Abstract:
Apparatus for and a process of making and stocking humidifiers for hot air heating systems resides in providing a selected number of humidifier modules of the bypass type, providing a lesser number of power modules each having a motor driven fan, employing the humidifier modules alone in heating systems calling for a bypass humidifier, and optionally combining a power module with a humidifier module for converting the humidifier to a powered humidifier for heating systems calling for a powered humidifier. Optional control modules may also be provided and employed as needed. The modules are assembled side by side. The process and apparatus eliminate the need for manufacture, stocking and supply of two different styles of hot air furnace humidifiers, i.e., bypass humidifiers and powered humidifiers, inasmuch as a single humidifier module now suffices. Substantial convenience, economy and cost savings are thereby realized.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to humidifiers, particularly humidifiers for hot air furnaces and heating systems. 
       BACKGROUND 
       [0002]    Humidifiers for hot air furnaces and space heating systems are typically comprised of a housing having an air inlet and an air outlet for passing space heating air from the furnace through the housing and over and/or through a water fed evaporator in the housing for moistening the heating air passing through the housing and to the space heating system. The structure, mode of operation and beneficial effects of hot air furnace humidifiers are well known. 
         [0003]    The humidifiers are comprised basically of two types, namely, the bypass humidifier and the powered humidifier, i.e., a humidifier that includes a motor operated fan for inducing airflow through the humidifier housing and the evaporator. 
         [0004]    A typical bypass humidifier installation is illustrated schematically in accompanying  FIGS. 1  in association with a hot air furnace  1  having warm or hot air supply ducting  2 , cool or cold air return ducting  3  and an internal blower (not shown) for forcing heated air from the furnace  1  through the ducting  2 , to a space to be heated and for pulling or drawing cool air from said space through the ducting  3  back to the furnace to be reheated and re-circulated through the space. A bypass humidifier  4  has an inlet  5  in its back wall connected in fluid (gaseous) communication with one or the other of the ducts  2  and  3 , usually the hot air supply ducting  2 , and an outlet  6  connected in fluid (gaseous) communication with the other of the ducts, usually the cool air return ducting  3 . Due to the differential between the relatively higher pressure airflow in the supply ducting  2  and the relatively lower pressure airflow in the ducting  3 , air is induced to flow from the supply ducting  2  through the humidifier  4  to the return ducting  3 , thereby causing air to flow over and/or through an evaporator unit  7  in the housing  4  to moisturize, i.e., humidify, the air flowing through the space heating system. A damper  8  installed at the outlet  6  of the humidifier controls the amount of air passing through the humidifier  4  and thus the amount of moisturized air delivered to the space to be heated. 
         [0005]    A typical powered humidifier installation is illustrated schematically in accompanying  FIGS. 2  in association with a hot air furnace la having hot air supply ducting  2   a , cold air return ducting  3   a  and a self contained blower (not shown) for forcing heated air through the ducting  2   a  to a space to be heated and for pulling or drawing cool air from such space through the return ducting  3   a  back to the furnace to be reheated and re-circulated through said space. A powered humidifier  4   a , including a motor driven fan  9  is mounted on and connected with one of the ducts  2   a  and  3   a , usually the hot air supply ducting  2   a . The humidifier has internal partitions and one or more openings in its rear wall defining one or more inlets  5   a  to and one or more outlets  6   a  from the fan  9 . Typically, the humidifier  4   a  includes a moveable or removable cover or front wall  9   a  for accommodating access to and replacement of the water bearing media or filter pad employed in evaporative unit  7   a . The motor driven fan  9  is customarily mounted on and movable with the cover  9   a . Motor driven fan  9  is required for the powered humidifier  4   a  in order to draw some of the heated air from the duct  2   a  through the inlets  5   a , to force that air over and through evaporator unit  7   a  to moisturize the air, and to force the moisturized air through the fan outlet  6   a  back into the supply duct  2   a.    
         [0006]    Due to the wide variety of hot air heating systems available, both for home and commercial heating installations, the bypass humidifier is suitable for some systems and/or installations, but not for others. Similarly, the powered humidifier is suitable for some systems and/or installations, but not for others. The current state of the art requires the existence of two types of hot air furnace humidifiers, the bypass humidifier and the powered humidifier. 
