JP7686501B2 - Compressors and air conditioners - Google Patents

Description

An embodiment of the present invention relates to a compressor and an air conditioner equipped with the compressor.

Refrigeration cycle devices such as air conditioners are equipped with compressors that compress refrigerants. The compressor includes, as its main elements, an electric motor that rotates a rotating shaft, a compression mechanism connected to the electric motor via the rotating shaft, and an airtight container that houses the electric motor and the compression mechanism. The electric motor includes, for example, a so-called inner rotor type motor, and includes a rotor fixed to the rotating shaft and a stator fixed to the inner circumference of the airtight container. The rotating shaft has a crank portion (eccentric portion). The compression mechanism includes, for example, a cylinder that forms a cylinder chamber, and a roller that is fitted to the eccentric portion of the rotating shaft and rotates eccentrically within the cylinder chamber. The inside of the cylinder chamber is divided by vanes into a suction chamber for the refrigerant and a compression chamber. The rotating shaft is supported by a bearing so as to be able to rotate freely. The bearing has a flange portion that defines one surface of the rotating shaft in the axial direction in the cylinder chamber, and a boss portion that extends cylindrically from the flange portion. The bearings are also fitted with a muffler to suppress pulsation and noise caused by the refrigerant compressed in the cylinder of the compression mechanism and discharged into the sealed container.

Publication number 3-30629 Japanese Utility Model Application Publication No. 2-69091 JP 2010-116787 A

The flange portion is provided with a discharge port that discharges the refrigerant compressed in the cylinder into the sealed container, and a discharge valve mechanism that controls the opening and closing of the discharge port. For this reason, the flange portion has a recess (drilled portion) near the discharge port to which the discharge valve mechanism is attached. The drilled portion is formed by digging a surface of the bearing in the axial direction of the rotating shaft, for example, the upper surface of the flange portion, to a predetermined depth. For this reason, the drilled portion is thinner than other parts of the flange portion, and the rigidity of the bearing is likely to decrease relatively. Therefore, when the rotating shaft rotates, the drilled portion may elastically deform, for example, so as to tilt the boss portion relative to the flange portion. Depending on the degree of deformation of the drilled portion, the support rigidity of the rotating shaft by the bearing may decrease, and the rotating shaft may bend and vibrate, increasing noise.

A compressor according to one embodiment includes a cylinder, a rotating shaft, a bearing, a discharge valve mechanism, and a muffler. The cylinder compresses a refrigerant. The rotating shaft has an eccentric portion disposed in the cylinder. The bearing has a flange portion that defines one surface of the rotating shaft in the axial direction of the cylinder, and a boss portion that is continuous with the flange portion and extends in a cylindrical shape concentric with the rotating shaft to rotatably support the rotating shaft. The discharge valve mechanism is disposed in the flange portion and has a discharge valve that deforms and opens when the refrigerant compressed in the cylinder reaches a predetermined discharge pressure, and is elongated in a predetermined direction, and a valve stopper that suppresses further deformation when the discharge valve opens. The muffler covers the bearing so as to surround the area between the flange portion and the boss portion, and forms a muffler chamber between the flange portion and the boss portion from which the refrigerant compressed in the cylinder is discharged. The muffler defines the outer contour of the muffler chamber by an end face portion, which is a face portion on one end side in the axial direction of the rotating shaft, a flange portion, which is a face portion on the other end side in the axial direction of the rotating shaft, and a side portion that connects the end face portion and the flange portion in a cylindrical shape around the entire circumference of the rotating shaft in the circumferential direction, and has a recess in which the end face portion and the side portion are recessed into the inside of the muffler chamber. The flange portion has an end face on one end side in the axial direction of the rotating shaft recessed, and has a dug portion in which the discharge valve and the valve guard are assembled. The recess is arranged so that when the recess is projected onto the flange portion from the axial direction of the rotating shaft, it intersects with the longitudinal direction of the discharge valve and overlaps with the dug portion. The recess is composed of a first surface portion, a second surface portion, a third surface portion, and a fourth surface portion. The first surface portion and the second surface portion are parallel to a predetermined imaginary plane that includes the axis of the rotating shaft and intersects with the longitudinal direction of the discharge valve. The third surface portion and the fourth surface portion are continuous with each other, and the third surface portion connects between the first surface portion and the second surface portion on one side of the axis of the rotating shaft, and the fourth surface portion connects between the first surface portion and the second surface portion on the other side of the axis of the rotating shaft. The third surface portion has a through hole through which a first fastener that fixes the muffler to the boss portion is inserted. The first surface portion and the second surface portion face each other at a distance that does not interfere with the first fastener.

1 is a circuit diagram illustrating a schematic configuration of an air conditioner according to an embodiment. FIG. 2 is a vertical sectional view of the compressor according to the embodiment. FIG. 2 is a schematic top view of a bearing having a discharge valve mechanism (a first bearing having a first discharge valve mechanism) of the compressor according to the embodiment. 4 is a diagram illustrating a cross section of a bearing (first bearing) taken along an arrow A3 portion illustrated in FIG. 3 . FIG. FIG. 2 is a schematic top view of a state in which a muffler (first muffler) of the compressor according to the embodiment is assembled to a bearing (first bearing). FIG. 2 is a perspective view illustrating a schematic configuration of a muffler (first muffler) of the compressor according to the embodiment.

One embodiment will be described below with reference to Figures 1 to 6.

