WO2007123074A1

WO2007123074A1 - Compressor

Info

Publication number: WO2007123074A1
Application number: PCT/JP2007/058246
Authority: WO
Inventors: Masahide Higuchi; Yasukazu Nabetani; Azusa Ujihara; Hideki Mori
Original assignee: Daikin Industries, Ltd.
Priority date: 2006-04-19
Filing date: 2007-04-16
Publication date: 2007-11-01
Also published as: KR101156261B1; EP2009285B1; CN101415948A; US20090100861A1; AU2007242125B2; EP2009285A4; JP5050393B2; EP2009285A1; ES2594654T3; KR20080099347A; JP2007285266A; AU2007242125A1

Abstract

The stator core (510) of a motor (3) has a plurality of oil return passages (530) extending through one surface (510a) and the other surface (510b) of the core. On the other surface (510b) of the stator core (510), the hydraulic diameter of each oil return passage (530) is 5 mm or larger, and the ratio of the total area of the oil return passages (530) to the area of the virtual circle having the diameter equal to the maximum outer diameter of the stator core (510) is 5 to 15%. Thereby, the lubricating oil accumulated on the other surface (510b) side of the stator core (510) can be returned to an oil reservoir (9) through the oil return passages (530), and it can be prevented that the oil reservoir (9) is short of oil. Furthermore, the cross sectional area of the stator core (510) can be securely kept, and the motor efficiency can be maintained.

Description

Specification

Compressor

Technical field

[0001] The present invention relates to a compressor used in, for example, an air conditioner or a refrigerator.

Background art

Conventionally, a compressor includes a hermetic container, a compression element disposed in the hermetic container, and a motor disposed in the hermetic container and driving the compression element via a shaft. An oil reservoir portion in which lubricating oil was accumulated was formed at the bottom of the closed container (see Japanese Patent Publication No. 2003-262192).

Disclosure of the invention

Problems to be solved by the invention

[0003] However, in the conventional compressor, since the passage force S passing through the upper and lower portions of the motor is small, the lubricating oil collected in the upper portion of the motor is located on the lower side of the motor. There was a problem that the oil level of the oil sump portion was cut off. Due to the oil level cut, the oil in the oil reservoir cannot be effectively sent to the sliding elements such as the compression element and the motor bearing via the shaft, and the reliability of the compressor is reduced. The sex was decreasing. In particular, when diacid carbon is used as the refrigerant, a lubricating oil having a high viscosity is used as the lubricating oil, and therefore, the lubricating oil is more difficult to return to the oil reservoir.

Accordingly, an object of the present invention is to provide a compressor that prevents oil level cut of the oil reservoir while maintaining motor efficiency.

Means for solving the problem

[0005] In order to solve the above problems, a compressor according to the present invention provides:

A sealed container having an oil reservoir;

A compression element disposed in the sealed container;

A motor disposed in the sealed container and driving the compression element via a shaft; The stator core of the motor has a plurality of oil return passages penetrating one surface of the stator core on the oil reservoir portion side and the other surface of the stator core on the opposite side of the oil reservoir portion,

In the other surface of the stator core,

The hydraulic diameter of each of the oil return passages is 5 mm or more, and the ratio of the total area of the plurality of oil return passages to the area of a virtual circle whose diameter is the maximum outer diameter of the stator core is 5% to 15 It is characterized by%.

[0006] According to the compressor of the present invention, in the other surface of the stator core, the hydraulic diameter of each of the oil return passages is 5 mm or more, and a virtual circle whose diameter is the maximum outer diameter of the stator core. Since the ratio of the total area of the plurality of oil return passages to the area is 5% to 15%, the lubricating oil accumulated on the other surface side of the stator core is passed through the plurality of oil return passages to the stator core. It is possible to return to the oil sump portion on the one surface side, and it is possible to prevent the oil sump portion from being cut off. At the same time, the cross-sectional area of the stator core can be ensured, and motor efficiency can be maintained. In particular, when diacid carbon is used as the refrigerant, a lubricating oil having a high viscosity is used, but the lubricating oil can be effectively returned to the oil reservoir.

