1、广东技术师范学院天河学院本科毕业设计外文翻译译文学生姓名 院（系） 广东技术师范学院天河学院 专业班级 机械设计制造及其自动化 指导教师 完成日期 外文出处：http:/ Piston PumpsIn axial piston pumps of the in-line type, where the cylinders and the drive shaft are parallel ,the reciprocating motion is created by a cam plate, also known as a wobble plate ,tilting plate ,or swash
2、 plate .This plate lies in a plane plate that cuts across the center line of the drive shaft and cylinder barrel and does not rotate .In a fixed-displacement pump ,the cam plate will be rigidly mounted in a position so that it intersects the center line of the cylinder barrel at an angle approximate
3、ly 25 degrees from perpendicular .Variable-delivery axial piston pumps are designed ,so that the angle that the cam plate makes with a perpendicular to the center line of the cylinder barrel may be varied from zero to 20 or 25 degrees to one or both sides. One end of each piston rod is held in conta
4、ct with the cam plate as the cylinder block and piston assembly rotates with the drive shaft This causes the pistons to reciprocate within the cylinders .The length of the piston stroke is proportional to the angle that the cam plate is set from perpendicular to the center line of the cylinder barre
5、l .A variation of axial piston pump is the bent-axis type shown in figure 4-14.This type does not have a tilting cam plate as the in-line pump does .Instead ,the cylinder block axial is varied from the drive shaft axis .The ends of the connecting rods are retained in sockets on a disc that turns wit
6、h the drive shaft .The cylinder block is turned with the drive shaft by a universal joint assembly at the intersection of the drive shaft and the cylinder block shaft ,In order to vary the pump displacement ,the cylinder block shaft and valve plate are mounted in a yoke and the entire assembly is sw
7、ung in an are around a pair of mounting pintles attacked to the pump housing .Figure 4-14 Bent axis axial piston pumpThe pumping action of the axial piston pump is made possible by a universal joint or link .Figure 4-15 is a series of drawings that illustrates how the universal joint is used in the
8、operation of this pump .First ,a rocker arm is installed on a horizontal shaft .(See fig 4-15 view A )The arm is joined to the shaft by a pin so that it can be swung back and forth ,as indicated in view B。Next, a ring is placed around the shaft and secured to the rocker arm so the ring can turn from
9、 left to right as shown in view C, This provides two rotary motions in different planes at the same time and in varying proportions as may be desired .The rocker arm can swing back and forth in one arc ,and the ring can simultaneously move from left to right in another arc ,in a plane at right angle
10、s to the plane in which the rocker arc turns .Next ,a tilting plate is added to the assembly .The tilting plate is placed at a slant to the axial of the shaft, as depicted in figure 4-15,view D. The rocker arm is then slanted at the same angle as the tilting plate ,so that it lies parallel to the ti
