Abstract:
This invention is a lumbar support device consisting of a flexmat and a supporting mechanism. The invention is capable of providing an infinite number of vertical adjustment points. The supporting mechanism is connected to the flexmat via slide elements and may travel up and down the side rails of the flexmat assuring infinite adjustment positions for the lumbar support. The movement of the supporting mechanism both vertically along the flexmat and horizontally relative to the seat back is accomplished through the use of wire cables, tractions cables, and a series of pulleys. Use of the pulley system reduces the load of the actuators needed in this device and helps avoid any interference that may occur with other seat components including foam.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims priority to U.S. Provisional App. No. 60/607,668 filed Sep. 7, 2004. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     Not Applicable.  
       APPENDIX  
       [0003]     Not Applicable.  
       BACKGROUND OF THE INVENTION  
       [0004]     1. Field of the Invention  
         [0005]     This invention relates generally to lumbar support devices and, more particularly, to lumbar support devices for use in thin packaging spaces.  
         [0006]     2. Related Art  
         [0007]     Lumbar support devices are well known in the art. Lumbar support is important for achieving an anatomically correct seating posture. If an individual does not receive proper back support, it can lead to lower back pain, increased muscle activation, increased tension on ligaments, and increased pressure on the spine. With the recent trend of car manufacturers reducing the packaging size available for the lumbar support mechanism, seat manufactures have been looking for ways to provide the needed lumbar support with thinner lumbar devices. As such, it is extremely important to develop a lumbar support system that is thin in packaging size but will provide appropriate lumbar support.  
         [0008]     The production of lumbar support through the use of a flexmat in combination with other elements has long been known in the art. However, the flexmat mechanisms used in the prior art only allowed the seat occupant to receive lumbar support at certain heights along the seat. As such, the occupant was not always able to have the greatest lumbar support at the exact height in which he/she desired. Rather, the occupant would have to settle for the location at which the lumbar was provided.  
         [0009]     Accordingly, there remains a need for a lumbar support system that is thin in packaging dimension and can provide an infinite number of heights at which lumbar support may be provided to the seat occupant.  
       SUMMARY OF THE INVENTION  
       [0010]     It is in view of the above problems that the present invention was developed. The invention is a lumbar support device having a flexmat, a cross member, and a pulley system actuated by a series of actuators and cables. In this system, the seat occupant may apply lumbar support in varying degrees at any position vertically along the flexmat because the support mechanism is allowed to slide along the side rails of the flexmat. As such, the occupant may receive lumbar support at the exact location in which it is desired. Furthermore, due to the use of the pulley system within this invention, the moving parts of the system may be actuated within a small dimension thereby assuring a small packaging size. Finally, this lumbar support system is less expensive to manufacture than most lumbar support devices because the pulley system allows the use of smaller, less expensive actuators and allows for an opportunity to use less expensive Kelvar wires instead of the normal steel cables.  
         [0011]     In the present invention, the flexmat is attached to the seat frame. A support mechanism is attached to the side rails of the flexmat via two slide elements. The slide elements allow the support mechanism to move vertically up and down the flexmat. The support mechanism consists of a cross member that is mounted on two sliding brackets which in turn are mounted on the seat frame. The cross member may move in a horizontal direction from a position further away from the flexmat to a position closer to the flexmat, and vice versa. Movement in the direction of the flexmat will force the flexmat to bend, thus providing support to the occupant at that location. An in/out wire moves the cross member in and out relative to the flexmat. The wire is run through a series of pulleys and along the backside of the cross member. When the actuator actuates the in/out cable wire, the cross member is moved forward towards the flexmat. When the actuator moves in the opposite direction, the pressure exerted upon the cross member is reduced such that the pressure exerted by the foam of the seat and/or the weight of the seat occupant will push the cross member in a direction away from the flexmat consequentially reducing the amount of support being applied to the seat occupant. The cross member also is connected to an up/down wire. The up/down wire runs in a diagonal direction across the back of the cross member. When the up/down wire is actuated, the movement of the up/down wire forces the cross member to move up or down the flexmat side rails. The diagonal design ensures that each side of the flexmat moves the same distance and at the same pace.  
