AU669908B2 - Ladder, kit and leaning support for ladders - Google Patents

Abstract

A ladder (1) is provided with a multi-purpose head (19) which may be fixed on the ladder by means of two transition pieces (101/101'). The head (19) has supporting paws (29) which allow not only the secure positioning of the ladder on straight wall faces, internal corners and external corners but additionally increase the security for the user. Additional bearing faces may be provided to allow stable support on ledge-like wall projections. Vertically and horizontally acting bearing faces are used for this purpose. The multi-purpose head may be fastened in a selectable height position on the ladder via rapid gripping elements. <IMAGE>

Description

WP I A0 111) DAUt 04#O1494 II 24PI03/94 PN T NUMER P(,t/193/00154 I iinlwiil (51 Itrationaile I'atentka,slfikation 5 E06C 7148 Off) tnternafionale ~rfetilitgnnnr WO) 93/25793 Al (43) Inlernatlnles Ner6fretlchungsdatuni: 21 1)eeemlwr 1991 Q Q2 12 (21) Iniernationales Aldcnzefcthen: (22) Internatlonalei %nmeldedatuin: NIT (1191 000~4 15 Juna 199.1050691) Veriifrntlcht Muft ,una:gunalcm IctI ht 'n hi Alt 11,1 1'uiuha '1 n'pruthit Prlorliitsdaten: 1888 921.0 16, Junt 1992 116 W92) (7l)72) Annielder und Erfindcr: HUSEN1IART, I'dwin [K1 CHI; Feldstrisse 39, CH-962 I Oberbell'enschwi (I) (74) AmWIa: A('K[RMANN. [rnst; Egghialde. ('11-9231 Egg.

1-lawil (11).

(81) Ilestimniungsstuaten: AU. 11R, CA. CZ. 1WU, JP. KR' P1,.

RO, RU, SK. UA. U'S. curoplischc Patent (AT, BE. ('11, D)E, DK, ES, FR. GB. OR, If-, IT. LU, NIC, NL, PT.1 S E).

(54)Tnite: LADD)ER, KIT AND) LEANING SUPPORT FOR LAD)DERS (54) Bezeichnung: LEITER, BAUSATZ SOWME ANSTELLSTCTzr. FOR LITER 't 32 24'' 24,1' (57) Abstract Ladders are equipped with a leaning support (20) during production or as an accessory, so that according to the use or the ladder they may be set up and used with a leaning element for flat walls for example even for glass surfaces or inner (21) and outer (22) corners of walls, as well as for large columns, in a safe and non-damaging manner. The invention allows peopie to work on a ladder with a safety against accidents which was hiterto impossible to achieve, and without damaging building components, vehicles, aircraft, ships and furniture.

(57) Zusammentassung Es wird vorgesehlagen, Leitern mit einer Anstellstfltze (20) bei der Herstellung oder als Zusatz auszuristen. dass, je nach Einsatz der Leiter diesc mit einem Anstellelement for flache Wande zumn Beispiel sogar f~r Glasflichen oder Wand- Innen- Wand-Aussen- Ecken auch sogar fdr gr~ssere S~iulen, sicher und beschdidigungsfrei gestellt und benutzt werden k~nnen. Die Erfindung erlaubt -mit elner bisher nicht m~glichen UnfalI-Siche~lieit auf' eincr Leiter zu arbeiten, ohne dass Schaden an Bauk~rpern, Fahrzeugen, Flugzeugen, Schiffen und Mobiliar entstehen.

Teiclal Field: TPhe invention wheles to laddlctes and pai'li( uhu lva. positioning suipport torit la(I(IPV.

~~Ldldersarv'( pr'obably amngst the oldest ids for wVorkivei. ad( miore and moure for loinlestic; and leisure use( as well, lor carrying out qifckly small tasks at heights which the average per1sonl cannot reach.

State of t1e Art: Ve!ry ian different kinds of ladder an. r odlucd. From for exampIlle very simpllle wooden ladders. iuiiiii ladlclis'. stepladdlers. to (IomlhicalPml laddePrs for example comfbinedl (lxteIiol and~ step ladders. Simiple leaii-oii ladders have thie advantage that positioning thnin at anl inclination against the wall results in putting the user at a certain distance [romn the wall, so that, depending onl the length of the ladder, ai(:cles of furniture, or' some.

body, or for example a strip of garden in a lower corner regionl between ground and wall are bridged and do not c:ause trouble. For lvani-on ladders there is anl olptilum angle of lean of about 70'. this (:orrespollding to safetVtechnology standards and regulations.

