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Development trend of hydraulic or pneumatic technology II. The latest hydraulic or pneumatic automation equipment at home and abroad. Industrial application.

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Pneumatic technology is a professional technology that uses compressed air as the medium to drive and control machinery. Because it has the advantages of energy saving, no pollution, high efficiency, low cost, safety and reliability, simple structure and so on. , widely used in various machinery and production lines. In the past, pneumatic systems and their components on production lines such as automobiles and tractors were designed, manufactured and maintained by the factory itself.

The expansion of the application of pneumatic technology is the symbol of the development of pneumatic industry. The application of pneumatic components is mainly in two aspects: maintenance and matching. In the past, the sales of domestic pneumatic components were all used for maintenance, but in recent years, the sales share of direct supporting main components has increased year by year. The application of domestic pneumatic components ranges from metallurgical equipment worth tens of millions of yuan to chairs with only 1 ~ 200 yuan. Specially developed domestic pneumatic components are used for railway turnouts, locomotive wheel rail lubrication, train braking, street cleaning, special workshop lifting equipment and military command vehicles. This shows that pneumatic technology has "penetrated" into all walks of life and is expanding day by day.

Although China's pneumatic industry has reached a certain scale and technical level, it is still far from the international advanced level. The output value of pneumatic products in China only accounts for 1.3% of the world total output value, which is only 1/2 115 in Japan and 1/8 in Germany. This is not commensurate with a big country with a population of 654.38+0 billion. In terms of varieties, a Japanese company has 6,500 varieties, and China only has its 1/5. There is also a big gap between product performance and quality level.

With the pneumatic technology being more and more applied to the automatic assembly and automatic processing of small pieces and special items in various industries, the performance of the original traditional pneumatic components has been continuously improved, and new products have been continuously developed to meet the market demand, which makes the variety of pneumatic components increase day by day. Its development trend mainly includes the following aspects:

Smaller size, lighter weight and lower power consumption. In electronic components, medicine and other manufacturing industries, the size of pneumatic components is bound to be limited because of the small size of the workpiece. Miniaturization and lightweight are the first development direction of pneumatic components. A subminiature solenoid valve with thumb size and effective cross-sectional area of 0.2mm2 has been developed abroad. It is more ideal to develop components with small external dimensions and large flow. Therefore, the valve flow with the same overall size is increased by 2~3.3 times. There are a series of small solenoid valves, the width of which is only 10mm, and the effective area can reach 5mm2. The width is 15mm, and the effective area is 10mm2.

The power consumption of overseas solenoid valves has reached 0.5W, and will be further reduced to adapt to the combination with microelectronics.

Most of the gas source treatment components at home and abroad adopt building block structure, which is not only compact in size, but also convenient for assembly and maintenance.

The positioning accuracy of the actuator is improved, the stiffness is increased, and the piston rod does not rotate, which is more convenient to use. In order to improve the positioning accuracy of cylinder, the application of cylinder with braking mechanism and servo system is more and more common. Even if the air supply pressure and negative load change, the positioning accuracy of the cylinder with servo system can still reach 0.65438 0 mm.

At the international exhibition, there are many cylinders and piston rods with different sections. Because the piston rod can't rotate, this kind of cylinder can maintain a certain accuracy when it is applied to the main engine without additional guiding device. In addition, many cylinders and cylinder sliding assemblies with various guide mechanisms have been developed, such as cylinders with two guide rods and cylinders with double piston rods and double cylinders.

The shape of the cylinder is not limited to circular, but can be square, herringbone or other shapes. The profile is provided with guide grooves, installation grooves for sensors and switches, which is more convenient for users to install and use.

Multifunctional and compound. In order to facilitate users and meet the needs of the market, various small pneumatic systems composed of multiple pneumatic components and equipped with control devices have been developed. For example, an assembly for moving small items consists of two cylinders with guide rails according to the X axis and the Z axis, respectively. The assembly can move 3 kilograms of heavy objects, and is equipped with electromagnetic valve and program controller, with compact structure, small occupied space and adjustable stroke. Another example is a loading and unloading module, which has seven module forms with different functions, and can complete the loading and unloading operation on the precision assembly line, and can combine different modules at will according to the operation content. There is also a kind of manipulator, which is composed of a swinging cylinder and a sucker. It has a small shape and can change the swinging angle. There are several kinds of chucks on the chuck.

Combined with electronic technology, a large number of sensors are used and pneumatic components are intelligent. The cylinder with switch has been widely used in China, the switch volume will be smaller, the performance will be higher, and it can be embedded in the cylinder body; Some also have two-color display, which can show the position error and make the system more reliable. Using sensors instead of flowmeter and pressure gauge can automatically control the flow and pressure of compressed air, save energy and ensure the normal operation of the device. Pneumatic servo positioning system products have entered the market. The system adopts a three-position five-way pneumatic servo valve, compares the predetermined positioning target with the detection data of the position sensor, and implements negative feedback control. When the maximum speed of the cylinder reaches 2m/s and the stroke is 300mm, the positioning accuracy of the system is 0.65438 0 mm.. Japan has successfully trial-produced a new type of intelligent solenoid valve, which is equipped with a logic circuit with a sensor and is the product of the combination of pneumatic components and photoelectric technology. It can directly receive the signal from the sensor, and when the signal meets the specified conditions, it can complete the action by itself without going through an external controller to achieve the control purpose. It has been applied to the conveyor belt of objects, which can identify the size of the transported objects, so that large pieces can be directly transported and small pieces can be diverted.

Higher security and reliability. According to the international standard of pneumatic technology in recent years, the standard not only puts forward the requirement of interchangeability, but also emphasizes safety. The withstand voltage test pressure of pipe joint and gas source treatment shell is increased to 4~5 times of the service pressure, and the withstand voltage time is increased to 5~ 15m.