Diaphragm and membrane compressor

Abstract

The application relates to a diaphragm and a diaphragm compressor. The diaphragm comprises a first diaphragm layer, a second diaphragm layer and a third diaphragm layer, the first diaphragm layer comprises a first center part, a first edge part and a first mounting part; the second diaphragm layer comprises a second center part, a second edge part and a second mounting part; the second diaphragm layer is located between the first diaphragm layer and the third diaphragm layer; the third diaphragm layer comprises a third center part, a third edge part and a third mounting part; the first center part, the second center part and the third center part are opposite in the thickness direction of the diaphragm; the first edge part, the second edge part and the third edge part are opposite in the thickness direction of the diaphragm; and the sum of the thicknesses of the first center part, the second center part and the third center part is greater than the sum of the thicknesses of the first edge part, the second edge part and the third edge part. The thickness of the edge part of the diaphragm of the application is smaller than the thickness of the center part, the rigidity of the edge part of the diaphragm is smaller than the rigidity of the center part, the deformation of the diaphragm is more favorable, and the air suction amount of the air-side diaphragm cavity during the air suction process can be improved.

Description

Technical Field

[0001] This invention relates to the field of diaphragm compressor equipment technology, and in particular to a diaphragm and diaphragm compressor. Background Technology

[0002] A diaphragm compressor is a special type of positive displacement compressor suitable for compressing, transporting, and bottling rare gases, as well as flammable, explosive, toxic, and harmful gases. The diaphragm is a crucial component of the entire unit, with a typical lifespan of only about 700 hours. Furthermore, with market demand, the intake conditions required for diaphragm compressors have expanded from negative pressure to high pressure. However, existing diaphragms cannot meet the intake volume requirements of various intake conditions, especially under negative pressure intake conditions. Because the intake pressure is insufficient to drive the diaphragm from its flat, central position towards the oil-side cavity, the diaphragm under negative pressure intake conditions can only move to the central position and cannot deform towards the oil-side cavity. Consequently, the actual intake volume is only half of the design value, resulting in a small actual intake volume. Summary of the Invention

[0003] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a diaphragm, wherein the thickness of the edge portion of the diaphragm is less than the thickness of the center portion, and the stiffness of the edge portion is less than the stiffness of the center portion, which is more conducive to the deformation of the diaphragm and can increase the intake volume of the gas-side diaphragm cavity during the intake process under low negative pressure intake conditions.

[0004] An embodiment of the present invention provides a diaphragm compressor.

[0005] The membrane in this embodiment of the invention includes:

[0006] A first film layer, the first film layer comprising a first central portion, a first edge portion and a first mounting portion sequentially distributed along the radial direction of the film;

[0007] The second film layer includes a second central portion, a second edge portion, and a second mounting portion sequentially distributed radially along the film; and

[0008] A third film layer, wherein the second film layer is located between the first film layer and the third film layer, the third film layer includes a third central portion, a third edge portion and a third mounting portion sequentially distributed along the radial direction of the film, the first central portion, the second central portion and the third central portion are opposite to each other in the thickness direction of the film, the first edge portion, the second edge portion and the third edge portion are opposite to each other in the thickness direction of the film, the first mounting portion, the second mounting portion and the third mounting portion are opposite to each other in the thickness direction of the film, and the sum of the thicknesses of the first central portion, the second central portion and the third central portion is greater than the sum of the thicknesses of the first edge portion, the second edge portion and the third edge portion.

[0009] In this embodiment of the invention, the thickness of the edge portion of the diaphragm is less than the thickness of the center portion, and the stiffness of the edge portion of the diaphragm is less than the stiffness of the center portion, which is more conducive to the deformation of the diaphragm and can increase the amount of air intake in the air-side diaphragm cavity during the air intake process.

[0010] In some embodiments, the thickness of the second central portion is equal to the thickness of the second edge portion.

[0011] In some embodiments, the thickness of the second central portion is 0.4-0.5 mm.

[0012] In some embodiments, the thickness of the first central portion is greater than the thickness of the first edge portion, and the thickness of the third central portion is greater than the thickness of the third edge portion.

