Patent Publication Number: US-6210269-B1

Title: Oscillating drive for air flow discharge

Description:
TECHNICAL FIELD 
     The invention generally relates to air distribution units of the type commonly used in air conditioning, heating or ventilation systems and, more particularly, to a drive mechanism for an oscillating discharge louver assembly for such a unit. 
     BACKGROUND ART 
     In many commercial air conditioning, heating and ventilating systems, treated air is discharged into an area to be conditioned through an air distribution or conditioning unit. For example, one general type of air conditioning system, often referred to as a split system, includes separate indoor and outdoor units. The outdoor unit includes a compressor, a heat exchanger and a fan. The indoor unit includes a heat exchanger and a fan. In operation, the indoor fan draws air into the indoor unit, through an inlet thereof, and forces the air over the indoor heat exchanger and then out of the indoor unit, through an outlet opening therein. 
     The outdoor fan draws air into the outdoor unit, through an inlet, forces that air over the outdoor heat exchanger and then forces that air out of the outdoor unit through an outlet therein. At the same time, a compressor causes a refrigeration fluid to circulate through and between the indoor/outdoor heat exchangers. At the indoor heat exchanger, the refrigerant absorbs heat from the air passing over that heat exchanger, cooling that air. At the same time, at the outdoor heat exchanger, the air passing over the heat exchanger absorbs heat from the refrigerant passing therethrough. Typically, a louvered assembly is disposed in the outlet of the indoor unit to direct the air discharge from that unit at a preferred angle. 
     It is considered desirable for the louvered air discharge to be provided with an arrangement whereby the louvers are oscillated to vary the direction of air flow from the discharge assembly. 
     DISCLOSURE OF THE INVENTION 
     An oscillating drive mechanism for an air discharge nozzle, which is mounted for pivotal movement about an axis. The discharge nozzle includes end plates, each having a pivot pin extending along the pivot axis. One end plate has an elongated slot therein spaced from the pivot pin. The pivot pins are supported at opposite ends by support structure, which allows pivotal movement of the nozzle about the axis. The support structure adjacent one end includes an opening therethrough spaced from the axis and configured such that the elongated slot and one end plate will sweep across the opening as the air discharge nozzle pivots through a predetermined desired arcuate sweep. A drive motor having a drive axis is attached on the opposite side of the support structure, opposite the through opening. A drive mechanism is disposed in the opening. The drive mechanism is coupled to the drive motor on one side thereof and has a drive pin on the other side thereof, which is driven in an orbiting pattern around the motor drive axis. The drive pin is configured to engage the elongated slot in the end plate and to traverse the slot in alternating directions as the motor rotates the drive mechanism to thereby cause the air discharge nozzle to oscillate through the predetermined arcuate sweep. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention may be better understood and its objects and advantages will become apparent to those skilled in the art by reference to the accompanying drawings, in which: 
     FIG. 1 is a perspective view of the indoor unit of an air conditioner which embodies the features of the present invention; 
     FIG. 2A is a perspective view showing the unit illustrated in FIG. 1 with the left side cover and one of the front modular panels removed therefrom; 
     FIG. 2B is an enlarged perspective view of the upper left-hand corner of the unit of FIG. 2A showing the drive motor and oscillating drive element exploded therefrom; 
     FIG. 3 is an enlarged perspective bottom view showing the air flow discharge assembly of the air conditioning unit of FIG. 1 with the louvers removed therefrom to show detail of the drive mechanism; 
     FIG. 4 is an enlarged view showing the detail identified as FIG. 4 in FIG. 3; 
     FIG. 5 is an exploded view illustrating the engagement between the oscillating drive element and louver assembly of FIG. 3; 
     FIG. 6 is an exploded perspective view of the air conditioning unit of FIG. 1; 
     FIG. 7 is an enlarged view of a modular front panel of the unit of FIG. 1; 
     FIG. 8 is an enlarged top view of the front panel of FIG. 7 with the louver assembly and the motor and oscillating drive element exploded therefrom; and 
     FIG. 9 is a simplified side view of an outer cover assembly showing the range of motion of the louver assembly and the orientation of the drive element with respect to the louver assembly. 
