GB2175948A

GB2175948A - Step ladder

Info

Publication number: GB2175948A
Application number: GB08514066A
Authority: GB
Inventors: Brian Weston
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-06-04
Filing date: 1985-06-04
Publication date: 1986-12-10
Also published as: GB2175948B; GB8514066D0

Abstract

A step ladder 1 has two pivotable sections 2,3, pivotable relative to one another about axis A, and an interconnecting standing platform 4. A tray or work platform 5 extends parallel to the platform 4 without overlapping the platform so that the whole length of the platform is available for unobstructed standing thereon. Platform 4 is pivotable about axis C and attached to section 3 by way of pivotable U-shape supporting member 12. A bridge piece of member 12 supports the free edge 4c of platform 4, member 12 is pivotally connected to section 3 at axis D and pivotally connected to the underneath of platform 4 at side edges 4d. <IMAGE>

Description

SPECIFICATION Step ladder This invention relates to a sfep'iadder having two sections pivotable relative to one-another and an interconnecting standing platform, which together define a trianguiar shape, when the ladder is in an open position ready for-use and when viewed from the side. Such a step ladder is hereinafter referred to as of "the type specified".

The standing platform will normally be some distance above the ground so that such a step ladder may be described as being of generally "A" form.

It is an object ofthe present invention to provide a step ladder having one or more improved features over other designs.

According to a first aspect ofthe present invention there is provided a step ladder of "the type specified" comprising a tray or work platform, such that, when the ladder is arranged on a horizontal support surface and in an open ready for use position also with the tray or work platform ready for use, said tray or work platform is arranged above the standing platform without horizontal overlap therebetween and/orthe length ofthestanding platform free from horizontal overlap with the tray or work platform is greaterthan 1' (30.5 cm) and, preferably, in the range 1(30.5 cm)to 2'-(61 cm).

Bythis aspect of the present invention the tray or work platform may be positioned or positionable beyond the standing platform so thatthe whole length ofthe standing platform (distance between the pivotable sections along the platform) is readily accessible for standing on without physical our visual obstruction. Alternatively, there may possibly be some horizontal overlap between the standing platform and the tray/work platform but there is at least a 1' (30.5 cm) length of standing platform (i.e. measured in a direction along the platform between the pivotable sections) free from such overlap and accessible for unobstructed standing thereon.Usuaily, thetray or work platform will be in a plane generally above and parallel to a plane occupied bythe standing platform, when the step ladder andtray/work platform are in their positions ready for use.

Preferably, the tray or work platform is pivotable on a first one of said sections and may be locked into its ready for use position and released therefrom so that the step ladder can be folded up neatly withoutthe tray causing obstruction. Additionally, or alternative- ly,thetray may be detachable from the remainder of the step ladder.

In one embodiment of the present invention a handrail is provided which supports (and which may define in part) thetray orwork platform and the handrail is pivotable with said tray or work platform.

Stays are provided which are connected orconnectible between the tray/work platform or handrail and said first section to fix the position of the tray/wdrk platform, said tray/work platform being pivotable once said stays are released from locking engagement with the first section and/or with the tray/work platform or handrail.

Conveniently, the handrail is tubular and of U-shape and the handrail, preferably, does not overlap the standing platform when the tray/work platform is ready for use thereby leaving the whole area ofthe standing plafform unobstructed. Also, preferably, the handrail does not extend beyond the transverse extent of said two pivotable sections (i.e. in a direction parallel to the width of the standing platform) in order to provide a neat safe structure.

Advantageously, the tray/work platform and hand rail may extend a distance of 20" (50.8 cm)fromthe apexofsaidtriangularshapeina horizontal plane and the free end of the tray/work platform, preferably, lies vertically above the foot of the first section in said open position ofthe ladderto provide a very stable structure in use.

The step ladder may have other advantageous design features which are relevant to the overall stable structure and accessiblity to the standing platform.

