JP2003278672A - Scroll compressor for helium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scroll compressor for helium of such a type that oil injection is made into the compressor, in which the vibration level of an injection piping is reduced and the performance is enhanced. <P>SOLUTION: The scroll compressor for helium is structured so that the dimensionless value (do-t)/t is set in the range according to the following formula: 0.7≤(do-t)/t≤1.5 where do is the hole diameter of a single oil injection port, and t is the scroll lap thickness. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor used for a helium compressor for a cryopump device in an ultra-high vacuum field using helium gas as a working gas, and more particularly to a hermetic scroll compressor.

[0002]

2. Description of the Related Art A conventional scroll compressor for helium, in which helium gas is used as a working gas, employs a so-called high-pressure chamber system in which the closed container is kept at a high pressure and is cooled by oil, a so-called oil injection system. Examples of the oil-injection method are disclosed in Japanese Patent Publication No. 6-17676.
There is a configuration in which the oil in the bottom of the closed container is once guided out of the container and then reinjected into the compressor section of the scroll compressor via an oil cooler.

[0003]

SUMMARY OF THE INVENTION The above-mentioned prior art has the following problems. That is, in the case of the helium compressor, since the helium gas does not dissolve in the oil unlike the refrigerant CFC22 (R22), the oil is not diluted with the refrigerant. Therefore, the natural consequence is that the oil viscosity increases. There is also a problem that particulate gas is mixed into the oil at the bottom of the chamber.

In this case, when an oil injection structure using a differential pressure is adopted and a large amount of oil is to be injected, helium gas will be mixed with the oil in the injection pipe. In that case, the helium gas will enter the pipe. The gas is likely to accumulate and hinders the oil flow, which makes the flow of the injection oil non-uniform, which causes an impact force on the pipe to increase pipe vibration. In addition, the mixed flow of gas and oil causes a problem that compressor noise is increased.

In the above scroll compressor employing the oil injection structure, the gas pressure in the compression on the downstream side of the oil injection pipe fluctuates due to the volume reduction of the compression chamber accompanying the orbiting motion of the orbiting scroll. The pressure difference from the upstream discharge pressure will also fluctuate. Therefore, the oil in the oil injection pipe exhibits a pulsating flow due to the influence of the pressure difference fluctuation.

On the other hand, in the hermetic scroll compressor, the helium gas in the form of fine particles is mixed in the oil in the oil sump at the bottom of the compressor, so that the mixed helium gas is sent to the oil injection pipe. , Will be injected and injected into the compression chamber for cooling.

When the amount of helium gas mixed in the injection oil injected as described above increases, the pulsating flow width of the cooling oil in the injection pipe increases,
Along with this, an intermittent impact force is applied to the oil injection pipe, and as a result, vibration of the oil injection pipe is accelerated, and at the same time, noise is increased, which is a problem inherent to the helium compressor.

An object of the present invention is to solve the above-mentioned various problems in the prior art relating to a hermetic scroll compressor for helium, and to achieve a great reduction in vibration and noise as compared with the conventional compressor. An object of the present invention is to provide an oil-filled hermetic scroll compressor that improves the reliability of the machine and the product quality.

[0009]

In order to achieve the above object, the scroll compressor for helium according to the present invention is characterized by what is stated in each of claims 1 to 4, but as an independent claim. According to the first aspect of the present invention, the scroll compressor for helium is configured such that the fixed scroll and the orbiting scroll in which the spiral wrap is upright on the disk-shaped end plate are engaged with each other with the wrap inside each other, and the orbiting scroll is connected to the rotary shaft. Engages an eccentric mechanism that is installed to cause the orbiting scroll to orbit with respect to the fixed scroll without rotating, and the fixed scroll is provided with a discharge port that opens at the center and an intake port that opens at the outer periphery. The working gas is sucked in, the compression chamber formed by both scrolls is moved with the orbiting motion of the orbiting scroll to reduce the volume, and the working gas is compressed. A scroll compressor configured to discharge a compressed working gas from an outlet to a discharge pipe, wherein the working gas is helium gas, and an oil injection pipe for cooling the helium gas is provided in an end plate portion of the fixed scroll. A helium which is connected to an oil injection port, the opening of the oil injection port facing the wrap tooth tip surface of the orbiting scroll, and the oil injection port provided in the lap tooth groove portion. In the scroll compressor, the oil injection port is a single port, and when the hole diameter is do and the scroll wrap thickness is t, the dimensionless value (do-t) / t is given by It is characterized by being set in the range of. 0.7 ≦ (do-t) /t≦1.5

