Abstract:
The present invention is directed to a modular roll-up partition assembly, such as a rolling protective shutter, implementing an improved mechanism for raising the partition in an emergency by disengaging a motor from a rolling shutter. The mechanism includes a cable that passes through an axial passage in a torsion spring. When the cable is pulled, the coupling mechanism is separated from the motor drive shaft, thereby disengaging the motor drive shaft from the shutter support member and permitting the torsion spring to quickly raise the rolling shutter.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of International Application No. PCT/US99/17809 filed Aug. 3, 1999, which is a continuation-in-part of co-pending U.S. application Ser. No. 09/129,530, filed Aug. 5, 1998 now U.S. Pat. No. 5,975,185. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention is directed to a roll-up partition system assembly which has a protective partition for covering a window or door opening that may be rolled up into a housing when not in use. More particularly, the present invention is directed to a modular assembly implementing an improved emergency opening mechanism for roll-up partition systems. The embodiments disclosed herein illustrated the various aspects of the present invention applied to one particular type of roll-up partition system: rolling protective shutters formed from a plurality of interconnected slats. It will be apparent to those of ordinary skill in the art that the present invention has application in other systems wherein a partition member is coupled to and rolls up onto a support member within a housing, such as roll-up doors, roll-up grills, roll-up gates, fire doors and the like. The application of the present invention to the various types of roll-up partition systems is contemplated by the inventor. 
     One type of roll-up partition system is a rolling protective shutter. Rolling protective shutters are conventional and are used to provide protection against extreme weather conditions and to deter theft, for example. One such rolling protective shutter is disclosed in U.S. Pat. No. 4,345,635 to Solomon. As shown in FIGS. 1 and 2 of that patent, the Solomon shutter is composed of a plurality of elongate slats, each of which has a pair of circular ribs attached to its sides. The slats are interconnected by a plurality of elongate hinges, each of which has a pair of circular apertures in which the circular ribs of the slats are disposed. When the Solomon shutter is unrolled to its protective position, each of the slats in the shutter is disposed vertically with the ends of the slats disposed within guide channels or side tracks on either side of the opening. When not in use, the Solomon shutter may be rolled up into a housing disposed at the upper end of the protective shutter. 
     Another type of rolling protective shutter is disclosed in U.S. Pat. No. 5,575,322 to Miller. As shown, the shutter assembly includes a shutter support member mounted for rotation in a shutter housing. A rolling shutter composed of a plurality of individual slats is coupled to the shutter support member so that the shutter can be rolled up onto the shutter support member. A pair of shutter tracks extend downwardly from either end of the shutter housing. When the shutter is in its unrolled position, the ends of the slats are disposed within the tracks. 
     Roll-up partitions in general, and rolling protective shutters in particular, typically incorporate one or more torsion spring assemblies to assist in rolling and unrolling the shutters manually or by a powered opening device. In one arrangement, the assembly is a self-contained modular unit having a spring shaft surrounded by a coiled torsion spring. One end of the spring shaft includes a spring shaft support that is rotatable about the spring shaft, and a spring plate rigidly fixed to the spring shaft and to the proximate end of the torsion spring to prevent rotation of the end of the torsion spring relative to the spring shaft. The other end of the spring shaft includes a spring drive that is rotatable about the spring shaft and rigidly fixed to the other end of the torsion spring. The assembly is inserted into the shutter support member with one end of the spring shaft rigidly fixed to the shutter housing. The spring shaft support and spring drive engage the interior of and rotate with the shutter support member. When the shutter is unrolled, the torsion spring is wound tighter, thereby providing additional torque to assist in lifting and rolling the shutter onto the shutter support member. During normal operation of the rolling protective shutters, the torsion spring exerts a minimum torque when the shutter is in the rolled position and a maximum torque when the shutter is in the unrolled position. 
