Frame for access assembly
Patent Information
- Application Number
- PCT/GB2024/051716
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-07-02
- Publication Date
- 2026-01-08
Smart Images
Figure GB2024051716_08012026_PF_FP_ABST
Abstract
Description
[0001] FRAME FOR ACCESS ASSEMBLY
[0002] Field of the invention
[0003] The present invention relates to a frame for supporting an extendible cover, and a method of installing the same.
[0004] Background to the invention
[0005] Railways use a pair of rails, set a predetermined distance apart, on which wheels having vertical flanges are arranged to run. This provides an energy-efficient means of transport, with low rolling resistance. When conducting inspection, maintenance or repair of locomotives or rolling stock for a railway, it is common to provide an excavation beneath the pair of rails, allowing access to an underside of the locomotive or rolling stock, without removing the locomotive or rolling stock from the railway.
[0006] Access into the excavation is typically via steps or a ladder. When the excavation is not covered by a locomotive or rolling stock for inspection, maintenance or repair, the excavation is typically covered to reduce the risk of injury from falling into the excavation. It is known for the excavation to be covered by one or more wooden boards or planks. It is in this context that the present inventions have been devised. of the invention
[0007] In accordance with an aspect of the present invention, there is provided a frame configured to be supported between two parallel rails. The rails each have a rail portion extending upwardly and a lower flange portion extending inwardly towards the other rail from a base of the rail portion. The frame comprises: a first elongate member extending in a longitudinal direction; a second elongate member, parallel to the first elongate member; and at least one further elongate member, extending between the first elongate member and the second elongate member, and defining a lateral direction perpendicular to the longitudinal direction. The first and second elongate members are arranged to be parallel to the parallel rails, in use. The frame is configured to be extensible in the lateral direction, between a first configuration in which the frame is sized to be supported on the lower flange portion of both of the parallel rails, and a second configuration, different from the first configuration. The frame is configured to support an extendable cover, to allow an opening defined by the first elongate member, the second elongate member and the at least one further elongate member, to be selectively opened and closed by extension or retraction of the extendable cover, to thereby restrict or permit access through the frame. The frame is configured to resist movement away from the first configuration.
[0008] Thus, the frame can be used to allow the extendable cover to be used with parallel rails of different gauges (i.e. spaced apart by different distances). In other words, the same frame can be used for one set of parallel rails having a first spacing and a second set of parallel rails having a second spacing, different to the first spacing, because the frame is extensible in the lateral direction. It will be understood that in most areas, for railway lines, the rails are set at a common gauge for the whole area. However, different gauges exist around the world. By having an adjustable frame, this means that the same frame can be used in multiple parts of the world, even where the gauges are slightly different. Furthermore, by resisting movement away from the first configuration, the frame can be retained more easily in the first configuration, thereby allowing the frame to provide a secure support structure, even though the frame is extensible in the lateral direction.
[0009] Typically, the frame is capable of supporting the mass of a user on the extendable cover supported thereby. In this way, the frame, in combination with the extendable cover, is used to provide a working platform between parallel rails, such as to cover an opening that might otherwise be exposed and present a risk of fall. In other examples, the frame, in combination with the extendable cover, allows a better surface to be provided (e.g. flatter or at a similar height to the top of the rails) compared with the existing surface (e.g. railway sleepers and fixings, which can present trip hazards). Thus, it may be that the frame is configured to be at substantially the same height as the rails between which the frame is to be supported in use. Furthermore, it may be that the extendable cover, when installed, is also arranged to provide an outer surface substantially flush with the outer (upper) surface of the frame. Thus, the provision of the frame and extendable cover avoids trip hazards. The extendable cover, when installed, may further be arranged to provide an outer surface substantially flush with the outer (upper) surface of the rails between which the frame is to be supported.
[0010] The at least one further elongate member may be two further elongate members, a first further elongate member extending between a first end of the first and second elongate members and a second further elongate member extending between a second end of the first and second elongate members. Thus, a substantially rectangular opening may be defined by the first elongate member, the second elongate member, the first further elongate member and the second further elongate member.
[0011] The second configuration is typically one in which the frame is sized so as to be unable to be supported on the lower flange of both of the parallel rails. It may be that the frame has been contracted in the lateral direction so that the frame can no longer extend fully between the lower flange of both of the parallel rails. Alternatively, it may be that the frame has been expanded in the lateral direction so that the frame can no longer fit between the rail portion of both of the parallel rails. It will be understood that it may be that the second configuration would allow the frame to be used with a pair of parallel rails spaced differently. In other words, the first configuration may be suitable for supporting the frame on the lower flange portion of both of a first set of parallel rails and the second configuration may be suitable for supporting the frame on the lower flange portion of both of a second set of parallel rails.
