Patent Publication Number: US-9840171-B2

Title: Adjustable firmness vehicle seat

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This patent application is a continuation of U.S. Pat. No. 9,211,824, which was issued on Dec. 15, 2015, entitled “ADJUSTABLE FIRMNESS VEHICLE SEAT.” The aforementioned related application is hereby incorporated by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention generally relates to a vehicle seat, and more particularly to a vehicle seat having inflatable air bladders for adjusting the firmness of a seat cushion. 
     BACKGROUND OF THE INVENTION 
     Modern vehicles are often equipped with adjustable support in both the seat and seat back. In a vehicle coordinate system, there is defined a hip pivot point, commonly referred to in the automotive industry as the “h-point.” The h-point is defined by the hip joint, which is the pivot point between the torso and the upper leg portions of the body. In vehicle design, the h-point is the point which determines the position of the vehicle occupant in the vehicle coordinate system when he or she is seated on the vehicle seat. The h-point and any seat adjustment apparatus must be taken into consideration when designing the vehicle seat, as well as many other interior components. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present disclosure, a vehicle seat is disclosed. The vehicle seat includes a cushion disposed within a seating member having at least one inflatable first bladder for selectively adjusting a firmness of the cushion. An inflatable second bladder is separated from a support surface of the seating member by the first bladder and is fluidly connected to the first bladder. A vehicle seat hip pivot point is maintained when adjusting the firmness of the cushion by increasing the pressure in the second bladder when the pressure in the first bladder is selectively decreased, and by decreasing the pressure in the second bladder when a pressure in the first bladder is selectively increased. 
     According to another aspect of the present disclosure, a vehicle seat is disclosed. The vehicle seat includes a cushion coupled to a seating member having an inflatable first air bladder. An inflatable second air bladder is positioned adjacent the first air bladder. A hose and control valve is coupled to the first and second air bladders and is configured to maintain a vehicle seat hip pivot point by counteracting a change in air pressure within the first air bladder with an inverse change in pressure within the second air bladder. 
     According to yet another aspect of the present disclosure, a seat assembly is disclosed. The seat assembly includes a seating member having a cushion disposed therein. The cushion includes an inflatable first air bladder for selectively adjusting a firmness of the cushion. An adjustment mechanism is coupled to the air bladder. The adjustment mechanism adjusts a distance between the air bladder and a support surface of the seating member as an air pressure of the air bladder is adjusted to maintain a constant hip pivot point. 
     These and other aspects, objects, and features of the present invention will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a top perspective view of a vehicle seat disposed inside a vehicle; 
         FIG. 2  is schematic side view of a vehicle occupant, illustrating the hip pivot point of the occupant when seated in the vehicle; 
         FIG. 3  is a top perspective view of the vehicle seat, according to one embodiment of the invention; 
         FIG. 4  is a side elevational view of the vehicle seat of  FIG. 3  with portions of the seat cut-away to illustrate the components within the vehicle seat; 
         FIG. 5  is a schematic, front cross-sectional view taken along line V-V of the vehicle seat of  FIG. 3 , illustrating an occupant&#39;s legs seated on a firm seating surface; 
         FIG. 6  is a schematic, front cross-sectional view taken along line VI-VI of the vehicle seat of  FIG. 3 , illustrating an occupants legs seated on a soft seating surface; 
         FIG. 7  is a side elevational view of a vehicle seat, according to another embodiment of the invention, with portions of the seat cut-away to illustrate the components within the vehicle seat 
         FIG. 8  is a schematic, cross-sectional view taken along line VIII-VIII of the vehicle seat of  FIG. 3 , illustrating an occupant&#39;s thighs seated on a firm seating surface; 
         FIG. 9  is a schematic, cross-sectional side view taken along line IX-IX of the vehicle seat of  FIG. 3 , illustrating an occupant&#39;s thighs seated on a soft seating surface; 
         FIG. 10  is a top perspective view of a lower seat frame of the vehicle seat of  FIG. 7 , illustrating one embodiment of a height adjustment mechanism; 
         FIG. 11  is a top perspective view of the lower seat frame and height adjustment mechanism of  FIG. 10 , including an adjustable bladder; 
         FIG. 12  is a bottom perspective view of an upper seat frame of the vehicle seat of  FIG. 7 , illustrating one embodiment of a back support assembly and adjustable bladder; and 
         FIG. 13  is a bottom perspective view of an upper seat frame of the vehicle seat of  FIG. 7 , illustrating another embodiment of a back support assembly and adjustable bladder. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” “interior,” “exterior,” and derivatives thereof shall relate to the invention as oriented in  FIG. 1 . However, it is to be understood that the invention may assume various alternative orientations, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawing, and described in the following specification are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. 
