CN216381859U

CN216381859U - Dry-type double-acting double-screw compressor

Info

Publication number: CN216381859U
Application number: CN202123277063.6U
Authority: CN
Inventors: 柯建汝
Original assignee: Zhejiang Chuangwei Vacuum Equipment Share Co ltd
Current assignee: Zhejiang Chuangwei Vacuum Equipment Share Co ltd
Priority date: 2021-12-23
Filing date: 2021-12-23
Publication date: 2022-04-26
Anticipated expiration: 2031-12-23

Abstract

The utility model provides a dry double-acting double-screw compressor, and belongs to the technical field of compressors. The double-screw compressor solves the problems that an existing double-screw compressor is large in axial force and short in service life. The dry double-acting double-screw compressor comprises a shell, wherein a pair of screws are arranged in the shell in a penetrating mode, a section of air release cavity is arranged in the middle of each screw, threads on the screws are divided into a left section and a right section by the air release cavity, the thread pitches of the left section and the right section of threads are gradually reduced from two ends of the shell to the middle, air inlet channels are arranged at two ends of the shell, an air outlet channel is arranged in the middle of the shell, and the air release cavities are communicated with the air outlet channels. The dry double-acting double-screw compressor has the advantages of reducing the axial force of the screw and prolonging the service life of the compressor.

Description

Dry-type double-acting double-screw compressor

Technical Field

The utility model belongs to the technical field of compressors, and relates to a dry-type double-acting double-screw compressor.

Background

The medium in the compression cavity of the oil-free screw compressor is not contacted with lubricating oil, and the compression cavity is dry, so the oil-free screw compressor is also called a dry screw compressor and is also called a dry screw vacuum pump.

For example, chinese patent literature discloses an anticorrosive dry screw vacuum pump [ application No.: 202023338323.1, respectively; authorization notice number: CN214063284U ], the anticorrosion dry screw vacuum pump comprises an inner casing, a rotor is arranged in the inner casing, a first annular supplement sleeve and a second annular supplement sleeve which are made of anticorrosion metal material are respectively arranged at two ends of the inner casing, and two ends of the rotor are respectively arranged in the first supplement sleeve and the second supplement sleeve in a penetrating way.

The rotor of this kind of structure wears to establish in whole interior casing, the air inlet is located the one end of interior casing, the gas vent is located the other end of interior casing, low temperature low pressure gas enters into interior casing from the air inlet, after the compression of rotatory rotor, become the highly compressed gas of high temperature, the gas vent of interior casing is discharged, this gas pressure at both ends is different about just making interior casing, can make the rotor receive great axial force, this bearing that just leads to the rotor both ends, the load that first benefit cover and second benefit cover bore is high, a bearing, first benefit cover and second benefit cover damage easily, make sealed inefficacy, can cause whole vacuum pump to damage even, the life of vacuum pump is low.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a dry double-acting double-screw compressor aiming at the problems in the prior art, and solves the technical problem of how to reduce the axial force of screws and prolong the service life of the compressor.

The purpose of the utility model can be realized by the following technical scheme: the dry double-acting double-screw compressor comprises a shell, wherein a pair of screws are arranged in the shell in a penetrating mode, and the dry double-acting double-screw compressor is characterized in that a section of air release cavity is arranged in the middle of each pair of screws, threads on the screws are divided into a left section and a right section by the air release cavity, the thread pitches of the left section and the right section of threads are gradually reduced from two ends of the shell to the middle of the shell, air inlet channels are arranged at two ends of the shell, an air outlet channel is arranged in the middle of the shell, and the air release cavities are communicated with the air outlet channels.

The low-temperature and low-pressure gas enters the shell from the gas inlet channels at the two ends of the shell, the screw rotates, the gas flows towards the middle of the screw and the middle of the shell along the screw, in the process, as the screw pitches of the left section of screw thread and the right section of screw thread are gradually reduced from the two ends of the shell towards the middle, the gas is gradually compressed to be high-pressure gas, and then the high-pressure gas enters the gas discharge cavity and is discharged through the gas outlet channel. The compressor has the advantages that the gas moves from the two ends of the shell to the middle, the gas entering from the two ends is symmetrical, the directions of the generated axial forces are opposite, the axial forces generated on the screw rods are mutually offset, and the screw rods are not subjected to the axial forces or are subjected to smaller axial forces, so that the loads of bearings, sealing structures and the like between the screw rods and the shell are low, the compressor is not easy to damage, and the service life of the compressor is prolonged.

