SUSPENSION FABRIC SEAT HEATING SYSTEM

Abstract

A method for making a seat includes the step of overmolding a carrier onto a fabric seat surface. The fabric surface is formed from a woven fabric material having heating element fibers. The heating element fibers are placed in contact with a conductor. The carrier and the conductor are then positioned into a frame.

Claims

1. A method for making a seat, comprising: overmolding a carrier onto a fabric seat surface formed from a woven fabric material having heating element fibers; contacting the heating element fibers with a conductor; and positioning the carrier and the conductor in a frame.

2. The method of claim 1, wherein the carrier is positioned in a channel in the frame.

3. The method of claim 1, wherein the conductor is positioned in a channel in the frame.

4. The method of claim 2, wherein the conductor is positioned in the channel.

5. The method of claim 2, wherein the conductor uses a conductive thermoplastic, and the heating element fibers is connected to the conductive thermoplastic.

6. The method of claim 5, wherein the overmolding of the carrier onto the fabric seat surface further comprises: applying a first application of the conductive thermoplastic; and laying the heating element fibers into the conductive thermoplastic.

7. The method of claim 6, wherein the overmolding of the carrier onto the fabric seat surface further comprises: applying a second application of a non-conductive thermoplastic that includes molding over the heating element fibers and the conductive thermoplastic.

8. The method of claim 7 further comprising: positioning the carrier into the channel in the frame after the step of applying the second application.

9. The method of claim 1 further comprising: applying a powdered metal to the woven fabric material.

10. The method of claim 9, wherein overmolding the carrier onto the fabric seat surface further comprises: providing a non-conductive thermoplastic.

11. The method of claim 2 further comprising: providing a carrier mold tool, wherein the step of overmolding the carrier onto the fabric seat surface further comprises: providing a conductive foil element, and positioning the conductive foil element into the carrier mold tool prior to the step of positioning the woven fabric material into the carrier mold tool.

12. The method of claim 11, wherein the overmolding of the carrier onto the fabric seat surface further comprises: providing a non-conductive thermoplastic, wherein the step of overmolding creates an injection pressure, and wherein the injection pressure presses the heating element fibers onto the conductive foil element to form the conductor.

13. The method of claim 12 further comprising: positioning the carrier into the frame after the step of applying the non-conductive thermoplastic onto the heating element fibers.

14. The method of claim 1, wherein the step of overmolding the carrier onto the fabric seat surface further comprises: providing a carrier mold tool; and providing a conductive adhesive, wherein overmolding the carrier onto the fabric seat surface further comprises: applying the conductive adhesive into the carrier mold tool, and loading the woven fabric material into the carrier mold tool after applying the conductive adhesive into the carrier mold tool.

15. The method of claim 14 further comprising: providing a non-conductive thermoplastic, wherein overmolding the carrier onto the fabric seat surface further comprises applying the non-conductive thermoplastic, and wherein applying the non-conductive thermoplastic creates an injection pressure, and the injection pressure presses the heating element fibers onto the conductive adhesive to form the conductor.

16. The method of claim 14 further comprising: providing a non-conductive thermoplastic, wherein overmolding the carrier onto the fabric seat surface further comprises applying the non-conductive thermoplastic, wherein applying the non-conductive thermoplastic creates heat, and wherein the heat cures the conductive adhesive to wet out onto the heating element fibers to form the conductor.

17. The method of claim 1, wherein the conductor is a conductive strip, and wherein the method for making a car seat further comprises: providing a strip socket, and positioning the conductive strip in the strip socket.

18. The method of claim 17 further comprising: capturing at least one of the heating element fibers between the strip socket and the conductive strip.

19. A method for making a seat, comprising: cutting a woven fabric with heating element fibers having an insulative coating to define a shaped fabric; inserting the shaped fabric into a carrier mold; and overmolding the shaped fabric with a polymeric material; wherein the overmolding step bonds the polymeric material to the heating element fibers by a mechanical bonding as well as a chemical bonding, wherein the polymeric material and the woven fabric form a carrier, and wherein the carrier and the woven fabric form a carrier assembly.

