AU672706B2 - Access ladder - Google Patents

Description

I_

Our Ref: 516965 P/00/011 Regulation 3:2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT

S

o S Applicant(s): Address for Service: Hedweld Engineering Pty Ltd Broke Road MOUNT THORLEY Via Singleton NSW 2330

AUSTRALIA

DAVIES COLLISON CAVE Patent Trade Mark Attorneys Level 10, 10 Barrack Street SYDNEY NSW 2000 Invention Title: Access ladder The following statement is a full description of this invention, including the best method of performing it known to me:- 5020 slL(~P ~Bsl~ II~ l- "111111111 1 ill I ACCESS DEVICE FIELD OF THE INVENTION The present invention relates to an access device, such as a ladder, which provides access between a substrate surface and an elevated surface. The present invention, in particular, relates to a movable or retractable access device, which is movable between a first position or storage position and a second position or operable position.

BACKGROUND AND RELATED ART A variety of different access device configurations for removably or retractably providing an access member between operable and storage positions are presently known.

The most well known of these include ladders wherein a portion of the ladder may be extended or slid relative to an adjacent portion of a ladder, or, whereby a ladder is pivoted i* about one end thereof, between a storage position and an operable position.

Such prior art access ladders have generally operated by air cylinder means or the like, however, the present invention is preferably implemented by utilising an actuator.

SUMMARY OF THE INVENTION The present invention seeks to provide an access device which may be used in alterative to the above device, and which overcomes certain disadvantages of prior art access devices.

"The present invention also seeks to provide an access device which is conveniently raised and lowered taking up minimal space in a storage position, and whi.oh is provided in an operable position at any convenient angle which complies with the local relevant standard or regulations.

In one broad form, the present invention provides an access device, to provide ,ctcess between a substrate surface and an elevated surface, comprising: a fixed support means, attached to or integral with said elevated surface; p:\wl)docs\anid\475250.lhed\nJc

P-

_I~

-2an access member movable between a first position wherein a first end of said access member is substantially vertically adjacent to said support means, and, a second position wherein a second end of said access member is substantially vertically adjacent to said support means; and, a pair of arms, each arm pivutally connected, at a first end thereof to said support means, and, at a second end thereof to said access member, in such a configuration that said access member may be moved between said first and second positions whilst maintaining said second end of said access member elevated relative to said first end of said access member.

Preferably, one or both of said arms is each provided with at least one dogleg bend therealong.

Also preferably, said access device further comprises an arm support rail on at least one side of said ladder.

Most preferably, in said second position, said access member is inclined at approximately 620 relative to a substantially horizontal substrate surface.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become more fully understood from the following detailed description of a preferred but non-limiting embodiment thereof, described in connection with 20 the accompanying drawings, wherein: Fig. 1 shows the access device in accordance with the present invention in an l e p:\wpd=ocu\amJ475250.hed\ajc ~araP--~ 3operable or second position; Fig. 2 shows the access ladder is a storage or first position; Fig. 3 illustrates thie tangential arcs in which the pivotal connections between thle arms and thle access ladder undergo during movement bctween said first and second positions; Fig. 4 illustrates an alternative prefcrred embodiment of thle access devicc, embodied as a ladder, Fig, 4 showing the First position thereof; Fig. 5 illustrates this alternative embodiment of the ladder in a second position thereof', F-ig. 6 illustrates yet a further preferred embodiment of thle access device embodied as a ladder in a first position thereof, Fig. 7 illustrates the second preferred embodiment of the invention in a second position thereof;, and, Fig. 8 illustrates another preferred embodiment of the invention showing the 1 5 various positions thereof.

DIETAI LED DESCRIPTION OP, PREFERRED EMBODIMENTS Throughout the drawings, like numerals will be used to identify similar features, except where expressly otherwise indicated.

The access device, as illustrated in the drawings, and generally designated by the numeral 1, provides access between a substrate surface 2 and an elevated surface 3. The access device 1, comprises fixed support means 4, whiich is either attached to or integral with said elevated surface 3. It also comprises an access member 5 which is movable betweeni the first position shown in [Fig. 2, and, the second position shown in Fig. 1 It will he immediately apparent that there is a similarity between the position of the access device illustrated in Figs. 1, 5 and 7. It will likewise be seen there is a similarity between the positions of the access device shown in Figs. 2, 4 and 6. That is, Figs. I, and 7 all illustrate various embodiments of the access device in the 'downiward' or 'operable' position, or, the "second" position. Similarly, Figs. 2, 4 and 6 illustrate various embodiments of the access device in the 'upward', 'storage' or 'retractable' position, or the "First" position.

