Gas booster pump driven by lead screw motor

Abstract

The utility model discloses a gas booster pump driven by a lead screw motor, which relates to the technical field of gas compression and comprises a booster pump body formed by connecting a gas pressure cylinder part and a lead screw motor driving part. The gas pressure cylinder part comprises a compression cavity which is provided with a gas inlet, a gas outlet and a one-way valve, and a piston is arranged in the cavity; and a screw rod motor shaft capable of stretching and retracting in a reciprocating manner is arranged in the screw rod motor driving part and is fixedly or floatingly connected with the piston. A stator and a rotor nut are coaxially sleeved in the lead screw motor shell, and a lead screw motor shaft is provided with an anti-rotation structure. During working, the rotor nut rotates to drive the lead screw motor shaft to move to push the piston to compress gas. The air compressor has the beneficial effects that the screw rod motor is used for driving the booster pump to work, the noise is low during air boosting work, and the efficient and accurate air compression requirement is met.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of gas compression relates to a screw rod motor drive's gas booster pump. BACKGROUND

[0002] In the technical field of gas compression, the traditional compressor design is mostly dependent on rotary or reciprocating piston structure. These structures convert the rotary power of the motor into linear reciprocating motion of the piston through a series of complex mechanical transmission devices such as crankshafts and connecting rods, and then achieve the purpose of gas compression. However, the inherent limitations of such traditional design cannot be ignored: there are many mechanical transmission components, the overall structure is complex, the maintenance cost is high, and the energy loss in the conversion process is large, resulting in low conversion efficiency.

[0003] With the continuous progress and innovation of screw rod motor technology, its high speed, high precision and high reliability characteristics have attracted increasing attention in the industry. Screw rod motor can directly convert electrical energy into linear motion efficiently, eliminating the intermediate transmission mechanism in traditional design. This feature greatly simplifies the mechanical structure, reduces the complexity of the system, and significantly improves the efficiency of energy conversion. In view of this, introducing screw rod motor technology into the field of gas compression and exploring its innovative application in this field has become a highly potential research direction. Through this change, it is expected to overcome the shortcomings of traditional compressor design and promote the development of gas compression technology to be more efficient, more reliable and more economical. SUMMARY

[0004] The utility model discloses a screw rod motor driven gas booster pump, which uses a screw rod motor to drive the booster pump to work. The gas booster pump has low noise during gas compression and meets the requirements of efficient and accurate gas compression.

[0005] To achieve the above purpose, the utility model adopts the following technical scheme: a screw rod motor driven gas booster pump, comprising a booster pump body, the booster pump body comprises a gas booster cylinder part and a screw rod motor driving part connected, the gas booster cylinder part comprises a compression cavity, the gas booster cylinder part is provided with an air inlet and an air outlet connected with the compression cavity, the air inlet and the air outlet are provided with a check valve, the compression cavity is movably provided with a piston, the screw rod motor driving part is provided with a screw rod motor shaft capable of reciprocating, and the driving end of the screw rod motor shaft extends into the compression cavity and is fixedly connected or floatingly connected with the piston.

[0006] The screw rod motor driving part further comprises a screw rod motor shell, the screw rod motor shaft is arranged in the screw rod motor shell along the axial direction of the gas pressurizing cylinder part, the screw rod motor shell is coaxially sleeved from the outside to the inside and is provided with a stator and a rotor nut, the inner wall of the rotor nut is provided with a nut part matched with the screw rod motor shaft, the screw rod motor shaft is provided with an anti-rotation structure, under the action of the stator, the rotor nut rotates, when the rotor nut rotates, due to the inclined action of the nut part, the rotor nut generates a thrust along the axial direction of the screw rod motor shaft, so as to drive the screw rod motor shaft to move along the axial direction of the gas pressurizing cylinder part, and the screw rod motor shaft drives the piston to reciprocate to realize the compression of the gas.

