JP2022148052A - Hermetic type rotary compressor and refrigerator using the same - Google Patents

Abstract

To allow oil separation from a refrigerant without discharging all of the refrigerant discharged from a compression mechanism unit into a closed container, and to supply oil to sliding portions of the compression mechanism unit by differential pressure oil supply.SOLUTION: A hermetic type rotary compressor includes a closed container, a compression mechanism unit that includes a cylinder, a roller, a crankshaft, and a bearing part for supporting the crankshaft, and a suction flow passage for sucking in a refrigerant into the cylinder. Further, the hermetic type rotary compressor includes a discharge port that is provided in the bearing part and discharges the refrigerant compressed in the cylinder, a discharge cover provided on the bearing part to cover the discharge port, a gas-liquid separation chamber that is formed by the bearing part and the discharge cover and in which the refrigerant compressed by the compression mechanism unit flows to separate the refrigerant and oil, a discharge pipe for discharging the refrigerant, from which the oil is separated in the gas-liquid separation chamber, to the outside of the compressor, and a communication passage that provides communication between the gas-liquid separation chamber and the inside of the closed container to let the oil separated in the gas-liquid separation chamber flow out to the outside of the closed container.SELECTED DRAWING: Figure 2

Description

The present invention relates to a hermetic rotary compressor used in a refrigeration cycle device such as a refrigerator and an air conditioner, and a refrigerator using the same, and is particularly suitable for a hermetic rotary compressor using a flammable refrigerant.

A hermetic rotary compressor used in refrigerators, air conditioners, etc. is disclosed in Japanese Patent No. 4020622 (Patent Document 1). In this patent document 1, an electric element and first and second rotary compression elements driven by the electric element are provided in a sealed container, and the refrigerant gas compressed by the first rotary compression element is sealed. The intermediate pressure refrigerant gas is discharged into the container, and the discharged intermediate pressure refrigerant gas is compressed by the second rotary compression element to set the pressure in the closed container to the intermediate pressure.

By the way, in recent years, flammable refrigerants such as isobutane (R600a) and R32, which are refrigerants with a low global warming potential (GWP), have been used as refrigerants used in refrigerators and air conditioners. In particular, isobutane, which is used in household refrigerators, is a highly flammable refrigerant, so there are strict restrictions on the amount of use, and the amount of refrigerant that can be enclosed in each refrigerator is limited to a very small amount. there is That is, technical standards are defined by the Electrical Appliance and Material Safety Law, and for example, the amount of isobutane used in household refrigerators is limited to 100 g or less.

Japanese Patent No. 4020622

As described above, when a combustible refrigerant is used as a refrigerant for refrigerators and air conditioners, it is required to minimize the amount of refrigerant charged in the refrigeration cycle.

When a hermetic rotary compressor is adopted as the refrigerant compressor used in the above refrigeration cycle, the hermetic rotary compressor uses lubricating oil (refrigerant gas) compressed in the compression mechanism to lubricate the sliding parts. Refrigerant oil (hereinafter also referred to as oil) is discharged into a closed container and separated from the oil. An oil reservoir is provided at the bottom of the sealed container to store lubricating oil for lubricating the sliding portion of the compression mechanism, and the oil discharged into the sealed container and separated is collected in the oil reservoir, The oil-separated refrigerant is sent to the refrigeration cycle.

Since the refrigerant compressed by the compression mechanism is discharged into the closed container of the closed rotary compressor, the inside of the closed container has a high-pressure atmosphere (discharge gas pressure). The higher the pressure, the more the refrigerant dissolved in the refrigerating machine oil is absorbed by the refrigerating machine oil. For this reason, when a closed rotary compressor is used as a refrigerant compressor for refrigerators and air conditioners, the amount of refrigerant dissolved in the refrigerating machine oil increases due to the high-pressure atmosphere inside the closed container. There was a problem that the number of

In the above Patent Document 1, rotary compression elements (cylinders, pistons, etc.) are provided in two stages, the refrigerant gas compressed by the first stage rotary compression element is discharged into a sealed container, and the discharged intermediate The pressurized refrigerant gas is compressed by the second-stage rotary compression element, so that the pressure inside the sealed container is set to an intermediate pressure. By adopting such a hermetic rotary compressor, the pressure inside the hermetic container can be set to an intermediate pressure lower than the discharge pressure. , it becomes possible to reduce the amount of refrigerant charged.

However, in Patent Document 1, the pressure of the refrigerant sucked into the second-stage rotary compression element is an intermediate pressure, which is the same as the pressure of the oil reservoir. Lubrication (differential pressure lubrication) is not possible, so it is necessary to install a gear pump (such as a trochoid pump) that can obtain sufficient lubrication pressure or a viscous pump that uses spiral grooves, etc., which makes the structure complicated and expensive. There is another issue.

