U.S. patent number 3,669,495 [Application Number 05/046,064] was granted by the patent office on 1972-06-13 for upholstered seating furniture.
Invention is credited to Edgar Von Rudgisch.
United States Patent |
3,669,495 |
Von Rudgisch |
June 13, 1972 |
UPHOLSTERED SEATING FURNITURE
Abstract
This invention relates to upholstered seating furniture which
comprises a unit of upholstered seating furniture which includes a
plurality of framing elements made from rigid foam and a plurality
of upholstering elements made from soft foam wherein the
improvement comprises at least one opening defined in at least some
of the framing elements, the surface of rigid foam around said
opening being in a compressed condition, a layer of semi-rigid foam
at least partly covering at least one framing element, said
semi-rigid foam serving as both a base for the seat and back and as
a resilient base for soft foam in other parts of said unit.
Inventors: |
Von Rudgisch; Edgar (5 Cologne
41, DT) |
Family
ID: |
25757512 |
Appl.
No.: |
05/046,064 |
Filed: |
June 15, 1970 |
Foreign Application Priority Data
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Jun 16, 1969 [DT] |
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P 19 30 583.0 |
Dec 5, 1969 [DT] |
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P 19 61 153.1 |
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Current U.S.
Class: |
297/451.11;
297/440.15; 297/DIG.2; 297/452.46; 297/440.22 |
Current CPC
Class: |
A47C
4/02 (20130101); A47C 4/028 (20130101); A47C
5/12 (20130101); Y10S 297/02 (20130101) |
Current International
Class: |
A47C
4/02 (20060101); A47C 5/00 (20060101); A47C
4/00 (20060101); A47C 5/12 (20060101); A47c
001/12 (); A47c 005/00 (); A47c 007/02 () |
Field of
Search: |
;297/44T,452T,DIG.2
;264/273 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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926,720 |
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May 1963 |
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GB |
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1,311,302 |
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Oct 1962 |
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FR |
|
Primary Examiner: Gilliam; Paul R.
Claims
I claim:
1. A unit of upholstered seating furniture which includes a
plurality of framing elements made from rigid foam and a plurality
of upholstering elements made from soft foam wherein the
improvement comprises:
at least one opening defined in at least some of the framing
elements,
the surface of rigid foam around said opening being in a compressed
condition,
a layer of semi-rigid foam at least partly covering at least one
framing element,
said semi-rigid foam serving as both a base for the seat and back
and as a resilient base for soft foam in other parts of said
unit,
said openings being provided with chamfered corners thereby
reducing undesirable stress concentrations,
at least a side of one of said opening and chamfered corners
associated therewith extending obliquely to a surface of said
framing elements, said base and back elements of said seat each
having abutting oblique surfaces forming a joint surface, and at
least one of said base and said back elements being tapered as to
depth.
2. A unit as defined in claim 1 wherein grooves are provided on the
adjacent surfaces of said rigid foam elements, the open ends of
said grooves abutting against one another and having cross section
which narrows towards their open sides, said semi-rigid foam
running into said grooves during foaming so as to form connection
elements with said rigid foam elements.
3. A unit as defined in claim 1 wherein a metal reinforcing profile
is incorporated in the rigid foam element forming the seat and a
metal reinforcing profile is incorporated in the rigid foam element
forming the back and wherein the reinforcing profiles of the seat
and the reinforcing profiles of the back include single flat bars,
said bars being aligned with said joint surfaces, and including
fastening means cooperating with said bars for securing said back
and seat together at said joint surfaces.
4. A unit as defined in claim 1 wherein the top surface of the
front end of the seat is provided with respective recesses in order
to provide the foamed-on layers with a greater thickness in the
region where the seated person rests his legs, said semi-rigid foam
layer having a substantially plane top surface extending across
said recesses, whereby the layers of semi-rigid foam and the layers
of soft foam being formed on in varying thicknesses according to
the softness and resilience required at the respective places.
5. A unit as defined in claim 1 wherein the respective layers of
semi-rigid foam foamed onto the seat and the back are provided with
holes for the purpose of ventilation.
6. A unit as defined in claim 1 wherein a layer of soft foam is
foamed onto the layer of semi-rigid foam on the back, the soft foam
flowing through the holes during the foaming operation and entering
the interior cavity in the frame-like back where it forms a core of
soft foam.
7. A unit as defined in claim 1 including upholstery material
superimposed on said soft foam and wherein nailing grooves are
provided in the back and the seat, and wherein the center of the
bottom region of the lateral narrow sides of the back is provided
with recesses, the ends of the covering material, drawn onto these
parts being inserted into the said grooves and recesses and secured
therein.
8. A unit as defined in claim 1 wherein the top of the back is
provided with narrow projections, said semi-rigid foam layer
extending over said top of the back, whereby said projections
improve the hold of the layer of semi-rigid foam.
9. A unit as defined in claim 1 including side panels, means
joining said side panels along opposite sides of said seat element
and said back element, said side panels having grooves provided in
the top of the side panels and along the outsides of said side
panels at a short distance below the top edge thereof, and in which
an arm pad of semi-rigid foam said foam extending into said grooves
to form tongues serving to secure the arm rest to the side
panel.
10. A unit as defined in claim 1 wherein said back frame element of
rigid foam is in the shape of an open ended U, the height of the U
being lower than the height of the entire back, a tubular resilient
element being inserted into the top end of the arms of the U to
form a closed frame, said semi-rigid foam layer enclosing said
resilient element and said back element to form a complete, closed
back.
Description
The present invention relates to upholstered seating furniture such
as armchairs, sofas, benches or the like. In conventional
technology, seating furniture comprises a frame made from wood, and
upholstery made from natural or synthetic materials, which are
covered with a covering material such as a textile fabric, a
plastics material or the like.
It is known to manufacture upholstered seating furniture from
synthetic material. For this purpose, the seat frame is made from
rigid foam support elements and the upholstery from a soft foam.
Swiss Pat. Specification No. 464,509 discloses foam raw materials
and describes how foams of different hardness can be foamed
individually and how they may also be foamed one on top of the
other. The physical properties of the plastics material foam used,
such as hardness, softness, and resilience, may be selected so that
the elements made from plastics material foam perform a framing or
upholstering function.
Plastics material foams having the necessary stable shape,
resistance to ageing, and permanent resilience required for this
purpose are available. Such plastics material foams include foams
based on polyurethane, polystyrene, polyvinyl chloride, urea
formaldehyde, phenol formaldehyde, and latex etc.
