Access structure

Abstract

An access structure 1 for an automotive vehicle, comprising a ladder 2 having a crosspiece 7 and being movable between a stowed configuration and a deployed configuration. There is also a stowage rack

Description

Technical Field The present disclosure relates to an access structure for an automotive vehicle. In particular, but without limitation, the present disclosure relates to an access structure to allow a person to enter and / or exit a vehicle via an elevated entry / exit point. Background Automotive vehicles can be provided with access structures such as ladders to provide a person, such as a driver or passenger, with access to the vehicle. Such access structures may be particularly useful for large vehicles, for example heavy goods vehicles, trucks, vans, motorhomes, camper vans and so forth. Large vehicles often have doors elevated a considerable distance above the ground, which may be difficult for a person to access. While access structures such as ladders have hitherto been provided that are attachable to a vehicle to facilitate access to the vehicle, such ladders need to be sufficiently strong to withstand the weight of a person during use. As such, conventional ladders are manufactured from a relatively heavy material which can add significantly to the overall weight of the vehicle, thereby increasing fuel consumption. There is therefore a need for an access structure that is both strong and lightweight. Summary A first aspect of the disclosure provides an access structure for an automotive vehicle, the access structure comprising: a ladder having a crosspiece, the ladder configured to be movable between a stowed configuration and a deployed configuration; a stowage rack configured to receive the ladder when the ladder is in the stowed configuration; and a support bracket configured to support the crosspiece of the ladder when the ladder is in the deployed configuration. The crosspiece may optionally be a topmost rung of one or more rungs of the ladder when the ladder is in the deployed configuration. The support bracket optionally comprises first and second guide members configured to receive respective side rails of the ladder when the ladder is in the deployed configuration. Optionally, the first and second guide members each subtend an acute angle downwardly with respect to a plane extending outwardly from an underside of the automotive vehicle when the access structure is attached to the automotive vehicle. The access structure optionally further comprises a locking mechanism movable between a locked position and an unlocked position, the locking mechanism being configured to retain the ladder in the stowed configuration when the locking mechanism is in the locked position. The locking mechanism optionally comprises an indicator configured to indicate whether the locking mechanism is in the locked position or the unlocked position. Alternatively or in addition, the locking mechanism optionally comprises a biasing mechanism configured to bias the locking mechanism to the locked position. A second aspect of the disclosure provides an access structure for an automotive vehicle, the access structure comprising: a ladder movable between a stowed configuration and a deployed configuration; a stowage rack configured to receive the ladder when the ladder is in the stowed configuration; a locking mechanism movable between a locked position and an unlocked position, the locking mechanism being configured to retain the ladder in the stowed configuration when the locking mechanism is in the locked position; and an indicator configured to indicate whether the locking mechanism is in the locked position or the unlocked position. The locking mechanism optionally comprises a biasing mechanism configured to bias the locking mechanism to the locked position. The access structure optionally further comprises a support bracket configured to support the crosspiece of the ladder when the ladder is in the deployed position. The access structure is optionally formed from aluminium, an alloy of aluminium or other aluminium-based material. In particular, any or all of the ladder, stowage rack and / or support bracket may be formed from formed from aluminium, an alloy of aluminium or other aluminium-based material. The stowage rack optionally comprises an attachment arrangement configured to attach the access structure to the automotive vehicle. Brief Description of the Drawings So that the invention can be fully understood, the following drawings are included in which: Figure 1 is a perspective view of an access structure according to an embodiment of the invention in a deployed configuration; Figure 2 is a perspective view of the access structure of Figure 1 in a stowed configuration; Figure 3 is a perspective view of a support bracket of the access structure shown in Figures 1 and 2; Figure 4 is a close-up perspective view of the access structure shown in Figures 1 and 2 in a stowed configuration illustrating a locking mechanism; Figure 5 is a close-up perspective view of the access structure shown in Figures 1 and 2 in a deployed configuration illustrating the locking mechanism; and Figure 6 is a cross-sectional view of a side rail of a stowage rack of the