CN218760417U

CN218760417U - Screw compressor with adjustable internal volume ratio

Info

Publication number: CN218760417U
Application number: CN202222835622.9U
Authority: CN
Inventors: 钟仁志; 袁军; 林晓健
Original assignee: Xinlei Compressor Co Ltd
Current assignee: Xinlei Compressor Co Ltd
Priority date: 2022-10-25
Filing date: 2022-10-25
Publication date: 2023-03-28
Anticipated expiration: 2032-10-25

Abstract

The utility model belongs to the technical field of the compressor and specifically relates to an interior volume ratio adjustable screw compressor, including compression mechanism, compression mechanism includes: the air compressor comprises a shell, a male rotor and a female rotor, wherein the male rotor and the female rotor are arranged in the shell and are meshed with each other, a compression cavity for compressing air is formed between the male rotor and the female rotor in a matching way, the compression cavity is provided with an air suction end for air to enter and an air exhaust end for air to exhaust, a slide valve is also arranged in the shell and is closely adjacent to one side of the male rotor and the female rotor and is positioned at the side close to the air exhaust end, a slide valve air exhaust port is arranged at the first end of the slide valve and is close to the air exhaust end, and the slide valve air exhaust port is communicated with the air exhaust end and the air exhaust cavity of the shell; the second end of the slide valve is provided with a pressure adjusting cavity, the pressure adjusting cavity is internally provided with a driving device, and the driving device drives the slide valve to move along the axial direction of the male rotor and the female rotor by changing the pressure of the pressure adjusting cavity so as to change the effective opening size of the exhaust end and adjust the internal volume ratio.

Description

Screw compressor with adjustable internal volume ratio

Technical Field

The utility model belongs to the technical field of the compressor and specifically relates to an interior volume ratio adjustable screw compressor.

Background

The internal volume ratio is an important parameter of the screw compressor and is closely related to the design condition and the actual condition of the screw compressor. Due to the change of the actual working condition, the pressure of the screw compressor after the compression is finished is often inconsistent with the pressure in the exhaust cavity, so that the constant volume compression or the constant volume expansion is caused, and further, the additional power consumption is increased. Therefore, the internal volume ratio needs to be adjusted, so that the pressure after compression is equal to the pressure in the exhaust cavity, different working conditions are adapted, energy consumption is reduced, and the operation condition is improved.

SUMMERY OF THE UTILITY MODEL

In order to solve the problem, the utility model aims at providing an interior volume ratio adjustable screw compressor adjusts the interior volume ratio through the effective opening size that changes the exhaust end to adapt to different operating modes.

For the purpose of the utility model, the following technical scheme is adopted for implementation:

a screw compressor with an adjustable internal volume ratio, comprising a compression mechanism, the compression mechanism comprising: the air compressor comprises a shell, a male rotor and a female rotor, wherein the male rotor and the female rotor are arranged in the shell and meshed with each other, a compression cavity for compressing air is formed between the male rotor and the female rotor in a matching manner, the compression cavity is provided with an air suction end for air to enter and an air exhaust end for air to exhaust, a slide valve is further arranged in the shell and is closely adjacent to one side of the male rotor and one side of the female rotor, the slide valve is positioned on the side close to the air exhaust end, a slide valve air exhaust port is arranged at the first end of the slide valve and is close to the air exhaust end, and the slide valve air exhaust port is communicated with the air exhaust end and the air exhaust cavity of the shell; the second end of the slide valve is provided with a pressure adjusting cavity, the pressure adjusting cavity is internally provided with a driving device, and the driving device drives the slide valve to move along the axial direction of the male rotor and the female rotor by changing the pressure of the pressure adjusting cavity so as to change the effective opening size of the exhaust end and adjust the internal volume ratio.

Preferably, the sides of the slide valves facing the male and female rotors are working faces, the profiles of the working faces are adapted to the profiles of the male and female rotors, and the working faces are arranged on the peripheries of the male and female rotors in the immediate vicinity; the slide valve air outlet is positioned at the end part of the working surface, and the opening size of the slide valve air outlet is gradually increased from inside to outside in the axial direction of the slide valve.

Preferably, the inner end of the spool valve exhaust port is connected to the outer end of the working surface, the outer end of the spool valve exhaust port extends axially outward to the end of the spool valve, and the outer end of the spool valve exhaust port gradually flares radially outward.

Preferably, the cross section of the slide valve exhaust port is V-shaped, and the opening of the V-shape faces to the outer end.

