AU2005200785A1 - Collapsible Stairway - Google Patents

Description

P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION Invention Title: Collapsible Stairway The following statement is a full description of this invention, including the best method of performing it known to me: COLLAPSIBLE STAIRWAY 14 FIELD OF THE INVENTION SThis invention relates to a collapsible stairway. The invention particularly relates to a I stairway which is collapsible from an in use condition to a storage condition.

BACKGROUND OF THE INVENTION 00 There are many situations where access to an elevated area or platform is required where there are no permanent ascending means available, such as stairs, a ladder or an Selevator. Such environments exist, for example, on truck trays, loading bays, stages, etc, where it is impractical or inconvenient to provide permanent ascending means.

While portable steps or a ladder can be placed into position in order to gain access, these may not always be available and, in the case of a truck tray, may require that the steps or ladder be stored on the truck tray when not in use, thereby restricting the available space. Furthermore, such temporary solutions are often unstable and can slip or collapse, thereby undermining the safety of the user.

It is therefore an object of the present invention to provide a collapsible stairway which overcomes or at least alleviates one or more of the disadvantages noted above.

SUMMARY OF THE INVENTION According to the present invention, there is provided a stairway including: at least one platform member; and support means for supporting said at least one platform member in an orientation suitable for supporting a user's foot; wherein said stairway is collapsible from an in use condition to a storage condition.

The invention also provides a collapsible handrail for a collapsible stairway.

In addition, the invention provides a restraining cradle and rest for a collapsible stairway.

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DESCRIPTION OF PREFERRED EMBODIMENTS 14 Accordingly, the invention provides a stable collapsible stairway which can be Sunfolded into its in use condition when access to the raised area or platform is desired and then collapsed into its storage condition when it is no longer needed.

In one embodiment, the stairway is positioned out of the way when in the storage 00 condition so as to not interfere with the normal use of the elevated area or platform.

In other embodiments, the stairway of the invention includes features to protect the V) safety of the user.

NI The stairway of the invention is manipulable between a storage condition and an in use condition. Typically, in the storage condition the stairway is "collapsed" with all the constituent parts in a similar orientation such that it occupies a relatively small amount of space. In the in use condition, the component parts of the stairway are extended out into their "in use" orientation.

The stairway includes at least one platform member. The at least one platform member performs the function of supporting a user of the stairway.

Typically the at least one platform member is sized and shaped to accommodate a user's foot. The exact number of platform members required for the stairway will of course depend on the environment in which it is to be used. Where the stairway is to be provided on or under a truck tray, typically at least two platform members will be necessary. In other applications, such as in factories, the stairway will include more steps, such as up to ten.

The stairway further includes support means for supporting the at least one platform member in a useable orientation, which is typically substantially horizontal. The support means is preferably mountable in close association with the elevated area or platform to which access is desired, such as a truck tray.

More preferably, the support means is attachable under the elevated area so that it does not obstruct the normal use of the raised area.

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SThe support means preferably includes at least one elongate moveable support member having said at least one platform member attached thereto at respective spaced intervals along its length. More preferably, the at least one moveable support member is mounted for pivotable movement relative to said elevated surface.

C 5 Typically the at least one elongate moveable support member is pivotable from a first,

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raised position to a second, lowered position. The first, raised position of said support Smember usually corresponds with the storage condition of said stairway and the 00oO second, lowered position usually corresponds with the in use condition. The support member is usually substantially horizontal when in its raised position and is usually kn 10 inclined to the horizontal when in its lowered position.

NI It is preferred that the support means includes two moveable elongate support members each of which is disposed at a respective lateral side of each or the platform member. Preferably, each elongate support member is mounted for pivotable movement, as described above.

Preferably, the or each moveable elongate support member is a unitary member so that rigidity of the member is maximised.

Preferably, the support means enables the stairway to be retractable so as to be at least partly, and preferably fully, accommodated on, under, adjacent or within said platform, so that no or a minimum portion of the stairway extends beyond the platform periphery. In this embodiment, the support means further comprises at least one fixed support member which is mounted or mountable on, under, adjacent or within said platform. The moveable support members cooperate with the or each fixed support member to be retracted and retained in its retracted position. This may be achieved by folding the moveable support members and securing the folded members to the fixed member/s, or by sliding the moveable support members in the fixed member/s, or by both folding and sliding the moveable members, or by rotating the moveable support members relative to the fixed support member/s.

In one preferred embodiment each moveable support member is slidably received in the fixed support member. This mode is advantageous because the depth of the collapsed stairway is approximately equivalent to the width of the moveable support members, resulting in more compact storage. More preferably, each fixed support member includes a track sized to receive a corresponding moveable support member.

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SEach track is preferably mounted below the platform and is positioned such that, with the moveable support member received therein, the stairway can be wholly positioned and stored below the platform.

Preferably, each moveable support member is provided with a guiding support member to assist in guiding the moveable support member into its corresponding 00 track. The guiding support member may comprise an elongate member sized to be Oslidably receivable in the track. In this embodiment, each moveable support member (Ni is preferably pivotably mounted to its corresponding guiding support member. Each guiding support member may be provided with a movement facilitator, such as one or N more rollers, in order to facilitate its movement within the fixed support member.

