Compression mechanism of rotary compressor and rotary compressor

Abstract

The present invention discloses a compression mechanism and a rotary compressor of a rotary compressor, including: a first cylinder, a second cylinder, a crankshaft, a first end plate, a second end plate and a partition plate. A first limiting portion is provided on the end face of the intermediate shaft; a second limiting portion cooperating with the first limiting portion is provided on the end face of at least one of the first eccentric portion and the second eccentric portion facing the intermediate shaft; the partition plate has a rotating shaft hole and the intermediate shaft is fitted in the rotating shaft hole. Wherein, the outer diameter of the first rotating shaft is d0, the outer diameter of the second rotating shaft is d1, the outer diameter of the intermediate shaft is d2, the diameter of the rotating shaft hole is d3, the outer diameter of the first eccentric portion is D1, the outer diameter of the second eccentric portion is D2, and d0≤d1<d2≤d3<D1, d0≤d1<d2≤d3<D2. According to the compression mechanism of the rotary compressor of the present invention, the displacement of the rotary compressor can be enlarged, the compression efficiency can be improved, the rigidity of the crankshaft can be increased, and the reliability of torque transmission and the durability reliability are high, and the production efficiency is high.

Description

Technical Field

[0001] The present invention relates to the technical field of compressors, and more particularly, to a compression mechanism of a rotary compressor and a rotary compressor having the compression mechanism of the rotary compressor. Background Art

[0002] In a variable-frequency motor-driven twin-cylinder rotary compressor, since the variation of the compression torque is very small compared to a single-cylinder rotary compressor and it can operate below 30 Hz, it has advantages in terms of air-conditioning comfort, food preservation, and seasonal energy efficiency (APF).

[0003] In a related-art twin-cylinder rotary compressor, if the inner diameter of the partition plate located between the two cylinders is smaller than the outer diameters of the eccentric shaft and the intermediate shaft that are pre-fixed on the crankshaft, the compression mechanism cannot be assembled. Therefore, the inner diameter (d3) of the partition plate ≥ the outer diameter (D) of the eccentric shaft.

[0004] Due to the limitation of this design condition, when the inner diameter of the partition plate increases, the eccentricity of the eccentric shaft becomes smaller, and the decrease in the eccentricity of the eccentric shaft will result in low refrigerating capacity, making it difficult to expand the displacement of the compressor and improve the compression efficiency; moreover, since the outer diameter (d2) of the intermediate shaft connecting the two eccentric shafts cannot be increased, it is difficult to ensure the rigidity of the crankshaft.

[0005] For this reason, the partition plate is usually divided into two parts, or the intermediate shaft is divided into two machined shafts to satisfy the condition that the outer diameter d1 of the rotating shaft < the outer diameter d2 of the intermediate shaft ≤ the inner diameter d3 of the partition plate < the outer diameter D of the eccentric shaft.

[0006] However, it is very difficult to maintain the flatness accuracy of the partition plate divided into two parts, and the intermediate shaft is divided into two parts for machining mainly to improve the strength of the intermediate shaft (only to make d1 < d2), and the practical applications of these two methods are very few. Summary of the Invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a compression mechanism of a rotary compressor, which can expand the displacement of the rotary compressor, improve the compression efficiency, increase the rigidity of the crankshaft, and has high reliability in torque transmission and high durability reliability and high production efficiency.

[0008] The present invention also provides a rotary compressor having the compression mechanism of the rotary compressor.

[0009] The compression mechanism of a rotary compressor according to an embodiment of the first aspect of the present invention includes: a first cylinder and a second cylinder; a crankshaft, the crankshaft being rotatable and including: a first rotating shaft and a second rotating shaft; an intermediate shaft, both ends of the intermediate shaft being connected to the first rotating shaft and the second rotating shaft respectively, and a first limiting portion being provided on an end face of the intermediate shaft; a first eccentric portion and a second eccentric portion, the first eccentric portion being sleeved on the first rotating shaft and being eccentrically arranged, the second eccentric portion being sleeved on the second rotating shaft and being eccentrically arranged, and a second limiting portion cooperating with the first limiting portion being provided on an end face of at least one of the first eccentric portion and the second eccentric portion facing the intermediate shaft, one of the first limiting portion and the second limiting portion being configured as a limiting protrusion and the other being configured as a limiting groove; a first end plate, a second end plate and a partition plate, the first cylinder and the second cylinder being arranged between the first end plate and the second end plate and being separated by the partition plate, the partition plate having a rotating shaft hole and the intermediate shaft being fitted in the rotating shaft hole, the first eccentric portion being arranged in the first cylinder and the second eccentric portion being arranged in the second cylinder, wherein, an outer diameter of the first rotating shaft is d0, an outer diameter of the second rotating shaft is d1, an outer diameter of the intermediate shaft is d2, a diameter of the rotating shaft hole is d3, an outer diameter of the first eccentric portion is D1, an outer diameter of the second eccentric portion is D2, and d0≤d1<d2≤d3<D1, d0≤d1<d2≤d3<D2.

[0010] The compression mechanism of a rotary compressor according to an embodiment of the present invention can increase the displacement of the rotary compressor, improve the compression efficiency, enhance the rigidity of the crankshaft, and has high reliability of torque transmission and high durability reliability as well as high production efficiency.

[0011] In addition, the compression mechanism of a rotary compressor according to an embodiment of the present invention further has the following additional technical features:

[0012] According to some embodiments of the present invention, the first rotating shaft, the second rotating shaft and the intermediate shaft are coaxially arranged, and the first limiting portion is eccentrically arranged relative to the intermediate shaft.

[0013] Furthermore, the first limiting portion is arranged around the central axis of the intermediate shaft and extends along the circumferential direction of the intermediate shaft.

[0014] Advantageously, in a projection plane perpendicular to the central axis of the intermediate shaft, an outer contour line of a projection of the first limiting portion forms an inscribed circle with an outer contour line of a projection of the first rotating shaft or the second rotating shaft.

