Patent Publication Number: US-9409755-B2

Title: Platform safety enclosure

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims filing benefit of previously filed U.S. Provisional Patent application Ser. No. 61/861,693 having a filing date of Aug. 2, 2013, incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention generally relates to a platform safety enclosure. More particularly, this invention relates to a platform safety enclosure having a floor access panel. 
     BACKGROUND OF THE INVENTION 
     In general, elevating or elevated platforms are used to access manways and/or other equipment such as valves and fittings that are positioned along a top portion of a container vessel, for example, such as a tank trailer, a tanker rail car and/or an isotainer. Typically, the top portions of these container vessels are rounded, thereby creating a potential fall hazard for operators working aloft. As a result, many elevating and/or elevated platforms include a platform safety enclosure. 
     A conventional platform safety enclosure includes a floor or platform, a series of handrails that extend around an outer perimeter of the floor and a gangway to allow for access onto the floor. The floor may include one or more access panels. Because the floor and access panels are weight-bearing elements, the floor and access panels typically are made of strong, rigid material such as steel. Though the access panels tend to be relatively heavy, they may be raised manually to an open position to provide for access to the manways and/or other equipment of the container vessel. Each access panel may be raised individually, and two or more access panels may be raised together simultaneously as a group of access panels. Unopened access panels and/or stationary panels provide a safe working/standing surface for the operators working on the platform. 
     In use, an operator raises the appropriate access panel and rests it along the handrail. A D-ring, chain and/or other device may be used to secure the access panel to the handrail, thereby preventing an accidental closure. Once the operator has completed his tasks, he must manually disconnect the access panel from the handrail and lower it back into position. This prevents a potentially dangerous open floor situation where an operator may inadvertently fall through an open access panel. This is particularly important when the platform is being used during low light and/or low visibility conditions. 
     One issue that arises with current platform safety enclosure designs occurs when operators occasionally forget to manually disconnect the access panels and to lower the access panel or panels back into a closed position, thereby potentially creating a fall and/or a trip hazard. Another issue occurs when the operator allows the access panel to free fall back into a closed position. Over time, this can cause significant damage to the access panels, thereby requiring costly repairs and extended down time for the elevating platform. Currently, repair and replacement often requires erection of expensive scaffolding which increases the time required to repair. Another concern arises when the opened access panel accidentally closes while an operator is positioned underneath, thereby potentially causing bodily injury. 
     BRIEF DESCRIPTION OF THE INVENTION 
     Aspects and advantages of the invention are set forth below in the following description, or may be obvious from the description, or may be learned through practice of the invention. 
     One embodiment of the present invention is a platform safety enclosure. The platform safety enclosure includes a support frame having a laterally extending inner portion, a laterally extending outer portion and a pair of transversely extending side portions disposed at laterally opposing ends of the support frame. A handrail system extends laterally along the outer portion and transversely along the pair of side portions. A floor portion is carried by and extends laterally and transversely across the support frame to at least partially define a walking and/or a working surface. The floor portion includes at least one access panel and desirably a plurality of access panels. Each access panel includes a fixed end portion and an opposing free end portion. The fixed end portion is pivotally coupled to the support frame, and the free end portion is moveable between the handrail and the floor portion. Each access panel can be raised separately and held in the raised and open position by a latch mechanism. Provision is made so that lowering of each access panel to the closed position can be effected by disengaging the latch mechanism. Each latch mechanism of each access panel can be disengaged manually and separately from each other latch mechanism of each other access panel. Moreover, provision is made so that all of the latch mechanisms of all of the access panels can be disengaged simultaneously, and such simultaneous disengagement of all of the latch mechanisms can be effected automatically and from a location that is remote from the platform safety enclosure. The platform safety enclosure further includes a damper for controlling a closure velocity of the access panel as it pivots from an open or raised position to a closed and/or a partially closed position. The damper includes a first end that is coupled to the support frame and a second end that is coupled to the access panel. 
     Another embodiment of the present invention is an elevating platform. The elevating platform includes a vertical lift mechanism and a platform safety enclosure that is carried by the vertical lift mechanism and desirably is configured as described above. The platform safety enclosure defines a walking and/or a working platform of the elevating platform. The platform safety enclosure includes a support frame that is connected to the vertical lift mechanism. 
