黑龍江科技學(xué)院畢業(yè)設(shè)計(jì)（）姓名： 任務(wù)下達(dá)日期： 年 月 設(shè)計(jì)（論文）開始日期： 年月設(shè)計(jì)（論文）完畢日期： 年月—、設(shè)計(jì)（）DZ60振動(dòng)打樁錘的設(shè)計(jì)二、設(shè)計(jì)的目的和意義：DZ系列振動(dòng)樁錘是吸取了國內(nèi)外先進(jìn)經(jīng)驗(yàn)后設(shè)計(jì)的，重要用于有動(dòng)力電源的多個(gè)建筑工地和港口、地下鐵道、橋梁、高層建筑等樁基礎(chǔ)施工工程。與樁架配套后，可沉混凝土灌注樁、混凝土擴(kuò)底樁、石灰樁、砂樁、碎石樁；配上夾樁器后，可沉拔混凝土預(yù)制樁和各類鋼樁。它是公路、橋梁、建筑等基礎(chǔ)施工的抱負(fù)設(shè)備 三、設(shè)計(jì)（）（1）根據(jù)給定的參考數(shù)據(jù)設(shè)計(jì)計(jì)算振動(dòng)樁錘原動(dòng)機(jī)、激振器和減震器中重要零件的參數(shù)和性能，（2）振動(dòng)打樁錘的總裝圖和重要零件（激振器箱體、傳動(dòng)軸和齒輪等）零件工作圖。（3）設(shè)計(jì)闡明書附加專項(xiàng)論文和英文翻譯及其英語原文 四、設(shè)計(jì)目的：設(shè)計(jì)DZ60振動(dòng)打樁錘，設(shè)計(jì)計(jì)算振動(dòng)樁錘的重要技術(shù)參數(shù)并對(duì)重要零件進(jìn)行強(qiáng)度校核，同時(shí)考慮材料的抗振性能。繪制裝配圖和重要零件圖 五、進(jìn)度計(jì)劃：2007313331行為期3周的生產(chǎn)實(shí)習(xí)；41410日完畢對(duì)設(shè)計(jì)題目的資料收集與查詢；411610日完畢對(duì)設(shè)計(jì)圖紙的繪制；511610畢畢業(yè)設(shè)計(jì)闡明書的編寫；611625后的審稿及闡明書和圖紙的打印 七、參考文獻(xiàn)資料：機(jī)械設(shè)計(jì)手冊(cè).第53機(jī)械工業(yè)出版社，；機(jī)械設(shè)計(jì)手冊(cè).第53機(jī)械工業(yè)出版社，；機(jī)械設(shè)計(jì)手冊(cè).第2卷.第四版.化學(xué)工業(yè)出版社，；機(jī)械設(shè)計(jì)手冊(cè).第3卷.第四版.化學(xué)工業(yè)出版社 彈簧手冊(cè).機(jī)械工業(yè)出版社1997 師： 院（系）主管領(lǐng)導(dǎo)： 年 月 用、故障少、構(gòu)造緊湊、低噪音、高效率、無污染等優(yōu)點(diǎn)。核心詞：翻譯）和CAD圖紙。下載后請(qǐng)聯(lián)系QQ：。我能夠?qū)嚎s冊(cè)賬號(hào)時(shí)最佳用你的QQ號(hào)，以方便我將壓縮包發(fā)給你）tointhevibrationusemachinerytheplanedoubleshafttypedriver.Thevibrationhammerusesfrictiontoreducetheforcebetweenthemechanicalpressurefunctionissuesthegoalofstakesinking.Thevibrationhammerdividesthemechanicaltypeandthehydraulicpressuretypetwokinds,thehydraulicpressurevibrationhammerapplicationareless.Thevibrationhammerusesthemechanicaltypedirectiondetectiondriver.Itisloadedwithsamelackoforcounteractoneanotherinthehorizontalsideupwardforcecomponent,butinverticaldirectionforcecomponentsuperimposition.Thevibrationhammermainlybytheelectricmotor,theguiderod,thecompressionspring,horizontalbeamHasthepenetratingpowerstrongly,thequalityofstakesinkingisgood,firmdurable,thebreakdownfew,thestructureiscompact,thelownoise,thehighefficiency,doesnothavemeritandsoonpollution.Keywords:Vibratesthe Vibratorypiletheinertial thespringreducing TOC\o"1-4"\h\z\u摘 第1章緒 第2 振動(dòng)機(jī)械的用途、分類、工作原理及構(gòu) 振動(dòng)機(jī)械的用途和分 振動(dòng)機(jī)械的構(gòu) 振動(dòng)機(jī)械的用 振動(dòng)機(jī)械的分 慣性振動(dòng)機(jī)械的工作原理與構(gòu) 慣性激振器的形 線性或近似線性的近共振類慣性機(jī) 非線性慣性振動(dòng)機(jī) 沖擊式慣性振動(dòng)機(jī) 樁工機(jī)械的分類和工程應(yīng) 樁工機(jī)械的分 樁工機(jī)械在工程技術(shù)中的應(yīng) 振動(dòng)樁錘的工作原理和構(gòu) 振動(dòng)樁錘的工作原 振動(dòng)樁錘的構(gòu) 沉樁原 第3章電機(jī)的選擇和計(jì) 選擇電動(dòng)機(jī)應(yīng)綜合考慮的問 選擇電動(dòng) 第4章振動(dòng)樁錘的主參數(shù)計(jì) 激振力的計(jì) 計(jì)算實(shí)際振 根據(jù)提供的頻率選擇工作土壤的類 振幅A的擬 計(jì)算實(shí)際偏心力 功率的計(jì) 第5章減振彈簧的設(shè)計(jì)與計(jì) 減振彈簧的構(gòu)造選 選用螺旋彈簧的類型代 選用彈簧的材料并擬定其重要性能參 圓柱螺旋彈簧的設(shè)計(jì)計(jì) 擬定單根彈簧的最大工作載 選擇旋繞 計(jì)算鋼絲直 計(jì)算彈簧中 計(jì)算彈簧圈 計(jì)算實(shí)驗(yàn)載 自由高 彈簧的節(jié) 彈簧的螺旋 彈簧的穩(wěn)定性驗(yàn) 彈簧的強(qiáng)度驗(yàn) 共振驗(yàn) 第6章V帶傳動(dòng)的設(shè)計(jì)計(jì) V帶的計(jì) V帶輪材料和尺寸的擬 第7章經(jīng)濟(jì)分析與資源分 結(jié) 參考文 專項(xiàng)論 致 附錄1中文譯 附錄2英文原 1第2 振動(dòng)機(jī)械的用途、分類、工作原理及構(gòu)30（簡稱振動(dòng)機(jī)械）得到1a彈性元件（彈簧涉及隔振彈簧（2-1按驅(qū)動(dòng)裝置（激振器）慣性式振動(dòng)機(jī)（2-1b圖2-1 1—激振 2—工作機(jī) 3—彈性元4—偏心 5—主 6—軸承和軸承2-22-2 b2-3單軸式圓盤偏心塊r（N，r=e2-1 器器 2cX2-4X

