EA012890B1 - Collapsible combination ladder - Google Patents

Abstract

A collapsible stepladder (1) comprising two ladder legs (2, 3), where the legs (2, 3) are hingedly connected to each other in one end. Each of the ladder legs (2, 3) comprises several ladder sections (4a-4d) , and where each section comprises two ladder bars (6, 7) arranged parallel to each other and interconnected at one end by a rung (8) to form a U-shaped ladder section. The ladder sections are telescopically inserted into a lower ladder section (4e) to form a collapsible ladder comprising at least three ladder sections. One of the ladder legs (3) is provided with a support part (12) in one end. The support part (12) is telescopically extendible from the ladder leg (3) and forms an extension ladder of the ladder leg and where the support part (12) projects above a hinge (5) between the two ladder legs (2, 3).

Description

This invention relates to a folding stepladder equipped with ladder sections, telescopically inserted into each other.

The level of technology

Folding and sliding stepladders are known in the art. Below is a description of examples of ladders, according to the prior art.

In νθ-Α1-99 / 51848 a telescopically foldable stepladder is disclosed, containing two uprights that are hinged to each other. Each rack is made of telescopically folding sections, with snap mechanisms in each of the steps for automatically locking the sections relative to each other when the rack is extended. Snap mechanisms in each step are designed to release the next higher section when the step is folded to the next lower step. The distance between the steps of one of the uprights, when the stepladder is lengthened, is greater than the distance between the steps in the other upright. The disadvantage of the stepladder disclosed in \ νθ-Λ 1-99 / 51848 is that the folding sections of the two racks have different heights, so that the stepladder will never pass certification. In addition, the ladder can not be converted into a straight staircase, because folding two racks next to each other leads to the formation of a staircase with many small steps due to the different height of the folding sections.

In ϋδ--4989692, a ladder is disclosed that includes two pivotally connected sections that can be oriented in an inverted U-shaped configuration for use as a ladder, or into a straight linear configuration for use as a straight ladder. Each section of the staircase includes several V-shaped support blocks, each of which forms a crossbar and two side bars extending downwards. The side bars of different ϋ-shaped blocks have calibrated cross-sectional dimensions, so that the blocks can be folded by telescoping sliding side bars inside each other. The disadvantage of the ladder uncovered in ϋδ-894989692 is the impossibility of using it without an external support, or the user needs to maintain balance during operation, which is not preferable from the point of view of safety. This is due to the lack of support provided on the stairs when using the upper sections of the stairs. Another disadvantage of the ladder is that if the ladder is transformed into a straight ladder, the ladder is rather unstable, since the two racks are folded and connected to each other using a swiveling connecting rod 26. Such a fixation system is not very reliable and not very stable and will not pass certification.

OV-L-2110286 disclosed another ladder, including the first set of durable and telescopic elements, the second set of parts, each of which contains a supporting surface forming the step of the ladder. Each part is transversely connected to one element or a group of strong elements of the first set. A set of locking pins and locking means between the various strong elements of the first set is used to ensure at least the stability of the two extreme positions of the ladder, i.e. when folding the ladder and straightening the ladder. The stepladder disclosed in ОВ-Л2110286 not only has the same drawbacks as disclosed in ϋδ-Ά-4989692, but also does not have a locking or locking system in the transformed position.

The purpose of this invention is to overcome the disadvantages and problems of stepladders, according to the prior art, and the creation of a stepladder that is simple and reliable in handling and which can be converted into a straight staircase without reducing safety standards and the ability to handle it.

Summary of Invention

Stepladder with distinctive features of paragraph 1 of the claims eliminates the above problems.

The features of the dependent claims define additional aspects of the invention and preferred embodiments.

Brief Description of the Drawings

Below is a detailed description of the invention with reference to the accompanying drawings, which depict:

FIG. 1 - the most folded stepladder according to the invention, in isometric projection;

FIG. 2 - step-ladder according to the invention, in which all sections of the stairs are fully extended, in isometric projection;

FIG. 3 - step-ladder according to the invention, in which all sections of the ladder are fully extended, side view;

FIG. 4 shows a step-ladder according to the invention in a transformed form as a straight staircase having one folded section, in an isometric view;

FIG. 5 shows a stepladder according to the invention in a transformed form as a straight staircase having one folded section, side view;

FIG. 6 shows a step-ladder according to the invention, provided with a locking device, where all sections of the ladder are fully extended, side view; and FIG. 7-8 - step-ladder according to the invention, equipped with a locking device, where all sections

- 1 012890 stairs fully retracted, side view.

