機械設計制造及其自動化 外文翻譯 外文文獻 英文文獻 電力驅動橋說明書

Electric drive axle descriptionAbstract: An electric drive axle, which is located between and powers the left and right drive wheels of an automotive vehicle, includes an electric motor and left and right torque couplings. Torque developed by the motor transfers through the torque couplings to axle shafts which are connected to the drive wheels. Each torque coupling includes a magnetic particle clutch and a planetary set organized such that the current flowing through the electromagnet of the clutch controls the torque delivered through the coupler. The magnetic particle clutches also accommodate slippage so that the drive wheels may rotate at different angular velocities.BACKGROUND OF THE INVENTION This invention relates in general to automotive vehicles and, more particularly, to an electically-powered drive axle for an automotive vehicle. The typical automobile derives all the power required to propel it from an internal combustion engine which is coupled to left and right drive wheels through a transmission and differential. Indeed, the differential divides the torque produced by the engine evenly between the drive wheels to which it is coupled. Recently several automotive manufacturers have demonstrated an interest in automobiles that in one way or another utilize electric motors to propel the vehicles. But these vehicles still rely on differentials of conventional construction to divide torque between the left and right drive wheels and to accommodate variations in speed between the drive wheels, such as when the vehicle negotiates a turn. However, an equal division of torque between the drive wheels on each side of a differential is not always desirable. For example, if the traction available to one of the drive wheels is diminished, most of the torque should flow to the other drive wheel. Also in turns, handling improves if most of the torque flows to the drive wheel on the outside of the turn. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1 is a schematic view of an automotive vehicle provided with an electric drive axle constructed in accordance with an embodying the present invention;FIG. 2 is an end view of the vehicle cut away to show the electric drive axle; FIG. 3 is a sectional view of the drive axle; FIG. 4 is an enlarged sectional of one of the torque couplers in the drive axle; FIG. 5 is an end view of a vehicle provided with a modified electric drive axle; FIG. 6 is a sectional view of the modified electric drive axle. DETAIL DESCRIPTION OF THE INVENTION Referring now to the drawings, an automotive vehicle A (FIG. 1) has a left and right drive wheels 2 and 4, respectively, that are powered through an electric drive axle B. To this end, the vehicle A has a source 6 of electrical energy, which could be a generator powered by an internal combustion engine or a bank of batteries or even fuel cells. In any event, the energy source 6 and the drive axle B are mounted on a supporting structure 8, which could be a frame or a unified body, and