In recent times, increasing demands have been made in the
upholstered furniture industry with respect to reducing the
manufacturing times, simplifying the manufacturing work, and
designing seating furniture so that a large number of different
types of furniture may be constructed from only a few basic
elements. A large number of designs are possible in the case of an
upholstered armchair for example. The side panels or the back, for
example, have to be of different construction according to the
style in which the armchair is to be constructed, while the seat
for example, remains the same.
The present invention seeks to simplify the manufacture of such
upholstered seating furniture both with regard to the manufacture
of the separate framing and upholstery elements and the assembly
thereof, and also with regard to storage by the manufacturer.
In accordance with the present invention, the basic prerequisite is
for the framing elements, made from rigid foam, to be in the form
of prefabricated parts such as seats, backs, side panels, scrolls,
head rests, wings, etc. which may be assembled to form seating
furniture. Thus, the framing elements are manufactured in the form
of basic units of different shapes according to the style of the
seating furniture required which are then assembled in any desired
combination to form the seat.
In conventional technology, straps, spring cores, steel springs,
upholstery made from synthetic or natural material, for example,
are used for seating furniture springing. In accordance with one
aspect of the present invention, the seat bolsters or cushions are
made exclusively from plastics material foams in a manner known per
se. In accordance with another aspect of the invention, layers of
semi-rigid foam are foamed onto the framing elements which are made
from rigid foam.
A feature of this aspect of the invention is that the foamed
semi-rigid foam serves to connect the rigid foam elements in
addition to providing the upholstery. From the viewpoint of
manufacturing technique, this has the great advantage that the
foaming operation not only serves to form the upholstery, but at
the same time replaces a connecting operation. It is not essential
for the connection to be rigid, since it may be somewhat elastic
and resilient, thus providing a certain degree of flexibility in
the connection between the elements made from rigid foam.
In accordance with a further aspect of the invention, one way of
connecting the rigid foam elements together is by providing the
abutting surfaces of the rigid foam elements with grooves the open
ends of which are adjacent to each other, the semi-rigid foam
entering these grooves during the foaming operation, thus forming
connection elements.
Advantageously, the cross section of these grooves narrows towards
their open sides. The grooves in two rigid foam elements to be
connected together are arranged so that their narrow sides lie
adjacent. The semi-rigid foam enters the grooves and forms a
connection element which corresponds to the shape of the two
adjacent grooves and is therefore wider towards the outside. Thus,
the connection element is retained in the two grooves, which are
substantially dovetail-shaped, and cannot slip out.
In a preferred embodiment, the grooves have a circular cross
sectional shape, a segment being cut from the open side of the
circle thus providing the narrowing. The grooves are provided by
inserting a core or an insert into the mould in which the rigid
foam element is foamed. The cores or inserts may be or particularly
simple construction if, in accordance with the invention, the
grooves have a circular configuration, a segment being cut from one
side thereof. The core or the insert is then in the form of a
simple cylindrical tubular piece flattened on one side.
In accordance with the invention, the semi-rigid foam is foamed
onto the rigid foam elements so as to form a resilient or
cushioning, connecting element. To ensure that the semi-rigid foam
is bonded unreleasably to the hard foam elements, and in accordance
with the present invention, the outer surfaces of the rigid foam
elements are provided with grooves into which the semi-rigid foam
runs when it is being foamed onto the rigid foam elements, thus
securing the former to the latter.
The strength of the rigid foam elements depends upon the density of
the foam materials. This density is dependent upon the quantity of
raw material used per unit of volume. The density and thus the
strength of the rigid foam element is increased if the same
quantity of raw material is used for a smaller volume. In
accordance with the invention, the rigid foam elements are provided
with openings in order to utilize this advantageous effect.
During the foaming operation, the surface of the rigid foam is
compressed on the surfaces adjacent the openings and forms the
so-called integral foam. The strength and thus the moment of
resistance of the integral foam is greater than the strength and
the moment of resistance of the rigid foam in the other regions of
the rigid foam elements. This is due to the fact that the
propellent forms the foam from the center of the mould and propels
it outwardly. The foaming pressure attains its maximum on the
outside, i.e. on the outsides or surfaces of the element. The
separate pores in the foam are greatly compressed, and the
resulting density can be ten times the density in the core or in
the center of the element. Thus, by virtue of the openings
providing in accordance with the invention, additional surfaces are
provided artificially on which the integral foam is formed.
However, the openings have a further advantage in addition to
leading to a higher surface and thus to integral foam of greater
strength. The same quantity of raw material is distributed to a
smaller volume when openings are provided, since the openings
remain free. Thus, the same quantity of raw material is compressed
to a smaller volume. Thus, the density is increased. The strength,
which is proportional to the density, also increases.
The greater density and the greater strength provided by the
openings can attain values which are not required. This leads to a
saving of raw material. The smaller volume can be completely filled
by a smaller volume of raw material. This leads to a considerable
reduction in cost, since the raw material is expensive.
The following numerical example explains how a higher density and
thus a higher strength may be obtained with a smaller quantity of
raw material.
Let is be assumed that a volume of 15 liters is to be filled with
rigid foam. A density of 130 gr/cm.sup.3 is required. This requires
1.950 kg of material.
In accordance with the invention, an opening having a volume of 5
liters is provided. A residual volume of 10 liters has to be
filled. If the same amount of 1.95 kg of material is introduced,
this leads to a density of 195 gr/cm.sup.3. This means that the
density has increased by one and a half times. The strength has
also increased proportionally.
An input of 1.3 kg of material is adequate if the original average
density of 130 gr/cm.sup.3 is sufficient, thus saving 0.65 kg of
raw material.
The strength has increased considerably, despite the same value for
the average density. As already mentioned, the density of a foam
element varies from the inside towards the outside. By providing an
opening in the center of the foam element, the less dense and thus
structurally weak center is removed from the element. Furthermore,
additional surfaces are provided at the opening and lead to a
particularly hard integral foam. The hardness of the integral foam
can, for example, be up to six times the hardness of the foam in
the center of the element.
By virtue of the invention, advantageous use is made of these
effects of the foaming operation which lead to a density which
increases from the inside to the outside, and thus to increased
strength, with reduced expenditure on material. Furthermore, the
surfaces are increased, thus enhancing the skin formation.
In an advantageous embodiment of the invention, the corners of the
openings are chamfered or extend obliquely. This simplifies the
moulding. At the same time concentrations of stress, which occur in
sharp corners, are considerably reduced or obviated.
