DE202023100146U1 - Seating - Google Patents

Abstract

Seating furniture (2), in particular an office chair, with a seat (4) and a backrest (14) which has two vertical struts (16) which are spaced apart from one another and are covered with a covering (22), wherein the vertical struts (16) are more elastic in a first direction (28) compared to a second direction (26) perpendicular thereto, and wherein the two first directions (28) are directed in a longitudinal direction (13) of the seating furniture (2) and towards one another.

Description

The invention relates to a piece of seating furniture. The seating furniture is preferably an office chair.

A piece of seating furniture is generally understood to be a piece of furniture on which at least one user can sit. This basically includes chairs, office chairs (both swivel chairs and conference chairs) and armchairs (also known as lounge furniture). Such seating furniture usually has a seat and a backrest set at an angle to it, which the user can lean on.

For example, the backrest is completely rigid, so that robustness is increased. To increase comfort, however, a rigid support structure of the backrest is covered with foam, which means that the user is not injured when leaning on it. To ensure that the user is adequately supported, there is usually a mechanism or at least defined points of contact of a mechanism on the user's back, such as a lumbar support. This provides targeted support for the spine and/or back muscles. This means that the seating furniture can also be used over a longer period of time without causing fatigue.

If the foam is too soft, it is possible that the user will feel the mechanism with their back if they lean back relatively far, which will lead to a loss of comfort. If, on the other hand, the foam is too hard, the seat will not adapt to the shape of the user's back, and the user will not notice any difference to a completely rigid backrest. To remedy this, the mechanism is usually designed in such a way that the user's back is supported more when the load is greater. For this purpose, the mechanism has several joints, for example. However, such mechanisms are comparatively heavy, which increases the weight of the seat. It is also necessary to choose a foam with progressive damping properties, in particular with variable density or with zones made of different materials. This increases production costs.

The invention is based on the object of specifying a particularly suitable piece of seating furniture, wherein comfort is advantageously increased and/or weight is reduced.

According to the invention, this object is achieved by the features of claim 1. Advantageous further developments and embodiments are the subject of the subclaims.

The seating furniture has a seat that is suitable, in particular intended and set up, for a user to sit on. The seating furniture also has a backrest that is suitable, in particular intended and set up, for a user to lean his back on when sitting on the seat. For example, the backrest is rigidly attached to the seat or, particularly preferably, is pivotably mounted relative to it. The seating furniture preferably comprises a frame by means of which the seat and the backrest are stabilized relative to one another. The frame comprises, for example, one or more legs that serve to make contact with a floor/subsurface. Alternatively, the seating furniture has a base to which several castors are attached so that the seating furniture can be moved appropriately. The frame is suitably designed to be height-adjustable so that the distance of the seat from the floor/subsurface can be changed. The seating furniture, expediently the office chair, preferably comprises two armrests that serve to rest elbows when the user sits on the seating furniture.

In particular, the seating furniture is designed as an office chair. The office chair preferably has the possible frame, which in particular has a rotatable and height-adjustable chair column. The chair column is attached to the possible base, which has star-shaped cantilever arms, at the ends of which a roller is held. The office chair can thus be moved/repositioned along a surface. For example, the office chair comprises two armrests that are attached to the frame, the backrest and/or the seat. In an alternative, the seating furniture is, for example, an armchair or a sofa.

The backrest has two vertical struts which, at least in the intended state of the seating furniture, run essentially in the vertical direction and are inclined to the vertical direction by no more than 30° or 15°, for example. The two vertical struts are spaced apart from one another and provided with a covering. Consequently, the vertical struts do not lie against one another. Each of the vertical struts expediently forms a boundary of the backrest, in particular a lateral one. In summary, in particular the laterally opposite edges of the backrest are each formed by means of one of the vertical struts. The covering is preferably held by means of the vertical struts, and the shape of the backrest, in particular the external dimensions, preferably define the dimensions of the covering. Suitable The covering is usually stabilized by means of the vertical struts. In particular, the covering is at least partially flat. Due to the vertical struts, it is therefore not necessary to design the covering to be self-supporting and/or rigid, which is why the weight of the backrest is comparatively low.