Such features will be self evident from the remainder ofthis specification. For example, each ofthe two pivotable sections may be ladder sections, the length of the standing platform may be 2' (61 cm), the triangle shape may be an isosceles triangle (giving a very stable structure), and the standing platform may be 2' (61 cm)from thefloorwhenthestep ladder is in the open ready-for-use position.

It is possible that more than one tray or work platform may be provided or more than one handrail be provided. The standing platform may be of adjustable height on the step ladder.

The step ladder may be provided with any of the features from the following statements of invention.

According to a second aspect of the present invention there is provided a step ladder of "the type specified" in which one end of the standing platform is pivotally connected to a first one ofsaid sections and the standing platform is pivoted relative to the second of said sections by way ofa supporting member which is pivotally mounted on said second section to be pivotable about a first axis, said supporting member being pivotally mounted on the standing platform to be pivotable about a second axis parallel to said first axis, and, when the ladder is in an open position ready for use, the supporting member supports, from underneath the standing platform, an end ofthe standing platform lying opposite said one end.

The supporting member is, preferably, of U-shape and advantageously may be an integral bracket.

Conveniently, the supporting member is pivotally mounted on the standing platform ata position intermediate the ends ofthe platform and preferably adjacent to the central transverse axis ofthe platform.

In one embodiment ofthe present invention the supporting memberwill substantially entirely underlie the standing platform and will directly supportthe common overlying area ofthestanding platform (for example a free edge of said opposite end and part of the side edges of the platform extending from the second pivot axis). Such an arrangement will, advan tageously, considerablyaid the overall stability ofthe structure and may provide support underneath, preferably,at least half ofthe length ofthe standing platform.

Hitherto, other step ladder designs may have had a standing platform supported atone end by a fixed rungsupportwhich onlysupportsthefree end edge of the standing platform. Clearly this is a much weaker structure than providing support underneath, for example, at least half the length ofthe standing platform.

Astep ladder in accordance with said second aspect ofthe present invention may include other advantageous design features apparent from the other parts ofthis specification.

Further according to the present invention there is provided a step ladder of the type specified comprising or including one or more of the following featu res:- a) the pivotable sections and standing platform togetherdefine an isoscelestriangleshape,when the ladder isin an open position- ready for use and when viewed from the side, b) said sections are both ladder sections with access to the standing platform being from each ladder section and from each end of said platform, c) said sections are substantially identical to one another, d) a detachable tray or working platform, which is, preferably, pivotable on a first one ofthe sections, which tray may perhaps be designed to be clipped or snapped onto oneofthe pivotable sections, e) the standing platform is art a height of 2' (61cm)- above the ground and two additional, lower step levels are-provided, f) one s-tep level is provided atwhich the standing platform is supported, -g)twdstep levelsare provided and the standing platform-is located at the second (higher) step level, h) four step levels are provided and the standing platform is located atthefourth (highest) step level, i) five step levels are provided and the standing platform is located at the fifth (highest) step level, j) the length (distance) between the pivotable sections along the standing platform) of the standing platform which is accessible for unobstructed standing thereon is greater than 1'(30.5 cm), and preferably greater than 1'6" (45.7 cm), k) the standing platform of feature j) in which the length of the platform lies in the range 1' to 2' (30.5 cm to 61 cml, I) the-included angle between said sections (apex angle of triangle) is about 34 + 3 , or at least greater than, 26 , or in the range 26 to 34 #3 , m) a tray of working platform is provided which extends horizontallyfrom theapex angle ofthe triangle for a distance of about20" (50.8 cm), n) said two pivotable sections flare outwardlyto the ground, preferably, from just below the level ofthe standing platform, o) the height ofthe standing platform is adjustable, preferably, slidably adjustable, on the step ladder, p)thewidthofthestandingplatf;orm is greaterthan 14" (35.6 cm) and is, preferably, 12" (38.1 cm), q) a tray orwork platform is supported in a horizontal plane by inclined stays releasably mounted on a firstone ofthe sections, said trayorworking platform being pivotable once said stays are released frqm the locking engagementwith said first section, r) footguard side walls are provided adjacentto the standing platform, s) a handrail which is preferably, detachable from the step ladder and/or, preferably, pivotable.