[0007] Further, in the compressor according to an embodiment, the stator core is disposed on a radially outer side of the rotor of the motor, and the oil return passage is on an outer peripheral side of the stator core.

According to the compressor of this embodiment, since the oil return passage is on the outer peripheral side of the stator core, it adheres to the lubricating oil blown radially outward by the rotor or the inner surface of the sealed container. Lubricating oil can be effectively guided to the oil return passage, and the oil level of the oil reservoir can be more reliably prevented.

[0009] In the compressor according to the embodiment, the refrigerant in the sealed container is carbon dioxide.

According to the compressor of this embodiment, since the refrigerant in the sealed container is carbon dioxide, high-viscosity lubricating oil is used. However, the oil reservoir is effectively lubricated. Oil can be returned.

The invention's effect

[0011] According to the compressor of the present invention, each of the oil return portions is provided on the other surface of the stator core. The hydraulic diameter of the passage is 5 mm or more, and the ratio of the total area of the plurality of oil return passages to the area of a virtual circle whose diameter is the maximum outer diameter of the stator core is 5% to 15%. While the motor efficiency is maintained, it is possible to prevent the oil reservoir from being cut off. Brief Description of Drawings

FIG. 1 is a longitudinal sectional view showing an embodiment of a compressor of the present invention.

FIG. 2 is a plan view of the main part of the compressor.

FIG. 3 is a cross-sectional view of the vicinity of the compressor motor.

FIG. 4 is an enlarged view of part A in FIG.

FIG. 5 is a graph showing the relationship between oil level breakage and motor efficiency, hydraulic diameter and area ratio.

FIG. 6A is a graph showing the relationship between the area ratio and the motor efficiency reduction rate.

FIG. 6B is a graph showing the relationship between the area ratio and the oil level height reduction rate.

FIG. 7A is a graph showing the relationship between hydraulic diameter and motor efficiency reduction rate.

FIG. 7B is a graph showing the relationship between hydraulic diameter and oil level height reduction rate.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.

FIG. 1 is a longitudinal sectional view showing an embodiment of a compressor according to the present invention. The compressor includes a hermetic container 1, a compression element 2 disposed in the hermetic container 1, and a motor 3 disposed in the hermetic container 1 and driving the compression element 2 via a shaft 12. ing.

[0015] This compressor is a so-called vertical high-pressure dome-type rotary compressor, in which the compression element 2 is placed down and the motor 3 is placed up in the sealed container 1. The rotor 6 of the motor 3 drives the compression element 2 via the shaft 12.

The compression element 2 sucks refrigerant gas from the accumulator 10 through the suction pipe 11. This refrigerant gas is obtained by controlling a condenser, an expansion mechanism, and an evaporator (not shown) constituting an air conditioner as an example of a refrigeration system together with the compressor.

[0017] The refrigerant gas is carbon dioxide and has a high pressure of about 12 MPa in the sealed container 1. A refrigerant such as R410A or R22 may be used as the refrigerant. [0018] The compressor discharges the compressed high-temperature and high-pressure refrigerant gas from the compression element 2 so as to fill the inside of the sealed container 1, and the gap between the stator 5 of the motor 3 and the rotor 6 is filled. The motor 3 is cooled through the gap, and then discharged from the discharge pipe 13 provided on the upper side of the motor 3 to the outside.

[0019] An oil reservoir 9 in which lubricating oil is stored is formed at a lower portion of the high-pressure region in the closed container 1. This lubricating oil moves from the oil reservoir 9 through the oil passage (not shown!) Provided in the shaft 12 to a sliding part such as a bearing of the compression element 2 or the motor 3. To lubricate the sliding part.

[0020] When diacid carbon is used as the refrigerant, a lubricating oil having a high viscosity is used as the lubricating oil. As this lubricating oil, a lubricating oil of 5 to 300 cSt at a viscosity of 0 ° C is used. This lubricating oil is, for example, a polyalkylene glycol oil (such as polyethylene glycol or polypropylene glycol), an ether oil, an ester oil, or a mineral oil.