Furthermore, in accordance with the invention, the walls of the
openings extend obliquely. This increases the surface and thus the
skin formation and strength. In the same manner, better adaptation
to local stress and to the nature of the stress within the rigid
foam element can be provided.
In a further embodiment of the invention, and for the same purpose,
the openings do not have parallel walls, but are of irregular shape
with raised ends.
Thus, the openings reduce the consumption of foam material,
although greater strength is obtained since the material is
compressed to a greater extent in the remaining portion and the
skin formation is increased.
In comparison to wood, which is traditionally used for the framing
elements of seats, the plastics material foam is advantageous in
that it is easy to shape. The plastics material foam assumes any
shape prescribed by a specific shape of the mould in which the
plastics material is foamed. The invention utilizes this
possibility and provides shapes which simplify the assembly of the
separate rigid foam elements to form the finished seating furniture
and which increase the strength thereof.
In an advantageous embodiment of the invention, the abutting
surfaces of the seat and back, or of the seat and the screen are
stepped by forming step-like shoulders which interengage. Of
course, the step-like shoulders may also be provided between other
elements such as the seat and the side panels.
In a different additional type of connection, a threaded bolt is
inserted into one of the rigid foam elements which are to be
connected to one another. The threaded bolt projects from the
element and is screwed into a threaded plate which is inserted into
the other element.
Furthermore, the abutting surfaces of the rigid foam elements to be
connected to one another are provided with bores which extend at
right angles to the contact surfaces and which serve for inserting
connection elements such as threaded bolts. These bores are formed
from the outset by appropriate inserts or cores in the mould in
which the rigid foam element is foamed.
It may be necessary to provide a rigid foam element with additional
reinforcement. For this purpose, and in accordance with the
invention, a metal reinforcing bar section is incorporated in the
relevant rigid foam element.
Such a reinforcing bar section is incorporated in the seat for
example.
In an advantageous embodiment, such a reinforcing bar section is in
the form of an angle iron. Such an angle iron is arranged on each
side of the seat. The angle iron extends along the side and along
the rear edge of the seat. The angle iron is provided with bores
which are in registry with the bores in the rigid foam element and
which serve for inserting connection elements, and with bores into
which the foam runs for securing purposes.
In accordance with the invention, one limb of the angle iron
extends horizontally and is provided with plain or threaded bores
for receiving threaded bolts holding the feet. The vertical limbs
of the angle iron may be provided with threaded bores which serve
for receiving threaded bolts by which the side parts and the back
are mounted.
The angle iron located in the seat is bent to form an L-shape the
longer limb of which extends along the side of the seat and the
shorter limb of which is directed inwardly and extends along the
rear edge of the seat.
If the back is also to be reinforced, a metal reinforcing bar
section is incorporated in the rigid foam element forming the
back.
Advantageously, this reinforcing bar section is also in the form of
an angle iron, and such an angle iron is arranged on each side of
the back.
In accordance with the invention, the angle irons incorporated in
the back are also provided with bores which are in alignment with
the bores in the seat and serve for receiving connection elements
such as threaded bolts. However, further bores are provided and
serve for inserting bolts which project from the side panels. In
accordance with the invention, these latter bores are in the form
of slotted holes.
Advantageously, the reinforcing bar profiles incorporated in the
back are also bent to form an L the longer limb of which extends
along the side of the back and the shorter limb of which is
directed inwardly and extends along the underside of the back.
The limbs extending along the underside of the back receive the
connection elements, for example the bolts, which extend from the
seat and which serve to connect the seat to the back.
Considerable savings in cost can be achieved by simplifying a
single part which is mass-produced in the same manner as the
upholstered furniture constructed in accordance with the invention.
This applies, for example, to the reinforcing bar sections which at
the same time serve as metal fittings and securing elements for the
threaded, screw, and inserting elements. These bar sections are
arranged on both sides of the back. Further bar sections are
arranged in the seat where they serve as reinforcements. The bar
section arranged at the rear in the seat also forms the
counter-piece for the bar sections arranged in the back and
receives screws etc. The bar sections arranged in the seat are
provided with further threads into which the feet are screwed.
In accordance with the invention, these bar sections and their
associated threaded, screw, and inserting elements should be
constructed so that they constitute mass-produced articles and can
be manufactured at low cost. In accordance with the invention, this
is achieved in that the bar sections are in the form of simple flat
bars on which the threaded, screw, and/or inserting elements are
secured.
The flat bars arranged in the sides of the back have hooks secured
thereto by welding for example, the hooks project from the sides of
the back, inserting bushes are arranged in the side panels and are
provided with slots which are located opposite the insides of the
side panels, the hooks and the inserting bushes being located
relative to each other such that they are located at the same
height when the panels are in their final positions.
The inserting bushes are in the form of sleeves provided with a
cavity. Vanes extend from the outside of the sleeves in order to
anchor the sleeves in the foam material.
In accordance with the invention, the hooks mounted on the flat
bars on the back are provided with a sloping surface which engages
behind the surface of the slots when the hooks are inserted into
the inserting bushes.
If the upholstered furniture is provided with a screen, i.e. a bar
or moulding mounted on the front narrow side of the seat, and side
panels, smooth inserting bushes and threaded bushes in alignment
with one another are formed in the seat, in the screen, and in the
side panels, and bores pass through the seat, the screen, and the
side panels in alignment with the bushes, screws being inserted or
screwed into the bushes.
In accordance with the invention, to secure a head rest to the top
of the back, hooks are arranged in the top of the back and
partially project therefrom, inserting bushes co-operating with
these hooks are arranged in the head rest, the head rest being
slipped on to the hooks from one side and being held by side panels
slipped over its ends.
To secure the feet, and in accordance with the invention, threaded
bushes are let into the underside of the seat, the feet being
screwable into the bushes. The sides of the bushes may be provided
with vanes for the purpose of securing the bushes in the foam
material.
To connect the back to the seat in a simple manner, the flat bars
let into the underside of the back and into the rear of the seat
are located at the same height and have bores which are in
alignment with each other. The back and the seat are connected to
one another by a screw inserted through the bores and secured by a
nut.
In accordance with the invention, the back is especially provided
with a layer of soft foam, since the back of an armchair must be
softer or have a greater cushioning effect than the seat. The
softness or cushioning effect must be greater at the top narrow
side of the back than on its remaining surface, since this is where
the seated person rests his head. In order to obtain the desired
softness or cushioning effect at the top narrow side, and in
accordance with the invention, the top narrow side of the back
(i.e. the rigid foam element) is provided with a recess, so that
the expanded layers of semi-rigid foam and soft foam attain a
greater thickness at this position.
