CN211291867U - Dynamic calibration device for vacuum gauge - Google Patents
Dynamic calibration device for vacuum gauge Download PDFInfo
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- CN211291867U CN211291867U CN201922006172.0U CN201922006172U CN211291867U CN 211291867 U CN211291867 U CN 211291867U CN 201922006172 U CN201922006172 U CN 201922006172U CN 211291867 U CN211291867 U CN 211291867U
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Abstract
The utility model provides a dynamic calibration device of a vacuum gauge, which comprises a movable frame, a PLC controller and a calibration structure, wherein the PLC controller and the calibration structure are both fixed on the movable frame, and the calibration structure is connected with the PLC controller; the utility model uses the standard vacuum sensor to detect the vacuum degree in the vacuum chamber, sets the vacuum back-lifting device, the vacuum pumping device is matched with the vacuum stabilizing unit, and uses the PLC controller to control the vacuum back-lifting device and the vacuum pumping device to work according to the vacuum degree detected by the standard vacuum sensor, so that the vacuum stabilizing unit can change the working state of the vacuum back-lifting device and the vacuum pumping device according to the vacuum degree in the vacuum chamber; meanwhile, an analog input/output module is arranged, so that the rapid detection of the detected sensor is realized; this device is with the stability control of vacuum value within 2%, need not connect nitrogen gas in addition and destroys the vacuum, has greatly improved the convenience.
Description
Technical Field
The utility model relates to a high-density detection area especially indicates a vacuum gauge developments calibrating device.
Background
The vacuum gauge is an instrument for measuring atmospheric pressure in an absolute pressure state, and is widely applied to various fields of war industry, electronics, medical food, electric power, metallurgy, chemical engineering and the like; with the development of science and technology, the requirement for the detection of the vacuum gauge in the industry is continuously improved, and as the vacuum gauge is used for the detection of a field vacuum system, and the whole set of vacuum system cannot work normally when the vacuum gauge is removed, the requirement for the field calibration of the vacuum gauge is more and more urgent, which will become the development trend of the calibration of the vacuum gauge in the future;
the existing vacuum gauge calibration device usually performs measurement calibration work by a static expansion method and a dynamic contrast method, wherein the dynamic contrast method generally utilizes a combination of a pre-vacuum pump and a molecular pump set to evacuate a calibration chamber to a limit vacuum, and then nitrogen is injected into the calibration chamber through a micro-adjustment device to obtain a target vacuum degree, so that accurate calibration of a calibrated vacuum gauge is realized.
SUMMERY OF THE UTILITY MODEL
The utility model provides a vacuum gauge dynamic calibration device, through using standard vacuum sensor to detect the vacuum in the vacuum storehouse, setting up vacuum back-lifting device, vacuum supplement pumping device and vacuum stabilization unit cooperation, use PLC controller according to the vacuum control vacuum back-lifting device that standard vacuum sensor detected, vacuum supplement pumping device work, make vacuum stabilization unit can change the operating condition of vacuum back-lifting device, vacuum supplement pumping device according to the vacuum in the vacuum storehouse; meanwhile, an analog input/output module is arranged, so that the rapid detection of the detected sensor is realized; this device passes through the effect of vacuum stabilization unit, can make the stability control of device within 2%, and the equipment in this application need not connect nitrogen gas in addition and destroy the vacuum, has greatly improved the convenience.
The technical scheme of the utility model is realized like this:
a vacuum gauge dynamic calibration apparatus, comprising: the PLC calibration device comprises a moving frame, a PLC controller and a calibration structure, wherein the PLC controller and the calibration structure are fixed on the moving frame, and the calibration structure is connected with the PLC controller;
the calibration structure comprises a vacuum pump and a vacuum bin, and the vacuum pump is communicated with the vacuum bin;
the calibration structure further comprises a vacuum supplement pumping device, a vacuum stabilizing unit and a vacuum back-lifting device which are sequentially connected in series;
the vacuum compensation pumping device, the vacuum stabilizing unit and the vacuum back-lifting device are connected in series and then are connected in parallel with a pipeline communicated with the vacuum pump and the vacuum bin;
the vacuum pump is connected with a vacuum pump motor;
the vacuum pump and the vacuum pump motor are both arranged on the movable frame;
a fan is arranged on the movable frame;
and the vacuum pump motor, the vacuum compensation pumping device, the vacuum return lifting device, the vacuum stabilizing unit and the fan are all connected with the PLC.
