JP2870488B2 - Scroll 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 oil supply to a bearing portion of a scroll gas compressor and an oil supply passage accompanying the oil supply to the back of the orbiting scroll.

[0002]

2. Description of the Related Art In a scroll compressor having low vibration and low noise characteristics, a suction chamber is provided at an outer peripheral portion, a discharge port is provided at a central portion of a spiral, and a flow of compressed gas is reciprocated in one direction. If there is no need for a discharge valve for compressing fluid such as a compressor or rotary compressor, and there is no large variation in the operating compression ratio determined by the suction pressure and the discharge pressure, the suction volume of the compression chamber and the final compression Since the discharge pulsation is small and a large discharge space is not required by setting the volume ratio determined by the chamber volume to an appropriate value, research on practical use of 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,
The dimensional accuracy of the spiral part must be extremely high in order to reduce the leakage gap in the compression part, but the cost of the scroll gas compressor is high due to variations in the dimensional accuracy of the spiral part due to the complexity of the part shape. In addition, there is a large variation in performance, especially in the low-speed operation state of the compressor, the gas leakage rate during compression is large, and the compression efficiency is lower than that of a reciprocating compressor or a rotary compressor.

Therefore, as measures for solving this kind of problem, it is expected to optimize the dimensional accuracy of the spiral part in order to prevent gas leakage during compression and to improve the compression efficiency by an oil film sealing effect using lubricating oil. And JP-A-57-83
As described in Japanese Patent Publication No. 86, a proposal has been made to improve the above-mentioned disadvantages by injecting a proper amount of lubricating oil into a compression chamber in the middle of compression, sealing a gap in the compression chamber with an oil film of lubricating oil.

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-sized compressors having a relatively large refrigerant volume per suction stroke, such as package air conditioners and chiller units, have been developed. Improvements have been made and mass production has already been achieved.

FIG. 18 shows a general structure example 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, and the intermediate pressure lubricating oil and the high pressure lubricating oil on the upper part of the crankshaft cause the rear surface of the orbiting scroll 1006 to move. 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.
, Flows into the compression chamber 1015 during compression, is compressed / discharged together with the suction refrigerant gas while sealing the gap of the compression chamber 1015, and is discharged to the discharge chamber 1031.
(JP-A-56-165788).

[0008]

However, the configuration shown in FIG. 18 has the following two problems.

The gist of the first problem is that the oil supply to the compression chambers is inevitably increased due to the necessity of sufficient lubrication to the two bearing portions, and the incompressible lubricating oil is compressed. The compression input becomes large, and the compression efficiency is reduced.

That is, the drive shaft (crankshaft) 1
008, two bearing sliding portions [an upper bearing sliding portion provided on a main body frame (frame) 1009 supporting a drive shaft (crankshaft) 1008 and a bearing sliding of a crank portion for rotating the orbiting scroll 1006] Part] and motor (motor) and drive shaft (crankshaft) 100
In the configuration in which lubricating oil is supplied to the thrust bearing portion supporting its own weight with the compressor 8 and then flows into the compressor 1015, the amount of oil flowing into the compression chamber 1015 increases due to the necessity of sufficient oil supply to the bearing sliding portion. However, the lubricating oil heated at a high pressure and the refrigerant gas mixed in the lubricating oil flow into the compression chamber 1015 in the middle of compression, so that the compression efficiency is reduced.

The second problem is that a large amount of lubricating oil flows into the compression chamber, resulting in an increase in the size of the compressor.

That is, the discharge chamber 1031 having a volume necessary for separating the lubricating oil in the refrigerant gas is provided in the compression chamber 101.
5, the motor (rotor 1011 and stator 1012) and the oil sump are arranged in the lower part, and the space for separating the lubricating oil from the refrigerant gas and the motor (rotor 1
011 and the stator 1012), and the space for cooling the motor is different, so that there is a problem that the outer dimensions of the compressor are increased.

On the other hand, as a measure for solving the above-mentioned problem (enlargement), as shown in FIG.
The lower part of 201 has a compression part, and the upper part has a motor (motor) 12.
03, a discharge chamber oil sump (oil sump) 1215 at the bottom, and a discharge gas discharge pipe (delivery pipe) 1217 on the top wall, and a compressed refrigerant gas discharged through a discharge pipe 1214 to a motor (electric motor) 1.
After being guided to a space for accommodating 203 (not shown), cooling the motor (motor) 1203 and separating the lubricating oil in the refrigerant gas, the oil is discharged from the discharge pipe (delivery pipe) 1217 to the outside of the apparatus, while the drive shaft ( A bearing part supporting the crankshaft 1204 and the compression chamber are immersed in a discharge chamber oil sump (oil sump) 1215 and provided on a boss 1205 a of a main body frame (frame) 1205 supporting the drive shaft (crankshaft) 1204. Bearing hole of the main bearing (bearing portion) supporting the drive shaft (crankshaft) 1204, a back pressure chamber (intermediate chamber) 1208 provided between the main frame (frame) 1205 and the orbiting scroll 1206. , Orbiting scroll 12
The lubricating oil in the discharge chamber oil sump (oil sump) 1215 is supplied to the compression chamber 1216 at a differential pressure through a communication hole 1211 provided in the compressor 06. (Oil pool) Even when the pressure increase of the pressure 1215 is small, the sliding portion of the bearing can be lubricated (Japanese Patent Laid-Open No. 57-35184).

However, as in the case of FIG. 18 described above, the total amount of the lubricating oil that has lubricated the main bearing (bearing portion) supporting the drive shaft (crankshaft) 1204 is stored in the compression chamber 1216.
On the other hand, in addition to the weight of at least the drive shaft (crankshaft) 1204 and the motor (electric motor) 1203 in the middle of the path, the discharge chamber oil sump (oil sump) 1215 and the back pressure chamber (intermediate chamber) 1208 Since the downward thrust force acting on the drive shaft (crankshaft) 1204 due to the differential pressure also needs to be supported by the orbiting scroll 1206, the compression chamber 1216
There is a problem that the amount of lubricating oil flowing into the cylinder further increases, causing a significant decrease in compression efficiency.

As described above, it is difficult to simultaneously reduce the compressor input, the compression efficiency, and the size of the compressor by simply combining the conventional techniques.

An object of the present invention is to solve such a conventional problem, and an object of the present invention is to provide a small scroll gas compressor having low input and high compression efficiency.

[0017]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a differential pressure oil supply passage for finally supplying lubricating oil in a discharge chamber oil reservoir to a compression chamber via a sliding portion of a slewing bearing. On the other hand, the lubricating oil of the discharge chamber oil reservoir arranged at a considerable height from the main bearing is sucked and discharged by the screw pump action of the oil groove provided on the sliding surface of the main bearing, and then returned to the discharge chamber oil reservoir again. A bearing oil supply passage is provided.

