CN109804164B - Hermetic compressor - Google Patents

Abstract

A hermetic compressor (100) is provided with a drive shaft (4), a cylinder block (31), an upper bearing (33), a lower bearing (34), and muffling chambers (39a, 40a) in a compression mechanism (3). At least one of the upper bearing (33) and the lower bearing (34) is provided with flexible structure grooves (61, 64), the flexible structure grooves (61, 64) are open on the cylinder (31) side, a thin portion is formed between the flexible structure grooves (61, 64) and bearing holes (33c, 34c) of the upper bearing (33) or the lower bearing (34) through which the drive shaft (4) is inserted, and communication holes (63, 66) for communicating the flexible structure grooves (61, 64) and the sound-deadening chambers (39a, 40a) are provided in the flexible structure grooves (61, 64).

Description

Hermetic compressor

Technical Field

The present invention relates to a hermetic compressor used in a refrigerating and air-conditioning apparatus.

Background

The hermetic compressor includes a compression mechanism for compressing a refrigerant gas, an electric mechanism for driving the compression mechanism, and a hermetic container for housing the compression mechanism and the electric mechanism. The compression mechanism portion is constituted by a cylinder having a cylindrical inner space opened vertically, a cylindrical rotary plunger disposed in the cylinder, and a drive shaft for eccentrically rotating the rotary plunger. The compression mechanism unit sucks, compresses, and discharges refrigerant gas in the internal space of the cylinder by rotating the drive shaft. An opening portion of the inner space of the cylinder block is closed by an upper bearing and a lower bearing, and the upper bearing and the lower bearing support the drive shaft.

In the hermetic compressor having such a structure, when the compression mechanism compresses the refrigerant gas, a compression load acts on the drive shaft, and a deflection (a deviation in a direction perpendicular to the axial direction) occurs. There is a possibility that the upper bearing and the lower bearing are locally worn due to the deflection of the drive shaft.

Therefore, a hermetic compressor in which a flexible structure for absorbing the deflection of the drive shaft is formed in at least one of the upper bearing and the lower bearing is disclosed (for example, see patent document 1).

Patent document 1: japanese patent laid-open No. 2004-124834 (pages 4-5, FIG. 4)

The upper and lower bearings of the hermetic compressor are composed of a flange portion for closing the opening of the cylinder block and a cylindrical bearing portion having a bearing hole into which the drive shaft is inserted for shaft support. The flexible structure disclosed in patent document 1 facilitates minute deformation of the inner diameters of the bearing portions of the upper bearing and the lower bearing when the drive shaft is subjected to flexural deformation. Specifically, a flexible structural groove, which is an annular groove that opens at an end surface that is in contact with the cylinder and annularly surrounds an opening of the bearing hole, is provided at a position slightly spaced outward from an inner peripheral surface of the bearing hole of the bearing portion of the upper bearing and the lower bearing. The flexible structure groove has a circular cross section perpendicular to the axial direction, and a thin-walled cylindrical portion, i.e., a flexible structure, is formed between the inner circumferential surfaces of the bearing holes of the upper and lower bearings and the flexible structure groove.

With such a structure, the flexible structure, which is a thin cylindrical portion, is elastically deformed in accordance with the flexural deformation of the drive shaft, and the compressive load acting on the inner circumferential surface of the bearing portion is relaxed, thereby suppressing the occurrence of local wear.

However, in recent years, in view of energy saving and resource saving, the hermetic compressor is required to have a high speed of the cycle of suction, compression, and discharge and a high pressure of the working pressure of the refrigerant gas due to the spread of the variable speed compressor, and the amplitude of the pressure pulsation in the compression mechanism section becomes large before and after the refrigerant gas compressed by the compression mechanism section is discharged into the closed container in the hermetic compressor due to the high speed and the high pressure.

When the pressure pulsation in the compression mechanism portion becomes large, the drive shaft is pushed in the axial direction and relatively moves in the axial direction.

In order to enable eccentric rotation of the rotary plunger, a small gap is formed between the lower end surface of the upper bearing abutting against the cylinder and the upper end surface of the rotary plunger, and between the upper end surface of the lower bearing abutting against the cylinder and the lower end surface of the rotary plunger. Due to the relative movement of the drive shaft in the axial direction, one gap is expanded and the other gap is reduced.

When at least one of the upper bearing and the lower bearing is provided with a flexible structure, when a gap between the upper bearing and the rotary plunger and the lower bearing is enlarged, the refrigerant gas flows into the flexible structure groove through the gap. When the gap between the lower end surface of the upper bearing or the upper end surface of the lower bearing and the upper end surface or the lower end surface of the rotary plunger is reduced, the refrigerant gas is less likely to flow out of the flexible structure groove through the gap. As a result, pressure pulsation is repeatedly generated inside the flexible structure groove.

Since the pressure inside the flexible structural groove becomes a force acting in the axial direction on the bottom surface (top surface) of the flexible structural groove, when pulsation is increased, the force for relatively moving the drive shaft in the axial direction becomes stronger, and there is a problem that noise from the main body of the hermetic compressor increases or vibration of the main body increases.

Although there is a method of releasing the refrigerant gas inside the flexible structure groove, there is room for further improvement because the refrigerant gas is taken into the refrigerating machine oil at the place where the refrigerant gas is released, and the required refrigerating machine oil is reduced, and the lubricity and sealing property of the compression mechanism portion are lowered.

Disclosure of Invention

The present invention has been made to solve the above-described problems, and provides a hermetic compressor having a flexible structure that suppresses local wear of a drive shaft due to deflection of the drive shaft, and capable of suppressing increase in noise and vibration by reducing a force that causes the drive shaft to move relatively in the axial direction due to high speed of a compression mechanism and high pressure of refrigerant gas.

The hermetic compressor of the present invention includes, in a compression mechanism part thereof: a drive shaft coupled to the electric mechanism and transmitting a driving force; a cylinder block provided with a cylindrical cylinder chamber having an opening in an axial direction thereof, and configured to suck and compress a refrigerant gas; an upper bearing and a lower bearing each having a bearing hole through which the drive shaft is inserted, a bearing portion having a bearing hole for supporting the drive shaft, and a flange portion for closing an opening of the cylinder chamber; a discharge port provided in at least one of the upper bearing and the lower bearing, communicating the cylinder chamber and the outside of the cylinder chamber, and discharging the refrigerant gas compressed in the cylinder chamber; a discharge muffler provided on at least one of a side of the upper bearing opposite to the cylinder block and a side of the lower bearing opposite to the cylinder block; a muffler chamber from which the refrigerant gas is discharged from a discharge port to the muffler chamber between the discharge muffler and the upper bearing or between the discharge muffler and the lower bearing; and a flexible structure groove provided so as to surround at least one of a cylinder-side opening portion of the bearing hole of the upper bearing and a cylinder-side opening portion of the bearing hole of the lower bearing, opening on the cylinder side, and forming a thin-walled portion between the flexible structure groove and the bearing hole of the upper bearing or between the flexible structure groove and the bearing hole of the lower bearing,

the flexible structure groove is provided with a communication hole for communicating the flexible structure groove and the sound deadening chamber, and the refrigerant gas flowing into the flexible structure groove from the cylinder chamber is discharged into the sound deadening chamber.

In the hermetic compressor of the present invention, the flexible structure groove provided in at least one of the upper bearing and the lower bearing is provided with the communication hole communicating the flexible structure groove and the sound deadening chamber, and the refrigerant gas flowing into the flexible structure groove from the cylinder chamber is discharged into the sound deadening chamber, and therefore, the hermetic compressor is provided with the flexible structure and the flexible structure groove which suppress local wear of the drive shaft due to flexure of the drive shaft, and can suppress contact between the refrigerant gas discharged from the flexible structure groove through the communication hole and the refrigerant oil, and can alleviate a force which relatively moves the drive shaft in the axial direction due to the high speed of the compression mechanism portion and the high pressure of the refrigerant gas, thereby suppressing increase in noise and vibration.

