U.S. patent application number 10/075034 was filed with the patent office on 2002-08-15 for article of furniture for sitting.
Invention is credited to Hansen, Eckhard.
Application Number | 20020109384 10/075034 |
Document ID | / |
Family ID | 7673984 |
Filed Date | 2002-08-15 |
United States Patent
Application |
20020109384 |
Kind Code |
A1 |
Hansen, Eckhard |
August 15, 2002 |
Article of furniture for sitting
Abstract
An article of furniture for sitting has a seat element, a back,
a support frame having a support and a mechanical structure for
transmitting a movement, which connects the support in a rear seat
region with the seat element, at least one spring element
displacing the seat element in an abutment or return position, the
spring element being formed as a front mounting for the seat
element and supported on the support which is stationary, the
spring element in addition to known restoring function also
determining a guidance of the seat element in its front region.
Inventors: |
Hansen, Eckhard;
(Margrethen, CH) |
Correspondence
Address: |
STRIKER, STRIKER & STENBY
103 East Neck Road
Huntington
NY
11743
US
|
Family ID: |
7673984 |
Appl. No.: |
10/075034 |
Filed: |
February 12, 2002 |
Current U.S.
Class: |
297/300.1 |
Current CPC
Class: |
A47C 1/03277 20130101;
A47C 1/03266 20130101; A47C 1/03255 20130101; A47C 1/03272
20130101; A47C 1/03261 20130101 |
Class at
Publication: |
297/300.1 |
International
Class: |
A47C 001/038 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 12, 2001 |
DE |
101 06 792.5 |
Claims
What is claimed as new and desired to be protected by Letters
Patent is set forth in the appended claims.
1. An article of furniture for sitting, comprising a seat element;
a back; a support frame having a support and a mechanical means for
transmitting a movement, which connects said support in a rear seat
region with said seat element; at least one spring element
displacing said seat element in an abutment or return position,
said spring element being formed as a front mounting means for said
seat element and supported on said support which is stationary,
said spring element in addition to known restoring function also
determining a guidance of said seat element in its front
region.
2. A sitting article of furniture as defined in claim 1, wherein
said mechanical means for transmitting a movement include lever
means.
3. A sitting article of furniture as defined in claim 1, wherein
said mechanical means for transmitting a movement include guide
means.
4. A sitting article of furniture as defined in claim 1, wherein
said spring element is formed as a leaf spring which is tensioned
at one side.
5. A sitting article of furniture as defined in claim 4, wherein
said leaf spring extends in a seat direction.
6. A sitting article of furniture as defined in claim 1, wherein
said spring element has an adjustable spring force.
7. A sitting article of furniture as defined in claim 3, wherein
said spring has a support point, said leaf spring being adjustable
by displacing said support point.
8. A sitting article of furniture as defined in claim 3, wherein
said leaf spring has a spring force which is adjustable by changing
a distance between individual leaves of said leaf spring.
9. A sitting article of furniture as defined in claim 1, wherein
said spring element is formed as a helical spring.
10. A sitting article of furniture as defined in claim 1, wherein
said spring element is formed as a rubber element.
11. A sitting article of furniture as defined in claim 1, wherein
said spring element is formed as a metal rubber element.
12. A sitting article of furniture as defined in claim 1, wherein
said spring element is formed as a hydraulic cushion.
13. A sitting article of furniture as defined in claim 1, wherein
said spring element is formed as a pneumatic cushion.
14. A sitting article of furniture as defined in claim 1; and
further comprising a back support which is connected with said
means for transmitting movement, said back being mounted on said
back support.
15. A sitting article of furniture as defined in claim 1, wherein
said back is mounted on said seat element; and further comprising a
transition region provided between said back and said seat
element.
16. A sitting article of furniture as defined in claim 15, wherein
said transition region is springy.
17. A sitting article of furniture as defined in claim 15, wherein
said transition region is elastic.
18. A sitting article of furniture as defined in claim 15, wherein
said back and said seat element together form a seat shell.
19. A sitting article of furniture as defined in claim 1, wherein
said seat element has a rest member and a base plate which are
displaceable relative to one another.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates generally to articles of
furniture, and in particular to an article of furniture for
sitting.
[0002] The German patent document DE 196 07 136 A1 discloses a
chair with a so-called synchronizing mechanical system. The
synchronizing mechanical system is used for backing in the chair
and, in addition to a tilting movement of the back rearwardly,
provides the lowering of the seat element in a rear seating region
which is close to the back and lifting the seating element in a
front seat region which is remove from the back. Therefore the
sitting person during backing has the feeling of sliding into the
chair and not the filling of sliding from the chair. With a spring
element which acts on a suspension arranged in the front seat
region on the seat element, the seat element is adjusted in an
initial position. Against the force which must hold the seat
element in the back in the initial position, the sitting person
must apply a force against the back and against the spring element
for reaching a back tilting of the chair or a change in angular
position of the seat element. A movement of the seat element is
possible substantially only by loading or unloading of the back.