Further, an exhaust capillary tube for controlling the pressure difference of the vacuum calibration pump is arranged in the vacuum stabilization unit, a first electromagnetic valve for controlling the on-off of the exhaust capillary tube and the vacuum pumping device is installed at one end of the exhaust capillary tube, a second electromagnetic valve for controlling the on-off of the exhaust capillary tube and the atmosphere is installed at the other end of the exhaust capillary tube, and the exhaust capillary tube is normally connected with the vacuum pumping device.
Further, the exhaust capillary tube is provided with one or more than one.
Furthermore, a first vacuum bent joint and a second vacuum bent joint are arranged on the vacuum bin, the first vacuum bent joint is connected with a standard vacuum sensor used for detecting the vacuum degree value in the vacuum bin, and the second vacuum bent joint is connected with a calibrated vacuum sensor;
and the standard vacuum sensor is connected with the PLC.
Further, a special vacuum valve is installed on the first vacuum elbow joint, and the standard vacuum sensor is communicated with the vacuum bin through the special vacuum valve;
the special vacuum valve is connected with the PLC.
Further, a vacuum calibration valve is arranged on the second vacuum elbow joint, and the calibrated vacuum gauge is communicated with the vacuum bin through the vacuum calibration valve;
the vacuum calibration valve is connected with the PLC.
Furthermore, an analog quantity input/output module is arranged in the PLC, a port which is suitable for different output signals is arranged on the analog quantity input/output module, and the port is used for inputting/outputting current, voltage and frequency signals;
the port is connected to a vacuum sensor to be tested.
Further, the output end of the vacuum pump is connected with a two-way electromagnetic valve I, and a two-way electromagnetic valve II is arranged on a pipeline between the two-way electromagnetic valve I and the vacuum bin;
and the vacuum compensation pumping device, the vacuum stabilizing unit and the vacuum back-lifting device are connected in series and then are connected with the two-way electromagnetic valve II in parallel.
Further, the second vacuum elbow is provided with one or more, and correspondingly, the vacuum calibration valve is provided with one or more.
Furthermore, a vacuum pump handle is arranged on the vacuum pump.
The vacuum degree in the vacuum bin is detected by using a standard vacuum sensor, the vacuum back-lifting device is arranged, the vacuum supplement pumping device is matched with the vacuum stabilizing unit, and the PLC is used for controlling the vacuum back-lifting device and the vacuum supplement pumping device to work according to the vacuum degree detected by the standard vacuum sensor, so that the vacuum stabilizing unit can change the working states of the vacuum back-lifting device and the vacuum supplement pumping device according to the vacuum degree in the vacuum bin; meanwhile, an analog input/output module is arranged, so that the rapid detection of the detected sensor is realized; this device passes through the effect of vacuum stabilization unit, can make the stability control of device within 2%, and the equipment in this application need not connect nitrogen gas in addition and destroy the vacuum, has greatly improved the convenience.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for a customer of ordinary skill in the art, other drawings can be obtained according to these drawings without inventive labor.
Fig. 1 is a schematic diagram of an overall structure of a dynamic calibration apparatus for a vacuum gauge according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of an internal structure of the dynamic calibration apparatus for a vacuum gauge shown in fig. 1 with a stabilizing unit 5.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
In an embodiment of the present invention, see fig. 1-2, a vacuum gauge dynamic calibration apparatus comprises: the device comprises a moving frame 1, a PLC (programmable logic controller) 8 and a calibration structure, wherein the PLC 8 and the calibration structure are fixed on the moving frame 1, and the calibration structure is connected with the PLC 8;
the calibration structure comprises a vacuum pump 2 and a vacuum bin 7, wherein the vacuum pump 2 is communicated with the vacuum bin 7;
the calibration structure also comprises a vacuum supplement pumping device 4, a vacuum stabilizing unit 5 and a vacuum back-lifting device 6 which are sequentially connected in series;
the vacuum supplementary pumping device 4, the vacuum stabilizing unit 5 and the vacuum back-lifting device 6 are connected in series and then are connected in parallel with a pipeline communicated with the vacuum pump 2 and the vacuum bin 7;
the vacuum pump 2 is connected with a vacuum pump motor 3;
the vacuum pump 2 and the vacuum pump motor 3 are both arranged on the movable frame 1;
the movable frame 1 is provided with a fan 11;
the vacuum pump motor 3, the vacuum compensation device 4, the vacuum back-lifting device 6, the vacuum stabilizing unit 5 and the fan 11 are all connected with the PLC 8.
