JP6486217B2 - Compressor and refrigeration cycle apparatus - Google Patents

Description

  The present invention relates to a compressor including a cyclonic oil separator that separates oil (refrigeration oil) from refrigerant gas discharged from the compressor, and a refrigeration cycle apparatus including the compressor.

  Some refrigeration cycle devices such as air conditioners use a cyclone type oil separator provided on the compressor outlet side, or use a screw compressor integrally provided with a cyclone type oil separator (see, for example, Patent Document 1). . In such a screw compressor, a substantially cylindrical vertical cyclone oil separator is used to reduce the oil rate of the compressor (the amount of oil flowing out of the compressor). In this cyclone type oil separator, the oil is attached to the wall surface by centrifugal force induced by the swirling flow in the separation space, and the attached oil descends while rotating along the inner wall and is stored in the oil sump provided at the lower part. . The refrigerant gas from which the oil has been separated is discharged from the upper part of the cyclonic oil separator and supplied to the refrigeration cycle.

JP 2004-232669 A

  In a refrigeration cycle apparatus including a cyclonic oil separator as described in Patent Document 1, a check valve is provided on the discharge side of the cyclonic oil separator, and refrigerant gas compressed through the check valve is condensed in the refrigeration cycle. The refrigerant gas is prevented from flowing back by being sent out to the container side. In the case of a large flow rate such as a screw compressor, a lift type check valve is often used as a check valve.

  By providing a lift type check valve, the pressure in the separator rises due to the compressed refrigerant gas discharged from the cyclone type oil separator, and if the pressure exceeds the pressure downstream of the check valve, the valve body of the check valve Lifted and opened. When the compressor mechanism is operated in reverse due to the differential pressure between the low pressure gas and high pressure gas remaining inside the compressor due to the stop of the compressor, etc., and the pressure in the oil separator becomes smaller than the pressure downstream of the check valve, Falls downward and seats on the valve seat, thereby closing the valve and preventing the backflow of the refrigerant gas. Note that a stopper (for example, a retaining ring) is provided on the inner surface of the cylinder on which the valve body slides to limit the rising position of the valve body.

  In such a cyclonic oil separator, the refrigerant gas and the refrigerating machine oil are separated by centrifugal force by the swirling flow, and the swirling flow flows into a lift check valve provided on the outlet side of the cyclonic oil separator. At this time, the valve body of the lift type check valve rises while rotating and comes into contact with the retaining ring, and the ascending position of the valve body is regulated, but the valve body slides with the retaining ring while rotating by the swirling flow. Therefore, it turned out that the problem which a valve body wears arises.

  For such a problem, a rectifier can be provided to prevent the check valve from rotating. At this time, newly providing a rectifier at the separator outlet causes the product to be enlarged. Further, in order to prevent an increase in pressure loss, if an attempt is made to secure the passage area of the check valve and the rectifier, the check valve and the rectifier increase in size, which further increases the size of the product.

  The present invention provides a refrigeration cycle apparatus that suppresses the wear of a valve body of a check valve to ensure reliability and suppresses an increase in the size of a cyclonic oil separator including a check valve and the like. Let it be an issue.

The compressor of the present invention includes a compression mechanism section that compresses refrigerant, a refrigerant disposed at the downstream side of the compression mechanism section, an outer cylinder and an inner cylinder positioned inside the outer cylinder, and refrigerant discharged from the compression mechanism section. A cyclone type oil separator that separates the refrigerant into gas refrigerant and oil, a rectifier that is disposed at or inside the inlet of the inner cylinder and decelerates the swirling component of the refrigerant, and a check valve disposed downstream of the rectifier; The check valve is disposed inside the inner cylinder, and the refrigerant discharged from the compression mechanism flows into the cyclone oil separator and swirls down along the inner wall of the outer cylinder to turn into gas refrigerant and oil. Then, the separated gas refrigerant flows into the inner cylinder from the lower end of the inner cylinder, is discharged from the cyclone oil separator through the inner cylinder, and the separated oil flows along the inner wall surface of the outer cylinder. Flow down.

  According to the present invention, a refrigeration cycle apparatus that ensures the reliability of the product by suppressing the wear of the valve body of the check valve and suppresses the enlargement of the cyclonic oil separator including the check valve and the like. Can be provided.

