分动箱-外文文献

The so-called transfer case, is the power of the engine for the distribution, output to front axle and rear axle respectively of the device. From this point of view can see, transfer case is actually the raider buggies a accessories. Along with the raider buggies technology development, the transfer case also has been the change, and gradually form the style different transfer case, matching the raider is in different appeal, their basic principle and function are also different. The first raider technology, is based on the improve vehicle through sexual development, we called it the cross-country raider buggies. This kind of car is the ancestor of the second world war, American troops Willis jeep in order to strengthen the front line infantry and commander of the development of mobility out of combat. It used Transfer case is the most basic points raider Transfer case, is a pure mechanical device.The structure of the Transfer case, hang up the 4 flooding patterns, rear axle is before the rigid connection, may realize the power 50: the before and after 50 distribution, to improve the vehicles through sexual very favorable. Plus, because it purely mechanical structure, high reliability, this to often lack the wilderness in rescue vehicles driving is very important. Even now, there are still a lot of hard sent by theTransfer case suv, is based on the characteristics of it. Let's take a look at this Transfer case basic principle and structure.In this kind of car Transfer case on the block, we will see 2H,4H,N and 4L switching gears. When hang 2H, such models is a whip, the power of the engine driving after gearbox, through a shaft after root connected directly to the rear axle. And Transfer case role, which is in the gearbox, and then lead to an output terminal, and through the mute chain, will power transfer to the front axle output shaft. Of course, this is not to direct connection, it will not switch 4 flooding and 2 flooding. In fact, it is through the two groups of gear separated and connection of the structure and principle, it is similar to the one axis, and two transmission shaft. When switching Transfer case throw of the block, through the fork will power and transmission through and disconnect before. And now the mainstream with synchronizer gearbox, the part of the different switching is no synchronizer, it needs the wheel speed and the match. This is the Transfer case basic principle.But the truth is not so simple, in order to improve the performance of this kind of Transfer case through, there will still be one block, also is the strength of the block on 4L model. In the gearbox, more than the gear tooth, when hung up the gear, can provide a much higher than daily driving the main transmission. We found that when we need to hang 4L, must go through a N block, at this time will power and each transmission shaft separated, and hang up 4L, will be through to this tooth more than the gear. The switch of the process, is also no synchronizer. Know the principle, we take a look at this Transfer case each mode of operation characteristics. Familiar with traditional suvs, having know this Transfer case, in 2H and 4H, we do not need to switch between parking, can generally in the 80 km/hour per hour free switch. And switch to 2L, it must stop switch, or fundamental hang in, is this why? Whether 2H mode or 4H mode, the power is always connected with rear-axle, the rear wheels wheel and engine speed completely match. But at this time as long as no sliding, front wheel and rear wheel speed is same, so in 2H and 4H switch between, engine speed and output shaft speed is before the match, even without synchronizer, also can switch. So in 2H mode and 4H mode, can switch between the onboard, need not stop switch. But in the 4L mode switch, it was completely different. From 4H switch to 4L model, need to add Transfer case switch for N block, this time of engine power and each wheel are disconnected, engine to idling process. If this time the wheels of L, hang 4 wheel and the speed of the engine can be hard to match, equivalent to a without synchronizer driving process want to hang a block, this is clearly a very difficult. This Transfer case between front axle is not between the differential, therefore in the high adhesion of the ROAD can only hang 2H, 4 flooding mode is only in the gravel ROAD and OFF ROAD sections to improve-through sexual and design. So the method of this Transfer case buggies are generally hard-line rovers, it in the OFF-ROAD sections it bad, but in the highway is average performance. The early time, is totally by manual raider switch, later, there was electric switch points raider buggies, it the basic principles and manual switching points raider is same, but all of the switch is through the motor to complete it. 1.Transfer case full-time raider buggies With the development of the technology of raider buggies, people are not satisfied with just four drove cross-country only. In the highway, the raider buggies technology vehicles can offer a better driving force and control performance, so full-time raider was born. Hard shaft link of raider buggies can't achieve highway raider driving the main reason, is it not in freeway turn. Because in when turning, each wheel crushes the arc length different, this means that each of the wheel speed are not the same. In fact, the speed of the front wheel is will be higher than the rear wheels, if the rigid to the power of the engine through the drive shaft before and after assigned to the wheel, then the before and after the wheel speed must be consistent, the contradiction between before and after the steering wheel will lead to occur to interfere. The adhesion of sand of pavement in low by the sliding friction tires and the ground, and in dry pavement solution will produce a braking, let the car won't go forward, this is we often say to brake. In order to resolve the contradiction, the engineer in thansfer joined the a differential, this is we are now often say the central differential. The differential is open differentials, structure and the differential between front axle, as well as the output shaft transmission through planetary gear set will power distribution to rear axle before. According to the principle of differential open mode, it can adjust the speed difference. This structure is even full-time raider? The prototype of the early full-time raider is really such, but we will find, the raider buggies to improve the system through sexual makes no sense. We know, open mode is the function of differential the engine power distribution to the small resistance wheels, if a car use of three open differential (between front axle and a differential) each to adjust the speed difference of words, so if there is a wheel has the least resistance, by motivation to transfer to the wheels by 100%. Obviously this raider is pointless. In order to solve this problem, different engineer USES two different project.One is the differential limit. We already know, open mode will be passed to the power differential resistance smaller wheels, by that if we give the car a resistance on human nature, the power can be passed to the no sliding (there are still grip the wheels of). Its basic structure is a kind of similar to the device, but it clutch many groups, we called it the multi-gear clutch type differential limit device. In the differential shell and two output shaft each have a set of pieces of steel, their mutual crisscross, normally between each other is separated. If the front wheels skid, it will front axle and the pressure and the clutch disc, which will power transfer to the rear wheels more, rear wheel slippage, the truth is