Figure 1 is a refrigeration cycle circuit diagram of an air conditioner 1 according to this embodiment. The air conditioner 1 is a device that performs air conditioning using this refrigeration cycle, and is an example of a refrigeration cycle device. The main elements of the air conditioner 1 include a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, an outdoor blower 40, an expansion device 5, an indoor heat exchanger 6, and an indoor blower 60.

As shown in FIG. 1, the discharge side of the compressor 2 is connected to a first port 3a of the four-way valve 3. The second port 3b of the four-way valve 3 is connected to an outdoor heat exchanger 4. The outdoor heat exchanger 4 is connected to an indoor heat exchanger 6 via an expansion device 5. The indoor heat exchanger 6 is connected to a third port 3c of the four-way valve 3. The fourth port 3d of the four-way valve 3 is connected to the suction side of the compressor 2 via an accumulator 8.

The refrigerant circulates through a circulation circuit 7 that runs from the discharge side of the compressor 2 through an outdoor heat exchanger 4, an expansion device 5, an indoor heat exchanger 6, and an accumulator 8 to the suction side. The refrigerant is preferably a chlorine-free refrigerant, and examples of applicable refrigerants include R448A, R449A, R449B, R407G, R407H, R449C, R456A, R516A, R406B, R463A, R744, and HC-based refrigerants.

For example, when the air conditioner 1 operates in cooling mode, the four-way valve 3 switches so that the first port 3a communicates with the second port 3b and the third port 3c communicates with the fourth port 3d. When the air conditioner 1 starts operating in cooling mode, high-temperature, high-pressure gas-phase refrigerant compressed by the compressor 2 is discharged into the circulation circuit 7. The discharged gas-phase refrigerant is guided via the four-way valve 3 to the outdoor heat exchanger 4, which functions as a condenser (heat radiator).

The gas-phase refrigerant guided to the outdoor heat exchanger 4 condenses through heat exchange with the air (outdoor air) drawn in by the outdoor blower 40, and changes to a high-pressure liquid-phase refrigerant. The high-pressure liquid-phase refrigerant is reduced in pressure as it passes through the expansion device 5, and changes to a low-pressure two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant is guided to the indoor heat exchanger 6, which functions as an evaporator (heat absorber), and exchanges heat with the air (indoor air) drawn in by the indoor blower 60 as it passes through the indoor heat exchanger 6.

As a result, the gas-liquid two-phase refrigerant absorbs heat from the air and evaporates, changing into a low-temperature, low-pressure gas-phase refrigerant. The air passing through the indoor heat exchanger 6 is cooled by the latent heat of evaporation of the liquid-phase refrigerant, and is sent as cold air by the indoor blower 60 to the area to be conditioned (cooled).

The low-temperature, low-pressure gas-phase refrigerant that has passed through the indoor heat exchanger 6 is guided to the accumulator 8 via the four-way valve 3. If the refrigerant contains liquid-phase refrigerant that has not completely evaporated, it is separated into liquid-phase refrigerant and gas-phase refrigerant here. The low-temperature, low-pressure gas-phase refrigerant separated from the liquid-phase refrigerant is sucked from the accumulator 8 into the compressor 2, where it is compressed again into high-temperature, high-pressure gas-phase refrigerant and discharged into the circulation circuit 7.

On the other hand, when the air conditioner 1 operates in heating mode, the four-way valve 3 switches so that the first port 3a communicates with the third port 3c and the second port 3b communicates with the fourth port 3d. When the air conditioner 1 starts operating in heating mode, the high-temperature, high-pressure gas-phase refrigerant discharged from the compressor 2 is guided via the four-way valve 3 to the indoor heat exchanger 6, where it exchanges heat with the air passing through the indoor heat exchanger 6. In this case, the indoor heat exchanger 6 functions as a condenser.

As a result, the gas-phase refrigerant passing through the indoor heat exchanger 6 condenses through heat exchange with the air (indoor air) drawn in by the indoor blower 60, and changes into a high-pressure liquid-phase refrigerant. The air passing through the indoor heat exchanger 6 is heated through heat exchange with the gas-phase refrigerant, and is sent as warm air by the indoor blower 60 to the area to be air-conditioned (heated).

The high-temperature liquid-phase refrigerant that has passed through the indoor heat exchanger 6 is guided to the expansion device 5, where it is decompressed and converted into a low-pressure two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant is guided to the outdoor heat exchanger 4, which functions as an evaporator, and evaporates by exchanging heat with the air (outdoor air) drawn in by the outdoor blower 40, converting into a low-temperature, low-pressure gas-phase refrigerant. The low-temperature, low-pressure gas-phase refrigerant that has passed through the outdoor heat exchanger 4 is drawn into the compressor 2 via the four-way valve 3 and accumulator 8, where it is compressed again into a high-temperature, high-pressure gas-phase refrigerant and discharged into the circulation circuit 7.

In this embodiment, the air conditioner 1 can be operated in either cooling mode or heating mode, but the air conditioner 1 may also be, for example, a dedicated cooling or heating machine that can be operated only in either cooling mode or heating mode.

Next, the specific configuration of the compressor 2 used in the air conditioner 1 will be described with reference to FIG. 2. FIG. 2 is a vertical cross-sectional view of the compressor 2. As shown in FIG. 2, the compressor 2 is a so-called vertical rotary compressor, and includes a sealed container 10, a compression mechanism 11, and an electric motor 12 as its main elements. In the following description, the side where the compression mechanism 11 is located is referred to as the bottom, and the side where the electric motor 12 is located is referred to as the top, based on the relative positional relationship between the compression mechanism 11 and the electric motor 12 aligned along the central axis O1 of the sealed container 10 described below.

