Foldable ladder with incorporated handrail

Abstract

A foldable ladder (4) comprising an upper platform (8), a pair of stringers (16, 20) directed parallel to a longitudinal direction (Y-Y) and in turn comprising a pair of front and rear longitudinal beams (24, 28), parallel and mutually hinged by means of steps (32), arranged along a transverse direction (X-X), the steps (32) defining, with said longitudinal beams (24, 28), articulated quadrilaterals configured to allow the foldable ladder (4) to switch from a closed or folded configuration to an open configuration, wherein the longitudinal beams (24, 28) extend from a first end (40), at which at least one support foot (44) is provided, to a second end (48) hinged to said upper platform (8), wherein each stringer (16, 20) is provided with a foldable handrail (52), hinged to the related stringer (16, 20) by means of a pair of uprights (56), so as to form an articulated quadrilateral. The uprights (56) are hinged to the related stringer (16, 20) at lower ends (60) by means of pins (64), said pins (64) being rotatable with respect to the stringer (16, 20) about an axis parallel to the transverse direction (X-X) and being fixed transversely to said lower ends (60), so as to achieve a transverse constraint of the uprights (56) to the stringers (16, 20). The upper platform (8), at each stringer (16, 20), comprises a front seat (76) which slidingly and rotatably houses an intermediate portion (80) of each of said uprights (56) enclosed between the pin (64) and the handrail (52), so as to constrain an extraction movement of the ladder (4) to an opening and lifting movement of the handrails (52). The front seat (76) is delimited, on the side of the stringers (16, 20), by a removable bulkhead (84), so as to allow folding down at least one of said handrails (52).

Description

FOLDABLE LADDER WITH INCORPORATED HANDRAILDESCRIPTIONFIELD OF APPLICATION

[0001] The present invention relates to a foldable ladder and an incorporated handrail for vehicles, typically for freight vehicles, such as trucks, lorries, semi-trailers, trailers and the like, and to a related assembly method of said ladder.BACKGROUND ART

[0002] As is known, vehicles are provided with a ladder, at the loading compartments or boxes, to make it easier for an operator to climb to the loading floor.

[0003] Such ladders are typically provided with one or more steps and are welded to the frame of the vehicle or of the loading platform thereof.

[0004] The fixed ladders of the prior art are subject to considerable wear and deterioration, even because they are fixed and thus exposed to the weather throughout the entire use of the vehicle.

[0005] Therefore, with prolonged use, it often happens that one or more steps can become damaged or detached. If this occurs, the ladder needs to be destructively disassembled, usually by unsoldering or cutting off the ladder walls connected / welded to the vehicle frame.

[0006] In the art, it was thus thought to provide removableladders, which can be removed when they are not needed, so as to limit wear and extend the service life thereof.

[0007] However, it is necessary to provide ladders capable of being assembled and disassembled very quickly because the vehicle driver must be able to access the loading compartment repeatedly during the use of the vehicle and must not waste time in the ladder assembly and storage operations .

[0008] At the same time, removable ladder solutions must also ensure the necessary safety standards, despite the assembly and disassembly speed and simplicity.

[0009] The known solutions include using telescopic ladders which, when not in use, are contained in parallelepiped- shaped structures housed below the loading compartment of the vehicle; thereby, the known ladders do not need to be disassembled / assembled each time and stored into special spaces to avoid unnecessary space requirements. Nevertheless, the known ladders fail to ensure the aforementioned requirements of ease of use, assembly and disassembly speed, while complying with adequate safety standards.

[0010] In particular, in order to comply with safety standards, the ladders must also be provided with handrails on both sides of the ladder, so as to allow the user to firmly rest against them when climbing and / ordescending the ladder.

[0011] The known solutions provide for the arrangement of separate handrails which, once the ladder has been extracted, are fastened to the structure. The operation of assembling and then disassembling the ladder is thus slow and laborious, whereby the operator often avoids assembling the handrails, to the detriment of his / her safety.

[0012] Ladder structures provided with handrails fastened to the foldable structure are also known; however, such solutions are not particularly stable because the handrails, due to weight and space requirements, are often rather thin and if subject to transverse loads, tend to bend in a non-negligible manner, limiting the safety function thereof.

[0013] In order to overcome such a drawback, solutions with reinforced handrails are also known, which however are heavy, cumbersome, and expensive to make.OVERVIEW OF THE INVENTION

[0014] Therefore, the need is felt to solve the drawbacks and limitations mentioned with reference to the prior art.

