Reciprocating compressor stepless gas volume regulation actuator connection structure

Abstract

The present invention discloses a connecting body structure of a stepless air volume regulation actuator for a reciprocating compressor, which relates to the technical field of reciprocating compressors and includes a push rod, a shell, a connecting piece and a sealing assembly. The push rod is used to transmit the power provided by the driving structure to the unloader, and the shell is sleeved on the outside of the push rod. The connecting piece includes a flange portion and a sleeve portion. The first side of the flange portion is used to connect to the second end of the shell, and the second side of the flange portion is used to connect to the outer shell of the driving structure. The sleeve portion is located between the push rod and the shell, and the sleeve portion is provided with a second oil hole, and the second oil hole is connected to the first oil hole. The sealing assembly includes a first end face sealing ring, a second end face sealing ring, a first sealing ring and an oil leakage joint. The oil leakage joint is connected to the first oil hole and is used to recover hydraulic oil when the driving structure is a hydraulic cylinder. Compared with the prior art, the connecting body structure of the present invention can adapt to both hydraulic pressure and electromagnetic force driving modes, and has better versatility.

Description

Technical Field

[0001] The present invention relates to the technical field of reciprocating compressors, in particular to a connecting body structure of a stepless air volume regulation actuator for a reciprocating compressor. Background Art

[0002] As a key dynamic equipment in process industries such as oil refining, chemical industry, and fertilizer industry, reciprocating compressor systems transport high-pressure raw gas media to the production process and are key nodes in the material flow of industrial production. Their safe, stable, and reliable operation is a long-term requirement of enterprises.

[0003] Reciprocating compressors control the gas pressure within the working chamber by changing the volume of the piston and cylinder through the periodic motion of the piston. However, when the initial process design does not match market demand, the unit's exhaust volume needs to be dynamically adjusted to meet production requirements. Currently, the most effective regulation method that both saves energy and meets production gas supply and demand is top-opening the intake valve. Installing an electro-hydraulic servo actuator or electromagnetic actuator on the intake valve allows for rapid and precise control of the unit's flow and pressure. Compared to other regulation methods, it offers advantages such as low engineering implementation difficulty, a wide load adjustment range, and the most significant energy-saving effects.

[0004] Adjustment systems for top-opening intake valves have been publicly disclosed both domestically and internationally. Actuators are driven by either hydraulic pressure or electromagnetic force. Existing actuators are generally classified into two categories based on their drive method, without consideration of universal structural design. Installing different actuators in the same unit makes component interchangeability difficult, significantly complicating on-site installation, maintenance, and spare parts management. Summary of the Invention

[0005] The purpose of the present invention is to provide a reciprocating compressor stepless gas volume regulation actuator connection structure to solve the problems existing in the above-mentioned related technologies and adapt to both hydraulic pressure and electromagnetic force driving modes.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention discloses a reciprocating compressor stepless gas volume regulation actuator connecting body structure, comprising:

[0008] a push rod, wherein a first end of the push rod is used to connect to the top plate of the unloader, and a second end of the push rod is used to connect to the driving end of the driving structure;

[0009] a housing, the housing being sleeved on the outside of the push rod with a gap between the housing and the push rod; the housing being provided with a first oil hole, the two ends of the first oil hole being respectively located on the inner side and the outer side of the housing; the first end of the housing being used for connecting to the valve cover of the compressor;

[0010] A connecting member, the connecting member comprising a flange portion and a sleeve portion; a first side of the flange portion is used to connect to the second end of the housing, and a second side of the flange portion is used to connect to the housing of the drive structure and is in sealing contact with the housing; the sleeve portion is connected to the side of the flange portion facing away from the drive structure, and is located between the push rod and the housing, with a gap between the sleeve portion and the push rod; the sleeve portion is provided with a second oil hole, with two ends of the second oil hole respectively located on the inner side and outer side of the sleeve portion; the second oil hole is butted against the first oil hole;

[0011] A sealing assembly, the sealing assembly comprising a first end face sealing ring, a second end face sealing ring, a first sealing ring and an oil leakage joint; the first end face sealing ring is used to seal the gap between the first side of the flange portion and the shell, and the second end face sealing ring is used to seal the gap between the valve cover and the shell; the first sealing ring is located between the push rod and the shell, and is located on the side of the sleeve portion away from the drive structure, the inner side surface of the first sealing ring is in sealing contact with the push rod, and the outer side surface of the first sealing ring is in sealing contact with the inner side surface of the shell to seal the gap between the push rod and the shell; the oil leakage joint is connected to the first oil hole, and is used to recover hydraulic oil when the drive structure is a hydraulic cylinder.

[0012] Preferably, the sealing assembly also includes an air guide ring and an air leakage joint; the air guide ring is located between the push rod and the shell, and is located on the side of the first sealing ring away from the driving structure, the air guide ring is provided with a first air hole, and the two ends of the first air hole are respectively located on the inner side and the outer side of the air guide ring; the shell is provided with a second air hole, and the two ends of the second air hole are respectively located on the inner side and the outer side of the shell, and the second air hole is connected to the first air hole; the air leakage joint is connected to the second air hole for recovering gas leaked from the compressor.