     Those of ordinary skill in the art will better appreciate the features and aspects of such embodiments, and others, upon review of the specification. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A full and enabling disclosure of the present invention, including the best mode thereof to one skilled in the art, is set forth more particularly in the specification, including reference to the accompanying figures, in which: 
         FIG. 1  illustrates a back side perspective view of an exemplary platform safety enclosure according to various embodiments of the present invention; 
         FIG. 2  illustrates a front side perspective view of the platform safety enclosure as shown in  FIG. 1 ; 
         FIG. 3A  illustrates a partial perspective view of components of the platform safety enclosure shown in  FIG. 1 , according to one embodiment of the present invention; 
         FIG. 3B  illustrates an enlarged view of a portion of the platform safety enclosure as circumscribed by line B as shown in  FIG. 3A , according to one embodiment of the present invention; 
         FIG. 3C  illustrates an enlarged view of a portion of the platform safety enclosure as circumscribed by line C as shown in  FIG. 3A , according to one embodiment of the present invention; 
         FIG. 4A  illustrates a front side partial perspective view of the platform safety enclosure including an actuating mechanism that is coupled to a latch according to one embodiment of the present invention; 
         FIG. 4B  illustrates an enlarged view of a portion of the platform safety enclosure including a portion of the actuating mechanism in a latched position as circumscribed by line B and as shown in  FIG. 4A , according to one embodiment of the present invention; 
         FIG. 4C  illustrates an enlarged view of the portion of the platform safety enclosure as shown in  FIG. 4B , but with the actuating mechanism in an open or unlatched position; and 
         FIG. 5  presents a perspective view that schematically illustrates one embodiment of an elevating platform according to the present invention and including the platform safety enclosure as shown in  FIGS. 1 and 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made in detail to present embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical designations to refer to features in the drawings. Like or similar designations in the drawings and description have been used to refer to like or similar parts of the invention. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that modifications and variations can be made in the present invention without departing from the scope or spirit thereof. For instance, features illustrated or described as part of one embodiment may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents. 
     Referring now to the drawings,  FIG. 1  illustrates a back side perspective view of an exemplary platform safety enclosure  10  according to various embodiments of the present invention. The platform safety enclosure  10  defines a lateral direction. L, a transverse direction T and a vertical direction V where each direction is mutually perpendicular and forms an orthogonal direction system. As shown in  FIG. 1 , the platform safety enclosure  10  includes a support frame  12 . The support frame  12  generally includes a laterally extending inner portion  14 , a laterally extending outer portion  16  and a pair of side portions  18 ,  20  that extend transversely between the inner portion  14  and the outer portion  16  at laterally opposing ends of the support frame  12 . 
     As shown in  FIG. 1 , a floor portion  22  extends laterally and transversely between the inner portion  14 , the outer portion  16  and the side portions  18 ,  20  of the support frame  12 . The floor portion  22  at least partially defines a generally level walking and/or working surface  24  of the platform safety enclosure  10 . The floor portion  22  may include one or more floor panels  26 . Each floor panel  26  desirably may include anti-skid surface features (not shown), drainage features (not shown) or the like so as to prevent slippage along the working surface  24 . Each floor panel  26  may be fixed in position or may be movable. 
     In particular embodiments, as shown in  FIG. 1  for example, the floor portion  22  desirably includes a plurality of access panels  28 . Each access panel  28  is configured to be pivotable between an open position and a closed position with respect to the support frame  12 . When positioned in a closed position, each access panels  28  extends in the transverse direction T between the inner portion  14  and the outer portion  16  of the support frame  12  and at least partially defines the walking surface  24 . Desirably, the plurality of access panels  28  is sufficient in number to cover the entire length (lateral dimension) of the floor portion  22  when arranged side-by-side as shown in  FIG. 1  for example. When raised to a fully open position, the access panels  28  extend upwardly in the vertical direction V from the support frame  12  to allow for access through the floor portion  22  of the platform safety enclosure  10 . 
