Patent Publication Number: US-2005140196-A1

Title: Round recliner for vehicle

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a recliner mounted in a seat of a vehicle for controlling an angle of inclination of the back of the seat, and more particularly to a round recliner for a vehicle that is capable of minimizing occurrence of clearances in the recliner and preventing any irregular engagement of the recliner.  
      2. Description of the Related Art  
      As well known to those skilled in the art, one or more seats are provided in a vehicle, on which a driver or a passenger sits comfortably. In the seat are mounted a pair of seat fixing bases actuated by means of a lever for moving a seat back and forth, and a recliner mounted to the rear end of one of the seat fixing bases for rotating the back of the seat back and forth. The recliner is used for the driver or the passenger to adjust a rotational position of the back of the seat based on his/her body form.  
      The aforesaid recliner is usually mounted to one side of the seat fixing base to which an actuating lever is attached. When the vehicle collides with another vehicle or any structure, the back of the seat leans forward. At this time, the back of the seat attached to the seat fixing base where the recliner is not provided leans forward, whereas the back of the seat attached to the seat fixing base where the recliner is provided does not lean forward. As a result, a rotational force is generated about the recliner, and thus a repulsive force and the rotational force are applied to the back of the seat when the driver or the passenger is pushed forwardly.  
      A recliner as shown in  FIG. 8  has been proposed in order to solve the aforesaid problems. As shown in  FIG. 8 , lower fixing members  2  are attached to the rear ends of seat fixing bases  1 , respectively. To the lower fixing members  2  are pivotably attached upper fixing members  4  for controlling a rotating movement of the back of the seat. The recliner comprises a first recliner part having a lower gear  12  rotated by means of a rotational movement of a cam  13  effected by an actuating lever  10  for controlling a rotating movement of the back of the seat, and a second recliner part connected to the first recliner part via a shaft  14 . The second recliner part has a link  15 , by which the second recliner part can be cooperated with the first recliner part. At one of the seat fixing bases  1  is provided a nut hole  16 , which is close to the lower fixing member  2 . A safety belt  17  is fixed to the seat fixing base  1  by means of the nut hole  16 .  
      As described above, the recliner is very complicated in its structure, with the result that the assembly of the recliner is difficult and the cost of manufacturing the recliner is increased. Furthermore, the nut hole provided for fixing the safety belt is formed at the front part of the seat fixing base due to the structure of the lower fixing member. Consequently, the safety belt does not function effectively when the vehicle collides with another vehicle or any structure.  
      Therefore, a recliner as shown in  FIGS. 9 and 10  has been proposed in order to solve the aforesaid problems. As shown in  FIGS. 9 and 10 , the recliner comprises: a lock gear guiding groove  32  formed inside an upper actuating member  30  by means of blanking, in which a lock gear  50  is operatively arranged; an inner gear part  34  formed on the lower inner edge of the lock gear guiding groove  32  by means of the aforesaid blanking, the lock gear  50  being engaged with the inner gear part  34 ; a lock gear actuating groove  42  formed inside a lower supporting member  40  by means of the aforesaid blanking; an inner gear part  45  formed on the lower inner edge of the lock gear actuating groove  42  by means of the aforesaid blanking; a reinforcing portion  44  protruded from the lower supporting member  40 , the reinforcing portions  44  being inserted into the lock gear guiding groove  32  of the upper actuating member  30 , the lock gear  50  being actuated vertically by means of an actuating cam  60  in the lock gear actuating groove  42  of the lower supporting member  40 ; and a cam hole  54  formed in the lock gear  50 , the cam hole  54  having a top end surface  56  and a bottom end surface  58 , the top end surface  56  being in contact with a top end  62  of the actuating cam  60  and the bottom end surface  58  being in contact with a bottom end  64  of the actuating cam  60 , the actuating cam  60  actuating vertically in the cam hole  54  of the lock gear  50 .  
