FOLDING AND TOLDING STAIRCASE

Abstract

A folding and collapsible staircase comprising two stringers (1, 2) connected by treads (3), one (2) of the stringers being movable and collapsible onto the other fixed (1) by rotation in a horizontal plane, its lower end remaining in contact with the ground during the deployment and folding of the staircase, the treads (3) being connected to the stringers by connecting pieces (6, 7) each comprising a vertical axis for rotational mounting on a stringer and a horizontal axis for rotational mounting on a tread (3), these being horizontal when the staircase is in the use position, and vertical when the staircase is folded, the rotations of the treads between their horizontal and vertical positions being synchronized by means such as connecting rods, universal joints (15), corrugated shafts or pairs of meshing bevel gears. Figure to be published for the abstract: Figure 5B

Description

Description Title of the invention: FOLDABLE AND FOLDING STAIRCASE

[0001] | The invention relates to a staircase that can be folded and folded against a support such as a wall, partition or any other fixed element, for example for access to a room attic from a corridor or narrow room, to a mezzanine above the living rooms or when you want to free up the floor space of the staircase. This type staircase is also suitable for "small space" homes. Practical, functional, comfortable, it can be an element of the decor.

[0002] A staircase essentially comprises steps mounted horizontally between two support pieces called stringers, which can form racks whose teeth have horizontal faces supporting the steps and vertical faces de- finishing the height of the steps.

[0003] — Certain known folding and / or retractable stairs are characterized by narrow and uncomfortable steps (ladder type), and are made in several longitudinal sections which slide or fold back on themselves or with stringers made up of crosspieces which tighten to reduce their length, and come together housed high up in a trapdoor. They are not suitable for frequent use and ne- require the use of an accessory to open the trapdoor, grab the staircase and deploy it. They are impractical, noisy and uncomfortable.

[0004] = Another type of folding staircase that can be folded against a wall is described in the patent FR3004202. It offers improved user comfort but must be moved vertically. wedged to be folded against a wall, which requires the use of springs or jacks to compensate for the weight of moving parts and hold them securely the staircase in the folding position against the wall.

[0005] — The present invention aims in particular to avoid the disadvantages of stairs known foldable and collapsible, in order to facilitate their use for frequent use (for a bedroom for example), to reduce noise during maneuvers while offering negligible footprint when folded, and maintaining their decorative aspect.