[0013] In some embodiments, the thickness of the first central portion is 0.4-0.5 mm, and the thickness of the first edge portion is 0.2-0.3 mm; and / or,

[0014] The thickness of the third central portion is 0.4-0.5 mm, and the thickness of the third edge portion is 0.2-0.3 mm.

[0015] In some embodiments, the thickness of the first central portion is equal to the thickness of the third central portion, and the thickness of the first edge portion is the same as the thickness of the third edge portion.

[0016] In some embodiments, the thickness of the first edge portion is equal to the thickness of the first mounting portion; the thickness of the second edge portion is equal to the thickness of the second mounting portion; and / or, the thickness of the third edge portion is equal to the thickness of the third mounting portion.

[0017] In some embodiments, the ratio of the diameter of the first central portion to the diameter of the diaphragm is (0.65-0.95):1.

[0018] In some embodiments, the second membrane layer is provided with a groove that extends radially along the membrane sheet and passes through the second edge portion and the second mounting portion.

[0019] In some embodiments, the first mounting portion, the second mounting portion, and the third mounting portion are provided with mounting holes corresponding to each other in the thickness direction of the diaphragm.

[0020] The diaphragm compressor of this invention includes the diaphragm described in any of the above embodiments.

[0021] The diaphragm compressor of this invention has a large intake volume under low negative pressure intake conditions. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of a diaphragm compressor according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the structure of the first and third film layers according to an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of the structure of the second film layer in an embodiment of the present invention;

[0025] Figure 4 yes Figure 3 Enlarged view of point A in the middle;

[0026] Figure label:

[0027] Diaphragm compressor 1000

[0028] Diaphragm 100, cylinder block 200, oil-side diaphragm chamber 2001, cylinder head 300, air-side diaphragm chamber 3001;

[0029] First film layer 1, first center portion 11, first edge portion 12, first mounting portion 13, second film layer 2, second center portion 21, second edge portion 22, second mounting portion 23, slot 24, third film layer 3, third center portion 31, third edge portion 32, third mounting portion 33, mounting hole 4. Detailed Implementation

[0030] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0031] like Figures 1 to 4 As shown, the diaphragm compressor 1000 of this embodiment includes a diaphragm 100. The diaphragm 100 includes a first membrane layer 1, a second membrane layer 2, and a third membrane layer 3.

[0032] The first membrane layer 1 includes a first central portion 11, a first edge portion 12 and a first mounting portion 13 distributed sequentially along the radial direction of the membrane 100. The inner side of the first edge portion 12 is connected to the first central portion 11, and the outer side of the first edge portion 12 is connected to the first mounting portion 13.

[0033] The second membrane layer 2 includes a second central portion 21, a second edge portion 22, and a second mounting portion 23, which are sequentially distributed radially along the membrane 100. The second membrane layer 2 is located between the first membrane layer 1 and the third membrane layer 3.

[0034] The third membrane layer 3 includes a third central portion 31, a third edge portion 32, and a third mounting portion 33 sequentially distributed along the radial direction of the membrane 100. The first central portion 11, the second central portion 21, and the third central portion 31 are opposite to each other in the thickness direction of the membrane 100. The first edge portion 12, the second edge portion 22, and the third edge portion 32 are opposite to each other in the thickness direction of the membrane 100. The first mounting portion 13, the second mounting portion 23, and the third mounting portion 33 are opposite to each other in the thickness direction of the membrane 100. The sum of the thicknesses of the first central portion 11, the second central portion 21, and the third central portion 31 is greater than the sum of the thicknesses of the first edge portion 12, the second edge portion 22, and the third edge portion 32.

[0035] In this embodiment of the invention, the first central portion 11, the second central portion 21, and the third central portion 31 of the diaphragm 100 form the central portion of the diaphragm 100; the first edge portion 12, the second edge portion 22, and the third edge portion 32 form the edge portions of the diaphragm 100; and the first mounting portion 13, the second mounting portion 23, and the third mounting portion 33 form the mounting portions of the diaphragm 100. In this embodiment of the invention, the sum of the thicknesses of the first central portion 11, the second central portion 21, and the third central portion 31 is greater than the sum of the thicknesses of the first edge portion 12, the second edge portion 22, and the third edge portion 32; that is, the thickness of the central portion of the diaphragm 100 is greater than the thickness of the edge portions of the diaphragm 100.