The covering is used in particular for the user's back to lean against and is particularly suitable, intended and/or set up for this purpose. In other words, in the intended state, the user leans his back against the covering. In the intended state, the covering is expediently located at a rear end of the seat of the seating furniture and/or runs at least essentially vertically and is therefore only inclined to the vertical by a small angle, for example less than 20°, 10°, or 5°.

The vertical struts are elastic in a respective first direction compared to a respective second direction perpendicular thereto. The two directions run in particular in a common horizontal plane, and each of the vertical struts is assigned the corresponding directions that differ between the two vertical struts. It is thus possible to bend each of the vertical struts more easily in the first direction than in the second direction when force is applied to them. If a force is thus applied to the respective vertical strut in the first direction, it will be elastically bent more extensively than if the same force is applied to the same vertical strut in the respective second direction. For example, each of the vertical struts is designed to be essentially rigid in the respective second direction and/or essentially flexible in the first direction. For example, the construction of the vertical struts is such that this effect is achieved. Alternatively or in combination with this, such a design of the vertical struts is achieved by means of an appropriate choice of material and/or orientation of the material. In particular, the vertical struts are made of a metal or, for example, of a plastic, preferably a glass fiber or carbon fiber reinforced plastic.

The first directions of the two vertical struts and the second directions of the two vertical struts differ, and the two first directions are partly directed in a longitudinal direction of the seating furniture and partly towards each other. In other words, each of the first directions has a component that is directed towards the other vertical strut and another component that is directed in the longitudinal direction, i.e. in the direction of the seat and/or in the direction in which the user looks when sitting on the seat as intended. The second directions are preferably directed against the longitudinal direction and towards each other.

If a force is applied to the covering against the longitudinal direction, i.e. when the user leans on the covering, the covering is partially moved against the longitudinal direction. This leads to an elastic bending of the two vertical struts partially towards each other and therefore also in the longitudinal direction. This means that the backrest is not completely rigid, which increases comfort. The force applied to the user's back by the backrest increases the more the user leans on the backrest, so that a comparatively progressive spring characteristic is realized, which increases comfort. No comparatively complicated mechanics are required to achieve the increased comfort. This simplifies the design and reduces manufacturing costs. The weight of the seating is also reduced.

In summary, the more the user leans, the more the backrest applies a counterforce to the back, stabilizing the user's back. If the force acting on the covering is not directed entirely in the longitudinal direction, but also has a perpendicular, i.e. sideways, component, the vertical strut, which is in the lateral direction, will be bent more in the longitudinal direction. If the user looks in the opposite direction to the side and turns their upper body accordingly, the backrest essentially follows the user's movement. This further increases comfort. In summary, the backrest is designed in such a way that when the covering is subjected to a load, the vertical struts are moved lengthwise and towards each other against the longitudinal direction. In other words, the vertical struts are designed in such a way that when the covering is subjected to a load in the longitudinal direction, the vertical struts are not only bent lengthwise, but in particular against the longitudinal direction and towards each other. In summary, the backrest is expediently designed in such a way that the vertical struts are partially bent inwards towards each other when a force is applied against the longitudinal direction, whereby movement/bending of the vertical struts against the longitudinal direction, i.e. parallel to the force acting on the covering, is avoided.

For example, it is only possible to bend the vertical struts in the respective first direction, i.e. longitudinally and towards each other. Alternatively, elastic bending of the vertical struts in the opposite direction, i.e. lengthwise and away from each other, is also possible in principle, especially if the covering is not present. This simplifies the construction.

For example, the covering is at least partially rigid. However, it is particularly preferred that the covering is flexible and therefore not self-supporting. This reduces the weight of the covering. Also, when a force is applied to the covering, it is at least partially bent in accordance with the force applied, so that the introduction of force into the two vertical struts is improved. In other words, the mobility of the vertical struts is not affected by the covering. Also, when the covering is loaded, only a tensile force is applied to the vertical struts. For example, the covering is at least partially elastic. However, it is particularly preferred that the covering is inelastic. This means that essentially all of the force applied to the covering is introduced into the vertical struts, which increases effectiveness.

