JP6137166B2 - Scroll compressor and refrigeration equipment - Google Patents

Description

  The present invention relates to a scroll compressor and a refrigeration apparatus.

  In a refrigeration system equipped with a scroll compressor, when the compressor stops during the operation of the refrigeration cycle, it is movable by the pressure difference between the high-pressure refrigerant gas on the compressor discharge side and the low-pressure refrigerant gas on the compressor suction side The scroll rotates in the direction opposite to that during refrigerant compression. When the movable scroll rotates in the reverse direction, the volume of the compression chamber inside the compressor increases, and the refrigerant gas in the compression chamber expands. As a result, when the pressure in the compression chamber is lower than the pressure in the space on the compressor suction side, the winding end portion of the movable scroll wrap (vortex portion) receives a force due to the differential pressure, and the movable scroll wrap may be damaged. is there.

  Conventionally, as a method for suppressing the reverse rotation of the movable scroll, a configuration in which a backflow prevention mechanism such as a check valve is provided in the compressor discharge side space is used. However, the flow path resistance on the discharge side of the compressor increases, and the efficiency of the compressor during normal operation may be reduced.

  Moreover, as disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 2014-101858), a configuration in which a backflow prevention mechanism such as a check valve is provided in a space on the compressor suction side may be used. However, even in this case, the movable scroll may reversely rotate in the process of equalizing the pressure inside the compressor. And, in the pressure equalization process, the refrigerant gas in the compression chamber expands and the pressure in the compression chamber decreases, and the pressure in the space between the compression chamber closing part on the suction side and the backflow prevention mechanism increases, There is a case where the winding end portion of the movable scroll wrap receives a force due to the differential pressure.

  The objective of this invention is providing the scroll compressor which can suppress the damage resulting from the differential pressure which generate | occur | produces inside at the time of a stop, and a freezing apparatus provided with the same.

A scroll compressor according to a first aspect of the present invention includes a compression mechanism, a suction space forming part, and a communication path forming part. The compression mechanism has a fixed scroll and a movable scroll. The movable scroll is engaged with the fixed scroll to form a compression chamber in which the refrigerant is compressed. The suction space forming part forms a suction space for introducing the refrigerant into the compression chamber. The communication path forming portion forms a communication path that connects the compression chamber and the suction space. The communication path is provided with a backflow prevention mechanism. The backflow prevention mechanism only allows the refrigerant to flow from the suction space to the compression chamber. The communication path connects the suction chamber and the compression chamber immediately after being closed from the suction space after the refrigerant is introduced.

  In the scroll compressor according to the first aspect, the refrigerant gas in the suction space whose pressure has increased in the pressure equalization process is supplied to the compression chamber, which has become lower in pressure than the suction space due to the reverse rotation of the movable scroll when stopped. Introduced to reduce the pressure difference between the compression chamber and the suction space. Thereby, the force applied to the winding end portion of the movable scroll wrap is reduced, and damage to the movable scroll wrap is suppressed. Therefore, the scroll compressor which concerns on a 1st viewpoint can suppress the damage resulting from the differential pressure which generate | occur | produces inside at the time of a stop.

In the scroll compressor according to the first aspect, the communication path is connected to a closed compression chamber that is a compression chamber immediately after being closed from the suction space after the refrigerant is introduced. The winding end portion of the wrap of the movable scroll receives the pressure of the refrigerant in the closed compression chamber and the pressure of the refrigerant in the suction space. The pressure difference between the closed compression chamber and the suction space is reduced by the communication path. For this reason, the force applied to the winding end portion of the movable scroll wrap is reduced by the communication path connecting the closed compression chamber and the suction space.

A scroll compressor according to a second aspect of the present invention is the scroll compressor according to the first aspect, wherein the compression mechanism discharges the refrigerant compressed in the compression chamber to an external space of the compression mechanism through the discharge hole. The discharge hole is always in communication with the external space.

  A scroll compressor according to a third aspect of the present invention is the scroll compressor according to the first aspect or the second aspect, and the backflow prevention mechanism is a check valve.

  A scroll compressor according to a fourth aspect of the present invention is the scroll compressor according to any one of the first to third aspects, wherein the suction space forming portion and the communication path forming portion are included in the compression mechanism.

  A scroll compressor according to a fifth aspect of the present invention is the scroll compressor according to any one of the first to third aspects, wherein the suction space forming portion includes a suction pipe connected to the compression mechanism, The communication path forming portion includes a communication pipe connected to the suction pipe.

  A refrigeration apparatus according to a sixth aspect of the present invention includes the scroll compressor according to any one of the first to fifth aspects, a condenser, an expansion mechanism, and an evaporator.