Detailed description of embodiments

The drawings show a folding ladder 1 according to the invention. FIG. 1 shows a folding ladder 1 containing a first staircase 2, which is pivotally connected to a second staircase 3 at the upper ends of the first and second staircase 2, 3 by means of a hinge 5. Each of the staircase racks 2, 3 contains several stair sections 4a 46, with each ladder section 4a-46 containing two ladder bends 6, 7 arranged parallel to each other and connected to each other by a step 8 with the formation of a образ-shaped ladder section 4a-46. Ladder sections 4a-46 are telescopically inserted into the lower ladder section to form a folding ladder rack 2, 3. Ladder racks 2, 3 additionally contain a lower ladder section 4e, which contains two ladder elbows 6, 7 arranged parallel to each other and connected at the upper end step 9 and at the lower end of the base 10 of the ladder and between the step 9 and the base 10 of the ladder another step 11. The ladder sections 4a-46 are telescopically inserted into the ladder section 4e.

The ladder sections 2, 3 should contain at least three ladder sections 4a-4e, but in the preferred embodiment, the four foldable ladder sections 4a-46 are located together with the lower ladder section 4e. The number of sections is limited by the stability of the ladder and certification requirements.

Each step 8, 9 contains a holding mechanism for automatically locking the sections relative to each other when the stair racks 2, 3 are extended. The retention mechanism may be of any kind known in the art, for example, the retention mechanism shown in EP-B1-0 527 766 or EP-A1-1 402 143.

The second staircase 3 is provided at one end with a support part 12. The support part 12 telescopically extends from the second staircase 3 with the formation of a stair extension 12 of the staircase 3, and the support part 12 protrudes above the hinge 5 between the two stair racks 2, 3. The support part 12 comprises at least one support section 12a-12b, each supporting section comprising two ladder bends 6, 7 arranged parallel to each other and connected at one end by a step 16 to form at least one th образ -shaped support section 12a-12b. The support sections 12a-12b are telescopically inserted into the staircase 3 to form a folding support part 12. The support part 12 also contains an upper support section 12c comprising two ladder bends 6, 7 arranged parallel to each other and connected to each other at one end by a step 13 with the formation of a ϋ-shaped support section 12c. The support section 12c is telescopically inserted into the lower support section 12a-12b.

FIG. 2 shows a ladder in which both ladder posts 2, 3 and the support or extension part 12 are fully extended. The supporting part 12 allows the stepladder user to stand on the upper ladder section 4a-4b, since the supporting part 12 gives the user a sense of security. FIG. 2, the supporting part 12 comprises two folding ladder sections 12a and 12c. A device for holding tools or objects, such as a pallet, table, shelf, box or basket, may be located on the upper step 13 of the support part 12. The device may be clamped, compressed, suspended, engaged or otherwise positioned on the upper step 13. Step 13 may be provided with receiving means, such as holes, grooved surfaces, recesses or the like, for better placement of the restraint.

FIG. 2 also shows a tape 14 located between the uprights 2, 3 to increase the stability of the stairs in the extended or folded state and to prevent the staircase from moving apart from each other. The tape 14 is attached using suitable fastening means, for example, rivets or the like, at one end to the back side of the step 8 of the stair stand 2, and at the other end to the rear side of the step 8 of the stair stand 3. The tape 14 is preferably attached to the steps 8, located in the ladder section 4e of the ladder racks 2, 3, respectively, however, the tape 14 can also be attached to the steps belonging to the ladder sections located above or below the ladder sections 4e. The tape 14 is also shown in FIG. 3 and 5, but not shown in FIG. 1 and 4 for clarity. The tape 14 may be made of woven nylon material.

FIG. 3 shows how the hinge connection 5 almost forms a platform between the upper part of the stair racks 2, 3, which can be used to position a tool box or the like. or for standing on it.

FIG. 4 and 5, the ladder section 46 of the ladder rack 2 is folded. Stepladder 1 is transformed into a straight staircase, which is leaning against the wall. The supporting part 12 allows you to lean the ladder against the wall without creating interference from the side of the ladder rack 2 or reducing the stability of the ladder in the leaning position. Since the staircase section 46 is folded, the staircase 2 weighs freely and does not create interference when the ladder is transformed into a straight staircase. It is possible to fold one or more foldable ladder sections 4a-46. To ensure the elimination of the extension of the folded ladder sections under its own weight, the holding means 15 holds together the folded ladder sections and the ladder section located directly below the folded

- 2 012890 ladder sections.

