Patent Publication Number: US-6209792-B1

Title: Thermally actuated diffuser

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to air diffusers and more particularly pertains to a new thermally actuated diffuser for diffusing air and controlling room temperature without electrical apparatus. 
     2. Description of the Prior Art 
     The use of air diffusers is known in the prior art. More specifically, air diffusers heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements. 
     Known prior art includes U.S. Pat. No. 4,231,513; U.S. Pat. No. 4,509,678; U.S. Pat. No. 4,711,394; U.S. Pat. No. 4,570,850; U.S. Pat. Des. No. 331,102; and U.S. Pat. No. 2,257,007. 
     While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a new thermally actuated diffuser. The inventive device includes a housing having a first duct opening and a second duct opening. The second duct opening is diametrically opposed to the first duct opening to produce a substantially linear air path through an interior of the housing. The housing has a third exit opening wherein the third exit opening lies in a plane orientated substantially perpendicular to the first duct opening and the second duct opening. A damper blade for diverting air flow from the air path is positioned in the interior of the housing. The housing contains a first device and a second device which are both responsive to ambient temperature. The first and second devices each have first and second ends. The first end and the second end are adapted to move away from each other when the device is warmed and to move toward each other when the device is cooled. The first device is positioned in the interior of the housing adjacent to the air path so as to be struck by air flowing along the air path. The second device is positioned in the housing adjacent to the third exit opening so as to be surrounded by air entering the interior of the housing through the third exit opening. The first device is on one side of the damper blade and the second device is on the opposite side of the damper blade. A bracket assembly couples the first end of the first device to the first side of the damper blade such that a longitudinal axis of the first device is oriented substantially perpendicular to the air flow. A mounting assembly mounts the first device to the second device. The second device has a longitudinal axis oriented substantially perpendicular to the longitudinal axis of the first device. A hinge couples the second device to the mounting assembly. The damper blade has openings therein adapted to allow the mounting assembly to be movable relative to the pivot shaft, wherein the mounting assembly is movable between a warmed position and a cooled position of the first device. 
     In these respects, the thermally actuated diffuser according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of diffusing air and room temperature control without electrical apparatus. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing disadvantages inherent in the known types of air diffusers now present in the prior art, the present invention provides a new thermally actuated diffuser construction wherein the same can be utilized for diffusing air and controlling room temperature without electrical apparatus. 
     The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new thermally actuated diffuser apparatus and method which has many of the advantages of the air diffusers mentioned heretofore and many novel features that result in a new thermally actuated diffuser which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art air diffusers, either alone or in any combination thereof. 
     To attain this, the present invention generally comprises a housing having a first duct opening and a second duct opening. These openings are to be connected to a duct system that will supply a quantity of conditioned air to the first duct opening and remove a substantially similar quantity of air from the second duct opening. The second duct opening is diametrically opposed to the first duct opening to produce a substantially linear air path through an interior of the housing. The housing has a third exit opening wherein the third exit opening lies in a plane orientated substantially perpendicular to the first duct opening and the second duct opening. A damper blade, for diverting air flow from the air path, is positioned in the interior of the housing. The housing contains a first device and a second device which are both responsive to ambient temperature. The first and second devices each have first and second ends. The first end and the second end are adapted to move away from each other when the device is warmed and to move toward each other when the device is cooled. The first device is positioned in the interior of the housing adjacent to the air path so as to be struck by air flowing along the air path. The second device is positioned in the housing adjacent to the third exit opening so as to be surrounded by air entering the interior of the housing through the third exit opening. The first device is on one side of the damper blade and the second device is on the opposite side of the damper blade. A bracket assembly couples the first end of the first device to the first side of the damper blade such that a longitudinal axis of the first device is oriented substantially perpendicular to the air flow. A mounting assembly mounts the first device to the second device. The second device has a longitudinal axis oriented substantially perpendicular to the longitudinal axis of the first device. A hinge couples the second device to the mounting assembly. The damper blade has openings therein adapted to allow the mounting assembly to be movable relative to the pivot shaft, wherein the mounting assembly is movable between a warmed position and a cooled position of the first device. 
     There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. 
     In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. 
     As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. 
     Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way. 
