Rotary compressor

Abstract

Invention details;

Description

Rotary Compressor

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

[0002] Conventionally, compressors used in air conditioners and the like are known. Patent Document 1 discloses a hermetically sealed, vertical compressor. In this compressor, a compression mechanism is housed in a casing, and a coupling pipe is connected to the casing.

[0003] An accumulator is connected upstream of the compressor. The accumulator has a sealed container and an outlet pipe through which the refrigerant flows out of the sealed container. The outlet pipe is connected to the compression mechanism via a suction pipe. The suction pipe is disposed inside the coupling pipe and connects the sealed container of the accumulator to the compression mechanism.

[0004] Japanese Patent Application Laid-Open No. 2020-70748

[0005] In the compressor of Patent Document 1, vibrations from the compression mechanism propagate from the suction pipe to the coupling pipe and then to the outlet pipe, which can cause the sealed container of the accumulator to vibrate and generate noise.

[0006] An object of the present disclosure is to suppress vibrations transmitted from the compression mechanism to the accumulator.

[0007] A first aspect of the present disclosure provides an accumulator (45) comprising: a casing (11); a compression mechanism (50) accommodated in the casing (11) and having an intake port (56); a joint pipe (43) fixed to the casing (11); an intake pipe (40) disposed inside the joint pipe (43) and communicating with the intake port (56) of the compression mechanism (50); and an accumulator (45) having an outlet pipe (48) connected to an inlet end of the intake pipe (40), wherein the intake pipe (40) has: a large diameter portion (41) formed on an inlet side of the intake pipe (40) and fixed to an inner peripheral surface of the joint pipe (43); and a small diameter portion (42) formed on an outlet side of the intake pipe (40) and having an outer diameter smaller than that of the large diameter portion (41), the joint pipe (43) being made of an iron-based material, A gap (S1) is formed between the outer peripheral surface of the small diameter portion (42) of the suction pipe (40) and the inner peripheral surface of the joint pipe (43).

[0008] In the first aspect, vibrations generated in the compression mechanism (50) are transmitted in this order through the suction pipe (40), the joint pipe (43), and the outlet pipe (48). Because a gap (S1) is formed between the outer circumferential surface of the small-diameter portion (42) of the suction pipe (40) and the inner circumferential surface of the joint pipe (43), even when vibrations from the compression mechanism (50) are transmitted to the suction pipe (40), the small-diameter portion (42) vibrates without contacting the inner circumferential surface of the joint pipe (43). Therefore, vibrations transmitted from the compression mechanism (50) are damped by the small-diameter portion (42). In addition, because the joint pipe (43) is made of an iron-based material, the joint pipe (43) has high rigidity. Therefore, vibrations can be insulated at the connection between the large-diameter portion (41) of the suction pipe (40) and the joint pipe (43). This suppresses vibrations transmitted from the compression mechanism (50) to the accumulator (45).

[0009] A second aspect of the present disclosure is the rotary compressor of the first aspect, wherein an inlet end (E) of the small diameter portion (42) is located closer to the accumulator (45) than an axial center portion (C) of the coupling pipe (43).

[0010] In the second aspect, the inlet end (E) of the small diameter portion (42) of the suction pipe (40) is located closer to the accumulator (45) than the axial center (C) of the joint pipe (43), thereby making it possible to lengthen the small diameter portion (42), thereby further attenuating vibrations transmitted from the compression mechanism (50) to the suction pipe (40).

[0011] A third aspect of the present disclosure is the rotary compressor of the first or second aspect, wherein the joint pipe (43) has a welded portion (43a) welded to the casing (11).

[0012] In the third aspect, the rigidity of the welded portion (43a) can be increased by welding the joint pipe (43) to the casing (11), thereby enabling the joint pipe (43) to further insulate the vibrations transmitted from the compression mechanism (50) to the suction pipe (40).

[0013] A fourth aspect of the present disclosure is the rotary compressor of the third aspect, wherein the joint pipe (43) has a thickness greater than a thickness of the casing (11).

[0014] In the fourth aspect, the thickness of the joint pipe (43) is greater than the thickness of the casing (11), and therefore deformation of the joint pipe (43) due to heat when the joint pipe (43) and the casing (11) are welded together can be suppressed.

