AU2017218566B2

AU2017218566B2 - Resilient unit and method of manufacture

Info

Publication number: AU2017218566B2
Application number: AU2017218566A
Authority: AU
Inventors: David Clare; Michael Gallagher; Simon Spinks
Original assignee: HS Products Ltd
Current assignee: HS Products Ltd
Priority date: 2016-02-10
Filing date: 2017-02-09
Publication date: 2022-11-24
Anticipated expiration: 2037-02-09
Also published as: WO2017137754A1; GB2547336A; KR20180109993A; CN108697243A; JP2019504685A; EP3413758A1; MX2018009711A; US20190045940A1; ZA201805000B; AU2017218566A1; CA3014151A1; GB2547336B; GB201602378D0; BR112018016014A2; GB201702159D0; EA201891801A1; SG11201806331XA

Abstract

A resilient unit (180), such as for a mattress, comprises a folded pad containing rows of resilient elements (120) in discrete pockets formed between superposed sheets of material joined at locations between adjacent resilient elements. Between at least some adjacent resilient elements the sheets form a gusset (160) which acts as a hinge when the pad is folded to form the resilient unit.

Description

Resilient Unit and Method of Manufacture

The present invention relates to a resilient unit, and to a

method of making a resilient unit, and is concerned

particularly, but not exclusively, with a resilient unit

that can be used for example in an upholstered article such

as a mattress or similar.

Pocketed springs, otherwise known as encased springs, are

used in upholstered articles such as mattresses. Most

pocketed spring units comprise coil springs encased

individually in pockets of fabric material formed by

folding over a sheet of fabric to form two leaves that

envelope the springs, and then attaching the leaves

together between the springs so as to form a string of

springs. The strings are then joined to form an array of

springs as a pocketed spring unit. The joining of the

strings together to form an array is achieved either by

gluing the strings together along the cylindrical surfaces

of the pocketed springs, one string to the next, and so on

until the unit is formed, or else by arranging the strings

beside each other in the manner of an array, and then

gluing sheets of fabric to the cylindrical ends of the

pocketed springs, above and below, so as to form the unit.

In view of its relatively high cost, there is a desire to

reduce the quantity of adhesive used in the manufacture of

such units.

An alternative method of forming an array of pocketed

springs is described in our European Patent No. EP 19939473

in which springs are introduced between axially superposed sheets of material that are then joined at locations between the springs.

The present invention is defined in the attached

independent claims, to which reference should now be made.

Further, preferred features may be found in the sub-claims

appended thereto.

Any discussion of documents, acts, materials, devices,

articles or the like which has been included in the present

specification is not to be taken as an admission that any

or all of these matters form part of the prior art base or

were common general knowledge in the field relevant to the

present disclosure as it existed before the priority date

of each of the appended claims.

Throughout this specification the word "comprise", or

variations such as "comprises" or "comprising", will be

understood to imply the inclusion of a stated element,

integer or step, or group of elements, integers or steps,

but not the exclusion of any other element, integer or

step, or group of elements, integers or steps.

According to one aspect of the present invention, there is

provided a resilient unit comprising a folded pad

containing plural rows of springs arranged side by side in

a longitudinal direction extending transverse to the extent

of each row, wherein the springs are in discrete pockets

formed by superposed continuous sheets of material joined

between springs in adjacent rows, wherein for at least some

of the rows, the continuous sheets are joined at two or

more attachment points spaced longitudinally between springs in adjacent successive rows of the unit, wherein in an unfolded configuration, the attachment points lie axially in line with the springs, and when the pad is folded to form the resilient unit the attachment points form a gusset which acts as a hinge between the adjacent rows.

Preferably the pad comprises a plurality of gussets, each

between adjacent pairs of resilient elements in a

longitudinal direction of the pad.

Preferably successive gussets are located on alternate

sides of the folded pad.

Preferably at least some of the resilient elements have

axes that extend between gussets in the folded pad.

