بررسی انتقال پذیری ارتعاش از دسته ارّه موتوری به مچ و بازوی کاربر

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی دکتری/ دانشگاه تبریز

2 استاد/ دانشگاه تهران

چکیده

ارتعاشات دست- بازو می‌توانند سبب بروز اختلالات اسکلتی، عضلانی و عروقی گردند. ارّه موتوری کاربر خود را تحت تأثیر ارتعاشات شدید دست- بازو قرار می‌دهد. در این مطالعه انتقال‌پذیری ارتعاشات از دسته ارّه موتوری به مچ دست و بازوی کاربر بررسی شده است. سیگنال‌های شتاب ارتعاش در حین کار با ارّه موتوری Stihl- MS230 در سه دور آرام، نامی و تند، سه موقعیت دسته جلو ارّه، مچ و بازوی کاربر و در سه جهت عمودی، جانبی و محوری در پنج تکرار بررسی شد. نتایج نشان داد که اثرات اصلی جهت و دور موتور و نیز اثر متقابل آن‌ها بر مقادیر ریشه میانگین مربعات شتاب ارتعاش در هر سه موقعیت، در سطح 1% معنی‌دار هستند. همچنین ارتعاشات در حین انتقال از دسته به مچ و بازوی کاربر توسط اعضای بدن میرا می‌شوند. میرایی در فرکانس‌های بالاتر بهتر صورت می‌گیرد. کمترین میزان میرایی، در دور آرام موتور اتفاق افتاد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigation of vibration transmissibility from chainsaw handle to wrist and arm of operator

نویسندگان [English]

  • masoud feyzi 1
  • Ali Jafari 2
  • Hojjat Ahmadi 2
چکیده [English]

Hand-arm vibration can cause vascular, neurological and musculoskeletal disorders, collectively named as hand-arm vibration syndrome. The chainsaw is a portable machine that exposes own operators to high levels of hand-arm vibrations. This research focuses on vibration transmissibility from chainsaw handle to wrist and arm of operator. The vibration acceleration signals necessary for evaluation were obtained in an experiment using a Stihl-MS230 chainsaw in three positions (the front handle of chain saw, the wrist and arm of operator), in lateral, longitudinal, and vertical directions. Tests were performed at three levels of engine speed (2800, 10000, and 13300 RPM). The results indicated that the effects of speed, axis, and the interaction between them on the RMS were significant at 1% level. The vibrations were damped during transfer process from handle to hand and arm by organs of operator body. Vibrations in high speeds were damped better than those for low speeds. The maximum value of vibration transmissibility from handle to wrist occurred in engine speed of 2800 RPM.

کلیدواژه‌ها [English]

  • "Chainsaw"
  • "Hand- arm vibration"
  • "1/3 octave bands"
  • "Root mean square"
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