Abstract
A spool (100) of a linear string (110, 210, 310, 410) of pocketed springs is disclosed. The linear string of pocketed springs comprises springs (212, 312, 412) each provided in a textile pocket (214, 314, 414). The springs (212, 312, 412) comprise helically coiled steel wire springs. The textile pockets (214, 314, 414) are assembled to each other in linear direction. The linear string (110, 210, 310, 410) has a width of one textile pocket (214, 314, 414). The string (110, 210, 310, 410) of pocketed springs is present in the spool (100) spirally wound and in a compressed state such that the pocketed springs (212, 312, 412) can expand upon unwinding the string (110, 210, 310, 410) of pocketed springs from the spool (100).
Claims
1. A spool of a linear string of pocketed springs, wherein the linear string of pocketed springs comprises springs each provided in a textile pocket, wherein the springs comprise helically coiled steel wire springs; wherein the textile pockets are assembled to each other in linear direction; wherein the linear string has a width of one textile pocket; wherein the string of pocketed springs is present in the spool spirally wound and in a compressed state such that the pocketed springs can expand upon unwinding the string of pocketed springs from the spool.
2. The spool according to claim 1, wherein the linear string of pocketed springs is present as a multitude of layers in radial direction of the spool.
3. The spool according to claim 2, wherein successive layers of the linear string of pocketed springs make direct contact.
4. The spool according to claim 2, wherein an interlayer material is provided between the layers.
5. The spool according to claim 1, wherein, in longitudinal direction of the spool axis, a multitude of pockets are provided next to each other.
6. The spool according to claim 1, wherein the linear string of pocketed springs is wound in alternating first and second layers over the width direction of the spool; wherein after winding the string of pocketed springs in a first layer in a first width direction of the spool, the string of pocketed springs is wound in a second layer in the direction opposite to the first width direction over the width of the spool.
7. The spool according to claim 1, wherein the pockets have a height direction perpendicular to the length direction of the string of pocketed springs; and wherein the springs are provided in the pockets such that the height direction of the helically coiled steel wire spring is perpendicular to the height direction of the pockets.
8. The spool according to claim 1, wherein the height direction of the pockets is provided in radial direction of the spool.
9. The spool according to claim 1, wherein the linear string of pocketed springs in the spool comprises pockets in a first arrangement and pockets in a second arrangement; wherein the pockets in the second arrangement differ from the pockets of the first arrangement in that the pockets have been turned around the length direction of the string over 180° or over a multiple of 180°; preferably pockets according to the first arrangement alternate in the spool along the length of the linear string of pocketed springs with pockets of the second arrangement.
10. The spool according to claim 1, wherein a fabric tape—preferably having the width of the string of pocketed springs—is glued on top of and/or at the bottom of the string of pocketed springs.
11. A method of manufacturing a two-dimensional pocketed spring core, e.g. for a mattress or for a cushion, comprising the steps of providing the spool of a linear string of pocketed springs according to claim 1; unwinding the linear string of pocketed springs from the spool and allowing the pocketed springs to relax to their uncompressed state; and assembling the linear string of pocketed springs into a two-dimensional pocketed spring core.
12. The method of manufacturing a two-dimensional pocketed spring core according to claim 11, comprising the steps of providing a plurality of spook of a linear string of pocketed springs according to claim 1; preferably wherein the pocketed springs of at least two of the plurality of spools of a linear string of pocketed springs differ in spring characteristics; unwinding the linear strings of pocketed springs from the spools and allowing the pocketed springs to relax to their uncompressed state; and assembling the linear strings of pocketed springs into a two-dimensional pocketed spring core; preferably thereby manufacturing a two-dimensional pocketed spring core having zones with different spring characteristics. 13, The method of manufacturing a two-dimensional pocketed spring core according to claim 11, comprising the steps of providing one or a plurality of spools of a linear string of pocketed springs according to claim 1 providing one or a plurality of machines for manufacturing strings of pocketed springs; unwinding linear string(s) from one or from more than one of the one or a plurality of spools allowing the pocketed springs to relax to their uncompressed state; and assembling into a two-dimensional spring core the unwound linear string(s) together with one or more strings of pocketed springs produced in-line with the assembly process on the one or a plurality of machines.