The aiccidlent risk rises with the height to which thle persoii using the ladder has to climb, particularly whenl the ladder, is used onl simooth ground sin..aces and walls, since in such cases there is often onlx' slight adhesion, because the contact surfaces on the ladder are very small and hard. The predominantly vertically acting forces emanating from the ladder user divide of course into a vertical force normal to the ground and a horizontal sliding force which, in the event of insufficient adhesion between ladder end and ground, on for example polished floors, can result in the ladder slipping away, which can be prevented only by a second person exerting counter-pressure on the foot end. When carrying out cleaning work on glass surfaces the risk of ladders slipping off is often obviated by using pairs of steps, or step ladders, which are independent of walls. But on the other hand a step ladder also has considerable other disadvantages, in fact, since it has only limited stability, and the working distances when carrying out work on walls are usually disadvantageous as well.

Slipping-away of a ladder at the foot end can be prevented by additional safety measures; on the other hand, ;ideol.ay.s li of t hr upp .r appl icat i I ,f d ladder on the wall is a further danger. Ho;:everr, the general experience is that going up ladders does not present great risks provided that regulations for use are observed: for example correct angle of lean, examination nf ground friction conditions, considering the nature of the wall :surface, satisfactory application of the upper ladder application ends against vertical surfaces and the lower foot end agains;t the ground.

Thus, dangers when using ladders result not only from weight loads but more particularly from the lateral actions of forces emanating from the activity of the person on the ladder. The stiles of a ladder are usually of slightly elastic construction, so that small unevennesses, or where floor and wall do not precisely form two surfaces at right i r 3 angles, are equalised-out elastically by ladder torsion.

But in many cases it is not possible to eliminate relatively large deviations in that way. In actual practice, therefore, desirable ideal conditions for the positioning of ladders are unfortunately not provided, so that the user often makes risky compromises. For example he or she goes up the ladder even when only the more or less hard, pointcontact application end of one stile is bearing against the wall. The other application end is then constrained by slight twisting of the ladder, though unsafely, to abut on the wall. Then especially if the user does not have a good natural technical sense, an unstable situation develops, since the action of the user's force co-operates with the internal/preload of the ladder, with an only limited pressureapplication adhesion. In addition, when such stresses occur the two foot ends also receive destabilising unfavourable force effects, resulting in dangerous accident situations.

Further scurc,'" nf danpg r 2 i in the fac th it ditions may be disadvantagcous to virtually inmpo: ;il e for positioning ladders in certain space circumstances such as external and/or internal corners formed by walls, and this is often neglected by ladder users.

A normal ladder also cannot, without additional ;ecuring arrangements, be leaned on pos;ts or columns of lisss than 40 cm diameter. Many accident-prevention authoriti',, and ladder manufacturers issue instruction literature indicating that such risky uses are forbidden, to avoid corresponding considerable risks of accident.

Besides known accident risks, ladder users come up against a further large problem area, that of damage to wall and ground or floor surfaces by scratching, rubbing and pressure marks, for example in the case of delicate' colour coatings, glass, stone, wood surfaces, etc.

4 Representation of the invention The invention had as its object more particularly to improve safety for ladder users, so that accidents connected therewith can be prevented as far as possible, also to considerably widen the safe range of possible uses for lean-on ladders and also to obviate damaging buildings, without complicating the work carried out standing on ladders or complicating the use of ladders. The invention had a further part-object to make it possible for existing ladders to be provided with subsequent equij ,ent, or refitted, in a simple and safe manner, and for use-specific various ladder application systems to be interchanged in seconds within the context of a modular system.

The solution according to the invention is charactexsed in that the two upper application ends have pairw?.searranged bearing contact surfaces which can be effedtive in or brought into two spatial directions. The inventor perceived that hitherto the /roblem of ladders was so to speak seen only in one pl ne, or in two, as far as the manufacturer was concerned In normal use a lean-on ladder i placed on the ground and positioned against the wall at n angle of 700. The ladder is dimensioned in accordane with given loads. The rest is up to the user.

For special uses it is nown to provide at the application ends for example s rew connections for example according to US PS No. 4 14 743. For normal lean-on ladders the manufacturers d not take into their considerations the third plane, transverse plane perpendicular to the wall, although t is precisely in this plane that the most problems ca be eliminated, such as: risks of accidents to users, da age to objects and articles.

T T /l To ensure safe support of the upper application ends a, aainst wall surfaces, simply bearing contact zones acting

UI

1/1- In a first aspect, the preselt invention provides a positioning support for a ladder having a pair of stiles comprising: a ladder head assembly for use with a plurality of different wall surface configurations, the assembly having a plane of synumetry and two supporting arms each having a distal end spacd from the plane, each distal end having an inner first surface positioned at about a 45" angle relative to the plane, a second surface positioned a aabout a 45 angle relative to the first inner surface and about perpendicular to the plane, and an outer third surface positioned at about a 45 angle relative to the second surface and about a 135" angle relative to the plane; and wall engaging means attached to each of thl, surfaces of the distal ends of the supporting arms.

