Alarm ruler for measuring liquid level of liquid nitrogen

Abstract

The utility model discloses an alarm ruler for measuring the liquid level of liquid nitrogen, and belongs to the technical field of liquid level measuring instruments for dangerous chemical liquid. The alarm ruler for measuring the liquid level of the liquid nitrogen comprises an alarm module, a graduated scale, a magnetic induction structure, a magnetic floating ring and a movable positioning card, the alarm module is arranged at the top end of the graduated scale, and the magnetic induction structure is arranged at the bottom end of the graduated scale; the magnetic floating ring is oppositely arranged at one end, far away from the graduated scale, of the magnetic induction structure, and the movable positioning clamp is in relative sliding connection with the side wall of the graduated scale; the magnetic induction mechanism is electrically connected with the alarm module. When the liquid level of the liquid nitrogen is measured and the alarm ruler is inserted into the liquid level of the liquid nitrogen, the buzzer gives an alarm prompt, and the height of the liquid level from the liquid level to a liquid nitrogen tank opening can be directly measured. When the liquid nitrogen is added for use, the preset liquid level height is set, and after the volume of the liquid nitrogen reaches the preset height, an alarm is given to prompt to stop adding, so that the risk of overflow is avoided.

Description

Technical Field

[0001] This utility model belongs to the technical field of liquid level measuring instruments for hazardous chemicals, and particularly relates to an alarm ruler for measuring liquid nitrogen level. Background Technology

[0002] Liquid nitrogen is a cryogenic liquid with a boiling point of -196.56℃. Due to its unique cryogenic properties, liquid nitrogen has been widely used in many fields. In biology, medicine, and genetics, liquid nitrogen tanks are used to preserve biological samples. Liquid nitrogen can freeze biological samples to extremely low temperatures, effectively slowing down or stopping cellular metabolic processes, thereby extending the preservation time of the samples. Medical institutions and laboratories need to ensure a stable liquid level in the liquid nitrogen tank and replenish the tank with an appropriate amount of liquid nitrogen in a timely manner to prevent excessive evaporation and exposure of the samples on the liquid surface. In related technologies, the liquid level detection method in liquid nitrogen tanks mainly involves inserting an antifreeze measuring ruler into the bottom of the liquid nitrogen tank. The inspector then illuminates the interface between the liquid surface and the measuring ruler to observe and record the liquid level position, or removes the measuring ruler and determines the liquid level position based on the height of frost on the ruler. However, the small diameter of the liquid nitrogen tank makes it difficult to distinguish the boundary between the liquid nitrogen level and the measuring gauge. Furthermore, changes in room temperature after the gauge is removed can lead to inaccurate readings of the frost boundary. It's also inconvenient to monitor the liquid nitrogen level constantly during replenishment, and overflows are common during later additions. Traditional liquid level gauges are not only inefficient but also prone to safety accidents. Therefore, a technical solution is needed to improve the liquid level gauge, providing real-time alarms for detecting and controlling the amount of liquid nitrogen to be added. This device is also suitable for level detection of other hazardous chemical liquids. Summary of the Invention

[0003] The purpose of this invention is to provide a liquid nitrogen level alarm gauge, aiming to solve the problem of difficulty in detecting the level of hazardous chemicals in liquid nitrogen tanks or other opaque containers, or in reaching a set height when adding liquid nitrogen or other hazardous chemicals. Existing antifreeze liquid nitrogen level gauges suffer from inaccurate frost levels when removed from the liquid nitrogen tank due to room temperature changes, are inconvenient to observe during liquid nitrogen addition, and frequently overflow when replenishing liquid nitrogen. This invention provides a portable liquid nitrogen level alarm gauge with an alarm function, enabling confirmation of the liquid nitrogen level in the tank and real-time measurement of the liquid nitrogen level during addition or replenishment.

[0004] To achieve the above objectives, this utility model provides the following technical solution:

[0005] A liquid nitrogen level alarm gauge includes an alarm module, a scale, a magnetic induction structure, a magnetic float ring, and a movable positioning card. The alarm module is located at the top of the scale, and the magnetic induction structure is located at the bottom of the scale. The magnetic float ring is positioned opposite the end of the magnetic induction structure away from the scale. The movable positioning card is slidably connected to the side wall of the scale. The magnetic induction mechanism is electrically connected to the alarm module.