[0013] Preferably, the sealing assembly also includes a second sealing ring; the second sealing ring is located between the push rod and the shell, and is located on the side of the air guide ring away from the drive structure, the inner side surface of the second sealing ring is in sealing contact with the push rod, and the outer side surface of the second sealing ring is in sealing contact with the inner side surface of the shell to seal the gap between the push rod and the shell, so as to reduce the amount of gas leaked from the compressor to the air guide ring.

[0014] Preferably, the housing is provided with an inner flange, which is located on a side of the second sealing ring away from the driving structure and is used to limit the circumferential position of the second sealing ring; the push rod passes through the inner flange.

[0015] Preferably, the second sealing ring includes a second ring block, an inner sealing ring of the second ring block and an outer sealing ring of the second ring block; the second ring block is located between the push rod and the shell, the inner sealing ring of the second ring block is embedded in the inner side surface of the second ring block, and is used for sealing contact with the push rod; the outer sealing ring of the second ring block is embedded in the outer side surface of the second ring block, and is used for sealing contact with the inner side surface of the shell.

[0016] Preferably, an inner ring groove is provided on the inner side of the air guide ring, and an outer ring groove is provided on the outer side of the air guide ring; one end of the first air hole is connected to the inner ring groove, and the other end of the first air hole is connected to the outer ring groove.

[0017] Preferably, the first sealing ring includes a first ring block, an inner sealing ring of the first ring block and an outer sealing ring of the first ring block; the first ring block is located between the push rod and the shell, the inner sealing ring of the first ring block is embedded in the inner side surface of the first ring block, and is used for sealing contact with the push rod; the outer sealing ring of the first ring block is embedded in the outer side surface of the first ring block, and is used for sealing contact with the inner side surface of the shell.

[0018] Preferably, the second oil hole is arranged obliquely relative to the sleeve portion; the second oil hole is located at one end of the inner side surface of the sleeve portion, which is closer to the driving structure than the second oil hole is located at one end of the outer side surface of the sleeve portion.

[0019] Preferably, when selecting the return spring of the unloader, the following requirements must be met:

[0020]

[0021] When selecting the drive structure, the following requirements must be met:

[0022]

[0023] in:

[0024] p cy : The air pressure in the compressor;

[0025] p0: standard atmospheric pressure;

[0026] p s : The air pressure in the suction chamber of the compressor;

[0027] β: pressure difference coefficient on both sides of the valve plate of the unloader;

[0028] A sv : The area of ​​the valve plate;

[0029] A l : the cross-sectional area of ​​the ejector pin, d1 is the diameter of the section of the push rod close to the driving structure, and the diameter of the section of the push rod away from the driving structure is d2 = 1.5d1;

[0030] f: the friction force on the push rod;

[0031] g: acceleration due to gravity;

[0032] L: the stroke of the unloader;

[0033] α: The installation angle of the unloader, which refers to the angle between the center line of the unloader and the vertical line of the ground;

[0034] m: the sum of the masses of the ejector rod, the outer shell of the unloader, the top plate of the unloader, the pressure fork of the unloader, and the pressure cover of the unloader;

[0035] x1: pre-compression amount of the return spring;

[0036] F g2 : The gas force acting on the valve plate, F g2 =β(p cy -p s )A sv ;

[0037] k: stiffness of the return spring;

[0038] x: compression amount of the return spring;

[0039] F′: the driving force exerted by the driving structure on the ejector during the ejector retraction process;

[0040] F: The driving force of the driving structure on the ejector during the ejection process of the ejector.

[0041] Preferably, when selecting the ejector rod, the diameter of the ejector rod is determined by the following iterative calculation method:

[0042] Initially, substitute d1=10mm into the formula Calculate the driving force in ejection state;

[0043] If F≤800N, then d1=10mm, and the diameter of the push rod is determined;

[0044] If F>800N, the diameter of the push rod needs to be increased, and the diameter of the push rod is increased to d1=12mm;

[0045] Substitute d1=12mm into formula (11) and perform iterative calculation to calculate the ejection state driving force F;

[0046] If 800N≤F≤1600N, then d1=12mm, and the diameter of the push rod is determined;

[0047] If F>1600N, the diameter of the push rod needs to be increased, d1=14mm, and the strength is sufficient to meet the use. The iterative calculation is completed and the diameter of the push rod is determined.

[0048] Compared with the related art, the present invention has achieved the following technical effects:

[0049] The connecting piece of the present invention has a flange portion, which is used to connect to the outside of the driving structure. The driving structure here can be either a hydraulic cylinder or an electromagnetic driving structure, so that the connecting body can adapt to both hydraulic pressure and electromagnetic force driving modes, thereby improving overall versatility.

[0050] In a preferred embodiment of the present invention, the second side of the flange portion is brought into sealing contact with the outer shell of the driving structure, and the gap between the first side of the flange portion and the shell is sealed by a first end face sealing ring, thereby guiding the leaked hydraulic oil along the gap between the sleeve portion and the push rod to the second oil hole. The hydraulic oil reaches the oil leakage joint through the second oil hole and the first oil hole, thereby realizing the recovery of the hydraulic oil, thereby maintaining cleanliness and reducing the waste of hydraulic oil.

