JPH06100184B2 - Scroll gas compressor - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll gas compressor having a built-in accumulator device.

2. Description of the Related Art A scroll compressor has a suction chamber on the outer periphery and a discharge port provided at the center of the spiral, and is sucked and compressed in a symmetrical spiral compression space centered on the discharge port, causing the flow of compressed fluid. However, it is generally known that the fluctuation of the compression torque in one direction is smaller than that of the reciprocating compressor and the rotary compressor, and the vibration and noise are extremely small.

Further, generally, as shown in FIG.
When the refrigeration cycle is configured by sequentially connecting the 12, expansion valve 113, and evaporator 114, the suction refrigerant is accumulated and the compressor 111
In order to prevent the refrigerant liquid compression that tends to occur in the compression chamber of the compressor and improve the durability of the compressor, the suction side of the compressor 111 and the evaporator 114
Accumulator for refrigerant gas-liquid separation and refrigerant accumulation between
110 is provided, the accumulator 110 is attached near the side surface of the compressor 111, etc., and the heat insulation between the accumulator 110 and the compressor 111 is devised, and the compression efficiency is lowered by heating the intake refrigerant gas accompanying the heating of the accumulator 110. Are prevented.

Further, as shown in FIG. 16, the internal structure of the accumulator 110 has a baffle plate so that the refrigerant liquid returning from the evaporator 114 does not directly flow into the upper open end of the center pipe 104 connected to the suction side of the compressor 111. The device 103 is arranged at the upper end of the center pipe 104 so that the refrigerant passage constitutes a bypass route passing through the passage B (Japanese Utility Model Laid-Open No. 59-84378).

Accumulator 11 for such gas-liquid separation and refrigerant accumulation
When 0 is attached to the scroll refrigerant compressor with low vibration and noise, the scroll refrigerant compressor is vibrated by the vibration of the accumulator itself caused by the inflow liquid refrigerant colliding with the inner wall of the accumulator 110, and for weight reduction. However, there is a problem that the refrigerant collision sound is transmitted through the thinly formed body 101 and the low vibration and low noise characteristics peculiar to the scroll compressor are impaired.

Further, regardless of the structure of the compressor, there is a problem that the compressor and the accumulator have different structures, so that a large space for arranging the compressor and its accessories is required.

On the other hand, as a measure to solve the above problems,
As disclosed in Japanese Laid-Open Patent Publication No. 2518, a configuration in which a compressor has a built-in accumulator section for gas-liquid separation is also considered.

However, in the present invention, the wall area forming the accumulator portion is large, and further, because the suction refrigerant gas passes through the electric motor portion, the suction refrigerant gas absorbs heat and the compression efficiency is significantly reduced.

Further, a configuration of the scroll compressor shown in FIG. 17 is also considered.

In the figure, the scroll compression unit and the frame 2 are inside the closed container 206.
A low pressure chamber 206b is formed in the upper part and a high pressure chamber 206a is formed in the lower part, and the low pressure chamber 206b separates the refrigerant into gas and liquid, and sucks the refrigerant gas through a suction pipe 210 provided in the fixed scroll member 202. After being sucked into the compression chamber and discharging the compressed refrigerant gas to the high pressure chamber 206a through the outflow passage 211 provided in the fixed scroll member 202, the lubricating oil contained in the discharged refrigerant gas is separated, and the low pressure chamber 206b and the high pressure chamber 206a are separated. An O-ring 21 provided between the frame 209 and the hermetic container 206 for sealing
4 by reducing the heating of the low pressure chamber 206b to the liquid refrigerant 219 by the heat insulating material 213 made of Teflon attached to the upper surface of the fixed scroll member 202, and compression by integrating the gas-liquid separation chamber with the closed container. Attempts have been made to save space, reduce noise, and reduce vibration when installing the machine (JP-A-57-70984).

However, in the configuration shown in FIG. 17, since the low-pressure chamber 206b is disposed above the scroll compression unit, the outer peripheral portion of the liquid refrigerant 219 forms the high-pressure chamber 206a at a high temperature in the sealed container 206. Is in direct contact with. For this reason, there is a problem in that the suction refrigerant gas at the outer peripheral portion and the upper portion of the liquid refrigerant 219, which has a higher density than the refrigerant gas and has good heat conduction characteristics, is heated and the compression efficiency is reduced.

When the plate thickness of the portion of the closed vessel 206 forming the low-pressure chamber 206b is large, the suction refrigerant gas flows into the low-pressure chamber 206b and collides with the inner wall of the low-pressure chamber 206b.
Although the resonance sound of 206 does not propagate to the outside of the compressor, the sealed container 206
However, there is a problem in that the wall cross-sectional area becomes large, the amount of heat on the high-pressure chamber 206a side is easily transferred to the liquid refrigerant or the suction refrigerant gas, and the compression efficiency is further reduced.

On the contrary to the above, when the plate thickness of the portion of the closed container 206 forming the low pressure chamber 206b is thin, the refrigerant noise and the closed container 20
The resonance sound of 6 propagates to the outside of the compressor, and there is a problem in particular that the low noise characteristics of the scroll compressor are impaired.

Means for Solving the Problems In order to solve the above problems, the scroll compressor of the present invention stores a scroll compression mechanism in a hermetic container, and a high pressure chamber by a fixed scroll member in the hermetic container, and a gas-liquid of an intake fluid. Is divided into a low-pressure chamber for separating and accumulating, the low-pressure chamber is arranged in the lower part, the high-pressure chamber is arranged in the upper part, and the drive device related to the scroll compression mechanism is arranged in the high-pressure chamber, and most of the inner wall of the member forming the low-pressure chamber Is covered with a low natural frequency member made of a low specific gravity and soft material that has both heat insulation and soundproofing properties.

Effect of the Invention With the above structure, the present invention reduces heat transfer from the closed container forming the high pressure chamber of the compressor to the member covering the inner wall of the low pressure chamber, thereby reducing the heating of the suction liquid accumulated at the bottom of the low pressure chamber. However, the reduction of compression efficiency due to the built-in gas-liquid separation function and suction fluid accumulation function in the compressor is reduced.

