CN115585064A - A Shafting Structure of Air Bearing Miniature Centripetal Gas Turbine Generator - Google Patents

Abstract

An air bearing miniature centripetal gas turbine generator shafting structure, the generator rotor includes magnetic steel and a sheath, the magnetic steel and the sheath are assembled as a whole through interference fit, and the left radial journal and the sheath pass through The steps are positioned and installed on the left end of the center tie rod in turn, locked with a lock nut, the sheath and the center tie rod are positioned through the cylindrical surface, and the compressor impeller, combined thrust disc, right thrust disc and centripetal turbine are successively set on the center tie rod The right end is locked with a lock nut, the combined thrust disc is backed against the back of the compressor impeller, the right thrust disc is backed against the centripetal turbine, and the combined thrust disc acts as a left thrust disc and a radial journal at the same time. The present invention avoids the axial space required for installing the left and right thrust bearings by a separate thrust disc, shortens the axial length of the shaft system, and improves its bending rigidity. Easy installation and positioning after disassembly, no keyway and other structures prone to stress concentration, easy replacement of wearing parts, convenient heat dissipation and cooling of the generator rotor, and easy ultra-high-speed operation.

Description

A Shafting Structure of Air Bearing Miniature Centripetal Gas Turbine Generator

technical field

The invention belongs to the technical field of ultra-high-speed gas turbine generators, and relates to an air bearing type miniature centripetal gas turbine generator shafting structure.

Background technique

At present, micro gas turbine generator technology has been widely used in weapons and equipment such as tanks, radars, artillery vehicles, and missile systems. For micro gas turbine generator technology, the most critical core component is the gas turbine generator shafting. At present The widely used micro gas turbine generator shafting structure scheme generally adopts the method that the generator rotor is simply supported between two bearings, and the gas turbine and centrifugal compressor impellers are cantilevered outside the bearings on both sides. This kind of technical solution generally has the advantage of compact shaft structure, but the disadvantage is also very obvious, that is, during the working process of the gas turbine generator, the generator rotor is just placed inside the combustion chamber, so during the working process of the micro gas turbine generator, power generation It is difficult to solve the heat dissipation problem of the machine shaft system. At the same time, if this type of shaft system is supported by air bearings, a thrust plate needs to be specially installed in the general shaft system structure to solve the axial limit of the shaft system.

Contents of the invention

The technical problem solved by the invention is: to overcome the deficiencies of the prior art, and propose an air bearing type miniature centripetal gas turbine generator shafting structure.

The technical solution of the present invention is:

An air bearing miniature centripetal gas turbine generator shafting structure, including left radial journal, magnetic steel, sheath, compressor impeller, combined thrust disc, central pull rod, right thrust disc, centripetal turbine , the first lock nut and the second lock nut;

The middle part of the central tie rod is processed with a limited step, and the sheath is placed on the outside of the magnetic steel. The magnetic steel and the sheath are assembled into an integral structure through interference fit. On the limiting step, the magnetic steel and the left side of the sheath form a first step, the left radial journal is sleeved on the center rod, and the right side of the left radial journal is provided with a second step, the second step and The first step is limited and matched; the second lock nut is threaded with the left end of the center tie rod, and after tightening, the left radial journal is locked;

The central tie rod on the right side of the limit step is sequentially covered with compressor impeller, combined thrust disc, right thrust disc, and centripetal turbine; the thrust disc surface of the combined thrust disc is close to the back of the compressor impeller, and the right thrust disc is close to the centripetal On the back side of the type turbine, the first lock nut is threadedly matched with the right end of the center tie rod, and the small end face of the centripetal type turbine is locked after being tightened.

Preferably, both the compressor impeller and the centripetal turbine are in interference fit with the central tie rod.

Preferably, the small end surface of the impeller of the compressor abuts against the limiting step of the central tie rod.

Preferably, in the combined thrust disk, the cylindrical section on the right side of the thrust disk surface is the right radial journal.

Preferably, the right side of the thrust plate surface of the combined thrust plate and the left side of the right thrust plate are used for placing thrust bearings.

Preferably, the combustion chamber is connected between the combined thrust disk and the right thrust disk.

Preferably, the combined thrust plate and the compressor impeller are matched through steps.

Preferably, the combination thrust plate and the right thrust plate are matched through steps.

