Rotary compressor and air conditioning device

Abstract

The axial length A of the first space (S1), the axial length B of the second space (S2), the inner diameter D of the shell (20), the suction volume Vcc of the compression mechanism (30) per rotation, and the maximum rotation speed Nmax of the compression mechanism (30) satisfy 0.8≤(A+B)*D 2 / (Vcc*Nmax)≤1.0.

Description

Technical Field

[0001] The present disclosure relates to a rotary compressor and an air conditioning device. Background Art

[0002] Generally speaking, in a rotary compressor, an electric motor and a compression mechanism are housed in a cylindrical casing whose ends are closed, and the compression mechanism is driven by the electric motor (see, for example, Patent Document 1).

[0003] The compressor of Patent Document 1 uses a concentrated winding motor to reduce the size of the coil, thereby ensuring a space in the housing for separating the lubricating oil and the refrigerant. In this compressor, the relationship between the height L1 of the space in the housing above the motor and the height L2 of the motor (the height from the upper end to the lower end of the coil) is set to 0.3≤L1 / (L1+L2)≤0.6, thereby suppressing the enlargement of the housing.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent No. 3670890 Summary of the invention

[0007] -Technical problem to be solved by the invention-

[0008] However, in Patent Document 1, when the compressor rotates at high speed, the flow rate of the refrigerant in the shell increases, so the lubricating oil is sprayed outside the shell without being fully separated from the refrigerant. As a result, the outflow of oil increases, which may reduce the reliability of the compressor.

[0009] An object of the present disclosure is to enable lubricating oil and refrigerant to be sufficiently separated in a casing even when a compressor rotates at a high speed.

[0010] -Technical solutions to solve technical problems-

[0011] The first aspect of the present disclosure relates to a rotary compressor, which includes a housing 20, a motor 40 and a compression mechanism 30. The housing 20 is cylindrical and has a first end plate 22 at one axial end and a second end plate 23 at the other axial end. The motor 40 is variable speed and is arranged in the housing 20 with a first space S1 between it and the first end plate 22. The compression mechanism 30 is arranged in the housing 20 with a second space S2 between it and the motor 40 and is connected to the motor 40. When the axial length of the first space S1 is A (mm), the axial length of the second space S2 is B (mm), the inner diameter of the housing 20 is D (mm), and the suction volume of the compression mechanism 30 per rotation is Vcc (mm).3 ), assuming that the maximum speed of the compression mechanism 30 is Nmax (rps), 0.8≤(A+B)*D 2 / (Vcc*Nmax)≤1.0.

[0012] In the first aspect, the ratio of the volume of the space in the housing 20 to the suction volume of the compressor at the maximum speed, that is, (A+B)*D 2 By setting the value of / (Vcc*Nmax) within the above range, even when the compressor is operated at a high rotation speed, the lubricating oil and the refrigerant can be sufficiently separated in the casing (20).

[0013] A second aspect of the present disclosure is a rotary compressor according to the first aspect, wherein the relationship of D<100 and Nmax≥118 is satisfied.

[0014] In the second aspect, particularly when the housing is miniaturized and the compressor is accelerated, the lubricating oil and the refrigerant can be sufficiently separated in the housing.

[0015] A third aspect of the present disclosure is a rotary compressor according to the first or second aspect, wherein 0.85≤(A+B)*D is satisfied. 2 / (Vcc*Nmax)≤0.95.

[0016] In the third aspect, by defining the range of the volume ratio to be narrower than that of the first aspect, when the compressor is rotated at a high speed, the refrigerant and the lubricating oil can be more fully separated in the casing.

[0017] A fourth aspect of the present disclosure is a rotary compressor according to any one of the first to third aspects, wherein the rotary compressor satisfies 6×10 3 ≤Vcc≤8×10 3 relationship.

[0018] A fifth aspect of the present disclosure relates to an air conditioning device, which includes a refrigerant circuit 1 that performs a vapor compression refrigeration cycle, wherein the compressor 10 in the refrigerant circuit 1 is the rotary compressor described in any one of the first to fourth aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a cross-sectional view of a rotary compressor according to an embodiment;

[0020] Figure 2A It is shown that (A+B)*D 2 A table showing the relationship between the volume ratio (the ratio of the space volume in the casing to the suction volume of the compressor at the maximum speed) expressed by Vcc*Nmax and the oil leakage rate;

[0021] Figure 2B It is shown that (A+B)*D 2 A curve diagram showing the relationship between the volume ratio and the oil running rate represented by / (Vcc*Nmax);

[0022] Figure 3A It is shown that (A+B)*D 2 A table showing the relationship between the volume ratio represented by / (Vcc*Nmax) and the vibration value of the compressor;

[0023] Figure 3B It is shown that (A+B)*D 2 Graph showing the relationship between the volume ratio represented by Vcc / (Vcc*Nmax) and the vibration value of the compressor. DETAILED DESCRIPTION

[0024] Hereinafter, embodiments will be described in detail with reference to the drawings.

