Scroll compressor

Abstract

This scroll compressor comprises a compression mechanism that compresses a refrigerant, and a rotary shaft that drives the compression mechanism. The compression mechanism includes a first compression part provided such that the rotary shaft passes therethrough, a second compression part provided such that the rotary shaft passes therethrough and arranged side by side with the first compression part in an axial direction of the rotation shaft, and a thrust plate. The first compression part includes a first fixed scroll having a first fixed base plate and a first fixed spiral, and a first rocking scroll having a first rocking base plate and a first rocking spiral that engages with the first fixed spiral to form a first compression chamber. The second compression part includes a second fixed scroll having a second fixed base plate and a second fixed spiral, and a second rocking scroll having a second rocking base plate and a second rocking spiral that engages with the second fixed spiral to form a second compression chamber. The back surface of the first rocking base plate and the back surface of the second rocking base plate are disposed facing each other with the thrust plate interposed therebetween.

Description

Scroll Compressor

[0001] The present disclosure relates to a scroll compressor used in an air conditioner, a refrigerator, or the like.

[0002] Conventionally, there has been a scroll compressor including an orbiting scroll having an orbiting spiral formed on both sides of an orbiting base plate, and two fixed scrolls arranged on both sides of the orbiting scroll, each having a fixed spiral formed on the fixed base plate that meshes with the orbiting spiral, thereby forming two compression chambers (see, for example, Patent Document 1). The scroll compressor of Patent Document 1 is configured such that a rotating shaft penetrates one of the two fixed scrolls and the orbiting scroll, and the orbiting scroll connected to an eccentric shaft portion of the rotating shaft orbits due to rotation of the rotating shaft, thereby compressing refrigerant inside the two compression chambers.

[0003] Japanese Patent Application Publication No. 10-110690

[0004] The scroll compressor of Patent Document 1 has an orbiting scroll formed on both sides of the orbiting base plate of the orbiting scroll. Therefore, the scroll compressor of Patent Document 1 tends to have a long overall length of the orbiting scroll in the axial direction of the rotation shaft, resulting in significant thermal expansion due to temperature rise during operation. Because the scroll compressor of Patent Document 1 experiences significant thermal expansion due to temperature rise during operation, if the tip clearance between the tip of the orbiting scroll's orbiting scroll and the fixed base plate of the fixed scroll is narrow, the tip of the orbiting scroll may come into contact with the fixed base plate of the fixed scroll with a strong load. Therefore, the scroll compressor of Patent Document 1 requires a large tip clearance, which can easily lead to refrigerant leakage from the compression chamber.

[0005] The present disclosure is intended to solve the above-mentioned problems, and aims to provide a scroll compressor that has two compression chambers and is capable of suppressing refrigerant leakage from each compression chamber.

[0006] A scroll compressor according to the present disclosure includes a compression mechanism that compresses a refrigerant and a rotating shaft that drives the compression mechanism, the compression mechanism including a first compression section through which the rotating shaft passes, a second compression section through which the rotating shaft passes and arranged in line with the first compression section in the axial direction of the rotating shaft, and a thrust plate arranged axially between the first compression section and the second compression section, the first compression section including a first fixed scroll having a first fixed base plate and a first fixed spiral formed on one surface of the first fixed base plate, a first oscillating base plate and a first fixed spiral formed on one surface of the first oscillating base plate The second compression section comprises a first oscillating scroll having a first oscillating spiral that meshes with the fixed spiral to form a first compression chamber, and a second fixed scroll having a second fixed base plate and a second fixed spiral formed on one surface of the second fixed base plate, and a second oscillating scroll having a second oscillating base plate and a second oscillating spiral formed on one surface of the second oscillating base plate and that meshes with the second fixed spiral to form a second compression chamber, and the other surface of the first oscillating base plate, which is the back surface, and the other surface of the second oscillating base plate, which is the back surface, are arranged opposite each other with a thrust plate sandwiched between them.

[0007] In the scroll compressor of the present disclosure, the first compression section and the second compression section each have an orbiting scroll, and the first compression chamber and the second compression chamber are formed without sharing a wobbler base plate. As a result, the scroll compressor can shorten the overall axial length per orbiting scroll compared to a scroll compressor in which an orbiting spiral is formed on both sides of the orbiting scroll, suppress thermal expansion, reduce the tip clearance, and suppress refrigerant leakage from the first compression chamber and the second compression chamber.

[0008] 1 is a schematic longitudinal sectional view of the overall configuration of a scroll compressor according to embodiment 1. FIG. 2 is a schematic longitudinal sectional view of a compression mechanism of the scroll compressor according to embodiment 1. FIG. 3 is a horizontal sectional view of a first compression section of the scroll compressor according to embodiment 1. FIG. 4 is a horizontal sectional view of a second compression section of the scroll compressor according to embodiment 1. FIG. 5 is a diagram showing the flow of refrigerant in the scroll compressor according to embodiment 1. FIG. 6 is a diagram showing the flow of refrigeration oil in the scroll compressor according to embodiment 1. FIG. 7 is a schematic longitudinal sectional view of a compression mechanism of a scroll compressor according to embodiment 2. FIG. 8 is an explanatory diagram of pressure acting on a first oscillating base plate in the first compression section of the scroll compressor according to embodiment 2. FIG. 9 is a schematic longitudinal sectional view of a compression mechanism of a scroll compressor according to embodiment 3. FIG. 10 is a schematic longitudinal sectional view showing an internal flow path in a thrust plate of a scroll compressor according to embodiment 4. FIG. 11 is a perspective view of a flow path component of a scroll compressor according to embodiment 4.

[0009] Hereinafter, a scroll compressor according to an embodiment will be described with reference to the drawings. In the following drawings, including FIG. 1, components with the same reference numerals are the same or equivalent, and are common throughout the embodiments described below. The configurations of the components shown throughout the specification are merely examples, and the present invention is not limited to the configurations described in the specification.

[0010] Embodiment 1 Fig. 1 is a schematic vertical cross-sectional view of the overall configuration of a scroll compressor 1000 according to Embodiment 1. Fig. 2 is a schematic vertical cross-sectional view of a compression mechanism 8 of the scroll compressor 1000 according to Embodiment 1. Fig. 3 is a horizontal cross-sectional view of a first compression section 8A of the scroll compressor 1000 according to Embodiment 1. Fig. 4 is a horizontal cross-sectional view of a second compression section 8B of the scroll compressor 1000 according to Embodiment 1.

[0011] The scroll compressor 1000 of the first embodiment has a compression mechanism 8, an electric mechanism 200, a rotating shaft 7 that connects the compression mechanism 8 and the electric mechanism 200 and transmits the rotational force of the electric mechanism 200 to the compression mechanism 8, and other components. The scroll compressor 1000 has a configuration in which the compression mechanism 8, the electric mechanism 200, the rotating shaft 7, and other components are housed inside a sealed container 100 that forms an outer shell. Within the sealed container 100, the compression mechanism 8 is disposed below, and the electric mechanism 200 is disposed above the compression mechanism 8. In the following description, the direction in which the rotating shaft 7 extends is referred to as the axial direction, and the direction perpendicular to the axial direction is referred to as the radial direction.

[0012] The scroll compressor 1000 in FIG. 1 is an example of a so-called vertical scroll compressor that is used with its axial direction aligned with the direction of gravity. However, the scroll compressor may be a horizontal scroll compressor that is arranged so that its axial direction is inclined or horizontal with respect to the direction of gravity.

[0013] The scroll compressor 1000 is applied to refrigeration cycle devices such as air conditioners and refrigerators, and is connected by refrigerant piping to a heat exchanger that functions as a condenser or an evaporator and an expansion device, and has the function of compressing the refrigerant to produce a high-temperature, high-pressure gas refrigerant.

