JPH0739831B2 - Scroll fluid machinery - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement of a scroll fluid machine that applies the principle of a full-system rotary scroll compressor that rotates a drive scroll and a driven scroll.

[Conventional technology]

The principle of a scroll compressor has been known for a long time, and it is a kind of positive displacement compressor that combines a pair of spiral projections to perform a compression action. Normally, one of the spiral protrusions is fixed and the other is swung to perform the compression action, but the principle of the so-called whole system rotation type in which both spiral protrusions are rotated around their respective centers Are known, for example as disclosed in US Pat. No. 2,475,247.

FIG. 3 shows a principle diagram of this whole-system rotary scroll compressor. The drive scroll (1) makes a rotary motion about its axial center O ₁ by a drive source such as an electric motor, an engine, or a turbine. The driven scroll (2) also rotates about its axial center O ₂ in synchronism with the rotation of the drive scroll (1). The rotation of both causes the compression chamber (3) to move to the center side, and the volume thereof is gradually reduced, the pressure of the compressed gas rises, and the compressed gas is squeezed out from the discharge port (2c) as high-pressure gas.

In the state of 0 ° in Fig. 3 (a), gas is sucked into the compression chamber (3), and thereafter, as shown in (b) to (d), 0 ° → 90 ° → 180 ° → 270 ° → By rotating 360 ° (0 °),
The compression chamber (3) gradually moves toward the center and its volume decreases.
During this period, the radial seal portions (S) formed by the spiral projections (1a) and (2a) of both scrolls (1) and (2) are aligned in the radial direction and occupy a certain position in a stationary state. I know that

[Problems to be Solved by the Invention]

In the conventional scroll compressor as described above, it was extremely difficult to maintain a high degree of vacuum in the gas suction chamber on the discharge side. Therefore, there is a problem that the principle of the conventional scroll compressor cannot be applied to the vacuum pump, which is an unprecedented situation.

Therefore, when the principle of this conventional scroll compressor is applied to a vacuum pump, when the gas is compressed by the driving scroll and the driven scroll, it is said that this gas contains a gas that is easy to stare. In the compression process, the gas liquefies and melts into the oil, resulting in a significant deterioration of the oil.

The present invention has been made to solve such a conventional problem, and in a vacuum state, air is introduced into the center of the scroll during compression, and a scroll fluid machine capable of preventing liquefaction of gas is provided. To aim.

[Means for Solving the Problems]

A scroll fluid machine according to the present invention includes: a first container having an intake port; a second container airtightly coupled to the first container; and a second container having an exhaust port and containing oil, and the first container. A first scroll that is rotatably arranged and has a discharge port that communicates with the inside of the second container at a substantially axial center; a second scroll that cooperates with the first scroll to form a compression chamber; Of the first scroll and the second scroll, a drive source for rotationally driving one of the second scroll, a check valve for reversely stopping the flow path of the discharge port, the first container or the second container, and the first A vent hole that penetrates the scroll and communicates the compression chamber with the outside of the first container or the second container, and is attached to the outside opening side of the vent hole to open and close the vent hole. It is provided with an opening / closing member.

[Action]

In the scroll fluid machine according to the present invention, by opening the on-off valve of the vent at an appropriate time, the liquefied gas compressed in the compression chamber is prevented from liquefying by introducing the outside air under the vacuum state. To be done.

