EP1980707A1

EP1980707A1 - Foldable ladder with flexible handle

Info

Publication number: EP1980707A1
Application number: EP07105888A
Authority: EP
Inventors: Claudio Rossi Detto Baldin; Milena Santini
Original assignee: Di Maros Rossi Claudio
Current assignee: Di Maros Rossi Claudio
Priority date: 2007-04-10
Filing date: 2007-04-10
Publication date: 2008-10-15

Abstract

Foldable ladder (10; 10') comprising a pair of spaced front legs (12,14; 12',14') and a pair of spaced rear legs (16,18; 16',18') pivotally mounted on an upper portion of the corresponding front legs. A flexible brace (24; 24a') connects front legs to the corresponding rear legs and is tightened in the unfolded operative position to limit excessive opening of the ladder when a user is on it. The flexible brace (24; 24a') is loose in the folded inoperative position and engages a hook (30; 30') spaced from said flexible to form a handle for carrying said ladder in the horizontal position. (Fig. 1)

Description

The present invention relates to a foldable ladder with a flexible handle.
Foldable ladders or step stools provided with handles are known in the art.
US 7,104,362 B2 discloses a foldable ladder provided with a carrying handle for use when the ladder has been folded to assume a collapsed position. Such handle is pivotally mounted on a retainer member to lock the front and rear legs of the ladder in the folded position. The lock and handle assembly disclosed in this patent comprises several components, including movable parts, which makes the structure of the handle relatively complex and expensive. Also, the lock and handle assembly projects from one side of the ladder, which increases the overall size of the ladder.
WO 99/47783 discloses a foldable ladder provided with a handle to enable carrying the ladder at near its midpoint in height. Also, the handle provides for an indicator for moving the ladder from its unfolded position to its stored position. The handle is positioned in the top step so that the ladder is carried in a vertical position, with the top part of the ladder above the top step that interferes with the arm and shoulder of the person that carries it.
Moreover, the ladders disclosed in the documents mentioned above are not of the type comprising braces or other elements connecting the front and rear legs of the ladder to limit excessive opening of the same.
There remain, thus, several disadvantages to, or problems not solved by, the ladders or step stools disclosed in the cited references. Therefore, the need is felt for a ladder that is provided with a handle which allows convenient carrying of the ladder, is relatively simple and not expensive, and does not undergo excessive opening in the unfolded operative position, particularly when a user is on the ladder.
Therefore the present invention relates to foldable ladder comprising:

a pair of spaced front legs with at least one step extending in-between and a pair of spaced rear legs pivotally mounted on an upper portion of the corresponding front legs, said front and rear legs being aligned in a folded inoperative position;
a flexible brace connecting at least one of said front legs to the corresponding rear leg, said flexible brace being tightened in the unfolded operative position and being loose in the folded inoperative position;

The invention is illustrated below also by means of the attached drawings, which show some preferred but non-limiting embodiments of the invention, in which:

Figure 1 is a perspective view of a first embodiment of the ladder of the invention;
Figure 2 is a partially sectioned side view of the embodiment of Fig. 1;
Figures 3 and 4 are enlarged side views of parts of the ladder of Figures 1 and 2 in different positions;
Figure 5 is a perspective view of part of the ladder of Figures 1-4 in a carrying position;
Figure 6 is a perspective view of a second embodiment of the ladder of the invention;
Figure 7 is a partially sectioned side view of the embodiment of Fig. 6;
Figure 8 is a perspective view of part of the ladder of Figures 6-7 in a carrying position.

