JP2009085027A - 2-stage compression rotary compressor - Google Patents

Abstract

To obtain a two-stage compression rotary compressor excellent in compression efficiency.
A low-stage side compressor and a high-stage compressor are connected to a suction side of a low-stage compressor, and a low-pressure refrigerant is sucked into a cylindrical sealed container arranged vertically. Connected to the discharge side of the low-stage side compression pipe, the low-stage side discharge pipe that discharges the low-stage discharge refrigerant out of the sealed container, and connected to the suction side of the high-stage compression section A high-stage suction pipe for sucking the refrigerant discharged from the stage, a low-pressure connection pipe for connecting the low-stage suction pipe and the accumulator and introducing the refrigerant in the accumulator to the suction side of the low-stage compression section, and the low-stage side An intermediate connecting pipe connecting the discharge pipe and the high-stage suction pipe, and the inner diameter of the low-pressure connecting pipe is larger than the inner diameter of the intermediate connecting pipe.
[Selection] Figure 1-1

Description

  The present invention relates to a two-stage compression rotary compressor.

  In general, a two-stage compression rotary compressor is composed of a low-stage compression section and a high-stage compression section, a motor for driving the low-stage compression section and the high-stage compression section, and a compressor body side. An accumulator is provided on the side.

  The hermetic container has a first through hole, a second through hole, and a third through hole arranged in a line along the longitudinal direction of the rotation shaft, and is connected to the suction side of the low-stage compression section through the second through hole. Thus, a low-stage suction pipe for sucking the low-pressure refrigerant Ps is provided.

  In addition, a low-stage discharge pipe is connected to the discharge side of the low-stage compression section through the first through hole and discharges the low-stage discharge refrigerant Pm once out of the sealed container, and a high through the third through-hole. A high-stage suction pipe that sucks the low-stage discharge refrigerant Pm is connected to the suction side of the stage-side compression section.

  Here, the lower stage suction pipe and the lower end surface of the accumulator are connected by a low pressure connecting pipe, and the lower stage discharge pipe and the higher stage suction pipe are connected by an intermediate connecting pipe.

  Therefore, the flow of the gas refrigerant is as follows. The low-pressure Ps gas refrigerant sequentially flows down the accumulator, the low-pressure connecting pipe, and the low-stage suction pipe, and is sucked into the low-stage compression portion through the low-stage suction hole and compressed to the intermediate pressure Pm. The intermediate pressure Pm gas refrigerant discharged into the low-stage side discharge space sequentially flows down the low-stage side discharge pipe, the intermediate connecting pipe, and the high-stage side suction pipe, and is sucked into the high-stage side compression portion from the high-stage side suction hole. , Compressed to high pressure Pd. The high-pressure Pd gas refrigerant discharged into the internal space of the sealed container passes through the gap of the motor and is discharged from the discharge pipe to the refrigeration cycle side (see, for example, Patent Document 1).

JP 2006-152931 A

  However, according to the prior art, the inner diameters of the low pressure connecting pipe and the intermediate connecting pipe are the same. And since the suction volume of the low stage side compression part is larger than the suction volume of the high stage side compression part, the circulation volume flow rate is larger in the low pressure communication pipe than in the intermediate communication pipe. Therefore, if the inner diameters of the low-pressure connecting pipe and the intermediate connecting pipe are the same, the low-pressure connecting pipe has a problem that the flow rate is larger and the pressure loss is larger, so that the efficiency is lowered.

  This invention is made | formed in view of the above, Comprising: It aims at obtaining the two-stage compression rotary compressor excellent in compressor efficiency.

  In order to solve the above-described problems and achieve the object, a two-stage compression rotary compressor according to the present invention is a low-stage side in which a cylindrical hermetic container is arranged in a vertical shape and arranged inside the hermetic container. A compression section and a high-stage compression section; a motor for driving the low-stage compression section and the high-stage compression section disposed in the sealed container; and an accumulator disposed on the side of the sealed container; The first through hole, the second through hole, the third through hole, which are sequentially arranged along the longitudinal direction of the sealed container on the side wall of the sealed container, and the low-stage compression unit through the second through hole A low-stage suction pipe that sucks low-pressure refrigerant through the first through-hole and is connected to the discharge side of the low-stage compression section through the first through hole. A low-stage discharge pipe that discharges to the high-pressure side, and the high-stage compression section through the third through hole A high-stage suction pipe that is connected to the suction side and sucks the low-stage-side discharged refrigerant, and a low-stage suction pipe and the accumulator are connected to suck the refrigerant in the accumulator into the low-stage compression section. A two-stage compression rotary compressor comprising: a low-pressure connecting pipe introduced on the side; and an intermediate connecting pipe connecting the low-stage discharge pipe and the high-stage suction pipe, wherein the inner diameter of the low-pressure connecting pipe Is larger than the inner diameter of the intermediate connecting pipe.

