CN103808457A - Low-temperature vacuum calibration device and method - Google Patents
Low-temperature vacuum calibration device and method Download PDFInfo
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- CN103808457A CN103808457A CN201310724806.0A CN201310724806A CN103808457A CN 103808457 A CN103808457 A CN 103808457A CN 201310724806 A CN201310724806 A CN 201310724806A CN 103808457 A CN103808457 A CN 103808457A
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Abstract
The invention provides a low-temperature vacuum calibration device and method. The low-temperature vacuum calibration device comprises a first pipeline, a calibration room and a low-temperature room, one end of the first pipeline is communicated with the calibration room, the other end of the first pipeline extends into the low-temperature room and is connected with a calibrated vacuum gauge, a temperature control board is arranged inside the low-temperature room, a refrigerator is arranged outside the low-temperature room, a refrigerating head of the refrigerator is connected with the temperature control board in a heat conducting manner, and the calibration room is connected with an air extracting system through a second valve and connected with a standard vacuum gauge. According to the scheme, the internal temperature of the low-temperature room is controlled by the refrigerator and the temperature control board, calibration factors of the calibrated vacuum gauge at needed temperature are obtained and used for calibrating the calibrated vacuum gauge when the calibrated vacuum gauge is used under corresponding temperature conditions, accuracy of the calibrated vacuum gauge is further improved, and measuring uncertainty is reduced.
Description
Technical field
The present invention relates to vacuum measurement technical field, relate in particular to vacuum correction device and method under a kind of low temperature.
Background technology
Vacuum meter is widely used in industrial every field, and the Research on Calibration Technology of vacuum meter is an important research direction in vacuumatic measuring field.Document " Li Zhenghai. the method for compound type vacuum standard calibration vacuum meter. vacuum and low temperature 3(2), 1997 " and the one typical case's calibrating installation and the method that adopt while having introduced current vacuum gauge calibration.The method that complex vacuum standard device has adopted the dynamic and stalic state to combine, is compounded in the method for dynamic comparison, static comparison, three kinds of calibration vacuum meters of static expanding on a vacuum standard, and the calibration range of this device is 10
-4pa~10
5pa, uncertainty is less than 10%.
The weak point of this system is device temperature impact on vacuum meter indicating value while not considering cryogenic applications, can only realize the calibration of vacuum meter under the normal temperature of laboratory.In the time that the vacuum meter being calibrated uses in low temperature environment, can cause larger uncertainty of measurement.
Summary of the invention
Provide hereinafter about brief overview of the present invention, to the basic comprehension about some aspect of the present invention is provided.Should be appreciated that this general introduction is not about exhaustive general introduction of the present invention.It is not that intention is determined key of the present invention or pith, and nor is it intended to limit the scope of the present invention.Its object is only that the form of simplifying provides some concept, using this as the preorder in greater detail of discussing after a while.
The invention provides vacuum correction device and method under a kind of low temperature, while use in low temperature environment in order to solve existing vacuum meter, can cause the problem of larger uncertainty of measurement.
The invention provides vacuum correction device under a kind of low temperature, comprise the first pipeline, calibration chamber and low temperature chamber, one end of described the first pipeline is communicated with described calibration chamber, the other end stretches in described low temperature chamber for being connected by school vacuum meter, in described low temperature chamber, be provided with temperature control plate, described low temperature chamber is outside equipped with refrigeration machine, the refrigeration head of described refrigeration machine is connected with the conduction of described temperature control plate heat, and described calibration chamber is connected with extract system by the second valve, and described calibration chamber is connected with standard vacuum gauge.
The invention provides a kind of calibration factor acquisition methods that adopts vacuum correction device under above-mentioned low temperature, comprise the following steps:
Step 1, will be fixed on the described temperature control plate in described low temperature chamber by school vacuum meter, and be connected with described the first pipeline by school vacuum meter described;
Step 2, open described standard vacuum gauge, and after the stable default duration of described standard vacuum gauge, by extract system, described calibration chamber, low temperature chamber and each pipeline of being connected with described calibration chamber and described low temperature chamber are bled;
Wherein, p is normal pressure, and T is described predetermined temperature, T
1for the residing ambient temperature of described standard vacuum gauge.
