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1、滁州學院12級機械本一班主講：胡恩生編輯：金冉賈富文資料搜集：胡恩生蔣杉杉14·3·25GearsDefinition?of?Gears:A?gear?is?a?rotating?machinepart?having?cutteeth,?orcogs,whichmeshwith?another?toothed?part?in?order?to?transmit?torque.?Two?or?mors?gears?working?in?tandem?are?called?atransmissionand?can?produce?a?mec
2、hanical?advantage?through?a?gear?ratio?and?thus?may?be?considered?a?simple?machine.?Geared?devices?can?change?the?speed,?magnitude,?and?direction?of?a?power?source.?The?most?common?situation?is?for?a?gear?to?mesh?withanother?gear,?however?a?gear?can?also?mesh?a?non-rotat
3、ing?toothed?part,called?a?rack,thereby?producing?translation?instead?of?rotation.我的翻譯：齒輪是一個旋轉(zhuǎn)的機械零件，有削減的齒，它與另一個齒的一部分，以便傳輸扭矩。兩個或多個齒輪同步工作被稱為傳動系統(tǒng)，并且能夠產(chǎn)生通過機械傳動比的優(yōu)勢，因此可以被認為是簡單的機械。減速裝置可以改變的速度，規(guī)模，以及一個電源方向。最常見的情況是謙卑地與另一個齒輪，齒輪，齒輪也不過一目了非旋轉(zhuǎn)式齒形的一部分，稱為機架，從而產(chǎn)生傳動，而不是旋轉(zhuǎn)。Gears?are?direct-
4、contact?bodies,operating?in?pairs,?that?transmit?motionand?force?from?one?rotating?shafttoanother,?or?from?a?shaft?to?a?slide?（滑動部件）(rack),by?means?of?successively?engagingProjections（突出物）called?teeth.Therearefourmaintypesofgears：spur，helical，worm，andbevel。spurandhelical
5、gears 直齒輪和斜齒輪A?gear?having?tooth?elements?that?are?straight?and?parallel?to?its?axis?is?knowns?as?a?spur?gear?.A?spur?pair?can?be?used?to?connect?parallel?shafts?only?.?Parallel?shafts?,however?,can?also?be?connected?by?gears?of?another?type?,and?a?spur?gear?can?be?mated
6、?with?a?gear?of?adifferent?type?.To?prevent?jamming?as?a?result?of?thermal?expansion?,to?aid?lubrication?and?to?compensate?for?unavoidable?inaccuracies?in?manufacture?,all?powertransmitting?gears?must?have?backlash?.this?meansthat?on?pitch?circles?of?a?mating?pair?,the?s
7、pace?width?on?the?pinion?must?be?slinghtly?greather?than?the?tooth?thickness?on?the?gear,and?vice?versa（反之亦然）。On?instrument?gears?,?backlash?can?be?eliminathed?by?using?a?gear?split?down?the?middle?,one?half?being?ratable?to?the?other?.A,spring?forces?the?split?gear?teet
8、h?to?occupy?the?full?width?of?the?pinion?space?.Helical?gears?have?certainadvantages,for?example?,?when
