Abstract:
A non friction motor driven telescoping row based seating system having a direct drive motor apparatus for engaging a drum which winds and unwinds interconnected drive carriages on said drum to provide telescoping and retraction movement to the seating system.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a power system for a telescoping bleacher seating system and more particularly, to an improvement in the method for extending and retracting bleacher seats. 
     Telescoping seating systems are well-known in the art, and generally include a plurality of benches, each bench having a seating frame or understructure including columns or posts extending vertically from a base on wheels, to the height of a given bench. 
     Telescoping seating systems can be bench seating systems or seating systems which have individual seat supported on benches, such as for stadium or convention center seating. 
     Non friction drive systems do not frictionally engage the floor, but instead include an extendable chain that extends from a power drive mechanism positioned at the rear of the telescopic seating structure. Further the extendable chains if not properly adjusted can cause the telescopic seating to extend non-linearly. This condition can cause the extendable chair and/or the telescopic seating to skew, resulting in alignment difficulties. Under extreme conditions, non-linear extension may cause the chain to deform, particularly at the outermost end of the chain where the chains are the weakest and experience the greatest stress. Known extendable chains and the mechanisms for driving them also tend to be quite complex and sensitive to wear, such that they require constant maintenance and adjustment to keep them in proper working condition. A need has long existed for a system, which requires less maintenance in the field, and less sensitivity to stress. 
     Power systems are used to move the telescoping benches between the use and storage positions. One such power system is disclosed in U.S. Pat. No. 4,285,172. Despite the convenience and labor savings provided by such power systems, a need has existed for safer power systems, which do not require the use of chains, or sprockets, which can engage fingers and break or rip human flesh. 
     A principal object of the present invention is to provide a non friction power system for bleacher type seating which is expandable and collapsible for storage, which utilizes a direct drive system without the need for chains or sprockets. 
     Another object of the present invention is to provide a non friction stadium seating system which installers can simply and easily place in the field without the need for additional and expensive welding of the units. 
     Still a further object of the present invention is to provide a motor which is of a lower horse power but of a higher torque and is capable of moving at least 20 or even more rows of bleachers but using less energy than in the past. 
     Other features and advantages of the present invention will be apparent from the following drawings wherein identical reference numerals will be used to refer to like parts of the various views. 
     SUMMARY 
     The present invention relates to a telescopic seating system, comprising seats disposed on a frame, which is operably connected to a motor system,. Further, it includes a plurality of interconnected drive carriages adapted for connection to a telescopic seating system to extend and retract the telescopic seating system, drive carriages being configured to selectively mateably wind onto and off from the drum as the drum is rotated. The motor system comprises a drum, a drum frame, at least two drum shafts rotatably engaged to said drum. The power mechanism is attached to the drum frame further having a motor attached to a motor frame, at least two motor shafts extending from each side of said motor, and a drive shaft connected to the motor shafts. The drip means enables the motor to rotate the drum and thereby extend and retract drive carriages which move the seats, and wherein the motor and drum engage the drive carriages so that the drive carriage move in substantially continuously tangentially alignment as the drive carriages are selectively retracted and extended by the drum. 
    
    
     THE DRAWINGS 
     FIG. 1 is a side view of the bleacher seats in an extended position; 
     FIG. 2 is a top view of the novel direct drive power system using a plurality of drums; 
     FIG. 3 is a front view of a drum; 
     FIG. 4 is a top view of a drum; 
     FIG. 5 is a top view of a power system; 
     FIG. 6 is a front view of a drum; 
     FIG. 7 is a side view of a drum; and 
     FIG. 8 is a side view of a motor. 
    
    
     These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims and appended drawings. 
     DETAILED DESCRIPTION 
     FIG. 1 depicts the unique telescoping seating system  100  which is the combination of the non friction direct drive power system and an embodiment of the bench seating components having seven components,  106 ,  106 A,  106 B,  106 C,  106 D,  106 E and  106 F. 
     Sections  106 ,  106 A,  106 B,  106 C,  106 D,  106 E and  106 F include complementary components that are folded into each other, as are generally known in the art, thus only one section is described herein. A seating frame  24  is mounted by means of a stanchion bracket  26  to the deck portion  28  of a bench. Seat  28  is attached to a cantilever arm  26 , which attaches to column  30 . Column  30  attaches to foot  34 . Decking material  32  is detachably engaged to the cantilever arm  26 . A set or a bench can be attached to the decking material  32 . Foot  34  has wheels  36  for carrying the load of the bleaches directly to the floor  2 . 
