Standard Gas Generator

Abstract

The present invention comprises: a mass flow meter (100) that supplies a carrier gas at a constant flow rate; a hermetic constant temperature chamber (200) connected to a gas inlet pipe (110) through which the carrier gas flows in from one side through the mass flow meter (100), and which is connected to a reference gas discharge pipe (210) on the other side after being mixed with a vaporized gas inside; a simulant vaporization unit (300) that stores, heats, and vaporizes a liquid simulant; and a cylinder (700) that raises and lowers the simulant vaporization unit (300) to be combined with or separated from the hermetic constant temperature chamber (200). The present invention relates to a standard gas generator capable of rapidly and stably providing highly reproducible standard gas while maintaining a constant concentration of reference gas for a long period of time through stable vaporization in a simulant vaporization section, efficient gas transfer using negative pressure, precise mixing in a dual injection channel, and automatic feedback control based on a concentration analyzer.

Description

Technology Field

[0001] The present invention relates to a standard gas generator that generates a standard gas of a target concentration and flow rate by vaporizing a liquid simulant.

[0002] More specifically, the invention relates to a technology for stably diluting and mixing a liquid simulant in a vaporized state by utilizing the suction and mixing action of an air jet.

[0003] In addition, the present invention belongs to the field of vaporization and mixing technology for continuously and precisely generating reference gases used in analytical equipment calibration, environmental measurement, exhaust gas testing, etc. Background Technology

[0005] Recently, the importance of technology for stably generating standard gases (or reference gases) with a constant concentration and flow rate for equipment calibration and performance verification has been significantly highlighted in various analytical instruments, environmental measuring instruments, automotive exhaust gas measuring devices, semiconductor and precision process equipment, etc.

[0006] Since such standard gases are essential for ensuring the accuracy, reactivity, and repeatability of measuring equipment, various types of standard gas generators have been proposed.

[0007] As one of the conventional standard gas manufacturing technologies, Prior Art 1 presents a device for producing low-concentration standard gas in a mixing space by ejecting gas through micro-holes from a cylinder storing high-concentration gas and flowing zero gas around it. However, this method has limitations in that the device becomes large because both high-concentration and zero-concentration gas cylinders must be used, and the structure is complex and the burden of operation and maintenance is high because the dilution ratio relies entirely on a mass flow meter (MFC).

[0008] Another prior art document, Prior Art 2, discloses a diffusion-based standard gas production system. This method involves delivering sample components to a product container at a constant diffusion rate through a gas permeable membrane, and then injecting purified gas to produce a primary standard gas of ultra-low concentration. However, the diffusion-based static method is sensitive to temperature, diffusion membrane characteristics, and system closure conditions, and the reaction time is very long, making it difficult to change the concentration and unsuitable for the generation of dynamic standard gases that control concentration in real time.

[0009] Meanwhile, prior art document 3 presents a standard gas production device that vaporizes a liquid sample and mixes it with a diluent gas. This device is structured to mix the vaporized sample and the diluent gas using a vacuum by connecting a diluent gas supply unit, a liquid sample vaporization unit, a mixing unit, and a storage tank through multiple pipes and valves. However, due to complex components such as multiple valves, vacuum pumps, and storage tanks, the device is large and manufacturing costs increase, and there are problems with poor maintenance and field applicability due to the complex piping and control structures.

[0010] In addition, prior art documents 4 and 7 disclose a technique for generating a standard gas by injecting a liquid sample into a vaporization unit using a syringe or metering pump and mixing it with a diluent gas. While this technique allows a small amount of injected liquid to vaporize at a constant rate to form a concentration, the amount of liquid injected is significantly affected by the driving precision of the syringe or pump. Furthermore, repeatability is reduced depending on changes in the temperature conditions of the vaporization unit, and there are limitations in continuously varying the concentration to generate a standard gas. In particular, the liquid injection method can cause operational problems such as condensation in the piping, sample adsorption, and nozzle clogging, which can lead to instability in experimental repeatability.