The inventor perceived that hitherto the problem of ladders was so to speak seen only in one plane, or in two, as far as the manufacturer was concerned.

In normal use a lean-on ladder is placed on the ground and positioned against the wall at an angle of 70'. The ladder is dimensioned in accordance '.with given loads. The rest is up to the user.

For special uses it is known to provide at the application ends for example screw connections for example according to US PS No. 4 143 743.

For normal lean-on ladders the manuifacturers did not take into their considerations the third plane. a transverse plane perpendicular to the wall, although it is precisely in this plane that the most problems can be eliminated, such as: risks of accidents to users, damage to objects and articles.

To ensure safe support of the upper application ends against wall surfaces, simply bearing contact zones acting perpendicular against the wall are not adequate. It is more particularly preferred according to the invention to arrange the wall engaging means such that they contact the wall over a full surface and are constructed for example as interchangeable intensiveadhesion studs with circular bearing contact surfaces.

If additional wall engaging means are arranged to act in other spatial directions it is also possible to counteract the various forces acting from the work being performed. It is proposed to provide the two supporting arms in a paired/mirror-image configuration relative to the plane of symmetry for Al' o 4 rv~ multifunctional usability oin plane wall surfaces and internal and external corners. It has been found, surprisingly, that according to the invention not only is great additional safety achieved in normal cases of use against plan(, wall surfaces but for the first time, contrary to what is prescribed in the state of the art hitherto, the use of ladders onl internal and external corners is made possible, and even offers greater safety than when using ladders oil a straight wall. Many tests have shown a positioning safety even in many extreme situations such as could not be achieved hitherto by means of lean-on ladders of known type.

In a second aspect, the present invention provides a positioning support for a ladder comprising: a ladder head assemibly comprising two supporting arms, each supporting armn having a distal end with a plurality of surfaces having respective wall engaging means for engaging a flat wall, both walls onl either side of anl interior corner and both walls onl either side of an exterior corner; and ade.means for attaching the ladder head assembly to an uipper end of the in a further especially advantageous feature of the invention the *20 positioning prop or support is connectable via the articulations to the stiles, the articulations forming preferably an axis of icotation parallel to the rungs of the ladder. In the fitted state the positioning support is angled at about 1100 relatively to the stiles, and is so limited in both directions of rotation by abutments that it canl be lifted and lowered readily about the axis of rotation.

Tests have shown that by means of an articulated connection the normally occurring vertical spring moment of a lean-on ladder is reduced, and instead of an adhesion-reducing slipping of the bearing contact surfaces anl adhesionpromoting permanent compressive force is applied to the bearing contact surfaces. As a result, risks of accident or damage to wall surfaces are reduced or excluded. The wall engaging means may be constructed from individual, preferably interchangeable, rubber or plastics-type adhesion elements, for example as rubber studs. These wall engaging means canl be construct ed as round or miulti-face shaped elements, the bearing contact surfaces consisting of individual surface elements directed in various spatial directions.

According to a further feature it is proposed to construct the positioning support as an integral part of the upper end of the ladder.

Ini a third aspect, the present invention provides a positioning support for attaching to two parallel stiles of a ladder comprising: a ladder head assembly including two supporting arms, each supporting arm having a distal. end, each distal end having a plurality of surfaces at differing angles with wall engaging means attached to the plurality of surfaces of the supporting arms to engage a plurality of different wall surface configurations including at least both walls onl either side of anl internal corner, wherein the positioning support extends outward from a plan(, formned by the two parallel stiles of the ladder.

Ini a furtlier aspect, the present invention provides a kit for a ladder conmprising: a ladder head assembly including two supporting arms, each V, supporting arm having a distal end, each distal end having a plurality of surfaces at differing angles with wall engaging means attached to the plurality of surfaces of the supporting arms to engage a plurality of different wall surface configurations including at least both walls oin either side of anl internal corner, and to theat least one means for removably attachinig the ladder head assembly t theladder.

Often, new inventions bring actual progress in the sense that, with an insignificant outlay, considerable damage, accident risks, trouble etc.

could be avoided and/or rational and economic aspects are massively improved. But since an invention is connected fundamentally with products, all previous old products not having the new inventive quality should be replaced or discarded, But, on rational grounds, in actual practice this is only done to a small extent, which hinders real technical progress. In.

the case of ladders this problem could be solved in a surprisingly simple way with the idea according to the invention of a securing device for attaching a ladder head assembly to a ladder having a pair of stiles interconnected by rungs, the ladder head assembly inrluding two supporting arms, each supporting arm having a distal end an' i wall engaging means attached to the distal. ends of the supporting arms fom engaging a flat wall, both walls oin either side of anl interior corner and both walls on either side on an exterior corner the securing device comprising: an upper head portion for connecting to the supporting arms, the upper head portion including a transition section piece for engaging ends of the stiles; and a lower clamping portion for clamping the upper portion to the ladder.