     It is therefore an object of the present invention to provide a new thermally actuated diffuser apparatus and method which has many of the advantages of the air diffusers mentioned heretofore and many novel features that result in a new thermally actuated diffuser which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art air diffusers, either alone or in any combination thereof. 
     It is another object of the present invention to provide a new thermally actuated diffuser which may be easily and efficiently manufactured, marketed, and installed. The installation of the diffuser and housing is quicker and more airtight compared to existing models. 
     It is a further object of the present invention to provide a new thermally actuated diffuser which is of a durable and reliable construction. 
     An even further object of the present invention is to provide a new thermally actuated diffuser which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such thermally actuated diffuser economically available to the buying public. 
     Still yet another object of the present invention is to provide a new thermally actuated diffuser which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith. 
     Still another object of the present invention is to provide a new thermally actuated diffuser for diffusing air and room temperature control without electrical apparatus. 
     Yet another object of the present invention is to provide a new thermally actuated diffuser which includes a housing having a first duct opening and a second duct opening. The second duct opening is diametrically opposed to the first duct opening to produce a substantially linear air path through an interior of the housing. The housing has a third exit opening wherein the third exit opening lies in a plane orientated substantially perpendicular to the first duct opening and the second duct opening. A damper blade for diverting air flow from the air path is positioned in the interior of the housing. The housing contains a first device and a second device which are both responsive to ambient temperature. The first and second devices each have first and second ends. The first end and the second end are adapted to move away from each other when the device is warmed and to move toward each other when the device is cooled. The first device is positioned in the interior of the housing adjacent to the air path so as to be struck by air flowing along the air path. The second device is positioned in the housing adjacent to the third exit opening so as to be surrounded by air entering the interior of the housing through the third exit opening. The first device is on one side of the damper blade and the second device is on the opposite side of the damper blade. A bracket assembly couples the first end of the first device to the first side of the damper blade such that a longitudinal axis of the first device is oriented substantially perpendicular to the air flow. A mounting assembly mounts the first device to the second device. The second device has a longitudinal axis oriented substantially perpendicular to the longitudinal axis of the first device. A hinge couples the second device to the mounting assembly. The damper blade has openings therein adapted to allow the mounting assembly to be movable relative to the pivot shaft, wherein the mounting assembly is movable between a warmed position and a cooled position of the first device. 
     Still yet another object of the present invention is to provide a new thermally actuated diffuser that can be placed in existing duct work without a need for electrical wiring. This serves the valuable purpose of having the ability of installing additional temperature control equipment in older buildings where there is a need to retain structural integrity. 
     Even still another object of the present invention is to provide a new thermally actuated diffuser that can be modified for use of electricity if desired. 
     It is further object of the present invention to give near constant air throw from the grill face at variable supply volumes and temperatures by positioning the top of the damper blade at the slanting face of the housing top, to give constant supply plenum pressure, and the bottom of the damper blade over the supply grill blade follower to adjust the free area aperture of the grill to suit the air volume supplied to the room. 
     Still another object of the present invention is site adaptation of the supply grill which can be altered to suit changing office layouts. The blades of the grill can be changed to direct flow in differing patterns. 
     These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated preferred embodiments of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein: 
     FIG. 1 is a schematic front view of a grill for the present invention. 
     FIG. 2 is a schematic side view of a grill of the present invention. 
     FIG. 3 is a schematic top view of a second embodiment of a grill for the present invention. 
     FIG. 4 is a schematic front view of the housing of the present invention. 
     FIG. 5 is a schematic side view of the lid taken along the line  5 — 5  of the present invention. 
     FIG. 6 is a schematic side view of the box supports of the present invention. 
     FIG. 7 is a schematic frontal view taken along the line  6 — 6  of the box supports of the present invention. 
     FIG. 8 is a schematic side view of the housing of the present invention. 
     FIG. 9 is a schematic side view of the second embodiment of the grill of the present invention. 
     FIG. 10 is a schematic exploded view of the mounting assembly of the present invention. 
     FIG. 11 is a schematic exploded view of the second device of the present invention. 
     FIG. 12 is a schematic plan view of the second embodiment of the present invention. 
