Abstract:
To address this and/or other needs, the present inventor devised, among other things, a passive moisture detection probe that can be installed and left in place to continuously indicate whether the moisture-content in the wall-cavity of a building is below or above a desirable level. One exemplary moisture detection assembly includes a moisture-absorbent sensor element and an indicator. The sensor element, which can be placed in contact with the inner surface of a home&#39;s exterior sheathing, expands and contracts in response to the moisture content of the sheathing. The indicator, for example a rod, moves in responsive to the expansion and contraction of the sensor element, with its relative position corresponding to the moisture in the exterior sheathing and thus providing an on-going and observable sign of moisture intrusion.

Description:
RELATED APPLICATIONS 
       [0001]    The present application claims priority to U.S. patent application Ser. No. 13/921,203 which was filed on Jun. 18, 2013 and which claims priority to U.S. Provisional Patent Application 61/660,879, which was filed on Jun. 18, 2012. Both applications are incorporated herein by reference in their entirety. 
     
    
     COPYRIGHT NOTICE AND PERMISSION 
       [0002]    A portion of this patent document contains material subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyrights whatsoever. The following notice applies to this document: Copyright © 2012, Alan B. Powell 
       TECHNICAL FIELD 
       [0003]    Various embodiments of the present invention concern moisture detection and indication devices, particularly those suitable for use in buildings. 
       BACKGROUND 
       [0004]    We have a love-hate relationship with water. We love it when it&#39;s where we need it to be, doing what we need it to do. And we hate it when it&#39;s not. The truth of this is readily known around the world by homeowners who have endured the expense, hassle, and sometimes life-threatening consequences of water intrusion into their homes, not only in the highly visible and unescapable form of seasonal flooding, but also in the elusive, often invisible form of moisture intrusion. Which can remain invisible for years until the serious damage of lost structural integrity or mold growth manifest. 
         [0005]    For most stick-frame homes, the type most common in the United States and Canada, moisture intrusions typically occur in theft wail cavities, the six-inch-thick insulation-filled space between a home&#39;s exterior siding and its interior sheetrock. The wood structure and insulation in this wall cavity can act like a large sponge, with outward signs of moisture buildup only becoming visible when the cavity is saturated and the problem is serious. 
         [0006]    Moisture testing of all types of homes, especially stucco homes, is the best way to minimize the risk of water damage and to identify problems before they become serious. Typical testing methods require experts to measure the moisture content in the wall cavities of a home. Generally, this entails drilling holes in the home&#39;s exterior siding or interior sheetrock, inserting highly sensitive electronic moisture meters into its wall cavities. Readings from the moisture meters are then recorded and the holes refilled with caulk or spackle. 
         [0007]    The present inventor has identified at least two problems with this form of testing. The first is that the testing is generally performed only when signs of damage are already being noticed or when a home is on the market, meaning not only that most detected intrusions could have been detected and treated much earlier, but also that homeowners could have saved thousands of dollars in repair expenses. The second problem is that regular testing requires repeated drillings, probings, and refillings. This level of professional effort using expensive measuring instruments puts testing at a price point that many homeowners view as too expensive to perform regularly. 
         [0008]    Accordingly, the present inventor has identified a need for better ways of testing for moisture in buildings. 
       SUMMARY 
       [0009]    To address this and/or other needs, the present inventor devised, among other things, a passive moisture detection probe that can be installed and left in place to continuously indicate whether the moisture-content in the wall-cavity of a building is below or above a desirable level. One exemplary moisture detection assembly includes a moisture-absorbent sensor element and an indicator. The sensor element, which can be placed in contact with the inner surface of a home&#39;s exterior sheathing, expands and contracts in response to the moisture content of the sheathing. The indicator, for example a rod, moves in responsive to the expansion and contraction of the sensor element, with its relative position corresponding to the moisture in the exterior sheathing and thus providing an on-going and observable sign of moisture intrusion. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0010]      FIG. 1  is a center cross-sectional view of an exemplary moisture detection assembly, which corresponds to one or more embodiments of the present invention. 
           [0011]      FIG. 2  is an end view of the assembly in  FIG. 1 , corresponding to one or more embodiments of the present invention. 
           [0012]      FIG. 3  is a top plan view of an exemplary wingnut-style driver tool for use in installing and/or removing the  FIG. 1  assembly, corresponding to one or more embodiments of the present invention. 
           [0013]      FIG. 4  is a profile view of the exemplary wingnut-style driver tool in  FIG. 3 , corresponding to one or more embodiments of the invention. 
           [0014]      FIG. 5  is a profile view of the wingnut-style driver tool in  FIGS. 3 and 5 , corresponding to one or more embodiments of the invention. 