With the structure of the bearing oil supply passage and the differential pressure oil supply passage, sufficient oil supply to the main bearing can be realized by a simple and low-input oil supply means, while oil film sealing of the compression chamber gap by appropriate amount of oil supply to the compression chamber is achieved. it can.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, a scroll compression mechanism is housed in a lower part of a closed case, and is provided on a drive shaft.
Store the motor to be connected in the upper part of the sealed case, and
After the gas exhausted from the heat sink cools the motor,
A discharge gas passage that is discharged outside the
The oil level of the working chamber oil sump is located below the motor and the main bearing
At the same height as the upper end of the slewing bearing
The compression disk and the suction chamber
Differential pressure lubrication to supply lubricating oil in the discharge chamber oil sump to either one
In the configuration with a passage, it is located inside the thrust bearing
And adjacent to the main bearing, the slewing bearing and the lap support disk
The oil chamber in which the discharge pressure works
In the middle of the road, and over the entire axial direction of the sliding surface of the main bearing.
The screw pump action of the spiral oil groove provided by
Lubricating oil is introduced into the oil chamber from the discharge chamber oil sump,
Branch to the differential pressure lubrication passage while lubricating most of the rest
A bearing oil supply passage for returning oil to the discharge chamber oil sump was formed.
It is. According to this configuration, when the lubricating oil in the discharge chamber oil reservoir is introduced into the oil chamber by the screw pump action of the spiral oil groove, the suction action is assisted by the differential pressure with the compression chamber (or the suction chamber). This facilitates the introduction of lubricating oil into the oil chamber, facilitates securing the required amount of pump lubrication during low-speed to high-speed operation, and shortens the pump lubrication passage. Extremely low. Further, the lubricating oil in the oil chamber urges the anti-compression side of the orbiting scroll to reduce the thrust force acting on the orbiting scroll, thereby reducing the frictional resistance of the axial sliding contact surface of the orbiting scroll.

According to a second aspect of the present invention, the sliding surface of the main bearing is provided.
In the bearing oil supply passage downstream of the spiral oil groove provided in
And another spiral oil groove provided on the sliding surface of the drive shaft.
Dipump means, and at least the weight of the drive shaft and motor
A thrust bearing that supports
Is placed. According to this configuration, the damage caused by the lubricating oil whose temperature has increased in the thrust bearing portion flowing into the compression chamber is reduced.

According to a third aspect of the present invention, the thrust bearing is disposed at the end of the bearing oil supply passage. According to this configuration, while avoiding the adverse effects caused by the lubricating oil whose temperature has increased in the thrust bearing portion flowing into the compression chamber,
The adverse effect on the lubrication performance of the main bearing can also be avoided.

[0022]

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 FIGS. 1 to 15, reference numeral 1 denotes an iron sealed case, the contents of which are orbiting scrolls 218.
Body frame 2 that bolts fixed scroll 15 that forms a compression chamber by meshing with
05, the upper motor chamber 6 and the lower accumulator chamber 46 are partitioned.

The motor chamber 6 has a high-pressure atmosphere. The motor frame 3 is disposed at the upper part and the compression part is disposed at the lower part.
Is made of eutectic graphite cast iron having excellent sliding characteristics and weldability, and a projection 79a provided on the outer peripheral surface thereof is in contact with the inner wall surface and the end surface of the upper sealed case 1a and the lower sealed case 1b. The projection 79a, the upper sealing case 1a, and the lower sealing case 1b are hermetically welded by a single welding beat 79b.

The drive shaft 204 includes an upper bearing 211 provided at the upper end of the main body frame 205, a main bearing 212 provided at the center, and a plurality of radial shallow grooves 7 provided at the upper end surface of the main body frame 205. Thrust bearing portion 21 having
The crankshaft 214 at the lower end eccentric from the main shaft of the drive shaft 204 is engaged with the orbiting bearing 218 b of the orbiting boss 218 e provided on the orbiting scroll 218.

The fixed scroll 15 is made of a high silicon aluminum alloy having a coefficient of thermal expansion corresponding to an intermediate value between pure aluminum and eutectic graphite cast iron, and has a spiral fixed scroll wrap 15a and a head plate as shown in FIG. 15b, and a fixed scroll wrap 1 is provided at the center of the end plate 15b.
The discharge port 16 opening at the winding start portion of the motor chamber
A suction chamber 17 is provided on the outer periphery of the fixed scroll wrap 15a.

On the end plate 15b on the anti-orbiting scroll side,
A check valve device 50 is attached so as to cover the discharge port 16, and the check valve device 50 is formed of a thin steel plate having a shape in which the outer peripheral portion is cut out at several places as described in detail in FIGS. 3 to 6. A valve case 99 having a valve body 50b (or a valve body 50e having a discontinuous annular hole 50ea), a check valve hole 50a, a central hole 50g, and a plurality of small discharge holes 50h around the valve hole 99a.
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.
It has a shape memory characteristic that expands below. During operation of the compressor, it receives the refrigerant gas pressure and shrinks to the bottom of the check valve hole 50a, and stops the compressor when its own temperature is 50 ° C or less. The inside is set so as to press the valve body 50 against the end plate 15b so as to close the discharge port 16.

As shown in FIGS. 1 and 14, a spiral orbiting scroll wrap 218a meshing with the fixed scroll wrap 15a to form a compression chamber side wall, and a drive shaft 20 are provided.
The orbiting scroll 218 made of an aluminum alloy, comprising a lap support disk 218c in which the orbiting boss 218e engaged with the crankshaft 214 of the No. 4 is upright, is disposed so as to be surrounded by the fixed scroll 15 and the main body frame 205, The surfaces of the lap support disk 218c and the orbiting scroll wrap 218a are subjected to hardening treatment such as porous nickel plating.

As shown in FIG. 3, a spiral tip seal groove 98 is provided at the tip of the orbiting scroll wrap 218a, and a resin tip seal 98a has a minute gap in the tip seal groove 98. It is installed. When the orbiting scroll 218 is pressed in the axial direction of the fixed scroll 15, the flat portion of the wrap supporting disk 218 c contacts the tip of the fixed scroll wrap 15 a, but the tip of the orbiting scroll wrap 218 a does not A minute distance of about a micron is maintained.

The discharge passage 80 (see FIG. 1) is provided in the discharge chamber 2 and the fixed scroll 15 formed by the discharge cover 2a mounted on the end plate 15b so as to cover the check valve device 50 and the end plate 15b. Gas passage B80b, gas A80a provided in main body frame 205, main bearing 21
The gas passage A 80a and the gas passage B 80b are provided at target positions, respectively, including a discharge guide 81 attached to the main body frame 205 so as to surround the main body 2 and a discharge chamber 2b formed by the main body frame 205 (see FIG. 14). ).

On the upper surface of the discharge guide 81, as shown in FIG.
Many small holes 81a are provided.

The accumulator chamber 46 communicating with the evaporator side of the refrigerating cycle is formed by the lower sealed case 1b, the fixed scroll 15, and the main body frame 205, and a suction pipe 47 communicating therewith is provided on a side surface of the lower sealed case 1b. Approximately 90 from each position facing the suction pipe 47
The suction hole 43 is fixed at two places separated by a distance
5 (see FIG. 14).

The low-pressure oil reservoir 46a at the bottom of the accumulator chamber 46 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 15. The oil suction holes (9a, 9b) are set so that the refrigerant liquid and the lubricating oil retained in the low-pressure oil reservoir 46a are sucked up by the generation of negative pressure when the refrigerant gas passes through the suction holes 43. I have.

A flat 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 205 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. 13) disposed between the lap support disk 218c and the main body frame 205 and interposed between the thrust bearing 220 and the main body frame 205. End plate mounting surface 15b between main body frame 5 and fixed scroll 15
It is in contact with 1.

Wrap support disk 2 of orbiting scroll 218
The height from the end plate sliding surface 15b2 slidingly in contact with the end plate 18c to the end plate mounting surface 15b1 is set to be equal to the height of the lap support disk 218c.
The thickness is set to be approximately 0.015 to 0.020 mm larger than the thickness of 18c.

