WO2016139735A1

WO2016139735A1 - Rotary compressor

Info

Publication number: WO2016139735A1
Application number: PCT/JP2015/056121
Authority: WO
Inventors: 祐策石部
Original assignee: 三菱電機株式会社
Priority date: 2015-03-02
Filing date: 2015-03-02
Publication date: 2016-09-09
Also published as: JP6429987B2; JPWO2016139735A1; CN205503462U

Abstract

This rotary compressor 100 is provided with the following: a compression mechanism section 50 that compresses a refrigerant; a crankshaft 5 that transmits a rotational driving force to the compression mechanism section 50; a primary bearing 9 and an auxiliary bearing 12, which are slide bearings having inner diameter surfaces that slidably support the crankshaft 5; and a rolling bearing 19 having an outer ring section 19b fixed to a groove 9a provided on the inner diameter surface of the slide bearing, and an inner ring section 19a rotatably supported by the slide bearing. A clearance 20 is present between the outer diameter surface of the crankshaft 5 and the inner ring section 19a of the roll bearing 19.

Description

Rotary compressor

The present invention relates to a rotary compressor.

As a conventional rotary compressor, for example, a structure in which a rolling bearing structure is provided on an upper part of a sliding bearing has been proposed (for example, see Patent Document 1). In addition, as a conventional rotary compressor, one in which a rolling bearing is provided on an inner diameter portion of a sliding bearing has been proposed (for example, see Patent Documents 2 to 4).

JP 2008-169827 A JP 2001-323886 A JP 2007-285180 A JP-A-5-256283

However, the slide bearing as described in Patent Document 1 has a problem that the contact portion between the crankshaft and the slide bearing may be damaged when the refrigeration oil is exhausted. In addition, the rolling bearings described in Patent Documents 1 to 4 have a problem that a certain sliding loss occurs due to friction in the rolling bearing.

The present invention has been made to solve the above-described problem, and provides a rotary compressor capable of preventing damage to a contact portion between a crankshaft and a bearing and reducing sliding loss. Objective.

The rotary compressor of the present invention includes a compression mechanism portion that compresses refrigerant, a crankshaft that transmits a rotational driving force to the compression mechanism portion, and a plain bearing that has an inner diameter surface that slidably supports the crankshaft, A rolling bearing having an outer ring portion fixed to a groove provided on an inner diameter surface of the slide bearing and an inner ring portion rotatably supported by the slide bearing, the outer diameter surface of the crankshaft and the rolling bearing; A clearance is provided between the inner ring portion and the inner ring portion.

The rotary compressor of the present invention has a clearance between the outer diameter surface of the crankshaft and the inner ring portion of the rolling bearing, and when the refrigerating machine oil is exhausted, the outer diameter surface of the crankshaft is the inner ring portion of the rolling bearing. When it comes into contact with the inner ring, it slides integrally with the inner ring portion of the rolling bearing. When an oil seal is formed in the clearance, the inner ring portion of the rolling bearing functions as a sliding bearing for the crankshaft. Therefore, according to this invention, while preventing the damage of the contact part of a crankshaft and a slide bearing, the rotary compressor which can reduce a sliding loss can be provided.

It is sectional drawing which shows roughly an example of the rotary compressor 100 which concerns on Embodiment 1 of this invention. It is an expanded sectional view showing roughly compression mechanism part 50 of rotary compressor 100 concerning Embodiment 1 of the present invention. It is a top view which shows roughly the structure of the crankshaft 5 of the rotary compressor 100 which concerns on Embodiment 1 of this invention. It is sectional drawing which shows schematically the structure of the main bearing 9 and the rolling bearing 19 of the rotary compressor 100 which concerns on Embodiment 1 of this invention. It is a top view which shows roughly the structure of the rolling bearing 19 of the rotary compressor 100 which concerns on Embodiment 1 of this invention. It is a graph which shows roughly the effect of rotary compressor 100 concerning Embodiment 1 of the present invention.

