Note: Descriptions are shown in the official language in which they were submitted.
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LONGITUDINALLY LACED POSTURI'e~ED AND/OR
CONTOURED SPRING BEDDING PRODUCT
Background of the Invention
A known form of spring interior comprises a
plurality of longitudinally extending bands of springs
disposed side by side and connected together by
helical wires which extend transversely of the bands
and embrace portions of the bands. Several kinds of
bands of springs have been proposed for incorporation
in spring interiors. One kind of band, which is the
subject of British patent No. 2,143,731, will
hereinafter be referred to as a band of interlocked or
interlaced springs. It comprises a single length of
spring wire shaped to form a plurality of individual
coil springs arranged in a row, one. end turn of each
coil spring lying adjacent to a top face of the band
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and the other end turn of each coil spring lying
adjacent to a bottom face of the band, each coil
spring being of a rotational. hand opposite to the
rotational hand of the adjacent coils immediately
5 before and after it in the row, and being joined to
the adjacent coil springs by a pair of interconnecting
segments of wire integral with the coil springs. one
of the pair of interconn~ctinc~ segments is located in
the bottom face of the band, and the other of the pair
10 of interconnecting segments is located in the top face
of the band. Each interconnecaing segment comprises a
bridging portion between adjacent coils, which
bridging portion extends lengthwise of the row.
When bands of interlocked springs of the
15 type described hereinabove are assembled to form a
spring interior, they are disposed side by side and
interconnected by helical wires, some of which lie in
the top face of the spring interior and others of
which lie in the bottom face thereof, the top and
20 bottom faces of the spring interior being the faces
defined by the top and bottom faces of the bands
incorporated in the' spring interior. Each helical
wire extends across the bands of springs. and embraces
portions of wires of the bands that extend
25 transversely of the bands from the ends of the
bridging portions of the links. In the top face of
the spring interior the helical wires are disposed at
uniform intervals along the bands .of springs, the
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arrangement being such that there are two springs
disposed in the interval between each helical wire and
the next. There is a similar arrangement in the
bottom face of the spring interior.
In this description of the invention there
are references to faces of bands of springs and of
spring interiors. As the bands of springs and spring
interiors are, of course, of open-work or skeletal
form, the term °'face" must be. understood as referring
to to an imaginary surface defined by the relevant parts
of the bands or spring interiors. Furthermore, as the
wires and helical wires a:re of finite width or
thickness and as they sometimes overlap each other,
the term "face" cannot be understood as having a
15 strictly geometrical meaning. Nevertheless, as the
faces concerned are relatively extensive and are of
flat shape, their locations can in practice be
determined without difficulty or ambiguity.
It is customary for a bedding spring
20 interior or a seat spring interior to be incorporated
in an upholstered article. In such an article at
least one of the main faces. of the spring interior
(that is the top and bottom :faces thereof) is covered
by a layer or layers of padding. This is turn is
25 covered by a cover made of sheet material, such as
ticking or upholstery fabric.
Pressure is applied unevenly to the top
surface of a mattress or chair seat when a person
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reclines atop a mattress ox- sits atop a seating
surface. This uneven pressure or uneven loading of
the surface is a consequencE: of the uneven weight
distribution of a person on the surface. In the case
of a mattress, the heaviest portion of the body is
located approximately midway along the length of the
body, and consequently, a person reclining atop a
mattress tends to cause the mattress to deflect or sag
to a greater extent in the lengthwise center of the
mattress than at the ends. This uneven deflection in
turn results in a person rec:Lining atop the mattress
having an unnatural and uncomfortable misalignment
imparted to his or her spine.
To counter this uneven deflection of a
mattress when a person is reclining atop the mattress,
it has been proposed to reinforce or rigidify the
lengthwise center section of the mattress. Such
center section reinforcement: or rigidification has
taken the form of increasing the number or density of
springs in the center section of the mattress, using
different or firmer springs in the center section of
the mattress, or adding additional structure to the
center section to reinforce that section to a greater
extent than the end sections. One patent which
discloses differing zones of firmness in a spring
mattress is U.S. Patent No. 4,679,266. In this
patent, the zones of differing firmness are created by
the installation of coil springs of.differing firmness
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in each of the differing fix:~mness zones. But, the
mattress disclosed in this U.S. patent, as well as all
spring mattresses which are characterized by zones of
differing firmness, has in t:he past been relatively
expensive to manufacture, primarily because of the
difficulty of automating the manufacture and,
particularly, the assembly of such mattresses or
spring assemblies.