The beneficial effect of the present invention compared with prior art is:

The present invention avoids the axial space required for installing the left and right thrust bearings by a separate thrust disc, shortens the axial length of the shaft system, and improves its bending rigidity. Since the shafting structure adopts the combination of central tie rods, the torque transmission is transmitted through the friction force after compression, so it is easy to install and locate after disassembly, there is no keyway and other structures that are prone to stress concentration, easy to replace wearing parts, and the heat dissipation and cooling of the generator rotor are easy to achieve. Super fast operation.

Description of drawings

Fig. 1 is a three-dimensional structure view of the present invention;

Fig. 2 is a cross-sectional view of the present invention.

detailed description

The present invention will be further elaborated below in conjunction with embodiment.

The invention aims to solve the gas turbine generator shafting structure suitable for long-term high-reliability operation of air bearings. Fig. 1 is a three-dimensional structural view of the present invention, and Fig. 2 is a cross-sectional view of the present invention.

In the present invention, the magnetic steel 7 is interference-fitted in the sheath 8, the left radial journal 9 and the sheath 8 are positioned through the cylindrical surface, and the left radial journal 9 and the magnetic steel 7 are sequentially set on the left end of the center rod 1 , the sheath 8 is set on the limit step of the center rod shaft, and finally locked axially by the nut 10 on the left. The compressor impeller 2, the combined thrust disc 3, the right thrust disc 4 and the centripetal turbine 5 are successively set on the right end of the center tie rod 1, the thrust disc surface of the combined thrust disc 3 leans against the back of the compressor impeller 2, and the right thrust disc 4 rests on the On the back of the centripetal turbine 5, the small end surface of the compressor impeller 2 abuts against the limit step of the tie rod shaft, and finally the right nut 6 abuts against the small end surface of the centripetal turbine 5 for axial locking. In the combined thrust disk 3, the cylindrical section on the right side of the thrust disk surface is the right radial journal. The right side of the thrust disk surface of the combined thrust disk 3 and the left side of the right thrust disk 4 are used for placing thrust bearings. Combustion chamber is connected between combined thrust disk 3 and right thrust disk 4. The combined thrust disc 3 and the compressor impeller 2 are matched through steps. Combined thrust plate 3 and right thrust plate 4 cooperate by step.

Its working principle is: during the high-speed rotation of the shaft system, the compressor impeller 2 sucks and pressurizes the air in the environment, and the airflow sucked into the compressor can pass through the outer surface of the motor rotor magnet 7 and the sheath 8 Forced heat dissipation and cooling, the pressurized air burns through the combustion chamber and flows to the inlet of the centripetal turbine 5, driving the turbine to rotate at high speed, and the turbine coaxially drives the magnetic steel 7 and the sheath 8 to rotate synchronously, converting mechanical energy into electrical energy output. During the working process of the shaft system, the left radial journal 9 and the right radial journal on the combined thrust disc 3 cooperate with the radial air bearing in the complete machine to radially support the shaft system. By combining the thrust plate in the thrust plate 3 and the right thrust plate 4, the shafting can be axially limited.

In the present invention, the left radial journal, generator rotor, compressor impeller, combined thrust plate, right thrust plate, and centripetal turbine are sequentially assembled in series through a central pull rod, and both ends of the pull rod are axially locked by lock nuts. The generator rotor includes magnetic steel and sheath. The magnetic steel and the sheath are assembled as a whole through interference fit. The radial journal and the sheath are positioned through the cylindrical surface, and are sequentially placed on the left end of the center tie rod, and locked with a lock nut. , the sheath and the center tie rod are positioned through the cylindrical surface, the compressor impeller, the combined thrust disc, the right thrust disc and the centripetal turbine are set on the right end of the center tie rod in turn, locked with a lock nut, and the combined thrust disc is backed against the back of the compressor impeller 1. The right thrust plate is backed by the centripetal turbine, and the combined thrust plate plays the role of the left thrust plate and the right radial journal at the same time.

During the working process, the radial journal on the left side cooperates with the radial bearing on the right side of the combined thrust disc, which provides radial support for the shafting structure. The left thrust disc in the combined thrust disc mainly cooperates with the thrust bearing. It is used to limit the leftward movement of the shafting system, and the right thrust plate is used to limit the rightward movement of the shafting system.

This kind of shaft arrangement structure avoids the axial space required for the left and right thrust bearings installed by a separate thrust plate, shortens the axial length of the shaft, and improves its bending stiffness. Since the shafting structure adopts the combination of central tie rods, the torque transmission is transmitted through the friction force after compression, so it is easy to install and locate after disassembly, there is no keyway and other structures that are prone to stress concentration, easy to replace wearing parts, and the heat dissipation and cooling of the generator rotor are easy to achieve. Super fast operation.