The softness and cushioning effect of the seat should be
particularly great at the front edge. In accordance with the
invention, this is achieved in that the front end of the seat and
the top of the screen are each provided with a recess so that the
foamed layers are provided with a greater thickness in the region
in contact with the legs of the seated person.
There are places on the chair, sofa or the like where the softness
and cushioning effect, i.e. the depth to which the surface may be
depressed by the same application of force, should vary. The
invention can readily fulfil these requirements. It is necessary
only to expand the semi-rigid foam layers and the soft foam layers
to different thicknesses in accordance with the desired softness
and cushioning effect at the respective places. The different
heights of the foam layers are obtained by specially designing the
respective moulds.
The back and the seat of a chair, or the like, must be ventilated
so that the seated person does not perspire. For this purpose, and
in accordance with the invention, the semi-rigid foam layer or the
soft foam layer foamed onto the seat or the back is provided with
holes. The seat and the back move forwards or backwards to a
greater or lesser extent at each movement of the seated person, so
that air can flow through the holes.
Due the lesser density of soft foam, the quantity of raw material
required for the soft foam per unit of volume is less than in the
case of rigid foam. Accordingly, the cost of soft foam per unit of
volume is less than in the case of semi-rigid or rigid foam. Thus,
advantageously, areas which are not subject to static stress, or
which are subject to only slight static stress, are padded with
soft foam. Such slight static stress occurs in the center region of
the back. Thus, adequate rigidity is provided if this region is
filled with soft foam.
It has already been mentioned that a layer of soft foam is foamed
onto the layer of semi-rigid foam on the back. In accordance with
the invention, this soft foam passes through the holes in the layer
of semi-rigid foam on the back during the foaming operation and
runs into the interior space in the frame-like back where it forms
a core of soft foam. It is also necessary to fill the back in order
to provide a continuous, smooth surface on the rear of the back for
the covering material.
In accordance with the invention, the foam layers on the back, the
seat, the side panels, the screen, the head rest, etc. are covered
with a covering material such as a textile fabric, a plastics
material, etc.
In an advantageous embodiment of the invention, the back, the seat,
the side panels, the screen, the head rest etc. are provided with
nailing grooves into which the ends of the covering material are
inserted and secured. Advantageously, the nailing grooves are
arranged at places which are covered by another part during
assembly. The nailing grooves are located in the contact surfaces
of the seat and the back for example.
Advantageously, the back is covered by a covering material which is
sewn in the form of an envelope which is drawn over the back. This
envelope is open at one end and is drawn onto the back by this open
end. In accordance with the invention, the lateral narrow sides in
the center of the lower region of the back are provided with
recesses into which the bottom open ends of the envelope, made from
the covering material, are inserted. These recesses are concealed
by the side panels when the piece of furniture is in the assembled
state.
Advantageously, the slotted holes which receive the inserting bolts
projecting from the side panels are located within these
recesses.
The recesses have an additional purpose. Some backs are of
wedge-shaped construction, i.e. their thickness increases from the
top to the bottom. The bottom and thus wider regions of the narrow
sides of such as backs are not covered with covering material,
since these regions are concealed by the side panels. Thus,
covering material can be saved. If the back is covered with an
envelope of covering material, the envelope will be left open in
the bottom region of the narrow sides of the back in order to save
material, since these places are also concealed by the sides. These
open ends of the envelope are accommodated and secured in the
recesses.
In order satisfactorily to connect the seat to the back, the
contact areas of the seat and the back must be as large as
possible. In accordance with the invention, the abutting faces of
the back and the seat are oblique and have a relatively large
surface. These sloping surfaces may readily be obtained by the
appropriate configuration of foam moulds. Different angles between
the seat and the back are obtained by varying the angle of these
oblique faces relative to the horizontal.
It has already been mentioned that the seat, sofa, or the like
should be particularly soft at specific places.
By way of example, and in accordance with the invention, the layer
of semi-rigid foam which is foamed onto the side panels is
thickened in the region in which the seated person rests his hands,
so that this thickened portion forms a soft, resilient hand
rest.
In accordance with the invention, the top narrow side of the back
is provided, particularly at the ends, with narrow projections
which serve to improve the hold of the foam-on layer of semi-rigid
foam. If these projections are provided only at the ends, the
center of the foamed-on layer is at the same time provided with a
greater depth, so that the softness is increased in this region.
Thus, the back is rendered softer at the place where a seated
person rests his head.
A similar softness is also required for the tops of the narrow
sides where a seated person rests his arms. To meet this
requirement, and in accordance with the invention, the top narrow
sides and the outsides of the side panels are provided with grooves
which extend along the top edge at a short distance below the
latter, and an arm pad of semi-rigid and/or soft foam is foamed
onto the top barrow side and somewhat below on a top edge region of
the side face, the foam having run into the grooves during the
foaming-on operation for the purpose of anchoring the arm pad by
forming tongues. A tongue and groove connection is produced, the
tongues being integrally formed with the arm pad.
It has already been mentioned that the rigid foam elements are
provided with openings at the places less subject to static
stresses, in order to save material and in order to obtain greater
rigidity by increased compression of the material at the other
places.
Thus, in an advantageous development of the side panels, the
opening provided in the side panel is divided into two openings
which are located one behind the other and which are separated from
one another by a rib or bridge.
In an alternative side panel, the opening provided therein is
divided into two smaller openings which are located one beside the
other and which merge into one another, the outer opening being
larger and the inner opening being smaller.
In accordance with the invention, the back has a larger opening
which is of substantially square shape and which is located in the
top region of the back, two further smaller openings being provided
below this larger opening.
In an advantageous design of these two smaller openings, their top,
outer corners are raised or provided with projections, thus
achieving the object of designing the openings so as to have the
largest possible area, thus saving expensive raw material.
Experiments have shown that the openings lead to greater rigidity
despite the lower expenditure on material. This results from the
fact that the smaller quantity of material is compressed to a
greater extent in the remaining smaller volume, greater compression
automatically leading to greater rigidity.
There are various ways of shaping and mounting the wings. The
invention proposes an embodiment in which the wings cover the sides
of the top region of the back and the ends of the head rest mounted
on the back, the semi-rigid foam forming connection elements by
running into the grooves which have already been mentioned and
which are provided in the abutting faces of the back, headrest and
wings.