[0015] Such a need is met by a ladder according to claim 1. DESCRIPTION OF THE DRAWINGS

[0016] Further features and advantages of the presentinvention will be more comprehensible from the following description of preferred, non-limiting embodiments thereof, in which:

[0017] Figure 1 depicts a perspective view, in a folded configuration, of a foldable ladder according to a possible embodiment of the present invention;

[0018] Figure 2 depicts a perspective view, in a partially open configuration, of the ladder in Figure 1;

[0019] Figure 3 depicts a perspective view, in an open configuration, of the ladder in Figure 1;

[0020] Figure 4 depicts a side view, in an open configuration, of the ladder in Figure 1;

[0021] Figure 5 depicts a front view, in an open configuration, of the ladder in Figure 1;

[0022] Figure 6 depicts a top plan side view, in a folded configuration, of the ladder in Figure 1;

[0023] Figures 7-8 depict perspective views, from different angles, in a partially opening configuration, of details of the ladder in Figure 1;

[0024] Figures 9-15 depict different overall and detailed perspective views of a foldable ladder according to a further embodiment of the present invention, in a partial closing sequence of at least one handrail.

[0025] The elements or parts of elements common to the embodiments described below will be indicated by the samereference numerals.DETAILED DESCRIPTION

[0026] With reference to the aforesaid figures, reference numeral 4 indicates a foldable ladder as a whole.

[0027] The ladder 4 can be made of any material; preferably, it is made of a metal material. According to a possible embodiment, the ladder 4 is made of hot-dip galvanized carbon steel. Preferably, the foldable ladder 4 is made of extruded aluminum, as better described below.

[0028] The foldable ladder 4 comprises an upper platform 8 defining a walking surface 12 and a pair of stringers 16, 20 (right and left stringers), each stringer 16, 20 being directed parallel to a longitudinal direction Y-Y and in turn comprising a pair of longitudinal beams (front 24 and rear 28 beams, respectively).

[0029] Said front 24 and rear 28 longitudinal beams are parallel and mutually hinged by means of steps 32 arranged along a transverse direction X-X perpendicular to said longitudinal direction Y-Y.

[0030] In particular, the steps 32 define, with said front and rear longitudinal beams 24, 28, articulated quadrilaterals configured to allow ladder 4 to switch from a closed or folded configuration, in which treads 36 of said steps 32 are arranged parallel to the front andrear longitudinal beams 24, 28, to an open configuration, in which said treads 36 are arranged parallel to said walking surface 12 of the upper platform 8.

[0031] In particular, each step 32 is hinged, by means of four transverse pivots 34, to said two pairs of front and rear longitudinal beams 24, 28 which form the stringers 16, 20 of the foldable ladder 4.

[0032] The front and rear longitudinal beams 24, 28 extend from a first end 40, at which at least one support foot 44 is provided, to a second end 48 hinged to said upper platform 8.

[0033] The hinging between the second end 48 and the upper platform 8 allows the foldable ladder 4 to switch from the folded configuration, in which the stringers 16, 20 are arranged parallel to the upper platform 8 so that the ladder takes a flattened configuration, to the open configuration, in which the stringers 16, 20 are arranged in an inclined position with respect to the upper platform 8, according to a predefined angle.

[0034] According to an embodiment, the front and rear longitudinal beams 24, 28, at said first end 40, have a movement handle 42 for said foldable ladder 4.

[0035] Advantageously, each stringer 16, 20 is provided with a foldable handrail 52, hinged to the related stringer 16, 20 by means of a pair of uprights 56, forexample but not necessarily equal to each other, so as to form an articulated quadrilateral which includes the handrail 52, the two uprights 56, and the stringer 16, 20, or better a front or rear longitudinal beam 24, 28 forming the stringer 16, 20. Preferably, as specified below, the handrail 52 is hinged to the rear longitudinal beam 28 which forms the stringer 16, 20.

[0036] The uprights 56 are hinged to the related stringer 16, 20 at lower ends 60 by means of pins 64.

[0037] In particular, said pins 64 are rotatable with respect to the stringer 16, 20 about an axis parallel to the transverse direction X-X and are fixed transversely to said lower ends 60, so as to achieve a transverse constraint of the uprights 56 with respect to the related stringer 16, 20.

[0038] According to a possible embodiment, said pins 64 are associated with said rear longitudinal beams 28, opposite to the handrails 52 with respect to the front longitudinal beams 24.

[0039] For example (Figure 7), the pins 64 comprise at least one slot 68 defining a housing and fixing seat 70 for the lower ends 60 of the uprights 56.

[0040] For example, said housing seat 70 is delimited, transverse direction X-X, by a pair of rises 72 which make transverse undercuts for the lower ends 60 of theuprights 56.