Such scheme provided by the invention, by the temperature in refrigeration machine and temperature control plate control low temperature chamber, to obtain the calibration factor under temperature required by school vacuum meter, under corresponding temperature conditions, calibrate during by school vacuum meter described by school vacuum meter with this calibration factor with this, and then improved by school vacuum meter accuracy, reduce the uncertainty of measuring.
Accompanying drawing explanation
Below with reference to the accompanying drawings illustrate embodiments of the invention, can understand more easily above and other objects, features and advantages of the present invention.Parts in accompanying drawing are just in order to illustrate principle of the present invention.In the accompanying drawings, same or similar technical characterictic or parts will adopt same or similar Reference numeral to represent.
The structural representation of vacuum correction device under the low temperature that Fig. 1 provides for the embodiment of the present invention.
Embodiment
Embodiments of the invention are described with reference to the accompanying drawings.The element of describing in an accompanying drawing of the present invention or a kind of embodiment and feature can combine with element and feature shown in one or more other accompanying drawing or embodiment.It should be noted that for purposes of clarity, in accompanying drawing and explanation, omitted expression and the description of unrelated to the invention, parts known to persons of ordinary skill in the art and processing.
The structural representation of vacuum correction device under the low temperature that Fig. 1 provides for the embodiment of the present invention.As shown in Figure 1, vacuum correction device under the low temperature that the embodiment of the present invention provides, comprise the first pipeline, calibration chamber 3 and low temperature chamber 5, one end of the first pipeline is communicated with calibration chamber 3, the other end stretches in low temperature chamber 5 for being connected by school vacuum meter 6, in low temperature chamber 5, be provided with temperature control plate 7, low temperature chamber 5 is outside equipped with refrigeration machine 11, and the refrigeration head of refrigeration machine 11 is connected with temperature control plate 7 heat conduction, calibration chamber 3 is connected with extract system 9 by the second valve 10, and calibration chamber 3 is connected with standard vacuum gauge 8.
Wherein, calibration chamber 3 and low temperature chamber 5 are for having the parts of specific volume size.Low temperature chamber 5 as referred to herein refers to that the temperature of this its inner space can at least be reduced to subzero 50 degrees Celsius, and in general use, the temperature in low temperature chamber 5 can be reduced to subzero 130 degrees Celsius.Heat conduction connection as referred to herein refers to that refrigeration head can carry out heat interchange with temperature control plate 7, in actual use, refrigeration head can directly contact to carry out heat interchange with temperature control plate 7, and refrigeration also can contact to carry out heat interchange by the hot conduction band of flexibility (such as but not limited to copper strips etc.) with temperature control plate 7.Extract system 9 systems can adopt the array mode of turbomolecular pump and the mechanical pump of series connection.Refrigeration machine 11 can adopt sterlin refrigerator.
Such scheme provided by the invention, control the temperature in low temperature chamber by refrigeration machine 11 and temperature control plate 7, to obtain the calibration factor under temperature required by school vacuum meter 6, under corresponding temperature conditions, calibrate during by school vacuum meter 6 described by school vacuum meter 6 with this calibration factor with this, and then improved by school vacuum meter 6 accuracys, reduce the uncertainty of measuring.
Further, calibration chamber logical 3 is crossed micrometering valve 2 and is connected with air supply system 1.Air supply system 1 can be, but not limited to as gas cylinder, the calibration gas of storage certain pressure in gas cylinder.The kind of calibration gas is determined according to actual needs, such as but not limited to adopting nitrogen.Control accurately the calibration gas entering in calibration chamber by micrometering valve, to improve the precision of measurement.
Further, micrometering valve 2 can be, but not limited to ultrahigh vacuum all-metal micrometering valve, adopts ultrahigh vacuum all-metal micrometering valve can improve the control accuracy to calibration gas.
Further, low temperature chamber 5 is formed by stacked the putting of reflection multilayer heat-insulation material.Adopt reflection multilayer heat-insulation material to make low temperature chamber, can improve the insulating power of low temperature chamber 5, prevent temperature leak and cause the poor problem of measurement accuracy to occur.
Further, temperature control plate 7 comprises copper plate, is wound with electrical heating wire on copper plate.Adopt copper plate can improve heat conducting efficiency, improve the efficiency to temperature change in low temperature chamber, heating up at needs is to switch on to improve the temperature of low temperature chamber to electrical heating wire.
