EP1936108B1 - Stabilising strut for a ladder or scaffolding - Google Patents

Abstract

The arm (5) has an upper hinge (6) pivoted away from it laterally for lateral support of the ladder (1) where an end of arm prop (11,12) is connected with the ladder below the upper hinge and the other end of arm prop is connected with the arm pivoted both at ladder and sliding sleeves where the sliding sleeves is engaged through the arm and guided axially in a sliding manner. The material of the sliding sleeves (13,14) is made up of plastic and the material of the arm is made up of metal, particularly aluminum.

Description

The invention relates to a boom for a ladder or scaffolding according to claim 1.

For the lateral support of platform ladders, ladders, platform ladders, ladders and any scaffolds, it is known to pivot on each of the side of the ladder or scaffold a pivotable boom - in the form of a rod - to arrange.

The invention relates to according to all the above-mentioned ladders and scaffolding, in which it is possible to pivotally attach a lateral boom rod.

It is known to arrange the boom at the upper end of the ladder or the frame in a pivot joint and otherwise form the boom variable in length.

To move the boom to a working position (spread apart from the ladder or scaffold), the boom must be swung sideways and lengthened to allow a support point on the ground remote from the ladder or scaffolding.

If the boom is to be pivoted in and brought into a non-active rest position, then it must be pivoted to the ladder or the scaffold and its length shortened.

To support the boom on the ladder or the scaffold, it is also known to provide a further support or support at a distance from the pivot joint, which avoids that the issued boom unintentionally pivots away from the frame or the ladder.

For this support, it is known to use bands, with one band, for example, on one conductor part and the other band on the other Ladder part attaches and the two bands meet approximately in the middle of the boom and there are connected to this. In this way, a pivoting angle limit of the boom is achieved.

In another known embodiment, it is provided that instead of the bands hook-in wire hanger are used, each one part of the wire hanger is pivotally mounted on the boom and the opposite part of the wire hanger can be suspended or removed from the ladder.

Disadvantage of the bands used, however, is that they are limp. They protect the boom but only against a movement that is directed outwards, limit the span to the outside.

However, they do not protect against the fact that the boom moves slowly inwards when working with the ladder or scaffold and the ladder becomes unstable. In extreme cases, it may happen that the two side arms lift the ladder, whereby the ladder parts are then not all at the same time in contact with the footprint.

Disadvantage of the known, hinged struts, which limit both the span inwards and outwards, however, is that they must be hung separately, which requires an additional operation. In this type of attachment, there is a risk that the user does not make the hanging of the wire hanger, whereby the boom is not fixed, or there is a risk that the wire hanger unintentionally unhook, which affects the reliability.

Incidentally, there is a risk in this known solution that loose in the rest position herunterbaumelnden on the boom wire hangers lead to injury, unless they are still held in a special recording device. However, the suspension of the wire bracket in the rest position in the region of this recording device in turn requires another operation.

The DE 10104689 A1 discloses a ladder stabilizer, wherein a single telescoping boom is hingedly connected to the upper end of a goat ladder, and about the middle of the length of this boom is an axially displaceable sliding sleeve to which one end of a single telescopic boom strut is hinged, the other end thereof at the lower end of the spar the ladder is articulated.

The US 4641729 A discloses a step ladder, each with a telescopic boom 52 according to the preamble of claim 1, whose upper ends are hinged left and right at the upper ends of the spars of the Bockleiter, each boom 52 via a respective boom strut approximately in the lower quarter of the height of the Bockleiter is hinged on each spar of the Bockleiter. There are therefore two jib struts 52 per boom, which are connected at their ends, each with a sleeve 86, 88 on the boom 52. Although the two sleeves 86, 88 are arranged axially displaceable on the arm 52, but this is only done to adjust the sleeves 86, 88, then to the sleeves 86, 88 by axially above and below retaining rings 92 on the boom 52 in her to fix axial position. The sleeves 86, 88 are rotatably mounted on the boom 52, but they are not directly and directly connected to each other, but are only loosely on each other, supported by the locking rings 92. The folding and unfolding of the boom 52 on and from the ladder struts 34 takes place solely by the axial sliding of the boom struts 54, 58 in the slide bearing 81, 82, but not by axial displacement of the sleeves 86, 88 on the boom 52. The sleeves 86, 88 are during the folding or unfolding of the ladder through the locking rings 92nd set on the boom 52 in its axial position, but arranged rotatably there.

The invention is therefore the object of developing a boom for a ladder, a scaffold or the like so that it provides both a Schwenkwinkelbegrenzung the boom to the outside and inward, which works much more reliable and easier than the known solutions.