With regard to the upholstery, the back requires a different
construction from the seat for example. The back should be softer
than the seat for example. Furthermore, the entire surface of the
back is a visible surface, while only the top of the seat is a
visible surface or can be touched. Thus, in accordance with the
invention, the layer of soft foam foamed onto the back
advantageously surrounds the inside, the top and the outside of the
back.
The invention provides different shapes for the screen. In the
first embodiment, the screen extends only along the front side of
the seat.
In a second embodiment, the screen extends along the front side of
the seat, its ends being angled rearwardly, and partially surrounds
the sides of the seat. This embodiment is used if the side panels
do not reach to the front edge of the seat, but are set back
towards the rear.
In a modification of this latter embodiment, the rearwardly angled
ends of the screen taper in the form of sloping faces which overlap
and abut against corresponding sloping faces on the front ends of
the side panels.
There are some styles of furniture which require the screen to be
extended downwardly almost to the ground. In this embodiment, it
may be advantageous for the screen to be used at the same time for
securing the front feet which are generally secured below the seat.
In accordance with the invention, this is achieved by extending the
screen downwardly and providing it with a rearwardly angled bottom
strip which engages below the front edge of the seat, feet such as
low spherical rollers being secured on the underside of the bottom
strip.
In the case of a chair, it may be necessary for the back to be of
greatly resilient construction, so that it bends or tilts
backwardly if the person sitting in the chair bends his back
towards the rear. To meet such a requirement, and in accordance
with the invention, the frame-like element of rigid foam forming
the back is in the shape of a U open at the top, the height of the
U being lower than the total height of the back, a tubular
resilient element, which completes the upwardly open U to form a
closed frame, being inserted into the top ends of the arms of the
U, and the resilient element being covered with semi-rigid and/or
soft foam layers to form a complete closed back. The rigid
construction of the back comprising semi-rigid foam is thus
partially replaced by the resilient element, so that a highly
flexible or resilient back is produced.
In accordance with the invention, the resilient element comprises
individual tubular pieces which are spaced one behind the other and
which are covered with a soft foam which holds them together.
In accordance with the invention, these tubular pieces are provided
with bores through which the foam runs into the tubular pieces.
Thus, the tubular pieces are held together by the foam which has
penetrated into them and which extends in one piece in a
sausage-shaped manner through all the tubular pieces located one
behind the other, and by the foam surrounding them.
The bores through which the foam runs into the tubular pieces are
distributed along the tubular pieces in the longitudinal direction
thereof. They pass through the walls of the tubular pieces at right
angles thereto and are located opposite one another in pairs.
Advantageously, pairs of bores located behind each other are
staggered by 90.degree. pieces, determines to extent
The distance between the ends of the tubular pieces, or the gap
between the tubular pieces, determines the extent to which the
resilient element can be deflected. The spring action is terminated
when the tubular pieces close the gap and their ends abut against
one another. The soft foam located in the gap is then compressed at
one side and expanded at the other side.
In the basic shape, the gaps between the ends of the tubular pieces
have parallel sides. The width of the gaps then determines the
spring action which may be attained.
In a modified embodiment, the gaps between the ends of the tubular
pieces are wedge-shaped gaps. This means that the resilient element
can be deflected to different degrees towards both sides. The
tubular pieces can move closer together at the side at which the
gaps are wider, thus resulting in a considerable spring action.
When pressure is exerted in the opposite direction, the ends of the
tubular pieces immediately abut against each other due to the
slight width of the gaps, so that the spring action is slight in
this direction.
It is obvious that this resilient element of the invention may also
be used in furniture other than seating furniture. For example the
resilient element may be used in mattresses, cushions, floor mats
for gymnasts, etc.
The invention will now be further described by way of example with
reference to the accompanying drawings, in which:
FIG. 1 is an exploded illustration of a plurality of rigid foam
parts which form the frame of an upholstered chair,
FIG. 2 is a exploded illustration similar to FIG. 1, in which the
rigid foam parts are covered with semi-rigid foam,
FIG. 3 is an exploded illustration similar to FIG. 1, of a
different embodiment which includes an arm rest,
FIG. 4 is a rear elevational view of the back panel of the chair of
FIG. 3,
FIG. 5 is a section through the bottom bar of the back panel taken
on the lines 5-- 5 of FIG. 4;
FIG. 6 is a section through the side panel, taken on the line 6-- 6
of FIG. 3,
FIG. 7 is a perspective illustration of one form of back panel
having a head rest and a wing,
FIG. 8 is a perspective illustration of a finished upholstered
chain manufactured in accordance with the invention,
FIG. 9 is a section through the top bar of the back panel and
through the head rest, taken on the lines 9-- 9 of FIG. 7,
FIG. 10 is a section corresponding to FIG. 9, but with semi-rigid
foam foamed onto the rigid foam frame elements,
FIG. 11 is a section corresponding to FIG. 10), in which soft foam
has additionally been foamed on,
FIG. 12 is a section through the front bar of the seat and an
attached scroll,
FIG. 13 is a section similar to FIG. 12, showing an alternative
scroll,
FIG. 14 is a section similar to FIG. 12, showing a further
alternative scroll,
FIG. 15 is a plan view of the scroll illustrated in FIG, 12,
FIG. 16 is a plan view similar to FIG 15 showing a different
scroll,
FIG. 17 is a plan view similar to FIG. 15 showing another
scroll,
FIG. 18 is a fragmentary perspective view of the back panel and
illustrates a preferred form of wing,
FIG. 19 is an ilustration similar to FIg. 18, showing an
alternative wing,
FIG. 20 is a longitudinal section through an upholstered armchair
manufactured in accordance with the invention,
FIG. 21 is a fragmentary plan view of the upholstered armchair
illustrated in FIG. 20, showing especially the metal reinforcing
profiles incorporated in the seat and the back panel,
FIG. 22 is a section through an alternative back panel,
FIG. 23 is a front elevation of the back panel illustrated in FIG.
