Buckle apparatus for safety belt

A buckle apparatus for safety belt assembly, comprising:

• a tongue member having notches on opposite side edges;
• a base plate member having a portion of substantially rectangular C-shaped cross section for insertion of the tongue member, and being formed on opposite sides thereof with guide grooves each having supporting surfaces substantially perpendicular to the direction of tongue insertion;
• a pair of tongue latching plate members each having a flat surface and being slidable along the respective guide grooves of the base member in a direction substantially perpendicular to the direction of tongue insertion;
• biasing means for resiliently urging the tongue latching plate members so that the tongue latching plate members may engage the respective notches of the tongue member and be supported at their said flat surfaces by said supporting surfaces of the guide grooves, when the tongue member is inserted into the base member, to latch the tongue member;
• and
• operable means including cam portions for moving the tongue latching plate members against the force of said biasing means in the direction of disengagement from said notches of the tongue member.