Embodiment 1 FIG.
The configuration of the rotary compressor 100 according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view schematically showing an example of a rotary compressor 100 according to Embodiment 1 of the present invention. FIG. 2 is an enlarged cross-sectional view schematically showing the compression mechanism unit 50 of the rotary compressor 100 according to Embodiment 1 of the present invention. FIG. 3 is a plan view schematically showing the structure of the crankshaft 5 of the rotary compressor 100 according to Embodiment 1 of the present invention. In the following drawings including FIGS. 1 to 3, the dimensional relationship and shape of each component may be different from the actual ones. Moreover, in the following drawings, the same code | symbol is attached | subjected to the same or similar member or part, or attaching | subjecting code | symbol is abbreviate | omitted.

FIG. 1 illustrates a vertical two-cylinder rotary compressor 100 as an example. The rotary compressor 100 includes a sealed container 1 that is a cylinder-shaped housing. A motor 30 is accommodated in the upper part of the sealed container 1, and a compression mechanism part 50 is accommodated in the lower part. The inside of the sealed container 1 is filled with a high-pressure gas refrigerant compressed by the compression mechanism unit 50, and the refrigerating machine oil 2 for lubricating the compression mechanism unit 50 is sealed at the bottom of the sealed container 1. .

The motor 30 includes a rotor 3 and a stator 4, and the stator 4 is fixed to the inner surface of the hermetic container 1. The motor 30 rotates the rotor 3 by energizing the stator 4. For example, a DC brushless motor or the like is used.

The crankshaft 5 passes through the center of the rotor 3 and is fixed to the rotor 3. The crankshaft 5 includes a cylindrical first eccentric portion 5a and a cylindrical second eccentric portion 5b disposed below the first eccentric portion 5a. The second eccentric portion 5b is disposed so as to face the first eccentric portion 5a 180 degrees with respect to the central axis of the crankshaft 5.

As shown in FIGS. 1 and 2, the compression mechanism portion 50 includes a first cylinder 6 having a cylindrical hollow portion in which a first eccentric portion 5 a of the crankshaft 5 can rotate, and a second cylinder shaft 5. The eccentric part 5b is provided with the 2nd cylinder 7 which has a cylindrical hollow part which can rotate. The outer surfaces of the first cylinder 6 and the second cylinder 7 are fixed to the inner surface of the sealed container 1.

The compression mechanism 50 includes an intermediate plate 8 that is fixed between the first cylinder 6 and the second cylinder 7 and separates the hollow portion of the first cylinder 6 and the hollow portion of the second cylinder 7. . The intermediate plate 8 has an inner diameter surface that slidably supports a rotating portion located between the first eccentric portion 5a and the second eccentric portion 5b of the crankshaft 5.

The compression mechanism unit 50 includes a main bearing 9 and a sub-bearing 12 which are sliding bearings. The main bearing 9 is fixed to the upper surface of the first cylinder 6 and has an inner diameter surface that supports the crankshaft 5 in a slidable manner. The auxiliary bearing 12 is fixed to the lower surface of the second cylinder 7 and has an inner diameter surface that supports the crankshaft 5 in a slidable manner.

A hollow portion of the first cylinder 6 surrounded by the intermediate plate 8 and the main bearing 9 constitutes a first compression chamber 10. In the first compression chamber 10, a first rolling piston 11 that is rotatably attached to the outer periphery of the first eccentric portion 5a of the crankshaft 5 is disposed. The hollow portion of the second cylinder 7 surrounded by the intermediate plate 8 and the auxiliary bearing 12 constitutes a second compression chamber 13. In the hollow portion of the second cylinder 7, a second rolling piston 14 that is rotatably attached to the outer periphery of the second eccentric portion 5 b of the crankshaft 5 is disposed.

