Patent Publication Number: US-7905060-B2

Title: Tiered seating system

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to tiered seating systems, and more particularly to stadium seating. 
     Tiered seating systems are widely used in venues to provide each seated person with a generally unobstructed view of a stage, a screen, a performance area, a field, or the like. These venues include auditoriums, theaters, sports arenas, classrooms, and churches. The tiered seating includes rows of seats with each row being higher than the row directly in front of it. Thus, people sitting in the seats have better views than they would if the seats were all on the same level. 
     One particularly useful type of tiered seating is known as “stadium seating.” Such seating is constructed using foam blocks, metal brackets, metal risers, and concrete. The foam blocks are stacked in a desired configuration providing the tiers. The risers are secured to the tiered foam blocks using the brackets with each riser spaced from the front of each tier. The risers provide a concrete form that remains an integral part of the construction after the concrete is cast. The top of each riser is secured to the top of the associated block using the brackets, which are attached to the riser and anchored in the block. Concrete is cast on top of the foam blocks and into the space between the risers and the foam blocks to complete the structure. After the concrete cures, seating is attached to the tiers. 
     Because the concrete is relatively heavy, it exerts a considerable force on the riser away from the blocks. The gage of the steel riser therefore is preferably sufficiently heavy to prevent the riser from visible bowing or otherwise deforming under the weight of the concrete. Consequently, the riser is relatively heavy and relatively expensive. 
     SUMMARY OF THE INVENTION 
     The present invention provides a tiered seating system enabling the riser to be of a lighter gage, so that the riser is lighter and less expensive than in previous systems. 
     The system includes a unique block and bracket construction to compensate for the lighter gage riser. Each tier includes two blocks—a lower block and an upper block. Brackets are secured between the upper and lower block and are attached to a point approximately midway along the height of the riser. Because the risers are supported both at their top (as in the prior art) and along their height, the brackets collectively provide adequate support to compensate for the reduced thickness of the riser—to prevent visual bowing or other deformation. 
     The present invention also includes a method of forming a tiered seating system using the described components. The steps of the method include positioning a lower block for each tier, positioning a riser spaced from the lower block, installing a bracket between the riser and the lower block, positioning an upper block, installing a bracket between the upper block and the riser, and casting concrete over the upper block and in the spaced between the riser and the blocks. 
     Fabricating each tier using a lower and an upper block, using brackets between the two blocks, and connecting those brackets to the riser provides an additional row of brackets supporting the riser approximately midway along its height. In combination with the conventional brackets at the top of the riser, the riser is supported against visible bowing; and the riser maintains its position with respect to the blocks when concrete is poured into the gap between the riser and the blocks. The extra support provided by the additional row of brackets allows the riser to be of reduced gage, which results in weight and cost savings, which more than offsets the weight and the cost of the additional brackets. 
     These and other objects, advantages, and features of the invention will be more fully understood and appreciated by reference to the description of the current embodiment and the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a tiered seating system supporting a plurality of seats. 
         FIG. 2  is a sectional view of a tier in the seating system of  FIG. 1 . 
         FIG. 3  is a perspective view showing the first or bottom riser secured to the bottom tier. 
         FIG. 4  is a perspective view showing the second riser partially secured to the second tier. 
         FIG. 5  is a perspective view showing the second riser further partially secured to the second tier with a middle row of brackets partially installed. 
         FIG. 6  is a perspective view showing an upper block being placed on the lower block of the second tier. 
         FIG. 7  is a perspective showing the installation of an upper row of brackets on the upper block of the second tier. 
         FIG. 8  is a perspective view of the brackets and the stake used to secure the riser to the upper and lower blocks. 
     
    
    
     DESCRIPTION OF THE CURRENT EMBODIMENT 
     A tiered seating system in accordance with the present invention is shown in  FIG. 1  and is generally designated  10 . The seating system  10  includes a plurality of seats  12  supported on a series of tiers  14 . As shown in  FIG. 2 , each of the tiers  14  include a block pair  16 , a riser  22 , and concrete  30 . The block pair  16  includes a lower block  18  and an upper block  20 . The riser  22  is spaced from a front surface  24  of the block pair  16  and is secured to both the lower block  18  and upper block  20 , respectively, by at least two brackets  26 . The brackets  26  maintain a gap  28  between the riser  22  and the block pair  16 . The gap  28  is then filled with the concrete  30 , which is also applied across an upper surface  32  of the upper block  20 , up to the height of the riser  22 . 