The front region of the seat element is in a fixed predetermined
position when the back is unloaded. The movements of the seat
element are provided by levers and/or guides. It is believed to be
advisable to further improve the existing chairs.
SUMMARY OF THE INVENTION
[0003] Accordingly, it is an object of present invention to provide
an article of furniture for sitting which avoids the disadvantages
of the prior art.
[0004] More particularly, it is an object of the present invention
to provide an article of furniture for sitting which in addition to
the comfort provided by the synchronizing mechanical system
provides further comfort properties in the region of the seat
element and a simplified construction of the synchronizing
mechanical system.
[0005] In keeping with these objects and with others which will
become apparent hereinafter, one feature of the present invention
resides, briefly stated, in an article of furniture for sitting,
comprising a seat element; a back; a support frame having a support
and a mechanical means for transmitting a movement, which connects
said support in a rear seat region with said seat element; at least
one spring element displacing said seat element in an abutment or
return position, said spring element being formed as a front
mounting means for said seat element and supported on said support
which is stationary, said spring element in addition to known
restoring function also determining a guidance of said seat element
in its front region.
[0006] The article of furniture for sitting in accordance with the
present invention has front mounting means for the seat element
which is formed as a spring element supported on a stationary
support part, wherein the spring element takes over, in addition to
the known restoring function, also the guidance of the seat element
in its front region. Thereby the components which are required for
holding and guiding the spring element as disclosed in the German
patent document DE 196 07 136 A1 in the chair with a synchronizing
mechanical system are no longer necessary to guide the force of the
spring and to control a part of the movement course of the seat
element.
[0007] Furthermore such a double function or double functions of
the spring increase the comfort or the suitability of the chair for
persons with any size and any body weight. This results from the
fact that the opening angle between the seat element and the back
due to the construction of the inventive spring element is no
longer determinable alone by the size of the force against the back
and thereby the inclination of the chair. An increase of the
opening angle between the seat element and the back which often is
desired for heavier persons with a greater body volume can be
adjusted now substantially automatically in that the person with a
greater body weight and a greater body volume applies a greater
force to the spring element and in contrast to the known spring
element in the German patent document DE 196 07 136 A1 it has the
freedom to deviate in a substantially perpendicular direction.
Thereby the seat element is tilted forwardly or sinks in a forward
region and obtains independently from the position unloading of the
back an increase opening angle between the back and the seat
element. In addition to this comfort for the person with a greater
body weight and a greater body volume, a further advantage is
provided for a person which sits in the front region of the seat
element. Such a sitting position is often assumed by persons who
operate at a computer. In such a working position it has been found
as advantageous when the seat surface is inclined slightly
forwardly. This orientation of the seating means is also provided
by the additional freedom of the inventive spring element. The
person which is loaded in such a seat position of the seat element
presses with a small body weight the center of gravity of the body
located in this position substantially over the front edge of the
seat element the spring element downwardly, so that it adjusts the
desired inclination of the seat element forwardly. This position of
the seat element facilitates and favors a favorable body hold from
the medical point of view, in which the pelvis of the sitting
person is tilted forwardly.
[0008] In accordance with another advantageous embodiment of the
invention, the spring element is formed as a leaf spring which
extends and is bent preferably in a seat direction. A leaf spring,
in other words an individual leaf spring or a leaf spring pack
satisfies the requirements of the spring element in an ideal
fashion, since the bent leaf spring applies passing forces in the
both required directions. On the one hand the leaf spring acts
upwradly. Thereby the seat element is lifted or held in the front
region. On the other hand the leaf spring acts forwardly in seat
direction. Thereby the seat element is loaded with a force
forwardly and thereby acts for lowering of the rear seat region.
Thereby the leaf spring holds the seat element and with it also the
back directly or indirectly connected to it, in a front abutment or
at a storing position. A backing in the chair leads depending on
the shape or bending of the leaf spring, in addition to a sinking
of the rear seat region, to a lifting of the front seat region or
to a retention of the front seat region at a certain height.
[0009] An adjustability of the spring element allows the
maintaining the seat element optimal to the requirements or desires
of the sitting person. In particular a small, light person can
increase the opening angle between the seat means and the back
without tilting back. Simultaneously through the adjustment of the
force of the spring element, also the tilting ability or tilting
conditions of the chair can be influenced.
