Rotary compressor and refrigeration device

Abstract

To restrain shaft deflection of a drive shaft by improving the shape of an oil passage.SOLUTION: A drive shaft (25) comprises a main shaft part (26), and an eccentric part (27). The drive shaft (25) is provided with an oil passage (30). The oil passage (30) comprises one or more oil holes (31) extending in an axial direction. When viewed from the axial direction of the drive shaft (25), a predetermined direction in a region surrounded by a virtual envelope (40) enveloping the oil holes (31) is defined as a first direction (Y), and a direction orthogonal to the first direction (Y) is defined as a second direction (X). When the oil passage (30) is viewed from the axial direction, a length in the first direction (Y) in the region surrounded by the virtual envelope (40) is longer than a length in the second direction (X).SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a rotary compressor and a refrigeration device.

Background Art

[0002] Patent Document 1 discloses a compressor including a compression mechanism having a rolling piston and a drive shaft (rotating shaft) that eccentrically rotates the rolling piston. An oil passage (central hole) extending in the axial direction is formed in the drive shaft. Refrigeration oil stored at the bottom of the sealed container is supplied to each sliding portion through the oil passage.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, there is a problem that the shaft deflection of the drive shaft increases due to the centrifugal force and gas load applied to the drive shaft as the compression mechanism rotates and drives.

[0005] Therefore, the inventor of the present application focused on the oil passage, which is a factor causing a decrease in the rigidity of the drive shaft, and considered improving the rigidity of the drive shaft by devising the shape of the oil passage.

[0006] An object of the present disclosure is to devise the shape of the oil passage to suppress the shaft deflection of the drive shaft.

Means for Solving the Problems

[0007] A first aspect of the present disclosure is a rotary compressor including a compression mechanism (50) and a drive shaft (25) that rotationally drives the compression mechanism (50). The drive shaft (25) has a main shaft portion (26) and an eccentric portion (27) that is eccentric from the axis (C1) of the main shaft portion (26) by a predetermined amount. An oil passage (30) having one or more oil holes (31) extending in the axial direction is provided in the drive shaft (25). When viewed from the axial direction of the drive shaft (25), a predetermined direction in a region surrounded by a virtual envelope (40) that envelopes the oil holes (31) is defined as a first direction (Y), and a direction orthogonal to the first direction (Y) is defined as a second direction (X). The oil passage (30) has a length in the first direction (Y) in a region surrounded by the virtual envelope (40) that is longer than the length in the second direction (X) when viewed from the axial direction.

[0008] In the first aspect, by forming the oil passage (30) such that the length in the first direction (Y) in the region surrounded by the virtual envelope (40) is longer than the length in the second direction (X), the rigidity of the drive shaft (25) can be improved and shaft deflection can be reduced.

[0009] Specifically, in order to suck up oil by the centrifugal pump action, the centrifugal pump needs to include, due to its structure, a small-diameter portion on the inlet side and a large-diameter portion on the outlet side having a larger hole diameter than the small-diameter portion.

[0010] In the case of a conventional rotary compressor, the small-diameter portion on the inlet side of the centrifugal pump corresponds to a suction port that opens in a tapered shape at the lower end of the centrifugal pump, and the large-diameter portion on the outlet side corresponds to a circular oil passage extending in the axial direction through the central portion of the drive shaft (25). Therefore, in a conventional rotary compressor, a relatively large-diameter circular oil passage having a length in the first direction (Y) as the diameter is provided in the central portion of the drive shaft (25), which may reduce the rigidity of the drive shaft (25).

[0011] On the other hand, by making the length in the second direction (X) of the oil passage (30) shorter than the length in the first direction (Y), compared to the case where a circular oil passage is provided in the central portion of the drive shaft (25), the cross-sectional area of the oil passage (30) becomes smaller, and the rigidity of the drive shaft (25) can be improved and shaft deflection can be reduced.

[0012] Further, by ensuring that the distance from the center of rotation of the drive shaft (25) to the inner wall surface at the location farthest radially in the oil passage (30) is equal to the radius of the circular oil passage, an equivalent centrifugal pump action can be obtained.

[0013] According to a second aspect of the present disclosure, in the rotary compressor of the first aspect, the first direction (Y) is a direction connecting the axis (C1) of the main shaft portion (26) and the axis (C2) of the eccentric portion (27) when viewed from the axial direction of the drive shaft (25).

[0014] In the second aspect, since the rigidity of the drive shaft (25) in the second direction (X) is higher than the rigidity in the first direction (Y), even when the maximum gas load during the rotational drive of the compression mechanism (50) is applied in the second direction (X) of the drive shaft (25), the shaft deflection of the drive shaft (25) can be suppressed.

