機械外文翻譯---關(guān)于軸承和軸的相關(guān)知識

1、<p><b>　　附錄一</b></p><p>　　Knowledge On The Bearings and Shaft</p><p>　　The bearings are fixed and reduce the load coefficient of friction in the process of mechanical transmissi

2、on components. Can also say that when the other parts on the shaft relative motion, used to reduce the friction coefficient in the process of power transfer and fixed the mechanical parts to maintain the position of the

3、shaft center. Bearings are important parts of modern machinery and equipment. Its main function is to support the mechanical rotating body to reduce the load coefficient of f</p><p>　　Nano Lake, Italy, found

4、 a Roman vessel discovered early instance of ball bearings. The wooden ball bearings are used to support the rotating desktop. Ship construction in 40 BC. It is said that Leonardo da Vinci in the 1500 or so, a ball beari

5、ng through description. , There is a very important point is the ball collision, causing additional friction between the ball bearings of all kinds of immature factors. But can put the ball into a small cage to prevent t

6、his phenomenon. The 17th century, Gal</p><p>　　In 1883, Friedrich Fischer proposed the idea of ??the use of suitable production machine grinding the same size, roundness accurate ball. This laid the foundati

7、on to create an independent bearing industry. In 1962, FAG the trademark has been modified and are still used today and become an integral part of the company in 1979.</p><p>　　In 1895, Henry Timken designed

8、 the first tapered roller bearings, three years later obtained a patent and the establishment of the Timken Company.</p><p>　　In 1907, SKF bearing factory Sven temperature Qwest designed the first modern sel

9、f-aligning ball bearings.</p><p>　　Study its role should be in terms of support, that the literal interpretation is used to bearing axis, but this is only part of its role in supporting its essence is to be

10、able to bear the radial load. Can also be understood that it is used to a fixed axis. A fixed axis so that it can only achieve rotation, and control of axial and radial movement. Motor without bearing the consequences is

11、 not work at all. Because the axis may be in any direction movement, the motor work requirements shaft only </p><p>　　Bearing the classification and described as follows:</p><p>　　Equipped with

12、a thin and long roller needle bearing (the length of the roller diameter of 3 to 10 times the diameter of generally not more than 5mm), therefore the radial structure is compact, its inner diameter and load capacity with

13、 other types of bearing the same minimum outside diameter, especially for supporting the results of radial installation dimensions restricted. needle bearing according to the use of different occasions, can be used witho

14、ut inner ring bearings or needle roller and ca</p><p>　　Aligning ball bearings Self-aligning ball bearings: two of the inner ring raceway and the raceway between the spherical outer ring, the assembly of the

15、 drum-shaped roller bearing. The outer ring raceway curvature center and bearing center line, and therefore have the same aligning and self-aligning ball bearings. Axis, the shell deflection occurs, you can automatically

16、 adjust to not increase the burden of bearing. Spherical roller bearings can bear radial load and axial load in two directions. A</p><p>　　Deep groove ball bearings imported bearings are mainly used for pure

17、 radial load, both radial and axial load. Only under pure radial load, the contact angle is zero. Performance of angular contact bearings, deep groove ball bearings with a larger radial clearance, and is subjected to hig

18、h axial load. Deep groove ball bearings, the friction coefficient is small, the limit speed is also high, especially in a large high-speed operation of the axial load conditions, deep groove ball bearings Thrust </p&g

19、t;<p>　　Aligning roller bearing is a spherical outer ring between the two raceways of the inner ring raceway assembly with drum-shaped roller bearings. Aligning roller bearing with two rollers, mainly exposed to t

20、he diameter of a load, but also able to withstand the axial load in either direction. High radial load capacity, especially suitable for work overload or vibration loads, but can not afford the pure axial load. This kind

21、 of bearing outer ring raceway is spherical shape, aligning performance is </p><p>　　Combination of bearing: a bearing formed by the combination of bearing structure in the above-mentioned two or more of rol

22、ling bearings. Such as needle roller and cylindrical roller thrust bearings, needle roller and thrust ball bearings, needle roller and angular contact ball bearings, etc..</p><p>　　Bearing life: under certai

23、n loads, the bearings in the number of revolutions or hours before pitting experienced, known as the bearing life.</p><p>　　The life of rolling bearings of the number of revolutions (or number of hours worke

24、d under a certain speed) is defined: In this life within the bearing, any bearing ring or rolling body on the initial fatigue damage (spalling or defect). But both in the laboratory tests or in actual use, can clearly se