Preferably at least some of the resilient elements have

axes that are aligned in a substantially parallel fashion

in the folded pad.

In a preferred arrangement, the sheets are joined at two or

more spaced locations between adjacent resilient elements

to form the gusset.

A single resilient element may be located between

successive gussets. Alternatively, or in addition, a

plurality of resilient elements may be located between

successive gussets in the pad.

The resilient elements may comprise springs. Preferably the

resilient elements comprise coil springs, which may be of

metal wire.

The springs may be substantially cylindrical in shape. Preferably, the springs comprise plural coils and in at

least some springs the coil at one end, more preferably the

coils at each end, is of a reduced diameter. The springs

may be other than cylindrical, such as conical or barrel

shaped for example. This is so that, when the pad is in the

folded configuration the free end or ends of the endmost

coils of adjacent springs do not interfere with or catch

upon one another.

For at least some of the springs the axial length of the

spring may exceed the maximum diameter of the spring.

Alternatively or in addition, for at least some of the

springs the axial length of the spring may be substantially

equal to, or may be less than, the maximum diameter of the

spring.

In the folded pad at least some adjacent resilient elements

may be attached together. The adjacent elements may be

attached together along an axially extending surface, more

preferably a substantially cylindrical surface, of the

resilient elements in the folded pad. Adjacent elements may

be attached together for example by gluing or welding, such

as ultrasonic welding, of the sheet of material to itself.

Alternatively, or in addition, the folded pad may be held

in its folded configuration by a retention member, which

may comprise a frame or envelope. The retention member may

comprise a loop or band passing around the folded pad to

prevent it from unfolding.

Alternatively or in addition, the folded pad may be held in

its folded configuration by its attachment to a cover sheet

or sheets. The cover sheet or sheets may cover one or both

sides of the folded pad, and may be attached to the folded

pad by adhesive or more preferably by welding, preferably

to one or more positions which may comprise the gussets of

the pad.

Alternatively, or in addition, the folded pad may be

retained in a folded configuration by a case or bag. The

case or bag may include padding or cushioning material and

the folded pad inside the case may substantially comprise a

mattress.

In a preferred arrangement the folded unit comprises a fan

folded, accordion-folded, concertina-folded or pleated pad.

The pad may be folded upon itself first one way and then

the other such that alternate gussets are located at first

one side then the other side of the folded unit.

The sheets are preferably of a thermally weldable material,

such as spun-bonded polyester.

In the folded unit at least some rows of resilient elements

comprise a first plurality of springs and a second

plurality of springs superposed on, and/or axially

adjacent, the first plurality.

The first and second pluralities of springs may differ in

one or more characteristics including, but not limited to:

length, diameter, stiffness, shape, number of coils and

gauge of spring material.

The resilient unit may comprise plural rows of resilient

elements arranged in an array.

In the unfolded pad, adjacent rows of resilient elements

may be offset from one another. This is so that, when

folded, the springs are able to fit together more closely,

for example to nest, which helps to form a more stable pad.

The sheets of material on opposed sides of the unit may

differ from one another in respect of at least one

characteristic from a group including optical, thermal,

tactile, structural, chemical and physical.

The at least one characteristic may comprise the presence,

absence or degree of at least one property from a group

including, waterproof, probiotic, antibacterial,

antistatic, flavour, fragrance, flame-retardance,

elasticity, wear resistance and permeability.

The first and second sheets of material may differ from one

another in thickness and/or weight.

In a preferred arrangement the first and second sheets may

differ from one another in one or more defined zones on one

or both layers, such that the layers may have substantially

identical characteristics in parts and may have different

characteristics in other parts.

The sheets are preferably joined around the periphery of

the unit.

According to a second aspect of the invention there is

provided a resilient pad for forming a resilient unit, the

pad comprising plural rows of resilient elements in

discrete pockets formed between superposed sheets of

material joined at locations between adjacent resilient

elements, wherein between at least some adjacent resilient

elements the sheets form a gusset which acts as a hinge

between resilient elements either side of the gusset when

the pad is folded to form a resilient unit.

