Combined nitrogen making machine and nitrogen making process thereof

Abstract

The invention discloses a combined nitrogen making machine and a nitrogen making process thereof, and relates to the technical field of nitrogen preparation, the combined nitrogen making machine comprises a filter, the filter is internally provided with a filter cavity and a cleaning cavity which are communicated with each other, the filter cavity and the cleaning cavity are internally provided with a filter part capable of rotating in the radial direction, and the filter part comprises a filter screen and a standby screen; the filtering net and the standby net are two metal nets which are arranged at an interval, and an insulating baffle is arranged between the filtering net and the standby net; according to the invention, the filter screen and the standby screen are arranged and can be radially switched, so that the alternate use of the filter pieces is realized, when one screen is used for filtering, the other screen can be cleaned or maintained, the continuous operation of the whole filter system is ensured, the downtime caused by replacement or cleaning of the filter pieces is reduced, the production efficiency is improved, and the production cost is reduced. And economic loss caused by shutdown is reduced, and the device is suitable for the industrial fields with high continuity, such as chemical production.

Description

Technical Field

[0001] The invention relates to the technical field of nitrogen preparation, and in particular to a combined nitrogen making machine and a nitrogen making process thereof. Background Art

[0002] In industrial production, nitrogen is widely used in fields such as chemical synthesis, electronic manufacturing, and food preservation. There are strict requirements on the purity and supply stability of nitrogen. Traditional nitrogen generators face many challenges and shortcomings during operation.

[0003] In the air pretreatment stage, early air filtration technology was relatively simple, mostly using simple mechanical filtration methods, such as single-layer fiber filters or metal filters.

[0004] These filters only rely on the principle of physical blocking to remove impurities. They have limited filtering effects on tiny particles, such as dust, pollen, microorganisms, and organic and inorganic aerosols with particle sizes in the micrometer or even nanometer range. Tiny particles can easily penetrate the filter and enter the nitrogen generator, causing contamination of the nitrogen generator adsorbent.

[0005] For example, in the electronic chip manufacturing process, even a very small amount of impurity particles entering the nitrogen supply system may be deposited on the chip surface, affecting the chip's performance and yield.

[0006] Although some improved filtering methods have emerged as technology has developed, problems still exist.

[0007] For example, although some electrostatic adsorption filters utilize electrostatic fields to improve the ability to capture tiny particles, they face difficulties in regenerating and maintaining the filter elements.

[0008] When the filter element is saturated with adsorption, it needs to be shut down and manually disassembled for cleaning or replacement. This not only causes the nitrogen production process to be interrupted and affects production efficiency, but also the frequent disassembly and installation operations increase the risk of equipment damage and labor costs.

[0009] In view of this, this application is hereby filed. Summary of the invention

[0010] The object of the present invention is to provide a combined nitrogen generator to solve the problems raised in the above background technology.

[0011] Another object of the present invention is to provide a nitrogen production process.

[0012] In order to solve the above technical problems, the present invention provides a combined nitrogen generator, including a filter, wherein the filter is provided with a filter chamber and a cleaning chamber that are interconnected, and a filter element is radially rotatably provided in the filter chamber and the cleaning chamber, and the filter element includes a filter screen and a spare screen, and the filter screen and the spare screen are both two metal screens arranged at intervals, and an insulating baffle is arranged between the filter screen and the spare screen, and a telescopic contact is arranged in the filter chamber, and the telescopic contact is divided into two contacts, a positive electrode and a negative electrode, which are respectively connected to the positive and negative electrodes of a power supply.

[0013] Furthermore, the outer sides of the filter screen and the spare screen are wrapped with an insulating ring, and the insulating ring is provided with a connecting port, and the connecting ports have two connected ports distributed at equal intervals in a circular array.

[0014] Furthermore, a through hole is formed on the top surface of the cleaning chamber, a plasma nozzle is inserted into the through hole, and a plurality of the plasma nozzles are spaced apart and distributed in a linear array.

[0015] Furthermore, a fan is arranged on the back of the cleaning chamber, and two of the fans are spaced apart in a linear array, and the top of the fan frame is inclined toward the front side of the filter.

[0016] Furthermore, an ash discharge port is provided in the cleaning chamber, and the ash discharge port is located at the bottom surface of the cleaning chamber, an inner wall of the ash discharge port is parallel to the inner wall of the cleaning chamber, and the interior of the ash discharge port is connected with the cleaning chamber.

