US20200237100A1

US20200237100A1 - Self-adjustable backrest device

Info

Publication number: US20200237100A1
Application number: US16/851,919
Authority: US
Inventors: Rafael BLASCO ANDREU
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-11-23
Filing date: 2020-04-17
Publication date: 2020-07-30

Abstract

The self-adjustable backrest device supplements a seat surface such that said seat surface is a previously existing one and what is covered by the object of this invention adds a backrest or improves the existing one, for which purpose it comprises a mobile plate on which the user rests, wherein said plate swivels on a horizontal shaft that passes through a first set of hubs connected to the plate, that shaft being associated with a second set of hubs connected to a support that may be the backrest itself of the chair or easy chair on which the self-adjustable backrest is going to be used, in which case it will be referred to as pre-existing backrest, or it may be a fixed backrest which forms part of the device, in which case it will be referred to as backrest of the device. The device may include fixing elements to prevent its movement, such as legs, pegs, or a flap.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part application that claims priority from and the benefit of U.S. application Ser. No. 15/778,316 filed on May 23, 2018, which is a 371 of International PCT/ES2016/07083 filed on Nov. 21, 2016, which claims priority from and the benefit of Spanish Application Nos. U201631384 filed on Nov. 21, 2016 and U201531301 filed on Nov. 23, 2015.
The foregoing applications, and all documents cited therein or during their prosecution (“appln cited documents”) and all documents cited or referenced in the appln cited documents, and all documents cited or referenced herein (“herein cited documents”), and all documents cited or referenced in herein cited documents, together with any manufacturer's instructions, descriptions, product specifications, and product sheets for any products mentioned herein or in any document incorporated by reference herein, are hereby incorporated herein by reference, and may be employed in the practice of the invention. More specifically, all referenced documents are incorporated by reference to the same extent as if each individual document was specifically and individually indicated to be incorporated by reference.

TECHNICAL FIELD

The present invention relates to a self-adjustable backrest device, which has an automatic means of position adaptation for the user's comfort. It is applicable to any type of chairs seats that have in its back at least a support preferably comprising vertical bars as for example wheel chairs or some geriatric chairs.

STATE OF THE ART

For the manufacture of vehicle, office or of any other type of seats, more or less complex systems are applied so the backrest adapts to the user's position.
Thus, for example, patent ES2118081T3 refers to a chair comprising a seat and backrest connected to each other, characterized in that the backrest presents certain movement in being associated with two horizontal shafts, one on which it swivels, and another that limits its movement.
Patent US2005035636A1 discloses a chair of the type comprising a seat and backrest connected to each other, being self-adjustable, characterized by comprising a backrest formed by back-support plate, supported by a horizontal shaft joint provided on a support, such joint being at a certain distance from the base of the backrest, preferably in an area at an average height of the backrest, and has a rotation spring cushioned and limited by a rotation limit system, and when the plate is in resting position, it is in an approximately vertical position. The plate, the support and the joint are included in a semi-rigid casing.
None of the cited patents provides lumbar support.
Patent WO9427472A1 describes a chair comprising a seat and backrest connected to each other characterized by comprising a backrest/back support plate, supported by a horizontal shaft joint.
Patent ES2255466A1 refers to a self-adjustable chair characterized in that it comprises a continuous single piece that serves as backrest and seat and is supported by a joint.
Patent U.S. Pat. No. 6,435,615B1 discloses a chair comprising a seat and backrest connected to each other, characterized in that the backrest is supported by a horizontal shaft joint.
Patent DE20113075U1 refers to a chair, which comprises seat and backrest, characterized in that the backrest comprises an arm with two shafts, a lower one that associates it with the seat and another upper one that regulates the position of the plate on which the user rests.
None of these patents refer to an independent backrest that can be coupled to different chairs.
Patent US2005168044A1 describes a seat backrest that has a lower extensions suitable to be pushed into the ground, such as at the beach, and serves as backrest for users sitting on the ground.
Patent WO0117398A1 discloses a self-adjustable seat that is supported on the ground with an adaptation system not comprising a horizontal shaft.
None of the patents cited refer to an independent backrest, suitable to be installed in any type of chair, easy chair, armchair, or even on the floor itself that protects the lumbar area regardless of the posture adopted by the user and which lifts the buttocks relaxing the pressure thereon.

