Primary Examiner Dennis L. Taylor Attorney, Agent, or Firm-Biebel, French & Bugg [57] ABSTRACT A system of floor supported panels or partitions inatt 11 1 1111 3,M,33
Baggy May M, 1974 MOVABLE PANEL SYSTEM cludes a series of individual rigid panels which are Inventor! Earl 83), Richmond, I d pported from movement between ceiling and floor tracks, while the weights of the panels are supported Assigneei American Standard -1 New York, on the floor tracks. A unique stacking system is pro- N.Y. vided which permits the panels to be stacked in parallel side-by-side relation without the use of special [22] Ffled' Sept 1972 stacking tracks. A combined panel pivot and lock is [2]] Appl. No.2 286,562 provided by the upper trail shoe on each panel in the ceiling track, while the lower track shoe permits the 52 us. c1 49/127, 49/404 49/425 Panel to 9. a imluding the upper 51 int. 131 EOS d 15/58 while resstmg' kngtudmal [58] Field of Search 49/127 125 404, 409, Panel the track- A lwer leadmg espe' 166/206 199 cially adapted to leave the floor track when the panel is swung into its storage position essentially normal to [56] References Cited the tracks. As each panel is pivoted, as described, its upper trail shoe locks with the corresponding shoe of UNITED STATES PATENTS 1 I the preceding panel. in the case of the first panel, its
2,976,582 Rosenthal hoe locks a fixed dummy hoe in the ceiling 3,060,521 10/1962 Grew 49/127 X track. In this manner, the upper pivotal end of each panel is positively locked during the times that the 3:654:732 4/1972 Schacht .2: I: 49/127 panel is being moved into storage position and while it is in storage.
5 Claims, 17 Drawing Figures 1 MOVABLE PANEL SYSTEM BACKGROUND OF THE INVENTION This invention relates to movable and stackable wall closure assemblies and more particularly to an assembly of individual panels which are guided between floor and ceiling tracks and in which the weights of the panels are, supported on the floor tracks.
It is often desirable to install a movable space divider system into pre-existing structures, some of which may be older buildings. However, it is often not practical to install the conventional overhead supported and suspended system of movable panels, and this may be due to the fact that such installation usually requires costly and extensive modifications of the room ceiling including the incorporation of additional support structure to carry the weight'of the panels. A further deterent to the installation of a space divider system in an old building may be the lack of trueness between the ceiling and the floor, such as due to the settling of the structure. In such cases, it is desirable to support the weights of the panels directly on a floor track while providing a ceiling track primarily for panel guidance. Such ceiling tracks usually may be secured directly to the existing ceiling structure since they do not carry the weight of the panels.
Another problem which is frequently encountered when installing movable wall panel systems into existing buildings is that of panel storage. Hidden wall storage or parallel track systemsadd to the cost of installation, and may not be practical without extensive change to the existing structure.
SUMMARY OF THE INVENTION This invention is directed to an improved floorsupported system of panels which is particularly adapted for use in existing structures but which may also be used with advantage in new buildings as well. A novel panel stacking arrangement is provided by which the panels may be easily stack in a parallel side-by-side relationadjacent one of the room walls.
The panel system includes a supporting floor track and a guiding ceiling track. The trailing edges of the panels are guided in the ceiling track, and the guiding arrangement includes a'special locking and holding puck which permits the leading edges of the panels to be swung transversely from a condition aligned with the track to a storage position essentially normal to the track. The ceiling guide thus includes alocking feature which causes the associated panel to be locked or braked in longitudinal relation to the track during movement of the panel into the storage position and during storage, while defining an upper joint or pivot about which the panel may turn.
The bottom of each panel is supported by guide means at both its leading and trailing ends. The leading end floor guide is adapted to leave or exit from the floor track at a preselected storage position while a trailing guide provides a pivot point in vertical alignment with the pivot provided by the ceiling guide. The initial movement of the panel from its track aligned position to its storage position operates the mechanism of a the guide or puck at the upper trailing edge tolock the trailing edge against longitudinal movement along the track, thus permitting the panel to be pivoted on an axis extending vertically through the upper and lower guides.
