Method of making extruded mesh body for vehicle seat and article made thereby

Abstract

To provide a body for a seat assembly and a method for a seat pad.SOLUTION: A body is composed of a plurality of extruded polymer filaments randomly oriented and bonded together to form a three-dimensional mesh structure. The body is elongated in an extrusion, or longitudinal, direction. First zones of the extruded polymer filaments having a first density and second zones of the extruded polymer filaments having a second density less than the first density. The first and second zones are separated by boundaries, or transition areas. There is provided a method of making a seat pad with extruded polymer filaments having different zones with different densities and hardness characteristics by controlling speed of a plurality of tractor belts in a cooling bath.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] (Reference to Related Applications) This application claims priority to U.S. Patent Application No. 18 / 962,730, filed on November 27, 2024, and also claims the benefit of U.S. Provisional Application No. 63 / 612,215, filed on December 19, 2023. Further, this application claims priority to Danish Patent Application No. PA202470196, filed on July 18, 2024. These disclosures are hereby incorporated by reference in their entirety into this specification.

[0002] Relates to an extrudate of polymeric filaments made according to a method of forming pads having different densities across the width of the extrudate.

Summary of the Invention

Means for Solving the Problems

[0003] According to one aspect of the present invention, there is provided an article comprising a body of a plurality of extruded polymeric filaments that are randomly oriented and joined to each other to form a three-dimensional mesh structure, the body being elongated in a longitudinal direction and comprising a first zone comprising the extruded polymeric filaments having a first density and a second zone comprising the extruded polymeric filaments having a second density lower than the first density.

[0004] According to another aspect of the present invention, there is provided a seat assembly comprising a seat frame, a seat cover, and a body comprising a plurality of extruded polymeric filaments that are randomly oriented and joined to each other to form an intermediate preform, the intermediate preform comprising a first zone of the extruded polymeric filaments having a first density and a second zone of the extruded polymeric filaments having a second density lower than the first density, the intermediate preform being shaped to form a molded seat cushion.

[0005] According to another aspect of the present invention, melting a polymer resin to form a molten polymer, extruding the molten polymer through a die head to form an extruded polymer filament, shaping and joining the extruded polymer filament into a strip of filaments having a predetermined cross-section, and pulling the strip of filaments into a cooling tank in a longitudinal direction using a plurality of tractor belts arranged transversely to the longitudinal direction, wherein each of the tractor belts moves one of a plurality of portions of the strip of filaments in the longitudinal direction, pulling the strip of filaments, and controlling the plurality of tractor belts to move one of the plurality of portions of the strip of filaments at a different speed relative to another of the plurality of tractor belts to locally control the density of the plurality of portions of the strip of filaments across the width of the polymer filament strip.

Brief Description of the Drawings

[0006]

Figure 1

Figure 2

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Embodiments for Carrying Out the Invention

[0007] Here, the embodiments are referred to in detail. Examples of the embodiments are shown in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the various embodiments described. However, it will be apparent to those skilled in the art that the various embodiments described may be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits, and networks have not been described in detail so as not to unnecessarily obscure aspects of the embodiments.

[0008] It should be understood that the disclosed embodiments are merely exemplary and that various alternative forms are possible. The figures are not necessarily to scale, and some features may be exaggerated or minimized to show details of particular components. Accordingly, the specific structural and functional details disclosed herein should not be construed as limiting, but rather as a representative basis for teaching one skilled in the art how to variously employ the embodiments of the present disclosure.

[0009] "One or more" includes a function performed by one element, a function performed by two or more elements, for example, in a distributed form, some functions performed by one element, some functions performed by some elements, or any combination of the above.

[0010] Terms such as first, second, etc. are used herein in some examples to describe various elements, but it should also be understood that these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of the various embodiments described, the first contact may be referred to as the second contact, and similarly, the second contact may be referred to as the first contact. The first contact and the second contact are both contacts, but they are not the same contact.