the same. This is the type of differential limit has a lot of, have through the silicone oil of the realization of the mechanical (about the principle of silicone oil after described the) and through the electronic control of electronic electrical switching of the clutch. In the more upscale cars, it is not only the differential limit solution to the wheel slippage problem, still can have the initiative of the power distribution function, can even realize the power from 0 to 100% in the first free distribution between rear axles.Another is the central differential lock. It actually is equivalent to need to improve through the sex, can be hard to realize between front axle shaft link, power, according to 50 50 assigned to rear axle before. Its basic structure is in between, between front axle with friction, the current round of steel or rear wheels skid, mechanical device will through the electromagnetic valve control of both a bite to realize the fixed, 50 50 power distribution. There is a full-time raider buggies, that is the thansfer structure of the famous audi QUATTRO. It is mainly through the worm planetary gear to achieve, structure is complex, here no longer expatiatory.This structure can solve the problem of poor speed, plays the role of open differential, at the same time can automatically will power distribution to the resistance of the biggest problems that have the function of the differential limit. It can achieve 25%-75% of power between free distribution, and all this is through the core of it, to realize the differential's, more magical is, the "spider's without the use of any electromagnetic device that is pure mechanical. No matter how advanced electronic equipment are lags in response problem so and other manufacturers of technical, compared the purely mechanical QUATTRO in velocity response is no one can and. Of course it has drawbacks-structure is complex, cost is high, power transmission loss is it could not cross the shortcomings. And full-time raider matching and electronic differential braking, is mainly used to adjust or so the wheel speed difference, before the lock and differential equivalent after differential lock. And the differential limit, compared the energy loss is bigger, generally do not to realize the wheels of before and after power distribution. 2.The raider Transfer case timely After that, some manufacturer's engineers found that not all need raider system of the road, for example in the normal cruising highway driving, only through the two wheel drive was completely can meet all driving demand. If this time still use a full-time raider buggies, neither economy, also don't have to. Therefore, in most cases only two wheel drive, and when necessary to be automatic into the raider buggies timely raider was born. Timely raider buggies also have two solutions, one with Honda CR-V, as a representative of the cohesive shaft quarter even through implementation; A is above generation of 4 MATIC-as a representative of the through the multi-gear clutch realized. Although they can achieve normal when two wheel drive, the drive wheels skid automatically through the effect of raider buggies, but yet there are differences between the structure and function. CR-V as a representative of this kind of timely raider Transfer case structure most simple, it is based on the horizontal buy before the engine front wheel drive technology platform, in two aspects, and flooding the car platform is exactly the same as before. On this basis, the engineer in the gearbox brings the root to rear axle output shaft, and driving axle differential between, use the cohesive shaft quarter even connection. Even in the shaft section is filled with silicone oil, it is characteristic of temperature rise will also rise after viscosity. Even the axis of the festival in output and input, are equipped with a blade, similar to the hydraulic torque converter structure. When moving the nose wheel is not skid, there is no round between the control speed difference, the cohesive shaft in the quarter even two shaft between each other is no speed difference. At this time is not passed to power the rear axle. The current round of sliding, the speed of the front wheel will be greater than the rear wheels, even at this time of day cohesive shaft input speed will more than the output, as hydraulic torque converter general, able to power transfer to rear axle. Not only that, because the rotation speed difference can cause heating up and become viscous silicon oil, so as to further increase the power of transmission, rear wheel drive. Through this structure, we will find that the response speed, it is more slowly, and power transfer is limited, and it is difficult to will be 50% of power distribution to rear axle. But its simple structure, low cost, for city road driving to the SUV, it can meet the basic needs. A generation 4 MATIC-as a representative of the timely Transfer case raider buggies, structure than even shaft section of the sticky timely raider is more complicated, and the above the central differential lock some similar, it is through the electromagnetic clutch to realize the raider buggies. It is also based on two flooding platform is developed, the raider buggies system in one end of the transmission in the basin type gear shaft brings the root will power transfer to front wheel, by connection between multi-gear clutch. It's connected to the broken and principle and said before the central differential lock principle similar, there is no redundancy. Its advantage is than full-time raider simple structure, response speed and power distribution cohesive shaft is better than even section. Along with the structure of the raider buggies the further development of technology, and now some of the vehicles already made the power of the free distribution, a lot of official propaganda the raider buggies also known as full-time raider buggies, in fact is not accurate. And is equipped with central differential locks, compared to the real full-time raider buggies on multi-gear clutch realize power distribution of so-called full-time raider buggies, only 50% of the power distribution, and give the driven pulley in turning power distribution, cannot reach the level of the raider buggies full-time real. In essence, this kind of raider buggies still can only be called a timely, for example the public want unless 4-amount. 3.Super choose Transfer case raider buggies This call is the mitsubishi, long can also be seen as mitsubishi special technology. From the Transfer case block to see, it is more like traditional timeshare raider system, which differs is, it is equipped with central differential. When hung up 4H, not only in ShaShiLu face high-speed, also can be in ordinary highway to realize the function of the raider buggies highway. And it provides four HLC and 4LLC options, is locked the central differential lock mode of raider buggies, at this time, it and points of raider buggies 4H and 4L function is the same. Mitsubishi is called super choose, in fact because than all the raider buggies system can the scope of the choice. The general full-time buggies, can only choose raider is traveling in don't need raider buggies, this way clearly not economy; And timely raider although can realize two flooding, but in the raider can not reach the real full-time raider performance; Raider points need not say, it completely unable to realize highway raider buggies to drive. And all these, super choose raider buggies can choose-want to economical, he hung up 2H, want to road full-time raider buggies will hang up 4H, want to achieve and traditional points of the same sex, the raider buggies will hang up 4HLC or 4LLC.