In the above-mentioned dry-type double-acting twin-screw compressor, the two air inlet channels are respectively located at the top of the two ends of the shell, and the air outlet channel is located at the side of the bottom of the shell. The structure makes the compressor reasonable in structure and arrangement.

In the above-mentioned dry-type double-acting twin-screw compressor, the air outlet channel is in a flared shape, and the bottom wall of the air outlet channel is obliquely arranged downwards from inside to outside. By adopting the structure, high-pressure gas in the shell can be better discharged from the shell.

In the dry double-acting double-screw compressor, the caliber of the inner end of the air outlet channel is slightly smaller than the width of the air discharge cavity along the axial direction of the screw, and the inner end of the air outlet channel is positioned between the left section of screw thread and the right section of screw thread. With this configuration, the pressure of the compressed gas compressed by the rotation of the screw is maximized, and the compressed gas is pushed out of the housing in a state of the maximum pressure.

In the dry double-acting double-screw compressor, the top of the shell is fixedly connected with an air inlet pipe, the middle of the air inlet pipe is provided with an air inlet, and two ends of the air inlet pipe are communicated with an air inlet channel of the shell. The air inlet pipe is arranged in a bilateral symmetry mode, so that the axial force generated by the gas entering the shell to the screw rod is more balanced, the axial force applied to the screw rod is reduced, and the service life of the compressor is prolonged.

In the dry-type double-acting double-screw compressor, the edge of the air inlet pipe is upwards protruded to form a surrounding edge, and the top of the surrounding edge is outwards protruded to form a fixing ring. The structure enables the air inlet pipe to be connected with a pipe better.

In the above-mentioned dry-type double-acting twin-screw compressor, the air inlet pipe is in a bow shape, and a damping space is provided between the air inlet pipe and the shell. This kind of structure can reduce the vibrations of intake pipe to a certain extent, improves the stability of compressor.

In the above-described dry double-acting twin-screw compressor, the housing has therein a cooling chamber for storing a cooling medium, the cooling chamber being disposed along a circumferential direction of the housing. And a cooling medium is arranged in the cooling cavity, so that the effect of cooling the gas in the shell is achieved, and the running stability of the compressor is improved.

Compared with the prior art, the dry-type double-acting double-screw compressor provided by the utility model has the following advantages:

1. the compressor has the advantages that the gas moves from the two ends of the shell to the middle, the gas entering from the two ends is symmetrical, the directions of the generated axial forces are opposite, the axial forces generated on the screw rods are mutually offset, and the screw rods are not subjected to the axial forces or are subjected to smaller axial forces, so that the loads of bearings, sealing structures and the like between the screw rods and the shell are low, the compressor is not easy to damage, and the service life of the compressor is prolonged.

2. The structure of the air outlet channel of the compressor is more beneficial to discharging high-pressure gas in the shell, so that the compressor can run smoothly and stably.

Drawings

Fig. 1 is a sectional view of the compressor in the axial direction of the screw.

Fig. 2 is a sectional view of the compressor in the screw radial direction.

In the figure, 1, a housing; 11. an air intake passage; 12. an air outlet channel; 2. a screw; 21. an air discharge cavity; 22. screw teeth; 3. an air inlet pipe; 31. an air inlet; 32. surrounding edges; 33. a fixing ring; 4. a shock absorbing space; 5. and a cooling cavity.

Detailed Description

The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments.

As shown in fig. 1, the present dry type double-acting twin-screw compressor includes a casing 1, a pair of screws 2, and an intake pipe 3. The housing 1 has a cooling chamber 5 therein for storing a cooling medium, the cooling chamber 5 being arranged in the circumferential direction of the housing 1.