To solve the problem, the invention is characterized by the technical teaching of claim 1.

An essential feature of the invention is that the pivot limiting for the boom consists in particular two aligned superimposed sliding sleeves, which are penetrated by the boom and which are arranged displaceably on the boom, that in each case a boom strut with one end pivotally connected to the sliding sleeve and with its other end pivotally connected to a ladder part.

With the given technical teaching, there is now the significant advantage that a fixed boom strut assembly is provided for the fixation of the boom, as it was already known in the art in the form of aushängbaren wire hangers.

The main difference in the invention, however, is that these boom struts are now fixed and no longer removable, each attached to a ladder part and are pivotally mounted there.

If the boom in its rest position and this folded up on the ladder part or the frame, then the respective sliding sleeve is in the upper third of the boom, and the boom struts are arranged approximately parallel to the longitudinal axis of the ladder struts of the ladder part.

As soon as the ladder is opened, the boom is pivoted slightly outwards by means of a spring or by manual force. As a result, the sliding sleeves fall by gravity down and slide along the longitudinal axis down due to gravity on a dead center on the longitudinal axis of the boom.

This ensures that the boom can no longer move, so it remains in its swung-out position.

The swung-out position can only be reversed by moving with hand force on the boom struts or the sliding sleeves against the previous displacement movement of the sliding sleeves up to move these sliding sleeves back over the dead center on the boom and this while the boom towards its rest position against to move and lay the ladder.

It is therefore a self-locking arrangement of boom struts, which are articulated by means of two mutually movable sliding sleeves on the boom slidably.

This results in the significant advantage that now for the first time a firm connection between a boom and a ladder and a scaffold is given, which can not be unhooked, which is not lost and the boom both in the direction of its pivotal position to the outside and in his Pivoting position absolutely locked inwards.

Such a boom assembly can be attached to any ladder, scaffolding, podium, podium ladder and the like. The invention is therefore not limited to the arrangement of a particular ladder or a particular scaffolding.

It is also added that it is known to make the boom variable in length. Here, the invention provides several embodiments, and for such a change in length, it is important that the boom is pulled out to achieve its working position or extended in length to a support length, with the support length can adapt to the level of the ground.

At rest, the boom is shortened in length so as not to exceed the outer dimensions of the ladder or ladder parts.

For this Längenveränderbarkeit there are a variety of embodiments, which are claimed in connection with the invention articulation of the boom on the ladder.

Such variable length devices are z. As clamping devices that can change a telescopic boom in length or spring clamps or wedge clamps or Längenabsteckvorrichtungen, so that the boom rod consists of two telescoping telescoping tube parts, the length adjustment by inserting a stake in two oppositely aligned holes arranged in the one another reaching pipe parts is achieved.

In addition to the change in length due to the intermeshing of telescopic tubes, another embodiment provides for the boom to be designed to be foldable or otherwise variable in length.

The subject of the present invention results from the present set of claims.

In the following the invention will be explained in more detail with reference to drawings showing only one embodiment. Here are from the drawings and their description further features essential to the invention and advantages of the invention.

Figur 1:

ausschnittweise, perspektivische Darstellung einer Plattformleiter mit dem erfindungsgemäßen Ausleger in ausgeschwenktem Zustand

Figur 2:

eine vergrößerte Darstellung wie in Figur 1

Figur 3:

eine vergrößerte Darstellung der Anlenkung des Auslegers an dem oberen Leiternteil

Figur 4:

die Ruhestellung der Schiebehülsen der Auslegerstreben, wenn der Ausleger an die Leiter angeschwenkt ist

Show it:

FIG. 1:

partial, perspective view of a platform ladder with the boom according to the invention in swung out state

FIG. 2:

an enlarged view as in FIG. 1

FIG. 3:

an enlarged view of the articulation of the boom on the upper ladder part

FIG. 4:

the rest position of the sliding sleeves of the boom struts when the boom is pivoted to the ladder

In the embodiment shown, a stepladder 1 is shown, which consists of two ladder parts 3, 4, which are pivotally connected to each other at its upper portion by a bearing block 7.
In the region of the bearing block 7 in this case a pivot bearing 6 for the attachment of the upper end of a boom 5 is shown.

For graphic reasons is in the FIG. 1 only a single boom 5 shown, although in practice always on both sides of a ladder or scaffolding such a boom 5 is arranged.

Thus, the ladder is not only on the two pivotally hinged to each other ladder parts 3, 4, but also on the left and right of the ladder parts 3, 4 splayed out boom fifth

Each boom is variable in length. This has been explained in the general description above.

