Patent Abstract:
A roll-up curtain assembly includes plural, vertically spaced, horizontal roll-up rods extending across an opening. Each roll-up rod is coupled to a respective flexible curtain section and an electric motor. Actuation of the electric motor in a first direction of rotation causes rotation of the roll-up rod in a first direction for rolling the flexible curtain section onto the rod and moving the curtain assembly to the retracted, or open, position. Actuation of the electric motor in a second, opposed direction of rotation lowers the roll-up rod resulting in an unwinding of the curtain section from the rod allowing the curtain assembly to assume the extended, or closed, position. Plural vertically spaced curtain sections each having a respective motor/roll-up rod combination are coupled together and move upward or downward in unison.

Full Description:
FIELD OF THE INVENTION 
     This invention relates generally to movable partitions or walls such as in a building structure and is particularly directed to a multi-section roll-up curtain assembly. 
     BACKGROUND OF THE INVENTION 
     Flexible doors of the general type wherein a drive mechanism for raising and lowering the door includes an electrically powered motor which applies torque to a roller causing the door to wind up on or to unwind from the roller in positioning the door in either the open or closed position, or any position therebetween. The flexible curtain is typically comprised of a lightweight, strong fabric material and the electric motor is typically connected to the roller mechanism via a reduction gear to reduce the number of revolutions of the electric motor per unit distance of travel of the flexible door. Movable structures of this type can be used either to cover an opening, such as a doorway in a building structure, or they be used as a movable partition, or curtain, in the structure. 
     When used as a partition, or curtain, this roll-up structure may span large distances in the building structure. These types of flexible curtains isolate the inside of the building structure from the elements, such as wind, rain, snow and sunlight, while permitting the building structure to be opened up so as to provide access to the outside when the environment is more hospitable. 
     As the applications for these types of flexible curtains have increased, additional demands have been placed on their structure and operation. For example, these types of flexible curtains are being used to span increasingly longer distances within the building structure. This, of course, places increasing demands upon the curtain support and drive, or displacement, system. Higher power ratings are required for the curtain drive mechanism, which typically includes an electrically powered motor, for increasing heights and horizontal distances spanned by the curtain. In addition, the curtain support system, which typically is in the form of a horizontal, elongated rod, must be stronger to accommodate the increased weight of curtains spanning larger openings and must itself be lightweight to compensate for the increased weight of the curtain. This further increases the power requirements to operate the flexible curtain. Where a roll-up rod is attached to a lower end of the flexible curtain, a complicated displacement and support mechanism is typically required to accommodate vertical movement of the rod. 
     The present invention addresses the aforementioned limitations of the prior art by providing a multi-section roll-up curtain assembly including plural, vertically spaced, horizontal roll-up rods each extending across an opening and attached to a respective section of the curtain. Each of the rods is coupled to and rotated by a respective electric motor, with the electric motors connected and vertically displaced with the curtain either upward or downward in retracting or extending the curtain sections in unison. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide a multi-section roll-up curtain for use as a partition or wall in a building structure which is capable of spanning a large distance. 
     It is another object of the present invention to provide a multi-section roll-up curtain including plural bi-directional drive motors coupled together and arranged in a vertically spaced manner, with each motor coupled to a respective curtain section to permit the motors and curtain sections to move upward or downward in unison in opening or closing the curtain. 
     Yet another object of the present invention is to reduce the power required to operate a large roll-up curtain covering a large horizontal span and height. 
     A further object of the present invention is to incorporate plural vertically spaced, elongated horizontal members in a roll-up curtain to strengthen the curtain and make it more resistant to wind damage without increasing the power required to open and close the curtain. 
