Abstract:
The mobile scaffold vehicle has a motorized base with an upper surface and a first frame member and a second member. The first and second fame members are pivotally mounted near respective opposite ends of the upper surface. The first frame member is movable independently of the second frame member from an inoperative storage position near the upper surface and a generally vertical operative position. The second frame member is movable independently of the first frame member from an inoperative storage position near the upper surface and a generally vertical operative position, so that in their operative positions, the first and second fame members are generally paralel with one another and located near opposite ends of the upper surface. A platform is attachable with the frame members in the operative position and a plurality of anchor arrangements for anchoring the frame members in the operative position, thereby to permit a operator to stand on the platform.

Description:
REFERENCE TO CO-PENDING APPLICATION 
     The subject matter of U.S. provisional application serial No. 60/148,385 filed Aug. 12, 1999 and entitled MOBILE SCAFFOLD VEHICLE is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to the scaffolding. 
     2. Description of the Related Art 
     Scaffolding is widely used as a modular platform to work at high elevations on construction sites, particularly those involving the finishing of the interiors of residential and commercial buildings. Scaffolding is usually a structure having four stationary posts, which may include pads to distribute the weight over a relatively larger floor area. Alternatively, the posts are provided with casters for limited movement of the scaffold over floor surfaces. In the latter case, such movement necessitates that all personnel climb off the scaffold before it is moved, causing significant delays and inconvenience. In this era of time-based job estimating, it would be desirable to have a scaffold which can be moved safely while the personnel can remain on the scaffold. 
     It is therefore an object of the present invention to provide a novel scaffold vehicle. 
     It is a further object of the present invention to provide a motorized scaffold vehicle having improved maneuverability and control. 
     SUMMARY OF THE INVENTION 
     Briefly stated, the present invention involves a mobile scaffold vehicle, comprising at least two frame members pivotally mounted to a motorized base, said base having an upper surface, said frame members movable between an inoperative inclined position adjacent said upper surface and an upright operative position, a platform attachable with said frame members in said operative positions and a plurality of anchor arrangements for anchoring said frame members in said operative position. 
     In another of its aspects, the present invention provides a method of handling scaffolding comprising: 
     providing a motorized base with an upper surface; 
     pivotally mounting at least two frame members to said upper surface; 
     arranging said frame members for movement between an inoperative inclined position adjacent said upper surface and an upright operative position; 
     securing said frame members in said operative position; and 
     positioning a platform on said frame members in said operative positions. 
     In yet another aspect of the present invention, there is provided a mobile scaffold vehicle, comprising a motorized base having an upper surface, at least two frame members movable relative to said base between an inoperative position and an upright operative position, a platform attachable with said frame members in said operative positions and a plurality of anchor arrangements for anchoring said frame members in said operative position. 
     In still another aspect of the present invention, there is provided a mobile scaffold vehicle, comprising a motorized base means having an upper surface, at least two frame member means movable relative to said base between an inoperative position and an upright operative position, a platform means attachable with said frame members in said operative positions and means for anchoring said frame members in said operative position. 
