Patent Publication Number: US-2022219569-A1

Title: Long rail assembly with triple rail configuration

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to and all the benefits of U.S. Provisional Patent Application No. 62/842,687, filed May 3, 2019, and entitled “Long Rail Assembly with Triple Rail Configuration,” the disclosure of which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a long rail assembly that adjusts the position of a seat assembly within a vehicle. 
     2. Description of Related Art 
     Many vehicles today have systems that give seats the capability of power adjustment. For example, adjustable seat assemblies in vehicles incorporate various parts that take the mechanical energy generated by a motor and use it to move the seat. These systems often include multiple power drive assemblies that automatically drive the seat along tracks or channels in the vehicle floor. Often times there is a potential for synchronization issues between the multiple drive assemblies as well as a lack of strength and stability. Furthermore, the more mechanical and moving parts you have the higher risk there is for malfunction due to mechanical failure. 
     SUMMARY OF THE INVENTION 
     According to one embodiment, there is provided a long rail assembly for repositioning a seat assembly in a vehicle comprising an inboard lower channel, an inboard manual drive assembly, an outboard lower channel, an outboard manual drive assembly, a central lower channel, and a power drive assembly. The inboard lower channel is adapted to extend longitudinally along a floor of the vehicle. The inboard manual drive assembly is coupled to the seat assembly and slidably coupled to the inboard lower channel The outboard lower channel is adapted to extend longitudinally along the floor of the vehicle. The outboard manual drive assembly is coupled to the seat assembly and slidably coupled to the outboard lower channel. The central lower channel is adapted to extend longitudinally along the floor of the vehicle. The power drive assembly is coupled to the seat assembly and slidably coupled to the central lower channel. The power drive assembly power drives the seat assembly along the central lower channel. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Advantages of the present disclosure will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein: 
         FIG. 1  is a fragmentary perspective view of a vehicle interior including seat assemblies and long rail assemblies according to one embodiment of the present invention; 
         FIG. 2  is a partially transparent perspective view of a long rail assembly according to one embodiment of the present invention; 
         FIG. 3  is a cross-sectional end view of a manual long rail assembly according to one embodiment of the present invention; 
         FIG. 4  is an exploded perspective view of the manual long rail assembly of  FIG. 3 ; 
         FIG. 5  is a partially transparent cross-sectional end view of a power long rail assembly according to one embodiment of the present invention; 
         FIG. 6  is an exploded perspective view of the power long rail assembly of  FIG. 5 ; and 
         FIG. 7  is a cross-sectional end view of the long rail assembly according to one embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       FIG. 1  illustrates an interior  8  of a vehicle with a plurality of long rail assemblies  10  configured to reposition a plurality of seat assemblies  12  along a floor  14  of the vehicle according to embodiments described herein. Each seat assembly  12  includes a seat cushion  20  and a seat back  22  operatively coupled to the seat cushion  20  for supporting a seat occupant in a generally upright seating position. Each seat assembly  12  also includes a mounting structure  24  that supports the seat cushion  20  above the vehicle floor  14 . The mounting structure  24  includes an inboard rear leg  26 , an outboard rear leg  26 ′, a central rear leg  30  and may also include front legs  32 . 
     Each long rail assembly  10  includes an inboard manual long rail assembly  34 , an outboard manual long rail assembly  34 ′ and a central power long rail assembly  36 . The inboard manual long rail assembly  34  includes an inboard U-shaped lower channel  40  and an inboard manual drive assembly  50  slidably coupled to the inboard lower channel  40 . Likewise, the outboard manual long rail assembly  34 ′ includes an outboard U-shaped lower channel  40 ′ and an outboard manual drive assembly  50 ′ slidably coupled to the outboard lower channel  40 ′. The central power long rail assembly  36  includes a central U-shaped lower channel  44  and a power drive assembly  52  slidably coupled to the central lower channel  44 . The lower channels  40 ,  40 ′,  44  are adapted to be fixedly secured to the vehicle floor  14 . The inboard and outboard rear legs  26 ,  26 ′ are adapted to be fixedly attached to the manual drive assemblies  50 ,  50 ′ and the central rear leg  30  is adapted to be fixedly attached to the power drive assembly  52 . Alternatively, the rear legs  26 ,  26 ′ may be releasably attached to the manual drive assemblies  50 ,  50 ′ and the central rear leg  30  may be releasably attached to the power drive assembly  52 . The seat assembly  12  may be adjusted among a plurality of fore/aft seating positions along the vehicle floor  14 . For example, the seat assembly  12  may be repositioned from a first seat location  54  to a second seat location  56  by power driving the power drive assembly  52  along the central lower channel  44 . Although described in terms of the components for the inboard manual long rail assembly  34 , the present invention includes corresponding structures on the outboard manual long rail assembly  34 ′ represented by like primed reference numerals. Additional details regarding long rail assemblies for use in automotive vehicles are fully set forth in Applicant&#39;s co-pending application no. PCT/US20/22908, entitled “Long Rail Assembly with Internal Power Driving System,” filed Mar. 16, 2020, and co-pending application no. PCT/US19/55835, entitled “Long Rail Assembly for Vehicle Seat Adjustment,” filed Oct. 11, 2019, the disclosures of which are hereby incorporated by reference in their entirety. 
