compressor

Abstract

The compressor (10) includes a compression mechanism (20) and a muffler structure (M) arranged on a blow-off flow path (38) that communicates a compression chamber outlet (26) of the compression mechanism (20) with an inflow end of a blow-off pipe (8), the muffler structure (M) being a first muffler portion (S1) and a second muffler portion (S2) that are connected in series so as to repeatedly expand and contract the refrigerant gas.

Description

Technical Field

[0001] This disclosure relates to a compressor. Background Technology

[0002] Patent Document 1 discloses a silencing device installed on a compressor. This silencing device suppresses noise caused by pressure fluctuations in the ejected refrigerant gas during its flow.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Publication No. 2014-47703 Summary of the Invention

[0006] -The technical problem the invention aims to solve-

[0007] When the silencer is installed outside the compressor, the distance from the nozzle of the compressor mechanism located inside the compressor to the silencer is relatively long. As a result, the refrigerant flowing in the pipes or oil collectors arranged between the nozzle of the compressor mechanism and the silencer will generate noise (refrigerant noise), which makes it sometimes difficult to ensure the quietness of the compressor.

[0008] The purpose of this disclosure is to improve the quietness of compressors with noise reduction function.

[0009] - Technical solutions for solving technical problems -

[0010] The first aspect of this disclosure relates to a compressor including a compression mechanism 20 and a muffler structure M, the muffler structure M being arranged between the compression chamber outlet 26 of the compression mechanism 20 and the inflow end of the ejector pipe 8, the muffler structure M being a first muffler section S1 and a second muffler section S2 connected in series to allow refrigerant gas to repeatedly expand and contract.

[0011] In the first aspect, by utilizing the first silencer section S1 and the second silencer section S2, the refrigerant gas flowing in the silencer structure M undergoes repeated expansion and contraction, resulting in reduced refrigerant noise pulsation. Since the silencer structure M is arranged between the compression chamber outlet 26 and the inlet end of the ejection pipe 8 from the compressor 10, the pressure pulsation of the refrigerant gas ejected from the compression chamber outlet 26 can be attenuated relatively upstream, thereby improving the pulsation reduction effect.

[0012] The second aspect of this disclosure, based on the first aspect, is that the muffler structure M is positioned closer to the compression chamber outlet 26 than closer to the inflow end of the ejector pipe 8, between the compression chamber outlet 26 and the inflow end of the ejector pipe 8.

[0013] In the second aspect, the refrigerant gas compressed by the compression mechanism 20 flows relatively quickly through the silencer structure M after being ejected from the compression chamber outlet 26. This allows the pressure pulsations of the refrigerant gas to be attenuated further upstream.

[0014] The third aspect of this disclosure, based on the first or second aspect, is that the refrigerant gas to which the muffler structure M is objected has an attenuation frequency of 3000 Hz or less, or an attenuation amount of 10 dB or more.

[0015] In the third aspect of this disclosure, the attenuation frequency of the refrigerant gas passing through the muffler structure M can be made to be less than 3000 Hz, or the attenuation amount can be more than 10 dB.

[0016] The fourth aspect of this disclosure, based on the first or second aspect, involves a refrigerant gas that is the object of the muffler structure M having an attenuation frequency of 2000 Hz or less, or an attenuation amount of 20 dB or more.

[0017] In the fourth aspect of this disclosure, the attenuation frequency of the refrigerant gas passing through the muffler structure M is made to be less than 2000 Hz, or the attenuation amount is more than 20 dB.

[0018] Based on any one of the first to fourth aspects, the fifth aspect of this disclosure provides that the muffler structure M has a first expansion space S1 and a second expansion space S2 with different volumes, wherein the first expansion space S1 is the first muffler section S1 and the second expansion space S2 is the second muffler section S2.

[0019] In the fifth aspect of this disclosure, since the volumes of the first expansion space S1 and the second expansion space S2 are different, the wavelengths of refrigerant noise in different frequency bands can be attenuated. This improves the refrigerant noise reduction effect.

[0020] The sixth aspect of this disclosure, based on the fifth aspect, further includes a housing 11, a plate portion 27, and a cover portion 31. The housing 11 has an opening 11a formed on the discharge side of the compressor 10. The plate portion 27 holds the shaft end of a drive shaft 18 disposed within the housing 11. The cover portion 31 is concave and is mounted on the housing 11 to seal the opening 11a. A silencer chamber SR is formed between the cover portion 31 and the plate portion 27. The silencer structure M is disposed in the silencer chamber SR.

[0021] In the sixth aspect, the silencing chamber SR is formed in an enclosed space between the plate portion 27 and the concave cover portion 31. Since the concave portion of the cover portion 31 is an inefficient space, the space inside the compressor 10 can be effectively utilized by placing the silencer structure M in such a space. Thus, for example, in the case where the silencer device is placed outside the compressor, it is necessary to install the compressor and the silencer device separately, while in the compressor of this disclosure, since the silencer structure M is arranged inside the compressor 10, the installation space of the compressor 10 can be saved.

[0022] The seventh aspect of this disclosure, based on the sixth aspect, is that the first expansion space S1 and the second expansion space S2 are formed by a spacer wall 37 disposed in the anechoic chamber SR.

[0023] In the seventh aspect, the first expansion space S1 and the second expansion space S2 can be formed simply by setting up the partition wall 37. In this way, the first expansion space S1 and the second expansion space S2 can be formed relatively easily, and there is no need to set up new silencing devices, etc., thereby saving costs.

[0024] The eighth aspect of this disclosure, based on the seventh aspect, wherein the partition wall 37 is integrally formed with the plate portion 27 or the cover portion 31.

[0025] In the eighth aspect, the partition wall 37 is integrally formed with the plate portion 27 or the cover portion 31. Therefore, the anechoic chamber SR can be constructed simply by mounting the cover portion 31 onto the plate portion 27. Thus, the silencer structure M can be formed relatively easily.

[0026] The ninth aspect of this disclosure, based on the eighth aspect, wherein the partition wall 37 has a first partition wall 37b that separates the first expansion space S1 from the second expansion space S2, and a first opening 39a that connects the first expansion space S1 and the second expansion space S2 is formed on the first partition wall 37b.

