ADJUSTABLE CHAIR

Abstract

A piece of furniture comprises a seat, a backrest and a base. At least the seat and the base are movably coupled for reversible relative adjustment in a direction from a first configuration for sitting upright to a second configuration for sitting reclined. One or more support surfaces and a lever are operably coupled to support the seat on the base. The lever rotates about an axis transverse to the seating direction and moves being coupled with the one or more support surfaces at a first support portion defining first lever arm about the axis and a second, different, support portion defining a second, different, lever arm about the axis. The one or more support surfaces define a curved, noncircular path about the axis, such that relative displacement of the support surface and the axis in the seating direction is associated with rotation of the lever about the axis.

Claims

1. A piece of sitting furniture, in particular a reclining chair, in particular an office chair, comprising a seat, a backrest and a base; wherein at least the seat and the base are movably coupled for reversible relative adjustment in a seating direction from a first configuration for sitting in an upright posture to a second configuration for sitting in a reclined posture, wherein the piece of sitting furniture comprises one or more support surfaces and a lever operably coupled to support the seat on the base in at least the first and second configurations; wherein the lever is rotary about a lever axis transverse to the seating direction and movably and operably coupled with the one or more support surfaces at a first support portion defining a first lever arm about the lever axis and a second, different, support portion defining a second, different, lever arm about the lever axis, and the one or more support surfaces define a curved path that is noncircular about the lever axis, such that relative displacement of the support surface and the lever axis in the seating direction is associated with rotation of the lever about the lever axis.

2. The piece of sitting furniture according to claim 1, wherein the lever comprises one or more lever support surfaces defining a curved lever path matching the curved path for supporting the one or more support surfaces along the curved path; and wherein the one or more support surfaces form a substantially continuous surface along the curved path from and including the first support portion to and including the second support portion, and/or wherein the one or more lever support surfaces form a substantially continuous surface along the curved lever path from the first support portion to the second support portion.

3. The piece of sitting furniture according to claim 1, wherein the one or more lever support surfaces engage the one or more support surfaces.

4. The piece of sitting furniture according to claim 1, wherein the curved path is circular.

5. The piece of sitting furniture according to claim 1, wherein at least one of the lever axis is fixed with respect to one of the base and the seat, and the one or more support surfaces are fixed with respect to the other one of the base and the seat.

6. The piece of sitting furniture according to claim 1, wherein the seat and/or the backrest comprise a self-supporting shell and/or wherein the seat and/or the backrest comprise one or more felt layers.

7. The piece of sitting furniture according to claim 1, wherein the backrest is rotary coupled with the base about a backrest axis; and/or wherein the seat and the backrest are movably coupled for reversible combined motion from the first configuration into the second configuration.

8. The piece of sitting furniture according to claim 7, wherein the seat and the backrest are movably coupled for reversible combined motion from the first configuration into the second configuration by reversibly deformable couplings and/or rotary couplings defining non-parallel axes of rotation.

9. The piece of sitting furniture according to claim 1, wherein the base comprises a frame; and wherein the frame supports the backrest on laterally opposite sides, and/or wherein the frame and backrest are rotary coupled on laterally opposite sides.

10. The piece of sitting furniture according to claim 1, wherein at least part of the base and/or the backrest is at least partially resilient, allowing sideways flexion and/or torsion about a vertical axis of rotation of at least part of the seat and/or backrest.

11. The piece of sitting furniture according to claim 1, wherein at least part of the seat and at least part of the base are movably coupled for reversible relative rotation about a vertical axis of rotation.

12. The piece of sitting furniture according to claim 1, wherein one or more support surfaces and the lever are operably coupled to support the seat on the base in at least two configurations differing with respect to a relative rotation about an axis generally perpendicular to the lever axis.

13. The piece of sitting furniture according to claim 12, wherein at least part of the lever defines a curved lever support surface being curved in a direction parallel to the axis generally perpendicular to the lever axis and to the lever axis in a plane spanned by both these axes.

14. The piece of sitting furniture according to claim 1, being foldable, the seat being reversibly adjustable to a relatively vertical orientation.