  Since the refrigeration apparatus according to the sixth aspect includes the scroll compressor according to the first aspect to the fifth aspect, the reliability during operation can be improved.

  The scroll compressor which concerns on the 1st viewpoint thru | or 5th viewpoint of this invention can suppress the damage resulting from the differential pressure which generate | occur | produces inside at the time of a stop.

  The refrigeration apparatus according to the sixth aspect of the present invention can improve reliability during operation.

It is a refrigerant circuit figure of the refrigerating device concerning a 1st embodiment. It is a longitudinal cross-sectional view of a scroll compressor. It is a bottom view of a fixed scroll. It is a top view of a movable scroll. It is a bottom view of the fixed scroll in which the second wrap and the compression chamber of the movable scroll are shown. It is a sectional side view of a compression mechanism. It is a figure which shows the positional relationship of the 1st lap of a fixed scroll, and the 2nd lap of a movable scroll. It is a figure which shows the positional relationship of the 1st lap of a fixed scroll, and the 2nd lap of a movable scroll. It is a figure which shows the positional relationship of the 1st lap of a fixed scroll, and the 2nd lap of a movable scroll. It is a sectional side view of the compression mechanism which concerns on 2nd Embodiment.

<First Embodiment>
A scroll compressor according to a first embodiment of the present invention and a refrigeration apparatus including the scroll compressor will be described with reference to the drawings.

(1) Structure of refrigeration apparatus The refrigeration apparatus 100 of this embodiment is demonstrated. The refrigeration apparatus 100 is, for example, an air conditioner. FIG. 1 is a refrigerant circuit diagram of the refrigeration apparatus 100. The refrigeration apparatus 100 mainly includes a scroll compressor 101, a four-way switching valve 102, an outdoor heat exchanger 103, an expansion mechanism 104, and an indoor heat exchanger 105. In FIG. 1, the solid arrow represents the refrigerant flow during the cooling operation, and the dotted arrow represents the refrigerant flow during the heating operation.

  The refrigeration cycle of the refrigeration apparatus 100 during the cooling operation will be described. First, the scroll compressor 101 compresses the low-pressure gas refrigerant and discharges the high-pressure gas refrigerant. The refrigerant discharged from the scroll compressor 101 passes through the four-way switching valve 102 and is supplied to the outdoor heat exchanger 103. The outdoor heat exchanger 103 condenses the high-pressure gas refrigerant and discharges the high-pressure liquid refrigerant. The refrigerant discharged from the outdoor heat exchanger 103 passes through the expansion valve, which is the expansion mechanism 104, becomes a low-pressure gas-liquid mixed refrigerant, and is supplied to the indoor heat exchanger 105. The indoor heat exchanger 105 evaporates the liquid refrigerant contained in the low-pressure gas-liquid mixed refrigerant and discharges the low-pressure gas refrigerant. The low-pressure gas refrigerant discharged from the indoor heat exchanger 105 is supplied again to the scroll compressor 101.

  During the cooling operation, the outdoor heat exchanger 103 functions as a condenser, and the indoor heat exchanger 105 functions as an evaporator. In this case, the room is cooled by the latent heat of vaporization of the refrigerant generated in the indoor heat exchanger 105. On the other hand, during the heating operation, by switching the four-way switching valve 102, the outdoor heat exchanger 103 functions as an evaporator and the indoor heat exchanger 105 functions as a condenser. In this case, the room is heated by the condensation latent heat of the refrigerant generated in the indoor heat exchanger 105.

(2) Configuration of Scroll Compressor Next, the scroll compressor 101 provided in the refrigeration apparatus 100 will be described. The scroll compressor 101 is a compressor that compresses a refrigerant by two scroll members having spiral wraps that mesh with each other. The scroll compressor 101 is a high and low pressure dome type scroll compressor.

  FIG. 2 is a longitudinal sectional view of the scroll compressor 101. The scroll compressor 101 mainly includes a casing 10, a compression mechanism 15, a housing 23, a drive motor 16, a lower bearing 60, a crankshaft 17, a suction pipe 19, and a discharge pipe 20. The scroll compressor 101 has a role of compressing the refrigerant gas in the refrigerant circuit of the refrigeration apparatus 100. Next, each component of the scroll compressor 101 will be described.

(2-1) Casing The casing 10 includes a substantially cylindrical trunk casing portion 11, a bowl-shaped upper wall portion 12 that is airtightly welded to the upper end portion of the trunk casing portion 11, and the trunk casing portion 11. And a bowl-shaped bottom wall portion 13 which is welded in an airtight manner to the lower end portion of the base plate. The casing 10 is formed of a rigid member that is unlikely to be deformed or damaged when pressure or temperature changes inside or outside the casing 10. The casing 10 is installed so that the substantially cylindrical axial direction of the body casing portion 11 is along the vertical direction.

