Abstract:
A remote controlled air vent is provided comprising at least one closure member, and a vent control unit. The at least one closure member (e.g., a plurality of louvers) may be configured to control the egress of the air from the air vent and the vent control unit may control displacement of the at least one closure member in response to a wireless control signal. In one exemplary embodiment, the vent control unit may comprise a mechanical component to control displacement of the at least one closure member, and an electrical component including a wireless receiver to receive the wireless control signal. The invention extends to a method and system to control the egress of air from an air duct,

Description:
[0001]    The present patent application is a continuation of prior application Ser. No. 10/166,969 filed Jun. 10, 2002, entitled Computer Controlled Air Vent which claims the benefit of U.S. Provisional Application No. 60/296,743, filed Jun. 11, 2001. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    This invention relates generally to heating, ventilation, and air conditioning (HVAC) systems and more particularly to computer-controlled air vents.  
         DISCUSSION OF PRIOR ART  
         [0003]    In residential HVAC systems it is not customary to install a HVAC control thermostat in each individual room of a house, and therefore it is difficult to maintain a uniform temperature environment in all rooms. Typically, the only room having a controlled temperature environment is the room in which the control thermostat is located. Frequently, a system using a single control thermostat results in “cold” rooms or “hot” rooms in other parts of the building, due to exposure, location, heating duct configuration, and other causes. In order to heat a “cold” room, the single control thermostat is typically set at a higher level, but this increases the temperature in the other rooms that are normally at a higher level. In order to cool a “hot” room, the single control thermostat is typically set a lower level, but this decreases the temperature in the other rooms that are normally at a lower level. As a means of compensating for these temperature differentials, the standard air vents in each room are equipped with manual mechanical louver arrangements which will control the flow of air from 0% to 100%. However, any manual adjustments made to the air vents are static once made. Thus, although a register in a “hot” room could be manually adjusted to restrict the flow of air passing through it, this adjustment could result in the same room becoming a “cold” space unless the vent is later manually adjusted to the open position.  
           [0004]    A particular problem faced by conventional HVAC systems is that the individual rooms of a building have different volumes, and thus are heated or cooled at different rates. For example, in a system having a small room and a large room, the small room will heat and cool more quickly than the large room. When the central thermostat is adjusted to a target temperature, the smaller room typically achieves the target temperature before the larger room, but because the manual air vents remain open, warm or cool air that could be used to heat or cool the larger room continues to pour into the small room, thereby wasting energy and causing overheating or overcooling. Consequently, the smaller room feels stifling or frigid.  
           [0005]    An inherent problem with conventional HVAC systems is that they do not provide the proper amount of heating and cooling to all rooms proportionately. Additionally, such systems do not account for the changing variables that affect the thermal management needs of each room. These variables include people and equipment changes, external sun or snow loading, rain, daytime vs. nighttime needs, weekend vs. weekday needs, etc. It is possible to accommodate these changes manually by repeatedly opening and closing the air vents throughout the day, but such procedures are too time-consuming and labor-intensive to be practical or cost-effective. Consequently, uneven heating and cooling of the facility results, with smaller rooms heating or cooling faster (and to a greater degree) than larger rooms. As a result, more energy is consumed than is needed to maintain a comfortable environment.  
           [0006]    The shortcomings of residential HVAC systems are more acute in commercial settings, where the cost of heating or cooling small to large buildings significantly impacts the profit margins of the business enterprises that occupy these buildings. The problem is somewhat alleviated in large commercial buildings, which are built to include elaborate cost-saving lighting, heating and cooling control systems that offer significant energy savings. Such systems typically include multiple HVAC zones, with each zone covering one or more workspaces within the building. In smaller business settings most heating and ventilation systems employ a single zone HVAC unit to supply conditioned, heated or cooled air to more than one distinct zone or room. However, in both large and small buildings, each room or zone may have different comfort requirements due to occupancy differences, individual preferences, and exterior heat and cooling load differences. The smaller business types of systems are referred to as single zone HVAC units because they are controlled from one centrally located OFF/ON thermostat controller. In a building having multiple zones that have different heating and cooling requirements, there is often no one, good representative location for the installation of a thermostat controller.  
           [0007]    As in residential houses, smaller workspaces in commercial buildings tend to heat and cool faster than larger workspaces. This problem is exacerbated because commercial air vents typically do not include manual adjustment means. Additionally, the air vents found in commercial buildings are often located in the ceilings, which, unlike the ceilings in residential houses, may be approximately  8  feet or more above the floor. Consequently, individuals are often not able to adjust the airflow within their personal workspaces. In cases where manual adjustment means are provided, adjusting the air vents typically necessitates standing on a chair, desk, or ladder, which is inefficient and potentially hazardous.  
