Patent Publication Number: US-6698491-B2

Title: Movable wall system with inverted trolley assembly

Description:
BACKGROUND OF THE INVENTION 
     The present invention pertains to operable wall panels movable to partition large rooms into smaller rooms, and, in particular, to an inverted trolley assembly that eliminates binding of the wall panels when they are moved from a wall-forming position to a stacked position. 
     Operable walls or partitions, also known as movable wall panel systems, find useful application in a variety of venues, such as classrooms, offices, convention centers and hospitals. In these venues, the operable walls can be utilized to efficiently divide or compartmentalize an interior space into a multitude of separate, smaller rooms. Operable wall panels are typically connected to trolleys that roll within an overhead track. Travel of the trolleys within the track allows the panels to be moved between a stacked arrangement in a storage location, and a wall-forming, extended arrangement in alignment with the overhead track. 
     One type of movable wall panel system is a continuously-hinged system in which each operable partition is typically hinged to its adjacent partitions. Continuously-hinged wall panel systems are frequently electrically driven between their stacked and extended positions. When arranged in a proper center stacked position, the operable partitions are folded over one another accordion style with each panel or partition being oriented generally transverse to the overhead track. 
     One shortcoming of continuously-hinged operable partitions is that during partition movement, and usually before unfolding, stacked partitions have a tendency to move along the overhead track away from the location at which they are arranged when properly stacked. For instance, when continuously-hinged operable partitions are extended to form a wall, the leading partition, which is connected to an electric motor via a chain, is pulled from its transverse position at the end of a stacked set of partitions and begins to straighten out. Straightening of the leading partition is normally assisted by guide rails flanking the overhead track which engage the partitions. As the leading partition is pulled off, the remaining stacked partitions, still in a substantially stacked arrangement transverse to the track, often begin to move out in the wall extending direction. This movement is undesirable as these stacked partitions can jam at the guide rails and hinder further wall extension. 
     The movement of folded partitions may also be problematic when continuously-hinged operable partitions are stacked. During the stacking process, the trailing partitions which first reach the stacking area are manipulated to break and stack. If these stacked partitions move sideways, they may interfere with the stacking of subsequent partitions and frustrate the stacking process. These problems can be aggravated with non-level tracks as gravity may cause some partitions to drift sideways. 
     An existing assembly or apparatus directed to the problem of movement of stacked panels includes two cables, with loops at each end, and a high tension spring assembly interconnecting the cables. The assembly spring is installed in a recess within the top edge of one partition, and each of the cables is guided through mounted diverters and connected to an adjacent partition. This assembly has several shortcomings. For instance, the assembly is difficult to install, and must be carefully checked and tightened before installation. The separate custom designed components of the assembly are also relatively expensive. Furthermore, the design of the assembly requires that the cables pass within the space normally occupied by the top sweeps, i.e. the space which extends from the room ceiling. The removal of a portion of the top sweeps to accommodate the cables results in a degradation of the acoustical performance of the partition. 
     Another system developed to address this problem is disclosed in U.S. Pat. No. 5,499,671 which is assigned to the assignee of the present invention. This patent discloses an apparatus that includes first and second camming assemblies which are positioned along the track and cooperate with plates extending from the trolley to resist passage of a panel if the panel is transversely positioned relative to the track. The apparatus includes numerous components including pivots, bearings, rollers, and biasing springs, etc. and also requires adjustment of the components. 
     Neither of these approaches addresses the problem of binding of the panels during stacking and extending operations with panels suspended from rigidly centered trolleys. Binding can occur during stacking or unfolding where the panels lock up because adjacent panels, both with trolleys, do not have sufficient play at their leading or trailing edge to extend while pivoting on the trolley. This can be dealt with by removing a trolley from adjacent panel pairs; however, this results in the panel being supported solely by the hinge connections to its adjacent panels which adds unnecessary load to the hinge. 
     Thus, a need remains for an assembly that diminishes the tendency of stacked panels to resist unfolding by moving while remaining in a stacked arrangement and also prevents binding of the panels without the disadvantages of the aforementioned solutions. 