[0007] In order to further optimize the utility model, the following technical solutions can be preferentially selected:

[0008] Preferably, the anti-rotation mechanism comprises a guide key groove arranged on the screw rod motor shaft, and a guide key matched with the key groove is arranged in the compression cavity and close to the end position.

[0009] Preferably, the gas pressurizing cylinder part and the screw rod motor shell are coaxially and integrally connected.

[0010] Preferably, the outer part of the gas pressurizing cylinder part is provided with a spiral cooling water jacket, the spiral cooling water jacket is provided with a water inlet and a water outlet, and cooling water flows in the spiral cooling water jacket.

[0011] Preferably, the stator is any one of a distributed winding stator, a concentrated winding stator, an inductor type stator and a permanent magnet stator, the rotor nut is a combination of a rotor and a screw rod nut, and the rotor is one of a squirrel cage rotor, a salient pole cage rotor, a semi-hard magnetic steel rotor, a soft steel rotor, a salient pole silicon steel rotor, a micro tooth rack soft steel rotor, a permanent magnet rotor, an inductor type rotor, a coil type rotor and a commutator type rotor.

[0012] Preferably, the screw rod motor shaft adopts one of a trapezoidal screw rod shaft, a planetary roller screw rod shaft and a ball screw rod shaft.

[0013] Preferably, the screw rod motor driving part selects a high-torque low-speed servo motor.

[0014] Preferably, the screw rod motor driving part corresponds to a gas pressurizing cylinder part with one group or two symmetrically arranged groups, and the gas pressurizing cylinder part is compressed on one side or on both sides.

[0015] The utility model has the advantages of

[0016] The gas pressurizing pump driven by the screw rod motor has various innovative designs and can bring remarkable beneficial effects in practical application, and the specific effects are as follows:

[0017] (1) pressurizing structure design

[0018] The combination design of the gas boosting cylinder part and the screw motor driving part is very reasonable. The connection mode (fixed connection or floating connection) of the screw motor shaft and the piston can efficiently transmit the power of the screw motor to the piston, push it to reciprocate in the compression chamber, and the one-way valves on the gas inlet and outlet can ensure the gas to flow in the predetermined direction and avoid backflow, thereby realizing efficient and stable gas boosting. As the driving core, the screw motor driving part is carefully configured with the screw motor shaft along the axial direction of the gas boosting cylinder part. The screw motor body integrates the stator, the rotor nut, and the screw motor shaft, etc. The inner wall of the rotor nut is provided with a nut part matched with the screw motor shaft. This design ensures the accurate transmission of driving force. One end of the screw motor shaft extends into the compression chamber of the gas boosting cylinder part and is connected with the piston through fixed connection or floating connection, thereby realizing the reciprocating motion of the piston and completing the compression process of the gas.

[0019] (2) The coaxial and integrated connection design of the gas boosting cylinder part and the screw motor housing not only makes the overall structure of the booster pump more compact, reduces the occupied space, but also enhances the stability and rigidity of the structure, which helps to reduce vibration and noise during operation, improve the reliability and service life of the booster pump.

[0020] (3) Screw anti-rotation mechanism

[0021] The anti-rotation mechanism on the screw motor shaft, such as the cooperation of the guide key groove and the guide key, can effectively prevent the screw motor shaft from rotating and ensure that it can only move linearly along the axial direction. This makes the movement of the piston more accurate and controllable, improves the precision and efficiency of gas compression, and also reduces wear and failure caused by the rotation of the screw motor shaft.

[0022] (4) Cooling system

[0023] The spiral cooling water jacket arranged outside the gas boosting cylinder part can effectively remove the heat generated during the gas compression process. The cooling water flows in the spiral cooling water jacket, increasing the cooling area and time and improving the heat dissipation efficiency. This helps to reduce the working temperature of the booster pump, prevent damage and performance degradation of parts caused by overheating, and ensure the stability and reliability of the booster pump during long-term operation.

