JPS6248980A - Scroll type compressor - Google Patents

Abstract

PURPOSE:To prevent the leakage of a gas introduced into a high pressure chamber and improve refrigerating capacity by slidably sealing a part between the back of a rotating scroll and the high pressure chamber of a high pressure receiving ring by means of a sealing member. CONSTITUTION:A high pressure ring 9 is provided opposite to the discharge opening 11a of a discharge gas passage 11, on the back of a rotating scroll 2. A double cylinder type seal ring 20 is slidably provided in the high pressure chamber 10 of the high pressure ring 9, and seal members 22, 23 such as an O-ring are provided between the seal ring 20 and the inner peripheral surface of the high pressure chamber 10, to prevent a gas from leaking. The seal ring 20 is pressed against the back side of the rotating scroll 2 by means of an elastic member 24, to be in close contact with the rotating scroll 2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a scroll compressor, and particularly to a scroll compressor in which the area around a high pressure chamber formed on the back side of an orbiting scroll is improved.

[Technical background of the invention and its problems]

Scroll compressors are known to be constructed by combining a fixed scroll and an orbiting scroll, and have excellent advantages such as small rotational torque fluctuations and high rotation speed, and have recently been used in refrigeration cycles. Such a scroll compressor rotates a fixed scroll 1 and an orbiting scroll 2 by 180 degrees, each having wraps la and 2a formed in a spiral shape such as an involute curve, as shown in FIGS. 5 and 6. The wraps la and 2a form a crescent-shaped compression chamber 3, and the center 02 of the orbiting scroll 2 is aligned with the center 0 of the fixed scroll l.
The refrigerant gas in the compression chamber 3 is compressed in a spiral shape by rotating the compressor 3 while maintaining a constant eccentric distance e from the compression chamber 3.

Then, as shown in FIG. 7, the orbiting scroll 2
In addition to being rotatably provided at the end of a crank 4 connected to an electric motor section (not shown), the outer circumferential portion of the fixed scroll 1 is fixed to a frame 5 disposed around the orbiting scroll 2 to constitute a compression element. ing. Note that 6 is a suction port provided on the outer peripheral side of the fixed scroll 1, 7 is a discharge port provided at the center of the fixed scroll 1, and 8 is an Oldham joint for preventing the orbiting scroll 2 from rotating.

By the way, in such scroll type compressors, the fixed scroll 1 and the orbiting scroll 2 have always been kept in close contact using compressed high-pressure refrigerant gas (discharge gas) to prevent the gas in the process of compression from leaking between the wraps. It is being done to Specifically, conventionally, as shown in FIG. 7, a high pressure receiving ring 9 is provided concentrically on the back side of the orbiting scroll 2, and a high pressure receiving ring 9 is provided along the circumferential direction on the surface of the high pressure receiving ring 9 facing the orbiting scroll 2. In addition to forming a high-pressure chamber 10 in the rotating spacer 2, a discharge gas passage 11 that communicates the high-pressure chamber 10 with the discharge side of the compression chamber 3 is formed in the end plate of the rotating spacer 2. The orbiting scroll 2 is moved toward the fixed scroll 1 by introduction into the chamber 10, the thrust load is reduced, and the orbiting scroll 2 and the fixed scroll 1 are prevented from being separated. Although not shown, in addition to this, a high pressure chamber 10 may be provided in the frame 5, or a high pressure chamber 10 may be provided in the end plate of the orbiting scroll 2, and the high pressure receiving ring 9 may be provided with a high pressure chamber 10.
There are also models that receive thrust loads without using a thrust load, but the effect is the same.

However, although this structure for introducing compressed gas into the high pressure chamber 10 certainly allows the fixed scroll 1 and the orbiting scroll 2 to be brought into close contact with each other during operation, on the other hand, the orbiting scroll 2 is brought into close contact with the fixed scroll due to the introduction of the compressed gas. 1 side, a gap is created between the high pressure chamber 10 and the back surface of the orbiting scroll 2, and there is a problem in that the compressed gas introduced into the high pressure chamber 10 leaks from the gap. especially,
Since the leaked gas leaks into the suction atmosphere, the refrigeration capacity is reduced accordingly, and the high temperature causes the temperature of nearby sliding parts to rise unnecessarily.

[Purpose of the invention]

The present invention was made in view of these problems, and its purpose is to provide a scroll compressor that can prevent leakage from the high pressure chamber.

[Summary of the invention]

This invention includes a seal ring that is movably inserted into a high pressure chamber along the axial direction of an orbiting scroll and is displaced by receiving gas introduced into the high pressure chamber to seal the back surface of the orbiting scroll. By interposing a sealing member that slidably seals the circumferential surface of the orbiting scroll and the circumferential surface of the opposing high pressure chamber, the seal ring seals the back surface of the orbiting scroll, and the sealing member seals the high pressure chamber. The purpose is to seal the chamber and minimize leakage of gas introduced into the high-pressure chamber.

