A capacitance diaphragm gauge calibration device

Abstract

The application discloses a kind of capacitive thin film vacuum gauge tuning measuring devices, can complete the debugging work of batch before vacuum gauge completes packaging, and efficiency is high, cost controllable.The device, main vacuum chamber pumping assembly is connected main vacuum chamber by first pumping connection pipeline, for maintaining the pressure of main vacuum chamber at background state;Test chamber pumping assembly is connected each test chamber by second pumping connection pipeline, for maintaining the pressure of test chamber at background state;Gas distribution assembly is connected each test chamber by gas supply pipeline, for supplying gas to test chamber;Test chamber is divided into different groups according to the range of measured vacuum gauge, and the pressure sensor of corresponding range is connected;Each test chamber provides more than one vacuum gauge connection end;The reference cavity of each measured vacuum gauge is connected bellows by first connecting piece, and the bellows corresponding to all measured vacuum gauges are connected into the main vacuum chamber;The measuring cavity of measured vacuum gauge is connected the test chamber of corresponding range by second connecting piece.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of vacuum measuring instruments and its metrological testing, and particularly relates to a kind of capacitive diaphragm vacuum gauge adjustment device. BACKGROUND

[0002] Capacitive diaphragm vacuum gauge is a kind of rough low vacuum measuring instrument. Generally, the vacuum gauge contains a measuring cavity and a reference cavity, and the measuring cavity is separated from the reference cavity by an elastic diaphragm. The reference cavity is generally in a high vacuum state, and its pressure is much lower than that of the measuring end. The vacuum environment is usually maintained by a getter. When the vacuum environment of the measuring cavity changes, the diaphragm deforms elastically, causing a change in the capacitance between the diaphragm and the fixed electrode, and thus realizing the measurement of the vacuum degree. Capacitive diaphragm vacuum gauge has many advantages such as high measurement accuracy, good linearity, good repeatability and long-term stability of output, ability to measure total pressure of gas and vapor, and independence of measurement results from gas composition and type, and is widely used in the fields of vacuum measurement, microelectronics industry, surface treatment, plasma measurement, aerospace, high-energy physics, controlled thermonuclear fusion, etc.

[0003] The flatness of the diaphragm welding, the tension of the diaphragm and the distance between the plate and the diaphragm determine the electrical properties of the vacuum gauge. In general, after the sensor is processed, the electrical properties of the vacuum gauge need to be debugged. For vacuum gauges that meet the specifications, the circuit can be matched, while unqualified sensors will be scrapped. The scrapping of sensors to some extent causes waste of materials and increases the production cost of the vacuum gauge. The electrical performance of the capacitive diaphragm vacuum gauge can be completed before the reference cavity is packaged. Pre-adjustment of the vacuum gauge not only saves material cost, but also allows fine adjustment of the electrode position to meet the requirements when the initial capacitance between the fixed electrode and the elastic diaphragm of the vacuum gauge does not meet the requirements. Pre-adjustment of the capacitive diaphragm vacuum gauge is of great significance to the improvement of its productivity.

[0004] The existing adjustment device needs to put the vacuum gauge into a large vacuum tank, so it can only adjust a small number of vacuum gauges, and the efficiency is low when debugging in batches and on a large scale, causing waste of time, manpower and material resources. If multiple vacuum tanks or large-volume vacuum tanks are used, the cost will increase. SUMMARY

[0005] To solve the above problems, the present application aims to provide a device that can debug capacitive diaphragm vacuum gauges in batches, and can complete the batch debugging work before the vacuum gauge is packaged, with high debugging efficiency and controllable cost.

[0006] To achieve the above purpose, the main technical solutions adopted by the present application include:

[0007] The device comprises a main vacuum chamber evacuation assembly, a test chamber evacuation assembly, a main vacuum chamber, multiple test chambers, a gas distribution assembly and a data acquisition system.