       FIG. 2  illustrates a front side perspective view of the platform safety enclosure  10  as shown in  FIG. 1 . In one embodiment, as shown in  FIGS. 1 and 2 , the platform safety enclosure  10  includes a handrail system  30 . The handrail system  30  extends at least partially around the floor portion  22  of the platform safety enclosure  10 . For example, as shown in  FIGS. 1 and 2 , the handrail system  30  may extend in the lateral direction L along the outer portion  16  of the support frame  12  and in the transverse direction T along each side portion  18 ,  20  of the support frame  12 . The handrail system  30  may at least partially define the side portions  18 ,  20  of the support frame  12 . 
     As shown in  FIG. 2 , the handrail system  30  generally includes one or more supports  32  that extend generally upwardly in the vertical direction V from the support frame  12  and/or the floor portion  22  of the platform safety enclosure  10 . A handrail  34  extends between the supports  32  to at least partially define a cage or enclosure. The cage at least partially surrounds the floor portion  22  of the platform safety enclosure  10 . As is conventional, the support frame  12 , floor portion  22 , access panels  28  and handrail system  30  can be made of metal such as steel. However, lighter weight materials such as aluminum or carbon fiber resin matrices might be used. 
       FIG. 3A  illustrates a partial perspective view of components of the platform safety enclosure  10  as shown in  FIG. 1 , with a portion of the handrail system  30  removed and including five exemplary access panels  28  configured identically according to various embodiments of the present invention.  FIG. 3B  illustrates an enlarged view of a portion of the platform safety enclosure  10  as circumscribed by line B as shown in  FIG. 3A , and  FIG. 3C  illustrates an enlarged view of a portion of the platform safety enclosure  10  as circumscribed by line C as shown in  FIG. 3A . In particular embodiments, as shown in  FIG. 3A , each access panel  28  includes a fixed end portion  36  and a free end portion  38 . The fixed end portion  36  is pivotally coupled to the support frame  12  so as to be constrained to swing in a relatively smaller arc than the swing arc of the free end portion  38 . For example, in one embodiment, as shown in  FIG. 3A , the fixed end portion  36  is pivotally coupled to the outer portion  16  of the support frame  12 . As shown in  FIG. 3A , the free end portion  38  of each access panel  28  desirably is received by and rests against a lip flange  15  carried by the support frame  12  when the access panel  28  is deployed in the closed position to form part of the walking surface  24  of the floor portion  22 . 
     In particular embodiments, as detailed in  FIG. 3B , the fixed end portion  36  is pivotally coupled to the support frame  12  via one or more hinge joints  42 . Each hinge joint  42  may be at least partially defined by the support frame  12  and partially defined by the access panel  28 . As shown in  FIG. 3B  for example, a pivot pin  40  extends through a respective hinge joint  42 . As shown in  FIG. 3A , the pivot pins  40  and the hinge joints  42  are positioned so as to be accessible from the walking surface  24  of the floor portion  22  when the access panel  28  is in a fully raised or open position or in an at least partially raised or open position. As a result, an operator and/or repair technician may remove the access panel  28  for repair, replacement and/or disassembly while positioned on the working surface  24 , thereby eliminating the need for expensive scaffolding currently required for repair, replacement and/or disassembly of access panels of conventional platform safety enclosures. 
     A mechanism is provided for restraining each access panel  28  in the open position against the hand rail system  30 . In particular embodiments such as shown in  FIG. 3A  and detailed in  FIG. 3C , the platform safety enclosure  10  desirably includes a latch  50  and the access panel  28  includes a latching feature  52  that is attachable and detachable to the latch  50  as selected by the user. In particular embodiments, the platform safety enclosure  10  desirably may include a plurality of latches  50 , with one latch  50  being positioned along the hand rail system  30  for each respective access panel  28 . The latch  50  may be a spring loaded latch, a magnetic latch or any type of latch suitable for the purpose described herein. In one embodiment, the latch  50  is connected to the handrail system  30 . For example, the latch  50  may extend outwardly in the transverse direction or the lateral direction from the handrail  34  toward the interior of the platform safety enclosure  10 . 
     As schematically shown in  FIG. 3A  and detailed in  FIG. 3C , the access panel  28  includes a latching feature  52  that desirably includes a latch pin  54  or the like that is configured to engage with the latch  50  when the access panel  28  is in a fully open position. The latch feature  52  desirably may be disposed proximate to the free end portion  38  of the access panel  28 . The latch  50  and the latching feature  52  are configured so that their engagement and disengagement is selectively determined by the user. Suitable latches  50  that selectively grip or release the latch pin  54  at the user&#39;s option are available from Stanley-National Hardware of 480 Myrtle Street, New Britain, Conn. 06053. 
