Bleachers (or grandstands) provide seating for an audience for various sporting events, theatrical performances, and other similar events. Permanent bleachers are installed in gymnasiums or other locations where such events are frequent. However, for events that occur on a less frequent basis, temporary bleacher systems may be used. Such temporary bleacher systems are often mounted on some form of mobile framework for ready transport to the location of the event. Once at the appropriate location, the bleacher system can be transitioned from the transport position to a deployed position. Thus, such mobile bleacher systems provide short-term and special event seating without the time and labor required to set up conventional bleachers.
In prior art mobile bleacher systems, hydraulic actuators (or similar mechanical or electromechanical actuators) are often used to transition the bleacher system from the transport position to the deployed position, and vice versa. However, such hydraulic actuators are usually extended during transport and storage, and then retracted to transition the bleacher system to the deployed position. Because the hydraulic actuators are extended, the rods are susceptible to corrosion during transport from exposure to road salt and also susceptible to corrosion from environmental conditions during long periods of storage. Thus, expensive and maintenance-prone rod covers have often been used to address and minimize this problem.
Furthermore, in prior art mobile bleacher systems, complex actuating systems and multiple-step procedures are often required to transition the bleacher system from a transport position to a deployed position, and vice versa.
Furthermore, in prior art mobile bleacher systems, the number of rows in the bleacher system or leg room (pitch) from one seat row to the next is often sacrificed in order to make the bleacher system sufficiently compact for transport.
To address some of these deficiencies of prior art mobile bleacher systems, commonly assigned U.S. Pat. No. 8,296,999, which is incorporated herein by reference, describes a bleacher system (or grandstand) that is comprised of multiple tiers which are mounted on a support structure. The tiers are pivotally mounted to the support structure so that the bleacher system can be readily transitioned from a transport position to a deployed position. In this regard, such transition of the bleacher system from the transport position to the deployed position is achieved through the use of one or more hydraulic actuators (or similar mechanical or electromechanical actuators) that are retracted during transport and storage, and then extended to transition the bleacher system to the deployed position. Thus, the rods are protected from exposure to road salt and environmental conditions during transport and storage. Furthermore, as a result of the configuration of the tiers and their connection to the underlying support structure and each other, deployment requires only a single actuating action. At the same time, there is no sacrifice in the number of rows in the bleacher system or leg room (pitch) from one seat row to the next.
As described in U.S. Pat. No. 8,296,999, in one embodiment, an exemplary bleacher system includes three tiers that are mounted to an underlying support structure, which includes two parallel I-beams (or longitudinal rails) that are spaced from one another and extend the length of the bleacher system, effectively creating a complete trailer frame. Multiple cross members extend between and connect the longitudinal rails along the length of the bleacher system. Wheels and an associated suspension system are mounted to the longitudinal rails to facilitate transport of the bleacher system.
Each tier is then generally constructed of multiple girders at spaced intervals that are operably connected to the underlying support structure. Each girder in each tier supports multiple seat supports and foot board supports, with respective seat planks and foot planks then being secured to the respective seat supports and foot board supports and extending along the length of the bleacher system over such seat supports and foot board supports.
Each girder of the upper tier is connected to a rear strut by a pin connection defining a pivot point. The pivot points defined by the respective pin connections are aligned and effectively define an axis of rotation along the length of the bleacher system. Each rear strut is also connected to the underlying support structure by a pin connection defining another pivot point.
The upper tier is connected to the middle tier by a pin connection defining a pivot point. Again, there are actually multiple such pin connections and associated pivot points that are aligned along the length of the bleacher system that effectively define an axis of rotation along the length of the bleacher system. Furthermore, each girder of the middle tier includes a generally triangular-shaped strut. The pivot point is at a rear corner of this strut, and a lower corner of this strut is mounted to the underlying support structure for rotation about a main pivot point, such that the middle tier can effectively rotate about the main pivot point.
