Classifications

• • A—HUMAN NECESSITIES
  • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
  • A47C—CHAIRS; SOFAS; BEDS
  • A47C7/00—Parts, details, or accessories of chairs or stools
  • A47C7/36—Support for the head or the back
  • A47C7/40—Support for the head or the back for the back
  • A47C7/46—Support for the head or the back for the back with special, e.g. adjustable, lumbar region support profile; "Ackerblom" profile chairs
  • A47C7/462—Support for the head or the back for the back with special, e.g. adjustable, lumbar region support profile; "Ackerblom" profile chairs adjustable by mechanical means
  • A47C7/465—Support for the head or the back for the back with special, e.g. adjustable, lumbar region support profile; "Ackerblom" profile chairs adjustable by mechanical means by pulling an elastic cable
• • A—HUMAN NECESSITIES
  • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
  • A47C—CHAIRS; SOFAS; BEDS
  • A47C7/00—Parts, details, or accessories of chairs or stools
  • A47C7/36—Support for the head or the back
  • A47C7/40—Support for the head or the back for the back
  • A47C7/44—Support for the head or the back for the back with elastically-mounted back-rest or backrest-seat unit in the base frame
  • A47C7/445—Support for the head or the back for the back with elastically-mounted back-rest or backrest-seat unit in the base frame with bar or leaf springs
• • A—HUMAN NECESSITIES
  • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
  • A47C—CHAIRS; SOFAS; BEDS
  • A47C7/00—Parts, details, or accessories of chairs or stools
  • A47C7/36—Support for the head or the back
  • A47C7/38—Support for the head or the back for the head