20. The method of claim 19 further comprising: removing the insulative coating from the heating element fibers that are outside an outer edge of the carrier assembly.

21. The method of claim 20 further comprising: providing a frame having a frame channel, and installing the carrier assembly into the frame channel, wherein the carrier forms a conductor.

22. The method of claim 21 further comprising: providing a connector within the frame channel, wherein the conductor electrically connects to the connector.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The benefits and advantages of the present embodiments will become more readily apparent to those of ordinary skill in the relevant art after reviewing the following detailed description and accompanying drawings, wherein:

[0021] FIG. 1 is an example of a suspension seat fabric in accordance with the present disclosure;

[0022] FIG. 2 illustrates an embodiment of a seat bottom surface in a seat surface carrier in accordance aspects of the present disclosure;

[0023] FIGS. 3A and 3B illustrate the basic construction of an embodiment of the seat bottom in an assembled view (FIG. 3A) and in an exploded view (FIG. 3B), showing the seat bottom surface in the carrier, the conductor and the seat frame;

[0024] FIG. 4 is an illustration of an embodiment of a seat surface showing the heating element fibers or electrical conductive wires woven into the fabric;

[0025] FIG. 5 illustrates a conductive strip and strip socket;

[0026] FIG. 6 is a perspective view of the strip socket;

[0027] FIG. 7 shows the conductive strip and the socket in position on opposite sides of the heating element fibers;

[0028] FIG. 8 illustrates the conductive strip and feed socket as the conductive strip is positioned for insertion into the strip socket with the captured heating element fibers;

[0029] FIG. 9 illustrates trimming of the heating element fibers after the conducting strip and strip socket are engaged with the heating element fibers;

[0030] FIG. 10 illustrates two ways in which the conductive strip and strip socket (with the captured heating element fibers) can be mounted to the seat frame;

[0031] FIGS. 11A-11C are detailed views of the construction of an embodiment of the seat bottom, illustrating various routings of the conductor and an electrical connector;

[0032] FIGS. 12A-12D show various examples of constructions of the heating element fibers in the seat frame; and

[0033] FIG. 13 is a flow diagram of a method for fabricating the suspension fabric seat and heating system in accordance with the present disclosure.

DETAILED DESCRIPTION OF THE DRAWINGS

[0034] While the present disclosure is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described one or more embodiments with the understanding that the present disclosure is to be considered illustrative only and is not intended to limit the disclosure to any specific embodiment described or illustrated.

[0035] Referring to the figures and in particular to FIG. 1, there is shown an example of a woven fabric 10 for a suspension fabric seat surface 12. The fabric 10 is woven from fibers or yams (used interchangeably herein) and includes a series of warp fibers 14, illustrated as the vertical fibers, and weft fibers 16 illustrated as the horizontal fibers. Typically, the warp fibers 14 are fill yarns and extend in the front-to-rear direction of a seat bottom surface or a top-to¬bottom direction in a seat back surface or headrest. The weft fibers 16 are typically monofilament fibers that extend in a side-to-side direction transverse to the warp fibers 14. An example of a woven fabric is disclosed in Coffield, U.S. Pat. No. 8,329,281, which patent is commonly assigned with the present application, the disclosure of which is incorporated herein in its entirety. Examples of the monofilament fibers are disclosed in Coffield, et al., U.S. Pat. No. 8,857,033 and Coffield, U.S. Pat. No. 9,156,211, which patents are commonly assigned with the present application, the disclosures of which are incorporated herein in their entirety.

[0036] The warp fibers 14 or yams are relatively inelastic and elongate less than about 12 to 15 percent and preferably, less than about 5 percent. The warp fibers 14 give the fabric 10 bulk and thickness and are able to be colored for a colored fabric suspension assembly. The warp fibers 14 are used to shape the seat surface 12 by pulling the monofilament (weft) fibers 16 out of straight line position to form a parabolic shape in the overall suspension fabric seat surface 10. The warp fibers 14 can be formed from, for example, a polyester yarn or like, suitable materials.

