JPH04301191A - Horizontal closed type scroll compressor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a horizontal hermetic scroll compressor used in a helium refrigeration system.

0002

[Prior Art] The structure of a horizontal hermetic scroll compressor for helium used in a conventional helium refrigeration system is as follows:
For example, as described in Japanese Patent Application Laid-Open No. 61-212689, from the side end of the closed container toward the opposite side end,
A gas discharge chamber and an electric motor chamber are partitioned and formed by a frame, and an oil reservoir is provided below both chambers, and the axis of the crankshaft driven by the electric motor for driving the orbiting scroll is aligned horizontally. It is configured in a horizontal format.

0003

A hermetic scroll compressor for helium used in a helium refrigeration system has an oil injection structure for cooling gas and an electric motor. This injection oil volume is tens of times (mass flow rate) or hundreds of times the helium circulation flow rate, and the oil is injected at a flow rate several hundred times higher than that of conventional air conditioning compressors. It turns out. A horizontal hermetic scroll compressor for helium in which this phenomenon occurs to an extreme extent will be described. The above-mentioned conventional technology is based on the height of the oil 34a in the discharge chamber 32 (oil level height) and the motor chamber 33 as shown in FIG.
The height of the oil 34b inside the discharge chamber 32 (oil level height) was significantly different, and the height of the oil 34a inside the discharge chamber 32 was located around the discharge hole 2. In such a case, the helium gas is discharged from the discharge chamber 32.
The oil 34a inside will flow out from the discharge hole 2,
So-called gas hits oil. Therefore, the discharge chamber 32 generates sound (noise) in a relatively low frequency range. This difference in oil level height can be seen, for example, in the case of refrigeration, as shown in the conventional example shown in Fig. 9. As implemented in a horizontal scroll compressor for air conditioning, the amount of oil that is ejected from the discharge hole 2 together with gas and accumulated in the discharge chamber 32 is reduced by the amount of oil in the oil reservoir in the discharge chamber 32 and in the motor chamber 33. The oil passage (
27 etc.) is caused by the passage area not being large enough, such as a small semi-circular passage shape. Experiments have shown that in refrigeration and air conditioning applications, the viscosity of the oil decreases due to the dilution effect of the oil refrigerant, making it difficult for the above-mentioned phenomenon to occur.

Furthermore, in order to reduce the size of the lateral dimension L1 of the discharge chamber 32, the chamber inner diameter ratio L1/Dc=0.13 (Dc
refers to the chamber inner diameter. ) is relatively small, the discharge pulsation accompanying the gas flow and the air column resonance within the discharge chamber 32 are correlated to generate sound (noise) with an even stronger sound pressure level. Horizontal hermetic scroll compressors for helium are used in the field of medical equipment among helium refrigeration systems, and reducing compressor noise is a major technical issue. Also, the height of the oil 34a in the discharge chamber 32 (
If the height of the oil 34b in the motor chamber 33 (oil level height) is significantly different from the height of the oil 34b in the motor chamber 33, the height of the oil 34b in the motor chamber 33 will further decrease, making it difficult to lubricate bearings, etc. This also leads to problems such as a decrease in the reliability of the compressor, such as a lack of oil to the oil supply pipe 23.

The purpose of the present invention is to provide a horizontal hermetic scroll compressor for helium used in a helium refrigeration system, and for reasons such as the low temperature inside the compressor during transient operation at the initial stage of startup. The project also targets horizontal hermetic scroll compressors for refrigeration and air conditioning applications, which are facing issues, and improves the overall reliability of the compressor by reducing noise in horizontal hermetic scroll compressors and properly managing the oil level in the chamber. It is to ensure that

[0006]

[Means for Solving the Problems] In order to achieve the above object, the present invention sets the lateral dimension L2 of the discharge chamber 32a to a chamber inner diameter ratio of L2/Dc=0.20 to 0.25 or more. be.

[0007] Also, in order to smoothly move the oil separated from the gas in the discharge chamber to the oil sump in the adjacent motor room,
The oil passage connecting both chambers is set at the lower outer edge of the fixed scroll and frame to be as wide as or wider than the gas passage provided at the upper outer edge of the fixed scroll and frame. be.