[0011] The terms used in the description of the various embodiments described herein are for the purpose of describing particular embodiments only and are not intended to be limiting. When used in the description of the various embodiments described and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the term "and / or" refers to any and all possible combinations of one or more of the associated listed items and is to be construed as inclusive. The terms "includes", "including", "comprises", and / or "comprising", when used herein, specify the presence of the stated feature, integer, step, operation, element, and / or component, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0012] Referring to FIG. 1, an extrusion line 10 for forming a preform strip of polymer filaments 20 is schematically shown. An extruder 12 receives resin beads 16 from a resin hopper 14, and the resin beads 16 are melted within the extruder 12 and then supplied to a die head 38 . The die head 18 extrudes polymer filaments 18 , which are then supplied through a forming funnel 20 . The forming funnel 22 deposits the polymer filaments 22 into a cooling tank 20 . The polymer filaments 24 are drawn into the cooling tank 20 by a tractor section 26 at a controllable speed. As the preform strip 24 is drawn into the cooling tank 38 , the polymer filaments 24 are first cooled in the cooling tank 20 24 ​It is cooled by the water inside and thus welded to each other. Cooling tank 24 The rollers inside 28 further draw the preform strip 38 into the further cooling tank 24 Shaker table 30 vibrates the preform strip 38 to remove water from the preform strip 38 while the unload conveyor 32 unloads the preform strip 24 from the cooling tank 38 Return water tank 34 collects water when water is discharged from the preform strip 38 The blower 36 is directed onto the return water tank 24 to cool the water when the water returns to the cooling tank 34

[0013] Polymer filaments 20 are welded, glued, or melted and include strands, fibers, or strips reformed into a three-dimensional mesh structure 38 The preform strip 38 includes an intermediate preform for manufacturing a plurality of vehicle seat pads that are later cut into individual sheet pads and formed into a predetermined shape

[0014] Polymer resin 16 is supplied to the resin hopper 14 in the form of resin beads or shredded polymer resin and includes LLDPE or HDPE

[0015] Cooling tank 24 is filled with water or a cooling aqueous solution for the polymer

[0016] The tractor section 26 described in more detail below 20 is in the longitudinal direction, which is the extrusion direction in which the polymer strands 18 flow from the die head 22 and the forming funnel​20 Subtract.

[0017] Referring to FIG. 2, the tractor section shown in FIG. 1 26 is shown to include a plurality of tractor belts 40a - 40e that are controlled to move relative to each other at variable speeds, thereby forming zones or regions having different hardness characteristics. In FIG. 2, a sheet base image 42 is superimposed on the drawing of the tractor belts 40a - 40e. The sheet base image 42 represents the sheet that is formed when the preform strip 38 is cut into individual sheet pad pieces and then formed in - mold into the illustrated sheet pad shape.

[0018] The sheet pad image 42 shown by the phantom line includes a first hardness zone 44 and a second hardness zone 46. A first boundary 48 is formed between the first hardness zone 44 and the second hardness zone 46. A third hardness zone 50 and the second hardness zone 46 form a second boundary 52 therebetween. As shown in FIG. 2, the first boundary 48 and the second boundary 52 are not perpendicular to the longitudinal or extrusion direction in which the belts move. Instead, they converge from the front portion of the sheet base image 42 to the rear portion of the sheet base image 42.

[0019] It should be understood that the boundaries 48 and 52 can be curved or arranged at a wide variety of angular orientations relative to the longitudinal direction to provide the desired change in the hardness profile in a given zone or region of the formed sheet cushion. The first boundary 48 and the second boundary 52 can extend completely across the preform strip 38 or can extend partially across the preform strip 38 Alternatively, the boundaries can be characterized as transition regions between different hardness zones.

[0020] The various tractor belts 40a - 40e are the preform strip 38A first velocity arrow 54 that schematically shows different velocities acting thereon is shown at the feeding end of the tractor belt section 26. The magnitude of the first velocity arrow 54 corresponds to the velocity at which each tractor belt moves.