The lower tier is connected to the middle tier by a pin connection defining a pivot point. Again, there are actually multiple such pin connections and associated pivot points that are aligned along the length of the bleacher system that effectively define an axis of rotation along the length of the bleacher system.
With respect to the transition of the bleacher system from the transport position to the deployed position, and vice versa, there is a deployment link support structure that is secured to or integral with the underlying support structure for each hydraulic actuator. Each hydraulic actuator is connected to a respective deployment link support structure at a first end by a pin connection defining a pivot point. The rod of the hydraulic actuator is then connected to the middle tier by a pin connection defining a pivot point.
Furthermore, for each hydraulic actuator, a deployment link is connected to the deployment link support structure by a pin connection defining a pivot point. Each such deployment link extends toward the lower tier with its distal end being connected to a second, shorter deployment link by a pin connection defining a pivot point. The opposite end of this second, shorter deployment link is then connected to the girder of the lower tier by a pin connection defining a pivot point.
In operation, when transitioning from the deployed position to the transport position, each hydraulic actuator is activated in unison, and the respective rods of the hydraulic actuators begin to retract. As the rods retract, the middle tier begins rotating backward about the main pivot point. As a result, the respective pivot points at the pin connections between the middle tier and the lower tier are moved upward, and thus, the lower tier begins rotating toward the middle tier. At the opposite end of the middle tier, the respective pivot points at the pin connections between the middle tier and the upper tier are moved downward. The upper tier thus begins rotating forward. Such simultaneous rotation of the three tiers continues as the rods of the hydraulic actuators retract. Furthermore, once tension is released in the connection between the deployment link and the second, shorter deployment link, these two components begin to rotate and “fold” relative to one another. Rotation of the three tiers ceases when the rods of the hydraulic actuators are fully retracted, at which time the rear struts are each in an upright orientation substantially perpendicular to the underlying support structure, and the bleacher system is in the transport position.
To transition the bleacher system from the transport position back to the deployed position, the respective rods of the hydraulic actuators are extended. The rods effectively push against the middle tier, causing the middle tier to rotate forward about the main pivot point. As a result, the respective pivot points at the pin connections between the middle tier and the lower tier are moved downward, and at the same time, the lower tier begins rotating away from the middle tier. As the lower tier rotates away from the middle tier, the deployment link and the second, shorter deployment link rotate into an aligned position, pushing the lower tier into the deployed position. At the opposite end of the middle tier, the respective pivot points at the pin connections between the middle tier and the upper tier are moved upward. The upper tier thus begins rotating backward. Rotation of the three tiers continues until the rods of the hydraulic actuators are fully extended, and the bleacher system is in the deployed position.
As described in U.S. Pat. No. 8,296,999, in another embodiment, an exemplary bleacher system includes two tiers that are mounted to an underlying support structure, which again includes two parallel I-beams (or longitudinal rails) that are spaced from one another and extend the length of the bleacher system, effectively creating a complete trailer frame. Multiple cross members extend between and connect the longitudinal rails along the length of the bleacher system. Wheels and an associated suspension system are mounted to the longitudinal rails to facilitate transport of the bleacher system.
Each tier is again constructed of multiple girders at spaced intervals that are operably connected to the underlying support structure. Each girder in each tier supports multiple seat supports and foot board supports, with respective seat planks and foot planks then being secured to the respective seat supports and foot board supports and extending along the length of the bleacher system over such seat supports and foot board supports.
Each girder of the upper tier is connected to a rear strut by a pin connection defining a pivot point. The pivot points defined by the respective pin connections are aligned and effectively define an axis of rotation along the length of the bleacher system. Each rear strut is also connected to the underlying support structure by a pin connection defining another pivot point.
The upper tier is connected to the lower tier by a pin connection defining a pivot point. Again, there are actually multiple such pin connections and associated pivot points that are aligned along the length of the bleacher system that effectively define an axis of rotation along the length of the bleacher system. Specifically, each girder of lower tier includes a vertical extension. The pin connection defining the pivot point between the upper tier and the lower tier at each girder is at a first end of this vertical extension, while the opposite end of the vertical extension is connected by a pin connection defining a pivot point to the underlying support structure.
