Rotary compressor and method for manufacturing rotary compressor

Abstract

Provided is a rotary compressor in which a rotary compression unit (6) has: a piston rotor; a cylinder housing the piston rotor; an upper bearing (4A) and a lower bearing disposed so as to sandwich the cylinder and form a compression chamber (60A) for accommodating the piston rotor; and a discharge valve (64) which is attached to the upper bearing (4A) and which opens and closes a discharge hole (4Aa) through which the refrigerant compressed in the compression chamber (60A) is discharged, in which a recess (4Ad) for accommodating the discharge valve (64) is formed in a facing surface (4Ab) of the upper bearing (4A) facing the electric motor, and the discharge hole (4Aa) penetrating along the rotational axis is formed in the bottom (4Ad1) of the recess (4Ad). An inclined portion (4Ad2) is formed in the recess (4Ad), the height of the inclined portion (4Ad2) from the bottom portion (4Ad1) to the facing surface (4Ab) decreasing as the distance from the discharge hole (4Aa) increases.

Description

Technical Field

[0001] The invention relates to a rotary compressor and a method for manufacturing the rotary compressor. Background Art

[0002] A rotary compressor is known that compresses refrigerant by a rotor eccentrically arranged relative to a rotating shaft in a compression chamber (for example, refer to Patent Document 1). The rotary compressor disclosed in Patent Document 1 is a rotary compressor that has an upper surface of an upper bearing hollowed out to form a thin-walled portion, and a discharge port that penetrates toward a cylinder chamber is formed in the thin-walled portion. The rotary compressor disclosed in Patent Document 1 reduces the volume by shortening the discharge port, thereby achieving high pump efficiency.

[0003] Previous technical literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 11-132178 Summary of the invention

[0006] Technical issues to be solved by the invention

[0007] However, in the rotary compressor disclosed in Patent Document 1, a discharge port is provided at the bottom of a recess formed by digging out the upper surface of the upper bearing, so the refrigerant gas discharged from the discharge port may collide with the end surface of the recess and generate a large pressure loss. In particular, in a small rotary compressor (for example, a housing inner diameter of Φ95 [mm] or less), the pressure loss becomes significant because the distance from the discharge port to the end surface of the recess is short.

[0008] The present invention has been made in view of such circumstances, and an object of the present invention is to provide a rotary compressor and a method for manufacturing the rotary compressor that can suppress the pressure loss of the refrigerant discharged from a discharge valve accommodated in a recess formed in a bearing.

[0009] Means for solving technical problems

[0010] In order to solve the above-mentioned problems, the rotary compressor of the present invention comprises: a housing having a cylindrical portion extending along an axis and in a vertical direction; a compression portion accommodated in the housing and compressing a refrigerant; and a drive portion accommodated in the housing and driving the compression portion by rotating a rotating shaft extending along the axis, the compression portion comprising: a piston rotor fixed to the rotating shaft and rotating eccentrically with respect to the axis; a cylinder body accommodating the piston rotor; a pair of bearings supporting the rotating shaft rotatably around the axis and arranged to sandwich the cylinder body along the axis to form a compression chamber accommodating the piston rotor; and a discharge valve mounted on one of the pair of bearings and opening and closing a discharge hole for discharging the refrigerant compressed in the compression chamber, a recess for accommodating the discharge valve being formed on an opposing surface of one of the pair of bearings opposing the drive portion, the discharge hole penetrating along the axis being formed at the bottom of the recess, and an inclined portion whose height from the bottom to the opposing surface becomes lower as the distance from the discharge hole becomes longer is formed in the recess.

[0011] Furthermore, in the manufacturing method of the rotary compressor of the present invention, the rotary compressor comprises: a shell having a cylindrical portion extending along the axis and in the vertical direction; a compression portion, which is accommodated in the shell and compresses the refrigerant; and a driving portion, which is accommodated in the shell and drives the compression portion by rotating a rotating shaft extending along the axis, the compression portion comprising: a piston rotor, which is fixed to the rotating shaft and rotates eccentrically relative to the axis; a cylinder body, which accommodates the piston rotor; a pair of bearings, which support the rotating shaft rotatably around the axis and are arranged to clamp the rotating shaft along the axis. The cylinder body forms a compression chamber for accommodating the piston rotor; and a discharge valve is installed on one of the pair of bearings and opens and closes a discharge hole for discharging the refrigerant compressed in the compression chamber. The manufacturing method of the rotary compressor includes the following steps: forming a recess for accommodating the discharge valve by cutting an opposing surface of one of the pair of bearings that is opposite to the driving part; and forming the discharge hole passing through the axis line at the bottom of the recess, and in the step of forming the recess, forming an inclined portion whose height from the bottom to the opposing surface becomes lower as the distance from the discharge hole becomes longer.

[0012] Effects of the Invention

[0013] According to the present invention, it is possible to provide a rotary compressor and a method for manufacturing the rotary compressor that can suppress the pressure loss of the refrigerant discharged from the discharge valve accommodated in the recess formed in the bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a longitudinal cross-sectional view showing a rotary compressor according to one embodiment of the present invention.

[0015] Figure 2 Yes means Figure 1 A side view of a rotary compressor installed on a mounting surface.

[0016] Figure 3 This is a top view of the upper bearing of the rotary compression unit viewed from above along the rotation axis.

[0017] Figure 4 yes Figure 3 A cross-sectional view of the rotary compression portion taken along the arrow AA is shown.

[0018] Figure 5 yes Figure 3 A partial enlarged view of the vicinity of the discharge hole of the rotary compression section shown.

[0019] Figure 6 This is a top view of the upper bearing of the rotary compression unit of the first modified example viewed from above along the rotation axis.

