本論文主要是研究噴墨式印表機之噪音改善技術，針對印表機在各項作動時瞬間所產生的衝擊噪音，採用短時傅利葉轉換來做分析，並發展出一個降低印表機噪音的分析流程。

過程中利用短時傅利葉分析(STFT)的方法，探討印表機在列印時各部份機構作動瞬間產生的衝擊噪音加以分析，並在拆解印表機的過程當中，更能清楚了解印表機的工作方式，並針對其產生噪音的成因，提出方法加以改善，以供在未來產品開發階段，可建立一套完整的噪音測試與設計準則，得以有效改善印表機在運作時的噪音問題。

本實驗針對進紙機構、出紙機構以及除墨匣機構進行分析，並於改善後進紙機構瞬間聲壓約降了3~5 dB(A)；出紙機構約降了4~7 dB(A)；除墨匣機構約降了8~10 dB(A)，並依據實驗之結果，規劃出一個降低噴墨式印表機噪音之設計準則，作為日後開發低噪音產品之參考。

The purpose of this study is to solve the noise problem of inkjet printer caused by impacts between various parts during printing operation. Short-term Fourier Transformation (STFT) was used for analyzing non-steady state noise of the inkjet printer in different printing stages.

Through the process of disassembling the inkjet printer, we can better familiarize ourselves with the motion and interaction between different printer parts. Therefore, the causes of noise generation can be detected and improvements can be proposed to reduce the noise of the printer in the early product development stages.

In this study, we analyzed the motions of the paper feeder, the mechanisms of paper exiting and the ink-removal cartridge in order to understand the noise generation mechanisms. A noise reduction of 3~5 dB(A) was obtained from the paper feeder, a 4~7 dB(A) reduction from the paper exiting mechanism and a 8~10 dB(A) reduction from the ink-removal cartridge mechanism. Based on the experimental results, some low-noise design guidelines were developed for the inkjet printer.

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