As shown in FIGS. 1 and 8, an end face of the orbiting boss 218e of the orbiting scroll 218 on the main frame 205 side is provided with an annular seal groove 9 concentric with the center of the orbiting bearing 218b.
The annular seal groove 95 is provided with a flexible resin annular ring 94 having a cutout 94b by partially cutting the annular seal groove 95 as shown in FIG.
The outer peripheral surface of the annular ring 94 is in close contact with the side surface of the 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 the outer peripheral surface of the annular ring 94 Cut 94 with inclined angle
b are arranged to be in close contact with each other. Annular ring 94
Is the orbiting scroll 21 formed by the orbiting scroll 218, the body frame 205, and the thrust bearing 220.
Main bearing 212 supporting the back pressure chamber 39 and the drive shaft 204 of FIG.
Is sealed with the oil chamber A 278a on the side of
a to prevent excessive leakage from the back pressure chamber 239 to the back pressure chamber 239.

The annular thrust bearing 220 is made of a sintered alloy whose hole can be easily formed. As shown in FIGS. 12 and 13, 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 mounted in the thrust ring groove 90 of the main body frame 205.

Body frame 205 and thrust bearing 220
And a release gap 27 of about 0.05 mm is provided between them, and an annular groove 28 for mounting a seal ring 70 is provided inside and outside the release gap 27. The seal ring 70 seals between the release gap 27 and the back pressure chamber 239.

The release gap 27 is connected to the main body frame 205.
And a third compression chamber 60b (see FIG. 14) in the final compression stroke by means of a thrust back pressure introduction hole A89a provided in the first scroll and a thrust back pressure introduction hole B89b provided in the fixed scroll 15.

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 218 disposed inside 20 is made of a light alloy or a reinforcing 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 205, and the key portion on the lower surface is provided in a lap support disk 218c. It engages with the groove 71 and slides.

When the Oldham ring 24 reciprocates, the thickness of the main body frame 20 increases.
5 and the lap support disk 218c are set so as to slide smoothly and no jumping phenomenon occurs.

The discharge pipe 31 is attached to the outer peripheral portion of the upper end wall of the upper sealed case 1a, and the glass terminal 88 for connecting the motor power supply is attached to the central portion.

An oil separator 87 attached to the upper sealed case 1a separates the side of the discharge pipe 31 and the glass terminal 88 from the side of the motor 3. The rotor 3a of the motor 3 positioned in the axial direction by the stepped portion of the drive shaft 204
4, the upper balance weight 75 has a disk shape, and its outer diameter is set to be larger than the outer diameter of the rotor 3a.

Between the lower balance weight 76 attached to the lower end of the rotor 3a and the discharge guide 81, a shielding plate 86 attached to the main frame 205 is arranged close to the lower balance weight.

The discharge chamber oil reservoir 34 provided at the lower part of the motor chamber 6 is communicated with the upper part of the motor chamber 6 by a cooling passage 35 formed by cutting out a part of the outer periphery of the stator 3b of the motor 3. .

Further, the discharge chamber oil reservoir 34 is
05 through the oil hole A 238a provided in the main bearing 212
The oil chamber A 278a is located at an intermediate position between the oil chamber A 278b and the rotary bearing 218b.

As shown in FIGS. 1 and 8, the sliding shaft 204a of the drive shaft 204 and the surface of the crankshaft 214
When the drive shaft 204 rotates forward, the helical oil grooves 241a and 241b are formed in the direction in which the lubricating oil in the oil chamber A 278a is supplied to the motor 3 by a screw pump to the oil chamber B 278b formed by the swivel bearing 218b and the crankshaft 214. Provided,
The upper end reaches the thrust bearing 213.

Oil hole A2 provided in main body frame 205
High-pressure oil chamber A2 communicated with the discharge chamber oil reservoir 34
A partition cap 101 made of a steel plate having an external shape as shown in FIG. 9 is press-fitted into the stepped inner wall 78a, and is arranged so as to cover the brim portion 102 of the drive shaft 204 as shown in FIG. . The cap 101 has a cut 1
01a, which is mounted on the stepped inner wall of the oil chamber A278a, closes the cutout 101a, and partitions the oil chamber A278a into the main bearing 212 side and the swivel bearing 218b side.

The orbiting boss 218 of the orbiting scroll 218
FIG. 10E shows a slewing bearing 2 whose appearance is shown in FIG.
18b is press-fitted. Slewing bearing 21 having a cylindrical shape
A part of the outer peripheral portion of 8b is flattened, and the step C is set to about 100 microns. As shown in FIG. 8, the step C forms the throttle passage 103 in a state where it is press-fitted into the turning boss 218e.

The turning boss 218e is provided with an annular groove 104 and a small diameter oil hole 105. The discharge chamber oil reservoir 34 and the back pressure chamber 239 communicate with each other through an oil hole A238a, an oil chamber A278a, a spiral oil groove 241b, an oil chamber B278b, a throttle passage 103, an annular groove 104, and an oil hole 105.

As shown in FIG. 1, FIG. 13 and FIG. 14, the back pressure chamber 239 has a first compression chamber 61a, 61b intermittently communicating with the suction chamber 17 having a pressure of about 18 before the suction refrigerant gas is completely confined.
Within the turning angle range of 0 degrees, the oil groove 291 provided in the thrust bearing 220, the outer peripheral space 37 outside the lap support disk 218c, the oil hole C38c provided in the lap support disk 218c, and the symmetrical position. The first compression chambers 61a and 61b are communicated with the first compression chambers 61a and 61b by an injection passage 74 formed by injection holes 52a and 52b having a small diameter, and an oil groove 291 provided in the thrust bearing 220 is intermittently opened and closed by a lap support disk 218c. Is done.

In FIG. 15, the horizontal axis represents the rotation angle of the drive shaft 4, the vertical axis represents the refrigerant pressure, the pressure change state of the refrigerant gas during the suction, compression and discharge processes, and the solid line 62 operates at normal pressure. A point 63 indicates a pressure change at the time of abnormal pressure rise.

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

1 to 15, when the drive shaft 204 is rotationally driven by the motor 3, the orbiting scroll 218 is rotated.
Is driven by the crank mechanism of the drive shaft 204.
Of the Oldham ring 24
The key portion on the side of the orbiting scroll 218 (see FIG. 2) is engaged with the key groove 71 of the orbiting scroll 218, and the key portion on the opposite side is the key groove 71a on the main body frame 205 (see FIG. 1).
Therefore, the rotation is prevented, the orbital motion is made, and the volume of the compression chamber is changed together with the fixed scroll 15, thereby performing the suction / compression operation of the refrigerant gas.

The release gap 27 on the back side of the thrust bearing 220, which communicates with the compression chamber in the final compression stroke (the compression space immediately before the compression chamber communicates with the discharge port 16), is filled with high-pressure refrigerant gas as time elapses immediately after the start of compression. Will be charged. Due to the back pressure and the elastic force of the seal ring 70, the thrust bearing 220 is attached to the end surface 1 of the fixed scroll 15.
5b1. Thereby, the orbiting scroll 2
The lap support disk 218c is sandwiched between the end face sliding surface 15b2 and the thrust bearing 220 (an assembly gap of 15 to 20 microns).

Then, from the refrigerating cycle connected to the compressor, the suction refrigerant of the gas-liquid mixture containing the lubricating oil flows from the suction pipe 47 into the accumulator chamber 46, and the fixed scroll 1
After colliding with the outer surface of the end plate 15b, the air flows into the suction chamber 17 through two suction holes 43 (see FIG. 14) through the space above the accumulator chamber 46.