[0025] The rotary compressor (hereinafter referred to as compressor) 10 involved in this embodiment is a swing piston compressor 10. Figure 1 As shown, it is connected to the refrigerant circuit 1. In the refrigerant circuit 1, the compressor 10, the radiator 2, the expansion mechanism 3 and the evaporator 4 are sequentially connected by the refrigerant pipe 5, and the refrigerant circulates in the refrigerant circuit 1 to perform a vapor compression refrigeration cycle. The expansion mechanism 3 generally uses an expansion valve with an adjustable opening, but it can also be other components such as a capillary tube with a fixed opening.

[0026] The compressor 10 includes a shell 20. The shell 20 is a longitudinally elongated cylindrical closed container having a first end plate 22 at one axial end (upper end) of a cylindrical body 21 and a second end plate 23 at the other end (lower end). Inside the shell 20, a compression mechanism 30 for compressing the refrigerant in the refrigerant circuit 1 and a variable speed motor 40 for driving the compression mechanism 30 are accommodated, and the compression mechanism 30 and the motor 40 are respectively fixed to the inner circumferential surface of the body 21. The motor 40 is provided in the shell 20 with a first space S1 between it and the first end plate 22, and a second space S2 between the compression mechanism 30 and the motor 40.

[0027] The motor 40 includes a stator 41 and a rotor 42, both of which are formed in a cylindrical shape. The stator 41 is fixed to the body 21 of the housing 20. The rotor 42 is arranged in the hollow part of the stator 41. The drive shaft 45 is fixed to the hollow part of the rotor 42 in a manner of penetrating the rotor 42, and the rotor 42 and the drive shaft 45 rotate integrally.

[0028] The drive shaft 45 has a main shaft portion 46 extending in the up-down direction. An eccentric portion 47 is integrally formed on the drive shaft 45 near the lower end of the main shaft portion 46. The eccentric portion 47 is formed to have a larger diameter than the main shaft portion 46. The axis of the eccentric portion 47 is offset from the axis of the main shaft portion 46 by a predetermined distance.

[0029] An oil supply pump 48 is provided at the lower end of the main shaft portion 46. The oil supply pump 48 is immersed in the lubricating oil in the oil reservoir formed at the bottom of the housing 20. The oil supply pump 48 draws the lubricating oil into the oil supply passage (not shown) in the drive shaft 45 as the drive shaft 45 rotates, and then supplies the lubricating oil to each sliding part of the compression mechanism 30.

[0030] The compression mechanism 30 has a cylinder 31 formed in an annular shape. A front cylinder head 32 is fixed to one axial end (upper end) of the cylinder 31, and a rear cylinder head 33 is fixed to the other axial end (lower end) of the cylinder 31. The cylinder 31, the front cylinder head 32, and the rear cylinder head 33 are stacked in the order of the front cylinder head 32, the cylinder 31, and the rear cylinder head 33 from the upper side to the lower side, and are fixed to each other by, for example, fastening with a plurality of bolts.

[0031] The drive shaft 45 vertically penetrates the compression mechanism 30. The front cylinder head 32 and the rear cylinder head 33 are provided with bearings 32a and 33a for supporting the drive shaft 45 at upper and lower sides of the eccentric portion 47.

[0032] The upper end of the cylinder 31 is sealed by the front cylinder head 32, while the lower end of the cylinder 31 is sealed by the rear cylinder head 33. The internal space of the cylinder 31 constitutes a cylinder chamber 35. A cylindrical piston 34 that is slidably engaged with the eccentric portion 47 of the drive shaft 45 is accommodated in the cylinder 31 (cylinder chamber 35). When the drive shaft 45 rotates, the piston 34 performs eccentric rotational motion in the cylinder chamber 35. A blade extending radially outward from the outer peripheral surface is integrally formed on the outer peripheral surface of the piston 34, which is not shown in detail in the figure. The blade is held by a bushing (not shown) provided on the piston 34, and swings as the drive shaft 45 rotates, and the rotation of the piston 34 is restricted.

[0033] The cylinder 31 is formed with a suction port 31a communicating with the cylinder chamber 35. The suction port 31a is connected to a suction pipe 36 fixed to the trunk 21. The suction pipe 36 is connected to a liquid reservoir 37 fixed to the housing 20.

[0034] The front cylinder head 32 is provided with a discharge port 32b in a direction parallel to the axis of the drive shaft 45. The discharge port 32b is opened and closed by a discharge valve (not shown). A muffler 38 is mounted on the upper surface of the front cylinder head 32 so as to cover the discharge port 32b and the discharge valve. The muffler 38 is formed such that a muffler space 38a defined therein communicates with the internal space of the housing 20 through a discharge opening 38b at the upper portion.