     SUMMARY OF THE INVENTION 
     The present invention provides an inverted trolley assembly for supporting a movable wall panel from within the panel and interconnecting the movable wall panel to a movable wall system. The inverted trolley includes a carrier having first and second ends with a roller assembly attached to each end. The rollers are positioned to engage the underside of the top frame of the movable wall panel when the inverted trolley is installed within the panel. In a preferred embodiment, spacers are included with the roller assembly to center each roller on its axle. The inverted trolley also includes a trolley block attached to the carrier that is connectable to the external trolley of the track and trolley system. 
     In another aspect of the invention, there is provided a movable wall panel with a movable trolley attachment in the form of an inverted trolley for connecting the movable wall panel to an external trolley. The wall panel has a top frame at its upper end. The top frame defines a channel and has a top portion that includes an opening in communication with the channel. In a preferred embodiment, the opening is an elongated slot. The inverted trolley assembly is disposed within the channel in the top frame and is movable within the channel. The trolley attachment assembly is accessible through the elongated slot in the wall panel top frame. In a preferred embodiment, the panel also includes a trolley retainer attached to the base of the channel in the wall panel top frame. The trolley retainer has upstanding portions that limit the range of movement of the trolley attachment assembly. 
     In yet another aspect of the invention, a movable wall system is provided including a track, a plurality of wall panels, each panel having a trolley attachment assembly in the form of an inverted trolley that is movable within a channel in the wall panel top frame, and a second trolley connecting the wall panel and inverted trolley combination to the track for movement of the wall panel along the track. 
     The invention provides a trolley system that eliminates binding of operable wall panels when folded on a single track centerline. 
     The invention further provides a trolley system that allows continuously hinged wall panels to have support trolleys on adjacent panels while operating without binding. 
    
    
     DESCRIPTION OF THE FIGURES 
     FIG. 1 is a diagrammatic perspective view of one embodiment of an operable wall shown being moved from a fully stacked arrangement to an extended wall-forming arrangement, for which the various embodiments of the inverted trolley assembly described herein may be employed. 
     FIG. 2 is a front view of a wall panel cut away to show an inverted trolley assembly according to the present invention. 
     FIG. 3 is a perspective view of an inverted trolley according to one embodiment of the present invention. 
     FIG. 4A is a front elevational view of another embodiment of an inverted trolley according to the present invention. 
     FIG. 4B is a front elevational view of an alternate embodiment of a retainer in accordance with the present invention. 
     FIGS. 4C and 4D are top perspective views of alternate embodiments of an inverted trolley in accordance with the present invention. 
     FIG. 5 is a top view of a removable wall panel for use with an inverted trolley according to the present invention. 
     FIG. 6 is a front elevational view of a wall panel having an inverted trolley of the present invention shown in ghost outline. 
     FIG. 7 is an overhead view of a pair of hinged wall panels demonstrating the operation of the inverted trolley system of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. The inventions includes any alterations and further modifications in the illustrated devices and described methods and further applications of the principles of the invention which would normally occur to one skilled in the art to which the invention relates. 
     Referring now to FIG. 1, there is diagrammatically shown an operable wall, generally designated  10 , which may be equipped with any of the panel anti-stacking systems of the present invention. Operable wall  10  is shown as a paired panel system including three pairs of wall panels suspended from an abstractly shown track  20 . The operable wall typically would include more panels than the shown three pairs, but only such panels are shown as are needed to facilitate illustration and explanation. Operable walls having fewer or even more panel pairs than shown may employ the present invention. 
     Wall panel  11  is linked to panel  12 , panel  13  is linked to panel  14 , and panel  15  is linked to panel  16 , by multiple hinges  18  arranged along the panel height. Paired panels  11  and  12  are shown in a stacked or folded arrangement with the panel width oriented transverse to track  20 . Panels  13  and  14  are shown in a partially unfolded arrangement assumed as the panels are pulled along track  20  from a stacked position toward a wall-forming position. Panels  15  and  16  are shown in an extended or unfolded arrangement as they are moved to a wall-forming location along the length of track  20 . As referenced with respect to panel  14 , each of panels  11 - 16  generally includes a top edge  26 , a bottom edge  28 , a vertical leading edge  30  and a vertical trailing edge  32 , with leading and trailing used throughout the application in reference to the relative position of various components which occurs when the panels are being moved from a stacked position to an extended position. Also with reference to panel  14 , each of the panels also includes side facades  34 ,  36  that are aligned to form exposed wall surfaces in the room areas separated by operable wall  10  when operable wall  10  is fully extended. 