An embodiment of a step ladder in accordance with the present invention will now be described, bywayof example only, with referenceto the accompanying simplifieddrawingsin which: FIGURE 1 shows a perspective view of the step ladder in an open position ready for use, FIGURE 2 shows a perspective view ofthe step ladder in which the ladder is partially open, FIGURE 3 shows a rearview ofthe step ladder, FIGURE4shows aside view ofthe step ladder, and FIGURE 5 shows a view similar to FIGURE 2 in which some features have been modified.

FIGURES 1 to 4 show a step ladder 1 of "the type specified" having two sections 2, 3, pivotable relative to one anotherabout axis A, and an interconnecting, generally rectangular, standing platform 4. Sections2, 3 and platform 4together defineatriangular shape when viewed from the side, (in direction of arrows in FIGURE 1) whenthe ladderis in an open readyforuse position i.e. in the position as shown in FIGURE 1, As shown in FIGURE 1 the standing platform 4is about2' (61 cm) from ground level,the ladder-being of generally "A" form.

A tray or work platform 5 is supported and defined in part by a handrail 6. The handrail 6 is formed from tubular metal and is of U-shape.

The tray/work platform 5 is ready for use and extends in a horizontal plane generally above and parallel to the plane occupied by the standing platform 4 without any horizontal overlap-between the tray/work plat- form 5and standing platform 4. Therefore, the whole length 4a of the platform 4 is available for unob- structed standing thereon.Edge 5a of the tray 5 is directly vertically above edge 4b ofthe platform 4 as shown (or possibly may befurther horizontally outwarfftherebey6nd)-so that edge 4b may be seen easilyfrom a substantially vertial position above the level of the tray/work platform So that there is no visual obstruction to the standing platform 4 enabling the userto advantageously, clearly see the edge 4b on which he may be standing to enable full use and - confidence in using the entire length ofthe-standing platform 4.

The tray/work platform 5 is locked in its position~ ready for use, for example to receive tools and other utensils, paintpots and such like ata convenient horizontal and vertical location relafive to the user.

Since there is no overlap between the tray/work platform 5 and platfdrm 4the user has a large standing area withe good degree of movement giving good all-round balance and confidence to the user.

The tray is pivotable about axis B on section 2 on; bolt pins 7 extending through mounting brackets 8 which are rivetting on the top of section 2; after pair of rigid stays 9, connected between the handrail 6 and section 2 are released from locking engagementwith said section.-As-shown the lower curved ends ofthe stays 9a are releasably retained in matching holes in section 2 and can fairly easily be removed therefrom simply by pulling outwardly on the lower portions of the stays. The uppercurved ends 9b ofthe stays 9 are pivotally retained in matching holes in the handrail 6 by retaining push-fit caps (not shown for ease of illustration).The ends 9a ofthe stays 9 can be released from section 2 so thatthe tray/platform 5 and handrail 6 pivot in the anti-clockwise direction (downwards) about axis Bsothatthestep ladder 1 can befolded up neatly into a substantially flat condition (see FIGURE 4). Thetray/platform 5 and handrail 6 may be completely detachable from the brackets 8 simply by unscrewing the bolt pins 7. In an alternative embodimentthe stays 9 may be completely removable from the remainder of the step ladder.

Advantageously, the handrail 6 itself does not overlap the standing platform 4 as shown in FIGURE 1, leaving the whole area of the platform 4 unobstructed.

Additionally, the handrail 6 does not extend beyond the transverse extent of sections 2 and 3 (i.e. in a direction parallel to the width 4b ofthe platform 4; see FIGURE 3). Instead, the parallel handrail portions are no widerthan the limbs 2a, 2b ofthe section 2 (orthan limbs 3a, 3b of section 3) and in the folded position of the ladder will rest thereon. The tray/work platform 5 and handrail 6 extend in a horizontal plane a distance of 20" (50.8 cm) from the apex Y ofthe step ladder so that edge 5b of the tray/work platform 5 is vertically above the foot 2c of section 2, thereby providing a stable, safe structure.

