JP3039375B2 - Gas compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential pressure oil supply passage of a gas compressor and a separating means for separating lubricating oil mixed into discharge gas.

[0002]

2. Description of the Related Art In a scroll compressor having low vibration and low noise characteristics, a suction chamber is provided at the outer periphery of a spiral compression chamber formed by a combination of a fixed scroll and an orbiting scroll.
A discharge port is provided at the center of the spiral, and the flow of the compressed fluid is unidirectional, eliminating the need for a discharge valve to compress the fluid, such as a reciprocating compressor or rotary compressor. If there is no large fluctuation in the operating compression ratio determined by the formula, the discharge pulsation is small and a large discharge space is required by setting the volume ratio determined by the suction volume of the compression chamber and the final compression chamber volume to an appropriate value. Therefore, research on practical application of utilization development in various fields has been conducted.

However, since there are many seal portions in the compression chamber, there is a lot of leakage of the compressed fluid. Particularly, in the case of a scroll gas compressor having a small displacement capacity such as a refrigerant compressor for home air conditioning,
In order to reduce the leakage gap of the compression part, it is necessary to make the dimensional accuracy of the spiral part extremely high.

[0004] However, due to the complexity of the shape of parts, the cost of the scroll gas compressor is high and the performance varies greatly due to variations in dimensional accuracy of the spiral part. It has the disadvantages of high leakage rate and lower compression efficiency than reciprocating compressors and rotary compressors.

Therefore, as measures for solving this type of problem, in order to prevent gas leakage during compression, the accuracy of the combination of the spiral portions of the two scrolls, the setting of the eccentricity of the crank mechanism of the drive shaft, and the optimization of the bearing clearance are set. As described in Japanese Patent Application Laid-Open No. 57-8386, an appropriate amount of lubricating oil is injected into a compression chamber in the middle of compression, and an oil film sealing action utilizing lubricating oil is performed. Means for improving the compression efficiency by the compression chamber gap sealing effect have been proposed.

In particular, scroll refrigerant compressors have been put into practical use in the field of refrigeration and air conditioning, and various types of medium to large class compressors, such as packaged air conditioners and chiller units, having a relatively large refrigerant volume per one suction stroke have been developed. Improvements have been made and mass production has already been realized.

FIG. 16 shows an example of a general structure of a medium to large class scroll refrigerant compressor having a high-pressure space in a closed case (chamber). In the figure, the compression unit and the discharge chamber 1031 are at the top, the motor (electric element) is at the bottom,
An oil sump is provided at the bottom at the discharge pipe 104 which is the final outlet of the compressor.
2 is disposed in the vicinity of the motor (electric element), and after the discharge refrigerant gas and the lubricating oil are separated in the discharge chamber 1031, the lubricating oil is stored in the motor (electric element) through oil drain holes 1035 and 1036. Returning to the space, the refrigerant gas is collected in the oil reservoir at the bottom, and the discharged refrigerant gas is discharged from the discharge pipe 1042 again after passing through the space accommodating the motor (electric element) from the upper part of the discharge chamber 1031 through another passage. You. In addition, in order to reduce the axial gap of the compression chamber, lubricating oil on which the discharge pressure acts on the bottom of the closed case (chamber) 1013 is provided inside a drive shaft (crankshaft) 1008 with an oil-lifting hole 1019 and a drive shaft ( Crankshaft) 1
After lubricating the bearing sliding surface through the clearance of the bearing of the body frame (frame) 1009 supporting the 008 and fixing the fixed scroll 1003, and the clearance of the crankshaft of the drive shaft (crankshaft) 1008, the orbiting scroll 1
The intermediate pressure lubricating oil, which has been reduced in the middle of the path, flows into the back pressure chamber 1025 provided on the rear surface of the orbit 006. Energize. As a result, the back pressure biasing force is set so as not to separate the orbiting scroll 1006 from the fixed scroll against the compression chamber gas pressure.

The lubricating oil in the back pressure chamber 1025 is supplied to a back pressure hole 1017 provided in the end plate 1004 of the orbiting scroll 1006.
After flowing into the compression chamber 1015 in the middle of compression, the compressed gas is compressed / discharged together with the suctioned refrigerant gas while sealing the gap of the compression chamber 1015 and discharged to the discharge chamber 1031. The shape of the drive shaft (crankshaft) 1008 is disclosed in
-60092 is different from a mode in which the outer diameter of the shaft at the tip of the drive shaft is increased and the shaft portion of the orbiting scroll is slidably engaged with the eccentric hole provided in the portion,
A configuration in which a crankshaft portion is provided at the tip of a drive shaft (crankshaft) 1008 to reduce bearing sliding resistance by reducing the diameter of a bearing portion that supports the drive shaft (crankshaft) 1008. (JP-A-56-165788).

[0009]

However, the configuration as shown in FIG. 16 has a problem relating to the differential pressure lubrication described below.

That is, the first problem is that a large amount of refrigerant gas is mixed in the lubricating oil supplied from the oil reservoir to the compression chamber 1015 through the back pressure chamber 1025, so that an oil film is formed by the lubricating oil. Although the compression chamber gap is sealed by this, the compressed refrigerant gas re-flows into the compression chamber 1015, resulting in a decrease in compression efficiency.

On the other hand, when the amount of oil supply from the oil reservoir to the compression chamber 1015 is reduced in order to reduce the re-inflow amount of the compressed refrigerant gas into the compression chamber 1015, the bearing sliding of the drive shaft (crankshaft) 1008 is performed. This causes a shortage of refueling to the department, and it is not possible to solve both at the same time.

The second problem is that due to the residual pressure difference between the oil reservoir and the compression chamber 1015 immediately after the compressor is stopped, the lubricating oil in the oil reservoir continues to flow into the compression chamber 1015, and as a result, the compressor is restarted. At this time, a shortage of lubricating oil in the oil reservoir and an excessive load due to oil compression in the compression chamber 1015 may cause serious accidents such as a failure to restart, a remarkable decrease in bearing durability and breakage.

On the other hand, as a measure for solving the above-mentioned second problem, an oil supply means proposed by the inventor in Japanese Patent Application Laid-Open No. 1-177482, that is, an oil sump (discharge chamber oil sump 34) of a scroll gas compressor. ) Via the drive shaft and the bearing sliding portion of the orbiting scroll (eccentric bearing 14), etc.
Branching from the middle of the differential pressure oil supply passage to the compression chamber 51b),
A means for supplying oil to a spiral oil groove (41) provided on the bearing sliding surface of the drive shaft whose end is not opened, and Japanese Patent Application Laid-Open Nos. 51-23239, 59-2995, and 1-163.
As disclosed in Japanese Patent No. 493, the lubricating oil supplied to the compression chamber is formed by combining a helical oil groove provided on the sliding surface of the drive shaft with an oil supply means opened to a space for accommodating the motor. A configuration in which mixed gas is vented can be considered.