[0027] In the ninth aspect, the refrigerant gas flowing from one of the first expansion space S1 and the second expansion space S2 to the other contracts at the first opening 39a. Thus, by providing the first opening 39a on the first partition wall 37b, the silencer structure M can be formed relatively easily.

[0028] In the tenth aspect, based on the ninth aspect, the compressor further includes a pipe 72, which is connected to the outlet end of the muffler structure M and communicates with the inlet end of the ejector pipe 8.

[0029] In the tenth aspect, by adjusting the length of the tube, the desired reduction in refrigerant noise can be achieved.

[0030] In the eleventh aspect, based on any one of the first to tenth aspects, the muffler structure M includes a main flow path 41 and a secondary flow path 42. The main flow path 41 is a flow path for refrigerant gas to flow through the first muffler section S1 and the second muffler section S2. The secondary flow path 42 is a flow path for refrigerant gas to flow back into the main flow path 41 after being diverted from it.

[0031] In the eleventh aspect, the refrigerant gas flows through the main flow path 41 and the secondary flow path 42. By providing multiple flow paths for the refrigerant gas, a reduction in refrigerant noise can be achieved.

[0032] According to the twelfth aspect, based on any one of the first to tenth aspects, the muffler structure M includes a main flow path 41 and a branch flow path 43. The main flow path 41 is a flow path for refrigerant gas to flow through the first muffler section S1 and the second muffler section S2. The branch flow path 43 is a flow path branching off from the main flow path 41. The outlet end of the branch flow path 43 is closed.

[0033] In the twelfth aspect, since the outlet end of the branch flow path 43 is closed, the refrigerant noise of the refrigerant flowing into the branch flow path 43 will be canceled out due to resonance. In this way, a refrigerant noise reduction effect can be achieved.

[0034] Based on any one of the first to twelfth aspects, the flow path length of the muffler structure M is 50 mm to 2000 mm.

[0035] In the thirteenth aspect, it is able to suppress frequency bands within a specified range.

[0036] Based on any one of the first to thirteenth aspects, the compressor further includes a sound-absorbing material disposed on the first silencer section S1 or the second silencer section S2.

[0037] In the fourteenth aspect, the use of sound-absorbing materials can improve the reduction effect of refrigerant noise. Attached Figure Description

[0038] Figure 1 It is a schematic diagram of the refrigerant circuit of a refrigeration device including the compressor involved in the embodiments;

[0039] Figure 2 This is a longitudinal sectional view showing a simplified structure of the compressor involved in the embodiment;

[0040] Figure 3 This is a 3D view of an oil separator; Figure 3 This indicates the state of the cover when viewed from the front side;

[0041] Figure 4A It is a perspective view showing the longitudinal cross-section of the anechoic chamber; Figure 4A This indicates the condition of the silencing chamber as observed from the bearing support side;

[0042] Figure 4B It is a perspective view showing the longitudinal cross-section of the anechoic chamber; Figure 4B This indicates the state of the anechoic chamber as observed from the side of the cover.

[0043] Figure 5A This is a longitudinal sectional view of the anechoic chamber involved in Modified Example 1; Figure 5A This indicates the condition of the silencing chamber as observed from the bearing support side;

[0044] Figure 5B This is a longitudinal sectional view of the anechoic chamber involved in Modified Example 1; Figure 5B This indicates the state of the anechoic chamber as observed from the side of the cover.

[0045] Figure 6A This is a longitudinal sectional view of the anechoic chamber involved in Modified Example 2; Figure 6A This indicates the condition of the silencing chamber as observed from the bearing support side;

[0046] Figure 6B This is a longitudinal sectional view of the anechoic chamber involved in Modified Example 2; Figure 6B This indicates the state of the anechoic chamber as observed from the side of the cover.

[0047] Figure 7A This is a longitudinal sectional view of the anechoic chamber involved in other embodiments; Figure 7A This indicates the condition of the silencing chamber as observed from the bearing support side;

[0048] Figure 7B This is a longitudinal sectional view of the anechoic chamber involved in other embodiments; Figure 7B This indicates the state of the anechoic chamber as observed from the side of the cover. Detailed Implementation

[0049] The embodiments of the present invention will now be described with reference to the accompanying drawings. It should be noted that the following embodiments are merely preferred examples and are not intended to limit the scope of the present invention, its application, or its uses. The various embodiments, modifications, and other examples described below can be combined or partially substituted within the scope of implementing the present invention.

[0050] (Implementation Method)

[0051] like Figure 1As shown, the compressor 10 of the embodiment is connected in the refrigerant circuit 3 of the refrigeration device 1. In the refrigerant circuit, for example, the compressor 10, radiator 5, pressure reducing unit 9, and evaporator 6 are connected in sequence. A discharge pipe 8 is provided between the compressor 10 and the radiator 5, and the compressed refrigerant is sprayed into the discharge pipe 8. The refrigerant circuit performs a vapor compression refrigeration cycle. Specifically, the refrigerant compressed by the compressor 10 releases heat in the radiator 5. The refrigerant after releasing heat is depressurized by the pressure reducing unit 9. The refrigerant after depressurization by the pressure reducing unit 9 evaporates in the evaporator 6. The refrigerant evaporated in the evaporator 6 is drawn into the compressor 10. In this example, the compressor 10 has an oil separator 30.

[0052] <compressor>

[0053] Compressor 10 compresses the refrigerant. Compressor 10 draws in low-pressure gaseous refrigerant and compresses it. Compressor 10 then ejects the compressed, high-pressure gaseous refrigerant. Figure 2 As shown, compressor 10 is a screw compressor. Compressor 10 is a single-screw compressor having a screw rotor 22. Compressor 10 is a single-guillotine compressor having a guillotine rotor 23. Compressor 10 includes a housing 11, an electric motor 15, a drive shaft 18, and a compression mechanism 20.

[0054] <chassis>

[0055] The housing 11 is formed as a cylindrical shape with a relatively long transverse length. Inside the housing 11 are a low-pressure chamber L and a high-pressure chamber H. The low-pressure chamber L forms a flow path for the low-pressure gaseous refrigerant drawn into the compression mechanism 20. The high-pressure chamber H forms a flow path for the high-pressure gaseous refrigerant ejected from the compression mechanism 20.