[0010] In accordance with another special embodiment of the
invention, the spring force of the leaf spring can be varied by
displacement of the spring abutment point and/or a change of the
distance between the individual spring sheets. These adjustments
can be realized by an specially simple and therefore cost-favorable
adjusting mechanism.
[0011] Furthermore, it is advantageous when the spring element is
formed as helical springs and/or rubber elements, and/or
rubber-metallic elements, and/or hydraulic cushions and/or
pneumatic cushions, or a combination of these elements. These
spring elements provide an adaptation to different requirements and
mounting possibilities.
[0012] It is especially advantageous when the invention is utilized
in a chair with a back, which is connected through a back support
with the means for movement transmission. With this arrangement a
chair completely maintain a comfort, which goes beyond the comfort
of the chair of the prior art.
[0013] It is further proposed to provide the chair with the
inventive comfort function in which the back is directly connected
to the seat element. Thereby a mechanically simple and
cost-favorable chair is formed with a high comfort. In a transition
region from the seat element to the back, of an elastic chair an
article of furniture for sitting is formed which despite its simple
construction provides the comfort of the above described
chairs.
[0014] With the use of a seat element which is composed of a base
plate and a support displaceably arranged on it, it is possible to
adapt the chair in the sitting region optimally to the required
supporting surface for the hip of the person sitting on the chair.
Thereby the suitability of the chair for persons of different body
sizes and body weights is increased.
[0015] The novel features which are considered as characteristic
for the present invention are set forth in particular in the
appended claims. The invention itself, however, both as to its
construction and its method of operation, together with additional
objects and advantages thereof, will be best understood from the
following description of specific embodiments when read in
connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a side view of office chair in accordance with a
first embodiment of the present invention in a forward abutment
position;
[0017] FIG. 2 is a side view of the office chair shown in FIG. 1 in
the rear abutment position;
[0018] FIG. 3 is a plan view of the office chair in accordance with
the present invention shown in FIG. 1;
[0019] FIG. 4 is a side view of an office chair in accordance with
a second embodiment of the present invention in a front abutment
position;
[0020] FIG. 5 is a side view of the inventive office chair shown in
FIG. 4 in the rear abutment position;
[0021] FIG. 6 is a plan view of the inventive office chair of the
embodiment of FIG. 4;
[0022] FIG. 7 is a side view of an office chair in accordance with
a third embodiment of the present invention, in a front abutment
position;
[0023] FIG. 8 is a side view of the inventive office chair of FIG.
7 in the rear abutment position;
[0024] FIG. 9 is a plan view of the inventive office chair shown in
FIG. 7;
[0025] FIG. 10 is a side view of an office chair in accordance with
a fourth embodiment of the present invention in the front abutment
position;
[0026] FIG. 11 is a side view of the inventive office chair of FIG.
10 in the front abutment position;
[0027] FIG. 12 is a plan view of the inventive office chair of FIG.
10;
[0028] FIG. 13 is a side view of an office chair in accordance with
a fifth embodiment of the present invention in the front abutment
position;
[0029] FIG. 14 is a side view of the inventive office chair of FIG.
18 in the rear abutment position;
[0030] FIG. 15 is a plan view of the inventive office chair of FIG.
13;
[0031] FIG. 16 is a side view of an office chair in accordance with
the a sixth embodiment of the present invention in the forward
abutment position;
[0032] FIG. 17 is a side view of the inventive office chair of FIG.
13 and the rear abutment position; and
[0033] FIG. 18 is a plan view of the inventive office chair of FIG.
16.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] FIG. 1 shows a side view of an article of furniture for
sitting 1 which is formed as an office chair 2. The office chair 2
substantially has a rotary frame 3 with rollers 4, which is
connected through an axle 5 with a supporting part 6 in a
vertically adjustable and rotatable manner. It also has a seat
element 7 mounted on the supporting part 6 and a back 9 which is
connected with support part 6 through a back support 8.
[0035] The support part 6 is composed of a rigid support 10 which
receives the axle 5, means 11 for transmission of a movement which
are formed as levers 12, and a front mounting means 14 which is
formed as a spring element 15. The seat element 7 is composed of a
support member 16 and a base plate 17. The support member 16 is
displaceable relative to the base plate 17 in a seat direction A
between a first position P and a second position P', and is
arrestable. Due to such a displacement, the supporting surface for
the hip of a person who sits on the office chair 2 is individually
adujustable.