Similarly, in the hermetic scroll compressor for helium according to the second aspect of the present invention as an independent claim, the scroll compressor section and the electric motor section are housed in a hermetic container, and the scroll compressor section is To rotate the orbiting scroll by engaging a fixed scroll and an orbiting scroll that stand upright with a spiral wrap on a disk-shaped end plate with the wraps inside and engaging an eccentric mechanism that connects the orbiting scroll to a rotating shaft. Instead, the fixed scroll is caused to orbit, and the fixed scroll is provided with a discharge port opening in the center and an inlet opening in the outer peripheral part, and the working gas is sucked in through the inlet, and is accompanied by the orbiting motion of the orbiting scroll. The compression chamber formed by both scrolls is moved around to reduce the volume and compress the working gas, and the compressed working gas is discharged from the discharge port into the closed container chamber. Further, in a hermetic scroll compressor configured to discharge to the outside via a discharge pipe, the working gas is helium gas, and an oil injection pipe for cooling the helium gas is passed through the closed container. It is connected to an oil injection port provided on the end plate portion of the fixed scroll, and the opening of the oil injection port is opened so as to face the wrap tooth tip surface of the orbiting scroll, and the oil injection port is wrapped. In the hermetic scroll compressor provided in the tooth space, the hole diameter of the oil injection port is set larger than the wrap thickness t so that the injection effective area is equivalent to the single port according to claim 1. In addition, a plurality of joint means for connecting the plurality of ports and one oil injection pipe are fixed and provided at a substantially central portion of the lap tooth groove portion. It is characterized in that provided through the sealing means to the roll end plate.

Furthermore, a hermetic scroll compressor for helium according to a third aspect of the present invention as an independent claim further houses a scroll compressor section and an electric motor section in a hermetic container, and at the same time, the scroll compressor section. Is a disk-shaped end plate in which a fixed scroll and an orbiting scroll, which stand upright in a spiral wrap, are engaged with each other with the wraps inside, and engage with an eccentric mechanism that connects the orbiting scroll to a rotating shaft to rotate the orbiting scroll. The fixed scroll has a discharge port that opens in the center and a suction port that opens in the outer periphery.The working gas is sucked through the suction port, and the compression chamber is formed by both scrolls. To reduce the volume to compress the working gas, discharge the compressed working gas from the discharge port into the closed chamber, and then discharge it outside the device through the discharge pipe. In the hermetic scroll compressor, the working gas is helium gas, and an oil injection pipe for cooling the helium gas is provided on the end plate portion of the fixed scroll penetrating the hermetic container. A hermetic scroll compression connected to an injection port, the opening of the oil injection port facing the wrap tooth tip surface of the orbiting scroll, and the oil injection port provided in the lap tooth groove portion. In the machine, the oil injection port is provided as a single port in the substantially central portion of the lap tooth groove portion and has a hole diameter do of the port,
When the scroll lap thickness is t, the dimensionless value (do-t) / t is set in the range of the following equation. 0.7 ≦ (do-t) /t≦1.5

Furthermore, a compressor for helium according to a fourth aspect of the present invention according to a fourth aspect of the present invention is the compressor for helium according to any one of the first to third aspects, wherein the oil injection pipe is penetrated through a hermetically sealed container to form the compressor. It is connected to an oil injection port provided on the end plate portion of the fixed scroll, the opening of the oil injection port is opened facing the wrap tooth front surface of the orbiting scroll, and the oil injection port is a wrap tooth. A position which is provided at approximately the center of the groove and in which the opening of the port is always in communication with the compression chamber, and which is intermittently communicated with the suction chamber at the outer periphery of the scroll wrap by the orbiting motion of the orbiting scroll. It is characterized in that it is provided with an oil injection mechanism as described in (1).

