Scroll Compressor

Abstract

To provide a scroll compressor capable of compatibly suppressing a decline in the efficiency of the compressor due to the leakage of refrigerant or oil and reducing the slide loss.SOLUTION: A scroll compressor is constructed so that Ls is longer than minimum La, where La is the shortest distance (a compression chamber seal length) from a point between a fixed scroll lap 124b and a turning scroll lap 126b contacting each other on the outermost periphery to an inner peripheral edge 124d of an annular oil supply groove 124c at a crank angle α of α>0° when a crank angle of 0°is set at the time of completing the closure of refrigerant, and Ls is the shortest distance from a point between the fixed scroll lap 124b and the turning scroll lap 126b contacting each other on the outermost periphery to the inner peripheral edge 124d of the annular oil supply groove 124c or the shortest distance (a suction part seal length) from an outer peripheral edge 128f of a suction part 128c to the inner peripheral edge 124d of the annular oil supply groove 124c at a crank angle of 0°.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure particularly relates to scroll compressors used in refrigeration devices such as air conditioners and refrigerators, or heat pump type hot water devices. [Background technology]

[0002] Patent Document 1 discloses a scroll compressor. In general, when compressing a refrigerant, this type of scroll compressor generates a force (hereinafter referred to as a "push-back force") that tries to separate the fixed scroll and the orbiting scroll from each other. When the two scrolls are separated, refrigerant or oil leaks from the compression chamber, and the compressor efficiency decreases due to deterioration of volumetric efficiency and compression efficiency. For this reason, a back pressure chamber is formed on the back surface of the fixed scroll or the orbiting scroll. The back pressure chamber holds a back pressure for generating a force (hereinafter referred to as a "pressing force") that presses the fixed scroll or the orbiting scroll against the other scroll. The pressure in the back pressure chamber is set to an arbitrary pressure between the suction pressure and the discharge pressure. This pressing force prevents the fixed scroll and the orbiting scroll from being separated, and reduces a decrease in compressor efficiency due to leakage of refrigerant or oil. However, if the pressing force becomes excessive, the loss due to sliding between the fixed scroll end plate and the orbiting scroll end plate increases, and the compressor efficiency decreases. Therefore, in the scroll compressor disclosed in Patent Document 1, an annular oil groove communicating with the back pressure chamber is formed on the sliding surface of the fixed scroll end plate that contacts the orbiting scroll end plate, and a plurality of oil grooves having an arc shape or a linear shape, etc., and one end of which is open, are arranged at approximately equal pitch in the annular oil groove, thereby reducing the sliding loss between the fixed scroll end plate and the orbiting scroll end plate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 7-208356 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a scroll compressor that achieves both suppression of a decrease in compressor efficiency due to leakage of refrigerant or oil and reduction of sliding loss. [Means for solving the problem]

[0005] A scroll compressor according to the present disclosure includes a sealed container and a compression mechanism unit disposed within the sealed container and configured to compress a refrigerant, the compression mechanism unit including a fixed scroll and an orbiting scroll, the fixed scroll having a fixed scroll end plate and a spiral fixed scroll wrap rising from the fixed scroll end plate, the orbiting scroll having an orbiting scroll end plate and a spiral orbiting scroll wrap rising from the orbiting scroll end plate, the fixed scroll wrap and the orbiting scroll wrap being engaged with each other to form a plurality of compression chambers between the fixed scroll wrap and the orbiting scroll wrap, the compression chambers having an outer compression chamber positioned outside the orbiting scroll wrap, an inner compression chamber positioned inside the orbiting scroll wrap, an intake portion positioned at the outermost periphery of the compression chamber and configured to guide suction pressure refrigerant into the compression chamber, and a discharge portion positioned at the innermost periphery of the compression chamber and configured to discharge discharge pressure refrigerant from the interior of the compression chamber into the sealed container, the outer compression chamber having a discharge portion disposed at the inner A scroll compressor having a volume larger than that of a compression chamber when the refrigerant has been completely trapped, an annular oil groove is formed on a sliding surface of the fixed scroll end plate which contacts the orbiting scroll end plate, and the pressure in the annular oil groove is any pressure between a suction pressure and a discharge pressure. The scroll compressor has a seal portion surrounded by an inner peripheral edge of the annular oil groove, an outer peripheral edge of the outer compression chamber, and a suction portion, and when the crank angle is 0°, the fixed scroll end plate is provided with a seal portion surrounded by an inner peripheral edge of the annular oil groove, an outer peripheral edge of the outer compression chamber, and a suction portion, and when the crank angle α is α>0°, the seal portion is provided with a seal portion surrounded by an inner peripheral edge of the annular oil groove, an outer peripheral edge of the suction portion, and when the crank angle α is α>0°, The shortest distance (compression chamber seal length) from the point where the fixed scroll wrap and the orbiting scroll wrap contact at their outermost circumference to the inner peripheral edge of the annular oil groove is defined as Lα, and at the crank angle of 0°, the shortest distance from the point where the fixed scroll wrap and the orbiting scroll wrap contact at their outermost circumference to the inner peripheral edge of the annular oil groove, and the shortest distance (suction section seal length) from the outer peripheral edge of the suction section to the inner peripheral edge of the annular oil groove are defined as Ls. The configuration is such that Ls is greater than the minimum Lα. Effect of the Invention