14. An apparatus for the assembly of a two-dimensional pocketed spring core, comprising one or a plurality of pay-off stands each for holding a spool of a linear string of pocketed springs as in claim 1; one or a plurality of machines for manufacturing strings of pocketed springs; an assembly station for assembling lengths of strings of pocketed springs to each other thereby obtaining a two-dimensional pocketed spring core; wherein the one or a plurality of machines are provided for manufacturing strings pocketed springs in line with the assembling on the assembling station; wherein the assembly station is provided for assembling in the two-dimensional spring core lengths of strings of pocketed springs unwound from the spool(s) on the one or a plurality of pay-off stands while allowing the pocketed springs to relax to their uncompressed state; and lengths of strings of pocketed springs produced inline by the one or plurality of machines.
15. The apparatus according to claim 14, wherein the apparatus comprises a control unit for controlling the feeding to the assembly station of the strings of pocketed springs from the spool and/or from the machines.
Description
BRIEF DESCRIPTION OF THE FIGURES IN THE DRAWINGS
[0036] FIG. 1 shows—according to the invention—a spool of a linear string of pocketed springs.
[0037] FIG. 2 shows an arrangement of a linear string of pocketed springs as can be used in the invention.
[0038] FIG. 3 shows another arrangement of a linear string of pocketed springs as can be used in the invention.
[0039] FIG. 3 shows another arrangement of a linear string of pocketed springs as can be used in the invention.
[0040] FIG. 5 shows an example of an apparatus according to the fifth aspect of the invention.
MODE(S) FOR CARRYING OUT THE INVENTION
[0041] FIG. 1 shows an exemplary spool 100 of a linear string of pocketed springs according to the first aspect of the invention. The exemplary spool comprises a core 102 and a linear string 110 of pocketed springs. The string 110 of pocketed springs is present in the spool spirally wound and in a compressed state such that the pocketed springs can expand upon unwinding the string of pocketed springs from the spool. The linear string 110 of pocketed springs is wound in multiple layers in radial direction of the spool. The linear string 110 of pocketed springs is wound in alternating first and second layers over the width direction of the spool. After winding the string of pocketed springs in a first layer in a first width direction of the spool, the string of pocketed springs is wound in a second layer in the direction opposite to the first width direction over the width of the spool. In the example, successive layers of the linear string of pocketed springs make direct contact. However, it is also possible (not shown in FIG. 1) to provide an interlayer material (e.g. paper, paperboard, a tape or a textile fabric) between the layers. The core can e.g. be a tube of paperboard. The linear string of pocketed springs can be fixed to the core at the start of winding the linear pocketed spring to the core. The last wound part of the linear string can be fixed in the spool such that the compressing tension on the pockets is maintained. The fixation can be done on a length of the linear spring previously wound, or on the paperboard core. The example of FIG. 1 shows the height direction of the pockets in radial direction of the spool.
[0042] A first example of arrangement of the linear string of pocketed springs in the spool is shown in FIG. 2. For the sake of clarity of illustration, FIG. 2 shows the linear string 210 of pocketed spring in uncompressed condition. On the spool, the linear string and the pockets are compressed. The linear string 210 of pocketed springs comprises springs 212 each provided in a textile pocket 214. The springs are helically coiled steel wire springs. The textile pockets are assembled to each other in linear direction. The linear string has a width of one textile pocket. The pockets are made from spunbonded nonwoven fabric by means of welds, more preferably by means of thermal welds. A line of welds 216 is provided in between the textile pockets. The pockets have a height direction indicated by H in FIG. 2. The height direction of the pockets is the direction that will provide the thickness of the 2D-core made with the string of pocketed springs. The string has a length direction indicated by L in FIG. 2. The height direction of the pockets is perpendicular to the length direction of the string of pocketed springs. The springs are provided in the pockets such that the height direction of the helically coiled steel wire spring is perpendicular to the height direction of the pockets. At or after unwinding the string from the spool, the springs need to be turned over 90° such that the height direction of the springs coincide with the height direction of the pockets. Turning the springs can be done without difficulty by simple mechanical means.
