Abstract:
An internally threaded split nut having an arcuate gap defining an opening large enough to pass over the outside diameter of a first tubular conduit or elongate rod section from the side, the split nut then being coaxially alignable and threadedly engageable with a cooperatively second threaded conduit or rod section having an outside diameter greater than that of the first section. Use of the subject split nut to releasably secure a water supply valve assembly having a REHAU® hose barb fitting to a wall of an in-wall appliance outlet box is also disclosed.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates to a split nut, and more particularly, to a split nut that facilitates attachment of a valve assembly to an in-wall outlet box of the type used with appliances such as washing machines, ice makers, and the like. The invention is particularly useful where the valve assembly includes a REHAU® PEX hose barb fitting that is pre-attached to the valve inlet. 
   2. Description of Related Art 
   In a conventional in-wall outlet box installation for household appliances, at least one water supply valve, preferably a quarter-turn ball valve, is used to provide a controllable flow of potable water to the appliance. Such water supply valves typically have a downwardly extending nipple with a male pipe thread that is inserted through an aperture in the bottom wall of the molded plastic outlet box, after which a nut is threaded upwardly onto the nipple and tightened until it contacts the underside of the bottom wall and securely attaches the ball valve to the outlet box. 
   In recent years, cross-linked polyethylene (“PEX”) tubing has become popular for use as water supply lines to inlet valves for appliances such as washing machines, ice makers and the like. Such tubing is typically attached to the bottom of the inlet valve assembly by means of an EVERLOC® PEX hose fitting (“REHAU fitting”) marketed by REHAU Incorporated, Leesburg, Va. Until now, the REHAU fitting that has been used when installing outlet boxes has a smooth-walled tubular section at one end and a hose barb at the other. The smooth end and the hose barb end of the fitting are typically separated by a radially extending flange having an outside diameter (“OD”) significantly greater than the OD of either the smooth or hose barb sections. The flange serves as an anchor point for a tool that is used to crimp the PEX tubing to the hose barb. However, because the OD of the flange for a REHAU hose barb fitting of a given nominal diameter (e.g., ½ inch) is larger than the inside diameter (“ID”) of a nut attachable to the male threads of a valve nipple having the same nominal diameter, the nut cannot be passed over the flange to attach the valve assembly to the outlet box if the REHAU fitting and valve nipple are connected prior to attachment of the valve to the outlet box. Therefore, it has been necessary for an installer first to attach the valve to the outlet box using a standard nut, and then to sweat the smooth end above the flange of a REHAU fitting into the bottom of the valve nipple. 
   A device and procedure are therefore needed that will enable a REHAU hose barb fitting to be manufactured as part of, or to be preattached to, a water supply valve assembly in such manner that the valve assembly can still be attached to an in-wall appliance outlet box by threading a nut into contact with a wall of the box. 
   Prior art patents disclose “split nuts” that typically have two opposed, internally threaded sections that are hinged or otherwise clamped together to form a circumferentially extending nut that can be quickly installed or released from an externally threaded bolt or shaft. Other patents disclose “split rings” and “snap rings” that are typically single-piece, substantially circular rings having a relatively small arcuate gap that can be widened by flexing the ring slightly during installation or removal. Although they are not typically threaded, split rings or snap rings may have spaced-apart tangs extending either radially inward or outward to prevent them from being displaced axially along the cylindrical shaft or conduit to which they are applied. 
   U.S. Pat. No. 6,799,930 discloses a spring-biased, quick-release nut. U.S. Pat. No. 6,460,901 discloses a split thread nut assembly for coupling a flanged pipe to a threaded pipe. U.S. Pat. No. 6,402,206 discloses a split ring with inwardly facing bosses that is used in a fitting for plastic tubing. U.S. Pat. No. 6,352,439 discloses a two-part connector for use in electrical junction boxes. The connector comprises an externally threaded portion that can be threaded into a box, and a spring steel snap ring that fits over the threads to hold the connector in the box and resist pull-out forces. U.S. Pat. Nos. 5,836,627, D387,971 and 5,538,299 disclose split nut locking devices, especially for support rods for auto hatchbacks. U.S. Pat. Nos. 5,000,640; 4,274,323; 2,676,509; 1,652,169; 1,366,884 and 1,082,993 all disclose internally threaded split nuts comprising at least two opposed sections that cooperate to define a nut providing full 360° coverage around an externally threaded pipe or bolt. Different mechanisms are provided for holding the two halves together. 