Drawings

Fig. 1 is an explanatory view of the entire hermetic compressor according to embodiment 1 of the present invention.

Fig. 2 is an enlarged explanatory view of a compression mechanism unit according to embodiment 1 of the present invention.

Fig. 3 is a sectional view of a compression mechanism unit according to embodiment 1 of the present invention.

Fig. 4 is a perspective view of an upper bearing according to embodiment 1 of the present invention.

Fig. 5 is a perspective view of a lower bearing according to embodiment 1 of the present invention.

Fig. 6 is a plan view of the upper bearing according to embodiment 1 of the present invention.

Fig. 7 is an explanatory diagram of a refrigeration circuit according to embodiment 1 of the present invention.

Fig. 8 is a sectional view of the flexible structure of the upper bearing according to embodiment 1 of the present invention.

Detailed Description

Embodiment 1.

Fig. 1 is a sectional view of a hermetic rotary compressor according to embodiment 1 of the present invention, as viewed in the longitudinal direction, i.e., in the radial direction of a drive shaft. Fig. 2 is an enlarged view of the compression mechanism portion of fig. 1. Fig. 3 is a view seen from the axial direction by cutting with a-a of fig. 2, i.e., a plane perpendicular to the axial direction of the crankshaft, i.e., a cross-sectional view of the compression mechanism portion seen from the top surface.

As shown in fig. 1, the hermetic compressor 100 houses a compression mechanism unit 3 and an electric mechanism unit 2 above the compression mechanism unit 3 in a hermetic container 1. The electric mechanism 2 and the compression mechanism 3 are coupled by a drive shaft 4, and the compression mechanism 3 is driven by the electric mechanism 2. The electric mechanism 2 includes a stator 21 and a rotor 22, the rotor 22 is rotated by magnetic force generated by the stator 21, and the drive shaft 4 transmits rotational force of the electric mechanism 2 to the compression mechanism 3. The stator 21 includes a coil formed by winding a conductive wire, and generates a magnetic force by applying a current to the coil. The coil of the stator 21 is connected to a terminal 23 provided in the hermetic compressor 100, and is energized from the outside of the hermetic compressor 100 through the terminal 23. The rotor 22 includes a secondary conductor made of an aluminum bar or the like, a permanent magnet, and the like, and rotates in response to magnetic force generated by the coil of the stator 21.

The compression mechanism 3 compresses the low-pressure refrigerant gas sucked into the compression mechanism 3 by the driving force, which is the rotational force of the electric mechanism 2 transmitted from the drive shaft 4, and discharges the high-pressure refrigerant gas into the sealed container 1. The inside of the closed casing 1 becomes a high-pressure space due to the compressed high-temperature and high-pressure refrigerant gas. On the other hand, refrigerating machine oil for lubricating the compression mechanism 3 is stored in the bottom portion, which is the lower portion of the closed casing 1.

The drive shaft 4 is composed of a main shaft portion 41, a sub shaft portion 42, and an eccentric shaft portion 43, and is provided in the order of the main shaft portion 41, the eccentric shaft portion 43, and the sub shaft portion 42 along the axial direction. That is, the main shaft portion 41 is provided on one axial side of the eccentric shaft portion 43, and the sub shaft portion 42 is provided on the other axial side of the eccentric shaft portion 43. The main shaft portion 41, the auxiliary shaft portion 42, and the eccentric shaft portion 43 each have a substantially cylindrical shape, and are disposed coaxially such that the axial centers of the main shaft portion 41 and the auxiliary shaft portion 42 coincide with each other. On the other hand, the center of the axis of the eccentric shaft 43 is offset from the center of the axes of the main shaft 41 and the auxiliary shaft 42. When the main shaft portion 41 and the auxiliary shaft portion 42 rotate about the shaft center, the eccentric shaft portion 43 eccentrically rotates. The rotor 22 of the electric mechanism portion 2 is fixed to the main shaft portion 41 by shrink fitting or press fitting, and the cylindrical rotary plunger 32 is slidably attached to the eccentric shaft portion 43.

A cylindrical hollow hole is provided in the center of the shaft of the drive shaft 4, and this hollow hole serves as an oil supply path for transferring the refrigerating machine oil in the bottom of the sealed container 1. The oil supply passage has an opening portion at an axial end surface of the auxiliary shaft portion 42. The sub-shaft 42 side of the drive shaft 4 is immersed in the refrigerating machine oil stored in the bottom of the closed casing 1. When the drive shaft 4 rotates, the oil supply passage sucks the stored refrigerating machine oil from the opening of the auxiliary shaft portion 42. The sucked refrigerant oil is supplied to each sliding portion of the compression mechanism portion 3, and the compression mechanism portion 3 is lubricated and sealed.

As shown in fig. 2 and 3, the compression mechanism 3 includes a drive shaft 4, a cylinder block 31, a rotary plunger 32, an upper bearing 33, a lower bearing 34, and a vane 35. The cylinder block 31 is provided with a cylinder chamber 36 which is a cylindrical inner space having both axial ends opened. The cylinder chamber 36 of the cylinder block 31 houses an eccentric shaft portion 43 of the drive shaft 4 and a rotary plunger 32 attached to the eccentric shaft portion 43. The eccentric shaft portion 43, that is, the rotary plunger 32, eccentrically rotates in the cylinder chamber 36 of the cylinder block 31 by the rotation of the drive shaft 4.

The cylinder block 31 is provided with vane grooves 37 along the radial direction of the cylinder chamber 36, one of which opens into the cylinder chamber 36 and the other opens into the back pressure chamber 38. The blade groove 37 accommodates a blade 35 having a substantially rectangular parallelepiped shape, and the blade 35 reciprocates while sliding in the blade groove 37. A spring is provided in the back pressure chamber 38. The vane 35 is pushed out from the vane groove 37 to the cylinder chamber 36 of the cylinder block 31 by the refrigerant gas taken into the back pressure chamber 38 and the force of the spring. The tip of the vane 35 abuts against the rotary plunger 32. Thus, the vane 35 divides a space formed by the inner circumferential surface of the cylinder chamber 36 of the cylinder 31 and the outer circumferential surface of the rotary plunger 32 into a suction chamber and a compression chamber.

The rotary plunger 32 is annular, i.e., cylindrical, and is rotatably attached to the eccentric shaft portion 43. The rotary plunger 32 eccentrically rotates together with the eccentric shaft portion 43 in the cylinder chamber 36 by the rotation of the drive shaft 4. Thereby, the vane 35 abutting against the rotary plunger 32 reciprocates in the vane groove 37.

Although the rotary plunger 32 and the vane 35 have been described as separate shapes, they may be integrated into one body and operate substantially the same.

An upper bearing 33 for closing an upper opening portion, which is one of the axial directions of the cylinder chamber 36, is fixed to the upper surface of the cylinder block 31 by bolts. That is, the upper bearing 33 blocks the upper sides of the suction chamber and the compression chamber in the cylinder 31. Fig. 4 shows the upper bearing 33 as viewed from the cylinder block 31 side. As shown in fig. 4, the upper bearing 33 is composed of a cylindrical bearing portion 33a and a flat flange portion 33b. The flange portion 33b is a fixed portion fixed to the cylinder block 31 by a bolt, and closes one opening portion in the axial direction of the cylinder chamber 36, that is, the upper side of the suction chamber and the compression chamber in the cylinder block 31. The flange portion 33b is connected to, i.e., integrally connected to, the end portion of the cylindrical bearing portion 33a on the cylinder 31 side. The outermost edge of the flange portion 33b is disposed in the radial direction of the bearing portion 33a. The bearing portion 33a is provided upright on the flange portion 33b so that an end portion on the opposite side to the cylinder 31 side is arranged in the direction opposite to the cylinder 31 side from the flange portion 33b, that is, in the direction of the rotor 22. The bearing portion 33a has a bearing hole 33c, and the bearing hole 33c communicates between both ends of the bearing portion 33a in the axial direction, that is, from an end portion on the cylinder 31 side to an end portion on the opposite side of the cylinder 31. The opening of the bearing hole 33c is disposed on the side of the bearing portion 33a opposite to the cylinder 31 side and on the cylinder 31 side of the flange portion 33b. That is, the bearing holes 33c communicate with the inside of the bearing portion 33a, and the openings thereof are connected to each other. The bearing hole 33c has a cylindrical inner peripheral surface, through which the spindle portion 41 is inserted from one opening portion to the other opening portion, and the bearing portion 33a supports the spindle portion 41. That is, the upper bearing 33 rotatably supports the main shaft portion 41, i.e., the drive shaft 4, in the radial direction.

