KR102008939B1

KR102008939B1 - Scroll compressor with a seal for a back pressure chamber

Info

Publication number: KR102008939B1
Application number: KR1020140084486A
Authority: KR
Inventors: 박일영
Original assignee: 한온시스템 주식회사
Priority date: 2014-07-07
Filing date: 2014-07-07
Publication date: 2019-08-08
Also published as: KR20160005499A

Abstract

The present invention relates to a scroll compressor, according to one aspect of the invention, the casing; A fixed scroll provided in the casing; A pivoting scroll which pivots with respect to the fixed scroll and has an insertion groove formed on a rear surface thereof; A main frame supporting the pivoting scroll; A hollow rotating shaft coupled to the swing scroll to eccentrically rotate the swing scroll; And a sealing chamber provided between the main frame and the pivoting scroll to form a back pressure chamber and inserted into the insertion groove, wherein the sealing chamber has at least two surfaces exposed to the back pressure chamber side. A scroll compressor is provided.

Description

SCROLL COMPRESSOR WITH A SEAL FOR A BACK PRESSURE CHAMBER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor, and more particularly, to a scroll compressor having a sealing chamber for sealing a back pressure chamber for pressurizing a swing scroll to a fixed scroll side.

The scroll compressor is a compressor using a fixed scroll having a spiral wrap and a rotating scroll pivoting about the fixed scroll, wherein the volume of the compression chamber formed between the fixed scroll and the rotating scroll interlocks according to the pivoting motion of the rotating scroll. It is reduced, thereby increasing the pressure of the fluid is a compressor of the type that is discharged from the discharge port opening in the center of the fixed scroll.

Such a scroll compressor has a feature that suction, compression, and discharge are continuously performed while the swing scroll is turning. Therefore, there is no need of a discharge valve and a suction valve, and in principle, the number of parts is simple, and the structure is simple, and high speed rotation is achieved. Possible features In addition, there is a small fluctuation in torque required for compression, and since suction and compression occur continuously, noise and vibration are small.

1 is a cross-sectional view showing a part of a conventional scroll compressor. Referring to FIG. 1, a fixed scroll 10 and a rotating scroll 12 engaged to pivot in a lower portion of the fixed scroll 10 include an ejection opening 14 at an approximately center portion of the fixed scroll 10. Formed. The discharge port 14 is provided with a discharge valve assembly 16 for preventing the discharged compressed refrigerant from flowing backward. The space located above the discharge port forms a high pressure space in which the compressed high pressure gas temporarily stays. In order to minimize the occurrence of pulsation caused by the discharge gas, a partition 18 is formed in the high pressure space.

Meanwhile, in the scroll compressor of the type described above, it is necessary to prevent leakage between the fixed wrap and the swing wrap provided in the fixed scroll and the swing scroll during the operation. In order to prevent leakage, the fixed wrap and the swiveling wrap should be strongly in contact with each other.

In order to solve this problem, a back pressure chamber is formed on the back of the swing scroll, and a part of the working fluid under compression is supplied into the back pressure chamber to prevent leakage between the swing scroll and the fixed scroll by pressure balance. Since the back pressure chamber is disposed between the swinging scroll and the main frame, the back pressure chamber is provided with a sealing chamber so that the working fluid inside the back pressure chamber does not leak. In the case of the conventional sealing chamber, there is a problem in that leakage occurs due to insufficient sealing performance.

The present invention has been made to overcome the disadvantages of the prior art as described above, it is another technical problem to provide a scroll compressor having a sealing chamber for the back pressure chamber that can provide a superior sealing performance compared to the prior art.

According to an aspect of the present invention for achieving the above technical problem, a casing; A fixed scroll provided in the casing; A pivoting scroll which pivots with respect to the fixed scroll and has an insertion groove formed on a rear surface thereof; A main frame supporting the pivoting scroll; A hollow rotating shaft coupled to the swing scroll to eccentrically rotate the swing scroll; And a sealing chamber provided between the main frame and the pivoting scroll to form a back pressure chamber and inserted into the insertion groove, wherein the sealing chamber has at least two surfaces exposed to the back pressure chamber side. A scroll compressor is provided.

