Abstract:
A seat sliding apparatus for vehicles is provided. The seat sliding apparatus includes a track and a guide bracket with legs connected to stepped locking pins to regulate the locked state of the locking pins which engage the track. In one embodiment, the track includes through-holes which are engaged by the locking pins. Accordingly to another aspect of the apparatus, a plastic bushing is provided to prevent horizontal/vertical floating of the locking pins, thereby minimizing the play of the locking pins and prevent floating. The apparatus also may simultaneously prevent a half-locked state of the locking pins.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims priority to and the benefit of Korean Patent Application 10-2005-0101194 filed in the Korean Intellectual Property Office on Oct. 26, 2005, the entire content of which is incorporated herein by reference.  
       FIELD OF THE INVENTION  
       [0002]     The present invention relates generally to a seat sliding apparatus for vehicles, and more particularly to a seat sliding apparatus that prevents a half-locked state of the seat to a seat track that may be caused by the play of locking pins.  
       DESCRIPTION OF THE RELATED ART  
       [0003]     In a vehicle, the front driver and passenger seats are generally movable in a forward or backward direction to allow the driver or passenger to sit in a particular position. In order to move the seat in a forward or backward direction, a user raises a lever upward causing locking pins  8  to escape from slots in a seat track and releasing the locked state thus enabling the seat to move.  
       SUMMARY OF THE INVENTION  
       [0004]     In one embodiment, the present invention provides a seat sliding apparatus for vehicles in which a guide bracket is connected to stepped locking pins such that when any one of four locking pins is not locked, the steps of the locking pins push against arms of the guide bracket to prevent engagement of the locking pins with the track. In another embodiment, a clamping bushing is mounted in a transfer rail so as to allow the locking pins to be firmly positioned, thereby preventing horizontal/vertical floating of the locking pins as well as minimizing the play of the locking pins.  
         [0005]     In one embodiment, the apparatus includes a lever operable to move upward and downward to facilitate a seat to move in a forward or backward direction; a connecting bar hinged to a seat fixture to promote the upward and downward operation of the lever; a guide bracket pivoting according to operation of the lever and the connecting bar; locking pins inserted and extracted into and from through-holes of a track by the pivoting action of the guide bracket; and a supporting member mounted to a transfer rail, the support member comprising a hinge pin that supports the guide bracket and also having through-holes for the locking pins.  
         [0006]     In one aspect, the present invention is directed to a seat sliding apparatus for vehicles, comprising a lever operable to move upward and downward to facilitate a seat moving forward and backward directions, a connecting bar hinged to a fixture to promote the upward and downward operation of the lever, a guide bracket pivoting in response to operation of the lever and the connecting bar, a plurality of locking pins inserted into and extracted from a plurality of first through-holes on a track by the pivoting of the guide bracket, wherein the plurality of locking pins are inserted into the through-holes in unison, and a supporting member mounted to a transfer rail and pivotably supporting the guide bracket using a hinge pin, said supporting member comprising a plurality of second through-holes for the operation of the locking pins.  
         [0007]     In other aspects, one of the plurality of locking pins being unable to enter a through-hole prevents the remaining locking pins from entering through-holes; the lever is coupled with the guide bracket by a connecting piece; the connecting piece is provided with a receiving recess for connecting the lever; the connecting bar is mounted with one or more torsion springs for promoting upward and downward operation; the guide bracket is provided with a plurality of legs spaced apart from each other and which support the locking pins; the plurality of legs comprise first legs of a linear shape and second legs whose middle portions are bent in a semi-circular shape, alternating with each other; each of the plurality of locking pins comprises a first projection and a second projection, wherein the space between the first and second projections defines a space capable of receiving the second legs; each of the plurality of locking pins is connected to a spring adapted to insert the locking pin into a through-hole, said spring being installed between the second projection and the supporting member; the apparatus further comprises a clamping bushing to prevent floating of any of the plurality of locking pins; the clamping bushing comprises third through-holes through which the locking pins pass, said clamping bushing located between the track and the guide bracket; the clamping bushing is held in place with a plurality of locking members; and the clamping bushing is formed of plastic.  