[0012] It may be that the frame is configured to resist movement away from the first configuration by way of resisting movement of the first elongate member relative to the second elongate member. Alternatively or additionally, it may be that movement of one or more further components of the frame relative to one or more other components of the frame is resisted to thereby resist movement of the frame away from the first configuration. It will be understood that resist includes embodiments in which movement is possible but subject to some resistance (e.g. not freely moveable), as well as embodiments in which movement is entirely prevented, at least some of the time, such as by a fixing mechanism, like a latch, catch and / or locking pin connection. In some embodiments, it may be that the frame is configured to selectively resist movement away from the first configuration. In other words, there may be configurations of the frame in which movement towards and away from the first configuration is freely permitted, and other configurations in which movement is resisted.
[0013] The frame may further comprise at least two first rail contact members, arranged to be supported on the lower flange portion of a first rail of the two parallel rails, when the frame is in the first configuration; and at least two second rail contact members, arranged to be supported on the lower flange portion of a second rail of the two parallel rails, when the frame is in the first configuration. Thus, the frame can be configured specifically to contact the lower flange portions of the two rails using at least two contact members on each side of the frame, providing a stable platform having a total of at least four contact points with the rails (at least two with each rail).
[0014] The at least two first rail contact members and the at least two second rail contact members may be configured to support the frame so as to be substantially flush with an upper surface of the rail portion of the two parallel rails. It will be understood that different rails, having different heights between the lower flange portion of the rail and the upper surface of the rail portion, will typically require differences in the rail contact members to ensure the frame is at the appropriate height to avoid trip hazards. The at least two first rail contact members may be separate from the first elongate member and from the at least one further elongate member. At least one of the at least two first rail contact members may extend from the first elongate member. At least one of the at least two first rail contact members may extend from the at least one further elongate member. The at least two second rail contact members may be separate from the second elongate member and from the at least one further elongate member. At least one of the at least two second rail contact members may extend from the second elongate member. At least one of the at least two second rail contact members may extend from the at least one further elongate member. Where the frame comprises more than one further elongate member, it may be that first and second rail contact members extend at opposite ends of each further elongate member.
[0015] At least one of the at least two first rail contact members may be movably mounted to a further part of the frame. At least one of the at least two second rail contact members may be movably mounted to a further part of the frame. It may be that each of the rail contact members are movably mounted to a further part of the frame. In this way, the rail contact members that are movably mounted can move between an engaged position in which the contact members extend so as to retain the frame in position on the rail, between a bulbous region of the rail portion and the lower flange portion of the rail, and a disengaged position, inwardly of the engaged position, in which the contact members are arranged so as to allow the frame to be inserted and / or removed from between the rails, by allowing the contact members to move past the bulbous region of the rail portion during installation and / or removal of the frame.
[0016] It may be that when the rail contact members are in the engaged position, that the rail contact member may be in contact with the lower flange portion of the rail across a continuous portion of the rail contact member (rather than merely at one point on the rail contact member), thereby spreading the loading. Thus, the rail contact member is configured to be used with a given rail profile having a particular profile of the lower flange portion.
[0017] Typically, when the rail contact members are in the engaged position, there remains a space between the frame and the rail portion, allowing wheels (e.g. trains) to continue to move over the rails when the frame is covering the space between. The space is typically between 0.01 metres to 0.1 metres, such as between 0.015 metres to 0.06 metres on each lateral side of the frame.
[0018] At least one of the at least two first rail contact members may be slidably mounted to a further part of the frame. At least one of the at least two second rail contact members may be slidably mounted to a further part of the frame. Typically, the rail contact members that are slidably mounted are movable in a direction having at least a component in the lateral direction. Thus, the rail contact members that are slidably mounted to the further part of the frame can allow the frame to be resized. This can provide two benefits. Firstly, the frame can be resized to allow the same frame to be suitable to use with different gauges of rails, by sliding movement of the contact members. Secondly, the sliding movement of the contact members can allow the contact members to move between an engaged position in which the contact members extend so as to retain the frame in position on the rail, between a bulbous region of the rail portion and the lower flange portion of the rail, and a disengaged position, inwardly of the engaged position, in which the contact members are retracted so as to allow the frame to be inserted and / or removed from between the rails, by allowing the contact members to move past the bulbous region of the rail portion during installation and / or removal of the frame.
[0019] It will be understood that although the description hereinbefore refers to the engaged position and the disengaged position as being, respectively, positions in which the frame is retained in position between the rails, and in which the frame can be removed from between the rails, this also extends to an engaged position in which the removal of the frame from between the rails is possible but more difficult than in the disengaged position.
[0020] At least one of the first rail contact members and the second rail contact members may be configured to be rotatably connected to a further part of the frame. The at least one of the rail contact members that is rotatably connected to a further part of the frame may be rotatably connected about a rotation axis having at least a component perpendicular to the longitudinal direction and to the lateral direction. It may be that the rotational axis is perpendicular to the longitudinal direction and to the lateral direction. Thus, the rail contact members can be moved out of the way by rotation, to allow the frame to be (e.g. more easily) removed from between the rails.
