CN114810586A - scroll compressor - Google Patents

Abstract

The present application provides a scroll compressor including a first scroll compression mechanism, a second scroll compression mechanism, a drive shaft, and a bushing. The first scroll compression mechanism has a first fixed scroll and a first movable scroll movable relative to the first fixed scroll to compress a working fluid. The second scroll compression mechanism has a second non-orbiting scroll and a second orbiting scroll movable relative to the second non-orbiting scroll to compress a working fluid. The drive shaft includes a first eccentric journal engaged with the first orbiting scroll to enable driving of the first orbiting scroll and a second eccentric journal engaged with the second orbiting scroll to enable driving of the second orbiting scroll. The bushing is disposed between the first orbiting scroll and the first eccentric journal and/or between the second orbiting scroll and the second eccentric journal, and is configured to allow radial separation between the first orbiting scroll and/or between the second orbiting scroll and the second orbiting scroll in certain situations.

Description

scroll compressor

technical field

The present disclosure relates to a scroll compressor, and more particularly, to a scroll compressor with a dual compression mechanism.

Background technique

The content in this section merely provides background information related to the present disclosure and may not constitute prior art.

The scroll compressor may include a first scroll compression mechanism and a second scroll compression mechanism to meet capacity requirements. The first scroll compression mechanism and the second scroll compression mechanism each include a fixed scroll and an orbiting scroll, wherein the orbiting scroll orbits relative to the corresponding fixed scroll to compress the working fluid.

During the operation of the compressor, impurities are inevitably introduced into the compression mechanism, specifically, between the intermeshing wraps of the fixed scroll and the movable scroll. At this time, in order to avoid damage to the wraps, it is desirable that the wraps of the fixed scroll and the movable scroll can be separated from each other. This capability of allowing the wraps of the fixed scroll and the movable scroll to be able to be separated from each other is also referred to as the flexibility capability. For example, a structure that allows the fixed scroll and the movable scroll to be able to be separated from each other in the axial direction is called an axially flexible structure, and a structure that allows the fixed scroll and the movable scroll to be able to be separated from each other in the radial direction is called a radially flexible structure structure.

However, for a compressor with a twin-scroll compression mechanism, the structure design is difficult and complicated, and the size is larger because the motion of the twin-scroll compression mechanism and the stress of each component are complex. In particular, the existing compressors with the double scroll compression mechanism do not have a radially flexible structure and/or an axially flexible structure, or have a very complex axially flexible structure.

In view of the above-mentioned facts, it is desirable in the art to provide a compressor having a twin scroll compression mechanism realizing axial and/or radial flexibility, which compressor has a compact and simple structure.

SUMMARY OF THE INVENTION

A general summary of the invention is provided in this section, rather than a comprehensive disclosure of its full scope or all of its features.

An object of the present disclosure is to provide a compressor having a twin scroll compression mechanism realizing radial flexibility, which improves the reliability of the scroll compressor and has a simple structure.

Another object of the present disclosure is to provide a compressor having a twin scroll compression mechanism realizing axial flexibility, which has a compact and simple structure.

According to one aspect of the present disclosure, there is provided a scroll compressor including a first scroll compression mechanism, a second scroll compression mechanism, a drive shaft, and a bushing. The first scroll compression mechanism has a first fixed scroll and a first orbiting scroll movable relative to the first fixed scroll to compress the working fluid. The second scroll compression mechanism has a second fixed scroll and a second orbiting scroll movable relative to the second fixed scroll to compress the working fluid. The drive shaft includes a first eccentric journal and a second eccentric journal, the first eccentric journal is engaged with the first orbiting scroll to be able to drive the first orbiting scroll, and the second eccentric journal is engaged with the second orbiting scroll to enable The second orbiting scroll is driven. A bushing is arranged between the first orbiting scroll and the first eccentric journal and/or between the second orbiting scroll and the second eccentric journal, and is configured to allow the first fixed scroll to communicate with the first orbiting scroll. Radial separation between the scrolls and/or between the second fixed scroll and the second movable scroll is allowed under certain circumstances.

"Specific conditions" as described herein refers to conditions such as the presence of foreign objects therebetween or the pressure within the compression chamber exceeding a safe threshold that may damage the vanes of the fixed and orbiting scrolls during operation of the scroll compressor. In certain circumstances, it is desirable that the orbiting scroll (vanes) be able to be radially separated relative to the fixed scroll (vanes), thereby allowing foreign matter or high pressure fluid, etc. to escape.

According to the scroll compressor, since the bushing allows radial separation between the fixed scroll and the corresponding movable scroll under certain conditions, that is, provides radial flexibility to the scroll compressor, it is possible to prevent the fixed scroll and the vanes of the movable scroll, thereby improving the reliability of the scroll compressor and having a simple structure.