  Inside the casing 10, a compression mechanism 15, a housing 23 disposed below the compression mechanism 15, a drive motor 16 disposed below the housing 23, and a crankshaft 17 disposed to extend in the vertical direction. Etc. are housed. A suction pipe 19 and a discharge pipe 20 are welded to the wall portion of the casing 10 in an airtight manner.

  An oil sump space 10 a in which lubricating oil is stored is formed at the bottom of the casing 10. Lubricating oil is used to keep the lubricity of sliding parts such as the compression mechanism 15 good during the operation of the scroll compressor 101.

(2-2) Compression mechanism The compression mechanism 15 is accommodated in the casing 10, sucks and compresses the low-temperature and low-pressure refrigerant gas, and discharges the high-temperature and high-pressure refrigerant gas (hereinafter referred to as "compressed refrigerant"). . The compression mechanism 15 is mainly composed of a fixed scroll 24 and a movable scroll 26. The fixed scroll 24 is fixed with respect to the casing 10. The movable scroll 26 performs a revolving motion with respect to the fixed scroll 24. FIG. 3 is a plan view of the fixed scroll 24 as viewed from below in the vertical direction. FIG. 4 is a plan view of the movable scroll 26 viewed from above in the vertical direction.

  The fixed scroll 24 includes a first end plate 24a and an involute-shaped first wrap 24b formed upright on the first end plate 24a. A main suction hole 24c is formed in the first end plate 24a. The main suction hole 24c is a space that connects the suction pipe 19 and a compression chamber 40 described later. The main suction hole 24 c forms a suction space for introducing a low-temperature and low-pressure refrigerant gas from the suction pipe 19 into the compression chamber 40. A discharge hole 41 is formed in the central portion of the first end plate 24a, and an enlarged recess 42 communicating with the discharge hole 41 is formed on the upper surface of the first end plate 24a. The enlarged recess 42 is a space recessed in the upper surface of the first end plate 24a. A lid 44 is fixed to the upper surface of the fixed scroll 24 with bolts 44 a so as to close the enlarged recess 42. The fixed scroll 24 and the lid 44 are tightly sealed through a gasket (not shown). A muffler space 45 that silences the operation sound of the compression mechanism 15 is formed by covering the enlarged recess 42 with the lid 44. The fixed scroll 24 is formed with a first compressed refrigerant channel 46 that communicates with the muffler space 45 and opens on the lower surface of the fixed scroll 24. As shown in FIG. 3, a C-shaped oil groove 24 e is formed on the lower surface of the first end plate 24 a.

  The movable scroll 26 has a second end plate 26a and an involute-shaped second wrap 26b formed upright on the second end plate 26a. An upper end bearing 26c is formed at the center of the lower surface of the second end plate 26a. The movable scroll 26 has an oil supply hole 63 formed therein. The oil supply pore 63 communicates the outer peripheral portion of the upper surface of the second end plate 26a and the space inside the upper end bearing 26c. FIG. 4 shows a winding end portion 26d that is an outer end portion of the second wrap 26b.

  The fixed scroll 24 and the movable scroll 26 are surrounded by the first end plate 24a, the first wrap 24b, the second end plate 26a, and the second wrap 26b when the first wrap 24b and the second wrap 26b are engaged with each other. A compression chamber 40 that is a space is formed. The volume of the compression chamber 40 is gradually reduced by the revolving motion of the movable scroll 26. During the revolution of the movable scroll 26, the lower surfaces of the first end plate 24 a and the first wrap 24 b of the fixed scroll 24 slide with the upper surfaces of the second end plate 26 a and the second wrap 26 b of the movable scroll 26. Hereinafter, the surface of the fixed scroll 24 that slides with the movable scroll 26 is referred to as a thrust sliding surface 24d. FIG. 5 is a bottom view of the fixed scroll 24 in which the position of the second wrap 26 b of the movable scroll 26 and the compression chamber 40 are shown. In FIG. 5, the hatched area represents the thrust sliding surface 24 d of the fixed scroll 24. In FIG. 5, the outer edge of the thrust sliding surface 24d represents the locus of the outer edge of the second end plate 26a of the revolving movable scroll 26. As shown in FIG. 5, the oil groove 24e of the fixed scroll 24 is formed on the lower surface of the first end plate 24a so as to be accommodated in the thrust sliding surface 24d.

