Abstract:
An interior panel, for use in a vehicle that includes a plurality of electrical devices and a vehicle component frame, includes printed electrical connection means for connecting the electrical devices in the vehicle and a substrate layer that has an inner surface directed towards the vehicle component frame. The electrical connection means are printed on the inner surface of the substrate layer using an electrically conductive ink.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of co-pending U.S. patent application Ser. No. 13/143,377 filed on Sep. 21, 2011, which is a national stage entry under 35 U.S.C. §371 of International Patent Application No. PCT/US2010/020090 filed Jan. 5, 2010, which claims priority to U.S. Provisional Patent Application No. 61/142,769 filed on Jan. 6, 2009, the entire contents of all of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to a roof structure, especially a vehicle overhead system including a headliner with an integral wire harness, a method for manufacturing this roof structure and a system comprising such a roof structure, a connector and a conductive pad. 
     BACKGROUND OF THE INVENTION 
     Many vehicle overhead systems include electrical wiring behind the vehicle headliner to provide power to and/or communication with various controls, such as, for example, garage door opener or compass, and/or features such as, for example, a dome light. With conventional overhead systems, standard wires such as, for example, stranded, insulated copper or other metallic wires are installed between the headliner and the vehicle roof. 
     Overhead systems are currently installed in motor vehicles in a series of steps at a plurality of stations on a vehicle assembly line. Individual overhead system components that require electricity as a power source or to provide a signal are individually connected to the vehicle body electrical system at the time of assembly. A wire harness, including all of the wiring necessary for the overhead system components, is attached to the back of the headliner with, for example, tape or hot melt glue. The various wires forming the wire harness are typically located between the headliner and the roof of the vehicle. When the wires are located between the headliner and the roof, they sometimes contact the roof structural supports. This contact between the wire and the roof structural supports may result in the wire being pinched, cut, or having the insulation rubbed off to cause a short circuit as the wire contacts the vehicle body. The insulation and/or other wrappings required for traditional wire harnesses also add significantly to headliner weight. 
     SUMMARY OF THE INVENTION 
     The invention provides, in one aspect, an interior panel for use in a vehicle that includes a plurality of electrical devices and a vehicle component frame. The interior panel includes printed electrical connection means for connecting the electrical devices in the vehicle and a substrate layer that has an inner surface directed towards the vehicle component frame. The electrical connection means are printed on the inner surface of the substrate layer using an electrically conductive ink. 
     The invention provides, in another aspect, a method for manufacturing an interior panel of a vehicle that includes a plurality of electrical devices. The method includes printing electrical connection means on the interior panel using an electrically conductive ink and piercing the interior panel with an electrical connector to connect one of the electrical devices to the electrical connection means. 
     The invention provides, in yet another aspect, a system including an electrical device and an interior panel with printed electrical connection means and a printed conductive pad. An electrical connector pierces through the interior panel to connect the electrical device with the conductive pad, and the electrical connection means are printed on the interior panel using an electrically conductive ink. 
     The invention provides, in a further aspect, an interior panel for use in a vehicle that includes a plurality of electrical devices and a vehicle component frame. The interior panel includes a printed wire harness for connecting the electrical devices in the vehicle and a substrate layer having an inner surface directed towards the vehicle component frame. The wire harness is printed on the inner surface of the substrate layer using an electrically conductive ink. 
     Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various exemplary embodiments of the systems and methods according to the present disclosure will be described in detail, with reference to the following figures, wherein: 
         FIG. 1  is a partial perspective view of the interior of a vehicle; 
         FIG. 2  is a top view of a first exemplary embodiment of a headliner substrate with an exemplary circuit on the headliner substrate according to this invention; 
         FIG. 3  is a top view of a first exemplary embodiment of a headliner according to this invention after being formed and trimmed, including the headliner substrate of  FIG. 2 ; 
         FIG. 4  is a top view of a headliner according to this invention; 
         FIG. 5  is a top view of an exemplary embodiment of a strain relief circuit according to this invention; 
         FIG. 6  is a partial cross-sectional view of a first exemplary embodiment of a headliner according to this invention taken along the line  6 - 6  in  FIG. 4 ; 
         FIG. 7  is a cross-sectional view of a second exemplary embodiment of a headliner according to this invention; 
         FIG. 8  is a top view of an exemplary embodiment of circuitry for a connection point according to this invention; 
         FIG. 9  is a cross-sectional view of a first exemplary embodiment of an electrical coupler according to this invention; 
         FIG. 10  is a cross-sectional view of a second exemplary embodiment of an electrical coupler according to this invention; 
         FIG. 11  is a perspective view of the electrical coupler shown in  FIG. 10 ; 
         FIG. 12  is a cross-sectional view of a third exemplary embodiment of an electrical coupler according to this invention; 
         FIG. 13  shows schematically a part of a roof structure according to the present invention; and 
         FIG. 14  shows schematically a further embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     In various exemplary embodiments, this invention relates to a overhead systems with a wire harness for electrically connecting to components integrated into the headliner. For example, the wire harness may be formed by printing the wiring or circuitry on part of the headliner core using a conductive ink and methods for making the same. The wiring or circuitry may be printed either before or after the overhead system is fully assembled. The wiring or circuitry may be printed in various parts of the overhead system, including, for example, on a scrim layer, on a substrate layer, or on a film attached to overhead systems. The overhead systems of this invention are produced at a lower cost, require less space, and weigh less than conventional overhead systems (e.g., headliners and wire harnesses) due to the reduced cost, size, and weight of the wire harness. 
     In various exemplary embodiments, the wire harness is incorporated into a film layer that is attached to or otherwise incorporated into the headliner. For example, the wire harness could be formed from flex circuits attached to an overhead systems component. 
       FIG. 1  shows a partial view of the interior of a vehicle. In particular,  FIG. 1  shows a portion of a headliner  100  adjacent to a front windshield. Various overhead system components are shown attached to or through the headliner  100 , such as, for example, various lights  120 , visors  130 , and hand grips  140 . Other components, such as, for example, a center overhead console, control buttons, etc. are also often attached to the headliner  100 . Many of these components require electrical power and/or communication with a control to function. This power and/or communication is typically supplied with wires located behind the headliner  100 . 
       FIG. 2  shows a first exemplary embodiment of a headliner substrate  101  with one exemplary embodiment of a printed wire harness  110  provided on the headliner substrate  101 . In various embodiments, the printed wire harness  110  is applied to the headliner substrate  101  using a conductive ink. The ink may be applied by any method including, for example, painting, screen printing, inkjet printing, pad printing, transfer printing, or any other known or later-developed method. Strain relief circuits  111  and conductive pads  112  are provided at several locations on the headliner substrate  101 .  FIG. 3  shows the headliner substrate  101  of  FIG. 2  after the headliner substrate  101  has been formed and trimmed to its final shape. 
       FIG. 4  shows another embodiment of a headliner  200  according to this invention. It should be noted that forming the headliner substrate  201  to its final shape can involve stretching all or part of the headliner substrate  201 . Stretching the substrate material underlying the wire harness  210  may result in breaks in the wire harness  210 . The wire harnesses  110  shown in  FIGS. 2 and 3 and 210  shown in  FIG. 4  include strain relief circuits  111  and  211  that will retain their integrity during and after the underlying headliner  201  substrate  101  are stretched.  FIG. 5  illustrates another embodiment of a strain relief circuit  311 . The curved strain relief circuit  311  shown in  FIG. 5  can withstand common amounts of stretching of the underlying headliner substrate  101  and/or  201  to which the headliner substrate  101  is subjected during installation without breaking the connection. Although  FIG. 5  shows the strain relief circuit  311  with dramatic switchback curves, narrower or shallower curves may be used, depending on the extent to which the headliner substrate  301  will be stretched during subsequent handling. As outlined above with respect to  FIGS. 2 and 3 , the strain relief circuits  111  can be provided at one or more locations on the headliner substrate  101 . 
     In various exemplary embodiments, the wire harness  210  may be located on various surfaces within a headliner  200 . In an exemplary embodiment, shown on  FIG. 6 , the wire harness  210  is placed on the B side of the headliner substrate  201  (i.e., the side of the substrate adjacent to the fabric layer). In another exemplary embodiment shown in  FIG. 7 , the wire harness  210  is placed on the C side of the headliner substrate  201  and covered by a scrim layer  202 , which may be used to insulate the wire harness  210  from contact with the vehicle body. In various other exemplary embodiments, the wire harness  210  may be covered and/or insulated by a thin film layer and/or a sprayed-on layer, rather than a scrim layer  202 . 