[0015] A fifth aspect of the present disclosure is the rotary compressor according to any one of the first to fourth aspects, wherein the outlet pipe (48) is made of an iron-based material.

[0016] In the fifth aspect, the outlet pipe (48) is made of an iron-based material, thereby increasing the rigidity of the outlet pipe (48), thereby enabling the outlet pipe (48) to further insulate the vibrations transmitted from the compression mechanism (50) to the suction pipe (40).

[0017] A sixth aspect of the present disclosure is the rotary compressor (10) of any one of the first to fifth aspects, wherein the axial length L2 of the small diameter portion (42) of the suction pipe (40) is 58% or more of the total axial length L1 of the suction pipe (40).

[0018] In the sixth aspect, the axial length of the small diameter portion (42) is relatively long, so that vibrations from the compression mechanism (50) are easily damped by the small diameter portion (42) of the suction pipe (40).

[0019] Fig. 1 is a longitudinal cross-sectional view showing the configuration of a rotary compressor of an embodiment. Fig. 2 is a longitudinal cross-sectional view showing an enlarged view of the periphery of a suction pipe. Fig. 3 is a graph showing the relationship between the rotation speed of the rotary compressor and sound intensity. Fig. 4 is a graph showing the relationship between L2 / L1 and the peak value of acceleration of the accumulator. Fig. 5 is a longitudinal cross-sectional view showing the configuration of a rotary compressor of a second modified example.

[0020] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the following embodiments are essentially preferred examples and are not intended to limit the scope of the present invention, its applications, or its uses.

[0021] <<Embodiment>> An embodiment will be described.

[0022] As shown in Fig. 1, the compressor (10) of this embodiment is a hermetic rotary compressor. The compressor (10) is connected to a refrigerant circuit (not shown) filled with refrigerant. The refrigerant circuit operates in a vapor compression refrigeration cycle. Specifically, in the refrigerant circuit, refrigerant compressed by the compressor (10) is condensed in a condenser, reduced in pressure by an expansion valve, evaporated in an evaporator, and then sucked into the compressor (10).

[0023] —Configuration of Compressor— The compressor (10) includes a casing (11), a compression mechanism (50), and a drive mechanism (20). The compression mechanism (50) and the drive mechanism (20) are housed inside the casing (11). The drive mechanism (20) drives the compression mechanism (50).

[0024] <Casing> The casing (11) is a vertically long, cylindrical, sealed container. The casing (11) has a body (12), a lower head plate (13), and an upper head plate (14). The body (12) is configured in a cylindrical shape extending in the vertical direction (axial direction). Both ends of the body (12) in the vertical direction are open. The lower head plate (13) is fixed to the lower end of the body (12). The upper head plate (14) is fixed to the upper end of the body (12).

[0025] A suction pipe (40) is fixed to pass through the lower part of the body (12). A discharge pipe (16) is fixed to pass through the upper head (14). The detailed configuration of the suction pipe (40) and its surroundings will be described later.

[0026] A reservoir (18) is formed at the bottom of the casing (11). The reservoir (18) stores oil (refrigeration oil) for lubricating the sliding parts of the compression mechanism (50) and a drive shaft (30) described below. The reservoir (18) is defined by the lower head (13) and the inner wall of the lower part of the body (12).

[0027] <Drive Mechanism> The drive mechanism (20) includes an electric motor (21) and a drive shaft (30). The drive shaft (30) is connected to the electric motor (21).

[0028] (Electric Motor) The electric motor (21) is disposed above the compression mechanism (50) and includes a stator (22) and a rotor (23).

[0029] The stator (22) is fixed to the inner circumferential surface of the body (12) of the casing (11). The rotor (23) passes through the interior of the stator (22) in the vertical direction. A drive shaft (30) is fixed to the interior of the axis of the rotor (23). When the electric motor (21) is energized, the drive shaft (30) is rotated together with the rotor (23).

[0030] (Drive Shaft) The drive shaft (30) is located on the axis of the body (12) of the casing (11). An oil supply pump (30a) is attached to the lower end of the drive shaft (30). The oil supply pump (30a) transports oil stored in the storage section (18). The transported oil is supplied to the compression mechanism (50) and the sliding parts of the drive shaft (30) through an oil passage (30b) inside the drive shaft (30).