[0006] It offers a foldable and collapsible staircase comprising steps carried by two stringers, one of which is fixed and the other mobile and can be folded onto the first, ca- characterized in that the movable stringer can be folded by rotation in a horizontal plane on the fixed stringer and its lower end remains supported on the ground during the de- folding and lowering of the staircase and in that each step is connected to the stringers by two connecting pieces each comprising a vertical mounting axis in rotation on a stringer and a horizontal axis of rotational mounting on the step, each step extending horizontally between the stringers when the staircase is deployed in position of use, and vertically when the staircase is in the folded position on the fixed stringer, the staircase comprising means for synchronizing the rotations of the steps between their horizontal position and their vertical position. Thus, when deploying and folding the staircase, its moving parts remain in contact with the ground, so that these maneuvers require very little effort and are very easy to carry out smoothly and silently. In one embodiment, each step is connected by a double-jointed connecting rod to the fixed stringer. Thus, the movement of the movable stringer along a horizontal circular trajectory around the vertical axes connecting the steps to the fixed stringer will cause the steps to rotate around these vertical axes and synchronously the connecting rods will cause the steps to rotate around their horizontal axes connecting them to the stringers, to position the steps horizontally at the end of the movement of the movable stringer corresponding to the deployment of the staircase, and to position them vertically against the fixed stringer at the end of the folding of the movable stringer onto the fixed stringer. In another embodiment, the connecting parts of the steps comprise universal joints with two inclined rotation axes with angles such that the horizontal movement of the movable stringer causes a double synchronous movement of the steps, a horizontal rotation on the fixed stringer and a tilting between a vertical folding position and a horizontal use position. In alternative embodiments, the double movement of the steps in rotation around a vertical axis and a horizontal axis can be achieved and synchronized by means of: - flexible ring ducts and rigid L-shaped axes mounted inside the flexible ducts, - pairs of orthogonal bevel gears of the same diameter engaged with each other, one of which, vertical, is secured to a stringer and the other of which, horizontal, is secured to a step, and means such as, for example, a bracket for holding the bevel gears in engagement, - brackets with two perpendicular wings, one of which carries a vertical mounting axis on a stringer and the other of which carries a horizontal mounting axis on a step, these two axes being offset from each other, the aforementioned articulated connecting rods being mounted between the steps and the fixed stringer. At the end of deployment, the steps come to rest on horizontal parts of the rack of the movable stringer and on stops carried by the fixed stringer. In one embodiment, the movable stringer extends beyond the steps on the support of the fixed stringer in the folded position and the thickness of the staircase against the wall is substantially equal to the sum of the thickness of a step and that of the stringer. mobile. The footprint is therefore small. Alternatively, the movable stringer is placed on a vertical support of the fixed stringer at the end of the steps, so that the footprint in the folded position is further reduced and equal to the thickness of the steps or the movable stringer. Since the movable stringer always remains in contact with the ground during maneuvers, sliding or rolling means, such as a skate, a caster, a motorized roller or the like are advantageously mounted at the lower end of the movable stringer, for smooth, effortless and silent maneuvers of the staircase. The approach of the staircase against the wall is also perfectly stable and fixed. Any intermediate deployment position is also stable and fixed. The staircase according to the invention can also be equipped with a protective railing attached to the movable stringer for the safety of the user. The invention also proposes to equip the top of the staircase with a step nose located at the level of the upper floor, pivoting with the movable stringer without tilting vertically along the wall. This step nose can be the support of a protective barrier which opens when the staircase is deployed and closes when it is folded back against the wall. This barrier also allows the deployment / retraction maneuvers of the staircase to be controlled from the top. The maneuvers of this staircase being strictly horizontal, they are totally compatible with access hatches placed in the ceiling. In another embodiment, the support stops for the steps in the horizontal position provided on the fixed stringer are replaced by slots made in the fixed stringer and associated with fingers at the end of the steps, which engage in the slots during deployment of the staircase and come to bear on the bottom of these slots at the end of deployment. Mechanical or