NZ535627A

NZ535627A - Ladder support

Info

Publication number: NZ535627A
Application number: NZ53562705A
Authority: NZ
Inventors: David Laurance Drury; Leigh Michael Nye
Original assignee: David Laurance Drury; Leigh Michael Nye
Priority date: 2005-03-27
Filing date: 2005-03-27
Publication date: 2006-12-22
Also published as: WO2006104395B1; WO2006104395A1

Abstract

A ladder support including; a support bracket adapted to engage with at least one support surface, and a prehensile connector adapted to engage with a single rung of a ladder, said connector defining a receiving cavity with a mouth and a main body, wherein the span of said mouth is less than the diameter of a rung to which the connector is to be engaged, said connector being formed from a resilient material.

Description

535 627 PATENTS FORM NO. 5 Appln Fee: $250.00 James & Wells ref: 31521/57 PATENTS ACT 1953 COMPLETE SPECIFICATION LADDER SUPPORT WE, David Laurance Drury, a New Zealand citizen of 245 Upland Road, RD 2, Katikati, New Zealand and Leigh Michael Nye, a New Zealand citizen of 10a Robinson Street, Katikati, New Zealand do hereby declare this invention to be described in the following statement: 1 James & Wells ref: 31521/57 LADDER SUPPORT TECHNICAL FIELD This invention relates to an improved ladder support. In particular, the present invention may be adapted to provide a support for a ladder which can securely 5 locate and support weight placed on a ladder resting on a corner of a building or other uneven surface.

BACKGROUND ART Ladders are commonly used to provide access to various elevated areas of buildings for construction or maintenance purposes. The upper portions of the 10 ladder styles or rungs are generally rested against and supported by a flat surface. However, in some instances, it is preferable to have a ladder located near a corner or some other form of uneven surface. In these instances, it is difficult to locate the upper section of a ladder in place while still providing the ladder with stability when supporting the weight of a user.

One attempt to address this safety concern is disclosed in Canadian Patent Filing No. 2,288,437. This patent specification describes a removable supporting bracket assembly to be connected to the upper rungs of a ladder wherein the support bracket provided has a substantially 'V' shaped form. The v-shape support is rested against a right angle corner of a structure where weight or load placed on 20 the ladder is transferred evenly through the support onto the corner surface of the structure. The support disclosed in this Canadian patent specification employs two independent and separate connectors to connect the support to two separate ladder rungs. Two relatively loose open sleeve-like connectors are slotted over two adjacent rungs. With the support described, two connectors are required to 25 prevent slipping or rotation of the support when a ladder is loaded and hence being 2 James & Wells ref: 31521/57 dislodged from its connection with the corner of the structure.

The requirement for two independent and separate connectors in these types of ladder supports provides complications and disadvantages. Including the need for a relatively large, heavy and cumbersome support design which makes the support 5 difficult to transport, store and cumbersome to install. Furthermore, additional materials are required to implement the second connector, which can increase the overall manufacturing cost of the support.

A further ladder support device is described in Great Britain Patent Application 2,267,113. This device employs the same 'V' shaped support bracket but uses two 10 hook connectors for attaching to the upper rungs of a ladder. This device is not only cumbersome, but also inconvenient as the hook connectors may slip off the ladder rungs when the ladder is being carried horizontally or inverted.

An improved ladder support which addressed any or all of the above issues would be of advantage. In particular, a ladder support which could function effectively 15 and safely with a connection to a single ladder rung only would be of advantage over prior art systems.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their 20 authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

It is acknowledged that the term 'comprise' may, under varying jurisdictions, be 3 James & Wells ref: 31521/57 attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning - i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components 5 or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process.

It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

Further aspects and advantages of the present invention will become apparent 10 from the ensuing description which is given by way of example only.

DISCLOSURE OF INVENTION According to a first aspect of the present invention there is provided a ladder support which includes; a support bracket adapted to engage with at least one support surface, 15 and, a prehensile connector adapted to engage with a single rung of a ladder, said connector defining a receiving cavity with a mouth and a main body, wherein the span of said mouth is less than the diameter of a rung to which the 20 connector is to be engaged.