     FIG. 13 is a schematic frontal view taken along line  13 — 13  of the second embodiment of the present invention. 
     FIG. 14 is a schematic cross-sectional view taken along line  14 — 14  of the second embodiment of the present invention. 
     FIG. 15 is a schematic side view of the grill for the second embodiment of the present invention. 
     FIG. 16 is a schematic top view taken along line  16 — 16  of the grill for the second embodiment of the present invention. 
     FIG. 17 is a schematic sectional side view taken along line  17 — 17  of the present invention. 
     FIG. 18 is a schematic frontal view taken along line  18 — 18  of the present invention. 
     FIG. 19 is a schematic top view taken along line  19 — 19  of the present invention. 
     FIG. 20 is a schematic cross-sectional view of the thermally actuated devices of the present invention. 
     FIG. 21 is a schematic front view of the cowl and yolk of the present invention. 
     FIG. 22 is a schematic side view of the cowl and yolk of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With reference now to the drawings, and in particular to FIGS. 1 through 20 thereof, a new thermally actuated diffuser embodying the principles and concepts of the present invention and generally designated by the reference numeral  10  will be described. 
     As best illustrated in FIGS. 1 through 20, the thermally actuated diffuser  10  generally comprises a housing  12  having a first duct opening  13  for communicating with a first duct and a second duct opening  14  for communicating with a second duct. The second duct opening is diametrically opposed to the first duct opening to produce a substantially linear air path through the housing from the first duct opening to the second duct opening. The first and second ducts each lie in a plane substantially parallel to the plane of the other duct opening. The housing has opposing walls  15  positioned on either side of the air path. The housing has a third exit opening  16  for communicating with a room. The third exit opening lies in a plane orientated substantially perpendicular to the first duct opening  13  and the second duct opening  14 . The housing has a rebate  47  therein for facilitating an airtight fit between the housing and grill  27 . 
     A lid  17  on the housing has a proximal side  18  and a distal side  19 , wherein the proximal side  18  of the lid is positioned adjacent to an edge of the first duct opening  13 . The lid is preferably removable. The proximal side has a protuberance  20  extending toward the third exit opening. The protuberance is generally triangular in shape, and has an apex with an edge  21  extending therefrom. The protuberance helps create an airtight seal in the housing by allowing the damper blade  35  to run adjacent to it and thus prevent air from escaping out the second duct opening over the damper blade. Ideally, after manufacture, the lid is fixedly mounted to the housing to prevent the lid from falling away from the housing. 
     Two box supports  23  are used for supporting the housing within a wall. Ideally, the box supports can be places on any opposite sides of the housing. Each of the box supports comprises an elongate U-shaped channel spring shaft to grip the housing  12 . The housing  12  has opposite edges  24  on a side of the housing having the third exit opening. Each of the box supports is adapted to mount on one of the edges of the housing. The edges of the housing have two slots  25  therein for receiving the box supports The grip position of the support  23  on the housing is adapted to self-adjust to a position dependent on the wall thickness between the back of a grill  27  flange and the housing  12 . Such adjustment occurs as the edge of the grill  27  flange pulls onto the rebate  47  in the housing  12  and forms an airtight seal when tightened. 
     The grill  27  is utilized for directing airflow inwardly and outwardly of the third exit opening. The grill has dimensions adapted to fit across the side of the box that has the third exit opening  16 . The grill has a proximal side  28  and a distal side  29  and is oriented such that the proximal side of the grill is adjacent to an edge of the first duct opening  13  in the housing. The proximal side of the grill has rotatable eyelash vents  30  mounted thereon. The eyelash vents are oriented substantially perpendicular to the air path. And are preferably rotatable to direct outgoing airflow. The distal side of the grill has rectangular vents  31  therein. The grill is fastened to the box supports by a fastener means  32 . Ideally, the grill has a blade follower  26 . The blade follower has a concave surface directed toward the inside of the housing. The blade follower allows a damper blade  35  to run across it and create a more air tight seal to prevent air from leaking underneath the blade  35  as air travels from the first duct opening  13  to the second duct opening  14 . Screws travel through the wall and then the U-shaped box supports in order to create an air-tight fit against the wall. 