The resilient pad may be in accordance with any statement

herein.

The invention also includes a method of making a resilient

unit, the method comprising forming a resilient pad

comprising plural rows of springs arranged side by side in

a longitudinal direction extending transverse to the extent

of each row, encasing a plurality of the springs in

discrete pockets formed by continuous superposed sheets of

material joined between springs in adjacent rows, wherein

for at least some of the rows, joining the continuous

sheets at two or more attachment points spaced

longitudinally between springs in adjacent successive rows

of the unit, so that in an unfolded configuration the

attachment points lie axially in line with the springs to

form gussets between the said rows, and fan-folding the pad

upon itself using the gussets as hinges, such that

alternate gussets become located on opposed sides of the

folded unit and axes of at least some of the springs become

substantially parallel.

The invention also includes an article having at least one

resilient unit according to any statement herein.

The invention also includes a mattress comprising a

resilient unit according to any statement herein, or made

according to a method according to any statement herein.

In accordance with the invention there is provided a seat

comprising a resilient unit according to any statement

herein.

The seat may be a seat for use in relation to a vehicle,

such as a wheeled vehicle, an aircraft, spacecraft or a

ship or boat, or a saddle for an animal. The seat may

comprise a chair, stool, bench, sofa or settee.

In accordance with another aspect there is provided a table

comprising a resilient unit according to any statement

herein. The table may be an operating table or massage

table, for example.

In accordance with a further aspect of the present

invention there is provided an article of flooring

comprising a resilient unit according to any statement

herein. The article of flooring may comprise a carpet, or

carpet underlay, or a sport mat or exercise mat, or may be

a leisure or sports surface either for indoor use or for

outdoor use.

In accordance with a still further aspect of the invention

there is provided a protective member, comprising a

resilient unit according to any statement herein. The protective member may comprise an article of clothing or headgear, or may be a protective shield to be worn on the body of a user, or for attachment to an article.

According to a still further aspect of the invention there

is provided an article of packaging, comprising a resilient

unit according to any statement herein.

The invention may include any combination of the features

or limitations referred to herein, except such a

combination of features as are mutually exclusive, or

mutually inconsistent.

A preferred embodiment of the present invention will now be

described. By way of example only, with reference to the

accompanying diagrammatic drawings, in which:

Figure 1 is a side view of a first embodiment of resilient

unit at a first stage of manufacture;

Figure 2 is a side view of the unit of Figure 1 at a second

stage of manufacture,

Figure 3 is a side view of the unit at a third stage of

manufacture;

Figure 4 is a perspective view of the unit of Figure 3;

Figure 5 is a side view of an alternative embodiment of

resilient unit at a second stage;

Figure 6 is a side view of the unit of Figure 5 at a third

stage of manufacture; and

Figure 7 shows a further alternative embodiment of

resilient unit in accordance with the present invention.

Resilient units for various uses, in accordance with

embodiments of the present invention, comprise pocketed

coil springs, which are sometimes referred to as encased

springs. The units typically comprise an array of metallic

coil springs individually encased in pockets formed by

bonding or otherwise joining together layers of material.

Turning to Figure 1, this shows, generally at 100, a pad

for making into a resilient panel, in accordance with an

embodiment of the present invention. The pad 110 is shown

in side view, and only a single set of pocketed springs can

be seen extending in a longitudinal direction indicated by

arrow X, which is also the direction in which the newly

formed pad is fed from the pocketing station (not shown).

In fact the pocketed springs are formed in an array, made

up of plural rows of springs side by side.

The pad comprises a number of springs 120 of coiled

metallic wire (shown in broken lines) encased in individual

pockets, one spring to a pocket in the example shown,

formed between superposed sheets 140 or layers of material

joined at positions P between the springs, preferably by

welding. The sheets 140 are joined at least at two spaced

apart positions P between each pair of adjacent springs

120, so that a gusset 160, or pleat, is formed between each

pair of springs.