[0020] Figure 7 yes Figure 6 A cross-sectional view of the rotary compression portion taken along the arrow BB is shown.

[0021] Figure 8 This is a plan view of the upper bearing of the rotary compression portion of the second modified example as viewed from above along the rotation axis.

[0022] Fig. 9 yes Figure 8 A cross-sectional view of the rotary compression portion as viewed along the CC direction is shown. DETAILED DESCRIPTION

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0024] like Figure 1 As shown, the rotary compressor 1 according to the present embodiment is a hermetic electric rotary compressor used in, for example, an air conditioner or a refrigeration device. The rotary compressor 1 includes a compressor body 10 and an accumulator 12. The accumulator 12 is connected to the compressor body 10 via a suction pipe 11.

[0025] The compressor body 10 includes a substantially cylindrical housing 2, a rotating shaft 3, an electric motor (driving unit) 5, and a rotary compression unit 6. The rotating axis CL of the rotating shaft 3 coincides with the central axis of the housing 2. The rotating shaft 3 is arranged so as to extend in the vertical direction and rotates around the rotating axis CL in the housing 2.

[0026] The housing 2 is a closed type and extends in the vertical direction. The housing 2 includes a main body (cylindrical part) 21 in a cylindrical shape extending along the rotation axis CL and in the vertical direction VD, and an upper cover 22 and a lower cover 23 that close the upper and lower openings of the main body 21 .

[0027] A plurality of legs 7 are fixed below the main body 21. The legs 7 are arranged at predetermined angles in the circumferential direction of the main body 21. Figure 2 As shown, each leg portion 7 is fixed to the installation surface FL via a vibration-isolating rubber 8 .

[0028] The housing 2 has an opening 24 formed at a position in the side wall lower portion facing the outer peripheral surface of the cylinder 60. The cylinder 60 has a suction port 25 formed at a position facing the opening 24 and communicating with a predetermined position in the cylinder.

[0029] An oil reservoir for storing lubricating oil is formed at the bottom of the housing 2. The liquid level of the oil reservoir when the oil is initially sealed is located above the rotary compressor 6. Thus, the rotary compressor 6 is driven in the oil reservoir.

[0030] The upper cover 22 is provided with a discharge pipe 13 and a terminal block 30. The discharge pipe 13 penetrates the upper cover 22 in the thickness direction, with the lower portion arranged inside the housing 2 and the upper portion arranged outside the housing 2. The discharge pipe 13 discharges the compressed refrigerant to the outside of the housing 2. The terminal block 30 is provided with three power supply terminals 31 for supplying power to the electric motor 5. Three-phase power is supplied to the power supply terminals 31 from an inverter device (not shown).

[0031] The accumulator 12 is used to separate the refrigerant into gas and liquid before supplying it to the compressor body 10. The accumulator 12 is set to be roughly cylindrical in shape and is fixed to the outer peripheral surface of the shell 2 via a bracket 14. An inlet pipe 15 for introducing refrigerant guided from an evaporator not shown in the figure is provided at the upper part of the accumulator 12. A suction pipe 11 for sucking the internal refrigerant into the compressor body 10 is connected to the accumulator 12. The suction pipe 11 is connected to the suction port 25 through the opening 24 of the shell 2. The accumulator 12 supplies the gas phase refrigerant to the rotary compression part 6 via the suction pipe 11.

[0032] The electric motor 5 is accommodated in the central part of the housing 2 in the vertical direction. The electric motor 5 includes a rotor 51 and a stator 52. The rotor 51 is fixed to the outer peripheral surface of the rotating shaft 3 and is arranged above the rotary compression unit 6. The stator 52 is arranged to surround the outer peripheral surface of the rotor 51 and is fixed to the inner surface 21a of the main body 21 of the housing 2.

[0033] Electric power is supplied from each power supply terminal 31 to the stator 52 via the wiring 32. The electric motor 5 rotates the rotary shaft 3 by the electric power supplied from the power supply terminal 31, thereby driving the rotary compression unit 6.

[0034] The rotary compression unit 6 is a device that is accommodated in the shell 2 and compresses the refrigerant. The rotary compression unit 6 is arranged in a state of being clamped from above and below by the upper bearing 4A and the lower bearing 4B. The upper bearing 4A and the lower bearing 4B are respectively formed of metal materials and fixed to the cylinder 60 constituting the rotary compression unit 6 by bolts 61. In addition, the rotating shaft 3 is rotatably supported around the rotation axis CL by the upper bearing 4A and the lower bearing 4B.

[0035] The rotary compression unit 6 is disposed at the bottom of the housing 2 below the electric motor 5. The rotary compression unit 6 includes an upper bearing 4A, a lower bearing 4B, a cylinder 60, an eccentric shaft 62, a piston rotor 63, and a discharge valve 64 (see FIG. Figure 3 ).

[0036] The cylinder 60 is formed with a compression chamber 60A, an intake hole 60B, and a discharge hole (not shown). The compression chamber 60A is formed inside the cylinder 60. The piston rotor 63 is accommodated in the compression chamber 60A. The upper bearing 4A and the lower bearing 4B are arranged to sandwich the cylinder 60 along the rotation axis CL to form the compression chamber 60A for accommodating the piston rotor 63.

[0037] The rotary compression section 6 is fixed to the inner surface 21a of the main body 21 of the housing 2. Specifically, the upper bearing 4A of the clamping cylinder 60 is fixed to the inner surface 21a of the main body 21 of the housing 2. The upper bearing 4A is fixed by plug welding at multiple locations in the circumferential direction of the housing 2. In addition, heat press fitting, shrink fitting, etc. can also be used instead of plug welding.