[0017] Furthermore, a mounting plate is provided on the back of the filter, a motor is mounted on the mounting plate, an output shaft of the motor is connected to a connecting shaft, and the connecting shaft is fixedly connected to the center of the filter element.

[0018] Furthermore, a trigger rod is arranged on the connecting shaft, and a delay switch electrically connected to the plasma nozzle and the blower is arranged on the back of the filter, and the delay switch is located within the rotation radius of the trigger rod.

[0019] Furthermore, a harmonic reducer is arranged between the motor and the connecting shaft.

[0020] A nitrogen production process, applied to any of the above-mentioned combined nitrogen generators, specifically comprising the following steps: S1. The air first enters the air compressor, which compresses the air through the motor driving the piston or impeller and other components to increase the air pressure; S2. The compressed air enters the air buffer tank. The function of the air buffer tank is to stabilize the air pressure and reduce pressure fluctuations. S3, the air coming out of the air buffer tank enters the freeze dryer; S4. Freeze dryer uses refrigeration system to cool air to below dew point temperature, condenses water vapor in the air into liquid water or solid ice, and then removes the water through gas-liquid separator or drainage device; S5. The freeze-dried air passes through a filter, which further filters the impurity particles remaining in the air, such as dust, oil mist, etc.; S6, the filtered air enters the nitrogen generator; The nitrogen generator achieves adsorption and regeneration of the adsorbent by periodically changing the pressure, thereby continuously producing nitrogen; The nitrogen produced by the nitrogen generator enters the nitrogen buffer tank.

[0021] Compared with the prior art, the present invention has the following beneficial effects: In the present invention, a filter screen and a spare screen are provided and can be switched radially, so that the alternating use of filter elements can be realized. When one screen is filtering, the other screen can be cleaned or prepared for maintenance, thereby ensuring the continuous operation of the entire filtration system, reducing the downtime caused by replacing or cleaning the filter elements, improving production efficiency, and reducing the economic losses caused by downtime. The present invention is suitable for industrial fields with strong continuity such as chemical production.

[0022] In the present invention, the electrostatic field between the metal meshes is used to filter the air, which can effectively capture tiny particles in the air, including dust, pollen, microorganisms, etc. Compared with the traditional simple mechanical filtration method, the filtration efficiency is higher, and the degree of air purification can be significantly improved, providing purer air raw materials for subsequent nitrogen production processes, etc., which helps to improve the performance and product quality of the entire nitrogen generator system.

[0023] In the present invention, through the coordination of the motor, the connecting shaft, the trigger rod and the delay switch, and the precise power transmission of the harmonic reducer, precise automatic control of the filter element switching and the cleaning process is achieved, and the filtering and cleaning operations can be performed according to the set procedures without human intervention, thereby improving the intelligence level and operational reliability of the equipment, reducing the risks caused by human operational errors, ensuring the stable operation of the entire nitrogen generator system, reducing the equipment failure rate, and increasing the overall service life of the equipment. The invention is suitable for various industrial production environments with high requirements on equipment stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A front view of a filter of a combined nitrogen generator; Figure 2 A rear view of a filter of a combined nitrogen generator; Figure 3 It is a schematic diagram of the internal structure of a filter of a combined nitrogen generator; Figure 4 for Figure 3The enlarged view of point A in the middle; Figure 5 It is a schematic diagram of the cross-sectional structure of a filter of a combined nitrogen generator; Figure 6 It is a schematic diagram of the filter structure of a combined nitrogen generator; Figure 7 The present invention is a schematic diagram of the trigger rod and delay switch structure of a combined nitrogen generator.

[0025] In the figure: 1. filter; 101. filter chamber; 102. cleaning chamber; 103. mounting plate; 2. filter element; 201. filter screen; 202. spare screen; 203. insulating ring; 204. insulating baffle; 205. connection port; 206. telescopic contact; 3. plasma nozzle; 301. fan; 302. ash outlet; 303. delay switch; 4. motor; 401. connecting shaft; 402. trigger rod; 5. gas pipeline. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0027] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0028] See also Figure 1-7 , the present invention provides a technical solution: A modular nitrogen generator comprises an air compressor, an air buffer tank, a freeze dryer, a nitrogen generator host, a nitrogen buffer tank, and a filter 1 arranged between the freeze dryer and the nitrogen generator host, and gas pipelines 5 are arranged on both sides of 1.

