Patent ID: 7431391

Claim:
An adjustment assembly for securing a bicycle seat, the adjustment assembly comprising: a base adapted to be mounted on top of a seat post and having an arcuate rail formed on two opposed sides of the base and each arcuate rail having two inclined portions formed respectively on two respective edges of each arcuate rail; two adjusting seats oppositely and slidably connected to the base, each adjusting seat having an arcuate track formed on a bottom thereof to correspond to and to receive therein a corresponding one of the arcuate rails of the base, a clamping portion formed on a top portion of each adjusting seat, a through hole defined therethrough and an arcuate cutout defined in an outer face of each adjusting seat, and each arcuate track having two inclined portions formed respectively on two respective edges of each arcuate track to correspond respectively to the inclined portions on a corresponding one of the arcuate rails of the base, wherein the two adjusting seats are movable relative to the base after the two arcuate rails of the base are received in the corresponding arcuate tracks of the adjusting seats and the bicycle seat sandwiched between the two adjusting seats is able to move along with the two adjusting seats relative to the base to accomplish angle change purpose; and a securing element having a bolt, a washer and a nut, wherein the bolt is extended through the washer and the two through holes of the two adjusting seats to be threadingly connected to the nut, and the washer and the nut respectively have an arcuate surface corresponding to the arcuate cutouts of the two adjusting seats are received in and secured inside the arcuate cutouts of the two adjusting seats through the arcuate surfaces, whereby the washer is able to maintain tension between the bolt and the nut.