Patent Publication Number: US-6216990-B1

Title: Retrofit pan and water heater stand

Description:
This is a continuation-in-part of copending U.S. patent application Ser. No. 08/559,441 filed Nov. 15, 1995 now Pat. No. 5,685,509. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to an appliance pan and stand, and more particularly, to improvements in an appliance pan and stand having a drainage system therein for support of an ignitable appliance, such as a water heater, a central heat and air conditioner or a washer/dryer. 
     An ignitable appliance, such as a water heater, is typically positioned within a limited space of a dwelling and on a floor adjacent the garage or within of a house or basement. Gasoline and other flammable liquids are commonly stored within the garage, and most commonly in cans on the floor. Not infrequently, these flammable liquids are spilled or leaked onto the floor and fumes emanating from these liquids tend to hover and travel low to the floor and travel into the area where the ignitable appliance is disposed. There have been a number of accidents involving an ignitable appliance, such as a water heater, wherein a pilot light of the appliance is an instrument which ignites these fumes resulting in explosion and/or fire. Thus, these ignitable appliances are to be raised above the fumes in a manner to preclude ignition thereof. 
     A drain is normally formed in the floor adjacent the water heater to catch water leakage from the water heater. Since leaks can occur potentially anywhere from the appliance (water heater) the leakage is not necessarily directed toward the drain and can create a mess and defeat the purpose of the drain. 
     There are a variety of different diameter sized appliances, e.g., water heaters, to accommodate a variety of demands. These larger sized appliances are not as common in the market place. In order to accomplish this need and reduce costs of manufacturing, it is desirable to utilize present stands having a base having a predetermined diameter and compliment the top of the stand with a retrofit pan large enough to accommodate the appliance. Further, a need exists to provide a stand with enhanced support of the appliance in extreme conditions, such as an earthquake. 
     Attempts have been made at providing a pan and a stand for a water heater. Such attempts have failed to provide uniformity to the industry safety standards for supporting the ignitable appliance, such as a water heater, under dry or wet conditions. Such attempts also lack height and width adjustability, fail to provide for leakage, or are designed to inhibit maneuverability for assembly and positioning within small work areas. 
     One type of stand described in U.S. Pat. No. 3,519,233 is directed to a water heater stand having four straight legs and a pan with a centrally located drain hole. U.S. Pat. No. 4,267,998 is directed to a wooden stand which requires on-site assembly. Another type of stand disclosed in U.S. Pat. No. 5,199,676 is directed to a sheet-like metal stand which requires assembly at the site. Similarly, this stand lacks drainage directability. Such stands either lack drainage directability, width and height adjustability or is susceptible to weakening from moisture. 
     There exists a need for a relatively inexpensive stand which can elevate the ignitable appliance, such as a water heater, and associated pilot light above the garage floor and/or air region of concern. There is also needed for an appliance stand in order to raise the ignitable appliance, such as a water heater, a desired height while allowing accommodation of the ignitable appliance within the housing environment. Still there is another need to have a stand which is easy to install within a limited work space wherein the ignitable appliance, such as a water heater, is housed and accommodate a variety of sized appliances. There is also a need for a stand to include a pan having a drainage system. Finally, there is a need to provide a safe and stable stand for an ignitable appliance which solves the above needs and brings uniformity to the industry. 
     Accordingly, stand which address and solves some of these problems are described in commonly owned U.S. Pat. No. 5,368,263 and U.S. patent application Ser. No. 08/559,441. The present invention modifies and improves upon the invention described therein. 
     SUMMARY OF THE PRESENT INVENTION 
     It is an object of the present invention to provide a relatively inexpensive retrofit pan and stand which accommodates a variety sizes of ignitable appliances and includes a drainage system and is relatively easy to install. 
     It is an object of the present invention to provide a retrofit pan and appliance stand which is relatively light weight and capable of sustaining relatively heavy ignitable appliance, such as a water heater, for extended periods of time under wet or dry conditions. 