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to FIGS. 1 to 8, and prior to that, a general structure of a scroll compressor for helium will be described. Figure 1
Shows a particularly hermetic scroll compressor for helium as an object of the present invention. In the figure, a scroll compressor section 2 is located above a hermetic container 1, and a motor section 3 is located below.
Is stored. The inside of the closed container 1 is the upper chamber 1a.
And a motor room 1b. In the scroll compressor unit 2, a fixed scroll 5 and an orbiting scroll 6 are meshed with each other to form a compression chamber (closed space) 8. The fixed scroll 5 is composed of a disk-shaped end plate 5a and a wrap 5b which stands upright on the end plate 5a and has an involute curve or a curve similar to this, and has a discharge port 10 at the center thereof and a suction port 15a at the outer periphery thereof. 15b is provided. The orbiting scroll 6 is composed of a disk-shaped end plate 6a, a wrap 6b standing upright on the end plate and having the same shape as the wrap of the fixed scroll, and a boss portion 6c formed on the non-lap surface of the end plate. The frame 11 has an auxiliary bearing 26 and a main bearing 2 in the central portion.
7, the rotary shaft 16 is supported by these bearings, and the eccentric shaft 16a at the tip of the rotary shaft is inserted into the boss portion 6c so as to be capable of turning motion.

The fixed scroll 5 is fixed to the frame 11 by a plurality of bolts, and the orbiting scroll 6 is supported by the frame 11 by an Oldham mechanism 12 including an Oldham ring and an Oldham key. , Is formed so as to perform a turning motion without rotating. An electric motor shaft 16b is integrally connected to the lower portion of the rotary shaft 16 to directly connect the electric motor unit 3. At the suction port 15a of the fixed scroll 5, the closed container 1
A vertical suction pipe 17 is connected through the discharge port 1
The upper chamber 1a in which 0 is open communicates with the electric motor chamber 1b via the passages 18a and 18b. This electric motor room 1b
Communicates with a discharge pipe 19 penetrating the closed container 1.

The upper and lower portions of the electric motor chamber 1b are provided with a gap 25 between the electric motor stator 3a and the side wall of the closed casing 1.
(25b, 25c) and the electric motor stator 3a and the electric motor rotor 3b communicate with each other through a gap. 9a
Reference numerals 9b and 9b are a balance weight and a sub-weight for canceling the centrifugal force generated by the orbiting movement of the orbiting scroll 6. Further, an O-ring 21 that seals the high pressure portion and the low pressure portion is provided between the suction pipe 17 and the fixed scroll 5.

Further, as shown in FIG. 1, a space 23 (hereinafter referred to as a back pressure chamber) surrounded by the scroll compressor section 2 and the frame 11 is formed on the back surface of the end plate of the orbiting scroll 6. An intermediate pressure between the suction pressure and the discharge pressure is introduced into the pressure chamber 23 through the fine hole 6e formed in the end plate of the orbiting scroll, and an imparting force in the axial direction for pressing the orbiting scroll 6 against the fixed scroll 5 is applied. There is.

The lubricating oil 24 is stored in the bottom portion of the closed container 1. The lubricating oil 24 is formed by the differential pressure between the high pressure in the closed container and the intermediate pressure in the back pressure chamber 23. After being sucked up to 16d, it rises in the central hole 50 in the rotary shaft 16 and is fed to the orbiting bearing 32 and the auxiliary bearing 26 to the main bearing 27 (cylindrical roller bearing portion) through the lateral hole 51. The oil supplied to the bearings 26 and 27 is the back pressure chamber 2
It is injected into the compression chamber of the scroll wrap via 3 and mixed with the compressed gas, and then discharged together with the discharge gas into the upper chamber 1a. Reference numeral 28 denotes an oil plate for forming prevention arranged on the oil surface of the lubricating oil 24.

At the bottom of the closed container 1, an oil joint means 30 for an oil take-out pipe for taking the lubricating oil 24 at the bottom out of the container.
Is provided. In addition, oil is injected into the compression chamber 8 of the scroll compressor unit 2 above the closed container 1 during compression 1
A book oil injection pipe 31 is provided. The oil injection pipe 31 communicates with the compression chamber 8 via a port 22 formed in the end plate 5a of the fixed scroll 5.