The outer diameter of the radial journal on the left side of the present invention does not exceed 30mm, the overall radial dimension does not exceed 70mm, and the axial length does not exceed 200mm. The shaft system can work stably at a speed of more than 100,000rpm, and the maximum output power of the generator can reach 30kW.

The present invention has carried out the creative design on the centrifugal compressor impeller, generator rotor, centripetal turbine and radial air bearing journal and thrust bearing thrust disc structural arrangement; the shafting structure is generator rotor-compressor impeller- Centripetal turbine assembly structure, two radial air bearing journals are respectively placed outside the generator rotor and between the compressor impeller and the centripetal turbine, and the thrust discs of the two thrust bearings are respectively attached to the compressor impeller and the centripetal turbine back. The invention has the advantage that during the working process of the shafting of the gas turbine generator, the generator rotor is far away from the combustion chamber and other heat-generating components, so that the heat dissipation design is easy to realize, and at the same time, the suction air flow of the compressor impeller can be introduced to the outside of the generator rotor to further dissipate heat. Since the shafting structural parts all adopt the tandem assembly structure, the processing and assembly are simple, and the journal of the radial air bearing and the thrust disc of the thrust bearing can be replaced according to the wear condition. The invention solves the problem of cooling and heat radiation in the working process of the shaft system of the micro gas turbine generator, simplifies the support mode of the shaft system, and improves the working reliability of the shaft system.

The content that is not described in detail in the specification of the present invention belongs to the well-known technology of those skilled in the art.

Claims (8)

1. The utility model provides an air bearing formula miniature centripetal gas turbine generator shafting structure which characterized in that: the centrifugal compressor comprises a left radial journal (9), magnetic steel (7), a sheath (8), a compressor impeller (2), a combined thrust disc (3), a central pull rod (1), a right thrust disc (4), a centripetal turbine (5), a first locking nut (6) and a second locking nut (10);

a limiting step is processed in the middle of the central pull rod (1), the sheath (8) is sleeved on the outer side of the magnetic steel (7), the magnetic steel (7) and the sheath (8) are assembled into an integral structure through interference fit, the integral structure is sleeved on the central pull rod (1) from the left side, the sheath (8) is sleeved on the limiting step of the central pull rod (1), the magnetic steel (7) and the left side of the sheath (8) form a first step, a left radial journal (9) is sleeved on the central pull rod (1), a second step is arranged on the right side of the left radial journal (9), and the second step is in limiting fit with the first step; the second locking nut (10) is in threaded fit with the left end of the central pull rod (1), and the left radial journal (9) is locked after being screwed down;

a central pull rod (1) on the right side of the limiting step is sequentially sleeved with a compressor impeller (2), a combined thrust disc (3), a right thrust disc (4) and a centripetal turbine (5); the thrust disc surface of the combined thrust disc (3) is tightly attached to the back surface of the compressor impeller (2), the right thrust disc (4) is tightly attached to the back surface of the centripetal turbine (5), the first locking nut (6) is in threaded fit with the right end of the central pull rod (1), and the small end surface of the centripetal turbine (5) is locked after being screwed down.

2. The air bearing micro centripetal gas turbine generator shafting structure according to claim 1, wherein: the compressor impeller (2) and the centripetal turbine (5) are in interference fit with the central pull rod (1).

3. The shafting structure of an air bearing miniature centripetal gas turbine generator according to claim 2, wherein: the small end surface of the compressor impeller (2) is propped against the central pull rod limiting step.

4. The shafting structure of an air bearing miniature centripetal gas turbine generator according to claim 1, wherein: in the combined thrust disc (3), the cylindrical section on the right side of the thrust disc surface is a right radial journal.

5. The shafting structure of an air bearing miniature centripetal gas turbine generator according to claim 1, wherein: the right side of the thrust disc surface of the combined thrust disc (3) and the left side of the right thrust disc (4) are used for placing a thrust bearing.

6. The shafting structure of an air bearing miniature centripetal gas turbine generator according to claim 5, wherein: a combustion chamber is connected between the combined thrust disc (3) and the right thrust disc (4).

7. The shafting structure of an air bearing miniature centripetal gas turbine generator according to claim 1, wherein: the combined thrust disc (3) is matched with the compressor impeller (2) through a step.

8. The air bearing micro centripetal gas turbine generator shafting structure according to claim 1, wherein: the combined thrust disc (3) is matched with the right thrust disc (4) through a step.

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