Further, the gas-liquid mixed fluid flows into the low-pressure chamber to mitigate the sound generated when it collides with the inner wall of the low-pressure chamber and to reduce the propagation to the outside of the compressor.

Embodiment Hereinafter, a scroll refrigerant compressor according to an embodiment of the present invention will be described with reference to FIGS. 1 to 12.

In FIG. 1, reference numeral 1 denotes an iron hermetic case, the interior of which is partitioned into an upper motor chamber 6 and a lower accumulator chamber 46 by a fixed scroll member 15e which meshes with the orbiting scroll 18 to form a compression chamber. There is. The motor chamber 6 is under a high pressure atmosphere, the motor 3 is arranged in the upper part, the compression part is arranged in the lower part, and the main body frame 5 of the compression part which supports the drive shaft 4 fixed to the rotor 3a of the motor 3 is lightened and the bearing is It is made of an aluminum alloy with excellent heat conduction characteristics for the main purpose of heat dissipation of the parts, is fixed to the fixed scroll member 15e by bolts, and the iron liner 8 having excellent weldability is shrink-fitted and fixed to the outer peripheral part thereof. The outer peripheral surface of the liner 8 is inscribed in the entire circumference of the closed case 1 and is partially fixed by welding.

The stator 3b of the motor 3 is internally fixed to the closed case 1.

The drive shaft 4 is provided between an upper bearing 11 provided at the upper end of the main body frame 5, a main bearing 12 provided at the central portion, between the upper end surface of the main body frame 5 and the lower end surface of the rotor 3a of the motor 3. It is supported by the thrust ball bearing 13 and its lower end is
An eccentric bearing 14 is provided which is eccentric from the main shaft of the drive shaft 4.

The fixed scroll member 15e is composed of a fixed scroll 15 made of aluminum alloy, and a partition liner 79 made of iron and fitted to the outer periphery of the fixed scroll 15 by shrink fitting and having excellent weldability.

The fixed scroll 15 is a spiral fixed scroll wrap.
15a and an end plate 15b, and a discharge port 1 that is open at the winding start part of the fixed scroll wrap 15a at the center of the end plate 15b.
6 is provided so as to communicate with the discharge passage 80 open to the motor chamber 6, and the suction chamber 17 is provided on the outer peripheral portion of the fixed scroll wrap 15a.
Is provided.

Aluminum alloy composed of a spiral orbiting scroll wrap 18a that meshes with the fixed scroll wrap 15a to form a compression chamber, and a lap support disk 18c in which the orbiting shaft 18b supported by the eccentric bearing 14 of the drive shaft 4 is upright. The orbiting scroll 18 made of metal is arranged so as to be surrounded by the fixed scroll 15, the main body frame 5 and the drive shaft 4, and the wrap support disc 18 is provided.
The surface of c is hardened.

The discharge passage 80 includes a discharge gas guide 81 attached to the main body frame 5 and a gas passage A80 provided in the main body frame 5.
a, a gas passage B80b provided in the fixed scroll 15, and a gas passage C80c, and a gas passage C80c provided in a lateral direction and a gas passage provided in a lateral direction in communication with the discharge port 16.
A check valve device 50 is provided midway of the passage with B80b.

The check valve device 50 includes a check valve hole 50a, a valve body 50b, and a spring device 50c for urging the valve body. The check valve hole 50a is a cylindrical horizontal hole larger than the diameter of the gas passage C80c, and is opened on the outer peripheral surface of the fixed scroll 15, and the gas passage B80b is opened on the side surface, and the opening end thereof is the valve body 50b or It is set smaller than the outer dimensions of the spring device 50c.

The valve body 50b has a dimensional configuration that allows the valve body 50b to move up to the stepped portion of the connection portion between the gas passage C80c and the check valve hole 50a.

The partition liner 79 is shrink-fitted and fixed to the small-diameter outer peripheral portion on the lower side of the stepped outer peripheral portion of the fixed scroll 15, seals the shrink-fitted surface, and closes the opening end of the check valve hole 50a.

Further, the outer peripheral surface of the partition liner 79 and the projecting ridges 79a provided on the entire circumference of the outer peripheral surface of the partition liner 79 are in contact with the inner wall surfaces of the upper closed case 1a and the lower closed case 1b.
79a, the upper closed case 1a and the lower closed case 1b are hermetically welded by a single welding bead 79b.

Accumulator chamber leading to the evaporator side of the refrigeration cycle 46
Is formed of the lower closed case 1b and the fixed scroll member 15e, and a heat insulating cover 82 made of resin is attached to the inside of the lower closed case 1b.

The resin baffle 83 is sandwiched between the fixed scroll member 15e and the heat insulating cover 82 to partition the accumulator chamber 46 into a lower gas-liquid separation chamber 84 and an upper suction passage 85.

The suction pipe 47, which penetrates through the side walls of the lower closed case 1b and the heat insulating cover 82 and is provided below the baffle 83, has its terminal end opened to face the baffle 83, and the gas-liquid separation chamber 84 and the suction passage.
Inhalation guide hole 86 provided in baffle 83 communicating with 85
It is provided at a position away from.

Further, a small-diameter oil hole 87 is provided in the middle of the suction pipe 47, and the refrigerant liquid and the lubricating oil staying at the bottom of the gas-liquid separation chamber 84 reflow into the suction pipe 47 little by little.

The two vertical suction holes 43 provided in the fixed scroll 15 connect the suction chamber 17 and the suction passage 85.

Thrust bearing 20 that can be moved only in the axial direction by being constrained by split pin-shaped parallel pins 19 fixed to the body frame 5.
And the end plate 15b of the fixed scroll 15 between the spacer 2
1 is provided, and the axial dimension of the spacer 21 is set to be about 0.015 to 0.020 mm larger than the thickness of the lap supporting disk 18c in order to improve the sealing property of the sliding surface by the oil film.