As shown, each ofthetwo sections 2,3 are substantially identical ladder sections having step rungs 2d, 2e, 3d, 3e, and sections 2,3 flare outwardly towards the foot ofthe section 2c, 3cto increase overall stability.The triangular shape defined by limbs 2a, 3a with platform 4 is an isosceles triangle to give seemingly maximum stabilityforchosen length of standing platform at a chosen height above ground and in this instance, with platform 4 at a heightof2' (61 cm) abovethe ground,the apecangle is 34 In an alternative embodiment it is envisaged that the platform 4 may be provided at a different height and the ladder 1 may be provided for example with 1,2,4 or 5 step levels instead of with the 3 step levels as shown. However, it is envisaged that the same platform 4 may be used at these different levels which will thereby alterthe apex angle.

In factthetooling requirements forthis particular design arevery advantageous so thatthe platform may be provided at varying height levels to meet different commercial and/or domestic requirements.

Although not shown, a platform may be provided which is adjustable in height (perhaps slideably adjustable on limbs 2a, 2b, 4a, 3b) in a mannerwhich should be readily envisaged.

In this embodiment the standing platform is pro videdwith a guard plate 10 having upstanding guard side walls 10a adjacent to the platform 4to aid in retaining the feet of a user in a correct or safe standing position on the platform 4.

Ladder sections 2 and 3 are articulated by brackets 8 and brackets 11 as shown which are linked by pins p to define pivoting axis A.

Most advantageously, and most importantly, the step ladder 1 is provided with a pivotable supporting member 12 (as best shown in FIGURE 2). The member 12 isofU-shape and isformed as an integral unit.

One end 4b ofthe platform 4 is pivotally connected to section 2 to be pivotable about axis C arranged transverse of the platform 4 and platform 4 is pivoted relative to section 3 by way of member 12 which is pivotally mounted to limbs 3a, 3b of secion 3 by pivot bolts to be pivotable about an axis D (a first axis). The free ends ofthe U-shape of member 12 are connected to respective sides of the platform 4 by angle pieces 13 and pivot bolts so thatthe member 12 is also pivotable about axis E (a second axis) which is parallel to axis D.

Member 12 is pivotally mounted on the platform 4 at a position intermediate the ends of the platform adjacent to the transverse axis of the platform and substantially entirely underlies said platform. The common overlying area of the platform 4 may be supported and as shown the bridge piece 1 2a of member 12 supports a free end edge 4c of platform 4 (arranged opposite end edge 4b) and directly contacts this edge as shown in FIGURE 1. Halfofeach side edge 4d, 4e is supported by a respective parallel portion 12b, 1 2c of member 12 and as shown portions 12b, 1 2c, advantageously, do not extend beyond the transverse extent of platform 2. The end edges 4b, 4c and side edges 4d, 4e have bent or folded back lips L for safety reasons.The support member 12, therefore, gives very good support indeed to the platform 4 and, of course, such support is advantageous, owing to at least in part the length ofthe platform 4. The structure may lack the required degree of stability if, for example, only the end edge 4cwere directly supported and this may possibly lead to a disadvantageous bending or snagging of the platform 4 after some use. Additionally, the pivoting support member 12 enables the structure to be quickly and neatly folded up or opened outwhilst providing a good, solid stablesupportforthe platform.

The steps 2d, 2e, 3d, 3e and/or platform 4may be provided with a textured surfaceforgrip and, apart from rubber or plastics grip caps 14, on the ends of limbs 2c, 3cthe remainder of the step ladder may be fabricated entirely from suitable metals, for example, aluminium or steel.

Figure 5 shows a modified embodimentcorresponding to FIGURE 2 and the guard plate 10 has been omitted from this embodiment. The brackets 8 and 11 have now been replaced by two brackets bwhich are, perhaps, saferfor reasons which should be self evident and in any event provide a neater and once again, perhaps stronger, overall structure.