     The torsion spring therefore assists in lifting the shutter to an open position, whether motor driven or manually operated. In many municipalities, it is required that a person could easily pull a lever and have any type of security door or gate open (“pop up”) for easy and fast egress in case of an emergency, such as, for example, a fire, inside the building on which the security door or gate is installed. This “pop up” operation must be done mechanically rather than by electrical power, in the event that electrical power is interrupted due to the fire or other emergency in the building. 
     Accordingly, it is necessary to have a system that enables a torsion spring to raise the door or gate by a manual operation. Typically, motor driven security doors or gates use a braking system of some type to maintain the position of the door or gate when the motor is stopped. This braking system must be disengaged when the door or gate needs to be raised. 
     A typical type of overhead door uses a large motor mounted outside of a housing that contains the door or gate when it is rolled up. The motor can be hidden in the ceiling of the building in which the door or gate is installed. Through the use of gears and/or chains, it has been fairly easy to provide a mechanism to disengage the braking system and permit the torsion spring to raise the shutter. However, this type of external motor system is extremely costly, very large, difficult to install, and can be unsightly if it cannot be hidden in a ceiling. 
     One primary alternative to such external motor systems is the use of tubular motors to raise and lower doors and gates. Tubular motors can be encased inside of a roller tube around which the door or gate is wound when the door or gate is opened. As the motor system is always hidden within the roller tube, it is never visible and thereby gives the door or gate a very clean look. The use of a tubular motor also makes installation of the door or gate much simpler. 
     Present designs for rolling doors or gates having tubular motors do not have satisfactory mechanisms for utilizing a torsion spring to raise the door in an emergency. Typically, a cable mechanism is used to manually release a brake inside the tubular motor. Such cable mechanisms do not work well in practice because the required travel of the cable is so small in order to effectively release the brake that the cable mechanisms either simply do not work or are extremely difficult to install properly. Accordingly, presently there are no known commercial manufacturers of tubular motors that offer a system for rolling up a door or gate in an emergency. 
     In other installations, it is desirable to disengage the tubular motor from the partition to allow the partition to be unrolled in an emergency. For example, fire doors are unrolled to cover an opening to prevent the spread of a fire. In the event the fire causes a power outage, it is necessary to disengage the tubular motor and manually unroll the shutter to cover the opening. Accordingly, its is desirable to provide a safety release mechanism that allows a partition to be either rolled up or unrolled in an emergency. 
     In view of the foregoing problems and disadvantages, there is a need for a system that can be used with a tubular motor that enables the use of a torsion spring to open or close a door or gate in case of an emergency. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a roll-up partition assembly, such as a rolling protective shutter, implementing an improved mechanism for opening the partition assembly in an emergency situation. 
     In accordance with a preferred embodiment of the present invention, a mechanism is provided for disengaging a motor from a roller tube of a rolling shutter. The mechanism includes a manually operable actuating member that passes through an axial passage in a torsion spring. The manually operable actuating member is connected to a coupling mechanism. When the manually operable actuating member is pulled, the coupling mechanism is separated from the motor drive shaft, thereby disengaging the roller tube from the motor drive shaft. 
     In an alternative embodiment of the present invention, the coupling mechanism further includes a clutch drive coupled to the drive shaft and a detent holder coupled to the roller tube. A detent is disposed within the detent holder and operatively coupled to the actuating member. When the actuating member is not pulled, the detent couples the detent holder to the clutch drive. When the actuating member is pulled, the detent releases the clutch drive, thereby disengaging the detent holder from the clutch drive. 
     The features and advantages of the invention will be apparent to those of ordinary skill in the art in view of the detailed description of the preferred embodiment, which is made with reference to the drawings, a brief description of which is provided below. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a rolling shutter assembly that can implement the present invention; 
     FIG. 2 is a fragmentary perspective view of a portion of the shutter of the shutter assembly of FIG. 1; 
     FIG. 3 is a schematic top view of a portion of the shutter assembly of FIG. 1, in a configuration for normal, motorized operation; 
     FIG. 4 is a schematic top view of a portion of the shutter assembly of FIG. 1, in a configuration for emergency, manual operation. 
