汽車底盤構造—變速器2ppt課件

1、 汽車底盤構造 變速器與分動器主講孟慶雨 第一節(jié)第一節(jié) 變速器的功用和類型變速器的功用和類型n 功用：功用： n （1改變傳動比，擴大驅(qū)動輪轉(zhuǎn)矩和轉(zhuǎn)速改變傳動比，擴大驅(qū)動輪轉(zhuǎn)矩和轉(zhuǎn)速的變化范圍，以適應經(jīng)常變化的行駛條件，使的變化范圍，以適應經(jīng)常變化的行駛條件，使發(fā)動機在有利的工況下工作。發(fā)動機在有利的工況下工作。 n （2在發(fā)動機旋轉(zhuǎn)方向不變的前提下，使在發(fā)動機旋轉(zhuǎn)方向不變的前提下，使汽車倒退行駛。汽車倒退行駛。 n （3利用空檔中斷動力傳遞，以使發(fā)動機利用空檔中斷動力傳遞，以使發(fā)動機能夠起動、怠速，并便于變速器換檔或進行動能夠起動、怠速，并便于變速器換檔或進行動力輸出。力輸出。1.變速器的功

2、用和組成2.變速器的類型變速器的類型1按傳動比變化方式不同：按傳動比變化方式不同：有級式變速器；用齒輪傳動，有若干個定值傳有級式變速器；用齒輪傳動，有若干個定值傳動比動比無級式變速器：采用電力或液力變矩器傳動，無級式變速器：采用電力或液力變矩器傳動，傳動比可在一定的數(shù)值范圍內(nèi)連續(xù)變化。傳動比可在一定的數(shù)值范圍內(nèi)連續(xù)變化。 綜合式變速器：綜合式變速器： 由液力變矩器和行星齒輪式變速器組成，傳由液力變矩器和行星齒輪式變速器組成，傳動比可在幾個范圍內(nèi)連續(xù)變化。動比可在幾個范圍內(nèi)連續(xù)變化。2按操縱方式不同：按操縱方式不同：強制操縱式：靠駕駛員直接操縱變速桿換檔強制操縱式：靠駕駛員直接操縱變速桿換檔 。

3、自動操縱式：換檔自動進行。自動操縱式：換檔自動進行。 半自動操縱式：常用的幾個檔位自動操縱；預半自動操縱式：常用的幾個檔位自動操縱；預選式選式變速器組成變速器組成變速傳動機構：改變轉(zhuǎn)速比、改變轉(zhuǎn)矩、改變方向操縱機構：實現(xiàn)換檔3.變速器的組成變速器的組成變速傳動機構（按傳動齒輪軸數(shù)）三軸式齒輪變速傳動兩軸式齒輪變速傳動第二節(jié) 變速器的變速傳動機構一、有級式變速器變速傳動機構的組成、工作原理和常見的換檔方式1.變速傳動機構的組成變速傳動機構主要由齒輪、軸及變速器殼體等零部件組成。第二節(jié) 變速器的變速傳動機構輸入軸中間軸輸出軸倒檔軸變速齒輪結合套殼體2.變速傳動機構的工作變速傳動機構的工作原理原理

4、1） 利用不同齒數(shù)利用不同齒數(shù)的齒輪對相互嚙合，的齒輪對相互嚙合，以改變變速器的傳動以改變變速器的傳動比；比；i12=n1/n2= z2/z1= M2/M1z1 ，n1 ， M1為主動為主動齒輪的參數(shù)。齒輪的參數(shù)。 z2 ，n2 ， M2為從動為從動齒輪的參數(shù)。齒輪的參數(shù)。從動輪2主動輪1i=主動齒輪齒數(shù)主動齒輪齒數(shù)從動齒輪齒數(shù)從動齒輪齒數(shù)GearsGears are used to multiply either torque or speed as power is transferred from one shaft to another. In this case the gear r

5、atio is 40 20 or 2:1. The blue gear will have twice the torque but one-half the speed as the green gear.Input: 20 TeethOutput: 40 TeethGear TypesThe most common gear types are Spur (left) and Helical (right) gears. Spur gears have the teeth cut parallel to the shaft. The teeth of a helical gear are

6、cut at an angle. A helical gear runs quieter, costs more, and generates a side thrust under load.Spur GearsHelical Gearsn 2通過增加齒輪傳動的對數(shù)，以實現(xiàn)倒檔。 Idler GearsAn Idler gear (orange) can be put in a gear train to reverse direction of rotation. A simple idler, as shown, will not change the gear ratio. In th

