Temperature control system of film vacuum gauge

Abstract

The invention provides a temperature control system of a film vacuum gauge, which relates to the technical field of vacuum air pressure measuring equipment and comprises a heater, a sensor and a temperature controller. Wherein the heater is of a cylindrical barrel structure, and a film vacuum gauge is placed in the heater; the temperature controller controls the heater to uniformly heat the film vacuum gauge in a constant current mode based on a preset temperature; the sensor is arranged in the heater and used for detecting the real-time temperature in the heater and feeding back the real-time temperature to the temperature controller so that the temperature controller can adjust heating parameters of the heater. The temperature control system provided by the invention is a closed-loop control system, based on the control of the temperature controller, the system is always kept in a constant current mode for heating, the current and voltage fluctuation is small, the temperature is always kept constant, and for a capacitive film vacuum gauge with a small size, stable acquisition of capacitance can be realized, and the measurement accuracy is improved. The detection precision of the film vacuum gauge is ensured, and the application range is wide.

Description

Technical Field

[0001] The invention relates to the technical field of vacuum pressure measuring equipment, and in particular to a temperature control system of a thin film vacuum gauge. Background Art

[0002] As a high-precision, high-sensitivity and high-stability measuring instrument, the measurement accuracy of the capacitive thin film vacuum gauge is easily affected by the ambient temperature. However, in the face of complex operating environments, temperature changes are usually difficult to control, or it costs a lot to maintain a constant temperature.

[0003] Existing constant temperature heating systems usually use relays to control the on and off of thermocouples, and then cooperate with sensors to achieve constant temperature by temperature feedback. Such constant temperature heating systems have large current fluctuations and low temperature control accuracy, and are generally only used for temperature control of larger capacitive thin film vacuum gauges. However, when the volume of the capacitive thin film vacuum gauge is small, the capacitance change is small when measuring air pressure, and several dozen times of voltage amplification is required to achieve effective information collection. When using traditional constant temperature heating systems for heating, the current and voltage fluctuations are large, which will affect the stability of capacitance collection, thereby affecting the detection accuracy of the thin film vacuum gauge. Summary of the invention

[0004] In view of the shortcomings of the above-mentioned prior art, the present invention provides a temperature control system for a thin film vacuum gauge, which solves the technical problems of large current and voltage fluctuations and low temperature control accuracy of the constant temperature heating system used in the prior art, which affects the detection accuracy of the thin film vacuum gauge.

[0005] The present invention provides a temperature control system for a thin film vacuum gauge, comprising a heater, a sensor and a temperature controller;

[0006] The heater is a cylindrical barrel structure, a control circuit board is arranged in the side wall of the heater, and a thin film vacuum gauge is placed in the heater;

[0007] The temperature controller is electrically connected to the control circuit board, and the temperature controller controls the heater to uniformly heat the thin film vacuum gauge in a constant current mode based on a preset temperature;

[0008] The sensor is arranged in the heater, the sensor is electrically connected to the control circuit board, and the sensor is used to detect the real-time temperature inside the heater and feed back the real-time temperature to the temperature controller so that the temperature controller adjusts the heating parameters of the heater.

[0009] Optionally, the temperature control system of the thin film vacuum gauge further includes a safety device;

[0010] The safety device is arranged on the outer wall of the heater and is electrically connected to the control circuit board.

[0011] Optionally, a fuse is provided in the safety device, and the fuse is electrically connected to the control circuit board;

[0012] When the sensor detects that the real-time temperature inside the heater is higher than a temperature threshold, the fuse blows.

[0013] Optionally, a PID control system is provided in the temperature controller;

[0014] The PID control system is used to calculate the temperature difference between the preset temperature and the real-time temperature, so that the temperature controller adjusts the output power of the heater based on the temperature difference to control the heater to uniformly heat the thin film vacuum gauge based on the preset temperature in a constant current mode.

