Abstract:
A faucet is disclosed which has an outer housing formed of zinc which has a lower entry, an upper outlet, and a side cavity. There is a supply line structure extendible from the lower entry into or adjacent the side cavity, and a valve cartridge positioned in the side cavity. A plastic insulator sleeve is positioned in the side cavity between a wall of the outer housing and the valve cartridge. A brass collar is nested within the insulator sleeve and positioned outside of the valve cartridge. Hence, the advantages of a zinc outer housing are achieved while avoiding galvanic corrosion due to contact between brass and zinc surfaces. The insulator sleeve also facilitates rotational and axial alignment, and sealing.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority based on U.S. provisional application 61/176,516 filed May 8, 2009. 
     
    
     STATEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not applicable. 
       BACKGROUND OF THE INVENTION 
       [0003]    The present invention 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. 
         [0004]    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. 
         [0005]    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. 
         [0006]    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. 
         [0007]    Hence, a need exists for improved faucets which address this problem. 
       SUMMARY OF THE INVENTION 
       [0008]    In one aspect the invention provides a faucet with: 
         [0009]    (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; 
         [0010]    (b) a supply line structure extendible from the lower entry into or adjacent the side cavity; 
         [0011]    (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; 
         [0012]    (d) an insulator sleeve positioned at least partly in the side cavity between a wall of the outer housing and the valve cartridge; and 
         [0013]    (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; 
         [0014]    (f) wherein the insulator sleeve is made of a material that helps galvanically insulate the outer housing from the collar. 
         [0015]    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. 
         [0016]    Further refinements include: 
         [0017]    (a) the supply line structure defines a ridge on an exterior surface thereof; 
         [0018]    (b) the insulator sleeve defines a ledge on an interior surface and has a resilient clip; 
         [0019]    (c) the ridge can be captured between the ledge and the resilient clip to selectively couple the supply line structure to the collar; 
         [0020]    (d) the supply line structure includes external threads; 
         [0021]    (e) the collar includes internal threads that engage the external threads to couple the collar to the supply member; 
         [0022]    (f) there is a groove formed in an exterior surface of the insulator sleeve; 
         [0023]    (g) there is an o-ring seated in the groove; and 
         [0024]    (h) the o-ring can inhibit movement of the insulator sleeve within the outer housing. 
         [0025]    In other forms: 
         [0026]    (a) the insulator sleeve defines a first key; 
         [0027]    (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; 
         [0028]    (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 
         [0029]    (e) a handle is coupled to the valve stem such that the handle controls operation of the valve cartridge. 
         [0030]    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. 
         [0031]    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. 
         [0032]    The insulating sleeve also serves multiple additional valuable purposes, such as rotational and axial alignment, and assisting in the sealing function. 
         [0033]    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. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0034]      FIG. 1  is an perspective view of a faucet of the present invention which has been mounted on a conventional sink; 
           [0035]      FIG. 2  is a partial section view taken along line  2 - 2  of  FIG. 1 ; and 
           [0036]      FIG. 3  is an enlarged partial exploded view of portions of the faucet of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0037]    An example faucet  10  is shown in  FIG. 1  mounted on a conventional kitchen sink  12 . 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. 
         [0038]    Faucet  10  is in the form of a kitchen pull-out spray type faucet having a spout  14  extending upward from main outer housing  16 . There is a control handle  18  at the side of the faucet to control the flow volume and temperature of water directed out of the outer housing  16  through the spout  14 , to an associated pull-out spray head  13 . 
         [0039]    The outer housing  16  is 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 housing  16  has a lower entry  17 , an upper outlet  19 , and a side cavity  20 . The side cavity includes an inner end  22  and an outer end  24  proximate handle  18 . 
         [0040]    An insulator sleeve  26  is nested within the side cavity  20 . It has a groove  28  formed on an exterior surface  30  in which an o-ring  32  is seated. A mating groove  34  is formed in the outer housing  16  (i.e., within the side cavity  20 ) such that the o-ring  32  can be seated in both the groove  28  in the insulator sleeve  26  and the groove  34  in the outer housing  16  when the insulator sleeve  26  is nested within the side cavity  20 . This helps fix the insulator sleeve  26  in place. 
         [0041]    This insulator sleeve  26  is 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. 
         [0042]    The insulator sleeve  26  can also be keyed to the side cavity  20  such that the orientation of the insulator sleeve  26  within the side cavity  20  can also be rotationally restricted. In this regard the insulator sleeve  26  defines a pair of recesses  36  that are keyed to a pair of protrusions  38  formed within the side cavity  20  (shown best in  FIG. 3 ). 