The transition piece is fixable to the stiles, assemblable with forcelocking connections with le«-on ladders by means of a pin and hole pattern system even over ranges of many different rung spacings and rung dimensions. The transition ',ece can be of two-part construction; an 10 articulation head part securely attachable on or to the stile end, and a second clamping part adapted to be connected to said articulation head part and adapted to be clamped fast along the stiles preferably with respect to a rung.

to 90% of all existing ladders, or lean-on ladders, can be refitted in this way. Thus existing ladders retain their material value entirely, and can be 15 refitted with the new ladder head assembly according to the invention by means of a simple securing device.

r r r r V4 8 For the basic application function the kit has paired protective caps made preferably of rubber-type or synthetic plastic material type material, these being connectable at the articulations by means of rapid-action fastenings to the transition pieces and thus to the lean-on ladder.

As a further main element it comprises a positioning support for the multifunctionally extruded ladder use range, this being connectable via the articulations to the transition pieces and being constructed as a positioning element against internal wall corners and external wall corners and also as an application element for normal walls.

A securing element, preferably a rapid clamping element is provided for rapid assembly or disassembly and/or interchanging of various positioning supports or protective caps.

The interchangeable modular-type multifunctional positioning supports usually have preferably for both stiles pivot pins with surplus length for assembly with ladders of differing widths.

An especially advantageous feature of the invention in the form of a positioning support is characterised in that it has a plurality of elastic bearing contact surfaces which are arranged on two supporting arms pairwise in each case.

Preferably there are arranged on each supporting arm at least three elastic bearing contact surfaces whose directions of action form an angle, preferably of twice 450 in each case, constructed as a 3-function head.

It has been found that a lean-on ladder with a positioning support not only provides greater safety for the user but affords also the quite special advantage of greater/optimum spacing between ladder and wall in the uppermost region even with the greater safety achieved.

It is also proposed that the positioning support shall have a pivot pin or two pivot pins arranged on the opposite side 9 from the bearing contact surfaces, and preferably situated in a common plane with the bearing contact surfaces.

Advantageously, the bearing contact surfaces are constructed with variously orientated bearing contact surfaces, or as individual studs with an annular bearing contact surface.

In a further advantageous feature the positioning support, secured movably on a central pivot pin, has four pivotably secured supporting arms. Each of the four supporting arms can be brought by means of 900 locating arrangements integral with the pivot pin into three different positions and used fivefold-functionally through 450-angled bearing studs. The preferably soft individual bearing contact studs are made of rubber and/or soft synthetic plastic material, so that together with up to 8-fold positioning surfaces only optimum-reduced and careful pressure application forces result against highly vulnerable backgrounds such as for example glass. Especially preferably, the supporting arms are arranged to be individually pivotable for a multifunctional use capability on plane surfaces and/or at internal and external wall corners.

In the following the invention will now be described with the use of a plurality of examples of embodiment with further details.

Short description of the invention In the drawings: Fig. 1 shows a classic simple lean-on ladder; Fig. 2 is a side view of a refitted ladder according to the invention; Fig 2a is a plan view thereof positioned against a straight wall; Fig. 2b is a plan view when the ladder is positioned against an internal corner; Fig. 2c is a plan view when the ladder is positioned against an external corner; >1 10 Fig. 3 shows a flat positioning support; Fig. 3a shows a rubber stud with an annular bearing contact surface; Figs. 4, 4a, 4b, 4c show similarly to Figs. 2 a simple positioning support with fixed angled upper stile ends in the three basic forms of use; Fis. 5 and 5a show angled supporting arms which are connectable securely to the stiles; Figs. 6 and 6a correspond to Figs. 4, 4a, 4b; Figs. 7 and 7a show angled supporting arms which are connected to the stiles by means of a hinge; Figs. 8 and 8a show angled supporting arms which are connected to the transition pieces/stiles by means of a pivot pin; Figs. 9, 9a, 9b and 9c show the use of pairwisearranged one-piece supporting paws with variously orientated bearing contact surfaces in the three basic kinds of use; Figs. 10, 10a, 10b and 10c show similarly to Fig. 9 pairwise-arranged one-piece supporting paws but in circular-disc form; Figs. 11, lla, lib and 11c shou various elements oi a modular system, especially with a trancition piece; Figs. 12, 12a, 12b and 12c show various positions of protective caps; Figs. 13, 13a, 13b, 13c, 13d and 13e show a positioning support with four supporting arms for surface support.

9 1ligiiies 14. 14a, 141). 1-1c, sihow a simple ladder hevad devsigne'd (illb()(ling the inIventionl. tile stplyirting pawvs liig designe'd as a {CJltiilildi'iI of tile uppo ilds 01(5of the uprights, Figurie 1S shows a coliversioli system embiodyinug tile i nvenltioii for lcidl(iP Sill il side view ;onlsistinlg of traiisitioii pimv anid suppoiltiiig head( wvith s iI~portinmg paw~Xs designed as a thi'0PpurJpose hevad.

