CN116006584A - Long-life aviation bearing capable of completely and automatically compensating abrasion - Google Patents

Abstract

A novel long-life aviation bearing with abrasion capable of being fully and automatically compensated is compared with the existing high-end bearing and an aviation engine main bearing. The method is characterized in that: the outer ring of the bearing is formed by screwing and combining about half of the outer rings of the left bearing and the right bearing through threads. The clearance between the ball bearing and the ball bearing can be completely and automatically compensated by the tiny axial displacement of the axial thrust of the rotor, so that the aim of greatly prolonging the safe service life of the bearing is fulfilled.

Description

Long-life aviation bearing capable of completely and automatically compensating abrasion

Technical Field

The prior low, medium and high-end full-series bearings manufactured at home and abroad, in particular to high-end aviation bearings, no matter how good the quality of materials is selected by the international high-end bearing industry dominators, how magnificent the work results of system research experiment detection are, the technical level of precision machining manufacturing is high, and the abrasion among all parts of the bearings in high-speed rotation is unavoidable.

Background

Wear will result in a loss of dimensional accuracy of the part and the worn surface will exhibit pitting characteristics. Because of the large amount of heat generated by friction, the metal migration phenomenon between the two contact surfaces occurs, so that the abrasion surface is in phosphorus-like peeling. Under high stress or in the absence of lubricating oil, a large amount of frictional heat is generated between the two friction objects, which heat can sometimes bring the contact area locally to a molten state, so that instantaneous welding occurs, which in turn is torn off, with the consequence that intermetallic migration of the contact surface is caused, which wear is called adhesive wear.

The rolling elements are contacted with the roller path, and when the rolling elements are in extremely light contact load (or under excessive lubrication condition), the linear speeds of the contact points of the two contact elements are different due to the influence of inertia force, and at the moment, a sliding phenomenon, namely light load sliding, occurs between the two contact elements. The roller bearing has the advantages that the roller bearing has light-load slipping, friction and abrasion of a roller path, surface fatigue, surface damage of the roller path and the like, and the early damage is characterized by surface scratch and full-layer migration.

Rust is the damage caused by the chemical or electrochemical action of metallic materials and surrounding media, known as rust or corrosion. When rust occurs, black or brown rust spots or pits are formed on the surface, corrosion products appear, and the luster of the metal is destroyed. In bearings, a tribological corrosion phenomenon also occurs, which is characterized in its morphology: some pitting occurs on the contact surface. The formation mechanism is as follows: in the contact of the rolling bodies with the cage, the cage will undergo a slight plastic deformation under the effect of the forward pressure, so that a slight relative movement occurs between the two contact surfaces. The new metal surface formed by friction will be oxidized when subjected to the combined chemical, mechanical and thermal effects, and the oxide formed will be continuously accumulated and pressed against the surface layer. Also due to the high temperatures created by frictional heat, the lubricant will form aldehydes, ketones and carbonic acid, which will also react chemically with the material. Thus, fretting corrosion not only causes surface damage to the part but also reduces the contact fatigue strength of the part.

For high-speed rotating parts, as abrasion increases, mass eccentric vibration phenomenon, namely eccentric abrasion, is inevitable. Eccentric wear is a phenomenon in which the center of mass of a rotating component of a bearing is biased to one side during operation. Particularly, when the aircraft is in a maneuver of acceleration, deceleration, turning, ascending, descending … … and the like, because the rotor with certain mass rotates at a high speed, an inertial guidance acting force of the super-strong rotation gyro can be formed, and the acting force is superposed on one side of the larger deflection of the bearing, which occurs due to the mass center of the high-speed rotating part in operation, so that the eccentric wear acting force intensity and the eccentric wear are multiplied. Fatigue spalling occurs on the ball and raceway surfaces, and under the effect of this super-multiplied alternating stress, the maximum shear stress occurs at about 0.2mm from the surface depth. First, a first micro crack is formed from the weakest point of the material, and under the repeated action of the super-multiplied alternating stress, the crack is continuously and rapidly expanded and increased in value, and finally, the metal is peeled off. Once the main bearing of the aeroengine has obvious eccentric wear and fatigue peeling signs, serious safety accidents can occur at any time due to severe vibration of the engine to damage the bearing.