access structure shown in Figures 1 and 2. Detailed Description Embodiments of the present invention provide an access structure for an automotive vehicle to allow a person to enter or alight from the vehicle. The access structure may be configured to be attached to a vehicle such as a heavy goods vehicle, truck, van, motorhome, camper van, trailer or other suitable vehicle. In use, the access structure is typically attached to an underside of such a vehicle, although the access structure could alternatively be attached elsewhere on a vehicle (e.g., to a roof or a flatbed). Figure 1 shows an access structure 1 in a deployed configuration. Figure 2 shows the same access structure 1 in a stowed configuration. The access structure 1 comprises a ladder 2, a stowage rack 3 and a support bracket 4. The ladder 2 is configured to be movable between the deployed configuration shown in Figure 1 and the stowed configuration shown in Figure 2. The stowage rack 3 is configured to hold the ladder 2 when stowed therein, as shown in Figure 2, and to allow the ladder to slide outwardly from the position shown in Figure 2 to adopt the deployed configuration shown in Figure 1. The end of the ladder 2 that is at the top of the ladder 2 when the ladder 2 is in the deployed configuration may be termed the proximal end of the ladder 2. The end of the ladder 2 is at the bottom of the ladder 2 when the ladder 2 is in the deployed configuration may be termed the distal end of the ladder 2. Depending on the height of the vehicle to which the access structure 1 is attached, when the ladder 2 is deployed the distal end thereof may hang freely and not contact the ground. As described in more detail below, the access structure 1 may be manufactured from a lightweight material such as aluminium, in contrast to conventional vehicle access structures which are typically made from heavier materials such as steel. The inventors have recognised that the strength required to support a human operator using the access structure 1 to enter and exit a vehicle may be imparted by providing a support bracket 4 to support the proximal end of the ladder 2 when the ladder 2 is deployed rather than manufacturing the access structure from a heavier material such as steel. The ladder 2 comprises first and second side rails 5a, 5b extending parallel to a main axis of the ladder 2. The ladder 2 comprises one or more rungs 6. In the example shown, the ladder 2 comprises three rungs 6a, 6b, 6c. However, the ladder 2 may comprise more or fewer rungs, depending on the height above ground of a vehicle (or a portion of the vehicle) to which the ladder 2 is intended to be attached. Each of the rungs 6a, 6b, 6c is perpendicular to, and extends between, the side rails 5a, 5b to provide a step for a person when using the access structure 1 to enter or to alight from a vehicle to which the access structure 1 is attached. The ladder 2 comprises a crosspiece 7 proximate to the proximal end of the ladder 2. The crosspiece 7 is perpendicular to, and extends between, the side rails 5a, 5b of the ladder 2. The crosspiece 7 may be longer than the distance between the side rails 5a, 5b, such that a portion at either end of the crosspiece 7 extends beyond the side rails 5a, 5b of the ladder 2 to form a pair of lugs 26 (only one of which is visible in Figure 1). The crosspiece 7 is configured to be supported by the support bracket 4 when the ladder 2 is deployed. The support bracket 4 is configured to support the crosspiece 7 of the ladder 2 in the deployed configuration. The support bracket 4 allows the crosspiece 7 to rotate around an axis 18 of the crosspiece 7, thereby allowing the ladder 2 to move between the stowed and deployed configurations. In some embodiments, the crosspiece 7 may also form a topmost rung of the ladder when the ladder 2 is deployed. The stowage rack 3 comprises side rails 8a, 8b and a crossbar 9. The crossbar 9 extends between and connects the side rails 8a, 8b. The crossbar 9 provides strength to the structure of the stowage rack 3. The side rails 8a, 8b may have a series of holes provided therein, thereby reducing the weight of the stowage rack 3 and access structure 1. Figure 6 shows a cross-section of a side rail 8a of the stowage rack 3. The side rail 8a comprises a web 20, two inner flanges 21 a, 21 b and outer flange 22. The inner flanges 21a and 21b extend perpendicularly from the web 20 and towards the other side rail 8b. The outer flange 22 extends perpendicularly from the web 20 and away from the other side rail 8b. The web 20 and the inner flanges 21a, 21b collectively define an elongate track 23. The side rail 5a of the ladder 2 can slide within the track 23 when moving between the stowed and deployed configurations. The track 23 and the locking mechanism 12 (described below) constrain the ladder 2 when in the stowed configuration, and thereby substantially prevent movement of the ladder 2. The other side rail 8b is a mirror image of side rail 8a. The description of the side rail 8a applies mutatis mutandis to the other side rail 8b. The side rails 8a, 8b of the stowage rack 3 may each be manufactured from a single extruded piece of aluminium. It will be appreciated that the cross-section shown in Figure 6 can be formed by