Effect of contact area to impact noise

Abstract

Drill impact driver is commonly used for the purposes of drilling and screwing. To operate, a large amount of torque needed to be produced. Larger torque will exert bigger working power, thus increasing the efficiency of the performance of the driver. As there are many types of drill impact driver, the one that exerted the highest torque is by using a direct impact mechanism between the anvil and the striker. The combination of the spring and gearing system will provide the highest forward-trust torque. However, this combination of impact mechanism generates the highest noise comparing to other drill impact that only uses either gear system only or the mechanism do not have direct contact and are damped with special fluid. Therefore, a study of relationship between the areas of impact to the sound pressure level is needed to be done in order to achieve the optimum surface area of impact that generates the lowest sound. Microphone 01dBA SOLO Sound Level Meter (SLM) and Dewesoft software are used to capture and analyse the noise data of the drop impact of five aluminium cylinders with different impact area towards its respective sound pressure level.