Preferably, the support means further includes stop means to limit the extent of travel of the guiding support member in the fixed support member.

In another preferred embodiment, the moving support member/s are rotatable in a substantially horizontal plane relative to the fixed support member/s.

This embodiment is particularly appropriate for use under a semi-trailer truck tray which has an undercarriage configuration unsuitable to accommodate a sliding retraction mechanism. In this embodiment, the collapsed stairway is rotatable about a rotational axis, preferably about a substantially vertical rotational axis, preferably by around 90', in order to retract the stairway into its stored condition.

Typically, the stairway is rotatable in an essentially horizontal plane. Typically, the stairway is rotatable so that it is essentially completely received under the elevated area. In this embodiment, the fixed support member typically comprises a mounting member, preferably a mounting plate, which is mountable underneath the elevated surface. The stairway is then rotatably mounted on the plate, typically about a pin or a rod. The stairway and the pin may be fixed relative to each other and rotate as a unit relative to said mounting plate. However, preferably, the pin is fixed relative to the mounting member and the stairway is free to rotate about the pin.

The embodiment having the rotatable retraction mechanism is particularly appropriate for use under the tray of a semi-trailer truck, which has an undercarriage configuration unsuitable to accommodate a sliding retraction mechanism.

SIn this application, the stairway preferably extends laterally of the truck tray. It may

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Sbe then collapsed and rotated about 900 in the horizontal plane into its stored (-i condition. When retracted into its stored condition, the moveable support members extend longitudinally underneath the truck tray.

Ni 5 Accordingly, in order to retract the stairway from its in use condition into its stored condition, the moveable support members are pivoted upwards so as to collapse the 00 stairway, and the collapsed stairway is then rotated about the rotational axis into its Ostored condition. Typically this requires about 90' of rotation or by whatever amount N is necessary to retract the stairway at least partially below the platform.

The stairway is preferably mounted to the fixed support member via a rotatable mounting means. The rotatable mounting means may comprise any suitably located upper component of the stairway. Preferably, the rotatable mounting means comprises at least part of an upper supporting structure of the stairway, from which supporting structure the moveable support member/s are pivotably attached. More preferably, the rotatable mounting means comprises a bar or a plate extending widthwise across said upper supporting structure.

This embodiment also preferably includes a mounting support for supporting the rotatable mounting means. Preferably, the mounting support comprises a plate which is fixed relative to the rotatable mounting means and whose upper surface provides support for the rotatable mounting means during its rotation. As the entire weight of the stairway is typically depending from the rotatable mounting means, the mounting support should be strong enough to adequately support that weight. Preferably, the mounting support is shaped and sized so as to support a substantially constant proportion of the rotatable mounting means throughout the extent of its rotation. The mounting support may therefore be of substantially circular configuration with its centre coinciding with the axis of rotation. Preferably, the pin extends through the rotatable mounting means to the mounting support. More preferably, the pin is fixed relative to the mounting support. More preferably, the fixed support member, pin and mounting support are fixed relative to each other and the rotatable mounting means is separately rotatable in relation to them.

knAs previously stated, each platform member is supported by the support means in an 0 orientation suitable for supporting a user's foot. Usually such an orientation will be substantially horizontal. Each platform member is typically connected to the at least one moveable elongate support member. Preferably, each platform member is C 5 connected for pivotable movement to at least one moveable support member. More preferably, each lateral side of the platform member is pivotably connected to a Srespective elongate support member.

00oO Advantageously, the stairway further includes orientating means to ensure that each C platform member is positioned in the desired orientation (usually substantially horizontal). The orientating means, if present, typically cooperates with the connection/s to the elongate support member/s to maintain the platform members in the desired orientation with respect to horizontal, as the stairway is being unfolded.

The orientating means includes attachment means, for attachment to each platform member. An example of a suitable attachment means is a hinge. The attachment means of each platform member are all preferably interconnected by a connecting member, such as a bar or rod. The connecting member is preferably mounted for hinged or pivotable movement so as to enable its movement to track the pivotable movement of the moveable support members. This may suitably be achieved, for example, where the connecting means is hingedly or rotatably connected to a shaft mounted on one or both guiding support members.

With the stairway in its collapsed condition, the platform members are essentially aligned with the elongate support members and with each other.

Preferably, the platform members are all within the same horizontal plane. As the elongate support members are pivoted downwardly, the connecting member tracks the movement of the elongate support members by virtue of the inter connection therebetween via the platform members. Typically the connecting member remains parallel with the elongate support members during this movement. The downward movement causes the platform members to become vertically spaced from each other.

During this downward, rotational movement, the plane defined by the connection between the elongate support member/s and each platform member and the respective attachment means of each platform member remains in a substantially constant

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t orientation relative to the horizontal. That orientation is typically substantially parallel to the horizontal. This substantial horizontal alignment ensures that each N platform member maintains a substantially horizontal orientation throughout the Sunfolding of the stairway into its in use condition.

(-i (N 5 In some embodiments, the movement of the support members from the stored to the in use condition is assisted hydraulically, pneumatically or mechanically. Such 00oO assistance is desirable where the weight of the stairway is high and possibly too heavy to be lowered manually.

t The collapsible stairway preferably further includes a handle means to assist in O 10 gripping the stairway as it is moved between the stored and in use conditions. In the embodiment containing two elongate support members, preferably, the handle means comprises a tie bar joining the two support members below the platform members.