The sealed container 10 has a cylindrical peripheral wall 10a and stands vertically relative to the installation surface. The installation surface may be, for example, the bottom plate of an outdoor unit. A discharge pipe 10b is provided at the upper end of the sealed container 10. The discharge pipe 10b is connected to the first port 3a of the four-way valve 3 via the circulation circuit 7. An oil reservoir 10c that stores lubricating oil is provided at the bottom of the sealed container 10.

The compression mechanism 11 is housed in the lower part of the sealed container 10 so as to be immersed in the lubricating oil. In the example shown in FIG. 2, the compression mechanism 11 has a twin-cylinder structure, and includes a first cylinder 13, a second cylinder 14, and a rotating shaft 15 as main elements. The first cylinder 13 and the second cylinder 14 each have a roller (rolling piston) and a vane inside. The number of cylinders in the compression mechanism is not limited to two, and may be one or three or more.

The first cylinder 13 is fixed to the inner surface of the peripheral wall 10a of the sealed container 10. The second cylinder 14 is fixed to the lower surface of the first cylinder 13 via a partition plate 18.

A first bearing 20 is fixed above the first cylinder 13. The first bearing 20 covers the inner diameter of the first cylinder 13 from above and protrudes toward the upper side of the first cylinder 13. The space surrounded by the inner diameter of the first cylinder 13, the partition plate 18, and the first bearing 20 constitutes the first cylinder chamber. The partition plate 18 corresponds to a closing member that defines the lower surface of the first cylinder chamber, and the first bearing 20 corresponds to a closing member that defines the upper surface of the first cylinder chamber.

A second bearing 22 is fixed below the second cylinder 14. The second bearing 22 covers the inner diameter of the second cylinder 14 from below and protrudes downward from the second cylinder 14. The space surrounded by the inner diameter of the second cylinder 14, the partition plate 18, and the second bearing 22 constitutes a second cylinder chamber. The partition plate 18 corresponds to a closing member that defines the upper surface of the second cylinder chamber, and the second bearing 22 corresponds to a closing member that defines the lower surface of the second cylinder chamber. The first cylinder chamber and the second cylinder chamber are arranged concentrically with the central axis O1 of the sealed container 10.

The first cylinder chamber and the second cylinder chamber are connected to the accumulator 8 via a suction pipe (not shown), which is part of the circulation circuit 7. The gas phase refrigerant separated from the liquid phase refrigerant in the accumulator 8 is guided to the first cylinder chamber and the second cylinder chamber through the suction pipe.

The rotating shaft 15 has an axis that is coaxial with the central axis O1 of the sealed container 10, and penetrates the first cylinder chamber, the second cylinder chamber, and the partition plate 18. The rotating shaft 15 has a first journal portion 27a, a second journal portion 27b, and a pair of crank pin portions (eccentric portions) 28a, 28b. In other words, the rotating shaft 15 is configured as a crankshaft. The first journal portion 27a is rotatably supported by the first bearing 20. The second journal portion 27b is rotatably supported by the second bearing 22.

The rotating shaft 15 further has an extension 27c that extends coaxially from the first journal portion 27a. The extension 27c passes through the first bearing 20 and protrudes above the compression mechanism 11. A rotor 33 of the electric motor 12, which will be described later, is fixed to the extension 27c.

The eccentric portions 28a, 28b are located between the first journal portion 27a and the second journal portion 27b. The eccentric portions 28a, 28b have a phase difference of, for example, 180 degrees, and have the same amount of eccentricity with respect to the central axis O1 of the sealed container 10. One eccentric portion (hereinafter referred to as the first eccentric portion) 28a is housed in the first cylinder chamber. The other eccentric portion (hereinafter referred to as the second eccentric portion) 28b is housed in the second cylinder chamber.

The rollers 16 and 17 are fitted to the outer peripheral surfaces of the first eccentric portion 28a and the second eccentric portion 28b, respectively. A small gap is provided between the inner peripheral surface of the rollers 16 and 17 and the outer peripheral surface of the eccentric portions 28a and 28b to allow the rollers 16 and 17 to rotate relative to the eccentric portions 28a and 28b. As a result, when the rotating shaft 15 rotates, the rollers 16 and 17 rotate eccentrically within the cylinder chamber, and a part of the outer peripheral surface of the rollers 16 and 17 comes into contact with the inner peripheral surface of the cylinder chamber via an oil film.

Vanes (not shown) are arranged in the first cylinder 13 and the second cylinder 14. The vanes are supported by the cylinders 13 and 14 while being biased radially inward by a biasing means. The tip of each vane is slidably pressed against the outer circumferential surface of the rollers 16 and 17. These vanes cooperate with the rollers 16 and 17 to divide the cylinder chambers of the cylinders 13 and 14 into a suction chamber and a compression chamber, respectively, and move (advance and retreat) in a direction protruding into the cylinder chamber or retracting from the cylinder chamber in accordance with the eccentric rotation of the rollers 16 and 17. As the vanes advance and retreat relative to the cylinder chamber in this way, the volumes of the suction chamber and compression chamber of the cylinder chamber change, and the gas-phase refrigerant sucked into the cylinder chamber from the above-mentioned suction pipe is compressed.