However, if the amount of oil supplied to the eccentric bearing 14 and the like is increased in order to reduce the bearing friction loss and improve the durability of the bearing, the amount of oil supplied to the compression chamber is increased, so that the overheating of the compression chamber and the oil compression are increased. As a result of lowering the compression efficiency, there is a problem that the first and second problems cannot be simultaneously solved.

The present invention has been made to solve the above-mentioned conventional problems, and provides sufficient lubrication to a sliding portion of a bearing relating to a drive shaft, supply of a proper amount of lubricating oil degassed to a compression chamber, and stop of a compressor. It is an object of the present invention to provide a scroll gas compressor that can block unnecessary inflow of lubricating oil into a compression chamber immediately after.

[0016]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a bearing in a lubricating oil circulation pump path which passes through a bearing for supporting an oil reservoir and a drive shaft and a motor chamber for accommodating a motor. Part of the oil supply passage also serves as a bypass passage through which the gas in the differential pressure oil supply passage to the suction / compression space can be vented. Due to the configuration of the bypass passage, the amount of discharge gas contained in the lubricating oil flowing into the compression chamber can be reduced.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention , lubricating oil in a discharge chamber oil reservoir is supplied to a bearing sliding surface of a drive shaft using a pump means, and then returned to the discharge chamber oil reservoir via a motor chamber. While providing a circulation pump path of the bearing oil supply passage to be made, a part of the bearing oil supply passage also serves as a passage to the branch point where the lubricating oil from the discharge chamber oil reservoir in the differential pressure oil supply passage goes to the suction / compression space.
The remaining passage is branched off from the middle of the differential pressure oil supply passage, and also serves as a bypass passage of the differential pressure oil supply passage that allows gas to flow from the motor chamber to the intermediate position of the differential pressure oil supply passage only when the compressor is stopped. Things. According to this configuration, sufficient lubrication to the bearing sliding surface of the drive shaft and the amount of discharge gas inflow due to lubrication to the compression chamber are reduced, thereby reducing sliding friction loss and lowering compression efficiency.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A scroll refrigerant compressor according to an embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1) In FIG. 1, reference numeral 801 denotes a closed case made of iron, in which a fixed scroll 815 which meshes with a revolving scroll 818 to form a compression chamber is fixed by bolts, and a drive shaft 704 is provided.
Are partitioned into an upper motor chamber 806 and a lower accumulator chamber 846 by a main body frame 805 that supports.

The motor chamber 846 has a high-pressure atmosphere. A motor 703 is provided at an upper part, and a compression part is provided at a lower part. A main body frame 805 supporting a driving shaft 704 to which a rotor 703a of the motor 703 is connected and fixed has a sliding characteristic and a welding characteristic. Made of eutectic graphite cast iron having excellent heat resistance, and a protrusion 879 provided on the outer peripheral surface thereof.
a is an upper sealed case 801a and a lower sealed case 801b
Abuts on the inner wall surface and the end surface of the protrusion 879a.
, Upper sealed case 801a and lower sealed case 801b are hermetically welded by a single welding bead 879b.

The upper sealed case 801a is composed of a body shell 801a1 for supporting the stator 703b of the motor 703 and an upper shell 801a2 on which a glass terminal 88 as a motor power supply connection terminal is disposed.
An upper frame 126 (hereinafter, referred to as a frame) supporting one end of the upper frame 4 is disposed.

Discharge pipe 831 and glass terminal 88
12 separating the side of the motor and the side of the motor 703
Numeral 6 is made of gray cast iron, and a protrusion 779a on the outer periphery thereof is provided.
Are the inner walls of the upper shell 801a2 and the torso shell 801a1,
And a single weld bead 779b abutting the end face.
Are sealingly fixed to the upper shell 801a2 and the body shell 801a1, and are fixed by sandwiching the outer peripheral portion of the projecting portion 779a of the frame 126. In other words, the weld bead 779b is composed of the upper shell 801a2 and the shell 8 made of soft iron.
No. 01a1, the weld bead 779b surrounds the frame 126 without forming an alloy structure with the surface of the gray cast iron frame 126 and without affecting welding distortion. It is fixed.

The oil separation chamber 128a provided at the upper part of the frame 126 is provided with a gas hole 129 provided at the frame 126.
Through the motor chamber 706.

Drive shaft 704 supported on frame 126
The surface of the upper end shaft 704d has a spiral oil groove 741d in a direction in which the lubricating oil separated from the discharge gas in the oil separation chamber 128a is guided to the motor chamber 806 when the drive shaft 704 rotates forward.
Is provided.

An upper balance weight 775 and a lower balance weight 776 are attached to the upper end and lower end of the rotor 703a of the motor 703, and the axial movement of the rotor 703a causes the end of the frame 126 and the end of the body frame 805 to move in the axial direction. Are regulated between.

The diameter D of the main bearing 812 of the drive shaft 704 supported by the frame 126 and the body frame 805 is set to be larger than the sum of the diameter d of the crankshaft 714 and twice the crank eccentricity (e). The drive shaft 704 can be pulled out in the upper direction.

The lower surface of the lower balance weight 776 is in contact with the thrust bearing 713 at the upper end of the main body frame 805 to support the drive shaft 704 and the rotor 703a.

The oil sump 772 above the main bearing 812 is connected to the back pressure chamber 83 of the orbiting scroll 718 through an oil hole B 738b.
It leads to 9.

The high-pressure oil chamber A778a is
5 through the oil hole A838a provided in the discharge chamber 34.
Leads to.

The discharge chamber 2 communicating with the discharge port 16 of the compression chamber
Communicates with the motor chamber 806 via a discharge passage 880 described later.

The discharge passage 880 (see FIG. 1) is provided in the discharge chamber 2 and the fixed scroll 815 formed by the discharge cover 2a mounted on the end plate 815b and the end plate 815b so as to cover the check valve device 50. Gas passage B88
0b, gas passage A88 provided in main body frame 805
0a, the discharge guide 881 attached to the main body frame 805 so as to surround the main bearing 812, and the main body frame 805.
The gas passage A 880a and the gas passage B 880b are provided at symmetrical positions, respectively (see FIG. 12).

As shown in FIG. 7, a large number of small holes 81a are provided on the upper surface of the discharge guide 881.

An accumulator chamber 846 communicating with the evaporator side of the refrigeration cycle is formed by a lower sealed case 801b, a fixed scroll 815, and a main body frame 805, and a suction pipe 47 communicating therewith is provided on a side surface of the lower sealed case 801b. The suction holes 43 are provided in the fixed scroll 815 at two positions separated from each other by approximately 90 degrees from the position facing the suction pipe 47 (see FIG. 12).

Oil hole A8 provided in main body frame 805
Oil chamber A778a which communicates with the discharge chamber oil reservoir 34 via 38a
The orbiting scroll 8 is provided by an annular ring 94 attached to the end of the orbiting boss 818e of the orbiting scroll 818.
Excessive leakage of lubricating oil into the back pressure chamber 839 of the lubricating oil supply 18 is prevented.

