EP3575602B1

EP3575602B1 - Scroll compressor

Info

Publication number: EP3575602B1
Application number: EP18745309.7A
Authority: EP
Inventors: Tsutomu Kon; Satoshi Iitsuka; Kazuya Sato; Daisuke Ogi; Akinori Fukuda; Hiroki TAGAMI
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2017-01-27
Filing date: 2018-01-17
Publication date: 2023-01-04
Anticipated expiration: 2038-01-17
Also published as: CN110234881B; JP2018119504A; WO2018139309A1; EP3575602A4; JP6709971B2; EP3575602A1; CN110234881A

Description

[TECHNICAL FIELD]

The present invention relates to a scroll compressor used for an air conditioner, a hot water supplying system and a freezing machine such as a refrigerator.

[BACKGROUND TECHNIQUE]

A scroll compressor is used in a freezing machine and an air conditioner. The scroll compressor sucks gas refrigerant evaporated by an evaporator, compresses the gas refrigerant up to pressure required for condensing the gas refrigerant by a condenser, and sends out the high temperature and high pressure gas refrigerant into a refrigerant circuit.
In such a scroll compressor, an oil storage section for storing lubricant oil therein is formed in a bottom of a hermetic container, and a rotation shaft oil support hole extending from a lower end of a rotation shaft to an eccentric shaft is formed. Lubricant oil stored in the oil storage section is introduced into the eccentric shaft through the rotation shaft oil support hole.
Therefore, when the compressor is actuated, there is a problem that a slight time delay is generated until lubricant oil is supplied from the oil storage section to the eccentric shaft. To solve the shortage of lubricant oil around the eccentric shaft generated when the compressor is again actuated, it is proposed to provide an oil reservoir in an upper surface of the eccentric shaft (patent document 1).
Patent document 2 discloses a scroll compressor including a casing, a compression mechanism, a crankshaft, a motor, and a lower oil reservoir.

[PRIOR ART DOCUMENTS]

[Patent Documents]

[Patent Document 1] Japanese Patent Application Laid-open No.S62-142885
[Patent Document 2] Japanese Patent Application Laid-open No. 2015-090093

[SUMMARY OF THE INVENTION]

[PROBLEM TO BE SOLVED BY THE INVENTION]

However, there is a case where lubricant oil guided to the eccentric shaft is further guided to an outer periphery of an orbiting scroll mirror plate, and when the compressor is again actuated, it is necessary to swiftly guide the lubricant oil from the oil reservoir to the outer periphery of the orbiting scroll mirror plate.
Hence, it is an object of the present invention to provide a scroll compressor capable of swiftly guiding lubricant oil which is stored in the oil reservoir when the compressor is stopped to the outer periphery of the orbiting scroll mirror plate by a centrifugal force when the compressor is again actuated.

[MEANS FOR SOLVING THE PROBLEM]

The present invention provides a scroll compressor as defined in appended claim 1. Preferred embodiments are set forth in the dependent claims.

[EFFECT OF THE INVENTION]

According to the present invention, lubricant oil stored in the oil reservoir when a compressor is stopped can swiftly be guided to an outer periphery of an orbiting scroll mirror plate by a centrifugal force when the compressor is again actuated.

[BRIEF DESCRIPTION OF THE DRAWINGS]

Fig. 1 is a vertical sectional view of a scroll compressor of an embodiment of the present invention;
Fig. 2 is an enlarged sectional view of essential portions of a compressing mechanism shown in Fig. 1;
Figs. 3 are plane views of a fixed scroll and an orbiting scroll shown in Figs. 1 and 2;
Figs. 4 are explanatory diagrams showing a supplying operation of lubricant oil existing in a boss portion into an intermediate pressure region;
Figs. 5 are explanatory diagrams showing a deriving operation of lubricant oil existing in the intermediate pressure region into a compression chamber;
Figs. 6 are explanatory diagrams showing a positional relation between a refueling pathway and a sealing member associated with orbiting motion of the scroll compressor;
Fig. 7 is a graph showing pressure variation of intermediate pressure which is taken out from an intermediate pressure extraction hole in the scroll compressor of the embodiment;
Fig. 8 is a graph showing pressure variation of intermediate pressure which is taken out from the intermediate pressure extraction hole in a scroll compressor as a comparative example; and
Fig. 9 is a graph showing pressure variation of intermediate pressure which is taken out from an intermediate pressure extraction hole in a scroll compressor as another comparative example.

