Corrosion resistant faucets with components made of different metallic materials

A faucet includes an outer housing having a surface formed of a first material. The outer housing has an entry and an outlet, and a valve cartridge is positioned at least partly in the outer housing and is configured to control flow of water to the outlet. An insulator sleeve is positioned at least partly in the outer housing between a wall of the outer housing and the valve cartridge. A collar having a surface made of a second material different from the first material is at least partly nested within the insulator sleeve outside of the valve cartridge. The insulator sleeve is made of a material that acts to galvanically insulate the outer housing from the collar.

BACKGROUND

The present application relates to faucets with an outer main housing having a surface made of one metallic composition and at least one adjacent component having a surface made of another metallic composition. More particularly it relates to structures that can avoid galvanic corrosion which could otherwise occur if the two surfaces were in contact with each other after assembly of the faucet.

A typical faucet includes an outer housing made of brass, as well as many internal brass parts. Brass is a preferred material for these purposes due to its appearance, durability, strength, machinability, and ability to support a variety of finishes. However, the material cost of brass can be high, making it desirable to find alternative materials for at least some of the larger faucet parts.

Thus, some lower cost faucets use surface materials that are primarily made of zinc for their outer housing body. However, such zinc-based surfaces are susceptible to corrosion where they contact internal brass components long term. In this regard, when a zinc-based surface is in constant contact with brass, particularly in a wet or humid environment, the differences in electrical properties between the metals can lead to galvanic corrosion.

This can undermine the structural integrity of the housing or alter its decorative appearance. While one could make all internal components of a plastic or even zinc, this would lead to other concerns such as long term reliability and/or strength.

Hence, a need exists for improved faucets which address this problem.

SUMMARY

One embodiment relates to a faucet. The faucet includes an outer housing having a surface formed of a first material, the outer housing having an entry and an outlet; a valve cartridge positioned at least partly in the outer housing and configured to control flow of water to the outlet; an insulator sleeve positioned at least partly in the outer housing between a wall of the outer housing and the valve cartridge; and a collar having a surface made of a second material different from the first material and at least partly nested within the insulator sleeve outside of the valve cartridge. The insulator sleeve is made of a material that helps galvanically insulate the outer housing from the collar.

Another embodiment relates to a faucet including an outer housing defining a bore. An insulator sleeve is received at least partly within the bore, and a collar is received at least partly within the insulator sleeve and spaced apart from the outer housing by the insulator sleeve. The collar has a first end and a second end. A valve cartridge is positioned in the collar and configured to control flow of water through the faucet, and a supply line structure is configured to receive water from a supply line and positioned at least partly in an opening in the second end of the collar.

Another embodiment relates to a faucet including an outer housing defining a cavity. An insulator sleeve is received at least partly within the cavity, and a collar is received at least partly within the insulator sleeve and spaced apart from the outer housing by the insulator sleeve. An end cap has an end face that is engaged between the outer body and the collar, and a valve cartridge is positioned in the collar and configured to control flow of water through the faucet. The valve cartridge has a valve stem extending from the valve cartridge through the end cap.

These and still other aspects will be apparent from the detailed description and drawings. What follows is a description of preferred embodiments. However, the claims should be referenced to assess the full scope of the invention.

DETAILED DESCRIPTION

Referring generally to the Figures, a faucet is shown accordingly to an exemplary embodiment. In one aspect, the faucet has:(a) an outer housing having a surface formed of a first material, the outer housing having a lower entry, an upper outlet, and a side cavity;(b) a supply line structure extendible from the lower entry into or adjacent the side cavity;(c) a valve cartridge positioned in the side cavity which is suitable to control flow from the supply line structure to the upper outlet if the supply line is supplied with water;(d) an insulator sleeve positioned at least partly in the side cavity between a wall of the outer housing and the valve cartridge; and(e) a collar having a surface made of a second material different from the first material and at least partly nested within the insulator sleeve outside of the valve cartridge;(f) wherein the insulator sleeve is made of a material that helps galvanically insulate the outer housing from the collar.