In some embodiments according to the present disclosure, the bushing includes a cylindrical wall and an inner through hole defined by an inner peripheral surface of the cylindrical wall. The inner through hole is used to receive the first eccentric journal and/or the second eccentric journal. The cylindrical wall has different thicknesses in the circumferential direction to allow the cylindrical wall to rotate in the circumferential direction relative to the drive shaft within a predetermined range to achieve the radial separation.

In some embodiments according to the present disclosure, the outer peripheral surface of the cylindrical wall has a circular cross-section. The inner peripheral surface of the cylindrical wall has a circular cross-section.

In some embodiments according to the present disclosure, the bushing includes a cylindrical wall and an inner through hole defined by an inner peripheral surface of the cylindrical wall. The inner through hole is used to receive the first eccentric journal and/or the second eccentric journal. A drive plane portion is provided on the first eccentric journal and/or the second eccentric journal. A driven plane portion is provided on the inner peripheral surface of the cylindrical wall. The drive plane portion cooperates with the driven plane portion so that the cylindrical wall can slide in a radial direction relative to the drive shaft.

In some embodiments according to the present disclosure, the inner through hole has a D-shaped cross-section.

In some embodiments according to the present disclosure, the first eccentric journal protrudes radially outward from the first side of the drive shaft, and the second eccentric journal protrudes from the drive shaft and the first side of the drive shaft. A second side opposite to one side projects radially outward.

In some embodiments according to the present disclosure, the first orbiting scroll and the second orbiting scroll have the same structure.

In some embodiments according to the present disclosure, the end plate of the first orbiting scroll and the end plate of the second orbiting scroll are disposed adjacent to each other in the axial direction, and the end plate of the first fixed scroll is adjacent to each other in the axial direction. The end plate and the end plate of the second fixed scroll are disposed away from each other in the axial direction.

In some embodiments according to the present disclosure, a back pressure cavity is formed between the end plate of the first orbiting scroll and the end plate of the second orbiting scroll. The pressure of the fluid in the back pressure chamber pushes the first orbiting scroll toward the first fixed scroll and the second orbiting scroll toward the second fixed scroll.

In some embodiments according to the present disclosure, a first sealing member and a second sealing member are provided between the end plate of the first orbiting scroll and the end plate of the second orbiting scroll, and the back pressure chamber Defined between a first seal and a second seal, the first seal located radially outward of the second seal.

In some embodiments according to the present disclosure, a first recess for accommodating the first seal is provided on the end plate of the first orbiting scroll and/or the end plate of the second orbiting scroll a groove and a second groove for accommodating the second seal.

In some embodiments according to the present disclosure, the first scroll compression mechanism and the second scroll compression mechanism are independently controllable. Alternatively, the discharge port of the first scroll compression mechanism communicates with the intake port of the second scroll compression mechanism.

According to another aspect of the present disclosure, there is provided a scroll compressor including a first scroll compression mechanism, a second scroll compression mechanism and a drive shaft. The first scroll compression mechanism has a first fixed scroll and a first orbiting scroll movable relative to the first fixed scroll to compress the working fluid. The second scroll compression mechanism has a second fixed scroll and a second orbiting scroll movable relative to the second fixed scroll to compress the working fluid. The drive shaft includes a first eccentric journal and a second eccentric journal, the first eccentric journal is engaged with the first orbiting scroll to be able to drive the first orbiting scroll, the second eccentric shaft A neck engages the second orbiting scroll to be able to drive the second orbiting scroll. A first sealing member and a second sealing member are provided between the first scroll compression mechanism and the second scroll compression mechanism, and the first sealing member is located radially outside the second sealing member. A back pressure cavity into which fluid pressure is introduced is formed between the first seal and the second seal.

According to the scroll compressor, since the axial flexibility can be provided by the back pressure chamber defined by the first seal and the second seal, the reliability of the scroll compressor is improved, the structure is compact and simple, and it is possible to cut costs.

In some embodiments according to the present disclosure, the end plate of the first orbiting scroll and the end plate of the second orbiting scroll are disposed adjacent to each other in the axial direction, and the end plate of the first fixed scroll is adjacent to each other in the axial direction. The end plate and the end plate of the second fixed scroll are disposed away from each other in the axial direction.

In some embodiments according to the present disclosure, the end plate of the first orbiting scroll and/or the end plate of the second orbiting scroll is formed with a fluid for introducing the fluid in the compression chamber into the back pressure chamber the communication channel.

In some embodiments according to the present disclosure, a first recess for accommodating the first seal is provided on the end plate of the first orbiting scroll and/or the end plate of the second orbiting scroll a groove and a second groove for accommodating the second seal.

In some embodiments according to the present disclosure, the first eccentric journal protrudes radially outward from the first side of the drive shaft, and the second eccentric journal protrudes from the drive shaft and the A second side opposite the first side projects radially outward.

In some embodiments according to the present disclosure, the first orbiting scroll and the second orbiting scroll have the same structure.