[0024] (5) Motor and screw selection

[0025] There are multiple types of stators and rotor nuts to choose from, and there are also multiple types of screw motor shafts. Meanwhile, the screw motor driving part can be selected with a high-torque low-speed servo motor. This diversified selection can flexibly configure the performance of the booster pump according to different application scenarios and working conditions, meet various complex gas boosting requirements, and improve the versatility and adaptability of the booster pump.

[0026] In summary, compared with traditional compressors, the screw rod motor driven reciprocating gas compressor has significant advantages in many aspects: first, its precise control capability makes the compression process more stable, and the compression efficiency and purity of the gas are significantly improved, achieving super-purification compression; second, the noise generated during the operation of the screw rod motor is extremely low, achieving super-silent compression and providing a more comfortable use environment for users; in addition, due to the compact and stable structure of the screw rod motor driving part, the vibration amplitude of the compressor is extremely small, further prolonging the service life of the equipment.

[0027] At the same time, the compressor also adopts a modular assembly design idea, so that each system can be independently operated and maintained, not only improving the maintainability of the equipment, but also providing users with more gas selection space. By simply adding or replacing modules, it is easy to adjust and optimize the gas volume, meeting the diversified needs of different users for gas compression volume. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a schematic diagram of the internal structure of the gas booster pump;

[0029] Figure 2 is a schematic diagram of the internal structure of the screw rod motor driving part in Example 1;

[0030] Figure 3 is a schematic diagram of the internal structure of the screw rod motor driving part in Example 1;

[0031] Figure 4 is a schematic diagram of the structure of the single booster cylinder part in Example 1;

[0032] Figure 5 is a schematic diagram of the structure of the first type of screw rod motor shaft in Example 1;

[0033] Figure 6 is a schematic diagram of the internal structure of the first type of screw rod motor shaft in Example 1;

[0034] Figure 7 is a schematic diagram of the structure of the second type of screw rod motor shaft in Example 1;

[0035] Figure 8 is a schematic diagram of the internal structure of the second type of screw rod motor shaft in Example 1;

[0036] Figure 9 is a schematic diagram of the structure of the third type of screw rod motor shaft in Example 1;

[0037] Figure 10 is a schematic diagram of the internal structure of the third type of screw rod motor shaft in Example 1;

[0038] Figure 11 Figure 2 is a schematic diagram of the connection of the double-boost cylinder part in Example 2.

[0039] 1-gas boost cylinder part; 2-screw motor driving part; 3-piston; 4-compression cavity; 5-air inlet; 6-air outlet; 7-screw motor shell; 8-stator; 9-rotor nut; 10-screw motor shaft; 11-spiral cooling water jacket; 12-water inlet; 13-water outlet; 14-threaded roller. DETAILED DESCRIPTION

[0040] In the description of the present application, it should be further explained that, unless otherwise explicitly specified and limited, the terms "arrangement", "installation", "connection" and "link" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or the communication between two elements. For ordinary skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0041] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary skilled in the art without creative labor are within the scope of protection of the present application.

[0042] Example 1

[0043] As Figures 1-4As shown, a kind of screw motor driven gas booster pump, including booster pump pump body, booster pump pump body includes the gas booster cylinder portion 1 and screw motor driving portion 2 connected, gas booster cylinder portion includes compression cavity 4, gas booster cylinder portion is set up with the gas inlet 5 of compression cavity 4 connection, gas outlet 6, gas inlet 5, gas outlet 6 are equipped with check valve, piston is movably installed in compression cavity, screw motor driving portion is equipped with the screw motor shaft that can reciprocatingly stretch out and retract, the driving end of screw motor shaft extends to compression cavity and is fixedly connected or floatingly connected piston 3;Wherein screw motor driving portion further includes screw motor shell 7, screw motor shaft 10, screw motor shaft 10 is arranged in screw motor shell along the axial direction of gas booster cylinder portion, stator 8, rotor nut 9 are coaxially sleeved and installed in screw motor shell from outside to inside, nut portion is installed on the inner wall of rotor nut 9 and is matched with screw motor shaft, screw motor shaft is equipped with anti-rotation structure, under the action of stator, rotor nut rotates, when rotor nut rotates, due to the oblique effect of nut portion, rotor nut will generate thrust along the axial direction of screw motor shaft, to drive screw motor shaft to move transversely along the axial direction of gas booster cylinder portion, screw motor shaft pushes or pulls piston to reciprocate and realizes the compression of gas.