[0043] An alternative arrangement of the linear string of pocketed springs in the spool is shown in FIG. 3. For the sake of clarity of illustration, FIG. 3 shows the linear string 310 of pocketed spring in uncompressed condition. On the spool, the linear string and the pockets are compressed. The linear string 310 of pocketed springs comprises springs 312 each provided in a textile pocket 314. The springs are helically coiled steel wire springs. The textile pockets are assembled to each other in linear direction. The linear string has a width of one textile pocket. The pockets are made from spunbonded nonwoven fabric by means of welds, more preferably by means of thermal welds. A line of welds 316 is provided in between the textile pockets. The springs 312 are provided in the pockets 314 such that the height direction of the springs coincides with the height direction of the pockets. This is the orientation the springs have in two-dimensional pocketed spring cores.
[0044] Another—particularly beneficial—arrangement of the linear string of pocketed springs in the spool is shown in FIG. 4. For the sake of clarity of illustration, FIG. 4 shows the linear string 410 of pocketed spring in uncompressed condition. On the spool, the linear string and the pockets are compressed. The linear string 410 of pocketed springs comprises springs 412 each provided in a textile pocket 414, 415. The springs are helically coiled steel wire springs. The textile pockets are assembled to each other in linear direction. The linear string has a width of one textile pocket. The pockets are made from spunbonded nonwoven fabric by means of welds, more preferably by means of thermal welds. A line of welds 416 is provided in between the textile pockets. The linear string of pocketed springs in the spool comprises pockets 414 in a first arrangement and pockets 415 in a second arrangement. The pockets in the second arrangement differ from the pockets of the first arrangement in that the pockets have been turned around the length direction of the string over 180° . This turning will bring along a compression of the pockets (however, FIG. 4 shows the pockets in uncompressed condition, for the sake of illustration of the arrangement of springs and pockets in the linear string). In the example of FIG. 4 pockets 414 according to the first arrangement alternate in the spool with pockets 415 of the second arrangement along the length of the linear string of pocketed springs. The transition in the string of pocketed springs from a pocket 414 of the first arrangement to a pocket 415 of the second arrangement can be easily noticed via the rotation at the connection 416 of the pockets: this connection has been turned over 180°. In FIG. 4, the springs are oriented in such way that the height direction of the spring coincides with the height direction of the pockets as in FIG. 3. However, it is also possible to orient the springs in the way as shown in FIG. 2.
[0045] FIG. 5 shows in schematic representation an example of an apparatus 500 according to the fifth aspect of the invention. The apparatus 500 is provided for the assembly of a two-dimensional pocketed spring core 530 using linear strings of pocketed springs. The apparatus comprises a creel 540 comprising a plurality of pay-off stands, a machine 550 for manufacturing strings of pocketed springs; and an assembly station 560. Steel wire 552 and nonwoven fabric 554 are supplied to the machine 550 in order to manufacture strings of pocketed steel wire springs. The pay-off stands are each provided for holding a spool of a linear string of pocketed springs as in any embodiment of the first aspect of the invention. The assembly station is provided for assembling—in an otherwise known way—in the two-dimensional spring core lengths of strings of pocketed springs unwound from the spool(s) on the plurality of pay-off stands while allowing the pocketed springs to relax to their uncompressed state; and lengths of strings of pocketed springs produced inline by the one or plurality of machines. The apparatus can comprise a feeding device 562 for selecting and feeding the strings of pocketed springs—whether taken from the spools or produced in-line by the pocketed spring manufacturing machine to the assembly station. The apparatus can comprise a buffer 564, e.g. a bin, for temporarily buffering length of strings of pocketed springs produced by the pocketed spring manufacturing machine 550. This way, the machine can continuously manufacture pocketed springs. The apparatus can comprise a control unit for controlling the feeding of the strings of pocketed springs from the spools and/or from the pocketed spring manufacturing machine to the assembly station.