The eccentric bearing space 36 between the bottom of the eccentric bearing 14 of the drive shaft 4 and the shaft of the orbiting shaft 18b of the orbiting scroll 18, and the outer peripheral space 37 of the lap supporting disk 18c are the orbiting shaft 18b and the wrap supporting. The oil holes A38a provided in the disk 18c communicate with each other.

The thrust bearing 20 is made of a sintered alloy, and is shown in FIGS.
As shown in the figure, the central part has two parallel straight line parts 22,
A precision hole having a shape consisting of two arcuate curved portions 23 connected to it is formed by penetration.

The rotation preventing member (hereinafter referred to as Oldham ring) 24 of the orbiting scroll 18 is made of a light alloy or a reinforced fiber composite resin material suitable for sintering molding, injection molding, etc., and also has oil impregnation characteristics. As shown in FIG. 4, FIG. 5, and FIG. 6, it is composed of a thin annular plate 24a whose both surfaces are parallel to each other, and a pair of parallel key portions 24b provided on one surface of the annular plate 24a. A straight line portion 25 and two arcuate curved line portions 26 connected to the straight line portion 25. The straight line portion 25 engages with the straight line portion 22 of the thrust bearing 20 with a minute gap as shown in FIGS. Yes, the side surfaces 24c of the parallel key portion 24b are orthogonal to each other in the central portion of the straight line portion 25, and as shown in FIG. 2, a pair of key grooves 71 provided in the lap support disk 18c of the orbiting scroll 18 are provided.
It is engaged with a small clearance and has a slidable shape. The inner contour of the annular plate 24a has a shape similar to the outer contour. Further, the recessed portion 24d provided at the base of the parallel key portion 24b also serves as a passage for the lubricating oil. Further, the dent portion 24e provided in the arc-shaped curved portion is a similar lubricating oil passage.

As shown in FIG. 1 and FIG. 3, a release gap 27 of about 0.1 mm is provided between the body frame 5 and the thrust bearing 20. The release gap 27 faces the release gap 27, and the body frame 5 also has an annular groove. A rubber seal ring 70, which is provided with 28 and surrounds the annular groove 28, is mounted between the body frame 5 and the thrust bearing 20.

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

The discharge pipe 31 and the glass terminal 88 side and the motor 3 side are partitioned by a thin oil separator 89 attached to the upper closed case 1a, and a punched hole 90 is provided in the center of the oil separator 89. ing.

The discharge chamber oil sump 34 provided in the lower portion of the motor chamber 6 communicates with the upper portion of the motor chamber 6 and a cooling passage 35 provided by cutting a part of the outer periphery of the stator 3b of the motor 3. The discharge chamber oil sump 34 communicates with the annular groove 28 through an oil hole D38d provided in the main body frame 5, and the back pressure chamber 39 of the orbiting scroll 18 in which the Oldham ring 24 is arranged through an oil hole B38b.
In addition, through the minute gap in the sliding portion of the lower bearing 11 and the oil groove (not shown) in the main bearing 12 to the eccentric bearing space 36 through the oil groove A40a provided in the eccentric bearing 14. Is also in communication.

The oil hole B38b provided in the main body frame 5 also communicates with a spiral oil groove 41 provided on the surface of the lower shaft portion 4a corresponding to the upper bearing 11 of the drive shaft 4, and the spiral oil groove 41 The winding direction is provided so as to generate a screw pump action utilizing the viscosity of the lubricating oil when the drive shaft 4 rotates in the forward direction, and the end thereof is formed part way up to the middle of the upper bearing 4a.

The rotational imbalance caused by the eccentric weight and eccentricity of the lower end of the drive shaft 4 and the weight of the orbiting scroll 18 causes the balance weight 7 attached to the upper and lower ends of the rotor 3a.
Solved by 5,76.

The second compression chamber 51 that does not communicate with the suction chamber 17 or the discharge port 16
The outer space 37 and the outer peripheral space 37 are communicated with each other through an injection passage 55 which is opened in the second compression chamber 51 and is formed of a small diameter injection hole 52 and an oil hole C38c provided in the lap support disk 18c of the orbiting scroll 18. In the oil hole C38c, as shown in FIGS. 8 to 10, the oil supply passage is switched according to the orbiting speed of the orbiting scroll 18, and the oil passage control valve device 91 having a check valve function is mounted. Has been done.

The check valve device 91 urges the valve body 93 mounted in the stepped small diameter cylindrical hole 92 of the oil hole C38c, the plunger 94 and the plunger 94 mounted in the large diameter cylindrical hole 92a of the oil hole C38c. A coil spring 95 and a set screw 97 which stops the movement of the coil spring 95 and is provided with an oil passage 96 in the center thereof are constituted.

The valve body 93 made of a light specific gravity material such as Teflon or ceramics is provided with a vertical groove 93a penetrating the outer periphery thereof, and can smoothly reciprocate in the small diameter cylindrical hole 92. The plunger 94, which is made of a material having a large specific gravity such as brass, has a passage A98a in its central portion, a circumferential groove 98c in its outer peripheral portion, and a passage A98.
A passage B98b is provided that connects a and the circumferential groove 98c.

The coil spring 95 is made of a material having a shape memory characteristic that contracts when the temperature of the coil spring 95 exceeds a preset temperature (for example, 130 ° C.) and expands when the temperature of the coil spring 95 decreases.

The wrap support disk 18c of the orbiting scroll 18 has a suction chamber 17
And a large-diameter cylindrical hole 92 are communicated with each other, and a small-diameter bypass hole 99 is provided, and the bypass hole 99 is opened and closed depending on the stationary position of the plunger 94.

In FIG. 11, 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 in the suction / compression / discharge processes, and the solid line 62 represents the normal pressure during operation. The pressure change is shown, and the dotted line 63 shows the pressure change when the abnormal pressure rises.