[0038] The eccentric shaft portion 62 is provided at the lower end portion of the rotating shaft 3 , and is provided inside the piston rotor 63 in a state of being offset (eccentric) in a direction orthogonal to the central axis of the rotating shaft 3 .

[0039] The piston rotor 63 is arranged inside the cylinder 60 in a cylindrical shape with an outer diameter smaller than the inner diameter of the cylinder 60 and is fixed to the outer periphery of the eccentric shaft portion 62. The piston rotor 63 rotates eccentrically with respect to the rotation axis CL as the rotary shaft 3 rotates.

[0040] The suction hole 60B is a hole for guiding the refrigerant into the cylinder 60, and is formed in a direction perpendicular to the rotation axis CL. Figure 4 ) The high-pressure refrigerant discharged is guided into the space formed between the discharge cover 65 and the upper bearing 4A, and then guided into the internal space of the shell 2 through the discharge hole (not shown) provided in the discharge cover 65.

[0041] The rotary compressor 1 operates as follows. The refrigerant guided from the evaporator (not shown) is taken into the accumulator 12 via the inlet pipe 15. The refrigerant is separated into gas and liquid in the accumulator 12, and the gas phase is guided to the rotary compressor 6 via the suction pipe 11. In the rotary compressor 6, the refrigerant is guided to the compression chamber 60A via the suction hole 60B.

[0042] Then, the volume of the compression chamber 60A is gradually reduced and the refrigerant is compressed by the eccentric rotation of the piston rotor 63. The compressed refrigerant passes through the space in the discharge cover 65 through the discharge hole 4Aa and is guided to the internal space of the shell 2. The refrigerant discharged into the internal space of the shell 2 is guided from the discharge pipe 13 provided at the upper part of the shell 2 to the condenser (not shown).

[0043] Next, refer to Figures 3 to 5 , the upper bearing 4A and the discharge valve 64 of the rotary compression section 6 will be described. Figure 3 It is a plan view of the upper bearing 4A of the rotary compression section 6 as viewed from above along the rotation axis CL.

[0044] Figure 4 yes Figure 3 The sectional view of the rotary compression portion 6 taken along the line AA is shown. Figure 3 and Figure 4 The state where the discharge cover 65 is removed from the upper bearing 4A is shown. Figure 5 yes Figure 3 A partial enlarged view of the vicinity of the discharge hole 4Aa of the rotary compression section 6 is shown.

[0045] like Figure 3 and Figure 4 As shown, a discharge valve 64 is attached to the upper bearing 4A. The discharge valve 64 is a device that opens and closes the discharge hole 4Aa for discharging the refrigerant compressed in the compression chamber 60A. The discharge valve 64 includes a valve element 64a, a retainer 64b, and a fastening bolt 64c.

[0046] The valve core 64a is a plate-shaped member having a biasing force to close the discharge hole 4Aa when the pressure of the refrigerant in the compression chamber 60A is below a predetermined pressure. The base end 64a1 of the valve core 64a is fixed to the position of the fastening hole 4Ac of the upper bearing 4A by a fastening bolt 64c. The front end 64a2 of the valve core 64a is arranged at the discharge hole 4Aa to close the discharge hole 4Aa.

[0047] A recess 4Ad for accommodating the discharge valve 64 is formed on the upper bearing 4A's surface 4Ab facing the electric motor 5. A discharge hole 4Aa is formed at a bottom 4Ad1, which is a lower end in the vertical direction VD of the recess 4Ad and passes through along the rotation axis CL in the vertical direction VD.

[0048] The recess 4Ad has an inclined portion 4Ad2 whose height in the vertical direction VD from the bottom 4Ad1 to the facing surface 4Ab becomes lower as the distance in the horizontal direction HD from the discharge hole 4Aa becomes longer. The inclined portion 4Ad2 is formed so that the height in the vertical direction VD from the bottom 4Ad1 to the facing surface 4Ab gradually becomes lower along the extending direction (the same direction as the horizontal direction HD) from the base end portion 64a1 of the valve element 64a of the discharge valve 64 toward the front end portion 64a2.

[0049] like Figure 3 As shown, the inclined portion 4Ad2 has a first recess 4Ad21 and a second recess 4Ad22 when the facing surface 4Ab of the upper bearing 4A is viewed along the rotation axis CL. The first recess 4Ad21 is a circular portion having a diameter (first diameter) D1 with the discharge hole 4Aa as the center. The second recess 4Ad22 is a portion having an axis Z2 (reference axis Z2) separated from the discharge hole 4Aa. Figure 5 ) is a portion formed in a circle having a diameter (second diameter) D2 at its center. The second recess 4Ad22 is arranged to overlap with the first recess 4Ad21.

[0050] like Figure 5 As shown by the middle arrow, if the pressure of the refrigerant in the compression chamber 60A exceeds the predetermined pressure and the front end 64a2 of the valve core 64a is separated from the discharge hole 4Aa, the discharge valve 64 becomes open, and the refrigerant flows radially from the discharge hole 4Aa in the horizontal direction HD. The refrigerant discharged from the discharge hole 4Aa collides with the end of the first recess 4Ad21 (from the axis Z1, the position of D1 / 2), and is guided to the upper side of the vertical direction VD.

[0051] The refrigerant having passed through the end of the first recess 4Ad21 further flows radially in the horizontal direction HD from the discharge hole 4Aa, collides with the end of the second recess 4Ad22, and is guided upward in the vertical direction VD. The refrigerant guided upward in the vertical direction VD and reaching the facing surface 4Ab of the upper bearing 4A is guided to the internal space of the housing 2 via the discharge hole (not shown) provided in the discharge cover 65.

[0052] It is preferable that the diameter D1 of the first recessed portion 4Ad21 and the diameter D2 of the second recessed portion 4Ad22 satisfy the following formula (1).

