Patent Description:
Cooling systems cycle a refrigerant to cool various spaces. For example, a refrigeration system may cycle refrigerant to cool spaces near or around a refrigeration unit. As another example, an air conditioning system may cycle refrigerant to cool a room.

Cooling systems cycle a refrigerant (e.g., carbon dioxide refrigerant) to cool various spaces. For example, a refrigeration system may cycle refrigerant to cool spaces near or around a refrigeration unit. As another example, an air conditioning system may cycle refrigerant to cool a room. These systems may include an oil separator that separates an oil that was introduced into the refrigerant (e.g., by a compressor). Conventional oil separators may present several disadvantages. For example, some oil separators require extra room to service the oil separators (e.g., to replace a core of the oil separator). As another example, some oil separators may cause a large pressure drop to occur in the system. As yet another example, some oil separators have limited capacity and/or require extra space for a separate oil reservoir to store separated oil.

This invention contemplates an unconventional oil separator with a vertical design. The oil separator according to the present invention has the features of claim <NUM>.

Generally, a refrigerant enters the vertical oil separator and spins downwards The oil separator includes plates within the oil separator that either maintain the spin of the refrigerant or reverse the spin of the refrigerant, which causes oil in the refrigerant to separate from the refrigerant. A vertical outlet allows refrigerant that spins towards the bottom of the oil separator to travel back towards the top and out of the oil separator. Separated oil is collected at the bottom of the oil separator. In this manner, the oil separator has a higher capacity and lower pressure drop than conventional designs. Additionally, the oil separator occupies less space than conventional designs for an oil reservoir, because the oil collects in the bottom of the oil separator. Furthermore, servicing the oil separator requires less room than certain conventional designs. Certain embodiments of the oil separator are described below.

According to the invention, an oil separator includes a vertical body, a first plate, a second plate, an inlet, and an outlet. The first plate is positioned within the vertical body. The first plate defines a first chamber within the vertical body. The second plate is positioned within the vertical body. The second plate and the first plate define a second chamber within the vertical body. The second plate further defines a third chamber within the body. The second chamber is below the first chamber. The third chamber is below the second chamber. The inlet directs a refrigerant into the vertical body and into the first chamber. The inlet is positioned to cause rotation of the refrigerant in the first chamber in a first direction about a longitudinal axis of the vertical body. The first plate directs the refrigerant in the first chamber into the second chamber such that the refrigerant in the second chamber rotates in the first direction about the longitudinal axis of the vertical body and downwards towards the second plate. The second plate directs the refrigerant in the second chamber into the third chamber such that the refrigerant in the third chamber rotates in a second direction about the longitudinal axis of the vertical body and downwards towards a bottom of the vertical body. The second direction is opposite the first direction. The outlet is positioned along the longitudinal axis of the vertical body. The outlet directs the refrigerant in the third chamber upwards through the first and second chambers and out of the vertical body.

According to the invention, a method includes directing, by an inlet, a refrigerant into a first chamber of a vertical body such that the refrigerant in the first chamber rotates in a first direction about a longitudinal axis of the vertical body. The first chamber is defined by a first plate positioned in the vertical body. The method also includes directing, by the first plate, the refrigerant in the first chamber into a second chamber of the vertical body such that the refrigerant in the second chamber rotates in the first direction about the longitudinal axis of the vertical body. The second chamber is defined by the first plate and a second plate positioned in the vertical body. The second chamber is below the first chamber. The method further includes directing, by the second plate, the refrigerant in the second chamber into a third chamber of the vertical body such that the refrigerant in the third chamber rotates in a second direction about the longitudinal axis of the vertical body. The second direction is opposite the first direction. The third chamber is below the second chamber. The method also includes directing, by an outlet positioned along the longitudinal axis of the vertical body, the refrigerant in the third chamber upwards through the first and second chambers and out of the vertical body.