           [0008]    The prior art provides a number of noteworthy attempts to create systems which address the problems of controlling the diverse needs of single and multi-zoned HVAC systems. Some of these systems describe remote controllers for starting and stopping an HVAC apparatus. Other systems describe wax motors and bimetallic elements that close louvers disposed within an air register as the temperature of a room increases, and that open the louvers as the temperature of the room decreases. Further systems describe motors connected to louvers for opening and closing the louvers in response to control signals received from a centrally mounted controller. Still other systems describe variable air valve (VAV) units installed within the ducts of a HVAC system and hard-wired to a central remote controller. Yet other systems describe wireless remote thermostats that take over the temperature sensing and control functions of a central thermostat. However, the above systems are disadvantageous on a number of levels.  
           [0009]    Firstly, the motorized air registers tend to be mechanically complex and difficult to install. Additionally, the air registers tend not to be computer-controlled. Furthermore, the motors are typically hard wired to a power source. Secondly, the remote control units tend to control the HVAC unit itself and not the individual air registers. Thirdly, the bimetallic elements tend to open the air louvers as a room cools, thereby resulting in overcooling. Fourthly, where remote controllers are used to start and stop an HVAC unit, uneven cooling results throughout each HVAC zone because the registers within each zone are often manually controlled.  
         SUMMARY OF THE INVENTION  
         [0010]    A remote controlled air vent is provided comprising:  
           [0011]    at least one closure member configured to control the egress of air from the air vent; and  
           [0012]    a vent control unit to control displacement of the at least one closure member in response to a wireless control signal.  
           [0013]    The vent control unit may comprise a mechanical component to control displacement of the at least one closure member; and an electrical component including a wireless receiver to receive the wireless control signal.  
           [0014]    The invention extends to a method and system to regulate the egress of air from an air vent and air duct. 
       
    
    
       [0015]    Other features of the present invention will be apparent from the accompanying drawings and from the detailed description that follows.  
       BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    The present invention is illustrated by way of example, and not limitation, in the figures of the accompanying drawings, in which:  
         [0017]    [0017]FIG. 1A is a diagram illustrating the use of a computer-controlled air vent, according to one embodiment of the invention;  
         [0018]    [0018]FIG. 2 is a diagram illustrating installation of a computer-controlled air vent into an air duct outlet of a conventional HVAC system, according to one embodiment of the invention;  
         [0019]    [0019]FIG. 3 is an exterior front perspective view of a computer-controlled air vent, according to one embodiment of the invention;  
         [0020]    [0020]FIG. 4 is a bottom perspective view of the computer-controlled air vent of FIG. 3, according to one embodiment of the invention;,  
         [0021]    [0021]FIG. 5 is another bottom perspective view of the computer-controlled air vent of FIG. 3, according to one embodiment of the invention;  
         [0022]    [0022]FIG. 6 is a cut-away side view of the computer-controlled air vent of FIG. 3, according to one embodiment of the invention;  
         [0023]    [0023]FIG. 7 is another bottom perspective view of the computer-controlled air vent of FIG. 3, according to one embodiment of the invention;  
         [0024]    [0024]FIG. 8 is a perspective end view of the computer-controlled air vent of FIG. 3, according to one embodiment of the invention;  
         [0025]    [0025]FIG. 9 is a perspective view of one embodiment of a component housing usable with the computer-controlled air vent of FIG. 3, according to one embodiment of the invention;  
         [0026]    [0026]FIG. 10 is an end perspective view of a mechanical linkage assembly used to rotate airflow louvers housed within the computer-controlled air vent of FIG. 3, according to one embodiment of the invention;  
         [0027]    [0027]FIG. 11 is a perspective view of a louver assembly in an open position, according to one embodiment of the invention;  
         [0028]    [0028]FIG. 12A is a side view of a cam used to rotate the louver assembly of FIG. 11, according to one embodiment of the invention;  
         [0029]    [0029]FIG. 12B is a cross-sectional side view of the cam used to rotate the louver assembly of FIGS. 10 and 11, taken along the line A-A of FIG. 12A, according to one embodiment of the invention;  
         [0030]    [0030]FIG. 12C is an end view of the cam of FIG. 11, according to one embodiment of the invention; t  
         [0031]    [0031]FIG. 12D is a plan view of the cam of FIG. 11, according to one embodiment of the invention;  
         [0032]    [0032]FIG. 13 is a perspective view of a temperature adjustment system that includes a plurality of networked computer-controlled air vents, according to one embodiment of the invention; and  
         [0033]    [0033]FIG. 14 is a flowchart illustrating an algorithm used by the remote control device, according to one embodiment of the invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0034]    [0034]FIG. 1 illustrates the use of a computer-controlled air vent  10  used to cool or heat a structure  16 , according to one embodiment of the invention. The structure  16  is a residential or commercial building that includes a plurality of individual rooms, as well as one or more HVAC zones. Each HVAC zone includes one of the individual rooms, and each room includes one or more air duct outlets through which conditioned hot or cool air can flow to heat or cool the room as desired. One or more of the air duct outlets within a room may be equipped with the automatic computer-controlled air vent  10  shown in FIG. 1. As further described herein, the computer-controlled air vent  10  is remotely operated by a handheld or wall-mounted controller  14  located in the same room as the vent. The computer-controlled air vent  10  includes a force generating means and a renewable power supply that are self-contained within the air vent itself.  
