Method and apparatus for measuring diagonal line of raceway of inner ring of a spherical roller bearing

Abstract

The application provides a method and an instrument for measuring diagonal line of inner ring raceway of a self-aligning roller bearing, and belongs to the field of measuring devices. The instrument comprises a measuring table, a fixed rod and a column are arranged above the measuring table, a floating rod is hingedly arranged on the column, the opposite sides of the floating rod and the fixed rod are both provided with a cylindrical surface which is vertical to the axis and is used for forming point contact with a measured object, one of the fixed rod and the column is provided with a position adjusting structure which can adjust the distance between the fixed rod and the floating rod, the floating rod is provided with an elastic member which is used for abutting against the measured object, and a measuring table is further arranged on the column, a detection end of the measuring table is in contact with the side of the floating rod which is away from the fixed rod so as to detect the floating amount of the floating rod. The method is implemented by using the above instrument. The method provided by the application can more accurately measure the diagonal line size of the inner ring raceway of the self-aligning roller bearing, is simple to operate, and is suitable for process detection.

Description

Technical Field

[0001] This invention belongs to the field of measuring devices, and in particular relates to a method and instrument for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing. Background Technology

[0002] Bearing clearance directly affects bearing life, temperature rise, vibration, and noise, and is a key performance parameter and a critical item in finished product measurement. Bearing assembly involves selecting and matching the inner ring, outer ring, and rolling elements according to their tolerances to ensure that the product clearance is within the standard requirements.

[0003] For self-aligning roller bearings, the clearance is equal to the outer ring raceway diameter minus the inner ring raceway diagonal dimension minus twice the roller diameter. Therefore, the inner ring raceway diagonal dimension has a direct impact on clearance control. Measuring the diagonal dimensions of the two inner ring raceways is an important prerequisite for grouping and matching the inner ring raceways and achieving the theoretical fit of self-aligning roller bearings.

[0004] See Appendix for the cross-sectional structure of the inner ring of the self-aligning roller bearing. Figure 1 The diagonal dimension *di* of the inner ring raceway in a self-aligning roller bearing refers to the distance between two points on the raceway surface where the line connecting the centers of curvature on opposite sides of the two raceways intersects. The diagonal dimension *di* of the inner ring raceway is influenced by the positions of the centers of curvature O1 and O2, as well as the raceway curvature Ri.

[0005] In actual machining and inspection processes, the diagonal dimension of the inner ring raceway is difficult to measure effectively due to the unique shape of the inner ring of self-aligning roller bearings. Conventional bearing testing instruments cannot perform this measurement effectively, often requiring large-scale equipment such as coordinate measuring machines (CMMs). This process is time-consuming, inefficient, and requires a constant-temperature environment, making it unsuitable for production, especially for inter-process inspection. Therefore, measuring the diagonal dimension of the inner ring raceway of self-aligning roller bearings has become a significant challenge for bearing manufacturers.

[0006] The existing literature "Measurement of the Diagonal of the Inner Ring Raceway of Extra-Large Self-Aligning Ball and Self-Aligning Roller Bearings" (Tian Lin, Luo Guibin, Cui Chuanrong. Measurement of the Diagonal of the Inner Ring Raceway of Extra-Large Self-Aligning Ball and Self-Aligning Roller Bearings [J]. Metalworking (Cold Working), 2015(12):43-44.) discloses a measuring instrument and a measuring method that can directly measure the diagonal of the inner ring raceway of a self-aligning roller bearing. The instrument has a left support and a right support mounted on a long tube and whose position is adjustable. A left ball holder is slidably set on the left support for pressing against one of the inner ring slides. A right ball seat is set on the right support and is driven to cooperate with the measuring end of the measuring instrument and can slide along the right support.

[0007] The operating method of this instrument is as follows: Place the calibrated standard sample ring (selected from the machined bearing inner ring and calibrated by metrology personnel) on the platform, place the installed instrument on the standard sample ring, adjust the left and right ball supports so that the steel balls on the two ball supports are at the bottom of the grooves of the two raceways, and align the measuring dial indicator; then place the adjusted instrument on the inner ring to be measured and measure. During the measurement process, fix the left support by hand, rotate the right support, read the maximum value of the measuring dial indicator swing, and compare this value with the value measured by the standard sample ring to obtain the diagonal dimension deviation of the inner ring to be measured.

[0008] This instrument compares the diagonal dimensions of the inner ring to be measured with those of a standard sample ring. It obtains the diagonal dimension of the inner ring raceway by adding the measured dimensional deviation to the diagonal dimension of the standard sample ring, and then compares it with a set range to determine if the diagonal dimension of the inner ring raceway meets the processing requirements. However, this instrument has unavoidable errors, resulting in poor measurement accuracy. Specifically, due to processing reasons, the position of the raceway curvature center and the raceway curvature on different self-aligning roller bearing inner rings inevitably deviate. This means that during the measurement process, most inner rings being measured cannot achieve contact between the steel ball and the bottom of the raceway groove. This also means that most measurement positions are not at the actual position of the inner ring raceway diagonal, resulting in inaccurate measurement results. Summary of the Invention

[0009] The purpose of this invention is to provide a method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing, so as to solve the technical problem of inaccurate measurement of the diagonal dimension of the inner ring raceway of a self-aligning roller bearing in the prior art.