According to a further embodiment of the present invention, a system includes a high side heat exchanger, a low side heat exchanger, a compressor, and an oil separator according to claim <NUM>. The high side heat exchanger removes heat from a refrigerant. The low side heat exchanger uses the refrigerant to remove heat from a space proximate the low side heat exchanger. The compressor compresses the refrigerant from the low side heat exchanger. The oil separator separates an oil from the refrigerant from the compressor. The oil separator includes a vertical body, a first plate, a second plate, an inlet, and an outlet. The first plate is positioned within the vertical body. The first plate defines a first chamber within the vertical body. The second plate is positioned within the vertical body. The second plate further defines a third chamber within the body. The second chamber is below the first chamber. The third chamber is below the second chamber. The inlet directs the refrigerant into the vertical body and into the first chamber. The refrigerant in the first chamber rotates in a first direction about a longitudinal axis of the vertical body. The first plate directs the refrigerant in the first chamber into the second chamber such that the refrigerant in the second chamber rotates in the first direction about the longitudinal axis of the vertical body and downwards towards the second plate. The second plate directs the refrigerant in the second chamber into the third chamber such that the refrigerant in the third chamber rotates in a second direction about the longitudinal axis of the vertical body and downwards towards a bottom of the vertical body. The second direction is opposite the first direction. The outlet is positioned along the longitudinal axis of the vertical body. The outlet directs the refrigerant in the third chamber upwards through the first and second chambers and out of the vertical body.

Certain further embodiments of the present invention may provide one or more technical advantages. For example, an embodiment of the oil separator has a higher capacity and lower pressure drop relative to conventional designs because of its vertical and centrifugal design. As another example, an embodiment of the oil separator occupies less space than conventional designs by integrating an oil reservoir into the oil separator. As yet another example, an embodiments of the oil separator uses less room than certain conventional designs during servicing. Certain embodiments may include none, some, or all of the above technical advantages. One or more other technical advantages may be readily apparent to one skilled in the art from the claims included herein.

For a more complete understanding of the present invention, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:.

Embodiments of the present invention and its advantages are best understood by referring to <FIG> of the drawings, like numerals being used for like and corresponding parts of the various drawings.

This disclosure contemplates an unconventional oil separator with a vertical design. Generally, a refrigerant enters the vertical oil separator and spins downwards. The oil separator includes plates within the oil separator that either maintain the spin of the refrigerant or reverse the spin of the refrigerant, which causes oil in the refrigerant to separate from the refrigerant. A vertical outlet allows refrigerant that spins towards the bottom of the oil separator to travel back towards the top and out of the oil separator. Separated oil is collected at the bottom of the oil separator. In this manner, the oil separator has a higher capacity and lower pressure drop than conventional designs. Additionally, the oil separator takes less space than conventional designs for an oil reservoir, because the oil collects in the bottom of the oil separator. Furthermore, servicing the oil separator requires less room than certain conventional designs. The oil separator will be described in more detail using <FIG>.

<FIG> illustrates an example cooling system <NUM> with an oil separator <NUM>. As shown in <FIG>, system <NUM> includes a high side heat exchanger <NUM>, a flash tank <NUM>, a low side heat exchanger <NUM>, a compressor <NUM>, and an oil separator <NUM>. System <NUM> may include any number of high side heat exchangers <NUM>, flash tanks <NUM>, low side heat exchangers <NUM>, compressors <NUM>, and oil separators <NUM>. Generally, system <NUM> cycles a refrigerant (e.g., carbon dioxide refrigerant) to cool a space.

High side heat exchanger <NUM> removes heat from a refrigerant. When heat is removed from the refrigerant, the refrigerant is cooled. This disclosure contemplates high side heat exchanger <NUM> being operated as a condenser and/or a gas cooler. When operating as a condenser, high side heat exchanger <NUM> cools the refrigerant such that the state of the refrigerant changes from a gas to a liquid. When operating as a gas cooler, high side heat exchanger <NUM> cools gaseous refrigerant and the refrigerant remains a gas. In certain configurations, high side heat exchanger <NUM> is positioned such that heat removed from the refrigerant may be discharged into the air. For example, high side heat exchanger <NUM> may be positioned on a rooftop so that heat removed from the refrigerant may be discharged into the air. As another example, high side heat exchanger <NUM> may be positioned external to a building and/or on the side of a building.