[0015] According to a third aspect of the present disclosure, in the rotary compressor of the first or second aspect, the oil passage (30) is formed by a long hole-shaped oil hole (31) extending along the first direction (Y) when viewed from the axial direction.

[0016] In the third aspect, by forming the oil passage (30) with the long hole-shaped oil hole (31) extending along the first direction (Y) when viewed from the axial direction, the rigidity of the drive shaft (25) in the second direction (X) can be made higher than the rigidity in the first direction (Y).

[0017] According to a fourth aspect of the present disclosure, in the rotary compressor of the first or second aspect, the oil passage (30) is formed by a plurality of the oil holes (31) arranged along the first direction (Y) when viewed from the axial direction.

[0018] In the fourth aspect, by forming the oil passage (30) with the plurality of oil holes (31) arranged along the first direction (Y), the rigidity of the drive shaft (25) in the second direction (X) can be made higher than the rigidity in the first direction (Y).

[0019] The fifth aspect of the present disclosure is that in the rotary compressor of the fourth aspect, in the axial direction view, a part of the adjacent oil holes (31) overlap each other in the oil passage (30).

[0020] In the fifth aspect, when the length in the first direction (Y) of the region surrounded by the virtual envelope (40) is made constant, having a part of the adjacent oil holes (31) overlap each other will result in an increase in the number of oil holes (31) within the region surrounded by the virtual envelope (40) compared to an arrangement where the adjacent oil holes (31) are spaced apart from each other. This facilitates the machining of the oil passage (30) into a long hole shape.

[0021] The sixth aspect of the present disclosure is that in the rotary compressor according to any one of the first to fifth aspects, a motor (21) for rotating the drive shaft (25) is provided, and the compression mechanism (50) is disposed below the motor (21).

[0022] In the sixth aspect, for a rotary compressor in which the compression mechanism (50) is disposed below the motor (21), the shape of the oil passage (30) in which the length in the first direction (Y) of the region surrounded by the virtual envelope (40) is longer than the length in the second direction (X) can be applied.

[0023] The seventh aspect of the present disclosure is a refrigeration device including a rotary compressor (10) according to any one of the first to sixth aspects and a refrigerant circuit (1a) through which the refrigerant compressed by the rotary compressor (10) flows.

[0024] In the seventh aspect, a refrigeration device including a rotary compressor (10) and a refrigerant circuit (1a) can be provided.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Mode for Carrying Out the Invention

[0026] 《Embodiment 1》 As shown in FIG. 1, the rotary compressor (10) is provided in the refrigeration device (1). The refrigeration device (1) has a refrigerant circuit (1a) filled with refrigerant. The refrigerant circuit (1a) includes a rotary compressor (10), a radiator (3), a decompression mechanism (4), and an evaporator (5). The decompression mechanism (4) is, for example, an expansion valve. The refrigerant circuit (1a) performs a vapor compression refrigeration cycle.

[0027] The refrigeration device (1) is an air conditioner. The air conditioner may be a cooling-only machine, a heating-only machine, or an air conditioner that switches between cooling and heating. In this case, the air conditioner has a switching mechanism (for example, a four-way switching valve) for switching the circulation direction of the refrigerant. The refrigeration device (1) may be a water heater, a chiller unit, a cooling device for cooling the air inside a storage, etc. The cooling device cools the air inside a refrigerator, a freezer, a container, etc.

[0028] As shown in FIG. 2, the rotary compressor (10) includes a casing (11), a drive mechanism (20), and a compression mechanism (50).

[0029] The casing (11) is formed of a vertically long cylindrical sealed container. An intake pipe (16) penetrates and is fixed to the body portion of the casing (11). An accumulator (not shown) is connected to the intake pipe (16). A discharge pipe (17) penetrates and is fixed to the upper part of the casing (11).

[0030] An oil sump portion (18) is provided at the bottom of the casing (11). Oil is stored in the oil sump portion (18). The oil is used to lubricate the sliding portions of the compression mechanism (50) and the drive shaft (25).

[0031] 〈Drive mechanism〉 The drive mechanism (20) is housed inside the casing (11). The drive mechanism (20) includes a motor (21) and a drive shaft (25). The motor (21) is disposed above the compression mechanism (50). The motor (21) includes a stator (22) and a rotor (23).

[0032] The stator (22) is fixed to the inner peripheral surface of the casing (11). The rotor (23) penetrates the inside of the stator (22) in the vertical direction. Inside the axis of the rotor (23), a drive shaft (25) is fixed. When the motor (21) is energized, the drive shaft (25) is rotationally driven together with the rotor (23).

