JP3804233B2 - Ball bearing inspection method and inspection apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention measures a physical quantity such as vibration and sound pressure generated from a ball bearing to be inspected with relative rotation of an inner ring and an outer ring of the ball bearing to be inspected, and inspects the ball bearing based on the result of the measurement. Bearing inspection methodAnd inspection equipmentAbout.
[0002]
[Prior art]
In general, a ball bearing has a groove formed on an outer peripheral surface and is fixed to a shaft of a rotating machine part, an outer ring formed with a groove on an inner peripheral surface and fixed to a bearing portion, and a groove and an outer ring of the inner ring. A spherical rolling element made of a plurality of steel balls, ceramics, or the like incorporated between the grooves is formed as a main component.
[0003]
The inspection method will be described by taking as an example a ball bearing in which a steel ball is incorporated as the rolling element.
[0004]
When this ball bearing is assembled, the ball bearing alone is passed to an inspection process for comprehensively judging the quality of the ball bearing. In this inspection process, the inner ring of the ball bearing to be inspected is attached to a reference rotating shaft that rotates about its axis, and the reference rotating shaft is rotated while preloading the outer ring of the ball bearing to be inspected in the axial direction. Thus, the inner ring is rotated relative to the outer ring, and physical quantities such as vibration and sound pressure generated from the ball bearing to be inspected with relative rotation between the inner ring and the outer ring are measured. Inspection is performed by a method for determining the quality of the ball bearing to be inspected based on the result.
[0005]
Next, the above-described inspection method and the ball bearing inspection device for carrying out the method will be specifically described with reference to FIGS. FIG. 4 is a block diagram showing the main part of a conventional ball bearing inspection device, and FIG. 5 is a diagram schematically showing the state of rotation and revolution of the ball of the ball bearing inspected by the inspection device of FIG. It is.
[0006]
As shown in FIG. 4, the conventional ball bearing inspection apparatus includes a base 50. The base 50 includes a bearing rotating means for rotating the inner ring 4 b of the ball bearing 4 to be tested, and the ball bearing 4 to be tested. Preload applying means for applying a preload to the outer ring 4a is mounted.
[0007]
The bearing rotating means has a spindle 30, and the spindle 30 is provided with a spindle rotating shaft 1 that forms a reference rotating shaft. The spindle rotating shaft 1 is supported by a plurality of radial bearings 31 and a plurality of thrust bearings 32, and each radial bearing 31 and each thrust bearing 32 is formed of an air hydrostatic bearing. One end of the spindle rotating shaft 1 is configured so that an inner ring 4b of the ball bearing 4 to be inspected can be attached. A pulley 36 is attached to the other end of the spindle rotating shaft 1. The spindle rotating shaft 1 is rotated by the driving force of the rotation driving motor 34, and the driving force of the rotation driving motor 34 is stretched over a pulley 38 attached to the output shaft of the motor, and the pulley 38 and the pulley 36. It is transmitted to the spindle rotating shaft 1 by the belt 37.
[0008]
The preload applying means has a preload slider 23 that can move on the bed 50 along the axial direction of the spindle rotation shaft 1, and a nut 24 a is fixed to the preload slider 23. A male screw 25 is screwed onto the nut 24a, and the male screw 25 is supported by a male screw support portion 26 so as to be rotatable about its axis. The male screw 25 is rotated by a preload drive motor 27, and the preload slider 23 is moved along the axial direction of the spindle rotating shaft 1 as the male screw 25 rotates. One end of a preload spring 6 as an elastic member is fixed to the surface of the preload slider 23 facing the spindle rotation shaft 1, and a preload ring 22 is attached to the other end of the preload spring 6. As the elastic member, in addition to the preload spring 6 shown in FIG. 4, an annular hard rubber is used, and both ends thereof are fixed to the preload slider 23 and the preload ring 22, or a plurality of springs are used as the preload slider 23 and the preload ring 22. It is good also as a structure etc. hold | maintained between opposing surfaces. The preload ring 22 is abutted against the outer ring 4 a of the ball bearing 4 to be tested while resisting the spring force of the preload spring 6 by the movement of the preload slider 23, and the preload applied to the outer ring 4 a of the ball bearing 4 to be tested is the preload slider 23. Is determined in accordance with the moving position of each and the spring constant of each preload spring 6.
