Compressors and refrigeration cycle equipment

Abstract

In a compressor, damage to the drive shaft supported by the boss portion is suppressed. [Solution] The compression mechanism (30) of the compressor (10) is equipped with a boss portion (42). The boss portion (42) is a cylindrical portion that protrudes toward the electric motor (20) and constitutes a sliding bearing. The boss portion (42) is divided into a protruding end (51), a base end (52), and an intermediate portion (53). The protruding end (51) includes one end of the boss portion (42) toward the electric motor (20). The base end (52) includes the other end of the boss portion (42) located on the opposite side from the protruding end (51). The intermediate portion (53) is located between the base end (52) and the protruding end (51). The intermediate portion (53) is thinner than the protruding end (51) and the base end (52).

Description

Technical Field

[0001] The present disclosure relates to a compressor and a refrigeration cycle apparatus. Background Art

[0002] Patent Document 1 discloses a rotary compressor, which is a type of compressor. This rotary compressor is provided, for example, in a refrigerant circuit of a refrigeration cycle apparatus, and sucks and compresses refrigerant.

[0003] In a rotary compressor, a compression mechanism and an electric motor are connected via a drive shaft. The compression mechanism includes a boss portion. The boss portion is a cylindrical portion protruding toward the electric motor side. The drive shaft is inserted through the boss portion. The boss portion constitutes a slide bearing that supports the drive shaft. Prior Art Documents Patent Documents

[0004] Patent Document 1 Japanese Unexamined Patent Publication No. 2022-151690 Summary of the Invention Problem to be Solved by the Invention

[0005] In a compressor, a rotor of an electric motor is attached to a drive shaft. During operation of the compressor, a centrifugal force generated by rotation of the rotor acts on a portion of the drive shaft where the rotor is attached. This centrifugal force bends the drive shaft, which may cause the drive shaft to contact the vicinity of a protruding end of the boss portion. When the drive shaft contacts the boss portion, if the load (contact surface pressure) acting on the contact portion between the drive shaft and the boss portion becomes excessive, the drive shaft and the boss portion may be damaged.

[0006] An object of the present disclosure is to suppress damage to a drive shaft and a boss portion in a compressor. Means for Solving the Problem

[0007] A first aspect of the present disclosure is a compressor (10) comprising a compression mechanism (30) for drawing in and compressing a fluid, a drive shaft (25) for driving the compression mechanism (30), and an electric motor (20) having a rotor (22) attached to the drive shaft (25), wherein the compression mechanism (30) comprises a cylindrical boss portion (42) protruding toward the electric motor (20), the boss portion (42) constitutes a sliding bearing for supporting the drive shaft (25), and the boss portion (42) is divided into a protruding end (51) including one end toward the electric motor (20), a base end (52) including the other end opposite to the protruding end (51), and an intermediate portion (53) located between the base end (52) and the protruding end (51) and having a thinner wall thickness than the protruding end (51) and the base end (52).

[0008] In the compressor (10) of the first embodiment, the boss portion (42) of the compression mechanism (30) is divided into a base portion (52), an intermediate portion (53), and a protruding portion (51). The thickness of the intermediate portion (53) is thinner than that of the base portion (52) and thinner than that of the protruding portion (51). The rigidity of the intermediate portion (53) is lower than that of the base portion (52) and lower than that of the protruding portion (51). Therefore, when the drive shaft (25) deforms during the operation of the compressor (10), the deformation of the intermediate portion (53) causes a slight displacement of the protruding portion (51). As a result, even when the drive shaft (25) comes into contact with the protruding portion (51) of the boss portion (42), the load (contact pressure) acting on the contact portion between the drive shaft (25) and the protruding portion (51) is kept low, and damage to the drive shaft (25) and the protruding portion (51) is suppressed. Furthermore, since the rigidity of the tip (51) is higher than that of the intermediate section (53), excessive displacement of the tip (51) is suppressed.

[0009] A second aspect of the present disclosure is the first aspect, wherein the tip (51) comprises a thickness-increasing portion (51a) whose thickness gradually increases from the intermediate portion (53) toward one end of the boss portion (42).

[0010] In a second embodiment, the tip (51) is provided with a thickness-increasing portion (51a). This thickness-increasing portion (51a) constitutes a part or the whole of the tip (51).

[0011] A third aspect of the present disclosure is, in the first aspect, the base portion (52) comprises a thickness-increasing portion (52a) whose thickness gradually increases from the intermediate portion (53) toward the other end of the boss portion (42).

[0012] In a third embodiment, the base end (52) is provided with a thickness-increasing portion (52a). This thickness-increasing portion (52a) constitutes a part or the whole of the base end (52).

[0013] A fourth aspect of the present disclosure is, in the first aspect, the tip (51) comprises a first thickness-increasing portion (51a) in which the thickness gradually increases from the intermediate portion (53) toward one end of the boss portion (42), and the base portion (52) comprises a second thickness-increasing portion (52a) in which the thickness gradually increases from the intermediate portion (53) toward the other end of the boss portion (42), wherein the maximum thickness of the base portion (52) is greater than the maximum thickness of the tip (51).