As shown in FIGS. 1 and 8, the oil chamber A 778a
Communicates with the discharge chamber oil reservoir 34 via an oil hole A838a provided in the main body frame 805.

The orbiting boss 818 of the orbiting scroll 818
An annular seal groove 955 concentric with the center of the slewing bearing 818b is provided on the end face of the body frame 805 on the side of the main body 805, and a part of the annular seal groove 95 is cut as shown in FIG. And an annular ring 94 made of resin having flexibility. The outer peripheral surface of the annular ring 94 has an annular seal groove 95 due to the thermal expansion of the annular ring 94 and the lubricating oil pressure inside the annular ring 94 during operation of the compressor.
And a cutout 94b having an inclination angle with respect to the outer peripheral surface of the annular ring 94 is arranged so as to be in close contact with each other. The annular ring 94 extends from the oil chamber A 778 a on the side of the main bearing 812 supporting the drive shaft 704 to the orbiting scroll 818, the main body frame 805, and the thrust bearing 220.
Back pressure chamber 83 of orbiting scroll 818 formed by
9 is sealed to prevent excessive leakage.

The oil chamber A 778a is provided with a helical oil groove 741b provided on the outer peripheral surface of the crankshaft 714 and the crankshaft 71.
4, an oil chamber B 778 b provided at an end portion, an axial oil hole 112 d provided in the drive shaft 704, and a spiral oil groove 74.
1a, an oil sump 772, and an oil hole B738b provided in the main body frame 705, and communicates with the back pressure chamber 739.
The open end of the oil hole B738b is intermittently shut off by the turning motion of the annular ring 94.

The fixed scroll 815 is made of a high silicon aluminum alloy whose coefficient of thermal expansion is equivalent to an intermediate value between pure aluminum and eutectic graphite cast iron, and has a spiral fixed scroll wrap 815a as shown in FIG. At the center of the end plate 815b, a discharge port 16 that opens at the beginning of winding of the fixed scroll wrap 515a is provided in communication with a discharge passage 880 that opens to the motor chamber 806, and an outer peripheral portion of the fixed scroll wrap 815a is provided. Is provided with a suction chamber 17.

A check valve device 50 is mounted on the end plate 815b on the side opposite to the orbiting scroll so as to cover the discharge port 16, and the check valve device 50 is, as described in detail in FIGS. A valve body 50b (or a valve body 50e having a discontinuous annular hole 50ea) made of a thin steel plate having a shape in which the outer peripheral portion is cut off at several places, a check valve hole 50a and a central hole 50g.
And a valve case 9 having a plurality of small discharge holes 50h therearound.
9 and a spring device 50c interposed between the valve body 50b and the valve case 99. The spring device 50c contracts when its own temperature exceeds 50 ° C., and its own temperature becomes 50 ° C.
The compressor has a shape memory characteristic that expands at a temperature of 50 ° C. or less, and contracts to the bottom surface of the check valve hole 50a due to the discharged refrigerant gas pressure during operation of the compressor, and the temperature of the compressor itself is 50 ° C. or less. During stop, the valve body 50 is set to be pressed against the end plate 15b so as to close the discharge port 16.

As shown in FIGS. 1 and 12, a spiral orbiting scroll wrap 818a meshing with the fixed scroll wrap 815a to form a side wall of the compression chamber,
Turning boss 818e engaged with the crankshaft 714 of No. 04
The orbiting scroll 818 made of an aluminum alloy, which is composed of a wrap support disk 818c in which the uprights are upright, is disposed so as to be surrounded by the fixed scroll 815 and the main body frame 805. The surfaces of the wrap support disk 818c and the orbiting scroll wrap 818a are porous. Hardening treatment such as high quality nickel plating is performed. As shown in FIG. 3, a spiral tip seal groove 9 is provided at the tip of the orbiting scroll wrap 818a.
A resin chip seal 98a is mounted in the chip seal groove 98 with a minute gap. When the orbiting scroll 818 is pressed in the axial direction of the fixed scroll 815, the flat portion of the wrap support disk 818 c contacts the tip of the fixed scroll wrap 815 a, but the tip of the orbiting scroll wrap 818 a does not contact the fixed scroll 815. A minute distance of about a micron is maintained.

The low pressure oil reservoir 846a at the bottom of the accumulator chamber 846 and the suction hole 43 communicate with an oil suction hole A9a provided on the discharge cover 2a and a small-diameter oil suction hole B9b provided on the fixed scroll 815. These oil suction holes (9a, 9b) are set so that refrigerant liquid or lubricating oil accumulated in the low-pressure oil reservoir 846a is sucked up by generation of negative pressure when refrigerant gas passes through the suction holes 43. I have.

A plate-shaped thrust bearing 22 which is restricted in movement in the rotational direction by a split pin-shaped parallel pin 19 fixed to the main body frame 805 and is movable only in the axial direction.
Numeral 0 denotes an elastic force of an annular seal ring (made of rubber) 70 (see FIG. 10) disposed between the lap support disk 818c and the main body frame 805 and interposed between the thrust bearing 220 and the main body frame 805. As a result, it comes into contact with the end plate mounting surface 15b1 between the main body frame 805 and the fixed scroll 815.

Wrap support disk 8 for orbiting scroll 818
The height from the sliding face 15b2 of the end plate slidingly in contact with the end plate 18c to the mounting surface 15b1 of the end plate 18c is determined by the oil film of the lap supporting disk 818c so as to improve the sealing performance of the sliding part.
The thickness is set to be approximately 0.015 to 0.020 mm larger than the thickness of 18c.

The annular thrust bearing 220 is made of a sintered alloy whose hole can be easily formed. As shown in FIGS. 10 and 11, two guide holes 93 into which the split pin 19 is movably inserted, an annular oil groove 92, and oil It has a hole 91 and is attached to the thrust ring groove 890 of the main body frame 805.

Body frame 805 and thrust bearing 220
A release gap 827 of about 0.05 mm is provided between the two, and an annular groove 28 for mounting the seal ring 70 is provided inside and outside the release gap 827. The seal ring 70 seals between the release gap 827 and the back pressure chamber 839.

A plurality of coil springs 131 are arranged at equal intervals on the back side of the thrust bearing 220 on the opposite side of the compression chamber, and the end faces of the coil springs 131 are held down by a discharge guide 881 attached to the main body frame 805, so that the thrust bearings are thrust. The bearing 220 is fixed to the end plate 815 of the fixed scroll 815.
b.

The rear side of the thrust bearing 220 communicates with the discharge chamber oil reservoir 34 through a coil spring mounting hole 132 provided in the main body frame 805 and an oil introduction hole 133 provided in the discharge guide 881.

On the back side of the thrust bearing 220, a seal ring A70a is mounted only on the inner side, and on the outer side,
The thrust bearing 220 is sealed by pressing against the end plate 815b.