An example of an apparatus and a method for making the pad

shown in Figure 1 can be seen in our European Patent No. EP

1 993 947 B1, the entire contents of which are incorporated

herein by reference.

Figure 2 shows a next step in the forming of the resilient

unit. The springs 120 have been turned within their

pockets, so that their axes A extend longitudinally,

between the weld points P. Turning the springs within their

pockets is achieved readily, particularly with tall

springs, as they have a tendency to turn in any case and

need only be urged to do so, for example by vibrating the

pad, or else by utilising a lip or ridge to catch an upper

leading edge of the spring, or a lower trailing edge,

thereby causing it to flip.

The pad is then folded, or pleated, in the manner of a fan,

concertina or accordion, so that alternate adjacent

pocketed springs are made to extend first one way, and then

the other way, to form a resilient unit 180. During

folding, the gussets act as hinges between rows of springs.

When the pad has been folded in this way the axes of

substantially all of the springs become aligned in a

direction that is generally transverse to the longitudinal

extent L of the unit 180.

Before folding, adhesive is applied at positions G on the

cylindrical surfaces of the pocketed springs. When the pad

has been folded into the configuration depicted in Figure 3

the pocketed springs can be urged together, causing the adhesive to join adjacent springs, thereby retaining the pad in the folded configuration.

In one embodiment not shown, in the unfolded pad adjacent

rows of springs are offset from one another in a direction

across the pad, transverse to the axes of the springs, so

that when the pad is folded the springs nest, each between

two adjacent springs of a neighbouring row. This provides

for a more stable pad.

The resultant unit is as shown in Figure 4, which is a

perspective view in which the plural rows of springs can be

seen. The gussets 160 extend across the width of the unit,

alternately above and below adjacent springs.

The pad can initially be formed with other combinations of

springs, and an example of an alternative embodiment is

shown in Figures 5 and 6.

Figure 5 shows a pad in which two different types of spring

are encased in individual pockets. The diagram shows the

springs after they have been turned so that their axes

extend longitudinally, along the length of the pad, between

welding positions P. A set 120a of long springs is formed

with a second set 120b of shorter springs. The springs are

each located within their own pockets, created by joining

the sheets 140 together at positions P. Between adjacent

pairs of springs a gusset 160 is formed by spaced apart

welds at positions P, and successive pairs are oriented

alternately so that when the pad is folded in the manner of

a fan, and glued, all of the shorter springs 120b are located above the longer springs 120a in an integrated stack.

The effect, in the finished unit 200, is of a layer of

short springs above a layer of long springs. Other

combinations of springs can be employed in the pad.

The springs can be chosen for their characteristics such as

stiffness and size and, as well as controlling the stacking

of different springs, the springs can be grouped into zones

along the extent of the unit, and combined in such a way as

to provide specifically desired performance

characteristics. These characteristics can be determined by

the intended use of the resilient unit.

This versatility comes from the way in which the initial

pad is produced, in which the positions of the weld points

can be programmed using computer-controlled means to

produce whatever pattern is required.

Since the gusset 160 joins or connects pairs of adjacent

springs at one end, they need only be joined at a minimum

of one other place, which in the example (Figure 3) is the

adhesive point G on the cylindrical surface of the pocketed

spring. This leads to a significant saving, possibly up to

50%, on adhesive.

In an alternative embodiment, shown in Figure 7, the folded

pad may be held in its folded configuration by a retention

member in the form of a loop or band B passing around the

folded pad to prevent it from unfolding. The band B may be

of the same material as the sheets 140, but does not have to be. As an alternative (not shown) the retention member may comprise a frame or envelope.

In another alternative embodiment (not shown), the folded

pad may be held in its folded configuration by its

attachment to a cover sheet or sheets. The cover sheet or

sheets may cover one or both sides of the folded pad, and

may be attached to the folded pad by adhesive or more

preferably by welding, preferably to one or more positions

which may comprise the gussets of the pad.

