Patent Publication Number: US-2015075336-A1

Title: Power Tool To Spring Torsioner Converter

Description:
REFERENCES CITED 
       
     
       
         
           
               
               
               
             
               
                   
               
             
            
               
                 3921761 (w/o motor) 
                 Nov. 25, 1975 
                 Votroubek, Leland C. 
               
               
                   
                   
                 Nelsen, Duane H. 
               
               
                 3979977 (w/, w/o motor ) 
                 Sep. 14, 1976 
                 Dorma, Edward 
               
               
                 4817927 (mounting cones) 
                 Apr. 4, 1989 
                 Martin, David O. 
               
               
                 6148700 (window sashes) 
                 Nov. 21, 2000 
                 Upholz, Michael R. 
               
               
                 6615897 (w/o motor) 
                 Sep. 9, 2003 
                 Dorma, Edward 
               
               
                 6644378 (perm. assembly) 
                 Nov. 11, 2003 
                 Mitchell, Albert W. 
               
               
                 7296607 (perm. assembly) 
                 Nov. 20, 2007 
                 Krupke, LeRoy G. 
               
               
                   
                   
                 Suchici, Marius C. 
               
               
                 7784521 (perm. assembly) 
                 Aug. 31, 2010 
                 Mullet, Willis J. 
               
               
                   
                   
                 Green, Kelly Ray 
               
               
                   
                   
                 Bennett, Thomas B., III 
               
               
                   
               
            
           
         
       
     
     FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     PARTIES TO A JOINT RESEARCH AGREEMENT 
     Not Applicable 
     SEQUENCE LISTING ON A CD 
     Not Applicable 
     BACKGROUND OF INVENTION 
     (1) Field of the Invention 
     Implements (or devices) for applying tension (in this case, torque) to wire or strip. 
     (2) Description of Related Art 
     Power tools, using air or electric motors, are commonly used to rapidly turn nuts, bolts, and screws. However, these tools as currently marketed are not designed to apply twisting (torsion) forces to the springs of a counterbalancing mechanism of a door, such as an overhead garage door system. 
     Most of these door mechanisms utilize long coil springs that are placed under a rotational or torsion force to apply a lifting force to the door. The springs are concentrically positioned about a rotatable shaft mounted on fixed supports. The shaft carries drums accommodating cables, and these cables are attached to the bottom panel of the door so that when the drums are rotated, a lifting force will be applied to the door. The lifting force is transmitted from the torsion springs to the drums by the shaft. The springs must be anchored on one end, and the free end connected to a winding cone on the shaft, and the winding cone is then rotated to “load” the springs (place the springs under torsion force). When the torsion force is “loaded”, the winding cone is then connected to the shaft by a mechanical means, and the system is ready. 
     Previously, long steel rods have been used to insert into open bores in the winding cone to rotate the winding cone and “load” the spring. The amount of force that can be applied to the spring is limited by the strength of the person using the rods, since rotating the winding cone in this manner is a manual operation. The procedure requires a considerable amount of time and can be dangerous as the spring becomes loaded with considerable force. 
     There have been other designs patented to introduce temporary mechanical power to “load” these door springs (see references U.S. Pat. Nos. 3,192,761, 3,979,977 &amp; 6,615,897 cited). These require some setup work over the shaft or at the winding cone (for each spring) before they can begin to “load” the spring. The others referenced are for permanently installed mechanisms, increasing both the installation and subsequent repair costs. This invention is safer to use than a manual procedure, and eliminates the setup times of the other inventions. This invention also utilizes a simpler design with fewer moving parts to wear out, and eliminates the increased costs associated with the permanent mechanisms. 
     SUMMARY OF THE INVENTION 
     This device is related to an apparatus for applying rotational force to an object, as a fastener, a fastener assembly, or the winding cone connected to a spring of a door counterbalancing mechanism. More particularly, the device converts a power tool to apply rotational force to a torsion coil spring of a door counterbalancing mechanism. The device has a casing with a slot to accommodate the shaft of the counterbalancing mechanism. The casing is connected to a power tool that can be held during rotation of the driven member. The power tool can also be engaged by a fixed support to prevent rotation of the casing during winding of the spring of the door counterbalancing mechanism. The rotatable driven member is housed in the casing. The driven member has a slot to accommodate the shaft. A power transmitting means housed in the casing is operable to continuously drive the driven member. A motor, such as an electric motor, is used to apply power to the power transmitting means. The driven member is connected to the winding cone with a novel cast coupling structure. One form of the novel cast coupling structure has an attached hook aligned to engage an open bore in the winding cone. An alternate form of the cast coupler has the hook incorporated in the casting. Other forms of engagement can be incorporated by modifying the coupler. 
     An object of the invention is to provide a power tool, usable with no set up required, to apply torsion forces to the spring of a door counterbalancing mechanism which is simple, safe and convenient to use and requires only one person. A further object of the invention is to provide a power tool for applying torsion forces to the spring of a door counterbalancing mechanism that is operable, with a minimum of time and effort, to apply the torsion forces to the spring sufficient to counterbalance the door. Another object of the invention is to provide a power tool that includes a motor that is compact in construction, relatively lightweight and efficient in use to apply torsion forces to the spring of a door counterbalancing mechanism. Yet another object of the invention is to provide a reliable power tool with a drive member having a slot to accommodate an object, as a shaft, so that the driven member can be concentrically located with the shaft whereby on rotation of the driven member rotational forces can be applied to an object mounted on the shaft. These and other objects and advantages of the invention are embodied in the following description of the preferred embodiments of the invention. 
    