         [0043]    Moreover, the insulator sleeve  26  may further define a ledge  40  on an interior surface  42 . A supply line structure generally  44  (e.g. the water inlet lines, and a “puck” face) has a portion located proximate to the inner end  22  of the side cavity  20  and includes a ridge  46  (shown only in  FIG. 2 ) on an exterior surface  48  which, when assembled in the side cavity  20 , engages the ledge  40  of the insulator sleeve  26 . 
         [0044]    A resilient clip  50  is formed integral with the insulator sleeve  26  and releasably captures the ridge  46  of the supply member  44  between the resilient clip  50  and the ledge  40 . Further, a series of alignment fins  52  engage mating alignment grooves (not shown) on the supply line structure  44  to orient the supply line structure  44  within the insulator sleeve  26  (and hence side cavity  20 ). 
         [0045]    With the supply line structure  44  having its terminal end generally located within or adjacent the side cavity  20 , a brass collar  54  is nested at least partially within the insulator sleeve  26  to capture a conventional valve cartridge  56 , so that an inward end of the valve cartridge abuts a terminal end of the supply line structure  44 . 
         [0046]    Note that there can also be on the supply line structure  44  external threads  58 , and that the brass collar  54  includes mating internal threads  60  that engage the external threads  58  to couple the collar  54  to the supply line structure  44  which may also be brass (therefore capturing the valve cartridge  56 ). Specifically, a neck  62  of the collar  54  proximate the outer end  24  of the side cavity  20  abuts a shoulder  64  defined by a valve body  66  of the valve cartridge  56 . 
         [0047]    A close engagement between the valve cartridge  56  and the supply line structure  44  (particularly the puck portion thereof) is desirable. To this end, the insulator sleeve  26  of the example embodiment defines a lip  68  proximate the first inner end  22  of the side cavity  20 , and the collar  54  defines an end face  70 , also proximate the inner end  22  of the side cavity  20 , such that when the collar  54  is coupled to the supply line structure  44 , a gap  72  is formed between the lip  68  and the end face  70 . 
         [0048]    As a result, the collar  54  can be sufficiently tightened to urge the valve cartridge  56  into engagement with the supply line structure  44 . An o-ring  74  seated in an annular recess  76  formed in the supply line structure  44  further helps establish a seal between the supply line structure  44  and the collar  54 . 
         [0049]    As described, the outer housing  16  has an inward surface formed of primarily zinc, and the collar  54  has 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. 
         [0050]    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. 
         [0051]    The valve body  66  of the valve cartridge  56  of the example embodiment is preferably made of plastic. With the collar  54  coupled to the supply line structure  44  (e.g., by engaging lands  78  on the neck  62  of the collar  54  with a tool and rotating the collar  54 ), an end cap  80  is engaged proximate the outer end  24  of the side cavity  20 . A valve stem  82  extends from the valve cartridge  56  and through an opening  81  the end cap  80 . 
         [0052]    The handle  18  which, in the example embedment, is made of plated or coated zinc (similar to the outer housing  16 ) includes a cavity  84  for receiving the valve stem  82  and is secured thereto by a set screw  86  oriented transverse to the valve stem  82 . As a result, movement of the handle  18  controls operation of the valve cartridge  56  and the resulting flow of water from the faucet  10 . 
         [0053]    To help secure the end cap  80  proximate the outer housing  16 , the end cap  80  defines an internal recess  88  into which an o-ring  90  is seated and the collar  54  includes a mating recess  92  that engages the o-ring  90  when the end cap  80  is engaged into the side cavity  20 . To enable the end cap  80  to mount relatively flush to the outer housing  16 , a gap  98  is established between an end face  94  of the insulator sleeve  26  (proximate the outer end  24  of the side cavity  20 ) and an end face  96  of the end cap  80  (proximate the second outer end  24  of the side cavity  20 ). The end cap  80  of the example embodiment is preferably made of plastic (e.g., acrylonitrile butadiene styrene (“ABS”)) and electroplated to provide a robust and aesthetically pleasing appearance. 
         [0054]    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. 
         [0055]    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. 
       INDUSTRIAL APPLICABILITY 
       [0056]    The invention provides faucets having an insulation structure that inhibits galvanic corrosion between two adjacent faucet parts made of dissimilar metals.