[0006] The scroll compressor according to the present disclosure can reduce leakage of refrigerant and oil by ensuring a seal length in the suction section where the pressure difference with the annular oil groove is large, thereby making it possible to both suppress a decrease in compressor efficiency due to a deterioration in volumetric efficiency and reduce sliding loss. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a vertical cross-sectional view of a scroll compressor according to a first embodiment. [Diagram 2] FIG. 3 is an enlarged longitudinal sectional view of the scroll compressor; [Diagram 3] FIG. 2 is a cross-sectional view of the fixed scroll and the orbiting scroll in the first embodiment taken along line AA in FIG. [Figure 4] Illustrative diagram of suction seal length Ls [Diagram 5] Illustrative diagram of compression chamber seal length Lα [Figure 6] FIG. 2 is a cross-sectional view of a fixed scroll and an orbiting scroll according to a second embodiment taken along line AA in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] (The knowledge and other information that formed the basis of this disclosure) At the time the inventors came up with the idea of ​​this disclosure, scroll compressors had an annular oil groove communicating with a back pressure chamber formed on the sliding surface of the fixed scroll end plate against the orbiting scroll end plate, and a plurality of oil grooves, each having an arc shape or a linear shape with one end open, arranged at approximately equal pitches in the annular oil groove in order to reduce sliding loss between the fixed scroll end plate and the orbiting scroll end plate, as described in Patent Document 1. This improved lubrication of the sliding surface between the fixed scroll end plate and the orbiting scroll end plate and made it possible to reduce the sliding area. However, no consideration was given to the leakage of refrigerant or oil from the back pressure chamber to the suction section or from the back pressure chamber to the compression chamber at the sliding surface between the fixed scroll end plate and the orbiting scroll end plate. As a result, there was a possibility that refrigerant or oil would leak from the compression chamber, particularly at the suction section located at the outermost periphery of the compression chamber and where the pressure difference with the annular oil groove is large, resulting in a decrease in compressor efficiency. The inventors have discovered this problem and have come to define the subject matter of the present disclosure.

[0009] Therefore, the present disclosure provides a scroll compressor that achieves both suppression of a decrease in compressor efficiency due to leakage of refrigerant or oil and reduction of sliding loss.

[0010] Hereinafter, the embodiments will be described in detail with reference to the drawings. However, more detailed description than necessary may be omitted. For example, detailed description of already well-known matters or duplicate description of substantially the same configuration may be omitted. It should be noted that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0011] (Embodiment 1) The first embodiment will be described below with reference to FIGS. 1 to 5. FIG.

[0012] [1-1. Configuration] FIG. 1 is a longitudinal cross-sectional view of a scroll compressor 100, FIG. 2 is an enlarged longitudinal cross-sectional view of a main portion of the same scroll compressor, FIG. 3 is a cross-sectional view taken along line AA in FIG. 1 of a fixed scroll 124 and a rotating scroll 126, FIG. 4 is an explanatory diagram of the suction section seal length Ls, and FIG. 5 is an explanatory diagram of the compression chamber seal length Lα.

[0013] As shown in FIG. 1, the scroll compressor 100 includes a sealed container 110, a compression mechanism unit 120 disposed within the sealed container 110, and a motor unit 130 that drives the compression mechanism unit 120, and oil 140 is stored at the bottom of the sealed container 110. A suction pipe 112 and a discharge pipe 114 are attached to the sealed container 110. In this embodiment, the suction pipe 112 is attached to the side surface of the sealed container 110, and the discharge pipe 114 is attached to the top surface of the sealed container 110.