An object of the present invention is to make it possible to separate oil from the discharged refrigerant without discharging all of the refrigerant discharged from the compression mechanism into a closed container, and to prevent oil from flowing into the sliding portion of the compression mechanism. An object of the present invention is to obtain a sealed rotary compressor and a refrigerator using the same, which can supply oil by differential pressure oil supply.

Another object of the present invention is to provide a closed type rotary compressor and a refrigerator using the same, which can reduce the amount of refrigerant dissolved in lubricating oil by lowering the pressure of the oil reservoir in the closed container below the discharge pressure. It's about getting

In order to achieve the above object, the first feature of the present invention is a closed container having an oil reservoir for storing lubricating oil, a cylinder provided in the closed container, a roller eccentrically rotated in the cylinder, A closed-type rotary compressor comprising a crankshaft for swinging the roller, a compression mechanism section having bearings for supporting the crankshaft, and a suction passage for sucking refrigerant into the cylinder of the compression mechanism section. a discharge port provided in the bearing portion for discharging the refrigerant compressed by the cylinder; a discharge cover provided in the bearing portion so as to cover the discharge port; and the bearing portion and the discharge cover. a gas-liquid separation chamber into which the refrigerant compressed by the compression mechanism flows and separates the refrigerant and oil; and a discharge pipe through which the refrigerant separated from the oil in the gas-liquid separation chamber is discharged outside the compressor and a communication passage that communicates between the gas-liquid separation chamber and the inside of the sealed container, and causes the oil separated in the gas-liquid separation chamber to flow out into the sealed container.

A second feature of the present invention is the hermetic rotary compressor described above, wherein the bearing portion includes a main bearing provided at an upper portion of the cylinder and a sub-bearing provided at a lower portion of the cylinder; A liquid separation chamber is formed so as to cover the discharge port formed in the main bearing and surround the crankshaft, and is provided in the communication passage to separate the pressure in the communication passage from the pressure in the sealed container. and an opening/closing device for opening and closing the communicating passage according to a pressure difference between the pressure in the communicating passage and the pressure in the sealed container. The pressure of the oil pool in which the lubricating oil is stored in the container is controlled to a pressure between the discharge pressure of the refrigerant discharged from the discharge passage and the suction pressure of the refrigerant sucked from the suction passage. It is characterized by

A third feature of the present invention is that it comprises a compressor, a condenser, an expansion valve, and an evaporator, uses isobutane (R600a) as a refrigerant to configure a refrigeration cycle, and creates cold air with the evaporator and stores it in the refrigerator. The refrigerator uses the closed rotary compressor as the compressor, and the amount of isobutane enclosed in the refrigerating cycle is 100 g or less.

According to the present invention, it is possible to separate the oil from the refrigerant discharged from the compression mechanism without discharging all of the refrigerant discharged from the compression mechanism into the sealed container, and at the same time, it is possible to separate the oil from the refrigerant discharged from the compression mechanism to the sliding portion of the compression mechanism. There is an effect that it is possible to obtain a hermetic rotary compressor and a refrigerator using the same, which can perform oil supply by differential pressure oil supply.

Further, according to the present invention having the second characteristic, the sealed rotary unit can further reduce the amount of refrigerant dissolved in the lubricating oil by reducing the pressure of the oil reservoir in the sealed container below the discharge pressure. There is an effect that a compressor and a refrigerator using the same can be obtained.

1 is a longitudinal sectional view showing Embodiment 1 of a hermetic rotary compressor of the present invention; FIG. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1; FIG. 2 is a partially enlarged view of part A in FIG. 1; FIG. 4 is a diagram illustrating the relationship between the pressure inside the closed container and the COP (coefficient of performance) of the compressor; FIG. 3 is a perspective view of only the main bearing shown in FIG. 2 as viewed obliquely from above; FIG. 2 is a view for explaining Example 2 of the present invention, and is a vertical cross-sectional view of a refrigerator equipped with a hermetic rotary compressor of the present invention.

Hereinafter, specific embodiments of the hermetic rotary compressor and the refrigerator using the same according to the present invention will be described with reference to the drawings. In each figure, the parts denoted by the same reference numerals are the same or corresponding parts.

A first embodiment of the hermetic rotary compressor of the present invention will be described with reference to FIGS. 1 to 5. FIG. The hermetic rotary compressor of this embodiment is used as a refrigerant compressor constituting a refrigeration cycle apparatus such as a refrigerator and an air conditioner.

1 is a longitudinal sectional view showing a first embodiment of the hermetic rotary compressor of the present invention, and FIG. 2 is a sectional view taken along the line II-II in FIG. The overall configuration will be described with reference to FIGS. 1 and 2. FIG.