[0008] The main vacuum chamber evacuation assembly is connected to the main vacuum chamber through a first evacuation connecting pipeline, and is used to maintain the pressure of the main vacuum chamber at a background state.

[0009] The test chamber evacuation assembly is connected to each test chamber through a second evacuation connecting pipeline, and is used to maintain the pressure of the test chamber at a background state.

[0010] The gas distribution assembly is connected to each test chamber through a gas supply pipeline, and is used to supply gas to the test chamber.

[0011] The test chambers are divided into different groups according to the range of the measured vacuum gauge, and are connected to pressure sensors corresponding to the range; each test chamber provides one or more vacuum gauge connection ends.

[0012] The reference cavity of each measured vacuum gauge is connected to a bellows through a first connecting piece, and the bellows corresponding to all measured vacuum gauges are connected to the main vacuum chamber; the measurement cavity of the measured vacuum gauge is connected to the test chamber of the corresponding range through a second connecting piece.

[0013] The data acquisition system is connected to the main vacuum chamber evacuation assembly, the test chamber evacuation assembly, and various sensors and valves on the pipelines; during calibration and measurement, the main vacuum chamber evacuation assembly and the test chamber evacuation assembly are opened, and the pressures of the main vacuum chamber and the test chamber are evacuated to the background state; then the evacuation pipeline is cut off, the gas distribution assembly is opened to supply gas to each test chamber, the pressure of the test chamber is increased according to the range of the vacuum gauge, and the signal output of the measurement cavity of the vacuum gauge connected to the test chamber is monitored.

[0014] Preferably, one side of the first connecting piece is a standard flange, and the other side is a reference cavity connecting flange matched with the reference cavity of the measured vacuum gauge; the standard flange is used to connect the bellows; the reference cavity connecting flange is connected to the reference cavity of the measured vacuum gauge, and is tightly sealed through a sealing part at the connecting surface; an electrical interface is provided at the reference cavity connecting flange, which communicates the reference cavity with the external environment, and is used to output electrical signals.

[0015] Preferably, the main vacuum chamber is provided with a vacuum gauge for detecting the pressure of the main vacuum chamber.

[0016] Preferably, the test chamber is further connected to a buffer tank, and the pressure of the test chamber is controlled to increase at a specified rate by adjusting the volume of the buffer tank.

[0017] Preferably, an adjusting valve is provided in the gas distribution assembly, which is used to control the pressure of the test chamber to increase at a specified rate.

[0018] Preferably, the test chamber pressure rise rate is set according to the vacuum gauge range, and a small range corresponds to a slow rate, so that the pressure rise within the range is completed within a set time.

[0019] Preferably, the pressure sensor is selected from a capacitive diaphragm gauge or a pressure transmitter.

[0020] Preferably, the data acquisition system controls the configuration system to stop supplying air to the test chamber when all the measured vacuum gauges connected to the test chamber give a signal or exceed the debugging range.

[0021] Preferably, in the main vacuum chamber evacuation assembly, the first mechanical pump is connected to the first valve V4 and then divided into two branches, the first branch is connected to the second valve V2, the molecular pump, the third valve V1 in turn, and then connected to the main vacuum chamber, and the outlet of the third valve V1 in the first branch is provided with a compound gauge G1; the fourth valve V3 is connected in series on the second branch and then connected to the main vacuum chamber.

[0022] Preferably, the test chamber is connected to two pressure sensors with different ranges, so that one test chamber can measure vacuum gauges of two ranges.

[0023] Compared with the existing conventional device, the beneficial effects of the present application are as follows:

[0024] (1) The conventional vacuum gauge is tested after packaging, and once the performance index of the vacuum gauge does not meet the requirements, the vacuum gauge will be scrapped, which not only increases the manufacturing cost of the vacuum gauge, but also the existing capacitive diaphragm vacuum gauge testing device can only test a small number of vacuum gauges, and is relatively bulky, not suitable for mass production of vacuum gauges. The present application changes the sealing method of the traditional testing device through external equipment, and through the design of the split structure of the main vacuum chamber + test chamber, dozens of vacuum gauges can be connected for debugging at the same time, which greatly reduces the testing difficulty and improves the vacuum gauge debugging efficiency and saves the debugging cost.