[0037] The weft fibers 16 are typically elastic and can be formed from, for example, a block copolymer monofilament. These fibers 16 can be orientated and elongate more than 10 percent, and up to about 30 percent when measured on a stress strain curve. The monofilament weft fibers 16 can be oriented and conditioned (as at an elevated temperature) and can be treated zonally to obtain a desired occupant pressure map of the seat shape making the seat more comfortable.

[0038] As seen in FIG. 1, heating elements fibers or conductive wires 18 are interspersed with the warp fill fibers or yams 14. In embodiments, the heating element fibers 18 can replace all or some of the fill yams 14 or they can supplement the fill yarns 14. In embodiments, the heating element fibers 18 are semi-conductive with a targeted ohm resistance to achieve a temperature of about 30° C. to about 50° C. when powered. Some examples of heating element fibers 18 are coated stainless steel wire, copper, nano-tube materials such as nano-tube polyester, carbon yams, and the like. Other suitable heating element fibers 18 will be recognized by those skilled in the art. In some embodiments, some of the weft fibers 14 may include or be replaced by or supplemented with heating element fibers 18 as well.

[0039] As noted above, in an embodiment, the heating element fibers 18 are woven in place of some of warp fibers or yams so as to limit that amount of added bulk and thickness, and to reduce the visual and aesthetic impact on the seat surface 12. It will be appreciated that the heating element fibers 18 can be affixed to the bottom of the seat surface 12 as well, by, for example, stitching, adhesives and the like. In some embodiments the heating element fibers 18 can be woven into the fabric 10 having some amount of slack, as indicated at 11 in FIG. 4. As will be appreciated by those skilled in the art, the heating element fibers 18 may be formed from materials that are less elastic than either or both of the warp and weft fibers. As such, in order to allow the heating element fibers 18 to conform to the seat surface 12 as the seat surface 12 conforms to a user's body, slack 11 in the heating element fibers 18 permits such conformance while preventing overstressing or overstretching the heating element fibers 18.

[0040] Referring to FIGS. 4-10, in an embodiment, the heating element fibers 18 are secured to a conductive member 19, such as a highly conductive strip. The heating element fibers 18 can be secured to the conductive strip 19 in a wide variety of ways. For example, a coating on the heating element fibers 18 can be removed and the bare heating element fibers 18 can be soldered or otherwise adhered to the conductive strip. In an embodiment, as illustrated in FIGS. 5-8, the heating element fibers 18 can be captured between the highly conductive strip 19 and a receiving element 21 configured to receive the heating element fibers 18 and the conductive strip 19, such as the illustrated conductive strip socket 21. In such an embodiment the conductive strip 19 and the strip socket 21 can be configured, for example, roughened, to strip or remove any coating from the heating element fibers 18 as the conductive strip 19 is inserted into the strip socket 21 with the heating element fibers 18 captured therebetween. Such an arrangement serves to provide the necessary electrical contact between the heating element fibers 18 and the conductive strip 19.

[0041] The woven fabric 10 is overmolded with a carrier 22. The fabric 10 is installed into a carrier mold and the fabric 10 is overmolded with the carrier 22 material. A carrier 22 material can be, for example, a block copolymer that is chemically similar to the fabric 10 monofilaments (the weft fibers 16). This permits chemical bonding during the injection mold process. Mechanical bonding also takes place during overmolding. Preferably, the heating element fibers 18 in the fabric 10 are designed as a parallel circuit for heating efficiency and robustness.

[0042] FIG. 2 illustrates an embodiment of a seat bottom surface 12 with a carrier 22 overmolded onto the seat surface fabric 10. In the illustrated embodiment, the seat bottom surface 12 and carrier 22 are shown with the heating element fibers 18 on either side of, and outside of the carrier 22. In an embodiment, the heating element fibers 18 are woven into the fabric 10, as illustrated in FIG. 1. In FIG. 2, the heating element fibers 18 are visible where the fibers 18 extend beyond the carrier periphery 50. The heating element fibers 18 are continuous (to both sides of the seat and into the carrier 22) to complete the electrical circuit. The heating element fibers 18 can be located in the seat surface 12 so as to minimize wear.