[0014] The sealed container 100 is provided with suction pipes 101 and 102 for drawing in a refrigerant, and a discharge pipe 103 for discharging the refrigerant. The suction pipes 101 and 102 are branched into two systems upstream via a suction muffler (not shown).

[0015] Here, the space inside the sealed container 100 is defined as follows: Within the internal space of the sealed container 100, the space above the electric mechanism 200 is referred to as a first space 80. The space surrounded by the electric mechanism 200 and the compression mechanism 8 is referred to as a second space 81. The space below the compression mechanism 8 is referred to as an oil reservoir space 82 in which refrigerating machine oil 300 is stored.

[0016] The electric mechanism 200 supplies rotational driving force to the rotating shaft 7 and includes a rotor 201 and a stator 202. The stator 202 is fixed to the sealed container 100 by shrink fitting or the like. The stator 202 is connected to a glass terminal 104 installed in the sealed container 100 by a lead wire 104a in order to obtain electric power from the outside. The rotor 201 is fixed to the rotating shaft 7 by shrink fitting or the like. The rotor 201 is driven to rotate when current is applied to the stator 202, and has the function of rotating the rotating shaft 7. A first balance weight 16 and a second balance weight 17 are fixed above and below the rotor 201 to balance the entire rotating system of the scroll compressor 1000.

[0017] A vent hole 200A is formed in the rotor 201, penetrating it in the axial direction. The vent hole 200A serves to guide the refrigerant compressed and discharged by the compression mechanism 8 to the first space 80 at the top of the sealed container 100, and also to allow the refrigeration oil 300 guided to the first space 80 to fall to the bottom of the sealed container 100. In addition, a communication flow path 84 is formed between the outer circumferential surface of the stator 202 and the sealed container 100, connecting the first space 80 and the second space 81 and serving as a flow path for the refrigerant and the refrigeration oil 300.

[0018] Compression mechanism 8 has a function of compressing refrigerant drawn from suction pipes 101 and 102 from low pressure to high pressure and discharging the compressed refrigerant into first space 80, which is a high-pressure space within sealed container 100. Compression mechanism 8 has a first compression section 8A having a first compression chamber 30, a second compression section 8B having a second compression chamber 31, and a thrust plate 5. First compression section 8A and second compression section 8B are arranged side by side in the axial direction, and thrust plate 5 is arranged between first compression section 8A and second compression section 8B in the axial direction. Compression mechanism 8 is configured with first compression section 8A, thrust plate 5, and second compression section 8B arranged side by side in this order in the axial direction.

[0019] The first compression section 8A includes a first fixed scroll 1 and a first orbiting scroll 2. The second compression section 8B includes a second fixed scroll 3 and a second orbiting scroll 4. The compression mechanism 8 has a configuration in which the first fixed scroll 1, the first orbiting scroll 2, the thrust plate 5, the second orbiting scroll 4, and the second fixed scroll 3 are arranged in this order in the axial direction.

[0020] The first fixed scroll 1 is fixed to the sealed casing 100 by a method such as shrink fitting or welding. The second fixed scroll 3 is fixed to the first fixed scroll 1 with bolts via a thrust plate 5. In other words, the second fixed scroll 3 and the thrust plate 5 are fixed to the first fixed scroll 1 which is fixed to the sealed casing 100 with bolts. Note that although the first fixed scroll 1 is fixed to the sealed casing 100 here, the second fixed scroll 3 may be fixed to the sealed casing 100, and the first fixed scroll 1 may be fixed to the second fixed scroll 3 with bolts via the thrust plate 5.

[0021] The thrust plate 5 is divided into two in the axial direction, namely, thrust plate 5A and thrust plate 5B. Note that the thrust plate 5 may be integrally formed without being divided into thrust plate 5A and thrust plate 5B.

[0022] A communicating passage 83 extending in the axial direction is formed between the compression mechanism 8 and the inner peripheral surface of the sealed container 100. The communicating passage 83 is formed by axially communicating grooves or notches formed in the same phase on the outer peripheral surfaces of the first fixed scroll 1, the second fixed scroll 3, and the thrust plate 5. The communicating passage 83 serves to guide the refrigerant gas discharged from the second compression section 8B to the second space 81, and to drop the refrigerating machine oil 300 guided to the second space 81 together with the refrigerant gas into the oil reservoir space 82.

[0023] The rotating shaft 7 drives the compression mechanism 8 by transmitting the rotational force of the electric mechanism 200 to the compression mechanism 8. The rotating shaft 7 is disposed so as to pass through shaft holes provided in the centers of the first fixed scroll 1, the first orbiting scroll 2, the thrust plate 5, the second orbiting scroll 4, and the second fixed scroll 3. The rotating shaft 7 has a first shaft portion 7A at an upper portion, a second shaft portion 7B at a lower portion, and an eccentric shaft portion 7C at an intermediate portion. The eccentric shaft portion 7C is eccentric with respect to the axis of the rotating shaft 7. The axis of the rotating shaft 7 coincides with the axis of the first shaft portion 7A and the second shaft portion 7B. The eccentric shaft portion 7C is divided into two in the axial direction, and has a first eccentric shaft portion 7C1 and a second eccentric shaft portion 7C2. The first eccentric shaft portion 7C1 and the second eccentric shaft portion 7C2 are disposed in opposite phases, i.e., have a phase difference of π.

[0024] The first shaft portion 7A is fitted into a bearing 1A arranged in the shaft hole of the first fixed scroll 1. The bearing 1A is fixed by, for example, press-fitting a bearing material used in plain bearings, such as a copper-lead alloy, into the inner periphery of the shaft hole of the first fixed scroll 1. The second shaft portion 7B is fitted into a bearing 3A arranged in the shaft hole of the second fixed scroll 3. The bearing 3A is fixed by, for example, press-fitting a bearing material used in plain bearings, such as a copper-lead alloy, into the inner periphery of the shaft hole of the second fixed scroll 3. The first shaft portion 7A and the second shaft portion 7B slide against each other via an oil film of refrigerating machine oil 300.

[0025] As shown in Fig. 3 , the first eccentric shaft portion 7C1 is fitted into a bearing 2A arranged in the axial hole of the first orbiting scroll 2, and drives the first orbiting scroll 2 by rotation of the rotary shaft 7. The bearing 2A is fixed to the inner periphery of the axial hole of the first orbiting scroll 2 by press-fitting a bearing material used in plain bearings, such as a copper-lead alloy. As shown in Fig. 4 , the second eccentric shaft portion 7C2 is fitted into a bearing 4A arranged in the axial hole of the second orbiting scroll 4, and drives the second orbiting scroll 4 by rotation of the rotary shaft 7. The bearing 4A is fixed to the inner periphery of the axial hole of the second orbiting scroll 4 by press-fitting a bearing material used in plain bearings, such as a copper-lead alloy.

[0026] The shaft hole 6 provided in the center of the thrust plate 5 is configured with a hole diameter that prevents sliding with the outer peripheral surface of the rotating shaft 7, and no bearing is placed in the shaft hole 6 of the thrust plate 5.

[0027] The rotating shaft 7 is supported by a bearing 1A arranged on the first fixed scroll 1 and a bearing 3A arranged on the second fixed scroll 3, and transmits driving force to a bearing 2A arranged on the first orbiting scroll 2 and a bearing 4A arranged on the second orbiting scroll 4. An eccentric shaft portion 7C of the rotating shaft 7 is fitted into the first orbiting scroll 2 via the bearing 2A and into the second orbiting scroll 4 via the bearing 4A, and rotation of the rotating shaft 7 causes the first orbiting scroll 2 and the second orbiting scroll 4 to orbit.

[0028] The rotating shaft 7 has an oil supply hole 71 that supplies refrigeration oil 300 stored in the oil reservoir space 82 to the compression mechanism 8. The oil supply hole 71 has an axial hole 71a that extends axially through the center of the rotating shaft 7, and a plurality of radial holes 71b that communicate with the axial hole 71a and extend radially. The radial holes 71b are formed in positions facing the bearing 4A, the bearing 3A, the bearing 2A, and the bearing 1A, respectively. In addition, the radial holes 71b are also formed in positions that communicate with the axial hole 6 of the thrust plate 5.

