EP3252261B1 - Foldable cross brace for pitching ladders and multi-piece ladders - Google Patents

Description

The invention relates to a foldable traverse according to the preamble of claim 1.

By revising the European ladder standard DIN EN 131-1, ladders have to be adapted to newly defined requirements in order to ensure stability during use.

An important change to the standard relates to increasing the minimum landing width for ladders with a total length greater than 3 m. Previously, this minimum stand width for ladders was already given by the distance between the two ladder stiles. Therefore, no additional stabilization device, so no broadening of the footprint was necessary. The implementation of the standard adaptation to one-piece Anlegel ladders is not a major problem. There, as before, simple trusses can be used because they are very inexpensive and safe.

However, the amendment of the standard poses a challenge for three-part general-purpose ladders.

A general purpose ladder consists of a top, middle and bottom part. The protruding at an angle from the middle part lower part has at the Leiterfuß a traverse stabilizing device. This was according to the requirements of the previous standard due to the total length of the conductor, which results in the extended state, prescribed. The middle part and the upper part arranged displaceably on it has S-shaped hooks on the bars. These are hung at the desired height in the rung of the underlying ladder section to fix the extended ladder.

In the case of a three-part ladder, guide fittings on the lower and middle sections serve to guide the respective other ladder section, hold the ladder sections together and give them the desired stability.

The ladder top of the general purpose ladder can be removed to use as a one-piece ladder. For this, the S-shaped hook is unhooked and the upper part of the ladder pulled out over the fitting of the middle part.

The adaptation of the ladder standard in this case prescribes, if the detachable ladder section exceeds a length of three meters, to equip it with a stabilizing device. However, the stabilizer must not interfere with the functions of the ladder and cause any risks of use.

Such a risk of use exists, for example, if a stabilizer is already attached to the ladder beginning of the detachable ladder section and obstructs the user's ascent to the utility ladder.

Alternatively, the stabilizer may be attached to the top of the detachable ladder section, since the user is not impaired in the ascent. However, the well-known, fixed at the end of the ladder trusses protrude beyond the ladder geometry.

The company Haca Leitern GmbH & Co. offers a universal folding traverse as an accessory for ladders ( DE 10 2014 117 975 A ). This Traverse consists of two crossbar legs which protrude at one in front of the plane formed by the plane of the spars.

In this superior receiving plate, the truss legs are rotatably mounted at the lower end of the spars in the range of simple pivot axes. The crossbeams can be rotated by 90 ° until they snap into place and stand in the folded position vertically in the area between the crossbeams and indeed in the plane in front of the spars next to each other. The latching takes place by means of a spring on stop rivets in the spar and a milled groove on the mounting profile. In this case, there is the disadvantage that, due to the mounting plate projecting forward over the plane of the spars, the packing size, that is to say the entire dimension of an assembled conductor, is very large. Although the truss legs are folded down to the middle of the ladder stiles, but the truss legs are mounted on the front side of the spars, making it no longer possible, a ladder with attached crossbar in another ladder part, as is common in multi-part ladders to record. The crossbar would collide with the guide fittings of the other ladder part. The well-known universal folding traverse can thus not be pivoted into the space bounded by the clear width of the spars receiving space, but protrudes in all pivot positions beyond.

This disadvantage is also liable to GB 1909/9014 A on, in which the two truss legs are held in a pivoting pivot on the respective Holminnenseiten and are arranged in front of the plane of the spars. The patent DE 10 2007 061 357 B3 shows a crossmember whose crossbar legs are pivotally mounted on receiving profiles at the end of the bar. The truss legs are each pivotally mounted with their upper ends in a horizontally displaceable strut. A disadvantage of this device is that the truss legs always protrude laterally beyond the spars from the ladder and thus take up much lateral space. Accordingly, they can not be folded into the plane spanned by the clear width of the spars.

The document US 2013/0292525 A1 discloses a folding cross member according to the preamble of claim 1. In all known folding trusses there is the disadvantage that they always protrude in the folded state on the outer geometry of the actual ladder and thus are problematic to transport. An insert in the ladder part of a multi-part extension ladder is therefore not possible.

A simple removal, for example from a holder of a fire truck is thus no longer guaranteed. The traverse must be mounted by the user and disassembled for transport again, which involves a high amount of time for assembly and disassembly.

The invention is therefore an object of the invention to provide a folding Traverse available, which can be used both in simple and multi-part ladders, without that they claimed on the outer geometry of the ladder additional space, especially not in the folded state across the width and clear width of the spars stands out.

The invention solves this problem by the feature of claim 1.

