نوع مقاله: مقاله علمی- پژوهشی

نویسنده

دانشگاه آزاد اسلامی- واحد خوراسگان (اصفهان)

چکیده

اثر تجمعی ارتعاشات انتقالی به راننده تراکتور کشاورزی نه تنها سلامتی راننده را تهدید می‎کند بلکه می‎تواند به کاهش بازده کاری وی بیانجامد. یکی از روشهای کاهش سطح ارتعاشات انتقالی به راننده، استفاده از سیستم تعلیق است. در این پژوهش طراحی و ارزیابی مدل تعلیق نیمه فعال کابین تراکتور مورد توجه قرار گرفته است، بنابراین ابتدا مدل ارتعاشی کامل تراکتور توسعه یافت و سپس به طراحی گام به گام مدل میراکن نیمه فعال پرداخته شد. آزمون مدل مشخص کرد که از بین پارمترهای مورد نظر، سطح مقطع پیستون و حجم محفظه هوایی انباره هیدرولیکی روی فرکانس تشدید ارتعاشات انتقالی به راننده تاثیر بیشتری داشت، درحالیکه سطح مقطع پیستون و فشار هوای اولیه انباره، روی مقدار RMS شتاب ارتعاشات انتقالی به راننده تاثیرگذار بود. بعلاوه مقایسه عددی خروجی مدل در حالت استفاده و عدم استفاده از تعلیق نیمه فعال کابین تراکتور در شرایطی که تحت تاثیر تابع تحریک کننده مشابه قرار داشتند، به بهبود قابل ملاحظه RMS شتاب ارتعاشی انتقالی به صندلی راننده تراکتور منجر شد، بنابراین سامانه تعلیق توسعه یافته در این پژوهش قادر به کاستن از سطح ارتعاشات انتقالی به راننده تراکتور می‎باشد.

کلیدواژه‌ها

عنوان مقاله [English]

Design and Performance Assessment of a Semi-Active Suspension Model of Tractor Cabin

نویسنده [English]

  • I Ahmadi

Islamic Azad University, Isfahan

چکیده [English]

Cumulative effect of transmitted vibrations to the tractor driver not only leads to driver health problems, but also reduces the driver working efficiency. Tractor suspension system is one of the methods which is employed to lower the level of transmitted vibrations to the driver. In this study the design and performance assessment of a semi-active suspension model of tractor cabin was considered. Tractor full vibration model was developed first, and subsequently a semi-active ON-OFF damper model was designed. The examination of the model indicated that doubling the piston area and the volume of hydraulic accumulator air chamber, led to 39% increase and 31% reduction of the resonance frequency of transmitted vibrations to the driver, respectively. On the other hand doubling the piston area and the primary air pressure of the accumulator, affected the RMS of transmitted vibration to the driver by 77 cm s-2 reduction and 66 cm s-2 increase, respectively. Moreover, the numerical comparison of the model outputs with and without activation of semi-active cabin suspension, while the model was stimulated with the same input function, led to 43% improvement in RMS acceleration of the transmitted vibrations to the tractor seat. Therefore, the designed semi-active suspension model of cabin was able to attenuate the level of transmitted vibrations to the tractor driver.

کلیدواژه‌ها [English]

  • Agricultural tractor
  • Modeling
  • Semi-active suspension
  • Tractor cabin

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