GB2459562A

GB2459562A - Safety ladder construction

Info

Publication number: GB2459562A
Application number: GB0907216A
Authority: GB
Inventors: Neil Ernest Baglin
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-05-01
Filing date: 2009-04-28
Publication date: 2009-11-04
Also published as: GB0807913D0; GB0907216D0

Abstract

A safety ladder 1 having side stays 3, 6 held parallel by rungs 7, 4 where the upper end of the ladder has a means 34 which bear against the supporting surface and keep the side stay 6 ends from resting against the surface 32. The lower end of the ladder 1 has means adjustable both forward and back and side to side to accommodate the floor the ladder 1 stands on being uneven. The ladder 1 may comprise two sections linearly extendable with respect to each other. The lower ladder section may include a means 19 for holding the ladder at a required angle which may comprise a bar 21 mounted centrally on the lower section which pivots between a position in use and a storage position against the rungs. The feet 11 of the ladder may be adjustable vertically.

Description

LADDER CONSTRUCTION

This invention relates to the construction of ladders intended for use by persons who require to carry out an action, operation, task or the like at elevated levels.

It is an extremely common practice for work persons who require to carry out activities above ground level which activities in their view does not necessitate the erection of scaffolding or which requires action to be taken without the delays such as would arise from the assembly and erection of scaffolding and associated work platforms and in consequence resort to the use of a ladder.

In practice, such use not infrequently involves the mere leaning of a ladder against an appropriate/convenient support.

It is well known that a common reason for the use of a ladder resides in the fact that ladders are readily transportable by relatively small sized vehicles such as for example, cars provided with appropriate roof racks, short length vans provided with ladder mounting supports as compared with very much larger vehicles i.e., lorries that are 1 5 inevitably necessary for the transportation of scaffolding systems.

In practice, there are many situations in which the use of a ladder is perhaps the only appropriate means of gaining access to an elevated position, as a means of being able readily to move a work position from place to place as work activity proceeds An example of such ongoing movement arises when a work person is cleaning out a roof gutter. As is well known gutters in practice frequently fill with detritus washed down from a tiled roof, leaves, plant seeds that germinate and grow thereby leading to blockage of water flow Iengthways of the gutter, painting, repainting and so on to move a work position from place to place as a work activity proceeds.

Further frequent usage of ladders arises in the repainting of windows, the cleaning of windows and other operations involving frequent movements of a work position i.e., a work operation that is such that an actual work position is rapidly displaced for * -2-example lengthways of a gutter, or is displaced higher or lower when, for example, painting a window.

As a consequence of the extremely varied manners and modes of ladder usage it will be appreciated that the risk of accidents arising with the use of ladders is a real and highly complex situation in terms of the causes an d reasons for accidents occurring during the use of a ladder.

Since it is thus well known that the use of a ladder infrequently leads to accidents to a work person more and more health and safety regulations have in recent times been progressively introduced with a view to eliminating where feasible usage of a ladder in such manner as to involve the possible risk of accident to the user.

Unfortunately in spite of the ongoing exhortations by the authorities many users of ladders for various reasons fail to take the precautions advocated either through lack of knowledge or more regrettably as a result of users choosing to ignore the regulations.

1 5 Often in the case of the latter situation an underlying reason appears to reside in the fact that such persons have not equipped themselves with safety articles/devices associated with ladder safety or just do not bother to make sure that they are available.

it is an object of the present invention to facilitate the utilisation of safety devices intended to assist in the safer use of ladders.

According to a first aspect of the invention there is provided a safety ladder construction including side stays maintained in spaced relationship by rungs, wherein the upper most end of the ladder incorporates permanently mounted means co-operable with a surface against which the ladder is positioned for preventing the upper ends of the ladder stays from resting upon a surface against which the ladder is positioned, and wherein means are permanently mounted at the bottom end of the ladder for accommodating any unevenness of a surface upon which the ladder rests in both the front to rear direction of the ladder and the sideways direction of the ladder, upon which the ladder isrequired to stand.