2-2d 振動(dòng)光飾機(jī)振動(dòng)光飾機(jī)慣用來去除機(jī)械加工件、沖壓件和鍛鑄件的毛刺和2-2；⑦風(fēng)動(dòng)式 振動(dòng)料 建筑材料的破碎。例如，在金屬和鋼鐵碎片的持續(xù)再解決廠，每小時(shí)可破碎200μm的粉50-70kg。用慣性破碎機(jī)粉碎造紙用的纖維半制品，比用傳統(tǒng)的盤式墨跡效果好得多。振動(dòng)壓路機(jī)振動(dòng)壓路機(jī)與早期使用的依靠靜壓的壓路機(jī)相比，用于宰割做振動(dòng)成型機(jī)(振動(dòng)臺(tái))這種振動(dòng)機(jī)是鋼筋混凝土構(gòu)件廠的重要成型機(jī)械，用振動(dòng)篩振動(dòng)樁機(jī)用于振動(dòng)沉拔樁的振動(dòng)樁機(jī)如圖2-5雙激振器振動(dòng)圓錐破碎機(jī)這種破碎機(jī)較之單軸式振動(dòng)圓錐破碎機(jī)，能獲得振動(dòng)烘干機(jī)垂直振動(dòng)輸送機(jī)振動(dòng)輸送機(jī)慣用于物料的冷卻與輸送，每臺(tái)機(jī)器的最大輸6-8m20t／h。ωω振動(dòng)機(jī)械主振系統(tǒng)的頻率比為z0 普通為0.75～1.3（慣用的為0.75～0.95，ω0ωω即機(jī)器在近共振狀況下工作。單隔振系統(tǒng)的頻率比z0 普通仍按遠(yuǎn)超共振的狀態(tài)進(jìn)ω01/2～1/8，因而其傳動(dòng)部機(jī)構(gòu)緊湊，尺寸小并且耐用。近共振振動(dòng)機(jī)械工作點(diǎn)（頻率比）2-51—底 2—立 3—斜4—雙軸激振 5）頂部滑輪（如搖床選礦）2-3壓路、振搗、沉拔樁等。DZ2-3類型式 機(jī)機(jī)機(jī)樁工似500mm2-61—原動(dòng) 2—減振 3—激振原動(dòng)機(jī)振動(dòng)樁錘普通采用異步電動(dòng)機(jī)，但規(guī)定電動(dòng)機(jī)能在強(qiáng)烈的振動(dòng)狀態(tài)下可 減振

，Z

式 r—偏心塊的偏心距nnM—激振體的質(zhì)量（kg）m—偏心塊的總質(zhì)量圖2- 振動(dòng)體Z（Z332、根據(jù)負(fù)載轉(zhuǎn)矩、速度變化范疇和啟動(dòng)頻繁度等規(guī)定，考慮電動(dòng)機(jī)的溫升限制、過0.8～0.9。4根據(jù)參考文獻(xiàn)[7]16-1-5、16-1-6、16-1-8、16-1-20IP44。IC0141，B3-13-1 1500rYH280S- r1395r7功率因數(shù)轉(zhuǎn)動(dòng)慣量D955N9551D 式 D—N— nN—額定轉(zhuǎn) nN0—實(shí)際功 400式 —偏心塊的偏心距不不大于樁與土之間的摩擦阻力。根據(jù)給定的參考參數(shù)，當(dāng)φ=90Fm00

m0r=15.54kg·m又2m0

(=A=

M=3250kgA4-1最佳頻率A＝9.5mm，

（4- （υ

，Zω式 nω—激振體的自振圓頻率（s1）M—激振體的質(zhì)量（kg）nm0rβ—阻尼系數(shù)（kgsZ＞3，Z=4，n=7.5πs1n一種質(zhì)量、n（n=8）n=

N 2ωβ=86059.5kg因 υ

將以上計(jì)算所得數(shù)據(jù)代入公式（4-1）00mr=15.54kg·m，g9.8ms200

P

（4-r3P

（4-

（4-式 （kg，φ—相位角（，即振幅滯后于激振力的角度將各參數(shù)數(shù)值代入公式（4-4）相位角φ=16.6。1=35.49kW2

d式 k—考慮其它機(jī)械損耗的系數(shù)，kdd2=4.48kW然后把1和2的數(shù)值代入公式（4-2）可

P=39.97kW5N根據(jù)參考文獻(xiàn)［4］11-2-1Y平，支承圈數(shù)

1

5B［τ］參考文獻(xiàn)［5］8-10［τ］＝（0.35～0.4）σb。材料，再由文獻(xiàn)［5］2-103得切變模量G＝788103P。取實(shí)驗(yàn)切應(yīng)力 ]最大工作載荷ax：對(duì)上彈簧取最大加壓

ax上

4ax

4

根據(jù)文獻(xiàn)［5］C＝5，

131C

d1.

上 上下 33.5mm下5-1

D上彈簧中徑下彈簧中徑＝175mm參考表5-2選用系列值，＝150mm，＝170mm 根據(jù)文獻(xiàn)［5］中表8-13中式K

上彈簧圈數(shù)＝10.5下彈簧圈數(shù)＝13.41得表5-2D12345678925-3n（圈23456789

YⅠt

n

對(duì)上彈簧，有形變量f＝133mm，節(jié)距t對(duì)下彈簧，有形變量f＝167mm，節(jié)距t5-4壓縮彈簧自由高度尺寸系列456789

nt＝48mm，t＝52mmα下上α下上

＝5.5°b=D900r/min

式 τ

＝

f=1

WfW WW＝30kN，則有f＝1.37Hz〈fTW＝37.5kN，則有f＝1.22Hz<fT6VV6-1Vv<20m/s，HT150。鍛造帶輪不允許有砂眼、裂紋、縮孔及氣泡。參考文獻(xiàn)［4］13-1-105-1（mm）：

