Patent Abstract:
The invention relates to a thin profile adjustable lumbar support system, particularly for use in automotive seat backs and other equipment used for sitting and reclining. The lumbar support system is assembled utilizing injection molding and overmolding technology to form some components and connect other components.

Full Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to the field of lumbar support systems, especially as such systems are used in automotive seats and chair back rests. 
     2. Related Art 
     Lumbar support systems have become a popular feature for use in automotive seats, office chairs, beds, lounge chairs and various other furniture and equipment used for sitting or reclining. Numerous and varied designs of lumbar support systems have been developed and produced. 
     The manufacture of many lumbar support systems requires that a number of distinct components be hand assembled or assembled by automatic equipment. This assembly process is a component of the cost and time required to manufacture such systems. 
     SUMMARY OF THE INVENTION 
     In an embodiment of the present invention, a portion of a lumbar support system is formed when material is injection molded to form a connector portion that connects a hanger wire and a terminal end portion of a bowden cable assembly conduit. 
     It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG. 1  illustrates a plan view of an overmolded lumbar support system. 
         FIG. 2  illustrates a plan view of the injection molded connection of a bowden cable and a hanger wire. 
         FIG. 3  illustrates a perspective view of an overmolded lumbar support system as attached to a seat. 
         FIG. 4  illustrates a perspective view of an overmolded lumbar support system attached to a seat with an intermediate material between the seat back and the flexible lumbar strap. 
         FIG. 5  illustrates several views of one embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or its uses. 
       FIGS. 1 and 2  depict a thin profile, flexible lumbar support system comprising a first hanger wire  24 , a second hanger wire  22 , a bowden cable assembly  40 , an injection molded flexible lumbar strap  10  and a injection molded connector portion  30 . The bowden cable assembly  40  consists of a section  42  of a conduit, through which a wire  44  runs, and the wire  44  terminates in a bullet connector  46 . 
     According to an embodiment of the present invention the lumbar support system is manufactured by arranging the first hanger wire  24 , second hanger wire  22 , and bowden cable assembly  40  in a mold cavity of an injection molding apparatus. The injection molding apparatus injects a plastic into the mold cavity which forms the flexible lumbar strap  10  and the injection molded connector portion  30 . The injection molded flexible lumbar strap  10  and injection molded connector portion  30  connect the first hanger wire  24 , second hanger wire  22  and bowden cable assembly  40 , as shown in  FIGS. 1-2  and described in greater detail below. 
     On one side of the flexible lumbar strap  10 , a portion of the second hanger wire  22  is overmolded to form the flexible lumbar strap  10 , such that the second hanger wire  22  is integrally connected to the flexible lumbar strap  10  in a hinge-like manner. That is to say, the second hanger wire  22  is connected to the flexible lumbar strap  10  in such a way that rotation of the hanger wire, with respect to the flexible lumbar strap, about the axis of the overmolded portion is possible, but rotation about any other axis and translation of the second hanger wire  22  with respect to the flexible lumbar strap  10  is restricted. 
     The overmolding of the second hanger wire  22  preferably occurs during the same process in which the flexible lumbar strap  10  is formed, and the material that connects the flexible lumbar strap  10  to the second hanger wire  22  is preferably the same as the material that forms the body of the flexible lumbar strap  10 . Thus, a continuous connection is formed between the flexible lumbar strap  10  and the second hanger wire  22 . 
     The body of the flexible lumbar strap  10  may consist of any design that is conducive to a desirable response to applied tensile forces. In the embodiment of the present invention depicted in  FIGS. 1-2 , the flexible lumbar strap  10  has three elongated openings  16 . The number and size of the openings  16  as well as the material used and the thickness of the flexible lumbar strap  10  may be modified to achieve desired design parameters, such as a target elasticity and yield strength, for a corresponding design width of the flexible lumbar strap  10 . 
     On the side of the flexible lumbar strap  10  opposite the connection to the first hanger wire  24 , the bullet connector  46  of the bowden cable assembly  40  is overmolded. The bullet connector  46  is preferably overmolded during the same process in which the flexible lumbar strap  10  is formed and the second wire hanger  22  is overmolded, and preferably the same material is used to overmold the bullet connector  46  that was used to form the flexible lumbar strap  10 , such that the bullet connector  46  is integrally connected to the flexible lumbar strap  10 . While a bullet connector  46  is used in this embodiment of the invention, numerous types of connectors, such as an eye hook, could be used in place of a bullet. 