As shown in FIGS. 1 and 2, the thrust bearing 2
The rotation preventing member (hereinafter referred to as Oldham ring) 24 of the orbiting scroll 818 disposed inside 20 is made of a light alloy or a reinforced fiber composite material suitable for sinter molding, injection molding or the like. A key portion having a parallel key shape orthogonal to each other on both surfaces is provided. The key portion on the upper surface is provided in a key groove 71a provided in the main body frame 805, and the key portion on the lower surface is provided in a lap support disk 818c. It engages with the groove 71 and slides.

The thickness of the ring of the Oldham ring 24 is such that when the Oldham ring 24 reciprocates, the
5 and the lap support disk 818c are set so as to slide smoothly and no jumping phenomenon occurs.

As shown in FIGS. 1, 10 and 12, the back pressure chamber 839 is provided with the first compression chamber 6 intermittently communicating with the suction chamber 17.
1a and 61b are approximately 180 degrees before the suction refrigerant gas is completely confined.
The oil groove 291 provided on the thrust bearing 220, the outer peripheral space 37 outside the lap support disk 818c, and the oil groove 89 provided on the sliding surface of the end plate 815b within the turning angle range of degrees.
1 through the suction chamber 17.

In FIG. 13, the horizontal axis represents the rotation angle of the drive shaft 704, the vertical axis represents the refrigerant pressure, the pressure change state of the refrigerant gas during the suction, compression, and discharge processes.
2 indicates a pressure change during operation at normal pressure, and a dotted line 63 indicates a pressure change during abnormal pressure rise.

The operation of the scroll refrigerant compressor configured as described above will be described.

1 to 13, when the drive shaft 704 is driven to rotate by the motor 703, the orbiting scroll 8 is rotated.
The drive shaft 7 is driven by a crank mechanism of the drive shaft 704.
The key section on the side of the orbiting scroll 818 of the Oldham ring 24 is about to rotate around the main axis of the 04 (see FIG. 2).
Is engaged with the key groove 71 of the orbiting scroll 818, and the key portion on the opposite side is engaged with the key groove 71a (see FIG. 1) of the main body frame 805. Along with 815, the volume of the compression chamber is changed to perform a suction / compression operation of the refrigerant gas.

The release gap 27 on the back side of the thrust bearing 20 communicating with the discharge chamber oil reservoir 34 communicating with the discharge port 16 of the compression chamber is filled with lubricating oil on which the pressure of the discharged refrigerant gas acts.

The thrust bearing 20 is pressed against the end plate mounting surface 815b1 of the fixed scroll 815 by the high-pressure lubricating oil, the coil spring 131, and the elastic force of the seal ring 70 as time elapses after the start of compression. As a result, the lap support disk 818c of the orbiting scroll 818 is held between the end plate sliding surface 815b2 and the thrust bearing 220 (15).
~ 20 microns assembly gap).

Then, from the refrigerating cycle connected to the compressor, the suction refrigerant of the gas-liquid mixture containing the lubricating oil flows into the accumulator chamber 846 from the suction pipe 47 and collides with the outer surface of the end plate 815b of the fixed scroll 815 after the collision. The air flows into the suction chamber 17 through two suction holes 43 (see FIG. 12) via the space above the accumulator chamber 846.

On the other hand, the liquid refrigerant and the lubricating oil separated from the refrigerant gas by the weight difference between the gas and the liquid and the inertia force at the time of changing the inflow direction are once collected at the bottom of the accumulator chamber 846, and the suction refrigerant gas is collected in the suction hole 43. Is sucked up into the suction hole 43 in an atomized state through the oil suction holes A9a and B9b by the negative pressure generated when passing through the suction port A9a and the oil suction hole B9b, and again mixed into the suction refrigerant gas.

The gas-liquid separated suction refrigerant gas is supplied to the suction chamber 1
7. Enclosed in the compression chamber via the first compression chambers 61a and 61b (see FIG. 12) formed between the orbiting scroll 818 and the fixed scroll 815, the second compression chamber 51
a, 51b and the third compression chambers 60a, 60b are sequentially transferred and compressed, and then discharged from the central discharge port 16 to the check valve chamber 50a, and are discharged to the discharge chamber 2, the gas passage B80b, and the gas passage A8.
0a and the motor chamber 80 sequentially through the discharge chamber 2b.
6 is discharged.

Immediately after the completion of compression, the third compression chamber 60a,
When the discharge port 16 is opened, the compressed refrigerant gas flows from the third compression chambers 60a and 60b to the check valve chamber 5.
0a, a rapid primary expansion occurs, and immediately after that, between the discharge completion stroke and the compression start stroke, the check valve chamber 50
a is temporarily discharged to the third compression chambers 60a, 60b.
Backflow to

As a result, the refrigerant gas intermittently flows out of the third compression chamber (60a, 60b).
a, 60b), while flowing out from the third compression chamber (60a, 60b) to the discharge chamber 2 as a whole flow, the refrigerant gas discharged from the check valve chamber 50a and the discharge chamber 2 is the third flow. Pressure fluctuations occur during the inflow and outflow to and from the compression chambers (60a, 60b), causing a pulsation phenomenon.

The discharged refrigerant gas undergoes secondary expansion when flowing toward the spherical wall surface forming the discharge chamber 2 through the small discharge hole 50h of the check valve device 50, and further collides with the spherical wall surface. Distribute evenly. Thereafter, the two discharge passages 880 disposed at the symmetrical positions are merged in the discharge chamber 2c and the motor chamber 806, so that the pulsation of the discharge gas from each discharge passage 880 is attenuated. Due to the fourth expansion, the motor chamber 806 further attenuates sequentially.
Pressure pulsation becomes extremely small.

When the discharged refrigerant gas flows backward from the discharge chamber 2 to the check valve chamber 50a instantaneously, the valve body 50b follows the flow and moves in a direction to close the discharge port 16, but the compression is not performed. During the operation of the machine, the coil spring 50c having the shape memory characteristic is fully contracted by the ambient temperature, and the urging to the valve body 50b is released, so that the discharge port 16 is not blocked by the valve body 50b.

The refrigerant gas discharged from the small holes 81a of the discharge guide 881 and discharged into the motor chamber 806 collides with the annular closing plate 86 and the windings of the motor 703, and thereafter, the cooling passage 35 on the outer side of the stator 703b. The fluid flows to the upper side of the motor chamber 806 while cooling the motor 703 through the passage inside and inside, and is sent from the discharge pipe 831 to an external refrigeration cycle.

The lubricating oil mixed with the discharged refrigerant gas from the motor chamber 806 through the gas holes 129 and flowing into the oil separation chamber 128a also flows into the upper shell 801a2, the wall surface of the frame 126, and the portion of the motor power supply connection terminal 88. After colliding and separating from the discharged refrigerant gas, and collected at the center of the frame 126, the spiral oil groove 741 provided on the drive shaft 704
During the passage through d, the lubricating portion returns to the motor chamber 806 while lubricating the sliding portion of the upper bearing 811.