Figure 15a is a plan of Fignie Figure 16 shows a c;omp~lete ladder in jisL ile hevad wvith rapid grippinig ivlals for the transition pieces and rapid lockinlg inians (S-F-K) 11 for the suipporting head.

Figures i6a and 161) show, roughly schenmtahaly thle mounting of a trvans itioln piece and of thle supporting head.

Figure 16c shows a transit ion pic niluig rapid cilos ure mleanls.

*Figures 17 and 1.7a are a sidn view% and plan of a supporting head Ilimihlitmd directly oil a ladder.

Figure 18 shows a different designi of the shlled mlembier or attaching ~'lviUivitls.

Figure 18a, shows a supporting pawv as a partial plan of Figure 18.

Figure 1t) shows tile adjustiing of a. ladde(1r to a ledge-type b~uildinlg Figare I~N is a plani of Figure it).

~Figure 20 shows anl examplo of thle lIsv iithe laicdei' tccordling to igui'e it) oil a low building.

Figure 21 shows aill (ixteldale iiicdei'aditisted anid sup~ported i wall ledge.

Figure 22 showsV anl articulated head with ii hlinge pill.

~Figures 23 to 23c showv spherical supporting paws.

Figure 24 shows a Press ulould for tile supporting head: Figure 24a shows stampl~ing m11uld( for the supportinig lieiid iccordiiig to ligivr 2-1 priior to pressinlg, Figure 241) show~s thle finisiled suipp irtinmg hevad aiccordi nt to Figures 24 and 24a; Figutre is ai section 13-B3 fr'om Figur 24.

1 0i12- Ways of Ca'rrYing out the invent ion: ,Fig. I shows a convenitional simple lean1-0on ladder 1 which is supported on a floor 4 by means of a loot end 2 and is leaned against ia flat wall 5 by means of an uipper application endl 3. Thn lean-on ladder I has two Stiles 6 andI( 0' resp ct ively aind a pluirilitv of rungs 7. The stiles 63 and 6'of the lean1-on1 ladlder I are 54

S.

S S Sn.

*SSS

S S

S

A

-11 leaned at an inclination against the wall 5 at an angle of about 70° to the floor 4. Considered ideally a weight G corresponding to the weight of a user divides into a vertical force V and a horizontal force H on the floor, and an applic&tion force AW against the wall 5. The lean-on ladder 1 is first placed vertically on the floor 4 and then leaned against the wall 5 parallel to the wall 8 through a vertical plane 8' through an imaginary central line 9.

The two application ends 3 of the stiles 6 and 6' bring about the application force AW, these forces acting in substantially the same directions in a horizontal imaginary transverse plane 10. The corresponding angle (2 supplements the angle o being about 1100 relatively to the two stiles 6 and When being positioned against and taken away from the wall 5ithe lean-on ladder 1 basically carries out a movement according to arrow AB. It is assumed that at least during use the lean-on ladder 1, or the upper application end 3, carries out no lateral movement S within the transverse plane Fig. 2 should now be referred to, this showing an example of embodiment of the new invention, with the three most important varieties of use. Fig. 2 is a side view of a ladder 1 against a wall 5. The ladder 1 is leaned against the wall 5 via a positioning prop or support Fig. 2a is a plan view of Fig. 2 and shows the ladder 1 used at a flat vertical wall surface 5. Fig. 2b is also a plan view on to Fig. 2 but shows the use of the ladder 1 on an internal corner 21 formed by two corresponding wall surfaces 21' and 21". respectively situated at an angle of to one another. Fig. 2c is a further plan view on to Fig- 2, showing the ladder 1 used at an external corner 22 which is again formed by two corresponding wall surfaces 22' and 22" situated at an angle of 90° relatively.

I i 12 to one another.