In order to bring the boom from a pivoted rest position into a swung-out working position, the invention provides that the boom 5 passes through two sliding sleeves 13, 14, which are thus arranged displaceably and with a corresponding sliding play on the boom 5.

Of course, to solve the invention is not necessary to use sliding sleeves as all-round, the boom 5 embracing sleeves. It can also be provided that the sliding sleeves embrace only about three quarters of the circumference of the boom or anyway more than half.

The sliding sleeves 13, 14 are preferably designed as pipe clamps, to which the invention is not limited. It is important that the profile of the sliding sleeves 13, 14 is adapted to the profile of the boom 5. Accordingly, the boom 5 could for example also consist of an oval profile or another profile, and the profile of the sliding sleeves 13, 14 would then adapted to this profile.

However, a prerequisite for this shaping is that the sliding sleeves are not only arranged longitudinally displaceable on the boom 5, but also rotatable. For this purpose, the profile shape of the sliding sleeves 13, 14 may be adapted to the profile of the boom 5 accordingly.

The FIG. 1 shows the swung working position of the boom brace. This is in conjunction with FIG. 2 recognizable that the two sliding sleeves 13, 14 in the direction of arrow 19 from a raised rest position to the working position FIG. 1 and 2 were moved automatically and gravitationally, according to FIG. 2 the two sliding sleeves 13, 14 have been moved so far in the direction of arrow 19 in the boom that they have overcome a dead center 20 and create below this dead center on a stop rivet 21.

Each sliding sleeve 13, 14 is in this case connected to a pivot bearing 17, 18, on which one end of a cantilever strut 11, 12 is pivotally hinged.

The other end of the respective cantilever strut 11, 12 is pivotally connected to a pivot hook 16, which is bent and with his bent end engages in a arranged on the inside of the respective conductor part 3, 4 hinge plate 15.

The bend of the swivel hook 16 and its pivotal mounting on both sides - on the boom strut 11, 12 and on the other hand on the hinge plate 15 - has the purpose that in the pivoted state of the boom 5, when this is approximately parallel to the longitudinal axis of the ladder parts 3, 4 directed , the two boom struts 11, 12 are pivoted in front of the ladder parts 3, 4 and therefore create on the outside of the ladder parts 3, 4 and can not get into the space between the ladder parts 3, 4.

This ensures that the two conductor parts 3, 4 can be completely closed, without the boom struts 11, 12 push into this space.

It is thus a positive guidance of the boom struts 11, 12 in their point of articulation on the ladder parts 3, 4.
The FIG. 3 shows as a preferred embodiment, an automatic or at least partially automatic swinging out of the boom under spring force.

For this purpose, it is provided that in the region of the pivot bearing 6 - which is hinged to the bearing block 7 of the conductor parts 3, 4 - a biasing spring 8 is arranged, with its one end on the pivot bearing 6 and with its other end 9 on the pivotable Part of the boom 5 supporting load.

It is an automatic swinging out of the boom 5. At rest, the two arms are fixed to the ladder parts 3, 4 with a tape or other locking device. Once this tape or the locking device has been released, the free spring end 9 of the biasing spring 8 acts on the pivotable part of the boom 5, which is thus pivoted in the direction of arrow 25 to the outside.

Due to this pivoting movement fall the two sliding sleeves 13, 14 - as with respect to the sliding sleeves 13 'and 14' in FIG. 1 is indicated by dashed lines and their upper raised position due to gravity in the direction of arrow 19 down, like this in FIG. 1 shown in solid lines.

Of course, the invention also relates to a solution in which the biasing spring 8 can be omitted. If the biasing spring 8 is omitted, the necessary pivotal movement in the direction of the arrow 25 must be carried out completely by hand.

It is also added that the boom 5 is pivotally supported in the pivot axis 10 on the pivot bearing 6.

When moving the sliding sleeves 13, 14 in the direction of arrow 19, these rotate at the same time on the boom 5, which in FIG. 4 is shown.

The sliding sleeve 13 shifts from its rest position 13 'in the direction of arrow 22 (here, for example clockwise), while the sliding sleeve from its rest position 14' in the position 14 in the direction of arrow 23 (here counterclockwise, for example) twisted, so that the Turning directions of the two sliding sleeves 13, 14 are opposite to each other. The connection of the sliding sleeves 13, 14 via a snap-locking connection.

The FIG. 4 shows at the same time that in the rest position, the respective cantilever strut 11 ', 12' is aligned exactly parallel to the longitudinal axis of the conductor parts 3, 4.

The previously described overcoming the dead center 20 is according to FIG. 1 defined by the angle 24 between the longitudinal axis of the boom strut 11, 12 and the longitudinal axis of the boom 5 is less than 90 degrees to achieve the desired self-locking.