[0021] The compression element 2 includes a cylinder 21 attached to the inner surface of the hermetic container 1, an upper end plate member 50 and a lower end plate attached to the upper and lower open ends of the cylinder 21, respectively. Member 60. A cylinder chamber 22 is formed by the cylinder 21, the upper end plate member 50 and the lower end plate member 60.

The upper end plate member 50 includes a disk-shaped main body 51 and a boss 52 provided upward in the center of the main body 51. The main body 51 and the boss 52 are inserted through the shaft 12. The main body 51 is provided with a discharge port 5 la communicating with the cylinder chamber 22.

[0023] A discharge valve 31 is attached to the main body 51 so that the main body 51 is positioned on the opposite side of the cylinder 21. The discharge valve 31 is, for example, a reed valve, and opens and closes the discharge port 51a.

A cup-type muffler cover 40 is attached to the main body 51 so as to cover the discharge valve 31 on the side opposite to the cylinder 21. The muffler cover 40 is fixed to the main body 51 by a fixing member 35 (such as a bolt). The muffler cover 40 is passed through the boss portion 52 described above.

A muffler chamber 42 is formed by the muffler cover 40 and the upper end plate member 50. To do. The muffler chamber 42 and the cylinder chamber 22 are communicated with each other through the discharge port 51a.

The muffler cover 40 has a hole 43. The hole 43 communicates the muffler chamber 42 with the outside of the muffler cover 40.

[0027] The lower end plate member 60 includes a disk-shaped main body 61 and a boss 62 provided downward in the center of the main body 61. The main body 61 and the boss 62 are inserted into the shaft 12!

In short, one end of the shaft 12 is supported by the upper end plate member 50 and the lower end plate member 60. That is, the shaft 12 is cantilevered. One end (support end side) of the shaft 12 enters the inside of the cylinder chamber 22.

An eccentric pin 26 is provided on the support end side of the shaft 12 so as to be positioned in the cylinder chamber 22 on the compression element 2 side. The eccentric pin 26 is fitted to the roller 27. The roller 27 is disposed in the cylinder chamber 22 so as to be capable of revolving, and is configured so as to perform a compression action by the revolving motion of the roller 27.

In other words, one end of the shaft 12 is supported by the housing 7 of the compression element 2 on both sides of the eccentric pin 26. The housing 7 includes the upper end plate member 50 and the lower end plate member 60.

[0031] Next, the compression action of the cylinder chamber 22 will be described.

As shown in FIG. 2, the cylinder chamber 22 is partitioned by a blade 28 provided integrally with the roller 27. That is, in the chamber on the right side of the blade 28, the suction pipe 11 opens on the inner surface of the cylinder chamber 22 to form a suction chamber (low pressure chamber) 22a. On the other hand, in the chamber on the left side of the blade 28, the discharge port 51a (shown in FIG. 1) opens on the inner surface of the cylinder chamber 22 to form a discharge chamber (high pressure chamber) 22b.

[0033] Semi-cylindrical bushes 25, 25 are in intimate contact with both surfaces of the blade 28 for sealing. The blade 28 and the bushes 25, 25 are lubricated with the lubricating oil.

[0034] Then, the eccentric pin 26 rotates eccentrically with the shaft 12, and the roller 27 fitted to the eccentric pin 26 is connected to the outer peripheral surface of the roller 27 by the inner peripheral surface of the cylinder chamber 22. Revolves in contact with.

As the roller 27 revolves in the cylinder chamber 22, the blade 28 advances and retreats with both side surfaces of the blade 28 being held by the bushes 25, 25. Then, a low-pressure refrigerant gas is sucked into the suction chamber 22a from the suction pipe 11 and compressed to a high pressure in the discharge chamber 22b, and then the high-pressure refrigerant gas is discharged from the discharge port 5la (shown in FIG. 1). Exhaust refrigerant gas.