     FIG. 5 is a partial sectional view of a safety release clutch according to the present invention in the engage position; 
     FIG. 6 is a sectional view taken through line  6 — 6  of the safety release clutch of FIG. 5; 
     FIG. 7 is a partial sectional view of the safety release clutch of FIG. 5 in the disengaged position; 
     FIG. 8 is a sectional view taken through line  8 — 8  of the safety release clutch of FIG. 6; and 
     FIG. 9 is a sectional view of the safety release clutch of FIG. 8 after a 45° rotation of the roller tube. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     One type of roll-up partition system, rolling shutter assembly  10 , that may implement the present invention is shown in FIGS. 1-3. Referring to FIG. 1, the shutter assembly  10  has a shutter housing which includes a top wall  12 , a pair of side walls  14 , and a front wall  16 . A partition support member  20  is mounted for rotation within the shutter housing. The support member  20  includes a generally cylindrical central roller tube  22  and a plurality of mounting members  24  fixed to the roller tube  22 . 
     The upper end of a rolling shutter  30  is coupled to the mounting members  24 . Alternatively, however, the mounting members  24  may be omitted and the rolling shutter  30  mounted directly to the roller tube  22 . The shutter  30  is composed of a plurality of individual, elongate slats  32 . One example of a configuration of slats  32  is illustrated in FIG.  2 . The slats  32 , each of which is substantially flat, having two substantially planar side portions, and may be composed of steel, are interconnected by a plurality of hinges  34 , each of which joins together a pair of adjacent slats  32 . 
     Each of the slats  32  includes an upward projection  35  extending longitudinally along the upper edge of the slat  32  and having a rearwardly and downwardly extending hook  36  at the top. Each of the slats  32  further includes a downward facing U-shaped recess  37  extending longitudinally along the lower edge of the slat  32  and having a forward horizontal projection  38  formed on the rear edge of the recess  37 . The hook  36  of a lower slat  32  and the recess  37  and projection  38  of an upper slat  32  interlock to form each hinge  34 . 
     Instead of being integrally formed with the shutter slats  32 , the hooks  36  and U-shaped recesses  37  described above could be separate components connected thereto, such as by bolting or riveting. Instead of hooks and recesses, other locking members having different structures could be used to form the hinges. Other configurations of slats  32  and interconnecting hinges  34 , such as the configuration of the Solomon shutters, are well known in the art and are contemplated by the inventor as having use with the present invention. 
     Referring back to FIG. 1, the ends of the slats  32  are disposed within a pair of shutter tracks  40 . When mounted to protect a window or other opening, the shutter tracks  40  of the shutter assembly  10  are positioned on either side of the opening and the shutter housing is positioned over the top of the opening. Alternatively, in some applications, the side tracks  40  and shutter housing are positioned within the opening. 
     The shutter assembly  10  includes a tubular electric motor  42  (shown schematically in FIGS. 3 and 4) disposed within the roller tube  22 . When the shutter  30  is not in use, it is rolled up on the roller tube  22  via the motor  42  so that it is at least partially enclosed by the shutter housing. 
     Now referring to FIGS. 3 and 4, the motor  42  is directly coupled to the roller tube  22 , on which the shutter rolls up, by means of a motor drive coupling  44  driven by a motor shaft  46  extending from the motor  42 . The motor drive coupling includes a splined socket portion  48  that mates with a splined end portion  50  of an axially movable drive shaft  52 . The splined end portion  50  also mates with a splined drive plate  54  that is fixedly secured to the roller tube  22  for rotation therewith. The axially movable drive shaft  52  passes through a first spacer plate  56  and a second spacer plate  58 . A compression spring  60  wrapped around the axially movable drive shaft  52  is disposed between the first spacer plate  56  and a compression spring plate  62  that is fixed to the axially movable drive shaft  52 . The compression spring  60  tends to press the axially movable drive shaft  52  toward the left as shown in FIG. 3, and thus tends to press the splined end portion  50  of the movable drive shaft  52  into engagement with the splined socket portion  48  of the motor drive coupling  44 . 
