主题：说几种中古坦克的散热 -- epimetheus

简单讲讲上个月那次当傻逼吧。根源，还是不少老兄拿着维基上的知识当真理，而实际上维基很呵呵。所以就写了这么个维基的纠错。关键重点，就是有人不懂还拿着“再生”两个字装逼

我也是闲的无聊，西西河又没人和我聊这个

坦克的转向系统，令坦克或是别的“连续轨道车辆”能够转向。由于履带不能相对于车体发生转动（几乎所有的实用的设计都是如此，尽管曾经存在过可转向的前置第三履带），转向需要通过令一侧履带加速、另一侧履带减速、或是同时两侧分别加速减速（有单纯加速的么？）半履带车辆不用这样，有可以转向的轮子实现转向，并使用定速的履带（并不是定速，绝大多数半履带车使用被动自适应的差速器例如美国M3系列，另有少量能主动产生履带的速度差，例如德国Sdkfz251系列、美英仿制Sdkfz的某个原型车）

Early steering systems were adopted from tracked work vehicles, generally using a clutch to reduce power to one track, causing it to slow down. These designs have numerous problems, notably when climbing hills or running at high speed, as the reduction in power causes the overall speed to slow. Delivering power to both tracks while turning them at different speeds is a difficult design problem.

早期转向系统来自于履带工程车辆，通过离合器将一侧履带同动力断开，令其减速。这样的设计有着很多问题，尤其是在上坡或是高速下，因为会有整车速度的下降（真正的问题是需要制动增加阻力，仅仅通过离合器、履带滚动阻力无法有效控制转向，而车速下将反而不是重要的）。转向中同时向两个履带以不同的速度输出动力是个难题（实际情况，更多的条件下也不是“输出”动力，而是回收动力。除非是想要在极低速度下进行转向，就像工程车辆一样）

A series of more advanced designs were introduced, especially through World War II, that maintained power to both tracks during steering, a concept known as regenerative steering. Some also allowed one track to move forward while the other reversed, allowing the tank to spin in place, a concept known as neutral steering. The first really successful system was the British double differential design of 1924, which was copied by both the United States and Germany.

逐渐出现了一系列更加高级的转向系统设计，尤其是在二战时代，转向中能够同时向两侧履带同时输出动力，于是出现了一个新的概念“再生转向”。（再次强调，往往不是同时“输出”，而是回收能量\功率，这也是再生的含义）。更有的设计中，允许一侧正向另一侧反向转动，实现原位转向，或是中心转向。第一种成功的设计是英国1924年的双差速设计，之后被美国、德国模仿（？？那个时候维克斯中型坦克Mk2等等还是威尔逊转向，尚且没有查到24年具体是什么设计）

Most modern Western designs use a variation of the double differential, while Soviet designs preferred to use two separate transmissions in a single housing. Systems using electric motors with variable speed controls have been tried on a number of occasions, but have not entered widespread service.

更加现代的西方设计使用双差速转向的变种发展，而苏联设计中偏爱放在一起的双侧传动。（in a single housing似乎一般指做成一个总成，这并不成立）。利用电机的可变速度控制有很多实验，但是并没有广泛使用。

One solution to the steering problem is to use two separate drivetrains, each driving one track. This maintains power to both tracks while steering, produces a wide range of turning circles, and even allows one track to be reversed while the other moves forward, allowing the tank to turn in place. This may be combined with brakes to further control the steering radius.[1]

早期的转向问题的解决办法是使用两侧独立的驱动系统。两侧履带在行进转向中都有独立的动力系统驱动，能够实现几乎任意的转向，包括能够一侧前进一侧倒转的原位转向。这需要使用制动来控制半径。（由需要制动可以看出，本身可控性也并不理想）

The obvious disadvantage to this design is the cost and complexity of two drive trains, and the increased maintenance load that implies. Another is that if one engine fails, the other cannot be used to drive both tracks. Both of these problems were greatly reduced in the case of steam power, where the majority of the engine in terms of size and weight is the boiler, and the cylinders that extract that power are much smaller in comparison. It can also provide variable output by controlling the amount of steam sent to each cylinder. It is much more complex when used with internal combustion engines.[1]

显然使用两套动力系统，其造价、复杂性、维护性都不理想。而一旦一套系统出问题，整车将失去行驶能力。不过在早期的蒸汽动力时代这个问题并不关键，左右两侧动力来源蒸汽机，能够使用共用的锅炉，而两套蒸汽机带来的重量、控制、复杂性的增加则是可以容忍的，蒸汽机的动力通过控制进入气缸的蒸汽来实现，而使用内燃机则麻烦多了。（蒸汽机的输出特性曲线要比内燃机宽泛，而内燃机不能简单通过油门风门控制）

