齿轮机械机构类外文翻译、中英文翻译

外文原文

Gears

Gears are vital factors in machinery ,which are uses to transmit power

or motion from one shaft to another .They may be used only to transmit

motion from one part of a machine to another,or they may be used to change

the speed or the torque of one shaft with with relation to

of the first mechanism invented using gears wad the fact,a clock

is little more than a train of erable study and research have

been made on gears in recent years because of their wide use under exacting

have to transmit heavier loads and run at high speeds than

ever engineers and the machinists all consider gearing the

prime element in nearly all classes of machinery.

Super Gears

Spur gears will be considered first for several the first

place ,they are simplest and the least expensive of gears and they may

be used to transmit power between parallel shafts,also,spur gears

definitions are usually applicable to other types .It is important go

understand the following definitions,since they are important factors in

the design of any equipment utilizing gears.

Diametric Pitch

The number of teeth per inch of pitch cirle diameter .The diameter pitch

is usually an integer .A small number for the pitch implies a large tooth

g spur gears must have the same diameter pitch .The speed ratio

is based on the fact that meshing gears may have different-sized pitch

circles and hence different number of teeth.

Circular Pitch

The distance from a point on one tooth to the corresponding point on

an adjacent tooth ,measrued along the pitch is a liner

dimension and thus bas liner units.

Pitch Circle

The circle on which the ratio of the gear set is based,when two gears

are meshing ,the two pitch circles must be exactly tangent if the gears

are to function tangency point is known as the pitch point.

Pressure Angle

The angle between the line of action and a line perpendicular to the

centerlines of the two gears in mesing .Pressure Angles for spur gears

are usually 14.5 or 20 degrees,although other values can be g

gears must have the same pressure the case of a rack,the teeth

have the straight sides inclined at an angle corresponding to the pressure

angle.

Base Circle

A circle tangent to the line of action (or pressure line ) .The base

circle is the imaginary circle about which an involutes cure is

developed .Most spur gears follow an involutes cure from the base circle

to the top of the tootch,this cure can be visualized by observing a point

on a taut cord an it is unwound from a cylinder .In a gear ,the cylinder

is the best circle.

Addendum

The radial distance form the pitch circle to the top of the tooth .

Dedendum

The radial distance from file pitch circle to the root of the tooth.

Clearance

The difference between the addendum and the addendum.

Face Width

The width of the tooth measured axially.

Face

The surface between the pitch circle and the top of the tooth.

Flank

The surface between the pitch circle and the bottom of the tooth.

Helical Gears

These gears have their tooth element at an angle or helix to the axis

of the are more difficult and expensive to make than spur

gears,but are quieter and stronger. They may be used to transmit power

between parallel shafts at an angle to each in the same or different

planes.

Herringbone Gears

A herringbone gear is equivalent to a right-hand and a left-hand

helical gear placed side by e of the angle of the tooth,helical

gears create considerable side thrust on the shaft. A herringbone gear

corrects this thrust by neutralizing it ,allowing the use of a small thrust

bearing instead of a large one and perhaps eliminating one

a central groove is made round the gear for ease in

machining.

Bevel Gears

Bevel gears are used to connect shafts, which are not parallel to each

y the shafts are 90 each other, but they may be more

or less than 90 two meshing gears may have the same number of teeth

for the purpose of changing direction of motion only,or they may have a

different number of teeth for the purpose of changing both speed and

direction .The faces of the teeth lie on the surface of the frustum of

a cone,therefore the teeth elements are not parallel to each other it can

be seen that this lack of parallelism creates a machining problem so that

two passes with a tool must be tooth elements may be straight

or spiral ,so that we have plain anti spiral evel gears.

Worm and Worm Gears

A worm-and-worm-gear combination is used chiefly where it is desired

to obtain a high gear reduction in a limited space,normally the worm

drivers the worm gear and is not reversible ,that is to say,the worm gear

can not drive the worms can be rotated in either

direction,clockwise or counterclockwise.

Racks

A rack is a gear with an infinite radius,or a gear with its perimeter

stretched out into a straight is used to change reciprocating

motion to rotary motion or vice versa.A lathe rack and pinion is a good

example of this mechanism.

Various materials are used in manufacturing gears .Usually,the

materials selected depends on the method used for making the gear and the

application to which it will be can be cast,cut,or

l materials include cast iron,cast steel,plain carbon

steel,alloy steel aluminum,phosphor bronze,laminated phonetics,and

nylon.