[0041] According to a possible embodiment of the present invention, the upper platform 8, at each stringer 16, 20, comprises a front seat 76 which slidingly and rotatably houses an intermediate portion 80 of each of said uprights 56 enclosed between pin 64 and handrail 52, so as to constrain an extraction movement of the foldable ladder 4 to an automatic opening and lifting movement of the handrails 52.

[0042] Advantageously, said front seat 76 is delimited, on the side of the stringers 16, 20, by a removable bulkhead 84.

[0043] According to a possible embodiment, said removable bulkhead 84 comprises an extractable pivot 86.

[0044] For example (Figure 9b), said extractable pivot 86 is provided with a cotter pin 88.

[0045] Preferably, said extractable pivot 86 is provided with a threaded tip 89 which screws into a corresponding nut or threaded seat 90 obtained in a bulkhead of said front seat 76.

[0046] According to a possible embodiment, the intermediate portion 80 of each of said uprights 56, enclosed between pin 64 and handrail 52, is provided with a fixing pad 82 provided with an internal thread 83 configured so as to receive by screwing the threaded tip 89 of theextractable pivot 86. After removing the extractable pivot 86 in order to lower at least one handrail 52, the user can thus screw the threaded tip 89 onto the internal thread 83 of the fixing pad 82 in order not to lose the extractable pivot 86 and have it always readily available if he / she decides to restore the handrail 52 itself.

[0047] According to an embodiment, the extractable pivot 86 is also provided with a head 85, opposite to the threaded tip 89, configured to be easily rotated by a tool such as pliers or a wrench; said head 85 is hexagonal, for example. Said head 85 can also be provided with an Allen hole 87 to facilitate the tightening and releasing thereof.

[0048] Since the removable bulkhead 84 can be easily removed, the user can remove the removable bulkhead 84 and allow closing the handrail 52 (Figures 10-15), when needed. Indeed, once the removable bulkhead 84 is removed, the articulated quadrilateral-shaped structure of the handrail is no longer supported by the bulkhead itself and therefore the handrail 52, by gravity, is brought to a parallel position in contact with the stringer 16, 20 upon rotation of the uprights 56 downwards, i.e., towards the stringers 16, 20 themselves.

[0049] For example, the user can decide to fold down both handrails 52 because items having a transverse spacerequirement such as to interfere with the handrails 52 themselves need to be loaded or unloaded into / from the loading compartment of the vehicle.

[0050] Obviously, the user also has the possibility to fold down only one handrail 52 according to contingent needs.

[0051] According to a possible embodiment, the upper platform 8 is delimited transversely by a pair of hollow tracks 92 which, in the folded configuration, house said pairs of stringers 16, 20, i.e., the related front and rear longitudinal beams 24, 28.

[0052] According to a possible embodiment, said hollow tracks 92 each delimit a recess 96 shaped to house and lock the corresponding pin 64 in place. In particular, the engagement of the pin 64 of stringer 16, 20 in the related recess 96 allows locking the ladder 4 in the closed or folded configuration.

[0053] Preferably, the front and rear longitudinal beams 24, 28 of the stringers 16, 20, the handrails 52, and the uprights 56 are made from 'U' profiles, preferably made of extruded aluminum.

[0054] Preferably, the handrails 52 have at least one cantilevered portion 100 with respect to said uprights 56.

[0055] For example, said cantilevered portion extends from the side of the second ends 48 of the longitudinal beams24, 28 so as to create a valid support for the user up to reaching the walking surface 12 of the upper platform 8.

[0056] Preferably, the upper platform 8 is provided with wheels 104 for the translation thereof with respect to the associable vehicle. Preferably, said wheels 104 are associated with the hollow tracks 92.

[0057] According to a possible embodiment, the upper platform 8, close to said wheels 104, is provided with at least one anti-return device 106 of ladder 4. For example, said anti-return device 106 comprises an inclined surface 108 and is provided with a related spring (not shown) which allows the retraction thereof when opening the ladder 4, and the subsequent extraction when the opening end-of-stroke is reached. Once the opening end-of-stroke is reached, an abutment 110, contiguous to the inclined surface 108, prevents the accidental closing thereof by abutting against a related stop (not shown). The closing of ladder 4 can occur only after the previous elastic retraction of the anti-return device 106 so as to release the abutment 110 from the related stop.

[0058] The operation of a foldable ladder according to the present invention will now be described.

[0059] In particular, the foldable ladder 4 is usually on the vehicle in a folded configuration, inside a loadingcompartment of the vehicle (not shown).

