AU2009210405A1 - A suspension arrangement for door panels - Google Patents

Description

1 A SUSPENSION ARRANGEMENT FOR DOOR PANELS FIELD OF THE INVENTION 5 This invention relates to a suspension arrangement for a wing or a wing panel. The invention also extends to a wing assembly including a wing panel and a method of suspending a wing panel from a structure so that it extends across a wing opening. 10 This invention relates particularly but not exclusively to a suspension arrangement for a wing panel that is a sliding door panel that supports the door panel towards its upper end for operatively extending across a door opening and it will therefore be convenient to hereinafter describe the invention with reference to this example application. In one form of the invention the suspension arrangement is for a bi 15 fold sliding door in which the panels are supported overhead and are operatively able to slide in a translational fashion and also to pivot about a vertical axis within the overhead support. However at the same time it must be realized that the invention can find application with other types of sliding doors. For example the invention also applies to simple sliding doors in which the door panels slide in their 20 own vertically extending plane between open and closed positions. The invention could also conceivably be applied to automatic doors and also to doors having door closers. Yet further it must be recognized that the invention also applies to wings other 25 than doors. For example the invention applies equally to wings that are windows, such as sliding windows and bi-fold windows. It also extends to wings that are shutters, such as simple sliding shutters and also bi-fold shutters. Yet further the invention would also extend to simple sliding screens and also bi-fold screens including insect screens, security screens and the like. 30 In this specification the term wing or wing member shall be interpreted broadly and shall include any architectural covering that can be displaced between open and 2 closed positions. It shall be understood to include an architectural covering that is a pivoting door or window or screen panel but it shall not be limited to articles having this property. For example it also includes door and window members that have a simple translational sliding movement as distinct from a pivoting 5 movement. In the specification the term "comprising" shall be understood to have a broad meaning similar to the term "including" and will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the 10 exclusion of any other integer or step or group of integers or steps. This definition also applies to variations on the term "comprising" such as "comprise" and "comprises". BACKGROUND TO THE INVENTION 15 A suspension arrangement for an architectural sliding door or a bi-fold type door may include an overhead support that is mounted on a wall overhead the door. The overhead support may include an elongated track defining a longitudinal traveling path and a wheeled carriage or trolley running on the track along the 20 traveling path. The trolley may include an attachment arrangement for attaching a door panel to the carriage, so that the door panel is suspended from the carriage beneath the track and is displaceable with the trolley along the traveling path of the track for opening and closing the door. 25 A proper operation of the door requires that the wheeled trolley runs easily along the track with a smooth and uninterrupted movement. This enables a user to effect a movement of the associated door panel particularly when the trolley is carrying a load, and when the trolley is being displaced from a stationary position. 30 Further a proper operation of the door also requires the trolley to remain on its track as the trolley is displaced longitudinally along the traveling path without undue vertical movement. Vertical displacement of the trolley is particularly 3 undesirable as this has the propensity to lift the trolley off its track and cause it to derail. It can also cause the door to jam or stick which is undesirable. Clearly therefore it is desirable that any vertical movement of the trolley relative to the track, e.g. lifting of the trolley is controlled. 5 A bi-fold sliding door comprises door panels that are supported overhead and that are operatively able to slide in a translational fashion and also to pivot about a vertical axis within the overhead support. The door panels are arranged end to end in the same plane across a door opening in a closed position. To move the 10 door to the open position each door panel is pivoted transverse to its orientation in the closed position and then the transversely oriented panels are displaced along the track to one end of the door opening. At least some prior art bi-fold doors are susceptible to sticking and jamming when moved between the open and closed positions. This is a drawback that has limited the utility and appeal of bi-fold doors 15 to date. It is clearly desirable that bi-fold doors should be able to travel smoothly between open and closed positions with a minimal effort by a user. They should also be resistant to jamming and sticking when in the open position or when in an intermediate position between the open and closed positions. 20 Clearly therefore it would be advantageous if a suspension arrangement could be devised that facilitated a smooth movement of a door panel along a track. It would be particularly advantageous if the suspension arrangement facilitated a free and easy movement of a bi-fold door from its closed position to its open position. It would be yet further advantageous if the suspension arrangement resisted 25 jumping off its track and being derailed. SUMMARY OF THE INVENTION According to one aspect of this invention there is provided a suspension 30 arrangement for supporting a wing panel such that it is operatively displaceable, which suspension arrangement includes: 4 a support guide mountable adjacent a peripheral side edge of the wing panel, the support guide including a longitudinal track defining at least one longitudinally extending running track support surface and the guide defining at least one further longitudinally extending running track guide surface that is offset 5 relative to said one running track support surface; and a trolley having at least two rotary elements rotatably mounted thereon for rotation about transverse axes of rotation, at least one rotary element being arranged for travel on said at least one running track support surface, and at least 10 one other rotary element being arranged for travel on the at least one offset further running track guide surface. The support guide may be mountable overhead the wing panel, in which case the support guide may include a longitudinal track defining at least one longitudinally 15 extending running track support surface facing in an operatively upward direction, and at least one further longitudinally extending running track guide surface facing in an operatively downward direction. The at least one running track guide surface may be vertically offset relative to said one running track support surface/s and may extend parallel to said one longitudinally extending running support surface. 20 The trolley may include a carriage and at least one load bearing rotary element having a horizontal transverse axis of rotation mounted on said carriage for travel on said running track support surface. The load bearing rotary element may be a wheel or a roller. The trolley may further include at least one guide rotary element 25 for rotation about a horizontal transverse axis of rotation mounted on said carriage for travel on the vertically offset further running track guide surface. The guide rotary element may be a wheel or a roller. In this description generally the term load bearing rotary element refers to a rotary 30 element that runs along the running track support surface. The term guide rotary element refers to a rotary element that runs along the running track guide surface.

