KR102033109B1

KR102033109B1 - Scroll compressor

Info

Publication number: KR102033109B1
Application number: KR1020130057317A
Authority: KR
Inventors: 김학영; 이강욱; 김철환
Original assignee: 엘지전자 주식회사
Priority date: 2013-05-21
Filing date: 2013-05-21
Publication date: 2019-10-16
Also published as: KR20140136796A

Abstract

In the scroll compressor according to the present invention, since a sealing portion is provided at a bearing surface between a rotating shaft engaging portion of a turning scroll and a fixed scroll corresponding thereto, the refrigerant leaks from the compression chamber to the bearing hole in the low pressure type or in the high pressure type. The inflow of the refrigerant from the borehole into the compression chamber can be blocked to improve the compression efficiency of the compressor.

Description

Scroll Compressor {SCROLL COMPRESSOR}

The present invention relates to a scroll compressor, and more particularly, to a scroll compressor for installing a sealing member around the final compression chamber.

The scroll compressor draws and compresses refrigerant by forming a compression chamber in which the rotating scroll continuously moves between the fixed wrap and the rotating wrap while the fixed scroll of the fixed scroll and the rotating wrap of the rotating scroll engage with the fixed scroll. It is a type of compressor.

Such a scroll compressor has a superior advantage over other types of compressors in terms of vibration and noise generated during operation since suction, compression, and discharge are continuously performed.

The behavior of the scroll compressor is determined by the shape of the fixed wrap and the swing wrap. The stationary wrap and the swiveling wrap may have any shape, but typically have the form of an involute curve that is easy to machine. An involute curve is a curve that corresponds to the trajectory that the end of the yarn draws when unwinding the yarn wound around a base circle of any radius. In the case of using the involute curve, the thickness of the lap is constant and the volume change rate is also constant. Therefore, in order to obtain a high compression ratio, the number of turns of the lap needs to be increased, but the size of the compressor also increases.

On the other hand, the turning scroll is typically formed on the one side of the disk plate in the form of a turning wrap, the boss portion is formed on the back surface is not formed the turning wrap is connected to the rotating shaft for rotating the turning scroll. This type can form a turning wrap over almost the entire surface of the hard plate, so that the diameter of the hard plate part can be reduced to obtain the same compression ratio, while the reaction force to counteract the action point to which the refrigerant repulsive force is applied during compression and the repulsive force is applied. There is a problem in that the operating point is spaced apart in the vertical direction and the vibration of the swing scroll becomes unstable in the operation process, the vibration or noise increases.

As a method for solving this problem, a so-called through-through scroll compressor is disclosed in which the point where the rotating shaft 1 and the turning scroll 2 are coupled to each other is formed on the same surface as the turning wrap 2a as shown in FIG. Such a shaft-through scroll compressor can solve the problem that the swing scroll (2) is inclined because the action point of the reaction force of the refrigerant and the action point of the reaction force act on the same point.

However, in the conventional shaft-through scroll compressor as described above, as shown in Fig. 2, the rotating shaft 1 penetrating through the bearing hole 3b of the fixed scroll 3 is connected to the rotating shaft engaging portion 2b of the turning scroll 2. As it is coupled between the compression chamber (S1) (S2) of the high pressure portion and the bearing hole (3b) of the fixed scroll (3) of the low pressure portion is located close to, thereby part of the refrigerant compressed in the compression chamber (S1) (S2) There is a problem that the compressor efficiency is greatly lowered due to leakage between the rotary shaft engaging portion (2b) of the rotating scroll (2) and the hard plate portion (3c) of the fixed scroll (3). In particular, when the shaft-through scroll compressor is installed in an air conditioner, when the cooling operation requires less cooling power than the heating operation, the lap expansion is relatively small, so that the gap between the fixed scroll 3 and the turning scroll 2 is further reduced. As it opens up, refrigerant leakage can increase.

It is an object of the present invention to provide a scroll compressor which can reduce leakage of refrigerant between the compression chamber and the borehole.

In order to achieve the object of the present invention, a sealed container; A fixed scroll which is fixedly installed in the sealed container, a bearing hole is formed, and a fixed wrap is formed around the bearing hole; A turning scroll having a turning wrap engaged with the fixed wrap to form first and second compression chambers on outer and inner surfaces thereof, the rotating shaft engaging portion being formed at the center thereof to pivot with respect to the fixed scroll; A rotating shaft having an eccentric portion at one end thereof and coupled to a rotating shaft engaging portion of the pivoting scroll through the anchoring hole of the fixed scroll so that the eccentric portion is laterally overlapped with the pivoting wrap; And a driving unit for driving the rotating shaft, and a scroll compressor having a sealing portion installed on a bearing surface between the rotating shaft engaging portion of the swing scroll and a fixed scroll corresponding thereto.

