JP2014047969A - Oil separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil separator in which an area in a vessel is reduced while keeping a separation efficiency even if an amount of oil stored in the oil separator changes and an outflow of oil is restricted even in the case that a large amount of oil flows into the oil separator.SOLUTION: There is provided an oil separator having a cylindrical housing so as to separate oil from mixed fluid of refrigerant gas and oil mixed. The oil separator has an outflow pipe which sucks the refrigerant gas separated from the mixed fluid flowing into the cylindrical housing and dropping while being circulated at a suction port formed at its lower surface and flows it out from the lower surface in an upward direction. A wall surface above the suction port of the outflow pipe is formed with a suction hole from which the separated refrigerant gas is also sucked in.

Description

  The present invention relates to an oil separator that separates refrigerant gas and oil from a fluid mixture with refrigerant gas containing oil.

  There is a cyclone type oil separator using centrifugal force as means for separating a mixed fluid of refrigerant gas and oil into each fluid. In this cyclone type oil separator, the mixed fluid that flows in from the tangential direction of the inner wall surface of the cylindrical container descends while spirally swirling inside the container, while heavy oil collides with and adheres to the inner wall surface by centrifugal force. I will do it. Then, the oil separated from the refrigerant gas by the effect of centrifugal force moves to the lower part in the container by its own weight and is discharged from the bottom of the container to the outside, and the refrigerant gas is discharged upward from a pipe provided at the center of the cylinder.

  Since the cyclone type oil separator separates the refrigerant gas and the oil according to the principle as described above, the larger the area of the inner wall surface of the cylindrical container, the larger the area for separation, and the higher the separation efficiency of the oil separator. . However, when the amount of the oil separated in the lower part of the oil separator increases, the separation area is actually reduced, so that the separation efficiency is lowered. As an example, Japanese Patent Laid-Open No. 2002-61993 (Patent Document 1) discloses a component part of an oil separator whose purpose is to reduce fluctuations in separation efficiency when the amount of stored oil changes. When the refrigerant is trapped in the compressor of the outdoor unit on which the oil separator is mounted, a large amount of refrigerant flows into the oil separator and overflows to prevent it from flowing out of the cycle system. The intended refrigeration cycle apparatus is provided.

JP 2002-61993 A

  However, the oil separator mentioned above as an example needs an area in the container to maintain a separation efficiency above a certain level considering the volume of oil stored even when the amount of stored oil changes. Since it must be ensured above, the material cost increases.

  In addition, when the refrigerant has stagnated in the compressor of the outdoor unit equipped with the oil separator, the refrigerant has stagnated in order to prevent a large amount from flowing into the oil separator and overflowing to the outside of the cycle system. It is necessary to detect a state where the oil flows and to return the oil upstream of the compressor in the refrigeration cycle and to control the oil. However, if the state in which the refrigerant is sleeping cannot be detected or the circuit that returns oil fails, a large amount of oil flows out of the refrigeration cycle of the outdoor unit, leading to a high possibility of failure of the air conditioner. .

  Furthermore, if a large amount of oil is stored in the oil separator without overflowing, the refrigerant gas and oil mixed fluid swirls together with the refrigerant gas that has been separated during the swirling because there are few areas where the mixed fluid can swirl. Since the oil stored without being able to reduce the speed is disturbed and re-entrainment of the oil is induced, the separation efficiency is lowered. In addition, the mixed fluid of refrigerant gas and oil that has flowed into the oil separator descends while swirling the inner wall surface, so that the oil level near the wall surface is pushed to raise the oil level in the center. And since the distance between the suction port of the pipe for discharging the separated refrigerant gas and the oil level becomes small and it becomes easy to suck in the oil, the oil is refrigeration cycle of the outdoor unit equipped with the oil separator. It will flow out.

  Therefore, the present invention reduces the area in the container while maintaining the separation efficiency even when the amount of oil stored in the oil separator changes, and even when a large amount of oil flows into the oil separator. An object of the present invention is to provide an oil separator in which the amount of spillage is suppressed.