The high-temperature, high-pressure gas-phase refrigerant compressed in each cylinder chamber of the first cylinder 13 and the second cylinder 14 is discharged into the sealed container 10 via the discharge valve mechanisms 21, 23 described below. The discharged gas-phase refrigerant rises inside the sealed container 10. Furthermore, while the compression mechanism 11 is in operation, the lubricating oil stored in the oil reservoir 10c of the sealed container 10 is agitated. The agitated lubricating oil becomes mist-like and rises inside the sealed container 10 toward the discharge pipe 10b along with the flow of the gas-phase refrigerant. The sealed container 10 is equipped with an oil separator and other devices that separate the lubricating oil contained in the gas-phase refrigerant rising inside.

The electric motor unit 12 is housed in the middle of the sealed container 10 along the central axis O1 so as to be located between the compression mechanism unit 11 and the discharge pipe 10b. The electric motor unit 12 includes a so-called inner rotor type motor, and is equipped with a rotor 33 fixed to the rotating shaft 15, and a stator 34 fixed to the inner peripheral surface of the peripheral wall 10a of the sealed container 10. When a voltage is applied from a power source to the electric motor unit 12, the rotor 33 rotates about the central axis O1 relative to the stator 34, and the rotating shaft 15 rotates together with the rotor 33. The rotating shaft 15 is rotatably supported by two bearings 20, 22.

Of the two bearings 20, 22, one is a main bearing (hereinafter referred to as the first bearing) 20, and the other is a sub-bearing (hereinafter referred to as the second bearing) 22. The first bearing 20 and the second bearing 22 each rotatably support the rotating shaft 15. The first bearing 20 defines the upper surface of the first cylinder chamber in the first cylinder 13, and the second bearing 22 defines the lower surface of the second cylinder chamber in the second cylinder 14. The upper surface is the end surface of one end of the cylinders 13, 14 in the axial direction of the rotating shaft 15 (the direction along the central axis O1 of the sealed container 10), and the lower surface is the end surface of the other end of the cylinders 13, 14 in that direction. In other words, the first bearing 20 corresponds to a member that closes the first cylinder chamber from above, and the second bearing 22 corresponds to a member that closes the second cylinder chamber from below.

The first bearing 20 has a first flange portion 20a that defines the upper surface of the first cylinder chamber in the first cylinder 13, and a first boss portion 20b that extends upward in a cylindrical shape continuous with the first flange portion 20a.

The first flange portion 20a is located at the lower end of the first boss portion 20b, extends radially outward from the first boss portion 20b, and continues around the entire circumference in a circular shape concentric with the axis of the rotating shaft 15. The first flange portion 20a is formed with a discharge hole (hereinafter referred to as the first discharge hole) 20c (see FIG. 3) that discharges the refrigerant from the compression chamber of the first cylinder 13. The first discharge hole 20c penetrates a part of the first flange portion 20a from top to bottom and communicates with the inside of the compression chamber of the first cylinder 13. The first discharge hole 20c is opened and closed by a predetermined valve mechanism (hereinafter referred to as the first discharge valve mechanism) 21. The first discharge valve mechanism 21 is disposed in the first flange portion 20a, and opens the first discharge hole 20c as the pressure in the compression chamber of the first cylinder 13 rises, discharging the high-temperature, high-pressure gas-phase refrigerant from the compression chamber.

The first boss portion 20b is a portion of the first bearing 20 through which the rotating shaft 15, specifically the first journal portion 27a, is inserted and rotatably supported. The first boss portion 20b is arranged concentrically with the rotating shaft 15. In other words, the first boss portion 20b is arranged perpendicular to the first flange portion 20a. When the first journal portion 27a is inserted into the first boss portion 20b, the outer peripheral surface of the first journal portion 27a slides against the inner peripheral surface of the first boss portion 20b.

The second bearing 22 has a second flange portion 22a that defines the lower surface of the second cylinder chamber in the second cylinder 14, and a second boss portion 22b that extends downward in a cylindrical shape continuous with the second flange portion 22a.

The second flange portion 22a is located at the upper end of the second boss portion 22b, extends radially outward from the second boss portion 22b, and continues around the entire circumference in a circular shape concentric with the axis of the rotating shaft 15. The second flange portion 22a has a discharge hole (not shown; hereinafter referred to as the second discharge hole) that discharges the refrigerant from the compression chamber of the second cylinder 14. The second discharge hole penetrates a part of the second flange portion 22a from top to bottom and communicates with the compression chamber of the second cylinder 14. The second discharge hole is opened and closed by a predetermined valve mechanism (hereinafter referred to as the second discharge valve mechanism) 23. The second discharge valve mechanism 23 opens the second discharge hole as the pressure in the compression chamber of the second cylinder 14 rises, discharging the high-temperature, high-pressure gas-phase refrigerant from the compression chamber.

The second boss portion 22b is a portion of the second bearing 22 through which the rotating shaft 15, specifically the second journal portion 27b, is inserted and rotatably supported. The second boss portion 22b is arranged concentrically with the rotating shaft 15. In other words, the second boss portion 22b is arranged perpendicular to the second flange portion 22a. When the second journal portion 27b is inserted into the second boss portion 22b, the outer peripheral surface of the second journal portion 27b slides against the inner peripheral surface of the second boss portion 22b.

Figures 3 and 4 show the configuration of the first discharge valve mechanism 21. Figure 3 is a schematic view of the first bearing 20 having the first discharge valve mechanism 21 from above. Figure 4 is a schematic cross-sectional view of the first bearing 20 at the portion indicated by arrow A3 in Figure 3. The configurations of the first discharge valve mechanism 21 and the second discharge valve mechanism 23 are almost the same, except for the difference that arises from the fact that they are positioned upside down. Therefore, the configuration of the second discharge valve mechanism 23 is similar to the configuration shown in Figures 3 and 4. For this reason, an example configuration of the first discharge valve mechanism 21 will be described below.