The oil take-out pipe 30 and the oil injection pipe 31 are provided with an oil cooler 33 in a pipe line.
The oil pipes 36 (36a, 36b) and the throttle portion 271 are connected to each other. With the above configuration, the electric motor rotor 3b
When the motor shaft 16b directly connected to the eccentric shaft 16a rotates and the eccentric shaft 16a rotates eccentrically, the orbiting scroll 6 passes through the orbiting bearing 32.
Makes a turning motion. Due to this turning motion, the compression chamber 8 gradually moves to the center and the volume thereof decreases. The working gas enters the suction chamber 5f through the suction pipe 17 through the suction ports 15a and 15b, and the oil that lubricates the bearings 26 and 27 passes through a minute gap or the like from the frame chamber 11f at the outer peripheral portion of the orbiting scroll end plate of the orbiting scroll 6. It flows into the suction chamber 5f and mixes with the working gas.

The working gas containing the oil passing through the bearing and the oil injected from the port 22 is compressed in the compression chamber and discharged from the discharge port 10 to the upper chamber 1a, so that the passage 1
It flows into the electric motor room 1b through 8a and 18b. The solid line arrows show the flow of the working gas, and the broken line arrows show the flow of oil. The working gas and oil flowing from the narrow passages 18a and 18b into the electric motor chamber 1b having a large space have a sharp decrease in the flow velocity and a change in the flow direction, so that most of the oil contained in the gas is separated. Part of the working gas passes through the passage 25a and the space 1c below the electric motor, and again passes through the passage 25a.
c is raised and flows out into the discharge pipe 19.

The oil flows down through the gap in the outer peripheral portion of the electric motor rotor and collects at the bottom of the closed container 1. The lubricating oil 24 accumulated at the bottom of the closed container 1 flows into the oil take-out pipe 30 due to the pressure difference between the pressure (discharge pressure) in the closed container 1 and the pressure in the compression chamber 8 in which the port 22 is open. It flows from the portion 30a into the oil take-out pipe 30. Oil removal pipe 3
The oil that has flowed into 0 reaches the oil cooler 33 through the oil injection pipe 36, is appropriately cooled there, and then is injected into the compression chamber 8 through the oil injection pipes 36, 36b, 31 and the port 22. . The oil injected into the compression chamber is
It serves to cool the working gas in the compression chamber and to lubricate sliding parts such as the scroll wrap tip.

After this oil is compressed together with the working gas, it is discharged from the discharge port 10 into the upper chamber 1a, and is separated from the working gas in the electric motor chamber 1b in the same manner as described above, and is collected at the bottom of the closed container 1. In addition, the oil supply to the bearings 32, 26, 27 is performed by the oil suction pipe 16d and the rotary shaft 16 by the pressure difference between the pressure in the closed container 1 and the pressure in the back pressure chamber 23 (intermediate pressure). This is done via passageway 50. The present invention is also applied to a low-pressure chamber type helium scroll compressor in which the inside of the chamber has a suction pressure atmosphere and a low pressure. That is, in that case, the oil separated from the oil separator means (not shown) installed outside the compressor is cooled by an external oil cooler (not shown),
The cooling oil is connected from the oil injection pipe to the oil injection mechanism portion of the invention of the scroll compressor portion in the same manner as that shown in FIG.

An embodiment of the first invention according to claim 1 will be described with reference to FIGS. 1 to 3. In FIG. 1, the working gas is helium gas, and an oil injection port 22 provided in the end plate portion 5 a of the fixed scroll 5 penetrating the closed container 1 through an oil injection pipe 31 for cooling the working helium gas.
The oil injection port 22 is connected to the opening shown in FIG.
As shown in, at the position where the winding angle of the scroll wrap is approximately 120 ° in addition to two turns from the beginning of winding, the scroll wrap is opened so as to face the tooth top surface of the wrap 6b of the orbiting scroll 6. In order to enhance the cooling effect on the compressed helium gas in the compression process of the helium compressor, the oil injection port 22 is provided at a substantially central portion of the lap tooth groove portion groove width Dt so that cooling can be performed from the time of the suction process of the working helium gas. The opening provided is in a position that always maintains communication with the compression chamber 8, and is also in a position that intermittently communicates with the suction chamber 5f at the outer peripheral portion of the scroll wrap due to the orbiting motion of the orbiting scroll. It is configured with an oil injection mechanism that is configured like this. In the present embodiment, the oil injection port 22 is a single port, and when the hole diameter is do and the scroll wrap thickness is t, (do-t) / t
Is set within the range of the following formula. 0.7 ≦ (do-t) /t≦1.5 By changing the expression, it can be rewritten as 1.7 ≦ (do / t) ≦ 2.5.