[MODE FOR CARRYING OUT THE INVENTION]

In the present invention, an oil reservoir is formed in an upper surface of the eccentric shaft, and the oil reservoir is placed between a rotation shaft center of the rotation shaft and the first oil introduction hole. Accordingly, lubricant oil stored in the oil reservoir when the compressor is stopped, can swiftly be guided to the first oil introduction hole by a centrifugal force when the compressor is again actuated.
Moreover, the boss storing section is a high pressure region, an outer periphery of the orbiting scroll where the rotation restraining member is placed is an intermediate pressure region communicating with an intermediate pressure extraction hole in the compression chamber, and the orbiting scroll is pushed against the fixed scroll, the fixed scroll is provided with a fixed scroll sliding surface which slides with respect to the orbiting scroll mirror plate located closer to an outer periphery of the orbiting spiral lap than the orbiting spiral lap, the intermediate pressure region is formed on a location closer to the outer periphery of the orbiting spiral lap than the fixed scroll sliding surface, the fixed scroll sliding surface is provided with a sliding surface groove which is in communication with the intermediate pressure region, the lubricant oil stored in the oil storage section is introduced into the boss portion through the rotation shaft oil support hole, the lubricant oil introduced into the boss portion is introduced into the sliding surface groove through the first mirror plate oil communication path, and the lubricant oil introduced into the sliding surface groove is introduced into the intermediate pressure region. Accordingly, lubricant oil can intermittently be supplied to the intermediate pressure region by communication between a first oil derivation hole formed in an outer periphery of a lap-side end surface and the sliding surface groove formed in the fixed scroll sliding surface. Further, since the close contact state of the lap-side end surface and the fixed scroll sliding surface is maintained without separating them from each other, an amount of oil can be adjusted by the first oil derivation hole and the sliding surface groove, and it is easy to adjust the oil amount.
According to a first embodiment, the first oil derivation hole and the sliding surface groove are brought intocommunication with each other at a rotation position where an eccentric shaft center of the eccentric shaft comes closest to the sliding surface groove. Accordingly, the largest centrifugal force is applied to lubricant oil existing in the boss portion at a rotation position where the eccentric shaft center of the eccentric shaft comes closest to the sliding surface groove. Therefore, lubricant oil can reliably be introduced into the sliding surface groove by bringing the first oil derivation hole and the sliding surface groove into communication with each other when the largest centrifugal force is applied to the lubricant oil existing in the boss portion.
According to a second embodiment, as the compression chamber, a first compression chamber is formed on an outer wall side of the orbiting spiral lap, and a second compression chamber is formed on an inner wall side of the orbiting spiral lap, a suction volume of the first compression chamber is made larger than a suction volume of the second compression chamber, the fixed scroll mirror plate is provided with an intermediate pressure extraction hole through which intermediate pressure of the compression chamber is taken out, and an intermediate pressure communication path for bringing the intermediate pressure extraction hole and the intermediate pressure region into communication with each other is formed in the fixed scroll. Accordingly, especially under low compression ratio condition, it is possible to prevent the orbiting scroll from separating from the fixed scroll, and airtightness of the compression chamber can be enhanced.
According to a third embodiment, a high pressure communication path for bringing the intermediate pressure extraction hole and a high pressure space in the hermetic container into communication with each other is formed in the fixed scroll, and a balance valve is provided in a high pressure opening of the high pressure communication path. Accordingly, if intermediate pressure in mid-flow of compression of the compression chamber becomes excessively high, intermediate pressure in mid-flow of compression of the compression chamber is adjusted to predetermined pressure by opening the balance valve, and it is possible to reduce a compression ratio of the low compression ratio condition at which the orbiting scroll separates from the fixed scroll.
According to a fourth embodiment, the orbiting scroll mirror plate is provided with a second oil introduction hole which opens from the intermediate pressure region, a second oil derivation hole which opens from a low pressure space of the compression chamber and a second mirror plate oil communication path for bringing the second oil introduction hole and the second oil derivation hole into communication with each other, and the lubricant oil introduced into the intermediate pressure region is introduced in to the low pressure space of the compression chamber through the second mirror plate oil communication path. Accordingly, lubricant oil in the intermediate pressure region can be circulated by guiding, to the low pressure space of the compression chamber, lubricant oil which is guided to the intermediate pressure region, and it is possible to prevent oil from being deteriorated by shortage of oil supply in the intermediate pressure region and by accumulation of lubricant oil.