In one embodiment of the invention, the trailing end carrier in the floor track has wheels which remain in the track while a threaded support post provides pivotal support for the panel during movement into and out of the stacking position. The leading end floor guide includes a ball which is adapted to leave the floor track when the panel is moved toward storage. The upper locking puck includes a finger which engages with a cooperating retainer slot in the adjacent puck of the preceding panel to lock the panel top against move ment along the track while permitting pivotal move ment of the panel. In the case of the trailing panel itself, its locking puck engages with a fixed dummy puck in the ceiling track.
In another embodiment of the invention, the lower trailing edge carrier assembly includes a specially constructed stacking puckwhich slides with the carrier along the floor track but which provides a fixed support platform for the carrier during stacking movement. A modified leading edge carrier assembly employs track engaging wheels and a center guide, and is movable transversely out of the floor track through an access opening formed in the side of the track when the panel is in a preselected storage position.
An important object of the invention is to provide a stackable, floor-supported system of panels as outlined above in which the trailing edges of the panels at the top and at the bottom are locked with respect to movement within the track while providing for pivotal panel support, such locking taking effect automatically in response to the transverse swinging movement of the panel leading edge from its track-aligning position toward its storage position.
Another object of the invention is the provision of a low-cost floor-supported stackable assembly of panels particularly adapted for use in dividing rooms in existing buildings and structures.
A further object of the invention is to provide a system of stackable floor-supported-panels in which the individual panels are pivotally mounted with respect to an overhead and a floor track for stacking in side-by-- side relation essentially at one longitudinal side of the tracks.
A still further object of the invention is the provision in a panel system as outlined above of an automatically locking guide which fixes the top of the panel longitudinally with respect to the track during storing movement and while the panel isin its storage position.
Another object is the provision for side-by-side storage in a system of individual panels without requiring the use of parallel storage tracks in either the ceiling or the floor.
These and other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a side view of a panel system of this invention;
FIG. 2 is a somewhat diagrammatic top elevation looking generally along the line 2-2 of FIG. 1;
FIG. 3 is an enlarged vertical section, partially broken away, of one of the panels;
FIG. 4 is a transverse vertical section, partially broken away, taken along the line 4-4 of FIG. 3;
FIG. 5 is a vertical fragmentary detail showing the leading edge floor guide taken along the line 5-5 of FIG. 3;
FIG. 6 is a view similar to FIG. 5 showing the leading edge of the panel being moved to a storage position;
FIG. 7 is a plan view showing the trailing end locking pucks ofa pair of adjacent panels and looking along the line 7-7 of FIG. 3;
FIG. 8 shows the parts illustrated in FIG. 7 after one panel has been moved up against the preceding panel and the stacking movement is commenced;
FIG. 9 is a view similar to FIG. 2 illustrating a modified form of the invention;
FIG. 10 is a vertical fragmentary section of one of the panels similar to FIG. 3, showing further details of the modification;
FIG. 11 is a vertical section showing the modified leading end floor guide taken along the line 11-11 of FIG. 10;
FIG. 12 shows the floor guide in position to be moved to storage position,
FIG. 13 is an enlarged vertical section, partially broken away, along the line 13-13 of FIG. 10;
FIG. 14 is a view of the trailing end floor guide showing the manner in which it is pivotally supported on the stacking puck when the panel ismoved to its storage position;
FIG. 15 is a vertical section taken along the line 15-15 of FIG. 13 showing the manner in which the stacking puck is guided and moved along the track with the trailing end trolley;
FIG. 16 is a plan view of the floor track showing the access slots through which the leading end trolley moves for storage; and
FIG. 17 is a plan view of the stacking and locking puck at the trailing end of the panel looking along the like 17-17 of FIG. 10.
DESCRIPTION OF PREFERRED EMBODIMENTS In the description which follows, the terms lead" and leading" and the terms trail and trailing are used in conventional sense to refer to the positions of the edges or ends of the panels as they are moved from the stacked position as shown in FIG. 2 to their coplanar or wall closing position as shown in FIG. 1. Thus, the lead or leading edge of the panel will always be in reference to panel movement from the stacked position to the operative position.