magnetic means for positioning and locking the staircase in the position of use may also be provided to ensure the safety of the user, for example means for hooking and / or locking at least one of the upper and lower ends of the movable stringer in the deployed position. Advantageously, the staircase can be equipped with a handrail mounted to rotate around its axis, for example on the fixed support, to synchronize the movements of the top and bottom of the staircase at the start of deployment. The alignment of all the axes of rotation in this phase could cause the deployment to be blocked if the precaution is not taken to start the deployment synchronously between the top and the bottom of the staircase. When the deployment is initiated by a few degrees (of the order of 5° for example), the steps and the stringers form identical deformable parallelograms which stabilize the rest of the deployment. This mobile handrail, rotating around its longitudinal axis, is equipped with paddles that pass between the support and two end steps, for example. Two handles, one at each end of the handrail, allow it to rotate, thus moving the paddles that push the end steps of the staircase in a synchronized manner. The handrail and the pallets are advantageously returned to the rest position, for example by elastic means, or by a torsion spring placed inside the handrail tube. A rotation stop prevents the pallets from falling off the ends of the steps. The invention will be better understood and other characteristics, details and advantages thereof will appear more clearly on reading the following description, given by way of example with reference to the appended drawings in which: [Fig.1] Views 1A, 1B and 1C represent in a simplified manner the staircase in a folding position against a wall, an intermediate position and a deployment or use position; [Fig.2] Views 2A, 2B and 2C are partial views illustrating the kinematics of deployment of the steps during the horizontal maneuvering of the mobile stringer, in an embodiment comprising articulated connecting rods for tilting the steps; [Fig.3] Views 3A, 3B, 3C and 3D are simplified partial views illustrating the kinematics of deployment of the steps in an embodiment comprising universal joints with two rotation axes for mounting and synchronizing the steps on the fixed stringer; [Fig.4] Views 4A, 4B, 4C, 4D, 4E and 4F represent a gimbal for fixing and synchronizing the step on the fixed stringer, in front, side and top views, in folded and deployed positions, respectively; [Fig.5] Views 5A, 5B and 5C are partial views representing three positions of a gimbal staircase; [Fig.6] Views 6A, 6B, 6C, 6D and 6E show different means of mounting and articulating the steps on the fixed stringer and on the movable stringer: [Fig.7&8] Views 7A and 7B represent the movement of a barrier at the top of the staircase, views 8A and 8B represent means for locking the staircase in the position of use, [Fig.9] Views 9A, 9B, 9C and 9D represent different positions of a means of horizontal support of the steps on the fixed stringer at the end of deployment of the staircase, [Fig.10] Views 10A and 10B represent two positions of a variant embodiment of the staircase; [Fig.11] Views 11A and 11B show the staircase equipped with an active handrail to synchronize and facilitate the start of deployment. [Fig. 1] The horizontally folding and collapsible staircase according to the invention, shown in figures | essentially comprises a fixed stringer 1 in a rack fixed to a vertical wall 8 such as a wall or a partition, a movable stringer 2 in a rack and steps 3 mounted in rotation on the stringers around two axes of rotation (horizontal and vertical) by connecting pieces 6 and 7 which are located at the corners of the step noses (front or user side) and at the corresponding corners of the racks of the fixed and movable stringers. The synchronous tilting of the steps during the deployment and folding of the staircase is ensured by connecting rods 14 fixed by ball joints on the inner side of the fixed stringer and on the underside of the steps 3. At the end of deployment, the steps 3 come into horizontal support on stops 11 of the fixed stringer 1 and on horizontal parts of the rack of the movable stringer 2. The top of the staircase is equipped with a riser 5 integral with the fixed stringer and fixed to the side of the upper floor P, participating in the fixing of the assembly, and a horizontal step nose 4 which pivots on the top of the two stringers, without vertical tilting, and comes to align with the surface of the upper floor P by applying itself to the riser 5. This riser has an extension 10 on which a complementary shaped recess 10a is engaged, made on the top of the movable stringer 2 to ensure rigid support at the end of deployment of the staircase. The base 9 of the movable stringer 2 rests on the ground and is equipped with sliding or rolling means such as a skate, a caster, a motorized roller or the like, to reduce friction and adapt to the type of floor covering. The motorized roller allows automatic deployment and folding of the staircase, for example by means of a remote control. [Fig.2] The operation is illustrated in more detail by views 2A, 2B and 2C. The connecting pieces 7 