Here, the sealing chamber includes a first side surface extending outwardly from the main frame and an inclined surface connected to the first side surface and inclinedly extending from the first side surface, wherein a vertical component of pressure applied to the inclined surface is the main frame. It may be arranged to face.

Here, the insertion groove may be formed such that the inner wall surface is spaced apart from the inclined surface.

The sealing chamber may also include a second side surface extending at least partially parallel to the surface of the main frame.

In addition, the insertion groove may be formed to be spaced apart from the second side.

In addition, the sealing chamber may have a polygonal shape and may have an inclined surface extending between a first side surface orthogonal to the main frame and a second side surface disposed in parallel with the main frame.

According to one aspect of the present invention having the above configuration, since the pressure in the back pressure chamber is applied from at least two side surfaces of the sealing chamber, the sealing chamber can seal the back pressure chamber more stably, thereby further improving the sealing performance. It can be improved.

1 is a cross-sectional view showing a part of a conventional general scroll compressor.
2 is a sectional view showing a first embodiment of a scroll compressor according to the present invention.
FIG. 3 is an enlarged cross-sectional view of a portion of the embodiment shown in FIG. 2.
4 is an enlarged cross-sectional view of a modified example of the embodiment illustrated in FIG. 2.
FIG. 5 is an enlarged cross-sectional view of the sealing chamber part of the embodiment illustrated in FIG. 2.
FIG. 6 is an enlarged cross-sectional view of a modification of the sealing chamber of the embodiment illustrated in FIG. 2.
7 is a sectional view showing a second embodiment of a scroll compressor according to the present invention.

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

Referring to FIG. 2, the embodiment 100 has a form in which the motor head 110, the center head 120, and the fixed scroll head 130 are fastened by bolts 102. Here, a space is formed inside the motor head 110, and the stator 112 is fixed to the inner wall of the motor head 110 by using a method such as shrinking in the space. The stator 112 has a hollow shape, and a rotor and a rotating shaft to be described later are disposed inside. In addition, the stator 112 may be disposed such that the entire outer circumferential portion may contact the inner surface of the motor head 110, but in some cases, only a portion of the outer circumferential portion may be disposed to contact the motor head. At this time, the portion not in contact with the motor head may be spaced apart from the inner wall of the motor head, and may function as a flow path through which the working fluid passes. If the entire outer circumferential portion of the stator is in contact with the motor head, a through hole may be formed in the stator along a direction parallel to the rotation axis to form a flow path.

Inside the motor head 110 a support frame 114 is also formed. The support frame 114 is formed to protrude from the inner surface of the motor head 110, and is arranged to form a space between the inner wall surface of the motor head 110. In addition, the support frame 114 is formed with an internal flow passage 114a for communicating the space with the internal space of the motor head 110, and the internal flow passage forms a part of the discharge flow passage to be described later.

The support frame 114 is also equipped with a bearing 116. The bearing 116 serves to rotatably support one end of the rotating shaft, and a ball bearing is used, but any other type of bearing may be used.

The motor head 110 has a discharge port 118 at a boundary with the center header 120. The discharge port 118 is for discharging the compressed working fluid to the outside of the compressor, is formed to penetrate the side wall of the motor head 110, one side of the center head in Figure 2 is one of the discharge port 118 It is arranged to define the side. However, the discharge port 118 may be formed at any position of the motor head 110 irrespective of the center head.

The rotating shaft 140 supported by the bearing 116 is coupled to the rotor 113 to rotate together in the outer peripheral portion. In addition, the rotation shaft 140 includes a shaft portion 142 coupled to the rotor and a coupling portion 144 coupled to the bush to be described later. The fastening portion 144 is formed to have a larger diameter than the shaft portion, and a space is formed inside. In addition, the shaft portion 142 is formed in a hollow so that the compressed working fluid can flow through the rotating shaft. Hereinafter, a flow path provided inside the rotating shaft is referred to as a first discharge flow path 146.

On the other hand, the other side of the rotary shaft 140, that is, the fastening portion 144 is supported by the center head 120. The center head 120 is formed to have a substantially disk shape, the center portion is formed thicker than the edge. First and second bearings 121 and 122 are mounted at the center of the center head 120, and the first bearing 121 is rotatable to the other end of the rotation shaft, that is, the fastening part 144. Will be supported. In addition, the second bearing 122 rotatably supports the bush 124 fastened through the fastening part 144 and the driving pin 133.

