Abstract:
A retractable vent system includes extendable portions that can be extended or retraced to position an inlet or outlet end of the vent at different locations. The extendable portion may be manually movable or power operated.

Description:
FIELD OF THE TECHNOLOGY 
       [0001]    The disclosed technology is related to heating and cooling systems used to heat and cool rooms of a building. 
       BACKGROUND 
       [0002]    Heating and cooling systems for buildings typically include a heating unit which produces heated air and a cooling unit which produces cool air. The hot or cool air is then delivered into rooms of a building through ducts and vents which open into the rooms. In addition, it is common to include air return vents and ducts which return air from one or more rooms of a building back to the heating unit or cooling unit. Thus, air is circulated from the heating and cooling unit, into the rooms, and then back to the heating and cooling unit. 
         [0003]    The placement of the vents which deliver heated or cooled air into a room, and the placement of return vents which pull air back out of a room can vary depending on the building design. It is common to place such vents in the walls of a room, in the floor of a room, or in the ceiling of a room. However, the position of the supply vents that deliver air into the room is typically fixed. Likewise, the position of return vents is also typically fixed. 
         [0004]    In large open buildings, such as hangers, large manufacturing facilities, and large retail stores, heating and cooling is typically accomplished by blowing heated or cooled air into the facility through vents positioned along the ceiling. In some instances, the vents may open into the facility below the ceiling, but still considerably higher than the people and structures located in the facility. There may also be return vents that draw air back out of the facility, and return it to a heating and/or cooling unit. Here again, however, the positions of the supply vents and the return vents is typically fixed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is a diagram of a first embodiment of retractable vents that are configured to conduct a cooling operation; 
           [0006]      FIG. 2  is a diagram of the retractable vents configured to conduct a heating operation; 
           [0007]      FIG. 3  is a diagram of the retractable vents illustrated in  FIGS. 1 and 2  configured to conduct a cooling operation; 
           [0008]      FIG. 4  is a diagram of a retractable vent that includes a drive unit for reconfiguring the vent; and 
           [0009]      FIG. 5  is a diagram of a second embodiment of retractable vents that are configured to conduct a cooling operation. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0010]    The inventors have discovered that a room can be heated and cooled more efficiently if the location of the vents supplying air into the room and the location at which air is withdrawn from the room is varied, depending on whether heated or cooled air is being delivered into the room. Based on testing, the inventors have determined that when a heating operation is being conducted, the highest efficiencies are obtained if heated air is delivered into the upper portion of the room while air is simultaneously withdrawn from the lower portion of the room. Conversely, if a cooling operation is being conduced, the highest efficiencies are obtained if the cooled air is delivered into the lower portion of the room, and air is simultaneously withdrawn from an upper portion of the room. This arrangement appears to run counter to traditional notions about how to achieve the greatest efficiency. 
         [0011]    Traditionally, those in the heating and cooling industry believed that during a heating operation, it would be better to deliver the heated air into the lower portion of the room, because that is the coolest location in the room. It was believed that doing so would result in the fastest increase in temperature in the room. Likewise, those in the heating and cooling industry believed that during a cooling operation, it would be better to deliver the cool air into the upper portion of the room, because that is the warmest portion of the room. It was believed that doing so would result in the fastest decrease in temperature in the room. 
         [0012]    The inventors have confirmed, however, that the temperature in a room can be increased more quickly if warm air is instead delivered into the upper portion of a room at the same time that air is withdrawn from the lower portion of the room. It is believed that this mode of operation more rapidly removes the coldest air from the room, which is located in the lower portion of the room. In addition, this appears to cause the entire mass of air to simply move gradually downward, with the relatively warm air in the center of the room moving downward to displace the cool air that is being withdrawn from the lower portion of the room. 
         [0013]    In a more traditional arrangement, where warm air is delivered into the lower portion of the room, the introduction of the warm air into the coldest portion of the room causes swirling and random mixing of the cool and warm air. Also, if air is simultaneously withdrawn from the upper portion of the room, this results in warmest air in the room being removed and sent back to the heater, which is inefficient. 
         [0014]    The same principles hold for cooling a room. If cool air is delivered into the lower portion of a room at the same time that air is withdrawn from the upper portion of the room, the warmest air will be immediately removed from the room. The relatively cool air at the middle portion of the room will rise upward to replace the air being removed from the room. Thus, the entire mass of air in the room will move gradually upward as cool air is introduced from the bottom, and the warmest air is removed from the top. 
         [0015]    The same principles that hold true for a single room also hold true for large open spaces, such as warehouses and large retail facilities. The greatest heating efficiencies are achieved if warm air is delivered from above at the same time that air is withdrawn from lower areas. For cooling, the greatest efficiencies are achieved if cool air is introduced from below, and air is withdrawn from above. Unfortunately, in most large temperature controlled spaces, heated and cooled air is delivered from fixed vents located in the upper part of the space. Likewise, air is withdrawn from the space through fixed vents that are also located at the upper part of the space. 