[0006] During the liquid nitrogen level detection process, the magnetic float ring is pushed by contacting the liquid nitrogen interface. After the magnetic float ring senses the magnetic induction structure, it transmits a signal to the alarm module to issue an alarm signal. The size of the scale at the time of the alarm signal is read to complete the measurement of the liquid nitrogen level.

[0007] More preferably, the scale includes a stainless steel structural body and a polytetrafluoroethylene (PTFE) coating disposed on the outer layer of the stainless steel structural body, and the readable scale lines of the scale are disposed on the PTFE coating. The PTFE coating is resistant to low temperatures and corrosion.

[0008] Preferably, the scale is provided with a grooved slide, and the movable positioning card is matched with the grooved slide, thereby realizing the sliding and engaging of the movable positioning card within the grooved slide. The movable positioning card can also employ other existing sliding and engaging structures to achieve both sliding and fixed positioning.

[0009] Preferably, when the movable positioning card is fixed at the set liquid level alarm height, the movable positioning card is fixed by a knob screw.

[0010] Preferably, the alarm module and the scale are fixedly connected, and the magnetic sensing structure is also fixedly connected to the scale. The housing of the alarm module is located at the top of the scale for easy gripping during operation. The alarm module, the scale, and the magnetic sensing structure are integrated into a single unit through a fixed connection.

[0011] Preferably, the magnetic float ring is positioned opposite the lower end of the magnetic induction switch. Specifically, the magnetic float ring moves with the rise and fall of the liquid due to buoyancy. This movement of the magnetic float ring with the liquid's rise and fall activates the magnetic induction switch, thereby sending a signal to the alarm module. More preferably, the magnetic float ring is located at 0cm on the measuring scale and can slide freely up and down by 2cm. More preferably, the magnetic float ring comprises a magnet body and a buoyancy material body disposed outside the magnet body; the buoyancy material body is preferably a polyurethane buoyancy material body.

[0012] Preferably, the magnetic induction structure includes a copper wire connecting line and a magnetic induction switch. The upper end of the copper wire connecting line is connected to the alarm module, and the lower end of the copper wire connecting line is connected to the magnetic induction switch. The copper wire connecting line is disposed between the stainless steel cylindrical structure body and the polytetrafluoroethylene coating.

[0013] Preferably, the alarm module includes a button battery, a circuit switch, a transistor, a resistor, and a buzzer. The buzzer is disposed between the positive terminal of the button battery and the collector of the transistor. The emitter of the transistor is connected to the negative terminal of the button battery. The base of the transistor is connected to one end of the resistor. The other end of the resistor is connected to one end of the magnetic induction switch via a copper wire. The other end of the magnetic induction switch is disposed between the positive terminal of the button battery and the buzzer. The circuit switch is disposed on the housing of the alarm module and can turn the alarm module on and off.

[0014] Preferably, the button battery is provided with a movable cover, through which the button battery can be replaced.

[0015] The button cell battery is preferably a CR2477 button cell battery.

[0016] The transistor is preferably an NPN type transistor.

[0017] The resistor is a 1 kΩ resistor.

[0018] The above-mentioned liquid nitrogen level alarm gauge is used as follows:

[0019] After opening the liquid nitrogen tank, the user turns on the circuit switch of the alarm module at the top of the liquid nitrogen level alarm gauge. The liquid nitrogen level alarm gauge is then held vertically downwards to detect the depth of the liquid nitrogen. When the magnetic float touches the liquid surface, it moves 2cm up from 0cm, triggering the magnetic induction switch and emitting an alarm sound, thus determining the liquid level height. Alternatively, the liquid level can be detected in real time while adding liquid nitrogen. The user opens the movable positioning clip on the side of the liquid nitrogen level alarm gauge, sets the height, and places it at the opening of the liquid nitrogen tank. Liquid nitrogen is then slowly added. When the liquid nitrogen reaches the set height, the magnetic induction switch is triggered, emitting an alarm sound and stopping the addition of liquid nitrogen to prevent overflow.