Flash tank <NUM> stores refrigerant received from high side heat exchanger <NUM>. This disclosure contemplates flash tank <NUM> storing refrigerant in any state such as, for example, a liquid state and/or a gaseous state. Refrigerant leaving flash tank <NUM> is fed to low side heat exchanger <NUM>. In some embodiments, a flash gas and/or a gaseous refrigerant is released from flash tank <NUM>. By releasing flash gas, the pressure within flash tank <NUM> may be reduced.

Refrigerant may flow from flash tank <NUM> to low side heat exchanger <NUM>. When the refrigerant reaches low side heat exchanger <NUM>, the refrigerant removes heat from the air around low side heat exchanger <NUM>. As a result, the air is cooled. The cooled air may then be circulated such as, for example, by a fan to cool a space such as, for example, a freezer and/or a refrigerated shelf. As refrigerant passes through low side heat exchanger <NUM>, the refrigerant may change from a liquid state to a gaseous state as it absorbs heat.

Refrigerant may flow from low side heat exchanger <NUM> to compressor <NUM>. Compressor <NUM> compresses the refrigerant to increase the pressure of the refrigerant. As a result, the heat in the refrigerant may become concentrated and the refrigerant may become a high pressure gas. Compressor <NUM> may then send the compressed refrigerant to oil separator <NUM>.

Compressor <NUM> may contain oil. The oil may mix with refrigerant passing through compressor <NUM>, and exit compressor <NUM>. Loss of oil may cause compressor <NUM> to degrade. Oil in the refrigerant passing through system <NUM> may also reduce the overall efficiency of the cooling system <NUM>. For example, oil may enter high side heat exchanger <NUM> with the refrigerant, and cause high side heat exchanger <NUM> to remove heat from the refrigerant less efficiently.

Oil separator <NUM> removes oil from the refrigerant of system <NUM>. In certain embodiments, removing oil from the flow of refrigerant in system <NUM> prevents reductions in efficiency of the system. For example, removing oil from the refrigerant may prevent oil from entering high side heat exchanger <NUM> with the refrigerant, which may cause high side heat exchanger <NUM> to remove heat from the refrigerant less efficiently. Oil separator <NUM> may be of any suitable size, shape, and capacity to remove oil from the flow of refrigerant.

Conventional oil separators may present several disadvantages. For example, some oil separators require extra room to service the oil separators (e.g., to replace a core of the oil separator). As another example, some oil separators may cause a large pressure drop to occur in the system. As yet another example, some oil separators have limited capacity and/or require extra space for a separate oil reservoir to store separated oil.

Oil separator <NUM> includes an unconventional, vertical design that may address some of these disadvantages. Generally, a refrigerant enters oil separator <NUM> and spins downwards. Oil separator <NUM> includes plates within oil separator <NUM> that either maintain the spin of the refrigerant or reverse the spin of the refrigerant, which causes oil in the refrigerant to separate from the refrigerant. A vertical outlet allows refrigerant that spins towards the bottom of oil separator <NUM> to travel back towards the top and out of oil separator <NUM>. Separated oil is collected at the bottom of oil separator <NUM>. In this manner, oil separator <NUM> has a higher capacity and lower pressure drop than conventional designs in certain embodiments. Additionally, oil separator <NUM> takes less space than conventional designs for an oil reservoir in certain embodiments, because the oil collects in the bottom of oil separator <NUM>. Furthermore, servicing oil separator <NUM> requires less room than certain conventional designs in particular embodiments. <FIG> illustrate certain aspects of oil separator <NUM>. <FIG> describes a process of operating oil separator <NUM>.

<FIG> illustrates oil separator <NUM> of system <NUM> of <FIG>. As seen in <FIG>, oil separator <NUM> includes a body <NUM>, an inlet <NUM>, plates <NUM> and <NUM>, an outlet <NUM>, meshes <NUM> and <NUM>, a drain <NUM>, an outlet <NUM>, and sight glasses <NUM>. Generally, oil separator <NUM> separates an oil from a refrigerant by spinning the refrigerant down the inside of oil separator <NUM>. Oil separator <NUM> changes the direction of the spin partway down oil separator <NUM>, which may cause additional oil to be separated from the refrigerant. The separated oil is collected at the bottom of oil separator <NUM> and the refrigerant is directed through the top of oil separator <NUM>. In certain embodiments, the vertical design of oil separator <NUM> allows oil separator <NUM> to have a higher capacity and lower pressure drop than conventional designs. Furthermore, by collecting oil at the bottom of oil separator <NUM>, oil separator <NUM> occupies less space than conventional designs, which include a separate oil reservoir. Furthermore, the design of oil separator <NUM> results in less room being needed to service oil separator <NUM> relative to conventional designs.