In summary, the abrasion of the bearing causes the loss of dimensional accuracy, adhesive abrasion, light-load slip, rust, eccentric abrasion and fatigue peeling of parts, and finally, the bearing can be damaged only by a few microcracks, so that serious safety accidents can occur at any time. Therefore, the service life and the safety of the aero-engine are improved, the strength, the toughness and the rust resistance of the bearing material and the precision of manufacturing and processing are improved to the greatest extent, the abrasion degree of the delayed bearing can be reduced, the safe service life of the bearing is prolonged, and the service life and the safety of the aero-engine are also improved.

Disclosure of Invention

In order to enable unavoidable bearing abrasion to obtain an instant, timely and fully automatic compensation effect, so that the safe service life of the bearing is greatly prolonged. The inventor collects several representative bearings in the industry for comparison, and the design thought and the working principle are described in detail in the attached drawings.

(1) Fig. 1 and fig. 2 are references to various parts of a bearing which are commonly used in the bearing industry. The parts of the bearing are respectively called an outer ring, an inner ring, a retainer, balls (rollers) and a retainer ring (a lubricating oil seal ring). Fig. 3 is a schematic diagram of an aviation bearing structure which is already disclosed in China. From this view, the cage and the rollers are formed as a single set of bearings, which, although of a complex and compact construction, are not relevant to the present technique.

(2) Fig. 4, fig. 5, fig. 6 and fig. 7. The invention is a schematic diagram of a long-life aviation bearing structure which can fully and automatically compensate abrasion. In detail, see fig. 6, the ball circumference length of the ball track AB arc segment=the ball track CD arc segment=the ball AD arc segment=the ball BC arc segment=1/4. The outer ring is formed by screwing and combining two symmetrical left and right bearing outer rings, namely the outer rings are respectively half, namely 1, 4 and 5 in the figure 5.

(3) Therefore, see fig. 4, fig. 5 and fig. 6 for details. The resultant of the stresses

Whether the direction is to press the AB raceway of the outer ring 1 in fig. 5 forwards or the resultant of these stresses +.>

The direction is to press the AB raceway of the outer ring 5 in fig. 5 backward. If the resultant force is->

In the forward direction, wear occurs between the AB circular arc raceway of the left outer ring 1, the balls and the DC circular arc raceway of the inner ring 6. If the resultant force is->

In the backward direction, wear occurs between the AB circular arc raceway of the outer ring 5 on the right side, the balls, and the DC circular arc raceway of the inner ring 5.

(4) The resultant of the stresses

The sum of the micro thickness of the surface layer worn by the DC circular arc roller path of the inner ring 6, the AB circular arc roller paths of the outer ring 1 and the outer ring 5 and the balls at the two sides can instantly and timely self-control the total amount of the worn thickness by the micro advance or the backward movement of the whole rotor bearing inner ring 6 along the axisThe motion complete compensation is successful. Therefore, the eccentric wear state can be timely avoided, and the safe service life of the main bearing of the aeroengine is greatly prolonged. In addition, no matter which direction is worn and stressed, the other end is not stressed, because of the effect of automatic complete compensation, a gap is formed between the inner ring roller path and the balls, no resultant force transmission exists, and only extremely weak extrusion friction force of the extremely weak ball centrifugal force to the outer ring roller path is remained. Naturally, this end will not wear out.

(5) For a system of mechanical parts with a horizontal distribution of the axis of rotation, there is little or no axial force to fix the movement. At this time, it is considered that a certain axial force is applied from the outside, such as a cooling fan, a connection with an external system helical gear, or an axial thrust … … is provided from an external system. The rotating mechanical component system generates certain axial acting force, and plays a role in completely and automatically compensating the abrasion of the bearing. For a system of mechanical parts with a vertically distributed axis of rotation, which is fixed without movement, the weight force that is originally present is naturally a downward axial thrust. For the design of the long-life bearing which can fully and automatically compensate the abrasion of the unidirectional thrust of the rotor all the time, the invention designs a simplified structure of screwing and combining the unilateral outer ring of the bearing and the lubricating oil sealing ring in a threaded manner, which is shown in fig. 8, for the bearing, and also has the function of the long-life bearing which can fully and automatically compensate the abrasion of the unidirectional thrust of the rotor. See fig. 8 for details, attention is directed to fig. 8 at 10.