As shown in Figures 3 and 4, the first discharge valve mechanism 21 is provided on the first flange portion 20a of the first bearing 20, and appropriately opens the first discharge hole 20c to discharge the refrigerant compressed in the compression chamber of the first cylinder 13 from the compression chamber. The first discharge valve mechanism 21 includes a discharge valve 21a and a valve holder 21b. The discharge valve 21a and the valve holder 21b are fixed to the first flange portion 20a by a predetermined fastener 21c. As the fastener 21c, any fastener such as a bolt, a screw, or a rivet can be used.

The first discharge hole 20c opens to the bottom of a recess (hereinafter referred to as a recessed portion) 20d formed in the first flange portion 20a. The recessed portion 20d is formed by recessing the upper surface (end surface on one end side in the axial direction of the rotating shaft 15) 20e of the first flange portion 20a to a predetermined depth. The depth of the recessed portion 20d is approximately equal to the vertical dimension of the first discharge valve mechanism 21 (overlapping discharge valve 21a and valve holder 21b). The contour of the recessed portion 20d as viewed from above the first flange portion 20a is slightly larger than the contour of the first discharge valve mechanism 21 as viewed from above, so that the first discharge valve mechanism 21 (discharge valve 21a and valve holder 21b) can be assembled. That is, the longitudinal direction of the recessed portion 20d is parallel to the longitudinal direction of the discharge valve 21a and the valve guard 21b described later. By forming the recessed portion 20d in this manner, when the first discharge valve mechanism 21 is assembled to the recessed portion 20d, the first discharge valve mechanism 21 is recessed into the recessed portion 20d. In other words, the recessed portion 20d is formed in the first flange portion 20a as a recess for assembling the first discharge valve mechanism 21. Note that the second flange portion 22a of the second bearing 22 has a recessed portion 22d (see FIG. 2) similar to the recessed portion 20d formed as a recess for assembling the second discharge valve mechanism 23.

The discharge valve 21a is a member for closing or opening the first discharge hole 20c, and is in the form of a plate elongated in a predetermined direction. The discharge valve 21a is formed in a strip shape from an elastically deformable material such as spring steel. As a result, the discharge valve 21a has a cantilevered leaf spring structure in which one end in the longitudinal direction fixed by the fixing device 21c is the fixed end and the other end in the longitudinal direction is the free end, and is capable of bending and deforming. Specifically, the discharge valve 21a deforms when the high-temperature, high-pressure gas-phase refrigerant compressed in the compression chamber of the first cylinder 13 reaches a predetermined discharge pressure, and opens the first discharge hole 20c. Hereinafter, this state of the discharge valve 21a is referred to as a deformed state. In a state before the first discharge hole 20c is opened (hereinafter referred to as a normal state), the discharge valve 21a is pressed against the periphery of the first discharge hole 20c so as to close the first discharge hole 20c with an elastic force (pressing force) smaller than the predetermined discharge pressure. Therefore, when the refrigerant exceeds the atmospheric pressure in the first muffler 41 and reaches a predetermined discharge pressure, the discharge valve 21a deforms against the elastic force (pressure) to open the first discharge hole 20c and discharge the refrigerant. When the first discharge hole 20c is opened to discharge the refrigerant and the discharge pressure of the refrigerant falls below the predetermined pressure, the discharge valve 21a elastically recovers from the deformed state to its normal state and closes the first discharge hole 20c again.

The valve holder 21b is a member for restricting the deformation of the discharge valve 21a, and is a plate-like member that is long in a predetermined direction and thicker than the discharge valve 21a. The valve holder 21b is formed of, for example, steel material. The valve holder 21b is arranged with its longitudinal direction aligned with the longitudinal direction of the discharge valve 21a. These longitudinal directions are directions that intersect with the radial direction of the first flange portion 20a, in other words, directions that intersect with the plane including the axis of the rotating shaft 15. In addition, these longitudinal directions are parallel to the longitudinal direction of the recessed portion 20d. In the example shown in FIG. 3, such longitudinal direction is a direction perpendicular to the radial direction of the first flange portion 20a, in other words, a direction perpendicular to the plane including the axis of the rotating shaft 15. The valve holder 21b is arranged to face the discharge valve 21a in the process of the discharge valve 21a being displaced to a position away from the first discharge hole 20c when the first discharge hole 20c is opened. In the example shown in Figures 3 and 4, the valve holder 21b is disposed above the discharge valve 21a so as to cover the discharge valve 21a. The valve holder 21b is curved to fit the discharge valve 21a in a bent (floated) state, i.e., in a deformed state, so as to open the first discharge hole 20c. As a result, when the discharge valve 21a is bent and deformed to open the first discharge hole 20c, i.e., in a deformed state, the valve holder 21b comes into contact with the deformed discharge valve 21a and suppresses further deformation (floating) of the discharge valve 21a.

Above the first bearing 20, a muffler (hereinafter referred to as the first muffler) 41 that covers the first bearing 20 is provided. The first muffler 41 suppresses pulsation and noise caused by the refrigerant discharged from the compression chamber of the first cylinder 13 into the sealed container 10, for example. The first muffler 41 covers the first bearing 20 so as to surround the area between the first flange portion 20a and the first boss portion 20b, and forms a first muffler chamber 43 between the first flange portion 20a and the first boss portion 20b. The first muffler chamber 43 is a space where the high-temperature, high-pressure refrigerant compressed in the compression chamber of the first cylinder 13 is first discharged from the first discharge hole 20c. The first muffler 41 has a communication hole 41a that communicates the inside and outside (up and down) of the first muffler 41. The high-temperature, high-pressure gas phase refrigerant discharged through the first discharge hole 20c into the first muffler chamber 43 is discharged into the sealed container 10 through the communication hole 41a.