[0036] See Figure 1 As shown, the diaphragm compressor 1000 also includes a cylinder body 200, a cylinder head 300, and a piston cylinder (not shown in the figure). The cylinder body 200 has an oil-side groove, and the cylinder head 300 has a gas-side groove. The oil-side groove and the gas-side groove are opposite to each other. A diaphragm 100 is disposed between the cylinder body 200 and the cylinder head 300. The cylinder body 200 and the cylinder head 300 clamp the mounting portion of the diaphragm 100, separating the oil-side groove and the gas-side groove. The wall of the oil-side groove and the side of the diaphragm 100 adjacent to the oil-side groove in the thickness direction define an oil-side diaphragm cavity 2001. The wall of the gas-side groove and the side of the diaphragm 100 adjacent to the gas-side groove in the thickness direction define a gas-side diaphragm cavity 3001. Hydraulic oil is contained in the oil-side diaphragm cavity 2001. In the operating state of the diaphragm compressor 1000, the reciprocating motion of the piston in the piston cylinder drives the diaphragm 100 to reciprocate periodically via the hydraulic oil.

[0037] During one cycle of the piston cylinder, when the piston moves from the lower position to the upper position, the diaphragm 100 deforms and squeezes the gas-side diaphragm 3001, thereby compressing and venting the gas-side diaphragm 3001. When the piston moves from the upper position to the lower position, the diaphragm 100 returns to its flat state and deforms and squeezes the oil-side diaphragm 2001, thereby drawing in air into the gas-side diaphragm 3001.

[0038] During the intake process of the gas-side membrane cavity 3001, when the diaphragm 100 deforms from its flat state to the oil-side membrane cavity 2001, since the thickness of the edge part of the diaphragm 100 is less than that of the center part, the elastic force of the edge part of the diaphragm 100 is greater than that of the center part. The edge part of the diaphragm 100 deforms first and approaches the wall of the oil-side membrane cavity 2001, and the center part of the diaphragm 100 deforms later and approaches the wall of the oil-side membrane cavity 2001. When the diaphragm 100 adheres to the wall of the oil-side membrane cavity 2001, the intake volume of the gas-side membrane cavity 3001 reaches its maximum. During the compression and exhaust process of the gas-side membrane cavity 3001, when the diaphragm 100 deforms from its flat state toward the gas-side membrane cavity 3001, the edge of the diaphragm 100 deforms first and approaches the wall of the gas-side membrane cavity 3001, and the center of the diaphragm 100 deforms later and approaches the wall of the oil-side membrane cavity 2001. When the diaphragm 100 adheres to the wall of the gas-side membrane cavity 3001, the gas-side membrane cavity 3001 completes the exhaust process.

[0039] Compared to diaphragms of moderate thickness in related technologies, the thickness of the central portion of the diaphragm 100 in this embodiment of the invention is greater than the thickness of the edge portion. This results in different elastic forces between the edge and center portions of the diaphragm 100, and the stiffness of the edge portion is less than that of the center portion. Consequently, when the diaphragm deforms, diaphragms of equal thickness exhibit the same deformation trend at all locations. However, in this embodiment of the invention, the deformation trends of the edge and center portions of the diaphragm 100 differ, with the edge portion of the diaphragm 100 exhibiting a different deformation trend. The edge portion of the diaphragm 100 is more easily deformed than the center portion. The deformation amount of the edge portion is greater than that of the center portion, which is more conducive to the deformation of the diaphragm 100 of the embodiment of the present invention towards the oil-side diaphragm cavity 2001 during the intake process of the gas-side diaphragm cavity 3001. This causes the edge portion of the diaphragm 100 to first adhere to the wall surface of the gas-side diaphragm cavity 3001, and the center portion to adhere to the wall surface of the gas-side diaphragm cavity later. This allows the diaphragm 100 to adhere to the wall surface of the oil-side diaphragm cavity 2001, thereby increasing the intake volume of the gas-side diaphragm cavity 3001 under low negative pressure intake conditions.