[0009]
For measurement of vibration generated from the ball bearing 4 during rotation of the ball bearing 4 to be inspected, that is, while the inner ring 4b is rotating relative to the outer ring 4a, a converter 40 or the like that is in direct contact with the outer ring 4a. A vibration measuring device is used, and the vibration is converted into an electric signal by the converter 40, and this electric signal is input to a measuring device main body (not shown). The relative positioning of the converter 40 and the outer ring 4 a is performed by adjusting the position of the converter 40 by the converter position adjustment slider 41. When measuring the sound pressure generated from the ball bearing 4 to be inspected, a sound pressure measuring device comprising a microphone 42 or the like held at a predetermined interval from the ball bearing 4 to be inspected is used.
[0010]
Next, an inspection procedure using the above-described inspection apparatus will be described.
[0011]
First, the inner ring 4 b of the ball bearing 4 to be inspected is attached to one end of the spindle rotating shaft 1. Next, the preload slider 23 is moved to a predetermined position and the preload ring 22 is brought into contact with the outer ring 4a of the ball bearing 4 to be inspected, whereby a predetermined preload is applied to the outer ring 4a in the axial direction.
[0012]
Next, when a predetermined preload is applied to the outer ring 4a, the spindle rotating shaft 1 is rotated by the rotation drive motor 34, and the inner ring 4b rotates relative to the outer ring 4a. As shown in FIG. 5, each steel ball 3 held between the groove of the inner ring 4b and the groove of the outer ring 4a is rotated by the preload applied to the outer ring 4a. While rotating at a point Ao, Ai so as to form a contact angle α with respect to the groove, the axis B perpendicular to the straight line connecting the contact points Ao, Ai is rotated as a rotation axis and revolved around the axis of the spindle rotation axis 1 To do.
[0013]
The vibration or sound pressure generated from the ball bearing 4 to be inspected in this rotating state is measured, and the quality of the ball bearing 4 to be inspected is determined based on the measurement result.
[0014]
[Problems to be solved by the invention]
However, in the above-described conventional inspection method, each steel ball 3 is in contact with the grooves of the inner ring 4b and 4a by the preload applied to the outer ring 4a while contacting at the points Ao and Ai so as to form the contact angle α. Since B rotates with B as the rotation axis, the contact area of each of the steel balls 3 with respect to the grooves of the outer rings 4b and 4a is specified as a minute width area sandwiching a great circle corresponding to the equator with the axis B as the north and south poles, Only a measurement result for a surface area of several percent of the total surface area of each steel ball 3 is obtained. Therefore, the finishing accuracy of the steel balls 3 and the presence or absence of scratches on the surface cannot be inspected over the entire surface area of the steel balls 3, and the inspection with high inspection accuracy to obtain sufficient quality assurance for the ball bearing 4 to be inspected. It is difficult to carry out.
[0015]
  In order to solve the above-described problems, the present invention provides a ball bearing inspection method capable of significantly improving the inspection accuracy for obtaining sufficient quality assurance for the ball bearing to be inspected.And inspection equipmentThe purpose is to provide.
[0016]
[Means for Solving the Problems]
  According to the present invention, an inner ring of a ball bearing to be inspected is attached to a reference rotating shaft that rotates about its axis, and the reference rotating shaft is rotated while preloading the outer ring of the ball bearing to be inspected in the axial direction. The inner ring is rotated relative to the outer ring, and physical quantities such as vibration and sound pressure generated from the ball bearing to be inspected with relative rotation between the inner ring and the outer ring are measured. In the ball bearing inspecting method for inspecting the ball bearing based on the above, each of the ball bearings held between the groove of the inner ring and the groove of the outer ringRolling elementThe abutting portion formed on the rotating body rotating coaxially with the reference rotation shaft, and rotating the reference rotation shaft while applying the preload to the outer ring,Rolling elementRotating the rotating body while variably controlling the rotation speed of the rotating body so that theRolling elementMeasuring the physical quantity generated from the ball bearing to be inspected in a state of being skewed.Provide inspection methods for ball bearings.
  In the inspection method, it is preferable to control the rotational speed of the rotating body to change periodically.
  The present invention also provides a reference rotating shaft to which the inner ring of a ball bearing to be inspected comprising an inner ring and an outer ring, and a plurality of spherical rolling elements interposed between the inner ring and the outer ring, and the inner ring by rotating the reference rotating shaft. And a preload ring for applying a preload to the outer ring of the ball bearing to be inspected. Provided is a ball bearing inspection device comprising skew drive means having a rotating body that is abutting portion that is abutted against a plurality of rolling elements.