As shown in FIG. 2, a muffler (hereinafter referred to as the second muffler) 42 that covers the second bearing 22 is provided below the second bearing 22. The second muffler 42 suppresses pulsation and noise caused by the refrigerant discharged from the compression chamber of the second cylinder 14 into the sealed container 10, for example. The second muffler 42 covers the second bearing 22 so as to surround the area between the second flange portion 22a and the second boss portion 22b, and forms a second muffler chamber 44 between the second flange portion 22a and the second boss portion 22b. The second muffler chamber 44 is a space where the high-temperature, high-pressure refrigerant compressed in the compression chamber of the second cylinder 14 is first discharged from the second discharge hole. The second muffler chamber 44 is connected to the first muffler chamber 43 through a through hole provided in the compression mechanism portion 11. The through hole penetrates the second flange portion 22a, the second cylinder 14, the partition plate 18, the first cylinder 13, and the first flange portion 20a, respectively, and opens into the second muffler chamber 44 and the first muffler chamber 43. The high-temperature, high-pressure gas-phase refrigerant discharged into the second muffler chamber 44 through the second discharge hole reaches the first muffler chamber 43 through the through hole, and is then discharged into the sealed container 10 through the communication hole 41a.

Figures 5 and 6 show the configuration of the first muffler 41 according to this embodiment. Figure 5 is a schematic view from above of the first muffler 41 assembled to the first bearing 20. Figure 6 is a schematic perspective view of the first muffler 41.

4 to 6, the first muffler 41 is a three-dimensional element having three parts, an end surface portion 45, a side surface portion 46, and a flange portion 47, and these three parts are configured to be thin-walled. The end surface portion 45, the side surface portion 46, and the flange portion 47 define the outer shape of the first muffler chamber 43. The end surface portion 45 is a surface portion on one end side of the first muffler 41 in the axial direction of the rotating shaft 15 (the direction along the central axis O1 of the sealed container 10), and is a surface portion that spreads radially with respect to the axial center of the rotating shaft 15. In the example shown in FIG. 5 and FIG. 6, the end surface portion 45 corresponds to the upper surface portion of the first muffler 41. The end surface portion 45 is annular with a circular opening 45a through which the first boss portion 20b of the first bearing 20 is inserted. The center of the opening 45a is located on the axial center of the rotating shaft 15 (the central axis O1 of the sealed container 10). In other words, the first muffler 41 is arranged so that the opening 45a is concentric with the rotating shaft 15. The diameter (diameter) of the opening 45a is approximately equal to the outer diameter of the insertion portion of the first boss portion 20b.

The end surface portion 45 has five pieces 45b to 45f that extend radially from the center of the opening 45a. The five pieces 45b to 45f are arranged at approximately equal intervals in the circumferential direction of the opening 45a. The five pieces 45b to 45f are smoothly continuous with each other, except for the area between pieces 45b and 45f, so that adjacent pieces gradually approach the center line of the opening 45a (the central axis O1 of the sealed container 10). Of these, four pieces 45b to 45e each have a communication hole 41a. The number of pieces that the end surface portion has is not limited to five, and may be four or less or six or more.

The side portion 46 connects the end surface portion 45 (specifically, the five pieces 45b-45f) and the flange portion 47 in a cylindrical shape around the opening 45a, in other words, the entire circumferential direction of the axis of the rotating shaft 15. In other words, the side portion 46 corresponds to the outer periphery of the first muffler 41. The side portion 46 is cylindrical in shape, with the side connected to the end surface portion 45 being thinner than the side connected to the flange portion 47. In other words, the side portion 46 is inclined so that it approaches the center line of the opening 45a (the central axis O1 of the sealed container 10) as it moves from the side connected to the flange portion 47 toward the side connected to the end surface portion 45.

The flange portion 47 is a surface portion on the other end side of the first muffler 41 in the axial direction of the rotating shaft 15 (the direction along the central axis O1 of the sealed container 10), and is a surface portion that extends in a circular shape concentric with the axis of the rotating shaft 15 and is approximately parallel to the end surface portion 45. In the example shown in Figures 5 and 6, the flange portion 47 corresponds to the lower surface portion of the first muffler 41 and is continuous with the side surface portion 46 at the lower end side of the first muffler 41. The flange portion 47 has a through hole through which a bolt is inserted. The bolt is an example of a fastener (in this embodiment, a second fastener for fastening the first muffler 41) for fastening the first muffler 41 to the first flange portion 20a. In the example shown in Figures 5 and 6, the flange portion 47 has five through holes 47a to 47e. A total of five bolts 48a to 48e are inserted into each of the through holes 47a to 47e. The through holes 47a to 47e are arranged in a line at approximately equal intervals in the circumferential direction of the opening 45a. When viewed from the axial direction of the rotating shaft 15, the five through holes 47a to 47e are arranged so that they are positioned one by one between the adjacent pieces 45b to 45f on the end surface portion 45. In other words, the five through holes 47a to 47e and the five pieces 45b to 45f are arranged so that they are alternately positioned with approximately the same phase difference in the circumferential direction of the opening 45a. The number of through holes in the flange portion is not limited to five, and may be four or less, or six or more. For example, the number of through holes in the flange portion may be the same as the number of pieces in the end surface portion.