[0033] The drive shaft (25) is arranged on the axis of the casing (11). An oil passage (30) is formed inside the drive shaft (25). A centrifugal oil pump (28) is provided at the lower end of the drive shaft (25). An inlet (28a) is provided below the oil pump (28). The oil pump (28) conveys the oil stored in the oil reservoir (18). The conveyed oil is supplied to the compression mechanism (50) and the sliding portion of the drive shaft (25) through the oil passage (30) of the drive shaft (25).

[0034] The drive shaft (25) has a main shaft portion (26) and an eccentric portion (27). The upper part of the main shaft portion (26) is fixed to the rotor (23) of the motor (21). The axis of the eccentric portion (27) is eccentric by a predetermined amount from the axis of the main shaft portion (26).

[0035] The upper part of the main shaft portion (26) above the eccentric portion (27) is rotatably supported by a front head (52) described later. The lower part of the main shaft portion (26) below the eccentric portion (27) is rotatably supported by a rear head (53) described later.

[0036] 〈Compression mechanism〉 The compression mechanism (50) is housed inside the casing (11). The compression mechanism (50) is arranged below the motor (21). The compression mechanism (50) has a cylinder (51), a front head (52), a rear head (53), and a piston (54).

[0037] The cylinder (51) is formed of a flat substantially annular member. A circular compression chamber (55) is formed at the center of the cylinder (51). An intake passage (56) extending in the radial direction is formed in the cylinder (51). The downstream end of the intake passage (56) communicates with the compression chamber (55). An intake pipe (16) is connected to the upstream end of the intake passage (56).

[0038] The front head (52) is disposed above the cylinder (51). The front head (52) is arranged to cover the internal space of the cylinder (51) from above. The front head (52) rotatably supports the main shaft portion (26) of the drive shaft (25). A discharge passage (not shown) penetrating in the axial direction is formed in the front head (52).

[0039] The rear head (53) is disposed below the cylinder (51). The rear head (53) is arranged to cover the internal space of the cylinder (51) from below. The rear head (53) rotatably supports the main shaft portion (26) of the drive shaft (25).

[0040] As shown also in FIG. 3, the piston (54) is housed inside the cylinder (51). The blade (57) is integrally formed with the piston (54). The compression chamber (55) is partitioned by the cylinder (51) and the piston (54). The piston (54) is formed in a perfect circular ring shape. The eccentric portion (27) of the drive shaft (25) is fitted inside the piston (54).

[0041] The inside of the compression chamber (55) is partitioned by the blade (57) into a low-pressure chamber (55a) and a high-pressure chamber (55b) (see FIG. 11). The blade (57) is swingably supported by a pair of bushes (58).

[0042] As the piston (54) eccentrically rotates within the cylinder (51) along with the rotational drive of the drive shaft (25), when the volume of the low-pressure chamber (55a) gradually increases along with the eccentric rotation of the piston (54), the refrigerant flowing through the intake pipe (16) is inhaled from the intake passage (56) into the low-pressure chamber (55a).

[0043] Next, when the low-pressure chamber (55a) is blocked from the suction passage (56), the blocked space forms the high-pressure chamber (55b). As the volume of the high-pressure chamber (55b) gradually decreases, the internal pressure of the high-pressure chamber (55b) rises. When the internal pressure of the high-pressure chamber (55b) exceeds a predetermined pressure, the refrigerant in the high-pressure chamber (55b) flows out to the outside of the compression mechanism (50) through the discharge passage (59). This high-pressure refrigerant flows upward through the internal space of the casing (11) and passes through the core cut (not shown) of the motor (21), etc. The high-pressure refrigerant flowing out above the motor (21) is sent from the discharge pipe (17) to the refrigerant circuit (1a).

[0044] 〈Regarding the oil passage〉 By the way, there is a problem that the shaft deflection of the drive shaft (25) increases due to the centrifugal force and gas load applied to the drive shaft (25) as the compression mechanism (50) rotates and drives.

[0045] Therefore, the inventor of the present application focused on the oil passage (30) which is a factor for the reduction of the rigidity of the drive shaft (25), and considered improving the rigidity of the drive shaft (25) by devising the shape of the oil passage (30).

[0046] As shown in FIG. 2, an oil passage (30) is provided in the drive shaft (25). The oil passage (30) has an oil hole (31), a lower end hole (35), and a lateral hole (36).

[0047] The lower end hole (35) opens at the lower end of the main shaft portion (26) of the drive shaft (25). A fuel supply pump (28) is attached to the lower end hole (35). The oil hole (31) communicates with the lower end hole (35) and extends upward. The lateral hole (36) communicates with the oil hole (31) and extends horizontally. The lateral hole (36) opens at positions where oil can be supplied to the sliding portions of the compression mechanism (50) and the drive shaft (25), respectively.