[0014] In the fourth embodiment, the protruding end (51) is provided with a first thickness-increasing portion (51a), and the base end (52) is provided with a second thickness-increasing portion (52a). The first thickness-increasing portion (51a) constitutes a part or the whole of the protruding end (51). The second thickness-increasing portion (52a) constitutes a part or the whole of the base end (52). The maximum thickness of the base end (52) is greater than the maximum thickness of the protruding end (51). Therefore, the rigidity of the base end (52) is higher than that of the protruding end (51). As a result, deformation of the base end (52) during the operation of the compressor (10) is suppressed, and excessive displacement of the protruding end (51) is suppressed.

[0015] A fifth aspect of the present disclosure, in any one of the first to fourth aspects, the compression mechanism (30) comprises a cylinder (70), a cylindrical roller (80) housed in the cylinder (70) and driven by the drive shaft (25) to rotate eccentrically, a vane (81) partitioning a fluid chamber (31) formed between the cylinder (70) and the roller (80), and a front head (40) positioned on the electric motor (20) side of the cylinder (70), wherein the front head (40) comprises a boss portion (42) and a flat plate portion (41) covering one end face of the cylinder (70), and the boss portion (42) protrudes from the flat plate portion (41) toward the electric motor (20).

[0016] In the fifth embodiment of the compressor (10), the compression mechanism (30) comprises rollers (80) and vanes (81). This embodiment of the compressor (10) is a rotary compressor. In the compression mechanism (30), a boss portion (42) is provided on the front head (40).

[0017] A sixth aspect of this disclosure is a refrigeration cycle device (100) that includes a refrigerant circuit (110) provided with a compressor (10) according to any one of the first to fifth aspects described above, and which circulates a refrigerant in the refrigerant circuit (110) to perform a refrigeration cycle.

[0018] In the refrigeration cycle device (100) of the sixth embodiment, one of the first to fifth compressors (10) is provided in the refrigerant circuit (110) and sucks in and compresses refrigerant. [Brief explanation of the drawing]

[0019] [Figure 1] Figure 1 is a piping diagram showing the configuration of the refrigeration cycle system of the embodiment. [Figure 2] Figure 2 is a longitudinal cross-sectional view of the compressor according to the embodiment. [Figure 3] Figure 3 is an enlarged view of the compression mechanism shown in Figure 2. [Figure 4A] Figure 4A is a cross-sectional view of the compression mechanism showing the IVA-IVA section in Figure 3. [Figure 4B] FIG. 4B is a cross-sectional view of a compression mechanism showing the IVB-IVB cross-section in FIG. 3. [Figure 5] FIG. 5 is a cross-sectional view of a front head constituting the compression mechanism of the embodiment. [Figure 6] FIG. 6 is a cross-sectional view of a front head constituting a compression mechanism according to a first modification. [Figure 7] FIG. 7 is a cross-sectional view of a front head constituting a compression mechanism according to a second modification. [Figure 8] FIG. 8 is a cross-sectional view of a front head constituting a compression mechanism according to a third modification. [Figure 9] FIG. 9 is a cross-sectional view of a front head constituting a compression mechanism according to a fourth modification. [Figure 10] FIG. 10 is a cross-sectional view of a front head constituting a compression mechanism according to a fifth modification. MODE FOR CARRYING OUT THE INVENTION

[0020] An embodiment will be described. The present embodiment is an air conditioner (100) including a compressor (10). The air conditioner (100) is a refrigeration cycle apparatus that performs a vapor compression refrigeration cycle.

[0021] -Air Conditioner- As shown in FIG. 1, the air conditioner (100) includes an outdoor unit (101) and an indoor unit (102). The air conditioner (100) also includes a refrigerant circuit (110). The refrigerant circuit (110) is provided with the compressor (10), an outdoor heat exchanger (111), an expansion valve (112), an indoor heat exchanger (113), a four-way switching valve (114), and an accumulator (115).

[0022] The outdoor unit (101) houses a compressor (10), an outdoor heat exchanger (111), an expansion valve (112), a four-way switching valve (114), and an accumulator (115). The outdoor unit (101) is also equipped with an outdoor fan (106). The indoor unit (102) houses an indoor heat exchanger (113). The indoor unit (102) is also equipped with an indoor fan (107).

[0023] The refrigerant circuit (110) is constructed by connecting a compressor (10), an outdoor heat exchanger (111), an expansion valve (112), an indoor heat exchanger (113), a four-way directional valve (114), and an accumulator (115) with piping. The discharge pipe of the compressor (10) is connected to the first port of the four-way directional valve (114). The suction pipe of the compressor (10) is connected to the second port of the four-way directional valve (114) via the accumulator (115). In the refrigerant circuit (110), the outdoor heat exchanger (111), the expansion valve (112), and the indoor heat exchanger (113) are arranged in order from the third port to the fourth port of the four-way directional valve (114).

[0024] The four-way switching valve (114) switches between a first state, shown by a solid line in Figure 1, and a second state, shown by a dashed line in Figure 2. In the first state, the four-way switching valve (114) communicates with the third port and the second port communicates with the fourth port. In the second state, the four-way switching valve (114) communicates with the fourth port and the second port communicates with the third port.