[0060] When needed, firstly the user at least partially extracts the foldable ladder 4 from the loading compartment of the vehicle, preferably using the appropriate wheels 104.

[0061] The user then releases the stringers 16, 20 from the upper platform 8 preferably using the movement handles 42.

[0062] In particular, engaging the pin 64 of stringer 16, 20 in the related recess 96 allows locking ladder 4 in the closed or folded configuration.

[0063] Acting on the movement handles 42, the user can tilt the stringers around the hinges thereof with respect to the upper platform 8 so as to release the pins 64 from the related recesses 96.

[0064] The structure of the stringers can then be extracted and rotated downwards so as to allow opening the ladder with related rotation of the steps 32 and distancing of the front 24 and rear 28 longitudinal beams.

[0065] Such an opening movement of the front and rear longitudinal beams 24, 28 also actuates the lifting or opening of the handrails 52 due to the connection between the intermediate portion 80 of the uprights 56, enclosed between pin 64 and handrail 52, and the front seat 76 of platform 8.

[0066] As seen, when needed, the user can decide to remove the removable bulkhead 84 and thus allow closing the handrail 52. Indeed, once the removable bulkhead 84 is removed, the articulated quadrilateral-shaped structure of handrail 52 is no longer supported by the bulkhead itself, and therefore the handrail 52, by gravity, is brought to a parallel position in contact with the stringer 16, 20, upon rotation of the uprights 56 downwards, i.e., towards the stringers 16, 20 themselves.

[0067] As can be appreciated from the above description, the solutions described above allow overcoming the drawbacks introduced in the prior art.

[0068] In particular, the ladder according to the present invention can be opened and closed in a rather practical and quick manner by a single operator, without the use of any specific tools.

[0069] The opening / closing operation can be repeated several times when the vehicle is being used, even on the same day, without slowing down the work activity of loading / unloading goods.

[0070] For example, if a step on the ladder breaks, the operator can easily replace the ladder by easily removing it from the frame of the vehicle, without using specific tools and without having to destroy / remove welded parts.

[0071] The ladder is safe and complies with the necessarysafety standards.

[0072] In particular, the handrails provided are practical, functional, lightweight, and not cumbersome.

[0073] At the same time, the handrails are sturdy because they are correctly guided and fixed to the structure of the ladder stringers. Therefore, the handrails bend in a limited and controlled manner, even when subjected to a heavy transverse load by a user.

[0074] Moreover, as shown, the handrails can be easily folded down in order to improve the space requirements and avoid them from interfering with items to be transported by means of the ladder itself, for example. The folding down of the handrails can also be asymmetrical.

[0075] Finally, the structure of the foldable ladder is lightweight and affordable to make.

[0076] In order to meet contingent, specific needs, those skilled in the art may make several changes and variations to the solutions described above.

[0077] The scope of protection of the invention is defined by the following claims.List of reference signs.4: ladder8: upper platform12: walking surface16, 20: stringers24: front longitudinal beams28: rear longitudinal beams32: steps34: transverse pivots36: treads40: first end42: movement handle44: support foot48: second end52: handrail56: uprights60: lower ends64: pins68: slot70: housing seat72: rises76: front seat80: intermediate portion82: fixing pad83: internal thread84: removable bulkhead85: head86: extractable pivot87: Allen hole 88: cotter pin89: threaded tip90: nut or threaded seat92: hollow tracks96: recess 100: cantilevered portion104: wheels106: anti-return device108: inclined surface110: abutment Y-Y: longitudinal directionX-X: transverse direction

Claims

CLAIMS1. A foldable ladder (4) comprising:- an upper platform (8) defining a walking surface (12),- a pair of right and left stringers (16, 20), each stringer (16, 20) being directed parallel to a longitudinal direction (Y-Y) and in turn comprising a pair of longitudinal beams (24, 28) - front and rear beams, respectively - parallel and mutually hinged by means of steps (32), arranged along a transverse direction (X-X) perpendicular to said longitudinal direction (Y-Y), the steps (32) defining, with said longitudinal beams (24, 28), articulated quadrilaterals configured to allow the foldable ladder (4) to switch from a closed or folded configuration, in which treads (36) of said steps (32) are arranged parallel to the longitudinal beams(24, 28), to an open configuration, in which said treads (36) are arranged parallel to said walking surface (12) of the upper platform (8),- wherein the longitudinal beams (24, 28) extend from a first end (40), at which at least one support foot (44) is provided, to a second end (48) hinged to said upper platform (8),- wherein each stringer (16, 20) is provided with a foldable handrail (52), hinged to the related stringer (16, 20) by means of a pair of uprights (56), so as toform an articulated quadrilateral,- said uprights (56) being hinged to the related stringer (16, 20) at lower ends (60) by means of pins (64), said pins (64) being rotatable with respect to the stringer (16, 20) about an axis parallel to the transverse direction (X-X) and being fixed transversely to said lower ends (60), so as to achieve a transverse constraint of the uprights (56) to the stringers (16, 20), wherein the upper platform (8), at each stringer (16, 20), comprises a front seat (76) which slidingly and rotatably houses an intermediate portion (80) of each of said uprights (56) enclosed between the pin (64) and the handrail (52), so as to constrain an extraction movement of the ladder (4) to an opening and lifting movement of the handrails (52), wherein said front seat (76) is delimited, on the side of the stringers (16, 20), by a removable bulkhead (84), so as to allow folding down at least one of said handrails (52).