[EMBODIMENT]

An embodiment of the present invention will be described below with reference to the drawings. The invention is not limited to the embodiment.
Fig. 1 is a vertical sectional view of a scroll compressor of the embodiment.
An embodiment of the present invention will be described below with reference to the drawings. The invention is not limited to the embodiment.
Fig. 1 is a vertical sectional view of a scroll compressor of the embodiment.
A compressing mechanism 10 for compressing refrigerant and an electric mechanism 20 for driving the compressing mechanism 10 are placed in a hermetic container 1.
The hermetic container 1 is composed of a torso 1a extending along a vertical direction and formed into a cylindrical shape, an upper lid 1c for closing an upper opening of the torso 1a, and a lower lid 1b for closing a lower opening of the torso 1a.
The hermetic container 1 is provided with a refrigerant suction pipe 2 for introducing refrigerant into the compressing mechanism 10, and a refrigerant discharge pipe 3 for discharging refrigerant compressed by the compressing mechanism 10 to a location outside the hermetic container 1.
The compressing mechanism 10 includes a fixed scroll 11, an orbiting scroll 12 and a rotation shaft 13 for driving the orbiting scroll 12 in an orbiting manner.
The electric mechanism 20 includes a stator 21 fixed to the hermetic container 1, and a rotor 22 placed on an inner side of the stator 21. The rotation shaft 13 is fixed to the rotor 22. An eccentric shaft 13a which is decentered eccentrically with respect to the rotation shaft 13 is formed on an upper end of the rotation shaft 13.
An oil reservoir 80 is formed in the eccentric shaft 13a by a recess which opens from an upper surface of the eccentric shaft 13a.
A main bearing 30 which supports the fixed scroll 11 and the orbiting scroll 12 are provided below the fixed scroll 11 and the orbiting scroll 12.
A bearing 31 for pivotally supproting the rotation shaft 13, and a boss storing section 32 are formed in the main bearing 30. The main bearing 30 is fixed to the hermetic container 1 by welding or shrinkage fitting.
The fixed scroll 11 includes a disk-like fixed scroll mirror plate 11a, a fixed spiral lap 11b standing on the fixed scroll mirror plate 11a, and an outer peripheral wall 11c standing such that it surrounds a periphery of the fixed spiral lap 11b. A discharge port 14 is formed in a substantially center portion of the fixed scroll mirror plate 11a.
The orbiting scroll 12 includes a disk-like orbiting scroll mirror plate 12a, an orbiting spiral lap 12b standing on a on a lap-side end surface of the orbiting scroll mirror plate 12a, and a cylindrical boss portion 12c formed on an end surface of the orbiting scroll mirror plate 12a on an opposite side from the lap side.
The fixed spiral lap 11b of the fixed scroll 11 and the orbiting spiral lap 12b of the orbiting scroll 12 mesh with each other, and a plurality of compression chambers 15 are formed between the fixed spiral lap 11b and the orbiting spiral lap 12b.
The boss portion 12c is formed at a substantially central portion of the orbiting scroll mirror plate 12a. The eccentric shaft 13a is inserted into the boss portion 12c, and the boss portion 12c is stored in the boss storing section 32.
The fixed scroll 11 is fixed to a main bearing 30 at the outer peripheral wall 11c through a plurality of bolts 16. The orbiting scroll 12 is supported on the fixed scroll 11 through a rotation restraining member 17 such as an Oldham ring. The rotation restraining member 17 which restrains rotation of the orbiting scroll 12 is provided between the fixed scroll 11 and the main bearing 30. According to this, the orbiting scroll 12 orbits without rotating with respect to the fixed scroll 11.
A lower end 13b of the rotation shaft 13 is pivotally supported by an auxiliary bearing 18 placed on a lower portion of the hermetic container 1.
An oil storage section 4 for storing lubricant oil is formed in a bottom portion of the hermetic container 1.
A lower end of the rotation shaft 13 is provided with a displacement oil pump 5. The oil pump 5 is placed such that its suction port exists in the oil storage section 4. The oil pump 5 is driven by the rotation shaft 13. The oil pump 5 can reliably pump up lubricant oil existing in the oil storage section 4 provided in a bottom of the hermetic container 1 irrespectively of pressure condition or operation speed, and fear of shortage of oil is resolved.
A rotation shaft oil support hole 13c extending from the lower end 13b of the rotation shaft 13 to the eccentric shaft 13a is formed in the rotation shaft 13.
Lubricant oil pumped up by the oil pump 5 is supplied into a bearing of the auxiliary bearing 18, the bearing 31 and the boss portion 12c through the rotation shaft oil support hole 13c formed in the rotation shaft 13.
Refrigerant sucked from the refrigerant suction pipe 2 is guided from the suction port 15a into the compression chambers 15. The compression chambers 15 move while reducing their volumes from an outer peripheral side toward a central portion, refrigerant whose pressure reaches a predetermined value in the compression chambers 15 is discharged from a discharge port 14 provided in a central portion of the fixed scroll 11 into the discharge chamber 6. The discharge port 14 is provided with a discharge reed valve (not shown). The refrigerant whose pressure reaches a predetermined value in the compression chamber 15 pushes and opens the discharge reed valve and is discharged into the discharge chamber 6. The refrigerant which is discharged into the discharge chamber 6 is derived into an upper portion in the hermetic container 1, the refrigerant passes through a refrigerant passage (not shown) formed in the compressing mechanism 10, reaches a periphery of the electric mechanism 20, and is discharged from the refrigerant discharge pipe 3.
Fig. 2 is an enlarged sectional view of essential portions of the compressing mechanism shown in Fig. 1.
According to the scroll compressor of the embodiment, the boss storing section 32 is a high pressure region A, an outer periphery of the orbiting scroll 12 where the rotation restraining member 17 is placed is an intermediate pressure region B, and the orbiting scroll 12 is pushed against the fixed scroll 11.