[0053] D1=D2 (1)

[0054] Furthermore, the diameter D1 and the diameter D2 can be set so as to satisfy the following formula (2).

[0055] D1 <D2(2)

[0056] like Figure 4As shown, the height (second height) H2 from the bottom 4Ad1 to the facing surface 4Ab in the vertical direction VD of the second recess 4Ad22 is lower than the height (first height) H1 from the bottom 4Ad1 to the facing surface 4Ab in the vertical direction VD of the first recess 4Ad21. The height H1 and the height H2 are preferably set to have a relationship of, for example, the following formula (3).

[0057] 0<(H1-H2) / H1≤0.5(3)

[0058] like Figure 4 As shown, the discharge hole 4Aa is a hole formed in a circular shape with the axis Z1 parallel to the rotation axis CL as the center in a plan view, and has a diameter D0. The discharge hole 4Aa and the first recess 4Ad21 are each formed in a circular shape with the axis Z1 as the center. The diameter D1 of the first recess 4Ad21 and the diameter D0 of the discharge hole 4Aa are preferably set to the relationship of the following formula (4).

[0059] D1≥2·D0(4)

[0060] Figures 3 to 5 The rotary compression section 6 shown is a mode in which the inclined portion 4Ad2 has the first recess 4Ad21 and the second recess 4Ad22 in the order of the shorter distance from the discharge hole 4Aa, but other modes are also possible. For example, as in the rotary compression section 6A of the first modified example, the inclined portion 4Ad2 may have the first recess 4Ad21, the second recess 4Ad22, and the third recess 4Ad23 in the order of the shorter distance from the discharge hole 4Aa.

[0061] Figure 6 This is a plan view of an upper bearing 4A of a rotary compression section 6A according to a first modified example as viewed from above along the rotation axis CL. Figure 7 yes Figure 6 The rotary compression section 6A is shown in a cross-sectional view taken along the line BB.

[0062] like Figure 6 As shown, the inclined portion 4Ad2 has a first recess 4Ad21, a second recess 4Ad22, and a third recess 4Ad23 when the facing surface 4Ab of the upper bearing 4A is viewed along the rotation axis CL. The third recess 4Ad23 is a circular portion having a diameter (third diameter) D3 centered at a position separated from the discharge hole 4Aa.

[0063] It is preferable that the diameter D1 of the first recess 4Ad21 , the diameter D2 of the second recess 4Ad22 , and the diameter D3 of the third recess 4Ad23 satisfy the following formula (5).

[0064] D1=D2=D3(5)

[0065] Furthermore, the diameter D1, the diameter D2, and the diameter D3 may be set so as to satisfy the following formula (6).

[0066] D1 <D2<D3(6)

[0067] like Figure 7 As shown, the height H2 from the bottom 4Ad1 to the facing surface 4Ab in the vertical direction VD of the second recess 4Ad22 is lower than the height H1 from the bottom 4Ad1 to the facing surface 4Ab in the vertical direction VD of the second recess 4Ad22. Furthermore, the height H3 from the bottom 4Ad1 to the facing surface 4Ab in the vertical direction VD of the third recess 4Ad23 (third height) is lower than the height H2 of the second recess 4Ad22.

[0068] It is preferable that the height H1, the height H2, and the height H3 are set to have a relationship represented by the following formula (7), for example.

[0069] (H1-H2)<(H2-H3)(7)

[0070] That is, it is preferable to make the difference between the height H2 and the height H3 larger than the difference between the height H1 and the height H2 so that the height difference increases as the distance from the discharge hole 4Aa increases. This is because if the height difference is large at a position short from the discharge hole 4Aa, the pressure loss when the refrigerant collides with the height difference becomes too large, and thus such excessive pressure loss is prevented from occurring.

[0071] Figures 3 to 5 The rotary compression section 6 shown in the figure is a mode in which the inclined portion 4Ad2 has a first recess 4Ad21 and a second recess 4Ad22 in the order of the shortest distance from the discharge hole 4Aa, but other modes are also possible. Fig. 9 As in the rotary compression section 6B of the second modified example shown, the inclined portion 4Ad2 may have an inclined shape in which the height H from the bottom 4Ad1 to the facing surface 4Ab in the vertical direction VD gradually decreases as the distance from the discharge hole 4Aa increases.

[0072] Figure 8 This is a plan view of an upper bearing 4A of a rotary compression section 6B according to a second modification example as viewed from above along the rotation axis CL. Fig. 9 yes Figure 8 The cross-sectional view of the rotary compression portion 6B taken along the line CC is shown.

[0073] like Fig. 9As shown, the inclined portion 4Ad2 has an inclined shape in which the height H from the bottom 4Ad1 to the facing surface 4Ab in the vertical direction VD gradually decreases as the distance from the discharge hole 4Aa increases. When the pressure of the refrigerant in the compression chamber 60A exceeds a predetermined pressure and the front end 64a2 of the valve core 64a is separated from the discharge hole 4Aa, the discharge valve 64 becomes open, and the refrigerant flows radially from the discharge hole 4Aa in the horizontal direction HD. The refrigerant discharged from the discharge hole 4Aa is guided to the upper side in the vertical direction VD along the shape of the inclined portion 4Ad2.

[0074] Next, a method for manufacturing the rotary compressor 1 of the present embodiment will be described. Hereinafter, a step of forming the recess 4Ad and the discharge hole 4Aa in the upper bearing 4A in the method for manufacturing the rotary compressor 1 will be described, and descriptions of other steps will be omitted.