Preferably the main body of the cavity has at least one interior surface adapted to contact a rung when said rung is inserted into the receiving cavity.

Preferably the span of the cavity is less than or equal to the diameter of a rung to 4 James & Wells ref: 31521/57 which the connector is to be engaged.

Preferably said prehensile connector is formed from a resilient material. The use of resilient materials allows the connector or portions thereof to be deformed while being engaged with a ladder rung and then to subsequently move back, or be 5 inclined to do so, into their original form, shape or dimensions once the rung involved has been engaged. The constricting force applied by the resilient connector attempting to return to its original form creates a frictional engagement with the rung that inhibits movement of the connector.

As aforementioned, existing ladder support devices have a major disadvantage in 10 that they require attachment to two rungs of the ladder to provide sufficient stability. This necessarily requires the provision of a bulky and cumbersome support as well as larger manufacturing costs and complexity.

The present invention overcomes this problem by providing a ladder support with a prehensile connector that is inhibited from rotation about the rung to which it is 15 engaged. When the support is engaged with a rung it can thus extend out from the ladder to engage with a support surface or surfaces while being inhibited from rotation about the rung to which it is connected, and thus reduce the likelihood of possible slipping of the ladder support over the support surface. This allows the support surface involved to support the weight of any load placed on the ladder 20 when used while inhibiting movement of the ladder.

In preferred embodiments the support bracket is adapted to engage with the two support surfaces formed by two walls of a corner of a structure or building. Preferably a support bracket with a substantially 'V' shaped configuration is used to engage with the pair of support surfaces formed by the corner, thereby allowing a 25 ladder to be safely propped up by the corner. Preferably the interior angle of the 'V' is substantially 90° to correspond to the corner wall sections of typical buildings.

James & Wells ref: 31521/57 Reference throughout this specification will be made to the bracket having a substantially 'V' shaped configuration and being adapted to engage with a substantially right angled corner of a structure. However, those skilled in the art should appreciate that various other forms of brackets which need not necessarily 5 engage with corners (or in particular right angled corners), may be provided in conjunction with the present invention and reference to the above only throughout this specification should in no way be seen as limiting.

In a further preferred embodiment, the connector of the support provided may be formed from a resilient plastic material. Plastic materials can be produced at 10 relatively low cost and can also exhibit sufficient structural strength and resilience to function effectively as a connector in conjunction with the present invention.

The mouth of the receiving cavity provides an open aperture to give access to the receiving cavity. In use, a rung of a ladder may be engaged with such a connector by being passed through the mouth of the receiving cavity into the main body. In 15 some embodiments, the diameter of the receiving cavity's mouth may be less than the diameter of a rung to which the connector is to be engaged. In such embodiments the resilient nature of the connector can be employed to force open the receiving cavity's mouth to a diameter slightly greater than that of a rung to be engaged with the connector. The rung may then be inserted through the mouth 20 into the main body of the cavity and retained therein.

Preferably the diameter, configuration or dimensions of the cavity's main body may be such that at least one interior surface of the cavity contacts with, and is frictionally engaged with, a rung inserted into the cavity. Those skilled in the art should appreciate that raised edges or ridges on the exterior of the rung may be 25 frictionally engaged with the interior surface or surfaces of such a receiving cavity.

In one embodiment, the interior surface of the receiving cavity of the connector is 6 James & Wells ref: 31521/57 provided with a coating or attachment of resilient material (such as rubber or the like) to provide an enhanced frictional engagement with the rung. Preferably the resilient material is a Thermoplastic Elastomer (TPE) to provide reduced cost manufacturing relative to conventional rubber, i.e. TPEs are easily recycled, have a 5 relatively lighter density and can easily be self coloured. Furthermore, very little scrap wastage is produced in the moulding cycle as any scrap that is produced can be recycled.

In a further embodiment the diameter of the cavity may also be larger than the diameter of a rung to be received, the resilient material provided therebetween to 10 provide the frictional engagement.