[0043] In the embodiment illustrated in FIG. 10, the heating element fibers 18 do not extend beyond, and are not molded into, the carrier 22. Rather, the heating element fibers 18 are captured and pinched between the conductive strip 19 and the strip socket 21 within the perimeter or bounds of the carrier 22.

[0044] It will be understood that some types of heating element fibers 18 may be coated fibers and that coated fibers 18, such as coated stainless steel fibers, have the coating removed so that an electrical circuit can be completed. Removal of the coating can be, for example, by burnishing the ends of the fibers 18, abrading during installation (as in the heating element fibers 18 and configuration of FIGS. 4-10), heating or other methods that will be recognized by those skilled in the art. Removing the coating exposes the conductive core of the heating element fibers 18.

[0045] FIGS. 3A and 3B illustrate assembled and exploded views, respectively, of an embodiment of the seat surface 12 and carrier 22, the conductor 24 and the frame 26. The conductor 24 is shown as a separate component, but as described herein in connection with certain embodiments, the conductor 24 may be incorporated into the carrier 22. In an embodiment, the conductor 24 is disposed in a channel 28 formed in the frame 26. A connector 30, shown in an exploded position, is electrically connected to the conductor 24 to provide power and control to the heating elements fibers 18. FIGS. 11A-11C illustrate the negative and positive sides 32, 34, respectively, of the conductor 24 as it is disposed in the channel 28 and the electrical connector 30. The connector 30 is shown in both front and rear views of the frame 26.

[0046] FIG. 10 illustrates two ways in which the seat surface 12, carrier 22 and conductor/heating element fibers (the conductive strip 19 and the strip socket 21 with the captured heating element fibers 18) can be installed in the frame 26. On the left-hand side of FIG. 10, the conductive strip 19/heating element fibers 18/strip socket 21 and the carrier 22 are installed in a common channel 28 in the frame, and both are press fit into the channel 28 in the frame 26. On the right-hand side of FIG. 10, the conductive strip 19/heating element fibers 18/strip socket 21 is installed in a conductor channel 28′ in the frame 26, and the carrier 22 is installed in a carrier channel 28 in the frame 26, separate from the conductor channel 28′. The conductive strip 19/heating element fibers 18/strip socket 21 and the carrier 22 can be press fit into the channel 28/28′. Other ways in which the conductive strip 19/heating element fibers 18/strip socket 21 and carrier 22 are secured in the frame 26 will be recognized by those skilled in the art. Once installed and secured in the frame 26, electrical connection, for example, power and control can be provided to the conductive strip 19/heating element fibers 18/strip socket 21 as illustrated in FIGS. 11A-11C.

[0047] In embodiments, temperature measurement or sensing is provided in the heating system. Referring briefly again to FIG. 1, in an embodiment, a sensor, such as a temperature sensor is provided in the form of one or more fibers 31. The temperature sensor fiber 31 can be, for example, a thermocouple fiber that is incorporated into the seat surface 12, for example along with the weft or mono¬filament fibers 16. It will be appreciated that the temperature sensor fiber 31 can also be incorporated along with the warp fibers 14, or as another fiber. As such, the temperature sensor fiber 31 can be fabricated to have characteristics similar to those fibers 14 or 16 around which it is incorporated into the seat surface 12. The temperature sensor fiber 31 may be incorporated into the seat heating system along with a switch to provide, isolate or vary power to the heating element fibers 18. Other sensors for temperature measurement may also be used, which other sensors are within the scope and spirit of the present disclosure. It is contemplated that the heating element fibers 18 can be individually controlled or monitored, or can be controlled in groups as well as being controlled as one.

[0048] FIGS. 12A-12D illustrate various examples of ways in which the heating element fibers 18 as positioned in and extending through the carrier 22, can be electrically connected to the connector 30, through the frame 26. [0058] FIG. 12A illustrates a conductor 24 that uses a conductive thermoplastic 36 to which the heating element fiber 18 ends are connected. In an embodiment, the conductive thermoplastic 36 is part of the carrier 22 overmold. That is, a first shot or application of the carrier 22 overmold material is the conductive thermoplastic 36 with the exposed fibers 18 laid into the conductive thermoplastic 36. A second shot of a non-conductive thermoplastic 38 is molded over the fiber 18 ends and the conductive thermoplastic 36 to seal the fiber 18 ends and form a seat surface/carrier assembly 48. The seat surface/carrier assembly 48 is then positioned in the frame channel 28.