Further, a gap is provided between the cylindrical inner peripheral surface of the bearing hole 33c of the bearing portion 33a of the upper bearing 33 and the outer peripheral surface of the main shaft portion 41 of the drive shaft 4. I.e. assembled without touching each other. The refrigerant oil is supplied from the oil supply passage of the drive shaft 4 to the gap to form an oil film. Therefore, the bearing portion 33a of the upper bearing 33 rotatably supports the main shaft portion 41 of the drive shaft 4 in the radial direction via the refrigerating machine oil. Since the oil film is formed by the hydraulic pressure from the oil supply path of the drive shaft 4, the drive shaft 4 is supported by the hydraulic pressure of the oil film so that the inner peripheral surface of the bearing portion 33a does not contact the outer peripheral surface of the main shaft portion 41.

In fig. 4, reference numeral 33d denotes an oil groove for transferring the refrigerating machine oil to a gap between the inner peripheral surface of the bearing portion 33a and the outer peripheral surface of the main shaft portion 41, and reference numeral 33e denotes a bolt hole for fixing the upper bearing 33 to the cylinder 31.

Similarly, the lower bearing 34 that closes the lower opening portion, which is the other axial direction of the cylinder chamber 36, is fixed to the lower surface of the cylinder block 31 by bolts. That is, the suction chamber and the compression chamber in the cylinder 31 are closed at the lower side. Fig. 5 shows the lower bearing 34 as viewed from the cylinder block 31 side. As shown in fig. 5, the lower bearing 34 is composed of a cylindrical bearing portion 34a and a flat flange portion 34b. The flange portion 34b is a fixed portion fixed to the cylinder block 31 by a bolt, and blocks the other side in the axial direction of the cylinder chamber 36, that is, the lower side of the suction chamber and the compression chamber in the cylinder block 31. The flange portion 34b is connected, i.e., integrally connected, to the end of the cylindrical bearing portion 34a on the cylinder 31 side. The outermost edge of the flange portion 34b is disposed in the radial direction of the bearing portion 34a. The bearing portion 34a is provided upright on the flange portion 34b so that an end portion on the opposite side to the cylinder 31 side is arranged in the direction opposite to the cylinder 31 side from the flange portion 34b, that is, in the direction of the bottom portion of the closed casing 1. The bearing portion 34a has bearing holes 34c, and the bearing holes 34c communicate between both ends of the bearing portion 34a in the axial direction, that is, from the end on the cylinder 31 side to the end on the opposite side of the cylinder 31. The opening of the bearing hole 34c is disposed on the side of the bearing portion 34a opposite to the cylinder 31 side and on the cylinder 31 side of the flange portion 34b. That is, the bearing holes 34c communicate with the inside of the bearing portion 34a, and the openings thereof are connected to each other. The bearing hole 34c has a cylindrical inner peripheral surface, through which the auxiliary shaft portion 42 is inserted from one opening portion to the other opening portion, and the bearing portion 34a supports the auxiliary shaft portion 42. That is, the lower bearing 34 rotatably supports the sub shaft portion 42, i.e., the drive shaft 4, in the radial direction.

Further, a gap is provided between the cylindrical inner peripheral surface of the bearing hole 34c of the bearing portion 34a of the lower bearing 34 and the outer peripheral surface of the sub shaft portion 42 of the drive shaft 4. I.e. assembled without touching each other. The refrigerant oil is supplied from the oil supply passage of the drive shaft 4 to the gap to form an oil film. Therefore, the bearing portion 34a of the lower bearing 34 supports the sub-shaft portion 42 of the drive shaft 4 via the refrigerating machine oil. Since the oil film is formed by the hydraulic pressure from the oil supply path of the drive shaft 4, the drive shaft 4 is supported by the hydraulic pressure of the oil film so that the inner peripheral surface of the bearing portion 34a does not contact the outer peripheral surface of the sub shaft portion 42.

In fig. 5, reference numeral 34d denotes an oil groove for transferring the refrigerating machine oil to a gap between the inner peripheral surface of the bearing portion 34a and the outer peripheral surface of the main shaft portion 41, and reference numeral 34e denotes a bolt hole for fixing the lower bearing 34 to the cylinder 31.

In addition, fig. 1 and 2 show a case where there is one cylinder, and the description is given based on this case, but there is a case where there are two or more cylinders. In the case of multiple cylinders, a structure in which cylinders are stacked vertically is common. The upper bearing 33 closes an upper opening portion of the uppermost cylinder, and the lower bearing 34 closes a lower opening portion of the lowermost cylinder. An intermediate partition plate for partitioning the cylinder chambers from each other is provided between the cylinder block and the cylinder block. The opening portions other than the upper opening portion of the uppermost cylinder and the lower opening portion of the lowermost cylinder are closed by the intermediate partition plate. The upper bearing 33 and the lower bearing 34 have the same structure for shaft-supporting the drive shaft 4.

The cylinder 31 is provided with a flow path, i.e., a suction port, which communicates between the outside of the closed casing 1 and the cylinder chamber 36. The suction port is a hole provided in the cylinder 31 in a normal case. The suction port communicates with one of the suction chambers obtained by dividing the cylinder chamber 36 by the vane 35. The cylinder block 31 sucks the refrigerant gas from the outside of the sealed container 1 into the suction chamber in the cylinder chamber 36 through the suction port.

Similarly, a flow path, i.e., a discharge hole, is provided to communicate the outside of the cylinder block 31 and the cylinder chamber 36. The discharge hole is also a hole or a slit provided in the cylinder 31 in a normal case. The discharge hole communicates with the other compression chamber divided by the vane 35 into the cylinder chamber 36. Fig. 6 is a view of the upper bearing 33 as viewed from the upper surface. The upper bearing 33 is provided with a discharge port 51, which is a flow path and an opening portion communicating with the discharge port. A discharge valve 52 is provided in the discharge port 51. The discharge port 51 communicates the compression chamber of the cylinder 31 with the external space of the cylinder 31 via the discharge hole. The discharge valve 52 closes until the refrigerant gas in the compression chamber reaches a predetermined pressure, and opens when the refrigerant gas in the compression chamber reaches or exceeds the predetermined pressure. That is, the refrigerant gas compressed in the compression chamber in the cylinder chamber 36 is discharged to the outside of the cylinder chamber 36 through the discharge port 51 and the discharge hole.

In addition, the lower bearing 34 may have a discharge port. In this case, the discharge valve is provided, and the closing is performed until the refrigerant gas in the compression chamber reaches a predetermined pressure, and the opening is performed when the refrigerant gas in the compression chamber reaches the predetermined pressure or more.

The discharge port may be provided in both the upper bearing 33 and the lower bearing 34.