of the steps on the fixed stringer 1 comprise a vertical axis 7y for mounting on the stringer 1 and a horizontal axis 7x for mounting on a step, these two perpendicular axes being concurrent but able to be offset. The connecting rods 14 with swivel ends are positioned between the fixed stringer 1 and the steps in such a way that they tilt the steps 3 from vertical to horizontal when the steps rotate 90° around the vertical axes 7y of the fixed stringer 1. The connecting pieces 6 of the steps pivot on the movable stringer 2 around the vertical axes 6y and on the steps 3 around the horizontal axes 6x. These perpendicular axes 6x, 6y are offset to allow the movable stringer 2 to be folded down onto the steps 3. The horizontal circular movement of the movable stringer 2 causes the steps 3 to rotate around the vertical axes 6y and 7y and the connecting rods 14 impose a synchronous rotation of the steps 3 around the horizontal axes 6x and 7x. In the deployed position shown in view 2C, the steps 3 come to bear on the stops 11 of the fixed stringer 1 and on the horizontal parts 12a of the rack of the movable stringer 2. [Fig.3] Views 3A, 3B, 3C and 3D schematically illustrate the operation of an embodiment of the invention comprising cardan joints. Each gimbal comprises a support 15 fixedly mounted on the fixed stringer 1 along a vertical axis 15y, an inclined axis 15z integral with the support 15 and an axis 15x perpendicular to the axis 15z and mounted to rotate around the axis 15z. The axis 15x is integral with the end of a step 3 while being oriented at an angle of 45° relative to a large side of the step. The other end of the step 3 is connected to the movable stringer 2 by a joint 6 with two orthogonal axes, a horizontal axis 6x integral with the step 3 and a vertical axis 6y integral with the movable stringer 2. The horizontal circular movement of the mobile stringer 2 will cause a double movement of the step 3 around the gimbal 15, a rotation around the axis 15x which itself rotates around the fixed axis 15z and a tilting around the axis 6x on the mobile stringer 2. The horizontal rotational movement of 90° of the mobile stringer 2 thus causes the synchronous rotation and tilting of 90° of the step 3 around the gimbal 15 of the fixed stringer. [Fig.4] Views 4A, 4B, 4C, 4D, 4E and 4F illustrate in detail the operation of a gimbal model in the folded position (views 4A, 4C and 4E) and in the deployed position (views 4B, 4D and 4F). Views 4A and 4B are front views of the gimbal, views 4C and 4D are side views, and views 4E and 4F are top views. In the embodiment shown, the universal joint comprises a support 15s intended to be fixed on the fixed stringer 1 along the vertical axis 15y, a bearing 15p secured to the support 15s and oriented along the axis 15z inclined at angles œ and B relative to the axis 15y and to the plane of the support 15s, and a trunnion 15t fixed longitudinally to the bearing 15p and rotating around the axis 15z. A rod 15a with axis 15x perpendicular to the axis 15z is carried by the trunnion 15t for mounting a step 3 and is parallel to the plane of the step while being inclined at 45° relative to a large side of the step. The step can therefore rotate around the 15x and 15z axes relative to the fixed stringer 1. When a horizontal trajectory constraint of 90° is imposed on the other end of the step 3 by the mobile stringer 2, the gimbal imposes the combination of rotations around the 15z and 15x axes, which forces the step to tilt from a vertical position to a horizontal position.These starting and finishing positions are regulated by the angles " and B which can have values ​​of the order of 55° and 44° respectively for example. [Fig.5] Views 5A, 5B and 5C show the movements of the steps 3 and the movable stringer 2 in this embodiment with gimbals 15. The rotating axis 15x of each gimbal is parallel to the upper face of the step 3 and inclined by 45° relative to the longitudinal axis of the step. It can be fixed under or at the heart of the step 3. The axis 15x is perpendicular to the rotating axis 15z which connects it to the support 15. The rotating axis 15z can be for example inclined by 55° with respect to the axis 15y. The vertical axis 15y is fixed with respect to the fixed stringer 1. Each step is therefore free to rotate around the axes 15x and 15z. The other end of the step 3 is connected to the movable stringer 2 by a connecting bracket 6 which pivots on the movable stringer around a vertical axis 6y and on the step 3 around a horizontal axis 6x. The two axes 6x, 6y are offset by half the thickness of the step 3 and the movable stringer 2 to allow the movable stringer 2 to be folded down onto the steps 3. The horizontal circular movement of the movable stringer 2 causes the steps 3 to rotate around the axes 6y, the combination of the constrained and synchronous rotations around the axes 15x and 15z causing the steps to move from a vertical position, with the stairs folded down, to a horizontal position, with the stairs deployed for use.In the deployed position, the steps 3 come to rest on the base of the slots 13 of the fixed stringer 1 and on the horizontal parts 12a of the rack of the mobile stringer 2. [Fig.5B] is used for the Abstract. [Fig.6] The views