Cold trap level measuring device and alarm apparatus

Abstract

This invention provides a cold trap liquid level measuring device and alarm equipment, solving the problem that traditional liquid level gauges cannot adapt to the cold trap environment due to poor environmental adaptability, easily damaged mechanical structure, and weak anti-interference ability. The measuring device includes: a composite measuring rod filled with dry air, which is inserted into the cold trap during measurement; a pressure tube filled with dry air at standard atmospheric pressure and connected to the composite measuring rod; a connecting assembly for fixing and sealing the composite measuring rod and the pressure tube; a pressure sensor including a housing and a circuit board disposed within the housing, the circuit board integrating a pressure element and a first microcontroller, and a display screen on the surface of the housing; the pressure element measures the pressure value in the pressure tube in real time and calculates the liquid level height in the cold trap in conjunction with the first microcontroller, and the liquid level height information is analyzed by the first microcontroller and displayed on the display screen; and a sealing flange for connecting and sealing the pressure tube and the pressure sensor.

Description

Technical Field

[0001] This utility model relates to a cold trap liquid level measuring device, which is particularly suitable for special media environments with high conductivity, strong corrosiveness, and suspended particles. Background Technology

[0002] A cold trap is a device that condenses gas or vapor on a low-temperature surface and is widely used in vacuum systems, precision instruments, and high-end equipment. Its core function is to provide an extremely low-temperature environment (typically -40°C to -80°C) to trap volatile substances (such as water vapor and organic solvents), preventing them from entering the vacuum pump or experimental system, thereby protecting the equipment, maintaining vacuum levels, and improving experimental accuracy. Cold traps are commonly used in vacuum coating, freeze dryers, chemisorption analyzers, and photochemical reactors, and are key components ensuring the stable operation of the system.

[0003] As a core cryogenic component in precision instruments and high-end equipment, the operational stability of cold traps directly depends on the efficient cooling capacity of liquid nitrogen or liquid helium. Real-time monitoring of the liquid level is not only fundamental to maintaining the system's cryogenic environment but also a crucial link in ensuring equipment operational safety and the reliability of experimental data. Abnormal liquid levels (such as excessively low levels) will lead to a sharp drop in cooling efficiency, potentially causing equipment performance degradation, distorted experimental data, and even irreversible damage to system components due to localized overheating or thermal stress. Therefore, constructing a high-precision, dynamically responsive liquid level monitoring system is of decisive significance for the application of cold traps.

[0004] Existing general-purpose liquid level measurement technologies face significant adaptability challenges in cold trap scenarios: While capacitive level gauges offer a wide temperature measurement range (-40°C to 600°C), their sensitivity to liquid level fluctuations is insufficient, making them ill-suited to handle dynamic liquid level changes caused by medium evaporation and bubble disturbances in cold traps, resulting in measurement lag and error accumulation. Float-type level gauges are susceptible to corrosion from liquid nitrogen / helium scaling and crystallization, leading to decreased reliability over long-term operation and high maintenance costs. Ultrasonic level gauges are limited by vacuum environment compatibility and pressure vessel sealing requirements; their sound wave propagation is easily interfered with by liquid surface foam layers and vapor condensation films, resulting in frequent false echoes and measurement accuracy failing to meet industrial-grade requirements. Addressing these technical bottlenecks, the development of level gauges specifically designed for cold trap environments has become an urgent industry need. Utility Model Content

[0005] This invention proposes a cold trap liquid level measuring device, which solves the problem that traditional liquid level gauges cannot adapt to the cold trap environment due to poor environmental adaptability, easy damage to mechanical structure, and weak anti-interference ability.

[0006] In a first aspect, a cold trap liquid level measuring device is proposed, comprising: a composite measuring rod filled with dry air, inserted into the cold trap during measurement; a pressure tube filled with dry air at standard atmospheric pressure at room temperature, connected to the composite measuring rod; a connecting assembly for fixing and sealing the composite measuring rod and the pressure tube; a pressure sensor including a housing and a circuit board disposed within the housing, the circuit board integrating a pressure element and a first microcontroller, a display screen on the surface of the housing, the pressure element measuring the pressure value in the pressure tube in real time, and calculating the liquid level height in the cold trap in conjunction with the first microcontroller, the liquid level height information being parsed by the first microcontroller and displayed on the display screen; and a sealing flange for connecting and sealing the pressure tube and the pressure sensor.

[0007] In some examples, the composite measuring rod employs a telescopic structure, and the measurement depth is adjusted through a sliding connection between the inner and outer sleeves.

[0008] In some examples, the telescopic structure is a double-sleeve structure or a spiral adjustment structure.

[0009] In some examples, the composite measuring rod is made of a composite material of polyetheretherketone (PEEK) and polytetrafluoroethylene (PTFE).

