Rotary Compressor

Abstract

To provide a rotary compressor capable of avoiding excessive supply of lubrication oil to be supplied to a rotary compression mechanism part and securing strength even when a diameter of a shaft is reduced.SOLUTION: A rotary compressor includes: a closed vessel; an electric part disposed on one side in the closed vessel; a rotary compression mechanism part disposed on the other side in the closed vessel; a shaft connecting the electric part with the rotary compression mechanism part; and lubrication oil stored in the closed vessel. The rotary compression mechanism part includes: an eccentric part; a roller fitted to the eccentric part; a cylinder accommodating the roller; and a bearing plate closing the cylinder and supporting the shaft. The bearing plate includes an oil supply passage having one end facing the lubrication oil and the other end communicated with inside of the cylinder.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a rotary compressor. [Background technology]

[0002] For example, rotary compressors have been provided as compressors for air conditioners. The rotary compressor includes an electric motor, a rotary compression mechanism connected to a shaft (crankshaft) corresponding to the rotation axis of the electric motor and driven by the operation of the electric motor, and a sealed container that houses the electric motor and the rotary compression mechanism. Such rotary compressors are disclosed, for example, in Patent Documents 1 and 2 listed below. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-182429 [Patent Document 2] Special Publication No. 2020-526707 Summary of the Invention [Problem to be solved by the invention]

[0004] In general rotary compressors such as those disclosed in Patent Documents 1 and 2, for example, lubricating oil for lubricating appropriate locations within the rotary compression mechanism (sliding areas between the rotating roller and the cylinder, shaft, main bearing (main frame), sub-bearing (bearing plate), etc.) is stored in a sealed container. Also, as shown in Patent Document 1, an oil supply passage for supplying lubricating oil is provided in the core of the shaft, and a member called a paddle, which is made of a twisted metal plate, is attached to the inside of the oil supply passage. As a result, the lubricating oil is sucked into the oil supply passage by the pressure difference between the inside and outside of the cylinder (compression chamber) and the centrifugal force of the paddle, and is supplied to the appropriate locations within the rotary compression mechanism.

[0005] However, if the lubricating oil supply mechanism includes a paddle, the amount of oil supplied to the rotary compression mechanism may be excessively large depending on the operating conditions, for example, during high-speed operation. Furthermore, in recent years, shafts have been made smaller in diameter to reduce the weight of rotary compressors and energy loss in the sliding area. However, the conventional structure with an oil supply passage inside the shaft may not be able to ensure the shaft strength. Therefore, a design to compensate for the shaft strength is required.

[0006] The present invention has been made in view of the above-mentioned problems, and aims to provide a rotary compressor that can avoid excessive supply of lubricating oil to a rotary compression mechanism and that ensures strength even when the shaft diameter is reduced. [Means for solving the problem]

[0007] The rotary compressor according to the present invention comprises: A sealed container and an electric motor disposed on one side of the sealed container; a rotary compression mechanism disposed on the other side of the sealed container; a shaft connecting the electric motor and the rotary compression mechanism; Lubricating oil stored in the sealed container; Equipped with The rotary compression mechanism includes: a roller that rotates eccentrically in accordance with the rotation of the shaft; a cylinder that houses the roller; a bearing plate that closes the cylinder and supports the shaft; Equipped with The bearing plate has one end facing the lubricating oil and the other end facing the inner diameter side of the roller. position and an oil supply passage that is opened and closed by the roller. It is characterized by:

[0008] According to this aspect of the present invention, an oil supply passage is provided in the bearing plate, one end of which faces the lubricating oil and the other end of which is connected to the inside of the cylinder of the rotary compression mechanism, and the lubricating oil can be supplied to the rotary compression mechanism (e.g., inside the cylinder) by the pressure difference between the inside and outside of the cylinder. Therefore, excessive supply of lubricating oil to the rotary compression mechanism can be avoided.

[0009] Furthermore, according to this aspect of the present invention, since the lubricating oil is supplied to the rotary compression mechanism through the oil supply passage provided in the bearing plate, it is not necessary to provide a separate oil supply passage in the shaft, and therefore the strength of the shaft is sufficiently ensured even if the diameter of the shaft is reduced.

[0010] Further, in the rotary compressor according to the present invention, The oil supply passage is opened and closed depending on the rotation angle of the shaft. It is preferable.

[0011] According to this aspect of the present invention, by locating the oil supply passage in a sliding area between the eccentric rotating element (such as a roller or a thrust bearing) attached to the eccentric portion and the bearing plate (for example, an area where the lower end surface of the roller overlaps with the upper end surface of the bearing plate during the roller's operation), it is possible to switch between opening and closing the oil supply passage according to the rotation angle of the shaft. In other words, with such a simple structure, it is possible to control the amount of oil supplied to the rotary compression mechanism.