In a further aspect of the invention a safety ladder construction incorporates at least two ladder sections each including side stays maintained in spaced relationship by rungs, the sections being inter-connectable for lengthways extension relative to each other, wherein the upper end of the section providing the upper most section of the ladder incorporates permanently mounted means co-operable with a surface against which the ladder positioned for preventing the upper ends of the ladder section stays from resting upon a surface against which the ladder is positioned, means permanently mounted at the bottom end of the ladder section providing the bottom section of the ladder with means for accommodating any unevenness of a surface upon which the ladder rests in both the front to rear direction of the ladder and the sideways direction of the ladder, upon which the lower section rests, A still further aspect of the invention provides a safety ladder construction incorporating at least two ladder sections each including side stays maintained in spaced relationship by rungs, the sections being inter-connectable for lengthways extension relative to each other, wherein the upper end of the upper most section of the ladder incorporates permanently mounted means co-operable with a surface against which the ladder is positioned for preventing actual contact between the upper most end of the ladder from resting upon a surface against which the ladder is positioned, and wherein means are provided at the lowermost end of the ladder for enabling accommodating any unevenness of a surface upon which the ladder rests in both the front to rear direction of the ladder and the sideways direction of the ladder, upon which the ladder isrequired to stand.

For a better understanding of the invention and to show how to carry the same into effect reference will now be made to the accompanying drawings in which:-Figure 1 is a front view of a ladder in usage standing position permanently incorporating features incorporating the concepts of the present invention; and Figure 2 is a side view of Figure 1, the ladder being illustrated when leaning against an upright surface.

Referring to the drawings the ladder 1 shown therein is of the extendible type includes a lower first section 2 comprising stays 3 and a series of regularly spaced rungs 4 that maintain the stays in spaced apart relationship and an upper second ladder section 5 that includes stays 6 maintained in spaced relationship by rungs 7.

In the embodiment shown the stays and rungs are formed from a metal such as aluminium in tubular or rectangular cross-section.

The upper ladder section 5 is so dimensioned so that its stays 6 can rest upon the rungs 4 of the lower ladder section 2 as to be lengthways displaceable relative to the lower section 2.

The upper end of the lower section 2 is provided with brackets 8 which are slidably 1 5 engageable with the stays of the upper section 5 so as to locate the upper ladder section 5 relative to the lower section 2 and also to hold the upper section in close contact with the upper part of the lower section at all times throughout any such relative length adjustment.

The upper section stays 6 in the vicinity of the lowermost rung 7A of this section are each provided with a hook like member 9 that is intended to engage with that rung 4 of the lower section 2 that is adjacent to the lowermost rung 7A of the upper section.

These hook like members 9 firmly hold the upper section lower end in firm engagement with the lower section whet ever the relative lengthways setting of the two sections 2 and 5.

It will be understood that the particular rung of the ladder section 2 that co-operates with the lowermost rung 7A of the upper section 5 and is thus engaged by the hook like members 9 will be determined by the relative positions of the two ladder sections and thus the overall length of the extended ladder 1.

As so far discussed the ladder 1 can be regarded as being a conventionally constructed extending ladder which historically has been the centre of many accidents involving ladders.

In accordance with the proposa's of the invention this basic extendible ladder construction is provided with a plurality of accessories/devices that are permanently mounted to the ladder sections.

For convenience these accessories will be considered in sequence in relation to their positioning lengthways of the ladder.

In relation to the lower section 5 of an extending ladder it is of extreme importance that the bottom of the lower section can be positioned and set into a firm and secure footing with the ground upon which the ladder stands.

Such firm footing can be regarded inter alia as involving several relatively distinct and 1 5 separate function requirements including establishing a firm grip between the bottom of the ladder stays and the ground, front to rear stabilisation of the lower section, adequate lateral stability, and attaining the ladder installation angle of inclination considered to be correct according to health and safety regulations.

These four factors will be considered in detail.

For the purpose of ensuring affirm grip with the ground the bottom ends 10 of the stays 3 are each provided with a high grip rubber foot 11. In relation to one of the stays (the right hand stay as can be seen in Figure 2) the foot 11 is pivotally connected to the lower end 12 of a bar 11 that issecurely fastened to the lower end of the right han dstay.

To enable level adjustment for the ladder the foot unit 11 associated with the other stay (the left hand stay as seen in Figure 2) is connected to the lower end of a level adjustment bar 14 telescopically engageable in the lower end 11 of the associated stay 2. The level adjustment bar is provided with a series of pin receiving holes 15 such that with the engagement of a pin 16 with a similar hole 17 in the stay bottom end and a selected one of the holes 15 the of the associated foot unit 11 the latter can be set to a required position relative to the associated stay such that the foot units accommodate lateral unevenness of the ground upon which the ladder 1 stands.

It will be noted from the Figures that the right hand stay is slightly longer than the left hand stay so as to facilitate required adjustment.

