變速器及操縱機構設計-3

變速器及操縱機構設計-3,變速器,操縱,機構,設計 車輛與動力工程學院畢業(yè)設計說明書The NV4500 five-speed transmission in our high-mileage diesel-powered 95 Chevy 2500 pickup was exhibiting some bad behavior. Part of the problem was that the clutch wasnt releasing completely when the clutch pedal was depressed. This made selecting First Gear a grinding challenge. Eventually, the main driver of this rig quit using the clutch during standard gearshifts because it wasnt disengaging anyway. Another problem was that as the transmission began to age, it began to leak. In a pinch, someone ignored the requirement of Castrol Syntorq LT synthetic oil (or equivalent) and fed it petroleum-based oil. Things quickly went from bad to worse as the synchronizer rings objected to the wrong oil. It wasnt long before the trans was becoming very hard to live with.Since were not manual-transmission rebuild experts, we took the truck to someone who is. Larrys Automotive is located on the outskirts of Rock City, Illinois. The owner, Rick Jacobson, has been wrenching on trucks and cars since he was 12 years old, so he knows his stuff. His knowledge is vast and varied, and his resume includes a couple of years fabricating and wrenching for noted off-road racer Scott Taylor. Jacobson and his team of technicians not only have a working knowledge of vehicles (including heavy trucks) from end to end, they also know the intricate workings of both automatic and manual transmissions. Best of all, Jacobson is a wheeler, so hes intimately familiar with how we use our rigs.Jacobson and his crew removed our crusty trans and then they totally disassembled it and gave us the tally of what bad things were lurking inside. The list of parts we needed was lengthy. Normally, theyd just order the parts and complete the rebuild in a few days, but we wanted to utilize specific companies, so we hit the phone.The first place we called was Rockland Standard Gear. RSG, as theyre called, has been in business for more than 25 years, and theyre one of the largest suppliers of manual transmission and transfer-case parts in the country. Heres some mind-boggling facts: They are the only aftermarket company ever selected to rebuild transmissions for ZF; they are one of five Master distributors for Borg-Warner transfer-case parts; they are one of 10 Elite distributors for Tremec; and they are a major distributor for New Venture Gear. Needless to say, we knew they could handle our NV4500 needs.Since were not manual-transmission rebuild experts, we took the truck to someone who is. Larrys Automotive is located on the outskirts of Rock City, Illinois. The owner, Rick Jacobson, has been wrenching on trucks and cars since he was 12 years old, so he knows his stuff. His knowledge is vast and varied, and his resume includes a couple of years fabricating and wrenching for noted off-road racer Scott Taylor. Jacobson and his team of technicians not only have a working knowledge of vehicles (including heavy trucks) from end to end, they also know the intricate workings of both automatic and manual transmissions. Best of all, Jacobson is a wheeler, so hes intimately