[0048] In the example shown in FIG. 2, the lateral holes (36) open to the sliding surfaces of the front head (52), the rear head (53), and the piston (54). A gas vent hole (37) is formed at a position above the front head (52) on the drive shaft (25). The gas vent hole (37) discharges the gas contained in the oil passing through the oil passage (30).

[0049] The oil flowing through the oil hole (31) is discharged to the outside of the drive shaft (25) through the lateral holes (36) by the centrifugal force accompanying the rotation of the drive shaft (25), and is supplied to the sliding portions of the compression mechanism (50) and the drive shaft (25).

[0050] As shown in FIG. 4, let the axis of the main shaft portion (26) be the axis (C1) and the axis of the eccentric portion (27) be the axis (C2). When viewed from the axial direction of the drive shaft (25), a predetermined direction in the region surrounded by the virtual envelope (40) that envelopes the oil hole (31) is defined as the first direction (Y), and a direction orthogonal to the first direction (Y) is defined as the second direction (X).

[0051] In the example shown in FIG. 4, when viewed from the axial direction of the drive shaft (25), the direction connecting the axis (C1) of the main shaft portion (26) and the axis (C2) of the eccentric portion (27) is defined as the first direction (Y), and a direction orthogonal to the first direction (Y) is defined as the second direction (X). However, the present invention is not limited to this form.

[0052] The oil passage (30) is formed by an elongated oil hole (31) extending along the first direction (Y) when viewed from the axial direction. Here, let the length of the oil hole (31) in the second direction (X) be x and the first direction (Y) of the oil hole (31) be y. The elongated oil hole (31) can be represented as the locus when a circle with a diameter of x is continuously moved in the first direction (Y). Here, a curve that is tangent to all the circles is called an envelope. In the example shown in FIG. 4, when viewed from the axial direction, the virtual envelope (40) that envelopes the oil hole (31) is shown as a virtual line. The virtual envelope (40) is represented as an elongated curve extending along the inner peripheral edge of the oil hole (31).

[0053] Here, in the axial direction view, the length y in the first direction (Y) of the oil passage (30) in the region surrounded by the virtual envelope line (40) enclosing the oil hole (31) is longer than the length x in the second direction (X). Thereby, the rigidity of the drive shaft (25) can be improved and the shaft deflection can be reduced.

[0054] Specifically, when a circular oil passage with a larger hole diameter than the suction port (28a) and having a length in the first direction (Y) as the diameter is provided at the center of the drive shaft (25) to suck up oil by the centrifugal pump action, a relatively large cavity (refer to the region surrounded by the virtual line in Fig. 5) will be provided at the center of the drive shaft (25), and there is a risk of a decrease in the rigidity of the drive shaft (25).

[0055] In contrast, by making the length of the oil passage (30) in the second direction (X) shorter than the length in the first direction (Y), compared with the case of providing a circular oil passage at the center of the drive shaft (25), the passage area of the oil passage (30) becomes smaller, and the rigidity of the drive shaft (25) can be improved and the shaft deflection can be reduced.

[0056] Also, by ensuring that the distance from the center of rotation of the drive shaft (25) to the inner wall surface at the location farthest in the radial direction in the oil passage (30) is equal to the radius of the circular oil passage, an equivalent centrifugal pump action can be obtained (refer to Fig. 5).

[0057] Moreover, by forming the oil passage (30) such that the length in the first direction (Y) in the region surrounded by the virtual envelope line (40) is longer than the length in the second direction (X), the rigidity of the drive shaft (25) in the second direction (X) can be made higher than the rigidity in the first direction (Y).

[0058] Hereinafter, the relationship between the shape of the oil hole (31) and the bending rigidity of the drive shaft (25) will be described with reference to Figs. 6 and 7. In Figs. 6 and 7, only the main shaft portion (26) of the drive shaft (25) is shown, and the description of the eccentric portion (27) is omitted. Also, for easier explanation, the oil hole (31) will be described as a rectangular shape extending in the first direction (Y) that approximates the elongated hole shape rather than the elongated hole shape extending in the first direction (Y).

[0059] As shown in Fig. 6, let the diameter of the main shaft portion (26) be D. When a load is applied to the main shaft portion (26) of the drive shaft (25) from the first direction (Y), the second moment of area Iy is calculated by the following formula (1).

[0060] Iy = (π·D 4 / 64) - (x·y 3 / 12) ···(1) On the other hand, as shown in Fig. 7, when a load is applied to the main shaft portion (26) of the drive shaft (25) from the second direction (X), the second moment of area Ix is calculated by the following formula (2).