With respect to the transition of the bleacher system from the transport position to the deployed position, and vice versa, a hydraulic actuator is connected to a plate (which is secured to and extends from the support structure) at a first end by a pin connection defining a pivot point. The rod of the hydraulic actuator is then connected to the lower tier by a pin connection defining a pivot point.
In operation, when transitioning from the deployed position to the transport position, when each hydraulic actuator is activated, the respective rods of the hydraulic actuators begin to retract. As the rods begin to retract, the lower tier begins rotating backward. As a result, the respective pivot points at the pin connections between the upper tier and the lower tier are moved downward, and thus, the upper tier begins rotating toward the lower tier. At the same time, the rear struts also begin rotating backward. Such simultaneous rotation of the upper tier and the lower tier continues as the rods of the hydraulic actuators retract. Rotation of the upper tier and the lower tier ceases when the rods of the hydraulic actuators are fully retracted, and the bleacher system is in the transport position.
However, it remains desirable to further simplify the operation of a mobile bleacher system and to incorporate refinements that facilitate the transport and deployment of a mobile bleacher system. Furthermore, some such refinements have applicability to other forms of bleacher systems, including those bleacher systems in which one or more tiers are fixed to the underlying support structure.
The present invention is bleacher system.
An exemplary bleacher system made in accordance with the present invention includes two tiers—an upper tier and a lower tier. These two tiers are mounted to an underlying support structure, but unlike the bleacher systems described in U.S. Pat. No. 8,296,999, the support structure in the bleacher system of the present invention does not include a separate, complete trailer frame. Rather, in the bleacher system of the present invention, the support structure includes multiple cross members at spaced intervals from one another, but no longitudinal rails that interconnect and provide support to the cross members. The support structure further includes an axle carrier sub-frame which is positioned between two of the cross members of the support structure (as further described below).
The upper tier is constructed from multiple girders at spaced intervals. Each girder supports multiple seat supports and foot board supports, with respective seat planks (or seats) and foot planks then being secured to the respective seat supports and foot board supports and extending along the length of the bleacher system over such seat supports and foot board supports.
Similarly, the lower tier is constructed from multiple girders at spaced intervals. Each girder supports multiple seat supports and foot board supports, with respective seat planks (or seats) and foot planks then being secured to the respective seat supports and foot board supports and extending along the length of the bleacher system over such seat supports and foot board supports.
A rear strut is associated with each girder of the upper tier. In some embodiments, the rear strut terminates in a slide plate (or bearing) that engages and supports the girder. In other embodiments, each rear strut is connected to a girder of the upper tier by a pin connection defining a pivot point, and then is connected to a respective cross member of the underlying support structure by a pin connection defining another pivot point. In either case, there are multiple rear struts, one associated with each girder of the upper tier along the length of the bleacher system. When the bleacher system is in the deployed position, each rear strut thus extends from the girder of the upper tier to a respective cross member of the support structure.
The upper tier is connected to the lower tier by a pin connection defining a pivot point. There are multiple such pin connections and associated pivot points that are aligned along the length of the bleacher system that effectively define an axis of rotation along the length of the bleacher system. Each girder of the lower tier is then connected by a pin connection defining a pivot point to a respective cross member of the support structure.
With respect to the transition of the bleacher system from the transport position to the deployed position, and vice versa, a hydraulic actuator (or similar mechanical or electromechanical actuator) extends between a respective cross member of the support structure and the lower tier. In operation, when transitioning from the deployed position to the transport position, the hydraulic actuator is activated, and the rod of the hydraulic actuator begins to retract. As the rod begins to retract, the lower tier begins rotating about an axis of rotation. As a result, the respective pivot points at the pin connections between the upper tier and the lower tier are moved downward, and thus, the upper tier begins rotating toward the lower tier. In other words, the extension of the rod of the hydraulic actuator causes the lower tier to pivot relative to the support structure in a first direction, while causing the upper tier to pivot relative to the support structure in an opposite direction. Such simultaneous rotation of the upper tier and the lower tier continues as the rod of the hydraulic actuator retracts. Rotation of the upper tier and the lower tier ceases when the rod of the hydraulic actuator is fully retracted, and the bleacher system is in the transport position.