A part of the lubricating oil in the refrigerant gas discharged from the motor chamber 806 adheres to the surface of the lower winding of the motor 703 and separates from the refrigerant gas to be collected in the discharge chamber oil reservoir 34. However, the lubricating oil in the discharged refrigerant gas passing through the outer periphery of the upper balance weight 775 and the lower balance weight 776 is centrifuged by the rotation of the upper balance weight 775 and the lower balance weight 776, and the motor 70
No. 3 is diffused to the inner surface of the winding, flows downward along the inner space of the winding bundle, and is collected in the discharge chamber oil reservoir 34.

As a result of the separation of the lubricating oil in the discharged refrigerant gas and the operation of collecting the lubricating oil into the motor chamber 806, the amount of the lubricating oil sent from the discharge pipe 831 to the external refrigeration cycle is extremely small, and most of the lubricating oil is Can be used for refueling the compression mechanism described in detail below.

Further, as in the initial stage of starting the compressor when the compressor is cold, the liquid refrigerant mixed into the discharge chamber oil reservoir 34 foams following the rise in the temperature in the motor chamber 806, and the lubricating oil in the discharge chamber oil reservoir 34 is discharged. Although it moves to the upper part in the motor chamber 806 together with the discharged refrigerant gas, it does not move much to the oil separation chamber 128a because it is blocked by the frame 126. Further, a gas hole 129 is provided at a position facing the motor coil end 130,
The lubricating oil that is going to flow into the oil separation chamber 128a is captured by the motor coil end 130 and can be collected in the discharge chamber oil reservoir 34.

The lubricating oil in the discharge chamber oil reservoir 34 is supplied to the oil chamber A 778a, the oil chamber B 778b, and the back pressure chamber 8 through a path described later.
39, and finally flows into the suction chamber 17, while gradually turning the orbiting scroll 81 by the lubricating oil pressure in the oil supply path.
8 increases the back pressure applying force.

Following the pressure increase in the motor chamber 806, the lap support disk 818c gradually comes into contact with the end plate sliding surface 815b2 of the fixed scroll 815 with an appropriate pressing force. Tip of fixed scroll wrap 815a and orbiting scroll 81
8, the gap between the lap support disk 818c is eliminated,
As a result, the compression chamber is sealed, the suction refrigerant gas is efficiently compressed, and stable operation is continued.

The axial gap between the end of the orbiting scroll wrap 818a and the end plate 815b of the fixed scroll 815 is formed when the refrigerant gas during compression leaks to the adjacent low-pressure side compression chamber 98 (see FIG. 3), and the gas back pressure causes the tip seal 98a to be pressed against the side surface of the low compression chamber of the tip seal groove 98a and the end plate 815b of the fixed scroll 815 to be sealed.

When the compressor is stopped, the orbiting scroll 818 instantaneously makes a reverse orbital motion due to the backflow based on the pressure difference of the refrigerant gas in the compression chamber. However, since the refrigerant gas flows back from the compression chamber to the suction chamber 17, As shown in FIG. 12, the orbiting scroll 818 has the first compression chambers 61a and 61b
Stop at the turning angle that leads to. As shown in FIG. 8, in this stopped state, the annular ring 94 closes the lubricating oil inlet to the back pressure chamber 839.

When the compressor is stopped, the refrigerant gas in the compression chamber flows back into the suction chamber 17 so that the refrigerant gas pressure in the discharge port 16 drops sharply, and the refrigerant gas pressure difference between the discharge port 16 and the discharge chamber 2 is reduced. As a result, the valve body 50b is
To prevent continuous backflow of the refrigerant gas discharged from the discharge chamber 2 to the compression chamber.

The reverse flow of the temporarily discharged refrigerant gas immediately after the compressor stops and the reverse rotation of the orbiting scroll 818 cause the valve element 5 to rotate.
0b is detached from the bottom surface of the check valve chamber 50a and the valve element 51 is generated by the pressure difference until the refrigeration cycle balances the pressure.
b keeps closing the discharge port 16. At the same time, the coil spring 50 having the shape memory characteristic decreases in temperature and expands, and the urging force of the coil spring 50 keeps the valve body 50b closing the discharge port 16.

When the compressor is stopped for a long time, the pressure in the compressor is balanced, and the liquid refrigerant flows into the compression chamber as well as the accumulator chamber 846, so that liquid compression is likely to occur in the initial stage of the cold start of the compressor. A thrust force in the direction opposite to the discharge port 16 acts on the orbiting scroll 818 by the pressure of the liquid compressed refrigerant in the compression chamber. As a result, the orbiting scroll 818
Are separated from the fixed scroll 815 in the axial direction, and the compression load is reduced.

On the other hand, the back pressure chamber 839 at the initial stage of the cold start of the compressor.
Is almost equivalent to the suction pressure because the rise in the lubricating oil pressure in the discharge chamber oil reservoir 34 is low. As a result, the lap support disk 818c of the orbiting scroll 818 is separated from the end plate sliding surface 815b2 in a state where the back pressure is applied only by the lubricating oil in the oil chamber A778a with a low pressure rise, and the thrust bearing 2
0, and is supported to the gap between the wrap support disk 818c and the tip of the fixed scroll wrap 815a (about 0. 0).
015 to 0.020 mm), the compression chamber pressure is reduced, and the compression load at the initial stage of startup is reduced.

If, for example, liquid compression occurs in the compression chamber during continuous operation and the pressure in the compression chamber rises abnormally instantaneously, the thrust force acting on the orbiting scroll 818 is applied to the back of the orbiting scroll 818. The orbiting scroll 818 moves in the axial direction,
It is supported by a thrust bearing 220. Then, the sealing of the compression chamber is released in the same manner as described above, the compression chamber pressure is reduced, and the compression load is reduced.

The back pressure chamber 839 is connected to the first compression chamber 61
Since a and 61b communicate with the outer peripheral space 37 via the oil groove 291 provided in the thrust bearing 220 within a turning angle range of about 180 degrees before the suction refrigerant gas is completely confined,
The lubricating oil in the back pressure chamber 839 does not continuously flow into the compression chamber via the oil groove 891 and the suction chamber 17, thereby suppressing the generation of oil compression in the compression chamber.

The lubricating oil in the discharge chamber oil reservoir 34 at the beginning of the cold start of the compressor is supplied to the spiral oil groove 741 provided on the drive shaft 704.
a, oil hole A838 by the screw pump action of 741b
The oil is sucked into the oil chamber A 778a via a.

Thereafter, a part of the lubricating oil is
b, the oil chamber B 778b, and the lubrication hole 112d sequentially lubricate the sliding surface of the turning bearing 818b on the way, and are supplied to the sliding surface of the main bearing 812 and sent out to the oil sump 772.