     Referring to  FIGS. 1-4 , reference numeral  10  generally designates a seat assembly for an automotive vehicle  11 . The vehicle seat  10  includes a cushion  12  coupled to a seating member  14 , and the cushion  12  has an inflatable first bladder  16  for selectively adjusting the firmness of the cushion  12 . The vehicle seat  10  includes an inflatable second bladder  18 , which is positioned adjacent the first bladder  16 . A vehicle seat hip pivot point HP, commonly referred to in the automotive industry as an “h-point”, is maintained by counteracting a change in pressure within the first bladder  16  with an inverse change in pressure within the second bladder  18 . 
     As shown in  FIG. 1 , the vehicle seat  10  is generally configured for use in a variety of vehicles  11  in either a front driver seat, a front passenger seat, or a rear seat of the vehicle  11  and generally includes seating member  14 , illustrated in the form of a seat  20  and a seat back  22 , each of which have a cushion  12   a ,  12   b , respectively. A headrest  24  is also mounted to the top of the seat back  22 . The vehicle seat  10  also includes a seat frame formed by lower seat frame  26  ( FIG. 10 ) and upper seat frame  28  ( FIG. 12 ) and may be configured to be mounted on a support surface, such as a floor pan of the vehicle  11 . A track assembly may be coupled to the seat  20  to facilitate fore and aft positioning of the vehicle seat  10 . The vehicle seat  10  is generally designed for the comfort of an occupant, as well as to accommodate and protect the occupant during a collision event. 
     Referring now to  FIG. 2 , the vehicle hip pivot point, referred to as h-point HP, is the location of the occupant&#39;s hip, when seated in the vehicle seat  10 , relative to the floor pan of the vehicle  11  (or to the height above the pavement level). The h-point HP as generally defined by the Society of Automotive Engineers (SAE) is a mechanically hinged hip point of a three-dimensional manikin (SAE J2826 manikin), which simulates the actual pivot center of a human hip. The h-point HP can be thought of, roughly, as the hip joint of a 50 th  percentile male occupant, viewed laterally. Additionally, the h-point HP location is unique to each vehicle  11  and many design criteria related to various vehicle aspects such as safety, interior packaging, visibility, and seating are based off of the h-point HP location. 
     Referring now to  FIGS. 3-4 , the seat  20  is configured to support the occupant&#39;s buttocks and upper thighs upon the seat cushion  12   a , the firmness of which is configured to be selectively adjustable. The cushion  12   a  includes, in part, the first and second bladders  16 ,  18 , and a trim cover  30 . The trim cover  30  is coupled to the seat  20  and/or the lower seat frame  26  ( FIG. 10 ) and covers the cushion  12   a  in an aesthetically pleasing manner. The first and second bladders  16 ,  18  are enclosed within the trim cover  30  and are arranged in a substantially stacked relationship where the first bladder  16  is positioned above the second bladder  18  and below the trim cover  30 , with respect to the floor pan of the vehicle  11 . Optionally, a thin layer of foam  96  may be included between the first bladder  16  and the trim cover  30  and/or the trim cover  30  may be foam backed. Additionally, a thin layer of foam or other material may be included between the first and second bladders  16 ,  18 . In one embodiment, the first and second bladders  16 ,  18  are made of a deformable elastomeric material, such as thermoplastic polyurethane, but can also be made from other suitable deformable material as commonly known in the art. The trim cover  30  may be made of any suitable material commonly known in the art, for example, cloth, leather, or polymers. Additionally, the first and second bladders  16 ,  18  may be substantially similar in terms of functionality; however the geometric shape of the two bladders  16 ,  18  need not necessarily be the same. Stated differently, the first and second bladders  16 ,  18  may be similar in material and the ability to inflate/deflate, but are not necessarily equivalent in size and shape. 