  FIG. 6 is a side sectional view of the compression mechanism 15. FIG. 6 schematically shows the suction pipe 19 connected to the main suction hole 24c. The first end plate 24a of the fixed scroll 24 is formed with a communication path 24h that connects the compression chamber 40 and the main suction hole 24c. A backflow prevention mechanism 25 is provided in the communication path 24h. The backflow prevention mechanism 25 permits the refrigerant flow from the main suction hole 24c to the compression chamber 40 and prohibits the refrigerant flow from the compression chamber 40 to the main suction hole 24c. The backflow prevention mechanism 25 is, for example, a check valve. In the present embodiment, the first end plate 24a of the fixed scroll 24 is a member that forms the main suction hole 24c and the communication path 24h.

  7 to 9 are views showing the positional relationship between the first wrap 24 b of the fixed scroll 24 and the second wrap 26 b of the movable scroll 26. During normal operation of the scroll compressor 101, that is, when the refrigerant is compressed by the compression mechanism 15, the second wrap is sequentially performed in the order of FIGS. 7, 8, 9, and 7 as the movable scroll 26 revolves. The position of 26b changes periodically. The compression chamber 40 of the compression mechanism 15 includes a first compression chamber 40a, a second compression chamber 40b, and a third compression chamber 40c. As the movable scroll 26 revolves, the refrigerant is introduced into the first compression chamber 40a and the second compression chamber 40b from the main suction hole 24c, and then the volumes of the first compression chamber 40a and the second compression chamber 40b are independent from each other. To decrease. Thereby, the refrigerant is compressed in the first compression chamber 40a and the second compression chamber 40b. The first compression chamber 40a and the second compression chamber 40b join together in the process of compressing the refrigerant to become the third compression chamber 40c. In the third compression chamber 40 c, the refrigerant is further compressed by the revolving motion of the movable scroll 26. The refrigerant compressed in the third compression chamber 40 c is introduced into the discharge hole 41.

In FIG. 7, the first compression chamber 40a immediately after being closed from the main suction hole 24c after the refrigerant is introduced is shown as a hatched region. In FIG. 8, the second compression chamber 40b immediately after being closed from the main suction hole 24c after the refrigerant is introduced is shown as a hatched region. Hereinafter, if necessary, the first compression chamber 40a shown as the hatching region in FIG. 7 is referred to as a first closed compression chamber 40a, and the second compression chamber 40b shown as the hatching region in FIG. It is called a two-closed compression chamber 40b. The communication path 24h of the fixed scroll 24 opens to a position where it can communicate with both the first closed compression chamber 40a and the second closed compression chamber 40b during the revolution of the movable scroll 26. That is, the communication path 24h is opened in a region where the hatching region in FIG. 7 and the hatching region in FIG. 8 overlap.

(2-3) Housing The housing 23 is disposed below the compression mechanism 15. The outer peripheral surface of the housing 23 is joined to the inner surface of the casing 10 in an airtight manner. Thereby, the internal space of the casing 10 is partitioned into a high-pressure space S <b> 1 below the housing 23 and an upper space S <b> 2 that is a space above the housing 23. The housing 23 mounts a fixed scroll 24 and sandwiches the movable scroll 26 together with the fixed scroll 24 via an Oldham joint 39. The Oldham coupling 39 is an annular member for preventing the movable scroll 26 from rotating. A second compressed refrigerant channel 48 is formed through the outer periphery of the housing 23 in the vertical direction. The second compressed refrigerant channel 48 communicates with the first compressed refrigerant channel 46 on the upper surface of the housing 23, and communicates with the high-pressure space S <b> 1 on the lower surface of the housing 23.

  A crank chamber S <b> 3 is recessed in the upper surface of the housing 23. A housing through hole 31 is formed in the housing 23. The housing through hole 31 penetrates the housing 23 in the vertical direction from the center of the bottom surface of the crank chamber S3 to the center of the lower surface of the housing 23. Hereinafter, a portion that is a part of the housing 23 and in which the housing through hole 31 is formed is referred to as an upper bearing 32. The housing 23 is formed with an oil return passage 23a that connects the high-pressure space S1 near the inner surface of the casing 10 and the crank chamber S3.

(2-4) Drive Motor The drive motor 16 is a brushless DC motor disposed below the housing 23. The drive motor 16 mainly includes a stator 51 that is fixed to the inner surface of the casing 10 and a rotor 52 that is disposed with an air gap provided inside the stator 51.

  The outer peripheral surface of the stator 51 is provided with a plurality of core cut portions that are notched from the upper end surface of the stator 51 to the lower end surface and at a predetermined interval in the circumferential direction. The core cut portion forms a motor cooling passage 55 that extends in the vertical direction between the body casing portion 11 and the stator 51.

  The rotor 52 is connected to the crankshaft 17 that passes through the center of rotation in the vertical direction. The rotor 52 is connected to the compression mechanism 15 via the crankshaft 17.