1o， δδ圖6- 帶輪的輪齒構(gòu)6-1V設(shè)計(jì)功率文獻(xiàn)［4］13-1-取KAP獻(xiàn)［］13-1-選用基準(zhǔn)寬度制窄SPBn1—小帶輪轉(zhuǎn)速，n1=1116r/min)n2i=n1 小帶輪基準(zhǔn)直徑查文獻(xiàn)［］13-1-1013-1-件允許時(shí)dd1取dd1大帶輪基準(zhǔn)直徑1由文獻(xiàn)［4］13-1-11（續(xù)表 60 ν20msν5m/s距a0（1a0（1）選用a0 （d-d2L=2a+（d+d+d2d1d002d1d2 0LdLda 90°取P1＝10.04特定條件 Vz= =5.8V（續(xù)表力F0N α［4］13-1-23mN 倍7經(jīng)濟(jì)性是機(jī)械產(chǎn)品的重要指標(biāo)之一，從產(chǎn)品設(shè)計(jì)到產(chǎn)品制造，應(yīng)始終貫徹經(jīng)濟(jì)性原則，設(shè)計(jì)中在滿足零件使用需求的前提下，從下列幾個(gè)方面來重要體現(xiàn)了本設(shè)計(jì)的經(jīng)濟(jì)性：振動(dòng)樁錘是建筑施工中用來完畢基礎(chǔ)的扎實(shí)和沉、拔樁等工程任務(wù)的重要裝置，它需要提供較大的激振力和比較高的振動(dòng)頻率。因此樁錘的重要構(gòu)成零、部件都需要抗振能力比較強(qiáng)。從材料選擇方面來看，本設(shè)計(jì)經(jīng)濟(jì)性重要體現(xiàn)在激振器箱體、減振彈簧、傳動(dòng)軸和齒輪的材料的選擇上。由于需要抗振能力號(hào)的零件，因此這些零件的材料的選擇在滿足使用條件的前提下，都要考慮材料的抗振性能，從這方面來看，產(chǎn)品的造價(jià)會(huì)有所提高。但是，從使用方面考慮，材料的抗振性能優(yōu)秀能夠減少零件的損耗率，減少零件的更換頻率，因此該振動(dòng)樁錘在生產(chǎn)時(shí)應(yīng)選擇抗振性能好的零件材料。DZ灌注樁、混凝土擴(kuò)底樁（大蒜頭樁、石灰樁、砂樁、碎石樁；配上夾樁器后，可沉拔混凝土預(yù)制樁和各類鋼樁。它是公路、橋梁、機(jī)場、建筑等基礎(chǔ)施工的抱負(fù)設(shè)備。DZ60531323張英會(huì)，劉輝航，王德成主編.彈簧手冊(cè).機(jī)械工業(yè)出版社成大先主編.機(jī)械設(shè)計(jì)手冊(cè).單行本.機(jī)械制圖·成大先主編.機(jī)械設(shè)計(jì)手冊(cè).單行本.減（變）速器·（二）.機(jī)械工7王煥庭，徐善國主編.機(jī)械工程材料.第三版.大連理工大學(xué)出版社1當(dāng)代集成制造系統(tǒng)（ContemporaryIntegratedManufacturingSystem）是計(jì)算機(jī)集2先進(jìn)制造技術(shù)（AMT－AdvancedManufacturingTechnology）作為一種專有名詞至今從按照功效劃分部門的固定組織形式向動(dòng)態(tài)的自主管理的小組工作方式轉(zhuǎn)變。并行工程（CE－Concurrent與并行工程有關(guān)的技術(shù)實(shí)用化不夠：在實(shí)用技術(shù)研究方面，現(xiàn)在還沒有商品化軟件誕生，而國外公司已經(jīng)推出商品化軟件（PTCPro-Engineering、CVCADDS5不好，CAD/CAM虛擬制造（VM－VirtualMatsushitaCoventrySchoolofArtandDesignLabviewCOpenGLOPTRISESRD3D思想并可能實(shí)現(xiàn)的是由上海同濟(jì)大學(xué)張曙專家提出的分散網(wǎng)絡(luò)化生產(chǎn)系統(tǒng)和西安交通大學(xué)謝友柏院士組建的異地網(wǎng)絡(luò)化研究中心。敏捷制造（AM－Agile199150％，生產(chǎn)率提高明顯?，F(xiàn)在美國的諸多大公司都參加了這一研究計(jì)劃，在1993綠色制造（GM－Green3CAD，在技術(shù)的先進(jìn)性方面，不要過分追求世界領(lǐng)先，應(yīng)當(dāng)根據(jù)公司實(shí)際規(guī)定，解決STEPCORBA863/CIMS21王宏典，張友良.虛擬制造技術(shù)及其應(yīng)用.機(jī)械科學(xué)與技術(shù)在緊張忙碌的三個(gè)多月中，完畢了畢業(yè)設(shè)計(jì)。這將是我們最后一次在校園里的學(xué)習(xí)任務(wù)，學(xué)習(xí)的過程是艱辛的，它像帶著刺的玫瑰，而我們的芳香是那些無怨無悔的辛勤園丁們傳授給我們的，在這即將離校的日子，在我們把收獲果實(shí)裝上行囊要帶走的離別時(shí)刻，我們最應(yīng)當(dāng)做的就是向教育過我們的恩師們說一聲“謝謝，謝謝您們的教導(dǎo)”。本次畢業(yè)設(shè)計(jì)重要感謝指導(dǎo)老師代明君老師和協(xié)助指導(dǎo)的牛曙光老師，以及各位機(jī)制教研室老師的大力支持與協(xié)助。在此，我向您們表達(dá)衷心的感謝。通過了三個(gè)多月緊張而有序的認(rèn)真設(shè)計(jì)，我順利完畢了“DZ60振動(dòng)打樁錘”這個(gè)題目的畢業(yè)設(shè)計(jì)，圓滿地完畢了預(yù)定目的。在這過程中我苦惱過設(shè)計(jì)任務(wù)的沉重，興奮于收獲的點(diǎn)點(diǎn)滴滴，我將沿著此樣的道路邁進(jìn)，不畏艱辛，用我最大的力量去換取成功，為我的母校爭光！現(xiàn)在國內(nèi)有關(guān)振動(dòng)樁錘設(shè)計(jì)和制造方面的書籍不是諸多，在期刊等學(xué)術(shù)交流刊物上面發(fā)表的學(xué)術(shù)性論文有某些，但是比較完善地介紹振動(dòng)打樁錘計(jì)算方面的比較少，本次文章的書寫和計(jì)算項(xiàng)目的設(shè)計(jì)都是參考其它機(jī)械產(chǎn)品的內(nèi)容來進(jìn)行的，由于編者水平有限，疏漏之處很難避免，誠懇但愿廣大讀者批評(píng)指正和共同探討。1作者：JohnWilson,動(dòng)態(tài)顧問,dF=W=K=F/d=d=F/K=W/K=自由振動(dòng)自由振動(dòng)被那狀況情形哪里那彈簧是偏斜于是釋放以及允許到自由地頻率或時(shí)期的那振蕩無關(guān)原始的大小原始的偏轉(zhuǎn)的的。那自然地發(fā)生頻率的那自由振動(dòng)fn:受迫振動(dòng) 受迫振動(dòng)當(dāng)能量是持續(xù)地被加到那彈簧質(zhì)量系統(tǒng)由申請(qǐng)振動(dòng)的力在某些受迫振動(dòng)頻率時(shí)的情形ff.兩個(gè)二例子持續(xù)地推一種孩子上去一種搖晃和一失衡旋轉(zhuǎn)電機(jī)元件如果提供充足的能量到克服那阻尼是那動(dòng)作就會(huì)延續(xù)長達(dá)那激勵(lì)延續(xù)之久受迫振動(dòng)能夠取自勵(lì)的或外部地激發(fā)振動(dòng)的形式自激振動(dòng)發(fā)生在激發(fā)力是產(chǎn)生在或上去那懸掛質(zhì)量的時(shí)外部地激發(fā)振動(dòng)發(fā)生在激發(fā)力作用于彈簧的時(shí)候。這是那情形、例當(dāng)那基礎(chǔ)對(duì)此那彈簧附屬于是移動(dòng)時(shí)。傳導(dǎo)能力當(dāng)基礎(chǔ)正在振動(dòng)，并且力整個(gè)彈簧被傳輸?shù)街袛嗟馁|(zhì)量時(shí)候,質(zhì)量的動(dòng)作將會(huì)是來自基礎(chǔ)的動(dòng)作差積。我們將會(huì)認(rèn)為基礎(chǔ)的動(dòng)作是輸入，I,,和質(zhì)量的動(dòng)作響應(yīng),R.比率半徑/我被定義為傳輸度,Tr:Tr=共振在力頻率好低于體系的固有頻率，RI,Tr1。由于作用力的頻率靠近那fffn.時(shí)最大傳遞率發(fā)生，這個(gè)狀況被稱作共振。fn，Rff1.414fn,RITr1質(zhì)量和剛性變更的效應(yīng)。從等式（1）K它是正常地以那希臘語的第六個(gè)字母()或比例C/Cc為特性，其中C是在該構(gòu)造或材料中Ccc2(KM)1/2臨界阻尼是允許該偏斜彈簧質(zhì)量系統(tǒng)到僅僅回到它的均衡部位沒有越過和沒有振蕩的數(shù)1jerk正弦曲線運(yùn)動(dòng)方程f，x：任意時(shí)間，t圖形1速度方 速度是位移隨時(shí)間的變化率即的位移的函數(shù)對(duì)時(shí)間導(dǎo)數(shù)對(duì)瞬時(shí)速度V＝A＝