      The upper actuating member  30  and the lower supporting member  40  are securely fixed to each other by means of the lock gear  50 , and the lock gear is actuated in the lock gear guiding groove  32  of the upper actuating member  30  and the lock gear actuating groove  42  of the lower supporting member  40 . Consequently, twisting from side to side is reduced as compared to other conventional recliners even when any impact is applied to the recliner as the vehicle collides with another vehicle from the front or from behind, and thus any breakage of the lock gear  50  is prevented. Since the lock gear  50  and the actuating cam  60  are operated only by means of a shaft  70  in the lower supporting member  40 , however, there is a clearance between the lock gear  50  and the actuating cam  60 , which causes noise and vibration.  
      Furthermore, an outer gear part  52  is engaged with the inner gear part  45  of the lower supporting member  40  as well as the inner gear part  34  of the upper actuating member  30 . Consequently, the assembly operation of the recliner is very difficult, and the engagement of the gear parts may be irregular, which also causes noise and vibration.  
      Moreover, when the recliner is loaded in front thereof or in the rear thereof, not only twisting of the recliner from side to side occurs but also shaking of the recliner occurs, whereby the load is not evenly applied to the outer gear part  52  of the lock gear  50 . Consequently, a degree of strength of the recliner may be decreased, and the recliner may be easily damaged even by a light impact.  
     SUMMARY OF THE INVENTION  
      Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a round recliner for a vehicle, comprising three lock gears evenly spaced apart from each other, each of the lock gears being interposed between a cam and a corresponding lock gear supporting member in such a manner that the lock gears are engaged with a circular inner gear part of a sector gear, thereby minimizing occurrence of clearances in the recliner and preventing any irregular engagement of the recliner.  
      It is another object of the present invention to provide a round recliner for a vehicle, comprising three lock gears, to each of which an external force is applied at a right angle thereto in such a manner that the external force is dispersed at three points, respectively, for evenly distributing the force to inner gear parts of the lock gears so that the strength of each of the inner gear parts of the lock gears is increased, and thus the strength of the recliner is also increased.  
      In accordance with the present invention, the above and other objects can be accomplished by the provision of a round recliner mounted in a seat of a vehicle for controlling an angle of inclination of the back of the seat, the recliner comprising: a sector gear including a circular shaft hole formed so that a rotating shaft is inserted therethrough, a circular inner gear part engaged with outer gear parts of lock gears, a back connection part having a plurality of connection protrusions for connecting the back connection part to the back of the seat, the connection protrusions being spaced a uniform angular distance from each other and also spaced a uniform radial distance from the circular shaft hole, and a lock gear receiving part formed at the inner surface of the sector gear for receiving three lock gears and an actuating cam; a holder combined with the sector gear, the holder including a cam receiving part for receiving connection protrusions of the actuating cam, three lock gear supporting members for supporting the three lock gears, respectively, so that the lock gears are locked or released, a seat connection part having first three connection protrusions and second three connection protrusions for connecting the seat connection part to the seat, each of the first connection protrusions having a diameter different from each of the second connection protrusions, the first connection protrusions being spaced a uniform angular distance from each other and also spaced a uniform radial distance from the center of the seat connection part, the second connection protrusions being spaced a uniform angular distance from each other and also spaced a uniform radial distance from the center of the seat connection part, the first and second connection protrusions being alternately arranged, and a lock gear receiving part formed at the inner surface of the holder for receiving the lock gears; the actuating cam disposed between the sector gear and the cam receiving part of the holder for locking the lock gears in the sector gear or releasing the lock gears from the sector gear by rotation of the rotating shaft; the three lock gears engaged with the inner gear part of the sector gear so that the lock gears are locked or released; a return spring for maintaining the locked state of the actuating cam, i.e., the engagement of the lock gears with the sector gear; and a fixing holder for preventing separation of the assembled sector gear and holder from each other.  
