JP2018136086A - refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress noise in a lower frequency band in a refrigerator including a compressor, a condenser, an expander, an evaporator and a refrigerating cycle having a pipe for sequentially connecting them. SOLUTION: A refrigerating cycle having a compressor, a condenser, an expander, an evaporator and a pipe 12 connecting these sequentially, and an annular cavity 16 provided on the outer peripheral side of the pipe 12 and surrounding the pipe 12 are formed. Provided is a refrigerator including a cavity forming portion 14 to be formed and a single communicating portion 23 for communicating the space in the pipe 12 with the cavity 16. [Selection diagram] Fig. 3

Description

  The present invention relates to a refrigerator.

  The refrigerator is a heat source device that is widely used in applications such as factory air conditioning having a clean room such as an electrical and electronic related factory, and district heating and cooling. As the refrigerator, a unit is known in which components such as a centrifugal compressor, a condenser, and an evaporator are arranged in the vicinity to be integrated (see, for example, Patent Document 1).

JP 2002-327700 A

  As the efficiency of refrigerators increases, the increase in noise generated from refrigerators has become an issue. The causes of noise generated from the refrigerator are roughly classified into two types: noise caused by mechanical causes and noise caused by fluid causes.

  Among noises caused by fluid, for example, noises caused by unstable phenomena such as surging and turning stall are noises generated in a low frequency band. It is known that such noise resonates with acoustic impedance of piping inside the refrigerator and the sound is amplified. Therefore, it is effective to reduce the excitation force before the acoustic impedance of the pipe and the noise resonate with each other, and noise countermeasures near the sound source are effective.

  The present invention provides a refrigerator capable of suppressing noise in a low frequency band in a refrigerator including a compressor, a condenser, an expander, an evaporator, and a refrigeration cycle having pipes that sequentially connect these. With the goal.

  According to the first aspect of the present invention, the refrigerator is provided on the outer peripheral side of the compressor, the condenser, the expander, the evaporator, and the refrigeration cycle having a pipe that sequentially connects these, A cavity forming section that forms an annular cavity surrounding the pipe; and a single communication section that communicates the space in the pipe with the cavity.

According to such a configuration, noise generated from at least one of the compressor, condenser, expander, and evaporator constituting the refrigerator resonates with the resonance space of the other component via the pipe. Noise can be reduced before doing so.
In addition, a cavity forming part that forms an annular cavity surrounding the pipe is provided on the outer periphery of the pipe, and the space in the pipe and the cavity communicate with each other through a single communication part, so that sound can be generated in a larger resonance space. Can be reduced. That is, it is possible to obtain a sound absorption characteristic that enables reduction of noise in a lower frequency band.

  The said refrigerator WHEREIN: The said cavity formation part is provided with two or more so that it may adjoin to the radial direction of the said piping, You may provide the single cavity side communication part which connects the cavity adjacent to the said radial direction.

  According to such a configuration, the sound absorption performance can be improved without increasing the size of the cavity forming portion in the axial direction.

  The said refrigerator WHEREIN: The said cavity formation part may be provided with two or more so that it may adjoin to the axial direction of the said piping.

  According to such a configuration, the sound absorption performance can be improved without increasing the radial size of the cavity forming portion.

According to the present invention, before the noise generated from at least one of the compressor, condenser, expander, and evaporator constituting the refrigerator resonates with the resonance space of the other component via the pipe. In addition, noise can be reduced.
In addition, a cavity forming part that forms an annular cavity surrounding the pipe is provided on the outer periphery of the pipe, and the space in the pipe and the cavity communicate with each other through a single communication part, so that sound can be generated in a larger resonance space. Can be reduced. That is, it is possible to obtain a sound absorption characteristic that enables reduction of noise in a lower frequency band.

It is a schematic block diagram of the refrigerator of embodiment of this invention. It is a schematic block diagram of the compressor of the refrigerator of embodiment of this invention, a condenser, and piping which connects these. It is a partial cross section perspective view of the acoustic device of the refrigerator of the embodiment of the present invention. It is sectional drawing of the acoustic device of the refrigerator of embodiment of this invention. It is a graph explaining the sound absorption performance of the acoustic device of the refrigerator of embodiment of this invention. It is sectional drawing of the acoustic device of the 1st modification of embodiment of this invention. It is a perspective view of the acoustic device of the 2nd modification of embodiment of this invention.

