Abstract:
A door assembly includes a door automatically operable relative to a floor and further comprises an electromechanical power device disposed beneath the floor and providing a rotary output on a shaft. The support apparatus includes a spindle adapted to receive power from the rotary shaft beneath the floor and to extend above the floor into a coupled relationship with the door. A bearing included in the support apparatus supports the spindle and at least a portion of the weight of the door beneath the floor. The electromechanical device can be of the type commonly used in overhead systems, in which case the power device can be retrofitted with the support apparatus for disposition beneath the floor. A coupling mechanism in the support apparatus can include pulleys, sprockets and gears, and power transfer devices such as belts and chains.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention related generally to automatic swing door operation systems and more specifically to electromechanical swing door operator assemblies used in such systems. 
     2. Discussion of the Prior Art 
     Swing doors capable of automatically opening and closing are required by many building codes. For example, such doors are commonly required in public buildings where they facilitate ingress and egress of people with respect to the building. These automatic systems are particularly appreciated by the handicapped as well as others whose hands are in use and therefore unavailable to mechanically open and close the door. Automatic swing door systems were originally manufactured for below-ground installation. These early systems were hydraulically controlled and required major underground plumbing of hydraulic tubing. Large remote locations were also required underground for an associated hydraulic sump and electronic controls. 
     These large and messy systems were soon obsoleted in favor of electromechanical swing door operators. However, these electromechanical swing door operators have only been used in overhead systems. A new generation of electrohydraulic swing door operators have also been solely adapted for overhead installation. 
     Overhead installations are undesirable for many applications. For example, historic buildings with antique doors need automatic systems in order to satisfy handicap access codes. Unfortunately, these buildings can only be accommodated with a significant alteration to the overhead configuration of the building. This significantly defeats the maintenance of the historic appearance. Other types of buildings, such as those including monumental glass systems, need an underground operator system to automate the door while maintaining the aesthetics of a “structure-free” glass system. In other cases, there simply is not sufficient overhead room to install a standard operator while maintaining minimum height codes. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, a swing door operation system includes an electromechanical operator and structural support assembly both of which are mounted beneath the surface of the floor. The operator provides sufficient power to open and close the door, but is not subjected to the axially weight or torque associated with the door. On the other hand, the structural assembly includes a spindle which is disposed beneath the floor surface but extends above the floor surface in a coupled relationship with the door. A first bearing plate is included in the support structure and adapted to receive a first bearing which supports the axial door load on the spindle. A second bearing plate is provided to receive a second bearing which opposes the lateral load on the spindle. A power transfer assembly is disposed between the first plate and the second plate and adapted to receive power from the electromechanical device and to transfer that power to the spindle for opening and closing the door. 
     The entire apparatus with the exception of the spindle, is mounting entirely beneath the floor surface where it does not interfere with the aesthetics of historic buildings or predominately glass structures. Furthermore, it is adapted to support the total weight of the door without damage to the electromechanical operator. Various transfer systems including pulleys, sprockets, gear, belts and chains can be employed to transfer power from the electromechanical drive to the spindle of the structural assembly. 
     In one aspect of the invention, a conversion assembly is adapted for use in an automatic door closing mechanism which includes a door pivotal on a vertical axis and an electrical power device which is adapted for use in an overhead door closure apparatus. This conversion assembly includes a support structure for pivotally supporting the door, and a first bearing plate included in the support structure and adapted to receive the weight of the door. A spindle having an axis extending between a first end and a second end is supported by the first bearing plate. A second bearing plate included in the support structure is disposed at the second hand of the spindle in a fixed relationship with the first bearing plate. A coupling mechanism in the support structure is disposed between the first bearing plate and the second bearing plate, and is coupled to receive power from the electrical power device to deliver that power through the spindle in the door to pivot the door about the vertical axis. 
     In another aspect of the invention, a door assembly includes a door automatically operable relative to a floor where the assembly comprises an electromechanical power device disposed beneath the floor and providing a rotary output on a shaft. A support apparatus including a spindle is adapted to receive power from the rotary shaft below the floor with the spindle extending above the floor in coupled relationship to the door. A bearing included in the support apparatus supports the spindle on at least a portion of the weight of the door beneath the floor. 