     The present invention contemplates a roll-up curtain comprising a first curtain section including a first fixed upper rod attached to a support structure and a second lower rod; a second curtain section in vertical alignment with the first curtain section and including a third fixed upper rod attached to the support structure and a fourth lower rod, wherein the second curtain section is disposed below the first curtain section; a first rotary drive coupled to the second lower rod for rotationally displacing the second lower rod in a first direction for rolling up the first curtain section onto the second lower rod, wherein the second lower rod is displaced upward toward first fixed upper rod in opening the first curtain section, or for rotationally displacing the second lower rod in a second opposed direction for unrolling the first curtain section from the second lower rod in closing the first curtain section; a second rotary drive disposed below the first rotary drive and coupled to the fourth lower rod for rotationally displacing the fourth lower rod in a first direction for rolling up the second curtain section onto the fourth lower rod, wherein the fourth lower rod is displaced upward toward the third fixed upper rod in opening the second curtain section, or for rotationally displacing the fourth lower rod in a second opposed direction for unrolling the second curtain section from the fourth lower rod in closing the second curtain section; and a coupling arrangement for connecting the first and second rotary drives wherein the first and second rotary drives move upward in unison when the second and fourth lower rods are displaced upward in opening the first and second curtain sections, and wherein the first and second rotary drives move downward in unison when the second and fourth lower rods are displaced downward in closing the first and second curtain sections. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The appended claims set forth those novel features which characterize the invention. However, the invention itself, as well as further objects and advantages thereof, will best be understood by reference to the following detailed description of a preferred embodiment taken in conjunction with the accompanying drawings, where like reference characters identify like elements throughout the various figures, in which: 
         FIG. 1  is a perspective view of a roll-up curtain assembly in accordance with the present invention shown in the full closed position; 
         FIG. 2  is a perspective view showing the roll-up curtain assembly of  FIG. 1  in a partially open position; 
         FIG. 3  is a perspective view of a support and drive arrangement for raising and lowering the roll-up curtain assembly of the present invention; 
         FIG. 4  is a partial perspective view of plural curtain sections of a roll-up curtain assembly in accordance with one embodiment the present invention; 
         FIG. 5  is a side elevation view shown partially in section of a multi-section, roll-up curtain assembly in accordance with the present invention; 
         FIG. 6  is a partial sectional view of a portion of a support structure for use with the roll-up curtain assembly of the present invention; 
         FIG. 7  is a plan view of a pair of drive motors each connected to a respective moveable support rod attached to a respective curtain section for raising and lowering the curtain sections in unison; and 
         FIGS. 8 and 9  are respectively exploded and perspective views of a drive mechanism for raising and lowering a roll-up curtain assembly in accordance with one aspect of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to  FIG. 1 , there is shown a perspective view of a roll-up curtain assembly  10  in accordance with the present invention shown in the extended, or closed, position.  FIG. 2  is a perspective view of the inventive roll-up curtain assembly  10  in the retracted, or upraised, position. 
     The roll-up curtain assembly  10  includes an upper curtain  12  and a lower curtain  14 . The upper and lower curtains  12 ,  14  are connected to and supported by first and second spaced support columns  28  and  30 . The first and second support columns  28 ,  30  respectively include upper mounting brackets  28   a  and  30   a  for attaching the support columns to upper frame members in the building structure within which the roll-up curtain assembly  10  is installed. The first and second support columns  28 ,  30  are also provided with respective lower mounting brackets,  28   b  and  30   b  for attaching the support columns to an upward extending edge  16   a  of the building structure&#39;s base, or floor,  16 . The building structure itself within which the roll-up curtain assembly  10  is installed is not shown in the figures for simplicity. 