[0011] Meanwhile, prior art documents 5 and 6 present a standard gas mixing technology that precisely controls and mixes multiple high-concentration gases using a mass flow controller. Although such devices enable relatively accurate concentration control by including various control elements such as an MFC, static mixer, temperature controller, and pipe heating unit, the device configuration itself is complex and costly. Furthermore, because it requires large gas panels and various gas cylinders, it is difficult to apply in environments requiring miniaturization, mobility, and easy operation. Additionally, since it does not include a structure for directly vaporizing and mixing liquid samples or samples of various forms, it is difficult to satisfy the flexibility required in diverse field environments.

[0012] Existing standard gas generators based on such prior art had problems such as i) requiring large high-concentration, zero-gas cylinders, making the device complex; ii) slow concentration adjustment speed and difficulty in real-time control due to the diffusion-based static method; iii) difficulty in operation and maintenance due to the complex system consisting of multiple valves, pumps, and piping; and iv) problems with condensation, adsorption, and repeatability in the liquid sample injection method.

[0013] In particular, there is a continuously growing need for a compact, simple, and highly reliable standard gas generator that can rapidly and stably vaporize liquid simulants or liquid samples and mix them with diluent gases, while having a simple structure, eliminating problems such as backflow or condensation, and allowing for continuous concentration control.

[0014] Therefore, there is a need to develop a novel standard gas generator that solves these problems of conventional technology, safely and stably vaporizes liquid samples to rapidly generate standard gas while simplifying the structure through the suction and mixing action of an air ejector, and offers excellent concentration control and repeatability. Prior art literature

[0016] Prior Art 1 Korean Utility Model Publication No. 20-1999-0027681 (Published July 15, 1999) Prior Art 2 Korean Patent Registration No. 10-1367575 (Published February 25, 2014) Prior Art 3 Korean Patent Registration No. 10-1779292 (Published September 18, 2017) Prior Art 4 Korean Patent Registration No. 10-0656415 (Published December 11, 2006) Prior Art 5 Korean Patent Registration No. 10-1225042 (Published January 16, 2013) Prior Art 6 Korean Patent Publication No. 10-2013-0033646 (Published April 4, 2013) Prior Art 7 Korean Patent Registration No. 10-1913310 (Notice on Oct. 24, 2018) The problem to be solved

[0017] Accordingly, the present invention has been devised to resolve the aforementioned problems, and the present invention aims to provide a standard gas generator with a simple and stable structure capable of continuously generating standard gas without complex piping or vacuum systems by safely and reliably vaporizing a liquid simulant.

[0018] Furthermore, the present invention aims to eliminate problems that frequently occurred in conventional technology, such as backflow, condensation, and non-uniform mixing of liquid simulants, by utilizing the suction and mixing functions of an air jet, and to provide a standard gas generation method with excellent responsiveness to concentration fluctuations.

[0019] Furthermore, another objective of the present invention is to provide a highly reproducible standard gas generation technology capable of precisely controlling and generating standard gases of various concentration ranges while ensuring the miniaturization of the entire device and ease of maintenance. means of solving the problem

[0021] The present invention has been devised to achieve the above-mentioned purpose, and

[0022] A mass flow meter (100) that supplies carrier gas at a constant flow rate;

[0023] A hermetic constant temperature chamber (200) in which the carrier gas is connected to a gas inlet pipe (110) through which the carrier gas is introduced from one side via the mass flow meter (100), and after being mixed with vaporized gas inside, is connected to a reference gas discharge pipe (210) on the other side;

[0024] A simulant vaporization unit (300) that stores, heats, and vaporizes a liquid simulant;

[0025] A cylinder (700) that raises and lowers the above simulant vaporization unit (300) to be combined with or separated from the above airtight constant temperature chamber (200);

[0026] A standard gas generator based on an air-jector liquid simulant vaporization is presented. Effects of the invention

[0028] According to the present invention, since the liquid simulant can be stably diluted and mixed in a vaporized state by utilizing the suction and mixing action of an air ejector, problems such as liquid backflow, condensation, and non-uniform mixing that occurred in conventional bubble methods or vacuum-based vaporization methods are effectively prevented.