Angle pieces 13 have been omitted and as a cost effective alternative the support member 12 is bolted directly to cut and bent down portion of side lips L.

The step ladder in accordance with the present invention provides many improvements in stability and appearance, particularly where it is desired to have a standing platform of relatively large length or area and yet still maintain a reliable, stable structure.

It is further envisaged that two or more step ladders may be advantageously employed with a plank extending across the standing platforms to provide an extended walkway ata suitable height, for example, for use in decorating ceilings.

The scope ofthe present invention should not be unfairly limited by the choice of particularterminology employed and it isto be understood that particular terms should extend to the use of common generic terms where sensible. Additionally, individualfea- tures or particular combinations ofindividualfea- tures, orfunction orfunctions appertaining thereto, (for example the pivoting support member itself) may be individually patentably inventive in their own right.

Claims

1. A step ladder of "the type specified" comprising a trayor work platform, such that,when the ladder is arranged on a horizontal support surface and in an open ready for use position also with the tray orwork platform ready for use, said tray or work platform is arrangedabovethestanding platformwithouthori- zontal overlap therebetween and/orthe length ofthe standing platform free from horizontal overlap with the tray orwork platform is greaterthan 1' (30.5cm).

2. Astep ladder as claimed in Claim 1 in which said length free from overlap lies in the range 1 ' (30.5 cm) to 2' (61 cm).

3. Astep ladder as claimed in Claim 2 in which said length free from overlap is 1'6" (45.7cm).

4. Astepladderasclaimed in any one of the preceding claims in which thetray orwork platform is in a plane generally above and parallel to a plane occupied bythe standing platform, when the step laddertray/work platform are in theirpositions ready for use.

5. Astep ladder as claimed in any one of the preceding claims in which thetrayorwork platfo rm is pivotable on a first one of said sections and is lockable into its ready for use position and releasabletherefrom.

6. A step ladder according to any one ofthe preceding claims in which the tray is detachablefrom the remainder ofthe ladder.

7. Astep ladder as claimed in any one of the preceding claims in which a handrail is provided which supports (and which for example defines in part) thetray or work platform and the handrail is pivotable with said tray orwork platform.

8. Astep ladder as claimed in Claim 7 in which stays are provided which are connected or connectible between the tray/work platform or handrail and said first section to fix the position ofthe tray/work platform, said tray/work platform being pivotable once said stays are released from locking engagement with the first section and/orwith the tray/work platform or handrail.

9. A step ladder as claimed in Claim 7 or Claim 8 in which the handrail its tubular and of U-shape.

10. Astep ladder as claimed in Claim 9 in which the handrail does notoverlapthestanding platform when the tray/work platform is ready for use thereby leaving thewhole area ofthe standing platform unobstructed.

11: Astep ladder as claimed in any one of Claims 7 to 10 in which the handrail does not extend beyond the transverse extent ofsaid two pivotablesections (i.e. in a direction parallel to the width ofthe standing .platform).

12. A step ladder as claimed in any one of Claims 7 toll inwhichthetray/workplatform and handrail extends a distance of 20" (50.8cm) from the apex of said triangular shape in a horizontal plane.

13. Astep ladderas claimed in one of Claims 7to 12 in which the free end ofthetray/work platform lies vertically above the foot ofthefirst section in said open position ofthe ladder.

14. Astep ladder as claimed in any one ofthe preceding claims in which each ofthe two pivotable sections are ladder sections.

15. A step ladder as claimed in any one ofthe preceding claims in which a pivotable support membey is provided on one of said sections which is connected to, and which supports from underneath, the standing platform.

16. Astep ladder as claimed in any one ofthe preceding claims in which the standing platform is 2' (61cm) from thefloorwhen the step ladder is in the open ready-for-use position.

17. A stepladder as claimed in any one ofthe preceding claims in which morethan one try or work platform is provided or more than one handrail is provided.

