CN115355171A

CN115355171A - Combined sealed oilless screw blower

Info

Publication number: CN115355171A
Application number: CN202211082134.3A
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: 2022-09-06
Filing date: 2022-09-06
Publication date: 2022-11-18

Abstract

The invention relates to the field of air compressors, in particular to a combined type sealed oil-free screw blower, which comprises: a fuselage having a compression chamber and a lubrication chamber; the female rotor and the male rotor are rotatably arranged in the machine body, rotating shafts are arranged at two ends of the female rotor and the male rotor, the rotating shafts are connected with the machine body through bearings, and the bearings are positioned in the lubricating cavity; a sealing structure is arranged on the side, close to the compression cavity, of the bearing and is arranged on the outer peripheral surface of the rotating shaft, and the sealing structure prevents lubricating oil in the lubricating cavity from entering the compression cavity; the seal structure includes: the oil retainer ring, the spiral sealing seat and the carbon ring are sequentially arranged along the axial direction, the oil retainer ring is positioned on one side of the bearing, spiral sealing is formed between the spiral sealing seat and the rotating shaft, and floating sealing is formed between the carbon ring and the rotating shaft. The invention has the advantages that the sealing performance of the compression cavity is improved by combining a plurality of sealing modes, oil and gas can be effectively isolated, and the operation reliability of a machine is ensured.

Description

Combined sealed oil-free screw blower

Technical Field

The invention relates to the field of air compressors, in particular to a combined sealed oil-free screw blower.

Background

Oil-free screw rod air-blower is including setting up cloudy rotor and the positive rotor in the fuselage, and between cloudy rotor and the positive rotor direct contact not, both connect through the synchro gear who sets up in one end, and when one of them rotor was rotatory, this rotor drove another rotor counter-rotation through synchro gear, realized the compression of air. Unlike oil-injected screw blowers, oil injection is not required on the female rotor and the male rotor during operation of an oil-free screw blower, so that air does not contact with oil, and pure compressed air can be obtained. However, the bearings on the female and male rotors and the synchronizing gears still need to be cooled by a lubricating oil lubrication box and to prevent these lubricating oils from entering the compression chamber, so in an oil-free screw blower, sealing of both ends of the compression chamber is particularly important.

Disclosure of Invention

In order to solve the above problems, an object of the present invention is to provide a combined sealed oil-free screw blower, in which an oil baffle ring, a spiral seal seat and a carbon ring are sequentially disposed along an axial direction on a side of a bearing close to a compression cavity, a main lubricating oil is blocked by the oil baffle ring, and a small part of the rest of the lubricating oil is blocked outside the compression cavity under the action of the spiral seal seat and the carbon ring, so as to ensure the sealing performance of the compression cavity.

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

a combination sealed oil-free screw blower comprising:

a fuselage having a compression chamber and a lubrication chamber;

the female rotor and the male rotor are rotatably arranged in the machine body, rotating shafts are arranged at two ends of the female rotor and the male rotor, the rotating shafts are connected with the machine body through bearings, and the bearings are positioned in the lubricating cavity;

a sealing structure is arranged on the side, close to the compression cavity, of the bearing and is arranged on the outer peripheral surface of the rotating shaft, and the sealing structure prevents lubricating oil in the lubricating cavity from entering the compression cavity;

the seal structure includes: the oil scraper ring, the spiral seal seat and the carbon ring are sequentially arranged along the axial direction, the oil scraper ring is positioned on one side of the bearing, spiral seal is formed between the spiral seal seat and the rotating shaft, and floating seal is formed between the carbon ring and the rotating shaft.

Preferably, the radially outer end of the slinger extends to the bearing outer race; an oil return channel is arranged on the machine body at a position corresponding to the oil retainer ring and is communicated with the lubricating cavity; and the lubricating oil blocked by the oil deflector ring flows back to the lubricating cavity through the oil return channel.

Preferably, the inner surface of the spiral sealing seat is provided with a thread, the position on the rotating shaft connected with the spiral sealing seat is a smooth surface, and the rotation direction of the thread is the same as the rotation direction of the rotating shaft, so that spiral sealing is formed between the spiral sealing seat and the rotating shaft.

Preferably, the side of the spiral seal holder facing the bearing is provided with an axially extending locating end, the locating end abuts against one side of the bearing, and the oil slinger is positioned at the inner side of the locating end.