The range of the dimensionless value represented by (do-t) / t is a value verified by experiments, and 0.7≤ (d
The hole diameter do is set so as to be within the range shown by (o-t) /t≤1.5. Note that Dt shown in FIG.
The groove width dimension is shown. As one design example, Dt =
It can raise 3.6t. Even when a large amount of oil injection due to the differential pressure is injected, the gas in the injection pipe easily escapes from the hole 22 within the range of the dimensionless value that has risen, and the gas accumulates in the pipe 36, 31. We were able to find out that the phenomenon could be resolved by visualizing the inside of the pipe. Therefore, the flow of oil is smooth, the flow of injection oil is uniform, the impact force does not act on the pipe, and the pipe vibration is greatly reduced. It was also found that the compressor noise also had the effect of reducing it by several decibels.

The operation and effect of the embodiment of the first invention will be described with reference to FIGS. 7 and 8. In FIG. 7, the horizontal axis represents the injection oil amount Qin (l / min) and the vertical axis represents the noise level (dB) of the compressor alone, and the conventional machine and the machine of the present invention are compared. As Figure 7 shows,
In the example machine of the present invention, in the stage where the injection oil amount is low, not only the effect of noise reduction is already recognized, but
It can be seen that the influence of the injection noise amount on the compressor noise level is smaller than that of the conventional compressor even when the injection oil amount is high.

In FIG. 8, the horizontal axis represents the dimensionless value (do-t) / t in the present invention, and the vertical axis represents the performance of the machine of the present invention and the pipe vibration level, and 0.7 ≦ (do -T) /
Pipe vibration level (and noise level) when t ≦ 1.5
And shows that it is optimal in terms of both compressor performance.

Range of dimensionless value 0.7≤ (do-t) / t
≦ 1.5 is, as described above, 1.7 ≦ do / t ≦ 2.
Although it can be replaced with 5, when do / t = 1.7 is calculated by the example of the groove width Dt = 3.6t of the scroll wrap, do becomes about 47% of the groove width Dt, and do / t
= 2.7 is calculated to be about 69% of the groove width Dt.

That is, the fact that the dimensionless value in the present invention becomes a small value less than 0.7 means that the hole diameter do is the groove width D.
This means that the hole diameter is smaller than 47% of t, and in that case, the impact force of the pipe becomes large, which is not preferable in terms of reliability. On the other hand, if the dimensionless value becomes a large value exceeding 1.5, it means that the hole diameter do is a large hole diameter exceeding 69% of the groove width Dt, and in that case, the volume efficiency tends to decrease. , Resulting in reduced compressor performance.

FIG. 4 shows an embodiment in which the oil injection port 221 is provided at a position close to the center of the wrap in terms of a wrap angle of about 60 ° when compared with the oil injection port 22 shown in FIG. An example is shown. In the present embodiment, the hole position of the oil injection port 221 is not in communication with the suction chamber 5f side during the orbiting motion of the orbiting scroll, and is always in the middle of compression both inside and outside the orbiting scroll wrap. The oil is injected into the compression chamber of.

The oil injection port 221 shown in FIG. 2 connected to the pipe portion of the oil injection pipe is opened so as to face the wrap tooth tip surface of the orbiting scroll, and substantially the tooth groove portion of the fixed scroll wrap is formed. Although it is provided in the central portion, in the first invention according to claim 1, the hole position of the oil injection port 22 is not particularly limited,
It may be at any position in the lap tooth groove (bottom surface). That is, as the hole diameter do of the port 22 increases, the limitation of the hole position becomes more permissible in terms of performance, and the dimensionless value is 0.7 ≦ (do−
The configuration satisfying t) /t≦1.5 has an important meaning.