The bush 124 is eccentrically inserted into the boss portion of the swinging scroll to be described later, and is spaced apart from the inner bottom surface of the fastening portion 144. As a result, a space is formed between the fastening part 144 and the bush 124, which is called a buffer space 124a.

The center head 120 includes a ring-shaped flat member 126 and a gasket 128 on an opposite surface of the fixed scroll head 130. The gasket 128 is positioned between the center head and the fixed scroll head to prevent leakage of the working fluid.

The fixed scroll head 130 includes a hard plate 131 and a spiral fixed wrap 132 integrally formed with the hard plate 131. In addition, the rear surface of the hard plate 131 is provided with a storage space 133, the storage space 133 may be sealed by a cover 134. The storage space 133 is utilized as a space for storing the control unit 135 for controlling the rotation of the rotor, the control unit 135 includes an inverter circuit for controlling the power supply required for the rotation of the rotor. can do. Here, in FIG. 2, the storage space is illustrated as being provided in the fixed scroll head, but the present invention is not limited thereto, and an example provided in the motor head side may be considered. In addition, an example in which the storage space is provided in a separate structure separate from the compressor may be considered.

In addition, the fixed scroll head 130 is formed with an inlet 136 through which the working fluid to be compressed is introduced, and the working fluid introduced through the inlet 136 is compressed by the fixed scroll and the turning scroll 150. .

Referring to FIG. 3, the pivoting scroll 150 includes a hard disk portion 151 in the form of a disc and a pivoting wrap 152 engaged with the fixed wrap 132 of the fixed scroll. A compression chamber is defined between the two wraps, and the volume of the compression chamber is gradually reduced as the compression chamber moves to the center of the hard plate part according to the turning motion of the turning scroll. The rear surface of the hard plate 151 is formed to protrude boss portion 153 is fastened to the bush 124 described above. The boss 153 has a short cylindrical shape, and a second discharge passage 153a is formed therein so as to extend through the hard plate.

The second discharge passage 153 together with the above-described first discharge passage 146 forms a discharge passage through which the compressed working fluid is discharged. This will be described later.

Here, although the boss of the revolving scroll is inserted into the bush 124 to fasten the two to each other, the shape is not necessarily limited to this form, and a form in which the bush is inserted into the boss may be considered.

On the other hand, the rotating scroll is provided with a rotation preventing groove 154 and the anti-rotation pin 155 to continue the rotational movement under the driving force of the rotating shaft. The anti-rotation groove 154 is formed on the bottom surface of the hard plate, the anti-rotation pin 155 is inserted into the center head and fixed at one end, and the other end is located inside the anti-rotation groove 154. . Due to the interaction between the anti-rotation groove and the anti-rotation pin, the turning scroll is constrained to rotate without rotating. As the anti-rotation mechanism, a mechanism such as Oldhamling may be used in addition to the pin.

In the operation of the embodiment, that is, when the working fluid is compressed, the hard disk of the swing scroll and the surface of the center head are spaced apart from each other to form the back pressure chamber 156. The back pressure chamber 156 is provided to prevent the leakage of the working fluid through the contact surface of the swing scroll and the fixed scroll, and to reduce wear and power loss due to excessive friction. Specifically, a back pressure passage 153b is formed in the boss portion 153 in communication with the back pressure chamber 156, so that a part of the working fluid discharged is introduced into the back pressure chamber through the back pressure passage 153b, The pivoting scroll is pushed to the fixed scroll side. Here, since the pressure of the back pressure chamber and the pressure between the swing scroll and the fixed scroll are approximately balanced, it is possible to reduce the loss due to excessive friction while preventing the leakage of the working fluid.

Here, the back pressure flow passage has a form of a hole drilled through the boss portion, but is not necessarily limited to this form. That is, as shown in FIG. 4, instead of the boss, a back pressure passage 153b ′ may be formed to penetrate the hard plate of the revolving scroll so as to directly connect the back pressure chamber 156 and the compression chamber. At this time, one or a plurality of the back pressure flow passage may be formed, and the position thereof may be disposed between the outer peripheral portion and the central portion of the hard plate. The closer the back pressure passage is to the outer peripheral portion of the hard plate, the lower the back pressure applied to the back pressure chamber, and the closer to the center, the higher the back pressure. Therefore, those skilled in the art can select an appropriate position in consideration of design specifications and the like.