In FIG. 12, the horizontal axis indicates the rotation angle of the drive shaft 4, the vertical axis indicates the refrigerant pressure, and the solid line 64 indicates the discharge chamber 2 as well as the suction chamber 17.
The pressure change at the opening positions of the injection holes 52a, 52b of the second compression chambers 51a, 51b which do not communicate with
Indicates the pressure change at the fixed points of the first compression chambers 61a, 61b (see FIG. 7) communicating with the suction chamber 17, and the alternate long and short dash line 66 shows the pressure change at the fixed points of the third compression chambers 60a, 60b communicating with the discharge chamber 2. The two-dot chain line 67 indicates the first compression chambers 61a, 61b and the second compression chambers 61a, 61b.
Shows the pressure change at a fixed point between the compression chambers 51a, 51b,
The double dotted line 68 shows the pressure change in the back pressure chamber 39.

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

In FIG. 1 to FIG. 12, when the drive shaft 4 is rotationally driven by the motor 3, the orbiting scroll 18 tries to rotate around the main shaft of the drive shaft 4 by the crank mechanism of the drive shaft 4, but is parallel to the Oldham ring 24. Since the key portion 24b is engaged with the key groove 71 of the orbiting scroll 18, and the linear portion 25 is engaged with the linear portion of the thrust bearing 20 which is prevented from rotating,
It is prevented from rotating, and revolves to change the volume of the compression chamber together with the fixed scroll 15 so that refrigerant gas is sucked and compressed.

Then, the suction refrigerant of the gas-liquid mixture containing the lubricating oil from the refrigeration cycle connected to the compressor flows from the suction pipe 47 into the accumulator chamber 46, collides with the baffle 83, and the weight difference between the gas and the liquid or the direction change. Is separated into gas and liquid by the inertial force, and the liquid refrigerant accumulates at the bottom of the accumulator chamber 46.

The heat quantity of the motor chamber 6 transmitted to the lower closed case 1b through the closed case 1a is shielded by the heat insulating cover 82 and the baffle 83 having heat insulating properties, and the heat transfer to the suction refrigerant is small.

In addition, the collision sound and vibration generated when the refrigerant flows into the accumulator chamber 46 and collides with the inner wall or the like is blocked and absorbed by the heat insulating cover 82.

The separated intake gas is introduced into the intake guide hole 86, the intake passage 42,
The orbiting scroll enters the suction chamber 17 through the suction holes 43 in sequence.
First compression chamber 61 formed between 18 and fixed scroll 15
After being sealed in the compression chamber via a and 61b, transferred and compressed sequentially to the second compression chambers 51a and 51b and the third compression chambers 60a and 60b, which are always closed spaces, and compressed from the discharge port 16 in the central portion to the check valve device 50. Is discharged to the motor chamber 6 through the discharge passage 80 against the urging force of.

The discharge refrigerant gas discharged obliquely inward from the tip of the discharge gas guide 81 collides with the rotor 3a of the motor 3 and the balance weight 75 to be diffused, and the lower coil end of the motor 3 is discharged.
After passing between the windings of 30a, it flows into the upper space of the motor chamber 6 while cooling the motor 3 through the cooling passage 35 in the outer peripheral portion of the stator 3b, and after being converted into an inward flow again, the central portion After passing through the inner hole 90, the discharge pipe 31 at the outer peripheral portion is sent to the external refrigeration cycle.

At this time, a part of the lubricating oil in the discharged refrigerant gas adheres to the surfaces of the many windings of the motor coil end, is separated from the refrigerant gas, and is collected in the discharge chamber oil sump 34.

The lubricating oil in the discharge chamber oil sump 34 passes through the process described below, and the back pressure chamber 39
The pressure in the back pressure chamber gradually increases. Due to the back pressure, the lap support disk 18c of the orbiting scroll 18 urges and contacts the end plate 15d of the fixed scroll 15, the axial gap of the compression chamber disappears, the compression chamber is sealed, and the suction refrigerant gas is efficiently compressed and stabilized. Operation continues.

The pressure in the compressor is balanced, the liquid refrigerant exists not only in the accumulator chamber 46 but also in the compression chamber, and when the compressor is cold-started from the state where liquid compression is likely to occur, the pressure of the compressed refrigerant in the compression chamber Orbiting scroll 18 on discharge port
Thrust force in the direction opposite to 16 acts. However, since the back pressure necessary for biasing is not generated on the back surface of the orbiting scroll 18, the orbiting scroll 18 is separated from the fixed scroll 15 and is supported by the thrust bearing 20. At this time, a gap of about 0.015 to 0.020 mm is generated in the axial direction of the compression chamber. as a result,
The pressure in the compression chamber drops temporarily, reducing the compression load in the initial stage of startup.

The initial supporting force of the thrust bearing 20 for supporting the orbiting scroll 18 depends on the elastic force of the seal ring 70 and an auxiliary spring device (for example, US Pat. No. 3,600,114) as described later.

If liquid compression occurs in the compression chamber and the pressure in the compression chamber rises abnormally momentarily, the thrust force acting on the orbiting scroll 18 becomes larger than the biasing force acting on the back surface of the orbiting scroll 18, The scroll 18 moves in the axial direction, the lap support disc 18c of the orbiting scroll 18 is separated from the end plate 15b of the fixed scroll 15 and supported by the thrust bearing 20, and the compression chamber is unsealed, so that the pressure in the compression chamber increases. It lowers and the compression load is reduced.

The lubricating oil in the oil reservoir 34 of the discharge chamber is sucked in from the oil hole B38b, and is supplied to the thrust ball bearing 13 by the screw pump action of the spiral oil groove 41 provided on the surface of the upper shaft portion 4a of the drive shaft 4. When the lubricating oil passes through the minute bearing gap at the end of the portion 4a, the discharge refrigerant gas atmosphere of the motor chamber 6 and the upstream side space of the upper bearing 10 are shut off by the sealing action of the oil film.

The lubricating oil containing the dissolved discharge refrigerant gas of the discharge chamber oil sump 34 is reduced to an intermediate pressure between the discharge pressure and the suction pressure when passing through the minute gap of the lower bearing 11, and flows into the back pressure chamber 39. After that, the oil flows through the oil groove A40a of the eccentric bearing 14, the eccentric bearing space 36, and the oil hole A38 passing through the orbiting scroll 18 into the outer peripheral space 37 while being gradually reduced in pressure.