(6) Detailed description is given of a structural schematic diagram of the long-life aviation bearing which is designed by the invention and can be fully and automatically compensated, in which the detailed description is shown in fig. 4, fig. 5, fig. 6 and fig. 7. There are five advantages, firstly, can lubricate, cool and clear up the piece comprehensively in time. Referring to fig. 6, the outer ring of the bearing is fixed and is next to the inner ring of the bearing rotating at high speed, so that the retainer and the balls are driven to rotate at high speed along with the inner ring, and the lubricating oil is driven to rotate at high speed. The centrifugal force of the liquid generated by the high-speed rotation of the lubricating oil forms that the liquid pressure of the lubricating oil at the oil filling hole E is far smaller than the pressure at the oil outlet hole F, and the pressure difference is enough to ensure that the lubricating oil is not lost. Even the oil filling hole becomes an oil suction hole. Similarly, the oil outlet hole also becomes an oil spraying hole, and a check ring (a lubricating oil sealing ring) is omitted. Secondly, the high-speed rotating lubricating oil pressure difference is more beneficial to timely discharging metal scraps with larger specific gravity generated by bearing abrasion out of the oil spraying hole, so that an engine oil filter can be conveniently cleaned in time, and the abrasion degree of the bearing is effectively reduced. Of course, for other high-end long-life bearings that do not require high lubrication, cooling, and cleaning of metal debris, oil injection holes and oil injection holes can be omitted. Referring to FIG. 6 in detail, the size of the space between AA and DD may be considered as the size of the lubricant reserve space. Thirdly, the ball and the inner ring roller paths are always in an anastomotic rolling state with tight thread joints, and a certain gap can be always kept between the ball and the retainer. Thus, the smoothness of the lubricating oil can be ensured, the abrasion between the balls and the retainer is avoided, and the lubricating and cooling performance can be improved. Fourthly, because the retainer comprises two concentric rings of big ring cover little ring, only use 4 thick enough oblique prism fixed connection between, so the retainer can wholly once only be by two-way mould from axial lead both sides opposite pressure just can forge successfully to improve intensity, toughness and safe life. Fifthly, the retainer adopts a combined ball structure, the space between the concentric rings of the two large rings and the small ring is divided into 4 ball string spaces, and 4 or more balls are respectively embedded into each string space, so that the abrasion between the balls and the retainer can be reduced, and the stress bearing strength of the bearing can be improved.

(7) In the same way, according to the design thought of the long-life bearing capable of completely and automatically compensating the abrasion, the bearing can be further expanded into a roller, an elliptic roller and a gear-shaped roller, and the roller can be replaced by the ball, as shown in figure 3.

Drawings

FIG. 1 is a bearing industry designation for various parts that make up a plain bearing;

FIG. 2 is a schematic view of the inner and outer race raceways and cage configuration of a roller bearing;

FIG. 3 is a schematic diagram of the structure of the parts of the inner and outer rings, the cage, the rollers, etc. of the specially customized aviation bearing disclosed in China;

FIG. 4 is a schematic structural view of a long life aero-bearing with fully automatic wear compensation according to the present invention;

FIG. 5 is an enlarged schematic view of a structural part of a long life aero-bearing of the present invention with fully automatic wear compensation;

FIG. 6 is a schematic view of the working principle of a structural part enlargement of a long life aero-bearing with fully automatic compensation of wear;

FIG. 7 is a schematic view of a cage and combination ball configuration of a long life aero-bearing with wear fully automatic compensation;