15. The piece of sitting furniture according to claim 1, wherein at least part of the base is provided with a vertical adjustment mechanism for vertically adjusting at least part of the seat with respect to the base; and/or wherein the base comprises one or more wheels; and/or wherein the piece of sitting furniture comprises arm rests.

16. The piece of sitting furniture according to claim 14, wherein the seat is stable in the relatively vertical orientation and/or the seat is reversibly fixable in the relatively vertical orientation so as to maintain the orientation.

17. The piece of sitting furniture according to claim 13, wherein the one or more support surfaces define a curved support surface being curved a direction parallel to the lever axis.

18. The piece of sitting furniture according to claim 8, wherein the seat and the backrest are rotary coupled for reversible combined motion from the first configuration into the second configuration.

19. The piece of sitting furniture according to claim 8, wherein the seat and the backrest are movably coupled for reversible combined motion from the first configuration into the second configuration by reversibly deformable couplings and/or rotary couplings on laterally opposite sides of the seat and backrest, respectively defining non-parallel axes of rotation.

20. The piece of sitting furniture according to claim 5, wherein the lever axis is fixed with respect to the base, and the one or more support surfaces are fixed with respect to the seat.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The above-described aspects will hereafter be more explained with further details and benefits with reference to the drawings showing a number of embodiments by way of example.

[0050] FIG. 1 is a perspective view of a reclining chair as provided herein;

[0051] FIGS. 2, 3, and 4 are a partial exploded view of the chair in two viewing directions;

[0052] FIGS. 5A and 5B are a side view and a cross section view in a vertical front-back plane, respectively, of the chair in a first configuration;

[0053] FIGS. 6A and 6B are views as in FIGS. 5A, 5B of the chair in an intermediate configuration;

[0054] FIGS. 7A and 7B are views as in FIGS. 5A-5B and 6A-6B of the chair in a second configuration;

[0055] FIG. 8 is a cross section view in a vertical transverse plane, perpendicular to that of FIGS. 5B, 6B, 7B;

[0056] FIG. 9 is a side view of the chair of FIG. 1 in a folded configuration;

[0057] FIG. 10 shows another embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

[0058] It is noted that the drawings are schematic, not necessarily to scale and that details that are not required for understanding the present invention may have been omitted. The terms “upward”, “downward”, “below”, “above”, and the like relate to the embodiments as oriented in the drawings, unless otherwise specified. Further, elements that are at least substantially identical or that perform an at least substantially identical function are denoted by the same numeral, where helpful individualised with alphabetic suffixes; between different embodiments the reference numerals differ by hundreds.

[0059] FIG. 1 is a perspective view of a reclining chair 1 as provided herein in a first configuration. FIGS. 2-4 are partial exploded views of the chair in different viewing directions. FIGS. 5A, 6A, 7A and 5B, 6B, 7B are side views and, respectively, cross section views in a vertical front-back plane of the chair of FIG. 1 in different configurations. FIG. 8 is a frontal cross section view and FIG. 9 shows the chair in yet another configuration.

[0060] The chair 1 shown in FIGS. 1-9 is formed as an office chair but it will be evident to the reader that the functionality of the chair may be beneficial for any type of sitting furniture. The chair comprises a seat 2, a backrest 4 and a base 6 supporting the seat 2 and the backrest 4. The base 6 comprises a frame 8, which here as an option is largely U-shaped, a seat support 10, which here as an option is integrated in the frame 8, and a stand 12.

[0061] For reference the following sides may be identified from a normal users' sitting perspective: front F, back B, left L, right R, up U and down D. The chair 1 provides a seating direction in the front-back direction (F/B).

[0062] The stand 12 shown in FIGS. 1-9 is of exemplary shape only and in embodiments the stand may be of any design and may e.g. comprise a pedestal (not shown) of any suitable type, e.g. a disc and/or a ring and/or or a number of radial legs which may be provided with wheels. The base 6 may, possibly included into the stand 12, comprise a vertical adjustment mechanism for vertically adjusting (up/down) at least the seat 2, preferably the frame 8 and any attached parts e.g. the seat 2 and the backrest 4, with respect to the stand 12, such as a gas pressure spring setup. Also or alternatively, (the stand 12 of) the base 6 may provide a rotary arrangement allowing at least part of the chair 1, e.g. the frame 8 and any attached parts e.g. the seat 2 and the backrest 4, to rotate about a vertical axis A12. The chair 1 may further comprise arm rests (not shown).