   SUMMARY OF THE INVENTION 
   The internally threaded split nut of the invention is preferred for use in installations: (1) where it cannot be conveniently threaded onto a structure having otherwise-cooperating male threads; and (2) where there is a smaller-diameter section adjacent to the male-threaded structure that has an OD sufficiently less than the ID of the split nut that the split nut can be translated laterally to a position disposed around the smaller-diameter section and in coaxial alignment with the male-threaded structure, and then threaded onto the male-threaded structure. The split nut must have an arcuate gap that is large enough to permit lateral translational movement of the split nut past the OD of the smaller-diameter section into a position that is coaxially aligned with the male-threaded structure. However, the arcuate gap must also be small enough that the split nut will remain threadedly engaged with the male-threaded structure during subsequent use. 
   Although many other uses of the split nut of the invention will become apparent to those of skill in the art upon reading this disclosure, a preferred use of the invention is for attaching water supply valve assemblies to in-wall mounted outlet boxes. The split nut of the invention is disclosed herein in relation to a particularly preferred use for securing quarter-turn valves to a wall of an outlet box for washing machines, ice makers, or other similar appliances. 
   Applicants have discovered that the attachment of a water supply valve assembly to an in-wall appliance outlet box is most easily achieved through use of an internally threaded, one-piece split nut as disclosed herein that can be translated laterally from a direction transverse to the major longitudinal axis of the valve assembly into coaxial alignment with a smaller-diameter section of a tubular section disposed above the flange of a hose barb fitting, preferably a hose barb fitting made by REHAU Incorporated, identified above. In this situation, the outside diameter of the split nut is typically greater than the OD of the aperture in the outlet box, which is in turn greater than the OD of the flange portion of the hose barb fitting. 
   Once the split nut is positioned so that it is coaxially aligned with an adjacent, externally threaded nipple section of the valve assembly, the split nut is then threaded onto the male threaded section to releasably secure the valve assembly to the outlet box. One preferred split nut of the invention comprises an arcuate gap in its perimeter having substantially parallel sides that define an opening about 0.015 in. greater than the OD of an unthreaded, tubular section around which it is to be applied. 
   By using the subject split nut, it is possible to insert the nipple of a water supply valve assembly having a hose barb fitting already attached to the end of the nipple opposite the valve through an aperture in an outlet box wall and then slide the split nut around the tubular section from the side and into coaxial alignment with the valve nipple above the flange of the hose barb fitting. The split nut can then be threaded onto the nipple to secure the valve to the outlet box wall. It will be appreciated, however, that the invention disclosed herein can be similarly utilized with cooperatively threaded sections of other structures, such as rods or bolts, that do not have tubular cross-sections but have adjacent or proximally disposed unthreaded sections having an OD slightly smaller than the ID of the associated split nut. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The apparatus of the invention is further described and explained in relation to the following drawings wherein: 
       FIG. 1  is a front elevation view of an appliance outlet box suitable for in-wall mounting having two water supply valves with REHAU hose barb fittings mounted to the bottom wall of the outlet box using the split nuts of the invention; 
       FIG. 2  is an enlarged side elevation view, partially broken away and partially in cross-section, illustrating the manner in which the split nut of the invention is applied to a different water supply valve assembly during installation of the valve assembly to the bottom wall of an outlet box; 
       FIG. 3  is an enlarged perspective view, depicting a preferred embodiment of the split nut of the invention; 
       FIG. 4  is a top plan view of the split nut of  FIG. 3 ; and 
       FIG. 5  is an enlarged cross-sectional elevation view taken along line  5 - 5  of  FIG. 4 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   As used in this description, the term “split nut” refers to internally threaded nut  10 , as further described below, which has a gap in a side wall that permits the nut to be moved laterally into a position where it can be threaded onto an externally threaded structure. The split nut of the invention can be made of metal, in which case it is substantially rigid, or of a polymeric material that is more flexible, although flexing of the split nut to increase the size of the gap is not required for use of the invention. 
   Referring to  FIG. 1 , split nut  10  is shown in a preferred use for releasably securing quarter-turn valve assemblies  18  to bottom wall  22  of an appliance outlet box  12  suitable for in-wall installation, particularly outlet boxes for washing machines or ice makers. Each valve assembly  18  comprises a side-mounted handle to facilitate the use of a water hammer arrester  19  disposed above each valve assembly. Each valve assembly  18  has a hose barb fitting  20 , preferably of the type marketed by REHAU Incorporated, with a flange disposed between the hose barb and the valve. In-wall outlet box  12  is typically made of molded plastic and is preferably provided with brackets  14 ,  16  for the attachment of straps (not shown) or other similarly effective means that can be secured to studs by nails or other fastening devices when mounting outlet box  12  in a stud bay of a wall. Hose barb fittings  20  are desirably provided for use in connecting PEX water supply lines to each of valve assemblies  18 . 