The middle of each pair of screw rods 2 is provided with a section of air release cavity 21, the screw teeth 22 on the screw rods 2 are divided into a left section and a right section by the air release cavities 21, and the screw pitches of the left section and the right section of screw teeth 22 are gradually reduced from the two ends of the shell 1 to the middle. The top of the two ends of the shell 1 is provided with an air inlet channel 11, the side of the middle bottom of the shell 1 is provided with an air outlet channel 12, the air outlet cavity 21 is communicated with the air outlet channel 12, as shown in fig. 2, the air outlet channel 12 is in a flaring shape, and the bottom wall of the air outlet channel 12 is obliquely arranged downwards from inside to outside. The caliber of the inner end of the air outlet channel 12 is slightly smaller than the width of the air discharge cavity 21 along the axial direction of the screw rod 2, and the inner end of the air outlet channel 12 is positioned between the left section of screw thread 22 and the right section of screw thread 22.

The top of casing 1 is linked firmly intake pipe 3, and intake pipe 3 is the bow-shaped, and the both ends of intake pipe 3 are linked together with the inlet channel 11 of casing 1, have shock attenuation space 4 between intake pipe 3 and the casing 1. The middle of the air inlet pipe 3 is provided with an air inlet 31, the edge of the air inlet 31 of the air inlet pipe 3 protrudes upwards to form a surrounding edge 32, and the top of the surrounding edge 32 protrudes outwards to form a fixing ring 33.

In operation, low-temperature and low-pressure gas enters from the gas inlet 31 of the gas inlet pipe 3 and flows along the gas inlet pipe 3, then enters into the two ends of the shell 1 through the gas inlet channel 11, and flows along with the screw 2 and is compressed to enter the gas discharge cavity 21 under the action of the rotating screw 2, and finally is discharged from the gas outlet channel 12.

The specific embodiments described herein are merely illustrative of the spirit of the utility model. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the utility model as defined in the appended claims.

Although the terms of the housing 1, the inlet channel 11, the outlet channel 12, the screw 2, the venting chamber 21, the thread 22, the inlet tube 3, the inlet opening 31, the skirt 32, the securing ring 33, the damping space 4, the cooling chamber 5, etc. are used more often herein, the possibility of using other terms is not excluded. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed as being without limitation to any additional limitations that may be imposed by the spirit of the present invention.

Claims

1. The dry double-acting double-screw compressor comprises a shell (1), wherein a pair of screws (2) are arranged in the shell (1) in a penetrating mode, and the dry double-acting double-screw compressor is characterized in that a venting cavity (21) is formed in the middle of each pair of screws (2), threads (22) on each screw (2) are divided into a left section and a right section by the venting cavity (21), the thread pitches of the left section and the right section of the threads (22) are gradually reduced from two ends of the shell (1) to the middle, air inlet channels (11) are formed in two ends of the shell (1), an air outlet channel (12) is formed in the middle of the shell (1), and the venting cavity (21) is communicated with the air outlet channel (12).

2. A dry double-acting double-screw compressor according to claim 1, characterized in that the two inlet channels (11) are located respectively at the top of the two ends of the shell (1), and the outlet channel (12) is located at the side of the bottom of the shell (1).

3. A dry double-acting double-screw compressor according to claim 1 or 2, characterized in that the outlet channel (12) is flared, and the bottom wall of the outlet channel (12) is inclined downwards from inside to outside.

4. A dry double-acting double-screw compressor according to claim 1 or 2, characterized in that the caliber of the inner end of the air outlet channel (12) is slightly smaller than the width of the air discharge chamber (21) along the axial direction of the screw (2), and the inner end of the air outlet channel (12) is positioned between the left and right sections of the screw teeth (22).

5. A dry double-acting double-screw compressor according to claim 1 or 2, characterized in that the top of the shell (1) is fixedly connected with an air inlet pipe (3), the air inlet pipe (3) is provided with an air inlet (31) in the middle, and the two ends of the air inlet pipe (3) are communicated with the air inlet channel (11) of the shell (1).

6. A dry double-acting twin-screw compressor according to claim 5, characterised in that the rim of the air inlet (31) of the air inlet pipe (3) is provided with an upwardly projecting peripheral edge (32), the top of the peripheral edge (32) being provided with an outwardly projecting retaining ring (33).

7. A dry double-acting twin-screw compressor according to claim 5, characterised in that the air inlet pipe (3) is arched, with a damping space (4) between the air inlet pipe (3) and the casing (1).

8. A dry double-acting twin-screw compressor according to claim 1 or 2, characterised in that the housing (1) has cooling chambers (5) therein for storing a cooling medium, the cooling chambers (5) being arranged in the circumferential direction of the housing (1).