[0025] <Operation> The air conditioner (100) selectively performs cooling and heating operations.

[0026] In cooling operation, the four-way switching valve (114) is set to the first state, and the refrigerant circulates in the refrigerant circuit (110). In the refrigerant circuit (110), the outdoor heat exchanger (111) functions as a heat radiator, and the indoor heat exchanger (113) functions as an evaporator. The indoor unit (102) cools the air drawn in from the indoor space by the indoor heat exchanger (113), and blows the cooled air back into the indoor space.

[0027] During heating operation, the four-way switching valve (114) is set to the second state, and the refrigerant circulates in the refrigerant circuit (110). In the refrigerant circuit (110), the indoor heat exchanger (113) functions as a radiator, and the outdoor heat exchanger (111) functions as an evaporator. The indoor unit (102) heats the air drawn in from the indoor space using the indoor heat exchanger (113), and blows the heated air back into the indoor space.

[0028] -Compressor Configuration- The compressor (10) of this embodiment will now be described. The compressor (10) of this embodiment is an oscillating piston type rotary compressor.

[0029] As shown in Figure 2, the compressor (10) comprises a compression mechanism (30), an electric motor (20), a drive shaft (25), and a casing (15).

[0030] <Casing> The casing (15) is a cylindrical sealed container in an upright position. The casing (15) comprises a cylindrical body (16) and a pair of end plates (17a, 17b) that close the ends of the body (16). A discharge pipe (18) is attached to the upper end plate (17a). The discharge pipe (18) passes through the upper end plate (17a). A first suction pipe (19a) and a second suction pipe (19b) are attached to the lower part of the body (16). Each suction pipe (19a, 19b) passes through the body (16).

[0031] <Electric motor> The electric motor (20) is positioned in the upper part of the internal space of the casing (15). The electric motor (20) comprises a stator (21) and a rotor (22). The stator (21) is fixed to the body (16) of the casing (15). The rotor (22) is attached to the main shaft (26) of the drive shaft (25), which will be described later.

[0032] <Drive shaft> The drive shaft (25) comprises a main shaft portion (26), a first eccentric portion (27a), and a second eccentric portion (27b).

[0033] The main shaft portion (26) is a rod-shaped part that extends from the upper end to the lower end of the drive shaft (25). The central axis of the main shaft portion (26) coincides with the rotational axis of the drive shaft (25). The upper part of the main shaft portion (26) is inserted through the rotor (22) of the electric motor (20).

[0034] The first eccentric portion (27a) and the second eccentric portion (27b) are each cylindrical parts with a larger diameter than the main shaft portion (26). The first eccentric portion (27a) and the second eccentric portion (27b) are located below the drive shaft (25). The first eccentric portion (27a) and the second eccentric portion (27b) are each eccentric with respect to the central axis of the main shaft portion (26). The eccentric direction of the first eccentric portion (27a) with respect to the central axis of the main shaft portion (26) and the eccentric direction of the second eccentric portion (27b) with respect to the central axis of the main shaft portion (26) are offset by 180°.

[0035] The portion of the main shaft (26) adjacent to the upper side of the first eccentric portion (27a) constitutes the main journal portion (28). The main journal portion (28) is the portion inserted through the front head (40) of the compression mechanism (30), which will be described later. The main journal portion (28) is supported by the boss portion (42) of the compression mechanism (30), which will be described later.

[0036] The portion of the main shaft (26) adjacent to the lower side of the second eccentric portion (27b) constitutes the secondary journal portion (29). The secondary journal portion (29) is the portion inserted through the rear head (60) of the compression mechanism (30), which will be described later. The secondary journal portion (29) is supported by the cylindrical portion (62) of the compression mechanism (30), which will be described later.

[0037] -Compression mechanism configuration- As shown in Figures 3, 4A, and 4B, the compression mechanism (30) comprises two cylinders (70, 75), two rollers (80, 85), and two vanes (81, 86). Each of the first cylinder (70) and the second cylinder (75) is provided with a pair of bushings (82, 87). The compression mechanism (30) also comprises one front head (40), one intermediate plate (35), and one rear head (60). Note that the number of cylinders (70, 75), rollers (80, 85), and vanes (81, 86) provided in the compression mechanism (30) is not limited to two of each.

[0038] In the compression mechanism (30), the front head (40), the first cylinder (70), the intermediate plate (35), the second cylinder (75), and the rear head (60) are arranged in order from top to bottom. In the compression mechanism (30), the front head (40) is fixed to the body (16) of the casing (15).

[0039] <Cylinder> The first cylinder (70) and the second cylinder (75) are each thick-walled disc-shaped members. Each cylinder (70, 75) has a cylinder bore (71, 76) and blade housing holes (72, 77). The first cylinder (70) has a first intake port (73). The second cylinder (75) has a second intake port (78).