During the transition of the bleacher system from the deployed position to the transport position, a front jack (or support leg) and a rear jack (or support leg) associated with each cross member are also moved into a transport position. Specifically, the front jack is pivotally connected to the cross member at the main pivot, i.e., at the pin connection between each girder of the lower tier and the cross member. The rear jack is pivotally connected to the cross member near the rear strut. A jack link then extends between and connects the front jack to a jack link driver, which, in turn, is connected to the rear jack. Thus, in operation, when the lower tier begins rotating, the front jack also begins to rotate, and as result of the use of the jack link and the jack link driver, the rear jack rotates with the front jack.
During the transition of the bleacher system from the deployed position to the transport position, the front jack and the rear jack rotate to a substantially horizontal orientation for transport.
During the transition of the bleacher system from the transport position to the deployed position, the front jack and the rear jack rotate to a substantially vertical orientation for engaging the underlying ground surface and providing support to the bleacher system.
Returning now to the support structure of the bleacher system, as stated above, the support structure includes multiple cross members at spaced intervals from one another, along with and an axle carrier sub-frame which is positioned between two of the cross members. The axle carrier sub-frame is comprised primarily of two beams that extend between and are connected to two of the cross members of the support structure and are oriented substantially perpendicular to the cross members.
The ends of the two beams are substantially identical to one another. Specifically, each end of each beam terminates in a bracket. The bracket defines a hole for receiving a tube, which then also passes through a corresponding hole defined by an adjacent cross member, thus connecting the beam to the cross member. In some embodiments, the tube also defines the pin connection between the girder of the lower tier and the cross member of the support structure. In some embodiments, the tube also passes through the front jack, thus creating the pivot connection between the front jack and the cross member.
Finally, the support structure also includes appropriate brackets mounted to the two beams to accommodate an axle to mount and drive the wheels of the bleacher system.
As a further refinement, a bleacher system made in accordance with the present invention may include a retractable hitch tube for supporting a hitch that enables the bleacher system to be towed behind a truck. Specifically, when the bleacher system is in a transport position, the hitch tube, which has a hitch at its distal end, extends from the front of the bleacher system (i.e., an extended position) so that the hitch can be readily connected to a truck, and the bleacher system can be towed behind the truck. However, when the bleacher system is in a deployed position, the hitch tube can be retracted into the bleacher system (i.e., a retracted position). Use of such a hitch tube eliminates further weight and costs associated with a separate hitch support structure.
Referring first to
Referring still to
Similarly, the lower tier 60 is constructed from multiple girders 70 at spaced intervals. Each girder 70 supports multiple seat supports 72 and foot board supports 74, with respective seat planks (or seats) 73 and foot planks 75 then being secured to the respective seat supports 72 and foot board supports 74 and extending along the length of the bleacher system 10 over such seat supports 42 and foot board supports 74.
A rear strut 32 is associated with each girder 40 of the upper tier 30. The rear strut 32 terminates in a slide plate (or bearing) 33 that engages and supports the girder 40, but, in this exemplary embodiment, is not attached to the girder 40. As shown in
The upper tier 30 is connected to the lower tier 60 by a pin connection defining a pivot point 62 (i.e., “tiers pivot”). There are actually multiple such pin connections and associated pivot points 62 that are aligned along the length of the bleacher system 10 that effectively define an axis of rotation along the length of the bleacher system 10. Specifically, each girder 70 of the lower tier 60 includes a vertical extension 71. The pin connection defining the pivot point 62 between the upper tier 30 and the lower tier 60 at each girder 70 is at an upper end of this vertical extension 71. Each girder 70 of the lower tier 60 is then connected by a pin connection defining a pivot point 64 to a respective cross member 25 of the support structure 20.