Preferably, the positioning end is a plurality of protrusions which are arranged on the side surface of the spiral sealing seat and distributed around the circumferential direction, and gaps are formed among the protrusions.

Preferably, a carbon ring positioning assembly is disposed between the spiral seal housing and the carbon ring, the carbon ring positioning assembly preventing the carbon ring from moving axially.

Preferably, the carbon ring positioning assembly comprises a carbon ring positioning seat arranged on one side of the spiral sealing seat and an elastic element arranged between the carbon ring positioning seat and the carbon ring, the carbon ring positioning seat is positioned through the machine body, the elastic element exerts force on the carbon ring, and the carbon ring is positioned on the rotating shaft.

Preferably, the machine body is provided with a first positioning groove and a second positioning groove, the carbon ring is arranged in the first positioning groove, and the carbon ring positioning seat is arranged in the second positioning groove; a through hole communicated with the outside is arranged between the first positioning groove and the second positioning groove, and the inner end of the through hole is positioned in the sealing structure.

In conclusion, the invention has the advantages that: most of lubricating oil in the bearing is blocked by the oil deflector ring and flows back to the lubricating cavity, and a small part of lubricating oil passes over the oil deflector ring and is blocked by the spiral sealing seat, and when the spiral sealing seat fails in sealing, the leaked lubricating oil is blocked by the carbon ring. Through the combination of a plurality of sealed modes, improved the sealing performance of compression chamber, can effectively isolated oil and gas, guarantee the operational reliability of machine.

Drawings

Fig. 1 is a perspective view of an oil-free screw blower.

Fig. 2 is a left side view of the oil-free screw blower.

Fig. 3 is a cross-sectional view at B-B in fig. 2.

Fig. 4 is a partially enlarged view of a portion a in fig. 3.

Fig. 5 is an exploded view of the composite seal.

Detailed Description

As shown in fig. 1 and 3, an oil-free screw blower includes a body 10, a compression chamber 101 is provided inside the body 10, a female rotor 20 and a male rotor 30 are provided in the compression chamber 101 side by side, the axes of the female rotor 20 and the male rotor 30 extend in a transverse direction, both left and right ends of the female rotor 20 and the male rotor 30 are rotating

shafts

21, 31, and both the

rotating shafts

21, 31 at both ends are rotatably provided in the body 10 through

bearings

22, 32. The middle parts of the female rotor 20 and the male rotor 30 are in an asymmetric spiral tooth structure, and the female rotor and the male rotor are meshed with each other through spiral teeth so as to realize the compression of air. An intake port 11 communicating with the compression chamber 101 is provided at the top of the body 10, and an exhaust port 12 communicating with the compression chamber 101 is provided at the bottom of the body 10. When the apparatus is operated, the female rotor 20 and the male rotor 30 rotate simultaneously and rotate in opposite directions, and outside air is sucked into the compression chamber 101 from the air inlet 11 at the top of the body 10, and in the compression chamber 101, the air is compressed by the female rotor 20 and the male rotor 30, and the compressed air flows downward and is discharged from the air outlet 12 at the bottom of the body 10.

As shown in fig. 3, the left end of the body 10 is a driving end for connecting a driving device (not shown), and an output end of the driving device is connected to the female rotor 20 or the male rotor 30 for driving the rotors to rotate. Generally, the driving device may employ a motor. In the present embodiment, a driving device is connected to the female rotor 20, i.e., the driving device is used for driving the female rotor 20 to rotate. As shown in fig. 2, a pair of synchronizing gears 40, 40 'engaged with each other are provided at right ends of the female rotor 20 and the male rotor 30 such that the female rotor 20 rotates the male rotor 30 in a reverse direction by the synchronizing gears 40, 40' when the female rotor 20 is rotated by the driving means.

In order to lubricate the

bearings

22 and 32 and the synchronous gears 40 and 40', lubricating cavities 102 are arranged at the left end and the right end of the machine body 10, the lubricating cavities 102 and the compression cavities 101 are sealed through sealing structures, lubricating oil in the lubricating cavities is prevented from flowing into the compression cavities 101, and normal operation of the equipment is guaranteed.

In the present embodiment, a sealing structure on the left side of the female rotor 20 is taken as an example, and a specific structure of the sealing structure will be described.