[0021] A second velocity arrow 56 is shown above the first velocity arrow 54 in FIG. 2, and at a later time, the apparent / bulk density of the preform strip 38 is represented by a change in the velocities of the tractor belts 40a - 40e to locally change the apparent / bulk density. Similarly, a third velocity arrow 58 shown above the second velocity arrow 56 in FIG. 2 indicates that additional velocity changes can be made to change the apparent / bulk density of the preform strip 38 again. The length of each velocity arrow 54、56,58 changes to indicate that the relative velocities of the tractor belts 40a - 40e change as the polymer filament 20 is drawn through the tractor section 26.

[0022] The apparent / bulk density of the pad is controlled by the tractor belts 40a - 40e. The apparent / bulk density is not the same as the filament density which is the density of a single strand. The spacing between the strands is controlled by the velocity at which the tractor belts 40a - 40e draw the strands into the cooling tank 24 or the water tank. The apparent / bulk density in each zone of the sheet base increases as the velocity of the tractor conveyor belts 40a - 40e decreases. Conversely, the apparent / bulk density in each zone of the sheet base decreases as the velocity of the tractor conveyor belts 40a - 40e increases. There is an upper limit to the difference in velocity differences regarding how fast adjacent tractor belts can move. If the velocity difference is too large, a portion of the filament may be over - stretched, broken, thinned, or lose its bonding position. The degree of variation in the apparent / bulk density of the cushion is limited but can approach a 60% variation from one zone to another.

[0023] Motors 60a - 60e are variable speed motors controlled by a controller 62. The controller 62 is programmed to individually vary the speed of the motors and the movement of the tractor belts 40a - 40e so as to match or correspond to the specified apparent / bulk density of the zones of the seat cushion to be manufactured.

[0024] Referring to 5 Figure 38 the preform strip 38 is shown in cross - section across the width of the preform strip 38 to show the change in apparent / bulk density across the preform strip. Different apparent / bulk densities are indicated by relative looseness and compacting in different zones.

[0025] Referring to 3 Figure 4 and Figure 3 sheet backrest 64 is shown in Figure 4 and seat cushion 66 is shown in Figure 3 which include a soft zone or region 68 and three different hard zones or regions 70, 72, and 74 of different hardness values. The hardness of the soft zone is, for example, 1.2 kPA and the apparent / bulk density is 1.8 kg / m 3 The three different hard zones have hardnesses in the range of 1.2 kPA - 23.1 kPA and apparent / bulk densities in the range of 1.8 kg / m 3 - 5.8 kg / m.

[0026] Referring to Figure 6, a vehicle seat assembly 80 comprising a seat frame 76, a seat cover 78, a seat backrest cushion 64, and a seat base cushion 66 is shown. The seat frame 76 and seat cover 78 are provided in a wide range of styles and designs. The seat backrest cushion 64 and seat base cushion 66 are polymer filaments initially formed in a preform strip 38 and the preform strip 38is divided into separate cushions or seat pads and formed before being assembled into a vehicle seat assembly 80 The preform strip 38 is divided into a plurality of seat back cushions 64 or seat base cushions 66 that are each assembled to one of a plurality of seat frames 76 and covered by one of a plurality of seat covers 78.

[0027] The article has a body 38 comprising a plurality of extruded polymer filaments 20 of Preform strip, that is which are randomly oriented and joined to each other to form a three-dimensional mesh structure 38 and Preform strip 38 comprises a first zone 42 including extruded polymer filaments 20 that are elongated in a longitudinal direction and have a first apparent / bulk density, and a second zone 46 including extruded polymer filaments 20 that have a second apparent / bulk density that is less than the first apparent / bulk density.

[0028] The article described in the preceding paragraph can include one or more of the following additional features.