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 the change of the inflow direction are once collected at the bottom of the accumulator chamber 46, and the suction refrigerant gas flows into 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 suction refrigerant gas separated into gas and liquid is supplied to the suction chamber 1
7. First compression chambers 61a, 61b formed between orbiting scroll 218 and fixed scroll 15 (see FIG. 14)
Through the second compression chambers 51a, 51
1b, and sequentially transferred to the third compression chambers 60a and 60b, and then discharged from the central discharge port 16 to the check valve chamber 50a, where the discharge chamber 2, the gas passage B80b, and the gas passage A80 are discharged.
a, and is discharged to the motor chamber 6 via the discharge chamber 2b in order.

When the compression chamber and the discharge port 16 are opened immediately after the completion of the compression, the compressed refrigerant gas undergoes a rapid primary expansion when flowing into the check valve chamber 50a from the compression chamber, and the discharge immediately thereafter is performed. During the period from the completion stroke to the compression completion stroke, the refrigerant gas discharged from the check valve chamber 50a temporarily flows back to the compression chamber.

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 constituting 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 80 disposed at the symmetric positions are merged in the discharge chamber 2b and the motor chamber 6, so that the discharge gas pulsation from each discharge passage 80 is attenuated. Due to the fourth-order expansion, the pressure is further attenuated and the pressure in the motor chamber 6 hardly fluctuates.

When the discharged refrigerant gas flows backward from the discharge chamber 2 to the check valve chamber 50a instantaneously, the valve body 50b tries to move in the direction of closing the discharge port 16 following the flow. During operation of the machine, the coil spring 50c having the shape memory characteristic is completely contracted due to the ambient temperature and does not exert an urging force on the valve body 50b, and the magnetic valve body 50b is attracted to the bottom surface of the check valve chamber 50a. And the valve body 50b
Does not block the discharge port 16.

The refrigerant gas discharged from the small holes 81a of the discharge guide 81 and discharged into the motor chamber 6 is supplied to the annular closing plate 8
6, after colliding with the windings of the motor 3, flows through the cooling passage 35 on the outside of the stator 3b and the passage on the inside to the upper side of the motor chamber 6 while cooling the motor 3; To the refrigeration cycle.

At this time, a part of the lubricating oil in the discharged refrigerant gas adheres to the surface of the lower winding of the motor 3 and is separated from the refrigerant gas and collected in the discharge chamber oil reservoir 34. The lubricating oil in the discharged refrigerant gas passing through the outer periphery of the weight 75 and the lower balance weight 76 is centrifugally separated by the rotation of the upper balance weight 75 and the lower balance weight 76 and diffused to the inner surface of the winding of the motor 3. ,
It flows down to the lower part along the internal space of the winding bundle, and the discharge chamber oil reservoir 3
Collect at 4.

The lubricating oil in the discharge chamber oil reservoir 34 is supplied to the oil chamber A 278a, the oil chamber B 278b, and the back pressure chamber 2 via a path described later.
39, and the back pressure applying force to the orbiting scroll 218 gradually increases.

Following the pressure increase in the motor chamber 6, the lap support disk 218c gradually comes into contact with the end plate sliding surface 15b2 of the fixed scroll 15 with an appropriate pressing force. There is no gap between the tip of the fixed scroll wrap 15a and the wrap support disk 218c of the orbiting scroll 218, whereby the compression chamber is sealed, the suction refrigerant gas is efficiently compressed, and stable operation is continued.

The axial gap between the tip of the orbiting scroll wrap 218a and the end plate 15b of the fixed scroll 15 is formed in the tip seal groove 98 (see FIG. 7) when the refrigerant gas during compression leaks to the adjacent low pressure side compression chamber. 3), and the tip seal 98a is pressed against the side face of the low compression chamber of the tip seal groove 98a and the end plate 15b of the fixed scroll 15 by the gas back pressure to be sealed.

When the compressor is stopped, the orbiting scroll 218 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, The orbiting scroll 218 is shown in FIG.
As shown in FIG. 4, the first compression chambers 61 a and 61 b stop at the turning angle in a state where the first compression chambers 61 a and 61 b communicate with the suction chamber 17.

Further, when the compressor is stopped, the refrigerant gas in the compression chamber flows back to the suction chamber 17 so that the pressure of the refrigerant gas in the discharge port 16 rapidly drops, 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.

Due to the temporary reverse flow of the discharged refrigerant gas immediately after the compressor is stopped and the reverse rotation of the orbiting scroll 218, the magnetic valve element 50b is separated from the bottom surface of the check valve chamber 50a.
Until the refrigerating cycle balances the pressure, the valve body 51b keeps closing the discharge port 16 due to the pressure difference. At the same time, the temperature of the coil spring 50 having the shape memory characteristic decreases and the coil spring 50 expands.
0b keeps closing the discharge port 16.

The first compression chambers 61a and 61b, which intermittently communicate with the suction chamber 17, and the back pressure chamber 39 are composed of the first compression chambers 61a and 61a.
Oil groove 291 provided in thrust bearing 220 only when 1b is within 180 degrees before closing is completed (see FIG. 13)
And the space between the thrust bearing 220 and the lap support disk 218c is sealed with a lubricating oil film, so that the refrigerant gas does not flow backward from the compression chamber to the back pressure chamber 239 during compression.

When the compressor is stopped for a long time, the pressure in the compressor is balanced, and the liquid refrigerant flows into the accumulator chamber 46 as well as into the compression chamber. A thrust force in the direction opposite to the discharge port 16 acts on the orbiting scroll 218 by the pressure of the liquid compressed refrigerant in the compression chamber. As a result, the orbiting scroll 218 is separated from the fixed scroll 15 in the axial direction, and the compression load is reduced.

On the other hand, the back pressure chamber 239 in the early 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 218c of the orbiting scroll 218 is separated from the end plate sliding surface 15b2 in a state where the back pressure is applied only by the lubricating oil in the oil chamber A278a with a low pressure rise, and the thrust bearing 22
0, and is supported by a gap between the wrap support disk 218c and the tip of the fixed scroll wrap 15a (approximately 0.0
15 to 0.020 microns), lowering the compression chamber pressure and reducing the compression load at the beginning of startup.

In the event that liquid compression or the like occurs in the compression chamber and the pressure in the compression chamber rises abnormally instantaneously during continuous operation, the thrust force acting on the orbiting scroll 218 is applied to the back of the orbiting scroll 218. The orbiting scroll 218 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 239 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,
Liquid compression does not occur within this communication swivel range. Therefore, in any compressor operating state including the occurrence of liquid compression in the compression chamber, the backflow of the refrigerant gas in the compression chamber to the back pressure chamber 239 is avoided, and the reduction of the compression load is not hindered.

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 241 provided on the drive shaft 204.
a, 241b, the oil hole A238
The oil is sucked into the oil chamber A 278a via the line a.

At this time, the partition cap 101 guides the lubricating oil so that it passes near the surface of the drive shaft 204 and flows into the oil chamber A 278a and the spiral oil groove 241b. As a result, when the lubricating oil flows into the oil chamber A 278a from the oil hole A 238a, the lubricating oil is sucked into the helical oil groove 241a without being affected by the centrifugal diffusion caused by the high speed rotation of the drive shaft 204, so that a good screw pump oil supply can be performed. Will be

Then, the lubricating oil in the oil chamber A 278a is supplied to the oil chamber B 278b after lubricating the sliding surface of the revolving bearing 218b through the spiral oil groove 241b, and is depressurized through the throttle passage 103, and is then depressurized. While flowing into the back pressure chamber 239 via the hole 105, it is sequentially supplied to the sliding surfaces of the main bearing 212, the upper bearing 211, and the thrust bearing portion 213 by the screw pump action of the spiral oil groove 241 a, and the discharge chamber oil sump is provided. Return to 34.