[0029] In addition, the present invention does not require complex piping, multiple valves, vacuum pumps, etc., which enables the simplification of the device configuration. Consequently, it has the effect of significantly improving device miniaturization, manufacturing cost reduction, and ease of maintenance.

[0030] In addition, since the vaporization amount and mixing ratio of the simulant can be continuously controlled solely by controlling the air ejector drive flow rate or pressure, there is an advantage in that standard gas within the target concentration range can be generated quickly and precisely.

[0031] Furthermore, the device of the present invention can ensure high repeatability by minimizing concentration deviations caused by temperature fluctuations or changes in piping conditions, and has the effect of being suitable for providing stable reference gases in various application fields such as environmental analysis, exhaust gas measurement, and equipment calibration. Brief explanation of the drawing

[0033] FIG. 1 is a drawing that schematically illustrates the overall configuration of the present invention. FIG. 2 is a drawing showing the state in FIG. 1 with the support removed. FIG. 3 is a diagram schematically illustrating the connection state of a metering pump, a concentration analyzer, and a concentration control unit in a standard gas vaporization device according to the present invention. FIG. 4 is a diagram schematically illustrating the flow path state inside the simulant vaporization unit and the hermetic constant temperature chamber in the present invention. FIG. 5 is an enlarged view of section 'A' in FIG. 4. Specific details for implementing the invention

[0034] It should be noted that the structural or functional descriptions of the embodiments of the present invention disclosed in this specification are provided for illustrative purposes only.

[0035] The present invention may be embodied in various forms and is not limited to the contents described in this specification, but includes all modifications, equivalents, or substitutions made within the technical spirit and scope of the present invention. Furthermore, terms or words used in this specification and claims should not be interpreted restrictively according to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, in accordance with the principle that an inventor may appropriately define the concept to optimally describe their invention.

[0036] The embodiments described in this specification and the configurations illustrated in the accompanying drawings are merely the most preferred embodiments of the present invention and do not represent the entirety of the technical concept of the present invention. Therefore, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0037] Furthermore, unless otherwise defined in this specification, all terms, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms defined in general dictionaries should be interpreted in a meaning consistent with their contextual meaning in the relevant technical field and, unless explicitly defined in this specification, should not be interpreted in an ideal or overly formal sense.

[0039] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0041] As shown in the attached drawings, the standard gas generating device of the present invention comprises a mass flow meter (100) that supplies a carrier gas at a constant flow rate, a hermetic constant temperature chamber (200) having a flow path for mixing the carrier gas and the vaporized gas, a simulant vaporization unit (300) that stores, heats, and vaporizes a liquid simulant, a cylinder (700) that combines or separates a liquid storage container (333) contained inside the simulant vaporization unit (300) and a supporting coupling unit (350) that supports the simulant vaporization unit (300), and a standard gas discharge pipe (210) that discharges a standard gas.

[0042] Additionally, the simulant vaporization unit (300) is configured with an outer container (320), an inner container (330), a liquid storage container (333), a bubble generating unit (331), a heater (321), a negative pressure gas suction pipe (332), a liquid injection pipe (217) connected to a metering pump (500), and a double injection flow path (216) surrounding it from the outside.

[0043] In addition, a mixing channel (213) in which a carrier gas and a vaporized simulant gas are mixed is formed inside the airtight constant temperature chamber (200), connecting the gas inlet pipe (110) and the reference gas discharge pipe (210), and when this mixed gas satisfies the reference concentration, it is supplied to the outside through the reference gas discharge pipe (210).

[0044] Additionally, the concentration of the generated reference gas is measured by a concentration analyzer (400), and the measured value is used to automatically control the operation of the heater (321) or the metering pump (500) by the concentration control unit (600).

[0045] The term “carrier gas” as described above in the specification of the present invention refers to a concept comprising air, nitrogen (N₂), or an equivalent inert gas, as a carrier gas for transporting the simulant gas vaporized in the simulant vaporization unit (300) to the mixing channel (213) of the hermetically sealed constant temperature chamber (200).