Since the back pressure flow path can be formed to be short enough to penetrate the boss, the high pressure working fluid inside the compression chamber can be quickly supplied into the back pressure chamber. As a result, back pressure can be quickly supplied into the back pressure chamber in the case of initial start-up, thereby improving response. In addition, since the process for processing the back pressure flow path can be simplified, thus improving productivity.

The back pressure chamber 156 is configured to prevent the fluid inside the back pressure chamber from leaking by the sealing chamber 157. Therefore, when leakage occurs due to insufficient performance of the sealing chamber 157, the pressure in the back pressure chamber is lowered to cause leakage between the turning scroll and the fixed scroll. 3 and 4, the sealing chamber 157 has a rectangular shape, and one side of the sealing chamber 157 is prevented from leaking under pressure of a working fluid inside the back pressure chamber.

Specifically, in FIGS. 3 and 4, the sealing chamber 157 is inserted into and fixed in an insertion groove formed in the hard plate of the revolving scroll, and the back pressure applied from the back pressure chamber is applied only to one side of the lower end of the sealing chamber 157. You lose. As a result, the sealing chamber 157 is deformed to the left side with reference to FIG. 3 and the contact area with the main frame is reduced or the gap is opened. For this reason, there exists a possibility that sealing performance may fall.

Therefore, in order to further improve the leakage preventing performance, it is necessary to increase the contact pressure between the contact surface between the bottom surface 157a of the sealing chamber and the surface of the center head. That is, when the bottom surface 157a of the sealing chamber presses the surface of the center head more strongly, the sealing performance can be further improved.

Accordingly, as shown in FIGS. 2 and 5, the inclined surface 157b may be disposed on the sealing chamber 157. That is, due to the inclined surface, the surface exposed to the back pressure chamber is extended to two. In addition, the seal insertion groove 158 into which the sealing chamber 157 is inserted is configured to be spaced apart from the inclined surface 157b. For this reason, the pressure inside the back pressure chamber is applied to both the side surface and the inclined surface 157b of the sealing chamber. The side pressure acts to press the sealing chamber 157 to the left side with reference to FIG. 5 to prevent leakage between the sealing chamber and the turning scroll, and the vertical component of the pressure acting on the inclined surface is the bottom surface of the sealing chamber ( Since 157a is pressed toward the center head side, leakage between the sealing chamber and the center head can be prevented. In addition, the horizontal component of the pressure is to press the side of the sealing chamber toward the side of the turning scroll further increases the sealing performance.

As a result, the leakage blocking performance can be further improved as compared with the rectangular sealed chambers shown in FIGS. 3 and 4. Here, the gap between the seal insertion groove 158 and the sealing chamber is shown to be exaggerated than actual for the sake of understanding, and at any interval that allows the pressure inside the back pressure chamber to act on the inclined surface. Of course, can be spaced apart.

In order to further double the leakage blocking performance, the sealing chamber may be modified in the form shown in FIG. In FIG. 6, the sealing chamber has a substantially pentagonal shape and is connected to the inclined surface to form an upper surface 157c. The upper surface is also spaced apart from the insertion groove to further double the force for pressing the sealing chamber in the vertical direction. That is, by arranging the upper surface 157c of the sealing chamber adjacent to the inclined surface 157b to be spaced apart from the thread insertion groove 158, the pressure acting on the bottom surface of the sealing chamber can be further increased. In this case, a total of three surfaces are exposed to the back pressure chamber side.

The operation of the first embodiment shown in FIG. 2 will now be described.

In FIG. 2, the working fluid introduced through the inlet 136 is compressed between the swing scroll and the fixed scroll, and moves to the center of the swing scroll. The compressed fluid thus moved is discharged out of the compression chamber through the second discharge passage 153a, and then flows into the first discharge passage 146 via a buffer space 124a formed between the bush and the fastening portion. do.

