Abstract:
A wireless air-volume damper control system for regulating air balance in a ducted network, the damper control system having one damper or more damper units installable in the ducted network at locations where air flow in the terminal can be adjusted, the damper units each having a damper blade with a motor to pivot the blade, a power source for powering the motor and pivoting the blade, a receiver and electronic circuitry that operates the motor in response to signals received by the receiver with a portable remote controller having inputs controls and a transmitter that transmits signals to the receiver for operation of the damper unit and a flow volume measuring device for measuring the volume of air flowing in the terminal, the airflow being adjusted by signals from the transmitter of the remote controller in response to measurements from the flow volume measuring device.

Description:
BACKGROUND OF THE INVENTION 
   This invention relates to a wireless air-volume damper control system where it is desired to regulate air volumes in ducted air handling systems by remote adjustments of each volume control damper. 
   The wireless air-volume damper control system is particularly useful in testing, adjusting and balancing of ducted exhaust, heating, ventilating and air conditioning systems. 
   A typical system designed by a professional engineer would contain various components such as fans, coils, filters, inlets, outlets, temperature controls and air volume balancing dampers as design requirements. 
   One requirement, testing and balancing, requires air volume regulation to each inlet and outlet using a balancing damper, and as each change in a discrete damper affects flow in other parts of system, the balancing process is one of multiple adjustments of many volume control dampers. 
   Predicting how an installed ducted system is going to perform is not an exact science and the system must be balanced to achieve a desired flow at each inlet and outlet. Balancing a system requires adjustment of each damper, and as each change in a discrete damper affects flow in other parts of the ducted system, the balancing process is one of tuning, often requiring multiple adjustments of many dampers in a multiple damper system. 
   Adding to the difficulty of balancing flow in a ducted system in a building is the typically concealed location of the dampers within the space above ceiling in each floor of the building. Access is not only difficult, but the process of accessing a damper may result in damage to ceiling tiles or other entry parts provided for adjustment of the dampers. 
   Where flow volumes at building terminals are certified, special equipment is required to quantify air flow making an air balance typically a two man operation, with one man adjusting a damper and another man measuring the volume of air flowing from the affected terminal. These and other difficulties in adjusting existing damper systems make the described wireless air-volume control system advantageous. 
   It is a primary object of this invention to simplify the operation of balancing a ducted network having multiple terminals with multiple dampers by remote adjustment of individual dampers in the ducted system. 
   It is also an object of this invention to provide for remote adjustment by use of a portable wireless controller. 
   It is another object of this invention to freeze a balanced system to prevent unauthorized changes to the system. 
   It is another object of this invention to retain damper settings when power is removed from the system. 
   SUMMARY OF THE INVENTION 
   The wireless air-volume, damper control system of this invention is designed to facilitate the balancing of a ducted network having a plurality of adjustable dampers and terminals. 
   It is to be understood that the invented system is primarily utilized in air conditioning, heating and ventilation systems in buildings, but may be applied to building exhaust systems and other ducted networks where flow control dampers are difficult to access and adjust manually. In the description of this system the term terminal is used both for the intake and discharge vents in the interior or exterior of a structure and includes the protective grille, diffuser or register covering the vent which remain in place during the flow measuring and adjustment process. 
   A ducted network is typically the air duct circuit in a heating and ventilation system, which includes air conditioning or other circulation systems in buildings and structures. The term ducted network also includes formed conduits or conveying tubes designed for specialty applications where a conventional air duct system is not suitable, for example, where the conveyed gas includes corrosive or toxic substances drawn into an exhaust system for atmospheric venting. The term air-volume damper control system is used for the primary conveyance of air, but includes other gases conveyed in a ducted network regulated by flow control dampers. Suitable adjustments in the composition and operation of the controlled damper are contemplated in adapting the wireless air-volume, damper control system of this invention to harsh or extraordinary environments and do not detract from the teachings of the invention disclosure. 
   The wireless air-volume, damper control system of this invention combines a portable handheld remote controller that wirelessly communicates with discrete motor driven dampers to adjust the damper blade and thereby regulate the flow of the controlled gas, usually, air. Preferably, the dampers are wire connected to a reliable and accessible low voltage power source. The damper control system is advantageously designed for a plurality of dispersed dampers in a ducted network typically concealed from sight. 
   Access to individual dampers is therefore frequently difficult and time consuming. Until reliable battery packs are available, hard wiring at the time of installation of the damper system is preferred to eliminate later unscheduled access for battery pack change. A power source remote from the dampers has other advantages in restricting access to the control system. 