     A damper blade  35  diverts air flow from the air path. The damper blade is positioned in the interior of the housing  12 , and is positioned generally parallel to the first duct opening  13  in the housing. The damper blade has a first and second side, wherein the first side of the damper blade generally faces the first duct opening  13 . The damper blade is pivotally mounted in the interior of the housing for pivoting between a first position wherein substantially all of the air flow along the air path is diverted through the third exit opening  16  and a second position wherein the air flow along the air path is permitted to move along the air path without diversion of a significant amount of air flow through the third exit opening. Preferably, the damper blade has an upper side seal  48 , and a lower side seal  49 . The seals  48 , 49  extend from the blade and run against the sides of the housing to prevent air from traveling around the sides of the damper blade and out through the second duct exit. 
     A pivot shaft  36  is mounted to the damper blade for permitting rotation of the damper blade. The pivot shaft is mounted in the housing, and has opposite mounting ends. Each of the mounting ends is mounted to one of the opposing walls  15  of the housing. The mounting ends are mounted in pivot shaft bearings  33 . The pivot shaft is oriented substantially perpendicular to the air path between the first duct opening  13  and the second duct opening  14 . The pivot shaft is comprised of two separate elongate portions  37 ,  38  with an open expanse therebetween. Each elongate portion has an interior end  38  spaced from an interior end of the other elongate portion. The interior  38  end of each elongate portion is coupled to the damper blade  35 . The pivot shaft  36  is rotatable and adapted to allow the damper blade to rotate in the air path. 
     Two hole caps  39  are used for mounting a yolk  41 . Each of the hole caps is mounted on one of the spaced interior ends of the pivot shaft. Hole caps form seals over holes in the damper blade which will are necessary for reasons which will become readily apparent. The yolk has two elongate members  141 , wherein each of the elongate members is coupled to one of the spaced interior ends of the pivot shaft in hole caps such that the hole caps cover the ends of the elongate members of the yolk as they couple with the pivot shaft. The elongate members  141  extending outwardly from the hole caps parallel to each other in the direction of the second duct opening  14  of the housing  12 . 
     A first device  100  wherein the first device is responsive to the ambient temperature around the first device. 
     A second device  130  wherein the second device is responsive to the ambient temperature around the second device. 
     The first and second devices are generally elongate and each of the devices has a first end  101  and a second end  102 , wherein the first end and the second end are adapted to move away from each other when the device is warmed. The first end and the second end are adapted to move toward each other when the device is cooled. Wherein, the first and second ends are relatively extended away from each other in a warmed position and the first and second ends are relatively retracted inwardly toward each other in a cooled position. Each of the first ends  101  includes a piston shaft  103  and each of the second ends includes a cylinder  104  which has the piston shaft slidably received therein. The first device  100  is positioned in the interior of the housing adjacent to the air path so as to be surrounded by air flowing along the air path. 
     A bracket assembly  50  couples the first end  103  of the first device to the damper blade  35 . A first portion  51  of the bracket assembly is coupled to the piston shaft of the first device. A second portion  52  of the bracket is coupled to the damper blade  35  such that a longitudinal axis of the first device is substantially perpendicular to the air flow. The first device is positioned between the spaced ends  38  of the pivot shaft. 
     A mounting assembly mounts the first device  100  to the second device  130 . The first and the second devices are located on opposite sides of the damper blade  35 . The second device  130  has a longitudinal axis oriented substantially perpendicular to the longitudinal axis of the first device  100 . The second device  130  is positioned between the distal side of the lid  19  and the distal side of the grill  32  so as to be surrounded by air entering the interior of the housing through the third exit opening. 
     The mounting assembly  60  is comprised of a first plate  61  adjacent to the first device  100 . The first plate is longer than the cylinder  104  of the first device and has an L-shape with a long end  62  and a short end  63 . The short end of the L-shaped plate is affixed to the end of the first device where the piston shaft is located  103 , and the long end of the first L-shaped plate is parallel to the first device. The first plate is located between the first device and a first side of the damper blade. 
     A second plate  64  is located between the second device  130  and a second side of the damper blade. The second plate is oriented substantially parallel to the first plate. 