On the other hand, when the rotational speed of the drive shaft 4 is equal to or lower than the set rotational speed (for example, 6000 rpm), the centrifugal force generated by the orbiting scroll 18 and generated in the plunger 94 is smaller than the biasing force of the coil spring 95. , The end surface of the plunger 94 comes into contact with the bottom surface of the large-diameter cylindrical hole 92a as shown in FIG.
The cylindrical groove 98c leading to the passage A98a does not pass through the bypass hole 99 of the lap support disk 18c, but through the stepped small diameter cylindrical hole 92, the vertical groove 93a provided in the valve body 93, and the small diameter injection holes 52a, 52b. Second compression chamber that does not communicate with discharge port 16 or suction chamber 17
It communicates with 51a and 51b.

Therefore, the lubricating oil in the outer peripheral space 37 is the oil passage 96 and the oil hole C3.
8c, injection holes 52a, 52b and then second compression chambers 51a, 5
It flows into 1b and lubricates each sliding surface in the passage.

The lubricating oil injected into the second compression chambers 51a and 51b merges with the lubricating oil that has flowed into the compression chambers together with the suction refrigerant gas, and seals a minute gap between adjacent compression chambers with an oil film to prevent leakage of the compressed refrigerant gas. , The motor chamber 6 through the discharge port 16 together with the compressed refrigerant gas while lubricating the sliding surface between the compression chambers.
Is discharged again.

Further, since the discharge chamber oil sump 34 also communicates with the annular groove 28 and the release gap 27, the thrust bearing 20 is biased by the back pressure thereof and abuts against the end surface of the spacer 21. The wrap support disk 18c of the orbiting scroll 18 smoothly slides while maintaining a small gap between the thrust bearing 20 and the end plate 15b of the fixed scroll 15, and the fixed scroll wrap 15a.
The gap between the end face of the wrap support disc 18c and the end face of the orbiting scroll wrap 18a and the end plate 15b is kept small, and gas leakage between the adjacent compression chambers is reduced.

The openings of the injection holes 52a, 52b of the second compression chambers 51a, 51b change in pressure as shown in FIG. 12, and are instantaneously higher than the back pressure chamber pressure 68 which changes following the pressure of the motor chamber 6. But the average pressure is low. Therefore, the lubricating oil from the back pressure chamber 39 intermittently flows into the second compression chambers 51a and 51b, and the second compression chambers 51a and 51b are instantaneously higher than the back pressure chamber pressure 68 during normal operation.
The compressed refrigerant gas inside has small diameter injection holes 52a, 52
There is little instantaneous backflow to the oil hole C38c due to decompression at b, and the pressure in the oil hole C38c does not become higher than the back pressure chamber pressure 68.

In addition, as mentioned above, the seal ring
The orbiting scroll 18 is supported via the thrust bearing 20 by the elastic force of 70 and the spring device, but the lubricating oil differentially supplied to the back pressure chamber 39 after the compressor has been stabilized stabilizes the urging force of the intermediate pressure. By acting on 18, the lap support disk 18c seals the sliding surface with the end plate 15b with a pressing oil film, and cuts off the communication between the outer peripheral space 37 and the suction chamber 17. Further, the lubricating oil in the back pressure chamber 39 is present in the gap between the sliding surfaces of the thrust bearing 20 and the lap support disk 18c, and seals the gap (about 0.015 to 0.020 mm).

In addition, for a while after the cold start of the compressor,
As can be understood from FIG. 12, the pressure in the motor chamber 6 is lower than the pressure in the second compression chambers 51a, 51b, and the refrigerant gas in the middle of compression passes from the second compression chambers 51a, 51b through the oil supply passage control valve device 91 and moves back. Although it tries to flow back into the pressure chamber 39, as shown in FIG.
The non-return action of prevents the backflow to the outer peripheral space 37,
The lubricating oil in the discharge chamber oil sump 34 is differentially supplied to the back pressure chamber 39 and the outer peripheral space 37 as the pressure in the motor chamber 6 rises.

That is, the lubricating oil pressure in the outer peripheral space 37 is low for a while after the cold start of the compressor. Therefore, the refrigerant gas in the middle of compression flows backward from the injection holes 52a, 52b to the stepped small-diameter cylindrical hole 92, and resists the biasing force of the coil spring 95, so that the valve body 93
Moves toward the outer peripheral space 37 while closing the end surface of the plunger 94, contracts the coil spring 95 to a substantially intimate contact state and stops, and the cylindrical groove 98c and the small-diameter bypass hole 99 communicate with each other. As a result, the backflow of the compressed refrigerant gas from the second compression chambers 51a, 51b to the outer peripheral space 37 is blocked, and the outer peripheral space 37 and the suction chamber 17 communicate with each other. As a result, the lubricating oil in the discharge chamber oil sump 34 sequentially flows into the suction chamber 17 through the back pressure chamber 39 and the outer peripheral space 37, and lubricates the sliding portion during refueling.

After that, as the pressure in the motor chamber 6 rises, the lubricating oil in the outer peripheral space 21 rises in pressure, and the valve body 93 moves to the position shown in FIG. 9 due to the pressure difference with the stepped small diameter cylindrical hole 92, and the injection hole 52
a, 52b is injected into the second compression chambers 51a, 51b,
Cut off the passage to the suction chamber 17.

In addition, when the pressure of the suction refrigerant gas is very high as immediately after cold start and the compression ratio of the scroll compressor is constant, the compression chamber pressure also becomes very high, or abnormal liquid compression occurs. In such a case, the orbiting scroll 18 separates from the fixed scroll 15 and the thrust bearing 20
Supported by. However, the thrust bearing 20 biased by the back pressure cannot support the thrust load acting on the orbiting scroll 18 due to the abnormally increased compression chamber pressure,
The axial clearance between the orbiting scroll 18 and the fixed scroll 15 is expanded by retracting in the direction of decreasing the release clearance 27. As a result, a large amount of leakage occurs in the compression space, the pressure in the compression chamber suddenly drops, and the compression load is instantly reduced, then the thrust bearing 20 instantly returns to its original position, and the pressure in the back pressure chamber 39 is reduced. Stable operation will continue without any significant decrease.

