Abstract: This paper summarizes the development and current status of vortex oil-free vacuum pump technology, including the development of vortex technology to the application of vortex technology in various industries; from the principle of vortex oil-free vacuum pump to vortex oil-free vacuum pump Manufacturing technology and technical indicators; from the development of vortex vacuum pumps in various countries around the world to the development status of vortex vacuum pumps in China, there is a systematic introduction to the status of vortex oil-free vacuum pumps.
1 Introduction
The concept of vortex is quite long, and in the early 20th century there was already a patent for vortex technology in the world. However, due to the limitations of the technical level at the time, the scroll mechanism could not be manufactured, and the concept of the vortex was forgotten. In 1973, the scroll mechanism was re-launched and the first model mechanism was created, making the practical application of this technology possible. The high reliability, stable operation, extremely low noise, energy saving and other potentials of the scroll mechanism immediately attracted the attention and urgent needs of the refrigerator industry. They were favored by industry leaders and quickly put into industrial application. The scroll compressor technology and products of famous companies such as Trance, Hitachi and Copland have led the wave of practical application of the world vortex technology, which has promoted technological advancement and product upgrading in many industries such as refrigerators and air conditioners.
Today, the vortex technology has been extended to the vacuum pump manufacturing industry from the initial application in the compressor industry, realizing the practical application of the vortex cleaning vacuum technology that is completely oil-free, smoother in operation, lower in noise, and more energy-saving. People apply the concept and principle of vortex to produce a single-stage, two-stage vortex oil-free vacuum pump series which is not polluting the vacuum application equipment and environment, and whose pumping speed, life and energy consumption are better than ordinary oil pumps.
In the early 1990s, the world's first scroll vacuum pump was introduced to the market, and vortex technology began to be promoted and applied worldwide as a new vacuum acquisition technology. So far, the world's manufacturers of scroll vacuum pumps are concentrated in the United States, Japan and Europe, represented by Anest1wata in Japan, Varian in the United States, and Bush in Germany. The products are included in the 0.25L/S-1OL/S series, and some products with 15L/S or larger pumping capacity are also in the experimental stage.
2. Characteristics and application fields of 0-Ifree scroll vacuu pump
A clean vacuum environment has always been the ideal vacuum environment pursued by scientists and businesses. Since the creation of a vacuum environment, people have tried to achieve a clean vacuum by different means. Today, clean vacuum equipment has evolved into condensate pumps, column pumps, claw pumps, scroll pumps, and diaphragm pumps. Among the existing oil-free vacuum pumps, the vortex oil-free vacuum pump has the characteristics of stable operation, low noise, energy saving, light weight and small volume compared with other types of oil-free vacuum pumps, and has been widely applied to the following scientific research. And production areas: 1 semiconductor industry - thin film preparation equipment, semiconductor device packaging equipment; 2 vacuum metallurgy industry - vacuum furnace, nano material preparation equipment, vacuum testing equipment; 3 scientific instrument industry - synchrotron radiation beam line, electron microscope, Analytical test equipment; 4 medical equipment - dental equipment, dialysis machine; 5 biological products industry - material purification, drug preparation; 6 packaging industry - food, medicine, biological products and other packaging equipment.
3, vortex oil-free vacuum pump working principle, technical indicators and comparison with ordinary oil pumps
The scroll of the vortex oil-free vacuum pump is one or a plurality of involute spirals which are connected to one plane at one end to form a scroll-shaped disc structure. A pair of scrolls consisting of a fixed scroll and an orbiting scroll constitutes a basic pumping mechanism for the vortex oil-free vacuum. For example, in a two-stage scroll oil-free vacuum pump, there are two fixed scrolls corresponding to one direction, and one rotating scroll between two scrolls. The relative motion of the moving and stationary scrolls forms a crescent-shaped vacuum chamber whose volume changes continuously, so that the gas is sucked from the suction port, the exhaust port is exhausted, and the exhaust cycle is completed.