[0031] The drive shaft (30) has a main shaft portion (31) and an eccentric portion (32). The eccentric portion (32) is eccentric from the center of rotation of the main shaft portion (31). An upper portion of the main shaft portion (31) is fixed to the rotor (23) of the electric motor (21). The axis of the eccentric portion (32) is eccentric from the axis of the main shaft portion (31) by a predetermined amount.

[0032] The main shaft portion (31) of the drive shaft (30) above the eccentric portion (32) is located inside a front through-hole (52c) of a front head (52) described later and is rotatably supported. The main shaft portion (31) of the drive shaft (30) below the eccentric portion (32) is located inside a rear through-hole (53c) of a rear head (53) and is rotatably supported.

[0033] <Compression Mechanism> The compression mechanism (50) is housed in the casing (11) and disposed below the electric motor (21). The compression mechanism (50) includes a cylinder (51), a front head (52), a rear head (53), and a piston (60). The cylinder (51), the front head (52), and the rear head (53) are integrated with each other via a fastening member (54).

[0034] The cylinder (51) is a cylindrical member that covers the outer periphery of the eccentric portion (32). The cylinder (51) is fixed to the inner circumferential surface of the lower part of the body portion (12) of the casing (11). The cylinder (51) is formed in a flat, approximately annular shape.

[0035] A circular compression chamber (55) is formed in the center of the cylinder (51). A radially extending suction port (56) is formed in the cylinder (51). The outlet end of the suction port (56) communicates with the compression chamber (55). The inlet end of the suction port (56) is connected to the suction pipe (40).

[0036] The front head (52) is stacked on the upper end of the cylinder (51). The front head (52) is arranged so as to cover the internal space of the cylinder (51) from above. The front head (52) has a front plate portion (52a) and a front protrusion portion (52b).

[0037] The front plate portion (52a) is a flat annular portion stacked on the cylinder (51). The front protrusion portion (52b) is a cylindrical portion protruding upward from the center of the front plate portion (52a). A front through-hole (52c) is formed in the center of the front plate portion (52a) and the front protrusion portion (52b) so that the main shaft portion (31) of the drive shaft (30) passes through the front plate portion (52a). The front head (52) is formed with a discharge passage (not shown) that passes through the front plate portion (52a) in the up-down direction (axial direction).

[0038] The rear head (53) is stacked on the lower end of the cylinder (51). The rear head (53) is arranged so as to cover the internal space of the cylinder (51) from below. The rear head (53) has a rear plate portion (53a) and a rear protrusion portion (53b).

[0039] The rear plate (53a) is a flat annular portion that is stacked on the cylinder (51). The rear protrusion (53b) is a cylindrical portion that protrudes downward from the center of the rear plate (53a). A rear through-hole (53c) is formed in the center of the rear plate (53a) and the rear protrusion (53b) so that the main shaft (31) of the drive shaft (30) passes through.

[0040] The piston (60) is accommodated inside the cylinder (51). The cylinder (51) and the piston (60) form a compression chamber (55). The piston (60) is formed in a perfect circular ring shape. A cylindrical eccentric part (32) is fitted inside the piston (60). The inside of the compression chamber (55) is partitioned into a low-pressure chamber and a high-pressure chamber by a blade (not shown). The compression mechanism (50) of this embodiment is a so-called swing piston type compression mechanism (50).

[0041] —Operation of the Compressor— The piston (60) rotates eccentrically in the compression chamber (55) as the drive shaft (30) is driven to rotate. As the volume of the low-pressure chamber gradually increases with the eccentric rotation of the piston (60), refrigerant flowing through the suction pipe (40) is drawn into the low-pressure chamber through the suction port (56). When the low-pressure chamber is isolated from the suction port (56), the isolated space forms a high-pressure chamber.

[0042] As the piston (60) further rotates eccentrically, the volume of the high-pressure chamber gradually decreases, and the internal pressure of the high-pressure chamber increases. When the internal pressure of the high-pressure chamber exceeds a predetermined pressure, a reed valve (not shown) opens, and the refrigerant in the high-pressure chamber flows out of the compression mechanism (50) through a discharge passage.

[0043] This high-pressure refrigerant flows upward in the internal space of the casing (11) and passes through a core cut (not shown) of the electric motor (21), etc. The high-pressure refrigerant flowing out above the electric motor (21) is sent to the refrigerant circuit through the discharge pipe (16).