Incidentally, the refrigerant gas in the motor chamber 6 is prevented from flowing back to the oil sump 72 by the lubricating oil passing through the upper bearing 211.

The refrigerant gas pressure discharged from the motor chamber 6 rises following the passage of time after the cold start of the compressor, and the discharge chamber oil reservoir 34
The lubricating oil of the oil chamber A
The oil is supplied to the back pressure chamber 239 together with the screw pump action of the spiral oil groove 241b. Back pressure chamber 239
Gradually increases, and a combined force with the lubricating oil pressure equivalent to the discharge pressure of the oil chamber A 278a acts on the lap support disk 218c of the orbiting scroll 218. As a result, the thrust load acting to separate the orbiting scroll 218 from the fixed scroll 15 is canceled by the refrigerant gas pressure in the compression chamber, and the thrust force acting on the orbiting scroll 218 is reduced.

Accordingly, while the pressure increase in the motor chamber 6 after the cold start of the compressor is low, the oil chamber A 278a and the back pressure chamber 23
9, the force applied to the orbiting scroll 218 by the lubricating oil pressure is smaller than the thrust load on the orbiting scroll 218 by the refrigerant gas pressure in the compression chamber. As a result, the orbiting scroll 218 separates from the fixed scroll 15 and is supported by the thrust bearing 220 which receives the elastic force of the seal ring 70 and the back pressure due to the refrigerant gas introduced from the compression chamber in the final compression stroke.

When the pressure difference between the discharge pressure and the suction pressure exceeds the required pressure, the force applied to the orbiting scroll 218 by the lubricating oil pressure in the oil chamber A 278a and the back pressure chamber 239 is changed by the orbiting scroll by the refrigerant gas pressure in the compression chamber. 218 is greater than the thrust load. The orbiting scroll 218 is supported by the fixed scroll 15.

The center of the compression chamber, the center of the slewing bearing 218e,
In the arrangement in which the centers of the annular rings 94 are substantially coincident with each other, the annular ring 94 orbits together with the orbiting scroll 218, so that the annular ring 94 tends to jump out of the annular seal groove 95 provided in the orbiting boss portion 218e by the inertial force at that time. . The annular ring 94 expands its inner diameter by the pressure difference between the oil chamber A 278a and the back pressure chamber 239, 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 205 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.
To prevent excessive leakage of lubricating oil from oil chamber A 278a to back pressure chamber 239.

Further, the resin-made annular ring 94 having excellent flexibility expands its inner diameter along the outer side surface of the annular seal groove 95 due to the pressure difference between the back pressure chamber 239 and the oil chamber A 278a, so that heat is removed. 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 member and the body frame 205, wear and sliding resistance of the sliding surface are reduced.

During the normal operation of the compressor, the high-pressure oil chamber A 278
The orbiting scroll 218 is provided with a back pressure on the fixed scroll 15 side by the lubricating oil pressure of a and the lubricating oil pressure of the back pressure chamber 239, and the lap support disk 218c and the end plate sliding surface 15b2
, Smoothly slides while maintaining an appropriate contact force, thereby minimizing the axial gap of the compression chamber.

The lubricating oil flowing into the back pressure chamber 239 intermittently flows into the outer peripheral space 37 via an oil groove 291 provided in the thrust bearing 220, and further flows into the lap support disk 218c.
, The pressure is gradually reduced through an oil hole C38c provided in the nozzle and small-diameter injection holes 52a and 52b (see FIG. 14).
It flows into the first compression chambers 61a and 61b. The lubricating oil lubricates each sliding surface in the middle of the passage and seals the sliding gap.

The lubricating oil injected into the first compression chambers 61a and 61b merges with the lubricating oil flowing into the compression chamber (compression space) together with the suctioned refrigerant gas, and seals a minute gap between adjacent compression chambers with an oil film. The compressed refrigerant gas is discharged again to the motor chamber 6 through the discharge port 16 together with the compressed refrigerant gas while preventing the leakage of the compressed refrigerant gas and lubricating the sliding surfaces between the compression chambers.

In the oil supply path from the discharge chamber oil reservoir 34 via the back pressure chamber 239 to the first compression chambers 61a and 61b,
The back pressure chamber 239 maintains a proper 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, the orbiting scroll 2
18 separates from the fixed scroll 15 and the thrust bearing 2
20 supported.

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 decrease the release gap 27, and is fixed to the wrap support disk 218c of the orbiting scroll 218. The axial gap between the scroll 15 and the tip of the fixed scroll wrap 15a 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 dashed line 63a in FIG.

The orbiting scroll 218 is the fixed scroll 1
5 is restricted to about 70 microns in the axial direction, an oil film remains in each gap between the sliding surfaces on both sides of the lap support disk 218c, and the outer peripheral space 37 and the suction chamber 1
7, the pressure change in the back pressure chamber 239 due to the direct communication with the thrust bearing is suppressed, and after 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 218 retreats toward the thrust bearing 220, the orbiting scroll wrap 21
The axial dimension between the tip of the fixed scroll 15 and the tip of the fixed scroll 15 also increases, but since the tip seal 98a is pressed against the fixed scroll 15 by the gas pressure on the back surface thereof,
Almost no compressed refrigerant gas leaks from this part.

On the other hand, the gap between the wrap support disk 218c of the orbiting scroll 218 and the tip of the fixed scroll wrap 15b of the fixed scroll 15 is enlarged, and compressed refrigerant gas leaks in the compression chamber, and the pressure in the compression chamber suddenly increases. descend.

Also, when foreign matter is caught in the axial gap between the orbiting scroll 218 and the fixed scroll 15, the thrust bearing 20 retreats and removes the foreign matter, as described above.

In the initial stage of cold start or during steady-state operation, the pressure in the compression chamber when instantaneous liquid compression occurs 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 2b, the expansion is repeated while passing sequentially, and the pressure in the motor chamber 6 hardly changes.

Further, as the operating speed of the compressor increases, the leakage of the refrigerant gas from the compression chamber per unit time decreases. On the other hand, the injection holes 52a, 52 per one turning motion
The opening time of b is shortened, the amount of oil injection into the compression chamber per one swiveling motion is suppressed, and unnecessary oil compression is reduced.

In the above embodiment, the thrust bearing 220
Although the compressed refrigerant gas during the final compression stroke is introduced into the release gap 27 provided on the back surface of the compressor, the discharged refrigerant gas in a region where the compression chamber and the discharge port 16 communicate with each other in the final compression stroke may be introduced into the release gap 27. .

In the above embodiment, the orbiting scroll 21
8, the sliding gap between the lap support disk 218c and the thrust bearing 220 was sealed only with the oil film of the lubricating oil, but the annular ring as proposed by the inventor in Japanese Patent Application No. 63-159996 was used. It may be mounted on the back side of the lap support disk 218c to improve the sealing performance of the sliding gap between the back pressure chamber 239 and the outer peripheral space 37.

The injection holes 52 communicating with the first compression chambers 61a and 61b intermittently communicating with the suction chamber 17 are provided.
a, 52b, the back pressure chamber 2
The pressure at 39 may be set to an intermediate pressure close to the suction pressure.