In one embodiment, the interior surface of the cavity may include at least one protrusion or recess adapted to mate with the rung or portion thereof. In this way the ladder support is further secured to the rung and prohibited from rotation about the rung. For example; in one embodiment the interior surface may include a 15 plurality of longitudinal ridges that engage with longitudinal recesses on the rung of a ladder or vice versa.

The resilient nature of the connector may also take into account any minor variations in ladder rung diameter so that in some instances the connectors' receiving cavity body may be slightly deformed, stretched or enlarged when 20 engaged with a ladder rung.

This configuration of the connector allows variation in the cross section form or shape of a rung to be accommodated. The resilient nature of the connector can be employed to frictionally engage an interior surface or surfaces of a receiving cavity with, for example, circular, elliptical, triangular, rectangular or square cross section 25 ladder rungs depending on the diameter of the cavity provided. 7 James & Wells ref: 31521/57 Preferably the receiving cavity of the connector forms an elongate channel of constant cross-section. In a further embodiment, the connector has a partially annular lateral cross section, having a hollow centre forming the receiving cavity of the connector and a mouth extending about less than half the circumference of 5 said cavity. Thus, in such an embodiment the connector is particularly adapted to accommodate the tubular rungs of many common ladders. However, it should be appreciated that this is only one possible configuration and the connector may be manufactured to have any particular shaped lateral cross section to engage with a particular shaped ladder rung.

It should be appreciated that the prehensile connector may be formed from a single piece or from a plurality of discrete pieces, and reference throughout the specification to a single-piece connector should not be seen to be limiting. For example; in one embodiment the connector may include a plurality of sections, each attached to the support bracket and each adapted to engage with a single 15 common rung.

Preferably the support bracket is adapted to frictionally engage with the support surface(s), thus inhibiting movement of the bracket across same. Preferably the frictional engagement is achieved through the provision of frictional engagement members or coatings attached, or formed integrally with a surface(s) of the bracket 20 adapted to contact with said support surface(s). In preferred embodiments the frictional engagement members may include one or more, or a combination of: rubber or TPE pads or coatings; recesses or gratings; protrusions, bevels, ridges or the like; dimpled or roughened surfaces.

Preferably the portion of the ladder support connecting the bracket to the 25 connector includes a plurality of 'force-distributing' struts. Thus, when the ladder support is attached to a ladder and the bracket is engaged with a support surface, 8 James & Wells ref: 31521/57 any reactionary force incident on the bracket from the wall is redistributed by the struts symmetrically about the midsection of the connector.

Preferably the struts are laterally enlarged to provide enhanced structural rigidity and strength, while minimising weight. Thus, not only do these struts add structural 5 strength and rigidity to the support while minimising weight, they also aid stability by inhibiting any torque occurring about longitudinal axes of the ladder. In alternative embodiments the portion of the support connecting the bracket to the connector could be a simple solid 'block', albeit with an increase in the weight of the support.

According to another aspect of the present invention there is provided a method of supporting a ladder against a support surface using a ladder support as aforementioned including the steps of: engaging the connector of the ladder support to a rung of a ladder; and manoeuvring the ladder so that the support bracket contacts with the 15 support surface.

According to another aspect, there is provided a method of connecting a ladder support as aforementioned to a ladder by inserting a rung of the ladder into the receiving cavity of the connector.

The present invention thus provides significant advantages over prior art ladder 20 supports for example; ■ The use of a resilient connector substantially as described above allows a support to be constructed with a single connector only. The frictional engagement of such a connector's interior surface or surfaces within a receiving cavity can provide a strong connection to a single rung. This 9 James & Wells ref: 31521/57 connection can in turn prevent rotation or slipping of the connector's receiving cavity about a rung and therefore will allow the support bracket provided to be locked in place and make a fixed orientation angle with respect to a ladder.

■ The provision of a single connector only also reduces manufacturing costs and timeframes for such a ladder support, in addition to providing a compact support design which may be easily stored or transported, and installed on the upper end of a ladder.