     A first coupling means  65  couples the first plate to the second plate. Preferably, the first coupling means is a bolt which is affixed to the end of the first device which extends through the first and second plates. The first coupling means is mounted to the second end of the first device. The first coupling means is orientated perpendicular to the long portion of the first plate  62 . The first coupling means extends through a bore in the first plate, a first spacer  71  mounted in a slot in damper blade  35 , and a bore in the second plate. 
     A second coupling means  66  with a second spacer couples to the first plate to the second plate and is located substantially at the intersection of a longitudinal line of the second device and the second plate. Preferably, the second coupling means is a rectangular plate  69  with a bolt  67  extending through each corner thereof. A nut  68  secures each of the bolts. 
     A hinge  70  couples the second device to the mounting assembly. The hinge is substantially centered on the second coupling means  66  and is fixedly coupled to the first plate between the first plate and the first device. The hinge is coupled to the piston shaft of the second device  131 , wherein the piston shaft of the second device extends through a bore in the first plate, the damper blade  35  and a bore in the second plate to couple to the hinge. 
     The damper blade has openings therein, not shown, adapted to allow the first plate  61  to be connected to the second plate  64  such that the mounting assembly is movable relative to the pivot shaft. The mounting assembly is movable between a warmed position and a cooled position of the first device. 
     The cylinder  104  of the first and second devices has a substantially hollow interior. The hollow interior is defined by an inner wall. A plug  105  is adjacent to the second end of the device. The plug has bore  106  therethrough. A sealing washer  107  is used to prevent the wax from moving against the plug. The sealing washer is adjacent to the plug. A wax fill cavity portion  108  is used for holding the wax. The cavity defined by the inner wall of the cylinder, the plug and an inner shuttle nut  113 . A return spring  110  has a first end adjacent to and biased against the spring base  109 . A piston shaft  103  extends away from the spring base through and out of the interior of the cylinder  104 . A shaft clip  111  retains the return spring  110 , the spring base  109  and the piston shaft  103 . A stop washer  112  is adjacent to and biased against a second end of the return spring. An inner shuttle nut  113  rests against the stop washer  112  and forms the top portion of the wax cavity. A shaft ‘O’ ring  114  is adjacent to the inner shuttle. A shuttle ‘O’ ring  115  is adjacent to the shaft ‘O’ ring. A shuttle  116  is adjacent to the shuttle ‘O’ ring. 
     An over-pressure spring  117  is adjacent to and extends away from the shuttle  116 . A compressor bottom  118  and a compressor top  119  are on either end of the over-pressure spring  117 . A cap  120  is placed adjacent to the compressor top  119  and is outside of the cylinder of the device. A pressure adjuster means  121  for adjusting movement of the shuttle  116  is affixed to the cap with a lock nut with the piston shaft  103  extending through a bore in the adjuster means and the cap  120 . The pressure adjuster means has a shaft stroke adjuster means  122  therein which is biased against a piston stroke stop  123  on the piston. 
     The second device is generally identical to the first device. The second device further uses its plug  135  for support. 
     A pin  136  is mounted in the bore in the plug and extends outwardly away from the plug. The pin forms a spring and bearing mount and has a first end  137  and a second end  138 . A first relief spring  139  is mounted on the spring mount. The first relief spring  139  rests against the plug  135 . A support bearing  140  is located at an apex of the first relief spring  139 . The support bearing is connected to the two elongate members  141  from the yolk  41 . The elongate members  141  extending horizontally and diametrically away from each other and from the support bearing. The elongate members bend to become parallel to each other to define the piston yolk  41 . The piston yolk  41  is coupled to and supported by the cowl  40 . The cowl  40  supports the second device. The cowl has a first side portion  42 , a second side portion  43 , and a top portion  44 . The first side portion  42  is coupled to one of the elongate members  141  of the yolk  41 , and the second  43  side portion is coupled to the other of the elongate members of the yolk. A second relief spring  142  is mounted on the spring mount. The second relief spring  142  has a first end adjacent to the piston yoke which is connected to the support bearing  140 . A stop washer  143  is affixed by a nut  144  to the second end of the spring mount. The pin  136  is coupled to the yolk  41  by the support bearing  140 . The cowl  40  extends toward the second duct opening  14  and rests inside that opening. 