7、is case, the gear ratio is 40 (blue output gear) divided by 20 (green input gear) = 2:1, and both the input and output rotate clockwise.Clockwise RotationIdler Gear, Counterclockwise Rotation3常見的換檔方式（1利用滑動齒輪換檔 沖擊、噪聲、損壞齒端面、舒適性降低。倒擋常用。（2利用接合套換檔 同時承受換檔沖擊的齒數(shù)多，輪齒不參與換檔，不會發(fā)生早期損壞。不能消除換檔沖擊。（3利用同步器換檔 迅速、無沖擊、無

8、噪聲換檔 ；與熟練程度無關。加速性、經(jīng)濟性和行駛安全性提高。二、兩軸式變速器Manual Transaxle OperationPurposeA manual transaxle is used in many FWD vehicles. It provides various gear ratios that are necessary to transfer power from the engine and clutch to the drive shafts and wheels.To ClutchTo Drive shaftConstructionMost transaxles ha

9、ve three major shafts:an input shaft that connects to the clutch disc with the driving gears, a main/intermediate shaft with the driven gears, andthe output shaft with the differentialInput ShaftIntermediate ShaftOutput: Final Drive & DifferentialBearingsA pair of tapered roller bearings (orange

10、) are used to support each of the two major shafts and differential. This type of bearing allows the shaft to rotate freely, but eliminates any end play. Some transmissions use ball bearings for this same purpose.優(yōu)點：直徑較?。粚挾容^大；容量大；可承受高負荷；三元件基本位置關系能使?jié)L子正確對中，軸承可靠性和壽命提高；軸和齒輪的剛度提高，齒輪噪聲降低，減少脫檔可能。Speed Gear

11、s & SynchronizersA synchronizer assembly normally has a speed gear positioned on each side of it. The speed gears float on the shaft. The synchronizer sleeve engages the clutching teeth of the speed gear to transfer its motion to the shaft.1st 4th 3rd Rev. 5th 2nd Fixed GearsOne of the gears, ei

12、ther the driving or driven gear, for each gear ratio is fixed solidly to one of the shafts. It meshes with a speed gear to provide the proper gear ratio.Rev. 5th 2nd 1st 4th 3rd Shifting GearsA rather complex mechanism connects the gear shift lever to the shift forks inside the transaxle. The shift

13、forks move the synchronizer sleeves to make the shifts from one gear range to another.To Shift LeverShift ForkNeutralIf each of the synchronizers assemblies is in neutral and the reverse idler gear is not in mesh, power is not able to get from the input shaft to the intermediate shaft. The input sha

14、ft and the speed gears can rotate, but the intermediate shaft will not be driven.All synchros. are in neutral, center position1st GearThis is the lowest gear ratio with the smallest gear on the input shaft driving the largest gear on the intermediate shaft. In this example a 12 tooth gear drives a 4

15、2 tooth gear. 42 12 = 3.501st Gear, Driving1st Gear, Driven1-2 Synchro., Shifted to 1st2nd GearThe 1-2 synchronizer is moved to engage the 2nd speed gear. Now a 14 tooth gear drives a 35 tooth gear. The ratio is: 35 14 = 2.502nd Gear, Driving2nd Gear, Driven1-2 Synchro., Shifted to 2nd 3rd GearWith

16、the 1-2 synchronizer in neutral, the 3-4 synchronizer is moved to engage the 17 tooth speed gear. It drives a 21 tooth gear. The ratio is 21 17 = 1.24:1.3rd Gear, Driving3rd Gear, Driven3-4 Synchro., Shifted to 3rd 4th GearThe 3-4 synchronizer is moved to engage the 19 tooth speed gear that is drive

17、s an 18 tooth gear. The ratio is 18 19 = 0.95:1. Note that this is an overdrive ratio so the intermediate shaft will rotate faster than the input shaft.4th Gear, Driving4th Gear, Driven3-4 Synchro. Shifted to 4th 5th GearThe 5th gear synchronizer is moved to engage the 15 tooth 5th speed gear. It is

18、 driven by a 20 tooth gear so the ratio is 15 20 = 0.75:1, another overdrive ratio.5th Gear, Driving5th Gear, Driven5-Rev Synchro. Shifted to 5thReverseThe 5-Reverse synchro. is shifted into mesh with the 42 tooth Rev. speed gear. A 12 tooth Rev. Gear drives it. The idler gear is used to change the