The foot units include a pivoted connection with the associated stays 3 and 6 to enable accommodation of any front to rear (relative to the ladder) slope of the ground.

Additionally this pivotal displacement of the foot units 11 enable adjustment of the working slope of the ladder 1 so that the bottom of the ladder can be so positioned relative to a wall or other upright surface against which the ladder is required to rest so that the working slope of the ladder can be more easily set at an acceptable angle in accordance with health and safety regulations. To assist in the setting of the working slope a spirit level 18 is mounted to the ladder. With such a spirit level when the ladder is positioned such that the spirit level is horizontal the ladder is set to the acceptable level. In practice the spirit level is so mounted that when the spirit level indicates the required level setting the ladder is set to an acceptable slope.

To enhance the sideways stability of the ladder the lower ends of the stays 3 are angled outwards relative to the remainder of the lower ladder section as shown in Figure 1. That is the bottom of the lower section 2 is wider than the remainder of the section. The splayed outwards sections of the stays are bridged by the lowermost pair of rungs 4. This splaying outwards lends lateral stability to the ladder.

It will be noted that the above mentioned bars 13 and 14 are suitably angled to accommodate the outward splaying of the bottoms of the stays 3.

In order to provide for front to rear stabilisation of the ladder the lower section is provided with a rear stabiliser unit 19. The stabiliser unit 19 includes a bracket 20 secured to the lower ladder section 2 centrally of the stays 3. A ladder stabiliser bar 21 is pivotally mounted to the bracket 20 such that the stabiliser bar 21 is pivotal between an in use position and a stowed position in which it folds flat against the rungs of the lower secton.

To accommodate any front to rear unevenness of the ground the unit includes a position adjustment bar 22 telescopically engageable in the bar 21. The bar 22 is provided with a series of holes 23 spaced lengthways of the bar. The bar 21 is provided with a bore 24. The position of the bar 21 relative to the bar 22 is set by the engagement of a pin 25 in the bore 24 and in a selected one of the holes 23. This selection of a hole 23 is related to the extent of levelling required.

In order to provide for additional safety and security in the setting of the lengthways positioning of the two sections, the upper section 5 is provided with means for locking the sections against relative displacement that could lead to disengagement of the hook members from engagement with a rung 4. As shown the means for locking includes a rung locking element 26 provided on the upper section. This element includes a shaped plate pivotally mounted to the right hand (as seen in the Figure 1) stay to be pivotal between a locking position in which it engages with both a rung 4 and a rung 7 in such manner that the thus engaged rungs are not relatively displaceable. The plate is held in its locking position by the tightening of a nut (not shown) serving when tightened to prevent movement of the plate.

At the upper end of the upper section there is provided a ladder stand-off unit 30 which serves to space the upper ends 31 of the stays 5 away from direct contact with a surface such as a wall 32 towards which the ladder leans.

The stand-off unit 30 includes a bar 33 extending transversely of the upper ladder section 5 to either side of the stays. The bar 33 mounts at each end thereof a further bar 34 that extends transverse to the bar 33. The free end of each such bar 34 mounts a rubber tired wheel/roll 35 that is intended to bear against the surface 32.

These rubber tired wheels/rolls 35 afford substantial lateral grip with the surface 32 whilst at the same time facilitating safer and easier raising and lowering of the ladder relative to the surface 32.

The space between the two bars 33 accommodates a support a tray (not separately shown) for receiving tools or other articles that a user of the ladder may require for use at the desired user working height.

The standoff unit also includes a user safety harness attachment point 35 to which a ladder user is able to connect a safety harness whilst working thereby obtaining additional security. The provision of such a harness attachment facility makes it possible for a ladder user to operate without it being necessary always to hand hold on to the ladder thereby limiting activity to single hand operations.

In addition in order to provide for additional working security of the ladder the lower section of the ladder is provided with a ladder tie-off connection 36 that can be used 1 5 to connect the ladder to an anchorage point 37 provided at a convenient location of the surface 32. This tie-off connection can include a strap 38 passing through the interior of a ladder rung and connecting with the anchorage point 37.