25、e the appearance of the same bearing in the same working conditions, to differ materially from actual life. In addition to the bearing of several different definitions of "life", one of the so-call</p>&

26、lt;p>　　Due to differences in manufacturing precision, material uniformity, even if the same material, bearing the same batch of the same size, in the same working conditions, their longevity is not the same. In terms

27、of statistical life is 1 unit relative life expectancy of up to four units, the shortest was 0.1 to 0.2 units, the ratio of the longest and shortest life of 20 to 40 times.</p><p>　　The installation of beari

28、ngs:</p><p>　　Bearing installation, good or bad, will affect the accuracy, bearing life and performance. , The installation of the bearing, in accordance with the operating standards include the following it

29、ems, including the bearing installation.</p><p>　?、賑leaning bearings and related parts have been greased bearings and bilateral with </p><p>　　seals or dust cover, no need to clean before the in

30、stallation of the ring bearing.</p><p>　?、?Check the size and finishing conditions of the relevant parts of the</p><p>　　③ installation method bearing installation should be based on the nature

31、of the bearing structure, size, and bearing components with pressure should be directly added to a tight fit to the ferrule end surface, may not pass the pressure of the rolling element bearing installation generally use

32、 the following method: a press-fit bearing inner ring and shaft so tight fit, the outer ring and the bearing hole is loose with the available presses will be bearing the first pressure mounted on the shaft a</p>&

33、lt;p>　　④ bearing installation inspection</p><p>　?、?lubricant added to the installation of high-speed precision angular contact ball bearings, mainly for the load lighter, high-speed rotating occasions, t

34、he requirement of bearing high-precision, high speed, low temperature rise Low vibration and service life of high-speed precision angular contact ball bearings. Often for high-speed electric spindle bearing installed in

35、pairs, the key component parts of the inner surface of the grinding machine of high speed electric spindle. The main technical</p><p>　　Life of high-speed precision angular contact ball bearings have a great

36、 relationship with the installation, you should note the following: ① The bearings shall be installed in a clean, clean room, bearing carefully matching, bearing spacers to go through grinding, maintaining the premise of

37、 high-inside and outside the ring spacers, spacer parallelism should be controlled in 1um following; ② The bearings prior to installation should be clean, cleaning inner slopes upward, should be flexible and f</p>

38、<p>　　Tapered roller bearings, water pump bearing installation:</p><p>　?、?the installation of bearings: bearing must be installed in a dry, clean environment conditions. Before installation, carefully

39、 check the mating surface of the shaft and shell, the face of the convex shoulder trench and connection quality of surface processing. All match the connected surface must be carefully cleaned and remove the burrs, casti

40、ng raw surface must be in addition to net sand. Bearing installation should be preceded by cleaning with gasoline or kerosene, clean and dry before use,</p><p>　?、?bearing removal: Remove the bearing intend

41、to continue to use, you should use the appropriate removal tool. The demolition of the interference fit of the ring, only to increase the tension in the ring, never to allow demolition of the rolling elements, or the rol

42、ling element and raceway will be crushed.</p><p>　?、?bearing use of the environment: the use of location and conditions of use and environmental conditions to select the specifications of size, accuracy, and

43、 with the right bearing is the premise to ensure that the bearing life and reliability. Parts: tapered roller bearings are suitable to withstand the radial load mainly radial and axial joint load, usually paired to two s

44、ets of bearings used primarily in the car's front and rear wheel hub, active bevel gear, differential, reducer and transmiss</p><p>　　Axis function and type:</p><p>　　Axis is one of the impo

45、rtant parts in the machine, used to support the rotating parts of machinery.</p><p>　　Depending on the load bearing axis can be divided into the shaft, drive shaft and spindle three kinds. Shaft only transfe

46、r torque to withstand bending moments, such as the gear reducer shaft; drive shaft transmitting torque only not withstand the bending moment or bending moment is small. Such as automotive drive shaft; spindle is exposed

47、only to the moment rather than transmit torque, such as the axis of the rail vehicle, the front axle of the bicycle.</p><p>　　The shape of the shaft axis can be divided into: straight axle, crankshaft and fl

48、exible wire axis. Crankshaft is commonly used in reciprocating machinery. The flexible wire shaft wire layers close together by layers of flexible torque and rotational movement spread to any location commonly used in vi

49、brators and other devices. This chapter only study the direct axis.Shaft design, manufacturing process according to job requirements and to consider other factors, the appropriate choice of material</p><p>