[0029] The article according to one or more of the above clauses comprises a first zone 42 and a second zone 44, and the first zone 42 and the second zone 44 define at least one boundary 48 or transition region between the first zone 42 and the second zone 44 that extends at least partially across Preform strip 38 The article according to one or more of the above clauses comprises a first zone 42 and a second zone 44, and the first zone 42 and the second zone 44 define at least one boundary 48 between the first zone and the second zone that extends completely across

[0030] The article according to one or more of the above clauses comprises a first zone 42 and a second zone 44, and the first zone 42 and the second zone 44 define at least one boundary 48 between the first zone and the second zone that extends completely across Preform strip 38 The article according to one or more of the above clauses comprises a first zone 42 and a second zone 44, and the first zone 42 and the second zone 44 define at least one boundary 48 between the first zone and the second zone that extends completely across

[0031] The article according to one or more of the above clauses has a body 38Comprises at least one boundary 48 between a first zone 42 and a second zone 44 that extends at an angle less than perpendicular to the longitudinal direction in which it moves.

[0032] An article according to one or more of the above paragraphs comprises at least one curved boundary 48 between a first zone 42 and a second zone 44.

[0033] An article according to one or more of the above paragraphs comprises a plurality of connected intermediate preforms 38 including Preform strip 38 and each of the intermediate preforms 38 is separated and adapted to be formed into seat cushions 64, 66.

[0034] The seat assembly 80 comprises a seat frame 76 and a seat cover 78 and a seat back cushion 64 and a seat base cushion 66. The body 38 comprises a plurality of extruded polymer filaments 38 that are randomly oriented and joined to each other to form an intermediate preform 20 and the intermediate preform 38 comprises a first zone 44 of extruded polymer filaments having a first apparent / bulk density 20 and a second zone 46 of extruded polymer filaments having a second apparent / bulk density that is less than the first apparent / bulk density 20 and the intermediate preform 20 is formed into a molded back cushion 64 and a seat base cushion 66. 38

[0035] The seat assembly described in the preceding paragraph can include one or more of the following additional features.

[0036] A seat assembly according to one or more of the above paragraphs comprises a first zone 42 and a second zone 44, and the first zone 42 and the second zone 44 are the body 38 ​defines at least one boundary 48 or transition region between a first zone 42 and a second zone 44 that extends at least partially across.

[0037] A sheet assembly according to one or more of the above items comprises a first zone 42 and a second zone 44, and the first zone 42 and the second zone 44 38 define at least one boundary 48 between the first zone 42 and the second zone 44 that extends completely across the body.

[0038] A sheet assembly according to one or more of the above items comprises at least one curved boundary 48 between the first zone 42 and the second zone 44.

[0039] The method includes melting a polymer resin 16 to form a molten polymer, extruding the molten polymer through a die head 18 to form an extruded polymer filament 20 and shaping and bonding the extruded polymer filament 20 into a strip of filaments having a predetermined cross-section. This method uses a plurality of tractor belts 40a - 40e arranged transversely to the longitudinal direction to draw a strip of filaments 20 into a cooling tank 20 24 38 longitudinally, and each of the tractor belts 40a - 40e moves one of a plurality of portions of the strip of filaments 20 longitudinally. The plurality of tractor belts 40a - 40e are controlled to move one of a plurality of portions of the strip of filaments at a different speed relative to other tractor belts of the plurality of tractor belts 40a - 40e, locally controlling the apparent / bulk density of the plurality of portions of the strip of filaments 20 across the width of the strip of polymer filaments 20

[0040] ​​​The method described in the preceding paragraph can include one or more of the following additional features.

[0041] Upper The method by one or more of the clauses further includes cutting filaments in a direction transverse to the longitudinal direction to form a plurality of sheet cushion preforms 64, 66. 20 of the strip.

[0042] Upper By one or more of the clauses Method further includes shaping a plurality of sheet pad preforms 64, 66 into the contour shape of a sheet cushion.