22,
FIG. 24 is a section through an alternative seat,
FIG. 25 is a plan view of the seat illustrated in FIG. 24,
FIG. 26 is a vertical section through the connection between the
seat and the back panel,
FIG. 27 is a horizontal section through the connection between the
seat, side panel, and scroll,
FIG. 28 is a section through the threaded bush into which the feet
are screwed,
FIG. 29 is a plan view of the bush,
FIG. 30 is a section through a smooth inserting bush,
FIG. 31 is a fragmentary view of the back panel particularly
showing the inserting elements for securing the side panel,
FIG. 32 is a fragmentary section through a side panel, particularly
showing the inserting element for connecting the side panel to the
back panel,
FIG. 33 is a side elevation of an inserting bush,
FIG. 34 is a plan view of the bush of FIG. 33,
FIG. 35 is a diagrammatic illustration of the manner in which the
head rest is secured to the back panel,
FIG. 36 is a perspective illustration of a seat and of a back
panel, the frame of the back being formed partially by the
resilient element constructed in accordance with the invention,
FIG. 37 is a section through a part of the resilient element
constructed in accordance with the invention,
FIG. 38 is a section similar to FIG. 37, in which the resilient
element is illustrated in a deflected state,
FIG. 39 is a schematic, perspective illustration of a form of the
resilient element which, by virtue of wedge-shaped gaps, is
provided with a spring action dependent upon direction,
FIG. 40 is a section through a part of the resilient element
illustrated in FIG.39,
FIG. 41 is a section similar to FIG. 40, in which the wedge-shaped
gap is closed, or the resilient element deflected,
FIG. 42 is a section taken on the line 42--42 of FIG. 40,
FIG. 43 is a section similar to FIG. 40, in which the wedge-shaped
gap is narrower, and
FIG. 44 is a section through the tubular element illustrated in
FIG. 43, the tubular element being in the deflected state.
FIG. 1 shows a frame-shaped back panel 42, a frame-shaped seat 44,
a side panel 46, and a screen 48. These parts are made from rigid
foam and constitute the framing elements of an upholstered
armchair. An opening 50 is formed in the back panel 42, an opening
52 is formed in the seat 44, and two openings 54 are provided in
the side panels 46. Some corners of each opening are chamfered at
56. This reduces undesirable concentrations of stress and notch
stresses. A foam groove 58 extends along the top edge of the back
panel 42. A further foam groove 60 surrounds the opening 50. The
bottom end of the back panel 42 is provided with a large oblique
surface 62 by which the back panel 42 abuts against the seat 44. A
further foam groove 64 extends along the top edge of the oblique
surface 62 and an indentation 66 extends along the bottom edge of
the oblique surface 62. The indentation 66 serves to improve the
connection of the back panel 42 to the seat 44. The side faces of
the back 42 are provided with recesses 68 into which the bottom
ends of the covering material are inserted. The slotted holes 70,
into which the side panels 46 are fitted, are also located in the
recesses 68. Bores 72 are provided in the back 42, in the seat 44,
and in the side panels 46. Connection elements such as threaded
bolts or screws are inserted through these bores.
The front side of the seat 44 has a step-like shoulder 82. The rear
of the seat 44 is provided with an oblique surface 84 which abuts
against the oblique surface 62 of the back panel 42 when the chair
is in its assembled state. The rear of the seat 44 is also provided
with a projection 86 which fits into the indentation 66 in the back
panel 42. A foam groove 78 extends around the opening 52 in the
seat 44. The front bar of the seat 44 is also provided with a
recess 80. The semi-rigid foam material subsequently runs into this
recess to provide extra thickness. Thus, at this place, the seat 44
is softer. A recess 74 intended for the same purpose is also
provided on the top of the back 42. The top of the back is also
provided with two projections 76 which serve to improve the hold of
the layer of semi-rigid foam to be foamed on.
The top of the side panel 46 is provided with grooves 88. The
semi-rigid foam subsequently runs into these grooves and is held
therein. The side panel is also provided with a bolt 90 which is
inserted into the slotted hole 70 in the back 42. Nailing grooves
92 for nailing or stapling the covering material are provided in
the side panel 46.
The scroll 48 is provided with a projection 94 which abuts against
the step-shaped shoulder 82 on the seat 44. The scroll 48 is also
provided with a recess 96 which is filled with semi-rigid foam,
thus providing the desired soft support for the legs of the person
seated in the armchair.
FIG. 2 shows the rigid foam elements, illustrated in FIG. 1, having
the layers of semi-rigid foam foamed thereon. The inside of the
back panel 42 is coated with a layer 98 of semi-rigid foam. The
seat 44 is covered with a layer 100 of semi-rigid foam which at the
same time forms the entire area of the seat. The scroll 48 is
coated with a layer 102 of semi-rigid foam. The side panel 46 is
covered by a layer 104 of semi-rigid foam. The front of the layer
104 has a thickened portion 106, thus providing a soft support for
the hands. The layers 98 and 100 of semi-rigid foam are provided
with holes 108. This ventilates the back and the seat and prevents
a person sitting in the armchair from perspiring. FIG. 2 also shows
how the layers of semi-rigid foam have filled the foam grooves 58,
how they have covered the projections 76, how they have filled the
recesses 80 and 96, and how they have run into the grooves 88.
FIG. 3 shows a head rest 110 and two wings 112 which are not shown
in FIG. 1. The faces of the back panel 42, of the head rest 110,
and of the wings 112, which abut against each other when the chair
is assembled, are provided with grooves 88 into which the
semi-rigid foam runs for the purpose of interconnecting these
parts. FIG. 3 also shows the reinforcing profiles 114 which are
incorporated in the back panel 42. The reinforcing profiles 114 are
provided with slotted holes 116 which are in alignment with the
holes 70. The reinforcing profiles 114 are also provided with bores
118 which are in alignment with the holes 72 in the back panel.
In this embodiment of the seat 44, the front bar is provided with
locating bores 120. A threaded bolt 122 is also provided. The
threaded bolt 122 is associated with a bolt (FIG. 21). The locating
bores 120 receive locating pegs 124 which are formed on the scroll
48. The threaded bolt 122 is screwed into a threaded plate 126
which is incorporated into the screen 48. Similar threaded plates
128 are incorporated in the side panels 46.
FIG. 3 also shows an arm rest 130 which is made from semi-rigid
and/or soft foam. It is provided with tongues or beads 132 which
are located in the longitudinal grooves 88 in the side panel 46
when the chair is assembled. The arm rest 130 is foamed onto the
side panel 46 in a mould, the tongues or beads 132 being formed in
the grooves 88.
FIG. 4 is a rear view of the back panel 42. Two smaller openings
134 are provided below the large, square opening 50. The top outer
corners of the openings 134 are extending upwardly and form
projections 136. The projections 136 extend parallel to the
chamfers 56 of the opening 50. The projections or upwardly extended
ends 136 illustrate the object of the invention, which is to
provide the rigid-foam elements with the largest possible number of
openings in order to save material or to compress the same or
smaller quantities of material to a smaller volume.