[0044] Configuration of Accumulator An accumulator (45) is connected to the upstream side of the compressor (10). The accumulator (45) temporarily stores the refrigerant before it is sucked into the compressor (10) and separates the liquid refrigerant contained in the gas refrigerant into gas and liquid phases.

[0045] The accumulator (45) has a sealed container (46), an inlet pipe (47), and an outlet pipe (48). The inlet pipe (47) allows the refrigerant to flow into the sealed container (46). The outlet pipe (48) allows the refrigerant to flow out of the sealed container (46).

[0046] The sealed container (46) is formed of a vertically long cylindrical member. An inlet pipe (47) is connected to the top of the sealed container (46). The lower end of the inlet pipe (47) opens at a position near the top of the internal space of the sealed container (46).

[0047] An outlet pipe (48) is connected to the lower part of the sealed container (46). The outlet pipe (48) is made of an iron-based material (e.g., SPCC, SPCD, etc.). The outlet pipe (48) extends upward within the sealed container (46). An upper end of the outlet pipe (48) opens at a position near the upper part of the internal space of the sealed container (46). The outlet pipe (48) extends downward from the lower end of the sealed container (46) and then bends toward the suction pipe (40) of the compressor (10). The lower end of the outlet pipe (48) is connected to the inlet end of the suction pipe (40).

[0048] --Detailed Configuration of the Suction Pipe and Its Surroundings-- As shown in FIG. 2, the suction pipe (40) communicates with the suction port (56) of the cylinder (51), and is disposed inside the joint pipe (43).

[0049] (Joint Pipe) The joint pipe (43) is fixed to the through hole (15) of the casing (11). The inner peripheral surface of the joint pipe (43) and the inner peripheral surface of the through hole (15) of the casing (11) are generally coincident with each other. In other words, the inner peripheral surface of the joint pipe (43) and the inner peripheral surface of the through hole (15) of the casing (11) are continuous with each other. The through hole (15) of the casing (11) is formed in the lower part of the body portion (12) of the casing (11). The through hole (15) of the casing (11) is formed in a position facing the suction port (56). In other words, the joint pipe (43) is disposed so as to face the suction port (56) of the cylinder (51).

[0050] The joint pipe (43) is made of an iron-based material (e.g., SPCC, SPCD, etc.). The joint pipe (43) is a cylindrical member. The joint pipe (43) extends from the body portion (12) of the casing (11) toward the outside of the casing (11). The thickness of the joint pipe (43) is greater than the thickness of the casing (11). The inner diameter of the joint pipe (43) is constant over the entire axial length.

[0051] The joint pipe (43) is fixed with its tip in contact with the trunk portion (12) of the casing (11). Specifically, the joint pipe (43) is fixed to the trunk portion (12) of the casing (11) by being welded. The joint pipe (43) has a welded portion (43a). The welded portion (43a) is formed around the entire outer edge of the joint pipe (43) on the casing (11) side.

[0052] (Suction Pipe) The suction pipe (40) passes through the inside of the joint pipe (43) and extends to the outside of the casing (11). The suction pipe (40) is made of an iron-based material (e.g., SPCC, SPCD, etc.). The suction pipe (40) is a cylindrical member. The suction pipe (40) has a large diameter portion (41) and a small diameter portion (42).

[0053] The large diameter portion (41) is formed on the inlet side of the suction pipe (40). The large diameter portion (41) is fixed to the inner circumferential surface of the joint pipe (43). The outlet end of the outlet pipe (48) is fixed to the inner circumferential surface of the large diameter portion (41).

[0054] The small diameter portion (42) is formed on the outflow side of the suction pipe (40). The outer diameter of the small diameter portion (42) is smaller than the outer diameter of the large diameter portion (41). The small diameter portion (42) includes a main body portion (42a) and a step portion (42b). The main body portion (42a) is provided on the outflow side of the small diameter portion (42). The outflow end of the main body portion (42a) is connected to the suction port (56) of the cylinder (51). The outer diameter of the main body portion (42a) is smaller than the inner diameter of the through hole (15) of the casing (11). The main body portion (42a) passes through the through hole (15) of the casing (11).

[0055] The step (42b) is provided midway along the suction pipe (40) and is continuous with the inlet end of the main body (42a). The step (42b) connects the main body (42a) and the large diameter portion (41). The outer and inner diameters of the step (42b) gradually increase from the main body (42a) toward the large diameter portion (41).