In FIG. 1, 1 is a sealed container in which lubricating oil (refrigerating machine oil) is enclosed, 2 is an electric motor portion fixedly provided in the sealed container 1, and the electric motor portion 2 includes a stator 2a and a rotor 2b. It has A crankshaft 3 is integrally fixed to the rotor 2b of the electric motor section 2. As shown in FIG. Reference numeral 4 denotes a compression mechanism provided in the hermetically sealed container 1, and the compression mechanism 4 is driven by the electric motor 2 through the crankshaft 3. As shown in FIG.

The compression mechanism portion 4 includes a main bearing (bearing portion) 5 having a boss portion 5a that supports the electric motor portion 2 side of the crankshaft 3, and a sub bearing portion 6a that supports the lower side of the crankshaft 3. A bearing (bearing portion) 6 and a cylinder 8 sandwiched between the main bearing 5 and the sub-bearing 6 and integrally fixed with a fastening bolt 7 are provided.

The compression mechanism 4 includes a roller 9 which is accommodated in the cylinder 8 and driven to revolve by the eccentric rotation of an eccentric pin 3a formed on the crankshaft 3, and a roller 9 extending radially from the outer circumference of the roller 9. A vane (not shown) that moves in and out of a storage portion provided in the cylinder 8 according to the orbital motion (eccentric motion) of the roller 9 and a spring 10 (see FIG. 2) that presses the vane against the roller 9 are also provided. there is

Furthermore, a compression chamber (cylinder chamber) 11 is formed in the compression mechanism portion 4 by the cylinder 8 , the roller 9 , the vane, the main bearing 5 and the sub-bearing 6 . The main bearing 5 has a wall surface portion 5b that forms the wall surface of the compression chamber 11 on the side of the motor unit, and the sub-bearing 6 has a wall surface portion 6b that forms the wall surface of the compression chamber 11 on the side opposite to the motor unit. .

The compression mechanism 4 is also provided with a suction port (not shown) for drawing refrigerant gas into the compression chamber 11 . Refrigerant in the refrigeration cycle is introduced into the suction port through a suction pipe (suction flow path) 12 (see FIG. 2). Furthermore, as the roller 9 revolves in the cylinder 8, the sucked refrigerant is compressed in the compression chamber 11, and the refrigerant (refrigerant gas) compressed in the compression chamber 11 is discharged through a discharge port 25 (see FIG. 1). 5) is formed in the main bearing 5. As shown in FIG. Further, as shown in FIG. 2, a discharge valve (reed valve in this embodiment) 13 for opening and closing the discharge port 25 is provided on the main bearing 5 on the outlet side of the discharge port 25 .

The main bearing 5 is fixed to the sealed container 1 by welding or the like at its outer peripheral wall portion 5c. The cylinder 8 and the sub-bearing 6 are fixed to the main bearing 5 with the fastening bolts 7 .
Reference numeral 14 denotes a power terminal for supplying electricity to the electric motor portion 2;

Lubricating oil (refrigerating machine oil; oil) stored in the oil reservoir 15 passes through an oil supply passage 17 formed in the crankshaft 3 from an oil inflow portion 16 provided at the lower end of the crankshaft 3, and flows into the crankshaft 3. The sliding surfaces of the compression mechanism 4, such as the sliding surface between the main bearing 5 and the sub-bearing 6, the sliding surface between the eccentric pin 3a and the roller 9, the sliding surface between the roller 9 and the cylinder 8, and the vane, are different. Oiled by pressure. That is, in this embodiment, the pressure in the sealed container 1 is used to form a differential pressure oil supply passage for supplying oil to the sliding portion of the compression mechanism 4 having a lower pressure than the pressure in the sealed container 1 by means of the differential pressure. is doing.

In this embodiment, as shown in FIGS. 1 and 2, a discharge cover 18 is attached to the main bearing 5 by the fastening bolt 7 so as to cover the discharge port and the discharge valve 13 (on the side opposite to the compression chamber). It is fixed to the bearing 5 . A gas-liquid separation chamber (discharge passage) 19 is formed by the discharge cover 18 and the main bearing 5 , and the refrigerant compressed in the compression chamber 11 flows into the gas-liquid separation chamber 19 through the discharge port and the discharge valve 13 . discharged through the

The refrigerant discharged into the gas-liquid separation chamber 19 contains lubricating oil that lubricates the sliding portion of the compression mechanism 4, and pushes up the discharge valve 13 from the discharge port 25 to separate the gas and liquid. It is discharged into chamber 19 . The oil-containing refrigerant discharged into the gas-liquid separation chamber 19 collides with the wall surface of the discharge cover 18 forming the gas-liquid separation chamber, whereby the oil is separated from the refrigerant gas and propagates along the wall surface. It accumulates at the bottom of the gas-liquid separation chamber 19 . On the other hand, the compressed refrigerant gas from which the oil has been separated is sent through the discharge pipe 20 to the outside of the compressor, for example, to the refrigeration cycle of a refrigerator or the like.