As shown in FIG. 1, the crankshaft 5 has one end extending to the bottom of the sealed container 1 so that the refrigerating machine oil 2 sealed in the bottom of the sealed container 1 can be supplied to the compression mechanism 50. An oil separator 15 for suppressing the refrigerating machine oil 2 from flowing out of the rotary compressor 100 is fitted to one end of the crankshaft 5 in the upper direction of the sealed container 1. As shown in FIG. 3, a hollow hole 5 c that extends along the axial direction from one end of the crankshaft 5 on the bottom side of the sealed container 1 and sucks up the refrigerating machine oil 2 is formed in the axial center portion of the crankshaft 5. Is provided.

Further, as shown in FIG. 3, the crankshaft 5 is provided with a first oil supply hole 5d, a second oil supply hole 5e, a third oil supply hole 5f, and a fourth oil supply hole 5g. .

The first oil supply hole 5d is located above the first eccentric portion 5a of the crankshaft 5, branches from the hollow hole 5c, and extends to the outer diameter surface of the crankshaft 5. The first oil supply hole 5 d is provided to supply the refrigerating machine oil 2 between the inner diameter surface of the main bearing 9 and the outer diameter surface of the crankshaft 5.

The second oil supply hole 5e is located inside the first eccentric portion 5a of the crankshaft 5, branches from the hollow hole 5c, and extends to the outer diameter surface of the first eccentric portion 5a. The second oil supply hole 5 e is provided for supplying the refrigerating machine oil 2 to the inside of the first compression chamber 10.

The third oil supply hole 5f is located inside the second eccentric portion 5b of the crankshaft 5, branches from the hollow hole 5c, and extends to the outer diameter surface of the second eccentric portion 5b. The third oil supply hole 5 f is provided for supplying the refrigerating machine oil 2 to the inside of the second compression chamber 13.

The fourth oil supply hole 5g is located below the second eccentric portion 5b of the crankshaft 5, branches from the hollow hole 5c, and extends to the outer diameter surface of the crankshaft 5. The fourth oil supply hole 5g is provided to supply the refrigerating machine oil 2 between the inner diameter surface of the auxiliary bearing 12 and the outer diameter surface of the crankshaft 5.

As shown in FIG. 1, the rotary compressor 100 includes a first refrigerant pipe 16 and a second refrigerant pipe 17. The first refrigerant pipe 16 passes through the side surface of the sealed container 1 and communicates with the first compression chamber 10. The first refrigerant pipe 16 allows low-pressure gas refrigerant from a suction muffler (not shown) to flow into the first compression chamber 10 in the first cylinder 6. The second refrigerant pipe 17 passes through the side surface of the sealed container 1 and communicates with the second compression chamber 13. The second refrigerant pipe 17 allows low-pressure gas refrigerant from a suction muffler (not shown) to flow into the second compression chamber 13 in the second cylinder 7.

Further, the rotary compressor 100 includes a discharge pipe 18 that discharges a high-pressure gas refrigerant filled in the sealed container 1 of the rotary compressor 100 to a refrigerant pipe (not shown) of the refrigeration cycle circuit. The discharge pipe 18 passes through the upper surface of the sealed container 1 and communicates with the inside of the sealed container 1.

The main bearing 9 and the sub-bearing 12 which are the sliding bearings of the first embodiment are provided with one or more rolling bearings 19 as shown in FIG. Hereinafter, the structure of the rolling bearing 19 will be described in detail with reference to FIGS.

FIG. 4 is a cross-sectional view schematically showing structures of the main bearing 9 and the rolling bearing 19 of the rotary compressor 100 according to the first embodiment. FIG. 5 is a plan view schematically showing the structure of the rolling bearing 19 of the rotary compressor 100 according to Embodiment 1 of the present invention.

As shown in FIG. 5, the rolling bearing 19 includes a plurality of inner ring portions 19a (inner diameter portions) and outer ring portions 19b (outer diameter portions) which are starting wheels, and a plurality of rollers disposed between the inner ring portion 19a and the outer ring portion 19b. It is a machine element having a hollow cylindrical appearance including a rolling element 19c. The rolling bearing 19 may be a ball bearing or a roller bearing such as a cylindrical roller bearing.