In a preferred embodiment the first and second materials are such that if they were in contact with each other, contacting surfaces of the outer housing and collar could lead to galvanic corrosion of at least one of them. In one embodiment the outer housing is primarily made of zinc, the collar is primarily made of brass, and the insulator sleeve is generally cylindrical and made of plastic.

Further refinements include:(a) the supply line structure defines a ridge on an exterior surface thereof;(b) the insulator sleeve defines a ledge on an interior surface and has a resilient clip;(c) the ridge can be captured between the ledge and the resilient clip to selectively couple the supply line structure to the collar;(d) the supply line structure includes external threads;(e) the collar includes internal threads that engage the external threads to couple the collar to the supply member;(f) there is a groove formed in an exterior surface of the insulator sleeve;(g) there is an o-ring seated in the groove; and(h) the o-ring can inhibit movement of the insulator sleeve within the outer housing.

In other forms:(a) the insulator sleeve defines a first key;(b) the side cavity defines a second key compatible with the first key such that rotation of the insulator sleeve within the outer housing can be restricted thereby;(c) there is an end cap engaged proximate an end of the side cavity, as well as a valve stem extending from the valve cartridge through the end cap; and(d) a handle is coupled to the valve stem such that the handle controls operation of the valve cartridge.

In still other forms the insulator sleeve defines a lip proximate to a first end of the side cavity, and the collar defines an end face proximate to that first end of the side cavity. When the collar is coupled to the supply line structure, a gap is formed between the lip and the end face such that the collar urges the valve cartridge into engagement with the supply member.

It should be appreciated that the present invention permits the use of a relatively inexpensive outer decorative material for the main faucet housing (such as zinc), while permitting one to continue to use the preferred brass for the collar that traps the valve cartridge. An insulating structure is provided at relatively low additional cost that avoids the galvanic corrosion which would otherwise normally occur if the brass collar were in long term contact with the outer housing.

The insulating sleeve also serves multiple additional valuable purposes, such as rotational and axial alignment, and assisting in the sealing function.

The invention provides faucets having an insulation structure that inhibits galvanic corrosion between two adjacent faucet parts made of dissimilar metals.

An example faucet10is shown inFIG. 1mounted on a conventional kitchen sink12. It should be appreciated that the term “faucet” is being used in this patent in its broadest sense to cover a wide range of plumbing fittings where water volume and/or temperature is controlled by the fitting adjacent a spout. Thus, it should be interpreted to cover kitchen or bathroom faucets, as well as tub fillers having associated control valving, shower heads having associated control valving, etc.

Faucet10is in the form of a kitchen pull-out spray type faucet having a spout14extending upward from main outer housing16. There is a control handle18at the side of the faucet to control the flow volume and temperature of water directed out of the outer housing16through the spout14, to an associated pull-out spray head13.

The outer housing16is preferably made of zinc, or a zinc alloy of 50% or more zinc. Alternatively, it could be a base material plated with such a zinc-based formulation. In any event, the outer housing16has a lower entry17, an upper outlet19, and a side cavity20. The side cavity includes an inner end22and an outer end24proximate handle18.

An insulator sleeve26is nested within the side cavity20. It has a groove28formed on an exterior surface30in which an o-ring32is seated. A mating groove34is formed in the outer housing16(i.e., within the side cavity20) such that the o-ring32can be seated in both the groove28in the insulator sleeve26and the groove34in the outer housing16when the insulator sleeve26is nested within the side cavity20. This helps fix the insulator sleeve26in place.

This insulator sleeve26is preferably generally cylindrical and made of a non-metallic material, such as plastic (e.g., NORYL brand plastic). One skilled in the art will appreciate, given the benefit of this disclosure, that a variety of other materials may be used provided they inhibit electrochemical communication and thereby reduce galvanic corrosion of various components.

The insulator sleeve26can also be keyed to the side cavity20such that the orientation of the insulator sleeve26within the side cavity20can also be rotationally restricted. In this regard the insulator sleeve26defines a pair of recesses36that are keyed to a pair of protrusions38formed within the side cavity20(shown best inFIG. 3).