         [0016]    The inventors have developed a retractable vent system that can be used to deliver air into a space or remove air from the space. The retractable vent system can change its configuration so that it delivers air into the space or removes air from the space at varying heights. A retractable vent embodying the invention can be configured to deliver heated air into the upper portion of the space during heating operations. When it is necessary to switch over to a cooling operation, the retractable vent can be reconfigured to deliver cooled air into the lower portion of the space. Thus, a single retractable vent connected to a supply duct can vary the location at which it delivers air into the space depending upon whether heated or cooled air is being delivered, to thereby maximize the efficiency of the operation. 
         [0017]    In the same manner, a retractable vent embodying the invention could be used to withdraw air from a space during heating and cooling operations. During a heating operation, the retractable vent would be configured to withdraw air from a lower portion of the space while heated air is being delivered into an upper portion of the space. During a cooling operation, the retractable vent would be reconfigured to withdraw air from the upper portion of the space at the same time cool air is delivered into the lower portion of the space. 
         [0018]      FIG. 1  illustrates a first embodiment of retractable vents embodying the invention. Each retractable vent includes multiple nested sections that can be selectively extended or retracted to vary a length of the vent. By selectively varying the length of the vent, one can vary the location at which the vent discharges air into the space, or at which air is withdrawn from the space. Retractable vents as illustrated in  FIG. 1  could be attached to the ceiling of a large space, such as a warehouse or a large retail facility, or simply mounted in an upper portion of such a space. 
         [0019]    In  FIG. 1 , a supply duct  110  supplies heated and/or cooled air. The supply duct  110  would be connected to a heating and/or air conditioning system that generates heated and/or cooled air. In this embodiment, the supply duct  110  is connected to a first retractable vent  111  that includes a main body  112 , and five nested sections  113 ,  114 ,  115 ,  116  and  117 . Assuming the main body  112  of the retractable vent  111  is located in an upper portion of a space like a warehouse or a large retail facility, the nested sections can be extended, as shown in  FIG. 1 , so that the air supplied by the supply duct  110  is delivered to a lower portion of the space. 
         [0020]      FIG. 1  also illustrates that a second retractable vent  121  is connected to a return duct  120 . The return duct removes air from the space and conveys the air back to the heating and/or air conditioning system. The second retractable vent  121  also includes a plurality of nested sections that can be extended from the main body  122 . However, in the configuration illustrated in  FIG. 1 , the nested sections have all been retracted into the main body  122 .  FIG. 1  also illustrates that a vertical track  129  may guide upward and downward movement of the nested sections. A track  129  as illustrated in  FIG. 1  may or may not be present. 
         [0021]    When first and second retractable vents  111 ,  121  are coupled to a supply duct  110  and a return duct  120 , and configured as illustrated in  FIG. 1 , the vents could be used to perform an efficient cooling operation. As explained above, the most efficient cooling operations are achieved by delivering cool air into the lower portion of the space and simultaneously removing air from the upper portion of the space. 
         [0022]      FIG. 2  illustrates the retractable vents reconfigured to perform an efficient heating operation. The first retractable vent  111  that is connected to the supply duct  110  has been reconfigured by causing all the nested sections to be retracted into the main body  112 . Likewise the second retractable vent  121  that is connected to the return duct  120  has been reconfigured by having all of its nested sections  123 ,  124 ,  125 ,  126 ,  127  extend downward from the main body  122 . With this configuration, the most efficient heating operations can be performed, with heated air being delivered into the upper portion of the space through the first retractable vent  111  and air being simultaneously removed from the lower portion of the space through the second retractable vent  121 . 
         [0023]    When retractable vents as illustrated in  FIGS. 1 and 2  are used in a warehouse or a large retail space, and they are mounted on the ceiling or in the upper portions of the space, it may be desirable to configure one or the retractable vents so that its lowermost nested section is positioned partway between the lower portion of the space and the upper portion of the space, as illustrated in  FIG. 3 . In  FIG. 3 , the retractable vent  111  connected to the supply duct  110  is fully extended to the lower portion of the space. This means that the retractable vent is configured for an efficient cooling operation, where cool air will be delivered into the lower portion of the space, while air is simultaneously withdrawn from an upper portion of the space. 
         [0024]    In many warehouse and large retail spaces, the only portion of the space that must be temperature controlled is the lower portion, where people are located. The upper portions of the space are typically only filled with merchandise, goods or items that are being stored. For this reason, it is not important to ensure that the upper portions of the space are heated and cooled. In that instance, the retractable vent  121  connected to the return duct  120  can be lowered partway down so that its lowermost nested section  125  is located just above the location occupied by people. As result, cool air will be delivered into the lower portion of the space and air will be withdrawn from a part of the space mid way up the full interior height. 