[0040] In the first cylinder (70) and the second cylinder (75), the cylinder bores (71, 76) are circular holes that penetrate the cylinders (70, 75) in the thickness direction. The cylinder bores (71, 76) are formed in the central part of the cylinders (70, 75). The first roller (80) is housed in the cylinder bore (71) of the first cylinder (70). The second roller (85) is housed in the cylinder bore (76) of the second cylinder (75).

[0041] In the first cylinder (70), a first fluid chamber (31) is formed between the wall surface of the cylinder bore (71) and the first roller (80). In the second cylinder (75), a second fluid chamber (32) is formed between the wall surface of the cylinder bore (71, 76) and the second roller (85), which will be described later.

[0042] The blade housing holes (72, 77) are holes that extend radially outward from the inner circumferential surface of the cylinder (70, 75) (i.e., the outer edge of the cylinder bore (71, 76)). These blade housing holes (72, 77) penetrate the cylinder (70, 75) in the thickness direction. The first vane (81) is housed in the blade housing hole (72) of the first cylinder (70). The second vane (86) is housed in the blade housing hole (77) of the second cylinder (75).

[0043] In both the first cylinder (70) and the second cylinder (75), the intake ports (73, 78) are located to the right of the blade housing holes (72, 77) in Figures 4A and 4B. The intake ports (73, 78) are through-holes extending radially through the cylinders (70, 75). In each cylinder (70, 75), the intake ports (73, 78) open into the cylinder bore (71, 76).

[0044] <Front Head> The front head (40) is a member that closes the end face of the first cylinder (70) on the motor (20) side (the upper surface of the first cylinder (70) in Figure 3). The front head (40) comprises a flat plate portion (41), a boss portion (42), and an outer peripheral wall portion (43). The flat plate portion (41), the boss portion (42), and the outer peripheral wall portion (43) are integrally molded.

[0045] The flat plate portion (41) is formed in a generally circular, thick plate shape. The flat plate portion (41) is positioned to cover the end face (upper surface in Figure 3) of the first cylinder (70). The boss portion (42) is a cylindrical portion that extends from the flat plate portion (41) toward the electric motor (20) side (upper side in Figure 3). The boss portion (42) is positioned in the center of the flat plate portion (41). The outer peripheral wall portion (43) is a thick, annular portion formed continuously with the outer peripheral edge of the flat plate portion (41).

[0046] A main through-hole (45) is formed in the front head (40). The main through-hole (45) is a through-hole formed across the boss portion (42) and the flat plate portion (41). One end of the main through-hole (45) opens to the lower surface of the flat plate portion (41) in Figure 3. The other end of the main through-hole (45) opens to the upper end surface of the boss portion (42) in Figure 3. The cross-section of the main through-hole (45) is circular. The diameter of the main through-hole (45) is constant along its entire length. The main journal portion (28) of the drive shaft (25) is inserted through the main through-hole (45). The boss portion (42) constitutes a journal bearing that supports the drive shaft (25).

[0047] A circumferential groove (46) is formed in the flat plate portion (41). The circumferential groove (46) is a circular groove that opens to the lower surface of the flat plate portion (41) in Figure 3. The circumferential groove (46) surrounds the entire lower end of the main insertion hole (45) in Figure 3.

[0048] A first discharge port (44) is formed in the flat plate portion (41). The first discharge port (44) penetrates the flat plate portion (41) in the direction of its thickness. The first discharge port (44) is located to the left of the blade housing hole (72) in Figure 4A. Although not shown, a discharge valve for opening and closing the first discharge port (44) is provided on the upper surface of the flat plate portion (41) in Figure 3.

[0049] <Rear Head> The rear head (60) is a member that closes the end face of the second cylinder (75) on the side opposite to the electric motor (20) (the lower surface of the second cylinder (75) in Figure 3). The rear head (60) comprises a main body (61), a cylindrical part (62), and an outer peripheral wall part (63).

[0050] The main body (61) is formed in the shape of a generally circular thick plate. The main body (61) is positioned to cover the end face (bottom surface in Figure 3) of the second cylinder (75). The cylindrical part (62) is formed in the shape of a cylinder extending from the main body (61) to the side opposite to the second cylinder (75) (the bottom side in Figure 3). The cylindrical part (62) is positioned in the center of the main body (61). The outer peripheral wall part (63) is formed in the shape of a cylinder extending from the outer peripheral edge of the main body (61) to the side opposite to the second cylinder (75).

[0051] A secondary through-hole (65) is formed in the rear head (60). The secondary through-hole (65) is a through-hole formed between the cylindrical portion (62) and the main body portion (61). One end of the secondary through-hole (65) opens to the upper surface of the main body portion (61) in Figure 3. The other end of the secondary through-hole (65) opens to the lower end surface of the cylindrical portion (62) in Figure 3. The cross-section of the secondary through-hole (65) is circular. The diameter of the secondary through-hole (65) is constant along its entire length. The secondary journal portion (29) of the drive shaft (25) is inserted through the secondary through-hole (65). The cylindrical portion (62) constitutes a journal bearing that supports the drive shaft (25).

[0052] A circumferential groove (66) is formed in the main body (61). The circumferential groove (66) is a circular groove that opens onto the upper surface of the main body (61) in Figure 3. The circumferential groove (66) surrounds the entire upper end of the secondary insertion hole (65) in Figure 3.