The system of floor-supported panels is illustrated in elevation in FIG. 1 as comprising a series of individual rigid panels 10 and an expanding" panel 11 all of which are supported between a ceiling track 12 and a parallel floor track 14. The panels 10 and 11 are movable between the coplanar room dividing position as shown in FIG. 1 to a generally parallel side-by-side storage position as shown by the position of four of the live panels in FIG. 2. The internal structure of the individual panels 10 is not important to an understanding of the present invention, but these panels are preferably constructed according to the teachings of the copending application of Daggy, Ser. No. 243,272, filed Apr. 12, 1972, and assigned to the same assignee as this invention. The expanding panel 11 may be made as shown in my copending application Ser. No. 243,273, filed Apr. 12, I972.
The weights of the panels 10 and 11 are supported directly on the floor track 14, and for this purpose each panel includes identical lead shoes or trolleys 15 and identical trail shoes or trolleys 16. The upper edges of the panels are supported and guided by the ceiling track 12 and each panel is provided with a single upper trail shoe 20 received within the ceiling track. The lower shoes 15 and 16 are not necessarily sliders or shoes in the strict sense of the term, but preferably are actually trolley-like arrangements to provide for the rolling engagement with and support on the floor track 14 to permit movement of the individual panel with a minimum of friction.
The ceiling track 12 is shown in cross section in FIG. 4, and as previously mentioned, may be suitably connected or attached to an existing ceiling structure. The arrangement shown in FIG. 4 includes a pair of soffits or trim boards 21 which conceal the sides of an inverted channel-shaped track. The upper panel shoes 20 are adapted to be slidably inserted within the track 12 to provide guidance for the upper edges of the panels, while lower trolleys or shoes 15 and 16 actually support the weight of the panels on the floor track 14 also shown in cross section in FIG. 4. The floor track 14 may thus include a bottom upwardly-opening channel portion 25, a pair of upwardly-facing beveled sides 26 and 27 and an outwardly and somewhat downwardlydiverging floor-seal engaging side portions 28 and 29.
As shown in FIGS. 3 and 4, the panels 10 and 11 are formed with upper transverse channel frame members 30 and corresponding lower transverse channel frame members 32 as fully described in Ser. No. 243,272 which respectively support the upper and lower trolleys or shoes. Additionally, the upper and lower channels provide means for supporting multi-fingered sweep seals 33, again as more fully described in copending application Ser. No. 243,272.
In the embodiment of'FIGS. 1-8, the lower trailing trolley consists of a single wheel 40 which is received within the channel portion 25 of the track 14 as shown in FIG. 4. The wheel 40 is supported on a bifurcated wheel support body 42 which, in turn, is threaded for pivotal movement within a supporting nut 44 mounted on a corner brace 45.
An upper corner brace 45 rigidly supports a locking arm support shaft which is operatively associated with the upper shoe 20. The arm 50 is rigidly mounted with respect to the panel and is in alignment with the vertical center line or the turning axis of the corresponding lower trailing edge trolley 16. The details of the upper shoe 20 may best be seen by reference to FIGS. 7 and 8, which are plan views with the track 12 removed for the convenience of illustration.
The upper shoe 20 may be made of metal or molded plastic material, such as nylon, and has an elongated body portion 52 which is adapted to be received within the track 12 for sliding and guiding movement therein. The shoe 20 is provided with a pivotally-mounted latch portion 55 located adjacent the trailing edge of the body portion 52. The locking arm support shaft 50 is directly connected to the latch portion 55, and in effect, the latch portion 55 consists of a locking arm 57 and depending locking finger 58, the finger 58 being best shown in FIG. 3. The opposite or leading end of body 52 is formed with an arcuate slot 60, as shown in FIGS. 7 and 8, said slot being adapted to receive therein the finger 58 of an adjacent shoe 20. The slot 60 is formed with a longitudinally-aligned lead-in portion 60A to receive the pin 58 for the purpose which will be described hereinafter.
The leading edge lower support trolley is illustrated in FIGS. 3 and 5 as including a ball carrier '65 and a ball 66 thereon, the ball being adapted to roll along the beveled sides 26 and 27 of the floor track 1 1. The carrier 65 is formed with a threaded bolt 67 receivedwithin a nut 68 mounted on one of the braces 45 adjacent the lower leading edge of the panels 11. The nut 68 is provided with a set screw 69 by means of which the height of the ball 66 may be adjusted with respect to the floor track, for leveling the panel. The trailing edge wheel 40 may be similarly adjusted in height by means of rotating the roller support 42 within its corresponding nut 44, to provide initial adjustment in height of the sweep seals 33 with respect to the sides 28 and 29 of the track. However, no lock or set screw arrangement is provided for the trolley 16 as the threaded support also provides a pivotal support for the associated panel.