   In new buildings where the wireless damper control system of this invention is installed as a part of the scheduled construction, the additional hardware costs for each damper and the greater installation costs for system wiring is more than offset by the savings in facilitated testing and air balance tuning. Elimination of damage to or soiling of newly installed ceiling tiles or access portals adds to the utility of the described system. 
   Following system installation, a number of motor driven dampers or damper units are connected to a selectively activated power source that is conveniently located. In the described embodiment a power connector box with a jack socket is located next to a conventional 120 volt wall outlet for powering a transformer having a cable jack compatible with the jack socket. A convenient, easily interruptable power source is thereby provided for the damper system. 
   The number of dampers on a low voltage circuit are limited and multiple circuits, for example, one or two on each floor, can accommodate the hundreds of dampers that may be required in a modern multi-story building. Each damper in the entire damper system has an individual code key or I.D. to enable the portable controller to discretely access a specific damper and adjust the damper blade to regulate air flow. Electronic measurement of air flow at a particular terminal or vent is conveniently accomplished by a portable flow measuring device having a hood or cowling placeable over the vent. Having a device to remotely adjust a particular damper affecting the air flow at the vent being examined greatly facilitates the initial testing and tuning of the system. The ability of an individual operator to accomplish the task of monitoring air flow while adjusting the damper in real time clearly shortens the time to complete a successful and certifiable air balance. 
   The portable, handheld remote controller provides a wireless manner of communicating with an individual remote damper. In its basic form the remote controller includes a casing with a battery pack, an on-off key with a light indicator, a set of code switches to identify and select a particular damper, and a pair of directional switches, one to open the damper and the other to close the damper. Internally the controller has a transmitter to communicate with the receiver on the identified damper and pass a control signal to operate a drive motor connected to the internal blade of the damper and remotely open or close the damper. 
   For the convenience of the operator testing the flow at a terminal, the flow measuring device includes a handle having a rocker switch for controlling the opening, and closing of the volume control damper being adjusted. A removable cable with end jacks interconnects the flow measuring device and remote controller when this convenient feature is used. In addition, when direct operation of a damper is required, a hand control box with a cable and plug can be directly plugged into a socket on the damper for opening and closing the damper blade using a pair of control switches on the hand control box. 
   Other features include an audible feedback signal provided to indicate the blade is in the fully open or closed position; a worm gear braking drive for the blade provided to hold the blade position when the power is cut to the drive motor on reaching a blade limit position; and, a means of removing the supply of power on completion of a damper balancing session. This last feature prevents unauthorized tampering with one or more dampers for a local climate change that may throw the remaining system out of balance. These and other features of this invention will become apparent on a consideration of the detailed description of the preferred embodiments. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a schematic illustration of the wireless air-volume damper control system with all accessories and a single representative damper unit. 
       FIG. 2  is a schematic illustration of an installed damper control system with multiple damper units 
       FIG. 3  is a side elevational view of the representative damper unit showing the worm gear drive assembly and the connected damper blade. 
       FIG. 4  is a partial cross sectional view of the damper unit of  FIG. 3  with the limit switch mechanism. 
       FIG. 5  is a bottom view of a receiver box in the damper unit with box door opened to show the switch panel. 
       FIG. 6A  is a front view of the wireless remote controller for remotely adjusting a damper unit. 
       FIG. 6B  is side view of the remote controller of  FIG. 6A . 
       FIG. 7  is a perspective view of the alternate hand control box for directly adjusting a damper unit. 
       FIG. 8  is a general schematic diagram of the wireless damper control system. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   The wireless air-volume damper control system is shown in  FIG. 1  as an assemblage of components and is designated generally by the reference numeral  10 . Included in the wireless damper control system  10  is at least one damper unit  12 , a handheld remote controller  14 , a low voltage power supply  16  that connects to the damper unit  12  for powering adjustments to the unit, and an auxiliary hand control box  18  for direct connection and adjustment of the damper unit  12 . In the preferred embodiment a flow measuring device  20  is part of the damper control system, however, other means may be employed for measuring the volume of air flow in an air balancing process, which is the primary use of the described system. 
   In the wireless air-volume damper control system of  FIG. 1 , the motor driven damper unit  12 , shown in greater detail in  FIGS. 2 and 3 , has a duct housing  22  with a flow control mechanism  23  including a pivotally adjustable damper blade  24  having a pivot shaft  26  connected to a drive mechanism  28 . The pivot shaft  26  has an indicator flag  30  that provides an external visual indication of the position of the damper blade  24  within the housing  22 . The drive mechanism  28  is mounted to an interconnecting bracket structure  32  that interconnects the conduit housing  22  with a receiver box  34  which contains the electronics for remote controlling and operating the drive mechanism  28  for adjusting the damper blade  24  in the damper unit  12 . 