FIG. 8 is a schematic structural view of the unidirectional axial thrust of a long life bearing with wear that is fully self-compensating;

in fig. 5: 1. the bearing comprises a left outer ring of the bearing, a ball, a retainer, threads of the left outer ring and the right outer ring of the bearing are tightly combined and sealed, a right outer ring of the bearing, and a bearing inner ring. In fig. 6: the AB arc section is a bearing outer ring raceway, the CD arc section is a bearing inner ring raceway, the AD arc section and the BC arc section are holding movement spaces of the retainer and lubricating oil, the E position represents a lubricating oil filling hole, and the F position represents an oil outlet hole. In fig. 7: 7 is an inner ring retainer, 8 is an outer ring retainer, and 9 is an oblique prism-shaped fixed connection between the rings of the inner ring retainer and the outer ring retainer. In fig. 8: and 10 is a lubricating oil sealing ring of a one-way thrust bearing.

Detailed Description

The following describes specific embodiments of a long life aero-bearing with fully automatic wear compensation according to the present invention with reference to fig. 4, 5, 6 and 7:

1. the bearing outer ring is fixedly connected by the left bearing half outer ring and the right bearing half outer ring through screw threads. In order to prevent the outer ring from loosening and lubricating oil from leaking, the outer ring must be made into film strip or paint by adopting the material with high temperature resistance (> 500 ℃), good elasticity, high viscosity, good sealing property and stable chemical property which is not compatible with lubricating oil, and then wound or smeared on external thread and screwed. And if necessary, welding and sealing, and thoroughly sealing and fixing.

2. The bearing shown in fig. 6 is specially designed with the oil filling hole E and the oil outlet hole F, and is specially designed for extremely harsh lubrication, cooling and metal debris cleaning of main bearings of aeroengines and other high-end internal combustion engines and can greatly reduce the working range requirements of abrasion. The long-life (aviation) bearing without oil filling holes and oil outlet holes can be fully and automatically compensated, and can also be widely used as a high-end bearing in other high-end mechanical fields with low lubrication and cooling requirements. To replace the imported high-end bearings entirely.

Claims (6)

1. Novel wearing and tearing long-life aviation bearing that can complete automatic compensation compares its characterized in that with current high-end bearing, aeroengine main bearing: the outer ring of the bearing is formed by screwing and combining about half of the outer rings of the left bearing and the right bearing through threads; the clearance between the ball bearing and the ball bearing can be completely and automatically compensated by the tiny axial displacement of the axial thrust of the rotor, so that the aim of greatly prolonging the safe service life of the bearing is fulfilled.

2. The outer rings of the left side and the right side of the bearing are designed in a way of being connected with the sealing ring of lubricating oil, so that the whole die is convenient to forge successfully at one time, and the lubricating oil sealing ring which is specially matched with all bearings in the industry is omitted.

3. The inner ring and the outer ring of the ball retainer of the bearing can be sleeved together and consist of two concentric rings, and the two rings are fixedly connected by only 4 sufficiently thick oblique prisms, so that the retainer can be forged successfully by oppositely pressurizing two sides of a shaft axis through a bidirectional die integrally and once, and the strength, the toughness and the safe service life of the retainer can be improved.

4. The retainer adopts a bead-shaped combined ball structure, the space between the concentric rings of the two large rings and the small ring is divided into 4 ball strings, and 4 or more balls are respectively embedded into each string space, so that the abrasion between the balls and the retainer can be reduced, the number of the balls can be increased, and the stress bearing strength of the bearing can be improved.

5. Similarly, according to the design thought of the long-life bearing capable of completely and automatically compensating the abrasion, the design thought can be further expanded into the design thought that the balls can be replaced by rollers, elliptic rollers and even gear-shaped rollers, as shown in fig. 3.

6. For the design of the long-life bearing capable of completely and automatically compensating the abrasion of the unidirectional thrust of the rotor all the time, the invention specially designs a simplified structure of screwing and combining the unilateral outer ring of the bearing and the lubricating oil sealing ring by threads, and the bearing also has the function of the long-life bearing capable of completely and automatically compensating the abrasion generated by the unidirectional thrust of the rotor.

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