[0056] The inlet end (E) of the stepped portion (42b) of the small diameter portion (42) is located closer to the accumulator (45) than the axial center portion (C) of the joint pipe (43). A first gap (S1) is formed between the outer peripheral surface of the small diameter portion (42) and the inner peripheral surface of the joint pipe (43). The first gap (S1) is continuous from the end of the joint pipe (43) on the casing (11) side to the connection portion of the suction pipe (40) with the large diameter portion (41). In other words, the suction pipe (40) does not contact the joint pipe (43) from the end of the joint pipe (43) on the casing (11) side to the connection portion of the suction pipe (40). The first gap (S1) corresponds to the gap of the present disclosure.

[0057] In this manner, the first gap (S1) is continuously formed between the outer peripheral surface of the small diameter portion (42) of the suction pipe (40) and the inner peripheral surface of the joint pipe (43), so that even if vibrations generated in the compression mechanism (50) are transmitted to the suction pipe (40), the small diameter portion (42) vibrates without coming into contact with the joint pipe (43), thereby damping the vibrations in the small diameter portion (42).

[0058] Furthermore, a second annular gap (S2) is formed between the main body (42a) of the small diameter portion (42) and the through-hole (15) of the casing (11). In the small diameter portion (42), a space including the first gap (S1) and the second gap (S2) is formed between the connection portion of the compression mechanism (50) and the large diameter portion (41). This space allows the small diameter portion (42) to vibrate. This allows further damping of vibration in the small diameter portion (42).

[0059] Furthermore, the inlet end (E) of the small diameter portion (42) is located closer to the accumulator (45) than the axial center (C) of the joint pipe (43), thereby making it possible to lengthen the small diameter portion (42) of the suction pipe (40), thereby further damping vibrations in the small diameter portion (42).

[0060] Here, the total axial length of the suction pipe (40) is denoted by L1, and the axial length of the small diameter portion (42) of the suction pipe (40) is denoted by L2. In the compressor (10) of this embodiment, L2 is equal to or greater than 58% of L1 (L2≧L1×0.58).

[0061] The joint pipe (43) is made of an iron-based material, which increases the rigidity of the joint pipe (43). As a result, vibrations transmitted from the compression mechanism (50) are insulated at the connection between the large diameter portion (41) of the suction pipe (40) and the joint pipe (43), and are less likely to be transmitted to the accumulator (45).

[0062] Furthermore, since the joint pipe (43) is connected to the casing by the welded portion (43a), the rigidity of the welded portion (43a) is high, thereby enabling the joint pipe (43) to further insulate the vibrations transmitted from the compression mechanism (50) to the suction pipe (40).

[0063] -Method of Connecting the Accumulator- Next, a method of connecting the accumulator (45) to the compression mechanism (50) will be described. The compressor (10) of this embodiment is manufactured by connecting the accumulator (45) to the compression mechanism (50). The method of connecting the accumulator involves a welding step, a press-fitting step, a fitting step, and a brazing step, performed in this order.

[0064] The welding step is a step of fixing the joint pipe (43) to the casing (11). In the welding step, first, the joint pipe (43) is brought into contact with the trunk portion (12) of the casing (11) so that the inner peripheral surface of the through hole (15) formed in the casing (11) and the inner peripheral surface of the joint pipe (43) coincide with each other. Next, the joint pipe (43) brought into contact with the trunk portion (12) is welded to the casing (11). This forms a welded portion (43a).

[0065] The press-fitting step is a step of press-fitting the suction pipe (40) into the compression mechanism (50). In the press-fitting step, first, the compression mechanism (50) is positioned so that the suction port (56) of the cylinder (51) of the compression mechanism (50) faces the joint pipe (43). Next, the suction pipe (40) is press-fitted from the open side of the joint pipe (43) into the suction port (56) of the cylinder (51).

[0066] At this time, the suction pipe (40) is press-fitted in the axial direction so as to form a first gap (S1) between the outer peripheral surface of the small diameter portion (42) of the suction pipe (40) and the inner peripheral surface of the joint pipe (43). Specifically, the suction pipe (40) is press-fitted so that the axial length of the suction pipe (40) at the first gap (S1) is a predetermined length.