[0044] Wherein anti-rotation mechanism includes guide key groove installed on screw motor shaft, guide key matched with key groove is installed in compression cavity near end position, prevent screw motor shaft from rotating, as alternative, spline connection can also be used, spline connection can deliver larger torque, and can ensure that screw motor shaft moves accurately.Process outer spline on screw motor shaft, process inner spline hole in gas booster cylinder portion or screw motor shell, let them cooperate with each other;Or guide pin is installed on the end or side of screw motor shaft, and guide groove is processed on gas booster cylinder portion or screw motor shell, guide pin slides in guide groove, to limit the rotation of screw motor shaft, to not interfere with the movement of piston, while making screw motor shaft shorter as a whole.

[0045] As preferred embodiment, gas booster cylinder portion 1, screw motor shell 7 are coaxially connected, so that the overall structure of booster pump is compact, reduces the occupied space, is convenient for installation and integration into various systems.

[0046] As preferred embodiment, the outer portion of gas booster cylinder portion 1 is sleeved with spiral cooling water jacket 11, spiral cooling water jacket has water inlet 12 and water outlet 13, cooling water flows in spiral cooling water jacket, spiral cooling water jacket outside gas booster cylinder portion can effectively take away the heat generated in the process of gas compression, cooling water flows in water jacket, increases the heat dissipation area and time, reduces the working temperature of booster pump, prevents the damage and performance decline of parts due to overheating, prolongs the service life of booster pump.

[0047] Wherein the stator is any one of various stators such as a distributed winding stator, a concentrated winding stator, an inductor type stator, a permanent magnet stator, etc., the rotor nut is a combination of a rotor and a screw nut, and the rotor is one of various rotors such as a squirrel cage rotor, a salient pole cage rotor, a semi-hard magnetic steel rotor, a soft steel rotor, a salient pole silicon steel rotor, a micro toothed rack soft steel rotor, a permanent magnet rotor, an inductor type rotor, a coil type rotor, a commutator type rotor, etc. Among them, the screw motor shaft adopts one of various screw shafts such as trapezoidal screw shaft, planetary roller screw shaft, ball screw shaft, etc.

[0048] The above various types can be selected, and each type has its own advantages

[0049] Stator type advantages:

[0050] (1) Distributed winding stator, distributed winding can provide more uniform magnetic field distribution, reduce harmonics and electromagnetic noise, improve the running stability and efficiency of the motor;

[0051] (2) Concentrated winding stator, simple structure, low manufacturing cost, and since the winding is concentrated, it is easy to dissipate heat and maintain, at the same time, the concentrated winding can also provide enough electromagnetic force to drive the rotor;

[0052] (3) Inductor type stator (usually refers to the stator of a brushless DC motor), no physical contact is needed to realize current commutation, reducing mechanical wear and friction, improving the reliability and life of the motor, at the same time, inductive control makes the motor respond faster and control more accurately;

[0053] (4) Permanent magnet stator, the magnetic field generated by the permanent magnet is stable and strong, making the motor have high power density and efficiency, in addition, the permanent magnet motor also has the advantages of small size, light weight, low noise, etc.

