Safety device for folding metal "Bistro" type chairs, designed to keep the chair in the folded position.

Abstract

The invention relates to a one-piece plastic device for effectively holding a folding metal bistro chair in the folded position, facilitating storage and handling. The device comprises two ends: an open loop for attaching to the chair's crossbar, allowing free pivoting, and a hook for attaching to a seat slat to secure the chair. The device is easy to install without tools or modification to the chair's structure, adaptable to various similar chair models, and made of weather-resistant and UV-resistant material. A tab allows for easy removal of the device with a simple press. The assembly has dimensions adapted to the necessary ergonomics and robustness, and is manufactured using an injection molding process. Figure to be published for the abstract: Figure 3

Description

Title of the invention: Safety device for folding metal chair of the "Bistro" type, intended to keep the chair in the folded position. Technical field of the invention

[0001] The present invention relates to an accessory, hereinafter referred to as the device, designed for easy installation on folding chairs, more specifically of the 'bistro' type, operable with one hand, and allowing the chair to be held in the folded position when not in use. Technological background of the invention

[0002] Bistro-type folding chairs have the advantage of a simple construction, and folding them for transport or storage, whether upright or flat, is also very simple. These chairs consist of a three-part metal frame with: on one plane, the front legs and the backrest; on another, smaller plane, the rear legs at its lower end and, at the top, an axle allowing the front part of the seat to articulate; and the third plane containing the seat, the rear of which rests on one of the longitudinal metal rods positioned halfway up the front leg-backrest plane mentioned above. To fold these chairs, simply lift the rear of the seat, which will then slide up along the front leg-backrest plane. Attached to the part of the chair that forms the rear legs, the seat will bring these legs into alignment with the front leg-backrest plane.

[0003] This is where the drawback of these chairs lies: once folded, the chair can very easily unfold unintentionally. Firstly, when the chair is lifted, the seat tends to return to its open position on its own due to gravity. This can also occur when the chair is placed upright. Furthermore, if the user, holding the folded chair by the backrest, puts their feet on the ground, the pressure exerted or even the simple movement can also trigger the unfolding mechanism. Finally, when several chairs are lined up against each other upright, removing one can also cause the chair next to it to unfold.

[0004] In these different circumstances, the handling of chairs is often difficult, remains impractical and can even prove dangerous for the hands or legs of the user due to risks of pinching or shocks.

[0005] According to the author's research, there are currently two types of devices—plastic or metal—intended for use with these chairs. The first type aims to secure several chairs together when they are open. and placed side by side to ensure an orderly arrangement – ​​for example, for the audience at a performance. There are also supports designed for storing chairs: L-shaped or bracket-shaped, for wall mounting, they allow one or more chairs to be hung on them when folded, depending on their capacity. General description of the invention

[0006] The invention that is the subject of this patent application aims to prevent a folding bistro-type chair from opening on its own or through an unintentional action by the user. This device is intended to keep the chair in the folded position to facilitate safe handling and storage.

[0007] The invention is in the form of a single-piece plastic part, measuring between 40 mm and 50 mm in length, between 10 mm and 15 mm in width, between 20 and 30 mm in height, and with a body thickness of between 4 mm and 7 mm. It consists of two ends: one end is curved to form an open loop with an inner diameter of between 7.5 mm and 9 mm, while the opening measures between 5 and 6.5 mm, and the other end has an elbow-shaped hook with an opening angle of between 60° and 90°, a radius of curvature of between 1 mm and 3 mm, and a length at the elbow exit of 10 to 20 mm. A protrusion in the form of a beak, 8 to 15 mm long, surmounts the end with the open loop.

[0008] The curved, loop-shaped section is designed to clip onto the chair's mid-height transverse axis, the axis against which the seat rests when the chair is in the unfolded position. A small tab is located at the rear of this curved section to facilitate handling the device when removing it. Once attached to the transverse axis, the device can pivot freely around it and remain in place indefinitely without hindering the normal use of the chair, whether in the open or folded position.

[0009] When the chair is in the folded position, its seat, made of metal slats, rests against the axis on which the invention is installed. The other end of the device, forming an angle with an open hook, will hook onto the metal slat positioned opposite the chair's axis.