[0015] Optionally, the first limiting portion is located on a side of the intermediate shaft facing the first eccentric portion, the second limiting portion is provided on an end surface of the first eccentric portion facing the intermediate shaft, and the second eccentric portion is integrally formed on a side of the intermediate shaft facing away from the first eccentric portion.

[0016] In some specific embodiments of the present invention, there are two intermediate shafts and two partition plates. The two intermediate shafts are correspondingly matched with the two partition plates one by one. The crankshaft further includes: an eccentric shaft, the eccentric shaft connecting the two intermediate shafts and having a central axis offset from the central axis of the intermediate shaft. The first limiting portion is located on a side of the intermediate shaft facing away from the eccentric shaft. The compression mechanism further includes: a third cylinder, the third cylinder having a third compression chamber and a third piston that can roll along the inner peripheral wall of the third cylinder. The eccentric shaft is disposed in the third compression chamber and the third piston is sleeved on the outer peripheral wall of the eccentric shaft.

[0017] Advantageously, in a projection plane perpendicular to the central axis of the intermediate shaft, the center of the projection of the first eccentric portion, the center of the projection of the second eccentric portion, and the center of the projection of the eccentric shaft are evenly distributed along the circumferential direction of the intermediate shaft.

[0018] In some embodiments of the present invention, the axial width of at least one of the first eccentric portion and the second eccentric portion is W1, the axial width of the second limiting portion is W1, and W2 = 25% - 30%W1.

[0019] In some specific embodiments of the present invention, the first limiting portion is configured as the limiting protrusion and the second limiting portion is configured as the limiting groove. The end surface of the intermediate shaft is provided with a mounting groove extending along its axial direction. Both ends of the limiting protrusion are respectively fitted in the limiting groove and the mounting groove.

[0020] According to some embodiments of the present invention, a C-shaped retaining ring is provided on an end surface of at least one of the first eccentric portion and the second eccentric portion facing away from the intermediate shaft. The C-shaped retaining ring is sleeved between the first rotating shaft and the first eccentric portion or between the second rotating shaft and the second eccentric portion.

[0021] According to some embodiments of the present invention, the first end plate is provided with a first bearing for cooperating with the first rotating shaft and the second end plate is provided with a second bearing for cooperating with the second rotating shaft.

[0022] According to some embodiments of the present invention, an intermediate bearing is provided between the intermediate shaft and the partition plate, and a shaft end bearing is provided at one end of the second rotating shaft away from the second end plate.

[0023] According to some embodiments of the present invention, the first rotating shaft, the second rotating shaft, and the intermediate shaft are all steel parts, and at least one of the first eccentric part and the second eccentric part is a powder alloy part.

[0024] A rotary compressor according to an embodiment of the second aspect of the present invention includes: a housing provided with a discharge port; a compression mechanism of the rotary compressor according to the embodiment of the first aspect of the present invention, the compression mechanism being provided in the housing; and a drive mechanism provided in the housing and drivingly connected to the crankshaft.

[0025] The rotary compressor according to the embodiment of the present invention uses the compression mechanism of the rotary compressor as described above, has a large displacement, high compression efficiency, good rigidity of the crankshaft, high reliability of torque transmission and high durability reliability, and high production efficiency.

[0026] Additional aspects and advantages of the present invention will be given in part in the following description, will become apparent in part from the following description, or will be understood through the practice of the present invention. Description of the Drawings

[0027] Figure 1 is a longitudinal sectional view of a rotary compressor according to an embodiment of the present invention;

[0028] Figure 2 is a sectional view, front view, left view, and right view of a separated eccentric shaft of a rotary compressor according to an embodiment of the present invention;

[0029] Figure 3 is a left view and a front view of a partial structure of a crankshaft of a rotary compressor according to an embodiment of the present invention;

[0030] Figure 4 is a left view and a front view of a partial structure of a compression mechanism of a rotary compressor according to an embodiment of the present invention;

[0031] Figure 5 is a sectional view of a compression mechanism of a rotary compressor according to an embodiment of the present invention;

[0032] Figure 6 is a sectional view of a compression mechanism of a rotary compressor according to an embodiment of the present invention;

[0033] Figure 7 is a schematic diagram of a partial structure of a crankshaft of a rotary compressor according to a first alternative embodiment of the present invention;

[0034] Figure 8 is a partial sectional view of a compression mechanism of a rotary compressor according to a first alternative embodiment of the present invention;

[0035] Figure 9It is a cross-sectional view of the compression mechanism of a rotary compressor according to a first alternative embodiment of the present invention;

[0036] Figure 10 It is a left view and a front view of a partial structure of the crankshaft of a rotary compressor according to a second alternative embodiment of the present invention;

[0037] Figure 11 It is a cross-sectional view of the compression mechanism of a rotary compressor according to a second alternative embodiment of the present invention;

[0038] Figure 12 It is a longitudinal cross-sectional view of a rotary compressor according to a third alternative embodiment of the present invention;

[0039] Figure 13 It is a schematic diagram of a partial structure of the crankshaft of a rotary compressor according to a third alternative embodiment of the present invention;

[0040] Figure 14 It is a partial cross-sectional view of the compression mechanism of a rotary compressor according to a fourth alternative embodiment of the present invention;

[0041] Figure 15 It is a partial cross-sectional view of the compression mechanism of a rotary compressor according to a fifth alternative embodiment of the present invention.