      Preferably, each of the lock gear supporting members includes: first and second sliding supporting surfaces for supporting each of the lock gears so that each of the lock gears is slidably moved on the first and second sliding supporting surfaces; a first blocking supporting surface for supporting each of the lock gears when the lock gears are locked; and a second blocking supporting surface for supporting each of the lock gears when the lock gears are released, and wherein the first and second sliding surfaces and the first blocking supporting surface are formed in the shape of circular arcs each having a rotating point as its center.  
      Preferably, a line extended from the center, i.e., the rotating point, of the first sliding supporting surface of each of the lock gear supporting members to the middle of the outer gear part of each of the lock gears is perpendicular to another line extended from a rotating point of each of the lock gears to the middle of the outer gear part of each of the lock gears.  
      Preferably, the cam receiving part of the holder is provided at the center thereof with a shaft hole, the rotating shaft being inserted through the shaft hole, and the cam receiving part of the holder is provided at the circumference thereof with a spring fixing groove for fixing an outer end of the return spring.  
      Preferably, the actuating cam includes: a rotating shaft insertion hole formed so that a polygonal end of the rotating shaft is inserted therethrough, and so that the actuating cam is rotated together with the rotating shaft; the connection protrusions inserted in the cam receiving part of the cam; a spring fixing groove for fixing an inner end of the return spring; lock gear actuating protrudes for actuating locking protrudes and releasing protrudes of the lock gears, respectively, so that the lock gears are locked in the sector gear or released from the sector gear; and lock gear fixing protrudes for pressing against the locking protrudes of the lock gears, respectively, so that the lock gears are completely fixed to the sector gear.  
      Preferably, the lock gear actuating protrudes and the lock gear fixing protrudes are formed in the shape of steps, respectively, so that the lock gear actuating protrudes and the lock gear fixing protrudes make contact with the lock gears and are separated from the lock gears by means of two step-like point contacts in a step fashion when the lock gears are locked or released. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:  
       FIG. 1  is a perspective view of a seat of a vehicle in which a round recliner according to the present invention is mounted;  
       FIG. 2  is an exploded perspective view of the round recliner according to the present invention;  
       FIGS. 3   a  to  3   d  are detail views of components of the round recliner according to the present invention;  
       FIG. 4  is a partial cutaway view of the round recliner according to the present invention showing the assembled components of the round recliner according to the present invention;  
       FIG. 5  is a bottom view of the round recliner according to the present invention shown in  FIG. 4 ;  
       FIG. 6   a  is a plan view showing the round recliner according to the present invention in a locked state;  
       FIG. 6   b  is a plan view showing the round recliner according to the present invention when its locked state is released;  
       FIG. 7  is a plan view of the round recliner according to the present invention illustrating the operation of the recliner;  
       FIG. 8  is a perspective view of a conventional recliner showing a shaft connected between two opposite links of the recliner;  
       FIG. 9  is an exploded perspective view of another conventional recliner; and  
       FIG. 10  is an assembled perspective view of the recliner of  FIG. 9 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       FIG. 1  is a perspective view of a seat of a vehicle in which a round recliner according to the present invention is mounted,  FIG. 2  is an exploded perspective view of the round recliner according to the present invention, and  FIGS. 3   a  to  3   d  are detail views of components of the round recliner according to the present invention.  
      A round recliner  100  of the present invention is generally mounted in an existing car seat, as shown in  FIG. 1 . The back of the car seat is normally in a locked state. When an angle of inclination of the back of the car seat is to be controlled, a driver releases the locked state of the recliner  100  to control the angle of inclination of the back of the car seat, and then the driver locks again the recliner  100 .  
      As shown in  FIGS. 2 and 3   a  to  3   d , the round recliner  100  of the present invention, which functions as mentioned above, comprises: a sector gear  200 ; a holder  300  combined with the sector gear  200 ; an actuating cam  400 ; three lock gears  500 ; a return spring  600 ; and a fixing holder  700 .  