Hereinafter, a refrigerator 1 according to an embodiment of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the refrigerator 1 of the present embodiment includes a compressor 2 that compresses a refrigerant W, a condenser 3 that condenses the refrigerant W compressed by the compressor 2 with cooling water, and a condenser 3. A first expansion valve 4 that is an expander that depressurizes the refrigerant W, and an economizer 6 (gas-liquid separator) that separates the refrigerant W from the first expansion valve 4 into a gas-liquid two-phase.

  The refrigerator 1 also includes an inflow path 8 that allows the gas phase W1 from the economizer 6 to flow into the compressor 2, a second expansion valve 5 that depressurizes the liquid phase from the economizer 6, and a second expansion. And an evaporator 7 for evaporating the refrigerant W from the valve 5.

  A hot gas bypass pipe 9 is provided between the vapor phase portion of the condenser 3 and the vapor phase portion of the evaporator 7. The hot gas bypass pipe 9 is provided with a hot gas bypass valve 10 for controlling the flow rate of the high-temperature refrigerant gas flowing through the hot gas bypass pipe 9.

The refrigerator 1 has a refrigeration cycle 11 having a pipe 12 that sequentially connects a compressor 2, a condenser 3, a first expansion valve 4, a second expansion valve 5, and an evaporator 7. Specifically, a pipe 12a that connects the compressor 2 and the condenser 3, a pipe 12b that connects the condenser 3 and the economizer 6, a pipe 12c that connects the economizer 6 and the evaporator 7, and an evaporator 7 and a pipe 12d for connecting the compressor 2 to each other.
As the refrigerant W, for example, alternative fluorocarbon R134a (hydrofluorocarbon) is used.
The piping 12 connecting the compressor 2 and the condenser 3 is provided with an acoustic device 13 that reduces noise generated in the compressor 2.

The compressor 2 is a centrifugal two-stage compressor, and is driven by an electric motor (not shown) whose rotational speed is controlled by an inverter that changes an input frequency from a power source.
The condenser 3 is a device that cools the refrigerant W compressed by the compressor 2 by heat exchange with cooling water or the like, and changes the state to a liquid state. For example, the condenser 3 is a shell and tube heat exchanger.

The first expansion valve 4 adiabatically expands and depressurizes the liquid refrigerant W from the condenser 3 to evaporate part of the liquid, thereby bringing the refrigerant W into a gas-liquid two-phase state.
The economizer 6 is a device that separates the refrigerant W, which is in a gas-liquid two-phase state in the first expansion valve 4, into a gas phase W1 and a liquid phase.

The inflow path 8 is a device that causes the gas phase W1 separated from the gas-liquid two-phase refrigerant W by the economizer 6 to flow into the compressor 2.
Similar to the first expansion valve 4, the second expansion valve 5 adiabatically expands and depressurizes the refrigerant W that is separated only by the economizer 6 and becomes only the liquid phase. In addition, in the refrigerator 1 of this embodiment, it is set as the structure which decompresses the refrigerant | coolant W using an expansion valve, However, It is not restricted to this, You may decompress the refrigerant | coolant W using another means.
The evaporator 7 evaporates the refrigerant W from the second expansion valve 5 by exchanging heat with water or the like to obtain a saturated vapor state.

  As shown in FIG. 2, the acoustic device 13 is provided in a pipe 12 a that connects the compressor 2 and the condenser 3. The acoustic device 13 is attached in the vicinity of the condenser 3 of the pipe 12a.

  As shown in FIGS. 3 and 4, the acoustic device 13 is provided on the outer peripheral side of the pipe 12 a, and includes a cavity forming portion 14 that forms a tubular cavity 16 surrounding the pipe 12 a, and a space S and a cavity in the pipe 12 a. And a first through-hole 23 that is a single communicating portion that communicates with the first through-hole 16.