  In the inspection apparatus, the skew driving unit controls the skew driving motor to rotate the rotating body coaxially with the reference rotation shaft, and controls the rotation speed of the rotating body by the skew driving motor to periodically change. It is preferable to provide a motor controller.
[0017]
  In the ball bearing inspection method of the present invention, each of the holdings between the groove of the inner ring and the groove of the outer ringRolling elementThe abutting part formed on the rotating body that rotates coaxially with the reference rotation shaft is abutted, and the reference rotation shaft is rotated while preloading the outer ring.Rolling elementThe rotating body is rotated while the rotational speed of the rotating body is variably controlled so that a skew motion is caused by the abutting portion. In this case, eachRolling elementThe autorotation motion is a combination of the autorotation component due to the rotation of the reference rotation shaft and the autorotation component due to the rotation of the rotating body transmitted through the abutment portion of the rotating body. Here, the rotation component due to the rotation of the rotating body means that one point on the rotation center axis is perpendicular to the rotation center axis of the reference rotation axis.Rolling elementThis is a rotation component having an axis passing through the center of the axis as the rotation axis. Therefore, the rotational speed of the rotating body varies by variably controlling the rotational speed of the rotating body.Rolling elementThe rotation axis of the rotation movement of this will fluctuate. That is, eachRolling elementWill skew.
[0018]
  Thus, eachRolling elementThe abutment part of the rotating body is abutted to each other and the rotating body is rotated in a direct manner.Rolling elementEach of which is given a skew motion.Rolling elementA skew motion can be reliably applied to all of the above. Also, eachRolling elementBy simultaneously abutting the abutting part of the rotating body on eachRolling elementIt is possible to reliably and simultaneously apply skew motion to all of the above.
[0019]
  thisRolling elementDue to the skew movement ofRolling elementThe locus of contact points between the inner ring and outer ringRolling elementCan be gradually shifted on the surface,Rolling elementThe trajectory of the contact point between the inner ring and the outer ring is not limited to a very small area as in the prior art,Rolling elementOn the surfaceRolling elementThe point of contact with the inner ring and the outer ring extends over an extremely wide area in a short time.
[0020]
  Therefore, eachRolling elementBecause the physical quantity generated from the ball bearing to be inspected is measured while the head is skewing,Rolling elementIncludes measurement results of contact state with inner and outer grooves in almost all areas of the surface,Rolling elementFinish accuracy, surface scratchesRolling elementCan be inspected over the entire surface area.
[0021]
  In particular, the rotational speed applied to the rotating body is periodically varied, for example, by changing it to a sinusoidal shape, and the period is given by the rotation of the reference rotation shaft.Rolling elementBy slightly larger or smaller than the rotation period of each rotation,Rolling elementAmong them, a locus is drawn in which the contact points with the outer ring are regularly shifted little by little. Therefore,Rolling elementSince the measurement is performed in such a skew motion state,Rolling elementThe entire surface can be brought into contact with the inner and outer rings evenly and uniformly, and a more reliable test result can be obtained in a short time.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0023]
(First embodiment)
FIG. 1 is a block diagram showing the main part of an inspection apparatus used in a first embodiment of the ball bearing inspection method of the present invention.
[0024]
As shown in FIG. 1, the ball bearing inspection device includes a bearing rotating means for rotating the inner ring 4 b of the ball bearing 4 to be tested, and a preload applying means for applying a preload to the outer ring 4 a of the ball bearing 4 to be tested. And skew drive means for causing the steel balls 3 incorporated between the grooves of the inner and outer rings 4b and 4a to perform a skew motion, the bearing rotating means, the preload applying means and the skew drive means are beds (see FIG. (Not shown). In the present embodiment, an inspection ball bearing 4 in which a steel ball 3 is held by a cage 2 will be described as an example of the ball bearing to be inspected.
[0025]
The bearing rotating means has the same configuration as the bearing rotating means of the inspection apparatus shown in FIG. 4, and the spindle rotating shaft 1 is rotated by the driving force transmitted from the rotation driving motor through the pulleys and belts. 1 is attached with an inner ring 4b of the ball bearing 4 to be inspected.