5 The suspension arrangement may further include an attachment arrangement for attaching the wing panel to the carriage of the trolley so that the wing panel is operatively linearly displaceable with the trolley along the track. The wing panel may be a door panel. Instead the wing panel may be a window panel or a screen 5 panel. The trolley may include two said load bearing rotary elements that are arranged for travel on one or more said one running track support surfaces and the two load bearing rotary elements may be longitudinally spaced from each other in the 10 longitudinal direction of the track. In one form the track may include two said one running track support surfaces that are laterally spaced from each other and extend parallel to each other, and the two load bearing rotary elements may be laterally offset from each other, in addition to 15 being longitudinally spaced from each other. Thus one load bearing rotary element runs on one running track support surface and the other load bearing rotary element runs on the other running track support surface. The track may include two said running track guide surfaces that are laterally 20 spaced from each other and are arranged to be at substantially the same height as each other. The further track guide surface may extend in a parallel offset relationship to said one track support surface and may face in an opposite direction to said one longitudinally extending running track support surface. 25 The trolley may include two said guide rotary elements that are offset from each other in a longitudinal direction and are also laterally spaced from each other, so that one guide rotary element runs on one running track guide surface and the other guide rotary element runs on the other running track guide surface. 30 In another form the track may include a single said one running track support surface, and both load bearing wheels may be longitudinally spaced apart from 6 each other and aligned with each other, so that they both run along said one running track support surface. In particular the bottom wall portion may define an upwardly facing said one 5 running track support surface, and the top wall may define the opposing downwardly facing further running track guide surface. In such a case, the trolley may include two support rotary members in the form of two longitudinally spaced support wheels mounted about spaced apart horizontal axes of rotation. 10 The trolley may include at least one load bearing rotary element or support wheel rotatably mounted on each side of the carriage for cooperation with and running along said one upwardly facing running track surfaces. In the other form of the invention defined above the support guide may include one 15 running track guide surface, and the trolley may include one said guide rotary element that is positioned longitudinally intermediate the two load bearing rotary elements and is arranged in the same plane as the load bearing rotary elements. In this form the track may include one said further running track guide surface positioned above said one running track support surface. 20 Each running track support surface may have a transverse profile of a certain shape, and the transverse tread profile of each load bearing rotary element that runs on said support surface may have a complementary shape. Further each running track guide surface may have a transverse profile of a certain shape and 25 the transverse tread profile of each guide rotary element that runs on said guide surface may have a complementary shape. Each running track support surface may have a transverse section of curved shape or a transverse section having two or more facets. Further each running 30 track guide surface may have a transverse section of curved shape or a transverse section having two or more facets.

7 The support guide may include an elongated channel member of general inverted U-shaped section defining a channel interior. In one form of the invention the channel member may include a longitudinal top 5 wall defining two transversely spaced apart downwardly facing further running track guide surfaces, two horizontally transversely spaced opposing sidewalls, and two longitudinally extending bottom wall portions having inner side edges between which a longitudinal aperture is formed. 10 Each bottom wall portion may define an upwardly facing said one running track support surface. The channel member may be unitary in construction. That is, the top wall, the two transversely spaced opposing sidewalls, and the two longitudinally extending 15 bottom wall portions may be integrally formed. For example, the channel member may be formed as a single piece from a metal alloy extrusion such as an aluminum extrusion having a constant transverse cross-section. In another form of the invention the channel member may also include a 20 longitudinal top wall, two horizontally transversely spaced opposing sidewalls, and two longitudinally extending bottom wall portions having inner edges, e.g. long sided edges, between which a longitudinal aperture is defined. The channel member may be a two part construction, and may include two 25 elongated channel member parts that are detachable attachable to each other. The two channel member parts may each be formed by an extrusion having a constant transverse cross-section. The suspension arrangement may be manufactured with a fine tolerance such that 30 the load bearing wheels and the guide wheels both engage said one running track support surfaces and said further running track guide surfaces with a snug fit when the trolley is mounted on the support guide.