[0047] As such, the standard gas generator according to the present invention is largely composed of a gas supply system, a hermetic constant temperature chamber and mixing system, a simulant vaporization unit, a control and analysis system, and a driving system.

[0049] First, the gas supply system consists of a mass flow meter (100) and a gas inlet pipe (110).

[0050] The mass flow meter (100) stably supplies carrier gas at a constant flow rate, and the gas inlet pipe (110) can be described as a pipe that transmits the carrier gas introduced from the mass flow meter (100) to one side of the mixing pipe (213) provided inside the airtight constant temperature chamber (200).

[0051] Such a mass flow meter (100) accurately supplies the carrier gas at a specified flow rate to form the basic concentration conditions for the generation of the reference gas. The gas inlet pipe (110) delivers this carrier gas without loss into the aforementioned mixing pipe (213) of the hermetic constant temperature chamber (200).

[0053] The above-mentioned airtight constant temperature chamber (200) is a space that forms a flow path for generating a reference gas by mixing the carrier gas and the vaporized gas generated in the simulant vaporization unit (300). As described above, the mixing flow path pipe (213) is formed inside the chamber to allow for the flow and mixing of the gas, and the mixed reference gas is discharged to the outside through a reference gas discharge pipe (210) connected to the other side of the chamber.

[0054] In addition, a connecting part (220) for coupling with a simulant vaporization part (300) is provided at the bottom of the above-mentioned airtight constant temperature chamber (200), and through this connecting part (220), the internal flow path of the airtight constant temperature chamber (200) and the internal space of the simulant vaporization part (300) are connected.

[0055] In addition, a double injection pipe (216), a liquid injection pipe (217), and a vaporization gas discharge pipe (215) connected to the aforementioned mixing pipe (213) are arranged in the flow path formed inside the above-mentioned airtight constant temperature chamber (200), thereby forming a structure that connects the simulant vaporization unit (300) and the flow path inside the chamber.

[0056] In this way, the hermetic constant temperature chamber (200) maintains the flow of carrier gas in a constant temperature environment, and at the same time, generates a reference gas by mixing the vaporized gas introduced from the simulant vaporization unit (300) through the internal flow path of the hermetic constant temperature chamber (200), and the mixing flow path (213) inside the hermetic constant temperature chamber (200) stabilizes the flow of the vaporized gas to ensure uniformity of the mixing concentration.

[0058] The above simulant vaporization unit (300) is a module for storing, heating, and vaporizing a liquid simulant and is composed of a storage unit (310), an outer container (320), an inner container (330), and a liquid storage container (333).

[0059] A heater (321) is installed in the outer container (320) to maintain a constant temperature of the inner container (330), and a bubble generating unit (331) is positioned at the bottom of the inner container (330) to generate bubbles in the stored simulant to increase vaporization efficiency.

[0060] In addition, the vaporized gas generated inside the above simulant vaporization unit (300) rises to the side of the vaporized gas discharge pipe (215) connected to the gas inlet pipe (110) at the top of the liquid storage container (333) of the storage unit (310), as seen in FIGS. 4 and 5.

[0061] The simulant vaporization unit (300) can heat the liquid simulant stored in the liquid storage container (333) by the heater (321) and increase the vaporization rate of the simulant through bubbles formed by the bubble generation unit (331). The vaporized simulant is transported upward through the vaporization gas discharge pipe (215) at the top of the inner container (330), which forms the storage unit (310) provided within the inner container (330), and undergoes a series of processes in which it is mixed with the carrier gas supplied from the mass flow meter (100) through the aforementioned mixing flow pipe (213).

[0062] As shown in FIG. 5, the flow path configured inside the above-mentioned airtight constant temperature chamber (200) forms a primary flow path in which the carrier gas introduced from the mass flow meter (100) through the gas inlet pipe (110) is guided toward the mixing flow path pipe (213) and discharged through the reference gas discharge pipe (210) connected to the other end of the mixing flow path pipe (213).