[0026]
The preload applying means has a preload slider 8 that can move on the bed along the axial direction of the spindle rotation shaft 1, and the preload slider 8 is rotated by a preload drive motor with a male screw screwed into a nut fixed thereto. As a result, it is moved along the axial direction of the spindle rotation shaft 1. One end of a preload spring 6 as an elastic member is fixed to a surface of the preload slider 8 facing the spindle rotation shaft 1, and a preload ring 5 is attached to the other end of the preload spring 6. As the elastic member, in addition to the preload spring 6 shown in FIG. 3, an annular hard rubber is used, and both ends thereof are fixed to the preload slider 23 and the preload ring 22, and a plurality of springs are used as the preload slider 23 and the preload ring 22. It is good also as a structure etc. hold | maintained between opposing surfaces. The preload ring 5 is abutted against the outer ring 4a of the ball bearing 4 to be tested while resisting the spring force of the preload spring 6 by the movement of the preload slider 8, and the preload ring 5 is abutted against the outer ring 4a of the ball bearing 4 to be tested. The preload to be applied is determined according to the moving position of the preload slider 8 and the spring constant of the preload spring 6.
[0027]
  The skew drive means has a skew drive shaft 7 that extends coaxially with the spindle rotation shaft 1 and penetrates the inside of the preload slider 8. One end of the skew drive shaft 7 protrudes from the preload slider 8 toward the spindle rotation shaft 1, and an abutting portion 7 c that can abut against each steel ball 3 is formed at the one end. As a material constituting the abutting portion 7c,steelBy hitting the ball 3steelA material that does not have the risk of damaging the surface of the sphere 3 is required, and the abutting portion 7c andsteelIn order to prevent wear powder generated by contact with the ball 3 from entering the bearing, a material that does not generate this wear powder is required, and the abutting portion 7c is made of Teflon (registered trademark), nylon, or the like. It is preferable to comprise a resin material. The other end of the skew drive shaft 7 protrudes from the preload slider 8 toward the opposite side of the spindle rotation shaft 1, and a pulley 12 is attached to the other end by a lock nut 7b. A flange portion 7 a is formed in the middle of the skew drive shaft 7, and the flange portion 7 a is accommodated in a cylinder 8 b formed inside the preload slider 8. The flange portion 7a functions as a piston with respect to the cylinder 8b. The flange portion 7a cooperates with the cylinder 8b and is supplied to the cylinder 8b from an air pressure circuit (not shown) through the air passage 8c or the air passage 8d. A piston / cylinder mechanism for moving the flange portion 7a by pressurized air is configured.
[0028]
The skew drive shaft 7 is supported by an air bearing 8a (static pressure radial bearing) formed inside the preload slider 8 so as to be rotatable and reciprocally movable. The air bearing 8a includes an air inlet and a plurality of air escape grooves. The skew drive shaft 7 is rotated by the driving force from the skew drive motor 9 transmitted through the belt 11 to the pulley 12 attached to the other end of the shaft. A pulley 10 around which a belt 11 is stretched is attached to an output shaft of the skew drive motor 9. The drive control of the skew drive motor 9 is performed by the motor controller 13, and the motor controller 13 rotates the skew drive shaft 7 so that the steel ball 3 performs a skew motion by contact with the abutting portion 7c of the skew drive shaft 7. That is, drive control of the skew drive motor 9 is performed while controlling the rotation speed of the skew drive motor 9. In this rotational speed control, specifically, the skew drive motor 9 is added to a speed obtained by superimposing a constant rotational speed component (for example, a speed equal to the revolution speed of the steel ball 3) with a changing speed component that changes in a waveform indicated by a sine function. The skew drive motor 9 is driven and controlled so that the rotational speeds of the two coincide with each other. Here, the period of the change speed component is slightly larger or smaller than the rotation period of the steel ball. However, the ratio of both periods is set so as not to be an integral multiple.
[0029]
The skew drive shaft 7 is reciprocated in the axial direction by a piston / cylinder mechanism constituted by the flange portion 7a and the cylinder 8b, and the steel of the abutting portion 7c formed at one end of the skew drive shaft 7 by this reciprocation. The pressing force against the ball 3 is determined.
[0030]
Next, the configuration of the motor controller 13 will be described with reference to FIG. FIG. 2 is a block diagram showing the configuration of the motor controller of FIG.
