WO2007031774A1

WO2007031774A1 - Pocketed spring units

Info

Publication number: WO2007031774A1
Application number: PCT/GB2006/003439
Authority: WO
Inventors: Simon Paul Spinks; David Clare
Original assignee: A Harrison (Bedding) Limited
Priority date: 2005-09-17
Filing date: 2006-09-15
Publication date: 2007-03-22
Also published as: US20110099812A1; ZA200802093B; US20120210676A1; CA2626919A1; EP1993947B1; CA2626919C; US20180072559A9; US20090266032A1; US20130247518A1; EP1993947A1; US10961112B2; GB0519009D0; DK1993947T3; US10167186B2; PL1993947T3; ES2470372T3; US7877964B2; US20190144261A1

Abstract

A method and apparatus for the production of a pocketed spring unit, the method comprising the steps of compressing and feeding a plurality of springs (42) into troughs (2A, 4A) or castellations in opposed conveyor belts (2, 4) , moving said springs (42) from said troughs (2A, 4A) or casetellations to a position between upper and lower layers of fabric or other material (ISA, 18A) , step-wise advancing said material (16A, 18A) and said springs (42) in the direction of the output of the apparatus and welding together said lengths of fabric or other material (16A, 18A) at each step-wise advancement by a plurality of sequentially controlled welding anvils (10) so as to form a plurality of discrete pockets (46) each containing a spring (42) . Apparatus for carrying out the method is disclosed.

Description

POCKETED SPRING UNITS

This invention relates to pocketed spring units, and to a method and

apparatus for forming such units.

There have been many prior proposals for forming pocketed spring

units, but it is felt that such prior proposals have been overly

complicated and costly to produce, and the present invention seeks to

obviate these and other disadvantages of such prior proposals.

According to one aspect of the present invention, there is provided a

method for the production of a pocketed spring unit comprising the

steps of compressing and feeding a plurality of springs into troughs or

castellations in opposed conveyor belts, moving said springs from said

troughs or castellations to a position between upper and lower layers

of fabric or other material, step-wise advancing said material and said

springs in the direction of the output of the apparatus and welding

together said lengths of fabric at each said step-wise advancement by

a plurality of sequentially controlled welding anvils so as to form a

plurality of discrete pockets each containing a spring. The method may include the additional step of forming the springs

immediately prior to the springs being compressed and fed into said

troughs or castellations.

According to another aspect of the present invention, there is

provided apparatus for forming a pocketed spring unit comprising

means for compressing and feeding springs between opposed

conveyor belts, means for moving said compressed springs from

between said conveyor belts in the direction of the output of the

apparatus to positions between upper and lower lengths of fabric

or other material, means for sequentially advancing said lengths and

said springs in said direction, and welding means for sequentially

welding together said lengths so as to form a plurality of discrete

pockets each containing a spring.

Preferably, said springs will be fed to the positions between the

opposed conveyor belts by means of an inserter mechanism, operation

of said mechanism simultaneously compressing said springs. The opposed conveyor belts will each consist of an endless castellated

or troughed belt, and the means to feed the compressed springs from

between the conveyor belts to positions between said lengths of

fabric or other material will preferably be power-driven spring

inserters having a plurality of arms adapted to enter and leave the

castellations or troughs in said belts, said arms being greater in overall

height than the height of the springs and making contact with said

springs to move said springs between said layers.

The welding means will preferably be a plurality of movable welding

anvils and a plurality of co-operating welding horns, said welding

means being adapted to sequentially weld said layers together at each

sequential movement of said layers and springs so as to form said

discrete pockets.

The apparatus may include a spring coiler as an integral part of the

apparatus, such coiler delivering the formed springs directly to the

spring compressor and feeder means. In order that the invention may be more readily understood, an

embodiment thereof will now be described, by way of example only,

reference being made to the accompanying drawings, wherein:

Figure 1 is a schematic side view of apparatus in accordance with the

invention;

Figures 2 A to 2D are schematic representations of a part of the

apparatus of Figure I₅ and showing its sequence of operations;

Figure 3 is an enlarged perspective view of another part of the

apparatus of Figure 1;

Figure 4 is an enlarged view of a part of Figure 3; and

Figure 5 is a schematic perspective view of a spring unit formed on

the apparatus of Figure 1.