BRIEF EXPLANATION OF THE INVENTION

The invention relates to a self-adjustable backrest device, which protects the lumbar area and relaxes the pressure on the buttocks.
The backrest is self-adjustable, which means that it needs no control or command.
The device referred to supplements a seat surface such that the seat surface exists previously and what is covered by the object of this invention is that it adds a backrest.
The self-adjustable backrest assembly comprises a mobile plate on which the user rests, wherein said plate swivels on a horizontal shaft that passes through a first set of hubs connected to the plate, that shaft being associated with a second set of hubs connected to a support that preferably comprises two vertical bars at its sides and accessory elements to removably fix the second set of hubs to that support
The second set of hubs is adjustable in height and thus, height variation of the set of hubs will vary the height at which the plate is located and swivels.
Hub refers herein to any element that serves as support to the shaft allowing its rotation.
The mobile plate may have different dimensions and it can comprise more than one element. he plate has an initial position, in the absence of forces applied by the user or at his or her will, and a balancing run that can be limited by a maximum position and a minimum position.
The ideal initial or resting position is preferably close to the vertical line although that can vary depending on the angle of the support. This resting position is obtained thanks to the action of a rotation spring in the resting position of which the mobile plate is in an approximately vertical position where said rotation spring can be cushioned for user comfort.
While not being used, the mobile plate is forced into the resting position by the rotation spring, which is capable of overcoming the weight of the plate and bringing it to the initial position and holding it in that position, but allowing it to yield under the pressure exerted by the user when sitting down without the user perceiving an ejection force.
Optionally, the run of the plate can have a stop, to limit the movement of the mobile plate.
The assembly comprising the plate, the first and second set of hubs, the shaft and the support is suitable to be associated with a chair or may be the support pre-exists as a part of the chair, for example in the case of a wheel chair or some geriatric chairs.
Once the self-adjustable backrest device has been installed, the user will sit on a seat surface, that is approximately horizontal and pre-existing, and will support the back on the self-adjustable backrest device.
Preferably, the height of the shaft will be adjustable and will be arranged at between 12 and 33 cm above the user's seat surface, and preferably between 18 and 27 cm.
The seat device may have armrests or any other element without altering the nature of the invention. Also, the plate may have a curvature, cushioning, flexibility, rigidity, or any other measure to increase user comfort.
Lastly, the material will be wood, plywood, plastic, metal, fabric, wicker, or any other.
The plate may be separated from the shaft to facilitate the tasks of cleaning, repair, or adjustment, among others.

DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention, the following figures are included.

FIG. 1 shows the invention and shows also a part of a human body. The chair where the device is used has two side bars (one of them is shown) and the backrest claimed is fixed to the support, in this case a pair of bars one of them is shown. In FIG. 1 is shown one of the bars (5), the mobile plate (1), the second set of hubs (4) fixed to the support, in this case two bars, a fixing part (9), the rotation spring (8) The seat surface (10), in this case a chair, is also shown. It is also shown a stop (11) that limits the movement of the plate

FIG. 2 shows the bar (5) the mobile plate (1), the first set of hubs (2), the shaft (3), the second set of hubs (4) and the rotation spring (8) in this case shown separately exploded from the shaft. It is also shown in FIG. 2 the fixing zone (9) in this case fixed to the bar (5).

FIG. 3 shows, from above, the mobile plate (1), the first set of hubs (2) fixed to the mobile plate, the shaft (3), the second set of hubs (4), the rotation spring (8) connected to the second set of hubs, the fixing zone (9) suitable for fixing to the bar, not shown in this figure.

EMBODIMENTS OF THE INVENTION

Briefly described hereunder is an embodiment of the invention, by way of example and without limiting the scope thereof.
The self-adjustable backrest that supplements a seat surface.
A mobile plate (1) having a sufficient size to cover the user's back from the coccyx to the area of the shoulder blades.
A horizontal shaft (3) on which the aforementioned mobile plate swivels, the said shaft being supported by a first set of hubs (2) connected to the mobile plate and a second set of hubs (4) connected to the support, in this case two bars (5), beside the mobile plate so that the mobile plate is between those two bars.
A rotation spring (8) that is connected to the second set of hubs engages the shaft so that it keeps the mobile plate (1) in an approximately vertical position when it is in a resting position, i.e., when there is no external force acting thereupon.
The first set of hubs (2) is connected to the mobile plate. The shaft (3) is also associated with the second set of hubs (4) that are connected to the fixing zone (9) suitable for removably fixing to a support.
The second set of hubs is height-adjustable, and, by varying its height, the height of the plate and the shaft are modified in relation to the seat surface (10).
The shaft on which the plate swivels is located at a height of 23 cm, the normal height being between 12 and 33 cm from the seat surface and, preferably between 18 and 27 cm
The action of the first and second set of hubs, and the horizontal shaft associating them, allows the mobile plate to swivel such that the greater the force exerted by the user on the upper part of the mobile plate, the greater the action on the lumbar area, reducing the pressure on the buttocks being lifted.
A stop (11) limits the movement of the mobile plate (1).

Claims

1. A self-adjustable backrest device to supplement a seat surface, the backrest device comprising: a mobile plate (1), a first set of hubs (2) connected to the mobile plate, a second set of hubs (4) removably connected to a support (9), and a horizontal shaft (3) connected to the first set of hubs, supported by the second set of hubs and engaging a rotation spring (8) so that the mobile plate is pivotable with respect to the second set of hubs, wherein the horizontal shaft is disposed at a distance from the seat surface (10) of between 12 and 33 cm.

2. The self-adjustable backrest device according to claim 1, wherein the rotation spring, preferably cushioned, is disposed in a resting position where the mobile plate (1) is disposed in an approximately vertical position.

3. The self-adjustable backrest device according to claim 1, further comprising a stop (11) for limiting the movement of the mobile plate.

4. The self-adjustable backrest device according to claim 1, wherein the second set of hubs is adjustable in height along the support.

5. The self-adjustable backrest device according to claim 1, wherein the mobile plate includes more than one element.

6. The self-adjustable backrest device according to claim 1, wherein the distance from the seat surface is between 18 and 27 cm.