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION AND INDUSTRIAL APPLICABILITY 
     Looking first at FIGS. 1 and 6, the indoor unit  10  of a split system air conditioning system of the type incorporating an oscillating drive for the air flow discharge louver assembly according to the present invention is illustrated. Briefly, the unit  10  includes a main structural support frame  12 , which includes a bottom panel  14 , a back panel  16  and a top section  18 . Attached to the sides of the back and top panels are structural internal side covers  20 . The side covers  20  and the back panel  16  cooperate to support a horizontally extending fan support panel  22 , which includes a pair of rectangular openings formed therein. Mounted above the fan support panel  22  on a pair of inclined surfaces  26 , defined by the internal side covers  20  is a heat exchanger coil  25 . 
     Mounted under the top section of the main support frame  12  is an upper condensate collection pan  28 . Mounted in the front of the unit, under the bottom of the heat exchanger  25 , and supported by the front edge  30  of the fan support panel  22 , is a lower condensate collection pan  32 . A front section of the lower condensate collection pan extends upwardly and is spaced from the heat exchanger coil  25 . 
     Mounted to the lower surface of the fan support panel  22  is a fan assembly  34 , which includes an electric motor  36  adapted to drive a pair of centrifugal fans  38 , which are each enclosed in a two-piece scroll housing  40 . Each of scroll housings  40  defines a rectangular upper air outlet opening  39 , which is in air flow communication with the rectangular openings  24  in the fan support panel  22 . 
     As a result of the above-described arrangement of components, when the fan assembly is energized, air is drawn into the region  41  underlying the fan support panel  22  through the open front and is directed upwardly through the rectangular openings  24 , through the heat exchanger coil  25  and is discharged through an opening  42  defined by the upper edge  44  of the lower condensate pan  32  and the front edge  46  of the upper condensate pan  28 . 
     Reference numeral  48  refers generally to a front and top cover section assembled from two separate modular panels, which form the subject matter of an invention disclosed and claimed in another application assigned to the assignee of the present invention and filed on even date herewith. Each modular panel  50  generally includes a planar front section  52 , which includes a lower louvered portion  54 , which is in fluid flow communication with the region  41  underlying the fan panel to thereby define the air inlet to the unit. A solid section  56  of the planar front panel overlies a planar front section  58  of the lower condensate pan  32 . Extending rearwardly from the upper end of the planar front section  52  of each modular panel  50  is a top section  60 , which defines a rectangular air discharge opening  61 , which overlies the discharge opening  42  described hereinabove. The top section  60  also includes a substantially horizontally extending section  62 , which overlies and covers the top  18  of the main structural support frame  12 . 
     The front cover  48  is attached to the unit by means of threaded fasteners interconnecting the upper horizontal section  62  with a flange  64  on the top  18  of the main structural support, and by additional threaded fasteners interconnecting the front cover with a flange  66  on the front of the fan panel  22  and a flange  68  provided on the front of bottom  14  of the main structural support. Left and right external side covers  70  and  72 , respectively, are suitably attached to the internal side covers  20  and the left and right-hand sides of the cover assembly  48 . 
     As best seen in FIGS. 7 and 8, an air discharge louver assembly  74  is adapted to be mounted within the rectangular air discharge opening  61  of each of the modules  50 . Each louver assembly  74  comprises an elongated air directing housing  76  having left and right end walls  78  and  80 , respectively, which in turn are interconnected by an elongated longitudinally extending upper wall  82  and a longitudinally extending lower wall  84 . Mounted within the housing  76  and extending vertically between the upper and lower walls  82  and  84  are a series of flat pivotally mounted air deflectors  86 , which are arranged to be manually displaced in a left to right orientation to thereby direct the flow of air thereby, as is conventional. 