[0021] The frame may be configured such that at least one of the first rail contact members and the second rail contact members are each resistant to movement relative to a further part of the frame to which the respective rail contact member is mounted. Thus, movement of the contact members between the engaged position and the disengaged position can be resisted, or even entirely prevented, at times. In some embodiments, the frame may be configured, in at least one configuration, to prevent movement of the at least one of the first and second rail contact members which can be movable in at least one other configuration.
[0022] Thus, it will be understood that multiple types of rail contact members may be provided on the same frame, some being slidably movable, and others rotatably movable. It may be that rail contact members mounted to the at least one further elongate member are slidably movable relative thereto, and rail contact members that are rotatably mounted are mounted to one of the first and second elongate members. Thus, a particularly elegant frame design is provided.
[0023] The at least one further elongate member may be extendable. In other words, a lateral extent of the frame can be changed by extension and / or retraction of the at least one further elongate member.
[0024] In some embodiments, it may be that the frame comprises both the at least one further elongate member being extendable, as well as movably mounted first and second rail contact members. Where this is provided, it may be that the at least one further elongate member being extendable allows for the lateral extent of the frame to be varied in order for the same frame to be usable with multiple rails, having different gauges, whilst the movably mounted first and second rail contact members allow the frame to be moved between the engaged and disengaged positions to allow for easy removal and installation of the frame in the disengaged position, and also to allow for the frame to be more difficult to remove in the engaged position. Thus, there is benefit to having two types of mechanisms by which the frame can be extendable in the lateral direction. Where the extendable cover is provided on the frame, it will be understood that this arrangement allows the frame to be removed from between the rails without first having to adjust a lateral extent of the extendable cover. Nevertheless, by the at least one further elongate member being extendable as well, this can allow for a wider range of extension for the frame, allowing the same frame to be used with a relatively wide range of different gauges of rails.
[0025] It may be that the at least one further elongate member is configured to be securable into a first extension position, in which movement away from the first extension position is resisted or even prevented. The at least one further elongate member may be releasable from the first extension position for movement away from the first extension position. It may be that the at least one further elongate member is configured to be securable into a second extension position, different from the first extension position, in which movement away from the second extension position is resisted or even prevented. The at least one further elongate member may be releasable from the second extension position for movement away from the second extension position. The at least one further elongate member may define one or more securing openings in movable parts thereof, through which a securing fastener can be inserted to secure the at least one further elongate member into the extension position and prevent movement away from the extension position. The at least one further elongate member may define a plurality of securing openings in at least one of the movable parts thereof. The securing openings may be defined on an upper surface of the movable parts.
[0026] The at least one further elongate member may be telescopically extendable. Where the frame comprises a plurality of further elongate members, such as two further elongate members, it may be that each of the further elongate members is telescopically extendable.
[0027] The at least one further elongate member may comprise an inner portion, having a first outer portion, telescopically extendable from a first end of the inner portion, and a second outer portion, telescopically extendable from a second end of the inner portion, opposite the first end.
[0028] The first and second outer portions may both have a first cross-sectional size, different to a cross-sectional size of the inner portion. The first and second outer portions of the at least one further elongate member may be arranged to at least partially enclose the inner portion. In other words, the inner portion may be telescopically received within the first and second outer portions. Thus, this arrangement may ensure that in all telescopically extendable positions of extension of the further elongate member, the outermost portions of the further elongate member (the first and second outer portions) are always exposed by the same amount, thereby avoiding a risk of trapping of fingers, clothing or other parts in the mechanism during reduction of the extent of the frame in the lateral direction. The first and second outer portions of the at least one further elongate member may be arranged to enclose the inner portion around the whole cross-section of the inner portion.
[0029] The first and second outer portions of the at least one further elongate member may be arranged to be at least partially enclosed by the inner portion. In other words, the outer portions may each be telescopically received within different ends of the inner portion. Thus, this arrangement provides a particularly good weight to strength ratio for the frame. Furthermore, the risk of trapping of fingers, clothing or other parts in the mechanism during extension of the extent of the frame in the lateral direction is avoided. The first and second outer portions of the at least one further elongate member may be arranged to be enclosed by the inner portion around the whole crosssection of the outer portions.
[0030] The at least one further elongate member may be secured directly to the first elongate member and the second elongate member. In other words, it may be that there is no intermediate fixing component preventing direct contact between the at least one further elongate member and the first and second elongate members. Thus, construction of the frame is simplified, with fewer parts than otherwise.
[0031] The first elongate member and the second elongate member may each be suspended from the at least one further elongate member. In other words, in use, the first elongate member and the second elongate member are suspended beneath or in shear from the at least one further elongate member. The first elongate member and the second elongate member may be affixed at a lower end of the at least one further elongate member. Thus, the frame is particularly simple to manufacture. Of course, other arrangements are also possible.