[0015] Optionally, the control circuit board is connected to a wiring device, the wiring device is arranged on an upper edge of the side wall of the heater, and the temperature controller is electrically connected to the control circuit board through the wiring device.

[0016] Optionally, a connection hole is formed at the bottom of the inner wall of the heater, and the sensor is arranged on the bottom surface inside the heater and is electrically connected to the control circuit board through the connection hole.

[0017] Optionally, the sensor is prepared based on a thermocouple or a thermal resistor.

[0018] Optionally, the sensor is used to detect the real-time temperature inside the heater, and dynamically adjust the real-time temperature inside the heater based on a compensation algorithm, so as to transmit the adjusted real-time temperature to the temperature controller through the control circuit board.

[0019] Optionally, the heater is made of flexible heating material.

[0020] Optionally, the film and the supporting structure of the thin film vacuum gauge are both made of materials with low thermal expansion coefficient.

[0021] The temperature control system of the thin film vacuum gauge provided by the present invention has a heater with a cylindrical barrel structure, which can ensure that the thin film vacuum gauge is heated evenly and avoid measurement errors caused by local overheating or uneven heating; the temperature controller can accurately control the heating power of the heater, thereby realizing accurate control of the working environment temperature of the thin film vacuum gauge; the sensor monitors the internal temperature of the heater in real time, and feeds back the internal temperature data to the temperature controller, forming a closed-loop control system, which can adjust the heating parameters in time to maintain the set temperature value. The temperature control system provided by the present application is a closed-loop control system, which is based on the control of the temperature controller, so that the system always maintains heating in a constant current mode, with small current and voltage fluctuations, and the temperature always remains constant. For a small-volume capacitive thin film vacuum gauge, it can also realize stable capacitance acquisition, ensuring the detection accuracy of the thin film vacuum gauge, and has a relatively wide range of applications.

[0022] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0023] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0025] Figure 1 A structural diagram of a temperature control system of a thin film vacuum gauge in an embodiment provided in the present application;

[0026] Figure 2 A schematic diagram of the connection relationship of a temperature control system of a thin film vacuum gauge in an embodiment provided in the present application.

[0027] In the figure:

[0028] 1. Heater; 2. Sensor; 3. Safety device; 4. Wiring device. DETAILED DESCRIPTION

[0029] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0031] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] The present invention provides a temperature control system for a thin film vacuum gauge, such as Figure 1 and Figure 2 As shown, it includes a heater 1, a sensor 2 and a temperature controller; wherein the heater 1 is a cylindrical barrel structure, a control circuit board is arranged inside the side wall of the heater 1, and a thin film vacuum gauge is placed inside the heater 1; the temperature controller is electrically connected to the control circuit board, and the temperature controller controls the heater 1 to uniformly heat the thin film vacuum gauge in a constant current mode based on a preset temperature; the sensor 2 is arranged in the heater 1, and the sensor 2 is electrically connected to the control circuit board, and the sensor 2 is used to detect the real-time temperature inside the heater 1, and feed back the real-time temperature to the temperature controller, so that the temperature controller adjusts the heating parameters of the heater 1.

[0033] The temperature control system of the thin film vacuum gauge provided by the present application, the heater 1 adopts a cylindrical barrel structure, which can ensure that the thin film vacuum gauge is evenly heated, avoiding local overheating or uneven heating and causing measurement errors; the temperature controller can accurately control the heating power of the heater 1, thereby realizing accurate control of the working environment temperature of the thin film vacuum gauge; the sensor 2 monitors the internal temperature of the heater 1 in real time, and feeds back the internal temperature data to the temperature controller, forming a closed-loop control system, which can adjust the heating parameters in time to maintain the set temperature value. The temperature control system provided by the present application is a closed-loop control system, which is based on the control of the temperature controller, so that the system always maintains heating in the constant current mode, the current and voltage fluctuations are small, and the temperature is always kept constant. For the smaller capacitive thin film vacuum gauge, it can also realize the stable acquisition of capacitance, ensure the detection accuracy of the thin film vacuum gauge, and has a relatively wide range of applications.