Preferably, a first blocking portion is arranged at the first end of the sliding valve, a second blocking portion is arranged on the shell, the second blocking portion is located at one end of the sliding valve, and the second blocking portion limits the first blocking portion.

Preferably, a third blocking portion extending radially outwards is arranged at the second end of the slide valve, a fourth blocking portion is arranged in the shell, the fourth blocking portion is located at one end of the male rotor and the female rotor, the fourth blocking portion and the third blocking portion are at least partially overlapped in the axial direction, and the fourth blocking portion blocks the third blocking portion at the outer ends of the male rotor and the female rotor.

Preferably, the driving device comprises a hydraulic passage, hydraulic oil arranged in the hydraulic passage, and a control valve for controlling the flow of the hydraulic oil, the hydraulic passage comprises an oil outlet hole and an oil return hole, the oil outlet hole and the oil return hole are both positioned in the pressure adjusting cavity, the oil return hole is positioned on the lower surface of the pressure adjusting cavity, and the control valve controls the flow of the hydraulic oil in the oil outlet hole and the oil return hole to adjust the pressure of the pressure adjusting cavity.

Preferably, the oil outlet is relatively close to the outer end of the pressure regulating cavity, and the oil return hole is relatively close to the inner end of the pressure regulating cavity; the oil return holes are arranged in plurality and distributed along the axial direction of the pressure adjusting cavity.

Preferably, the compression mechanism comprises a low-pressure stage compression mechanism and a high-pressure stage compression mechanism which are communicated with each other, and compressed air output by the low-pressure stage compression mechanism is used as an air source at the suction side of the high-pressure stage compression mechanism; the low-pressure stage compression structure and the high-pressure stage compression structure are respectively provided with a low-pressure stage motor and a low-pressure stage motor, and the low-pressure stage motor respectively drive the corresponding male rotor and the female rotor to rotate.

To sum up, the beneficial effects of the utility model are that: the stepless regulation of the internal volume ratio is realized by adjusting the length of the slide valve matched with the rotor, the requirement of the internal volume ratio equality is met in real time, and the compressor is enabled to run under the minimum power. In addition, the two motors are arranged to independently control the low-pressure stage compression mechanism and the high-pressure stage compression mechanism, the air quantity of the low-pressure stage and the air quantity of the high-pressure stage can be adjusted in a stepless mode, the external pressure ratio is adjusted, and the compressor is combined with the slide valve to operate at the best energy-saving point.

Drawings

Fig. 1 is a perspective view of a screw compressor.

Fig. 2 is a plan view of the screw compressor.

Fig. 3 isbase:Sub>A cross-sectional view taken atbase:Sub>A-base:Sub>A in fig. 2.

Fig. 4 is a partially enlarged view of fig. 3 at B.

Fig. 5 is an exploded view of one perspective of the low pressure stage compression mechanism.

Fig. 6 is an exploded view of another perspective of the low pressure stage compression mechanism.

Fig. 7 is a perspective view of the spool valve.

Fig. 8 is a side view of a low pressure stage compression mechanism.

Fig. 9 is a side view of the housing.

Fig. 10 is a cross-sectional view taken at C-C in fig. 9.

Detailed Description

Fig. 1 shows a perspective view of a screw compressor including a compression mechanism for compressing air, which in the present embodiment includes a low-pressure stage compression mechanism 100 and a high-pressure stage compression mechanism 200. In other embodiments, only one compression mechanism may be provided, or a greater number of compression mechanisms may be provided, as desired.

As shown in fig. 1, the low-pressure stage compression mechanism 100 is located on the left side, and the high-pressure stage compression mechanism 200 is located on the right side, and they are communicated with each other so that the gas flow can flow from left to right inside. The low-pressure stage compression mechanism 100 is provided with an air inlet 101, the high-pressure stage compression mechanism 200 is provided with an air outlet 201, and the air inlet 101 and the air outlet 201 are provided with valves which are common in compressors such as a shut-off valve, a check valve and a filter valve, and detailed structures are not repeated herein.

When the compressor works, air enters the low-pressure stage compression mechanism 100 from the air inlet 101, the low-pressure stage compression mechanism 100 compresses the air for the first time and forms first compressed air, then the first compressed air flows to the right into the high-pressure stage compression mechanism 200, the high-pressure stage compression mechanism 200 compresses the first compressed air and forms second compressed air, and the second compressed air is discharged from the air outlet 201.

The specific structure of the compression mechanism will be exemplified below with reference to the low-pressure stage compression mechanism 100, and the high-pressure stage compression mechanism 200 is disposed with reference to the low-pressure stage compression mechanism 100.