BRIEF DESCRIPTION OF DRAWINGS Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which: Figure 1a Figure 1b Figure 1c Figure 2a Figure 2b Figure 2c Figure 3a shows a perspective view of a ladder support in accordance with a preferred embodiment of the present invention; shows a plan view of the ladder support shown in figure 1a; shows an end view of the ladder support shown in figures 1a and 1b; shows a perspective view of a ladder support as configured in accordance with a second embodiment of the present invention; shows a plan view of the ladder support shown in figure 2a; shows an end view of the ladder support shown in figures 2a and 2b; shows a perspective view of a ladder support in accordance with James & Wells ref: 31521/57 a third preferred embodiment of the present invention with frictional pads attached; Figure 3b shows a perspective view of the ladder support shown in figure 3a without the frictional pads attached; BEST MODES FOR CARRYING OUT THE INVENTION Figures 1 - 3 show views of two ladder supports (1) configured in accordance with three preferred embodiments of the present invention.

Each ladder support (1) includes a support bracket (2) attached to a single prehensile connector (3) of resilient material such as plastic, having a receiving 10 cavity (4) with a mouth (5) and a main body (6). The connector (3) forms an elongate channel with a constant semi-circular cross-section having a diameter substantially the same, or slightly less than, the diameter of a rung (not shown) to which the connector (3) is to be engaged. The span, or distance between opposing portions (5a, b), of the mouth (5) of the cavity (4) is less than the diameter of the 15 rung (not shown) to which the connector (3) is to be engaged, thereby preventing the rung from exiting the mouth (5) when engaged.

The main body (6) of the cavity (4) has an interior surface (8) adapted to contact the rung when the rung is inserted into the receiving cavity (4). The resilient properties of the connector (3) allow the rung to be forced through and past the 20 connector mouth (5) into the connector's (3) receiving cavity (4).

The diameter of the receiving cavity (5) is also configured to match the diameter and shape of the rung (4) to be received and engaged by the connector (3) thereby placing the interior surface (8) into contact with the rung. Preferably the diameter of the receiving cavity (4) is slightly smaller than that of the rung to be located so 25 the connector (3) firmly grips the rung. This enhanced frictional engagement 11 James & Wells ref: 31521/57 between the interior surface (8) of the cavity (4) and the associated contacting exterior surface of a rung stops the connector (3) from rotating about the rung. Thus, in use, the bracket (2), engaged with a rung, is locked in a fixed orientation with respect to the ladder involved.

The support bracket (2) has a substantially 'V' shaped configuration formed from two mutually perpendicular arms (2a, b) wherein each arm (2a, b) is orientated symmetrically at approximately 45° to the longitudinal axis of the connector (3).

As shown in figures 1a-b and 2a-b, five force-distribution struts (7) join the connector (3) to the bracket (2). Each strut (7) is connected at a first end to a 10 portion of the bracket (2) and at a second end to the connector (3). The struts (7) are laterally enlarged to provide enhanced structural rigidity and strength, while minimising weight. For example, in other embodiments the portion of the support (1) connecting the bracket (2) to the connector (3) could be a simple solid 'block' which means a relatively larger overall weight of the support.

When the ladder support (1) is attached to a ladder and the bracket (2) is engaged with a support surface, any reactionary force incident on the bracket (2) from the wall is redistributed by the struts (7) symmetrically about the midsection of the connector (3). Therefore, not only do these struts add structural strength and rigidity to the support (1) while minimising weight, but they also aid stability by 20 inhibiting any torque occurring about longitudinal axes of the ladder.

Figure 2 shows a support (1) with an alternatively shaped connector (3) adapted to engage with a rung with a rectangular cross-section such as can be found on many common ladders. As can be seen in figure 2c, the span of the mouth (5) is less than the distance between the adjacent walls of the cavity (4).