[0036] Forward flange means 19, 20 are arranged in a front seat
region 18 on the seat element 7 or on the base plate 17, and rear
flange means 22, 23, are arranged in a rear seat region 21 of the
same, as shown in FIG. 3. The first flange means 19, 20 receive
each a spring element 15, wherein the spring elements 15 are formed
as leaf springs 24, 25. The leaf springs 24, 25 act as springy
jibs, so that the seat element 7 is rotatably hinged on their free
ends through the front flange means 19, 20.
[0037] In FIG. 1 the office chair 2 is shown in an upright or front
abutment position I, which it assumes in a condition in which it is
not loaded with a person or in other words it is unloaded. In this
front abutment position I the spring element 15 lifts due to a
vertically acting force F.sub.z in the arrow direction Z of the
seat element 7 at a height H. Furthermore, a horizontal force
F.sub.x of the spring element 15 pulls the seat element 7 in arrow
direction x to the position I shown in FIG. 1. The spring force
acts through the rear flange means 22, 23 also on the lever 12 and
the back support 8 which are connected to the support 10 turnably
about an axis 26. Through the lever 12 a circular path K is
defined, over which an axle 27 connecting the rear flange means 22,
23 with the levers 12 or the back support 8 can move.
[0038] By loading of the office chair 2 with the force F.sub.s by a
person sitting on the office chair 2 the seat element 7 turns by
the portion of the force F.sub.s acting in the front seating
region, substantially against the clockwise direction around the
bearing point 27 until the portion of the force F.sub.s is
compensated by the force F.sub.z of the spring element 15 acting
opposite to it. The portion of the force F.sub.s acting in the rear
seat region is taken for the lever 12, the support part 10, the
axle 5 and the rotary frame or a pulling force by the spring
element 12 acts through the lever 12 which is compensated by this
force component F.sub.s. Therefore depending on the acting forces
F.sub.s and F.sub.z an inclined position of the seat element 7
results for example in an inclined position 28 identified with a
broken line. Thereby an opening angle a enclosed between the back 9
and the seat element 7 is increased to an opening angle .alpha.'. A
lowering of the seat element 7 can be performed both by a person
which has contact of his back against the back of the chair 9,
which seats exclusively in the front of the seat region 19. Such a
person understandably provides a greater inclined position of the
seat surface 7, when it sits exclusively in the front seat region
18, since then van a greater part of the body weight acts on the
spring element 15.
[0039] FIG. 2 shows the office chair 2 of FIG. 1 in a rear abutment
position 11. The office chair 2 in this position is held by a
force. F.sub.R originates from the sitting person and acting on the
back 9. The force F.sub.R is compensated by the force F.sub.x of
the spring element 15. Thereby the movement of the back 9 and the
seat element 7 is limited by the spring element 15. Substantially
the force F.sub.R is transmitted through the back support 8 and the
seat element 7 as a pulling force with a spring element 15, while
the axle 27 assumes the position shown in FIG. 2 by a turning on
the circular path K from the position shown in FIG. 1. The force
F.sub.R activates thereby, via the synchronous mechanical system,
or in other words the special connection of the back 9 and the seat
element 7, in addition to the turning of the back 9 in a clockwise
direction, also a movement of the axle 27 in counterclockwise
direction over the circular path K which is originated by a
rotation of the seat element in a clockwise direction around the
axle 27. Thereby by the synchronous mechanical system a typical
sinking of the seat element 7 is produced in the rear seat region
21, and a lifting of the seat element 7 in the front seat region
18.
[0040] These movements produced by the synchronous mechanical
system are superposed by a further movement which makes possible
the unguided spring element. The further movement results in that
the sitting person acts with a force F.sub.S on the seat surface 7,
with a part of this force applied in the front seat region 18
compensated by the force F.sub.Z of the spring element 15.
Depending on the magnitudes of the acting forces F.sub.Z and
F.sub.x , a changeable opening angle which is changed relative to
the opening angle a of FIG. 2 is produced. Thereby the opening
angle is not determined by the synchronous mechanical system alone,
but substantially is a function of the forces F.sub.S and
F.sub.z.
[0041] FIG. 3 shows a plan view of the office chair 2 of FIG. 1,
wherein the illustration of the rotary frame and the rollers is
dispensed with, however the other components located under the seat
element 7 are shown. In the region of the back 9 this illustration
is also simplified. The support 10 is U-shaped and receives the
spring element 15 at the free legs 29, 30. The back support 8 is
arranged in the rear flange means 22, 23, and the lever 20 is
formed as a fork 31.
[0042] FIGS. 4-6 show a second embodiment of the office chair 32.