In some embodiments according to the present disclosure, the scroll compressor further includes a liner. The bushing is arranged between the first orbiting scroll and the first eccentric journal and/or between the second orbiting scroll and the second eccentric journal. The bushing is configured to allow radial direction between the first fixed scroll and the first orbiting scroll and/or to allow the radial direction between the second fixed scroll and the second orbiting scroll under certain circumstances separation.

In some embodiments according to the present disclosure, the bushing includes a cylindrical wall and an inner through hole defined by an inner peripheral surface of the cylindrical wall. The inner through hole is used to receive the first eccentric journal and/or the second eccentric journal. The cylindrical wall has different thicknesses in the circumferential direction to allow the cylindrical wall to rotate in the circumferential direction relative to the drive shaft within a predetermined range to achieve the radial separation.

In some embodiments according to the present disclosure, the outer peripheral surface of the cylindrical wall has a circular cross-section, and the inner peripheral surface of the cylindrical wall has a circular cross-section.

In some embodiments according to the present disclosure, the bushing includes a cylindrical wall and an inner through hole defined by an inner peripheral surface of the cylindrical wall, the inner through hole for receiving the first eccentric journal and/or the second eccentric journal. A drive plane portion is provided on the first eccentric journal and/or the second eccentric journal. A driven plane portion is provided on the inner peripheral surface of the cylindrical wall. The drive plane portion cooperates with the driven plane portion so that the cylindrical wall can slide in a radial direction relative to the drive shaft.

In some embodiments according to the present disclosure, the inner through hole has a D-shaped cross-section.

In some embodiments according to the present disclosure, the first scroll compression mechanism and the second scroll compression mechanism are independently controllable. Alternatively, the discharge port of the first scroll compression mechanism communicates with the intake port of the second scroll compression mechanism.

Description of drawings

The features and advantages of one or more embodiments of the present invention will become more readily understood from the following description with reference to the accompanying drawings, wherein:

1 is a schematic longitudinal cross-sectional view of a scroll compressor according to an embodiment of the present disclosure;

Fig. 2 is the partial enlarged schematic diagram of the compression mechanism of the scroll compressor of Fig. 1;

Figure 3 is a schematic diagram of a variation of the compression mechanism of Figure 2;

4 is a schematic perspective view of a bushing according to an embodiment of the present disclosure;

5 is a schematic perspective view of a bushing according to another embodiment of the present disclosure;

6A is a schematic perspective view of a drive shaft of the scroll compressor of FIG. 1;

6B is a schematic end view of the drive shaft of FIG. 6A.

Detailed ways

The following descriptions of various embodiments of the present invention are exemplary only, and in no way limit the invention and its application or usage. The same reference numerals are used to denote the same components in the various drawings, and thus the configuration of the same components will not be described repeatedly.

1 is a schematic longitudinal cross-sectional view of a scroll compressor according to an embodiment of the present disclosure; FIG. 2 is a partially enlarged schematic view of a compression mechanism of the scroll compressor of FIG. 1 . The scroll compressor according to the present disclosure will be described below with reference to FIGS. 1 and 2 .

As shown in FIGS. 1 and 2 , the scroll compressor 100 includes a casing 110 , a top cover 112 disposed at one end of the casing 110 , and a bottom cover 114 disposed at the other end of the casing 110 . Housing 110. Top cover 112 and bottom cover 114 constitute the outer casing of scroll compressor 100 and define a closed interior space.

The scroll compressor 100 includes a motor 120 composed of a stator 122 and a rotor 124 . Motor 120 powers the compression mechanism of scroll compressor 100 . The motor 120 may be placed in the inner space of the scroll compressor 100 . The stator 122 may be fixed to the housing 110 , and the rotor 124 may be located radially inward of the stator 122 and rotatable relative to the stator 122 .

The scroll compressor 100 includes a drive shaft 130, which may also be referred to as a rotating shaft or crankshaft. The drive shaft 130 is used to transmit the power of the motor 120 to the compression mechanism of the scroll compressor 100 . The drive shaft 130 is fixedly mounted in the rotor 124 to rotate with the rotor 124 , eg, with an interference fit. In addition, the drive shaft 130 is coupled to the orbiting scroll of the compression mechanism of the scroll compressor 100 in an eccentric driving manner. In the illustrated example, the drive shaft 130 is placed in the interior space of the scroll compressor 100 via bearing housings (eg, upper bearing housings and/or lower bearing housings). However, it should be understood that a portion of the motor 120 and drive shaft 130 may be located outside the casing of the scroll compressor 100 .

The scroll compressor 100 includes a first compression mechanism CM1 and a second compression mechanism CM2. The first compression mechanism CM1 and the second compression mechanism CM2 are accommodated in the inner space of the scroll compressor 100 . A first intake port In1 and a second intake port In2 are provided in the housing 110 . The working fluid (eg, refrigerant) is introduced into the first compression mechanism CM1 through the first intake joint In1 to compress it. The working fluid (eg, refrigerant) is introduced into the second compression mechanism CM2 through the second intake connection In2 to compress it.