[0010] The purpose of this invention is to provide an instrument for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing, so as to apply the above-mentioned method and solve the corresponding technical problems.

[0011] To achieve the above objectives, the technical solution of the method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing provided by this invention is as follows: A method for measuring the diagonal of the raceway of a self-aligning roller bearing is disclosed. The instrument used in this method comprises two rods with parallel cylindrical axes. The two rods serve as a fixed rod and a floating rod that can float along their alignment. Before actual measurement, the instrument is adjusted using a standard part to ensure that the initial distance between the floating rod and the fixed rod is equal to the corresponding dimension of the standard part. During actual measurement, the inner ring to be measured is placed between the two rods, and the two raceways of the inner ring are brought into point contact with the cylindrical surfaces of the two rods. The axis of the inner ring to be measured is kept perpendicular to the cylindrical axes of the two rods, and the inner ring is swung so that the line connecting the contact points coincides with the diagonal at a certain moment. When the line connecting the contact points coincides with the diagonal, the distance between the two contact points is minimized and can represent the diagonal dimension. The deviation between the inner ring to be measured and the corresponding dimension of the standard part is obtained by reading the floating amount of the floating rod, and then the diagonal dimension of the inner ring to be measured is calculated.

[0012] The beneficial effects are as follows: The method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing provided by this invention is a pioneering invention. This method utilizes the cylindrical surfaces on the floating rod and the fixed rod as the two contact points between the instrument and the inner ring being measured during the measurement process. The advantage of this design is that, as long as the axes of the cylindrical surfaces of the two rods remain parallel, the line connecting the contact points after the two cylindrical surfaces contact the two raceways of the inner ring being measured will necessarily pass through the axis of the inner ring. This reduces a variable in the measurement process; only the angle between the line connecting the contact points and the axis of the inner ring being measured needs to be adjusted during the measurement, reducing the difficulty of aligning the line connecting the contact points with the diagonal of one of the raceways of the inner ring being measured. Furthermore, during the measurement process, the inner ring being measured will swing back and forth with its axis perpendicular to the axis of the cylindrical surface of the rod. The probability that the line connecting the contact points coincides with the diagonal of one of the raceways of the inner ring being measured increases with the number of swings. After multiple swings, the floating amount of the floating rod is read when the distance between the two contact points is the smallest. Then, the measured value of the diagonal dimension of the inner ring hob is calculated by combining the floating amount with the corresponding dimensions of the standard part. This allows the measured value to be closest to the actual dimension of the diagonal of the raceway of the inner ring being measured, thus improving the accuracy of the measurement.

[0013] As a further improvement, a cylindrical object is selected as the standard part, and the outer diameter of the standard part is matched with the design value of the diagonal dimension of the inner raceway being measured. During the instrument adjustment process, the standard part is placed between the two rods and the outer circumference of the standard part is pressed against the cylindrical surfaces of the two rods to form point contact. The axis of the standard part is kept perpendicular to the axis of the cylindrical surfaces of the two rods, and the standard part is swung so that the line connecting the contact points can coincide with the diameter of the standard part at a certain moment. When the line connecting the contact points coincides with the diameter, the distance between the two contact points is the smallest and can represent the diameter of the standard part.

[0014] The beneficial effects are: standard parts with a cylindrical outline are easier to manufacture and their machining accuracy is easier to control, resulting in standard parts with uniform diameter dimensions throughout, which is convenient for use. Moreover, the calibration operation of these standard parts is easier, and the calibration results are more accurate, which can further reduce measurement errors.

[0015] As a further improvement, the outer diameter of the standard part is located between the minimum and maximum limit dimensions of the diagonal of the inner ring being measured.

[0016] The beneficial effect is that the deviation between the outer diameter of the standard part and the actual raceway diagonal size of the inner ring being measured is small, which makes the state of the instrument when measuring the standard part similar to that when measuring the inner ring being measured, thus eliminating the measurement error caused by the different working states of the instrument.

[0017] As a further improvement, the instrument has a measuring platform. Before measurement, the upper surface of the measuring platform is adjusted to be horizontal. At this time, the cylindrical axes of the fixed rod and the floating rod are vertical. During the instrument adjustment process, a standard pad is first placed on the measuring platform. Then, the axis of the standard part is placed horizontally on the standard pad and its outer circumference is in contact with the upper surface of the standard pad. The height of the standard pad is equal to half of the outer diameter of the middle flange of the inner ring to be measured minus the diagonal. In the actual measurement process, the axis of the inner ring to be measured is placed horizontally on the standard pad and its outer circumference is in contact with the upper surface of the standard pad.

[0018] The beneficial effects are: by using standard blocks to elevate the standard part, the contact position between the standard part and the floating rod is made approximately the same as the contact position between the inner ring being measured and the floating rod. This ensures that the instrument operates in the same state when measuring the standard part and the inner ring being measured, reducing measurement errors. Especially when the floating rod's floating mode is oscillating, the identical contact position reduces the influence of the initial tilt angle of the floating rod, thereby achieving higher measurement accuracy.