(2-5) Lower Bearing The lower bearing 60 is disposed below the drive motor 16. The outer peripheral surface of the lower bearing 60 is joined to the inner surface of the casing 10 in an airtight manner. The lower bearing 60 supports the crankshaft 17. An oil separation plate 73 is attached to the upper end of the lower bearing 60. The oil separation plate 73 is a flat plate member accommodated in the casing 10. The oil separation plate 73 is fixed to the upper end surface of the lower bearing 60.

(2-6) Crankshaft The crankshaft 17 is accommodated in the casing 10. The crankshaft 17 is disposed such that its axial direction is along the vertical direction. The crankshaft 17 has a shape in which the shaft center of the upper end portion thereof is slightly eccentric with respect to the shaft center of the portion excluding the upper end portion. The crankshaft 17 has a balance weight 18. The balance weight 18 is fixed in close contact with the crankshaft 17 at a height position below the housing 23 and above the drive motor 16.

  The crankshaft 17 passes through the rotation center of the rotor 52 in the vertical direction and is connected to the rotor 52. The crankshaft 17 is connected to the movable scroll 26 by fitting the upper end portion of the crankshaft 17 into the upper end bearing 26c. The crankshaft 17 is supported by the upper bearing 32 and the lower bearing 60.

  The crankshaft 17 has a main oil supply passage 61 extending in the axial direction thereof. The upper end of the main oil supply passage 61 communicates with an oil chamber 83 formed by the upper end surface of the crankshaft 17 and the lower surface of the second end plate 26a. The oil chamber 83 communicates with the thrust sliding surface 24d and the oil groove 24e via the oil supply hole 63 of the second end plate 26a, and finally communicates with the low pressure space S2 via the compression chamber 40. The lower end of the main oil supply passage 61 is immersed in the lubricating oil in the oil reservoir space 10a.

  The crankshaft 17 has a first sub oil supply path 61 a, a second sub oil supply path 61 b, and a third sub oil supply path 61 c that branch from the main oil supply path 61. The first sub oil supply path 61a, the second sub oil supply path 61b, and the third sub oil supply path 61c extend in the horizontal direction. The first sub oil supply passage 61 a is open to the sliding surface between the crankshaft 17 and the upper end bearing 26 c of the movable scroll 26. The second sub oil supply passage 61 b opens in the sliding surface between the crankshaft 17 and the upper bearing 32 of the housing 23. The third sub oil supply passage 61 c is open on the sliding surface between the crankshaft 17 and the lower bearing 60.

(2-7) Suction Pipe The suction pipe 19 is a pipe for introducing the refrigerant of the refrigerant circuit from the outside of the casing 10 to the compression mechanism 15. The suction pipe 19 is fitted into the upper wall portion 12 of the casing 10 in an airtight manner. The suction pipe 19 penetrates the upper space S <b> 2 in the vertical direction, and an inner end portion is fitted into the main suction hole 24 c of the fixed scroll 24.

(2-8) Discharge Pipe The discharge pipe 20 is a pipe for discharging the compressed refrigerant from the high-pressure space S1 to the outside of the casing 10. The discharge pipe 20 is fitted in the body casing part 11 of the casing 10 in an airtight manner. The discharge pipe 20 penetrates the high-pressure space S1 in the horizontal direction. The opening 20 a of the discharge pipe 20 in the casing 10 is located in the vicinity of the housing 23.

(3) Operation of Scroll Compressor The operation of the scroll compressor 101 according to this embodiment will be described. Initially, the flow of the refrigerant | coolant which circulates through a refrigerant circuit provided with the scroll compressor 101 is demonstrated. Next, the flow of the lubricating oil inside the scroll compressor 101 will be described.

(3-1) Flow of refrigerant First, the drive motor 16 is driven to rotate the rotor 52. As a result, the crankshaft 17 fixed to the rotor 52 rotates. The rotational movement of the crankshaft 17 is transmitted to the movable scroll 26 through the upper end bearing 26c. The shaft center of the upper end portion of the crankshaft 17 is eccentric with respect to the shaft rotational movement center of the crankshaft 17. The movable scroll 26 is prevented from rotating by the Oldham joint 39. Thereby, the movable scroll 26 performs a revolving motion with respect to the fixed scroll 24 without rotating.