[0032] It may be that the frame is sized to have only a single extendable cover provided therein. To cover longer regions, it may be that multiple frames can be connected to each other. For example, the at least one further elongate member of a first frame may be connectable to the at least one further elongate member of a second frame by fasteners through one or more holes provided in each of the at least one further elongate members of the first and second frame.
[0033] The present disclosure extends to an access assembly, comprising the frame as described hereinbefore, and the extendable cover. The access assembly may comprise no more than one extendable cover for each frame, such as no more than one extendable cover.
[0034] The extendable cover may be formed from a plurality of cover elongate members, parallel to the at least one further elongate member, mutually connected by at least one pantograph unit extending therebetween, thereby allowing the cover to be extendable and retractable in the longitudinal direction. The at least one pantograph unit typically forms a trellis arrangement. It may be that at least one of the pantograph units is connected at a lower end of each of the plurality of cover elongate members. At least one other of the pantograph units may be connected at an upper end of each of the plurality of cover elongate members. There may be a plurality of pantograph units. It may be that there are more pantograph units connected at the lower end of each of the plurality of cover elongate members than the pantograph units connected at the upper end of each of the plurality of cover elongate members.
[0035] Each of the plurality of cover elongate members may be extensible in the lateral direction. Thus, a width of the extendable cover can be varied to be supported on the first and second elongate members in a plurality of extensible positions of the frame. It may be that each of the cover elongate members comprises an inner portion and at least one outer portion, extendable therefrom. Typically, each of the cover elongate members comprises the inner portion and a first outer portion telescopically extendable from a first end of the inner portion and a second outer portion telescopically extendable from a second end of the inner portion. Typically, a cross-sectional size of the first and second outer portions is identical, and different (e.g. less than) a cross- sectional size of the inner portion. It may be that the cross-section sizes of the inner portion and outer portions making up the at least one further elongate member are identical to the cross-sectional sizes making up the inner portion and the first and second outer portions of the cover elongate members. Thus, manufacturing of the frame can be done using cross-sections already required to manufacture the extendable cover.
[0036] The access assembly and / or the frame may each be configured to support a user thereon. Thus, the access assembly and / or the frame may be sufficiently strong for a user to be supported thereon. It may be that the access assembly and / or the frame may need to be sufficiently rigid to support a user standing and working therefrom without significant flex of the structure.
[0037] The present disclosure extends to a method of installing the access assembly described hereinbefore, between a pair of rails. The method comprises: providing the frame between the pair of rails, the frame being supported on the lower flange portion of each of the pair of rails; providing the extendable cover within the frame, the extendable cover being supported on the first and second elongate members of the frame; and securing the frame and the extendable cover in the first configuration.
[0038] Thus, by securing the frame in the first configuration, the frame can resist movement away from the first configuration, thereby ensuring a stable access assembly is provided between the pair of rails.
[0039] It may be that the extendable cover is provided within the frame before the frame is provided between the pair of rails. In other examples, it may be that the extendable cover is provided within the frame after the frame is provided between the pair of rails.
[0040] The present disclosure extends to a method of removing the access assembly as described hereinbefore, having been installed between a pair of rails, using the method as described hereinbefore. The method further comprises: releasing the frame from the first configuration to allow movement away from the first configuration and thereby allow the access assembly to be removed from the pair of rails with the extendable cover still within the frame.
[0041] Thus, the access assembly can be conveniently removed from the rails efficiently.
[0042] In other examples, the method comprises removing the extendable cover from within the frame, prior to removing the frame from the pair of rails. Removing the extendable cover from within the frame comprises disengaging one or more fastening means securing the extendable cover to the frame. The fastening means may comprise a plurality of resiliently deformable locking pin arrangements each provided on one of the extendable cover and the frame (e.g. the extendable cover), each extending within a corresponding opening provided within an other of the extendable cover and the frame (e.g. the frame). When the or each of the resiliently deformable locking pin arrangements are removed from the corresponding openings, the extendable cover is no longer retained within the frame and can be removed. Thus, by removing the extendable cover separately to the frame, this means that the frame can be retained in place, whilst the frame can be moved to another opening; it also reduced the mass of components to be moved at the same time, which makes removal of the access assembly more manageable. Subsequent to removal of the extendable cover from the frame, the method may comprise releasing the frame from the first configuration to allow movement away from the first configuration and thereby allow the frame to be removed from the pair of rails.
[0043] Releasing the frame from the first configuration may comprise movement (e.g. sliding and / or rotational movement) of one or more of the rail contact members.
[0044] It will be understood that by the extendable cover being described as being within the frame, this means that the extendable cover is supported by the first and second elongate members of the frame.
[0045] It may be that the parallel rails described hereinbefore are rails of a railway line. The frame may be formed from metal. Specifically, at least the first elongate member, the second elongate member and the at least one further elongate member may be formed from metal. Other materials are possible.
