Patent Description:
Generally, in a scroll compressor, compression chambers are formed while an orbiting scroll performs an orbiting motion relative to a fixed scroll or a non-orbiting scroll. The orbiting scroll is coupled to a rotational shaft to receive rotational force, but an anti-rotation mechanism is disposed between the orbiting scroll and a main frame or between the orbiting scroll and the non-orbiting scroll. Accordingly, the orbiting scroll performs an orbiting motion without rotation even when rotational force is transmitted.

Anti-rotation mechanisms are mainly classified into an Oldham ring type and a pin and ring type. For the Oldham ring type, keys formed at a ring are slidably coupled to an orbiting scroll and a member supporting the orbiting scroll with being interposed therebetween, to suppress rotation of the orbiting scroll. For the pin and ring type, a pin is coupled to a member supporting an orbiting scroll, and a ring into which the pin is pivotally inserted is disposed in the orbiting scroll, to suppress rotation of the orbiting scroll. Of course, in the pin and ring type, the positions of the pin and the ring may be arranged oppositely, but hereinafter, a type in which a ring is coupled to an orbiting scroll will be mainly described.

Patent Document <NUM> (US Patent Publication No. <CIT>) discloses a scroll compressor to which a pin and ring type is applied in a so-called 'hermetic compressor', in which a drive motor constituting a driving source is disposed inside a casing. In this case, a pin is inserted into a main frame and a ring is inserted into an orbiting scroll, with interposing a thrust plate between the main frame and the orbiting scroll.

Patent Document <NUM> (US Patent Registration No. <CIT>) discloses a scroll compressor to which a pin-and-ring type is applied in a so-called 'open compressor', in which a gas engine constituting a driving source is provided outside a casing to transmit driving force through a drive shaft exposed to the outside of the casing. In this case, a pin is inserted into an orbiting scroll and a ring is inserted into a front housing, with interposing a thrust plate between the front housing and the orbiting scroll.

However, since the related art anti-rotation ring as described above is completely embedded in a ring insertion groove of the orbiting scroll, the orbiting scroll is brought into close contact with the thrust plate or the orbiting scroll and the front housing (main frame) are brought into close contact with each other when the thrust plate is not provided. As a result, sufficient oil is not supplied to a bearing surface between the orbiting scroll and the thrust plate. This may cause wear due to an increase in friction loss or an occurrence of seizure on the bearing surface. This may occur more severely in a scroll compressor in which an oil separator is disposed at the exterior of a casing as well as a horizontal scroll compressor in which it is difficult to dispose an oil pump.

<CIT> discloses a scroll compressor having an anti-rotation mechanism capable of preventing rotation of an orbiting scroll. <CIT> discloses an oil-free type scroll type fluid machine which compresses and transfers a gas in a non-lubricated state. <CIT> discloses a compressor for automotives having an anti-rotation mechanism using a pin and a cylindrical element coupled to the pin. <CIT> discloses an improved rotation preventing means of a scroll compressor for preventing rotation of a movable scroll element and for permitting an orbital motion of the movable scroll element.

The present disclosure describes a scroll compressor, capable of suppressing seizure or/and friction loss between an orbiting scroll and a member facing the same when a pin and ring type anti-rotation mechanism is applied.

The present disclosure also describes a scroll compressor, capable of feeding oil smoothly between an orbiting scroll and a member facing the orbiting scroll.

The present disclosure further describes a scroll compressor, capable of securing a gap, through which oil can be introduced, by physically spacing an orbiting scroll apart from a member facing the orbiting scroll.

The present disclosure further describes a scroll compressor, capable of physically spacing an orbiting scroll apart from a member facing the orbiting scroll by using existing parts.

The present disclosure further describes a scroll compressor, capable of storing oil in a member by which an orbiting scroll is physically spaced apart from a member facing the orbiting scroll.

The present disclosure further describes a scroll compressor, capable of securing reliability of a member by which an orbiting scroll is physically spaced apart from a member facing the orbiting scroll.

In order to achieve those aspects and other advantageous of the subject matter disclosed herein, there is provided a scroll compressor according to the appended claim <NUM>.

An axial thickness of the ring body portion is larger than an axial depth of the ring insertion groove. This can allow the orbiting scroll and a member facing the same to be spaced physically apart without a separate member, to secure a gap for oil to flow, such that the oil can be smoothly supplied between the orbiting scroll and the member, thereby suppressing seizure or/and friction loss between the orbiting scroll and the member.

In one example, the axial thickness of the ring body portion may be smaller than or equal to twice the axial depth of the ring insertion groove. This can allow the orbiting scroll and the member facing the same to be appropriately spaced apart from each other, such that oil can be smoothly introduced between the orbiting scroll and the member and unstable behavior of the orbiting scroll can be suppressed.

In another example, the pin coupling portion may be disposed eccentrically from a center of the ring body portion. Accordingly, the anti-rotation pin can be coupled to a predetermined position of the anti-rotation ring, and the anti-rotation pin can perform an orbiting motion relative to the anti-rotation ring while effectively constraining a rotation of the orbiting scroll.

In another example, the pin coupling portion may be formed through both side surfaces of the ring body portion in the axial direction or recessed from any one of the body side surfaces by a preset depth. An inner diameter of the pin coupling portion may be larger than an outer diameter of the anti-rotation pin. With this configuration, the anti-rotation pin can be coupled to a predetermined position in the anti-rotation ring, and can perform the orbiting motion while sliding in the circumferential direction with respect to the anti-rotation ring.

Specifically, one end of the anti-rotation pin may be fixedly coupled to the scroll support member, and another end of the anti-rotation pin may be rotatably coupled to the pin coupling portion. As the anti-rotation pin is fixed to the scroll support member, the anti-rotation pin can be easily coupled to the anti-rotation ring.

In another example, the anti-rotation pin may integrally extend from the pin coupling portion. A pin insertion groove may be formed in the scroll support member such that the anti-rotation pin is rotatably coupled thereto. Since the anti-rotation pin and the anti-rotation ring are integrally formed with each other, an assembling process between the anti-rotation pin and the anti-rotation ring can be excluded, thereby facilitating assembling of an anti-rotation mechanism.

In another example, the ring body portion may be formed in a disk shape entirely blocked except for the pin coupling portion. This can increase a sliding area of the anti-rotation ring substantially defining an axial bearing surface, which can result in stably supporting the orbiting scroll and reducing surface pressure of the anti-rotation ring, thereby securing reliability.

Specifically, the ring body portion may entirely have the same thickness. This can uniformly maintain a bearing surface of the anti-rotation ring, thereby stabilizing a behavior of the orbiting scroll and further improving reliability of the anti-rotation ring.

According to the claimed invention a weight-reducing portion is disposed in the ring body portion at one side of the pin coupling portion. This can reduce a weight of the anti-rotation ring defining a substantial axial bearing surface, thereby improving efficiency of the compressor. In addition, oil can be stored in the weight-reducing portion so as to be quickly supplied between the orbiting scroll and the member facing the same when the compressor is turned on again.

Specifically, the ring body portion may include a reinforcing portion disposed between the weight-reducing portion and the pin coupling portion to surround the pin coupling portion. This can reduce a weight of the anti-rotation ring and stably support the anti-rotation pin.

More specifically, an area of the reinforcing portion may be smaller than or equal to an area of the weight-reducing portion. This can minimize a weight of the anti-rotation ring and stably support the anti-rotation pin.

The reinforcing portion may be formed as the weight-reducing portion is spaced apart from the pin coupling portion in a radial direction. An outer circumferential surface of the reinforcing portion may be formed as a curved surface having the same center as that of the pin coupling portion. This can minimize a width of the reinforcing portion while stably supporting the anti-rotation pin, thereby minimizing the weight of the anti-rotation ring.

Specifically, an outer diameter of the reinforcing portion may be twice larger than or equal to or four times smaller than or equal to an inner diameter of the pin coupling portion. This can optimize the reinforcing portion of the anti-rotation ring so as to minimize the weight of the anti-rotation ring and secure reliability of the anti-rotation ring including the reinforcing portion.

According to the claimed invention, the weight-reducing portion is formed through both side surfaces of the ring body portion in the axial direction, or recessed from one of the both side surfaces. This can minimize the weight of the anti-rotation ring including the pin coupling portion, and store oil in the anti-rotation ring, thereby effectively suppressing seizure and friction loss when the compressor is turned on again. This can reduce the weight of the anti-rotation ring including the pin coupling portion and enhance rigidity of the pin coupling portion. This can also lower surface pressure of the anti-rotation ring according to an installation direction of the ring body portion, to enhance reliability and stably support the orbiting scroll. Also, oil can be stored in the anti-rotation ring, so as to effectively suppress seizure and friction loss when the compressor is turned on again.

Specifically, an oil separator for separating oil from refrigerant discharged from the casing may be disposed outside the casing. An oil return pipe may be disposed to connect the oil separator and an inside of the casing. The oil return pipe may be connected to the inside of the casing at a position where the same faces a portion between the orbiting scroll and the scroll support member in a radial direction. When the oil separator is disposed outside the compressor, oil separated in the oil separator can be smoothly and quickly supplied to an axial bearing surface between the front housing and the orbiting scroll constituting a sliding part inside the compressor.

Description will now be given in detail of a scroll compressor according to exemplary embodiments disclosed herein, with reference to the accompanying drawings. A scroll compressor according to the present disclosure employs a pin-and-ring type anti-rotation mechanism, and a horizontal scroll compressor, which constitutes a typical air conditioning refrigeration cycle together with a condenser, an expander, and an evaporator, in a gas engine heat pump will be described as an example.

However, the present disclosure relates to a pin-and-ring type anti-rotation mechanism commonly applied to a scroll compressor and hence is not limited to the horizontal scroll compressor for the gas engine heat pump. In other words, the pin-and-ring type anti-rotation mechanism according to the present disclosure can be commonly applied to an orbiting scroll. In the case of the horizontal scroll compressor for the gas engine heat pump, however, a casing has a small volume and an installation of an oil pump is limited, which may make it difficult to feed oil into a gap between an orbiting scroll and a scroll support member supporting the orbiting scroll, compared to other types of compressors. Hereinafter, a horizontal scroll compressor for a gas engine heat pump will be mainly described.