Now, with respect to the transition of the bleacher system 10 from the transport position to the deployed position, and vice versa, a hydraulic actuator 140 (or similar mechanical or electromechanical actuator) extends between a respective cross member 25 of the support structure 20 and the lower tier 60. Specifically, in this exemplary embodiment, the hydraulic actuator 140 is connected to the cross member 25 at a first end by a pin connection defining a pivot point 122. The rod 142 of the hydraulic actuator 140 is then connected to the lower tier 60 by another pin connection defining a pivot point 124.
Because of this construction, the bleacher system 10 can be readily transitioned from the transport position to the deployed position by extending the hydraulic actuator 140.
Referring now to
Such simultaneous rotation of the upper tier 30 and the lower tier 60 continues as the rod 142 of the hydraulic actuator 140 retracts. As shown in
Referring still to
During the transition of the bleacher system 10 from the deployed position to the transport position, the front jack 150 and the rear jack 152 rotate (counterclockwise in
During the transition of the bleacher system 10 from the transport position to the deployed position, the front jack 150 and the rear jack 152 rotate (clockwise in
The use of such front and rear jacks 150, 152 along the length of the bleacher system 10 allows, in part, for the reduction of size of the cross members 25 of the support structure 20, as the front and rear jacks 150, 152 reduce loads and bending stresses on the cross members 25. Such a reduction of size (and weight) can thus allow for more seat rows, increased seat spacing, or additional leg room from one seat row to the next, but without increasing the overall height of the bleacher system 10 in the transport position.
As shown in
Referring still to
In this exemplary embodiment, the tube 21 shown in
Referring now to
Referring again to
Referring again to
As a result of such construction and the positioning of the axle carrier sub-frame 22, there is a direct load path between the axle carrier sub-frame 22 and respective tiers 30, 60 of the bleacher system. Thus, in a transport position, the tiers 30, 60 of girders, seat supports, and foot board supports are effectively supported by the axle carrier sub-frame 22 and the cross members 25. It is not necessary for the support structure 20 to include parallel I-beams or any similar longitudinal rails along the length of the bleacher system 10. In other words, it is not necessary to build a complete trailer frame under the tiers 30, 60, as the tiers 30, 60 of girders, seat supports, and foot board supports effectively form a trailer frame in the transport position.
Furthermore, and as shown in
As a further refinement, and as shown in
As a further refinement, and referring now to
Unlike the construction described above with respect to
The upper tier 230 is again connected to the lower tier 260 by a pin connection defining a pivot point 262 (i.e., “tiers pivot”). Again, there are actually multiple such pin connections and associated pivot points 262 that are aligned along the length of the bleacher system 210 that effectively define an axis of rotation along the length of the bleacher system 210. Each girder 270 of the lower tier 260 is then connected by a pin connection defining a pivot point 264 to a respective cross member 225 of the support structure 220.
Referring still to
Referring still to
During the transition of the bleacher system 210 from the deployed position to the transport position, the front jack 350 and the rear jack 352 rotate (counterclockwise in
During the transition of the bleacher system 210 from the transport position to the deployed position, the front jack 350 and the rear jack 352 rotate (clockwise in
A rear strut 432 is associated with each girder 440 of the upper tier 430. The rear strut 432 terminates in a slide plate (or bearing) 433 that engages and supports the girder 440, but, in this exemplary embodiment, is not attached to the girder 440. Again, there are actually multiple rear struts 432, one associated with each girder 440 along the length of the bleacher system 410. When the bleacher system 410 is in the deployed position, each rear strut 432 thus extends from girder 440 of the upper tier to a respective cross member 425 of the underlying support structure 420, where it is connected to the support structure 420.
The upper tier 430 is again connected to the lower tier 460 by a pin connection defining a pivot point 462 (i.e., “tiers pivot”). Again, there are actually multiple such pin connections and associated pivot points 462 that are aligned along the length of the bleacher system 410 that effectively define an axis of rotation along the length of the bleacher system 410. Each girder 470 of the lower tier 460 is then connected by a pin connection defining a pivot point 464 (“main pivot”) to a respective cross member 425 of the support structure 420.