Also, when foreign matter is caught in the axial gap between the orbiting scroll 18 and the fixed scroll 15, the thrust bearing 20 retreats and removes the foreign matter in the same manner as described above.

In addition, the pressure in the compression chamber when instantaneous liquid compression occurs at the initial stage of cold start or during steady operation causes abnormal pressure rise and overcompression as shown by the dotted line 63 in FIG. Since the volume of the high pressure space communicating with each other is large, the increase in the pressure of the motor chamber 6 is extremely small.

Also, due to the liquid compression, the stepped small-diameter cylindrical hole 92 and the like communicating with the second compression chambers 51a and 51b also have an abnormal pressure rise, but due to the check action of the check valve 93, the outer peripheral space 37 and the stepped small-diameter cylindrical hole 92. Is cut off between and. As a result, the pressure in the back pressure chamber 39 does not change, and the back pressure urging force acting on the back surface of the thrust bearing 20 does not change. As a result, during liquid compression, the orbiting scroll
Due to the excessive thrust force acting on 18, the thrust bearing 20 retracts as described above, the pressure in the compression chamber drops, and normal operation is continued.

Incidentally, the thrust bearing 20 retracts during the decompression, so that the pressure in the compression chamber is reduced in the middle as indicated by the alternate long and short dash line 63a in FIG.

Further, the differential pressure decreases as the gas leakage in the compression chamber per unit time decreases, the amount of oil injection into the compression chamber is suppressed, and the pressure in the back pressure chamber 39 gradually increases during high-speed operation of the compressor (for example, , The rotation speed of the motor 3 is 8000 rpm), the check valve is generated when the orbiting scroll 18 orbits.
The resultant centrifugal force generated by 93 and the plunger 94 becomes larger than the urging force of the coil spring 95, and the check valve 93 and the plunger 94 move against the urging force of the coil spring 95, causing the liquid compression. As in the case, stop at the position shown in FIG.

Therefore, the outer peripheral space 37 and the second compression chambers 51a and 51b are disconnected from each other, and the outer peripheral space 37 and the suction chamber 17 communicate with each other. Then, the lubricating oil in the outer peripheral space 37 does not flow into the second compression chambers 51a and 51b, but is decompressed when passing through the bypass hole 99 and is sucked into the suction chamber.
Inflow to 17. The inflow of lubricating oil into the suction chamber 17 reduces the pressure of the back pressure chamber 39 communicating with the outer peripheral space 37 to an appropriate back pressure, and the biasing force of the orbiting scroll 18 to the fixed scroll 15 is appropriately maintained. The lubricating oil flowing into the suction chamber 17 is sucked into the compression chamber together with the suction refrigerant gas, and then discharged to the motor chamber 6.

Further, when the pressure in the back pressure chamber 39 rises abnormally, the coil spring 95 is generated due to the frictional heat of the sliding surface between the lap support disk 18c of the orbiting scroll 18 and the end plate 15b of the fixed scroll 15.
Exceeds the set temperature and weakens the urging force to the plunger 94. As a result, the plunger 94 moves toward the coil spring 95 and stops at the position shown in FIG. 10 as in the high speed operation of the compressor. Then, similarly to the above, the suction chamber 17 and the outer peripheral space 37 communicate with each other, the pressure in the back pressure chamber 39 decreases, and the back pressure chamber 39 is properly held.

After the compressor is stopped, the orbiting scroll is performed due to the pressure in the compression chamber.
Reverse orbiting torque is generated in 18, and the orbiting scroll 18 is orbited in the reverse direction, and the discharged refrigerant gas flows back to the suction side. Following this reverse flow of the discharged refrigerant gas, the check valve device 50 moves from the position shown in FIG. 1 to the discharge port 16 side and seals the bottom surface of the check valve hole 50a to prevent the reverse flow of the discharged refrigerant gas. Then, the reverse orbit of the orbiting scroll 18 is stopped, and the space between the suction passage 42 and the gas passage C80c holds the suction side pressure.

Also, when the pressure in the motor chamber 6 drops to some extent,
The lubricating oil in the discharge chamber oil sump 34 stops the differential pressure oil supply to the outer peripheral space 37 due to the passage resistance of the oil supply passage.

Further, during operation of the compressor, the oil supply upstream side of the upper bearing 11 communicates with the discharge chamber oil sump 34, and the oil supply downstream side is a back pressure chamber in an intermediate pressure state
39, a differential pressure is generated between them, and the rotor 3a of the motor 3
The drive shaft 4 fixed to is orientated toward the orbiting scroll 18. This urging force is supported by the main body frame 5 via the thrust ball bearing 13, and the drive shaft 4 is supported by the upper bearing 10 and the main bearing 12.
Within the range of the gap between the upper bearing and the upper bearing, the falling of the drive shaft 4 due to imbalance or compression load is prevented.
Prevent uneven contact between 10 and main bearing 12.

Further, due to the temperature rise during the operation of the compressor, the main body frame 5 made of aluminum alloy thermally expands to expand the iron liner 8, and the outer peripheral surface of the liner 8 and the inner wall of the closed case 1 are intimately adhered to each other. Helps to improve rigidity.

Further, in the above-described embodiment, the lubricating oil in the discharge chamber oil sump 34 is oil-injected into the second compression chambers 51a, 51b, but it is injected into the first compression chambers 61a, 61b leading to the suction chamber 17 depending on the compressor operating conditions. May be.

Further, in the above embodiment, the lubricating oil of the discharge chamber oil sump 34 is introduced into the release gap 27 and the annular groove 28 provided on the back surface of the thrust bearing 20, but the discharge refrigerant gas of the motor chamber 6 and the second compression chambers 51a, 51a.
Intermediate pressure refrigerant gas may be introduced from b or the like.