     Referring to  FIGS. 2, 5, 6 and 7 , the central lower channel  44  includes opposing sidewalls  60 ,  62 , a top wall  64  and a bottom wall  66  extending between the opposing sidewalls  60 ,  62 . The top wall  64  includes an elongated opening  68  extending in a longitudinal direction. Each sidewall  60 ,  62  of the central lower channel  44  is bent into a C-shaped cross-section in profile to form tracks  70 ,  72  respectively. The bottom wall  66  of the central lower channel  44  is configured to be fixedly attached to the vehicle floor  14 . 
     The power drive assembly  52  includes an inverted U-shaped central upper channel  80  slidably coupled to the central lower channel  44 . The central upper channel  80  includes a pair of opposing sidewalls  84 ,  86  and a top wall  88  extending therebetween. The power drive assembly  52  also includes front and rear axles  90 ,  92  operatively coupled to the sidewalls  84 ,  86  of the central upper channel  80  and opposing rollers  94  that are coupled to the respective opposite ends of each axle  90 ,  92 . The rollers  94  are configured to travel along the tracks  70 ,  72  of the central lower channel  44 . 
     Referring to  FIGS. 5, 6, and 7 , the power drive assembly  52  further includes a gearbox  82  fixedly secured to and housed within the central upper channel  80 . Preferably, the gearbox  82  is mounted to the top wall  88  of the central upper channel  80 . The gearbox  82  includes a vertically oriented worm gear  100  meshingly engaged with a worm wheel  102 , both of which are rotationally supported within a gearbox housing  104 . 
     The power drive assembly  52  also includes a drive shaft  120  and a pinion  122 . A first end  130  of the drive shaft  120  is fixedly coupled to the worm wheel  102 , and an opposite second end  132  of the drive shaft  120  is fixedly coupled to the pinion  122 . The drive shaft  120  extends out of an opening  133  in the gearbox housing  104  and through a notch  134  in the sidewall  84  of the central upper channel  80 . 
     The central power long rail assembly  36  further includes a rack  124  fixedly coupled to the top wall  64  of the central lower channel  44 . The rack  124  includes a plurality of generally equally spaced apart gear teeth  136  extending along the length of the rack  124  in a longitudinal direction. The gear teeth  136  are oriented towards or facing the bottom wall  66  of the central lower channel  44 . The pinion  122  is oriented in a vertical position to meshingly engage with the gear teeth  136  of the rack  124 . 
     The gearbox  82 , the rack  124  and pinion  122 , are packaged inside the central power long rail assembly  36  to conceal it from any dirt and debris that may accumulate on the vehicle floor  14 . In particular, because the gearbox  82  is mounted within the central upper channel  80 , the upper channel  80  will prevent any dirt or debris from falling directly into gearbox  82 . Similarly, because the rack  124  is mounted within the central lower channel  44  and the gear teeth  136  of the rack  124  are facing downward, any dirt or debris that enters the central lower channel  44  will not settle on the gear teeth  136 . Moreover, because the gearbox  82 , the rack  124  and the pinion  122  are elevated above the bottom wall  66  of the central lower channel  44 , they are not likely to collect any dirt or debris that may accumulate in the central lower channel  44 . 
     Referring to  FIG. 7  the long rail assembly  10  further includes an electric motor  140 . A flexible shaft  142  operatively couples an output shaft  144  of the motor  140  to the worm gear  100 . The flexible shaft  142  extends from the output shaft  144  through an opening  150  in the top wall  88  of the central upper channel  80  and an opening  152  in the gearbox housing  104  to the worm gear  100 . The motor  140  may be mounted anywhere on the seat assembly  12 . For example, the motor  140  may be mounted to the bottom of the seat cushion  20 . 