By providing a buffer space between the first discharge passage and the second discharge passage, the compressed working fluid can flow smoothly even if the two passages are shifted from each other. In other words, the buffer space functions as a kind of buffer. Of course, in some cases, an example in which the buffer space is omitted may be considered.

The compressed fluid moved along the first discharge passage 146 is discharged into the space provided in the support frame 114 and then flows into the space inside the motor head via the internal flow passage 114a. Therefore, the internal space of the first embodiment may be divided into a high pressure space in which a high pressure compressed fluid exists and a low pressure space in which suction is performed based on the center head. The compressed fluid present in the high pressure space is then discharged to the outside of the compressor via the discharge port 118.

Since the compressed working fluid is not immediately discharged to the outside, but is discharged after staying in the high pressure space, the partition structure for pulsation reduction as in the prior art is unnecessary. In addition, since the existing high pressure space is utilized as a space for pulsation reduction, the volume and weight of the compressor can be reduced as compared with the conventional art.

Meanwhile, in the above embodiment, the motor head, the center head, and the fixed scroll head are configured to be combined with each other to form an appearance.

FIG. 7 is a diagram corresponding to FIG. 2 showing a second embodiment 200 of the scroll compressor according to the present invention. The same components as those shown in FIG. 2 are denoted by the same reference numerals, and description thereof will not be repeated. It was.

Since the internal structure of the second embodiment shown in FIG. 7 is the same as the first embodiment shown in FIG. 2, the differences will be mainly described. Referring to FIG. 7, a flow path is configured such that the working fluid discharged through the first discharge flow path is discharged through a bearing, not an internal flow path formed in the support frame. According to this configuration, since the cooling and lubrication of the bearing is made more smoothly by the working fluid, it is possible to contribute to improving the bearing performance and life.

In addition, the whole is housed in one casing 210. Here, the casing 210 has a form in which the motor head, the center head, and the fixed scroll head in the first embodiment are integrated. An accommodating space is provided for one control unit, and the accommodating space is covered by a cover 134.

Claims

Casing;
A fixed scroll provided in the casing;
A pivoting scroll which pivots with respect to the fixed scroll and has an insertion groove formed on a rear surface thereof;
A main frame supporting the pivoting scroll;
A hollow rotating shaft coupled to the swing scroll to eccentrically rotate the swing scroll; And
And a sealing chamber provided between the main frame and the pivoting scroll to form a back pressure chamber and inserted into the insertion groove.
The sealing chamber has at least two surfaces exposed to the back pressure chamber side,
The sealing chamber includes a first side surface extending outwardly from the main frame and an inclined surface connected to the first side surface and inclinedly extending from the first side surface,
And a vertical component of pressure applied to the inclined surface is directed toward the main frame.

delete

The method of claim 1,
And the insertion groove is formed such that an inner wall thereof is spaced apart from the inclined surface.

Casing;
A fixed scroll provided in the casing;
A pivoting scroll which pivots with respect to the fixed scroll and has an insertion groove formed on a rear surface thereof;
A main frame supporting the pivoting scroll;
A hollow rotating shaft coupled to the swing scroll to eccentrically rotate the swing scroll; And
And a sealing chamber provided between the main frame and the pivoting scroll to form a back pressure chamber and inserted into the insertion groove.
The sealing chamber has at least two surfaces exposed to the back pressure chamber side,
And the seal chamber includes a second side surface extending at least partially parallel to the surface of the main frame.

The method of claim 4, wherein
The insertion groove is a scroll compressor, characterized in that formed to be spaced apart from the second side.

Casing;
A fixed scroll provided in the casing;
A pivoting scroll which pivots with respect to the fixed scroll and has an insertion groove formed on a rear surface thereof;
A main frame supporting the pivoting scroll;
A hollow rotating shaft coupled to the swing scroll to eccentrically rotate the swing scroll; And
And a sealing chamber provided between the main frame and the pivoting scroll to form a back pressure chamber and inserted into the insertion groove.
The sealing chamber has at least two surfaces exposed to the back pressure chamber side,
And the sealing chamber has a polygonal shape and has an inclined surface extending between a first side surface orthogonal to the main frame and a second side surface disposed parallel to the main frame.