      The sector gear  200  includes a circular shaft hole  210 , through which a rotating shaft  800  is inserted, a circular inner gear part  220  engaged with outer gear parts of lock gears, a back connection part  230  having a plurality of connection protrusions  231  formed thereon, by which the back connection part  230  is connected to the back of a seat, the connection protrusions  231  being spaced a uniform angular distance from each other and also spaced a uniform radial distance from the circular shaft hole  210 , and a lock gear receiving part  240  formed at the inner surface of the sector gear  200  for receiving three lock gears  500  and an actuating cam  400 .  
      The holder  300  includes a cam receiving part  310  for receiving connection protrusions  420  of the actuating cam  400 , three lock gear supporting members  320  for supporting the three lock gears  500 , respectively, in such a manner that the lock gears  500  are locked or released, a seat connection part  330  having first three connection protrusions  331  and second three connection protrusions  332  formed thereon, by which the seat connection part  330  is connected to the seat, each of the first connection protrusions  331  having a diameter different from each of the second connection protrusions  332 , the first connection protrusions  331  being spaced a uniform angular distance from each other and also spaced a uniform radial distance from the center of the seat connection part  330 , the second connection protrusions  332  being spaced a uniform angular distance from each other and also spaced a uniform radial distance from the center of the seat connection part  330 , the first and second connection protrusions  331  and  332  being alternately arranged, and a lock gear receiving part  340  formed at the inner surface of the holder  300  for receiving the lock gears  500 .  
      The actuating cam  400  is disposed between the sector gear  200  and the cam receiving part  310  of the holder  300  for locking the lock gears  500  in the sector gear  200  or releasing the lock gears  500  from the sector gear  200  by rotation of the rotating shaft  800 .  
      The three lock gears  500  are engaged with the inner gear part  220  of the sector gear  200  in such a manner that the lock gears  500  are locked or released.  
      The return spring  600  is provided for maintaining the locked state of the actuating cam, i.e., the engagement of the lock gears  500  with the sector gear  200 .  
      The fixing holder  700  is provided for preventing separation of the assembled sector gear  200  and holder  300  from each other.  
      The cam receiving part  310  of the holder  300  is provided at the center thereof with a shaft hole  311 , through which the rotating shaft  800  is inserted. The cam receiving part  310  of the holder  300  is provided at the circumference thereof with a spring fixing groove  312  for fixing an outer end  620  of the return spring  600 .  
      Each of the lock gear supporting members  320  includes: first and second sliding supporting surfaces  321  and  322  for supporting each of the lock gears  500  in such a manner that each of the lock gears  500  is slidably moved on the first and second sliding supporting surfaces  321  and  322 ; a first blocking supporting surface  323  for supporting each of the lock gears  500  when the lock gears  500  are locked; and a second blocking supporting surface  324  for supporting each of the lock gears  500  when the lock gears  500  are released. The first and second sliding surfaces  321  and  322  and the first blocking supporting surface  323  are formed in the shape of circular arcs each having a rotating point A as its center (Refer to  FIG. 7 ). Consequently, occurrence of clearances in the recliner is minimized, and thus the quality of the recliner is improved.  
      A line extended from the center, i.e., the rotating point A, of the first sliding supporting surface  321  of each of the lock gear supporting members  320  to the middle of the outer gear part  510  of each of the lock gears  500  is perpendicular to another line extended from a rotating point B of each of the lock gears  500  to the middle of the outer gear part  510  of each of the lock gears  500  (Refer to  FIG. 7 ). Consequently, an external force is applied to each of the three lock gears  500  at a right angle thereto, and the external forces are dispersed at three points, respectively. When the external forces are applied to the three lock gears  500  at right angles thereto at the three points, respectively, the forces are evenly distributed to inner gear parts of the lock gears so that the strength of each of the inner gear parts of the lock gears is increased, and thus the strength of the recliner is also increased.  