[0008]

[Operation] As shown in FIGS. 1 to 6, in order to make it easier for the oil 34a in the discharge chamber 32 to move into the motor chamber 33, the oil passages 27 and 50 connecting both chambers are connected to the gas passage 26,
15f, the height of the oil 34a in the discharge chamber 32 (oil level height) and the height of the oil 34b in the motor chamber 33 (oil level height) are made equal. can be leveled. Therefore, the helium gas discharged from the discharge hole does not hit the oil.

Furthermore, since the lateral dimension L2 of the discharge chamber 32 is relatively large, with the chamber inner diameter ratio being around L1/Dc=0.20, the discharge pulsation accompanying the flow of gas and the air inside the discharge chamber 32 are reduced. Column resonance can be avoided. Therefore, the overall noise of the scroll compressor can be significantly reduced. Also, since the height of the oil 34a in the discharge chamber 32 (oil level height) and the height of the oil 34b in the motor chamber 33 (oil level height) are at the same level, it is necessary to oil the bearings etc. The oil can be reliably supplied to the oil supply pipe 23, and the above-mentioned problems related to the decrease in reliability of the compressor, such as the lack of oil supply, can be solved.

0010

[Embodiment] An embodiment of the present invention will be explained with reference to FIGS. 1 to 7. FIG. 1 is a longitudinal sectional view showing the overall structure of a horizontal hermetic scroll compressor according to the present invention. This compressor is a horizontal hermetic compressor that uses a high-pressure chamber system in which the inside of the chamber is in a high-temperature, high-pressure atmosphere.

In FIG. 1, the compressor section 100 is on the right side of the side end inside the closed container 31, and the electric motor section 17 is on the opposite left side.
is stored. The scroll compression element section is equipped with an oil injection mechanism connected to the oil injection pipe 40 for cooling the working helium gas, and the gas is injected from the side end of the closed container 31 toward the opposite side end. Discharge chamber 32
(32a) and a motor chamber 33 are partitioned by a frame 15, and an oil reservoir 34 is provided below both chambers. The axis is set horizontally.

The compressor section 100 has a fixed scroll member 1 and an orbiting scroll member 5 that are engaged with each other to form a compression chamber (closed space) 7. As shown in FIG. 3, the fixed scroll member 1 consists of a disk-shaped end plate 1a and a wrap 1b standing upright thereon and formed in an involute curve or a curve approximating it, and a discharge port 2 at the center thereof. , an inlet 3 is provided on the outer periphery. FIG. 3 shows a plan view of the fixed scroll 1 provided with oil injection holes 1w. Scroll wrap is
An example is shown in which the winding is formed by an involute curve as described above and the number of wraps is approximately 4. The orbiting scroll member 5 includes a disc-shaped end plate 5a, a wrap 5b standing upright on the end plate and formed in the same shape as the wrap of the fixed scroll, and a boss 5c formed on the opposite surface of the end plate.
It consists of A thin hole 29 is provided in the end plate 5a of the orbiting scroll 5, so that the pressure in the back pressure chamber 36 existing on the back side of the end plate of the orbiting scroll 5 is set to an intermediate pressure between the suction pressure and the discharge pressure, and the orbiting scroll 5 is A force is obtained to press the fixed scroll 1 side.

[0013] The frame 15 has a bearing part formed in the center,
A rotating shaft 19 is supported by this bearing portion, and an eccentric shaft 20 at the tip of the rotating shaft is inserted into the boss 5c so as to be able to rotate. Further, the fixed scroll member 1 is fixed to the frame 15 by a plurality of bolts, and the orbiting scroll member 5 is fixed to the key pedestal portion 15 of the frame 15 by an Oldham mechanism 10 consisting of an Oldham ring and an Oldham key.
The orbiting scroll member 5 is supported by the fixed scroll member 1 and is formed to perform an orbiting motion without rotating on its axis.