     Each of panels  11 - 16  is suspended from track  20  by trolley  22  abstractly represented in FIG.  1  and shown in more detail in FIG.  2 . The term trolley is used generally herein and is intended to encompass devices of all types that are operably connected to and movable along the track, including wheeled carriages and carriers. The term inverted trolley as used herein is a reference to the subject of the present invention and is used interchangeably with the term trolley attachment assembly which refers to an assembly interconnecting a wall panel to a traditional trolley of a movable wall system that allows relative motion between the wall panel and the traditional trolley. 
     Track  20  spans fixed walls  38  and  40  and is mounted to a support structure (not shown) above the room to be compartmentalized in a well-known fashion. The track parts along which the trolleys  22  ride are located above the ceiling of the room (not shown in FIG.  1 ). Panels  11 - 16  may be moved along the track in any known fashion in wall-stacking and wall-extending directions. 
     Although shown as being employed with a paired panel system, the inverted trolley systems described herein may be adapted for use with different panel systems, including continuously hinged systems and even single panel systems having a single trolley per panel, and with different or non-straight track layouts. 
     FIG. 2 shows a wall panel  16  suspended from the track  20  by trolley  22  and inverted trolley assembly  50  installed within panel  16 . In adapting wall panel  16  for use with inverted trolley assembly  50 , wall panel  16  can include a top frame  26  that can be provided with a channel  44 . The inverted trolley assembly  50  is housed within the top frame channel  44 . Trolley retainer  46  is preferably mounted flush with the bottom of the top frame channel  44 , preferably by welding. The trolley retainer  46  preferably has a base portion  47  and upstanding portions  48  within which the inverted trolley assembly  50  is positioned. 
     Inverted trolley  50  is shown in detail in FIG.  3 . In a preferred embodiment, the inverted trolley assembly includes a carrier  52  that is preferably formed as a channel with a rectangular cross section. The carrier  52  includes a bearing assembly at each end to facilitate movement of the inverted trolley within the top frame channel  44 . In a preferred embodiment, the bearing assembly can be a roller assembly  55 . A bore  59  is provided at each end of carrier  52  through which axles  60  can be received. A roller  56  is mounted on each axle  60 . Spacers  58  can be included to help center the rollers  56  on axles  60 . In one embodiment of the invention, portions of rollers  56  extend through a slot  57  in the carrier  52  so that the rollers  56  can engage the underside of the top portion of the top frame  26  in the manner shown in FIG.  2 . 
     With reference still to FIG. 3, a trolley block  54  is attached to the carrier  52 . In a preferred embodiment, the trolley block is inside the channel of carrier  52 . The trolley block  54  is provided with an attachment portion  62  for connecting the trolley block  54  to the track mounted trolley  22 . Preferably, this attachment is a threaded hole  62  which is sized to receive a pendant bolt  24  as shown in FIG.  2 . The threaded hole  62  in trolley block  54  is coaxially aligned with an access hole  64  in the upper side  63  of the carrier  52 . The carrier upper side  63  can also include holes  66  for mounting the trolley block  54  to the carrier  52 . In a preferred embodiment, the trolley block  54  can be plug welded in place at holes  66 . Alternatively, the trolley block  54  can be drilled, tapped, and held by bolts or screws at hole  66 . 
     An alternative embodiment of an inverted trolley  50 ′ is shown in FIG.  4 A. In this embodiment, the trolley carrier  52 ′ is a flat plate with roller mounting tabs  68  at each end. The tabs include bores for axles  60 ′ on which rollers  56 ′ are mounted. Although shown in FIG. 4A as attached to the underside of carrier  52 ′, a trolley block  54 ′ could also be mounted on the top surface of carrier  52 ′. As depicted in FIG. 4A, attachment of the trolley block  54 ′ to carrier  52 ′ can be by welding or by fasteners through holes  66 ′. Access is provided through hole  64 ′ in carrier  52 ′ for a pendant bolt for attachment to a track mounted trolley. 