Oil separator <NUM> includes body <NUM> that is vertical. As seen in <FIG>, body <NUM> forms the largest and primary structure of oil separator <NUM>. Generally, refrigerant enters body <NUM> near the top of body <NUM>. Refrigerant then rotates downwards towards the bottom of body <NUM>. This rotation causes an oil in the refrigerant to separate from the refrigerant and drop to the bottom of body <NUM>. The oil is collected at the bottom of body <NUM> and the refrigerant is directed towards the top of body <NUM> to exit body <NUM>.

Body <NUM> may be any suitable shape. For example, body <NUM> may be a cylindrical shape and/or a rectangular shape. Body <NUM> includes a longitudinal axis <NUM> that extends along the vertical length of body <NUM>. Certain components of body <NUM> are positioned along longitudinal axis <NUM>. The rotation of the refrigerant within body <NUM> may be about longitudinal axis <NUM>. Longitudinal axis <NUM> runs along the vertical length of body <NUM> from the top surface of body <NUM> to the bottom surface of body <NUM>.

Inlet <NUM> is coupled to body <NUM> near the top surface of body <NUM>. Inlet <NUM> may be a pipe or a tube that directs refrigerant into body <NUM>. For example, inlet <NUM> may direct refrigerant from compressor <NUM> into body <NUM>.

Plates <NUM> and <NUM> are positioned within body <NUM> about longitudinal axis <NUM>. Plates <NUM> and <NUM> may be coupled to body <NUM> such that plates <NUM> and <NUM> are flush with the edges of body <NUM>. In this manner, refrigerant within body <NUM> may not flow around plates <NUM> and <NUM>, between the edges of plates <NUM> and <NUM> and body <NUM>. As discussed later using <FIG>, plates <NUM> and <NUM> include holes that allow refrigerant to flow through plates <NUM> and <NUM>.

As seen in <FIG>, plate <NUM> is positioned above plate <NUM> in body <NUM>. Plate <NUM> defines a first chamber <NUM> within body <NUM>. Plates <NUM> and <NUM> define a second chamber <NUM> within body <NUM>. Plate <NUM> defines a third chamber <NUM> within body <NUM>. Chamber <NUM> is positioned above chambers <NUM> and <NUM>. Chamber <NUM> is positioned above chamber <NUM>. Generally, refrigerant in body <NUM> rotates within chambers <NUM>, <NUM> and <NUM> such that an oil separates from the refrigerant.

Refrigerant enters chamber <NUM> through inlet <NUM>. After refrigerant enters chamber <NUM>, the refrigerant begins to rotate around chamber <NUM> about longitudinal axis <NUM>. The initial rotation is caused by the positioning of inlet <NUM> and the entry velocity of the refrigerant. When the refrigerant hits a wall of body <NUM>, the refrigerant begins to rotate about longitudinal axis <NUM>. In the example of <FIG>, the refrigerant rotates in a counterclockwise direction about longitudinal axis <NUM> in chamber <NUM>. As more refrigerant is directed into chamber <NUM> by inlet <NUM>, the rotating refrigerant is pushed downwards towards plate <NUM>.

Plate <NUM> is coupled to the edges of body <NUM> such that plate <NUM> is flush with the edges of body <NUM>. As a result, refrigerant in chamber <NUM> cannot flow around plate <NUM>, between the edges of plate <NUM> and body <NUM>. As discussed previously, plate <NUM> includes holes that direct the refrigerant from chamber <NUM> into chamber <NUM>. These holes may be angled to maintain the rotational direction of the refrigerant. As a result, the refrigerant in chamber <NUM> may rotate in the same direction as the refrigerant in chamber <NUM> about longitudinal axis <NUM>. In the example of <FIG>, the refrigerant in chamber <NUM> rotates in a counterclockwise direction about longitudinal axis <NUM>. The refrigerant also continues moving downwards towards plate <NUM>. In certain embodiments, the holes in plate <NUM> reduce the surface area (e.g., relative to the cross-sectional area of body <NUM>) through which the refrigerant in chamber <NUM> passes to chamber <NUM>. As a result, the velocity of the refrigerant increases as the refrigerant flows through the holes of plate <NUM>. This increase in velocity allows the refrigerant to continue rotating downwards through chamber <NUM>.