[0061] Ix = (π·D 4 / 64) - (y·x 3 / 12) ···(2) Here, since x < y, the value of Iy including "y" will decrease more significantly than the value of Ix including "y". That is, since Ix > Iy, the bending stiffness of the drive shaft (25) in the second direction (X) is higher than that in the first direction (Y). 3 Next, the relationship between the rotation angle of the drive shaft (25) and the load applied to the drive shaft (25) will be described using the graph diagrams of Figs. 8 to 10. As shown in Fig. 3, the posture in which the eccentric portion (27) of the drive shaft (25) faces upward in Fig. 3 is defined as the top dead center 0°.

[0062]

[0063] Fig. 8 is a graph diagram showing the relationship between the angle from the top dead center and the magnitude of the force applied to the drive shaft (25). In the case of Fig. 8, it can be seen that the maximum gas load during the rotational drive of the compression mechanism (50) is applied at the position where the drive shaft (25) rotates 227° from the top dead center 0°.

[0064] ​FIG. 9 is a graph showing the relationship between the angle from top dead center and the direction of the force applied to the drive shaft (25). As shown in FIG. 9, at the position of 227°, which is the angle at which the maximum gas load is applied during the rotational drive of the compression mechanism (50), it can be seen that the direction of the gas load applied to the drive shaft (25) is 119.18° (≈119°).

[0065] FIG. 10 is a graph showing the relationship between the angle from top dead center and the direction of the gas load applied to the drive shaft (25) with the eccentric direction of the eccentric part (27) as the reference 0°. As shown in FIG. 10, at the position of 227°, which is the rotational angle at which the maximum gas load is applied during the rotational drive of the compression mechanism (50), it can be seen that the direction of the gas load applied to the drive shaft (25) with the eccentric direction of the eccentric part (27) as the reference 0° is -107.82° (≈ -108°).

[0066] FIG. 11 is a diagram for explaining the angle at which the maximum gas load is applied to the drive shaft (25). In the case of FIG. 11, at the position where the drive shaft (25) rotates 227° from top dead center 0°, the maximum gas load during the rotational drive of the compression mechanism (50) is applied in the direction rotated 108° counterclockwise from the first direction (Y) connecting the axis (C1) of the main shaft part (26) and the axis (C2) of the eccentric part (27). In FIG. 11, the load direction is indicated by a white arrow line.

[0067] Here, the direction of the maximum gas load during the rotational drive of the compression mechanism (50) varies within a range of, for example, 80° to 110° depending on the compression conditions and the like. Since the second direction (X) is a direction orthogonal to the first direction (Y), that is, a direction rotated 90° with respect to the first direction (Y), it is included in the range of the maximum gas load direction of 80° to 110°.

[0068] As described above, the rigidity of the drive shaft (25) in the second direction (X) is higher than the rigidity in the first direction (Y). Therefore, even when the maximum gas load during the rotational drive of the compression mechanism (50) is applied to the second direction (X) of the drive shaft (25), the shaft deflection of the drive shaft (25) can be suppressed.

[0069] In addition, in order to further increase the rigidity of the drive shaft (25) with respect to the maximum gas load during the rotational drive of the compression mechanism (50), the shape of the oil passage (30) may be set so that the angle between the maximum gas load direction (108°) and the second direction (X) coincides with each other.

[0070] Further, it is preferable to set the length y in the first direction (Y) of the oil hole (31) such that the positions of both ends in the first direction (Y) of the virtual envelope (40) are located radially outside the suction port (28a) of the oil supply pump (28) when viewed from the axial direction. In this way, oil supply by the centrifugal pump due to the centrifugal force accompanying the rotation of the drive shaft (25) can be performed smoothly.

[0071] - Effects of Embodiment 1 - According to the features of the present embodiment, by forming the oil passage (30) such that the length in the first direction (Y) in the region surrounded by the virtual envelope (40) is longer than the length in the second direction (X), the rigidity of the drive shaft (25) can be improved.

[0072] Thereby, even when a centrifugal force is applied to the drive shaft (25) due to the eccentric weights of the eccentric portion (27) and the piston (54) as the drive shaft (25) rotates, the shaft deflection of the drive shaft (25) can be reduced.

[0073] In addition, by securing the distance from the rotation center of the drive shaft (25) in the oil passage (30) to the inner wall surface at the location farthest radially away to be equivalent to the radius of the circular oil passage, an equivalent centrifugal pump action can be obtained.

[0074] And by suppressing such shaft deflection of the drive shaft (25), the generation of noise due to the runout of the drive shaft (25) can be suppressed.