           [0015]      FIG. 6  is a center cross-sectional view of an exemplary drywall bore tool for use in creating the  FIG. 1  assembly, corresponding to one or more embodiments of the invention. 
           [0016]      FIG. 7  is a schematic diagram of an exemplary kit corresponding to one or more embodiments of the present invention. 
           [0017]      FIG. 8  is a center cross-sectional view of another exemplary moisture detection assembly, which corresponds to one or more embodiments of the present invention. 
           [0018]      FIG. 9  is an exploded isometric view of the  FIG. 8  moisture detection assembly and thus corresponds to one or more embodiments of the present invention. 
           [0019]      FIG. 10  is an alternative form of a guide tube portion of the  FIG. 8  moisture detection assembly, which corresponds to one or more embodiments of the present invention. 
           [0020]      FIG. 11  is a front perspective view of an alternative drywall bore tool, which may be used in place of the  FIG. 6  bore tool, and which corresponds to one or more embodiments of the invention. 
       
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       [0021]    This document, which incorporates the drawings and the appended claims, describes one or more specific embodiments of one or more inventions. These embodiments, offered not to limit but only to exemplify and teach the invention, are shown and described in sufficient detail to enable those skilled in the art to implement or practice the invention(s). Thus, where appropriate to avoid obscuring the invention(s), the description may omit certain information known to those of skill in the art. 
         [0022]      FIG. 1  shows cross-sectional view of a passive mechanical moisture detection assembly. The assembly includes an exterior wood sheathing  101  and an interior drywall or sheetrock  102 , with sheathing  101  having an interior sheathing surface  101 A and drywall having a bore hole  102 A. (Although not shown for sake of clarity, the space between the sheathing and drywall is understood to include some form of insulation, such as a fiberglass insulation.) Inserted through bore hole  102 A is an exemplary moisture detection probe assembly  100 . 
         [0023]    Probe assembly  100  includes a probe body  110 , an indicator rod  120 , a spring bias element  130 , a moisture sensor element  140 , and an end cap  150 . 
         [0024]    Probe body  110 , which takes the exemplary form of a right circular cylindrical tube formed of machined, 3-D printed, injection-molded or cast-molded PVC or other durable plastic, includes a sheathing end portion  111 , a drywall end portion  112 , an exterior surface  113 , an interior axial passage or bore  114 . (Drywall and sheathing side modifiers are used as directional cues to facilitate reference to specific portions of other parts and components in this description, without necessarily using reference numbers for those specific portions. For example, indicator rod  120  has a drywall end portion, i.e. end closest to the drywall, and a sheathing end closest to the sheathing.) At the drywall end portion  112 , exterior surface  113  includes integrally formed screw threads  113 A which engage with drywall  102 , specifically the interior surface of bore hole  102 A. Axial bore  114 , which extends the entire length of the probe body from the drywall end portion to the sheathing end portion, includes a first diameter region  114 A and second diameter region  114 C that has a smaller diameter than region  114 A to define an annular ledge or step  114 C. The smaller diameter of region  114 C can be defined as integral dimensional change within bore  114  or by insertion of a separate right cylindrical tube within the probe body. Positioned within axial bore  114  is indicator rod  120 . 
         [0025]    Indicator rod  120 , which is also form of a machined, 3-D printed, or injection-molded or cast-molded PVC or other durable plastic, includes an elongated body portion  121  and a plunger head portion  122 . Elongated body portion  121  and plunger head portion  122  both take the exemplary form of a right circular cylinder, with body portion  121  being substantially longer and having a smaller diameter than plunger head portion  122 . Plunger head portion  122  is larger in diameter than second diameter region  114 C, so that annular ledge  114 C limits axial travel or movement the indicator rod in a direction toward drywall end portion  112 . Plunger head portion  122  has a sheathing side and an opposing drywall side that is integral with the elongated body portion  121  extending through spring bias element  130 . 
         [0026]    Spring bias element  130 , which in the exemplary embodiment takes the form of a helical spring, has respective first and second ends  131  and  132 . First end  131  is seated against annular ledge  114 C, and second end  132  is seated against a drywall side of plunger head portion  122 , thereby biasing the adjacent sensor element  140  into contact with interior sheathing surface  101 A. 