         [0035]    Additionally, the computer-controlled air vent  10  is manufactured in a variety of sizes and configurations for fast and easy installation over existing air duct outlets in both residential and commercial buildings. The computer-controlled air vent  10  is made of a rigid material, such as plastic, wood, or metal, that can include a variety of colors and cosmetic appearances. Moreover, the computer-controlled air vent  10  can be manufactured to include a removable front plate. In such a configuration, the front plate can be removed for cleaning or swapped with a different front plate having the same or different color and/or aesthetic appearance.  
         [0036]    Although the computer-controlled air vent  10  may be installed in every room of a structure  16 , the air vent  10  is typically only installed in one more of the smaller rooms because these rooms tend to heat and cool faster than the larger rooms. As the HVAC unit blows conditioned hot or cool air into the one or more rooms that form an HVAC zone, the smaller room will reach a target temperature sooner than the larger rooms. The wireless remote controller  14 , which may be located at virtually any point within the smaller room, compares the room&#39;s ambient air temperature with the target temperature that was input into the wireless remote controller  14  by a user of the device. When the room&#39;s ambient air temperature approximately matches the target temperature, the remote controller  14  signals a force providing means disposed within the air vent  10  to close the vent&#39;s air louvers. Closing the louvers of course restricts the volume of conditioned air flowing through the air vent  10  and allows a greater portion of the available air to be diverted to other channels in the HVAC system. In this manner, more air is then provided to the larger rooms, which consequently heat or cool faster than would otherwise be the case. This, in turn, translates to energy savings and decreased operating costs because the HVAC unit now operates for shorter periods of time.  
         [0037]    The remote controller  14  is manufactured such that it can be held in the palm of a user&#39;s hand, positioned on a flat surface such as a desk, shelf, or table, or removably attached to a wall bracket. The remote controller  14  is powered by disposable or rechargeable batteries and includes various input buttons  18 , an optional display screen  20 , and a wireless radio-frequency transceiver, which is used to transmit control signals to the air vent  10 . The remote controller  14  does not replace nor control the central thermostat typically associated with the HVAC system. Rather, the central thermostat operates as normal. The remote controller  14  simply operates to monitor a user-specific target temperature for the room in which it is placed and to divert conditioned air to other channels of the HVAC system when the room&#39;s target temperature is reached, by signaling the force generating means to close the vent&#39;s air louvers. Furthermore, the remote controller  14  does not turn the HVAC unit ON or OFF. Instead, the HVAC unit takes all of its ON and OFF commands from the central thermostat as normal. Typically, the remote controller  14  will control only one corresponding air vent  10 . However, in some applications, such as where a single room includes two or more air vents  10 , a single remote controller  14  can be configured to control multiple air vents  10 .  
         [0038]    To prevent a remote controller  14  in one room from controlling the operation of an air vent  10  in another room, each remote controller/air vent pair may have a unique communications channel or communication code (such as is common with automatic garage door openers). To prevent a remote controller  14  connected to a corresponding air vent  10  from measuring the temperature in another room and controlling the air vent accordingly when the remote controller  14  transported to a room different than the one where the air vent is located, the remote controller&#39;s transceiver may be configured to have a limited operating range. For Bluetooth implementations, the remote is configured to send out a beacon and get a response from whichever vent is in the same room as the remote. In such an embodiment, the remote “knows” where it is and which vent to control.  