19、direction of rotation. The ratio is 42 12 = 3.50:1Rev. Gear, DrivingRev. Gear, Driven5-Rev. Synchro. Shifted to Rev.Rev. Idler GearOther Reverse TypesSome transaxles construct the 1-2 synchronizer sleeve with the reverse gear teeth surrounding it. The reverse idler gear is shifted into mesh with the

20、 reverse drive gear and the driven gear on the synchro. Sleeve. This is difficult to illustrate because the idler gear and shaft are positioned behind the other gears.Rev. Idler GearRev. Drive Gear1-2 Synchro. + 1st & 2nd Speed GearsRev. Driven GearInput ShaftFinal DriveA 20 tooth gear on the in

21、termediate shaft drives the 80 tooth ring gear on the differential. Power is transferred from the ring gear to the differential case and through the differential gears to the CV joints and front driveshafts. The ratio is 80 20 = 4:1Pinion GearRing GearDiff. Side GearDiff. Pinion GearCV JointOverall

22、RatiosThe overall ratio between the engine and the drive wheels is effected by both gear ratios. These ratios become: 1st gear: 3.50 X 4 = 14:1 2nd gear: 2.50 X 4 = 10:1 3rd Gear: 1.24 X 4 = 4.96:1 4th Gear: 0.95 X 4 = 3.80:15th Gear: 0.75 X 4 = 3:1 Reverse: 3.50 X 4 = 14:1二、兩軸式變速器二、兩軸式變速器n運用：運用： FF

23、 RR n特點：特點： n 輸入軸與輸出軸平行，無中間軸。輸入軸與輸出軸平行，無中間軸。 n組成：組成： n 輸入軸、輸出軸、倒檔軸、軸承、變輸入軸、輸出軸、倒檔軸、軸承、變速齒輪速齒輪桑塔納轎車變速器結構簡圖桑塔納轎車變速器結構簡圖桑塔納轎車兩軸式變速器桑塔納轎車兩軸式變速器n結構分析：結構分析：n一軸：一、二檔齒輪與軸一體；三、四檔齒輪與軸通過軸承空套一軸：一、二檔齒輪與軸一體；三、四檔齒輪與軸通過軸承空套軸上。軸上。 n二軸：一、二檔齒輪與通過軸承連接；三、四檔齒輪與軸一體。二軸：一、二檔齒輪與通過軸承連接；三、四檔齒輪與軸一體。一、二檔傳動路線三、四檔傳動路線倒檔傳動路線三、三軸式變速

24、器 三軸是指汽車前進時，傳遞動力的軸有第一軸、中間軸和第二軸，直接檔除外。 換檔原理一軸中間軸二軸三軸式變速器結構圖傳動方向結合齒圈結合套齒花鍵轂 跳檔方向四、防止自動跳檔的措施四、防止自動跳檔的措施 （1切薄齒式切薄齒式利用接合套換檔的變速器，由于接合套與齒圈利用接合套換檔的變速器，由于接合套與齒圈的接合長度較短，同時汽車行駛時需要經(jīng)常換的接合長度較短，同時汽車行駛時需要經(jīng)常換檔，頻繁撥動接合套將使齒端發(fā)生磨損。汽車檔，頻繁撥動接合套將使齒端發(fā)生磨損。汽車行駛中可能會因振動等原因造成接合套與齒圈行駛中可能會因振動等原因造成接合套與齒圈脫離嚙合，即發(fā)生自動跳檔。脫離嚙合，即發(fā)生自動跳檔。（2斜

25、面齒式斜面齒式結合齒圈結合套齒花鍵轂結合齒圈傳動方向接合套和接合齒圈的齒端制成倒斜面（3接合套的齒端制成凸肩接合套的齒端制成凸肩 五、組合式變速器5-Speed Manual TransmissionPurposeA manual transmission is used in many RWD and 4WD vehicles. It provides the various gear ratios that are necessary to transfer power from the engine and clutch to the drive shafts and wheels.En

26、gine Clutch Transmission Driveshaft Drive AxleConstructionManual transmissions have three major shafts: an input shaft/ main drive gear that connects to the clutch disc, a counter shaft that is commonly called a cluster gear, and the main shaft/output shaft with the driven gears and synchronizers.Ma