the supporting structure 8 is in turn supported in part by the wheels 2 and 4. The drive axle B is coupled to the wheels 2 and 4 through left and right axle shafts 10 and 12. It is organized about an axis X and includes (FIG. 2) a housing 20, an electric motor 22, and left and right torque bias couplings 24 and 26, respectively. The motor 18 and couplings 24 and 26 are located within the housing 20. The motor 18, which is of the radial flux construction, includes (FIG. 3) a stator 30 which is mounted in the housing 20 in a fixed position around the axis X. It also includes a rotor 32 which is located within the stator 30 where it revolves about the axis X. The rotor 32 includes a motor shaft 34 which at its ends is supported in the housing 20 on antifriction bearing 36. The housing 20 also encloses the two torque couplings 24 and 26, each of which includes a drive hub 40, a magnetic particle clutch 42, a planetary gear set 44, and a drive flange 46. They too are organized along the axis X. The two drive hubs 40 are connected to the motor shaft 34 of the rotor 32 through splines or other devices which enable them to rotate with the shaft 34 and transfer torque from the rotor 32 to their respective torque couplings 24 and 26. Indeed, the two drive hubs 40 rotate in the bearings 36 and support the shaft 34 and likewise the rotor 32 on the bearings 36. The drive flanges 46 are for the most part located externally of the housing 20 and serve to couple their respective torque couplings 24 and 26 to the axle shafts 10 and 12. The drive hubs 40 function as torque input members, whereas the drive flanges 46 serve as torque output members. The clutch 42 for each torque coupling 24 and 26 includes (FIG. 4) an electromagnet 50 and an armature 52. Both are annular in configuration and are organized about the axis X. The armature 52 resides within the electromagnetic 50, with the two being separated by antifriction bearings to the maintain a uniform annular gap g between them. The gap g contains magnetic particles. In the absence of a magnetic field at the gap g, the magnet 50 and armature 52 can rotate, essentially freely with respect to each other. However, when an electrical current is directed through the magnet 52, torque applied to the magnet 52 will transfer to the armature 54. Some slippage between the two may and in most instances will occur. The magnet 50 around its periphery carries slip rings 56 which are wiped by brushes 58 fitted to the housing 20. The brushes 58 in turn are connected to a source of electrical energy, the potential of which may be varied to vary the current in the electromagnet 52 and the strength of the magnetic field it produces. This controls the torque transferred by the clutch 42. The electromagnet 50 of the clutch 42 is secured firmly to the flange of the drive hub 36 at that end of the motor shaft 34 nearest the coupling 24 or 26 of which the clutch 42 is a component. Thus, the electromagnet 52 rotates with the rotor 32 of the electric motor 32. Should the electromagnet 