[0029] A stirrer 72, which is a twist plate, is provided in the axial hole 71a, and refrigerating machine oil 300 stored in the oil reservoir space 82 rises through the axial hole 71a of the oil feed hole 71 due to the pressure-feeding action of the stirrer 72 caused by the rotation of the rotating shaft 7, and is supplied to each bearing through the multiple radial holes 71b. Because the compression mechanism 8 is provided below the electric mechanism 200, it is close to the oil reservoir space 82, making it easy to supply refrigerating machine oil 300 to the compression mechanism 8 and Oldham rings 10 and 11, which will be described later. The refrigerating machine oil 300 supplied to the compression mechanism 8, Oldham ring 10, and Oldham ring 11 is returned to the oil reservoir space 82. In addition, a rotating plate 70 that separates the refrigerant and refrigerating machine oil 300 is provided at the upper end of the rotating shaft 7.

[0030] Next, the compression mechanism 8, which is a characteristic part, will be described in detail with reference to FIGS.

[0031] (First compression section 8A) As described above, the first compression section 8A has the first fixed scroll 1 and the first orbiting scroll 2. The first fixed scroll 1 has a first fixed base plate 1a and a first fixed spiral 1b which is a spiral protrusion formed on one surface of the first fixed base plate 1a. The first orbiting scroll 2 has a first orbiting base plate 2a and a first orbiting spiral 2b which is a spiral protrusion formed on one surface of the first orbiting base plate 2a.

[0032] Between the first fixed scroll 1b and the first oscillating scroll 2b, a plurality of first compression chambers 30 are formed. The volumes of the first compression chambers 30 decrease radially inward as the rotary shaft 7 rotates. The first compression chambers 30 communicate with a suction pipe 101 that penetrates the sealed container 100 and the first fixed scroll 1, and compress the refrigerant drawn through the suction pipe 101. As shown in FIG. 3 , the first fixed scroll 1b has a shape that is elongated toward the end of its winding relative to the first oscillating scroll 2b, and the first fixed scroll 1b and the first oscillating scroll 2b are asymmetric. The first fixed scroll 1b and the first oscillating scroll 2b are not limited to being asymmetrical, and may be symmetrical. When the first fixed scroll 1b and the first oscillating scroll 2b are symmetrical, they are arranged in the sealed container 100 in a point-symmetrical manner, meshing in opposite phases.

[0033] Tip seals (not shown) made of resin or metal may be provided at the tips of the first fixed volute 1 b and the first oscillating volute 2 b to fill gaps between the tips of the volute teeth and prevent refrigerant from leaking from the first compression chamber 30.

[0034] A first rotation prevention mechanism is disposed between the first orbiting scroll 2 and the thrust plate 5A to prevent the first orbiting scroll 2 from rotating relative to the first fixed scroll 1. The first rotation prevention mechanism is an Oldham ring 10. The Oldham ring 10 connects the first orbiting scroll 2 and the thrust plate 5A so that they can freely swing. A pair of Oldham keyways 2B is formed on the other surface of the first orbiting base plate 2a, in other words, on a back surface 20 opposite the surface on which the first orbiting spiral 2b is formed. A pair of Oldham keyways 5A1 is formed on the surface of the thrust plate 5A facing the first orbiting base plate 2a.

[0035] The Oldham ring 10 has an annular portion and key portions. A pair of key portions is provided on the upper and lower surfaces of the annular portion. The pair of key portions provided on the upper surface of the annular portion are arranged so that the line connecting them is perpendicular to the line connecting the pair of key portions provided on the lower surface of the annular portion. The pair of key portions provided on the upper surface of the annular portion are inserted into a pair of Oldham key grooves 2B of the first oscillating base plate 2a. The pair of key portions provided on the lower surface of the annular portion are inserted into a pair of Oldham key grooves 5A1 of the thrust plate 5A. The first orbiting scroll 2 is prevented from rotating by the Oldham ring 10 and performs an orbital motion. Note that the first anti-rotation mechanism in the first compression section 8A is not limited to an Oldham ring and may be a so-called pin-hole type.

[0036] A discharge port 1B is formed in the first fixed base plate 1a, through which the refrigerant compressed in the first compression chamber 30 and brought to a high pressure is discharged. A reed valve 12 that prevents backflow of the compressed refrigerant and a valve retainer 13 that regulates the opening and closing of the reed valve 12 are attached to the first fixed base plate 1a downstream of the discharge port 1B. The volume of the first compression chamber 30 decreases as the rotary shaft 7 rotates, and the pressure increases. When the pressure reaches the discharge pressure, the refrigerant in the first compression chamber 30 is discharged from the discharge port 1B. A discharge muffler 18 is attached to the back surface of the first fixed base plate 1a, opposite the surface on which the first fixed volute 1b is formed, so as to cover the discharge port 1B. A discharge hole 18A is formed in the discharge muffler 18, and the refrigerant in the discharge muffler 18 is discharged into the second space 81 through the discharge hole 18A.

[0037] (Second compression section 8B) As described above, the second compression section 8B has the second fixed scroll 3 and the second orbiting scroll 4. The second fixed scroll 3 has a second fixed base plate 3a and a second fixed spiral 3b which is a spiral protrusion formed on one surface of the second fixed base plate 3a. The second orbiting scroll 4 has a second oscillating base plate 4a and a second orbiting spiral 4b which is a spiral protrusion formed on one surface of the second oscillating base plate 4a.

[0038] Between the second fixed scroll 3b and the second oscillating scroll 4b, a plurality of second compression chambers 31 are formed. The volume of the second compression chambers 31 decreases radially inward as the rotary shaft 7 rotates. The second compression chambers 31 communicate with a suction pipe 102 that penetrates the sealed container 100 and the second fixed scroll 3, and compresses the refrigerant drawn through the suction pipe 102. As shown in FIG. 4 , the second fixed scroll 3b has a shape that is more elongated at the end of its spiral than the second oscillating scroll 4b, and the second fixed scroll 3b and the second oscillating scroll 4b are asymmetric. The second fixed scroll 3b and the second oscillating scroll 4b are not limited to being asymmetrical, and may be symmetrical. When the second fixed scroll 3b and the second oscillating scroll 4b are symmetrical, they are arranged in the sealed container 100 in a point-symmetrical manner, meshing in opposite phases.

[0039] Tip seals (not shown) made of resin or metal may be provided at the tips of the second fixed volute 3 b and the second oscillating volute 4 b to fill gaps between the tips of the volute teeth and prevent refrigerant from leaking from the second compression chamber 31.

[0040] A second rotation prevention mechanism is disposed between the second orbiting scroll 4 and the thrust plate 5B to prevent the second orbiting scroll 4 from rotating relative to the second fixed scroll 3. The second rotation prevention mechanism is an Oldham ring 11. The Oldham ring 11 connects the second orbiting scroll 4 and the thrust plate 5B so that they can freely swing. A pair of Oldham keyways 4B is formed on the other surface of the second orbiting base plate 4a, in other words, on the back surface 40 opposite the surface on which the second orbiting spiral 4b is formed. A pair of Oldham keyways 5B1 is formed on the surface of the thrust plate 5B facing the second orbiting base plate 4a.

[0041] The Oldham ring 11 has an annular portion and key portions. A pair of key portions is provided on the upper and lower surfaces of the annular portion. The pair of key portions provided on the upper surface of the annular portion are arranged so that the line connecting them is perpendicular to the line connecting the pair of key portions provided on the lower surface of the annular portion. The pair of key portions provided on the upper surface of the annular portion are inserted into a pair of Oldham key grooves 5B1 of the thrust plate 5B. The pair of key portions provided on the lower surface of the annular portion are inserted into a pair of Oldham key grooves 4B of the second oscillating base plate 4a. The second oscillating scroll 4 is prevented from rotating by the Oldham ring 11 and performs an orbital motion. Note that the second anti-rotation mechanism in the second compression section 8B is not limited to an Oldham ring and may be a so-called pin-hole type.