The eccentric shaft 13a is inserted into the boss portion 12c through the orbiting bearing 13d such that the eccentric shaft 13a can orbit and drive. An oil groove 13e is formed in an outer peripheral surface of the eccentric shaft 13a.
A thrust surface of the main bearing 30 which receives thrust force of the orbiting scroll mirror plate 12a is provided with a ring-shaped sealing member 33. The sealing member 33 is placed on an outer periphery of the boss storing section 32.
The hermetic container 1 is filled with refrigerant having the same high pressure as refrigerant discharged into the discharge chamber 6. Since the rotation shaft oil support hole 13c opens from an upper end of the eccentric shaft 13a, an interior of the boss portion 12c becomes a high pressure region A which has the same pressure as a discharged refrigerant.
Lubricant oil which is introduced into the boss portion 12c through the rotation shaft oil support hole 13c is supplied to the orbiting bearing 13d and the boss storing section 32 by the oil groove 13e formed in the outer peripheral surface of the eccentric shaft 13a. Since the outer periphery of the boss storing section 32 is provided with the sealing member 33, the boss storing section 32 is the high pressure region A.
The fixed scroll mirror plate 11a is provided with an intermediate pressure extraction hole 41 through which intermediate pressure of the compression chamber 15 is taken out, a mirror plate-side intermediate pressure communication path 42a which is in communication with the intermediate pressure extraction hole 41, and a high pressure communication path 71 which brings the intermediate pressure extraction hole 41 and a high pressure space in the hermetic container 1 into communication with each other. A high pressure opening 72 of the high pressure communication path 71 is provided with a balance valve 73.
The outer peripheral wall 11c of the fixed scroll 11 is provided with a peripheral wall-side intermediate pressure communication path 42b which brings a mirror plate-side intermediate pressure communication path 42a and the intermediate pressure region B into communication with each other.
The mirror plate-side intermediate pressure communication path 42a and the peripheral wall-side intermediate pressure communication path 42b form an intermediate pressure communication path 42. The intermediate pressure communication path 42 is formed in the fixed scroll 11, and brings the intermediate pressure extraction hole 41 and the intermediate pressure region B into communication with each other.
By forming, in the fixed scroll 11, the intermediate pressure communication path 42 which brings the intermediate pressure extraction hole 41 and the intermediate pressure region B into communication with each other, and by guiding the intermediate pressure of the compression chambers 15 into the intermediate pressure region B in this manner, it is possible to prevent the orbiting scroll 12 from separating from the fixed scroll 11 and enhance the airtightness of the compression chambers 15 especially under a low compression ratio condition.
Further, especially under the low compression ratio condition, if intermediate pressure in mid-flow of compression of the compression chamber 15 becomes excessively high, intermediate pressure in mid-flow of compression of the compression chamber 15 is adjusted to predetermined pressure by opening the balance valve 73, and a compression ratio of the low compression ratio condition at which the orbiting scroll 12 separates from the fixed scroll 11 can be made small.
The orbiting scroll mirror plate 12a is provided with a first oil introduction hole 51 formed in the boss portion 12c, a first oil derivation hole 52 formed in an outer periphery of the lap-side end surface, and a first mirror plate oil communication path 53 which brings the first oil introduction hole 51 and the first oil derivation hole 52 into communication with each other.
The orbiting scroll mirror plate 12a is provided with a second oil introduction hole 61 which opens from the intermediate pressure region B, a second oil derivation hole 62 which opens from a low pressure space of the compression chambers 15, and a second mirror plate oil communication path 63 which brings the second oil introduction hole 61 and the second oil derivation hole 62 into communication with each other. The second oil introduction hole 61 is formed in a side surface of the orbiting scroll mirror plate 12a.
Figs. 3 are plane views of the fixed scroll and the orbiting scroll shown in Figs. 1 and 2.
Fig. 3(a) is a plane view of the fixed scroll of the embodiment as viewed from the fixed spiral lap, and Fig. 3(b) is a plane view of the orbiting scroll of the embodiment as viewed from the orbiting spiral lap.
In Fig. 3(a), the intermediate pressure region B is shown as a gray zone. As shown in Fig. 3(a), the intermediate pressure region B is formed in the outer periphery of the fixed spiral lap 11b. As shown in Fig. 4(a), a recess 11d is formed in a periphery of an opening leading to the intermediate pressure region B of the peripheral wall-side intermediate pressure communication path 42b.
The fixed scroll 11 is provided with a fixed scroll sliding surface 11e which slides with respect to the orbiting scroll mirror plate 12a located closer to the outer periphery than the orbiting spiral lap 12b shown in Fig. 3(b). The intermediate pressure region B is formed closer to the outer periphery than the fixed scroll sliding surface 11e.
The fixed scroll sliding surface 11e is provided with a sliding surface groove 54 which is in communication with the intermediate pressure region B.
As shown in Fig. 3(b), the first oil derivation hole 52 and the second oil derivation hole 62 open from the outer periphery of the lap-side end surface of the orbiting scroll mirror plate 12a.
Figs. 4 are explanatory diagrams showing a supplying operation of lubricant oil existing in a boss portion into the intermediate pressure region.