      The actuating cam  400  includes: a rotating shaft insertion hole  410 , through which a polygonal end of the rotating shaft  800  is inserted so that the actuating cam  400  is rotated together with the rotating shaft  800 ; the connection protrusions  420  inserted in the cam receiving part  310  of the cam  300 ; a spring fixing groove  430  for fixing an inner end  610  of the return spring  600 ; lock gear actuating protrudes  440  for actuating locking protrudes  530  and releasing protrudes  520  of the lock gears  500 , respectively, so that the lock gears  500  are locked in the sector gear  200  or released from the sector gear  200 ; and lock gear fixing protrudes  450  for pressing against the locking protrudes  530  of the lock gears  500 , respectively, so that the lock gears  500  are completely fixed to the sector gear  200 .  
      The lock gear actuating protrudes  440  and the lock gear fixing protrudes  450  are formed in the shape of steps, respectively, so that the lock gear actuating protrudes  440  and the lock gear fixing protrudes  450  make contact with the lock gears  500  and are separated from the lock gears  500  in a step fashion when the lock gears  500  are locked or released. In other words, the actuating cam  400  makes contact with the lock gears  500  and are separated from the lock gears  500  by means of two step-like point contacts a and b, whereby concentration of stress is prevented, and the shape strength of each of the actuating cam  400  and the lock gears  500  is increased (Refer to  FIG. 6   a ).  
      Each of the lock gears  500  includes: the outer gear part  510  having the same gear size as the inner gear part  220  of the sector gear  200 ; the releasing protrude  520 ; and the locking protrude  530 .  
      When the lock gears  500  are turned along the lock gear supporting members  320  of the holder  300  so that the lock gears  500  are close to the lock gear supporting members  320  of the holder  300 , respectively, the outer gear part  510  of each of the lock gears  500  is disengaged from the inner gear part  220  of the sector gear  200 . Consequently, the lock gears  500  are released. When the lock gears  500  are turned back along the lock gear supporting members  320  of the holder  300  so that the lock gears  500  are far from the lock gear supporting members  320  of the holder  300 , respectively, the outer gear part  510  of each of the lock gears  500  is engaged with the inner gear part  220  of the sector gear  200 . Consequently, the lock gears  500  are locked.  
      The assembling process of the round recliner  100  with the afore-stated construction according to the present invention will now be described with reference to the accompanying drawings.  
       FIG. 4  is a partial cutaway view of the round recliner according to the present invention showing the assembled components of the round recliner according to the present invention, and  FIG. 5  is a bottom view of the round recliner according to the present invention shown in  FIG. 4 . As shown in  FIGS. 4 and 5 , the return spring  600  is arranged around the connection protrusions  420  of the actuating cam  400 . The inner end  610  of the return spring  600  is inserted into the spring fixing groove  430  of the actuating cam  400 , and the outer end  620  of the return spring  600  is inserted into the spring fixing groove  312  of the holder  300 . The connection protrusions  420  are disposed in the cam receiving part  310  of the holder  300 . The rotating shaft  800  is inserted through the shaft hole  210  of the sector gear  200 , the rotating shaft insertion hole  410  of the actuating cam  400 , and the shaft hole  311  of the cam receiving part  310  of the holder  300 , in order, so that the actuating cam is rotated with rotation of the rotating shaft  800 . Each of the three lock gears  500  is disposed at each of the lock gear receiving parts  340  between one of the three lock gear supporting members  320  and the neighboring lock gear supporting member, and the sector gear  200  is attached to the holder  300 . The fixing holder  700  is fitted on the assembled sector gear  200  and the holder  300 , and then outer circumference of the fixing holder  700  is pressed by means of a press. In this way, the assembled recliner  100  is obtained.  
      The operation of the round recliner  100  with the afore-stated construction according to the present invention will now be described with reference to the accompanying drawings.  