[0056] A suction hood 12 is installed at one end of the housing 11 along its length. An opening 11a is formed at the other end of the housing 11 along its length. The opening 11a is formed on the discharge side of the compressor 10. Specifically, the opening 11a is provided on the high-pressure side of the housing 11 where the high-pressure chamber H is formed. A cover 31 of an oil separator 30 is installed on the opening 11a. An oil chamber 14 for storing oil is formed at the bottom inside the housing 11.

[0057] <Electric motor>

[0058] The electric motor 15 is housed in the housing 11. The electric motor 15 has a stator 16 and a rotor 17. The stator 16 is fixed to the inner wall of the housing 11. The rotor 17 is arranged inside the stator 16. A drive shaft 18 is fixed inside the rotor 17.

[0059] <Drive shaft>

[0060] Drive shaft 18 connects motor 15 and compression mechanism 20. Drive shaft 18 extends along the length of housing 11. Drive shaft 18 extends in a generally horizontal direction. Drive shaft 18 is supported by a plurality of bearings 19 and is rotatable. The shaft end of drive shaft 18 located on the opening side of housing 11 is held by bearing bracket 27 arranged within housing 11. Specifically, the shaft end of drive shaft 18 is held by bearings 19 formed in bearing bracket 27. Bearing bracket 27 is a plate portion of this disclosure.

[0061] <Compression Mechanism>

[0062] The compression mechanism 20 has a cylinder section 21, a screw rotor 22 and a brake rotor 23.

[0063] A cylinder section 21 is formed inside the housing 11. A screw rotor 22 is arranged inside the cylinder section 21. The screw rotor 22 is fixed to the drive shaft 18. Multiple helical screw grooves 24 (three in this example) are formed on the outer peripheral surface of the screw rotor 22. The outer peripheral surface of the tooth tips of the screw rotor 22 is surrounded by the cylinder section 21. One axial end of the screw rotor 22 faces the low-pressure chamber L. The other axial end of the screw rotor 22 faces the high-pressure chamber H.

[0064] The brake rotor 23 is housed in the brake rotor chamber 25. The brake rotor 23 has a plurality of brakes 23a arranged radially. The brakes 23a of the brake rotor 23 penetrate a portion of the cylinder section 21 and engage with the screw groove 24. The compression mechanism 20 has an intake port, a compression chamber, and an exhaust port 26. The intake port is the portion of the screw groove 24 that opens into the low-pressure chamber L. The compression chamber is formed between the inner circumferential surface of the cylinder section 21, the screw groove 24, and the brakes 23a.

[0065] The nozzle 26 is the portion that opens into the high-pressure chamber H. In the compression mechanism 20, the refrigerant, compressed in the compression chamber, is ejected into the high-pressure chamber H through the nozzle 26. The nozzle 26 is formed on the other axial end side of the screw rotor 22 (see reference). Figure 1 (Double-dotted line in the text). The nozzle 26 is the compression chamber outlet 26 of the compression mechanism 20 of this disclosure. The nozzle 26 is connected to the inlet end of the ejection pipe 8. An ejection flow path 38 for refrigerant gas flow is formed between the nozzle 26 and the inlet end of the ejection pipe 8.

[0066] The compression mechanism 20 has a slide valve mechanism (not shown). The slide valve mechanism adjusts the timing of communication between the compression chamber and the nozzle. The slide valve mechanism includes a sliding member (slide valve) that moves forward and backward in the longitudinal direction along the axis of the drive shaft 18. A portion of the sliding member is located within the high-pressure chamber H.

[0067] Oil separator

[0068] The oil separator 30 is a centrifugal separator that uses centrifugal force to separate oil from the refrigerant. The oil separator 30 separates oil from the refrigerant sprayed from the self-compressing mechanism 20. The oil separator 30 includes a cover 31, a cylindrical oil separator body 50, and a bent pipe 70. See below for reference. Figure 2 and Figure 3 This section provides an explanation. It should be noted that in the following explanation, statements related to "up," "down," "right," "left," "front," and "back" will generally use the prefix "up," "down," "right," "left," "front," and "back." Figure 3 The case shown is based on the view of the cover 31 from the front.

[0069] <Cover section>

[0070] The cover 31 is mounted on the housing 11 to seal the opening 11a. The cover 31 encloses the high-pressure chamber H of the compressor 10. A silencer chamber SR is formed between the cover 31 and the bearing support 27. The cover 31 has a cover body 32 and a flange 33.

[0071] The main body 32 is formed as a hollow (concave) structure with an open front side. The main body 32 has a right side wall 32c, a left side wall 32b, an upper wall 32a, a bottom wall 32d, and an inner side wall 32e. When viewed from the front, the bottom wall 32d is formed in an approximately semi-cylindrical shape, bulging downwards. The main body 32 has a partition wall 34. The partition wall 34 extends horizontally from the lower end of the right side wall 32c to the lower end of the left side wall 32b. The partition wall 34 divides the interior of the cover 31 into an oil storage space 35 and an ejection space 36.

[0072] The oil storage space 35 is a space divided by the partition wall 34 and the bottom wall 32d. For example... Figure 2 As shown, the oil storage space 35 is located at a height corresponding to the oil chamber 14 inside the housing 11. The oil separated in the oil separator 30 is stored in the oil storage space 35.

[0073] The ejection space 36 is formed by the opening on the front side of the cover body 32 covered by the bearing bracket 27. Specifically, the ejection space 36 is formed by the partition wall 34, the left side wall 32b, the right side wall 32c, the upper wall 32a, the inner side wall 32e, and the bearing bracket 27. The ejection space 36 is located at a height corresponding to the high-pressure chamber H inside the housing 11. High-pressure gaseous refrigerant ejected by the compression mechanism 20 flows into the ejection space 36. A silencer chamber SR is provided in the ejection space 36.

[0074] A flange portion 33 is provided at the front end of the cover body 32. The flange portion 33 is formed into a frame shape with a relatively long longitudinal length in the vertical direction. The flange portion 33 is fixed to the edge of the opening 11a of the housing 11 by fastening components. The flange portion 33 includes a first flange portion 33a and a second flange portion 33b. The first flange portion 33a is connected to the front ends of the upper wall 32a, the left side wall 32b, and the right side wall 32c, respectively. Thus, when viewed from the front, the first flange portion 33a forms an inverted U-shape. The second flange portion 33b is connected to the front end of the bottom wall 32d. Thus, when viewed from the front, the second flange portion 33b forms a U-shape.