Fig. 4(a) is a plane view of a state where the orbiting scroll shown in Fig. 3(b) meshes with the fixed scroll shown in Fig. 3(a) . Fig. 4(b) is a plane view of the orbiting scroll and the eccentric shaft in a state shown in Fig. 4(a). Fig. 4(c) is an enlarged plane view of essential portions of Fig. 4(a).
As shown in Figs. 4, the first oil derivation hole 52 and the sliding surface groove 54 are in communication with each other in a rotation position where an eccentric shaft center C of the eccentric shaft 13a comes closest to the sliding surface groove 54.
The eccentric shaft center C of the eccentric shaft 13a rotates around a rotation shaft center D of the rotation shaft 13 like a locus E. The first oil derivation hole 52 rotates like a locus F in the same manner as the locus E of the eccentric shaft center C.
Therefore, the first oil derivation hole 52 comes into communication with the sliding surface groove 54 in the rotation position where the eccentric shaft center C of the eccentric shaft 13a comes closest to the sliding surface groove 54, and the first oil derivation hole 52 does not come into the communication in other positions.
The oil reservoir 80 is placed between the rotation shaft center D of the rotation shaft 13 and the first oil introduction hole 51. By placing the oil reservoir 80 between the rotation shaft center D of the rotation shaft 13 and the first oil introduction hole 51 in this manner, lubricant oil which flows out from the oil reservoir 80 by a centrifugal force is swiftly guided to the first oil introduction hole 51. Further, since a centrifugal force acting from the oil reservoir 80 toward the first oil introduction hole 51 is applied when the first oil derivation hole 52 comes into communication with the sliding surface groove 54, sufficient lubricant oil flows into the first mirror plate oil communication path 53.
As shown in Fig. 1, lubricant oil stored in the oil storage section 4 is introduced into the boss portion 12c through the rotation shaft oil support hole 13c. The lubricant oil introduced into the boss portion 12c is introduced into the sliding surface groove 54 through the first mirror plate oil communication path 53 as shown in Figs. 4, and the lubricant oil introduced into the sliding surface groove 54 is intermittently introduced into the intermediate pressure region B.
According to the scroll compressor of the embodiment, the high pressure region A and the intermediate pressure region B are formed, and the orbiting scroll 12 is pushed against the fixed scroll 11. Therefore, the lap-side end surface of the orbiting scroll mirror plate 12a and the fixed scroll sliding surface 11e can maintain a close contact state without separating from each other. Hence, an oil amount can be adjusted by the first oil derivation hole 52 and the sliding surface groove 54, and it is easy to adjust the oil amount.
According to the scroll compressor of the embodiment, the largest centrifugal force is applied to lubricant oil existing in the boss portion 12c in the rotation position where the eccentric shaft center C of the eccentric shaft 13a comes closest to the sliding surface groove 54. Therefore, by bringing the first oil derivation hole 52 and the sliding surface groove 54 into communication with each other when the largest centrifugal force is applied to lubricant oil existing in the boss portion 12c, it is possible to reliably introduce the lubricant oil into the sliding surface groove 54.
Figs. 5 are explanatory diagrams showing a deriving operation of lubricant oil existing in the intermediate pressure region into the compression chamber.
Fig. 5(a) is a plane view like Fig. 4(a) in which a position of the orbiting scroll is different from that shown in Fig. 4(a), and Fig. 5(b) is an enlarged plane view of essential portions of Fig. 5(a).
The second oil derivation hole 62 shown in Figs. 5 rotates like a locus G in the same manner as the locus E of the eccentric shaft center C shown in Figs. 4.
In a state shown in Figs. 5, the second oil derivation hole 62 is in communication with low pressure spaces of the compression chambers 15. Therefore, lubricant oil existing in the intermediate pressure region B is introduced from the second oil introduction hole 61, and is introduced from the second oil derivation hole 62 into the low pressure spaces of the compression chambers 15 through the second mirror plate oil communication path 63. In a state shown in the drawings other than Figs. 5, the second oil derivation hole 62 is closed by the fixed scroll sliding surface 11e. Therefore, lubricant oil existing in the intermediate pressure region B is intermittently introduced into the low pressure spaces of the compression chambers 15.
According to the scroll compressor of the embodiment, lubricant oil in the intermediate pressure region B can be circulated by introducing, into the low pressure spaces of the compression chambers 15, the lubricant oil which is introduced into the intermediate pressure region B, and it is possible to prevent oil from being deteriorated by shortage of oil supply in the intermediate pressure region B and by accumulation of lubricant oil.
Figs. 6 are explanatory diagrams showing a positional relation between a refueling pathway and the sealing member associated with orbiting motion of the scroll compressor.
Figs. 6(a) show a state where the orbiting scroll 12 is meshed with the fixed scroll 11 and this is viewed from a back surface of the orbiting scroll 12. Fig. 6(b) shows a state where Fig. 6(a) rotates 90 degrees, Fig. 6(c) shows a state where Fig. 6(b) further rotates 90 degrees, and Fig. 6(d) shows a state where Fig. 6(c) further rotates 90 degrees.
As the compression chambers 15 formed by the fixed scroll 11 and the orbiting scroll 12, a first compression chamber 15A is formed on the side of an outer wall of the orbiting spiral lap 12b, and a second compression chamber 15B is formed on the side of an inner wall of the orbiting spiral lap 12b.