[0042] A discharge port 3B is formed in the second fixed base plate 3a, which discharges the refrigerant compressed in the second compression chamber 31 and brought to a high pressure. A reed valve 14 that prevents backflow of the compressed refrigerant and a valve retainer 15 that regulates the opening and closing of the reed valve 14 are attached to the second fixed base plate 3a downstream of the discharge port 3B. The volume of the second compression chamber 31 decreases and the pressure increases as the rotary shaft 7 rotates. When the pressure reaches the discharge pressure, the refrigerant in the second compression chamber 31 is discharged from the discharge port 3B. A discharge muffler 19 is attached to the back surface of the second fixed base plate 3a, opposite the surface on which the second fixed volute 3b is formed, so as to cover the discharge port 3B.

[0043] The compression mechanism 8 is arranged in a sealed container 100 with the first orbiting scroll 2 of the first compression section 8A and the second orbiting scroll 4 of the second compression section 8B facing each other with a thrust plate 5 sandwiched between them, with the back surfaces 20 and 40 facing each other. The compression mechanism 8 is arranged so that the first orbiting spiral 2b of the first orbiting scroll 2 and the first fixed spiral 1b of the first fixed scroll 1 mesh with each other to form a first compression chamber 30. The compression mechanism 8 is arranged so that the second orbiting spiral 4b of the second orbiting scroll 4 and the second fixed spiral 3b of the second fixed scroll 3 mesh with each other to form a second compression chamber 31. The compression mechanism 8 connects the first compression chamber 30 and the second compression chamber 31 in parallel in the refrigerant flow, and after sucking in and compressing the refrigerant separately into each of the first compression chamber 30 and the second compression chamber 31, the compressed refrigerant is discharged from each of the first compression chamber 30 and the second compression chamber 31 into the internal space of the sealed container 100.

[0044] (Thrust Plate 5) The thrust plate 5 is formed with a first internal flow path 5A2 that guides the refrigeration oil 300 accumulated in the internal space 6a of the axial hole 6 to the first compression section 8A, and a second internal flow path 5B2 that guides the refrigeration oil 300 accumulated in the internal space 6a of the axial hole 6 to the second compression section 8B. The first internal flow path 5A2 is configured as a hole having one end that opens to the inner circumferential surface of the axial hole 6 of the thrust plate 5 and the other end that opens to the surface of the thrust plate 5 that faces the first oscillating bedplate 2a. The second internal flow path 5B2 is configured as a hole having one end that opens to the inner circumferential surface of the axial hole 6 of the thrust plate 5 and the other end that opens to the surface of the thrust plate 5 that faces the second oscillating bedplate 4a. The first internal flow path 5A2 and the second internal flow path 5B2 are configured as a straight radial flow path extending in the radial direction and a straight axial flow path extending in the axial direction.

[0045] In the scroll compressor 1000, in order to minimize refrigerant leakage in the compression mechanism 8 and ensure stable operation, the following alignment is required between each of the first fixed scroll 1 and the second fixed scroll 3 and the thrust plate 5. In the scroll compressor 1000, the centers of the first fixed scroll 1 and the second fixed scroll 3 and the thrust plate 5 must be aligned and their rotational phases must be matched. For this reason, it is desirable to align the positions of each of the first fixed scroll 1 and the second fixed scroll 3 and the thrust plate 5 using highly accurate pin holes and pins (not shown). Furthermore, the axes of the first fixed scroll 1 and the second fixed scroll 3 must be aligned from the standpoint of bearing reliability.

[0046] Here, the thrust plate 5 is divided into thrust plate 5A and thrust plate 5B and configured as separate bodies. This makes it easy to perform the above-described alignment during manufacturing of the scroll compressor 1000. From the standpoint of the above-described alignment, it is preferable that the thrust plate 5 is divided into thrust plate 5A and thrust plate 5B and configured as separate bodies. However, the thrust plate 5 may also be configured as a single plate in which the thrust plates 5A and 5B are integrated.

[0047] Next, the flow of refrigerant will be described. Figure 5 is a diagram showing the flow of refrigerant in the scroll compressor 1000 according to the first embodiment. Arrows in Figure 5 indicate the flow of refrigerant. As the electric mechanism 200 is driven, refrigerant flows from an external refrigeration cycle into the compression mechanism 8 in the sealed container 100 via the suction pipes 101 and 102. The low-pressure refrigerant drawn into the first compression section 8A via the suction pipe 101 flows into the first compression chamber 30, where it is pressurized from low to high, and then discharged from the discharge port 1B into the internal space of the discharge muffler 18. The low-pressure refrigerant drawn into the second compression section 8B via the suction pipe 102 flows into the second compression chamber 31, where it is pressurized from low to high, and then discharged from the discharge port 3B into the internal space of the discharge muffler 19.

[0048] The refrigerant discharged from discharge port 3B into the internal space of discharge muffler 19 flows into the internal space of discharge muffler 18 through a communication passage 83 formed between compression mechanism 8 and the inner circumferential surface of sealed container 100. The refrigerant that flows into the internal space of discharge muffler 18 through communication passage 83 mixes with the refrigerant that has been discharged from discharge port 1B and flowed into the internal space of discharge muffler 18, and is then discharged from discharge hole 18A into second space 81. The refrigerant discharged into second space 81 passes through air holes 200A formed in rotor 201, passes through first space 80, and is discharged from discharge pipe 103 to the outside of the compressor.

[0049] Next, the flow of refrigeration oil 300 will be described. Figure 6 is a diagram showing the flow of refrigeration oil 300 in scroll compressor 1000 according to embodiment 1. Arrows in Figure 6 indicate the flow of refrigeration oil 300. Refrigeration oil 300 stored in oil reservoir space 82 is supplied to each bearing via oil supply hole 71 of rotating shaft 7. More specifically, refrigeration oil 300 rises up axial hole 71a of rotating shaft 7 due to rotation of stirrer 72 inserted in axial hole 71a, and centrifugal force is applied to the refrigeration oil 300, which is then supplied to each bearing from each radial hole 71b.

[0050] The radial holes 71b include a radial hole 71b1 formed in a position facing bearing 1A, a radial hole 71b2 formed in a position facing bearing 2A, a radial hole 71b3 formed in a position facing bearing 3A, and a radial hole 71b4 formed in a position facing bearing 4A. The radial holes 71b also include a radial hole 71b5 formed in a position communicating with the shaft hole 6 of the thrust plate 5.

[0051] Refrigerating machine oil 300 passes through radial hole 71b3, radial hole 71b4, radial hole 71b2, and radial hole 71b1, and is supplied to bearing 3A, bearing 4A, bearing 2A, and bearing 1A. Refrigerating machine oil 300 is also supplied to internal space 6a of shaft hole 6 from radial hole 71b5.

[0052] The refrigeration oil 300 supplied to bearing 3A is returned to the oil reservoir space 82 through the gap between bearing 3A and the rotating shaft 7. The refrigeration oil 300 supplied to bearing 1A flows into the second space 81 through the gap between bearing 1A and the rotating shaft 7. The refrigeration oil 300 supplied to bearing 2A and bearing 4A and the refrigeration oil 300 supplied to the internal space 6a of the shaft hole 6 are supplied to the first compression section 8A through a first internal flow path 5A2 formed in the thrust plate 5, and are supplied to the second compression section 8B through a second internal flow path 5B2.