With reference to Figure 1 and 2, a ladder 10 is shown in the operative unfolded or open position. Ladder 10 comprises a pair of spaced front legs 12, 14 and a pair of spaced rear legs 16, 18. Steps 13, 15, 17 extend between and are fixed to front legs 12, 14. Of course, more than three steps are possible, depending on the desired height for the ladder. The top step 17 is usually larger than lower steps 13, 15, to provide a safe and comfortable support for a person using the ladder for any kind of work. Rear legs are pivotally mounted on an upper portion of the corresponding front legs via L-shaped end portions 19, 19', provided with holes housing pins 20, 20', extending also into corresponding aligned holes (not shown) of the front legs. Therefore rear leg 18 is pivotally mounted on front leg 14 and rear leg 16 is pivotally mounted on front leg 12.
Typically, top step 17 is pivotally mounted on front legs 12, 14, so that it tilts from a position aligned with the front legs when the ladder is folded, to a horizontal position when the ladder is in the unfolded operative position, wherein top step 17 rests on a transverse rod (not shown) connecting rear legs 16, 18, as known in the art. Suitable coupling of top step 17 to said transverse rod represents also a means to prevent accidental excessive opening of the ladder in the unfolded open position. Such coupling alone, however, could not be sufficient to ensure that no further opening of the ladder occurs.
The front and rear legs are aligned in a folded inoperative position, thanks to the pivotal connection via pins 20, 20'.
Front legs 12, 14 and rear legs 16, 18 are connected at approximately mid length by a flexible brace 24, fixed to the rear legs for example by means of rivets 26. Said flexible brace is for example a bent, or a rope, made by a material which is flexible but non elastic, and has sufficient mechanical resistance to stress. Suitable materials are textile bands woven from suitable yarns or thread, including synthetic resins, metal bents, or ropes.
In a preferred embodiment of the invention, at least front legs 12, 14 are hollow. Flexible brace 24 comprises a portion 24a that extends from rear leg 16 toward front leg 12, which is provided with a transverse hole 28 (shown in Figures 3 and 4) in correspondence of mid step 15. This latter is hollow, too, as better shown in Fig. 2. Flexible brace 24 then enters said transverse hole of front leg 12, which communicates with hollow step 15, and is housed in hollow step 15, as shown in Fig. 1. Then it comes out from hollow step 15 through hole 28' of front leg 14 and comprises a portion 24b which is fixed to rear leg 18 by a rivet not shown but corresponding to rivet 26 of rear leg 16. The primary function of flexible brace 24 is that of preventing accidental excessive opening of the ladder in the unfolded operative position, which would represent a risk to the safety of a person using the ladder. Therefore, brace 24 is tightened between front and rear legs in the unfolded operative position.
When ladder 10 is in the folded inoperative position, as shown in Figures 3 and 4, the front and rear legs are aligned and the portions of brace 24a, 24b between them are loose, since their length exceeds the distance between holes 28, 28' and the corresponding fastening point on the rear leg, which are now close to each other. Brace 24 can thus be pulled by a user of the ladder to one side of the ladder so that also the opposite loose portion of brace 24b is brought to the same side of the ladder. A hook 30 projects from front leg 12 toward rear leg 16 at a point longitudinally spaced from hole 28 of a distance not exceeding half length of the loose portion 24a of brace 24. Thanks to its flexibility, such loose portion of flexible brace 24 is bent and hooked to hook 30 to form a flexible handle for carrying ladder 10, as shown in Fig. 5.
Preferably, the location of hole 28 and the location of hook 30 on front leg 12 is such that the centre of gravity of the ladder in the folded inoperative horizontal position falls in the portion of leg 12 in-between. This feature helps to maintain the ladder balanced and substantially parallel to the ground when it is carried by a user, as shown in Fig. 5. Also, the three point connection of brace 24a to hole 28, rivet 26 and hook 30 maintains the ladder folded during carrying and prevents accidental opening.
With reference to Figure 6 and 7, a ladder 10' according to another embodiment of the invention is shown in the operative unfolded or open position. Ladder 10' has substantially the same structure and design of ladder 10 described above, with the difference that it comprises two separate braces 24a' and 24b' instead of a single brace as in the previous embodiment. Brace 24a' is fastened to front leg 12' and rear leg 16', and brace 24b' is fastened to front leg 14' and rear leg 18', typically by rivets 36. A hook 30' projects from a portion of front leg 12' longitudinally spaced from hole 28 of a distance not exceeding half length of the loose portion of brace 24. As disclosed above, the centre of gravity of the ladder when folded and in a horizontal position falls between hook 30' and the fastening point of brace 24a' to front leg 12'.
When ladder 10' is in the folded inoperative position brace 24a' and 24b' are loose. In such condition, brace 24a' is folded and hooked to hook 30', as shown in Fig. 8, similarly to what shown in Figures 3 and 4. This allows to conveniently carry the ladder, which is also kept in the folded position by the three points connection represented by hook 30' and the rivets 36 fastening the ends of brace 24a' to front and rear legs 12', 16', correspondently.
It is apparent from the description above that the ladder according to the invention can be conveniently carried by a simple and inexpensive flexible handle. Also, such handle does not increase the overall size of the ladder, and performs the function of limiting excessive opening of the ladder in the unfolded operative position. Thus, it performs two functions, thereby allowing to reduce the manufacturing cost.
Of course numerous modifications and variants are possible within the scope of the appended claims. For example, hook 30, 30' can be replaced by any suitable means providing a temporary fastening of brace 24, 24a' when the ladder is folded, so that a handle is formed for carrying purposes. Such fastening is intended to be temporary since brace 24, 24a' is disengaged from such fastening means when the ladder is in the open, operative position, and is straightened to ensure a protection against excessive undesired opening of the ladder.