As shown in FIG. 2, the gas-liquid separation chamber 19 is formed so as to surround the crankshaft 3, and the space on the one end side of the gas-liquid separation chamber 19 where the discharge valve 13 is provided. An opening 21a of a communication passage 21 (see FIG. 1) communicating with the inside of the sealed container 1 is formed on the other end side (terminal side) away from the . In addition, the portion of the discharge cover 18 where the fastening bolt 7 is provided is formed in a convex portion 18a that protrudes toward the inner diameter side. is narrowed. As a result, the oil-containing refrigerant discharged from the discharge port into the gas-liquid separation chamber 19 collides with the wall surface of the convex portion 18a forming the gas-liquid separation chamber 19 to efficiently separate the oil. there is

An inlet portion 20a of the discharge pipe 20 in the gas-liquid separation chamber 19 opens to a space in the gas-liquid separation chamber 19 on the opposite side from the discharge port 25 with the convex portion 18a interposed therebetween. The radial position of the inlet portion 20a is located on the outer diameter side of the inner diameter end portion of the convex portion 18a, and the refrigerant gas discharged from the discharge port and separated from the oil is discharged from the inlet portion 20a. It flows while bending toward 20a. Therefore, the refrigerant gas from which the oil has been separated flows into the discharge pipe 20 without mixing the separated oil again.

The center position of the inlet portion 20a of the discharge pipe 20 in the height direction is also arranged above the center of the gas-liquid separation chamber 19 in the height direction, and the lower end of the discharge pipe 20 is located in the gas-liquid separation chamber. By arranging it above the bottom of 19, it is possible to further enhance the effect of preventing re-mixing of oil into the refrigerant gas.

The bottom portion of the gas-liquid separation chamber 19 is formed so as to become deeper in a stepped or tapered shape toward the terminal side where the communication path 21 is arranged. As a result, the oil separated on the discharge valve 13 side of the gas-liquid separation chamber 19 can smoothly flow along the bottom of the gas-liquid separation chamber 19 toward the communicating passage 21 side. Although FIG. 2 shows that the bottom of the gas-liquid separation chamber 19 is formed stepwise toward the end side, it can be manufactured more easily than the case where the bottom is formed in a tapered shape.

2, reference numeral 23 denotes a communication hole that communicates the space above the compression mechanism 4 in the sealed container 1 and the space below the compression mechanism 4 on the side of the oil reservoir 15. In the example shown in FIG. , the communication holes 23 are provided at six locations on the outer peripheral side of the main bearing 5 and in the circumferential direction.

Next, the configuration around the communicating passage 21 in this embodiment will be described with reference to FIGS. 1 to 3. FIG. FIG. 3 is a partially enlarged view of part A in FIG.
As shown in FIGS. 1 to 3, a communicating passage 21 opening at the end of the gas-liquid separation chamber 19 is formed in the main bearing 5 in the radial direction, and the gas-liquid separation chamber 19 and the sealed container 1 are connected to each other. It is configured to communicate with the space.

Further, on the side of the opening of the communicating path 21 into the sealed container 1, the pressure in the communicating path 21 or the pressure in the gas-liquid separation chamber (discharge flow path) 19 and the pressure in the sealed container 1 are applied. An opening/closing device 22 is provided for opening and closing the communication passage 21 by the pressure difference between the two. The opening/closing device 22 adjusts the pressure of the oil reservoir 15 in which the lubricating oil of the sealed container 1 is stored to the discharge pressure of the refrigerant discharged from the gas-liquid separation chamber 19 through the discharge pipe 20 to the refrigerating cycle. , and the suction pressure of the refrigerant sucked into the compression mechanism 4 from the suction pipe (suction flow path) 12 (hereinafter also referred to as "intermediate pressure").

In this embodiment, the opening/closing device 22 is composed of a valve mechanism having a valve element 22a provided in the communicating passage 21 and a valve spring (elastic body) 22b for pressing the valve element 22a. The strength of the valve spring 22b is determined so that the valve body 22a opens when the differential pressure between the upstream side and the downstream side of the valve (differential pressure across the valve body) exceeds a certain value.