For example, the covering is made of a flexible fabric or at least includes this. For example, the fabric is provided with a cover such as leather, fabric or plastic. This increases robustness. In particular, there is padding between the cover and the fabric, so that comfort is further increased. However, the covering, and thus the fabric, is particularly preferably a flexible mesh. This provides ventilation on the one hand, which increases comfort. On the other hand, the weight of the backrest is reduced.

Preferably, the two vertical struts are not supported on one another between their half and at least one upper end. In other words, with the exception of the covering, there is no mechanical connection between the two vertical struts in the area between their half in the vertical direction and the upper end, so that movement of these relative to one another is not influenced. In this way, the two vertical struts are not prevented from moving towards one another, particularly when a force is applied to the covering. The two vertical struts are expediently not supported on one another at least in this area. In other words, the backrest is without cross struts at least in the area between the half and the upper end. In this way, weight and manufacturing costs are reduced. Functionality is also improved in this way. Preferably, the vertical struts are spaced apart from one another over their entire length and are not supported on one another, so that the entire seating furniture is without cross struts. Alternatively, at least one cross strut is present, although this is not located in the area between the half and the upper end. Preferably, any cross brace or at least a support of the vertical braces against each other is located vertically below a lordosis, so that the stabilization of the back occurs above this due to the deformation of the vertical braces. This increases comfort.

For example, the upper ends are supported on one another, in particular by means of an elastically designed cross brace. This means that movement of the vertical braces towards one another is not hindered when a force is applied to the covering, but is slightly influenced. In particular, this supports bending in the respective first direction. The cross brace increases the stability of the backrest in the unloaded state. This also makes it easier to move or transport the seating furniture. However, it is particularly preferred that the upper ends of the vertical braces are not supported on one another, so that they can be moved comparatively extensively in the first direction when the force acts on the covering in the longitudinal direction.

Particularly preferably, a respective lower end of the vertical struts is stabilized relative to one another, so that the vertical struts always have the same distance from one another, in particular regardless of the force acting on the covering. For this purpose, the two vertical struts are expediently connected to a common fastening strut, which suitably runs at least partially, for example completely, in a horizontal direction. In particular, the fastening strut is designed to be rigid or at least predominantly rigid.

For example, the fastening strut is located vertically above the seat. However, it is particularly preferred that the vertical struts are connected to the fastening strut below the seat. This means that the vertical struts can move vertically above the seat essentially without interference, i.e. in the area where the user's back is located. This means that a force is essentially exerted on the entire back due to the bending of the vertical struts, which increases comfort.

For example, the vertical struts are attached to the fastening strut using fastening means. However, it is particularly preferred that these are molded onto one another and thus form one piece with one another. This increases robustness on the one hand. On the other hand, production is simplified. For example, the fastening strut is arranged essentially horizontally, which simplifies construction and reduces space requirements. Alternatively, the fastening is bent, with the combination of the fastening strut and the two vertical struts preferably being essentially U-shaped.

For example, the vertical struts are always in the same position, regardless of whether the covering is present or not. However, the vertical struts are particularly preferably pre-tensioned. This means that they are elastically bent even when the covering is not under load, so that the covering is tensioned by means of this. Therefore, even if the covering is (minor) plastically deformed, for example due to aging effects, the functionality of the backrest is maintained, so that the service life of the seating furniture is increased. In this way, the vertical struts are only elastically deformed when the force acting on the covering exceeds a limit, so that the stabilization of the user's back is improved.