11、lting plate .The ring is also parallel to ,and in contact with ,the tilting plate .The position of the ring in relation to the rocker arm is unchanged from that shown in figure 4-15,view C.Figure 4-15 view E shows the assembly after the shaft ,still in a horizontal position ,has been rotated a quart
12、er turn .The rocker arm is still in the same position as the tilting plate and oscar now perpendicular to the axial of the shaft The ring has turned on the rocker pinstripe ,so that it has changed its position in relation to the rocker arm ,but it remains parallel to ,and in contact with the tilting
13、 plate .View F of figure 4-15 shows the assembly after the shaft has been rotated another quarter turn. The parts are now in the same position as shown in view D, but with the ends of the rocker arm reversed ,The ring still bears against the tilting plate .As the shaft continues to rotate ,the rocke
14、r arm and the ring turn about their pivots ,with each changing its relation to the other and with the ring always bearing on the plate .Figure 4-15, view G wheel added to the assembly .The wheel is placed upright and fixed to the shaft ,so that rotates with the shaft .In addition ,two rods A and B,
15、are loosely connected to the tilting ring and extend through two holes sanding opposite each other in the fixed wheel. As the shaft is rotated ,the fixed wheel turns perpendicular to the shaft at all times. The tilting ring rotates with the shaft and always remains tilted ,since it remains in contac
16、t with the tilting plate .Referring to view G , the distance along rod A ,from the tilting ring to the fixed wheel ,is greater than the distance along rod B .As the assembly is rotated ,however ,the distance along rod A decreases as its point of attachment to the tilting ring moves closer to the fix
17、ed wheel ,while the distance along rod B increases. These changes continue until after a half revolution ,at which time the initial positions of the rods have been reversed .After another half revolution ,the two rods will again be in their original positions.As the assembly rotates ,the rods move i
18、n and out through the holes in the fixed wheel .This is the way the axial piston pump works. To get a pumping action , place pistons at the ends of the rods ,beyond the fixed wheel and insert them into cylinder .The rods must be connected to the pistons and to the wheel by ball and socket joints .As
19、 the assembly rotates ,each piston moves back and forth in its cylinder .Suction and discharge lines can be arranged so that liquid enters the cylinder while the spaces between the piston heads and the bases of the cylinder are increasing and leaves the cylinder during the other half each revolution
20、 when the pistons are moving in the opposite direction. The main parts of the pump are the drive shaft , pistons ,cylinder block , and valve and swash plates , There are two parts in the valve plate . These Portsmouth connect directly to openings in the face of the cylinder block . Fluid is drawn in
21、to one port and forced out the other port by the reciprocating action of the pistons .Figure 4-15 Relationship of the universal joint in operation of the axial piston IN-LINE-VARIABLE-DISPLACEMENT AXIAL-POSTON-PUMP-When the drive shaft is rotated , it rotates the pistons and the cylinder block with