In the rolling bearing 19 according to the first embodiment, the outer surface of the outer ring portion 19b is fixed to a groove 9a provided on the inner diameter surface of the main bearing 9, and the inner ring portion 19a is rotatably supported by the groove 9a. That is, the rolling bearing 19 according to the first embodiment is configured to be fixed to the groove 9 a provided on the inner diameter surface of the main bearing 9. In FIG. 4, a stepped groove 9 a is provided at the upper end and lower end of the inner diameter surface of the main bearing 9, and the outer surface of the outer ring portion 19 b is fixed to the stepped groove 9 a, whereby the rolling bearing 19 is The main bearing 9 is fixed to a groove 9a provided on the inner diameter surface.

In addition, the arrangement position of the rolling bearing 19 according to the first embodiment is not limited to the upper end portion and the lower end portion of the inner diameter surface of the main bearing 9. The rolling bearing 19 according to the first embodiment can be fixed by providing a groove 9a at an arbitrary position of the inner diameter portion of the main bearing 9 and the auxiliary bearing 12 where the refrigerating machine oil 2 is easily depleted.

The crankshaft 5 is slidably supported with respect to the inner ring portion 19a in the hollow portion of the inner ring portion 19a of the rolling bearing 19 according to the first embodiment. In the first embodiment, a clearance 20 is provided between the crankshaft 5 and the inner ring portion 19a of the rolling bearing 19, and the radial width of the clearance 20 is adjusted to be 10 to 50 μm. The That is, in the first embodiment, the outer diameter portion of the crankshaft 5 is configured not to be fitted or fixed to the inner ring portion 19a of the rolling bearing 19.

When the refrigerating machine oil 2 is abundant between the crankshaft 5 and the inner ring portion 19a of the rolling bearing 19, the clearance 20 becomes an oil seal 70 (oil film) as shown by the hatched portion in FIG. The outer diameter portion of the shaft 5 does not come into contact with the inner ring portion 19 a of the rolling bearing 19.

On the other hand, when the refrigerating machine oil 2 between the crankshaft 5 and the inner ring portion 19a of the rolling bearing 19 is exhausted, the clearance 20 becomes a cavity 90 as shown in the black-painted portion in FIG. The outer diameter portion of the shaft 5 can come into contact with the inner ring portion 19 a of the rolling bearing 19.

The load of the refrigerant gas at which the rolling bearing 19 starts to function is set lower than the load at which the inner ring portion 19a, which is the proof stress limit of the inner ring portion 19a of the rolling bearing 19, starts to be damaged.

Next, the operation of the rotary compressor 100 according to the first embodiment will be described.

When a driving voltage is supplied to the stator 4 of the motor 30, the rotor 3 rotates by receiving a rotational force from a rotating magnetic field generated by the stator 4. When the rotor 3 rotates, the crankshaft 5 fixed to the rotor 3 rotates, and the first eccentric portion 5a and the second eccentric portion 5b of the crankshaft 5 rotate eccentrically. In conjunction with the eccentric rotational movement of the first eccentric portion 5a, the first rolling piston 11 rotates eccentrically in the first compression chamber 10, and the volume of the first compression chamber 10 is reduced. In conjunction with the eccentric rotational movement of the second eccentric portion 5b, the second rolling piston 14 rotates eccentrically in the second compression chamber 13, and the volume of the second compression chamber 13 is reduced.

By reducing the volume of the first compression chamber 10, the low-pressure gas refrigerant sucked into the first compression chamber 10 from the first refrigerant pipe 16 is compressed into the high-pressure gas refrigerant, and the sealed container 1 It is discharged inside. By reducing the volume of the second compression chamber 13, the low-pressure gas refrigerant sucked into the second compression chamber 13 from the second refrigerant pipe 17 is compressed into the high-pressure gas refrigerant, and the sealed container 1. It is discharged inside. The high-pressure gas refrigerant discharged into the sealed container 1 is discharged through a discharge pipe 18 to a refrigerant pipe (not shown) of the refrigeration cycle circuit.