Thereafter, as shown in FIG. 1, the refrigerant gas discharged from the discharge port 51 a is discharged to the outside of the muffler cover 40 via the muffler chamber 42.

As shown in FIGS. 1 and 3, the motor 3 includes the rotor 6 and the stator 5 disposed on the radially outer side of the rotor 6 via an air gap.

[0038] The rotor 6 includes a rotor main body 610 and a magnet 620 embedded in the rotor main body 610. The rotor body 610 has a cylindrical shape, and is made of laminated electromagnetic steel plates, for example. The shaft 12 is attached to the central hole of the rotor body 610. The magnet 620 is a flat permanent magnet. The six magnets 620 are arranged in the circumferential direction of the rotor main body 610 at equally spaced center angles.

The stator 5 includes a stator core 510 and a coil 520 wound around the stator core 510. In FIG. 3, a part of the coil 520 is omitted.

[0040] The stator core 510 has an annular portion 511, and nine teeth 512 that protrude from the inner peripheral surface of the annular portion 511 radially inward and are arranged at equal intervals in the circumferential direction. The stator core 510 also has a plurality of laminated steel plate forces. The coil 520 is a so-called concentrated winding which is wound around each of the teeth 512 and is not wound around the plurality of teeth 512.

[0041] The motor 3 is a so-called 6-pole 9-slot. The rotor 6 is rotated together with the shaft 12 by an electromagnetic force generated in the stator 5 by passing a current through the coil 520.

[0042] The stator core 510 passes through one surface (lower surface) 510a of the stator core 510 on the oil reservoir 9 side and the other surface (upper surface) 5 10b of the stator core 510 on the opposite side of the oil reservoir 9. A plurality of oil return passages 530. The oil return passage 530 is on the outer peripheral side of the stator core 510. The oil return passage 530 is formed by a so-called core cut such as a concave groove or a D cut surface formed on the outer peripheral surface of the stator core 510. That is, the oil return passage 530 is a space surrounded by the inner surface of the core cut and the inner peripheral surface lb of the sealed container 1.

[0044] The oil return passage 530 is disposed on the radially outer side of each of the teeth 512, and there are nine as the number of the teeth 512. The oil return passage 530 is formed in a substantially rectangular shape when viewed from the direction of the central axis la of the sealed container 1.

[0045] On the other surface 510b of the stator core 510, the hydraulic diameter of each of the oil return passages 530 is 5 mm or more, and the plurality of the above-mentioned plurality of areas with respect to the area of a virtual circle whose diameter is the maximum outer diameter of the stator core 510 The ratio of the total area of the oil return passage 530 (hereinafter referred to as area ratio) is 5% to 15%.

[0046] The hydraulic diameter of the oil return passage 530 is, as shown in FIG. 4, the area of the oil return passage 530 on the other surface 510b as S, and the oil return on the other surface 510b. When the circumference of the passage 530 is L, it is expressed as 4SZL. FIG. 4 is an enlarged view of part A in FIG.

[0047] The area S of the oil return passage 530 is an area surrounded by the inner surface of the concave groove of the stator core 510 and the inner peripheral surface lb of the hermetic container 1 as indicated by oblique lines in FIG. . The circumferential length L of the oil return passage 530 is calculated by combining the length of the inner surface of the upper groove of the stator core 510 and the length of the inner circumferential surface lb of the sealed container 1 as shown by the thick line in FIG. It is the obtained value.

The virtual circle whose diameter is the maximum outer diameter of the stator core 510 coincides with the inner peripheral surface lb of the hermetic container 1 as shown in FIG. In other words, the area of this imaginary circle coincides with the cross-sectional area inside the sealed container 1 on the other surface 510b. The total area of the plurality of oil return passages 530 refers to the total number of areas S of the oil return passages 530 on the other surface 510b.

