Patent ID: 7121440

Claim:
A stapler comprising a driver unit having a driver for punching out a staple toward sheets, said driver comprising a drive-out mechanism to drive out the staple when the driver is reciprocated, and the drive-out mechanism comprising a first driving shaft, a clincher unit having a clincher base comprising a clincher to clinch leg portion of the staple passing through the sheets, the driver unit being vertically separated from the clincher unit, said clincher comprising a clincher mechanism for clinching the leg portions of the staple passing through the sheets, said clincher mechanism comprising a second driving shaft, wherein the clincher base is disposed so as to vertically reciprocate, and the sheets are clamped between the clincher base and the driver unit when the clincher base is driven for reciprocation, the stapler further comprising a first driving motor provided for the driver unit to operate the driver, said first driving motor being configured to make the first driving shaft perform one reciprocating movement of the driver when the first driving shaft is rotated by one turn, a second driving motor provided for the clincher unit to reciprocate the clincher base and to operate the clincher, said second driving motor being configured to make the second driving shaft perform one reciprocating movement of the driver when the second driving shaft is rotated by one turn, a first detector for outputting a pulse every time when the first driving shaft turns by a given angle, a second detector for outputting a pulse every time when the second driving shaft turns by a given angle, and a controller for controlling the first and second driving motors based on the number of pulses outputted from the first and second detectors, respectively, wherein the second driving motor is driven to make the clincher base clamp the sheets between the driver unit, and then the second driving motor is stopped; thereafter the first driving motor is driven to make the drive-out mechanism operate toward and drive out the staple through the sheets, and then the first driving motor is stopped; thereafter the second driving motor is driven to make the clincher mechanism operate and clinch the leg portions of the staple having passed the sheets, the clincher base is returned, and then the second driving motor is stopped; and after the clinching operation is terminated, the first driving motor is driven to return the driver to an initial position, and then the first driving motor is stopped.