8 In particular the elongated channel member may be extruded with a fine tolerance so that said one running track support surfaces and said further running track guide surfaces are very precisely and accurately positioned. Further the trolley 5 with the carriage and load bearing rotary elements and the guide rotary elements may be precision engineered and precision manufactured so as to closely match and fit the fine tolerance running track support and guide surfaces. This helps to facilitate minimal to and fro movement, or rattling movement, of the trolley when it is mounted on said one and further running track surfaces. 10 The attachment arrangement may include a shank depending from the carriage and protruding through the elongated aperture defined between the opposing long side edges of the bottom wall sections, and one end portion of the shank may be rotatably connected to the carriage for rotation about a vertically extending 15 longitudinal axis of the shank, and an opposite end portion may be for attachment to an edge of the wing panel. The opposite end portion may be configured for attachment to an upper edge of the wing panel. For example the opposite end region of the shank may have an 20 external screw thread for screw threadingly engaging a complementary screw threaded bore on the wing panel. Instead the attachment arrangement may include a clamp mounted on the opposite end portion of the shank for clamping to an upper edge of the wing panel. 25 According to another aspect of the invention there is provided a suspension arrangement for a slidable and/or vertically pivotal door panel, which suspension arrangement includes: a support guide mountable above or below the door panel, the support 30 guide including a longitudinal track defining at least one longitudinally extending running track support surface and an opposing further running track guide surface; 9 a trolley having a carriage and at least two rotary elements rotatably mounted about transverse axes of rotation on the carriage, at least one load bearing rotary element being for cooperating with said one running track support surface and at least one other guide rotary element being for cooperating with the 5 opposing said further running track guide surface, the co-operation of said rotary elements with said opposing running track support and guide surfaces resisting the carriage from jumping off said running track support surface in a direction transverse to said support surface; and 10 an attachment arrangement for attaching the door panel rotatably about a vertical axis. The support guide may include an elongated channel member of general inverted U-shaped section defining a channel interior. The channel member may include a 15 longitudinal top wall, two horizontally transversely spaced opposing sidewalls, and two longitudinally extending bottom wall portions having inner long side edges between which a longitudinal aperture is defined. Both bottom wall portions or sections may define upwardly facing said one running 20 track support surfaces and the trolley may include at least two load bearing rotary elements that are support wheels rotatably mounted on either transverse side of the carriage for running on the upwardly facing said one running track support surfaces. The two support wheels may be mounted diagonally opposite each other and may be rotatable about a horizontally extending rotational axis. 25 The upwardly facing said one running track support surfaces may be generally concave in transverse section and the transverse tread profile of the support wheels may be complementary convex in transverse profile. 30 The top wall may define two parallel extending spaced downwardly facing said further track guide surfaces, e.g. opposed to the two said one upwardly facing running track support surfaces, and the trolley may include at least two guide 10 rotary elements that are guide wheels rotatably mounted on either side of the carriage, for cooperating with or engaging with, the downwardly facing said further running track guide surfaces. The two guide wheels may be mounted diagonally opposite each other and each guide wheel may be rotatable about a horizontally 5 transverse rotational axis. The downwardly facing further running track guide surfaces may each have two facets in transverse section, and the guide wheels may include wheel treads that are complementary shaped to the downwardly facing further running track guide 10 surfaces. Thus, the trolley may include a carriage having two support wheels diagonally opposite each other towards either end of the carriage for running in said one running track support surfaces, and two guide wheels mounted vertically offset 15 relative to the support wheels and diagonally opposite each other for cooperating with the downwardly facing further running track guide surfaces defined by the top wall. The attachment arrangement may include a shank depending from the carriage 20 and protruding through the elongated aperture defined between the opposing long side edges of the bottom wall sections. One end portion of the shank may be rotatably connected to the carriage for rotation about a vertically extending longitudinal axis of the shank, and an opposite end portion may be for attachment to an edge of the wing panel. 25 The opposite end portion may be configured for attachment to an upper edge of the wing panel. For example the opposite end region of the shank may have an external screw thread for screw threadingly engaging a complementary bore on the wing panel. Instead the attachment arrangement may include a clamp 30 mounted on the opposite end portion of the shank for clamping to an upper edge of the wing panel.

11 The channel member may be unitary in construction so that the top wall, two transversely spaced opposing sidewalls, and two longitudinally extending bottom wall portions may be integrally formed. The channel member may be an extrusion having constant transverse section, e.g. a metal alloy extrusion, such as an 5 aluminum extrusion. The suspension arrangement may include any one or more of the other features of the suspension arrangement defined in the first aspect of the invention. 10 According to another aspect of this invention there is provided a suspension arrangement for an overhead supported sliding door panel, which suspension arrangement includes: an elongated support mountable overhead the door panel on a wall defining 15 the door opening, the elongated support having a longitudinally extending track defining an upwardly facing running track support surface opposite a downwardly facing further running track guide surface; a trolley having a carriage and at least three wheels mounted rotatably on 20 the carriage about transverse rotation axes and the wheels also generally mounted in the same plane, two said wheels being support wheels that run along the upwardly facing said one running track support surface, and one said wheel being a guide wheel that is vertically offset from the support wheels and that runs along the opposite downwardly facing said further running track guide surface; and 25 an attachment arrangement for attaching the door panel to the carriage of the trolley. The guide wheel may be positioned longitudinally intermediate the two support 30 wheels. Further the guide wheel may be arranged with its major surfaces aligned in the same plane as the major surfaces of the support wheel.

12 The support guide may include an elongated channel member of inverted generally U-shaped section defining a channel interior. The channel member may include a longitudinal top wall, two horizontally transversely spaced opposing sidewalls, and two longitudinally extending bottom wall portions having inner 5 edges, e.g. long sided edges, between which a longitudinal aperture is defined. The channel member may be a two part construction, and may include two elongated channel member parts that are detachable attachable to each other. One channel member part may be formed by one side wall integrally formed with 10 its associated bottom wall, and the other channel member part may include the top wall integrally formed with the other side wall and its associated bottom wall. Thus, the one channel part may be a cover member that is detachably attachable to the other channel member part, that may be a bracket mountable overhead the door panel on a wall defining the door way. 15 The channel member may include a longitudinally extending intermediate wall that projects into the interior of the channel member orthogonally away from an inside surface of one side wall, and the downwardly facing track surface may be defined by an underside of the intermediate wall for cooperating with the guide wheel. 20 The intermediate wall and the top wall may be spaced apart so as to define a space for receiving a door closer there between, the door closer being operatively attached to the carriage of the trolley for driving the trolley along the track. 25 The two parts of the channel member may be formed by a section having a constant transverse section. For example, the channel member or the two parts of the channel member may be formed from a metal alloy extrusion such as an aluminium extrusion. 30 The channel member may include a bottom wall opposite the intermediate wall, and the bottom wall may define the upwardly facing running track surface for co operating with the two support wheels.

13 Thus, the carriage may include an elongated carriage body and the two support wheels may be mounted towards each end of the carriage in substantially the same plane for running on the upwardly facing running track support surface. The 5 guide wheel may be mounted such that it is vertically offset relative to the support wheels, and positioned intermediate the support wheels, for cooperating with the downwardly facing running track guide surface defined by the underside of the intermediate wall. 10 The upwardly facing running track support surface may be generally concave in transverse section, and the transverse tread profile of the support wheels may be convex in transverse profile, complementary to the transverse profile of the upwardly facing running track. 15 The downwardly facing running track guide surface may have at least two facets in transverse section, and the guide wheel may have a tread profile matching the faceted transverse section of the downwardly facing track. The attachment arrangement may include a clamp forming part of the trolley for 20 clamping attachment to an upper end of the door panel, so that the door panel is suspended from the carriage for displacement with the carriage along the track. The door closer may include a telescopically extendible door closer body having one end mounted towards an end of the channel member and another end 25 mounted to the carriage. The suspension arrangement may include a stop towards an end of the track for stopping the trolley towards the end of the track. 30 The suspension arrangement may include any one or more of the features of the suspension arrangement defined in any one of the preceding aspects of the invention.