FIG. 4, the holding means is a tape 15 of nylon material, but it can also be a hook that is attached to a step of the ladder section and which can be rotated so that the hook partially covers the step of the adjacent ladder section. You can also use an I-shaped clip made of plastic material that holds together the steps of the folded ladder sections and the ladder section located directly below the folded ladder sections. The advantage of clamping is that any of the ladder sections 4a-46 can be folded and held with a clamp, while the location of the hook or ribbon determines which of the folded ladder sections 4a-46 should be folded and held together with the foldable ladder located directly below section. According to another alternative embodiment, the holding mechanism or, in particular, the locking pins of the holding mechanism can be used to lock the folded folding ladder sections 4a-46 relative to the ladder section located directly below the folded ladder section 4a-46.

FIG. 4 and 5, the ladder section 46 is folded, and the tape 15, i.e. the holding means encompasses the folded ladder section 46 and the ladder section 4e of the ladder rack 2. The tape 15 is preferably attached to one of the steps 8, 9 and is long enough to cover the steps of the folded ladder sections and the steps of the ladder section located immediately below the folded ladder sections. In the embodiment shown in FIG. 4 and 5, the tape 15 is attached to the step 9 using a rivet or any other suitable fastening means. The tape 15 is attached in the center of the tape 15, so that the tape extends substantially equally in both directions from the attachment point. In the end parts of the tape 15, U1sgo © or similar fasteners are provided, which cooperate with each other when the ends of the tape surround the steps.

The ladder sections 4b-4e of the ladder rack 3 are preferably made with deeper steps 8, 9, 11 (see Fig. 3 and 5) to provide additional support for the legs compared with the steps of the ladder sections of the ladder rack 2. The steps are preferably made of extruded aluminum profile .

In the above embodiment of the converted staircase, i.e. when using a ladder in the form of a straight ladder, at least one folding ladder section 4a-46 of the first ladder rack 2 is folded to ensure that the ladder is used as a straight ladder. However, it is possible to keep all the stair sections 4a-46 of the first staircase 2 extended and fold the staircase 2 with an arrangement adjacent and parallel to the second staircase 3. In this case, the retaining means 15 can be used to hold two staircase racks 2, 3 in an adjacent and parallel position . In this case, the lower stair section 4e of the second staircase 3 may be longer than the lower staircase section 4e of the first staircase 2, so that both lower end parts of the two stair racks 2, 3 simultaneously rest on the ground.

FIG. 6-8 show a folding stepladder with fewer foldable ladder sections and equipped with a locking device 20. The locking device 20 comprises a first part 21 and a second part 22. The first part 21 is rotatably connected to the step 8 of the first stair strut 2 at one end, preferably with the step 8 of the ladder section located near and below the hinge 5. The second part 22 is similarly connected with the possibility of turning with the corresponding step 8 of the second stair stand 3 on one Onze, preferably with a step ladder section 8, situated near and below the articulation 5. The other ends of the first and second portions 21, 22 are connected with each other, with locking and folding. At the junction between the first and second parts 21, 22 there is also a locking part 23 having a handle 24 protruding upward.

The locking device 20 serves to ensure that the ladder racks 2, 3 stepladders 1 will not inadvertently fold during the use of the ladder 1. When the foldable ladder sections of the ladder 1 are extended and the fully extended ladder racks 2, 3 are deployed to the use position, the first and second parts 21, 22 of the locking device 20 are decomposed with the formation of an almost straight and horizontal part between the steps 8 of the respective ladder sections of the ladder 1. By pulling the locking part 23 upward with n using the arm 24, the first and second parts 21, 23 of the locking device 20 are locked relative to each other by the locking part 23 and any external force of normal size acting on the step ladder 1 does not result in folding of the stair racks 2, 3 together and does not pose a threat to user stepladder

1. In FIG. 6, the locking device 20 is in the locked position.

To unlock the locking device 20, the handle 24 is pushed down, which causes the ends of the first and second parts 21, 22 of the locking device 20 to move downwards and ensures that the stair racks 2, 3 are folded together, if desired.