     A quantity of wax is located in the wax fill cavities  108  of each of the first and second devices. The wax expands when subjected to additional thermal energy and contracts when thermal energy is removed. Any over expansion of the wax not required in the movement of the piston shaft  103  is absorbed by the over pressure spring  117 . The wax is preferably heat treated paraffin wax made by Bayliss Precision Components Ltd., Lydander Works, Blenheim Road, Airfield Induatial Estate, Ashbourne, Derbyshire, DE6 1HA England. 
     In use, the air diffuser is mounted into a wall or a ceiling within an air duct passageway. Two box supports  23  are used for supporting the housing within a wall or ceiling. The supports fit in slits or slots  25  on either edge  24  of the third opening  16 . The edges of the housing have two slots  25  therein for receiving the box supports. The box supports can be fastened into the wall or ceiling by any number of fastening means known in the art, though screws are preferred. 
     The grill  27  is utilized for directing airflow inwardly and outwardly of the third exit opening. The grill  27  is attached to the housing to cover the third exit opening. The grill is attached or fastened to the housing by a fastener means  32 . Preferably, the fastener means is a screw. The proximal side of the grill  28  has rotatable eyelash vents  30  mounted thereon. The eyelash vents are rotatable so that as air is spilled into the room, the user may change the direction of air flow. Eyelash vents are preferred over straight vents as cold air coming in through a ceiling would tend to fall directly downward if not directed into a circulation pattern. Another embodiment of eyelash vents, as best depicted in FIG. 9, show vents pointing in more than one direction for increased air diffusion. The distal side  29  of the grill has rectangular vents  31  therein. These vents allow air to enter the housing from the room and surround the second device. 
     Air comes through the first duct and through the first duct opening  13 . Depending on how the damper blade  35  is tilted, the air is either allowed to enter the room through the eyelash vents, or it is bypasses the eyelash vents and continues through the housing and out the second duct opening  14  or an intermediate position to maintain room temperature. The first device  100  is on the side of the damper blade facing the first duct opening  13  and is surrounded by air as it enters the housing through that duct. The second device,  130  is on the side of the damper blade  35  facing the second duct opening  14  and is surrounded by air which enters the housing through the third exit opening and leaving the housing by the second duct opening. 
     Both devices are comprised, primarily, of a cylinder  104  and a piston shaft  103 . The cylinder contains a wax filled cavity  108  which contains thermally sensitive wax. The wax expands as thermal energy is absorbed and contracts as thermal energy is released. The piston shaft  103  extends outward from the cylinder when the wax expands and the piston shaft retracts into the cylinder  104  when the wax contracts under pressure of the return spring  110 . The wax is contained in a compartment surrounded by the inner walls of the device  100 , a plug  105  and an inner shuttle nut  113 . 
     A bracket assembly  50  couples the piston shaft of the first device to the damper blade  35 . The first device is positioned between the spaced ends  38  of the pivot shaft  36 . Thus, when the piston  103  of the first device retracts or extends, the cylinder  104  moves relative to the pivot shaft  36  while the pivot shaft remains stationary. 
     A mounting assembly mounts the first device  100  to the second device  130  such that the cylinder of the first device directs the location of the hinge  70  and piston shaft of the second device  131  relative to the pivot shaft  36 . The mounting assembly is comprised of a first plate  61  and a second plate  64 . The plates are connected in two areas. The first area is located near the plug  105  of the first device. The second area is near a longitudinal midpoint of the cylinder of the first device. The first area binds the two plates, while the second area binds the plates with four bolts  67  and nuts  68  while at the same time created a place for a hinge  70  to which the piston shaft  131  of the second device  130  will couple. The first and second spacers stop plates  61  and  64  from gripping the damper blade  35 . 
     The damper blade has a rectangular opening between the two plates. This opening allows the plates  62  and  64  to move unrestricted within the plane of the damper blade  35 . Thus the brackets are movable relative to the pivot shaft  36  which allows the piston shaft  131  of the first device to move relative to the pivot shaft  36 . 