The second valve 10 can be, but not limited to ultrahigh vacuum all-metal push-pull valve.
Further, on the first pipeline, be connected with the first valve 4, in the time changing by school vacuum meter, close the first valve 4, be convenient to change operation.
The embodiment of the present invention also provides the calibration factor acquisition methods of vacuum correction device under a kind of low temperature that adopts above-described embodiment, comprises the following steps:
Step 1, will be fixed on the described temperature control plate 7 in described low temperature chamber 5 by school vacuum meter 6, and be connected with described the first pipeline by school vacuum meter 6 described.Can tested vacuum meter 6 be fixed on temperature control plate 7 by clamp.
Step 2, open described standard vacuum gauge 8, and after the stable default duration of described standard vacuum gauge 8, by extract system 9, described calibration chamber 3, low temperature chamber 5 and each pipeline of being connected with described calibration chamber 3 and described low temperature chamber 5 are bled.
In real work, standard vacuum gauge 8 is received in calibration chamber 3, stable default duration, is 24 hours such as but not limited to scheduled duration.By standard vacuum gauge 3 is stablized, can improve measuring accuracy.The standard vacuum gauge 3 is here the vacuum meter after national measurement unit is carried out accurate calibration.This standard vacuum gauge 3 can be selected capacitor thin film type vacuum meter.According to the difference of measuring amount, can select full scale is three capacitor thin film type vacuum meters of 0.02Torr, 10Torr, 1000Torr.The accuracy of measurement of this capacitor thin film type vacuum meter is full scale 0.05%.
Wherein, p is normal pressure, and T is described predetermined temperature, T
1for the residing ambient temperature of described standard vacuum gauge.
Generalized case, the pressure of calibration chamber reaches 1 × 10
-3the Pa order of magnitude, the air pressure after 1 minute in calibration chamber reaches mobile equilibrium, now closes micrometering valve, starts refrigeration machine and temperature control plate, and the temperature in low temperature chamber is adjusted to temperature required.
Can, by repeatedly measuring, obtain the calibration factor under different temperatures, in the time that reality is used, the value being obtained by school vacuum meter 6 is multiplied by calibration factor, is standard value, has improved by introducing calibration factor the precision of measuring, and has reduced the uncertainty of measuring.
In actual use, predetermined vacuum level is less than or equal to 1 × 10
-6pa, to improve the accuracy of measurement.Predetermined temperature is between-130 ℃ to+20 ℃.
Finally it should be noted that: above embodiment only, in order to technical scheme of the present invention to be described, is not intended to limit; Although the present invention is had been described in detail with reference to previous embodiment, those of ordinary skill in the art is to be understood that: its technical scheme that still can record aforementioned each embodiment is modified, or part technical characterictic is wherein equal to replacement; And these modifications or replacement do not make the essence of appropriate technical solution depart from the spirit and scope of various embodiments of the present invention technical scheme.
Claims (10)
1. vacuum correction device under a low temperature, it is characterized in that, comprise the first pipeline, calibration chamber and low temperature chamber, one end of described the first pipeline is communicated with described calibration chamber, the other end stretches in described low temperature chamber for being connected by school vacuum meter, in described low temperature chamber, be provided with temperature control plate, described low temperature chamber is outside equipped with refrigeration machine, the refrigeration head of described refrigeration machine is connected with the conduction of described temperature control plate heat, described calibration chamber is connected with extract system by the second valve, and described calibration chamber is connected with standard vacuum gauge.
2. vacuum correction device under low temperature according to claim 1, is characterized in that, described calibration chamber is connected with air supply system by micrometering valve.
3. vacuum correction device under low temperature according to claim 2, is characterized in that, described micrometering valve is ultrahigh vacuum all-metal micrometering valve.
4. according to vacuum correction device under the low temperature described in claim 1 or 2 or 3, it is characterized in that, described low temperature chamber is formed by stacked the putting of reflection multilayer heat-insulation material.
5. according to vacuum correction device under the low temperature described in claim 1 or 2 or 3, it is characterized in that, described temperature control plate comprises copper plate, on described copper plate, is wound with electrical heating wire.