[0042] Reference numerals:

[0043] First double-cylinder rotary compressor 102, second double-cylinder rotary compressor 103,

[0044] Housing 2, electric motor 3, stator 3a, rotor 3b,

[0045] First compression mechanism section 4A, second compression mechanism section 4B, third compression mechanism section 4C,

[0046] First crankshaft 10A, second crankshaft 10B, third crankshaft 10C, first rotating shaft 11, second rotating shaft 12, intermediate shaft 13, circular protrusion 13a,

[0047] First end plate 5, first bearing 5a, second end plate 6, second bearing 6a, partition plate 7, rotating shaft hole 7a,

[0048] First cylinder 8, first compression chamber 8a, second cylinder 9, second compression chamber 9a, third cylinder 14,

[0049] Separation eccentric shaft 15, shaft hole 15a, circular groove 15b, thrust protrusion 15c, ejector pin 15d,

[0050] Upper end shaft 16, fixed eccentric shaft 20, rolling piston 21, intermediate bearing 22, shaft end bearing 23, C-shaped retaining ring 25, upper oil vane cylinder 27, suction pipe 30, exhaust pipe 31, bearing cylinder 32. Detailed implementation mode

[0051] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation to the present invention.

[0052] The compression mechanism of a rotary compressor according to an embodiment of the first aspect of the present invention will be described below with reference to the drawings.

[0053] Optionally, the rotary compressor may be a vertical compressor. In the following description of the present application, the rotary compressor is taken as an example of a vertical compressor for illustration. Of course, those skilled in the art can understand that the rotary compressor may also be a horizontal compressor (not shown in the figure). Here, it should be noted that a "vertical compressor" can be understood as a compressor in which the central axis of the cylinder of the compression mechanism of the rotary compressor is perpendicular to the installation surface of the rotary compressor. For example, as Figure 1 shown, the central axis of the cylinder extends in the vertical direction. Correspondingly, a "horizontal compressor" can be understood as a compressor in which the central axis of the cylinder is parallel to the installation surface of the rotary compressor.

[0054] As Figures 1 - 15 shown, the compression mechanism of the rotary compressor according to an embodiment of the present invention includes: a first cylinder 8, a second cylinder 9, a crankshaft, a first end plate 5, a second end plate 6, and a partition plate 7.

[0055] Specifically, the first cylinder 8 and the second cylinder 9 are provided between the first end plate 5 and the second end plate 6 and separated by the partition plate 7, that is, the first end plate 5, the first cylinder 8, the partition plate 7, the second cylinder 9, and the second end plate 6 are arranged in sequence in the up-down direction. The first cylinder 8 has a first compression chamber 8a and is provided with a first piston that can roll along the inner peripheral wall of the first cylinder 8. The second cylinder 9 has a second compression chamber 9a and is provided with a second piston that can roll along the inner peripheral wall of the second cylinder 9.

[0056] The crankshaft is rotatable and includes a first rotating shaft 11, a second rotating shaft 12, an intermediate shaft 13, a first eccentric portion, and a second eccentric portion. The two ends of the intermediate shaft 13 are respectively connected to the first rotating shaft 11 and the second rotating shaft 12. The intermediate shaft 13 is provided with a first limiting portion, and the first limiting portion is configured as a limiting protrusion extending out of its end face along the axial direction of the intermediate shaft 13 (such as the up and down direction). The first eccentric portion is sleeved on the first rotating shaft 11, and the first eccentric portion is eccentrically arranged, that is, the central axis of the first eccentric portion deviates from the central axis of the first rotating shaft 11; the second eccentric portion is sleeved on the second rotating shaft 12, and the second eccentric portion is eccentrically arranged, that is, the central axis of the second eccentric portion deviates from the central axis of the second rotating shaft 12.

[0057] At least one of the end faces of the first eccentric portion and the second eccentric portion facing the intermediate shaft 13 is provided with a second limiting portion, and the first limiting portion is fitted in the second limiting portion. The second limiting portion is configured as a limiting groove. Here, "at least one" means that the upper end face of the first eccentric portion is provided with a second limiting portion, and the first limiting portion extends downward out of the lower end face of the intermediate shaft 13, so that the first eccentric portion and the first rotating shaft 11 can be separated; or, the lower end face of the second eccentric portion is provided with a second limiting portion, and the first limiting portion extends upward out of the upper end face of the intermediate shaft 13, so that the second eccentric portion and the second rotating shaft 12 can be separated; or, the upper end face of the first eccentric portion is provided with a second limiting portion, and the first limiting portion extends downward out of the lower end face of the intermediate shaft 13, and the lower end face of the second eccentric portion is provided with a second limiting portion, and the first limiting portion extends upward out of the upper end face of the intermediate shaft 13, so that the first eccentric portion and the first rotating shaft 11 can be separated and the second eccentric portion and the second rotating shaft 12 can be separated.

[0058] It can be understood that it can also be that the first limiting portion is configured as a limiting groove and the second limiting portion is configured as a limiting protrusion, as long as it is ensured that the first limiting portion and the second limiting portion can be fitted together. The present invention does not make special limitations on this. It should be noted that the embodiments given in this application are only described with the first limiting portion as a limiting protrusion and the second limiting portion as a limiting groove as an example, and should not be construed as a limitation to the present invention.

[0059] The partition plate 7 has a rotating shaft hole 7a and the intermediate shaft 13 is fitted in the rotating shaft hole 7a. The first eccentric portion is arranged in the first compression chamber 8a and the first piston is sleeved on the outer peripheral wall of the first eccentric portion. The second eccentric portion is arranged in the second compression chamber 9a and the second piston is sleeved on the outer peripheral wall of the second eccentric portion.

[0060] Among them, the outer diameter of the first rotating shaft 11 is d0, the outer diameter of the second rotating shaft 12 is d1, the outer diameter of the intermediate shaft 13 is d2, the diameter of the rotating shaft hole 7a is d3, the outer diameter of the first eccentric portion is D1, and the outer diameter of the second eccentric portion is D2. d0≤d1<d2≤d3<D1, d0≤d1<d2≤d3<D2.