     The first and second bladders  16 ,  18  are provided with inlets  32 , which are fluidly coupled to lines or hoses  34  and a pump  36  for inflating and deflating the bladders  16 ,  18 . Additionally, both the first and second bladders  16 ,  18  may be operably coupled to a pump controller, multiple control valves, and a switch  38  for selectively activating the pump  36 . The switch  38  may be a multi-position switch and can be mounted in a convenient and reachable location, such as a seat side shield or an instrument panel, so the occupant can control the inflation and deflation of the bladders  16 ,  18 . Additionally, the switch  38  may be capacitive and included in the vehicle software, and may be accessible through a touch screen included in the instrument panel or other location. The pump  36  is a conventional pump and pumps either ambient air or a fluid through the valves to the bladders  16 ,  18 . When activated, the pump  36  inflates the bladders  16 ,  18 . Although not shown, the bladders  16 ,  18  may also include exhaust ports, which, when activated by the switch  38 , are opened to deflate the bladders  16 ,  18 . Further, it is within the scope of the present disclosure to use any suitable inflation system to inflate and deflate the bladders  16 ,  18 . It should be noted that the terms “inflation” and “deflation” are used interchangeably herein with the phrases “increase in pressure” and “decrease in pressure.” 
     The firmness of the cushion  12   a  and therefore the seat  20  itself, can be adjusted by increasing or decreasing the pressure within the first bladder  16 . In one embodiment, the bladders  16 ,  18  are air bladders and the inflation system uses air to inflate/deflate the bladders  16 ,  18 . As is easily understood, increasing the air pressure within the first bladder  16  increases the firmness of the cushion  12   a , and decreasing the air pressure within the first bladder  16  decreases the firmness of the cushion  12   a . As the first bladder  16  is inflated, it expands upward, thereby raising, in terms of height relative to the vehicle floor pan, a seating surface  40  of the cushion  12   a . The increased firmness and subsequent rise of the seating surface  40  moves the location of the h-point HP. The opposite is true for decreasing the firmness of the cushion  12   a.    
     According to one embodiment, the second bladder  18  can be utilized to counteract a change in the height of the seating surface  40  caused by an increase or decrease in the pressure within the first bladder  16 . The first and second bladders  16 ,  18  are stacked, therefore a change in pressure within either or both of the bladders  16 ,  18  may raise or lower the seating surface  40 . Additionally, the pump controller can be programmed to automatically adjust the pressure within the second bladder  18  a predetermined and proportionate amount in response to the change in pressure within the first bladder  16 . 
     In operation, and as illustrated in  FIGS. 5-6 , an occupant may selectively change the firmness of the vehicle seat  10 . As shown in  FIG. 6 , when the occupant of the seat  10  wishes to decrease the support provided by the seat cushion  12   a , the occupant can move the switch  38  ( FIG. 3 ) to selectively deflate the upper first bladder  16 , allowing the occupant&#39;s body to sink into the cushion  12   a  to a greater degree. This effectively softens the cushion  12   a  by softening the first bladder  16  and more evenly distributing the occupant&#39;s body load on the cushion  12   a . Deflating the first bladder  16  decreases the height of the first bladder  16 , and therefore lowers the seating surface  40  and the location of the h-point HP. However, the decrease in height of the first bladder  16  can be compensated for by increasing the height of the lower second bladder  18  by automatically inflating the second bladder  18 . Stated differently, an increase in the height of the second bladder  18  compensates for the decrease in height of the first bladder  16 . This enables the occupant to select a softer seat cushion  12   a , yet maintain the overall height of the seating surface  40  and relative location of the h-point HP. As is easily understood, the opposite is true with respect to increasing the firmness of the cushion  12   a . Referring to  FIG. 5 , when increasing the firmness of the cushion  12   a , the first bladder  16  is selectively inflated, and the second bladder  18  is automatically deflated. 