represent variants of the means of connection between the fixed stringer 1 and the steps 3 to synchronize their rotation and their tilting. In views 6A and 6B, two examples of the construction of articulations for a cardan joint 15 are shown, the axes of rotation of which are inclined relative to the fixed stringer 1 and to the step 3 and the operation of which has been described previously. In view 6C, the articulation is achieved by a connection with a flexible ring sheath 16 and a rigid L-shaped axle 17 placed inside the flexible sheath. The well-known properties of these flexible ring sheaths, such as bellows or electrical sheaths, are to have great axial flexibility and a high axial torsional torque. The L-shaped axle 17 is free to rotate but axially locked inside the sheath 16 to maintain an L-shape of the connection. One end of the flexible sheath 16 is secured to the fixed stringer 1, the other end is secured to the step 3.When a rotational movement around a vertical axis imposed by the movement of its other end connected to the movable stringer 2 is applied to the step, the flexible sheath 16 locked in the fixed stringer by one end and in the step by the other end, will make a horizontal axial rotational movement around the L-shaped axis 17 of the same angular value as its rotation around the vertical axis. A rotation of 90° around the vertical axis will therefore cause a rotation of 90° around the horizontal axis and the steps will pass, synchronously, from a vertical position to a horizontal position during the deployment of the staircase and vice versa during the folding of the staircase. In the 6D view, the articulation is achieved by a connection with two bevel gears identical and orthogonal 18 engaged, one secured to the fixed stringer | and the other secured to the step 3. A bracket 19 keeps the two pinions 18 in contact and ensures the connection between the step 3 and the fixed stringer 1. The rotation of the step 3 around a vertical axis induced by the circular movement of the mobile stringer 2 will cause the step to tilt by the same angle around a horizontal axis. View 6E shows a right-angle connection with two offset orthogonal axes 6x and 6y between a step 3 and the movable stringer 2. This passive connection allows the movable stringer 2 to be folded against the steps 3 for folding against the wall. The 6x axis is carried by the step 3 and rotates in a hole in a vertical wing of the right-angle 6. The 6y axis is carried by the movable stringer 2 and rotates in a hole in a horizontal wing of the right-angle 6. [Fig.7&8] Views 7AÀ and 7B show a top view of a barrier 20 secured to the step nose 4, open "on passage" when the staircase is deployed for use and closed "on passage" when the staircase is folded against the wall. This barrier 20 also allows the deployment and folding of the staircase to be manually controlled from the upper floor. Views 8A and 8B show two examples of locking the top of the movable stringer 2 on the riser 5 to secure the use of the staircase and prevent it from deforming under load. In view 8AÀ, V-shapes 10', 10a' are machined, one male on the movable stringer 2 and the other female on the riser 5. In view 8B, magnets 21, such as door magnets, are fixed opposite each other on the riser 5 and on the movable stringer 2. [Fig.9] Views 9A, 9B, 9C and 9D illustrate the kinematics of the movement of the steps 3 relative to the fixed stringer 1, particularly at the end of deployment, using fingers or lugs 22 machined on the steps 3 and slots 13 formed in the fixed stringer 1. At the end of deployment, each finger or lug 22 enters a slot 13 and comes to bear on the bottom of the slot 13. [Fig.10] In an alternative embodiment shown in views 10A and 10B, the articulation points of the steps are located at the rear of the movable stringer 2 so that, in the position of folding against the wall, the fixed stringer 1, the steps 3 and the movable stringer 2 are in the same plane, view 10A. At the end of deployment of the staircase, the fingers 22b of the steps 3 rest on angles 12 fixed on the movable stringer to form horizontal stops for supporting the steps 3. The horizontal stops of the steps 3 on the fixed stringer 1 are formed by the fingers 22A of the steps 3 on the fixed stringer 1 side and by openings 13 in the fixed stringer 1. At the end of deployment of the staircase, the fingers 22a will engage in the openings 13 and come to rest on the base of these openings, as shown in views 9A to 9D. [Fig.11] Views 11A and 11B show an active handrail 23 serving to ensure the uniform start of the deployment of the staircase. The handrail 23 is rotatably mounted around its axis on the fixed support 8 by links 26. Two paddles 24 are fixed to the handrail 23 as well as two manual control handles 25. When the staircase is folded against the support 8, two end steps 3 cover the paddles 24 and an action on one of the control handles 25 causes the handrail 23 and the paddles 24 to rotate, which uniformly push the end steps and the movable stringer 2 by a sufficient amount, for example of the order of 5°, for the deployment to be initiated uniformly. The handrail is returned to its rest position by elastic means or by a torsion spring housed in the tube of the handrail.