[0020] Compared with the prior art, the beneficial effects of this utility model are:

[0021] This invention relates to a liquid nitrogen level alarm gauge with a scientific and reasonable structure, and is easy to use. When measuring the liquid nitrogen level, the alarm gauge is inserted into the liquid nitrogen container, triggering an alarm. It can directly measure the liquid level height from the surface to the opening of the liquid nitrogen tank. When adding liquid nitrogen, a preset liquid level height is set. Once the liquid nitrogen volume reaches the preset height, an alarm is triggered to stop adding liquid nitrogen, preventing the risk of overflow. This invention's liquid nitrogen level alarm gauge has a simple and practical structure, and has significant practical value in laboratory applications.

[0022] This utility model relates to a liquid nitrogen level alarm ruler, comprising a stainless steel main body and a scale made of a polytetrafluoroethylene coating, a DC voltage-activated humming alarm module, a magnetic float ring, and an adjustable positioning clip for a predetermined liquid level. This invention features a simple and practical structure, capable of measuring and alarming the liquid level in real time, as well as setting a predetermined liquid level for alarm. It avoids errors in measurement results caused by subjective judgment based on liquid level marks on the ruler and the influence of objective factors, and prevents spills when adding liquid nitrogen or other hazardous chemicals. This device is not only simple in structure but also easy to operate, possessing significant practical and promotional value. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the main structure of the novel liquid nitrogen level alarm ruler used in this experiment.

[0024] Figure 2 This is a schematic diagram of the magnetic induction structure of the liquid nitrogen level alarm ruler of this utility model.

[0025] Figure 3 This is a schematic diagram of the alarm module circuit of the liquid nitrogen level alarm ruler of this utility model. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] It should be noted that if any directional indication (such as up, down, left, right, front, back, top, bottom, etc.) is involved in the embodiments of this utility model, the directional indication is only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0028] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0029] It should be noted that when a component is described as "fixed to" or "set on" another component, it can be directly on the other component or there may be an intervening component. When a component is described as "connected to" another component, it can be directly connected to the other component or there may be an intervening component.

[0030] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0031] Currently, existing antifreeze liquid nitrogen level gauges have several drawbacks when removed from the liquid nitrogen tank for observation. These include inaccurate readings of the frost boundary due to room temperature changes, inconvenience in continuous observation during liquid nitrogen replenishment, and frequent overflows during subsequent replenishment. To address these technical problems, this invention proposes a liquid nitrogen level alarm gauge.

[0032] Example 1

[0033] like Figure 1As shown, a liquid nitrogen level alarm ruler includes: an alarm module 1, a scale 2, a magnetic induction structure 3, a magnetic float ring 4, and a movable positioning card 5. The alarm module 1 is located at the top of the scale 2, and the magnetic induction structure 3 is located at the bottom of the scale 2. The magnetic float ring 4 is positioned opposite the lower end of the magnetic induction structure 3 (i.e., the magnetic float ring is positioned opposite the end of the magnetic induction structure away from the scale). The movable positioning card 5 is slidably connected to the side wall of the scale 2. The magnetic induction structure 3 is electrically connected to the alarm module 1. During liquid nitrogen level detection, the magnetic float ring 4 is pushed by contacting the liquid nitrogen interface. After the magnetic float ring 4 senses the magnetic induction structure 3, it transmits a signal to the alarm module 1 to issue an alarm signal. The scale 2 at the time of the alarm signal is read, thus completing the measurement of the liquid nitrogen level.

[0034] More preferably, the scale 2 comprises a stainless steel structural body and a polytetrafluoroethylene (PTFE) coating disposed on the outer layer of the stainless steel structural body, and the readable scale lines of the scale 2 are disposed on the PTFE coating. The PTFE coating is resistant to low temperatures and corrosion. The scale 2 is 100 cm long, and the scale increments from bottom to top, in centimeters.