For example, the vertical struts are identical to one another or mirror images of one another. This simplifies the construction. For example, the cross section of the vertical struts in a horizontal plane is round or curved. For example, the cross section or at least the shape of the cross section depends on the height of the horizontal plane. However, the cross section of the vertical struts in the horizontal plane is particularly preferably rectangular, at least in sections, preferably along the complete course of the respective vertical strut. This simplifies the construction and manufacture of the vertical struts. For example, the cross section is a square. However, the respective cross section particularly preferably has an elongated extension in one direction. The direction is in particular parallel to the second direction. In other words, the rectangular cross section extends along the respective second direction. Thus, the shape of the vertical struts, with the material properties otherwise remaining unchanged, ensures that the vertical struts are more elastically deformable in the respective first direction. This simplifies the construction and manufacture.

For example, the vertical struts are hollow. This reduces the weight. However, the vertical struts are particularly preferably solid, which simplifies production. The vertical struts are expediently comparatively thin-walled and in particular leaf-shaped. In other words, the vertical struts are made in particular from a solid material, for example cut out, which is oriented parallel to the second direction. The thickness of the solid material extends in the first direction or is at least parallel to it. This simplifies the construction of the seating furniture, with the desired deformability for providing the functionality of the backrest already being achieved due to the use of the comparatively thin-walled solid material. This simplifies the weight and construction and reduces production costs.

Particularly preferably, the first two directions form an angle between 60° and 120° and essentially 90°, whereby, for example, a deviation of 10°, 5° or 0° is possible. In summary, the first two directions in particular each form an angle of 45° to the longitudinal direction. This prevents excessive bending of the vertical struts, while still allowing comparatively efficient application of force to the user's back.

For example, the cross-section of the vertical struts is constant in a horizontal plane along the entire length of each vertical strut. However, it is particularly preferred that the extension of the cross-section in the second direction shortens with increasing height of the plane in which the cross-section lies. In other words, the extension of the vertical struts in the respective second direction decreases with increasing height of the vertical struts, i.e. with increasing distance from the seat in the intended state. Thus, when a force is applied to the covering in this area, there is also a slight elastic deformation of the vertical struts in the second direction, which increases comfort. The support effect in the lower back area is improved.

• 1, 2 jeweils perspektivisch ein Sitzmöbel in Form eines Bürostuhl, mit einer Rückenlehne,
• 3 in einem horizontalen Schnitt durch die Rückenlehne das Sitzmöbel,
• 4 schematisch ausschnittsweise eine Abwandlung des Sitzmöbels,
• 5 in einem horizontalen Schnitt die Rückenlehne bei keiner Belastung,
• 6, 7 in einem horizontalen Schnitt die Rückenlehne bei einer Belastung, und
• 8 in einem horizontalen Schnitt die Rückenlehne bei einer geänderten Belastung.

In the following, embodiments of the invention are explained in more detail with reference to a drawing. In the drawing:

• 1 , 2 each perspective a seat in the form of an office chair, with a backrest,
• 3 in a horizontal section through the backrest of the seating furniture,
• 4 schematic detail of a modification of the seating furniture,
• 5 in a horizontal section the backrest under no load,
• 6 , 7 in a horizontal section the backrest under load, and
• 8th in a horizontal section the backrest under a changed load.

Corresponding parts are provided with the same reference numerals in all figures.

In 1 and in 2 In each case, a piece of seating furniture 2 in the form of an office chair is shown in perspective. The seating furniture 2 has a substantially horizontally aligned seat surface 4, which is located horizontally above a frame 6 and is connected to a height-adjustable chair column 8 of the frame 6. The chair column 8 is arranged substantially vertically, whereby its extension can be changed in the vertical direction. A base 10 of the frame 10 is arranged vertically below the chair column 8 and is attached to it. The base 10 has four extension arms 12, at the ends of which castors (not shown in detail) are held.

A backrest 14 is attached to the frame 10, namely to the upper end of the chair column 8 in the vertical direction, and is located behind the seat 4 in a longitudinal direction 13. The longitudinal direction 13 is the direction in which a user looks when he or she is sitting on the seat 4 as intended and leaning his or her back against the backrest 14. The backrest 14 has two vertical struts 16 that are spaced apart from one another and run essentially in the vertical direction. The lower end of each vertical strut 16 in the vertical direction is molded onto a common fastening strut 18. The fastening strut 18 is located vertically below the seat 4, and the two vertical struts 16 and the fastening strut 18 are made of a common material, namely a plastic, and are connected to one another. The two vertical struts 16 and the fastening strut 18 were made in an injection molding process in a common mold. Here, the combination of the vertical struts 16 and the fastening strut 18 is U-shaped in a rear view.