     As shown in  FIGS. 3-7 , the system  10  includes three partially formed tiers  14 , labeled A, B and C. In  FIG. 3 , the tier A already includes a riser  22  and is ready to receive the material  30 , while tiers B and C include only a lower block  18 . With reference to tier A, the lower and upper blocks  18  and  20  generally refer to the lower and upper halves, respectively, of the front portion of the block pair  16 . In the illustrated embodiment, the lower block  18  is generally L-shaped and forms a recess adapted to receive the upper block  20 . The upper block  20  is sized such that the front surface  34  of the upper block  20  is generally flush with the front surface  38  of the lower block  18 . Both the lower and upper blocks  18 ,  20  are formed from blocks of any suitable material, including but not limited to foam, Styrofoam or Geofoam. 
     Tiers B and C illustrate the typical first step in forming the seating system  10 , which is to stack a set of lower blocks  18  on top of one another, with the front end of each block being set back from the front end of the block directly below it. Thus, the lower blocks  18  increase in height, in the manner of a traditional set of tiers or stairs. 
     In order to maintain the positions of the stacked lower blocks  18 , the blocks  18  may be glued together, or gripper plates  68  may be included between the blocks (see  FIG. 2 ). The gripper plate  68  is formed as a generally flat plate having pointed protrusions  70  extending from both sides thereof. The pointed protrusions  70  pierce the upper surface of one lower block  18  and the bottom surface of the other lower block that is stacked on top of it, to prevent the tier portions  18  from sliding with respect to one another. The number of gripper plates  68  appropriate for each lower block  18  will depend in part on the size the tier portions  18  and  20 . Optionally, three gripper plates  68  can be used for each lower block  18 . One gripper plate  68  can be positioned within approximately six inches of the front edge near the center of the tier portion  18 , while the remaining gripper plates  68  can be positioned at the respective sides of the tier portion  18 , within approximately six inches of the front and lateral edges of the tier portion  18 . 
     The risers  22  are attached to the block pairs  16 . With reference to tier B in  FIG. 4 , the riser  22  is positioned to be spaced from the front surface  38  of the lower block  18 . In the illustrated embodiment, the riser  22  is formed as a thin metal sheet having first and second rows  40 ,  42  of retaining slots  44  defined therein. The retaining slots  44  are sized and shaped to receive a portion of the bracket  26 , which is adapted to maintain the position of the riser  22  with respect to the block pair  16 . The retaining slots  44  can be formed in the riser  22  using any known method, including metal stamping. As shown in  FIG. 4 , the riser  22  can also include at least one retaining slot  44  positioned lengthwise on or near the lateral edges  46  of the riser  22 , so that a bracket or any other type of connector can be used to secure adjacent risers  22 . Alternatively, the brackets  26  can be attached to the riser  22  using screws or bolts or any other suitable connectors, which may be formed from metal. In the illustrated embodiment, the height of the riser  22  is at least twice the height of the lower block  18 , but the present invention is not limited to that ratio. 
     The riser  22  can include an upper flange or leg  48  and a lower flange or leg  50 . For example, the upper and lower legs  48  may be included on the riser  22  in a seating system  10  having straight or upright tiers, as shown in the illustrated embodiment. In a seating system having curved tiers, the upper and lower legs  48  and  50  may not be included. In the illustrated embodiment, the lower leg  50  extends generally perpendicularly from the body of the riser  22  and is adapted to rest on the lower block  18  of the block pair  16  immediately below it. For example, with reference to tier B in  FIG. 4 , the lower leg  50  of the riser  22  rests on the lower block  18  of tier A. To maintain the position of the lower leg  50 , at least one stake  52  is pressed into the lower block  18  of tier A near the lower leg  50 . The stake  52  can include a pointed end  54  adapted to puncture the lower block  18  and a retaining end  56  adapted to engage and rest on the lower leg  50  of the riser  22  (see  FIG. 4 ). 
     The middle brackets  26  are then secured to the riser  22  to maintain the position of the riser  22  with respect to the lower block  18  of tier B. The brackets  26  can be formed in any suitable size and shape to secure the riser  22  to the lower and upper blocks  18  and  20 . Alternatively, any suitable connector or retainer can be used in place of the brackets  26 . As shown in  FIG. 8 , the brackets  26  each include a generally flat middle portion  58  and first and second flanges  60  and  62 , which extend generally perpendicular from the middle portion  58 . In the illustrated embodiment, the first and second flanges  60 ,  62  extend in opposite directions from the middle portion  58 . Optionally, the bracket  26  can also include at least one tab  64  extending from the middle portion  58 . The tabs  64  are pointed and adapted to pierce the surface of the lower and upper blocks  18 ,  20 . In the illustrated embodiment, two of the tabs  64  are punched or pressed out of the middle portion  58  of the bracket  26 , while a third tab  64  is punched or pressed out of the second flange  62 . 