[0019] As a further improvement, during the instrument adjustment process, first adjust the floating rod to a vertical position, then move the fixed rod and the standard part so that the standard part contacts the floating rod, which is already in a vertical position, and also contacts the fixed rod. At this time, lock the fixed rod, and then measure the outer diameter of the standard part.

[0020] The beneficial effect is that by setting the fixed rod to an adjustable position, it is easier to measure the diagonal of the hob on the inner ring of self-aligning roller bearings of different specifications, thus providing better versatility.

[0021] As a further improvement, when the floating rod is in a vertical state, the preload of the measuring gauge is greater than half of the difference between the minimum and maximum limit dimensions of the inner raceway diagonal, while being less than or equal to half of the measuring gauge's range.

[0022] The beneficial effect is that, since the diagonal dimension of the inner raceway being measured may be larger or smaller than the corresponding dimension of the standard part, adjusting the preload in the above manner can enable the measuring instrument to measure both positive and negative deviations.

[0023] To achieve the above objectives, the technical solution of the self-aligning roller bearing inner ring raceway diagonal measuring instrument provided by the present invention is as follows: An instrument for measuring the diagonal of the raceway of a self-aligning roller bearing inner ring includes a measuring platform for placing a standard part or the inner ring to be measured. A fixed rod and a column are arranged above the measuring platform. A floating rod is hinged to the column. The rotation center axis of the floating rod is horizontal and perpendicular to the arrangement direction of the floating rod and the fixed rod. The opposing sides of the floating rod and the fixed rod are provided with cylindrical surfaces with vertical axes for forming point contact with the object being measured. One of the fixed rod and the column is equipped with an adjustment structure that can adjust the distance between the fixed rod and the floating rod. The floating rod is equipped with an elastic element for pressing it against the object being measured. A measuring gauge is also provided on the column. The measuring end of the measuring gauge contacts the side of the floating rod away from the fixed rod to detect the floating amount of the floating rod.

[0024] The beneficial effects are as follows: The self-aligning roller bearing inner ring raceway diagonal measuring instrument provided by this invention is a pioneering invention. This instrument is used to implement the aforementioned method for measuring the diagonal of the self-aligning roller bearing inner ring raceway. During use, both the standard part and the inner ring to be measured are placed horizontally on the measuring table. After adjusting the instrument using the method described above, the actual measurement is performed. The floating rod of this instrument uses a rotating mechanism to achieve floating. Compared to a sliding mechanism, the rotating mechanism allows for the use of high-precision bearings to eliminate rotational clearance, while the sliding mechanism suffers from difficulty in eliminating sliding fit clearance, resulting in insufficient measurement accuracy. One of the fixed rod and the column is equipped with an adjustment mechanism to adjust the distance between the fixed rod and the floating rod, thus facilitating the adaptation to inner rings of different specifications of self-aligning roller bearings. Moreover, the instrument has a simple structure, high reliability, and is suitable for use in production workshops.

[0025] As a further improvement, the adjustment structure includes an adjustment slot on the measuring table, the extension direction of which is parallel to the arrangement direction of the fixed rod and the floating rod, and the lower end of the fixed rod is fixedly installed in the adjustment slot by fasteners so that the position of the fixed rod is adjustable.

[0026] The beneficial effects are: the adjustment groove provides a guiding and locking basis for the position adjustment of the fixed rod, which is convenient to operate and has a simple structure.

[0027] As a further improvement, the fixing rod includes a vertically extending main rod body and a horizontally extending mounting rod body connected to the lower end of the main rod body. The end of the mounting rod body away from the main rod body faces away from the floating rod, and this end is connected to a guide connecting block installed in the adjustment slot, so that the adjustment slot can be outside the position adjustment range of the main rod body.

[0028] The beneficial effect is that when the inner ring being measured is placed on the measuring platform, only the outer circumference of its central retaining edge contacts the platform, resulting in a small contact area. If the adjustment slot extends to this point, it will affect the stability of the inner ring being measured. Placing the adjustment slot outside the position adjustment range of the main rod body allows it to avoid the placement area of ​​the inner ring being measured, thus not affecting its placement.

[0029] As a further improvement, the portion of the floating rod below the rotation center axis is the contact portion for contacting the standard part or the inner ring being measured, while the measuring end of the measuring instrument contacts the portion of the floating rod above the rotation center axis.

[0030] The benefits are twofold: firstly, this setting allows the measuring instrument to be positioned higher, making it easier for operators to read the readings; secondly, it allows for more space around the part below the rotation center of the floating rod, facilitating operation. Attached Figure Description

[0031] Figure 1 A sectional view of the inner ring of an existing self-aligning roller bearing; Figure 2 This is a front view of an embodiment of the self-aligning roller bearing inner ring raceway diagonal measuring instrument of the present invention; Figure 3 This is a top view of an embodiment of the self-aligning roller bearing inner ring raceway diagonal measuring instrument of the present invention; Figure 4 This is a front view of another embodiment of the self-aligning roller bearing inner ring raceway diagonal measuring instrument of the present invention; Figure 5 This is a front view of the instrument being adjusted in Embodiment 2 of the method for measuring the diagonal of the inner ring raceway of the self-aligning roller bearing in this invention; Figure 6 This is a top view of the instrument being adjusted in Embodiment 2 of the method for measuring the diagonal of the inner ring raceway of the self-aligning roller bearing in this invention; Figure 7 This is a front view of the instrument being adjusted in Embodiment 3 of the method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing in this invention.

