Extending and retracting device for vehicle step

An extending and retracting device for a vehicle step comprising:

• a mounting bracket adapted to be fixed to a body of a vehicle;
• a step bracket;
• an arc sliding member made in the form of an arc sliding block and defining a pair of ends thereof, an intermediate portion of said arc sliding member fixed in said step bracket;
• a driving arm defining a pair of ends thereof pivotally connected to respective said mounting bracket and step bracket;
• and
• a supporting arm defining an upper end portion pivotally connected to said mounting bracket, and a lower end portion, said lower end portion formed with a substantially U-shaped groove defining a pair of side walls thereof, a portion of said step bracket located in said groove, a pair of arc slots are formed in respective said pair of side walls of said groove, said pair of ends of said arc sliding member extending substantially transversely into respective said pair of arc slots;
• and
• wherein said arc sliding member is adapted to fit into said pair of arc slots so as to be slidable in said arc slots such that said lower end portion of said supporting arm is slidably connected to said step bracket.