[0053] The refrigeration oil 300 supplied to the first compression section 8A via the first internal flow path 5A2 flows into the suction space of the first compression section 8A. A portion of the refrigeration oil 300 that flows into the suction space of the first compression section 8A is supplied to the first compression chamber 30. In addition, a portion of the refrigeration oil 300 that flows into the suction space of the first compression section 8A is supplied to the Oldham ring 10. The refrigeration oil 300 supplied to the first compression chamber 30 mixes with the refrigerant to be compressed and is discharged from the discharge port 1B into the internal space of the discharge muffler 18 in the same manner as the refrigerant flow described above.

[0054] The refrigeration oil 300 supplied to the second compression section 8B via the second internal flow path 5B2 flows into the suction space of the second compression section 8B. A portion of the refrigeration oil 300 that has flowed into the suction space of the second compression section 8B is supplied to the second compression section 8B. In addition, a portion of the refrigeration oil 300 that has flowed into the suction space of the second compression section 8B is supplied to the Oldham ring 11.

[0055] The refrigeration oil 300 supplied to the second compression chamber 31 mixes with the refrigerant to be compressed, is discharged from the discharge port 3B into the internal space of the discharge muffler 19 in the same manner as the refrigerant flow described above, and flows into the internal space of the discharge muffler 18 through the communication flow path 83. The refrigeration oil 300 that flows into the internal space of the discharge muffler 18 through the communication flow path 83 mixes with the refrigeration oil 300 discharged from the discharge port 1B into the internal space of the discharge muffler 18, and is then discharged from the discharge hole 18A of the discharge muffler 18 into the second space 81. The refrigeration oil 300 discharged into the second space 81 flows into the first space 80 through the air holes 200A of the rotor 201 together with the refrigeration oil 300 that has flowed into the second space 81 via the bearing 1A.

[0056] The refrigeration oil 300 that has flowed into the first space 80 collides with the rotating plate 70 installed on the rotating shaft 7, is separated from the refrigerant due to the difference in density between the refrigerant and the refrigeration oil 300, and flows radially outward along the underside of the rotating plate 70. The refrigeration oil 300 that has flowed radially outward along the underside of the rotating plate 70 is blown from the rotating plate 70 toward the inner circumferential surface of the sealed container 100, adheres to the inner circumferential surface of the sealed container 100, and flows near the wall surface of the second space 81 through a communicating flow path 84 formed on the outer periphery of the stator 202. The refrigeration oil 300 that has flowed near the wall surface of the second space 81 passes through a communicating flow path 83 formed on the outer periphery of the compression mechanism 8 and is returned to the oil reservoir space 82.

[0057] In conventional scroll compressors, the orbiting scroll has an orbiting scroll formed on both sides of the orbiting base plate, and the two compression sections share the orbiting base plate. This increases the overall axial length of the orbiting scroll, which increases thermal expansion due to temperature rise during operation. This necessitates a large tip clearance, which can easily lead to refrigerant leakage.

[0058] In contrast, in the scroll compressor 1000 of the first embodiment, the oscillating base plates are independent in the two compression sections, the first compression section 8A and the second compression section 8B. The scroll compressor 1000 has a configuration in which the back surface 20 of the first oscillating base plate 2a and the back surface 40 of the second oscillating base plate 4a are arranged opposite each other with the thrust plate 5 sandwiched therebetween, and the first compression chamber 30 and the second compression chamber 31 are formed without sharing the oscillating base plate.

[0059] With the above configuration, the scroll compressor 1000 can shorten the overall axial length per orbiting scroll compared to a conventional configuration in which two compression sections share a swing base plate and have the same compression ratio. By shortening the overall axial length per orbiting scroll, the scroll compressor 1000 can suppress thermal expansion and reduce tip clearances, thereby suppressing refrigerant leakage from the compression chambers. In other words, the scroll compressor 1000 can shorten the overall axial lengths of the first orbiting scroll 2 and the second orbiting scroll 4, thereby suppressing refrigerant leakage from the first compression chamber 30 and the second compression chamber 31.

[0060] The first orbiting scroll 2 is fitted to the first eccentric shaft portion 7C1, and the second orbiting scroll 4 is fitted to the second eccentric shaft portion 7C2. The first eccentric shaft portion 7C1 and the second eccentric shaft portion 7C2 are arranged to have a phase difference of π, as described above. Therefore, the scroll compressor 1000 can cancel out the horizontal gas load acting on the first orbiting scroll 2 in the first compression section 8A and the horizontal gas load acting on the second orbiting scroll 4 in the second compression section 8B. Therefore, the scroll compressor 1000 can reduce axial deflection and improve reliability. The horizontal gas load is a load acting horizontally on the orbiting scroll due to the pressure difference between the suction pressure and the discharge pressure.

[0061] Furthermore, conventional scroll compressors have a cantilever bearing structure in which the rotating shaft passes through one of the two fixed scrolls and is supported by a bearing disposed on that fixed scroll. As a result, conventional scroll compressors have the problem of uneven contact with the bearing due to tilting of the rotating shaft, which leads to increased bearing loss and burnout.

[0062] In contrast, the scroll compressor 1000 of the first embodiment has a double-supported bearing structure in which the rotating shaft 7 passes through both the first fixed scroll 1 and the second fixed scroll 3 and is supported by bearings arranged in each of the first fixed scroll 1 and the second fixed scroll 3. The double-supported bearing structure of the scroll compressor 1000 makes it possible to suppress the above-mentioned problems that occur with a cantilevered bearing structure, resulting in improved compressor performance and reduced power consumption.

[0063] The scroll compressor 1000 has a simple structure and can be easily manufactured because the orbiting scroll and the fixed scroll are configured such that the spirals are formed on only one side of the base plate as described above.

[0064] A conventional scroll compressor having two compression sections has a configuration in which a spiral is formed on both sides of a base plate of a fixed scroll, and two orbiting scrolls are arranged to mesh with the spiral (for example, Japanese Patent Laid-Open Publication No. 4-101089). In this scroll compressor, the fixed scroll is shared by the two compression sections, so the length of the discharge port provided inside the fixed scroll tends to be long, which increases discharge pressure loss and increases the input power of the compressor.

[0065] In contrast, the scroll compressor 1000 has a configuration in which the first fixed scroll 1 and the second fixed scroll 3 are separate bodies, each having a discharge port. Therefore, the length of the discharge port can be made shorter than in the conventional scroll compressor, and an increase in discharge pressure loss can be suppressed.

[0066] As described above, the scroll compressor 1000 of the first embodiment includes the compression mechanism 8 that compresses a refrigerant and the rotating shaft 7 that drives the compression mechanism 8. The compression mechanism 8 includes a first compression section 8A through which the rotating shaft 7 passes, and a second compression section 8B through which the rotating shaft 7 passes and which is arranged alongside the first compression section 8A in the axial direction of the rotating shaft 7. The compression mechanism 8 includes a thrust plate 5 that is arranged axially between the first compression section 8A and the second compression section 8B. The first compression section 8A includes a first fixed scroll 1 and a first orbiting scroll 2. The first fixed scroll 1 has a first fixed base plate 1a and a first fixed spiral 1b formed on one surface of the first fixed base plate 1a. The first orbiting scroll 2 has a first oscillating base plate 2a and a first oscillating spiral 2b formed on one surface of the first oscillating base plate 2a and meshing with the first fixed spiral 1b to form a first compression chamber 30. The second compression unit 8B includes a second fixed scroll 3 and a second orbiting scroll 4. The second fixed scroll 3 has a second fixed base plate 3a and a second fixed spiral 3b formed on one surface of the second fixed base plate 3a. The second orbiting scroll 4 has a second oscillating base plate 4a and a second oscillating spiral 4b formed on one surface of the second oscillating base plate 4a and meshing with the second fixed spiral 3b to form a second compression chamber 31. A back surface 40, which is the other surface of the first oscillating base plate 2a, and a back surface 40, which is the other surface of the second oscillating base plate 4a, are arranged opposite each other with a thrust plate 5 sandwiched therebetween.