[0053] A second discharge port (64) is formed in the main body (61). The second discharge port (64) penetrates the main body (61) in the direction of its thickness. The second discharge port (64) is located to the left of the blade housing hole (77) in Figure 4B. Although not shown in the illustration, a discharge valve for opening and closing the second discharge port (64) is provided on the lower surface of the main body (61) in Figure 4B.

[0054] <Intermediate Plate> The intermediate plate (35) is sandwiched between the first cylinder (70) and the second cylinder (75). The intermediate plate (35) covers the lower end surface of the first cylinder (70) and the upper end surface of the second cylinder (75).

[0055] A central hole is formed in the middle of the intermediate plate (35), penetrating it in the thickness direction. The drive shaft (25) is inserted through the central hole of the intermediate plate (35).

[0056] <Laura> As shown in Figures 4A and 4B, the first roller (80) and the second roller (85) are each slightly thick cylindrical members.

[0057] The first roller (80) is housed in the first cylinder (70). The first eccentric portion (27a) of the drive shaft (25) is inserted through the first roller (80). The first roller (80) rotates eccentrically when driven by the drive shaft (25). In the compression mechanism (30), a first fluid chamber (31) is formed between the outer circumferential surface of the first roller (80) and the inner circumferential surface of the first cylinder (70).

[0058] The second roller (85) is housed in the second cylinder (75). The second eccentric portion (27b) of the drive shaft (25) is inserted through the second roller (85). The second roller (85) rotates eccentrically when driven by the drive shaft (25). In the compression mechanism (30), a second fluid chamber (32) is formed between the outer circumferential surface of the second roller (85) and the inner circumferential surface of the second cylinder (75).

[0059] <Bane> As shown in Figures 4A and 4B, each vane (81, 86) is a slightly thick rectangular plate-shaped member. The first vane (81) is formed integrally with the first roller (80). The second vane (86) is formed integrally with the second roller (85). Each vane (81, 86) extends radially outward from the outer surface of the corresponding roller (80, 85).

[0060] The first vane (81) fits into the blade housing hole (72) of the first cylinder (70). The first vane (81) divides the first fluid chamber (31) formed inside the first cylinder (70) into a first chamber on the intake side (first intake port (73) side) and a second chamber on the discharge side (first discharge port (44) side).

[0061] The second vane (86) fits into the blade housing hole (77) of the second cylinder (75). The second vane (86) divides the second fluid chamber (32) formed inside the second cylinder (75) into a first chamber on the intake side (second intake port (78)) and a second chamber on the discharge side (second discharge port (64)).

[0062] <Bush> As shown in Figures 4A and 4B, the bushes (82, 87) are small, plate-shaped members with flat front surfaces on opposite sides and an arcuate back surface on the back.

[0063] A pair of bushings (82) provided on the first cylinder (70) are positioned to sandwich the first vane (81), which is fitted into the blade housing hole (72) of the first cylinder (70), from both sides. The first vane (81), which is integrated with the first roller (80), is supported by the first cylinder (70) via these bushings (82) so as to be able to swing and move back and forth.

[0064] A pair of bushings (87) provided on the second cylinder (75) are positioned to sandwich the second vane (86), which is fitted into the blade housing hole (77) of the second cylinder (75), from both sides. The second vane (86), which is integrated with the second roller (85), is supported by the second cylinder (75) via these bushings (87) so as to be able to swing and move back and forth.

[0065] -Compressor operation- The operation of the compressor (10) will be explained.

[0066] When the electric motor (20) is energized, the rotor (22) rotates, and the rotor (22) drives the drive shaft (25). The drive shaft (25) rotates clockwise in Figures 4A and 4B. When the drive shaft (25) rotates, the first roller (80) and the second roller (85) are driven. As a result, in the compression mechanism (30), the gaseous refrigerant that has passed through the first suction pipe (19a) flows into the first chamber of the first fluid chamber (31), and the gaseous refrigerant that has passed through the second suction pipe (19b) flows into the first chamber of the second fluid chamber (32).

[0067] In the compression mechanism (30), the refrigerant compressed in the second chamber of the first fluid chamber (31) is discharged through the first discharge port (44) into the internal space of the casing (15), and the refrigerant compressed in the second chamber of the second fluid chamber (32) is discharged through the second discharge port (64) into the internal space of the casing (15). The gaseous refrigerant discharged from the compression mechanism (30) into the internal space of the casing (15) is discharged to the outside of the casing (15) through the discharge pipe (18).

[0068] -Shape of the boss- The shape of the boss portion (42) of the front head (40) will be explained in detail.

[0069] As shown in Figure 5, the boss portion (42) is formed in a cylindrical shape with a constriction in the axial middle. The side surface of the boss portion (42) shown in Figure 5 is curved towards the center of the boss portion (42). As described above, the diameter of the main insertion hole (45) is constant along the entire length of the main insertion hole (45). Therefore, the inner diameter of the boss portion (42) is constant along the entire length of the boss portion (42).