27、in ShaftInput ShaftCluster GearBearingsThe main drive gear and main shaft are each supported by a ball or roller bearing with a pilot bearing where the main shaft fits into the main drive gear. The cluster gear is supported by a pair of bearings. These bearings are colored orange.Cluster Gear Bearin

28、gsMain shaft bearingPilot BearingMain Drive Gear BearingSpeed Gears & SynchronizersA synchronizer assembly normally has two speed gears, one on each side of it. The speed gears float on the main shaft. The synchronizer sleeve engages the clutching teeth of a speed gear to transfer its motion to

29、the shaft.1-2 Synchro.3-4 Synchro.5-Rev. Synchro.3rd Speed Gear2nd Speed Gear5th Speed Gear1st Speed GearReverse Speed Gear6-Speed Main Shaft3-4 Synchro. 1-2 Synchro. 5-6 Driven Gear Rev. Synchro. OutputSpeed Gear Journals:3rd 2nd 1st ReverseThis mainshaft has 3 splined areas that connect to the syn

30、chronizer hubs, a set of splines for the 5-6 fixed/driven gear, 1 set of output splines for the drive shaft slip joint. And 4 smooth journals for the speed gears.Fixed GearsThe main drive gear and cluster gears are normally made as part of their shaft. These are the driving gears for each of the gea

31、r ranges.Shifting GearsMost SUV and pickup transmissions incorporate the shift mechanism into the the top of the unit. Movement of the gear shit lever will move one of the shift forks connected to the synchronizer sleeve.Shift LeverShift RailShift ForkShift DetentsMost detents are spring-loaded ball

32、s (red) that are pushed into one of two or three notches in a shift rail or cam. They are used to hold the shift rail in an exact position which places the synchro. sleeve or gear in an exact position. The center shift rail detents are in back of the rail.Detent Ball Detent SpringShift Rail Shift Fo

33、rkShift InterlocksThis 5-speed transmission has three shift rails that transmit motion from the shift lever to the shift forks. When one of the rails is moved from neutral, the plugs are moved sideways to lock the other rails in placeShift RailsPlug Pin PlugNeutralIf each of the synchronizers assemb

34、lies is in neutral and the reverse idler gear is not in mesh, power is not able to get from the speed gears to the main shaft. The input shaft, cluster gear, and speed gears rotate but not the main shaft.All Synchros. In neutral, center positionNeutralIn neutral with the clutch engaged, the input sh

35、aft will spin, but there will be no power transferred. Input from clutchOutput to drive shaftNeutral power flow5-Speed gearboxDouble ReductionManual transmission gear ratios are effected by two gear sets. The first (input) is the ratio between the main drive gear and cluster gear. The second is the

36、ratio between the drive and driven gears for each gear range.15 Tooth Main Drive Gear20 Tooth Cluster Gear1st GearsInput reduction: 20 15 = 1.33:1 Reduction, 1st Gears: 3:1 1st Gear Ratio: 1.3 X 3 = 3.9:11st GearThe 1-2 synchronizer is moved to engage the clutching teeth on the 45 tooth 1st speed ge

37、ar. It is driven by a 15 tooth gear on the cluster gear. The 1st gear ratio is 3.9:1.1-2 Synchro. Shifted to 1st 1st Speed Gear, Driven1st Gear, Driving2nd GearThe 1-2 synchronizer is moved to engage the 40 tooth, 2nd speed gear. It is driven by a 20 tooth gear on the cluster gear. The cluster to ma

38、in shaft ratio is 1.3:1, and the 2nd gear ratio is 2:1 X 1.3:1 = 2.6:1.2nd Speed Gear, Driven2nd Gear, Driving1-2 Synchro. Shifted to 2nd 3rd GearThe 3-4 synchronizer is moved to engage the 20 tooth 3rd speed gear. It is driven be a 15 tooth gear on the cluster gear. The gear ratio is: 1.3:1 X 1.3:1

39、 = 1.69:1.3-4 Synchro. Shifted to 3rd 3rd Gear, Driving3rd Gear, Driven4th GearThe 3-4 synchronizer is moved to engage the clutching teeth on the main drive gear. Power is transmitted directly to the main shaft so the ratio is 1:1, direct drive.3-4 Synchro. Shifted to 4th Main Drive GearMain Shaft5t

40、h GearThe 5-Rev. synchronizer is moved to engage the 20 tooth 5th speed gear. It is driven by a 30 tooth gear that is part of the cluster gear. The ratio is 0.66:1 X 1.3:1 = 0.86:15th Gear, Driving5-Rev. Synchro Shifted to 5th5th Gear, DrivenOther 5th Gear TypesThe 5th driving gear in this transmiss