     Additionally, the seat back  22  is configured to support the occupant&#39;s back upon the seat back cushion  12   b , the firmness of which is configured to be selectively adjustable. Referring back to  FIG. 4 , the seat back cushion  12   b  may also have similar first and second bladders  50 ,  52  covered by the trim cover  30 . The first and second bladders  50 ,  52  are disposed within the trim cover  30  and are arranged in a substantially vertical fore/aft relationship where the second bladder  52  is positioned rearward of the first bladder  50 . When the first bladder  50  is inflated, it expands forward, moving a support surface  54  of the cushion  12   b  forward. This does not affect the height of the seating surface  40  of the seat  20 , but it does move the location of the h-point HP. The opposite is true for decreasing the firmness of the cushion  12   b.    
     The second bladder  52  can be utilized to counteract a change in the position of seat back cushion  12   b  caused by an increase or decrease in the pressure within the first bladder  50 . For example, to obtain a softer seat back cushion  12   b , the occupant can selectively deflate the first bladder  50 , allowing the occupant&#39;s back to sink into the cushion  12   b  to a greater degree. Deflating the first bladder  50  decreases the thickness of the first bladder  50 , and therefore also moves the location of the h-point HP rearward in the vehicle  11 . The decrease in the thickness of the first bladder  50  can be compensated for by increasing the thickness of the second bladder  52  by automatically inflating the second bladder  52 . The increase in the thickness of the second bladder  52  compensates for the decrease in thickness of the first bladder  50 . This enables the occupant to select a softer seat back cushion  12   b , yet maintain the location of the h-point HP. As is easily understood, the opposite is true with respect to increasing the firmness of the cushion  12   b . When increasing the firmness of the cushion  12   b , the first bladder  50  is selectively inflated, and the second bladder  52  is automatically deflated. 
     In another embodiment, the above described bladders  16 ,  18 ,  50 ,  52  are liquid bladders and the inflation system uses liquid to inflate/deflate the bladders  16 ,  18 ,  50 ,  52 . Additionally, the bladders  16 ,  18 ,  50 ,  52  may each be made up of a plurality of bladders. It is contemplated that the plurality of bladders that make up each of the bladders  16 ,  18 ,  50 ,  52  can be fluidly communicative via additional lines or hoses. Further, the bladders  16 ,  18  and bladders  50 ,  52  can be fluidly connected to one another by hoses  34 . Control valves can be utilized to allow the air or fluid to flow freely through all the connected bladders  16 ,  18 ,  50 ,  52  when an occupant is seated in the vehicle seat  10 , allowing the bladders  16 ,  18 ,  50 ,  52  to equalize in pressure and firmness. The pump controller may then automatically adjust the h-point HP based on the occupant&#39;s weight and a predetermined and pre-programmed baseline firmness. After this initial equalization, the occupant may selectively adjust the firmness of the cushions  12   a ,  12   b , and the pump controller will inflate or deflate the bladders  16 ,  18 ,  50 ,  52  accordingly. It is also contemplated that a pressure sensor or one of the bladders  16 ,  18 ,  50 , and  52  may be used to sense the presence of a seated occupant, as is generally understood by one having skill in the art. 