     As previously discussed, roll-up partition assemblies incorporate torsion springs to assist in lifting and rolling the shutters. Referring to the right hand portion of FIGS. 3 and 4, the shutter assembly  10  includes a torsion spring assembly  64  that facilitates ease of movement of the shutter  30  from the unrolled position to the rolled position. The torsion spring assembly  64  includes a hollow spring shaft  66  surrounded by a coiled torsion spring  68  disposed within the roller tube  22 . The hollow spring shaft  66  is anchored to the side wall  14  on the right hand side of the rolling shutter assembly  10 . 
     A torsion spring plate  70  is rigidly mounted to the hollow spring shaft  66 . The outer diameter of the torsion spring plate  70  is small enough to allow the roller tube  22  to rotate relative to the hollow spring shaft  66  without engaging the outer surface of the torsion spring plate  70 . The torsion spring plate  70  is rigidly connected to a first end  72  of the coiled torsion spring  68  to prevent rotation of the first end  72  of the coiled torsion spring  68  relative to the hollow spring shaft  66 . 
     The counterbalancing mechanism further includes a spring drive  74  rotatably mounted to the hollow spring shaft  66  adjacent a second end  76  of the coiled torsion spring  68  opposite the first end  72  thereof. The spring drive  74  is rigidly attached to the roller tube  22  for rotation therewith. The second end  76  of the coiled torsion spring  68  is coupled to the spring drive  74  and rotates with the roller tube  22  relative to the hollow spring shaft  66 . When the rolling shutter  30  is unrolled, the coiled torsion spring  68  is wound tighter as the second end  76  connected to the spring drive  74  rotates relative to the first end  72  connected to the torsion spring plate  70 , thereby providing additional torque to assist in lifting and rolling the shutter  30  onto the roller tube  22 . 
     A manually operable actuating member  78  passes through the hollow spring shaft  66  and is connected to the axially movable drive shaft  52 . A bearing  80  is disposed between the manually operable actuating member  78  and the axially movable drive shaft  52 , to prevent twisting of the manually operable actuating member  78  when the roller tube  22  and the axially movable drive shaft  52  are rotated to raise or lower the shutter  30 . The manually operable actuating member  78  can be in the form of a flexible steel cable or a rigid metal rod. When the manually operable actuating member  78  is pulled, the compression spring  60  is compressed and the axially movable drive shaft  52  is moved toward the right, as seen in FIG. 4, disengaging the axially movable drive shaft  52  from the splined socket portion  48 . Once disengaged from the splined socket portion  48 , the axially movable drive shaft  52  is disconnected from the motor  42 , permitting the torsion spring assembly  64  to raise the rolling shutter  30  without having to overcome the torque required to turn the motor  42 . The manually operable actuating member  78  may then be released after the shutter  30  has been raised using the torsion spring assembly  64 . 
     Once the manually operable actuating member  78  is released, the compression spring  60  presses the axially movable drive shaft  52  toward the left, as seen in FIG. 3, re-engaging the axially movable drive shaft  52  to the splined socket portion  48 . The rolling shutter assembly  10 , is therefore ready to be operated using the motor  42 . 
     In installations for larger rolling shutters or doors, larger torsion springs are used to counterbalance the weight of the shutter or door. Consequently, the torsion springs exert greater torque on the roller tube when the curtain is unrolled. The additional torque results in greater friction between splined socket portion  48  and splined end portion  50  as described above, thereby requiring more effort to pull the portions  48 ,  50  apart to release the roller tube  22  from the motor  42 . 