[0075] The worker forms a recessed portion 4Ad by bringing a drill (not shown) into contact with the facing surface 4Ab of the upper bearing 4A where the recessed portion 4Ad is not formed and cutting the facing surface 4Ab. Figure 5 The worker forms the first concave portion 4Ad21 by countersinking, aligning the center of the drill with the axis Z1, and forming the first concave portion 4Ad21 with a diameter D1 centered on the axis Z1. The worker moves the drill so that the height from the bottom 4Ad1 to the facing surface 4Ab becomes H1.

[0076] Next, when forming the second recessed portion 4Ad22 by countersinking, the worker makes the center of the drill coincide with the axis Z2, and forms the second recessed portion 4Ad22 with a diameter D2 centered on the axis Z2. The worker moves the drill so that the height from the bottom 4Ad1 to the facing surface 4Ab becomes H2. In addition, when the diameter D2 is made consistent with the diameter D1, the worker forms the second recessed portion 4Ad22 without changing the drill after forming the first recessed portion 4Ad21. Thus, the worker forms the inclined portion 4Ad2 having the first recessed portion 4Ad21 and the second recessed portion 4Ad22.

[0077] Next, the worker uses a drill to cut and form a discharge hole 4Aa penetrating along the axis Z1 at the bottom 4Ad1 of the recess 4Ad formed on the facing surface 4Ab of the upper bearing 4A. Then, the worker fastens the fastening bolt 64c to the fastening hole 4Ac of the upper bearing 4A to fix the discharge valve 64 at the position of the fastening hole 4Ac of the upper bearing 4A.

[0078] The rotary compressor 1 according to the present embodiment described above achieves the following operations and effects.

[0079] According to the rotary compressor 1 of this embodiment, the rotary compressor 6 is driven by the electric motor 5 to rotate the rotary shaft 3. The rotary compressor 6 compresses the refrigerant by rotating the piston rotor 63 in the compression chamber 60A formed by the upper bearing 4A and the lower bearing 4B sandwiching the cylinder 60, thereby gradually reducing the volume of the compression chamber 60A. The compressed refrigerant is guided from the discharge hole 4Aa to the internal space of the housing 2 where the electric motor 5 is arranged via the discharge valve 64.

[0080] According to the rotary compressor 1 of the present embodiment, the discharge valve 64 is accommodated in the recess 4Ad formed in the opposing surface 4Ab opposed to the electric motor 5, and the compressed refrigerant is discharged from the discharge valve 64 toward the recess 4Ad. Since the recess 4Ad is formed with an inclined portion, the flow direction of the refrigerant discharged from the discharge valve toward the recess is changed in a manner that approaches the opposing surface from the bottom in stages. Therefore, compared with the case where the flow direction of the refrigerant discharged from the discharge valve toward the recess is changed by only one stage, the pressure loss of the refrigerant can be suppressed.

[0081] According to the rotary compressor 1 of this embodiment, since the inclined portion 4Ad2 is formed along the extension direction from the base end portion toward the front end portion of the discharge valve 64, the flow direction of the refrigerant can be changed in a manner that gradually approaches the opposing surface 4Ab from the bottom 4Ad1 along the direction in which the discharge valve 64 is opened to guide the refrigerant, that is, the extension direction.

[0082] Furthermore, according to the rotary compressor 1 of the present embodiment, the inclined portion 4Ad2 has the first recess 4Ad21 and the second recess 4Ad22, and the height H2 of the second recess 4Ad22 from the bottom 4Ad1 to the opposing surface 4Ab is lower than the height H1 of the first recess 4Ad21 from the bottom 4Ad1 to the opposing surface 4Ab. Therefore, the flow direction of the refrigerant discharged from the discharge valve 64 toward the recess 4Ad is changed in at least two stages, that is, the end of the first recess 4Ad21 and the end of the second recess 4Ad22, so as to approach the opposing surface 4Ab from the bottom 4Ad1. Therefore, compared with the case where the flow direction of the refrigerant discharged from the discharge valve 64 toward the recess 4Ad is changed only in one stage, that is, at the end of the recess 4Ad, the pressure loss of the refrigerant can be further suppressed.

[0083] According to the rotary compressor 1 of this embodiment, by setting the diameter D1 of the first recess 4Ad21 to be more than twice the diameter D0 of the discharge hole 4Aa, it is possible to prevent excessive pressure loss caused by the refrigerant discharged from the discharge hole 4Aa colliding with the recess 4Ad at a position that does not meet twice the diameter D0 of the discharge hole 4Aa.

[0084] According to the rotary compressor 1 of this embodiment, by making the diameter D2 of the second recess 4Ad22 the same as the diameter D1 of the first recess 4Ad21, the same cutting tool can be used for processing when forming the first recess 4Ad21 and the second recess 4Ad22 on the opposing surface 4Ab of the upper bearing 4A.

[0085] According to the rotary compressor 1 of this embodiment, by making the diameter D2 of the second recess 4Ad22 larger than the diameter D1 of the first recess 4Ad21, the pressure loss when the refrigerant collides with the end surface of the second recess 4Ad22 can be reduced compared with the case where the diameter D2 is the same as the diameter D1.

[0086] According to the manufacturing method of the rotary compressor 1 of the present embodiment, in the process of forming the recess 4Ad, the opposing surface 4Ab opposed to the upper bearing 4A is cut to form the inclined portion 4Ad2 whose height from the bottom 4Ad1 to the opposing surface 4Ab decreases as the distance from the discharge hole 4Aa increases. Since the recess 4Ad having the inclined portion 4Ad2 is formed by cutting, a bearing having a smaller outer diameter (for example, Φ95 [mm] or less) can be easily manufactured compared to the case where the upper bearing 4A having the recess 4Ad is formed by casting.