In a further alternative embodiment, the folded pad may be

retained in a folded configuration by a case or bag. The

case or bag may include padding or cushioning material and

the folded pad together with the case may substantially

comprise a mattress. The pad would be compressed axially

with respect to the springs and possibly also transversely

to this, between the edges, before being fed into the

padded case to form a complete mattress.

Reducing or even eliminating the glue usage has a

beneficial effect on the cost of production, and also makes

recycling more feasible. The glueless resilient mattress

can give up its steel springs easily and all of the pockets

remain joined together.

An additional substrate layer may be placed on top of the

pocketed springs, or below them, to improve comfort and/or

performance of the pad. The additional layer preferably

comprises natural materials such as hemp, cotton or wool,

to assist in the recyclability of the pad.

At least some of the springs may have coils of different

diameters at opposed ends. Such springs have a number of

advantages over springs in which the coils at each end of

the spring are of substantially the same diameter. Firstly,

the springs can be compressed to a substantially flat

configuration, with the smaller diameter coils lying within

the larger diameter coils. If the springs can be compressed

entirely within themselves, such that no touching of

adjacent coils takes place, this also provides a much

quieter panel than is the case when the coils repeatedly

abut one another.

Furthermore, the stiffness of a wire spring can be

increased by reducing coil diameter, for a given gauge of

wire. Therefore a narrower gauge spring can be made which

uses less material to produce the same spring stiffness. A

spring consisting of coils which reduce in diameter has a

desirable characteristic, in that its stiffness increases

progressively as it is compressed.

In an embodiment not shown, coils at one, or more

preferably both, ends of the spring are of a reduced

diameter. This can help to avoid interference between

adjacent the free end coils of adjacent springs when the

pad is folded. The springs may be other than cylindrical,

and may be, for example, conical, or barrel-shaped.

Various types of material are used in the manufacture of

the above-described pocketed springs, and particularly

common is the use of non-woven, spun-bonded polyester, as

this can readily be welded to itself using electrical

welding apparatus.

Many other combinations of springs and spring types may be

utilised in the resilient pad. These include, but are not

limited to: spring-within-spring arrangements, superposed

springs in stacks of two, three, four or more high, multi

stage or multi-phase springs, such as hybrid springs of

different coil types, and springs of different heights

alternating along the top of the folded pad, in the manner

of castellations (sometimes referred to in the bed-making

industry as a "Hi-Lo" unit). All of these combinations can

also be combined with springs of different gauge, shape,

height and with different degrees of pre-tensioning within

the pockets.

The invention described above allows for an easy

incorporation of large numbers of springs in a resilient

unit. A higher spring count means that the desired

characteristics of the unit can be achieved using springs

of a lesser gauge and of a lesser diameter, which in turn

requires less filling material.

Whilst endeavouring in the foregoing specification to draw

attention to those features of the invention believed to be

of particular importance, it should be understood that the

applicant claims protection in respect of any patentable

feature or combination of features referred to herein,

and/or shown in the drawings, whether or not particular

emphasis has been placed thereon.

Claims

1. A resilient unit comprising a folded pad containing

plural rows of springs arranged side by side in a

longitudinal direction extending transverse to the

extent of each row, wherein the springs are in

discrete pockets formed by superposed continuous

sheets of material joined between springs in adjacent

rows, wherein for at least some of the rows, the

continuous sheets are joined at two or more attachment

points spaced longitudinally between springs in

adjacent successive rows of the unit, wherein in an

unfolded configuration, the attachment points lie

axially in line with the springs, and when the pad is

folded to form the resilient unit the attachment

points form a gusset which acts as a hinge between the

adjacent rows.

2. A unit according to Claim 1, wherein the pad comprises

a plurality of gussets, each between adjacent pairs of

springs in the longitudinal direction of the pad.