Definitions

• the invention relates to a backrest, in particular an office chair, with two backrest areas and a lumbar support.
• the shape of the leaning front outer contour of the backrest can be more or less adapted to the typical S-shape of a spine here. Also, alternatively or additionally, a Lurdose ⁇ si Jardine be provided in the lumbar region of the back of the user person.
• the invention is therefore based on the object, a backrest, preferably for a chair, in particular for an office chair, specify, which has a particularly effective lumbar support while maintaining high comfort and low cost.
• the backrest is initially formed of two superposed Lehnenberei- Chen, which are held on a backrest support.
• the two backrest areas are connected to one another in the lordosis region of the back of a user in an articulated manner.
• the two backrest areas are expediently formed in each case by rigid, substantially deformation-resistant backrest cushions.
• the two backrest areas with the formation of an S-shaped support or outer contour leaning front side gapless and backrest arranged spaced from each other.
• the backrest or cushion back release or gap contour allows in a simple and visually virtually invisible manner the desired deformability between the two backrest areas with simultaneous deformation stiffness of the two backrest areas.
• backrest areas are hinged to the backrest support to form a four-bar linkage.
• the pivot points or axes are expediently positioned in such a way that two joints arranged vertically one above the other in the longitudinal direction of the backrest are provided in the lower, seat-near region of the backrest front side, while the two other joints, also vertically offset one above the other in the backrest longitudinal direction on the backrest support are realized.
• a first joint of the effective manner of a four-bar chain hinge connection between the upper backrest portion and the lower backrest area and there again formed in the lordosis support is expediently.
• a second joint is expediently formed between the lower back region and the (lower) support arm of the backrest support.
• This hinge connection in the lordosis area interconnected backrest areas or backrest cushions are supported underneath the backrest support.
• a third joint of this four-bar linkage or articulated connection is formed between the (lower) support link and an articulated (upper) backrest link of the backrest carrier.
• the fourth joint of the four-bar linkage is then expediently formed between the upper backrest region and the (upper) backrest link of the backrest support.
• the two backrest areas and backrest cushions leaning on the top of the backrest support are hinged, in particular suspended on the backrest support quasi.
• the principle of operation of the four-bar chain is thus realized by between the articulated backrest support on the one hand and the flexible connection between the two Lehnen Schlen other hand, the four joints interconnecting links themselves are each rigid.
• the thus formed between the two backrest areas flexible area is located at the level of about the lordosis of the operator and forms the flexible Lordosenst ⁇ tze there.
• the degree of curvature of the flexible lumbar support whose convexity directed towards the back of the operator is maximum in the upright sitting position, continuously decreases depending on the pressure exerted on the backrest (contact pressure) so the lumbar support is increasingly flattening. Due to the four-bar linkage here, the buckling decrease takes place practically independent of where the force or pressure is applied along the backrest. The reason for this is that at such a pressure or force on the backrest along the two backrest areas of the upper backrest arm of the backrest carrier quasi stretches and thus the upper, relatively long backrest area is pulled vertically upwards at the upper back end.
• the joint connection which is effective in the manner of a four-bar chain, is spring-supported at a suitable location.
• a spring element suitable for this purpose can be provided on the joints of the articulated connection or also in the area of the lumbar support of the two-part backrest.
• the spring force of the spring element acts in the direction of the lordosis of the operator, with an inclination of the backrest, this spring force must be overcome and thus the backrest automatically exerts an increasing counterforce against the back of the operator.
• no or little pressure on the backrest, especially in the lumbar region exercised when the operator sits vertically.
• a corresponding spring element may be provided in the form of a leg spring, in particular on the third joint.
• a tension spring can be provided backwards between the two backrest areas or backrest cushions.
• a leaf spring in the area of the lumbar support on the side facing the back of the operator (back of the backrest) of the backrest cushion is particularly advantageous since at this point the spring element or the leaf spring can be fully and thus invisibly upholstered in a particularly simple manner.
• a headrest is attached to the (lower) support arm of the backrest support.
• This includes a support or support frame, in particular with two support legs, which expediently together an obtuse angle! lock in.
• a head restraint in particular a headrest pad, attached.
• the angled shape of the support frame is preferably selected such that the headrest or the head restraint head is vertically aligned with the upper backrest area in a backrest position with a maximum arched lumbar support and protrudes leaning over the upper backrest area in a backrest leaning position.
• the position of the headrest and the corresponding support frame relative to the lower support arm of the backrest support always remains the same, while by pressing the backrest areas or the backrest cushion in the direction of the backrest support to the tilting of the backrest, the distance of the upper backrest portion to the headrest becomes progressively larger, with the result that the shoulder region of the operator tends more towards the rear compared to the head.
• the two mutually connected to form the flexible lumbar support backrest areas or pads are advantageously resistant to deformation and thus rigid move when a load or force of the backrest, especially in a tilt of the backrest in an alternative embodiment with a synchronous mechanism between the backrest and the seat surface of a chair, although the two backrest areas relative to one another, remain undeformed themselves.
• This rigid design of the two backrest areas also ensures the reliable functional principle of Viergeie ⁇ kkette, in which the four individual, geienkig interconnected links to ensure this functional principle are rigid.
• This embodiment thus causes the backrest of an operator against the backrest and also at their additional inclination in the embodiment with a synchronous mechanism, the area spanned by the four-bar chain surface with increasing contact pressure against the backrest area is increasingly smaller.
• This effectiveness and this functional principle corresponds to the natural behavior and comfort desire of an operator, who, while in the upright sitting position desires support from the backrest in the lumbar region, such support in a reclined sitting position - in extreme cases in a lying position - but not needed or wishes.
• This comfort behavior or comfort desire is due to the fact that in the upright sitting position, a vertical load on the spine, while such a burden decreases with increasing inclination of the spine in the horizontal position. So it is more comfortable with increasing inclination in the horizontal position, although the support in the lumbar region decreases accordingly.