In this position, it is no longer possible to bring out by attacking the boom or the ladder from its swung working position.

Even moving the ladder sideways, with a boom lifting off the footprint, will not cause it to leave its working position. He always stays in the swung-out position. Therefore, this does not lead to an undesirable migration of the erection point of the boom in the direction of the ladder, whereby the ladder is lifted.

With the invention, there is the advantage that the boom struts are now virtually inextricably linked to the ladder parts 3, 4 and there is no need for separate operation of the boom struts 11, 12. Likewise, an automatic pivoting of the boom takes place from the retracted rest position into the working position, which is supported by spring force.

This leads to a very comfortable operation of a ladder or a scaffold with jibs attached laterally thereto. Therefore, there can be no operating errors in the operation of the boom.

drawing Legend

1

stepladder

2

platform

3

ladder section

4

ladder section

5

boom

6

pivot bearing

7

Bearing block (for ladder parts)

8th

biasing spring

9

The End

10

swivel axis

11

boom strut

12

boom strut

13

sliding sleeve

14

sliding sleeve

15

hinge plate

16

swivel hook

17

pivot bearing

18

pivot bearing

19

arrow

20

dead

21

Anschlagniet

22

arrow

23

arrow

24

Angle <90 °

25

arrow

Claims (10)

1. Stabilising arm (5) for a ladder (1) or a work scaffold or the like, which can be articulated thereon by an upper pivot joint (6, 10) and can be pivoted away for the lateral support of the ladder (1) to the side thereof, wherein the stabilising arm can be connected below the pivot joint (6, 10) by the respective ends (3) of pivoting arm struts (11, 12) to the ladder (1), the other ends of which are in each case connected to the stabilising arm (5), the stabilising arm struts (11, 12) being pivotably articulated both to the ladder (1) and also pivotably articulated to a sliding sleeve (13, 14), and the sliding sleeve (13, 14) having the stabilising arm (5) engaging through it and being axially displaceably guided thereon, and at least two sliding sleeves (13, 14), which are arranged aligned one above the other on the stabilising arm (5) and are axially displaceable thereon, being provided, said sliding sleeves being connected, in each case, in an articulated manner to one of these stabilising arm struts (11, 12) and the two sliding sleeves (13, 14) being connected to one another so as to be rotatable with respect to one another, characterised in that the two sliding sleeves (13, 14) are connected by a snap-on/latching connection.
2. Stabilising arm (5) according to claim 1, characterised in that in the operating state with stabilising arms (5) folded out laterally from the ladder (1), the sliding sleeves (13, 14) are located below a dead centre (20) self-locking the axial displaceability of the sliding sleeves (13, 14), the dead centre (20) being defined in that the angle (24) between the longitudinal axis of the stabilising arm struts (11, 12) and the longitudinal axis of the stabilising arm (5) is less than 90 degrees in order to achieve the self-locking.
3. Stabilising arm (5) according to claim 2, characterised in that the two sliding sleeves (13, 14) rest below the dead centre on a stop rivet (21) of the stabilising arm (5) when the stabilising arm (5) is in the pivoted-out working position.
4. Stabilising arm (5) according to any one of claims 1 to 3, characterised in that the snap-on/latching connection of the at least two sliding sleeves (13, 14) is a peripheral tongue and groove connection on the casing side.
5. Stabilising arm (5) according to any one of claims 1 to 4, characterised in that the stabilising arm struts (11, 12) can be rigidly and non-removably fastened to the ladder (1).
6. Stabilising arm (5) according to any one of claims 1 to 5, characterised in that the stabilising arm (5) is of adjustable length.
7. Stabilising arm (5) according to any one of claims 1 to 6, characterised in that the ability of the stabilising arm (5) to pivot away from the ladder (1) is effected at least at the beginning by means of a prestressed spring (8).
8. Stabilising arm (5) according to any one of claims 1 to 7, characterised in that the pivot joint (6, 10) has a pivot bearing (6), which can be fastened to a bearing block (7), which can form the articulated connection between two ladder parts (3, 4), which can be adjusted relative to one another, of the ladder (1) configured as a step ladder.
9. Stabilising arm (5) according to any one of claims 1 to 8, characterised in that the articulating ability of the stabilising arm struts (11, 12) is effected at a side rail of the ladder (1).
10. Stabilising arm (5) according to any one of claims 1 to 9, characterised in that the material of the sliding sleeves (13, 14) is made of plastics material and the material of the stabilising arm (5) is made of metal, in particular aluminium.

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