The positioning support 20 is shown on a larger scale in Fig. 3 and comprises two supporting arms 23, 23' respectively which are formed in mirror-image relationship with respect to a plane of symmetry 24 and are connected securely by means of screws 25 to form one unit. Arranged at the two supporting arms 23, 23' respectively are a plurality of bearing contact surfaces 26, which are formed by individual rubber studs 27. The rubber stud 27 has a direction of action Rl parallel to .the vertical plane and brings about substantially a perpendicular positioning force AW and is intended for positioning against a flat wall 5. An example of a rubber stud 27 is shown in perspective in Fig. 3a and on a larger scale again. The positioning force AW is transmitted to the wall 5 via an annular bearing contact surface 26. Here, normal forces AN and friction forces AR resulting from the lateral force acLions AB, AB' respectively from the user are brought about, in accordance with the static friction between the material of the rubber stud 27 and the nature of the wall 5. Thus the stud 27 takes over very considerable lateral forces which emanate from the actions of force AB, AB' respectively. The rubber stud 27 is pressed preferably interchangeably into suitable holes 28 in the positioning support 20. The rubber stud 27' is directed to deviate at an angle of 450 from the direction of action of the positioning force AW, and is intended as a bearing contact surface 26 for an internal corner 21. Here the positioning force AW divides into a direction of action R2 and a direction of action R2' offset by 900, over the two supporting arms 23, 23' respectively. It will also be discerned from Fig. 3 that/depending on the action of force AB, or AB' respectively by the rules of statics a greater normal force is exerted either on the left-hand rubber stud 27' or on the right-hand rubber stud 27'. As a result,in -accordance with the increase in the normal force on the 13 rubber stud 27' the friction force increases, and thus the static friction is increased through the corresponding surface 26. Thus within a normal working action an increase in the lateral sliding force when using the ladder in a corner results in increasing the safety level of the ladder supporting forces. Analogously the force actions AB in the case of the rubber studs 27" result in an increase in the ladder supporting forces when using the ladder at an external corner. To increase safety/the studs 27" can be arranged double in each case.

Tie rubber studs 27"' come to be used when the ladder 1 is positioned against an upright or post. The effect in this case is identical to the action of the rubber studs 27".

In Fig. 3 an irregular line indicates a supporting paw 29 of the supporting arm 23'. At that side of the positioning supports 20 which is opposite from the rubber studs 27 there are arranged two pivot shafts 30, 30' respectively with a common axis of rotation 31, these being mounted rotatably by means of supporting bolts 32.

Figs. 4, 4a, 4b and 4c will now be referred to, these showing analogously to Figs. 2 to 2c the use of a ladder 1 on a flat wall 5 and on an internal corner 21 and external corner 22 respectively. Here the supporting paws 29 are identical to the construction shown in Fig. 3. But in Figs. 4, 4a, 4b, 4c the two supporting paws 29 constitute a prolongation of the stiles 6, 6' respectively, the app- -lication end 3 being angled-over at an angle of about 1100. The transition arc 40 can be part of the stile profile itself. This solution is especially suitable for rather short, one-piece, very economically priced ladders.

Figs. 5 and 5a show a variant of Figs. 4, with a positioning element 20'connected securely to the stiles for example by screwed connections.

2. 14 Figs. 6 and 6a correspond to Fig. 4.

Figs. 7 and 7a have a hinge 41 which establishes the connection of the positioning element 20" to the stiles 6, The hinge 41 can be put into an extended position (dashed line) when the ladder is not in use, so that only a small amount of space is required for storage. In the angled-over position (full-line position) a stop or abutment 42 secures in the working position.

Figs. 8 and 8a show the use of the positioning supports 20 in the case of a ladder '1 with an arrangement fastening by means of the pivot pins 30, 30' respectively. Fig.

8 shows that various ladder widths LB can be connected with the pivot pins 30, 30', since the corresponding dimensions Spi and Spa respectively of the pivot pins 30, 30' are designed in accordance with the largest and smallest ladder widths.

Figs. 9, 9a, 9b and 9c show a simplified form of the supporting paws 29a, the supporting paw 29a being formed here of a single body made of rubber or synthetic plastic material. The supporting paw 29a has an inside, front, and outside bearing contact surface 50, 51, 52 respectively, the inside bearing contact surface 50 forming an angle f of about 900 relatively to the outside bearing contact surface 52.

In Figs. 10, 10a, 10b and 10c a disc-shaped supporting paw 29b has been used.

Figs. 11 and 1la show the upper application end 3 of a ladder 1. On each of the two stiles 6, 6' a transition piece is mounted, at the head top and along the inside of the stiles 6, Each transition piece 60 consists of a joint head upper part 61 and a clamping part 62. The joint head upper part 61 is given a shape adapted to the head top, and can be secured by means of a cotter pin 63 in the stiles 6, 6' respectively. The clamping part is connected by means of dogs 64 to the joint head upper part 61, and is clamped by means of a clamping nut 65 to the joint head upper part 61 against a rung 7. The joint head upper part 61 has at the 15 end an articulation 66, which is constructed for securing e.g.

the pivot pins 30, 30', in accordance with Figs. 2 and 3. Each pivot pin 30, 30', (rotation axis 31) is secured against the transition piece 60 by means of a rapid-acting clamping element 67. Figs. llb, lc and lid have three different forms of transition section pieces 68, 68', 68" respectively so that the transition piece can also be adapted to various stile forms and/ or types. A rubber abutment 69 is also securely mounted on the transition piece 60. The rubber abutment 69 has a double function firstly, it constitutes a non-damaging bearing contact support on a flat wall 5, and secondly, the rubber abutment 69 also serves as an abutment for the positioning support 20 (Figs. 2, 2a, 2b, 2c).