14 The invention extends to a sliding door system which includes a suspension arrangement as defined in any one of the preceding aspects of the invention, and at least one door panel suspended from the suspension arrangement. 5 The suspension arrangement may include any one or more of the optional features of the suspension arrangement defined in any one of the preceding aspects of the invention. 10 Each door panel may be glass door panel or a wooden door panel and may be capable of translational sliding movement along the longitudinal track of the suspension arrangement. Instead the door panel may be capable of rotational pivoting relative to the longitudinal track on which it is mounted as well as translational sliding movement along the longitudinal track. 15 The sliding door system may be a simple in plane sliding door system or a bi-fold sliding door system. The invention also extends to a foldable wing system that includes, a suspension 20 arrangement as defined in any one of the preceding aspects of the invention, and a wing panel suspended by the suspension arrangement. The suspension arrangement may include any one or more of the features of the suspension arrangement defined in any one of the preceding aspects of the 25 invention above. The wing panel may be a door panel for a sliding door. In particular the door panel may be a panel for a bi-fold sliding door. Instead the wing panel may be a screen panel or a window panel or a shutter panel. 30 The invention also extends to a method of suspending a wing member from a wing support defining a wing opening, so that it can be translationally displaced from a 15 closed position extending across the wing opening to an open position, the method including: mounting a support guide overhead the wing opening, which support 5 includes an elongated track having at least one running track support surface and at least one further running guide surface guide that is arranged in opposition to said one running track support surfaces; providing a wheeled trolley having a carriage and at least one wheel 10 rotatably mounted about a horizontal transverse rotational axis on the carriage for cooperating with said one running track support surface, and at least one other wheel mounted on the carriage vertically offset relative to the one wheel about a horizontal transverse rotational axis for cooperating with the opposing running track guide surface; and 15 attaching the wing member towards its upper end to the carriage for displacement with the carriage along the track. The support guide may include mounting a support guide as described in any one 20 of the preceding aspects of the invention. Similarly the wheeled trolley may include a trolley as described in any one of the preceding aspects of the invention. The wing member may be an architectural covering. For example the architectural covering may be a door and in particular the wing member may be a sliding door 25 panel, e.g. a bi-fold door panel. The attaching may be accomplished by using an attachment arrangement mounted on the trolley to attach an upper edge of the wing member to the trolley and thereby also support the wing member on the support guide. In one form the 30 attaching may comprise clamping an upper edge of the wing member to the wheeled trolley. In another form attaching may comprise engaging a screw threaded shank with a complementary screw threaded bore in the wing member 16 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A suspension arrangement for a wing member such as a door panel for a bi-fold 5 door and a sliding door system in accordance with this invention may manifest itself in a variety of forms. It will be convenient to hereinafter describe several embodiments of the invention in detail with reference to the accompanying drawings. The purpose of providing this detailed description is to instruct persons having an interest in the subject matter of the invention how to carry the invention 10 into practical effect. However it is to be clearly understood that the specific nature of this detailed description does not supersede the generality of the preceding broad description. In the drawings: Figure 1 shows a three-dimensional view of a bi-fold sliding door system including 15 a suspension arrangement in accordance with one embodiment of the invention that is operatively mounted on a support structure; Figure 2 shows a three dimensional view of the suspension arrangement forming part of the foldable door system shown in Figure 1; 20 Figure 3 shows an end view of the suspension arrangement of Figure 2; Figure 4 shows a side elevation of the suspension arrangement of Figure 2; 25 Figure 5 shows a top plan view of the suspension arrangement of Figure 2; Figure 6 shows a three-dimensional view of another sliding door system fitted with a suspension arrangement in accordance with another embodiment of the invention; 30 Figure 7 shows a front elevation of a part of the suspension arrangement used in the sliding door system shown in Figure 6; 17 Figure 8 shows a side elevation of the suspension arrangement of Figure 7; Figure 9 shows a side elevation of one part of the suspension arrangement of 5 Figure 7; and Figure 10 shows a side elevation of another part of the support of the suspension arrangement of Figure 7. 10 Figure 1 shows an architectural covering system that is a bi-fold sliding door system for extending across an architectural opening that is the bi-fold door opening. The bi-fold door system is indicated generally indicated by reference numeral 10 15 and includes a plurality of door panels, each of which is indicated by reference numeral 12, and a suspension arrangement that is generally indicated by reference numeral 14. Figure 2 illustrates the suspension arrangement 14 for the bi-fold door assembly 20 10 of Figure 1 in more detail. The suspension arrangement 14 supports the door panels 12 in their position within the architectural opening such that they are operatively linearly displaceable within the opening. Specifically the suspension arrangement 14 is able to suspend 25 each door panel 12 so that it is pivotable about a vertical axis and also linearly slidable across the opening. The suspension arrangement 14 includes a support guide 16 that is mountable overhead the sliding door panel 12 and a trolley 94 that runs in the support guide 30 16. The support guide 16 includes a longitudinal track 82 that defines two pairs of longitudinally extending opposing running track surfaces. These include a pair of 18 upwardly facing track support surfaces 86 and 88, and also a pair of downwardly facing track guide surfaces 90 and 92. The trolley 94 includes a carriage 96 and has four rotary elements that are 5 rotatably mounted thereto. Two said rotary elements 98, 100 are in the form of load bearing rotary elements that are load support wheels for cooperating with the upwardly facing running track support surfaces 86, 88. The other two rotary elements 102, 104 are in the form of guide rotary elements that are guide wheels for cooperating with the downwardly facing running track guide surfaces 90, 92. 10 The guide wheels 102, 104 guide the trolley 94 smoothly along the track 82 and also resist displacement of the carriage 90 in an upward direction, e.g. to stop it jumping off the track 82. Each rotary element 98, 100, 102, 104 is rotatably mounted about a horizontal transverse axis of rotation on the carriage 96. 15 The track 82 is formed by an elongated channel member of general inverted U shaped section that is unitary in construction. The channel member 82 includes a longitudinal top wall 108, two horizontally transversely spaced opposing sidewalls 110, 112, and two longitudinally extending bottom wall portions or sections 114, 116 having inner long side edges 118, 120 between which a longitudinal aperture 20 122 is defined. The walls together define a channel interior 106. In the illustrated embodiment the top wall 108, the two transversely spaced opposing sidewalls 110, 112, and the two longitudinally extending bottom wall portions 118, 120 are conveniently integrally formed by a single aluminum extrusion having a constant transverse section. 25 The bottom wall sections 114, 116 define the upwardly facing running track support surfaces 86, 88 on along which the two support wheels 98 and 100 are displaced. Each of the upwardly facing running tracks 88, 86 is generally concave in transverse profile, and the transverse tread profile of the support wheels 98, 100 30 is of a complementary convex shape. This facilitates snug fitment of the support wheels 98, 100 in the track surfaces 86, 88 and smooth rolling engagement with the running track support surfaces 86, 88. The two support wheels 98, 100 are 19 mounted on each lateral side of the carriage 96 in positions that are diagonally opposite each other as shown in the drawings and particularly in Figure 5. The top wall 108 defines the two downwardly facing running track guide surfaces 5 90, 92 opposite the two upwardly facing running track support surfaces 86, 88. The guide wheels 102, 104 are mounted in vertically offset positions relative to the support wheels 98, 100. The downwardly facing running track support surfaces 90, 92 are faceted and include two longitudinally extending faces or facets 128, 130 that are flat when viewed in transverse section. The guide wheels 102, 104 10 include wheel treads that are of complementary faceted shape to the downwardly running track surfaces. In other words the guide wheels 102, 104 include circumferentially extending flat tread faces 124, 126 for snug fitment in the downwardly facing running tracks 90, 92. The two guide wheels 102, 104 are mounted diagonally opposite each other on lateral sides of the carriage 96 as 15 shown in Figure 5 and they occupy the two diagonal positions left vacant by the support wheels 98, 100. The trolley 94 further includes an attachment arrangement, generally indicated by reference numeral 132, for attaching the door panel 12 to the carriage 96 so that it 20 is rotatable about a vertical axis. The attachment arrangement includes a shank 134 depending from the carriage 96 having a lower end portion for attaching to an upper edge of the sliding door panel. An upper end portion of the shank 134 is rotatably connected to the carriage 96 for rotation about a vertically extending longitudinal axis of the shank 134. The shank 134 projects through the elongated 25 aperture defined between the opposing long side edges of the bottom wall. The lower end portion of the shank 134 includes a screw thread 136 towards its free end for attaching to an upper end portion of the door panel 12 by means of a screw threaded engagement. 30 In use, the suspension arrangement 14 facilitates a smooth and easy movement of the door panels 12 between a closed position in which the panels 12 extend across the door opening and a folded open position in which the door panels 12 20 are folded up against each other at one side of the door opening. This movement includes a pivoting movement of each door panel 12 relative to the track 82 on the support guide 16. It also involves a translational sliding of the attachment arrangement 132 and the door panel 12 along the track 82 on the support guide 5 16 to move it to one side of the door opening. The suspension arrangement 14 illustrated in Figures 2 to 6 supports and guides each door panel 12 to encourage the pivoting and sliding movement of each door panel 12 to occur smoothly without any jamming or sticking of the door panels 12. 10 Further the two guide rollers 102, 104 by bearing against a downwardly facing running surface forming tracks 90, 92 inhibit any vertical movement of the trolley 94 and thereby resist jumping of the trolley 94 on the track 82. The illustrated suspension arrangement 14, by having two guide rollers 102 and 15 104 that bear against the downwardly facing running track guide surface 90 or 92, in addition to the weight or load bearing support rollers 98 and 100, helps to achieve this. The weight bearing support rollers 98, 100 and the guide rollers 102, 104 have a fine dimensional tolerance so that the trolley 94 and specifically the rollers thereof, are snugly and evenly received between the opposed running 20 surfaces with a tight fit or close fit. This aids smooth running of the suspension arrangement 14 and resists any jumping of the rollers on the track. Further the fine tolerance double faceted tread surface on the guide rollers 102, 104 effectively guides the guide rollers 102, 104 along the further running track 25 guide surfaces 90, 92. Further the angle of the facets helps to direct the return force applied by the running track guide surface in the most effective direction and this helps to facilitate smooth travel without interruptions along the support guide 16. 30 By having two laterally spaced and diagonally arranged support rollers 98, 100 and two laterally spaced diagonally arranged guide rollers 102, 104 a trolley 94 having an exceptionally smooth and stable ride without jumping is provided.

