Mechanism for opening and closing barrier

An automatic gate opening device comprising:

• a gate drive axis, movable between a gate closed position and a gate open position;
• a treadle;
• rechargeable energy storage means;
• energy conversion means to convert stored energy into rotational movement of the drive axis in a gate opening;
• and
• energy conversion means to convert stored energy into rotational movement of the drive axis in a gate closing direction;
• wherein the treadle is configured such that, with the drive axis in its gate open position, a single actuation of said treadle recharges the energy storage means with sufficient energy to move the drive axis from its gate open position to its gate closed position and back to its gate open position wherein.
• the rechargeable energy storage means comprises a pair of springs;
• the energy conversion means to convert stored energy into rotational movement of the drive axis in a gate closing direction comprises a first drive rod connected to a first one of said pair of springs and movable between an extended and a retracted position;
• the energy conversion means to convert stored energy into rotational movement of the drive axis in a gate opening direction comprises a second drive rod connected to a second one of said pair of springs and movable between an extended and a retracted position;
• and
• as the treadle is actuated the drive rods are extended and the associated springs are stretched.