[0046] The first and second elongate members may be formed from an angle cross-section, the angle having a lower portion for supporting the extendable cover thereon and a vertical portion extending upwardly from the lower portion to prevent lateral movement of the extendable cover out of the frame. of the Drawings
[0047] An example embodiment of the present invention will now be illustrated with reference to the following Figures in which:
[0048] Figure 1a shows a frame according to an example of an aspect of the present invention, in an engaged position;
[0049] Figure 1 b shows the frame of Figure 1a, in an disengaged position;
[0050] Figure 2 shows the frame of Figures 1a, 1 b, installed between two rails;
[0051] Figure 3 shows a cross-section through a further elongate member of the frame of Figures 1a, 1 b, taken vertically in a lateral direction;
[0052] Figure 4 shows the frame of Figures 1a, 1 b, having the extendable cover installed therein;
[0053] Figure 5 shows a portion of a frame according to another example of an aspect of the present invention;
[0054] Figure 6 is a flow-chart illustrating a method according to an aspect of the present invention; and
[0055] Figure 7 is a flow-chart illustrating a method according to another aspect of the present invention.
[0056] Detailed Description of an Example Embodiment
[0057] Figure 1a shows a frame according to an example of an aspect of the present invention. The frame 100 comprises a first elongate member 102 and a second elongate member 104, each extending mutually parallel and defining a longitudinal direction. The first and second elongate members 102, 104 are each formed from metal angle sections. The angle section profile of the second elongate member 104 is best illustrated in Figures 2 and 3 described hereinafter. A support surface 106 for the first elongate member 102 provides a surface on which an extendable cover (as shown in Figure 4 hereinafter) can rest within the frame 100. The frame 100 further comprises a first further elongate member 108 extending between the first elongate member 102 and the second elongate member 104 at a distal end thereof, and a second further elongate member 110, extending between the first elongate member 102 and the second elongate member 104 at a proximal end thereof. The first and second further elongate members 108, 110 each extend in a lateral direction, perpendicular to the longitudinal direction defined by the first and second elongate members. Thus, the frame provides a substantially rectangular open central region O. As best illustrated by Figure 4 hereinafter, the open central region O can be closed by installation of the extendable cover described further with reference to Figure 4 hereinafter. The first and second further elongate members 108, 110 are formed from a first box section 112 connected to the first elongate member 102, a second box section 114 telescopically extendable relative to the first box section 112 and a third box section 116 telescopically extendable relative to the second box section 114 and connected to the second elongate member 104. In this example, the second box section 114 is an inner box section and is telescopically received within the first box section 112 and the third box section 116. In this way, the frame 100 can be extensible in the lateral direction by movement of the first elongate member 102 relative to the second elongate member 104 via telescopic extension of the box sections 112, 114, 116 of the first and second further elongate members 108, 110. As best described with reference to Figure 3 hereinafter, the separation of the first elongate member 102 relative to the second elongate member 104 can be fixed by a locking mechanism of the first and second further elongate members 108, 110.
[0058] The frame 100 further comprises rail contact members 118, 120, 122, 124, 126, 128, configured to support the frame 100 on a lower flange portion of two rails, as best illustrated in Figure 2. Figures 1a and 2 show the rail contact members 118, 120, 122, 124, 126, 128 when the frame 100 is in an engaged position in which the rail contact members will contact the rails as shown and described with reference to Figure 2. In this example, the longitudinal side of the frame 100 associated with the first elongate member 102 comprises three rail contact members 118, 126, 120, being a first rail contact member 118 arranged at a first end of the first elongate member 102, slidably mounted to an end of the second further elongate member 110, a second rail contact member 120 arranged at a second end of the first elongate member 102, slidably mounted to an end of the first further elongate member 108, and a first central rail contact member 126 arranged between the first end and the second end of the first elongate member 102 and rotatably mounted to the first elongate member 102 about a vertical axis of rotation. The longitudinal side of the frame 100 associated with the second elongate member 104 comprises three rail contact members 122, 128, 124, being a third rail contact member 122 arranged at a second end of the second elongate member 104, slidably mounted to an end of the first further elongate member 108, a fourth rail contact member 124 arranged at a first end of the second elongate member 104, slidably mounted to an end of the second further elongate member 110, and a second central rail contact member 128 arranged between the first end and the second end of the second elongate member 104 and rotatably mounted to the second elongate member 104 about a vertical axis of rotation.
[0059] The first, second, third and fourth rail contact members 118, 120, 122, 124 are each slidably mounted in a lateral direction, such that the first, second, third and fourth rail contact members 118, 120, 122, 124 can be moved between an engaged position and a disengaged position. Figure 1a shows the first, second, third and fourth rail contact members 118, 120, 122, 124 in the engaged position. Figure 1 b shows the same frame 100 as in Figure 1a, but with the first, second, third and fourth rail contact members 118, 120, 122, 124 in the disengaged position.