[0067] In the fitting step, the outlet pipe (48) of the accumulator (45) is fitted into the open end of the suction pipe (40).

[0068] In the brazing step, the outlet pipe (48) and the suction pipe (40), and the suction pipe (40) and the joint pipe (43) are fixed together by brazing.

[0069] Experimental Example 1 FIG. 3 is a graph showing the relationship between the rotation speed and the sound intensity obtained by measuring the compressor (10).

[0070] The solid line connecting the circles in the figure represents the results of measurement of a compressor in which the first gap (S1) is not formed between the outer peripheral surface of the small diameter portion (42) of the suction pipe (40) and the inner peripheral surface of the joint pipe (43). The solid line connecting the crosses in the figure represents the results of measurement of the compressor (10) of this embodiment. Specifically, the results represent the results of measurement of the compressor (10) in which the first gap (S1) is formed between the outer peripheral surface of the small diameter portion (42) and the inner peripheral surface of the joint pipe (43). The joint pipe (43) in this experiment was made of an iron-based material.

[0071] In the figure, it was confirmed that when the rotation speed is 70 rpm or more, the compressor (10) of this embodiment produces less noise than a compressor that does not have the first gap (S1) between the small diameter portion (42) and the joint pipe (43). This confirms that the formation of the first gap (S1) between the outer peripheral surface of the small diameter portion (42) and the inner peripheral surface of the joint pipe (43) makes it possible to suppress vibrations transmitted from the compression mechanism (50) to the accumulator (45).

[0072] Experimental Example 2 Figure 4 is a graph showing the relationship between L2 / L1 and the peak value of acceleration of the accumulator, obtained from a simulation. Specifically, Figure 4 is a graph plotting the peak value of acceleration of the vibration of the accumulator (45) when a force of 1 N is applied to the suction pipe (40). Figure 4 plots the peak value of acceleration of the accumulator (45) in the compressor (10) when the ratio of L2 / L1 is 57%, 64%, and 76%.

[0073] In the figure, it was confirmed that when the ratio L2 / L1 is 58% or more, the peak value of the acceleration of the accumulator (45) decreases as the ratio L2 / L1 increases. In other words, it was confirmed that the vibration of the accumulator (45) is suppressed as the axial length L2 of the small diameter portion (42) of the suction pipe (40) increases relative to the total axial length L1 of the suction pipe (40).

[0074] From this, it was confirmed that vibration of the accumulator (45) can be suppressed if the axial length L2 of the small diameter portion (42) of the suction pipe (40) is 58% or more of the total axial length L1 of the suction pipe (40).

[0075] -Features of the embodiment- A feature (1) of the present embodiment is that a first gap (S1) is formed between the outer peripheral surface of the small diameter portion (42) of the suction pipe (40) and the inner peripheral surface of the joint pipe (43). As a result, even if vibrations of the compression mechanism (50) are transmitted to the suction pipe (40), the small diameter portion (42) vibrates without coming into contact with the joint pipe (43), and therefore, the vibrations are damped in the small diameter portion (42).

[0076] In the conventional compressor, the joint pipe (43) is made of a copper-based material, and since the conventional joint pipe (43) has low rigidity, vibrations from the compression mechanism (50) are easily transmitted to the joint pipe (43) via the suction pipe (40).

[0077] In this embodiment, the joint pipe (43) is made of an iron-based material, and therefore the joint pipe (43) has higher rigidity than a joint pipe made of a copper-based material. This allows the joint pipe (43) to be insulated from vibrations from the compression mechanism (50) at the connection between the large diameter section (41) of the suction pipe (40) and the joint pipe (43). As a result, vibrations transmitted from the compression mechanism (50) to the accumulator (45) can be suppressed.

[0078] In addition, since the joint pipe (43) is made of an iron-based material, the cost can be reduced compared to when the joint pipe (43) is made of a copper-based material.

[0079] A feature (2) of this embodiment is that the first gap (S1) is formed continuously from the end of the joint pipe (43) on the casing (11) side to the connection portion with the suction pipe (40). This allows the small diameter portion (42) of the suction pipe (40) to vibrate without being hindered by the joint pipe (43), thereby further damping the vibrations.

[0080] A feature (3) of this embodiment is that the inlet end (E) of the small diameter portion (42) is located closer to the accumulator (45) than the axial center (C) of the joint pipe (43). This allows the small diameter portion (42) of the suction pipe (40) to be longer, thereby further damping vibrations.