     The second device has an end which is coupled to a yolk  41 . The yolk allows the piston shaft  131  to move relative to the pivot shaft  36  while the second end  138  of the pin remains stationary. The yolk  41  and additional springs  139 ,  142  are employed with the second device to restrict pressure caused by the first device changing position while the second device is at either end of its stroke. FIG. 10 shows the hinge lower than the pivot shaft. The power of the wax expanding or contracting in the first device will force the second device to contract or expand as the hinge  70  moves relative to the pivot shaft  36 . This will ensure that the hinge can move from the lower side of the pivot shaft to a point higher than the pivot shaft without becoming jammed at point either higher or lower than the pivot shaft. 
     The first device  100  in the warmed position urges the mounting apparatus away from the bracket such that the hinge is oriented on a first side, or lower side as in FIG. 10, of the pivot shaft. The first device in the cooled position urges the mounting apparatus toward the bracket such that the hinge is oriented on a second side, or high side as in FIG. 10, of the pivot shaft. 
     The second device  130 , in the warmed position, urges its piston shaft  131  against the bracket assembly  60 . In the cooled position, the piston shaft  131  of the second device pulls the bracket assembly  60 . 
     There are four combinations of warmed and cold positions which rotate the blade. This allows the blade to rotate between fully open or closed positions or intermediate positions therebetween. 
     The warmed position of the first device  100  and second device  130  orients the blade damper  35  such that air flowing along the air path is directed toward the lid  17  and through the second duct opening  14 . 
     The warmed position of the first device  100  and the cooled position of the second device  130  orients the blade such that the air flowing along the air path is directed toward the eyelash vents  30  in the grill  27 . 
     The cooled position of the first device  100  and the warmed position of the second device  130  orients the blade such that air flowing along the air path is directed toward the eyelash vents  30  in the grill  27 . 
     The cooled position of the first device  100  and the second device  130  orients the blade such that air flowing along the air path is directed toward the second opening  14 . 
     FIGS. 12 through 16 best depict a second embodiment of the present invention. This embodiment functions nearly identical to the first. The primary difference between the two is that the second embodiment is made for only one duct. The first  100  and second  130  devices rotate the damper blade  35 , all of which are within a duct opening  145 . The damper blade is rotated to open and close the single duct opening  145 . The second device is mounted to a fixed plate  146 . The plate extends from the proximal corner of the lid to the center of the housing. At the center of the housing is a second pivot shaft  147 . This pivot shaft has a second damper blade  148  rotatably coupled to the second pivot shaft  147 . Attached to and extending away from the second damper blade is a weight  149 . 
     In use, as air enters the single duct  145  of the second embodiment, the first device contracts or expands, causing the piston shaft of the second device to move in relation to the first pivot shaft  36 . The second device  130  expands or contracts to the dictates of a room-mounted sensor, not shown, causing the damper blade to either allow air into the housing or closing the duct opening. The grill  150  for the second embodiment does not require a section of rectangular vents and only utilizes eyelash vents  151 . Due to damper blade  35  angle, there may be a large or a small volume of air entering the housing. The second damper blade  148  is coupled to a weight  149  which biases it into a position adjacent to the single duct opening  145 . As the first damper blade opens and the volume of air increases in the housing, and the second damper blade  148  is pushed away from the single duct opening. The weight keeps constant pressure against the air volume and ensures a constant air pressure to give a constant grill throw of air and circulate the air more effectively. 
     A third embodiment of the current invention utilizes electrical heating elements  125  placed on the outside of a single cylinder to control expansion and contraction of the wax. The elements would be operatively coupled to a thermostat which would be located on the housing in the air path or in the room being used. The heating elements could also be controlled from a central control either by remote control or standard methods. The second device  130  could also expand or contract due to a remote capillary was sensor (not shown). 
     A fourth embodiment, best depicted by FIGS. 5 and 8 of the current invention utilizes electric motors  126  that are coupled to the pivot shaft  36  which tilts the damper blade  35 . Sensors  127  would detect air temperature in the first duct opening  13  and the temperature in the room to determine if the damper blade will allow air from the first duct opening through the third exit opening  16 . This embodiment may also be operatively coupled to a thermostat or temperature sensor to manipulate blade rotation via a controller  127  positioned on the housing. 
     As to a further discussion of the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided. 
     With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. 
     Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.