In the rotary compressor 100 according to the first embodiment, the second eccentric portion 5b is disposed so as to face the first eccentric portion 5a 180 degrees with respect to the central axis of the crankshaft 5. Therefore, the compression process in the second compression chamber 13 can be shifted by 180 degrees in rotation angle with respect to the compression process in the first compression chamber 10. Therefore, in the two-cylinder rotary compressor 100, the load on the crankshaft 5 can be reduced and the reliability can be improved. Moreover, the fluctuation | variation of the rotational torque of the crankshaft 5 can be made small, and the vibration of a rotation direction can be reduced.

Further, the refrigerating machine oil 2 sealed at the bottom of the sealed container 1 is sucked up by the centrifugal pump principle from the hollow hole 5c provided in the crankshaft 5 by the centrifugal force generated by the rotation of the crankshaft 5. The refrigerating machine oil 2 sucked up into the hollow hole 5c is supplied to the compression mechanism section 50 as lubricating oil (lubricant) through the first oil supply hole 5d to the fourth oil supply hole 5g. For example, the refrigerating machine oil 2 is supplied from the first oil supply hole 5 d between the inner diameter surface of the main bearing 9 and the outer diameter surface of the crankshaft 5. The refrigerating machine oil 2 is supplied into the first compression chamber 10 from the second oil supply hole 5e. The refrigerating machine oil 2 is supplied into the second compression chamber 13 from the third oil supply hole 5f. From the fourth oil supply hole 5g, the refrigerating machine oil 2 is supplied between the inner diameter surface of the auxiliary bearing 12 and the outer diameter surface of the crankshaft 5.

For example, when the refrigerating machine oil 2 is supplied into the first compression chamber 10 through the second oil supply hole 5e, an oil film formed by the refrigerating machine oil 2 is formed in the gap between the intermediate plate 8 and the crankshaft 5. It is formed. By forming the oil film, refrigerant leakage from the first compression chamber 10 or the second compression chamber 13 is avoided, so that the compression performance in the first compression chamber 10 or the second compression chamber 13 can be improved. it can. Further, since the oil film is formed, it is possible to avoid the direct contact between the inner diameter surface of the intermediate plate 8 and the outer diameter surface of the crankshaft 5, so that the compression mechanism section 50 can be prevented from being damaged.

The refrigerating machine oil 2 includes an inner ring portion 19a of a rolling bearing 19 disposed on the inner diameter surface of the main bearing 9 and the sub-bearing 12 which are sliding bearings via the first oil supply hole 5d and the fourth oil supply hole 5g. The clearance 20 between the crankshaft 5 and the outer diameter surface is supplied with oil. By supplying the refrigerating machine oil 2 to the clearance 20, an oil seal 70 is formed in the clearance 20 as shown in FIG. By forming the oil seal 70, the crankshaft 5 rotates without contacting the inner ring portion 19 a of the rolling bearing 19. That is, the rolling bearing 19 functions as a sliding bearing.

Here, consider a case where the rotary compressor 100 is started in a state where the refrigerating machine oil 2 has accumulated at the bottom of the hermetic container 1 and the refrigerant has been liquefied and dissolved in the refrigerating machine oil 2 because it has not been operated for a long time. When the rotary compressor 100 is started, the refrigerating machine oil 2 in the clearance 20 is depleted, and a cavity 90 is formed in the clearance 20 as shown in FIG. When the cavity 90 is formed in the clearance 20, the outer diameter portion of the crankshaft 5 can come into contact with the inner ring portion 19 a of the rolling bearing 19. When the outer diameter portion of the crankshaft 5 comes into contact with the inner ring portion 19 a of the rolling bearing 19, the inner ring portion 19 a of the rolling bearing 19 slides integrally with the crankshaft 5. That is, in a state where the refrigerating machine oil 2 is depleted, the inner ring portion 19 a of the rolling bearing 19 exhibits its original function as the rolling bearing 19.