[0010] To use the device, the user folding the chair simply needs to hold the chair folded with one hand and, with their free hand, rotate the device on its axis to hook the metal blade located against the chair's axis. Once in place, the tension exerted by the seat—or, failing that, gravity—holds the device in position, preventing the chair from unfolding. The chair can then be lifted, placed upright on the floor, or moved without unfolding.

[0011] To disengage the device, the user holds the chair with one hand and, with the other, applies slight pressure to the lever of the invention. This has the effect of to release the hook from the seat blade, freeing the blade to allow it to move away from the chair frame and unfold. As mentioned previously, this action does not separate the device from the chair; it can remain in place for later use.

[0012] The device is designed to be installed and used without the need for any special tools, attaching directly to the existing structure of a bistro-style chair. Attachment is achieved by positioning the loop opening of the device against the chair's axis and applying pressure to clip the device onto its axis. Conversely, the device can be removed simply by detaching the loop-shaped portion from the chair's axis with a lateral rotation to the right or left.

[0013] The device is designed to adapt to different models of 'bistro' type folding chairs, thanks to its standardized design, and is compatible with chairs whose seats are made of metal slats. This does not affect the chair's dimensions or its storage position, allowing them to be stacked without difficulty.

[0014] The invention exhibits high robustness under stress. It resists the normal forces exerted by the user attempting to open the chair, such as pressure on the upper edge of the seat or when handling the chair while it is resting on its legs.

[0015] The preferred manufacturing material is plastic, due to its mechanical resistance as well as its resistance to weathering and UV radiation, ensuring prolonged outdoor use. Materials such as PMMA, polycarbonate, polypropylene, polystyrene, or bioplastics are being considered to ensure the durability and robustness of the device.

[0016] Depending on the type of plastic chosen, the accessory can be made by injection molding, in order to keep manufacturing costs as low as possible while ensuring wide distribution and adaptation to the outdoor furniture market.

[0017] This device, thanks to its simple and lightweight design, allows for quick installation and ensures that the chair is effectively held in the folded position, without requiring any major structural modification. It is designed to remain permanently in place on the chair, both when in use in the open position and when stored.

[0018] The invention is primarily intended for manufacturers of outdoor furniture, particularly for folding bistro-type chairs, but it can also be used in other environments where folding chairs need to be kept closed for storage or transport. It is also suitable for use after the chair has been purchased and is intended for all types of users: public places such as bars and restaurants as well as private individuals.

[0019] Description of a preferred embodiment of the invention

[0020] Device Description: The device is a single-piece plastic component, measuring between 40 mm and 50 mm in length, between 10 mm and 15 mm in width, between 4 mm and 7 mm in thickness, and between 20 mm and 30 mm in height. It consists of two distinct ends: a curved section forming an open loop with an inner diameter between 7.5 mm and 9 mm on one side, and on the other, an angled section with an opening angle between 60° and 90° and a radius of curvature between 1 mm and 3 mm. A protrusion in the shape of a beak, measuring 8 to 15 mm, is located at the rear of the curved section forming the open loop. The material is a weather-resistant and UV-resistant plastic, such as PMMA, polycarbonate, polypropylene, polystyrene, or bioplastic.

[0021] Device Installation: To install the device on the chair, the user must position the chair's mid-height crossbar against the opening of the loop-shaped section. The user then pulls upwards to insert the chair's crossbar into the loop of the device, thus clipping the device onto the chair's crossbar. This movement is performed without tools and with moderate effort, ensuring quick and easy installation. Once installed, the device can pivot freely around the crossbar, allowing the user to leave it in place indefinitely without interfering with the normal use of the chair.

[0022] Use of the device: When the user wishes to fold the chair, they fold it while holding the seat up with one hand. With their free hand, they rotate the device so that the open hook is positioned on the lower metal blade. The hook, having the appropriate opening angle, catches on the metal blade of the seat, thus locking the chair in the folded position. Once in place, the tension exerted by the chair seat, or failing that, gravity, holds the device in position and prevents the chair from unfolding unintentionally. The user can then move, transport, or store the folded chair without fear of it unfolding (for example, during vertical movement).

