榔頭振動特性對使用影響之分析

Abstract

消費者在選購榔頭時，以外形、手握感覺及價錢等為購買的考量因素；然而榔頭是作業用的手工具敲擊時整體的感覺才是決定榔頭好壞的關鍵，因在購買時無法即刻體會，因此常被忽略。本研究以此為動機，進行榔頭操作之探討。 振動議題在聲學、環境學、機械力學等被廣泛的探討與應用，在榔頭作業中，以手部所感知的衝擊力及細振感為研究對象，進行受測者敲擊實驗，用以收集榔頭振動特性與操作之主觀偏好，經由迴歸分析中可得知，主觀舒適度、振動特性及設計特徵等對應關係，並將其歸納如下： 1.阻尼指數影響主觀舒適度，阻尼指數越高振動越小，舒適度較高。 2.輕巧短小之榔頭與拔釘彎曲之榔頭其主觀舒適度較高。 3.重量重與長度長之平均能量高，且榔頭振動會越嚴重。

The major considerations on buying a DIY hammer by consumers are the form of a hammer, feelings of the handle, and price. However, the key factor to determine a suitable hammer for DIY users is the degree of uncomfortable feeling caused by vibration while using hammers. Because of the lack of chance for consumers to actually test hammers in a real purchase circumstance, the feeling of vibration on using a hammer has always been neglected. Due to this reason, this research attempted to investigate the feeling of vibration while using hammers. The issue of vibration o has been wildly discussed from in various fields, such as acoustics, environment technology, and dynamics, from different aspects. In this study, 18 hammers with different design features were operated to hit nails by 30 subjects. From this hitting experiment, both data of vibration characteristics generated from the 18 hammers and of the subjective vibration feeling of the 30 subjects to the 18 hammers were gather. Then, by using regression analysis, the corresponding relationships among the design features of hammers, the physical characteristics of vibration and the subjective evaluations on vibration were clarified. The design guidelines for comfortable hammers then were proposed, accordingly, at the end of this research. The main results found in this research included: 1.The damping exponent coefficient of a vibration will influence the users’ subjective feeling on it; the higher the damping exponent coefficient a vibration has, the lighter the vibration and less uncomfortable will be felt. 2.A lighter and smaller hammer with curved claw will be more satisfied in subjective feeling on vibration and comfort. 3.On contrary, a heavier and longer hammer will cause vibration, with higher magnitude, to be significantly felt.