[0063] However, if the concentration of the gas does not reach the set concentration as a result of analysis by the concentration analyzer (400) described later before being discharged through the reference gas discharge pipe (210), a small amount of liquid or gaseous gas is configured to be introduced through the liquid injection pipe (217) inside the double injection flow path (216) via the metering pump (500) described later, and the carrier gas flowing through the mixing flow path (213) is introduced into the connecting pipe (214) through the connecting pipe (214) connecting the double injection flow path (216) and the mixing flow path (213), and after being guided toward the double injection flow path (216), is configured to be introduced toward the negative pressure gas suction pipe (332) connected to the bubble generation part (331) of the liquid storage container (333) provided in the inner container (330).

[0065] Additionally, the Euro connection and concentration control system consists of a double injection pipe (216), a liquid injection pipe (217), a vaporized gas discharge pipe (215), and a metering pump (500).

[0066] The above liquid injection pipe (217) is connected to a metering pump (500) to precisely supply a small amount of liquid simulant, and this liquid is supplied into the interior of the double injection channel (216).

[0067] The above-mentioned liquid injection pipe (217) is coaxially arranged inside the double injection channel (216) as described above.

[0068] The above-mentioned double injection channel (216) forms a channel that is orthogonally connected to the above-mentioned mixing channel (213) and connecting channel (214) on one side, and forms a channel on the other side, the end side, that is connected to the negative pressure gas suction channel (332).

[0069] In addition, the liquid injection pipe (217) allows a small amount of liquid or gas simulant supplied by the metering pump (500) to flow into the double injection flow path (216). This enables a series of processes in which, when the concentration of the gas moving through the mixing flow path (213) does not match the standard gas setting concentration and adjustment is required, the gas flowing through the mixing flow path (213) is guided toward the connecting pipe (214), then moved downward toward the bubble generation part (331) of the liquid storage container (333) through the negative pressure gas suction pipe (332) where negative pressure is formed, and then guided toward the vaporized gas discharge pipe (215) to be mixed with the mixing flow path (213).

[0070] That is, for this purpose, the upper end of the double injection channel (216) is connected to the mixing channel (213) of the airtight constant temperature chamber (200), and the lower end is connected to the negative pressure gas suction channel (332) inside the simulant vaporization unit (300).

[0072] Accordingly, the vaporized gas formed in the simulant vaporization unit (300) first moves to the mixing flow path (213) through the vaporized gas discharge pipe (215) and is mixed with the carrier gas, and the concentration of the reference gas is adjusted through the flow path, and then finally discharged through the reference gas discharge pipe (210), thereby having a series of fluid flows.

[0074] The control and analysis system includes a concentration analyzer (400) that measures the concentration of a reference gas, and a concentration control unit (600) that controls the operation of a heater (321) and a metering pump (500) based on the measured value.

[0075] In addition, the drive system consists of a support coupling part (350) and a cylinder (700) that raises and lowers the liquid storage container (333).

[0076] Here, the metering pump (500) supplies a liquid or gas simulant at an accurate flow rate to ensure precision in controlling the reference gas concentration, and the concentration analyzer (400) measures the concentration of the discharged reference gas in real time and transmits it to the concentration control unit (600).

[0077] In addition, the concentration control unit (600) automatically controls whether the heater (321) is heated and the intensity or the injection amount of the metering pump (500) based on the analyzed value, thereby maintaining the concentration of the reference gas within a constant range.

[0078] In addition, the cylinder (700) raises and lowers the liquid storage container (333) provided inside the inner container (330) of the simulant vaporization unit (300) and the support coupling part (350) supporting the liquid storage container (333) to perform coupling or separation with the simulant vaporization unit (300), and the support coupling part (350) supports the liquid storage container (333) so that it is accurately aligned at the bottom of the simulant vaporization unit (300) when raised, thereby maintaining airtightness.

[0080] As such, each component constituting the present invention described above is designed to be organically combined into a single continuous process, including the flow of the carrier gas, the vaporization and mixing of the simulant, concentration measurement and control, and the opening, closing, and maintenance of the device.