[0051] In a preferred embodiment of the present invention, the sealing assembly further includes an air guide ring and a leaking joint. Because the second end face sealing ring seals the gap between the valve cover and the housing, gas leaking from the suction chamber flows along the ejector pin to the air guide ring, then through the first and second air holes to the leaking joint, thereby recovering the leaked gas.

[0052] In a preferred embodiment of the present invention, the sealing assembly further includes a second sealing ring. The second sealing ring is positioned between the push rod and the housing, on the side of the air guide ring facing away from the drive structure. The inner side of the second sealing ring seals against the push rod, while the outer side of the second sealing ring seals against the inner side of the housing, thereby sealing the gap between the push rod and the housing and reducing the amount of gas leaking from the compressor into the air guide ring. The second sealing ring improves sealing performance, requiring a higher pressure for leaking gas to reach the air guide ring, thereby blocking airflow to a certain extent and reducing gas leakage.

[0053] In the preferred embodiment of the present invention, a specific calculation method related to the selection of the return spring and the ejector rod is provided, which facilitates the staff to quickly and accurately select the appropriate components for use, improves work efficiency, and ensures the safe operation of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0055] Figure 1 A schematic diagram of the connecting structure of a stepless air volume regulation actuator for a reciprocating compressor according to an embodiment of the present invention;

[0056] Figure 2 for Figure 1 Assembly diagram of the middle structure, drive structure, unloader, and compressor;

[0057] Figure 3 A schematic diagram of a force analysis of the connecting structure of the stepless gas volume regulation actuator of a reciprocating compressor according to an embodiment of the present invention;

[0058] Figure 4 Schematic diagram comparing the compression amount of the return spring and the corresponding spring force under different working conditions.

[0059] In the figure: 1-valve disc; 2-valve seat; 3-pressure fork; 4-buffer culvert; 5-outer shell; 6-top plate; 7-valve cover seal ring; 8-valve cover; 9-second end face seal ring; 10-second ring block outer seal ring B; 11-leakage joint; 12-air guide ring; 13-first ring block; 14-first ring block outer seal ring A; 15-oil leakage joint; 16-connector; 17-first end face seal ring; 18-driving end; 19-driving Structure; 20- ejector pin; 21- first ring block inner seal ring A; 22- first ring block inner seal ring B; 23- first ring block outer seal ring B; 24- housing; 25- second ring block outer seal ring A; 26- first ring block inner seal ring A; 27- second ring block; 28- second ring block inner seal ring B; 29- gland; 30- return spring; 31- suction chamber housing; 32- compressor cylinder wall; 33- noise reduction gasket; DETAILED DESCRIPTION

[0060] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0061] The purpose of the present invention is to provide a reciprocating compressor stepless gas volume regulation actuator connection structure to solve the problems existing in the above-mentioned related technologies and adapt to both hydraulic pressure and electromagnetic force driving modes.

[0062] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0063] Reference Figures 1 to 4The present embodiment provides a reciprocating compressor stepless air volume regulation actuator connecting body structure (hereinafter referred to as the connecting body), including a push rod 20, a shell 24, a connecting member 16 and a sealing assembly.

[0064] The first end of the push rod 20 is used to connect to the top plate 6 of the unloader, and the second end of the push rod 20 is used to connect to the drive end 18 of the drive structure 19. The housing 24 is sleeved on the outside of the push rod 20, leaving a gap with the push rod 20. The housing 24 is provided with a first oil hole, and the two ends of the first oil hole are respectively located on the inner side and the outer side of the housing 24. The first end of the housing 24 is used to connect to the valve cover 8 of the compressor. The connecting member 16 includes a flange portion and a sleeve portion. The first side of the flange portion is used to connect to the second end of the housing 24, and the second side of the flange portion is used to connect to the outer shell of the drive structure 19 and is in sealing contact with the outer shell of the drive structure 19. The sleeve portion is connected to the side of the flange portion facing away from the drive structure 19, and the sleeve portion is located between the push rod 20 and the housing 24, leaving a gap with the push rod 20. The sleeve portion is provided with a second oil hole, and the two ends of the second oil hole are respectively located on the inner side and the outer side of the sleeve portion. The second oil hole is connected to the first oil hole. The sealing assembly includes a first end face sealing ring 17, a second end face sealing ring 9, a first sealing ring, and an oil leakage joint 15. The first end face sealing ring 17 is used to seal the gap between the first side of the flange portion and the housing 24, and the second end face sealing ring 9 is used to seal the gap between the valve cover 8 and the housing 24. The first sealing ring is located between the push rod 20 and the housing 24, and is located on the side of the sleeve portion facing away from the drive structure 19. The inner side of the first sealing ring is in sealing contact with the push rod 20, and the outer side of the first sealing ring is in sealing contact with the inner side of the housing 24 to seal the gap between the push rod 20 and the housing 24. The oil leakage joint 15 is connected to the first oil hole and is used to recover hydraulic oil when the drive structure 19 is a hydraulic cylinder.

[0065] The connector works as follows:

[0066] The driving structure 19 pushes out and retracts the push rod 20 during operation, and transmits power to the unloader located in the suction chamber of the compressor through the push rod 20, thereby controlling the movement of the valve plate 1 of the unloader to realize the opening and closing of the suction chamber of the compressor.