21 In summary the suspension arrangement 14 described above with reference to Figures 2 to 5 guides displacement of the trolley 94 in the track 82 in a certain direction and resists it being moved in other directions. In the case that the suspension arrangement 14 is mounted overhead the wing, as described above, 5 then the suspension arrangement 14 resists vertical displacement of the trolley 94 in the track 82 and hence displacement of the wing vertically. It is not an essential requirement however, that the suspension arrangement 14 be used with downwardly depending wings to carry out this invention. 10 The fine tolerance fitment of the wheels 98, 100, 102, 104 in the track 82 resists transverse movement of the trolley 94 in a direction extending between the track surfaces and this resistance is achieved irrespective of the physical spatial orientation of the suspension arrangement 14. Consequently, the suspension arrangement 14 can equally be applied for supporting wings, such as doors and 15 windows, slidably along their operative upright or lower side edges. For example the support guide could be mounted beneath the wing panels and the wing panels could extend up from a support guide extending along a support surface, e.g. along a length of a door opening. 20 Yet further the suspension arrangement 14 can be used to suspend a wing in an oblique orientation in relation to the horizontal such as occurs on a sloping roof. In this case, the wing may exert a tilting force on the trolley 94 in the track 82. If a transverse tilting force is applied to the trolley (see arrow 95), then wheel 95 would attempt to lift off its track surface 86. Because of the fine tolerances between the 25 wheels and tracks, the opposing roller 97 immediately reacts on its track surface as soon as the trolley 94 attempts to tilt and thus resists further movement of roller 95 before it leaves its track. Moreover, the flat faceted contact surfaces of roller 97 and its complementary shaped track surfaces are angled in such a way that they abut face-on with each other when the trolley 94 attempts to tilt transversely, 30 and thus is less prone to allowing a cam-like action of the track surface on the tread when the trolley tilts transversely. For example the wings could extend at an angle of 20 degrees to 30 degrees to the vertical axis.