     Telescoping seating  110  includes a plurality of sections operably interconnected for telescoping collapsible movement. In FIG. 1, 7 sections are shown, however it is contemplated that many sections can be sued with the non friction direct drive system. Further other seating systems that re known in the art can be used with the direct drive power system. Thus the seating disclosed herein is for illustrative purposes only and is not intended to be unnecessarily limiting. 
     FIG. 2 depicts a direct drive power system  102  embodying the present invention is provided for in FIGS. 2 and 4 for extending and retracting telescopic or folding seating, such as benches or individual chairs deployed on benches. 
     Returning to FIG. 2, the direct drive power system  102  includes a motor  104 , operably mounted on a motor frame  103  which is attached to the seating components  106 . Drum  116  is connected via drive shaft  123  to motor  104  via shaft coupler  120  and motor coupler  118  and coupler  122  provides the connection. Drum  117  is connected via drive shaft  125  to motor  104 . 
     At least four shaft couplers are contemplated for use within the scope of the present invention, motor coupler  118 , shaft coupler  120 , drum shaft coupler  122 , and shaft coupler  124 . Additional shaft couplers could be used, depending on the overall length of the telescoping seating to be used 
     FIG. 3 shows that motor  104  has first motor shaft  108  and second motor shaft  110  operably connected to motor  104 . First motor shaft  108  operable connects to drive shaft  123  via motor coupler  118 . Second motor shaft  110  connects to the drive shaft  125  via coupler  120 . Motor  104  is supported by motor flanges  107  mounted on motor frame  103 . 
     Typical stock couplings available from Martin can be used in this invention. Most preferably, couplings which are prebored,  1  and ¼ inch couplings having a keyway cut into the coupling, such as the Martin model 5018 are usable herein. Other types of couplings could be used, such as model L090-500 available from Lovejoy. 
     FIG. 4 shows that drum shaft  112  is operatively connected to a first drum  116 . Drum shaft  112  connects to coupler  122 , which connects to drive shaft  123 . All parts are supported on a drum frame  105 . 
     FIG. 5 shows first motor shaft  108  connected to motor coupler  118 . Motor coupler  118  connects to drive shaft  123 . Motor shaft  110  is coupled via motor coupler  120  to connect with drive shaft  125 . Motor frame  103  supports motor  104  with motor flange  107 . 
     FIG. 6 shows drum  117  having drum shaft  114  connected to coupler  124 , which ties to drive shaft  125 . Drum  117  rests on drum frame  200 . 
     In FIG. 7, drum  117  is a six-sided structure defining a plurality of flat sides around its perimeter for mateably receiving a plurality of drive carriages  38  with casters  37  attached to the carriages. Drum  117  is narrow enough to fit in the back row of the bleacher seating system. Drum  117  has a drum shroud  46  to protect humans from the safety hazards associated with operating this machinery. 
     In the most preferred embodiment, drum  117  has six sides,  150 ,  152 ,  154 ,  156 ,  158  and  160  arranged in a spiral type arrangement that are particularly configured to receive drive carriages  38 . It is noted that a drum with fewer than six could work within the scope of the present invention. However, a six sided structure is considered the preferred embodiment. 
     Preferably, each of these sides is arranged 60 degrees apart from each other. Six is considered the optimal number of sides for the drum so that the carriages are pushed out across the surface rather than down into the floor. The six-sided structure reduces the torque on the carriages to move them. 
     It is noted that an alternative number of sides can be used if desired. The 6 sides define and increasing radial distance relative to the axis defined by the drum shafts, such that the last end of the sixth&#39;s side is spaced radially from the first end of the first side by a set radial instance. Radial distances are equal to the thickness of the drive carriages. Each of the sides of a drum,  150 ,  152 ,  154 ,  156 ,  158  and  160  has an equal length. 
     Each carriage has a push plate or a “drum engagement plate  302 ” for engaging the drum. These drum engagement plates are positioned at a force-absorbing angle so that the drum can engage the carriages to pull the drive carriages around the drum, thereby retracting the bench system. 
     The drive carriages are interconnected using hinges  300  forming a continuous series of interlinked drive carriages. The hinges  300 , typically are butt hinges are welded to the drive carriages, although detachable hinging means could be used to connect the drive carriages rather than a welded connecting means. The drive carriages further have an extension welded to them. The drum engagement plate generally forms a right angle to the butt hinge. 
     Casters  37  are affixed to drive carriages  38 . Casters  37  on the bottom of the drive carriages are preferably preassembled casters with wheel size to be a minimum of ⅞″ wide×2″ tall. Casters  37  preferably, contain flanges, which are welded to the bottom of the drive carriages. 