[0034] Among them, the constant current mode is a current control method, that is, the current is maintained at a constant level and is not affected by voltage changes; in the present application, the constant current mode is to ensure that the heating power of the heater 1 is stable, thereby achieving precise control of the temperature. Specifically, the temperature controller receives the temperature signal from the sensor 2 and calculates the required heating current according to the preset temperature target. The heater 1 is a resistive load, which generates heat when current passes through it. In the constant current mode, the current in the heater 1 remains unchanged, which means that the heating power is also relatively stable, so that uniform heating of the thin film vacuum gauge can be achieved. The sensor 2 continuously detects the temperature in the heater 1 and feeds back the information to the temperature controller, so that the temperature controller will adjust the current in the heater 1 accordingly to maintain the temperature stability. Therefore, the present application always maintains the constant current mode for heating, ensuring that the heating power of the heater 1 is stable and predictable, thereby achieving effective control of the temperature of the thin film vacuum gauge.

[0035] Specifically, in the above embodiment, if Figure 1 As shown, the temperature control system of the thin film vacuum gauge further includes a safety device 3; the safety device 3 is attached to the outer wall of the heater 1, and the safety device 3 is electrically connected to the control circuit board.

[0036] In this embodiment, the safety device 3 can cut off the circuit when the heater 1 overheats or under other abnormal circumstances, thereby preventing safety accidents caused by temperature runaway, such as fire or equipment damage. Specifically, when the heater 1 is overloaded for some reason, such as due to a short circuit, the safety device 3 can disconnect the circuit in time to protect the heater 1 and other components from damage. The setting of the safety device 3 ensures that the system will not fail due to accidental overheating, helps to maintain the long-term stable operation of the system, and improves the reliability and safety of the overall system.

[0037] Furthermore, a fuse is provided in the safety device 3 , and the fuse is electrically connected to the control circuit board; when the sensor 2 detects that the real-time temperature inside the heater 1 is higher than the temperature threshold, the fuse blows.

[0038] In this embodiment, the fuse is used as a simple and effective over-temperature protection measure, which can respond immediately without human intervention to ensure the safety of the system. In addition, the fuse is low-cost and is usually designed for single use. Once it blows, it needs to be replaced to facilitate rapid recovery of system functions. The fuse is also a temperature-sensitive component. When the temperature exceeds a preset temperature threshold, it can automatically cut off the power supply to play a protective role. When the internal temperature of the heater 1 is too high, the fuse will automatically blow, cutting off the power supply to prevent the temperature from continuing to rise, thereby protecting the thin film vacuum gauge and other components from damage and reducing the cost of repairing and replacing components. The present application sets a fuse in the safety device 3, which not only ensures the normal working state of the thin film vacuum gauge, but also ensures the personal safety of the operator and the integrity of the equipment.

[0039] Specifically, in the above embodiment, a PID control system is provided in the temperature controller; the PID control system is used to calculate the temperature difference between the preset temperature and the real-time temperature, so that the temperature controller adjusts the output power of the heater 1 based on the temperature difference, so as to control the heater 1 to uniformly heat the thin film vacuum gauge based on the preset temperature in the constant current mode.

[0040] Among them, the PID (Proportional-Integral-Derivative) control system specifically includes a proportional term (P), which adjusts the output power of the heater 1 according to the deviation, that is, the difference between the preset temperature and the real-time temperature. The larger the deviation, the larger the power adjustment range of the heater 1; the integral term (I), which takes into account the cumulative effect of the deviation over time, aims to eliminate static errors and make the system eventually stabilize at the preset temperature; the differential term (D), which adjusts the output power of the heater 1 according to the rate of change of the deviation, helps to suppress overshoot and speed up the response speed of the system; the control process of the PID control system is: the PID control system calculates the difference between the preset temperature and the real-time temperature, and then dynamically adjusts the output power of the heater 1 according to the calculated temperature difference, so that the heater 1 can be accurately heated to the preset temperature, and then the heater 1 works in a constant current mode. No matter how the load changes, the current remains unchanged, thereby ensuring the stability of the heating power.