The vertical struts 16 are not supported on one another, with the exception of the fastening strut 18. Thus, the two vertical struts 16 are not supported on one another between their half and their respective upper end 20, and the two upper ends 20 of the vertical struts 16 are also not supported on one another. Thus, the seating furniture 2 or at least the backrest 14 is designed without cross struts.

The two vertical struts 16 are covered with a covering 22 which is connected to the front end of the vertical struts 16 in the longitudinal direction 13. The covering 22 consists of a net-like, flexible surface structure. The covering 22 is made of a plastic, whereby the material of the covering 22 is selected such that it is inelastic. Thus, a force acting on the covering 22 is introduced directly into the vertical struts 16 to which the covering 22 is attached. The covering 22 is folded over itself in the area of the upper ends 20, so that an edge 24 is formed which runs between the two ends 20.

In 3 the seating furniture 2 is shown in a plan view in a sectional view in a horizontal plane through the backrest 14. The two vertical struts 16 have a rectangular cross-section which extends along a respective second direction 26. The second directions 26 differ here and run counter to the longitudinal direction 13 and towards each other. The composite of the fastening strut 18 and the vertical struts 16 are cut from a common metal plate and bent accordingly, wherein the metal plate has a certain thickness. Alternatively, the three struts 16, 18 are produced in one piece using a common plastic injection molding process. The vertical struts 16 are arranged such that the thickness, i.e. the reduced extent, is perpendicular to the second direction 26 and parallel to a first direction 28. The first directions 28 assigned to the two vertical struts 16 differ here. The first directions 28 point partly in the longitudinal direction 13 and are directed towards each other. Here, the two first directions 28 are arranged at right angles to each other, so that each of the first directions 28 encloses an angle of 45° to the longitudinal direction 13.

The extension of the vertical struts 16 in the first direction 28 is essentially constant over the entire course. In contrast, the extension in the second direction 26 increases with decreasing distance from the seat surface 4. In other words, the extension of the cross section of each vertical strut 16 in the second direction 26 is shortened with increasing height of the plane of the cross section. In summary, each vertical strut 16 has a rectangular cross section in a horizontal plane that extends along the respective second direction 26. In this embodiment, the second direction 26 is constant for each vertical strut 16 along the entire course.

In 4 a modification of the seating furniture 2 is shown in detail, whereby the frame 10 is not shown. The backrest 14 is again present, which is located in the longitudinal direction 13 behind the seat 4. The vertical struts 16 have a rectangular cross-section in a horizontal plane, which extends along the respective second direction 26, which are directed opposite to the longitudinal direction 13 and towards each other. The first direction 28 assigned to the respective vertical strut 16, which is perpendicular to the respective second direction 26, is directed in the longitudinal direction 13 and towards the other vertical strut 16. Here too, the extent of the cross-section in the second direction 26 decreases with increasing height of the plane of the cross-section.

In a side view, the vertical struts 16 are essentially arched in this embodiment. The upper ends 20 of the vertical struts 16 are spaced apart from one another and are not supported on one another. They are only formed on the fastening strut 18 at their vertically lower end. The fastening strut 18 runs essentially in a horizontal plane and merges into one of the vertical struts 16 at each end via a respective bend 30. Here, too, the vertical struts 16 are covered by means of the covering 22, although this is not wrapped around itself in the area of the upper ends 20.

In the 5 -8 , the horizontal cross-section through the backrest 14 is shown in a simplified schematic form in each case, which applies to both designs of the seating furniture 2. Due to the cross-section of the vertical struts 16, these are essentially not elastically deformable in the respective second direction 26, whereas due to the reduced expansion in the respective first direction 28, they are elastically deformable in the first direction 28. In summary, the vertical struts 16 are more elastic in the first direction 28 than in the second direction 26. The vertical struts 16 are pre-tensioned by means of the covering 22. In other words, the covering 22 is tensioned between the vertical struts 16, with the vertical struts 16 already being at least slightly elastically deformed. In other words, if the covering 22 were not present, the vertical struts 16 would be bent opposite to the respective first direction 28.