18. A step ladder as claimed in any one ofthe preceding claims in which the standing platform is of adjustableheightonthestep ladder.

19. A step ladder as claimed -in any one ofthe preceding claims in which the pivotable sections and standing piafform togetherdefine an isoscelestriang- le shape, when the ladder is in an open position ready for use and when viewed from the side.

20. Astep ladder as claimed in any one ofthe preceding claims in which said sections are substantially identical to one another.

21. A step ladder as claimed in any one ofthe preceding claims in which one step level is provided at which the standing platform is supported.

22. A step ladder as claimed in Claim 21 in which two step levels are provided and the standing platform is located atthe second (higher) step level.

23. A step ladder as claimed in Claim 22 in which three step levels are provided and the standing platform is located atthethird (highest) step level.

24. A step ladder as claimed in Claim 23 in which fourstep levels are provided and the standing platform is located atthefourth (highest) step level.

25. A step ladder as claimed in Claim 24 in which five step levels are provided and the standing platform is located at the fifth (highets) level,

26. Astep ladderas claimed in anyone ofthe preceding claims in which the included angle between saidsections (apexangleoftriangle) is about34" + 3 , or at least greaterthan 26 , or in the range 26 to 340 + 3o.

27. Astep ladder as claimed in any one ofthe preceding claims in which said two pivotable sections flare outwardly to the ground, for example, from just belowthe level of the standing platform.

28. A step ladder as claimed in any one ofthe preceding claims in which the width of the standing platformisgreaterthan 14" (35.6cm).

29. Astep ladderas claimed in Claim 28 in which the standing platform width is 15" (38.1cm).

30. A step ladderas claimed in Claim 29 in which foot guard side walls are provided adjacent to the standing platform.

31. A step ladder of "the type specified" in which one end of the standing platform is pivotally con erected to a first one ofsaid sections and the standing platform is pivoted relative to the second of said sections by way of a supporting member which is pivotally mounted on said second section to-be pivotable about a first axis, said supporting member being pivotally mounted on the standing platform to be pivotable about a second axis parallel to said first axis, and, when the ladder is in an open position ready for use, the supporting member supports, from underneath the standing platform, an end ofthe standing platform lying opposite said one end.

32. Astep ladder as claimed in Claim 31 in which the supporting member is of U-shape.

33. A step ladder as claimed in Claim 32 in which the supporting member is an integral bracket.

34. Astep ladderasclaimed in any one of claims 31 to 33 in whichthe supporting member is pivotally mounted on the standing platform at a position intermediate the ends ofthe platform.

35. Astep ladder as claimed in Claim 34 in which said intermediate pivotal mounting is adjacent to the central transverse axis ofthe standing platform.

36. A step ladder as claimed in any one of Claims 31 to 35 in which the supporting memberwill substantially entirely underlie the standing platform and will directly support the common overlying area ofthe standing platform (for example a free edge of said opposite end and part ofthe side edges ofthe platform extending from the second pivot axis).

37. A step ladder as claimed in Claim 36 which provides support underneath at least half of the length ofthestanding platform.

38. A step ladder substantially as herein described and illustrated with reference to FIGURES 1 to 4 of the accompanying drawings or when modified substan tially as shown in FIGURE 5 of the accompanying drawings.

39. Astep ladder as claimed in Claim 31 and having a supporting member substantially as shown in FIGURE 5 of the accompanying drawings.

Amendments to the claims have been filed, and have the following effect: New claims have been filed as follows:-

40. A step ladder of "the type specified" in which one end ofthe standing platform ispivotallycon- nected to a first one of said sections and the standing platform is pivoted relative to the second of said sections by way ofa supporting memberwhich is pivotally mounted on said second section to be pivotable about a first axis, said supporting member being pivotally mounted on the standing platform to be pivotable about a second axis parallel to said first axis, and, when the ladder is in an open position ready for use, the supporting member supports, from underneath the standing platform, an end ofthe standing platform lying opposite said one end, the second mentioned end resting on the supporting member.