It is well known that the Oilfree scrolI vacuum pump has significant characteristics compared to conventional oil vacuum pumps. Take the ordinary rotary vane vacuum pump as an example to illustrate the difference:
Table 1 Comparison of technical indexes between vortex oil-free vacuum pump and ordinary direct-coupled rotary vane vacuum pump
Technical Specifications Rotary Oil Vacuum Pump Vortex Oil Free Vacuum Pump
Pumping speed (l/s) 2.0, 4.0, 82.0, 4.4, 8.7
Ultimate vacuum (Pa) 0.6 1.0
Service life (h) 40000 40000
Overhaul interval (h) 8000 10000
Cooling medium oil air
Noise (dB) 7560
Quality (kg) 7041
Number of motor phases 31
Voltage (V) 220/380 220
Power (kw) 1.1 0.6
Number of revolutions (r/min) 1400 1437
4, the advantages of vortex oil-free vacuum pump and its problems can be solved for users
4.1 vortex oil-free vacuum pump superior performance
The main advantages of the scroll vacuum pump are the small gap, less leakage, high compression ratio, stable pumping speed in a wide range of force, and wide working pressure range. The driving torque variation is small, the power variation is small, the vibration noise is low, and the reliability is high. This is not available with other types of dry vacuum pumps.
4.2 Vortex oil-free vacuum pump solves the basic and common problems of pollution and vibration
Due to oil leakage, noise, oil return pollution, high energy consumption and vibration of ordinary rotary vane oil pumps, the user has adverse effects, such as oil vapor pollution in the biological products industry and the semiconductor industry, and the process system return valve problem. In the coating process of vacuum coating equipment, when coating under vacuum conditions of 20~40Pa, if the ordinary rotary vane mechanical vacuum pump is used as the pre-stage vacuum pump, it will cause pollution to the coating process equipment and affect the film formation amount. In the semiconductor wafer manufacturing process, the use of the oil pump has a yield difference of 509l compared to the use of the dry pump, and the discharged oil mist vapor is also polluted to the environment. In the scientific instrument industry, especially in the analytical test instrument industry, the use of oil pumps will have an adverse effect on the test results. The role of the vortex oil-free vacuum pump for the large-scale synchrotron beam line as the fore-stage vacuum pump is also quite obvious. In addition, the vortex oil-free vacuum pump eliminates the environmental pollution and troubles caused by the oil leakage of the ordinary oil pump.
4.3 Vortex oil-free vacuum pump reduces the system manufacturing and operation cost to prevent the oil return pollution of the vacuum system from the ordinary rotary vane oil vacuum pump. It is necessary to add a cold trap to capture oil molecules in the pumping system; Cleaning and degreasing; some need to replace the vacuum pump oil regularly. The vortex oil-free vacuum pump first requires no oil trap mechanism such as a cold trap, the second does not need to change the vacuum pump oil, the third vibration is smaller, the operation is more stable, the fourth energy consumption is reduced, and the fifth weight is lighter. Six breakthroughs in the scope of use of the oil pump, the above advantages make the vortex oil-free vacuum pump become a replacement product of the ordinary rotary oil vacuum pump.
5, the conclusion
In the manufacturing process represented by the semiconductor and electronics industries, and in the scientific research and analysis and testing industry, there is an urgent need for a clean vacuum environment without oil pollution, but clean vacuum obtaining equipment such as condensate pumps, column pumps, claw pumps, scroll pumps, and Diaphragm pumps and the like have not yet formed reliable and advanced batch domestic products. The imported vortex oil-free vacuum pump is a new product that has been officially launched in China for less than three years. Due to the aforementioned price, market development and user awareness, there is no virtuous circle. In this way, on the one hand, there is an urgent market demand. On the other hand, there is no suitable product from the perspective of price and technology, which has caused a huge market gap.