In 5 the case is shown that no further force acts on the covering 22, so that it runs essentially flat between the two vertical struts 16.

In 6 shows how the backrest 14 behaves when a force acts on the covering 22 in the middle against the longitudinal direction 13, which is caused in particular by the user leaning their back against it. Due to the pliable design, the covering 22 is exploited in the middle between the vertical struts 16 against the longitudinal direction 13. The force acting on the covering 22 is transferred to the vertical struts 16, whereby only a tensile force can be transferred to the vertical struts 16 by means of the covering 22. Due to the bulging of the covering 22, a force acts on each of the vertical struts 16, which are directed towards one another and which leads to a reduction in the distance between the vertical struts 16. Due to the geometric design, the vertical struts 16 cannot be bent in the second direction 26, so that this can only be done by bending them in the respective first direction 28. Thus, the two vertical struts 16 are moved in the longitudinal direction 13 and towards each other, the more the covering 22 is exploited against the longitudinal direction 13, as in 7 shown in a representation of the two cross sections. The more the user leans against the backrest 14, the more the user's back is stabilized. In this example, the edge of the covering 22 approaches tangentially to the second direction 26 of the associated vertical strut 16.

In 8th is shown in a comparative illustration how the backrest 14 behaves when the force on the covering 22 acts completely against the longitudinal direction 13 and when the acting force also has a component that is offset at an angle to this. Due to the obliquely acting force, the bulge of the covering 22 shown in dashed lines is offset laterally, namely to the side from which the force is applied, and the vertical struts 16 are not bent evenly. On the side from which the force partially acts, the force acting in the first direction 26 is reduced, so that this longitudinal strut 16 is bent less than the remaining longitudinal strut 16 and is thus offset against the longitudinal direction 13. The covering 22 thus hugs the user's back.

The invention is not limited to the embodiments described above. Rather, other variants of the invention can also be derived from this by the person skilled in the art without departing from the subject matter of the invention. In particular, all of the individual features described in connection with the individual embodiments can also be combined with one another in other ways without departing from the subject matter of the invention.

List of reference symbols

2

Seating

4

Seat

6

frame

8th

Chair column

10

Base

12

Boom arm

13

Longitudinal direction

14

backrest

16

Vertical brace

18

Mounting strut

20

top end

22

Covering

24

Edge

26

second direction

28

first direction

30

kink

Claims (9)

Seating furniture (2), in particular an office chair, with a seat (4) and a backrest (14) which has two vertical struts (16) which are spaced apart from one another and are covered with a covering (22), wherein the vertical struts (16) are more elastic in a first direction (28) compared to a second direction (26) perpendicular thereto, and wherein the two first directions (28) are directed in a longitudinal direction (13) of the seating furniture (2) and towards one another. Seating (2) by Claim 1 , characterized in that the covering (22) is slack and inelastic. Seating (2) by Claim 1 or 2 , characterized in that the two vertical struts (16) are not supported on each other between their half and at least one upper end (20). Seating (2) by Claim 3 , characterized in that the upper ends (20) are also not supported on one another. Seating furniture (16) according to one of the Claims 1 until 4 , characterized in that the two vertical struts (16) below the seat surface (4) are connected to a common fastening strut (18). Seating furniture (2) according to one of the Claims 1 until 5 , characterized in that the vertical struts (16) are prestressed. Seating furniture (2) according to one of the Claims 1 until 6 , characterized in that each vertical strut (16) has a rectangular cross-section in a horizontal plane which extends along the second direction (26). Seating (2) by Claim 7 , characterized in that the two first directions (28) are arranged at right angles to each other. Seating (2) by Claim 7 or 8th , characterized in that the extension of the cross-section in the second direction (26) is shortened with increasing height of the plane.

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