extrusion. Other cross-sectional profiles are possible. The stowage rack 3 may be provided with an attachment mechanism to attach the access structure 1 to a vehicle. For example, the side rails 8a, 8b may each be provided with a set of flanged bolt loops 10 along their length. The flanged bolt loops 10 are configured to receive a bolt extending therethrough to attach the stowage rack 3 of the access structure 1 to the vehicle. For example, the underside of a vehicle chassis may be provided with suitably positioned apertures to receive a bolt extending through the flanged bolt loops 10. The access structure 1 may thus be securely fastened to the underside of the vehicle. Alternatively or in addition, the flanged bolt loops 10 may be used to attach the stowage rack to some other suitable structure on the vehicle. Figure 3 illustrates the support bracket 4 with other components of the access structure 1 removed for clarity. The support bracket 4 comprises one or more shelf portions 24, one or more guide members 11a, 11b, and one or more stops 25a, 25b. In the example shown, the support bracket 4 comprises a single shelf portion 24, two guide members 11a, 11b, and two stops 25a, 25b. The shelf portion 24 is substantially planar. The length of the shelf portion 24 is slightly less than the distance between the side rails 5a, 5b of the ladder 2. When the access structure 1 is attached to a horizontal surface of a vehicle, the shelf portion 24 is substantially horizontal. The shelf portion 24 is configured to receive the crosspiece 7 of the ladder 2 when the ladder 2 is in the deployed position. A guide member 11a, 11 b is positioned on each side of the shelf portion 24. The guide members 11a, 11b are configured to receive respective side rails 5a, 5b of the ladder 2 when the ladder 2 is in the deployed configuration. The distance between the guide members 11a, 11b is substantially equal to the distance between the side rails 5a, 5b of the ladder 2. The guide members 11a, 11b each subtend an acute angle (for example, 70 degrees) downwardly with respect to the plane of the shelf portion 24. To put this another way, the guide members 11a, 11b each subtend an acute angle downwardly with respect to a plane extending outwardly from an automotive vehicle when the access structure 1 is attached to the automotive vehicle. As such, the support bracket 4 can support the ladder 2 in a position that is convenient for a person as they ascend to or descend from a vehicle to which the access structure 1 has been attached. More particularly, the guide members 11a, 11b can orient the ladder 2 at an angle that is convenient for a person as they ascend to or descend from the vehicle. The rails side rails 5a, 5b of the ladder 2 may slide over the guide members 11a, 11b when the ladder is moved between the deployed and stowed configurations. A stop 25a, 25b is positioned on an outermost side of each guide member 11 a, 11 b. In other words, a stop 25a, 25b, is positioned on the side of each guide member 11a, 11b that is furthest away from the shelf portion 24. The stops 25a, 25b are substantially perpendicular to the shelf portion 24. Thus, when the access structure 1 is attached to a horizontal surface of a vehicle, the stops 25a, 25b are substantially vertical. The stops 25a, 25b are configured to receive the crosspiece 7 of the ladder 2 when the ladder 2 is in the deployed position. More particularly, a lug 26 at either end of the crosspiece 7 bears against a respective stop 25a, 25b when the ladder 2 is in the deployed position. The support bracket 4 may be formed from a single sheet of metal. For example, the support bracket 4 may be formed by cutting and bending an aluminium plate. The support bracket 4 may thus be simple and inexpensive to manufacture. The support bracket 4 may be welded or fastened to the stowage rack 3. For example, the support bracket 4 may be welded or fastened to the side rails 8a, 8b of the stowage rack 3. the support bracket 4 provides load-bearing support to the ladder 2 and a person as they ascend to or descend from a vehicle using the ladder 2. In particular, the shelf portion 24 and the stops 25a, 25b are configured to provide load-bearing support to the crosspiece 7 when the ladder 2 is in the deployed position. The guide members 11a, 11b are configured to provide load-bearing support to a respective side rail 5a, 5b when the ladder 2 is in the deployed position. As mentioned above, the distal end of the ladder 2 may hang freely when the ladder 2 is in the deployed configuration, such that ladder 2 is not supported by the ground. The support bracket 4 may thus bear the combined weight of a person using the ladder 2 and the ladder 2 itself. In this manner, the support bracket 4 reinforces the stowage rack 3 when the ladder 2 is loaded. The support bracket 4 advantageously allows the access structure 1 to be manufactured from a lighter material than access structures of a type known in the art. For example, while conventional access structures may be manufactured from steel, the presence of the support bracket 4 allows the access structure 1 disclosed herein to be manufactured from aluminium. As such, the access structure 1 may be significantly lighter than conventional access