Refrigerant in chamber <NUM> rotates downwards towards plate <NUM>. Plate <NUM> is positioned in body <NUM> below plate <NUM>. Plate <NUM> may be coupled to the edges of body <NUM> such that plate <NUM> is flush with the edges of body <NUM>. As a result, refrigerant in chamber <NUM> cannot flow around plate <NUM>, between the edges of plate <NUM> and body <NUM>. As discussed previously, plate <NUM> includes holes through which the refrigerant in chamber <NUM> can flow to chamber <NUM>. The holes in plate <NUM> are angled in an opposite direction relative to the holes in plate <NUM>. As a result, the holes in plate <NUM> reverse the direction of rotation of the refrigerant. In the example of <FIG>, plate <NUM> reverses the direction of rotation of the refrigerant such that the refrigerant entering chamber <NUM> rotates in a clockwise direction about longitudinal axis <NUM>. In certain embodiments, this reversal in the direction of rotation may cause additional oil to be separated from the refrigerant. Furthermore, as discussed previously, the holes in plate <NUM> reduce the surface area (e.g., relative to the cross-sectional area of body <NUM>) through which the refrigerant flows from chamber <NUM> to <NUM>. As a result, the velocity of the refrigerant increases as the refrigerant flows through the holes of plate <NUM>, which allows the refrigerant to continue flowing downwards through chamber <NUM>.

According to the present invention, the refrigerant rotates in the first and second chambers <NUM> and <NUM> in a first same direction about a longitudinal axis <NUM>, and rotates in the third chamber <NUM>, in a second direction, opposite to the first direction, about the longitudinal axis <NUM>, downwards towards a bottom of the vertical body <NUM>. For example, the refrigerant in chambers <NUM> and <NUM> may rotate about longitudinal axis <NUM> in a clockwise direction, and the refrigerant in chamber <NUM> may rotate about longitudinal axis <NUM> in a counterclockwise direction. The angle of the holes in plates <NUM> and <NUM> are reversed to provide this opposite direction of rotation down body <NUM>.

Mesh <NUM> may be positioned within chambers <NUM> and <NUM> to separate or filter an oil out from the refrigerant. Mesh <NUM> may be coupled to the sidewalls of body <NUM> in chambers <NUM> and <NUM>. As the refrigerant rotates downwards through chambers <NUM> and <NUM> the refrigerant may interact or pass through mesh <NUM>. As the refrigerant passes through mesh <NUM>, mesh <NUM> may capture an oil from the refrigerant. The captured oil may then flow down towards the bottom of body <NUM>.

Mesh <NUM> is positioned within chamber <NUM> near the bottom of body <NUM>. In the example of <FIG>, mesh <NUM> may be positioned about longitudinal axis <NUM>. Outlet <NUM> may be positioned within mesh <NUM>. As the refrigerant in chamber <NUM> rotates downwards, the refrigerant may pass through mesh <NUM> on its way to outlet <NUM>. Mesh <NUM> may capture or filter out an oil in the refrigerant as the refrigerant passes through mesh <NUM>. The separated oil may then flow towards the bottom of body <NUM>.

Outlet <NUM> is positioned along longitudinal axis <NUM>. Outlet <NUM> begins in chamber <NUM> and extends upwards through chamber <NUM> and <NUM>. Outlet <NUM> extends through the top surface of body <NUM> to direct refrigerant away from oil separator <NUM> (e.g., to high side heat exchanger <NUM>). Refrigerant in chamber <NUM> passes through mesh <NUM> and into outlet <NUM>. The refrigerant then rises upwards through outlet <NUM> and away from oil separator <NUM> (e.g., to high-side heat exchanger <NUM>).