The through holes 47a to 47e are each connected to one of the through holes 20f to 20j formed in the first flange portion 20a of the first bearing 20. In the example shown in Figures 3 to 6, the first through hole 47a is connected to the first through hole 20f. A bolt 48a is inserted into these connected through holes 47a and 20f. Similarly, the second through hole 47b is connected to the second through hole 20g. A bolt 48b is inserted into these connected through holes 47b and 20g. The third through hole 47c is connected to the third through hole 20h. A bolt 48c is inserted into these connected through holes 47c and 20h. The fourth through hole 47d is connected to the fourth through hole 20i. A bolt 48d is inserted through these communicating through holes 47d, 20i. The fifth through hole 47e is connected to the fifth through hole 20j. A bolt 48e is inserted through these communicating through holes 47e, 20j. These bolts 48a to 48e are each fastened to the first cylinder 13. As a result, the first muffler 41 and the first bearing 20 are assembled to the first cylinder 13. In other words, the flange portion 47 is fixed to the first cylinder 13 via the first flange portion 20a of the first bearing 20 by the bolts 48a to 48e. That is, the bolts 48a to 48e fix the flange portion 47 to the first cylinder 13 via the first flange portion 20a.

The first muffler 41 has a recess 49 formed by recessing a portion that defines the outer contour of the first muffler chamber 43 into the first muffler chamber 43. The configuration of the recess 49 will be described below with reference to Figures 4 to 6.

The recess 49 is formed by recessing the end surface portion 45 and the side surface portion 46 into the first muffler chamber 43. When viewed from the first muffler chamber 43, the recess 49 is a protrusion that protrudes into the first muffler chamber 43 and corresponds to a rib of the first muffler 41. In other words, the recess 49 functions as a reinforcing portion that suppresses deformation of the first muffler 41. In the example shown in Figures 4 to 6, the recess 49 is formed by recessing the portion between the piece portion 45b and the piece portion 45f on the end surface portion 45, and the portion connecting the portion between the piece portion 45b and the piece portion 45f on the side surface portion 46 and the flange portion 47 into the first muffler chamber 43.

When the recess 49 is projected onto the upper surface 20e of the first flange portion 20a from the axial direction of the rotating shaft 15, the recess 49 is positioned so as to intersect with the longitudinal direction of the recessed portion 20d and overlap with the recessed portion 20d. In other words, the recess 49 is positioned near the recessed portion 20d, in other words, the discharge valve 21a and the valve holder 21b.

The recess 49 is configured to include four surfaces 49a to 49d as main surfaces. The first surface 49a and the second surface 49b face each other in a pair approximately parallel to the circumferential direction of the opening 45a. The first surface 49a and the second surface 49b are parallel to a predetermined plane (imaginary plane) that includes the axis of the rotating shaft 15 and intersects with the longitudinal direction of the discharge valve 21a. In this embodiment, as an example, the first surface 49a and the second surface 49b are parallel to a plane that includes the axis of the rotating shaft 15 and is perpendicular to the longitudinal direction of the discharge valve 21a. To put it another way, when the recess 49 is projected onto the upper surface 20e of the first flange portion 20a from the axial direction of the rotating shaft 15, the first surface portion 49a and the second surface portion 49b intersect with the longitudinal direction of the recessed portion 20d, and are arranged so as to overlap the recessed portion 20d, in other words the discharge valve 21a and the valve holder 21b, perpendicular to the longitudinal direction of the recessed portion 20d.

The third surface portion 49c and the fourth surface portion 49d are continuous with each other and are surfaces that connect the first surface portion 49a and the second surface portion 49b. The first surface portion 49a and the second surface portion 49b are continuous through the third surface portion 49c and the fourth surface portion 49d. The third surface portion 49c stands almost parallel to the center line of the opening 45a (the central axis O1 of the sealed container 10) and connects the first surface portion 49a and the second surface portion 49b at the top. The fourth surface portion 49d stands at an angle with respect to the center line of the opening 45a (the central axis O1 of the sealed container 10) and connects the first surface portion 49a and the second surface portion 49b at the bottom. The fourth surface 49d is inclined so that it approaches the center line of the opening 45a (the central axis O1 of the sealed container 10) as it approaches the side where it continues with the third surface 49c (here, the upper side). The third surface 49c and the fourth surface 49d are perpendicular to and continuous with the first surface 49a and the second surface 49b.

The third surface portion 49c has a through hole 49e through which the bolt 50 is inserted. The bolt 50 is an example of a fastener (in this embodiment, a first fastener for fastening the first muffler 41) for fastening the first muffler 41, specifically the side portion 46, to the first boss portion 20b. As shown in FIG. 5, the first boss portion 20b is provided with a seat portion 20k having a flat seat surface that can abut against the third surface portion 49c. The bolt 50 is fastened to a bolt hole 20l formed in the seat portion 20k. The first surface portion 49a and the second surface portion 49b face each other at a distance that does not interfere with the head portion 50a of the bolt 50.

In this way, the first muffler 41 is fixed to the first cylinder 13 via the first flange portion 20a by the bolts 48a to 48e with respect to the first bearing 20, and is fixed to the first boss portion 20b by the bolt 50. The first flange portion 20a is arranged to extend radially outward of the rotating shaft 15, and the first boss portion 20b is arranged concentrically with the rotating shaft 15. In other words, the first flange portion 20a and the first boss portion 20b are arranged so as to be perpendicular to each other. Therefore, the first muffler 41 can be firmly fixed to the first bearing 20 from two directions, the radial direction and the axial direction of the rotating shaft 15. This can increase the rigidity of the first muffler 41 against the inclination of the first boss portion 20b when the rotating shaft 15 rotates, for example.