[0032] Explanation of reference numerals in the attached figures: 1. Inner ring to be measured; 101. Raceway; 102. Center flange; 2. Standard parts; 3. Standard pads; 4. Measuring table; 41. Adjustment groove; 5. Fixing rod; 51. Main rod body; 52. Mounting rod body; 53. Connecting block; 6. Column; 7. Floating rod; 71. Protrusion; 8. Measuring gauge; 9. Rod holder; 10. Gauge holder; 11. Screws. Detailed Implementation

[0033] The present invention will be further described in detail below with reference to the embodiments.

[0034] A specific embodiment of the self-aligning roller bearing inner ring raceway diagonal measuring instrument provided by the present invention: See appendix Figure 1 and attached Figure 2 The instrument for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing includes a measuring platform 4, a fixed rod 5, a column 6, a floating rod 7, and a measuring gauge 8. The upper surface of the measuring platform 4 is flat and must be adjusted to a horizontal position during use. The column 6 and the fixed rod 5 are both located above the platform and extend vertically. The floating rod 7 is hinged to the column 6, and the measuring gauge 8 is fixedly mounted on the column 6.

[0035] The area between the fixed rod 5 and the floating rod 7 is used to place the inner ring 1 or the standard part 2 to be measured. During the actual measurement process, the fixed rod 5 remains stationary as the measurement reference. The floating rod 7 has a certain amount of floating according to the size deviation of the object being measured. By measuring this amount of floating, the size deviation of different objects being measured can be obtained.

[0036] The fixed rod 5 is equipped with an adjustment mechanism, making its position adjustable. The main purpose of this design is to facilitate adjusting the initial distance between the fixed rod 5 and the floating rod 7 according to the size of the object being measured during instrument adjustment. The adjustment mechanism includes an adjustment slot 41 on the measuring stage 4. The extension direction of the adjustment slot 41 is parallel to the arrangement direction of the fixed rod 5 and the floating rod 7. The lower end of the fixed rod 5 is fixedly installed in the adjustment slot 41 by fasteners such as screws 11. When the position of the fixed rod 5 needs to be adjusted, the fasteners are loosened, and the operator manually moves the fixed rod 5. After the fixed rod 5 is moved to the appropriate position, the fasteners are locked to keep the fixed rod 5 fixed.

[0037] In this embodiment, the fixing rod 5 is vertical, and a connecting block 53 is located at the lower end of the fixing rod 5. The connecting block 53 is located in the adjusting groove 41 and is guided and engaged with the adjusting groove 41. The fasteners mentioned above are installed on the connecting block 53. The cross-sectional shape of the adjusting groove 41 is inverted T-shaped. The cross-sectional shape of the connecting block 53 is adapted to the cross-sectional shape of the adjusting groove 41. Two screws 11 are vertically threaded through and connected to the connecting block 53. The heads of the screws 11 face upwards and the shanks face downwards. After tightening the screws 11, the shanks press against the bottom surface of the adjusting groove 41, thereby maintaining a certain abutting contact force between the connecting block 53 and the adjusting groove 41, thus fixing the fixing rod 5. To avoid the adjustment groove 41 affecting the placement stability of the inner ring 1 being measured, the length of the adjusting groove 41 can be shortened.

[0038] In other embodiments, see Appendix Figure 4Alternatively, the fixing rod 5 can be designed as an L-shape. In this case, the fixing rod 5 includes a vertically extending main rod body 51 and a horizontally extending mounting rod body 52 connected to the lower end of the main rod body 51. The end of the mounting rod body 52 away from the main rod body 51 faces away from the floating rod 7, and this end is connected to a connecting block 53. The purpose of designing the fixing rod 5 as an L-shape is to allow the adjustment slot 41 to be outside the position adjustment range of the main rod body 51, thereby separating the adjustment slot 41 from the placement space of the object being measured, so as to avoid the adjustment slot 41 affecting the stability of the object being measured placed above the measuring platform 4.

[0039] The column 6 is fixed to the measuring platform 4 by bolts or welding. The column 6 remains fixed during the actual measurement process or the adjustment of the instrument.

[0040] The floating rod 7 is mounted on one side of the column 6 via a rod holder 9. Specifically, the rod holder 9 has an overall L-shaped structure, with one end facing the column 6 and the other end facing the fixed rod 5. The end of the rod holder 9 facing the column 6 is fixed to the column 6 by a clamp. The floating rod 7 is hinged to the side of the rod holder 9 facing the fixed rod 5 via a hinge shaft, and the axis of the hinge shaft extends horizontally, while its extension direction is perpendicular to the arrangement direction of the floating rod 7 and the fixed rod 5. A high-precision bearing is installed between the floating rod 7 and the hinge shaft to ensure the stability of the floating rod 7 during rotation and reduce errors caused by the positional deviation of the floating rod 7 itself.