  The cavity forming part 14 is a cylindrical member provided on the outer peripheral side of the pipe 12a over the entire circumference. The cavity forming part 14 defines a cavity 16 between the outer peripheral surface of the pipe 12a. The cavity forming portion 14 includes a pair of side wall portions 18 that are orthogonal to the piping axis Ad, and are provided over the entire circumference of the piping 12a, and a cylindrical portion 19 that is coaxial with the outer peripheral surface of the piping 12a. doing.

  The cavities 16 that are in contact with the pipe 12 communicate with the flow path in the pipe 12a. The first through hole 23 is formed in the pipe 12 a that is a wall portion on the radially inner side of the cavity 16. The first through-hole 23 is a communication portion that communicates the cavity 16 in contact with the outer peripheral surface of the pipe 12 and the inside of the pipe 12, and is formed only for the cavity 16 that is formed over the entire circumference in the circumferential direction. ing.

  The first through hole 23 is formed at the center of the cavity 16 in the axial direction. The first through hole 23 is circular. The area of the first through-hole 23 is set to 1/20 or less of the area A (cross-sectional area of the cross section including the axis Ad) viewed from the circumferential direction of the cavity 16. In other words, the area A viewed from the circumferential direction of the cavity 16 is 20 times or more the hole diameter of the first through hole 23. The shape of the first through hole 23 is not limited to a circular shape, and may be a rectangular shape or a slit shape.

  The volume of the cavity 16 and the hole diameter of the first through hole 23 can be appropriately adjusted according to desired sound absorption characteristics. In other words, the sound absorption characteristics of the acoustic device 13 can be adjusted by adjusting the volume of the cavity 16 and the hole diameter of the first through hole 23.

Next, the effect | action of the acoustic device 13 of the refrigerator 1 of this embodiment is demonstrated.
Of the noise generated in the compressor 2, for example, noise due to instability such as surging or turning stall becomes noise generated in a low frequency band. The acoustic device 13 of this embodiment can reduce noise generated in a low frequency band by having the annular cavity 16 surrounding the pipe 12a. That is, the gas in the cavity 16 serves as a spring and absorbs the kinetic energy of sound, thereby reducing noise. By forming the cavity 16 over the entire circumference, the acoustic device 13 having a larger resonance space can be obtained.
The refrigerator 1 of the present embodiment can adjust the sound absorption performance of the acoustic device 13 by adjusting the volume of the cavity 16 of the acoustic device 13 and the hole diameter of the first through hole 23.

FIG. 5 is a graph comparing the sound absorption performance of the acoustic device 13 with the vertical axis representing sound absorption performance and the horizontal axis representing noise frequency (Hz). The comparison target is an acoustic device having a plurality of cavities having a volume smaller than that of the cavity 16 of the present embodiment.
As shown in FIG. 5, the sound absorbing performance of the acoustic device 13 of the present embodiment can exhibit the sound absorbing performance with respect to noise in a lower frequency band as compared with an acoustic device having a plurality of cavities.

According to the embodiment, the noise can be reduced before the noise of the compressor 2 constituting the refrigerator 1 resonates with the resonance space.
In addition, a cavity forming portion 14 that forms an annular cavity 16 surrounding the pipe 12a is provided on the outer periphery of the pipe 12a, and the space S in the pipe 12a and the cavity 16 are communicated by a single first through hole 23. Thus, noise can be reduced in a larger resonance space. That is, the sound absorption characteristic of the acoustic device 13 can be a sound absorption characteristic that enables noise in a lower frequency band to be reduced.

  In the case of the refrigerator 1 having the compressor 2, the condenser 3, the expansion valves 4 and 5, the evaporator 7, and the refrigeration cycle 11 having the pipe 12 that sequentially connects them, an acoustic device that can be attached to the pipe 12 The size of 13 is limited. Since the acoustic device 13 of the present embodiment has a cylindrical shape provided on the outer peripheral side of the pipe 12, it can be attached to a narrow portion around the pipe 12.

  In addition, the sound absorbing performance of the acoustic device 13 can be adjusted by adjusting the volume of the cavity 16 of the acoustic device 13 and the hole diameter of the first through hole 23.