         [0039]    Alternatively, a remote controller  14  positioned in the same room as its corresponding air vent  10 , may be connected to a computer controlled network such as a LAN or WAN and operated by a user  12  at a remote location. As will be further described later, this embodiment is especially useful in conserving energy. For example, using this embodiment, a user  12  returning home late from work can program the remote controller  14  over the Internet or other network to delay the opening or closing of the air louvers to achieve the target temperature. Similarly, managers of commercial buildings can use the Internet or other network to program multiple remote controllers  14  installed in structures  16  located at distant geographical locations. Additionally, power companies can use embodiments of the present invention to prevent blackouts and other power shortages.  
         [0040]    The remote controller  14  is assembled from components known to persons of ordinary skill in the art using processes and techniques known in the art. Consequently, the various technical aspects of its product design and manufacture are not detailed here in order not to obscure the invention unnecessarily. The particular electrical and digital architecture of the remote controller  14  may vary according to the various commercial or residential application for which it is designed. In passing, however, the housing of the remote controller  14  is manufactured from a rigid material, such as wood, plastic, metal, and so forth, designed to have a particular color and/or pleasing aesthetic appearance.  
         [0041]    The remote controller  14  may execute a computer software program, which causes a graphical user interface (GUI) to be displayed in the display device  53 . From the information displayed on the GUI, a user can select a “manual override” function, an “on” function, an “off ” function, a “day” function, a “week” function, a “time of day” function, and a “target temperature” function. Selecting one of these functions causes a command signal to be output to a digital to analog (D/A) converter or to a wireless transceiver located within the housing of the remote controller  14 , which then transmits to the air vent  10  the proper signal sequence needed to implement the command over the wireless channel  22 . By selecting one or more of the “day”, “week”, “time of day”, and “target temperature” functions, a user  12  can program the remote controller  14  to operate at different time periods. This feature is especially useful where a room is used only during certain portions of a day or week, such as only during business hours Monday-Friday, or only on weekends.  
         [0042]    The remote controller  14  may also include a temperature sensing device in the form of a thermocouple or thermistor that senses the ambient air temperature of the room in which the remote controller  14  is located. This is particularly advantageous because the temperature of a particular room often differs from the temperature sensed by the distant HVAC thermostat. Additionally, the temperatures can differ significantly from one portion of the room to the next. For example, areas of the room above approximately shoulder height tend to be warmer than lower areas. Thus, a temperature that may be comfortable for persons standing within the room may be too cool for persons seated at desks. By making the remote controller  14  portable, it is possible to accurately sense the temperature at a particular area of the room, and to adjust the airflow accordingly. Thus, for example, a user sitting at a desk may place the remote controller  14  on the desktop, whereas a user standing for long periods, such as a dancer or an artist, may detachably mount the remote controller at approximately shoulder height on a wall of the room. Alternatively, the temperature sensing device can be located in the air vent  10  itself. If the air vent  10  is located near or in the ceiling or near or in the floor, algorithms known in the art can be used to calculate the temperature felt by a user standing or sitting in the room.  
         [0043]    [0043]FIG. 2 illustrates how one embodiment of a computer-controlled air vent  10  is retrofitted into an existing air duct outlet  31  of a conventional residential HVAC air duct  33 . Specifically, the base  46  slides within the interior of the air duct outlet  31 , and the face plate (hereinafter, top plate)  36  removably attaches either to a flange projecting from the perimeter of the air duct outlet vent  31  or to the wall, floor, or ceiling through which the air duct outlet  31  protrudes. When properly positioned, the top plate  36  substantially covers and conceals the outlet vent  31 . Moreover, the top plate  36  is of a size such that its flange  48  extends beyond a perimeter of the outlet vent  31  to maintain a substantially flush appearance without permitting the base  46  from being inserted too far into the outlet vent  31 . Screws or other fasteners inserted through the recesses  42  centrally formed at either end of the top plate  36  are used to secure the air vent  10  in place. It will be appreciated that the actual dimensions of the air vent  10  differ according to whether the air vent  10  is to be used in a residential or a commercial setting. For example, in residential settings, at least three different sizes of the air vent  10  may be used, which correspond to the three most common air duct outlet sizes used in residential homes.  
         [0044]    [0044]FIG. 3 and following illustrate one embodiment of a computer-controlled air vent  10  and the various component parts thereof. It will be appreciated that the embodiment shown is illustrative only, and that various other configurations included within the subject matter of the present invention are possible, but are not included here in order not to overcomplicate the invention.  