[0029] The filter 1 is provided with a filter chamber 101 and a cleaning chamber 102 which are interconnected. A filter element 2 is radially rotatably provided in the filter chamber 101 and the cleaning chamber 102. The filter element 2 includes a filter screen 201 and a spare screen 202. The filter screen 201 and the spare screen 202 are two metal screens arranged at intervals. An insulating baffle 204 is arranged between the filter screen 201 and the spare screen 202. A telescopic contact 206 is arranged in the filter chamber 101. The telescopic contact 206 is divided into two contacts, a positive pole and a negative pole, which are respectively connected to the positive and negative poles of the power supply.

[0030] The outside of the filter net 201 and the spare net 202 are wrapped with an insulating ring 203, and a connecting port 205 is opened on the insulating ring 203. There are two connecting ports 205 distributed in a circular array with equal intervals.

[0031] Air enters the filter cavity 101 from the inlet of the filter 1 , and when the filter element 2 is in the initial filtering position, the air first contacts the filter screen 201 .

[0032] Since the filter screen 201 is composed of metal screens arranged at intervals, and there are telescopic contacts 206 in the filter cavity 101 that are respectively connected to the two poles of the metal screens with a power source, an electrostatic field is formed between the metal screens.

[0033] When air flows through the metal mesh, tiny particles in the air are adsorbed onto the metal mesh under the action of the electrostatic field, thereby achieving preliminary purification of the air.

[0034] The insulating baffle 204 separates the filter screen 201 and the backup screen 202 to prevent problems such as electrical short circuits between the two and ensure the normal formation and function of the electrostatic field.

[0035] The insulating ring 203 is wrapped around the outside of the metal mesh to provide insulation protection, and the connecting port 205 is used to contact the filter mesh 201 and the spare mesh 202 at the telescopic contact 206 to make them electrically charged.

[0036] After the filter 201 has been used for a period of time, the impurities adsorbed on the surface of the filter 201 gradually increase, and the filtering efficiency decreases.

[0037] At this time, the filter element 2 is rotated radially by an external drive device.

[0038] During the rotation, the filter net 201 gradually leaves the filter chamber 101 and enters the cleaning chamber 102, while the spare net 202 originally in the cleaning chamber 102 rotates to the position of the filter chamber 101 and starts to take on the filtering task.

[0039] After the switching process is completed, the telescopic contact 206 will contact the backup net 202 and energize it to form an electrostatic field, ensuring the continuity and stability of the filtering work.

[0040] Using the electrostatic field between metal meshes to filter the air can effectively capture tiny particles in the air, including dust, pollen, microorganisms, etc. Compared with traditional pure mechanical filtration methods, the filtration efficiency is higher and the degree of air purification can be significantly improved. It can provide purer air raw materials for subsequent nitrogen production processes, which helps to improve the performance and product quality of the entire nitrogen generator system.

[0041] The filter net 201 and the spare net 202 are provided and can be radially switched, so that the filter element 2 can be used alternately.

[0042] When one net is filtering, the other net can be cleaned or prepared for maintenance, ensuring the continuous operation of the entire filtering system and reducing the downtime caused by replacing or cleaning the filter element 2.

[0043] Moreover, a variety of cleaning methods can be conveniently adopted in the cleaning chamber 102 to clean the used filter screen 201, thereby extending the service life of the filter element 2 and reducing the operating cost.

[0044] The provision of the insulating baffle 204 and the insulating ring 203 improves the electrical safety of the filter element 2 .

[0045] The insulating baffle 204 prevents short circuits between the metal meshes, thereby ensuring stable formation and normal operation of the electrostatic field.

[0046] The insulating ring 203 provides all-round insulation protection for the metal mesh, avoiding electrical failures caused by accidental contact between the metal mesh and external metal parts, improving the stability and reliability of the entire filter structure, and reducing equipment failures and safety hazards caused by electrical problems.

[0047] Furthermore, a through hole is formed on the top surface of the cleaning chamber 102, and a plasma nozzle 3 is inserted into the through hole. There are a plurality of plasma nozzles 3 distributed at intervals in a linear array.

[0048] A fan 301 is disposed on the back of the cleaning chamber 102 . Two fans 301 are spaced apart in a linear array, and the top of the fan 301 frame is inclined toward the front side of the filter 1 .

