With the continuous improvement of production automation, the application of pneumatic technology has expanded rapidly, the varieties and specifications of pneumatic products have continued to increase, the performance and quality have been continuously improved, and the market sales output value has increased steadily. The development trend of pneumatic products is mainly in the following aspects:

 

1、 Miniaturization and integration

 

The limited space requires the overall dimension of pneumatic components to be as small as possible, and miniaturization is the main development trend. Now the minimum cylinder inner diameter is only f2.5, and the switch is equipped; The width of solenoid valve is only 10mm and the effective cross-sectional area is 5mm2; The pressure reducing valve of interface F4 has also been developed. According to the survey, the demand for miniaturized components will double every five years.

 

The integration of air valves not only integrates several valves, but also improves the reliability of maintenance and work.

 

2、 Combination and intelligence

 

The simplest component combination is the cylinder with valve and switch. In material handling, the combination of cylinder, swing cylinder, pneumatic chuck and vacuum suction cup has been used; There is also a combination of moving small items, which is composed of two cylinders with guide according to X and Y axes respectively. It is also equipped with solenoid valve and program controller, which has compact structure, small occupied space and adjustable stroke.

 

3、 Precision

 

In order to make the positioning of the cylinder more accurate, sensors and proportional valves are used to realize feedback control, and the positioning accuracy is up to 0.01mm.

 

In terms of cylinder precision, 0.3mm/s low-speed cylinder and 0.01N small load cylinder are also developed. In air source treatment, a filter with filtration accuracy of 0.01mm, filtration efficiency of 99.9999% and a pressure reducing valve with sensitivity of 0.001mpa have been developed.

 

4、 High speed

 

In order to improve productivity, the pace of automation is accelerating, and high speed is an inevitable trend.

 

At present, the piston speed range of the cylinder is 50-750mm / s. The piston speed of the cylinder is required to be increased to 5m / s, up to 10m / s. According to the survey, after five years, the demand for cylinders with a speed of 2-5M / s will increase by 2.5 times, and the demand for cylinders with a speed of more than 5m / s will increase by 3 times. Accordingly, the response speed of the valve will be accelerated, and the requirement will be increased from the current 1 / 100 second level to 1 / 1000 second level.

 

5、 Oil free, tasteless and sterile

 

Human beings have higher and higher requirements for the environment, so the pneumatic components without oil lubrication will be popularized. Some special industries, such as food, beverage, pharmacy, electronics, etc., have more stringent requirements for air. In addition to oil-free, they also require tasteless and sterile filters. Such filters with special requirements will be continuously developed.

 

6、 High life, high reliability and self diagnosis function

 

The air valve with a service life of 50 million times and the cylinder with a service life of 3000 km have been commercialized, but in textile machinery, there is a high-frequency valve with a service life of more than 100 million times, preferably 200 million times. It is difficult for the existing elastic sealing valve to meet this requirement, which makes the gap sealing element get more attention. Numatics has a kind of air valve, which adopts clearance seal. After ventilation, the valve core is suspended in the valve body, forming friction free movement and self dustproof function. The service life of the valve can exceed 200 million times. Although it is an old product, it is still worth learning from. Pneumatic components are mostly used in automatic production lines. The failure of components often affects the operation of the whole line. The sudden stop of the production line causes serious losses. Therefore, high requirements are put forward for the working reliability of pneumatic components. The pneumatic components required to be supplied by a chemical fiber company in Jiangsu are absolutely reliable within the set service life. They will be replaced whether they can continue to be used or not. This paper also puts forward the problem of life balance of various components, that is, the so-called equal life design. Sometimes, in order to ensure reliable operation, the life index has to be sacrificed. Therefore, the self diagnosis function of pneumatic system has been put on the agenda, and the components and systems with self diagnosis functions such as life prediction are being developed. With the multi-function of mechanical devices, the number of wiring is increasing, which not only increases the workload of installation and maintenance, but also prone to failure and affects the working reliability. Therefore, the improvement of wiring system is also valued by pneumatic components and system designers.

 

7、 Energy saving and low power consumption

 

Energy saving is a permanent topic for enterprises, and will be stipulated in the establishment of ISO14000 environmental protection system standard.

 

The low power consumption of pneumatic components is not only to save energy, but also to be combined with microelectronic technology. The solenoid valve with power consumption of 0.5W has long been commercialized, and the air valves with power consumption of 0.4W and 0.3w have also been developed, which can be directly controlled by PC.

 

8、 Mechatronics

 

In order to accurately achieve the preset control objectives (such as switch, speed, output force, position, etc.), closed-circuit feedback control mode shall be adopted. The conversion between gas and electric signals has become the key to realize closed-circuit control, and the proportional control valve can become the interface of this conversion. It is an important subject for the development of pneumatic technology to develop various forms of proportional control valves and electro-pneumatic proportional / servo systems for a long time in the future, and make them have good performance, reliable operation and low price.

 

Now there are many application examples of proportional / servo system, such as accurate positioning of cylinder; It is used for the suspension system of the vehicle to achieve good vibration damping performance; Automatic tilting device when the cable car turns; Robots serving patients, etc. How to make the above examples more practical and economical needs to be further improved.

 

9、 Meet the special requirements of some industries

 

In the fierce market competition, the development of special pneumatic components for the specific requirements of some industries is an important aspect of developing the market, and all factories pay great attention to it. Recently developed by the domestic pneumatic industry, such as aluminum special cylinder (high temperature resistance and self-locking), railway special cylinder (earthquake resistance and high reliability), rail lubrication special gas valve (low temperature resistance and self filtration capacity), environmental friendly automobile gas system (multi-media and excellent performance), etc.

 

10、 Application of new technologies, processes and materials

 

The technologies of profile extrusion, casting infiltration and module assembly were widely used in China more than ten years ago; New die casting technology (hydraulic core pulling, vacuum die casting, etc.) and new deburring technology (explosion method, electrolysis method, etc.) have been gradually popularized in China; Piezoelectric technology, bus technology, new soft magnetic materials and dialysis membrane are being applied; Superfinishing and nanotechnology will also be transplanted.

 

Scientists and technicians in the pneumatic industry pay special attention to the new trend of seal development. Once seals with new structures and materials appear, they will be adopted.

 

11、 Standardization

 

Implementing standards, especially ISO international standards, is a principle that enterprises must abide by. It has two aspects to do: first, pneumatic products should implement the current standards related to pneumatic, such as terminology, technical parameters, test methods, installation dimensions and safety indicators. The second is that enterprises should establish the assurance system specified in the standards. There are three: quality (ISO9000), environmental protection (ISO14000) and safety (ISO18000). With the continuous addition and revision of standards, enterprises and their products will continue to develop and update. Only in this way can we promote the steady development of pneumatic technology.

 

12、 Security

 

According to the recently issued ISO international standard on pneumatic, the safety requirements for pneumatic components and systems are very strict. According to iso4414 general principles of pneumatics, dangerous elements are divided into 14 categories, mainly including mechanical strength, electrical appliances, noise, control failure, etc. ISO international organization has also issued the ISO18000 standard, which requires enterprises to establish a safety assurance system and put safety issues on a particularly important agenda. Therefore, it is also the general trend of the development of pneumatic technology to consider the safety index in product development and system design. For domestic enterprises, due to the neglect of safety issues in the past industry standards, it is necessary to re evaluate and revise the products that have been put into the market.