Abstract:
A four way lumbar support for an automobile seat includes a wire array, a fixed frame, and a basculating arm. When in its extended position, the basculating arm exerts pressure on the wire array thus providing lumbar support to the seat occupant at that point. A system of cables and sliding connections allows the basculating arm to slide along the fixed frame so that the lumbar support may be provided at different heights within the seat.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a divisional of U.S. patent application Ser. No. 11/572,628, filed Jun. 14, 2007, and published as U.S. Patent Application Publication No. 2007/0296256 on Dec. 27, 2007, which is a national stage entry of PCT/US2005/027051, filed Jul. 29, 2005, and published as WO 2006/015247 on Feb. 9, 2006, which claims priority from U.S. Provisional Patent Application No. 60/592,891 filed Jul. 30, 2004, the entire contents of each of the foregoing are hereby incorporated by reference. 
    
    
     BACKGROUND 
     This invention is in the field of lumbar supports for automobile seats. 
     There is a continuing need in the field of lumbar supports for seats in motor vehicles and other transportation vehicles for reducing the size of the package of components necessary to provide lumbar support, both in terms of overall volume and front to back depth of the lumbar support in a retracted position. 
     Car manufacturers have gradually reduced the size of the space allotted for lumbar support mechanisms in their motor vehicle seats. Normally the packaging space for lumbar support systems is around 90 mm. However, seat comfort devices such as heating and cooling mechanisms and massaging mechanisms are becoming more frequent and desirable in motor vehicle seating. As such, the space allotted for lumbar support devices has been decreased to allow for room for these other devices. In addition, manufacturers desire narrower, less bulky seats so as to increase the passenger area available to the occupants of the vehicles. Some manufacturers are requiring that the packaging space for lumbar support systems be as thin as 30 mm. This presents significant difficulties to lumbar support manufacturers as lumber support systems are typically much thicker than 30 mm. 
     In addition, car manufacturers are also looking to provide lumbar support in second and third row seating. These seats often are designed to have a thinner overall construction because of the need to maximize cabin space for the passengers as well as cargo room for storage. As such, there is a continuing need in the art to develop thinner lumbar support mechanisms that provide lumbar support despite the narrowed space restrictions and the other comfort devices located within the seat. 
     SUMMARY 
     It is in light of the above described needs and advantages that the present invention was developed. The present invention is a lumbar support for a seat for an automobile or other transportation vehicle with an extremely thin packaging thickness. The thickness of the various embodiments of this invention ranges from 15 mm-19 mm. 
     In one embodiment of the present invention, the lumbar support is a flexmat consisting of wires running transversely across guide rails. The flexmat is mounted in a fixed position within the seat back frame. A basculating arm runs horizontally across the flexmat and is mounted to a fixed frame within the lumbar support system so that when the basculating arm is moved from its retracted position to its extended position, it applies pressure on the flexmat and thus provides increased support at that position to the seat occupant. The basculating arm is also mounted to the fixed frame in such a manner that allows it to move vertically along the fixed frame to provide lumbar support to the seat occupant at varying heights. 
     This vertical movement is achieved through the use of a traction cable, sometimes called a Bowden cable. The 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 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. The actuator moves the wire relative to the sleeve by pulling the wire out from the sleeve. In this invention, the actuator places traction on the traction cable thus causing the basculating arm to move vertically along the fixed frame. In one embodiment of this invention, the Bowden cable is not used to move the basculating arm in a vertical direction. Rather, this task is accomplished through the use of nuts and screws. A motor is attached to a rod such that the motor rotates the rod which in turn drives the screws in a certain direction. The basculating arm is connected to the screws via a multitude of nuts. When the screws are turned in one direction, the nuts are driven vertically up or down the screws thus causing the basculating arm to move vertically along the flexmat. 
     In another embodiment of this invention, the basculating arm is not used as the mechanism for creating the lumbar support. Rather, movement of the lumbar support from a retracted position to an extended position through a selectable range of intermediate positions is achieved with a Bowden cable. The Bowden cable is attached to one end of the wire array such that when the actuator puts fraction on the fraction cable, the wire array bends creating an arch in the wire array and thus providing support to the seat occupant at that point. Movement of this lumbar support system vertically along the seat frame is achieved with a separate Bowden cable. Contrary to the previous embodiments, the wire array in this embodiment, rather than the basculating arm, moves vertically along the fixed frame. 
     In another embodiment, a lumbar support for a transportation vehicle includes a flexmat, a basculating arm, and a double pulley. The flexmat is adapted to mount on a seat backrest frame and is extendable from a first position to a second position. The basculating arm is configured for movement along the flexmat to provide support at a plurality of heights along the flexmat. The double pulley is attached to the basculating arm such that movement of the double pulley mediates movement of the basculating arm between a retracted and an extended position. The basculating arm moves the flexmat from the first position to the second position as the basculating arm moves from the retracted to the extended position. 