5 and 6 show another embodiment. As shown in both figures, two oil injection ports 22 are provided which penetrate the oil injection pipe 31 into the closed container 1 and are provided on the end plate portion of the fixed scroll 5 at a winding angle of about 15 ° apart from each other.
2, 223, the openings of the two oil injection ports are opened facing the wrap tooth tip surface of the orbiting scroll, and the hole diameters of the oil injection ports 222, 223 are smaller than the wrap thickness t. Two large lap tooth grooves are provided almost along the center.

As a result, the outgassing action of the helium gas mixed in the pipes 31 and 36 can be greatly improved.
A single joint means (block body) 224 that connects the two ports 222, 223 and the single oil injection pipe 31 is provided in the fixed scroll end plate portion 5a via an O-ring 230 that serves as a sealing means. Port 22
The hole diameters do of Nos. 2 and 223 are set so that the injection effective area is equivalent to the single port 22 described in the first embodiment of the invention, and the hole diameter is smaller than that of the single port. It is set to be larger than the thickness t.

With this structure, the flow resistance of the injection pipe portion is reduced, so that the injection flow rate is increased and the cooling effect of the helium gas and the entire compressor is enhanced.

[0034]

According to the present invention, since the noise of the compressor and the vibration of the injection pipe are reduced, the reliability of the compressor can be greatly improved and the quality can be improved. Further, since the flow resistance of the injection pipe section is reduced, the injection oil amount is increased, and the cooling action of the helium gas and the entire compressor is enhanced. Therefore, there is an effect that the cooling action on the cylindrical roller bearing portion 27 used in the main bearing is promoted, the temperature of the portion is lowered, and the life of the cylindrical roller bearing portion 27 can be greatly extended due to an increase in oil viscosity. . As a result, the reliability of the compressor as a whole can be greatly improved.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view and an oiling system diagram showing an embodiment of an oiling type hermetic scroll compressor of the present invention.

FIG. 2 is a plan view of a fixed scroll.

FIG. 3 is a vertical sectional view of a fixed scroll.

FIG. 4 is a plan view of a fixed scroll.

FIG. 5 is a plan view of a fixed scroll.

6 is an enlarged partial vertical cross-sectional view of the periphery of the oil injection pipe section 31 of FIG.

FIG. 7 is an explanatory diagram showing the operation and effect of the present invention.

FIG. 8 is an explanatory diagram showing the operation and effect of the present invention.

[Explanation of symbols] 1 closed container 1a Upper chamber 1b Electric motor room 2 Scroll compressor section 3 Electric motor section 3a Electric motor stator 3b electric motor rotor 5 fixed scroll 5a Fixed scroll end plate 5b wrap 5f inhalation chamber 6 orbiting scroll 6a Orbiting scroll end plate 6b wrap 6c Boss 10 outlets 11 frames 12 Oldham Organization 15 suction port 16 rotation axes 16a Eccentric shaft 16b electric motor shaft 17 Inhalation tube 18a, 18b passage 19 Discharge pipe 25 gap 21 O-ring 22 ports 22 Oil injection port 24 Lubricating oil 26 Auxiliary bearing 27 Main bearing 271 throttle 28 oil plate 30 Oil joint means 31 oil injection pipe 32 slewing bearing 33 Oil cooler 36 oil injection pipe 36a Oil piping

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor, Yasushi Izu             Hitachi, Ltd. 390 Muramatsu, Shimizu City, Shizuoka Prefecture             Air conditioning system Shimizu Production Headquarters F term (reference) 3H029 AA02 AA14 AB04 BB01 BB21                       BB44 CC04                 3H039 AA06 AA12 BB02 BB05 BB11                       CC03 CC42

Claims (4)