[0035] As described above, the housing ( 20 ) is provided with the suction pipe ( 36 ) connected to the suction port ( 31 a ), and the refrigerant is sucked into the compression mechanism ( 30 ) through the accumulator ( 37 ) and the suction pipe ( 36 ).

[0036] The discharge pipe 39 penetrates the first end plate 22 and is mounted on the shell 20. The lower end of the discharge pipe 39 opens to the inside of the shell 20. The discharge port 32b of the compression mechanism 30 is connected to the internal space of the shell 20 through the discharge opening 38b of the muffler 38. The refrigerant discharged from the compression mechanism 30 flows out of the shell 20 through the internal space of the shell 20 and the discharge pipe 39.

[0037] A terminal 50 is provided on the first end plate 22 of the housing 20 , and the terminal 50 is connected with an electrical wiring for supplying power to the motor 40 .

[0038] In the compressor of this embodiment, if the axial length of the first space S1 is A (mm), the axial length of the second space S2 is B (mm), the inner diameter of the shell 20 is D (mm), and the suction volume per rotation of the compression mechanism 30 is Vcc (mm), then 3 ), assuming that the maximum speed of the compression mechanism 30 is Nmax (rps), then 0.8≤(A+B)*D 2 / (Vcc*Nmax)≤1.0.

[0039] In this embodiment, D<100, Nmax≥118, 6×10 3 ≤Vcc≤8×10 3 The values ​​of A and B can be appropriately determined (for example, A can be approximately 50 to 70 mm, and B can be approximately 20 to 30 mm).

[0040] Under this condition, Figure 2A Table and Figure 2B The graph shows the use of (A+B)*D 2 The relationship between the volume ratio (the ratio of the space volume in the housing to the suction volume of the compressor 10 at the highest speed) represented by / (Vcc*Nmax) and the oil escape rate at multiple points in the range from about 0.70 to 1.20. Figure 3A Table and Figure 3BThe graph of shows the relationship between the volume ratio and the vibration amount (the vibration amount of the housing 20 ) at a plurality of points where the value of the volume ratio is within a range of approximately 0.70 to 1.10 under the same conditions.

[0041] The oil escape rate is the ratio of the total amount of oil to the amount of oil flowing out of the housing 20. The smaller the volume ratio, in other words, the smaller the space volume in the housing 20 relative to the suction volume at the maximum speed, the greater the oil escape rate, and the greater the amount of oil flowing out of the housing 20. The larger the volume ratio, in other words, the larger the space volume in the housing 20 relative to the suction volume Vcc at the maximum speed Nmax, the smaller the oil escape rate, and the smaller the amount of oil flowing out of the housing 20.

[0042] In this embodiment, the volume ratio satisfies 0.8≤(A+B)*D 2 / (Vcc*Nmax)≤1.0, such as Figure 2A , Figure 2B As shown, the oil escape rate is in the range of 0.91 to 0.35. When the volume ratio is less than 0.8, the oil escape rate increases. In contrast, in this embodiment, the increase in the oil escape rate can be suppressed. If the volume ratio is greater than 1.0, the oil escape rate remains approximately constant, so there is no need to excessively increase the space volume in the housing 20, and the enlargement of the housing 20 can be suppressed.

[0043] The volume ratio satisfies 0.8≤(A+B)*D 2 / (Vcc*Nmax)≤1.0, such as Figure 3A , Figure 3B As shown, the vibration amount (μm) of the housing 20 is in the range of 27.5 to 30 (μm). When the volume ratio is less than 0.8, the vibration amount becomes smaller, but the oil leakage rate becomes larger. In contrast, in this embodiment, both the vibration amount and the oil leakage rate are suppressed. Although the vibration amount becomes larger when the volume ratio is greater than 1.0, the oil leakage rate can be suppressed and the vibration amount can be reduced in this embodiment.

[0044] - Effects of implementation -

[0045] In the existing compressor, if the diameter of the body is reduced to achieve miniaturization, and the rotation speed is increased to ensure the discharge volume, the average gas flow velocity from the compression mechanism toward the discharge pipe increases, the oil separation effect in the space inside the shell becomes worse, and the oil leakage increases. On the other hand, if the space volume inside the shell is increased, the compressor will become larger.

[0046] In this embodiment, the volume ratio is set to 0.8≤(A+B)*D 2 / (Vcc*Nmax)≤1.0. In this way, in the present embodiment, not only the oil leakage rate is suppressed by increasing the spatial volume in the housing 20, but also the range of the volume ratio is determined so that the vibration amount is reduced. In particular, miniaturization can be achieved by suppressing the height of the housing 20 of the compressor 10 from becoming larger, and by suppressing the height of the housing 20, vibration can be suppressed even if the compressor 10 is operated at a high speed, and at the same time, an increase in the oil leakage rate can be suppressed.