     Referring to  FIGS. 2, 5, 6, and 7 , the central power long rail assembly  36  further includes a cable  160  housed within a cable carrier  162  within the central lower channel  44 . Because the central lower channel  44  accommodates the cable  160  within the cable carrier  162 , the central lower channel  44  has a wider cross-section than the cross section of the inboard lower channel  40 . The cable carrier  162  includes a plurality of hollowed out segments  164 . Each segment  164  of the cable carrier  162  is flexibly coupled to an adjacent segment  164  to allow the segments  164  to flex and fold relative to one another as the central upper channel  80  slides along the central lower channel  44 . The cable carrier  162  has a first end  168  that is fixedly attached to the sidewall  60  of the central lower channel  44 . A bracket  174  fixedly attaches a second opposite end  172  of the cable carrier  162  to a back end  176  of the sidewall  84  of the central upper channel  80 . The cable  160  enters the cable carrier  162  from the vehicle floor  14  through an opening  170  in the sidewall  60  of the central lower channel  44 . The cable  160  provides power to the motor  140  and the seat assembly  12 , and transmits data between the vehicle and the seat assembly  12 . 
     Referring to  FIGS. 2, 3, 4 and 7 , the inboard lower channel  40  includes opposing sidewalls  190 ,  192 , a top wall  194  and a bottom wall  196  extending between the opposing sidewalls  190 ,  192 . The top wall  194  includes an elongated opening  198  extending in a longitudinal direction. Adjustment notches  268  extend downwardly from the top wall  194  at the opening  198 . Each sidewall  190 ,  192  of the inboard lower channel  40  is bent into a C-shaped cross-section in profile to form tracks  200 ,  202  respectively. The bottom wall  196  of the inboard lower channel  40  is configured to be fixedly attached to the vehicle floor  14 . 
     The inboard manual drive assembly  50  includes an inverted U-shaped inboard upper channel  210  slidably coupled to the inboard lower channel  40 . The inboard upper channel  210  includes a pair of opposing sidewalls  214 ,  216  and a top wall  218  extending therebetween. A portion of the sidewall  214  of the inboard upper channel  210  is bent upward to form an outer channel wall  220  spaced apart from the sidewall  214  and defines a generally U-shaped channel  222  therebetween. A plurality of generally inverted U-shaped slots  224 , are arranged in the sidewall  214  of the inboard upper channel  210  and spaced apart in the longitudinal direction of the inboard upper channel  210 . Generally vertical notches  226  are spaced along the outer channel wall  220  and laterally aligned with the U-shaped slots  224  in the sidewall  214 . 
     The inboard manual drive assembly  50  also includes stability rollers  212  projecting from the sidewalls  214 ,  216  of the inboard upper channel  210  and an extension spring  248  to bias the stability rollers  212  against the respective sidewalls  190 ,  192  of the inboard lower channel  40 . The stability rollers  212  may project from the sidewalls  214 ,  216  at an angle to counteract both vertical and lateral tolerance variations between the inboard upper channel  210  and the inboard lower channel  40  within the inboard manual long rail assembly  34 . 
     The inboard manual drive assembly  50  further includes front and rear axles  228 ,  230  operatively coupled to the sidewalls  214 ,  216  of the inboard upper channel  210  and opposing structural wheels  232  that are coupled to the opposite respective ends of each axle  228 ,  230 . The structural wheels  232  support the seat assembly  12  and the inboard upper channel  210  as they slide along the inboard lower channel  40 . A central portion  234  of each axle  228 ,  230  is slightly larger in diameter than the rest of the axle  228 ,  230 . The larger central portion  234  assures that the axles  228 ,  230  are properly centered and stable relative to the inboard upper channel  210 . The structural wheels  232  are configured to travel along the tracks  200 ,  202  of the inboard lower channel  40 . 
     Referring to  FIGS. 3, 4 and 7 , the inboard manual long rail assembly  34  includes a loop latch system  250  to releasably couple the inboard manual drive assembly  50  to the inboard lower channel  40 . The loop latch system  250  includes a loop latch  252  and a latch release mechanism  254 . The loop latch  252  includes a release trigger  264  and a spring  266 . The spring  266  biases the loop latch  252  into a locked position, thereby preventing the inboard manual drive assembly  50  from sliding along the inboard lower channel  40 . A downward force on the release trigger  264  actuates the loop latch  252  into an unlocked position and unlocks the inboard manual drive assembly  50  from the inboard lower channel  40 , thus allowing the inboard manual drive assembly  50  to slide along the inboard lower channel  40 . 