     FIGS. 5-9 illustrate an alternative embodiment of a mechanism for disengaging the motor  42  from roller tube  22 . Referring to FIG. 5, a safety release clutch  100  replaces the pop-up safety device of FIGS. 3 and 4. The safety release clutch  100  is disposed within the roller tube  22  between the motor and the hollow spring shaft (not shown). The clutch  100  includes a clutch drive  102  connected to the motor shaft  46  for rotation therewith. The clutch drive  102  is secured at the shaft end  103  to the motor shaft  46  by a nut  104  to prevent axial movement of the clutch drive  102  relative to the motor shaft  46 . The clutch drive  102  has an axial bore  106  in the clutch end  108  opposite the motor shaft  46 , with four notches or recesses  110  spaced about the inner wall of the axial bore  106 . 
     The safety release clutch  100  further includes a ball holder  112  axially aligned with the clutch drive  102 . The ball holder  112  has a body  114  and a circular tip  116 . The tip  116  is dimensioned to be inserted into the axial bore  106  of the clutch drive  102  until a shoulder  118  between the body  114  and tip  116  abuts the clutch end  108 . The tip  116  is slightly smaller than the axial bore  106  of the clutch drive  102  to allow rotation of the ball holder  112  relative to the clutch drive  102 . 
     The ball holder  112  has an axial throughbore  120  having a narrow portion  122  proximate the clutch drive  102  and an intermediate wide portion  124  opposite the clutch drive  102  joined by a tapered portion  126 . The ball holder  112  also has four radial bores  128  spaced about the central axis of the throughbore  120  that connect the exterior of the tip  116  and the tapered portion  126  of the throughbore  120 . The radial bores  128  form races for ball bearings  130  that couple the ball holder  112  to the clutch drive  102  in a manner described more thoroughly below. 
     A plunger  132  is slidably disposed within the axial throughbore  120  of the ball holder  110 . The plunger  132  includes a tip  134 , a body  136  and a tapered portion  138  that correspond to the narrow portion  122 , wide portion  124  and tapered portion  126 , respectively, of the throughbore  120 . The plunger  132  further includes an axial shaft  140  extending outwardly from the plunger body  136  in the direction opposite the clutch drive  102  and beyond the end of the body  114  of the ball holder  112 . The plunger shaft  140  has a smaller diameter than the throughbore  120  and the plunger body  136 . The shaft  140  is surrounded by a bushing  144  and a coil spring  144  that are disposed within the throughbore  120  and between the plunger body  136  and the end of the ball holder  114 . The bearing  142  and spring  144  are held within the throughbore  120  by a drive plate  146  that abuts the end of the ball holder body  114  and is held against the body  114  by fasteners such as screws  148 . The plunger shaft  140  extends through an axial opening  150  in the drive plate  146  and is slidable therein. The end of the plunger shaft  140  is connected to the actuating member  78  by a bearing  80  in the same way described for the drive shaft  52  of FIGS. 3 and 4. 
     Clutch drive plate  152  and ball holder drive plate  154  provide additional support for the safety release clutch  100  within the roller tube  22 . The clutch drive plate  152  is disposed proximate the shaft end of the clutch drive  102  and has an opening  156  through the shaft end  103  of the clutch drive  102  is inserted. The opening  156  and the shaft end  103  are dimensioned so that the shaft end  103  may rotate relative to the clutch drive plate  152 . The ball holder drive plate  154  is disposed about the body  114  of the ball holder  112  and is coupled to the body  114  so that the ball holder  112  and drive plate  154  rotate together. The plates  146 ,  152 ,  154  are coupled to the roller tube  22  for rotation therewith. Consequently, when the shutter is rolled or unrolled, the plates  146 ,  152 ,  154  and ball holder  112  rotate with the roller tube  22 . 
