U.S. patent application number 14/958815 was filed with the patent office on 2016-06-09 for chair with elastically-deformable seat and backrest.
The applicant listed for this patent is PRO-CORD S.p.A.. Invention is credited to Giancarlo PIRETTI.
Application Number | 20160157615 14/958815 |
Document ID | / |
Family ID | 52130721 |
Filed Date | 2016-06-09 |
United States Patent
Application |
20160157615 |
Kind Code |
A1 |
PIRETTI; Giancarlo |
June 9, 2016 |
CHAIR WITH ELASTICALLY-DEFORMABLE SEAT AND BACKREST
Abstract
A chair comprising: a metal frame formed by a plurality of
tubular metal elements, including a seat portion having two tubular
seat support elements and a backrest portion having two tubular
backrest support elements extending upwardly from the seat portion,
a flexible seat panel of plastic material with high elasticity,
having two lateral tubular portions into which respective tubular
seat support elements are inserted, and a flexible backrest panel
of plastic material with high elasticity having two lateral tubular
portions into which respective tubular backrest support elements
are inserted, wherein in a rest condition there is a transverse
clearance between the outer edges of the lateral tubular portions
of the flexible seat panel and of the flexible backrest panel and
the respective tubular support elements, and wherein in a deformed
condition said transverse clearance is reduced to zero.
Inventors: |
PIRETTI; Giancarlo;
(Bologna, IT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PRO-CORD S.p.A. |
Bologna |
|
IT |
|
|
Family ID: |
52130721 |
Appl. No.: |
14/958815 |
Filed: |
December 3, 2015 |
Current U.S.
Class: |
297/301.1 |
Current CPC
Class: |
A47C 7/44 20130101; A47C
5/06 20130101; A47C 7/002 20130101; A47C 5/04 20130101 |
International
Class: |
A47C 7/44 20060101
A47C007/44; A47C 7/14 20060101 A47C007/14; A47C 7/00 20060101
A47C007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 4, 2014 |
IT |
TO2014A001007 |
Claims
1. A chair comprising: a metal frame formed by a plurality of
tubular metal elements, including a seat portion having two tubular
seat support elements and a backrest portion having two tubular
backrest support elements extending upwardly from the seat portion;
a flexible seat panel of plastic material with high elasticity,
having two lateral tubular portions into which respective tubular
seat support elements are inserted; and a flexible backrest panel
of plastic material with high elasticity having two lateral tubular
portions into which respective tubular backrest support elements
are inserted, wherein, in a rest condition, there is a transverse
clearance between the outer edges of the lateral tubular portions
of the flexible seat panel and of the flexible backrest panel and
the respective tubular support elements and wherein, in a deformed
condition, said transverse clearance is reduced to zero.
2. A chair according to claim 1, wherein in the rest condition,
said transverse clearance of the lateral tubular portions of the
flexible seat panel has a constant value along a longitudinal axis
of the respective tubular seat support element.
3. A chair according to claim 1, wherein in the rest condition,
said transverse clearance varies along a longitudinal axis of the
respective tubular seat support element from a minimum value at a
front edge of the flexible seat panel to a maximum value at a rear
edge of the flexible seat panel.
4. A chair according to claim 1, wherein in the rest condition,
said transverse clearance of the lateral tubular portions of the
flexible backrest panel varies in the vertical direction from a
minimum value at the lower ends of the lateral tubular portions to
a maximum value at the upper ends of the lateral tubular portions
of the flexible backrest panel.
5. A chair according to claim 4, wherein the lateral tubular
portions of the flexible backrest panel are provided with
through-cuts spaced apart in the vertical direction.
6. A chair according to claim 1, wherein said frame comprises two
front leg elements having upper ends connected to respective front
ends of the tubular seat support elements and two rear leg elements
forming a downward extension of the respective tubular backrest
support elements, wherein the lower ends of the front leg elements
and the rear leg elements are interconnected by means of respective
lower longitudinal elements.
7. A chair according to claim 6, wherein the tubular backrest
support elements are fixed to respective lateral ends of a rear
cross member.
8. A chair according to claim 6, wherein said front leg elements
are fixed to respective lateral ends of a front cross member.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of Italian patent
application number TO2014A001007, filed Dec. 4, 2014, which is
herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a chair with
elastically-deformable seat and backrest.
[0004] In particular, the invention relates to a chair having a
metal frame formed by bent tubular elements that carry a seat panel
and a backrest panel.
[0005] 2. Description of Prior Art
[0006] As is well known in the field, to increase the comfort, the
seat and the backrest should adapt to the weight of the user and to
the backward thrust applied by the user's back.
[0007] One method for adapting the geometry of the chair to the
weight of the user and to the backward thrust applied to the
backrest envisages the use of "weight-activated" mechanisms with
tilting and mutually-synchronized seat and backrest.
[0008] A simpler and cheaper way to adapt the geometry of the chair
to the weight of the user and to the backward thrust applied on the
backrest is that of producing the seat and the backrest by means of
deformable elastic elements, for example, sheets of fabric
stretched on lateral supports of the seat and the backrest. These
solutions are generally affected by a limited possibility of
elastic deformation of the sheets forming the seat and the
back.