The foldable cross member according to the invention has two elongated crossbar legs, which are each slidably received in the longitudinal direction in a pivotable receiving profile at the end of a spar of the ladder and connected to each other via a common pivot point.

The common pivot point is located in each position of the truss legs midway between the spars and has no connection to the parts of the ladder.
While at the DE 10 2007 061 357 B1 two spaced apart, ladder-fixed, central pivot joints were provided for the central pivot bearing of Traversenbeine, the invention dispenses with two central conductor-fixed pivot bearing, but uses a single free pivot bearing without connection to parts of the ladder for central pivotal mounting of the truss legs.

The invention therefore consists in that the crossbar legs are connected together in their end connection area via a common, ladder-free pivot point.

In this way, the hinged traverse can be pivoted into a position in the interior of the ladder, and in the extension or Ausklappfall the two pivotally arranged traverse legs are swung in a straight line and locked there. This has the advantage that the truss legs are arranged in the pivoted state in the interior between the spars and protrude neither in depth nor in width on the spars out.

The folding truss legs are fastened to the ladder rails by means of receiving profiles. These receiving profiles consist of two joint parts, which are preferably made of plastic, for example PA6 GF30. However, the invention is not limited to this, it is also possible to use aluminum diecasting or other materials.

The upper joint part is constructed as a plug-in part to positively transfer the emerging forces on the ladder rail, in which it is plugged. In a further embodiment, the upper joint part can also be material integrally formed on the conductor, or be connected by a screw connection to the ladder struts.

The lower hinge part has a receiving opening for receiving the truss leg. For the lower joint part PA6 GF30 is also preferably chosen as the material, since the aluminum truss profile is guided in the receiving opening and by the combination of material combination aluminum / plastic good sliding properties arise.

The lower hinge part has a recess for the spar, which is located off-center to the ladder to ensure the folding mechanism. Otherwise, the traverse would be pending on the rung when folding. The lower hinge part must be replaced by the folding mechanism of the crossbar profiles fold in so far as to ensure removal of the ladder section.

The upper and lower joint part is connected to one another via a screw, wherein the screw axis forms the pivot axis of the two joint parts, which can be pivoted against each other on the said axis.

In the assembled joint both the screw head, and the lock nut is sunk in order to ensure a decrease in the conductor part and not to collide with the removal of the conductor part with the guide fittings.

The composite joint is inserted into the spar and screwed with a screw or riveted with a rivet. Thus, a simple installation is guaranteed.

The crossbeam is also designed as a male part and designed so that it can be used for both sides of the ladder. For the truss joint, cast aluminum is the preferred material.

On the projecting into the space between the two spars end of the crossbar a stop is attached to the upper edge, which rests on a contact area of the second crossbar joint and thus determines the final position of the crossbar legs when unfolding.

The second transverse joint also has such a stop, which rests on the contact area of the first traverse. Thus, the truss legs can only be folded up to this position and are in this position horizontal.

The truss joint is received in a hollow truss profile, which is pushed into the receiving profiles on the spars. Preferably, an aluminum profile is used. However, the invention is not limited thereto. In an alternative embodiment, the truss leg is integrally attached to the ladder.

On the truss profile, a truss foot, hereafter called foot, is attached to the opposite side of the truss joint. For the truss foot, the material PVC Sh.A70-90 is preferred, in order to ensure a secure position of the ladder and to prevent slippage of the ladder. It is a mirror image designed to use a one-piece laying ladder on both sides.

For a simpler design of the components is assumed by a force FGes, which acts starting from the conductor perpendicular to the traverse invention.

For the calculation of the force on the stop of the traverse joint is assumed by a force FGes / 2, which acts on a Traversenbein. Since it is assumed that the force FGes acts centrally on a rung of the ladder, this force is distributed on both ladder bars and thus on the truss legs.

As a counter force, the Aufstandsskraft the truss foot and the force on the attack. The bearing force FL acts on the axis which connects the two traverse joints. If the traverse is considered as an overall system and all tolerances of the components are respected, act on the axis only small forces, as they are previously intercepted by the two stops.

Thus, the entire force FGes / 2 distributed to the truss foot and the stop.

The subject of the present invention results not only from the subject matter of the individual claims, but also from the combination of the individual claims with each other.

All information and features disclosed in the documents, including the summary, in particular the illustrated in the drawings, are claimed as essential to the invention, as far as they are individually or in combination compared to the prior art and do not go beyond the scope of the following claims.

As far as individual items are referred to as "essential to the invention" or "important", this does not mean that these items necessarily have to form the subject of an independent claim. This is determined solely by the current version of the independent claim.

