外文翻译- 液压系统概述.docx

1、外文资料与中文翻译外文资料：Hydraulic SystemHydraulic presser drive and air pressure drive hydraulic fluid as the transmission is made according to the 17th century, Pascals principle of hydrostatic pressure to drive the development of an emerging technology, the United Kingdom in 1795 Braman Joseph (Joseph Brama

2、n ,1749-1814), in London water as a medium to form hydraulic press used in industry, the birth of the worlds first hydraulic press. Media work in 1905 will be replaced by oil-water and further improved.AftertheWorld War I (1914-1918),becauseof theextensive application of hydraulic transmission, espe

3、c- ially after 1920, more rapid development. Hydraulic components in the late 19th century about the early 20th century, 20 years, only started to enter the formalphase of industrial production. 1925 Vickers (F. Vikers) the invention of the pressure balanced vane pump, hydraulic components for the m

4、odern industrial or hydraulic transmission of the gradual establishment of the foundation. The early 20th century G Constantimscofluct - uations of the energy carried out by passing theoretical and practical research; in 1910 on the hydraulic trans- mission (hydraulic coupling, hydraulic torque conv

5、erter, etc.) contributions, so that these two areas of develo-pment.The Second World War (1941-1945) period, in the United States 30%of machine tool applications in the hydraulic transmission. It should be noted that the development of hydraulic transmission in Japan than Europeand the United States

6、 and other countries for nearly 20 years later. Before and after in 1955, the rapid development of Japans hydraulic drive, set upin 1956, Hydraulic Industry. Nearly 20 to 30 years, the development of Japans fast hydraulic transmission, a world leader.Hydraulic transmission There are many outstanding

7、 advantages, it is widely used,such as general industr- ial use of plastics processing machinery, the pressure of machinery, machine tools,etc.;operating machineryengineering machinery, constructionmachinery, agricultural machinery,automobiles,etc.;iron and steelindu-stry metallurgical machinery, li

8、fting equipment, such as roller adjustment device; civil water projects with flo- od control and dam gate devices, bed lifts installations, bridges and other manipulation of institutions; speed turbine power plant installations,nuclearpowerplants,etc.;shipfromthedeckheavy machinery (winch), the bow

9、doors, bulkhead valve, stern thruster, etc.; special antenna technology giant with control devices, measu- rement buoys, movements such as rotating stage; military-industrialcontrol devices used in artillery, ship anti- rolling devices, aircraft simulation, aircraft retractable landing gear and rudd

10、er control devices and other devi- ces.A complete hydraulic system consists of five parts, namely, power components, the implementation of co- mponents, control components, auxiliary components and hydraulic oil.The role of dynamic components of the original motive fluid into mechanical energy to th

11、e pressure that the hydraulic system of pumps, it isto power the entire hydraulic system. The structure of the form of hydra- ulic pump gears are generally pump, vane pump and piston pump.Implementation of components (such as hydraulic cylinders and hydraulic motors) which is the pressure of the liq

12、uid can be converted to mechanical energy to drive the load for a straight line reciprocating movement or rotational movement.Control components (that is, the various hydraulic valves) in the hydraulic system to control and regulate the pressure of liquid, flow rate and direction. According to the d

13、ifferent control functions, hydraulic pressure control valve can be divided into valves, flow control valves and directional control valve. Pressurecontrol valves are divided into benefits flow valve (safety valve), pressure relief valve, sequence valve, pressure relays, etc.; flow control valves in

14、cluding throttle, adjusting the valves, flow diversion valve sets, etc.; directional control valve includes a one-way valve , one-way fluid control valve, shuttle valve, valve and so on. Under the control of different ways, can be divided into the hydraulic valve control switch valve, control valve

15、and set the value of the ratio control valve.Auxiliary components, including fuel tanks, oil filters, tubing and pipe joints, seals, pressure gauge, oil level, such as oil dollars.Hydraulic oil in the hydraulic system is the work of the energy transfer medium, there are a variety of mineral oil, emu

16、lsion oil hydraulic molding Hop categories.The role of the hydraulic system is to help humanity work. Mainly by the implementation of components to rotate or pressure into a reciprocating motion.Hydraulic system and hydraulic power control signal is composed of two parts, the signal controlof some p