[0049] An ash lowering opening 302 is provided in the cleaning chamber 102 . The ash lowering opening 302 is located at the bottom surface of the cleaning chamber 102 , and its inner wall is parallel to the inner wall of the cleaning chamber 102 , and its interior is communicated with the cleaning chamber 102 .

[0050] When the filter element 2 (such as the filter screen 201 or the spare screen 202 ) needs to be cleaned, the filter element 2 is rotated to the cleaning chamber 102 position.

[0051] At this time, a plurality of plasma nozzles 3 distributed in a linear array and spaced apart in the through holes on the top surface of the cleaning chamber 102 start to work, spraying plasma into the cleaning chamber 102 .

[0052] The plasma is rich in various active particles (such as ions, free radicals, etc.), and these active particles chemically react with the impurity particles adsorbed on the filter element 2.

[0053] For example, for some organic impurities, the oxygen free radicals in the plasma can react with them, oxidizing and decomposing them into small molecular gases or substances that are easier to remove; for metal oxide impurities, the ions in the plasma may undergo replacement or reduction reactions with them, changing their chemical structure and physical attachment state, causing them to detach from the surface of the filter element 2 or become loose so that they can be removed later.

[0054] While the plasma nozzle 3 is working, two fans 301 spaced apart in a linear array on the back of the cleaning chamber 102 are started.

[0055] The fan 301 generates an airflow, and because the top of the fan 301 frame is inclined toward the front side of the filter 1 , the airflow forms a specific flow direction in the cleaning chamber 102 .

[0056] On the one hand, the airflow helps to carry the gaseous products generated by the reaction of plasma and impurities out of the cleaning chamber 102; on the other hand, for those solid impurity particles that have fallen off the surface of the filter element 2 after plasma treatment but still remain in the cleaning chamber 102, the airflow gives them an outward force, causing them to move along the inner wall of the cleaning chamber 102 toward the bottom surface.

[0057] The ash outlet 302 is arranged on the bottom surface of the cleaning chamber 102, and its inner wall is parallel to the inner wall of the cleaning chamber 102. Under the guidance of the airflow of the fan 301, the solid impurity particles are finally discharged from the cleaning chamber 102 through the ash outlet 302, completing the cleaning process of the filter element 2, so that the filter element 2 can be put into use again after cleaning, ensuring the continuous and efficient operation of the filter.

[0058] The plasma nozzle 3 utilizes the high activity of plasma to effectively decompose and remove various types of stubborn impurities on the filter element 2, and can achieve better treatment effects regardless of whether they are organic pollutants, metal oxides or other complex chemical combinations.

[0059] The auxiliary function of the fan 301 further enhances the cleaning effect, and the reaction products and detached impurities are promptly taken away by the airflow, avoiding the problem of secondary pollution and re-adsorption of impurities on the filter element 2, greatly improving the cleaning efficiency and quality, and extending the service life of the filter element 2.

[0060] The perforations on the top surface facilitate the installation and layout of the plasma nozzle 3, and enable the plasma to evenly cover the filter element 2 in the cleaning chamber 102, thereby ensuring comprehensive cleaning.

[0061] The top of the fan 301 frame is inclined toward the front side of the filter 1. This design is conducive to guiding the airflow to blow the impurities cleaned by plasma out of the filter 1 from the ash outlet 302 at the bottom of the cleaning chamber 102, thereby completing the cleaning process of the filter element 2.

[0062] The position and structural design of the ash outlet 302 facilitate the collection and discharge of impurities, prevent the impurities from accumulating in the cleaning chamber 102, maintain the clean environment of the cleaning chamber 102, and facilitate the continuous and stable progress of the entire cleaning process.

[0063] The design of the cleaning chamber 102 is adapted to the automated operation mode of the entire filter and nitrogen generator system.

[0064] For example, when the filter element 2 is switched to the cleaning chamber 102, the plasma nozzle 3 and the fan 301 can automatically start and stop according to the preset program without excessive human intervention, thereby improving the intelligence level and operational reliability of the equipment, reducing the risks caused by human operational errors, and ensuring the stable operation of the nitrogen generator system.

[0065] Furthermore, a mounting plate 103 is provided on the back of the filter 1 , and a motor 4 is mounted on the mounting plate 103 . The output shaft of the motor 4 is connected to a connecting shaft 401 , and the connecting shaft 401 is fixedly connected to the center of the filter element 2 .

[0066] A trigger rod 402 is disposed on the connecting shaft 401 , and a delay switch 303 electrically connected to the plasma nozzle 3 and the fan 301 is disposed on the back of the filter 1 . The delay switch 303 is located within the rotation radius of the trigger rod 402 .

