WO2023166628A1

WO2023166628A1 - Hermetic compressor

Info

Publication number: WO2023166628A1
Application number: PCT/JP2022/008938
Authority: WO
Inventors: 貴也木本
Original assignee: 三菱電機株式会社
Priority date: 2022-03-02
Filing date: 2022-03-02
Publication date: 2023-09-07

Abstract

This hermetic compressor comprises: a hermetic container in which an oil reservoir for storing refrigerating machine oil is formed; a compression mechanism unit that is arranged in the hermetic container and compresses a refrigerant; an electric motor unit that is arranged in the hermetic container above the compression mechanism unit and drives the compression mechanism unit; a main shaft that transmits the rotational force of the electric motor unit to the compression mechanism unit; and a bearing unit that rotatably supports the main shaft below the electric motor unit. In the hermetic compressor, oil in the oil reservoir is supplied to the bearing unit through an oil supply hole formed in the main shaft. The hermetic compressor includes a hollow cover that is fixed to the electric motor unit and arranged concentrically with respect to the main shaft between the electric motor unit and the compression mechanism unit, and into which the refrigerating machine oil that lubricated the bearing unit flows, the cover having a conical shape with a diameter increasing from top to bottom.

Description

hermetic compressor

The present disclosure relates to a hermetic compressor mounted on an air conditioner or the like.

A conventional hermetic compressor is connected to an electric motor section having a stator and a rotor in a closed container having an oil reservoir at the bottom, and a main shaft below the electric motor section. and a compression mechanism that compresses the Refrigerant compressed by the compression mechanism is discharged from the compression mechanism into the sealed container, and discharged from the discharge pipe to the outside of the sealed container. In this type of hermetic compressor, the refrigerating machine oil in the oil reservoir is supplied to the bearing that rotatably supports the main shaft to lubricate the bearing. Ejected. In a hermetic compressor, the refrigerating machine oil discharged from the end of the bearing is caught in the refrigerant gas flowing inside the closed container and flows out of the closed container together with the refrigerant gas. It is likely to run out.

On the other hand, there is a hermetic compressor in which a cylindrical cover is fixed to the lower end face of the rotor of the electric motor section (see Patent Document 1, for example). In the hermetic compressor of Patent Literature 1, the cover is concentric with the main shaft and arranged at a height position that includes the end portion of the bearing. In the hermetic compressor of Patent Document 1, the refrigerating machine oil discharged from the end of the bearing is received by the inner wall surface of the cover, and the refrigerating machine oil adhering to the inner wall surface is blown out of the cover from the lower end of the cover by centrifugal force, The blown refrigerating machine oil is returned to the oil reservoir.

JP-A-2002-327693

In the hermetic compressor of Patent Document 1, the cover is cylindrical, and the inner wall surface of the cover is a vertical surface extending in the axial direction. Therefore, the refrigerating machine oil adhering to the inner wall surface of the cover is mainly subjected to centrifugal force in the radial direction, and only its own weight acts in the direction of gravity. In other words, in the hermetic compressor of Patent Document 1, most of the force acting on the refrigerating machine oil adhering to the inner wall surface of the cover when it is blown out of the cover from the lower end of the cover is centrifugal force in the radial direction. Yes, the force in the direction of gravity is small. For this reason, the refrigerating machine oil blown outside the cover from the lower end of the cover tends to be swirled up by a slight swirling flow of the refrigerant gas flowing in the closed container, and is discharged out of the hermetic compressor together with the refrigerant gas flow.

The present disclosure has been made in view of these points, and aims to suppress the refrigerating machine oil blown out of the cover from the lower end of the cover from being blown up by the refrigerant gas flow and discharged outside the hermetic compressor. An object of the present invention is to provide a hermetic compressor capable of

A hermetic compressor according to the present disclosure includes a hermetic container in which an oil reservoir portion for storing refrigerator oil is formed, a compression mechanism portion disposed in the hermetic container for compressing a refrigerant, and an upper portion of the compression mechanism portion in the hermetic container. an electric motor portion disposed in the compression mechanism portion; a main shaft for transmitting rotational force of the electric motor portion to the compression mechanism portion; and a bearing portion for rotatably supporting the main shaft below the electric motor portion; A hermetic compressor in which oil is supplied to a bearing portion through an oil supply hole formed in a main shaft. and has a hollow cover into which refrigerating machine oil lubricating the bearings flows. The cover has a conical shape whose diameter increases from top to bottom.