[0081] First, the mass flow meter (100) receives a carrier gas from an external source and precisely controls the flow rate of the carrier gas according to set flow rate conditions. The carrier gas passing through the mass flow meter (100) flows into one side of the hermetic constant temperature chamber (200) along the gas inlet pipe (110) and forms a basic flow of carrier gas inside the hermetic constant temperature chamber (200).

[0082] In addition, the interior of the above-mentioned airtight constant temperature chamber (200) is connected to the upper part of the simulant vaporization unit (300) through a connecting part (220), and in this connected state, a structure is formed in which the flow path inside the airtight constant temperature chamber (200) and the upper space of the simulant vaporization unit (300) are connected.

[0083] Inside the above-mentioned simulant vaporization unit (300), a liquid storage container (333) is placed inside an inner container (330), and the inner container (330) is installed inside an outer container (320).

[0084] The outer container (320) is equipped with a heater (321) to maintain the temperature inside the outer container (320) and the inner container (330) within a certain range, and a bubble generating part (331) is installed at the bottom of the inner container (330) to form bubbles in the liquid simulant inside the liquid storage container (333). The lower end of the negative pressure gas suction pipe (332) is arranged to be connected to the upper space of the inner container (330).

[0085] In addition, the upper end of the above-mentioned negative pressure gas suction pipe (332) is connected to the lower end of the above-mentioned double injection flow path (216).

[0086] The above-mentioned double injection channel (216) is a single channel structure, and as described above, its upper end is connected to the mixing channel (213) inside the airtight constant temperature chamber (200), and its end end is connected to the negative pressure gas suction tube (332) as shown in FIG. 5.

[0087] A liquid injection pipe (217) is arranged coaxially inside the double injection channel (216), and one side of the liquid injection pipe (217) is open inside the double injection channel (216), while the other side is connected to a metering pump (500).

[0088] A small amount of liquid or gaseous simulant supplied from a metering pump (500) is injected into the interior of a double injection channel (216) through a liquid injection pipe (217), and then flows in reverse to the liquid storage container (333) of the storage unit (310) through a negative pressure gas suction pipe (332) in which negative pressure is formed by a negative pressure unit (334). After that, as described above, it is moved to the bubble generation unit (331) to generate bubbles, then moves upward again to be mixed with the gas in the mixing channel (213) through a vaporized gas discharge pipe (215) to adjust the concentration. Finally, the gas with the adjusted concentration is discharged through a reference gas discharge pipe (210).

[0089] In this way, a concentration analyzer (400) is connected to the reference gas discharge pipe (210) to measure the concentration of the discharged reference gas, and a series of feedback processes are repeated in which the measured concentration information is transmitted to the concentration control unit (600), and the process of controlling the gas discharged through the reference gas discharge pipe (210) to reach the concentration of the set standard gas is repeated.

[0090] Based on this information, the concentration control unit (600) controls the heating amount of the heater (321) and the injection amount of the metering pump (500), thereby simultaneously controlling the vaporization conditions inside the simulant vaporization unit (300) and the mixing conditions inside the double injection channel (216).

[0091] In this way, each component provides mutual feedback based on gas flow, temperature, concentration, vaporization, and mixing conditions, and the entire device operates organically combined into a single closed-loop structure.

[0093] As described above, the present invention operates as a cyclic process of a preparation step, a vaporization and mixing step, a concentration measurement and control step, and a termination and re-preparation step.

[0094] First, in the preparation stage, a predetermined amount of liquid simulant selected according to the purpose of the experiment is injected into the liquid storage container (333).

[0095] A liquid storage container (333) provided inside the simulant vaporization unit (300) can be moved upward by the operation of a cylinder (700) as shown in Figure 3 or Figure 4 and can be closely coupled to the lower part of the simulant vaporization unit (300).

[0096] At this time, the support coupling part (350) guides the position of the simulant vaporization part (300) so that it is accurately aligned, thereby stably securing the communication state between the lower side of the liquid storage container (333) and the simulant vaporization part (300), and maintaining airtightness and a negative pressure state by the negative pressure part.