[0012] Furthermore, in the rotary compressor according to the present invention, The bearing plate is provided with a plurality of the oil supply passages, At least one of the plurality of oil supply passages and another of the plurality of oil supply passages are opened at different times depending on the rotation angle of the shaft. It is preferable.

[0013] According to this aspect of the present invention, by providing a plurality of oil supply passages in the sliding region between the eccentric rotating element and the bearing plate, at least one oil supply passage opens at a different timing from the other oil supply passages depending on the rotation angle of the shaft, thereby enabling continuous supply of lubricating oil to the rotary compression mechanism.

[0014] Furthermore, in the rotary compressor according to the present invention, The shaft may include an internal shaft oil supply structure including an oil supply passage extending longitudinally within the shaft. [Effects of the Invention]

[0015] According to the present invention, it is possible to provide a rotary compressor that can avoid excessive lubricating oil being supplied to a rotary compression mechanism and that can ensure strength even when the shaft diameter is reduced. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a vertical cross-sectional view of a rotary compressor according to an embodiment of the present invention. [Figure 2] 2 is a partial cross-sectional view of a rotary compression mechanism in the present embodiment (a partial cross-sectional view taken along line AA in FIG. 1). [Figure 3] 4 is a timing chart showing the transition of the fuel supply amount in this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0017] A rotary compressor according to an embodiment of the present invention will be described in detail below with reference to the drawings. First, the overall configuration of a rotary compressor 1 according to an embodiment of the present invention will be described with reference to Fig. 1. Here, Fig. 1 is a vertical cross-sectional view of the rotary compressor 1.

[0018] 1, a rotary compressor 1 according to this embodiment includes an electric motor 10 and a rotary compression mechanism 20 driven by the electric motor 10. The electric motor 10 and the rotary compression mechanism 20 are housed in a sealed container 30 made of steel plate and including a container body 31 and a lid 32.

[0019] The motor unit 10 is disposed on one side (upper side in the height direction) within the sealed container 30, and the rotary compression mechanism unit 20 is disposed on the other side (lower side in the height direction) within the sealed container 30.

[0020] The electric motor 10 is a brushless DC motor including a stator 11, a rotor 12, and a shaft 13 (a crankshaft corresponding to the rotation axis of the rotor 12). Here, the stator 11 includes a laminate (stator core) 11a formed by stacking a plurality of electromagnetic steel plates in the height direction, each having a doughnut shape in plan view with a substantially cylindrical air space formed inside, and a stator coil 11b wound by a concentrated winding method around teeth provided on the laminate 11a.

[0021] The stator coil 11b is electrically connected to a terminal 33 attached to the lid 32 of the container 30. When power is supplied to the stator coil 11b from the terminal 33, a current flows through the stator coil 11b. This generates a rotating magnetic field that acts on the rotor 12, causing the rotor 12 to rotate.

[0022] The rotor 12 includes a laminate (rotor core) 12a formed by stacking a plurality of electromagnetic steel plates, each of which has a generally circular shape in plan view, in the height direction, and permanent magnets provided within the laminate 12a. The laminate 12a of the rotor 12 is disposed in a cylindrical cavity formed inside the stator 11. At this time, a small gap is formed between the inner ends of the teeth of the stator 11 and the outer surface of the rotor 12. Furthermore, a through-hole 12b is formed in the center of the rotor 12, penetrating it in the height direction. A shaft 13 is inserted into the through-hole 12b to support the rotor 12.

[0023] Next, as shown in Fig. 1, the rotary compression mechanism 20 includes a cylinder 21, an eccentric portion 22, a roller 23, a thrust receiving portion 24, etc. Here, as shown in Fig. 1, the cylinder 21 includes an internal compression chamber 211 that penetrates vertically. Also, a main frame 25 and a bearing plate 26 that support the shaft 13 are attached to the upper and lower surfaces of the cylinder 21, respectively. The opening of the cylinder 21 (compression chamber 211) is closed by the main frame 25 and the bearing plate 26.

[0024] As shown in FIG. 1, the eccentric portion 22 is housed within the compression chamber 211 and is integrally formed with the shaft 13. The rollers 23 are provided around the outer surface of the eccentric portion 22. The vanes (not shown) are slidably disposed within vertical grooves (vane slots) formed in the cylinder 21 and face the compression chamber 211. At this time, the inner ends of the vanes abut against the outer surfaces of the rollers 23. This divides the compression chamber 211 into a low-pressure chamber and a high-pressure chamber. A coil spring (not shown) is disposed on the outer side of the vertical groove and biases the outer ends of the vanes.