More specifically, the valve mechanism includes a valve seat 22c provided around the open end of the communication passage 21 on the closed container side, and a valve body 22a that contacts the valve seat 22c to open and close the communication passage 21. , a valve spring 22b that presses the valve body 22a toward the valve seat 22c, and a retainer 22d that holds the valve spring 22b and is fixed to the main bearing 5. As shown in FIG. The strength of the valve spring 22b is determined by the pressure of the oil reservoir 15 in which lubricating oil is stored, the discharge pressure which is the pressure in the communication passage 21 or the gas-liquid separation chamber 19, and the pressure in the compression mechanism 4. It is determined to be a pressure (intermediate pressure) between the suction pressure of the refrigerant to be used.

With this configuration, when the pressure difference between the pressure in the communication passage 21 or the gas-liquid separation chamber 19 and the pressure in the closed container 1 reaches a predetermined constant pressure difference, the valve of the valve mechanism The body 22a overcomes the pressing force of the valve spring 22b and leaves the valve seat 22c, and the communication passage 21 communicates with the inside of the sealed container 1. As a result, the oil separated in the gas-liquid separation chamber 19 is discharged from the communication passage 21 into the sealed container 1 and accumulated in the oil reservoir 15 . Further, when the valve body 22a opens, the pressure in the sealed container 1 increases, and when the pressure difference between the front and rear sides of the valve body 22a (the upstream side and the downstream side of the valve body) becomes smaller than a predetermined value, the valve spring 22b The valve body 22a is closed by a pressing force of . In this way, the valve body 22a opens and closes when the pressure difference across the valve body reaches a predetermined value. can be kept in the range of

According to this embodiment, the pressure in the sealed container 1 can be maintained at a pressure lower than the discharge pressure, that is, at an arbitrary intermediate pressure, so that the amount of refrigerant dissolved in the lubricating oil can be reduced. In addition, the amount of refrigerant required for refrigerating cycle operation can be increased by the amount that can reduce the amount of refrigerant dissolved in lubricating oil, and the amount of enclosed refrigerant can be reduced accordingly. Therefore, it is possible to realize a refrigeration cycle apparatus such as a refrigerator and an air conditioner that can reduce the amount of a highly flammable refrigerant such as isobutane or a flammable refrigerant such as R32.

Isobutane, which is highly flammable, is often used in household refrigerators, but there are strict restrictions on the amount of isobutane that can be used, and the amount of refrigerant that can be enclosed in each refrigerator is limited to a very small amount. there is For this reason, it has been difficult to adopt a sealed rotary compressor that requires a large amount of refrigerant, but by adopting the present invention, it becomes possible to adopt a highly efficient sealed rotary compressor.

In this embodiment, the pressure of the oil reservoir 15 in the sealed container 1 can be maintained at an arbitrary intermediate pressure higher than the suction pressure. It is also possible to supply each sliding part of the part 4 .

Thus, in this embodiment, the cylinder 8 and the roller 9 are one set of one cylinder system, that is, not multi-stage compression, but a single-stage compression type sealed rotary compressor, and the pressure in the sealed container 1 is the suction pressure. Any intermediate pressure between the discharge pressure can be realized. As a result, the amount of refrigerant dissolved in the lubricating oil can be reduced, and differential pressure oil supply to the compression mechanism portion 4 becomes possible. Therefore, it is possible to supply oil to the compression mechanism 4 with a simple configuration without using a complicated and expensive pump such as a gear pump or a viscous pump.

In the example of FIG. 1, a centrifugal type oil supply pump is also built in the oil supply passage 17 at the lower end of the crankshaft 3. However, in this embodiment, since differential pressure oil supply is possible, the centrifugal pump is not necessarily used. it's not necessary. In this embodiment, an oil supply pump having a simple structure is also provided as an aid for ensuring oil supply.

By adopting this embodiment, it becomes possible to control the pressure in the sealed container 1 within a desired arbitrary pressure range by adjusting the strength of the valve spring 22b. Here, when the pressure inside the sealed container 1 is high, the amount of refrigerant dissolved in the lubricating oil increases, so the amount of refrigerant sent to the refrigerating cycle decreases and the efficiency of the refrigerating cycle decreases. On the other hand, when the pressure inside the closed vessel 1 is low, the pressure difference between the compression chamber and the inside of the closed vessel increases, so that the leakage of compressed refrigerant from the compression mechanism portion increases. Further, since the pressing force of the spring 10 for pressing the vane against the roller 9 is increased, the friction loss is also increased.

Therefore, it was found that there is a relationship shown in the diagram of FIG. 4 between the pressure in the sealed container 1 and the coefficient of performance (COP) of the refrigeration cycle apparatus using the sealed rotary compressor. In FIG. 4, Ps is the suction pressure in the hermetic rotary compressor, and Pd is the discharge pressure.

