旋轉式PET吹瓶機的生產效率及穩定性是由其吹瓶模座裝置所決定的，此裝置是由吹瓶模座、凸輪機構、以及吹瓶模座連桿機構所組成；其中，吹瓶模座、開關模座凸輪、以及吹瓶模座連桿機構之組合稱為吹瓶模座凸輪連桿機構。當吹瓶模座裝置進行吹氣成瓶的過程時，此凸輪連桿機構將驅動吹瓶模座產生開模與關模的運動。而開關模座凸輪運動曲線之設計，將影響吹瓶模座的運動特性及吹氣成瓶過程的效率。因此，為了提升旋轉式吹瓶機的性能，本研究針對廠商所提供的旋轉式PET吹瓶機，研究開關模座凸輪運動曲線之設計與輪廓外型之合成。
首先，依據向量迴路法及牛頓力學，對倒置型的吹瓶模座凸輪連桿機構進行運動分析及靜動力分析之數學模式的建立。再根據吹瓶模座作動時之設計需求和限制，以基本凸輪運動曲線(MS, MT, MCV)來設計吹瓶模座的運動，推導出在此三種運動曲線下，吹瓶模座連桿機構的運動與靜動力特性以及凸輪機構的輸入力。然後應用Bezier曲線結合ALM最佳化設計方法設計出適合吹瓶模座運動的凸輪運動曲線，改進連桿機構的運動、靜動力特性、以及凸輪機構所需的輸入力。最後依據包絡理論推導出開關模座凸輪機構的輪廓外型，並分析凸輪機構的壓力角。此Bezier曲線結合最佳化設計方法的凸輪運動曲線，改善了吹瓶模座在吹氣成瓶過程中運動的不連續性，消除吹瓶模座開模與關模瞬間所產生的衝擊力，並降低連桿機構施加在機架上的作用力、開關模凸輪機構的輸入力、以及凸輪的壓力角。
此外，本研究以Visual Basic 6.0軟體，撰寫一套時序設計程式，用來設計吹瓶模座裝置之凸輪機構間的時序，減少凸輪運動曲線之選用與時序修改所耗費的時間。本研究並整合Visual Basic 與OpenGL模擬環境，發展運動模擬程式，模擬吹瓶模座凸輪連桿機構、入胚凸輪連桿機構、及出瓶凸輪連桿機構之間的運動，以驗證本設計的正確性。
本研究利用Bezier曲線結合最佳化設計方法所設計的運動曲線，改善了吹瓶機之吹瓶模座的運動與靜動力特性，消除開模與關模瞬間所產生的衝擊力，降低開關模座凸輪機構的壓力角與輸入力，使合作廠商的吹瓶機生產量由每小時8000瓶提升到每小時11000瓶，總產量提昇37.5%，成功的改善了旋轉式PET吹瓶機之生產效率與穩定性。

The manufacture efficiency and stability of rotary type PET bottle blow-molding machines are determined by the blow-station device. This device consists of blow-stations, cams, and blow-station linkage mechanisms, in which, the combination of the blow-station, the blow-station linkage mechanism, and the open/close blow-station cam mechanism is called the blow-station cam-linkage mechanism. When the blow-forming process of the blow-station device is progressing, the cam-linkage mechanism drives the blow-station to generate open/close motion. The design of motion curve of the cam for open/close blow-station cam affects the kinematic characteristics of the blow-station and the efficiency of the blow-forming process. Hence, in order to improve the performance of the rotary type blow-molding machine, this work targets on the design of the open/close blow-station cam mechanism for a rotary type blow-molding machine provided by a local industry.
First, the vector loop method and Newton’s laws of motion are used to develop the mathematical models for the kinematic analysis and kinetostatic analysis of the inverse blow-station cam-linkage mechanism. Based on the design requirements and constraints of motion of the blow-station, by applying basic cam motion curves (MS, MT, MCV) to design the motion of the blow-station, the kinematic and kinetostatic characteristics of the blow-station linkage mechanism and the input force of the cam mechanism are derived. Then, by using the Bezier curve integrated with ALM optimum design approach, the feasible cam motion curve used to design the motion of the blow-station is obtained. And the kinematic and kinetostatic characteristics of the blow-station linkage mechanism and the input force of the cam mechanism are improved. Finally, according to the theory of envelope and the definition of pressure angle, the profile of the cam mechanism is synthesized and the pressure angle of the cam mechanism is analyzed.