[0063] In the chair 1, the seat 2, the backrest 4 and (the frame 8 of) the base 6 are movably coupled for reversible relative adjustment in a seating direction from a first configuration 1 for sitting in an upright posture (FIGS. 1,5A, 5B) to a second configuration 11 for sitting in a reclined posture (FIGS. 7A, 7B) and in an intermediate configuration III (FIGS. 6A, 6B) providing an associated intermediate sitting postures in between. As will be discussed below, the shown embodiment may continuously accommodate any configuration between the first and second configurations I, II.

[0064] The chair 1 comprises a lever 14, which may also be referred to as “rocker” 14. The lever 14 is fixed to the base 6 at the protruding seat support 10 (see below) and rotary about a lever axis A14 transverse to the seating direction SD. Here, the rotary coupling is provided by a lever pivot 13 fitting a base recess 15, but an inverted coupling (base pivot and lever recess) or any other rotary coupling could be provided as well. Note that in other embodiments, not shown, the lever and base need not be fixed, and the lever axis may be movable with respect to the base, e.g. at least part of the lever rolling and/or translating in a front/back direction.

[0065] The lever 14 comprises a continuous lever support surface 16 and is provided with optional openings 18. In another embodiment, not shown, plural lever support surfaces could be provided. The lever comprises an opening 19 allowing passage of the seat support rotation 10 upon rotation of the lever 14 about the lever axis A14 (see below).

[0066] The lever support surface 16 is curved in a circumferential direction about the lever axis A14. In the shown embodiment, as options, the curvature has a circular shape and is arranged noncircular about the lever axis A14. The lever support surface 16 is also laterally curved, in a direction along the lever axis A14, turning upwards towards the left and right sides (L, R) (in the shown embodiment as options in an circular shape and left/right symmetric) so that the lever support surface 16 has a saddle shape, here being symmetric (FIGS. 2-4, 8).

[0067] The seat 2 is provided with a continuous support surface 20, here by means of an optional support member 22, and with optional protrusions 24. In another embodiment, plural support surfaces could be provided and/or the support surface(s) could be formed by (parts of) the seat without intervening support member 24.

[0068] The shape of the support surface 20 is curved in a circumferential direction about the lever axis A14. In the shown embodiment, as options, the curvature has a circular shape and is arranged noncircular about the lever axis A14. The support surface 20 is also laterally curved, in a direction along the lever axis A14, turning upwards towards the left and right sides (L, R) (in the shown embodiment as options in an circular shape and left/right symmetric) so that the support surface 20 has a saddle shape, here being symmetric (FIGS. 2-4, 8).

[0069] In the chair 1, the shapes of the lever support surface 16 and support surface 20 match and in assembled state (FIGS. 1, 4A-8, see also below) the lever support surface 16 and support surface 20 rest on each other and, in the first configuration, engage each other substantially throughout. Relative to the lever axis A14, in the first configuration, the lever 14 and support surface 20 define a front support portion 16F forward of the lever axis A14 and a rear support portion 16B rearward of the lever arm A14 together defining a curved shape (here having a circular shape but being arranged noncircular about the lever axis A14).

[0070] In assembled state of the chair 1, the protrusions 24 are accommodated in the openings 18 restricting relative movement of (the support member 22 of) the seat 2 and the lever 14 which may increase reliability and/or safety of the chair (see below).

[0071] In other embodiments, not shown, one or more elements may be placed between the support surface and the lever, e.g. a felt layer and/or one or more bearing layers.

[0072] In the shown embodiment, the seat 2 and the backrest 4 comprise a self-supporting shell, which may be formed by one or more felt layers and/or resilient plastic. The seat 2 and backrest 4 are resiliently flexible somewhat being shape-maintaining and supporting a sitting user but accommodating slight deformation under elevated pressure.