V=A=22f2D=V/fD=A/22f21000Hz1g0.00002in.的位移；100g0.002in。光學(xué)技術(shù)如果位移是足夠大的，同時(shí)在低頻率，它能夠用一把刻度尺，卡尺，或時(shí)，普通>0.1一束對(duì)準(zhǔn)在一種反射面上光束在強(qiáng)度或者角度的的變化能被使用當(dāng)做一距離批示從電磁和電容傳感器。它的電磁探測器檢測一電磁場產(chǎn)生的變形由這探針和使用那尺寸對(duì)指出從探針到目的的距離。接觸技 各式各樣的相對(duì)運(yùn)動(dòng)傳感器使用直接接觸用兩個(gè)目的來測量在他們震動(dòng)的位移傳感 加速度的兩次積分法藉由逐步增加的有效并且減退解決的數(shù)傳信號(hào)的成本,較多 某些最早的"高頻"振動(dòng)測量以電力學(xué)的速度被做感知器。這些是一種合并一種磁石的地震傳動(dòng)器的型態(tài)增援了通一種軟式彈簧乳濁液系統(tǒng)造形地震的(彈簧質(zhì)量)系統(tǒng)。磁石的構(gòu)件在一種含有一或較多線的多旋轉(zhuǎn)線圈的殼中被中斷。當(dāng)殼在好的在彈簧質(zhì)量系統(tǒng)的自然頻率上面的頻率被振動(dòng)的時(shí)候,質(zhì)量(磁石)與殼振動(dòng)分開。因此，磁石本質(zhì)上不動(dòng)，并且殼以它被附上到的構(gòu)造速度，藉由線圈，移動(dòng)過去它。電的產(chǎn)量被產(chǎn)生對(duì)移動(dòng)過磁場的線圈速度的比例項(xiàng)。速度轉(zhuǎn)換器從10赫茲直至數(shù)百赫茲。他們普通是大的和重,和最后磨耗并且生產(chǎn)不穩(wěn)定的產(chǎn)量。44MHz)映的桿被與最初的桿和都普勒移頻相較用來計(jì)算振動(dòng)表面的速度。次序和疏遠(yuǎn)距離是具激光振動(dòng)計(jì)的一種版本掃瞄橫過一種視覺的磁場激光束,在每個(gè)點(diǎn)測度速度。那然后復(fù)合能被顯示如一種等高線地圖或一種彩色的顯示裝置。振動(dòng)映像能被重疊通一種電視的圖加速度的積分 美國原則由于位移測量，便宜的數(shù)傳信號(hào)解決使以高低不平的大多數(shù)的當(dāng)代振動(dòng)測量被藉由測度加速度做。如果速度或位移數(shù)據(jù)被需要,加速度或者硅應(yīng)變儀類型；整數(shù)的電子學(xué)壓電；和可變電容。盡管不同的電機(jī)械轉(zhuǎn)換機(jī)構(gòu),全部使用彈簧質(zhì)量系統(tǒng)的一種變化,并且被歸類為地震的傳動(dòng)器。振動(dòng)的加速度儀原 全部的振動(dòng)加速度儀使用某些變化一振動(dòng)的或在一狀況piezoresistive(對(duì)于大多數(shù)的應(yīng)用程序，我的個(gè)人偏向是向和內(nèi)部的電子學(xué)的壓電加速計(jì)。這些裝對(duì)使用者重要的大部分是性能和環(huán)境的規(guī)格和價(jià)格。什么在箱里是不恰當(dāng)?shù)娜绻麅x器符號(hào)調(diào)節(jié)相容。每個(gè)類型的加速度儀需要一種不同類型的訊號(hào)調(diào)節(jié)。加速度儀測定類型壓電的（聚乙烯（IEPE電子學(xué)（功率可變電容（貴重貨品壓電的（聚乙烯）PE(piezein這些事物有一種普通的結(jié)晶[性]的分子構(gòu)造,藉由一種凈的進(jìn)氣變更的分派當(dāng)緊張的。或焦熱電的產(chǎn)量,分別地。焦熱電的產(chǎn)量可能是非常大的不必要的信號(hào),普通在長的時(shí)間PE用的高焦熱電的產(chǎn)量。有三個(gè)熱電效應(yīng),將會(huì)在稍后被具體地討論。安培是微微庫倫,或10-12個(gè)庫侖,是某事超出6×106個(gè)電子。S/被討論)。為一種給定的敏捷度允許較小的尺寸,鐵電材料普通是人造的窯業(yè)在哪一結(jié)由于他們是自己，自動(dòng)的意義產(chǎn)生,PE值惡化問題)。能量會(huì)被排出溝外，并且產(chǎn)量會(huì)衰退,盡管固定的輸入加速度/力。PE傳動(dòng)器電壓產(chǎn)量的外面測量需要對(duì)高壓線的動(dòng)態(tài)行為和一前置放大器的輸入特性阻抗;這應(yīng)當(dāng)在1000M的級(jí)上或比較高的擬定充份的低周波響應(yīng)。時(shí)間常數(shù)夠長的,錒加倍的傳動(dòng)器將會(huì)為大多數(shù)的振動(dòng)測量足夠。高阻抗產(chǎn)量PE傳動(dòng)器能移置摩擦電進(jìn)氣,加入被進(jìn)氣變換器測量的進(jìn)氣。摩擦電噪音是一種在典型的同橋電（IEPE輸出端對(duì)體重比的IEPE比聚乙烯或者PR而言是較松的。IEPEPR,化重要地影響相反。相反的，動(dòng)力范疇，輸出電壓的全體可能擺動(dòng),被偏向和順從電壓影響。當(dāng)駕駛高電容載入的時(shí)候，藉由只有在現(xiàn)在的供應(yīng)大變更會(huì)有頻率響應(yīng)的問題。內(nèi)建電子學(xué)的缺點(diǎn)是它普通限定對(duì)一種較狹窄的溫度范疇的傳動(dòng)器。和一種同一的傳動(dòng)器比較起來沒有內(nèi)部的電子學(xué)的設(shè)計(jì),高阻抗版本將會(huì)總是有一種較高的平均無端障時(shí)間(MTBF)被藉由在被制造業(yè)者指定的程度里面增加磁盤電流的數(shù)量治療。矽應(yīng)變計(jì)一地，來自激發(fā)的兩者鉛一定飄浮允許產(chǎn)量線之一被系接地。差別的配備提供共?；亟^PRPRIEPEPR的輸出阻抗時(shí)常夠大的它不能夠駕駛大的電容負(fù)載。美國原則是由于IEPE他們是有幾乎固定數(shù)值的電阻系數(shù)的事物有效同種范疇。美國原則由于任何的電阻器，他們有對(duì)長度的數(shù)值比例項(xiàng)和反的比例到橫斷面面積。如果一種傳統(tǒng)的事物被展,當(dāng)長度增加的時(shí)候，它的寬度減少。兩者的效應(yīng)增加電阻。泊松比定義總值一橫向尺寸是勉強(qiáng)的比擬這數(shù)量這經(jīng)度的尺寸是伸展。予以一種0.3(1.6;1.6深刻的。小型化允許某些PR的自然頻率>1MHz震動(dòng)加速度儀。PRPE磁滯特性。由于他們有直流電反映，他們?cè)趯⒁a(chǎn)生長久計(jì)量時(shí)才使用。PR恒定電流激勵(lì)工作沒有這些用串聯(lián)電阻的問題。然而，PR傳動(dòng)器普通被補(bǔ)整傲慢的固定電壓激發(fā)并且不可能用定流給被需要的性能。PR橋的平衡是它的健康最敏感衡量,并且普通是傳動(dòng)器的總不擬定度的占優(yōu)勢的功效。平衡,有時(shí)叫做了偏向,零偏位,或ZMO(0g基本的應(yīng)變或固定轉(zhuǎn)矩的感知器。內(nèi)部的應(yīng)變變化,舉例來說，環(huán)氧基樹脂蠕升,容易成為某些PR尼系數(shù)0.7聽寫技術(shù)是有用的只有在相對(duì)地低周波:阻尼軍隊(duì)成比例流過速度,并且適宜的流量速度被藉由用大的位移泵流體達(dá)成。這是在那敏感的傳動(dòng)器的一種愉快的巧合他們?cè)诘偷募涌勺冸?繼續(xù)存在極其大加速度過量程的工況是1000倍的測量范疇。元件中的二個(gè)是空氣介質(zhì)，平行板積蓄器的電極。中央的元件用化學(xué)被蝕刻造形被薄又易曲手指中斷的一種硬的中央質(zhì)量。阻尼特性被位于質(zhì)量之上的孔氣體流量控制。 儀類型是開環(huán)裝置在哪一產(chǎn)量由于可察元件的撓曲被直接地讀。在倍力器中-控制,或閉合回路，加速度儀,撓曲信號(hào)被用當(dāng)一種身體上地驅(qū)動(dòng)或再平衡返回平衡位的質(zhì)量電路的反饋。倍力器加速度儀制造業(yè)者建議仰賴位移(也就是,晶體和piezoresistive元件的位移被實(shí)驗(yàn)過的質(zhì)量電再平衡保持極端小,將非線性減到最少。除此之外，閉合回路設(shè)計(jì)表的測量機(jī)構(gòu)原則為基礎(chǔ)。力普通被藉由在一種磁場之前通過在質(zhì)量上的線圈駕駛電流提供。在和一種誤差訊號(hào)給伺服系統(tǒng)。誤差訊號(hào)引發(fā)對(duì)產(chǎn)量的倍力器放大器對(duì)轉(zhuǎn)矩電動(dòng)機(jī)的一種反饋學(xué)的時(shí)候，彈簧在敏感的方向中是如易壞的。