There is no doubt that the volute oil-free vacuum pump with moderate price and reliable performance will become the mainstream for the products demanded by the Chinese market. It is imperative to vigorously develop the rotary oil-free vacuum pump. The development of vortex and other oil-free vacuum pump series products and their testing techniques in line with the requirements of the Chinese market has also become an opportunity for China Vacuum to gain further development in the industry.
In order to solve the basic and common problems in the scientific research and the development of new materials, semiconductors and other industries in China, in recent years, experts in the industry have introduced the vortex oil-free vacuum pump technology and its development status to the domestic market. The development of vacuum pump manufacturers and agents in the Chinese market has led to an increase in sales in the Chinese market. Domestic vacuum industry-related enterprises have also carried out various stages of exploration, such as basic, applied research and small-scale trial production of vortex oil-free vacuum pump production. However, due to technical infrastructure, incentive mechanism, research and development methods, and capital investment restrictions, research and development work is not very fast. .
Product quality, stability and reliability, as well as technology promotion and market development planning, principles, and means are also problems. Therefore, the next industrialization technology research and development and market development of the vortex oil-free vacuum pump series products are two major problems that enterprises must solve. With the development of research and development methods, capital investment, and market development problems, the vortex oil-free vacuum pump will open the market, thereby improving the overall vacuum to obtain the technical level of the industry. The successful vortex oil-free vacuum pump series product development and market development model will also provide effective reference for other clean vacuum obtaining equipment in China such as condensate pump, sample wall, and claw-type diaphragm pump.
AOM (Acousto-optic Modulator)
|
It belongs to the high-speed acousto-optic Pulse Modulator which realizes the intensity modulation over the Laser according to the inputted pulse signal and gets corresponding digitally coded optical signal by inputting the digital signal of different codes and frequencies (TTL/ Analog) into the driving power supply of modulator. It is mainly used in such fields as laser text-image processing and laser digital communication.
This product has such characteristics as quick modulation rate, small volume, high efficiency, high extinction ratio, easy coding and convenient use.
|
|
Wavelength
|
400-750nm
|
|
|
Optical Power
|
Typical <1W (@1.0nm)
|
35(L) x 21 (W) x 24(H) cm^3, 0.04kg
|
|
Transmission
|
93%
|
|
Center Frquency
|
100MHz
|
|
Diffraction efficiency
|
75%
|
|
Active Aperture
|
1.0 mm
|
|
Extinction Ratio
|
1000:1
|
|
Pulse repectition frequency
|
1MHz
|
|
RF power
|
1.5W
|
|
Input impedance
|
50Ω
|
|
Controller Drive Voltage
|
24VDC
|
|
External Modulatioin
|
TTL / Analog
|
Note: Contact us for high pulse repetition frequency AOM.
Shutter
|
Cost-effective mechanical shutter, with repetition rate maximum 10 Hz. The valid output power is up to 3W available. The rise and fall time can be lower to 0.7 ms. Delay time is minimum 5 ms.
|
Operating Frequency Range
|
0-10Hz
|
Shutter-i
|
|
Maximum Laser Power
|
<3W
|
74(L) x 45(W) x 49.5(H) mm^3, 0.1kg
|
|
Minimum Exposure Pulse
|
5ms
|
|
Rise Time
|
~1.5ms
|
|
Fall TIme
|
~1.5ms
|
|
Jitter (@10Hz)
|
5ms (Typical)
10ms (Max)
|
|
Delay d
|
5ms
|
|
Operating Temperature
|
15~40 ℃
|
|
External Modelation
|
TTL
|
|
Drive Voltage
|
5VDC / 12VDC
|
d: Delat between input pulse rising edge and initialization of shutter opening
AOM And Shutter
Pulse Modulator,Pulse Width Modulation,Pulse Frequency Modulation
Changchun New Industries Optoelectronics Technology Co., Ltd. , https://www.opticsqm.com