       FIG. 6   a  is a plan view showing the round recliner according to the present invention in a locked state, and  FIG. 6   b  is a plan view showing the round recliner according to the present invention when its locked state is released. The recliner  100  of the present invention is locked as shown in  FIG. 6   a . When the rotating shaft  800  is rotated clockwise, the actuating cam  400  is also rotated clockwise. At this time, the lock gear actuating protrudes  440  of the actuating cam  400  push up the releasing protrudes  520  of the lock gears  500 , as shown in  FIG. 6   b , whereby the lock gears  500  are turned along the second sliding supporting surfaces  322  of the lock gear supporting members  320  of the holder  300  to make contact with the second blocking supporting surfaces  324 , respectively. Consequently, the outer gear part  510  of each of the lock gears  500  is disengaged from the inner gear part  220  of the sector gear  200 , and thus the lock gears  500  are released. At this time, the return spring  600  inwardly shrinks to retain a restoring force. Consequently, the rotating shaft  800  must be held in order to keep the recliner  100  of the present invention released.  
      When the rotating shaft  800  is released to lock the recliner  100  of the present invention, the rotating shaft  800  is rotated counterclockwise by means of the restoring force of the return spring  600 . As a result, the actuating cam  400  is also rotated counterclockwise, and returned to the initial position. At this time, the lock gear actuating protrudes  440  of the actuating cam  400  push up the locking protrudes  530  of the lock gears  500 , as shown in  FIG. 6   a , whereby the lock gears  500  are turned back along the first and second sliding supporting surfaces  321  and  322  of the lock gear supporting members  320  of the holder  300  to make contact with the first blocking supporting surfaces  323 , respectively, so that the lock gear fixing protrudes  450  is strongly pressed against the locking protrudes  530  of the lock gears  500 . Consequently, the outer gear part  510  of each of the lock gears  500  is engaged with the inner gear part  220  of the sector gear  200 , and thus the lock gears  500  are locked. At this time, the actuating cam  400  is no longer moved by means of the return spring  600 , whereby the engagement of the lock gears  500  with the sector gear  200  is stably maintained.  
      In brief, the lock gears  500  are turned along the lock gear supporting members  320  of the holder  300  so that the lock gears  500  are close to the lock gear supporting members  320  of the holder  300 , respectively. As a result, the outer gear part  510  of each of the lock gears  500  is disengaged from the inner gear part  220  of the sector gear  200 . Consequently, the lock gears  500  are released. When the lock gears  500  are turned back along the lock gear supporting members  320  of the holder  300  so that the lock gears  500  are far from the lock gear supporting members  320  of the holder  300 , respectively, the outer gear part  510  of each of the lock gears  500  is engaged with the inner gear part  220  of the sector gear  200 . Consequently, the lock gears  500  are locked.  
      The lock gears  500  of the present invention are turned along the supporting surfaces  321 ,  322  and  323  formed at the lock gear supporting members  320  of the holder  300 , whereby clearances between the lock gears  500  and the lock gear supporting members  320  of the holder  300  do not occur, and thus the strength of the recliner of the present invention is increased.  
      As apparent from the above description, the present invention provides a round recliner for a vehicle, comprising three lock gears evenly spaced apart from each other, each of the lock gears being interposed between a cam and a corresponding lock gear supporting member in such a manner that the lock gears are engaged with a circular inner gear part of a sector gear, wherein the lock gears are turned along the lock gear supporting members so that an outer gear part of each of the lock gears is disengaged from the inner gear part of the sector gear or the outer gear part of each of the lock gears is engaged with the inner gear part of the sector gear, thereby minimizing occurrence of clearances in the recliner and preventing any irregular engagement of the recliner.  
      Furthermore, a line extended from a rotating point of a first sliding supporting surface of each of the lock gear supporting members to the middle of the outer gear part of each of the lock gears is perpendicular to another line extended from a rotating point of each of the lock gears to the middle of the outer gear part of each of the lock gears, whereby an external force is applied to each of the three lock gears at a right angle thereto, and the external forces are dispersed at three points, respectively. Consequently, the forces are evenly distributed to inner gear parts of the lock gears so that the strength of each of the inner gear parts of the lock gears is increased, and thus the strength of the recliner is also increased.  
      Although the preferred embodiments of the present invention have been disclosed 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.