Figure 2a shows frictional engagement members in the form of rubber pads (9) 12 James & Wells ref: 31521/57 that contact the wall or support surface and inhibit sliding movement of the bracket (2) over same. Threaded recesses (10 shown in Figure 1a) are provided to facilitate attachment of the bracket (2) to the support surface or portion thereof e.g. the bracket (2) may be attached to a building, scaffolding or the like by screws 5 passed through the recesses and coupled to the building or scaffolding.

Figures 3a and 3b show a further preferred embodiment with laterally enlarged arms (2a, b) tapering outwardly towards the end of each arm (2a, b) distal to the connector (3). This enlargement helps to maintain stability of the bracket (2) against the support surface by providing a larger surface area in frictional contact with the support surface in comparison to a bracket with arms having constant lateral width.

Figure 3a also shows apertures (11) for releasable receiving coupling protrusions (12) of rubber or thermoplastic elastomeric pads (13) (as shown in figure 3b), enabling the worn pads (13) to be easily replaced.

The engagement configurations as aforementioned (shown in figures 1 - 3), permit the ladder support (1) to be attached to a single rung while still retaining its functionality as a stable ladder support that prevents rotational movement of the ladder about any longitudinal axis of same; thereby providing a simple, compact support that is relatively less expensive to manufacture than existing devices.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof. 13 James & Wells ref: 31521/57

Claims

A ladder support including; a support bracket adapted to engage with at least one support surface, and - a prehensile connector adapted to engage with a single rung of a ladder, said connector defining a receiving cavity with a mouth and a main body, wherein the span of said mouth is less than the diameter of a rung to which the connector is to be engaged, said connector being formed from a resilient material.
The ladder support as claimed in claim 1 wherein the main body of the cavity has at least one interior surface adapted to contact a rung when said rung is inserted into the receiving cavity.
The ladder support as claimed in claim 2 wherein the span of the cavity is less than the diameter of a rung to which the connector is to be engaged.
The ladder support as claimed in claim 2 or claim 3 wherein the interior surface of the connector includes at least one protrusion or recess adapted to mate with a ladder rung or portion thereof.
The ladder support as claimed in any of claims 1-4 wherein an interior surface of the receiving cavity of the connector is provided with a coating or attachment of resilient material.
The ladder support as claimed in claim 1 wherein the span of the cavity is larger than the diameter of the rung to be received, and the interior surface 14 James & Wells ref: 31521/57 of the receiving cavity of the connector is provided with a coating or attachment of resilient material.
7. The ladder support as claimed in any of the previous claims wherein said connector is formed from a plurality of discrete pieces.
8. The ladder support as claimed in any of claims 1-7 wherein said support bracket is substantially 'V' shaped.
9. The ladder support as claimed in any of claims 1-7 wherein said support bracket is substantially 'L' shaped.
10. The ladder support as claimed in any of the previous claims wherein the support bracket includes frictional engagement members, adapted to contact with said support surface.
11. The ladder support as claimed in claim 10 wherein the frictional members may include any one or more, or a combination of: rubber pads or coatings; recesses or gratings; protrusions, bevels, ridges or the like; dimpled or roughened surfaces.
12. The ladder support as claimed in any of the previous claims wherein the receiving cavity has a circular, elliptical, triangular, rectangular or square cross section.
13. The ladder support as claimed in any of the previous claims wherein a portion of the ladder support connecting the bracket to the connector includes a plurality of struts.
14. A method of connecting a ladder support as claimed in any of the previous claims, to a ladder, by inserting a rung of the ladder into the receiving cavity of the connector. 15 James & Wells ref: 31521/57 A method of supporting a ladder against a support surface using a ladder support as claimed in any of claims 1-13 including the steps of: engaging the connector of the ladder support to a rung of the ladder; manoeuvring the ladder so that the support bracket contacts with the support surface. A ladder support substantially as herein before described, with respect to, and as shown in the accompanying drawings. A method of connecting a ladder support to a ladder substantially as herein before described, with respect to, and as shown in the accompanying drawings. and DAVID LAURANCE DRURY and LEIGH MICHAEL NYE by their Attorneys JAMES & WELLS 16 James & Wells ref: 31521/57