[0070] The boss portion (42) is divided into a base portion (52), an intermediate portion (53), and a protruding portion (51). In the boss portion (42), the base portion (52), the intermediate portion (53), and the protruding portion (51) are arranged in order from bottom to top in Figure 5.

[0071] <Protruding tip> The tip (51) is the portion of the boss (42) that includes the end on the motor (20) side (the upper end in Figure 5). The tip (51) is divided into a section with increased thickness (51a) and a section with constant thickness (51b). At the tip (51), the section with constant thickness (51b) is located closer to the motor (20) (upper side in Figure 5) than the section with increased thickness (51a).

[0072] The outer diameter of the thickened section (51a) increases continuously from bottom to top in Figure 5. On the other hand, the inner diameter of the boss section (42) remains constant along its entire length. Therefore, in the thickened section (51a), the thickness t1 of the protruding end (51) increases continuously from bottom to top in Figure 5. The thickened section (51a) is the first thickened section. In the thickened section (51a), the thickness t1 of the protruding end (51) is maximum at the upper end in Figure 5.

[0073] The outer diameter of the constant-thickness section (51b) is constant. On the other hand, the inner diameter of the boss section (42) is constant along the entire length of the boss section (42). Therefore, in the constant-thickness section (51b), the thickness t1 at the tip (51) is constant. The thickness of the constant-thickness section (51b) is equal to the maximum value t1_max of the thickness of the thickness-increasing section (51a).

[0074] <Proximal end> The base portion (52) is the part that includes the end of the boss portion (42) on the flat plate portion (41) side (the lower end in Figure 5).

[0075] The outer diameter of the base portion (52) increases continuously from top to bottom in Figure 5. On the other hand, the inner diameter of the boss portion (42) remains constant along the entire length of the boss portion (42). Therefore, the wall thickness t2 of the base portion (52) increases continuously from top to bottom in Figure 5. The entire base portion (52) is a wall thickness increase portion (52a). This wall thickness increase portion (52a) is a second wall thickness increase portion.

[0076] The wall thickness t2 of the base end portion (52) is maximum at the end on the flat plate portion (41) side (the lower end in Fig. 5). The maximum value t2_max of the wall thickness of the base end portion (52) is larger than the maximum value t1_max of the wall thickness of the protruding end portion (51) (t1_max<t2_max).

[0077] <Intermediate Portion> The intermediate portion (53) is a portion located between the base end portion (52) and the protruding end portion (51). The intermediate portion (53) is continuous with both the base end portion (52) and the protruding end portion (51).

[0078] The intermediate portion (53) is the portion having the smallest outer diameter in the boss portion (42). On the other hand, the inner diameter of the boss portion (42) is constant over the entire length of the boss portion (42). Therefore, the intermediate portion (53) is the portion having the smallest wall thickness in the boss portion (42).

[0079] The wall thickness t3 of the intermediate portion (53) is smaller than the wall thickness t1 of the protruding end portion (51) (t3<t1), and is smaller than the wall thickness t2 of the base end portion (52) (t3<t2). The ratio of the wall thickness t3 of the intermediate portion (53) to the maximum wall thickness t2_max of the base end portion (52) (t3 / t2_max) is desirably not less than 0.5 and not more than 0.75.

[0080] - Deformation of Boss Portion - During operation of the compressor (10), the rotor (22) of the electric motor (20) rotates, and the centrifugal force generated by the rotation of the rotor (22) acts on the drive shaft (25). Therefore, the drive shaft (25) bends such that the upper end portion in Fig. 2 is slightly displaced outward in the radial direction of the drive shaft (25). When the boss portion (42) is substantially not deformable, if the drive shaft (25) bends in this manner, the drive shaft (25) may come into contact with the vicinity of the upper end of the boss portion (42) in Fig. 2, and the drive shaft (25) may be damaged.

[0081] In this embodiment, the boss portion (42) is formed in a cylindrical shape that is constricted in the middle in the axial direction, and the wall thickness is thinnest at the middle portion (53). In other words, the wall thickness of the middle portion (53) is thinner than that of the base portion (52) and thinner than that of the protruding portion (51). Consequently, the rigidity of the middle portion (53) is lower than that of the base portion (52) and lower than that of the protruding portion (51). Therefore, when the drive shaft (25) bends during the operation of the compressor (10), the boss portion (42) deforms in the region including the middle portion (53), and the upper end of the boss portion (42) in Figure 5 is slightly displaced radially outward.

[0082] Thus, in the compression mechanism (30) of this embodiment, when the drive shaft (25) deflects during the operation of the compressor (10), the upper end of the boss portion (42) in Figure 5 is slightly displaced away from the drive shaft (25). Therefore, even when the drive shaft (25) comes into contact with the inner surface of the tip (51) of the boss portion (42), the load (contact pressure) acting on the contact portion between the drive shaft (25) and the tip (51) is kept low, and as a result, damage to the drive shaft (25) and the tip (51) is suppressed.