17、arts of the hydraulic power used to drive the control valve movement. Part of the hydraulic power means thatthecircuitdiagramusedtoshowthedifferentfunctionsofthe interrelationship between components. Containing the source of hydraulic pump, hydraulic motor and auxiliary components; hydraulic control

18、 part contains a variety of control valves, used to control the flow of oil, pressure and direction;operative or hydraulic cylinder with hydraulic motors, according to the actual requirements of their choice.In the analysis and design of the actual task, the general block diagram shows the actual op

19、eration of equi - pment. Hollow arrow indicates the signal flow, while the solid arrows that energy flow.Basic hydraulic circuit of the action sequence - Control components (two four-way valve) and the spring to reset for the implementation of components (double-acting hydraulic cylinder), as well a

20、s the extending and retracting the relief valve opened and closed . For the implementation of componentsand control components,presentationsare based on the corresponding circuit diagram symbols, it also introduced ready made circuit diagram symbols.Working principle of the system, you can turn on a

21、ll circuits to code. If thefirstimplementationofcomponentsnumbered0,thecontrol components associated with the identifier is 1. Out with the implementation of components corresponding to the identifier for the even components, then retracting and implementation of components corresponding to the iden

22、tifier for the odd components. Hydraulic circuit carried out not only to deal with numbers, but also to deal with the actual device ID, in order to detect system failures.DIN ISO1219-2 standard definition of the number of component composition, which includes the following four parts: device ID, cir

23、cuit ID, component ID and component ID. The entire system if only one device, device number may be omitted.Practice, another way is to code all of the hydraulic system components for numbers at this time, components and component code should be consistent with the list of numbers. This method is par

24、ticularly applicable to complex hydraulic control system, each control loop are the corresponding number with the systemWith mechanical transmission, electrical transmission compared to the hydraulic drive has the following advantages:1, a variety of hydraulic components, can easily and flexibly to

25、layout. 2, light weight, small size, small inertia, fast response.3, to facilitate manipulation of control, enabling a wide range of stepless speed regulation (speed range of 2000:1).4, to achieve overload protection automatically.5, the general use of mineral oil as a working medium, the relative m

26、otion can be self-lubricating surface, long service life;6, it is easy to achieve linear motion /7, it is easy to achieve the automation of machines, when the joint control of the use of electro-hydraulic, not only can achieve a higher degree of process automation, and remote control can be achieved

27、.The shortcomings of the hydraulic system:1, as a result of the resistance to fluid flow and leakage of the larger, so less efficient. If not handled properly, leakage is not only contaminated sites, but also may cause fire and explosion.2, vulnerable performance as a result of the impact of tempera

28、ture change, it would be inappropriate in the high or low temperature conditions.3, the manufacture of precision hydraulic components require a higher, more expensive and hence the price.4, due to the leakage of liquid medium and the compressibility and can not be strictly the transmission ratio.5,

29、hydraulic transmission is not easy to find out the reasons for failure; the use and maintenance requirements for a higher level of technology.In the hydraulic system and its system, the sealing device to prevent leakage of the work of media within and outside the dust and the intrusionof foreign bod

30、ies. Seals played the role of components, namely seals. Medium will result in leakage of waste, pollution and environmental machinery and even give rise to malfunctioning machinery and equipment for personal accident. Leakage within the hydraulic system will cause asharp drop in volumetric efficienc

31、y, amounting to less than the required pressure, can not even work. Micro-invasive system of dust particles, can cause or exacerbate friction hydraulic component wear, and further lead to leakage.Therefore,sealsandsealingdeviceisanimportanthydraulic equipment components. The reliability of its work

32、and life, is a measure of the hydraulic system an important indicator of good or bad. In addition tothe closed space, are the use of seals, so that two adjacent coupling surface of the gap between the need to control the liquid can be sealed following the smallest gap. In the contact seal, pressed into self-seal-style and self-styled self-tight seal (ie, sealed lips) two.The three hydraulic system diseases1, as a result of heat transmission medium (hydrauli