The first compression mechanism CM1 and the second compression mechanism CM2 can be individually controlled. The first compression mechanism CM1 and the second compression mechanism CM2 may be coupled together in parallel. The operation (intake and exhaust) of the first compression mechanism CM1 is independent of the operation (intake and exhaust) of the second compression mechanism CM2. For example, the working fluid compressed by the first compression mechanism CM1 is discharged into the inner space from approximately the center thereof. The working fluid compressed by the second compression mechanism CM2 is discharged into the inner space from the approximate center thereof. The compressed gas in the interior space may be exhausted via a discharge fitting (not shown) on the casing of the scroll compressor 100 . A bypass structure may be provided for the first compression mechanism CM1 and/or the second compression mechanism CM2 to adjust the capacity of the scroll compressor 100 .

The first compression mechanism CM1 and the second compression mechanism CM2 may be coupled together in series. For example, the discharge port of the first compression mechanism CM1 communicates with the intake port of the second compression mechanism CM2 via a pipeline. In this way, the working fluid compressed via the first compression mechanism CM1 can be introduced into the suction port of the second compression mechanism CM2 for secondary compression. The working fluid compressed through the second stage may be discharged into the interior space, and then discharged through a discharge connection (not shown) on the casing of the scroll compressor 100 .

The first compression mechanism CM1 includes a first fixed scroll 151 and a first movable scroll 152 . The first fixed scroll 151 includes an end plate 153 and a fixed scroll 155 extending from one side of the end plate 153 . The first orbiting scroll 152 includes an end plate 154 and an orbiting scroll 156 extending from one side of the end plate 154 . The drive shaft 130 has a first eccentric journal 131 that engages with the first orbiting scroll 152 of the first compression mechanism CM1 to drive the first orbiting scroll 152 . When the driving shaft 130 rotates, the first orbiting scroll 152 orbits relative to the first fixed scroll 151 to compress the working fluid between the orbiting scroll 156 and the fixed scroll 155 .

The second compression mechanism CM2 includes a second fixed scroll 161 and a second movable scroll 162 . The second fixed scroll 161 includes an end plate 163 and a fixed scroll 165 extending from one side of the end plate 163 . The second orbiting scroll 162 includes an end plate 164 and an orbiting scroll 166 extending from one side of the end plate 164 . The drive shaft 130 has a second eccentric journal 132 that engages with the second orbiting scroll 162 of the second compression mechanism CM2 to drive the second orbiting scroll 162 . When the driving shaft 130 rotates, the second orbiting scroll 162 orbits relative to the second fixed scroll 161 to compress the working fluid between the orbiting scroll 166 and the fixed scroll 165 .

The process of compressing the working fluid by the first compression mechanism CM1 and the second compression mechanism CM2 is similar to that of the existing scroll compression mechanism, so it will not be described in detail here.

In the example shown in FIGS. 1 and 2 , the first orbiting scroll 152 and the second orbiting scroll 162 are located between the first fixed scroll 151 and the second fixed scroll 152 . Specifically, the end plate 154 of the first orbiting scroll 152 faces and is adjacent to the end plate 164 of the second orbiting scroll 162 . The end plate 153 of the first fixed scroll 151 and the end plate 163 of the second fixed scroll 161 are far away from each other and are located on opposite sides of the first orbiting scroll 152 and the second orbiting scroll 162 (the upper side and the second orbiting scroll 162 in the figure). lower side).

A first sealing member 171 and a second sealing member 172 are provided between the end plate 154 of the first orbiting scroll 152 and the end plate 164 of the second orbiting scroll 162 . The first seal 171 is located radially outside the second seal 172 . For example, the first seal 171 and the second seal 172 are O-rings or any other suitable type of seal.

In the example of FIGS. 1 and 2 , the end plate 164 of the second orbiting scroll 162 of the second compression mechanism CM2 is provided with a first annular groove 167 for accommodating the first sealing member 171 and a first annular groove 167 for accommodating the first The second annular groove 168 of the second seal 172 . Accordingly, the first annular groove 167 is located radially outside the second annular groove 168 .

A communication passage 173 is provided in the end plate 164 of the second movable scroll 162 . The communication channel 173 introduces the fluid in one of the compression chambers into the space between the first seal 171 and the second seal 172 . Therefore, the space between the first sealing member 171 and the second sealing member 172 forms the back pressure cavity 170 . The pressure of the fluid in the back pressure chamber 170 pushes the first orbiting scroll 152 toward the first fixed scroll 151 and pushes the second orbiting scroll 162 toward the second fixed scroll 161 .

Due to the fluid pressure in the back pressure chamber 170 , the axial distance between the fixed scroll and the movable scroll of each scroll compression mechanism may vary, thereby providing the scroll compressor 100 with axial flexibility. . The first seal 171, the second seal 172 and the back pressure cavity 170 therebetween constitute an axially flexible structure.