According to the present disclosure, the hermetic compressor includes a hollow cover into which refrigerating machine oil lubricating the bearings flows, and the cover has a conical shape whose diameter increases from top to bottom. Due to the conical shape of the cover, the centrifugal force acting on the refrigerating machine oil adhering to the inner wall surface of the cover includes an obliquely downward force component along the inner wall surface of the cover. That is, a force in the direction of gravity acts on the refrigerating machine oil adhering to the inner wall surface of the cover, and this force in the direction of gravity acts on the refrigerating machine oil when it is blown out from the lower end of the cover to the outside of the cover. Therefore, the hermetic compressor can prevent the refrigerating machine oil from being drawn up by the refrigerant gas flow and discharged to the outside of the hermetic compressor.

1 is a schematic longitudinal sectional view of a hermetic compressor according to Embodiment 1; FIG. 2 is a schematic enlarged view of the vicinity of an upper bearing of the hermetic compressor according to Embodiment 1. FIG. 2 is a plan view of a discharge muffler of the hermetic compressor according to Embodiment 1. FIG. FIG. 10 is an explanatory view of the action of the cover of the hermetic compressor according to the comparative example; FIG. 4 is an explanatory view of the action of the cover of the hermetic compressor according to Embodiment 1; FIG. 8 is a schematic enlarged view of the vicinity of an upper bearing of a hermetic compressor according to Embodiment 2; FIG. 8 is a plan view of a discharge muffler of a hermetic compressor according to Embodiment 2; FIG. 11 is a schematic enlarged view of the vicinity of an upper bearing of a hermetic compressor according to Embodiment 3; FIG. 11 is a plan view of a discharge muffler of a hermetic compressor according to Embodiment 4; FIG. 11 is a schematic enlarged view of the vicinity of an upper bearing of a hermetic compressor according to Embodiment 4; FIG. 5 is a plan view of a discharge muffler of a hermetic compressor according to a comparative example; It is a schematic enlarged view of the upper bearing vicinity in the hermetic compressor which concerns on a comparative example.

Embodiments will be described below based on the drawings. It should be noted that the present disclosure is not limited by the embodiments described below. In addition, in the following drawings including FIG. 1, the relative dimensional relationship and shape of each component may differ from the actual ones. Also, in the following drawings, the same reference numerals denote the same or equivalent parts, and this applies throughout the specification.

Embodiment 1.
FIG. 1 is a schematic longitudinal sectional view of a hermetic compressor 100 according to Embodiment 1. FIG. FIG. 2 is a schematic enlarged view of the vicinity of the upper bearing 14 of the hermetic compressor 100 according to the first embodiment. FIG. 3 is a plan view of discharge muffler 17 of hermetic compressor 100 according to the first embodiment. In FIG. 3 , the cover 60 and the coolant channel holes 23 are indicated by dotted lines in order to clarify the positional relationship between the discharge muffler 17 and the cover 60 and the coolant channel holes 23 .

In the following, an example in which the hermetic compressor 100 is a rotary compressor will be described. It is sufficient if the compressor is provided with a bearing end of . In the first embodiment, the hermetic compressor 100 is described as a rotary compressor with one cylinder, but may be a rotary compressor with a plurality of cylinders.

The hermetic compressor 100 includes a compression mechanism section 10 that compresses the refrigerant and an electric motor section 20 that drives the compression mechanism section 10 inside the hermetic container 1 . The compression mechanism section 10 and the electric motor section 20 are connected by the main shaft 11 , and the compression mechanism section 10 is housed in the lower portion of the sealed container 1 and the electric motor section 20 is housed in the upper portion of the sealed container 1 . In the following description, the longitudinal direction of the sealed container 1 is called the axial direction, and the direction perpendicular to the axial direction is called the radial direction. The inner wall surface side of the sealed container 1 is defined as the outer side. The hermetic compressor 100 is a so-called vertical compressor that is used with the main shaft 11 in the direction of gravity.

A suction muffler 41 is provided adjacent to the closed container 1 outside the closed container 1 . The suction muffler 41 has a role of storing the liquid refrigerant and silencing the refrigerant noise. The suction muffler 41 is connected to a later-described cylinder 13 of the compression mechanism 10 by a suction connecting pipe 42 . A discharge pipe 43 for discharging the refrigerant compressed by the compression mechanism section 10 is connected to the upper portion of the sealed container 1 . At the bottom of the closed container 1, an oil reservoir 50 is formed to hold refrigerator oil. A portion of the compression mechanism 10 is immersed in the oil reservoir 50 . Refrigerating machine oil stored in oil reservoir 50 is supplied to main shaft 11, compression mechanism 10, upper bearing 14, lower bearing 15, etc. through oil supply hole 11a formed in main shaft 11. As shown in FIG. The oil supply hole 11a has a vertical hole 11a1 extending in the axial direction and a plurality of horizontal holes 11a2 extending radially from the vertical hole 11a1.