[0049] In FIG. 12B, a powdered metal 40 is applied to the fabric 10 and the carrier 22 is overmolded onto the fabric 10 and the powdered metal 40. The powdered metal 40 bridges the spaces between the fibers 18, and the injection pressure during the carrier 22 overmolding wets out the powdered metal 40 to form the conductor 24. The seat surface/carrier assembly 48 is then positioned in the frame channel 28.

[0050] In FIG. 12C, a conductive foil element 42, such as a metal foil strip is positioned in the carrier mold tool prior to positioning the fabric 10 in the mold tool. The carrier 22 overmolding presses the foil 42 on to the heating element fiber 18 ends to form the conductor 24, and the seat surface/carrier assembly 48 is then positioned in the frame channel 28.

[0051] In FIG. 12D, a conductive adhesive 44 is used. In this embodiment the conductive adhesive 44, such as a conductive epoxy which can be applied, for example, in strip form, is positioned in the carrier tool before the fabric 10 is loaded. In the molding process, the injected carrier resin flows over the heating element fiber 18 ends and the adhesive 44, and the injection pressure and resin heat cure the adhesive 44 and wet out onto heating element fiber 18 ends and the fabric 10 to form the conductor 24. Other suitable conductive adhesives 44 will be recognized by those skilled in the art.

[0052] It will be appreciated that in each of the embodiments disclosed, the conductor 24, whether separate from or formed as part of the carrier 22, is reliably electrically attached to each of the heating element fibers 18 across the entirety of the seat surface 12. It is anticipated that about 2 to 30 yams, spaced about 10 to 30 mm apart will provide the desired level of heating. The carrier 22 overmold holds the fabric 10 in tension, and also conceals the conductive path, e.g., the conductor 24, from the heating element fibers 18 up to termination at the electrical terminal connector 30.

[0053] One method 100 for making the suspension fabric seat heating system is illustrated in FIG. 13, and includes, at step 102, cutting a woven fabric 10 as needed and positioning the woven fabric 10 (with the heating element fibers 18 in the fabric 10) in a carrier 22 mold at step 104. The carrier 22 is overmolded onto the fabric 10 at step 106 with a block copolymer or other suitable polymeric material. Preferably, the carrier overmold material is chemically similar to the fabric monofilaments (for example, the weft fibers 16) so that chemical, as well as mechanical bonding occurs during the injection molding process.

[0054] In a method, the carrier 22 overmold is carried out in a two shot or two application process. In a first shot, the overmold material is a conductive thermoplastic 36. The fabric 10 with the heating element fibers 18 is then laid onto the conductive thermoplastic 36 and a second shot of a non-conductive thermoplastic 38 is laid over the fabric 10 and the conductive thermoplastic 36.

[0055] In another method, the carrier 22 overmold is also carried out in a two shot or two application process. In a first shot, the overmold material is a non-conductive thermoplastic 38. A powdered metal 40 is applied to the fabric 10 and the fabric 10 and powdered metal 40 are laid onto the non-conductive thermoplastic 38. A second shot of nonconductive thermoplastic 38 is laid over the fabric 10 and metal 40, and the first shot of non-conductive thermoplastic 38.

[0056] In still another method, the carrier 22 overmold is carried out in a one shot or application process. A conductive element 42, such as a metal foil or strip is positioned in the overmold tool, and the fabric 10, with the heating element fibers 18 is laid onto the element 42. A non-conductive thermoplastic 28 is laid over the fabric 10 and the element 42.

[0057] In yet another method, the carrier 22 overmold is carried out in a two shot or two application process with the fabric 10 sandwiched between two applications of non-conductive thermoplastic 38 to form the carrier 22. The heat element fiber 18 ends are exposed beyond the carrier outer periphery 50. A conductive adhesive 44 is applied to an outer surface of the carrier 22 or the bottom of the frame channel 28 so as to make contact with the heat element fiber 18 exposed ends.