In a particularly preferred embodiment, the collapsible stairway includes a positioning means for positioning the or each elongate support member at an angle to the horizontal within a predetermined range, nominally defined as from a* to 13. This embodiment finds particular application for enabling the stairway to comply with relevant safety standards when in use. International safety standards stipulate that for safe usage, a stairway should make an angle to the horizontal within a certain range.

The corresponding Australian Standard AS 1657 stipulates an angle range of between 26.50 and 45' to horizontal. The positioning means enables the stairway to operate within this range of angles. In practice, it has been found that for a collapsible stairway a minimum angle of 35' is desirable.

The positioning means comprises a first positioning member, including a projection, which is receivable within a second positioning member, comprising a recess or a slot. One positioning member is provided on a moveable support member (hereinafter referred to as the moveable positioning member) and the other member is fixed horizontally relative to said one positioning member (hereinafter referred to as the fixed positioning member). The second member is orientated such that with the first member received therein in a first location, the moveable support member makes the angle a 0 to the horizontal and with the first member received therein at a second location, the moveable support member makes the angle 3 to the horizontal. It is t preferred that the projection is received snugly within the recess or slot of the second member, so as to limit relative movement therebetween. It is also preferred that said first and second locations correspond with the first and second ends, respectively, of the second positioning member.

Accordingly, when the stairway is in its collapsed, stored condition, the projection is not received in the second member. As the stairway is unfolded from its stored 00oO condition, the relative movement between the moveable and fixed positioning members causes the projection to enter the first position of the recess or slot of the (i second positioning member. In this position, the moveable supporting member makes an angle of a 0 to the horizontal. With further unfolding of the stairway, the projection N, travels further into the second positioning member, until it reaches the second end therein. In this position, the moveable supporting member/s makes an angle of 3 to the horizontal. Preferably, the projection is prevented from moving beyond the second end of the second positioning member, such that the moveable supporting member cannot exceed an angle of 30 to the horizontal.

The first positioning member may comprise an elongate element, extending from a moveable support member, having the projection thereon.

Preferably the projection projects laterally of the elongate element. The elongate element is preferably pivotably connected to the moveable support member.

Preferably, the second positioning member comprises a downwardly extending inclined slot which is sized to snugly receive the projection. The slot preferably has one open end, through which the projection is received and one closed end, which limits the movement of the projection therein.

In another particularly preferred embodiment, the stairway includes a collapsible hand supporting means. Preferably, the hand supporting means comprises a handrail assembly including at least one strut, more preferably, two or more struts, each of which supports a handrail bar. The two struts are each rotatably connected at one end thereof to a moveable support member and at the other end thereof to the handrail bar.

In this embodiment, the stairway also preferably includes a handrail raising means which operates to raise the handrail assembly from a collapsed position to a raised t position simultaneously with the unfolding of the stairway from its stored condition to its in use condition.

(-i SPreferably, the handrail is raised to a height conforming to international safety standards. The handrail raising means includes a ramped surface engageable by an actuating means provided on the handrail assembly. The ramped surface may comprise an inner wall of an inclined slot or recess. The actuating means typically 00 comprises a lug or a pin. Preferably, the lug is provided on, and extends laterally of, one of the two struts.

With the stairway in its stored condition the lug engages and rests upon the lower end S10 of the ramped surface. As the stairway is lowered and unfolded the lug travels up the (Ni ramped surface. The movement of the lug up the ramped surface causes the strut, to which the lug is attached, to be raised from a lowered position, in which it makes a small angle with the moveable support member to a raised position, in which it makes a large angle with the moveable support member. This in turn causes the entire handrail assembly to be raised from its collapsed position to its raised position.

In a particularly preferred embodiment, the stairway includes both positioning means and a collapsible handrail assembly, the respective functions of which are interrelated.

In this embodiment, the actuating means of the handrail raising assembly also functions as the projection of the positioning means. For ease of discussion, both will be hereinafter collectively referred to as the projection. Further, the second positioning member is provided adjacent the upper end of the ramped surface.

Accordingly, during unfolding of the stairway, the projection travels up the ramped surface, thereby effecting the elevation of the handrail assembly. The projection then enters the second positioning member.

When the projection is received in the second positioning member, the handrail assembly is stabilised, thereby minimising any undesired relative movement therebetween. This feature is a useful indication of whether the stairway is orientated within the desired angle range, and can therefore indicate whether the stairway is stable and safe to use. On the other hand, if a user notices that the handrail assembly is unstable, eg. it "wobbles", then he knows that the stairway is not orientated at a safe angle to the horizontal, and can readjust the stairway to a safe angle.

DESCRIPTION OF DRAWINGS C A collapsible stairway according to the invention may take any one of a variety of Sforms. It will be convenient to hereinafter describe the invention in greater detail by reference to particular embodiments thereof as shown in the accompanying drawings.

The particularity of these drawings is not to be understood as superseding the generality of the preceding description.

00 Further, it should be understood that the words "comprise", "comprises", S"comprising", "comprised" or the like, when used in this specification, are to be given r a non-exhaustive meaning and therefore are not intended to exclude other additives, components, integers or steps.