     Respective upper edges of the upper and lower curtains  12 ,  14  are each provided with a hem. Inserted within the upper hem of the upper curtain  12  is a first rod  18 , while inserted through the upper hem of the lower curtain  14  is a second rod  20 . Each of the first and second rods  18 ,  20  is fixedly coupled to the first and second curtain support columns  28  and  30  by conventional means such as mounting brackets which are described below. The lower edge of the upper curtain  12  is also provided with a hem in which is inserted a third rod  22 . Similarly, an intermediate portion of the lower curtain  14  is provided with a hem into which is inserted a fourth rod  24 . Finally, the lower edge of the lower curtain  14  is provided with a hem into which is inserted a fifth rod  26 . Each of the rods is preferably comprised of a high strength, lightweight material such as aluminum or plastic and extends the full length of the curtain within which it is disposed. In addition each of the rods is preferably in the form of a hollow tube to reduce its weight. In the embodiment shown in  FIGS. 1 and 2 , the lower curtain  14  includes an upper section  14   a  disposed between the second and fourth rods  20 ,  24  and a lower section  14   b  disposed between the fourth rod and the fifth rod  26 . However, this invention is not limited to this configuration, as both curtains may include only a single section, both curtains may include plural sections, or the roll-up curtain assembly may include more than two vertically aligned roll-up curtains in accordance with the principles of the present invention. 
     The ends of each of the upper and lower curtains  12 ,  14  are further connected to a support-drive mechanism  40  which is shown in greater detail in the perspective view of FIG.  3 . Support/drive mechanism  40  includes a support frame  42  comprised of first and second vertical side frame members  42   b  and  42   c  and an upper frame member  42   a  connecting the upper ends of the side frame members. A lower frame member  42   d  connects adjacent lower ends of the first and second side frame members  42   b,    42   c.  Support/drive mechanism  40  further includes third and fourth side frame members  50   a  and  50   b  disposed adjacent to and spaced from the first and second side frame members  42   b  and  42   c,  respectively. The space between the first and third side frame members  42   b,    50   a  forms a first retainer slot  51   a,  while the space between the second and fourth side frame members  42   c  and  50   b  forms a second retainer slot  51   b.  Disposed within the first retainer slot  51  a are respective ends of the third rod  22  and the fourth rod  24  (shown in dotted line form in FIG.  3 ). Inserted through the second retainer slot  51   b  are sixth and seventh rods  36  and  38  also shown in dotted line form in FIG.  3 . The sixth and seventh rods  36 ,  38  are respectively coupled to adjacent upper and lower curtains  32  and  34  which are not shown in  FIG. 3  for simplicity, but are shown in  FIGS. 1 and 2 . Each of the aforementioned rods is freely movable within its associated retainer slot as the upper and lower curtains are displaced upwardly or downwardly within the support frame  42  as described in the following paragraphs. First, second, third and fourth cover panels  44   a,    44   b,    44   c  and  44   d  extend between and are coupled to the first and second side frame members  42   b  and  42   c.  A first upper mounting bracket  46   a  is coupled to respective upper ends of first side frame member  42   b  and third side frame member  58   a.  Similarly, a second upper mounting bracket  46   b  is connected to respective upper ends of second side frame member  42   c  and fourth side frame member  50   b.  The first and second upper mounting brackets  46   a,    46   b  are further coupled to the upper frame member  42   a  of the frame support  42  and facilitate attaching the support/drive mechanism  40  to an upper portion of the building structure within which the roll-up curtain assembly is installed. 
     Attached to adjacent ends of third rod  22  and sixth rod  36  by means of a first drive shaft  54   a  is an upper motor/gearbox combination  52   a.  Similarly, attached to adjacent ends of fourth rod  24  and seventh rod  38  by means of a second drive shaft  54   b  is a lower motor/gearbox combination  52   b.  Rotation of the third rod  22  by the upper motor/gearbox combination  52   a  causes the upper curtain  12  to be either rolled-up unto or unrolled from the third rod in raising or lowering the upper curtain. Similarly, rotation of the fourth rod  24  by means of the lower motor/gearbox combination  52   b  causes the lower curtain  14  to be rolled-up on or unrolled from the fourth rod. Similarly, rotation of the sixth rod  36  by means of the upper motor/gearbox combination  52   a  and rotation of the seventh rod  38  by means of the lower motor/gearbox combination  52   b  causes respective curtains attached to these rods to be either retracted or extended. The upper and lower motor/gearbox combinations  52   a,    52   b  are coupled by means of connecting bar  56  so that the two motor/gearbox combinations and rods connected thereto move in unison either upward in rolling the curtain section up to the retracted position or downward in unrolling the curtain sections from the supporting rods and moving the curtain to the fully extended, or closed, position. 