A less obvious problem is that it is very difficult to keep such a vehicle moving in a straight line. Although a governor can be used to ensure the two engine speeds are similar, loads on the tracks will not be the same as it moves over different terrain, causing the more heavily loaded track to slow and the tank to turn in that direction. This will cause the tank to wander when moving over uneven ground. This is not an issue at very low speeds, and the system is sometimes used on bulldozers and other tracked construction vehicles. For tanks, considerable driver skill and constant adjustment are needed, even at the relatively low speeds seen on early designs.[1]

另一个不那么明显的问题是，这样的车辆很难保持直行。尽管使用阀门控制两侧的动力、速度尽量相近，但是复杂地形中则很难做到，一侧履带遇到更大的阻力会自动降速，导致向这边转向。于是在复杂地形上车辆的行驶将会是左右乱晃的。在很低速度下，这个问题也能够容忍，于是在推土机等工程车辆上也有这样的应用。对于坦克，则需要更高的驾驶技巧、更加频繁的调整。

Examples of true twin-drive systems are not common, but have existed through much of tank history. Examples include the World War I-era British Whippet medium tank,[2] and the M5 Stuart.

这一类很少见，例如一战时代的英国小猎犬、M5斯图尔特（M5不是！！！尽管有两个发动机、两套液力耦合的行星变速器，却是并联起来交给一个2档减速器的，转向还是通过2档减速器之后的单一克利夫兰转向机实现的！！！德国的A7V、法国的圣沙蒙属于这一类，前者是内燃机驱动，后者是电力驱动）

Soviet tanks, like this T-72, use advanced variants of the dual transmission system to this day.

苏联的例如T72使用更加高级的双传动系统。（T72的先进程度十分有限，实际上麻烦更多）

A simple step up from the dual-drive concept is to use a single engine and split the power output into two transmissions. Steering is accomplished by changing the gear on one track and not the other. This reduces the complexity of the dual-drive system when combined with a modern engine. It also introduces a new behaviour; additional load on one track causes the other to slow as well. This is actually an improvement over the dual drive solution, as it causes the entire tank to slow, not turn towards the loaded track.[3]

在双侧独立驱动基础上，（恐怕也不是所谓基础，尽管出现也很早）就是共用发动机，将动力分给两个传动系统。转向则是通过两侧档位不同实现的。这样和使用内燃机的双侧独立驱动相比，复杂性降低。这样带来了新的特性，当一侧负载增加（阻力加大？）整车都会降速，而不是向一侧转向。这是相对于双独立动力的一个优越的改进。

The downside to this approach is that high-power transmissions are failure-prone devices, especially in the World War II era. They are also complex and time-consuming devices to build and repair. Although it eliminates a second engine, compared to the dual-drive concept, it is still relatively complex compared to the solutions that follow.[3]

不足在于，高功率的传动系统是易损的，尤其在WW2时代。这样的系统也较为复杂、难以维修。尽管省去了第二台发动机，依旧是较为复杂的。（？？？从行星轮控制的角度，并不比别的更加复杂；从维修的角度，也不见的比离合制动更加麻烦很多）

Dual-drive systems were widely used since the earliest days of tracked vehicles, including the Holt 75 tractor that saw widespread use in World War I.[4] The Japanese adopted the concept in 1925, and all their subsequent tanks through World War II used this. The British also continued to use it on light tanks like the Covenanter and Crusader of the early war period. The Czech LTH also adopted the system, seeing service with the Germans as the Panzer 38(t).[3]

作为一种出现很早的系统，得到了广泛的使用，包括WW1时代的霍尔特75（不是！！！霍尔特75本身是典形的两侧有离合器的半履带车辆，经过简单改装之后成为去掉转向前轮的离合制动转向！！！）日本在1925年起采用这类系统，一直用到了WW2时代。英国的盟约者、十字军也使用了。杰克的38t也是。（显然这里指的是二级行星转向，变速并不包括在内，因此双传动并不准确）

The Soviets introduced this system for their KV-13 experimental tank, and this led to its use in the IS tank family. Later versions introduced more gears to produce multiple turning radii, including reversing one track. The T-64 introduced a new model with seven speeds, and this basic system has been used on the T-72, T-90 and Chinese Type 98.[3][5]

苏联在KV13上最先应用，之后用于IS系列上（42年底kv13得到负面评价，但是43年有了新炮塔原型车，43年中生产了kv1s）。后来将每侧转向机增加更多的档位代替变速箱，实现更多的半径包括一侧倒车（这显然就是在说T72为代表的双侧变速兼转向设计。而实际情况是工作中真正有用的半径还是一个，只能下将一个档位，且有的状态下半径并不合适，需要活动摩擦机件。一侧倒档也没有实际实现，仅仅是存在可能）T64上使用了7速，这一类系统用于T72、T90、中国98式（呵呵98式）

The T-34 was one of the most successful tanks designed specifically to use the clutch steering system.