<FIG> is a schematic view illustrating a gas engine heat pump in accordance with an embodiment of the present disclosure.

Referring to <FIG>, a gas engine heat pump <NUM> according to an embodiment includes a compressor <NUM>, a condenser <NUM>, an expander <NUM>, and an evaporator <NUM> which define a closed loop. That is, the condenser <NUM>, the expander <NUM>, and the evaporator <NUM> are sequentially connected to a discharge side of the compressor <NUM> and the evaporator <NUM> is connected to a suction side of the compressor <NUM>.

In this embodiment, an oil separator <NUM> to be described later is disposed at the discharge side of the compressor <NUM>, that is, between the compressor <NUM> and the condenser <NUM>. A first outlet side of the oil separator <NUM> is connected to a refrigerant circulation pipe <NUM> connected to the condenser <NUM>, and a second outlet side of the oil separator <NUM> is connected to an oil return pipe <NUM> that faces the suction side of the compressor <NUM>.

In the drawings, unexplained reference numeral <NUM> denotes a clutch assembly, and <NUM> denotes a refrigerant return pipe.

In the gas engine heat pump <NUM> as described above, refrigerant compressed in the compressor <NUM> is discharged toward the condenser <NUM>, after passing through the oil separator <NUM> located at an upstream side of the condenser <NUM>. Refrigerant and oil are separated in the oil separator <NUM>. The refrigerant sequentially passes through the refrigeration cycle including the condenser <NUM>, the expander <NUM>, and the evaporator <NUM> and is suctioned back into the compressor <NUM>, while the oil returns to the compressor <NUM> from the oil separator <NUM> through the oil return pipe <NUM> without passing through the refrigeration cycle.

However, the oil return pipe <NUM> may be connected to (joined together with) the refrigerant suction pipe <NUM> to be connected to the suction side of the compressor <NUM>, but this may increase a specific volume of refrigerant suctioned into a compression chamber V as described above, thereby lowering volumetric efficiency of the compressor. Therefore, in this embodiment, it is advantageous to dispose the oil return pipe <NUM> in a manner that an axial bearing surface between a front housing <NUM> and an orbiting scroll <NUM> to be described later can be effectively lubricated by oil while a point where the oil return pipe <NUM> is connected to a casing is spaced as far as possible from a point where the refrigerant suction pipe <NUM> is connected to the casing.

<FIG> is a schematic view illustrating a connection relation between a compressor and an oil return unit in <FIG>, <FIG> is an exploded perspective view illustrating a portion of the compressor in <FIG>, and <FIG> is an assembled cross-sectional view of <FIG>.

As illustrated in these drawings, the scroll compressor <NUM> according to the embodiment includes a casing <NUM>, a drive shaft <NUM>, an orbiting scroll <NUM> and a fixed scroll <NUM> constituting a compression part, a refrigerant return unit <NUM>, and an oil return unit <NUM>.

The casing <NUM> includes a main housing <NUM>, a front housing <NUM>, and a rear housing <NUM>.

The casing <NUM> defines appearance of the compressor <NUM>. The casing <NUM> is disposed on one side of the clutch assembly <NUM> and coupled to the clutch assembly <NUM> by the drive shaft <NUM>. Hereinafter, a side facing the clutch assembly <NUM> is defined as the front and an opposite side as the rear, and a description will be given based on the definition. Accordingly, the front housing <NUM> refers to a housing disposed on the side facing the clutch assembly <NUM>, and the rear housing <NUM> refers to a housing disposed on the opposite side.

The main housing <NUM> is formed in a cylindrical shape with both ends open so as to receive the compression part. In other words, an inner space of the main housing <NUM> forms a suction space 110a into which refrigerant passing through the evaporator <NUM> is suctioned. However, the suction space of the main housing <NUM> also defines an oil sump, in which not only refrigerant but also oil for lubricating a sliding part including the compression part are stored.

One end (front end) of the main housing <NUM> is covered with the front housing <NUM> coupled thereto, and another end (rear end) of the main housing <NUM> is covered with the rear housing <NUM> coupled thereto. Accordingly, the inner space of the main housing <NUM> is sealed by the front housing <NUM> and the rear housing <NUM>. However, since the drive shaft <NUM> is inserted through the front housing <NUM>, a shaft sealing member <NUM>, which will be described later, is disposed between the front housing <NUM> and the drive shaft <NUM>. Accordingly, the front end of the main housing <NUM> is sealed by the front housing <NUM> and the shaft sealing member <NUM>, but for convenience, hereinafter, a description will be given of an example in which one end of the main housing <NUM> is sealed by the front housing <NUM>.

The front housing <NUM> and the rear housing <NUM> may be coupled to the main housing <NUM> in a welding manner or by bolts. In this embodiment, an example in which the front housing <NUM> and the rear housing <NUM> are fastened to the main housing <NUM> by bolts will be mainly described.

A first housing protrusion 111a protrudes from one end of the main housing <NUM> into in a flange shape. The first housing protrusion 111a is fastened by bolts to a cover portion <NUM> of the front housing <NUM> to be described later. A first sealing member <NUM> such as an O-ring or a gasket may be inserted between the first housing protrusion 111a and the cover portion <NUM>.

A second housing protrusion 111b protrudes from a rear end of the main housing <NUM> into in a flange shape. The second housing protrusion 111b is fastened by bolts to a third housing protrusion 113a of the rear housing <NUM> to be described later. A second sealing member <NUM> such as an O-ring or a gasket may be inserted between the second housing protrusion 111b and the third housing protrusion 113a.

A first connection protrusion (no reference numeral given) is formed on an outer circumferential surface of the main housing <NUM>, that is, on an outer circumferential surface between the first housing protrusion 111a and the second housing protrusion 111b. A refrigerant suction port <NUM><NUM> is formed in the first connection protrusion to penetrate through between outer and inner surfaces of the main housing. An outer end of the refrigerant suction port <NUM> is connected to the refrigerant suction pipe <NUM>, and an inner end of the refrigerant suction port <NUM> is open to an inner circumferential surface of the main housing <NUM>. Accordingly, the refrigerant suction pipe <NUM> communicates with the inner space of the casing <NUM>, i.e., the suction space 110a through the refrigerant suction port <NUM>.

The refrigerant suction port <NUM> may be formed at a middle position of the main housing <NUM>, but may be located to be as close as possible to a first suction end 132a to be described later. For example, the first suction port <NUM> may be located to be closer to the second housing protrusion 111b than to the first housing protrusion 111a. Accordingly, the refrigerant suction port <NUM> is brought close to the first suction end 132a, which will be described later, so that suction resistance of refrigerant suctioned into the compression chamber V through the refrigerant suction port <NUM> can be reduced.

A second connection protrusion (no reference numeral given) is formed on an outer circumferential surface of the main housing <NUM>, that is, on an outer circumferential surface between the first housing protrusion 111a and the second housing protrusion 111b. A return port <NUM> is formed in the second connection protrusion to penetrate through between outer and inner surfaces of the main housing <NUM>. An outer end of the return port <NUM> is connected to the refrigerant suction pipe <NUM>, and an inner end of the return port <NUM> is open to an inner circumferential surface of the main housing <NUM>. Accordingly, the refrigerant suction pipe <NUM> (or oil return pipe) communicates with the inner space of the casing <NUM>, i.e., the suction space 110a through the return port <NUM>.

The return port <NUM> may be located to be close to the axial bearing surface between the front housing <NUM> and the orbiting scroll <NUM>. For example, the return port <NUM> may be formed at a position where it radially overlaps the axial bearing surface between the first housing protrusion 111a and the refrigerant suction port <NUM>. Accordingly, oil returned to the suction space 110a of the casing <NUM> through the return port <NUM> can be quickly fed to the axial bearing surface between the front housing <NUM> and the orbiting scroll <NUM>, so as to increase a lubricating effect between the front housing <NUM> and the orbiting scroll <NUM>.

The front housing <NUM> is coupled to the front end of the main housing <NUM> to seal the inner space of the main housing <NUM>, that is, the suction space 110a, and simultaneously support the orbiting scroll <NUM> in the axial direction. Accordingly, the front housing <NUM> may be understood as a portion of the casing <NUM> or as a frame constituting a portion of the compression part.

The front housing <NUM> may be formed of an aluminum material to reduce a weight of the compressor when applied to a vehicle. However, since a compressor applied for building air conditioning is fixed to an outdoor unit, the front housing <NUM> may be made of cast iron material instead of the aluminum material. This can increase reliability of the compressor for the building air conditioning, which has a higher load than the compressor for the vehicle.

Specifically, the front housing <NUM> according to the embodiment includes a cover portion <NUM> and a frame portion <NUM>. The cover portion <NUM> defines a portion of the casing <NUM> and the frame portion <NUM> defines a portion of the compression part.

The cover portion <NUM> and the frame portion <NUM> may be integrally formed with each other or may be separately manufactured to be assembled with each other. Although the embodiment illustrates an example in which the cover portion <NUM> and the frame portion <NUM> are integrally formed with each other, the present disclosure may be equally applied to a case where the cover portion <NUM> and the frame portion <NUM> are separately manufactured and assembled with each other later.

The cover portion <NUM> of the front housing <NUM> according to the embodiment is a portion that covers the front end of the main housing <NUM> from the outside of the main housing <NUM>, and is formed as a whole in the shape of an annular circular plate with a hollow center. An outer diameter of the cover portion <NUM> may be substantially the same as an outer diameter of the main housing <NUM>, more precisely, an outer diameter of the first housing protrusion 111a. Accordingly, the cover portion <NUM> is fastened by bolts to the first housing protrusion 111a of the main housing <NUM> to cover the front end of the main housing <NUM>.

A cover protrusion 1121a that extends toward the clutch assembly <NUM> on the same axis is formed on a front surface of the cover portion <NUM>. The cover protrusion 1121a is inserted and supported in the clutch assembly <NUM> with a clutch bearing (no reference numeral given) interposed therebetween. Accordingly, a drive part (no reference numeral given) of the clutch assembly <NUM> may be rotatably supported with respect to the cover protrusion 1121a.