Oil <NUM> that is separated from the refrigerant is collected at the bottom of body <NUM>. In this manner, body <NUM> acts as an oil reservoir. Because the oil reservoir is effectively integrated with body <NUM>, oil separator <NUM> occupies less space than conventional oil separator designs that include a separate oil reservoir. The collected oil <NUM> may be removed from body <NUM> through drain <NUM> and/or outlet <NUM>. For example, drain <NUM> may be open to allow oil <NUM> to flow out of body <NUM> through drain <NUM>. As another example, oil <NUM> may be sucked out of body <NUM> through outlet <NUM>. The removed oil <NUM> may then be added back to other components of system <NUM> (e.g., compressor <NUM>).

Sight glasses <NUM> allow a person to look within chamber <NUM> to determine a level of oil <NUM> within chamber <NUM>. If a person determines that a level of oil within body <NUM> is too high, the person may extract the oil <NUM> using drain <NUM> and/or outlet <NUM>. In certain embodiments, sight glasses <NUM> may further include a level sensor that detects the level of oil <NUM> within body <NUM>. When the level of oil <NUM> in chamber <NUM> rises above a certain threshold, the level sensor may trigger an alert or warning (e.g., illuminating a light, communicating a message, etc.) so that a person can be made aware of the oil <NUM> level. In some embodiments, a separate oil extraction system may automatically activate to extract oil <NUM> from chamber <NUM> when the level sensor triggers.

<FIG> illustrates the configuration of certain components of oil separator <NUM>. As seen in <FIG> plate <NUM> is positioned above plate <NUM> and outlet <NUM> extends vertically through plates <NUM> and <NUM>. Plate <NUM> includes holes <NUM> that are angled in a first direction to maintain a direction of rotation of a refrigerant. Plate <NUM> includes holes <NUM> that are angled in a direction that is opposite holes <NUM>. In this manner, plate <NUM> and/or holes <NUM> reverse the direction of rotation of the refrigerant.

<FIG> illustrate the structure of plates <NUM> and <NUM>. <FIG> shows a top-down view of plates <NUM> and <NUM>. As seen in <FIG>, plates <NUM> and <NUM> may be a circular plate that includes holes <NUM> and/or <NUM> distributed around a perimeter of plates <NUM> and <NUM>. In some embodiments, holes <NUM> and/or <NUM> are tangential to the edge of plates <NUM> and <NUM>. Plates <NUM> and <NUM> and holes <NUM> and <NUM> may be any suitable shape (e.g., other than circular). For example, plates <NUM> and <NUM> may be rectangular to conform to a rectangular body <NUM>. Additionally, holes <NUM> and <NUM> may be rectangular and/or triangular. Refrigerant entering holes <NUM> and/or <NUM> are directed to rotate in a particular direction depending on the angle of holes <NUM> and/or <NUM>. In the examples of <FIG>, holes <NUM> are angled such that refrigerant flowing through holes <NUM> will rotate in a counterclockwise direction, and holes <NUM> are angled such that refrigerant flowing through holes <NUM> will rotate in a clockwise direction.

Plates <NUM> and <NUM> further include a hole <NUM> near the middle of plates <NUM> and <NUM>. Hole <NUM> allows outlet <NUM> to extend through plates <NUM> and <NUM> so that outlet <NUM> can extend to the top of oil separator <NUM>. As a result, refrigerant in oil separator <NUM> flows through outlet <NUM> through the centers of plates <NUM> and <NUM> enroute to exiting oil separator <NUM>.

<FIG> show a side-view of plates <NUM> and <NUM>. <FIG> shows a side-view of plate <NUM>. As seen in <FIG> holes <NUM> extend through plate <NUM> and are angled in a first direction. <FIG> shows a side-view of plate <NUM>. As seen in <FIG> holes <NUM> extend through plate <NUM> and are angled in a second direction that is opposite the direction of holes <NUM> in plate <NUM>.

