Fastener for document folder

A fastener for a document folder, comprising:

• a base plate,
• a hook bracket and torsion springs,
• wherein a front end of the base plate is extended upwards and curled to form a bending section;
• a slot formed by the bending section;
• rotating shafts on two sides of a front end of the hook bracket respectively arranged at two ends are inside of the slot;
• the torsion springs respectively sleeved on the rotating shafts on two sides of the front end of the hook bracket;
• ends of the torsion springs are fixed on the rotating shafts and other ends of the torsion springs are fixed on the base plate;
• end sections of the rotating shafts bent upwards to form retaining sections;
• clamp holes engaged with the retaining sections and used for opening the fastener formed on a front of the bending section;
• when the hook bracket turned up along with a rotation of the rotating shafts until the retaining sections of the rotating shafts driven to rotate to the clamp holes, top ends of the retaining sections extended out of the clamp holes and the retaining sections clamped with the clamp holes;
• and
• an upper part of the bending section movably connected with a slider used for closing the fastener and capable of sliding along a surface of the bending section.