50、　　Axis of the commonly used materials:</p><p>　　The axis of the material is often used carbon steel and alloy steel.</p><p>　　Carbon steel bearing 35,45,50 high-quality carbon structural steel h

51、as higher mechanical properties, more applications, of which the most widely used steel 45. In order to improve its mechanical properties, normalizing or quenching and tempering treatment. Unimportant, or by a smaller fo

52、rce axis, can be used such as Q235, Q275 carbon structural steel.</p><p>　　Alloy steel alloy steel has higher mechanical properties, but the price is more expensive, used for special requirements of the shaf

53、t. For example: the sliding bearings of high-speed shaft, commonly used in 20Cr, 20CrMnTi low-carbon alloy structural steel after carburizing can improve the wear resistance of the journal; generator rotor shaft in the h

54、igh temperature, high-speed and overload conditions. must have good high temperature mechanical properties, often to adopt 40CrNi, 38CrMoAlA alloy s</p><p>　　Axis rough general round bar or forgings, and som

55、etimes can be cast or ductile iron. For example, made of nodular cast iron crankshaft, camshaft, low cost, better vibration absorption, low sensitivity to stress concentration, good strength, etc..</p><p>　　

56、Axis of structural design:</p><p>　　The axis of the structure design is to make each part of the axis has a reasonable shape and size. Its main requirements are: 1) axis should be easy processing. Parts of t

57、he shaft to be easy disassembly (manufacture and installation requirements); 2) axis and the shaft parts have accurate position (location); 3) parts to firmly and reliably and relatively fixed (fixed); 4) to improve the

58、force situation, reducing the stress concentration.</p><p>　?、賂he manufacturing installation requirements</p><p>　　In order to facilitate the assembly and disassembly of the shaft parts, often t

59、he shaft made of the ladder. Split the box in the shaft, its diameter from the shaft end and gradually increases toward the middle. As shown above, can turn the gear, the sleeve, the left end bearings, bearing caps and p

60、ulley from the axis of the left end assembly and disassembly, and another from the right end of the assembly and disassembly of rolling bearings. Shaft parts is easy to install, should chamfer of the s</p><p&g

61、t;　　Axis grinding shaft section should wheel the more process slots; car threaded shaft section should be undercut.</p><p>　　Meet the requirements of the case, the axis of the shape and size should be simple

62、 in order to facilitate processing.</p><p>　?、赥he axis positioning of parts</p><p>　　Ladder shaft cross-section changes a place called the shaft shoulder, since the axial positioning of the role

63、. Shaft shoulder makes gear positioned on the shaft; shaft shoulder pulley positioning; shaft shoulder to the right end of the rolling bearing positioning.</p><p>　　Some parts rely on a set of simple positio

64、ning, such as above the left end of rolling bearings.</p><p>　?、跿he axis parts of the fixed</p><p>　　Axial fixation of the shaft parts, often with the shaft shoulder, sleeve, nut or shaft end of

65、 the retaining ring (also known as the plate) and other forms. Gear to achieve the axial two-way fixed. Gear by the axial force, right through the shaft shoulder, by the axis and shoulders in the rolling bearing inner ri

66、ng; left sleeve top in the rolling bearing inner ring. Can not use the sleeve or sleeves too long, we can use the round nut to be fixed. Pulley axial fixed retaining ring depend on the sh</p><p>　　Axis inten

67、sity calculated as follows:</p><p>　　Axis intensity shall be calculated according to the shaft bearing, using the appropriate method of calculation. The common axis strength calculation method has the follow

68、ing two:</p><p>　?、?Press the torsional strength calculation</p><p>　　This method applies only to withstand the torque of the drive shaft of accurate calculation, is well received by the bending

69、 moment and torque axis approximate calculation can also be used.Circular section shaft transmitting torque only, the strength condition.</p><p>　　Withstand both pass to turn short axis of the bending momen

70、t can also be used on the preliminary estimate of the diameter of the design formula:</p><p>　　In addition, the empirical formula can be used to estimate the diameter of the shaft. For example, in the genera

71、l reducer, high-speed input shaft diameter according to its associated motor shaft diameter D estimates, d = (0.8 ~ 1. 2) D; all levels of low-speed shaft of the gear center distance on the shaft diameter according to th

72、e same level a estimates, d = (0.3 0.4) a.</p><p>　?、?According to the synthetic strength of the bending and torsion</p><p>　　Single-stage cylindrical gear reducer design sketches, each symbol i