[0067] Connector 16 has a flange portion that connects to the outside of drive structure 19. Drive structure 19 can be either a hydraulic cylinder or an electromagnetic drive structure, allowing the connector to accommodate both hydraulic and electromagnetic drive modes. A stopper structure can be provided on the second side of the flange portion to align it with the housing of drive structure 19.

[0068] When the drive structure 19 is a hydraulic cylinder, there may be a problem of hydraulic oil leakage in the hydraulic cylinder. To solve this problem, this embodiment seals the second side of the flange portion with the housing of the drive structure 19, and seals the gap between the first side of the flange portion and the housing 24 using the first end face sealing ring 17. This guides the leaked hydraulic oil along the gap between the sleeve portion and the push rod 20 to the second oil hole. The hydraulic oil then reaches the leaking oil joint 15 through the second oil hole and the first oil hole, realizing hydraulic oil recovery, thereby maintaining cleanliness and reducing hydraulic oil waste.

[0069] The gas in the suction chamber may leak along the position of the push rod 20. The gas pressure is relatively high and it is easy to cause danger after leakage. As a possible example, in this embodiment, the sealing assembly also includes an air guide ring 12 and a leakage joint 11. The air guide ring 12 is located between the push rod 20 and the shell 24, and is located on the side of the first sealing ring away from the drive structure 19. The air guide ring 12 is provided with a first air hole, and the two ends of the first air hole are respectively located on the inner side and the outer side of the air guide ring 12. The shell 24 is provided with a second air hole, and the two ends of the second air hole are respectively located on the inner side and the outer side of the shell 24, and the second air hole is connected to the first air hole. The leakage joint 11 is connected to the second air hole and is used to recover the gas leaked from the compressor.

[0070] Since the second end face sealing ring 9 seals the gap between the valve cover 8 and the housing 24, the gas leaking from the suction chamber flows along the push rod 20 to the air guide ring 12, and then reaches the leakage joint 11 through the first air hole and the second air hole, thereby recovering the leaked gas.

[0071] To reduce the amount of gas leaking from the suction chamber, as a possible example, in this embodiment, the sealing assembly further includes a second sealing ring. The second sealing ring is located between the ejector pin 20 and the housing 24, and on the side of the air guide ring 12 facing away from the drive structure 19. The inner side of the second sealing ring is in sealing contact with the ejector pin 20, and the outer side of the second sealing ring is in sealing contact with the inner side of the housing 24, thereby sealing the gap between the ejector pin 20 and the housing 24 and reducing the amount of gas leaking from the compressor to the air guide ring 12.

[0072] The second sealing ring can improve the sealing performance so that the leaked gas needs a higher pressure to reach the gas guide ring 12, thereby blocking the airflow to a certain extent and reducing gas leakage.

[0073] The axial positioning reference for the first sealing ring, air guide ring 12, and second sealing ring between the ejector pin 20 and the housing 24 can be provided by the housing 24 or by a positioning member fixed to the housing 24. As one possible example, in this embodiment, the housing 24 is provided with an inner flange, located on the side of the second sealing ring facing away from the drive structure 19, to limit the circumferential position of the second sealing ring. The ejector pin 20 passes through the inner flange.

[0074] The inner flange limits the second sealing ring on the side away from the drive structure 19, and the sleeve portion limits the first sealing ring on the side close to the drive structure 19, thereby clamping the first sealing ring, the air guide ring 12 and the second sealing ring between the inner flange and the sleeve portion.

[0075] The second sealing ring can take a variety of specific forms, as long as it can achieve the aforementioned sealing purpose. As one possible example, in this embodiment, the second sealing ring includes a second ring block 27, an inner sealing ring of the second ring block, and an outer sealing ring of the second ring block. The second ring block 27 is positioned between the ejector pin 20 and the housing 24. The inner sealing ring of the second ring block is embedded in the inner side of the second ring block 27 and is provided for sealing contact with the ejector pin 20. The outer sealing ring of the second ring block is embedded in the outer side of the second ring block 27 and is provided for sealing contact with the inner side of the housing 24.

[0076] Exemplarily, the second ring block inner seal includes a second ring block inner seal A26 and a second ring block inner seal B28, which are separated by a certain distance. The second ring block outer seal includes a second ring block outer seal A25 and a second ring block outer seal B10, which are separated by a certain distance. The second ring block inner seal A26 and the second ring block outer seal A25 are located at the end of the second ring block 27 that is closer to the drive structure 19, while the second ring block inner seal B28 and the second ring block outer seal B10 are located at the end of the second ring block 27 that is away from the drive structure 19.

[0077] To improve the efficiency of leaked airflow, as a possible example, in this embodiment, an inner groove is provided on the inner side of the air guide ring 12, and an outer groove is provided on the outer side of the air guide ring 12. One end of the first air hole is connected to the inner groove, and the other end of the first air hole is connected to the outer groove. The leaking joint 11 can collect gas along the entire circumference simultaneously through the outer groove.

[0078] Similarly, an outer annular groove may also be provided at one end of the first oil hole located on the outer side surface of the housing 24 , so that the oil leakage joint 15 can collect the hydraulic oil in the entire circumferential direction at the same time.