From FIG. 4, in the closed rotary compressor, the opening/closing device (valve It has been found that by adjusting the strength of the valve spring 22b of the mechanism 22, a more efficient hermetic rotary compressor can be obtained. By applying this to refrigerators, air conditioners, etc., it is possible to realize a refrigeration cycle apparatus with a higher coefficient of performance.

In the description of the first embodiment, the strength of the valve spring 22b as the opening/closing device 22 is adjusted, and when the differential pressure between the upstream side and the downstream side of the valve body 22a reaches a certain value or more, the above-mentioned Although the example configured by the valve mechanism in which the valve element 22a is opened has been described, the present invention is not limited to this configuration. For example, pressure sensors measure the pressure (discharge pressure) on the side of the gas-liquid separation chamber 19, which is the pressure on the upstream side of the valve body 22a, and the pressure in the sealed container 1, which is the pressure on the downstream side of the valve body 22a. Alternatively, when the pressure difference exceeds a predetermined value, the control device may be configured to open and close the valve so as to open the communication passage 21 .

Furthermore, in the above-described embodiment, the pressure in the closed container 1 is set to an intermediate pressure between the suction pressure and the discharge pressure, but the present invention is not limited to such an embodiment. It can also be applied to those in which the pressure in 1 is almost the suction pressure. That is, by providing the gas-liquid separation chamber 19, it is possible to separate the oil from the discharged refrigerant without discharging all of the refrigerant discharged from the compression mechanism 4 into the sealed container. The separated oil can be returned to the closed container, and the refrigerant gas from which the oil has been separated can be sent to the refrigeration cycle. Further, it is possible to obtain a hermetic rotary compressor capable of supplying oil to the sliding portion of the compression mechanism portion 4 by differential pressure oil supply.

FIG. 5 is a perspective view (bird's-eye view) of only the main bearing 5 shown in FIG. 2 as viewed obliquely from above. In this figure, reference numeral 24 denotes a valve housing groove for housing the discharge valve 13 (see FIG. 2), and the valve housing groove 24 is formed with a discharge port 25 into which the refrigerant compressed in the compression chamber 11 flows. Above the discharge port 25, the discharge valve (reed valve) 13 for opening and closing the discharge port 25 is arranged as shown in FIG. A spring plate portion of the discharge valve 13 formed of a reed valve, a retainer for restricting upward movement of the discharge valve 13, and the like are also disposed in the valve housing groove 24. As shown in FIG.

The bottom portion of the gas-liquid separation chamber (discharge channel) 19 shown in FIG. The upper side of the bottom is covered with a discharge cover 18 shown in FIG. 1 to form the gas-liquid separation chamber 19 . A discharge pipe 20 indicated by a dashed line penetrates the outer peripheral wall portion 5c of the main bearing 5 and also penetrates the discharge cover 18 (see FIG. 1) to open into the gas-liquid separation chamber 19. As shown in FIG.

As shown in FIG. 5, the bottom of the gas-liquid separation chamber 19 is highest on the side of the discharge port 25 (on the side of the discharge valve 13). The provided part is the lowest. By forming the bottom portion deep in a stepped manner, the bottom portion of the gas-liquid separation chamber 19 is gradually lowered, and the oil separated from the refrigerant on the upstream side of the gas-liquid separation chamber 19 flows into the opening of the communication passage 21. It is made to flow smoothly toward the portion 21a. That is, the oil-containing refrigerant discharged from the discharge port 25 into the gas-liquid separation chamber 19 collides with the walls of the gas-liquid separation chamber 19, such as the convex portions 18a, so that the oil is separated. Since the refrigerant falls to the bottom of the gas-liquid separation chamber 19 and smoothly flows through the bottom of the gas-liquid separation chamber 19 as indicated by the white arrow in FIG. 5, mixing with the refrigerant gas can be suppressed.

Instead of forming the stepped shape, the bottom portion may be tapered to be lower. However, since the stepped shape facilitates manufacturing, the bottom portion is formed in the stepped shape in this embodiment. . 5, 5d is a bolt hole through which the fastening bolt 7 (see FIGS. 1 and 2) passes.

As shown in FIGS. 2 and 5, in this embodiment, the gas-liquid separation chamber 19 is formed so as to surround the boss portion 5a of the main bearing, and the portion through which the fastening bolt 7 penetrates is used. Since the discharge cover 18 is formed with a plurality of projections 18a, the refrigerant gas containing oil collides with the walls of the projections 18a and the like, and the oil is efficiently removed from the gas-liquid separation chamber 19. can be separated. A plurality of fastening bolts 7 for fastening the cylinder 8, the main bearing 5, and the sub-bearing 6 are arranged along the gas-liquid separation chamber 19, and accordingly, a plurality of the convex portions 18a are provided (Fig. In example 2, 3) are provided to enhance the oil separation effect.