     As schematically shown in  FIG. 3A , the user may manually lift an access panel  28  from the dosed position, pivot the access panel  28  toward the hand rail system  30  and push the access panel  28  against the handrail  34 . In so doing, the user may thrust the latch pin  54  of the latching feature  52  into the grasp of the latch  50  as schematically shown in  FIGS. 3A and 3C . Whereupon as schematically shown in  FIG. 3C , a retaining detent  51  of the latch  50  prevents movement of the latch pin  54  out of the grasp of the latch  50  and thus holds the access panel  28  in the fully open position against the handrail  34 . Each access panel  28  desirably is pivotally mounted with the free end portion  38  disposed slightly off vertical in the direction of the interior of the platform safety enclosure  10  so that in the absence of the latch pin  54  being held in the grasp of a latch  50 , the weight of the access panel  28  suffices to move the access panel  28  toward the floor portion  22  under the influence of the force of gravity. 
     To release the latch pin  54  of the access panel  28  from the grasp of the latch  50  in order to move the access panel  28  away from the open position and the handrail  34  and toward the closed position, the user can tug manually on a release member  64  that retracts the retaining detent  51  of the latch  50 , thereby opening the latch  50  and allowing the user manually to move the access panel  28  away from the handrail  34  and eventually to a closed position forming part of the walking surface  24  of the floor portion  22 . 
     However, in accordance with the present invention, a plurality of the access panels  28  can be released simultaneously from their open positions. Moreover, such simultaneous release of a plurality of the access panels  28  that are held in an open position can be performed by the user from a location that is remote from the platform safety enclosure  10 .  FIG. 4A  illustrates a front side partial perspective view of the platform safety enclosure  10  including an actuating mechanism  56  that is coupled to a plurality of latches  50  and is configured to open all of these coupled latches  50  simultaneously according to one embodiment of the present invention.  FIG. 4B  illustrates an enlarged view of a portion of the platform safety enclosure  10  including a portion of the actuating mechanism  56  when one of the plurality of latches  50  remains in a latched position as circumscribed by line B shown in  FIG. 4A .  FIG. 4C  illustrates an enlarged view of a portion of the platform safety enclosure  10  as shown in  FIG. 4B  but with the actuating mechanism  56  in an open or unlatched position. The actuating mechanism  56  may be mechanically actuated, electrically actuated, pneumatically actuated or manually actuated according to the selection of the operator. 
     In one embodiment, as detailed in  FIGS. 4B and 4C , the actuating mechanism  56  may include a rotatable rod or shaft  58  that is rotatably coupled to the handrail system  30 , a pivot plate  60  that is rigidly connected to the rod  58  and that does not rotate with respect to the rod  58 , and a mechanical linkage  62  having one end that is non-rotatably connected to one end of the rod  58 . As shown in  FIG. 2 , the rod  58  and connected pivot plate  60  associated with each mechanical linkage runs down the handrail  34  past a plurality of access panels  28  and associated latches  50 . As shown in  FIG. 1 , the actuating mechanism  56  is coupled mechanically to each latch  50  via a release member  64  such as a rod, wire, chain, rope or the like. In the alternative, the actuating mechanism  56  may be magnetically coupled to each latch  50  that is included in the plurality of latches  50  serviced by the actuating mechanism  56 . The actuating mechanism  56  is configured to open each of the plurality of associated latches  50  when the actuating mechanism  56  is engaged or actuated as shown in  FIG. 4C , thereby releasing each of the plurality of access panels  28  associated with that actuating mechanism  56 . Depending on the number of access panels  28 , their sizes and weights, more than one actuating mechanism  56  and associated groupings of a plurality of access panels may be desired for a particular platform safety enclosure  10 , and two actuating mechanisms  56  are employed by the embodiment of the platform safety enclosure  10  depicted in  FIG. 2  for example. 