[0054] Rotor type advantages:

[0055] (1) Squirrel cage rotor (commonly used in induction motors), simple structure, low manufacturing cost, reliable operation, when the motor starts, the current in the rotor will generate a magnetic field by itself, which interacts with the stator magnetic field to drive the rotor to rotate;

[0056] (2) Salient pole cage rotor, based on the squirrel cage rotor, it increases the salient pole design, which helps to improve the magnetic flux distribution of the motor and improve the torque and efficiency of the motor;

[0057] (3) Semi-hard magnetic steel rotor, combining the characteristics of permanent magnets and soft magnetic materials, it has certain self-excitation ability and can change the magnetization state under the action of external magnetic field, suitable for occasions that require dynamic adjustment of magnetic field strength;

[0058] (4) Soft steel rotor is easy to magnetize and demagnetize, and is suitable for occasions that require frequent changes in the direction of the magnetic field. However, it is rarely used in pure induction motors and is more often found in specially designed motors.

[0059] (5) Salient-pole silicon steel rotor: Silicon steel material has low eddy current loss and high resistivity, which helps to reduce the heat generation and energy loss of the motor; the salient-pole design helps to improve the magnetic flux distribution and performance of the motor.

[0060] (6) Micro-gear soft steel rotor: The micro-gear design increases the electromagnetic coupling area between the rotor and the stator, which improves the torque and efficiency of the motor. At the same time, the gear design also helps to reduce the noise and vibration of the motor.

[0061] (7) Permanent magnet rotor: The magnetic field generated by the permanent magnet is stable and strong, which makes the motor have high power density and efficiency. In addition, permanent magnet motors also have the advantages of small size, light weight, low noise and fast response.

[0062] (8) Inductor-type rotor (such as synchronous reluctance motor), the rotation of the motor is achieved by the interaction between the magnetic field generated in the rotor by the inductor (such as coil) and the stator magnetic field. This design makes the motor have high efficiency and good dynamic performance.

[0063] (9) Coil-type rotor (such as synchronous motor), the coil in the rotor is powered by an external power source to generate a magnetic field, which interacts with the stator magnetic field to realize the rotation of the motor. The coil-type rotor makes the motor have higher control accuracy and response speed.

[0064] (10) A commutator-type rotor (such as a DC motor) converts DC power into AC power in the rotor through a commutator (commutator) and carbon brushes to achieve the rotation of the motor. The commutator-type rotor gives the motor a larger starting torque and better speed regulation performance.

[0065] When selecting stator and rotor types, it is necessary to take into account the specific application scenario, performance requirements, and cost considerations.

[0066] As a preferred implementation, the lead screw motor shaft adopts one of various types such as trapezoidal lead screw shaft, planetary roller lead screw shaft, and ball screw shaft. In a gas compressor driven by a lead screw motor for reciprocating motion, the selection of the lead screw motor shaft is crucial for achieving efficient and stable linear motion.

[0067] The following is an overview of the advantages of selecting three types of lead screws: trapezoidal lead screws, planetary roller lead screws, and ball screws:

[0068] The lead screw motor shaft adopts a trapezoidal lead screw shaft, such as... Figure 5 , 6 As shown, specifically,

[0069] (1) Simple structure, low manufacturing cost, the design of trapezoidal screw shaft is relatively simple, the processing and manufacturing cost is lower, it is suitable for large-scale production and cost control requirement higher occasion;

[0070] (2) Strong self-locking ability, the tooth angle of trapezoidal thread is larger, so that the screw shaft has a certain self-locking ability when it is not under external force, which can prevent accidental movement caused by load mutation or power failure.

[0071] (3) Strong carrying capacity, trapezoidal screw shaft can withstand larger axial force and torque, and is suitable for compressor applications that need to withstand larger load.

[0072] The screw motor shaft adopts planetary roller screw shaft, as shown in Figure 7 , 8 The screw rod can be regarded as a sun gear, the roller can be regarded as a planet gear, and the gears on both sides of the roller can ensure the synchronization of the meshing transmission between the roller and the screw rod and the nut and the pure rolling on the end section. It has high carrying capacity, high transmission precision and high efficiency, but due to the limitations of related design technology and processing technology and equipment, its application range is relatively small. The advantages of planetary roller screw and ball screw lie in that they can provide higher rated dynamic load and static load than ball screw. The threaded roller 14 replaces the ball, which can quickly release the load through numerous contact lines, thereby having higher impact resistance.