     As shown in  FIG. 5 , the first flange  60  is inserted through one of the retaining slots  44  in row  40  in the riser  22 . The row  40  is located near the center of the riser  22 . The bracket  26  is oriented such that the first flange  60  and the tabs  64  are pointing generally downward. The middle portion  58  of the bracket  26  can then be pressed onto the upper surface  66  of the lower block  18 , such that the tabs  64  pierce the upper surface  66  to secure the bracket  26  to the lower block  18 . In this configuration, the tabs  64  and the first flange  60  maintain the position of the riser  22  with respect to the lower block  18 . Specifically, the tabs  64  function to resist movement of the riser  22  and bracket  26  away from the lower block  18 . As shown in  FIG. 5 , in this orientation, the second flange  62  points generally upward and perpendicular to the upper surface  66  of the lower block  18 . The number of brackets  26  appropriate to secure the riser  22  to the lower block  18  will depend in part on the size and the length of both the riser  22  and the lower block  18 . 
     The upper block  20  can then be placed on top of the lower block  18 , in the recess created by the L-shaped lower block  18  (see  FIG. 6 ). The bottom surface of the upper block  20  is pressed onto and over the second flanges  62  of the brackets  26  that secure the lower block  18  to the riser  22 . Thus, the first series of brackets  26  maintains the position of both the riser  22  and the upper block  20  with respect to the lower block  18 . In the illustrated embodiment, two upper blocks  20  cover the single lower block  18  in each of tiers A, B and C. 
     To assist in maintaining the position of the upper block  20  with respect to the lower block  18 , at least one gripper plate  68  is included on an upper surface  66  of the lower block  18 . The gripper plate  68  is substantially similar or identical to the gripper plate  68  used to maintain the stacked position of the lower blocks  18 , as described above, and includes pointed protrusions  70 , which pierce both the upper surface  66  of the lower block  18  and the bottom surface of the upper block  20  to maintain the relative positions of the upper and lower blocks  18 ,  20 . The number of gripper plates  68  appropriate to stabilize the lower and upper blocks  18  and  20  will depend in part on the size the tier portions  18  and  20 . 
     Once in place on top of the lower block  18 , the upper brackets  26  are installed to secure the riser  22  to the upper blocks  20 . The brackets  26  are substantially similar or even identical to the brackets  26  used to secure the riser to the lower block  18 , but may have a shorter length, as shown in  FIG. 2 . The brackets  26  are applied in generally the same manner as described above with respect to the lower block  18 . For example, as shown in  FIG. 7 , a series of brackets  26  are inserted into the retaining slots  44  in row  42  on the riser  22 . The row  42  is located along a second line along an upper portion of the riser  22 . The first flange  60  of the bracket  26  is inserted through the retaining slot  44 , with the first flange  60  and the tabs  64  pointing generally downward. The middle portion  58  of the bracket  26  is then pressed onto the upper surface  32  of the upper block  20 , so that at least one of the tabs  64  pierces the upper surface  32 . Thus, the tabs  64  secure the bracket  26  to the upper block  20  and function to resist movement of the riser  22  and bracket  26  away from the upper block  20 . The second flange  62  extends generally upward from and perpendicular to the top surface  32  of the upper block  20 , and can act as an anchor for the material  30  that will be poured over the block pair  16 . 
     Thus, the stakes  52 , brackets  26  and gripper plates  68  securely maintain the position of the riser  22  and the lower and upper blocks  18 ,  20 . Optionally, to assist in supporting the seats  12  after the concrete  30  is poured, bolt assemblies  72  can be secured to the riser  22  (see  FIG. 2 ). Securing the bolt assemblies  72  prior to the pouring of the material  30  can allow the concrete  30  to harden about the bolt assemblies  72  to provide a more secure and permanent connection, such that the bolt assemblies can better support the seating. 
     As shown in  FIG. 7 , the tiers A and B (once the brackets  26  have been fully inserted into the retaining slots  44  in row  42 ) are ready to receive the concrete  30 , which fills the gap  28  between the block pair  16  and the riser  22 . The concrete  30  also is poured to form a layer on the top surface  32  of the upper block  20 . In the current embodiment, concrete  30  is the preferred casting material. Other suitable materials can also be used. Because of its weight, the uncured concrete exerts a force against the riser  22  in a direction away from the block pair  16 . However, the brackets  26  assist the riser  22  in resisting this force to maintain the generally vertical position of the riser  22  with respect to the block pair  16  and to prevent bowing or other deformation. As shown in  FIG. 2 , the concrete  30  is poured to a level that is even with the upper leg  48  of the riser  22 . Optionally, side forms (not shown) can be used to contain the material  30  laterally to the desired areas in the respective tiers A and B. Once the concrete  30  hardens, the tiers  14  are capable of supporting seats, bleachers or the like. 
     The method described above, primarily with respect to tier B, can be repeated with tier C, and any additional number of tiers, as desired. 
     The above description is that of the current embodiment of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular.