Injection Molded Microcellular Plastic Gear (II) - Characteristics of the Counter Pressurized Microcellular Plastic Gear -

초미세발포 플라스틱 기어에 관한 연구 (II) - 카운터프레셔 초미세발포 플라스틱 기어의 특성 -

  • 하영욱 (한양대학교 기계설계학과) ;
  • ;
  • 정태형 (한양대학교 기계공학과)
  • Published : 2005.05.01


This paper investigates the improvement of accuracy and fatigue life of the developed counter pressurized microcellular gears of polyacetal. It is shown that the fatigue life and operational characteristics of the counter pressurized microcellular gears are more improved than conventional injection molded plastic gears by the dynamic gear durability test. For the cases of test sea.5. conventional injection molded sea.5(SGea.) and counter pressurized microcellular gears(CGear) are manufactured. Durability test is performed on both conventional lnjection molded gears and counter pressurized microcellular gears. Accuracy variation and operational characteristics on fatigue life, wear and tooth surface temperature of CGear and Scear are compared and represented. Operational characteristics of the proposed counter pressurized microcellular gears show a good result in this research. The durability limit of counter pressurized microcellular gears is also obtained, and represented by a function of unit load as well as by a function off-factor.


Gear;Microcellular Plastic Gear;Counter Pressure;Durability Test;Gear Accuracy;Fatigue Life;Wear;Unit Load;K-Factor


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