Moreover, the insulator sleeve26may further define a ledge40on an interior surface42. A supply line structure generally44(e.g. the water inlet lines, and a “puck” face) has a portion located proximate to the inner end22of the side cavity20and includes a ridge46(shown only inFIG. 2) on an exterior surface48which, when assembled in the side cavity20, engages the ledge40of the insulator sleeve26.

A resilient clip50is formed integral with the insulator sleeve26and releasably captures the ridge46of the supply member44between the resilient clip50and the ledge40. Further, a series of alignment fins52engage mating alignment grooves (not shown) on the supply line structure44to orient the supply line structure44within the insulator sleeve26(and hence side cavity20).

With the supply line structure44having its terminal end generally located within or adjacent the side cavity20, a brass collar54is nested at least partially within the insulator sleeve26to capture a conventional valve cartridge56, so that an inward end of the valve cartridge abuts a terminal end of the supply line structure44.

Note that there can also be on the supply line structure44external threads58, and that the brass collar54includes mating internal threads60that engage the external threads58to couple the collar54to the supply line structure44which may also be brass (therefore capturing the valve cartridge56). Specifically, a neck62of the collar54proximate the outer end24of the side cavity20abuts a shoulder64defined by a valve body66of the valve cartridge56.

A close engagement between the valve cartridge56and the supply line structure44(particularly the puck portion thereof) is desirable. To this end, the insulator sleeve26of the example embodiment defines a lip68proximate the first inner end22of the side cavity20, and the collar54defines an end face70, also proximate the inner end22of the side cavity20, such that when the collar54is coupled to the supply line structure44, a gap72is formed between the lip68and the end face70.

As a result, the collar54can be sufficiently tightened to urge the valve cartridge56into engagement with the supply line structure44. An o-ring74seated in an annular recess76formed in the supply line structure44further helps establish a seal between the supply line structure44and the collar54.

As described, the outer housing16has an inward surface formed of primarily zinc, and the collar54has an adjacent outward surface formed of primarily brass. If they were to be in contact, galvanic corrosion would likely occur during the useful life of the faucet, particularly in a wet or humid environment like this.

However, a plastic or other galvanically insulating sleeve is provided to ensure that these parts are kept apart, yet arranges for a secure and well aligned assembly. Thus, galvanic corrosion is inhibited and the outer housing may be formed of a lower cost material without facing the corrosion concern.

The valve body66of the valve cartridge56of the example embodiment is preferably made of plastic. With the collar54coupled to the supply line structure44(e.g., by engaging lands78on the neck62of the collar54with a tool and rotating the collar54), an end cap80is engaged proximate the outer end24of the side cavity20. A valve stem82extends from the valve cartridge56and through an opening81in the end cap80.

The handle18which, in the example embedment, is made of plated or coated zinc (similar to the outer housing16) includes a cavity84for receiving the valve stem82and is secured thereto by a set screw86oriented transverse to the valve stem82. As a result, movement of the handle18controls operation of the valve cartridge56and the resulting flow of water from the faucet10.

To help secure the end cap80proximate the outer housing16, the end cap80defines an internal recess88into which an o-ring90is seated and the collar54includes a mating recess92that engages the o-ring90when the end cap80is engaged into the side cavity20. To enable the end cap80to mount relatively flush to the outer housing16, a gap98is established between an end face94of the insulator sleeve26(proximate the outer end24of the side cavity20) and an end face96of the end cap80(proximate the second outer end24of the side cavity20). The end cap80of the example embodiment is preferably made of plastic (e.g., acrylonitrile butadiene styrene (“ABS”)) and electroplated to provide a robust and aesthetically pleasing appearance.

Preferred example embodiments have been described in considerable detail, including describing the most preferred materials. However, the preferred materials and other aspects of the preferred embodiments are not intended to exemplify the full scope of the claims.

One skilled in the art, given the benefit of this disclosure, will appreciate the variety of other materials capable of use, as well as varied structures to implement these principles. Thus, many modifications and variations of the preferred example embodiments will be apparent to a person of ordinary skill in the art. Therefore, the invention should not be limited to the example embodiments described.