         [0045]    [0045]FIG. 3 is a front perspective view of a computer-controlled air vent  10 , according to one embodiment of the invention. The computer-controlled air vent  10  includes a top plate  36 , a base  46 , and a component housing  44 . Each of these major components is formed of a rigid material, such as plastic, wood, or metal. The component housing  44  is detachable from the generally rectangular-shaped base  46 . When viewed from the top or bottom, the base  46 , like the top plate  26 , has a hollow, generally rectangular shape.  
         [0046]    Fixedly or removably attached to the base  46 , the top plate  26  is larger than the base  46  and has a curved top surface that bows gently downward and outward from the longitudinal center axis  61  towards the edge portions  63 , as shown in FIG. 6. Portions of the top plate  26  that overhang the base  46  form the flange  48 , which was previously referenced in FIG. 2. The flange  48  may include one or more support ribs  50 , as shown in FIG. 4. Alternatively, the flange  48  may include no support ribs at all.  
         [0047]    Twin circular recesses  42  are formed in at either end of the top plate along the top plate&#39;s central longitudinal axis. Fasteners  38  in the form of screws fit though the recesses  42  to secure the air vent  10  to the air duct outlet  31 , as previously described.  
         [0048]    The grill  34  is a slatted, generally-rectangular air channel formed through the top plate  36 . The orthogonal intersection of the grill elements  32  and the stiffening bars  30  creates a square grid which diffuses air flowing through the air vent  10 . In embodiments of the invention where the air vent  10  is designed to be mounted on the floor, the grill elements  32  are manufactured to have an angled top portion  68  and a straight lower portion  70 , as shown in FIG. 6. In such an embodiment, the straight lower portion extends approximately ⅓ or greater into the depth of the base  46 . The combination of the angled portion  68  and the length of the straight lower portion  70  provide the rigidity and durability the top plate  36  needs to withstand the weight of an adult user without breaking. Computer-controlled air vents  10  designed to be mounted in walls or ceilings may have smaller grill elements  32 .  
         [0049]    A bubble  24  formed in a portion of the top plate  36  may house a wireless antenna or a temperature sensor.  
         [0050]    A removable component housing cover  26  is positioned adjacent one side of the grill  34 . A circular recess  40  is formed at each end of the component housing cover, and fasteners  41  in the form of screws fit through each recess  40  to detachably secure the component housing cover  26  to the air vent  10 . The component housing cover  26  may be removed to program the air vent  10  and/or to replace one or more batteries housed within the component housing  44 .  
         [0051]    As shown in FIG. 3, one embodiment of the invention includes a manual override switch  28  positioned between the grill  34  and the component housing cover  26 . Air louvers disposed within the base  46  are opened when the manual override button is slid in one direction and are closed when the button is slid in the opposite direction. The manual override button  28  may be omitted in other embodiments of the invention.  
         [0052]    [0052]FIG. 4 is a bottom perspective view of the computer-controlled air vent  10  of FIG. 3 further illustrating the base  46 , the optional support ribs  50 , the flange  48 , the grill elements  32 , and the component housing  44 . As shown, a pair of air louvers  62  and  64  are horizontally disposed within a bottom portion of the base  46 . The air louvers  62  and  64  are generally rectangular in shape and include one or more raised support ridges  65  (FIG. 5) extending along the lengths thereof. Pivots  66  (FIG. 5) centrally positioned in the first ends of the air louvers  62  and  64  rotatably fit within circular recesses  71  formed in an end wall  58  of the base  46 . Shafts centrally positioned in the other ends of the air louvers  62  and  64  extend through circular recesses formed in an end wall  60  of the component housing  44 . The air louvers  62  and  64  are shown in an open position in FIG. 4 and in a closed position in FIG. 5.  
         [0053]    [0053]FIG. 7 is a bottom perspective view of the air vent  10 , with the component housing  44  and the air louvers  62  and  64  removed. As shown, the support wall  60  forms one end of the base  46  and aligns with one side of the component housing opening  62 . Within the base  46 , are shown the grill elements  32  and the stiffening bars  30 .  