In the embodiment of the present invention, see fig. 1-2, an exhaust capillary 53 for controlling the pressure difference of the vacuum calibration pump is provided in the vacuum stabilization unit 5, a first electromagnetic valve 51 for controlling the on-off between the exhaust capillary 53 and the vacuum pumping device 4 is installed at one end of the exhaust capillary, a second electromagnetic valve 52 for controlling the on-off between the exhaust capillary 53 and the atmosphere is installed at the other end of the exhaust capillary 53, and the exhaust capillary 53 is connected to the vacuum pumping device 6.
In an embodiment of the present invention, see fig. 1-2, the exhaust capillary 53 is provided with one or more tubes.
In the embodiment of the present invention, as shown in fig. 1-2, the vacuum chamber 7 is provided with a first vacuum elbow 71 and a second vacuum elbow 72, the first vacuum elbow 71 is connected to a standard vacuum sensor 712 for detecting the vacuum degree in the vacuum chamber, and the second vacuum elbow 72 is connected to a calibrated vacuum sensor;
the standard vacuum sensor 712 is connected to the PLC controller 8.
In the embodiment of the present invention, as shown in fig. 1-2, a special vacuum valve 711 is installed on the first vacuum elbow 71, and the standard vacuum sensor 712 is communicated with the vacuum chamber 7 through the special vacuum valve 711;
the dedicated vacuum valve 711 is connected to the PLC controller 8.
In the embodiment of the present invention, as shown in fig. 1-2, the second vacuum elbow 72 is provided with a vacuum calibration valve 721, and the calibrated vacuum gauge is communicated with the vacuum chamber 7 through the vacuum calibration valve 721;
the vacuum calibration valve 721 is connected to the PLC controller 8.
In the embodiment of the present invention, as shown in fig. 1-2, an analog input/output module 81 is disposed in the PLC controller 8, and a port adapted to different output signals is disposed on the analog input/output module 81, and the port is used for inputting/outputting current, voltage and frequency signals;
the port is connected to a vacuum sensor to be tested.
In the specific embodiment of the present invention, as shown in fig. 1-2, the output end of the vacuum pump 2 is connected to a two-way electromagnetic valve one 21, and a two-way electromagnetic valve two 22 is arranged on the pipeline between the two-way electromagnetic valve one 21 and the vacuum chamber 7;
the two-way electromagnetic valve I21 is used for preventing air from entering the vacuum pump 2 and ensuring the tightness of the vacuum pump 2;
the vacuum supplement pumping device 4, the vacuum stabilizing unit 5 and the vacuum back-lifting device 6 are connected in series and then are connected in parallel with the two-way electromagnetic valve II 22.
In a specific embodiment of the present invention, as shown in fig. 1-2, the first vacuum elbow 71 is provided with one or more and the second vacuum elbow 72 is provided with one or more.
In the embodiment of the present invention, as shown in fig. 1-2, a vacuum pump handle 23 is disposed on the vacuum pump 2.
In the embodiment of the present application, as shown in fig. 1-2, the vacuum pumping device 4 is a vacuum capillary, and the vacuum pumping device 6 is also a vacuum capillary.
In the specific embodiment of the present invention, as shown in fig. 1-2, during operation, a vacuum gauge to be detected is connected to the vacuum chamber 7 through the vacuum calibration valve 721 on the second vacuum elbow 72, first a plurality of target vacuum degrees are input into the PLC controller 8, then the switch on the PLC controller 8 is turned on, and the vacuum pump motor 3, the vacuum pumping device 4, the vacuum stabilizing unit 5 and the vacuum pumping device 6 start to operate;
in the regulation and control process, the vacuum stabilizing unit 5, the vacuum pumping device 4 and the vacuum pumping device 6 are matched with each other to detect the vacuum degree in the vacuum chamber 7 and transmit a detection value to the PLC 8, when the vacuum degree value in the vacuum chamber 7 reaches a target set value, the vacuum calibration valve 721 is opened to detect the target vacuum degree value of the detected vacuum gauge, and after one vacuum degree value is detected, the vacuum calibration valve 721 is closed;
because a plurality of vacuum degree values are set in the PLC controller 8 in advance, a plurality of target vacuum degree values can be continuously detected, meanwhile, an analog input/output module 81 is arranged in the PLC controller 8, after the first vacuum degree value test is finished, the PLC controller 8 automatically tests the next target vacuum degree value, and the calibration process is the same as the process;
can know through the attached drawing and the aforesaid, the vacuum gauge dynamic calibration device in this application need not connect nitrogen gas and destroys the vacuum degree in the vacuum chamber 7, and the operation is simple swift more, has further improved the stability of regulation and control in-process.