The main bearing 812 is formed by the spiral oil groove 741a.
The lubricating oil supplied to the lubricating oil joins with the lubricating oil that has passed through the oil chamber B778b in the oil sump 772, and then a part of the lubricating oil is depressurized in the throttle passage portion of the oil hole B738b (see FIG. 8), so that the back pressure is reduced. The chamber 839 is intermittently refueled. The remaining lubricating oil is returned to the discharge chamber oil reservoir 34 via an oil groove provided on the sliding surface of the thrust bearing 713 supporting the weight of the drive shaft 704 and the rotor 703a.

Note that the lubricating oil continuously supplied to the oil groove of the thrust bearing portion 713 flows into the motor chamber 806 between the oil sump 772 and the motor chamber 806, so that the refrigerant gas in the motor chamber 806 is summed up. While being prevented from flowing into the lubricating oil 772, part of the refrigerant gas contained in the lubricating oil in the oil sump 772 passes through the oil groove of the thrust bearing portion 713 which also functions as a bypass passage, and the upper motor chamber 8
06 to the back pressure chamber 83 from the oil sump 772.
Lubricating oil with little gas mixture is supplied to 9 and the compression chamber. Further, when the thrust bearing portion 713 is at a position higher than the oil level of the discharge chamber oil reservoir 34 and the compressor is not supplied with oil to the thrust bearing portion 713, the oil reservoir 772 and the discharge chamber oil reservoir 3
4 is short-circuited via the refrigerant gas in the motor chamber 806. In this state, the lubricating oil in the discharge chamber oil reservoir 34 is prevented from flowing into the compression chamber due to a differential pressure or a height difference, and shortage of lubricating oil in the discharge chamber oil reservoir 34 and overload due to oil compression when the compressor is restarted are avoided. Is done.

The vertical vibration of the drive shaft 704 caused by the high-speed sliding contact of the end face of the lower balance weight 776 with the thrust bearing portion 713 is caused by the end face of the upper balance weight 775 being the end of the upper bearing (hereinafter referred to as the auxiliary bearing) 711. It is regulated in contact with the department.

The oil supply to the auxiliary bearing 711 is performed by the cooling passage 35,
Oil separation space 128 through gas holes 129 of frame 126
The lubricating oil separated from the refrigerant gas flowing into a and collected at the center of the frame 126 is supplied by the screw pump action of the spiral oil groove 741d.

The pressure of the refrigerant gas discharged from the motor chamber 806 increases following the elapse of time after the start of the compressor in cold mode. Helical oil grooves 741a, 741
The oil is supplied to the back pressure chamber 839 together with the screw pumping action of b. The pressure in the back pressure chamber 839 gradually increases, and the oil chamber A77
8A acts on the wrap support disk 818c of the orbiting scroll 818. As a result, the thrust load acting to separate the orbiting scroll 818 from the fixed scroll 815 is canceled by the refrigerant gas pressure in the compression chamber, and the thrust force acting on the orbiting scroll 818 is reduced.

Therefore, while the pressure rise in the motor chamber 806 after the cold start of the compressor is low, the force exerted on the orbiting scroll 818 by the lubricating oil pressure in the oil chamber A 778a and the back pressure chamber 839 increases the refrigerant gas pressure in the compression chamber. Orbiting scroll 81
8 less than the thrust load. As a result, the orbiting scroll 818 is separated from the fixed scroll 815 and supported by the thrust bearing 220 which receives the elastic force of the coil spring 131 and the seal ring 70 and the back pressure due to the lubricating oil introduced from the discharge chamber oil reservoir 34.

When the pressure difference between the discharge pressure and the suction pressure exceeds the required pressure, the force exerted on the orbiting scroll 818 by the lubricating oil pressure in the oil chamber A 778a and the back pressure chamber 839 causes the orbiting by the refrigerant gas pressure in the compression chamber. It becomes larger than the thrust load on the scroll 818. And the orbiting scroll 818
Are supported by the fixed scroll 815.

The center of the compression chamber, the center of the slewing bearing 818e,
In the arrangement in which the centers of the annular rings 94 are substantially coincident with each other, since the annular ring 94 orbits together with the orbiting scroll 818, the annular ring 94 tends to jump out of the annular seal groove 95 provided in the orbiting boss 818e by the inertia force at that time. . The annular ring 94 expands its inner diameter by the pressure difference between the oil chamber A 778a and the back pressure chamber 839, and closes the cutout 94b together with the thermal expansion. By these actions, the annular ring 94 is pressed against the outer surfaces of the main body frame 805 and the annular seal groove 95, and the annular seal groove 95 and the annular ring 94 are scraped by the oil scraping action of the annular ring 94.
Between the oil chamber A 778a and the back pressure chamber 839 to prevent excessive leakage of the lubricating oil.

Further, the resin-made annular ring 94 having excellent flexibility expands its inner diameter along the outer surface of the annular seal groove 95 due to a pressure difference between the back pressure chamber 839 and the oil chamber A778a, thereby reducing heat. The cutout 94b is closed together with the expansion, and at the same time, the cutout 94b is pressed against the outer surface of the annular seal groove 95, so that leakage between the two spaces is further reduced.

The annular ring 94 is formed by an oil film of lubricating oil accumulated in an oil groove 94a provided on the surface of the annular groove 94.
By lubricating the sliding surface between the sliding surface and the body frame 805, wear and sliding resistance of the sliding surface are reduced.

During the normal operation of the compressor, the high pressure oil chamber A778
The orbiting scroll 818 is given a back pressure to the fixed scroll 815 side by the lubricating oil pressure of a and the lubricating oil pressure of the back pressure chamber 839, and the lap support disk 818 c and the end plate sliding surface 815
B2 slides smoothly while maintaining an appropriate contact force, thereby minimizing the axial gap of the compression chamber.

The lubricating oil flowing into the back pressure chamber 839 intermittently flows into the outer peripheral space 37 through an oil groove 291 provided in the thrust bearing 220, and further flows through an oil groove 891 provided in the end plate 815b. And flows into the suction chamber 17. Lubricating oil is
The sliding surfaces are lubricated in the course of the passage to seal the sliding gap.

The lubricating oil that has flowed into the compression chamber (compression space) together with the suctioned refrigerant gas seals a minute gap between adjacent compression chambers with an oil film to prevent leakage of the compressed refrigerant gas and lubricate the sliding surfaces between the compression chambers. The compressed refrigerant gas is discharged again to the motor chamber 806 via the discharge port 16 together with the compressed refrigerant gas.

In the oil supply path from the discharge chamber oil reservoir 34 through the back pressure chamber 839 to the suction chamber 17, the back pressure chamber 839 maintains an appropriate intermediate pressure between the discharge pressure and the suction pressure.

Further, since the compression ratio of the scroll refrigerant compressor is constant, when the differential pressure between the suction chamber 17 and the discharge chamber 2 is small, such as immediately after the start in cold operation, or abnormal liquid compression occurs. In such a case, as described above, the orbiting scroll 8
18 moves away from the fixed scroll 815 and is supported by the thrust bearing 220.