[0035] Preferably, the scale 2 is provided with a grooved slide 21, and the movable positioning card 5 is matched with the grooved slide 21, thereby realizing the sliding and engaging of the movable positioning card 5 within the grooved slide 21. The movable positioning card 5 can also adopt other existing sliding and engaging structures to realize the sliding and fixed positioning of the positioning card.

[0036] Preferably, when the movable positioning card 5 is fixed at the set liquid level alarm height, it is secured by a knob screw. The length of the movable positioning card 5 is preferably 15cm. More preferably, the movable positioning card 5 can be bent at 90 degrees, folding closed to overlap with the ruler for easy carrying; the bending adopts a conventional rotary structure.

[0037] Preferably, the alarm module 1 and the scale 2 are fixedly connected, and the magnetic induction structure 3 and the scale 2 are also fixedly connected; the fixed connection method used is one of the following: snap-fit ​​connection, threaded connection, or other conventional fixed connection methods. The housing of the alarm module 1 is located at the top of the scale 2 for easy gripping during operation. Figure 1 In this configuration, the alarm module 1, the scale 2, and the magnetic induction structure 3 are integrated into a single unit through a fixed connection.

[0038] Preferably, the magnetic float ring 4 is positioned opposite the lower end of the magnetic induction structure 3. Specifically, the magnetic float ring 4 moves with the rise and fall of the liquid due to buoyancy. This movement of the magnetic float ring 4 with the liquid's rise and fall controls the switching on and off of the magnetic induction structure 3, thereby sending a signal to the alarm module 1. More preferably, the magnetic float ring 4 is located at 0cm on the measuring scale and can slide freely up and down by 2cm. More preferably, the magnetic float ring 4 comprises a magnet body and a buoyancy material body disposed on the outside of the magnet body; the buoyancy material body is preferably a polyurethane buoyancy material body.

[0039] like Figure 2 As shown, the magnetic induction structure 3 includes a copper wire connecting line 31 and a magnetic induction switch 32. The upper end of the copper wire connecting line 31 is connected to the alarm module 1, and the lower end of the copper wire connecting line 31 is connected to the magnetic induction switch 32. The copper wire connecting line 31 is disposed between the stainless steel cylindrical structure body and the polytetrafluoroethylene coating.

[0040] like Figure 3 As shown, the alarm module 1 includes a button battery 11, a circuit switch 12, a transistor 13, a resistor 14, and a buzzer 15. The buzzer 15 is disposed between the positive terminal of the button battery 11 and the collector of the transistor 13. The emitter of the transistor 13 is connected to the negative terminal of the button battery 11, and the base of the transistor is connected to one end of the resistor 14. The other end of the resistor 14 is connected to one end of the magnetic induction switch 32 via the copper wire connecting line 31. The other end of the magnetic induction switch 32 is disposed between the positive terminal of the button battery 11 and the buzzer 15. The circuit switch 12 is disposed on the housing of the alarm module 1, and the circuit switch 12 can turn the alarm module on and off.

[0041] Preferably, the button battery is provided with a movable cover, through which the button battery can be replaced.

[0042] The button cell 11 is preferably a CR2477 button cell.

[0043] The transistor 13 is preferably an NPN type transistor.

[0044] The resistor is a 1 kΩ resistor.

[0045] The above-mentioned liquid nitrogen level alarm gauge is used as follows:

[0046] After opening the liquid nitrogen tank, the user turns on the circuit switch 12 of the alarm module 1 at the upper end of the liquid nitrogen level alarm ruler. The liquid nitrogen level alarm ruler is then placed vertically downwards to detect the depth of the liquid nitrogen. When the magnetic float 4 touches the liquid surface, it moves 2cm up from 0cm to trigger the magnetic induction switch 32, and the buzzer 15 sounds an alarm, thus determining the liquid level height. Alternatively, the liquid level height can be detected in real time when adding liquid nitrogen. The movable positioning clip 5 on the side of the liquid nitrogen level alarm ruler is opened, the height is set, and it is clipped into the liquid nitrogen tank opening. Liquid nitrogen is then slowly added. When the liquid nitrogen reaches the set height, the magnetic induction switch 32 is triggered, the buzzer 15 sounds an alarm, and the addition of liquid nitrogen is stopped to prevent liquid nitrogen from overflowing.