[0010] In some examples, the housing of the pressure sensor is made of polyethylene, polyvinyl chloride, or polypropylene.

[0011] In some examples, the connecting components are made of copper alloy or stainless steel.

[0012] In some examples, the air pressure pipe is made of copper alloy or stainless steel.

[0013] In some examples, the connecting assembly connects the composite measuring rod and the pneumatic tube via threads and uses a rubber gasket to achieve a seal; the sealing flange connects the pneumatic tube and the pneumatic sensor via threads and uses a rubber gasket to achieve a seal.

[0014] Secondly, a cold trap liquid level alarm device is proposed, comprising: an alarm; a camera for capturing real-time images of the display screen of the cold trap liquid level measuring device to obtain image data of liquid level information; and a second microcontroller connected to the camera and the alarm, identifying the cold trap liquid level from the image data, and triggering the alarm when the liquid level is higher than the upper limit or lower than the lower limit.

[0015] In some examples, the alarm is an LED light.

[0016] This invention's cold trap liquid level measuring device breaks through the limitations of traditional capacitive measurement technology, achieving high-precision liquid level measurement over an ultra-wide temperature range; it adopts a medium-independent design principle, making it suitable for various liquid types and different ambient temperature conditions; it has a compact structure and reliable performance, while also being small in size and adaptable to measurement in confined spaces such as narrow pipes. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a cold trap liquid level measuring device in one embodiment of the present invention. Detailed Implementation

[0018] Figure 1 A cold trap liquid level measurement device is demonstrated. Based on the thermodynamic properties of a closed gas column, this device can achieve accurate liquid level measurement over an ultra-wide temperature range through a temperature-pressure dynamic coupling model.

[0019] like Figure 1 As shown, the device includes a composite measuring rod 1, a connecting assembly 2, a pneumatic tube 3, a sealing flange 4, and a pneumatic sensor 5.

[0020] The composite measuring rod 1 is filled with dry air and adopts a telescopic structure design. The measurement depth can be flexibly adjusted through the sliding connection between the inner and outer sleeves. The telescopic structure of this utility model is not limited to a specific form. For example, it can adopt conventional technical solutions such as a double-sleeve structure (with the inner and outer layers sliding together) or a screw adjustment structure, which are common knowledge to those skilled in the art.

[0021] The composite measuring rod 1 is preferably made of a composite material of polyetheretherketone (PEEK) and polytetrafluoroethylene (PTFE). This material combination has high wear resistance, low coefficient of friction, and excellent chemical stability, which can effectively extend the service life of the measuring rod and improve measurement accuracy. The composite measuring rod 1, as a sensing component, is inserted into the cold trap during measurement. Due to its tubular structure design, the measuring device of this invention can be adapted to measurement environments in confined spaces such as narrow pipes.

[0022] The connecting component is a fixed connector between the composite measuring rod and the air pressure tube. It is fixed by threads and sealed by rubber gaskets. The connecting component is made of materials such as copper alloy or stainless steel.

[0023] The connecting component 2 is the connection structure between the composite measuring rod 1 and the pneumatic tube 3, which is sealed and fixed by a threaded connection and a rubber gasket. The material of the connecting component 2 is preferably copper alloy or stainless steel, which has good corrosion resistance and sealing performance, and can ensure a stable connection and long-term reliability at the interface between the measuring rod 1 and the pneumatic tube 3.

[0024] The air pressure pipe 3 is filled with dry air at standard atmospheric pressure to prevent internal condensation or corrosion. Its material is preferably copper alloy or stainless steel, which has good corrosion resistance and sealing performance, and can ensure long-term stable operation of the system.

[0025] The sealing flange 4 serves as the connection structure between the pressure pipe 3 and the pressure sensor 5, achieving a seal through a threaded connection and a rubber gasket. Its material is preferably copper alloy or stainless steel, offering excellent corrosion resistance and sealing performance, ensuring a stable connection and long-term reliability at the interface.

[0026] The pressure sensor 5 measures the pressure inside the pressure tube 3 in real time. Combined with the analysis of the difference between the measured pressure and the standard atmospheric pressure by the first microcontroller, the built-in algorithm calculates the liquid level in the cold trap. This type of pressure-to-liquid-level conversion algorithm is common knowledge to those skilled in the art. For example, the height algorithm model is H = (P... θ -P)*κλ, where H is the liquid level height, P θ Where is standard atmospheric pressure, P is the measured air pressure value of the sensor, κ is the influencing factor, and λ is the liquid coefficient.