     The injection molded connector portion  30  is formed apart from the flexible lumbar strap  10  and is connected to the flexible lumbar strap  10  only by the wire  44 . In the formation of the injection molded connector portion  30 , portions of both the second wire hanger  24  and the bowden cable assembly  40  are overmolded, preferably as described below. 
     A portion of the first wire hanger  24  is overmolded such that it is integrally connected to the injection molded connector portion  30  in a hinge-like manner. That is to say the connection of the first wire hanger  24  to the injection molded connector portion  30  is such that rotation, with respect to the injection molded connector portion  30 , of the first wire hanger  24  is possible about the axis of the overmolded portion of the first wire hanger  24 . However, once the injection molded connector portion  30  is formed, and with respect thereto, the first wire hanger  24  is restricted from translation and rotation about any other axis. 
     During the formation of the injection molded connector portion  30 , a section  42  of a conduit of the bowden cable assembly  40  is also overmolded, as best seen in  FIG. 2 . The overmolded portion of the section  42  of a conduit is held in place by the injection molded material and is, therefore, secure in relation to the injection molded connector portion  30 . Preferably the overmolded portion of the section  42  of a conduit is approximate to the terminal  48  of the section  42  of a conduit and extends slightly beyond the injection molded connector portion  30 . 
     As shown in  FIGS. 3 and 4 , when attached to a seat for use, the first hanger wire  24  and second hanger wire  22  are attached to first and second support structures  54 ,  52 , such as opposing columns of a seat frame, such that the flexible lumbar strap  10  extends across the back of the seat  50 . The first and second hangers  24 ,  22  are attached to the support structures  54 ,  52  in a rotatable manner allowing the lumbar strap  10  to be pressed forward into the seat back  50  or relaxed backwards away from the seat back  50 . As best seen in  FIG. 1 , a material, preferably plastic, may be overmolded onto the end portions  26  of the first and second wire hangers  24 ,  22  to provide a more desirable interface where the end portions  26  connect to the frame. 
     In an alternate embodiment, shown in  FIG. 4 , an intermediate material  60  may be disposed between the flexible lumbar strap  10  and the back of the seat  50 , so as to either provide a greater range of lumbar support movement or provide lumbar support that is more comfortable for an end user. 
     The embodiment of the invention shown in  FIG. 5  comprises a flexible lumbar strap  10 , a bowden cable assembly  40 , a first and second wire hanger  24 ,  22 , and a secondary conduit  43 . According to this embodiment, the first wire hanger  24  and the terminal portion of the section  42  of a conduit of the bowden cable assembly  40  are overmolded and integrally connected to a first side of the flexible lumbar strap  10 . The wire  44  of the bowden cable assembly  40  passes through the secondary conduit  43 , which is overmolded and integrally attached to a central portion of the flexible lumbar strap  10 . The second wire hanger  22  and the bullet connector  46  at the terminal end of the wire  44  are overmolded to a second side of the flexible lumbar strap  10 . The flexible lumbar strap  10  is preferably formed and/or situated such that it is arched when little or no tension is applied to the wire  44 . Accordingly, when tension is applied to the wire  44  the arch in the flexible lumbar strap  10  is reduced, thereby applying pressure to the seat back  50  and, in turn, to the lumbar region of an end user. 
     As shown in  FIG. 1  the end of the bowden cable assembly  40  that is not attached to the flexible lumbar strap  10  and injection molded connector portion  30  is operatively attached to an actuator  70 . The actuator  70  may vary in complexity and performance from a very simple and inexpensive mechanical device, to a more expensive and complex electrically driven device. Regardless of the complexity of the actuator  70 , its purpose is to create and relieve, as directed by the end user, a tensile force in the wire  44 . This tensile force is transmitted by the wire  44  to the flexible lumbar strap  10 , which, in turn, exerts a force against the back of the seat  50 , either directly or by way of an intermediate material  60 . The force exerted against the back of the seat  50  by the lumbar strap  10  causes the lumbar region of the back of the seat  50  to press outwardly, thereby providing support to the lumbar region of an end user. Conversely, when the force applied to the flexible lumbar strap  10  is reduced, the force applied to the back of the seat  50  is reduced, allowing the back of the seat to recede. Thus, an end user is provided ultimate control over the extent of the lumbar support provided by the seat. 
     As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the invention, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.

Technology Classification (CPC): 1