Note that a part of the refrigerating machine oil 2 supplied into the first compression chamber 10 or the second compression chamber 13 is a high-pressure gas refrigerant compressed in the first compression chamber 10 or the second compression chamber 13. Together, they are discharged from the first compression chamber 10 or the second compression chamber 13. The mixed fluid of the high-pressure gas refrigerant flowing toward the discharge pipe 18 and the refrigerating machine oil 2 collides with the oil separator 15 fitted to the upper part of the crankshaft 5, and the refrigerant and the refrigerating machine oil 2 are separated by centrifugal force. The refrigerating machine oil 2 is returned to the bottom of the sealed container 1. That is, in the rotary compressor 100 according to the first embodiment, the refrigeration oil 2 is discharged to the refrigerant pipe (not shown) of the refrigeration cycle circuit through the discharge pipe 18 by the centrifugal separation structure of the oil separator 15. Is suppressed.

As described above, in the rotary compressor 100 according to the first embodiment, the outer ring portion 19b of the rolling bearing 19 is fixed to the groove 9a provided on the inner diameter surfaces of the main bearing 9 and the sub bearing 12 that are sliding bearings. The inner ring portion 19a of the rolling bearing 19 is slidably supported, and a clearance 20 is provided between the outer diameter surface of the crankshaft 5 slidably supported by the inner ring portion 19a and the inner ring portion 19a of the rolling bearing 19. It is what has. The effect of the rotary compressor 100 according to the first embodiment will be described with reference to FIG.

FIG. 6 is a graph schematically showing the effect of the rotary compressor 100 according to Embodiment 1 of the present invention. The horizontal axis of the graph indicates the amount of the refrigerating machine oil 2 in the clearance 20, that is, the thickness of the oil seal 70. The vertical axis of the graph represents sliding loss. A region indicated by a symbol A on the horizontal axis indicates a state where the refrigerating machine oil 2 is depleted, that is, a state where a cavity 90 is formed in the clearance 20. A region indicated by a symbol B on the horizontal axis indicates a state where the refrigerator oil 2 is rich, that is, a state where the oil seal 70 is formed in the clearance 20. The boundary between the code A and the code B is indicated by a one-dot chain line.

6 represents the sliding loss in the rotary compressor 100 according to the first embodiment. The dotted line in the area of symbol A in FIG. 6 shows the sliding loss when the bearing of the conventional compressor functions as a slide bearing in a state where the refrigerating machine oil 2 is depleted. The double line in the region B in FIG. 6 indicates the sliding loss when the bearing of the conventional compressor functions as a rolling bearing in a state where the refrigerator oil 2 is rich.

As shown in the dotted line graph of FIG. 6, when the bearing functions as a sliding bearing in a state where the refrigerating machine oil 2 is depleted, since the rotating shaft and the bearing are in direct contact, the sliding loss decreases as the oil film decreases. growing. Then, when the sliding loss reaches the numerical value indicated by x on the dotted line graph, there is a problem that the contact portion between the shaft and the bearing is damaged.

Further, as shown in the double line graph of FIG. 6, when the bearing functions as a rolling bearing in a state where the refrigeration oil 2 is abundant, the rotating shaft and the bearing always slide in contact with each other. There was a problem that the sliding loss was increased as compared with the case of using it.

In contrast, the rotary compressor 100 according to the first embodiment has a clearance 20 between the outer diameter surface of the crankshaft 5 and the inner ring portion 19 a of the rolling bearing 19.

When the refrigerating machine oil 2 is depleted, a cavity 90 is formed in the clearance 20. When the cavity 90 is formed, the outer diameter portion of the crankshaft 5 can come into contact with the inner ring portion 19 a of the rolling bearing 19. When the outer diameter surface of the crankshaft 5 comes into contact with the inner ring portion 19 a of the rolling bearing 19, it slides integrally with the inner ring portion 19 a of the rolling bearing 19. That is, as shown in the solid line graph of the region A in FIG. 6, when the crankshaft 5 and the inner ring portion 19a of the rolling bearing 19 are in direct contact, the friction coefficient becomes as close to 1 as possible. The part 19a exhibits the original function as the rolling bearing 19.