Refrigeration cycle system diagram of refrigeration cycle equipment Explanatory drawing explaining the relationship between a cyclone type oil separator, a rectifier, and a check valve and their configurations The perspective view explaining the example of the assembly structure of a cyclone type oil separator, a rectifier, and a check valve The perspective view explaining other examples of the assembly structure of a cyclone type oil separator, a rectifier, and a check valve The perspective view explaining other examples of the assembly structure of a cyclone type oil separator, a rectifier, and a check valve The perspective view explaining other examples of the assembly structure of a cyclone type oil separator, a rectifier, and a check valve

  The compressor of the present invention includes a compression mechanism section that compresses refrigerant, a refrigerant disposed at the downstream side of the compression mechanism section, an outer cylinder and an inner cylinder positioned inside the outer cylinder, and refrigerant discharged from the compression mechanism section. A cyclone type oil separator that separates the refrigerant into gas refrigerant and oil, a rectifier that is disposed at or inside the inlet of the inner cylinder and decelerates the swirling component of the refrigerant, and a check valve disposed downstream of the rectifier; The refrigerant discharged from the compression mechanism flows into the cyclonic oil separator and is separated into gas refrigerant and oil by swirling down along the inner wall of the outer cylinder, and then the separated gas refrigerant is at the lower end of the inner cylinder The oil flows into the inner cylinder from the portion, is discharged from the cyclone oil separator via the inner cylinder, and the separated oil flows down along the inner wall surface of the outer cylinder. According to the compressor of the present invention, since the rotation of the check valve can be suppressed by the rectifier and the wear can be suppressed, the reliability of the product can be ensured. Furthermore, by incorporating the flow straightener inside the cyclone oil separator, the space inside the cyclone oil separator inner cylinder can be used effectively, and the size of the cyclone oil separator including the check valve can be increased. Can be suppressed.

  Hereinafter, specific examples of a compressor of the present invention and a refrigeration cycle apparatus including the compressor will be described with reference to the drawings.

  FIG. 1 is a refrigeration cycle system diagram of the refrigeration cycle apparatus of the present embodiment. A present Example demonstrates the case where it is an air conditioner as a refrigerating-cycle apparatus.

  The refrigeration cycle apparatus includes a compressor 1, a cyclonic oil separator 2 disposed on the discharge side of the compressor 1, a heat source side heat exchanger 5, a decompression device 6 such as an electronic expansion valve, and a use side heat exchanger 7. In the present embodiment, a cyclone oil separator 2 is separately installed on the discharge side of the compressor 1, and a lift check valve 4 is provided inside the cyclone oil separator 2 via a rectifier 3. The blower 8 supplies outdoor air to the heat source side heat exchanger 5.

  The high-temperature and high-pressure refrigerant gas compressed by the compressor 1 rises inside the inner cylinder of the oil separator after the oil is separated by the cyclonic oil separator. Thereafter, the refrigerant gas passes through the rectifier 3 and the lift check valve 4, is discharged from the upper part of the oil separator, and flows into the heat source side heat exchanger 5. The refrigerant exchanges heat with the outdoor air blown from the blower 8 in the heat source side heat exchanger 5 to condense, and then decompresses and expands in the decompression device 6 to become a gas-liquid two-phase flow, thereby using the heat exchanger on the use side. 7 flows in. In the use side heat exchanger 7, the temperature of the cold water is lowered by exchanging heat with the cold water supplied by circulation, and the refrigerant evaporates to become a refrigerant gas, which is again sucked into the compressor 1. As described above, the refrigerant circulates to constitute a refrigeration cycle.

  Next, with reference to FIG. 2, the relationship between the cyclone oil separator 2, the rectifying device 3, and the lift check valve 4 shown in FIG.

  In the present embodiment, a lift type check valve 4 is attached to a space inside the inner cylinder of the cyclonic oil separator 2 via a rectifier 3. The lift type check valve 4 has a differential pressure ΔP (= Pin−) between the pressure (Pin) of the compressed refrigerant gas that rises in the inner cylinder of the cyclonic oil separator 2 and the pressure (Pout) on the downstream side of the valve body. When Pout) becomes larger than zero and the weight of the valve body 4a is overcome, the valve body 4a is lifted and opened. Further, due to the stop of the compressor 1 or the like, the compression mechanism section is operated in reverse by the differential pressure between the low pressure gas and the high pressure gas remaining in the compressor, and the pressure in the oil separator 2 is lower than the pressure downstream of the check valve 4. When it becomes smaller, the valve body 4a drops downward and closes by being seated on the valve seat 4b. By providing such a lift type check valve 4, the backflow of the refrigerant gas is prevented.