The axially flexible structure as described above allows the end plate 154 of the first orbiting scroll 152 and the end plate 164 of the second orbiting scroll 162 to be as close to each other as possible, so the structure of the entire double compression mechanism is very compact, and the dynamic movement can be improved. Balance problems, you can even omit the balance block. Moreover, only the end plate 164 needs to be processed to form grooves for accommodating the first sealing member 171 and the second sealing member 172, and there is no need to provide additional components to provide axial flexibility, so the number of components can be reduced and the simplification The structure of the scroll compressor 100 can also simplify the processing and assembly process of each component, thereby significantly reducing the cost of the scroll compressor 100 . As described above, the first sealing member 171 and the second sealing member 172 may be, for example, O-rings, thus further reducing the cost of the scroll compressor 100 .

The outer circumference of the first fixed scroll 151 may be provided with a first flange 159 . The outer circumference of the second fixed scroll 161 may be provided with a second flange 169 . The first flange 159 and the second flange 169 may be coupled together by bolts 102 . Optionally, the first fixed scroll 151 and the second fixed scroll 161 can move axially relative to each other by means of the guidance of the bolt 102 . The first flange 159 and the second flange 169 may extend toward each other, thereby facilitating coupling and guiding therebetween.

It should be understood that the axially flexible structures according to the present disclosure are not limited to the specific examples shown in FIGS. 1 and 2 . For example, FIG. 3 is a schematic diagram of a variation of the compression mechanism of FIG. 2 . As shown in FIG. 3 , the scroll compressor 200 includes a first compression mechanism CM1 and a second compression mechanism CM2 like the scroll compressor 100 . The first compression mechanism CM1 includes a first fixed scroll 251 and a first movable scroll 252 . The first fixed scroll 251 includes an end plate 253 and a fixed scroll 255 . The first orbiting scroll 252 includes an end plate 254 and an orbiting scroll 256 . The second compression mechanism CM2 includes a second fixed scroll 261 and a second movable scroll 262 . The second fixed scroll 261 includes an end plate 263 and a fixed scroll 265 . The second orbiting scroll 262 includes an end plate 264 and an orbiting scroll 266 .

The scroll compressor 200 differs from the scroll compressor 100 in the arrangement of the axially flexible structure. Specifically, in the example shown in FIG. 3 , the end plate 254 of the first orbiting scroll 252 of the first compression mechanism CM1 is provided with a first annular groove 257 for accommodating the first seal 271 and a first annular groove 257 for accommodating the first sealing member 271 . The second annular groove 258 of the second seal 272 is placed. The first annular groove 257 is located radially outside the second annular groove 258 . A back pressure cavity 270 is formed between the first sealing member 271 and the second sealing member 272 . The end plate 254 of the first orbiting scroll 252 is provided with a communication passage 273 that communicates the compression chamber to the back pressure chamber 270 .

1 to 3 , a bearing 181 is provided between the first fixed scroll 151 (specifically, the end plate 153 ) and the drive shaft 130 . Similarly, a bearing 184 is provided between the second fixed scroll 161 (specifically, the end plate 163 ) and the drive shaft 130 . The bearing 181 and the bearing 184 may be, for example, a cylindrical-shaped sliding bearing having a constant thickness for relieving the wear caused to the end plates 153 and 163 .

A bearing 182 is provided between the first movable scroll 152 (specifically, the central portion of the movable scroll 156 ) and the drive shaft 130 (specifically, the first eccentric journal 131 ). Similarly, a bearing 183 is provided between the second orbiting scroll 162 (specifically, the central portion of the orbiting scroll 166 ) and the drive shaft 130 (specifically, the second eccentric journal 132 ). Bearings 182 and 183 may be similar to bearings 181 and 182 for relieving wear on the orbiting scrolls 156 and 166 .

A first bushing 191 may be provided between the bearing 182 and the first eccentric journal 131 . The first bushing 191 is configured to allow the first fixed scroll 151 to interact with the first fixed scroll 151 (specifically the fixed scroll 155 ) and the first orbiting scroll 152 (specifically the orbiting scroll 156 ) when impurities exist between the first fixed scroll 151 (specifically, the fixed scroll 155 ) and the first orbiting scroll 152 (specifically, the orbiting scroll 156 ). The first orbiting scrolls 152 are radially separated from each other, thereby preventing them from being overstressed and damaged.

Similarly, a second bushing 192 may be provided between the bearing 183 and the second eccentric journal 132 . The second bushing 192 is configured to allow the second fixed scroll 161 to interact with the second fixed scroll 161 (specifically the fixed scroll 165 ) and the second orbiting scroll 162 (specifically the orbiting scroll 166 ) in the presence of impurities The second orbiting scrolls 162 are radially separated from each other, thereby preventing them from being overstressed and damaged. The first bushing 191 and the second bushing 192 constitute the radially flexible structure of the present disclosure.

