This application claims benefit of Italian patent application number TO2014A000121, filed Feb. 14, 2014, which is herein incorporated by reference.
1. Field of the Invention
The present invention relates to a chair with a seat and backrest movable in a synchronized way.
More precisely, the invention relates to a chair comprising a base structure, a backrest connected in a pivoting manner to the base structure and capable of being inclined backwards under a backward thrust applied by the user and a seat movable relative to the base structure in a manner synchronized with the inclination movement of the backrest.
2. Description of Prior Art
In the prior art, many solutions are known of chairs equipped with a synchronized movement of the seat and backrest.
Generally, the known solutions comprise lever mechanisms, which connect the backrest to the seat in an articulated manner, so that a backward pivoting movement of the backrest corresponds to a forward movement of the seat. The known mechanisms are generally also provided with elastic elements for elastically recalling the backrest and the seat into a resting position.
The mechanisms for the synchronized movement of the seat and the backrest are usually complex and expensive and involve a considerable increase in the cost of the chair.
The present invention aims to provide a chair with a seat and backrest movable in a synchronized manner that is simple, economical and formed by a reduced number of components.
According to the present invention, this object is achieved by a chair comprising:
The claims form an integral part of the disclosure given in relation to the invention.
The present invention will now be described in detail with reference to the attached drawings, given purely by way of non-limiting example, in which:
With reference to the Figures, numeral 10 indicates a chair according to the present invention. The chair 10 comprises a base structure 12 carrying a seat 14 and a backrest 16. The base structure 12 comprises two lateral uprights 18 located on opposite sides relative to the seat 14 and extending upwardly relative to the seat 14. In the illustrated example, the lateral uprights 18 are formed in an integral manner with the opposite ends of a cross-member 20. The cross-member 20 has a central area that extends in the transverse direction below the seat 14 and two lateral areas bent upwards, which terminate at the lateral uprights 18. The cross-member 20 is preferably formed of metallic material, for example, aluminum alloy or the like. The cross-member 20 is mounted at the upper end of a height-adjustable central column 22, of a known type in the field of office chairs. In a known manner, the central column 22 carries the cross-member 20 in a rotatable manner about a vertical axis, and is fixed to a plurality of arms 24 carrying respective pivoting wheels 26 at their outer ends.
With reference to
The backrest 16 comprises two connecting portions 36 fixed to respective lateral uprights 18 of the base structure 12. In the illustrated embodiment, the connecting portions 36 are hollow and receive respective lateral uprights 18 therein with shape coupling. Transverse pins 40 may be provided, inserted through aligned holes of the connecting portions 36 and of the lateral uprights 18 to prevent the connecting portions 36 becoming extracted from the lateral uprights 18.
The connecting portions 36 are connected to the support panel 28 by means of respective hinge portions 38. The hinge portions 38 are designed to allow an oscillation of the support panel 28 relative to the connecting portions 36 about a horizontal transverse axis A. According to a preferred embodiment, the hinge portions 38 and the connecting portions 36 are formed in one piece with the support panel 28. Preferably, the hinge portions 38 and the connecting portions 36 form downward extensions of the side edges 30 of the support panel 28. The hinge portions 38 are formed by two sections of flexible and elastically deformable plastic material, which define two localized flexion areas aligned on the axis A. When the hinge portions 38 are bent with respect to an undeformed position, the intrinsic elasticity of the plastic material produces an elastic force which tends to bring the hinge portions 38 back to their undeformed position.
The seat 14 is connected to the base structure 12 by means of at least one guide, which allows a movement of the seat 14 relative to the base structure 12 in a longitudinal direction indicated by the double arrow B. The direction B, along which the seat 14 is movable, is preferably straight and horizontal.
With reference to
With reference to
With reference to
Screws 70 engage respective threaded holes of the vertical pins 58. The screws 70 are associated with respective washers 72 which rest on the upper edges of the respective slots 68. The screws 70 secure the seat panel 50 to the supports 44 in the vertical direction without impeding the freedom of movement of the seat 14 in the direction B.
The backrest 16 and the seat 14 are connected together by means of at least one elastic connecting element 74, configured to move the seat 14 along the longitudinal direction B as a result of the oscillation of the backrest about the axis A. In the example illustrated, two elastic connecting elements 74 are provided, laterally located in the vicinity of the respective connecting elements 36.
Each elastic connecting element 74 is formed of a strip of flexible and elastically deformable material. Each elastic connecting element 74 has an arc profile with an upper end fixed to the lower edge 32 of the support panel 28 and a lower end fixed to the seat panel 50. According to a preferred embodiment, the elastic connecting elements 74 are formed in a single piece with the support panel 28 and with the seat panel 50. Alternatively, the elastic connecting elements 74 can be separate elements fixed to the support panel 28 and to the seat panel 50 by means of any known fastening system. The elastic elements 74 could also be formed in one piece with the seat panel 50 and be fixed to the support panel 28 or, vice versa, could be in one piece with the support panel 28 and be fixed to the seat panel 50. A single elastic connecting element may also be provided positioned in a central position of the support panel 28 and the seat panel 50.
In resting conditions, that is, without a backward thrust applied to the backrest 16, the backrest 16 and the seat 14 are in the position illustrated in
The end-stroke device, which limits the forward stroke of the seat 14, also limits the backward inclination of the backrest panel 28 given that the backrest 16 is connected to the seat 14 by means of elastic connecting elements 74.
When the backward thrust on the backrest 16 ceases, the hinge portions 38 and the elastic connecting elements 74 return to their undeformed configuration and carry the backrest 16 back into the upright position and the seat 14 into the retracted position.
The movements of the seat 16 and the backrest 14 are synchronized with each other. The amplitude of these movements is designed so as to provide optimum comfort. The synchronized movements of the seat and the backrest are obtained exploiting only the elastic deformation of the materials constituting the hinge portions 38 and the elastic connecting elements 74. The torque that opposes the backward flexion of the backrest 16 is given by the sum of the elastic return torques of the hinge portions 38 and of the elastic connecting elements 74. One of the main advantages of the present invention is that articulated mechanisms are not required to provide the synchronized movement of the seat and the backrest, nor are additional elastic elements required to provide the elastic return torque of the backrest.
Of course, without prejudice to the principle of the invention, the details of construction and the embodiments may be varied widely with respect to that described and illustrated, without departing from the scope of the invention as defined by the following claims.
Number | Date | Country | Kind |
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TO2014A0121 | Feb 2014 | IT | national |
Number | Name | Date | Kind |
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4391453 | Glaser | Jul 1983 | A |
4962962 | Machate et al. | Oct 1990 | A |
5486035 | Koepke | Jan 1996 | A |
8777312 | Diffrient | Jul 2014 | B2 |
20080169693 | Becker | Jul 2008 | A1 |
20120146377 | Diffrient | Jun 2012 | A1 |
Number | Date | Country |
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1057431 | Dec 2000 | EP |
1785070 | May 2007 | EP |
Entry |
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Italian Search Report and Written Opinion dated Jul. 22, 2014 for Application No. TO2014A000121. |
Number | Date | Country | |
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20150223605 A1 | Aug 2015 | US |