As shown in fig. 3, the compression mechanism includes a housing 300, an intake passage 301 communicating with the intake port 101 is provided at the top of the housing 300, a pair of rotors is provided inside the housing 300, the rotors are engaged with each other and form a compression chamber 310 for compressing air, an upper portion of the compression chamber 310 is a suction end 311, a lower portion of the compression chamber 310 is a discharge end 312, and the suction end 311 is relatively close to the left side of the housing 300 and the discharge end 312 is relatively close to the right side of the housing 300. The lower right side of the housing 300 is provided with an exhaust chamber 302 corresponding to an exhaust end 312. When the compression mechanism works, air enters the compression cavities 310 of the pair of rotors from the air inlet channel 301, then is compressed into compressed air in the compression cavities 310, and finally the compressed air is discharged from the air outlet end 312 and enters the air outlet cavity 302.

As shown in fig. 5, the pair of rotors includes a male rotor 320 and a female rotor 330, a male rotor mounting groove 303 and a female rotor mounting groove 304 are provided in the housing 300 with axes extending in a transverse direction, the male rotor mounting groove 303 and the female rotor mounting groove 304 are communicated with each other, and the male rotor 320 and the female rotor 330 are rotatably disposed in the male rotor mounting groove 303 and the female rotor mounting groove 304, respectively. A slide valve mounting groove 305 communicated with the male rotor mounting groove 303 and the female rotor mounting groove 304 is also arranged below the male rotor mounting groove 303 and the female rotor mounting groove 304, and the male rotor mounting groove 303, the female rotor mounting groove 304 and the slide valve mounting groove 305 form an inverted triangle.

As shown in fig. 3 and 5, the slide valve 400 is slidably disposed in the slide valve mounting groove 305, and the slide valve 400 is disposed immediately below the male rotor 320 and the female rotor 330, and specifically, an upper end surface of the slide valve 400 is adjacent to the bottom of the male rotor 320 and the female rotor 330.

As shown in FIG. 3, the right end (also referred to as the first end) of spool valve 400 is provided with a spool valve exhaust port 410 (see FIG. 7), spool valve exhaust port 410 being located near exhaust end 312, spool valve exhaust port 410 communicating exhaust end 312 with exhaust chamber 302. A left end (also referred to as a second end) of the spool 400 is provided with a pressure adjustment chamber 500, and the pressure adjustment chamber 500 is a closed chamber formed by the inner wall of the housing 300 and the left end surface of the spool 400. The pressure adjusting chamber 500 is provided with a driving device 600, and the driving device 600 drives the slide valve 400 to move along the axial direction of the male rotor 320 and the female rotor 330 by changing the pressure of the pressure adjusting chamber 500 so as to change the effective opening size of the exhaust end 312 and adjust the internal volume ratio.

The effective opening size means: the size of the opening of the discharge end 312 with no spool valve 400 blocked minus the size of the opening of the discharge end 312 with the spool valve 400 blocked. By adjusting the effective opening size of the discharge end 312, the pressure at the discharge end can be adjusted, thereby adjusting the internal volume ratio.

As shown in fig. 7, the side of the slide valve 400 facing the male and

female rotors

320 and 330 is a working surface 420, the profile of the working surface 420 conforming to the profile of the male and

female rotors

320 and 330, and the working surface 420 being disposed immediately adjacent to the outer periphery of the male and

female rotors

320 and 330. Specifically, the middle of the working surface 420 is provided with a boundary 421 which protrudes upward and extends linearly, two sides of the boundary 421 are arc surfaces 422, and the radian of the arc surface 422 matches with the circumference of the corresponding male rotor 320 or female rotor 330.

As shown in fig. 7, the spool valve exhaust port 410 is located at an end portion of the working surface 420, and the opening size of the spool valve exhaust port 410 is gradually increased from the inside to the outside in the axial direction of the spool valve 400. Specifically, the inner end of spool valve exhaust port 410 is connected to dividing line 421, the outer end of spool valve exhaust port 410 extends outward and eventually to the end of spool valve 400, and further, it is noted that as spool valve exhaust port 410 gradually extends outward, the outer end of spool valve exhaust port 410 gradually expands radially outward, such that spool valve exhaust port 410 is V-shaped in cross section, with the opening of the V-shape facing the outer end of spool valve 400. From the above structure, the closer the slide valve outlet 410 is to the outlet end 312, the smaller the effective opening size; conversely, the larger the effective opening size.