22、it . The swash plate placed at an angle causes the pistons to move back and forth in the cylinder block while the shaft , piston , cylinder block and swash plate rotate together (The shaft piston , cylinder block , and swash plate together is sometimes referred to as the rotating group or assembly )
23、 . As the pistons reciprocate in the cylinder block, fluid enters one port and is forced out the other.The tilt or angle of the swash plate determines the distance the pistons move back and forth in their cylinder, thereby, controlling the pump output .When the swash plate is at a right angle to the
24、 shaft, and the pump is rotating, the pistons do not reciprocate, therefore, no pumping action takes place. When the swash plate is tilted away from a right angle, the pistons reciprocate and fluid is pumped .Since the displacement of this type of pump is varied by changing the angle of the tilting
25、box, some means must be used to control the changes of this movement-manual, electric, pneumatic, or hydraulic .外文中文翻译：轴向柱塞泵轴向柱塞泵是一种典型的同轴的泵，它的汽缸和传动轴式平行的，它的往复运动被一个平板型凸轮带动，也叫摆动盘，倾斜盘，或旋转斜盘。这个盘位于一个平面穿过主动轴和气缸筒的同一轴线，所以不能旋转。在定量泵中，凸轮盘必须要求严格的安装在合适的位置上，结果它与气缸筒的中心线以垂直方向倾斜 25 度的角度交叉。变量传输的轴向柱塞泵的设计是有意图的，所以凸轮盘与气缸筒
26、中心线的正交处变化范围在 0到 20或 25到两侧。每个活塞杆的末端被用来与凸轮盘相接触，因为汽缸体和活塞的转配同传动轴，一起旋转。这引起了活塞在气缸内的互换。活塞的长度是与角度成比例的，这个角度是凸轮盘的位置与气缸筒中心线垂直方向的角度。一个变化的轴向柱塞泵是一个倾向轴的类型，如图 4-14。这种类型的泵没有倾斜的凸轮盘，类似于同轴泵。取而代之，汽缸体轴不同于传动抽。连杆的末端保留在圆盘上面的孔内这样与传动轴一起旋转。汽缸体随传动端一起旋转在传动轴与汽缸体活塞杆的通用交叉点的带动下。为了去改变泵的排量，汽缸体和阀盘被连接好并且整个装置是摆动的，在一对装备枢轴的周围放在泵房上。轴向柱塞泵的动作
27、是由万向接头或链接促成的。图 4-15 是一系列的图那些是举例说明在泵的操作过程中怎样使用万向接头。首先摇杆臂被安装在水平杆上（看图 4-15 图 A） ，臂被一个销钉连接在杆状物上所以能来回的摇动，就像图 B 所示。接下来，一个环放在杆状物的周围来保护摇杆臂，所以换可以左右来回转，如图 C 所示。这样可以提供你可能需要的在同一时间不同位面变化比例的两个旋转运动。摇杆臂能在一弧形内来回摇摆，并且环能同时在另一弧形内前后的摇摆，在平面内以一个恰当的角度，这个平面式摇杆臂旋转。下一个在总装中增加一个倾斜的平面。这个倾斜的平面放在杆状物轴心倾斜的位置上，像图 4-15 中 D 描述的那样。摇杆臂在这
28、时倾斜的位置与倾斜盘的是同一位置，所以基本上是与倾斜盘上平行的。这个环也是平行的，它与倾斜盘相接触。环的位置与摇杆臂是有关联的，而且是无法改变的，从图 4-15C 可知。从 4-15E 中可知，杆体装完以后，仍然在一水平位置，使其直角旋转。摇杆臂仍然和倾斜盘在同一位置上，而且正交与杆状物的轴线。环可以在摇杆销上旋转。与摇杆臂相比它能改变自己的位置，但是它必须保持平行，并且要与倾斜盘相接触。图 4-15F 所示杆状物在另一个直角拐弯处被旋转。这些零部件处于同一位置如图 D 所示，但是同摇杆臂的末端一起翻转。环仍然承担着反向的倾斜盘。当杆继续旋转时，伴随各自相互关联的变化和环总是对盘施加压力使摇杆
29、臂环改变它们的支点。图 4-15G 所示有一个附加轮子的装置，这个轮子是竖直放置并固定在轴上，所以它和轴一起旋转。另外，两杆 A 和 B，松散的连接在倾斜的环上并伸出穿过两个直的洞，相互对立的安装在轮子上。因为杆是旋转的，固定的轮一直垂直的转向杆。倾斜的环一直杆一起旋转而且一直保持倾斜的状态，之后始终保持着与倾斜盘的接触，提到的图 G，沿着杆 A 从倾斜环到固定轮的距离比沿着杆 B 的距离要重要的多。随着使总装的旋转，然而，沿着杆 A 的距离随着把它的尖端放在倾斜环上，并向固定轮附近移动而减少，沿着杆 B 时会增加。这些变换会继续直到旋转一半以后，在此刻杆的初始位置被翻转。当另一半旋转后，两个
30、干将再一次回到其初始位置。当总装旋转时，杆将在固定轮子的孔内来回的移动。这就是轴向柱塞泵的工作方式。为了使泵持续工作，活塞安放在杆的末端，超出发的轮的一侧插入气缸内。杆必须与活塞和轮子被球窝接头相连。由于旋转装配，每个活塞在它的缸体内来回运动，吸入和排出的路线已经计划好，所以当活塞头和缸体之间的空间逐渐增大时液体进入气缸内，当活塞向反向移动时汽缸的另一部分在旋转。泵的主要部分包括传动轴，活塞，汽缸体，阀和冲洗金属板等。它们是在对端的阀体上，这些端口直接对着汽缸体。液体被活塞的往复运动使其从一端口吸入从一端口排出。同轴的变量的轴向柱塞泵- 当传动轴旋转时，它的活塞和汽缸体也一起旋转。旋转斜盘倾斜
31、放置。当活塞杆，活塞，缸体，和旋转斜盘一起旋转时引起活塞在液缸体中的来回移动。由于活塞在汽缸体内的互换，液体从一端吸入从另一端排出。知道旋转斜盘的倾斜或角度能确定活塞在汽缸内往复移动的距离，因此，可控制泵的排量。当旋转斜盘在杆的垂直位置时，泵的活塞不能进行互换旋转，因此不可能有抽吸动作的发生。当旋转斜盘倾斜到远离直角的位置时，活塞开始互换液体，可以来回的抽取。自从这类型的各种各样的泵被角度式的摆动箱体所替换后，必须要采取一些措施去控制这种角度式的替换。各种各样的方法被采用去控制这种动作-手动的、电动的、气动的或水力的。翻译工具有：牛津高阶英汉双解词典（第六版）牛津大学出版社机械工程专业英语（第十版）哈尔滨工业大学出版社