[0073] In summary, the planetary roller screw can withstand 3 times the static load of the ball screw and has a service life 15 times that of the ball screw. It has the advantages of high carrying capacity, high reliability, strong adaptability, strong stealth ability, and low noise.

[0074] The screw motor shaft adopts a ball screw shaft, as shown in Figure 9 , 10 Specifically,

[0075] (1) High precision and high speed, the ball screw shaft also adopts ball transmission, has the characteristics of high precision and high speed, and can quickly and accurately realize the reciprocating motion of the piston, meet the demand of compressor for high efficiency and stable gas compression;

[0076] (2) Low noise, the stability of ball transmission makes the noise generated by ball screw shaft during operation lower, which helps to improve the working environment of compressor and reduce noise pollution;

[0077] (3) Wide applicability, ball screw shaft is suitable for various load and speed requirements, has high universality and flexibility, which makes it one of the commonly used transmission elements in compressor design.

[0078] In summary, when selecting the type of screw motor shaft, the specific needs of the compressor, performance requirements, and cost considerations should be taken into account. For example, trapezoidal screw shafts are suitable for applications where cost is a high priority. Planetary roller screw shafts and ball screw shafts are more suitable for compressors that require high precision, efficiency, and longevity.

[0079] As a preferred embodiment, the screw motor drive part is selected as a high-torque low-speed servo motor.

[0080] The above-mentioned stator, rotor and screw motor shaft provide multiple types for selection. Users can flexibly assemble appropriate components according to different application scenarios, working conditions and performance indicators, so that the booster pump can meet various complex gas boosting requirements, improving the versatility and adaptability of the product.

[0081] The screw motor drive part corresponds to a set of gas booster cylinder parts, which performs unilateral compression.

[0082] Example 2

[0083] As shown in Figure 11 a screw motor driven gas booster pump, different from example 1, the screw motor drive part corresponds to 2 sets of gas booster cylinder parts, which performs bilateral compression. Bilateral compression of the two sets of symmetrically arranged gas booster cylinder parts can greatly improve the efficiency and capacity of gas boosting, ensuring stable operation of the system.

[0084] The cylinder body of the gas booster cylinder part is a composite cylinder body, which includes an outer layer of high-strength alloy steel cylinder and an inner layer of hydrogen embrittlement-resistant ceramic cylinder. The outer layer of high-strength alloy steel cylinder and the inner layer of ceramic cylinder are in interference fit, and the high-strength alloy steel cylinder and the ceramic cylinder are connected by cold and hot assembly. The wall thickness of the high-strength alloy steel cylinder is larger than that of the ceramic cylinder. The high-strength alloy steel cylinder is one of high-strength steel cylinder, high-strength titanium alloy cylinder and high-strength aluminum alloy cylinder. The ceramic cylinder is one of zirconium oxide ceramic cylinder, aluminum oxide ceramic cylinder, silicon oxide ceramic cylinder, silicon carbide ceramic cylinder, boron carbide ceramic cylinder or boron nitride ceramic cylinder.

[0085] The above structure design has the following advantages:

[0086] (1) The composite cylinder body includes an outer layer of high-strength alloy steel cylinder and an inner layer of ceramic cylinder. The ceramic cylinder is one of aluminum oxide ceramic cylinder, silicon carbide ceramic cylinder, zirconium oxide ceramic cylinder, boron carbide ceramic cylinder or boron nitride ceramic cylinder, and is formed by isostatic pressing and high-temperature sintering. It has the characteristics of high density and good wear resistance, with a Rockwell hardness HRC≥80, which is nearly 10 times higher than the wear resistance of ordinary materials resistant to hydrogen embrittlement, effectively reducing the use cost.