[0079] The first sealing ring can take a variety of specific forms, as long as they can achieve the aforementioned sealing purpose. As one possible example, in this embodiment, the first sealing ring includes a first ring block 13, an inner sealing ring of the first ring block, and an outer sealing ring of the first ring block. The first ring block 13 is positioned between the push rod 20 and the housing 24. The inner sealing ring of the first ring block is embedded in the inner side of the first ring block 13 and is provided for sealing contact with the push rod 20. The outer sealing ring of the first ring block is embedded in the outer side of the first ring block 13 and is provided for sealing contact with the inner side of the housing 24.

[0080] Exemplarily, the first ring block inner seal includes a first ring block inner seal A21 and a first ring block inner seal B22, which are separated by a certain distance. The first ring block outer seal includes a first ring block outer seal A14 and a first ring block outer seal B23, which are separated by a certain distance. The first ring block inner seal A21 and the first ring block outer seal A14 are located at the end of the first ring block 13 closer to the drive structure 19, while the first ring block inner seal B22 and the first ring block outer seal B23 are located at the end of the first ring block 13 away from the drive structure 19.

[0081] Exemplarily, the lip direction of the second ring block inner sealing ring A26 and the second ring block inner sealing ring B28 is toward the valve cover 8 to prevent gas leakage in the suction chamber. The lip direction of the first ring block inner sealing ring A21 is toward the drive structure 19 to prevent the hydraulic oil from continuing to flow to the air guide ring 12. The lip direction of the first ring block inner sealing ring B22 is toward the air guide ring 12 to prevent the gas from continuing to flow to the sleeve part. Through the above-mentioned lip orientation design, the air leakage joint 11 and the oil leakage joint 15 can collect the leaked gas and hydraulic oil respectively. In addition, by distributing multiple sealing rings in series along the axial direction of the push rod 20, the sealing effect can be improved. The grooves in which each sealing ring is embedded are preferably open grooves to facilitate installation and disassembly.

[0082] To facilitate the flow of hydraulic oil to the oil leakage joint 15, as a possible example, in this embodiment, the second oil hole is arranged at an angle relative to the sleeve portion. The second oil hole is located at one end of the inner side surface of the sleeve portion, closer to the drive structure 19 than the second oil hole is located at one end of the outer side surface of the sleeve portion.

[0083] During use, by positioning the driving structure 19 above the push rod 20 , the hydraulic oil flows downward under the action of gravity and at the same time flows outward along the second oil hole arranged obliquely, so as to facilitate the collection of the hydraulic oil by the oil leakage joint 15 .

[0084] For example, the structure of the unloader can be described in patent document CN110206712A. The unloader clamps the end of the push rod 20 facing away from the drive structure 19 from both sides by means of a top plate 6 and a pressure cover 29. The top plate 6 and the pressure rod are both fixedly connected to the outer shell 5, which is in turn fixedly connected to the pressure fork 3, thereby enabling the pressure fork 3 and the push rod 20 to move synchronously.

[0085] During the ejection stroke of the ejector pin 20, the ejection state driving force F (hydraulic pressure or electromagnetic force) provided by the driving structure 19 pushes the ejector pin 20 to move. The ejector pin 20 overcomes the friction force and moves. The ejector plate 6 overcomes the thrust of the return spring 30 and moves. When the fork leg of the pressure fork 3 contacts the valve plate 1, the pressure fork 3 overcomes the thrust of the intake valve spring and the gas pressure difference on both sides of the valve plate 1 and moves. Then the valve plate 1 opens, and the gas in the compressor flows into the intake chamber. When the outer shell 5 contacts the noise reduction gasket 33 on the valve seat 2, it no longer moves, and the stroke of the pressure fork 3 is L. When the amount of gas returned to the intake chamber by the compressor meets the process regulation requirements, the withdrawal stroke of the ejector pin 20 is opened.

[0086] During the withdrawal stroke of the push rod 20, the pressure fork 3 moves under the assistance of the pressure difference on both sides and the suction valve spring. The top plate 6 moves with the assistance of the return spring 30. The push rod 20 moves by overcoming the friction force and the withdrawal state driving force F' provided by the drive structure 19. When the pressure fork 3 separates from the valve plate 1, the valve plate 1 returns to its original position under the action of the suction valve spring and gas force. The suction chamber closes, and the compressor begins normal compression, exhaust, and expansion operations. The top plate 6 moves with the assistance of the return spring 30, and the push rod 20 moves by overcoming the friction force and the driving force provided by the drive structure 19.

[0087] It should be noted that in order to reduce the impact force during the withdrawal of the push rod 20, the driving force exerted by the drive structure 19 on the push rod 20 cannot be zero during the withdrawal stroke, and the greater the pressure difference across the valve plate 1, the greater the driving force exerted by the drive structure 19 on the push rod 20. In this embodiment, the driving force in the withdrawal state ranges from 200N to 800N.

[0088] As a possible example, in this embodiment, a calculation process related to selection is also provided to facilitate component selection.

[0089] The calculation process is described in detail below, including the calculation of the driving force F in the ejection state, the driving force F′ in the retraction state, the stiffness k of the return spring 30 and the diameter d of the ejector pin 20 .