[0067] A harmonic reducer is arranged between the motor 4 and the connecting shaft 401 .

[0068] The motor 4 drives the connecting shaft 401 to rotate through the harmonic reducer, and the connecting shaft 401 is fixedly connected to the filter element 2, so as to realize the radial rotation switching of the filter element 2 between the filter cavity 101 and the cleaning cavity 102.

[0069] When the filter element 2 rotates to a certain angle, the trigger rod 402 on the connecting shaft 401 rotates accordingly. When the trigger rod 402 enters the sensing area of ​​the delay switch 303 (within its rotation radius), the trigger rod 402 triggers the delay switch 303 .

[0070] After the delay switch 303 is triggered, the plasma nozzle 3 on the top surface of the cleaning chamber 102 is first started, and the plasma nozzle 3 sprays plasma into the cleaning chamber 102 to clean the filter element 2 in the cleaning chamber 102 (at this time, the used filter screen 201 or the spare screen 202 just switched from the filter chamber 101).

[0071] The active particles in the plasma react chemically with the impurities adsorbed on the filter 201, decomposing the impurities or changing their physical and chemical properties, making them easier to remove later.

[0072] At the same time, the delay switch 303 also starts the fan 301 at the back of the cleaning chamber 102, and the fan 301 generates airflow.

[0073] The delay time set by the delay switch 303 can ensure that the plasma nozzle 3 has enough time to fully clean the filter element 2, and after cleaning, the motor 4 can continue to rotate to switch the cleaned filter element 2 back to the filter chamber 101 or allow the spare net 202 to enter the filter chamber 101 to start a new round of filtering work.

[0074] Through the cooperation of the motor 4, the connecting shaft 401, the trigger rod 402 and the delay switch 303, accurate automatic control of the switching and cleaning process of the filter element 2 is achieved.

[0075] Filtration and cleaning operations can be performed according to the set procedures without human intervention, which improves the intelligence and operational reliability of the equipment, reduces the risks caused by human operational errors, and ensures the stable operation of the entire nitrogen generator system.

[0076] By utilizing the coordinated work of the plasma nozzle 3 and the fan 301 , the filter element 2 can be cleaned efficiently.

[0077] The chemical reaction activity of plasma can effectively remove the impurities stubbornly adsorbed on the filter 201. The fan 301 blows out the cleaned impurities in time to prevent them from being adsorbed again or accumulated in the filter 1, thereby ensuring the regeneration effect of the filter element 2, extending the service life of the filter element 2, and reducing the replacement frequency and cost of the filter element 2.

[0078] The harmonic reducer arranged between the motor 4 and the connecting shaft 401 has the advantages of high precision, high torque, low backlash, etc.

[0079] It can accurately transmit the power of the motor 4 to the connecting shaft 401, ensure the smoothness and accuracy of the rotation of the filter element 2, reduce the problems of the filter element 2 not switching into place or being damaged due to unstable power transmission, and improve the operation stability and durability of the entire filter 1 and even the nitrogen generator system.

[0080] See also Figure 1 - Figure 7 The present invention also provides a process: The air first enters the air compressor, which compresses the air through an electric motor driving the piston or impeller and other components to increase the air pressure.

[0081] The compressed air enters the air buffer tank. The function of the air buffer tank is to stabilize the air pressure and reduce pressure fluctuations.

[0082] Because the output pressure of the air compressor may fluctuate during operation, and stable pressure is crucial for the subsequent freeze drying and nitrogen production processes.

[0083] The air from the air buffer tank enters the freeze dryer.

[0084] The freeze dryer uses a refrigeration system to cool the air to below the dew point temperature, condensing the water vapor in the air into liquid water or solid ice, and then removes the moisture through a gas-liquid separator or a drainage device.

[0085] This can reduce the air humidity and prevent moisture from freezing in the nitrogen generator or affecting the performance of the nitrogen adsorbent during the subsequent nitrogen production process, thereby ensuring the normal progress of the nitrogen production process.

[0086] The freeze-dried air passes through the filter 1, and the filter 1 further filters the impurity particles remaining in the air, such as dust, oil mist, etc.

[0087] The filtered air enters the nitrogen generator.

[0088] The nitrogen generator usually adopts nitrogen production technology such as pressure swing adsorption (PSA) or membrane separation.