In contrast to the embodiments of FIGS. 1-3, the office chair has
means 33 for adjusting the spring force of the spring element 15.
As means 33 for adjusting the spring force, a tensioning device 34
is proposed. The tensioning device 34 has a hand wheel 35 which
actuates the not shown tensioning screw for changing the distance
between individual spring leaves 36 on the spring element 15. A
smaller distance between the spring leave 36 provides a greater
tensioning force of the spring element 15. Furthermore, the office
chair 32 shown in FIGS. 4-6 is also different from the office chair
of FIGS. 1-3 in that, for the springing of a seat element 7 only
one spring element 15 is utilized. Thereby a particularly narrow
construction of the office chair 32 is possible.
[0043] FIGS. 7-9 show a third office chair 37. In contrast to the
office chair 32 shown in FIGS. 4-6, a spring element 15 is formed
as a rubber element 38 or a rubber metal 39. As a rubber metal, a
synthetic plastic element, in particular a rubber element provided
between two metal plates is utilized. The spring element 15 has
spring properties acting in x and z directions. A springing in a
transverse direction y is provided by the mechanical connection of
a seat element 7 through a lever 12 to a support 10. When the
office chair 37 shown in FIG. 8 is in a rear abutment position II,
then the spring element 15 is subjected to a shearing load. Its
acts in all positions in which the office chair 37 assumes a
position in which a back 9 is inclined relative to the position
shown in FIGS. 7.
[0044] FIGS. 10-12 show an office chair 40 in accordance with a
fourth embodiment of the present invention which is substantially
similar to the third office chair of FIGS. 7-9. In this office
chair the spring element 15 is formed as a helical spring 41. As
for the operation, here the description of the office chair of
FIGS. 7-9 is applicable since the helical spring element 41 is
comparable with the rubber element 38 or the rubber metal 39.
[0045] An office chair 42 in accordance with a fifth embodiment of
the present invention is shown in FIGS. 13-15. In contrast to the
office chair shown in FIGS. 1-12, the office chair 42 has a seat
shell 43. The seat shell 43 is composed of a back 9 which is
connected of one piece with a seat element 7. The seat shell 43 in
a transition region 44 is elastic or springy. A partial function of
the synchronous mechanical system namely the increase of an opening
angle a between the back 9 and the seat 7 is taken in the office
chair 42 by the flexible or elastic transition region 44, which
activates a back springing of the back 9 in dependence on the force
F.sub.R acting on it and applied by a person sitting on the office
chair 42. Similarly to the office chairs shown in FIGS. 1-12 the
force F.sub.R , depending on the counter force F.sub.X produced by
a spring element 15, activates sinking of the seat shell 43 in the
rear seat region 21 and lifting the seat shell 43 in a front seat
region 18. A weight force F.sub.S applied by a sitting person or
its portion acting in the front seat region 18 leads to a lowering
of the seat element contrary the clockwise direction. In the office
chair 42 it provides driving the back when the opening angle a of
the seat shell 43 is not increased by an increasing force F.sub.R
acting on the back 9.
[0046] A sixth office chair 45 is shown in FIGS. 16-18. The office
chair 45 has, as the office chair 42 shown in FIGS. 13-15, a seat
shell 43 which is composed of a seat element 7 and a back 9 springy
connected in a transition region. In contrast to the office chairs
shown in FIGS. 1-15, in the office chair 45 the rotatably connected
lever which serves as means 11 for transmission of a movement, is
replaced by guides 13. The guides 13 are formed as elongated
openings 46 provided in beams 47. The beams 47 are fixedly
connected with a support 10. Rear flange means 22, 23, which are
fixedly connected with the seat shell 43 are supported in a
longitudinal openings 46 through a throughgoing axle 27.
[0047] The invention is not limited to the shown and described
embodiments. It includes many further modifications of the
invention within the range of the protection rendered by the
claims. In particular, it is possible to provide the inventive
arrangement of a spring element also on furniture articles for
sitting which do not have a rotary frame, but instead have standing
legs or standing feet and/or are fixedly mounted.
[0048] It will be understood that each of the elements described
above, or two or more together, may also find a useful application
in other types of constructions differing from the types described
above.
[0049] While the invention has been illustrated and described as
embodied in sifting article of furniture, it is not intended to be
limited to the details shown, since various modifications and
structural changes may be made without departing in any way from
the spirit of the present invention.
[0050] Without further analysis, the foregoing will so fully reveal
the gist of the present invention that others can, by applying
current knowledge, readily adapt it for various applications
without omitting features that, from the standpoint of prior art,
fairly constitute essential characteristics of the generic or
specific aspects of this invention.
* * * * *