[0097] Once the preparation is complete in this way, the carrier gas supply begins in the mass flow meter (100).

[0098] The carrier gas is controlled to a set flow rate while passing through the mass flow meter (100) and is introduced into the mixing channel (213) inside the airtight constant temperature chamber (200) through the gas inlet pipe (110).

[0099] Inside the above mixing channel (213), the carrier gas flows at a constant flow rate and forms a stable state due to external temperature conditions.

[0100] At the same time, in the simulant vaporization unit (300), the heater (321) operates according to the set concentration condition to raise the temperature of the outer container (320) and the inner container (330).

[0101] The operation of the above-mentioned heater (321) can be operated optionally.

[0102] As the liquid storage container (333) contained in the inner container (330) is also heated, the temperature of the liquid simulant stored therein rises.

[0103] A bubble generating unit (331) is provided at the bottom of the liquid storage container (333) and is structured to be connected to a negative pressure unit (334) and a negative pressure gas suction pipe (332) at the top as described above. A small amount of simulant flowing into the metering pump (500) is guided to the bubble generating unit (331) through the liquid injection pipe (217) provided in a double layer inside the double injection flow path (216) and through the negative pressure gas suction pipe (332) which is in a negative pressure condition, and then generates bubbles.

[0104] In this way, when bubbles are formed inside the liquid storage container (333) by passing through the bubble generating part (331), the surface area of ​​the liquid increases and vaporization proceeds more actively.

[0105] In this process, the simulant accumulates in a gaseous state in the upper space of the inner container (330), that is, the liquid storage container (333).

[0106] The vaporized simulant present in the upper space of the simulant vaporization section (300) flows into the mixing channel (213) through the vaporization gas discharge pipe (215) as shown in the drawing.

[0107] As described above, the gas introduced into the mixing pipe (213) has its concentration controlled and is discharged through the standard gas discharge pipe (210).

[0108] That is, in the present invention, the fluid flow of the vaporized gas is connected to the mixing channel (213) through the gas inlet pipe (110) and to the reference gas discharge pipe (210), and a small amount of simulant from the metering pump (500) is provided through the liquid injection pipe (217) inside the double injection channel (216) under a negative pressure state, then flows backward toward the liquid storage container (333) through the negative pressure gas suction pipe (332), passes through the bubble generation part (331) to form bubbles, rises, is mixed again in the mixing channel (213) through the vaporized gas discharge pipe (215), and then has a bypass path leading to the reference gas discharge pipe (210).

[0109] The above-described metering pump (500) injects a small amount of liquid simulant into the double injection channel (216) through the liquid injection pipe (217) according to the set conditions. Through the above-described series of processes, it acts as a fine adjustment step to more precisely control the final concentration of the reference gas.

[0110] The standard gas discharged in this manner passes through a concentration analyzer (400) connected to the standard gas discharge pipe (210), and its concentration is measured in real time.

[0111] The measurement result of the concentration analyzer (400) is transmitted to the concentration control unit (600), and the concentration control unit (600) automatically controls the heating of the heater (321) and the injection flow rate of the metering pump (500) based on this result.

[0112] For example, if the concentration of the reference gas is measured to be lower than the set value, the concentration control unit (600) controls the output of the heater (321) or the injection amount of the metering pump (500) to increase, and conversely, if the concentration is measured to be higher, controls the heating amount of the heater (321) or the injection amount of the pump to decrease.

[0113] Through such feedback control, the standard gas generator according to the present invention can maintain the concentration of the reference gas within a stable range even if disturbances occur over time.

[0114] Meanwhile, when the operation of the device according to the present invention is terminated or maintenance is required, the cylinder (700) is driven downward to separate the liquid storage container (333) provided inside the simulant vaporization unit (300) from the simulant vaporization unit (300), and thus the replacement of the simulant inside the liquid storage container (333), internal cleaning, and inspection of the bubble generation unit (331) or negative pressure gas suction pipe (332) can be easily performed.