It has therefore been an objective of this
invention to provide an improved method and apparatus
for imparting differing firmness to differing
lengthwise sections of a spring mattress or spring
seating assembly.
Still another objective of this invention
has been to provide an improved method and apparatus
for increasing the firmness of selected lengthwise
sections of a bedding or seating spring interior of
the interlocked spring type described hereinabove.
Summary of the Invention
The invention of this application which
achieves these objectives comprises a spring interior
having a plurality of transversely extending bands of
interlocked or interlaced c~oi1 springs wherein the
bands are disposed side by side so that their top
faces lie in a top main face of the spring interior
and their bottom faces lie in a bottom main face of
the spring interior. The bands of springs are
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interconnected by longitudinally extending helical
wires 'lying in the top and bottom faces of the bands
and extending across the band:. with each helical wire
embracing portions of wires of the bands that extend
5 transversely of the bands. In order to increase the
firmness or the contour of a selected section of the
spring interior, as for example, the lengthwise,
center one-third of the spring interior, the
transversely extending bands o~f interlocked springs in
10 this selected section are foamed by wire of heavier
gauge (greater diameter) or greater height (when in
the relaxed state) than the bands of the non-selected
sections.
The primary advantage of the invention of
15 this application is that it enables selected sections
or portions of spring interiors made from multiple
bands of interlocked or interlaced coils to be
inexpensively and easily increased in firmness or
contour by currently existing automated equipment
20 without substantial changes being required to that
equipment. Specifically, existing equipment need only
be reoriented and slightly modified by well-known and
easily accomplished modifications in order to enable
that equipment to produce the novel spring interior of
25 this invention.
Spring interiors made from multiple bands of
interlocked or interlaced coil springs of the type
described hereinabove are currently made by first
':
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forming the bands in the manner described in British
Patent No. 937,644 and then coiling those
interconnected bands into long, continuous lengths of
interlaced coil springs interconnected by
5 interconnecting segments. Those continuous lengths of
coil springs each typically contain many times more
individual bands than are required to form a single
bedding spring interior. After the bands are formed
into coils, they are conventionally moved to an
10 assembly machine, such as the machine described in
British Patent No. 1,095,980. This machine is
operable to simultaneously feed bands longitudinally
from several coils into the aasembly machine where the
individual bands are interconnected by transversely
15 extending helical lacing wirea.
Because the individual bands of springs in
the spring interior are each uncoiled from a separate
coil of bands of springs, each band of coil springs of
a spring interior may be made: of a differing gauge or
20 diameter wire from the other bands of the said spring
interior. Alternatively, each band of coil springs
may be comprised of coils which, in the relaxed state,
differ in height from the coals of the adjacent bands
of coil springs. This characteristic is not of any
25 particular advantage when applied to conventional
prior art spring interiors made from multiple bands of
longitudinally extending interlaced coils, but when
applied to spring interiors of this.,invention wherein
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the bands extend transversely of the spring interior
and are longitudinally laced, it is very advantageous.
Specifically, when applied t~o spring interiors made
from transversely extending bands of interlaced coil
5 springs, it enables longitudinal sections of the
spring interior to be "posturized°' or made of
differing height than other sections of the same
spring interior upon currently available spring
forming and assembly machines without substantial
10 modification of those machinea. In other words, this
invention enables spring interiors made from bands of
interlaced coils to be very inexpensively "posturized"
or contoured, i.e., made of differing firmness and/or
heights throughout the length of the spring interior.
15 These and other objects and advantages of
this invention will become more readily apparent from
the following description of the drawings in which:
Figure 1 is a top plan view, partially
broken away, of a mattress incorporating the invention
20 of this application.
Figure 2 is a cross-sectional view taken on
Line 2-2 of Figure 1.