  The low-temperature and low-pressure refrigerant before being compressed is supplied from the suction pipe 19 to the compression chamber 40 of the compression mechanism 15 via the main suction hole 24c. By the revolving motion of the movable scroll 26, the compression chamber 40 moves from the outer peripheral portion of the fixed scroll 24 toward the center portion while gradually reducing the volume. As a result, the refrigerant in the compression chamber 40 is compressed to become a compressed refrigerant. The compressed refrigerant is discharged from the discharge hole 41 to the muffler space 45, and then discharged to the high-pressure space S1 via the first compressed refrigerant channel 46 and the second compressed refrigerant channel 48. Then, the compressed refrigerant descends the motor cooling passage 55 and reaches the high pressure space S <b> 1 below the drive motor 16. Then, the compressed refrigerant reverses the flow direction and raises the air gap between the other motor cooling passage 55 and the drive motor 16. Finally, the compressed refrigerant is discharged from the discharge pipe 20 to the outside of the scroll compressor 101.

(3-2) Flow of Lubricating Oil First, when the motor 16 is driven, the rotor 52 rotates, whereby the crankshaft 17 rotates. When the compression mechanism 15 is driven by the rotation of the crankshaft 17 and the compressed refrigerant is discharged into the high-pressure space S1, the pressure in the high-pressure space S1 increases. Further, the upper end of the main oil supply passage 61 communicates with the low pressure space S <b> 2 through the oil chamber 83 and the oil supply pores 63. Thereby, a differential pressure is generated between the upper end and the lower end of the main oil supply passage 61. As a result, the lubricating oil stored in the oil reservoir space 10 a is sucked from the lower end of the main oil supply passage 61 due to the differential pressure, and rises in the main oil supply passage 61 toward the oil chamber 83.

  Most of the lubricating oil that moves up the main oil supply passage 61 is sequentially divided into the third sub oil supply passage 61c, the second sub oil supply passage 61b, and the first sub oil supply passage 61a. The lubricating oil flowing through the third sub oil supply passage 61c lubricates the sliding surfaces of the crankshaft 17 and the lower bearing 60, and then is supplied to the high pressure space S1 and returned to the oil reservoir space 10a. The lubricating oil flowing through the second auxiliary oil supply passage 61b is supplied to the high-pressure space S1 and the crank chamber S3 after lubricating the sliding surface between the crankshaft 17 and the upper bearing 32 of the housing 23. The lubricating oil supplied to the high pressure space S1 is returned to the oil sump space 10a. The lubricating oil supplied to the crank chamber S3 is supplied to the high-pressure space S1 via the oil return passage 23a of the housing 23 and returned to the oil reservoir space 10a. Lubricating oil flowing through the first auxiliary oil supply passage 61a lubricates the sliding surface between the crankshaft 17 and the upper end bearing 26c of the movable scroll 26, and is then supplied to the crank chamber S3. Returned to the space 10a.

  The lubricating oil that has risen to the upper end in the main oil supply passage 61 and has reached the oil chamber 83 flows through the oil supply holes 63 and is supplied to the oil groove 24e due to the differential pressure. Part of the lubricating oil supplied to the oil groove 24e leaks into the low pressure space S2 and the compression chamber 40 while sealing the thrust sliding surface 24d. At this time, the high-temperature and high-pressure lubricating oil originally heats the refrigerant gas before compression existing in the low-pressure space S2 and the compression chamber 40. The lubricating oil that has flowed into the compression chamber 40 is mixed with the compressed refrigerant in the form of minute oil droplets. The lubricating oil mixed in the compressed refrigerant is discharged from the compression chamber 40 to the high-pressure space S1 through the same path as the compressed refrigerant. Thereafter, the lubricating oil collides with the oil separation plate 73 after descending the motor cooling passage 55 together with the compressed refrigerant. The lubricating oil adhering to the oil separation plate 73 falls in the high pressure space S1 and reaches the oil pool space 10a.

(4) Features of Scroll Compressor The refrigeration apparatus 100 according to the present embodiment can prevent the compression mechanism 15 from being damaged due to the operation stop of the scroll compressor 101. The reason will be described below.

  When the operation of the scroll compressor 101 is stopped, the revolving motion of the movable scroll 26 is stopped. At the moment when the movable scroll 26 stops, the high-pressure refrigerant gas compressed in the compression chamber 40 exists in the discharge hole 41 of the compression mechanism 15, and is introduced into the compression chamber 40 in the main suction hole 24 c of the compression mechanism 15. There is low-pressure refrigerant gas before it is used. Therefore, due to the pressure difference between the discharge hole 41 and the main suction hole 24c, the movable scroll 26 performs a reverse rotational motion that revolves in a direction opposite to the revolution direction during refrigerant compression. Due to the reverse rotation of the movable scroll 26, the volume of the compression chamber 40 (the first compression chamber 40a and the second compression chamber 40b) increases. When the volume of the compression chamber 40 increases, the refrigerant in the compression chamber 40 expands, so that the pressure of the refrigerant in the compression chamber 40 decreases. On the other hand, the reverse rotation of the movable scroll 26 causes a part of the refrigerant in the compression chamber 40 to flow into the main suction hole 24c, so that the pressure of the refrigerant in the main suction hole 24c increases.