  According to the present invention, by making the inner diameter of the low-pressure connecting pipe larger than the inner diameter of the intermediate connecting pipe, there is an effect that the pressure loss in the low-pressure connecting pipe can be reduced and the efficiency can be improved. In particular, when the high-stage cylinder is made thinner than the low-stage cylinder, the low-pressure connection pipe fitted from the side to the low-stage cylinder is changed from the intermediate connection pipe fitted from the side to the high-stage cylinder. Can be made thicker and is effective in reducing pressure loss.

  Embodiments of a two-stage compression rotary compressor according to the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited to the following description, In the range which does not deviate from the summary of this invention, it can change suitably. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

  A first embodiment of the present invention will be described with reference to the compressor cross-sectional view of FIG. 1-1. The compressor 1 is a two-stage compression rotary having a configuration in which a cylindrical hermetic container 10 is disposed vertically and a compression unit 12 and a motor 11 that drives the compression unit 12 are accommodated in the hermetic container 10. It is a compressor.

  The stator 111 of the motor 11 is fixed by being shrink-fitted on the inner peripheral surface of the sealed container 10. The rotor 112 of the motor 11 is disposed in the center of the stator 111 and is fixed by being shrink-fitted to a shaft 15 that mechanically connects the motor 11 and the compression unit 12.

  The compression unit 12 is configured by connecting a low-stage compression unit 12L and a high-stage compression unit 12H located above the low-stage compression unit 12L in series. 1-2 is a figure for demonstrating the main structures of the low stage compression part 12L and the high stage compression part 12H. The low-stage compression unit 12L is configured mainly with a low-stage cylinder 121L. Moreover, the high stage side compression part 12H is comprised mainly by the high stage side cylinder 121H.

  The low-stage cylinder 121L and the high-stage cylinder 121H have cylinder bores (holes) 123L and 123H at positions concentric with the motor 11, respectively. In each of the cylinder bores 123L and 123H, cylindrical pistons 125L and 125H having an outer diameter smaller than the bore diameter are respectively disposed. Thereby, the working space which pumps a refrigerant | coolant is formed between each cylinder 121L, 121H and piston 125L, 125H.

  The two cylinders 121L and 121H have grooves extending from the cylinder bores (holes) 123L and 123H to the entire outside of the cylinder in the same direction, and plate-like vanes 127L and 127H are inserted into the grooves, respectively. Has been. Springs 129L and 129H are inserted between the vanes 127L and 127H and the inner peripheral surface of the sealed container 10, respectively. One end of the vanes 127L and 127H is respectively connected to the pistons 125L and 125H by the elastic force of the springs 129L and 129H. As a result, the working space is partitioned into suction chambers 131L and 131H and compression chambers 133L and 133H, respectively.

  The low stage cylinder 121L and the high stage cylinder 121H are provided with suction holes 135L and 135H communicating with the suction chambers 131L and 131H in order to suck the refrigerant into the suction chambers 131L and 131H, respectively.

  Further, an intermediate partition plate 140 is provided between the low-stage cylinder 121L and the high-stage cylinder 121H. The intermediate partition plate 140 is disposed above the working space of the low-stage cylinder 121L and below the working space of the high-stage cylinder 121H. Blocked. A low-stage end plate 160L is provided below the low-stage cylinder 121L, and closes the lower part of the working space of the low-stage cylinder 121L. Further, a high-stage end plate 160H is provided above the high-stage cylinder 121H, and closes the working space of the high-stage cylinder 121H.