     The present invention utilizes interconnected drive carriages fabricated of C channel 4×12×¼″. Each drive carriage has a 12″ link and a 4×4×{fraction (3/16)}″ butt hinge and 2 ½×2 ½×¼″ angle stop welded to a 2 ½×{fraction (3/16)}″ flat strip welded on front of angle stop to relieve stress from hinges. It is this angle stop with flat strip, which comprises each of the extensions noted above. 
     Returning again to FIG. 1, the system is shown in the extended position for use in a gym. The telescoping benches are shown in stepped or tiered relationship with each other. When the bench system is retracted for storage, the benches are generally vertically aligned with a lower bench nested beneath a higher bench. It is contemplated to be within the scope of the present invention, that this concept be applied to telescoping seating systems which have individual chairs mounted on the benches of the seating. 
     Referring now to FIG. 1, drum  116  is supported on drum pillow block  44  In FIG. 4, pillow blocks  44  and  45  are shown. A drum shroud  46  provides a protective cover so that as drive carriages  38  are rolled up onto the drum  116  so the casters  37  do not provide a safety hazard to people near the bleacher unit. 
     Drums are preferably six sided units consisting of 3×3×¼″ steel angle mounted to a 1 and ¼ inch OD center shaft. Brackets used for mounting angles to the shaft are to be 2×{fraction (3/16)}″ flat metal segments. The center shaft at each end of the drum is supported by 1 and ¼ inch pillow block with ½×1″ slotted holes for adjustment. The drum frames to support the drum are made of 2×2×{fraction (3/16)}″ angle welded to form to rectangular sides with drum resting between, mounted on top of center support bracket, which is to be off the floor. Drum units are designed to produce at least 1150 torque horsepower. Pillow blocks for the drums are preferably cast iron such as a SAS Standard Series: SAS 1 and ¼ inch shaft OD diameter such as those with model number GYA104RRB. 
     The motor of the present invention is preferably a reversible direct drive electrical motor can be a NEMA B design, totally enclosed fan-cooled motor with helical/worm double reduction gear, having a 100 to 1 gear ratio power drive transmission. The motor frame  103  for the motor  104  is preferably 2×2×{fraction (3/16)}″ steel angle. The mount for motor preferably has at least 4″ of adjustment. 
     Preferably the new direct drive motor would require only ⅓ rd  hp providing 2800 pounds of torque for moving up to 12 rows of seats. Under previous systems, the motors would require 2 horsepower and 1200 pounds of torque to move up to 12 rows. For a telescoping seating system having up to 30 rows, previous systems required 5 horsepower motors providing 5900 pounds of torque, when in the present invention it is contemplated that with this design, only ¾ horsepower would be needed providing 7400 pounds of torque. 
     The drive shafts of the invention turn the drum. Preferred drive shafts are to be continuous 1 and ¼ inch OD cold rolled steel with flexible shaft couplings to link all drums and motors together. The shafts could be 1 inch to 1 and ⅝ inch or larger depending on the weight. At least 4 shaft couplers are shown, but depending on the length of the bleachers, more may be needed to connect the numerous shafts together. 
     This invention is contemplated for use in a wide variety of bleacher systems, from 3 to over 30 rows, and having a length of a mere 6 feet to over 180 foot lengths. For longer lengths, more drum units would be needed. It is considered that this invention would work easily with a system of up to 10 drum units, and even more, although the shaft diameters may have to be adjusted to handle the additional weight of the longer units. 
     Limit switches further control the motors. Limit switches are operably connected to the motor and are preferably fully enclosed with two operating cams. The limits of the limit switches are to be adjusted to stop bleachers automatically in the extended and closed positions based on certain preset values. Limit switches are to be operated off the drive shaft. Typical limit switches are available from Furnas such as NEMA 1 &amp; 12 industrial use 54BB23FC, NEMA 4 water flight 54BB23EC, NEMA 7 &amp; 9 54BB23HC. 
     There has thus been described a telescoping seating system having a plurality of benches wherein a direct drive motor is utilized to move the benches uniformly and simultaneously by retraction of a plurality of drive carriages which support the benches. While particular embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that changes and modifications may be made therein without departing from the invention and its broader aspects. For example, the present invention may be used with many different types of bench structures and is not limited to the seating structures described herein, as persons skilled in the art will appreciate. The appended claims, therefore, are intended to cover all such changes and modifications as fall within the true spirit and scope of the invention.