In the drawings: Figure 1 is a perspective view of a first embodiment of a collapsible stairway of the invention, in its in use condition.

Figures 2a and 2b are side and front views, respectively, of the first embodiment of the invention in its in use condition, as mounted under a truck tray.

Figure 3 is a side view of the first embodiment of the invention in its stored condition under a truck tray.

Figure 4 is a perspective view of a second embodiment of a collapsible stairway of the invention, in its in use condition.

Figures 5a and 5b are side and front views, respectively, of the second embodiment in its in use condition mounted under a truck tray.

Figures 6a and 6b are side and top views, respectively, of the second embodiment in its stored condition.

Figures 7a, 7b and 7c illustrate the operation of the handrail raising means and positioning means of the second embodiment.

Figure 8a is a perspective view of a third embodiment of a collapsible stairway of the invention, in its in use condition.

SFigure 8b is a detailed perspective view of the rotational retracting mechanism of the third embodiment.

(-i SFigure 9a and 9b are side and front views, respectively, of the third embodiment in its in use condition, as mounted under a truck tray.

Figure 10 Oa and 10 Ob are side and top views, respectively, of the third embodiment in Sits stored condition.

00oO Figure 11 is a perspective view of a fourth embodiment of a collapsible stairway of the invention, in its in use condition.

Figure 12 is a detailed view from below of the fourth embodiment, illustrating the attachment and hinging of a platform member.

Figure 12a is a detailed perspective view of Figure 12.

Figures 13 and 13a are perspective views from above and below, respectively, of the fourth embodiment in its stored condition.

Figures 14, 14a and 14b are side views of the fourth embodiment in various stages of movement from its stored to in use condition, respectively, illustrating the fact that the platform members remain parallel to the ground during the entire folding operation.

The stairway in accordance with the first embodiment shown in Figures 1 to 3 is described immediately below.

The collapsible stairway, indicated generally at 10, includes four platform members, comprising treads 12a, 12b, 12c and 12d, and support means 14. The stairway 10 is collapsible from its in use condition, illustrated in Figures 1, 2a and 2b, to its stored condition shown in Figure 3. The stairway 10 is mounted under a truck tray 16 (see Figures 2a, 2b and 3).

The support means 14 includes two elongate moveable support members comprising stringers 18 and 20. The treads 12a, 12b, 12c and 12d are laterally mounted by pins 22 for pivotable movement between the stringers 18 and

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SEach stringer 18 and 20 is pivotably mounted by a pivot 24 to a respective guiding support member, comprising slidable arms 26, 28. The stringers 18, 20 are pivotable about the pivots 24 from a first raised position (corresponding with the storage Scondition illustrated in Figure 3) to the second, lowered condition (corresponding with C 5 the in use condition illustrated in Figures 1, 2a and 2b).

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The support means 14 further includes two fixed support means comprising tracks 00 and 32. The tracks 30 and 32 are mounted under the truck tray 16. Each track 30, 32 includes a channel 34, 36, respectively, which is sized and positioned to slid ably NI receive thereon the slidable arms 26, 28. Moreover, with the stringers 18 and rotated into alignment with the slidable arms 26, 28 as in the stored condition of the IC stairway 10 (see Figure the stringers are also able to be received within the tracks 32. Thus, with the stairway in its stored condition, it is able to be retracted wholly under the truck tray 16.

As previously stated, each tread 12a, 12b, 12c, 12d is laterally pivotably connected, by pins 22, to the stringers 18, 20. The stairway 10 further includes orientating means 38 which cooperates with the pins 22 during unfolding of the stairway 10 to maintain the treads 12a, b, c, d in a substantially horizontal orientation, as the stairway is being unfolded. The orientating means 38 includes attachment means, in the form of hinges 40b, 40c and 40d, each of which is connected to a respective tread 12a, 12b, 12c, 12d and to a connecting means comprising a connecting bar 42. The connecting bar 42 is mounted for rotatable movement on a shaft 44, which is in turn mounted between the slidable arms 26, 28.

With the stairway 10 in its stored condition (see Figure 3) the hinges 40a, b, c, d are closed, enabling the treads 12a, b, c, d to be substantially aligned with the stringers 18, 20 and the connecting bar 42 and the treads 12a, b, c, d to be in substantially the same horizontal plane. As the stairway 10 is lowered into its in use condition, the stringers 18, 20 pivot downwardly. The connecting bar 42 tracks the movement of the stringers 18, 20 by virtue of its inter connection thereto via the treads 12a, b, c, d.

During this movement, the connecting bar 42 remains essentially parallel with the stringers 18, 20, and the treads 12a, b, c, d become vertically spaced from each other.

t During the downward, rotational movement of the stringers 18, 20, the pins 22 of each tread 12a, b, c, d remains in substantial horizontal alignment with the (-i N corresponding hinge 40a, b, c, d attached to that tread 12a, b, c, d. This substantial Shorizontal alignment of the pins 22 and the hinges 40a, b, c, d ensures that each tread 5 12a, b, c, d maintains a substantially horizontal orientation throughout the unfolding of the stairway 10 into its in use condition.

00 A second embodiment of the collapsible stairway will now be discussed, with reference to Figures 4, 5a, 5b, 6a, 6b, 7a, 7b and 7c. Like reference numerals refer to Ni like parts and to avoid repetition, discussion will concentrate on the features which 0 10 differ to those of the first embodiment.

