JPH04321788A - Horizontal scroll compressor for helium - Google Patents

Abstract

PURPOSE:To secure the reliability of the whole compressor by properly controlling the reduction of the noise and the oil level in a chamber of a horizontal closed type scroll compressor for helium used in a helium refrigerator. CONSTITUTION:In order to smoothly move the oil separated out of gas in a discharging chamber to the oil reservoir 34 in the electric motor chamber 3 next to the discharging chamber, the cross sectional area of an oil passage 50 connecting both chamber to the outer edge section below a fixed scroll 1 and a frame 15 is set so as to be 0.2 to 5 times as much as the cross sectional area of the gas passage 26 provided in the outer edge section above the fixed scroll 1 and the frame 15. By this constitution, the noise and reliability of the compressor can be substantially improved, and by reducing the quantity of oil discharge of the compressor, the quality of a compressor for helium can be improved.

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 for compressing helium gas used in helium refrigeration equipment.

0002

[Prior Art] A horizontal hermetic scroll compressor for helium gas compression used in a conventional helium refrigeration system is
It utilizes a structure similar to the horizontal scroll compressor for refrigeration and air conditioning applications disclosed in Japanese Patent Application Laid-Open No. 61-212689. That is, a fixed scroll and an orbiting scroll serving as a compression element are provided in a closed container, and a gas discharge chamber and an electric motor chamber are partitioned by a frame toward an opposite side end of the closed container. The axial center of a crankshaft driven by an electric motor in the electric motor chamber for driving the orbiting scroll is set in the horizontal direction. Further, an oil reservoir is provided at the bottom of the gas discharge chamber and the motor chamber, and an oil supply pipe for supplying lubricating oil to the bearing of the compressor is opened into the oil in the oil reservoir at the bottom of the motor chamber. Furthermore, a gas passage is provided at the upper outer edge of the fixed scroll and the frame to communicate the gas discharge chamber and the motor room, and an oil passage is provided at the lower outer edge of the fixed scroll and the frame to communicate the gas discharge chamber and the motor room. , 0 of the cross-sectional area of the gas passage
．． It is set to about 1x. When used for helium gas compression, in addition to the above configuration, in order to cool the compressed gas, the oil in the oil reservoir at the bottom of the motor room is passed through an oil cooler and a throttle device to the suction pipe of the compressor or to the compressor. It is equipped with an oil injection mechanism that injects oil into the compression chamber in the middle.

0003

[Problems to be Solved by the Invention] In the prior art, as shown in FIG. The surface height had risen to the vicinity of the discharge port 2 of the fixed scroll. In such a case, the helium gas flows out from the discharge port 2 into the oil 34a in the discharge chamber 32, so that the so-called gas hits the oil. For this reason, the discharge chamber 32 generates sound (noise) in a relatively low frequency range.

A scroll compressor for helium gas compression is provided with an oil injection mechanism to cool the compressed gas, and the amount of injected oil is several tens to several times the mass flow rate of the helium gas circulation flow rate. It's a hundred times the amount. The amount of oil injected is several times to several tens of times the amount of oil supplied to the bearings of conventional scroll compressors for refrigeration and air conditioning. In the prior art,
It utilizes the structure of a scroll compressor for refrigeration or air conditioning, and the oil passages 27 and 50 that communicate the oil sump in the discharge chamber 32 and the oil sump in the motor room 33 are small, such as semicircular arcs. Since the cross-sectional area of the oil passage was not large enough, the oil did not flow smoothly from the discharge chamber 32 to the motor chamber 33, and the oil level in the discharge chamber 32 rose.

In addition to the above-mentioned noise problem, the motor room 33
When the oil level inside the compressor decreases, the amount of oil supplied to the bearing portion through the oil supply pipe 23 becomes insufficient, which also causes a problem in that the reliability of the compressor decreases. Furthermore, when the oil level in the discharge chamber 32 rises, the separation efficiency for separating oil from the gas in the discharge chamber decreases, and the amount of oil flowing out of the sealed container increases, causing the amount of oil in the oil reservoir to decrease. This also leads to the problem that the reliability of the compressor decreases.

An object of the present invention is to reduce the noise of a horizontal hermetic scroll compressor for helium used in a helium refrigeration system, and to ensure the reliability of the compressor by properly managing the oil level in the hermetic container. be.

[0007]

[Means for Solving the Problems] In the present invention, in order to smoothly move the oil separated from the gas in the discharge chamber to the oil reservoir in the motor room, as shown in FIG. The cross-sectional area of the oil passage provided at the lower outer edge is set to be 0.2 to 5 times the cross-sectional area of the gas passage provided at the upper outer edge of the fixed scroll and frame.