The "impurities" mentioned herein refer to substances whose volume is not easily changed when compressed, such as solid or liquid substances.

The first bushing 191 may have the same or different structure as the second bushing 192 , as shown in FIG. 4 or FIG. 5 .

4 is a schematic perspective view of the bushing 10 according to an embodiment of the present disclosure. As shown in FIG. 4 , the bushing 10 includes a cylindrical wall 15 and an inner through hole 13 defined by the inner peripheral surface 12 of the cylindrical wall 15 . The inner through hole 13 is used for receiving the first eccentric journal 131 or the second eccentric journal 132 . The cylindrical wall 15 has a varying thickness in the circumferential direction. In this way, when, for example, impurities are present in the compression mechanism, the cylindrical wall 15 is rotated toward the thinner portion in the circumferential direction when the force on the cylindrical wall 15 exceeds a predetermined value. Since the cylindrical wall 15 is turned to the thinner part, the corresponding part of the orbiting scroll (orbiting scroll 156 or 166 ) can be radially separated from the corresponding part of the fixed scroll (the fixed scroll 155 or 165 ) by This protects the movable and fixed scrolls from damage.

The outer peripheral surface 11 of the cylindrical wall 15 may have a circular cross section to match the orbiting scroll. The contour or size of the inner peripheral surface 12 of the cylindrical wall 15 may be designed to allow the cylindrical wall 15 to rotate within a predetermined range in the circumferential direction when impurities enter the compression mechanism. For example, the inner peripheral surface 12 of the cylindrical wall 15 may have a circular cross-section or an elliptical cross-section.

FIG. 5 is a schematic perspective view of a bushing 20 according to another embodiment of the present disclosure. As shown in FIG. 5 , the bushing 20 includes a cylindrical wall 25 and an inner through hole 23 defined by an inner peripheral surface 22 of the cylindrical wall 25 . The inner through hole 23 is used to receive the first eccentric journal 131 or the second eccentric journal 132 . A plane portion 24 is provided on the inner peripheral surface 22 of the cylindrical wall 25 , and correspondingly, a driving plane portion (not shown) matched with the plane portion 24 is provided on the first eccentric journal 131 or the second eccentric journal 132 . Therefore, the flat portion 24 may also be referred to as a driven flat portion. The driven plane portion 24 cooperates with the drive plane portion so that the cylindrical wall 25 can slide relative to the drive shaft 130 in the radial direction. In this way, when, for example, impurities are present in the compression mechanism, the cylindrical wall 25 may slide toward the drive shaft 130 in the radial direction when the force on the cylindrical wall 25 exceeds a predetermined value. Since the cylindrical wall 25 moves toward the drive shaft 130 in the radial direction, the corresponding portion of the orbiting scroll (the orbiting scroll 156 or 166 ) can be diametrically opposed to the corresponding portion of the fixed scroll (the fixed scroll 155 or 165 ). to separate the movable and fixed scrolls from damage.

The inner through hole 23 may have a substantially D-shaped cross section. Similarly, the first eccentric journal 131 or the second eccentric journal 132 may also have a generally D-shaped cross-section.

6A is a schematic perspective view of a drive shaft of the scroll compressor of FIG. 1 ; FIG. 6B is a schematic end view of the drive shaft of FIG. 6A . The structure of the drive shaft 130 according to an embodiment of the present disclosure will be described below with reference to FIGS. 6A and 6B .

As shown in FIGS. 6A and 6B , the drive shaft 130 includes a main journal 135 engaged with the first fixed scroll 151 and the second fixed scroll 161 , a first eccentric journal 131 engaged with the first orbiting scroll 152 , and a first eccentric journal 131 engaged with the first orbiting scroll 152 . The second eccentric journal 132 to which the second orbiting scroll 162 is engaged.

The main journal 135 has a center axis CA. The first eccentric journal 131 protrudes radially outward (rightward in the drawing) from the first side (right side in the figure, which is also the first side of the drive shaft) of the main journal 135 and has a central axis CA1 . In the illustrated example, since the first eccentric journal 131 protrudes to the right relative to the main journal 135, the central axis CA1 is offset to the right relative to the central axis CA. That is, the first eccentric journals 131 projecting radially outwards form an eccentric structure with respect to the central axis CA (main journal 135 ). The second side (left side in the figure, which is also the second side of the drive shaft) 1312 of the outer circumference of the first eccentric journal 131 may coincide with the left side 1352 of the outer circumference of the main journal 135, as shown in FIG. 6B. That is, the second side 1312 of the outer circumference of the first eccentric journal 131 extends linearly with respect to the left side 1352 of the outer circumference of the main journal 135 . In this way, installation and removal of the bearing or bushing (eg, from above) is facilitated.