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:

perspektivische Ansicht Traverse (ausgeklappt)

Figur 2:

perspektivische Ansicht Traverse (eingeklappt)

Figur 3:

perspektivische Ansicht Leiter in Anlegestellung

Figur 4:

perspektivische Ansicht des ausgebauten Oberteils

Figur: 5

Draufsicht auf Figur 3

Figur 6:

perspektivische Ansicht Leiter als Stehleiter

Figur 7:

Krafteinwirkung auf Traverse

Figur 8:

Krafteinwirkung auf Traversenbein

Figur 9:

grafische Darstellung der Kräfte

Figur 10:

perspektivische Ansicht Traversengelenk

Figur 11:

perspektivische Ansicht oberes Gelenkteil

Figur 12:

perspektivische Ansicht unteres Gelenkteil

Figur 13:

perspektivische Ansicht Traversenprofil

Figur 14:

perspektivische Ansicht Fuß

Show it:

FIG. 1:

perspective view Traverse (unfolded)

FIG. 2:

perspective view Traverse (folded in)

FIG. 3:

perspective view ladder in landing position

FIG. 4:

perspective view of the removed shell

Figure: 5

Top view FIG. 3

FIG. 6:

perspective view ladder as step ladder

FIG. 7:

Force on Traverse

FIG. 8:

Force on the truss leg

FIG. 9:

graphical representation of the forces

FIG. 10:

perspective view of crossbar joint

FIG. 11:

Perspective view upper joint part

FIG. 12:

perspective view lower joint part

FIG. 13:

perspective view truss profile

FIG. 14:

perspective view of foot

FIG. 1 shows a ladder 1, which consists of two bars 2 and arranged therebetween rungs 3. The spars have a depth 51. The ladder has at its bottom end 13 on two receiving profiles 7 and 8, which are attached to the spars 2.

The receiving profiles 7 and 8 consist of an upper joint part 14, a pivotally mounted thereto lower joint part 15, which has a receiving opening 31 open on both sides. In the receiving openings 31 of the receiving profiles 7 and 8, a cross-member profile 60, 61 and an inserted therein Traverse articulated 5 and 6 is added in each case.

The truss joints 65, 66, which consist of transverse joints 5, 6 and transverse profile 60, 61, are thus connected to the ladder. The two Traverse legs 65, 66 form the traverse 4, which rests with the lateral feet 39 on the ground and the conductor 1 stabilized.

The two truss joints 5 and 6 are connected via a pivot point 9, which is located centrally between the bars 2, pivotally connected to each other. The cross joints 5 and 6 are located in FIG. 1 in their unfolded position and have between them an opening angle 16 of about 180 °.

The crossbeam 5 has at its end projecting into the intermediate region of the spars 2 a material integral stop 33, which rests on the abutment portion 47 of the other crossbar joint 6. The abutment region 47 of the traverse joint 6 is located between the central pivot point 9 and the left-side spar.

Likewise, the cross-beam joint 6 at its projecting into the intermediate region of the spars 2 end a stop 33, which lies on the abutment portion 47 of the other truss joint 5.

The contact region 47 of the transverse joint 5 is located between the central pivot point 9 and the right-hand spar.

Thus, the traverse joints between the investment areas are parallel and the force acting on the ladder weight is transmitted from the respective stop 33 on the contact area 47.

FIG. 2 shows the hinged cross-piece according to the invention in the folded state. The truss legs 5 and 6 protrude into the interior of the ladder. In this state, all components are included within the conductor 1, ie the depth of the conductor 1 with the cross member 4 is determined by the depth 51 of the spars, since no component protrudes beyond the dimension of the spars 2.

The crossbar profiles 60, 61 are pushed up to their plugged feet 39 through the receiving opening 31 of the receiving profiles 7, 8 and project maximally into the interior of the ladder 1. In this position, there is an opening angle 17 of less than 45 ° between the crossbeams 5, 6 , The pivot point 9 of the transverse joints 5, 6 is located above the first rung 3. The stops 33 are no longer in this position in engagement with the abutment areas 47 of the other traverse joint.

FIG. 3 shows a ladder designed as an extendable ladder 1, which consists of a lower part 26, a middle part 27 and an upper part 28. The conductor 1 is connected to the bottom end 38 of the lower part 26 on the ground. The middle part 27 is held by guide fittings 24 at the upper end 36 of the lower part 26. The middle part 27 in turn has a guide fitting 24 with which the upper part 28 is held. At the upper end 37 of the conductor part 28, the cross member 4 according to the invention is attached. In the example shown here, the cross member 4 is inserted into the spars 2 of the upper part 28.