[0008]

[Operation] In the present invention, 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 cross-sectional area of the oil passages 27 and 50 that communicate the two chambers is reduced. It is set to 0.2 to 5 times the cross-sectional area of the gas passages 26, 15f. Therefore, the height of the oil level of the oil 34a in the discharge chamber 32 can be lowered, and the helium gas discharged from the discharge port 2 will not hit the oil, resulting in a significant reduction in noise. In addition, since the oil level of the oil 34b in the motor chamber 33 does not decrease, the oil can be reliably supplied to the oil supply pipe 23 that supplies oil to the bearing, which reduces the reliability of the compressor such as the aforementioned lack of oil supply. is resolved.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention is shown in FIGS. 1 to 6. FIG. 1 is a longitudinal sectional view of a horizontal hermetic scroll compressor showing the overall configuration of the present invention, and shows a case in which oil is poured into a compression chamber during compression to cool compressed gas.

[0010] This compressor is a horizontal hermetic compressor that employs a high-pressure chamber system in which the inside of a hermetic container is in a high-temperature, high-pressure atmosphere.

In FIG. 1, a compressor section 100 is housed at the right end of the airtight container 31, and an electric motor section 17 is housed at the left end. The scroll compression element section is equipped with an oil injection mechanism connected to an oil injection pipe 40 for cooling the working helium gas, and the gas discharge chamber 32 and motor room 33 to frame 1
5 and an oil reservoir 34 below both chambers.
A horizontal hermetic scroll compressor is disclosed in which the axis of a crankshaft 19 driven by the electric motor 17 for driving the orbiting scroll 5 is set in the horizontal direction.

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 disc-shaped end plate 1a and a wrap 1b standing upright thereon and formed into an involute curve or a curve similar to this, and a discharge port 2 at the center of the wrap 1b. , 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. The scroll wrap is formed by an involute curve as described above, and the number of wrap turns is approximately 4, for example. FIG. 2 is a partial sectional view showing the structure around the discharge chamber 32. The orbiting scroll member 5 includes a disc-shaped end plate 5a, a wrap 5b standing upright thereon and formed in the same shape as the wrap of the fixed scroll, and a boss 5c formed on the wrap surface of the end plate. 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.
A force is obtained to press the orbiting scroll 5 toward 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. 1 to 5, a suction pipe 11 is connected to the suction ports 3 and 3a of the fixed scroll member 1 through a closed container 31b, and a discharge chamber 32 having an open discharge port 2 is connected to the suction pipe 11 through the closed container 31b. The motor is connected to the electric motor through the helium gas passage 26 (26a, 26b) provided at the upper outer edge of the fixed scroll member 1 and the helium gas passage 15f (15g, 15h) provided at the upper outer edge on the frame 15 side, which coincides with the helium gas passage 26 (26a, 26b). It communicates with room 33. This motor chamber 33 communicates with a discharge pipe 16 that passes through a side end 31c of the closed container 31. and,
Oil passage 27 provided at the lower outer edge of fixed scroll member 1
(27a, 27b) and communicate with the oil reservoir 34 on the motor chamber 33 side via an oil passage 50 provided at the lower outer edge on the frame 15 side in agreement with these. 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.

Next, an oil injection mechanism for cooling compressed gas will be explained with reference to FIG.

An oil injection pipe 40 is connected to an oil injection hole 1w in the tooth groove of the end plate 1a of the fixed scroll 1 so that oil can be injected into the compression chamber 7 formed by the scroll members 1 and 5. On the side cover 31c of the closed container 31 on the side of the motor room 33, there is an oil outlet pipe 67a curved downward for taking out oil from the oil reservoir 34 at the lower part of the chamber 33, which is connected to the oil pipe outside the machine through the oil outlet 67. 51, and this oil pipe 51 is connected to a throttle device 8 via an oil cooler 80.
1, and side cover 3 on the compressor side of the sealed container 31.
It is connected to the oil injection pipe 40 passing through 1b. Here, we will briefly explain the flow of gas and oil in a closed type machine. Helium gas is directly sucked into the scroll compression element section from the suction pipe 11 through the suction chamber 22, and the scroll section 1,
5, the pressure and temperature are gradually increased. As described above, the amount of oil injected is several tens to hundreds of times larger in mass flow rate than the helium gas flow rate.

The gas flows out into the discharge chamber 32 from the discharge port 2 in the center of the fixed scroll 1 along with the cooling oil injected through the oil injection hole 1w during compression. Further, the gas flows into the motor chamber 33 via the gas passages 26 and 15f above the fixed scroll 1, and flows out from the discharge pipe 16. Note that most of the oil (injected oil and bearing oil) mixed with the gas in the compression chamber is separated from the gas in the discharge chamber 32.

As shown in FIG. 3, in order to facilitate the movement of the oil 34a in the discharge chamber 32 into the motor chamber 33, the cross-sectional area of the oil passages 27, 50 connecting the two chambers is changed to the gas passage 26, 50.
It is set to 0.2 to 5 times the cross-sectional area of No. 15 (in FIG. 3, it is about 0.5 times).