The second eccentric journal 132 may have a similar structure to the first eccentric journal 131 , but is offset by 180 degrees in the circumferential direction relative to the first eccentric journal 131 . That is, the second eccentric journal 132 protrudes radially outward (leftward in the drawing) with respect to the second side of the main journal 135 and has a center axis CA2. The center axis CA2 is offset to the left with respect to the center axis CA. The first side 1323 of the outer circumference of the second eccentric journal 132 may coincide with the right side 1353 of the outer circumference of the main journal 135, as shown in Figure 6B. That is, the first side 1323 of the outer periphery of the second eccentric journal 132 extends linearly with respect to the right side 1353 of the outer periphery of the main journal 135 . Again, this facilitates installation and removal of bearings or bushings (eg, from below).

Usually, the inner diameter ID of the bearings 181 and 184 is substantially equal to the outer diameter of the drive shaft 130 (the outer diameter of the main journal 135 ). The outer diameter OD of the first eccentric journal 131 and the second eccentric journal 132 is larger than the inner diameter ID of the bearings 181 and 184 . Referring to the cross-sectional view of FIG. 6B, inner diameter ID=outer diameter OD-2*shaft eccentricity. In the cross-sectional view shown in Figure 6B, the main journal 135 is inscribed with the eccentric journal (the second eccentric journal 132 is clearly shown). In this way, the size of the bearings 181, 184 can be maximized.

Since the first eccentric journal 131 is deflected by 180 degrees relative to the second eccentric journal 132, the dynamic balance can be well improved. Advantageously, the first orbiting scroll 152 and the second orbiting scroll 162 have substantially the same structure and size. In this way, the dynamic balance problem can be basically eliminated.

As shown in FIG. 6B , the first eccentric journal 131 and the second eccentric journal 132 each have a substantially elliptical cross section. It should be understood that the drive shafts of the present disclosure are not limited to the specific examples shown, but may be changed as desired.

Although various embodiments of the present invention have been described in detail herein, it is to be understood that the invention is not limited to the specific embodiments described and illustrated in detail herein, but may be modified by those skilled in the art without departing from the spirit and scope of the present invention. The skilled person implements other variations. For example, the features of the various embodiments may be combined with each other, or a feature (eg, bearings 182 and 183 ) may be omitted, where not contradictory. All such variations fall within the scope of the present invention. Furthermore, all components described herein may be replaced by other technically equivalent components.

Claims (24)

1. A scroll compressor (100) comprising:

a first scroll compression mechanism (CM1) having a first fixed scroll (151) and a first orbiting scroll (152) movable relative to the first fixed scroll to compress a working fluid;

a second scroll compression mechanism (CM2) having a second non-orbiting scroll (161) and a second orbiting scroll (162) movable relative to the second non-orbiting scroll to compress a working fluid;

a drive shaft (130) including a first eccentric journal (131) engaged with the first orbiting scroll to enable driving of the first orbiting scroll and a second eccentric journal (132) engaged with the second orbiting scroll to enable driving of the second orbiting scroll; and

a bushing (191; 192) arranged between the first orbiting scroll and the first eccentric journal and/or between the second orbiting scroll and the second eccentric journal and configured to allow a radial separation between the first orbiting scroll and/or between the second non-orbiting scroll and the second orbiting scroll in certain circumstances.

2. The scroll compressor according to claim 1, wherein the bushing includes a cylindrical wall (15) and an inner through hole (13) defined by an inner peripheral surface (12) of the cylindrical wall,

the inner through-hole is adapted to receive the first eccentric journal and/or the second eccentric journal,

the cylindrical wall has different thicknesses in a circumferential direction to allow the cylindrical wall to rotate in the circumferential direction relative to the drive shaft within a predetermined range to achieve the radial separation.

3. A scroll compressor as claimed in claim 2, wherein the outer peripheral surface (11) of the cylindrical wall has a circular cross-section, and

the inner peripheral surface (12) of the cylindrical wall has a circular cross section.

4. The scroll compressor of claim 1, wherein the bushing includes a cylindrical wall (25) and an inner through-hole (23) defined by an inner circumferential surface (22) of the cylindrical wall,

the inner through-hole is adapted to receive the first eccentric journal and/or the second eccentric journal,

a driving plane part is arranged on the first eccentric shaft neck and/or the second eccentric shaft neck,

a driven flat surface portion (24) is provided on an inner peripheral surface (22) of the cylindrical wall,

the driving planar portion and the driven planar portion cooperate such that the cylindrical wall is slidable in a radial direction with respect to the driving shaft.

5. The scroll compressor of claim 4, wherein said interior throughbore has a generally D-shaped cross-section.

6. The scroll compressor according to any one of claims 1 to 5, wherein said first eccentric journal (131) projects radially outwardly from a first side of said drive shaft, and

the second eccentric journal (132) projects radially outward from a second side of the drive shaft opposite the first side.

7. The scroll compressor of claim 6, wherein said first orbiting scroll and said second orbiting scroll have the same structure.