不像獨(dú)自地仰賴可察元件(s)的特性其它2APracticalApproachtoVibrationDetectionand——PhysicalPrinciplesandDetectionBy:JohnWilson,theDynamicConsultant,Thistutorialaddressesthephysicsofvibration;dynamicsofaspringmasssystem;damping;displacement,velocity,andacceleration;andtheoperatingprinciplesofthesensorsthatdetectandmeasuretheseproperties.Vibrationisoscillatorymotionresultingfromtheapplicationofoscillatoryorsee,theoscillationmaybecontinuousduringsometimeperiodofinterestoritmaybeintermittent.Itmaybeperiodicornonperiodic,i.e.,itmayormaynotexhibitaregularperiodofrepetition.Thenatureoftheoscillationdependsonthenatureoftheforcedrivingitandonthestructurebeingdriven.Motionisavectorquantity,exhibitingadirectionaswellasamagnitude.Thedirectionofvibrationisusuallydescribedintermsofsomearbitraryaxes.Theoriginfortheorthogonalcoordinatesystemofaxesisarbitrarilydefinedatsomeconvenientlocation.Mostvibratoryresponsesofstructurescanbemodeledassingle-degree-of-freedomspringmasssystems,andmanyvibrationsensorsuseaspringmasssystemasthemechanicalpartoftheirtransductionmechanism.Instiffnessofthespring,K,andthemass,M,orweight,W,ofthemass.Thesecharacteristicsdeterminenotonlythestaticbehavior(staticdeflection,d)ofthestructure,butalsoitsdynamiccharacteristics.IfgistheaccelerationofF=MAW=K=F/d=d=F/K=W/K=DynamicsofaSpringMassThedynamicsofaspringmasssystemcanbeexpressedbythesystem'sbehaviorinfreevibrationand/orinforcedvibration.FreeVibration.Freevibrationisthecasewherethespringisdeflectedandthenjumper,andapendulumorswingdeflectedandlefttofreelyoscillate.Twocharacteristicbehaviorsshouldbenoted.First,dampinginthesystemcausestheamplitudeoftheoscillationstodecreaseovertime.Thegreaterthedamping,thefastertheamplitudedecreases.Second,thefrequencyorperiodoftheoscillationisindependentofthemagnitudeoftheoriginaldeflection(aslongaselasticlimitsarenotexceeded).Thenaturallyoccurringfrequencyofthefreeoscillationsiscalledthenaturalfrequency,fn: (1)ForcedVibration.Forcedvibrationisthecasewhenenergyiscontinuouslyaddedtothespringmasssystembyapplyingoscillatoryforceatsomeforcingfrequency,ff.Twoexamplesarecontinuouslypushingachildonaswingandanunbalancedrotatingmachineelement.Ifenoughenergytoovercomethedampingisapplid,themotionwillcontinueaslongastheexcitationcontinues.Forcedvibrationmaytaketheformofself-excitedorexternallyexcitedvibration.Self-excitedvibrationoccurswhentheexcitationforceisgeneratedinoronthesuspendedmass;externallyexcitedvibrationoccurswhentheexcitationforceisappliedtothespring.Thisisthecase,forexample,whenthefoundationtowhichthespringisattachedismoving.Transmissibility.Whenthefoundationisoscillating,andforceistransmittedfromthemotionofthefoundation.Wewillcallthemotionofthefoundationinput,I,andthemotionofthemasstheresponse,R.TheratioR/Iisdefinedasthetransmissibility,Tr:Tr=RI,andTr1.Astheforcingfrequencyapproachesthenaturalfrequency,transmissibilityincreasesduetoresonance.Resonanceisthestorageofenergyinthemechanicalsystem.Atforcingfrequenciesnearthenaturalfrequency,energyisstoredandbuildsup,resultinginincreasingresponseamplitude.Dampingalsoincreaseswithincreasingresponseamplitude,however,andeventuallytheenergyabsorbedbydamping,percycle,equalstheenergyaddedbytheexcitingforce,andequilibriumisreached.Wefindthepeaktransmissibilityoccurringwhenfffn.Thisconditioniscalledresonance.Isolation.Iftheforcingfrequencyisincreasedabovefn,Rdecreases.WhenwhenR<I,thesystemissaidtobeinisolation.Thatis,someofthevibratorymotioninputisisolatedfromthesuspendedmass.EffectsofMassandStiffnessVariations.FromEquation(1)itcanbeseenthatnaturalfrequencyisproportionaltothesquarerootofstiffness,K,andinverselyproportionaltothesquarerootofweight,W,ormass,M.Therefore,increasingthestiffnessofthespringordecreasingtheweightofthemassincreasesnaturalfrequency.masssystem.Itisusuallytheresultofviscous(fluid)orfrictionaleffects.Allmaterialsandstructureshavesomedegreeofinternaldamping.Inaddition,movementthroughair,water,orotherfluidsabsorbsenergyandconvertsittostraintoheat.And,ofcourse,externalfrictionprovidesdamping.ofdampingwhichallowsthedeflectedspringmasssystemtojustreturntoitsequilibriumpositionwithnoovershootandnooscillation.Anunderdampedsystemwillovershootandoscillatewhendeflectedandreleased.Anoverdampedsystemwillneverreturntoitsequilibriumposition;itapproachesequilibriumDisplacement,Velocity,andSincevibrationisdefinedasoscillatorymotion,itinvolvesachangeofposition,ordisplacement(seeFigure1).shownonthesetimehistoryplots.Velocityisdefinedasthetimerateofchangeofdisplacement;accelerationisthetimerateofchangeofvelocity.Sometechnicaldisciplinesusethetermjerktodenotethetimerateofchangeofacceleration.SinusoidalMotionEquation.Thesingle-degree-of-freedomspringmassinforcedvibration,maintainedataconstantdisplacementamplitude,exhibitsvs.timetracesoutasinusoidalcurve.GivenapeakdisplacementofX,frequencyf,andinstantaneousdisplacementx: (2)atanytime,VelocityEquation.Velocityisthetimerateofchangeofdisplacement,which (3)Sincevibratorydisplacementismostoftenmeasuredintermsofpeak-to-peak,doubleamplitude,displacementD=2X: (4)Ifwelimitourinteresttothepeakamplitudesandignorethetimevariationandphaserelationships: (5)V=peakAccelerationEquation.Similarly,accelerationisthetimerateofchangeofvelocity,thederivativeofthevelocityexpression: (6) (7)A=peakItthuscanbeshownV=A=22f2D=V/D=A/22Fromtheseequations,itcanbeseenthatlow-frequencymotionislikelytoexhibitlow-amplitudeaccelerationseventhoughdisplacementmaybelarge.Itcanalsobeseenthathigh-frequencymotionislikelytoexhibitlow-amplitudedisplacements,eventhoughaccelerationislarge.Considertwoexamples:At1Hz,1in.pk-pkdisplacementisonly~0.05gacceleration;10in.~0.5g?At1000Hz,1gaccelerationisonly~0.00002in.displacement;100g~0.002MeasuringVibratoryOpticalTechniques.Ifdisplacementislargeenough,asatlowitcanbemeasuredwithascale,calipers,orameasuringmicroscope.Athigherfrequencies,displacementmeasurementrequiresmoresophisticatedopticalHigh-speedmoviesandvideocanoftenbeusedtomeasuredisplacementsandareespeciallyvaluableforvisualizingthemotionofcomplexstructuresandmechanisms.Thetwomethodsarelimitedbyresolutiontofairlylargedisplacementsandlowfrequencies.Strobelightsandstroboscopicphotographyarealsousefulwhendisplacementsarelargeenough,usually>0.1in.,tomakethempractical.Thechangeinintensityorangleofalightbeamdirectedontoareflectivesurfacecanbeusedasanindicationofitsdistancefromthesource.Ifthedetectionapparatusisfastenough,changesofdistancecanbedetectedaswell.Themostsensitive,accurate,andpreciseopticaldeviceformeasuringdistanceordisplacementisthelaserinterferometer.Withthisapparatus,areflectedlaserbeamismixedwiththeoriginalincidentbeam.Theinterferencepatternsformedbythephasedifferencescanmeasuredisplacementdownto<100nm.NISTandothernationalprimarycalibrationagenciesuselaserforprimarycalibrationofvibrationmeasurementinstrumentsatfrequenciesupto25kHz.ElectromagneticandCapacitiveSensors.AnotherimportantclassofTheseareprobesthataretypicallybuiltintomachinerytodetectthemotionofshaftsinsidejournalbearingsortherelativemotionofothermachineelements.Thesensorsmeasurerelativedistanceorproximityasafunctionofeitherelectromagneticorcapacitive(electrostatic)couplingbetweentheprobeandtheanelectricallyconductivetarget.Inmostcases,theymustbecalibratedforaspecifictargetandspecificmaterialcharacteristicsinthegapbetweenprobeandtarget.oneofthemostpopulartypesuseseddycurrentsgeneratedinthetargetasitsmeasurementmechanism.Moreaccurately,thistypeofsensorusestheenergydissipatedbytheeddycurrents.Thegreaterthedistancefromprobetotarget,thelesselectromagneticcoupling,thelowerthemagnitudeoftheeddycurrents,thedistortionofanelectromagneticfieldgeneratedbytheprobeandusethatmeasurementtoindicatethedistancefromprobetotarget.andthetargetandarecalibratedtoconvertthecapacitancetodistance.Capacitanceisaffectedbythedielectricpropertiesofthematerialinthegapaswellasbydistance,socalibrationcanbeaffectedbyachangeoflubricantorcontaminationofthelubricantinamachineenvironment.ContactTechniques.AvarietyofrelativemotionsensorsusedirectLVDTs,cablepositiontransducers(stringpots),andlinearpotentiometers.AllofthesedevicesdependonmechanicallinkagesandelectromechanicalSeismicDisplacementTransducers.Thesedevices,discussedindetaillater,DoubleIntegrationofAcceleration.Withtheincreasingavailabilityanddecreasingcostofdigitalsignalprocessing,moreapplicationsareusingthemoreruggedandmoreversatileaccelerometersassensors,thendoubleintegratingtheaccelerationsignaltoderivedisplacements.Whileolderanalogintegrationtechniquestendedtobenoisyandinaccurate,digitalprocessingcanprovidequitehigh-quality,high-accuracyresults.MeasuringVibratoryTransducers.Someoftheearliest"high-frequency"vibrationweremadewithelectrodynamicvelocitysensors.Theseareatypeofseismictoformtheseismic(springmass)system.Themagneticmemberissuspendedinahousingthatcontainsoneormoremultiturncoilsofwire.Whenthehousingisthemass(magnet)isisolatedfromthehousingvibration.Thus,themagnetisessentiallystationaryandthehousing,withthecoils,movespastitattheproportionaltothevelocityofthecoilmovingthroughthemagneticfield.Velocitytransducersareusedfrom~10HzuptoafewhundredHz.Theytendtobelargeandheavy,andeventuallywearandproduceerraticoutputs.LaserVibrometers.Laservibrometersorlaservelocimetersarerelativelyinstrumentscapableofprovidinghighsensitivityandaccuracy.Theyuseafrequency-modulated(typicallyaround44MHz)laserbeamreflectedfromavibratingsurface.ThereflectedbeamiscomparedwiththeoriginalbeamandtheOneversionoflaservibrometerscansthelaserbeamacrossafieldofvision,IntegrationofAcceleration.Aswithdisplacementmeasurements,low-digitalsignalprocessingmakesitpracticaltouserugged,reliable,versatileMeasuringVibratoryAccelerationMostmodernvibrationmeasurementsaremadebymeasuringacceleration.If(velocity)ordoubleintegrated(displacement).Someaccelerometersignalconditionershavebuilt-inintegratorsforthatpurpose.Accelerometers(accelerationsensors,pickups,ortransducers)areavailableinawidevarietyofsizes,shapes,performancecharacteristics,andprices.Thefivebasictransducertypesareservoforcebalance;crystal-typeorpiezoelectric;andvariablecapacitance.Despitethedifferentelectromechanicaltransductionmechanisms,alluseavariationofthespringmasssystem,andareclassifiedasseismictransducers.SeismicAccelerometerPrinciple.Allseismicaccelerometersusesomevariationofaseismicorproofmasssuspendedbyaspringstructureinacase(seeFigure3).Whenthecaseisaccelerated,theproofmassisalsoacceleratedbytheforcetransmittedthroughthespringstructure.Thenthedisplacementofthespring,thedisplacementofthemasswithinthecase,ortheforcetransmittedbythespringistransducedintoanelectricalsignalproportionaltoAccelerometers.Transducersdesignedtomeasurevibratoryaccelerationarecalledaccelerometers.Therearemanyvarietiesincludingstraingauge,servoforcebalance,piezoresistive(siliconstraingauge),piezoelectric(crystal-type),variablecapacitance,andintegralelectronicpiezoelectric.Eachbasictypehasmanyvariationsandtradenames.Mostmanufacturersprovideexcellentapplicationsengineeringassistancetohelptheuserchoosethebesttypefortheapplication,butbecausemostofthesesourcessellonlyoneortwotypes,theytendtobiastheirassistanceaccordingly.Formostapplications,mypersonalbiasistowardpiezoelectricaccelerometerswithinternalelectronics.Theprimarylimitationofthesedevicesistemperaturerange.Althoughtheyexhibitlow-frequencyroll-off,theyareavailablewithextremelylow-frequencycapabilities.Theyprovideapreamplifiedlow-impedanceoutput,simplecabling,andsimplesignalconditioning,andgenerallyhavethelowestoverallsystemcost.Mostimportanttotheuseraretheperformanceandenvironmentalspecificationsandtheprice.What'sinsidetheboxisirrelevantiftheinstrumentmeetstherequirementsoftheapplication,butwhenaddingtoexistinginstrumentationitisimportanttobesurethattheaccelerometeriscompatiblewiththesignalconditioning.Eachtypeofaccelerometerrequiresadifferenttypeofsignalconditioning.AccelerometerTypes.Themostcommonseismictransducersforshockandvibrationmeasurementsare:Piezoelectric(PE);high-impedanceIntegralelectronicspiezoelectric(IEPE);low-impedancePiezoresistive(PR);siliconstraingaugeVariablecapacitance(VC);low-level,low-ServoforcePiezoelectric(PE)sensorsusethepiezoelectriceffectsofthesensingelement(s)toproduceachargeoutput.BecauseaPEsensordoesnotrequireanexternalpowersourceforoperation,itisconsideredself-generating.The"spring"sensingelementsprovideagivennumberofelectronsproportionaltotheandman