familiar with how we use our rigs.Jacobson and his crew removed our crusty trans and then they totally disassembled it and gave us the tally of what bad things were lurking inside. The list of parts we needed was lengthy. Normally, theyd just order the parts and complete the rebuild in a few days, but we wanted to utilize specific companies, so we hit the phone.The first place we called was Rockland Standard Gear. RSG, as theyre called, has been in business for more than 25 years, and theyre one of the largest suppliers of manual transmission and transfer-case parts in the country. Heres some mind-boggling facts: They are the only aftermarket company ever selected to rebuild transmissions for ZF; they are one of five Master distributors for Borg-Warner transfer-case parts; they are one of 10 Elite distributors for Tremec; and they are a major distributor for New Venture Gear. Needless to say, we knew they could handle our NV4500 needs.Since the clutch in our Chevy was original, our second call was to Center force. The company has been around since the early 80s and was started by Bill Hays, the founder of Hays Clutches in the 1950s. Bill Hays designed and patented the Center force Weighted Clutch System, which increases pressure-plate clamping force while maintaining easy pedal effort. Further, his new design solved the sticking-over-center problem of diaphragm clutches. Centerforce offers a full range of clutches and flywheels for a number of applications.What follows is a synopsis of the major items addressed by the team at Larrys Automotive. Itll give you a good idea of what you can expect if you plan on having your NV4500 rebuilt. Heres our Larrys Automotive-rebuilt trans ready to reinstall in our Chevy pickup. The folks at RSG note that one of the important things to remember about the NV4500 is that it requires Castrol Syntorq LT synthetic oil (or equivalent-RSG has an equivalent that they sell under their own brand name) due to the synchronizer material and design, as well as the large amount of gear teeth in mesh in this unit. Using standard gear oil will cause the NV4500 to shift poorly and eventually fail.Our input shaft (left) was showing significant wear at the point where the pilot bearing contacted the shaft, so we installed a new shaft from RSG. Jacobson always inspects the entire shaft for any signs of wear. Surprisingly, the gear on the other end (which is actually Fourth Gear) was in pretty good shapeOn the left you can see our old synchro ring for the Third to Fourth gearshift, pictured next to the new RSG synchro ring. All synchro rings are a common wear item on manual transmissions. When these wear, they basically lose friction and the result is grinding when shifting. All of our synchros were toast, so they were replaced with new units from RSG. The NV4500 uses two kinds of synchros: multi-piece and single-piece.This is our Second Gear (left) pictured next to our new RSG Second Gear. Jacobson found that the drive ring on the First to Second Gear single-piece synchro was worn into the teeth on Second Gear. Also, where the shift collar engages into