As shown in FIGS. 2 to 5, a suction pipe 11 having an elbow structure is connected to the suction ports 3 and 3a of the fixed scroll member 1 through an airtight container 31, and a discharge hole 2 is opened. The discharge chamber 32 is connected to a helium gas passage 26 (26a, 26b) provided at the upper outer edge of the fixed scroll member 1, and a helium gas passage 15 (15f) provided at the upper outer edge on the frame 15 side, matching the helium gas passage 26 (26a, 26b). , 15h) and communicates with the motor room 33. The electric motor chamber 33 communicates with a discharge pipe 16 having an elbow structure and passing through the side end 31C (70) of the closed container 31. Oil passages 27 (27a, 27b) provided at the lower outer edge of the fixed scroll member 1
) and oil passages 50 (50a, 50b) provided on the lower outer edge of the frame 15 side to match the oil passages 50 (50a, 50b) to the motor room 3.
It communicates with the oil reservoir section 34 on the third side. Note that 34 indicates an oil reservoir at the bottom of the closed container. In the figure, solid line arrows indicate the flow direction of helium gas, and dashed line arrows indicate the flow direction of oil.

FIG. 1 shows the structure of an oil injection pipe 40 for cooling gas and an electric motor. An oil injection pipe 40 is provided with an oil injection pipe 40 so that oil can be injected into the compression chamber 7 formed by both scroll members 1 and 5.
A tooth groove portion of the end plate portion 1a of the fixed scroll 1 is connected to an oil hole 1w. On the side cover 31c of the airtight container 31 on the side of the motor room 33, there is an oil outlet pipe 67a curved downward that takes out oil from the oil reservoir 34 in the lower part of the chamber 33, and an oil outlet pipe 67a that takes oil out of the compressor through an oil outlet 67. The oil pipe 51 is connected to the oil injection pipe 40 which passes through the oil cooler 80 to the throttle part 81 and through the side cover 31b of the closed container 31 on the compressor side. ing. Here, we will briefly explain the flow of gas and oil in a hermetic compressor. Helium gas is directly sucked into the scroll compression element portion from the suction pipe 11 through the suction chamber 22, and its pressure and temperature are gradually increased by the compression action of the scroll portions 1 and 5. As described above, the amount of the injection oil is several tens (mass flow) or several hundred times the helium flow rate, and a considerably large amount of cooling oil is injected. The gas flows out from the discharge hole 2 in the center of the fixed scroll 1 into the discharge chamber 32 (32a) together with the cooling oil injected through the injection hole 1w during compression. Further, the gas flows into the motor chamber 33 via the communication passages 26 and 15 above the fixed scroll 1 and flows out from the discharge pipe 16. Note that most of the oil (injection oil and bearing oil) mixed with the gas in the compression chamber is separated from the gas in the discharge chamber 32a.

As shown in FIG. 1, the lateral dimension L2 of the discharge chamber 32a is set to a chamber inner diameter ratio of L2/Dc=approximately 0.20 (here, Dc is the chamber inner diameter) or more. This is because the oil separation efficiency in this chamber 32a is greatly improved. As shown in FIG. 3, the discharge chamber 32a
In order to facilitate the movement of the oil 34a inside the motor chamber 33, the oil passages 27 and 50 connecting both chambers are set to be as wide as or wider than the gas passages 26 and 15. Oil passage 27 (2
As shown in the figure, the width m2 of the gas passage 26b is set slightly larger than the width m1 of the gas passage 26b. Experimentally, the sizes of these oil passages 27 and 50 are preferably determined so that the oil flow rate is approximately 0.3 M/S or less. This is because there is almost no pressure difference between the two chambers and the oil viscosity is relatively high, so it is necessary to secure a large oil passage for helium. By doing this,
The separated oil 34a smoothly moves to the motor room 33 side, and as shown in FIGS. 1 and 2, the height of the oil 34a in the discharge chamber 32a (oil level height) and the motor room Oil in 33 34
The height of b (oil level height) can be set to the same level. Of course, the helium gas discharged from the discharge hole 2 will not hit the oil. Furthermore, discharge pulsation due to gas flow and air column resonance within the discharge chamber 32a can be avoided. Therefore, the overall noise of the scroll compressor can be significantly reduced. Also, since the height of the oil 34a in the discharge chamber 32 (oil level height) and the height of the oil 34b in the motor chamber 33 (oil level height) are at the same level, it is not necessary to refuel the slewing bearing. This makes it possible to reliably supply oil to the oil supply pipe 23, which solves the problem of reduced reliability of the compressor, such as the lack of oil supply described above. It also ensures that oil is distributed throughout the oil injection piping route.