[0027] The pressure sensor 5 includes a housing and a circuit board disposed within the housing. The circuit board integrates a pressure element, a first microcontroller, and a pressure signal acquisition circuit. A display screen is provided on the surface of the housing. The housing is preferably made of polyethylene (PE), polyvinyl chloride (PVC), or polypropylene (PP), which are lightweight, corrosion-resistant, and easy to process. The pressure element senses pressure changes in the gas environment within the pressure tube 3 and outputs a corresponding signal. The first microcontroller analyzes the pressure signal and ultimately generates liquid level information. The liquid level information is displayed on the display screen. It should be noted that the circuit board design of the pressure sensor 5 (such as signal acquisition and data processing modules) is common knowledge in the field, and its specific circuit implementation methods are all existing conventional technologies.

[0028] In addition, wireless transmission units (such as LoRa and NB-IoT) can be integrated on the circuit board to send liquid level data to the cloud platform in real time, allowing users to remotely monitor liquid level status information through terminals (such as mobile phones).

[0029] As can be seen, the composite measuring rod 1, connecting component 2, air pressure pipe 3, sealing flange 4 and air pressure sensor 5 are connected in sequence to form an integral structure, thereby achieving a compact design and small size of the device.

[0030] The present invention also provides a cold trap liquid level alarm device for reading the liquid level data output by the cold trap liquid level measuring device and triggering an alarm when the liquid level exceeds a set threshold range (upper limit or lower limit).

[0031] The alarm device includes a camera, a second microcontroller, and an alarm. The camera captures real-time images of the cold trap liquid level measurement device's display screen to obtain liquid level information.

[0032] The second microcontroller integrates a conversion module and an intermediate processing module. The conversion module uses an image recognition algorithm to convert the liquid level image captured by the camera into binary data b, and extracts the liquid level numerical features through pixel-by-pixel analysis. The intermediate processing module performs filtering, grouping, association, and aggregation processing on the binary data b based on conditional judgment logic to generate early warning data (such as liquid level abnormality status indicators). It should be noted that the technical means used by the conversion module and the intermediate processing module (such as image recognition algorithms, data filtering and aggregation methods) are common knowledge in the field, and their technical basis and implementation methods are all existing conventional technologies.

[0033] The alarm is an LED light that receives warning data from the intermediate processing module and performs alarm rule judgments. For example, when the warning data meets the preset alarm conditions (such as the liquid level being higher than the upper limit or lower than the lower limit), the red LED light is triggered to flash.

Claims

1. A cold trap liquid level measuring device, characterized in that, include: The composite measuring rod uses a telescopic structure to adjust the measuring depth, is filled with dry air, and is inserted into the cold trap during measurement. The air pressure tube is filled with dry air at standard atmospheric pressure and is connected to the composite measuring rod. A connecting assembly for securing and sealing the composite measuring rod to the pneumatic tube; A pressure sensor includes a housing and a circuit board disposed within the housing. The circuit board integrates a pressure element and a first microcontroller. A display screen is provided on the surface of the housing. The pressure element measures the air pressure in a pressure tube in real time and calculates the liquid level in the cold trap using the first microcontroller. The liquid level information is parsed by the first microcontroller and displayed on the display screen. A sealing flange is used to connect and seal the pressure pipe to the pressure sensor.

2. The cold trap liquid level measuring device according to claim 1, characterized in that, The composite measuring rod achieves depth adjustment through a sliding connection between the inner and outer sleeves.

3. The cold trap liquid level measuring device according to claim 2, characterized in that, The telescopic structure is a double-layer sleeve structure or a spiral adjustment structure.

4. The cold trap liquid level measuring device according to claim 1, characterized in that, The composite measuring rod is made of a composite material of polyetheretherketone and polytetrafluoroethylene.

5. The cold trap liquid level measuring device according to claim 1, characterized in that, The housing of the pressure sensor is made of polyethylene, polyvinyl chloride, or polypropylene.

6. The cold trap liquid level measuring device according to claim 1, characterized in that, The connecting components are made of copper alloy or stainless steel.

7. The cold trap liquid level measuring device according to claim 1, characterized in that, The air pressure pipe is made of copper alloy or stainless steel.

8. The cold trap liquid level measuring device according to claim 1, characterized in that, The connecting assembly connects the composite measuring rod and the air pressure pipe via threads and uses a rubber gasket to achieve a seal; the sealing flange connects the air pressure pipe and the air pressure sensor via threads and uses a rubber gasket to achieve a seal.

9. A cold trap liquid level alarm device, characterized in that, include: Alarm; A camera is used to capture image data of the liquid level measurement device of the cold trap according to any one of claims 1-8 in real time, and to acquire liquid level information. The second microcontroller is connected to the camera and the alarm, identifies the cold trap liquid level from the image data, and triggers the alarm when the liquid level is higher than the upper limit or lower than the lower limit.

10. The cold trap liquid level alarm device according to claim 9, characterized in that, The alarm is an LED light.

Images