For the purpose of providing stacking support for the expanding panel 11, a partial or dummy shoe A is provided at the extreme end of the track, at the stacking end, as shown in FIGS. 1 and 2 and as shown partially broken away in FIG. 7. The partial shoe 20A is provided with a slot 60 and is fixed to the track 12, and is adapted to be engaged by the locking finger of the locking shoe 20 associated with the expanding panel 11.
When it is desired to store the panels 10 and 11, the operating handle70 of the expanding panel 11 is retracted, bringing in partially the panel section 11A and thus releasing the edge-to-edge-sealing force which had been applied to the assembly of panels in the manner disclosed in copending application Ser. No. 243,273. The panel llis then moved to the right, as viewed in FIG. 1, so-that the locking finger 58 engages the slot 60A. At this point, the leading edge of the panel 11 is grasped moving it sideways and lifting the ball 66 out of the track 14. For this purpose, the track 14 may be provided'with a lateral extension portion 72, as shown in-FIG. 6, portion 72 being at least equal to the width of the panel, to provide support for the lower leading edge of the panel during the initial movement thereof from the coplanar position to the parallel stacked position and until the finger 58 has an opportunity to engage with the adjacent slot 60. Thereafter, the top of the panel is pivotally supported about the shaft 50, and longitudinal movement along the track is positively prevented by reason of the engagement of the locking arm 57 with the adjacent puck 20 or 20A. The lower roller or wheel 40, in this embodiment, remains within the channel'portion 25, pivotal movement being accomplished by the turning of the panel on the threaded portion of the leading edge trolley.
Once the panel 11A has been moved to the position .shown in FIG. 2 in which it is normal to the tracks, the
adjacent panel 10 may be moved into position as shown in FIG. 7 until its associated locking finger 58 enters the lead-in slot 60A. At this time, the panel may similarly be grasped to effect turning movement of the entire panel concurrently with the track-exiting movement of the ball 66, again as illustrated by the broken lines of FIG. 6. The track portion 72 again provides temporary support of the panels until such time as the finger 58 has entered the arcuate slot 60 of the next adjacent body 52. Thereafter, panel 10 is similarly locked and may be swung above the pivot axis defined by the upper and lower trailing edge shoes.
Preferably, some provision is made for temporarily locking the wheel 40 in a pre-selected track position, and for this purpose, the roller channel portion 25 of the track 14 may be provided with a series of slight recesses or detents 75, as shown in FIG. 3, there being one such detent for each position of the associated wheel 40 in the stacked position of the panels. The panels accordingly are stacked in parallel side-by-side relation as shown in FIG. 2. When it is desired to return the panels to an operative, position, they are taken oneby-one in reverse order from the stacked position back into the coplanar position at which point they may be slid along the track as illustrated by the panel 10A in FIG. 2. In the coplanar position, the finger 58 is returned to the entrance portion 60A of the slot 60 and thus the associated panel may be readily moved longitudinally of the track.
Theembodiment of FIGS. 9-17 operates on the same principles as that of the embodiment of FIGS. 1-8, and the internal structure of the individual panels 10 and 11 is the same as that previously described. However, modified forms of the leading and trailing edge guides or shoes are disclosed and these forms may be preferred, in some instances, .to those previously described.
Functionally, the modification of the top guide and locking puck is not changed substantially from that of the puck 20 previously described. A one-piece locking arm 102 is employed with an integral depending finger 1113, again attached to the locking arm support shaft 50 for movement with the shaft as the panel is pivoted, as previously described. The leading edge of the puck 100 is provided with a lead-in portion 104 and an arcuate keeper 105, through and behind which the finger 103 moves with locking pivotal movement of the associated panel, as shown in FIG. 17. The lower surface of the puck 100 is provided with depending buttons 108, as shown in FIG. 13, upon which the puck rides within the track 12. i
A modified form of the floor track is illustrated generally at in FIG. 13. The track includes a lower aluminum extrusion 112 and a pair of upper extrusions 114, the upper extrusions being secured with the lower extrusion directly to the flooring by means of flathead screws 115. Stainless steel joiner strips 116 are snapped in place over the left and right portions of the track and form therebetween a longitudinal slot 117. A pair of beveled surfaces 118 and 119 lead into the slot 117.