In order to solve the above problems, for example, the configuration described in the claims is adopted.
The present application includes a plurality of means for solving the above-mentioned problems. To give an example, “an oil separator that includes a cylindrical casing and separates oil from a mixed fluid in which refrigerant gas and oil are mixed”. A refrigerant gas separated from the mixed fluid flowing into the cylindrical casing and descending while swirling is sucked from a suction port formed on the lower surface, and an outflow pipe flowing upward from the lower surface is provided. And a suction hole is formed in the wall surface portion of the outflow pipe above the suction port, and the separated refrigerant gas is sucked from the suction hole.

  According to the present invention, even when the amount of oil stored in the oil separator changes, the area in the container is reduced while maintaining the separation efficiency, and even when a large amount of oil flows into the oil separator, It is possible to provide an oil separator that suppresses the outflow amount of the oil.

1 is a bird's eye view of an oil separator according to Embodiment 1. FIG. 1 is a plan view of an oil separator according to Embodiment 1. FIG. 1 is a front view of an oil separator according to Example 1. FIG. It is sectional drawing of the pipe | tube of the suction hole position provided in the pipe | tube lower part for making the separated refrigerant gas flow out of the oil separator which concerns on Example 1. FIG. It is a schematic diagram of the flow of the vicinity of the inner wall surface of the mixed fluid separated in the oil separator according to the first embodiment. It is a bird's-eye view of the pipe | tube lower part for making the refrigerant gas which the oil separator which concerns on Example 2 flows out flow out. It is a bird's-eye view of the pipe | tube lower part for making the refrigerant gas which the oil separator which concerns on Example 3 flows out flow out. It is a bird's-eye view of the pipe | tube lower part for making the refrigerant gas which the oil separator which concerns on Example 4 isolate | separates flow out.

  Hereinafter, embodiments will be described with reference to the drawings.

  The structure of the oil separator of the present invention as Example 1 is shown in FIGS. In addition, although not shown in figure, the oil separator of a present Example is mainly employ | adopted as an air conditioner. This air conditioner generally includes a compressor having a variable operating frequency, a four-way valve for switching between cooling operation and heating operation, an outdoor unit including an outdoor heat exchanger and an outdoor expansion valve, an indoor heat exchanger, An indoor unit including an indoor expansion valve, and a refrigerant pipe connecting the outdoor unit and the indoor unit are configured.

  The oil separator of this embodiment is provided on the discharge side of the compressor, and is provided in the oil return circuit for connecting the suction side pipe of the compressor and the oil separator, and the oil return pipe. An electronic expansion valve, a control means for controlling the opening frequency of the electronic expansion valve of the oil return circuit according to the operating frequency of the compressor and the pressure difference between the suction side and the discharge side of the compressor are provided.

  As shown in FIGS. 1, 2, and 3, the oil separator of the present embodiment includes a cylindrical container body 10 and upper and lower ends are provided with openings for an outflow pipe 40 and a discharge pipe 30 described later. The inflow pipe 20 is arranged in the tangential direction of the inner wall surface of the container main body 10, and the discharge pipe 30 is fixed to the lower opening of the container main body 10. A cylindrical outflow pipe 40 is inserted from the upper opening of the container body 10 into the inside so as to be coaxial with the central axis of the cylindrical portion of the container body 10. The through holes 50 are provided in the lower side wall surface of the outflow pipe 40 at equal intervals around the circumference of the pipe as shown in the sectional view of the pipe in FIG.

  That is, the inflow pipe 20 is arranged so that the mixed fluid flows in the intersecting direction so as to be almost perpendicular to the oil separator. The discharge pipe 30 discharges oil accumulated in the lower part of the container body 10 (housing). The outflow pipe 40 is disposed at a substantially central portion in the horizontal direction of the container main body 10 (housing), and the inflow pipe 20 is located on the side of the casing wall with respect to the outflow pipe 40 in the horizontal section of the container main body 10 (housing). Is to be arranged. That is, even if the inflow pipe 20 is extended as it is, it does not overlap the outflow pipe 40 but is arranged so as to be displaced.