[0075] According to the features of the present embodiment, since the rigidity of the drive shaft (25) in the second direction (X) is higher than the rigidity in the first direction (Y), even when the maximum gas load during the rotational drive of the compression mechanism (50) is applied in the second direction (X) of the drive shaft (25), the shaft deflection of the drive shaft (25) can be suppressed.

[0076] According to the features of this embodiment, by forming the oil passage (30) with an elongated hole-shaped oil hole (31) extending along the first direction (Y) when viewed from the axial direction, the rigidity of the drive shaft (25) in the second direction (X) can be made higher than the rigidity in the first direction (Y).

[0077] According to the features of this embodiment, for a rotary compressor in which the compression mechanism (50) is arranged below the motor (21), the shape of the oil passage (30) in which the length in the first direction (Y) in the region surrounded by the virtual envelope (40) is longer than the length in the second direction (X) can be applied.

[0078] According to the features of this embodiment, a refrigeration device including a rotary compressor (10) and a refrigerant circuit (1a) can be provided.

[0079] 《Embodiment 2》 Hereinafter, the same parts as those in the above Embodiment 1 are denoted by the same reference numerals, and only the differences will be described.

[0080] As shown in FIG. 12, the oil hole (31) of the oil passage (30) is formed of a rectangular hole extending along the first direction (Y) when viewed from the axial direction. In the example shown in FIG. 12, when viewed from the axial direction, a virtual envelope (40) that envelopes the oil hole (31) is shown by a virtual line. The virtual envelope (40) is represented as a rectangular line extending along the inner peripheral edge of the oil hole (31).

[0081] Here, in the oil passage (30), when viewed from the axial direction, the length y in the first direction (Y) in the region surrounded by the virtual envelope (40) that envelopes the oil hole (31) is longer than the length x in the second direction (X).

[0082] -Effect of Embodiment 2- According to the features of this embodiment, the rigidity of the drive shaft (25) in the second direction (X) can be made higher than the rigidity in the first direction (Y).

[0083] 《Embodiment 3》 As shown in Fig. 13, the oil passage (30) is formed by a plurality of oil holes (31) arranged along the first direction (Y) when viewed axially. All of the plurality of oil holes (31) are formed as holes having the same inner diameter. In the example shown in Fig. 13, four oil holes (31) are provided along the first direction (Y), but this is merely an example and is not intended to be limiting. In the example shown in Fig. 13, a virtual envelope (40) that envelopes the plurality of oil holes (31) is shown as a virtual line when viewed axially. The virtual envelope (40) is represented as an elongated hole-shaped curve extending along the first direction (Y).

[0084] Here, in the oil passage (30), when viewed axially, the length y in the first direction (Y) in the region surrounded by the virtual envelope (40) that envelopes the plurality of oil holes (31) is longer than the length x in the second direction (X).

[0085] In this embodiment, the plurality of oil holes (31) are arranged to be symmetric with respect to the axis (C1) of the main shaft portion (26), but the present invention is not limited to this form and an asymmetric arrangement may also be possible.

[0086] Further, it is preferable to set the position of the oil holes (31) in the first direction (Y) such that the positions of both ends in the first direction (Y) of the virtual envelope (40) are located radially outside the suction port (28a) of the oil supply pump (28) when viewed axially. By doing so, oil supply by the centrifugal pump due to the centrifugal force associated with the rotation of the drive shaft (25) can be performed smoothly.

[0087] Note that the two oil holes (31) arranged between the oil holes (31) at both ends in the first direction (Y) are used to discharge the gas contained in the oil from the gas vent hole (37).

[0088] - Effects of Embodiment 3 - According to the features of the present embodiment, by forming the oil passage (30) with a plurality of oil holes (31) arranged along the first direction (Y), the rigidity of the drive shaft (25) in the second direction (X) can be made higher than the rigidity in the first direction (Y).

[0089] 《Embodiment 4》 As shown in FIG. 14, the oil passage (30) is formed by a plurality of oil holes (31) arranged along the first direction (Y) when viewed axially. The plurality of oil holes (31) include holes with different inner diameters. In the example shown in FIG. 14, three oil holes (31) are provided at intervals in the first direction (Y), but this is merely an example and is not limited thereto. Among the three oil holes (31), the inner diameter of the oil hole (31) located at the central portion in the first direction (Y) is larger than the inner diameters of the oil holes (31) located at both ends in the first direction (Y).

[0090] In the example shown in FIG. 14, when viewed axially, a virtual envelope (40) enclosing the plurality of oil holes (31) is indicated by a virtual line. The virtual envelope (40) is represented as a curve such that the length x in the second direction (X) is the largest at the central portion in the first direction (Y) and gradually decreases as it goes toward both ends in the second direction (X).