[0075] Oil separator

[0076] The oil separator body 50 is cylindrical. Strictly speaking, the oil separator body 50 is a hollow cylindrical shape. Inside the oil separator body 50, a separation space 51 is formed for separating oil from the refrigerant by means of centrifugal force. The refrigerant flowing through the bend 70 flows into the separation space 51. The oil separator body 50 has an outer cylinder 52 and a cover component 60.

[0077] The outer cylinder 52 is formed as a bottomed cylinder with an opening on the upper side. The outer cylinder 52 includes a cylindrical body 53 and a bottom 54 formed on the lower side of the body 53.

[0078] The front portion of the body 53 is integrally formed with the cover 31. An oil outlet hole 55 is formed on the body 53. Oil in the separation space 51 flows out through the oil outlet hole 55 into the oil storage space 35.

[0079] An oil return path 56 is formed at the bottom 54. The oil return path 56 is a path for supplying oil from the oil storage space 35 to the designated lubrication parts of the compressor 10.

[0080] The cover component 60 is installed on the upper opening of the outer cylinder 52. The cover component 60 has an upper cover 61 and an inner cylinder 62.

[0081] The upper cover 61 is formed into an approximately circular plate shape. The upper cover 61 is fixed to the upper end of the outer cylinder 52 by fastening components.

[0082] The inner cylinder 62 is formed into a cylindrical shape that is open at both ends. The inner cylinder 62 protrudes downward from the upper cover 61.

[0083] A space is formed inside the inner cylinder 62 that connects the separation space 51 to the ejector pipe 8. The opening at the upper end of the inner cylinder 62 is connected to the inflow end of the ejector pipe 8.

[0084] The bend 70 introduces high-pressure refrigerant containing oil into the oil separator body 50. The bend 70 is arranged to circumferentially surround the body 53 of the oil separator body 50. An internal flow path 70a is formed inside the bend 70, curving along the bend 70.

[0085] The inlet end of the bend 70 is connected to the outlet 45 formed in the ejection space 36. The outlet 45 is described below.

[0086] In this example, in the compressor 10, the flow path from the nozzle 26 to the inlet end of the nozzle pipe 8 forms an outlet flow path 38 for the refrigerant compressed by the compression mechanism 20 to flow.

[0087] -Detailed information about the muffler structure-

[0088] Reference Figure 3 , Figure 4A and Figure 4B The structure M of the muffler is described. Figure 4A and Figure 4B The following diagram shows the muffler 72 installed in the anechoic chamber SR. It should be noted that... Figure 4A and Figure 4B In the text, the shading lines representing the cross-section are omitted.

[0089] The silencer structure M is formed in the silencing chamber SR. The silencing chamber SR is arranged on the ejection flow path 38 between the nozzle 26 and the inlet end of the ejection pipe 8. The silencer structure M consists of a first silencer section S1 and a second silencer section S2. The first silencer section S1 and the second silencer section S2 are connected in series to allow the refrigerant gas to repeatedly expand and contract. Details regarding the first silencer section S1 and the second silencer section S2 are described below.

[0090] The silencing chamber SR is formed between the shroud body 32 and the bearing support 27. Specifically, the silencing chamber SR is formed in the ejection space 36. The silencing chamber SR has an inlet 44, an outlet 45, and a partition wall 37.

[0091] Inlet 44 is formed on bearing support 27. Inlet 44 is located in the upper left part of bearing support 27. Refrigerant ejected from nozzle 26 of compressor 20 flows into silencing chamber SR through inlet 44.

[0092] An outlet 45 is formed on the cover 31. The outlet 45 is located on the upper right portion of the inner sidewall 32e of the cover 31. The outlet 45 communicates with the ejection path 38. The refrigerant in the silencing chamber SR flows out from the outlet 45 into the ejection path 38.

[0093] The partition wall 37 has a main partition wall 37a, a first partition wall 37b, a second partition wall 37c, and a third partition wall 37d. Each partition wall 37 is integrally formed with the cover body 32. With the bearing bracket 27 installed on the cover body 32, the front end of each partition wall 37 is tightly engaged with the bearing bracket 27.

[0094] The main partition wall 37a forms a first flow path 40 for refrigerant gas flowing from the inlet 44 to the outlet 45. Specifically, the main partition wall 37a extends from the upper wall 32a toward the partition wall 34, passing between the inlet 44 and the outlet 45. Thus, the first flow path 40 is U-shaped. More specifically, through the first flow path 40, the refrigerant gas flowing in from the inlet 44 flows downward through the left side of the anechoic chamber SR, then flows upward through the right side of the anechoic chamber SR, and finally exits from the outlet 45 outside the anechoic chamber SR.

[0095] Four spaces S1 to S4 are formed in the first flow path 40. The four spaces S1 to S4 are arranged sequentially along the refrigerant flow direction: first space S1, second space S2, third space S3, and fourth space S4. The first space S1 to the fourth space S4 are formed by partition walls 37. The first partition walls 37b to the third partition walls 37d are arranged such that the volumes of the first space S1 to the fourth space S4 are different from each other.

[0096] The first space S1 is the first silencer section S1 of this disclosure. The first space S1 is formed on the first flow path 40 at the location where the inlet 44 is arranged. The first space S1 is a space on the first flow path 40 separated by the first partition wall 37b. Specifically, the first space S1 is divided by the left side wall 32b, the main partition wall 37a, the upper wall 32a, the first partition wall 37b, the inner side wall 32e, and the bearing support 27. The first partition wall 37b connects the left side wall 32b and the main partition wall 37a. The first partition wall 37b is arranged at the lower end of the main partition wall 37a. If the first space S1 is defined as the first expansion space S1 of this disclosure, and the second space S2 is defined as the second expansion space S2 of this disclosure, then the first partition wall 37b separates the first expansion space S1 and the second expansion space S2. The flow path length of the refrigerant gas in the first space S1 is defined as L1. L1 is the length between the surfaces of the upper wall 32a and the first partition wall 37b that are opposite each other.

[0097] A first opening 39a is formed on the first partition wall 37b. The first opening 39a connects the first space S1 and the second space S2. The first opening 39a is circular. The first opening 39a is formed by a first inner peripheral surface F1 formed on the first partition wall 37b. A first small space ss1 surrounded by the first inner peripheral surface F1 is formed on the first partition wall 37b.