     In another embodiment, a lumbar support for a transportation vehicle includes a flexmat, a basculating arm, an actuator, and a double pulley. The flexmat is adapted to mount on a seat backrest frame such that the flexmat may extend from a first position to a second position. The basculating arm is positionable along the flexmat, and the actuator is operable to raise and lower the basculating arm. The double pulley is attached to the basculating arm such that movement of the double pulley mediates movement of the basculating arm between a retracted and an extended position. When the basculating arm moves from the retracted to the extended position, it moves the flexmat from the first position to the second position. 
     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 
       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. In the drawings: 
         FIG. 1  is a perspective view of the lumbar support of the present invention. 
         FIG. 2  is another perspective view of the lumbar support of the present invention. 
         FIG. 3  is a front perspective view of another alternative embodiment of the present invention. 
         FIG. 4  is a front perspective view of a third embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the drawings in which like reference numbers indicate like elements,  FIGS. 1 and 2  depict a first embodiment of the lumbar support assembly of the present invention. The assembly is comprised generally of a flexmat  10 , a fixed frame  20 , an up/down actuator  30 , an in/out actuator  40 , a basculating arm  50 , and a double pulley  60 . 
     The flexmat assembly  10  is an assembly of components including guide rails  12 , mounting hooks  14 , and a wire array  16 . Mounting hooks  14 , which may be a bent portion of the guide rails  12 , or which may be additional wires assembled with guide rails  12 , are used to hook the lumbar support assembly into a mount on the seat frame. Mounting hooks  14  are adaptable to various seat frames. The wire array  16  in the depicted embodiment is composed of horizontal wires assembled between guide rails  12 . The wire array  16  also has stabilizing vertical connection members  18 . 
     The flexmat assembly  10  is attached to a fixed frame  20  such that the upper portion of the flexmat  20  is held in a relatively stable position while the lower portion is allowed to move in a direction away from the fixed frame  20  when pressure is applied by the basculating arm  50 . The basculating arm  50  is slideably connected to the fixed frame  20  so that the basculating arm  50  may move substantially vertically along the fixed frame  20  in order to provide support at differing heights along the flexmat  10 . Also connected to the basculating arm  50  is a raise rod  22  and a lowering rod  24 . 
     The up/down actuator  30  powers the vertical movement of the basculating arm  50  along the fixed frame  20 . The up/down actuator  30  is disposed to apply traction to a Bowden cable wire in order to slide it axially through the Bowden cable sleeve. In the depicted embodiment, the up/down actuator  30  is comprised of an electric motor and a gear housing containing the requisite components for applying the traction. Any of a variety of known power actuator gearing systems may be assembled with the lumbar support of the present invention without departing from the scope of the present invention. 
     The up/down actuator  30  is connected to the raise rod  22  by the up-cable  26 . The up-cable  26  is a Bowden cable comprised of a cable sleeve with a wire disposed to slide through the sleeve. The raise rod  22  provides the connection point at which the wire end of the up-cable  26  is attached so that the basculating arm may be moved in an upward direction once traction is applied by the up/down actuator  30 . The up/down actuator  30  is also connected to the lowering rod  24  by the down-cable  28 . The down-cable  28  is also a Bowden cable comprised of a cable sleeve with a wire disposed to slide through the sleeve. The lowering rod  24  provides the connection point at which the down-cable wire end is attached so that the basculating arm  50  may be moved in a downward direction once traction is applied in the opposite direction by the up/down actuator  30 . 
     In this embodiment, the lumbar support is provided to the seat occupant through the pressure exerted on the flexmat  10  by the basculating arm  50 . The basculating arm  50  is connected to a double pulley  60 . The double pulley  60  is generally wedge shaped with a rounded edge. The rounded edge contains a groove  62 . Two Bowden cables, the in-cable  32  and the out-cable  34 , are attached to this double pulley  60 . The wire end of the in-cable  32  is attached to one end of the rounded edge of the pulley while the wire end of the out-cable is attached to the opposite end of the rounded edge. The wires of each of these cables  32  and  34  travel along groove  62 . When traction is applied by in/out actuator  40  in one direction, in-cable  32  pulls pulley  60  in a downward direction causing the basculating arm  50  to move in a direction away from flexmat  10 . When traction is applied by actuator  40  in an opposite direction, the out-cable  34  pulls pulley  60  in an upward direction causing the basculating arm  50  to move in a direction towards flexmat  10 . Once the basculating arm  50  makes contact with the flexmat  10 , any further movement towards flexmat  10  causes flexmat  10  to shift away from fixed frame  20  and thus push against the seat occupant providing the desired lumbar support at the height at which basculating arm  50  is located. 
