1、 Hydraulic System Hydraulic 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 Braman ,1749-1814
2、), 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. After the World War I (1914-1918) ,because of the extensive application of hydraulic transmission, espec- ial
3、ly after 1920, more rapid development. Hydraulic components in the late 19th century about the early 20th century, 20 years, only started to enter the formal phase of industrial production. 1925 Vickers (F. Vikers) the invention of the pressure balanced vane pump, hydraulic components for the modern
4、 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 converter,
5、 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 Europe and the United States a
6、nd other countries for nearly 20 years later. Before and after in 1955, the rapid development of Japans hydraulic drive, set up in 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 machinery engineering machinery, construction machinery, agricultural machinery, automobiles, etc.； iron and steel indu- stry metallurgical mac
8、hinery, lifting 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 1 plant installations, nuclear power plants, etc.； ship from the deck heavy machin
9、ery (winch), the bow doors, bulkhead valve, stern thruster, etc.； special antenna technology giant with control devices, measu- rement buoys, movements such as rotating stage； military-industrial control devices used in artillery, ship anti- rolling devices, aircraft simulation, aircraft retractable
10、 landing gear and rudder 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
11、 mechanical energy to the pressure that the hydraulic system of pumps, it is to 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
12、is the pressure of the liquid 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 di
13、rection. According to the different control functions, hydraulic pressure control valve can be divided into valves, flow control valves and directional control valve. Pressure control valves are divided into benefits flow valve (safety valve), pressure relief valve, sequence valve, pressure relays,
14、etc.； flow control valves including 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
15、switch valve, control valve 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
16、 a variety of mineral oil, emulsion 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 control of some parts of the hydraulic power used to drive the control valve movement.