         [0007]    Manufacturers are thus required to make two different types of humidifiers; distributors, supply houses and stores are required to stock two different types of humidifiers; and installers and repair personnel are required to stock and carry on their customer service vehicles or trucks the two types of humidifiers. 
       SUMMARY 
       [0008]    One object of the present invention is to eliminate the need for two different types of humidifiers for hot air furnaces. 
         [0009]    Further, it is an object of the invention to provide a hot air furnace humidifier comprised of a bypass humidifier and a method and a kit for converting the bypass humidifier to a powered humidifier. 
         [0010]    It is more particularly an object of the invention to provide a hot air humidifier consisting essentially of a single humidifier module usable per se as a bypass humidifier and a selectively usable conversion module, namely a power module, optionally connectable to the humidifier module, for converting the humidifier module from a bypass humidifier to a powered humidifier. 
         [0011]    Yet another object of the invention is to provide a powered humidifier wherein the motor driven fan is mounted on the humidifier housing or base along side the evaporative unit, rather than on the humidifier cover, thereby to eliminate the inconvenience, bulk and awkwardness of current cover mounted fan designs. 
         [0012]    In accordance with the invention, two compatible modular units are provided. The first unit or module, herein called the humidifier module, is essentially a bypass humidifier comprised of a housing having an air inlet and an air outlet and a water fed evaporator mounted in the housing in such manner that airflow from the inlet to the outlet is compelled to pass over and/or through the evaporator unit as required by the evaporator design. The second unit or module, herein called the power module, comprises a housing having an air inlet, an air outlet and a motor driven fan in the housing for inducing air to flow from the air inlet to the air outlet. 
         [0013]    The inlet of the power module is adapted for connection in fluid (gaseous) communication with the outlet of the humidifier module for pulling or drawing air from a furnace air duct through the humidifier and forcing moisturized (humidified) air back into the furnace air duct, preferably the same duct. Alternatively, the power module outlet maybe connected to the humidifier module inlet for forcing air through the humidifier module. In either case, only one style or type of humidifier module is required. 
         [0014]    In accordance with the method of the invention, the humidifier module will be provided, i.e., made and/or stocked, in a number needed to meet the total market demand for humidifiers, i.e., the demand for both bypass humidifiers and powered humidifiers; and the power unit or module will be provided, i.e., made and/or stocked, in a smaller number, i.e., only the number needed to meet market demand for powered humidifiers. 
         [0015]    The housings of the two modules are of compatible and mating design and the power module is optionally mountable on or connectable with the humidifier module to impart the appearance of a unitary product. The humidifier module is thus directly usable by itself as a bypass humidifier, and is quickly, easily and economically converted from operation as a bypass humidifier to operation as a powered humidifier. 
         [0016]    Manufacturers, suppliers, stores, installers and repair personnel thus need, make and/or stock only one type of hot air furnace humidifier and, in a much smaller number, power module kits for converting bypass humidifier modules to powered humidifiers. This results in substantial costs savings and other economies at all levels in the channels of trade from manufacture to the ultimate consumer. 
         [0017]    In a further embodiment of the invention, an optional control module is provided, particularly for use with the humidifier in its powered mode of operation. The control module appropriately houses temperature and humidity responsive devices for controlling the supply of water to the evaporator unit and for controlling operation of the motor driven fan, i.e., for turning the fan on and off and/or controlling the speed of the fan. The control module is optional, for use when relatively precise humidity control is desired, thus further contributing to the cost savings and market efficiencies provided by the invention. 
         [0018]    Additionally, the power module, and the control module if used, are attached respectively to the side walls or base of the humidifier housing along side the evaporative unit, thereby enabling an unobstructed (i.e., motorless) independently moveable or removable front wall or cover for the humidifier, thereby facilitating ease of access to and replacement of the evaporative medium or filter pad. 
         [0019]    These and other objects and advantages of the invention will become apparent to those of reasonable skill in the art from the following detailed description as considered in conjunction with the accompanying drawings. 