[0091] Here, in the oil passage (30), when viewed axially, the length y in the first direction (Y) in the region surrounded by the virtual envelope (40) enclosing the plurality of oil holes (31) is longer than the length x in the second direction (X). Here, the length x at the central portion in the second direction (X), which is the position where the length x in the second direction (X) is the largest, is compared with the length y in the first direction (Y).

[0092] Note that the oil holes (31) arranged between the oil holes (31) at both ends in the first direction (Y) are used to discharge the gas contained in the oil from the gas vent hole (37).

[0093] - Effects of Embodiment 4 - According to the features of the present embodiment, by forming the oil passage (30) with a plurality of oil holes (31) arranged along the first direction (Y), the rigidity of the drive shaft (25) in the second direction (X) can be made higher than the rigidity in the first direction (Y).

[0094] 《Embodiment 5》 As shown in FIG. 15, the oil passage (30) is formed by a plurality of oil holes (31) arranged along the first direction (Y) when viewed in the axial direction. The plurality of oil holes (31) are all formed of holes having the same inner diameter. The oil passage (30) has a part of adjacent oil holes (31) overlapping when viewed in the axial direction.

[0095] In the example shown in FIG. 15, a virtual envelope line (40) enclosing the plurality of oil holes (31) is shown by a virtual line when viewed in the axial direction. The virtual envelope line (40) is represented as an elongated hole-shaped curve extending along the first direction (Y).

[0096] Here, in the oil passage (30), when viewed in the axial direction, the length y in the first direction (Y) in the region surrounded by the virtual envelope line (40) enclosing the plurality of oil holes (31) is longer than the length x in the second direction (X).

[0097] -Effect of Embodiment 5- According to the features of the present embodiment, when the length in the first direction (Y) of the region surrounded by the virtual envelope line (40) is constant, overlapping a part of adjacent oil holes (31) increases the number of oil holes (31) in the region surrounded by the virtual envelope line (40) compared to an arrangement in which adjacent oil holes (31) are spaced apart from each other. As a result, it becomes easier to process the oil passage (30) into an elongated hole shape.

[0098] 《Embodiment 6》 As shown in FIG. 16, the rotary compressor (10) includes a casing (11), a drive mechanism (20), and a compression mechanism (50).

[0099] The drive mechanism (20) includes a motor (21) and a drive shaft (25). The drive shaft (25) has a main shaft portion (26) and two eccentric portions (27). The axis of the eccentric portion (27) is eccentric from the axis of the main shaft portion (26) by a predetermined amount. The two eccentric portions (27) are eccentric in directions different from each other by 180° (see also FIG. 17).

[0100] The compression mechanism (50) includes two cylinders (51), a front head (52), a rear head (53), two pistons (54), and a middle plate (60). The middle plate (60) is sandwiched between the two cylinders (51).

[0101] As shown in FIG. 17, let the axis of the main shaft portion (26) be the axis (C1), and the axes of the two eccentric portions (27) be the axes (C2), respectively. When viewed from the axial direction of the drive shaft (25), a predetermined direction in the region surrounded by the virtual envelope line (40) that envelopes the oil hole (31) is defined as the first direction (Y), and a direction orthogonal to the first direction (Y) is defined as the second direction (X).

[0102] In the example shown in FIG. 17, when viewed from the axial direction of the drive shaft (25), the direction connecting the axis (C1) of the main shaft portion (26) and the axis (C2) of the eccentric portion (27) is defined as the first direction (Y), and a direction orthogonal to the first direction (Y) is defined as the second direction (X). However, the present invention is not limited to this form.

[0103] The oil passage (30) is formed by a long-hole-shaped oil hole (31) that extends along the first direction (Y) when viewed from the axial direction. In the example shown in FIG. 17, when viewed from the axial direction, the virtual envelope line (40) that envelopes the oil hole (31) is shown as a virtual line. The virtual envelope line (40) is represented as a long-hole-shaped curve that extends along the inner peripheral edge of the oil hole (31).

[0104] Here, in the oil passage (30), when viewed from the axial direction, the length y in the first direction (Y) in the region surrounded by the virtual envelope line (40) that envelopes the oil hole (31) is longer than the length x in the second direction (X).

[0105] Note that the oil passage (30) may be configured by a plurality of oil holes (31) arranged along the first direction (Y) when viewed from the axial direction, similar to the case of the third embodiment described above. Also, the oil passage (30) may be configured such that a part of adjacent oil holes (31) overlaps when viewed from the axial direction, similar to the case of the fifth embodiment described above.

[0106] - Effects of Embodiment 6 - According to the features of this embodiment, the rigidity of the drive shaft (25) in the second direction (X) can be made higher than the rigidity in the first direction (Y).