     Additional details of the roll-up curtain is shown in the partial perspective view of FIG.  4 . As previously described, the upper curtain  12  includes an upper hem  12   a  within which is inserted the first rod  18 . Upper curtain  12  further includes a lower hem  12   b  within which is inserted the third rod  22 . Similarly, lower curtain  14  includes upper, intermediate and lower hems  58   a,    58   b  and  58   c  within which are respectively disposed the second, fourth and fifth rods  20 ,  24  and  26 . A pair of threaded coupling pins  70   a  and  70   b  fixedly attach the third rod  22  to the lower hem  12   b  of the upper curtain  12 . Thus, when the third rod  22  is rotationally displaced, the upper curtain  12  is either rolled up onto or is unrolled from the third rod. Similarly, threaded couplers are used to fixedly attach the fourth rod  24  to the intermediate hem  58   b  of the lower curtain  14  to ensure that when the fourth rod is rotationally displaced, the upper and lower sections  14   a  and  14   b  of the lower curtain  14  are either rolled up onto or unrolled from the fourth rod. Attached to the fifth rod  26  as well as to the lower hem  58   c  of the lower curtain  14  is a protective sleeve  60 . Protective sleeve  60  is attached to the fifth rod  26  and the lower hem  58   c  by means of threaded coupling pins  62   a  and  62   b.  Protective sleeve  60  is preferably comprised of a lightweight, semi-rigid and durable material such as PVC to afford protection for the lower edge of the curtain. Also shown is the manner in which drive shaft  54   b  is securely coupled to an end of the fourth rod  24 . The narrowed end of the drive shaft  54   b  is telescopically inserted in an adjacent end of the fourth rod  24  and the connection between these shafts is maintained by means of threaded coupling pins  68   a  and  68   b.  A similar connection arrangement to an upper drive shaft is provided for attaching the drive shaft to the third rod  22 , but details of this connecting arrangement are not shown in  FIG. 4  for simplicity. 
     Referring to  FIG. 5 , there is shown a side elevation view of additional installation details of a roll-up curtain assembly  80  in accordance with the principles of the present invention. As in the previously described embodiment, roll-up curtain assembly  80  includes an upper curtain  82  and a lower curtain  84 . Upper and lower edges of the upper curtain  82  are provided with respective hems, with a first rod  86  inserted in the upper curtain&#39;s upper hem and a second rod  88  inserted through the upper curtain&#39;s lower hem. Opposed ends of the first rod  86  are inserted in and supported by pipe hanger brackets  118  disposed on adjacent support frames  112 . As described above, the second rod  88  is coupled to a drive mechanism for rotational displacement of the second rod in raising or lowering the upper curtain  82 . 
