Effort-saving stapler

An effort-saving stapler comprising:

• a shell device consisting of two halves and a front shell, wherein each half forms a track groove;
• a magazine disposed in the halves for supporting and feeding staples;
• a hammer disposed in the halves for hammering the staples, one at a time;
• a power spring disposed in the shell for biasing the hammer;
• a block disposed in the halves, wherein the block comprises teeth formed thereon;
• a triggering device including a trigger pivotally connects to the shell device, an operation element and two bearings respectively installed to the track grooves slideably,
• wherein the trigger includes two walls formed on an end thereof and spaced from each other, a first pivot hole formed each wall, and teeth formed on one of the walls and engaging with the teeth of the block;
• wherein the operation element is disposed in the space and includes a track groove and a driving portion inserting in the hammer;
• and
• a pivot pin inserted through the first pivot holes and the track groove to the bearings;
• wherein the pivot pin is driven to move relative to the trigger and drives the operation element via pressing the trigger downwardly so that when the trigger is operated, the hammer is lifted by the operation element and the pivot pin is moved towards the hammer.