[Embodiments of the invention]

The present invention will be explained below based on one embodiment not shown in FIGS. 1 to 3. FIG. 1 shows the compression elements of a scroll compressor. In addition, in Figure 1, the 7th section of the conventional section
Components that are the same as those of the compression element shown in the figures are given the same reference numerals, and their explanations are omitted.Here, we will explain the parts that are different, that is, the structure around the high pressure chamber, which is the main part of this invention. do.

That is, 20 is a seal ring made of, for example, tetrafluoroethylene resin, cast iron, or the like. Seal ring 20
is formed into a cylindrical shape that can be fitted into the high pressure chamber 10, and
A ring-shaped through hole 21 extending along the axial direction is formed in the center of the peripheral wall portion to form a substantially double cylinder structure. The seal ring 20 is fitted into the high pressure chamber 10 so as to be movable in the vertical direction (the axial direction of the orbiting scroll 2), and a through hole 21 communicating with the high pressure chamber 10 is opened on the back surface of the orbiting scroll 2. It faces the discharge port 11a of the discharge gas passage 11. In other words, compressed gas can be introduced into the high-pressure chamber 10 through the through hole 21 (one structure is used).

Further, the seal ring 10 is configured to move (displace) in the vertical direction following the vertical movement of the orbiting scroll 2 by introducing compressed gas, and thereby move the upper end surface of the seal ring 20 to the orbiting scroll. 2, so that the orbiting scroll 2 side can be sealed.

Further, on the inner and outer circumferential surfaces of the seal ring 20, O-rings 2 are provided, respectively, located at portions that always face the inner circumferential surface of the high pressure chamber 10.
2.23 (corresponding to the seal member of the present invention) is provided. Each of these O-rings 22 and 23 connects the high pressure chamber 1.
0 and the outer circumferential surface of the seal ring 20, and together with the surface seal on the back surface of the orbiting scroll 2, leakage of the compressed gas introduced into the high pressure chamber 10 is prevented. I'm trying to make it possible. In addition, 22a.

Reference numeral 23a indicates an O-ring mounting groove formed on the inner and outer circumferential surfaces of the seal ring 20. Further, an elastic member is provided between the inner bottom surface of the high pressure chamber 10 and the end surface of the seal ring 20 facing thereto.
For example, a high pressure chamber as shown in Fig. 2 (a) and (b)]0
A plate spring 24 is inserted in which a part of the plate surface of a ring-shaped elastic plate 24a that can be inserted into the interior is cut and raised in an abbreviated shape, and the elastic force of the cut and raised pieces 24b... is used to form a seal ring. 20 is pressed (energized) against the back surface of the orbiting scroll 2, the surface pressure of the sealing surface 25 between the orbiting scroll 2 and the seal ring 10 is increased. Further, the end portion of the seal ring 20 installed in the high pressure chamber 10 that seals the orbiting scroll 2 is formed in a flange shape, and the width dimension of the sealing surface 25 is set to the orbiting radius of the orbiting scroll 2, that is, the eccentric distance e. The oil film required for sealing can always be ensured in the region where r, &-e>OJ.

Note that 20b indicates a flange portion in which the width of the sealing surface 25 is increased.

Thus, in such a scroll compressor, by operating an electric motor section (not shown), its rotational force is transmitted to the orbiting scroll 2 through the crankshaft 4, and the orbiting scroll 2 is driven to orbit. The rotation of the orbiting scroll 2 changes the compression chamber 3 formed between the wraps la and 2a, and sucks the refrigerant gas from the suction port 6.
Compress the inhaled gas. A cycle is formed in which compressed gas is discharged from the discharge lower, thereby compressing the refrigerant.

During this compression process, a part of the compressed gas flows into the high pressure chamber 10 of the high pressure receiving ring 9 from the discharge port 1ia of the discharge gas passage 11. Then, the pressure of the inflowing discharge gas lifts the orbiting scroll 2 toward the fixed scroll, reducing the thrust load and maintaining the state in which the fixed scroll 1 and the orbiting scroll 2 are in close contact with each other.
Here, it is pointed out that conventionally, gas introduced into the high pressure chamber 10 leaks to the surroundings through a gap created between the high pressure receiving ring 9 and the orbiting scroll 2.

However, according to the present invention, this can be improved. That is, the seal ring 20 receives the pressure of the discharge gas flowing into the high pressure chamber 3, and the orbiting scroll 2
It moves (displaces) in the vertical direction following the movement of , and its tip surface comes into close contact with the back surface of the orbiting scroll 2 . Thereby, the seal ring 20 forms a face seal while sliding on the orbiting scroll 2. At the same time, the seal ring 20
The sliding surfaces between the high-pressure chamber 10 and the high-pressure chamber 10 are sealed with O-rings 22 and 23 attached to the inner and outer peripheral surfaces of the seal ring 20. Therefore, the space between the high pressure chamber 10 and the orbiting scroll 2 is sealed, and leakage of the discharge gas introduced into the high pressure chamber 10 is reduced.