     The lower curtain  84  is comprised of an upper curtain section  84   a  and a lower curtain section  84   b.  An upper edge of the upper curtain section  84   a  is provided with a hem along the length thereof into which is inserted a third rod  90 . Similarly, the lower end of the lower curtain section  84   b  is provided with a hem into which is inserted a fifth rod  94 . An intermediate portion of the lower curtain  84  is provided with a third hem into which is inserted a fourth rod  92 . Opposed ends of the fourth rod  92  are connected to a drive mechanism for rotationally displacing the fourth rod in either raising or lowering the lower curtain  84  as previously described. Opposed ends of each of the aforementioned rods are disposed within a slot  103  formed between the support frame  112  and a curtain retainer track  102 . Slot  103  maintains all of the aforementioned rods in a generally common vertical alignment during retraction and extension of the curtain as well as when the curtain is in a fixed position. A lower end of the support frame  112  is securely mounted to a concrete base  110  by means of nut and bolt combinations  122   a  and  122   b.  Similarly, a lower end of the curtain retainer track  102  is securely mounted to the concrete base  110  by means of the combination of a lower angle  106  and a mounting screw  108 . Upper ends of the curtain retainer track  102  and support frame  112  are securely attached to a roof structure  96  by means of respective first and second upper mounting brackets  104  and  114 . Roof section  96  includes plural spaced rafters  98   a  and  98   b  as shown in the partial sectional view of FIG.  6  and plural spaced purlins  100   a,    100   b  and  100   c  as shown in FIG.  5 . An optional fixed curtain  124  may be attached to the second purlin  100   b  by means of a mounting bracket  106 . A lower edge of the fixed curtain  124  is provided with a hem for receiving a sixth rod  128  which maintains the fixed curtain in a vertical, stretched configuration as shown in FIG.  5 . 
     Additional details of the manner in which an upper end of the curtain retainer track  102  is securely attached to the roof structure  96  are shown in FIG.  6 . Disposed on opposed sides of the curtain retainer track  102  and attached to the upper edge thereof by conventional means such as a glue or cement composition are the aforementioned upper mounting bracket  104   a  and a second upper mounting bracket  104   b.  Upper mounting brackets, or straps,  104   a,    104   b  are also attached to a pair of side-by-side roof rafters  98   a  and  98   b.  A first mounting screw  130   a  is inserted through upper mounting bracket  104   a  and roof rafter  98   a  for connecting these members, while a second mounting screw  130   b  is inserted through upper mounting bracket  104   b  and roof rafter  98   b  for securely connecting these structural members. Upper portions of the roof rafters  98   a,    98   b,  which each have a generally C-shaped cross section, are connected to roof purlin  100   a  by conventional means such as connecting screws or brackets, which are not shown in the figure for simplicity. 
     Referring to  FIG. 7  there is shown a plan view of another embodiment of a curtain drive mechanism  140  in accordance with the principles of the present invention.  FIGS. 8 and 9  are respectively exploded and assembled perspective views of a double reduction drive mechanism  210  employed in the curtain drive mechanism  140  of FIG.  7 . 
     Curtain drive mechanism  140  includes an upper double reduction drive mechanism  146  and a lower double reduction drive mechanism  170 . Upper double reduction drive mechanism  146  includes a first electric motor  148 , a first gearbox  150 , and first and second paired sprockets, or tooth gears,  152  and  154 . The first paired sprockets  152  are connected to and rotationally drive a first drive rod  156  while the second paired sprockets  154  are coupled to and rotationally displace a second drive rod  158 . The first drive rod  156  is disposed in a first vertical slot formed by a first curtain retainer track  142  and a first support frame (not shown), while the second drive rod  158  is disposed in a second vertical slot formed by a second curtain retainer track  144  and a second support frame (also not shown). The first and second drive rods  156 ,  158  are displaced vertically within a respective slot by operation of the upper and lower double reduction drive mechanisms  146 ,  170  as in the previously described embodiment. An electrical lead  160  is coupled to and provides input power to the first electric motor  148 . 
     The lower double reduction drive mechanism  170  similarly includes a second electric motor  172 , a second gearbox  174 , and third and fourth paired sprockets  176  and  178 . The third paired sprockets  176  are coupled to and rotationally displace a third drive rod  180 , while the fourth paired sprockets  178  are coupled to and rotationally displace a fourth drive rod  182 . An electrical lead  184  is connected to and provides input power to the second electric motor  172 . Each of the third and fourth drive rods  180 ,  182  is inserted in a respective slot formed partially by the first and second curtain retainer tracks  142 ,  144  and are displaced vertically within the slots by operation of the second electric motor  172 . 