[0090] 1) Design parameters

[0091] A={p cy ,p0,p s ,β,A sv ,A l ,f,g,L,α,m,x1,F g2}

[0092] in,

[0093] p cy : During the compressor reflux process, due to gas resistance and other reasons, the surface pressure on both sides of the valve plate 1 is different. Through computer simulation, it is found that the air pressure acting on the valve plate 1 is about 0.001MPa;

[0094] p0: standard atmospheric pressure;

[0095] p s : The air pressure in the suction chamber of the compressor;

[0096] β: pressure difference coefficient on both sides of valve plate 1 of the unloader;

[0097] A sv : The area of ​​valve plate 1 (the areas on both sides are the same);

[0098] A l : The cross-sectional area of ​​the ejector pin 20, d1 is the diameter of the section of the push rod 20 close to the drive structure 19, and the diameter of the section of the push rod 20 away from the drive structure 19 is d2=1.5d1;

[0099] f: friction force on the ejector pin 20;

[0100] g: acceleration due to gravity;

[0101] L: stroke of unloader;

[0102] α: The installation angle of the unloader, which refers to the angle between the center line of the unloader and the vertical line of the ground;

[0103] m: the sum of the masses of the ejector rod 20, the outer shell 5 of the unloader, the top plate 6 of the unloader, the pressure fork 3 of the unloader, and the pressure cover 29 of the unloader;

[0104] x1: pre-compression amount of the return spring 30;

[0105] F g2 : Gas force acting on valve plate 1, F g2 =β(p cy -p s )A sv ;

[0106] 2) Withdrawal state driving force F'

[0107] In order to reduce the impact force of the actuator during the withdrawal process, the withdrawal state driving force F′ cannot be zero, and the higher the suction pressure, the larger the withdrawal state driving force F′ needs to be to reduce the impact force of the withdrawal process. The withdrawal state driving force F′ is between 200N and 800N.

[0108] 3) Stiffness k of the return spring 30

[0109] The differential equation of motion of the withdrawal process is as follows:

[0110]

[0111] in,

[0112] Unloader ejection acceleration;

[0113] F′: driving force during the unloader withdrawal process (hydraulic force or electromagnetic force provided by the driving structure 19);

[0114] F g1 : Chamber pressure force, F g1 =(p s -p0)A l ;

[0115] k: stiffness of the return spring 30 of the unloader;

[0116] x: compression amount of the unloader's return spring 30;

[0117] The initial conditions of formula 1) are as follows:

[0118]

[0119] in,

[0120] Unloader ejection speed;

[0121] x(0): initial displacement of the unloader during ejection;

[0122] From formulas 1) and 2), we can get the displacement equation of the withdrawal process:

[0123]

[0124] in:

[0125] t: represents the movement time of the unloader withdrawal process;

[0126] The boundary conditions of formula 3) are as follows:

[0127] When t = t′ max When x=x1 4)

[0128] in:

[0129] t′ max : Considering the regulating effect of the gas volume regulating system, the value should be within the range of 0.008s to 0.02s;

[0130] The spring stiffness can be obtained from formula 3) and formula 4):

[0131]

[0132] in:

[0133] F s1 :i represents 1, 2, where F s1Represents the pre-compression force of the unloader return spring 30, F s2 represents the maximum spring force of the return spring 30 when the unloader moves to the bottom dead center;

[0134] Considering that the unloader can be withdrawn to the upper limit during the withdrawal process, the spring stiffness needs to meet the following conditions:

[0135]

[0136] 4) Ejection state driving force F,

[0137] The differential equation of motion during the ejection process is as follows:

[0138]

[0139] in,

[0140] F: driving force of the unloader ejection process (hydraulic pressure or electromagnetic force provided by the driving structure 19);

[0141] The initial conditions of Equation 7) are as follows:

[0142]

[0143] From formulas 7) and 8), we can get the displacement equation of the ejection process:

[0144]

[0145] The boundary conditions of formula 9) are as follows:

[0146] When t = t max When x=x1+L10)

[0147] in:

[0148] t max : Considering the regulating effect of the gas volume regulating system, the value should be within the range of 0.008s to 0.02s;

[0149] The driving force in the ejection state is obtained from formulas 9) and 10):

[0150]

[0151] 5) Diameter of ejector pin 20

[0152] i: Considering that the ejector pin 20 is subjected to high-frequency and high-intensity impact loads, its diameter should not be less than 10 mm;

[0153] ii: To increase the strength of the ejector pin 20, a variable diameter structure is used. The diameter d1 of the area in contact with the sealing component is consistent with the inner diameter of the sealing component. The diameter needs to be selected based on the standard specifications of conventional sealing rings. The diameter of the area not in contact with the sealing component is d2 = 1.5d1.

[0154] iii: The diameter d1 of the ejector pin 20 needs to be calculated using an iterative method:

[0155] Initially, substitute d1 = 10 mm into formula (11) to calculate the driving force in the ejection state;

[0156] If F≤800N, then d1=10mm, and the diameter of the ejector pin 20 is determined;

[0157] If F>800N, the diameter of the push rod 20 needs to be increased, and the diameter of the push rod 20 is increased to d1=12mm;

[0158] Substitute d1=12mm into formula (11) and perform iterative calculation to calculate the driving force in the ejection state;

[0159] If 800N≤F≤1600N, then d1=12mm, and the diameter of the ejector pin 20 is determined;

[0160] If F>1600N, the diameter of the push rod 20 needs to be increased, d1=14mm, and the strength is sufficient to meet the use. The iterative calculation is completed and the diameter of the push rod 20 is determined.