[0060] The first central rail contact member 126 and the second central rail contact member 128 are each rotatably mounted to the first and second elongate members 102, 104, respectively, about an axis transverse to the longitudinal direction of the first and second elongate members 102, 104, and transverse to a longitudinal direction of the further elongate members 108, 110. In other words, the axis is substantially vertical. In Figure 1a, the first and second central rail contact members 126, 128 are each rotated into an engaged position, and it would be difficult if not impossible to lift the frame 100 free of the rails shown in Figure 2. In Figure 1 b, the first and second central rail contact members 126, 128 are each rotated into a disengaged position, and the frame 100 could be easily removed from the rails that are shown in Figure 2.
[0061] As shown in Figure 1a, the rail contact members 118, 120, 122, 124, 126, 128 are each shown in an engaged position, each extending further from the rest of the frame 100, in a lateral direction, than in a disengaged position, as shown in Figure 1b.
[0062] The frame 100 is extensible in the lateral direction, both by movement of the rail contact members 118, 120, 122, 124, 126, 128 and by telescopic extension of the first and second further elongate members 108, 110.
[0063] Figure 2 shows the frame of Figure 1 , installed between two rails. The rails 210, 220 comprise a first rail 210 extending in the longitudinal direction of the frame 100 and a second rail 220, parallel to the first rail 210 and extending in the longitudinal direction of the frame 100. The first rail 210 comprises a lower flange portion 212 and a rail portion 214. The lower flange portion 212 extends from a base of the rail portion 214 in a substantially horizontal direction. The rail portion 214 extends substantially vertically upwards from the lower flange portion 212 and comprises a bulbous region at an upper end thereof. In other words, there exists an overhang below the bulbous region of the rail portion 214. The second rail 220 is substantially identical in shape to the first rail 210 and therefore also comprises a lower flange portion 222 and a rail portion 224, similar to those described with reference to the first rail 210.
[0064] In this way, as seen in Figure 2, the first rail contact member 118 (and the second rail contact member 120 and the first central rail contact member 126 not labelled in Figure 2), when in the engaged position as shown in Figure 2, are unable to pass by the bulbous region of the rail portion 214 of the first rail 210. Similarly, the fourth rail contact member 124 (and the third rail contact member 122 and the second central rail contact member 128), when in the engaged position as shown in Figure 2, are unable to pass by the bulbous region of the rail portion 224 of the second rail 220. Thus, removal of the frame 100 from the rails 210, 220 when the rail contact members are in the engaged position is prevented. The first rail contact member 118 has defined therein a first horizontal slot 130 and a second horizontal slot 132, for engagement with pins connected to the first box section 112 of the second further elongate member 110. Thus, the first rail contact member 118 can be slid horizontally by movement of the pins within the horizontal slots 130, 132. The pins can be selectively tightened and loosened to clamp the first rail contact member 118 against the first box section 112 and thereby fix the extension of the first rail contact member 118 relative to the first box section 112, or release the first rail contact member 118 for sliding movement relative to the first box section 112. It will be understood that a similar arrangement exists for the second rail contact member 120 in cooperation with the first box section 112 of the first further elongate member 108. Similarly, the fourth rail contact member 124 has defined therein horizontal slots 134, 136 for engagement with pins connected to the third box section 116 of the second further elongate member 110, which facilitate a similar function on the other side of the frame 100. It will also be understood that a similar arrangement exists for the third rail contact member 122 in cooperation with the third box section 116 of the second further elongate member 110.
[0065] Figure 3 shows a cross-section through a further elongate member of the frame of Figure 1 , taken vertically in a lateral direction. The cross-section cuts through the first further elongate member 108, and shows the third box section 116 with the second box section 114 telescopically received therein. The cross-section also cuts through the second elongate member 104, showing the angle-section, having a vertical portion 138 and a horizontal portion 140. As described with reference to Figure 4 hereinafter, the extendable cover is supported on the horizontal portion 140 of each of the first and second elongate members 102, 104. The second elongate member 104 is secured to the first further elongate member 108, specifically to the third box section 116 of the first further elongate member 108 by being suspended therefrom. Two fasteners 105a, 105b are used to affix the horizontal portion 140 of the second elongate member 104 to the third box section 116 of the first further elongate member 108.
[0066] Figure 3 also shows the third rail contact member 122, slidably mounted to the third box section 116 of the second further elongate member 110 as described hereinbefore. In Figure 3, the pins 142, 144 can be seen, which engage with the horizontal slots in the third rail contact member 122 (not visible in Figure 3). Securing fasteners 146, 148 are also illustrated which fixedly secure the third box section 116 relative to the second box section 114, preventing further sliding movement when engaged. In this example, the securing fasteners 146, 148 are screws and are arranged to be inserted during installation, to commission the frame 100 for a particular gauge of rail separation. It will be understood that the securing fasteners 146, 148 are self-tapping screws in this example, configured to screw into the second box section 114 through pre-formed openings in the third box section 116. Thus, the same pre-commissioned frame 100 can be used for a range of different rail gauges. Once the frame 100 has been commissioned by inserting the securing fasteners 146, 148 in the required locations, the frame 100 is only suitable for use with one gauge of rail separation. Other examples may allow the securing fasteners to be removed and repositioned to reconfigure the frame for other rail gauges multiple times.