         [0012]     The pulley system used in this invention provides many advantages. First, it assists in reducing the load of the actuators used within this lumbar device. As such, smaller, less expensive actuators may be used. Second, it transmits movement from the actuator to the moving parts of the cross member while avoiding interference with the foam of the seat or other seat components. Finally, the pulley system potentially allows for the use of a wire made of Kelvar. The Kelvar wire is cheaper and less resistant to breaking especially when used in conjunction with the plastic pulley wheels. In such cases when Kelvar wire is used, the plastic pulley wheels may even be fixed such that the wire merely slides along the path created by the pulley rather than turning around the moving wheel.  
         [0013]     Further features and advantages of the present invention, as well as the structure and operation of various embodiments of the present invention, are described in detail below with reference to the accompanying drawings.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]     The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and together with the description, serve to explain the principles of the invention.  
         [0015]      FIG. 1  illustrates a front view of the lumbar support device.  
         [0016]      FIG. 2  illustrates a rear view of the lumbar support device.  
         [0017]      FIG. 3  illustrates a front view of the support mechanism in isolation.  
         [0018]      FIG. 4  illustrates a rear perspective view of the support mechanism in isolation.  
         [0019]      FIG. 5  is a front perspective view of the support mechanism in combination with the sliding brackets, the up/down actuator, and the in/out actuator.  
         [0020]      FIG. 6  is another front perspective view of the support mechanism in combination with the sliding brackets and the up/down actuator.  
         [0021]      FIG. 7  illustrates a front perspective view of the lumbar support device. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]     As shown in  FIGS. 1, 2  and  7 , the preferred embodiment of this lumbar support device  8  includes a flexmat  10 . The flexmat  10  consists of a pair of side rails  14  and  15  and a plurality of transverse supporting wires  12  connecting the side rails  14  and  15 . It should be noted that the term flexmat is defined to include any supporting wires that may assume varying geometrical configurations between the side rails  14  and  15 , such that the transverse supporting wires might not be parallel between the side rails  14  and  15 . In addition, the transverse supporting wires  14  and  15  are not required to be coplanar with the side rails  14  and  15 . The flexmat  10  is fixedly attached to the seat frame at various points along the top and bottom of the flexmat  10 . When pressure is applied to the surface of the flexmat, it is capable of bending in a concave position relative to the seat frame, thus producing lumbar support to the seat occupant at the point in which the concave position exists.  
         [0023]     The flexmat  10  is connected to a support mechanism  36  via two slide elements  16 . These slide elements  16  may be designed such that the side rails  14  and  15  of the flexmat  10  are merely placed within a groove of the slide elements  16  or they may take the form of clips so that the slide elements  16  do not lose connection with the side rails  14  and  15  during operation.  
         [0024]     As seen in  FIGS. 3-6 , the slide elements  16  are fixedly attached to the cross member  26 . The body  27  of the cross member  26  runs perpendicular to the side rails  14  and  15  and parallel to the transverse supporting wires  12 . The cross member  26  has two arms  37  and  39  which extend in a perpendicular direction from the body  27  of the cross member  26 . The two arms  37  and  39  are attached to sliding brackets  34  which in turn are fixedly attached to the seat frame  40 . The cross member  26  is free to move along the length of these sliding brackets  34  from a position away from the flexmat  10  to a position closer to the flexmat  10 , and vice versa.  
         [0025]      FIGS. 3-6  also depict the support mechanism of the present invention. The horizontal movement of the support mechanism is accomplished through the use of at least one in/out actuator  42 , an in/out wire  44 , and two separate horizontal pulleys  30  and  32 . The horizontal pulleys  30  and  32  are located in a position within the sliding bracket  34 . The first end of the in/out wire  44  is operatively engaged with the in/out actuator  42  such that the in/out actuator  42  may apply traction to the in/out wire  44 . The second end of the in/out wire  44  is fixedly attached to the seat frame  54 , or any other stationary object in the area such as the sliding bracket  34 . If so desired, instead of attaching the second end of the in/out wire  44  to the seat frame  54  or the sliding bracket  34 , the second end of the in/out out wire  44  may also be attached to the in/out actuator  42 . If this is done, the attachment will occur in a difference area of the actuator than the attachment of the first end.  