41、ion is a speed gear mounted on the cluster gear along with the 5th gear synchronizer. The 5th driven gear is attached to the mainshaft.5th Driven Gear5th Gear Synchronizer5th Speed GearReverseThe 5-Reverse synchro. is shifted into mesh with the 45 tooth Rev. speed gear. A 15 tooth Rev. gear on the c

42、luster drives it through the Rev. idler gear. The idler gear is used to change the direction of rotation. The reverse gear ratio is 3:1 X 1.3:1 = 3.9:1.5-Rev. Synchro. Shifted to Rev.Rev. Gear, DrivingRev. Idler GearRev. Gear, DrivenRev. Gear, DrivenOther Reverse TypesSome 4 & 5 speed transmissi

43、ons use a reverse driven gear that surrounds the 1-2 synchronizer sleeve. The reverse idler gear (mounted behind the other gears) is shifted into mesh with the reverse driving gear on the cluster gear and the reverse driven gear. All three of these gears are spur gears.Reverse Driven GearReverse Dri

44、ve GearReverse Idler Gear第三節(jié)第三節(jié) 同步器同步器n無同步器時變速器的換檔過程無同步器時變速器的換檔過程 1、從低檔換入高檔、從低檔換入高檔脫離瞬間：脫離瞬間： V4=VJ V5VJ、 V4 保持空檔片刻保持空檔片刻 V5降低，降低，VJ、 V4變變化不大化不大 在在VJ與與V5相等時掛入相等時掛入五檔五檔 五檔齒輪四檔齒輪中間軸結合套花鍵轂結合齒圈結合齒圈2、從高檔換入低檔、從高檔換入低檔n脫離瞬間：脫離瞬間： nV5=VJn V4VJ、 V5 n抬起離合器踏板，踩抬起離合器踏板，踩一下油門踏板一下油門踏板 ，V4升升高，高，VJ變化不大變化不大 n在在VJ與與V4

45、相等時掛入相等時掛入四檔四檔五檔齒輪四檔齒輪中間軸結合套花鍵轂結合齒圈結合齒圈四檔工作：V3=V4，欲換檔踩離合器接合套左移處空擋因V4V2 V3V4V3V4空檔時：V4比V3下降得快，直線V3、V4不會有交點，不可能達到自然同步狀態(tài)，駕駛員應在變速器退到空檔后，立即抬起離合器，同時踩加速踏板，使發(fā)動機連同離合器和第一軸都從B點升速，讓V4V3，再踩離合器等到V3=V4，可以換檔。V3V4t2t3tVBAAV3V4二、同步器構造及工作原理二、同步器構造及工作原理1、功用：使結合套與待嚙合齒圈迅速同步，、功用：使結合套與待嚙合齒圈迅速同步，縮短換檔時間，同時防止嚙合時齒間沖擊?？s短換檔時間，同時

46、防止嚙合時齒間沖擊。 2、構造：、構造： 結合套、花鍵榖、對應齒輪上的結合齒圈、結合套、花鍵榖、對應齒輪上的結合齒圈、同步裝置、鎖止裝置。同步裝置、鎖止裝置。 3、同步器分類：、同步器分類： 常壓式、慣性式、自增力式常壓式、慣性式、自增力式 慣性式同步器分類：慣性式同步器分類：鎖環(huán)式慣性同步器鎖環(huán)式慣性同步器 鎖銷式慣性同步器鎖銷式慣性同步器1.鎖環(huán)式慣性同步器sintanrfRr為鎖止面平均半徑；為鎖止面鎖止角;R摩擦錐面平均半徑; 錐面半錐角鎖環(huán)式慣性同步器鎖環(huán)式慣性同步器細牙螺旋槽滑塊構造滑塊鎖環(huán)結合齒圈原理原理定位銷、滑塊鎖環(huán)結合齒圈1齒厚2. 鎖銷式慣性同步器鎖銷式慣性同步器摩擦錐盤

47、摩擦錐環(huán)定位銷結合套鋼球定位銷鎖銷直徑較大的摩擦錐面，可產(chǎn)生較大摩擦力矩縮短同步時間。鎖銷受力鎖銷受力鎖止角Synchronizer OperationSynchronizersThis 5-speed transaxle has 3 synchronizer assemblies. Each one has a neutral and two other gear positions.3-4 Synchro. Assembly1-2 Synchro. Assembly5-Rev Synchro. AssemblySynchronizer ComponentsInput Shaft3-4 Sy