[0025] (2) The present application can adapt to vacuum gauges of various ranges by grouping the ranges, and can test multiple vacuum gauges at the same time, without the need to design different testing devices for different vacuum gauges, thereby reducing the automatic testing cost.

[0026] (3) The present application uses a data acquisition system to automatically collect, realizes batch automatic testing of capacitive diaphragm vacuum gauges.

[0027] (4) The present application improves the efficiency of vacuum gauge testing and saves manpower and material resources. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The present application is a capacitive diaphragm vacuum gauge testing device schematic diagram.

[0029] Figure 2 This is a structural diagram of the capacitor thin-film vacuum gauge adjustment device in a preferred embodiment of the present invention.

[0030] Figure 3 This is a structural diagram of the first connector of the present invention.

[0031] In the diagram: R1, R2, R3, R4 - Test chamber; R5 - Main vacuum chamber; R6 - Stabilizing chamber; R11, R21 - Buffer tank; TMP1 - Molecular pump; DP1, DP2 - Mechanical pump; G1 - Compatibility gauge; G11, G12, G21, G22, G31, G32 - Capacitive diaphragm gauge; G2 - Pressure transmitter; G41 - Pressure transmitter; V1~V5, V11~V19, V21~V29, V31~V38, V41~V47 - Valves; F1 - Gas source; Z1 - Reference chamber; Z2 - Measuring chamber; 1 - Standard flange; 2 - Reference chamber connection flange; 3 - Sealing component; 4 - Electrical interface. Detailed Implementation

[0032] This invention provides a device for adjusting a capacitive thin-film vacuum gauge, such as... Figure 1 As shown, the device includes a main vacuum chamber pumping assembly, a test chamber pumping assembly, a main vacuum chamber, multiple test chambers, a gas distribution assembly, and a data acquisition system.

[0033] The main vacuum chamber pumping assembly, test chamber pumping assembly, and gas distribution assembly provide suitable pressure for the vacuum gauge system. Specifically, the main vacuum chamber pumping assembly is connected to the main vacuum chamber via a first pumping connection pipe to maintain the main vacuum chamber pressure at a background level; the test chamber pumping assembly is connected to each test chamber via a second pumping connection pipe to maintain the test chamber pressure at a background level. The gas distribution assembly is connected to each test chamber via a gas supply pipe to supply gas to the test chambers.

[0034] The test chambers are divided into different groups according to the range of the vacuum gauge being tested, and pressure sensors of the corresponding range are connected; each test chamber provides more than one vacuum gauge connection terminal.

[0035] The reference chamber of each vacuum gauge under test is connected to a bellows via a specially designed connector, and the bellows corresponding to all vacuum gauges under test are connected to the main vacuum chamber; the measuring chamber of the vacuum gauge under test is connected to the test chamber of the corresponding range via a flange.

[0036] The data acquisition system can realize automatic acquisition of parameters. The data acquisition system is connected with a main vacuum chamber pumping assembly, a test chamber pumping assembly and various sensors and valves on the pipeline; during adjustment and testing, the main vacuum chamber pumping assembly and the test chamber pumping assembly are opened, and the pressure of the main vacuum chamber and the test chamber is pumped to the background state; then the pumping pipeline is cut off, the gas distribution assembly is opened to supply gas to each test chamber, the pressure of the test chamber is increased according to the range of the vacuum gauge, and the signal output of the test chamber connected to the vacuum gauge measuring cavity is monitored. The device can complete the debugging of the uncompleted packaged capacitive diaphragm vacuum gauge and the differential pressure capacitive diaphragm vacuum gauge, and batch realizes the pre-detection and debugging of the capacitive diaphragm vacuum gauge.