In the scroll compressor according to the present invention, since the sealing member is provided on the bottom surface of the rotating shaft coupling portion positioned between the compression chamber and the bearing hole, the compressor may be blocked to leak the refrigerant into the bearing hole, thereby improving the compression efficiency of the compressor.

1 is a longitudinal sectional view showing a compression portion of a conventional shaft-through scroll compressor;
FIG. 2 is a vertical cross-sectional view showing part “A” in the shaft-through scroll compressor according to FIG. 1 and showing refrigerant leakage in a compression chamber during a cooling operation; FIG.
3 is a longitudinal sectional view showing a shaft through scroll compressor according to the present invention;
4 is a plan view showing a compression unit in the shaft-through scroll compressor according to FIG.
FIG. 5 is a longitudinal sectional view showing part “B” in the shaft-through scroll compressor according to FIG. 3; FIG.
6 is a perspective view of the rotating scroll and the sealing member separated from the compression unit according to FIG.
7 is a longitudinal sectional view showing a state in which a compression chamber and a bearing hole are sealed in the compression unit according to FIG. 5;
8 is a longitudinal sectional view showing another example of the sealing member in the shaft-through scroll compressor according to FIG.
9 is a graph showing a comparison of changes in volumetric efficiency with or without a sealing member in the shaft-through scroll compressor according to FIG.

Hereinafter, the scroll compressor according to the present invention will be described in detail with reference to the embodiment shown in the accompanying drawings.

Figure 3 is a longitudinal sectional view showing a shaft through scroll compressor according to the present invention, Figure 4 is a plan view showing a compression unit in the shaft through scroll compressor according to Figure 3, Figure 5 is a part "B" in the shaft through scroll compressor according to Figure 3 6 is a perspective view showing the rotating scroll and the sealing member separated from the compression unit according to FIG. 5, and FIG. 7 shows a state in which the compression chamber and the bearing hole are sealed in the compression unit according to FIG. Longitudinal section.

As shown in the scroll compressor according to the present embodiment, the drive motor 30 is installed inside the sealed container 10, and the fixed scroll 30 is integral with the main frame on the upper side of the drive motor 20. Is fixedly installed, the rotating scroll 40 is installed on the upper side of the fixed scroll (30) to engage the fixed scroll 30 and coupled to the rotary shaft 23 of the drive motor 20 to compress the refrigerant while the rotating motion. Can be.

The airtight container 10 may be formed of a cylindrical casing 11 and an upper shell 12 and a lower shell 13 which are welded to cover the upper and lower portions of the casing 11, respectively. The suction pipe 14 may be installed on the side of the casing 10, and the discharge pipe 15 may be installed on the upper shell 12. The lower shell 13 also functions as an oil chamber for storing oil supplied so that the compressor can operate smoothly.

The drive motor 20 may include a stator 22 fixed to the inner surface of the casing 10, and a rotor 22 positioned inside the stator 22 and rotated by interaction with the stator 22. have. In the center of the rotor 22, a rotating shaft 23 that rotates with the rotor 22 may be coupled.

An oil passage F is formed in the center of the rotating shaft 23 along the longitudinal direction of the rotating shaft 23, and an oil for supplying the oil stored in the lower shell 13 to the upper end of the rotating shaft 23. Pump 24 may be installed. The pin portion 23c may be eccentrically formed at the upper end of the rotation shaft 23.

The fixed scroll 30 has its outer circumferential surface press-fitted between the casing 11 and the upper shell 12 in a shrink fit manner, or may be joined by welding together with the casing 11 and the upper shell 12.

In addition, a boss portion 32 may be formed in the center of the hard plate portion 31 of the fixed scroll 30, and the bearing portion 33 may be formed in the boss portion 32 so that the rotation shaft 23 passes therethrough. The upper surface of the hard plate portion 31 of the fixed scroll 30 is engaged with the turning wrap 42 to be described later, the first compression chamber (S1) on the outer surface of the turning wrap 42, the second compression chamber ( The fixing wrap 34 forming S2) may be formed.