[0025] In the rotary compression mechanism 20 having the above structure, when the shaft 13 rotates, the eccentric portion 22 and the roller 23 rotate eccentrically within the compression chamber 211. At this time, the roller 23 rotates eccentrically along the inner surface of the compression chamber 211. In addition, as the roller 23 rotates eccentrically, the vane that contacts the outer surface of the roller 23 is pushed outward from the cylinder 21. As the roller 23 continues to rotate eccentrically, the vane slides in the opposite direction and returns to its original position.

[0026] Although the illustrated rotary compression mechanism 20 includes one cylinder 21, the number of cylinders is not limited to this. That is, the rotary compression mechanism 20 may include two or more cylinders 21.

[0027] Furthermore, an oil reservoir formed at the bottom (the other end) of the sealed container 30 stores lubricating oil 40 for lubricating the rotary compression mechanism 20 (the sliding area between the cylinder 21 and the roller 23, the sliding area between the roller 23 and the main frame 25, and the sliding area between the roller 23 and the bearing plate 26, etc.).

[0028] 1, bearing plate 26, which closes the opening on the other side (the lower side in the height direction in this embodiment) of cylinder 21 (compression chamber 211), abuts against cylinder 21 and includes flange portion 261 that protrudes in the width direction, and bearing portion 262 that extends downward from flange portion 261 and supports shaft 13. Furthermore, through passages 263 (263a, 263b) are formed in bearing portion 262 and are provided along the height direction.

[0029] Furthermore, one end of the through passage 263 faces the lubricating oil 40, and the other end of the through passage 263 communicates with the inside of the cylinder 21 (the inner diameter side of the roller 23). Here, the pressure in the low-pressure section in the cylinder 21 (compression chamber 211) is lower than the lubricating oil pressure (cylinder external pressure). At this time, the pressure on the inner diameter side of the roller 23 also drops through a clearance formed, for example, at the top in the height direction of the roller 23, which connects the cylinder 21 (compression chamber 211) and the inner diameter side of the roller 23. As a result, the lubricating oil 40 drawn up to the inner diameter side of the roller 23 through the through passage 263 is sucked up into the inside of the cylinder 21 (the inner diameter side of the roller 23) and the sliding part. In other words, the through passage 263 functions as a passage for supplying the lubricating oil into the cylinder 21. For this reason, the through passage will be referred to as an "oil supply passage" hereinafter.

[0030] According to this embodiment, since the oil supply passage 263 is provided in the bearing plate 26, there is no need to provide an oil supply passage in the shaft 13 as in the conventional oil supply mechanism. Therefore, even if the diameter of the shaft 13 is reduced, sufficient strength is ensured. Furthermore, since the lubricating oil 40 is sucked up using the differential pressure between the inside and outside of the cylinder 21, it is possible to prevent excessive supply of the lubricating oil 40 to the rotary compression mechanism 20 (cylinder 21).

[0031] In this embodiment, the oil supply passage 263 is provided in the bearing portion 262 of the bearing plate 26, but it may be provided in another location on the bearing plate 26, such as the flange portion 261. Also, while two oil supply passages 263a and 263b are shown in Figure 1, the number of oil supply passages 263 is not limited to this. As described above, the number of oil supply passages 263 is basically multiple, but a single (one) oil supply passage may be used for optimization.

[0032] Next, the operation of the rotary compressor 1 of this embodiment will be described with reference to Figures 2 and 3. Here, Figure 2 is a partial cross-sectional view of the rotary compression mechanism 20 (a partial cross-sectional view cut along line AA in Figure 1), and is a diagram illustrating the positional relationship between the eccentric rotation elements (roller 23, thrust receiving portion 24, etc.) in the rotary compression mechanism 20 and the oil supply passage 263 according to the rotation angle (crank angle) of the shaft 13. Also, Figure 3 is a timing chart showing the transition of the oil supply amount in this embodiment.

[0033] 2, when the rotation angle of shaft 13 is 0°, one of oil supply passages 263 (oil supply passage 263a) overlaps the lower end of roller 23. This causes oil supply passage 263a to be closed. In contrast, the other of oil supply passages 263 (oil supply passage 263b) does not overlap with roller 23 and is open.

[0034] Next, when roller 23 rotates until the rotation angle of shaft 13 reaches 90°, both oil supply passages 263a and 263b overlap the lower end of roller 23 and are closed. When roller 23 further rotates until the rotation angle of shaft 13 reaches 135°, oil supply passage 263a, which had been closed until then, opens. When roller 23 further rotates until the rotation angle of shaft 13 reaches 270°, both oil supply passages 263a and 263b of shaft 13 again overlap the lower end of roller 23 and are closed. When roller 23 further rotates until the rotation angle of shaft 13 reaches 360° (0°), oil supply passage 263a is closed, while oil supply passage 263b is open.

