差速器和主减速器

差速器和主减速器(中文5000字,英文5000字)
术语差速器、变速箱和主减速器的使用有时并不精确，这些机器经常以各种各样的组合被集成在同一子系统中，本章就介绍了有助于阐明此问题的定义。
差速器是允许输入轴转矩分为预定两部分的机器，通过两个输出轴，转矩比独立于同轴速度比。
这种机构既可以把主减速器转矩划分为等份，作用在同一车轴的牵引轮上，或者把齿轮箱转矩分成两个预定部分，作用于相同或不同的车轴。第二种应用有时被称为变速箱差速器或中央差速器。
主减速器是一个齿轮系，可进一步降低齿轮箱输出轴的速度，以使其适应牵引轮，通常与差速器一起用。具有减速作用、安装在输电线路差速器上且最终集成在轮毂的机器有时都可以叫这个名字。
变速箱可通过齿轮箱的单输出轴提供两个或多个驱动线的运动，用于多牵引轴车辆。如果多轴牵引是永久性的，那么就需要一个差速器使车轴有不同的平均旋转速度，这种情况下，差速器通常集成在变速箱。

DIFFERENTIALS ANDFINALDRIVES
The terms differential, transfer box and final drive are sometimes used imprecisely;in addition, these mechanisms are often integrated in the same subsystemin a wide variety of combinations. In this chapter we introduce definitions thatshould help to clarify this issue.
The differential is a mechanism that allows the torque from an input shaftto be divided into two predetermined parts, flowing through two output shafts;torque ratios are independent of the speed ratios of the same shafts.
This mechanism can be used either to divide the torque coming out of thefinal drive into equal parts acting on the traction wheels of the same axle, or todivide the torque coming out of the gearbox into two predetermined parts actingon different axles of the same vehicle. This second application is sometimes calledthe transfer box differential or central differential.
The final drive is a gear train that further reduces the speed of the gearboxoutput shaft to adapt it to the traction wheels; this gear train is usually integratedwith a differential mechanism. Under this name are sometimes included those speed reducers that are put on the transmission line after the differential final drive and integrated in the wheel hub.
The transfer box is a mechanism that provides for the movement of two or more drivelines through the single output shaft of the gearbox; it is used on vehicles with multiple traction axles. When multiple axle traction is permanent a differential is also needed to allow different mean rotation speeds on the axles; in such cases the differential train is usually integrated in the transfer box.