Claims

Claims

1. Foldable and folding staircase comprising steps (3) carried by two stringers (1,2) one of which (1) is fixed and the other (2) mobile is ra- beatable on the first, characterized in that the movable stringer (2) is ra- beatable by rotation in a horizontal plane on the fixed stringer (1) and its lower end (9) remains supported on the ground during deployment and the folding of the staircase and in that each step (3) is connected to the stringers (1,2) by two connecting pieces (6,7) each comprising a vertical axis (6y, 7y) for rotating mounting on a stringer and a ho- axis rizontal (6x,7x) for rotating mounting on the step (3), each step (3) extending horizontally between the stringers when the staircase is deployed in the use position, and vertically when the staircase is in the folded position on the fixed stringer (1), the staircase comprising means (14, 15, 18) for synchronizing the rotations of the steps between their horizontal position and their vertical position.

2. Staircase according to claim |, characterized in that the means of synchronization includes connecting rods (14) articulated between the steps (3) and the fixed stringer (1) for the synchronous tilting of the steps (3) between their vertical position when the staircase is folded down against the fixed stringer (1) and their horizontal position when the staircase is deployed in the use position.

3. Staircase according to claim ! or 2, characterized in that the parts (6,7) for mounting the steps (3) on the fixed stringer (1) and / or on the stringer mobile (2) include brackets with two perpendicular wings, of which one receives a vertical axis (6y, 7y) for mounting on a stringer (1, 2) and the other of which receives a horizontal axis (6x, 7x) for mounting on a step (3), these two axes being offset from each other.

4. Staircase according to claim |, characterized in that the parts (7) of mounting of the steps (3) on the fixed stringer (1) includes universal joints with two inclined rotation axes (15x and 15z) relative to one axis fixed vertical (15y), allowing the rotations of the steps to be synchronized (3) when deploying and folding the staircase.

5. Staircase according to claim 1, characterized in that the parts (7) of mounting of the steps (3) on the fixed stringer (1) includes two orthogonal bevel gears (18) meshing with each other, one of which vertical is integral with the fixed stringer (1) and the other horizontal is attached to a step (3), and means, such as for example a square, for holding the bevel gears in engagement for synchronization- nization of step rotations.

6. Staircase according to claim !, characterized in that the parts (7) of mounting of the steps (3) on the fixed stringer (1) includes an axis rigid (17) in L mounted in a sheath (16) with rings, the axis (17) being axially blocked in the sheath (16) one end of which is secured to the fixed stringer (1) and the other end of which is secured to a step (3).

7. Staircase according to one of claims 1 to 6, characterized in that, in their horizontal position, the steps (3) come into horizontal support on stops (11) provided on the fixed stringer (1) and on horizontal parts- zontals (12a) of the mobile silt (2).

8. Staircase according to one of claims 1 to 6, characterized in that each step (3) has a projecting finger (22) extending horizontally spreading towards the fixed stringer (1), which has a light (13) in which the finger (22) of the step (3) penetrates during deployment of the staircase to end up against the bottom of the light (13) at the end of deployment.

9. Staircase according to one of claims 1 to 8, characterized in that the lower end (9) of the movable stringer (2) is equipped with means of rolling or sliding on the floor.

10. Staircase according to one of claims 1 to 9, characterized in that it comprises means (10) for locking or hooking in position of use, for example means of attachment and / or blocking of at least one of the upper and lower ends of the movable stringer in the deployed position.

11. Staircase according to one of claims 1 to 10, characterized in that a handrail (23) guided in rotation around its axis is mounted on a fixed support (8) along the fixed stringer and has handles (25) rotation control and levers (24) acting on steps (3) for the start of the deployment of the staircase.

12. Staircase according to one of claims 1 to 11, characterized in that it comprises a guardrail (20) secured to a step nose (4) mounted rotating on the upper ends of the fixed stringer (1) and the stringer mobile (2) and which opens when the staircase is deployed in position of use and closes when the staircase is folded down onto the fixed stringer, the guardrail (20) allowing the staircase to be deployed and folded down from from the top.