[0098] The second space S2 is the second silencer section S2 of this disclosure. The second space S2 is connected in series with the first space S1. The second space S2 is a space separated by a first partition wall 37b and a second partition wall 37c on the first flow path 40. Specifically, the second space S2 is formed by the first partition wall 37b, the second partition wall 37c, the left side wall 32b, the right side wall 32c, the partition wall 34, the inner side wall 32e, and the bearing support 27. The second partition wall 37c connects the right side wall 32c to the main partition wall 37a. The second partition wall 37c is arranged at the lower end of the main partition wall 37a. The flow path length of the refrigerant gas in the second space S2 is defined as L2. L2 is the length between the faces of the left side wall 32b and the right side wall 32c that are opposite each other.

[0099] A second opening 39b is formed on the second partition wall 37c. The second opening 39b connects the second space S2 and the third space S3. The second opening 39b is circular. The second opening 39b is formed by the second inner peripheral surface F2 formed on the second partition wall 37c. A second small space ss2 surrounded by the second inner peripheral surface F2 is formed on the second partition wall 37c.

[0100] The third space S3 is a space separated by the second partition wall 37c and the third partition wall 37d on the first flow path 40. Specifically, the third space S3 is divided by the second partition wall 37c, the third partition wall 37d, the main partition wall 37a, the right side wall 32c, the inner side wall 32e, and the bearing support 27. The third partition wall 37d connects the right side wall 32c and the main partition wall 37a. The third partition wall 37d is located closer to the upper wall 32a than the middle height of the main partition wall 37a. The flow path length of the refrigerant gas in the third space S3 is defined as L3. L3 is the length between the faces of the second partition wall 37c and the third partition wall 37d that are opposite each other.

[0101] A third opening 39c is formed on the third partition wall 37d. The third opening 39c connects the third space S3 and the fourth space S4. The third opening 39c is circular. The third opening 39c is formed by the third inner circumferential surface F3 formed on the third partition wall 37d. A third small space ss3 is formed on the third partition wall 37d and surrounded by the third inner circumferential surface F3.

[0102] The fourth space S4 is formed on the first flow path 40 at the location where the outlet 45 is arranged. The fourth space S4 is a space separated on the first flow path 40 by the third partition wall 37d. Specifically, the fourth space S4 is divided by the third partition wall 37d, the main partition wall 37a, the right side wall 32c, the upper wall 32a, the inner side wall 32e, and the bearing support 27. The flow path length of the refrigerant gas in the fourth space S4 is defined as L4. L4 is the length between the faces of the third partition wall 37d and the upper wall 32a that are opposite each other.

[0103] The first partition wall 37b to the third partition wall 37d are arranged such that the flow path lengths L1 to L4 are all different. As a result, the volumes of the first space S1 to the fourth space S4 are all different.

[0104] -Tube-

[0105] Pipe 72 is installed in the silencing chamber SR.

[0106] The tube 72 is formed into a cylindrical shape. The outer circumferential surface of the tube 72 is fixed at the second opening 39b (second inner circumferential surface F2) and the third opening 39c (third inner circumferential surface F3). The inflow end of the tube 72 communicates with the second space S2. The outflow end of the tube 72 is connected to the outlet 45. The length from the inflow end to the outflow end of the tube is defined as d1.

[0107] The tube 72 has an inner tube portion 73. The inner tube portion 73 is the portion of the tube 72 that protrudes downward from the second opening. The inner tube portion 73 includes the inlet end of the tube. The length of the inner tube is defined as d2.

[0108] Multiple holes 74 are formed on the tube 72. The multiple holes 74 are formed at positions corresponding to the third space S3.

[0109] Sound-absorbing materials are installed in the anechoic chamber SR. These materials are placed in the first space S1, the second space S2, and the third space S3. Examples of sound-absorbing materials include glass wool, steel wool, and porous materials.

[0110] - Flow of refrigerant gas -

[0111] Refrigerant gas ejected from the nozzle 26 of the compression mechanism 20 flows into the silencing chamber SR through the inlet 44. The refrigerant gas flowing into the silencing chamber SR sequentially passes through the first space S1, the first small space SS1, the second space S2, and the pipe 72. The refrigerant gas expands in the first space S1, contracts in the first small space SS1, and expands again in the second space S2. The refrigerant gas flowing from the first space S1 into the pipe 72 exits from the outlet 45.

[0112] In this way, by connecting the first space S1 and the second space S2 in series via the first small space ss1, the refrigerant gas repeatedly expands and contracts. The length of the muffler structure including the first space S1 and the second space S2 is, for example, 50 mm to 2000 mm. The flow path length L1 of the first space S1 and the flow path length L2 of the second space are set such that the attenuation frequency of the refrigerant gas flowing through the muffler structure M is below 3000 Hz, or the attenuation is above 10 dB.

[0113] - Reduction of refrigerant noise -

[0114] In a compressor like this embodiment, pressure pulsations are generated in the discharge pipe due to the flow of compressed, high-pressure refrigerant. These pressure pulsations cause refrigerant noise. Specifically, the pressure pulsations include frequency components determined by the product of the screw rotor's rotational speed and the number of teeth on the screw rotor. Changing the screw rotor's rotational speed generates frequency components corresponding to that speed, thus creating pressure pulsations in the discharge pipe that contain multiple frequency components.

[0115] Some solutions have been proposed to suppress refrigerant noise. For example, in some solutions, a silencer is installed on the outside of the compressor on the discharge pipe; in others, the thick-walled part inside the compressor is machined to form a sound-absorbing space, and resonance is used to suppress refrigerant noise, and so on.

[0116] However, when the silencer is installed outside the compressor, the distance from the compressor outlet to the silencer is relatively long, which may generate noise due to the refrigerant flowing in the pipes or oil separators arranged between the compressor outlet and the silencer. Furthermore, since the silencer is connected outside the compressor, sufficient space must be ensured for its installation. Moreover, when the silencer space is formed inside the compressor, design freedom is relatively limited; for example, a silencer space cannot be formed without thick-walled sections, and creating a silencer space may increase manufacturing costs.