<FIG> show embodiments that include an apparatus <NUM> coupled to one or more of plates <NUM> and <NUM>. Generally, apparatus <NUM> increases the velocity of the refrigerant in body <NUM> during low mass flow conditions. During low mass flow conditions, the refrigerant within body <NUM> may not have enough velocity for the refrigerant to rotate downwards (e.g., into chambers <NUM> and/or <NUM>) and up outlet <NUM>. Apparatus <NUM> may be included in oil separator <NUM> to further increase the velocity of the refrigerant during low mass conditions. Generally, apparatus <NUM> covers a portion of holes <NUM> and/or <NUM> to further reduce the cross-sectional area through which refrigerant can flow through plates <NUM> and/or <NUM>. As a result, the velocity of the refrigerant further increases as the refrigerant flows through plates <NUM> and/or <NUM>. Apparatus <NUM> includes a spring mechanism that compresses due to pressure from the refrigerant during high mass flow conditions. When compressed during high mass flow conditions, apparatus <NUM> covers less of holes <NUM> and/or <NUM>. As a result, apparatus <NUM> increases the cross-sectional area through which refrigerant flows through plates <NUM> and/or <NUM> as the velocity and/or pressure of the refrigerant increases.

<FIG> illustrates an embodiment where apparatus <NUM> is coupled to a top surface <NUM> of plate <NUM>. As seen in <FIG>, apparatus <NUM> includes a coupler <NUM>, a spring <NUM>, and a cover <NUM>. Coupler <NUM> couples apparatus <NUM> to plate <NUM>. For example, coupler <NUM> may include a screw that fastens apparatus <NUM> to top surface <NUM> of plate <NUM>. Coupler <NUM> may use any suitable fastener (e.g., bolt, nail, staple, adhesive, etc.) to secure apparatus <NUM> to plate <NUM>.

Spring <NUM> is coupled to coupler <NUM> and cover <NUM> is coupled to spring <NUM>. Generally, apparatus <NUM> is positioned on plate <NUM> such that cover <NUM> covers a portion of a hole <NUM> in plate <NUM>. By covering a portion of hole <NUM>, cover <NUM> further reduces the surface area through which the refrigerant passes through plate <NUM>. As a result, the velocity of the refrigerant further increases when cover <NUM> covers a portion of hole <NUM>. During low mass flow conditions, cover <NUM> covers a portion of hole <NUM> to further increase the velocity of the refrigerant flowing through hole <NUM>. When the low mass flow condition ends or during a high mass flow condition, the refrigerant has sufficient velocity and pressure to push on cover <NUM> and spring <NUM>. As a result, spring <NUM> compresses, cover <NUM> covers less of hole <NUM>, and the surface area through which the refrigerant passes through plate <NUM> increases. In this manner, apparatus <NUM> automatically adjusts for different mass flow conditions within body <NUM>.

<FIG> shows an alternative embodiment in which coupler <NUM> is coupled a bottom surface <NUM> of plate <NUM>. Coupler <NUM> may couple apparatus <NUM> to bottom surface <NUM> of plate <NUM>. Similar to the example of <FIG>, apparatus <NUM> covers a portion of hole <NUM> during low mass flow conditions. During high mass flow conditions the refrigerant pushes on cover <NUM> to compress spring <NUM> such that apparatus <NUM> covers less of hole <NUM>.

Although, <FIG> show apparatus <NUM> coupled to plate <NUM>, apparatus <NUM> may be coupled to any one of plates <NUM> and <NUM>. For example, apparatus <NUM> may be coupled to a top surface or a bottom surface of plate <NUM>. Additionally, each plate <NUM> and/or <NUM> may include any suitable number of apparatuses <NUM>. For example, each plate <NUM> and/or <NUM> may include one apparatus <NUM> for each hole <NUM> and/or <NUM>. As another example, each plate <NUM> and/or <NUM> may include one apparatus <NUM> for every other hole <NUM> and/or <NUM>. As yet another example, each plate <NUM> and/or <NUM> may include only one apparatus <NUM> that covers a portion of only one hole <NUM> and/or <NUM>.

<FIG> is a flowchart illustrating an example method <NUM> of operating oil separator <NUM> of the system <NUM> of <FIG>. Generally, various components of oil separator <NUM> perform the steps of method <NUM>. In particular embodiments, by performing method <NUM>, an oil is separated from refrigerant flowing through oil separator <NUM>.