In this exemplary embodiment, however, there are ten rows of seats. To provide the proper mechanical advantage to transition the bleacher system 410 from the transport position to the deployed position, and vice versa, a front strut 426, which, in this case, has a triangular shape, extends upwardly from a cross member 425 of the support structure 420. One end of the hydraulic actuator 540 is connected to a vertex of the front strut 426 by a pin connection defining a pivot point 522. The rod 542 of the hydraulic actuator 540 is then connected to the lower tier 460 by another pin connection defining a pivot point 524. Thus, the pivot point 522 is at a higher elevation as compared to the analogous pivot point 122 for the exemplary embodiment (eight rows of seats) described above with respect to
When transitioning from the deployed position to the transport position, the hydraulic actuator 540 is activated, and the rod 542 of the hydraulic actuator 540 begins to retract. As the rod 542 begins to retract, the lower tier 460 begins rotating backward (counterclockwise in
Referring still to
During the transition of the bleacher system 410 from the deployed position to the transport position, the front jack 550 and the rear jack 552 rotate (counterclockwise in
During the transition of the bleacher system 410 from the transport position to the deployed position, the front jack 550 and the rear jack 552 rotate (clockwise in
The bleacher system 610 functions and transitions from the deployed position to the transport position, and vice versa, in the same manner as the embodiments described above with respect to
With respect to the lowest row of seats 643a in the upper tier 630, the seat supports 642a are pivotally connected to a respective girder 640. A link 684a then extends between and is pivotally connected to the seat support 642a and the respective girder 670 of the lower tier 660, near the pin connection 662 between the upper tier 630 and the lower tier 660. Thus, as shown in
With respect to the row of seats 673a in the lower tier 660, the seat supports 672a are pivotally connected to a respective girder 670. A first link 682a is pivotally connected to the support structure 620 at a first end and is then connected to a second link 683a at its opposite end. The second link 683a is then connected to the seat supports 672a. Thus, as shown in
Similarly, with respect to the row of seats 673b in the lower tier 660, the seat supports 672b are pivotally connected to a respective girder 670. A first link 682b is pivotally connected to the support structure 620 at a first end and is then connected to a second link 683b at its opposite end. The second link 683b is then connected to the seat supports 672b. Thus, as shown in
Finally, in the above-described exemplary embodiments, the tiers rotate relative to the support structure in the transition of the bleacher system from the deployed position to the transport position, and vice versa, and such rotation of the tiers is mechanically actuated. However, the refinements described above are not necessarily limited to such bleacher systems. For instance, it is contemplated that bleacher systems with one or more fixed tiers, along with bleacher systems with one or more tiers that are manually moved between a deployed position and a transport position could also be similarly constructed with some combinations of the above-described support structure, front jacks, rear jacks, and/or retractable hitch tube of the present invention.
One of ordinary skill in the art will recognize that additional embodiments and configurations are also possible without departing from the teachings of the present invention or the scope of the claims which follow. This description, and particularly the specific details of the exemplary embodiments disclosed, is given primarily for clarity of understanding, and no unnecessary limitations are to be understood therefrom, for modifications will become obvious to those skilled in the art upon reading this disclosure and may be made without departing from the spirit or scope of the claimed invention.
The present application claims priority to U.S. Provisional Patent Application Ser. No. 61/745,956 filed on Dec. 26, 2012, the entire disclosure of which is incorporated herein by reference.
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Entry |
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Century Industries, LLC, Transport Mobile Bleachers Model TSP 300 Product Sheet. |
Century Industries, LLC, Transport Mobile Bleachers Model TSP 180 Product Sheet. |
Century Industries, LLC, Transport Mobile Bleachers Model TSP 260 Product Sheet. |
Number | Date | Country | |
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61745956 | Dec 2012 | US |