[0115] When operating again thereafter, the reference gas can be regenerated in the same procedure by raising the support coupling part (350) and the liquid storage container (333) according to the operation of the cylinder (700) and closely reconnecting them with the lower part of the simulant vaporization part (300).

[0117] In this way, the standard gas generator of the present invention enables the generation of a stable and highly reproducible reference gas by having each component operate organically around the processes of gas flow, vaporization and mixing, concentration feedback control, and mechanical coupling and separation.

[0119] Although the present invention has been described above based on limited embodiments and drawings, the present invention is not limited to the above embodiments, and those skilled in the art will recognize that various modifications and variations are possible from the description in this specification.

[0120] Accordingly, the technical scope of the present invention should be determined by the following claims, and all equivalent or equivalent variations thereof should be interpreted as being included within the technical scope of the present invention. Explanation of the symbols

[0122] 100; Mass flow meter 110; Gas inlet pipe 200; airtight constant temperature chamber 210; standard gas exhaust pipe 213; Mixing channel 214; Connecting pipe 215; Vaporized gas discharge pipe 216; Double injection flow path pipe 217; Liquid injection pipe 220; Connection part 300; Simulant vaporization unit 310; Storage unit 320; outer container 321; heater 330; Inner container 331; Bubble generating part 332; Negative pressure gas suction tube 333; Liquid storage container 334; negative pressure part 350; support coupling part 400; Concentration analyzer 500; Metering pump 600; Concentration control unit 700; Cylinder 800; support

Claims

Claim 1 A standard gas generating device comprising: a mass flow meter (100) that supplies a carrier gas at a constant flow rate; a gas inlet pipe (110) through which the carrier gas is introduced from one side through the mass flow meter (100) and forms a flow path that is mixed with a vaporized gas inside and then connected to a reference gas discharge pipe (210) on the other side; a simulant vaporization unit (300) that stores, heats, and vaporizes a liquid simulant; and a cylinder (700) that raises and lowers a support coupling unit (350) connected to the lower side of the simulant vaporization unit (300) to connect or disconnect it; wherein a liquid storage container (333) for storing the liquid simulant is provided on the upper surface of the support coupling unit (350), so that the liquid storage container (333) is introduced into or withdrawn from the simulant vaporization unit (300) according to the operation of the cylinder (700). Claim 2 In claim 1, the standard gas generating device comprises a storage unit (310) in which the simulant vaporization unit (300) is composed of an outer container (320), an inner container (330), and a liquid storage container (333). Claim 3 In claim 1, the hermetic constant temperature chamber (200) comprises: a mixing channel (213) connected at one end to the gas inlet pipe (110); a reference gas discharge pipe (210) connected to the other end of the mixing channel (213) to discharge gas to the outside; a vaporization gas discharge pipe (215) connected vertically downward from the part where the gas inlet pipe (110) and the mixing channel (213) are connected; a double injection channel (216) for supplying a small amount of simulant from the outside; a connecting pipe (214) connecting the double injection channel (216) and the mixing channel (213); and a negative pressure gas suction pipe (332) provided in the simulant vaporization section (300) and connected to the end of the double injection channel (216); a standard gas generating device. Claim 4 A standard gas generating device comprising, in claim 3, a liquid injection pipe (217) formed coaxially inside the double injection channel (216). Claim 5 In claim 2, a standard gas generating device comprising: a bubble generating part (331) that forms bubbles in a liquid simulant at the bottom of the liquid storage container (333) of the inner container (330). Claim 6 A standard gas generating device comprising: a connecting part (220) for connecting the simulant vaporization part (300) and the hermetic constant temperature chamber (200) in claim 1. Claim 7 A standard gas generating device according to claim 1, comprising a metering pump (500) connected to one side of the hermetic constant temperature chamber (200) to supply simulant liquid or gas inside. Claim 8 delete Claim 9 A standard gas generating device according to claim 1, comprising: a concentration analyzer (400) connected to the standard gas discharge pipe (210) for analyzing the concentration of the standard gas discharged; and a concentration control unit (600) for controlling a heater (321) or a metering pump (500) according to the analysis value of the concentration analyzer (400).

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