The collapsible stairway 110 differs from the collapsible stairway 10 illustrated in Figures 1, 2a, 2b and 3 in a number of ways.

Firstly, the stairway 110 includes a handrail assembly 150. The handrail assembly 150 includes first and second struts 152, 154, supporting a handrail bar 156. The first and second struts 152,154 are each rotatably mounted at one end thereof to the stringer 118 at 152a, 154a, respectively, and rotatably mounted at 152b, 154b to handrail bar 156 at the other end thereof. The handrail assembly 150 also is collapsible from a raised position, as shown in Figures 4, 5a and 5b to a collapsed condition, as shown in Figures 6a and 6b.

The handrail assembly 150 includes a handrail raising means 158, including a ramped surface, comprising cam surface 164, provided on the upper surface 161 of an extending arm 160, and a projection, comprising lug 166, extending laterally from the first strut 152. The arm 160 is a forward extension of slidable arm 126. The lug 166 is engageable with the cam surface 164.

The stairway 110 also includes positioning means 168, comprising as a first positioning member the lug 162 and as a second positioning member, a slot 170. The slot 170 extends downwardly from the upper surface 161 of the arm 160 and is inclined towards the front of the stairway 110. The slot 170 is sized to snugly fit the lug 162 therein.

r The operation of the handrail raising means 158 and the positioning means 168 will now be described with reference to Figures 7a, 7b and 7c.

(-i SWith reference firstly to Figure 7a, the handrail raising means 158 and the positioning means 168 are shown with the stairway in its stored condition. The lug 162 rests on (N 5 the lower end of the cam surface 164. The first strut 152 makes a small angle with slidable arm 126 and stringer 118, the latter two being in substantial horizontal o00 alignment.

SAs the stairway is lowered from its stored condition, the lug 162 commences to travel (-i tr up the cam surface 164. T his action causes the fist strut 152 to pivot about pin 152a and to thereby be elevated and to increase the angle that the first strut 152 makes with the stringer 118. This in turn causes the rest of the handrail assembly 150 to be raised into its raised position.

Figure 7b shows the handrail assembly 150 in its raised position, at which stage, the lug 162 has just entered the slot 170 at the upper, open end 171 thereof. In this orientation the stringer 118 makes a first angle a' with the horizontal, which angle in this case is 35' By virtue of the receipt of lug 162 in the slot 170, the strut 152 is stabilised and undesired vertical or horizontal movement of the handrail assembly is minimised.

Referring now to Figure 7c, with further lowering of the stringer 118, the lug 162 moves further into the slot 170, until it reaches the lower, closed end 173 thereof, at which point any further downward movement of the lug 162 in the slot 170 is prevented. This movement of the lug 162 from the upper end 171 to the lower end 173 results in a slight overall lowering of the handrail assembly. With the lug 162 at the lower end 173 of the slot 170, the stringer 118 makes a second angle 3 with the horizontal, which angle in this case is 44'.

It is to be noted that the range of angles to horizontal assumed by the stringer 118, namely from 35' to 440, are within the limits stipulated by International Safety Standards for safe usage of stairways.

SThe stairway 110 is further distinguished from the stairway 10 by including means for assisting the lowering and raising of the stairway 110, in the form of a pneumatic piston 174.

The stairway 110 further includes means facilitating the movement of the slidable N 5 arms 126,128 within the tracks 130, 132, comprising roller 176. In order to simplify the construction of the stairway 110, at least two of the rollers 176 have been mounted

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00oO at respective ends of the shaft 144.

SA third embodiment of the collapsible stairway will now be discussed with reference t to Figures 8a, 8b, 9a, 9b, 10 Oa and 10 Ob. Again, like reference numerals refer to like parts and to avoid repetition, discussion will concentrate on those features which differ from those of the first and second embodiments.

The collapsible stairway 210 differs from the collapsible stairways 10 and 110 in that the former utilises a rotatable retraction mechanism, indicated generally at 278, instead of a sliding retraction mechanism as in the first and second embodiments.

Also, the collapsible stairway 210 is situated such that in its in use condition, the stairway 210 extends from the side of a semi-trailer truck tray, instead of from the side of from the rear of a truck tray; as in the first two embodiments. This is particularly evident in Figure 9a, in which the wheels of the semitrailer truck are indicated by reference numeral 279.

The rotational retraction mechanism 278 includes a fixed support member comprising a mounting plate 280 which is mountable to the underside of the truck tray 216. The stairway 210 is rotatably mounted on the mounting plate 280 about a rotational axis defined by a pin 282. The pin 282 is rigidly fixed on to the mounting plate 280. The stairway 210 is rotatably mounted to the mounting plate 280 via a rotatable mounting means comprising a laterally extending bar 284 extending across the top of the stairway 210, as part of an upper supporting structure 286. As is evident from the Figures 8a to 10b, the upper supporting structure 286 includes lateral supporting arms 288a and 288b to which the stringers 218, 220 are pivotably attached.