The revolving scroll 40 may be supported on the top surface of the fixed scroll 30. Swivel scroll 40 has a circular plate portion 41 is formed in a substantially circular shape, two pairs of compression chambers (S1) (S2) continuously engaged with the fixed wrap 34 on the upper surface of the hard plate portion (41) (S2) The pivot wrap 42 may be formed to form. In addition, a substantially circular rotary shaft coupling part 43 may be formed at a central portion of the hard plate part 41 to which the pin part 23c of the rotary shaft 23 is rotatably inserted and coupled.

The pin portion 23c of the rotary shaft 23 is inserted into the rotary shaft coupling portion 43 through the hard plate portion 31 of the fixed scroll 30, and the turning wrap 42, the fixed wrap 34, and the pin portion 23c are inserted into the rotary shaft coupling portion 43. May be installed to overlap the radial direction of the compressor. Here, in the compression, the repulsive force of the refrigerant is applied to the fixed wrap 34 and the turning wrap 42, and a compression force is applied between the rotary shaft coupling portion 43 and the pin portion 23c as a reaction force thereto. As described above, when the pin portion 23c of the rotating shaft 23 penetrates through the light plate portion 41 of the turning scroll 40 and overlaps with the wrap in the radial direction, the repulsive force and the compressive force of the refrigerant are based on the light plate portion 41. Are added to the same side and can be offset against each other.

On the other hand, the fixed wrap 34 and the swing wrap 42 may be formed in an involute curve, but in some cases may be formed to have a curve other than the involute curve. Referring to FIG. 4, when the center of the rotating shaft coupling portion 43 is referred to as O, and the two contact points are called P1 and P2, respectively, the two contact points P1 and P2 are connected to the center O of the rotating shaft coupling portion. It can be seen that the angle α defined by the two straight lines is smaller than 360 ° and the distance l between the normal vectors at each contact point is also larger than zero. Accordingly, the compression ratio can be increased since the first compression chamber S1 immediately before the discharge has a smaller volume than the case where the fixed wrap 34 and the turning wrap 42 formed of the involute curve are provided.

In addition, a protruding portion 35 protruding toward the rotation shaft coupling portion 43 is formed near the inner end of the fixed wrap 34, and a protruding portion 35 has a contact portion 35a protruding from the protruding portion 35. Can be further formed. Accordingly, the inner end of the fixing wrap may be formed to have a larger thickness than other portions.

The rotary shaft coupling portion 43 may be formed with a recess 44 to be engaged with the protrusion 35. One side wall of the concave portion 44 may be in contact with the contact portion 35a of the protrusion 35 to form one side contact point P1 of the first compression chamber S1.

In the drawings, reference numeral 50 denotes an old dam ring, and 60 denotes an upper frame.

In the scroll compressor according to the present embodiment as described above, when the rotating shaft 23 rotates by applying power to the driving motor 20, the turning scroll 40 eccentrically coupled to the rotating shaft 23 rotates along a constant trajectory. After the movement, the compression chambers S1 and S2 formed between the turning scroll 40 and the fixed scroll 30 continuously move toward the center of the turning movement, so that the volume decreases to continuously discharge the refrigerant while continuously compressing the refrigerant. You will repeat a series of steps.

Here, the bottom surface of the revolving scroll 40, that is, the bottom surface 43a around the rotary shaft coupling portion 43 and the bearing surface B of the upper surface of the hard plate portion 31 of the fixed scroll 30 are in contact with each other to form the first compression chamber ( S1) and the second compression chamber S2 are sealed. However, the first compression chamber (S1) and the second compression chamber (S2) is not only to form a high pressure as the volume narrows toward the inside, in the case of the first compression chamber (S1), the protrusion of the fixed wrap 34 As the volume narrows more rapidly in the concave portion 44 of the 35 and the turning wrap 42, the pressure in the compression chamber suddenly rises.

Accordingly, in the case of the shaft-through scroll compressor, the bearing hole 33 having a relatively low pressure is disposed in proximity to the first compression chamber S1 and the second compression chamber S2, and thus the first compression chamber S1 and the first compression chamber S1. A part of the refrigerant compressed in the second compression chamber S2 may leak into the bearing hole 33 due to the pressure difference. However, when the sealing portion 100 is formed between the compression chambers S1 and S2 and the bearing hole 33 as in the present embodiment, the refrigerant in the high pressure compression chambers S1 and S2 has a low pressure. Leakage into the hole 33 can be effectively blocked.