A shaft receiving portion 1121b is formed through an inside of the cover portion <NUM>. The shaft receiving portion 1121b is formed on the same axis as an orbiting space 1122a of the frame portion <NUM> to be described later. Accordingly, the drive shaft <NUM> is inserted through the shaft receiving portion 1121b of the cover portion <NUM> and the orbiting space 1122a of the frame portion <NUM>, such that a front end of the drive shaft <NUM> is coupled to the clutch assembly <NUM> and a rear end to the orbiting scroll <NUM>, respectively.

The shaft receiving portion 1121b may be formed to be multiply stepped. For example, a front side of the shaft receiving portion 1121b may have a small inner diameter and a rear side thereof may have a large inner diameter. A front shaft receiving portion 1121b1 may be provided with a first support bearing <NUM> for supporting the front side of the drive shaft <NUM>, and a rear shaft receiving portion 1121b2 may be provided with a second support bearing <NUM> for supporting the rear side of the drive shaft <NUM>.

The first support bearing <NUM> and the second support bearing <NUM> may be configured as ball bearings. However, in some cases, the first support bearing <NUM> and the second support bearing <NUM> may be configured as needle bearings or bush bearings. However, as the orbiting scroll <NUM> constituting the compression part is coupled to the rear side of the drive shaft <NUM>, the second support bearing <NUM> is preferably configured as a bearing having a relatively large load bearing capacity compared to the first support bearing <NUM>.

In addition, a lubrication space 1121c may be defined in one side of the shaft receiving portion 1121b, that is, between the front shaft receiving portion 1121b1 and the rear shaft receiving portion 1121b2. An inner diameter of the lubrication space 1121c may be larger than an inner diameter of the front shaft receiving portion 1121b1 and smaller than an inner diameter of the rear shaft receiving portion 1121b2. Accordingly, the inner diameter may increase step by step from the front shaft receiving portion 1121b1 to the rear shaft receiving portion 1121b2 through the lubrication space 1121c.

A shaft sealing member <NUM> is disposed in the lubrication space 1121c. Specifically, the shaft sealing member <NUM> may be located between the first support bearing <NUM> and the second support bearing <NUM>, that is, between the lubrication space 1121c and the front shaft receiving portion 1121b1. Thus, a portion of the shaft sealing member <NUM> is located in the front shaft receiving portion 1121b1 and another portion in the lubrication space 1121c.

The shaft sealing member <NUM> may be usually configured as a mechanical seal. For example, the shaft sealing member <NUM> may include a fixed sealing portion <NUM> and a movable sealing portion <NUM>. The fixed sealing portion <NUM> may be coupled to an inner circumferential surface of the front shaft receiving portion 1121b1, and the movable sealing portion <NUM> may be coupled to an outer circumferential surface of the drive shaft <NUM>, respectively. Accordingly, when the drive shaft <NUM> rotates, the movable sealing portion <NUM> is brought into close contact with the fixed sealing portion <NUM> to seal a gap between the front shaft receiving portion 1121b1 and the lubrication space 1121c, that is, the front side of the suction space 110a.

The frame portion <NUM> of the front housing <NUM> is a portion inserted into the main housing <NUM> and extends integrally from the cover portion <NUM> toward the rear housing <NUM>. Accordingly, there is no need to fasten the cover portion <NUM> and the frame portion <NUM>, which can facilitate the formation of the front housing <NUM>. However, as described above, the frame portion <NUM> may be manufactured separately from the cover portion <NUM>, and then coupled to the cover portion <NUM> by bolts. In this case, the second support bearing <NUM> and the shaft sealing member <NUM> can be easily assembled.

An outer circumferential surface of the frame portion <NUM> may be coupled to an upper circumferential surface of the main housing substantially in a close contact manner. In other words, the front housing <NUM> may be shrink-fitted or welded to the casing <NUM>. However, in this embodiment, as the front housing <NUM> is fastened by bolts to the main housing <NUM>, the outer circumferential surface of the front housing <NUM> may be spaced apart from the inner circumferential surface of the main housing <NUM>. This can suppress heat or vibration of the front housing <NUM> from being transferred to the main housing <NUM>.

Although not illustrated, as the frame portion <NUM> is inserted into the main housing <NUM>, a first sealing member (not illustrated) may be disposed between an outer circumferential surface of the frame portion <NUM> and an inner circumferential surface of the main housing <NUM> facing the same.

The frame portion <NUM> is formed in an annular shape, and the orbiting space 1122a is defined in a central portion. The orbiting space 1122a is a space in which a drive shaft coupling portion <NUM> of the orbiting scroll <NUM> to be described later performs an orbiting motion, and is formed through the frame portion <NUM> to communicate with the shaft receiving portion 1121b and the lubricating space 1121c on the same axis.

A rear surface of the frame portion <NUM> defines a scroll support surface 1122b. In other words, the rear surface of the frame portion <NUM> facing the orbiting scroll <NUM> defines the scroll support surface 1122b on which an orbiting end plate <NUM> to be described later is supported in the axial direction. Accordingly, the scroll support surface 1122b defines the axial bearing surface described above together with a front surface of the orbiting end plate <NUM> facing the scroll support surface 1122b.

The scroll support surface 1122b may be formed to be flat as a whole, or at least one oil groove 1122c may be formed so that the scroll support surface 1122b is uneven. The oil groove may alternatively be formed in the front surface of the orbiting end plate <NUM> facing the scroll support surface 1122b. In this embodiment, an example in which the oil grooves 1122b are formed in the scroll support surface 1122b is illustrated.

For example, the oil grooves 1122c may include a first oil groove 1122c1 and a second oil groove 1122c2. The first oil groove 1122c1 is provided in plurality in a radial direction, and the second oil groove 1122c2 is provided by at least one in number to intersect the first oil grooves 1121c1 in the circumferential direction. In other words, the plurality of first oil grooves 1122c1 are disposed at predetermined distances along the circumferential direction, whereas the second oil groove 1122c2 may be formed across the first oil grooves 1122c1. Accordingly, the plurality of first oil grooves 1122c1 can communicate with one another by the second oil groove 1122c2.

Also, the first oil grooves 1122c1 may be disposed at an equal distance in the circumferential direction. In other words, the first oil grooves 1122c1 may be formed at the same oil groove distance α along the circumferential direction. This can facilitate the formation of the first oil grooves 1122c1 and simultaneously allow oil to be approximately equally supplied to the entire axial bearing surface.

In addition, the first oil groove 1122c1 may be formed in the same standard, that is, the same width and depth. In other words, the first oil grooves 1122c1 may have the same oil groove width β along the circumferential direction. This can facilitate the formation of the first oil grooves 1122c1 and simultaneously allow oil to be approximately equally supplied to the entire axial bearing surface.

The second oil groove 1122c2 may be one groove formed across middle portions of the first oil grooves 1122c1 or may include a plurality of circular grooves spaced apart in the radial direction. The second oil groove 1122c2 may have the same depth as the first oil groove 1122c1.

Although not illustrated, the first oil grooves 1122c1 and the second oil supply groove 1122c2 may be formed in various shapes. For example, the first oil groove 1122c1 may be formed in a tapered shape having a wide outer circumference and a narrow inner circumference, and the second oil groove 1122c2 may be formed in a linear shape.

Although not illustrated, the oil groove 1122c may not be configured as the first oil grooves 1122c1 and the second oil groove 1122c2. For example, the oil groove 1122c may include only the first oil grooves 1122c1 or only the second oil groove 1122c2.

Although not illustrated, the first oil grooves 1122c1 may be formed in different standards at different distances along the circumferential direction.

On the other hand, an anti-rotation pin <NUM> constituting an anti-rotation mechanism <NUM> together with a ring insertion groove (or anti-rotation ring) to be described later is disposed on the scroll support surface 1122b. The anti-rotation pin <NUM> is provided in plurality disposed at preset distances, for example, between the neighboring oil grooves 1122c to be described later, in the circumferential direction. Accordingly, the anti-rotation pins <NUM> suppress the rotation of the orbiting scroll <NUM> together with a ring insertion groove (or anti-rotation ring) <NUM> to be described later. The anti-rotation pin <NUM> will be described later together with the anti-rotation ring <NUM>.

At the same time, oil which is stored in the suction space 110a of the casing <NUM>, that is, in the oil storage space defining the lower half of the suction space 110a, can be supplied into a gap between the front housing <NUM> and the orbiting scroll <NUM> (to be precise, between the thrust plate <NUM> and the front housing <NUM> and between the thrust plate <NUM> and the orbiting scroll <NUM>, which will be described later) through the oil groove 1122c.

The anti-rotation pins <NUM> may extend integrally from the rear surface of the frame portion <NUM> toward the orbiting scroll <NUM> or may be separately manufactured and then assembled. In this embodiment, an example in which the anti-rotation pin is press-fitted to the frame portion <NUM> is illustrated.

The rear housing <NUM> according to the embodiment is formed in a substantially cylindrical shape with one end (front end) open and another end (rear end) closed. In other words, the front end of the rear housing <NUM> facing the fixed scroll <NUM>, which will be described later, is open while the rear end facing the fixed scroll <NUM> is closed. Accordingly, an inner space of the rear housing <NUM> defines a discharge space 110b together with a rear surface of a fixed end plate <NUM>, which will be described later, so as to accommodate refrigerant discharged from the compression chamber V.

The third housing protrusion 113a fastened by bolts to the second housing protrusion 111b extends from the front end of the rear housing <NUM> into a flange shape. The third housing protrusion 113a and the second housing protrusion 111b are fastened by bolts to each other with the second sealing member <NUM> interposed therebetween.

Although not illustrated, the second housing protrusion 111b and the rear housing <NUM> may be fastened by bolts to each other with a spacer (not illustrated) interposed therebetween. In this case, a sealing protrusion (not illustrated) may extend from the front end of the rear housing <NUM> toward the main housing <NUM>, and a second sealing member (not illustrated) may be disposed between an outer circumferential surface of the sealing protrusion and the inner circumferential surface of the main housing <NUM>.