As shown in Figs. 6, by elongating an outer peripheral end 11be of the fixed spiral lap 11b to the same length as an outer peripheral end 12be of the orbiting spiral lap 12b in the state where the fixed scroll 11 and the orbiting scroll 12 mesh with each other, a position where refrigerant in the first compression chambers 15A is trapped and a position where refrigerant in the second compression chambers 15B is trapped are deviated about 180 degrees from each other.
Fig. 6(a) shows a position where the refrigerant in the first compression chambers 15A is trapped, and Fig. 6(c) shows a position where refrigerant in the second compression chambers 15B is trapped.
In the state shown in Fig. 6(a), three first compression chambers 15A (15A1, 15A2 and 15A3) are formed, the first compression chamber 15A1 located on an outermost periphery is in a low pressure state immediately after refrigerant is trapped, the first compression chamber 15A2 formed on the more inner peripheral side than the first compression chamber 15A1 is in an intermediate pressure state, and the first compression chamber 15A3 formed on the more inner peripheral side than the first compression chamber 15A2 is in a high pressure state before discharge. In Fig. 6(a), symbols of the second compression chambers 15B are omitted.
In the state shown in Fig. 6(c), three second compression chambers 15B (15B1, 15B2 and 15B3) are formed, the second compression chamber 15B1 located on the outermost periphery is in a low pressure state immediately after refrigerant is trapped, the second compression chamber 15B2 formed on the more inner peripheral side than the second compression chamber 15B1 is in an intermediate pressure state, and the second compression chamber 15B3 formed on the more inner peripheral side than the second compression chamber 15B2 is in a high pressure state which is a discharge state.
The first compression chamber 15A1 shown in Fig. 6(a) has a suction volume of the first compression chamber 15A, and the second compression chamber 15B1 shown in Fig. 6(c) has a suction volume of the second compression chamber 15B. By deviating a position where refrigerant in the first compression chamber 15A is trapped and a position where refrigerant in the second compression chamber 15B is trapped from each other 180 degrees, the suction volume of the first compression chamber 15A is made larger than that of the second compression chamber 15B.
The intermediate pressure extraction hole 41 opens from the first compression chamber 15A2 which is in the intermediate pressure state as shown in Fig. 6(a), and opens from the second compression chamber 15B2 which is in the intermediate pressure state as shown in Fig. 6(c). By placing the intermediate pressure extraction hole 41 at a center between pitches of the fixed spiral lap 11b which is in the intermediate pressure state, it is possible to uniformly open the intermediate pressure extraction hole 41 from the first compression chamber 15A2 which is in the intermediate pressure state and from the second compression chamber 15B2 which is in the intermediate pressure state.
The second oil derivation hole 62 opens from the first compression chamber 15A1 which is in the low pressure state at a position shown in Fig. 6(b).
As shown in Figs. 6, since a suction volume can be made maximum by deviating closing timings of refrigerant between the first compression chamber 15A and the second compression chamber 15B about 180 degrees, it is possible to set a lap height low.
Fig. 7 is a graph showing pressure variation of intermediate pressure which is taken out from the intermediate pressure extraction hole in the scroll compressor of the embodiment. Figs. 8 and 9 are graphs showing pressure variation of intermediate pressure which is taken out from the intermediate pressure extraction hole in a scroll compressor as a comparative example.
That is, Fig. 7 shows a pressure variation width of intermediate pressure which is taken out from the intermediate pressure extraction hole when the fixed scroll is provided with an intermediate pressure communication path in an asymmetric scroll compressor in which a suction volume of a first compression chamber and a suction volume of a second compression chamber are different from each other.
Fig. 8 shows a pressure variation width of intermediate pressure which is taken out from the intermediate pressure extraction hole when the fixed scroll is provided with an intermediate pressure communication path in an asymmetric scroll compressor in which the suction volume of the first compression chamber and the suction volume of the second compression chamber are different from each other.
Fig. 9 shows a pressure variation width of intermediate pressure which is taken out from the intermediate pressure extraction hole when the fixed scroll or the orbiting scroll is provided with the intermediate pressure communication path in a symmetric scroll compressor in which the suction volume of the first compression chamber and the suction volume of the second compression chamber are the same.
In Figs. 7 to 9, a horizontal axis shows a crank angle, and a vertical axis shows pressure in the compression chamber.
In the drawings, a curve H shows pressure variation of the first compression chamber, and a curve J shows pressure variation of the second compression chamber.
As shown in Fig. 7, by providing the fixed scroll with the intermediate pressure extraction hole in the asymmetric scroll compressor in which the suction volume of the first compression chamber and the suction volume of the second compression chamber are different from each other, it is possible to make, small, a pressure variation width of intermediate pressure which is taken out from the intermediate pressure extraction hole as compared with a case where the orbiting scroll is provided with the intermediate pressure extraction hole in the asymmetric scroll compressor shown in Fig. 8, and as compared with a case where the orbiting scroll or the fixed scroll is provided with the intermediate pressure extraction hole in the symmetric scroll compressor shown in Fig. 9. Therefore, pulsation in an intermediate pressure region can be made small, and it is possible to push the orbiting scroll against the fixed scroll stably.
As the refrigerant of the present invention, it is possible to use R32, carbon dioxide, and refrigerant having carbon-carbon double bond.