[0041] In this embodiment, the PID control system can respond quickly to temperature changes and accurately adjust the output power of the heater 1, thereby achieving precise control of the working environment temperature of the thin film vacuum gauge; the existence of the differential term can respond quickly to temperature changes, reduce the time for the temperature to reach the preset value, and speed up the response speed of the system; the integral term can gradually eliminate static errors, ensure that the system eventually stabilizes near the preset temperature, and improve the accuracy of temperature control; the PID control system can also smoothly adjust the power of the heater 1, avoiding drastic temperature fluctuations, and helping to extend the service life of the thin film vacuum gauge and related components; the PID control system can also adapt well to the temperature control requirements under different environmental conditions, and maintain a high control accuracy even if the external conditions change; and the PID controller can automatically adjust the output power of the heater 1, making the temperature control system more intelligent and reducing the need for human intervention.

[0042] Specifically, in the above embodiment, Figure 1 and Figure 2 As shown, the control circuit board is connected to a wiring device 4 , which is arranged on the upper edge of the side wall of the heater 1 , and the temperature controller is electrically connected to the control circuit board through the wiring device 4 .

[0043] Among them, there are many forms of implementation of the wiring terminal, such as the wiring terminal, that is, a plurality of wiring holes or screws are provided on the wiring device 4, and the connection is completed by fastening the wires with screws; the plug and socket, which can achieve quick connection by inserting a plug with pins into the corresponding socket; the spring clamp type wiring terminal, which uses a spring-loaded clip to clamp the wire; the junction box, which contains components such as wiring terminals or plugs and sockets inside and has a cover or door on the outside; the terminal block; and the simplest way, the two wires of positive and negative poles can be connected, etc. The present application does not limit its specific implementation form.

[0044] In this embodiment, the wiring device 4 simplifies the connection between the temperature controller and the control circuit board, making installation and subsequent maintenance work more convenient; the wiring device 4 is set on the upper edge of the side wall of the heater 1, so that the staff can easily access the wiring device 4, which is convenient for inspection, debugging or replacement of components; connection through a dedicated wiring device 4 can ensure the safety and reliability of the electrical connection, and reduce safety hazards caused by poor contact or looseness; at the same time, the wiring device 4 allows the temperature controller to be flexibly connected with other components, which helps to upgrade or expand the system in the future, reduces customization requirements, reduces costs, and helps to reduce electromagnetic interference, ensuring that the signal transmission in the temperature control system is clearer and more accurate.

[0045] Specifically, in the above embodiment, a connection hole is formed at the bottom of the inner wall of the heater 1 , and the sensor 2 is arranged on the bottom surface inside the heater 1 and is electrically connected to the control circuit board through the connection hole.

[0046] In this embodiment, the sensor 2 is arranged on the bottom surface inside the heater 1, so that the temperature inside the heater 1 can be measured more accurately, ensuring that the temperature sensor 2 can directly reflect the ambient temperature of the thin film vacuum gauge; by setting a connecting hole at the bottom of the inner wall of the heater 1, the sensor 2 can be directly connected to the control circuit board through the connecting hole, which simplifies the wiring process, reduces the additional wiring complexity, and facilitates the installation and replacement of the sensor 2, and can also make the structure of the entire system more compact, save space, and facilitate the integration and layout of the system; the sensor 2 is in close contact with the heater 1, which can reduce the measurement error caused by improper position of the sensor 2 or poor wiring, and improve the reliability and accuracy of temperature control.