[0047] In this embodiment, since the vibration of the compressor 10 can be suppressed, damage to the housing 20 and the pipe due to the vibration can be suppressed. Since the oil escape rate can be suppressed, the reliability of the sliding part of the compressor 10 can be suppressed from being reduced.

[0048] In the present embodiment, the relationship D<100 and Nmax≥118 is satisfied. In the present embodiment, in the compressor 10 in which the casing 20 is reduced in diameter and the operation speed is increased, vibration of the casing 20 can be suppressed and an increase in the oil leakage rate can be suppressed.

[0049] In this embodiment, 6×10 3 ≤Vcc≤8×10 3 In the present embodiment, in such a small capacity compressor, the vibration of the casing 20 can be suppressed, and at the same time, an increase in the oil leakage rate can be suppressed.

[0050] In the air conditioning apparatus including the compressor of this embodiment, by suppressing the oil leakage rate of the compressor 10, it is possible to suppress the lubricating oil from adhering to the heat exchangers 2 and 4 in the refrigerant circuit to hinder heat transfer, thereby suppressing a decrease in system efficiency.

[0051] (Other embodiments)

[0052] The above-described embodiment may also adopt the following structure.

[0053] <Variation 1>

[0054] In the above embodiment, the volume ratio can also be set to 0.85≤(A+B)*D 2 / (Vcc*Nmax)≤0.95.

[0055] In this way, by limiting the range of the volume ratio to a narrower range than that of the above embodiment, the oil escape rate can be further reduced compared with the above embodiment, and the size increase of the housing 20 can be further suppressed, and the vibration amount can also be reduced. As a result, the effect of suppressing damage to the housing 20 and the pipe, reduction in reliability of the compressor 10, and reduction in system efficiency can be improved.

[0056] <Variation 2>

[0057] In the above embodiment, the volume ratio may be within a range of 0.9≤(A+B)*D^2 / (Vcc*Nmax)≤1.0.

[0058] In this way, the oil escape rate can be further reduced compared with the above-mentioned embodiment and modification 1, and the size of the housing 20 can be easily suppressed and the vibration amount can be reduced as in the embodiment and modification 1. As a result, damage to the housing 20 and the pipe can be suppressed, and the reliability and system efficiency of the compressor 10 can be further suppressed.

[0059] The above embodiments and variations are described, but it should be understood that various changes can be made to the methods and specific matters without departing from the spirit and scope of the claims. It is also possible to appropriately combine or replace the elements involved in the above embodiments, variations, and other embodiments.

[0060] - Industrial Applicability -

[0061] In summary, the present disclosure is useful for a rotary compressor and an air conditioning device.

[0062] - Explanation of symbols -

[0063] 1 Refrigerant circuit

[0064] 10Rotary compressor

[0065] 20 Shell

[0066] 22 First end plate

[0067] 23 Second end plate

[0068] 30Compression mechanism

[0069] 40 Electric Motor

[0070] S1 First Space

[0071] S2 Second Space

Claims

1. A rotary compressor, characterized in that: The rotary compressor comprises: A cylindrical housing (20) having a first end plate (22) at one axial end and a second end plate (23) at the other axial end; a variable speed motor (40) disposed in the housing (20) with a first space (S1) between the motor and the first end plate (22); and A compression mechanism (30) is provided in the housing (20) with a second space (S2) between the motor (40) and the compression mechanism (30), and is connected to the motor (40). When the axial length of the first space (S1) is A and the unit is mm, the axial length of the second space (S2) is B and the unit is mm, the inner diameter of the shell (20) is D and the unit is mm, and the suction volume of the compression mechanism (30) per rotation is Vcc and the unit is mm 3 , assuming that the maximum rotation speed of the compression mechanism (30) is Nmax and the unit is rps, 0.8≤(A+B)*D 2 / (Vcc*Nmax)≤1.

0.

2. The rotary compressor according to claim 1, characterized in that: D<100,Nmax≥118.

3. The rotary compressor according to claim 1 or 2, characterized in that: 0.85≤(A+B)*D 2 / (Vcc*Nmax)≤0.95。 4. The rotary compressor according to any one of claims 1 to 3, characterized in that: 6×10 3 ≤Vcc≤8×10 3 。 5. An air conditioning device, characterized in that: The air conditioning device comprises a refrigerant circuit (1) which performs a vapor compression refrigeration cycle. The compressor (10) in the refrigerant circuit (1) is a rotary compressor according to any one of claims 1 to 4.

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