Laparoscopic surgical instruments have been used widely since 1980s and they are still important tool to the medical field as the surgical robot systems spread. In this study we devised three types of motorized mechanism to reduce the user hand fatigue. We detailed the mechanism of each type and compared the performances with several indices such as a bending angle, response time and number of mechanical components. And also we show the movement relationships among the jaw joint, passive gimbal set and motors in the case of MPDG (Motor Drive with a Push Disk and Driven Disk of Gimbal Mechanism) type during the typical jaw joint motions. MTPS (Modified Two Parallel Semicircle Guide Mechanism) type excels others in response time and number of components while showing the increase of load and kinematic occlusion during the diagonal movement. MBDG (Motor Drive with a Ball-Screw, Link and Disk Type Gimbal Mechanism) type shows the medium level bending performance with slow response time and large number of components. Lastly MPDG type excels in jaw joint bending performance with an unstable rotation motion transfer between pushing disk and driven disk at the large disk rotation angle.