[0067] With the above configuration, the scroll compressor 1000 can shorten the overall axial length of each orbiting scroll. By shortening the overall axial length of each orbiting scroll, the scroll compressor 1000 can suppress thermal expansion and therefore reduce tip clearances. By reducing the tip clearances, the scroll compressor 1000 can suppress refrigerant leakage from the compression chambers.

[0068] The rotating shaft 7 has a first eccentric shaft portion 7C1 that drives the first orbiting scroll 2 and a second eccentric shaft portion 7C2 that drives the second orbiting scroll 4. The first eccentric shaft portion 7C1 and the second eccentric shaft portion 7C2 are arranged in opposite phases to each other.

[0069] With the above configuration, the scroll compressor 1000 can offset the horizontal gas load acting on the first orbiting scroll 2 and the horizontal gas load acting on the second orbiting scroll 4, thereby reducing axial deflection and improving reliability.

[0070] The thrust plate 5 is divided into two parts in the axial direction.

[0071] With the above-described configuration, the scroll compressor 1000 makes it easy to align the first fixed scroll 1, the second fixed scroll 3, and the thrust plate 5 during manufacturing.

[0072] The first compression section 8A swingably connects the first orbiting scroll 2 and the thrust plate 5, and has a first rotation prevention mechanism that prevents rotation of the first orbiting scroll 2. The second compression section 8B swingably connects the second orbiting scroll 4 and the thrust plate 5, and has a second rotation prevention mechanism that prevents rotation of the second orbiting scroll 4.

[0073] With the above-described configuration, the scroll compressor 1000 can prevent the first orbiting scroll 2 and the second orbiting scroll 4 from rotating on their axes.

[0074] 7 is a schematic vertical cross-sectional view of a compression mechanism 8 of a scroll compressor 1000 according to a second embodiment. In the second embodiment, only the structure different from that of the first embodiment will be described. In the second embodiment, the structure of the first orbiting scroll 2 and the second orbiting scroll 4 differs from that of the first embodiment.

[0075] Two concentric first annular grooves, a first annular groove 21a and a first annular groove 21b, are formed in the back surface 20 of the first orbiting scroll 2. The first annular groove 21a and the first annular groove 21b are formed concentrically. An annular seal ring 21a1 is inserted into the first annular groove 21a. An annular seal ring 21b1 is inserted into the first annular groove 21b. The seal rings 21a1 and 21b1 are preferably made of a resin or metal material with good sliding properties.

[0076] As shown in Figure 7, an annular first back pressure chamber 61 is formed between the back surface 20 of the first oscillating plate 2a and the thrust plate 5. The first back pressure chamber 61 is airtightly separated from the surrounding space by seal rings 21a1 and 21b1. The first back pressure chamber 61 is configured as a recess formed in the back surface 20 of the first oscillating plate 2a. The first back pressure chamber 61 communicates with the first compression chamber 30 via a first bleed hole 22 provided in the first oscillating plate 2a. An opening on one end of the first bleed hole 22 communicates with the first compression chamber 30, and an opening 22a on the other end of the first bleed hole 22 is located in an annular portion 20b (see Figure 8 described below) between the first annular grooves 21a and 21b on the back surface 20, and communicates with the first back pressure chamber 61. Through this first bleed hole 22, the intermediate-pressure refrigerant in the first compression chamber 30 is supplied to the first back pressure chamber 61, and an intermediate pressure acts to press the first orbiting scroll 2 against the first fixed scroll 1. The intermediate pressure is a pressure that is higher than the suction pressure and lower than the discharge pressure.

[0077] Two concentric second annular grooves, 41a and 41b, are formed in the back surface 40 of the second orbiting scroll 4. An annular seal ring 41a1 is inserted into the second annular groove 41a. An annular seal ring 41b1 is inserted into the second annular groove 41b. The seal rings 41a1 and 41b1 are preferably made of a resin or metal material with good sliding properties.

[0078] 7 , a partitioned annular second back pressure chamber 62 is formed between the back surface 40 of the second oscillating plate 4a and the thrust plate 5. The second back pressure chamber 62 is airtightly separated from the surrounding space by seal rings 41a1 and 41b1. The second back pressure chamber 62 is configured as a recess formed in the back surface 40 of the second oscillating plate 4a. The second back pressure chamber 62 communicates with the second compression chamber 31 via a second bleed hole 42 provided in the second oscillating plate 4a. One end of the second bleed hole 42 communicates with the second compression chamber 31, and the other end of the second bleed hole 42 is located in an annular portion of the back surface 40 between the second annular grooves 41a and 41b, and communicates with the second back pressure chamber 62. Through this second bleed hole 42 , the intermediate-pressure refrigerant in the second compression chamber 31 is supplied to the second back pressure chamber 62 , and an intermediate pressure acts to press the second orbiting scroll 4 against the second fixed scroll 3 .

[0079] The following describes the operation of the compression mechanism 8 in the scroll compressor 1000 of embodiment 2. Since the operation of the first compression section 8A and the operation of the second compression section 8B are the same, the first compression section 8A will be described as a representative.

[0080] 8 is a diagram illustrating pressures acting on the first oscillating base plate 2a in the first compression section 8A of the scroll compressor 1000 according to Embodiment 2. In Fig. 8, a discharge pressure 400, an intermediate pressure 401, and a suction pressure 402 act on the back surface 20 of the first oscillating base plate 2a.

[0081] The volume of the first compression chamber 30 of the first compression section 8A decreases as the rotary shaft 7 rotates, and the internal pressure increases. The refrigerant being compressed in the first compression chamber 30 is introduced into the first back pressure chamber 61 through the first bleed hole 22. By introducing the refrigerant being compressed into the first back pressure chamber 61, the inside of the first back pressure chamber 61 becomes an intermediate pressure 401, which is a pressure higher than the suction pressure. This intermediate pressure 401 acts on the annular portion 20b between the first annular groove 21a and the first annular groove 21b on the back surface 20 of the first oscillating base plate 2a, as shown in FIG. 8 .

[0082] The internal space 6a of the axial hole 6 of the thrust plate 5 is constantly in communication with the oil reservoir space 82 via the radial hole 71b5 of the rotary shaft 7. The internal space 6a of the axial hole 6 of the thrust plate 5 is the space between the first oscillating bed plate 2a and the thrust plate 5, and is in communication with the space inside the seal ring 21a1. Therefore, the pressure in the space inside the seal ring 21a1 becomes a discharge pressure 400. As shown in FIG. 8 , this discharge pressure 400 acts on the annular portion 20a on the back surface 20 of the first oscillating bed plate 2a, which is inside the first annular groove 21a. Furthermore, a suction pressure 402 acts on the annular portion 20c on the back surface 20 of the first oscillating bed plate 2a, which is outside the first annular groove 21b.

[0083] In this way, the scroll compressor 1000 can apply a load due to the intermediate pressure 401 and a load due to the discharge pressure 400 in addition to the load due to the suction pressure 402 to the rear surface 20 of the first orbiting scroll 2 .

[0084] In the scroll compressor 1000, by appropriately designing the position of the first bleed hole 22, a back pressure load that overcomes the gas load inside the first compression chamber 30 is applied to the back surface 20 of the first orbiting scroll 2, thereby pressing the first orbiting scroll 2 against the first fixed scroll 1. By pressing the first orbiting scroll 2 against the first fixed scroll 1, the scroll compressor 1000 can close the gap between the tip end of the first orbiting scroll 2b and the first fixed base plate 1a. This allows the scroll compressor 1000 to reduce refrigerant leakage from the first compression chamber 30.

[0085] Similarly, in the scroll compressor 1000, by appropriately designing the position of the second bleed hole 42, it is possible to fill the gap between the tip end of the second oscillating volute 4 b and the second fixed base plate 3 a, thereby reducing refrigerant leakage from the second compression chamber 31.