Therefore, almost all of the discharge gas from the compression mechanism 4 is discharged into the closed container 1, the oil is separated in the closed container 1, and the refrigerant gas in the closed container 1 is sent to the refrigeration cycle. Refrigerant gas from which compressed oil is separated can be delivered directly from the gas-liquid separation chamber 19 in the discharge cover 18 to the refrigerating cycle without using a rotary compressor.

In addition, in this embodiment, almost all of the compressed refrigerant gas discharged from the compression mechanism 4 is not discharged into the sealed container 1, so the pressure in the sealed container 1 does not need to be the discharge pressure. The inside of the sealed container 1 can be set to a pressure (intermediate pressure) between the discharge pressure and the suction pressure by using the opening/closing device (valve mechanism) 22 (see FIGS. 1 and 3). Therefore, it is possible to reduce the amount of refrigerant to be charged and to supply oil to the compression mechanism 4 under a differential pressure.

In the first embodiment described above, the compression mechanism 4 of the hermetic rotary compressor 100 applies the present invention to a 1-cylinder system (single type) hermetic rotary compressor in which the cylinder 8 and the roller 9 are one set. Although the case has been described, the present invention is not limited to a one-cylinder hermetic rotary compressor. That is, the compression mechanism 4 can also be applied to a two-cylinder, single-stage hermetic rotary compressor having two pairs of cylinders 8 and rollers 9 . When the present invention is applied to this two-cylinder hermetic rotary compressor, a cylinder 8 and a roller 9 are arranged on both sides between the main bearing 5 and the sub-bearing 6 with a partition plate interposed therebetween. For the upper cylinder (compression element), the main bearing (upper bearing) is provided with a discharge cover 18 in the same manner as in the first embodiment. (Lower bearing) may be provided with a discharge cover similar to that of the first embodiment to form a gas-liquid separation chamber. Further, the oil separated in the gas-liquid separation chamber 19 may be introduced into the sealed container 1 through the communication passage 21 .

Next, a refrigerator, which is an example of equipment equipped with the hermetic rotary compressor according to the present invention, will be described. FIG. 6 is a longitudinal sectional view of a refrigerator 200 equipped with a hermetic rotary compressor (compressor) 100 according to the present invention.

Refrigerator 200 has heat insulating box body 201 . The compressor employs the closed-type rotary compressor 100 of the first embodiment described above, and is installed below the refrigerator 200, which is a refrigerating cycle device, in a region surrounded by the insulating box 201 and the partition 203. It is

By connecting the hermetic rotary compressor 100, a condenser composed of a heat radiation pipe, an expansion device composed of a capillary tube and an expansion valve, an evaporator composed of a cooler 202, etc., A refrigerating cycle using a volatile refrigerant is formed.

The refrigerator 200 has a refrigerator compartment 204, an upper freezer compartment 205, a lower freezer compartment 206, and a vegetable compartment 207 as an example of storage compartments. Cooling is provided by operating a cycle (not shown).

As mentioned above, home refrigerators often use highly flammable isobutane, but there are strict limits on the amount of use. That is, the amount of isobutane that can be enclosed in one refrigerator is limited to 100 g or less. For this reason, it has been difficult to adopt a hermetic rotary compressor, which generally requires a larger amount of refrigerant than a reciprocating compressor. It becomes possible to employ an efficient hermetic rotary compressor in a household refrigerator.

In FIG. 6, a refrigerator was described as an example of a device equipped with the sealed rotary compressor 100 according to the present invention. It can be applied to various refrigeration cycle devices such as cases.

Moreover, the present invention is not limited to the above-described embodiments, and includes various modifications.
Moreover, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment.
Furthermore, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the described configurations.

1: Closed container, 2: Electric motor part, 3: Crankshaft, 3a: Eccentric pin,
4: compression mechanism portion, 5: main bearing (bearing portion), 5b: wall portion, 5c: outer peripheral wall portion,
5d: bolt hole, 6: sub-bearing (bearing portion), 6a: boss portion, 6b: wall surface portion,
7: fastening bolt, 8: cylinder, 9: roller, 10: spring,
11: compression chamber, 12: suction pipe (suction flow path), 13: discharge valve,
14; power supply terminal, 15: oil reservoir, 16: oil inflow portion, 17: oil supply passage,
18: discharge cover, 18a: convex portion, 19: gas-liquid separation chamber (discharge channel),
20: discharge pipe, 20a: inlet, 21: communicating passage, 21a: opening,
22: opening and closing device (valve mechanism), 22a: valve body, 22b: valve spring (elastic body),
22c: valve seat, 22d: retainer,
23: communication hole, 24: valve accommodation groove, 25: discharge port,
100: Hermetic rotary compressor,
200: Refrigerator, 201: Thermal insulation box, 202: Cooler, 203: Partition,
204: refrigerator compartment, 205: upper freezer compartment, 206: lower freezer compartment, 207: vegetable compartment.

