U.S. patent application number 12/878573 was filed with the patent office on 2011-03-17 for item of seating furniture with seat depth adjustment.
Invention is credited to Mark Wiese.
Application Number | 20110062758 12/878573 |
Document ID | / |
Family ID | 41800389 |
Filed Date | 2011-03-17 |
United States Patent
Application |
20110062758 |
Kind Code |
A1 |
Wiese; Mark |
March 17, 2011 |
Item of Seating Furniture with Seat Depth Adjustment
Abstract
An item of seating furniture employs a seat depth adjustment, in
which the seat is mounted displaceably relative to a backrest
frame. A pivotable lower backrest frame is mounted on the backrest
frame. The lower backrest frame is connected to the rear part of
the seat. The displaceable seat thereby remains connected to the
backrest, and a horizontal gap does not arise between the backrest
and seat, which horizontal gap could impair the seating comfort and
interfere in the overall appearance of the item of seating
furniture. The seat depth adjustment is in particular also suitable
for use with synchronous mechanisms.
Inventors: |
Wiese; Mark; (Ahlen,
DE) |
Family ID: |
41800389 |
Appl. No.: |
12/878573 |
Filed: |
September 9, 2010 |
Current U.S.
Class: |
297/284.8 ;
297/340 |
Current CPC
Class: |
A47C 1/023 20130101;
A47C 7/46 20130101; A47C 1/03255 20130101 |
Class at
Publication: |
297/284.8 ;
297/340 |
International
Class: |
A47C 7/46 20060101
A47C007/46; A47C 1/032 20060101 A47C001/032; A47C 3/20 20060101
A47C003/20 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 16, 2009 |
EP |
09011823.3 |
Claims
1. Item of seating furniture with a seat and a backrest frame,
wherein the seat is displaceable relative to the backrest frame in
order to change the seat depth, characterized by a lower backrest
frame which is connected to the rear part of the seat and is
mounted pivotably on the backrest frame.
2. Item of seating furniture according to claim 1, with a lumbar
support carrier which is fastened at one end to the backrest frame
and at the other end to the lower backrest frame and carries a
lumbar support.
3. Item of seating furniture according to claim 2, wherein the
lumbar support carrier has a transverse carrier and a longitudinal
carrier which is connected to the transverse carrier and to the
lower backrest frame, wherein the lumbar support is mounted
displaceably on the longitudinal carrier.
4. Item of seating furniture according to claim 3, wherein the
longitudinal carrier has a telescopic structure.
5. Item of seating furniture according to claim 1, wherein the
lumbar support is provided with adjustment means for adjusting the
supporting depth.
6. Item of seating furniture according to claim 2, wherein the
lumbar support is provided with adjustment means for adjusting the
supporting depth.
7. Item of seating furniture according to claim 3, wherein the
lumbar support is provided with adjustment means for adjusting the
supporting depth.
8. Item of seating furniture according to claim 4, wherein the
lumbar support is provided with adjustment means for adjusting the
supporting depth.
Description
BACKGROUND
[0001] This disclosure relates generally to an item of seating
furniture, in particular a chair, with a seat depth adjustment.
[0002] Items of seating furniture of this type, in which the seat
is mounted displaceably for the purpose of adaptation to the leg
length of the seated person, are generally known. In this case,
however, there is the problem that, in at least one extreme
position of the seat, a horizontal gap with respect to frame parts
of the item of seating furniture is produced, which horizontal gap
may impair the seating comfort or in which objects may become
jammed.
[0003] Although it would be possible to design the seat itself to
be in two parts and to be displaceable per se, this interferes in
the overall appearance and likewise impairs the seating
comfort.
[0004] DE 201 08 172 U1 discloses a chair with an adjustable
backrest for adjusting the seat depth. In said known chair, the
backrest is mounted on a pivotable carrier. However, this solution
is relatively complicated and is almost impossible to use with
"synchronous mechanisms". As used herein, the phrase "synchronous
mechanism" relates to a mechanism of a chair where, when leaning
back, the inclination of the backrest also results in an
inclination of the seat via a mechanism coupling the backrest to
the seat.
[0005] By contrast, an item of seating furniture of the type
mentioned at the beginning, in which the seating comfort is not
impaired, is distinguished by a simple construction and also is
being suitable for use with synchronous mechanisms.
SUMMARY
[0006] Briefly stated, it is proposed to mount a pivotable lower
backrest frame on the backrest frame, the lower backrest frame
being connected to the rear part of the seat. The displaceable seat
thereby remains connected to the backrest, and a horizontal gap
does not arise between the backrest and seat, which horizontal gap
could impair the seating comfort and interfere in the overall
appearance of the item of seating furniture.
[0007] The item of seating furniture is preferably provided with a
lumbar support, wherein the lumbar support is fastened on a lumbar
support carrier which is mounted at one end on the backrest frame
and at the other end on the lower backrest frame. The lumbar
support can thereby follow a pivoting of the lower backrest frame
and can thus be kept in an optimum position in relation to the seat
even when the seat depth is adjusted.