The motion curve of the cam designed by Bezier curve integrated with optimization design approach improves the kinematic discontinuous of the blow-station during the blow-forming process. The impulse force at the interface between the open/close phases of the blow-station is also eliminated. As the result, the joint forces from the blow-station linkage mechanism to the frame, the input force of the open/close blow-station cam mechanism, and the pressure angle are decreased.
Furthermore, a Time Sequence Design Program is developed under the Visual Basic 6.0 software and is used to design the time sequence of the cams of the blow-station device. The Visual Basic software integrated with OpenGL simulation environment is applied to develop the OpenGL Motion Simulation Program. This program simulates the relative motion between the blow-station cam-linkage mechanism, the infeed preform cam-linkage mechanism, and the outlet bottle cam-linkage mechanism. This program is used to verify the motion of the proposed design.
In summary, the motion curve designed by Bezier curve integrated with optimum design approach improves the kinematic and kinetostatic characteristics of the blow-station of the blow-molding machine, eliminates the impulse force at the interface between the open/close phases, and decreases the pressure angle and input force of the open/close blow-station cam mechanism. And, the result of this work successfully decreases the vibration and noise of the blow-molding machine and increases the productivity of the blow-molding machine form 8000 bottle/hour to 11000 bottle/hour, i. e., an improvement of 37.5%.

1.　W. J. Yu, November 3-4, 2003, The Market Prospection of Performs in China (中國瓶胚市場展望), The Fifth Proceedings of the Fifth National Conference of PET Market of China, Shanghai. (In Chinese)
2.　M. T. Chiao, 1998, The Forming and dvelopment of the PET Bottle (PET寶特瓶的成型與發展), The Magazine of Macromolecule Industry, Vol. 78, pp. 60-65, Taiwan. (In Chinese)
3.　Y. H. Gau and C. C. Shih, November 3-4, 2003, The Cold Packing Technique without Germs of the PET Bottles (PET瓶無菌冷罐裝技術), Proceedings of the Fifth National Conference of PET Market of China, Shanghai. (In Chinese)
4.　S. J. Liang, November 3-4, 2003, The Drink Market of Tea in China (中國PET茶飲料市場), Proceedings the Fifth of National Conference of PET Market of China, Shanghai. (In Chinese)
5.　F. A. Juang, January 4, 2005, The Business Opportunities of PET Bottles (PET瓶商機俏), The Newspaper of Industry and Business, Taiwan. (In Chinese)
6.　I. Kauffman and R.C. Kellogg, 1979, Rotary Stretch Blow Molding Apparatus, U.S. Patent No. 4141680.
7.　T. Valles, 1997, Apparatus for Making Containers by Blow Moulding Plastic, U.S. Patent No. 5683729.
8.　H. Winter and K. Griesbeck, 2000, Blow Moulding Machine, U.S. Patent No. 6152723.
9.　J. Choinski, 2002, Method and Device for Blow-Forming Containers, U.S. Patent No. 6770238.
10.　P. Rose, 2002, Process and Device for Controlling the Molding of a Container, U.S. Patent No. US 2002/0011681 A1.
11.　T. Albrecht, 2003, Blow Mold and Blow Molding Machine, U.S. Patent No. US 2003/0138517 A1.
12.　E. H. Hernann, 2004, Blow Mold and Method for Adjusting a Blow Mold, U.S.　Patent No. US 2004/0104517 A1.
13.　Krones, 2000, Method for Rotating Blow-Moulding Preforms in a Star-Shaped Feed Device and a Star-Shaped Feed Device, WO 01/ 76850 A1.
14.　Krones, 2002, Device and Method for Producing Blow-Moulded Containers, WO 02/49829 A1.
15.　H. A. Rothbart, 1956, Cams Design: Dynamics and Accuracy, Wily, New York.
16.　H. Makino, 1976, Mechanisms of Automatic Machines, The Nikkan Kogyo Shinbun Ltd., Tokyo.
17.　R. C. Johnson, 1984, “Force Reduction by Motion Design in Spring-Loaded Cam Mechanisms,” ASME Transactions, Journal of Mechanisms,　Transmissions, and Automation in Design, Vol. 106, pp. 278-284.
18.　D. M. Tasy and C. O. Huey, 1988, "Cam Motion Synthesis Using Spine Functions," ASME Transactions, Journal of Mechanisms, Transmissions, and Automation in Design, Vol. 110, pp.161-165.