As a result, it is possible to improve the refrigerating capacity.

Moreover, since leakage is prevented, unnecessary temperature increases in nearby sliding parts are prevented, resulting in the effect of improving the reliability of the compressor.

Furthermore, since the seal ring 20 can move up and down, it will not move with the downward movement of the orbiting scroll 2 even when the pressure inside the compression chamber 3 is abnormally high or when the wraps la and 2a are thermally expanded. However, there is an advantage in being able to tolerate them.

In addition, the width dimension of the sealing surface 25 of the seal ring 20 relative to the orbiting scroll 2 is made larger than the eccentric distance e, and the leaf spring 24 moves the seal ring 20 to the orbiting scroll 2.
There is an advantage that leakage between the back surface of the orbiting scroll 2 and the seal ring 20 can be significantly prevented by biasing the rotor to the side. That is, regarding the former, when the width dimension of the seal surface 25 is smaller than the eccentric distance e, the oil film required for the seal is actually damaged by the sliding contact of the orbiting scroll 2 and cannot be maintained.

However, by making the width dimension of the sealing surface 25 larger than the eccentric distance e, the sliding surface (
A region that always retains an oil film is formed within the seal width. Therefore, leaks due to poor oil film retention can be prevented and leaks can be significantly reduced. According to experiments, the refrigerating capacity of the compressor was investigated by changing the seal width dimension, and as shown in FIG. It was confirmed that it is possible to prevent losses.

You will continue to see a significant reduction in leaks. In addition, the latter technique of urging the seal ring 20 toward the orbiting scroll 2 using the leaf spring 24 increases the surface pressure of the sealing surface 25 by pressing the seal ring 20 against the orbiting scroll 2, thereby preventing leakage from the high pressure chamber 10. is decreasing. Of course, the same effect can be achieved by using not only the leaf spring 24 but also other elastic members such as coil springs. The synergy of these effects effectively reduces the leakage of discharged gas.

Furthermore, the present invention is not limited to the above-mentioned embodiment, and other embodiments shown in FIG. 4 may be used. That is, the one shown in FIG. 4 does not use an elastic member, but is placed in close contact with the back surface of the orbiting scroll 2, and O-rings 22 and 23 are provided on the inner peripheral surface of the high-pressure receiving ring 9.

The present invention may also be applied to a scroll type compressor in which a high pressure chamber is formed in the end plate of an orbiting scroll to receive a thrust load without using a high pressure receiving ring.

Further, in the above-described embodiment, a seal ring in which the inner and outer peripheral parts are integrated is used, but a seal ring in which the inner and outer peripheral parts are separated may be used.

〔Effect of the invention〕

As explained above, according to the present invention, the back surface of the orbiting scroll is sealed with the seal ring, and the high pressure chamber can be slidably sealed with the seal member, thereby minimizing the leakage of gas introduced into the high pressure chamber. It can be reduced.

Therefore, leakage from the high pressure chamber can be prevented, and the refrigerating capacity can be improved.

Moreover, since leakage is prevented, unnecessary temperature rises in nearby sliding parts are prevented, which has the effect of improving the reliability of the compressor.

[Brief explanation of the drawing]

Figures 1 to 3 show one embodiment of the present invention.
The figure is a front sectional view showing a scroll compressor, Figure 2 (a)
is a plan view showing the elastic member that biases the seal ring;
Figure (b) is its front view, Figure 3 is a diagram showing that the loss of refrigerating capacity decreases as the seal 1m between the seal ring and the orbiting scroll becomes larger than the eccentric distance, and Figure 4 is a diagram showing this. A front sectional view showing a main part of another embodiment of the invention, FIGS. 5 and 6 are diagrams for explaining the relationship between a fixed scroll and an orbiting scroll, and FIG. 7 shows a conventional scroll compressor FIG. 1...Fixed scroll, 2...Orbiting scroll, 2
0... Seal ring, 22. 23... 0 ring (sealing member), 24... Leaf spring (elastic member), 25...
・Seal surface, e... Eccentric distance.

Claims (3)

[Claims] (1) In a scroll compressor which is provided with a fixed scroll and an orbiting scroll that meshes with the fixed scroll, and a ring-shaped high pressure chamber for receiving compressed gas is formed on the back side of the orbiting scroll, in the axial direction of the orbiting scroll. A seal ring is movably inserted into the high pressure chamber along the periphery of the seal ring and seals the back surface of the orbiting scroll by being displaced by receiving the gas introduced into the high pressure chamber. A scroll compressor characterized in that a sealing member is interposed between the inner circumferential surface of a chamber and a sealing member that slidably seals the two. (2) The scroll compressor according to claim 1, wherein the width of the sealing surface of the seal ring that seals the back surface of the orbiting scroll is greater than the eccentric distance of the orbiting scroll. (3) The scroll compressor according to claim 1, wherein the seal ring is biased toward the orbiting scroll by an elastic member.