     In yet another aspect of the present invention, there is provided a method of handling scaffolding comprising: 
     a step for providing a motorized base with an upper surface; 
     a step for mounting at least two frame members relative to said upper surface for movement between an inoperative inclined position adjacent said upper surface and an upright operative position; 
     a step for securing said frame members in said operative position; and 
     a step for positioning a platform on said frame members in said operative positions. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Several preferred embodiments of the present invention will be provided, by way of example only, with reference to the appended drawings, wherein: 
     FIG. 1 is a perspective view of a scaffold vehicle in an inoperative position; 
     FIG. 2-1 is a side view of the vehicle of FIG. 1 in an intermediate position; 
     FIG.  2 — 2  is a side view of the vehicle of FIG. 1 in an operative position; 
     FIG. 2 a  is a fragmentary perspective view according to arrow  2   a  of FIG.  2 — 2 ; 
     FIG. 2 b  is a fragmentary perspective view according to arrow  2   b  of FIG.  2 — 2 ; 
     FIG. 2 c  is a fragmentary perspective view according to arrow  2   c  of FIG.  2 — 2 ; 
     FIGS. 3 and 4 are schematic plan views of the vehicle in different orientations; 
     FIGS. 5 a  and  5   b  are fragmentary perspective views of opposite end regions of the vehicle of FIG. 1; 
     FIG. 5 c  is a fragmentary perspective view of a portion of the vehicle illustrated in FIG. 5 a;    
     FIG. 6 is a fragmentary perspective view of yet another portion of the vehicle of FIG. 1; 
     FIG. 7 is a fragmentary perspective view of another scaffold vehicle; 
     FIG. 7 a  is a side view of a the vehicle of FIG. 7; and 
     FIGS. 8 through 13 are schematic views of portions of the vehicle of FIG.  7 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to the figures, particularly FIG.  2 — 2 , there is provided a mobile scaffold vehicle  10  comprising a frame including a pair of end frame assemblies  12 ,  14 , a pair of side frame assemblies  16  and an undercarriage  20  to support the end frame assemblies. The undercarriage  20  includes a wheel assembly  22  and a motor unit  24  (see FIG. 5) for delivering power to the wheel assembly. 
     The undercarriage  20  also includes a base  26 . As will be described, each of the end frame assemblies  12 ,  14  is pivotally connected with the base  26 , for movement between a storage position, as shown in FIG. 1, and an upright operative position, as shown in FIG.  2 — 2 . The base  26  includes a chassis (as shown in FIGS. 5 a,    5   b ), formed by a number of structural members, one shown at  27 , to provide a mounting location for a number of outer panel members, one shown at  28  in FIG. 1, and providing an inner cavity for a steering linkage, a number of batteries and control circuitry as will be described. 
     Referring to FIGS.  1  and  2 — 2 , each of the end frame assemblies  12 ,  14  has a pair of uprights  12   a ,  14   a  with at least one lateral member  12   b ,  14   b  extending there between for supporting a platform  32 . The lateral members  12   b  are positioned so as to be at equal elevation to the other lateral members  14   b , so that the platform can be at any one of a number of elevations depending on the job at hand. The platform has a pair of hook members  34  on each end thereof allowing the platform to rest atop a given pair of lateral members  12   b ,  14   b.    
     Each of the end frame assembles has a lower portion  36  which is pivotally attached to an upper portion  38  about a hinge assembly  40 . Pivot flanges  12   c ,  14   c  are also fixed to the lower end of the respective uprights  12   a ,  14   a  and is pivotally connected to the base  26 . As seen in FIG. 1, the pivot flanges  14   c  are slightly longer than the pivot flanges  12   c , so that, in the storage position, the end frame assembly  14  is offset vertically relative to the end frame assembly  12 , to allow for their nesting. Furthermore, the pivot flanges are of sufficient length to form a passageway  42  between the end frame assembly  12  and the undercarriage in order to store therein the platform  32  and the side frame assemblies  16 . 
     In the operative position, the upper end of the end frame assemblies are joined by a pair of struts  44 , each having a pair of end portions  44   a  to engage an inner passage in the corresponding upper portion  38  as shown in FIG. 2 b . Each of the side frame assemblies  16  includes a pair of scissored struts  46 , whose ends are each provided with a passage to receive an anchor pin  47  to anchor each strut to a corresponding portion of the end frame assembly, as shown in FIG. 2 a . Thus, the frame assemblies  12 ,  14 , the struts  44  and the side frame assemblies form a work space above the platform, shown generally at  49 . 