[0067] Although Figure 3 only shows one of the four corners of the frame 100, it will be understood that a similar arrangement is provided at each of the other three corners of the frame 100.
[0068] Figure 4 shows the frame of Figure 1 , having the extendable cover installed therein. The frame 100 is as described hereinbefore, with the provision of the extendable cover 300 therein. When combined in this way, the assembly of the frame 100 with the extendable cover 300 may be referred to as an access assembly. In particular, the extendable cover 300 comprises a plurality of cover elongate members 302a, 302b, 302c (for brevity, only three are labelled in Figure 4, though Figure 4 shows 24 cover elongate members). Each of the plurality of cover elongate members 302a, 302b, 302c are parallel to each other and to the further elongate members 108, 110 of the frame 100. The extendable cover 300 further comprises an upper pantograph unit 304, and three lower pantograph units 306, 308, 310. Each pantograph unit 304, 306, 308, 310 is connected to each of the plurality of cover elongate members to form a trellis arrangement and allow the extendable cover 300 to extend between an extended configuration in which the opening O in the frame 100 is closed (as shown in Figure 4) and an open configuration in which the extendable cover 300 is slid to one end of the frame 100 and passage of a person or goods through the opening O in the frame 100 is possible. Each of the cover elongate members 302a, 302b, 302c is extensible in a lateral direction, such that the extendable cover 300 can also be arranged to fit within the frame 100 and cover the entire opening O in the lateral direction in multiple different extension positions of the further elongate members 108, 110. In particular, each of the cover elongate members 302a, 302b, 302c comprises an inner portion and a first outer portion telescopically extendable from a first end of the inner portion and a second outer portion telescopically extendable from a second end of the inner portion. A cross-sectional size of the first and second outer portions is identical, and less than a cross-sectional size of the inner portion. The cross-section sizes of the inner portion and outer portions making up the inner portion and the first and second outer portions of the cover elongate members 302a, 302b, 302c is identical to the cross-sectional size of the first, second and third box sections 112, 114, 116 of the further elongate members 108, 110.
[0069] Figure 5 shows a portion of a frame according to another example of an aspect of the present invention. The frame 100a is substantially similar to the frame 100 described hereinbefore apart from the hereinafter noted differences. In the first further elongate member 108a of the frame 100a, the first box section 112a and the third box section 116a each have a cross-sectional size smaller than the second box section 114a and therefore are telescopically received within the opposite ends of the second box section 114a. Additionally, the first and second elongate members 102a, 104a are each secured to the first further elongate member 108a via fixing brackets 150, 152. The fixing brackets 150, 152 are welded to the first and second elongate members 102a, 104a respectively, and secured by fixing bolts to the first box section 112a and the third box section 116a respectively of the first further elongate member 108a. It will be understood that the configuration of the second further elongate member and the connections between the second further elongate member and the first and second elongate members 102a, 104a is substantially similar as described with reference to the first further elongate member 108a.
[0070] Figure 6 is a flow-chart illustrating a method according to an aspect of the present invention. The method 400 is a method of installing the access assembly, comprising the frame 100 and the extendable cover 300 described hereinbefore, between a pair of rails 210, 220. The method 400 comprises providing 410 the frame 100 between the pair of rails 210, 220. Providing 410 the frame 100 between the pair of rails 210, 220 comprises supporting the frame 100 on the lower flange 212, 222 of each of the pair of rails 210, 220. The method 400 further comprises providing 420 the extendable cover 300 within the frame 100. The method 400 further comprises securing 430 the frame 100 in the first configuration and securing the extendable cover 300 in the first configuration. In this way, the access assembly cannot easily be removed from the pair of rails 210, 220 when the frame 100 and the extendable cover 300 are both secured in the first configuration. The first configuration is where the frame 100 is sized to be supported on the lower flange portion 212, 222 of the pair of rails 210, 220.
[0071] It will be understood that the extendable cover 300 can be provided within the frame 100 at substantially any step of the method, before or after any of the other steps described.
[0072] Figure 7 is a flow-chart illustrating a method according to another aspect of the present invention. The method 500 is a method of removing the access assembly, previously having been installed between the pair of rails as described with reference to Figure 6 hereinbefore. The method 500 comprises releasing 510 the frame 100 from the first configuration. In this way, movement of the frame is permitted away from the first configuration, allowing the access assembly to be removed from the pair of rails 210, 220. Typically, the extendable cover 300 remains within the frame 100 when the frame 100 is removed from the pair of rails 210, 220.