5 and 6, the sealing groove 110 having an annular shape on the bottom surface of the rotary shaft coupling portion 43, that is, the bearing surface, is formed around the rotary shaft coupling portion 43 to surround the rotary shaft coupling portion 43. Is formed, the sealing groove 110 may be inserted into the sealing member 120 also annular.

The sealing member 120 may be formed in the form of a cross-section of the plug having one side open and the other side blocked as shown in FIG. 7. In this case, the sealing member 120 is formed in an annular shape that forms an inner surface such that the closed surface faces the compression hole 33 while the opened surface forms an outer surface toward the compression chambers S1 and S2. As the opening surface of the sealing member 120 is opened by the refrigerant to be leaked from the compression chambers S1 and S2, the sealing force may be further increased, which may be preferable.

Meanwhile, the sealing member 120 may be formed in a simple shape such as a square cross section or a circular cross section as shown in FIG. 8. Even in this case, while the refrigerant to be leaked from the high pressure compression chamber (S1) (S2) flows into the sealing groove (110), while the sealing member 120 is in close contact with the inner surface of the sealing groove (110) bearing of the fixed scroll (30) The surface B may be in close contact with each other to prevent the refrigerant from leaking.

FIG. 9 is a graph showing changes in volumetric efficiency depending on the presence or absence of a sealing member in the shaft-through scroll compressor according to FIG. 3. As shown in the figure, when the sealing part is installed between the compression chamber and the bearing hole, it can be seen that the volumetric efficiency of about 1 to 3% is improved in each of the experimental examples.

In this way, a portion of the refrigerant compressed in the compression chamber gradually moves inward toward the turning side discharge port to be compressed and leak into the relatively low pressure bearing hole, but the sealing member is disposed on the bottom surface of the rotating shaft coupling portion located between the compression chamber and the bearing hole. As it is provided, it is possible to block the refrigerant to be leaked from the compression chamber to the bearing hole to prevent the compression efficiency from being lowered. In particular, when the axial-through scroll compressor is installed in the air-conditioning and air conditioner, during the cooling operation with low cooling power requirement, the lap expansion is small, and the refrigerant leakage may increase as the gap between the rotating shaft coupling portion of the swing scroll and the hard plate portion of the fixed scroll increases. Even in this case, the sealing member blocks the gap between the turning scroll and the fixed scroll, thereby significantly reducing the refrigerant leakage.

Meanwhile, in the above-described embodiment, the low pressure compressor in which the inner space of the sealed container forms the low pressure part has been described, but the same may be applied to the high pressure compressor in which the inner space of the sealed container forms the high pressure part. Since the basic configuration and operation and effect of the present embodiment are similar to those of the above-described embodiment, a detailed description thereof will be omitted.

In this case, however, it may be preferable to arrange the opening surface of the sealing member so as to face the bearing hole, which is a high pressure part, to increase the sealing effect.

30: fixed scroll 33: bearing hole
34: fixed wrap 40: turning scroll
42: turning wrap 43: rotating shaft coupling portion
43a: bottom surface of the rotating shaft coupling portion 100: sealing portion
110: sealing groove 120: sealing member

Claims

Airtight containers;
A fixed scroll which is fixedly installed in the sealed container, a bearing hole is formed, and a fixed wrap is formed around the bearing hole;
A turning scroll which is engaged with the fixed wrap to form first and second compression chambers on outer and inner surfaces thereof, and has a rotating shaft coupling portion formed in the center thereof to pivot about the fixed scroll;
An upper frame provided on an opposite side of the fixed scroll about the pivoting scroll to support the rear surface of the pivoting scroll in an axial direction;
A rotating shaft having an eccentric portion at one end thereof and coupled to a rotating shaft engaging portion of the pivoting scroll through the anchoring hole of the fixed scroll so that the eccentric portion is laterally overlapped with the pivoting wrap; And
And a drive unit for driving the rotating shaft.
A sealing part is installed on the bearing surface between the rotating shaft coupling portion of the swing scroll and the corresponding fixed scroll.
The bearing surface of the rotary shaft coupling portion is formed with an annular sealing groove to surround the rotary shaft coupling portion,
An annular sealing member is inserted into and coupled to the sealing groove,
The sealing member is a scroll compressor having a cross-sectional shape in which one side of the transverse direction is opened and the other side is blocked and opened on one side, and the open side of the sealing member is installed toward the high pressure side.

delete

The method of claim 1,
The inner space of the sealed container is divided into a low pressure part and a high pressure part by the fixed scroll,
The drive unit is a scroll compressor installed in the low pressure portion.