[0107] 《Other Embodiments》 The above embodiment may have the following configuration.

[0108] In this embodiment, the oil hole (31) of the oil passage (30) is formed as a long hole extending along the first direction (Y) when viewed from the axial direction, but it is not limited to this form. For example, the oil hole (31) may be formed as an elliptical hole extending along the first direction (Y) when viewed from the axial direction.

[0109] In this embodiment, an oil supply pump (28) is attached to the lower end of the drive shaft (25) to suck up oil from the oil supply pump (28), but it is not limited to this form. For example, the lower end of the drive shaft (25) may be extended to a position where it is immersed in the oil reservoir portion (18), and the lower end hole (35) of the oil passage (30) that opens at the lower end of the drive shaft (25) may be covered with an end plate (not shown) having an inlet hole at the center. Thereby, oil can be sucked up from the inlet hole of the end plate toward the oil passage (30) of the drive shaft (25).

[0110] Also, any one of the plurality of oil holes (31) may be used as an oil supply path to the sliding portion between the drive shaft (25), the front head (52), and the rear head (53), while the other oil holes (31) may be used as an oil supply path to the cylinder (51), etc., and they may be used separately according to the application.

[0111] As described above, the embodiments have been explained, but it will be understood that various changes in form and details are possible without departing from the spirit and scope of the claims. Also, the elements according to the above embodiments, modifications, and other embodiments may be combined or replaced as appropriate. Also, the descriptions such as "first", "second", "third",... in the specification and claims are used to distinguish the phrases to which these descriptions are given, and neither the number nor the order of these phrases is limited.

Industrial Applicability

[0112] As described above, the present disclosure is useful for rotary compressors and refrigeration devices.

Explanation of Signs

[0113] 1 Refrigeration device 1a Refrigerant circuit 10 Rotary compressor 21 Motor 25 Drive shaft 26 Main shaft portion 27 Eccentric portion 30 Oil passage 31 Oil hole 40 Virtual envelope 50 Compression mechanism C1 Axis center C2 Axis center X Second direction Y First direction

Claims

1. A rotary compressor comprising: a compression mechanism (50); and a drive shaft (25) that rotationally drives the compression mechanism (50), The drive shaft (25) has a main shaft portion (26) and an eccentric portion (27) that is eccentric from an axis (C1) of the main shaft portion (26) by a predetermined amount, The drive shaft (25) is provided with an oil passage (30) having one or more oil holes (31) extending in the axial direction, When viewed from the axial direction of the drive shaft (25), a predetermined direction in a region surrounded by a virtual envelope (40) enveloping the oil hole (31) is defined as a first direction (Y), and a direction perpendicular to the first direction (Y) is defined as a second direction (X), When viewed in the axial direction, the length of the oil passage (30) in the first direction (Y) in a region surrounded by the imaginary envelope (40) is longer than the length of the oil passage (30) in the second direction (X), The oil passage (30) is formed of an elongated oil hole (31) extending along the first direction (Y) when viewed in the axial direction. Rotary compressor.

2. A rotary compressor comprising: a compression mechanism (50); and a drive shaft (25) that rotationally drives the compression mechanism (50), The drive shaft (25) has a main shaft portion (26) and an eccentric portion (27) that is eccentric from an axis (C1) of the main shaft portion (26) by a predetermined amount, The drive shaft (25) is provided with an oil passage (30) having one or more oil holes (31) extending in the axial direction, When viewed from the axial direction of the drive shaft (25), a predetermined direction in a region surrounded by a virtual envelope (40) enveloping the oil hole (31) is defined as a first direction (Y), and a direction perpendicular to the first direction (Y) is defined as a second direction (X), When viewed in the axial direction, the length of the oil passage (30) in the first direction (Y) in a region surrounded by the imaginary envelope (40) is longer than the length of the oil passage (30) in the second direction (X), The oil passage (30) is formed of a plurality of the oil holes (31) arranged along the first direction (Y) when viewed in the axial direction, The oil passage (30) is arranged such that adjacent oil holes (31) partially overlap each other when viewed in the axial direction. Rotary compressor.

3. The rotary compressor according to claim 1 or 2, The first direction (Y) is a direction connecting the axis (C1) of the main shaft portion (26) and the axis (C2) of the eccentric portion (27) when viewed in the axial direction of the drive shaft (25). Rotary compressor.

4. In the rotary compressor of claim 1 or 2, a motor (21) for rotating the drive shaft (25), The compression mechanism (50) is disposed below the motor (21). Rotary compressor.

5. A rotary compressor (10) according to claim 1 or 2; a refrigerant circuit (1a) through which the refrigerant compressed by the rotary compressor (10) flows. Refrigeration equipment.

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