[0061] According to the compression mechanism of the rotary compressor according to an embodiment of the present invention, by means of the cooperation between the first limiting portion axially extending from the intermediate shaft 13 and the second limiting portion provided on the end face, torque connection is achieved, so that the torque of the crankshaft becomes the torque of the intermediate shaft 13 after being transmitted to the intermediate shaft 13, and then is transmitted to the first eccentric portion and the second eccentric portion through the intermediate shaft 13 to become the torque of the first eccentric portion and the second eccentric portion. Moreover, the reliability of torque transmission and the durability reliability are optimized; since d1 < d2 ≤ d3 < D1 and d1 < d2 ≤ d3 < D2 are satisfied, the refrigerating capacity of the rotary compressor and the displacement of each cylinder can be enlarged, thereby achieving an increase in the displacement of the rotary compressor, an improvement in the compression efficiency, and an improvement in the rigidity of the crankshaft.

[0062] Meanwhile, since the above torque connection structure is composed of a concave-convex matching structure, these structures can be machined by an automatic lathe, with high machining accuracy and easy assembly, thus improving the production efficiency. In addition, since the conventionally integrally formed crankshaft is divided into multiple parts, it is relatively easy to introduce steel pipes, powder alloys, and forging processes into the crankshaft.

[0063] According to some embodiments of the present invention, as Figures 1 - 15 shown, the first rotating shaft 11, the second rotating shaft 12, and the intermediate shaft 13 are coaxially arranged, that is, the central axis of the first rotating shaft 11, the central axis of the second rotating shaft 12, and the central axis of the intermediate shaft 13 coincide, thus facilitating the manufacturing and shaping of the crankshaft. Among them, the first limiting portion is eccentrically arranged relative to the intermediate shaft 13, that is, the center line of the first limiting portion deviates from the central axis of the intermediate shaft 13 to ensure the eccentric arrangement of the first eccentric portion or the second eccentric portion that cooperates with the first limiting portion.

[0064] Furthermore, as Figures 1 - 13 and Figure 15 shown, the first limiting portion is arranged around the central axis of the intermediate shaft 13, and the first limiting portion extends along the circumferential direction of the intermediate shaft 13, thereby improving the reliability and durability of torque transmission. In order to simplify the structures of the first limiting portion and the second limiting portion and facilitate manufacturing and shaping, the first limiting portion and the second limiting portion can be respectively designed to be circular, that is, the first limiting portion is configured as a circular protrusion 13a, and at least one of the first eccentric portion and the second eccentric portion is a split eccentric shaft 15, and the second limiting portion on the split eccentric shaft 15 is configured as a circular groove 15b.

[0065] Advantageously, as Figure 2 and Figure 4As shown, within the projection plane perpendicular to the central axis of the intermediate shaft 13, the outer contour line of the projection of the first limiting portion is inscribed with the outer contour line of the projection of the first rotating shaft 11 or the second rotating shaft 12, facilitating processing. For example, the separating eccentric shaft 15 has a shaft hole 15a, and the central axis of the circular groove 15b is offset from the central axis of the shaft hole 15a. Within the projection plane perpendicular to the central axis of the shaft hole 15a, the contour line of the projection of the shaft hole 15a is inscribed with the contour line of the projection of the circular groove 15b.

[0066] Optionally, as Figure 7 and Figure 8 shown, the first limiting portion is located on one side (i.e., the lower side) of the intermediate shaft 13 facing the first eccentric portion. The end face (i.e., the upper end face) of the first eccentric portion facing the intermediate shaft 13 is provided with a second limiting portion, and the second eccentric portion is integrally formed on the side of the intermediate shaft 13 opposite to the first eccentric portion (i.e., the upper side). For example, the first eccentric portion is configured as a separating eccentric shaft 15, the second eccentric portion is configured as a fixed eccentric shaft 20, the first rotating shaft 11, the second rotating shaft 12, the intermediate shaft 13, the first limiting portion and the fixed eccentric shaft 20 are integrally formed. During assembly, first insert the first rotating shaft 11 into the first cylinder 8, and then assemble the separating eccentric shaft 15 onto the first rotating shaft 11 and the first limiting portion.

[0067] In some specific embodiments of the present invention, as Figure 10 and Figure 11 shown, both the intermediate shaft 13 and the partition 7 are two, and the two intermediate shafts 13 are in one-to-one correspondence and cooperation with the two partitions 7. The crankshaft further includes an eccentric shaft that connects the two intermediate shafts 13, and the central axis of the eccentric shaft is offset from the central axis of the intermediate shaft 13. The first limiting portions are two and are respectively located on the sides of the two intermediate shafts 13 opposite to the eccentric shaft. The compression mechanism further includes a third cylinder 14 that has a third compression chamber and is provided with a third piston that can roll along the inner peripheral wall of the third cylinder 14. The eccentric shaft is provided in the third compression chamber and the third piston is sleeved on the outer peripheral wall of the eccentric shaft. The first piston, the second piston, and the third piston are all rolling pistons 21. For example, the eccentric shaft is a fixed eccentric shaft 20, and the first first limiting portion and the second first limiting portion are both separating eccentric shafts 15 and are respectively located on the upper and lower sides of the fixed eccentric shaft 20.

[0068] Advantageously, as Figure 11 shown, within the projection plane perpendicular to the central axis of the intermediate shaft 13, the centers of the projections of the first eccentric portion, the centers of the projections of the second eccentric portion, and the center of the projection of the eccentric shaft are evenly distributed along the circumferential direction of the intermediate shaft 13, that is, the angles between the projections of the first eccentric portion, the projections of the second eccentric portion, and the projection of the eccentric shaft are 120°, to balance the compression torque.

[0069] In some embodiments of the present invention, as Figure 2As shown, the axial width of at least one of the first eccentric part and the second eccentric part (i.e., the separating eccentric shaft 15) is W1, the axial width of the second limiting part is W1, and W2 = 25% - 30%W1, so that the contact area can be controlled within a reasonable range and the friction can be reduced.

[0070] In some specific embodiments of the present invention, as Figure 14 shown, the end face of the intermediate shaft 13 is provided with a mounting groove extending along its axial direction, and both ends of the first limiting part are respectively fitted in the second limiting part and the mounting groove, so as to realize the connection of the separating eccentric shaft 15 in a simpler form, which is applicable to a small double-cylinder rotary compressor with a lower operating pressure and a smaller crankshaft torque. For example, the first limiting part is an ejector pin 15d, and the ejector pin 15d assembles the intermediate shaft 13 and the separating eccentric shaft 15 together.