[0089] Taking PSA technology as an example, the nitrogen generator is equipped with adsorbent. Under a certain pressure, impurities such as oxygen and carbon dioxide in the air are adsorbed by the adsorbent, and nitrogen is separated as product gas.

[0090] The nitrogen generator achieves adsorption and regeneration of the adsorbent by periodically changing the pressure, thereby continuously producing nitrogen.

[0091] The nitrogen produced by the nitrogen generator enters the nitrogen buffer tank. The function of the nitrogen buffer tank is similar to that of the air buffer tank, which is mainly to stabilize the nitrogen pressure and reduce pressure fluctuations so that the output nitrogen pressure can meet the user's requirements.

Claims

1. A combined nitrogen generator, characterized in that: The invention comprises a filter (1), wherein the filter (1) is provided with a filter chamber (101) and a cleaning chamber (102) which are interconnected, wherein a filter element (2) is radially rotatably provided in the filter chamber (101) and the cleaning chamber (102), wherein the filter element (2) comprises a filter screen (201) and a spare screen (202), wherein the filter screen (201) and the spare screen (202) are two metal screens arranged at intervals, wherein an insulating baffle (204) is arranged between the filter screen (201) and the spare screen (202), and wherein a telescopic contact (206) is arranged in the filter chamber (101), wherein the telescopic contact (206) is divided into two contacts, namely a positive electrode and a negative electrode, which are respectively connected to the positive and negative electrodes of a power source.

2. A combined nitrogen generator according to claim 1, characterized in that: The outsides of the filter screen (201) and the spare screen (202) are wrapped with an insulating ring (203), and a connecting port (205) is provided on the insulating ring (203). The connecting ports (205) have two equidistantly spaced connections in a circular array.

3. A combined nitrogen generator as claimed in claim 2, characterized in that: The top surface of the cleaning chamber (102) is provided with a through hole, a plasma nozzle (3) is inserted into the through hole, and a plurality of the plasma nozzles (3) are spaced apart and arranged in a linear array.

4. A combined nitrogen generator as claimed in claim 3, characterized in that: A fan (301) is arranged on the back of the cleaning chamber (102), and two of the fans (301) are spaced apart in a linear array, with the top of the fan (301) frame tilted toward the front side of the filter (1).

5. A combined nitrogen generator as claimed in claim 4, characterized in that: An ash lowering opening (302) is provided in the cleaning chamber (102); the ash lowering opening (302) is located on the bottom surface of the cleaning chamber (102), its inner wall is parallel to the inner wall of the cleaning chamber (102), and its interior is connected to the cleaning chamber (102).

6. A combined nitrogen generator as claimed in claim 5, characterized in that: A mounting plate (103) is provided on the back of the filter (1), a motor (4) is mounted on the mounting plate (103), an output shaft of the motor (4) is connected to a connecting shaft (401), and the connecting shaft (401) is fixedly connected to the center of the filter element (2).

7. A combined nitrogen generator according to claim 6, characterized in that: A trigger rod (402) is provided on the connecting shaft (401), and a delay switch (303) electrically connected to the plasma nozzle (3) and the fan (301) is provided on the back of the filter (1), wherein the delay switch (303) is located within the rotation radius of the trigger rod (402).

8. A combined nitrogen generator according to claim 7, characterized in that: A harmonic reducer is provided between the motor (4) and the connecting shaft (401).

9. A nitrogen production process, characterized in that: Applied to the combined nitrogen generator described in any one of claims 1 to 8 above, the specific steps include: S1. The air first enters the air compressor, which compresses the air through the motor driving the piston or impeller and other components to increase the air pressure; S2. The compressed air enters the air buffer tank. The function of the air buffer tank is to stabilize the air pressure and reduce pressure fluctuations. S3, the air coming out of the air buffer tank enters the freeze dryer; S4. Freeze dryer uses refrigeration system to cool air to below dew point temperature, condenses water vapor in the air into liquid water or solid ice, and then removes the water through gas-liquid separator or drainage device; S5, the freeze-dried air passes through the filter (1), and the filter (1) further filters the impurity particles remaining in the air, such as dust, oil mist, etc.; S6, the filtered air enters the nitrogen generator; The nitrogen generator achieves adsorption and regeneration of the adsorbent by periodically changing the pressure, thereby continuously producing nitrogen; The nitrogen produced by the nitrogen generator enters the nitrogen buffer tank.

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