[0031]
As shown in FIG. 2, the motor controller 13 includes a CPU 14 that generates a command related to drive control of the skew drive motor 9 at a predetermined timing in accordance with a program stored in the ROM 14 a, and drive control of the skew drive motor 9 by the CPU 14. Is started or stopped in response to an operation input from the operation unit 14b. The command generated from the CPU 14 includes a command for instructing the function generator 15 to generate a sine wave having a frequency component corresponding to the period of the change speed component. When this command is given to the function generator 15, the function generator 15 generates a sine wave signal having a frequency component corresponding to the period of the change speed component. The sine wave signal generated by the function generator 15 is input to the F / V converter 16, and the F / V converter 16 generates a DC voltage whose voltage value changes in accordance with the frequency component of the input sine wave signal. appear.
[0032]
The DC voltage generated by the F / V converter 16 is added by the adder 18 to the constant speed rotation command voltage generated by the constant speed rotation command voltage generation circuit 17. Here, the constant speed rotation command voltage is a DC voltage corresponding to the constant rotation speed component. Therefore, the voltage output from the adder 18 is a voltage obtained by adding the DC voltage corresponding to the change speed component and the DC voltage corresponding to the constant rotation speed component. The added voltage is applied to the skew drive motor 9 via the servo amplifier 19, and the skew drive motor 9 is rotationally driven at a speed obtained by superimposing the change speed component on the constant rotational speed component.
[0033]
Next, an inspection procedure using the above-described inspection apparatus in the present embodiment will be described.
[0034]
First, the inner ring 4 b of the ball bearing 4 to be inspected is attached to one end of the spindle rotating shaft 1. Next, the preload slider 8 is moved to a predetermined position, and the preload ring 5 is abutted against the outer ring 4a of the ball bearing 4 to be inspected as the preload slider 8 is moved to the predetermined position. A preload of a predetermined value is applied to the outer ring 4 a of the ball bearing 4 to be inspected by the abutment of the preload ring 5. In this state, there is a minute gap between the steel ball 3 and the tip of the abutting portion 7 c of the skew drive shaft 7.
[0035]
Next, the skew drive shaft 7 has the abutment portion 7c made of a steel ball by a piston / cylinder mechanism constituted by the flange portion 7a and the cylinder 8b so that the pressing force of the abutment portion 7c against the steel ball 3 becomes a predetermined value. It is struck against 3.
[0036]
  When the abutment of the preload ring 5 and the abutment portion 7c of the skew drive shaft 7 are completed, the spindle rotation shaft 1 is rotated by the rotation drive motor, and the inner ring 4b rotates relative to the outer ring 4a. At the same time, the skew drive motor 9 is subjected to the drive control as described above, whereby the skew rotation shaft 7 is rotated with periodic fluctuations. With these rotations, each steel ball 3 rotates around the axis C in FIG. 1, that is, perpendicular to the rotation center axis of the spindle rotation shaft 1 and rotates around the axis B by the preload applied to the outer ring 4 a as the rotation axis. A component whose rotational speed changes is superimposed around an axis passing through one point on the central axis and the center of each steel ball 3, and each component determined by the synthesis of both componentssteelThe rotation axis of the sphere 3 changes periodically and makes a skew motion. By applying this skew motion, each time the steel ball 3 rotates once, the trajectory of the contact point of the steel ball 3 with the outer ring 4 a and the inner ring 4 b is slightly shifted on the steel ball 3. Of these, the contact area with respect to each groove of the outer rings 4b, 4a is substantially the entire area of the steel ball surface. The degree of deviation of the trajectory is determined as appropriate because it is determined by the difference between the steel ball rotation period and the change component.
[0037]
Next, a physical quantity such as vibration or sound pressure generated from the ball bearing 4 to be inspected in a state where each steel ball 3 revolves with a skew motion is measured. The vibration generated from the ball bearing 4 to be inspected is measured by a vibration measuring device comprising a converter or the like that is in direct contact with the outer ring 4a, and the sound pressure generated from the ball bearing 4 to be inspected is held at a predetermined position. A sound pressure measuring device composed of a microphone or the like is used. The quality of the ball bearing 4 to be inspected is determined based on the measurement result.
[0038]
Thus, since the contact area with respect to each groove | channel of the outer ring | wheels 4b and 4a becomes the substantially whole area | region of the steel ball surface among the steel balls 3, the above-mentioned measurement result shows the inner and outer rings in almost the whole area of the steel ball 3 surface. The measurement result of the contact state with each groove | channel of 4b, 4a is included, and it can test | inspect in consideration of the finishing precision, the presence or absence of a crack of the surface over the whole surface area of the steel ball 3. FIG. Therefore, the inspection accuracy for obtaining sufficient quality assurance for the ball bearing 4 to be inspected can be remarkably improved.