[0083] Furthermore, in the boss portion (42) of this embodiment, the thickness of the tip is greater than that of the intermediate portion, and therefore the rigidity of the tip (51) is higher than that of the intermediate portion (53). As a result, excessive displacement of the tip (51) is suppressed, and the reduction in the load that the journal bearing formed by the boss portion (42) can support is suppressed.

[0084] As described above, in the boss portion (42) of this embodiment, the ratio (t3 / t2_max) of the thickness t3 of the intermediate portion (53) to the maximum thickness t2_max of the base portion (52) is preferably 0.5 or more and 0.75 or less. If this ratio (t3 / t2_max) is less than 0.5, the rigidity of the boss portion (42) may become too low, and the load that the boss portion (42) can support may become too small. On the other hand, if this ratio (t3 / t2_max) is greater than 0.75, the displacement of the tip portion (51) of the boss portion (42) may become too small, and the deflected drive shaft (25) may come into contact with the boss portion (42). Therefore, by setting this ratio (t3 / t2_max) to 0.5 or more and 0.75 or less, it is possible to ensure that the boss portion (42) can support a load while suppressing damage to the drive shaft (25) and the boss portion (42).

[0085] -Modified Embodiments- The compressor (10) of the above embodiment may be modified as follows. Note that the following modifications may be combined or substituted as appropriate, as long as they do not impair the function of the compressor (10).

[0086] <First variation> In the compressor (10) of this embodiment, the boss portion (42) of the front head (40) may have the shape shown in Figure 6. Here, we will explain the differences between the boss portion (42) of this modified example and the boss portion (42) shown in Figure 5.

[0087] In the boss portion (42) of this modified example, the outer diameter of the increased wall thickness portion (51a) at the tip (51) increases in proportion to the distance from the lower end of the increased wall thickness portion (51a) in Figure 6. The side surface of the increased wall thickness portion (51a) shown in Figure 6 is straight.

[0088] In this modified example, the boss portion (42) has an intermediate portion (53) that extends over a predetermined length in the direction of the central axis of the boss portion (42). The outer diameter of the intermediate portion (53) is constant over its entire length. Therefore, the wall thickness t3 of the intermediate portion (53) in this modified example is constant over its entire length.

[0089] In the boss portion (42) of the present modified example, the outer diameter of the increased thickness portion (52a) of the base end portion (52) increases in proportion to the distance from the upper end of the increased thickness portion (52a) in FIG. 6. The side surface of the increased thickness portion (52a) shown in FIG. 6 is linear.

[0090] <Second Modified Example> In the compressor (10) of the present embodiment, the boss portion (42) of the front head (40) may have a shape as shown in FIG. 7. Here, differences of the boss portion (42) of the present modified example from the boss portion (42) shown in FIG. 5 will be described.

[0091] In the boss portion (42) of the present modified example, the base end portion (52) is divided into an increased thickness portion (52a) and a constant thickness portion (52b). In the base end portion (52), the constant thickness portion (52b) is located closer to the flat plate portion (41) (the lower side in FIG. 7) than the increased thickness portion (52a).

[0092] The outer diameter of the constant thickness portion (52b) is constant. Further, the inner diameter of the boss portion (42) is constant over the entire length of the boss portion (42). Accordingly, in the constant thickness portion (52b), the thickness t2 of the base end portion (52) is constant. The thickness of the constant thickness portion (52b) is equal to the maximum thickness value t2_max of the increased thickness portion (52a).

[0093] <Third Modified Example> In the compressor (10) of the present embodiment, the boss portion (42) of the front head (40) may have a shape as shown in FIG. 8. Here, differences of the boss portion (42) of the present modified example from the boss portion (42) shown in FIG. 6 will be described.

[0094] In the boss portion (42) of the present modified example, the outer diameter of the protruding end portion (51) is constant over the entire length of the protruding end portion (51). Accordingly, the thickness t1 of the protruding end portion (51) of the present modified example is constant over the entire length of the protruding end portion (51). The thickness t1 of the protruding end portion (51) is larger than the thickness t3 of the intermediate portion (t3<t1). Further, the thickness t1 of the protruding end portion (51) is smaller than the maximum thickness value t2_max of the base end portion (52) (t1<t2_max).

[0095] <Fourth Modification> In the compressor (10) of the present embodiment, the boss portion (42) of the front head (40) may have a shape as shown in Fig. 9. Here, differences between the boss portion (42) of the present modification and the boss portion (42) shown in Fig. 5 will be described.

[0096] In the boss portion (42) of the present modification, the outer diameter of the increased thickness portion (51a) of the protruding end portion (51) increases stepwise from bottom to top in Fig. 9. Accordingly, in the increased thickness portion (51a), the thickness t1 of the protruding end portion (51) increases stepwise from bottom to top in Fig. 9.

[0097] In the boss portion (42) of the present modification, the outer diameter of the increased thickness portion (52a) of the base end portion (52) increases stepwise from top to bottom in Fig. 9. Accordingly, in the increased thickness portion (52a), the thickness t2 of the base end portion (52) increases stepwise from top to bottom in Fig. 9.

[0098] <Fifth Modification> In the compressor (10) of the present embodiment, the boss portion (42) of the front head (40) may have a shape as shown in Fig. 10. Here, differences between the boss portion (42) of the present modification and the boss portion (42) shown in Fig. 8 will be described.