The main shaft 11 transmits the rotational force of the electric motor section 20 to the compression mechanism section 10 and is rotatably supported by the upper bearing 14 and the lower bearing 15 . The upper bearing 14 has a bearing portion 14a and a flange portion 14b. The bearing portion 14a is a cylindrical portion that rotatably supports the main shaft 11. As shown in FIG. The flange portion 14b is located at one end in the axial direction of the bearing portion 14a and is a portion that expands in a disc shape from the hole through which the main shaft 11 passes. Similarly, the lower bearing 15 has a bearing portion 15a and a disk-shaped flange portion 15b extending on one side of the bearing portion 15a. The bearing portion 14a and the bearing portion 15a are composed of slide bearings.

The compression mechanism section 10 includes an annular cylinder 13, a piston 16 housed in the cylinder 13 and slidably fitted to the eccentric shaft section 12 of the main shaft 11, and vanes (not shown). The vanes are slidably arranged in vane grooves (not shown) provided in the cylinder 13 . The radially outer side of the vane is open to the space of the airtight atmosphere of the airtight container 1 . Openings at both axial ends of the cylinder 13 are closed by the flange portion 14 b of the upper bearing 14 and the flange portion 15 b of the lower bearing 15 to form a cylinder chamber 30 inside the cylinder 13 .

A suction port 40 extending radially is formed in the cylinder 13 , and a suction coupling pipe 42 extending from a suction muffler 41 is connected to the suction port 40 . As a result, the refrigerant sucked into the sealed container 1 from the intake muffler 41 is guided to the cylinder chamber 30 . Further, the cylinder 13 is formed with a discharge port (not shown) through which the refrigerant compressed in the cylinder chamber 30 is discharged from the cylinder chamber 30 . The discharge port (not shown) communicates with a through hole (not shown) of a discharge mechanism (not shown) provided in the flange portion 14b of the upper bearing 14, and a discharge muffler 17 covers the discharge mechanism. is attached to the upper bearing 14 .

The discharge muffler 17 has a plate-shaped upper wall portion 17a, a side wall portion 17b extending downward from the outer peripheral edge of the upper wall portion 17a, and a flange portion 17c protruding radially outward from the lower end portion of the side wall portion 17b. and covers the space into which the refrigerant compressed by the compression mechanism 10 is discharged. In FIG. 3, illustration of the flange portion 17c is omitted. A through hole 17a1 is formed in the central portion of the upper wall portion 17a, and the bearing portion 14a of the upper bearing 14 is passed through the through hole 17a1. A discharge portion 171 for discharging the refrigerant in the discharge muffler 17 into the sealed container is formed in the upper wall portion 17a.

The discharge part 171 is a part that discharges the refrigerant in the cover 60 from a position higher in the axial direction than the lower end surface 60b of the cover 60, as shown in FIG. The discharge portion 171 has a discharge hole 171a passing through the upper wall portion 17a and a cylindrical discharge wall 171b projecting upward from the peripheral wall of the discharge hole 171a. 1 and 2, the discharge wall 171b has a burring shape formed by burring the upper wall portion 17a of the discharge muffler 17. The processing method is not limited.

The discharge part 171 is located outside the outer peripheral edge 60c of the lower end surface 60b of the cover 60. That is, the discharge portion 171 is located outside the cover 60 when viewed in the axial direction as shown in FIG. Moreover, as shown in FIG. 3, a plurality of ejection portions 171 are formed at intervals in the circumferential direction.

The electric motor section 20 is arranged above the upper bearing 14 . The electric motor section 20 includes a stator 22 formed in an annular shape and a rotor 21 rotatably supported inside the stator 22 . A coolant passage hole 23 is formed through the rotor 21 in the axial direction. As shown in FIG. 3, a plurality of coolant passage holes 23 are formed at intervals in the circumferential direction. The refrigerant passage hole 23 guides the refrigerant gas discharged from the compression mechanism portion 10 to the upper portion of the closed container 1, and allows the refrigerating machine oil guided to the upper portion of the closed container 1 together with the refrigerant gas to fall to the lower portion of the closed container 1. have the role of Also, between the stator 22 and the closed container 1 , there is a space that has the same function as the coolant passage hole 23 and that communicates the upper portion and the lower portion of the closed container 1 .

A cover 60 is arranged between the electric motor section 20 and the discharge muffler 17 to prevent the refrigerating machine oil from being lifted up and discharged from the hermetic compressor 100 . The cover 60 is hollow and penetrates in the axial direction, and has a conical shape whose diameter increases from the top to the bottom. In this specification, the expression “conical” refers to a general shape in which the diameter increases from the top to the bottom, and does not strictly refer to a cone with a sharp tip. The cover 60 is arranged concentrically with the main shaft 11 so that the refrigerating machine oil flows into the cover 60 after lubricating the bearing portion 14a. Specifically, the opening diameter of the upper end portion of the cover 60 is larger than the outer diameter of the bearing portion 14a, and a gap is formed between the cover 60 and the bearing portion 14a. After lubricating the bearing portion 14a, the refrigerating machine oil flows out from the upper end 141 of the bearing portion 14a and flows into the cover 60 through the gap. The cover 60 is fixed to the lower end surface of the rotor 21 and rotates together with the rotor 21 .