     The plates  146 ,  152 ,  154  and, consequently, the safety release clutch  100  are held together by fasteners, such as screws  158 . The screws  158  prevent the plates  146 ,  152  from moving axially in opposite directions, thereby keeping the plunger  132  and ball holder tip  116  disposed within the axial bore  100  of the clutch drive  102 . Moreover, the plate  152  engages a shoulder  160  between the shaft end  103  and clutch end  108  of the clutch drive  102  to further prevent the ball holder  112  and plunger  132  from separating from the drive clutch  102 . Although the plates  146 ,  152  hold the clutch  100  together, the screws  158  are not clamped so tight that the friction between the shoulder  118  and clutch end  108 , and the shoulder  160  and drive plate  152  prevents the ball holder  112  and drive plate  152  from rotating relative to the motor shaft  46  and drive clutch  102  when the safety release clutch  100  is disengaged. 
     FIGS. 5 and 6 illustrate the safety release clutch  100  in the engaged position. The spring  144  exerts a force against the drive plate  146  and biases the plunger body  136  into mating relationship with the throughbore  120  of the ball holder  112 . When the races  128  are aligned with the recesses  110  in the axial bore  106  (FIG.  6 ), the ball bearings  130  are forced into the recesses  110  by the tapered portion of the plunger  132 , and the plunger  132  mates with the throughbore  120 . The ball bearings  130  engage the recesses  110 , resulting in an interference fit between the clutch drive  102  and the ball holder  112  as both elements engage the ball bearings  130 . In this position, the motor shaft  46 , clutch drive  102 , ball holder  112  and roller tube  22  rotate together when the motor drives the motor shaft  46 . The spring  144  is designed to exert enough force to prevent axial movement of the plunger  132  as the ball bearings  130  exert a force on the tapered portion  138  as the motor raises and lowers the shutter curtain. 
     The safety release clutch  100  disengages the roller tube  22  from the motor shaft  46  when the actuating member  78  is pulled. FIGS. 7-9 show the clutch  100  in the disengaged position. As previously discussed, the plunger shaft  140  is coupled to the actuating member  78 . When the actuating member  78  is pulled, the plunger  132  moves axially against the force of the spring  144  until the plunger body  136  engages the bushing  142 . In this position, the tapered portion  138  of the plunger  132  has moved past the ball bearings  130  and is replaced by the tip portion  134 . The distance between outer surface of tip portion  134  and the outer surface of the ball holder tip  116  is greater than the diameter of the ball bearings  130 . As a result, the ball bearings  130  are free to move within the races  128  and are not forced to stay in the recesses  110  of the axial bore  106 . When the roller tube  22  and the components of the safety release clutch  100  attached thereto rotate with respect to the motor shaft  46  and drive clutch  102 , such as in FIG. 9 where the roller tube  22 , plate  152  and ball holder  112  have rotated  450  with respect to the clutch drive  102 , the ball bearings  130  are free to retreat into the races  128  as the races  128  pass the recesses  110 . When the actuating member  78  is released, the spring  144  biases the plunger  132  toward the drive clutch  102  and the tapered portion  138  forces the ball bearings  130  outwardly through the races  128 . When the recesses  110  of the axial bore  106  align with the races  128 , the ball bearings  130  are forced into the recesses  110  to couple the ball holder  112  to the clutch drive  102 , thereby reengaging the clutch  100 . 
     The embodiments disclosed herein illustrate the various aspects of the present invention applied to a rolling protective shutter. It will be apparent to those skilled in the art that the present invention may be applied to other systems wherein a partition member is coupled to a support member and rolled up into a housing. Such partition systems include roll-up doors, roll-up grills, roll-up gates and the like. The application of the present invention to the various types of roll-up partition systems is contemplated by the inventor. 
     Other modifications and alternative embodiments of the invention will be apparent to those skilled in the art in view of the foregoing description. This description is to be construed as illustrative only, and is for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of the structure and method may be varied substantially without departing from the spirit of the invention, and the exclusive use of all modifications which come within the scope of the appended claims is reserved.