T34是最有名的使用离合制动转向的。

The simplest single-engine steering system in mechanical terms, and almost universally used on early tank designs, was the combination of a brake and a clutch connected to steering controls. The controls were normally a pair of vertical handles, one for each track. Pulling on a handle disengaged the clutch, releasing that track and causing it to slow down. Further motion of the handle increasingly applied the brake to that track, allowing the turning circle to be adjusted.[3]

机械上最简单的转向系统，广泛用于早期坦克，将每侧履带安装离合器、制动器实现转向控制。操作通常通过拉杆实现，断开一侧离合器，利用自然阻力令这一侧主动轮实现单侧减速。进一步继续拉杆进行制动，按需制动得到想要的转弯半径。

The main disadvantage of this design is that when steering is applied the engine power is removed from the track. This makes the tank slow down, even if the brake is not applied. If the tank is climbing, or in soft terrain, forward motion may stop entirely. Another disadvantage is that the brakes constantly dissipate vast amounts of heat when steering, which is very power-inefficient. The brakes suitable to steer a large vehicle are also impracticably large.[3]

最大的不足是，一侧断开动力。这样车辆会减速，即使不施加制动。上坡中，或是软质路面上，甚至可能断开的一侧完全不再前进（也就是滚动阻力本身就很大，那么半联离合不就可以了么？好吧半联本身是比较麻烦的做法，和制动一样由于滑动摩擦产生热量累计，还更加不容易散热）。另一个问题是转向中的持续制动将会产生大量的热量，大大降低了效率。对于大型车辆，需要的制动器也十分大。（从再生的角度，这种转向完全没再生能力）

Clutch braking was introduced by the French in 1916 during World War I. Most light tanks used it through the 1920s and 30, as well as some larger tanks like the British experimental Vickers Independent and Soviet T-35. The last major designs to use it were the Soviet T-34 and German Panzer III and Panzer IV.[3]

最先出现在1916年的法国（应该指施耐德，但是之前霍尔特上已经实验性地使用了）在轻型坦克上时候用直到30年代，另外还有一些大型的也使用了，例如英国独立、苏联T35。最后的使用是苏联T34、德国3号4号（3号4号本质上是离合制动式，这是正确的，尽管形式上是行星排，和一战的MK5一样，这也是mono说过的“一战水平”说法的来源。最后的军用可能还是60、70年代的BMD1/2，尽管是轻型车辆）

The Universal Carrier used braked differential system as well as track warping.

差速器制动转向。英国的通用载具用了（不用猜就知道，一堆英国小坦克都用）

Differential braking (or braked differential) systems remove the clutches on the track and add a differential on the transmission output. The differential allows the tracks to turn at different speeds while remaining powered. Steering is then accomplished by slowing one track with a brake. The advantage to this design is that power is maintained to both tracks even while steering is taking place. Another advantage is outright simplicity; the steering system connects directly to the brake and nothing else, producing a very simple mechanical arrangement.[3]

这也是一种十分简单的系统，仅仅需要一个差速桥、两侧两个制动器。和离合制动转向相比，仅仅有两个动作操作元件，而离合制动系统还有多出来的两个离合器。

The main disadvantage, like the clutch braking system, is that steering dissipates heat through the brakes. Unlike the clutched system, however, in this case all turning requires braking. This can be used on lighter tanks, but the amount of kinetic energy in larger tanks makes the required brakes impractically large. Another disadvantage is that the differential will allow the tracks to turn at different speeds no matter what the cause may be. This may be the application of braking, but also occurs as the tank travels over terrain; if one side of the tank enters softer terrain and slows down, the tank will naturally turn towards that side. Forward momentum tends to offset this effect, so it is mainly a problem at low speeds.[3]

主要的问题不足，就像离合制动系统，转向中制动器消耗太多的功率（实际上远多于离合制动）。不同于离合制动转向的是，这时所有的转向都需要制动（应该指没有利用一侧自然阻力的转向）。这种系统能够用在轻型车辆上，但是由于需要制动消耗的能量、动能太高，在更重的车辆上制动器就需要十分巨大。另一点是这种差速器制动的差速、转向经常不可控，可能是由于制动力产生的人为速度差，也可能是由于地面地形、阻力，可能在没有制动操作情况下由于地面阻力、坡度而自动转向。若是速度足够高，车身自身的动量/惯性可能一定程度上弥补这种自转向，但是低速下这就是很大的问题。（为什么不考虑差速锁？没有听说过差速锁。轻型车辆通过飙到高速能够避免自转向问题，但是从低速加速到高速的过程本身就是难以达到的、修正代价较大的。）