[Claims] 1. A orbiting scroll in which a fixed scroll and an orbiting scroll, in which a spiral wrap is upright on a disk-shaped end plate, are engaged with each other with the wraps inward, and are engaged with an eccentric mechanism that connects the orbiting scroll to a rotary shaft. Circulates the fixed scroll without rotating, and the fixed scroll has a discharge port opening in the center and a suction port opening in the outer periphery. A scroll compressor configured to move around a compression chamber formed by both scrolls to compress the working gas by reducing the volume and discharge the compressed working gas from a discharge port to a discharge pipe. The working gas is helium gas, and an oil injection pipe for cooling the helium gas is connected to an oil injection port provided on the end plate portion of the fixed scroll. In the helium scroll compressor, the opening of the oil injection port is opened to face the wrap tooth tip surface of the orbiting scroll, and the oil injection port is provided in the lap tooth groove portion. The injection port is a single port, and when the hole diameter is do and the scroll wrap thickness is t,
A scroll compressor for helium, characterized in that a dimensionless value (do-t) / t is set in the range of the following equation. 0.7 ≦ (do-t) /t≦1.5 2. A scroll compressor unit and an electric motor unit are housed in a hermetic container, and the scroll compressor unit includes a fixed scroll and an orbiting scroll that wrap a spiral wrap upright on a disk-shaped end plate. Engage with each other inside and engage the orbiting scroll with the eccentric mechanism that is connected to the rotating shaft to make the orbiting scroll orbit with respect to the fixed scroll without rotating. With a suction port that opens to the
The working gas is sucked from the suction port, and the working chamber is moved around the compression chamber formed by both scrolls with the orbiting motion of the orbiting scroll to reduce the volume and compress the working gas, and the working gas is sealed from the discharge port. A hermetic scroll compressor that discharges into a container chamber and further discharges to the outside through a discharge pipe, wherein the working gas is helium gas, and an oil injection pipe for cooling the helium gas is sealed. The container is penetrated and connected to an oil injection port provided in the end plate portion of the fixed scroll, and the opening of the oil injection port is
In a hermetic scroll compressor in which the oil injection port is provided so as to face the wrap tooth tip surface of the orbiting scroll and the oil injection port is provided in the lap tooth groove portion, the oil injection port has a hole diameter thereof. The single port described above is set to be larger than the wrap thickness t so that the effective injection area becomes equivalent, and a plurality of lap tooth grooves are provided substantially at the center, and the plurality of ports and one oil injection are provided. A hermetic scroll compressor for helium, wherein one joint means for communicating with a pipe is provided on a fixed scroll end plate portion through a sealing means. 3. A scroll compressor unit and an electric motor unit are housed in a hermetic container, and the scroll compressor unit includes a fixed scroll and an orbiting scroll that wrap a spiral wrap upright on a disk-shaped end plate. Engage with each other inside and engage the orbiting scroll with the eccentric mechanism that is connected to the rotating shaft to make the orbiting scroll orbit with respect to the fixed scroll without rotating. With a suction port that opens to the
The working gas is sucked through the suction port, moved around the compression chamber formed by both scrolls to reduce the volume and compresses the working gas, and the compressed working gas is discharged through the discharge port into the closed container chamber, and further discharged. A hermetic scroll compressor configured to discharge to the outside of a device through a pipe, wherein the working gas is helium gas, and the fixed scroll is formed by penetrating an oil injection pipe for cooling the helium gas into a hermetic container. Is connected to an oil injection port provided on the end plate portion of, and the opening of the oil injection port is opened facing the lap tooth tip surface of the orbiting scroll, and the oil injection port is formed in the lap tooth groove portion. In the hermetic scroll compressor provided, the oil injection port is provided as a single port at substantially the center of the lap tooth groove portion, and the hole diameter d of the port is provided.
and the scroll wrap thickness is t, the dimensionless value (do-t) / t is set in the range of the following formula: A hermetic scroll compressor for helium. 0.7 ≦ (do-t) /t≦1.5 4. An oil injection pipe is connected to an oil injection port provided in the end plate portion of the fixed scroll by penetrating the airtight container, and the opening of the oil injection port has a wrap tooth tip surface of the orbiting scroll. The oil injection port is provided substantially at the center of the lap tooth groove, and the opening of the port is in a position that always maintains communication with the compression chamber. The helium scroll compressor according to any one of claims 1 to 3, further comprising an oil injection mechanism arranged to intermittently communicate with a suction chamber at an outer peripheral portion of the scroll wrap due to movement. .