     It is another object of the present invention to provide for a retrofit pan and appliance stand which requires minimal or no assembly. 
     It is still another object of the present invention to provide for a retrofit pan and appliance stand which is relatively safe. 
     It is yet another object of the present invention to provide for a retrofit pan and appliance stand which is easily installed in limited a work area. 
     Accordingly, the invention is directed to a retrofit pan and stand for raising an ignitable appliance, such as a water heater, above a support floor a distance which is above and beyond a region of air lying adjacent the floor which is susceptible to containing flammable fumes emanating from flammable liquids on the floor. The stand includes a base of a predetermined height to raise the ignitable appliance a sufficient distance above the region of air. The base has a support surface for supporting the ignitable appliance and a retention lip member extending from the support surface to retain leakage from the ignitable appliance. Adjacent the retention lip member and the support surface there is at least one preformed threaded aperture formed in a recessed cup surface which provides an opening to which a drain pipe can be threadedly connected thereto. The support surface is preferably arcuately shaped to aid drainage in this regard. In the preferred embodiment, the base is tapered from wide to narrow from the bottom to top of the stand, respectively. 
     The pan has a base with a diameter larger than the retention lip of the stand and having an outer lip member extending from the base and has a support surface interconnecting an inner portion of the lip member. The lip member likewise has at least one preformed threaded aperture formed adjacent at least one of the lip member and support surface of the pan which provides an opening to which a drain pipe can be threadedly connected thereto. The support surface of the pan has at least one support rib which connectedly extends along a bottom surface of the support surface in a manner to provide stability to the support surface of the pan. The rib is configured to seat on the support surface of the stand. More particularly, the rib of the pan support surface shall provide self-orienting aspect with respect to the support surface of the stand in a manner to substantially prevent a degree of freedom of movement therebetween. 
     One embodiment of the an appliance stand for supporting ignitable appliances of various sizes, comprises four generally trapezoidal side panels of a predetermined height and width, each panel having two ends, wherein each end of one of the panels connects to one end of another of the panels such that the side panels interconnect to form a substantially trapezoidal base. The stand has a generally rectangular top support panel having four edges, wherein each edge is connected to an edge of each side panel. The stand has four generally trapezoidal retention lip members of a predetermined height and width connected to an edge of the top support panel and extend substantially along a common plane with the side panel interconnecting thereto, the retention lip members having two ends, wherein each end of one of the retention lip members connects to one end of another of the retention lip members such that the retention lip members interconnect, wherein the top support member and retention lip members form a retainer surface area, at least one threaded aperture surface being formed in a recessed cup surface adjacent one of the retention lips and the support surface to provide an opening adapted to receive a drain pipe thereto. The top support panel is slightly dome shaped to aid drainage. The base is formed with a plurality of ribbed sections to lend strength to the base. In this case, the pan has a rib which extends between the retention lips to maintain the pan in a horizontal fixed position therebetween. 
     Another embodiment of the appliance stand for supporting ignitable appliances of various sizes, comprises a generally frustoconical base member of a predetermined height and width and a generally circular top support member having a peripheral edge, wherein the edge is connected to an edge of the base member. The stand includes a generally frustoconical retention lip member of a predetermined height and diameter connected to an outer surface of the top support member and extends from the peripheral edge of the top support member in a common direction with the base member, wherein the top support member and retention lip member form a water retainer, the threaded aperture surface being formed in a recessed cup surface adjacent the retention lip and the support surface to provide an opening surface adapted to receive a drain pipe thereto. Preferably, the top support member is slightly dome shaped. The base if formed with a plurality of ribbed surfaces to lend strength thereto. Likewise, the pan has a rib which extends between the retention lips to maintain the pan in a fixed position therebetween 
     Other features and advantages of the invention will be apparent to those skilled in the art upon review of the following drawings, detailed description and claims appended hereto. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a stand for use in one embodiment of the present invention supporting an ignitable appliance. 