[0073] The backrest 4 is rotary coupled with the frame 8 of the base 6 with rotary backrest couplings 25 on laterally opposite sides so that the backrest is rotary relative to the base about a backrest axis A4 defined by the rotary backrest couplings 25. In other embodiments, a rotary coupling could be located elsewhere, e.g. in the middle of the backrest instead of on lateral sides as shown. A benefit of the locations of the rotary backrest couplings 25, being in front of a user contact surface of the backrest 4 in the shown embodiment is that the axis of rotation A4 may intersect the spine of a sitting user leaning against the backrest 4, this assists a natural sensation when tilting the backrest 4 about the backrest axis A4.

[0074] The seat 2 and the backrest 4 are reversibly movably coupled with rotary couplings 26 on laterally (L/R) opposite sides of the seat 2 and backrest 4, respectively, each having an axis of rotation A26. The axes of rotation A26 of the respective rotary couplings 26 are nonparallel and aim inward-upward with respect to a sitting user's position. Upon deformation of the seat 2 and backrest 4 (see below) each axis 26 may become reoriented (in particular, turning to a parallel orientation relative to each other) about a respective centre of reorientation rotation.

[0075] Referring now to FIGS. 5A-5B, 6A-6B, 7A-7B it may be seen that the backrest 4 may be rotated with respect to (the frame 8 of) the base 6 about the backrest axis A4 from the first configuration 1 (FIGS. 5A-5B) to the second configuration II (FIGS. 7A-7B) via an intermediate configuration III (FIGS. 6A-6B) so that an upper part of the backrest 4 moves backward (B direction) and a lower part of the backrest 4 moves forward (F direction). At the same time, since the seat 2 and the backrest 4 are movably coupled and the seat 2 is movably coupled with the lever 14 and the base 6, the seat 2 moves forward (F) relative to the base 6 and therefore relative to the lever axis 14. By the operable coupling of their respective lever support surface 16 and support surface 20, the seat support member 22 and the lever 14 cooperate and perform a combined motion about the lever axis A14. In the combined motion, the lever 14 is urged by a combination of forward and downward forces from the seat and possibly any user sitting on the seat, along a curved path defined by the combination of (lever) support surfaces 16 and 20, into rotation from a first orientation in the first configuration 1 (FIGS. 5A-5B) via an intermediate orientation (FIGS. 6A-6B) to a second orientation in the second configuration 11 (FIGS. 7A-7B). By the rotation, a front portion of the lever 14 rises and raises the front support portion 16F along the curved path defined by the respective cooperating supporting surfaces 16, of the lever 14 and support member 22. Thus the seat 2 is raised, staying supported on (the seat support 10 of) the base 6 via the lever 14 and the respective cooperating supporting surfaces 16, 20 of the lever 14 and support member 22. Therefore, together with the forward movement of the seat 2 relative to the base 6, the seat 2 is raised by a change from the first configuration 1 to the second configuration II. In addition, due to the rotary coupling between the seat 2 and backrest 4, the angle between the seat 2 and the backrest 4 is increased, opening up the seating angle and reducing or preventing raising at least the front edge of the seat so as not to lift the knees of a sitting user. In combination, an effect of a rotation of the seat 2 and backrest 4 about the hip joint of a sitting user is provided. Also at the same time, due the nonparallel axes of rotation A26 of the rotary couplings 26 will tend to align so that the seat 2 and backrest 4 deform slightly inward therewith increasing curvature of the seat 2 and backrest 4 thus increasing lateral confinement and sense of security of a sitting user.

[0076] The change from first to second configuration may be reversed by (attempt of) assuming a straight sitting up posture.

[0077] In other words, in the chair 1, the seat 2 is rotary coupled to the backrest 4 and the backrest 4 is rotary coupled to the base 6 about an axis of rotation A4. The seat 2 is suspended from the backrest 4 and movably supported on the rocker 14, providing a fulcrum to the seat 2. The rocker 14 is rotary coupled to the base 6 about an axis of rotation A14 and has a noncircular shape about its axis of rotation A14. Thus, upon rotation of the lever 14 about its axis of rotation A14, the position of the fulcrum changes relative to the base 6 and/or the seat 2. Rotation of the backrest 4 relative to the base 6 about the backrest axis A4 is associated with at least forward-backward translation of the seat 2 with respect to the base 6. The base 6, rocker 14, and seat 2 are movably coupled such that the translation of the seat 2 relative to the base 6 causes rotation of the rocker 14 about the axis of rotation A14 therewith causing a change in the position of the fulcrum along a curved path.