[0161] In order to explain the stress situation more clearly, the following Figure 3 and Figure 4 , and analyze the force conditions of the entire movement process.

[0162] Reference Figure 3 , all the moving parts of the actuator are simplified as a mass block (mass is m), and the forces acting on the actuator include: gravity mgcosα, the driving force F in the ejection state, the driving force F′ in the retraction state, the elastic force kx of the return spring 30, and the force F acting on the valve plate 1 g2 , the gas pressure in the air chamber exerts a force F on the ejector pin 20 g1 , friction force f.

[0163] There are four working states of the actuator. The first is the initial state of ejection. The actuator is at the upper limit position, and the compression amount of the return spring 30 is x1. The ejection process occurs during the suction process of the reciprocating compressor. Since the suction valve disc 1 is automatically opened during the suction process, the actuator will not be affected by the valve disc 1 during the ejection process. Therefore, the forces include F, mgcosα, kx1, f, and F. g1 ;

[0164] The second is the final ejection state. Under the action of the ejection state driving force, the actuator moves downward to the lower limit. The return spring 30 is compressed by x1+L at this time. The actuator will remain stationary under the action of the ejection state driving force. Therefore, the force includes F, mgcosα, k(x1+L), f, F g1 .

[0165] The third is the initial state of withdrawal. When the amount of refluxed gas meets the process regulation requirements, the driving force switches to the withdrawal state driving force F'. Under the action of the reset spring 30 and the gas force, the moving parts overcome the withdrawal state driving force F', friction, etc., and the moving parts move upward along the guide assembly. The reset spring 30 is compressed by x1+L at this time. The initial state of withdrawal is in the compression process. The suction valve disc 1 automatically closes and contacts the pressure fork 3. The valve disc 1 will exert an upward force on the pressure fork 3. Therefore, the forces include F, mgcosα, kx1, f, and F. g1 、F g2 .

[0166] The fourth state is the final state of withdrawal. Under the push of the return spring 30, the gas force, and the force of the valve plate 1, the actuator moves to the upper limit. The return spring 30 is compressed by x1 at this time, and the pressure fork 3 is separated from the valve plate 1. The actuator is not affected by the force of the valve plate 1. Therefore, the forces include F, mgcosα, kx1, f, and F g1 ; From state 1 to state 2, the time required is t max , from state three to state four, the time required is t′ max .

[0167] Reference Figure 4 In the initial ejection / final withdrawal state, the compression amount of the return spring 30 is x1, and the elastic force of the return spring 30 is F s1 In the final ejection / initial withdrawal state, the compression amount of the return spring 30 is x1+L, and the elastic force of the return spring 30 is F s2 .

[0168] Referring to the above calculation method, the following examples are used to illustrate the calculation involved in component selection in this embodiment, combining the relevant parameters of two specific compressors. In actual application, it is not limited to the compressor example described below. The calculation process mainly includes:

[0169] (1) Clarify the design parameters, as shown in Table 1, which includes the design parameters of two different compressors:

[0170] Table 1 Energy-saving control system dimensions

[0171]

[0172]

[0173] (2) Based on the data in the first step, the driving force, the elastic force of the return spring 30, the diameter of the push rod 20, etc. are obtained by combining the calculation method of the actuator key parameters;

[0174] 1. Gas force

[0175] Compressor 1:

[0176] Compressor 2:

[0177] 2. The inlet pressure of reciprocating compressor 1 is low, and the driving force in the withdraw state is 200N. The inlet pressure of reciprocating compressor 2 is high, and the driving force in the withdraw state is 500N.

[0178] 3. Stiffness of return spring 30

[0179] t′ max and t max If the value is 0.008s, then:

[0180] Compressor 1:

[0181] Solving for k = 51874.75 N / m

[0182] Compressor 2:

[0183] Solving for k = 76137.98 N / m

[0184] Considering that the unloader can be withdrawn to the upper limit during the withdrawal process, the spring stiffness needs to meet the following conditions:

[0185] Compressor 1:

[0186] Compressor 2:

[0187] The stiffness of the return spring 30 in both working conditions 1 and 2 meets the requirements.

[0188] 4. Driving force of ejection state

[0189] Compressor 1:

[0190]

[0191] Compressor 2:

[0192]

[0193] Ejection state driving force constraints: During the ejection holding process, the actuator needs to be kept in the ejection state. The ejection state driving force must be greater than the combined force of the gas force, gravity, and maximum displacement spring force. The constraints are as follows:

[0194] Compressor 1: F ≥ F g1 -mgcosα+f+k(x1+L)=412.08N

[0195] Compressor 2: F ≥ F g1 -mgcosα+f+k(x1+L)=900.21N

[0196] The ejection driving force of compressors 1 and 2 meets the requirements.

[0197] 5. Diameter of ejector pin 20

[0198] In "4. Ejection State Driving Force", if the ejection state driving force of compressor 1 is less than 800N, then:

[0199] d1=10mm,d2=1.5d1=15mm

[0200] The ejection driving force of compressor 2 is greater than 800N. It is necessary to increase the diameter of ejector pin 20. Substitute d1 = 12mm into the formula and perform iterative calculation to calculate the ejection driving force:

[0201]

[0202] 800N≤F≤1600N, then d1=12mm, and the diameter of the push rod 20 in working condition 2 is determined.