[0117] To address these issues, the compressor 10 of this embodiment includes a muffler structure M, which is arranged on the ejection flow path 38 that connects the compression chamber outlet 26 of the compression mechanism 20 to the inflow end of the ejection pipe 8. The muffler structure M consists of a first space S1 (first muffler section) and a second space S2 (second muffler section), which are connected in series to allow the refrigerant gas to repeatedly expand and contract.

[0118] According to this embodiment, the refrigerant gas flowing in the first flow path 40 is repeatedly expanded and contracted using the first space S1 and the second space S2, resulting in reduced refrigerant noise pulsation. The first space S1 and the second space S2, serving as a muffler structure M, are arranged between the nozzle 26 and the inlet end of the nozzle pipe 8 within the compressor 10. Therefore, the pressure pulsation of the refrigerant gas ejected from the nozzle 26 can be attenuated relatively upstream, thereby improving the pulsation reduction effect.

[0119] Furthermore, since the pressure pulsation of the refrigerant gas can be attenuated relatively upstream by utilizing the muffler structure M, it is possible to suppress the vibration of components located downstream of the muffler structure M.

[0120] In this embodiment, the muffler structure M of the compressor 10 is located on the discharge flow path 38 closer to the discharge outlet 26 than to the inflow end of the discharge pipe 8.

[0121] According to this embodiment, the nozzle 26 and the inlet 44 of the silencing chamber SR are located relatively close to each other, and the first space S1 is formed at the inlet 44 of the silencing chamber SR. Therefore, the compressed high-pressure refrigerant gas flows into the silencing chamber SR immediately after being ejected from the nozzle 26, and is silenced by the muffler structure M. In this way, pressure pulsations of refrigerant noise can be suppressed at a more upstream location. In particular, in this example, since the nozzle 26 is directly connected to the muffler structure M, the first wavelength of the pressure pulsation can be suppressed, resulting in improved pulsation reduction effect. It should be noted that the pressure pulsation here includes the pressure pulsation with the product of the number of slots of the compression mechanism 20 and the operating frequency as the primary component.

[0122] In this embodiment, the refrigerant gas of the compressor 10, which is the target of the muffler structure M, has an attenuation frequency of 3000 Hz or less, or an attenuation amount of 10 dB or more. In this example, the lengths of L1 and L2 can be easily changed by adjusting the position of the first partition wall 37b provided on the cover 31. Furthermore, the desired refrigerant gas flow rate and noise reduction effect can be adjusted simply by changing the opening area of ​​the first small space ss1. In this way, by changing the position of the first partition wall 37b or the opening area of ​​the first small space ss1, a muffler structure M with a high degree of design freedom can be constructed.

[0123] The muffler structure M of the compressor 10 in this embodiment has a first space S1 (first expansion space) and a second space S2 (second expansion space) with different volumes. The first space S1 is the first muffler section S1, and the second space S2 is the second muffler section S2. In this way, the wavelengths of refrigerant noise in different frequency bands can be attenuated in the first space S1 and the second space S2. As a result, the refrigerant noise reduction effect can be improved.

[0124] The compressor 10 of this embodiment includes a concave cover 31, which is mounted on the housing 11 to seal the opening 11a of the housing 11, and a silencing chamber SR is formed between the cover 31 and the bearing bracket 27 (plate). A silencer structure M is disposed in the silencing chamber SR.

[0125] According to this embodiment, the silencer chamber SR is formed in the enclosed space between the bearing support 27 and the cover 31. Since the recess of the cover 31 is an inefficient space, the space inside the compressor 10 can be effectively utilized by placing the silencer structure M in such a space. In this way, for example, if the silencer structure M is placed outside the compressor, it is necessary to install the compressor 10 and the silencer structure M separately. However, in the compressor 10 of this disclosure, since the silencer structure M is arranged inside the compressor 10, the installation space of the compressor 10 can be saved.

[0126] In the compressor 10 of this embodiment, the first space S1 (first expansion space) and the second space (second expansion space) are formed by a partition wall 37 provided in the silencing chamber SR. This allows for the simple formation of the first space S1 and the second space S2 without requiring new silencing devices, thus saving costs. Furthermore, the desired noise reduction effect can be achieved simply by adjusting the position of the partition wall.

[0127] In the compressor 10 of this embodiment, the partition wall 37 and the cover 31 are formed as one piece. In this way, the muffler structure M can be formed relatively easily simply by mounting the cover 31, on which the partition wall 37 is integrally formed, onto the plate 27.

[0128] In the compressor 10 of this embodiment, the partition wall 37 has a first partition wall 37b that separates the first space S1 and the second space S2. A first opening 39a that connects the first space S1 and the second space S2 is formed on the first partition wall 37b. In this way, the first space S1 and the second space S2 can be formed relatively easily by simply providing the first partition wall 37b.

[0129] In the compressor 10 of this embodiment, a pipe 72 is also included, which is connected to the outlet end of the muffler structure M and communicates with the inlet end of the ejector pipe 8. The target frequency band can be set using the length d1 of the pipe 72. This reduces refrigerant noise in the desired frequency band. In particular, by setting the length of the pipe d1 according to the length L1 of the first space S1 and the length L2 of the second space S2, a relatively high noise reduction effect can be achieved.

[0130] Furthermore, in this example, a plurality of holes 74 are formed on the tube 72. These holes 74 are located at positions corresponding to the enclosed third space S3. In this way, when refrigerant gas flows through the tube 72, the resonance generated by the plurality of holes 74 can be used to reduce refrigerant noise. This suppresses refrigerant noise from the refrigerant passing through the formed tube 72.

[0131] Furthermore, an inner insertion tube portion 73 is formed on the tube 72 in this example. By appropriately setting the length d2 of the inner insertion tube portion 73, a relatively high noise reduction effect can be achieved.

[0132] In the compressor 10 of this embodiment, the flow path length of the muffler structure M is 50 mm to 2000 mm. This allows for the suppression of refrigerant noise wavelengths with frequencies ranging from 75 Hz to 3000 Hz.

[0133] In the compressor 10 of this embodiment, sound-absorbing material is provided on the inner walls of the first muffler section S1 and the second muffler section S2. Specifically, the sound-absorbing material is attached to the inner walls of the first expansion space to the third expansion space S and the first small space to the second small space ss. In this way, the refrigerant noise reduction effect can be further improved.