[0040] Therefore, in this embodiment of the invention, the thickness of the edge portion of the diaphragm 100 is less than the thickness of the center portion, and the stiffness of the edge portion of the diaphragm 100 is less than the stiffness of the center portion, which is more conducive to the deformation of the diaphragm 100 and can increase the intake volume of the gas-side diaphragm cavity 3001 during the intake process under low negative pressure intake conditions.

[0041] To make the solution of this application easier to understand, we will take the example where the thickness direction of the diaphragm 100 is the same as the vertical direction, as shown in the example. Figure 1 As shown.

[0042] The diaphragm compressor 1000 of this invention includes a diaphragm 100, a cylinder body 200, a cylinder head 300, and a piston cylinder.

[0043] The membrane 100 includes a first membrane layer 1, a second membrane layer 2, and a third membrane layer 3. The second membrane layer 2 is located between the first membrane layer 1 and the third membrane layer 3.

[0044] The first membrane layer 1 includes a first central portion 11, a first edge portion 12, and a first mounting portion 13, which are sequentially distributed along the radial direction of the membrane 100. The first central portion 11 is circular, the first edge portion 12 is annular, the first mounting portion 13 is annular, the inner side of the first edge portion 12 is connected to the first central portion 11, and the outer side of the first edge portion 12 is connected to the first mounting portion 13.

[0045] The second membrane layer 2 includes a second central portion 21, a second edge portion 22, and a second mounting portion 23, which are sequentially distributed along the radial direction of the membrane 100. The second central portion 21 is circular, the second edge portion 22 is annular, the second mounting portion 23 is annular, the inner side of the second edge portion 22 is connected to the second central portion 21, and the outer side of the second edge portion 22 is connected to the second mounting portion 23.

[0046] The third membrane layer 3 includes a third central portion 31, a third edge portion 32, and a third mounting portion 33, which are sequentially distributed along the radial direction of the membrane 100. The third central portion 31 is circular, the third edge portion 32 is annular, the third mounting portion 33 is annular, the inner side of the third edge portion 32 is connected to the third central portion 31, and the outer side of the third edge portion 32 is connected to the third mounting portion 33.

[0047] The first central portion 11, the second central portion 21, and the third central portion 31 are opposite each other in the thickness direction of the diaphragm 100. The first edge portion 12, the second edge portion 22, and the third edge portion 32 are opposite each other in the thickness direction of the diaphragm 100. The first mounting portion 13, the second mounting portion 23, and the third mounting portion 33 are opposite each other in the thickness direction of the diaphragm 100. The sum of the thicknesses of the first central portion 11, the second central portion 21, and the third central portion 31 is greater than the sum of the thicknesses of the first edge portion 12, the second edge portion 22, and the third edge portion 32.

[0048] The thickness of the center of the diaphragm 100 is greater than the thickness of the edge of the diaphragm 100, and the stiffness of the center of the diaphragm 100 is greater than the stiffness of the edge of the diaphragm 100. Therefore, the edge of the diaphragm 100 is more prone to deformation than the center. When the diaphragm 100 is deformed toward the oil-side diaphragm cavity 2001, the edge of the diaphragm 100 deforms first, which will drive the center of the diaphragm 100 to move toward the oil-side diaphragm cavity 2001. This makes it easier for the diaphragm 100 to fit against the wall of the oil-side diaphragm cavity 2001, thereby increasing the intake volume of the gas-side diaphragm cavity 3001.

[0049] In some embodiments, if the thickness of the second central portion 21 is equal to the thickness of the second edge portion 22, then the sum of the thicknesses of the first central portion 11 and the third central portion 31 is greater than the sum of the thicknesses of the first edge portion 12 and the third edge portion 32.