Figs. 12, 12a, 12b and 12c show the use of protective caps which can be mounted on each stile 6, 6' for example, in place of the positioning supports 20, with the same kind of securing arrangement, by means of rapid-action clamping elements 67. The protective caps allow the application of the ladder against highly vulnerable surfaces so as to avoid damage and to protect the transition pieces 60 from fouling.

Figs. 13, 13a to 13e show a face support 80 which, in analogous manner to Figs. 2, 2a to 2c, can be secured by means of rotation axis 31 or pivot pin 30, 30' to the transition piece of a ladder 1. The face support 80 shows the double use of the supporting arms which here are offset vertically as a pair in each case. The upper support part 81 and lower support part 82 can be adjusted in each case by means of a spacing-pattern pivot 84/85 and secured onto the connecting rod 83. Fig. 13a shows the use of the face support on a flat wall 5, Fig. 13b on an internal corner, and Fig. 13c on an external corner. According to a further feature the two support parts 81 and 82 are adapted to move pivotally about a vertical pivot point 84, respectively outwardly and inwardly. Fig. 13d shows the support Jl

LI')

V, J/ parts 81 and 82 in the pivoted-in position on a straight wall 5. Fig. 13e shows the swung-out position wherein the supporting surface is almost doubled as compared to Fig. 13d. The solutions of Figs, 13d and 13e are suitable especially for leaning the ladder directly against glass or other highly vulnerable surfaces.

Further arrangements and embodiments can be seen from Figures 14 to 24c.

Figures 14, 14a, 14b, 14c show a simple ladder head design embodying the invention, the supporting paws being designed as a continuation of the upper ends of the uprights. The ladder head is a nondetachable part of the ladder. Any suitable means for connecting the ladder head to the ladder may be used for example riveted, welded or the paws can be constructed integrally, in one piece, with the stiles, It should be ensured that the upper part of the ladder and the connection is stiff enough to 15 withstand loads on the ladder. Figure 14 shows different applications corresponding the Figure 14a on a flat wall 5, Figure 14b on an internal corner :II: and Figure 14c on an external corner. All functions are identical as in Figures 2a-2c, The difference is the integration of the head instead of the system of rapid mounting.

Figure 15 is a side view showing a conversion system embodying the invention for ladders, consisting of transition piece ana supporting head with Ssupporting paws designed as a three-purpose head, Figure 15a is a plan of Figure 15. A head 100 is fixed on a transition piece 101, 101' whereby the supporting head 100 is clamped with a bolt 107 over a fixation rail 105, 105' in a slit 106 in the transition piece 101, 101'. The head is formed as a yoke with two paws 103, 104 connected with an angular inner piece 102, The fixation rail 105 is fastened to a surface 108, Figure 16 shows a complete ladder adjustable head with rapid gripping means for the transition pieces and rapid locking means (S-F-K) for the supporting head, Figures 1Ga and 16b show, roughly schematically the mounting of a transition piece and of the supporting head, Figure 16c shows a transition piece including rapid closure means. The fixation of the transition pieces is shown with more details marked with S-S and the fixation assembly 111 with all fixation elements 110-117. The fixation of the head is marked with S-F-K.

,'4 -10/1- Figures 17 and 17a are a side view and plan respectively of a supporting head which in this embodiment is mounted directly on a ladder with two pins 130.

Figure 18 shows a different design of the shaped member or attaching elements. Figure 18a shows a supporting paw as partial plan of Figure 18, The differences are in the shape of the paws. Several rounded rubber elements 204, 204' etc. are fixed on the outer parts of the supporting elements 100, to engage a flat wall, an internal corner or external corner, Figure 1 shows the adjusting of a ladder to a ledge-type building projection. Figure 19a is a plan of figure 19. The supporting head preferably has an additional rubber element 202 which supports directly on a horizontal surface 201 of the building projection 203. In addition the rubber element 107 leans on a vertical surface 200 resp. 200'.

Figure 20 shows an example of the use of the ladder according to 15 Figure 19 on a low building.

Figure 21 shows an extendable ladder adjusted and supported on a wall ledge.

Figure 22 shows an articulated head with a hinge pin 30, 30', as compared with Figure 4 which shows the supporting head as a integral part S 20 (40) of the ladder resp. stiles.