         [0054]    [0054]FIG. 8 is a perspective end view of the computer-controlled air vent  10  of the preceding figures, with the component housing  44  omitted from the drawing to show the electrical, mechanical, and digital components housed within the component housing cavity. Illustratively, such components include a force generating means  72 , a power source  74 , and cranks  96 . The force generating means  72  is mounted to the wall  60  on one side of the component housing cavity, and has a rotatable drive shaft connected to an upper portion of one of the cams  96 . The force generating means  72  is further connected to the power supply  74  and communicatively coupled to a computer processor mounted on a printed circuit board (PCB)  114  (shown in FIG. 9), which is positioned behind the power supply  74 . When commanded, the force generating means rotates the drive shaft, which also rotates the cams  96  connected to the drive shaft. If the cams  96  rotate clockwise, the louvers  62  and  64  connected to them will pivot into the open position of FIG. 4. If the cams  96  rotate in a counter-clockwise direction, the louvers  62  and  64  will pivot into the closed position of FIG. 5. In one embodiment, the force generating means  72  is a battery operated motor, a stepper motor, or a solenoid. In another embodiment, the force generating means is an artificial muscle of the type known to persons of ordinary skill in the art. For example, an artificial muscle generally is an ionic gel or electro-active polymer that expands and contracts when energized by a current source.  
         [0055]    The power source  74  includes one or more disposable or rechargeable batteries that are inserted and removed through the component housing opening  62  shown in FIG. 7. Specifically, before or after the computer-controlled air vent  10  is installed, a user disengages the fasteners holding the component housing cover  26  in place, removes the component housing cover  26 , and inserts or removes the batteries  74 . The user then repositions the component housing cover  26  and re-engages the fasteners to secure the cover  26  in place.  
         [0056]    [0056]FIG. 9 is a perspective view of a component housing  44 , according to one embodiment of the invention. The component housing  44  is a square-shaped, five-sided member that includes: a top member  80 , an opposing bottom member  88 , opposing side members  82  and  86 , a PCB  114 , and a back member (not shown) positioned behind the PCB  114 . The front side of the component housing  44  is left open to engage the wall  60 , previously described. In effect, the wall  60  forms the front side of the component housing  44 , when the component housing  44  is properly installed. A rectangular-shaped recess  76  is formed in the top member  80  to allow insertion and removal of the batteries  74  previously described. In use, the recess  76  is covered by the component housing cover  26 , previously described. A manual override switch housing  77  is connected to an upper surface of the top member  80 , and includes a recess  73  into which the manual override is slidably inserted. Within the cavity  78 , the various electrical, digital, and mechanical components previously described are arranged.  
         [0057]    [0057]FIG. 10 is an end perspective view of the mechanical linkage used to rotate the louvers  62  and  64  between an open and a closed position. As previously described, the linkage includes a motor  72  having a rotatable drive shaft  92  connected to the upper portion  130  of a cam  96  by a linkage bar  94 . The cams  96  are linked by the horizontal driver bar  102 . The cams  96  further include a hollow cylindrical base portion  108  and a lower arm  98 . Additionally, the force generating means  72  includes a housing having flanges  111  at the top and bottom ends. Recesses  112  formed within the flanges receive fasteners that connect to the wall  60  to support the motor  72  in a desired position.  
         [0058]    [0058]FIG. 11 is a perspective view of a louver assembly  5 , according to one embodiment of the invention. The louver assembly  5  is shown in an open position and includes the louvers  62  and  64 , the driver bar  102 , the cams  96 , and the motor  72 , as previously described.  
         [0059]    FIGS.  12 A- 12 D are side, cross-sectional, end, and top views of a cam  96 , according to an embodiment of the present invention. FIG. 12A is a side view of the cam  96 , which includes a cylindrical base member  108 , an upper portion  130 , and a lower portion  98 . When viewed from the side as shown in FIG. 12A, the cam  96  is substantially L-shaped, with the upper portion angling upwards and to the right of center, and the lower portion angling downwards and to the left of center. A recess  120  formed in the free end of the upper portion  130  connects to the linkage bar  94  previously described. A recess  122  formed just above a midpoint of the upper portion  130  connects to the driver bar  102 , previously described. An opening  128  is formed through the interior of the base  108  and includes two opposing ridge members  126  that protrude into the interior of the opening  128 . The upper and lower portions  130  and  98  are separated by an angle  91  of approximately 120 degrees.  
         [0060]    [0060]FIG. 12B is a cross-sectional side view of the cam  96  taken along the line A-A in FIG. 12A showing the placement of the upper portion  130  relative to the base  108 , the opening  128 , and the lower portion  98 .  
         [0061]    [0061]FIG. 12C is an end view of the cam  96 , again showing the positioning of the upper portion  130  relative to the base  108  and the lower portion  98 .  