[0041] The floating rod 7 is hinged to the rod holder 9 in the middle. The floating rod 7 is divided into an upper part and a lower part by the hinge shaft. The lower part of the floating rod 7 is the contact part used to contact the object being measured, and the upper part of the floating rod 7 is used to contact the measuring instrument 8 to monitor the floating amount of the floating rod 7. The lower part of the floating rod 7 has a protrusion 71 that protrudes towards the fixed rod 5. The side of the floating rod 7 that is used to contact the object being measured is the side of the protrusion 71 facing the fixed rod 5.

[0042] The measuring gauge 8 is mounted on one side of the column 6 via a gauge holder 10. The gauge holder 10 is located above the rod 9 and has a flat structure. One end of the gauge holder 10 is fixed to the column 6 with a clamp, and the measuring gauge 8 is fixedly mounted on the other end of the gauge holder 10. The extendable detection end of the measuring gauge 8 abuts against the side of the upper half of the floating rod 7 facing away from the fixed rod 5. When the lower half of the floating rod 7 swings, its upper half swings in the opposite direction. The measuring gauge 8 can measure the swing amplitude of its upper half, and then calculate the swing amplitude of the lower half's measurement position through geometric calculation. This setting allows the measuring gauge 8 to be positioned high, making it convenient for the operator to observe the readings. The measuring gauge 8 can be a mechanical dial indicator or a digital dial indicator.

[0043] The fixed rod 5 has a cylindrical surface on the side facing the floating rod 7, and the lower half of the floating rod 7 has a cylindrical surface on the side facing the fixed rod 5. In the actual measurement process, the axes of the cylindrical surfaces on the fixed rod 5 and the floating rod 7 are kept vertical.

[0044] The floating rod 7 is equipped with an elastic element that allows it to press against the object being measured during actual measurement. In this embodiment, the elastic element is specifically a torsion spring located at the hinge point between the floating rod 7 and the rod frame 9. The torsion spring is well-concealed and unlikely to affect the operation. In other embodiments, the elastic element can also be a tension spring located between the upper half of the floating rod 7 and the column 6. When no measurement operation is being performed, the lower half of the floating rod 7 is tilted towards the fixed rod 5 under the action of the elastic element. Before the measurement operation is performed, the cylindrical axes of both the floating rod 7 and the fixed rod 5 need to be vertical, and the distance between the cylindrical surfaces of the floating rod 7 and the fixed rod 5 needs to match the size of the object being measured.

[0045] In addition, the floating rod 7 is also equipped with an auxiliary tool for adjusting it to a vertical state. This auxiliary tool can be a bubble level, a digital inclinometer, or a laser fixedly installed on the floating rod 7. The laser shines downwards, and when a mark is set on the measuring platform 4 and the laser shines on the mark, the floating rod 7 is in a vertical state.

[0046] In other embodiments, the fixed rod 5 can be kept fixed relative to the measuring platform 4, while the column 6 is equipped with an adjustment structure so that the position of the column 6 can be adjusted when needed, thereby realizing the adjustment of the distance between the floating rod 7 and the fixed rod 5.

[0047] In other embodiments, the measuring gauge 8 can also be installed below the rod holder 9 so that the measuring gauge 8 can directly measure the amount of floating of the floating rod 7 below the rotation center axis.

[0048] Specific Embodiment 1 of the method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing provided by the present invention: This measurement method utilizes the aforementioned self-aligning roller bearing inner ring raceway diagonal measuring instrument for measurement operations. Specifically, it includes the process of adjusting the instrument using standard part 2 and the actual measurement process. In this embodiment, standard part 2 is a standard sample ring selected from the bearing inner ring. This standard sample ring is calibrated by metrology personnel before use to obtain its diagonal dimensions. The diagonal dimensions of the standard sample ring need to be within the design range of this dimension to facilitate calculation and reduce measurement errors.

[0049] Combined with appendix Figure 2 and attached Figure 3 The process of adjusting the instrument is as follows: (1) Adjust the floating rod 7 to a vertical position (the axis of the cylindrical surface is vertical); (2) Move the fixed rod 5 and the standard part 2 so that the bottom of the grooves of the two raceways 101 of the standard part 2 comes into contact with the floating rod 7 and the fixed rod 5, which are already in a vertical state; (3) Lock the fixing rod 5; (4) Measure the diagonal dimensions of standard part 2 and zero the measuring table 8.

[0050] Adjusting the floating rod 7 to a vertical position can be done using the auxiliary tool provided on it. This vertical adjustment facilitates operation and reduces measurement errors. During the swinging motion of the floating rod 7, the measuring end of the measuring instrument 8 slides relative to the surface of the floating rod 7. With the same swing amplitude, the closer the floating rod 7 and the measuring instrument 8 are initially perpendicular, the smaller the sliding distance of the measuring end of the measuring instrument 8 on the surface of the floating rod 7, thus reducing measurement errors.

[0051] After the floating rod 7 is in a vertical position, adjust the preload of the measuring gauge 8 so that the preload of the measuring gauge 8 is greater than half the difference between the minimum and maximum limit dimensions of the diagonal of the raceway 101 of the inner ring 1 being measured, while being less than or equal to half the range of the measuring gauge 8. Adjusting the preload ensures that the measuring gauge 8 has a certain measurement range both vertically and horizontally, facilitating measurement operations. In other embodiments, the preload of the measuring gauge 8 can be directly adjusted to half its range.