When the discharge port 51 is provided in the upper bearing 33, the upper discharge muffler 39 is provided in the upper bearing 33, and the upper discharge muffler 39 covers a surface of the upper bearing 33 opposite to the cylinder block 31, that is, a surface of the upper bearing 33 on which the main shaft portion 41 of the drive shaft 4 and the bearing portion 33a of the upper bearing 33 are disposed. The upper discharge muffler 39 may cover the entire surface of the upper bearing 33 opposite to the cylinder 31 or may cover a part of the surface. The upper discharge muffler 39 is attached to the upper bearing 33 by bolts or the like. A space, i.e., an upper sound-deadening chamber 39a is provided between the upper bearing 33 and the upper discharge muffler 39. That is, the upper discharge muffler 39 forms an upper sound-deadening chamber 39a with the upper bearing 33. Therefore, the discharge port 51 communicates the compression chamber, i.e., the cylinder chamber 36 and the muffler chamber 39a, by opening and closing the discharge valve 52. The refrigerant gas discharged from the discharge port 51 of the upper bearing 33 is diffused in the upper muffling chamber 39a. The discharge sound is suppressed by temporarily diffusing the refrigerant gas compressed in the cylinder 31 into the upper muffling chamber 39a.

In addition, in the case where the discharge port is located at the lower bearing 34, the lower discharge muffler 40 is provided at the lower bearing 34. The lower discharge muffler 40 also covers the surface of the lower bearing 34 on the side opposite to the cylinder block 31, that is, the surface on the side where the auxiliary shaft portion 42 of the drive shaft 4 and the bearing portion 34a of the lower bearing 34 are disposed. The lower discharge muffler 40 may cover the entire surface of the lower bearing 34 on the side opposite to the cylinder block 31, or may cover a part thereof. The lower discharge muffler 40 is attached to the lower bearing 34 by bolts or the like. A space, i.e., a lower sound-deadening chamber 40a is provided between the lower bearing 34 and the lower discharge muffler 40. That is, the lower discharge muffler 40 forms a lower sound-deadening chamber 40a between itself and the lower bearing 34. The discharge port communicates the cylinder chamber 36, which is a compression chamber, with the sound-deadening chamber 40a by opening and closing the discharge valve. Then, the refrigerant gas diffuses from the discharge port of the lower bearing 34 into the lower sound-deadening chamber 40a of the lower discharge muffler 40. The refrigerant gas discharged to the lower muffling chamber 40a is guided to the upper bearing 33 side through a communication passage provided in the upper bearing 33, the lower bearing 34, and the cylinder block 31.

In addition, in the case where the discharge ports are provided in both of the upper bearing 33 and the lower bearing 34 as shown in fig. 1 and 2, an upper discharge muffler 39 and a lower discharge muffler 40 are provided, respectively. Then, the refrigerant gas is discharged into the upper sound-deadening chamber 39a and the lower sound-deadening chamber 40a, respectively. The refrigerant gas discharged to the lower muffling chamber 40a is guided to the upper muffling chamber 39a through a communication passage provided in the cylinder 31.

In the case of multiple cylinders, both the upper discharge muffler 39 and the lower discharge muffler 40 are provided. The upper bearing blocks an opening portion above the uppermost cylinder block, and the lower bearing blocks an opening portion below the lowermost cylinder block. The refrigerant gas compressed in each cylinder chamber is discharged from the discharge ports of the upper bearing and the lower bearing. Therefore, the upper bearing and the lower bearing are provided with an upper discharge muffler and a lower discharge muffler, respectively. The refrigerant gas discharged to the lower muffling chamber is guided to the upper muffling chamber through a communication passage provided in the cylinder.

In the upper discharge muffler 39, an opening is provided above the upper sound-deadening chamber 39a, and the upper sound-deadening chamber 39a and a space between the upper discharge muffler 39 and the closed casing 1, that is, an internal space of the closed casing 1 communicate with each other. Thereby, the refrigerant gas compressed in the cylinder chamber 36 is discharged into the closed casing 1 through the upper discharge muffler 39.

The refrigerant gas discharged into the sealed container 1 is guided in the direction of a discharge pipe 5 located above the sealed container 1, and is sent out of the sealed container 1 from the discharge pipe 5. At this time, the refrigerant gas passes through a gap between the stator 21 and the rotor 22 of the electric mechanism 2 or a communication hole provided in the rotor 22, and is sent upward.

Suction muffler 101 provided outside sealed container 1 is connected to the suction port via suction pipe 6. The low-pressure refrigerant gas and the liquid refrigerant are sent to the hermetic compressor 100 in a mixed state from the external circuit to which the hermetic compressor 100 is connected. Since the liquid refrigerant flows into the compression mechanism 3 and is compressed, which causes a failure of the compression mechanism 3, the suction muffler 101 separates the liquid refrigerant from the refrigerant gas and sends only the refrigerant gas to the compression mechanism 3.

As shown in fig. 7, a condenser 102, an expansion valve 103, and an evaporator 104 are provided outside the hermetic compressor 100 to form a refrigeration circuit. That is, an annular circuit is formed which is connected to the suction muffler 101 through a pipe from the discharge pipe 5 of the hermetic compressor 100 via the condenser 102, the expansion valve 103, and the evaporator 104, and a refrigeration cycle for carrying thermal energy is formed by circulating a refrigerant in the circuit to exchange heat with air, water, and the like. Thus, a heat pump device using this cycle is realized.

Next, the operation of the compression mechanism 3 will be described.

First, a low-pressure low-temperature refrigerant gas is sucked into a suction chamber communicating with a suction port. The suction chamber into which the refrigerant gas is sucked moves in the cylinder chamber 36 by the eccentric rotation of the rotary plunger 32, i.e., the eccentric shaft portion 43, and communication with the suction port is blocked. When the rotary plunger 32 further eccentrically rotates, the volume of the suction chamber is reduced, and the sucked refrigerant gas is compressed. That is, the suction chamber becomes a compression chamber. The compression chamber communicates with the discharge hole as the eccentric rotation of the rotary plunger 32 advances. When the compression chamber communicates with the discharge hole and the refrigerant gas reaches a predetermined pressure, the discharge valve 52 closing the discharge hole and the discharge port 51 opens. When the discharge port 51 is opened, the high-pressure and high-temperature refrigerant gas in the compression chamber is discharged into the discharge mufflers 39 and 40 through the discharge port 51. The refrigerant gas discharged into the discharge mufflers 39 and 40 is discharged into the closed casing 1 from the discharge mufflers 39 and 40. When the rotary plunger 32 continues to rotate eccentrically, the communication with the discharge hole is interrupted, and the communication with the suction port is resumed. By repeating this process, the compression mechanism 3 sucks, compresses, and discharges the refrigerant gas. This series of operations is performed during one rotation of the rotary plunger 32 in the cylinder chamber 36.

Due to such a structure and operation, when the refrigerant gas is compressed in the compression mechanism portion 3, a compression load acts on the drive shaft 4, and the drive shaft 4 undergoes flexural deformation.

When the refrigerant gas is compressed in the compression chamber of the compression mechanism portion 3, a compression load of the compressed refrigerant gas in the compression chamber is applied to the eccentric shaft portion 43 of the drive shaft 4. For example, in fig. 3, assuming that the rotary plunger 32 rotates counterclockwise, the discharge hole and the discharge port 51 are arranged on the right side of the vane groove. Due to the compression load of the refrigerant gas, the drive shaft 4 is pressed in the direction opposite to the direction in which the discharge port 51 is disposed, that is, in the lower left direction of the drawing, around the center of the inner diameter of the cylinder 31. Since the main shaft portion 41 is pressed by the upper bearing 33 and the sub shaft portion 42 is pressed by the lower bearing 34, the drive shaft 4 is subjected to flexural deformation with these as fulcrums.

Since the drive shaft 4 is subjected to flexural deformation with the upper bearing 33 and the lower bearing 34 as fulcrums, strong local contact may be formed in the vicinity of the connection portion between the main shaft portion 41 and the eccentric shaft portion 43, in the vicinity of the connection portion between the sub shaft portion 42 and the eccentric shaft portion 43, and in the vicinity of the end portions of the upper bearing 33 and the lower bearing 34 on the cylinder block 31 side. As a result, damage may be brought about.

To prevent this, as shown in fig. 4 and 5, an upper flexible structure groove 61 and an upper flexible structure 62 are provided on the cylinder 31 side surface of the upper bearing 33, and a lower flexible structure groove 64 and a lower flexible structure 65 are provided on the cylinder 31 side surface of the lower bearing 34. The upper flexible structure groove 61 and the upper flexible structure 62, and the lower flexible structure groove 64 and the lower flexible structure 65 are slightly deformed in response to the flexural deformation of the drive shaft 4, thereby slightly deforming the inner diameters of the bearing holes 33c, 34c of the main shaft portion 41 and the sub shaft portion 42. As a result, local contact in the vicinity of the connection portion between the main shaft portion 41 and the eccentric shaft portion 43, the vicinity of the connection portion between the sub shaft portion 42 and the eccentric shaft portion 43, and the vicinity of the end portions of the upper bearing 33 and the lower bearing 34 on the cylinder block 31 side is alleviated.

In addition, at least one of the upper flexible structure groove 61 and the upper flexible structure 62, and the lower flexible structure groove 64 and the lower flexible structure 65 may be provided.

The upper flexible structure groove 61 is an annular groove that annularly surrounds an opening portion of the bearing hole 33c of the bearing portion 33a of the upper bearing 33 that opens on the cylinder 31 side. The upper flexible structure groove 61 is provided in a circular shape concentric with the center of the opening portion of the bearing hole 33c, and opens on the cylinder 31 side. The upper flexible structure 62 is a cylindrical thin portion disposed between the upper flexible structure groove 61 and the bearing hole 33c and formed by the upper flexible structure groove 61 and the inner peripheral surface of the bearing hole 33c. The upper flexible construct 62 is easily deformable and has a spring force. That is, the elastic member is formed to have a thickness capable of elastic deformation. The upper flexible structure groove 61 is formed to have a groove width of a degree not to hinder the elastic deformation of the upper flexible structure 62 and a depth of a degree to allow the upper flexible structure 62 to elastically deform. For example, the thickness of the flexible structure may be about several mm, the width of the groove may be narrower than the thickness of the flexible structure, and the depth of the groove may be about several mm to ten and several mm.

The lower flexible structure groove 64 is an annular groove that annularly surrounds an opening portion of the bearing hole 34c of the bearing portion 34a of the lower bearing 34 that opens on the cylinder 31 side. The lower flexible structure groove 64 is provided in a circular shape concentric with the center of the opening portion of the bearing hole 34c, and opens on the cylinder 31 side. The lower flexible structure 65 is a cylindrical thin portion disposed between the lower flexible structure groove 64 and the bearing hole 34c and formed by the lower flexible structure groove 64 and the inner peripheral surface of the bearing hole 34c. The lower flexible construct 65 is easily deformable and has a spring force. That is, the elastic member is formed to have a thickness capable of elastic deformation. In addition, the lower flexible structure groove 64 is formed with a width of the groove to such an extent that elastic deformation of the lower flexible structure 65 is not hindered, and with a depth to such an extent that the lower flexible structure 65 has elastic deformation. The depth and the like are the same as the upper flexible formation groove 61 and the upper flexible formation 62.

In recent years, however, hermetic compressor 100 is required to increase the speed of the cycle of suction, compression, and discharge and to increase the working pressure of the refrigerant gas. In particular, a refrigerant having a low GWP (Global Warming Potential) is required, and as a result, a refrigerant having a lower density than that of the conventional refrigerant 410A and a refrigerant used under high pressure are required. Due to the high speed of the compression mechanism 3 and the high pressure of the refrigerant gas, the amplitude of the pressure pulsation of the compression chamber increases before and after the refrigerant gas compressed by the compression mechanism 3 is discharged into the closed casing 1 in the hermetic compressor 100.

When the pressure pulsation in the compression chamber increases, the drive shaft 4 is pushed in the axial direction and moves relatively in the axial direction.

In order to enable eccentric rotation of the rotary plunger 32, a small gap is formed between the surface of the upper bearing 33 on the cylinder 31 side and the end surface of the rotary plunger 32 on the upper bearing 33 side, and between the surface of the lower bearing 34 on the cylinder 31 side and the end surface of the rotary plunger 32 on the lower bearing 34 side. In general, each gap is sealed by the refrigerating machine oil, and airtightness between the compression chamber and the suction chamber is maintained. When the behavior in which the drive shaft 4 relatively moves in the axial direction occurs, one gap expands and the other gap contracts. When the gap is enlarged, the sealing function of the refrigerating machine oil is also reduced.

When the upper bearing 33 and the lower bearing 34 are provided with the upper flexible structure groove 61 and the upper flexible structure 62, and at least one of the lower flexible structure groove 64 and the lower flexible structure 65, the refrigerant gas flows into at least one of the upper flexible structure groove 61 and the lower flexible structure groove 64 through an enlarged gap between at least one of the end surface of the upper flexible structure 62 on the cylinder 31 side and the end surface of the lower flexible structure 65 on the cylinder 31 side, and at least one of the end surface of the rotary plunger 32 on the upper bearing 33 side and the end surface of the lower bearing 34 side. On the other hand, if the gap between at least one of the end surface of the upper flexible structure 62 on the cylinder 31 side and the end surface of the lower flexible structure 65 on the cylinder 31 side and at least one of the end surface of the rotary plunger 32 on the upper bearing 33 side and the end surface of the lower bearing 34 side is reduced, the fluid is less likely to flow out of the upper flexible structure groove 61 or the lower flexible structure groove 64 from the inside of at least one of the upper flexible structure groove 61 and the lower flexible structure groove 64. As a result, pressure pulsation is repeated also in at least one of the upper flexible structural groove 61 and the lower flexible structural groove 64.

Therefore, the pressure inside the upper flexible structure groove 61 or the lower flexible structure groove 64 becomes an axial force acting on the bottom surface (top surface) of the upper flexible structure groove 61 or the lower flexible structure groove 64. When the pulsation is large, the force for relatively moving the drive shaft 4 in the axial direction is large, and noise from the main body of the hermetic compressor 100 increases or vibration of the main body increases.

In order to avoid this, a flow path may be provided for releasing the refrigerant gas at high pressure from the inside of the upper flexible structure groove 61 and the lower flexible structure groove 64 to the outside of the upper flexible structure groove 61 and the lower flexible structure groove 64.

For example, there is the following structure: the flange portion 33b of the upper bearing 33 is provided with a communication hole that opens to the end surface of the outermost edge portion in the radial direction with the center of the bearing hole 33c of the upper bearing 33 as a starting point and communicates the opening portion thereof with the upper flexible structure groove 61, or the flange portion 34b of the lower bearing 34 is provided with a communication hole that opens to the end surface of the outermost edge portion in the radial direction with the center of the bearing hole 34c of the lower bearing 34 as a starting point and communicates the opening portion thereof with the lower flexible structure groove 64. The refrigerant gas in the upper flexible structural groove 61 or the lower flexible structural groove 64 can be discharged into the sealed container 1 through the communication hole. However, the refrigerant oil is stored in the closed casing 1 to such an extent that the flange portion 33b of the upper bearing 33 is immersed therein. Therefore, when the high-pressure refrigerant gas is discharged from the upper flexible structural groove 61 or the lower flexible structural groove 64 through the communication hole, the refrigerant gas is released into the refrigerating machine oil. In such a case, the refrigerant oil is stirred by the refrigerant gas, and the refrigerant gas and the refrigerant oil are in a compatible state. The refrigerant gas is brought into the refrigerating machine oil, rises upward of the sealed container 1 by its mass, and is sent out to the refrigerating circuit outside the sealed container 1 from the discharge pipe 5.

When the refrigerating machine oil flows into the refrigeration circuit, the refrigerating machine oil interferes with heat exchange of the refrigeration cycle, and the heat exchange rate of the refrigeration circuit is reduced, thereby deteriorating the performance of the refrigeration circuit.