On the other hand, when the refrigerating machine oil 2 is abundant, an oil seal 70 is formed in the clearance 20. By forming the oil seal 70, the friction coefficient between the outer diameter surface of the crankshaft 5 and the inner ring portion 19a of the rolling bearing 19 is lowered. That is, since the crankshaft 5 rotates without contacting the inner ring portion 19a of the rolling bearing 19, the rolling bearing 19 functions as a sliding bearing as shown by the solid line graph in the region B of FIG. Become.

As described above, in the rotary compressor 100 according to the first embodiment, depending on the state of the oil seal 70 formed in the clearance 20, there are advantages of both the function as a slide bearing and the original function as a rolling bearing. It is possible to make the most of it, and it is possible to reduce both component damage and sliding loss. Therefore, according to the first embodiment, the rotary compressor 100 capable of preventing damage to the contact portion between the crankshaft 5 and the main bearing 9 and the sub-bearing 12 that are sliding bearings and reducing sliding loss. Can be provided.

Further, according to the first embodiment, since the yield strength when the refrigerating machine oil 2 is depleted is greatly improved, the rotary compressor 100 that can be used for a long time can be provided, and the refrigerating machine oil enclosed in the rotary compressor 100 can be provided. The amount of 2 can be reduced. Therefore, according to the first embodiment, the amount of the refrigerating machine oil 2 discharged from the rotary compressor 100 together with the refrigerant can be reduced. By reducing the amount of the refrigerating machine oil 2 discharged from the rotary compressor 100, for example, it is possible to avoid a decrease in the performance of heat exchange by the refrigerating machine oil 2 in the heat exchanger of the refrigeration cycle.

Further, according to the first embodiment, since the amount of the refrigerating machine oil 2 sealed in the rotary compressor 100 can be reduced, for example, a structure for separating the refrigerating machine oil 2 from the refrigerant such as the oil separator 15 is eliminated. Is also possible. Therefore, it can be said that the configuration of the first embodiment is also effective in reducing the size of the rotary compressor 100 and reducing the material cost.

Other embodiments.
The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, in the first embodiment, the rotary compressor 100 is a vertical type, but may be a horizontal type.

In the first embodiment, the two-cylinder rotary compressor 100 is used, but the present invention is not limited to this. For example, a single-cylinder rotary compressor 100 may be used, or a rotary compressor 100 having three or more cylinders may be used.

1 closed container, 2 refrigerator oil, 3 rotor, 4 stator, 5 crankshaft, 5a first eccentric part, 5b second eccentric part, 5c hollow hole, 5d first oiling hole, 5e second oiling Hole, 5f third oiling hole, 5g fourth oiling hole, 6 first cylinder, 7 second cylinder, 8 intermediate plate, 9 main bearing, 9a groove, 10 first compression chamber, 11 first Rolling piston, 12 sub bearing, 13 second compression chamber, 14 second rolling piston, 15 oil separator, 16 first refrigerant pipe, 17 second refrigerant pipe, 18 discharge pipe, 19 rolling bearing, 19a inner ring Part, 19b outer ring part, 19c rolling element, 20 clearance, 30 motor, 50 compression mechanism part, 70 oil seal, 90 cavity, 100 rotary compressor.

Claims

A compression mechanism for compressing the refrigerant;
A crankshaft that transmits a rotational driving force to the compression mechanism;
A plain bearing having an inner diameter surface for slidably supporting the crankshaft;
A rolling bearing having an outer ring portion fixed to a groove provided on an inner diameter surface of the sliding bearing and an inner ring portion rotatably supported by the sliding bearing, the outer diameter surface of the crankshaft and the rolling bearing A rotary compressor having a clearance with the inner ring portion.
The rotary compressor according to claim 1, wherein the radial width of the clearance is 10 to 50 µm.