  Conventionally, the inner surface of the cylinder on which the valve body 4a slides is provided with a retaining ring (stopper) for restricting the raised position of the valve body 4a. In this embodiment, the check valve 4 is a cyclone type. By installing it inside the oil separator, the upper discharge flange 9 is used as a stopper to determine the upper limit position of the valve body when the valve is opened.

  As indicated by a dotted arrow A, the high-temperature and high-pressure refrigerant gas compressed and discharged by the compression mechanism of the compressor 1 flows into a flow path formed by the outer cylinder 10 and the inner cylinder 11 of the cyclonic oil separator 2. And turns into a swirling flow. That is, the mixture of the refrigerant gas and the oil flows along the cylindrical inner wall of the oil separator 2 and flows along the inner wall to form a swirling flow. When the mixture of the refrigerant gas and the oil becomes a swirling flow, the oil in the refrigerant gas is separated from the refrigerant gas by the centrifugal separation action. As shown by the dotted arrow B, the separated oil flows downward along the cylindrical inner wall and returns to the compressor 1 through the oil reservoir 12. Further, the refrigerant gas from which the oil has been separated (only the refrigerant gas or the refrigerant gas having a small amount of oil) is discharged from the upper part of the cyclone type oil separator 2 while being swirling.

  Here, in the conventional refrigeration cycle apparatus, the rectifier 3 is not arranged on the upstream side of the lift check valve 4 as in the present embodiment. For this reason, when the swirling flow of the refrigerant gas discharged from the cyclonic oil separator 2 acts on the valve body 4a and slides with the retaining ring while the valve body 4a rotates, wear powder (iron powder) Etc.) occurs. When the wear powder flows into the refrigeration cycle and flows into the decompression device 6 such as an electronic expansion valve through the condenser, there is a possibility of causing the malfunction of the decompression device 6. In addition, when the refrigeration cycle apparatus includes a four-way valve, wear powder may flow into the sliding portion of the four-way valve, causing a malfunction of the four-way valve. Further, if the wear powder flows into the heat exchangers 5 and 7 and accumulates, there is a possibility that the heat exchange performance is deteriorated or the refrigerant flow path is clogged.

  Therefore, in this embodiment, the rectifier 3 and the check valve 4 are installed in the space inside the inner cylinder of the cyclonic oil separator 2, and the lift check valve 4 is provided on the downstream side of the rectifier 3. Further, a discharge flange 9 having a discharge port is disposed downstream of the check valve. By arranging the rectifier 3 and the check valve 4 in the inner cylinder inside the oil separator, a flow obtained by rectifying the swirl flow inside the inner cylinder is caused to flow through the check valve 4.

  The inner cylinder 11 partitions a swirling flow including oil flowing downward on the outer side of the inner cylinder and an ascending flow without oil flowing upward on the inner side of the inner cylinder. The space inside the inner cylinder serves as a flow passage for leading to the discharge port.

  Here, by arranging the rectifier and check valve in the inner cylinder space inside the oil separator, the rectifier and check valve are included compared to the case where the check valve and rectifier are externally attached to the oil separator outlet. The overall height of the oil separator is lowered. Accordingly, since the overall height of the chiller unit in which the oil separator is installed and stored can be reduced, the length of the pipe connected to the discharge port can also be shortened. Further, since the overall height of the chiller unit housing can be reduced, the material cost can be reduced and the manufacturing cost can be reduced.

  Furthermore, by incorporating a check valve, the overall height does not change even if the stroke length of the valve is changed, so that the piping connected to the chiller unit casing and discharge port can be shared.

  In order to reduce the pressure loss at the check valve inlet / outlet, it is necessary to enlarge the passage that flows around the outer periphery of the valve body by sizing the valve body of the check valve in the radial direction. Along with this, the piping needs to be increased in size. However, since the check valve is built in and the discharge flange 9 having the discharge port is provided on the downstream side of the check valve, the size of the check valve in the radial direction can be determined without changing the pipe diameter. Therefore, the pressure loss between the check valve inlet and outlet can be reduced without increasing the discharge pipe diameter.