As shown in FIG. 1, the oil 34 in the oil reservoir 34
b is led out of the machine again from the lower end of the chamber-side end 31c described above, and is injected into the compression chamber 7 again via the oil cooler 80. A central horizontal hole 13 is formed in the rotating shaft 19 as shown in FIG. 7 for supplying oil to each bearing section. 23 is an oil supply pipe that connects the rotating shaft 19 and the bottom oil reservoir 34. The lower end of the oil supply pipe 23 immersed in the oil reservoir 34 of the lubricating oil 34b receives a high discharge pressure Pd, while the area around the downstream swing bearing 39 (see FIG. 1) and the main bearing 46 , an intermediate pressure P which is a pressure in the middle of compression is generated by the pores 29 provided in the end plate 5a of the orbiting scroll 5.
m, the lubricating oil 34b in the oil reservoir 34 at the bottom of the container rises due to the pressure difference (Pd-Pm). In this way, each bearing portion is lubricated by approximately the differential pressure lubricating method. In addition, in the present invention, as shown by the solid line in FIG.
/Dc=0.15 or so, it goes without saying that simply setting the oil passage as shown in Figure 3 has the effect of reducing the noise described above and properly controlling the oil level in the chamber. That's true.

FIG. 6 is a partial sectional view showing the structure around the discharge chamber 32 when the oil passage shown in FIG. 3 is enlarged. In FIG. 6, in the conventional air conditioner, both chambers 32,
33 is P1>P2, and oil is pushed from the discharge chamber into the motor chamber using the differential pressure. On the contrary,
In the case of helium, the density is lower than that of fluorocarbon gas refrigerants, so the pressure loss associated with gas flow is small. Also,
The total amount of injection oil and bearing oil is several dozen times larger than that for air conditioners. Therefore, in order to move oil from the discharge chamber 32 to the motor chamber 33 by gravity, the lower communication passage (oil passage) must be made larger as described above. As described above, helium refrigerants have unique features compared to air conditioning applications that use fluorocarbon gas refrigerants.

FIG. 7 shows an embodiment in which an air column resonance type silencer 72 is installed around the discharge hole 2 of the fixed scroll 1 in the discharge chamber 32a. The tip of the silencer 72 is provided with a gap 73 for letting discharged oil escape, and circular holes 72a of appropriate size and number are provided on the cylindrical circumference. This circular hole 72a
are a gas passage and an oil passage, and it is preferable to decide the diameter and number according to the operating frequency of the compressor. With this configuration, the noise of the compressor can be further reduced significantly.
It can be a high quality compressor.

[0020]Although the explanation has focused on horizontal scroll compressors for helium use, similar functions and effects can also be applied to horizontal scroll compressors for refrigeration and air conditioning using fluorocarbon gas. There is. That is, the compressor uses fluorocarbon gas as the working gas, and the compression element section includes a fixed scroll 1 and an orbiting scroll 5.
The scrolls 1 and 5 are engaged with each other inwardly, and an Oldham mechanism consisting of an Oldham key part and a ring part is provided between a frame 15 for fixing the fixed scroll 1 and the end plate of the orbiting scroll 5. A gas discharge chamber and a motor chamber are partitioned and formed by a frame 15 toward the side end opposite to the side end of 31, and an oil reservoir is provided below both chambers.
In a horizontal hermetic scroll compressor in which the axis of the crankshaft driven by the electric motor for driving the orbiting scroll 5 is set in the horizontal direction, oil separated from the gas in the discharge chamber is transferred to the adjacent gas. Fixed scroll 1 and frame 15 are installed to allow smooth movement to the oil sump in the motor room.
Refrigeration and air conditioning characterized in that an oil passage connecting both chambers is set at the lower outer edge of the fixed scroll 1 and the frame 15 to have the same width as the gas passage provided at the upper outer edge of the frame 15. This is a horizontal scroll compressor used for

[0021]

Effects of the Invention In the horizontal hermetic scroll compressor of the present invention, the lateral dimension L2 of the discharge chamber 32a is reduced to L2 by the chamber inner diameter ratio.
/Dc is set from 0.20 to 0.25 or more, so the helium gas coming out of the discharge hole does not hit the oil, and the noise of the compressor can be significantly reduced, making it possible to use a high-quality compressor. It is effective in providing the following.