  A lower bearing portion 161L is provided on the lower side of the low-stage end plate 160L, and the lower shaft 151 of the shaft 15 is fitted to the lower bearing portion 161L. Further, an upper bearing portion 161H is provided on the upper side of the high-stage end plate 160H, and the upper shaft 153 of the shaft 15 is fitted to the upper bearing portion 161H.

  The shaft 15 has a low-stage crankshaft 152L and a high-stage crankshaft 152H that are eccentric in directions different by 180 °, and the low-stage crankshaft 152L is engaged with the piston 125L of the low-stage compression section 12L. The high-stage crankshaft 152H is fitted with the piston 125H of the high-stage compression section 12H.

  As the shaft 15 rotates, the pistons 125L and 125H revolve while sliding in contact with the inner walls of the cylinder bores (holes) 123L and 123H, and the vanes 127L and 127H reciprocate along with the revolving movement. The volumes of 131L and 131H and the compression chambers 133L and 133H change continuously. Thereby, the compression unit 12 repeats the suction and compression of the refrigerant.

  A low-stage muffler cover 170L is provided below the low-stage end plate 160L, and a low-stage discharge muffler chamber 180L is formed between the low-stage side end plate 160L. The discharge of the low-stage compression unit 12L opens into the low-stage discharge muffler chamber 180L. That is, the low-stage end plate 160L is provided with a low-stage discharge hole 190L that connects the working space of the low-stage cylinder 121L and the low-stage discharge muffler chamber 180L. Is provided with a low-stage discharge valve 200L that prevents backflow.

  1-3 is a cross-sectional view taken along the line AA in FIG. 1-1 according to the first embodiment of the present invention, and is a view for explaining the configuration of the low-stage end plate 160L of the compressor 1. FIG. 1-4 and FIG. 1-5 are cross-sectional views for explaining the low-stage discharge valve 200L, and are cross-sectional views taken along line BB in FIG. 1-4. As shown in FIGS. 1-3 and 1-4, in the present embodiment, the low-stage discharge muffler chamber 180L is a single space in which the left and right sides are in communication with each other. This is a part of an intermediate communication passage that communicates with the suction side of the stage side compression section 12H.

  Also, as shown in FIGS. 1-4 and 1-5, a discharge valve presser 201L is fixed on the low stage discharge valve 200L by a rivet 203 to limit the operation of the low stage discharge valve 200L. . In addition, a low-stage muffler discharge hole 210L that discharges the refrigerant in the low-stage discharge muffler chamber 180L is provided on the outer peripheral wall portion of the low-stage end plate 160L.

  A high stage side muffler cover 170H is provided above the high stage side end plate 160H, and a high stage side discharge muffler chamber 180H is formed between the high stage side end plate 160H. The high-stage end plate 160H is provided with a high-stage discharge hole 190H that allows the working space of the high-stage cylinder 121H and the high-stage muffler cover 170H to communicate with each other. A high-stage discharge valve 200H is provided to prevent this. Further, a discharge valve presser 201H is also fixed on the high stage discharge valve 200H by a rivet so as to limit the operation of the high stage discharge valve 200H.

  The low stage side cylinder 121L, the low stage side end plate 160L, the low stage side muffler cover 170L, the high stage side cylinder 121H, the high stage side end plate 160H, the high stage side muffler cover 170H, and the intermediate partition plate 140 are bolts ( (Not shown). In the compression part 12 fixed integrally by this bolt, the outer peripheral part of the high-stage end plate 160H is fixed to the sealed container 10 by spot welding, and the compression part 12 is fixed to the sealed container. .

  1-6 is a figure for demonstrating the structure of the airtight container 10 of the compressor 1 concerning Example 1 of this invention. In the sealed container 10, a first through hole 101, a second through hole 102, and a third through hole 103 are arranged in order along the longitudinal direction of the sealed container 10. Further, the first through hole 101, the second through hole 102, and the third through hole 103 are arranged in substantially the same direction when viewed from one of the central axes of the sealed container 10.

  Moreover, FIGS. 1-7 is a side view for demonstrating the external appearance of the compressor 1 concerning Example 1 of this invention. On the side surface of the main body of the compressor 1, an accumulator 25 made of an independent sealed container is fixed by an accumulator 251 and an accumulator band 253. A system connection pipe 255 connected to the refrigeration cycle side is provided at the upper part of the accumulator 25, and one end of the accumulator 25 is extended to the upper part inside the accumulator 25 and the other end is connected to the main body of the compressor 1. A low pressure communication pipe 31 is provided.