Inlet <NUM> directs refrigerant into a first chamber <NUM> in step <NUM>. The refrigerant may be supplied by compressor <NUM>. As the refrigerant enters first chamber <NUM>, the refrigerant may rotate about a longitudinal axis <NUM> of oil separator <NUM>. For example, the refrigerant may rotate in a counterclockwise direction about longitudinal axis <NUM>. As more refrigerant enters first chamber <NUM> through inlet <NUM>, the rotating refrigerant may be pushed downwards towards a plate <NUM>.

In step <NUM>, plate <NUM> directs the refrigerant from the first chamber <NUM> into a second chamber <NUM>. Plate <NUM> may include holes <NUM> that are angled to maintain the direction of rotation of the refrigerant. In this manner, the refrigerant in the second chamber <NUM> may rotate about longitudinal axis <NUM> in the same direction as the refrigerant in first chamber <NUM>. The refrigerant in the second chamber <NUM> may rotate downwards towards a second plate <NUM>.

In step <NUM>, plate <NUM> directs the refrigerant from the second chamber <NUM> into a third chamber <NUM>. Plate <NUM> may include holes <NUM> that are angled in a direction that reverses the direction of rotation of the refrigerant. As a result, the refrigerant entering the third chamber <NUM> rotates about longitudinal axis <NUM> in a direction opposite from the direction of the refrigerant in chambers <NUM> and <NUM>. This reversal in the direction of rotation may cause additional oil to be separated from the refrigerant.

Outlet <NUM> directs refrigerant upwards in step <NUM>. Outlet <NUM> may direct the refrigerant in the third chamber <NUM> upwards through chambers <NUM> and <NUM>, and ultimately out oil separator <NUM>. Body <NUM> of oil separator <NUM> collects an oil separated from the refrigerant in step <NUM>. The oil may have been separated from the refrigerant in the second chamber <NUM> and the third chamber <NUM>. In certain embodiments, meshes <NUM> and <NUM> may separate additional oil from the refrigerant in chamber <NUM> and <NUM>. The separated oil is collected at the bottom of body <NUM>. As a result, an oil reservoir is effectively integrated with body <NUM>. In this manner, body <NUM> and oil separator <NUM> occupy less space than conventional designs that include an unintegrated oil reservoir.

Claim 1:
An oil separator (<NUM>) comprising:
a vertical body (<NUM>);
a first plate (<NUM>) positioned within the vertical body (<NUM>), the first plate (<NUM>) defining a first chamber (<NUM>) within the vertical body;
a second plate (<NUM>) positioned within the vertical body (<NUM>), the second plate and the first plate (<NUM>) defining a second chamber (<NUM>) within the vertical body (<NUM>), the second plate (<NUM>) further defining a third chamber (<NUM>) within the body (<NUM>), the second chamber (<NUM>) below the first chamber (<NUM>), the third chamber (<NUM>) below the second chamber (<NUM>);
an inlet (<NUM>) configured to direct a refrigerant into the vertical body (<NUM>) and into the first chamber(<NUM>), the inlet (<NUM>) being positioned to cause rotation of the refrigerant in the first chamber (<NUM>) in a first direction about a longitudinal axis (<NUM>) of the vertical body (<NUM>), the first plate (<NUM>) configured to direct the refrigerant in the first chamber (<NUM>) into the second chamber (<NUM>) such that the refrigerant in the second chamber rotates in the first direction about the longitudinal axis (<NUM>) of the vertical body (<NUM>) and downwards towards the second plate (<NUM>), the second plate (<NUM>) configured to direct the refrigerant in the second chamber (<NUM>) into the third chamber (<NUM>) such that the refrigerant in the third chamber (<NUM>) rotates in a second direction about the longitudinal axis (<NUM>) of the vertical body (<NUM>) and downwards towards a bottom of the vertical body (<NUM>), the second direction opposite the first direction;
an outlet (<NUM>) positioned along the longitudinal axis (<NUM>) of the vertical body (<NUM>), the outlet (<NUM>) configured to direct the refrigerant in the third chamber (<NUM>) upwards through the first and second chambers (<NUM>, <NUM>) and out of the vertical body (<NUM>).