[0052] During the subsequent adjustment of the position of the fixed rod 5, one person can hold the already vertical floating rod 7 while another person adjusts the position of the fixed rod 5. During the adjustment of the fixed rod 5, the standard part 2 is only used as a reference to determine the approximate distance between the fixed rod 5 and the floating rod 7. After the position of the fixed rod 5 is determined and it is locked, the floating rod 7 can be released, allowing it to naturally rest against the standard part 2 due to the force provided by the elastic element. Alternatively, one person can hold the fixed rod 5 and the standard part 2, with the standard part 2 in contact with the fixed rod 5, while the floating rod 7 rests against the standard part 2 under the action of the elastic element. Then, the fixed rod 5 and the standard part 2 are moved to make the floating rod 7 vertical, after which another person locks the fixed rod 5.

[0053] During the above process, the cylindrical surfaces of the two rods (fixed rod 5 and floating rod 7) abut against the bottom of the grooves of the two raceways 101 of the standard part 2 to form point contact. However, the line connecting the contact points may not coincide with the diagonal of the standard part 2 and may have a certain skew angle. Therefore, the diagonal dimension of the raceway 101 of the standard part 2 cannot be accurately obtained during the above process, or in other words, the diagonal dimension of the hob of the standard part 2 cannot be matched with the specific reading on the measuring table 8.

[0054] To achieve more accurate measurement of the diagonal dimension of the hob cutter in standard part 2, it is necessary to align one of the diagonals of the hob cutter in standard part 2 with the line connecting the two contact points. At this point, the distance between the two contact points is minimized and can represent the diagonal dimension of standard part 2. The specific operation involves placing standard part 2 on the upper surface of measuring table 4, keeping the axis of standard part 2 perpendicular to the cylindrical axis of the two rods, and continuously swinging standard part 2 until the line connecting the contact points coincides with the diagonal at a certain moment. During this process, the measuring gauge 8 is continuously observed; the line connecting the contact points coincides with the diagonal when the reading on measuring gauge 8 is at its minimum.

[0055] Next, zero the measuring gauge 8. When the reading of measuring gauge 8 is at its minimum, it represents the diagonal dimension of the corresponding standard part 2. Since the other inner rings 1 being measured need to be calculated based on this dimension, adjusting the zero point of measuring gauge 8 to its minimum reading facilitates measurement and calculation. Before zeroing measuring gauge 8, the preload can be adjusted again using the same method as described above.

[0056] Still combined with appendix Figure 2 and attached Figure 3 The actual measurement process is as follows: (1) Place the inner ring 1 to be measured between the two rods and make the two raceways 101 of the inner ring 1 to be measured press against the cylindrical surfaces of the two rods to form point contact; (2) Keep the axis of the inner ring 1 being measured perpendicular to the cylindrical axis of the two rods and swing the inner ring 1 being measured so that the line connecting the contact points coincides with the diagonal at a certain moment. When the line connecting the contact points coincides with the diagonal, the distance between the two contact points is the smallest and can represent the diagonal dimension. During this process, observe the measuring table 8 at all times and record the minimum value of the reading of the measuring table 8. This minimum value is the measured value when the line connecting the contact points coincides with the diagonal.

[0057] (3) Through geometric calculation, the measured value is converted into the floating amount of the contact position between the floating rod 7 and the inner ring 1 being measured, which is the deviation of the diagonal dimension of the raceway 101 of the inner ring 1 being measured from the diagonal dimension of the standard part 2. Finally, the deviation is combined with the diagonal dimension of the standard part 2 to obtain the measured value of the diagonal dimension of the raceway 101 of the inner ring 1 being measured.

[0058] Regarding geometric calculations, the distance from the contact point between the measuring gauge 8 and the floating rod 7 to the rotation center of the floating rod 7 can be taken as h1, and the distance from the contact point between the inner ring 1 being measured and the floating rod 7 to the rotation center of the floating rod 7 can be taken as h2. The change in the measured value of the measuring gauge 8 is Δ1. Then, the deviation of the diagonal dimension of the raceway 101 of the inner ring 1 being measured compared to the diagonal dimension of the standard part 2 is Δ2 = Δ1(h2 / h1). Then, based on the direction of the deviation, the diagonal dimension of the standard part 2 is added to or subtracted from this dimensional deviation Δ2 to obtain the measured value of the diagonal of the inner ring 1 being measured.

[0059] Finally, the measured value of the diagonal dimension of the inner ring 1 raceway 101 is compared with the minimum and maximum limit dimensions of the diagonal design to determine whether the diagonal dimension of the inner ring 1 raceway 101 is qualified.

[0060] In other embodiments, the floating rod 7 can be adjusted to a vertical position without the aid of auxiliary tools. Since the deviation of the diagonal dimension of the raceway 101 of the inner ring 1 being measured is very small, the floating angle of the floating rod 7 caused by this deviation is also very small. Therefore, it is not necessary to maintain a strict perpendicular relationship between the floating rod 7 and the measuring instrument 8. As long as the initial tilt angle of the floating rod 7 is not very large, the resulting error is within an acceptable range. Therefore, it is also acceptable for the operator to adjust the floating rod 7 to be vertical by visual observation, which meets the measurement requirements.