     Referring to FIGS. 5 a  and  5   b , the wheel assembly  22  includes a plurality of wheels  49 , one of which is a driving wheel  49   a  to receive power from the motor unit  24 . The wheel assembly also includes a suspension arrangement  52  for mounting each of the wheels for rotation about a corresponding steering axis. The suspension arrangement includes a pair of frame members  54  extending outwardly from the base  26  with a gap therebetween to receive a wheel hub support  54   a . The frame members  54  have coaxial passages to receive a swivel pin  56 , itself extending through the wheel hub support  54   a . Referring to FIGS. 5 a  and  5   c,  the motor unit preferably includes a motor  60 , for example an electric, hydraulic or pneumatic motor, which is mounted on a transmission unit  60   a  which in turn has a output drive  60   b  to be fixed to the drive wheel  49   a.  The transmission unit is pivotally mounted between a lower support flange  60   c  extending outwardly from the vehicle chassis and an upper support block  60   d  which is fixed to the upper region of the chassis. Both the upper and lower support blocks have coaxial passages to receive a pivot shaft  60   e,  itself extending through a passage  60   f  in the transmission unit  60   a.    
     Referring to FIG. 3, the wheel assembly  20  also includes a linear actuator unit, for example electric, hydraulic or pneumatic, shown schematically at  62  and a steering linkage  64  joining the linear actuator unit with the wheels. Thus, the wheel assembly  20  allows for four-wheel steering. The linkage includes longitudinal spans  64   a  joining a selected wheel to a toggle  66 , itself centrally pivoted at  66   a  and driven by the linear actuator  62 . 
     Referring to FIGS. 6 and 7, a controller unit  70  is provided to control the motor unit  24 . The controller unit  70  has a portable housing  70   a  joined to the motor and steering mechanisms by a cord  72 . A hook  74  or similar attachment is provided on the controller housing so that the controller unit can be hooked to a convenient location above the platform. In this manner, the controller unit can be positioned at one of a number of mounting locations on the frame assembly. Thus, the controller unit is of particular value because the user is capable of maneuvering the assembly while being on its working surface, as will be described. 
     Referring to FIG. 2 c , the frame further includes a plurality (in this case four) of outrigger members  80  operable for laterally stabilizing the vehicle. Each outrigger member includes a caster wheel  82  positioned on a arm  84 , the latter of which is slidably engaged in a corresponding sleeve  86  positioned on the lower portion of the chassis. There are, in this particular case, four sleeves  86  on the chassis to receive four outrigger members  80 , although more or less outrigger members may be used, as deemed appropriate. 
     The vehicle  10  is compact, allowing for transport in a conventional panel truck, partly because the end frame assemblies are pivotally connected with the base, each between a storage position and an upright position. Furthermore, the end frame assemblies are arranged so as to nest with one another in the storage position. 
     To prepare the vehicle  10  for operation, it is first deployed from its storage position, which involves removing the struts  44 , the platform  32  and the side frame assemblies  16  from atop the undercarriage. The end frame assemblies  12 ,  14  are then hinged upwardly from their nested horizontal position and the struts  44  are fastened with the upper portions  38 . The side frame assemblies  16  are then coupled to the corresponding anchor pins and the platform  32  is then positioned on one pair of lateral support members, according to the height at which the user wishes to work. The user then hooks the controller unit at a convenient location within comfortable reach from the platform  32 . 
     The user can then install the outrigger members in their corresponding sleeves to complete the assembly. It may be that, in some cases, the outrigger members need not be used, depending on the relative dimensions of the vehicle. For example, the wider the undercarriage, the greater stability it will have and therefore reduce the need for the outrigger members. Similarly, the higher the elevation of the platform, the greater the need for the outrigger members. 
     The scaffold vehicle is shown in another variation at  100  in FIGS. 7 and 7 a , having a pair of frame assemblies  102 ,  104 . Each has a lower portion  102   a ,  104   a , an intermediate portion  102   b ,  104   b  and an upper portion  102   c ,  104   c  which are interconnected respectively by hinges  106 ,  108 . In this case, the end frame assemblies are operable with the upper portions  102   c ,  104   c  between a first relatively low position as shown in dashed lines in FIG. 7 a , and a second relatively high or upright position as shown in solid lines in FIG.  7 . 
     The vehicle variation  100  is further provided with an interlock circuit to control the operation of the vehicle when the upper portions  102   c ,  104   c  are in their upright position and only when the outrigger members are in place. This is done to ensure that vehicle is not operated in a potentially unstable manner. The interlock circuit operates in a first phase to detect the position of the frame and in a second phase to disable the motor unit when the frame is in the second position without the outrigger members in their operative position. 