Example of Invention

FIG. 1 is a vertical sectional view of an embodiment of a scroll vacuum pump according to the present invention. In the figure, (1) is a drive scroll arranged in the upper part, and the spiral protrusion (1a) is provided in the disc part (1b), the discharge port (1c) is provided in the shaft center O ₁ , and the upward scroll is shown. The drive shaft (4) is brought out integrally or by fixing. (4a) is an exhaust passage communicating with the discharge port (1c) through the valve (32), (4b) is a plurality of discharge holes formed in the radial direction, and (2) is a driven scroll arranged below. ,
The spiral protrusion (2a) provided on the disc portion (2b) is combined with the spiral protrusion (1a), and the boss portion (5) is exposed at the bottom. (6) is a cylindrical container, (6a) is a suction chamber,
(7) is a bearing housing attached to the lower end of the container (6), which supports the driven scroll (2) through the bearings (18) and (19), and the O-ring is attached to the container (6) by a bolt (20). It is attached airtightly via (23). (8) is an O-ring (24) on the upper end of the container (6) with a bolt (21)
It is an upper container that is airtightly attached through the inside of which an atmospheric pressure chamber (10) is formed, and the atmospheric pressure chamber (10) is also formed.
The exhaust port (11) leading to the atmosphere is opened. (1
6) and (17) are bearings fitted in the upper container (8) to support the drive shaft (4), and (25) is a retainer, which is fixed to the upper container (8) by screws (26), 16) is supported. (14) and (15) are seals, (13) is a retaining ring that is fixed to the upper container (8) and supports the seal (14), (2)
Reference numeral 7) is a drive source electric motor, which is mounted on the upper container (8) by a bolt (22) through a flange (28).
Reference numeral (29) is a rotary shaft of the electric motor (27), and the drive shaft (4) is connected by a shaft coupling (30). (12) is attached to the container (6), and is an inlet for drawing a vacuum from an object to be vacuumed, and (32) is a valve which is pressed by a spring (31).
Reference numeral (33) is a joint and is positioned by a key or a protrusion (35) provided on the drive scroll (1) and a heel (34). The ude (34) is fixed to the driven scroll (2) by bolts (36).

The drive scroll (1) side is free to slide in the groove (37) provided in the joint (33).

The check valve (39) is pressed against the oil absorption pipe (38) by the leaf spring (48). (41) and (42) are oil passages, which are sealed from the atmospheric pressure chamber (10) by an O-ring (40) and seals (14) and (15). (43) is oil, (44) is a horizontal vent communicating with the oil passage (41) and the outside of the upper container (9), (45) is a vertical vent communicating with this vent (44), ( Reference numeral 46) is a sealing material that seals the external opening of the vent hole (44), and (47) is an opening / closing screw screwed into the upper end opening of the vent hole (45).

The operation of the pump of the above embodiment is as follows. When the motor (27) is rotated, the drive scroll (1) is centered on the shaft.
It is rotated about O ₁ and the driven scroll (2) is rotated following the center O ₂ of the shaft. At that time, the joint (33) and the sleeve (34) provided on the drive scroll (1)
The two scrolls are rotated exactly 180 degrees in a twisted position so that the spiral protrusions (1a) and (2a) are all in contact with each other so that there is no clearance, and the compression chamber (3) is completely closed. It is sealed to improve the degree of vacuum.

By the rotation of both scrolls (1) and (2), suction, compression and discharge of gas are performed as in the case of FIG. By the rotation of the scrolls (1) and (2), the suction port (12)
The gas in the body to be evacuated (not shown) is sucked from the suction chamber, sucked by the suction chamber (6a), and enters the compression chamber (3). In this way, the compression chamber (3) moves to the center side and the gas is compressed. The compressed gas is discharged from the discharge port (1c) to the valve (3
2) is pushed up and reaches the atmospheric pressure chamber (10) through the discharge hole (4b). Then, it is discharged from the exhaust port (11) to the outside atmosphere. The seals (14) and (15) seal the atmospheric pressure chamber (10) and the suction chamber (6a). Valve (32) is compression chamber (3)
The gas compressed and discharged from the inside is prevented from returning from the atmospheric pressure chamber (10). Next, the check valve (39) is opened by the leaf spring (48) by the centrifugal force generated by the rotating force of the motor (27), and the oil (() is transferred to the compression chamber (3) via the oil passages (41) and (42). 43) to supply. Further, when the motor (27) is stopped, the check valve (39) is closed and comes into close contact with the oil absorption pipe (38), and the oil passage (41) is closed. The oil (43) supplied to the compression chamber exerts a sealing function, prevents atmospheric air from entering, and improves the degree of vacuum.

In the above description, the case where the check valve (39) is opened by the leaf spring (48) has been described. However, for example, a cam (not shown) is driven according to the rotation of the rotating shaft (29), and this cam The check valve (39) may be opened / closed by using a solenoid valve, or a solenoid valve may be used to electrically open / close the same effect.