Differential braking actually predates clutch braking on tracked vehicles, having been initially introduced by Richard Hornsby & Sons in 1905 on the world's first tracked vehicle. Clutch braking became popular only because of its mechanical simplicity. Differential braking could be found on many smaller tanks, especially in the pre-World War II era. British tanks began using them during World War I, and continued into World War II. One common example was the Bren Carrier.[3]

差速器制动转向要早于离合制动转向，在1905年就取得专利。离合制动更加受欢迎仅仅是因为其简单（不是！！在转向效率也就是制动器消耗的能量上、在提供的牵引力上离合制动都更加优越！！！）差速器制动转向在很多小坦克上使用，尤其是二战前。应该在一战开始使用知道二战（一战时代的哪个是差速器制动的？？？MK1到4的蜗杆减速器内部到底有没有差速器？若是有，两侧的变速机构不就废了？？难道存在差速锁？？？）典型的例子是布伦通用载具，（以及一系列维克斯轻型坦克，再加上领主、放大版的霍普金斯……）。

The M113 is the most widely used military example of the controlled differential system.[citation needed]M113是产量最大的这一类（8w辆）

Differential braking systems are essentially an epicyclic transmission with a single fixed gear ratio transmitted through idler pinions. The controlled differential adds an extension to the rack holding the idlers, and puts a conventional brake on that extension. With the brake applied, the idlers are locked and the system works like a conventional epicyclic. When the brake is released, the idlers spin, reducing the speed of rotation on that side. This causes the output on that side to slow down by a fixed amount.[3]

差速器制动转向系统，本质上是一种行星传动，其中的固定齿比的齿轮通过“惰轮”小齿轮左右咬合实现。（这里显然排除了锥形齿轮的差速桥）。而克利夫兰转向机则是在差速桥基础上扩展，中央旋转的小齿轮架上延伸了一重同轴小齿轮，（形成了一种双联外啮合行星排）并对扩展出来的部分（多出来的太阳轮）进行制动控制。制动之后，这个系统就像是行星排一样。释放制动之后，“惰轮”恢复继续旋转（这里的惰轮应该指扩展出来的一重太阳轮）。制动抱死之后，这一侧半轴也会保持一定的转速。

The advantage to this design is that the brake is not being applied to slow the vehicle, it is simply clutching the second set of gears in or out. This means it does not dissipate energy, except in the brief period it is being applied or released. Smoother steering can be accomplished by partial application of the brake, but then it begins to dissipate energy like the braked differential. The main disadvantage is that there is only one turning radius. Like the standard differential solution, these systems are also subject to self-turning when travelling over terrain.[3]

最大的优点在于，这个制动器不会造成车速的下降，仅仅是令第二组齿轮参加传动，这意味着不会损失功率。更加平滑的转向可以通过部分制动实现，这个时候就会消耗功率，就像差速器制动一样。最大的不足是仅有一个转向半径。就像是标准的差速制动方案一样，这个系统也存在越野中自转向的现象（制动器位置上发生滑动摩擦造成的损失是不可忽略的、和二级行星相比要更大的。制动器吃掉功率之后，剩下的部分功率用于驱动车辆，机动性显然不会保持。加上外侧履带牵引力作用更加重要，在制动器吃掉相同功率条件下，外部速度更高而扭矩更低的克利夫兰转向要比二级行星更加难以保持机动性）

The system was invented by Cleveland Tractor Company in 1921, and is sometimes known by the trademarked name Cletrac Differential. It was used by most French tanks in the inter-war era, as well as on the German Grosstraktor. It was most common on US designs, used on all light and mediums from 1932 until the end of World War II. Later uses included the French AMX 13, Japanese Type 61, and the widely produced US M113 APC.[3]

发明专是21年克利夫兰拖拉机公司得到的（有说法是出现于16年或是18年，且是从贝斯特公司购买的，存疑。不过贝斯特的产品是使用差速器的半履带拖拉机，也应该需要降低导向轮磨损、减小转向半径的）。间战期很多法国坦克使用过，德国大型拖拉机（莱茵金属？）也用过。作为发明地，美国从30年代的轻型坦克开始使用，著名的就是M4。最后是使用包括了法国的AMX13、日本61、美国M113.。