[0203] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A reciprocating compressor stepless air volume regulation actuator connection structure, characterized in that: include: a push rod, wherein a first end of the push rod is used to connect to the top plate of the unloader, and a second end of the push rod is used to connect to the driving end of the driving structure; a housing, the housing being sleeved on the outside of the push rod with a gap between the housing and the push rod; the housing being provided with a first oil hole, the two ends of the first oil hole being respectively located on the inner side and the outer side of the housing; the first end of the housing being used for connecting to the valve cover of the compressor; A connecting piece, the connecting piece includes a flange portion and a sleeve portion; the first side of the flange portion is used to connect to the second end of the shell, and the second side of the flange portion is used to connect to the shell of the drive structure and is in sealing contact with the shell; the drive structure is a hydraulic cylinder or an electromagnetic drive structure, so that the connecting body structure of the reciprocating compressor stepless gas volume adjustment actuator can adapt to both hydraulic and electromagnetic drive modes; the sleeve portion is connected to the side of the flange portion away from the drive structure, the sleeve portion is located between the push rod and the shell, and a gap is left with the push rod; the sleeve portion is provided with a second oil hole, the two ends of the second oil hole are respectively located on the inner side and the outer side of the sleeve portion; the second oil hole is connected to the first oil hole; A sealing assembly, the sealing assembly comprising a first end face sealing ring, a second end face sealing ring, a first sealing ring and an oil leakage joint; the first end face sealing ring is used to seal the gap between the first side of the flange portion and the shell, and the second end face sealing ring is used to seal the gap between the valve cover and the shell; the first sealing ring is located between the push rod and the shell, and is located on the side of the sleeve portion away from the drive structure, the inner side surface of the first sealing ring is in sealing contact with the push rod, and the outer side surface of the first sealing ring is in sealing contact with the inner side surface of the shell to seal the gap between the push rod and the shell; the oil leakage joint is connected to the first oil hole, and is used to recover hydraulic oil when the drive structure is a hydraulic cylinder.

2. The reciprocating compressor stepless air volume regulation actuator connection structure according to claim 1, characterized in that: The sealing assembly also includes an air guide ring and an air leakage joint; the air guide ring is located between the push rod and the shell, and is located on the side of the first sealing ring away from the drive structure, the air guide ring is provided with a first air hole, and the two ends of the first air hole are respectively located on the inner side and the outer side of the air guide ring; the shell is provided with a second air hole, and the two ends of the second air hole are respectively located on the inner side and the outer side of the shell, and the second air hole is connected to the first air hole; the air leakage joint is connected to the second air hole for recovering gas leaked from the compressor.

3. The connecting structure of the stepless air volume regulation actuator for a reciprocating compressor according to claim 2, characterized in that: The sealing assembly also includes a second sealing ring; the second sealing ring is located between the push rod and the shell, and is located on the side of the air guide ring away from the drive structure, the inner side surface of the second sealing ring is in sealing contact with the push rod, and the outer side surface of the second sealing ring is in sealing contact with the inner side surface of the shell to seal the gap between the push rod and the shell, so as to reduce the amount of gas leaked from the compressor to the air guide ring.

4. The reciprocating compressor stepless air volume regulation actuator connection structure according to claim 3, characterized in that: The housing is provided with an inner flange, which is located on a side of the second sealing ring away from the driving structure and is used to limit the circumferential position of the second sealing ring; the push rod passes through the inner flange.

5. The reciprocating compressor stepless air volume regulation actuator connection structure according to claim 3, characterized in that: The second sealing ring includes a second ring block, an inner sealing ring of the second ring block, and an outer sealing ring of the second ring block; the second ring block is located between the push rod and the shell, the inner sealing ring of the second ring block is embedded in the inner side surface of the second ring block, and is used for sealing contact with the push rod; the outer sealing ring of the second ring block is embedded in the outer side surface of the second ring block, and is used for sealing contact with the inner side surface of the shell.

6. The reciprocating compressor stepless air volume regulation actuator connection structure according to claim 2, characterized in that: An inner ring groove is provided on the inner side of the air guide ring, and an outer ring groove is provided on the outer side of the air guide ring; one end of the first air hole is connected to the inner ring groove, and the other end of the first air hole is connected to the outer ring groove.

7. The reciprocating compressor stepless air volume regulation actuator connection structure according to claim 1, characterized in that: The first sealing ring includes a first ring block, an inner sealing ring of the first ring block and an outer sealing ring of the first ring block; the first ring block is located between the push rod and the shell, the inner sealing ring of the first ring block is embedded in the inner side surface of the first ring block, and is used for sealing contact with the push rod; the outer sealing ring of the first ring block is embedded in the outer side surface of the first ring block, and is used for sealing contact with the inner side surface of the shell.

8. The reciprocating compressor stepless air volume regulation actuator connection structure according to claim 1, characterized in that: The second oil hole is arranged obliquely relative to the sleeve portion; the second oil hole is located at one end of the inner side surface of the sleeve portion, which is closer to the driving structure than the second oil hole is located at one end of the outer side surface of the sleeve portion.

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