       FIG. 8  shows a section of a wire harness  410  according to this invention at a point in the headliner  400  where a headliner component is electrically connected to the wire harness  410 . As shown in  FIG. 8 , one or more conductive pads  412  are provided along the wire harness  410  at or near where the headliner component (not shown) will be attached to the wire harness  410 . The conductive pads  410  act like “targets” for connecting components.  FIG. 9  illustrates one exemplary embodiment of an electrical connector  530  that creates an electrical connection between the conductive pad  512  and a headliner component  520 . As shown in  FIG. 9 , a conductive pad  512  is located on the headliner substrate  501 . The electrical connector  530  is designed to pierce the headliner fabric  503 , the headliner substrate  501 , and the conductive pad  512 . The electrical connector  530  includes a hook  531  that prevents the electrical connector  530  from separating from the headliner substrate  501  after installation. As shown in  FIGS. 9 to 11 , a headliner component (not shown) includes one or more connectors (not shown) that pierce the headliner  400  and contact the conductive pads  412 . In various exemplary embodiments, the connectors (not shown) may pierce the headliner core to reach the conductive pads  412 . The electrical connector  530  is a conductor that electrically couples the conductive pad  512  to the headliner component  520 . As outlined above with respect to  FIGS. 2 and 3 , the conductive pad  112  can be provided at one or more locations on the headliner substrate  101 . 
       FIGS. 10 and 11  show a second exemplary embodiment of an electrical connector  630  that provides an electrical connection between the integral wire harness (not shown) and a headliner component  620 . Headliner component  620  includes electrical connectors  630 . The electrical connectors  630  pierce through the headliner  600  to contact the connector pads (not shown). In various exemplary embodiments, the electrical connectors  630  and/or other connectors secure the component  620  to the headliner  600 . 
       FIG. 12  illustrates another embodiment of a connector that provides an electrical connection between a headliner component  120  and the wire harness  710 . In various exemplary embodiments, the wire harness (not shown) is preprinted on a carrier product,  704  such as, for example, thermoplastic film, non-woven scrim, or paper sheet, which is attached to the headliner substrate  701 . The headliner substrate  701  comprises e.g. a thermoplastic material with a thickness of about 3 mm. A connector  730 , which comprises e.g. a copper material or an aluminium material, is placed in the headliner substrate  701 . The connector  730  may be inserted after the headliner  700  is formed or during formation of the headliner substrate  701 , such as, for example, by insert molding. A portion of the connector  730  extends through the headliner fabric  703 . In various exemplary embodiments, the connector  730  is adapted to be coupled to a headliner component  720 . In the embodiment shown in  FIG. 12 , the connector  730  is coupled to the headliner component  720  with a spring detent mechanism  732 , but any known or later-developed attaching device, structure or mechanism may be used instead of or in addition to, the detent spring  732 .  FIG. 13  shows schematically a roof structure according to a further embodiment of the present invention. The headliner  100  comprises a printed connection means  1  and a substrate layer  2 , on which the printed connection means  1  is applied.  FIG. 14  shows schematically a roof structure according to a further embodiment of the present invention. Contact strips  998  of electrically conductive material are embedded in the headliner  100  during manufacturing such that they make contact with the printed circuit  110  and extend into a cutout area  999 . The cutout area  999  is trimmed in such a way that the contact strip  998  is not broken, e.g. by die cutting or “kiss-cutting” to a controlled depth. A release film  997  prevents plastics or adhesive residue from adhering to the contact strip  998 . 
     It should be noted that references to relative positions (e.g., “top” and “bottom”) in this description are merely used to identify various elements as are oriented in the figures. It should be recognized that the orientation of particular components may vary greatly depending on the application in which they are used. 
     It should be understood that the drawings are not necessarily to scale. In certain instances, details that are not necessary to the understanding of the invention or render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein. 
     It should be appreciated that the construction and arrangement of the wire harness, as shown in the various exemplary embodiments, is illustrative only. While the wire harness, according to this invention, has been described in conjunction with the exemplary embodiments outlined above, various alternatives, modifications, variations, improvements, and/or substantial equivalents, whether known or that are or may be presently unforeseen, may become apparent. Accordingly, the exemplary embodiments of the console according to this invention, as set forth above, are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention. Therefore, the description provided above is intended to embrace all known or later-developed alternatives, modifications variations, improvements, and/or substantial equivalents. 
     Various features and advantages of the invention are set forth in the following claims.