Whilst the forgoing description has been directed to lengthways extendible ladders it should be appreciated that the stand-off facility, the bottom levelling and anti-slip facility, the ladder tie off facility, the tool tray facility, the stabiliser arrangements and the safety harness facility can be provided upon fixed length ladders

Claims

CLAIMS.1. A safety ladder construction including side stays maintained in spaced relationship by rungs, wherein the upper most end of the ladder incorporates permanently mounted means co-operable with a surface against which the ladder is positioned for preventing the upper ends of the ladder stays from resting upon a surface against which the ladder is positioned, and wherein means are permanently mounted at the bottom end of the ladder for accommodating any unevenness of a surface upon which the ladder rests in both the front to rear direction of the ladder and the sideways direction of the ladder, upon which the ladder is required to stand.
2. A safety ladder construction ias claimed in claim 1, and incorporating at least two ladder sections each including side stays maintained in spaced relationship by rungs, the sections being inter-connectable for lengthways extension relative to each other, wherein the upper end of the section providing the upper most section of the ladder incorporates, permanently mounted means co-operable with a surface against which 1 the ladder is positioned for preventing the upper ends of the ladder section stays from resting upon a surface against which the ladder is positioned, permanently means mounted at the bottom end of the ladder section providing the bottom section of the ladder with means for accommodating any unevenness of a surface upon which the ladder rests in both in the front to rear direction of the ladder and in the sideways direction of the ladder.

3 A safety ladder construction as\claimed in claim 1, and incorporating at least two ladder sections each including side stays maintained in spaced relationship by rungs, the sections being inter-connectable for Iengthways extension relative to each other, wherein the upper end of the section providing the upper most section of the ladder incorporates permanently mounted means co-operable with a surface against which the ladder is positioned for preventing actual contact between the upper most end of the ladder from resting upon a surface against which the ladder is positioned, and wherein means are permanently provided at the lowermost end of the ladder for enab!ing levelling of the feet of the ladder to accommodate any unevenness of a surface upon which the ladder rests, and wherein means are permanently provided for offsetting possible slip of the ladder relative to the ground in both the front to rear direction of the ladder and in a sideways direction of the ladder, and means are permanently provided for enabling the establishment of a requisite angle of usage inclination for the ladder 4. An extendible safety ladder construction as claimed in Claim 2 or 3, wherein the means for enabling the establishment of a requisite angle includes a bracket secured to the lowermost ladder section centrally of the spacing of the stays and a ladder bar pivotally mounted to the bracket in such manner that the bar is pivotal between an in use position in which it is inclined to the ladder section and a stowed position in which it folds against the rungs of the ladder section, and wherein said bar serves additionally as a front to rear stabiliser for the ladder An extendible safety ladder construction as claimed in claim 2, 3 or 4, wherein for the purpose of providing an enhanced footing to the ladder the bottom stay ends of 1 5 the lowermost section of the ladder are each provided with a foot construction for providing a grip greater than that afforded by the bottom ends of the stays, and wherein each said foot construction is connected with its associated stay by way of pivotal connection so as to enable front to rear direction tilt relative to its associated stay to enable front to rear angular adjustment relative to the lower ends of the stays.6. A safety ladder construction as claimed in claim 5, and wherein each said foot construction is connected with its associated stay end by way of an adjustment arrangement enabling the foot to be set at selectable distances from the lower end of the associated stay, the arrangement being such as to enable each foot to be so relatively positioned to the associated adder stay end as to accommodate unevenness in the surface upon which the ladder stands and additionally to be able to accommodate differing angles of the setting the ladder to the vertical independently of the unevenness of the ground.7. A safety ladder construction as claimed in claim 1,2,3,4 5 or 6, and wherein the bottom end portions of each of the ladder stays of the lowermost ladder section is angled outwards relative to the remainder of the associated stay so that the bottom portion of the ladder is wider than the reminder of the ladder section.8. A safety ladder construction as claimed in claim 2, and claims 3 to 7 as dependent to claim 1, and including means for locking the ladder sections relative to each other when in relatively extended position.9. A safety ladder construction as claimed in any one of the preceding claims, and wherein a spirit level is provided on the ladder so as to provide a all times a visual indication of the slope/inclination of the ladder.9. A safety ladder construction as claimed in any one of the preceding claims, and wherein the attachment/fitting at the uppermost end of the ladder includes a structure including spaced rails connected to and projecting from the upper ends of the ladder section stay with the ends of the rails remote from the stays mounting 1 5 wheels positioned and dimensioned as to be engageable against which the latter is erected.10. A safety ladder construction as claimed in claim 9, and wherein the rails serve to support a tool tray.11. A safety ladder construction as claimed in any one of the preceding claims and including at the upper end of the upper section of the ladder a user safety harness connection point.12. A safety ladder construction, substantially as her em before described with reference to the accompanying drawings.