the teeth of the gear, the teeth were chipped. This was most likely due to forcing the unit into gear before the synchro had caught up to the gear5 Here you can see Fifth Gear. Our old one is on the left and the new RSG unit is on the right. Ours clearly showed wear from pulling heavy loads. The hard surface was worn off the teeth and the inside splines also showed wear.On the left you can see an example of a tapered roller bearing that we removed from our trans. These are critical components that must be inspected, but they dont always need to be replaced. All of our bearings, with the exception of the caged needle bearings, showed gray areas indicating wear, as well as pitting. New tapered roller bearings were included in RSGs Bearing and Seal kit.RSG sent us a remanufactured shift tower (right). Our shift forks showed a lot of wear, which often results in them not engaging the shift collar far enough into the gear. This can cause the trans to pop out of gear. Jacobson normally inspects the shift tower for a variety of wear items that can make a trans operate poorly.This is the front bearing retainer, which holds the front main bearing in, and its what the throwout bearing rides on. After a thorough inspection, Jacobson gave ours a clean bill of health. After inspecting the bearing surfaces, splines, and Fifth Gear nut retaining threads, Jacobson also found that our mainshaft was in great shape. As we started reassembling our trans, Jacobson pointed out that all new items such as snap rings are included in the RSG small parts kit and they must be installed. Here you can see the shaft with First and Second Gear and other components installed. Jacobson is installing the pin that locks in a thrust washer. Part of its duties include keeping Second Gear from turning against Third Gear. There are three pins like this in the NV4500.Here you can see the mainshaft with everything mocked up but without the bearings pressed on in their finished position. During reassembly, Jacobson says its important to ensure that the synchros and slide collars arent installed backwards. All transmissions, especially the NV3500, will have all kinds of issues if these parts are reassembled incorrectly12 Surprisingly, our countershaft was in good shape. We just installed a new bearing and overdrive synchro ring. This shaft carries a load in all gears except Fourth Gear (Fourth Gear is the 1.00:1 gear, so it doesnt route power through the countershaft)Its important to correctly install the rear bearing retainer (shown), because it also holds the reverse idler gearshaft in place. If the reverse idler gearshaft is incorrectly installed, you can bend the bearing retainer and even possibly crack the transmission case.These shims go between the rear bearing retainer and the bearing to provide proper endplay for the mainshaft (the countershaft also uses shims to set endplay). After installing new bearings, the endplay may change, so endplay must be measured with a dial indicator. New shims are included in the RSG small parts kit.Here you can see our dual mass flywheel after it was resurfaced. Before it was