Further, although the check valve device 50 is provided in the discharge passage 80 in the above embodiment, depending on the internal volume of the closed case 1 and the amount of lubricating oil, the check valve device 50 operates vertically between the suction chamber 17 and the suction hole 43. A free valve type check valve may be provided.

Further, although the suction passage 85 is provided between the suction hole 43 and the suction guide hole 86 in the above embodiment, the suction hole 43 and the suction guide 86 may be directly communicated with each other.

Further, FIGS. 13 and 14 show different embodiments of the accumulator chamber, and the accumulator chamber 46a shown in FIG. 13 is a partition wall provided on the inner wall of a resin heat insulating cover 82a having excellent heat insulating characteristics. The gas-liquid separation chamber 84a is divided into a liquid storage chamber 84a1 and a suction chamber 84a2 by 82b, and the upper end of the partition wall 82b extends to a position higher than the lower end of the suction guide hole 86a provided in the baffle 83a. is there. Therefore, the liquid refrigerant flowing from the suction pipe 47 does not evaporate and does not flow into the suction guide hole 86a through the short circuit path.

The accumulator chamber 46b shown in FIG. 14 has a structure in which the suction chamber 84a2 of FIG. 13 is divided into two chambers by a partition wall 83b1 extending downward from the baffle 83b.
This configuration is suitable for a compressor in a refrigeration cycle operated under the condition that the suction refrigerant passage is long, the temperature of the gas-liquid mixed refrigerant flowing into the accumulator chamber 46b is low, and the refrigerant evaporation in the accumulator chamber 46b is small.

As described above, according to the above-described embodiment, the fixed scroll member 15e including the fixed scroll 15 and the partition liner 79 fixed by shrink fitting to the fixed scroll member 15e is engaged with the orbiting scroll 18 performing the orbiting motion, and the orbiting scroll 18 is provided. A scroll compression supporting the drive shaft 4 for driving the orbiting scroll 18 and engaging the Oldham ring 24, which is a rotation preventing member of the orbiting scroll 18, with the main body frame 5 to which the fixed scroll member 15e is fixed by bolts. The mechanism is housed in the closed case 1, and the inside of the closed case 1 is a fixed scroll member 15.
By e, the motor chamber 6 on the high pressure side and the accumulator chamber 46 for separating and accumulating the suction refrigerant are separated from each other, the accumulator chamber 46 on the low pressure side is arranged in the lower part, and the motor chamber 6 is arranged in the upper part. Is a fixed scroll member 15e that forms the accumulator chamber 46 and the inner wall of the lower hermetically sealed case 1b, which is provided with a heat insulating and soundproofing effect. Since it is covered with the resin heat insulating cover 82 and the baffle 83, the compressed refrigerant gas, the heat generated in the sliding portion, the motor 3
Due to the amount of heat transferred from the upper closed case 1a that is heated by the heat generated by the heat transfer from the lower closed case 1b, the heat transfer from the motor chamber 6 and the fixed scroll member 15e heated by the heat of the compression chamber , Insulation cover 82
The baffle 83 and the baffle 83 can cut off the heating, reduce the heating of the suction refrigerant gas and the suction refrigerant liquid, and prevent the compression efficiency from decreasing. As a result, the accumulator chamber 46, which has a gas-liquid separation and storage function for the suction refrigerant, can be built in the closed case 1, and the external dimensions of the compressor can be reduced.

Further, like the conventional mounting structure of the accumulator, resonance of the accumulator due to vibration of the compressor, further, vibration of the pipe connected to the compressor does not occur,
It is also possible to reduce the vibration and noise of the devices that make up the refrigeration cycle.

Further, since the heat insulating cover 82 and the baffle 83 are made of a soft material and have a low natural frequency characteristic and have a soundproof function, the suction refrigerant flows into the accumulator chamber 46, and a collision sound with the inner wall thereof and a gas-liquid separation. The expansion sound generated at the time of does not propagate to the outside of the compressor, and particularly, since the scroll compressor is originally quiet, the soundproofing function is effective, and an extremely quiet scroll refrigerant compressor can be realized.

Further, since the accumulator chamber 46 is at the bottom of the compressor, the side close to the high-temperature motor chamber 6 becomes the gas space side of the suction refrigerant, and the refrigerant in the gas state of low density has low thermal conductivity, so that heating to the suction refrigerant is performed. Can be further reduced.

Further, according to the above-described embodiment, the accumulator chamber 46 having the gas-liquid separation and storage function has the suction passage 85 from which the suction refrigerant gas is sucked into the compression chamber,
Even if the accumulator chamber 46 is filled with the liquid refrigerant while the compressor is stopped, no liquid refrigerant flows into the compression chamber,
It is possible to reduce decompression at the time of starting the compressor, reduce vibration and abnormal noise of the compressor, and improve durability.

Further, according to the above embodiment, the accumulator chamber 46 (46
a, 46b) inside the heat insulation cover 82a, (82c), baffle 83a (8
3b) is provided with a partition wall 82b (82d), 83b1 that protrudes toward the inner wall side, and a suction chamber 46a1 (46b1) for bypassing the suction refrigerant gas separated from the gas-liquid separation chamber is provided. With a simple structure, it is possible to prevent the gas-liquid mixed refrigerant flowing from the suction pipe 47 from flowing into the compression chamber through the short-circuit route, vaporize the refrigerant in the middle of the suction refrigerant passage, and reduce the compression load. Can be done.

Further, by providing an overload reducing mechanism of a type that widens the axial clearance of the compression chamber as in the above embodiment, it is possible to perform a liquid compression operation to some extent, so that the volume of the accumulator chamber 46 is made small and gas-liquid separation is performed. It is also possible to reduce efficiency.
As a result, the heat transfer area from the motor chamber 6 or the like can be reduced, so that the heat absorption of the sucked refrigerant can be reduced to improve the compression efficiency, and a small scroll refrigerant compressor can be realized.

In addition, although the operation of the refrigerant compressor has been described in the above-described embodiment, the same operational effect can be expected in the case of other gas compressors such as oxygen, nitrogen, and helium that use lubricating oil.