[0014] As shown in FIG. 2, the compression mechanism 120 includes a main bearing member 122 fixed in the sealed container 110 by welding or shrink fitting, a fixed scroll 124 bolted onto the main bearing member 122, and an orbiting scroll 126 disposed on the upper part of the main bearing member 122 so as to face the fixed scroll 124. The fixed scroll 124 includes a fixed scroll end plate 124a and a spiral fixed scroll wrap 124b rising from the fixed scroll end plate 124a. The orbiting scroll 126 includes a orbiting scroll end plate 126a and a spiral orbiting scroll wrap 126b rising from the orbiting scroll end plate 126a. A plurality of compression chambers 128 are formed by meshing the fixed scroll wrap 124b and the orbiting scroll wrap 126b. A muffler 121 is provided on the back surface of the fixed scroll 124, and a discharge pressure chamber 127 is formed between the muffler 121 and the back surface of the fixed scroll 124. Inside the orbiting scroll 126, a connection passage 126c and a supply passage 126d are provided to guide the oil 140 from the bottom of the sealed container 110 to the compression chamber 128. A seal member 116 is provided on the back surface of the orbiting scroll end plate 126a. As a result, a high pressure region 118 that maintains discharge pressure is formed inside the seal member 116, and a back pressure chamber 129 that maintains back pressure that presses the orbiting scroll 126 against the fixed scroll 124 is formed outside the seal member 116. Between the main bearing member 122 and the orbiting scroll 126, there is provided a rotation restraint mechanism 123 such as an Oldham ring that prevents the orbiting scroll 126 from rotating and guides it to move in a circular orbit.

[0015] 1, the motor section 130 includes a stator 132 fixed to the sealed container 110 by welding or shrink fitting, and a rotor 134 incorporating a permanent magnet arranged on the inner periphery side of the stator 132. A crankshaft 136 is fixed to the rotor 134. The crankshaft 136 is supported by the main bearing member 122 and a sub-bearing member 138 provided near the bottom of the sealed container 110. The crankshaft 136 includes a main shaft portion 136a and an eccentric shaft portion 136b formed eccentrically with respect to the main shaft portion 136a. The eccentric shaft portion 136b is fitted into an orbiting bearing 126f provided in a boss portion 126e on the back surface of the orbiting scroll 126. An oil supply hole 136c is provided inside the crankshaft 136 so as to pass through in the axial direction, and the main shaft portion 136a is fitted into an oil pump 142 fixed to the sub-bearing member 138 by bolts. The oil pump 142 is positioned so that its suction port is reliably inserted into the oil 140 .

[0016] 3, the compression chamber 128 formed by the fixed scroll wrap 124b and the orbiting scroll wrap 126b includes an outer compression chamber 128a located outside the orbiting scroll wrap 126b and an inner compression chamber 128b located inside the orbiting scroll wrap 126b. The compression chamber 128 has a suction section 128c at its outermost periphery for introducing suction pressure refrigerant into the compression chamber 128, and a discharge section 128d at its innermost periphery for discharging discharge pressure refrigerant from the inside of the compression chamber 128 into the sealed container 110. The outer compression chamber 128a has a larger volume than the inner compression chamber 128b when the refrigerant is completely trapped. An annular oil supply groove 124c is provided on the outer periphery of the fixed scroll 124, and communicates with the back pressure chamber 129 to receive the refrigerant and oil 140 therein. In the fixed scroll 124, a seal portion 125 that comes into sliding contact with the orbiting scroll end plate 126a is formed in an area surrounded by an inner peripheral edge 124d of the annular oil groove 124c and an outer peripheral edge 128e of the compression chamber 128.

[0017] Inner peripheral edge 124d of annular oil groove 124c is configured as a circle. For example, when the point at which outer compression chamber 128a completes trapping of the refrigerant is defined as a crank angle of 0°, center 124f of inner peripheral edge 124d of annular oil groove 124c is defined as Ls, which is the shortest distance from the point at which fixed scroll wrap 124b and orbiting scroll wrap 126b contact each other at the outermost circumference to inner peripheral edge 124d of annular oil groove 124c and the shortest distance from outer peripheral edge 128f of suction portion 128c to inner peripheral edge 124d of annular oil groove 124c at a crank angle of 0°, as shown in FIG. 5, the center 124f of the inner circumferential edge 124d of the annular oil groove 124c is eccentric toward the suction section 128c from the point where the fixed scroll wrap 124b and the orbiting scroll wrap 126b contact each other at their outermost circumferences when the crank angle α is α>0°, so that Lα is the shortest distance (compression chamber seal length). In this case, the center 124f is eccentric toward the suction section 128c from the fixed scroll center 124e so that Lα is larger than the minimum Lα (Lαmin).