   Referring to  FIG. 2 , water supply valve assembly  21  is shown in relation to bottom wall  22  of outlet box  12  prior to the attachment of split nut  10 . In this view, valve assembly  21  is a quarter-turn ball valve without a water hammer arrester and with a handle disposed on top of the valve rather than at the side as shown in  FIG. 1 . Hose barb fitting  20  and externally threaded section  32  (“nipple  32 ”) of the valve are unitarily formed (as shown) or integrally connected as part of valve assembly  21 . Hose barb fitting  20  preferably further comprises hose barb section  24  and smooth-wall tubular section  26  with annular flange  30  disposed therebetween. Internal bores  36  of hose barb section  20  and  38  of nipple  32  preferably cooperate to supply fluid, typically potable water, to the inlet side of valve assembly  21 . Nut  10  preferably comprises an annular sidewall including hexagonal head  42  and skirt  40 , internal threads  46  and a gap  50  in the sidewall defined by walls  48  as shown in  FIGS. 3-4 . Valve assembly  21  is preferably attached to outlet box  12  by inserting barbed hose fitting  20  and nipple section  32  through aperture  46  in bottom wall  22  of outlet box  12 , then moving nut  10  laterally into coaxial alignment with smooth-wall section  26  of hose barb fitting  20 , and finally, threading nut  10  onto cooperatively threaded nipple  32  until skirt  40  of nut  10  snugly engages the underside of bottom wall  22  of outlet box  12  as shown by dashed outline in  FIG. 2 . Valve assembly  21  is preferably formed primarily of brass to resist corrosion when contacted with chlorine-containing potable water, and nut  10  is preferably made of die cast zinc. It will be appreciated, however, that nut  10  can also be made of other metals, or made from a durable polymeric material suitable for the intended application. 
   The OD of nipple section  32  and hose barb fitting  20  is desirably slightly less than the ID of aperture  46  through bottom wall  22  of outlet box  12  to permit insertion of those unitary (or pre-attached) portions of valve assembly  21  downwardly through aperture  46  prior to the application of nut  10  to externally threaded nipple  32 . The OD of annular flange  30  is greater than the ID of nut  10 , preventing nut  10  from being passed upwardly over flange  30  prior to threading nut  10  into engagement with external threads  34  of nipple  32 . According to published IAPMO standards, the OD of a Rehau flange for a nominal ½ inch PEX connection is 0.840 inches minimum, with no maximum specified. The OD for the valve thread on nipple  32  (assuming a nominal ½ inch NPSM (straight pipe thread)) is 0.813 to 0.823 inches. The ID of the associated split nut  10  is 0.747 to 0.749 inches. The OD of smooth-wall section  26  of hose barb fitting  20  is less than the OD of nipple  32 , and the ID of nut  10  is desirably greater than the OD of smooth-wall section  26 . This permits nut  10  to be moved laterally to a position where nut  10  is coaxially aligned with bore  36  of smooth-wall tubular section  26  above annular flange  30  of hose barb fitting  20 , provided that the minimum distance between gap walls  48  is also greater than the OD of smooth-wall section  26 . 
   Although smaller-diameter section  26  is referred to as a “smooth-wall section” in the context of this preferred embodiment, it will be understood by those of ordinary skill in the art upon reading this disclosure that split nut  10  is similarly useful for engaging threads  34  to releasably secure valve assembly  21  to outlet box  12  no matter what the external configuration of the section adjacent to the externally threaded section, provided that the maximum transverse dimension of the adjacent section is less than the ID of nut  10  and provided that the axial distance between threads  34  and the “blocking structure,” in this case annular flange  30 , is sufficient to permit nut  10  to be inserted laterally therebetween. 
   A preferred structure for split nut  10  of the invention is further described in relation to  FIGS. 3-5 . Nut  10  preferably comprises skirt  40 , hexagonal head  42 , a plurality of wrench flats  52  disposed around head  42 , internal threads  44  and arcuate gap  50  defined by walls  48 . Walls  48  are preferably substantially parallel, although parallel walls  48  are not required for the invention. Walls  48  define a gap  50  through the sidewall of split nut  10  that is sufficiently large to receive smooth-wall tubular section  26  between them, but sufficiently small that nut  10  can securely engage external threads  34  of nipple  32  without falling away from them or loosening unintentionally once the threads are engaged and split nut  10  is tightened. Split nut  10  thereby securely holds valve assembly  21  in a fixed positional relationship to outlet box  12  until nut  10  is loosened around nipple  32 . A preferred minimum gap  50  equal to about 0.015 inches greater than the OD of smooth-wall tubular section  26  is preferred. 
   Other alterations and modifications of the invention will likewise become apparent to those of ordinary skill in the art upon reading this specification in view of the accompanying drawings, and it is intended that the scope of the invention disclosed herein be limited only by the broadest interpretation of the appended claims to which the inventors are legally entitled.