When the refrigerating machine oil is discharged from the closed casing 1, the refrigerating machine oil in the closed casing 1 decreases. This reduces the sealing performance of the compression mechanism 3, and reduces the airtightness. This increases leakage of the refrigerant gas from the compression mechanism 3, and deteriorates the compression performance. Further, the lubricity of each sliding portion is also reduced, which causes wear and damage. That is, the performance in the case of achieving higher speeds of the hermetic compressor 100 is difficult to maintain because the speed of the compression mechanism 3 of the hermetic compressor 100 is increased.

Further, in the communication hole communicating from the upper flexible structure groove 61 of the upper bearing 33 to the outermost edge portion of the flange portion 33b of the upper bearing 33 or the communication hole communicating from the lower flexible structure groove 64 of the lower bearing 34 to the outermost edge portion of the flange portion 34b of the lower bearing 34, since the communication hole has a length dimension, it is necessary to consider that the pressure loss of the communication hole and the clogging due to sludge, etc. which do not hinder the refrigerant gas from being discharged from the upper flexible structure groove 61 or the lower flexible structure groove 64 are complicated in design method and processing method. In particular, when the refrigerant is used at a higher pressure than a conventional refrigerant, it is important that the pressure loss does not interfere with the discharge of the refrigerant gas.

Therefore, there is room for further improvement in the method of releasing the gas from the upper flexible structure groove 61 of the upper bearing 33 to the end surface of the outermost edge portion of the flange portion 33b of the upper bearing 33 or from the lower flexible structure groove 64 of the lower bearing 34 to the end surface of the outermost edge portion of the flange portion 34b of the lower bearing 34 into the sealed container 1 for increasing the speed and the pressure of the sealed compressor 100.

In addition, there is also a structure as follows: the upper flexible formation 62 of the upper bearing 33 or the lower flexible formation 65 of the lower bearing 34 is provided with a cut-out. The refrigerant gas in the upper flexible structure groove 61 or the lower flexible structure groove 64 can be released from the notch toward the drive shaft 4. However, when the refrigerant gas is discharged toward the drive shaft 4, the refrigerant gas passes through the gap between the inner peripheral surface of the bearing hole 33c of the upper bearing 33 or the inner peripheral surface of the bearing hole 34c of the lower bearing 34 and the outer peripheral surface of the drive shaft 4, and is discharged into the sealed container 1. Therefore, the refrigerant gas is released into the oil film of the refrigerating machine oil formed in the gap between the inner peripheral surface of the bearing hole 33c of the upper bearing 33 or the inner peripheral surface of the bearing hole 34c of the lower bearing 34 and the outer peripheral surface of the drive shaft 4. Similarly to the case where the opening portions of the communication holes are provided in the end face of the outermost edge portion of the flange portion 33b of the upper bearing 33 and the end face of the outermost edge portion of the flange portion 34b of the lower bearing 34, the refrigerant gas is taken into the refrigerant oil and sent to the outside of the sealed container 1, which causes deterioration in performance of the refrigerant circuit, reduction in sealability of the compression mechanism portion 3, and reduction in lubricity of each sliding portion.

When the refrigerant gas in the upper flexible structural groove 61 or the lower flexible structural groove 64 passes through the gap between the inner peripheral surface of the bearing hole 33c of the upper bearing 33 or the bearing hole 34c of the lower bearing 34 and the outer peripheral surface of the drive shaft 4, the oil film in the gap is broken, and therefore the supporting force and the lubricity of the upper bearing 33 and the lower bearing 34 are reduced, which causes wear and damage. In particular, when used at a higher speed or a higher pressure than conventional refrigerants, a large load is applied to the upper bearing 33 and the lower bearing 34 that support the drive shaft 4, and therefore it is important to maintain an oil film that does not cause excessive wear or damage to these components.

Therefore, the method of providing the notch in the upper flexible structure 62 of the upper bearing 33 or the lower flexible structure 65 of the lower bearing 34 and discharging the refrigerant gas in the upper flexible structure groove 61 or the lower flexible structure groove 64 to the drive shaft 4 side has room for further improvement in terms of high speed and high pressure of the hermetic compressor 100.

In the present application, the opening of the communication hole communicating with the upper flexible structural groove 61 is provided on the side of the upper bearing 33 opposite to the cylinder 31, that is, on the side of the upper discharge muffler 39, and the opening of the communication hole communicating with the lower flexible structural groove 64 is provided on the side of the lower bearing 34 opposite to the cylinder 31, that is, on the side of the lower discharge muffler 40. That is, the communication hole of the upper flexible structure groove 61 communicates the upper flexible structure groove 61 with the upper sound-deadening chamber 39a, and the communication hole of the lower flexible structure groove 64 communicates the lower flexible structure groove 64 with the lower sound-deadening chamber 40a. Thereby, the refrigerant gas in the upper flexible structural groove 61 is discharged into the upper sound-deadening chamber 39a, and the refrigerant gas in the lower flexible structural groove 64 is discharged into the lower sound-deadening chamber 40a. Since the inside of the upper muffling chamber 39a and the inside of the lower muffling chamber 40a are filled with the compressed refrigerant gas discharged from the compression chamber of the cylinder 31, the refrigerant oil does not flow into the chambers and the refrigerant oil does not stir in the refrigerant gas. That is, when the refrigerant gas is discharged from the upper flexible structure groove 61 and the lower flexible structure groove 64, the refrigerant gas is not brought into the refrigerating machine oil. This can suppress the refrigerant oil from being sent to the outside of the sealed container 1.

Further, the refrigerant gas discharged from the upper flexible structural groove 61 or the lower flexible structural groove 64 does not pass through the gap between the inner peripheral surface of the bearing hole 33c of the upper bearing 33 or the bearing hole 34c of the lower bearing 34 and the outer peripheral surface of the drive shaft 4, and therefore does not affect the oil film in the gap, and the bearing force and the lubricity of the upper bearing 33 and the lower bearing 34 are not lowered.

However, although there is no inflow of the refrigerating machine oil into the upper muffling chamber 39a or the lower muffling chamber 40a, the excessive refrigerating machine oil is discharged from the sliding portion, and therefore, the excessive refrigerating machine oil slightly remains in the upper muffling chamber 39a or the lower muffling chamber 40a. It is necessary that the surplus refrigerant oil is not stirred into the refrigerant gas discharged from the upper flexible structure tank 61 or the lower flexible structure tank 64.

The interior of the upper muffling chamber 39a or the lower muffling chamber 40a is filled with refrigerant gas discharged from the compression chamber of the cylinder 31. If the communication hole communicating with the upper flexible structure groove 61 or the lower flexible structure groove 64 opens in the upper sound-deadening chamber 39a or the lower sound-deadening chamber 40a, there is a possibility that the refrigerant gas in the upper flexible structure groove 61 or the lower flexible structure groove 64 is sucked into the upper flexible structure groove 61 or the lower flexible structure groove 64 while the refrigerant gas in the upper flexible structure groove 61 or the lower flexible structure groove 64 is discharged into the upper sound-deadening chamber 39a or the lower sound-deadening chamber 40a. In the case of suction, since the suction loss is caused, it is necessary to prevent suction.

A method for achieving these problems in consideration will be described.

Fig. 8 is an enlarged sectional view of the upper bearing 33 of fig. 1 and 2. Reference numeral 63 denotes a communication hole, i.e., an exhaust hole, which communicates with the upper flexible structure groove 61 and opens in the upper sound-deadening chamber 39a. Reference numeral 61a denotes an opening portion of the upper flexible structure groove 61 that opens on the cylinder 31 side, and reference numeral 61b denotes a bottom portion (top portion) that is the deepest portion of the upper flexible structure groove 61 located on the opposite side of the upper flexible structure groove 61 from the reference numeral 61a. The lower bearing 34 also has the same structure as that of the lower bearing, and corresponds to the communication hole 66 in fig. 1 and 2.