By the way, in the above embodiment, the vertical type is shown. However, in the case of the horizontal type, the check valve (39) is placed under the exhaust port (1
This can be achieved by setting 1) above. In other words, it can be used as a vertical or horizontal type, and the range of applications will be expanded.

The oil passage (41) and the oil passage (42) communicate with a common space between the bearing (17) and the seal (14), and the oil is temporarily stored in the space. Oil is surely supplied from the space at any angle when the (42) rotates, and on the other hand, the bearing (17) is surely lubricated.

On the other hand, as shown in Fig. 2, the ultimate vacuum P _{1 is} reached at time t ₁ .
In the state of reaching, the presence of a gas that is easily liquefied in the gas to be evacuated, since it is operated in a high compression ratio state, for example, water vapor will be generated in the gas, The degree of vacuum tends to deteriorate as indicated by the broken line in FIG.

However, in this state, open the open / close screw (47),
When the atmosphere is introduced into the compression chamber (3) through the vents (45) (44) and the oil passages (41) (42), the valve (32) is opened by the introduced atmosphere and before the high compression ratio is achieved. In compression chamber (3)
The gas inside is discharged and the liquefaction of the gas inside the compression chamber (3) is prevented.

By the way, in the above-mentioned embodiment, the description has been given of the case where the air passages (41) and (42) are communicated with the ventilation ports (44) and (45), but the compression chamber (3) is provided separately from the oil passages (41) and (42). A passage may be formed communicating with the driven scroll (2).
It may be formed on the side.

Moreover, although the opening and closing screw (47) is provided as the opening and closing member in the above description, an electromagnetic valve may be provided.

〔The invention's effect〕

As described above, the present invention is directed to the first container having the intake port,
A second container that is airtightly coupled to the first container and has an exhaust port and is filled with oil, is rotatably disposed in the first container, and has a substantially axial center that communicates with the second container. A first scroll having a discharge port for rotating, a second scroll that cooperates with the first scroll to form a compression chamber, and one of the first scroll and the second scroll is rotationally driven. The drive chamber, the check valve that reversely stops the flow path of the discharge port, the first container or the second container, and the first scroll are pierced through the compression chamber to the first chamber.
A vent that can communicate with the outside of the container or the second container,
And since it is equipped on the outside opening side of this vent and has an opening / closing member capable of opening and closing the vent, it is possible not only to prevent the gas from liquefying in the compression chamber, but also to liquefy the gas. It can be reliably discharged, and a high degree of vacuum can be obtained over a long period of time.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of a scroll vacuum pump according to the present invention, FIG. 2 is a characteristic diagram showing the degree of vacuum thereof, and FIG.
(A)-(d) is an operation principle figure of the scroll fluid machine of the whole system rotation type. In the figure, (1) is a drive scroll, (1a) is a spiral protrusion,
(1c) is a discharge port, (2) is a driven scroll, (2a) is a spiral protrusion, (3) is a compression chamber, (4) is a drive shaft, (4a) is an exhaust path, (4b) is a discharge port, (6) is a container, (7) is a bearing housing, (8) is an upper container, (10) is an atmospheric pressure chamber,
(11) is the exhaust port, (12) is the intake port, (27) is the motor,
(29) is a rotating shaft, (32) is a valve, (38) is an oil absorption pipe, (39)
Is a check valve, (40) is an O-ring, (41) is an oil passage, (42)
Is an oil passage, (43) is oil, (44) (45) is a vent, (47)
Is an open / close screw. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A first container having an intake port, a second container airtightly coupled to the first container, having a discharge port and containing oil, and rotatably arranged in the first container. A first scroll having a discharge port that communicates with the second container approximately at the center, a second scroll that cooperates with the first scroll to form a compression chamber, and the first scroll. A drive source that rotationally drives one of the second scrolls, a check valve that reversely stops the flow path of the discharge port, the first container or the second container, and the first scroll. A vent for penetrating the compression chamber to communicate the compression chamber with the outside of the first container or the second container, and an opening / closing member that is attached to the outside opening side of the vent to open and close the vent. Equipped scroll fluid machine.