The stairway 210 also includes a mounting support, comprising a circular plate 290, which functions to support the laterally extending bar 284 during its rotation. The centre of the circular plate 290 coincides with the axis of rotation of the laterally t extending bar 284, and therefore with the pin 282. The pin 282 is rigidly fixed at the lower end thereof to the centre of the circular plate 290 and rigidly fixed at the upper end thereof to the mounting plate 280. Accordingly, the mounting plate 280, pin 282 F. and circular plate 290 comprise a rigid unit. The laterally extending bar 284 includes N 5 a centrally located aperture 292 through which the pin 282 extends. The laterally

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extending bar 284, and the depending stairway 210, are rotatable about the pin 282.

00oO Accordingly, in order to retract the stairway 210 from its in use condition into its stored condition, the stringers 218, 220 are rotated about the pivots 224 upwards in (i order to collapse the stairway 210. The collapsed stairway 210 is then rotated about the pin 282 approximately 900, so that the stairway is completely received under the NI truck tray 216. In this stored condition, the stringers 218, 220 extend in a direction substantially parallel with the length of the truck tray 216.

A fourth embodiment of the collapsible stairway will now be discussed with reference to Figures 11, 12, 12a, 13, 13a and 14.

The collapsible stairway 300 differs from the other embodiments in that the connecting bar 301 is repositioned, the tread hinge axles 308a are repositioned into the connecting bar 301 (to lower the overall profile of the stairway in its stored condition) and the pneumatic piston 174 is replaced by a coil spring 312.

Referring to Fig 11, it can be seen that the connecting bar 301 is attached to the connecting bar axle 302 by a connecting bar yoke 313. The connecting bar axle 302 is bolted to the guiding member303. The stair tread 306 is attached to the connecting bar 301 by a tread hinge 308 and tread hinge axle 308a. The tread hinge axle 308a is pivoted through the connecting bar 301.

A stair tread axle 307 is fixed to the underside of the stair tread 306 and fits into a stair tread axle housing 314 attached to the inner sides of the righthand stringer 304 and lefthand stringer 305 to allow the tread to pivot.

The lefthand stringer 305 is attached to the guiding member 303 by a left stringer pivot pin 309. The righthand stringer 304 is attached to the guiding member 303 by the right stringer pivot pin 310.

t A lift bar 311 holds the righthand stringer 304 and lefthand stringer 305 solidly in place allowing the stair treads to move freely.

SReferring to Figures 12 and 12a, the Stair tread 306 assembly is shown in detail. Each stair tread 306 has a separate stair tread axle 307 on each side to allow the connecting N 5 bar 301 to pass through the tread to create a smaller profile. The connecting bar 301 is positioned up and into the stair tread 306 assembly for this purpose.

00 00 When the collapsible stairway is withdrawn from its stowed position using the lift bar r"- 311, the weight of the structure causes it to pivot towards the ground. A dampening (Ni N spring 312 slows the decent making the unfolding a safe, smooth operation. The C 10 guiding member 303 remains stationary throughout the operation. The righthand stringer 304 and lefthand stringer 305 pivot down on a left stringer pivot pin 309 and right stringer pivot pin 310, respectively, which are attached to the guiding member.

The connecting bar 301 pivots on the connecting bar yoke 313, which is located on the connecting bar axle 302; thereby maintaining the stair treads 306 in the parallel position by the action of the stair tread hinge 308 and axle 308a which has its pivot point through the connecting bar 301.

As shown in Figures 14, 14a and 14b, the stair treads remain parallel to the ground and the stair tread axles 307 pivot in the stair tread axle housings 314 which are located at the inside of the left and right stringers. Stowing is the reverse of this procedure.

Ladders and stairways have always been a problem to negotiate, especially when not permanently secured. This invention has sought to overcome this problem by attaching a collapsible handrail mechanism to either or both sides of the stairway or ladder. The invention is particularly intended to be suitable for use with collapsible stairways or ladders.

The purpose of the handrail embodiment of the invention is to give sturdy support in all directions and height variations. It is suitable, for example, for marine gangways in which tides vary stair heights and is intended to be safe and sturdy at any height of tide.

The transport industry could also gain from the invention, as getting on and off machinery has been a safety concern.

V) Industry has similar problems where stairways need to be folded away to allow access, such 0 as for cranes and machinery.

STo assist with understanding the invention, reference will now be made to the accompanying N 5 drawings, which show one example of the invention, in which:

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Figure 101 shows the mechanical operation of the invention illustrating the stringer in the i stowed and down positions; 00 Figure 102 shows the invention attached to a set of collapsible stairs; Figures 102a and 102b show detailed views of the mechanism illustrated in Figure 102, t- 10 shown in the extended ("down") and stowed positions, respectively; and SFigures 103a and 103b show alternative views of the invention as illustrated in Figure 102.

Integers used in Figures: handrail latching mechanism, stair carriage, outer stringer, inner stringer, pivot pin, stanchion pin, stanchion, top plate, slide plate, inner plate, handrail, stair tread, right hand stringer, lift bar, (14).

Referring to Figure 101, it can be seen that the handrail mechanism is attached to the stair carriage with an outer stringer and inner stringer (3a) located to the carriage by a pivot pin The stanchion is located between the inner and outer stringer (3a) by the stanchion pin The stanchion slides through the latching mechanism on the slide plate preventing down movement. A top plate prevents upwards movement and the inner plate prevents any side movement.