[0043] Upper By one or more of the clauses Method in which the 16 polymer resin is a thermoplastic polymer such as LLDPE or HDPE.

[0044] Upper By one or more of the clauses Method further includes assembling a strip of filaments including sheet pads 64, 66 to a sheet frame. 38

[0045] Upper By one or more of the clauses Method further includes covering the sheet pads 64, 66 with a sheet cover.

[0046] A sheet assembly by one or more of the above clauses is manufactured according to the method.

[0047] Exemplary embodiments have been described above, but these embodiments are not intended to describe all possible forms according to the present disclosure. In that regard, the terms used in this specification are terms for explanation rather than limitation, and it is understood that various modifications can be made without departing from the spirit and scope of the present disclosure. Furthermore, the features of various embodiments can be combined to form further embodiments according to the present disclosure.

Claims

1. 1. An article comprising a body of a plurality of extruded polymer filaments randomly oriented and joined together to form a three-dimensional mesh structure, the body being elongated in a longitudinal direction and including a first zone comprising the extruded polymer filaments having a first density and a second zone comprising the extruded polymer filaments having a second density less than the first density.

2. 2. The article of claim 1, wherein the first zone and the second zone define at least one boundary between the first zone and the second zone that extends at least partially across the body.

3. The article of claim 2 , wherein the at least one boundary between the first zone and the second zone is curved.

4. The article of claim 2 , wherein the at least one boundary between the first zone and the second zone extends at an angle less than perpendicular to the longitudinal direction.

5. 2. The article of claim 1, wherein the first zone and the second zone define at least one boundary between the first zone and the second zone that extends completely across the body.

6. The article of claim 1 , wherein the body comprises a plurality of intermediate preforms, each of the intermediate preforms adapted to be separated and molded into a seat cushion.

7. Seat frame and Seat covers and a body including a plurality of extruded polymer filaments randomly oriented and joined to one another to form an intermediate preform, the intermediate preform including a first zone of the extruded polymer filaments having a first density and a second zone of the extruded polymer filaments including the extruded polymer filaments having a second density lower than the first density, the intermediate preform being molded to form a molded seat cushion; A seat assembly comprising:

8. 8. The seat assembly of claim 7, wherein the first zone and the second zone define at least one boundary between the first zone and the second zone that extends at least partially across the body.

9. 8. The seat assembly of claim 7, wherein the first zone and the second zone define at least one boundary between the first zone and the second zone that extends completely across the body.

10. 10. The seat assembly of claim 9, wherein the at least one boundary between the first zone and the second zone is curved.

11. melting a polymer resin to form a molten polymer; extruding the molten polymer through a die head to form an extruded polymer filament; forming and joining the extruded polymer filaments into a strip of filaments comprising a predetermined cross-section; pulling the strip of filament in a longitudinal direction into a cooling bath using a plurality of tractor belts arranged transversely to the longitudinal direction, each of the tractor belts moving one of a plurality of portions of the strip of filament in the longitudinal direction; controlling the plurality of tractor belts to move one of the plurality of portions of the strip of filament at a different speed relative to other tractor belts of the plurality of tractor belts to locally control a density of the plurality of portions of the strip of filament across a width of the strip of polymer filament; A method comprising:

12. The method of claim 11 , further comprising cutting the strip of filaments transversely to the longitudinal direction to form a plurality of seat pad preforms.

13. The method of claim 12, further comprising forming the plurality of seat pad preforms into a contoured shape of a plurality of seat pads.

14. The method of claim 13 , further comprising assembling each of the plurality of seat pads to one of a plurality of seat frames.

15. The method of claim 13, further comprising covering each of the plurality of seat pads with one of a plurality of seat covers.

16. The method of claim 11 , wherein the polymer resin is HDPE.

17. The method of claim 11 , wherein the polymer resin is a thermoplastic polymer.

18. The method of claim 11 , wherein the polymer resin is LLDPE.

19. A strip of polymer filaments produced according to the method of claim 11.

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