Referring to the drawings and firstly to Figure I₅ the apparatus for

forming a spring unit comprises a spring compression and feeder, not

shown in Figure I₅ but referenced 20 in Figure 2A₅ spring delivery

belts 2 and 4, spring inserters 6 and associated cylinders 8, a plurality

of welding anvils, a plurality of air cylinders, and a plurality of welder horns, one each of these items being respectively referenced

1O₅ 12, and 14. Rolls 16 and 18 of fabric or other material are shown

associated with the apparatus.

Referring now to Figures 2A to 2D, the spring compressor 20

comprises a frusto-conical upper section 22, a straight-sided mid¬

section 24, and a forwardly-sloping bifurcated lower section 26.

Associated with the compressor 20 is a power-operated, preferably

compressed air-operated, pusher and ejector plate 28.

Figures 3 and 4 show the spring delivery belts 2 and 4, and the spring

inserter 6 in detail. Each delivery belt 2 and 4 is endless and is

castellated or troughed as indicated at 2A and 4A respectively. Each

of the delivery belts is indexable so as to be movable in the direction

of arrows 2B and 4B and is composed of any suitable material, but

preferably a plastics material, and one or both of the delivery belts

will be positively driven. The delivery belts 2 and 4 are journalled in

suitable frame members, not shown in the drawings. Associated with the spring delivery belts 2 and 4 is the spring

inserter 6 which is movable in the direction of arrows 30 and 32 by

the air cylinders 8. The spring inserter 6 consists of a plurality of

inserter arms 34 which are mounted on a suitable framework (not

shown) which in turn is connected to the air cylinders 8 so as to

enable said framework, and hence the inserter arms, to be moved in

the directions of the arrows 30 and 32. There will preferably be a

plurality of horizontally in-line spring inserters 6, each having a

plurality of inserter arms 34, and in a preferred embodiment of the

invention, there will be two inserters 6 each having three inserter arms

34, each inserter 6 being movable by an air cylinder 8. These spring

inserters 6 will preferably be linked so as to move in unison.

As clearly shown in Figure 4, the inserter arms 34 of the spring

inserters 6 will be of a depth and width such that they can pass into

and out of the castellations or troughs 2A and 4A of the spring

delivery belts 2 and 4 so as to enable the compressed springs to be fed

between the layers of fabric or other material being fed from the rolls 16 and 18 as will be hereinafter explained.

The welding anvils 10 and their associated air cylinders 12 are

operable, in conjunction with the welder horns 14, to work in a

predetermined and pre-programmed manner so as to form a required

pattern (as shown in Figure 5) and entrap individual springs between

the layers 16A and 18A of fabric or other material fed from the rolls

16 and 18. This will be explained in greater detail below.

Associated with the above-described apparatus is a spring coiler (not

shown) which is adapted to form individual springs for delivery to the

spring compressor 20. Such coiler may be an integral part of the

apparatus previously described, or alternatively the springs may be

pre-formed and delivered individually by suitable means to the spring

compressor.

hi operation, fabric or other material 16A and 18A is fed from the

rolls 16 and 18 and passes around guide rollers 36 and 38 and continues to move in the direction of arrow 40, Figure 1. As fabric or

other material 16A and 18A continues to be fed from the rolls 16 and

18, individual springs 42 are located in the spring compressor and

feeder 20 and contacted by the plate 28 which, moving in the

direction of arrow 28A, moves the spring 42 towards and against the

sloping section 26 so as to compress the spring axiaUy as shown in

Figure 2D. Continued movement of the plate 28 between the

bifurcations 26A and 26B moves the compressed spring into a slot 44

at the end of the spring compressor and feeder 20 and thence between

the belts 2 and 4 at the proximal extremities thereof.

The compressed spring 42 is moved by and between the belts 2 ands 4

in the direction of arrow 44 (Figure 3) towards the distal extremities

of the belts. When a predetermined number of springs 42 are located

in-line between the belts 2 and 4, the air cylinders 8 are actuated such

that the spring inserters 6 move towards the belts and such that the

inserter arms 34 move into the castellations or troughs 2A and 4A in

the belts, resulting in the springs 42 passing between the rollers 36 and 38 to the positions 42 A between the fabric or other material 16A and

18A.