In the above-described embodiment, the annular ring 94 is provided in the annular seal groove 95 provided in the orbiting boss 218e of the orbiting scroll 218.
As described in Japanese Patent Publication No. 8396, when the annular seal groove and the annular ring are provided in the main body frame 205, the same operation as described above is performed.

As described above, according to the above embodiment, the effects of the following embodiments can be obtained.

That is, in the first embodiment, the scroll compression mechanism is accommodated in the lower part of
The motor 3 connected to 4 is housed in the upper part of the closed case 1,
After the discharged refrigerant gas discharged from the discharge port 16 cools the motor 3, a discharged refrigerant gas passage that is discharged to the outside of the closed case 1 is provided, and the discharge chamber oil reservoir 34 on which the discharge pressure acts is provided below the motor 3 and The drive shaft 204 is supported and arranged at a considerable height from the main bearing 212 on the side close to the compression chamber.
04 and orbiting scroll 21 that orbiting scroll 218 engages
In a configuration in which a differential pressure oil supply passage for supplying lubricating oil from the discharge chamber oil reservoir 34 is provided in the first compression chambers 61a and 61b via the sliding portion 8b and the anti-compression side of the orbiting scroll 218, the drive shaft 204 is The oil chamber A 278a, which is arranged inside the thrust bearing 202 provided on the main body frame 205 to be supported and is arranged adjacent to the main bearing 212, the slewing bearing 218b, and the lap support disk 218c, is located in the middle of the differential pressure oil supply passage. The lubricating oil in the oil chamber A 278a branches from the differential pressure oil supply passage by the screw pump action of the spiral oil groove 241a provided on the sliding surface of the main bearing 212 and discharges the oil in the discharge chamber oil reservoir 34.
And a bearing oil supply passage for returning the oil to the bearing.

According to this structure, the discharge chamber oil sump 34
When the lubricating oil is introduced into the oil chamber A 275a by the pump action of the spiral oil groove 241a, the first compression chamber 61
The lubricating oil is introduced into the oil chamber A 278a easily with the aid of the suction effect due to the pressure difference between the a and 61b, the required amount of pump oil can be easily secured during low speed to high speed operation, and the pump oil passage is short. Therefore, the pump input of the screw pump mechanism by the spiral oil groove 241a can be extremely reduced.
Further, the lubricating oil in the oil chamber A 278 a is supplied to the orbiting scroll 218.
, The thrust force acting on the orbiting scroll 218 can be reduced, and the frictional resistance of the sliding surface of the orbiting scroll 218 in the axial direction can be reduced.

In the second embodiment, a thrust bearing 213 supporting the weight of the drive shaft 204 and the rotor 3a of the motor 3 is provided.
Are arranged in the middle of the bearing oil supply passage. According to this configuration, it is possible to reduce the thermal harm caused by the lubricating oil whose temperature has increased in the thrust bearing portion 213 flowing into the first compression chambers 61a and 61b.

In the third embodiment, the thrust bearing 21
3 is disposed at the end of the bearing oil supply passage. According to this configuration, the lubricating oil whose temperature has risen in the thrust bearing portion 213 does not flow into the first compression chambers 61a and 61b.
The adverse effect on the lubrication performance can also be avoided.

(Embodiment 2) FIG. 16 is a longitudinal sectional view of a scroll refrigerant compressor according to a second embodiment of the present invention.
4 and the scroll compressor groove, and the motor 3 is arranged on the upper part.

The suction chamber 17 is provided with a closed case 2001 made of iron.
Through a suction pipe 2047 passing through the side wall of the compressor.

The main body frame 2005 made of cast iron fixes the fixed scroll 2015 and the closed case 200.
One side wall is fixed by welding at several places.

The drive shaft 2004 connected to the motor 3 is connected to the main bearing 2012 on the side closer to the compression portion of the main body frame 2005.
And the upper bearing 2011 on the side of the motor.
The crankshaft 2014 is slidably connected to the orbiting bearing 2018b of the orbiting scroll 2018.

The discharge chamber oil reservoir 2034 is
05 and an oil suction passage 2038 provided in the fixed scroll 2015, and communicates with an oil chamber A 2078 a on the compression chamber side of the main bearing 2012.

Crankshaft 2014 and swing bearing 2018b
Is formed in the orbiting scroll 2
218 of the turning boss portion 2018e
0 to the back pressure chamber 2039 and the slewing bearing 2
It communicates with the oil chamber A2078a through the sliding gap of the portion 018b.

The outer peripheral space 20 of the orbiting scroll 2018
37 and the back pressure chamber 2039, the Oldham ring 202
Key groove 2071 of the orbiting scroll 2018 which engages with No. 4
The first compression chambers 61 a and 61 b (see FIG. 14) are configured to intermittently communicate with each other only while communicating with the suction chamber 17 via an oil groove 291 provided in the thrust bearing 220.

Oil groove 291 and key groove 2 provided at two locations
Numerals 071a are arranged at opposite positions, and are intermittently connected between the back pressure chamber 2039 and the outer peripheral space 2037 at a phase angle of 180 degrees.

The other configuration is similar to that of the first embodiment, and the description is omitted. Next, the operation of this embodiment will be described.

The lubricating oil in the discharge chamber oil reservoir 2034 flows into the compression chamber via the following differential pressure path due to the pressure difference between the discharge chamber oil reservoir 2034 on which the discharge pressure acts and the compression chamber. The lubrication of the sliding portion, the back pressure bias for pressing the orbiting scroll 2018 toward the fixed scroll 2015, and the oil film sealing for preventing gas leakage in the gap of the sliding portion are provided.

That is, the lubricating oil in the discharge chamber oil reservoir 2034 is supplied to the oil chamber A2 through the oil suction passage 2038 provided in the main body frame 2005 and the fixed scroll 2015.
078a.

The lubricating oil in the oil chamber A 2078a
The main bearing 2012,
While being supplied to the upper bearing 2011, the crankshaft 2
The primary pressure is reduced through the bearing gap between the rotary bearing 2018 and the slewing bearing 2018b, flows into the oil chamber B2078b, and flows into the small hole 204.
After the pressure is reduced to a second level through 0, the pressure flows into the back pressure chamber 2039.

The openings into the back pressure chamber 2039 of the small holes 2040 provided at the two positions of the revolving boss portion 2018e are in the vicinity of the key groove 2071a of the engagement sliding portion between the Oldham ring 2024 and the main body frame 2005. And the lubricating oil flowing from the oil chamber B 2078b into the back pressure chamber 2039 is
The sliding surface of the key groove 2071a is forcibly lubricated.

The lubricating oil in the back pressure chamber 2039 passes through two key grooves 2071 provided in the orbiting scroll 2018 and two shallow grooves 291 provided in the thrust groove receiver 220, and slides in the key grooves 2071. A 180 ° phase angle is formed while lubricating the surface, and the air is intermittently tertiarily decompressed and flows into the outer peripheral space 2037 from opposite positions.

The lubricating oil inflow path from the outer peripheral space 2037 to the compression chamber is the same as in the first embodiment.

Due to the pressure difference between the oil chamber A 2078a and the oil chamber B 2078b, the drive shaft 2004 comes into contact with the end face of the orbiting boss 2018e of the orbiting scroll 2018 and is slidably supported.

Fixed scroll 2015 and body frame 2
The outer surface of the connection surface with the refrigerant 005 is surrounded by the lubricating oil of the discharge chamber oil reservoir 2034, and the refrigerant gas on the high pressure side flows into the outer peripheral space 2037 through the connection surface and is confined in the connection surface. Since the blocked oil film prevents the high-pressure refrigerant gas from flowing into the outer peripheral space 2037.