52 be energized, torque applied to the electromagnet 52 will transfer to the armature 54. The planetary set 44 for each torque coupling 24 and 26 includes (FIG. 4) a sun gear 64, a ring gear 66, and planet gears 68 located between and engaged with the sun and ring gears 64 and 66. In addition, it has a carrier 70 which establishes the axes about which the planet gears 68 rotate. The sun gear 64 lies along the axis X, its axis coinciding with the axis X. It is provided with a stub shaft 72 which projects into the armature 56 of the clutch 42, to which it is coupled through mating splines. The ring gear 66 is attached to the electromagnet 54 of the clutch 42 and to the flange on the drive hub 40 at the end of the motor shaft 34, so that the hub 36, the electromagnet 54, and the ring gear 66 rotate in unison about the axis X and at the same angular velocity. The carrier 70 has pins 74 which project into the planet gears 68, so that the planet gears 68, when they rotate, revolve about the pins 74. The pins 74 thus establish the axes of rotation for the planet gears 68. In addition, the carrier 70 has a spindle 76 which projects through the end of the housing 20 and there is fitted with the drive flange 46. The left axle shaft 10 is connected through a universal joint to the drive flange 46 for the left torque coupling 24, whereas the right axle shaft 12 is connected through another universal joint to the drive flange 46 of the right torque coupling 26. The motor 22 drives the two axle shafts 10 and 12 through their respective torque couplings 24 and 26. The magnetic particle clutches 24 and 26 control the distribution of torque to the two axle shafts 10 and 12. In the operation of the drive axle A, the electrical energy source 6 produces an electrical current which powers the motor 22, causing the rotor 32 and motor shaft 34 of the motor 22 to rotate about the axis X. The motor shaft 34 delivers the torque to the two torque couplings 24 and 26. In each torque coupling 24 and 26, torque from the motor 22 is applied through the hub 40 at that coupling 24 or 26 to the electromagnet 50 of the clutch 42 and to the ring gear 66 of the planetary set 44 simultaneously. Here the torque splits. Some of it passes from the ring gear 66 through the planetary gears 68 to the carrier 70 and thence to the drive flange 46 through the spindle 76. The remainder of the torque, assuming that the electromagnet 50 of the clutch 42 is energized, passes through the gap g to the armature 52 of the clutch 42. The armature 52 rotates and transfers the component of the torque passing through the clutch 42 to the sun gear 64 of the planetary set 44, inasmuch as the armature 52 and sun gear 64 are coupled through the stub shaft 72 of the latter. The sun gear 64 transfers the torque to the planet gears 68 where it combines with the torque transferred from the ring gear 66, so that the carrier 70 and the drive flange 78 see essentially the full torque applied at the hub 40. In other words, the torque flows through each torque