1 and 2, the upper end of the cover 60 is positioned lower than the upper end 141 of the bearing portion 14a. Alternatively, the cover 60 may be configured to cover the upper end 141 of the bearing portion 14a. That is, the positional relationship in the axial direction between the upper end of the cover 60 and the upper end 141 of the bearing portion 14a may be reversed from that shown in the drawing. In short, the hermetic compressor 100 only needs to be configured such that the refrigerating machine oil after lubricating the bearing portion 14 a flows into the cover 60 .

An oil separation plate 18 is fixed to the upper portion of the main shaft 11 to separate the refrigerant oil containing the refrigerant oil. The oil separator plate 18 may be fixed to the rotor 21 . The oil separation plate 18 rotates with the rotation of the main shaft 11, and can separate the refrigerating machine oil from the refrigerant by flying it in the outer peripheral direction by centrifugal force. The refrigerating machine oil separated by the oil separation plate 18 falls into the oil reservoir 50 through a gap or the like in the electric motor section 20 .

Next, the operation of the hermetic compressor 100 configured as described above will be described. The rotational force of the electric motor portion 20 is transmitted to the main shaft 11 by driving the electric motor portion 20 . The rotational force transmitted to the main shaft 11 is transmitted to the eccentric shaft portion 12 attached to the main shaft 11 , and the piston 16 rotates eccentrically within the cylinder chamber 30 together with the eccentric shaft portion 12 .

When the piston 16 rotates within the cylinder chamber 30 , low-pressure refrigerant is supplied into the cylinder chamber 30 from the intake muffler 41 via the intake connecting pipe 42 and the intake port 40 . The rotation of the piston 16 reduces the volume of the cylinder chamber 30 and compresses the refrigerant. A vane (not shown) is pressed against the piston 16 by the high pressure refrigerant in the closed container 1 . The vane slides radially in the vane groove in conjunction with the movement of the piston 16 and serves to divide the cylinder chamber 30 into a low-pressure space and a high-pressure space. Refrigerant sucked into the low-pressure space in the cylinder chamber 30 from the suction port 40 is compressed in the high-pressure space. The compressed refrigerant is once discharged into the discharge muffler 17 from a discharge mechanism (not shown) formed in the upper bearing 14 .

The refrigerant discharged into the discharge muffler 17 is discharged from the discharge portion 171 of the discharge muffler 17 into the internal space of the sealed container 1 . The refrigerant gas discharged into the internal space of the sealed container 1 flows into the space above the electric motor section 20 through the refrigerant passage holes 23 formed in the electric motor section 20 and the like. At this time, the refrigerating machine oil is centrifugally separated from the refrigerant gas by the oil separation plate 18 fixed to the upper part of the main shaft 11, and the refrigerant gas is discharged from the discharge pipe 43 to the outside of the sealed container 1 and flows through the refrigerant circuit, whereupon the refrigerating machine oil is discharged. is returned to the oil reservoir 50 along the inner wall surface of the sealed container 1.

The main shaft 11 of the hermetic compressor 100 functions as a centrifugal pump. In the hermetic compressor 100, as the main shaft 11 rotates, the vertical hole 11a1 of the oil supply hole 11a in the main shaft 11 functions as a centrifugal pump to suck up the refrigerating machine oil from the oil reservoir 50. FIG. The sucked refrigerating machine oil passes through the vertical hole 11a1 and the horizontal hole 11a2, and is supplied to the lower bearing 15, the cylinder chamber 30, and the bearing portion 14a of the upper bearing . The refrigerator oil supplied to the bearing portion 14 a flows out from the upper end 141 of the upper bearing 14 . Refrigerating machine oil flowing out from the upper end 141 of the upper bearing 14 flows into the cover 60 that rotates together with the rotor 21, collides with the inner wall surface 60a, and adheres thereto. Refrigerating machine oil adhering to the inner wall surface 60a of the cover 60 reaches the lower end of the cover 60 along the inner wall surface 60a and is blown out of the cover 60 by centrifugal force. The refrigerating machine oil blown out of the cover 60 is sprayed against the upper wall portion 17a of the discharge muffler 17, flows outward in the radial direction through the upper wall portion 17a, and then flows downward along the side wall portion 17b to form an oil pool. Returned to section 50 .

Here, more detailed actions of the cover 60 will be described.

FIG. 4 is an explanatory view of the action of the cover 600 of the hermetic compressor according to the comparative example. 5A and 5B are explanatory views of the action of the cover 60 of the hermetic compressor according to the first embodiment.

The cover 600 of the comparative example has a cylindrical shape extending in the axial direction as shown in FIG. 4, and the inner diameter is the same throughout the axial direction. Therefore, since the inner wall surface 600a is a vertical surface extending in the vertical direction, the centrifugal force F1 acting on the refrigerating machine oil 700 inside the cover 600 rotating in the direction of the arrow R is only a radial component. Therefore, when the refrigerator oil 700 flows out from the lower end portion of the cover 600, it is thrown in the radial direction, in other words, in the lateral direction.

On the other hand, the cover 60 of Embodiment 1 has a conical shape whose diameter increases from the top to the bottom as shown in FIG. Therefore, the inner wall surface 60a is a sloped surface that slopes radially outward toward the bottom. Therefore, the centrifugal force F1 acting on the refrigerating machine oil 70 adhering to the inner wall surface 60a of the cover 60 is divided into a force component Fa along the inner wall surface 60a and a force component Fb perpendicular to the inner wall surface 60a. decomposed. In this manner, the refrigerating machine oil 70 is subjected to the obliquely downward force component Fa along the inner wall surface 60a, so that the refrigerating machine oil 70 is flung obliquely downward from the lower end of the cover 60 radially outward. Here, the force component Fa includes a force component in the direction of gravity. Therefore, the refrigerating machine oil 70 blown from the lower end portion of the cover 60 is less likely to be swept up by the refrigerant gas.

Therefore, in the hermetic compressor 100 of Embodiment 1, the refrigerating machine oil is drawn up by the refrigerant gas flowing in the hermetic container 1, specifically, by the refrigerant gas discharged from the discharge muffler 17, and flows out of the hermetic compressor. It can be suppressed that it is discharged to. The refrigerating machine oil blown obliquely downward from the lower end of the cover 60 is sprayed onto the upper wall portion 17a of the discharge muffler 17, and then downward along the upper wall portion 17a and the side wall portion 17b of the discharge muffler 17. It flows back to the oil reservoir 50 .

Also, the discharge part 171 discharges the refrigerant from a position higher than the lower end surface 60 b of the cover 60 . For this reason, the hermetic compressor 100 has a path for refrigerating machine oil that flows out from the lower end of the cover 60 and returns to the oil reservoir 50, and a flow of refrigerant gas that is discharged from the discharge part 171 and directed to the refrigerant flow path holes 23 and the like. can be separated from the road. As a result, the hermetic compressor 100 can prevent the refrigerating machine oil that has flowed out from the lower end portion of the cover 60 from being involved in the refrigerant gas that flows out from the discharge portion 171 and heads toward the refrigerant flow path holes 23 and the like. The amount discharged to the outside of the hermetic compressor can be reduced.

Further, the axial distance G between the lower end surface 60b of the cover 60 and the upper wall portion 17a of the discharge muffler 17 is significantly smaller than the radial distance L between the lower end surface 60b of the cover 60 and the upper bearing 14. (G<L). With this configuration, most of the refrigerating machine oil discharged from the lower end of the cover 60 is not swirled up and immediately adheres to the upper wall portion 17a of the discharge muffler 17 and is captured. Furthermore, if the axial distance H between the lower end surface 60b of the cover 60 and the upper end surface 171a1 of the discharge portion 171 is set to be greater than the axial distance G between the lower end surface 60b and the upper wall portion 17a of the discharge muffler 17, Good (H>G). By doing so, the effect of preventing the refrigerating machine oil discharged from the lower end portion of the cover 60 from being stirred up by the gas discharged from the discharge portion 171 is enhanced.

The hermetic compressor 100 of Embodiment 1 is a compressor in which the oil in the oil reservoir 50 formed in the hermetic container 1 is supplied to the bearing 15a through the oil supply hole 11a formed in the main shaft 11. The hermetic compressor 100 is fixed to the electric motor portion 20 and arranged concentrically with the main shaft 11 between the electric motor portion 20 and the compression mechanism portion 10. A hollow cover 60 into which refrigerating machine oil lubricating the bearing portion 15a flows. Prepare. The cover 60 has a conical shape whose diameter increases from the top to the bottom.

With the above configuration, the inner wall surface 60a of the cover 60 of the hermetic compressor 100 forms an inclined surface that inclines radially outward as it goes downward. Therefore, the centrifugal force F1 acting on the refrigerating machine oil 70 adhering to the inner wall surface 60a has an obliquely downward force component Fa along the inner wall surface 60a. That is, a force in the direction of gravity acts on the refrigerating machine oil adhering to the inner wall surface 60a of the cover 60, and this force in the direction of gravity acts on the refrigerating machine oil when it is blown out from the lower end of the cover 60 to the outside of the cover. . Therefore, the hermetic compressor 100 can prevent the refrigerating machine oil that has flowed out from the lower end of the cover 60 from being drawn up by the refrigerant gas flowing in the hermetic container 1 and discharged to the outside of the hermetic compressor.

The hermetic compressor 100 of Embodiment 1 also includes a discharge muffler 17 that covers the space into which the refrigerant compressed by the compression mechanism 10 is discharged. The discharge muffler 17 is disposed between the compression mechanism portion 10 and the electric motor portion 20, and includes a plate-like upper wall portion 17a having a through hole 17a1 through which the bearing portion 15a is passed, and a lower portion from the outer peripheral edge of the upper wall portion 17a. and a side wall portion 17b extending to the The upper wall portion 17a of the discharge muffler 17 is formed with a discharge portion 171 having a discharge hole 171a for discharging the refrigerant in the discharge muffler 17 from a position higher than the lower end surface 60b of the cover 60 .

With the above configuration, the hermetic compressor 100 has a path for the refrigerating machine oil that flows out from the lower end of the cover 60 and returns to the oil reservoir 50, and a path for the refrigerant gas that is discharged from the discharge portion 171 and directed to the refrigerant passage holes 23 and the like. can be separated from the flow path. As a result, the hermetic compressor 100 can prevent the refrigerating machine oil that has flowed out from the lower end of the cover 60 from being caught in the refrigerant gas flowing in the hermetic container 1, and as a result, is discharged to the outside of the hermetic compressor. can be reduced.

Embodiment 2.
FIG. 6 is a schematic enlarged view of the vicinity of upper bearing 14 of hermetic compressor 100 according to the second embodiment. The configuration of the second embodiment is the same as that of the first embodiment except for the discharge muffler 17 . FIG. 7 is a plan view of discharge muffler 17 of hermetic compressor 100 according to the second embodiment. In FIG. 7 , the cover 60 and the coolant channel holes 23 are indicated by dotted lines in order to clarify the positional relationship between the discharge muffler 17 and the cover 60 and the coolant channel holes 23 . Further, illustration of the flange portion 17c is omitted in FIG. Hereinafter, the second embodiment will be described with a focus on the configuration different from the first embodiment, and the configurations not described in the second embodiment are the same as those in the first embodiment.

The discharge muffler 17 according to the second embodiment has a recess 172 recessed downward in the upper wall portion 17a of the discharge muffler 17 according to the first embodiment. A plurality of recesses 172 are formed at intervals in the circumferential direction as shown in FIG. Although FIG. 7 shows an example in which there are three depressions 172, the number of depressions 172 is not limited. When viewed in the axial direction, the recess 172 extends radially outward from a position radially inward of the inner peripheral edge 60d of the lower end surface 60b of the cover 60 to the side wall portion 17b, and is open radially outward. ing. Due to this depression 172, a part of the cover 60 does not face the upper wall portion 17a of the discharge muffler 17 and is open downward. Specifically, as shown in FIG. 7, the opening portion 62, which is a portion opened downward, is formed between the inner peripheral edge 60d of the lower end surface 60b of the cover 60 and the upper wall portion 17a of the discharge muffler 17 when viewed in the axial direction. It is a portion surrounded by the outer edge 17aa and indicated by dots.

Due to the above configuration, the refrigerating machine oil that has flowed out from the lower end of the cover 60 easily flows into the depression 172 through the open portion 62 which is wider than the gap between the lower end surface 60b of the cover 60 and the upper wall portion 17a of the discharge muffler 17. Arrows in FIG. 6 indicate the flow of the refrigerating machine oil in the cover 60 from the opening 62 into the depression 172 . In this way, the refrigerating machine oil that has flowed out from the lower end of the cover 60 can easily flow from the open portion 62 to the depression 172 , so to speak, to concentrate in the depression 172 . Thereby, in the hermetic compressor 100 , the discharge passage for the refrigerating machine oil can be separated from the discharge portion 171 . Therefore, the hermetic compressor 100 can suppress the refrigerating machine oil from being swirled up by the refrigerant gas flow discharged from the discharge portion 171 , as compared with the case where the discharge muffler 17 is not provided with the recess 172 .

The hermetic compressor 100 of the second embodiment can obtain the same effects as those of the first embodiment, and the following effects can be obtained by providing the recess 172 in the discharge muffler 17 . In the hermetic compressor 100 of the second embodiment, the discharge passage of the refrigerating machine oil and the refrigerant gas passage from the discharge portion 171 can be separated. can be suppressed.

Embodiment 3.
FIG. 8 is a schematic enlarged view of the vicinity of upper bearing 14 of hermetic compressor 100 according to the third embodiment. The configuration of the third embodiment is the same as that of the second embodiment except for the discharge muffler 17 . The following description focuses on the configuration of the third embodiment that differs from the second embodiment, and the configurations not described in the third embodiment are the same as those of the second embodiment.

A discharge muffler 17 according to Embodiment 3 differs from Embodiments 1 and 2 in the configuration of a discharge portion 171 . In the discharge muffler 17 of the third embodiment, the upper wall portion 17a is formed in a stepped shape to form a discharge portion 171. As shown in FIG. Specifically, the discharge portion 171 of Embodiment 3 has a convex portion 171c that protrudes upward from the upper wall portion 17a to a position higher than the height of the lower end surface 60b of the cover 60. The convex portion 171c has an axis It has a configuration in which a discharge hole 171a penetrating in the direction is formed.

With the above configuration, the discharge portion 171 discharges the refrigerant gas inside the cover 60 from a position higher in the axial direction than the lower end surface 60 b of the cover 60 . Therefore, the hermetic compressor 100 of the third embodiment can obtain the same effects as those of the first embodiment. Although FIG. 8 illustrates a configuration in which the discharge muffler 17 has the recess 172 of the second embodiment, the discharge muffler 17 of the third embodiment may be configured without the recess 172 . The discharge muffler 17 of the third embodiment can obtain the same effect as the first embodiment when it does not have the recess 172, and can obtain the same effect as the second embodiment when it has the recess 172. FIG.

Further, when the discharge portion 171 of Embodiment 1 is formed by burring a sheet metal, the height of the discharge wall 171b is limited by the diameter of the discharge hole 171a. On the other hand, since the discharge portion 171 of Embodiment 3 has a stepped shape, the convex portion 171c can be formed by press working or the like, and the height of the discharge portion 171 can be easily adjusted regardless of the diameter of the discharge hole 171a. The structure can make it taller. Since the height of the discharge portion 171 can be increased in the hermetic compressor 100 of Embodiment 3, the separation effect between the oil discharge channel and the refrigerant gas channel can be increased.

Embodiment 4.
Embodiment 4 specifies the radial positional relationship between the discharge hole 171a of the discharge muffler 17 and the refrigerant passage hole 23 in the above-described Embodiments 1 to 3. FIG.

9 is a plan view of the discharge muffler 17 of the hermetic compressor 100 according to Embodiment 4. FIG. In order to clarify the positional relationship between the discharge muffler 17, the cover 60, and the refrigerant passage holes 23, FIG. In FIG. 9 , C is an imaginary circle connecting the innermost ends, which are the radially inner ends of the coolant passage holes 23 . FIG. 10 is a schematic enlarged view of the vicinity of upper bearing 14 of hermetic compressor 100 according to the fourth embodiment. Hermetic compressor 100 according to Embodiment 4 is arranged such that at least part of discharge hole 171a is located inside imaginary circle C. As shown in FIG.

The effect of the above configuration will be explained in comparison with a comparative example.

FIG. 11 is a plan view of a discharge muffler of a hermetic compressor according to a comparative example. FIG. 12 is a schematic enlarged view of the vicinity of an upper bearing in a hermetic compressor according to a comparative example.

In both the fourth embodiment and the comparative example, the refrigerating machine oil flowing out from the lower end portion of the cover 60 is sprayed onto the upper wall portion 17a of the discharge muffler 17. Some of the refrigerating machine oil sprayed onto the upper wall portion 17a of the discharge muffler 17 may collide with the discharge wall 171b of the discharge portion 171 and be rolled up, or may be rolled up by the refrigerant gas flow or the like. 10 and 12, the white arrows indicate the swirl flow of the refrigerant gas, and the solid arrows indicate the flow of the refrigerating machine oil.

Here, in the comparative example shown in FIGS. 11 and 12, the discharge hole 1710 is positioned outside the virtual circle C when viewed in the axial direction. In this case, since there is no element that obstructs the flow of the refrigerating machine oil that is wound up in the path from the lower end of the cover 60 to the refrigerant flow path hole 23, the refrigerating machine oil that is stirred up as described above directly flows into the refrigerant flow path hole 23. easy to invade.

On the other hand, in the hermetic compressor 100 of Embodiment 4, at least part of the discharge hole 171a is located inside the virtual circle C as shown in FIGS. In this case, the refrigerating machine oil that has been lifted up as described above is spun in the centrifugal direction by the refrigerant gas flow discharged from the discharge hole 171 a and the swirl flow generated by the rotation of the rotor 21 , and directly into the refrigerant passage hole 23 . don't go

I will explain more specifically. It is assumed that the swirling flow generated near the discharge portion 171 by the refrigerant flow discharged from the discharge hole 171a acts from the upper portion to the outer peripheral portion of the discharge wall 171b and does not act on the inside of the discharge wall 171b. 10 and 12, in the comparative example shown in FIG. 12, the swirling flow indicated by the white arrow is located radially outward compared to FIG. ing. Therefore, in the configuration of the comparative example, the refrigerating machine oil that flows out from the lower end portion of the cover 60 and is swirled up is likely to go directly to the refrigerant passage hole 23 without being disturbed by the swirling flow.