[0050] The second film layer 2 is located between the first film layer 1 and the third film layer in the thickness direction of the film 100. The second central part 21 and the second edge part 22 of the second film layer 2 have the same thickness, which facilitates the bonding and connection between the first film 1, the second film 2 and the third film 3, and facilitates the manufacturing and forming of the film 100.

[0051] Specifically, the thickness of the second central part 21 is 0.4-0.5 mm.

[0052] For example, the thickness of the second central part 21 is 0.4 mm, 0.45 mm or 0.5 mm.

[0053] In some embodiments, the thickness of the first central portion 11 is greater than the thickness of the first edge portion 12, and the thickness of the third central portion 31 is greater than the thickness of the third edge portion 32. That is, the diaphragm 100 has thickness variations on both sides in its thickness direction, so that the side of the diaphragm 100 adjacent to the gas-side membrane cavity 3001 has different elastic forces and deformation tendencies, and the side of the diaphragm 100 adjacent to the oil-side membrane cavity 2001 has different elastic forces and deformation tendencies. This makes the deformation of the diaphragm 100 to both sides more regular and the degree of deformation more similar in one motion cycle, which can effectively ensure the stability and operating efficiency of the diaphragm compressor 1000.

[0054] In some embodiments, the thickness of the first central portion 11 is 0.4-0.5 mm, and the thickness of the first edge portion 12 is 0.2-0.3 mm.

[0055] For example, the thickness of the first central portion 11 is 0.4 mm, 0.45 mm or 0.5 mm, and the thickness of the first edge portion 12 is 0.2 mm, 0.25 mm or 0.3 mm.

[0056] The thickness of the third central part 31 is 0.4-0.5 mm, and the thickness of the third edge part 32 is 0.2-0.3 mm.

[0057] For example, the thickness of the third central portion 31 is 0.4 mm, 0.45 mm or 0.5 mm, and the thickness of the third edge portion 32 is 0.2 mm, 0.25 mm or 0.3 mm.

[0058] The first central portion 11, the second central portion 21 and the third central portion 31 of different thicknesses form the central portion of the diaphragm 100 of different thicknesses, and the first edge portion 12, the second edge portion 22 and the third edge portion 32 of different thicknesses form the edge portion of the diaphragm 100 of different thicknesses, so that the stiffness, elastic force and deformation of the diaphragm 100 of different thicknesses are different, thereby adapting to diaphragm compressors with different intake conditions.

[0059] In some embodiments, the thickness of the first central portion 11 is equal to the thickness of the third central portion 31, and the thickness of the first edge portion 12 is the same as the thickness of the third edge portion 32. The first film layer 1 and the third film layer 3 can be manufactured using the same diaphragm, which can improve the versatility and replaceable core of the first film layer 1 and the third film layer 3, thereby reducing the manufacturing cost of the diaphragm 100.

[0060] In some embodiments, the thickness of the first edge portion 12 is equal to the thickness of the first mounting portion 13, which reduces the manufacturing difficulty and cost of the first film layer 1, thereby further reducing the manufacturing difficulty and cost of the diaphragm 100. The thickness of the second edge portion 22 is equal to the thickness of the second mounting portion 23, which reduces the manufacturing difficulty and cost of the second film layer 2, thereby further reducing the manufacturing difficulty and cost of the diaphragm 100. The thickness of the third edge portion 32 is equal to the thickness of the third mounting portion 33, which reduces the manufacturing difficulty and cost of the third film layer 3, thereby further reducing the manufacturing difficulty and cost of the diaphragm 100.

[0061] Furthermore, the second film layer 2, located between the first film layer 1 and the third film layer 3, has the same thickness, which further facilitates the bonding and connection between the first film 1, the second film 2 and the third film 3, and facilitates the manufacturing and forming of the film 100.

[0062] The ratio of the diameter of the first central portion 11 to the diameter of the diaphragm 100 is (0.65-0.95):1. Therefore, the ratio of the central portion of the diaphragm 100 to the diameter of the diaphragm 100 is (0.65-0.95):1. Different thicknesses of the diaphragm 100 result in different stiffness and elastic force. Different thickness ranges (the size range of the central portion of the diaphragm 100) will cause different deformations of the diaphragm 100, thus adapting it to different intake conditions.