A third connection protrusion (no reference numeral given) and a fourth connection protrusion (no reference numeral given) are formed on the closed rear end of the rear housing <NUM>. The third connection protrusion is formed on a center of the rear end of the rear housing <NUM>, and the fourth connection protrusion is formed near the third connection protrusion. A refrigerant discharge port <NUM> is formed in the third connection protrusion, and a bypass port <NUM> is formed in the fourth connection protrusion. The refrigerant discharge port <NUM> and the bypass port <NUM> are formed through between inner and outer surfaces of the rear housing <NUM>.

An inner end of the refrigerant discharge port <NUM> is open to an inner circumferential surface of the rear housing <NUM> to communicate with a discharge port <NUM> to be described later, and an outer end of the refrigerant discharge port <NUM> is connected to the refrigerant discharge pipe <NUM>. Accordingly, the refrigerant discharge pipe <NUM> communicates with the inner space of the rear housing <NUM>, that is, the discharge space 110b through the refrigerant discharge port <NUM>. The refrigerant discharge pipe <NUM> is connected to an inlet of the oil separator <NUM>, and an outlet of the oil separator <NUM> is connected the condenser <NUM> of the refrigeration cycle constituting the gas engine heat pump <NUM> through the refrigerant circulation pipe <NUM>.

An inner end of the bypass port <NUM> is open to the inner circumferential surface of the rear housing <NUM> to communicate with a bypass guide groove 1411c to be described later, and an outer end of the bypass port <NUM> is connected to the refrigerant return pipe <NUM>. Accordingly, the inner space of the rear housing <NUM>, that is, the bypass guide groove 1411c communicates with a first end 151a of the refrigerant return pipe <NUM> by the bypass port <NUM>. A second end 151b of the refrigerant return pipe <NUM> may be directly connected to the return port <NUM> of the main housing <NUM> or may be connected to the main housing <NUM> through the oil return pipe <NUM>. An example in which the second end 151b of the refrigerant return pipe <NUM> is directly connected to the return port <NUM> of the main housing <NUM> is illustrated.

The drive shaft <NUM> according to this embodiment transmits driving force, which is transmitted through the clutch assembly <NUM>, to the compression part, that is, the orbiting scroll <NUM>. A portion of the drive shaft <NUM> is disposed outside the casing <NUM> and another portion of the drive shaft <NUM> is disposed inside the casing <NUM>, respectively.

In detail, the drive shaft <NUM> includes a shaft portion <NUM> and a pin portion <NUM>. The shaft portion <NUM> is coupled to the clutch assembly <NUM>, and the pin portion <NUM> extends from the shaft portion <NUM> to be coupled to the orbiting scroll <NUM> with interposing an eccentric bush <NUM> to be described later therebetween. Accordingly, the driving force transmitted through the clutch assembly <NUM> is transmitted to the orbiting scroll <NUM> through the drive shaft <NUM>.

The shaft portion <NUM> is disposed on the same axis as the shaft receiving portion 1121b and the lubrication space 1121c of the front housing <NUM>. A front end of the shaft portion <NUM> is supported by the first support bearing <NUM> disposed in the front shaft receiving portion 1121b1 of the front housing <NUM>, and a rear end of the shaft portion <NUM> is supported by the second support bearing <NUM> disposed in the rear shaft receiving portion 1121b2. The shaft portion <NUM> rotates while being radially supported at two points by the first support bearing <NUM> and the second support bearing <NUM> which are spaced apart from each other in the axial direction.

An oil passage (not illustrated) may be defined through the inside of the shaft portion <NUM>. As the front end of the shaft portion <NUM> is exposed to the outside of the casing <NUM>, the oil passage may be formed toward the lubrication space 1121c through an outer circumferential surface of the shaft portion <NUM> in a middle of the shaft portion <NUM>.

The pin portion <NUM> extends axially from the rear end of the shaft portion <NUM> toward the orbiting scroll <NUM>. The pin portion <NUM> is formed eccentrically with respect to an axial center O of the shaft portion <NUM>, and the eccentric bush (or sliding bush) <NUM> is rotatably coupled to the pin portion <NUM>. Accordingly, rotational force of the drive shaft <NUM> is transmitted to the orbiting scroll <NUM> with the eccentric bush <NUM> interposed therebetween, and the orbiting scroll <NUM> performs an orbiting motion by the anti-rotation mechanism <NUM>.

A sub-balance weight <NUM> that performs an orbiting motion in the shaft receiving portion 1121b of the front housing <NUM> may be formed integrally with the eccentric bush <NUM> or may be press-fitted into the eccentric bush <NUM>. The sub-balance weight <NUM> is formed in a semicircular shape on the same axis as the axial center O of the drive shaft <NUM>, and is disposed at an opposite side to a direction in which the eccentric bush <NUM> is eccentric. Accordingly, the sub-balance weight <NUM> rotates in the orbiting space 1122a of the front housing <NUM>.

The orbiting scroll <NUM> is coupled to a rear end of the drive shaft <NUM> with the eccentric bush <NUM> interposed therebetween and is axially supported by the frame portion <NUM> of the front housing <NUM>. Accordingly, the orbiting scroll <NUM> performs the orbiting motion by receiving rotational force through the drive shaft <NUM> while being supported in the axial direction by the frame portion <NUM> of the front housing <NUM>.

In detail, the orbiting scroll <NUM> includes an orbiting end plate <NUM>, an orbiting wrap <NUM>, and a drive shaft coupling portion <NUM>. The orbiting scroll <NUM> may be formed of a material lighter than that of the front housing <NUM>, for example, an aluminum material. This can enhance efficiency of the compressor by reducing a load of a balance weight.

The orbiting end plate <NUM> is formed in a disk shape. The orbiting end plate <NUM> is provided with an orbiting wrap <NUM> formed on one side surface (rear surface) thereof and engaged with the fixed wrap <NUM> to be explained later so as to form the compression chamber V, and a driving shaft coupling portion <NUM> formed on another side surface (front surface) and coupled to the eccentric bush <NUM> to receive rotational force through the drive shaft <NUM>. Accordingly, the rear surface of the orbiting end plate <NUM> forms the compression chamber V together with the front surface of the fixed end plate <NUM> to be described later, while the front surface of the orbiting end plate <NUM> is axially supported by the scroll support surface 1122b of the front housing <NUM> so as to define an axial bearing surface.

A thrust plate <NUM> may be provided between the rear surface of the orbiting end plate <NUM> and the scroll support surface 1122b. However, when the front housing <NUM> and the orbiting scroll <NUM> defining the axial bearing surface are made of different materials, the thrust plate <NUM> may be excluded. However, in the embodiment, an example in which the front housing <NUM> and the orbiting scroll <NUM> are made of different materials but the thrust plate <NUM> is interposed between the front housing <NUM> and the orbiting scroll <NUM> will be mainly described.

The thrust plate <NUM> may be formed of a material different from that of the orbiting scroll <NUM> or/and the front housing <NUM>. For example, the front housing <NUM> may be formed of cast iron and the orbiting scroll <NUM> may be made of aluminum. The thrust plate <NUM> may be formed of a steel plate having greater rigidity than the material(s) of the front housing <NUM> or/and the orbiting scroll <NUM>. This can allow more effective lubrication between the orbiting scroll <NUM> and the front housing <NUM>.

The thrust plate <NUM> is formed in an annular shape. For example, the thrust plate <NUM> is formed substantially in the same shape as that of the scroll support surface 1122b of the front housing <NUM>. Pin holes <NUM> are formed in the thrust plate <NUM> so that the anti-rotation pins <NUM> are inserted. The pin holes <NUM> are disposed at preset distances in the circumferential direction to correspond to the anti-rotation pins <NUM>. Accordingly, the thrust plate <NUM> can be coupled to the scroll support surface 1122b of the front housing <NUM> by the anti-rotation pins <NUM>.

A ring insertion groove <NUM> is formed in the front surface of the orbiting end plate <NUM> so that the anti-rotation pin <NUM> constituting a portion of the anti-rotation mechanism <NUM> is pivotally inserted. Accordingly, the orbiting scroll <NUM> receiving the rotational force by the drive shaft <NUM> performs the orbiting motion by the anti-rotation ring <NUM> inserted into the ring insertion groove <NUM> and the ant-rotation pin <NUM> inserted into the ring insertion groove <NUM>.

The ring insertion groove <NUM> is provided in plurality disposed at preset distances in the circumferential direction. The ring insertion groove <NUM> may be formed in a closed circular shape, or in some cases, may be formed in an open arcuate shape. The embodiment exemplarily illustrates that the ring insertion groove <NUM> is formed in a circular shape.

The anti-rotation ring <NUM> constituting the portion of the anti-rotation mechanism <NUM> is rotatably inserted into the ring insertion groove <NUM>, and the anti-rotation pin <NUM> slides into the anti-rotation ring <NUM> in the circumferential direction. The anti-rotation ring <NUM> will be described later together with the anti-rotation pin <NUM>.

The orbiting wrap <NUM> extends toward the fixed scroll <NUM> from one side surface (rear surface) of the orbiting end plate <NUM>. The orbiting wrap <NUM> may be formed in various shapes, such as an involute shape, to correspond to the fixed wrap <NUM>.

A tip seal groove may be formed in an axial end surface of the orbiting wrap <NUM>, so that a tip seal member (no reference numeral given) can be inserted therein. This can suppress axial leakage between compression chambers through the axial end surface of the orbiting wrap <NUM>.

The orbiting wrap <NUM> may extend up to an outer circumferential surface of the orbiting end plate <NUM>. Accordingly, a wrap length of the orbiting wrap <NUM> can extend to the maximum, thereby maximizing a suction volume.

A first suction end 132a and a second suction end 142a which communicate independently with both compression chambers V1 and V2 may be formed on an end of the orbiting wrap <NUM> in a wrapping (rolling, winding) direction and an end of the fixed wrap <NUM> in a wrapping (rolling, winding) direction to be described later. This will be described later again together with the fixed wrap <NUM>.

The drive shaft coupling portion <NUM> extends toward the front housing <NUM> from a geometric center of the orbiting scroll <NUM>. The drive shaft coupling portion <NUM> is formed in a cylindrical shape, and a third support bearing <NUM> may be disposed between an inner circumferential surface of the drive shaft coupling portion <NUM> and an outer circumferential surface of the eccentric bush <NUM>. The third support bearing <NUM> may be a bush bearing, a ball bearing, or a needle bearing. This embodiment illustrates an example in which the needle bearing is employed.