However, the thrust bearing 220 urged by the back pressure cannot support the abnormally increased compression chamber pressure load, and retreats in a direction to reduce the release gap 27, and is fixed to the lap support disk 818c of the orbiting scroll 818. The axial gap between the scroll 815 and the tip of the fixed scroll wrap 815a increases. As a result, a large amount of leakage occurs between the compression chambers, and the pressure in the compression chamber suddenly drops during the compression as shown by the one-dot chain line 63a in FIG.

The orbiting scroll 818 is the fixed scroll 8
Since the maximum distance apart from 15 in the axial direction is regulated to about 70 microns, an oil film remains in each gap between the sliding surfaces on both sides of the lap support disk 818c, and the lubricating oil flows from the outer peripheral space 37 to the suction chamber 17. After the pressure change in the back pressure chamber 839 due to the excessive inflow is suppressed and the compression load is instantaneously reduced, the thrust bearing 220 can instantly return to the original position, and the stable operation is continued again.

When the orbiting scroll 818 retreats toward the thrust bearing 220, the orbiting scroll wrap 81
Although the axial dimension between the tip of the fixed scroll 815 and the tip of the fixed scroll 815 also increases, since the tip seal 98a is pressed against the fixed scroll 815 by the gas pressure on the back surface, compressed refrigerant gas leakage from this portion will not occur. Rarely occurs.

On the other hand, the gap between the wrap support disk 818c of the orbiting scroll 818 and the tip of the fixed scroll wrap 815b of the fixed scroll 815 is enlarged, and compressed refrigerant gas leaks in the compression chamber, causing a sudden increase in the pressure in the compression chamber. descend.

Also, when foreign matter is caught in the axial gap between the orbiting scroll 818 and the fixed scroll 815, the thrust bearing 220 retreats and removes the foreign matter as described above.

In the initial stage of cold start or during steady-state operation, when the instantaneous liquid compression occurs, the compression chamber pressure is abnormally over-compressed as shown by a dotted line 63 in FIG.
The high pressure space volume communicating with the
0a, the discharge chamber 2, and the discharge chamber 2c, the expansion is repeated while passing sequentially, and the pressure in the motor chamber 806 hardly changes.

In the above embodiment, the oil hole B 738b of the main frame 805, the oil groove 291 of the thrust bearing 220, and the oil groove 891 of the end plate 815b are set so that the back pressure chamber 839 has an intermediate pressure between the discharge pressure and the suction pressure. However, the back pressure chamber 839 may be set to be equivalent to the suction pressure according to the load condition of the compressor.
8 depends only on the lubricating oil pressure of the oil chamber A778a.

Further, in the above embodiment, the outer peripheral space 37 is communicated with the suction chamber 17, but the outer peripheral space 37 is provided with an oil hole 838 provided in the lap support disk 818c of the orbiting scroll 818.
The first compression chambers 61a and 61b may be connected to the first compression chambers 61a and 61b (see FIG. 10).

(Embodiment 2) In the above embodiment, spiral oil grooves 741a and 741b are provided in the bearing sliding portion of the drive shaft 704 on the compression mechanism side, and the screw pump is formed by the spiral oil grooves 741a and 741b. Although the lubricating oil is supplied by the action, as described below, the lubricating oil may be supplied to the bearing sliding portion by the positive displacement pump device disposed at the end of the drive shaft.

That is, FIG. 14 shows the second state of the bearing sliding portion.
FIG. 3 is a partial cross-sectional view of a portion around a refueling means of the main frame 305.
The partition cap 101 made of a steel plate is press-fitted into the stepped inner wall of the high-pressure oil chamber A 378 a which communicates with the discharge chamber oil reservoir 34 via the oil hole A 338 a provided in the drive shaft 30.
The oil chamber A 378 is disposed so as to cover the brim portion 102 of the fourth oil chamber.
a is divided into a main bearing 312 side and a swing bearing 318b side.

The orbiting boss 318 of the orbiting scroll 318
A swing bearing 318bb is press-fitted in e, and a trochoid pump device 106 including an outer rotor 106a and an inner rotor 106b is mounted on the bottom thereof.

The trochoid pump device 106 is
4 is connected to and driven by a drive end shaft 107 provided at the end of the crankshaft 314 at the end of the fourth end. The crankshaft 314 and the drive end shaft 107 are concentric.

As shown in FIG. 15, a suction hole 108 is provided between the slewing bearing 318b and the trochoid pump device 106.
And a partition plate 110 having a central hole 109 is fixedly mounted.

Wrap support disk 3 of orbiting scroll 318
The oil groove 111 provided at the central portion of 18c serves as a discharge port of the trochoid pump device 106.
The sliding surface of the main bearing 312 is in communication with an axial oil hole 112 and a radial oil hole 113 provided in the drive shaft 304.

The discharge chamber oil reservoir 34 and the back pressure chamber 339 of the orbiting scroll 318 are connected to an oil hole A338a, an oil chamber A378a,
An oil supply passage A communicating with the oil sump 72 via the spiral oil groove 341b, the suction hole 108, the trochoid pump device 106, the oil groove 111, the axial oil hole 112, the radial oil hole 113, and the bearing gap of the main bearing 312. And an oil supply passage C composed of an oil supply passage B which communicates with the oil sump 72 from the oil chamber A 378a via the spiral oil groove 341a, and an oil hole B38b.

Next, the operation of the above embodiment will be described.

Simultaneously with the start of the compressor, the lubricating oil in the discharge chamber oil reservoir 34 at the bottom of the motor chamber 6 is supplied to the screw pump of the spiral oil grooves 341 a and 341 b provided on the drive shaft 304 and to the lower end of the drive shaft 304. The trochoid pump device 106 is sucked into an oil chamber A378a through an oil hole A338a provided in the main body frame 305. At this time, the lubricating oil is
Oil chamber A378a and the spiral oil groove 34
1b, and when the lubricating oil flows into the oil chamber A378a from the oil hole A338a, the helical oil is not affected by the centrifugal diffusion caused by the high speed rotation of the drive shaft 304 (for example, 6000 rpm or more). The oil is sucked into the groove 341a, and excellent screw pump lubrication is performed.

While lubricating the sliding surface of the slewing bearing 318b, the trochoid pump device 1 passes through the spiral oil groove 341b.
The lubricating oil flowing into the suction hole 06 is discharged to the oil groove 111, then supplied to the main bearing 312 through the oil hole 112 and the radial oil hole 113, and discharged to the oil sump 72.

The main bearing 31 passes through the spiral oil groove 341a.
The lubricating oil discharged to the oil sump 72 while lubricating the lubricating oil 2 merges with the lubricating oil discharged from the trochoid pump device 106, and a part of the lubricating oil is intermittently reduced while being reduced in pressure through the oil hole B38b. 339 is refueled.