     
     
       IN THE DRAWINGS 
         [0020]      FIG. 1A  is a fragmentary and schematic illustration in plan view of a hot air heating system utilizing a bypass humidifier; 
           [0021]      FIG. 1B  is a fragmentary and schematic illustration in elevation of the heating system of  FIG. 1A ; 
           [0022]      FIG. 2A  is a fragmentary and schematic illustration in plan view of a hot air heating system utilizing a powered humidifier; 
           [0023]      FIG. 2B  is a fragmentary and schematic illustration in elevation of the heating system of  FIG. 2A ; 
           [0024]      FIG. 3  is a perspective view of a hot air furnace bypass humidifier provided as a humidifier module in accordance with the invention; 
           [0025]      FIG. 4  is a perspective view of a motor driven fan assembly provided as a power module in accordance with the invention; 
           [0026]      FIG. 5  is a perspective view of a humidifier control module provided in accordance with the invention; 
           [0027]      FIG. 6  is a perspective view from the top right showing the power module of  FIG. 4  assembled with the humidifier module of  FIG. 3  to comprise a powered hot air furnace humidifier in accordance with the invention; 
           [0028]      FIG. 7  is a perspective view from the left showing the power module of  FIG. 4  and the control module of  FIG. 5  assembled with the humidifier module of  FIG. 3  to comprise a second embodiment of a powered humidifier provided in accordance with the invention; 
           [0029]      FIG. 8  is a front elevation of the powered humidifier of  FIG. 7  showing the same with the front walls or covers of the humidifier and power modules removed; 
           [0030]      FIG. 9  is a perspective view from the left of the powered humidifier as illustrated in  FIG. 8 ; and 
           [0031]      FIG. 10  is a perspective view from the top right of the powered humidifier as illustrated in  FIG. 8 . 
       
    
    
     DETAILED DESCRIPTION 
       [0032]    The following is a detailed description of certain embodiments of the invention presently deemed by the inventor to be the best mode of carrying out his invention. 
         [0033]    Referring to the drawings;  FIGS. 3 ,  8 ,  9  and  10  illustrate a humidifier module  10  comprised of a housing  12  containing therein an evaporator unit or assembly  14 . 
         [0034]    An exemplary evaporator  14  is comprised of a solenoid operated water valve  16  at the top of the housing  12 , a header tray or distributor  18  for receiving water from the valve  16  and distributing it uniformly onto the upper marginal portions of an evaporative element  20 , a collector tray  22  for collecting excess water from the filter element  20 , and a drain  24  leading from the tray  22  to a suitable location for disposal of excess water. The evaporative elements are well known in the art, for example slit and expanded metal pads that provides an evaporative surface for air flowing through the element. Alternative evaporators may be used, including wicking types, For the purposes of this application, the term “evaporator” includes all devices for evaporating water to provide humidification. 
         [0035]    An inlet port, hole or aperture (not shown) is formed in the back wall of the housing  12  to accommodate the flow of air from the hot air duct or plenum into the housing and through the moistened filter element  20  to add moisture to and increase the humidity of the air passing through the filter. 
         [0036]    To accommodate egress of moisturized air from the housing  12  in the direction best suited for a particular heating system, thereby to meet the requirements of the variety of heating systems encountered in the trade, the housing  12  has a first air port  26  in one side wall and a second air port  28  in its other side wall. Depending on the requisite direction of egress of moisturized air, one of the ports  26  and  28  comprises an air outlet from the housing  12  and the other of the ports  26  and  28  is capped or blocked off to preserve the integrity of the path of air flow through the humidifier module. For example, in a bypass humidifier installation, the right hand port  28  in the housing  12  would comprise the humidifier air outlet and the left hand port  26  would be capped by a suitable closure plate or the like (not shown). In a powered humidifier installation, the power module could be coupled to either the left hand port  26  or the right hand port  28  in housing  12  and that other port  28  or  26  would be blocked by a closure plate or a control module to be described below. 
         [0037]    The evaporator unit or assembly  14  may be of any design conventional in the art. Essentially, an evaporator unit or assembly comprises means (valve  16 ) for supplying water to the housing  12  and one or more water evaporative elements  20  so designed and so mounted and disposed within and relative to the housing  12  that air entering through the inlet port and exiting through the outlet port is compelled to flow over and/or through the element  20 . The element  20  is typically saturated with water so that the air passing over and/or through the element  20  will be moisturized and the air exiting the housing  12  will be at a higher humidity then the air entering the housing. 