[0061] In other embodiments, the measurement operation can be performed without directly using the self-aligning roller bearing inner ring raceway diagonal measuring instrument provided in the above embodiments. Instead, other instruments with the same design concept as the self-aligning roller bearing inner ring raceway diagonal measuring instrument provided in the above embodiments can be used. For example, the floating rod 7 can slide and translate along its floating direction instead of having to rotate. Therefore, this method for measuring the diagonal of the self-aligning roller bearing inner ring raceway does not necessarily rely on the aforementioned self-aligning roller bearing inner ring raceway diagonal measuring instrument. The instrument used in this method only needs two rods with cylindrical surfaces and parallel cylindrical axis axes, which can serve as the fixed rod 5 and the floating rod 7 that can float along their arrangement directions, respectively.

[0062] Specific Embodiment 2 of the method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing provided by the present invention: This embodiment is based on Embodiment 1, and the difference from Embodiment 1 is as follows (see Appendix). Figure 5 and attached Figure 6 In this embodiment, the standard part 2 is an object with a cylindrical outline, such as a solid cylinder or a hollow tube, so that the outer diameter of the standard part 2 matches the design value of the diagonal dimension of the inner ring 1 being measured.

[0063] Specifically, the outer diameter of the standard part 2 needs to be located between the minimum and maximum limit dimensions of the diagonal of the inner ring 1 being measured. This ensures that the deviation between the diagonal dimension of the inner ring 1 and the outer diameter of the standard part 2 is within the deviation range of the diagonal dimension, thus reducing error. In other embodiments, the outer diameter of the standard part 2 can also be located outside the minimum and maximum limit dimensions of the diagonal of the inner ring 1 being measured, but the difference between the outer diameter of the standard part 2 and the limit dimension of the diagonal of the inner ring 1 being measured should not be too large.

[0064] During the instrument adjustment process, standard part 2 is placed between the two rods and the outer circumference of standard part 2 is pressed against the cylindrical surfaces of the two rods to form point contact. The axis of standard part 2 is kept perpendicular to the axis of the cylindrical surfaces of the two rods and the standard part 2 is swung so that the line connecting the contact points can coincide with the diameter of standard part 2 at a certain moment. When the line connecting the contact points coincides with the diameter, the distance between the two contact points is the smallest and can represent the diameter of standard part 2.

[0065] The diagonal dimension of the standard sample ring selected from the machined bearing inner ring is difficult to verify, and the obtained standard dimension is not accurate enough. Therefore, the diagonal dimension of the inner ring 1 obtained by using it as a reference will inevitably have a large error. In contrast, the standard part 2, with its cylindrical outline, has a simpler structure, making it easier to verify its diameter and obtain accurate dimensional data. Therefore, the error in the diagonal dimension of the inner ring 1 obtained by using it as a reference will be smaller.

[0066] In this embodiment, during the instrument adjustment process, the standard part 2 is placed directly on the measuring platform 4, and the height of the contact point between the standard part 2 and the floating rod 7 is equal to the radius of the standard part 2. The inner ring 1 to be measured is also placed directly on the measuring platform 4, and the height of the contact point between the inner ring 1 and the floating rod 7 is equal to the radius of its central flange 102. The radius of the central flange 102 of the inner ring 1 to be measured is greater than half of its diagonal, so the actual height of the contact point between the inner ring 1 and the floating rod 7 is higher than the height of the contact point between the standard part 2 and the floating rod 7.

[0067] In this case, it is necessary to strictly control the initial verticality of the floating rod 7 to reduce measurement errors. When the contact positions of the inner ring 1 and the floating rod 7, as well as the contact positions of the standard part 2 and the floating rod 7, are both far from the rotation center of the floating rod 7, the detection error will be very small if the floating rod 7 is initially kept in good verticality. To further reduce the error, the distances between the contact positions of the inner ring 1 and the floating rod 7, and the contact positions of the standard part 2 and the floating rod 7, and the rotation center of the floating rod 7 can be measured separately, and then converted accordingly.

[0068] Specific embodiment 3 of the method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing provided by the present invention: This embodiment is based on Embodiment 2, and the difference between it and Embodiment 2 is as follows (see Appendix). Figure 7 In this embodiment, a standard pad 3 is configured for standard part 2.

[0069] In this embodiment, during the instrument adjustment process, a standard pad 3 is first placed on the measuring platform 4, and then the axis of the standard part 2 is placed horizontally on the standard pad 3 so that its outer circumferential surface contacts the upper surface of the standard pad 3. The height of the standard pad 3 is equal to half of the outer diameter of the middle flange 102 of the inner ring 1 minus the diagonal in the design dimensions of the inner ring 1 being measured.

[0070] In the actual measurement process, the axis of the inner ring 1 to be measured is placed horizontally on the standard pad 3 and the outer peripheral surface of the inner ring 1 is in contact with the upper surface of the standard pad 3. This makes the height of the contact position between the inner ring 1 to be measured and the floating rod 7 equal to the height of the contact position between the standard part 2 and the floating rod 7. The contact positions are approximately the same, which can greatly reduce the influence of the initial tilt angle of the floating rod 7 on the measurement error.

