Connecting rod and double reclining mechanism

Abstract

A connecting rod having satisfactory insertion performance for a mating member and generating neither vibrations nor noises in regard to a connecting rod cut in a predetermined length by searing work and provided with rotation transmitting portions having a non-circular cross section at least at both ends and a double reclining mechanism are provided. A small-diameter column portion 101 having a diameter smaller than a diameter of a rotation transmitting portion T, a tapered portion 103 provided continuously from the small-diameter column portion 101 and gradually increasing in diameter, and the rotation transmitting portion T provided continuously from the tapered portion 103 are provided at least at one end of a connecting rod 13 from a tip-end side.

1 . A connecting rod cut in a predetermined length by shearing work and provided with a rotation transmitting portion having a non-circular cross section at least at each of both ends, characterized in that:
 at least one end is provided with, from a tip-end side,
 a small-diameter column portion having a diameter smaller than a diameter of the rotation transmitting portion, 
 a tapered portion provided continuously from the small-diameter column portion and gradually increasing in diameter, and 
 the rotation transmitting portion provided continuously from the tapered portion. 
   
     
     
         2 . The connecting rod according to  claim 1 , characterized in that:
 the other end is provided with, from a tip-end side,
 a fall-out preventing portion allowed to abut on an opening rim of a hole in which to insert the rotation transmitting portion, 
 a tapered portion provided continuously from the fall-out preventing portion and gradually increasing in diameter with distances from a tip end, and 
 the rotation transmitting portion provided continuously from the tapered portion. 
   
     
     
         3 . A double reclining mechanism provided with reclining mechanisms each tilting a seat back with respect to a seat cushion on both sides of a seat, characterized in that:
 the connecting rod set forth in  claim 1  is used as a connecting rod that transmits an action of one reclining mechanism to the other reclining mechanism.   
     
     
         4 . A double reclining mechanism provided with reclining mechanisms each tilting a seat back with respect to a seat cushion on both sides of a seat, characterized in that:
 the connecting rod set forth in  claim 2  is used as a connecting rod that transmits an action of one reclining mechanism to the other reclining mechanism.