FIG. 5 shows the bottom bar of the back, as illustrated in FIG. 4.
A nailing groove 65 is also shown, into which one end of the
covering material is fitted.
FIG. 6 shows a section through the side panel 46 illustrated in
FIG. 3. The side panel 46 is provided with two openings 138 and
140. These two openings are located laterally adjacent to each
other. The inner opening 140 is smaller, since the inside of the
side panel, where the seated person is located, should be closed as
far as possible. However, the opening 138 on the outside of the
side panel can be larger.
FIG. 7 is a perspective illustration of a back 42 having a head
rest 110 and a wing 112. The special purpose of this Figure is to
show, in conjunction with the sections shown in FIGS. 9 to 11, how
the head rest 110 and the wing 112 are secured to the back panel
42. When the layer 98 of semi-rigid foam is foamed onto the back
panel 42 (see also FIG. 2) the semi-rigid foam runs into the
grooves 88. This is shown in FIG. 10. In conformity with the
configuration of the abutting grooves 88 in the back panel 42, in
the head rest 110, and in the wing 112 (See FIG. 7), the semi-rigid
foam in the grooves assumes the shape of a rib which has a
necked-down center region and which securely connects the two rigid
foam elements. Since the semi-rigid foam has a certain elasticity,
the head rest 110 and the wings 112 are resiliently connected to
the back panel, so that they yield slightly when pressed.
FIG. 11 shows a layer 142 of soft foam which is foamed across the
entire back panel. The soft foam has passed through the holes 108
into the opening 50 in the back where it forms a core of soft foam
or filling mass.
In the sections shown in FIGS. 9 to 11, and in other sectional
drawings, the rigid foam elements are indicated by oblique shading,
while the semi-rigid foam is cross-shaded, and the soft foam is
shown by dotting.
FIGS. 12 to 14 show various scrolls 48. The scroll 48 abuts only
against the front side of the seat and is provided with locating
pegs 124 illustrated in FIG. 3. The rear of the scroll 48
illustrated in FIG. 13 has a stepped configuration as is
illustrated in FIG. 1 and which ensures the the scroll engages
better with the front bar of the seat 44. The bottom of the scroll
48 illustrated in FIG. 14 is extended downwardly and angled
rearwardly, thus producing a bottom strip 144 which is located
below the front bar of the seat. Spherical rollers 146 are secured
below the bottom strip 144.
FIGS. 15 to 17 are plan views of various scrolls 48. The rear of
the scroll 48 abuts against the front of the seat and against the
front ends of the side panels 46. The scroll 48 illustrated in FIG.
16 is angled rearwardly. In this embodiment, the two side panels 46
are set back or shorter. The angled ends 148 of the scroll 48 abut
against the front ends of the side panels 46.
The embodiment illustrated in FIG. 17 is based on the embodiment
illustrated in FIG. 16. The side panels 46 extends further towards
the front. The side panel 46 and the scroll 48 abut against each
other along the sloping faces 150.
FIGS. 18 and 19 illustrate various wings 112. FIG. 18 illustrates a
wing which is wider at the top than at the bottom and whose outside
is of sloping configuration. FIG. 19 illustrates an elongate wing
whose longer sides extend vertically.
The unit-composed system of the present invention is shown
particularly clearly in FIGS. 12 to 19. Irrespective of the
individual appearance of the various elements, they can be
assembled in an optional manner and are always interconnected in
accordance with the same system.
FIG. 20 is a section through the center of an upholstered armchair
manufactured in accordance with the invention. The front and the
rear bar of the seat are indicated by oblique shading. The surface
of the seat is formed by a layer 100 of semi-rigid foam. A seat
bolster or cushion 152 is located on the seat. A back bolster of
cushion 154 is also provided. It may be seen that the seat is
provided only with the layer 100 of semi-rigid foam, while the back
panel 42 is provided with the layer 142 of soft foam in addition to
the layer 98 of semi-rigid foam. A reinforcing member 162 is
incorporated in each side of the seat and this is shown in FIG. 21.
The reinforcing member holds the screws 164 which secure the side
panel 46 and which are screwed into threaded plates 128 (FIG. 21).
The shorter limb of the reinforcing member also holds the screws
166 which secure the back panel 42. Finally, the reinforcing member
162 holds screws 168 which in turn secure the feet 170. In
accordance with the invention, the reinforcing member 162 in the
seat 44 and the reinforcing member 114 in the back panel 42 are
directed towards one another, so that the corresponding bores are
located opposite one another and the screws or the threaded bolts
can be passed therethrough. If screws, such as the screws 168, are
screwed into the reinforcing members, it is advantageous to weld
appropriate nuts onto the reinforcing members.
FIG. 20 shows the soft foam which has run through the holes 108, or
from the rear, into the hollow center cavity in the back 42 where
it forms a core 158 of soft foam. FIG. 20 also shows that the layer
142 of soft foam is thickened above the top of the back panel 42
where it forms a thickened portion 160. The thickened portion 160
is the result of the recess 74 illustrated in FIG. 1. Thus, a
person sitting in the armchair can rest his head on a soft,
resilient support. The same applies to the scroll 48, or to the
front bar of the seat 44, where it may be seen that the layers 100
and 102 of semi-rigid foam are thickened. This results from the
recesses 80 and 96 which may be seen in FIG. 1 and which are filled
by the semi-rigid foam.
FIG. 20 also shows the covering material 172, 174, 176 which covers
the back panel 42, the screen 48, and the seat 44 respectively. It
may also be seen that the ends of this covering material are
located in nailing grooves. In order to avoid rendering the drawing
obscure, the nailing grooves are not provided with reference
numerals in FIG. 20. The nailing grooves are located in the contact
surfaces between the back and the seat and between the seat and the
screen, so that they are concealed from the outside. In accordance
with the invention, the nailing grooves are constructed so that the
covering material has to pass over a plurality of sharp edges
before it terminates in a nailing groove. Contact against a
plurality of sharp edges occasions frictional forces which prevent
the covering material from being pulled out of the nailing
grooves.
Finally, it may be seen from FIG. 20 that the layers 98 and 100 of
semi-rigid foam have penetrated into the various foam grooves in
the back panel 42 and the seat 44 where they are anchored. This
prevents the layers of semi-rigid foam from becoming detached from
the hard foam elements when under stress.