2. A foldable ladder (4) according to claim 1, wherein said removable bulkhead (84) comprises an extractable pivot (86).

3. A foldable ladder (4) according to claim 2, wherein said extractable pivot (86) is provided with a threaded tip (89) which screws into a corresponding nut orthreaded seat (90) obtained on a bulkhead of said front seat (76).

4. A foldable ladder (4) according to claim 3, wherein the intermediate portion (80) of each of said uprights (56), enclosed between the pin (64) and the handrail (52), is provided with a fixing pad (82) provided with an internal thread (83) configured so as to receive by screwing the threaded tip (89) of the extractable pivot (86).

5. A foldable ladder (4) according to claim 3 or 4, wherein the extractable pivot (86) is provided with a head (85), opposite to the threaded tip (89), configured to be rotated by a tool such as pliers or a wrench.

6. A foldable ladder (4) according to claim 5, wherein said head (85) is provided with an Allen hole (87) to facilitate the tightening and releasing thereof.

7. A foldable ladder (4) according to any one of claims 2 to 6, wherein said extractable pivot (86) is provided with a cotter pin (88).

8. A foldable ladder (4) according to any one of claims 1 to 7, wherein said pins (64) are associated with said rear longitudinal beams (28), opposite to the handrails (52) with respect to the front longitudinal beams (24).

9. A foldable ladder (4) according to any one of claims 1 to 8, wherein said pins (64) comprise at least one slot(68) defining a housing seat (70) for fixing the lower ends (60) of the uprights (56).

10. A foldable ladder (4) according to claim 9, wherein said housing seat (70) is delimited, transverse direction (X-X), by a pair of rises (72) which make transverse undercuts for the lower ends (60) of the uprights (56).

11. A foldable ladder (4) according to any one of claims 1 to 10, wherein the upper platform (8) is delimited transversely by a pair of hollow tracks (92) which, in a folded configuration, house said pairs of stringers (16, 20).

12. A foldable ladder (4) according to claim 11, wherein said hollow tracks (92) each delimit a recess (96) shaped to house and lock the corresponding pin (64) in place.

13. A foldable ladder (4) according to any one of claims 1 to 12, wherein the front and rear longitudinal beams (24, 28), at said first end (40), have a movement handle (42) for said foldable ladder (4).

14. A foldable ladder (4) according to any one of claims 1 to 13, wherein the front and rear longitudinal beams (24, 28) of the stringers (16, 20), the handrails (52), and the uprights (56) are made from 'U' profiles, preferably made of aluminum.

15. A foldable ladder (4) according to any one of claims 1 to 14, wherein the handrails (52) have at least onecantilevered portion (100) with respect to said uprights (56).

16. A foldable ladder (4) according to any one of claims 1 to 15, wherein the upper platform (8) is provided with wheels (104) for the translation thereof with respect to the associable vehicle.

17. A foldable ladder (4) according to claim 16, wherein the upper platform (8), close to said wheels (104), is provided with at least one anti-return device (106) of the ladder (4).

18. A foldable ladder (4) according to claim 17, wherein said anti-return device (106) comprises an inclined surface (108) and is provided with a related spring which allows the retraction thereof when opening the ladder (4) and the subsequent extraction when an opening end-of- stroke is reached.

19. A foldable ladder (4) according to claim 18, wherein said anti-return device (106) comprises an abutment (110), contiguous to the inclined surface (108), configured so that when the opening end-of-stroke of the ladder (4) is reached, it prevents the accidental closing thereof, abutting against a related stop.

20. A foldable ladder (4) according to any one of claims 1 to 19, wherein each step (32) is hinged, by means of four transverse pivots (34), to said two pairs of frontand rear longitudinal beams (24, 28) which form the stringers (16, 20) of the foldable ladder (4).

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