         [0026]     The in/out wire  44  travels from the in/out actuator  42  around the first horizontal pulley  30  down through an indentation  46  in the arm  37  of the cross member  26  and around the backside of the body  27  of the cross member  26  relative to the flexmat  10 . The in/out wire  44  continues along the entire length of the back of the cross member  26  where it sits in a grooved portion  50 . The grooved portion  50  of the back of the cross member  26  helps to ensure that the in/out wire  44  stays in place during operation. This grooved portion  50  may also take the form of a clip. The in/out wire  44  runs completely across the rear of the cross member  26 , then travels up through the indentation  46  of the arm  39 , and then around a second horizontal pulley  32  where it is then attached to the seat frame  54 , the sliding bracket  34 , or looped around the back of the cross member  26  and attached to the in/out actuator  42 . On the backside of the cross member  26  where the cross member body  27  meets the arms  37  and  39 , there exists two cable ramps  52 . These cable ramps  52  are generally made of plastic but can be made of any material that reduces the friction between the back side of the cross member  26  and the in/out wire  44 . These cable ramps  52  also lift the in/out wire  44  slightly from the back of the cross member  26  so that the in/out wire  44  will not make contact with the up/down wire  28 .  
         [0027]     As can be deciphered from  FIG. 5 , horizontal movement of the cross member along the sliding brackets  34  occurs when the in/out actuator  42  applies traction to the first end of the in/out wire  44 . The force is transferred along the pulley system such that it causes the cross member  26  to move in a horizontal direction towards the flexmat  10 . The cross member  26  may move a distance equal to the length in which the arms  37  and  39  are allowed to travel in the sliding brackets  34 . When the cross member  26  is moved in a horizontal direction, it exerts pressure upon the flexmat  10  causing an apex to form at that location in the flexmat  10 . Such apex is where the greatest amount of lumbar support will be provided to the seat occupant.  
         [0028]     The support mechanism  36  is also capable of moving up and down the side rails  14  and  15  of the flexmat  10 .  FIG. 6  depicts the support mechanism such that the up/down actuator  56  may be viewed. The up/down wire  28  is attached to a vertical actuator  56 . The type of cable used for the up/down wire  28  is a traction cable, sometimes called a Bowden cable. Generally, a Bowden cable has a sheath with a wire coaxially disposed within the sheath and sliding within it. At one end of the Bowden cable is an actuator. The actuator may be a manual device such as a hand wheel or lever, or it may be a power device such as an electric motor and gear assembly. At the other end of the traction cable, the sleeve is generally fixedly mounted to a bracket or other attachment and the wire, proceeding from the end opening of the sleeve, is attached to a moving component of the lumbar support system.  
         [0029]     In this invention, however, both ends of the Bowden cable are attached to the up/down actuator  56 . In addition, this Bowden cable possesses two different sleeves, an up sleeve  20  and a down sleeve  18 . Both ends of the up sleeve  20  are fixedly attached, one at  62  and the other at  64 . Likewise, both ends of the down cable  18  are fixedly attached, one at  58  and one at  60 .  
         [0030]     One end of the up/down wire  28  travels from its attachment point on the up/down actuator  56  through the up sleeve  20  until it reaches the sleeve attachment point  64  where it then travels under the slide element  16  and around the first vertical pulley  24 . The up/down wire  28  continues over this first vertical pulley  24  in a diagonal direction relative to the cross member  26  and goes through a notch  66  located within the cross member body  27 . It then continues around the second vertical pulley  22 . At this point, the wire  28  extends under the slide element  16  and into the down sleeve  18 . The wire  28  continues through the down sleeve  18  and is attached to another portion of the up/down actuator  56 . The two ends of the up/down wire  28  are attached to the up/down actuator  56  such that movement of the actuator  56  in one direction causes the cross member  26  to move up the flexmat side rails  14  and  15  and movement of the actuator  56  in the opposite direction causes the cross member  26  to move down the side rails  14  and  15  of the flexmat  10 .  
         [0031]      FIGS. 3-5  shows the detail of the notch  66  located within the cross member body  27  and the first and second vertical pulleys,  24  and  22  respectively. The vertical pulleys  24  and  22  are located on opposite ends and opposite sides of the cross member  26  such that when the up/down wire  28  is thread from the first vertical pulley  24  to the second vertical pulley  22 , the wire  28  cuts diagonally across the cross member  26 . A notch  66  exists in the middle of the cross member body  27  such that the up/down wire  28  will not make contact with the grooved portion  50  of the back of the cross member  26  or with the in/out wire  44  running along that grooved portion  50 . The diagonal positioning of the vertical pulleys  24  and  22  transfers the forces over the cross member  26  equally such that each end of the cross member  26  will move the same distance and at the same rate when traction is applied in either direction by the up/down actuator  56 .  
         [0032]     In view of the forgoing it will be seen that the several advantages of the invention are achieved and attained.  
         [0033]     The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated.  
         [0034]     As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or 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.