The refrigerant gas flowing into the suction chamber 17 via the suction pipe 2047 is compressed and then discharged to the discharge chamber 2.
After being discharged to the discharge chamber 2002b through two discharge passages 2080 provided at symmetric positions, the motor chamber 200
6 and is sent from the discharge pipe 2031 to an external refrigeration cycle.

The discharge passage 20 provided at the symmetric position
The pressure pulsation and the discharge sound of the discharged refrigerant gas discharged from the discharge chamber 80 to the discharge chamber 2002b interfere with each other and attenuate. Thereafter, the pressure pulsation is similarly discharged again from the discharge chamber 2002b to the motor chamber 2006 in the same manner. Attenuated. As a result, the motor room 200 communicating with the external piping system
The pressure fluctuation of 6 is attenuated to such an extent that it does not affect the vibration of the external piping system.

Further, the compressed refrigerant gas flows from the compression chamber to the discharge chamber 2.
Is discharged by the lubricating oil in the discharge chamber oil reservoir 2034 surrounding the compression chamber and the discharge chamber 2, and is less likely to be transmitted to the outside of the closed case 2001.

Further, the compressed refrigerant gas flows from the compression chamber to the discharge chamber 2.
The discharge sound at the time of discharge to the compressor increases following the compressor operating speed.
600 rpm) or less, the discharge chamber 200
In some cases, the discharge refrigerant gas is directly discharged from the two discharge passages 2080 provided at symmetrical positions to the motor chamber 2006 without using 2b.

Although the first and second embodiments have been described, these embodiments may be appropriately combined according to the operating conditions of the compressor.

In the above embodiment, the lubricating oil in the back pressure chamber flows into the first compression chambers 61a and 61b. However, the other compression chambers (such as the operating speed and the compression load) are operated in accordance with the compressor operating conditions (operating speed, compression load, etc.). An oil supply passage that flows into the suction chamber 17 or a compression chamber that does not communicate with the discharge port 16) may be formed. When the oil supply passage for flowing into the suction chamber 17 is configured, the pressure of the back pressure chamber can be set to a pressure close to the suction pressure.

As described above, according to the above-described embodiment, the scroll compression mechanism is housed in the lower part of the closed case 2001, and the motor 3 connected to the drive shaft 2004 is closed.
After the discharge refrigerant gas discharged from the discharge port 16 cools the motor 3, a discharge refrigerant gas passage that is discharged to the outside of the closed case 2001 is provided, and the discharge chamber oil reservoir 2034 on which discharge pressure acts is provided. The drive shaft 2004 and the main bearing 2012 on the side close to the compression chamber are arranged at a considerable height, and the sliding portion of the orbiting bearing 2018 b in which the drive shaft 2004 and the orbiting scroll 2018 are engaged with the orbiting scroll 20.
18, the first compression chambers 61a, 61b
Is provided inside a thrust bearing 202 provided in a main body frame 2005 supporting a drive shaft 2004, and a main bearing 2012 and a slewing bearing are provided. 2018b
A oil chamber A2078a partitioned and arranged adjacent to the wrap support disk 2018c is disposed in the middle of the differential pressure oil supply passage, and a helical oil groove 2041a provided on the sliding surface of the main bearing 2012
A bearing oil supply passage for returning the lubricating oil in the oil chamber A2078a to the discharge chamber oil reservoir 2034 by the pumping action of According to this configuration, the discharge chamber oil sump 2
When the lubricating oil No. 034 is introduced into the oil chamber A2075a by the pumping action of the spiral oil groove 2041a, the oil chamber is supported by the self-weight of the lubricating oil and the suction action by the pressure difference between the first compression chambers 61a and 61b. The introduction of lubricating oil into the A2078a is facilitated, the required amount of pump oil to be supplied during low-speed to high-speed operation can be easily ensured, and the resistance of the pump oil supply passage is reduced. Can be extremely low.

Further, the lubricating oil in the oil chamber A2078a urges the anti-compression side of the orbiting scroll 2018 to reduce the thrust force acting on the orbiting scroll 2018, and reduces the frictional resistance of the axial sliding contact surface of the orbiting scroll 2018. It can be reduced.

(Embodiment 3) FIG. 17 is a longitudinal sectional view of a scroll refrigerant compressor according to a third embodiment of the present invention. Inside of a sealed case 801 made of soft iron is similar to that of FIG. An upper sealed case 801a and a lower sealed case 801b are partitioned by a main body frame 805 supporting a shaft 704. The inside of the upper sealed case 801a is a high-pressure space in which a motor 703 is built, and the lower sealed case 801
The inside of b constitutes an accumulator chamber 846 with a low-pressure space communicating with the downstream side of the evaporator.

The driving shaft 704 for connecting the motor 703 is
The main bearing 8 of the main body frame 805 from the side of the motor chamber 806
12 and supported by a main bearing 812 and an upper frame (not shown).

The discharge chamber 2 is connected to the high pressure side via a gas passage B 880b provided in the fixed scroll 815, a gas passage A 880a provided in the main frame 805, and a discharge chamber 2c formed by the main frame 805 and the discharge guide 81. Of the motor room 806.

[0135] A discharge pipe (not shown) provided at the upper end of the upper sealed case 801a communicates with the motor chamber 806.

The spiral oil groove 841 provided on the drive shaft 704
a and the screw pump action of the spiral oil groove 841b,
The lubricating oil in the discharge chamber oil reservoir 34 is divided into an oil chamber A878a and an oil chamber A87.
An oil supply passage is provided to be introduced into 8b. The lubricating oil in the oil chamber A 878b is reduced in pressure through the small hole 2040a provided in the lap support disk 818c of the orbiting scroll 818 and flows into the back pressure chamber 839, while the main bearing 812
To the main bearing 8 through the spiral oil groove 841a.
After merging with the lubricating oil supplied to the motor 12, a bearing oil supply passage that returns to the discharge chamber oil reservoir 34 through a thrust bearing portion 813 that supports the weight of the rotor 703 a of the motor 703 and the drive shaft 704 is formed.

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 compression, and the end faces of the coil springs 131 are held down by a discharge guide 881 attached to the main body frame 805. 220 is the end plate 815b of the fixed scroll 815
Is pressed.

The rear side of the thrust bearing 220 communicates with the discharge chamber oil reservoir 34 by 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 inside, and on the outer side,
The thrust bearing 220 is sealed by pressing against the end plate 815b.

The outer peripheral space 37 of the orbiting scroll 818
Communicates intermittently with the back pressure chamber 839 via a shallow groove 891 provided in the thrust bearing 220,
The end plate 818b communicates with the suction chamber 17 via an oil groove 899 provided on the sliding surface of the end plate 818b.

According to this embodiment, the back pressure chamber 83
9 holds the suction chamber 17 and a considerable pressure.

Therefore, the application of the back pressure to the orbiting scroll 818 acting on the fixed scroll 815 depends only on the lubricating oil pressure in the oil chamber A 878a.

According to the back pressure application mode and the differential pressure oil supply path mode, the oil chamber A 878a and the oil chamber B
The lubricating oil in the discharge chamber oil reservoir 34 can be supplied to 878b, and oil can be easily supplied to the sliding surface of the bearing adjacent thereto even during extremely low speed operation of the compressor.