[0035] The transition of the amount of oil supplied based on the opening and closing operation of oil supply passages 263a and 263b is as shown in Figure 3. That is, when the rotation angle of shaft 13 is from 0° to 90° (period A in Figure 3), lubricating oil 40 is supplied from oil supply passage 263b to cylinder 21 (the inner diameter side of roller 23) (the amount of oil supplied from oil supply passage 263b is shown by a dashed line). At this time, lubricating oil 40 is not supplied from oil supply passage 263a (the amount of oil supplied from oil supply passage 263b is shown by a broken line).

[0036] In contrast, when the rotation angle of shaft 13 changes from 90° to 270° (period B in FIG. 3), lubricating oil 40 is supplied from oil supply passage 263a to cylinder 21 (the inner diameter side of roller 23), but lubricating oil 40 is not supplied from oil supply passage 263b. Finally, when the rotation angle of shaft 13 changes from 90° to 270° (period C in FIG. 3), lubricating oil 40 is again supplied from oil supply passage 263b to cylinder 21 (the inner diameter side of roller 23), but lubricating oil 40 is not supplied from oil supply passage 263a.

[0037] In this way, by arranging oil supply passage 263 facing the sliding area between the eccentric rotation element (roller 23 in this embodiment) of rotary compression mechanism 20 and bearing plate 26, oil supply passage 263a and oil supply passage 263b open and close at different times depending on the rotation angle of the eccentric rotation element. As a result, as shown in FIG. 3, the period during which oil supply passage 263a is open and the period during which oil supply passage 263b is open are alternately switched. As a result, lubricating oil 40 can be continuously supplied into rotary compression mechanism 20 (cylinder 21).

[0038] In this embodiment, the oil supply passages 263a and 263b are provided in the sliding area between the roller 23 and the bearing plate 26, but the positions of the oil supply passages 263a and 263b are not limited thereto. For example, even if the oil supply passages 263a and 263b are located in the sliding area between the thrust receiving portion 24 and the bearing plate 26, the same effect is achieved.

[0039] Furthermore, within the scope of ensuring the rigidity of shaft 13, an oil supply structure (a central hole (oil supply passage) extending in the longitudinal direction of shaft 13, or in some cases a structure to which a paddle is added; this is referred to as an "intra-shaft oil supply structure") may be provided within shaft 13. This intra-shaft oil supply structure may be combined with oil supply passage 263 to further optimize the amount of oil supplied.

[0040] Furthermore, although the case where two oil supply passages 263 are provided has been described, when there is one oil supply passage 263, the open period and closed period (oil supply period and non-oil supply period) of the oil supply passage 263 are switched according to the rotation angle of the shaft 13. This makes it possible to control the amount of oil supplied to the rotary compression mechanism 20 with a simple structure in which the oil supply passage 263 is provided in the sliding area between the eccentric rotation element (roller 23, thrust receiving portion 24, etc.) and the bearing plate 26.

[0041] The embodiments of the present invention have been described in detail. However, the above description is provided to facilitate understanding of the present invention and is not intended to limit the present invention. The present invention may include modifications and improvements to the above-described embodiments without departing from the spirit of the present invention. The present invention also includes equivalents thereof. [Industrial Applicability]

[0042] The rotary compressor according to the present invention is used in, for example, home and commercial air conditioners, etc. However, its use is not limited to this. [Explanation of symbols]

[0043] 1. Rotary compressor 10········Electric part 11. Stator 12 Rotor 13. Rotor shaft 20 Rotary compression mechanism 21 Cylinder 211... Compression chamber 22 Eccentric part 23. Laura 24 Thrust receiving part 25 Mainframe 26 Bearing plate 263 Fuel line 30. Airtight container 40...Lubricating oil

Claims

1. A sealed container and an electric motor disposed on one side of the sealed container; a rotary compression mechanism disposed on the other side of the sealed container; a shaft connecting the electric motor and the rotary compression mechanism; Lubricating oil stored in the sealed container; Equipped with The rotary compression mechanism includes: a roller that rotates eccentrically in accordance with the rotation of the shaft; a cylinder that houses the roller; a bearing plate that closes the cylinder and supports the shaft; Equipped with The bearing plate has one end facing the lubricating oil and the other end located on the inner diameter side of the roller, and has an oil supply passage that is opened and closed by the roller. A rotary compressor characterized by:

2. The oil supply passage is opened and closed depending on the rotation angle of the shaft. The rotary compressor according to claim 1 .

3. The bearing plate is provided with a plurality of the oil supply passages, At least one of the plurality of oil supply passages and another of the plurality of oil supply passages are opened at different times depending on a rotation angle of the shaft. The rotary compressor according to claim 1 or 2.

4. The shaft is provided with an in-shaft oil supply structure including an oil supply passage extending longitudinally inside the shaft. The rotary compressor according to any one of claims 1 to 3.

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