sent out, Jacobson gave it a thorough inspection that included looking for heat cracks and inspecting the springs to make sure they were intact and in good shape. Overall, our flywheel was in good shape, especially considering the high mileage and abuse it has endured.With almost 100,000 miles on the odometer, it came as no surprise that out factory clutch was shot, so we installed a new Centerforce Dual Friction clutch assembly. This bad boy generates up to a 90 percent increase in holding capacity over the stock clutch. Even with this vastly increased holding capacity, it provides smooth engagement and light pedal pressure. Centerforce also sent a clutch pilot tool and a clutch release (throwout) bearing.The technicians at Larrys Automotive did battle with our pilot bearing in an effort to remove it from the engine block. Part of the problem was that the input shaft had severely worn the pilot bearing, so there was little for the puller to latch onto. This is a common issue with high-mileage manual-transmission vehiclesFluid leakage and a dragging clutch forced us to install a new clutch slave. The leakage problem was solved, but not the dragging. Jacobson and his crew ended up lengthening the stock clutch linkage by about 0.25 inch to effectively raise the clutch pedal from the floor when depressed. This allowed the clutch to totally disengageA busy shop and our tight deadlines meant we had to install the trans old-school without the truck on a hoist. First, the clutch and bellhousing were installed, then the trans, and then the transfer case and driveshafts. Our first drive revealed a perfect shifting transmission, and thanks to the creativity of the guys at Larrys Automotive, we no longer have a dragging clutchFifth Gear And The Dodge NV4500.Having problems with Fifth Gear in your Dodge NV4500? There is a fix. According to the folks at Rockland Standard Gear, the Dodge NV4500 had a design defect in the splines on the mainshaft Fifth Gear. The splines were not long enough and they were manufactured with an incorrect angle. This caused a slight creep of the Fifth Gear on the mainshaft due to throttle changes, which resulted in many of the units having the Fifth Gear loosen its retaining nut. This allowed the gear to move out of position on the mainshaft and cease to function. If you have a Dodge NV4500 with this problem, you have options. One is to purchase the kit that RSG offers. It includes a gear and mainshaft that utilize split-ring washers under a locknut to retain the gear under thrust loads. It also has redesigned full-length splines on the gear and corrected spline angles.NV公司5速傳輸在我們的高里程柴油動力95雪佛蘭2500皮卡中顯露出一些不良性能。部分4500存在當離合器踏板被壓抑時離合器不能完全釋放的問題。這就出現(xiàn)了要選擇第一齒輪磨床的挑戰(zhàn)。最終，這種鉆機退出的主要驅動力是使用裝在標準齒輪之間的離合器，因為它無論如何都不會脫離。另一個問題是當傳輸時間變長就會開始泄漏。在一個夾送，有人無視Castrol Syntorq審裁處合成油和美聯(lián)儲它以石油為基礎的石油的規(guī)定。事情很快變得更糟糕，作為同步器戒指反對錯了油。 因為我們還沒有手動傳動重建專家，我們選擇了適當?shù)娜诉x去做。拉里汽車是坐落于郊區(qū)的巖城，伊利諾州。它的所有人是里克雅各布森，在他12歲的時候就一直沉浸在卡車和汽車里，所以他了解他所擁有的。他擁有豐富的和廣泛的知識，他的重新開始包括兩年的改造和離道車手斯科特泰勒。雅各布森和他的團隊的技術不僅對車輛（包括重型卡車）有頭至尾的操作知識，他們也知道關于自動和手動變速器的錯綜復雜的運作。最重要的是，雅各布森是一個創(chuàng)始者，所以他很熟悉我們是如何使用我們的裝備。