[0037] It can be seen that, by designing the split structure of the main vacuum chamber + test chamber and grouping the range, the device can realize sealing by using the vacuum gauge itself in cooperation with the flange without the need for a vacuum tank; the device can simultaneously connect vacuum gauges of multiple ranges, complete the debugging of uncompleted packaged capacitive diaphragm vacuum gauges and differential pressure capacitive diaphragm vacuum gauges, and batch realize automatic pre-detection and debugging of multiple models of vacuum gauges. The present application improves the efficiency of vacuum gauge adjustment and testing, and saves manpower and material resources.

[0038] Figure 2 The structure diagram of the capacitive diaphragm vacuum gauge adjustment and testing device of the preferred embodiment of the present application is shown. As shown in the figure, Figure 1 The device shows an example of one main vacuum chamber (R5) + four test chambers (R1-R4). One of the four test chambers, R4, is designed for high-pressure products.

[0039] In this embodiment, the main vacuum chamber pumping assembly includes: a mechanical pump DP1 connected with a valve V4 and divided into two branches, a first branch connected with a valve V2, a molecular pump TMP1, a valve V1 in sequence and then connected with the main vacuum chamber, and the outlet of the valve V1 in the first branch is provided with a compound gauge G1; a second branch connected with a valve V3 in sequence and then connected with the main vacuum chamber. In use, the valve V4 and the valve V3 are opened first, and the second branch is used for rough pumping, when the pressure is reduced to the order of tens of Pa, the first branch is opened, the molecular pump TMP1 is added to work, and the pumping is performed to the background pressure, which is generally 10 -1 Pa order.

[0040] The test chamber pumping assembly includes: a mechanical pump DP2 connected with each test chamber through a connecting pipeline, and the connecting pipeline is provided with valves (V16, V26, V36, V46).

[0041] The gas distribution assembly includes: the gas source F1 is connected to the pressure stabilizing chamber R6 through the valve V5, and then is connected to each test chamber through the connecting pipeline. The pressure stabilizing chamber R6 is connected to the pressure transmitter G2. Each test chamber is provided with a valve group on the connecting pipeline. In the embodiment, each valve group includes three valves, for example, an on-off valve, a manual flow regulating valve and an electronic flow regulating valve. The three-valve combination can realize flow regulation, so as to control the test chamber pressure to rise at a specified rate, and can also ensure the safety of pipeline opening and closing control. For example, the gas supply pipeline of the test chamber R1 is provided with the valves V13-V15.

[0042] The main vacuum chamber R5 is connected to the reference cavity of the vacuum gauge to be tested, and is used for maintaining the reference cavity of the capacitive diaphragm vacuum gauge at a lower vacuum pressure. The whole system shares one main vacuum chamber R5. Preferably, the main vacuum chamber can be provided with a vacuum gauge (not shown in the figure) for detecting the pressure of the main vacuum chamber.

[0043] The test chamber is used for providing pressure to the measurement cavity of the vacuum gauge, and measuring the effective range of the vacuum gauge. In the embodiment, five test chambers R1-R4 are included, which are divided into two groups according to the range of the vacuum gauge to be tested. R1-R3 are one group, and R4 is one group. Each test chamber in R1-R3 is connected to two pressure sensors, and the two pressure sensors are of different ranges, for example, one is a range below 1000 Pa, and the other is a range below 100,000 Pa. The pressure sensor can be a capacitive diaphragm gauge. For example, the test chamber R1 is connected to two capacitive diaphragm gauges G11 and G12. Each capacitive diaphragm gauge is connected to the test chamber through a valve. The test chamber R4 is for high-pressure products, and is connected to the pressure transmitter G41.

[0044] Each test chamber provides one or more vacuum gauge connection ends. In the embodiment, each test chamber provides five vacuum gauge connection ends. The test chamber is also connected to a buffer tank, and the test chamber pressure is controlled to rise at a specified rate by adjusting the volume of the buffer tank. For example, the test chamber R1 is connected to the buffer tank R11, and the buffer tank is connected to the test chamber through the valve V19, so that whether the buffer tank is used or not can be controlled.