[0058] Once the fabric or seat surface/carrier assembly 48 is formed, in a post processing step at step 108, any insulative coating is removed from the heating element fibers 18 outside of the overmolded fabric/carrier assembly 48. The insulative coating, if present, can be removed by burnishing, heating or other suitable methods to expose the conductive core of the heating element fibers 18. If necessary, the carrier 22 and fabric 10 can be trimmed to remove excess polymer beyond the carrier outer periphery 50 for better quality and fit into the frame 26. In some methods, a small amount of fabric 10 with the exposed heating element fiber 18 ends remains beyond the carrier outer periphery 50. The frame 26 is molded so as to receive the seat surface/carrier assembly 48. In embodiments, the frame 26 is with the channel 28 and, depending upon which configuration of fabric/carrier assembly 48 is used, the conductor 24 may be applied or installed in the channel 28, preferably in the bottom of the channel 28, or the fabric/carrier assembly 48 which incorporates the conductor 24, is installed directly into the channel 28, as at step 110.

[0059] In a method, the burnished ends of the heating element fiber 18 are folded over the carrier 22 to expose the conductive fibers to the conductor 24, as needed, and the fabric/carrier assembly 48 is installed into the frame.

[0060] In still another method for making the suspension fabric seat heating system, the fabric 10 is woven (with the heating element fibers 18 in the fabric 10) such that the heating element fibers 18 do not extend to the edges of the fabric 10. The heating element fibers 18 may be woven into the fabric 10 with some slack. The heating element fibers 18 are captured between a conductive strip 19 and a strip receiver 21, such as the illustrated strip socket, on either side of the fabric 10. The carrier 22 is overmolded onto the fabric 10 outside of the conductive strip 19 and a strip receiver 21 with, for example, a block copolymer or other suitable polymeric material. Preferably, the carrier overmold material is chemically similar to the fabric monofilaments (for example, the weft fibers 16) so that chemical, as well as mechanical bonding occurs during the injection molding process.

[0061] The carrier 22, and the conductive strip 19 and strip receiver 21 with the captured heating element fibers 18, are then installed in the channel 28 in the frame 26. The conductive strip 19/strip receiver 21/captured heating element fibers 18 and the carrier 22 can be installed in common channels 28 or the conductive strip 19/strip receiver 21/captured heating element fibers 18 can be installed in one channel 28′ and the carrier in another channel 28.

[0062] Because the channel 28 or 28′ navigates around the frame 26 perimeter and terminates at the connector 30, preferably at a location hidden from occupant view and near the vehicle wire harness and wire harness terminal connector, there are few if any visible components to detract from the aesthetics of the seat. In addition, the configuration in which the conductive strip 19/strip receiver 21/captured heating element fibers 18 do not extend to and into the carrier, the channel 28 or 28′ can serve as a protective zone of the seat, free of occupant induced stresses and enhancing circuit robustness and the life span of the electronics.

[0063] The molded in electrical connector 30 ensures easy installation of power for the electrical circuit, and maintains a discrete appearance hidden from view within the seat frame assembly. The present configuration is sufficiently robust to withstand repeated loading by vehicle seat occupants.

[0064] In the present disclosure, the words “a” or “an” are to be taken to include both the singular and the plural. Conversely, any reference to plural items shall, where appropriate, include the singular. It will be appreciated by those skilled in the art that the relative directional terms such as upper, lower, rearward, forward and the like are for explanatory purposes only and are not intended to limit the scope of the disclosure.

[0065] All patents or patent applications referred to herein, are hereby incorporated herein by reference, whether or not specifically done so within the text of this disclosure.

[0066] From the foregoing it will be observed that numerous modification and variations can be effectuated without departing from the true spirit and scope of the novel concepts of the present film. It is to be understood that no limitation with respect to the specific embodiments illustrated is intended or should be inferred. The disclosure is intended to cover by the appended claims all such modifications as fall within the scope of the claims.