[0081] A feature (4) of this embodiment is that the joint pipe (43) has a welded portion (43a) welded to the casing (11). This increases the rigidity of the joint portion between the joint pipe (43) and the casing (11), thereby enabling the joint pipe (43) to better insulate against vibrations from the compression mechanism (50).

[0082] In conventional compressors, the joint pipe (43) and the casing (11) are joined by silver brazing. In the compressor (10) of the present embodiment, the joint pipe (43) and the casing (11) are joined by welding, which can reduce costs compared to silver brazing.

[0083] A feature (5) of this embodiment is that the thickness of the joint pipe (43) is greater than the thickness of the casing (11), which makes it possible to suppress deformation of the joint pipe (43) due to heat when the joint pipe (43) and the casing (11) are welded together.

[0084] A feature (6) of this embodiment is that the outlet pipe (48) is made of an iron-based material. In conventional compressors, the outlet pipe is made of a copper pipe connected to an iron pipe. Since the outlet pipe (48) of this embodiment is made of only an iron-based material, the rigidity of the outlet pipe (48) can be increased. This allows the outlet pipe (48) to further insulate vibrations from the compression mechanism (50). Furthermore, the outlet pipe (48) of this embodiment can reduce the number of components of the outlet pipe (48) and also reduce material costs, thereby reducing costs.

[0085] A seventh feature of this embodiment is that the axial length L2 of the small diameter portion (42) of the suction pipe (40) is equal to or greater than 58% of the total axial length L1 of the suction pipe (40). Since the small diameter portion (42) is long to some extent, vibrations from the compression mechanism (50) are more likely to be damped by the small diameter portion (42) of the suction pipe (40).

[0086] A feature (8) of this embodiment is that the accumulator (45) includes a casing (11), a compression mechanism (50) accommodated in the casing (11) and having an intake port (56), a joint pipe (43) fixed to the casing (11), a suction pipe (40) disposed inside the joint pipe (43) and communicating with the suction port (56) of the compression mechanism (50), and an outlet pipe (48) connected to the inlet end of the suction pipe (40), and the suction pipe (40) includes a large diameter portion (41) formed on the inlet side of the suction pipe (40) and fixed to the inner peripheral surface of the joint pipe (43), and a large diameter portion (42) formed on the outlet side of the suction pipe (40) and fixed to the inner peripheral surface of the joint pipe (43). a casing (11) having a through hole (15) formed therein, the inner diameter of the through hole (15) being larger than the outer diameter of the small diameter portion (42), the method comprising: a welding step of welding a coupling pipe (43) made of an iron-based material to the casing (11); and a press-fitting step of press-fitting the suction pipe (40) into the suction port (56) of the compression mechanism (50), wherein in the press-fitting step, a first gap (S1) is formed between an outer peripheral surface of the small diameter portion (42) of the suction pipe (40) and an inner peripheral surface of the coupling pipe (43), and a second gap (S2) is formed between the small diameter portion (42) and the through hole (15).

[0087] As a result, when vibrations of the compression mechanism (50) are transmitted to the suction pipe (40), the first gap (S1) and the second gap (S2) allow the small diameter portion (42) to vibrate without coming into contact with the joint pipe (43), and therefore the vibrations of the compression mechanism (50) can be damped by the small diameter portion (42).

[0088] In addition, since the inner diameter of the through hole (15) of the casing (11) is larger than the outer diameter of the small diameter portion (42), a second gap (S2) is formed, which makes it easier to align the intake pipe (40) with the intake port (56) of the compression mechanism (50) during the press-fitting process.

[0089] - Modifications of the Embodiment - <Modification 1> In the compressor (10) of this embodiment, the tip of the joint pipe (43) may be fitted into the through-hole (15) of the casing (11). In this modification, a first gap (S1) is also formed between the outer peripheral surface of the small diameter portion (42) of the suction pipe (40) and the inner peripheral surface of the joint pipe (43). This provides the same effects as those of the embodiment.

[0090] 5, the cylinder (51) and the piston (60) are spaced apart in the vertical direction (axial direction). Specifically, the compression mechanism (50) includes a front head (52), a front cylinder (51), a middle plate (58), a rear cylinder (51), and a rear head (53).