3. A unit according to Claim 1 or 2, wherein successive

gussets are located on alternate sides of the folded

pad.

4. A unit according to any one of the preceding claims,

wherein at least some of the springs have axes that

extend between gussets.

5. A unit according to any one of the preceding claims,

wherein at least some of the springs have axes that are aligned in a substantially parallel fashion in the folded pad.

6. A unit according to any one of the preceding claims,

wherein a single spring is located between successive

gussets.

7. A unit according to any one of the preceding claims,

wherein a plurality of springs are located between

successive gussets in the pad.

8. A unit according to one any of the preceding claims

wherein the springs comprise coil springs, which of

metal wire.

9. A unit according to any one of the preceding claims,

wherein for at least some of the springs the axial

length of the spring exceeds the maximum diameter of

the spring.

10. A unit according to any one of the preceding claims, wherein for at least some of the springs the axial

length of the spring is substantially equal to, or

less than, the maximum diameter of the spring.

11. A unit according to any one of the preceding claims,

wherein in the folded pad at least some adjacent

springs are attached together.

12. A unit according to Claim 11, wherein the adjacent

springs are attached together along an axially

extending surface of the springs in the folded pad.

13. A unit according to any one of the preceding claims,

wherein the folded pad is held in its folded

configuration by a retention member.

14. A unit according to Claim 13, wherein the retention

member comprises a frame or envelope.

15. A unit according to Claim 13 or 14, wherein the

retention member comprises a loop or band passing

around the folded pad to prevent it from unfolding.

16. A unit according to any one of the preceding claims,

wherein the folded pad is held in its folded

configuration by its attachment to a cover sheet or

sheets.

17. A unit according to Claim 16, wherein the cover sheet

or sheets cover one or both sides of the folded pad.

18. A unit according to Claim 16 or 17, wherein the or

each cover sheet is attached to the folded pad by

adhesive or by welding to one or more positions.

19. A unit according to any one of Claims 16 to 18,

wherein the or each cover sheet is attached to one or

more gussets of the pad.

20. A unit according to any one of the preceding claims,

wherein the folded pad is retained in a folded

configuration by a case or bag.

21. A unit according to Claim 20, wherein the case or bag

includes padding or cushioning material.

22. A unit according to any one of the preceding claims,

wherein the unit comprises a fan-folded, accordion

folded, concertina-folded or pleated pad.

23. A unit according to any one of the preceding claims,

wherein the pad is folded upon itself first one way

and then the other such that alternate gussets are

located at first one side then the other side of the

folded unit.

24. A unit according to any one of the preceding claims,

wherein in the folded pad at least some rows of

springs comprise a first plurality of springs and a

second plurality of springs superposed on, and/or

axially adjacent, the first plurality.

25. A unit according to Claim 24, wherein the first and

second pluralities of springs differ in one or more

characteristics including, but not limited to: length,

diameter, stiffness, shape, number of coils and gauge

of spring material.

26. A unit according to any one of the preceding claims,

wherein the sheets of material on opposed sides of the

unit differ from one another in respect of at least

one characteristic from a group including optical,

thermal, tactile, structural, chemical and physical.

27. A method of making a resilient unit, the method

comprising forming a resilient pad comprising plural

rows of springs arranged side by side in a

longitudinal direction extending transverse to the extent of each row, encasing a plurality of the springs in discrete pockets formed by continuous superposed sheets of material joined between springs in adjacent rows, wherein for at least some of the rows, joining the continuous sheets at two or more attachment points spaced longitudinally between springs in adjacent successive rows of the unit, so that in an unfolded configuration the attachment points lie axially in line with the springs to form gussets between the said rows, and fan-folding the pad upon itself using the gussets as hinges, such that alternate gussets become located on opposed sides of the folded unit and axes of at least some of the springs become substantially parallel.

28. A mattress comprising a resilient unit according to

any of claims 1 to 26 or made by a method according to

Claim 27.