[0087] According to the rotary compressor 1 manufactured by the manufacturing method of the present embodiment, the discharge valve 64 is accommodated in the recess 4Ad formed in the opposing surface 4Ab opposed to the electric motor 5, and the compressed refrigerant is discharged from the discharge valve 64 toward the recess 4Ad. Since the inclined portion 4Ad2 is formed in the recess 4Ad, the flow direction of the refrigerant discharged from the discharge valve 64 toward the recess 4Ad is changed in a manner that it approaches the opposing surface 4Ab from the bottom 4Ad1 in stages. Therefore, compared with the case where the flow direction of the refrigerant discharged from the discharge valve 64 toward the recess 4Ad is changed only in one stage, the pressure loss of the refrigerant can be suppressed.

[0088] According to the manufacturing method of the rotary compressor 1 of the present embodiment, the first recess 4Ad21 and the second recess 4Ad22 are formed as the inclined portion 4Ad2 by cutting the opposing surface 4Ab, and the rotary compressor 1 is manufactured in which the height H2 from the bottom 4Ad1 to the opposing surface 4Ab of the second recess 4Ad22 is lower than the height H1 from the bottom 4Ad1 to the opposing surface 4Ab of the first recess 4Ad21. Therefore, the flow direction of the refrigerant discharged from the discharge valve 64 toward the recess 4Ad is changed in at least two stages, that is, the end of the first recess 4Ad21 and the end of the second recess 4Ad22, so as to approach the opposing surface 4Ab from the bottom 4Ad1. Therefore, compared with the case where the flow direction of the refrigerant discharged from the discharge valve 64 toward the recess 4Ad is changed only in one stage, that is, at the end of the recess 4Ad, the pressure loss of the refrigerant can be further suppressed.

[0089] According to the manufacturing method of the rotary compressor 1 of this embodiment, since the diameter D2 of the second recess 4Ad22 is the same as the diameter D1 of the first recess 4Ad21, the same cutting tool can be used for processing when cutting the opposing surface 4Ab of the upper bearing 4A to form the first recess 4Ad21 and the second recess 4Ad22.

[0090] The rotary compressor (1) described in each of the above-described embodiments can be understood, for example, as follows.

[0091] The rotary compressor according to the first aspect of the present invention comprises: a shell (2) having a cylindrical portion extending along an axis and in a vertical direction; a compression portion (6) accommodated in the shell and compressing a refrigerant; and a drive portion (5) accommodated in the shell and driving the compression portion by rotating a rotating shaft (3) extending along the axis, the compression portion comprising: a piston rotor (63) fixed to the rotating shaft and rotating eccentrically relative to the axis; a cylinder block (60) accommodating the piston rotor; and a pair of bearings (4A, 4B) supporting the rotating shaft rotatably around the axis and arranged to clamp the rotating shaft along the axis. The cylinder body is supported to form a compression chamber (60A) for accommodating the piston rotor; and a discharge valve (64) is installed on one of the pair of bearings (4A) and opens and closes a discharge hole (4Aa) for discharging the refrigerant compressed in the compression chamber. A recess (4Ad) for accommodating the discharge valve is formed on an opposing surface of one of the pair of bearings (4A) opposite to the driving portion, and the discharge hole penetrating along the axis is formed at the bottom (4Ad1) of the recess, and an inclined portion (4Ad2) is formed in the recess, the height of which decreases from the bottom to the opposing surface as the distance from the discharge hole increases.

[0092] According to the rotary compressor involved in the first aspect of the present invention, the driving unit rotates the rotating shaft to drive the compression unit. The compression unit rotates the piston rotor in the compression chamber formed by a cylinder body sandwiched by a pair of bearings, thereby gradually reducing the volume of the compression chamber to compress the refrigerant. The compressed refrigerant is guided from the discharge hole to the space where the driving unit is arranged via the discharge valve.

[0093] According to the rotary compressor involved in the first aspect of the present invention, a discharge valve is accommodated in a recess formed in an opposing surface opposed to a driving portion, and compressed refrigerant is discharged from the discharge valve toward the recess. Since an inclined portion is formed in the recess, the flow direction of the refrigerant discharged from the discharge valve toward the recess is changed in a manner that approaches the opposing surface from the bottom in stages. Therefore, compared with the case where the flow direction of the refrigerant discharged from the discharge valve toward the recess is changed in only one stage, the pressure loss of the refrigerant can be suppressed.

[0094] The rotary compressor involved in the second aspect of the present invention is in the first aspect, wherein in the discharge valve, the base end is fixed to the bottom of the recess, and the front end is arranged at the discharge hole, and the inclined portion is formed along the extension direction from the base end of the discharge valve toward the front end.

[0095] According to the rotary compressor involved in the second embodiment of the present invention, since the inclined portion is formed along the extension direction from the base end portion toward the front end portion of the discharge valve, the flow direction of the refrigerant can be changed in a manner that gradually approaches the opposing surface from the bottom along the extension direction in which the discharge valve opens to guide the refrigerant.

[0096] In the rotary compressor involved in the third embodiment of the present invention, in the first embodiment or the second embodiment, when observing the opposing surface of the bearing along the axis, the inclined portion has: a first recess (4Ad21) formed in a circular shape with the discharge hole as the center; and a second recess (4Ad22) formed in a circular shape with a position separated from the discharge hole as the center and configured to overlap with the first recess, the height of the first recess from the bottom to the opposing surface is a first height, and the height of the second recess from the bottom to the opposing surface is a second height lower than the first height.

[0097] According to the rotary compressor involved in the third aspect of the present invention, the inclined portion has a first recess and a second recess, and the second height from the bottom of the second recess to the opposing surface is lower than the first height from the bottom of the first recess to the opposing surface. Therefore, the flow direction of the refrigerant discharged from the discharge valve toward the recess is changed in at least two stages, that is, the end of the first recess and the end of the second recess, in a manner that approaches the opposing surface from the bottom. Therefore, compared with the case where the flow direction of the refrigerant discharged from the discharge valve toward the recess is changed only in one stage, that is, at the end of the recess, the pressure loss of the refrigerant can be further suppressed.