     In a further aspect of the invention, a method for constructing an automatic swing door operating system for use beneath a floor surface, comprises the steps of providing an electrical power device adapted for use in an over-the-door system. The method includes steps for providing a structural assembly adapted to support the weight of the door and configured to include a spindle rotatable about an axis. Coupling the electrical power device to the structural assembly facilitates rotation of the spindle by the device. The electrical power device is anchored together with at least a portion of the structural assembly beneath the surface of the floor and the door mounted on the spindle. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a double swing door system; 
     FIG. 2 is a top plan view of the door system of FIG. 1 illustrating open and closed positions; 
     FIG. 3 is a side elevation view of an underfloor door operating apparatus including sprockets and a chain; 
     FIG. 4 is a top plan view of the apparatus taken along lines  4 — 4  of FIG. 3; and 
     FIG. 5 is a side elevation view of a further embodiment of the door operating apparatus including a direct gear drive. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     An underfloor automatic swing door operation assembly is illustrated in FIG.  1  and is designated generally by the reference numeral  10 . The assembly  10  is adapted for use in automatically opening and closing a swing door  12  having a pivot axis  13 . The door  12  is adapted to fill a door opening  14  defined by a door jam  16  and floor  18 . The surface of the floor  18  is designated by the reference numeral  21 . 
     The door  12  is adapted for operation by the assembly  10  to move between a closed position  23  and an open position  25 . In the closed position, the door  12  is disposed in proximity to the door jam  16  and fills the opening  14 . In the open position  25 , the door  12  is displaced from the opening  14  to permit access for people and objects passing into or out of the associated building. 
     The operation assembly includes an electromechanical device  27  which converts electrical energy into mechanical rotary energy on an output shaft  29 . The assembly also includes a structural support apparatus  32  with a spindle  34  that pivotally supports the weight and torque of the door  12 . A power transfer unit  36  couples the output shaft  29  of the electromechanical device  27  to the spindle  34  of the structural support apparatus  32  in order to provide motive power for automatically opening the door  12 . 
     A cavity  41  is formed beneath the surface  21  of the floor  18  and provided with a size sufficient to receive and anchor the operation assembly  10 . With the exception of a portion of the spindle  34 , the entire operation assembly  10  including the electromechanical device  27 , the structural support apparatus  32 , and the power transfer unit  36 , is disposed within the cavity  41  beneath the surface  21  of the floor  18 . Accordingly, there is no automatic door operating assembly required above the door  12 . This makes the assembly  10  particularly desirable for historic buildings, glass monument structures and other environments where an overhead assembly would be aesthetically undesirable or mechanically impossible. The cavity  41  is generally of minimal size and does not require a hydraulic reservoir, large electronic equipment or significant plumbing associated with underfloor systems of the past. It only requires one conduit for power and one conduit for low voltage control. 
     The only overhead door structure required is a pivot pin  43  which extends on the pivot axis  13  between the door  12  and the door jam  16 . It will be noted that this pivot pin  43  does not need to support any of the weight associated with the door  12 . 
     Of particular interest to the present invention is the fact that the electromechanical device  27  can be of the type presently adapted for use in overhead swing door closure systems. In these systems, the electromechanical device  27  is not adapted to support the weight of the door. However, the device  27  typically includes an electrical motor  45  which is coupled to a transmission  47  having an output shaft such as the shaft  29 . The motor  45  and transmission  47  are generally disposed along a common longitudinal axis  49  with the output shaft  29  extending laterally, generally perpendicular of this axis  49 . 
     In accordance with one embodiment of the present invention, the electromechanical device  27  is adapted to function within the underfloor operation assembly  10 . A conversion unit  52  including the structural support apparatus  32  and the power transfer unit  36 , can be retrofit to the electromechanical device  27  and anchored within the underfloor cavity  41 . 
     In a preferred embodiment of the structural support apparatus  32 , a generally horizontal base plate  61  is coupled to an upstanding back plate  63 , and a gusset plate  65  which is generally parallel to the back plate  63  and perpendicular to the base plate  61 . A first bearing plate  67  is disposed in generally parallel relationship with the base plate  61  and supported by the gusset plate  65  and back plate  63 . The first bearing plate  67  is configured to receive a bearing  69  of the type commonly referred to as a support bearing or thrust bearing. 
     A second bearing plate is also coupled to the back plate  63  in generally parallel but spaced relationship to the first bearing plate  67 . The second plate  72  is sized and configured to receive a bearing  74  of the type commonly referred to as a lateral bearing. In this embodiment, the second bearing  72  has a top surface  76  which extends generally in the plane of the surface  21  of the floor  18 . A housing plate  78  disposed above the surface  21  of the floor  18 , aids in maintaining the lateral bearing  74  in the bearing plate  72 . 