FIG. 4 shows the top 28 of the ladder in the disassembled state. In this case, the upper end 37 is rotated in the direction of the ground and is on the feet 39 of the cross member 4 on this. The Traverse 4 can now be unfolded to give the dismantled and thus single Oberteil 28 the necessary stability.

FIG. 5 shows the ladder FIG. 3 in plan view. Here, the cross member 4 according to the invention is attached to the upper part 28. The upper part 28 forms in plan view the outermost conductor element of the three-part conductor 1, while the middle part 27 is arranged between the upper part 28 and the lower part 26.

The lower part 26 holds on the guide fittings 24, the middle part 27 and the middle part 27 via the guide fittings 34, the upper part. Thus, the Parts 26-28 are moved against each other and fixed in the desired position by not shown S-shaped hooks.

The lower part 26 as the widest conductor part defined with its bars 2 together with the guide fittings 24 and 34, the outer geometry 32 of the ladder 1. Within the outer geometry are the three ladder parts 26, 27, 28 with the guide fittings 24, 34 and the folded cross member 4 with its middle pivot point 9.

Outside the ladder geometry a rigid cross member 25 is attached to the bottom end 38 of the lower part 26, which rests on the feet 40 on the ground.

FIG. 6 shows a stepladder 1 consisting of a conductor part 10a and an angle thereof pending ladder part 10b. The conductor parts 10a and 10b are connected to their upper ends. A webbing 42 prevents further unfolding of the ladder parts. On ladder part 10a, a further ladder part 11 is slidably received on the guide fittings 24, which can be fixed via not shown S-shaped hooks on the ladder part 10a.

The straight ladder part 11 has at its upper end 41 a traverse 4 according to the invention, which is in the folded state. The Traverse 4 has the truss legs 65 and 66 and the feet 39th

The ladder portion 11 can be detached from the ladder portion 10a to use as a stand-alone ladder. Such a ladder is in FIG. 4 shown and described.

FIG. 7 shows the effect of the individual forces on the traverse 4th side of the ladder, the total force 18, which acts on the spars 2 in the forces Fges / 2 and Fges / 2 divides, on the traverse 4. This results in the feet 39 of the traverse 4 respectively the forces 22 and 23 which counteract the total force 18 act. The cross-joints are pivotally connected to each other via the screw 64.

The attached at the end of the spars receiving profiles 7, 8 have a screw 63, with which the upper hinge part 14 and the lower hinge part 15 of the respective receiving profile connects and forms the pivot axis between these parts. Since the respective truss leg 65, 66 is received in the lower joint part 15, the screw 63 also forms the pivot axis for a truss leg. The bearing force 19 acts on the screw 63.

FIG. 8 shows the effect of half the weight of 54 on a truss joint 5. The truss steering 5 has a hole 48 into which a bolt or the like is received to form the central pivot point 9 as a rotation axis. The truss joint 5 is held by the receiving profile 7.

The force acting on the ladder weight 18, which bisects depending on the beam in the forces 54. This force 54 counteract the force 22 as a supporting force of the foot 39 and the force 43 as a supporting force of the stop 33. The force on the underside of the force 43 on the stop 33 is transmitted from the other transverse joint 6, not shown.

FIG. 9 shows a graphic representation of the traverse joint FIG. 7 acting forces.

The force 22 as a support force on the crossbeam joint 5 acts in the contact point 52 of the foot 39 and is removed with the length 20 from the point of application of the force 54. The force 43 as a supporting force on the support point 53 of the stopper 33 is removed with the length 21 of the applied force 54. Between the support point 52 of the foot 39 and the support point 53 of the stopper 33 is the Length 44. The effect of the force 54 on the support points 52, 53 thus results from the ratio of the lengths 20 and 21.

FIG. 10 shows a truss joint 5 which has a receptacle 49 for insertion into the truss profile 60, 61 has. In addition to the receptacle 49, the abutment region 47 is arranged, on which the abutment 33 of the other, not shown, transverse joint 6 comes to rest. Thus, the crossbeam 5 has a stop 33 which rests on the abutment region of the other, not shown, transverse joint 6.

FIG. 11 shows the upper hinge part 14, which may preferably be made of plastic as well as of die-cast aluminum, steel or other material. The upper hinge part is inserted in the direction of arrow 29 in the hollow ladder spar 2 to the stop 55. The joint part 14 has integrally formed on the stop guides 57, each with a bore 56. The bores 56 define an axis 30 in which a bolt, not shown, can be received, which rotatably supports the lower joint part 15 between the guides.

In the insertion region of the upper joint part 14, that is, up to the stop 55, the joint part struts 45, which intersect in the middle. In this crossing point is a bore 46 which serves to fix the joint part 14 in a spar. Such a fixation is for example possible by a plugged rod or a screw.