[0018] [1-2. Operation] The operation and function of the scroll compressor 100 configured as above will be described below. When the motor section 130 is energized, a magnetic field generated in the stator 132 causes the rotor 134 to rotate together with the crankshaft 136 . As the crankshaft 136 rotates, the oil pump 142 is driven, and the oil 140 stored in the bottom of the sealed container 110 is reliably sucked up regardless of the pressure conditions or operating speed. This eliminates the concern of running out of oil. The oil 140 sucked up by the oil pump 142 is supplied to the compression mechanism 120 through the oil supply hole 136c. If foreign matter is removed from the oil 140 using an oil filter or the like before or after the oil pump 142 sucks up the oil 140, it is possible to prevent foreign matter from entering the compression mechanism 120, thereby improving reliability. The oil 140 supplied to the compression mechanism 120 has a pressure substantially equal to that of the refrigerant discharged from the scroll compressor 100, and serves as a back pressure source for the orbiting scroll 126. When the connection passage 126c faces the outside of the seal member 116 (back pressure chamber 129), a part of the oil 140 is guided to the back pressure chamber 129 due to a pressure difference. Conversely, when the connection passage 126c faces the inside of the seal member 116 (high pressure region 118), no pressure difference occurs, and the oil 140 does not flow into the back pressure chamber 129. The oil 140 guided to the back pressure chamber 129 lubricates the sliding surfaces of the fixed scroll end plate 124a and the orbiting scroll end plate 126a through the annular oil supply groove 124c. The remaining oil 140 flows into the fitting portion between the eccentric shaft portion 136b and the rotary bearing 126f and the fitting portion between the main shaft portion 136a and the main bearing member 122, lubricating each of these portions, and then returns to the bottom of the sealed container 110.

[0019] Furthermore, as the crankshaft 136 rotates, the eccentric shaft portion 136b rotates eccentrically with respect to the main shaft portion 136a, causing the orbiting scroll 126 to orbit. The orbiting scroll 126 is eccentrically driven by the eccentric shaft portion 136b and is caused to move in a circular orbit by the rotation restraint mechanism 123, thereby changing the volume of the compression chamber 128.

[0020] The refrigerant drawn from the suction pipe 112 is guided to the compression chamber 128 via the suction section 128c. The refrigerant drawn into the compression chamber 128 moves from the outer periphery toward the center while decreasing in volume, and is pressurized. At this time, the annular oil groove 124c is enlarged in order to reduce the sliding area between the fixed scroll end plate 124a and the orbiting scroll end plate 126a. This makes it easier for the refrigerant and oil 140 to leak from the suction section 128c, which is located at the outermost periphery and has a large pressure difference with the inside of the annular oil groove 124c, and may lead to a decrease in compressor efficiency due to deterioration in volumetric efficiency and compression efficiency.

[0021] In this embodiment, the center 124f of the inner peripheral edge 124d of the annular oil supply groove 124c is eccentric from the fixed scroll center 124e toward the suction portion 128c so that Lαmin < Ls. Therefore, Lαmin exists in a region where the difference between the pressure in the annular oil supply groove 124c and the pressure in the compression chamber 128 is small on the side opposite to the eccentric direction. That is, in the suction portion 128c where the difference from the pressure in the annular oil supply groove 124c is large, the seal length is large, and in a region where the difference between the pressure in the annular oil supply groove 124c and the pressure in the compression chamber 128 is small, the seal length is small. The leakage amount of the refrigerant and the oil 140 is proportional to the pressure difference and inversely proportional to the seal length. Thereby, the leakage of the refrigerant and the oil 140 in the suction portion 128c can be reduced without increasing the leakage amount of the refrigerant and the oil 140 in the compression chamber 128.

[0022] Then, the refrigerant that has reached the discharge pressure is discharged from the innermost discharge portion 128d to the discharge pressure chamber 127. The refrigerant discharged into the discharge pressure chamber 127 fills the inside of the sealed container 110 and is discharged out of the sealed container 110 through the discharge pipe 114.