The remaining lubricating oil discharged into the oil sump 72 is
After the upper bearing 311 and the thrust bearing 313 are lubricated, they are collected in the discharge chamber oil reservoir 34.

As the time elapses after the compressor is started, the pressure in the motor chamber 6 filled with the discharged refrigerant gas gradually increases, and the lubricating oil in the discharge chamber oil reservoir 34 is discharged from the discharge chamber oil reservoir 34 and the back pressure chamber of the orbiting scroll 318. 339 and the back pressure chamber 3
Refuel up to 39.

The refueling from the back pressure chamber 339 to the compression chamber and other operations are the same as those in FIG. 1 and will not be described.

In the above embodiment, the scroll refrigerant compressor has been described.
Similar effects can be expected in the case of a gas compressor that compresses a gas such as helium by another type such as a rotary type or a reciprocating type compressor.

In the above embodiment, the structure of the vertical compressor is shown and its effect is explained.
8a, the same effect can be expected for the configuration of the horizontal compressor in which the upstream end of the oil hole 338a in FIG.

[0120]

As is clear from the above embodiment, the present invention
Is a spiral oil groove provided in a bearing sliding portion of a drive shaft in a configuration in which a differential pressure oil supply passage communicating from a discharge chamber oil reservoir provided at a bottom portion of a motor chamber to a suction / compression space of a scroll compression mechanism is provided. The lubricating oil in the discharge chamber oil sump is supplied to the sliding surfaces of the main bearing and the swivel bearing portion by using the screw pump function of the above and one of the pump means of the positive displacement pump device driven by the drive shaft. After that, a circulation pump path for the bearing oil supply passage is provided for returning the oil to the discharge chamber oil reservoir via the motor chamber, while a part of the bearing oil supply passage receives lubricating oil from the discharge chamber oil reservoir in the differential pressure oil supply passage. .Gas from the motor chamber to the middle of the differential pressure oil supply passage only when the compressor is stopped, while the remaining passage is also provided while branching from the middle of the differential pressure oil supply passage while serving also as a passage to the branch point toward the compression space. Bypass of differential pressure oil supply passage that allows inflow According to this configuration, sufficient lubrication can be applied to the sliding surfaces of the main bearing and the slewing bearing regardless of the amount of lubricating oil supplied to the compression chamber. Can be reduced. Further, since the gas in the lubricating oil supplied to the compression chamber can be degassed, it is possible to reduce the discharge gas inflow amount when supplying the lubricating oil to the compression chamber, thereby preventing a reduction in compression efficiency. Also, immediately after the compressor stops, even if there is a residual pressure difference between the discharge chamber oil sump and the suction / compression space, the gas from the motor chamber flows in the middle of the differential pressure oil supply passage. The effect of preventing oil from flowing into the compression chamber, preventing shortage of lubricating oil and occurrence of oil compression at the time of restarting the compressor, and preventing poor startup and reduced durability can be achieved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a scroll refrigerant compressor showing one embodiment of the present invention.

FIG. 2 is an exploded view of main parts of the compressor.

FIG. 3 is a partial sectional view of a check valve device arranged at a discharge port of the compressor.

FIG. 4 is a perspective view of components of the check valve device in FIG. 3;

FIG. 5 is a perspective view of components of the check valve device.

FIG. 6 is a perspective view of components of the check valve device.

FIG. 7 is an exploded perspective view of small parts in the compressor.

FIG. 8 is a partial cross-sectional view of a main bearing in the compressor.

FIG. 9 is a perspective view of a seal component in the compressor.

FIG. 10 is a partial cross-sectional view of a thrust bearing portion of the compressor.

11 is a perspective view of the thrust bearing in FIG.

FIG. 12 is a transverse sectional view taken along line AA in FIG. 1;

FIG. 13 is a characteristic diagram showing a change in pressure of the refrigerant gas from a suction stroke to a discharge stroke of the compressor.

FIG. 14 is a partial sectional view showing an oil supply passage by the positive displacement pump device according to one embodiment of the present invention;

FIG. 15 is an external view of a partition plate used in the same displacement type pump device.

FIG. 16 is a longitudinal sectional view of a conventional scroll compressor.

[Explanation of symbols]

 34 Discharge chamber oil reservoir 88 Motor power connection terminal 126 Frame 128a Oil separation chamber 129 Gas hole 130 Coil end 703 Motor 704 Drive shaft 741d Spiral oil groove 801 Closed case 806 Motor chamber 811 Secondary bearing 831 Discharge pipe

Continuation of front page (56) References JP-A-1-177482 (JP, A) JP-A-59-183095 (JP, A) JP-A-58-91392 (JP, A) JP-A-1-142282 (JP, A) , A) JP-A-62-37318 (JP, A) JP-A-62-165591 (JP, A) JP-A-59-2995 (JP, U) JP-A-51-23924 (JP, Y2) (58) Field surveyed (Int. Cl. ⁷ , DB name) F04C 23/00-29/10 331 F04C 18/02 311

Claims (1)

(57) [Claims] 1. A swirling orbiting scroll wrap on a wrap support disk which forms a part of an orbiting scroll with respect to a spiral fixed scroll wrap formed on one surface of a head plate forming a part of a fixed scroll. Mesh freely,
A suction / compression space is formed between the two scrolls, a discharge port is provided at the center of the fixed scroll wrap or the orbiting scroll wrap, a suction chamber is provided outside the fixed scroll wrap, and the wrap support disk is driven. A orbiting bearing portion that supports a shaft and is disposed between the body frame having a main bearing near the orbiting scroll and the head plate, and the orbiting scroll engages with the drive shaft to slide. A scroll-type compression mechanism portion rotatably supported by the drive shaft via a rotation-preventing mechanism of the lap support disk to compress a fluid by utilizing a change in volume of the suction / compression space; and the drive shaft. Is housed in a closed case, and the discharge gas discharged from the scroll-type compression mechanism section passes through the motor chamber that houses the motor. A discharge gas passage for discharging to the outside of the motor chamber, and a differential pressure oil supply passage communicating from the discharge chamber oil reservoir provided at the bottom of the motor chamber to the suction / compression space of the compression mechanism. The screw chamber of the helical oil groove provided in the bearing sliding portion of the shaft and the pumping means of one of the positive displacement pump devices driven by the drive shaft are used to store the oil in the discharge chamber oil reservoir. After supplying a lubricating oil to at least the sliding surfaces of the main bearing and the slewing bearing, a circulating pump path of a bearing oil supply passage for returning the oil to the discharge chamber oil reservoir via the motor chamber is provided. A part of the passage also serves as a passage to the branch point where the lubricating oil from the discharge chamber oil reservoir in the differential pressure oil supply passage goes to the suction / compression space, and the remaining passage is in the middle of the differential pressure oil supply passage. Branching off from Compressor scroll gas compressor which also serves as a bypass passage of the differential pressure feed oil passage for permitting gas flowing into the middle of the difference pressure feed oil passage only from the motor chamber is stopped.