[0071] According to some embodiments of the present invention, as Figure 15 shown, a C-shaped stop ring 25 is provided on the end face of at least one of the first eccentric part and the second eccentric part facing away from the intermediate shaft 13, and the C-shaped stop ring 25 is sleeved between the first rotating shaft 11 and the first eccentric part or between the second rotating shaft 12 and the second eccentric part, so as to fix the separating eccentric shaft 15. Thus, through the fixed connection of the C-shaped stop ring 25, the intermediate shaft 13 and the separating eccentric shaft 15, the subsequent centering assembly will be easier.

[0072] For example, the lower end face of the first eccentric part has a thrust protrusion 15c, and the thrust protrusion 15c serves as a thrust surface sliding on the end face of the first end plate 5, and the C-shaped stop ring 25 is arranged in the thrust protrusion 15c. In addition, in this embodiment, the outer diameter d0 of the first rotating shaft 11 < the outer diameter d1 of the second rotating shaft 12.

[0073] According to some embodiments of the present invention, as Figure 1 and Figure 5 shown, the first end plate 5 is provided with a first bearing 5a cooperating with the first rotating shaft 11 and the second end plate 6 is provided with a second bearing 6a cooperating with the second rotating shaft 12 to support the load of the crankshaft.

[0074] According to some embodiments of the present invention, as Figure 12 shown, an intermediate bearing 22 is provided between the intermediate shaft 13 and the partition plate 7, and a shaft end bearing 23 is provided at one end (i.e., the upper end) of the second rotating shaft 12 away from the second end plate 6, so that the structures of the first end plate 5 and the second end plate 6 can be simplified.

[0075] According to some embodiments of the present invention, the first rotating shaft 11, the second rotating shaft 12 and the intermediate shaft 13 are all made of steel, and at least one of the first eccentric part and the second eccentric part (i.e., the separating eccentric shaft 15) is suitable for powder molding. For example, the separating eccentric shaft 15 is a powder alloy part.

[0076] A rotary compressor according to an embodiment of the second aspect of the present invention includes: a housing 2, a compression mechanism, and a drive mechanism of the rotary compressor according to the embodiment of the first aspect of the present invention.

[0077] Specifically, the housing 2 is provided with a discharge port. Both the compression mechanism and the drive mechanism are disposed inside the housing 2, and the drive mechanism is in transmission connection with the crankshaft. For example, the drive mechanism is an electric motor 3.

[0078] The rotary compressor according to the embodiment of the present invention utilizes the compression mechanism of the rotary compressor as described above, has a large displacement, high compression efficiency, good rigidity of the crankshaft, high reliability of torque transmission and durability reliability, and high production efficiency.

[0079] The rotary compressor according to different embodiments of the present invention will be described below with reference to the accompanying drawings.

[0080] Embodiment 1

[0081] Figure 1 A longitudinal sectional view is shown when the rotary compressor is a first double-cylinder rotary compressor 102, the compression mechanism is a compression mechanism portion 4A, and the crankshaft is a crankshaft 10A.

[0082] Specifically, the electric motor 3 and the compression mechanism portion 4A are fixed on the inner periphery of the closed housing 2. The electric motor 3 is composed of a stator 3a fixed on the closed housing 2 and a rotor 3b fixed on the crankshaft 10A, and rotationally drives the compression mechanism portion 4A.

[0083] The compression mechanism portion 4A is composed of the following components: a first cylinder 8 and a second cylinder 9 fixed on the inner periphery of the closed housing 2, a partition plate 7 between the two cylinders, a first end plate 5 and a second end plate 6 for sealing the open ends of the first compression chamber 8a and the second compression chamber 9a in the cylinders, a first rotating shaft 11 and a second rotating shaft 12 slidably engaged with bearings at the centers of these components, two separate eccentric shafts 15 fixed on the first rotating shaft 11 and the second rotating shaft 12, a rolling piston 21 slidably engaged on the outer periphery of these separate eccentric shafts 15 and eccentrically rotating, etc. In addition, an oil supply vane cylinder 27 is provided at the shaft end of the first rotating shaft 11.

[0084] In the above structure of the compression mechanism portion 4A, before fixing the first end plate 5 and the second end plate 6 to the first cylinder 8 and the second cylinder 9, the two separate eccentric shafts 15 are respectively inserted from the shaft ends of the first rotating shaft 11 and the second rotating shaft 12, and the circular grooves 15b on the end faces of the separate eccentric shafts 15 are inserted into the circular protrusions 13a provided at both ends of the intermediate shaft 13.

[0085] Since the circular groove 15b and the circular protrusion 13a are eccentric by an eccentricity e1 with respect to the rotation center line 10a of the crankshaft 10A, the two separated eccentric shafts 15 eccentrically rotate by an eccentricity e2 according to the torque of the crankshaft 10A. Similarly, the two rolling pistons 21 are opposed to each other at an angle of 180° and eccentrically rotate in the first compression chamber 8a and the second compression chamber 9a.

[0086] The low-pressure gas flowing in from the two intake pipes 30 respectively connected to the first cylinder 8 and the second cylinder 9 flows into the first compression chamber 8a and the second compression chamber 9a, and the compressed high-pressure gas is discharged from the exhaust pipe 31 via the mufflers and the electric motor 3 on the first end plate 5 and the second end plate 6. After that, it circulates once in the refrigeration cycle device and then returns to the two intake pipes 30.