         [0025]    When the system is configured at illustrated in  FIG. 3 , the temperature of the lower portion of the space, over the height Y, will be controlled, but the temperature of the upper portion of the space, along height X, is ignored. So long as the temperature within the Y height remains at a proper temperature, the people in the space will remain comfortable. And by running the system in this configuration, no money or resources are spent cooling or heating the upper portions of the space. This would not be possible with a traditional system where the vents are all mounted in the upper portions of the space. Thus, it would be impossible to conduct this type of an efficient heating or cooling operation with a traditional vent system. 
         [0026]    The nested sections or a retractable vent can be caused to extend from and retract back into the main body of the retractable vent via any type of mechanism. In some instances, the nested sections may be manually slidable with respect to each other so that a system operator can manually pull the nested sections out of the main body, or push them back into the main body. 
         [0027]    Friction alone can cause the nested sections to hold a particular configuration. Alternatively, latching mechanisms can be provided between each nested pair of sections to lock each inner section with respect to its adjacent outer section. The locking mechanism could hold an inner section at only a single predetermined position with respect to an outer section, or the locking mechanism could be configured to hold the inner section at any of an infinite number of different positions with respect to the adjacent outer section. 
         [0028]    In still other embodiments, a latching mechanism could hold some or all of the nested sections inside the main body, and releasing the latching mechanism would allow the unlatched sections to fall downward under the force of gravity. 
         [0029]    In still other embodiments, a powered drive unit may be provided to cause the nested sections to extend from and/or retract into the main body.  FIG. 4  illustrates one such embodiment. In this embodiment, three nested sections  133 ,  134 ,  135  are coupled to a main body  132  of the retractable vent  130 . A wire  138  that is connected to the innermost nested section  135  is wound around a shaft  137  of a motor  136  that is located in the main body  132  of the retractable duct  130 . Causing the shaft  137  of the motor  136  to rotate in a first direction causes the wire  138  to unwind from the shaft  137 , which allows the innermost nested section  135  to fall downward under the force of gravity. Continued rotation of the spool in the unwinding direction would allow the nested sections to gradually lower away from the main body  132 . Conversely, causing the shaft  137  of the motor  136  to rotate in the opposite direction would cause the wire  138  to wind up on the shaft  137 , and the innermost nested section  135 , and the intervening sections  134 ,  133  would be gradually retracted back into the main body  132 . 
         [0030]    In still other embodiments, a rack and pinion mechanism could be used to raise and lower the nested sections. The pinion gear would be connected to the rotating shaft of a motor, and the rack would be arranged on one or more of the nested sections. Other mechanisms for extending and retracting the nested sections could also be used, as will be apparent to those of ordinary skill in the art. 
         [0031]    In some embodiments, the cross-sectional shape of the nested sections could be circular. In alternate embodiments, the cross-sectional shape could be rectangular, square, triangular, oval, or have some other shape. 
         [0032]      FIG. 5  illustrates an alternate embodiment of a retractable vent system. In  FIG. 5 , a first retractable vent  140  is attached to a supply duct  110 , and a second retractable vent  150  is attached to a return duct  120 . The first retractable vent  140  includes a rotating spool  144  mounted in a main body  141 . The rotating spool  144  is coupled to the supply duct  110  via a coupling  146  so that heated/cooled air delivered by the supply duct  110  is delivered into the spool  144 . In addition, an extendable vent line  142  is wound around the exterior of the spool  144 . One end of the extendable vent line  142  is coupled to the spool  144  so that heated/cooled air delivered into the spool is conveyed into the extendable vent line  142 . The opposite end of the extendable vent line  142  discharges the heated/cooled air into the space. 
         [0033]    The second retractable vent  150  has the same basic features and it is coupled to the return duct  120  in the same fashion. As a result, air is withdrawn from the space from an end of the extendable vent line  152 , and the air is conveyed into the spool  154 , and then into the return duct  120 . 
         [0034]    In the embodiments illustrated in  FIG. 5 , the extendable vent lines  142 ,  152  can be extended to any desired height within the space to accomplish efficient heating and cooling operations. In the embodiment illustrated in  FIG. 5 , the retractable vents are configured for an efficient cooling operation, where cool air will be supplied into a lower portion of the space through the first extendable vent line  142 , and air will be simultaneously withdrawn from the upper portion of the space through the second extendable vent line  152 . 
         [0035]    In some embodiments, the extendable portion of the vent could extend and retract through free space. In alternate embodiments, the extendable portion could be coupled to a vertical track that guides upward and downward movement. Also, in some embodiments, a protective frame may extend vertically along the path that the extendable portion travels from the retracted to the extended positions. The frame would prevent people or objects from contacting and damaging the extendable portion, and from blocking its path when it is extending. The frame would be largely open, so that air can freely move into and out of the lowermost part of the extendable portion, regardless of its vertical position.  FIG. 5  also illustrates that the first and second extendable vent lines  142 ,  152  travel inside open frames  148 ,  158  that provide protection from damage, but which allow the free flow of air into and out of the vent lines. 
         [0036]    While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.