In the above embodiment, the main bearing 212 and the slewing bearing 218b are arranged adjacent to each other in the main shaft direction of the drive shaft 204. However, Japanese Patent Application Laid-Open Nos.
As shown in JP-A-205490, it is clear that the same operation and effect as described above can be expected even in the case of the configuration in which the slewing bearing is arranged inside the main bearing.

In the above embodiment, the refrigerant compressor has been described. However, similar effects can be expected in the case of other gas compressors such as oxygen, nitrogen and helium using lubricating oil.

[0146]

As is apparent from the above embodiment, the first aspect of the present invention provides a scroll compression mechanism in a closed case.
The motor that is housed in the lower part of the
Gas discharged from the discharge port
Discharge air discharged outside the sealed case after cooling
A body passage is provided and the oil level of the discharge chamber
It is located at the lower part of the motor and at the same height as the upper end of the main bearing,
The sliding part of the slewing bearing and the back of the lap support disk on the side opposite the compression chamber
Via one of the compression chambers and the suction chamber
In a configuration in which a differential pressure oil supply passage for supplying lubricating oil is provided,
The main bearing and the slewing bearing are arranged inside the thrust bearing.
The discharge pressure partitioned adjacent to the lap support disk is
The working oil chamber is located in the middle of the differential pressure
By a spiral oil groove provided throughout the sliding surface in the axial direction
Lubricating oil from oil chamber in discharge chamber to oil chamber by screw pump
And divert part of the lubricating oil to the differential pressure oil supply passage
Meanwhile, most of the remaining lubricating oil is returned to the discharge chamber sump.
A bearing oil supply passage is formed.
Spiral oil in the sump oil sump is supplied by a spiral oil groove with a small lift capacity.
When the lubricating oil is introduced into the oil chamber by
Of the suction action due to the pressure difference between the pressure and the compression chamber (or suction chamber)
With support, lubricating oil can be easily introduced into the oil chamber,
At the time of low speed to high speed operation to the main bearing that supports most of the load
It is easy to secure the required amount of pump lubrication.
Road resistance is reduced, reducing friction loss and durability of the main bearing
Of screw pump mechanism with improved oiliness and spiral oil groove
The input power can be extremely low. Also, the lubricating oil in the oil chamber urges the anti-compression side of the orbiting scroll to reduce the thrust force acting on the orbiting scroll, thereby reducing the frictional resistance of the orbiting scroll in the axial sliding contact surface, and improving the pump operation effect. The synergistic effect of reducing compressor input and improving durability can be achieved.

According to a second aspect of the present invention, there is provided another helical shaft provided on the sliding surface of the drive shaft in the middle of the bearing oil supply passage downstream of the helical oil groove provided on the sliding surface of the main bearing. Screw pump means with oil grooves of at least
The thrust bearing that supports the screw pump means on the discharge side
According to this configuration, a simple screw
Function to provide sufficient lubrication to the thrust bearing
And reduce the adverse effects caused by the lubricating oil whose temperature has risen in the thrust bearing part flowing into the compression chamber.
This has the effect of preventing a decrease in compression efficiency.

According to the third aspect of the present invention, the thrust bearing is disposed at the end of the bearing oil supply passage. According to this configuration, the lubricating oil whose temperature has increased in the thrust bearing flows into the compression chamber. In addition to avoiding the adverse effects, it is also possible to avoid the adverse effects on the lubrication performance of the main bearing, thereby preventing a decrease in the compression efficiency and improving the durability of the bearing sliding portion.

[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 a main part of the check valve device.

FIG. 6 is a perspective view of a main part 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 partition cap and bearing parts in the compressor.

FIG. 10 is a perspective view of the partition cap and bearing parts.

FIG. 11 is a perspective view of a sealing part in the compressor.

FIG. 12 is a perspective view of a thrust bearing in the compressor.

FIG. 13 is a partial cross-sectional view of a thrust bearing portion of the compressor.

FIG. 14 is a cross-sectional view taken along line AA in FIG. 1;

FIG. 15 is a characteristic diagram showing a change in pressure of refrigerant gas from a suction stroke to a discharge stroke of the compressor.

FIG. 16 is a longitudinal sectional view of a scroll refrigerant compressor according to a second embodiment of the present invention.

FIG. 17 is a longitudinal sectional view of a scroll refrigerant compressor showing a third embodiment of the present invention.

FIG. 18 is a longitudinal sectional view of a conventional scroll compressor.

FIG. 19 is a longitudinal sectional view of another conventional scroll compressor.

[Explanation of symbols]

 Reference Signs List 1 Closed case 15 Fixed scroll 15a Fixed scroll wrap 15b End plate 16 Discharge port 17 Suction chamber 24 Rotation prevention mechanism 34 Discharge chamber oil sump 60a Third compression chamber 204 Drive shaft 205 Main frame 212 Main bearing 218 Turning scroll 218a Turning scroll wrap 218b Turning Bearing 218c Lapping support disk 220 Thrust bearing 241a, 241b Oil groove 278a Oil chamber A 278b Oil chamber B 213 Thrust bearing

Claims (3)

(57) [Claims] An orbiting scroll wrap on a wrap supporting disk forming a part of a orbiting scroll is rotatably engaged with a spiral fixed scroll wrap formed on one surface of a head plate forming a part of a fixed scroll. In addition, a spiral 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, and a suction chamber is provided outside the fixed scroll wrap. Is divided into a plurality of compression chambers which continuously shift from the suction side to the discharge side, so that the wrap support disk supports the head plate and the main shaft on the side near the compression chamber that supports the drive shaft and compresses the fluid. The lap support disk and the main frame are disposed between a main frame having a bearing and a thrust bearing for supporting the anti-compression chamber side of the lap support disk. A scroll compression mechanism that engages the rotation preventing member of the orbiting scroll between the drive shaft and the orbiting scroll via a orbiting bearing that engages with the drive shaft and the orbiting scroll wrap; The scroll compression mechanism is stored in the lower part of the closed case,
A motor connected to the drive shaft is housed in the upper part of the closed case, and a discharge gas passage is provided to discharge the gas discharged from the discharge port to the outside of the closed case after cooling the motor. oil in the discharge chamber oil reservoir but to act
A surface is disposed at a substantial height below the motor and at an upper end of the main bearing , and a sliding portion of the slewing bearing and the lap support circle
In a configuration in which a differential pressure oil supply passage for supplying lubricating oil from the discharge chamber oil reservoir is provided in one of the compression chamber and the suction chamber via a rear surface of the plate opposite to the compression chamber, inside the thrust bearing The discharge pressures arranged and arranged adjacent to the main bearing, the slewing bearing, and the lap support disk are formed.
An oil chamber to be used is disposed in the middle of the differential pressure oil supply passage, and the oil chamber is provided from the discharge chamber oil reservoir by a screw pump action of a spiral oil groove provided over the entire sliding surface of the main bearing in the axial direction.
Lubricating oil is introduced into the oil storage chamber, and a part of the lubricating oil
A scroll gas compressor having a bearing oil supply passage that branches to an oil supply passage and returns most of the remaining lubricating oil to the discharge chamber oil reservoir. 2. A spiral oil groove provided on a sliding surface of a main bearing.
On the sliding surface of the drive shaft in the bearing oil supply passage
2. The scroll gas compressor according to claim 1, further comprising a screw pump means formed by a separate spiral oil groove, and a thrust bearing portion for supporting at least the weight of the drive shaft and the motor on the discharge side of the screw pump means. 3. The scroll gas compressor according to claim 1, wherein the thrust bearing is disposed at an end of the bearing oil supply passage.