6. according to vacuum correction device under the low temperature described in claim 1 or 2 or 3, it is characterized in that, described the second valve is ultrahigh vacuum all-metal push-pull valve.
7. according to vacuum correction device under the low temperature described in claim 1 or 2 or 3, it is characterized in that, on described the first pipeline, be connected with the first valve.
8. adopt described in claim 1-7 any one a calibration factor acquisition methods for vacuum correction device under low temperature, it is characterized in that, comprise the following steps:
Step 1, will be fixed on the described temperature control plate in described low temperature chamber by school vacuum meter, and be connected with described the first pipeline by school vacuum meter described;
Step 2, open described standard vacuum gauge, and after the stable default duration of described standard vacuum gauge, by extract system, described calibration chamber, low temperature chamber and each pipeline of being connected with described calibration chamber and described low temperature chamber are bled;
Step 3, be less than or equal to after predetermined vacuum level at described calibration chamber, low temperature chamber and each pipeline vacuum tightness of being connected with described calibration chamber and described low temperature chamber, be filled with calibration gas to described calibration chamber and low temperature chamber, and reach after predetermined value at described calibration chamber pressure, by described refrigeration machine and described temperature control plate, control described low temperature chamber to predetermined temperature, obtain the pressure P of described calibration chamber by described standard vacuum gauge
1, by the described pressure P of being obtained described calibration chamber by school vacuum meter
2; And according to the calibration factor c under predetermined temperature described in following Relation acquisition:
Wherein, p is normal pressure, and T is described predetermined temperature, T
1for the residing ambient temperature of described standard vacuum gauge.
9. method according to claim 8, is characterized in that, described predetermined vacuum level is less than or equal to 1 × 10
-6pa.
10. method according to claim 8 or claim 9, is characterized in that, described predetermined temperature is between-130 ℃ to+20 ℃.
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CN104697670A (en) * | 2015-03-06 | 2015-06-10 | 兰州空间技术物理研究所 | Calibration method for temperature and resistance value of cesium beam tube thermal resistor |
CN105466633A (en) * | 2015-11-18 | 2016-04-06 | 西安航天计量测试研究所 | Pressure sensor calibration device under low temperature |
CN106017742A (en) * | 2016-08-16 | 2016-10-12 | 江苏东方航天校准检测有限公司 | Calibration method for temperature sensor used in vacuum environment |
CN106289666A (en) * | 2016-08-31 | 2017-01-04 | 兰州空间技术物理研究所 | The calibrating installation of a kind of vacuum leak under ambient temperature and method |
CN106441731A (en) * | 2016-08-31 | 2017-02-22 | 兰州空间技术物理研究所 | High-low-temperature vacuum leak hole calibration device and method |
CN108151961A (en) * | 2017-12-08 | 2018-06-12 | 兰州空间技术物理研究所 | A kind of extremely high vacuum calibrating installation and method |
CN108896241A (en) * | 2018-03-22 | 2018-11-27 | 东莞市鼎力自动化科技有限公司 | A kind of vacuum degree measurement system and method |
CN108956007A (en) * | 2017-05-23 | 2018-12-07 | 成都飞机工业(集团)有限责任公司 | A kind of vacuum meter on-line calibration room |
CN109404322A (en) * | 2018-12-06 | 2019-03-01 | 北京东方计量测试研究所 | A kind of wide-range high-precision molecular pump pumping speed test macro and method |
CN113532735A (en) * | 2021-07-12 | 2021-10-22 | 北京卫星环境工程研究所 | Vacuum sensor high-low temperature working condition calibration device adopting bath oil for temperature control |