[0023] [1-3. Effects, etc.] As described above, in this embodiment, the scroll compressor 100 eccentrically positions the center 124f of the inner peripheral edge 124d of the annular oil supply groove 124c from the fixed scroll center 124e toward the suction portion 128c. Thereby, the seal length can be increased in the suction portion 128c located at the outermost periphery of the compression chamber 128 and having a large pressure difference from the inside of the annular oil supply groove 124c, and the seal length can be decreased in a region where the pressure difference between the inside of the annular oil supply groove 124c and the compression chamber 128 is small. Thereby, even if the annular oil supply groove 124c is enlarged to reduce the sliding area between the fixed scroll end plate 124a and the orbiting scroll end plate 126a, the leakage of the refrigerant and the oil 140 can be surely reduced. Thereby, it is possible to achieve both suppression of a decrease in compressor efficiency due to deterioration of volumetric efficiency and compression efficiency and reduction of sliding loss.

[0024] (Embodiment 2) Embodiment 2 will be described below with reference to FIG. 6.

[0025] [2-1. Configuration] FIG. 6 is a cross-sectional view taken along line A-A of FIG. 1, showing the fixed scroll 224 and the orbiting scroll 126 when the pressure in the outermost outer compression chamber 228a is equal to the pressure in the annular oil supply groove 224c, as seen in the direction of the arrow. As shown in FIG. 6, the scroll compressor 200 of the second embodiment is different from the scroll compressor 100 according to the first embodiment only in that the fixed scroll 224 is different, and the other configurations, operations, and effects are the same as those of the first embodiment, so the description thereof is omitted. Note that the fixed scroll wrap 124b, the inner compression chamber 128b, the suction part 128c, and the outer peripheral edge 128f of the suction part described in the first embodiment are shown as the fixed scroll wrap 224b, the inner compression chamber 228b, the suction part 228c, and the outer peripheral edge 228f in the second embodiment. An annular oil supply groove 224c is provided on the outer peripheral part of the fixed scroll 224, through which the refrigerant and the oil 140 are supplied by communicating with the back pressure chamber 129. A seal part 225 that is in sliding contact with the orbiting scroll mirror plate 226a is formed in the range surrounded by the inner peripheral edge 224d of the annular oil supply groove 224c of the fixed scroll 224 and the outer peripheral edge 228e of the compression chamber 228. The inner peripheral edge 224d of the annular oil supply groove 224c is composed of a plurality of arcs having different curvatures, and Lαmin < Ls. Also, in the range where the pressure in the annular oil supply groove 224c is higher than the pressure in the compression chamber 228, as the crank angle α advances (increases), Lα gradually decreases. Also, in the range where the pressure in the annular oil supply groove 224c is lower than the pressure in the compression chamber 228, as the crank angle α advances, Lα gradually increases.

[0026] [2-2. Effects, etc.] As described above, in the scroll compressor 200 of the present embodiment, in a range in which the pressure in the annular oil groove 224c is higher than the pressure in the compression chamber 228, Lα gradually decreases as the crank angle α advances. In addition, in a range in which the pressure in the annular oil groove 224c is lower than the pressure in the compression chamber 228, Lα gradually increases as the crank angle α advances. As with the scroll compressor 100 according to the first embodiment, the scroll compressor 200 can reduce the sliding area between the fixed scroll end plate 224a and the orbiting scroll end plate 126a while reliably suppressing leakage of the refrigerant or oil 140. Therefore, it is possible to simultaneously suppress a decrease in compressor efficiency due to deterioration in volumetric efficiency and compression efficiency, and reduce sliding loss. Furthermore, in the scroll compressor 200, the inner peripheral edge 224d of the annular oil groove 224c is composed of a plurality of arcs having different curvatures, so that the seal length can be increased in the range where the pressure difference between the annular oil groove 224c and the compression chamber 228 is large, and the seal length can be decreased in the range where the pressure difference between the annular oil groove 224c and the compression chamber 228 is small, throughout the entire compression chamber 228. Therefore, the scroll compressor 200 can reduce the sliding area between the fixed scroll end plate 224a and the orbiting scroll end plate 126a more than the scroll compressor 100 according to the first embodiment while reliably suppressing leakage of the refrigerant and oil 140. Therefore, the sliding loss can be reduced more than the scroll compressor 100 according to the first embodiment. [Industrial Applicability]