     In one embodiment, as detailed in  FIGS. 4B and 4C , the mechanical linkage  62  desirably includes a linkage arm  63  that is rigidly and non-rotatably attached to one end of the rotatable rod  58 . The other end of the linkage arm  63  is pivotally connected to one end of an actuator rod  69  of an actuator cylinder  68 , which in turn is pivotally connected at one end to a bracket  66 . In various embodiments, the actuator  68  may be a pneumatic actuator, a hydraulic actuator, a gas actuator, an electric actuator or the like. Advantageously, the actuator  68  desirably may be remotely actuated, for example, from the ground or a control station. 
     The bracket  66  desirably is rigidly fixed to a stationary structure such as a wall (not shown) or a stanchion (not shown). In alternate configurations, the second end of the mechanical linkage  62  may be fixed to a stationary object or may be fixed to a chain, wire or other component to allow for manual manipulation of the actuating mechanism  56 . As schematically shown in  FIG. 4B , when the actuator rod  69  is extended out of the actuator cylinder  68 , the linkage arm  63  is held in a horizontal position and the pivot plate  60  of the latching mechanism  56  does not lift the release member  64 , and thus the latch  50  is closed and will restrain the latch pin  54  and accordingly restrain the associated access panel  28  in the open orientation against the hand rail system  30 . However, as schematically shown in  FIG. 4C , when the actuator rod  69  is retracted into the actuator cylinder  68 , the linkage arm  63  is tilted below a horizontal position and the pivot plate  60  of the latching mechanism  56  lifts the release member  64 , and thus the latch  50  is opened and will release the latch pin  54  and accordingly release the associated access panel  28  from the open orientation against the hand rail system  30  and allow the access panel  28  to move toward the floor portion  22 . 
     At this point in the closing movement operation of the access panel  28 , a damper  44 , as shown in  FIGS. 3A and 3B , acts against the force of gravity and so prevents the heavy access panel  28  from free-falling under the influence of the force of gravity. In one embodiment, as shown in  FIGS. 3A and 3B , a damper  44  extends between the support frame  12  and the access panel  28 . The damper  44  may be a compression only damper, thereby providing damping and/or resistance only when the damper  44  is in compression, for example, when the access panel  28  is transitioning or pivoting downwardly in the vertical direction V between a fully or partially open position and a closed or partially closed position. As shown in  FIGS. 3A and 3B , the damper  44  generally includes a first end  46  that is pivotally coupled to the support frame  12 . As shown in  FIGS. 3A and 3B , a second end  48  of the damper  44  is generally pivotally coupled to the access panel  28 . In one embodiment, the first end  46  of the damper  44  is coupled to the outer portion  16  of the support frame  12 . In one embodiment, the second end  48  of the damper  44  is connected to the access panel  28  proximate to the fixed end portion  36 . 
     The damper  44  controls a closure velocity of the access panel  28  when the access panel  28  is transitioning or pivoting downwardly in the vertical direction V between a fully or partially open position and a closed or partially closed position, thereby reducing or preventing bodily harm to any workers who may be positioned beneath the access panel  28  during an accidental or premature closure of the access panel  28 . In addition or in the alternative, the damper  44  reduces the momentum of the access panel  28  as it closes. As a result, the force of impact of the access panel  28  against the support frame  12  as the access panel returns to the closed position is reduced, thus preventing or reducing damage to the access panel  28  over time, thereby reducing repair/replacement intervals. 
     In particular embodiments, the actuating mechanism  56  may be configured to release all open access panels  28  simultaneously. For example, each release member  64  may be coupled to a common portion of the actuating mechanism  56  so that actuation of the actuating mechanism  56  causes each release member  64  to be engaged simultaneously. In this manner, upon operating the actuating mechanism  56  before egressing onto the floor portion  22 , an operator may be assured that all access panels  28  are disposed in their closed positions. 
       FIG. 5  schematically illustrates a perspective view of an elevating platform  70  including the platform safety enclosure  10  according to one embodiment of the present invention. The platform safety enclosure  10  schematically represented in  FIG. 5  may be coupled to a vertical lift  71  of the elevating platform  70 . In this manner, the platform safety enclosure  10  is carried in the vertical direction V by the vertical lift  70 , thereby raising or lowering the platform safety enclosure  10  in order to access manways and/or other equipment such as valves and fittings that are positioned along a top portion of a container vessel  72  such as a tank trailer, a tanker rail car and/or an isotainer. 
     This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.