SUMMARY OF THE INVENTION
[0009] The present invention aims to provide a chair with a simple
structure, characterized by a wide adaptability of the support
surfaces of the seat and the backrest.
[0010] According to the present invention, this object is achieved
by a chair having the characteristics forming the subject of claim
1.
[0011] The claims form an integral part of the disclosure provided
here in relation to the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The present invention will now be described in detail with
reference to the attached drawings, given purely by way of
non-limiting example, wherein:
[0013] FIG. 1 is a front elevational view of an embodiment of a
chair according to the present invention.
[0014] FIG. 2 is a cross-section according to the line II-II of
FIG. 1.
[0015] FIG. 3 is a cross-section of the part indicated with the
arrow III in FIG. 2, illustrating the seat in the deformed
position.
[0016] FIGS. 4 and 5 are cross-sections according to the arrows IV
and V of FIGS. 2 and 3, illustrating the seat in the rest position
and in the deformed position.
[0017] FIGS. 6 and 7 are enlarged details of the parts indicated by
the arrows VI and VII in FIGS. 4 and 5.
[0018] FIG. 8 is a perspective view of the backrest indicated by
the arrow VIII in FIG. 1.
[0019] FIG. 9 is a cross-section on an enlarged scale of the part
indicated by the arrow IX in FIG. 1.
[0020] FIGS. 10 and 11 are cross-sections according to line X-X of
FIG. 1 in the rest position and in the deformed position,
respectively.
DETAILED DESCRIPTION
[0021] With reference to FIGS. 1 and 2, numeral 10 indicates a
chair according to a first embodiment of the present invention. The
chair 10 comprises a metal frame 12 formed of bent tubular metal
elements. The frame 12 includes a seat portion 14 and a backrest
portion 16. The seat portion 14 of the frame 12 comprises two
tubular seat support elements 18 oriented longitudinally and
parallel to each other along opposite lateral sides of the chair
10. The backrest portion 16 of the frame 12 comprises two tubular
backrest support elements 20 parallel to each other and extending
upwardly from the seat portion 14. The tubular backrest support
elements 20 are located on opposite lateral sides of the chair
10.
[0022] The frame 12 of the chair 10 comprises two front leg
elements 22 connected to the front ends of the respective tubular
seat support elements 18. The lower ends of the front leg elements
are connected to the front ends of the respective lower
longitudinal elements 24. The rear ends of the lower longitudinal
elements 24 are connected to lower ends of the respective rear leg
elements 26. The tubular backrest support elements 20 are formed by
upward extensions of the respective rear leg elements 26.
Preferably, the tubular seat support element 18, the front leg
element 22, the lower longitudinal element 24, the rear leg element
26 and the tubular backrest support element 20 on each side of the
chair 10 are formed by a single bent tubular metal element. The
rear end of each tubular seat support element 18 is fixed to the
lower end of the respective tubular backrest support element 20,
coinciding with the upper end of the respective rear leg element
26.
[0023] The two tubular backrest support elements 20 are fixed to
respective ends of a rear cross member 28. The front leg elements
22 are fixed to respective ends of a front cross member 30.
[0024] The chair 10 comprises a flexible seat panel 32 and a
flexible backrest panel 34 formed of molded plastic material with
high elasticity. The flexible seat panel 32 and the flexible
backrest panel 34 are capable of elastically deforming according to
an arcuate shape and of returning to the initial shape when the
force causing the deformation ceases. Suitable materials are, for
example, nylon and polyoxymethylene (POM).
[0025] The flexible seat panel 32 and the flexible backrest panel
34 have respective lateral tubular portions 36, 38, integrally
formed with the respective panels 32, 34. The tubular seat support
elements 18 extend through the lateral tubular portions 36 of the
flexible seat panel 32. The tubular backrest support elements 20
have respective upper ends inserted within respective lateral
tubular portions 38 of the flexible backrest panel 34.
[0026] With reference to FIGS. 2 to 5, in rest conditions, the
flexible seat panel 32 has an essentially flat shape. With
reference to FIGS. 4 and 6, in rest conditions, in each lateral
tubular portion 36 of the flexible seat panel 32 there is a
clearance Ps in a transverse direction between the tubular element
18 and the outer edge of the corresponding lateral tubular portion
36.
[0027] When a user is sitting on the flexible seat panel 32, the
flexible seat panel 32 assumes an arcuate shape as shown in FIGS. 3
and 5. The flexible seat panel 32 is elastically deformed to assume
the arcuate position. During the elastic deformation of the
flexible seat panel 32, the respective lateral tubular portions 36
move in a direction transverse to the respective tubular support
elements 18, by an amount equal to the respective transverse
clearance Ps. In the deformed position of the flexible seat panel
32, the clearance Ps between the outer edges of the tubular
portions 36 and the respective tubular support elements 18 is
canceled. When the ends of the lateral tubular portions 36 come
into contact with the respective tubular elements 18, a further
deformation of the flexible seat panel 32 is prevented. The
clearance Ps between the outer ends of the lateral tubular portions
36 and the respective tubular elements 18 determines the maximum
deformation Ds of the flexible seat panel 32.