[0039]
(Second embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a block diagram showing a main part of an inspection apparatus used in the second embodiment of the ball bearing inspection method of the present invention.
[0040]
The ball bearing inspection apparatus according to the present embodiment differs from the first embodiment in that a skew driving ring for causing the steel ball to skew is configured to abut against the steel ball from the spindle rotation shaft side.
[0041]
As shown in FIG. 3, the ball bearing inspection apparatus according to the present embodiment includes skew drive means for causing the steel balls 3 incorporated between the grooves of the inner and outer rings 4b and 4a to perform a skew motion. The skew drive means includes a skew drive ring 21 that is arranged coaxially with the spindle rotation shaft 1 and supported by a spindle 20 that supports the spindle rotation shaft 1. The skew drive ring 21 is configured such that the tip can be brought into contact with each steel ball 3, and includes a small diameter portion that receives one end of the spindle rotation shaft 1 and a large diameter portion that receives the spindle 20. A large-diameter portion of the skew drive ring 21 is supported by an air bearing 20a formed on the outer peripheral portion of the spindle 20 so as to be rotatable and reciprocally movable. The air bearing 20a includes an air inlet and a plurality of air escape grooves. . A pulley 21a is integrally formed on the outer peripheral portion of the large-diameter portion of the skew drive ring 21, and a driving force for rotating around the spindle rotation shaft 1 via the belt 11 is not shown in the pulley 21a. It is transmitted from the skew drive motor. On the inner wall of the large-diameter portion of the skew drive ring 21, a projecting portion for forming a space for receiving the end portion of the spindle 20 in cooperation with the inner wall is formed, and the spindle received in the formed space A cylinder chamber 24 to which pressurized air is supplied is defined between the end portion 20 and the inner wall of the large diameter portion of the skew drive ring 21. The cylinder chamber 24 cooperates with the skew drive ring 21 to constitute a piston / cylinder mechanism, and the skew drive ring 21 reciprocates along the axis of the spindle rotating shaft 1 by controlling the supply of the pressurized air. Functions as a piston.
[0042]
The rotational speed of the skew driving ring 21, that is, the rotational speed of the skew driving motor that generates the driving force of the skew driving ring 21, is a wave shape indicated by a sine function in a constant rotational speed component, as in the first embodiment. It is controlled so as to coincide with the speed obtained by superimposing the change speed component that changes to.
[0043]
Next, an inspection method using the above-described inspection apparatus in the present embodiment will be described.
[0044]
First, the inner ring 4 b of the ball bearing 4 to be inspected is attached to one end of the spindle rotating shaft 1. Next, the preload slider 23 is moved to a predetermined position, and the preload ring 22 is abutted against the outer ring 4a of the ball bearing 4 to be inspected as the preload slider 23 moves to the predetermined position. A predetermined preload is applied to the outer ring 4 a of the ball bearing 4 to be tested by the abutment of the preload ring 22. Further, the skew drive ring 21 is moved toward the steel ball 3 by air supply control to the cylinder chamber 24, and the tip of the small diameter portion of the skew drive ring 21 is abutted against the steel ball 3.
[0045]
When the abutting of the preload ring 22 and the abutting of the tip of the small diameter portion of the skew driving ring 21 are completed, the spindle rotating shaft 1 is rotated by the rotation driving motor, and the inner ring 4b rotates relative to the outer ring 4a. At the same time, the skew drive ring 21 is controlled and rotated so as to rotate with the periodic fluctuation as described above. In accordance with these rotations, each steel ball 3 rotates, with the axis B due to the preload applied to the outer ring 4a as a rotation axis, perpendicular to the rotation center axis of the spindle rotation shaft 1 and each point on the center axis. A component whose rotational speed changes is superimposed around an axis passing through the center of the steel ball 3 to cause a skew motion. By applying this skew motion, each time the steel ball 3 rotates once, the locus of the contact point with the outer ring 4a and the inner ring 4b of the steel ball 3 is slightly shifted on the steel ball 3, so that the steel ball 3 Of these, the contact area with respect to each groove of the outer rings 4b, 4a is almost the entire area of the steel ball surface. The degree of deviation of the trajectory is determined as appropriate because it is determined by the difference between the steel ball rotation period and the change component.