  The low-pressure communication pipe 31 for sucking in the low-pressure refrigerant of the cycle is connected to the suction side of the low-stage side compression portion 12L, that is, the low-stage side suction hole 135L via the second through hole 101 and the low-stage side suction pipe 104. is doing. In addition, the low-pressure communication pipe 31 is L-shaped in order to avoid interference with the substantially U-shaped intermediate communication pipe 23 that communicates the discharge side of the low-stage compression section 12L and the suction side of the high-stage compression section 12H. The shape has two parts.

  The discharge side of the low-stage discharge muffler chamber 180L, that is, the low-stage muffler discharge hole 210L is connected to the first through hole 101 and the low-stage side of the intermediate connecting pipe 23 provided in a substantially U shape outside the sealed container 10. Connection is made via the discharge pipe 105. The other end of the intermediate connecting pipe 23 is connected to the suction hole 135H of the high stage side compression portion 12H via the third through hole 103 and the high stage side suction pipe 106. That is, the intermediate communication passage that connects the discharge side of the low-stage compression section 12L and the high-stage compression section 12H has a low-stage discharge muffler chamber 180L, a low-stage muffler discharge hole 210L, an intermediate connection pipe 23, a high-stage It is comprised by the high stage side suction hole 135H of the side compression part 12H.

  Here, in the compressor 1 according to the present embodiment, the inner diameter r31 of the low-pressure communication pipe 31 is configured to be larger than the inner diameter r23 of the intermediate communication pipe 23. Thus, by making the inner diameter r31 of the low pressure communication pipe 31 larger than the inner diameter r23 of the intermediate communication pipe 23, the pressure loss of the gas refrigerant flowing down from the accumulator 25 in the low pressure communication pipe 31 is reduced, and the compression efficiency is improved. Can do.

  The intermediate connecting pipe 23 has a substantially U-shape. For this reason, the intermediate communication pipe 23 is formed by making the intermediate communication pipe 23 thinner by making the inner diameter r23 of the intermediate communication pipe 23 smaller than the inner diameter r31 of the low-pressure communication pipe 31, thereby producing the intermediate communication pipe 23. Work becomes easier.

  The discharge of the high stage side compression unit 12H opens into the high stage side discharge muffler chamber 180H, and the discharge of the high stage side discharge muffler chamber 180H opens into the sealed container 10. A discharge pipe 107 that discharges the refrigerant inside the sealed container 10 to the refrigeration cycle side is connected to the upper part of the sealed container 10.

  In the sealed container 10 of the compressor 1, lubricating oil is sealed up to the height of the high-stage cylinder 121 </ b> H, and is circulated through the compression unit by a blade pump (not shown) provided below the shaft 15, Sealing is performed at the location where pressure is divided by lubrication of sliding parts and minute gaps.

  The flow of the gas refrigerant in the compressor 1 described above is as follows. The low-pressure Ps gas refrigerant sequentially flows down the accumulator 25, the low-pressure communication pipe 31, and the low-stage suction pipe 104, and is sucked into the low-stage compression section 12L from the low-stage suction hole 135L and compressed to the intermediate pressure Pm. . The intermediate-pressure Pm gas refrigerant discharged into the low-stage discharge muffler chamber 180L, which is the low-stage discharge space, sequentially flows down the low-stage discharge pipe 105, the intermediate connecting pipe 23, and the high-stage suction pipe 106. The air is sucked into the high-stage compression portion 12H from the side suction hole 135H and compressed to the high pressure Pd. The high-pressure Pd gas refrigerant discharged into the internal space of the sealed container 10 passes through the gap of the motor 11 and is discharged from the discharge pipe to the refrigeration cycle side.

  As described above, in the compressor 1 according to the first embodiment, the low-pressure communication pipe 31 of the gas refrigerant flowing down from the accumulator 25 is configured by making the inner diameter r31 of the low-pressure communication pipe 31 larger than the inner diameter r23 of the intermediate communication pipe 23. Can reduce pressure loss and improve compression efficiency.