In the state where the fixed scroll <NUM> is inserted into the main housing <NUM>, a front surface of the fixed scroll <NUM> is supported by being fixed to the front housing <NUM> and a rear surface thereof is supported by being fixed to the rear housing <NUM> in the axial direction. Accordingly, the inner space of the casing <NUM> is divided based on the fixed scroll <NUM> into a suction space 110a for accommodating the orbiting scroll <NUM> and a discharge space 110b including a portion of the fixed scroll <NUM>, and the pair of compression chambers are formed while the orbiting scroll <NUM> perform the orbiting motion related to the fixed scroll <NUM>.

In detail, the fixed scroll <NUM> includes a fixed end plate <NUM> and a fixed wrap <NUM>.

The fixed end plate <NUM> is formed in a disk shape. An outer circumferential surface of the fixed end plate <NUM> may be inserted to be almost brought into contact with the inner circumferential surface of the casing <NUM>, that is, the inner circumferential surface of the main housing <NUM>. A third sealing member <NUM> may be inserted into an outer circumferential surface of the fixed end plate <NUM>. This can tightly seal a gap between the outer circumferential surface of the fixed end plate <NUM> and the inner circumferential surface of the main housing <NUM>, so that the inner space of the casing can be divided into the suction space 110a (and oil storage space) at the front side and the discharge space 110b at the rear side.

Although not illustrated, when the aforementioned sealing protrusion (not illustrated) is formed on the rear housing <NUM>, the third sealing member (not illustrated) may be inserted between the inner circumferential surface of the sealing protrusion and the outer circumferential surface of the fixed end plate <NUM> facing it.

The discharge port <NUM> is formed in a center of the fixed end plate <NUM>. The discharge port <NUM> may be a single portion formed to communicate with both compression chambers V, or may be provided in plurality disposed to communicate with both compression chambers V independently of each other. In this embodiment, an example in which one discharge port <NUM> is formed is illustrated.

At least one bypass hole 1412a, 1412b may be formed in the vicinity of the discharge port <NUM>. The at least one bypass hole 1412a, 1412b may include an overcompression-suppressing bypass hole (hereinafter, referred to as a first bypass hole) 1412a for suppressing overcompression and/or a variable capacity bypass hole (hereinafter, referred to as a second bypass hole) 1412b for varying capacity. The first bypass hole 1412a may be independently formed for each compression chamber V in the vicinity of the discharge port <NUM>, and the second bypass hole 1412b may be independently formed for each compression chamber at a position farther away from the discharge port <NUM> than the first bypass hole 1412a.

The discharge port <NUM>, the first bypass hole 1412a, and the second bypass hole 1412b are open and closed by valves, respectively. For example, the discharge port <NUM> is open and closed by a discharge valve <NUM>, the first bypass hole 1412a by a first bypass valve <NUM>, and the second bypass hole 1412b by a second bypass valve <NUM>.

The discharge valve <NUM>, the first bypass valve <NUM>, and the second bypass valve <NUM> may be configured independently, or may be integrally connected to each other. This embodiment illustrates an example in which the discharge valve <NUM> and the first bypass valve <NUM> are independently disposed, whereas the second bypass valve <NUM> is provided by two integrally connected to each other.

On the other hand, the discharge space 110b is defined between the rear surface of the fixed end plate <NUM> and the inner space of the rear housing <NUM> facing it. Here, the discharge space 110b may be divided into a first discharge space 110b1 and a second discharge space 110b. For example, a partition protrusion <NUM> may extend from the rear surface of the fixed end plate <NUM> toward the rear housing <NUM> by a preset height.

The partition protrusion <NUM> may be formed in a ring shape similar to an alphabet V when projected in the axial direction, so as to partition the discharge space 110b into the first discharge space 110b1 and the second discharge space 110b2. For example, the first discharge space 110b1 may be formed outside the partition protrusion <NUM>, and the second discharge space 110b2 may be formed inside the partition protrusion <NUM>, respectively.

The first discharge space 110b1 may communicate with the refrigerant discharge port <NUM> described above, and the second discharge space 110b2 may communicate with the bypass port <NUM> described above. The discharge valve <NUM> and the first bypass valve <NUM> belong to the first discharge space 110b1, and the second bypass valve <NUM> belongs to the second discharge space 110b2. Accordingly, the first discharge space 110b1 defines a substantial discharge space for guiding refrigerants, which are discharged from discharge pressure chambers (no reference numeral given) of the both compression chambers V or bypassed from first intermediate pressure chambers (no reference numeral given) of the both compression chambers V, toward the condenser <NUM> of the refrigeration cycle through the refrigerant discharge pipe <NUM> to be described later. And, the second discharge space 110b2 defines a kind of bypass space for guiding refrigerants, which are bypassed from intermediate compression chambers (second intermediate pressure chambers with pressure lower than the first intermediate pressure chambers) of the both compression chambers, to be returned into the suction space 110a of the casing <NUM> through the refrigerant return pipe <NUM> to be described later.

The partition protrusion <NUM> may be formed only on the fixed end plate <NUM>, but in some cases, may also be formed on the front surface of the rear housing <NUM> facing the fixed end plate <NUM>. For example, a first partition protrusion <NUM> (also, denoted by the same reference numeral of the partition protrusion for the sake of explanation) may be formed on the rear surface of the fixed end plate <NUM>, and a second partition protrusion <NUM> corresponding to the first partition protrusion may be formed on the front surface of the rear housing <NUM>. In this case, the refrigerant discharge port <NUM> may be located outside the second partition protrusion <NUM> and a bypass port <NUM> may be located inside the second partition protrusion <NUM>, respectively.

A bypass guide groove 1413a is formed inside the partition protrusion <NUM>. The bypass guide groove 1413a is formed in a substantially V-like shape to accommodate the second bypass holes 1412b of the both compression chambers V. When the partition protrusion is divided into the first partition protrusion <NUM> and the second partition protrusion <NUM>, the bypass guide groove may be formed in each of the first partition protrusion <NUM> and the second partition protrusion <NUM>, or in any one of the partition protrusions.

The fixed wrap <NUM> extends toward the orbiting scroll <NUM> from one side surface (front surface) of the fixed end plate <NUM>. The fixed wrap <NUM> and the orbiting wrap <NUM> may be formed in various shapes, such as an involute shape, to correspond to the orbiting wrap <NUM>.

A tip seal groove may be formed in an axial end surface of the fixed wrap <NUM>, so that a tip seal member (no reference numeral given) can be inserted therein. This can suppress axial leakage between compression chambers through the axial end surface of the fixed wrap <NUM>.

The fixed wrap <NUM> may extend up to the outer circumferential surface of the fixed end plate <NUM>, like the orbital wrap <NUM>. Accordingly, a wrap length of the fixed wrap <NUM> can extend to the maximum, thereby maximizing a suction volume.

The fixed wrap <NUM> is disposed such that an end thereof in a wrapping direction has a phase difference of about <NUM>° from an end of the orbiting wrap <NUM> in a wrapping direction thereof. For example, a first suction end 132a to be described later is formed on an outer end of the orbiting wrap <NUM>, and a second suction end 142a is formed on an outer end of the fixed wrap <NUM>, respectively. Accordingly, the fixed wrap <NUM> forms so-called symmetrical compression chambers together with the orbital wrap <NUM>.

Referring to <FIG>, a refrigerant return unit <NUM> according to the embodiment includes a refrigerant return pipe <NUM> and a first control valve <NUM>.

As described above, the refrigerant return pipe <NUM> is configured such that a first end 151a is fastened to the third connection protrusion (no reference numeral given) of the rear housing <NUM> to be connected to the bypass port <NUM> communicating with the second discharge space 110b2, and a second end is fastened to the second connection protrusion of the main housing <NUM> to be connected to the return port <NUM> communicating with the suction space 110a. Accordingly, refrigerants bypassed from both compression chambers V forming the second intermediate pressure chambers to the bypass guide groove 1413a are suctioned again after circulating the suction space 110a of the casing <NUM> through the refrigerant return pipe <NUM>.

The first control valve <NUM> is disposed in a middle portion of the refrigerant return pipe <NUM> to open and close the refrigerant return pipe <NUM>. The first control valve <NUM> may be a check valve or a solenoid valve that is open and closed by receiving an electrical signal transmitted from a controller (not illustrated) of the gas engine heat pump <NUM>. In this embodiment, an example in which the first control valve <NUM> is a solenoid valve is illustrated. Accordingly, the first control valve <NUM> is open when it is necessary to lower the capacity of the compressor, such that refrigerant bypassed by the bypass guide groove 1413a circulates to the suction space 110a of the casing <NUM>, thereby switching the compressor into a saving operation mode.

An oil return unit <NUM> according to the embodiment includes an oil separator <NUM>, an oil return pipe <NUM>, and a second control valve <NUM>.

Referring to <FIG>, the refrigerant discharge pipe <NUM> is connected to an upper half of the oil separator <NUM>, and the refrigerant circulation pipe <NUM> which is connected to the inlet of the condenser is connected to an upper end (or upper surface) of the oil separator <NUM>. In addition, the oil return pipe <NUM> which is joined to the refrigerant return pipe <NUM> toward the suction space of the casing <NUM> is connected to a lower end (or lower half) of the oil separator <NUM>. Accordingly, refrigerant and oil discharged to the first discharge space 110b1 of the casing <NUM> are introduced into the oil separation space 161a of the oil separator <NUM> through the refrigerant discharge pipe <NUM>, and separated from each other in the oil separation space 161a by a kind of cyclonic effect. Gas refrigerant separated in an oil separation space 161a moves to the condenser <NUM> through the refrigerant circulation pipe <NUM>, while liquid oil separated in the oil separation space 161a is accumulated in the lower portion of the oil separation space 161a so as to be returned into the suction space 110a of the casing <NUM> via the oil return pipe <NUM> and the refrigerant return pipe <NUM>.

As described above, the oil return pipe <NUM> is configured such that a first end 162a is connected to the oil separator <NUM> disposed in the refrigerant discharge pipe <NUM> at the outside of the casing <NUM>, and a second end 162b is connected to a middle portion of the refrigerant return pipe <NUM>. In other words, the first end 162a of the oil return pipe <NUM> is connected to a second outlet side located in the lower half of the oil separator <NUM>, and the second end 162b of the oil return pipe <NUM> may be connected to the refrigerant return pipe <NUM> at a downstream side rather than the first control valve <NUM>. Accordingly, the oil separated in the oil separator <NUM> moves through the oil return pipe <NUM>, and flows into the refrigerant return pipe <NUM> to be returned into the suction space 110a of the casing <NUM> through the return port <NUM>.

The second control valve <NUM> is disposed in a middle portion of the oil return pipe <NUM> to open and close the oil return pipe <NUM>. The second control valve <NUM> may be a check valve or a solenoid valve that is open and closed by receiving an electrical signal transmitted from a controller (not illustrated) of the gas engine heat pump <NUM>. In this embodiment, an example in which the second control valve <NUM> is a solenoid valve is illustrated. Accordingly, when the compressor requires oil, the second control valve <NUM> is open such that the oil separated in the oil separator <NUM> is returned into the suction space 110a of the casing <NUM>, thereby reducing friction loss in the compressor and improving reliability.

Although not illustrated, the second control valve <NUM> may be excluded or may be configured as a check valve for preventing reverse flow. In this case, the oil separated in the oil separator <NUM> may be continuously returned to the suction space.

Although not illustrated, the second end 162b of the oil return pipe <NUM> may be fastened to the second connection protrusion to be directly connected to the return port <NUM>, and the second end 151b of the refrigerant return pipe <NUM> may be connected to the middle of the oil return pipe <NUM>. Even in this case, the second end 151b of the refrigerant return pipe <NUM> may be connected to the oil return pipe <NUM> at the downstream side rather than the second control valve <NUM>.

In the drawings, an unexplained reference numeral <NUM> denotes a main balance weight.

The scroll compressor according to the embodiment may operate as follows.

That is, when an operation for the gas engine heat pump <NUM> is selected, the clutch assembly <NUM> transmits driving force to the drive shaft <NUM>. The driving force transmitted to the drive shaft <NUM> is transmitted to the orbiting scroll <NUM> through the drive shaft <NUM>.

Then, in the state in which the orbiting scroll <NUM> is supported by the front housing <NUM>, the orbiting scroll <NUM> performs an orbiting motion by an eccentric distance of the eccentric bush <NUM>. During the orbiting motion, a pair of compression chambers V each including a suction chamber, an intermediate pressure chamber, and a discharge chamber are continuously formed between the orbiting wrap <NUM> and the fixed wrap <NUM>. The compression chambers V are decreased in volume as moving toward the center during the continuous orbiting motion of the orbiting scroll <NUM>, and refrigerant is compressed while moving along the compression chambers V and then discharged into the discharge space 110b, more accurately, the first discharge space 110b1 through the discharge port <NUM>.

At this time, the refrigerant in each compression chamber V may be compressed up to a set pressure while moving from the intermediate pressure chamber to the discharge pressure chamber, but the pressure of the refrigerant may rise over the preset pressure due to other conditions occurred during the operation of the compressor. Then, the refrigerant moving from the intermediate pressure chamber to the discharge pressure chamber is partially bypassed in advance from each compression chamber V to the discharge space 110b, more precisely, the first discharge space 110b1 through the first bypass hole 1412a. This can suppress overcompression of the refrigerant above the set pressure in each compression chamber V, so as to increase efficiency of the compressor and to secure stability for the orbital wrap <NUM> and the fixed wrap <NUM> constituting the compression part.

In addition, the gas engine heat pump <NUM> including the compressor <NUM> may vary an operating capacity as needed during operation. For example, in the case of a power operation, the first control valve <NUM> of the refrigerant return unit <NUM> is closed to secure a maximum suction volume, whereas in the case of a saving operation, the first control valve <NUM> of the refrigerant return unit <NUM> is open so as to substantially minimize the suction volume.

In other words, during the saving operation, as the first control valve <NUM> is open, the second discharge space 110b2 communicates with the suction space 110a. Then, the refrigerant suctioned into the compression chambers V are partially bypassed to the second discharge space through the second bypass hole 1412b. This refrigerant flows into the suction space 110a through the refrigerant return pipe <NUM> and the return port <NUM> by a pressure difference between the second discharge space 110b2 and the suction space 110a, and then suctioned into each of the both compression chambers V1 and V2 through the first suction end 132a and the second suction end 142a.

On the other hand, the refrigerant discharged to the first discharge space 110b1 through the discharge port <NUM> and the first bypass hole 1412a flows toward the condenser <NUM> of the refrigeration cycle device through the refrigerant discharge port <NUM> and the refrigerant discharge pipe <NUM>. However, oil is contained in the refrigerant discharged from each compression chamber V to the first discharge space 110b1.

As described above, when refrigerant and oil are both discharged from the compressor <NUM> toward the refrigeration cycle device, an oil shortage may occur in the casing <NUM> constituting the compressor <NUM>. In particular, the scroll compressor <NUM> included in the gas engine heat pump <NUM> does not store a large amount of oil due to a small internal volume of the casing <NUM>. Accordingly, the oil separator <NUM> is disposed between the scroll compressor <NUM> and the condenser <NUM> included in the gas engine heat pump <NUM>, to separate oil discharged from the compressor <NUM> from refrigerant, such that the oil is returned to the compressor <NUM>.

The oil separator <NUM> may be disposed inside the compressor <NUM> or outside the compressor <NUM>. As in the embodiment, when the oil separator <NUM> is disposed outside the compressor <NUM>, that is, in the middle of the refrigerant discharge pipe <NUM>, the oil return pipe <NUM> through which the oil separated in the oil separator <NUM> is returned into the casing <NUM> of the compressor <NUM> is provided. However, when the oil return pipe <NUM> is provided, the shape of the compressor for connecting the oil return pipe <NUM> or the piping around the compressor may be complicated.

Accordingly, in the embodiment, the oil return pipe may be joined to the refrigerant return pipe and connected to the casing of the compressor. Accordingly, the piping around the compressor can be simplified by unifying the refrigerant return pipe and the oil return pipe.

In addition, in this embodiment, the refrigerant return pipe connected to the oil separation pipe or the refrigerant return pipe may be disposed close to the axial bearing surface between the front housing and the orbiting scroll. Accordingly, oil can be quickly supplied between the front housing and the orbiting scroll, thereby reducing friction loss between the front housing and the orbiting scroll, which may result in improving efficiency of the compressor.

In addition, in the embodiment, an oil groove may be formed in the scroll support surface of the front housing or the front surface of the orbiting end plate facing the scroll support surface. Accordingly, even if the front housing and the orbiting scroll (or thrust plate) are in close contact with each other, oil can be quickly introduced into a gap between the front housing and the orbiting scroll through the oil groove, thereby further reducing friction loss.

Meanwhile, as described above, in the scroll compressor according to the embodiment, the anti-rotation pin is inserted into the front housing and the anti-rotation ring is inserted into the orbiting scroll, respectively, to suppress the rotation of the orbiting scroll.

However, as the related art anti-rotation ring is completely embedded in the ring insertion groove of the orbiting scroll, the front surface of the orbiting end plate and the rear surface of the thrust plate come into close contact with each other. As a result, sufficient oil is not supplied to the axial bearing surface between the orbiting scroll and the thrust plate. This may cause wear due to an increase in friction loss or an occurrence of seizure on the axial bearing surface. Even when the thrust plate is excluded, a similar phenomenon may occur between the front housing and the orbiting scroll.

Accordingly, in the embodiment of the present disclosure, a spacer may be disposed between the front housing and the orbiting scroll, specifically, between the thrust plate and the orbiting scroll. However, the spacer may be configured using an existing part, namely, the anti-rotation ring, without adding a separate part. Through this, oil can be quickly and sufficiently supplied to the axial bearing surface between the thrust plate and the orbiting scroll, thereby suppressing friction loss or seizure on the axial bearing surface.

<FIG> is an exploded perspective view illustrating a compression part in a scroll compressor in accordance with an embodiment of the present disclosure, <FIG> is a perspective view illustrating a rear surface of an orbiting scroll, to which an anti-rotation ring is coupled, in <FIG>, <FIG> is a rear view of <FIG>, and <FIG> is a cross-sectional view of <FIG>.

Referring to <FIG>, the anti-rotation mechanism <NUM> according to the embodiment may include an anti-rotation pin <NUM> and an anti-rotation ring <NUM>. These anti-rotation pin <NUM> and anti-rotation ring <NUM> form a pair, and a plurality of pairs are arranged at an equal distance one by one along the circumferential direction.

Specifically, the anti-rotation pin <NUM> is formed in a small circular rod shape, and may be formed of a material having hardness and strength higher than those of the orbiting scroll <NUM> and the front housing <NUM>. In other words, the anti-rotation pin <NUM> is formed in a small circular rod shape which has an inner diameter smaller than that of a pin coupling portion <NUM> of the anti-rotation ring <NUM> to be described later, and may be made of a material, such as steel, which has hardness and strength higher than those of the orbiting scroll <NUM> made of aluminum or the front housing <NUM> made of cast iron. Accordingly, the anti-rotation pin <NUM> cannot be damaged and can maintain reliability even if the anti-rotation pin <NUM> is coupled to the anti-rotation ring <NUM> to suppress the rotation of the orbiting scroll <NUM>.

The anti-rotation pins <NUM> are disposed at an equal distance along the circumferential direction on the rear surface of the front housing <NUM>, that is, the scroll support surface 1122b. The anti-rotation pins <NUM> can be rotatably coupled to the pin insertion grooves 1122d formed in the scroll support surface 1122b, or may be firmly press-fitted into the pin insertion grooves 1122d. In this embodiment, an example in which the anti-rotation pins <NUM> are press-fitted into the pin insertion grooves 1122d is illustrated. This can prevent the anti-rotation pins <NUM> from being separated from the front housing <NUM> when assembling the compressor, which can be advantageous in terms of assembling property.

An end portion of each anti-rotation pin <NUM>, that is, an end portion to be inserted into the anti-rotation ring <NUM> may be chamfered to be tapered or curved. This can facilitate the anti-rotation pin <NUM> to be inserted into a pin coupling portion <NUM> of the anti-rotation ring <NUM> to be described later.

The anti-rotation ring <NUM> according to this embodiment may include a ring body portion <NUM> and a pin coupling portion <NUM>. The ring body portion <NUM> is inserted into the ring insertion groove <NUM> to support the orbiting scroll <NUM> in the axial direction with respect to the thrust plate <NUM> disposed at an opposite side, and the anti-rotation pin <NUM> is rotatably inserted into the pin coupling portion <NUM> to support the anti-rotation pin <NUM> in a rotational direction. Accordingly, the anti-rotation ring <NUM> slides in the ring insertion groove <NUM> in the circumferential direction and performs an orbiting motion centering on the anti-rotation pin <NUM> to constrain the rotation of the orbiting scroll <NUM>.

Specifically, the ring body portion <NUM> according to this embodiment may be formed of the same material as the anti-rotation pin <NUM>. For example, the ring body portion <NUM> may be formed of a steel material. This can minimize wear of the ring body portion <NUM> of the anti-rotation ring <NUM> due to the anti-rotation pin <NUM> even if the anti-rotation pin <NUM> slides in the pin coupling portion <NUM> in the circumferential direction.

The ring body portion <NUM> may be formed in a disk shape. For example, the ring body portion <NUM> may be formed in a disk shape having a substantially same axial thickness as a whole. However, in some cases, the ring body portion <NUM> may be formed to be partially thick or thin. This embodiment will be mainly described based on an example in which the entire ring body portion <NUM> has the same axial thickness.

The ring body portion <NUM> is formed in a disk shape in a manner that an outer diameter of the ring body portion <NUM> is slightly smaller than an inner diameter of the ring insertion groove <NUM>. Accordingly, the anti-rotation ring <NUM> can be slidably coupled to the ring insertion groove <NUM> in the circumferential direction.

An axial thickness H1 of the ring body portion <NUM> may be larger than an axial depth H2 of the ring insertion groove <NUM>. Accordingly, a portion of the ring body portion <NUM> protrudes out of the ring insertion groove <NUM> to come into contact with the thrust plate <NUM>. Then, a spacing ΔH is generated between the orbiting scroll <NUM> and the thrust plate <NUM> by a height of the portion of the ring body portion <NUM> protruding to the outside of the ring insertion groove <NUM>. Oil is then introduced into a gap defined by the spacing ΔH so as to lubricate between the orbiting scroll <NUM> and the thrust plate <NUM>.

However, when the axial thickness H1 of the ring body portion <NUM> is too thick, it excessively protrudes from the ring insertion groove <NUM>. This may reduce supporting force for the orbiting scroll <NUM>, which may make a behavior of the orbiting scroll <NUM> unstable. As a result, compression loss may occur due to leakage between the compression chambers. Therefore, the axial thickness H1 of the ring body portion <NUM> may be preferably formed to be equal to or smaller than twice the axial depth H2 of the ring insertion groove <NUM>.

The pin coupling portion <NUM> may be formed to be eccentric from a center Oc of the ring body portion <NUM>. In other words, the pin coupling portion <NUM> is formed inside the ring body portion <NUM>, specifically, formed axially through the ring body portion <NUM> at a position eccentric from the center of the ring body portion <NUM> by a preset distance. Alternatively, the pin coupling portion <NUM> may be recessed by a predetermined depth from one side surface of the ring body portion <NUM> facing the thrust plate <NUM> to an opposite side.

The pin coupling portion <NUM> is to be rotatably coupled to the anti-rotation pin <NUM> as described above, and thus an inner diameter of the pin coupling portion <NUM> may be slightly larger than an outer diameter of the anti-rotation pin <NUM>. Accordingly, when the ring body portion <NUM> turns in the ring insertion groove <NUM>, the anti-rotation pin <NUM> slides in the pin coupling portion <NUM> in the circumferential direction, which can constrain the rotation of the orbiting scroll <NUM>.

When the anti-rotation mechanism according to the embodiment is disposed between the front housing <NUM> and the orbiting scroll <NUM>, that is, between the thrust plate <NUM> and the orbiting scroll <NUM>, the orbiting scroll <NUM> is spaced apart from the thrust plate <NUM> in the axial direction.

That is, the axial thickness H1 of the anti-rotation ring <NUM> according to the embodiment is formed to be larger than the axial depth H2 of the ring insertion groove <NUM> into which the anti-rotation ring <NUM> is inserted. Accordingly, even if the anti-rotation ring <NUM> is inserted into the ring insertion groove <NUM>, the anti-rotation ring <NUM> is partially exposed outside the ring insertion groove <NUM>.

Then, the anti-rotation ring <NUM> forms a kind of thrust bearing surface. Accordingly, the rear surface of the thrust plate <NUM> is lifted by a protruded height of the anti-rotation ring <NUM> without coming into contact with the front surface of the orbiting end plate <NUM>. Then, oil is introduced into a gap between the lifted rear surface of the thrust plate <NUM> and the front surface of the orbiting end plate <NUM>, thereby forming an oil film. This can suppress an occurrence of friction loss or/and seizure between the rear surface of the thrust plate <NUM> and the front surface of the orbiting end plate <NUM> during the operation of the compressor.

Hereinafter, a description will be given of another embodiment of an anti-rotation mechanism.

That is, in the foregoing implementation, the ring body portion of the anti-rotation ring is formed in the disk shape, but in some cases, the ring body portion may further include a weight-reducing portion.

<FIG> is a cut perspective view illustrating another embodiment of an anti-rotation ring, <FIG> is a planar view of <FIG>, <FIG> is a cross-sectional view of <FIG>, and <FIG> is a planar view illustrating still another embodiment of an anti-rotation ring.

Referring to <FIG>, the basic configuration of the anti-rotation pin <NUM> and the anti-rotation ring <NUM> constituting the anti-rotation mechanism <NUM> of the scroll compressor according to this embodiment and the effects thereof are the same as those of the previous embodiment. Therefore, a detailed description thereof will be replaced with the description for the previous embodiment.

However, in this embodiment, a weight-reducing portion <NUM> may further be disposed in the anti-rotation ring <NUM>. This can reduce a weight of the anti-rotation ring <NUM> and thus reduce a weight of a rotating body including the anti-rotation ring <NUM>, thereby enhancing efficiencies of the compressor and the gas engine heat pump including the same.

For example, as illustrated in <FIG> and <FIG>, the anti-rotation ring <NUM> includes a ring body portion <NUM> and a pin coupling portion <NUM>, and further include a weight-reducing portion <NUM> having a preset area in the ring body portion <NUM>.

The weight-reducing portion <NUM> may be eccentrically formed at a position that does not overlap the pin coupling portion <NUM>. In other words, since the pin coupling portion <NUM> is formed eccentrically to one side from a center Or of the ring body portion <NUM>, the weight-reducing portion <NUM> may be formed eccentrically to an opposite side of the pin coupling portion <NUM> from the center Or of the ring body portion <NUM>.

Specifically, the weight-reducing portion <NUM> according to this embodiment may be formed through both axial side surfaces of the ring body portion <NUM>. In other words, the weight-reducing portion <NUM> is formed in the shape of a hole in the ring body portion <NUM>, in a manner that an outer circumferential surface of the weight-reducing portion <NUM> defines an inner circumferential surface of the ring body portion <NUM> and an inner circumferential surface of the weight-reducing portion <NUM> defines an outer circumferential surface of a reinforcing portion <NUM> to be described later. Accordingly, the weight of the ring body portion <NUM> can be minimized.

The reinforcing portion <NUM> is a portion in contact with the weight-reducing portion <NUM>, and the outer circumferential surface of the reinforcing portion <NUM> defines the inner circumferential surface of the weight-reducing portion <NUM>. In other words, the reinforcing portion <NUM> may be formed to surround the pin coupling portion <NUM> from one side of the weight-reducing portion <NUM>. This can secure rigidity of the pin coupling portion <NUM> even while forming the weight-reducing portion <NUM> in the ring body portion <NUM>.

Also, in this case, both ends of the reinforcing portion <NUM> may be curved. This can suppress crack caused due to concentration of stress on the both ends of the reinforcing portion <NUM>, in other words, on portions of the ring body portion <NUM> where the reinforcing portion <NUM> is connected on an inner circumferential surface of an edge side.

An area of the reinforcing portion <NUM> is inversely proportional to the area of the weight-reducing portion <NUM>. For example, when the area of the reinforcing portion <NUM> is increased, the area of the weight-reducing portion <NUM> is decreased. Therefore, it is advantageous in terms of reducing the weight of the anti-rotation ring <NUM> to form the area of the reinforcing portion <NUM> as small as possible. Accordingly, the area of the reinforcing portion <NUM> may preferably be formed to be smaller than or equal to the area of the weight-reducing portion <NUM>.

The outer circumferential surface of the reinforcing portion <NUM> (i.e., the inner circumferential surface of the weight-reducing portion) may be formed to be curved. For example, the outer circumferential surface of the reinforcing portion <NUM> is formed as a circular curved surface having the same center as a center Op of the pin coupling portion <NUM>, and an outer diameter D1 of the reinforcing portion <NUM> may be about two times larger than or equal to or four times smaller than or equal to an inner diameter D2 of the pin coupling portion <NUM>.

As illustrated in <FIG>, when the outer diameter D1 of the reinforcing portion <NUM> is formed to be approximately twice as large as the inner diameter D2 of the pin coupling portion <NUM>, the area of the weight-reducing portion <NUM> is much larger than the area of the reinforcing portion <NUM>. Accordingly, the weight of the anti-rotation ring <NUM> can be greatly reduced.

As illustrated in <FIG>, when the outer diameter D1 of the reinforcing portion <NUM> is formed to be approximately four times as large as the inner diameter D2 of the pin coupling portion <NUM>, the area of the weight-reducing portion <NUM> is slightly larger than the area of the reinforcing portion <NUM>. In other words, a radial width of the reinforcing portion <NUM> is increased compared to that in the embodiment of <FIG>. This can effectively suppress damage to the pin coupling portion <NUM> (or the reinforcing portion <NUM>).

In addition, as in the embodiments of <FIG> and <FIG>, when the weight-reducing portion <NUM> is formed in the ring body portion <NUM>, an inner space of the weight-reducing portion <NUM> may define a kind of oil storage space. Accordingly, a certain amount of oil is stored between the anti-rotation ring <NUM> and the thrust plate <NUM> which constitute the substantial axial bearing surface, thereby enhancing a lubrication effect on the axial bearing surface.

Hereinafter, a description will be given of still another embodiment of an anti-rotation mechanism.

That is, in the foregoing embodiments, the weight-reducing portion of the anti-rotation ring is formed in the hole shape, but in some cases, the weight-reducing portion <NUM> may be formed in a groove shape.

<FIG> is a cut perspective view illustrating still another embodiment of an anti-rotation ring, and <FIG> and <FIG> are cross-sectional views each illustrating an installation example for the anti-rotation ring of <FIG>.

Referring to <FIG>, the basic configuration of the anti-rotation pin <NUM> and the anti-rotation ring <NUM> constituting the anti-rotation mechanism <NUM> of the scroll compressor according to this embodiment and the effects thereof are the same as those of the previous embodiment of FIG. Therefore, a detailed description thereof will be replaced with the description for the previous embodiment of FIG.

However, in this embodiment, the weight-reducing portion <NUM> is disposed in the ring body portion <NUM> of the anti-rotation ring <NUM>, in a manner of being recessed from one side surface to another side surface of the ring body portion <NUM>.

As illustrated in <FIG>, the weight-reducing portion <NUM> according to the embodiment may be recessed from an opposite side surface of the thrust plate <NUM>, namely, a rear surface of the ring body portion <NUM> to a front surface of the ring body portion <NUM> facing the thrust plate <NUM> by a preset depth. Accordingly, the anti-rotation ring <NUM> of this embodiment is provided with the weight-reducing portion <NUM> formed in the ring body portion <NUM> as in the embodiment of <FIG>, which can reduce a weight of the anti-rotation ring <NUM>, thereby improving efficiency of the gas engine heat pump including the compressor.

In addition, in this embodiment, as the weight-reducing portion <NUM> is formed in a groove shape, an opposite side surface of the weight-reducing portion <NUM> forms a kind of sliding portion <NUM>. In other words, as illustrated in the embodiment, when the weight-reducing portion <NUM> is recessed from the rear to front surfaces of the ring body portion <NUM>, the front surface of the ring body portion <NUM> in contact with the thrust plate <NUM> may be maintained in a disk shape, thereby defining the sliding portion <NUM>. Accordingly, the anti-rotation ring <NUM> has the weight-reducing portion <NUM> and the sliding portion <NUM> blocked (closed) at an opposite side of the weight-reducing portion. This can reduce surface pressure of the anti-rotation ring <NUM> with respect to the thrust plate <NUM>. With the configuration, reliability of the anti-rotation ring <NUM> can be secured and the orbiting scroll <NUM> can be more stably supported.

In addition, the weight-reducing portion <NUM> according to the embodiment may be formed as in the embodiment of <FIG>, but in this embodiment, the weight-reducing portion <NUM> may be formed to have an area significantly larger than that of the reinforcing portion <NUM>, as in the embodiment of <FIG>. In other words, in this embodiment, the sliding portion <NUM> is formed at an opposite side surface of the weight-reducing portion <NUM>, and connected to the reinforcing portion <NUM>. Accordingly, the sliding portion <NUM> may substantially have a shape extending from the reinforcing portion <NUM>, and overall rigidity of the reinforcing portion <NUM> can be increased. This can minimize the width of the reinforcing portion <NUM> and stably maintain the pin coupling portion <NUM>.

On the other hand, as illustrated in <FIG>, the weight-reducing portion <NUM> may be formed in a groove shape in the ring body portion <NUM>, and may be formed in an opposite direction to that in the embodiment of <FIG>. For example, the weight-reducing portion <NUM> may be recessed from the front surface to the rear surface of the ring body portion <NUM>. In this case, the sliding portion <NUM> is formed on the rear surface of the ring body portion <NUM>, that is, on a surface in contact with the orbiting scroll <NUM> (an inner wall surface of the ring insertion groove).

As described above, when the sliding portion <NUM> is formed on the rear surface of the ring body portion <NUM>, the sliding portion <NUM> of the ring body portion <NUM> is slidably in contact with the inner wall surface of the ring insertion groove <NUM> in an inserted state into the ring insertion groove <NUM> of the orbiting scroll <NUM>. This can suppress an increase in surface pressure of the anti-rotation ring <NUM> with respect to the orbiting scroll <NUM>, thereby securing reliability of the anti-rotation ring <NUM> and enhancing supporting force for the orbiting scroll <NUM>.

In addition, in this embodiment, the weight-reducing portion <NUM> is formed in the front surface of the ring body portion <NUM> facing the thrust plate <NUM>, as in the embodiment of <FIG>, and thus an inner space of the weight-reducing portion <NUM> may define a kind of oil storage space. Accordingly, a certain amount of oil is stored between the anti-rotation ring <NUM> and the thrust plate <NUM> which constitute the substantial axial bearing surface, thereby enhancing a lubrication effect on the axial bearing surface.

That is, in the previous embodiments, one end of the anti-rotation pin is fixed to the front housing and another end of the anti-rotation pin is rotatably inserted into the anti-rotation ring, but in some cases, the anti-rotation pin may be integrally formed with the anti-rotation ring and rotatably inserted into the front housing.

<FIG> is a cut perspective view illustrating still another embodiment of an anti-rotation ring, and <FIG> is a cross-sectional view of <FIG>.

As illustrated in <FIG> and <FIG>, the basic configuration of the anti-rotation pin <NUM> and the anti-rotation ring <NUM> constituting the anti-rotation mechanism <NUM> of the scroll compressor and the operating effects thereof are the same as those in the embodiments illustrated in <FIG>, <FIG>, <FIG>, and <FIG>, and thus a detailed description thereof will be replaced with the description of those embodiments of <FIG>, <FIG>, <FIG>, and <FIG>.

However, in this embodiment, the anti-rotation pin <NUM> may be fixedly inserted into the pin coupling portion <NUM> of the anti-rotation ring <NUM> or may extend integrally from the pin coupling portion <NUM>. For example, in this embodiment, one end of the anti-rotation pin <NUM> may be inserted into the front housing <NUM>, and another end of the anti-rotation pin <NUM> may be press-fitted to or integrally formed with the pin coupling portion <NUM> eccentric from the ring body portion <NUM> of the anti-rotation ring <NUM>.

In this case, a pin insertion groove 1122d may be formed in the scroll support surface 1122b of the front housing <NUM>, and one end of the anti-rotation pin <NUM> may be rotatably inserted into the pin insertion groove 1122d. For example, the pin insertion groove 1122d may be formed as a circular groove like the anti-rotation pin <NUM>, such that an inner diameter of the pin insertion groove 1122d is slightly larger than an outer diameter of the anti-rotation pin <NUM>. Accordingly, the anti-rotation ring <NUM> slides in the circumferential direction with respect to the ring insertion groove <NUM> disposed in the orbiting scroll <NUM>, while the anti-rotation pin <NUM> slides in the circumferential direction with respect to the pin insertion groove 1122d disposed in the front housing <NUM>. With the configuration, the orbiting scroll <NUM>, which receives the rotational force of the drive shaft <NUM>, performs an orbiting motion while the rotation of the orbiting scroll <NUM> is constrained by the anti-rotation pin <NUM> and the anti-rotation ring <NUM>.

When the anti-rotation pin <NUM> is formed integrally with the anti-rotation ring <NUM>, there is no need to separately assemble the anti-rotation pin <NUM> and the anti-rotation ring <NUM> when assembling the compressor, which can reduce the number of processes for the compressor. This may result in more reducing a manufacturing cost than those in the previous embodiments.

Meanwhile, in the previous embodiments, the example in which the oil separator <NUM> is disposed outside the casing <NUM> has been described, but the present disclosure will be equally applied even to a case in which the oil separator <NUM> is disposed inside the casing <NUM>.

In addition, in the previous embodiments, the so-called open scroll compressor in which the driving source is disposed outside the casing <NUM> has been described, but the present disclosure may be equally applied even to a so-called hermetic scroll compressor in which the drive motor constituting the driving source is disposed inside the casing <NUM>.

Also, in the previous embodiments, the example in which the thrust plate <NUM> is disposed between the front housing <NUM> and the orbiting scroll <NUM> has been described, but the present disclosure may be equally applied even when the thrust plate is excluded.

Claim 1:
A scroll compressor comprising:
a casing (<NUM>);
a fixed scroll (<NUM>) disposed inside the casing (<NUM>);
an orbiting scroll (<NUM>) engaged with the fixed scroll (<NUM>) to define compression chambers together with the fixed scroll (<NUM>) while performing an orbiting motion;
a scroll support member disposed on one side of the orbiting scroll (<NUM>) in an axial direction to support the orbiting scroll (<NUM>) in the axial direction;
an anti-rotation pin (<NUM>) disposed on a side surface of the scroll support member facing the side surface of the orbiting scroll (<NUM>);
a ring insertion groove (<NUM>) disposed in the side surface of the orbiting scroll (<NUM>); and
an anti-rotation ring (<NUM>) provided with a ring body portion (<NUM>) rotatably inserted into the ring insertion groove (<NUM>), and a pin coupling portion (<NUM>) disposed in the ring body portion (<NUM>) such that the anti-rotation pin (<NUM>) is coupled thereto,
wherein an axial thickness of the ring body portion (<NUM>) is larger than an axial depth of the ring insertion groove (<NUM>),
wherein the ring body portion (<NUM>) includes a weight-reducing portion (<NUM>) formed therein at one side of the pin coupling portion (<NUM>), and
characterized in that the weight-reducing portion (<NUM>) is formed through both side surfaces of the ring body portion (<NUM>) in the axial direction or recessed from one of the both side surfaces.