[0027] INDUSTRIAL APPLICABILITY The scroll compressor according to the present disclosure can suppress a decrease in compressor efficiency while reducing sliding losses, and is useful for air conditioners, heat pump water heaters, hot water heating systems, refrigeration cycle devices such as refrigerators, and the like. [Explanation of symbols]

[0028] 100, 200 Scroll compressor 110 Airtight container 112 Suction pipe 114 Discharge pipe 116 Sealing material 118 High Pressure Region 120 Compression mechanism 121 Muffler 122 Main bearing parts 123 Rotation Restraint Mechanism 124, 224 Fixed Scroll 124a, 224a Fixed scroll head plate 124b, 224b fixed scroll wrap 124c, 224c Annular oil groove 124d, 224d Inner edge of annular oil groove 124e Fixed scroll center 124f Center of inner periphery of annular oil groove 125, 225 Seal part 126 Swivel Scroll 126a, 226a Rotating scroll head plate 126b Swivel Scroll Wrap 126c Connection 126d Supply route 126e Boss part 126f Slewing bearing 127 Discharge pressure chamber 128, 228 Compression chamber 128a, 228a Outer compression chamber 128b, 228b inner compression chamber 128c, 228c suction part 128d Discharge part 128e, 228e Outer periphery of compression chamber 128f, 228f Outer edge of intake 129 Back pressure chamber 130 Motor section 132 Stator 134 Rotor 136 Crankshaft 136a Main shaft part 136b Eccentric shaft part 136c Oil hole 138 Secondary bearing member 140 Oil 142 Oil pump

Claims

1. A compressor includes a sealed container and a compression mechanism that is disposed in the sealed container and compresses a refrigerant. The compression mechanism includes a fixed scroll and a rotating scroll, The fixed scroll has a fixed scroll end plate and a spiral-shaped fixed scroll wrap rising from the fixed scroll end plate, The orbiting scroll has an orbiting scroll end plate and a spiral-shaped orbiting scroll wrap rising from the orbiting scroll end plate, By meshing the fixed scroll wrap and the orbiting scroll wrap, a plurality of compression chambers are formed between the fixed scroll wrap and the orbiting scroll wrap, the compression chamber has an outer compression chamber located outside the orbiting scroll wrap, an inner compression chamber located inside the orbiting scroll wrap, a suction section located on the outermost periphery of the compression chamber and directing a suction pressure refrigerant into the inside of the compression chamber, and a discharge section located on the innermost periphery of the compression chamber and discharging a discharge pressure refrigerant from the inside of the compression chamber into the inside of the sealed container, the outer compression chamber having a larger volume than the inner compression chamber when the refrigerant has been completely trapped, In a scroll compressor, an annular oil groove is formed on a sliding surface of the fixed scroll end plate which is in contact with the orbiting scroll end plate, and a pressure in the annular oil groove is set to any pressure between a suction pressure and a discharge pressure, a seal portion surrounded by an inner peripheral edge of the annular oil groove, an outer peripheral edge of the outer compression chamber, and an outer peripheral edge of the suction portion, a crank angle of 0° when the outer compression chamber has completed trapping the refrigerant, a shortest distance (compression chamber seal length) from a point where the fixed scroll wrap and the orbiting scroll wrap contact each other at their outermost circumferences to the inner peripheral edge of the annular oil groove when the crank angle α is α > 0°, and a shortest distance from a point where the fixed scroll wrap and the orbiting scroll wrap contact each other at their outermost circumferences to the inner peripheral edge of the annular oil groove and a shortest distance (suction portion seal length) from the outer peripheral edge of the suction portion to the inner peripheral edge of the annular oil groove when the crank angle α is 0°, wherein Ls is greater than the minimum Lα.

2. The inner peripheral edge of the annular oil groove is formed in a circle, and a center of the inner peripheral edge of the annular oil groove is eccentric from a center of an end plate of the fixed scroll.

2. The scroll compressor according to claim 1.

3. The inner circumferential edge of the annular oil groove is formed of a plurality of circular arcs having different curvatures.

2. The scroll compressor according to claim 1.

4. In a range in which the pressure in the annular oil groove is higher than the pressure in the compression chamber, As the crank angle α progresses, the Lα gradually decreases. The scroll compressor according to claim 1 or 3.

5. In a range in which the pressure in the annular oil groove is lower than the pressure in the compression chamber, As the crank angle α progresses, the Lα gradually increases. The scroll compressor according to claim 1, 3 or 4.

Images