[0073] In summary, there is provided a frame (100) configured to be supported between two parallel rails (210, 220), the rails each having a rail portion (214, 224) extending upwardly and a lower flange portion (212, 222) extending inwardly towards the other rail from a base of the rail portion. The frame (100) comprises: a first elongate member (102) extending in a longitudinal direction; a second elongate member (104), parallel to the first elongate member; and at least one further elongate member (108, 110), extending between the first elongate member (102) and the second elongate member (104), and defining a lateral direction perpendicular to the longitudinal direction. The first and second elongate members are arranged to be parallel to the parallel rails, in use. The frame is configured to be extensible in the lateral direction, between a first configuration in which the frame is sized to be supported on the lower flange portion of both of the parallel rails, and a second configuration, different from the first configuration. The frame is configured to support an extendable cover (300), to allow an opening defined by the first elongate member, the second elongate member and the at least one further elongate member, to be selectively opened and closed by extension or retraction of the extendable cover, to thereby restrict or permit access through the frame. The frame is configured to resist movement away from the first configuration.
[0074] Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of them mean “including but not limited to”, and they are not intended to and do not exclude other components, integers, or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.
[0075] Features, integers, characteristics, or groups described in conjunction with a particular aspect, embodiment, or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and / or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.
Claims
Claims1. A frame configured to be supported between two parallel rails, the rails each having a rail portion extending upwardly and a lower flange portion extending inwardly towards the other rail from a base of the rail portion, and the frame comprising: a first elongate member extending in a longitudinal direction; a second elongate member, parallel to the first elongate member; and at least one further elongate member, extending between the first elongate member and the second elongate member, and defining a lateral direction perpendicular to the longitudinal direction, wherein the first and second elongate members are arranged to be parallel to the parallel rails, in use, wherein the frame is configured to be extensible in the lateral direction, between a first configuration in which the frame is sized to be supported on the lower flange portion of both of the parallel rails, and a second configuration, different from the first configuration, wherein the frame is configured to support an extendable cover, to allow an opening defined by the first elongate member, the second elongate member and the at least one further elongate member, to be selectively opened and closed by extension or retraction of the extendable cover, to thereby restrict or permit access through the frame, and wherein the frame is configured to resist movement away from the first configuration.
2. The frame of claim 1 , further comprising: at least two first rail contact members, arranged to be supported on the lower flange portion of a first rail of the two parallel rails, when the frame is in the first configuration; and at least two second rail contact members, arranged to be supported on the lower flange portion of a second rail of the two parallel rails, when the frame is in the first configuration.
3. The frame of claim 2, wherein at least one of the at least two first rail contact members and the at least two second rail contact members is slidably mounted to a further part of the frame.
4. The frame of claim 2 or claim 3, wherein at least one of the first rail contact members and the second rail contact members is configured to be rotatably connected to a further part of the frame.
5. The frame of any of claims 2 to 4, wherein the frame is configured such that at least one of the first rail contact members and the second rail contact members are each resistant to movement relative to a further part of the frame to which the respective rail contact member is mounted.
6. The frame of any preceding claim, wherein the at least one further elongate member is extendable.
7. The frame of claim 5, wherein the at least one further elongate member comprises an inner portion, having a first outer portion, telescopically extendable from a first end of the inner portion, and a second outer portion, telescopically extendable from a second end of the inner portion, opposite the first end.
8. The frame of claim 6, wherein the first and second outer portions both have a first cross-sectional size, different to a cross-sectional size of the inner portion.
9. The frame of claim 7, wherein the first and second outer portions of the at least one further elongate member are arranged to at least partially enclose the inner portion.
10. The frame of claim 7, wherein the first and second outer portions of the at least one further elongate member are arranged to be at least partially enclosed by the inner portion.
11. The frame of any preceding claim, wherein the at least one further elongate member is secured directly to the first elongate member and the second elongate member.
12. The frame of any preceding claim, wherein the first elongate member and the second elongate member are each suspended from the at least one further elongate member.
13. An access assembly, comprising the frame of any preceding claim, and the extendable cover.
14. The frame of any of claims 1 to 12, or the access assembly of claim 13, wherein the extendable cover is formed from a plurality of cover elongate members, parallel to the at least one further elongate member, mutually connected by at least one pantograph unit extending therebetween, thereby allowing the cover to be extendable and retractable in the longitudinal direction.
15. The frame or the access assembly of claim 14, wherein each of the plurality of cover elongate members is extensible in the lateral direction.
16. The frame or the access assembly of any preceding claim, wherein the access assembly and / or the frame are each configured to support a user thereon.
17. A method of installing the access assembly of any of claims 14 to 16, between a pair of rails, the method comprising: providing the frame between the pair of rails, the frame being supported on the lower flange portion of each of the pair of rails; providing the extendable cover within the frame, the extendable cover being supported on the first and second elongate members of the frame; and securing the frame and the extendable cover in the first configuration.
18. A method of removing the access assembly of any of claims 14 to 16, having been installed between a pair of rails, using the method of claim 17, the method further comprising:releasing the frame from the first configuration to allow movement away from the first configuration and thereby allow the access assembly to be removed from the pair of rails with the extendable cover still within the frame.