   As shown in  FIG. 1 , the low voltage power supply  16  includes a wall transformer  36  which can be plugged into any AC 120 volt outlet for transforming the 120 AC voltage to a 12 volt DC supply in a power cable  38  and jack  40  that plugs into a socket  42  in a power connector box  44 . A low voltage power supply line  46  extends from the conveniently located power connector box  44  to the receiver box  34  of the damper unit. The low voltage wall transformer is sized to accommodate up to 100 damper units that are interconnected in series. An example of a simple low voltage power supply network  48  is shown in  FIG. 2  for a simple conduit network  50  having four damper units. 
   In the damper control system of  FIG. 1 , the handheld remote controller of  14  is shown with a jack cable  52  that inter connects the handheld remote controller of  14  with the flow measuring device  20 . The handheld remote controller, shown in greater detail in  FIG. 6 , has input controls  53  including a rocker switch  54  with an accompanying indicator light  56  for indicating whether the battery powered controller is on or off. In addition, the handheld remote controller  14  includes a series of ten rocker switches  58  for coding in the ID of the damper unit that is remote controlled by the controller. Control buttons  60  and  62  are operated to respectively close and/or open the damper blade  24  of the damper unit  12  remotely. It is understood that the jack cable  52  is only employed for the convenience of the operator and transfers the control button operation from the handheld controller to a rocker switch  64  a support handle of the flow measuring device  20 . 
   Referring to  FIG. 2 , the wireless damper control system  10  is schematically shown installed in a building structure  68 . The simple ducted network  50  includes a supply air duct  70  and a return air duct  72 . It is understood that the supply and return air ducts  70  and  72  are part of a ducted network that connects to a central air system (not shown) that may heat, cool or simply cycle and circulate air throughout the building structure  68 . In the schematic illustration of  FIG. 2 , the supply air duct  70  includes three terminal discharge ducts  74  or terminals  75 , that terminate at ceiling diffuser vents  76 . A balancing damper unit is installed in each terminal  775  to regulate the volume of air flow in the terminal  75 . 
   In the ducted network  50  of  FIG. 2 , the return air duct  72  has an intake duct  74  connected to a damper unit  12  at a ceiling intake vent  78 . Typically, the vents  76  and  78  are similar in appearance and function and are generally defined as part of the terminal  75  or simply, the terminal  75 . Each damper unit  12  is powered by a low voltage power supply  16 , which in the preferred embodiment, comprises the AC/DC wall transformer  36  that is plugged into a conventional wall outlet  80  for supply of low voltage power through the cable  38  that connects to a low voltage power line  46  at a power connector box  44 . In the system of  FIG. 2 , the four damper units  12  connected in series by the low voltage supply circuit  48 . 
   In the schematic illustration of  FIG. 2 , a testing operator is shown holding a flow measuring device  20  against a vent  76  allowing the air flow through the vent to be measured. The operator  82  is wearing the handheld remote controller  14  on a belt  84 . The remote controller  14  is connected by the jack cable  52  to the flow measuring device  20  to allow the operator to adjust the proximate damper unit  12  by the handle controls as previously described. In this manner, a single operator can quickly measure air flow at each of the vents  76  and  78  and simultaneously adjust the associated damper unit  12  to balance the air flow system. As noted, this may require one or more measurements and adjustments at each vent since change in a damper unit setting may affect previously adjusted dampers requiring resetting. Once the damper units  12 , in the terminals  75  of the conduit network  50  are properly adjusted, the wall transformer  36  and jack  40  at the end of cable  38  are removed thereby interrupting the power supply to prevent unauthorized tampering with the balanced air system after adjustment is completed. 
   Referring now to the enlarged view of the damper unit  12  of  FIG. 3 , the drive mechanism  28  is shown to include a gear motor  86  having a drive shaft  88  on which is mounted a worm gear  90 . The worm gear  90  engages a complimentary concentric gear  92  on the pivot shaft  26  of the damper blade  24 . Use of the worm gear  92  provides for self braking and is a preferred means for maintenance of the position of the damper blade  24  when the motor  86  is deactivated by interrupting the power supply  16 . To limit the rotation of the damper blade  24 , a pair of limit switches  94  are mounted to the bracket structure  32  and are selectively activated by a lever  96  projecting from an end fitting  98  on the pivot shaft  26 . 
