Derailleur apparatus for bicycles

A derailleur apparatus for bicycles, comprising:

• an installation housing, installed on a handle of a bicycle;
• and
• a gearshift control assembly, installed inside the installation housing, comprising:
• a movable first lever, comprising:
• a first pawl, for an up-shift movement with cable-pulling;
• and
• a first lever pivot;
• a ratchet assembly, comprising a ratchet plate, wherein said ratchet plate has up-shifting index teeth and down-shift index teeth, said ratchet plate is disk shaped with a first side and a second side, said up-shifting index teeth is positioned at said first side with a radial direction, and said down-shifting index teeth is positioned at said second side with said radial direction, and said first lever pivot penetrates said ratchet assembly;
• a movable second lever for cable-releasing;
• a return pin;
• and
• an index claw with a second pawl and a matching member;
• wherein said first pawl engages said up-shifting index teeth, and said ratchet assembly rotates toward a first direction to perform an up-shift movement while said first lever is moved in a cable-pulling direction;
• wherein said second pawl engages said down-shifting index teeth, the index claw is connected with said return pin and pivoting around said return pin, and said second lever performs a down-shifting movement by pushing said matching member to pivot said index claw around said return pin and to move said second pawl and having the ratchet assembly to rotate toward a second direction;
• wherein said second lever moves in a clockwise direction and a counter clockwise direction and has two convex portions, said matching member has two concave portions respectively matching said two convex portions, said two convex portions move out of said two concave portions when said second lever moves in said clockwise direction, and said two convex portions move out of said two concave portions when said second lever moves in said counter clockwise direction.