FIGS. 22 and 23 show details of an alternative form of back in
which the reinforcing profiles are formed by single flat bars. A
single flat bar 200 is incorporated in each side of the back 42 and
serves to reinforce the back and to connect it to the side panels.
In the form illustrated, two hooks 202 are mounted on each flat
bar. The hooks 202 are mounted in plates or bushes 204 which are
welded onto the flat bars 200. The hooks 202 are screwed into the
bushes or plates 204. A hook 202 is illustrated in FIG. 31, drawn
to a somewhat larger scale, where the sloping face 203 on the
inside of the hook may be seen. A further flat bar 206 extends in
the bottom of the back 42. Bores 208 are provided in the flat bar
206. The bores 208 serve for receiving screws 122 which are
illustrated in FIG. 26. The heads of these screws are illustrated
by broken lines in FIG. 23. Bores 72 pass through the back in
alignment with the bores 208.
FIGS. 24 and 25 illustrate the seat 44. A flat bar 212 serving as a
reinforcement extends in the rear of the seat 44. Bores 214 pass
through the flat bar 212 and the hard foam of the seat. The bores
214 are in alignment with the bores 208 in the back and serve for
receiving the screw 122 illustrated in FIG. 26. The head of the
screw 122 abuts against the flat bar 206. A nut 213 is screwed onto
the other end of the screw 122 and abuts against the flat bar 212.
Threaded bushes 210 are formed in the underside of the seat 44. The
feet 170 (see for example FIG. 20) are screwed into the threaded
bushes 210. To improve the anchorage of the threaded bushes 210 in
the rigid foam of the seat, the threaded bushes 210 may be provided
with side projections 218 as illustrated in FIG. 28. In the same
manner as the other metal fittings, the threaded bushes 210 are
placed in the mould in which the rigid foam part is foamed and
shape. To prevent the thread of the threaded bush 210 from being
filled with foam, the threaded bush may be provided with a bottom
220 (FIG. 28).
FIG. 27 illustrates the manner in which a side panel 46 and the
scroll 48 are secured to the seat 44. Bushes 216 having a smooth
internal bore are located in the seat 44. Threaded bushes 222 are
located in the side panel 46 and in the screen 48 opposite the
bushes 216. Screws 164 are screwed into the threaded bushes 222
from the inside. The heads of the screws 164 then abut against the
flanges of the bushes 216.
FIGS. 28 to 30 show the threaded bush 222 into which the feet may
be screwed, and the smooth inserting bush 216.
A hook 202 secured to the flat bar 200 is illustrated in FIG. 31,
although it is drawn to a larger scale than the hook illustrated in
FIG. 23. The hook 202 is directed downwardly. An inserting bush 232
in the side panel 46 is located opposite the hook, as shown in FIG.
32. Details are illustrated in FIGS. 33 and 34. The inserting bush
232 has a cylindrical cavity 234. The top end of the bush has a
slotted hole 236. Two flanges 238 serve to improve the anchorage of
the bush in the foam material. The side panel 46 is slipped on from
below. The hook 202 then engages into the slot 236. The sloping
surface 203 (FIG. 31) runs on the bottom edge of the slot 236 and
draws the side panel 46 securely against the back 42. The upward
movement terminates when the side panel abuts against the lateral
projection 240 on the back panel.
FIG. 35 shows the manner in which a head rest 110 is secured to the
back panel 42. Hooks 202, having plates 204 of the kind already
described, are incorporated in the top edge of the back panel 42.
Inserting bushes 232 are incorporated in the head rest 110. The
head rest 110 is slipped onto the hooks 202 by means of these
bushes, in the same manner as described with reference to the side
panels. In this embodiment of upholstered seating furniture having
a head rest 110, side panels are used which extend upwardly beyond
the seat 44 and which conceal the ends of the head rest 110. The
side panels 46 are fitted after the head rest 110 has been fitted,
thus laterally securing the head rest 110.
In the embodiment illustrated in FIG. 36, the frame-shaped back 42
is in the shape of a U. The top half of the back is formed by a
resilient element 258 constructed in accordance with the invention.
Details of the resilient element are shown in FIGS. 37 and 38. The
resilient element comprises separate tubular pieces 260 which are
located one behind the other or adjacent to each other. The tubular
pieces may be made from any suitable material. In accordance with
the invention, it is advisable to manufacture the tubular pieces
from rigid foam. The tubular pieces 260 are provided with pairs or
bores 262 located opposite one another. The pairs of bores are
staggered by 90.degree. relative to one another. Soft foam 264
enters the interior of the tubular pieces 260 through the bores
262. The gaps 266 between the tubular pieces are also filled with
soft foam, thus providing a resilient element. The resilient
element may be deflected in any direction, as illustrated in FIG.
38. The deflection terminates when the ends of the tubular pieces
260 abut against each other at one side. The hardness of the foam
is selected in conformity with the desired resilience. In the case
of the back panel 42 illustrated in FIG. 36, the entire back may be
filled with soft foam, or various layers of semi-rigid and soft
foam may be used as shown in FIG. 20.
The resilient element 258, which may also be used independently of
the chair constructed in accordance with the invention, is
illustrated in detail in FIGS. 39 to 44. Bends 268 are illustrated
in FIG. 39. FIG. 39 also shows that the gaps between the tubular
pieces do not have parallel walls, but are in the form of
wedge-shaped gaps. Such a wedge-shaped gap 270 is shown
particularly clearly in FIG. 40. Thus, the embodiment of the
resilient element illustrated in FIG. 39 can be deflected only in
the direction of the arrows. Thus, rigidity is increased when the
resilient element 258 is used in a back panel 42. The resilient
element can be deflected in only one direction, i.e. inwardly.
The resilient element illustrated in FIG. 40 is shown in its
deflected state in FIG. 41. The deflection is terminated when the
ends of the two tubular pieces 260 abut against one another and the
wedge-shaped gap 270 has changed into a gap having parallel
walls.
FIGS. 43 and 44 are similar to FIGS. 40 and 41. They illustrate the
principle of the present invention by which the maximum deflection
or resilience may be determined by varying the opening angle of the
wedge-shaped gaps 270.
While various arrangements of seating furniture have been described
in the drawings, and while various arrangements of resilient
element have been described in FIGS. 36 to 44, other arrangements
of seating furniture and resilient elements may be resorted to
without departing from the spirit and scope of the invention as
defined in the appended claims.
* * * * *