[0134] <Variation Example 1>

[0135] Reference Figure 5A and Figure 5B The compressor 10 according to Modification Example 1 will be described below. Hereinafter, the structure that differs from the compressor 10 of the above embodiment will be described.

[0136] In this example, no pipe 72 is installed in the anechoic chamber SR. A fourth opening 39d is formed on the main partition wall 37a, connecting the first space S1 and the third space S3. The fourth opening 39d is circular. The main partition wall 37a has a fourth inner circumferential surface F4 on which the fourth opening 39d is formed. A fourth small space ss4 surrounded by the fourth inner circumferential surface F4 is formed on the main partition wall 37a. In this example, the first flow path 40 has a main flow path 41 and a secondary flow path 42.

[0137] Mainstream path 41 is a flow path through which refrigerant gas flows sequentially through the first space S1, the first small space ss1, the second space S2, the second small space ss2, the third space S3, the third small space ss3, and the fourth space S4.

[0138] The secondary flow path 42 is a flow path through which refrigerant gas flowing from the inlet 44 to the outlet 45 is diverted from the main flow path 41 and then rejoins the main flow path 41. Specifically, the secondary flow path 42 is a fourth sub-space ss4 that connects the first space S1 and the third space S3.

[0139] - Flow of refrigerant gas -

[0140] After flowing in from inlet 44, a portion of the refrigerant gas passing through the first space S1 flows sequentially through the first subspace SS1, the second space S2, the second subspace SS2, the third space S3, the third subspace SS3, and the fourth space S4, thus repeatedly expanding and contracting. The remaining portion of the refrigerant gas passing through the first space S1 flows sequentially through the fourth subspace SS4, the third space S3, the third subspace SS3, and the fourth space S4, thus repeatedly expanding and contracting.

[0141] As in this example, in the anechoic chamber SR, the flow path length from the inlet 44 to the outlet 45 is different when the refrigerant gas flows in the main flow path 41 and when the refrigerant gas flows in the secondary flow path 42. Because the anechoic chamber SR in this example has flow paths for refrigerant gas with different flow path lengths, it is possible to reduce refrigerant noise with multiple frequencies.

[0142] <Variation Example 2>

[0143] Reference Figure 6A and Figure 6B The compressor 10 involved in Modification Example 2 will be described below. Hereinafter, the structure that differs from that of the compressor 10 in Modification Example 1 will be described.

[0144] The anechoic chamber SR in this example has a fourth partition wall 37e. The fourth partition wall 37e extends from the lower end of the main partition wall 37a to the partition wall 34. The second space S2 is divided into two spaces in the left-right direction by the fourth partition wall 37e. The left portion of the second space S2 divided by the fourth partition wall 37e is designated as the left second space S2a, and the right portion of the second space S2 divided by the fourth partition wall 37e is designated as the right second space S2b. The volume of the left second space S2a is different from the volume of the right second space S2b. The first flow path 40 in this example has a main flow path 41 and a branch flow path 43.

[0145] Mainstream path 41 is the flow path through which refrigerant gas flows sequentially through the first space S1, the fourth small space ss4, the third space S3, the third small space ss3, and the fourth space S4.

[0146] Branch flow path 43 is a flow path branching off from the main flow path 41. The outflow end of branch flow path 43 is closed. In this example, branch flow path 43 has a first branch flow path 43a and a second branch flow path 43b. The first branch flow path 43a is composed of a first small space ss1 and a left second space S2a. The second branch flow path 43b is composed of a second small space ss2 and a right second space S2b.

[0147] - Flow of refrigerant gas -

[0148] The refrigerant gas flowing into the anechoic chamber SR from inlet 44 sequentially passes through the first space S1, the fourth small space ss4, the third space S3, the third small space ss3, and the fourth space S4, thereby repeatedly expanding and contracting. Sound waves near the resonance frequency are blocked from propagating by the first branch flow path 43a and the second branch flow path 43b. In this way, refrigerant noise at the same frequency as the resonance frequency generated by the refrigerant gas flowing in the main flow path 41 can be suppressed. Thus, in this example, by providing branch flow paths 43 in the anechoic chamber SR, the attenuation effect of refrigerant noise can be improved.

[0149] (Other implementation methods)

[0150] The above implementation method can also adopt the following structure.

[0151] The muffler structure M can also be configured such that the refrigerant gas attenuation frequency is below 2000Hz, or the attenuation amount is above 20dB.

[0152] like Figure 7A and Figure 7B As shown, the tube 72 can also be fixed to the second opening 39b and the third opening 39c by interlocking. Specifically, the second opening 39b has a first recess r1 formed circumferentially along the second inner circumferential surface F2. The third opening 39c has a second recess r2 formed circumferentially along the third inner circumferential surface F3. A first protrusion c1 and a second protrusion c2 are formed circumferentially on the outer circumferential surface of the tube 72. The first protrusion c1 of the tube is fitted into the first recess r1 of the second opening, and the second protrusion c2 of the tube is fitted into the second recess r2 of the third opening, thereby fixing the tube 72 at the second opening 39b and the third opening 39c. In this way, displacement of the tube 72 within the anechoic chamber SR can be suppressed.

[0153] Alternatively, multiple holes 74 may not be provided on the tube 72 in the above embodiment.

[0154] Alternatively, the inner insertion tube portion 73 may not be provided on the tube 72 in the above embodiment. Furthermore, the inner insertion tube portion 73 may be configured to protrude from the first opening 39a toward the second space S2.

[0155] In the above embodiment, the muffler structure M may also omit the pipe 72. In this case, the first flow path 40 becomes a flow path through which refrigerant gas flows sequentially through the first space S1, the first small space ss1, the second space S2, the second small space ss2, the third space S3, the third small space ss3, and the fourth space S4. This increases the number of times expansion and contraction occur repeatedly in the first flow path 40, and because the flow path lengths L1 to L4 of the first space S1 to the fourth space S4 are different, the noise reduction effect can be improved.

[0156] In the above embodiments, the silencer structure M only needs to be configured such that the refrigerant gas flowing in the silencer chamber SR repeatedly expands and contracts, and the number and shape of the partition walls 37 are not limited. For example, in addition to the first partition walls 37b to the third partition walls 37d, partition walls can also be provided in the first flow path 40. In addition, the main partition wall 37a may not be configured to allow the refrigerant gas to flow in a U-shape.