A modified form of trailing edge trolley 120 is adapted to be used with the track 110. The trolley includes a depending wheel-supporting body 121 and a pair of rollers or wheels 122 and 123 mounted thereon, the rollers being adapted to ride on the flat upper surfaces of the stainless steel strips 116 as shown in FIGS. 11 and 12. The wheeled trolley 120 is further provided with a surrounding dolly illustrated generally at 125 in FIGS. 1341.5. The dolly has a central upwardly extends ing boss 126 which is keyed within a lower opening formed in the shaft 121. The dolly 125 may be formed of plastic material and has a pair of fore and aft-depending guide portions 127, proportioned to be received within the track slot 117, and provides the means for guiding the trolley 120 as it moves along the track.
The body of the dolly 125 is provided with openings 128 (FIG. through which the trolley wheels 122 and 123 rotate in engagement with the track. The dolly is further provided with spring-loaded glide means on the body at the four corners thereof, the glide means being illustrated generally at 130 in FIGS. 13 and 14. The glides include plastic buttons 132 having stems 133 received through the dolly. Wafer-type springs 135 are positioned between the head of the button and the body of the dolly and normally lift the dolly in slightly elevated relation to the floor track in the normal sliding movement of the dolly.
The trolley body 121 and the associated wheels 122 and 123 are not pivotally mounted but are fixed in relation to the panels, as by the set screw 133 in FIG. 15. When the the associated panel is pivoted from its position in alignment in the tracks to a stacked position as shown in FIG. 9, the trolley wheels 122 and 123 are caused to ride up out of the slots or openings 128 in the dolly 125, as shown in FIG. 14, and rest on top of the dolly. When the weight of the associated panel is thus transferred from the track to the dolly, the buttons 132 are depressed, thereby transmitting the .panel weight directly to the dolly 125 and from the dolly to the track. This is accompanied by a slight elevating movement of the panel during rotation. The accompanying lifting movement of the panel as the dolly wheels ride up on the dolly into the position shown in FIG. 14 provides greater clearance between the bottom of the panel and the floor, and assists the panel in moving to stored position over a carpeted floor. The dolly 125 also provides a stable platform for the trailing edge of the panel to rest on during rotation and while in the stored position.
with the pair of track-engaging wheels 154 and 155 on the upper surfaces of the track. The lower end of the trolley is provided with a longitudinally extending guide portion 156 which is partially received within the slot 117 defined by the track sections, and serves to guide the trolley 150 for movement along the track, but does not form or provide any weight-supporting function itself. The track, at the stacking region, is provided with a series of interruptions or openings 160 as shown in FIG. 9 and again in FIG. 16. The openings 160 are positioned so that they are in alignment with one of the trolleys 150 when the panels are moved to their stacking position, and provides means by which the entire trolley 150, including the guide portion 156, may be moved transversely out of and into the floor track 110 for stacking purposes.
The embodiment of FIGS. 9-17, particularly in the arrangement of the leading and trailing edge floor trolleys, provide certain advantages over those which have been described in connection with FIGS. 1 and 2. The dolly associated with the trailing edge trolley 120 provides guidance for the dolly as it moves along the track, and at the same time, provides a stable platform about which the dolly wheels 122 and 123 may move during stacking, as shown in FIG. 14. Thus, the dolly provides a stacking platform which resists longitudinal sliding movement of the bottom edges of the panels during stacking and unstacking. The leading trolley is similarly guided by the portion 166 along the track, and the track interruptions permit ease of movement into and out of the stacked position as illustrated in FIG. 9.
It will accordingly be seen that the invention provides a unique arrangement of rigid panels which is primarily floor-supported and which is adapted for installation into existing structures with a minimum of modification or change to the structure. Since the ceiling tracks 112 do not carry the weight of the panels, they may be readily attached to existing structures. The individual panels may be easily leveled by means of vertical adjustments and the leading and trailing guide at the lower ends of the panel. The floor track may be mounted directly onto existing floor structure. Further, stacking of the panels when not in use is accomplished with a minimum of accessory installation required, specifically eliminating the need for special parallel stacking tracks as are common in parallel stacking arrangements. Accordingly, in the stacked position, the panels are exclusively supported between their trailing upper and lower edges on the stacking pucks and the stacking trolleys as described herein.