[0049] According to the compressor configured as described above, on the other surface 510b of the stator core 510, the hydraulic diameter of each oil return passage 530 is 5 mm or more, and the area ratio is 5% to 15%. Therefore, the lubricating oil that flows to the downstream side (upper side) of the motor 3 together with the refrigerant gas and accumulates on the other surface 510b side of the stator core 510 passes through the plurality of oil return passages 530 to the stator core. The oil can be returned to the oil reservoir 9 on the one surface 510a side of 510, and the oil level of the oil reservoir 9 can be prevented from running out. And this oil level cut prevention Thus, the lubricating oil in the oil reservoir 9 can be effectively sent to the sliding part such as the bearing of the compression element 2 and the motor 3 through the shaft 12, and the reliability of the compressor can be improved. improves.

[0050] At the same time, the sectional area of the stator core 510 can be secured, and the motor efficiency can be maintained.

In particular, when diacid carbon is used as the refrigerant, a lubricating oil having a high viscosity is used, but the lubricating oil can be effectively returned to the oil reservoir 9.

[0051] Here, only on the other surface 510b of the stator core 510, when the hydraulic diameter of each oil return passage 530 satisfies 5 mm, the lubricating oil overcomes the viscosity by its own weight, and the oil return passage 530 And move to the oil reservoir 9.

[0052] On the other hand, when the hydraulic diameter of each oil return passage 530 is smaller than 5 mm, the planar shape of the oil return passage 530 becomes, for example, a slit shape, and the lubricating oil is mixed with the stator core due to viscosity. The oil adheres to the other surface 510b of 510, does not move down the oil return passage 530, and does not move to the oil reservoir 9 described above. That is, there is a problem of running out of oil. On the other hand, when the hydraulic diameter of each oil return passage 530 is larger than 15 mm, the effective surface area of the annular portion 511 of the stator core 510 becomes small, resulting in a problem that the motor efficiency is lowered.

[0053] If the area ratio is smaller than 5%, the quantity of the oil return passage 530 decreases, and the lubricating oil cannot be effectively returned to the oil reservoir 9 and the oil level is cut. There's a problem. On the other hand, when the area ratio is larger than 15%, the quantity and area of the oil return passage 530 are increased, and the surface area of the stator core 510 is decreased, resulting in a problem that the motor efficiency is lowered.

[0054] In the present invention, the hydraulic diameter of each of the oil return passages 530 is preferably 20 mm or less (more preferably 15 mm or less), and the cross-sectional area of the stator core 510 can be more reliably ensured. Efficiency can be maintained more reliably.

Further, since the oil return passage 530 is on the outer peripheral side of the stator core 510, the oil return passage 530 is formed on the lubricating oil blown radially outward by the port 6 or the inner peripheral surface lb of the sealed container 1. The adhering lubricating oil can be effectively guided to the oil return passage 530, and the oil level of the oil reservoir 9 can be more reliably prevented.

[0056] Next, FIG. 5 shows the relationship between the oil level breakage and motor efficiency, and the hydraulic diameter and area ratio. The The horizontal axis shows the hydraulic diameter of each oil return passage, and the vertical axis shows the area ratio (ratio of the total area of the oil return passage to the stator core outer diameter area).

[0057] First region Zl, that is, hydraulic diameter is 5mn! ~ 15mm and area ratio is 5% ~ 15

When it is%, there is no problem in both the oil level cut and the motor efficiency.

[0058] When the second region Z2, that is, the hydraulic diameter is larger than 15 mm and the area ratio is 5% to 15%, there is no problem with the oil level breakage with a slight problem in motor efficiency.

[0059] When the third region Z3, that is, the hydraulic diameter is 5 mm or more and the area ratio is larger than 15%, there is no problem in oil level cut, but there is a problem in motor efficiency.

[0060] In at least one of the fourth region Z4, that is, when the hydraulic diameter is smaller than 5 mm and when the area ratio is smaller than 5%, there is no problem in motor efficiency, but there is a problem in oil level breakage. The

Next, the grounds of the graph of FIG. 5 are shown in FIGS. 6A, 6B, 7A, and 7B.