         [0038]    To the extent thus far described, the humidifier module  10  comprises a bypass humidifier adapted to be installed in a hot air heating system. The inlet port in the back wall of the housing  12  is connected in gaseous communication with one of the hot air supply or cold air return ducts and the selected outlet port  26  or  28  is connected in gaseous communication with the other of the hot air supply or cold air return ducts of the furnace. Due to the pressure differential between the furnace air in the supply ducts and the furnace air in the return ducts some of the total heating system airflow will be diverted, i.e., will bypass, from the supply duct to the return duct through the humidifier  10  for adding moisture to the warm or heated air from the furnace. Depending on the specific design of the air moistening element or elements  20 , optimum results will usually and preferably be obtained by connecting the air inlet port in gaseous communication with the furnace air supply duct and by connecting the air outlet port in gaseous communication with the furnace return air duct. To control the amount or degree of air flow through the humidifier, a damper of conventional design is preferably mounted adjacent the air outlet port  26  or  28 . 
         [0039]    The module  10  is thus usable per se, i.e., by itself, as a bypass humidifier. 
         [0040]    Where a particular hot air heating system or furnace is not designed for or is not optimally suited for the use of a bypass humidifier, the present invention provides an optional attachment for converting the module  10  from operation as a bypass humidifier to operation as a powered humidifier. 
         [0041]    Referring to FIGS.  4  and  6 - 10 , a power module  30  for optional attachment to the module  10  is comprised of a housing  32 , an electric motor  33  mounted within the housing and a fan  34 , suitably a centrifugal fan mounted concentrically about the motor  33 . The fan is operatively associated with the motor and so mounted and disposed within and relative to the housing  32  as to induce and compel air to flow from an air inlet  36  in one side wall of the housing, into and through the housing and to exit through an air outlet (not shown) in the rear or back wall of the housing. 
         [0042]    The power module  30  is invertible, that is, it may be inverted from a first position wherein the air inlet  36  is located at the right side of the housing  32  to a second position wherein the air inlet  36  is located at the left side of the housing  32 . Consequently, the module  30  can be assembled either to the left side of the module  10 , with the air inlet  36  of the module  30  in alignment and gaseous communication with the port  26  on the left hand side of the module  10 ; or the module  30  can be inverted and mounted on the right side of the module  10  with the air inlet  36  in alignment and fluid communication with the port  28  on the right hand side of the module  10 . The modules  10  and  30  thus accommodate ambidextrous assembly of the modules, with the powered module on either the right side of the humidifier module or on the left side of the humidifier module, as may be needed for particular installations. 
         [0043]    In both of its alternative locations, the motor driven fan is mounted at the side of the humidifier, thus leaving the front wall or cover unobstructed and uncluttered, so that the wall or cover may easily, independently and conveniently be moved or removed for ease of access to and replacement of the pad or medium  20 . 
         [0044]    The housing  12  of the module  10  is of a particular size, configuration and design to accommodate the contained evaporator  14  and to impart a pleasing and desirable appearance to the exterior of the module  10 . The housing  32  of the module  30  is preferably of a size, configuration and design compatible with and complementary to that of the housing  12  so that when the two modules are assembled with one another as illustrated in  FIG. 6 , they will convey the appearance of a unitary product of esthically pleasing design. 
         [0045]    As illustrated in  FIG. 8 , the housing  32  of the module  30  is adapted to be attached and secured to the housing  12  of the module  10  in any conventional manner, e.g., by a series of bolts or similar fasteners (not shown). The housing of each module preferably comprises a base adapted for attachment to a furnace and/or another module and a cover. The cover is at least partially removable from the base to provide access to the module for service, such as replacing the evaporative element in humidifier module  10 . As shown in  FIGS. 8-10 , the base of module  30  is secured to the base of module  10  without obstructing the covers of either module. Because the power module is not attached to the humidifier module cover, the cover may easily be lifted or removed from it s base. 
         [0046]    The housing  32  is assembled with the housing  12  so that the air inlet  36  of housing  32  is in fluid communication with one or the other of the air outlet ports  26  and  28  in the housing  10 . The assembled modules  10  and  30  thus comprise a powered humidifier wherein air is compelled by the fan  34  to flow through the inlet port in the back wall of the housing  12 , into the housing, over and/or through the evaporative element  20 , into the housing  32  and out through the exit port in the back wall of the housing  32 . 