As shown in fig. 6 and 7, a first blocking portion 430 is disposed at a first end of the sliding valve 400, a second blocking portion 340 is disposed on the housing 300, the second blocking portion 340 is located at a right end of the sliding valve 400, the second blocking portion 340 limits the first blocking portion 430, when the first blocking portion 430 of the sliding valve 400 abuts against the second blocking portion 340 of the housing 300, the effective opening size reaches a minimum value, and at this time, the internal volume ratio is maximum. In the present embodiment, the first blocking portion 430 is a flat surface disposed at an end of the spool valve 400. The second blocking portion 340 is a bearing seat provided at one end of the housing 300 for supporting ends of the male rotor 320 and the female rotor 330.

As shown in fig. 4, 6 and 7, a third blocking portion 440 protruding radially outward is provided on the second end of the sliding valve 400, a fourth blocking portion 350 extending toward the position where the sliding valve 400 is located is provided in the housing 300, the fourth blocking portion 440 is located at the left end of the male rotor 320 and the female rotor 330, the fourth blocking portion 350 at least partially overlaps with the third blocking portion 440 in the axial direction, and the fourth blocking portion 350 blocks the third blocking portion 440 at the outer end of the male rotor 320 and the female rotor 330, that is, the working surface 420 of the sliding valve 400 always seals the lower portion of the left side of the male rotor 320 and the lower portion of the left side of the female rotor 330 no matter where the sliding valve 400 is moved. In the present embodiment, the third blocking portion 440 is a plate-shaped structure provided at an end portion of the spool valve 400, and the fourth blocking portion 350 is a connection plate detachably provided inside the housing 300. In assembly, the spool valve 400 is first installed in the spool valve installation groove 305, and the connection plate is installed in the housing 300, thereby disposing the third stopper 440 at the outer end of the fourth stopper 350.

As shown in fig. 3, 4 and 10, the driving apparatus 600 includes a hydraulic passage 610, hydraulic oil (not shown) disposed in the hydraulic passage 610, and a control valve 630 controlling flow of the hydraulic oil, the hydraulic passage 610 includes an oil outlet hole 611 and an oil return hole 612, the oil outlet hole 611 and the oil return hole 612 are both located in the pressure-adjusting chamber 500, and the control valve 630 (typically, a solenoid valve) controls flow of the hydraulic oil in the oil outlet hole 611 and the oil return hole 612, adjusting the pressure of the pressure-adjusting chamber 500. The oil outlet hole 611 is relatively close to the outer end (left end in fig. 4) of the pressure adjustment chamber 500, and the oil return hole 612 is relatively close to the inner end (right end in fig. 4) of the pressure adjustment chamber 500. The oil return holes 612 may be provided in plural and distributed on the lower surface of the pressure adjustment chamber 500 in the axial direction to facilitate the return of the hydraulic oil at various positions.

When the driving device 600 is used, the control valve 630 controls hydraulic oil to enter the oil outlet hole 611, so that the pressure in the pressure adjusting chamber 500 is higher than that in the exhaust chamber 302, the slide valve 400 moves to the left for a certain distance, the pressures at the left and right ends of the slide valve 400 are balanced, and at the moment, the effective opening size of the exhaust end 312 is reduced due to the fact that the slide valve 400 moves to the right, and the internal volume ratio is increased. When it is necessary to reduce the internal volume ratio, the control valve 630 controls the hydraulic oil to enter the oil return hole 612, so that the pressure in the pressure adjusting chamber 500 is reduced, the spool 400 moves leftward, the pressures at the left and right ends of the spool 400 are balanced, and the effective opening size of the exhaust port 312, that is, the internal volume ratio, is reduced due to the leftward movement of the spool 400.

As shown in fig. 3, it is worth noting that the low-voltage stage motor 110 and the high-voltage stage motor 210 are respectively arranged in the low-voltage stage compression structure 100 and the high-voltage stage compression structure 200, and the low-voltage stage motor 110 and the high-voltage stage motor 210 respectively drive the corresponding male rotor and the corresponding female rotor to rotate, so that the gas amount of the first stage and the second stage can be steplessly adjusted, the requirements of different working conditions and different gas amounts are met, the adjustment of the external pressure ratio is realized, the external pressure ratio in a required state is achieved, and the purpose of saving energy is finally achieved.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention, including by way of illustration of the disclosed embodiments. Various modifications to these embodiments will be readily apparent to those skilled in the art. The general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A screw compressor with an adjustable internal volume ratio, comprising a compression mechanism, the compression mechanism comprising: the air compressor comprises a shell (300), a male rotor (320) and a female rotor (330) which are arranged in the shell (300) and meshed with each other, wherein a compression cavity (310) for compressing air is formed between the male rotor (320) and the female rotor (330) in a matching mode, the compression cavity (310) is provided with an air suction end (311) for air to enter and an air exhaust end (312) for air to exhaust, and the air compressor is characterized in that a slide valve (400) is further arranged in the shell (300), the slide valve (400) is arranged on one side of the male rotor (320) and the female rotor (330) in a close-proximity mode, the slide valve (400) is located on the side close to the air exhaust end (312), a slide valve air outlet (410) is arranged on the first end of the slide valve (400), the slide valve air outlet (410) is close to the air exhaust end (312), and the slide valve air outlet (410) is communicated with the air exhaust end (312) and an air exhaust cavity (302) of the shell (300); the second end of the slide valve (400) is provided with a pressure adjusting cavity (500), the pressure adjusting cavity (500) is internally provided with a driving device (600), and the driving device (600) drives the slide valve (400) to move along the axial directions of the male rotor (320) and the female rotor (330) by changing the pressure of the pressure adjusting cavity (500) so as to change the effective opening size of the exhaust end (312) and adjust the internal volume ratio.

2. -screw compressor according to claim 1, characterised in that the side of the slide valve (400) facing the male (320) and female (330) rotors is a working surface (420), the profile of the working surface (420) being adapted to the profile of the male (320) and female (330) rotors, and that the working surface (420) is arranged immediately on the outer circumference of the male (320) and female (330) rotors; the slide valve exhaust port (410) is positioned at the end part of the working surface (420), and the opening size of the slide valve exhaust port (410) is gradually increased from inside to outside in the axial direction of the slide valve (400).

3. The screw compressor of claim 2, wherein the inner end of the slide valve discharge port (410) is connected to the outer end of the working face (420), the outer end of the slide valve discharge port (410) extends axially outward to the end of the slide valve (400), and the outer end of the slide valve discharge port (410) gradually flares radially outward.

4. -screw compressor according to claim 3, characterised in that the slide valve discharge opening (410) is V-shaped in cross-section, the opening of the V-shape facing towards the outer end.

5. Screw compressor according to any one of claims 1-4, characterised in that the first end of the slide valve (400) is provided with a first stop (430), that the housing (300) is provided with a second stop (340), that the second stop (340) is located at one end of the slide valve (400), and that the second stop (340) limits the first stop (430).

6. Screw compressor according to any one of claims 1-4, characterised in that the second end of the slide valve (400) is provided with a third stop (440) extending radially outwards, that a fourth stop (350) is provided in the housing (300), that the fourth stop (350) is located at one end of the male rotor (320) and the female rotor (330), that the fourth stop (350) at least partly overlaps the third stop (440) in the axial direction, and that the fourth stop (350) stops the third stop (440) at the outer end of the male rotor (320) and the female rotor (330).

7. The screw compressor according to any one of claims 1 to 4, wherein the driving means (600) includes a hydraulic passage (610), hydraulic oil disposed in the hydraulic passage (610), and a control valve (630) controlling flow of the hydraulic oil, the hydraulic passage (610) includes an oil outlet hole (611) and an oil return hole (612), the oil outlet hole (611) and the oil return hole (612) are both located in the pressure-adjusting chamber (500), the oil return hole (612) is located on a lower surface of the pressure-adjusting chamber (500), and the control valve (630) controls flow of the hydraulic oil in the oil outlet hole (611) and the oil return hole (612) to adjust the pressure of the pressure-adjusting chamber (500).

8. -screw compressor according to claim 7, characterised in that the oil outlet (611) is relatively close to the outer end of the pressure regulation chamber (500) and the oil return (612) is relatively close to the inner end of the pressure regulation chamber (500); the oil return holes (612) are provided in plurality and distributed along the axial direction of the pressure adjustment chamber (500).

9. The screw compressor of claim 1, wherein the compression mechanism comprises a low-pressure stage compression mechanism (100) and a high-pressure stage compression mechanism (200) which are communicated with each other, and compressed air output by the low-pressure stage compression mechanism (100) is used as an air source on the suction side of the high-pressure stage compression mechanism (200); the low-pressure stage compression mechanism and the high-pressure stage compression mechanism (200) are respectively provided with a low-pressure stage motor (110) and a high-pressure stage motor (210), and the low-pressure stage motor (110) and the high-pressure stage motor (210) respectively drive a corresponding male rotor (320) and a corresponding female rotor (330) to rotate.