[0078] The upward arms of the frame 8 supporting the backrest couplings 25 are somewhat resiliently flexible, allowing sideways flexion and torsion of the frame 8 and backrest 4 about a vertical direction relative to the lower end of (the frame 8 of) the base 2, in particular the seat support 10. The flexion and/or torsion may be asymmetric with respect to the base 6 and in particular with respect to (an axis A12 of) the stand 12.

[0079] Since the support surface 20 and lever support surface 16 are operably coupled and shaped as described above, see FIG. 8, the seat is supported on the base by the lever a continuous range of configurations differing with respect to a relative rotation about an axis associated with the flexion and/or torsion which is generally perpendicular to the lever axis A14, both in the first and second configurations (I, II), and in between (Ill).

[0080] In the chair 1, the seat 2 (in particular the support member 22) and the lever 14 may be attached, e.g. by locking the protrusions 24 to the openings 18 (which then e.g. optionally may be though holes). However the seat may be separable from the base 6 and/or lever 14 to allow folding the chair 1 as shown in FIG. 9. Note that in another embodiment, not shown, the lever 14 may be attached to (the support member 22 of) the seat 2 and be detached from (the seat support 10 of) the base 2 as well. The folded configuration may be secured by appropriate means. E.g, a lock could be provided in one or both rotary couplings 26.

[0081] As may be seen in the Figures, at least part of the base 6 may comprise hollow members fortified with beams and/or ribs. This facilitates manufacturing by molding techniques.

[0082] FIG. 10 shows a chair 101 as another embodiment. Like chair 1, the chair 101 comprises a seat 102 and a backrest 104. An adjustment mechanism comprising a lever and a support structure as discussed above is not shown; the chair 101 is otherwise substantially equal to the chair 1 of FIGS. 1-9 so that only relevant differences are discussed below. In FIG. 10 stand 112 is shown provided with a number of radial legs 129 each provided with a swivel wheel 131. Different from chair 1 of FIGS. 1-9, chair 101 comprises arm rests 133. As an option the arm rests 133 are integrally formed with the frame 108. However, the frame 8, 108 may be formed as an assembly of different parts. As one or more options, the arm rests may be formed and/or positioned differently and/or they may be adjustable, e.g. being detachably connected and/or hinged mounted to the frame 108 and/or other portions.

[0083] Also, a handle 135 for manipulation of a height adjustment system (not shown) in the stand 12 is visible, as an option being at least partly integrated in the frame 6.

[0084] The frames 8, 108 of the chairs 1, 100 may be formed in the same manner as a shell with fortification ribs. Also or alternatively, at least part of the frame, the lever and/or the base may be formed by injection molding with gas bubble injection. This technique allows creation of comparably large at least partly hollow structures that may be bent and of which structural characteristics may be well predefined. In particular the frame 108 with integrated arm rests may therefore be manufactured comparably low-cost. Preferred material for gas bubble injection molding may comprise or be, at least substantially, a polyamide (e.g. Nylon). Note that other manufacturing techniques such as insert molding and/or overmolding may be used, providing a core material and/or-structure surrounded by another material and/or-structure.

[0085] The disclosure is not restricted to the above described embodiments which can be varied in a number of ways within the scope of the claims. For instance the seat and/or backrest may have different shapes and/or could comprise plural layers and/or stuffing. Various parts of the chair may be assemblable, disassemblable and/or reassemblable without tools e.g. by releasable snap connections facilitating manufacturing, repair and/or recycling. The chair may comprise a head support. The frame may be formed differently.

[0086] Elements and aspects discussed for or in relation with a particular embodiment may be suitably combined with elements and aspects of other embodiments, unless explicitly stated otherwise.