coupling 24 and 26 in two paths-a mechanical path, including the ring gear 68, planet gears 68 and carrier 70, and a clutch path, including the electromagnet 50 and armature 52 of the clutch 42, and the sun gear 64, planet gears 68 and carrier 70, of the planetary set 44. Most of the torque transfers through the mechanical path, with the apportionment between the two paths depending on the gear ratio U between ring gear 66 and the sun gear 64. The higher the ratio, the less the amount of torque transferred through the clutch path. The relationship between the torque in the two paths may be expressed with a plot on Cartesian coordinates (FIG. 5). The arrangement is such that a small change in torque transferred through the clutch 42 results in a much greater change in torque transmitted through the coupling 24 or 26 of which the clutch 42 is a component, and the torque transmitted through the clutch 42 is dependent on the magnitude of the current passing through the electromagnet 50 of the clutch 42. The torque varies almost linearly with the current passing through the electromagnet 50. By controlling the current in the clutches 42 of the two torque couplings 24 and 26, the torque can be divided between the two drive wheels 2 and 4 to best accommodate the driving conditions under which the vehicle A operates. For example, if the vehicle A negotiates a left turn, particularly at higher speeds, more torque should be delivered the right drive wheel 2 than to the left drive wheel 4. The clutches 42 in the two torque couplings 24 and 26 are adjusted accordingly. To this end the vehicle A may be provided with accelerometers for determining lateral and longitudinal accelerations and yaw, and hence the severity of turns negotiated, as well as speed sensors for determining the velocities of the two axle shafts 10 and 12, preferably from the antilock braking system for the wheels 2 and 4. More sensors may determine the position of the steering wheel and the temperatures of the clutches 42 and of the wheel service brakes. These sensors produce signals which may be fed to a microprocessor in the vehicle, which microprocessor would determine the best apportionment of torque between the two driving wheels 2 and 4 and control the current in the clutches 42 of the two torque couplings 10 and 12 accordingly. A modified electric drive axle C (FIGS. 6 & 7) likewise distributes torque between the left and right drive wheels 2 and 4, apportioning it best to respond to the conditions under which the vehicle A operates. It includes (FIG. 7) an axial flux motor 84, a housing 86 in which the two torque couplings 24 and 26 are enclosed, and a right angle drive 88 located within the housing 86 between the motor 84 and the hubs 40 of the torque couplings 24 and 26. The motor 84 includes a stator 92 and a rotor 94, as well as a motor shaft 96 in which the rotor 94 is mounted. The shaft 96 rotates about an axis Y oriented at a right angle to the axis X. The right angle drive 88 includes a pinion shaft 100 which rotates in the