    
     
       IN THE DRAWINGS 
         FIG. 1  shows an elevation view of a sectional overhead door in the closed position; 
         FIG. 2  shows a fragmentary elevation view of the spring area of the counterbalancing mechanism; 
         FIG. 3  shows a right elevation view of the body of the invention, without the coupler of sheet  3 ; 
         FIG. 4  shows a plan view of the top of the coupler; 
         FIG. 5  shows an elevation view of the coupler; 
         FIG. 6  shows a plan view of the bottom of the coupler; 
     
    
    
     (i) DESCRIPTION OF PREFERRED EMBODIMENTS: 
     Referring to the drawings,  FIG. 1  on Sheet  1  shows a conventional overhead door  100  in the closed position mounted against a structural wall. Overhead doors are usually made of metal, plastic or wood panels and have considerable weight.  FIG. 2  on Sheet  1  shows a counterbalance mechanism  200  which is used to facilitate the safe and easy opening and closing of door  100 . 
     Counterbalance mechanism  200  is located above the top of door  100  and has a generally transverse shaft  207 . Transverse shaft  207  can be either hollow tube or solid bar, but the choice is determined by the weight to be lifted, and the outside diameter is the same for both. Opposite end portions of shaft  207  are supported in rotatable bearings  214  and  215 . The center portion of shaft  207  is supported in a rotatable bearing  213 . A plurality of fasteners (not shown) connect the supports  214 ,  215  &amp;  213  to the structural wall adjacent to the top of door  100 . In some installations, the shaft  207  may be supported in bearings on the remote ends of the tracks  101  and  102  near the door opening motor. Adjacent to bearing  214  is drum  216  which is mechanically connected to shaft  207  by a set screw (similar to  212 ), and carries cable  208  to an attachment with a suitable fastener (not shown) to the bottom of door  100 . Adjacent to bearing  215  is drum  217  which is mechanically connected to shaft  207  by a set screw (similar to  212 ), and carries cable  209  to an attachment with a suitable fastener (not shown) to the bottom of door  100 . 
     Shaft  207  is subjected to rotational or turning forces by a pair of coil or helical springs  203  and  204 . The static end of spring  203  is connected by anchor cone  201  to support bearing  213 , and the opposite end is connected to winding cone  205 . Cone  205  is mechanically connected to shaft  207  by a set screw  212 . Set screw  212  can be released so that cone  205  can be rotated relative to shaft  207  to twist spring  203 . The static end of spring  204  is connected by anchor cone  202  to support bearing  213 , and the opposite end is connected to winding cone  206 . Cone  206  is mechanically connected to shaft  207  by a set screw  212 . Set screw  212  can be released so that cone  206  can be rotated relative to shaft  207  to twist spring  204 . In some installations, a single heavy duty (larger wire gauge) spring is used to apply the counterbalancing rotational force to shaft  207 , using similar mounting and connection scenarios as described above. 
     When door  100  moves from the open to the closed position, springs  203  and  204  are energized by the twisting action of shaft  207 . The shaft  207  rotates as door  100  moves to its closed position, inducing sufficient inertial energy (torque) into springs  203  and  204  to counterbalance the majority of the weight of door  100 . Springs  203  and  204  then have sufficient inertial energy (torque) so that door  100  can be opened with little effort. When door  100  is in the open position, springs  203  and  204  must retain a small amount of inertial energy (torque) to keep cables  208  and  209  taut, preventing the accidental closing of door  100 . During door installation, winding cones  205  and  206  must be rotated and then connected to shaft  207  when door  100  is in the closed position, in order to set the initial amount of torque in springs  203  and  204  required for proper operation of door  100 . 