Since the upper bearing 33 and the lower bearing 34 have the same structure, fig. 8 describes the structure of the upper bearing 33 as a representative. The communication hole 63 of the upper flexible configuration groove 61 is opened at the deepest portion 61b of the upper flexible configuration groove 61. Since the refrigerant gas is pressed toward the deepest portion 61b side of the upper flexible structural groove 61, the discharge effect is high. However, even if the structure in which the deepest portion 61b of the upper flexible structural groove 61 opens cannot be realized due to the strength design or the like of the upper flexible structure 62, the side surface on the deepest portion 61b side of the middle between the opening portion 61a of the upper flexible structural groove 61 and the deepest portion 61b of the upper flexible structural groove 61 may be opened. With this structure, the discharge of the refrigerant gas from the upper flexible structure groove 61 is not hindered.

As shown in fig. 8, the communication hole 63 of the upper flexible structure groove 61 is opened in the outer circumferential surface of the upper bearing 33 on the upper discharge muffler 39 side at a position where the bearing portion 33a of the upper bearing 33 is connected to, i.e., connected to, the flange portion 33b and bent in an L-shape when viewed from the radial direction of the bearing portion 33a. This allows the upper flexible structure groove 61 and the upper sound-deadening chamber 39a to communicate with each other at the shortest distance, and facilitates processing.

Further, the opening of the opening communication hole 63 of the upper flexible structure groove 61 is disposed above the plane of the flange portion 33b of the upper bearing 33 on the upper discharge muffler 39 side, which is also advantageous in terms of stirring of the refrigerating machine oil. For example, even if an excessive amount of the refrigerating machine oil remains in the sliding portion in the upper sound-deadening chamber 39a, the refrigerating machine oil is located on the plane of the flange portion 33b and is spaced apart from the opening portion of the communication hole 63. Therefore, the refrigerant gas discharged from the communication hole 63 of the upper flexible structural groove 61 does not stir the refrigerant oil.

As shown in fig. 6, the communication hole 63 of the upper flexible structure groove 61 opens on the discharge port 51 side and in the vicinity of the discharge port 51 with respect to the drive shaft 4. The vicinity of the discharge port 51 serves as a compression chamber, and the refrigerant gas is compressed or discharged. Since the refrigerant gas flows into the upper flexible structural groove 61 from the compression chamber, it is most effective to discharge the refrigerant gas from the upper flexible structural groove 61 to the outside of the upper flexible structural groove 61, that is, the upper muffler chamber 39a, in order to suppress the pulsation of the compression. Thus, the communication hole 63 of the upper flexible structural groove 61 opens on the discharge port 51 side, and the refrigerant gas can be discharged from the upper flexible structural groove 61 most efficiently to suppress the pulse of compression.

Further, the upper muffling chamber 39a is filled with the refrigerant gas from the discharge port 51, but the refrigerant gas discharged from the discharge port 51 and the refrigerant gas discharged from the upper flexible structural groove 61 are both the same refrigerant gas of the compression chamber. Therefore, the refrigerant gas having almost the same pressure is discharged, and the opening of the communication hole 63 of the upper flexible structural groove 61 is opened toward the discharge port 51, so that the refrigerant gas in the upper sound-deadening chamber 39a is not sucked into the upper flexible structural groove 61, and the discharge of the refrigerant gas is not hindered.

Since the excessive refrigerating machine oil and the like do not stay near the discharge port 51 due to the discharged high-pressure refrigerant gas, the refrigerant gas discharged from the communication hole 63 of the upper flexible structural groove 61 does not contact the refrigerating machine oil by opening the opening of the communication hole 63 of the upper flexible structural groove 61 to the discharge port 51 side, and the effect is further enhanced.

Further, the opening of the communication hole 63 of the upper flexible structure groove 61 is opened at a position above the discharge port 51, and thus a more advantageous structure is obtained in which the refrigerant gas does not contact the refrigerating machine oil.

The communication hole 63 of the upper flexible structural groove 61 may not be circular in cross section, but may be cut by a surface perpendicular to the direction from the opening of the upper flexible structural groove 61 of the communication hole 63 to the opening of the upper sound-deadening chamber 39a. For example, the shape may be an ellipse, an oblong, or a polygon. The shape of the opening of the upper sound-deadening chamber 39a and the shape of the opening of the upper flexible structure groove 61 are the same. The communication hole 63 may have a cross-sectional area that is almost the same from the opening of the upper flexible structure groove 61 to the opening of the upper sound-deadening chamber 39a, but even if the opening is tapered or chamfered and the cross-sectional area is increased, the function is not impaired.

In addition, the communication hole 63 of the upper flexible structural groove 61 is provided in a substantially linear shape from the upper flexible structural groove 61 to the opening of the upper sound-deadening chamber 39a in order to suppress pressure loss in the communication hole 63 of the upper flexible structural groove 61.

In addition, a plurality of communication holes 63 of the upper flexible structure groove 61 may be provided. When a plurality of the flexible structure grooves 61 are provided, the pressure loss of the discharged refrigerant gas can be reduced at one time, and the refrigerant gas can be smoothly discharged from the upper flexible structure groove 61.

In the case where a plurality of communication holes 63 are provided in the upper flexible structure groove 61, at least one of them may be provided on the discharge port 51 side. The remainder may be arranged in any direction. At least one communication hole 63 on the discharge port 51 side is provided to exhibit the above-described effects. In addition, in the case where a plurality of communication holes 63 are provided, even if some of the communication holes 63 are clogged with sludge or the like, the other communication holes 63 discharge the refrigerant gas, and therefore, the function of discharging the refrigerant gas from the upper flexible structural groove 61 is not impaired, redundancy is provided, and higher reliability can be ensured.

The upper flexible structure groove 61, the upper flexible structure 62, and the communication hole 63 of the upper bearing 33 have been described above. The communication holes 66 of the lower bearing 34, which are vertically opposite, are not necessarily equivalent in terms of the effects obtained by the vertical arrangement, but are almost the same with respect to the other points.

With the above configuration, by providing at least one of the upper flexible structure groove 61 and the communication hole 63 communicating the upper flexible structure groove 61 and the upper sound-deadening chamber 39a, and the lower flexible structure groove 64 and the communication hole 66 communicating the lower flexible structure groove 64 and the lower sound-deadening chamber 40a, the refrigerant gas flowing into at least one of the inside of the upper flexible structure groove 61 and the inside of the lower flexible structure groove 64 can be discharged to the outside of the upper flexible structure groove 61 or the outside of the lower flexible structure groove 64, that is, the upper sound-deadening chamber 39a or the lower sound-deadening chamber 40a. This reduces the pulsation of the pressure in the upper flexible structural groove 61 and the lower flexible structural groove 64, and suppresses the force that moves the drive shaft 4 relative to each other in the axial direction, thereby suppressing noise and vibration from the main body of the hermetic compressor 100.

In addition, the functions of the conventional upper flexible structure 62 and lower flexible structure 65 can be realized without being impaired.

Further, the opening of the communication hole 63 of the upper flexible structural groove 61 is opened into the upper sound-deadening chamber 39a, and the opening of the communication hole 66 of the lower flexible structural groove 64 is opened into the lower sound-deadening chamber 40a, so that the refrigerant gas discharged does not stir the refrigerant oil. This suppresses the refrigerant oil from being sent to the outside of the closed casing 1, which may deteriorate the performance of the refrigeration circuit, reduce the sealing performance of the compression mechanism 3, or reduce the lubricity of each sliding portion.

Further, since the refrigerant gas in the upper flexible structure groove 61 and the lower flexible structure groove 64 is discharged to the upper muffling chamber 39a or the lower muffling chamber 40a, the oil film in the bearing hole 33c of the upper bearing 33 or the bearing hole 34c of the lower bearing 34 is not affected. That is, wear and damage of the drive shaft 4 and the upper and lower bearings 33 and 34 are suppressed.