  In the present embodiment, a communication path 24 h is formed in the first end plate 24 a of the fixed scroll 24. The communication path 24h connects the first closed compression chamber 40a and the main suction hole 24c, or connects the second closed compression chamber 40b and the main suction hole 24c. In addition, a reverse flow that allows only the refrigerant flow from the main suction hole 24c to the first closed compression chamber 40a and the refrigerant flow from the main suction hole 24c to the second closed compression chamber 40b is allowed to flow through the communication path 24h. A prevention mechanism 25 is provided. Therefore, when the pressure of the refrigerant in the first closed compression chamber 40a or the second closed compression chamber 40b becomes lower than the refrigerant pressure in the main suction hole 24c due to the reverse rotational movement of the movable scroll 26, the main suction hole 24c. Through the communication passage 24h, the refrigerant flows toward the first closed compression chamber 40a or the second closed compression chamber 40b. Thereby, the pressure difference between the main suction hole 24c and the first closed compression chamber 40a or the pressure difference between the main suction hole 24c and the second closed compression chamber 40b is reduced.

  When the movable scroll 26 rotates in the reverse direction due to the operation stop of the scroll compressor 101, the movable scroll 26 may reach the position where the first closed compression chamber 40a or the second closed compression chamber 40b is formed. At this time, the pressure of the refrigerant in the first closed compression chamber 40a or the second closed compression chamber 40b and the pressure of the refrigerant in the main suction hole 24c are applied to the winding end portion 26d of the second wrap 26b of the movable scroll 26. It depends.

  However, since the pressure difference between the first closed compression chamber 40a or the second closed compression chamber 40b and the main suction hole 24c is reduced by the communication passage 24h, the winding end of the second wrap 26b is caused by the pressure difference. The magnitude of the force acting on the portion 26d is reduced. If the winding end portion 26d of the second wrap 26b receives a force when the movable scroll 26 is rotating in the reverse direction, the second wrap 26b collides with the fixed scroll 24, and the fixed scroll 24 and the movable scroll 26 are damaged. There is a fear. Therefore, damage to the fixed scroll 24 and the movable scroll 26 can be suppressed by reducing the force applied to the winding end portion 26d of the second lap 26b when the operation of the scroll compressor 101 is stopped by the communication passage 24h. Therefore, the scroll compressor 101 can suppress damage caused by the differential pressure generated inside when the operation is stopped. Further, by providing the scroll compressor 101, the reliability during operation of the refrigeration apparatus 100 is improved.

  Note that during the normal operation of the scroll compressor 101, that is, when the refrigerant is compressed by the compression mechanism 15, the pressure of the refrigerant in the compression chamber 40 is higher than the pressure of the refrigerant in the main suction hole 24c. However, since the backflow prevention mechanism 25 prohibits the flow of the refrigerant from the compression chamber 40 to the main suction hole 24c, the refrigerant does not flow from the compression chamber 40 toward the main suction hole 24c via the communication path 24h.

Second Embodiment
A scroll compressor according to a second embodiment of the present invention will be described. Since the basic configuration, operation, and features of the present embodiment are the same as those of the scroll compressor according to the first embodiment, differences from the first embodiment will be mainly described.

  FIG. 10 is a side sectional view of the compression mechanism 115 according to the present embodiment. In FIG. 10, the same reference numerals are used for elements having the same configuration and function as the compression mechanism 15 of the first embodiment. The compression mechanism 115 includes a fixed scroll 124 and a movable scroll 126. The fixed scroll 124 includes a first end plate 124a and a first wrap 124b. The movable scroll 126 has a second end plate 126a and a second wrap 126b. A main suction hole 124c is formed in the first end plate 124a. A suction pipe 119 is fitted in the main suction hole 124c. A compression chamber 140 is formed inside the compression mechanism 115. The basic configuration described above is the same as that of the compression mechanism 15 of the first embodiment.

  In the first embodiment, the fixed scroll 24 is formed with a communication path 24 h that connects the main suction hole 24 c and the compression chamber 40. That is, the communication path 24 h is built in the compression mechanism 15. However, in the present embodiment, as shown in FIG. 10, the first end plate 124a is formed with a communication path 124h communicating with the compression chamber 140, and the communication pipe 124i connected to the communication path 124h includes a compression mechanism. 115 is provided outside. The communication pipe 124 i is connected to the suction pipe 119. Since the suction pipe 119 communicates with the main suction hole 124c, the passage formed by the communication path 124h and the communication pipe 124i has the same function as the communication path 24h of the first embodiment. The communication pipe 124 i is disposed inside the casing 10. However, a part of the communication pipe 124 i may be disposed outside the casing 10 as necessary.