  Next, a phenomenon that occurs in the oil separator having the above configuration will be described. A mixed fluid of refrigerant gas and oil flows into the container body 10 from the inflow pipe 20, and the mixed fluid descends while spirally turning around the wall surface inside the container body 10. The oil particles contained in the refrigerant gas subjected to the centrifugal force due to the swirling collide with and adhere to the wall surface in the container body 10 and are gradually separated from the refrigerant gas.

  FIG. 5 is a schematic diagram of the flow in the vicinity of the wall surface 11 of the container main body 10. The flow 60 of the mixed fluid that descends while swirling in this way is directed toward the lower side of the container, and the wall 61 is separated from the oil 61 and the container. The central portion changes into a three-layer flow 64 of a separated refrigerant gas flow 62 and an intermediate refrigerant gas / oil mixed fluid flow 63 that is not separated. Then, the oil separated from the refrigerant gas moves to the lower part of the container by its own weight and is discharged from the discharge pipe 30 or is stored for the amount not discharged. When oil is stored in the container, the above-described 60 flows 62 and 63 have less swirling regions. Then, when the oil stored in the lower part of the oil separator that has been stored without reducing the turning speed is reached, the oil level is disturbed, so that the oil 70 stored in the lower part of the oil separator is recycled. The refrigerant gas that is supposed to be scattered and separated is discharged from the outflow pipe 40.

  Here, in the present embodiment, the inside of the container body 10 is sucked through the hole 50 provided in the outflow pipe 40 while the container body 10 is swirling in the container like the separated refrigerant gas flow 62. Yes. That is, the oil separator of the present embodiment is a suction formed on the lower surface of the refrigerant gas separated from the mixed fluid flowing into the cylindrical housing (container body 10) and descending while turning on the wall surface. An outflow pipe 40 is provided which sucks from the mouth 41 and flows upward from the lower surface. In addition to the suction port 41 on the lower surface, a suction hole 50 is formed in the wall surface portion above the suction port 41 of the outflow pipe 40, and the separated refrigerant gas is sucked from the suction hole 50. In addition, as for the suction hole 50, as shown in FIG. 4, it is desirable to provide with two or more in the wall surface part above the suction inlet 41 of the outflow pipe 40. As shown in FIG.

  By adopting such a configuration, the turning speed can be reduced before reaching the oil level, and the disturbance of the oil stored in the lower part of the oil separator is further suppressed while maintaining the separation efficiency of the oil separator. Make it possible. Further, since the refrigerant gas 62 is sucked through the suction hole 50 provided in the wall surface of the outflow pipe, the amount of the refrigerant gas sucked from the suction port 41 on the lower surface is reduced, and as a result, is stored in the lower part in the oil separator. Even when the distance between the oil level 71 and the suction port 41 on the lower surface of the outflow pipe 40 for discharging the refrigerant gas to the outside of the oil separator becomes short, the oil becomes difficult to be sucked in, and the oil is separated directly from the outflow pipe. It is possible to suppress discharge to the outside of the vessel. Further, since the distance between the oil surface 71 and the suction port 41 on the lower surface of the outflow pipe 40 can be shortened and the container itself can be made smaller, the oil separator can be miniaturized and the material cost can be reduced. It becomes.

  In this embodiment, suction holes 51 are added in the vertical direction to the outflow pipe 40 of the first embodiment, and a bird's-eye view of the outflow pipe is shown in FIG. By providing the suction holes 51 in the vertical direction as well, the amount of suction of the separated refrigerant gas flow 62 is adjusted, and the swirl speed is sufficiently reduced before reaching the oil level 71, so that it is stored in the lower part of the oil separator. Oil disturbance can be suppressed.