CN114526863A (en) * | 2022-01-27 | 2022-05-24 | 中国科学院合肥物质科学研究院 | Ultralow temperature vacuum measurement calibration device and method based on GM refrigerator cooling |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100805926B1 (en) * | 2006-08-22 | 2008-02-21 | 한국표준과학연구원 | Integral calibration apparatus for low vacuum gauge and high vacuum gauge |
WO2009012605A2 (en) * | 2007-07-23 | 2009-01-29 | Inficon Gmbh | Method for calibrating and operating a measuring cell arrangement |
CN102589803A (en) * | 2012-02-06 | 2012-07-18 | 江苏东方航天校准检测有限公司 | Portable multifunctional vacuum calibration system and method |
CN102944358A (en) * | 2012-11-12 | 2013-02-27 | 中国航天科技集团公司第五研究院第五一〇研究所 | High and low temperature vacuum calibrating device and method |
-
2013
- 2013-12-24 CN CN201310724806.0A patent/CN103808457B/en not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100805926B1 (en) * | 2006-08-22 | 2008-02-21 | 한국표준과학연구원 | Integral calibration apparatus for low vacuum gauge and high vacuum gauge |
WO2009012605A2 (en) * | 2007-07-23 | 2009-01-29 | Inficon Gmbh | Method for calibrating and operating a measuring cell arrangement |
CN102589803A (en) * | 2012-02-06 | 2012-07-18 | 江苏东方航天校准检测有限公司 | Portable multifunctional vacuum calibration system and method |
CN102944358A (en) * | 2012-11-12 | 2013-02-27 | 中国航天科技集团公司第五研究院第五一〇研究所 | High and low temperature vacuum calibrating device and method |
Non-Patent Citations (1)
Title |
---|
冯焱等: "现场真空校准装置的设计", 《真空与低温》 * |
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CN104697670B (en) * | 2015-03-06 | 2017-06-13 | 兰州空间技术物理研究所 | A kind of scaling method of cesium beam tube thermistor temp and resistance |
CN104697670A (en) * | 2015-03-06 | 2015-06-10 | 兰州空间技术物理研究所 | Calibration method for temperature and resistance value of cesium beam tube thermal resistor |
CN105466633A (en) * | 2015-11-18 | 2016-04-06 | 西安航天计量测试研究所 | Pressure sensor calibration device under low temperature |
CN105466633B (en) * | 2015-11-18 | 2018-10-16 | 西安航天计量测试研究所 | A kind of low temperature lower pressure sensor calibrating installation |
CN106017742A (en) * | 2016-08-16 | 2016-10-12 | 江苏东方航天校准检测有限公司 | Calibration method for temperature sensor used in vacuum environment |
CN106289666B (en) * | 2016-08-31 | 2020-03-06 | 兰州空间技术物理研究所 | Calibration device and method for vacuum leak at ambient temperature |
CN106441731A (en) * | 2016-08-31 | 2017-02-22 | 兰州空间技术物理研究所 | High-low-temperature vacuum leak hole calibration device and method |
CN106289666A (en) * | 2016-08-31 | 2017-01-04 | 兰州空间技术物理研究所 | The calibrating installation of a kind of vacuum leak under ambient temperature and method |
CN108956007A (en) * | 2017-05-23 | 2018-12-07 | 成都飞机工业(集团)有限责任公司 | A kind of vacuum meter on-line calibration room |
CN108151961A (en) * | 2017-12-08 | 2018-06-12 | 兰州空间技术物理研究所 | A kind of extremely high vacuum calibrating installation and method |
CN108151961B (en) * | 2017-12-08 | 2020-02-07 | 兰州空间技术物理研究所 | Extreme high vacuum calibration device and method |
CN108896241A (en) * | 2018-03-22 | 2018-11-27 | 东莞市鼎力自动化科技有限公司 | A kind of vacuum degree measurement system and method |
CN108896241B (en) * | 2018-03-22 | 2021-07-06 | 东莞市鼎力自动化科技有限公司 | Vacuum degree detection system and method |
CN109404322A (en) * | 2018-12-06 | 2019-03-01 | 北京东方计量测试研究所 | A kind of wide-range high-precision molecular pump pumping speed test macro and method |
CN113532735A (en) * | 2021-07-12 | 2021-10-22 | 北京卫星环境工程研究所 | Vacuum sensor high-low temperature working condition calibration device adopting bath oil for temperature control |
CN114526863A (en) * | 2022-01-27 | 2022-05-24 | 中国科学院合肥物质科学研究院 | Ultralow temperature vacuum measurement calibration device and method based on GM refrigerator cooling |
CN114526863B (en) * | 2022-01-27 | 2022-10-14 | 中国科学院合肥物质科学研究院 | Ultralow temperature vacuum measurement calibration device and method based on GM refrigerator cooling |
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