FIG. 12 shows the lower hinge part 15. The lower hinge part 15 also has a guide 58 with a bore 59 for receiving the bolt, not shown. Through the bore 59 also extends the axis 30, which forms the pivot axis of the composite joint in the assembled state of the two joint parts 14, 15. Thus, the lower joint part 14 is added below a spar and can be pivoted about the horizontal axis 30.

The lower hinge part 15 has a receiving opening 31 for receiving a traverse joint.

FIG. 13 shows the truss profile 60, 61 in the direction of arrow 62 of the foot 39 is plugged. The foot 39 opposite the crossbar joint 5, 6 is inserted and fixed by screws.

FIG. 14 shows the foot 39 which in the direction of arrow 62 on the truss profile after FIG. 13 is plugged ..

drawing Legend

1

ladder

2

Holm

3

rung

4

traverse

5

Travers joint

6

Travers joint

7

Up profile

8th

Up profile

9

Pivot point (of 4)

10

Ladder part 10a, 10b

11

Ladder part (from 1)

12

upper end (from 1)

13

lower end (from 1)

14

Upper joint part

15

lower joint part

16

opening angle

17

dwell

18

total power

19

bearing force

20

Route I1

21

Path I2

22

force

23

force

24

guide fitting

25

solid crossbeam

26

lower part

27

midsection

28

top

29

arrow

30

axis

31

receiving opening

32

external geometry

33

attack

34

guide fitting

35

upper end (of 26)

36

upper end (from 27)

37

upper end (from 28)

38

Bottom end (of 26)

39

Foot (from 4)

40

Foot (from 25)

41

upper end (from 11)

42

safety belt

43

Force on 33

44

Route I3

45

strut

46

well

47

plant area

48

hole

49

Recording (for 40)

50 51

Depth (from 2)

52

Point of support (from 39)

53

Point of support (from 33)

54

Half of the total force

55

attack

56

drilling

57

guide

58

guide

59

drilling

60

Travers profile

61

Travers profile

62

arrow

63

screw

64

screw

65

Travers leg

66

Traverses leg

Claims (9)

1. Foldable traverse (4) for stabilising a ladder (1), having two elongated traverse legs (65, 66) which are received to be longitudinally displaceable respectively in a pivotable receiving profile (7, 8) on the end of a side rail (2) of the ladder (1) and in the gap between the side rails (2, 2) have pivot bearings in their end-side connecting region, wherein the traverse legs (65, 66) are connected to one another in their end-side connecting region via a common, ladder-free pivot point (9), wherein each of the traverse legs (65, 66) is formed in two parts and consists of respectively a traverse profile (60, 61) and a traverse hinge (5, 6) received therein, wherein the traverse hinges (5, 6) together form the centre of gravity, characterised in that a stop (33), which in the opened-out state of the traverse (4) is placed on a support region (47) of the respective other traverse hinge (5, 6) and thus limits the extended position of the opened-out traverse legs (5, 6), is attached to the upper edge of each traverse hinge (5, 6).
2. Traverse (4) according to claim 1, characterised in that the two traverse hinges (5, 6) are connected to one another to be pivotable via the pivot point (9).
3. Traverse (4) according to one of claims 1 to 2, characterised in that the side rail-side receiving profile (7, 8) is formed in two parts and consists of an upper and a lower hinge part (14, 15) which are connected to one another to be pivotable via a screw (63).
4. Traverse (4) according to one of claims 1 to 3, characterised in that the lower hinge part (15) of the side rail-side receiving profile (7, 8) has a receiving opening (31) for receiving the traverse leg (65, 66) mounted there to be longitudinally displaceable.
5. Traverse (4) according to one of claims 1 to 4, characterised in that the upper hinge part (14) is insertable into the side rail (2) of the ladder (1).
6. Traverse (4) according to one of claims 1 to 5, characterised in that the traverse legs (65, 66) in the pivoted-in state, may be pivoted-in in the interior between the side rails (2, 2) of the ladder.
7. Traverse (4) according to one of claims 1 to 6, characterised in that the traverse legs (65, 66) in the pivoted-out state, form a horizontal extended position and in that the traverse hinges in this position have an opening angle (16) of 180°.
8. Traverse (4) according to one of claims 1 to 7, characterised in that the longitudinal displacement of the traverse legs (65, 66) in the retracted state is limited by the stop of the feet (39) of the traverse legs (65, 66) on the side rail-side receiving profile (7, 8).
9. Traverse (4) according to one of claims 1 to 8, characterised in that due to its construction in the retracted state, it does not project beyond the external geometry (32) of the ladder (1).

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