Tapered roller bearing rotation precision determination method

Abstract

A tapered roller bearing rotation precision determination method comprises the following steps: establishing a mathematical model reflecting the jerk value of a tapered roller bearing, measuring related parameters when an inner ring and an outer ring of the tapered roller bearing are not fitted, and substituting the related parameters into the mathematical model to obtain the jerk value of the tapered roller bearing. And judging the rotation precision of the tapered roller bearing according to the radial run-out amount and the axial run-out amount of the tapered roller bearing. The method is used for rapidly and accurately judging the rotation precision of the tapered roller bearing.

Description

Technical Field

[0001] The invention relates to the technical field of bearing accuracy detection, in particular to a method for determining the rotation accuracy of a tapered roller bearing. Background Art

[0002] Tapered roller bearings can bear multiple loads such as radial, axial and bending moment at the same time, and have the advantages of high stiffness, load-bearing capacity, long life, high stability, etc., and are widely used in wind power generation, high-speed rail axle boxes and other equipment. In this field, the research on the rotation accuracy of rolling bearings is mainly focused on cylindrical roller bearings and ball bearings, while the geometric relationship of tapered roller bearings is complex, and the rotation accuracy analysis is almost blank. The rotation accuracy of tapered roller bearings (measured by axial runout and radial runout) needs to be measured after assembly. Figure 1 As shown, the inner ring is fixed on a specific device to ensure that the roller is in contact with the raceway. Indicator 1 (micrometer) is placed on the outer surface of the outer ring and as close to the middle of the outer ring raceway as possible. The change of indicator 1 after one rotation of the outer ring is the radial runout; the reference end face of the outer ring is fixed on a specific device to ensure that the roller is in contact with the raceway. Indicator 2 (micrometer) is placed on the reference end face of the inner ring. The change of indicator 2 after one rotation of the inner ring is the axial runout.

[0003] The precision detection of the above tapered roller bearings lacks a corresponding mathematical model. The inner and outer rings need to be fitted together for measurement, and the process is relatively cumbersome and complicated. Summary of the invention

[0004] The present invention aims to provide a method for determining the rotation accuracy of a tapered roller bearing, so as to quickly and accurately determine the rotation accuracy of the tapered roller bearing.

[0005] In order to solve the above technical problems, the specific scheme adopted by the present invention is: a method for determining the rotation accuracy of a tapered roller bearing, establishing a mathematical model reflecting the runout of a tapered roller bearing, measuring relevant parameters when the inner ring and outer ring of the tapered roller bearing are not assembled, substituting the relevant parameters into the mathematical model to obtain the runout of the tapered roller bearing, and determining the rotation accuracy of the tapered roller bearing based on the radial runout and axial runout of the tapered roller bearing.

[0006] Preferably, the mathematical model includes K reflecting the radial runout of the tapered roller bearing and S reflecting the axial runout of the tapered roller bearing.

[0007] K=K ri +K re +K Dw ,

[0008] Among them, K ri is the radial variation of the inner ring raceway, K iTo control the geometric accuracy of the inner ring wall thickness variation, β is the angle between the inner ring raceway generatrix and its centerline; K re is the radial variation of the outer ring raceway, K e To control the geometric accuracy of the outer ring wall thickness variation, α is the nominal contact angle of the tapered roller bearing; K Dw is the effect of roller error on radial variation, K Dw =max(BD)-min(BD), BD=ABcos(∠ABD), where point A and point B are the two opposite endpoints on the large end of the roller, AB=D w , draw an axial horizontal line along point A, draw a radial vertical line along point B, and D is the intersection of the horizontal and vertical lines;

[0009] S = max(T) - min(T),

[0010] Where T is the assembly height of the roller, T = S BO -S EO +a0, a0 is the root width of the large rib, S BO =BO cosβ, O is the intersection of the inner ring raceway, outer ring raceway and the extension of the roller centerline, E is the nominal small inner diameter of the outer ring;

[0011] The relevant parameter K is measured when the inner ring and outer ring of the tapered roller bearing are not assembled. e , K i , E, a0 and D w .

[0012] Preferably, K e and K i The inner ring and outer ring are measured by a micrometer respectively. The corresponding ring is placed in a fixed device, and the needle of the micrometer is placed in the middle of the raceway. The needle movement of the ring is K. e and K i .

[0013] The present invention establishes a mathematical model for the rotation accuracy of a tapered roller bearing. After separately measuring the relevant parameters of the ring and the roller, it can be determined whether the rotation accuracy of the complete bearing meets the technical requirements, making the determination of the rotation accuracy of the tapered roller bearing simple, convenient and accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of a measuring method for measuring the rotation accuracy of a tapered roller bearing in the prior art;

[0015] Figure 2 Indicates the geometric accuracy of controlling the variation of outer ring wall thickness;

[0016] Figure 3 To control the geometric accuracy of the inner ring wall thickness variation;

[0017] Figure 4 Schematic diagram of the geometric relationship between the roller and raceway of a tapered roller bearing;

[0018] Figure 5 Schematic diagram of the spatial geometric relationship of the rollers of a tapered roller bearing. DETAILED DESCRIPTION

[0019] Figure 2 Indicates the geometric accuracy of controlling the outer ring wall thickness variation, K e Indicates. α is the nominal contact angle of the bearing; Figure 3 In order to control the geometric accuracy of the inner ring wall thickness variation, K i β is the angle between the inner ring raceway generatrix and its centerline.