Since the locking device 20 is located completely inside the ladder bends 6, 7, the locking device 20 is protected from external forces when handling the stepladder 1. In addition, since the first and second parts 21, 22 of the locking device 20 are located on a small opening the short ends of the steps 8, the locking device 20 can be folded without interfering with the telescopic folding of the ladder 1, but the locking device 20 will follow the ladder sections down when the ladder sections are folded. FIG. 7 and 8 clearly show that the locking device 20 is located inside the space defined by the ladder racks 2, 3, in particular, by the knees 6 or 7 of the ladder racks 2, 3, and by the steps 8 of the ladder sections.

The invention is not limited to the embodiments described above and which are shown in the drawings, but may be supplemented and modified in any manner within the scope of the invention defined by the attached claims.

Claims (14)

CLAIM 1. Foldable stepladder (1), containing the first and second staircase (2, 3), with the rack (2, 3) pivotally connected to each other at one end, and each of the stair racks (2, 3) contains several staircase sections (4a-4e), and each section (4a-4b) contains two ladder bends (6, 7) arranged parallel to each other and connected to one another at one end by a step (8) with the formation of an I-shaped staircase section, except In addition, each ladder section (4a-4b) is telescopically inserted into the lower ladder section to form a foldable ladder. containing at least three ladder sections, while the second ladder (3) is provided with a supporting part (12) at one end, while the supporting part (12) is adapted to telescopically extend from the ladder (3) to form a continuation of the ladder rack (3), while the supporting part (12) protrudes above the hinge (5), connecting with each other two stair racks (2, 3), characterized in that the folding stepladder (1) is designed to convert into a straight staircase with independent adjusting its length. 2. Foldable stepladder (1) according to claim 1, in which the first staircase (2) is provided with restraining means (15) for keeping one or more folding sections (4a-4b) in the folded state. 3. Foldable stepladder (1) according to claim 2, in which the holding means (15) is a tape or hook attached to one of the ladder sections (4a-4e) of the first ladder rack (2) for holding the folded ladder section (4a-4b ) together with the ladder section located directly under the folded ladder section (4a-4b). 4. Foldable stepladder (1) according to claim 2, in which the holding means (15) is a-shaped clip, designed to hold together the steps (8, 9) of the folded ladder sections (4a-4b) and the ladder section located directly below folded ladder section (4a-4b). 5. Foldable stepladder (1) according to claim 1, in which the foldable stepladder is configured to transform into a straight ladder using pivotally connected ladder racks (2, 3), ensuring a parallel arrangement of the fully extended ladder racks (2, 3). 6. The folding ladder (1) according to claim 5, in which the lower ladder section (4e) of the second ladder rack (3) is longer than the lower ladder section (4e) of the first ladder rack (2). 7. Foldable stepladder (1) according to any one of claims 1 to 6, in which the supporting part (12) comprises at least one foldable ladder section (12a, 12b, 12c). 8. Foldable stepladder (1) according to any one of claims 1 to 7, in which the supporting part (12) is provided with means for holding tools, paint and other working materials. 9. Foldable stepladder (1) according to any one of claims 1 to 8, in which the two stair racks (2, 3) are connected by a flexible link (14) provided between the respective stair sections (4b-4b) of the stair racks to prevent the stair racks from moving apart (2, 3) stepladders during use. 10. Foldable stepladder (1) according to any one of claims 1 to 9, in which two ladder racks (2, 3) are connected by a locking device (20) provided between the respective ladder sections (4-546) of the ladder racks to prevent movement of the ladder racks (2 , 3) ladders relative to each other during use. 11. Foldable stepladder (1) of claim 10, in which the locking device (20) is located with the fastening to rotate one end of the first and second parts, respectively, on one side of the respective steps of the respective ladder sections (4b-46) of two ladder racks (2, 3), and the first and second parts are connected to each other with the possibility of locking and folding at the other end. 12. The folding ladder (1) according to any one of claims 10 or 11, in which the locking device (20) is intended to be folded, so that the locking device (20) in the folded state is stored in the space between the uprights (2, 3). 13. Foldable stepladder (1) according to any one of claims 1 to 12, in which at least one of the ladder racks (2, 3) of the stepladder is provided with means (10) for improving lateral stability. 14. Foldable stepladder (1) according to claim 13, in which the stabilizing means is the base (10) of the ladder attached to the lower end of the ladder bends (6, 7) of the lowermost sections (4e) of the ladder rack and passing between the ladder bends. - 4 012890