housing 86 about the axis X on antifriction bearings 102. One end of the shaft 100 is connected to the motor shaft 94, while the other end has a beveled pinion 104 on it. In addition, the right angle drive 88 has a connecting shaft 106 which extends between the two hubs 40 and rotates about the axis X. Its ends are fitted to the two drive hubs 40 with mating splines, and the hubs 40 rotate in the housing 86 on bearings 36. The motor 84, when energized, applies torque to and rotates the pinion shaft 100. The pinion 104 at the end of the shaft 100 rotates the spur gear 108 which in turn rotates the connecting shaft 106 and the hubs 40 at the end of it. The hubs 40 deliver the torque to the torque couplings 24 and 26 which function as they do in the drive axle A. Other so-called "hook ups" are possible for the two torque couplings 24 and 26-one, for example, in which the armature 52 of the clutch 42 may be connected to the drive hub 40. Also the positions of the clutch 42 and 44 in each of the torque couplings 24 and 26 may be reversed, with the clutch 42 being connected to the drive flange 46.TABLE-US-00001 ELECTRIC DRIVE AXLE A automotive vehicle B electric drive axle C electric drive axle X axis 2 drive wheel 4 drive wheel 6 energy source 8 supporting structure 10 left axle shaft 12 right axle shaft 20 housing 22 motor 24 left torque coupling 26 right torque coupling 30 stator 32 rotor 34 shaft 36 bearings 40 drive hub 42 magnetic clutch 44 planetary set 46 drive flange 50 electromagnet 52 armature 54 bearings 56 slip rings 58 brushes 62 64 sun gear 66 ring gear 68 planet gears 70 carrier 72 stub shaft 74 pins 76 spindle 84 motor 86 housing 88 right angle drive 90 92 stator 94 rotor 96 motor shaft 100 pinion shaft 102 bearings 104 pinion 106 connecting shaft 108 spur gear 電力驅動橋說明書摘要：電動驅動橋一般是安裝在車輛的左右驅動輪之間，包括一個電機和左右聯(lián)軸器。扭矩通過聯(lián)軸器傳到與驅動輪相連的半軸。每個聯(lián)軸器包括一個磁粉離合器和一個行星組，所以通過調(diào)節(jié)離合器中的電磁體的電流就能控制經(jīng)過聯(lián)軸器傳遞的扭矩大小。磁粉離合器還能允許滑移，因此驅動輪能得到不同的角速度。發(fā)明背景這項發(fā)明一般和汽車，尤其是電驅動汽車有聯(lián)系。典型的汽車輸出所需要的能量是從內(nèi)燃機的做功通過差速器分至左右驅動輪。事實上，差速器把發(fā)動機的力矩平均分給了驅動輪，這對力矩是共軛的。最近幾次有汽車制造商對利用電機推進車輛感興趣。但是這些車輛的差速的實現(xiàn)仍然靠傳統(tǒng)的差速器將轉矩分至左右驅動輪，且能適應驅動輪的速度變化范圍小，例如，當車輛轉彎時。然而，能把扭矩平均分給驅動輪的差速器并不是一直我們所需要的產(chǎn)品。舉個例子，如果一個驅動輪的牽引扭矩降低，那么大部分的扭矩應該流向另一個驅動輪。還有在轉彎時，如果大部分的扭矩流向外側的驅動輪，那么應做改善處理。簡要介紹幾個圖紙的意見圖1是從一個原理的角度來展示電動汽車電驅動橋的發(fā)明；圖2是從車輛尾部的一個剖切面來展示電驅動橋；圖3表示的是驅動橋的分解圖；圖4是一個耦合器在驅動橋上的放大截面圖；圖5是改進的車輛驅動橋的的最終觀點；圖6是修改后的電驅動橋的局部觀點。詳細說明現(xiàn)在要提到一些些圖紙，一輛汽車A（圖1）有左右驅動輪2和4，分別通過電驅動橋B傳遞動力。為此，車輛A有一個電源裝置6，可以使用內(nèi)燃機或一組蓄電池甚至燃料電池給電機供電。在任何情況下，電源裝置6和驅動橋B是被支承在支護結構8上的，支護結構可以是一個框架或一個閥體，支護結構8是輪流支護在輪子2和4之間。驅動橋B通過左、右半軸10和12聯(lián)接到車輪2和4。他的結構包括一根軸X和一個橋殼20，左右轉矩分別被傳遞至聯(lián)軸器24和26。電機18和聯(lián)軸器24和26被安裝在橋殼20上。電機18的徑向結構包括（圖3）一個定子30，它是安裝在橋殼20的一個軸向固定位置。它也包括了在定子30里面圍繞軸X旋轉的轉子32。轉子32包括一個末端固定在位于橋殼20里滾動軸承36上的電機軸34。橋殼20也擁有兩個扭矩聯(lián)軸器24和26，它們每一個都包括一個驅動鼓40，一個磁粉離合器42，一組行星齒輪44，一個驅動器法蘭46。它們也沿著軸X分布。這兩個驅動鼓40通過花鍵或其他裝置聯(lián)接到轉子32上的電機軸34上，使他們與電機軸34共同旋轉并將扭矩從轉子32傳送到聯(lián)軸器24和26。而且，這兩個驅動鼓40也在軸承36上旋轉，并且軸承36支承著電機軸34，同也支承著轉子32。驅動法蘭46大多數(shù)是位于橋殼20的外部，從而將力矩作用于聯(lián)軸器24和26并分別作用到半軸10和12。