     FIG. 2 is a perspective view of a stand for use in another embodiment of the present invention. 
     FIG. 3 is a perspective view of a retrofit pan of one embodiment of the present invention for use with the stand in FIG.  1 . 
     FIG. 4 is a perspective view of another embodiment of the retrofit pan for use with the stand in FIG.  2 . 
     FIG. 5 is a bottom view of the retrofit pan of FIG.  3 . 
     FIG. 6 is a bottom view of the retrofit pan of FIG.  4 . 
     FIG. 7 is perspective view showing an oversized ignitable appliance on the retrofit pan of FIG.  4  and of FIG.  2 . 
     FIG. 8 is perspective view showing an oversized ignitable appliance on the retrofit pan of FIG.  3  and stand of FIG.  1 . 
     FIG. 9 is a center cross sectional view of the retrofit pan of FIG.  3  and stand of FIG. 4 in a spaced relation her. 
     FIG. 10 is a cross sectional view of the retrofit pan of FIG.  4  and stand of FIG. 2 taken through line  10 — 10  of FIG.  7 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to the drawings, stands  10 ,  40  and retrofit pans  100 ,  100 ′ support ignitable appliances  12  and  120 , respectively, above a support floor  14 . The ignitable appliance  12  is of a typical size ranging between about 18-20 inches in diameter and ignitable appliance  120  is of a typical size ranging between about 20-24 inches in diameter. The ignitable appliances  12  and  120  are water heaters of differing sizes and each have a generally cylindrical tank housing  16  and  126 , respectively, and optionally a base or support legs  18  and  128 , respectively, which is typically an inch or two inch height. 
     The stand  10  and pan  100 ′ are one complimentary embodiment and stand  40  and pan  100  are another. Each pair will be more fully discussed hereinafter. 
     The stand  10  and retrofit pan  100 ′ are of a width to accommodate and support different sized ignitable appliances  12  and  120  with or without its legs  18  and  128 , respectively. The stand  10  comprises side panels  20 , support surface  22 , retention lip members  24  and a plurality of support ribs  25  and  27  connected to a bottom side of a support surface  22 . The panels  20 , support surface  22 , retention lip members  24  and support ribs  25  and  27  are preferably integrally formed and are made of a plastic material such as polyethylene, cellulosic, polystyrene, acrylic polymers, fluorocarbon resins, nylon, phenolics, polyamides, and silicones, or engineering plastics for sustaining heavy loads, such as polycarbonates, ABS resins, polyvinyl chloride, PPO/styrene and polybutylene terephthalate. Ingredients such as curatives, fillers, reinforcing agents, colorants and fire retardant agents known to the art may be included in the plastic material to achieve a desired set of properties. For example, to provide adequate support for the ignitable appliance, the side panels  20  and support surface  22  thicknesses will vary depending upon the type of plastic materials chosen. Preferably, it will be desirable to form the stand  10  of plastic material which is light weight, fire retardant and capable of sustaining loads in excess of 600 lbs. 
     The retrofit pan  100 ′ includes a base  130 ′ larger diameter than that of the stand  10 , a retention lip  140 ′ extending from the base  130 ′, a support surface  160 ′ connected to the base  130 ′ in a manner to form a retention area between the retention lip  140 ′ and support surface  160 ′. Also, included are a plurality of support ribs  170 ′ and  180 ′ connected to a bottom side of the support surface  160 ′ and are configured to seat on the support surface  22  of the stand  10 . The retrofit pan  140 ′ is likewise made of a material as previously described and is preferably integrally formed. 
     The ribs  170 ′ extend radially inwardly from the base  130 ′ toward a central area  190 ′. The ribs  180 ′ are generally concentrically positioned in spaced relation to one another. Together, the ribs  170 ′ and  180 ′ form a lattice structure highly suitable for supporting the appliance  120 ′. 