19.　B. L. MacCarthy, 1988, “Quintic Splines for Kinematic Design,” Computer-Aided Design, Vol. 20, No. 7, pp. 406–415.
20.　D. M. Tasy and C. O. Huey, 1993, “Application of Rational B-Splines to the Synthesis of Cam Follower Motion Programs,” ASME Transactions, Journal of Mechanical Design, Vol. 115, pp. 621-626.
21.　K. Yoon and S. S. Rao, 1993, “Cam Motion Synthesis Using Cubic Splines,” ASME Transactions, Journal of Mechanical Design, Vol. 115, No. 3, pp. 441–446.
22.　K. L. Ting, N. L. Lee, and G.. H. Brandan, 1994, “Synthesis of Polynomial and Other Curves with the Bezier Technique,” Mechanism and 　　　　Machine Theory, Vol. 29, No. 6, pp. 887–903.
23.　H. S. Yan, and M. K. Fong, 1994, “An Approach for Reducing the Peak Acceleration of Cam-follower Systems using a B-spline Representation,”Journal of the Chinese Society of Mechanical Engineers (Taiwan), Vol. 15, 　　No. 1, pp. 48-55.
24.　D. M. Tsay and B. J. Lin, 1996, “Improving the Geometry Design of Cylindrical Cams using Nonparametric Rational B-splines,” Computer-Aided Design, Vol. 28, No. 1, pp. 5–15.
25.　H. Qiu, C. J. Lin, Z. Y. Li, H. Ozaki, J. Wang, and Y. Yue, 2005, “A Universal Optimal Approach to Cam Curve Design and Its Applications,”Mechanism and Machine Theory, Vol. 40, No. 6, pp. 669-692.
26.　W. B. Carver and B. E. Quinn, 1954, “An Analytical Method of Cam Design,” ASME Mechanical Engineering, Vol. 67, pp. 523-526.
27.　R. C. Johnson, 1955, “Method of Finite Difference Provides Simple But Flexible Arithmetical Techniques for Cam Design,” Machine Design, Vol. 27, pp. 195-204.
28.　R. C. Johnson, 1956, “A Rapid Method for Develop Cam Profiles Having Desired Acceleration Characteristic,” Machine Design, Vol. 27, pp. 129-132.
29.　S. H. Roger, 1962, “New Cam Design Equation,” Product Engineering, Vol. 21, pp. 45-55.
30.　J. Chakraborty and S. G. Dhande, 1975, Kinematics and Geometry of Planar and Spatial Cam Mechanisms, Wily, New York.
31.　J. K. Davidson, 1978, “Calculating Cam Profiles Quickly,” Machine Design, Vol. 50, No. 28, pp. 151-155.
32.　D. M. Tsay and H. M. Wei, 1993, “Profile Determination and Analysis of Cylindrical Cams with Oscillating Roller-followers,” Proceedings of ASME Design Automation Conference, Advances in Design Automation, De-Vol.65-1,　pp. 711-718.
33.　D. C. Tao, 1967, Fundamentals of Applied Kinematics, Wesley, Canada.
34.　F. Y. Chen, 1977, “Survey of the State of the Art of Cam System Dynamics,” Mechanism and Machine Theory, Vol. 12, No. 3, pp. 201-224.
35.　F. Y. Chen, 1982, Mechanics and Design of Cam Mechanisms, Pergamon Press, New York.
36.　G. N. Sandor and A. G. Erdman, 1984, Advanced Mechanism Design: Analysis and Synthesis, Vol. 2, Prentice-Hall, New Jersey.
37.　P. W. Jensen, 1987, Cam Design and Manufacture, 2nd Edition, Marcel Dekker, New York.
38.　H. S. Yan, 1999, Mechanisms (機構學), 2nd Edition, Tung Hua Book Co., Taipei, Taiwan. (In Chinese)
39.　R. L. Norton, 2002, Cam Design and Manufacturing Handbook, Industrial Press Inc., New York.
40.　R. L. Norton, 2004, Design of Machinery, 3rd Edition, McGraw-Hill Co., New York.
41.　A. S. Hall, Jr., 1986, Notes on Mechanism Analysis, Waveland Press, Illinois, USA.
42.　J. H. Chen, 2005, Visual Basic 6 Study Book (Visual Basic 6學習手冊), Jin He Book Co., Taipei, Taiwan. (In Chinese)
43.　R. S. Wright, and J. M. Sweet, 2000, OpenGL SUPERBIBLE (OpenGL超級手冊), 2nd Edition, GOTOP Information Inc., USA. (In Chinese)