雅各布森和他的機組人員刪除我們的，然后他們把它完全拆解，并給我們所有潛伏在其中的不好的方面的總數(shù)。名單中的一部分方面我們需要漫長的時間去解決。通常，他們只要求這部分可以在數(shù)天內完成重建，但我們想要利用特定的公司，所以我們要找到解決的途徑。 放在首位的是我們所謂的羅克蘭標準齒輪。正如薪酬研究小組所稱的，它已在業(yè)務中存在了至少25年，他們是最大的手動變速器的供應商之一，并可以在國內進行轉移。這里有一些想法驚人的事實：他們是唯一的售后公司始終都選定重建的變速器ZF ，他們是一對五的分銷商在博格-華納轉移的情況下，;他們是一對十的精英分銷商Tremec ;他們是一個主要的分銷商作為新企業(yè)的齒輪。不用說，我們知道他們可以處理我們對nv4500的需要。 由于離合器在我們的雪佛蘭是原生的，所以我們又稱它為第二個中心的力量。該公司從八十年代初期一致被關注，并由在20世紀50年代發(fā)現(xiàn)離合器的海斯創(chuàng)建。比爾海斯設計了加權離合器系統(tǒng)并獲得專利，該系統(tǒng)使壓力增加板的夾緊力增強，同時保持踏板的牢固。此外，他的新設計解決了膜片離合器超過中心的問題。第一個中心力量提供全套的離合器和飛輪為一申請數(shù)目。 以下概要的主要項目所涉及的是在拉里汽車的團隊。您可以預期如果您打算讓您的nv4500重建，它會給您一個好的建議。這里是我們的拉里的汽車重建跨準備重新安裝在我們的雪佛蘭皮卡。鄉(xiāng)親在薪酬研究小組注意到，其中一個重要的事情要記住有關nv4500的是，它需要castrol syntorq審裁處合成油（或同等學歷-薪酬研究小組有一個相等于他們下出售自己的品牌名稱） ，由于同步器材料和設計，以及大量的齒輪齒數(shù)在網(wǎng)格在這股。使用標準的齒輪油，會導致nv4500轉向不佳，并最終失敗。我們的輸入軸（左）表現(xiàn)出顯著的磨損點，試驗軸承接觸軸，所以我們安裝了一個新的軸從薪酬研究小組。雅各布森始終考察整個軸的任何跡象磨損。令人驚訝的是，對齒輪的另一端（其實是四檔）是非常好的表現(xiàn)在左邊你可以看到我們的老同步響第三至第四變速，照片旁邊的新的薪酬研究小組同步環(huán)。所有同步環(huán)是一種常見的磨損的項目手冊傳送的安全性。當這些磨損，他們基本上失去了摩擦和結果是磨削時移。我們所有的synchros分別致祝酒辭，所以他們更換新單位從薪酬研究小組。該nv4500使用兩種synchros ：多件;單件。這是我們的第二個齒輪（左）合照明年我們新的薪酬研究小組第二齒輪。雅各布森發(fā)現(xiàn)該驅動器響就第一項至第二齒輪單件同步被磨損到牙齒上第二個齒輪。此外，那里轉移到衣領從事牙齒的齒輪，牙齒插話。這是最有可能是由于迫使結合本單位的齒輪前同步已趕上了以齒輪在這里您可以看到第五齒輪。我們的老，一個是在左邊和新的薪酬研究小組的單位是正確的。我們清楚地表明，從磨損拉重物。硬表面磨損小康牙齒和內花鍵還表明，磨損。在左邊你可以看到一個例子，一個圓錐滾子軸承，我們從我們的轉運。這些都是關鍵部件必須檢查，但他們并不總是需要更換。我們所有的軸承，除籠針軸承，顯示灰色地帶，顯示磨損，以及孔蝕。新的圓錐滾子軸承被列入在薪酬研究小組的軸承和密封包。薪酬研究小組向我們發(fā)出一再造轉移塔（右） 。我們的轉移叉表明了很多磨損，這往往結果在他們不要從事轉移的衣領遠遠不夠成齒輪。這可能會導致跨到彈出的齒輪。雅各布森通?？疾斓霓D變，塔各種磨損的項目可以使一個跨經營不善。這是前軸承聘，擔任前線主軸承在，它的是什么throwout軸承游戲機上。經過徹底的檢查，雅各布森了我們一個清潔的條例草案的健康狀況。之后，檢查支座表面，樣條，第五齒輪螺母保留線程，雅各布森還發(fā)現(xiàn)，我們的主軸是在偉大的形狀。正如我們重新開始我們的轉運，雅各布森指出，所有新項目，如管理單元戒指，都包括在薪酬研究小組小零件和工具包，他們必須安裝。在這里您可以看到軸與第一和第二齒輪和其他組件安裝。雅各布森是安裝引腳，鎖在一個推力墊圈。的一部分，其職責包括保持第二齒輪從轉折對第三方的齒輪。有三個引腳一樣，在這方面nv4500 。這里，您可以看到主軸與一切嘲笑，但沒有軸承的壓力就在其完成的立場。在組裝，雅各布森說，它的重要性，以確保該synchros及幻燈片衣領未安裝倒退。一切播送行為，特別是nv3500 ，將有各種問題，如果這些零件重新不當奇怪的是，我們的countershaft是在良好的形狀。我們剛剛安裝了一個新的軸承和超載同步環(huán)。這軸進行了負荷在所有齒輪除四檔（四檔是1.00:1齒輪，因此它不路線的權力，通過countershaft ）它的重要性，正確安裝后軸承家臣（如圖所示） ，因為它也持相反的托輥gearshaft在的地方。如果反向托輥gearshaft是正確安裝，您可以彎曲軸承保持，甚至可能打擊傳輸?shù)那闆r。這些shims轉到之間的后方軸承保持和軸承，提供適當?shù)膃ndplay為主軸（ countershaft還利用shims設置endplay ） 。之后，安裝新的軸承， endplay可能會改變，因此， endplay必須加以衡量與撥號的指標。新shims都包括在薪酬研究小組小零件包。在這里您可以看到我們的雙質量飛輪后，這是重鋪。之前，它被送往指出，雅各布森了一個徹底的檢查，其中包括尋找熱和裂縫，檢查彈簧，以確保他們完整，在良好的形狀。整體來說，我們的飛輪是在良好的形狀，特別是考慮到高里程和濫用，它已經歷。幾乎十萬英里里程表，它并不令人感到意外指出，離合器廠拍攝，因此，我們安裝了一個新的第一力量中心雙摩擦離合器大會。這個壞小子的產生多達90 的增長，容納超過股票離合器。即使這大大增加了控股能力，它提供了平穩(wěn)的接觸和輕踏板的壓力。 第一力量中心也發(fā)出了一個離合器試驗工具和離合器釋放軸承。技術員在拉里的汽車沒有戰(zhàn)役與我們的飛行員，同時努力消除它從發(fā)動機缸體。部分問題是，該輸入軸已嚴重磨損試驗的影響，所以很少為牽引，以抓住。這是一個常見的問題與高里程手動傳動車輛腦脊液漏和一拖離合器強迫我們安裝一個新的離合器的奴隸。泄漏問題得到解決，而不是拖延。雅各布森和他的機組人員結束了延長股票離合器的聯(lián)系，約0.25英寸，有效地提高離合器踏板從地板時，沮喪。這使離合器完全脫鉤一個繁忙的商店和我們的時間緊迫，意味著我們已安裝的跨國“老學?！睕]有車就一啟閉機。第一，離合器和bellhousing安裝，然后跨，然后轉移和driveshafts案件。我們的第一個驅動器顯示，一個完美的換擋變速器，和感謝的創(chuàng)造力，球員在拉里汽車，我們不再有拖曳離合器第五齒輪和道奇nv4500在您的道奇nv4500存在第五齒輪的問題 ？這里有一個修補程序。依照民間的羅克蘭標準齒輪，道奇nv4500在主軸第五齒輪鍵槽的設計中存在缺陷。鍵槽沒有足夠的長而且他們制造的角度不正確。由于油門的變化引起了在主軸上的第五齒輪的輕微變化，造成許多的單位有五分之一齒輪放寬其保留螺母。這使齒輪遷出了對主軸的位置并停止運作。如果您的道奇nv4500存在這個問題，你有解決的方法。一種是購買工具包，薪酬研究小組提供。它包括一個齒輪和主軸，利用分裂環(huán)墊圈下固定螺帽保留齒輪下推力的負荷。另一種是經過重新設計的在齒輪上有完整長度和正確角度的鍵槽。- 9 -