中文翻译

齿轮

齿轮是机器中的动力元件,用来传递轴与轴之间的运动及动力。它们可能仅被用来传递运动,即机器的一个部分到另一个部分,或者被用来改变轴与轴之间相对速度和转矩,第一个被发现用齿轮的机器是钟表,事实上,钟表的齿轮与火车上的齿轮相比是非常小的。由于齿轮在实际环境中的广泛应用,人们在齿轮的应用方面进行了许多的研究和调查。现在,齿轮传动比起以前来不得不传递很重的载荷,和在高速度下运转。目前工程师和机械师都在考虑存在于机械中的这种因素。

直齿圆柱齿轮

直齿圆柱齿轮被作为传动中的首选有许多原因。它们是最简单也是最廉价的，并且它们可以被用作传动平行轴之间的力，还有它的概念同于其它类型的齿轮，以下的几个定义是非常重要的，因为，它们在设计任何与齿轮有关的方面都是非常重要的。

径节

节圆直径单位距离上的齿数，径节通常是一个整数。小小的一段齿距包括了许多的齿形。直齿圆柱齿轮啮合的条件是必须有相同的径节，齿轮的传动比决定于啮合齿轮的不同的节圆和不同数目的齿数。

齿距

沿着节圆从齿上的一点到临近齿上对应相同的另一点的距离，这是一个线尺寸和线性单位。

节圆

作为齿轮比率设定基础的圆。若要是互相啮合的齿轮正常运行，则两节圆必须精确相切。

压力角

运动方向与垂直于两啮合齿轮中心线的直线所形成的夹角。对于直齿圆柱齿轮压力角为14.5度或20度，因此可以有许多的用途，相啮合的齿轮必须有相同的压力角。对于齿条，齿相对于直边有与压力角相同的倾斜角度。

基圆

与运动方向相切（或与压力角方向相切）的圆。基圆是产生渐开线所假想的圆。许多直齿圆柱齿轮都是渐开线从基圆到齿顶，当绷紧绳索从一个圆柱体展开时，仔细观察绳索上某点的运动，即可想象出此段渐开线的形状。在齿轮中，基圆是最主要的圆。

齿顶高

从节圆到齿顶的径向距离。

齿根高

从节圆到齿底的径向距离。

间隙

齿顶高与齿根高之间的不同。

面宽

齿在轴向的宽度。

面

节圆和齿顶之间的表面。

齿腹

节圆和齿底之间的表面。

斜齿轮

这些齿轮的齿相对于齿轮轴线由一个角度或螺旋角度，它们比直齿圆柱齿轮的制造更难，造价更昂贵，但是它们传动无噪音并且可靠。它们可以用来在相同或不同平面中构成一定角度的相两轴之间的力的传递。

人字形齿轮

人字形齿轮是在齿轮两边有相同数量在左旋和右旋形的齿轮。由于齿轮有角度，齿轮制造时需要考虑轴受到的轴向力，人字形齿轮是用平衡的方法来抵消轴向推力的，固而允许选用轻系列轴承取代重系列轴承，甚至可以完全取消轴承，通常在切削加工中在齿轮的周围有一个中心槽来抵消。

锥齿轮

锥齿轮用作互相不平行的轴之间的连接。

通常轴之间的夹角是90度，但它们比90多或少，相啮合的两齿轮仅改变运动方向，或者为改变速度具有不同的齿数，齿的表面沿着圆锥的表面，圆头齿之间不相互平行，它就使得在机械加工中产生类似的问题及必须要一套夹具。齿轮的线可能是直的或螺旋的，因此有平直的锥齿和螺旋的锥齿。

蜗杆和蜗轮

蜗杆蜗轮机构主要用作有限空间需较小齿轮的体积的情况。通常蜗杆为主动件并且不能颠倒，也就是说，蜗轮不能作为主动件。许多蜗杆能左右移动，转动为顺时针或逆时针。

齿条

齿条是有无穷半径的齿轮或是边缘随着直线扩展的齿轮，它被用来往复运动改变为螺旋运动或反过来，车床齿条和小齿轮是这种机器的最好例子。

各种材料被用于制造齿轮。通常被选用的材料取决于齿轮的制造与齿轮将来的实现用途，齿轮能被铸，轧或挤压出来。材料类型包括：铸铁碳素钢，合金钢，铝，青铜，尼龙。