[0045] For each vacuum gauge, the reference cavity Z1 is connected to the bellows through a first connecting piece, and then is connected to the main vacuum chamber R5 to realize sealing. For example, the reference cavity Z1 of the vacuum gauge G1 is connected to the bellows through the first connecting piece G1a, and then is connected to the main vacuum chamber R5 through the second connecting piece G1b. Figure 3As shown, one side of the first connecting piece is a standard flange 1, and the other side is a reference cavity connecting flange 2 specially designed to match the reference cavity; the standard flange 1 is used to connect the bellows; the reference cavity connecting flange 3 is connected to the reference cavity Z1 of the measured vacuum gauge, and is tightly sealed through the sealing component 3 at the connecting surface; the sealing component 3 is arranged in the sealing groove opened in the inner wall of the reference cavity connecting flange 2. The sealing groove can be opened in the circular bottom surface of the reference cavity connecting flange 2 (as shown), or can be arranged on the annular inner side surface. An electrical interface 4 is arranged at the bottom surface of the reference cavity connecting flange 2, which communicates the reference cavity with the external environment and is used to guide out the electrical signal; preferably, the standard flange 1 is connected by a KF16 flange; the sealing component 3 is a rubber sealing ring. All the bellows of the measured vacuum gauges are connected to the main vacuum chamber, and one main vacuum chamber provides the background pressure for all the reference cavities. The measuring cavity Z2 of the measured vacuum gauge is connected to the test chamber of the corresponding range through the second connecting piece. The second connecting piece can adopt the flange of the vacuum gauge itself.

[0046] The data acquisition system is connected to the main vacuum chamber pumping assembly, the test chamber pumping assembly, and various sensors and valves on the pipeline; the adjustment and measurement process is as follows:

[0047] Step a: connect the reference cavity of the vacuum gauge to be adjusted and measured to the main vacuum chamber, connect the measuring cavity to a certain test chamber, and connect the measurement signal output to the data acquisition system. Here, the vacuum gauge to be adjusted and measured is connected to the test chamber R1 as an example.

[0048] Step b: open the main vacuum chamber pumping assembly and the test chamber pumping assembly, and pump the pressure of the main vacuum chamber and the test chamber to the background state.

[0049] Step c: close the test chamber pumping valve, thereby cutting off the pumping pipeline. Open the gas distribution assembly to supply gas to each test chamber, and increase the pressure of the test chamber according to the range of the vacuum gauge. For example, close the pumping valve V16, and open the inlet valves V13, V14 and V15 of the test chamber R1.

[0050] In this step, the pressure of the test chamber is increased at a rate corresponding to the range of the vacuum gauge by adjusting the inlet valves and the volume of the buffer tank. The pressure increase rate of the test chamber is set according to the range of the vacuum gauge, i.e. a slow rate for a small range and a fast rate for a large range, so that the pressure increase within the range is completed within a set time, thereby controlling the measurement error.

[0051] Step d: the data acquisition system monitors the signal output of the measuring cavity of the vacuum gauge connected to the test chamber. When the sensor of the vacuum gauge reaches the upper limit of the range, the output is sent to the data acquisition system, and the information of the test vacuum gauge is recorded. When all the vacuum gauges give signals or exceed the debugging range, stop the gas inlet.

[0052] Step e: close all the valves, remove the vacuum gauge, and record the adjustment and measurement data.

[0053] The above specific embodiments only describe the design principles of the present application, and the shapes and names of the components in the description can be different and are not limited. Therefore, those skilled in the art of the present application can modify or equivalently replace the technical solutions described in the foregoing embodiments; and these modifications and replacements do not deviate from the purpose and technical solutions of the present application, and should all belong to the protection scope of the present application.

