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US-12622530-B2 - Welding apparatus for strings of springs

US12622530B2US 12622530 B2US12622530 B2US 12622530B2US-12622530-B2

Abstract

A pocketed spring assembly comprises parallel strings, each string joined to at least one adjacent string. At least some of the strings have springs of different gauge wire and some of the pockets of the strings having springs of different gauge wire are spliced together. At least some of the strings have springs of different geometries and some of the pockets of the strings having springs of different geometries are spliced together. At least some strings may have end sections with springs different than a middle section therebetween, the springs of the end sections being firmer than the springs of the middle section.

Inventors

  • Guido Eigenmann
  • Darrell A. Richmond
  • Bernhard Bauer
  • Urs Liechti
  • Andreas Meier

Assignees

  • L&P PROPERTY MANAGEMENT COMPANY

Dates

Publication Date
20260512
Application Date
20240304

Claims (20)

  1. 1 . In combination, a first supply string of springs, a second supply string of springs and a welding apparatus, the combination comprising: a first supply string of springs; a second supply string of springs; and a welding apparatus for joining two strings of pocketed coil springs, the welding apparatus comprising; a first set of clamps for holding and moving an upstream tab of a starting string of pocketed coil springs, the starting string of pocketed coil springs being downstream of the clamps, a second set of clamps for holding and moving a downstream tab of the first supply string of pocketed coil springs, the second set of clamps being offset from the first set of clamps, a third set of clamps for holding and moving a downstream tab of the second supply string of pocketed coil springs, the third set of clamps being in-line with the first set of clamps, a cutter movable between a raised position when it is not being used and a lowered position; a welding horn, and an anvil, the welding horn and anvil being moveable between the first and third sets of clamps.
  2. 2 . The combination of claim 1 wherein the second set of clamps may be interchanged with the third set of clamps.
  3. 3 . The combination of claim 1 further comprising first and second coilers.
  4. 4 . The combination of claim 1 wherein the welding horn and anvil are moved together between the first and third sets of clamps to weld overlapping tabs of fabric together in a weld.
  5. 5 . The combination of claim 1 wherein the welding horn and anvil are separated to allow a combined string of pocketed coil springs to move downstream.
  6. 6 . The combination of claim 5 wherein the first set of clamps are separated to allow the combined string of pocketed coil springs to move downstream.
  7. 7 . The combination of claim 1 further comprising an assembler downstream of the welding horn and anvil.
  8. 8 . In combination, a first supply string of springs, a second supply string of springs and a welding apparatus, the combination comprising: a first supply string of springs; a second supply string of springs; and a welding apparatus comprising a welding horn, an anvil, the welding horn and anvil being moveable between open and closed positions, a first set of clamps for holding and moving an upstream tab of a starting string of pocketed coil springs, the starting string of pocketed coil springs being downstream of the welding horn and anvil, a second set of clamps for holding and moving a downstream tab of a first supply string of pocketed coil springs, the second set of clamps being upstream from the welding horn and anvil, a third set of clamps for holding and moving a downstream tab of a second supply string of pocketed coil springs, the third set of clamps being upstream from the welding horn and anvil; and a cutter movable between a raised position when it is not being used and a lowered position.
  9. 9 . The combination of claim 8 wherein one of the second and third sets of clamps is in-line with the first set of clamps.
  10. 10 . The combination of claim 9 wherein the other of the second and third sets of clamps is offset from the first set of clamps.
  11. 11 . The combination of claim 8 wherein the cutter is upstream of the first set of clamps.
  12. 12 . The combination of claim 8 wherein the first set of clamps open and close with the welding horn and anvil.
  13. 13 . The combination of claim 8 further comprising first and second coilers.
  14. 14 . The combination of claim 8 wherein the springs within strings having tabs welded together come from different coilers.
  15. 15 . In combination, a first supply string of springs, a second supply string of springs and a welding apparatus, said combination comprising: a first supply string of springs; a second supply string of springs; and a welding apparatus comprising a welding horn, an anvil, the welding horn and anvil being moveable between open and closed positions, a first set of clamps for holding and moving an upstream tab of a starting string of pocketed coil springs originating from a first coiler, the starting string of pocketed coil springs being downstream of the welding horn and anvil, a second set of clamps for holding and moving a downstream tab of a first supply string of pocketed coil springs originating from the first coiler, the second set of clamps being upstream from the welding horn and anvil, a third set of clamps for holding and moving a downstream tab of a second supply string of pocketed coil springs originating from a second coiler, the third set of clamps being upstream from the welding horn and anvil; and a cutter movable between a first position when it is not being used and a second position.