[0047] Specifically, in the above embodiments, the sensor 2 is prepared based on a thermocouple or a thermal resistor.

[0048] In this embodiment, thermocouples and thermal resistors are both commonly used temperature sensors 2, which can provide high-precision temperature measurement results and can also cover a wide temperature range, suitable for different working environments and application scenarios, ensuring that accurate measurement values ​​can be obtained under various temperature conditions; both types of sensors 2, thermocouples and thermal resistors, have good long-term stability, which can ensure the consistency and reliability of temperature measurement during long-term use, and both have a fast response time, can quickly respond to temperature changes, and help to achieve faster temperature control cycles. At the same time, they are also easy to integrate with temperature controllers and other electronic devices, simplifying the system design and installation process.

[0049] Specifically, in the above embodiment, the sensor 2 is used to detect the real-time temperature inside the heater 1, and dynamically adjust the real-time temperature inside the heater 1 based on the compensation algorithm, so as to transmit the adjusted real-time temperature to the temperature controller through the control circuit board.

[0050] Among them, the present application uses a compensation algorithm to correct the deviation of sensor 2, including factors such as zero drift and temperature coefficient, to ensure the accuracy of the measurement results. Considering that the output of sensor 2 is often not completely linear, the compensation algorithm can correct the nonlinear output to make the temperature measurement more accurate. The compensation algorithm can also consider the impact of environmental factors on temperature measurement and correct it. In summary, sensor 2 detects the real-time temperature inside the heater 1 in real time, and dynamically adjusts the output result through the compensation algorithm to reflect a more realistic temperature value.

[0051] In this embodiment, by correcting the output of sensor 2 through the compensation algorithm, the accuracy of temperature measurement can be significantly improved. More accurate temperature measurement results help to improve the stability of the temperature control system and reduce temperature fluctuations. The compensation algorithm can reduce false alarms caused by sensor 2 deviations or environmental factors, and improve the reliability and credibility of the system. The compensated temperature measurement value can better guide the temperature controller to adjust the output power of heater 1 to achieve more efficient temperature control. In addition, the compensation algorithm helps to improve the response speed of the system, so that the temperature control system can adapt to temperature changes more quickly.

[0052] Specifically, in the above embodiment, the material of the heater 1 is a flexible heating material.

[0053] Among them, considering the use function of the heater 1, the material of the heater 1 is selected from a flexible heating material whose resistance change rate is less affected by temperature. Specifically, a carbon fiber heating material can be selected. The carbon fiber heating material has good flexibility and a low temperature coefficient. Its resistance change rate is less affected by temperature. The carbon fiber heating material can generate heat evenly, has high heating efficiency, and maintains a stable resistance value within a wide temperature range. It is suitable for making a flexible heater 1. Metal foil heating materials, such as copper-nickel alloys, can also be selected. They have a low temperature coefficient and can maintain a stable resistance value within a wide temperature range. The metal foil heating material has good thermal conductivity and mechanical strength. , easy to process into various shapes, suitable for heaters that require flexible characteristics 1; PTC (positive temperature coefficient) thermistor materials can also be used, which have low resistance at low temperatures, and as the temperature rises, the resistance increases. This characteristic helps to automatically limit the heating power and prevent overheating, and can self-regulate the temperature to a certain extent, reducing dependence on external temperature controllers, and is suitable for occasions with high temperature control requirements; graphene heating materials can also be used, which have extremely high electrical conductivity and thermal conductivity, and a very low temperature coefficient, and are almost unaffected by temperature changes. Graphene heating materials are very light and thin, can be bent, and heat evenly, making them suitable for making high-performance flexible heaters 1.

[0054] In this embodiment, since the resistance change rate is less affected by temperature, the above materials can provide more stable heating performance, help improve the accuracy of temperature control, and usually have good thermal conductivity, which can achieve uniform distribution of temperature inside the heater 1; at the same time, the flexible heating material is easy to bend and cut, and the shape and size can be customized according to the specific needs of the thin film vacuum gauge, and the stable resistance change helps to reduce temperature fluctuations and improve the stability and reliability of the entire temperature control system. The selection of flexible heating materials enables the heater 1 to reach and maintain the preset temperature more efficiently, thereby reducing energy consumption.

