Low-noise power stapler

A power stapler comprising a base, a magazine mounted on said base to carry staples, a follow spring mounted in said magazine to push staples forwards, a spring-supported striking plate controlled to drive staples into sheet of paper, a contact switch, an electromagnetic valve controlled by said contact switch to drive said striking plate, a guard plate adapted for stopping staples in said magazine, an anvil assembly mounted in a hole in said base on which staples are hammered and deformed, and an anvil elevation adjusting device adapted for adjusting the elevation of said anvil assembly, wherein said electromagnetic valve is mounted on two upright frames above said base, comprising a valve rod vertically disposed at the top, a movable annular metal block disposed at the bottom, and a plunger having a top end fixedly connected to said valve rod and a bottom end inserted through said movable annular metal block and stopped above said spring-supported striking plate, said movable annular metal block being energized to attract said valve rod when said electromagnetic valve is turned on, causing said valve rod to force said plunger downwardly against said spring-supported striking plate, said movable annular metal block being simultaneously moved downwards with said valve rod when said valve rod is attracted by said movable annular metal block.