• the backrest of the invention justice by the flexible lumbar support in the upright seating position ensures sufficient support in the lumbar region of an operator, with increasing inclination in a reclined sitting position, however, automatically provides a decreasing lordosis support.
• Fig. 1 shows a schematic side view of the backrest-seat portion of a chair with a flexible lumbar support having backrest with graphically highlighted four-bar chain in the starting position
• Fig. 2 in a representation of FIG. 1, the backrest in a force or pressurized position with flattened lumbar support
• Fig. 3 the backrest of FIG. 1 with headrest
• FIG. 5 shows the embodiment of the backrest according to FIG. 3 in conjunction with a
• Fig. 6 shows the embodiment of FIG. 5 at synchronously inclined backrest and seat.
• the chair 1 constructed as an office chair according to FIGS. 1 to 6 comprises a backrest support 2 connected to a base indicated in FIGS. 5 and 6, on which a two-part backrest 3 with an upper backrest region 3a and a lower backrest region 3b is articulated.
• the backrest support 2 comprises a lower support arm 20 and an upper backrest link 21 articulated therewith.
• the comparatively short L-leg extending in the z-direction and extending comparatively long in the z-direction approximately vertically extending L-leg 20a 20b carries a seat 4.
• This flexible connection between the comparatively long, upper back region 3a and the comparatively short, lower back region 3b is produced in the exemplary embodiment by a back recess or recess 7 within the otherwise dimensionally stable or deformation-resistant - and thus rigid - backrest cushion 3.
• This is essential in that both the upper back region 3a and the lower back region 3b are correspondingly resistant to deformation or rigid, while the intermediate region in which the lumbar support 5 is located is flexible and, in particular, flexibly deformable.
• This flexibility or deformability in turn is such that virtually in this area of the lumbar support 5 between the otherwise rigid upper backrest area and the likewise rigid lower backrest area 3b quasi a (first) joint 8a of an effective manner of a four-bar linkage joint 8 is formed.
• first joint 8a there is also a second joint 8b on the back of the backrest and offset there in the (-) x-direction and in the z-direction below the first joint 8a.
• the two further joints 8c and 8d of the four-bar linkage 8 are located at the back of each other on both sides of the upper backrest link 21.
• the third articulation 8c forming the articulated connection between the support link 20 and the backrest link 21 is located above the first articulation 8a and in the z direction. -) offset x direction to the second joint 8b.
• the fourth joint 8d forms an articulated connection between the upper backrest handle 21 of the backrest support 20 and the upper side of the upper backrest region 3a.
• This fourth joint 8d is positioned in the z-direction above the third joint 8c and in the z-direction between the second joint 8b and the third joint 8c.
• the rigid chain links associated with the formation of the four-bar chain 8 are illustrated by the virtual connecting lines between the four joints 8a to 8d. The realization of these rigid joints is ensured by the rigid arms 20,21 of the backrest support 20 on the one hand and by the rigid back areas 3a and 3b on the other.
• a contact force F exerted by the back of an operator in the direction of the arrow ((-) x-direction) causes the upper back arm 21 to pivot about the third joint 8c with the result that the upper arm Lehnen Schl 3a is pulled almost vertically in the z-direction.
• pivoting of the lower back region 3b about the second joint 8b takes place again in the (-) x direction, with the result that the first joint 8a also moves in the (-) x direction to the direction shown in the illustrations according to FIGS 4 fixed lower support arm 20 to move.
• the degree of curvature of the bulge 6 of the lumbar support 5 decreases from the maximum bulge 6 according to FIG. 1 into the minimal bulge 6 according to FIG. 2.
• the by the four-bar chain 8 spanned area increasingly smaller, as can be seen by a comparison between the illustrations of Figs. 1 and 2.
• FIG. 3 shows alternative positions and configurations of the spring element in the form of a leaf spring 9, a tension spring 10 and / or a leg spring 11.
• leaf spring 9 this is expediently in the area of the lumbar support 5 and there in the area of the first joint 8a the four-bar chain 8 is provided.
• the tension spring 10 is expediently used in the region of the third joint 8c.
• the tension spring 10 is provided on the back side between the two backrest areas 3a and 3b in the recess 7 extending transversely to the xz plane and connected there on the one hand to the upper backrest area 3a and, on the other hand, to the lower backrest area 3b.
• FIGS. 1 and 2 which is otherwise identical to the embodiments according to FIGS. 3 and 4 additionally has a headrest 12.
• This consists essentially of a turn about L-shaped angled support or Tragge- rack 13 and an example pillow-like head restraint head 14.
• the headrest consists essentially of a turn about L-shaped angled support or Tragge- rack 13 and an example pillow-like head restraint head 14.
• the particular obtuse angle assumed between this L-leg 13a and the L-leg 13b of the support frame 13 supporting the headrest main 14 is dimensioned such that the actual headrest, i. the head restraint head 14 in a backrest starting position with a maximum arched lumbar support 5 in a vertical or z-direction is aligned with the upper backrest region 3a, as can be seen from FIG.
• the head restraint head 14 projects beyond the upper backrest area 3a in the x direction in the backrest inclination position shown in FIG.
• the synchronous mechanism 15 essentially comprises two seat arms 16, 17, which are articulated on the seat carrier 18, which is indicated only schematically.
• the front seat link 16 via hinges 16a and 16b with the seat surface 4 on the one hand or with the seat support 18 on the other hand hinged.
• the rear seat link 17 is articulated via hinge connections 17a and 17b to the seat surface 4 on the one hand and the seat support 19 on the other hand.
• the synchronizing mechanism 15 causes a synchronous inclination movement of both the backrest and the seat surface 4 back and down.
• the relationships relative to the backrest itself with respect to the relative movement between the two backrest portions 3a and 3b and the two-part backrest support 2 corresponds to the movement behavior of the backrest according to FIGS. 1 to 4 with a continuous decrease in the degree of bulge of the Auswöibung 6 of the lumbar support 5 with increasing contact pressure F. or pressurization with the difference that at the same time the backrest support 2 tilts backwards and downwards.
• Leaf spring 0 Tension spring 1 Torsion spring 2 Head rest 3 Carrying support frame 3a, b L-leg 4 Headrest main pad 5 Synchronous mechanism 6 Seat link 6a, b Joint connection 7 Seat link 7a, b Joint connection 8 Seat support 0 Support link 0a, b L-leg 1 Backrest link

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chairs For Special Purposes, Such As Reclining Chairs (AREA)
• Chair Legs, Seat Parts, And Backrests (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=40202030

Family Applications (1)

Country Status (5)

Cited By (3)

Families Citing this family (9)

Family Cites Families (7)

• 2007
  • 2007-09-15 DE DE102007044130A patent/DE102007044130A1/de not_active Withdrawn
• 2008
  • 2008-08-08 WO PCT/EP2008/006559 patent/WO2009033535A1/fr active Application Filing
  • 2008-08-08 AT AT08801543T patent/ATE529020T1/de active
  • 2008-08-08 ES ES08801543T patent/ES2375890T3/es active Active
  • 2008-08-08 EP EP08801543A patent/EP2187782B1/fr active Active

Non-Patent Citations (1)

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