     
    
     DESCRIPTION OF THE DRAWINGS  
       [0008]     The above and other objectives, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:  
         [0009]      FIG. 1  is a perspective view illustrating an embodiment of the disclosed seat sliding apparatus;  
         [0010]      FIG. 2  is a magnified perspective view of portion A as shown in  FIG. 1 ;  
         [0011]      FIG. 3  is a perspective view showing a seat sliding apparatus with a clamping bushing mounted; and  
         [0012]      FIG. 4  is a perspective view illustrating an embodiment of the disclosed seat sliding apparatus.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0013]     In the Figures and the following description the same reference numerals are used to designate the same or similar components. As shown in  FIGS. 1 and 2 , a seat sliding apparatus is comprised of lever  10 , connecting bar  20 , guide bracket  30 , locking pin  40 , supporting member  50 , and clamping bushing  60 . Lever  10  is operable to move upward and downward, and is adapted to press on guide bracket  30  to move locking pins  40  to in horizontal (i.e., leftward and rightward) directions. When the locking pins are released, the seat is free to move in the forward and backward directions, and when the locking pins are engaged, the seat is locked in a particular position on track  1 .  
         [0014]     In one embodiment, lever  10  is connected to connecting bar  20  and also to guide bracket  30 . In another embodiment, connecting piece  12  is provided with a receiving recess  14  in which the lever  10  is rested and coupled, and a hole  16  for coupling connecting bar  20  to connecting piece  12 . As will be recognized, receiving recess  14  facilitates operation of the lever  10  after coupling, and as shown by the arrow in  FIG. 2 , lever  10  is operable to move upward and downward. In various embodiments, lever  10  may be coupled with guide bracket  30  by connecting piece  12 ; connecting piece  12  may be provided with receiving recess  14  for resting and fitting lever  10  on one side thereof; and connecting bar  12  may be mounted with torsion springs  22  for promoting upward and downward operation.  
         [0015]     As shown, connecting bar  20  passes through hole  16  of connecting piece  12  and connects to fixture  3  facilitating the upward and downward operation of the lever  10 . In one embodiment, and as shown in  FIG. 3 , connecting bar  20  is mounted with torsion springs  22  for promoting upward and downward operation. Torsion springs  22  are preferably supported by supporting pieces  24  mounted to fixture  3 .  
         [0016]     In one embodiment, guide bracket  30  pivots according to the operation of lever  10 . For example, the upward movement of lever  10  causes a downward movement of connecting piece  12 , which in turn pushes down on guide bracket  30  causing the guide bracket to pivot and push locking pins  40  from the engaged (locked) position. The downward movement of level  10  allows the locking pins to be inserted into through-holes formed in the track  1 . In one embodiment, guide bracket  30  is coupled with a supporting member  50  by means of a hinge pin  54 , and thus pivots up and down about hinge pin  54 .  
         [0017]     In one embodiment, guide bracket  30  comprises a plurality of legs  32  which are spaced apart from each other and also support locking pins  40 . In one embodiment, and as shown in  FIGS. 3 and 4 , legs  32  are comprised of first legs  32 - 1  (in a linear shape) and second legs  32 - 2  (in a semi-circular shape). As will be recognized, the first legs  32 - 1  and second legs  32 - 2  can alternate with each other in shape and location. As shown in  FIG. 2 , each of the first legs  32 - 1  is located outside the first projection  41  of each locking pin  40 , and each of the second legs  32 - 2  is located within the space  44  defined between the first projection  41  and the second projection  42 . In one embodiment, the legs  32  support the locking pins  40  and simultaneously allow the locking pins  40  to move in the leftward and rightward (horizontal) directions.  