[0063] For example, the ratio between the diameter of the central part of the diaphragm and the diameter of the great circle at the edge is 0.65:1, 0.8:1, 0.9:1, or 0.95:1.

[0064] In some embodiments, the second diaphragm layer 2 is provided with a groove 24, which extends radially along the diaphragm 100 and passes through the second edge portion 22 and the second mounting portion 23. The outer side of the groove 24 (that is, the portion corresponding to the second mounting portion 23) is located at the portion of the diaphragm 100 pressed together with the cylinder body 200 and the cylinder head 300. Gas leaking from the gas-side diaphragm cavity 3001 can be discharged through the groove 24, which can be detected by the pressure sensor installed on the cylinder head 300, thereby realizing a damage alarm for the diaphragm 100.

[0065] See Figure 3 As shown, there are four slots 24, which are evenly spaced.

[0066] In some embodiments, the first mounting portion 13, the second mounting portion 23, and the third mounting portion 33 are provided with mounting holes 4 in the thickness direction of the diaphragm. The mounting holes 4 facilitate the positioning and assembly of the first diaphragm layer 1, the second diaphragm layer 2, and the third diaphragm layer 3, and also facilitate the installation of the diaphragm 100 between the cylinder body 200 and the cylinder head 300.

[0067] See Figure 2 and Figure 3 As shown, each of the first mounting part 13, the second mounting part 23 and the third mounting part 33 has two mounting holes 4, and the two mounting holes 4 are symmetrically distributed.

[0068] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0069] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0070] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0071] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0072] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0073] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A diaphragm, characterized in that, include: The first membrane layer (1) includes a first central portion (11), a first edge portion (12) and a first mounting portion (13) distributed sequentially along the radial direction of the membrane. The second membrane layer (2) includes a second central portion (21), a second edge portion (22), and a second mounting portion (23) sequentially distributed radially along the membrane sheet; and The third film layer (3) and the second film layer (2) are located between the first film layer (1) and the third film layer (3). The third film layer (3) includes a third central portion (31), a third edge portion (32) and a third mounting portion (33) distributed sequentially along the radial direction of the film. The first central portion (11), the second central portion (21) and the third central portion (31) are opposite to each other in the thickness direction of the film. The first edge portion (12), the second edge portion (22) and the third edge portion (32) are opposite to each other in the thickness direction of the film. The first mounting portion (13), the second mounting portion (23) and the third mounting portion (33) are opposite to each other in the thickness direction of the film. The sum of the thicknesses of the first central portion (11), the second central portion (21) and the third central portion (31) is greater than the sum of the thicknesses of the first edge portion (12), the second edge portion (22) and the third edge portion (32). The thickness of the first central portion (11) is 0.4-0.5 mm, and the thickness of the first edge portion (12) is 0.2-0.3 mm; The thickness of the third central portion (31) is 0.4-0.5 mm, and the thickness of the third edge portion (32) is 0.2-0.3 mm; The thickness of the second central portion (21) is equal to the thickness of the second edge portion (22); The ratio of the diameter of the first central portion (11) to the diameter of the diaphragm is (0.65-0.95):1; The thickness of the first edge portion (12) is equal to the thickness of the first mounting portion (13); the thickness of the second edge portion (22) is equal to the thickness of the second mounting portion (23); and the thickness of the third edge portion (32) is equal to the thickness of the third mounting portion (33).

2. The diaphragm according to claim 1, characterized in that, The thickness of the first central portion (11) is equal to the thickness of the third central portion (31), and the thickness of the first edge portion (12) is the same as the thickness of the third edge portion (32).

3. The diaphragm according to claim 1, characterized in that, The second membrane layer (2) is provided with a groove that extends radially along the membrane and passes through the second edge portion (22) and the second mounting portion (23).

4. The diaphragm according to claim 1, characterized in that, The first mounting part (13), the second mounting part (23) and the third mounting part (33) are provided with mounting holes in the thickness direction of the diaphragm.

5. A diaphragm compressor, characterized in that, Includes the membrane as described in any one of claims 1 to 4.

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