  Further, a backflow prevention mechanism 125 is provided in the communication path 124h. The backflow prevention mechanism 125 permits the refrigerant flow from the suction pipe 119 to the compression chamber 140 and prohibits the refrigerant flow from the compression chamber 140 to the suction pipe 119. The backflow prevention mechanism 125 is, for example, a check valve. That is, the backflow prevention mechanism 125 has the same function as the backflow prevention mechanism 25 of the first embodiment.

  In the present embodiment, as in the first embodiment, the pressure difference between the suction pipe 119 and the compression chamber 140 that is generated when the movable scroll 126 is reversely rotated is reduced by the communication path 124h and the communication pipe 124i. The Therefore, the magnitude of the force acting on the winding end portion of the second wrap 126b due to this pressure difference is reduced, so that damage to the fixed scroll 124 and the movable scroll 126 is suppressed. Therefore, the scroll compressor provided with the compression mechanism 115 can suppress damage due to the differential pressure generated inside when the operation is stopped.

<Modification>
Modifications applicable to the compressor according to the embodiment of the present invention will be described.

(1) Modification A
In the first embodiment, the communication path 24 h is connected to the main suction hole 24 c of the fixed scroll 24. A suction pipe 19 is fitted in the main suction hole 24c. However, the main suction hole 24 c or the suction pipe 19 may further be provided with a backflow prevention mechanism similar to the backflow prevention mechanism 25. When the backflow prevention mechanism is provided in the main suction hole 24c, the communication path 24h is formed in the fixed scroll 24 so as to open in a space between the backflow prevention mechanism of the main suction hole 24c and the compression chamber 40.

(2) Modification B
In the second embodiment, the communication pipe 124 i is attached to the suction pipe 119. However, the communication pipe 124i may be connected to another space as long as the refrigerant flows before being compressed by the compression mechanism 115. For example, the communication pipe 124i may be connected to a pipe between the scroll compressor including the compression mechanism 115 and the evaporator. In FIG. 1, the evaporator during the cooling operation is the indoor heat exchanger 105, and the evaporator during the heating operation is the outdoor heat exchanger 103.

(3) Modification C
In the second embodiment, the backflow prevention mechanism 125 is provided in the communication path 124h. However, the backflow prevention mechanism 125 may be attached to the communication pipe 124i.

  The scroll compressor which concerns on this invention can suppress the damage resulting from the differential pressure which generate | occur | produces inside at the time of a stop.

DESCRIPTION OF SYMBOLS 15 Compression mechanism 19 Suction pipe 24 Fixed scroll 26 Movable scroll 40 Compression chamber 24a 1st end plate (suction space formation part)
24a First end plate (communication path forming part)
24c Main suction hole (suction space)
24h Communication path 25 Backflow prevention mechanism 100 Refrigeration apparatus 101 Scroll compressor 103 Outdoor heat exchanger (condenser during cooling operation)
103 Outdoor heat exchanger (evaporator during heating operation)
104 Expansion mechanism 105 Indoor heat exchanger (evaporator during cooling operation)
105 Indoor heat exchanger (condenser during heating operation)
119 Suction pipe 124i Communication pipe

JP 2014-101858 A

Claims (6)

A compression mechanism (15) having a fixed scroll (24) and a movable scroll (26) that forms a compression chamber (40) meshed with the fixed scroll and compressed by a refrigerant;
A suction space forming part (24a) for forming a suction space (24c) for introducing the refrigerant into the compression chamber;
A communication path forming portion (24a) that forms a communication path (24h) connecting the compression chamber and the suction space;
With
The communication path is provided with a backflow prevention mechanism (25) that permits only the flow of the refrigerant from the suction space to the compression chamber ,
The communication path connects the compression space and the suction space immediately after being closed from the suction space after the refrigerant is introduced,
Scroll compressor (101). The compression mechanism discharges the refrigerant compressed in the compression chamber to an external space (45) of the compression mechanism through a discharge hole (41).
  The discharge hole is always in communication with the external space,
The scroll compressor according to claim 1. The backflow prevention mechanism is a check valve.
The scroll compressor according to claim 1 or 2. The suction space forming part and the communication path forming part are included in the compression mechanism,
The scroll compressor according to any one of claims 1 to 3. The suction space forming part includes a suction pipe (119) connected to the compression mechanism,
The communication path forming portion includes a communication pipe (124i) connected to the suction pipe.
The scroll compressor according to any one of claims 1 to 3. A scroll compressor according to any one of claims 1 to 5,
A condenser (103, 105);
An expansion mechanism (104);
An evaporator (105, 103);
A refrigeration apparatus (100) comprising:

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