[0087] As Figure 2 shown, the separated eccentric shaft 15 is characterized in that a circular groove 15b is provided on its end face, and a shaft hole 15a is formed in the circular groove 15b. The circular groove 15b is eccentric by an eccentricity e1 with respect to the shaft hole 15a, and the outer diameter D of the separated eccentric shaft 15 is eccentric by an eccentricity e2 with respect to the central axis of the shaft hole 15a. That is to say, e2 is also the eccentricity of the rolling piston 21 revolving in the compression chamber. In addition, the inner diameter circle of the shaft hole 15a is not outside the circle of the circular groove 15b. Figure 2 The inner diameter end of the shaft hole 15 shown is consistent with the circular diameter of the eccentric circular groove 15b.

[0088] The eccentricity e1 plays an important role in causing the separated eccentric shaft 15 to revolve by the torque of the crankshaft 10A via the circular protrusion 13a of the intermediate shaft 13. The outer diameter D of the separated eccentric shaft 15 is the cylindrical surface on which the inner diameter of the rolling piston 21 slides, and the thrust protrusion 15c is the thrust surface that slides on the plane of the first end plate 5.

[0089] Since the shaft hole 15a does not slide on the outer diameters of the first rotating shaft 11 and the second rotating shaft 12, the gap between them should be reduced as much as possible, and this gap is 1 / 2000 or less of the outer diameter of the corresponding shaft. For example, when the outer diameter of the first rotating shaft 11 is 16 mm, the gap between the shaft hole 15a and the first rotating shaft 11 is 8 μm or less, and moreover, the gap when the separated eccentric shaft 15 is shrink-fitted and assembled on the first rotating shaft 11 should be made even smaller. Among them, the depth of the circular groove 15b is W2, accounting for 25-30% of the width W1 of the separated eccentric shaft 15.

[0090] In addition, the shape of the separated eccentric shaft 15 is cylindrical and can be machined by an automatic lathe. After that, the shaft hole 15a and the outer diameter of the separated eccentric shaft 15 need to be ground. The separated eccentric shaft 15 can use the same material as the crankshaft - spheroidal graphite cast iron (such as FCD500, etc.). Preferably, since the shape of the separated eccentric shaft 15 is suitable for powder molding, powder alloy can also be used.

[0091] AsFigure 4 As shown, centering is performed on the first compression chamber 8a of the first cylinder 8 and the second compression chamber 9a of the second cylinder 9, and the above two cylinders are fixed on the upper and lower surfaces of the partition plate 7 by pins 24 on the partition plate 7. Next, the shaft end of the first rotary shaft 11 is inserted into the rotary shaft hole 7a. Then, the separating eccentric shafts 15 are inserted into the shaft ends of the second rotary shaft 12 and the first rotary shaft 11 respectively. After inserting the circular groove 15b of the separating eccentric shaft 15 into the circular protrusion 13a, the assembly of the two opposing separating eccentric shafts 15 is completed. Among them, the clearance between the intermediate shaft 13 and the rotary shaft hole 7a is approximately 0.2 mm.

[0092] After the above structure of the compression mechanism portion 4A is assembled, two rolling pistons 21 are respectively inserted onto the two separating eccentric shafts 15 and the sliders (not shown in the figure) are assembled. Then, the second end plate 6 is fixed to the second cylinder 9 with screws, and centering of the second compression chamber 9a and the second rotary shaft 12 is performed. Next, the first end plate 5 is inserted onto the first rotary shaft 11 and fixed to the first cylinder 8 with screws, and centering of the first compression chamber 8a and the first rotary shaft 11 is performed. Thus, the compression mechanism portion 4A shown above is assembled. Figure 5 As shown.

[0093] It should be noted that the torque of the crankshaft 10A that slides and mates with the first bearing 5a and the second bearing 6a respectively provided on the first end plate 5 and the second end plate 6 is transmitted to the two separating eccentric shafts 15 through the eccentricity e1 of the two circular protrusions 13a on the intermediate shaft 13, and the two separating eccentric shafts 15 and the two rolling pistons 21 perform eccentric rotation.

[0094] Since the two separating eccentric shafts 15 are respectively fixed to the first rotary shaft 11 and the second rotary shaft 12, the eccentricity e2 and the rotational accuracy of the outer diameter of the separating eccentric shaft 15 are determined according to Figure 2 the shape accuracy of the separating eccentric shaft 15 shown and the fixing clearance between the separating eccentric shaft 15 and the first rotary shaft 11 and the second rotary shaft 12, and have nothing to do with the accuracy of the eccentricity e1 of the torque transmission means. However, the mating clearance between the circular protrusion 13a and the circular groove 15b affects the relative angle (180°) of the two separating eccentric shafts 15.

[0095] Next, the up and down movement of the crankshaft 10A caused by the load of the crankshaft 10A and the magnetic force variation of the rotor 3b will be described.

[0096] As Figure 5 shown, the downward load is docked with the first end plate 5 through the thrust protrusion 15c of the separating eccentric shaft 15, and the upward load is limited by the limiter formed by the second end plate 6 as the thrust protrusion 15c of the separating eccentric shaft 15, thereby restricting the up and down movement of the crankshaft 10A.

[0097] Next, as Figure 6 shown, the outer diameters of the first rotating shaft 11 and the second rotating shaft 12 are both d1, the outer diameter of the intermediate shaft 13 is d2, the diameter of the rotating shaft hole 7a is d3, and the outer diameter of the separating eccentric shaft 15 is D. Then, d1 < d2 ≤ d3 < D holds. By assembling the separating eccentric shaft 15, the diameter reduction of the partition plate 7 and the increase of the outer diameter of the intermediate shaft 13 can be achieved.

[0098] Since d3 < D, the minimum clearance m between the inner diameter of the rotating shaft hole 7a and the outer diameter of the rolling piston 21 increases. The high-pressure side gas of the partition plate 7 does not leak to the low-pressure sides of the first compression chamber 8a and the second compression chamber 9a. Therefore, the re-expansion loss of the high-pressure gas can be improved. At the same time, since d1 < d2, the rigidity of the intermediate shaft 13 is improved, and the deformation of the intermediate shaft 13 caused by the compression loads alternately generated in the first compression chamber 8a and the second compression chamber 9a by the rolling piston 21 is greatly improved.