In the specific embodiment of the present invention, see fig. 1-2, the device has three modes at the time of operation, specifically as follows:
firstly, when the working vacuum degree value is larger than the target vacuum degree value, the vacuum degree value is reduced by entering a rough pumping state, at the moment, the PLC 8 controls the two-way electromagnetic valve I21 and the two-way electromagnetic valve II 22 to be opened, the first electromagnetic valve 51 and the second electromagnetic valve 52 to be closed, and the vacuum pump 2 is communicated with the vacuum bin 7 to realize rapid vacuum pumping;
secondly, when the vacuum degree value in the vacuum chamber 7 detected by the standard vacuum sensor 712 is close to the target vacuum degree value, entering a fine pumping state, and continuing to reduce the vacuum degree value, at this time, the PLC controller 8 controls the two-way electromagnetic valve two 22 to be closed, the first electromagnetic valve 51 to be opened, and the second electromagnetic valve 52 to be closed, and at this time, the vacuum pumping device 4 works to reduce the air amount in the vacuum chamber 7, so as to reduce the vacuum degree value in the vacuum chamber 7;
thirdly, when the working vacuum degree value is smaller than the target vacuum degree value, the vacuum degree value is increased, the standard vacuum sensor 712 transmits the detected vacuum degree value in the vacuum chamber 7 to the PLC controller 8, the PLC controller 8 controls the second electromagnetic valve 52 to be opened, the first electromagnetic valve 51 and the two-way electromagnetic valve 22 to be closed, and at the moment, the vacuum back-lifting device 6 works to increase the air amount in the vacuum chamber 7, so that the vacuum degree value in the vacuum chamber 7 is increased.
In the embodiment of the present invention, referring to fig. 1-2, the vacuum degree in the vacuum chamber 7 is detected by using the standard vacuum sensor 712, the vacuum pumping device 6 is set, the vacuum pumping device 4 is matched with the vacuum stabilizing unit 5, and the PLC controller 8 is used to control the vacuum pumping device 6 and the vacuum pumping device 4 to work according to the vacuum degree detected by the standard vacuum sensor 712, so that the vacuum stabilizing unit 5 can change the working states of the vacuum pumping device 4 and the vacuum pumping device 6 according to the vacuum degree in the vacuum chamber 7; meanwhile, an analog quantity input/output module 81 is arranged, so that the rapid detection of the detected sensor is realized; this device passes through the effect of vacuum stabilization unit 5, can make the stability control of device within 2%, and the equipment in this application need not connect nitrogen gas in addition and destroy the vacuum, has greatly improved the convenience.
The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A vacuum gauge dynamic calibration apparatus, comprising: the PLC calibration device comprises a moving frame, a PLC controller and a calibration structure, wherein the PLC controller and the calibration structure are fixed on the moving frame, and the calibration structure is connected with the PLC controller;
the method is characterized in that: the calibration structure comprises a vacuum pump and a vacuum bin, and the vacuum pump is communicated with the vacuum bin;
the calibration structure further comprises a vacuum supplement pumping device, a vacuum stabilizing unit and a vacuum back-lifting device which are sequentially connected in series;
the vacuum compensation pumping device, the vacuum stabilizing unit and the vacuum back-lifting device are connected in series and then are connected in parallel with a pipeline communicated with the vacuum pump and the vacuum bin;
the vacuum pump is connected with a vacuum pump motor;
the vacuum pump and the vacuum pump motor are both arranged on the movable frame;
a fan is arranged on the movable frame;
and the vacuum pump motor, the vacuum compensation pumping device, the vacuum return lifting device, the vacuum stabilizing unit and the fan are all connected with the PLC.