  In particular, in the case where the axial thickness of the low-stage cylinder 121L is thicker than the axial thickness of the high-stage cylinder 121H, an intermediate connecting pipe fitted from the side to the high-stage cylinder 121H in accordance with this. 23, it is easy to increase the thickness of the low-pressure connecting pipe 31 fitted from the side to the low-stage cylinder 121L, which is effective for reducing pressure loss.

  In particular, when the compressor 11 is driven by rotating the motor 11 by inverter control with a variable rotation speed, the pressure loss increases as the rotation speed increases. Therefore, according to the present invention, the internal diameter r31 of the low-pressure connecting pipe 31 is made larger than the internal diameter r23 of the intermediate connecting pipe 23 to reduce the pressure loss in the low-pressure connecting pipe 31 and to improve the compression efficiency. Is also effective in reducing pressure loss.

  Further, by configuring the intermediate connecting pipe 23 to be thin, an operation for producing the intermediate connecting pipe 23 by bending the pipe into a substantially U shape is facilitated.

  As shown in FIG. 2, the present invention sucks refrigerant having a pressure intermediate between the condensing pressure and the evaporating pressure of the refrigeration cycle between the discharge side of the low-stage compression section and the suction side of the high-stage compression section. It is also possible to apply the present invention to a two-stage compression rotary compressor (a two-stage compression rotary compressor that supports injection). The injection-compatible two-stage compression rotary compressor 2 shown in FIG. 2 is provided in the middle of the intermediate connecting pipe 23 between the discharge side of the low-stage side compression unit 12L and the suction side of the high-stage side compression unit 12H. An intermediate pressure suction pipe (injection pipe) 81 that sucks an injection refrigerant having a pressure intermediate between the condensation pressure and the evaporation pressure of the refrigeration cycle in which the stage compression rotary compressor is used is provided. The injection-compatible two-stage compression rotary compressor 2 shown in FIG. 2 has the same configuration as the two-stage compression rotary compressor shown in FIG. 1-1 except that an intermediate pressure suction pipe (injection pipe) 81 is provided.

  Also in the injection-compatible two-stage compression rotary compressor 2 according to the second embodiment, the inner diameter r31 of the low pressure communication pipe 31 is made larger than the inner diameter r23 of the intermediate communication pipe 23, so that the gas refrigerant flowing down from the accumulator 25 can be reduced. The pressure loss in the low-pressure communication pipe 31 can be reduced and the compression efficiency can be improved.

  Also, in the injection-compatible two-stage compression rotary compressor 2 according to the second embodiment, when the axial thickness of the low-stage cylinder 121L is thicker than the axial thickness of the high-stage cylinder 121H, In addition, it is easier to make the low pressure communication pipe 31 fitted from the side to the lower stage cylinder 121L wider than the intermediate connection pipe 23 fitted from the side to the high stage cylinder 121H, which is effective in reducing pressure loss. .

  Also in the injection-compatible two-stage compression rotary compressor 2 according to the second embodiment, when the motor 11 is rotated and the compressor 12 is driven by inverter control with a variable rotation speed, the pressure loss increases as the rotation speed increases. Becomes larger. Therefore, according to the present invention, the internal diameter r31 of the low-pressure connecting pipe 31 is made larger than the internal diameter r23 of the intermediate connecting pipe 23 to reduce the pressure loss in the low-pressure connecting pipe 31 and to improve the compression efficiency. Is also effective in reducing pressure loss.

  Also in the injection-compatible two-stage compression rotary compressor 2 according to the second embodiment, the intermediate connecting pipe 23 is made thin, so that the operation when the intermediate connecting pipe 23 is produced by bending the pipe into a substantially U shape is performed. It becomes easy.

  As the pipes having different diameters, for example, an intermediate connecting pipe is formed inside the compressor, and the diameters of the injection pipe and the low-pressure side suction pipe are different (for example, Japanese Patent Laid-Open No. 2006-2006). No. 152931 (see FIG. 1), the effect according to the present invention cannot be obtained regardless of the improvement of the pressure loss in the low pressure communication pipe.

  As described above, the two-stage compression rotary compressor according to the present invention is useful for efficient compression.