         [0027]    Sensor element  140 , which for example takes the form a right cylindrical plug, includes a water-absorbent (more generally liquid-absorbing) material composition, which not only absorbs water but expands in size at least laterally or axially (along the lengthwise dimension of the indicator rod) during absorption. In the exemplary embodiment, the sensor element consists essentially of Hydrospan  100  material, a commercially available material composition from Industrial Polymers, Inc., 3250 South Sam Houston Parkway East, Houston, Tex. 77047. The Hydrospan  100  material generally expands uniformly in all three of its physical dimensions as it absorbs water, potentially expanding 60% by volume. The Hydrospan  100  material belongs to the Polyurethane chemical family, and has a formula maintained as a trade secret of Industrial Polymers, Inc. However, it is understood to be a reaction product of a Polyether with toluene diisocyanate (TDI).) Other embodiment may use or types of materials that also expand and/or contract, or more generally move, with changing moisture conditions. Some embodiment use composites that include the Hydrospan  100  material in combination with other absorbent or non-absorbent materials to control or restrict its expansion in certain dimensions for example dimensions perpendicular to the axial dimension of the probe body. Other potential materials include urethane resins used in diapers, and polymers used to hold and release water in soils for plant growing. 
         [0028]    As sensor element  140  expands it pushes against plunger head portion  122  of indicator rod  120 , countering the bias of spring bias element  130 . With continued expansion due to persistent presence of moisture in sheathing  101 , the sensor element will expand enough in size along its axial dimension to overcome the spring bias and move the rear portion (drywall end portion) of indicator rod  120  out the rear of the probe body and end cap  150  away from drywall  102 , thereby providing a visual indication that a moisture condition has been detected. 
         [0029]    End cap  150 , in the exemplary embodiment, takes a plastic flange-head form and includes a neck or stem portion  151  bored to engage in an interference fit with the drywall end portion of indicator rod  120  and a flat head portion  152  integrally formed with stem portion  151 . In place of end cap  150 , some embodiments connect the indicator rod to actuate a normally open or normally closed electrical switch. The switch can be electrically coupled in series with an RFID (radio frequency identification) coil to disable or enable an RFID circuit or to circuitry to trigger an audible or visual alarm or to activate a wireless transmitter. In the case of the RFID coil, the switch simply couples or decouples one node or terminal of the coil from the RFID chip. Thus, an attempt to read the RFID tag, for example, will indicate either presence or nonpresence of the tag at the time of the reading. 
         [0030]      FIG. 2  shows an end view of probe body  110 , with endcap  150  removed for clarity. In this view, an opening  116  through which the elongated portion  121  of indicator rod  120  can pass is more clearly visible. Opening  116  include four prongs, of which prong  116 A is representative. The prong opening allows use of a driver tool, such as the exemplary wingnut-style driver tool  200 , shown in  FIGS. 3 ,  4 , and  5 , to install the probe assembly such that its end is generally flush with the interior most surface of drywall  102 . 
         [0031]      FIG. 6 , a center cross-sectional view, shows an exemplary drywall bore tool  600  for use in manually boring holes through drywall or sheetrock, with the holes being suitable for installation of a moisture detection probe, such as probe assembly  100 , as well as for other purposes. Bore tool  600  includes a handle portion  610  and a cutting tube  620 . Handle portion  610  includes a stem portion  611  which is fixedly mounted, for example threadly engaged, adhered, or welded, to cutting tube  620 . Cutting tube  620 , which is made of a durable metal, such as copper, bronze, steel, or aluminum, or a suitable hard and durable polycarbonate or other plastic, includes a sharpened cutting end  621 . The end may be formed to include sawtooth teeth in some embodiments. 
         [0032]    In use, one positions the cutting end of the tube on the location of a desired hole in sheetrock or drywall and uses the handle to push the tool into the drywall, while turning or reciprocating the handle back and forth, in clockwise and counterclockwise directions, until the cutting tube penetrates the drywall. The tool can then be worked with less effort to cut through insulation, thereby forming an effective bore hole or tunnel for installing probe assembly  100 , or other suitable purposes. In the exemplary embodiment, cutting tube  620  forms holes approximately 0.5 or 0.625 inches in diameter to cooperate with a slightly smaller probe body diameter. 
         [0033]      FIG. 7  shows an exemplary moisture detection kit  700 . In the exemplary embodiment, kit  700  includes one or more moisture probe assemblies, such as probe assembly  100  (or  800  in  FIG. 8 ), one or more bore tools, such as bore tool  600  or bore tool ( 1200  in  FIG. 12 ), and one or more installation driver tools, such as wingnut-style driver tool  300 . 
         [0034]      FIG. 8  shows an exemplary moisture probe assembly  800 , which is similar in structure and function to assembly  100  in  FIG. 1 . The main difference between assembly  800  and assembly  100  is the inclusion of a guide tube  810 . 