[0086] As described above, the scroll compressor 1000 of the second embodiment not only provides the same effects as those of the first embodiment, but also provides the following effects by having the first back pressure chamber 61 and the second back pressure chamber 62. In the scroll compressor 1000 of the second embodiment, the back pressure introduced into the first back pressure chamber 61 presses the first orbiting scroll 2 against the first fixed scroll 1, and the back pressure introduced into the second back pressure chamber 62 presses the second orbiting scroll 4 against the second fixed scroll 3. As a result, the scroll compressor 1000 of the second embodiment can reduce refrigerant leakage from the first compression chamber 30 and the second compression chamber 31, thereby reducing leakage loss, and can provide a compressor with high capacity and high power consumption reduction effects.

[0087] Note that, when the amount of refrigerant leakage is small and tolerable, or when refrigerant leakage can be suppressed by means other than seal rings, the scroll compressor 1000 does not necessarily have to include seal rings 21a1, 21b1, 41a1, and 41b1. In this case, the first back pressure chamber 61 does not have to be partitioned by seal rings 21a1 and 21b1. In this case, the second back pressure chamber 62 does not have to be partitioned by seal rings 41a1 and 41b1.

[0088] Embodiment 3. Figure 9 is a schematic vertical cross-sectional view of the compression mechanism 8 of a scroll compressor 1000 according to Embodiment 3. In Embodiment 3, only the structure different from Embodiments 1 and 2 will be described. Like Embodiment 2, Embodiment 3 applies loads due to intermediate pressure and discharge pressure to the back surface 20 of the first orbiting scroll 2 and the back surface 40 of the second orbiting scroll 4, respectively, but differs from Embodiment 2 in the position where the annular groove is formed.

[0089] Similar to the scroll compressor 1000 of the second embodiment, the scroll compressor 1000 of the third embodiment has a first annular back pressure chamber 61 airtightly separated from the surrounding space between the back surface 20 of the first oscillating base plate 2a and the thrust plate 5. The first back pressure chamber 61 is formed as a recess formed in the surface of the thrust plate 5A facing the back surface 20 of the first oscillating base plate 2a. Similarly to the scroll compressor 1000 of the second embodiment, the scroll compressor 1000 of the third embodiment has a second annular back pressure chamber 62 airtightly separated from the surrounding space between the back surface 40 of the second oscillating base plate 4a and the thrust plate 5. The second back pressure chamber 62 is formed as a recess formed in the surface of the thrust plate 5B facing the back surface 40 of the second oscillating base plate 4a.

[0090] The scroll compressor 1000 of the third embodiment differs from that of the second embodiment in the positions of the seal rings 21a1, 21b1, 41a1, and 41b1 for airtightly separating the first back pressure chamber 61 and the second back pressure chamber 62 from the surrounding space. The scroll compressor 1000 of the third embodiment has a configuration in which the seal rings 21a1, 21b1, 41a1, and 41b1 are disposed in annular grooves formed in the thrust plate 5.

[0091] More specifically, in the scroll compressor 1000 of the third embodiment, two concentric first annular grooves 5A3 and 5A4 are formed on the surface of the thrust plate 5A facing the first oscillating base plate 2a. The scroll compressor 1000 has a configuration in which a seal ring 21a1 is inserted into the first annular groove 5A3, and a seal ring 21b1 is inserted into the first annular groove 5A4.

[0092] In the scroll compressor 1000 of the third embodiment, two concentric second annular grooves 5B3 and 5B4 are formed on the surface of the thrust plate 5B facing the second oscillating base plate 4a. The scroll compressor 1000 has a configuration in which a seal ring 41a1 is inserted into the second annular groove 5B3, and a seal ring 41b1 is inserted into the second annular groove 5B4.

[0093] The first bleed hole 22 has an opening on one end which communicates with the first compression chamber 30, and an opening 22a on the other end which opens at the following position: The opening 22a on the other end of the first bleed hole 22 opens at a position where the trajectory of the opening 22a during one rotation of the first orbiting scroll 2 is between the first annular groove 5A3 and the first annular groove 5A4 on the surface of the thrust plate 5A that faces the first swing base plate 2a. The second bleed hole 42 has an opening on one end which communicates with the second compression chamber 31, and an opening 42a on the other end which opens at the following position: The opening 42a on the other end of the first bleed hole 22 opens at a position where the trajectory of the opening 42a during one rotation of the second orbiting scroll 4 is between the second annular groove 5B3 and the second annular groove 5B4 on the surface of the thrust plate 5B that faces the second swing base plate 4a.

[0094] As described above, the scroll compressor 1000 of Embodiment 3 provides the same effects as those of Embodiment 1, and also provides the following effects by having the first back pressure chamber 61 and the second back pressure chamber 62, as with the scroll compressor 1000 of Embodiment 2. By having the first back pressure chamber 61 and the second back pressure chamber 62, the scroll compressor 1000 of Embodiment 3 can reduce refrigerant leakage from the first compression chamber 30 and the second compression chamber 31, thereby providing a compressor with high capacity and high power consumption reduction effects.

[0095] Fourth Embodiment Fig. 10 is a schematic longitudinal cross-sectional view showing an internal flow path within the thrust plate 5 of a scroll compressor 1000 according to a fourth embodiment. Fig. 11 is a perspective view of a flow path component 90 of the scroll compressor 1000 according to the fourth embodiment. In the fourth embodiment, only the structure different from the first to third embodiments will be described. In the fourth embodiment, the configuration of the first internal flow path 5A2 and the second internal flow path 5B2 formed in the thrust plate 5 differs from the first to third embodiments. Note that Fig. 10 shows an example in which the flow path component 90 is arranged in the scroll compressor 1000 according to the second embodiment shown in Fig. 7, but the flow path component 90 may also be arranged in the scroll compressor 1000 according to the first or third embodiment.

[0096] Since the first internal flow path 5A2 and the second internal flow path 5B2 have the same configuration, the first internal flow path 5A2 will be described below.

[0097] In the first embodiment, the first internal flow path 5A2 in the thrust plate 5 is configured with a straight radial flow path extending in the radial direction and a straight axial flow path extending in the axial direction. In the fourth embodiment, at least a portion of the first internal flow path 5A2 is configured with a spiral flow path 93 extending in a spiral shape. More specifically, the radial flow path of the first internal flow path 5A2 is configured with the spiral flow path 93. The spiral flow path 93 is configured by inserting a flow path component 90 into a radial hole that configures the radial flow path.

[0098] 10 , the flow path part 90 is a cylindrical rod-shaped member having a configuration in which a threaded spiral groove 91 is machined on the outer circumferential surface. In the scroll compressor 1000, the flow path part 90 is inserted into the radial hole of the thrust plate 5 with a clearance fit, thereby forming a spiral flow path 93 between the spiral groove 91 of the flow path part 90 and the inner circumferential surface of the radial hole. The radial hole of the first internal flow path 5A2 extends radially outward and opens into the outer circumferential surface of the thrust plate 5, and the opening is sealed with a hexagon socket set screw 92 or the like.

[0099] Since the first internal flow passage 5A2 is a flow passage that connects the suction space with the internal space 6a of the shaft hole 6 of the thrust plate 5, which is under discharge pressure, it is necessary to ensure sufficient resistance from the viewpoint of suppressing leakage. Therefore, if the first internal flow passage 5A2 has a straight shape, the first internal flow passage 5A2 needs to be formed with a very small hole diameter. However, it is difficult to machine a hole with a very small diameter.

[0100] In the scroll compressor 1000 of the fourth embodiment, at least a partial section of each of the first internal flow path 5A2 and the second internal flow path 5B2 is configured as a spiral flow path. In the scroll compressor 1000, at least a partial section of each of the first internal flow path 5A2 and the second internal flow path 5B2 is configured as a spiral flow path, and the length of the flow path is increased and the cross-sectional area of ​​the flow path is reduced, thereby ensuring sufficient flow path resistance.