[0020] Figure 4 is the geometric relationship between the roller and the raceway, where MN is the center line of the roller.

[0021] Radial variation of the inner ring raceway

[0022]

[0023] Radial variation of the outer ring raceway

[0024]

[0025] The angle between MN and BC is It represents the angle between the roller generatrix and its centerline. If ∠BMN is 90°, then

[0026]

[0027] In order to find out the influence of roller error on radial variation, the spatial geometric relationship of the roller is as follows: Figure 5 As shown, Figure 5 A and B represent the endpoints of the roller's big end; C represents the endpoint of the roller's small end. Draw a radial vertical line along point B and an axial horizontal line along point A. D is the intersection of the vertical and horizontal lines. MN is the intersection of the roller centerline with the roller's big end and small end, respectively. O is the intersection of the inner ring raceway, outer ring raceway, and the extension of the roller centerline. Draw an axial horizontal line along point C and a radial vertical line along point B. F is the intersection of the horizontal and vertical lines.

[0028] Depend on Figure 5 From the geometric relationship in, we can see that ∠BCF=β;∠CFB=90°;∠CBF=90°-β;

[0029] Therefore, ∠ABD=180°-∠CBF-∠MBC

[0030] Then, BD = AB cos (∠ABD)

[0031] according to Figure 1 ,in

[0032] AB=D w

[0033] Measure the D of the roller used W The maximum and minimum values ​​of BD are obtained, and the influence of roller error on radial variation is

[0034] K Dw =max(BD)-min(BD)

[0035] Radial runout is expressed as

[0036] K=K ri +K re +K Dw

[0037] Figure 5 In the figure, the axial distance from point B to point O is

[0038] S BO =BO cosβ

[0039] in

[0040]

[0041] Figure 1 As shown, the axial distance from the reference end face of the bearing outer ring to point O is expressed as

[0042]

[0043] Based on the geometric relationship, the axial runout can be represented by the change in assembly height.

[0044] S = max(T) - min(T)

[0045] The assembly height T is

[0046] T=S BO -S EO +a0

[0047] Where a0 represents the root width of the large rib.

[0048] Taking the 30319 bearing as an example, the above model is verified. The inner and outer rings of the bearing are measured, and 5 points are randomly selected in the circumferential direction of the ring. The measurement results are shown in Table 1. Table 1

[0049] K i , K e Obtained from the difference between the lowest point of the needle and the measuring point. Place the ring in a fixed device, place the needle of the micrometer in the middle of the raceway, and the needle movement amount of the ring is Ke and Ki when it rotates one circle. Figure 2 , take the outer cylindrical surface of the outer ring as the reference, rotate one circle, and get Ke; according to Figure 3 , take the inner cylindrical surface of the inner ring as the reference, rotate one circle, and get Ki. The roller needs to be selected, so D W The value consistency is high, and the appropriate roller is selected through the roller standard parts. is 1°, α is 10.5°, and β is 8.5°.

[0050] The calculated K is 0.0071mm and S is 0.012mm. The calculated results are consistent with the test results of the complete set of bearings.

Claims

1. A method for determining the rotation accuracy of a tapered roller bearing, characterized in that: A mathematical model reflecting the runout of a tapered roller bearing is established, and relevant parameters are measured when the inner ring and outer ring of the tapered roller bearing are not assembled. The relevant parameters are substituted into the mathematical model to obtain the runout of the tapered roller bearing, and the rotation accuracy of the tapered roller bearing is judged by the radial runout and axial runout of the tapered roller bearing.

2. A method for determining the rotation accuracy of a tapered roller bearing according to claim 1, characterized in that: The mathematical model includes K reflecting the radial runout of the tapered roller bearing and S reflecting the axial runout of the tapered roller bearing. K=K ri +K re +K Dw , Among them, K ri is the radial variation of the inner ring raceway, K i To control the geometric accuracy of the inner ring wall thickness variation, β is the angle between the inner ring raceway generatrix and its centerline; K re is the radial variation of the outer ring raceway, K e To control the geometric accuracy of the outer ring wall thickness variation, α is the nominal contact angle of the tapered roller bearing; K Dw is the effect of roller error on radial variation, K Dw =max(BD)-min(BD), BD=AB cos(∠ABD), where point A and point B are the two opposite endpoints on the large end of the roller, AB=D w , draw an axial horizontal line along point A, draw a radial vertical line along point B, and D is the intersection of the horizontal and vertical lines; S = max(T) - min(T), Where T is the assembly height of the roller, T = S BO -S EO +a0, a0 is the root width of the large rib, S BO =BO cosβ, O is the intersection of the inner ring raceway, outer ring raceway and the extension of the roller centerline, E is the nominal small inner diameter of the outer ring; The relevant parameter K is measured when the inner ring and outer ring of the tapered roller bearing are not assembled. e , K i , E, a0 and D w .

3. A method for determining the rotation accuracy of a tapered roller bearing according to claim 2, characterized in that: K e and K i The inner ring and outer ring are measured by a micrometer respectively. The corresponding ring is placed in a fixed device, and the needle of the micrometer is placed in the middle of the raceway. The needle movement of the ring is K. e and K i .

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