     Prior to the present invention, the winding cones  205  and  206  were provided with a plurality of radial open bores  210  (see reference U.S. Pat. No. 4,817,927 cited) for the purpose of receiving long removable rods (not shown). These long rods were used to selectively hold and rotate the cones ¼ turn per rod insertion, thereby applying torque to the springs. When sufficient torque is applied to the springs, the winding cones  205  and  206  are connected to shaft  207 . The rods used to rotate the winding cones  205  and  206  are then released and removed from the cones so that the torque of springs  203  and  204  is transmitted via the winding cones  205  and  206  to shaft  207 . The power apparatus of the invention indicated on Sheets  2  &amp;  3  is used to place the springs  203  and  204  under tension by turning the winding cones  205  and  206 . Once the winding cones  205  and  206  are turned to the required torque, they are connected to shaft  207 . 
     Referring to  FIG. 3  on Sheet  2 , the converter  300  consists of a cast metal housing with four distinct sections; the reduction gear section  1 , the worm gear section  2 , the driven gear section  3  and the handle  6 . The reversible motor of power source  7  is connected by electrical cable to a standard electrical outlet. An on-off trigger switch and a reversing switch are used to control the power to the motor. The converter  300  attaches to an existing power tool body  7  (motor included but not shown). 
     Power is transmitted from the motor, through the reduction gearing (not shown), to an output shaft carrying a worm gear (not shown). The worm gear (not shown) drives the rotatable driven gear  5  mounted in section  3  of the housing. The driven gear  5  rests against a bearing shoulder of the same size as snap ring  4 , and is secured in section  3  of the housing by snap ring  4 . Driven gear  5  has a concentric semi-octagonal hole  13  to accommodate the novel coupler  400  on Sheet  3 , and a radial slot  12  of a size required to accommodate shaft  207 . The opening in the cast housing  300  is larger than slot  12  to allow for motor-spin and driven gear  5  movement after electrical power cut-off. 
     Referring to  FIGS. 4-6  on Sheet  3 , these show three views of novel coupler  400  for connecting to and rotating the winding cones  205  and  206 . The cap  9  of novel coupler  400  is chrome steel with four holes  11  provided for screws (not shown) to attach cap  9  to body  8 . A stainless hook  10  is welded to cap  9  and engages an open bore  210  on winding cone  205  or  206 , winding either spring  203  or  204  to the required torque. Novel coupler  400  is inserted into hole  13  in driven gear  5  from the side toward the spring to be wound. An alternative method of winding springs  203  or  204  is to omit cap  9  and engage tabs  211  on winding cones  205  or  206  into slots  15  in body  8 . 
     The body  8  of the novel coupler  400  is made of cast metal, and has three ridges  16  which are uniquely shaped, so that when slot  14  is aligned with slot  12  in the driven gear, they will fit into corresponding points of the octagonal hole  13  of driven gear  5 . This positions novel coupler  400  concentrically with driven gear  5 , and with winding cones  205  or  206  and shaft  207 , perfectly aligning all parts for winding springs  203  or  204  to the required amount of torque. 
     This converter  300  can also be used as a portable pipe threader to cut threads onto pipe ends by replacing coupler  400  with the appropriate size pipe die and cutting blades. 
     While there have been shown and described preferred embodiments of the invention, it is understood that changes in materials, size of the components, power transmission structures, coupling structures and other components can be made by those skilled in the art without departing from the invention.