aspirator having a plurality of liquid inlet ports and an outlet port so that each liquid inlet port receives a liquid component. A liquid component is passed through a flow meter and into the aspirator. An amount of the liquid component being introduced into the aspirator is measured with the flow meter, and the liquid component is dispensed from the outlet port of the aspirator.
In another embodiment, the invention is an apparatus for accurately measuring and calibrating liquid components dispensed from a dispenser. The apparatus has an aspirator having a plurality of liquid inlet ports and a liquid outlet port, whereby each liquid inlet port is in communication with a liquid source. A flow meter is connected in liquid communication to at least one of the liquid inlet ports. The flow meter includes an inlet connected to receive liquid from a liquid source and an outlet connected in liquid communication to a liquid inlet port of the aspirator. The flow meter is for measuring an amount of liquid being introduced into the aspirator from a liquid source. The flow meter is also connected in liquid communication to a liquid product source and the outlet is connected in liquid communication to a valve and to a liquid inlet port of the aspirator. The amount of liquid measured by the flow meter is the amount of liquid product aspirated into the aspirator from a liquid product source.
In another embodiment, the invention is a dispensing system for accurately measuring and calibrating dispensing of a liquid component. The system has an aspirator having a plurality of liquid inlet ports and an outlet port. Each liquid inlet port is for receiving a liquid component from a liquid source. A flow meter is connected in liquid communication to at least one of the liquid inlet ports in the aspirator to measure an amount of the liquid component being introduced into the aspirator. A valve is connected in liquid communication to a liquid source and a liquid inlet port of the aspirator. A controller is connected in electronic communication to the flow meter and the valve. The controller is configured to receive the measured amount from the flow meter and issue an instruction to the valve for actuating between open and closed positions based on the measured amount.
While the specification concludes with the claims particularly pointing out and distinctly claiming the invention, it is believed that the present invention will be better understood from the following description taken in conjunction with the accompanying drawings, in which:
Referring to the drawings, wherein like numerals represent like parts throughout the several views, there is generally disclosed at 10 a dispensing apparatus. The dispensing apparatus 10 includes an aspirator assembly 12. The aspirator assembly 12 includes an aspirator and four solenoid valves 28-31 (solenoid valve 31 not shown). The aspirator also includes a diluent inlet port 16 in fluid communication with passageway 24 within the body 22 of aspirator 14 shown in
Each product inlet port 18-21 of aspirator 14 is connected in fluid communication to flow meters 36 and 42 (and two not shown) via a product conduit. The flow meter is in-turn connected in fluid communication to a product container 43 and 50 (and two not shown) via a product conduit. Product conduits 32-35 illustrated in
While the previously described dispensing assembly 10 is preferred to be used with the present invention, it is understood that other suitable assemblies may also be used in combination with the dispensing apparatus 10 of the present invention. Referring to
Referring to
Referring to
In operation, a liquid, such a liquid diluent, is communicated from a liquid or diluent source 54 through intake conduit 52. A suitable water solenoid valve 56 is placed in the flow path of the intake conduit 52 and is utilized to open and close the flow of water through the intake conduit 52.
The boost pump 56 raises the pressure of the water from the source pressure from the pressure associated with source 54 to an elevated pressure. In one aspect of the invention the boost pump raises the pressure of liquid diluent from the source pressure to a suitable elevated pressure. Liquid diluent is communicated through the boost pump 56 through a conduit to an anti-siphon valve 64 such as an atmospheric pressure breaker which is commercially known and available. The diluent liquid is communicated from the anti-siphon valve 64 through conduit 66 into the aspirator assembly 12 by way of diluent inlet port 16. Then, by a suitable controller, not shown, one of the solenoid valves 28-31 is activated thereby placing the respective product inlet port 18-21 in communication with passageway 24 in aspirator body 22 illustrated in
Flow meters 36, 37, 39 and 42 continually monitor and calculate an amount, such as a volumetric amount, of the liquid product 80 being drawn from a product containers 48-51. In one aspect of the invention, a solenoid valve 28-31 is actuated so that the aspirator draws liquid product 80 from one of the liquid product containers 48-51 in through a flow meters 36, 37, 39 and 42. When the requested amount, such as the requested volume of liquid product, has been drawn into the aspirator 14, the solenoid valve 28-31 closes. The liquid product and liquid diluent are dispensed from the aspirator body 22 through outlet port 26 to the requesting end-use process via outlet conduit 68.
In the present invention, because flow meters 36, 37, 39 and 42 measure the volume of liquid product 80 being drawn into the aspirator 14, changes in the viscosity of the liquid product 80, pressure of the liquid diluent or other parameters related to aspirated dispensing do not affect the end volumetric amount that is dispensed through the aspirator. In the present invention, the source pressure or pressure of the liquid diluent entering the aspirator 14 may also vary. For example, the present invention contemplates a dispensing apparatus without a boost pump that operates using the source pressure of the liquid diluent from the source 54. Variations in the pressure of the liquid diluent passing through the aspirator 14 are compensated by the flow meters 36, 37, 39 and 42, which measures the exact volume of liquid product being dispensed regardless of changes in the pressure of the liquid diluent being used to draw the liquid product into the aspirator and dispense out the outlet port 26. For example, if the pressure of the liquid diluent passing through the aspirator 14 drops, the amount of liquid product 80 being drawn from a product container will also decrease, and thereby such dispensing cannot be time-based. With the present invention, a pressure drop in the liquid diluent source pressure does not result in a change in the end amount of liquid product being dispensed as the solenoid valve 28-31 is opened and closed according to information received from the flow meters 36, 37, 39 and 42. When the flow meters 36, 37, 39 and 42 indicate that the requested amount of liquid product has been dispensed, the flow meter then provides an instruction to a controller (not shown) which in turn closes the solenoid valve 28-31 to discontinue dispensing liquid product. In the case where the dispensing apparatus 10 malfunctions, such as where one of the flow meters malfunctions, the dispensing apparatus 10 may operate on a time-based dispensing process. This will allow the dispensing apparatus 10 to dispense at least some liquid product until the malfunction can be remedied.
The above-noted invention may be used for products that include softeners, neutralizers, starch, alkali, chlorine-bleach, or detergent.
Referring now to
While the figures illustrate the use of flow meters 36, 37, 39 and 42 in the flow path of product conduits 32-35, it is understood that a flow meter may also be placed in the flow path of conduit 66 to measure the amount, such as the volumetric flow, of liquid diluent being introduced into the aspirator 14 from liquid diluent source 54. In this manner, dispensing apparatus 10 is able to monitor the specific amount of liquid diluent being introduced into the aspirator 14 and the specific amount of liquid product being drawn product containers thereby knowing the specific amount of both products being dispensed to the laundry machine 76. These or other suitable connections may be utilized to incorporate the dispensing apparatus 10 of the present invention into a dispensing system utilizing a use solution.
The above specification, examples and data provide a complete description of the manufacture and use of the composition of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.