  In addition, since the retaining ring used for the stopper is generally made of a material having high hardness such as piano wire, the valve body is significantly worn when the valve body is made of casting or carbon steel having low hardness. Therefore, a discharge flange 9 having a discharge port is provided on the downstream side of the check valve so that the check valve side end surface of the discharge flange 9 serves as a stopper of the valve body (the discharge flange 9 serving as a stopper and the valve body) The hardness is preferably comparable.) By comprising in this way, a retaining ring can be abolished and the unilateral abrasion of a valve body can be suppressed.

  Further, by providing a rectifier on the upstream side of the check valve disposed in the inner cylinder, the swirling flow that has flowed into the inner cylinder can be rectified before flowing into the check valve. Therefore, since the turning of the valve body can be suppressed and the wear of the valve body can be suppressed, the generation of wear powder can be suppressed.

  Next, examples of other structures of the cyclonic oil separator 1, the rectifier 3, and the check valve 4 shown in FIGS. 1 and 2 will be described with reference to FIGS.

  The rectifier 3 provided on the upstream side of the check valve may be provided at the inlet of the inner cylinder 11 or may be attached to the check valve suction port inside the inner cylinder 11. In FIG. 3, the rectifier 3 is arranged at the inlet of the inner cylinder 11. Since the rectifying device 3 can be disposed over the entire inlet opening of the inner cylinder 11, the pitch between the rectifying grids is widened, and the pressure loss between the rectifying grid entrances and exits can be kept low.

  In FIG. 4, the rectifier 3 provided on the upstream side of the check valve is installed in connection with the check valve 4 inlet. Since the outer diameter of the rectifying device 3 only needs to be equal to or larger than the diameter of the check valve 4 suction port, the rectifying device 3 can be reduced in size. In addition, as the rectifier 3, the structure comprised so that the space where a refrigerant | coolant flows in the rectifier may be divided with a partition plate, for example is employable. If the partition plate is configured in a cross shape, the space flowing through the rectifier 3 can be divided into four. Further, if the partition plate is formed in a lattice shape, it can be divided into a larger number of spaces. By dividing the flow path into a plurality of partitions by the partition plate and forming, for example, four or more spaces, one flow swirling in the inner cross section of the inner cylinder 11 on the upstream side of the rectifying device 3 passes through the swirling device 3. A plurality of swirl flows swirling in the space partitioned by the partition plate. By finely dividing the swirl flow that collides with the side surface of the valve body and gives the rotational driving force, the valve body passes through the valve body without applying the rotational driving force to the valve body, and therefore the rotation of the valve body can be suppressed.

  Furthermore, since the straightening device 3 provided on the upstream side of the check valve is provided in the inner cylinder 11, even if the thickness of the straightening device 3 is adjusted to adjust the straightening section, the total length of the oil separator 2 does not change. In addition, it is possible to share the piping connected to the casing and the discharge port of the chiller unit. In addition, since the rectifying device 3 is disposed in the inner cylinder 11, a sealing member is not required between the rectifying device 3 and the body 4c, so that the refrigerant gas does not leak into the outside air from the joint surface.

  Here, if it comprises as FIG. 4, the pitch between the rectification | straightening grids of the rectifier 3 will become narrow, and the pressure loss between rectification | straightening grid entrances will become large. Therefore, as shown in FIGS. 5 and 6, the inner cylinder 14 having a diameter larger than the inner diameter of the check valve suction port is further arranged inside the inner cylinder 11, and the rectifier 3 is arranged at the inlet of or inside the inner cylinder 14. To do. Since the diameter of the rectifying device 3 is larger than the diameter of the suction port 4d provided in the body 4c of the check valve 4 and smaller than the outer diameter of the body 4c of the check valve 4, the pitch between the rectifying grids can be set. The pressure loss between the rectifier 3 entrance and exit can be reduced. Here, the diameter of the rectifier 3 can be set to an arbitrary size according to the diameter of the inner cylinder 14.

