【正文】
摘 要:隨著能源日益緊張,人們對(duì)發(fā)動(dòng)機(jī)時(shí)的舒適性日益重視,有關(guān)發(fā)動(dòng)機(jī)冷卻水溫的研究得到了越來(lái)越多科研機(jī)構(gòu)的重視。因?yàn)槔鋮s水溫與發(fā)動(dòng)機(jī)的許多工作性能有著直接或間接的聯(lián)系,如果冷卻水溫保持在最佳的溫度范圍內(nèi),不僅可以提高發(fā)動(dòng)機(jī)的動(dòng)力性、減少?gòu)U氣的產(chǎn)生、還可以減少燃料消耗量、增強(qiáng)發(fā)動(dòng)機(jī)工作平穩(wěn)性。所謂最佳溫度范圍指冷卻水溫保持在此溫度范圍內(nèi),發(fā)動(dòng)機(jī)工作的整體經(jīng)濟(jì)性最好。而確定此最佳冷卻水溫范圍,只有經(jīng)過(guò)大量的檢測(cè)實(shí)驗(yàn)和數(shù)據(jù)分析才能得出。檢測(cè)冷卻水溫對(duì)發(fā)動(dòng)機(jī)零件磨損、功率、工作噪聲、排氣質(zhì)量、潤(rùn)滑油質(zhì)量、使用壽命、工作粗暴性等的具體影響,然后通過(guò)比較分析得出最佳溫度范圍。進(jìn)行這些發(fā)動(dòng)機(jī)性能測(cè)試實(shí)驗(yàn)的必備條件是有一個(gè)能檢測(cè)并控制冷卻水溫在設(shè)定范圍內(nèi)的控制裝置,研究并試制這樣一個(gè)自動(dòng)控制裝置就是本課題的研究目的。本文介紹了一種基于MCS-51系列單片機(jī)的發(fā)動(dòng)機(jī)冷卻水溫自動(dòng)監(jiān)測(cè)系統(tǒng)的設(shè)計(jì),該系統(tǒng)實(shí)現(xiàn)了對(duì)監(jiān)測(cè)到的水溫進(jìn)行及時(shí)采集和智能化處理的功能。簡(jiǎn)述了其工作原理、硬件系統(tǒng)及軟件編程思路。關(guān)鍵詞:冷卻水溫,單片機(jī),A/D轉(zhuǎn)換器、發(fā)動(dòng)機(jī) 、MCS-51Summary:With the increasingly tense energy, people fort when the engine increasing attention, the engine cooling water temperature of gaining more and more attention to scientific research institutions. Because many of the engine cooling water temperature and the performance has a direct or indirect contact, if the cooling water temperature maintained at optimum temperature range, not only can improve the engine39。s power Xing, Jian Shao gas production, also can reduce fuel consumption, Zeng Qiang engine stationary work. The socalled optimal temperature range means cooling water temperature maintained at this temperature range, the overall economy of the engine work the best. And determine the optimal cooling temperature range, only after detection of a large number of experiments and data analysis in order to obtain. Detection of the cooling water temperature on the wear of engine ponents, power, work noise, exhaust quality, oil quality, life, work and so the specific impact of the gross, and then analyzed by paring the optimum temperature range. Engine performance tests for these experiments is a necessary condition to detect and control the cooling water temperature in the range of set of control devices, research and trial of such a control device that