[0071] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still make modifications to the technical solutions described in the foregoing embodiments without creative effort, or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing, characterized in that, The instrument implementing this method comprises two rods with their cylindrical axes parallel. The two rods are respectively designated as a fixed rod and a floating rod capable of gliding along their alignment. Before actual measurement, the instrument is adjusted using a standard component to ensure the initial distance between the floating rod and the fixed rod equals the corresponding dimension of the standard component. During adjustment, the standard component is placed between the two rods and brought into point contact with the cylindrical surfaces of both rods. The axis of the standard component is kept perpendicular to the cylindrical axes of the two rods, and the standard component is swung to minimize the distance between the two contact points at a given moment. The distance is used to represent the corresponding dimension. In actual measurement, the inner ring to be measured is placed between the two rods and the two raceways of the inner ring to be measured are pressed against the cylindrical surfaces of the two rods to form point contact. The axis of the inner ring to be measured is kept perpendicular to the axis of the cylindrical surfaces of the two rods and the inner ring to be measured is swung so that the line connecting the contact points can coincide with the diagonal at a certain moment. When the line connecting the contact points coincides with the diagonal, the distance between the two contact points is the smallest and can represent the diagonal dimension. The deviation between the inner ring to be measured and the corresponding dimension of the standard part is obtained by reading the floating amount of the floating rod, and then the diagonal dimension value of the inner ring to be measured is calculated.

2. The method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing according to claim 1, characterized in that, A cylindrical object is selected as the standard part, and the outer diameter of the standard part is matched with the design value of the diagonal dimension of the inner raceway to be measured. During the instrument adjustment process, the standard part is placed between the two rods and the outer circumferential surface of the standard part is pressed against the cylindrical surface of the two rods to form point contact.

3. The method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing according to claim 2, characterized in that, The outer diameter of the standard part lies between the minimum and maximum limit dimensions of the diagonal of the inner ring being measured.

4. The method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing according to claim 2 or 3, characterized in that, The instrument has a measuring platform. Before measurement, the upper surface of the measuring platform is adjusted to be horizontal. At this time, the cylindrical axes of the fixed rod and the floating rod are vertical. During the instrument adjustment process, a standard pad is first placed on the measuring platform. Then, the axis of the standard part is placed horizontally on the standard pad and its outer circumference is in contact with the upper surface of the standard pad. The height of the standard pad is equal to half of the outer diameter of the middle flange of the inner ring to be measured minus the diagonal. In the actual measurement process, the axis of the inner ring to be measured is placed horizontally on the standard pad and its outer circumference is in contact with the upper surface of the standard pad.

5. The method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing according to claim 2 or 3, characterized in that, During the instrument adjustment process, first adjust the floating rod to a vertical position, then move the fixed rod and the standard part so that the standard part is in contact with the floating rod, which is already in a vertical position, and also in contact with the fixed rod. At this time, lock the fixed rod, and then measure the outer diameter of the standard part.

6. The method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing according to claim 5, characterized in that, When the floating rod is in a vertical position, the preload of the measuring gauge is greater than half of the difference between the minimum and maximum limit dimensions of the inner raceway diagonal, while being less than or equal to half of the measuring gauge's range.

7. The method for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing according to claim 1, characterized in that, The standard part is a standard sample ring selected from the inner ring of the bearing. The diagonal dimension of the standard sample ring is within the design range of the diagonal dimension of the inner ring being measured. During the instrument adjustment process, the standard part is placed between the two rods and the two raceways of the standard part are pressed against the cylindrical surfaces of the two rods to form point contact.

8. An instrument for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing, characterized in that, The device includes a measuring platform for placing a standard part or the inner ring to be measured. A fixed rod and a column are mounted above the measuring platform. A floating rod is hinged to the column. The rotation center axis of the floating rod is horizontal and perpendicular to the arrangement direction of the floating rod and the fixed rod. Both the floating rod and the fixed rod have vertically oriented cylindrical surfaces on their opposing sides for point contact with the object being measured. One of the fixed rod and the column is equipped with an adjustment structure to adjust the distance between the fixed rod and the floating rod. The floating rod is equipped with an elastic element to press it against the object being measured. A measuring gauge is also mounted on the column. The measuring gauge's detection end contacts the side of the floating rod away from the fixed rod to detect the floating rod's float. The adjustment structure includes an adjustment slot on the measuring platform, extending parallel to the arrangement direction of the fixed rod and the floating rod. The lower end of the fixed rod is fixed in the adjustment slot by fasteners to make its position adjustable. The portion of the floating rod below the rotation center axis is the contact portion for contacting the standard part or the inner ring to be measured.

9. The self-aligning roller bearing inner ring raceway diagonal measuring instrument according to claim 8, characterized in that, The fixed rod includes a vertically extending main rod body and a horizontally extending mounting rod body connected to the lower end of the main rod body. The end of the mounting rod body away from the main rod body faces away from the floating rod, and this end is connected to a guide connecting block installed in the adjustment slot, so that the adjustment slot can be outside the position adjustment range of the main rod body.

10. The instrument for measuring the diagonal of the inner ring raceway of a self-aligning roller bearing according to claim 8 or 9, characterized in that, The measuring end of the measuring instrument contacts the part of the floating rod located above the center axis of rotation.

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