         [0047]    Where conditions so indicate, the powered humidifier of  FIGS. 5 and 6  can be used in lieu of a bypass humidifier. A powered humidifier comprised of modules  10  and  30  will customarily be connected in communication with either the hot air supply duct or the cold air return duct, usually the hot air supply duct. The inlet port in the back wall of the module  10  will be connected to the duct at a first location and the outlet in the back wall of the module  30  will be connected to the duct at a second location. The two locations can be side by side and together comprise one opening in the duct. When operational, furnace air will be compelled by the fan in the power module to flow through the humidifier module  10  and evaporative element  20  to add moisture to the air that is conducted to the space to be heated, thereby increasing the humidity of the air within such space. 
         [0048]    The invention thus provides a universal humidifier for use with all hot air heating systems, whether a given system calls for a bypass humidifier or a powered humidifier. In both cases, air flow is accommodated either from left to right or from right to left. 
         [0049]    Manufacturers, suppliers, stores, installers and repair personnel thus need make, stock and carry only a single humidifier. The singular humidifier module  10  is made and stocked in a number adequate to meet total humidifier demand and the power module  30  need be made and stocked only in a number (a significantly lesser number) adequate to meet the demand for powered humidifiers. Substantial advantages, economies and costs savings are consequently realized in all stages of the channels of trade, from manufacturer to consumer. 
         [0050]    For some hot air furnace humidifier systems and/or installations it may prove desirable to provide means for controlling the delivery of water to the evaporator unit or assembly  14  and/or for controlling the times and duration of operation and/or the speed of operation of the motor driven fan  34 . To satisfy this demand the present invention provides another modular unit, namely, a control module  40  as depicted in  FIGS. 5 ,  7  and  8 - 10 . 
         [0051]    The module  40  is comprised of a housing  42  of a size, shape, configuration and design compatible with and complementary to that of the modules  10  and  30  so that when the same are assembled together, as illustrated in  FIGS. 7-10 , they will convey the appearance of a unitary product of pleasing design. The control module  40 , like the power module  30 , is invertible so that it may be assembled onto either the left hand side or the right hand side of the humidifier module housing  12 , as may be required. In powered humidifier installations, the power module  30  will be mounted on the side of the humidifier module  10  dictated by the requisite direction of air flow, and the control module  40  will be mounted on the other side of the module  10  where it serves, among other functions, to close or block off the unused one of the ports  26  and  28 . 
         [0052]    Contained within the control module housing  42  are physical, electrical and/or electronic components responsive to the temperature and humidity of the furnace and/or room air to ( 1 ) turn the fan motor of the power module on or off and/or to control the speed of the motor and ( 2 ) to control the delivery of water to the evaporative element  20 , for example, via a solenoid operated water valve  16 , thereby to attain and maintain a predetermined degree of relative humidity in the air being conducted by the furnace blower through the space to be heated. The control circuitry for the humidifier preferably comprises a temperature sensor/transmitter unit (thermostat) and a humidity sensor/transmitter unit (humidistat) installed at an appropriate location or locations in the room or space heating and furnace system and, contained within the housing  42 , a wireless temperature receiving unit, a wireless humidity receiving unit, a transformer  44 , a thermister  46  and suitable switches and electrical/electronic components for operating the solenoid valve  16  and the motor  33  of the fan  34 . No hard wiring to the furnace circuits is required. As used herein the term “means for controlling humidity output” means any mechanical, electrical and/or electromechanical device or assembly for controlling humidity output of the humidifier, including but not limited to the aforesaid solenoid operated water valve to selectively provide water to the evaporative element, a blower controller for energizing and/or controlling the speed of the fan motor, and a solenoid operated damper for controlling air flow through the humidifier module. 
         [0053]    The control module  40  also preferably includes circuitry and indicators, such as differently colored lights  48 , for indicating, for example, that the humidifier is on, i.e., that power is being supplied to the humidifier (green light), that the evaporator  20  needs to be inspected, usually a function of “on” time (red light) and that the timing circuit needs to be reset (blue light), together with a reset button  50  for resetting the timing or count down circuit 
         [0054]    The invention thus provides a modular assembly comprised of one, two or three modules to meet all industry, commercial and residential requirements for hot air furnace humidifier applications. Each module need be made and stocked only in a respective number anticipated to be necessary to meet the demand for respective humidifier types or styles. 
         [0055]    The objects and advantages of the invention have thus been shown to be attained in a convenient, economical, practical and facile manner. 
         [0056]    While preferred embodiments of the invention have been herein illustrated and described, it is to be appreciated that various changes, rearrangements and modifications may be made therein without departing from the scope of the invention as defined by the appended claims.