Figure 3 is a perspective view of a portion
of one band or row of spring: embodied in the mattress
25 of Figure 1.
Figure 4 is a diagrammatic view of the
method of assembly of a spring interior made in
accordance with the invention of this application.
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With reference first to Figures 1-3, there
is illustrated a mattress 20 embodying the invention
of this application. This mattress comprises a spring
interior 21 on the top and bottom surfaces of which
there is a pad 19. An upholstered covering 18 encases
the spring interior 21 and the: pads 19.
The spring interior 21 is formed from a
plurality of bands of springs 22 which extend
transversely of the mattress. These bands of springs
22 are laced together by heli<:al lacing wires 23 which
extend longitudinally of the spring interior and
secure the bands of springs i.n an assembled relation.
A border wire 24 extends completely around the
periphery of the spring interior in the top and bottom
planes 25, 26, respectively, of the interior and is
secured to the outermost edge of the spring interior
in these planes by conventional sheet metal clips 27.
Each band of springs 22, a portion of one of
which is illustrated in Figui:es 2 and 3, is made from
a single length of spring wire shaped to form a
plurality of individual coil springs 31 arranged in a
row. Each coil spring 31 comprises about two and
one-half turns of wire. The axis of each coil spring
is not upright but is inclined slightly lengthwise of
the band, each spring being inclined in a direction
opposite to that in which it;s two adjacent springs in
the row are inclined. The end turns of the coil
springs 31 lie adjacent to the top, and bottom faces
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25 , 26 of the band. Each coil spring, such as that
numbered 31b (Figure 3), is so coiled as to have a
hand opposite to the hand of the adjacent coil
springs, such as 31a and 31c, immediately before and
5 after it in the row. Each coil spring is joined to
the next adjacent coil springy by two interconnecting
segments 35, 36 (Figure 2) of the wire integral with
the coil springs. One of 'the two interconnecting
segments 35, 36 is in the top face 25 of the band 22,
10 and the other is in the bottom face 26 thereof . For
example, coil spring 31a (Figure 3) is connected to
coil spring 31b by interconnecting segment 35, which
is in the bottom face of the band, and the coil spring
31b is connected to coil spring 31c by interconnecting
15 segment 36, which is in the top face of the band.
Each interconnecting segment 35, 36 comprises a
bridging portion 37, which extends transversely of the
row of coil springs and end portions 38 which extend
in a direction normal to the: transverse axis of the
20 band 22. Those end portions 38 of the interconnecting
segments 35, 36 also lie in the top and bottom faces
25, 26 of the band 22.
Each bridging portion 37, in addition to
extending transversely of the: band, also has a center
25 portion which extends longitudinally thereof to form a
supporting structure 40. In the embodiment of Figures
1-4, the supporting structure 40 is in the form of a
V-shaped indentation 41 of wire lyingt in the top 25 or
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bottom face 26 of the band 22, as the case may be, and
extending to one side of the reamainder of the bridging
portion 37 of which it forms a part. Each V-shaped
indentation 41 lies halfway between the end portions
38 of the interconnecting segment of which it forms a
part, and it extends from one: side face of the band
toward the other side face thereof.
The adjacent coils of each band of coils 22
are interlaced or interwoven to the extent of having
one intermediate turn of each coil interwoven with one
intermediate turn or revolution of each adjacent coil.
That is, and with reference to Figures 2 and 3, the
coil 31b has one turn or revolution interlaced or
interwoven with the adjacent coil 31a and another turn
or revolution interwoven or :interlaced with one turn
of the adjacent coil 31c. Thus, each coil 31, except
for the endmost coils of a band of springs 22, has two
turns or revolutions interlaced with turns or
revolutions of the two adjacent coils, and the endmost
coil 31 has one turn or revolution interlaced with one
turn or revolution of the actjacent coil of the same
band 22 of coil springs.
The method of manufacturing and the
apparatus for manufacturing the band of springs
illustrated in Figures 2 and 3 is described and
illustrated in British Patent: No. 937,644. After the
rows of coil springs are formed, each coil spring is
interlaced with the next by having. an intermediate
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turn thereof passed around an intermediate turn of the
next spring. After interlacing of adjacent coils, the
formed and interlaced coil ~~prings are rolled into
large rolls 39 of interconnected coil springs.