  16. 16 . The combination of claim 15 wherein each of the second and third sets of clamps is movable between an offset position and an in-line position, in-line with the starting string of pocketed coil springs.
  17. 17 . The combination of claim 15 wherein the springs within strings having tabs welded together come from different coilers.
  18. 18 . The combination of claim 15 wherein the welding horn and anvil are moveable between the first set of clamps and one of the second and third sets of clamps.
  19. 19 . The combination of claim 15 wherein the welding horn and anvil create a combined string of springs comprising the starting string of pocketed coil springs and one of the other strings of pocketed coil springs.
  20. 20 . The combination of claim 19 wherein the welding horn and anvil are open allowing the combined string of pocketed coil springs to move to an assembler.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 17/212,287 filed Mar. 25, 2021, a Divisional of U.S. patent application Ser. No. 16/418,041 filed May 21, 2019 (pending), which claims the benefit of priority to U.S. Provisional Patent Application No. 62/684,334 filed Jun. 13, 2018, each one of which is fully incorporated herein. FIELD OF THE INVENTION This invention relates generally to bedding and seating products and, more particularly, to pocketed spring assemblies used in bedding and seating products. BACKGROUND OF THE INVENTION Mattress spring core construction over the years has been a continuously improving art with advancements in materials and machine technology. A well-known form of spring core construction is known as a Marshall spring construction wherein metal coil springs are encapsulated in individual pockets of fabric and formed as elongate or continuous strings of pocketed coil springs. In an earlier form, these strings of coil springs were manufactured by folding an elongate piece of fabric in half lengthwise to form two plies of fabric and stitching transverse and longitudinal seams to join the plies of fabric to define pockets within which the springs were enveloped. Improvements in spring core constructions have involved the use of fabrics, which are thermally or ultrasonically weldable to themselves. One such cost-effective fabric is a spun-bonded polypropylene fabric. By using such welding techniques, these fabrics have been advantageously used to create strings of individually pocketed coil springs wherein transverse and longitudinal welds, instead of stitching, are used to form the pockets encapsulating the springs. Once strings of pocketed springs are constructed, they may be assembled to form a spring core construction for a mattress, cushion or the like by a variety of methods. For example, multiple or continuous strings may be arranged in a row pattern corresponding to the desired size and shape of a mattress or the like, and adjacent rows of strings may be interconnected by a variety of methods. The result is a unitary assembly of pocketed coil springs serving as a complete spring core assembly. A pocketed spring assembly may be surrounded with a border made of foam or any other suitable material to provide edge support around the perimeter of the pocketed spring assembly. Such a pocketed spring assembly is mounted upon a base and is completely enclosed within an upholstered covering material. The base and border are known in the industry as a “bucket” into which a pocketed spring assembly may be inserted before the “bucket” is covered with one or more padding or cushioning layers. Upon receiving multiple pocketed spring assemblies, a mattress manufacturer must insert each of the pocketed spring assemblies inside a bucket specifically constructed to receive a specified size of pocketed spring assembly. The mattress manufacturer must construct the foam encasements or “buckets” of different sizes via separate processes, which have proven to be costly due to the labor cost required. Mattress manufacturers would prefer to eliminate the process of building foam encasements or “buckets” and instead receive a pocketed spring assembly within built-in edge supports along all four sides of the pocketed spring assembly. It is generally known within the bedding industry that edge supports made of pocketed springs are more durable than foam edge supports. Pocketed spring assemblies having pocketed spring edge supports may be roll packed for shipping whereas those having foam edge supports are not easily roll packed for shipping. Pocketed spring assemblies made by joining parallel strings of individually pocketed springs have been made with four sides of edge support due to pocket coil machines capable of changing the springs within a strand or string of individually pocketed springs. Such modern pocket coil machines may further create posturized pocketed spring assemblies with zones or areas of different firmness. While modern pocket coil machines may change springs “on the fly”, the springs being individually pocketed to create edge support, the springs come from the same coiler, so the springs are all the same gauge within a string. Therefore, there is a need for a pocketed spring assembly which has different zones or regions of different firmness due to different springs within the pockets being made from different coilers and some pockets within a string being spliced together. There is further a need for a pocketed spring assembly which has four sides of edge support with the end sections of the internal strings being made of a heavier gauge wire than the internal springs. There is further a need for a method of making a continuous string of springs having sections of different properties or geometries to be inserted into an assembler. SUMMARY OF THE INVENTION According to one aspect of the invention, a bedding or seating pr