Next, an acoustic device according to a first modification of the embodiment of the present invention will be described.
As shown in FIG. 6, in the acoustic device 13 </ b> B according to the first modification of the embodiment of the present invention, the cavity forming portion 14 that forms the cavity 16 is stacked in a plurality of stages in the radial direction of the pipe 12. In other words, the acoustic device 13 </ b> B according to the first modification has the two-stage cavity 16 in the radial direction of the pipe 12.

  The cavity 16a formed by the radially inner cavity forming portion 14a and the cavity 16b formed by the radially outer cavity forming portion 14b communicate with each other through the second through hole 24 (cavity side communication portion). . The second through hole 24 is formed in the cylindrical portion 19 of the cavity forming portion 14 on the radially inner side.

  The first through hole 23 and the second through hole 24 are formed by shifting the phase in the circumferential direction of the pipe 12. The first through hole 23 and the second through hole 24 of the acoustic device 13 according to the first modification are 180 ° out of phase. In addition, the position of the 1st through-hole 23 and the 2nd through-hole 24 does not need to be shifted in phase, and the position of the circumferential direction of the piping 12 may be the same.

  According to the acoustic device 13 of the first modification, it is possible to improve the sound absorption performance without increasing the size of the cavity forming portion in the axial direction.

  Note that the number of cavities 14 is not limited to this, and may be three or more. The sound absorption performance of the acoustic device 13 can be adjusted by increasing or decreasing the number of the cavity forming portions 14.

Next, an acoustic device according to a second modification of the embodiment of the present invention will be described.
As shown in FIG. 7, the acoustic device 13 </ b> C according to the second modification of the embodiment of the present invention is provided with a plurality of cavity forming portions 14 so as to be adjacent in the axial direction of the pipe 12. That is, another cavity forming portion 14d is provided on one axial direction side of one cavity forming portion 14c. The side wall 18 on one side in the axial direction of one cavity forming portion 14c and the side wall 18 on the other side in the axial direction of the other cavity forming portion 14d may be common.

According to the acoustic device 13 of the second modified example, it is possible to improve the sound absorption performance without increasing the size of the cavity forming portion 14 in the radial direction.
Further, since a plurality of cavity forming portions 14 are provided so as to be adjacent to each other in the axial direction of the pipe 12, the sound absorbing performance of the acoustic device 13 can be adjusted by increasing or decreasing the number of the cavity forming portions 14.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design changes and the like within a scope not departing from the gist of the present invention. .

  In the above embodiment, the acoustic device 13 is installed in the pipe 12a between the compressor 2 and the condenser 3. However, the present invention is not limited to this. For example, the acoustic device 13 may be disposed in the pipes 12 b and 12 c between the condenser 3 and the evaporator 7, the pipe 12 d between the evaporator 7 and the compressor 2, and the hot gas bypass pipe 9. Furthermore, the number of acoustic devices 13 is not limited to one. For example, the acoustic devices 13 may be attached to all the pipes 12 or two may be attached to one pipe 12.

DESCRIPTION OF SYMBOLS 1 Refrigerator 2 Compressor 3 Condenser 4 1st expansion valve 5 2nd expansion valve 6 Economizer 7 Evaporator 8 Inflow path 9 Hot gas bypass pipe 10 Hot gas bypass valve 11 Refrigeration cycle 12 Piping 13 Acoustic device 14 Cavity formation part 16 Cavity 18 Side wall part 19 Cylindrical part 23 First through hole (communication part)
24 Second through hole (cavity side communication part)
W refrigerant

Claims (3)

A compressor, a condenser, an expander, an evaporator, and a refrigeration cycle having a pipe for sequentially connecting them;
A cavity forming portion provided on the outer peripheral side of the pipe to form an annular cavity surrounding the pipe;
A refrigerator comprising: a single communicating portion that communicates the space in the pipe with the cavity. A plurality of the cavity forming portions are provided so as to be adjacent in the radial direction of the pipe,
The refrigerator of Claim 1 provided with the single cavity side communication part which connects the cavity which adjoins the said radial direction.   The refrigerator according to claim 1 or 2, wherein a plurality of the cavity forming portions are provided so as to be adjacent to each other in the axial direction of the pipe.

Images