     An open surface area  200 ′ seen in FIGS. 5 and 9 is used to receive the retention lip  24  of the stand  10 . In this way, the retrofit pan  100 ′ is locked in place against horizontal freedom of movement. 
     Each of the retention lip members  24  preferably extends from the outer edges  26  of the support surface  22  in a plane common to its respective side panel  20  and in manner such that a tapered structure is formed wide to narrow from bottom to top, respectively. This allows for the stand  10  to be nested one on top of the other in a relatively stable fashion. The height of the retention lip members  24  is to be minimized so that the members  24  do not cause an interference when moving the ignitable appliance  12  for installation and removal thereof. 
     The side panels  20  are also formed with ribbed support surfaces  28  which are substantially equidistantly spaced from one another. The ribbed support surfaces  28  are of a size and configuration to avoid inhibiting the nesting function of the stands  10 . 
     Adjacent the retention lip members  24  and the support surface  22  is formed a preformed threaded aperture  30  in a recessed cup surface  32 . The prethreaded aperture surface  30  is formed such that a drain pipe can be readily attached and enable direction of leakage and connection to a floor drain. Similarly, the retention lip member  140 ′ and support surface  160 ′ have a preformed threaded aperture  142 ′ formed in a recessed cup surface  144 ′. 
     Alternatively, the stand  10  is formed of a plastic material which allows the surfaces  30  and  142  to be self-threading. Additionally, the pipe may be solvent welded about the surface  30  and  142 . In this regard, the recessed cup surfaces  32  and  144  permit adequate access to attach and secure the pipe to the surfaces  30  and  142 . 
     The support surfaces  22  and  160 ′ are slightly arcuate or dome shaped to aid drainage to the recessed cup surfaces  32  and  144 ′, respectively. However, the support surfaces  22  and  160 ′ are of a minimal pitch to allow for quick and stable placement of the ignitable appliance  12  and  120 , respectively, thereon. For example, a pitch of approximately one quarter inch from a center point  34  of the support surface  22  to the point  36  of the support surface  22  adjacent the recessed cup surface  32 . The pitch of the support surface  160 ′ is similarly formed. Finally, a bottom portion of each side panel  20  includes an anchor lip  38  to permit anchoring of the stand  10  to the floor  14 . 
     Referring to FIG. 2, stand  40  is shown. The stand  40  includes a generally frustoconical base panel  42 , support surface  44  having a center point  46 , ribbed support surface  48 , anchor lip  48  and support ribs  55  and  57  which are likewise preferably integrally formed. Also, included is a preformed threaded aperture  52  in a recessed cup surface  54  formed in a like manner to that described above. Similarly, a retention lip  56  extends from an edge  58  away from and along a common frustoconical space as the base panel  42 . 
     The pan  100  is similarly formed to the pan  100 ′ above with the exception of its base  130  and retention lip  140  shape being generally cylindrical and having ribs  170  and  180  configured in accordance with such shape and having an open surface  200  formed therein to receive the retention lip  56  as shown in FIG.  10 . Similarly, the ribs  170  and  180  are configured to seat on support surface  44 . 
     The stands and pans are preferably integrally molded in separate one piece units. Thus, the above described embodiments provide for a pan and stand which can be quickly and readily employed to raise the ignitable appliance to a safe and secure height. The embodiments also provide for an appliance stand which is not susceptible to deteriorating over time and is capable of sustaining ignitable appliances of various sizes in a relatively safe manner. The stand requires little or no assembly and minimal working area in which to install. The symmetrical design aids the ease of installation in that the stand can be set in place with minimal concern as to orientation, and the stand provides means for adapting a drain pipe to a desired side or circumferential location of the stand. Also, the improved design lends well to nesting, has increased strength, and readily permit anchoring to floors. 
     Various other embodiments and variations of the preferred embodiments will be apparent to those skilled in the art and may be made without departing from the spirit and scope of the invention as defined by the following claims.