2. The vacuum gauge dynamic calibration apparatus of claim 1, wherein: an exhaust capillary tube used for controlling the pressure difference of the vacuum calibration pump is arranged in the vacuum stabilization unit, a first electromagnetic valve used for controlling the on-off of the exhaust capillary tube and the vacuum pumping device is installed at one end of the exhaust capillary tube, a second electromagnetic valve used for controlling the on-off of the exhaust capillary tube and the atmosphere is installed at the other end of the exhaust capillary tube, and the exhaust capillary tube is normally connected with the vacuum pumping device.
3. The vacuum gauge dynamic calibration apparatus of claim 2, wherein: the exhaust capillary tube is provided with one or more than one.
4. The vacuum gauge dynamic calibration apparatus of claim 1, wherein: the vacuum bin is provided with a first vacuum bent joint and a second vacuum bent joint, the first vacuum bent joint is connected with a standard vacuum sensor for detecting the vacuum degree value in the vacuum bin, and the second vacuum bent joint is connected with a calibrated vacuum sensor;
and the standard vacuum sensor is connected with the PLC.
5. The vacuum gauge dynamic calibration apparatus of claim 4, wherein: a special vacuum valve is mounted on the first vacuum elbow joint, and the standard vacuum sensor is communicated with the vacuum bin through the special vacuum valve;
the special vacuum valve is connected with the PLC.
6. The vacuum gauge dynamic calibration apparatus of claim 4, wherein: a vacuum calibration valve is arranged on the second vacuum elbow, and the calibrated vacuum gauge is communicated with the vacuum bin through the vacuum calibration valve;
the vacuum calibration valve is connected with the PLC.
7. The vacuum gauge dynamic calibration apparatus of claim 1, wherein: the PLC is internally provided with an analog input/output module, the analog input/output module is provided with ports suitable for different output signals, and the ports are used for inputting/outputting current, voltage and frequency signals;
the port is connected to a vacuum sensor to be tested.
8. The vacuum gauge dynamic calibration apparatus of claim 1, wherein: the output end of the vacuum pump is connected with a first two-way electromagnetic valve, and a second two-way electromagnetic valve is arranged on a pipeline between the first two-way electromagnetic valve and the vacuum bin;
and the vacuum compensation pumping device, the vacuum stabilizing unit and the vacuum back-lifting device are connected in series and then are connected with the two-way electromagnetic valve II in parallel.
9. The vacuum gauge dynamic calibration apparatus of claim 6, wherein: the second vacuum elbow is provided with one or more, and correspondingly, the vacuum calibration valve is provided with one or more.
10. The vacuum gauge dynamic calibration apparatus of claim 1, wherein: and a vacuum pump handle is arranged on the vacuum pump.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922006172.0U CN211291867U (en) | 2019-11-19 | 2019-11-19 | Dynamic calibration device for vacuum gauge |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922006172.0U CN211291867U (en) | 2019-11-19 | 2019-11-19 | Dynamic calibration device for vacuum gauge |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN211291867U true CN211291867U (en) | 2020-08-18 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201922006172.0U Active CN211291867U (en) | 2019-11-19 | 2019-11-19 | Dynamic calibration device for vacuum gauge |
Country Status (1)
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|---|---|
| CN (1) | CN211291867U (en) |
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2019
- 2019-11-19 CN CN201922006172.0U patent/CN211291867U/en active Active
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Address after: 266000 second floor, building 4, No.19 Hechuan Road, Licang District, Qingdao City, Shandong Province Patentee after: Shandong aoshengtai Testing Technology Co.,Ltd. Address before: 266000 second floor, building 4, No.19 Hechuan Road, Licang District, Qingdao City, Shandong Province Patentee before: SHANDONG ZHONGJIANGAOKE TESTING TECHNOLOGY Co.,Ltd. |
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Effective date of registration: 20230412 Address after: 266000 Building G, Industrial Park Road South, both sides of Yingjiu Road, Jiaodong Street Office, Jiaozhou City, Qingdao City, Shandong Province Patentee after: Aiyouxin (Shandong) Measurement and Testing Co.,Ltd. Address before: 266000 second floor, building 4, No.19 Hechuan Road, Licang District, Qingdao City, Shandong Province Patentee before: Shandong aoshengtai Testing Technology Co.,Ltd. |