structures. Providing an access structure lighter than conventional access structures is advantageous since it can result in reduced fuel consumption compared with vehicles to which conventional access structures are attached. When a vehicle to which an access structure 1 has been attached is being driven, various forces can act on the ladder 2 including forces that may urge the ladder 2 to slide out of the stowage rack 3. Referring To Figure 4, the access structure 1 may therefore be provided with a locking mechanism 12 configured to lock the ladder 2 in the stowed configuration while the vehicle is moving. The locking mechanism 12 comprises an arm 13 having a detent 14 at a distal end thereof. The detent 14 engages with the distal end of the ladder 2. In the example shown, the detent 14 engages with the distal end of a side rail 5b of the ladder 2. In more detail, when the side rail 5b of the ladder 2 has a hollow box section, as shown in Figure 4, the detent 14 may engage with a wall of the box section. In another example (not shown in the figures), the detent may engage with the bottom rung 6a of the ladder. Other arrangements of achieving engagement between the arm 13 and / or detent 14 and the ladder 2 are possible. The locking mechanism 12 is said to be in a locked position when it is engaged with the ladder 2 as shown in Figure 4, such that ladder 2 is prevented from moving from the stowed configuration to the deployed configuration. The locking mechanism 12 is said to be in an unlocked position when it is disengaged from the ladder 2 as shown in Figure 5, such that the ladder 2 can move between the stowed and deployed configurations. The arm 13 of the locking mechanism 12 may be biased towards the locked position using a spring mechanism 15 or other suitable biasing mechanism. The spring mechanism 15 thus helps to hold the ladder 2 in the stowed configuration. The arm 13 of the locking mechanism 12 may be provided with a handle 16 to allow an operator (e.g., a driver or passenger of a vehicle to which the access structure 1 is attached, or some other user of the access structure 1) to move the locking mechanism 12 between the locked position and the unlocked position. An upstanding surface of the support bracket 4 (e.g., the stop 25b) may have wording (such as “Locked” and “Unlocked”) or graphical elements marked thereon in positions proximate the handle 16 corresponding to the respective locked and unlocked positions of the handle 16 of the locking mechanism 12. The wording or graphical elements may be marked on the support bracket by printing, engraving, attachment of sticker(s) or any other suitable means. The handle 16 and the support bracket 4 thereby form an indicator 17 to indicate to an operator whether the locking mechanism is in the locked position or the unlocked position. Providing an indication of whether the locking mechanism is in the locked position is advantageous since it provides visual confirmation to an operator that the ladder 2 has been safely stowed within the stowage rack 3 of the access structure 1. In use, the ladder 2 may be stowed in the position shown in Figures 2 and 4, referred to herein as the stowed configuration. In this position, the arm 13 of the locking mechanism 12 is biased by the spring mechanism 15 into the locking position, and the distal end of the ladder 2 is held in place by the detent 14. The handle 16 of the locking mechanism 12 is proximate the wording “Locked” on the support bracket 4, such that the indicator 17 of the access structure 1 indicates that the ladder 2 is locked within the stowage rack 3. To deploy the ladder 2, the operator first moves the handle 16 of the locking mechanism 12 to the unlocked position, thereby moving the arm 13 of the locking mechanism 12 such that the detent 14 no longer holds the distal end of the ladder 2 in place. This results in the handle 16 of the locking mechanism 12 being proximate the wording “Unlocked” on the support bracket 4, such that the indicator 17 of the access structure 1 indicates that the ladder 2 is not safely stowed in the stowage rack 3. The ladder 2 may then be pulled by the operator to slide out of the stowage rack 3 so that the crosspiece 7 rests in the support bracket 4. The ladder 2 may then be rotated around the axis 18 of the crosspiece 7 with side rails 5a, 5b of the ladder 2 being supported by guide members 11a, 11b of the support bracket 4. The ladder 2 thus adopts the position shown in Figures 1 and 5, referred to herein as the deployed configuration. To stow the ladder 2, a reverse operation may be performed. The operator rotates the ladder 2 upwardly about the axis 18 of the crosspiece 7 so that the ladder 2 is substantially parallel with respect to the stowage rack 3. The operator then pushes the ladder 2 into the stowage rack 3. Once the distal end of the ladder 2 has passed the detent 14, the spring mechanism 15 of the locking mechanism 12 causes the arm 13 to move into the locked position. When the arm 13 moves to the locked position, the handle 16 of the locking mechanism 12 moves proximate to the word “Locked” on the support bracket 4. The indicator 17 thus provides visual confirmation to the operator that the ladder 2 is stowed within the stowage rack 3.