[0008] In order to permit simple adjustment of the lumbar support,
the lumbar support carrier is provided with a transverse carrier
and a longitudinal carrier which is connected to the transverse
carrier and to the lower backrest frame, wherein the longitudinal
carrier preferably has a telescopic structure, and the lumbar
support is mounted displaceably on the longitudinal carrier.
[0009] For optimum adaptation to the body build of the seated
person, the lumbar support is preferably provided with adjustment
means for adjusting the supporting depth.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] An embodiment is explained with reference to the attached
drawings, in which:
[0011] FIG. 1 shows a central section of an office swivel
chair;
[0012] FIG. 2 shows a side illustration of the office swivel chair
without a seat cushion;
[0013] FIG. 3 shows a perspective illustration of the frame
construction of the office swivel chair; and
[0014] FIG. 4 shows a top view of the frame construction.
DETAILED DESCRIPTION
[0015] For this purpose, it should be noted that, in the above text
and in the text below, the definitions of "at the front", "at the
rear", "at the top", etc. arise from the normal position of a
chair.
[0016] According to FIG. 1, an office chair comprises a seat with a
seat cushion carrier 5 and a seat cushion 3, and a backrest frame
7. The seat 1 is mounted displaceably forward and rearward on a
seat carrier 9, wherein the seat carrier 9 and the backrest frame 7
are connected to a main carrier 11 which is fastened to a chair
pillar 13. Furthermore, FIG. 1 shows a seat mechanism 19 which
permits a coordinated adjustment of the backrest frame 7 and seat,
but does not relate to the adjustment of the seat depth and
therefore is not explained further.
[0017] A lower backrest frame 17 which is connected at the lower
end thereof to the rear edge of the seat 1 is mounted pivotably on
the backrest frame 7. Furthermore, a lumbar support 15 is provided,
said lumbar support being mounted on a lumbar support carrier
comprising a transverse carrier 21 and a longitudinal carrier
23.
[0018] The arrangement of the last-mentioned elements is apparent
in particular from the perspective illustration of FIG. 3, which
shows the frame construction of the chair without a seat cushion.
It is apparent from the illustration that the transverse carrier 21
extends between two struts of the backrest frame 7. The
longitudinal carrier 23, which extends with respect to a
transversely running strut of the lower backrest frame 17, is
fastened in the center of the transverse carrier 21. Furthermore,
the longitudinal carrier 23 has a telescopic connection 25.
[0019] The backrest frame 17, for its part, is connected to the
backrest frame 7 via an articulated connection 29 comprising
lamellas.
[0020] FIG. 3 furthermore shows that the seat cushion carrier 5 is
designed as a plate which is manufactured from flexible material
and, in the center, has a web 31 extending from the front rearward.
The web 31 rests on the seat carrier 9 (FIG. 1) and can be
connected to the seat mechanism 19. The resting action and the
flexibility permit dynamic seating as the right/left loading
changes.
[0021] In the region of the ischial tuberosities, the seat cushion
carrier is provided with slots 35 which extend parallel to the side
edges of the seat cushion carrier, and with slots 37 which extend
parallel to the rear edge of said seat cushion carrier, in order to
further increase the flexibility.
[0022] In the region of the side edges, the seat cushion carrier 5
is provided with slots 39 which extend from the side edge toward
the web 31. The length of said slots 39 increases the closer said
slots are arranged to the rear edge of the seat cushion carrier
5.
[0023] The precise arrangement of the slots is apparent in
particular from the top view in FIG. 4. This figure furthermore
shows adjustment means 41 for adjusting the supporting depth of the
lumbar support 15, i.e. for adjustment in the seat depth direction.
The adjustment means 41 are designed in such a manner that they
permit a depth adjustment of the lumbar support 15 separately, on
the right and left, such as, for example, via eccentrics.
[0024] As illustrated by the double arrow in FIG. 2, which shows
the chair without a seat cushion, the seat cushion carrier 5 is
mounted displaceably in the depth direction in chair guides. In
this case, the lower backrest frame 17 follows a movement of the
seat cushion carrier 5 such that a horizontal gap cannot be
produced. FIG. 2 shows the seat cushion carrier 5 in a central
position.
[0025] In this regard, it should also be noted that, in the use
state of the chair, the backrest carrier is provided with a fabric
covering, upholstery or the like.
[0026] The seat 1 can be secured in any of the intermediate
positions thereof between the position located furthest to the rear
and the position located furthest to the front. For this purpose, a
rack (not illustrated) is preferably provided on the seat cushion
carrier 5, which rack can be brought into engagement with suitable
tooth elements and can be actuated via a button 43.
[0027] The foregoing description has been explained with reference
to an office swivel chair, but the seat depth adjustment may also
be used in other items of seating furniture, such as four-legged
chairs, armchairs, sofas, etc.
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