         [0062]    [0062]FIG. 12D is a top view of the cam  96  further showing the geometrical relations between the upper portion  130 , the base  108 , and the lower portion  98 .  
         [0063]    The computer-controlled air vent  10  is advantageous for several reasons. First, the air vent  10  may be easily installed in existing HVAC outlet vents without hard-wiring the air vent  10  to a 110 V AC or to a 220 V AC source, or to various DC sources. Second, the computer-controlled air vent  10  accounts for such variables as people and equipment changes, external sun or snow loading, rain, daytime vs. nighttime needs, weekend vs. weekday needs, etc. Although possible to accommodate such changes manually, it is both time-consuming and often impractical for occupants of the structure  16  to repeatedly open and close the air vents by hand. Consequently, without the computer-controlled air vents  10 , uneven heating and cooling results, which consumes more energy than is needed to maintain a comfortable environment.  
         [0064]    Third, the computer-controlled air vent  10  works in conjunction with a central thermostat to cool or heat a structure  16  faster and more efficiently than conventional systems. Specifically, the computer-controlled air vent  10  distributes temperature-controlled air (the temperature of which is regulated by the thermostat) evenly to all areas of a structure (e.g. closing air vents when an area reaches a target temperature to redirect the temperature-controlled air to other areas of the structure that need it). This translates to significant energy savings.  
         [0065]    [0065]FIG. 13 is a perspective view of a system  140  for adjusting the temperature within a structure  16 . The system includes at least one computer-controlled air vent  10 , which is removably attached to an air duct outlet vent, and a corresponding handheld or wall-mounted remote controller  14 , as previously described. The remote controller  14  is connected to the air vent  10  via the wireless communications channel  22 . A HVAC unit  147  blows conditioned heated or cooled air through the air ducts  9  that run throughout the walls, floors, and ceilings of the structure  16 . The system  140  also includes a master controller  152 , connected to the remote controller  14  via the wireless communication channel  141 . The master controller  152  is connected to a computer network  144  such that a user of a portable computer  148  or a utility company  142  can selectively program the remote controller  14  from a separate geographical location. In one embodiment, the computer network  144  is a wide area network (WAN) such as the Internet. In another embodiment, the computer network  144  is a local area network (LAN). The communications links  143 ,  146 , and  150  may be physical cables in the form of a high speed fiber optic lines or DSL telephone lines. Alternatively, the communications links  143 ,  146 , and  150  may be wireless communications channels.  
         [0066]    In one embodiment, a power company  142  monitors energy consumption for one or more power grids and, from a remote geographical location, adjusts a target temperature in one or more remote controllers  14  (and master controllers  152 ) that are located in the homes or commercial buildings of participating users. Additionally, the power company  142  is configured and communicatively coupled to a structure&#39;s central thermostat to adjust a target temperature of the thermostat upwards or downwards. For example, target temperatures in one or more structures  16  may be adjusted upward a few degrees on hot days, or adjusted a few degrees downward on cold days. For example, the force generating means may open the louvers when the ambient air temperature and the inputted target temperature differ by a temperature of more than approximately 1.0 degrees Fahrenheit. Alternatively, the force generating means may close the louvers when the ambient air temperature and the inputted target temperature differ by a temperature of less than approximately 1.0 degrees Fahrenheit. These adjustments may be made manually or automatically in near real-time, and the target temperatures may be the same for all structures within a particular power grid or different for each structure. A time duration may be specified to limit the time the power company override remains in effect.  
         [0067]    The new target temperature (together with day/time/week information) is transmitted over the communications links  143  and  150  to the master controller  152 , which relays the new target temperature to the remote controller  14 . Once the new target temperature (and/or day/time/week information) is received, the remote controller  14  operates as previously described.  
         [0068]    In a similar fashion, an individual user of the personal computer  148  can adjust the target temperature (and/or day/time/week information) of a remote controller  14  upwards or downwards by inputting the new target temperature (and/or day/time/week) information into the personal computer  148  and transmitting the same over the communications links  146  and  150  to the master controller  152 , which then relays the inputted information to the remote controller  14 .  
         [0069]    The personal computer  148  may be a laptop computer, such as a G4 Powerbook™ manufactured by Apple Computer of Cupertino, Calif. Alternatively, the personal computer  148  may be a handheld device, such as a Palm OS organizer or a mobile phone.  