In the operation of the handrail mechanism from the stowed position, when the stringer (3) and (3a) are lowered by the stairs or gangway the stanchion is forced to slide on the slide plate causing the stanchion attached to the stingers by stanchion pin to pivot up into the operational position.

Figure 102 shows the handrail mechanism attached to a set of collapsible stairs to illustrate the mechanism in relation to the stairs. The parts being the latching mechanism stringers and stanchions and handrail step n carriage assembly treads right hand stringer lift bar for collapsible 0 Ostairs (14).

Figure 102a illustrates the mechanism in the down position and Figure 102b shows the mechanism in the stowed position. Figure 103a is a two-dimensional front view of the N 5 handrail mechanism attached to collapsible stairs and Figure 103b is a side view with the

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stairs shown in the down position.

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00 SThe invention also relates to a restraining cradle and rest for rotating collapsible stairs.

The restraining cradle was devised to give a simple effective way to restrain the stairs and for neatly stowing them under the side of the tray or platform of trucks and other transport vehicles. Another aim of the design of the restraining cradle is to help to prevent the dislodging of any part during the vehicle's mode of travel.

The principle of the restraining cradle compared to other restraining devices of this nature is that it has few moving parts. This design has no springs or complicated catches to become fouled with mud and road grime thus precipitating failure. When the secondary retaining flap is turned to the open position the operating lever of the restraining cradle is revealed. Also revealed are the cradled stairs. By pulling the operating lever out the retaining dog is lowered by way of a transfer axle across the cradle body to allowing the stairs to be released. When the lever is released the counterweight returns the retaining dog to the restrained position. To return the stairs to the restrained position all that the operator has to do is to slide the stairs into the cradle. As the stairs slide in, the inside stringer of the stairs strikes the retaining dog forcing it to overcome the weight of the counterweight and thus restraining the stairs in the packed away position. The operator would then just flip the secondary retaining flap to the closed position preventing the operating lever from moving. The advantage of the restraining cradle is that it is simple and fast to operate eliminating complicated time wasting procedures.

To assist with understanding the invention, reference will now be made to the accompanying drawings, which show one example of the invention, in which: Figures 201 a b show the restraining cradle in the stowed position; Figures 201 c d show the mechanical operation of the cradle; Figure 201 d shows the restraining cradle in the operational position; and Figures 202 a b show the restraining cradle parts from the front and rear (b) positions.

(-i Integers used in Figures: restraining dog, cradle body, operating lever, N 5 lever support bracket, counter weight, counter weight stopper block,

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secondary retaining flap, transfer axle, position bracket, secondary Sretaining flap stopper block, slide ramp, secondary retaining flap pivot pin, 00 (12).

kn 10 Figure 201 a shows the cradle body in a closed position. It can be seen that the restraining dog is preventing the stairs from moving. The secondary restraining (-i flap is in the closed position sitting on the slide ramp In Figure 201 b, the operating lever and counter weight are in the closed position and secondary restraining flap is closed to prevent any movement of the operating lever Figure 201d shows the cradle body in an open position. It can be seen that the restraining dog is in the down position with the secondary restraining flap in the open position. This then allows the operating lever to be extended out to operate the counter weight thus lowering the restraining dog Referring to Figure 202, Figure 202 a details the forward cradle position for the stairs on the cradle body The restraining dog is shown and is welded to the transfer axle A position bracket is also welded to the cradle body positions the stairs in a neat fit for transit. The secondary restraining flap is attached to the cradle body by means of a pivot pin which is a normal nut and bolt with the nut welded securely to the bolt. The secondary restraining flap has a secondary restraining stopper When placed in the open position the stopper (10) prevents further travel. The secondary restraining flap sits on the slide ramp (11) when in the closed position.

Figure 202 b details the rear of cradle body which shows the counterweight welded to the transfer axle The operating lever passes through the lever support bracket and is attached through a drilled hole into the counter weight the end of the operating lever having a washer welded to it, preventing separation.

t A counter weight stopper block welded to the cradle body prevents over travel of the counterweight (-i SFigure 201 c shows the mechanical operation of the invention. Operation of the I 5 restraining cradle begins with the secondary restraining flap being turned on the

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pivot pin (12) with the secondary restraining stopper (10) coming to rest on the rear t surface of the cradle body The secondary restraining flap is now in the open 00 0 position. This open position reveals the operating lever when the lever is pulled out the lever slides through a lever Support turning the counterweight to lower tn 10 the retaining dog by way of the transfer axle The counterweight then returns to the closed position by means of the off-centre design of the counterweight.

The stairs are now ready to be moved out and into their operating position. When the stairs slide back into the cradle body the stair stringer strikes retaining dog The force overcoming the counterweight and moving the retaining dog (1) downward to allow the stairs into the position bracket thus placing the stairs in the neatly stowed position. All that is required to complete the operation is to return the secondary restraining flap to the closed position by turning the flap on the pivot pin (12) until it rests on the sliding ramp The stairs are now neatly stowed.

The restraining cradle is welded into the sub structure of the vehicle tray or body.

Preferably the stairway and cradle are positioned under the tray so as not to take up valuable cargo space.

The folding, rotation and stowage of the collapsible stairs are illustrated in detail in Figures 301, 302 and 303.

It is to be understood that various alterations, modifications, and/or additions may be introduced into the composition and/or arrangement of steps previously described without departing from the spirit or ambit of the invention.