As shown in fig. 4 and 5, the rotating shaft 21 of the female rotor 20 is provided with a bearing 22, and the left side of the bearing 22 is connected to a lubrication chamber, and the bearing 22 can be lubricated and cooled by the lubricating oil in the lubrication chamber (usually, splash lubrication). The sealing structure is provided on the right side of the bearing 22, i.e., the side close to the compression chamber 101. The seal structure is provided on the outer peripheral surface of the rotating shaft 21, and includes: the oil slinger comprises an oil slinger 50, a spiral sealing seat 60 and a carbon ring 70 which are sequentially arranged along the axial direction, wherein the oil slinger 50, the spiral sealing seat 60 and the carbon ring 70 are all of annular structures, and the rotating shaft 21 is arranged inside the oil slinger 50, the spiral sealing seat 60 and the carbon ring 70.

The slinger 50 is configured such that the slinger 50 is fitted around the outer peripheral surface of the rotating shaft 21, the left side of the slinger 50 is in close contact with the right side of the bearing 22, and the inner ring of the slinger 50 is in close contact with the inner ring of the bearing 22 to position the bearing 22. The right side of the slinger 50 is positioned by the step 211 on the rotating shaft 21. In a radial direction, the outer end of the slinger 50 extends to the outer ring of the bearing 22, and the lubricating oil in the bearing 22 is once discharged from the bearing 22 and is blocked by the slinger 50. An oil return passage 13 is also provided in the body 10, and the oil return passage 13 is located radially outside the oil slinger 50, so that the lubricating oil stopped by the oil slinger 50 can enter the oil return passage 13 and flow back into the lubricating chamber along the oil return passage 13.

In the screw seal holder 60, the screw thread 61 is provided on the inner surface of the screw seal holder 60, the screw thread 61 abuts on the outer peripheral surface of the rotating shaft 21, and the screw thread 61 is rotated in the same direction as the rotating direction of the rotating shaft 21, thereby ensuring the sealing performance inside the screw seal holder 60. The outer peripheral surface of the rotating shaft 21 is a smooth surface, and the screw seal holder 60 is not fixedly connected to the rotating shaft 21 by the screw 61, but forms a screw seal by the screw 61. The specific sealing principle will be described in detail later. The outer surface of the spiral seal seat 60 is provided with a first groove 62 which extends around the circumferential direction to form a ring shape, a first seal ring 621 is arranged in the first groove 62, and the first seal ring 621 abuts against the inner wall of the machine body 10, so that the sealing performance of the outer side of the spiral seal seat 60 is ensured. A positioning end 63 extending in the direction of the bearing 22 is provided on the left side of the screw seal holder 60, and the left side of the positioning end 63 abuts against the right side of the outer ring of the bearing 22 to position the bearing 22 in the axial direction. And the positioning end 63 is located radially outward of the slinger 50. Preferably, the positioning end 63 is a plurality of protrusions spaced along the circumferential direction, so that a gap is formed between adjacent protrusions, and the lubricating oil in the slinger 50 flows into the oil return passage 13 through the gap.

In the case of the carbon ring 70, the carbon ring 70 is disposed in the first positioning groove 14 of the body 10, the inner side of the carbon ring 70 is closely attached to the rotating shaft 21, and the carbon ring 70 is a floating sealing mechanism that effectively prevents leakage by using the tension of an oil film. Be provided with the carbocycle locating component 80 that is used for advancing line location to carbocycle 70 between the left side of carbocycle 70 and the right side of spiral seal seat 60, it is specific, carbocycle locating component 80 includes carbocycle positioning seat 81 and elastic element 82, and carbocycle positioning seat 81 sets up in the second constant head tank 15 of fuselage 10 to the left side of carbocycle positioning seat 81 and the right side butt of spiral seal seat 60 are used for advancing line location to spiral seal seat 60. An elastic member 82 (e.g., a spring, preferably a wave spring) is disposed at the right side of the carbon ring positioning seat 81, and the elastic member 82 applies a force to the carbon ring 70 to fix the carbon ring 70 in the first positioning groove 14 and prevent the carbon ring from moving in the axial direction. A second groove 811 extending circumferentially to form a ring is further formed in the wall surface on the right side of the carbon ring positioning seat 81, a second seal ring 8111 is arranged in the second groove 811, and the second seal ring 8111 abuts against the inner wall of the machine body 10.