[0055] Specifically, in the above embodiments, the thin film and the supporting structure of the thin film vacuum gauge are both made of materials with low thermal expansion coefficient.

[0056] In this embodiment, for the thin film vacuum gauge, using materials with low thermal expansion coefficient and good thermal stability to manufacture the film and support structure can help reduce deformation caused by temperature changes, thereby improving temperature stability. The following materials can usually be used: quartz glass (SiO2), silicon single crystal, iron-nickel alloy, ceramic material, sapphire and diamond, etc.

[0057] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A temperature control system for a thin film vacuum gauge, characterized in that: It comprises a heater (1), a sensor (2) and a temperature controller; The heater (1) is a cylindrical barrel structure, a control circuit board is arranged inside the side wall of the heater (1), and a thin film vacuum gauge is placed inside the heater (1); The temperature controller is electrically connected to the control circuit board, and the temperature controller controls the heater (1) to uniformly heat the thin film vacuum gauge in a constant current mode based on a preset temperature; The sensor (2) is arranged in the heater (1), the sensor (2) is electrically connected to the control circuit board, and the sensor (2) is used to detect the real-time temperature inside the heater (1) and feed back the real-time temperature to the temperature controller so that the temperature controller adjusts the heating parameters of the heater (1).

2. The temperature control system of the thin film vacuum gauge according to claim 1, characterized in that: The temperature control system of the thin film vacuum gauge further comprises a safety device (3); The safety device (3) is arranged in close contact with the outer wall of the heater (1), and the safety device (3) is electrically connected to the control circuit board.

3. The temperature control system of the thin film vacuum gauge according to claim 2, characterized in that: The safety device (3) is provided with a fuse, and the fuse is electrically connected to the control circuit board; When the sensor (2) detects that the real-time temperature inside the heater (1) is higher than a temperature threshold, the fuse blows.

4. The temperature control system of the thin film vacuum gauge according to any one of claim 1, characterized in that: The temperature controller is provided with a PID control system; The PID control system is used to calculate the temperature difference between the preset temperature and the real-time temperature, so that the temperature controller adjusts the output power of the heater (1) based on the temperature difference, so as to control the heater (1) to uniformly heat the thin film vacuum gauge based on the preset temperature in a constant current mode.

5. The temperature control system of the thin film vacuum gauge according to claim 1, characterized in that: The control circuit board is connected to a wiring device (4), the wiring device (4) is arranged on the upper edge of the side wall of the heater (1), and the temperature controller is electrically connected to the control circuit board through the wiring device (4).

6. The temperature control system of the thin film vacuum gauge according to claim 1, characterized in that: A connection hole is formed at the bottom of the inner wall of the heater (1); the sensor (2) is arranged on the bottom surface inside the heater (1) and is electrically connected to the control circuit board through the connection hole.

7. The temperature control system of the thin film vacuum gauge according to claim 1, characterized in that: The sensor (2) is prepared based on a thermocouple or a thermal resistor.

8. The temperature control system of the thin film vacuum gauge according to claim 1, characterized in that: The sensor (2) is used to detect the real-time temperature inside the heater (1), and dynamically adjust the real-time temperature inside the heater (1) based on a compensation algorithm, so as to transmit the adjusted real-time temperature to the temperature controller through the control circuit board.

9. The temperature control system of the thin film vacuum gauge according to claim 1, characterized in that: The material of the heater (1) is a flexible heating material.

10. The temperature control system of the thin film vacuum gauge according to claim 1, characterized in that: The film and the supporting structure of the thin film vacuum gauge are both made of materials with low thermal expansion coefficient.

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