         [0035]    More specifically, guide tube  810  not only anchors probe body  110 ′ to drywall  102 , but also ensures that it is substantially perpendicularly to the surface of drywall  102  and sheathing  101 , thereby ensuring that the sheathing side of sensor element  140  fully contacts surface  101 A. It is believed that deviation from full endface contact of the sensor element with the monitored surface (surface  101 A) will result in less than optimal performance of the moisture detection probe assembly, since moisture will likely force the sensor element to expand beyond containment of the probe body and thereby reduce transfer of axial expansion force to indicator rod  120 . Guide tube  810  (probe guide tube), shown best in  FIG. 9 , includes a face  811 , and two or more, for example 3 or 4, leaf-spring prongs  812 , and opening  813 . Leaf-spring prongs  812 , are formed as tapered U-channels with the taper increasing with distance away from face plate. Thus, when inserted into a drywall hole and probe body  110 ′ is passed through opening  813 , the probe body spreads the leaf-spring prongs into frictional engagement with the interior surface of the drywall hole, anchoring the guide tube in place. The probe body may then be pushed flush to sheathing surface ends of the 
         [0036]    Other differences between assembly  800  and  100  include an endcap  150 ′ which receives the elongated body portion of indicator rod  120 , internal longitudinal ribs  820  (best seen in  FIG. 9 ) within the axial passage of probe body  110 ′, substitution of flattened exterior threads  113 A′ on probe body  110 . 
         [0037]      FIG. 10  shows an side and perspective views of an alternative guide plate  910  which may be used in place of guide tube  810 . In contrast to guide tube  810  which includes three leaf-spring prongs of substantially equally length, probe guide tube  910  includes two leaf-spring prongs  812  and two opposing thread prongs  814 A and  814 B, which are about half as long as the leaf-spring prongs and which include respective cleats or protusions  815 A and  815 B to better engage with the threads on probe body  110 ′ and thus better ensure the desired perpendicular alignment with the sheathing surface  101 A. 
         [0038]      FIG. 11  shows a profile view of an alternative exemplary drywall bore tool  1100 , which is similar in basic function and structure of drywall bore tool  600  in  FIG. 6 , with the exception of some added features and for ensure higher precision boring and efficiency. Bore tool  1100  includes a handle portion  1110  and a slotted cutting tube  1120 , a bore guide plate  1130 , and a bore guide ring  1140 . Handle portion  1110  includes a stem portion  1111  which is fixedly mounted, for example threadly engaged, adhered, or welded, to slotted cutting tube  1120 . Cutting tube  1120 , which is made of a durable metal, such as copper, bronze, steel, or aluminum, or a suitable hard and durable polycarbonate or other plastic, includes a sharpened cutting end  1121  and includes a longitudinal slot  1123 . The longitudinal slot runs to the top end of the tube to allow full assembly of the tool, though this is not visible in the figure because of handle stem portion  1111 . Bore guide plate  1130  includes a bottom face  1131  with protusions  1132  to engage surface of the drywall being bored and ensure stable position of the tool during boring operations. Plate  1130  also includes a guide stem portion  1133  with an annular guide ridge  1134 . Bore guide ring  1140  includes a slot engagement member  1141  that engages with slot  1123 , enabling the bore guide ring to slide freely along the length of the cutting tube between the cutting end and the handle. Bore guide ring  1140  also includes an annular groove  1142  that slideably engages via snap fit with annular guide ridge  1134 , defining a lateral rotational plane for the guide ring that is substantially parallel to bottom face  1131 . In operation, a user manually places the guide plate over the desired bore location and pushes the cutting tube into the drywall surface (generally substrate surface) using the handle. The handle is then worked back and forth, as with tool  600 , with the guide plate and guide ring maintain perpendicular boring through the drywall and beyond. 
       Conclusion 
       [0039]    The embodiments described above are intended only to illustrate and teach one or more ways of practicing or implementing the present invention, not to restrict its breadth or scope. Nothing presented herein is intended to be construed as critical, required, or essential to the invention as claimed. The actual scope of the invention, which embraces all ways of practicing or implementing the teachings of the invention, is defined only by the following claims including any amendments made during pending of the application and all equivalents of those claims as issued. 
         [0040]    Moreover in this document, relational terms, such as second, top and bottom, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” “has”, “having,” “includes”, “including,” “contains”, “containing” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises, has, includes, contains a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by “comprises a”, “has . . . a”, “includes . . . a”, “contains . . . a” does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises, has, includes, contains the element. The terms “a” and “an” are defined as one or more unless explicitly stated otherwise herein. The terms “substantially”, “essentially”, “approximately”, “about” or any other version thereof, are defined as being close to as understood by one of ordinary skill in the art, and in one non-limiting embodiment the term is defined to be within 10%, in another embodiment within 5%, in another embodiment within 1% and in another embodiment within 0.5%. The term “coupled” as used herein is defined as connected, although not necessarily directly and not necessarily mechanically. A device or structure that is “configured” in a certain way is configured in at least that way, but may also be configured in ways that are not listed. 
         [0041]    The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in various embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter