CN114688024B

CN114688024B - Screw compressor

Info

Publication number: CN114688024B
Application number: CN202210221925.3A
Authority: CN
Inventors: 张海贤; 崔立祺; 奚晔
Original assignee: Johnson Controls Air Conditioning and Refrigeration Wuxi Co Ltd; Johnson Controls Tyco IP Holdings LLP
Current assignee: Johnson Controls Air Conditioning and Refrigeration Wuxi Co Ltd; Johnson Controls Tyco IP Holdings LLP
Priority date: 2022-03-09
Filing date: 2022-03-09
Publication date: 2024-04-05
Anticipated expiration: 2042-03-09
Also published as: WO2023172650A1; TW202348900A; CN114688024A

Abstract

The present application provides a screw compressor comprising: a housing, a pair of rotors, a pressure release passage and an adjusting means; the housing has a rotor cavity in which the pair of rotors are located, between whose teeth and the housing a compression cavity can be formed, the pair of rotors having a suction end and a discharge end, the discharge end having a discharge end face extending in a radial direction; the pressure release channel is provided with a pressure release channel inlet and a pressure release channel outlet, the pressure release channel inlet can be communicated with the compression containing cavity, and the pressure release channel outlet is communicated with the exhaust side of the compressor; the regulating device is movably mounted on the housing and configured to controllably open or close a pressure relief passage inlet to enable the compression pocket to be in communication with or disconnected from the pressure relief passage. The compressor in the present application is capable of regulating the gas pressure in the compression pockets.

Description

Screw compressor

Technical Field

The present application relates to compressors, and in particular to screw compressors having pressure regulating devices.

Background

Screw compressors are a common component in refrigeration units. The screw compressor utilizes the tooth space volumes of a pair of screw rotors to be meshed with each other, so that the change of the primitive volume consisting of tooth space is caused to complete the processes of gas suction, compression and discharge. A pair of mutually meshed screw rotors are arranged in parallel in a machine body of the screw compressor, and one end of each screw rotor is a suction end and communicated with a suction port of the machine body; the other end is an exhaust end which is communicated with an exhaust port of the machine body. As the screw rotor rotates, gas is sucked from the suction end and discharged from the discharge end after being compressed.

In the running process of the screw compressor, the actual working condition is not in accordance with the ideal setting working condition, and the screw compressor needs to reach the ideal setting working condition by a certain adjusting means.

Disclosure of Invention

During the operation of screw compression, there may be an over-compression condition, in which the compressor in the present application can automatically adjust the over-compression phenomenon of the compressor.

Screw compressor in this application includes: a housing having a rotor cavity; a pair of rotors in the rotor chamber, the pair of rotors having a suction end and a discharge end, the discharge end having a discharge end face extending in a radial direction, the pair of rotors being capable of forming a compression chamber between their teeth and the housing; a pressure relief passage provided in the housing, the pressure relief passage having a pressure relief passage inlet communicable with the compression volume and a pressure relief passage outlet communicable with a discharge side of the compressor; and an adjusting device movably mounted on the housing and configured to controllably open or close a pressure release passage inlet so that the compression volume can be communicated with or disconnected from the pressure release passage.

According to the screw compressor described above, the adjusting device is configured to: when the pressure in the compression volume of the screw compressor is greater than the pressure on the discharge side of the compressor, the regulating device opens the pressure relief passage inlet so that the compression volume communicates with the discharge side of the compressor; when the pressure in the compression volume of the screw compressor is less than the pressure on the discharge side of the compressor, the regulator closes the pressure relief passage inlet such that the compression volume is disconnected from the discharge side of the compressor.

According to the above screw compressor, the housing further includes a connection passage having a connection passage inlet near the discharge ends of the pair of rotors and capable of communicating with the compression volume, and a connection passage outlet communicating with the pressure release passage inlet.

According to the screw compressor, the shell further comprises an adjusting device accommodating cavity, and one end of the adjusting device accommodating cavity forms the connecting channel; the pressure release channel inlet is positioned on the side wall of the accommodating cavity of the adjusting device.

According to the screw compressor described above, the adjusting device has an outer side surface extending in the circumferential direction, which outer side surface can form a sealing side surface, and the adjusting device can be moved in the adjusting device housing chamber such that the sealing side surface can open or close the pressure release passage inlet.

According to the above screw compressor, the adjusting means has a head portion and a body portion, the head portion being larger in size than the body portion in a radial direction of the adjusting means, the seal side surface being located at a distal end of the body portion; the adjusting device accommodating chamber includes a first section in which the body is accommodated and a second section in which the head is accommodated, wherein the diameter of the second section is larger than that of the first section, the first section is closer to the pair of rotors than the second section, and the head is accommodated in the second section, and a seal is formed between the head and a side wall of the second section in a circumferential direction.

According to the screw compressor described above, the head has a distal end surface and a proximal end surface, the body is connected to the proximal end surface, the head divides the second section into a first region surrounded by the distal end surface and a side wall of the second section, and a second region surrounded by the proximal end surface, an outer surface of the body, and a side wall of the second section, the first region is in communication with an exhaust side of the compressor, the second region is in communication with the compression volume, and volumes of the first region and the second region vary with movement of the adjustment device.

According to the screw compressor described above, the housing further includes a pressure regulating passage having a pressure regulating passage inlet and a pressure regulating passage outlet, the pressure regulating passage outlet communicating with the second region, the pressure regulating passage inlet communicating with the compression volume, the pressure regulating passage inlet being closer to the suction ends of the pair of rotors than the connecting passage inlet in the axial direction of the pair of rotors.

According to the screw compressor described above, the housing has a housing mating surface disposed opposite to the exhaust end surfaces of the exhaust ends of the pair of rotors, the connection passage inlet is located on the housing mating surface and capable of coinciding with the exhaust end surfaces, the housing mating surface is provided with an exhaust chamber opening, and a certain distance is provided between the connection passage inlet and the exhaust chamber opening in a radial section.

According to the above screw compressor, the rotor chamber has a rotor chamber side wall, the pressure regulating passage inlet coincides with the rotor chamber side wall, and a certain distance is provided between the pressure regulating passage inlet and the exhaust end face in the axial direction of the pair of rotors.

The compressor in the present application has a regulating device, a pressure regulating passage, a pressure releasing passage and a pressure balancing passage. The adjusting device pushes the adjusting device to open or close the pressure release channel through the pressure change of the pressure adjusting channel and the pressure balancing channel so as to adjust the gas pressure in the compression containing cavity, thereby adjusting the over-compression phenomenon of the compressor. The adjusting device in the application does not need manual intervention. The adjusting device has simple structure and is easy to manufacture and maintain.

Drawings

FIG. 1A is a perspective view of a screw compressor of a first embodiment of the present application;

FIG. 1B is an exploded view of the screw compressor of FIG. 1A;

FIG. 1C is an axial cross-sectional view of the screw compressor of FIG. 1A taken along the line A-A and looking in the direction indicated by the arrow;

FIG. 2A is a perspective view of the rotor seat of FIG. 1B;

FIG. 2B is a side view of the rotor seat of FIG. 2A;

FIG. 2C is a cross-sectional view of the rotor seat of FIG. 2B taken along line B-B;

FIG. 3A is a perspective view of the exhaust seat of FIG. 1B;

FIG. 3B is a view of the exhaust seat of FIG. 3B from the exhaust end face;

FIG. 3C is a cross-sectional view of the exhaust seat of FIG. 3B taken along line C-C;

FIG. 4 is a perspective view of the adjustment device of FIG. 1B;

FIG. 5A is a side view of the screw compressor of FIG. 1A;

FIG. 5B is a cross-sectional view of the screw compressor of FIG. 5A taken along line D-D;

FIG. 5C is a cross-sectional view of the screw compressor of FIG. 5A taken along line F-F;

FIG. 5D is another cross-sectional view of the screw compressor of FIG. 5A taken along line D-D;

FIG. 5E is another cross-sectional view of the screw compressor of FIG. 5A taken along line F-F;

FIG. 6 is a cross-sectional view of a rotor mount of a second embodiment of the screw compressor of the present application;

FIG. 7A is a side view of a second embodiment of a screw compressor of the present application;

FIG. 7B is a cross-sectional view of the screw compressor of FIG. 7A taken along line G-G;

fig. 7C is another cross-sectional view of the screw compressor of fig. 7A taken along line G-G.

Detailed Description

Various embodiments of the present application are described below with reference to the accompanying drawings, which form a part hereof. It will be understood that, although terms indicating directions such as "front", "rear", "upper", "lower", "left", "right", "inner", "outer", "top", "bottom", "forward", "reverse", "proximal", "distal", "transverse", "longitudinal", etc. are used in this application to describe various example structural parts and elements of this application, these terms are used herein for convenience of description only and are determined based on the example orientations shown in the drawings. Because the embodiments disclosed herein may be arranged in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting.

Fig. 1A is a perspective view of a screw compressor according to an embodiment of the present application, fig. 1B is an exploded view of the screw compressor of fig. 1A, and fig. 1C is an axial sectional view of the screw compressor of fig. 1A taken along the line A-A and viewed in the direction indicated by the arrow. Fig. 1A-1C show part of the components of a screw compressor. As shown in fig. 1A to 1C, the screw compressor includes a housing 101, a pair of screw rotors 110, and adjustment devices 108 and 109. Wherein the housing 101 includes a rotor seat 131 and an exhaust seat 132.

The rotor housing 131 has a rotor cavity 105 for receiving a pair of screw rotors 110. The rotor housing 131 has a discharge chamber 180, and the discharge chamber 180 communicates with a discharge port 181 of the compressor.

The screw rotor 110 includes a pair of intermeshing male and female rotors 121 and 122, and the male and female rotors 121 and 122 can be driven to rotate. Screw rotor 110 includes tooth 160, and shaft portions 161 and 162 connected to both ends of tooth 160, respectively. At the teeth 160 of the screw rotor 110, the male rotor 121 has a plurality of helical teeth, grooves are formed between adjacent teeth, and the female rotor 122 also has a plurality of helical teeth, grooves are also formed between adjacent teeth. The passing teeth and corresponding grooves of the male rotor 121 and the female rotor 122 constitute an intermeshing structure and form compression pockets 150 together with the housing 101.

In the axial direction of the screw rotor 110, the teeth 160 of the screw rotor 110 have a suction end 112 and a discharge end 113. Gas is drawn into the compression pockets 150 at the suction end 112 and gradually moves toward the discharge end 113 as the screw rotor 110 rotates. At the same time, the volume of the compression pocket 150 is gradually reduced as the screw rotor 110 rotates, and the gas in the compression pocket 150 is gradually compressed. The compressed gas enters the compressor discharge chamber 180 from the discharge end 113 and is then discharged from the compressor discharge port 181. The exhaust end 113 has an exhaust end face 118.

Fig. 2A is a perspective view of the rotor seat of fig. 1B, fig. 2B is a side view of the rotor seat of fig. 2A, and fig. 2C is a cross-sectional view of the rotor seat of fig. 2B taken along line B-B. As shown in fig. 2A-2C, the rotor seat includes a front end 211 and a rear end 212. The front end 211 is adjacent the suction end 112 of the screw rotor 110 and the rear end 212 is adjacent the discharge end 113 of the screw rotor 110. The rear end 212 is connected to the exhaust seat 132, and the rear end 212 has a rear end face 207. Rotor pocket 105 extends through rear end face 207 forming rotor pocket opening 215. Rotor pocket 105 has rotor pocket sidewalls 188, and rotor pocket sidewalls 188 are capable of forming a seal with teeth 160 of a pair of screw rotors. The rotor housing 131 has a rotor housing pressure regulating passage 240. The rotor seat pressure adjustment channel 240 has an inlet 241 and an outlet 242, wherein the inlet 241 is located on the rotor pocket side wall 188 and is spaced from the rear end face 207. The outlet 242 is located on the rear end face 207.

The distance between the inlet 241 and the rear end face 207 may be adjusted according to the specific configuration requirements of the screw compressor. In one embodiment of the present application, the distance between the inlet 241 and the rear end face 207 is less than half the length of the teeth 160 of the screw rotor 110 in the axial direction.

Fig. 3A is a perspective view of the exhaust seat of fig. 1B, fig. 3B is a view of the exhaust seat of fig. 3B from an exhaust end face, and fig. 3C is a sectional view of the exhaust seat of fig. 3B taken along line C-C.

As shown in fig. 3A-3C, the exhaust seat 132 has a first end 311 and a second end 312, the first end 311 being connected to the rotor seat 131. The end surface of the first end 311 forms a housing engagement surface 341, and the housing engagement surface 341 engages the rear end surface 207 of the rotor housing 131.

The exhaust seat 132 has rotor shaft pockets 361 and 362, an exhaust chamber 180, regulator pockets 310 and 320, and pressure relief passages 328 and 329.

Rotor shaft receptacles 361 and 362 are for receiving the shaft of screw rotor 110, and rotor shaft receptacles 361 and 362 form rotor shaft openings 371 and 372 on housing mating surface 341. The vent chamber 180 forms a vent chamber opening 366 in the housing mating surface 341. The adjustment device receptacles 310 and 320 form adjustment device receptacle openings 367 and 368 on the housing mating face 341. Wherein the vent lumen opening 366 is spaced from the regulator lumen openings 367 and 368. The pressure relief passage 328 communicates the regulator pocket 320 with the vent pocket 180.

The housing mating surface 341 has a rotor projection area 382 thereon, and the rotor projection area 382 is a projection area formed on the housing mating surface 341 along the axial direction during rotation of the pair of screw rotors 110. The rotor projection area 382 is generally "8" shaped and is disposed about the rotor shaft openings 371 and 372.

During rotation of the pair of screw rotors 110, the extent swept by the exhaust end face 118 at the housing mating face 341 is within the range defined by the rotor projection region 382. The rotor projection region 382 has a sealing region 326 and first and second open regions 337, 338 and 339. Wherein the overlapping portion of the exhaust chamber opening 366 and the rotor projection area 382 forms a first opening area 337, the overlapping portion of the regulator pocket openings 367 and 368 and the rotor projection area 382 forms second opening areas 338 and 339, and the remaining portion forms the sealing area 326. The second opening areas 338 and 339 are each located downstream of the corresponding screw rotor in the direction of rotation relative to the first opening area 337. That is, during rotation, the screw rotor passes through the second open areas 338 and 339 before reaching the first open area 337.

The sealing area 326 can seal the end of the compression pockets 150 such that the compression pockets 150 can form a sealed space. During rotation of the pair of screw rotors 110, when the ends of the compression pockets 150 are aligned with the sealing region 326, the compression pockets 150 are disconnected from the discharge pockets 180, and the refrigerant gas in the compression pockets 150 can be compressed; when the end of the compression volume 150 is aligned or partially aligned with the first opening region 337, the compression volume 150 can communicate with the vent chamber 180, and the gas in the compression volume 150 can be vented; the compression pockets 150 selectively communicate with or disconnect from the pressure relief passages 328 and 329 when the ends of the compression pockets 150 are aligned or partially aligned with the second open areas 338 and 339. The selective communication of compression pockets 150 with pressure relief passages 328 and 329 will be described in detail below. The structure between the regulator pockets 310 and 320 and between the pressure relief passages 328 and 329 in this application are similar and are differently located, and the structure of the regulator pocket 320 and the exhaust seat pressure relief passage 329 will be described below as an example.

As shown in fig. 3C, the regulator pocket 320 is formed by an extension of the regulator pocket opening 368 toward the interior of the exhaust seat. The distal end of the adjustment device receptacle 320 (i.e., the end remote from the adjustment device receptacle opening 367) has a bottom wall 383. The regulator pocket 320 has a first section 321 and a second section 322, the first section 321 being adjacent the regulator pocket opening 367 and the second section 322 being adjacent the bottom wall 383. The diameter of second section 322 is greater than the diameter of first section 321 such that a step surface 335 is formed at the junction of first section 321 and second section 322. The adjustment device receptacle 320 is shaped to cooperate with the adjustment device 109 such that the adjustment device 109 is movable within the adjustment device receptacle 320.

In this application, to facilitate assembly of the adjustment devices 108 and 109, the exhaust seat 132 includes separable sleeves 357 and 358. The sleeves 357 and 358 are fixedly connected to the exhaust seat body after the adjustment devices 108 and 109 are installed in the exhaust seat body. Sleeves 357 and 358 are generally cylindrical, with the sidewalls of sleeves 357 and 358 surrounding first section 321. The sidewalls of sleeves 357 and 358 have openings to form the connecting channel outlets. The stepped surface 335 is formed by an end surface of one end of the sleeve 358.

The regulator receptacle 320 has a connecting passage 398 at one end, the connecting passage 398 being formed by a portion of the first section 321 of the regulator receptacle 320 adjacent the regulator receptacle opening 367. That is, the connecting passage 398 is one of the first sections 321. In this embodiment, the connecting channel 398 is the portion of the regulator housing 320 located below the dashed line in fig. 3C. The connecting channel 398 has a connecting channel inlet 396 and a connecting channel outlet 397, the connecting channel inlet 396 being formed by a portion of the regulator pocket opening 368, the connecting channel inlet 396 coinciding with the second opening region 338. The connecting channel outlet 397 is located on the side wall of the first section 321 of the regulator housing 320.

The exhaust seat pressure relief channel 329 has an inlet 316 and an outlet 317, wherein the inlet 316 is located on a side wall of the first section 321 of the regulator pocket 320 and coincides with the connecting channel outlet 397. The connection passage outlet 397 is located on a side wall of the exhaust chamber 180 and communicates with the exhaust chamber 180.

The exhaust seat 132 further includes an exhaust seat pressure adjustment passage 334 and a pressure balance passage 355. An inlet 332 of the exhaust seat pressure adjustment passage 334 communicates with the rotor seat pressure adjustment passage outlet 242 and an outlet 333 of the exhaust seat pressure adjustment passage 334 communicates with the second section 322 of the adjustment device receptacle 320. An outlet 333 of the exhaust seat pressure regulator passage 334 is located on a side wall of the second section 322 and is proximate to the first section 321.

A first end of the pressure equalization channel 355 communicates with the second section 322 of the regulator pocket 310 and a second end of the pressure equalization channel 355 communicates with the exhaust pocket 180. The junction of the first end of the pressure equalization channel 355 with the regulator housing 310 is located on the sidewall of the regulator housing 310 and adjacent to the bottom wall 383 of the regulator housing 310. In another embodiment of the present application, the connection is located on the bottom wall 383 of the regulator housing 310.

Fig. 4 is a perspective view of the adjustment device 109 of fig. 1B, as shown in fig. 4, the adjustment device 109 is a piston having a head 411 and a body 412. Wherein the diameter of the head 411 is larger than the diameter of the body portion 412, the outer diameter of the head 411 is matched to the inner diameter of the second section 322 of the adjusting means housing 320, the outer diameter of the body portion 412 is matched to the inner diameter of the first section 321 of the adjusting means housing 320, the head 411 is accommodated in the second section 322, and the body portion 412 is accommodated in the first section 321. Wherein in the axial direction the second section 322 of the adjustment device receptacle 320 is longer than the length of the head 411 of the adjustment device 109, and the first section 321 of the adjustment device receptacle 320 is shorter than the length of the body 412 of the adjustment device 109, such that the adjustment device 109 is movable in the axial direction within a certain range in the adjustment device receptacle 320. The head 411 has a distal surface 441 and a proximal surface 442, and the body 412 is connected to the proximal surface 442.

The body 412 has an outer side 401 extending in the circumferential direction, which outer side 401 can form a sealing side 423, which sealing side 423 can open or close the pressure release channel inlet 316 when the adjusting device 109 is moved in the adjusting device receptacle 320. The distal end of the body 412 (i.e., the end remote from the head 411) has an adjustment device sealing end face 455. The shape of the regulator sealing end face 455 matches the shape of the regulator cavity opening 368 such that the regulator sealing end face 455 is capable of sealing the regulator cavity opening 368.

A sealing ring may be provided around the circumferential outer side of the head 411 to enhance the seal between the head 411 and the side wall of the second section 322.

Fig. 5A is a side view of the screw compressor of fig. 1A, fig. 5B is a cross-sectional view of the screw compressor of fig. 5A taken along line D-D, fig. 5C is a cross-sectional view of the screw compressor of fig. 5A taken along line F-F, fig. 5D is another cross-sectional view of the screw compressor of fig. 5A taken along line D-D, fig. 5E is another cross-sectional view of the screw compressor of fig. 5A taken along line F-F, fig. 5B and 5C show the state where the pressure relief passage is in the closed position, and fig. 5D and 5E show the state where the pressure relief passage is in the open position.

As shown in fig. 5B, the length of the body 412 of the adjustment device 109 is greater than the length of the first section 321 of the adjustment device housing 320, and the diameter of the body 412 is less than the diameter of the second section 322 of the adjustment device housing 320. The head 411 is spaced from the step surface 335. The head 411 divides the second section 322 into a first region 551, the first region 551 being surrounded by the distal surface 441 and the side wall of the second section 322, and a second region 552, the second region 552 being surrounded by the proximal surface 442, the outer surface of the body 412, and the side wall of the second section 322, the first region 551 communicating with the discharge side of the compressor, the second region 552 communicating with the compression pocket 150, the volumes of the first and second regions 551 and 552 varying with movement of the adjustment device 109.

The housing 101 has a pressure regulating passage 540, the pressure regulating passage 540 being formed by connecting the rotor seat pressure regulating passage 240 and the pressure regulating passage 334. The pressure regulating passage inlet 541 is formed by the rotor seat pressure regulating passage inlet 241, and the pressure regulating passage outlet 542 is formed by the outlet 333 of the exhaust seat pressure regulating passage 334. The outlet 542 of the pressure regulating channel is located on the side wall of the second region 552, and the pressure balancing channel 355 communicates with the first region 551. The gas pressure in the second region 552 is equal to the gas pressure at the pressure adjustment passage inlet 541, and the gas pressure in the first region 551 is equal to the pressure of the gas in the pressure exhaust chamber 180. When the gas pressure in the vent chamber 180 is greater than the gas pressure at the pressure adjustment passage inlet 541, the adjustment device is pressurized to the left as viewed in FIG. 5B, enters the connecting passage 398 and closes the pressure relief passage. When the end of the compression pocket 150 of the screw rotor 110 communicates with the discharge pocket opening 366, the gas in the compression pocket is discharged. When the gas pressure in the vent chamber 180 is less than the gas pressure at the pressure adjustment passage inlet 541, the adjustment device is subjected to a pressure to the right as viewed in fig. 5B, exits the connecting passage 398 and opens the pressure relief passage. When the end of the compression pocket 150 is first rotated into communication with the regulator pocket opening 368 and not rotated to the vent pocket opening 366, the gas in the compression pocket is discharged in advance through the pressure release passage 329.

As shown in fig. 5B and 5C, when the pressure release passage is in the closed position, the adjustment device 109 abuts against the rotor seat rear end face 207, and at this time, the body 412 of the adjustment device 109 is positioned in the connection passage 398 and fills the connection passage 398, so that the connection passage 398 is closed. The regulator pocket opening 368 is closed by the regulator sealing end face 455 and the inlet 316 of the pressure relief channel 329 is closed by the sealing side face 423. When the pressure relief passage is in the closed position, the rotor volume 105 needs to be rotated to a position in communication with the vent chamber opening 366, and the gas in the rotor volume 105 is vented to the vent chamber 180.

As shown in fig. 5D and 5E, when the pressure release passage is in the open position, the adjustment device 109 is moved away from the rotor seat rear end face 207, and at this time, the body 412 of the adjustment device 109 is moved away from the connection passage 398, so that the connection passage 398 is opened. The regulator pocket opening 368 communicates with the compression pocket 150 and the inlet 316 of the pressure relief passage 329 communicates with the connecting passage 398. When the pressure relief channel is in the open position, the gas in the rotor pocket 105 may be vented to the vent chamber 180 through the pressure relief channel 329 when the compression pocket 150 is in communication with the regulator pocket opening 368 and does not reach the vent pocket opening 366. That is, when the pressure relief passage is in the open position, the gas in the compression volume 150 is discharged in advance, thereby reducing the pressure in the compression volume 150, avoiding over-compression in which the pressure in the compression volume 150 is greater than the discharge-side pressure.

The adjustment device 109 is automatically adjusted by pressure changes in the pressure adjustment channel 540 and the pressure equalization channel 355 without manual intervention. The adjusting device 109 is simple in structure and easy to manufacture and maintain.

Fig. 6 is a sectional view of a rotor seat of a second embodiment of the screw compressor of the present application, fig. 7A is a side view of the second embodiment of the screw compressor of the present application, fig. 7B is a sectional view of the screw compressor of fig. 7A taken along line G-G, fig. 7C is another sectional view of the screw compressor of fig. 7A taken along line G-G, fig. 7B shows a state in which the pressure release passage is in a closed position, and fig. 7C shows a state in which the pressure release passage is in an open position.

As shown in fig. 6, the rotor seat has a regulator pocket 610, a pressure regulating passage 640, a pressure relief passage 629, and a pressure balancing passage 655. The adjustment device receptacle 610 has an adjustment device receptacle opening 668, the adjustment device receptacle opening 668 being located on a side wall of the rotor receptacle. The regulator pocket 610 has a first segment 611, a second segment 612, and a third segment 613. The diameters of the first, second and third sections 611, 612 and 613 increase in order. The inlet 641 of the pressure adjustment passage 640 communicates with the compression pockets, and the inlet 641 of the pressure adjustment passage 640 is closer to the suction ends of a pair of rotors than the regulator pocket 610. As shown in fig. 6, the inlet 641 of the pressure adjustment passage 640 is located on the left side of the adjustment device receptacle 610. The outlet of the pressure relief passage 629 communicates with the exhaust chamber and the inlet 616 of the pressure relief passage 629 communicates with the first segment 611 and is located on the side wall of the first segment 611. The inlet 616 of the pressure relief passage 629 is spaced from the side wall of the rotor chamber. One end of the pressure equalization passageway 655 communicates with the second segment 612 and the other end communicates with the exhaust chamber. The first section of the adjustment device receptacle 610 defines a connecting passage 698 at an end of the adjustment device receptacle adjacent the rotor receptacle. The connection passage 698 communicates with the pressure release passage 629. The adjustment device receptacle 610 has an adjustment device receptacle opening 668.

The embodiment shown in fig. 6-7C is similar to the embodiment shown in fig. 1A, except that the adjustment device 709 is disposed in the rotor mount 131 and is disposed in a direction generally perpendicular to the pair of screw rotors 110.

As shown in fig. 7B, 7C, the adjustment device 709 has a body 712, a head 711 and an extension 713, the head 711 being located in the second section 612 of the adjustment device receptacle 610, the body 712 being located in the first section 611 of the adjustment device receptacle 610. The head has a proximal surface 742 and a distal surface 741, the body is connected to the proximal surface 742 and the extension 713 is connected to the distal surface 741. The extension 713 is coupled to the head 711 to facilitate assembly and retention. The diameters of the extension 713 and the body 712 are each smaller than the diameter of the head 711. The length of the body 712 of the adjustment means 709 is greater than the length of the first section 611 of the adjustment means housing 610 and the diameter of the body 712 is smaller than the diameter of the second section 612 of the adjustment means housing 610. The head 711 divides the second section 612 into a first region 751 surrounded by the head distal end surface 741, the outer wall of the extension 713 and the side wall of the second section 612, and a second region 752 surrounded by the head proximal end surface 742, the outer surface of the body 712 and the side wall of the second section 612, the first region 751 communicating with the discharge side of the compressor through the pressure regulating passage 640, the second region 752 communicating with the compression volume 750 through the pressure balancing passage 655, the volumes of the first and second regions 751 and 752 varying with the movement of the regulating device 109.

As shown in fig. 7B, when the pressure relief channel is in the closed position, the end face of the body 712 of the adjustment device 709 is flush with the adjustment device receptacle opening 668, at which time the body 712 of the adjustment device 709 is positioned in the connection channel 698 and fills the connection channel 698 such that the connection channel 698 is closed. The adjusting device receptacle opening 668 is closed by an end face of the body 712 of the adjusting device 709, and the inlet 616 of the pressure release channel 629 is closed by a side face of the body of the adjusting device 709. When the pressure relief passage is in the closed position, the compression pockets need to be rotated to a position in communication with the discharge pocket openings, and the gas in the compression pockets can be discharged to the discharge pocket 180.

As shown in fig. 7C, when the pressure relief passage is in the open position, the adjustment device 709 exits the adjustment device receptacle opening 668, at which point the body 712 of the adjustment device 709 exits the connection passage 698, whereby the connection passage 698 is opened and the inlet 616 of the pressure relief passage 629 communicates with the compression receptacle through the connection passage 698. When the pressure relief passage is in the open position, the compression pockets are in communication with the regulator pocket opening 668 and do not reach the vent pocket opening, the gas in the rotor pockets can be vented to the vent pocket through the pressure relief passage. That is, when the pressure release passage is in the open position, the gas in the compression volume is discharged in advance, thereby reducing the pressure in the compression volume, avoiding overcompression in which the pressure in the compression volume is greater than the discharge side pressure.

The embodiment shown in fig. 6-7C can achieve the same technical effects as the embodiment shown in fig. 1A.

While the present disclosure has been described in conjunction with the examples of embodiments outlined above, various alternatives, modifications, variations, improvements, and/or substantial equivalents, whether known or that are or may be presently or later be envisioned, may be apparent to those of ordinary skill in the art. Further, the technical effects and/or technical problems described in the present specification are exemplary rather than limiting; the disclosure in this specification may be used to solve other technical problems and to have other technical effects and/or may solve other technical problems. Accordingly, the examples of embodiments of the disclosure as set forth above are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit or scope of the disclosure. Accordingly, the present disclosure is intended to embrace all known or earlier developed alternatives, modifications, variations, improvements and/or substantial equivalents.

Claims

1. A screw compressor, comprising:

-a housing (101), the housing (101) having a rotor volume (105);

-a pair of rotors (110), the pair of rotors (110) being located in the rotor volume (105), compression volumes (150) being formable between teeth of the pair of rotors (110) and the housing (101), the pair of rotors (110) having a suction end (112) and a discharge end (113), the discharge end (113) having a discharge end face (118) extending in a radial direction;

a pressure relief passage provided in the housing (101), the pressure relief passage having a pressure relief passage inlet and a pressure relief passage outlet, the pressure relief passage outlet communicating with a compressor discharge side of the screw compressor;

an adjustment device movably mounted on the housing (101) and configured to controllably open or close the pressure relief passage inlet to enable the compression pocket (150) to be in communication with or disconnected from the pressure relief passage;

the regulating device containing cavity is arranged in the regulating device containing cavity and divides the regulating device containing cavity into a first area and a second area, the first area is communicated with the exhaust side of the compressor, and the regulating device containing cavity can be used for communicating the compression containing cavity (150) with the inlet of the pressure release channel; and

a pressure regulating passage configured to communicate the compression volume (150) with the second region of the regulator volume; wherein, in the axial direction of the pair of rotors (110), the junction of the pressure regulating passage and the compression volume (150) is closer to the suction end of the pair of rotors than the junction of the regulator volume and the compression volume (150), the regulator is configured to: when the pressure in the compression volume (150) of the screw compressor is greater than the pressure on the compressor discharge side, the regulating device opens the pressure relief passage inlet so that the compression volume communicates with the compressor discharge side; when the pressure in the compression volume (150) of the screw compressor is less than the pressure on the compressor discharge side, the regulator closes the pressure relief passage inlet such that the compression volume is disconnected from the compressor discharge side.

2. The screw compressor of claim 1, wherein:

the housing (101) further includes a connecting channel having a connecting channel inlet proximate the discharge ends of the pair of rotors and capable of communicating with the compression pockets (150), and a connecting channel outlet in communication with the pressure relief channel inlet.

3. The screw compressor of claim 2, wherein:

one end of the accommodating cavity of the adjusting device forms the connecting channel; the pressure release channel inlet is positioned on the side wall of the accommodating cavity of the adjusting device.

4. A screw compressor according to claim 3, wherein:

the adjusting device has an outer side extending in the circumferential direction, which outer side can form a sealing side, which adjusting device can be moved in the adjusting device receptacle such that the sealing side can open or close the pressure release channel inlet.

5. The screw compressor of claim 4, wherein:

the adjusting device has a head and a body, the head being larger in size than the body in the radial direction of the adjusting device, the sealing side being located at the distal end of the body;

the adjusting device accommodating chamber comprises a first section and a second section, wherein the diameter of the second section is larger than that of the first section, the first section is closer to the pair of rotors than the second section, the body is accommodated in the first section, the head is accommodated in the second section, and a seal is formed between the head and the side wall of the second section in the circumferential direction.

6. The screw compressor of claim 5, wherein:

the head has a distal end surface and a proximal end surface, the body is connected with the proximal end surface, the head divides the second section into a first area and a second area, the first area is defined by the distal end surface and the side wall of the second section, the second area is defined by the proximal end surface, the outer surface of the body and the side wall of the second section, the first area is communicated with the exhaust side of the compressor, the second area is communicated with the compression volume, and the volumes of the first area and the second area change along with the movement of the regulating device.

7. The screw compressor of claim 6, wherein:

the pressure regulating passage has a pressure regulating passage inlet and a pressure regulating passage outlet, the pressure regulating passage outlet being in communication with the second region, the pressure regulating passage inlet being in communication with the compression volume, the pressure regulating passage inlet being closer to the suction ends of the pair of rotors than the connecting passage inlet in an axial direction of the pair of rotors.

8. The screw compressor of claim 2, wherein:

the shell is provided with a shell matching surface which is arranged opposite to the exhaust end surfaces of the exhaust ends of the pair of rotors, the connecting channel inlet is positioned on the shell matching surface and can be overlapped with the exhaust end surfaces, the shell matching surface is provided with an exhaust cavity opening, and a certain distance is reserved between the connecting channel inlet and the exhaust cavity opening on the radial section.

9. The screw compressor of claim 7, wherein:

the rotor cavity is provided with a rotor cavity side wall, the pressure regulating channel inlet is overlapped with the rotor cavity side wall, and a certain distance is arranged between the pressure regulating channel inlet and the exhaust end face in the axial direction of the pair of rotors.