Locking device for an adjustment unit of a motor vehcile seat

Abstract

A locking device for an adjustment unit of a motor vehicle seat having a toothed bar, a locking part cooperating with the toothed bar, a spring that abuts the locking part and a base part. The locking part comprises at least one tooth for engaging the toothed bar. A mass body is associated with the locking part and is hinged to the base part for pivotal movement about an axis. The mass body has a control contour which comprises a) a flat bight portion with a base, b) at least one enabling inclined portion adjoining the bight portion, c) a transition region adjoining the enabling inclined portion and d) one retaining inclined portion adjoining the transition region. The spring fits at one abutment end against the base of the control contour in the normal position of the locking part; the abutment end is capable of moving along the control contour.

1 . A locking device for an adjustment unit of a motor vehicle seat comprising:
 a toothed bar, a locking part cooperating with said toothed bar, a spring that abuts said locking part and a base part, said locking part comprising at least one tooth for engagement into said toothed bar and a mass body, said mass body is associated with said locking part and is hinged to said base part for pivotal movement about an axis, wherein said mass body has a control contour, said control contour comprises a) a flat bight portion with a base, b) at least one enabling inclined portion adjoining said bight portion, c) a transition region adjoining said enabling inclined portion and d) one retaining inclined portion adjoining said transition region, in a normal position of said locking part said spring fits at one abutment end against said base of said control contour, said abutment end being capable of moving along said control contour and moving from said base to said retaining inclined portion in an event of a crash.   
   
   
       2 . The locking device as set forth in  claim 1 , wherein said base extends at a right angle with respect to a direction of a force, and the spring acts onto the base with said force. 
   
   
       3 . The locking device as set forth in  claim 1 , wherein said retaining inclined portion extends at a first angle with respect to said base, said enabling inclined portion extends at a second angle with respect to said base, a course of said enabling inclined portion intersects a course of said retaining inclined portion at an acute angle, and an angle between said base and said enabling inclined portion is smaller than an angle between said base and said retaining inclined portion. 
   
   
       4 . The locking device as set forth in  claim 1 , wherein said spring is a leg spring. 
   
   
       5 . The locking device as set forth in  claim 4 , wherein a guide opening is provided in said base part, said leg spring has a free end, and said free end of said leg spring engages into said guide opening. 
   
   
       6 . The locking device as set forth in  claim 1 , wherein at least one of said control curve and said spring comprise a coating that fixes a definite value of friction. 
   
   
       7 . The locking device as set forth in  claim 1 , wherein a roll body is provided, said roll body is placed onto said abutment end of said spring. 
   
   
       8 . The locking device as set forth in  claim 1 , wherein said control contour is symmetrical with respect to a plane through a contact point of said spring with said base and a direction of the spring force, said plane extending parallel to said axis. 
   
   
       9 . The locking device as set forth in  claim 1 , wherein said toothed bar has tooth flanks, said at least one tooth of said locking part abuts said tooth flank in an event of a crash, said tooth flank extends substantially perpendicular to a line connecting said tooth flank with said axis, the difference between substantially perpendicular and a right angle lying within the angle of self-locking between the materials used. 
   
   
       10 . The locking device as set forth in  claim 1 , wherein said mass body has a region of large mass located beneath or above said axis in a z-axis direction. 
   
   
       11 . The locking device as set forth in  claim 1 , wherein said at least one retaining inclined portion is inclined at one of an angle of •20°, •10° and at an angle of less than an angle of self-locking of the materials used, with respect to a radial to said axis, said radial intersecting said retaining inclined portion. 
   
   
       12 . The locking device as set forth in  claim 1 , wherein said locking part and said mass body are joined together to form one piece. 
   
   
       13 . A locking device as set forth in  claim 1 , wherein said locking device is a device for an adjustment unit in the form of a hinge mounting. 
   
   
       14 . The locking device as set forth in  claim 1 , wherein said locking part and said mass body are made from one piece.