     An alternative embodiment of a trolley retainer  76  is shown in FIG.  4 B. In this embodiment, the trolley retainer  76  can include a pair of stops, each preferably having a base portion  77  and upstanding portion  78 . The stops can be attached to either the bottom of the top frame channel  44  or to the underside of the top portion of the top frame  26  preferably by welding. Alternatively, attachment may be accomplished using bolts or screws. 
     Other variations of an inverted trolley are shown if FIGS. 4C and 4D. These variations are similar to a traditional trolley with body portions  154  and  154 ′ adapted for pendant bolt attachment to a track mounted trolley at holes  162  and  162 ′. Wheels  156  and  156 ′ can be mounted on the body portions by any conventional means. Preferably at least four wheels would be used with the inverted trolleys of FIGS. 4C and 4D for stability of the wall panel on the inverted trolleys; however as few as two wheels may be used. 
     Turning now to FIG. 5, a detailed view of the wall panel top frame  26  is shown. Top frame cap  27  includes an opening  70 , within which is centered over a similar opening  71  in the upper side of top frame  26  that provides an access to the top frame channel  44  at the upper end of the wall panel. In a preferred embodiment, openings  70  and  71  can be in the form of elongated slots. Inverted trolley  50  is shown in ghost outline in FIG.  5 . Slot  70  provides access to the inverted trolley  50  and specifically to the threaded hole  62  for attachment of the track mounted trolley to the trolley block, which is hidden in this view. 
     As shown in FIG. 6, with the inverted trolley assembly  50  in place within the wall panel top frame channel, the rollers  56  engage the underside of the top frame channel  26 . Thus, the inverted trolley assembly  50  supports the wall panel from the underside of top frame  26 . Trolley retainer  46  is also shown in ghost outline in FIG.  6 . The range of movement of the inverted trolley assembly  50  can be limited by the span between the upstanding portions  48  of the retainer  46 , or alternatively by the length of slot  71 . Preferably, the length of slots  70  and  71  are sized so that the full range of travel afforded by the trolley retainer  46  is maintained. Alternatively, slots  70  and/or  71  can be used to limit the movement of trolley assembly  50 , in which case, the trolley retainer  46  is used to locate the inverted trolley assembly  50  to attach the pendent bolt  24 . 
     With the inverted trolley installed, the wall panel  16  is also movable relative to the track-mounted trolley  22 . In a preferred embodiment, the relative length of the trolley carrier  52  and the trolley retainer  46  determines the range of motion of the wall panel relative to track trolley  22  which corresponds to the range of movement of the inverted trolley  50  within the wall panel  16 . In a preferred embodiment, the trolley carrier  52  can be about 13 inches in length with a trolley retainer  46  of about 17.5 inches in length and yielding a range of motion of about 4.5 inches. 
     The trolley retainer  46  as well as slots  71  and  70  are preferably offset with respect to the panel centerline toward the panel leading edge. In a preferred embodiment, this offset is about 1.75 inches. This placement of the assembly assists in eliminating the tendency of the panels to bind. The wall panel  16  is thus allowed to float rather than being rigidly attached to the track mounted trolley  22 . The floating action eliminates the binding that often occurs when adjacent panels with rigid center trolley connections are folded on a single track center line. This avoidance of binding is made possible by the panel&#39;s ability to move with respect to the track mounted trolley which provides the panel with limited capability to pivot about the hinged connection while stationary. This action is demonstrated in FIG.  7 . Viewed from above, track  20  is shown with hinged panels  15  and  16  in solid outline and partially folded and with the track mounted trolley at the centerlines of both panels. The panels are shown being further folded in ghost outline as panels  15 ′ and  16 ′ where panel  16 ′ is displaced relative to the track mounted trolley. Panel  15 ′ has pivoted while remaining at the same track location while panel  16 ′ has move closer to panel  15 ′. It is this movement relative to the track mounted trolley that prevents binding of the panels. With the concern for binding alleviated, there is provided the added benefit of allowing continuously hinged panels to have support trolleys in each adjacent panel. 
     The inverted trolley components are preferably of steel construction; however, other materials capable of supporting the weight of the wall panel may be used. 
     Although the invention has been described in terms of a carrier having two wheels, it should be noted that other configurations are also possible. For instance, the inverted trolley could be fitted with four or more wheels. Alternatively, the inverted trolley could be fitted with sliders instead of wheels. 
     While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character. It should be understood that only the preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.