[0028] FIGS. 6 and 7 show the detail of the relative movement of
the lateral tubular portions 36 with respect to the tubular seat
support elements 18, in the rest position and in the deformed
position of the flexible seat panel 32.
[0029] When the user rises from the chair 10, the flexible seat
panel 32 returns to the undeformed configuration as a result of its
elasticity. The lateral tubular portions 36 return to the position
illustrated in FIG. 6 and the lateral clearance Ps returns to the
initial value.
[0030] In the illustrated example, the clearance Ps of the lateral
tubular portions 36 is essentially constant along the longitudinal
axis of the respective tubular seat support element 18.
Consequently, the maximum deformation Ds of the flexible seat panel
32 is essentially constant along the central axis of the flexible
seat panel 32.
[0031] Alternatively, the clearance Ps, the ends of the lateral
tubular portions 36 and the respective tubular elements 18 could
vary along the axis of the respective tubular element 18, from a
minimum value level with the front end of the flexible seat panel
32, and a maximum value level with the rear end of the flexible
seat panel 32. In this way, in the conditions of use, the
deformation of the seat panel has a minimum value at the front edge
of the seat panel 32 and a maximum value at the rear edge of the
seat panel 32. Thus, in the deformed position, the central axis of
the seat panel 32 inclines backwards with respect to the undeformed
position. The backward inclination of the flexible seat panel 32
has a similar effect to that of chairs with seats hinged to the
fixed structure about a transverse axis.
[0032] With reference to FIGS. 8-11, the flexible backrest panel 34
has a lower edge 40 and an upper edge 42. In the example shown, the
lateral tubular portions 38 of the flexible backrest panel 34 have
lower ends aligned with the lower edge 40 and upper ends located
lower than the upper edge 42. Two notches 44 curving inwardly from
the respective outer edges of the flexible backrest panel 34 are
arranged immediately above the upper ends of the lateral tubular
portions 38. The flexible backrest panel is preferably provided
with vertical ribs 46 parallel to each other and protruding from
the front surface of the flexible backrest panel 34.
[0033] The lateral tubular portions 38 of the flexible backrest
panel 34 have transverse through-cuts 48 spaced apart in the
vertical direction. Each cut 48 forms an empty space in the wall of
the respective lateral tubular portion 38, contained in a plane
orthogonal to the longitudinal axis of the respective lateral
tubular portion 38. The through-cuts converge on respective
through-holes 50 formed along the inner edges of the respective
lateral tubular portions 38.
[0034] With reference to FIG. 10, in the rest condition, a
clearance Pb in a transverse direction is provided between the
outer edges of the lateral tubular portions 38 of the flexible
backrest panel 34 and the respective lateral tubular elements
20.
[0035] With reference to FIG. 9, the transverse clearance Pb of the
lateral tubular portions 38 varies along a vertical direction, from
a minimum value Pb' level with the lower edge 40 of the flexible
backrest panel 34, to a maximum value Pb'' level with the upper
edge of the lateral tubular portion 38.
[0036] In the rest condition (FIG. 10), the flexible backrest panel
has an arcuate shape. When a user leans back against the flexible
backrest panel, it is elastically deformed, as shown in FIG. 11.
The radius of curvature of the flexible backrest panel decreases.
During the elastic deformation of the flexible backrest panel 34,
the respective lateral tubular portions 38 move in a transverse
direction with respect to the respective tubular support elements
18, by an amount equal to the respective transverse clearance Pb.
In the deformed position of the flexible seat panel 32, the
clearance Pb between the outer edges of the tubular portions 38 and
the respective tubular support elements 20 is canceled, as shown in
FIG. 11. When the outer edges of the lateral tubular portions 38
come into contact with the respective tubular elements 20, a
further deformation of the flexible backrest panel 34 is prevented.
The clearance Pb between the outer edges of the lateral tubular
portions 38 and the respective tubular elements 20 determines the
maximum deformation of the flexible backrest panel 34. Given that
the clearance Pb varies in the vertical direction, the maximum
deformation of the flexible backrest panel 38 is greater for areas
closest to the upper edge 42 and lower for areas closest to the
lower edge 40. Consequently, in the deformed position, the backrest
inclines backwards with respect to the rest position by an angle a,
as shown in FIG. 2, where the continuous line indicates the rest
position and the dotted line indicates the deformed position of the
flexible backrest panel. The backward inclination of the backrest
has a similar effect to that of chairs with tilting backrests
articulated about a transverse axis. The through-cuts 48 serve to
enable a differentiated deformation of the various transversal
portions of the flexible backrest panel.
[0037] The flexible backrest panel is subject to an elastic return
force which tends to return it to the undeformed position. This
elastic force applies a thrust on the back of the user, in a manner
similar to the elastic mechanisms of chairs with tilting seats.
When the backward thrust applied by the user ceases, the backrest
returns to its rest position illustrated in FIG. 10.
[0038] Of course, without prejudice to the principle of the
invention, the details of construction and the embodiments can be
widely varied with respect to those described and illustrated,
without thereby departing from the scope of the invention as
defined by the claims that follow.
* * * * *