     The circuit includes a number of magnetic proximity switches to form, collectively, a closed circuit when the upper segments and the outrigger members are in their proper positions to ensure stable operation of the vehicle. As shown in FIG. 3, switches  110   a - 110   d  are located within the sleeves  86  and are arranged to close when the corresponding outrigger members are properly installed, thereby forming a first closed circuit. Two switches are located on each end frame assembly, as shown in FIG. 7 a , at  112   a ,  112   b , in order to close when the upper portions are in their folded-up position, thereby forming a second closed circuit. Also provided is a monitoring system to monitor the closed circuit conditions of the proximity switches and to control accordingly, the power from a power source, in this case a battery pack, to the motor and steering assembly. Should, for any reason, one of the two circuits be opened, as would occur if any one of the switches themselves is opened, the monitoring system detects the open position and blocks further power feed from the power source. 
     FIGS. 8 through 13 show the control circuitry associated with the controller in more detail. A battery pack  120  is joined to a forward-reverse motor  60  and a left-right motor  62   a  driving the linear actuator  62 . The control of the forward-reverse motor is achieved by a motor drive card, available from IPC Automation, as shown at  122 . The drive card has inputs shown at  122   a ,  122   b  and  122   c  which receive the  24  VDC supply from the battery pack  120  and inputs shown at  122   d,    122   e  and  122   f  which provide for a control of the function of the forward-reverse motor  60 , the latter being attached at the drive outputs  122   g  and  122   h.    
     Referring to FIG. 11, the motor&#39;s speed and direction is controlled by circuitry, shown generally at  130 , which adjusts the resistance across the inputs  122   d,    122   e  and  122   f,  by the action of relays  132 ,  134  and the polarity between the inputs  122   d  and  122   e,  the latter through the actions of relay switches  136   a,    136   b.    
     Referring to FIG. 12, the voltage is supplied to the left-right motor  62   a  by way of two sets of relays  138   a,    138   b  and  139   a,    139   b.    
     Referring to FIG. 10, the control circuitry includes an emergency stop switch  140 , a battery charging-activated system interrupt switch  142  and a key switch  144 , as well as two other safely switches  180  and  182  as will be described, all of which have the ability to shut down the supply voltage to the control circuitry under different situations, that is under an emergency when the operator must stop the device, when the battery charger is plugged in to a wall socket, when the device is simply shut down after a job and finally when the frame members and outriggers are not in their proper position when in use. 
     The control circuitry also includes forward and reverse switches  166  and  168  which control relays  132  and  136   a,    136   b  respectively, a “hi speed” switch  170  which controls relay  134  and a combination of left, right and enable switches  172 ,  174  and  176  which control relays  138   a ,  138   b  and  139   a,    139   b.    
     Referring to FIG. 10, for the device  10  employing outriggers, there is provided a switch shown at  180  which is closed when the series circuit of the magnetic reed switches  112   a ,  112   b , on each upper frame portions is also closed. In this manner, if either of the upper frame portions are not in their fully upright position, then the series circuit is broken and as a result opening the supply line  200 , or otherwise shutting down the device. In addition, the switch  182  is also closed when the series circuit of four magnetic reed switches  110   a  to  110   d  at the sleeves are closed indicating that the outriggers are properly in place. Should any one of the outriggers not be in a proper position, the series circuit is broken thereby opening the supply line  200 , similarly to shut down the device. 
     While the end frame assemblies on vehicle  10  and its variation  100  are pivoted to the base, the pivot may be made releasable, if desired, so that the end frame assemblies may be stored in another arrangement. The end frame assemblies need not necessarily be pivoted to the base. Instead, they may be provided with a pair of mating upright mounting slots on the upper surface or on the end or sides of the base to receive the end frame assemblies, or positioned on the base in some other suitable manner. While the end frame assemblies are stored adjacent the upper surfaced, they may, instead, be stored in a cavity below an upper surface, if desired. Although electric motors and actuators are used, their hydraulic and pneumatic counterparts may be preferable in some cases.