While the forms of apparatus herein described consitiute preferred embodiments of the invention, it is to be understood that the invention is not limited to these precise forms and that changes may be made therein without departing from the scope of the invention.
What is claimed is:
1. A room divider system comprising a floor track and a ceiling track extending transversely across a room opening, a plurality of individual panels extending between said track means on the bottom of each said panel defining leading and trailing edge weightsupporting roller means engaging said floor track, trailing edge panel guide means on each said panel received in said ceiling track, said guide means and said trailing edge roller means providing for pivotal movement of the associated said panel about a vertical axis through said guide means and said trailing edge roller means into a stacked position normal to said tracks, locking means associated with said guide means for supporting said panel against movement in said ceiling track in response to said pivotal movement, means associated with said trailing edge roller means and responsive to said pivotal movement for locking engagement with said floor track, said trailing edge roller means comprising a wheeled trolley and said associated means comprises a dolly having a body received about said trolley and movable therewith along said floor track, means in said body defining openings through which said trolley wheels normally engage said floor track, spring loaded glide means in said body normally supporting said dolly in slightly elevated relation to said floor track, said trolley being rotated with respect to said dolly body in response to said panel pivotal movement to lift said trolley wheels out of said openings and onto said body thereby transmitting panel weight directly to said dolly, said glide means being adapted to retract under said application of panel weight to said dolly for pressing said body onto said floor track thereby effecting said locking engagement.
2. In a floor supported partition including a series of individual panels supported between a ceiling track and a parallel floor track and movable between a coplanar room dividing position and a parallel side-by-side storage position, the improvement in panel stacking system comprising each said panel having an upper trail shoe received in Said ceiling track, a lower trail shoe and a lower lead shoe engageable with said floor track, means in said floor track defining an opening at one side thereof and a support platform adjacent said opening, said lower lead shoe being movable transversely out of said floor track through said opening and on to said support platform with swinging movement of the associated said panel about a vertical axis including said trail shoes, panel locking means associated with said upper shoe comprises a'body portion aligned in said ceiling track and a latch portion pivotally mounted adjacent one end of said body portion, pendant means connecting said latch portion for pivotal movement in response to said panel storing movement, slot means defined adjacent the opposite end of said body portion, said latch portion being proportioned to move into said slot means of an adjacent said trail shoe of an adjacent said panel to effect said upper trail shoe locking, said latch portion proportioned to move into said slot means prior to the disengagement of said lower lead shoe with said support platform providing temporary support for said panel for movement into said storage position.
3, The system of claim 2 further comprising means on said lower trail shoes responsive to movement of said panels into. said storage position for supporting said lower trail shoes against longitudinal movement on said floor track.
4. The system of claim 3 in which said lower trail shoes each comprise a trolley having a pair of wheels on said floor track, a dolly having a body received about said trolley and movable therewith along said floor track, means in said body defining openings through which said trolley wheels normally engage said floor track, said trolley being connected to said panel for rotation onto said dolly body in response to said panel pivotal'moveme'nt, lifting said trolley wheels out of said openings and onto said body thereby transmitting panel weight directly to said dolly,'and slightly lifting said panel with respect to said track pressing said body onto said floor track to prevent sliding movement and providing clearance of said lead shoe for movement over carpet and the like.
5. In a room divider system in which a plurality of individual panels extend between a floor track and a ceiling track and in which each panel is provided with lower leading and trailing edge trolleys which support the weight of the panels and with a trailing edge guide in the ceiling track, and in which the individual panels are movable into parallel side-by-side storage condition by pivotal movement about a vertical axis at the trailing edges thereof, the improvement comprising means in said ceiling track guides responsive to storage movement of said panels for locking the upper trailing panel edges against movement in said ceiling track'when said panels are moved toward their storage position, and means associated with each said trailing edge trolley for securing the associated lower trailing edge-with respect to the floor track including a dolly received about said lower trailing edge trolley and having guide means in said floor track and movable along said floor track with said trolley, means in said dolly defining openings through which said trailing edge trolley wheels normally engage the floor track, each said trailing edge trolley being connected to its associated said panel for rotation therewith with storage movement of said panel, said dolly having a body providing a platform onto which said wheels turn when said panel is moved into its storage position for supporting the associated said trailing edge trolley against sliding movement on the floor track.