When the row of springs 42 are at the position indicated by reference

numeral 42A, the air cylinders 12 and hence the welding anvils 10 are

actuated so as to entrap the springs in discrete pockets across the

width of the fabric or other material, one of such pockets being

indicated by reference numeral 46 in Figure 1.

hi the formation of the discrete pockets, during which the springs are

still in their compressed states, the multiple air cylinders control

individual welding anvils to produce a grid pattern of welds which

join the lengths of fabric or other material together, the welding anvils

working in cooperation with the plurality of welder horns 14.

Reference to Figure 5 will show the pattern of welds to form the

discrete pockets 46. Each of the longitudinal welding lines indicated

by reference numeral 48 is formed by a step movement of the lengths 16A and 18A of fabric or other material in the direction of the arrow

40 followed by a step welding process, selected welding anvils 10

being actuated every segment length 48A of the welding lines 48. In

the described embodiment of the invention, each segment length is

16mm, but it will be appreciated that such length may be changed.

Each of the lateral welding lines 50 is produced by the step movement

of the lengths 16A and 18Ato the required positions followed by the

actuation of all welding anvils, such actuation - in the embodiment of

the invention being described - being every 75mm, it again being

appreciated that such distance may be changed.

Electronic control devices, not shown in the drawings, control the step

movement of the lengths 16A and 18 A of fabric or other material.

In addition, electronic control devices (not shown) control the

compression and feeding of the springs between the conveyor belts 2

and 4, and the movement of the spring inserters 6 such that all the

sequences of the apparatus is precisely controlled. - li ¬

lt will be appreciated that the spring compressor and feeder may differ

from that shown in the drawings, and that the welding pattern may

differ to that described. The chosen welding pattern, as regards its

form and length of segments will be variable at will, and to some

extent may well be determined by the type and nature of the springs

being entrapped.

Thus the invention provides a method and apparatus for forming

a pocketed spring unit for incorporation into an upholstered unit, the

length and width of the pocketed spring unit being unlimited.

Finally, it will be appreciated that many variations may be made to the

apparatus of the invention without departing from the spirit thereof

and it is intended that any such variations are encompassed herein.

Claims

CLAIMS:

1. A method for the production of a pocketed spring unit

comprising the steps of compressing and feeding a plurality of springs

into troughs or castellations in opposed conveyor belts, moving said

springs from said troughs or casetellations to a position between upper

and lower layers of fabric or other material step-wise advancing said

material and said springs in the direction of the output of the apparatus

and welding together said lengths of fabric or other material at each

step-wise advancement by a plurality of sequentially controlled

welding anvils so as to form a plurality of discrete pockets each

containing a spring.

2. A method according to claim 1, including the step of forming

the springs immediately prior to the springs being compressed and fed

into said troughs or castellations.

3. Apparatus for forming a pocketed spring unit comprising means means for compressing and feeding springs between opposed

conveyor belts, means for moving said compressed springs from

between said conveyor belts in the direction of the output of the

apparatus to positions between upper and lower lengths of fabric or

other material, means for sequentially advancing said lengths and said

springs in said direction, and welding means for sequentially welding

together said lengths so as to form a plurality of discrete pockets each

containing a spring.

4. Apparatus according to Claim 3, wherein said springs are fed to

the positions between the opposed conveyor belts by means of an

inserter mechanism, operation of said mechanism simultaneously

compressing said springs.

5. Apparatus according to Claim 3 or Claim 4, wherein the

opposed conveyor belts each consist of an endless castellated or

troughed belt, each belt being indexable, and one at least of said belts

being positively driven.

6. Apparatus according to Claim 4, wherein the means to feed the

compressed springs between said lengths of fabric or other material are

power-driven spring inserters each having a plurality of arms adapted

to enter and leave the castellations or troughs in said belts, said arms

being greater in overall height than the height of the springs and

making contact with said springs to move said springs between said

layers of fabric or other material.

7. Apparatus according to any of Claims 3 to 6, wherein said

welding means is a plurality of movable welding anvils and a plurality

of co-operating welding horns, said welding means being adapted to

sequentially weld said layers together at each sequential movement of

said layers and said springs so as to form said discrete pockets.

8. Apparatus according to Claim 7, wherein the welding anvils are

movable by associated air cylinders and are operable, in conjunction

with the welding horns, to work in a predetermined and pre-

programmed manner so as to form a required pattern and entrap individual springs between the layers of fabric or other material.

9. Apparatus according to any of Claim 3 to 8, including a spring

coiler adapted to form individual springs for delivery to said spring

compressor.