       FIG. 3  depicts an alternative embodiment of the present invention. The mechanical aspects of the lumbar support remain substantially equivalent to the previously depicted embodiment. The lumbar support is provided through the same basculating arm  50  type mechanism of arm  50 . Furthermore, double pulley  60  and in/out actuator  40  are also substantially equivalent to the previously described embodiment. In the embodiment depicted in  FIG. 3 , however, basculating arm  50  does not slide along a fixed frame. Rather, basculating arm  50  moves up and down two screws  70  located in fixed positions alongside flexmat  10 . A motor  80  and drive rod  82  connect the two screws  70  via two separate gear housings  84 . Located on each screw  70  is at least one nut  72 . The nuts and screws are threaded in such a manner that when the screws  70  are turned in one direction, the nuts  72  move along the screws at the same rate and in the same direction. At the end of each screw  70  is a pillow block  74 . The pillow block  74  limits the distance the nut  72  may travel and prevents the nut  72  from moving off the screw  70 . The basculating arm  50  is attached to each nut  72  such that the basculating arm  50  moves in the same direction and distance as the nuts  72  themselves. 
     The final embodiment as shown in  FIG. 4  does not use a basculating arm  50  to create the lumbar support. Rather, the lumbar support assembly contains an arching pressure surface  90 . The arching pressure surface  90  consists of a wire array  92 , guide rails  94  and  95 , an upper horizontal mounting rod  98 , a lower horizontal mounting rod  96 , and an elevation rod  124 . The wire array  92  used in this embodiment is substantially similar to that of the other embodiments except that this wire array includes a slide piece  99 . The slide piece  99  is generally a solid piece of plastic or metal that is attached to the horizontal mounting rod  96  and forces the wire array  92  to form an arch when compressed. The slide piece  99 , however, is not limited to this description and may take any shape, including being grooved, ribbed or hollow, and may be made of any material as long as it causes the wire array to arch when compressed. 
     The wire array  92  is mounted on guide rails  94  and  95  such that it may move relative to them for creating an arch which will support a seat occupant&#39;s lumbar spine. This relative motion may be achieved in a variety of ways, all within the scope of the present invention. In the depicted embodiment, the wire array  92  is mounted with a snap fit  91  at the lower horizontal mounting rod  96  and the upper horizontal mounting rod  98  such that it may pivot there. The upper horizontal mounting rod  98  is connected to the guide rails  94  and  95  with slide mounts  93  such that the upper horizontal mounting rod  98  may slide up and down the guide rails  94  and  95 . The combination of pivoting motion around pivoting mounts  91  and sliding motion of slide mounts  93  along guide rails  94  and  95  allows the wire array  92  to be flexed into an arch as its upper end slides on the plane defined by the guide rails  94  and  95 . 
     The in/out actuator  97  is connected to the wire array  92  by a Bowden traction cable  100 . Bowden cable  100  is comprised of a cable sleeve  102  with a wire  104  disposed to slide through the sleeve  102 . The in/out actuator  97 , is disposed to apply traction to the Bowden cable wire  104  in order to slide it axially through the Bowden cable sleeve  102 . In the depicted embodiment, the in/out actuator  97  is comprised of an electric motor  106  and a gear housing  108  containing the requisite components for applying the traction. Any of a variety of known power actuator gearing systems may be assembled with the lumbar support of the present invention without departing from the scope of the present invention. 
     The Bowden cable sleeve  102  is mounted at the lower horizontal mounting rod  96 . This mount  110  is on the opposite end from the mount of the Bowden cable wire end  112 , which is attached to the slide  99 . Dynamic tension exerted by the traction applied by the actuator  97  pulls sleeve mount  110  and wire mount  112  towards one another, providing the pressure and traction necessary to force the wire array  92  into an arched position and further necessary for maintaining that position for support of the seat occupant&#39;s weight. 
     The arching pressure surface  90  is slideably connected to a fixed frame  114  and therefore can move vertically along the fixed frame  114 . This vertical movement allows the seat occupant to adjust the height at which the lumbar support is provided. The up/down actuator  116  that provides the tension for this movement is connected to a down cable  118  and an up cable  120 . The Bowden cable sleeve  121  of the up cable  120  is mounted to the top portion  122  of the fixed frame  114  and the wire end mount  123  is located on the elevation rod  124 . Dynamic tension exerted by the up/down actuator  116  pulls the sleeve mount  122  and wire mount  123  towards one another thus moving the wire array  92  substantially vertically up the fixed frame  114 . The Bowden cable sleeve  125  of the down cable  118  is mounted on the bottom portion  126  of the fixed frame  114  and the wire mount  127  is located on the lower horizontal mounting rod  96 . Dynamic tension exerted by the up/down actuator  116  pulls the sleeve mount  126  and the wire mount  127  towards one another thus moving the wire array  92  vertically down the fixed frame  114  resulting in arching of surface  90 . 
     In view of the forgoing it will be seen that the several advantages of the invention are achieved and attained. 
     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. 
     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.