[0047] It should be noted that, for those skilled in the art, this utility model is not limited to the details of the above exemplary embodiments. Several modifications and improvements can be made without departing from the concept of this utility model, or it can be used for level detection of other liquid hazardous chemicals; all of these fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

[0048] Compared with the prior art, the beneficial effects of this utility model are:

[0049] This invention relates to a liquid nitrogen level alarm gauge with a scientific and reasonable structure, and is easy to use. When measuring the liquid nitrogen level, the alarm gauge is inserted into the liquid nitrogen container, triggering an alarm. It can directly measure the liquid level height from the surface to the opening of the liquid nitrogen tank. When adding liquid nitrogen, a preset liquid level height is set. Once the liquid nitrogen volume reaches the preset height, an alarm is triggered to stop adding liquid nitrogen, preventing the risk of overflow. This invention's liquid nitrogen level alarm gauge has a simple and practical structure, and has significant practical value in laboratory applications.

[0050] This utility model relates to a liquid nitrogen level alarm ruler, comprising a stainless steel main body and a scale made of a polytetrafluoroethylene coating, a DC voltage-activated humming alarm module, a magnetic float ring, and an adjustable positioning clip for a predetermined liquid level. This invention features a simple and practical structure, capable of measuring and alarming the liquid level in real time, as well as setting a predetermined liquid level for alarm. It avoids errors in measurement results caused by subjective judgment based on liquid level marks on the ruler and the influence of objective factors, and prevents spills when adding liquid nitrogen or other hazardous chemicals. This device is not only simple in structure but also easy to operate, possessing significant practical and promotional value.

[0051] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A liquid nitrogen level alarm gauge, characterized in that: The device includes an alarm module, a scale, a magnetic induction structure, a magnetic float ring, and a movable positioning card. The alarm module is located at the top of the scale, and the magnetic induction structure is located at the bottom of the scale. The magnetic float ring is positioned opposite the end of the magnetic induction structure away from the scale. The movable positioning card is slidably connected to the side wall of the scale. The magnetic induction structure is electrically connected to the alarm module.

2. The liquid nitrogen level alarm gauge according to claim 1, characterized in that: The scale includes a stainless steel structural body and a polytetrafluoroethylene coating disposed on the outer layer of the stainless steel structural body, and the readable scale lines of the scale are disposed on the polytetrafluoroethylene coating.

3. The liquid nitrogen level alarm gauge according to claim 1, characterized in that: The scale is provided with a grooved slide, and the movable positioning card is matched with the grooved slide to realize the sliding and engaging of the movable positioning card in the grooved slide.

4. The liquid nitrogen level alarm gauge according to claim 1, characterized in that: The alarm module is fixedly connected to the scale, and the magnetic induction structure is fixedly connected to the scale.

5. The liquid nitrogen level alarm gauge according to claim 2, characterized in that: The magnetic sensing structure includes a copper wire connecting line and a magnetic sensing switch. The upper end of the copper wire connecting line is connected to the alarm module, and the lower end of the copper wire connecting line is connected to the magnetic sensing switch. The copper wire connecting line is disposed between the stainless steel structural body and the polytetrafluoroethylene coating.

6. The liquid nitrogen level alarm gauge according to claim 5, characterized in that: The alarm module includes a button battery, a circuit switch, a transistor, a resistor, and a buzzer. The buzzer is positioned between the positive terminal of the button battery and the collector of the transistor. The emitter of the transistor is connected to the negative terminal of the button battery. The base of the transistor is connected to one end of the resistor. The other end of the resistor is connected to one end of the magnetic induction switch via a copper wire. The other end of the magnetic induction switch is positioned between the positive terminal of the button battery and the buzzer.

7. The liquid nitrogen level alarm gauge according to claim 6, characterized in that: The button battery has a movable cover, which allows the button battery to be replaced.

8. The liquid nitrogen level alarm gauge according to claim 6, characterized in that: The button cell battery is a CR2477 button cell battery.

9. The liquid nitrogen level alarm gauge according to claim 6, characterized in that: The transistor is an NPN type transistor.

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