Claims

1. A device for adjusting a capacitive thin-film vacuum gauge, characterized in that, include: The system includes a main vacuum chamber pumping assembly, a test chamber pumping assembly, one main vacuum chamber, multiple test chambers, a gas distribution assembly, and a data acquisition system. The main vacuum chamber pumping assembly is connected to the main vacuum chamber through the first pumping connection pipe, and is used to maintain the pressure of the main vacuum chamber at the background level. The test chamber extraction assembly is connected to each test chamber through a second extraction connection pipe to maintain the test chamber pressure at the background level. The gas distribution assembly is connected to each test chamber via gas supply pipelines and is used to supply gas to the test chambers; The test chambers are divided into different groups according to the range of the vacuum gauge being tested, and pressure sensors of the corresponding range are connected; each test chamber provides more than one vacuum gauge connection terminal; The reference chamber of each vacuum gauge under test is connected to a bellows via a first connector, and the bellows corresponding to all vacuum gauges under test are connected to the main vacuum chamber; the measuring chamber of the vacuum gauge under test is connected to the test chamber of the corresponding range via a second connector. The data acquisition system connects the main vacuum chamber pumping assembly, the test chamber pumping assembly, and various sensors and valves on the pipelines. During testing, the main vacuum chamber pumping assembly and the test chamber pumping assembly are opened to pump the pressure in the main vacuum chamber and the test chamber to the background state. Then, the pumping pipeline is cut off, and the gas distribution assembly is turned on to supply gas to each test chamber, increasing the pressure in the test chamber according to the vacuum measurement range. The pressure increase rate in the test chamber is set according to the vacuum measurement range, with a slow rate for a smaller range and a fast rate for a larger range, so that the pressure increase within the range is completed within the set time. The system monitors the signal output of the vacuum gauge measuring chamber connected to the test chamber. When the tested vacuum gauge reaches the upper limit of its range, it outputs to the data acquisition system, and the test vacuum gauge information is recorded. When all vacuum gauges give signals or exceed the debugging range, the gas intake is stopped. One side of the first connector is a standard flange, and the other side is a reference cavity connection flange that matches the reference cavity of the vacuum gauge under test. The standard flange is used to connect the bellows. The reference cavity connection flange is connected to the reference cavity of the vacuum gauge under test and is fastened and sealed by the sealing component at the connection surface. An electrical interface is provided at the reference cavity connection flange to connect the reference cavity with the external environment and to export electrical signals.

2. The capacitor film vacuum gauge adjustment device according to claim 1, characterized in that, The main vacuum chamber is equipped with a vacuum gauge to detect the pressure in the main vacuum chamber.

3. The capacitor film vacuum gauge adjustment device according to claim 1, characterized in that, The test chamber is further connected to a buffer tank, and by adjusting the volume of the buffer tank, the pressure in the test chamber is controlled to increase at a specified rate.

4. The capacitor film vacuum gauge adjustment device according to claim 1, characterized in that, A regulating valve is installed in the gas distribution assembly to control the pressure in the test chamber to increase at a specified rate.

5. The capacitor film vacuum gauge adjustment device according to claim 1, characterized in that, The pressure sensor is either a capacitive diaphragm gauge or a pressure transmitter.

6. The capacitor film vacuum gauge adjustment device according to claim 1, characterized in that, In the main vacuum chamber pumping assembly, the first mechanical pump is connected to the first valve V4 and then splits into two branches. The first branch is connected in sequence to the second valve V2, the molecular pump, and the third valve V1 and then connected to the main vacuum chamber. The outlet of the third valve V1 in the first branch is equipped with a recombination device G1. The second branch is connected in series with the fourth valve V3 and then connected to the main vacuum chamber.

7. The capacitor film vacuum gauge adjustment device according to claim 1, characterized in that, The test chamber is connected to two pressure sensors with different ranges, allowing one test chamber to perform vacuum gauge measurements for two different ranges.

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