Claims

Foldable ladder (10; 10') comprising:
- a pair of spaced front legs (12,14; 12',14') with at least one step (15; 15') extending in-between and a pair of spaced rear legs (16,18; 16',18') pivotally mounted on an upper portion of the corresponding front legs, said front and rear legs being aligned in a folded inoperative position;

- a flexible brace (24; 24a') connecting at least one of said front legs (12; 12') to the corresponding rear leg (16; 16'), said flexible brace (24; 24a') being tightened in the unfolded operative position and being loose in the folded inoperative position;
characterised in that said front (12; 12') or rear leg connected by said flexible brace (24; 24a') comprises means (30; 30') for temporary fastening said loose brace, said means (30;30') being spaced from said loose brace, whereby said loose brace in the folded inoperative position is fastened to said fastening means to form a handle for carrying said ladder.
Foldable ladder (10; 10') according to claim 1, characterised in that said fastening means (30;30') is spaced from said flexible brace (24; 24a') of a distance which includes the centre of gravity of said ladder (10; 10') when said ladder is in the folded inoperative horizontal position.
Foldable ladder (10; 10') according to claim 2, characterised in that said distance is less than half length of the loose portion of said brace (24a; 24a') of said ladder in the folded inoperative horizontal position.
Foldable ladder (10; 10') according to claim 1, characterised in that said fastening means (30; 30') is a hook.
Foldable ladder (10) according to claim 1, characterised in that said flexible brace (24) is a single brace fastened to said rear legs (16,18) and engaging holes (28,28') of said front legs (12,14), whereby said brace (24) is tightened in the unfolded operative position and forms loose portions (24a,24b) in the folded inoperative position.
Foldable ladder (10) according to claim 5, characterised by comprising a hollow step (15) aligned with said holes (28,28') of said front legs (12,14), whereby the portion of said brace (24) connecting said front legs (12,14) is housed within said hollow step (15).
Foldable ladder (10) according to claim 4, characterised in that said hook (30) projects from said front leg (12).
Foldable ladder (10) according to claim 4 and 7, characterised in that said distance which includes the centre of gravity of said ladder in the folded inoperative horizontal position is the distance between said hook (30) and said hole (28) of said front leg (12).
Foldable ladder (10') according to claim 1, characterised by comprising two flexible braces (24a',24b') of substantially the same length, each of them being tightened in the unfolded operative position and being loose in the folded inoperative position, one of them (24a') being fixed to one (12') of the front legs and the corresponding rear leg (16'), and the other one (24b') being fixed to the other front leg (14') and the corresponding rear leg (18'), said fastening means (30') extending from a portion of front leg (12') longitudinally spaced from the fastening point of said brace (24a') of a distance not exceeding half length of said brace (24a').
Foldable ladder (10') according to claim 9, characterised in that said fastening means (30') is a hook projects from said front leg (12').
Foldable ladder (10') according to claim 10, characterised said distance including the centre of gravity of said ladder (10') in the folded inoperative horizontal position is the distance between said hook (30') and said fastening point of said brace (24a') to said front leg (12').