A through hole 16 communicating with the outside air is provided between the first and

second positioning grooves

14 and 15 of the body 10, an axis of the through hole 16 extends in a horizontal direction, and an inner end of the through hole 16 is located at a radial outer side of the carbon ring 70.

The sealing principle of the sealing structure is explained in detail as follows:

when the device is in operation, the lubricating oil in the lubricating cavity 102 enters the bearing 22 by way of splash lubrication, so as to lubricate and cool the bearing 22, and part of the lubricating oil flows to the right side of the bearing 22 along the axial direction, at this time, the oil deflector ring 50 blocks the lubricating oil and prevents the lubricating oil from continuously moving along the axial direction, so that most of the lubricating oil flows along the radial direction, flows into the oil return channel 13 and finally flows back to the lubricating cavity. However, a small amount of lubricant will pass the slinger 50 and enter the screw seal holder 60, i.e. the lubricant flows into the thread 61 of the screw seal holder 60, and since the rotation direction of the thread 61 is the same as the rotation direction of the rotating shaft 21, the screw seal holder 60 forms a propulsion device, which exchanges energy with the medium to generate a so-called "pumping action" to suck air in the atmosphere into the thread 61 and convey the air to the lubricating cavity, i.e. a pumping head is generated, which is balanced with the pressure of the sealed medium (lubricant), thereby preventing the lubricant from leaking. If the screw seal 60 fails, the oil will continue to flow to the right over the threads 61, where it will be blocked by the carbon ring 70, the carbon ring 70 being a floating seal that seals against the oil using the tension of the oil film.

In summary, the present invention has the advantages that most of the lubricating oil in the bearing is blocked by the oil deflector ring and flows back to the lubricating cavity, and a small part of the lubricating oil passes over the oil deflector ring and is blocked by the spiral seal seat, and when the spiral seal seat fails in sealing, the carbon ring blocks the leaked lubricating oil. Through the combination of a plurality of sealed modes, improved the sealing performance of compression chamber, can effectively isolated oil and gas, guarantee the operational reliability of machine.

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 any reference to the above-mentioned 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 combination sealed oil-free screw blower comprising:

a fuselage having a compression chamber and a lubrication chamber;

it is characterized in that the preparation method is characterized in that,

2. An oil-free screw blower of the type having a combined seal according to claim 1, wherein the radially outer end of the slinger extends to the bearing outer race; an oil return channel is arranged on the machine body at a position corresponding to the oil retainer ring and is communicated with the lubricating cavity; and the lubricating oil blocked by the oil deflector ring flows back to the lubricating cavity through the oil return channel.

3. An oil-free screw blower with combined seal as claimed in claim 1, wherein the screw seal seat is provided with a screw thread on its inner surface, the position of the rotating shaft connected with the screw seal seat is a smooth surface, and the screw thread has the same direction as the rotating direction of the rotating shaft, so that the screw seal is formed between the screw seal seat and the rotating shaft.

4. A combined sealed oil-free screw blower according to any one of claims 1 to 3, wherein the side of the spiral seal holder facing the bearing is provided with an axially extending locating end which abuts against the side of the bearing, and the oil slinger is located inwardly of the locating end.

5. An oil-free screw blower with a combined seal according to claim 4, wherein the positioning end is a plurality of protrusions arranged on the side of the spiral seal seat and distributed around the circumference, and gaps are formed among the protrusions.

6. An oil-free screw blower with a combined seal according to claim 1, wherein a carbon ring positioning assembly is provided between the screw seal seat and the carbon ring, the carbon ring positioning assembly preventing the carbon ring from moving axially.

7. The combination sealed oil-free screw blower according to claim 6, wherein the carbon ring positioning assembly includes a carbon ring positioning seat disposed at one side of the spiral sealing seat and an elastic element disposed between the carbon ring positioning seat and the carbon ring, the carbon ring positioning seat is positioned by the body, and the elastic element exerts a force on the carbon ring to position the carbon ring on the rotating shaft.

8. An oil-free screw blower with a combined seal according to claim 7, wherein the body is provided with a first positioning groove and a second positioning groove, the carbon ring is arranged in the first positioning groove, and the carbon ring positioning seat is arranged in the second positioning groove; a through hole communicated with the outside is arranged between the first positioning groove and the second positioning groove, and the inner end of the through hole is positioned in the sealing structure.