This is because the mass flow rate of helium gas is small, so 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 so, the separated oil 34a smoothly moves to the motor chamber 33 side, and as shown in FIGS. 1 and 2, the oil 34a in the discharge chamber 32
Increase in the oil level height of a and the oil 34b in the motor room 33
It is possible to prevent a drop in the oil level height in both chambers, to equalize the oil level height in both chambers, and to appropriately manage the oil level. Therefore, the helium discharged from the discharge port 2 does not hit the oil, and noise can be significantly reduced. In addition, the electric motor room 33
Since the oil level of the oil 34b inside can be prevented from decreasing, the oil can be reliably supplied to the oil supply pipe 23 that supplies oil to the slewing bearing, etc., and the above-mentioned problems related to the decrease in reliability of the compressor, such as insufficient oil supply, can be solved. It will be resolved. In addition, oil can be reliably distributed to the oil injection piping route. Returning to FIG. 1, the oil 34b in the oil reservoir 34 is led out of the machine again from the lower end of the closed container side end 31c described above, and is again injected into the compression chamber 7 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 communicates the rotating shaft 19 with 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 downstream turning bearing 39 (
1) and around the main bearing 46, an intermediate pressure P, which is a pressure in the middle of compression, is caused by the pores 29 provided in the rotating mirror plate 5a.
m, the lubricating oil 34b in the oil reservoir 34 at the bottom of the container flows into the oil supply pipe 23 due to the pressure difference (Pd-Pm).
rise within.

FIG. 6 shows another embodiment of the fixed scroll 1 in which a plurality of oil passages 27 are provided. In this case, the cross-sectional area of the oil passage 27 (27a, 27b) can be further increased (in FIG. 6, the cross-sectional area of the oil passage 27 is about 1.5 times that of the gas passage 26). Therefore,
1 and 2, since the flow of oil from the discharge chamber 32 to the motor chamber 33 can be made smoother, the amount of injected oil injected from the oil injection hole 1w can be increased due to changes in operating conditions, etc. Even if the oil sump 34 at the bottom of the closed container
It is possible to appropriately manage the oil level height of the engine, thereby ensuring noise reduction and compressor reliability.

[0021]

[Effects of the Invention] The present invention has the following effects.

(1) The oil level in the discharge chamber can be controlled at an appropriate level, and the gas will not hit the oil, so the noise of the compressor can be significantly reduced.

(2) The oil can be smoothly moved from the discharge chamber to the motor room, and the oil level in the motor room used for lubricating the bearing of the compressor can be controlled at an appropriate level. The reliability of the compressor can be ensured.

(3) The oil separation effect in the discharge chamber is greatly improved, and the amount of oil flowing out of the closed container can be reduced, so the reliability of the compressor is further improved.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a horizontal hermetic scroll compressor for helium showing the overall configuration of the present invention.

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

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

FIG. 4 is a plan view showing an example of the frame 15.

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

FIG. 6 is a plan view showing another embodiment of the fixed scroll 1 in which a plurality of oil passages are provided.

FIG. 7 is a partial cross-sectional view showing the structure around the discharge chamber 32 of the prior art.

FIG. 8 is a plan view showing a fixed scroll in a fluorocarbon refrigerant such as a conventional refrigeration application.

[Explanation of symbols]

1... Fixed scroll, 2... Discharge port, 5... Orbiting scroll, 15... Frame, 15f, 26... Gas passage, 17... Electric motor, 27, 50... Oil passage, 32... Discharge port, 33... Motor room, 34... Oil Reservoir, 34a, 34b...Oil.

Claims (2)

[Claims] Claim 1: A fixed scroll and an orbiting scroll serving as a compression element are provided in a closed container, and a gas discharge chamber and a motor room are partitioned by a frame toward an opposite side end of the closed container. The axis of the crankshaft, which is driven by the electric motor for driving the orbiting scroll, is set horizontally, and an oil reservoir is provided at the bottom of the gas discharge chamber and the motor chamber, so that the oil at the bottom of the motor chamber is An oil injection mechanism is provided for injecting oil in the reservoir into the suction pipe of the compressor or the compression chamber during compression through an oil cooler and a throttle device, and the gas discharge chamber and electric motor are provided at the upper outer edge of the fixed scroll and frame. In a horizontal scroll compressor for helium, the helium horizontal scroll compressor is provided with a gas passage that communicates between the chambers, and an oil passage that communicates the gas discharge chamber and the electric motor chamber at the lower outer edge of the fixed scroll and frame. A horizontal scroll compressor for helium, characterized in that the cross-sectional area of the gas passage is set to 0.2 to 5 times. 2. The horizontal scroll compressor for helium according to claim 1, wherein a plurality of oil passages are provided at the lower outer edge of the fixed scroll and the frame.