In order to form a apring interior from the
rolls of interconnected coil springs, a plurality of
lengths or bands of coil springs 22 are unwound from
rolls 39 of coil springs and are positioned in
side-by-side relationship with each band extending
10 transversely or across the short dimension of ,the
spring interior. Longitudin<~lly extending preformed
helical wires 23 are then attached to the adjacent
bands of coil springs. The helical lacing wires 23
lie in the top and bottom faces 25, 26 of the bands
15 and extend at right angles t~o the transverse axes of
the bands. Each longitudinally extending helical
lacing wire 23 embraces one pair of closely adjacent
end portions 38 of each transversely extending band.
In accordance with the practice of one
20 aspect of the invention oiE this application, one
section 20a of the mattress :?0 and spring interior 21
is posturized or increased in. firmness relative to the
endmost sections 20b and 20c. "Posturization" is a
term of art used to describe the increasing of the
25 firmness of one section of a mattress or spring
product relative to another section. In one preferred
embodiment of this invention, the posturization is the
practice of increasing the firmness of the lengthwise,
G ~ w~ i'n $.5
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centermost one-third section o:E the mattress. This is
the section which supports the: greatest concentration
of weight of a person reclining atop a mattress and is
therefore the section most subject to sagging or
drooping relative to the other endmost sections. To
prevent that sagging or drooping which can cause
discomfort of a person reclining atop the mattress
because of the sag or unnatural curvature of the spine
which occurs in the most heavily loaded, centermost
section of the mattress, this section is the one which
is commonly increased in firmness.
To increase the firmness of this centermost
section 20a of the mattress and spring interior 21,
the spring interior 21, the centermost five bands of
coil springs 22a which extend transversely of the
spring interior contain coil springs 31 which are of
increased firmness relative to the coil springs of all
of the other bands of coil springs. In the preferred
embodiment of this invention, this increased firmness
is imparted by having the cenitermost bands 22a of coil
springs made from heavier gauge wire than that from
which the other endmost sections 20b, 20c are made.
For example, and in one preferred embodiment, the
centermost section 20a was m<ide from bands of 14 1/2
gauge wire approximately .07E~ inches in diameter, and
the endmost sections 20b and 20c were made from 15
gauge wire approximately .072 inches in diameter.
Because the individual bands of springs are uncoiled
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from rolls of interlaced coil springs, as opposed to
being fed directly into the ;assembly machine from a
coil forming machine, the bands of coil springs of the
spring interior may easily be varied in gauge or wire
diameter. Thereby, the i:irmness of differing
longitudinal portions of the spring interior may be
easily and inexpensively varied without substantially
increasing the cost of the spring interior.
While in the preferred embodiment, the
spring interior 21 has been described as containing
five transverse rows of increased firmness coil
springs in the longitudinal center portion of the
spring interior, it could, of course, contain greater
or lesser numbers of rows of differing firmness coils,
depending upon the length of the section to be
increased in firmness. Alternatively, the bands of
increased firmness coils could be located at the ends
of the spring interior, as il:Lustrated in Figure 1, so
as to impart increased edge firmness at the ends of
the spring interior. Alternatively, rather than
having the wires from which the center or end portions
of the spring interior differ in gauge or diameter,
the wires could all be of the same diameter, but
differ in tensile strength or in relaxed height of the
individual coils of the bands of coil springs so as to
impart differing coil firmness to the bands of coil
springs when compressed and assembled in the different
longitudinal sections of tree spring interior. If
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bands of springs of differing Height of the individual
coils in the relaxed state are used to increase the
firmness of the bands, rather than differing gauge
wire, then the spring interior' may be contoured, when
upholstered, so as to impart higher or lower ends than
centers or vice versa, etc.
While I have described only a relatively few
preferred embodiments of my invention, persons skilled
in the art to which it applies will appreciate changes
and modifications which may be: made without departing
from the spirit of my invention. Therefore, I do not
intend to be limited except by the scope of the
following appended claims:
I claim:
