Rotary compressor having trepan and home appliance including same

Abstract

A rotary compressor according to an embodiment of the present disclosure comprises a casing (10), a motor (20) installed inside the casing (10) and including a drive shaft (30), and a compression unit (40) which is installed on a lower side of the motor (20) and compresses refrigerant according to the rotation of the drive shaft (30) to discharges the refrigerant into the casing (10). The compression unit (40) comprises a cylinder (41) in which the refrigerant is introduced, a main bearing plate (50) which is installed on the upper surface of the cylinder (41) and includes a main bearing surface (521) supporting the drive shaft (30), an upper trepan (53) formed around the lower end of the main bearing surface (521) on the lower surface of the main bearing plate (50), a sub-bearing plate (60) installed on the lower surface of the cylinder (41) and including a sub-bearing surface (621) supporting the drive shaft (30), and a lower trepan (63) formed around the upper end of the sub-bearing surface (621) on the upper surface of the sub-bearing plate (60). At least one of the upper trepan (53) and the lower trepan (63) is formed in an arc shape.

Description

Rotary compressor with trepan and home appliance including same

[0001] The present disclosure relates to a rotary compressor, and more particularly, to a rotary compressor having a trepan and a home appliance including the same.

[0002] A compressor is a mechanical device that compresses gas to increase pressure, and can be divided into reciprocating compressors and rotary compressors depending on the operating principle.

[0003] Among reciprocating compressors, there is a recipro compressor that converts the rotational motion of a motor into the linear reciprocating motion of a piston using a crank shaft and connecting rod to suck in and compress gas.

[0004] Rotary compressors include rotary compressors and scroll compressors.

[0005] A rotary compressor is formed to suck in and compress refrigerant by rotating a roller inside a cylinder of a compression unit by the rotational motion of a motor.

[0006] A scroll compressor is formed so that a rotating scroll rotates in a certain direction relative to a fixed scroll by the rotational motion of a motor, thereby sucking and compressing refrigerant.

[0007] In a rotary compressor, the compressed refrigerant is discharged inside the casing and discharged to the outside through the refrigerant discharge pipe together with oil.

[0008] A rotary compressor (1) according to one embodiment of the present disclosure may include a casing (10); a motor (20) installed within the casing (10) and including a drive shaft (30); and a compression unit (40) installed on a lower side of the motor (20) and compressing refrigerant according to the rotation of the drive shaft (30) and discharging the refrigerant into the casing (10). The compression unit (40) may include a cylinder (41) into which refrigerant is sucked; a main bearing plate (50) installed on an upper surface of the cylinder (41) and including a main bearing surface (521) supporting the drive shaft (30); an upper trefoil (53) formed on a lower surface of the main bearing plate (50) and surrounding a lower portion of the main bearing surface (521); a sub-bearing plate (60) installed on a lower surface of the cylinder (41) and including a sub-bearing surface (621) supporting the drive shaft (30); And it may include a lower trefoil (63) formed around the upper end of the sub-bearing surface (621) on the upper surface of the sub-bearing plate (60). At least one of the upper trefoil (53) and the lower trefoil (63) may be formed in an arc shape.

[0009] At this time, the compression unit (40) may further include a roller installed inside the cylinder (41) and rotating by the drive shaft (30) to compress the refrigerant; and a vane (44) having one end in contact with the roller and installed so as to be able to slide relative to the cylinder (41).

[0010] Additionally, the upper trepan (53) and the lower trepan (63) can be formed in opposite directions with respect to the vane (44) with respect to the driving shaft (30).

[0011] Additionally, the upper trepan (53) and the lower trepan (63) can be formed in an arc shape of 180 to 300 degrees.

[0012] Additionally, the upper trepan (53) and the lower trepan (63) can be formed in an asymmetrical shape.

[0013] In addition, an upper trefoil groove (54) may be formed on the lower surface of the main bearing plate (50) around the upper trefoil (53). A lower trefoil groove (64) may be formed on the upper surface of the sub bearing plate (60) around the lower trefoil (63).

[0014] Additionally, the cylinder (41) of the compression section may include an upper cylinder (410) and a lower cylinder (420).

[0015] In addition, the main bearing surface (521) and the sub bearing surface (621) may be formed as a journal bearing formed separately from the main bearing plate (50) and the sub bearing plate (60).

[0016] A rotary compressor (1) according to one aspect of the present disclosure may include a casing (10); a motor installed in the casing (10) and including a drive shaft (30); and a compression unit installed on a lower side of the motor and compressing refrigerant according to the rotation of the drive shaft (30) and discharging the refrigerant into the casing (10). The compression unit may include: a middle plate; an upper cylinder (410) installed on an upper surface of the middle plate and into which refrigerant is sucked; a lower cylinder (420) installed on a lower surface of the middle plate and into which refrigerant is sucked; a main bearing plate (50) installed on an upper surface of the upper cylinder (410) and including a main bearing surface (521) supporting the drive shaft (30); an upper trefoil plate (53) formed on a lower surface of the main bearing plate (50) and surrounding a lower end of the main bearing surface (521); a sub-bearing plate (60) installed on a lower surface of the lower cylinder (420) and including a sub-bearing surface (621); And it may include a lower trefoil (63) formed around the upper end of the sub-bearing surface (621) on the upper surface of the sub-bearing plate (60). At least one of the upper trefoil (53) and the lower trefoil (63) may be formed in an arc shape.

[0017] At this time, the compression unit may further include an upper roller (331) installed inside the upper cylinder (410) and rotating by the drive shaft (30) to compress the refrigerant; an upper vane (441) having one end in contact with the upper roller (331) and installed so as to be able to slide relative to the upper cylinder (410); a lower roller (332) installed inside the lower cylinder (420) and rotating by the drive shaft (30) to compress the refrigerant; and a lower vane (442) having one end in contact with the lower roller (332) and installed so as to be able to slide relative to the lower cylinder (420).

[0018] Additionally, the upper trepan (53) can be formed in the opposite direction to the upper vane (441) with respect to the driving shaft (30).

[0019] Additionally, the lower trepan (63) can be formed in the opposite direction to the lower vane (442) with respect to the driving shaft (30).

[0020] An appliance for controlling temperature through heat exchange with the outside using a refrigerant according to one aspect of the present disclosure may include a rotary compressor for compressing the refrigerant.

[0021] The above-described and other aspects, features, and advantages of the embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings. In the accompanying drawings:

[0022] FIG. 1 is a schematic diagram showing a refrigeration cycle used in a home appliance according to one embodiment of the present disclosure.

[0023] Fig. 2 is a cross-sectional view showing a rotary compressor according to one embodiment of the present disclosure.

[0024] FIG. 3 is a perspective view showing a compression section of a rotary compressor according to one embodiment of the present disclosure.

[0025] Fig. 4 is an exploded perspective view showing a compression unit of a rotary compressor according to one embodiment of the present disclosure.

[0026] FIG. 5 is a bottom perspective view showing a main bearing plate (50) of a rotary compressor according to one embodiment of the present disclosure.

[0027] Fig. 6 is a bottom view of the main bearing plate (50) of Fig. 5.

[0028] Fig. 7 is a perspective view showing a sub-bearing plate (60) of a rotary compressor according to one embodiment of the present disclosure.

[0029] Fig. 8 is a plan view of the sub-bearing plate (60) of Fig. 7.

[0030] FIG. 9 is a drawing showing the axial trajectory of a drive shaft on the lower surface of a main bearing plate (50) and the upper surface of a sub bearing plate (60) of a rotary compressor according to one embodiment of the present disclosure.

[0031] FIG. 10 is a drawing showing the direction of the maximum load acting on the main bearing surface (521) and the sub bearing surface (621) of a rotary compressor according to one embodiment of the present disclosure.

[0032] FIG. 11 is a drawing for explaining the positional relationship between the vane (44) of the compression section of the rotary compressor according to one embodiment of the present disclosure and the upper and lower trepans (63).

[0033] Fig. 12 is a bottom view showing a main bearing plate (50) of a rotary compressor according to one embodiment of the present disclosure.

[0034] Fig. 13 is a plan view showing a sub-bearing plate (60) of a rotary compressor according to one embodiment of the present disclosure.

[0035] Fig. 14 is a cross-sectional view showing a main bearing plate (50) of a rotary compressor according to one embodiment of the present disclosure.

[0036] Fig. 15 is a perspective view of the bottom of the main bearing plate (50) of Fig. 14.

[0037] Fig. 16 is a perspective view showing a journal bearing installed on the main bearing plate (50) of Fig. 14.

[0038] Fig. 17 is a bottom perspective view showing a main bearing plate (50) of a rotary compressor according to one embodiment of the present disclosure.

[0039] Fig. 18 is a cross-sectional view showing a rotary compressor according to one embodiment of the present disclosure.

[0040] It should be understood that the various embodiments of the present disclosure and the terminology used therein are not intended to limit the technical features described in the present disclosure to specific embodiments, but rather to encompass various modifications, equivalents, or alternatives of the embodiments.

[0041] In connection with the description of the drawings, similar reference numerals may be used for similar or related components.

[0042] The singular form of a noun corresponding to an item may include one or more of said items, unless the relevant context clearly indicates otherwise.

[0043] In this disclosure, each of the phrases "A or B", "at least one of A and B", "at least one of A or B", "A, B, or C", "at least one of A, B, and C", and "at least one of A, B, or C" may include any one of the items listed together in the corresponding phrase, or all possible combinations thereof.

[0044] The term "and / or" includes any combination of a plurality of related described elements or any one of a plurality of related described elements.

[0045] Terms such as "first," "second," or "first" or "second" may be used simply to distinguish one component from another and do not qualify the components in any other respect (e.g., importance or order).

[0046] In addition, terms such as 'front', 'rear', 'top', 'bottom', 'side', 'left', 'right', 'upper', and 'lower' used in the present disclosure are defined based on the drawings, and the shape and position of each component are not limited by these terms.

[0047] Terms such as "include" or "have" are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in the present disclosure, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0048] When a component is said to be “connected,” “coupled,” “supported,” or “in contact with” another component, this includes not only cases where the components are directly connected, coupled, supported, or in contact, but also cases where the components are indirectly connected, coupled, supported, or in contact through a third component.

[0049] When we say that a component is "on" another component, this includes not only cases where the component is in contact with the other component, but also cases where there is another component between the two components.

[0050] The present disclosure aims to provide a rotary compressor in which performance and reliability can be improved by forming an upper trefoil on a main bearing plate and forming a lower trefoil on a sub bearing plate to support a drive shaft.

[0051] Hereinafter, an embodiment of a rotary compressor according to the present disclosure will be described in detail with reference to the attached drawings.

[0052] Fig. 1 is a schematic diagram showing a refrigeration cycle used in a home appliance according to one embodiment of the present disclosure. Fig. 2 is a cross-sectional view showing a rotary compressor according to one embodiment of the present disclosure.

[0053] Referring to Figure 1, the refrigeration cycle may include four stages: compression, condensation, expansion, and evaporation. The four stages of compression, condensation, expansion, and evaporation may be performed while the refrigerant circulates through a rotary compressor (1), a condenser (2), an expansion valve (3), and an evaporator (4).

[0054] The rotary compressor (1) compresses the refrigerant gas into a high-temperature and high-pressure state and discharges it, and the high-temperature and high-pressure refrigerant gas discharged from the rotary compressor (1) flows into the condenser (2).

[0055] The condenser (2) condenses the refrigerant compressed in the rotary compressor (1) into a liquid phase, and releases heat to the surroundings through the condensation process.

[0056] The expansion valve (3) expands the high-temperature, high-pressure refrigerant condensed in the condenser (2) to a low-pressure state.

[0057] The evaporator (4) absorbs heat from the surroundings while evaporating the refrigerant expanded by the expansion valve (3), thereby cooling the surrounding air. The refrigerant gas that has absorbed heat in the evaporator (4) and has become low-temperature and low-pressure can be introduced into the rotary compressor (1). Through this refrigeration cycle, the air temperature of a certain internal space (S) can be controlled.

[0058] An appliance equipped with the above-described refrigeration cycle may be any of an air conditioner, a refrigerator, or a freezer. However, the appliance in which the rotary compressor (1) according to one embodiment of the present disclosure is used is not limited to this, and may be used in various appliances equipped with a refrigeration cycle.

[0059] The rotary compressor (1) may include a casing (10).

[0060] The casing (10) forms the exterior of the rotary compressor (1). The casing (10) can be formed as a sealed container.

[0061] The casing (10) may include a refrigerant inlet (13) through which refrigerant is introduced and a refrigerant discharge pipe (14) through which refrigerant is discharged. The refrigerant inlet (13) may be connected to the evaporator (4), and the refrigerant discharge pipe (14) may be connected to the condenser (2).

[0062] An accumulator (5) may be installed on one side of the rotary compressor (1). In this case, the refrigerant inlet (13) may be connected to the accumulator (5). Since the inlet pipe (5a) of the accumulator (5) is connected to the evaporator (4), the refrigerant discharged from the evaporator (4) may be introduced into the rotary compressor (1) through the accumulator (5).

[0063] The casing (10) may include an upper casing (11) and a lower casing (12). The upper casing (11) is joined to the upper end of the lower casing (12) to form the casing (10).

[0064] The joint between the upper casing (11) and the lower casing (12) is sealed.

[0065] A refrigerant discharge pipe (14) is provided in the upper casing (11). The refrigerant discharge pipe (14) can be provided at the top of the upper casing (11).

[0066] A refrigerant inlet (13) is provided in the lower casing (12). The refrigerant inlet (13) is connected to a compression unit (40) (see Fig. 2) installed inside the lower casing (12). Low-temperature / low-pressure refrigerant can be introduced into the refrigerant inlet (13). The refrigerant can be introduced into the compression unit (40) through the refrigerant inlet (13).

[0067] An accumulator (5) may be installed in the lower casing (12). In this case, the refrigerant inlet (13) may be connected to the discharge pipe of the accumulator (5).

[0068] A base (15) supporting the casing (10) may be provided at the bottom of the lower casing (12). The rotary compressor (1) may be installed vertically with respect to the support surface by the base (15).

[0069] Referring to FIG. 2, a rotary compressor (1) according to one embodiment of the present disclosure may include a casing (10), a motor (20), and a compression unit (40).

[0070] The casing (10) forms the exterior of the rotary compressor (1) and is a cylindrical sealed container. The casing (10) may include a lower casing (12) provided with a refrigerant inlet (13) and an upper casing (11) provided with a refrigerant discharge pipe (14).

[0071] The casing (10) is formed by combining the upper casing (11) and the lower casing (12), and the interior of the casing (10) can be sealed except for the refrigerant inlet (13) and the refrigerant discharge pipe (14). That is, the refrigerant can only flow into the interior of the casing (10) or flow out from the casing (10) to the outside through the refrigerant inlet (13) and the refrigerant discharge pipe (14).

[0072] The internal space (S) of the casing (10) accommodates high-pressure refrigerant discharged from the compression unit (40), and the high-pressure refrigerant is discharged to the outside of the casing (10) through the refrigerant discharge pipe (14).

[0073] An oil storage tank (16) for containing oil may be provided at the bottom of the casing (10).

[0074] An accumulator (5) may be installed on the outer surface of the casing (10). At this time, the refrigerant inlet (13) may be connected to the discharge pipe of the accumulator (5).

[0075] The motor (20) may be placed on the upper side inside the casing (10). The motor (20) may include a stator (21) and a rotor (22).

[0076] The stator (21) is fixed to the inner surface of the casing (10). A plurality of oil return passages may be provided between the outer surface of the stator (21) and the inner surface of the casing (10). The plurality of oil return passages may be formed at regular intervals along the outer surface of the stator (21).

[0077] Oil from the upper side of the motor (20) can move to the lower side of the motor (20) through a plurality of oil return passages provided between the stator (21) and the casing (10). Oil that has moved to the lower side of the motor (20) can be collected in an oil storage tank (16) provided at the lower side of the casing (10).

[0078] The rotor (22) can be rotatably arranged at the center of the stator (21). The rotor (22) is installed so as to maintain a certain gap with the inner surface of the stator (21).

[0079] The refrigerant discharged from the compression section (40) at the bottom of the motor (20) can move to the upper part of the motor (20) through the gap between the rotor (22) and the stator (21) and the plurality of refrigerant holes provided in the rotor.

[0080] The drive shaft (30) is inserted into and fixed to a shaft hole (29) that penetrates the center of the rotor (22). Therefore, when power is applied to the motor (20), the rotor (22) can rotate by the electromagnetic force acting between the stator (21) and the rotor (22). The drive shaft (30) can rotate integrally with the rotor (22).

[0081] When the drive shaft (30) is rotated by the motor (20), the compression unit (40) operates to compress the refrigerant.

[0082] The drive shaft (30) may be formed to extend downward from the motor (20). The lower portion of the drive shaft (30) extending downward from the motor (20) may be connected to the compression unit (40). The lower portion of the drive shaft (30) may be formed as a crank shaft to operate the compression unit (40).

[0083] The crankshaft of the drive shaft (30) may include an eccentric portion (32). Therefore, when the drive shaft (30) rotates, the eccentric portion (32) of the crankshaft rotates integrally with the drive shaft (30).

[0084] The eccentric portion (32) is formed in a cylindrical shape with a diameter larger than the diameter of the driving shaft (30), and its center line may be arranged to be eccentric with the center line of the driving shaft (30). A roller (33) may be installed on the outer circumference of the eccentric portion (32).

[0085] The drive shaft (30) can be rotatably supported by a main bearing plate (50) and a sub bearing plate (60). The main bearing plate (50) is installed to support the drive shaft (30) between the rotor (22) and the eccentric portion (32), and the sub bearing plate (60) can be installed to support the lower end of the drive shaft (30) below the eccentric portion (32).

[0086] The compression unit (40) is installed below the motor (20). The compression unit (40) can be formed so that the refrigerant can be compressed and discharged upward from the compression unit (40) according to the rotation of the drive shaft (30). The low-pressure refrigerant can be supplied to the compression unit (40) through the accumulator (5).

[0087] Hereinafter, the compression unit (40) of the rotary compressor (1) according to one embodiment of the present disclosure will be described in detail with reference to FIGS. 2 to 8.

[0088] Fig. 3 is a perspective view showing a compression section (40) of a rotary compressor (1) according to one embodiment of the present disclosure. Fig. 4 is an exploded perspective view showing a compression section (40) of a rotary compressor (1) according to one embodiment of the present disclosure.

[0089] The compression unit (40) is installed at the bottom of the casing (10) and is formed to be operated by a drive shaft (30) that rotates by a motor (20) to suck in, compress, and discharge the refrigerant.

[0090] Referring to FIGS. 2 to 4, the compression member (40) can be installed between the main bearing plate (50) and the sub bearing plate (60) that rotatably support the drive shaft (30).

[0091] The compression member (40) is installed on the lower surface of the main bearing plate (50) and may include a cylinder (41) having a flat plate shape. The cylinder (41) may be fixed to the inner surface of the casing (10).

[0092] The cylinder (41) may include an internal space (S) having a circular cross-section. That is, the internal space (S) of the cylinder (41) may be formed in a cylindrical shape.

[0093] A roller (33) installed in the eccentric portion (32) of the drive shaft (30) can be accommodated in the internal space (S) of the cylinder (41) and rotate.

[0094] The compression unit (40) may include a refrigerant inlet passage (42) connected to a refrigerant inlet port (13) provided in the casing (10). The refrigerant inlet passage (42) is formed in the cylinder (41).

[0095] The refrigerant inlet passage (42) may be formed as a through hole that connects the inner space (S) of the cylinder (41) and the outer circumference. Accordingly, the refrigerant can be introduced into the inner space (S) of the cylinder (41) through the refrigerant inlet port (13) and the refrigerant inlet passage (42).

[0096] The compression unit (40) may include a discharge port (43) through which compressed refrigerant is discharged. The discharge port (43) may be provided on the upper surface of the cylinder (41).

[0097] The cylinder (41) may include a vane (44). One end of the vane (44) contacts the roller (33) and may be installed to be slidable relative to the cylinder (41). The vane (44) contacts the roller (33) and may divide the internal space (S) into a suction chamber (S1) and a compression chamber (S2).

[0098] The vane (44) is installed so as to be movable in the internal space (S) of the cylinder (41). The vane (44) is arranged so that one end radially contacts the roller (33), and the internal space (S) of the cylinder (41) can be divided into a suction chamber (S1) and a compression chamber (S2).

[0099] The cylinder (41) may include a guide slot (45) that guides the vane (44) so ​​that the vane (44) reciprocates linearly in a radial direction while in contact with the roller (33).

[0100] The guide slot (45) is formed in a slot shape from the inner surface of the cylinder (41) toward the outer surface, and can guide the vane (44) so ​​that the vane (44) can move linearly back and forth by the rotation of the roller (33).

[0101] An elastic member (46) that continuously applies elastic force toward the roller (33) with respect to the vane (44) may be installed at the inner end of the guide slot (45). Accordingly, when the roller (33) rotates in the internal space (S) due to the rotation of the driving shaft (30), one end of the vane (44) can be in continuous contact with the roller (33) by the elastic member (46).

[0102] Therefore, when the roller (33) rotates, the suction chamber (S1) and the compression chamber (S2) can be spatially partitioned continuously by the vane (44).

[0103] The roller (33) is arranged within the internal space (S) of the cylinder (41) and can rotate along the inner circumferential surface of the cylinder (41) forming the internal space (S) of the cylinder (41).

[0104] The roller (33) is formed in a cylindrical shape, and an eccentric portion (32) of a drive shaft (30) can be installed inside the roller (33). Therefore, when the drive shaft (30) rotates, the eccentric portion (32) rotates, thereby rotating the roller (33).

[0105] The internal space (S) of the cylinder (41) may include a suction chamber (S1) and a compression chamber (S2) separated by a vane (44). The suction chamber (S1) and the compression chamber (S2) may be changed and created by a roller (33) rotating in the internal space (S) of the cylinder (41).

[0106] The suction chamber (S1) is connected to the refrigerant inlet passage (42) and can receive refrigerant introduced through the refrigerant inlet passage (42).

[0107] The compression chamber (S2) is a space where the introduced refrigerant is compressed by the rotational movement of the roller (33) and is connected to the discharge port (43).

[0108] Therefore, when the roller (33) is rotated by the drive shaft (30), the refrigerant is introduced into the internal space (S) of the cylinder (41) through the refrigerant inlet passage (42), compressed by the roller (33), and then discharged through the discharge port (43).

[0109] A main bearing plate (50) is installed on the upper surface of the cylinder (41), and a sub bearing plate (60) is installed on the lower surface of the cylinder (41). That is, the cylinder (41) is installed between the main bearing plate (50) and the sub bearing plate (60). Therefore, the upper portion of the internal space (S) of the cylinder (41) can be covered by the main bearing plate (50), and the lower portion can be covered by the sub bearing plate (60).

[0110] The main bearing plate (50) and the sub bearing plate (60) can be connected to the cylinder (41) with a plurality of bolts (49). The cylinder (41) is fixed to the inner circumferential surface of the casing (10). Therefore, when the main bearing plate (50) and the sub bearing plate (60) are fixed to the cylinder (41), the main bearing plate (50) and the sub bearing plate (60) can be fixed to the casing (10).

[0111] The main bearing plate (50) rotatably supports the drive shaft (30) and can be formed to block the upper part of the internal space (S) of the cylinder (41).

[0112] The main bearing plate (50) may be provided with a hole (57) that communicates with the discharge port (43) of the cylinder (41). Accordingly, the refrigerant discharged through the discharge port (43) of the cylinder (41) can be discharged to the upper side of the main bearing plate (50) through the hole (57) of the main bearing plate (50).

[0113] The main bearing plate (50) may include a discharge valve (58) that opens and closes the hole (57). Accordingly, the hole of the main bearing plate (50) can be opened and closed by the discharge valve (58). When the refrigerant introduced into the cylinder (41) is compressed above a certain pressure, the discharge valve (58) opens so that the refrigerant can be discharged to the upper side of the main bearing plate (50).

[0114] The main bearing plate (50) may include a plurality of bolt holes (59) provided along the circumferential direction of the main bearing plate (50).

[0115] A muffler (70) may be installed on the upper side of the main bearing plate (50). The muffler (70) is formed to reduce noise generated by refrigerant discharged through the hole (57) of the main bearing plate (50).

[0116] The muffler (70) may be provided with a plurality of bolt holes (71) corresponding to the plurality of bolt holes (59) of the main bearing plate (50) along the edge. The muffler (70) may include a refrigerant opening (72) for discharging refrigerant with reduced noise.

[0117] The cylinder (41) may be provided with a plurality of tapped holes (48) corresponding to a plurality of bolt holes (59) of the main bearing plate (50). When a plurality of bolts (49) are fastened to the plurality of tapped holes (48) of the cylinder (41), the muffler (70) and the main bearing plate (50) may be fixed to the cylinder (41) by the plurality of bolts (49).

[0118] The refrigerant discharged through the hole (57) of the main bearing plate (50) can pass through the inside of the muffler (70) with reduced noise, and then be discharged through the refrigerant opening (72) of the muffler (70) into the upper side of the muffler (70), i.e., the space between the motor (20) and the compression unit (40).

[0119] Hereinafter, with reference to FIGS. 5 and 6, the main bearing plate (50) of the rotary compressor (1) according to one embodiment of the present disclosure will be described in detail.

[0120] Fig. 5 is a bottom perspective view showing a main bearing plate (50) of a rotary compressor (1) according to one embodiment of the present disclosure. Fig. 6 is a bottom view of the main bearing plate (50) of Fig. 5.

[0121] Referring to FIGS. 5 and 6, the main bearing plate (50) may be formed in a circular shape. A through hole (52) may be formed in the center of the main bearing plate (50). A drive shaft (30) may be inserted into the through hole (52). The main bearing plate (50) is formed so as to cover the upper end of the internal space (S) of the cylinder (41).

[0122] The main bearing plate (50) may include a main boss (51). The main boss (51) may extend upward from the upper surface of the main bearing plate (50). The main boss (51) may extend vertically from the center of the main bearing plate (50). A through hole may also be formed in the center of the main boss (51). That is, the main boss (51) may be formed in an approximately hollow cylindrical shape. The through hole of the main boss (51) may be connected to the through hole (52) of the main bearing plate (50) to form one through hole.

[0123] The inner surface of the through hole (52) of the main bearing plate (50) and the inner surface of the through hole of the main boss can form a main bearing surface (521). The main bearing surface (521) can rotatably support the drive shaft (30).

[0124] An upper trefoil (53) may be provided on the lower surface of the main bearing plate (50). The upper trefoil (53) may be formed around the lower portion of the main bearing surface (521) on the lower surface of the main bearing plate (50). The upper trefoil (53) may be formed in an arc shape. That is, the upper trefoil (53) may not be formed in a complete ring shape, but may be formed in a shape in which a portion is removed from the ring shape.

[0125] The upper trefoil (53) can be formed with the same thickness along its entire length. The upper trefoil (53) is spaced apart from the main bearing plate (50) by a certain distance. That is, the side surface of the upper trefoil (53) is not connected to the main bearing plate (50). In addition, both ends of the upper trefoil (53) are not connected to the main bearing plate (50).

[0126] An upper trefoil groove (54) may be formed on the lower surface of the main bearing plate (50). The upper trefoil groove (54) may be formed around the upper trefoil (53). The upper trefoil groove (54) may be formed in a circular shape concentric with the through hole (52) of the main bearing plate (50). The diameter of the upper trefoil groove (54) is larger than the diameter of the through hole (52) of the main bearing plate (50). The upper trefoil groove (54) may be formed at a certain depth on the lower surface of the main bearing plate (50). For example, the upper trefoil groove (54) may be formed shallower than the thickness of the main bearing plate (50). The upper trefoil groove (54) may form a step with the lower surface of the main bearing plate (50) and the through hole (52).

[0127] The upper trefoil (53) may be formed in a shape that protrudes from the bottom surface (541) of the upper trefoil groove (54). The upper trefoil (53) may be formed so as not to protrude from the lower surface of the main bearing plate (50). That is, the upper trefoil (53) may be formed at the same height as the lower surface of the main bearing plate (50) or may be formed lower.

[0128] The upper trefoil (53) can be formed in an arc shape along the circumference of the through hole (52) of the main bearing plate (50) on the bottom surface (541) of the upper trefoil (53). The upper trefoil (53) is not formed along the entire circumference of the through hole (52). Therefore, a portion of the bottom surface (541) of the upper trefoil groove (54) where the upper trefoil (53) is not formed along the circumference of the through hole (52) may exist. In the portion of the upper trefoil groove (54) where the upper trefoil (53) does not exist, the bottom surface (541) of the upper trefoil groove (54) and the inner surface of the through hole (52), i.e., the main bearing surface (521), can directly and vertically meet.

[0129] The upper trefoil (53) may be formed as an arc-shaped wall protruding from the bottom surface (541) of the upper trefoil groove (54) along the through hole (52). The upper trefoil (53) may be formed with the same thickness along the entire length. A constant gap may exist between the inner surface of the upper trefoil (53) and the upper trefoil groove (54). That is, a curved groove may be formed between the inner surface of the upper trefoil (53) and the upper trefoil groove (54). Therefore, the upper trefoil (53) is not connected to the inner surface of the upper trefoil groove (54).

[0130] The inner surface of the upper trefoil (53), i.e., the surface that comes into contact with the drive shaft (30), can form a part of the main bearing surface (521). Therefore, the upper trefoil (53) can rotatably support the drive shaft (30).

[0131] The upper trefoil (53) may be formed on the opposite side to the vane (44) of the cylinder (41) with respect to the drive shaft (30). That is, the upper trefoil (53) may be formed on the opposite side to the vane (44) of the cylinder (41) with respect to the center of the through hole (52) of the main bearing plate (50). Accordingly, the upper trefoil (53) may not be formed in the upper trefoil groove (54) closer to the vane (44) with respect to the center of the through hole (52) of the main bearing plate (50).

[0132] Hereinafter, with reference to FIGS. 7 and 8, a sub-bearing plate (60) of a rotary compressor (1) according to one embodiment of the present disclosure will be described in detail.

[0133] Fig. 7 is a perspective view showing a sub-bearing plate (60) of a rotary compressor (1) according to one embodiment of the present disclosure. Fig. 8 is a plan view of the sub-bearing plate (60) of Fig. 7.

[0134] A sub-bearing plate (60) may be installed on the lower surface of the cylinder (41). The sub-bearing plate (60) may be formed to rotatably support the lower portion of the driving shaft (30) and block the lower portion of the internal space (S) of the cylinder (41).

[0135] Referring to FIGS. 7 and 8, the sub-bearing plate (60) may be formed in a circular shape. A through hole (62) may be formed in the center of the sub-bearing plate (60). A drive shaft (30) may be inserted into the through hole (62). The sub-bearing plate (60) is formed so as to cover the lower portion of the internal space (S) of the cylinder (41).

[0136] The sub-bearing plate (60) may include a sub-boss (61). The sub-boss (61) may extend downward from the lower surface of the sub-bearing plate (60). The sub-boss (61) may extend vertically from the center of the sub-bearing plate (60). A through hole may also be formed in the center of the sub-boss (61). That is, the sub-boss (61) may be formed in an approximately hollow cylindrical shape. The through hole of the sub-boss (61) may be connected to the through hole (62) of the sub-bearing plate (60) to form one through hole.

[0137] The inner surface of the through hole (62) of the sub-bearing plate (60) and the inner surface of the through hole of the sub-boss (61) can form a sub-bearing surface (621). The sub-bearing surface (621) can rotatably support the driving shaft (30).

[0138] A lower trefoil (63) may be provided on the upper surface of the sub-bearing plate (60). The lower trefoil (63) may be formed identically or similarly to the upper trefoil (53) of the main bearing plate (50) described above.

[0139] The lower trefoil (63) may be formed around the upper portion of the sub-bearing surface (621) on the upper surface of the sub-bearing plate (60). The lower trefoil (63) may be formed in an arc shape. That is, the lower trefoil (63) may not be formed in a complete ring shape, but may be formed in a shape in which a portion is removed from the ring shape.

[0140] The lower trefoil (63) can be formed with the same thickness along its entire length. The lower trefoil (63) is spaced apart from the sub-bearing plate (60) by a certain distance. That is, the side surfaces of the lower trefoil (63) are not connected to the sub-bearing plate (60). In addition, both ends of the lower trefoil (63) are not connected to the sub-bearing plate (60).

[0141] A lower trefoil groove (64) may be formed on the upper surface of the sub-bearing plate (60). The lower trefoil groove (64) may be formed around the lower trefoil (63). The lower trefoil groove (64) may be formed in a circular shape concentric with the through hole (62) of the sub-bearing plate (60). The diameter of the lower trefoil groove (64) is larger than the diameter of the through hole (62) of the sub-bearing plate (60). The lower trefoil groove (64) may be formed at a predetermined depth on the upper surface of the sub-bearing plate (60). For example, the lower trefoil groove (64) may be formed shallower than the thickness of the sub-bearing plate (60). Therefore, the lower trefoil groove (64) may form a step with the upper surface of the sub-bearing plate (60) and the through hole (62).

[0142] The lower trefoil (63) may be formed in a shape that protrudes from the bottom surface (641) of the lower trefoil groove (64). The lower trefoil (63) may be formed so as not to protrude from the upper surface of the sub-bearing plate (60). That is, the lower trefoil (63) may be formed at the same height as the upper surface of the sub-bearing plate (60) or may be formed lower.

[0143] The lower trefoil (63) can be formed in an arc shape along the circumference of the through hole (62) of the sub-bearing plate (60) on the bottom surface (641) of the lower trefoil groove (64). The lower trefoil (63) is not formed along the entire circumference of the through hole (62). Therefore, there may be a portion on the bottom surface (641) of the lower trefoil groove (64) along the circumference of the through hole (62) where the lower trefoil (63) is not formed. In the portion of the lower trefoil groove (64) where the lower trefoil (63) does not exist, the bottom surface (641) of the lower trefoil groove (64) and the inner surface of the through hole (62), i.e., the sub-bearing surface (621), can directly and vertically meet.

[0144] The lower trefoil (63) may be formed as an arc-shaped wall protruding from the bottom surface (641) of the lower trefoil groove (64) along the through hole (62). The lower trefoil (63) may be formed with the same thickness throughout its entire length. A constant gap may exist between the inner surface of the lower trefoil (63) and the lower trefoil groove (64). That is, a curved groove may be formed between the inner surface of the lower trefoil (63) and the lower trefoil groove (64). Therefore, the lower trefoil (63) is not connected to the inner surface of the lower trefoil groove (64).

[0145] The inner surface of the lower trefoil (63), i.e., the surface that comes into contact with the drive shaft (30), can form a part of the sub-bearing surface (621). Accordingly, the lower trefoil (63) can rotatably support the drive shaft (30).

[0146] The lower trefoil (63) may be formed on the opposite side to the vane (44) of the cylinder (41) with respect to the drive shaft (30). That is, the lower trefoil (63) may be formed on the opposite side to the vane (44) of the cylinder (41) with respect to the center of the through hole (62) of the sub-bearing plate (60). Accordingly, the lower trefoil (63) may not be formed in the lower trefoil groove (64) closer to the vane (44) with respect to the center of the through hole (62) of the sub-bearing plate (60).

[0147] When the rotary compressor (1) operates and the drive shaft (30) rotates, the center trajectory of the drive shaft (30) may be biased to one side. Accordingly, a concentrated load may be applied to the lower portion of the main bearing surface (521) adjacent to the compression section (40) and the upper portion of the sub-bearing surface (621).

[0148] FIG. 9 is a drawing showing the trajectory of the center of the drive shaft (30) on the lower surface of the main bearing plate (50) and the upper surface of the sub bearing plate (60) of the rotary compressor (1) according to one embodiment of the present disclosure.

[0149] In Fig. 9, the numbers on the circumference of the circle represent angles, and the unit is degree. The vertical axis represents the radius of the central trajectory of the drive shaft (30), and the unit is μm.

[0150] In addition, in FIG. 9, the dotted line (C1) represents a trajectory along which the center of the cross-section of the drive shaft (30) that is flush with the lower surface of the main bearing plate (50) moves. That is, the dotted line (C1) represents a trajectory along which the center of the cross-section of the drive shaft (30) that forms the flush with the lower surface of the main bearing plate (50) moves while the drive shaft (30) rotates once. The solid line (C2) represents a trajectory along which the center of the cross-section of the drive shaft (30) that forms the flush with the upper surface of the sub bearing plate (60) moves. That is, the solid line (C2) represents a trajectory along which the center of the cross-section of the drive shaft (30) that forms the flush with the upper surface of the sub bearing plate (60) moves while the drive shaft (30) rotates once.

[0151] In addition, the vane (44) of the cylinder (41) is located at the 0 degree position in FIG. 9. That is, the center line of the vane (44) of the cylinder (41) is located at the 0 degree position in FIG. 9. The center (C) of the circle may coincide with the center of the internal space (S) of the cylinder (41), the center of the through hole (52) of the main bearing plate (50), and the center of the through hole (62) of the sub bearing plate (60).

[0152] Referring to Fig. 9, the center of the drive shaft (30) supported by the lower surface of the main bearing plate (50), i.e., the lower side of the main bearing surface (521), is located on the opposite side of the vane (44) of the cylinder (41) with respect to the center of the through hole (52) of the main bearing plate (50). That is, while the drive shaft (30) rotates once, the drive shaft (30) rotates while being pushed to the opposite side of the vane (44). As a result, the drive shaft (30) rotates while being in close contact with the main bearing surface (521) opposite to the vane (44). Therefore, a concentrated load is generated by the drive shaft (30) on the part of the main bearing surface (521) opposite to the vane (44).

[0153] The center of the drive shaft (30) supported by the upper surface of the sub-bearing plate (60), i.e., the upper end of the sub-bearing surface (621), is located on the opposite side of the vane (44) of the cylinder (41) with respect to the center of the through hole (62) of the sub-bearing plate (60). That is, while the drive shaft (30) rotates once, the drive shaft (30) rotates while being pushed to the opposite side of the vane (44). As a result, the drive shaft (30) rotates while being in close contact with the sub-bearing surface (621) opposite to the vane (44). Therefore, a concentrated load is generated by the drive shaft (30) on the portion of the sub-bearing surface (621) opposite to the vane (44).

[0154] Fig. 10 is a drawing showing the direction of the maximum load acting on the main bearing surface (521) and the sub bearing surface (621) of the rotary compressor (1) according to one embodiment of the present disclosure. Fig. 11 is a drawing for explaining the positional relationship between the vane (44) of the compression section and the upper trefoil (53) and the lower trefoil (63) of the rotary compressor (1) according to one embodiment of the present disclosure.

[0155] Referring to Fig. 10, it can be seen that, as described above, concentrated loads (F1, F2) are generated at the lower end of the main bearing surface (521) and the upper end of the sub bearing surface (621). The concentrated loads (F1, F2) are applied in the opposite direction to the vane (44) of the cylinder (41) from the center of the drive shaft (30).

[0156] Specifically, the upper concentrated load (F1) can be applied to a portion of the lower part of the main bearing surface (521) located on the opposite side of the vane (44), i.e., facing the vane (44). Therefore, the portion of the lower part of the main bearing surface (521) on the opposite side of the vane (44) functions as a bearing. However, the portion of the main bearing surface (521) on the vane (44) side does not function as a bearing because it is not subject to force by the drive shaft (30). Therefore, the upper trefoil (53) can be formed on the opposite side of the vane (44), as illustrated in FIG. 11. The upper trefoil (53) is not formed on the vane (44) side.

[0157] The upper trefoil (53) may be formed as a wall in the shape of an arc at a certain angle on the opposite side of the vane (44). The length of the upper trefoil (53) may be appropriately determined depending on the size of the load (F1) applied to the upper trefoil (53). For example, the upper trefoil (53) may be formed in the shape of an arc of 180 to 300 degrees. At this time, the center of the arc shape is the center of the through hole (52) of the main bearing plate (50).

[0158] Fig. 12 is a bottom view showing a main bearing plate (50) of a rotary compressor (1) according to one embodiment of the present disclosure.

[0159] Referring to Fig. 12, the upper trefoil (53) may be formed as an arc of ±90 degrees to ±150 degrees based on a center line (CL1) located opposite the vane (44) of the cylinder (41) and passing through the center (C) of the through hole (52) of the main bearing plate (50). That is, the arc may be formed to have an angle (A) of at least -90 degrees to +90 degrees and at most -150 degrees to +150 degrees based on the center line (CL1). At this time, the center line (CL1) opposite the vane (44) forms a straight line with the center line (CL2) of the vane (44). The curvature of the upper trefoil (53) may be the same as the curvature of the main bearing surface (521).

[0160] In this case, the angle (B) of the bottom surface (541) of the upper trefoil groove (54) that is not formed of the upper trefoil (53) may be ±30 degrees to ±90 degrees with respect to the center line (CL2) of the vane (44). That is, the angle (B) of the bottom surface (541) of the upper trefoil groove (54) that is not formed of the upper trefoil (53) may be at least -30 degrees to +30 degrees and at most -90 degrees to +90 degrees with respect to the center line (CL2) of the vane (44). In other words, the lower portion of the main bearing surface (521) in the direction of the vane (44) may be removed by ±30 degrees to ±90 degrees with respect to the center line (CL2) of the vane (44).

[0161] Referring back to FIG. 10, the lower concentrated load (F2) can be applied to the upper portion of the sub-bearing surface (621) located on the opposite side of the vane (44), i.e., facing the vane (44). Therefore, the upper portion of the sub-bearing surface (621) on the opposite side of the vane (44) functions as a bearing. However, the portion of the sub-bearing surface (621) on the vane (44) side does not function as a bearing because it is not subject to force by the drive shaft (30). Therefore, the lower trefoil (63) can be formed on the opposite side of the vane (44), as illustrated in FIG. 11. The lower trefoil (63) is not formed on the vane (44) side.

[0162] The lower trefoil (63) may be formed as a wall in the shape of an arc at a certain angle on the opposite side of the vane (44). The length of the lower trefoil (63) may be appropriately determined depending on the size of the load (F2) applied to the lower trefoil (63). For example, the lower trefoil (63) may be formed in the shape of an arc of 180 to 300 degrees. At this time, the center of the arc shape is the center of the through hole (62) of the sub-bearing plate (60).

[0163] Fig. 13 is a plan view showing a sub-bearing plate (60) of a rotary compressor (1) according to one embodiment of the present disclosure.

[0164] Referring to Fig. 13, the lower trefoil (63) may be formed as an arc of ±90 degrees to ±150 degrees with respect to a center line (CL1) located opposite the vane (44) of the cylinder (41) and passing through the center (C) of the through hole (62) of the sub-bearing plate (60). That is, the arc may be formed to have an angle (A) of at least -90 degrees to +90 degrees and at most -150 degrees to +150 degrees with respect to the center line (CL1). At this time, the center line (CL1) opposite the vane (44) forms a straight line with the center line (CL2) of the vane (44). The curvature of the lower trefoil (63) may be the same as the curvature of the sub-bearing surface (621).

[0165] In this case, the angle (B) of the bottom surface (641) of the lower trefoil groove (64) where the lower trefoil (63) is not formed may be ±30 degrees to ±90 degrees with respect to the center line (CL2) of the vane (44). That is, the angle of the bottom surface (641) of the lower trefoil groove (64) where the lower trefoil (63) is not formed may be at least -30 degrees to +30 degrees and at most -90 degrees to +90 degrees with respect to the center line (CL2) of the vane (44). In other words, in the direction of the vane (44), the upper portion of the sub-bearing surface (621) may be removed by ±30 degrees to ±90 degrees with respect to the center line (CL2) of the vane (44).

[0166] In this way, when the upper trefoil (53) is formed on the main bearing plate (50) and the lower trefoil (63) is formed on the sub bearing plate (60), the trefoil performing the bearing function exists only in the portion where the load is applied by the drive shaft (30), and the trefoil performing the bearing function does not exist in the portion where the load is not applied. Therefore, compared to the conventional technology that supports the entire circumference of the drive shaft (30) with a bearing, the rotary compressor (1) according to one embodiment of the present disclosure has a reduced bearing area that supports the rotation of the drive shaft (30), so that the frictional loss due to the bearing can be reduced. Reducing the frictional loss of the bearing can improve the performance of the rotary compressor (1).

[0167] In addition, since the rotary compressor (1) according to one embodiment of the present disclosure has an upper trefoil (53) and a lower trefoil (63) that support only a portion of the drive shaft (30), it can be easily deformed and then restored compared to a ring-shaped trefoil that surrounds the entire circumference of the drive shaft (30). Therefore, the upper trefoil (53) and the lower trefoil (63) according to one embodiment of the present disclosure can effectively support concentrated loads (F1, F2).

[0168] In other words, unlike the present disclosure, when the trefoil is formed in an annular shape, the rigidity of the trefoil is high, so cracks may occur on the bearing surface due to concentrated load. However, in the rotary compressor (1) according to the present disclosure, the upper trefoil (53) and the lower trefoil (63) are formed in an arc shape, so the rigidity is low, so the occurrence of cracks on the bearing surface can be prevented or minimized. Therefore, the rotary compressor (1) according to one embodiment of the present disclosure can improve reliability compared to a rotary compressor (1) having an annular trefoil structure.

[0169] In the above, the case where both the upper trefoil (53) of the main bearing plate (50) and the lower trefoil (63) of the sub-bearing plate (60) are formed in an arc shape has been described, but the present disclosure is not limited thereto. As another example, the upper trefoil (53) of the main bearing plate (50) may be formed in an arc shape, and the lower trefoil (63) of the sub-bearing plate (60) may be formed in an annular shape. Alternatively, the lower trefoil (63) of the sub-bearing plate (60) may be formed in an arc shape, and the upper trefoil (53) of the main bearing plate (50) may be formed in an annular shape.

[0170] In the above, the case where the inner surface of the through hole (52) of the main bearing plate (50) and the inner surface of the through hole (62) of the sub bearing plate (60) are formed as a bearing surface has been illustrated and described, but the present disclosure is not limited thereto. As another example, the bearing surface may be formed as a separate journal bearing. That is, the bearing surface may be formed by inserting a separately formed journal bearing into the through hole (52) of the main bearing plate (50) and the through hole (62) of the sub bearing plate (60).

[0171] Hereinafter, a main bearing plate (50) using a separate journal bearing (55) will be described with reference to FIGS. 14 to 16.

[0172] Fig. 14 is a cross-sectional view showing a main bearing plate (50) of a rotary compressor (1) according to one embodiment of the present disclosure. Fig. 15 is a bottom perspective view of the main bearing plate (50) of Fig. 14. Fig. 16 is a perspective view showing a journal bearing (55) installed on the main bearing plate (50) of Fig. 14.

[0173] The main bearing plate (50) according to the present embodiment can be formed similarly to the main bearing plate (50) according to the above-described embodiment. Therefore, the following description focuses on the differences.

[0174] Referring to FIGS. 14 to 16, the main bearing plate (50) may be formed in a circular shape. A through hole (52) may be formed in the center of the main bearing plate (50). A drive shaft (30) may be inserted into the through hole (52). The main bearing plate (50) is formed so as to cover the upper end of the internal space (S) of the cylinder (41).

[0175] The main bearing plate (50) may include a main boss (51). The main boss (51) may extend upward from the upper surface of the main bearing plate (50). The main boss (51) may extend vertically from the center of the main bearing plate (50). A through hole may also be formed in the center of the main boss (51). That is, the main boss (51) may be formed in an approximately hollow cylindrical shape. The through hole of the main boss (51) may be connected to the through hole (52) of the main bearing plate (50) to form one through hole.

[0176] A ring-shaped trefoil (56) may be formed around the through hole (52) on the lower surface of the main bearing plate (50). A ring-shaped trefoil groove (54) may be formed around the trefoil (56).

[0177] A journal bearing (55) can be inserted into the through hole (52) of the main bearing plate (50). The journal bearing (55) is formed so as to support the rotation of the drive shaft (30).

[0178] A portion of the lower portion of the journal bearing (55) adjacent to the lower surface of the main bearing plate (50) may be removed. That is, a cut portion (551) cut in a substantially flat-bottomed channel shape may be formed in a portion of the lower portion of the journal bearing (55).

[0179] At this time, the journal bearing (55) can be installed in the through hole (52) of the main bearing plate (50) so that the cut-out (551) of the journal bearing (55) faces the vane (44) of the cylinder (41). Then, the arc-shaped portion of the lower portion of the journal bearing (55) can support the drive shaft (30) in the same way as the upper trefoil (53) of the main bearing plate (50) according to the above-described embodiment.

[0180] The main bearing plate (50) having this structure can reduce friction loss due to the bearing because the bearing area that supports the rotation of the drive shaft (30) is reduced.

[0181] As another example, as illustrated in FIG. 17, a portion (561) corresponding to the cut portion (551) of the journal bearing (55) in the annular trepan (56) can be removed.

[0182] Fig. 17 is a bottom perspective view showing a main bearing plate (50) of a rotary compressor (1) according to one embodiment of the present disclosure.

[0183] Referring to Fig. 17, an arc-shaped upper trefoil (56) is formed in a trefoil groove (54) on the lower surface of the main bearing plate (50), and a journal bearing (55) having a cutout (551) is inserted into a through hole (52) of the main bearing plate (50). At this time, the journal bearing (55) is installed in the through hole (52) of the main bearing plate (50) so that the cutout (551) is located in a portion (561) where the upper trefoil (56) is not formed.

[0184] The main bearing plate (50) illustrated in Fig. 17 differs from the upper trefoil (53) of the main bearing plate (50) according to the embodiment described above in that the inner surface of the upper trefoil (56) is not formed as a bearing surface. A separately formed journal bearing (55) is installed on the inner surface of the upper trefoil (56) of the main bearing plate (50) of Fig. 17.

[0185] The main bearing plate (50) having this structure has a low rigidity due to the upper trefoil (56) and the lower part of the journal bearing (55) being formed in an arc shape, so it can effectively support concentrated loads, thereby preventing or minimizing the occurrence of cracks on the bearing surface.

[0186] Although FIGS. 14 to 17 illustrate and explain the main bearing plate (50) as an example, the structure of the main bearing plate (50) can be equally applied to the sub bearing plate (60).

[0187] Hereinafter, a rotary compressor (1) according to another embodiment of the present disclosure will be described with reference to FIG. 18.

[0188] Fig. 18 is a cross-sectional view showing a rotary compressor (1) according to one embodiment of the present disclosure.

[0189] Referring to FIG. 18, a rotary compressor (1) according to one embodiment of the present disclosure may include a casing (10), a motor (20), and a compression unit (40).

[0190] The rotary compressor (1) of Fig. 18 is identical to the rotary compressor (1) according to the above-described embodiment, except that the compression section (40) includes two cylinders (410, 420). Therefore, the description of the casing (10) and the motor (20) will be omitted below, and the description will focus on the compression section (40).

[0191] Referring to FIG. 18, the compression member (40) can be installed between the main bearing plate (50) and the sub bearing plate (60) that rotatably support the drive shaft (30).

[0192] The compression unit (40) may include an upper compression unit (401), a lower compression unit (402), and an intermediate plate (430) provided between the upper compression unit (401) and the lower compression unit (402).

[0193] The upper compression section (401) is formed so as to be able to suck and compress refrigerant according to the rotation of the drive shaft (30). The lower compression section (402) is provided below the upper compression section (401) and is formed so as to be able to suck and compress refrigerant according to the rotation of the drive shaft (30).

[0194] The upper compression member (401) is installed on the upper surface of the middle plate (430) and may include an upper cylinder (410) having a flat plate shape. The upper cylinder (410) may include an internal space (S) having a circular cross-section.

[0195] The upper cylinder (410) may include a refrigerant inlet passage (412) connected to a refrigerant inlet (13) provided in the casing (10). The refrigerant inlet passage (412) may be formed as a through hole that communicates the inner space (S) of the upper cylinder (410) with the outer circumference. Accordingly, the refrigerant may be introduced into the inner space (S) of the upper cylinder (410) through the refrigerant inlet (13) and the refrigerant inlet passage (412).

[0196] The upper cylinder (410) may include an upper discharge port through which compressed refrigerant is discharged. The upper discharge port may be provided on the upper surface of the upper cylinder (410).

[0197] The upper roller (331) is arranged within the inner space (S) of the upper cylinder (410) and can rotate along the inner circumference of the upper cylinder (410) forming the inner space (S) of the upper cylinder (410).

[0198] The upper roller (331) is formed in a cylindrical shape, and the upper eccentric portion (321) of the drive shaft (30) can be installed inside the upper roller (331). Therefore, when the drive shaft (30) rotates, the upper eccentric portion (321) rotates, thereby rotating the upper roller (331).

[0199] The upper cylinder (410) may include an upper vane (441). One end of the upper vane (441) may contact the upper roller (331) and may be installed to be slidable relative to the upper cylinder (410).

[0200] The internal space (S) of the upper cylinder (410) may include a suction chamber (S1) and a compression chamber (S2) partitioned by an upper vane (441). The suction chamber (S1) is connected to a refrigerant inlet passage (412), and refrigerant introduced through the refrigerant inlet passage (412) can be received. The compression chamber (S2) is a space where the introduced refrigerant is compressed by the rotational movement of the upper roller (331), and is connected to the upper discharge port (413).

[0201] Accordingly, when the upper roller (331) is rotated by the drive shaft (30), the refrigerant is introduced into the internal space (S) of the upper cylinder (410) through the refrigerant inlet passage (412), compressed by the upper roller (331), and then discharged through the upper discharge port.

[0202] The lower compression member (402) is installed on the lower surface of the middle plate (430) and may include a lower cylinder (420) having a flat plate shape. The lower cylinder (420) may include an internal space (S) having a circular cross-section.

[0203] The lower compression section (402) may include a refrigerant inlet passage (422) connected to a refrigerant inlet port (13) provided in the casing (10). The refrigerant inlet passage (422) is formed in the lower cylinder (420).

[0204] The refrigerant inlet passage (422) may be formed as a through hole that connects the inner space (S) of the lower cylinder (420) and the outer circumference. Accordingly, the refrigerant may be introduced into the inner space (S) of the lower cylinder (420) through the refrigerant inlet port (13) and the refrigerant inlet passage (422).

[0205] The lower compression unit (42) may include a lower discharge port through which compressed refrigerant is discharged. The lower discharge port may be provided on the lower surface of the lower cylinder (420). Accordingly, the refrigerant compressed by the lower compression unit (42) may be discharged downward from the lower compression unit (42) through the lower discharge port.

[0206] The lower roller (332) is arranged within the inner space (S) of the lower cylinder (420) and can rotate along the inner circumference of the lower cylinder (420) forming the inner space (S) of the lower cylinder (420).

[0207] The lower roller (332) is formed in a cylindrical shape, and the lower eccentric portion (322) of the drive shaft (30) can be installed inside the lower roller (332). Therefore, when the drive shaft (30) rotates, the lower eccentric portion (322) rotates, thereby rotating the lower roller (332).

[0208] The lower cylinder (420) may include a lower vane (442). One end of the lower vane (442) may contact the lower roller (332) and may be installed to be slidable relative to the lower cylinder (420).

[0209] The internal space (S) of the lower cylinder (420) may include a suction chamber (S1) and a compression chamber (S2) partitioned by a lower vane (442). The suction chamber (S1) is connected to a refrigerant inlet passage (422), and refrigerant introduced through the refrigerant inlet passage (422) can be received. The compression chamber (S2) is a space where the introduced refrigerant is compressed by the rotational movement of the lower roller (332), and is connected to the lower discharge port.

[0210] When the lower roller (332) is rotated by the drive shaft (30), the refrigerant is introduced into the internal space (S) of the lower cylinder (420) through the refrigerant inlet passage (422), compressed by the lower roller (332), and then discharged through the lower discharge port.

[0211] Low pressure refrigerant can be supplied to the upper cylinder (410) and the lower cylinder (420) through the accumulator (5).

[0212] The intermediate plate (430) is installed between the upper cylinder (410) and the lower cylinder (420). The intermediate plate (430) may be formed in a flat plate shape. Accordingly, the lower cylinder (420), the intermediate plate (430), and the upper cylinder (410) may be laminated to form a compression member (40). The lower cylinder (420), the intermediate plate (430), and the upper cylinder (410) may be integrally joined by a plurality of bolts (93).

[0213] A main bearing plate (50) may be installed on the upper surface of the upper cylinder (410). The main bearing plate (50) may be fixed to the inner circumferential surface of the casing (10). Therefore, when the upper cylinder (410) is fixed to the main bearing plate (50), the upper cylinder (410) may be fixed to the casing (10).

[0214] The main bearing plate (50) rotatably supports the drive shaft (30) and can be formed to block the upper portion of the internal space (S) of the upper cylinder (410).

[0215] The main bearing plate (50) may include a through hole (52) and an upper trefoil (53). The inner surface of the through hole (52) may be formed as a main bearing surface. The upper trefoil (53) may be provided in an upper trefoil groove formed on the lower surface of the main bearing plate (50).

[0216] The upper trefoil (53) can be formed on the opposite side of the upper vane (441) of the upper cylinder (410) with respect to the drive shaft (30). The structure of the upper trefoil (53) of the main bearing plate (50) is the same as that of the upper trefoil (53) of the main bearing plate (50) according to the above-described embodiment, so a detailed description thereof is omitted.

[0217] The main bearing plate (50) may be provided with an upper hole communicating with the upper discharge port of the upper cylinder (410). Accordingly, the refrigerant discharged through the upper discharge port of the upper cylinder (410) may be discharged to the upper side of the main bearing plate (50) through the upper hole of the main bearing plate (50).

[0218] The main bearing plate (50) may include an upper discharge valve that opens and closes the upper hole. Accordingly, the upper hole of the main bearing plate (50) may be opened and closed by the upper discharge valve. When the refrigerant introduced into the upper cylinder (410) is compressed, the upper discharge valve opens, allowing the refrigerant to be discharged to the upper side of the main bearing plate (50).

[0219] An upper muffler (701) may be installed on the upper side of the main bearing plate (50). The upper muffler (701) is formed to reduce noise generated by refrigerant discharged through the upper hole of the main bearing plate (50).

[0220] A sub-bearing plate (60) may be installed on the lower surface of the lower cylinder (420). The sub-bearing plate (60) may be formed to rotatably support the lower portion of the driving shaft (30) and block the lower portion of the internal space (S) of the lower cylinder (420).

[0221] The sub-bearing plate (60) may include a through hole (62) and a lower trefoil (63). The inner surface of the through hole (62) may be formed as a sub-bearing surface. The lower trefoil (63) may be provided in a lower trefoil groove formed on the upper surface of the sub-bearing plate (60).

[0222] The lower trefoil (63) can be formed on the opposite side of the lower vane (442) of the lower cylinder (420) with respect to the drive shaft (30). The structure of the lower trefoil (63) of the sub-bearing plate (60) is the same as that of the lower trefoil (63) of the sub-bearing plate (60) according to the above-described embodiment, so a detailed description thereof is omitted.

[0223] The sub-bearing plate (60) may be provided with a lower hole communicating with the lower discharge port of the lower cylinder (420). Accordingly, the refrigerant discharged through the lower discharge port of the lower cylinder (420) may be discharged to the lower side of the sub-bearing plate (60) through the lower hole of the sub-bearing plate (60).

[0224] The sub-bearing plate (60) may include a lower discharge valve that opens and closes the lower hole. Accordingly, the lower hole of the sub-bearing plate (60) may be opened and closed by the lower discharge valve. When the refrigerant introduced into the lower cylinder (420) is compressed above a certain pressure, the lower discharge valve opens, allowing the refrigerant to be discharged to the lower side of the sub-bearing plate (60).

[0225] A lower muffler (702) may be installed on the lower side of the sub-bearing plate (60). The lower muffler (702) is formed to reduce noise generated by refrigerant discharged through the lower through hole of the sub-bearing plate (60).

[0226] Additionally, the sub-bearing plate (60) can be formed so that the refrigerant discharged through the lower hole is not discharged below the lower muffler (702).

[0227] The sub-bearing plate (60) may include a plurality of lower coolant holes provided along the circumferential direction. Coolant discharged from the lower holes of the sub-bearing plate (60) may flow to the upper side of the sub-bearing plate (60) through the plurality of lower coolant holes.

[0228] The refrigerant discharged from the lower hole of the sub-bearing plate (60) can move to the space formed by the main bearing plate (50) and the upper muffler (701) through the multiple lower refrigerant holes of the sub-bearing plate (60), the multiple refrigerant holes of the lower cylinder (420), the multiple refrigerant holes of the middle plate (430), the multiple refrigerant holes of the upper cylinder (410), and the multiple upper refrigerant holes of the main bearing plate (50).

[0229] The refrigerant in the space between the main bearing plate (50) and the upper muffler (701) can move to the upper side of the upper muffler (701) through multiple openings of the upper muffler (701).

[0230] As in the rotary compressor according to one embodiment of the present disclosure, by forming an upper trefoil on the main bearing plate and a lower trefoil on the sub-bearing plate, the bearing area supporting the rotation of the drive shaft is reduced, thereby reducing frictional loss due to the bearing. Accordingly, in the rotary compressor according to one embodiment of the present disclosure, the frictional loss of the bearing is reduced, thereby improving the performance of the compressor.

[0231] In addition, the rotary compressor according to one embodiment of the present disclosure can effectively support concentrated loads because the upper and lower trefoils formed in an arc shape only support a portion of the drive shaft. Therefore, the rotary compressor according to one embodiment of the present disclosure can have improved reliability compared to a rotary compressor according to the prior art having an annular trefoil structure.

[0232] While the present disclosure has been illustrated and described above with reference to various embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the scope of the present disclosure as defined by the appended claims and their equivalents.

Claims

1. Casing; A motor installed within the casing and including a drive shaft; and It includes a compression unit installed on the lower side of the motor and compressing the refrigerant according to the rotation of the drive shaft and discharging it into the casing; The above compression part, A cylinder into which refrigerant is sucked; A main bearing plate installed on the upper surface of the cylinder and including a main bearing surface that supports the driving shaft; An upper trefoil formed around the lower part of the main bearing surface on the lower surface of the main bearing plate; A sub-bearing plate installed on the lower surface of the cylinder and including a sub-bearing surface that supports the driving shaft; and A lower trefoil formed on the upper surface of the sub-bearing plate around the upper portion of the sub-bearing surface; A rotary compressor, wherein at least one of the upper trepan and the lower trepan is formed in an arc shape.

2. In paragraph 1, The above compression part, A roller installed inside the cylinder and rotating by the drive shaft to compress the refrigerant; and A rotary compressor further comprising a vane that is installed to be slidable relative to the cylinder and contacts the roller.

3. In paragraph 2, A rotary compressor, wherein the upper trefoil and the lower trefoil are formed in opposite directions with respect to the vane with respect to the drive shaft.

4. In paragraph 3, A rotary compressor in which the upper trepan and the lower trepan are formed in an arc shape of 180 to 300 degrees.

5. In paragraph 1, A rotary compressor in which the upper trepan and the lower trepan are formed in an asymmetrical shape.

6. In paragraph 1, On the lower surface of the above main bearing plate, an upper trefoil groove is formed around the upper trefoil, A rotary compressor, wherein a lower trefoil groove is formed around the lower trefoil on the upper surface of the sub-bearing plate.

7. In paragraph 1, A rotary compressor, wherein the cylinder of the compression section includes an upper cylinder and a lower cylinder.

8. In paragraph 1, A rotary compressor, wherein the main bearing surface and the sub-bearing surface are formed as journal bearings formed separately from the main bearing plate and the sub-bearing plate.

9. Casing; A motor installed within the casing and including a drive shaft; and It includes a compression unit installed on the lower side of the motor and compressing the refrigerant according to the rotation of the drive shaft and discharging it into the casing; The above compression part, middle plate; An upper cylinder installed on the upper surface of the above intermediate plate and into which refrigerant is sucked; A lower cylinder installed on the lower surface of the above intermediate plate and into which refrigerant is sucked; A main bearing plate installed on the upper surface of the upper cylinder and including a main bearing surface that supports the driving shaft; An upper trefoil formed around the lower part of the main bearing surface on the lower surface of the main bearing plate; A sub-bearing plate installed on the lower surface of the lower cylinder and including a sub-bearing surface; and A lower trefoil formed on the upper surface of the sub-bearing plate around the upper portion of the sub-bearing surface; A rotary compressor, wherein at least one of the upper trepan and the lower trepan is formed in an arc shape.

10. In paragraph 9, The above compression part, An upper roller installed inside the upper cylinder and rotating by the drive shaft to compress the refrigerant; An upper vane that is installed so as to be slidable relative to the upper cylinder and contacts the upper roller; A lower roller installed inside the lower cylinder and rotating by the drive shaft to compress the refrigerant; and A rotary compressor further comprising a lower vane that is in contact with the lower roller and is slidably installed relative to the lower cylinder.

11. In paragraph 10, A rotary compressor, wherein the upper trepan is formed in the opposite direction to the upper vane with respect to the drive shaft.

12. In paragraph 10, A rotary compressor, wherein the lower trepan is formed in the opposite direction to the lower vane with respect to the drive shaft.

13. In paragraph 11 or 12, A rotary compressor in which the upper trepan and the lower trepan are formed in an arc shape of 180 to 300 degrees.

14. In paragraph 9, A rotary compressor in which the upper trepan and the lower trepan are formed in an asymmetrical shape.

15. In home appliances that control temperature through heat exchange with the outside using a refrigerant, The above appliance includes a rotary compressor for compressing refrigerant, The above rotary compressor, casing; A motor installed within the casing and including a drive shaft; and It includes a compression unit installed on the lower side of the motor and compressing the refrigerant according to the rotation of the drive shaft and discharging it into the casing; The above compression part, A cylinder into which refrigerant is sucked; A main bearing plate installed on the upper surface of the cylinder and including a main bearing surface that supports the driving shaft; An upper trefoil formed around the lower part of the main bearing surface on the lower surface of the main bearing plate; A sub-bearing plate installed on the lower surface of the cylinder and including a sub-bearing surface that supports the driving shaft; and A lower trefoil formed on the upper surface of the sub-bearing plate around the upper portion of the sub-bearing surface; A home appliance, wherein at least one of the upper trepan and the lower trepan is formed in an arc shape.

Images