Claims (19)

1. 3. The stairway of claim 1 or 2, wherein said support means includes at least one elongate, moveable support member having said at least one platform member pivotably attached thereto at respective spaced intervals along its length.
2. 4. The stairway of claim 3, wherein said elongate, moveable support member is mounted for pivotable movement relative to said elevated surface, said elongate support member being pivotable from a first raised position to a second lowered position. The stairway of claim 3 or 4, wherein said support means includes two said elongate, moveable support members, each said moveable support member being disposed at a respective lateral side of each platform member.
3. 6. The stairway of any preceding claim, wherein said stairway is retractable to a position at least partially under the elevated surface when in its storage condition.
4. 7. The stairway of claim 6, wherein said support means further includes at least one fixed support member mountable under said elevated surface, each moveable support member being cooperable with said at least one fixed support member in order to retract said stairway into its storage condition.
5. 8. The stairway of claim 6 or 7, wherein each moveable support member is slidably received in said corresponding fixed support member. S9. The stairway of claim 7 or 8, wherein each moveable support member is provided with a guiding support member to assist in guiding the moveable support member in the fixed support member. The stairway of claim 9, further including stop means to limit the extent of travel of said guiding and moveable support members in the fixed support members. V 11. The stairway of any preceding claim, further including orientating means which 00oO cooperates with the moveable support members to ensure substantially horizontal Sorientation of each platform member. (-i S12. The stairway of claim 11, wherein the orientating means includes respective attachment means attached to each platform member and the attachment means of each platform member are interconnected by a connecting means.
6. 13. The stairway of claim 12, wherein the connecting means is mounted for pivotable movement to track the pivotable movement of each moveable support members.
7. 14. The stairway of claim 13, wherein the connecting means is hingedly connected to a shaft mounted on one or both guiding support members. The stairway of claim 6 or claim 7, wherein said fixed support member comprises a mounting plate on which said stairway is rotatable in order to be retracted into said storage condition.
8. 16. The stairway of claim 15, wherein said storage condition is achieved by pivoting said elongate support members into said raised position, thereby collapsing said stairway, and rotating said collapsed stairway approximately 900 to a position underneath said elevated surface.
9. 17. The stairway of any preceding claim, further including handle means to assist in gripping the stairway as it is moved between the stored and in use conditions.
10. 18. The stairway of any preceding claim, further including positioning means for positioning the or each elongate support member at a predetermined angle to horizontal between a' to 3. V) 19. The stairway of claim 18, wherein the angle range a° to 3o complies with the 0 International Safety Standard.
11. 20. The stairway of claim 19, wherein the angle range is between 26.50 and 45' 4
12. 21. The stairway of claim 18, wherein each elongate support member makes an angle of between 35' and 440 to horizontal. oO 22. The stairway of any one of claims 18 to 21, wherein said positioning means Scomprises first and second positioning members, said first member including a projection receivable within said second member including a recess or a slot. N 23. The stairway of claim 22, wherein said second member is orientated such that with the projection received therein at a first end of said recess or slot, the moveable support member makes the angle a' to the horizontal, and with the projection received therein at a second end of said recess or slot, the moveable support member makes the angle 3 to the horizontal.
13. 24. The stairway of any one of claims 22 or 23, wherein the first positioning member comprises an elongate element, extending from a moveable support member, from which said projection extends laterally and said second positioning member comprises a downwardly extending inclined slot which is sized so as to snugly receive said projection. The stairway of any preceding claim, further including a collapsible hand supporting means.
14. 26. The stairway of claim 25, wherein said hand supporting means comprises a handrail assembly including at least one strut supporting a handrail bar.
15. 27. The stairway of claim 26, further including handrail raising means operable to raise said handrail assembly from a collapsed position to a raised position, said handrail raising means including a ramped surface engageable by an actuating means.
16. 28. The stairway of claim 27, wherein said actuating means comprises a lug extending from one of said at least one strut, wherein during unfolding of said stairway from in its stored condition, said lug travels up said ramped surface, thereby causing said one strut to be raised together with said handrail assembly into said raised position.
17. 29. The stairway of claim 27 or 28, wherein said stairway includes both said 5 positioning means and said handrail raising means, said actuating means being said projection and said positioning means being provided adjacent the upper end 00oO of said ramped surface.
18. 30. A collapsible handrail mechanism for steps or a ladder including: (-i an outer stringer and an inner stringer jointly pivotable about a pivot point; (-i a stanchion located between the outer and inner stringers and pivotally mounted to at least one of the stringers; a latching mechanism through which the stanchion passes and to which at least one of the stringers is pivotally mounted at the said pivot point; the latching mechanism having a slide plate preventing substantial downwards movement of the stanchion, a top plate preventing substantial upwards movement of the stanchion, and a side plate preventing substantial sideways movement of the stanchion; whereas, in operation of the handrail mechanism from a stowed position, when the stringers are lowered the stanchion is thereby forced to slide on the slide plate causing the stanchion to pivot about its mounting up into an operational position
19. 32. A collapsible stairway, substantially as herein described with reference to any one of the embodiments shown in the accompanying drawings. Donald John EMMERTON Dated this 22 nd day of February 2005 by his Patent Attorneys PIPERS MILLS OAKLEY