22 Also, a space or gap 99 is defined between major side surfaces of the wheels 98, 100, 102, 104 and the inside surfaces of the side walls 110, 112, and the tolerances between the wheels and the tracks are selected so that the tilting 5 movement of the wheels causes a reaction between the wheels and the tracks before the side circular surfaces or part thereof can bridge the gaps 99 to interfere with the inner side surfaces of the side walls 110, 112. This allows the exertion of a tilting force 95 without causing interference between the wheels 98, 100, 102, 104 and the side walls 110, 112, thus still permitting smooth and easy rolling 10 displacement of the wheels along their tracks. Figures 6 to 10 show a suspension arrangement in accordance with another embodiment of the invention. As this suspension arrangement has some similarities with the suspension arrangement in Figs 2 to 5 the same reference 15 numerals will be used to refer to the same components unless otherwise indicated. In Figures 6 to 10 a sliding door assembly or a sliding door system is generally indicated by reference numeral 20. 20 The sliding door system 20 has door panels 22 in the form of glass door panels that are displaceable across a door opening with a simple translational sliding movement in the plane of the door panels 22. The sliding door system 20 includes a suspension arrangement that is indicated 25 generally by reference numeral 18 that includes an elongated support 24 mountable overhead the door panel 22 on a wall defining the door opening. The elongated support 24 has a longitudinally extending track 26 defining an upwardly facing track surface 28 opposite a downwardly facing further track surface 30. 30 The suspension arrangement 18 further includes a trolley, generally indicated by reference numeral 32, having a carriage 34 and at least three rotary elements in 23 the form of three wheels 36, 38, 40 each of which is mounted rotatably about a transverse rotational axis. The three wheels 36, 38 and 40 are arranged broadly in the same vertical plane, 5 e.g. with their major surfaces broadly in plane with each other. Two of the wheels 36 and 38 are support wheels for running along the one bottom track surface 28. The support wheels 36 and 38 thus carry the weight of the door panel 22 on the support guide in a way that permits the trolley to slide in a translational fashion along the guide. 10 The other wheel 40 is a guide wheel vertically offset from the support wheels 36, 38 for running along the downwardly facing further track surface 30 opposite to said upwardly facing running track surface 30. The guide wheel 40 is snugly received within the downwardly facing running track surface 30 thereby resisting 15 upward or vertical displacement of the trolley 32, in use. It also assists in guiding the travel of the trolley member 32 along the track 26 and thereby also helps to facilitate smooth travel of the trolley member along the track 26. The suspension arrangement 18 also includes an attachment arrangement, 20 generally indicated by reference numeral 42 for attaching the door panel 22 to the carriage 34 of the trolley 32. The attachment arrangement 42 is in the form of a clamp and is attached to the trolley 32 for clamping attachment to an upper end of the door panel 22. This causes the door panel 22 to be suspended from the carriage 34 for displacement with the carriage 34 along the track 26. 25 The track 26 is in the form of an elongated channel member of general inverted U shaped section defining a channel interior 44 as shown in Figures 8 to 10. The channel member 26 includes a longitudinal top wall 46, two horizontally transversely spaced opposing sidewalls 48, 50, and two longitudinally extending 30 bottom wall portions 52, 54 having inner long sided edges 56, 58 between which a longitudinal aperture 60 is defined.