In addition, in order to smoothly move the oil separated from the gas in the discharge chamber to the oil sump in the adjacent motor chamber,
The oil passage connecting both chambers is set at the lower outer edge of the fixed scroll and frame to be as wide as or wider than the gas passage provided at the upper outer edge of the fixed scroll and frame. Therefore, the discharge pulsation accompanying the flow of gas and the discharge chamber 3
In addition, the height of the oil 34a in the discharge chamber 32 (oil level height) and the height of the oil 34b in the motor chamber 33 (oil level height) can be avoided. is at the same level, so by properly managing the oil level in the chamber and smoothing the movement of oil, the cooling effect of the circulating oil on the entire compressor is increased, ensuring the reliability of the compressor. This increases the volume of the discharge chamber and further increases the amount of oil stored in the chamber, which reduces changes in the oil level during operation and further improves the reliability of the compressor. The oil separation effect in the chamber is greatly improved, and the amount of oil flowing out of the chamber can be further reduced, which has the effect of further improving the reliability of the compressor as a whole.

[0023]

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a horizontal hermetic scroll compressor showing the overall configuration of an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing the structure around the discharge chamber 32a.

FIG. 3 is a plan view showing an embodiment of the fixed scroll 1. FIG.

FIG. 4 is a plan view and a longitudinal sectional view showing an embodiment of the frame 15.

FIG. 5 is a plan view and a longitudinal sectional view showing an embodiment of the frame 15.

FIG. 6 is a partial cross-sectional view showing the structure around the discharge chamber 32a.

FIG. 7 is a diagram showing another embodiment of the present invention, and shows a discharge chamber 32a.
FIG. 3 is a partial cross-sectional view showing the surrounding structure.

8 is a partial cross-sectional view showing the structure around the discharge chamber 32. FIG.

FIG. 9 is a diagram showing an example of the prior art, and is a plan view showing a fixed scroll in a fluorocarbon refrigerant such as for refrigeration.

[Explanation of symbols]

1... Fixed scroll, 2... Discharge hole, 5... Orbiting scroll, 17... Electric motor, 33... Motor chamber, 36... Back pressure chamber, 34
...oil reservoir, 34a...oil, 32...discharge chamber, 26...gas passage, 27...oil passage, 50...oil passage.

Claims (3)

[Claims] [Claim 1] A fixed scroll and an orbiting scroll serving as a compression element part, wherein both scrolls are engaged with each other inwardly, and between a frame for fixing the fixed scroll and an end plate of the orbiting scroll. It is equipped with an Oldham mechanism consisting of an Oldham key part and a ring part, and an oil injection mechanism connected to an oil injection pipe for cooling operating helium gas is provided in the scroll compression element part. A gas discharge chamber and a motor chamber are partitioned and formed by a frame toward the side end, and an oil reservoir is provided below both chambers, and the scroll is driven by the electric motor for driving the orbiting scroll. In a horizontal hermetic scroll compressor in which the axis of the crankshaft is set horizontally, the oil separated from the gas in the discharge chamber is smoothly moved to the oil sump in the adjacent motor room. , an oil passage connecting the two chambers is provided at the lower outer edge of the fixed scroll and the frame,
A horizontal hermetic scroll compressor, characterized in that the fixed scroll and the gas passage are set to be as wide or wider than the gas passage provided at the upper outer edge of the frame. 2. The horizontal hermetic scroll compressor according to claim 1, wherein the ratio L2/Dc is set to 0.2 or more, where L2 is the horizontal dimension of the discharge chamber 32a and Dc is the inner diameter of the chamber. 3. A cylindrical air column resonance type silencer is installed around the discharge hole of the fixed scroll in the discharge chamber 32, and a gap is provided at the tip of the silencer to let the discharged oil escape. 3. The horizontal hermetic scroll compressor according to claim 1, wherein circular holes of appropriate size and number are provided on the circumference of the cylinder.