[0101] The spiral flow path is formed by inserting the flow path component 90 into a radial hole provided in the thrust plate 5, so it is not necessary to form a hole with a very small diameter in the thrust plate 5; it is sufficient to form a hole large enough to insert the flow path component 90.

[0102] Therefore, the scroll compressor 1000 can improve workability while ensuring sufficient flow path resistance in the first internal flow path 5A2 and the second internal flow path 5B2.

[0103] As described above, the scroll compressor 1000 of embodiment 4 provides the same effects as those of embodiments 1 to 3, and also provides the following effect by providing the spiral flow path 93 in at least a partial section of each of the first internal flow path 5A2 and the second internal flow path 5B2. The scroll compressor 1000 of embodiment 4 can ensure sufficient flow path resistance in the first internal flow path 5A2 and the second internal flow path 5B2. Furthermore, the spiral flow path 93 can be formed by inserting a rod-shaped flow path component 90 having a spiral groove formed on its outer peripheral surface into a hole provided in the thrust plate 5, without forming a hole with a small diameter in the thrust plate 5. This facilitates processing, thereby improving workability.

[0104] 1 First fixed scroll, 1A Bearing, 1B Discharge port, 1a First fixed base plate, 1b First fixed volute, 2 First orbiting scroll, 2A Bearing, 2B Oldham keyway, 2a First orbiting base plate, 2b First orbiting volute, 3 Second fixed scroll, 3A Bearing, 3B Discharge port, 3a Second fixed base plate, 3b Second fixed volute, 4 Second orbiting scroll, 4A Bearing, 4B Oldham keyway, 4a Second orbiting base plate, 4b Second orbiting volute, 5 Thrust plate, 5A Thrust plate, 5A1 Oldham keyway, 5A2 First internal flow path, 5A3 First annular groove, 5A4 First annular groove, 5B Thrust plate, 5B1 Oldham keyway, 5B2 Second internal flow path, 5B3 Second annular groove, 5B4 Second annular groove, 6 Shaft hole, 6a Internal space, 7 Rotating shaft, 7A First shaft portion, 7B Second shaft portion, 7C Eccentric shaft portion, 7C1 First eccentric shaft portion, 7C2 Second eccentric shaft portion, 8 Compression mechanism, 8A First compression portion, 8B Second compression portion, 10 Oldham ring, 11 Oldham ring, 12 Reed valve, 13 Valve retainer, 14 Reed valve, 15 Valve retainer, 16 First balance weight, 17 Second balance weight, 18 Discharge muffler, 18A Discharge hole, 19 Discharge muffler, 20 Back surface, 20a Annular portion, 20b Annular portion, 20c Annular portion, 21a First annular groove, 21a1 Seal ring, 21b First annular groove, 21b1 Seal ring, 22 First bleed hole, 22a Opening, 30 First compression chamber, 31 Second compression chamber, 40 Back surface, 41a Second annular groove, 41a1 Seal ring, 41b Second annular groove, 41b1 Seal ring, 42 Second bleed hole, 42a Opening, 61 First back pressure chamber, 62 Second back pressure chamber, 70 Rotating plate, 71 Oil supply hole, 71a Axial hole, 71b Radial hole, 71b1 Radial hole, 71b2 Radial hole, 71b3 Radial hole, 71b4 Radial hole, 71b5 Radial hole, 72 Stirrer, 80 First space, 81 Second space, 82 Oil reservoir space, 83 Communication flow path, 84 Communication flow path, 90 Flow path parts, 91 Spiral groove, 92 Hexagon socket set screw, 93 Spiral flow path, 100 Sealed container, 101 Suction pipe, 102 Suction pipe, 103 Discharge pipe, 104 Glass terminal, 104a Lead wire, 200 Electric mechanism, 200A Air hole, 201 rotor, 202 stator, 300 refrigerating machine oil, 400 discharge pressure, 401 intermediate pressure, 402 suction pressure1000 Scroll compressor.

Claims

1. A compressor comprising: a compression mechanism that compresses a refrigerant; and a rotating shaft that drives the compression mechanism, wherein the compression mechanism comprises: a first compression section through which the rotating shaft passes; a second compression section through which the rotating shaft passes and which is arranged alongside the first compression section in the axial direction of the rotating shaft; and a thrust plate arranged between the first compression section and the second compression section in the axial direction, wherein the first compression section comprises: a first fixed scroll having a first fixed base plate and a first fixed spiral formed on one surface of the first fixed base plate; and a first oscillating scroll having a first oscillating base plate and a first oscillating spiral formed on one surface of the first oscillating base plate and meshing with the first fixed spiral to form a first compression chamber, and wherein the second compression section comprises: a second fixed scroll having a second fixed base plate and a second fixed spiral formed on one surface of the second fixed base plate; a second oscillating scroll having a second oscillating bed plate and a second oscillating volute formed on one surface of the second oscillating bed plate and meshing with the second fixed volute to form a second compression chamber, wherein the other surface of the first oscillating bed plate, which is a back surface, and the other surface of the second oscillating bed plate, which is a back surface, are arranged opposite each other with the thrust plate sandwiched therebetween.

2. A scroll compressor according to claim 1, wherein the rotating shaft has a first eccentric shaft portion that drives the first orbiting scroll and a second eccentric shaft portion that drives the second orbiting scroll, and the first eccentric shaft portion and the second eccentric shaft portion are arranged in opposite phases to each other.

3. A scroll compressor according to claim 1 or claim 2, wherein a first back pressure chamber is formed between the first oscillating plate and the thrust plate, the first back pressure chamber being airtightly separated from the surrounding space, the first back pressure chamber being connected to the first compression chamber by a first bleed hole provided in the first oscillating plate, and applying pressure to the back surface of the first oscillating plate during compression; and a second back pressure chamber is formed between the second oscillating plate and the thrust plate, the second back pressure chamber being airtightly separated from the surrounding space, the second back pressure chamber being connected to the second compression chamber by a second bleed hole provided in the second oscillating plate, and applying pressure to the back surface of the second oscillating plate during compression.

4. A scroll compressor according to claim 3, wherein two concentric first annular grooves are formed on one of the back surface of the first oscillating bedplate and the surface of the thrust plate facing the first oscillating bedplate, and the first back pressure chamber is formed between the first oscillating bedplate and the thrust plate by two annular seal rings inserted into the two first annular grooves, and two concentric second annular grooves are formed on one of the back surface of the second oscillating bedplate and the surface of the thrust plate facing the second oscillating bedplate, and the second back pressure chamber is formed between the second oscillating bedplate and the thrust plate by two annular seal rings inserted into the two second annular grooves.

5. A scroll compressor according to any one of claims 1 to 4, wherein the thrust plate is divided into two in the axial direction.

6. A scroll compressor as set forth in any one of claims 1 to 5, wherein the first compression section has a first anti-rotation mechanism that connects the first orbiting scroll and the thrust plate so that they can swing freely and prevents the first orbiting scroll from rotating on its axis, and the second compression section has a second anti-rotation mechanism that connects the second orbiting scroll and the thrust plate so that they can swing freely and prevents the second orbiting scroll from rotating on its axis.

7. A scroll compressor as set forth in any one of claims 1 to 6, wherein the thrust plate is formed with: a first internal flow path consisting of a hole having one end opening to the inner circumferential surface of the axial hole of the thrust plate and the other end opening to the surface of the thrust plate facing the first oscillating base plate; and a second internal flow path consisting of a hole having one end opening to the inner circumferential surface of the axial hole of the thrust plate and the other end opening to the surface of the thrust plate facing the second oscillating base plate.

8. A scroll compressor according to claim 7, wherein each of said first internal flow passage and said second internal flow passage has a spiral flow passage extending in a spiral shape in at least a partial section.

9. A scroll compressor according to claim 8, wherein said spiral flow path is formed by inserting a rod-shaped flow path component having a spiral groove formed on its outer circumferential surface into a hole provided in said thrust plate.

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