[INDUSTRIAL APPLICABILITY]

The scroll compressor of the present invention is useful for a refrigeration cycle device of a hot water heater, an air conditioner, a hot water supplying system, a freezing machine and the like.

[EXPLANATION OF SYMBOLS]

1: hermetic container
2: refrigerant suction pipe
3: refrigerant discharge pipe
4: oil storage section
5: oil pump
6: discharge chamber
10: compressing mechanism
11: fixed scroll
12: orbiting scroll
13: rotation shaft
13a: eccentric shaft
13b: lower end
13c: rotation shaft oil support hole
13d: orbiting bearing
13e: oil groove
14: discharge port
15: compression chamber
15A: first compression chamber
15B: second compression chamber
16: bolt
17: rotation restraining member
18: auxiliary bearing
20: electric mechanism
21: stator
22: rotor
30: main bearing
31: bearing
32: boss storing section
41: intermediate pressure extraction hole
42: intermediate pressure communication path
51: first oil introduction hole
52: first oil derivation hole
53: first mirror plate oil communication path
61: second oil introduction hole
62: second oil derivation hole
63: second mirror plate oil communication path
71: high pressure communication path
72: high pressure opening
73: balance valve
80: oil reservoir

Claims

A scroll compressor in which
a compressing mechanism (10) for compressing refrigerant and an electric mechanism (20) for driving the compressing mechanism (10) are placed in a hermetic container (1),

an oil storage section (4) for storing lubricant oil therein is formed in a bottom of the hermetic container (1),

the compressing mechanism (10) includes a fixed scroll (11), an orbiting scroll (12) and a vertical rotation shaft (13) for driving the orbiting scroll (12) in an orbiting manner,

the fixed scroll (11) includes a disk-like fixed scroll mirror plate (11a) and a fixed spiral lap (11b) standing on the fixed scroll mirror plate (11a),

the orbiting scroll (12) includes a disk-like orbiting scroll mirror plate (12a), an orbiting spiral lap (12b) standing on a lap-side end surface of the orbiting scroll mirror plate (12a), and a boss portion (12c) formed on an opposite side from the lap-side end surface of the orbiting scroll mirror plate (12a),