         [0070]    In another embodiment, a user can use the master controller  152  to adjust the target temperatures (and/or day/time/week information) of one or more remote controllers  14 . This embodiment is particularly advantageous where a plurality of remote controllers  14  are used within a single structure. In such an embodiment, the remote controllers  14  each transmit their respective actual and target temperatures (and/or day/time/week information) to the master controller over the communications channel  141 . These actual and target temperatures (and/or day/time/week information) are displayed for the user on a display device connected to the master controller  152 . Using an input device connected to the master controller  152 , the user can modify one or more of the target temperatures (and/or one or more of the day/time/week groupings). Once inputted, the new settings are transmitted from the master controller  152  to the respective remote controllers  14 . Thereafter, the remote controllers operate as described above.  
         [0071]    [0071]FIG. 14 is a flowchart illustrating one embodiment of an algorithm used by the remote control device  14  of FIG. 1. The algorithm  170  begins at block  172 , where it is determined whether a user input is received. If no user input is received, the remote control device  14  recalls a previously input target temperature (Block  180 ). If a user input is received, the remote control device  14  gets the inputted target temperature and stores it in a memory device located in the remote control device  14  (Block  174 ). Thereafter, a temperature sensing device located in the remote control device  14  provides a measured ambient air temperature of the room in which the remote control device  14  is located. A comparator in the remote control device  14  compares the input target temperature with the measured temperature (Block  176 ). If the measured temperature is equal to the input target temperature±approximately 3.0 degrees, the remote control device  14  sends a close command to the computer-controlled air vent  10 , which causes the force generating means to close the air louvers. If the measured temperature is not equal to the input target temperature±approximately 3.0 degrees, the remote control device  14  sends an open command to the computer-controlled air vent  10 , which causes the force generating means to open the air louvers. Thereafter, the algorithm  170  loops back to block  172 . An optional delay  185  may be included in the circuitry and logic of the remote control device  14  so that only periodic and not constant checks are made.  
         [0072]    As described above, one embodiment of the present invention includes an active louver positioning mechanism integrated within the vent  10  and includes a programmable control element  18  that recognizes the time of day, day of the week, and room temperature. The control element  18  can reside in the computer-controlled air vent  10  or remotely in the room in which the vent  10  is installed. The control element  18  provides a “close” or “open” signal to the louver positioning mechanism at the appropriate time(s) based on the control element&#39;s detection of time and the interior temperature. Both the louver positioning mechanism and the control element can potentially use power from a number of sources in the structure  16 . Illustratively, such power sources include airflow and electrical sources.  
         [0073]    Because a plurality of computer-controlled air vents  10  can be installed within a structure, each vent  10  is manufactured and configured to network with other computer-controlled air vents  10  and/or a master controller  152  configured to manage facility-wide environmental systems. The master controller  152  connects to a WAN in the form of the Internet to proved worldwide, real-time access to multiple facilities. Illustratively, this permits global control of an entire corporation for the optimization of energy usage and/or the remote servicing of internal customers. With such a system, corporations can react to energy rate changes on a real-time basis and work closely with energy providers to prevent shortages at peak periods of energy usage. In residential cases, the Internet link is used for power grid level control of energy consumption. Illustratively, residential customers are provided with a price discount for allowing an energy provider to have partial control of their heating and/or cooling systems, which aids significantly in reducing energy shortages.  
         [0074]    Embodiments of the present invention are applicable virtually anywhere a central heating/cooling system having multiple output points is used in a structure.  
         [0075]    One embodiment of a computer-controlled air vent  10  includes air deflection elements  32 , a louver control and actuation system  140 , a surrounding rim  48 , and the louvers  62  and  64  themselves. The rim  48  supports the vent  10  in a wall, floor, or ceiling. The air deflection elements  32  diffuse temperature-controlled air flowing through the vent  10 . The louver control and actuation system  140  monitors temperature, time, and a plurality of computer-controlled vents  10  on a local (or global) network. It also performs the closing and opening operations of the louvers  62  and  64  at the appropriate times. The surrounding rim  48  serves as a mounting surface for the register to cover the ducting port  31  into the room of interest. Elements of the system  140  are programmed by a user  12  to control the room temperature at certain times and to potentially block substantially all airflow into a room if it is not in use at other times. The computer-controlled air vent  10  can report its operational status, room temperature, and programming to a network that uses additional computers for both reporting and overall facility control purposes.  
         [0076]    Although the present invention is described herein with reference to a specific preferred embodiment, many modifications and variations therein will readily occur to those with ordinary skill in the art. Accordingly, all such variations and modifications are included within the intended scope of the present invention as defined by the following claims.