     In yet another embodiment, the second bladder  18  is replaced with a height adjustment mechanism that is adapted to adjust the height, relative to the floor pan of the vehicle  11 , of the first bladder  16 . Referring to the illustrated example in  FIGS. 7-11 , the height adjustment mechanism is in the form of at least one variable tension spring  56  mounted to the lower seat frame  26  and positioned below the first bladder  16 . The height adjustment mechanism also includes a motor  58 , a gear  60 , and a spring attachment member  62 . A fixedly mounted connecting rod  64  extends between lateral sides of the seat  20  and a sleeve  65  rotatably encircles the connecting rod  64 . The motor  58  and gear  60  are operably coupled to the sleeve  65  and the spring attachment member  62  is rigidly mounted on the sleeve  65 . The variable tension springs  56  are mounted in tension between the spring attachment member  62  and a forward portion of the lower seat frame  26 . When activated, the motor  58  and gear  60  are adapted to rotate the sleeve  65  and spring attachment member  62 . In the illustrated example, rotating the sleeve  65  and spring attachment member  62  rearward raises a rear portion of the variable tension springs  56  and increases the tension applied thereto. Raising the rear portion of the variable tension springs  56  raises the height of the seating surface  40 . Additionally, as is understood by one of ordinary skill in the art, increasing the tension on the variable tension springs  56  decreases the flex or extension thereof, which means the springs  56  and adjacent first bladder  16  will move downward a smaller distance when placed under load, such as when an occupant sits on the seat  20 . Conversely, rotating the sleeve  65  and spring attachment member  62  forward lowers the rear portion of the variable tension springs  56  and decreases the tension applied to the variable tension springs  56 . This increases the flex or extension of the variable tension springs  56 , which means the springs  56  and adjacent first bladder  16  will move downward a greater distance when an occupant is seated in the seat  20 . Further, lowering the rear portion of the variable tension springs  56  lowers the height of the seating surface  40 . 
     In operation, and as illustrated in  FIGS. 8-9 , the height and tension of the variable tension springs  56  can be adjusted to counteract a change in the height of the seating surface  40  caused by a selective increase or decrease in the pressure within the first bladder  16 . As described above, deflating the first bladder  16  decreases the height of the first bladder  16 , and therefore lowers the seating surface  40  and the location of the h-point HP. However, as shown in  FIG. 9 , the decrease in height of the first bladder  16  can be compensated for by raising the rear portion of the variable tension springs  56  and increasing the tension on the springs  56 , effectively raising the height of the first bladder  16  when an occupant is seated on the seat  20 . This enables the occupant to select a softer seat cushion  12   a , yet maintain the overall height of the seating surface  40  and location of the h-point HP. As is easily understood, the opposite is true with respect to increasing the firmness of the cushion  12   a . Referring to  FIG. 8 , when increasing the firmness of the cushion  12   a , the first bladder  16  is selectively inflated, and the height and tension of the variable tensions springs  56  is reduced, effectively lowering the height of the first bladder  16  when an occupant is seated upon the seat  20 . Additionally, the seat  20  may include a strain gauge  66  ( FIG. 10 ) for measuring the tension in the variable tension springs  56 , which may be used for automatically controlling the motor  58  and applied tension. 
     The seat back  22  may also have a similar adjustment mechanism, in the form of a back support assembly  68  that is adapted to adjust the position of the first bladder  50 . Referring to the embodiment illustrated in  FIG. 12 , the back support assembly  68  and the first bladder  50  are arranged in a substantially vertical fore/aft relationship where the back support assembly  68  is positioned rearward of the first bladder  50 . The back support assembly  68  includes at least two adjustable lumbar cables  70 , at least two listing wires  72 , and multiple seat springs  74 . The adjustable lumbar cables  70  and listing wires  72  essentially form a frame structure within the upper seat frame  28 , and the seat springs  74  are mounted therebetween. The back support assembly  68  also includes a pair of motors  76  coupled to the adjustable lumbar cables  70 . The motors  76  are adapted to draw in a portion of the length of the adjustable lumbar cables  70 , effectively shortening the cables  70 , which results in less flexibility in the adjustable lumbar cables  70  and a stiffer back support assembly  68 . 