     The left and right end walls  78  and  80  are each provided with a centrally located pivot mount pin  88 . As best seen in FIG. 8, the rectangular air discharge opening  61  is bounded by left and right side walls  90  and  92 , respectively. Each of these walls is provided with a pivot pin receiving structure  94 , which is adapted to receive the pivot pins  88  of the left and right end walls  78  and  80  in a snap-fit fashion, which allows free pivoting of the louver assembly  74  about the pivot pins once installed to these receiving structures. Once installed in this relationship within the air discharge opening, the discharge flow of air passes through the louver assembly housing  76  as it exits from the air conditioning unit. 
     As best seen in FIG. 9, the indoor unit  10  is provided with a louver assembly oscillating mechanism, which is adapted to oscillate the louver assembly housing  76  between a first position, as indicated in solid lines in FIG. 9, to a second position as indicated in phantom lines in FIG.  9 . The oscillating mechanism when actuated will cause the housing to oscillate continuously between these two positions. 
     The oscillating mechanism includes an elongated slot  96  positioned in left-hand end wall  78  of the louver assembly housing  76 . The slot  96 , has a longitudinal axis, which intersects with the axis of the pivot pins  88 . As best seen in FIGS. 2B,  8  and  9 , a circular through opening  100  is provided in left-hand side wall  90  of the air discharge opening  61 . The circular opening  100  is located rearwardly and downwardly from the pivot pin  88  axis and, as best seen in FIG. 9, is sized such that the elongated slot  96  will sweep between the position shown in phantom lines and identified as position “A” when the louver housing  76  is in the extreme clockwise position in FIG.  9  and to the position identified as position “B” when the louver housing  76  is in the extreme counter clockwise position. 
     As best seen in FIGS. 4 and 5, an oscillating drive element  102  having a main circular section  104  and a crank pin  106  mounted on the outer periphery thereof is adapted to pass through the opening  100  with the crank pin  106  sized to be slideably received within the slot  96  in the louver housing  76 . Mounted on the other side of the main circular section  104  of  10  the oscillating drive element  102  is a centrally located drive shaft receiving socket  108 . 
     Mounted on the outer surface  110  of the left side wall  90  is a synchronous motor  112  having a reduction gear drive having an output shaft  114  adapted to be received in the drive socket  108  of the oscillating drive element  102 . The motor  112  is mounted by suitable threaded fasteners  116  passing through mounting flanges  118  and received in axially aligned openings  120  in the outer surface  110  of the side wall  90 . 
     The output speed of the synchronous motor is on the order of several revolutions per minute and is continuous in the same rotational direction. Continuous actuation of the motor  112  will result in rotation of the oscillating drive element  102  and orbiting of the crank pin  106  about the central axis of the oscillating element  104 . Such motion of the crank pin will cause the pin to translate back and forth within the slot  96  thereby driving the louver assembly housing  76 , through the end wall  78 , between the positions illustrated in FIG. 9, as described above. 
     While the oscillating drive mechanism has been described in connection with driving a single louver assembly  74  mounted in a single modular panel  50 , it should be appreciated that it is capable of driving several interconnected louver assemblies. As best seen in FIG. 6, where two modular panels  50  are shown interconnected, each panel is provided with its own air discharge opening  61 , which is bounded by left and right side walls  90  and  92 . Each of these sets of side walls  90  and  92  is provided with the above-described pin receiving structure  94  and is adapted to receive mating pins  88  of the louver assembly  74  therein. Adjacent louvers are interconnected in series fashion by pin and socket assemblies. As best seen in FIG. 8, the left-hand end wall  78  of each louver assembly is provided with a pin  122  extending outwardly therefrom adjacent to and underlying the upper wall  82 . As best seen in FIG. 3, the right-hand end wall  80  of each louver assembly housing  76  is provided with a socket  124  located under the upper wall  82  thereof and in axial alignment with the pins  122 . Accordingly, two or more adjacent louver assemblies may be interconnected and driven by a single oscillating drive mechanism.