As will be seen in Fig. 1, in the downward or operable position, a first end 6 of pA\wpdOCS~ai~id\47525O. Iicd\ajc -4the access device 5 is provided near to a substrate surface 2, and a second end 7 of the access device 5 is provided substantially adjacent to an elevated surface 3. In a preferred embodiment, wherein the access device 5 is embodied as a ladder witli a plurality of steps therealong between the first and second ends 6 and 7 respectively, a person may easily obtain access between the substrate surface and the elevated surface 3. Then, after access is obtained, the access device is adapted to be removed or retracted to the first position shown in Fig. 1. Movement may be facilitated either manually, hydraulically, electrically, mechanically, pneumatically or any combination of the aforesaid. Movement is controlled by the provision of a pair of arms 8 and 9, each arm having a first end 10, 11 thereof, respectively, pivotally attached to the support means 4, and a second end 12 and 13 pivotally attached to the access member 5. In use, the access member will be understood to be transferred from the first position 14 to the second position 15, as shown in Fig. 3 via the tangential movement of the second ends of the arms 8 and 9.

Most preferably, when the access device is embodied as a stairway or a ladder, when the ladder is in the operable or downward position, it is adapted to be inclined to the horizontal at an angle of between 600 and 75°, and perhaps most preferably, at an angle of 62-. This allows for easy climbing of the steps provided along the length of the ladder. Other angles of inclination may of course be utilised if a 'rung' ladder rather than "a 'step' ladder is embodied, of if the access device is used for other uses other than for ladders.

Tie embodiment shown in Figs. 4 and 5 and that of Fig. 8, are each not "substantially different to the embodiments shown in Figs. 1 to 3, with the exception that the arms 8 and 9 are embodied as straight 'arms', rather than being of dogleg shape.

Differently shaped arms will be understood to be embodied to provide for different angles of inclination of the ladder in the operable and storage positions. For ease of understanding and by way of further example, an alternative embodiment is shown in Figs. 6 and 7, wherein only one of the arms is provided with a dogleg shape. It will be immediately apparent that there is a different storage or first position enabled by the provision of a single upper dogleg arm. In this respect, attention is drawn to the differences in storage positions of the ladder shown in Figs. 4 and 6. It will be appreciated that the double doglegs provided in the embodiment of Fig. 8 enable the ladder to be provided in a storage position wherein the first end 6 of the ladder 5 is provided totally above the elevated surface 3 i.e. fully retracted.

1):\wpldocs\amnd\475250.11ed\ajc

I

It will be appreciated that there are a wide variety of applications for such a ladder. It will be apparent that the ladder is adapted to provide access to any type of vehicle, particularly, earth moving equipment wherein a large clearance under a vehicle and typically large vehicles are utilised. Provision of such a ladder will allow for easy access of an operator to the vehicle, but also allow for complete retraction of the ladder out of the way of any earth moving operations.

It will be understood that there are other applications for the device other than as a ladder. For instance, other access devices such as conveyor belts, etc., may be utilised on the access device to provide for easy access between a substrate and an elevated S 10 surface.

Whilst a particular embodiment of the access device has been hereinbefore described, it will be understood that numerous variations and modifications to such an access device will be envisaged by persons skilled in the art. All such variations and modifications should be considered to fall within the scope of the invention as hereinbefore described, and as hereinafter claimed.

p:\wpdocs\amld\475250.ihd\ajc

Claims (4)

1. A retractable access device for providing access between a substrate surface and an elevated surface of a vehicle, comprising, support means attached to or integral with said elevated surface, said access device including a pair of spaced first and second side members connected by a plurality of spaced steps extending from a lower end of said access device to an upper end thereof, a pair of rigid arms provided on each side member of said access device, each arm being pivotally connected at a first end thereof to said support means, and, at second end thereof to said side members, said first end of said first arm being pivotally connected to said support means at a more upwardly and rearwardly position relative to said first end of said second arm, and, said second end of said first arm being pivotally connected to a more upward position on said respective side member relative to said second arm, whereby, said device is pivotally movable from a stable lower position to a stable :upper position, wherein, in said lower position, said access device is inclined at between 60° and relative to a substantially horizontal substrate surface, and, said upper end of said access device is positioned substantially adjacent to and forwardly of said elevated surface, and, wherein, in said upper position, said access device is positioned substantially vertically or at a rearwardly inclined angle in a position which is upward and rearward of said elevated surface. i 25

2. An access device as in claim 1, wherein one or both of said arms is provided with at least one dogleg bend therealong,

3. An access device in claim 1 or 2, wherein said access device further comprises an arm support rail disposed adjacent at least oale of said members. 16980Tcd

4. An access device as claimed in any one of claims 1 to 3, wherein said access member is inclined at approximately 620 relative to a substantially horizontal substrate surface. An access device, substantially as herein described with reference to the accompanying drawings. DATED this 3rd day of July 1996. HEDWELD ENGINEERING PTY LIMITED By Its Patent Attorneys DAVIES COLLISON CAVE e a.. e o e 16980\hed ABSTRACT An access device, such as a ladder, which is retractable, to provide access between a first position, and a second (retracted) position. The access device is provided with a pair of arms and each pivotally connected at pivots (10) and (11) to a support means, and, to the access member at pivots (12) and The device is configured such that the access member may be retracted whilst maintaining the second end of the access member elevated relative to the first end of the access member The arms and are preferably provided with one or two dogleg bends therein, to facilitate a totally retracted storage position. (Fig. 8). p:\wpdcsamd\475250.hed\ajc