24 In the illustrated embodiment shown in Figures 9 and 10, the channel member 26 is formed from a two part construction including two channel member parts 62 and 64 that are detachably attached to each other. Each part 62 and 64 is conveniently formed from an aluminum extrusion of constant cross section. 5 The one channel member part 62 is formed by one sidewall 50 integrally formed with its associated bottom wall 54. The other channel member part 64 includes the top wall 46 integrally formed with the other side wall 48 and its associated bottom wall section 52. Complementary clip or snap-fit formations 66, 68 are 10 formed at upper ends of the two channel part 62, 64 for attaching the two panel parts 62, 64 to each other in a releasable fashion. Thus, the one channel part 62 forms an elongated cover or lid member that is detachably attachable to the other channel member 64. This forms an elongated 15 bracket member defining the track 26 that is mountable overhead the door panel 22 defining the doorway. The bracket member 64, in this example, includes a longitudinally extending intermediate wall 70 that projects into the interior 44 of the channel member 24 20 orthogonally away from an inside surface of one side wall 48. The downwardly facing track surface 30 is defined an underside of the intermediate wall 70 for cooperating with the guide wheel 40. The intermediate wall 70 is spaced away from the top wall 46 so that a space is 25 defined between the wall 70 and wall 46 for housing a door closer 72 that is operatively attached at one end to the support 24 and at its other end to the carriage 34 of the trolley 32. The door closer 72 is of the type having a telescopically extendible door closer body that extends and retracts to drive the trolley 36 along the track 26. 30 An elongated flange 74 projects upwardly from the intermediate wall 70 and is spaced away from the long edge of the intermediate wall 70 so that a rectangular 25 cutaway 76 is defined between the flange 74 and the wall 70. The cutaway 76 serves as a guide passage for a complementary shaped formation of an end part 78 of the door closer 72. 5 The upwardly facing running track surface 28 is generally concave in transverse section and the transverse tread profile of the support wheels 36, 38 is complementary convex in shape to the transverse profile of the upwardly facing running track 28. 10 The downwardly facing running track surface 30 in this example is flat or broadly planar, e.g. horizontally extending planar, and the transverse profile of the guide wheel 40 is also flat. However, in another embodiment the downwardly facing track surface can have a faceted or rounded transverse section, and the guide wheel can have a tread profile matching the faceted or rounded transverse section 15 of the downwardly facing track. The faceted transverse section could be similar to that described above with reference to the folding door suspension arrangement in Figures 2 to 5. The rounded transverse section could be similar to the rounded transverse section of the support wheels in this embodiment. 20 The suspension arrangement 20 also includes a stop 80 towards an end of the track 26 for stopping the trolley 32 towards the end of the track 26. In use the suspension arrangement 20 facilitates sliding movement of the door panels 22 between a closed position in which they extend across the door opening 25 and an open position in which they are displaced outwardly to define a door opening through which people can pass. The guide roller 40 that bears against the downwardly facing running track helps to facilitate smooth and easy translational sliding movement of the door panels 22. 30 The weight bearing and guide rollers are manufactured with a fine dimensional tolerance so that the trolley and specifically the rollers thereof are snugly received between the opposed running surfaces with a tight fit. This aids in smooth running 26 of the suspension arrangement and also resists any form of jumping or jamming of the trolley. Further in another embodiment similar to that described immediately above with 5 reference to Fig 6 that has not been illustrated, the support wheels have faceted transverse sections as has been described above in place of the support wheels with the rounded transverse section. An advantage of both the Figure 2 and the Figure 6 embodiments of the door and 10 suspension arrangements described above with reference to the drawings is that they are capable of smooth travel along their tracks. The Figure 2 suspension arrangement facilitates a particularly smooth travel of the door panels on a bi-fold door where the panels are pivoted and also when the 15 panels are displaced. Further the panels are not inclined to jam when the bi-fold door is in an open position and it is desired to close the door. This is a particularly useful advantage of this design as it is recognized that prior art suspension arrangements for bi-fold doors are often susceptible to sticking and jamming. 20 A yet further advantage of the suspension arrangement described above with reference to Figure 2 is that it resists the door panel from jumping off its track. It does this because the guide rotary element bears against a downwardly facing running track surface thereby constraining any movement in a vertical direction, e.g. a vertical jumping movement. That is the support rotary members and the 25 guide rotary members bear against upper and lower supports and thereby hold the suspension arrangement in a fixed vertical position. A yet further advantage of the suspension arrangement described above is that the structural feature that resists the trolley from jumping off the track is integrated 30 up with the load support and guiding function of the trolley. It is essentially the same features that confer both working advantages, namely the smooth travel of 27 the trolley and resisting the trolley from jumping off its track. It is not an add-on feature that adds mechanical complexity to the suspension arrangement. A yet further advantage of the suspension arrangement described above with 5 reference to the drawings is that the profile of the rotary elements, and in particular the guide rotary elements, can be configured to confer an optimum guiding and retaining effect and need not be semi-circular. For example, a profile having two facets extending at an angle to each other has been found to be very efficacious in operation. 10 A yet further advantage of the suspension arrangement described above with reference to the drawings is that the channel guide for cooperating with the trolley is of constant cross section and can be extruded using conventional extrusion techniques. For example it can be extruded from aluminium in a one piece form. 15 It can also be extruded in two pieces which are then attached together. A yet further advantage of the suspension arrangement described above is that the trolley with its two load bearing rotary elements and two guide rotary elements does not have an unduly complex construction and the manufacturing thereof is 20 not unduly complex. It is also capable of reliable and low maintenance operation in use. It will of course be realised that the above has been given only by way of illustrative example of the invention and that all such modifications and variations 25 thereto, as would be apparent to persons skilled in the art, are deemed to fall within the broad scope and ambit of the invention as is herein set forth.

Claims (20)

1. A suspension arrangement for supporting a wing panel such that it is operatively displaceable, which suspension arrangement includes: 5 a support guide mountable adjacent a peripheral side edge of the wing panel, the support guide including a longitudinal track defining at least one longitudinally extending running track support surface and the guide defining at least one further longitudinally extending running track guide surface that is offset 10 relative to said one running track support surface; and a trolley having at least two rotary elements rotatably mounted thereon for rotation about transverse axes of rotation, at least one rotary element being arranged for travel on said at least one running track support surface and at least 15 one other rotary element being arranged for travel on the at least one offset further running track guide surface.

2. A suspension arrangement according to claim 1, wherein the support guide is mountable overhead the wing panel, in which case the support guide includes a 20 longitudinal track defining at least one longitudinally extending running track support surface facing in an operatively upward direction, and at least one further longitudinally extending running track guide surface facing in an operatively downward direction that is vertically offset relative to said one running track support surface/s and extends parallel to said one longitudinally extending running 25 support surface.