[0098] In the rotary compressor according to a fourth aspect of the present invention, in the third aspect, a first diameter of the first recessed portion is at least twice the diameter of the discharge hole.

[0099] According to the rotary compressor involved in the fourth embodiment of the present invention, by setting the first diameter of the first recess to be more than twice the diameter of the discharge hole, it is possible to prevent excessive pressure loss caused by the refrigerant discharged from the discharge hole colliding with the recess at a position that does not meet twice the diameter of the discharge hole.

[0100] In the rotary compressor according to a fifth aspect of the present invention, in the third aspect, a second diameter of the second recessed portion is equal to a first diameter of the first recessed portion.

[0101] According to the rotary compressor involved in the fifth aspect of the present invention, since the second diameter of the second recess is the same as the first diameter of the first recess, the same cutting tool can be used to form the first recess and the second recess on the opposing surface of the bearing.

[0102] In the rotary compressor according to a sixth aspect of the present invention, in the third aspect, a second diameter of the second recessed portion is larger than a first diameter of the first recessed portion.

[0103] According to the rotary compressor involved in the sixth embodiment of the present invention, since the second diameter of the second recess is larger than the first diameter of the first recess, the pressure loss when the refrigerant collides with the end surface of the second recess can be reduced compared to the case where the second diameter is made the same as the first diameter.

[0104] In the manufacturing method of a rotary compressor involved in the seventh aspect of the present invention, the rotary compressor comprises: a shell having a cylindrical portion extending along the axis and in the vertical direction; a compression portion, which is accommodated in the shell and compresses the refrigerant; and a drive portion, which is accommodated in the shell and drives the compression portion by rotating a rotating shaft extending along the axis, the compression portion comprising: a piston rotor fixed to the rotating shaft and rotating eccentrically relative to the axis; a cylinder body that accommodates the piston rotor; a pair of bearings that support the rotating shaft so that it can rotate freely around the axis and are arranged to clamp the rotating shaft along the axis. The cylinder body is supported to form a compression chamber for accommodating the piston rotor; and a discharge valve is installed on one of the pair of bearings and opens and closes a discharge hole for discharging the refrigerant compressed in the compression chamber. The manufacturing method of the rotary compressor includes the following steps: forming a recess for accommodating the discharge valve by cutting an opposing surface of one of the pair of bearings that is opposite to the driving part; and forming the discharge hole passing through the axis line at the bottom of the recess, and in the step of forming the recess, a slope is formed in which the height from the bottom to the opposing surface becomes lower as the distance from the discharge hole becomes longer.

[0105] According to the manufacturing method of the rotary compressor involved in the seventh aspect of the present invention, in the process of forming the recess, the opposing surface of one of the pair of bearings that is opposed to the driving part is cut to form an inclined portion whose height from the bottom to the opposing surface decreases as the distance from the discharge hole increases. Since the recess having the inclined portion is formed by cutting, it is possible to easily manufacture a bearing having a smaller outer diameter (for example, less than Φ95 [mm]) than in the case of a bearing having the recess formed by casting.

[0106] According to the rotary compressor manufactured by the manufacturing method of the rotary compressor involved in the seventh embodiment of the present invention, a discharge valve is accommodated in a recess formed in the opposite surface opposite to the driving part, and the compressed refrigerant is discharged from the discharge valve toward the recess. Since an inclined portion is formed in the recess, the flow direction of the refrigerant discharged from the discharge valve toward the recess is changed in a manner that approaches the opposite surface from the bottom in stages. Therefore, compared with the case where the flow direction of the refrigerant discharged from the discharge valve toward the recess is changed by only one stage, the pressure loss of the refrigerant can be suppressed.

[0107] The manufacturing method of the rotary compressor involved in the 8th aspect of the present invention is as follows: in the 7th aspect, in the process of forming the recess, by cutting the opposing surface, when observing the opposing surface of the bearing along the axis, a first recessed portion in a circular shape centered on the discharge hole and a second recessed portion in a circular shape centered on a position separated from the discharge hole and arranged to overlap with the first recessed portion are formed as the inclined portion, the height of the first recessed portion from the bottom to the opposing surface is a first height, and the height of the second recessed portion from the bottom to the opposing surface is a second height lower than the first height.

[0108] According to the manufacturing method of the rotary compressor involved in the 8th embodiment of the present invention, the first recess and the second recess are formed as the inclined portion by cutting the opposing surface, and the rotary compressor is manufactured in which the second height from the bottom of the second recess to the opposing surface is lower than the first height from the bottom of the first recess to the opposing surface. Therefore, the flow direction of the refrigerant discharged from the discharge valve toward the recess is changed in at least two stages, that is, the end of the first recess and the end of the second recess, in a manner that approaches the opposing surface from the bottom. Therefore, compared with the case where the flow direction of the refrigerant discharged from the discharge valve toward the recess is changed only in one stage, that is, at the end of the recess, the pressure loss of the refrigerant can be further suppressed.

[0109] In the method for manufacturing a rotary compressor according to a ninth aspect of the present invention, in the eighth aspect, a first diameter of the first recessed portion is at least twice the diameter of the discharge hole.

[0110] According to the manufacturing method of the rotary compressor involved in the 9th aspect of the present invention, by setting the first diameter of the first recess to be more than twice the diameter of the discharge hole, it is possible to prevent excessive pressure loss caused by the refrigerant discharged from the discharge hole colliding with the recess at a position that does not meet twice the diameter of the discharge hole.