8. The scroll compressor of claim 6, wherein the end plate (154) of the first orbiting scroll and the end plate (164) of the second orbiting scroll are disposed axially adjacent to each other and

the end plate (153) of the first non-orbiting scroll and the end plate (163) of the second non-orbiting scroll are disposed axially away from each other.

9. The scroll compressor of claim 8, wherein a back pressure cavity (170) is formed between an end plate (154) of said first orbiting scroll and an end plate (164) of said second orbiting scroll,

the pressure of the fluid in the back pressure chamber pushes the first orbiting scroll towards the first non-orbiting scroll and the second orbiting scroll towards the second non-orbiting scroll.

10. The scroll compressor of claim 9, wherein a first seal (171) and a second seal (172) are disposed between the end plate (154) of the first orbiting scroll and the end plate (164) of the second orbiting scroll, the back pressure chamber (170) being defined between the first seal (171) and the second seal (172), the first seal being located radially outward of the second seal.

11. The scroll compressor of claim 10, wherein a first groove for receiving the first seal and a second groove for receiving the second seal are provided on an end plate of the first orbiting scroll and/or an end plate of the second orbiting scroll.

12. The scroll compressor of any one of claims 1 to 5, wherein the first scroll compression mechanism and the second scroll compression mechanism are independently controllable, or

And the exhaust port of the first scroll compression mechanism is communicated to the suction port of the second scroll compression mechanism.

13. A scroll compressor, comprising:

a first scroll compression mechanism having a first fixed scroll and a first orbiting scroll movable relative to the first fixed scroll for compressing a working fluid;

a second scroll compression mechanism having a second non-orbiting scroll and a second orbiting scroll movable relative to the second non-orbiting scroll to compress a working fluid; and

a drive shaft including a first eccentric journal engaged with the first orbiting scroll to enable driving of the first orbiting scroll and a second eccentric journal engaged with the second orbiting scroll to enable driving of the second orbiting scroll,

wherein a first seal and a second seal are provided between the first scroll compression mechanism and the second scroll compression mechanism, the first seal being located radially outward of the second seal, an

A back pressure chamber into which fluid pressure is introduced is formed between the first seal and the second seal.

14. The scroll compressor of claim 13, wherein the end plate of the first orbiting scroll and the end plate of the second orbiting scroll are disposed axially adjacent to each other, and

the end plate of the first fixed scroll and the end plate of the second fixed scroll are disposed axially away from each other.

15. The scroll compressor of claim 14, wherein a communication passage for introducing fluid in a compression chamber into the back pressure chamber is formed in an end plate of the first orbiting scroll and/or an end plate of the second orbiting scroll.

16. The scroll compressor of claim 14, wherein a first groove for receiving the first seal and a second groove for receiving the second seal are provided on an end plate of the first orbiting scroll and/or an end plate of the second orbiting scroll.

17. The scroll compressor of any one of claims 13 to 16, wherein the first eccentric journal projects radially outward from the first side of the drive shaft, and

the second eccentric journal projects radially outward from a second side of the drive shaft opposite the first side.

18. The scroll compressor of claim 17, wherein said first orbiting scroll and said second orbiting scroll have the same structure.

19. The scroll compressor of any one of claims 13 to 16, further comprising a bushing, wherein said bushing is disposed between said first orbiting scroll and said first eccentric journal and/or between said second orbiting scroll and said second eccentric journal and is configured to allow radial separation between said first orbiting scroll and/or between said second non-orbiting scroll and said second orbiting scroll at certain conditions.

20. The scroll compressor of claim 19, wherein said bushing includes a cylindrical wall and an internal through-hole defined by an inner circumferential surface of said cylindrical wall,

the inner through-hole is adapted to receive the first eccentric journal and/or the second eccentric journal,

the cylindrical wall has different thicknesses in a circumferential direction to allow the cylindrical wall to rotate in the circumferential direction relative to the drive shaft within a predetermined range to achieve the radial separation.

21. The scroll compressor of claim 20, wherein an outer peripheral surface of said cylindrical wall has a circular cross-section, and

the inner peripheral surface of the cylindrical wall has a circular cross section.

22. The scroll compressor of claim 20, wherein said bushing includes a cylindrical wall and an interior through bore defined by an inner peripheral surface of said cylindrical wall,

the inner through-hole is adapted to receive the first eccentric journal and/or the second eccentric journal,

a driving plane part is arranged on the first eccentric shaft neck and/or the second eccentric shaft neck,

a driven flat portion is provided on an inner peripheral surface of the cylindrical wall,

the driving planar portion and the driven planar portion cooperate such that the cylindrical wall is slidable in a radial direction with respect to the driving shaft.

23. The scroll compressor of claim 22, wherein said interior through bore has a D-shaped cross-section.

24. The scroll compressor of any one of claims 13 to 16, wherein the first scroll compression mechanism and the second scroll compression mechanism are independently controllable, or

And the exhaust port of the first scroll compression mechanism is communicated to the suction port of the second scroll compression mechanism.

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