     The back support assembly  68  can be utilized to counteract a change in the position of seat back cushion  12   b  caused by an increase or decrease in the pressure within the first bladder  50 . For example, to obtain a softer seat back cushion  12   b , the occupant can selectively deflate the first bladder  50 , allowing the occupant&#39;s back to sink into the cushion  12   b  to a greater degree. Deflating the first bladder  50  decreases the thickness of the first bladder  50 , and therefore also moves the support surface  54  and location of the h-point HP rearward. The decrease in the thickness of the first bladder  50  can be compensated for by stiffening the back support assembly  68 . Decreasing the length of the adjustable lumbar cables  68  makes the back support assembly  68  less flexible, pushing the first bladder  50  forward and maintaining the location of the support surface  54 . Stated differently, stiffening the back support assembly  68  compensates for the decrease in thickness of the first bladder  50 . This enables the occupant to select a softer seat back cushion  12   b , yet maintain the location of the support surface  54  and h-point HP. As is easily understood, the opposite is true with respect to increasing the firmness of the cushion  12   b . When increasing the firmness of the cushion  12   b , the first bladder  50  is selectively inflated, and the back support assembly  68  is automatically adjusted by increasing the length of the adjustable lumbar cables  70 . 
     In yet another embodiment, the seat back  22  has an adjustment mechanism, in the form of a back support assembly  80 , which is similar to the back support assembly  68  described above. Referring to the embodiment illustrated in  FIG. 13 , the back support assembly  80  includes two cables  82 , at least two listing wires  84 , multiple seat springs  86 , and a listing post  88 . The listing wires  72  are mounted between a top portion of the upper seat frame  28  and the substantially horizontal listing post  88 , essentially forming a frame structure within which the seat springs  86  are disposed. The upper seat frame  28  includes a rotating tube  90  that extends between the lateral sides of the frame  28  and which is disposed at a lower portion thereof. The cables  82  are coupled to both the rotating tube  90 , at their lower end, and to the listing post  88 , at their upper end. The cables are held in tension between the rotating tube  90  and the listing post  88 . The back support assembly  80  also includes a motor  92  and gear  94  which are operably coupled to the rotating tube  90  and positioned in a lower portion of the upper seat frame  28 . The motor  92  and gear  94  are adapted to rotate the rotating tube  90 , which winds the cables  82  around the rotating tube  90  and pulls the listing post  88  downward. This puts the listing wires  84  into greater tension, which decreases the flexibility of the back support assembly  89 , resulting in stiffer back support. Stiffening the back support assembly  80  compensates for a decrease in thickness of the first bladder  50  as selectively adjusted by the occupant, in the same manner as described above relative to the prior embodiment. 
     It will be understood by one having ordinary skill in the art that construction of the described invention and other components is not limited to any specific material. Other exemplary embodiments of the invention disclosed herein may be formed from a wide variety of materials, unless described otherwise herein. 
     For purposes of this disclosure, the term “coupled” (in all of its forms, couple, coupling, coupled, etc.) generally means the joining of two components (electrical or mechanical) directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally formed as a single unitary body with one another or with the two components. Such joining may be permanent in nature or may be removable or releasable in nature unless otherwise stated. 
     It is also important to note that the construction and arrangement of the elements of the invention as shown in the exemplary embodiments is illustrative only. Although only a few embodiments of the present innovations have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of the interfaces may be reversed or otherwise varied, the length or width of the structures and/or members or connector or other elements of the system may be varied, the nature or number of adjustment positions provided between the elements may be varied. It should be noted that the elements and/or assemblies of the system may be constructed from any of a wide variety of materials that provide sufficient strength or durability, in any of a wide variety of colors, textures, and combinations. Accordingly, all such modifications are intended to be included within the scope of the present innovations. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the desired and other exemplary embodiments without departing from the spirit of the present innovations. 
     It will be understood that any described processes or steps within described processes may be combined with other disclosed processes or steps to form structures within the scope of the present invention. The exemplary structures and processes disclosed herein are for illustrative purposes and are not to be construed as limiting. 
     It is also to be understood that variations and modifications can be made on the aforementioned structures and methods without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.