[0111] In the method for manufacturing a rotary compressor according to a tenth aspect of the present invention, in the eighth aspect, a second diameter of the second recessed portion is the same as a first diameter of the first recessed portion.

[0112] According to the manufacturing method of the rotary compressor involved in the 10th aspect of the present invention, since the second diameter of the second recess is the same as the first diameter of the first recess, the same cutting tool can be used for processing when cutting the opposing surface of the bearing to form the first recess and the second recess.

[0113] Explanation of symbols

[0114] 1-rotary compressor, 2-housing, 3-rotating shaft, 4A-upper bearing, 4Aa-discharge hole, 4Ab-opposing surface, 4Ac-fastening hole, 4Ad-recess, 4Ad1-bottom, 4Ad2-inclined portion, 4Ad21-first recess, 4Ad22-second recess, 4Ad23-third recess, 4B-lower bearing, 5-electric motor (drive unit), 6, 6A, 6B-rotary compression unit, 10-compressor body, 11-intake pipe, 12-liquid storage tank, 13-discharge pipe, 14-bracket, 15-inlet pipe, 21-body, 21a-inner surface, 22-upper cover, 23-lower cover, 24-opening, 25-intake port, 60-cylinder body, 60A-compression chamber, 60B-intake hole, 61-bolt, 62-eccentric shaft, 63-piston rotor, 64-discharge valve, 64a-valve core, 64a1-base end, 64a2-front end, 64b-retaining frame, 64c-fastening bolt, 65-discharge cover, CL-rotation axis, FL-setting surface, H, H1, H2, H3-height, HD-horizontal direction, VD-vertical direction, Z1, Z2-axis.

Claims

1. A rotary compressor comprising: The housing has a cylindrical portion extending along the axis and in a vertical direction; a compression unit, contained in the shell and configured to compress the refrigerant; and a driving unit, which is accommodated in the housing and drives the compression unit by rotating a rotating shaft extending along the axis, The compression part has: A piston rotor, fixed to the rotating shaft and rotating eccentrically relative to the axis; A cylinder body, accommodating the piston rotor; a pair of bearings that rotatably support the rotating shaft about the axis and are arranged to sandwich the cylinder along the axis to form a compression chamber for accommodating the piston rotor; and a discharge valve mounted on one of the pair of bearings and opening and closing a discharge hole for discharging the refrigerant compressed in the compression chamber; A recess for accommodating the discharge valve is formed on a surface of one of the pair of bearings that faces the drive unit. The discharge hole is formed at the bottom of the recess and penetrates along the axis. The recess has an inclined portion formed therein so that the height from the bottom to the facing surface decreases as the distance from the discharge hole increases.

2. The rotary compressor according to claim 1, wherein: In the discharge valve, the base end portion is fixed to the bottom portion of the recess, and the front end portion is arranged at the discharge hole. The inclined portion is formed along an extending direction from the base end portion toward the front end portion of the discharge valve.

3. The rotary compressor according to claim 1 or 2, wherein: When the facing surface of the bearing is observed along the axis, the inclined portion includes: a first recessed portion formed in a circular shape with the discharge hole as the center; and a second recessed portion formed in a circular shape with a position separated from the discharge hole as the center and arranged to overlap with the first recessed portion. A height of the first recessed portion from the bottom to the facing surface is a first height, and a height of the second recessed portion from the bottom to the facing surface is a second height that is lower than the first height.

4. The rotary compressor according to claim 3, wherein: A first diameter of the first recessed portion is at least twice the diameter of the discharge hole.

5. The rotary compressor according to claim 3, wherein: A second diameter of the second recess is the same as a first diameter of the first recess.

6. The rotary compressor according to claim 3, wherein: A second diameter of the second recessed portion is larger than a first diameter of the first recessed portion.

7. A method for manufacturing a rotary compressor, wherein: The rotary compressor comprises: The housing has a cylindrical portion extending along the axis and in a vertical direction; a compression unit, which is accommodated in the shell and compresses the refrigerant; and a driving unit, which is accommodated in the housing and drives the compression unit by rotating a rotating shaft extending along the axis, The compression part has: A piston rotor, fixed to the rotating shaft and rotating eccentrically relative to the axis; A cylinder body, accommodating the piston rotor; a pair of bearings that rotatably support the rotating shaft about the axis and are arranged to sandwich the cylinder along the axis to form a compression chamber for accommodating the piston rotor; and a discharge valve mounted on one of the pair of bearings and opening and closing a discharge hole for discharging the refrigerant compressed in the compression chamber; The manufacturing method of the rotary compressor comprises the following steps: A recess for accommodating the discharge valve is formed by cutting a surface of one of the pair of bearings that is opposed to the drive unit; and The discharge hole is formed at the bottom of the recess and penetrates along the axis. In the step of forming the recess, an inclined portion is formed in which the height from the bottom to the facing surface decreases as the distance from the discharge hole increases.

8. The method for manufacturing a rotary compressor according to claim 7, wherein: In the step of forming the recess, by cutting the opposing surface, when the opposing surface of the bearing is viewed along the axis, a first recessed portion having a circular shape centered on the discharge hole and a second recessed portion having a circular shape centered on a position separated from the discharge hole and arranged to overlap with the first recessed portion are formed as the inclined portion, A height of the first recessed portion from the bottom to the facing surface is a first height, and a height of the second recessed portion from the bottom to the facing surface is a second height that is lower than the first height.

9. The method for manufacturing a rotary compressor according to claim 8, wherein: A first diameter of the first recessed portion is at least twice the diameter of the discharge hole.

10. The method for manufacturing a rotary compressor according to claim 8, wherein: A second diameter of the second recess is the same as a first diameter of the first recess.

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