FIG. 6A shows the relationship between the area ratio (ratio of the total area of the oil return passage to the stator core outer diameter area) and the motor efficiency reduction rate. The vertical axis shows the motor efficiency decrease rate, and the lower the vertical axis, the lower the motor efficiency. As shown in FIG. 6A, when the area ratio is larger than 15%, the motor efficiency is extremely lowered.

FIG. 6B shows the relationship between the area ratio (ratio of the total area of the oil return passage to the stator core outer diameter area) and the oil level height reduction rate. The vertical axis shows the oil level drop rate, and the lower the vertical axis, the lower the oil level. As can be seen from FIG. 6B, when the area ratio is less than 5%, the oil level is extremely lowered.

[0064] In other words, if the total area of the oil return passage is large, the motor efficiency decreases, so the area ratio (ratio of the total area of the oil return passage Z outer diameter area of the stator core) needs to be smaller than 15%. . Also, if the total area of the oil return passage is small, the oil return performance will deteriorate and the oil level cannot be secured. Therefore, the area ratio (ratio of total area of oil return passage Z stator core outer diameter area) should be greater than 5%.

FIG. 7A shows the relationship between the hydraulic diameter of each oil return passage and the motor efficiency reduction rate. The vertical axis shows the motor efficiency decrease rate, and the lower the vertical axis, the lower the motor efficiency. As shown in Fig. 7A, if the hydraulic diameter is larger than 15mm, there will be a problem with motor efficiency. come.

FIG. 7B shows the relationship between the hydraulic diameter of each oil return passage and the oil level height reduction rate. The vertical axis shows the oil level drop rate, and the lower the vertical axis, the lower the oil level. As shown in Fig. 7B, if the hydraulic diameter is smaller than 5mm, the oil level is extremely lowered.

[0067] In other words, if the hydraulic diameter is large, the surface area of the annular portion 511 of the stator core 510 is reduced, and the motor efficiency is reduced. Therefore, the hydraulic diameter should be less than 15mm. In addition, when the hydraulic diameter is small, the oil return property is deteriorated, so that the oil level cannot be secured. Therefore, the hydraulic diameter needs to be larger than 5mm.

Note that the present invention is not limited to the above-described embodiment. For example, the compression element 2 may be a rotary type in which a roller and a blade are separate bodies. As the compression element 2, in addition to the rotary type, a scroll type or a reciprocating type may be used. The compression element 2 may be a two-cylinder type having two cylinder chambers. The coil 520 may be distributed over the plurality of teeth 512 as well as any distributed winding! /.

[0069] Further, the compression element 2 may be disposed on the upper side and the motor 3 may be disposed on the lower side. The oil return passage 530 may be provided on the inner peripheral side of the stator core 510, or may be provided in a central portion between the inner peripheral surface and the outer peripheral surface of the stator core 510. Further, the oil return passages 530 may be provided at any positions in the circumferential direction of the stator core 510, and may be provided at equal pitches or unequal pitches.

Claims

The scope of the claims

[1] a sealed container (1) having an oil sump (9);

A compression element (2) arranged in this sealed container (1);

A motor (3) disposed in the sealed container (1) and driving the compression element (2) via a shaft (12);

With

The stator core (510) of the motor (3) includes one surface (510a) of the stator core (510) on the oil reservoir (9) side and the stator core (51 on the opposite side of the oil reservoir (9)). 0) having a plurality of oil return passages (530) penetrating the other surface (510b),

In the other surface (510b) of the stator core (510),

The hydraulic diameter of each of the oil return passages (530) is 5 mm or more, and the plurality of oil return passages (530) with respect to the area of a virtual circle whose diameter is the maximum outer diameter of the stator core (510). A compressor characterized in that the ratio of the total area is 5% to 15%.

[2] In the compressor according to claim 1,

The stator core (510) is disposed radially outside the rotor (6) of the motor (3), and the oil return passage (530) is on the outer peripheral side of the stator core (510). Machine.

[3] In the compressor according to claim 1,

The compressor characterized in that the refrigerant in the sealed container (1) is carbon dioxide.