As described above, the present invention stores the scroll compression mechanism in a closed container, and divides the closed container into a high pressure chamber and a low pressure chamber for separating and accumulating gas and liquid of an intake fluid by a fixed scroll member, The low-pressure chamber is located in the lower part, the high-pressure chamber is located in the upper part, and the drive device related to the scroll compression mechanism is located in the high-pressure chamber.
By covering most of the inner wall of the member forming the low-pressure chamber with a low natural frequency member made of a low specific gravity and soft material that has both heat insulation and soundproofing properties, compressed gas, sliding part heat generation, drive device heat generation, etc. The heat transferred from the heated upper part of the closed case causes the temperature to rise to the lower part of the closed case, the heat transfer from the high pressure chamber, and the heat transferred from the fixed scroll member heated by the heat of the compression chamber to form the low pressure chamber. It can be shut off by a member, the heating of the suction fluid can be reduced, and the reduction of compression efficiency can be prevented. As a result, it is possible to incorporate a low-pressure chamber having a gas-liquid separation and storage function for the suction fluid in a closed container in terms of performance, and reduce the external dimensions of the compressor.

Also, since the low-pressure chamber is integrated with the closed container, resonance of the accumulator due to vibration of the compressor, as in the conventional separate installation of an accumulator with gas-liquid separation and storage functions, and further connection to the compressor There is little pipe vibration,
It is also possible to reduce the vibration and noise of the mechanical device using the compressor.

Further, the inner wall of the member forming the low pressure chamber has a low specific gravity and a low natural frequency characteristic made of a soft material, and has a soundproof function, so that the suction fluid flows into the low pressure chamber and the collision noise with the inner wall is generated. Also, the expansion noise generated during gas-liquid separation does not propagate to the outside of the compressor, and it is possible to reduce the thickness by reducing the thickness of the closed container in the low pressure chamber. In particular, scroll gas compressors originally have
Since it is quiet, the soundproofing function is effective, and it is possible to realize an extremely quiet scroll gas compressor.

In addition, since the low-pressure chamber is at the bottom of the compressor, the side close to the high-temperature high-pressure chamber becomes the gas space side of the suction fluid, and the gas with low density has low thermal conductivity, so the suction fluid is not heated and the compression efficiency is high. As a result of preventing the decrease, it is possible to achieve the effects of miniaturization, high efficiency maintenance, and quietness of the low-pressure chamber built-in type compressor having a gas-liquid separation and storage function of the intake fluid.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a scroll refrigerant compressor according to an embodiment of the present invention, FIG. 2 is an exploded view of main parts of the compressor, and FIG. 3 is a partial detailed view of a thrust bearing portion of the compressor. 4 is an external view of an Oldham ring in the compressor, FIG. 5 is an external view of the Oldham mechanism assembly in the compressor, FIG. 6 is an upper plan view in FIG. 5, and FIG.
8 and 10 are detailed views of the mounting portion of the oil supply passage control valve device in FIG. 1, and FIG. 9 is the oil supply in FIGS. 8 and 10. Fig. 11 is an external view of the parts constituting the passage control valve device, Fig. 11 is a characteristic diagram showing the pressure change of the refrigerant gas from the intake stroke to the discharge stroke of the compressor, and Fig. 12 shows the pressure change at a fixed point in each compression chamber. FIG. 13 is a longitudinal sectional view of the accumulator chamber portion of the scroll refrigerant compressor according to the second and third embodiments of the present invention, and FIG. 15 shows a general refrigeration cycle. FIG. 16 is a vertical cross-sectional view of an accumulator connected to the compressor shown in FIG. 15, and FIG. 17 is a vertical cross-sectional view of a scroll gas compressor incorporating a conventional accumulator. 2 ... Discharge chamber, 3 ... Motor, 4 ... Drive shaft, 5 ... Main frame, 6 ... Motor chamber, 15 ... Fixed scroll,
15a: fixed scroll wrap, 15b: end plate, 16: discharge port, 17: suction chamber, 18: orbiting scroll, 18a
…… Orbiting scroll wrap, 18c …… Wrap support disc, 2
0 …… Thrust bearing, 27 …… Release gap, 28 …… Annular groove, 34 …… Discharge chamber oil sump, 39 …… Back pressure chamber, 43 …… Suction hole,
46 ... Accumulator chamber, 47 ... Suction pipe, 82 ... Heat insulating cover, 83 ... Baffle, 85 ... Suction passage, 91 ... Oil supply passage control valve device.

Front Page Continuation (72) Inventor Shuichi Yamamoto 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. An orbiting scroll wrap on a lap support disk which is a part of an orbiting scroll is oscillated and rotated with respect to a spiral fixed scroll wrap which is formed on one surface of an end plate which is a part of a fixed scroll member. Engage freely, forming a spiral compression space between both 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. The compression space is divided into a plurality of compression chambers that continuously move from the suction side toward the discharge side to compress the fluid, and a rotation prevention member for the orbiting scroll is provided between the orbiting scroll and the stationary member. To form a scroll compression mechanism that causes the orbiting scroll to orbit, and the scroll compression mechanism is housed in a closed container. Is partitioned by the fixed scroll member into a high pressure chamber and a low pressure chamber for separating and accumulating gas-liquid of the inhaled fluid, the low pressure chamber is arranged in the lower part, and the high pressure chamber is arranged in the upper part, and the high pressure chamber includes the scroll compression chamber. A scroll gas compressor in which a drive device relating to the mechanism is arranged and most of the inner wall of the member forming the low pressure chamber is covered with a low natural frequency member made of a low specific gravity and soft material having both heat insulation and soundproofing properties. 2. The scroll gas compressor according to claim 1, wherein the low-pressure chamber has a suction passage through which air is sucked into the compression chamber from above. 3. The scroll gas compressor according to claim 2, wherein the member for covering the inner wall of the low pressure chamber divides the low pressure chamber into a gas-liquid separation space or storage space for the intake fluid and a passage for the intake gas.