     In the illustrated embodiment, the spindle  34  has an axis  81  extending between a first end  83  and second end  85 . The first end  83  is seated on the bearing  69  and supports all the weight and some of the torque associated with the door  12 . At the second end  85 , the spindle  34  is seated in the lateral bearing  74  where it supports some of the torque associated with movement of the door  12 . A spindle-to-door arm connector  87  is provided at the second end  85  and coupled to the door  12  along the axis  13 . Thus the axis  81  of the spindle  34  and the axis  13  of the door  12  are generally aligned, and the door  12  pivots in a generally fixed relationship with the spindle  34 . The pivoting of the spindle  34  is of course accommodated by the bearings  69  and  74  in the plates  67  and  72 , respectively. 
     As illustrated in FIG. 3, the electromechanical device  27  can be mounted on a support  89  connected to the base plate  61 . In a preferred orientation, the output shaft  29  of the transmission  47  extends upwardly in generally perpendicular relationship to the base plate  61  and surface  21  of floor  18 . In this upstanding orientation, the output shaft  29  has an axis  92  which is generally parallel to but spaced from the axis  81  of the spindle  34 . 
     With the electromechanical device  27  mounted on or retrofit to the base plate  61 , the power transmission unit  36  can be coupled between the output shaft  29  and the spindle  34 . This power transmission unit  36  can take many different forms, some of which include a rotary-to-linear converter  94  attached to the output shaft  29  and a linear-to-rotary converter attached to the spindle  34 . A linear-to-linear transfer device  98 , which preferably forms a continuous loop, can be used to couple the converter  94  to the converter  96  in order to transfer the motive power of the electromechanical device  27  to the spindle  34 . 
     In most cases, the converters  94  and  96  will be of the same type, and the transfer device  98  will be adapted to that type of converter. For example, in one embodiment, the converters  94  and  96  are in the form of pulleys having a typical circumferential cog belt pulley, and the transfer device  98  is in the form of a common cog belt. This same function can be accomplished with an embodiment wherein the converters  94  and  96  are in the form of gears having teeth. A complementary tooth belt can provide the transfer device  98  in this unit  36 . 
     In still a further embodiment illustrated in FIG. 4, the converters  94 ,  96  can be provided in the form of sprockets  112  and  114 , respectively. In such a unit, the transfer device is preferably provided in the form of a chain  116 . In any of these embodiments, the transfer device  98 , whether in the form of a belt  103  or  111 , or a chain  116 , can be provided with idler pulleys  118 ,  120  as illustrated in top view of FIG.  4 . 
     In another aspect of the invention, the power transfer unit  36 , the transfer device  98  takes the form of a pair of upstanding supports  121  and  123  which are mounted on an extension  125  of the first bearing plate  67 . The supports  121 ,  123  are adapted to receive a shaft  127  which is coupled at its opposing ends  129 ,  132  to a pair of beveled gears  134 ,  136 , respectively. In this embodiment, the converters  94 ,  96  are also provided in the form of beveled gears  138 ,  141 . In operation, the bevel gear  138  meshes with the bevel gear  134  to turn the shaft  127 . This also turns the bevel gear  136  which meshes with the bevel gear  141  to turn the spindle  34 . The cost of this embodiment may be greater than those previously discussed, but it provides a more direct drive and perhaps a quieter operation. Alignment of the power transfer unit  36  in either embodiment can be facilitated by providing the support  89  with properties for being adjustably fixed to the base plate  61  at an infinite number of positions relative to the back plate  63 . 
     It will be apparent that there are many variations on the foregoing embodiments which are all within the scope of this concept. For example, the operation assembly  10  can be provided either as a retrofit unit for an existing electromechanical device  27 , or the device  27  can be specifically adapted for the below floor mounted assembly  10 . In either case, the weight and torque of the door  12  is supported by a structural support apparatus  32  which is separate from the electromechanical device  27 . Accordingly, the device  27  is subjected only to the power requirements of the door  12  and spindle  32 . 
     Various other embodiments can achieve these same advantages. For example, the output shaft  29  can be oriented perpendicular to the spindle  34  with appropriate gearing provided in the power transfer unit  36 . Additionally, it will also be apparent that the converter  96 , although preferably disposed between the plates  67  and  72  can be coupled to the spindle  34  at any location along its length. In other variations, the converters  94 ,  96  may not be disposed in the same planar relationship as illustrated in FIG. 5, but may be disposed in a different relationship, for example where the bevel gears  134  and  136  are of different sizes. Particularly in the embodiment of 5 the converters  94 ,  96  and transfer device  98  can be formed from a variety of metal or plastic materials well known in the art. 
     Given these wide variations, which are all within the scope of this concept, one is cautioned not to restrict the invention to the embodiments which have been specifically disclosed and illustrated, but rather encouraged to determine the scope of the invention only with reference to the following claims.