The communication hole 63 of the upper flexible structure groove 61 is opened in the outer circumferential surface of the upper discharge muffler 39 side at a position where the bearing portion 33a of the upper bearing 33 is connected to the flange portion 33b, i.e., at a position where the upper bearing portion 33a is connected to the flange portion and bent in an L-shape when viewed in the radial direction of the bearing portion 33a. The upper flexible structure groove 61 and the upper sound-deadening chamber 39a can communicate with each other at the shortest distance, and the processing is also easy.

Similarly, the communication hole 66 of the lower flexible structure groove 64 is opened in the outer peripheral surface of the lower discharge muffler 40 side at a position where the bearing portion 34a of the lower bearing 34 is connected to the flange portion 34b, i.e., connected to each other, and bent in an L-shape when viewed from the radial direction of the bearing portion 34a. The lower flexible structure groove 64 and the lower sound-deadening chamber 40a can communicate with each other at the shortest distance, and the processing is also easy.

Further, since the opening is formed upward of the flat surface of the flange portion 33b on the upper discharge muffler 39 side, even if an excessive amount of the refrigerating machine oil remains in the upper sound-deadening chamber 39a, the refrigerating machine oil is not stirred by the refrigerant gas discharged from the communication hole 63 of the upper flexible structural groove 61.

The opening of the communication hole 63 of the upper flexible structural groove 61 and the opening of the communication hole 66 of the lower flexible structural groove 64 are provided in the vicinity of a discharge port where the high-pressure refrigerant gas discharged does not accumulate the refrigerant oil. This prevents the refrigerant gas discharged from the communication holes 63 and 66 of the upper and lower flexible structural grooves 61 and 64 from contacting the refrigerating machine oil, thereby providing a higher effect.

The opening of the communication hole 63 of the upper flexible structural groove 61 is opened above the discharge port. The opening of the communication hole 66 of the lower flexible structure groove 64 is opened below the discharge port. That is, the opening of the communication hole 63 of the upper flexible structure groove 61 and the opening of the communication hole 66 of the lower flexible structure groove 64 are open to the end opposite to the cylinder 31 with respect to the flange portion 33b of the upper bearing 33 or the flange portion 34b of the lower bearing 34 in the bearing portion 33a of the upper bearing 33 or the bearing portion 34a of the lower bearing 34. Since the refrigerant oil is pushed out by the high-pressure refrigerant gas discharged from the discharge port, the refrigerant gas discharged from the communication hole 63 of the upper flexible structural groove 61 or the communication hole 66 of the lower flexible structural groove 64 and the refrigerant oil are more favorably configured so as not to contact each other.

Further, by providing the opening of the communication hole 63 of the upper flexible structural groove 61 and the opening of the communication hole 66 of the lower flexible structural groove 64 on the discharge outlet side or in the vicinity of the discharge outlet with respect to the drive shaft 4, the refrigerant gas flowing from the compression chamber during compression or discharge to the upper flexible structural groove 61 or the lower flexible structural groove 64 can be discharged from the inside of the upper flexible structural groove 61 and the inside of the lower flexible structural groove 64 to the outside of the upper flexible structural groove 61 or the outside of the lower flexible structural groove 64, that is, the upper sound-deadening chamber 39a or the lower sound-deadening chamber 40a. This can most effectively suppress the pulsation of the upper flexible structural groove 61 or the lower flexible structural groove 64.

The refrigerant gas discharged from the discharge port and the refrigerant gas discharged from the upper flexible structure groove 61 and the lower flexible structure groove 64 are both the same refrigerant gas of the compression chamber and are refrigerant gases having almost the same pressure. This prevents the refrigerant gas in the upper sound-deadening chamber 39a from being sucked into the upper flexible structural groove 61 from the communication hole 63 of the upper flexible structural groove 61 or the refrigerant gas in the lower sound-deadening chamber 40a from being sucked into the lower flexible structural groove 64 from the communication hole 66 of the lower flexible structural groove 64, and thus prevents the discharge of the refrigerant gas from being hindered.

Further, a plurality of the communication holes 63 of the upper flexible structural groove 61 or the communication holes 66 of the lower flexible structural groove 64 may be provided, so that the pressure loss of the discharged refrigerant gas can be reduced at one time. This enables the refrigerant gas to be smoothly discharged from the upper flexible structure groove 61 or the lower flexible structure groove 64.

When a plurality of discharge ports are provided, at least one discharge port is provided on the discharge port side, whereby the above-described effects can be exhibited.

Even if some of the communication holes are clogged with sludge or the like, the other communication holes discharge the refrigerant gas, and therefore, the function of discharging the refrigerant gas from the upper flexible structural groove 61 or the lower flexible structural groove 64 is not impaired, redundancy is provided, and higher reliability can be ensured.

Description of reference numerals

Sealing the container; an electric mechanism portion; a compression mechanism portion; a drive shaft; discharging a pipe; a suction tube; a stator; a rotor; a terminal; a cylinder body; rotating the plunger; an upper bearing; a bearing portion of an upper bearing; a flange portion of an upper bearing; a bearing bore of the upper bearing; a lower bearing; a bearing portion of the lower bearing; a flange portion of the lower bearing; a bearing bore of the lower bearing; a leaf; a cylinder chamber; a vane slot; a back pressure chamber; an upper discharge muffler; an upper sound-deadening chamber; a lower discharge muffler; a lower sound-deadening chamber; a main shaft portion; a secondary shaft portion; an eccentric shaft portion; a discharge port; a discharge valve; 61.. an upper flexible fabrication channel; a deepest portion of the upper flexible fabrication groove; an opening of the upper flexible fabrication channel; an upper flexible construct; 63.. a communication hole of the upper flexible construction groove; a lower flexible fabrication channel; 65.. a lower flexible construction; 66.. communicating holes of the lower flexible construction slots; a hermetic compressor; a suction muffler; a condenser; 103.. an expansion valve; an evaporator.

Claims (2)

1. A hermetic compressor including an electric mechanism part and a compression mechanism part driven by the electric mechanism part and compressing a refrigerant gas in a hermetic container,

the compression mechanism includes: a drive shaft coupled to the electric mechanism and transmitting a driving force; a cylinder block provided with a cylindrical cylinder chamber having an opening in an axial direction thereof, and configured to suck and compress a refrigerant gas; an upper bearing and a lower bearing each having a bearing hole through which the drive shaft is inserted, a bearing portion having the bearing hole and supporting the drive shaft, and a flange portion closing an opening of the cylinder chamber; a discharge port provided in at least one of the upper bearing and the lower bearing, communicating the cylinder chamber with the outside of the cylinder chamber, and discharging the refrigerant gas compressed in the cylinder chamber; a discharge muffler provided on at least one of a side of the upper bearing opposite to the cylinder and a side of the lower bearing opposite to the cylinder; a muffler chamber through which a refrigerant gas is discharged from the discharge port to the muffler chamber between the discharge muffler and the upper bearing or between the discharge muffler and the lower bearing; and a flexible structural groove provided so as to surround at least one of the opening portion on the cylinder block side of the bearing hole of the upper bearing and the opening portion on the cylinder block side of the bearing hole of the lower bearing, opening on the cylinder block side, and forming a thin-walled portion between the flexible structural groove and the bearing hole of the upper bearing or between the flexible structural groove and the bearing hole of the lower bearing,

the flexible structure groove is provided with a communication hole that communicates the flexible structure groove and the sound-deadening chamber, and the opening portion on the sound-deadening chamber side of the communication hole is provided in the vicinity of the discharge port and the connecting portion where the bearing portion and the flange portion are connected to each other, whereby the refrigerant gas that has flowed into the flexible structure groove from the cylinder chamber is discharged into the sound-deadening chamber.

2. The hermetic compressor according to claim 1,

a refrigerant having a lower density than the refrigerant of 410A or a refrigerant used at a high pressure is used.

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