an eccentric shaft (13a) inserted into the boss portion (12c) is formed on an upper end of the rotation shaft (13),

the fixed spiral lap (11b) and the orbiting spiral lap (12b) are meshed with each other, and a plurality of compression chambers (15) are formed between the fixed spiral lap (11b) and the orbiting spiral lap (12b),

a main bearing (30) for supporting the fixed scroll (11) and the orbiting scroll (12) is provided below the fixed scroll (11) and the orbiting scroll (12),

a bearing (31) for pivotally supporting the rotation shaft (13) and a boss storing section (32) for storing the boss portion (12c) therein are formed in the main bearing (30),

a rotation restraining member (17) for restraining rotation of the orbiting scroll (12) is provided between the fixed scroll (11) and the main bearing (30),

a rotation shaft oil support hole (13c) extending from a lower end (13b) of the rotation shaft (13) to the eccentric shaft (13a) is formed in the rotation shaft (13), and

the orbiting scroll mirror plate (12a) is provided with a first oil introduction hole (51) formed in the boss portion (12c), a first oil derivation hole (52) formed in an outer periphery of the lap-side end surface, and a first mirror plate oil communication path (53) for bringing the first oil introduction hole (51) and the first oil derivation hole (52) into communication with each other, wherein

an oil reservoir (80) is formed in an upper surface of the eccentric shaft (13a), and

the oil reservoir (80) is placed radially outwards from a rotation shaft center of the rotation shaft (13) but radially inwards of the first oil introduction hole (51), with respect to the rotation shaft centre of the rotation shaft (13),
characterized in that
the boss storing section (32) is a high pressure region, an outer periphery of the orbiting scroll (12) where the rotation restraining member (17) is placed is an intermediate pressure region, communicating with an intermediate pressure extraction hole (41) in the compression chamber (15), and the orbiting scroll (12) is pushed against the fixed scroll (11),

the fixed scroll (11) is provided with a fixed scroll sliding surface (11e) which slides with respect to the orbiting scroll mirror plate (12a) located closer to an outer periphery of the orbiting spiral lap (12b) than the orbiting spiral lap (12b),

the intermediate pressure region is formed on a location closer to the outer periphery of the orbiting spiral lap (12b) than the fixed scroll sliding surface (11e),

the fixed scroll sliding surface (11e) is provided with a sliding surface groove (54) which is in communication with the intermediate pressure region,

the lubricant oil stored in the oil storage section (4) is introduced into the boss portion (12c) through the rotation shaft oil support hole (13c),

the lubricant oil introduced into the boss portion (12c) is introduced into the sliding surface groove (54) through the first mirror plate oil communication path (53), and

the lubricant oil introduced into the sliding surface groove (54) is introduced into the intermediate pressure region.
The scroll compressor according to claim 1, wherein
the first oil derivation hole (52) and the sliding surface groove (54) are brought into communication with each other at a rotation position where an eccentric shaft center of the eccentric shaft (13a) comes closest to the sliding surface groove.
The scroll compressor according to claim 1 or 2, wherein
as the compression chamber (15), a first compression chamber (15A) is formed on an outer wall side of the orbiting spiral lap (12b), and a second compression chamber (15B) is formed on an inner wall side of the orbiting spiral lap (12b),

a suction volume of the first compression chamber (15A) is made larger than a suction volume of the second compression chamber (15B),

the fixed scroll mirror plate (11a) is provided with an intermediate pressure extraction hole (41) through which intermediate pressure of the compression chamber (15) is taken out, and

an intermediate pressure communication path (42) for bringing the intermediate pressure extraction hole (41) and the intermediate pressure region into communication with each other is formed in the fixed scroll (11).
The scroll compressor according to claim 3, wherein
a high pressure communication path (71) for bringing the intermediate pressure extraction hole (41) and a high pressure space in the hermetic container (1) into communication with each other is formed in the fixed scroll (11), and

a balance valve (73) is provided in a high pressure opening (72) of the high pressure communication path (71).
The scroll compressor according to any one of claims 2 to 4, wherein
the orbiting scroll mirror plate (12a) is provided with a second oil introduction hole (61) which opens from the intermediate pressure region, a second oil derivation hole (62) which opens from a low pressure space of the compression chamber (15) and a second mirror plate oil communication path (63) for bringing the second oil introduction hole (61) and the second oil derivation hole (62) into communication with each other, and

the lubricant oil introduced into the intermediate pressure region is introduced in to the low pressure space of the compression chamber (15) through the second mirror plate oil communication path (63).