It is sectional drawing for demonstrating the structure of the two-stage compression rotary compressor concerning Example 1 of this invention. It is a figure for demonstrating the main structures of the low stage side compression part and high stage side compression part of the two-stage compression rotary compressor concerning Example 1 of this invention. It is a figure for demonstrating the structure of the low stage side end plate of the two-stage compression rotary compressor concerning Example 1 of this invention, and is a cross-sectional view of a low stage side end plate. It is sectional drawing for demonstrating the low stage side discharge valve of the two-stage compression rotary compressor concerning Example 1 of this invention. It is sectional drawing for demonstrating the low stage side discharge valve of the two-stage compression rotary compressor concerning Example 1 of this invention. It is a figure for demonstrating the structure of the airtight container of the two-stage compression rotary compressor concerning Example 1 of this invention. It is a side view for demonstrating the external appearance of the two-stage compression rotary compressor concerning Example 1 of this invention. It is sectional drawing for demonstrating the structure of the injection | emission 2 step | paragraph compression rotary compressor concerning Example 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 Injection-compatible 2 stage | paragraph compression rotary compressor 10 Airtight container 11 Motor 12 Compression part 12L Low stage side compression part 12H High stage side compression part 15 Shaft 23 Middle connection pipe 25 Accumulator 31 Low pressure connection pipe 101 1st through-hole 102 Second through-hole 103 Third through-hole 104 Low-stage suction pipe 105 Low-stage discharge pipe 106 High-stage suction pipe 107 Discharge pipe 111 Stator 112 Rotor 121L Low-stage cylinder 121H High-stage cylinder 123L, 123H Cylinder bore 125L, 125H Piston 127L, 127H Vane 129L, 129H Spring 131L, 131H Suction chamber 133L, 133H Compression chamber 135L Low stage suction hole 135H High stage suction hole 140 Intermediate partition plate 151 Lower shaft 152L Low stage crankshaft 152H High stage Crankshaft 153 Upper shaft 160L Low stage end plate 160H High stage end plate 161L Lower bearing part 161H Upper bearing part 170L Low stage muffler cover 170H High stage muffler cover 180L Low stage discharge muffler chamber 180H High stage discharge muffler Chamber 190L Low stage discharge hole 190H High stage discharge hole 200L Low stage discharge valve 200H High stage discharge valve 210L Low stage muffler discharge hole 251 Accum holder 253 Accum band 255 System connection pipe

Claims (4)

Cylindrical sealed containers are arranged vertically,
A low-stage compression section and a high-stage compression section disposed inside the sealed container;
A motor for driving the low-stage compression section and the high-stage compression section disposed inside the sealed container;
An accumulator disposed on the side of the sealed container;
A first through hole, a second through hole, a third through hole, which are sequentially arranged along the longitudinal direction of the closed container on the side wall of the closed container;
A low-stage suction pipe that sucks low-pressure refrigerant by connecting to the suction side of the low-stage compression section through the second through hole;
A low-stage discharge pipe connected to the discharge side of the low-stage compression section through the first through hole and discharging low-stage discharge refrigerant out of the sealed container;
A high-stage suction pipe that sucks the low-stage discharge refrigerant through the third through hole and is connected to the suction side of the high-stage compression section;
A low-pressure communication pipe that connects the low-stage suction pipe and the accumulator and introduces the refrigerant in the accumulator to the suction side of the low-stage compression section;
An intermediate connecting pipe connecting the low-stage discharge pipe and the high-stage suction pipe;
A two-stage compression rotary compressor comprising:
The inner diameter of the low-pressure connecting pipe is larger than the inner diameter of the intermediate connecting pipe;
A two-stage compression rotary compressor. The axial thickness of the low-stage cylinder that constitutes a part of the low-stage side compression part and is connected to the low-pressure connecting pipe via the low-stage side suction pipe is a part of the high-stage side compression part. It is configured and thicker than the axial thickness of the high stage side cylinder connected to the intermediate connecting pipe via the high stage side suction pipe,
The two-stage compression rotary compressor according to claim 1. The two-stage compression rotary compressor has a variable speed specification;
The two-stage compression rotary compressor according to claim 1. A refrigerant having a pressure intermediate between the condensation pressure and the evaporation pressure in the refrigeration cycle in which the two-stage compression rotary compressor is used between the discharge side of the low-stage compression section and the suction side of the high-stage compression section Providing means for inhaling
The two-stage compression rotary compressor according to claim 1.

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