         [0018]     In one embodiment, locking pins  40  may be provided with a first projection  41  formed between the first and second legs  32 - 1  and  32 - 2 , and a second projection  42  formed apart from the first projection  41  at a predetermined interval, in order to define a space  44  in which the second leg  32 - 2  is received. Locking pins  40  are preferably fixed so as not to escape from the legs  32 . In this and other embodiments, if any of the locking pins is not positioned to be inserted into through-holes in track  1 , first legs  32 - 1  and/or second legs  32 - 2  press against first projection  41  and/or second projection  42  (respectively) to prevent any of the locking pins from inserting into through-holes in track  1 . Accordingly, all locking pins  40  must be aligned with a through-hole to lock the pins to track  1 . This ensures that the strength of all locking pins contribute to holding the seat in the track in the event of a collision. As will be recognized, although the number of the locking pins  40  is shown as four, any number of locking pins may be used.  
         [0019]     As shown in the Figures, a spring  43  promoting restoration of each locking pin  40  is installed between the second projection  42  and the supporting member  50 . The springs  43  preferably allow the locking pins  40  to be extracted from the through-holes formed on track  1  so as to be able to move a seat, and when the seat moves to a proper position, and lever  10  is moved downward, springs  43  cause the locking pins  40  to be inserted into through-holes in the track  1 . Supporting member  50  preferably comprises a plurality of holes  56  into which a hinge pin  54  can be fitted to support guide bracket  30 , second through-holes  52  (corresponding to the number of locking pins  40 ). Further, supporting member  50  is preferably mounted to transfer rail  2 .  
         [0020]     In one embodiment, supporting member  50 , in conjunction with hinge pin  54 , pivotably supports the guide bracket  30 , and allows locking pins  40  to be extracted from the through-holes in the track  1 . In this and other embodiments, when locking pins  40  are extracted from the through-holes in track  1 , the locking pins may pass through second through-holes  52  in supporting member  50 .  
         [0021]     In another embodiment, and as shown in  FIG. 3 , locking pins  40  are mounted to clamping bushing  60  prevent floating of the locking pins. Clamping bushing  60  is preferably is formed with third through-holes  62  through which the locking pins  40  pass. Further, clamping bushing  60  is preferably installed between track  1  guide bracket  30 . In one embodiment, clamping bushing  60  is provided with locking members  64  to prevent separation of locking pins  40  which may pass through third through-holes  62 . In another embodiment, clamping bushing  60  is formed of plastic.  
         [0022]      FIG. 4  is a perspective view illustrating an embodiment of the disclosed seat sliding apparatus. When an occupant of a vehicle raises lever  10  upward as shown in  FIG. 1 , the upward movement of lever  10  causes guide bracket  30  to pivot around the axis created by hinge pin  54 . As shown in  FIG. 4 , when connecting piece  12  moves downward (arrow A of  FIG. 4 ), guide bracket  30  pivots and legs  32  move (arrow B of  FIG. 4 ) to disengage the locking pins from track  1 , and release the locked state (arrow C of  FIG. 4 ). In one embodiment, when the locking pins  40  are released from the locked state, the occupant moves the seat along the track  1  in a forward or backward direction.  
         [0023]     When the seat moves to desired position, the occupant lowers the lever  10  downward, elastic springs  43  force locking pins  40  into the through-holes of the track  1  re-engaging the locking position. In one embodiment, since guide bracket  30  comprises legs  32 , and locking pins  40  each comprise first projections  41  and second projections  42 , the locking mechanism only functions when all of the locking pins can be inserted into through-holes in track  1 . I.e., where one or more locking pins has no corresponding through-hole, the first and second projections ( 41  and  42  respectively)—which are connected to legs  32  of guide bracket  30 , will prevent any remaining locking pins entering through-holes in track  1 .  
         [0024]     In other embodiments, the size of the locking pins is sufficient so as to meet safety standards for seat sliding mechanisms; the locking pins can only lock in unison, and where one locking pins cannot lock, the remaining pins are prevented from being locked as well; clamping bushing  60  supports locking pins preventing (1) a half-locked state, (2) play of the locking pins, (3) noise caused by the floating of the locking pins.  
         [0025]     Although exemplary embodiments of the present invention have been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.