[0099] In addition, d3 < D enables the eccentricity e2 of the separating eccentric shaft 15 to increase, and the displacement can be increased without expanding the inner diameter of the compressor. That is, not only can a large refrigerating capacity be ensured in the small cylinder compression chamber, but it is also effective in improving the compression efficiency. In addition, it is also beneficial to the enlargement of the twin-cylinder rotary compressor.

[0100] As Figure 3 shown, the crankshaft 10A is a rod-shaped shaft, and the material selection and manufacturing method of the crankshaft 10A are very extensive. For example, the crankshaft 10A can be a cast iron part, or the crankshaft 10A can be an SCM steel bar (i.e., chromium-molybdenum steel) with wear resistance and high rigidity and can be wear-resistant treated, or the crankshaft 10A can adopt the shaping method of forging the intermediate shaft 13. Thus, the improvement of the durability reliability and production efficiency of the crankshaft 10A can be achieved simultaneously.

[0101] Embodiment 2

[0102] This embodiment relates to a twin-cylinder rotary compressor using a separating eccentric shaft 15 and a fixed eccentric shaft 20 in combination.

[0103] As Figure 7 shown, the fixed eccentric shaft 20 is provided on the second rotating shaft 12 of the crankshaft 10B, the separating eccentric shaft 15 is assembled on the first rotating shaft 11, and the intermediate shaft 13 is only equipped with a circular protrusion 13a on the side facing the first rotating shaft 11.

[0104] As Figure 8As shown, after the partition plate 7, the first cylinder 8, and the second cylinder 9 are assembled for core alignment, the first rotating shaft 11 of the crankshaft 10B is inserted into the rotating shaft hole 7a. At this time, the intermediate shaft 13a is stationary in the rotating shaft hole 7a. Starting from the shaft end of the first rotating shaft 11, the separating eccentric shaft 15 is inserted, and the circular groove 15b is fitted onto the circular protrusion 13a. After that, partial assembly is completed.

[0105] Then, through the same process as in Embodiment 1, the assembly of the compression mechanism portion 4B shown is completed. Figure 9 Embodiment 2 gives an example that even if one of the first eccentric portion and the second eccentric portion is used as the fixed eccentric shaft 20, the assembly of the compression mechanism portion 4B can be completed in the same manner as in Embodiment 1. Additionally, d1 < d2 ≤ d3 < D also holds.

[0106] Embodiment 3

[0107] As Figure 10 shown, there is a fixed eccentric shaft 20 between the first rotating shaft 11 and the second rotating shaft 12 of the crankshaft 10C of the three-cylinder rotary compressor. The intermediate shaft 13 and the circular protrusion 13a are connected to both sides of the fixed eccentric shaft 20. In order to average the compression torque, in the projection plane perpendicular to the crankshaft 10C, the angle between the two separating eccentric shafts 15 and the fixed eccentric shaft 20 of the three-cylinder rotary compressor is 120°, and the centers of the above three eccentric shafts are the vertices of an equilateral triangle and rotate unidirectionally respectively.

[0108] Thus, the assembly sequence of the two separating eccentric shafts 15 of the crankshaft 10C and the two partition plates 7 is as follows:

[0109] First, the rolling piston 21 is inserted into the fixed eccentric shaft 20, and the second compression chamber of the third cylinder 14 is pressed onto the outer circumference of the rolling piston 21. Next, the two partition plates 7 are fixed at predetermined positions on both side planes of the third cylinder 14.

[0110] Then, the separating eccentric shafts 15 are respectively inserted into the shaft ends of the second rotating shaft 12 and the first rotating shaft 11, and the circular groove 15b is fitted onto the circular protrusion 13a. Then, the first cylinder 8 and the second cylinder 9 are respectively fixed at predetermined positions on the two already assembled partition plates 7 and core alignment with the third cylinder 14 is performed. Next, after the rolling piston 21 is inserted onto the outer circumferences of the two assembled separating eccentric shafts 15, the first end plate 5 and the second end plate 6 are respectively fixed to the first cylinder 8 and the second cylinder 9 with screws. After that, core alignment of the first end plate 5, the second end plate 6, the first rotating shaft 11, and the second rotating shaft 12 is performed.

[0111] Figure 11The longitudinal sectional view of the assembled compression mechanism section 4C is shown. Among them, the exhaust holes of the first cylinder 8 and the second cylinder 9 are respectively arranged on the first end plate 5 and the second end plate 6, and the exhaust hole of the third cylinder 14 is installed on the muffler built in any one of the two partition plates 7.

[0112] Since Figure 10 the crankshaft 10C in connects the two intermediate shafts 13 with the fixed eccentric shaft 20, greatly improving the rigidity of the crankshaft. In addition, in Embodiment 3, d1 < d2 ≤ d3 < D is also achieved.

[0113] Embodiment 4

[0114] Figure 12 In the second double-cylinder rotary compressor 103 shown in , by applying the feature that the outer diameter d2 of the intermediate shaft 13 > the outer diameters d1 of the first rotating shaft 11 and the second rotating shaft 12, the intermediate shaft 13 of the crankshaft 10D is slidably fitted with the intermediate bearing 22 fitted at the center of the partition plate 7, and the upper end shaft 16 of the second rotating shaft 12 is slidably fitted with the shaft end bearing 23 fitted at the center of the bearing cylinder 32, so that the first bearing 5a and the second bearing 6a adopted in Embodiment 1 etc. can be omitted.

[0115] Thus, the intermediate shaft 13 supports the compression load generated on the two rolling pistons 21 in the first cylinder 8 and the second cylinder 9 and is slidably fitted with the intermediate bearing 22. The upper end shaft 16 supports the vibration load of the second rotating shaft 12 having the rotor 3b and is slidably fitted with the shaft end bearing 23. In addition, if the intermediate bearing 22 and the shaft end bearing 23 adopt bushings and shaft end bearings, the reliability of the bearings will be improved and the rotational speed of the crankshaft 10D will be increased significantly.