73、ndicates the length of the Dimensions. Obviously, when the parts laid out on the sketch, the role of location of the external load and support reaction force can be determined. Thus can be used for mechanical analysis of

74、 the shaft and draw the bending moment diagram and torque diagram. Then you can press the synthetic strength of the bending and torsion shaft diameter.</p><p>　　For the cross-section of the keyway should be

75、calculated shaft diameter increased by about 4%. Calculated shaft diameter greater than the shaft diameter of preliminary estimates of the structural design, that the strength of the chart axis is not enough, you must mo

76、dify the structural design; calculated shaft diameter less than the estimates of the structural design of shaft diameter, and the difference is not very generally subject to the structural design of the shaft diameter.F

77、or general-pur</p><p>　　Axis by the bending moment will produce a bending torque role will have the torsional deformation. If the shaft stiffness is not enough, it will affect the normal work of the axis. Fo

78、r example, the deflection of the rotor shaft is too large, will change the rotor and stator gap and affect the performance of the motor. Another example is the rigidity of the machine spindle is enough, it will affect th

79、e machining accuracy. Therefore, in order so that the axis is not enough stiffness and failure, m</p><p>　　Axis of the concept of critical speed:</p><p>　　Uneven due to structural asymmetries of

80、 the rotary parts, materials, processing errors and other reasons, to make the rotation center of gravity is precisely located in the geometric axis, it is almost impossible. In fact, the center of gravity and the geomet

81、ric axis generally total a slight eccentricity, and thus the centrifugal force generated when rotating the axis by the interference of cyclical loading.</p><p>　　Axis suffered external frequency axis since t

82、he vibration frequency of the same operation will be unstable vibration occurs, a phenomenon known as the resonance of the shaft. Resonance when the shaft speed is called the critical speed. If the shaft speed is stuck n

83、ear the critical speed, the axis of deformation increases rapidly, as well as the axis, the extent of the damage or even the whole machine. Therefore, the important, especially high-speed axis to calculate the critical s

84、peed, and shaft</p><p>　　The shaft critical speed, the lowest one called the first critical speed, the remaining second, third ......</p><p>　　Speed ??is below a first critical speed axis is cal

85、led the rigid shaft; more than the first critical speed axis is called the flexible shaft.</p><p>　　Slender axis machining process characteristics:</p><p>　　(1) slender shaft turning the process

86、 characteristics</p><p>　　Slender shaft rigidity is poor, turning fashion folder properly, it is easy because of the role of cutting force and gravity bending deformation,</p><p>　　Vibration, th

87、us affecting the machining accuracy and surface roughness.</p><p>　　The slender shaft of the thermal diffusivity of poor performance, the effect of cutting heat, will produce quite a large linear expansion.

88、If the two ends of the shaft to a fixed support, the workpiece due to the elongation of the top bend.</p><p>　　The longer axis, a walk the knife for a long time, tool wear, thus affecting the geometry of the

89、 precision of the parts.</p><p>　　Car slender shaft supporting the workpiece with the tool holder, the two supporting block inappropriate parts pressure will affect the machining accuracy. If the pressure is

90、 too small or do not touch, it does not work, you can not improve the stiffness of the parts; if the pressure is too large, the parts are pressed to the lathe tool, the cutting depth increases, the car out of the diamete

91、r is small, continue to move with the turret bearing block support in the small-diameter cylindrical bearin</p><p>　?、?slender shaft advanced turned France - reverse pass turning France</p><p>　

92、　Reverse pass turning schematic of the method, this method is characterized by:</p><p>　　Slender shaft of the left wrapped around a circle of wire, use of the clamping jaw self centering chuck, reduce the co

93、ntact area of ??the workpiece chuck can freely adjust its location to avoid clamping the formation of the bending moment in the process of cutting deformation occurred not chuck folder death of the internal stress.</p

94、><p>　　Tailstock changed elastic top, when the workpiece by the cutting heat line expansion elongation top can automatically back to avoid deformation caused by thermal expansion.Using three bearing block with

95、 the turret, in order to improve the workpiece rigidity and stability of the axis, to avoid the "bamboo" shape.</p><p>　　Change the cutting direction, so that the saddle move to the tailstock spind

96、le box, so that the workpiece tension, less elastic bending deformation.</p><p>　　The rough material of the shaft parts</p><p>　　Shaft parts blank:Shaft parts can be used according to requireme

97、nts, type of production, equipment condition and structure, selection of bar stock, forgings and other rough forms. The outer diameter difference between the small axis, generally bar; outer diameter difference between t