   The lever  96  as shown in  FIG. 4 , is fan-shaped and can selectively activate a limit switch on the 90 degree travel of the damper blade  24  from a fully closed to a fully opened position. The bracket structure  32  is mounted on the receiver box  34  which includes a door  100  with a hinge  102  and latch  104 . Projecting from the receiver box  34  is an antenna  106  for receiving radio frequency identity code and control signals from the remote controller  14 . As noted, direct control of the motor  86  is provided by use of the hand control box  18 , which is shown in  FIG. 7 . The hand control box  18  includes a cable  108  and jack  110  that plugs directly into the jack socket  112  on the side of the receiver box  34  of  FIG. 3 . 
   Referring now to  FIG. 5 , the receiver box  34  is shown with the door  100  opened to reveal a panel  114  having a set of codes switches  116  that are set to identify this damper unit  12  from others in the damper control system  10 . In addition to the code switches  116 , the receiver box  34  includes a relay  118  and internal circuit connectors  120  for operating the gear motor  86 . An external power connector  122  provides for convenient connection of a compatible connector in the low voltage supply circuit  48 . The integrated electronics of the receiver unit  124  are contained under the panel  114  and are provided as a conventional component by a supplier. Once coded the damper unit  12  will respond only to a signal from a remote controller that is addressed to the matching damper unit. 
   Referring to  FIGS. 6A and 6B , the handheld remote controller  14  is shown with the previously described on/off rocker switch  54  and indicator light  56 , code switches  58  and control buttons  60  and  62 . The control buttons  60  and  62  are marked with a “C” for close and “O” for open, respectively. 
   The remote controller  14  has a jack connector  126  for the jack cable  52  when used in conjunction with the flow measuring device  20  as shown in  FIG. 1 . A panel cover  128  provides for access to a 9 volt battery (not shown) for powering the remote controller  14 . For the convenience of the operator, the remote controller includes a belt clip  130  on the back  132  of the remote controller  14  for convenient attachment of the remote controller to the belt in  84  of an operator  82 , as shown in  FIG. 2 . 
   In  FIG. 7 , the hand control box  18  is shown and includes the cable  108  and jack  110  for connecting the hand control box directly to the damper unit  12  as previously described. The box is shown partially in cross section to reveal the internal 9 volt battery  130  of the type preferred for use in the remote controller  14 . The hand control box  18  includes an on-off switch  132  and controller buttons  134  and  136  for closing and opening the damper blade when the control box  18  is connected to a damper unit  12 . 
   Referring now to  FIG. 8 , the general circuit diagram for the wireless damper system  10  is shown. The wall transformer  36  is plugged into a conventional wall outlet and provides power to the power connector box  44  by cable  38 . The low voltage power line  46  connects the power supply  16  to a damper unit  12 . The damper unit  12  has an internal electronic circuit  136  for operating the damper unit  12  under direction of the receiver unit  124  as controlled by the remote controller  14 . As noted, a portable hand control box  18 , shown in  FIG. 7  may be connected to the damper unit  12  at jack socket  112  for direct control of the damper blade through internal switch circuit  138 . In the diagrammatic illustration shown in  FIG. 8 , the handheld remote controller  14  is illustrated transmitting a signal from the internal transmitter unit  134  to the receiver unit  124  of the damper unit  12  identified by the settings of the manual rocker switches  58  of the input controls  53 . The damper blade  24  of the selected damper unit is opened or closed as desired by the operator  82 . When the damper blade  24  reaches the fully open or fully closed position, the lever  96  contacts a switch  94 , cuts power to the gear motor  86  and creates an audible signal at sound generator  140 . 
   In an air balancing operation using the preferred air flow measuring device  20 , the jack cable  52  is connected to the handheld remote controller  14  and to the flow measuring device  20  as shown in  FIG. 1 . A short jack cable  142  connects the extended handle  66  to an internal circuit (not shown) in the base portion  144  of the flow measuring device  20  allowing the rocker switch  64  at the end of the handle  66  to control the balancing damper for the inlet or outlet being tested. During the test, the hood portion  146  of the flow measuring device  20  is held up against a terminal  75 , such as the supply vent  76  as schematically illustrated in  FIG. 2 . 
   The flow measuring device  20  has a step switch  148  and meter  150  to provide the operator with a real-time measure of the volume of air flow. While viewing the meter  150  the operator adjusts the target damper unit  12  until the desired flow volume is achieved. The operator continues to test the terminals  75  and adjust the associated air balance damper unit  12  until the system is performing as desired. As noted, this process may require testing and adjusting the same terminal and damper unit more than a single time to assure compliance with a desired result. 
   While, in the foregoing, embodiments of the present invention have been set forth in considerable detail for the purposes of making a complete disclosure of the invention, it may be apparent to those of skill in the art that numerous changes may be made in such detail without departing from the spirit and principles of the invention.