On the other hand, in the hermetic compressor 100 of the fourth embodiment, the swirling flow moves radially inward and approaches the lower end of the cover 60 as compared with the comparative example, as shown in FIG. Therefore, the refrigerating machine oil that has flowed out from the lower end portion of the cover 60 and has been swirled up is caught in the swirling flow from the discharge hole 171 a and receives centrifugal force, and does not go directly to the refrigerant flow path hole 23 .

As described above, the hermetic compressor 100 of the fourth embodiment can further suppress the refrigerating machine oil that has flowed out from the lower end portion of the cover 60 from being swirled up and entering the refrigerant passage holes 23 . As a result, hermetic compressor 100 of Embodiment 4 can further suppress discharge of refrigerating machine oil to the outside of the hermetic compressor.

The hermetic compressor 100 of Embodiment 4 can obtain the same effects as those of Embodiments 1 to 3, and at least part of the discharge hole 171a is positioned inside the virtual circle C, It is possible to further suppress the refrigerating machine oil from being discharged to the outside of the hermetic compressor.

1 closed container, 10 compression mechanism, 11 main shaft, 11a oil supply hole, 11a1 vertical hole, 11a2 horizontal hole, 12 eccentric shaft, 13 cylinder, 14 upper bearing, 14a bearing, 14b flange, 15 lower bearing, 15a bearing, 15b flange portion 16 piston 17 discharge muffler 17a upper wall portion 17a1 through hole 17aa outer edge 17b side wall portion 17c flange portion 18 oil separation plate 20 electric motor portion 21 rotor 22 stator 23 Refrigerant passage hole 30 Cylinder chamber 40 Suction port 41 Suction muffler 42 Suction connecting pipe 43 Discharge pipe 50 Oil reservoir 60 Cover 60a Inner wall surface 60b Lower end surface 60c Outer peripheral edge 60d Inner peripheral edge 62 open part, 70 refrigerator oil, 100 hermetic compressor, 141 upper end, 171 discharge part, 171a discharge hole, 171a1 upper end surface, 171b discharge wall, 171c convex part, 172 recess.

Claims

A closed container in which an oil reservoir for storing refrigerating machine oil is formed; a compression mechanism arranged in the closed container for compressing a refrigerant; and a compression mechanism arranged above the compression mechanism in the closed container. a main shaft for transmitting the rotational force of the electric motor to the compression mechanism; and a bearing for rotatably supporting the main shaft below the electric motor. oil is supplied to the bearing portion through an oil supply hole formed in the main shaft,
a hollow cover that is fixed to the electric motor unit and arranged concentrically with respect to the main shaft between the electric motor unit and the compression mechanism unit and into which refrigerating machine oil lubricating the bearing unit flows;
The cover is a conical hermetic compressor whose diameter increases from the top to the bottom.
a plate-shaped upper wall portion disposed between the compression mechanism portion and the electric motor portion and having a through hole through which the bearing portion passes; and a side wall portion extending downward from an outer peripheral edge of the upper wall portion, A discharge muffler covering a space into which the refrigerant compressed by the compression mechanism is discharged,
2. The hermetic compressor according to claim 1, wherein the upper wall portion of the discharge muffler is formed with a discharge portion having a discharge hole for discharging the refrigerant in the discharge muffler from a position higher than the lower end surface of the cover. .
The discharge muffler has a recess recessed downward in the upper wall,
The recess extends radially outward from a position radially inward of the main shaft from the inner peripheral edge of the lower end surface of the cover to the side wall portion when viewed in the axial direction of the main shaft. A hermetic compressor according to claim 2.
The electric motor unit has a plurality of coolant passage holes penetrating in the axial direction of the main shaft at intervals in the circumferential direction,
The discharge hole of the discharge portion is arranged outside the cover, and at least a part of the discharge hole corresponds to the diameter of the main shaft of each of the plurality of refrigerant passage holes when viewed in the axial direction. 4. The hermetic compressor according to claim 2 or 3, wherein the compressor is arranged inside a virtual circle connecting the innermost ends of the directions.
The discharge portion has a projection projecting upward from the upper wall portion to a position higher than the lower end surface of the cover, and the discharge hole is formed through the projection in the axial direction of the main shaft. The hermetic compressor according to any one of claims 2 to 4, wherein the hermetic compressor is formed.