  The present embodiment is holes 52, 53, 54 in which the area of the suction hole 50 is gradually reduced in the vertical direction from the bottom to the top with respect to the vertical suction hole provided in the outflow pipe 40 of the second embodiment. A bird's-eye view of the outflow pipe is shown in FIG. That is, the plurality of suction holes are formed in the wall surface portion of the outflow pipe 40 so that the lower side is larger than the upper side. Of the three-layer flow 64 described above, the oil 61 separated on the wall surface side and the refrigerant gas flow 62 separated on the central portion of the container as it goes downward in the container while flowing into the oil separator and turning. The flow 63 of the mixed fluid of refrigerant gas and oil, which gradually increases and the middle is not separated, decreases.

  Therefore, the lower part of the oil separator is maintained while maintaining the separation efficiency by increasing the area of the suction hole in the vertical direction of the outflow pipe 40 in accordance with the separated refrigerant gas flow 62 that gradually increases downward. Disturbance of the oil stored in can be suppressed.

  In this embodiment, not the suction hole but the slit 55 whose width is enlarged in the vertical direction is provided in the outflow pipe 40 of the first embodiment, and a bird's eye view of the outflow pipe is shown in FIG. The suction hole is a slit 55 formed on the wall surface portion of the outflow pipe 40 upward from the lower surface 41, and the slit 55 is larger in the wall surface portion of the outflow tube 40 on the lower side than on the upper side. Formed. As a result, the same effect as in the third embodiment can be obtained.

10 Container body 11 Wall surface 20 of container body 10 Inflow pipe 30 Outlet pipe 40 Outflow pipe 50 With respect to suction hole 5250 in the side wall surface of the outflow pipe added upward to suction hole 5150 in the lower side wall surface of the outflow pipe With respect to the suction hole 5352 on the side wall surface of the outflow pipe added in the upward direction by reducing the area of the hole, the suction hole 5453 on the side wall surface of the outflow pipe added in the upward direction by reducing the area of the hole The suction hole 55 on the side wall surface of the outflow pipe added in the upward direction by reducing the area of the hole 55 The suction slit 60 on the lower side wall surface of the outflow pipe 60 The flow of the mixed fluid 61 The oil 62 separated from the mixed fluid The state of the mixed fluid Remaining flow 63 Refrigerant gas flow separated from the mixed fluid 70 Oil 71 stored in the lower part of the oil separator Oil level stored in the lower part of the oil separator

Claims (6)

With a cylindrical housing,
An oil separator for separating oil from a mixed fluid in which refrigerant gas and oil are mixed,
The refrigerant gas separated from the mixed fluid flowing into the cylindrical housing and descending while swirling is sucked from the suction port formed on the lower surface, and includes an outflow pipe that flows upward from the lower surface,
An oil separator, wherein a suction hole is formed in a wall surface portion above the suction port of the outflow pipe, and the separated refrigerant gas is sucked also from the suction hole. The oil separator according to claim 1,
The oil separator, wherein a plurality of the suction holes are provided in a wall surface portion above the suction port of the outflow pipe. The oil separator according to claim 2,
The plurality of suction holes are formed in the wall surface of the outflow pipe so that the lower side is larger than the upper side. The oil separator according to claim 1,
The oil separator according to claim 1, wherein the suction hole is a slit formed in the wall surface portion of the outflow pipe upward from the lower surface. The oil separator according to claim 4,
The slit is formed so that the lower side is larger than the upper side in the wall surface portion of the outflow pipe. In the oil separator in any one of Claims 1-5,
An inflow pipe through which the mixed fluid flows in a direction crossing the oil separator;
A discharge pipe for discharging oil accumulated in the lower part of the housing,
The outflow pipe is disposed at a substantially central portion in the horizontal direction of the casing,
The oil separator according to claim 1, wherein the inflow pipe is disposed closer to the housing wall surface than the outflow pipe in a horizontal section of the housing.