[0157] The spacer wall 37 can be formed on the bearing support 27, or on both the bearing support 27 and the cover 31. When the spacer wall 37 is formed on both the bearing support 27 and the cover 31, a portion of each spacer wall 37 is formed on the bearing support 27, and the remaining portion is formed on the cover 31. Each spacer wall 37 is formed by mounting the cover 31 onto the bearing support 27.

[0158] In the above embodiment, pipe 72 can also be disposed in the first space S1. In this case, the inlet end of pipe 72 is connected to the inlet 44. The outlet end of pipe 72 is connected to the second space S2. The outer peripheral surface of pipe 72 is fixed at the first inner peripheral surface F1 (first opening 39a). The refrigerant gas ejected from the nozzle 26 flows sequentially through pipe 72, second space S2, second small space ss2, third space S3, third small space ss3, and fourth space S4. In this case, refrigerant noise can also be reduced by repeatedly contracting and expanding the refrigerant gas.

[0159] The embodiments and variations have been described above, but it should be understood that various changes can be made to the scheme and specific circumstances without departing from the spirit and scope of the claims. The embodiments and variations described above can also be appropriately combined and substituted as long as the function of the object of this disclosure is not affected. The terms "first," "second," etc., used above are only used to distinguish statements containing the above terms and are not intended to limit the number or order of the statements.

[0160] -Industry Applicability-

[0161] In summary, this disclosure is very useful for compressors.

[0162] - Symbol Explanation -

[0163] M silencer structure

[0164] S1 First Space (First Silencer Section, First Expansion Space)

[0165] S2 Second Space (Second Muffler Section, Second Expansion Space)

[0166] 8. Ejector pipe

[0167] 10 Compressors

[0168] 11. Chassis

[0169] 11a Opening

[0170] 18 drive shafts

[0171] 20 Compression Mechanism

[0172] 26. Injection outlet (compression chamber outlet)

[0173] 27. Bearing bracket (plate)

[0174] 31 Cover section

[0175] 37. Spacer

[0176] 37b First partition wall

[0177] 38 Ejection Flow Path

[0178] 41 Mainstream Road

[0179] 42 Secondary Flow Path

[0180] 43 Branch Flow Path

[0181] 72 tubes

Claims

1. A compressor, characterized in that: The compressor includes: Compression mechanism (20); A silencer structure (M) is arranged between the compression chamber outlet (26) of the compression mechanism (20) and the inflow end of the ejector pipe (8); Silencer (SR); and The oil separator body (50) has a separation space (51) for separating oil from the refrigerant. The muffler structure (M) consists of a first muffler section (S1) and a second muffler section (S2), which are connected in series via a first small space (SS1) to allow the refrigerant gas to repeatedly expand and contract. The first silencer section (S1) and the second silencer section (S2) are formed by a partition wall (37) disposed in the silencing chamber (SR). The first small space (ss1) is an opening (39a) provided in the partition wall (37), through which the first silencer section (S1) and the second silencer section (S2) are interconnected. The oil separator body (50) is disposed between the outlet (45) of the muffler structure (M) and the inlet end of the spray pipe (8).

2. The compressor according to claim 1, characterized in that: The muffler structure (M) is positioned closer to the compression chamber outlet (26) than closer to the inflow end of the ejector pipe (8) between the compression chamber outlet (26) and the ejector pipe (8).

3. The compressor according to claim 1 or 2, characterized in that: The refrigerant gas that is the object of the muffler structure (M) has an attenuation frequency of less than 3000 Hz or an attenuation of more than 10 dB.

4. The compressor according to claim 1 or 2, characterized in that: The refrigerant gas that is the object of the muffler structure (M) has an attenuation frequency of less than 2000 Hz or an attenuation of more than 20 dB.

5. The compressor according to claim 1 or 2, characterized in that: The muffler structure (M) has a first expansion space (S1) and a second expansion space (S2) with different volumes. The first expansion space (S1) is the first muffler section (S1). The second expansion space (S2) is the second muffler section (S2).

6. The compressor according to claim 5, characterized in that: The compressor also includes a housing (11), a plate (27), and a cover (31). The housing (11) has an opening (11a) formed on the discharge side of the compressor (10). The plate (27) is arranged inside the housing (11) and holds the shaft end of the drive shaft (18) located inside the compressor (10). The cover (31) is concave and is mounted on the housing (11) to seal the opening (11a), and forms an anechoic chamber (SR) between the cover (31) and the plate (27). The silencer structure (M) is disposed in the silencing chamber (SR).

7. The compressor according to claim 6, characterized in that: The first expansion space (S1) and the second expansion space (S2) are formed by the partition wall (37) disposed in the anechoic chamber (SR).

8. The compressor according to claim 7, characterized in that: The partition wall (37) is integral with the plate portion (27) or the cover portion (31).

9. The compressor according to claim 8, characterized in that: The partition wall (37) has a first partition wall (37b) that separates the first expansion space (S1) from the second expansion space (S2). A first opening (39a) is formed on the first partition wall (37b) to connect the first expansion space (S1) and the second expansion space (S2).

10. The compressor according to claim 9, characterized in that: The compressor also includes a pipe (72) which is connected to the outlet end of the muffler structure (M) and communicates with the inlet end of the ejector pipe (8).

11. The compressor according to claim 1 or 2, characterized in that: The silencer structure (M) includes a main flow path (41) and a secondary flow path (42). The main flow path (41) is the flow path through which refrigerant gas flows through the first silencer section (S1) and the second silencer section (S2). The secondary flow path (42) is a flow path through which refrigerant gas, after being diverted from the main flow path (41), rejoins the main flow path (41).

12. The compressor according to claim 1 or 2, characterized in that: The muffler structure (M) includes a main flow path (41) and branch flow paths (43). The main flow path (41) is the flow path through which refrigerant gas flows through the first silencer section (S1) and the second silencer section (S2). The branch flow path (43) is a flow path that branches off from the main flow path (41). The outlet end of the branch flow path (43) is closed.

13. The compressor according to claim 1 or 2, characterized in that: The flow path length of the silencer structure (M) is 50mm to 2000mm.

14. The compressor according to claim 1 or 2, characterized in that: The compressor also includes a sound-absorbing material, which is disposed on the inner wall of the first silencer section (S1) or the second silencer section (S2).

Images