is the subject of research purposes. This paper introduces a microputerbased MCS51 series engine cooling water temperature automatic monitoring system, the system realized the water temperature was monitored for timely acquisition and intelligent processing functions. Outlined its working principle, hardware systems and software programming ideas. Key words: cooling water temperature, microcontroller, A / D converter, engine, MCS51引 言發(fā)動(dòng)機(jī)是現(xiàn)在動(dòng)力的主要來(lái)源之一。發(fā)動(dòng)機(jī)工作熱負(fù)荷大, 作業(yè)時(shí)周圍環(huán)境灰塵多,氣溫一般又較高,容易使發(fā)動(dòng)機(jī)水溫升高。必須有良好的散熱條件,因此冷卻系統(tǒng)工作狀態(tài)應(yīng)予以監(jiān)控。冷卻系統(tǒng)工作狀態(tài)的主要參數(shù)是冷卻水溫度。并且發(fā)動(dòng)機(jī)水溫?cái)?shù)據(jù)也是汽車電控系統(tǒng)使用的主要數(shù)據(jù)之一,也是發(fā)動(dòng)機(jī)暖機(jī)情況的主要指標(biāo)。冷卻水溫的過(guò)高過(guò)低都會(huì)對(duì)發(fā)動(dòng)機(jī)的工作狀況造成破壞。本文采用了MCS-51系列單片機(jī)進(jìn)行了發(fā)動(dòng)機(jī)水溫?cái)?shù)據(jù)的自動(dòng)檢測(cè),對(duì)進(jìn)一步提高發(fā)動(dòng)機(jī)的性能發(fā)揮具有重要意義。第一章 單片機(jī)控制系統(tǒng)原理本系統(tǒng)利用溫度傳感器實(shí)現(xiàn)對(duì)溫度的采集,然后把溫度信號(hào)轉(zhuǎn)變?yōu)殡妷耗M信號(hào),信號(hào)通過(guò)運(yùn)算放大器、保持器和A/D轉(zhuǎn)換器將模擬量變?yōu)閿?shù)字量送入單片機(jī)進(jìn)行處理。單片機(jī)根據(jù)不同的輸入信號(hào)分析處理,并將檢測(cè)到的水溫通過(guò)數(shù)字顯示電路顯示出來(lái),進(jìn)而與設(shè)定參數(shù)進(jìn)行比較,如果超出設(shè)定值,立即啟動(dòng)報(bào)警系統(tǒng),告知工作人員采取相應(yīng)的措施;如果正常,循環(huán)采集數(shù)據(jù),即可實(shí)現(xiàn)發(fā)動(dòng)機(jī)水溫的自動(dòng)檢測(cè)。本系統(tǒng)以MCS51單片機(jī)為核心,組成一個(gè)集發(fā)動(dòng)機(jī)水溫的采集、數(shù)據(jù)處理、顯示、報(bào)警為一體的自動(dòng)監(jiān)測(cè)系統(tǒng),其原理見(jiàn)(圖1)。圖中硬件電路主要由以下幾部分組成:?jiǎn)纹瑱C(jī)控制器、顯示系統(tǒng)、水溫監(jiān)控電路、報(bào)警器。(圖1)第二章 系統(tǒng)主要硬件介紹及電路設(shè)計(jì)單片機(jī)單片機(jī)是一種集成在電路芯片,是采用超大規(guī)模集成電路技術(shù)把具有數(shù)據(jù)處理能力的中央處理器CPU隨機(jī)存儲(chǔ)器RAM、只讀存儲(chǔ)器ROM、多種I/O口和中斷系統(tǒng)、定時(shí)器/計(jì)時(shí)器等功能(可能還包括顯示驅(qū)動(dòng)電路、脈寬調(diào)制電路、模擬多路轉(zhuǎn)換器、A/D轉(zhuǎn)換器等電路)集成到一塊硅片上構(gòu)成的一個(gè)小而完善的計(jì)算機(jī)系統(tǒng)。單片機(jī)誕生于20世紀(jì)70年代末,經(jīng)歷了SCM、MCU、SoC三大階段。 (Single Chip Microputer)階段,主要是尋求最佳的單片形態(tài)嵌入式系統(tǒng)的最佳體系結(jié)構(gòu)。(Micro Controller Unit)階段,主要的技術(shù)發(fā)展方向是:不斷擴(kuò)展?jié)M足嵌入式應(yīng)用時(shí),對(duì)象系統(tǒng)要求的各種外圍電路與接口電路,突顯其對(duì)象的智能化控制能力。 ,向MCU階段發(fā)展的重要因素,就是尋求應(yīng)用系統(tǒng)在芯片上的最大化解決;因此,專用單片機(jī)的發(fā)展自然形成了SoC