Figures 23-23c show spherical supporting paws. The lean-on surface is made by a ball or spherical shaped paws 208 which are fixed on both sides of the supporting head. The balls preferably are constructed from a resilient or grippy material to give good contact zones similar to the rubber stud 27 25 (see Fig. 3A) and provide strong static friction between the material of the ball and the nature of the wall, Figures 24-24c show an alternative construction of the supporting head. In this case the head is manufactured sheet material cut in the form shown in Fig. 24a, pressed to the shape shown in Fig. 24b and attached to the ladder stiles shown in Figs. 24 and 24c. To assist in attachment, mounting member 202 may be inserted or connected to the tops of the ladder stiles. A slit may be formed in the members 202 to receive the proximate end 201 of the supporting head, Fastening means 200 may optionally fix the proximate end 201 of the supporting head in the mounting member 202.

u j 1

Claims (16)

1. A positioning support for a ladder having a pair of stiles comprising: a ladder head assembly for use with a plurality of differeit wall surface configurations, the assembly having a plane of symmetry and two supporting arms each having a distal end spaced from the plane, each distal end having an inner first surface positioned at about a 450 angle relative to the plane, a second surface positioned at about a 450 angle relative to the first inner surface and about perpendicular to the plane, and an outer third surface positioned at about a 450 angle relative to the second surface and about a 135 angle relative to the plane; and wall engaging means attached to each of the surfaoes of the distal ends of the supporting arms.

2. The positioniing support of claim 1 further comprising means for attaching the ladder head assembly to an upper end of the ladder. '15 3. The positioning support of claim 2 wherein the attaching means fixedly attaches the ladder head assembl- to the upper end of the ladder.

4. The positioning support of claim 2 wherein the attaching means V. attaches the ladder head assembly to the upper end of the ladder in a rotatable manner.

5. The positioning support of claim 2 wherein the attaching means is formed as an integral part of the iupper end of the ladder.

6. The positionig support according to any one of the preceding claims wherein the two supporting arms are mirror images of one another along said plane.

7. The positioning support according to any one of the prec, ding :claims, wherein the wall engaging means arc rubber studs each having a circular cross-section and a recessed central frontal portion.

8. The positioning support according to any one of the preceding claims, wherein the two supporting arms further include means for engaging a post-type structure.

9. The positioning support of claim 8, wherein the post-type structure engaging means include a rubber stud on each arm disposed toward the central axis from the inner first surface. I! K, o 18 A positioning support for a ladder comprising: a ladder head assembly comprising two supporting arms, each supporting arm having a distal end with a plurality of surfaces having respective wall engaging means for engaging a flat wall, both walls on either side of an interior corner and both walls on either side of an exterior corner; and means for attaching the ladder head assembly to an upper end of the ladder.

11. The positioning support of claim 10, wherein the engaging means on each distal end comprises a single body having a middle first surface for flushly engaging the flat wall surface, an inner second surface positioning at about at 450 angle relative to the first surface for flushly engaging the outside 'corner, and an outer third surface positioned at about a 45° angle relative to the first surface for flushly engaging the inside corner.

12. The positioning support of claim 10, wherein said engaging means comprises a disk-shaped body.

13. A positioning support for attaching to two parallel stiles of a ladder comprising: a ladder head assembly including two supporting arms, each supporting arm having a distal end, each distal end having a plurality of surfaces at differing angles with wall engaging means attached to the plurality of surfacs of the supporting arms to engage a plurality of different wall surface configurations including at least both walls on either side of an internal corner, wherein the positioning support extends outward from a plane formed by the two parallel stiles of the ladder.

14. A kit for a ladder comprising: a ladder head assembly including two supporting arms, each supporting arm having a distal end, each distal end having a plurality of surfaces at differ.ng angles with wall engaging means attached to the plurality of surfaces of the supporting arms to engage a plurality of different wall surface configurations including at least both walls on either side of an internal corner, and at least one means for removably attaching the ladder head assembly 1 t, to tne ladder. 7t1 1 i i 19 The kit as in claim 14, wherein the attaching means includes a resilient abutment member oriented to extend outwardly from the ladder.

16. A securing device for attaching a ladder head assembly to a ladder having a pair of stiles interconnected by rungs, the ladder head assembly including two supporting arms, each supporting arm having a distal end and wall engaging means attached to the distal ends of the supporting arms for engaging a flat wall, both walls on either side of an interior corner and both walls on either side on an exterior corner the securing device comprising: an upper head portion for connecting to the supporting arms, the upper head portion including a transition section piece for engaging ends of the stiles; and a lower clamping portion for clamping the upper portion to the :o ladder.

17. The securing device as in claim 16 wherein the lower clamping portion clamps the upper portion to the rungs.

18. A positioning support for a ladder substantially as hereinbefore described with reference to Figures 1-13e of the accompanying drawings.

19. A kit for a ladder substantially as hereinbefore described with reference to Figures 1-13e of the accompanying drawings. 20 20. A securing device for attaching a ladder head assembly to a ladder substantially as hereinbefore described with reference to Figures 1-13e of the S: accompanying drawings. DATED this thirteenth day of May 1996 EDWIN BUSENHART Patent Attorneys for the Applicant: F.B, RICE CO.