Claims (10)

A sealed container having an oil reservoir that stores lubricating oil;
a compression mechanism provided in the sealed container and including a cylinder, a roller that rotates eccentrically in the cylinder, a crankshaft that rocks the roller, and a bearing that supports the crankshaft;
A hermetic rotary compressor comprising a suction passage for sucking refrigerant into the cylinder of the compression mechanism,
a discharge port provided in the bearing portion for discharging refrigerant compressed by the cylinder;
a discharge cover provided on the bearing so as to cover the discharge port;
a gas-liquid separation chamber formed by the bearing portion and the discharge cover into which the refrigerant compressed by the compression mechanism portion flows to separate refrigerant and oil;
a discharge pipe for discharging the refrigerant from which the oil is separated in the gas-liquid separation chamber to the outside of the compressor;
a communication passage that communicates the gas-liquid separation chamber with the inside of the sealed container and causes the oil separated in the gas-liquid separation chamber to flow out into the sealed container;
A closed rotary compressor, comprising: 2. The hermetic rotary compressor according to claim 1, wherein the bearing unit includes a main bearing provided in the upper part of the cylinder and a sub-bearing provided in the lower part of the cylinder,
A hermetic rotary compressor, wherein the gas-liquid separation chamber is formed so as to cover the discharge port formed in the main bearing and surround the crankshaft. 3. The hermetic rotary compressor according to claim 2, further comprising an opening/closing device provided in said communicating passage for opening and closing said communicating passage according to a pressure difference between the pressure in said communicating passage and the pressure in said sealed container. A closed rotary compressor characterized by: 4. The hermetic rotary compressor according to claim 3, wherein the opening/closing device opens and closes the communication path according to the pressure difference between the pressure in the communication path and the pressure in the closed container, The pressure of the oil reservoir in which the lubricating oil is stored is controlled to a pressure between the discharge pressure of the refrigerant discharged from the gas-liquid separation chamber and the suction pressure of the refrigerant sucked from the suction passage. A closed rotary compressor characterized by: 5. The hermetic rotary compressor according to claim 4, wherein the opening/closing device comprises a valve provided in the communication passage and a valve mechanism having an elastic body that presses the valve. , wherein the strength of the elastic body is determined so that the valve opens when the differential pressure between the and the downstream side reaches a predetermined value or more. 3. The closed rotary compressor according to claim 2, wherein a discharge port and a discharge valve for opening and closing the discharge port are provided at one end of the gas-liquid separation chamber, and the other end of the gas-liquid separation chamber is sealed. The refrigerant discharged into the gas-liquid separation chamber collides between the space in which the discharge valve is arranged and the space in which the opening of the communication path is formed. A wall surface is provided to separate the lubricating oil mixed in the refrigerant from the refrigerant, and the oil-separated refrigerant is discharged outside the compressor from the discharge pipe, and the oil separated in the gas-liquid separation chamber is separated from the A hermetic rotary compressor characterized in that the fluid flows into a hermetic container through a communication passage. 7. The hermetic rotary compressor according to claim 6, further comprising fastening bolts for fastening the cylinder, the main bearing and the sub-bearing, wherein the fluid discharged from the discharge port into the gas-liquid separation chamber is The oil is separated by colliding with the wall surface of the discharge cover at the portion where the fastening bolt is provided, and the discharge pipe is placed in the space on the opposite side of the fastening bolt from the discharge port in the gas-liquid separation chamber. A hermetic rotary compressor, comprising an inlet, wherein refrigerant from which oil has been separated flows from the inlet into the discharge pipe and is discharged to the outside of the compressor. 8. The hermetic rotary compressor according to claim 7, wherein the inlet portion of the discharge pipe is provided at a position deviating from the flow direction of the separated oil to the outer peripheral side and on the upper side. Hermetic rotary compressor. 7. The hermetic rotary compressor according to claim 6, wherein the bottom portion of the gas-liquid separation chamber is configured to be deep in a stepped or tapered shape from the discharge valve side toward the opening of the communication passage. and forming a flow of the separated oil toward the opening of the communication passage. A refrigerator comprising a compressor, a condenser, an expansion valve, and an evaporator, using isobutane (R600a) as a refrigerant to form a refrigeration cycle, wherein the evaporator produces cold air and discharges it into the refrigerator, wherein the compression The sealed rotary compressor according to any one of claims 1 to 9 is used as a compressor, and the amount of isobutane enclosed in the refrigeration cycle is 100 g or less. refrigerator.

Images