[0001] This application is related to provisional patent application Ser. No. 60/249,372 filed Nov. 17, 2000.
[0002] This invention relates to spout end devices. More specifically, this invention relates to laminar flow-type spout end devices having anti-microbial properties.
[0003] A common problem in hospitals, well known to the people responsible for infectious disease control, is the proliferation of disease-causing bacteria. Bathroom faucets are potential sites for bacterial colonization in the hospital environment because of the presence of moisture and their proximity to patients with infectious diseases.
[0004] The part of the faucet most likely to harbor dangerous microbes is the spout end device because of its relatively large wetted surface area and its exposure to air and location closest to the point of use. Because of high risk of contamination by the ambient air, spout end devices of the aerator type with vast exposed surfaces are shunned in favor of laminar flow devices with less air-exposed surfaces. However, even after flow is stopped, a few drops of water invariably remain on its laminar-forming and other surfaces, susceptible to contamination by the ambient air.
[0005] Recognition of this potential health hazard has led to the establishment of procedures in hospitals designed to sterilize the water system using high temperature water or extra doses of chlorination. However, at best, these procedures are carried out only infrequently.
[0006] The invention is a laminar-flow end device for a water spout comprising a generally cylindrical plastic component through which water passes. The component is characterized in that the plastic is molded from ingredients including a thermoplastic resin and an anti-microbial agent. The invention thus provides for continuous retardation of bacterial growth in the spout end device.
[0007] Further objects and features of the invention will be clear to those skilled in the art from a review of the following specification and drawings, all of which present a non-limiting form of the invention. In the drawings:
[0008]
[0009]
[0010] A laminar flow device is shown in an assembly in
[0011] The assembly
[0012] The laminar flow device
[0013] The flow-through volume controller element
[0014] Depending on the application, various combinations of elements are provided. As an example, flow-through volume controllers
[0015] To be able to attach mounting parts
[0016] Turning to the present invention, anti-microbial compounds exist in various forms, some employing inorganic ingredients such as silver, zinc oxide and titanium dioxide; others consisting of organic compounds such as chlorinated phenols. The common characteristic of these compounds when mixed into the plastic resin is that they create a surface condition on the finished plastic parts that retards the growth of bacteria.
[0017] Because spout end devices of most faucets are removable, anti-microbial spout end devices or components can be retrofitted into existing faucets, thereby supplementing the normal infectious disease control procedures in hospitals, for instance, and assisting in the prevention of disease.
[0018] In the process of making the component of the invention, the plastic selected, in powder form, is mixed with a suitable quantity of powder of the anti-microbial agent. Preferably, the proportions are such that the portion of the mixture which is the anti-microbial agent is no more than 5-10% of the total mixture. A larger portion may adversely affect the stability of the mixture.
[0019] The mixing should be sufficient to distribute the two powders intimately. The mixture is injected into a closed injection molding press. After setting, the mold is opened and the product ejected. Products made in accordance with the invention have the anti-microbial characteristics desired.
[0020] The anti-microbial agent preferred in the practice of the invention is the inorganic type. Specifically, an agent containing silver and zinc and a carrier of alumino-silicate is preferred and is available as “Agion” from Agion Technologies of Wakefield, Mass.
[0021] An organic anti-microbial agent may be a chlorinated phenol available under the trademark “Microban” from Microban Products Company of Charlotte N.C.
[0022] Preferably, the thermoplastic resin used with the agent in the practice of the invention is an acetal, such as “Delrin” or “Celcon”. Under the invention the mixture is used in the molding of parts
[0023] Variations in the invention are possible. Thus, while the invention has been shown in only one embodiment, it is not so limited but is of a scope defined by the following claim language which may be broadened by an extension of the right to exclude others from making, using or selling the invention as is appropriate under the doctrine of equivalents.