[0046]
Next, vibration or sound pressure generated from the ball bearing 4 to be inspected is measured in a state in which each steel ball 3 revolves with a skew motion, and the quality of the ball bearing 4 to be inspected is determined based on these measurement results. Determined.
[0047]
In the above embodiments, the change speed component given to the skew drive axis is a sine function. However, the change speed component is not limited to a sine function and may be a function that changes periodically.
[0048]
【The invention's effect】
  As described above, according to the ball bearing inspection method of the present invention, each of the ball bearings held between the groove of the inner ring and the groove of the outer ring.Rolling elementThe abutting part formed on the rotating body that rotates coaxially with the reference rotation shaft is abutted, and the reference rotation shaft is rotated while preloading the outer ring.Rolling elementRotating the rotating body while variably controlling the rotating speed of the rotating body so that theRolling elementBecause the physical quantity generated from the ball bearing to be inspected is measured while the head is skewing,Rolling elementIncludes measurement results of contact state with inner and outer grooves in almost all areas of the surface,Rolling elementFinish accuracy, surface scratchesRolling elementCan be inspected over the entire surface area. Therefore, the inspection accuracy for obtaining sufficient quality assurance for the ball bearing to be inspected can be remarkably improved.
  Moreover, according to the ball bearing inspection apparatus of the present invention, the same effects as described above can be obtained.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing a main part of an inspection device used in a first embodiment of a ball bearing inspection method of the present invention.
FIG. 2 is a block diagram showing a configuration of a motor controller in FIG.
FIG. 3 is a block diagram showing a main part of an inspection apparatus used in a second embodiment of the ball bearing inspection method of the present invention.
FIG. 4 is a configuration diagram showing a main part of a conventional ball bearing inspection apparatus.
FIG. 5 is a diagram schematically showing the state of rotation and revolution of a ball of a ball bearing inspected by the inspection apparatus of FIG. 3;
[Explanation of symbols]
1 Spindle rotation axis (reference rotation axis)
3 Steel balls
4 Ball bearing to be inspected
5,22 Preload ring
6 Preload spring
7 Skew drive shaft (rotating body)
7c Crash site
8,23 Preload slider
9 Skew drive motor
13 Motor controller
14 CPU
15 Function generator
16 F / V converter
17 Constant speed rotation command voltage generation circuit
18 Adder
20 spindle

Claims (4)

An inner ring of the ball bearing to be inspected is attached to a reference rotating shaft that rotates about its axis, and the inner ring is rotated by rotating the reference rotating shaft while preloading the outer ring of the ball bearing to be inspected in the axial direction. Rotating relative to the outer ring, measuring physical quantities such as vibration and sound pressure generated from the ball bearing to be inspected with relative rotation of the inner ring and the outer ring, and based on the result of the measurement, the ball In the ball bearing inspection method for inspecting a bearing, each rolling element held between the groove of the inner ring and the groove of the outer ring has a contact formed on a rotating body that rotates coaxially with the reference rotation shaft. Abutting a part, rotating the reference rotating shaft while applying the preload to the outer ring, and rotating the rotating body while variably controlling the rotating speed of the rotating body so that each rolling element performs a skew motion, each of the rolling elements Inspection method of the ball bearing, characterized by measuring said physical quantity generated from the inspection ball bearing in a state in which the skewed motion. The ball bearing inspection method according to claim 1, wherein the rotational speed of the rotating body is controlled to change periodically. A reference rotating shaft to which the inner ring of a ball bearing to be inspected composed of an inner ring and an outer ring and a plurality of spherical rolling elements interposed between the inner ring and the outer ring, a motor for rotating the inner ring by rotating the reference rotating shaft, An inspection apparatus for a ball bearing comprising a preload ring for applying a preload to the outer ring of the ball bearing to be inspected, the ball bearing inspection apparatus being provided so as to be movable in the axial direction of the reference rotating shaft, and having one end projecting against the plurality of rolling elements. An inspection apparatus for a ball bearing, comprising skew drive means having a rotating body as a contact portion to be applied. The skew driving means includes a skew driving motor that rotates the rotating body coaxially with the reference rotation shaft, and a motor controller that controls the rotation speed of the rotating body by the skew driving motor to periodically change. The ball bearing inspection device according to claim 3, wherein

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