  Further, since the swirling flow immediately after passing through the rectifying device 3 has a difference in the flow velocity of the swirling flow for each space divided by the partition plate, if the check valve 4 is arranged immediately after passing through the rectifying device 3, the valve body 4a is The valve body 4a moves irregularly in the radial direction, and a collision sound is generated when the valve body 4a hits the inner surface of the body 4c that houses the valve body 4a. Therefore, as shown in FIGS. 3, 5, and 6, the cylinder 14 is disposed between the suction port 4 d and the rectifying device 3. The plurality of swirling flows that have passed through the swirling device 3 repeatedly collide and mix in the cylinder 14, so that the swirling flow is broken and the direction of the flow is diffused, and the flow velocity of the radial component of the flow path cross section becomes uniform. Therefore, the behavior of the valve body 4a is stabilized, and the collision sound that the valve body 4a hits the inner surface of the body 4c can be suppressed.

  Furthermore, the outer diameter of the cylinder 14 can be attached in a range larger than the diameter of the suction port 4d provided in the body 4c of the check valve 4 and smaller than the outer diameter of the body 4c of the check valve 4. In FIG. 6, the outer diameter of the cylinder 14 and the outer diameter of the body 4c are the same. Since the cylinder 14 is attached to the upstream side of the body 4c, the swirling flow and the rising flow can be partitioned by the cylinder 14, and therefore the inner cylinder can be eliminated.

  In this embodiment, the rectifying device 3 and the check valve 4 are separately manufactured and installed inside the cyclone type oil separator 2. However, the check valve 4 and the rectifying device 3 may be integrated. Good. If comprised in this way, a number of parts can be decreased and an assembly can be performed more easily.

  As described above, according to this embodiment, by providing the rectifier 3 inside the cyclone type oil separator 2, the swirling flow of the refrigerant gas is changed to a straight flow or a flow closer to the straight flow, so that the check valve 4 Can flow into. Therefore, it can suppress that the valve body 4a of the non-return valve 4 rotates, and the valve body 4a wears. Further, since the check valve 4a and the rectifying device 3 are incorporated inside the cyclone oil separator rather than outside the cyclone oil separator, the space inside the inner cylinder 11 can be used effectively, so that the size of the product is increased. Reliability can be improved without doing so.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, although a screw compressor is used as the compressor 1 in the present embodiment, the compressor 1 is not limited to the screw compressor, and may be another type of compressor. Moreover, the cyclone type oil separator 2 is not limited to the one provided separately from the compressor, and the present invention can be applied to a case where the compressor and the cyclone type oil separator are integrated. Furthermore, although the present Example demonstrated using an air conditioner as a refrigeration cycle apparatus, it can apply to refrigeration cycle apparatuses, such as a chiller unit and a refrigerator.

1: Compressor (screw compressor)
2: Cyclone oil separator 3: Rectifier 4: Check valve (lift check valve)
4a: Valve body 4b: Valve seat 4c: Body 4d: Suction port 5: Heat source side heat exchanger 6: Pressure reducing device 7: Usage side heat exchanger 8: Blower
9: Discharge flange 9a: Discharge flange lower surface 10: Outer tube 11: Inner tube 12: Oil reservoir 13: Flat plate 14: Tube

Claims (4)

A compression mechanism for compressing the refrigerant;
A cyclonic oil separator that is disposed on the downstream side of the compression mechanism section, has an outer cylinder and an inner cylinder located inside the outer cylinder, and separates refrigerant discharged from the compression mechanism section into gas refrigerant and oil;
A rectifier that is disposed at or in the inlet of the inner cylinder and decelerates the swirling component of the refrigerant;
A check valve disposed downstream of the rectifier;
With
The check valve is disposed inside the inner cylinder;
Refrigerant discharged from the compression mechanism flows into the cyclonic oil separator, and is separated into gas refrigerant and oil by swirling down along the inner wall of the outer cylinder,
Thereafter, the separated gas refrigerant flows into the inner cylinder from the lower end portion of the inner cylinder, and is discharged from the cyclonic oil separator through the inner cylinder,
The separated oil flows down along the inner wall surface of the outer cylinder. In claim 1,
A compressor in which the rectifying device is disposed with a clearance from the check valve. In claim 2 ,
A cylindrical member having a diameter larger than the diameter of the suction port of the check valve inside the inner cylinder,
A compressor in which the rectifying device is disposed at or inside the cylindrical member. A refrigeration cycle apparatus comprising the compressor according to any one of claims 1 to 3 , a heat source side heat exchanger, a decompression device, and a use side heat exchanger.

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