-madematerials,mostlycrystalsorceramicsandafewpolymers,displaythischaracteristic.Thesematerialshavearegularcrystallinemolecularstructure,withanetchargedistributionthatchangeswhenstrained.Piezoelectricmaterialsmayalsohaveadipole(whichisthenetseparationofpositiveandnegativechargealongaparticularcrystaldirection)whenunstressed.Inthesematerials,fieldscanbegeneratedbydeformationfromstressortemperature,causingpiezoelectricorpyroelectricoutput,respectively.Thepyroelectricoutputscanbeverylargeunwantedsignals,generallyoccurringoverthelongtimeperiodsassociatedwithmosttemperaturechanges.PolymerPEmaterialshavesuchhighpyroelectricoutputthattheywereoriginallyusedasthermaldetectors.Therearethreepyroelectriceffects,whichwillbediscussedlaterindetail.andmomentum,chargeisalwaysconserved.)Whenanelectricfieldisgeneratedalongthedirectionofthedipole,metallicelectrodesonfacesattheoppositethesignalconditioning,totheothersideofthesensortocancelthegeneratedbetweentheelectrodes.AcommonunitofchargefromaPEaccelerometeristhepicocoulomb,or10-12coulomb,whichissomethingover6×106electrons.ChoosingamongthemanytypesofPEmaterialsentailsatradeoffamongchargesensitivity,dielectriccoefficient(which,withgeometry,determinesthecapacitance),thermalcoefficients,maximumtemperature,frequencycharacteristics,andstability.ThebestS/Nratiosgenerallycomefromthehighestpiezoelectriccoefficients.Naturallyoccurringpiezoelectriccrystalssuchastourmalineorquartzgenerallyhavelow-chargesensitivity,aboutone-hundredththatofthemorecommonlyusedferroelectricmaterials.(Buttheselow-chargeoutputmaterialsaretypicallyusedinthevoltagemode,whichwillbediscussedlater.)Allowingsmallersizeforagivensensitivity,ferroelectricmaterialsareusuallyman-madeceramicsinwhichthecrystallinedomains(i.e.,regionsinwhichdipolesarenaturallyaligned)arethemselvesalignedbyaprocessofartificialPolarizationusuallyoccursattemperaturesconsiderablyhigherthanoperatingtemperaturestospeedtheprocessofalignmentofthedomains.Depolarization,orrelaxation,canoccuratlowertemperatures,butatverymuchlowerrates,andcanalsooccurwithappliedvoltagesandpreloadpressures.Depolarizationalwaysresultsintemporaryorpermanentlossofsensitivity.Tourmaline,anaturalcrystalthatdoesnotundergodepolarization,isparticularlyusefulatveryhightemperatures.Becausetheyareself-generating,PEtransducerscannotbeusedtomeasuresteady-stateaccelerationsorforce,whichwouldputafixedamountofenergyintothecrystal(aone-waysqueeze)andthereforeafixednumberofelectronsattheelectrodes.Conventionalvoltagemeasurementwouldbleedelectronsaway,asdoesthesensor'sinternalresistance.(Hightemperatureorhumidityinthetransducerwouldexacerbatetheproblembyreducingtheresistancevalue.)Energywouldbedrainedandtheoutputwoulddecay,despitetheconstantinputExternalmeasurementofPEtransducervoltageoutputrequiresspecialattentiontothecable'sdynamicbehavioraswellastheinputcharacteristicsofthepreamplifier.Sincecablecapacitancedirectlyaffectsthesignalamplitude,excessivemovementofthecableduringmeasurementcancausechangesinitscapacitanceandshouldbeavoided.Closeattentionshouldalsobepaidtothepreamp'sinputimpedance;thisshouldbeontheorderof1000M orhighertoensuresufficientlow-frequencyresponse.Inpractice,achargeamplifierisnormallyusedwithaPEInsteadofmeasuringvoltageexternally,achargeshouldbemeasuredwithachargeconverter.Itisahigh-impedanceopampwithacapacitorasitsfeedback.Itsoutputisproportionaltothechargeattheinputandthefeedbackcapacitor,andisnearlyunaffectedbytheinputcapacitanceofthetransducerorattachedcables.Thehigh-passcornerfrequencyissetbythefeedbackcapacitorandresistorinachargeconverter,andnotthetransducercharacteristics.(Thetransducerresistancechangesnoisecharacteristics,notthefrequency.)Iftimeconstantsarelongenough,theAC-coupledtransducerwillsufficeformostvibrationmeasurements.isthattheymustbeusedwith"noise-treated"cables;otherwise,motioninthecoaxialcables.MostPEtransducersareextremelyrugged.Eachofthevariousshapesandsizesavailablecomeswithitsownperformancecompromises.Themostcommontypesofthistransducerarecompressionandsheardesigns.Sh