[0116] Other configurations and operations of the rotary compressor according to the embodiments of the present invention are known to those of ordinary skill in the art and will not be described in detail here.

[0117] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "upper", "lower", "vertical", "inner", "outer", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0118] In addition, 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 quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality of" is two or more than two.

[0119] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "mounted", "connected" and "coupled" shall be construed in a broad sense. For example, it may be a fixed connection, a detachable connection or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, or the internal communication of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention may be understood according to specific circumstances.

[0120] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "specific embodiments", "examples" or "some examples", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0121] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. A compression mechanism of a rotary compressor, characterized in that, it includes: a first cylinder and a second cylinder; a crankshaft, the crankshaft is rotatable and includes: a first rotating shaft and a second rotating shaft; an intermediate shaft, both ends of the intermediate shaft are respectively connected to the first rotating shaft and the second rotating shaft, and a first limiting portion is provided on the end face of the intermediate shaft; a first eccentric portion and a second eccentric portion, the first eccentric portion is sleeved on the first rotating shaft and is eccentrically arranged, the second eccentric portion is sleeved on the second rotating shaft and is eccentrically arranged, and at least one of the end faces of the first eccentric portion and the second eccentric portion facing the intermediate shaft is provided with a second limiting portion that cooperates with the first limiting portion, and one of the first limiting portion and the second limiting portion is configured as a limiting protrusion and the other is configured as a limiting groove; a first end plate, a second end plate and a partition plate, the first cylinder and the second cylinder are arranged between the first end plate and the second end plate and are separated by the partition plate, the partition plate has a rotating shaft hole and the intermediate shaft is fitted in the rotating shaft hole, the first eccentric portion is arranged in the first cylinder and the second eccentric portion is arranged in the second cylinder, wherein, the outer diameter of the first rotating shaft is d0, the outer diameter of the second rotating shaft is d1, the outer diameter of the intermediate shaft is d2, the diameter of the rotating shaft hole is d3, the outer diameter of the first eccentric portion is D1, the outer diameter of the second eccentric portion is D2, d0≤d1<d2≤d3<D1, d0≤d1<d2≤d3<D2; the first rotating shaft, the second rotating shaft and the intermediate shaft are coaxially arranged, and the first limiting portion is eccentrically arranged relative to the intermediate shaft; the first limiting portion is arranged around the central axis of the intermediate shaft and extends along the circumferential direction of the intermediate shaft; in a projection plane perpendicular to the central axis of the intermediate shaft, the outer contour line of the projection of the first limiting portion forms an inscribed circle with the outer contour line of the projection of the first rotating shaft or the second rotating shaft.

2. The compression mechanism of the rotary compressor according to claim 1, characterized in that, the first limiting portion is located on one side of the intermediate shaft facing the first eccentric portion, the end face of the first eccentric portion facing the intermediate shaft is provided with the second limiting portion, and the second eccentric portion is integrally formed on the side of the intermediate shaft opposite to the first eccentric portion.

3. The compression mechanism of the rotary compressor according to claim 1, characterized in that, both the intermediate shaft and the partition plate are two, and the two intermediate shafts are respectively and correspondingly fitted with the two partition plates, and the crankshaft further includes: an eccentric shaft, the eccentric shaft connects the two intermediate shafts and the central axis deviates from the central axis of the intermediate shaft, the first limiting portion is located on the side of the intermediate shaft opposite to the eccentric shaft, and the compression mechanism further includes: a third cylinder, a third compression chamber is provided in the third cylinder and a third piston that can roll along the inner peripheral wall of the third cylinder is provided, the eccentric shaft is arranged in the third compression chamber and the third piston is sleeved on the outer peripheral wall of the eccentric shaft.

4. The compression mechanism of the rotary compressor according to claim 3, It is characterized in that in the projection plane perpendicular to the central axis of the middle shaft, the centers of the projections of the first eccentric part, the centers of the projections of the second eccentric part and the center of the projection of the eccentric shaft are evenly distributed along the circumferential direction of the middle shaft.

5. The compression mechanism of the rotary compressor according to claim 1, It is characterized in that the axial width of at least one of the first eccentric part and the second eccentric part is W1, the axial width of the second limiting part is W2, and W2 = 25% - 30%W1.

6. The compression mechanism of the rotary compressor according to claim 1, It is characterized in that the first limiting part is configured as the limiting protrusion and the second limiting part is configured as the limiting groove, and an installation groove extending along its axial direction is provided on the end face of the middle shaft, and both ends of the limiting protrusion are respectively fitted in the limiting groove and the installation groove.

7. The compression mechanism of the rotary compressor according to any one of claims 1-6, It is characterized in that a C-shaped retaining ring is provided on the end face of at least one of the first eccentric part and the second eccentric part facing away from the middle shaft, and the C-shaped retaining ring is sleeved between the first rotating shaft and the first eccentric part or between the second rotating shaft and the second eccentric part.

8. The compression mechanism of the rotary compressor according to any one of claims 1-6, It is characterized in that the first end plate is provided with a first bearing for cooperating with the first rotating shaft and the second end plate is provided with a second bearing for cooperating with the second rotating shaft.

9. The compression mechanism of the rotary compressor according to any one of claims 1-6, It is characterized in that an intermediate bearing is provided between the middle shaft and the partition plate, and a shaft end bearing is provided at one end of the second rotating shaft away from the second end plate.

10. The compression mechanism of the rotary compressor according to any one of claims 1-6, It is characterized in that the first rotating shaft, the second rotating shaft and the middle shaft are all steel parts, and at least one of the first eccentric part and the second eccentric part is a powder alloy part.

11. A rotary compressor, It is characterized in that comprising: a housing, the housing is provided with a discharge port; the compression mechanism of the rotary compressor according to any one of claims 1-10, the compression mechanism is arranged in the housing; a driving mechanism, the driving mechanism is arranged in the housing and is in transmission connection with the crankshaft.

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