Claims

1. An access structure for an automotive vehicle, the access structure comprising: a ladder having a crosspiece, the ladder configured to be movable between a stowed configuration and a deployed configuration;a stowage rack configured to receive the ladder when the ladder is in the stowed configuration; anda support bracket configured to support the crosspiece of the ladder when the ladder is in the deployed configuration.

2. The access structure of claim 1, wherein the crosspiece is a topmost rung of one or more rungs of the ladder when the ladder is in the deployed configuration.

3. The access structure of claim 1 or claim 2, wherein the support bracket comprises first and second guide members configured to receive respective side rails of the ladder when the ladder is in the deployed configuration.

4. The access structure of claim 3, wherein the first and second guide members each subtend an acute angle downwardly with respect to a plane extending outwardly from an underside of the automotive vehicle when the access structure is attached to the automotive vehicle.

5. The access structure of any preceding claim, further comprising a locking mechanism movable between a locked position and an unlocked position, the locking mechanism being configured to retain the ladder in the stowed configuration when the locking mechanism is in the locked position, wherein the locking mechanism comprises an indicator configured to indicate whether the locking mechanism is in the locked position or the unlocked position.

6. The access structure of claim 5, wherein the locking mechanism comprises a biasing mechanism configured to bias the locking mechanism to the locked position.

7. An access structure for an automotive vehicle, the access structure comprising: a ladder movable between a stowed configuration and a deployed configuration;a stowage rack configured to receive the ladder when the ladder is in the stowed configuration;a locking mechanism movable between a locked position and an unlocked position, the locking mechanism being configured to retain the ladder in the stowed configuration when the locking mechanism is in the locked position; andan indicator configured to indicate whether the locking mechanism is in the locked position or the unlocked position.

8. The access structure of claim 7, wherein the locking mechanism comprises a biasing mechanism configured to bias the locking mechanism to the locked position.

9. The access structure of claim 6 or claim 7, further comprising a support bracket configured to support the crosspiece of the ladder when the ladder is in the deployed position.

10. The access structure of any preceding claim, formed from aluminium or an alloy of aluminium.

11. The access structure of any preceding claim, wherein the stowage rack comprises an attachment arrangement configured to attach the access structure to the automotive vehicle.

Images