[0091] The front and rear cylinders (51, 51) each contain a piston (60, 60). The front and rear cylinders (51, 51) each have a suction port (56, 56) formed therein and extending in the radial direction.

[0092] The drive shaft (30) is provided with two eccentric portions (32, 32) corresponding to the front and rear pistons (60, 60). The eccentric portion (32) is fitted into the piston (60).

[0093] The body (12) of the casing (11) is formed with through holes (15, 15) at positions facing the front and rear suction ports (56, 56), respectively. Joint pipes (43, 43) are connected to the through holes (15) of the casing (11), respectively.

[0094] The suction pipes (40, 40) are connected to the suction ports (56, 56) of the front and rear cylinders (51, 51), respectively, and extend through the inside of the joint pipes (43, 43) to the outside of the casing (11). The front and rear suction pipes (40, 40) are connected to outlet pipes (48, 48) of the accumulator (45), respectively.

[0095] As described above, this modified example is directed to a two-cylinder compressor (10) having two cylinders (51, 51) and two pistons (60, 60). In the two-cylinder compressor (10), a first gap (S1) is also formed between the outer peripheral surface of the small diameter portion (42) of one suction pipe (40) and the inner peripheral surface of one joint pipe (43). In addition, a space including the first gap (S1) and the second gap (S2) is formed in the small diameter portion (42) between the connection portion of the compression mechanism (50) and the large diameter portion (41).

[0096] In this modification, as in the embodiment, it is possible to suppress vibrations transmitted from the compression mechanism (50) to the accumulator (45). In addition, since the outlet pipe (48) is made only of iron-based materials, it is possible to further reduce the number of parts and reduce costs.

[0097] Although the embodiments and modifications have been described above, it will be understood that various modifications in form and details are possible without departing from the spirit and scope of the claims. Furthermore, the above embodiments, modifications, and other embodiments may be combined or substituted as appropriate as long as the functionality of the subject matter of the present disclosure is not impaired.

[0098] Other Embodiments The above-described embodiment may be configured as follows.

[0099] The compression mechanism (50) of the compressor (10) in the above embodiment is of a rocking piston type. However, the compression mechanism (50) may be of a rolling piston type. In this compression mechanism (50), the compression chamber (55) is divided by a vane separate from the piston (60), instead of the blade of the above embodiment.

[0100] As described above, the present disclosure is useful for rotary compressors.

[0101] 10 Compressor (rotary compressor) 11 Casing 40 Intake pipe 41 Large diameter section 42 Small diameter section 43 Joint pipe 43a Welded section 45 Accumulator 48 Outlet pipe 50 Compression mechanism 56 Intake port S1 First gap (gap) S2 Second gap

Claims

DEPCT661. Rotary compressor assembled with: housing (11); compression mechanism (50) which is housed in the housing (11) and has a suction port (56); coupling pipe (43) which is firmly attached to the housing (11); suction pipe (40) which is placed inside the coupling pipe (43) and connects to the suction port (56) of the compression mechanism (50); and accumulator (45) which includes an outlet pipe (48) connected to the inlet end of the suction pipe (40); suction pipe (40) with a large diameter section (41) formed on the outlet side. The diameter of the suction pipe (40) is firmly attached to the inner circumferential surface of the coupling (43), and the small diameter section (42) is formed on the outlet side of the suction pipe (40) and has an outer diameter smaller than the diameter (41) coupling (43) which is made of an iron-based material. The gap (S1) is formed between the outer circumferential surface of the small diameter section (42) of the suction pipe (40) and the inner circumferential surface of the coupling (43).2.Rotary compressor of claim 1, in which the end (E) of the small diameter section (42) on the inlet side is closer to the accumulator (45) than the middle section 4 of the coupling pipe (43) in the axial direction; 3. Rotary compressor of claim 1 or 2, in which the coupling pipe (43) has a weld (43a) to the housing (11); 4. Rotary compressor of claim 3, in which the thickness of the coupling pipe (43) is greater than the thickness of the housing (11); 5. Rotary compressor of any of claims 1 through 4, in which the outlet pipe (48) is made of a steel-based material; 6. Rotary compressor (10) of any of claims 1 through 5, in which the axial length L2 of the small diameter section (42) of the suction pipe (40) is greater than or equal to 58% of the total axial length L1 of the suction pipe (40);