驅動鼓40的功能是作為力矩輸入，然而驅動法蘭46則是作為力矩輸出。離合器42和力矩聯(lián)軸器24和26，包括（圖4）一個電磁體50和一個電樞52。兩者都是環(huán)型配置在軸X上的。電樞52位于電磁體50里面，二者是被抗磨軸承和環(huán)型均勻的間隙g給分開的。g的間隙含有磁粉顆粒。在g里無磁場時，電磁體50和電樞52可以旋轉，本質(zhì)上沒有聯(lián)系。然而，當電流定向的通過電磁體52，電磁體52上的轉矩會被轉移到電樞54上。在大多數(shù)情況下這兩者之間的一些滑移將要發(fā)生。電磁體50繞著安裝了電刷58的周邊滑環(huán)56進行調(diào)整到殼20。電刷58反過來被連接到一個電源，畫出了相應的電位變化，并可以根據(jù)不同的電流來做電磁體52的磁場強度的管理。通過離合器42控制轉矩的傳遞。離合器42中的電磁體50被離合器42的一個組件驅動法蘭固定在靠近聯(lián)軸器24和36的電機軸34的末端。因此，電磁體52的旋轉與轉子32同步。如果電磁鐵52被通電，那么電磁體52的轉矩被轉移到電樞54。每個聯(lián)軸器24和26中的行星組44包括（圖4）一個太陽輪64，一個齒圈66和處于兩者之間的行星齒輪68并且和太陽輪64、齒圈66嚙合。此外，它還有一個安置在行星齒輪中心軸的行星架70。太陽輪64躺在軸X上，它的軸正好與軸X重回。它有一個短軸77，通過外花鍵和離合器42的電樞56相連。齒圈66是連接到離合器42上的電磁體54，并且連接電機軸34末端的驅動法蘭40，所以，電磁體54和齒圈66在軸X上同步旋轉，并且保持同樣的角速度。行星架70有插腳74連接到行星齒輪68，所以，當行星齒輪68旋轉時，插腳74也跟著旋轉。插腳74在行星齒輪68中設立旋轉軸。此外，行星架70還有一個通過橋殼20末端和適合驅動法蘭46的主軸76。左半軸10通過一個萬向節(jié)到驅動法蘭46和左邊的聯(lián)軸器相連，而右半軸12通過另外一個萬向節(jié)到驅動法蘭46和右邊聯(lián)軸器26相連。電機22通過各自的聯(lián)軸器24和26驅動兩個半軸10和12。磁粉離合器24和26控制左右半軸10和12的力矩分布。在運行的驅動橋A中，電源裝置6提供電機22所需的電流，使電機22的轉子32和電機軸34繞軸X旋轉。電機軸34將力矩傳送到兩個聯(lián)軸器24和26。在每個聯(lián)軸器24和26上，力矩從運轉的電機22通過在聯(lián)軸器24和26上的鼓40傳到離合器42上的電磁體50，同時傳到行星齒輪44上的齒圈66。在這里扭矩被分開。一步份扭矩從齒圈66通過行星齒輪68傳到行星架70，并且從那里通過主軸76傳到驅動法蘭46。如果離合器42上的電磁體50是通電的，那么剩下的扭矩通過間隙g傳到離合器42上的電樞52。電樞52旋轉并且通過離合器42對行星組44的上的太陽輪64的作用改變扭矩，因為電樞52和太陽輪64是通過傳動軸的尾端相連接的。太陽輪64旋轉傳遞扭矩到行星齒輪68，在這里它將與齒圈66傳遞的扭矩相結合，所以行星架70和驅動法蘭78看起來在鼓40上作用了力矩。換句話說，力矩流向聯(lián)軸器24和26有兩條路徑，一條機械路徑，包括齒圈68、行星齒輪68和行星架70，一條離合器路徑包括電磁體50和離合器42上的電樞52，和行星組44上的太陽輪64、行星齒輪68和行星架70。大部分的力矩傳遞通過機械路徑，兩條路徑傳遞的力矩分配是靠齒圈66和太陽輪64的齒數(shù)比U決定的。比例越高，則越少的扭矩通過離合器路徑傳遞。扭矩在這兩條路徑間的關系可以用笛卡爾坐標表示（圖5）。在這種安排上，對通過離合器42傳遞的扭矩一個小的改變，將導致通過離合器42的組件聯(lián)軸器24和26傳遞的扭矩較大的變化，并且離合器42傳遞扭矩的大小取決于傳送離合器42上的電磁體50的電流的大小。當轉矩變化是，電流幾乎線性通過電磁體50。通過控制兩聯(lián)軸器24和26上的離合器42的電流，扭矩能以最佳條件被分配到運行車輛A的兩個驅動輪2和4上。例如，如果車輛A左轉彎時，特別是高速左轉彎時，比左驅動輪4更多的扭矩將被傳遞到右驅動輪2。因此兩個聯(lián)軸器24和26上的離合器42將有相應的調(diào)整。為此車輛A可以裝備加速度計來決定側面和縱向的加速度并做調(diào)整，所以調(diào)整的結果就是和速度傳感器一樣來決定兩個半軸10和12的轉速，因此更適用于車輪2和4的剎車系統(tǒng)。更多的傳感器能決定方向盤的位置以及離合器42和剎車系統(tǒng)的溫度。這些傳感器產(chǎn)生信號并將信號傳給車輛上的微處理器，微處理器將決定兩個驅動輪2和4之間的扭矩分配，因此來控制兩個聯(lián)軸器10和12上的離合器42。一種改進的電驅動橋C（圖6和7）同樣的也能在車輛A運轉的條件下按最佳比例分配左右驅動輪2和4之間的扭矩。它包括（圖7）一個軸向通量電機84和封閉在一個殼86里的兩個聯(lián)軸器24和26，以及一個位于橋殼86里在電機84和聯(lián)軸器24和26上的轂40之間的主傳動器88。電機84包括一個定子92和一個轉子94，以及安裝在轉子94上的電機軸96。電機軸96繞著軸Y旋轉朝著直角上的軸X。主傳動器88包括一個小齒輪軸100，它位于橋殼86里面在滾動軸承102上繞軸X旋轉。傳動軸100的一端和電機軸94連接，而另一端有一個斜齒輪104在上面。此外，主傳動器88和傳動軸106連接，傳動軸延伸在鼓40和旋轉軸X之間。傳動軸的末端用花鍵和兩個驅動鼓40配合連接，并且鼓40在橋殼86里面的軸承36上旋轉。最后，主傳動器88在聯(lián)軸器24上的轂36上裝有斜齒輪108。齒輪108和小齒輪104嚙合。當電機84通電，將扭矩傳遞個小齒輪100。在傳動軸100末端的小齒輪104繞著斜齒輪108旋轉，斜齒輪旋轉連接傳動軸106和鼓40的末端。鼓40傳遞扭矩到聯(lián)軸器24和26，這是它在驅動橋A中的功用。對于兩個聯(lián)軸器24和26來說，其他所謂的“環(huán)環(huán)相扣”是可能的，例如，離合器42上的電樞52可能與驅動鼓40有聯(lián)系。同樣由于離合器42被連接到驅動法蘭46，離合器42和44在每個聯(lián)軸器24和26中的位置也可以顛倒。TABLE-US-00001電驅動橋：A-汽車 B-電驅動橋 C-電驅動橋 X-軸 2-驅動輪 4-驅動輪 6-電源 8-支撐架 10-左半軸 12-右半軸 20-橋殼 22-電機 24-左聯(lián)軸器 26-右聯(lián)軸器 30-定子 32-轉子 34-傳動軸 36-軸承 40-驅動鼓 42-磁粉離合器 44-行星組 46-驅動法蘭 50-電磁體 52-電樞 54-軸承 56-滑環(huán) 58-電刷 62、64-太陽輪 66-齒圈 68-行星齒輪 70-行星架 72-外半軸 74-插腳 76-主軸 84-電動機 86-橋殼 88-主傳動器 90、92-定子 94-轉子 96-電機軸 100-小齒輪軸 102-軸承 104-小齒輪 106-聯(lián)接軸 108-直齒輪