The first muffler 41 also has a recess 49 disposed near the recessed portion 20d of the first flange portion 20a. As described above, the recess 49 functions as a reinforcing portion that suppresses deformation of the first muffler 41. Therefore, when the rotating shaft 15 rotates, the recess 49 can bear the force that elastically deforms the recessed portion 20d so as to tilt the first boss portion 20b relative to the first flange portion 20a. This suppresses elastic deformation of the recessed portion 20d, and suppresses deformation such as tilting the first boss portion 20b relative to the first flange portion 20a. As a result, it is possible to reduce noise caused by bending vibration of the rotating shaft 15, for example.

The second muffler 42 does not have a portion corresponding to the recess 49 of the first muffler 41 described above. This is for the following reason. As shown in FIG. 2, the second boss portion 22b of the second bearing 22 is shorter in the axial direction of the rotating shaft 15 than the first boss portion 20b of the first bearing 20. That is, the second boss portion 22b is less likely to deform so as to tilt with respect to the second flange portion 22a, and even if it does deform, it is not as deformed as the first boss portion 20b. Therefore, in this embodiment, the second muffler 42 is configured to omit a portion corresponding to the recess 49. That is, the second muffler 42 can be configured in the same way as the first muffler 41, except for the fact that it does not have a portion corresponding to the recess 49 and the difference associated with being upside down (top and bottom). However, the second muffler 42 may have a recess similar to that of the first muffler 41.

Although each embodiment of the present invention has been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims.

1...air conditioner, 2...compressor, 3...four-way valve, 4...outdoor heat exchanger, 5...expansion device, 6...indoor heat exchanger, 7...circulation circuit, 8...accumulator, 10...sealed container, 11...compression mechanism section, 12...motor section, 13...first cylinder, 14...second cylinder, 15...rotating shaft, 18...partition plate, 20...first bearing, 20a...first flange section, 20b...first boss section, 20c...first discharge hole, 20d...recess (dug section), 20e...upper surface, 20f-20j...through holes, 20k...seat section, 20l...bolt hole, 21...first discharge valve mechanism, 21a...discharge valve, 21b...valve retainer, 21c...fixing device, 22...second bearing, 22a...second flange portion, 22b...second boss portion, 23...second discharge valve mechanism, 41...first muffler, 41a...communication hole, 42...second muffler, 43...first muffler chamber, 44...second muffler chamber, 45...end surface portion, 45a...opening, 45b-45f...strip portion, 46...side portion, 47...flange portion, 47a-47e...through hole, 48a-48e...bolt, 49...recess, 49a...first surface portion, 49b...second surface portion, 49c...third surface portion, 49d...fourth surface portion, 49e...through hole, 50...bolt, 50a...head portion, O1...central axis of sealed container.

Claims (3)

A cylinder for compressing a refrigerant;
A rotating shaft having an eccentric portion disposed in the cylinder;
a bearing including a flange portion defining one surface of the cylinder in an axial direction of the rotating shaft, and a boss portion extending contiguous with the flange portion into a cylindrical shape concentric with the rotating shaft and supporting the rotating shaft so as to be freely rotatable;
a discharge valve mechanism disposed on the flange portion, the discharge valve mechanism having a discharge valve elongated in a predetermined direction and deforming and opening when the refrigerant compressed in the cylinder reaches a predetermined discharge pressure, and a valve stopper that suppresses further deformation of the discharge valve when the discharge valve opens;
a muffler that covers the bearing so as to surround the area between the flange portion and the boss portion and forms a muffler chamber between the flange portion and the boss portion, into which the refrigerant compressed in the cylinder is discharged;
the muffler defines an outer contour of the muffler chamber by an end face portion which is a face portion on one end side in the axial direction of the rotating shaft, a flange portion which is a face portion on the other end side in the axial direction of the rotating shaft, and a side face portion which cylindrically connects the end face portion and the flange portion around the entire circumferential direction of the rotating shaft, and has recesses formed by recessing the end face portion and the side face portion into the inside of the muffler chamber,
the flange portion has a recessed portion formed by recessing an end face on one end side in an axial direction of the rotating shaft, and into which the discharge valve and the valve guard are assembled,
the recess is disposed so as to intersect with a longitudinal direction of the discharge valve and overlap with the recessed portion when the recess is projected onto the flange portion from the axial direction of the rotating shaft,
the recess includes a first surface, a second surface, a third surface, and a fourth surface;
the first surface portion and the second surface portion are parallel to a predetermined imaginary plane that includes an axis of the rotation shaft and intersects with a longitudinal direction of the discharge valve,
the third surface portion and the fourth surface portion are continuous with each other, the third surface portion connects between the first surface portion and the second surface portion on one side in the axial direction of the rotating shaft, and the fourth surface portion connects between the first surface portion and the second surface portion on the other side in the axial direction of the rotating shaft,
the third surface portion has a through hole through which a first fastener for fixing the muffler to the boss portion is inserted,
the first surface portion and the second surface portion face each other at a distance not allowing interference with the first fixing device. The compressor according to claim 1 , wherein the collar portion has a plurality of through holes through which second fasteners for fastening the collar portion to the cylinder via the flange portion are inserted. A compressor according to claim 1 or 2 ;
a condenser connected to the compressor;
an expansion device connected to the condenser;
an evaporator connected to the expansion device.

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