Automated machines are often used for cleaning dishes, utensils, kitchen items, pots and pans, etc. These automated machines, commonly called warewashing machines, are often used by commercial establishments such as restaurants. A typical warewashing machine may use an active ingredient found in a detergent, rinse aid or sanitizer.
For a sanitizer, an active ingredient, such as chlorine, may be supplied in powdered or solid block form. A warewashing machine presents an adverse environment for such powdered or solid active ingredients. Since the active ingredient must react and dissolve quickly in water used in the warewashing machine, the solid or powdered active ingredients should be formulated to easily dissolve. However, this desired ability to dissolve quickly when used is a liability while the solid or powdered active ingredient has not yet been dispensed. The very wet and high temperature environment of the warewashing machine can degrade the solid or powdered active ingredients. If such wet and/or high temperature environment should come into contact with the active ingredient before being dispensed into the warewashing machine deleterious effects may result.
A relatively large, e.g., 600 gram, solid block can be utilized with a flood-type dispenser. As the ingredient in the solid is needed, the dispenser floods the solid block for a specified period of time with water. As water floods the solid block, the solid block erodes providing an ingredient/water solution using a portion of the solid block that has been eroded. Some, perhaps much, of the solid block remains for use in subsequent cycles of the machine to which the dispenser operates. During subsequent cycles, the solid block may again be flooded with water and the process is repeated.
However, some problems exist with this arrangement. Because of variations in water temperature, more or less of the active ingredient, e.g., chlorine, can be eroded from the solid block. For example, a lower water temperature will erode less chlorine from the solid block in the predetermined period of time allotted. However, a higher water temperature will erode more chlorine from the solid block in the same predetermined period of time. Depending upon the water temperature, either too much or too little chlorine may be used to produce a desired sanitizing solution.
Other forms of active ingredient dispensers also exist in the warewashing machine environment.
Powdered detergent is typically individually manually metered or poured into the warewashing machine. This, however, results in the non-uniform dose of detergent for the warewashing machine which is highly variable based upon the person performing the manual dispensing operation. Further, it is possible that the user could come into contact with the active ingredient which could raise a safety issue.
Alternatively, a tablet of detergent may be manually placed into a warewashing machine. While placing a tablet of detergent into the warewashing machine does provide a uniform dose, this dispensing system also requires the user to handle a tablet in order to manually place the tablet into the warewashing machine.
Another technique for dispensing an ingredient is known in the industry as a blister pack. A blister pack, well known in the industry, consists of a plastic top, typically clear, formed with indentations with each indentation capable of holding an individual dose of tablet or tablets. A backing sheet is adhered over the plastic top to secure the tablets in the indentations. A user may then take the blister pack and, pushing on the plastic top at an indentation, push an individual tablet or tablets contained in an indentation through the backing sheet, perforating the backing sheet, and releasing the tablet or tablets. While this technique also provides for uniform dose, it also could allow the user to come in contact with the tablet being dispensed. Most importantly, dispensing of tablets with a blister pack is an intensely manual operation.
PCT International Publication Number WO 02/058528, Hindustan Lever Limited, Detergent Dispenser System, describes a removable cartridge for a detergent dispensing system for a dishwasher. A storage unit contains a plurality of cylindrical or spherical detergent tablets arranged in two or more rows with curved surfaces of adjacent tablets touching such that when the cartridge is upright that tablets will move under gravity towards the transfer station. The transfer station has an ejection means to eject a tablet from the transfer station through a transfer port to prevent ingress of moisture into the cartridge. The dispensing system of Hindustan recognizes the problem of moisture contamination. Hindustan attempts to have the dispensing mechanism handle all of the responsibility of preventing the moisture from contaminating the dispensing container. However, Hindustan does not solve the problem because even a little moisture or extreme humidity can then contaminate not only the tablet being dispensed but literally the whole cartridge (container) of tablets.
Some tablets being dispensed may be fragile or the active ingredient may be toxic to a user. In this case, allowing a user to contact or directly interact with solid product, including tablets, can be a significant disadvantage.
Further, some tablets and some active ingredients may contaminate the dispenser over time. Continued dispensing of multiple containers of solid product can, especially over time, cause significant contamination of the dispensing mechanism and can lead to deleterious operation including decreased reliability.