48、nchro.Blocker RingsSpeed Gears with Needle BearingsThe hub of this 3-4 synchronizer is splined onto the input shaft The 3rd and 4th speed gears fit over the needle bearings and the input shaft. This input shaft also has driving gears for 1st, 2nd, and reverse.Synchronizer Assembly, Exploded ViewThis

49、 synchronizer assembly has been taken apart to show the major parts. Most synchronizers have 3 or 4 struts.Energizer SpringsHubSleeveKey/Strut/InsertSynchronizer HubThe keys (green) and energizer springs (red) fit into the hub so the springs will exert an outward pressure on the keys. Note the splin

50、es on the inside of the hub to connect with the shaft.Synchronizer Assembly, Assembled ViewThe sleeve (orange) can slide on the hub (grey). The keys (green) are pushed outward, against the sleeve by the energizer springs (red).Synchronizer SleeveTwo important features of a synchronizer sleeve are th

51、e neutral detent notch around the center of the splines and the spline lock back taper at the ends of each spline. The neutral detent notch engages the hump on the keys. A complete shift places the back taper along side of the clutch teeth back taper.Back TaperNeutral Detent NotchSpeed GearsA speed

52、gear has teeth (blue) that drive or are driven by another gear. It also has clutching teeth (green) that engage the synchronizer sleeve, a smooth cone surface (orange) for the blocker ring, and a smooth inner bore (yellow) for the gear to rotate on.Clutching TeethConeBlocker RingsA blocker ring is a

53、lso called a synchronizer ring or stop ring. A 1-piece, metal blocker ring is used in most older transmissions. Note the grooves (circled) and threads on the inner surface to remove the lubricant from the speed gear cone. The blocker ring floats in the synchronizer assembly and is driven by the keys

54、, positioned in the three notches (red, triple arrow).3-Piece Blocker RingsOuter Blocker RingIntermediate ConeSpeed GearInner Blocker RingSome modern transmissions use paper-lined blocker rings for better shifting. These are 3-piece units. The inner and outer blocker rings are attached to each other

55、 and the synchronizer. The intermediate cone is attached to the speed gear. These transmissions usually require a special lubricant.Blocker Ring OperationWhen the sleeve is shifted to the left, the key will move with it. After a small amount of movement, the key will push the blocker ring against th

56、e speed gear cone, and the blocker ring will try to rotate with the speed gear. Note how much bigger the blocker ring notch is than the key; this allows the key to rotate slightly to block the sleeve.Speed GearSleeve Blocker RingKeyHubEnergizer SpringOperation During ShiftSpeed Gear TravelSleeve Spl

57、ine MovementBlocker Ring MovementSleeve movement at the beginning of a shift, moves the blocker ring to contact the speed gear cone. The blocker ring then rotates slightly so its teeth are blocking the splines in the sleeve. Further shift pressure pushes the blocker ring against the speed gear cone.

58、 This slows the speed gear to the same speed as the synchronizer.Completed ShiftAfter the speed gear slows down, the blocker rings moves aside, and the sleeve can move over the clutch teeth. The shift is complete when the back tapers are side by side as shown in the center.Speed GearSleeveBack Taper

59、sClutching TeethBack TaperThis section of a speed gear shows how the back side of the clutching teeth (light blue) are tapered to become narrower. This taper holds the synchronizer sleeve in place and prevents gear “jump out”.第四節(jié)第四節(jié) 變速器操縱機構變速器操縱機構n功用：功用： n保證駕駛員能準確可靠地使變速器換入某個檔位。保證駕駛員能準確可靠地使變速器換入某個檔位。

60、 n要求：要求： n自鎖功能：防止自動換檔、脫檔。自鎖功能：防止自動換檔、脫檔。 n互鎖功能：保證變速器不會同時換入兩個檔位?；ユi功能：保證變速器不會同時換入兩個檔位。 n倒檔鎖：防止誤換倒檔。倒檔鎖：防止誤換倒檔。 n分類：分類： n直接操縱式直接操縱式 n遠距離操縱式遠距離操縱式Shifting GearsMost SUV and pickup transmissions incorporate the shift mechanism into the the top of the unit. Movement of the gear shit lever will move one of the shift forks c