     The upper and lower double reduction drive mechanisms  146  and  170  move vertically in unison because they are connected together in the following manner. Attached to the first electric motor  148  by plural connecting pins such as screws is a first mounting plate  162 . Similarly, attached to the second electric motor  172  by plural connecting pins is a second mounting plate  186 . The first mounting plate  162  is connected to respective upper ends of first and second connecting shafts  164  and  166 , while the second mounting plate  186  is coupled to respective upper ends of third and fourth connecting shafts  188  and  190 . Each of the aforementioned shafts is connected to a respective mounting plate by conventional means such as a threaded connecting pins and a mounting bracket which are not shown in the figure for simplicity. Coupling the lower end of the first connecting shaft  164  to the upper end of the third connecting shaft  188  is a first connecting rod  192  while connecting the lower end of the second connecting shaft  166  to the upper end of the fourth connecting shaft  190  is a second connecting rod  194 . Each of the aforementioned first and second connecting rods  192 ,  194  is coupled to a pair of connecting shafts by conventional means such as a set screw or connecting pin (also not shown for simplicity). By thus connecting the upper and lower double reduction drive mechanisms  146  and  170 , the two drive mechanisms move upwardly and downwardly in unison and upper and lower curtains respectively attached to the upper and lower double reduction drive mechanism also move upwardly and downwardly towards the open and closed positions, respectively, in unison. 
     Referring to  FIGS. 8 and 9 , the details of the configuration and operation of each of the double reduction drive mechanisms will now be described. Shown in  FIGS. 8 and 9  respectively in exploded and assembled perspective views is a double reduction drive mechanism  210  as used in one embodiment of the present invention. Double reduction drive mechanism  210  allows larger curtain spans and heights to be accommodated without increasing the input power required to move the curtains between the open and closed positions by increasing the torque applied to the curtain sections. In addition, the double reduction drive mechanism decreases the speed of the curtains being raised or lowered without increasing the speed or power of the drive motor. 
     Double reduction mechanism  210  includes an electric motor  212  connected to a gearbox  214 . Gearbox  214  changes the drive axis from a generally vertical orientation to a horizontal orientation as evidenced by the position of the first and second drive shafts  216   a  and  216   b  extending from an upper portion of the gearbox. The first and second drive shafts  216   a,    216   b  are respectively inserted within an aperture of and connected to first and second drive sprockets  232   a  and  232   b.  The first and second drive sprockets  232   a,    232   b  are coupled to the first and second drive shafts  216   a,    216   b,  respectively, by conventional means such as a shaft keyed or a threaded set screw. Engaging the first and second drive sprockets  232   a  and  232   b  are first and second roller drive chains  230   a  and  230   b,  respectively. The first drive chain  230   a  further engages the teeth of a first driven sprocket  228   a,  while the second drive chain  230   b  engages the teeth of a second driven sprocket  228   b.  Each of the first and second driven sprockets  228   a,    228   b  includes a respective aperture within which is inserted a respective end of a connecting rod  224 . Connecting rod  224  is inserted through aligned first and second brass bushings  222   a  and  222   b  and a spacer rod  220  disposed between the brass bushings. The first and second brass bushings  220   a,    220   b  and the spacer rod  220  are maintained in fixed, spaced position along the length of the connecting rod  224  by means of first and second locking keys  226   a  and  226   b  inserted in respective slots in the connecting rod. Rotation of the drive shafts  216   a  and  216   b  in a first direction causes a corresponding rotation of the drive chains  230   a,    230   b,  the driven sprockets  228   a,    228   b  and the connecting rod  224 , while rotation of the drive shafts in a second, opposed direction results in reverse rotation of the aforementioned components of the double reduction drive mechanism  210  which are connected to the drive shaft. It is in this manner that the rods which are connected to the connecting rod  224  as well as to a curtain section either roll-up or unroll the curtain section. 
     While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the relevant arts that changes and modifications may be made without departing from the invention in its broader aspects. Therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective based on the prior art.

Technology Classification (CPC): 4