     The latch release mechanism  254  includes a latch motor  270  and a plunger  272  operatively coupled to the latch motor  270 . The plunger  272  extends through an opening  274  in the top wall  218  of the inboard upper channel  210 , and is generally vertically aligned with the release trigger  264  of the loop latch  252  for selectively engaging the release trigger  264  and actuating the loop latch  252  between the locked and unlocked positions. Additional details regarding the loop latch system  250  for use in a long rail assembly are fully set forth in Applicant&#39;s co-pending application no. PCT/US19/66701, entitled “Loop Latch Release For Power Long Rail Assembly,” filed Dec. 17, 2019, the disclosure of which is hereby incorporated by reference in its entirety. 
     Referring to  FIG. 7 , the long rail assembly  10  further includes an electronic control unit (“ECU”)  278  operatively coupled to the latch motors  270 ,  270 ′ and the motor  140 . The ECU  278  may be coupled to the latch motors  270 ,  270 ′ and/or the motor  140  via an electrical cable  276 . Alternatively, the ECU  278  may be wirelessly connected to the latch motors  270 ,  270 ′ and/or the motor  140 . 
     In operation, the ECU  278  initially actuates the latch motors  270 ,  270 ′ to cause the plungers  272 ,  272 ′ to unlock the loop latches  252 ,  252 ′ on the manual long rail assemblies  34 ,  34 ′. Once unlocked, the manual drive assemblies  50 ,  50 ′ are able to slide along the inboard/outboard lower channels  40 ,  40 ′. The ECU  278  then actuates the motor  140 . The rotation of output shaft  144  of the motor  140  rotates the flexible shaft  142  causing the worm gear  100  to rotate. Rotation of the worm gear  100  is transferred to the worm wheel  102  through their meshing engagement. The drive shaft  120  transfers the rotation of the worm wheel  102  to the pinion  122 . The rotation of the pinion  122  along the rack  124  transposes the central upper channel  80  along the central lower channel  44 , thereby moving the seat assembly  12  along the long rail assembly  10  in a first direction. Reversing the rotational direction of the motor  140  results in the pinion  122  rotating in an opposite direction along the rack  124 , thus moving the central upper channel  80 , and the corresponding seat assembly  12 , along the central lower channel  44  in an opposite direction. After the seat assembly  12  reaches the desired location along the vehicle floor  14 , the ECU  278  deactivates the motor  140  to stop movement of the seat assembly  12 . The ECU  278  then actuates the latch motors  270 ,  270 ′ to cause the plungers  272 ,  272 ′ to release the loop latches  252 ,  252 ′ and lock the manual drive assemblies  50 ,  50 ′ onto the inboard/outboard lower channels  40 ,  40 ′. Pulse width modulation of the motor  140  may provide a more comfortable adjustment speed when the seat assembly  12  is occupied, and a quicker adjustment speed when the seat assembly  12  is unoccupied. 
     The present invention removes the power drive functionality from the inboard and outboard drive assemblies  50 ,  50 ′ and consolidates them into one central power drive assembly  52 . Reducing the number of power drive assemblies  52  required for each seat assembly  12  not only reduces costs, but it also reduces the number of mechanical parts required, and thus reduces the chances that the system will succumb to mechanical failure. In addition, when two independent power drive assemblies are required to drive a seat assembly  12 , the two assemblies must be synchronized in order for the system to work properly. Therefore, the present invention eliminates the need to synchronize multiple power drive assemblies. 
     The present invention also allows for the optimization of the long rail assembly  10 . By separating the power drive functionality, the present invention allows the central power long rail assembly  36  to be optimized for packaging the electrical and power components. Likewise, the manual long rail assemblies  34 ,  34 ′, which take all of the load from the seat assembly  12  and the occupant, are no longer hindered by the space requirements needed for the power drive assembly  52  components, and may be better optimized for strength and stability to absorb the variation from the seat structure and road input. 
     Finally, separating the power drive functionality facilitates the maintenance and repair of the long rail assemblies  10  because any problems in the power drive system may be addressed by replacing or repairing a single central power drive assembly  52  without having to replace or maintain any of the components from the manual drive assemblies  50 ,  50 ′. Finally, the present invention facilitates the transition from a power-driven system to a manual system by simply removing the central power long rail assembly  36 . 
     The invention has been described in an illustrative manner, and it is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced other than as specifically described.