[0023] Disengaging the device: To release the chair, the user holds the chair with one hand and, with the other, operates the lever located at the rear of the device's loop. Slight pressure on the lever rotates the device, disengaging the hook from the metal blade of the seat. The lever is designed for easy manipulation, allowing the user to disengage the device with a simple thumb movement. Once the hook is released, the seat separates from the crossbar and the chair can be unfolded normally. The device remains in place, ready for future use.

[0024] Practical advantages: a. Quick and tool-free installation, making it easy to use for any type of user. b. Effectively maintains the chair in the folded position, reducing the risk of accidental unfolding. c. Compatibility with different brands and models of 'bistro' type chairs, without altering the ability to stack or store them. d. Simple and lightweight design, allowing for intuitive use and economical production.

[0025] Adaptability and robustness: The device is designed to be compatible with various models of 'bistro' type folding chairs, due to its standardized shape and its ability to adapt to chairs with a metal seat. The device is made of weather-resistant and UV-resistant plastic, which guarantees prolonged outdoor use without material degradation. Furthermore, it is designed to withstand the forces exerted by the user attempting to open the chair, such as pushing on the seat or manipulating the chair while it is resting on its legs.

[0026] Manufacturing process: The device is manufactured by injection molding, a process that ensures low-cost mass production while meeting the requirements for robustness and durability. This process ensures widespread distribution of the invention, allowing it to reach the outdoor furniture market, whether for manufacturers or individuals. Brief description of the figures

[0027] [Fig.1] presents the device as a whole with the three components besides the body (1) of the device: fixing loop on the axis of the chair (2), hook designed to catch the blade of the seat (3) and operating spoiler (4).

[0028] [Fig.2] presents the invention in its context of use with an unfolded chair on which the device is installed but unused.

[0029] [Fig.3] presents the invention in its context of use with a folded chair on which the device has been attached. List of reference signs

[0030] 1. Device 2. Fastening loop 3. Crochet 4. Spoiler

Claims

Demands

1. A device for holding a folding metal chair of the "Bistro" type in the folded position, consisting of a single elongated piece of resistant plastic, comprising a hook at each end, characterized in that: a. One end forms an open loop (2) designed to clip onto the transverse axis of the chair on which the seat of the chair rests in the unfolded position, b. the other end has an elbow-shaped hook (3) which, once the device is clipped onto the transverse axis of the chair, is designed to fit between two slats of the chair seat and then hook the lower slat by means of a simple rotation of the device around its axis, preventing the seat from moving away from the structure and thus locking the chair in the folded position, c. The device has a spoiler (4) located at the rear of the fastening loop (2), designed to allow the user to act on the device with a simple press of the thumb to rotate it and release the hook (3) when he / she wishes to unlock the device.

2. Device according to claim 1 characterized in that: - its length is between 40 mm and 50 mm, - its width between 10 mm and 15 mm - its height between 20 and 30 mm - its general thickness between 4 mm and 7 mm. and in that: a. The open loop (2) has an inner diameter between 7.5 mm and 9 mm so that, once clipped, it remains in place on the transverse axis of the chair while still being able to rotate freely around this axis. b. The elbow-shaped hook (3) has an opening angle between 60° and 90°, a radius of curvature between 1 mm and 3 mm, and an elbow exit length between 10 and 20 mm. c. The spoiler (4) consists of a projection of 8 to 15 mm at the rear of the open loop (2).

3. Device according to any one of claims 1 and 2, characterized in that the device has a one-piece body made entirely of weather-resistant and UV-resistant plastic, such as PMMA, polycarbonate, polypropylene, polystyrene or bioplastic, ensuring prolonged outdoor use and adequate robustness, as well as resistance to normal forces exerted by the user attempting to open the chair, such as pressure on the seat or handling while leaning on the ground.

4. Device according to any one of claims 1 to 3, characterized in that the device is manufactured by injection molding to ensure a low production cost, allowing for widespread distribution and adaptation to the outdoor furniture market.

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