Patent ID: 8770078

Claim:
A sheet hole punching device for punching holes in a sheet, comprising: a plurality of punching members; a device frame supporting the plurality of punching members thereon linearly to vertically and slidably move the punching members in a hole punching direction; a driving rotation shaft disposed in a direction crossing with the punching members; a drive motor reciprocally rotating the driving rotation shaft within a predetermined angular range; a gear mechanism attached to the driving rotation shaft for transmitting a rotation of the driving rotation shaft as a rotational movement to the punching members; cam mechanisms attached to the punching members for converting the rotational movement of each of the punching members into a vertical movement in the punching direction at a same time of the rotation; and a motor control device to control the drive motor, wherein the gear mechanism includes drive gears fixed on the driving rotation shaft, and receiving gears engaging the drive gears to transmit a rotational movement to the punching members, and each of the cam mechanisms includes a cylindrical cam formed integrally to the punching member and having a V-shaped groove, and a cam follower fixed to the device frame and engaging the V-shaped groove, the cam mechanism reciprocating each of the punching members between an upper dead point and a lower dead point with respect to rotation thereof within a predetermined angular range.