Kinematic Design of a Toggled Mold-Clamping Mechanism for Vertical Injection Molding Machines

• Main Authors: Fu-Chieh Chang, 張富傑
• Other Authors: Chin-Hsing KUO
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/q899vr

碩士 === 國立臺灣科技大學 === 機械工程系 === 103 === Toggled mold-clamping mechanism is an important element for vertical injection molding machine. Currently adopted directly from the mechanism in the horizontal counterpart. However, in order to make the mass center of gravity near the ground and to fix the lower mold on the frame, the driving motor of the toggled mold-clamping mechanism has to be installed on a moving plate. Such an installation will unfortunately ask the motor to bear the weight itself, which induces high power consumption and increases the maximum demanding motor torque to the machine. Therefore, this thesis aims to figure out a new toggled mold-clamping mechanism design, which is suitable for use in vertical injection molding machines. We first reviewed literatures about the toggle mechanism design and used the available structural synthesis method to find an Watt’s six-bar linkage with different link-type assortment to the existing design. Then, we established a mathematical model to formulate the kinematics and inverse dynamics of the mechanism. Accordingly, three optimal dimensional designs of the mechanism were derived including the 1) minimal maximum motor torque, 2) minimal average input power, and 3) minimum of maximum input torque and mean input power subject to the same total weight, molding speed, clamping force and workspace as the existing commercially-available machines. The design results indicated that: 1) Case 1: Under the optimal mechanism dimension in this case, the maximum motor torque is only about 13% of that in the existing machine. And the motor average power is about 44.9% of that in the existing machine. 2) Case 2: Under the optimal mechanism dimension in this case, the maximum motor torque is only about 19% of that in the existing machine. And the motor average power is about 44.6% of that in the existing machine. 3) Case 3: Under the optimal mechanism dimension in this case, the maximum motor torque is only about 16% of that in the existing machine. And the motor average power is about 44.9% of that in the existing machine.