[0087] (2) The composite cylinder is mainly applied to the field of hydrogen compressor, and the cylinder with the composite structure design is suitable for the special environment of hydrogen compression. The inner ceramic cylinder can ensure excellent hydrogen embrittlement resistance, and has good wear resistance. The outer high-strength alloy steel makes up for the low toughness of the ceramic material, solves the problem that the original single material cannot have both high strength and hydrogen embrittlement resistance, and realizes high strength and good hydrogen embrittlement resistance.

[0088] The assembling process is as follows:

[0089] S1, pretreatment, first, the inner ceramic cylinder and the high-strength alloy steel cylinder are subjected to surface processing, wherein the wall thickness of the high-strength alloy steel cylinder should meet the relevant pressure calculation requirements, the inner hole size tolerance of the high-strength alloy steel cylinder should be less than 0.04 mm, the straightness tolerance of the high-strength alloy steel cylinder should be less than 0.04 mm, the cylindricity tolerance of the high-strength alloy steel cylinder should be less than 0.02 mm, and the smoothness of the high-strength alloy steel cylinder should be less than 0.4. The wall thickness of the inner ceramic cylinder should meet the pressure calculation requirements, the outer wall size tolerance of the inner ceramic cylinder should be less than 0.04 mm, the straightness tolerance of the inner ceramic cylinder should be less than 0.04 mm, the cylindricity tolerance of the inner ceramic cylinder should be less than 0.02 mm, and the smoothness of the inner ceramic cylinder should be less than 0.4.

[0090] S2, hot assembly, the high-strength alloy steel cylinder after surface processing in S1 is heated to 400 degrees Celsius and kept for 3 hours, then the inner ceramic cylinder after surface processing in S1 is quickly inserted into the hole of the high-strength alloy steel cylinder after the heated high-strength alloy steel cylinder is taken out from the heating furnace, and naturally cooled to room temperature.

[0091] S3, quality inspection, artificial quality inspection is performed on the surface of the processed product to ensure that the inner wall surface is free of pits, protrusions and deformation. According to the performance test data of the composite cylinder, after the completion of the composite cylinder, the strength meets the design requirements, the coaxiality requirement is less than 0.03 mm, the straightness requirement is less than 0.015 mm, the cylindricity requirement is less than 0.02 mm, the roundness requirement is less than 0.01 mm, and the smoothness requirement is less than 0.1.

[0092] The cylinder of the gas booster cylinder part is a single material metal cylinder, and the single material metal cylinder is sprayed with a wear-resistant material layer on the inside and outside. The wear-resistant material layer is a PVD coating or a CVD coating.

[0093] The PVD coating is a physical vapor deposition, that is, a thin film with certain special functions is deposited on the surface of the substrate. In the process, under vacuum conditions, a physical method is used to gasify the material source surface into gaseous atoms, molecules or partially ionized ions.

[0094] The main advantages of PVD coating are high hardness, high wear resistance, high temperature resistance, low friction coefficient, which can significantly improve the service life and surface finish of the tooling.

[0095] PVD fine kinds include TIN-titanium nitride, CRN-chromium nitride, TICN-titanium carbonitride, TIALN-titanium aluminum nitride, CRAN-chromium aluminum titanium nitride.

[0096] CVD coating belongs to atomic deposition, which is a method of using metal halide vapor, hydrogen and other chemical components to decompose, heat and other gas-solid reactions at high temperature of 950-1050 DEG C, and the deposition is in the form of atomic, ionic, molecular and other atomic scale on the surface of the heated substrate to form a solid deposition layer. The process includes three stages: material gasification, transportation to the substrate and formation of the coating layer on the substrate.