3. A suspension arrangement according to claim 2, wherein the trolley includes a carriage and at least one rotary element that is a wheel or roller having a horizontal transverse axis of rotation mounted on said carriage for travel on said 30 running track support surface, and at least one rotary element that is a wheel or roller for rotation about a horizontal transverse axis of rotation mounted on said carriage for travel on the vertically offset further running track guide surface, and 29 wherein the suspension arrangement further includes an attachment arrangement for attaching the wing panel to the carriage of the trolley so that the wing panel is operatively linearly displaceable with the trolley along the track. 5

4. A suspension arrangement according to claim 3, wherein the trolley includes two said load bearing rotary elements that are arranged for travel on said one running track support surface and that are longitudinally spaced from each other in the longitudinal direction of the track. 10

5. A suspension arrangement according to claim 4, wherein the track includes two said one running track support surfaces that are laterally spaced from each other and extend parallel to each other, and wherein the two load bearing rotary elements are laterally offset from each other, in addition to being longitudinally spaced from each other, so that one load bearing rotary element runs on one 15 running track support surface and the other load bearing rotary element runs on the other running track support surface.

6. A suspension arrangement according to claim 5, wherein the track includes two said running track guide surfaces that are laterally spaced from each other 20 and are arranged to be at substantially the same height as each other, and wherein the trolley includes two said guide rotary elements that are offset from each other in a longitudinal direction and are also laterally spaced from each other, so that one guide rotary element runs on one running track guide surface and the other guide rotary element runs on the other running track guide surface. 25

7. A suspension arrangement according to claim 4, wherein the guide track includes a single said one running track support surface and both load bearing wheels are longitudinally spaced apart from each other and are aligned with each other so that they both run along said one running track support surface. 30

8. A suspension arrangement according to claim 7, wherein the support guide track includes one running track guide surface, and the trolley includes one said 30 guide rotary element that is positioned longitudinally intermediate the two load bearing rotary elements and is arranged in the same plane as the load bearing rotary elements. 5

9. A suspension arrangement according to claim 6, wherein the support guide includes an elongated channel member of general inverted U-shaped section defining a channel interior, and the channel member includes a longitudinal top wall defining two transversely spaced apart downwardly facing further running track guide surfaces, two horizontally transversely spaced opposing sidewalls, and 10 two longitudinally extending bottom wall portions having inner side edges between which a longitudinal aperture is formed, and wherein each bottom wall portion defines an upwardly facing said one running track surface.

10. A suspension arrangement according to claim 9, wherein each running 15 track support surface has a transverse profile of a certain shape and the transverse tread profile of said one rotary element that runs on said support surface has a complementary shape, and wherein each running track guide surface has a transverse profile of a certain shape and the transverse tread profile of said one rotary element that runs on said guide surface has a complementary 20 shape thereto.

11. A suspension arrangement according to claim 10, wherein each running track support surface has a transverse section of curved shape or a transverse section having two or more facets, and wherein each running track guide surface 25 has a transverse section of curved shape or a transverse section having two or more facets.

12. A suspension arrangement according to any one of claims 1 to 11, wherein the attachment arrangement includes a shank depending from the carriage and 30 protruding through the elongated aperture defined between the opposing long side edges of the bottom wall sections, and wherein one end portion of the shank is rotatably connected to the carriage for rotation about a vertically extending 31 longitudinal axis of the shank, and an opposite end portion is for attachment to an edge of the wing panel.

13. A suspension arrangement for a slidable and/or vertically pivotal door 5 panel, which suspension arrangement includes: a support guide mountable above or below the door panel, the support guide including a longitudinal track defining at least one longitudinally extending running track support surface and an opposing further running track guide surface; 10 a trolley having a carriage and at least two rotary elements rotatably mounted about horizontal transverse axes of rotation on the carriage, at least one rotary element being for cooperating with said one running track support surface and at least one other rotary element being for cooperating with the opposing said 15 further running track guide surface, the co-operation of said rotary elements with said opposing running track support and guide surfaces resisting the carriage from jumping off said running track support surface in a direction transverse to said support surface; and 20 an attachment arrangement for attaching the door panel rotatably about a vertically extending axis.

14. A suspension arrangement for a slidable and/or vertically pivotal door panel according to claim 13, wherein the support guide includes an elongated channel 25 member defining an interior and including a longitudinal top wall, two horizontally transversely spaced opposing sidewalls, and two longitudinally extending bottom wall portions having inner long side edges between which a longitudinal aperture is defined. 30

15. A suspension arrangement for a slidable and/or vertically pivotal door panel according to claim 14, wherein both bottom wall sections define upwardly facing running track support surfaces, and the trolley includes at least two said rotary 32 elements in the form of support wheels rotatably mounted on either transverse side of the carriage for running on the upwardly facing running track support surfaces. 5

16. A suspension arrangement for a slidable and/or vertically pivotal door panel according to claim 15, wherein the upwardly facing running track support surfaces are generally concave in transverse section, and wherein the transverse tread profile of the support wheels are of complementary convex transverse profile. 10

17. A suspension arrangement for a slidable and/or vertically pivotal door panel according to claim 16, wherein the top wall defines two parallel extending spaced downwardly facing further running track guide surfaces, and the trolley includes at least two said further rotary elements in the form of guide wheels rotatably mounted on either side of the carriage for engaging with the downwardly facing 15 said further running track guide surfaces.

18. A suspension arrangement for a slidable and/or vertically pivotal door panel according to claim 17, wherein the two support wheels are mounted diagonally opposite each other, and are rotatable about a horizontally extending rotational 20 axis, and the two guide wheels are mounted diagonally opposite each other, and are rotatable about a horizontally extending rotational axis.

19. A suspension arrangement for a slidable and/or vertically pivotal door panel according to claim 17 or claim 18, wherein the downwardly facing further running 25 track surfaces each have two facets in transverse section, and the guide wheels include wheel treads that are of complementary transverse section to the downwardly facing further running track surfaces.

20. A suspension arrangement for a slidable and/or vertically pivotal door panel 30 according to any one of claims 14 to 19, wherein the channel member is formed by an extrusion having constant transverse cross section so that the top wall, two 33 transversely spaced opposing sidewalls, and two longitudinally extending bottom wall portions are integrally formed.