[0099] In the boss portion (42) of the present modification, the outer diameter of the base end portion (52) is constant over the entire length of the base end portion (52). Accordingly, the thickness t2 of the base end portion (52) of the present modification is constant over the entire length of the base end portion (52). The thickness t2 of the base end portion (52) is greater than the thickness t3 of the intermediate portion (t3<t2). Further, the thickness t2 of the base end portion (52) is greater than the thickness t1 of the protruding end portion (51) (t1<t2).

[0100] <Sixth Modification> The compressor (10) in this embodiment may be a rolling piston type rotary compressor. In this case, the compression mechanism (30) of the compressor (10) has rollers (80, 85) and vanes (81, 86) formed separately. The tips of the vanes (81, 86) are pressed against the sides of the rollers (80, 85). When the rollers (80, 85) rotate eccentrically, the vanes (81, 86) move back and forth radially in the cylinder (70, 75).

[0101] Furthermore, the compressor (10) in this embodiment may be a hinge vane type rotary compressor. In this case, the compression mechanism (30) of the compressor (10) has rollers (80, 85) and vanes (81, 86) formed separately. The tips of the vanes (81, 86) are connected to the rollers (80, 85). The vanes (81, 86) are displaceable relative to the rollers (80, 85). When the rollers (80, 85) rotate eccentrically, the vanes (81, 86) move back and forth radially in the cylinder (70, 75).

[0102] Furthermore, the compressor (10) in this embodiment may be a compressor of a type other than a rotary compressor (for example, a scroll compressor).

[0103] While embodiments and modifications have been described above, it will be understood that various changes in form and details are possible without departing from the spirit and scope of the claims. Furthermore, elements of the embodiments, modifications, and other embodiments described above may be combined or substituted as appropriate. In addition, the designations "First," "Second," etc. in the specification and claims are used to distinguish the phrases to which these designations are given, and do not limit the number or order of such phrases. [Industrial applicability]

[0104] As described above, this disclosure is useful for compressors and refrigeration cycle systems. [Explanation of Symbols]

[0105] 10 Compressor 20 Electric motor 25 Drive shaft 30 Compression mechanism 31 1st fluid chamber (fluid chamber) 40 Front Head 41 Flat plate part 42 Boss Section 51. Promontory 51a First thickness increase section (thickness increase section) 52 Proximal end 52a Second thickness increase section (thickness increase section) 53 Middle section 70. First cylinder (cylinder) 80. First Laura (Laura) 81. First Bane (Bane) 100 Air conditioners (refrigeration cycle devices) 110 Refrigerant Circuit

Claims

1. A compressor (10) comprising a compression mechanism (30) for drawing in and compressing a fluid, a drive shaft (25) for driving the compression mechanism (30), and an electric motor (20) having a rotor (22) attached to the drive shaft (25), The above-mentioned compression mechanism (30) is provided with a cylindrical boss portion (42) that protrudes toward the electric motor (20), and the boss portion (42) constitutes a sliding bearing that supports the drive shaft (25). The boss portion (42) described above is The protruding end (51) including one end of the electric motor (20) mentioned above, The base end (52) includes the other end opposite to the above-mentioned protruding end (51), It is located between the base end (52) and the protruding end (51) and is divided into an intermediate portion (53) which is thinner than the protruding end (51) and the base end (52). Compressor.

2. The aforementioned protruding portion (51) includes a thickness-increasing portion (51a) in which the thickness gradually increases from the intermediate portion (53) toward one end of the boss portion (42). The compressor according to claim 1.

3. The base portion (52) includes a thickness-increasing portion (52a) in which the thickness gradually increases from the intermediate portion (53) toward the other end of the boss portion (42). The compressor according to claim 1.

4. The above-mentioned protruding portion (51) is provided with a first thickness-increasing portion (51a) in which the thickness gradually increases from the above-mentioned intermediate portion (53) toward one end of the above-mentioned boss portion (42), The base portion (52) is provided with a second thickness-increasing portion (52a) in which the thickness gradually increases from the intermediate portion (53) toward the other end of the boss portion (42), The maximum thickness of the base portion (52) is greater than the maximum thickness of the protruding portion (51). The compressor according to claim 1.

5. The above compression mechanism (30) is Cylinder (70) and A cylindrical roller (80) is housed in the cylinder (70) and rotates eccentrically when driven by the drive shaft (25), A vane (81) partitions the fluid chamber (31) formed between the cylinder (70) and the roller (80), The system includes a front head (40) positioned closer to the electric motor (20) than the cylinder (70), The front head (40) comprises the boss portion (42) and a flat plate portion (41) that covers one end face of the cylinder (70). The boss portion (42) protrudes from the flat plate portion (41) toward the electric motor (20). A compressor according to any one of claims 1 to 4.

6. A refrigerant circuit (110) is provided with one of the compressors (10) according to claims 1 to 4, In the above refrigerant circuit (110), the refrigerant is circulated to perform a refrigeration cycle. Refrigeration cycle device.

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