[0097] The composite cylinder is mainly applied to the field of hydrogen compressor, and the cylinder with the spraying structure design is suitable for the special environment of hydrogen compression. The cylinder is made of hydrogen embrittlement resistant material, and the inner and outer parts of the cylinder are sprayed with wear-resistant material by PVD spraying process. The PVD material has the advantages of strong adhesion, high hardness (Vickers 3500), high temperature resistance (600-900 DEG C), low friction coefficient, corrosion and rust prevention and the like. The problem of incompatible strength and hydrogen embrittlement resistance of the original single material is solved, and the effects of high strength and good hydrogen embrittlement resistance are realized.

[0098] Finally, it should be pointed out that: the above is only the preferred embodiment of the utility model, and is not used to limit the utility model, although the utility model is described in detail with reference to the foregoing embodiments, for those skilled in the art, it still can modify the technical scheme recorded in the foregoing embodiments, or make equivalent replacement to part of the technical features, any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. A gas booster pump driven by a screw motor, comprising a booster pump body, the booster pump body comprising a gas booster cylinder part and a screw motor driving part connected together, the gas booster cylinder part comprising a compression cavity, the gas booster cylinder part being provided with an air inlet and an air outlet connected with the compression cavity, the air inlet and the air outlet being provided with one-way valves, and a piston being movably arranged in the compression cavity, characterized in that: The screw rod motor driving part is provided with a screw rod motor shaft capable of reciprocating, and the driving end of the screw rod motor shaft extends into the compression cavity to be fixedly connected or floatingly connected with the piston. The screw rod motor driving part further comprises a screw rod motor shell, the screw rod motor shaft is arranged in the screw rod motor shell along the axial direction of the gas pressurizing cylinder part, the screw rod motor shell is coaxially sleeved from the outside to the inside with a stator and a rotor nut, the inner wall of the rotor nut is provided with a nut part matched with the screw rod motor shaft, the screw rod motor shaft is provided with an anti-rotation structure, and under the action of the stator, the rotor nut rotates, and when the rotor nut rotates, the rotor nut generates a thrust along the axial direction of the screw rod motor shaft due to the inclined action of the nut part, so as to drive the screw rod motor shaft to move along the axial direction of the gas pressurizing cylinder part, and the screw rod motor shaft drives the piston to reciprocate to realize the compression of the gas.

2. A gas booster pump driven by a ball screw motor according to claim 1, characterized in that: The anti-rotation structure comprises a guide key groove arranged on the screw rod motor shaft, and the compression cavity is provided with a guide key matched with the key groove near the end position.

3. A gas booster pump driven by a ball screw motor according to claim 1, characterized in that: The gas pressurizing cylinder part and the screw rod motor shell are coaxially and integrally connected.

4. A gas booster pump driven by a ball screw motor according to claim 1, characterized in that: The gas pressurizing cylinder part is provided with a spiral cooling water jacket outside, the spiral cooling water jacket is provided with a water inlet and a water outlet, and cooling water flows in the spiral cooling water jacket.

5. A gas booster pump driven by a ball screw motor according to claim 1, characterized in that: The stator is any one of a distributed winding stator, a concentrated winding stator, an inductor type stator and a permanent magnet stator, the rotor nut is a combination of a rotor and a screw nut, and the rotor is one of a squirrel cage rotor, a salient pole cage rotor, a semi-hard magnetic steel rotor, a soft steel rotor, a salient pole silicon steel rotor, a micro tooth rack soft steel rotor, a permanent magnet rotor, an inductor type rotor, a coil type rotor and a commutator type rotor.

6. A gas booster pump driven by a ball screw motor according to claim 1, characterized in that: The screw rod motor shaft adopts one of a trapezoidal screw rod shaft, a planetary roller screw rod shaft and a ball screw rod shaft.

7. A gas booster pump driven by a ball screw motor according to claim 1, wherein: The screw rod motor driving part selects a servo motor with high torque and low speed.

8. A gas booster pump driven by a ball screw motor according to claim 1, characterized in that: The gas pressurizing cylinder part corresponding to the screw rod motor driving part has one group or two symmetrically arranged groups, and performs single-sided compression or double-sided compression.

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