JPH07324972A - Vibration measuring device for rolling bearings - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a vibration measuring device capable of accurately measuring vibration of a rolling bearing. [Structure] The vibration measuring device 1 includes a shrink chuck 5,
A vibration pickup 41 is attached to the outer periphery of a jaw 5a that holds the outer ring 4 of the roller bearing 2 by using the spindle 14 and the servomotor 16 as mechanical elements. An annular groove 5b is formed on the inner surface of the jaw 5a that holds the bearing 2, and the shell 1 having hydraulic pressure as a back pressure is formed in the annular groove 5b.
8 is fitted. For vibration measurement, shell 18
It is possible to prevent the shock vibration from being generated by so-called "roller drop" by increasing the hydraulic pressure of the so that the bearing clearance becomes zero.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling bearing vibration measuring apparatus for detecting vibration of a rolling bearing (variation of displacement, velocity, acceleration and elastic wave).

[0002]

2. Description of the Related Art Conventionally, as a vibration measuring device for a rolling bearing, a driving means for rotationally driving an outer ring or an inner ring, a vibration pickup for detecting a vibration or an elastic wave of the outer ring or the inner ring, and a signal detected by the vibration pickup are analyzed. There is known a device provided with a frequency converter that operates.

The vibration measuring device having the above-mentioned structure analyzes the detected vibration (variation of displacement, velocity, acceleration and elastic wave (AE signal)) and, for example, the race ring (inner ring or outer ring) or rolling of a rolling bearing. Check the rolling surface of moving bodies (various rollers or balls) for scratches, surface roughness, waviness, shape defects and the presence of foreign matter, and monitor the bearing for abnormalities in durability tests.

This conventional vibration measuring device applies a radial load or a moment load to the outer ring of a bearing having no contact angle (for example, a cylindrical roller bearing, a needle bearing, a ball or roller type water pump bearing, etc.) to locally The bearing is driven in a state where the clearance between rolling elements such as rollers and the bearing ring is eliminated, and the vibration of the bearing alone is evaluated.
Further, for a bearing having a contact angle (for example, a ball bearing, etc.), the bearing is driven under a load in the axial direction according to the dimension of the bearing, and the vibration of the bearing itself is evaluated. .

[0005]

However, the conventional rolling bearing vibration measuring apparatus has the following problems. In roller bearings and other bearings that do not have a contact angle, a radial or moment load is locally applied to the outer ring to partially form a load zone with no clearance between the rolling elements and the raceway shaft. On the other hand, in other parts, a non-loaded zone where a clearance is generated is formed between the rolling elements and the races. When the bearing is driven in this state, the rolling element collides with the bearing ring at the boundary where the rolling element transitions from the loaded zone to the non-loaded zone, a phenomenon called so-called "roller drop" occurs, which causes shocking vibration. To do. FIG. 8 is a graph of the measured vibration signal. It can be seen that a large peak signal i is generated due to the shocking vibration, and this is mixed with the information to be evaluated such as scratches on the rolling surface, which makes the vibration evaluation of the bearing difficult. Even if the impact is comparatively slight, the correct evaluation becomes difficult due to the slip of the rollers.

Further, in the conventional vibration measuring apparatus, it is possible to rotate the fixed ring little by little to move the load zone in order to evaluate the entire circumference of the fixed ring. There is also a problem that the vibration measuring device is configured to perform complicated control in order to repeat the measurement after rotating the fixed wheel.

On the other hand, there are also the following problems. When a bearing such as a ball bearing having a contact angle is attached to an actually used device, it is often used in an interference fit to prevent creep during operation. In such a state, the contact angle is reduced because the inner ring or outer ring is elastically deformed, and the running position of the rolling element such as a steel ball is displaced from the groove center of the race. The difference between the contact angle when evaluating the vibration of the bearing itself and that in practical use is often a problem, but until now there has been no effective means.

In order to solve the above problems, the dimensions of the fitting portion of the rolling bearing to be measured (the outer diameter of the mounting shaft to which the inner ring is fitted and the inner diameter of the housing in which the outer ring is mounted) are set to the rolling bearing. The bearing clearance in the fitted state is a specified value (zero for rolling bearings without a contact angle, and for rolling bearings with a contact angle, the contact angle is set in advance under a given axial load. The amount of clearance that gives the specified angle)
Extremely precise processing is required to finish to such dimensions. Further, even if the design dimensions are the same, the dimensions vary from rolling bearing to rolling bearing, so that it is difficult to fit the fitting portion each time the measurement target changes. Further, if the tightening margin is excessively large, deformation that affects the shapes of the races and rolling elements may occur, and correct evaluation may not be possible.

Therefore, an object of the present invention is to solve the above problems and to provide a vibration measuring device capable of accurately measuring the vibration of a rolling bearing.

[0010]

To achieve the above object, at least one vibration measuring device for a rolling bearing according to the present invention is provided.
Holding member into which one bearing ring and a rolling bearing having a plurality of rolling elements are fitted, and the rolling bearing fitted to the holding member are driven to roll the plurality of rolling elements with respect to the bearing ring. In a vibration measuring device for a rolling bearing, comprising: a driving unit for driving the rolling bearing; and a vibration detecting unit for detecting vibration of the rolling bearing, a deforming unit for uniformly elastically deforming a holding member fitted with the rolling bearing in a radial direction. And a fitting degree detecting means for detecting a state quantity indicating the fitted state of the rolling bearing and the holding member, and a bearing clearance amount according to the state quantity indicating the fitted state detected by the fitting degree detecting means. Deformation control means for permitting elastic deformation by the deformation means until a predetermined amount is reached.

[0011]

In the vibration measuring device for a rolling bearing according to the present invention, the rolling bearing is driven by the driving means in a state where the rolling bearing is fitted to the holding member to cause the plurality of rolling elements to roll with respect to the bearing ring. The vibration of the rolling bearing is detected by the vibration detecting means. At this time, the holding member fitted with the rolling bearing is elastically uniformly deformed in the radial direction by the deforming means, and the state quantity indicating the fitted state of the rolling bearing and the holding member is set by the fitting degree detecting means. The deformation control means permits the elastic deformation by the deformation means until the bearing clearance amount is detected and reaches a predetermined amount according to the detected state quantity indicating the fitted state.

Therefore, the shape of the bearing ring, which is deformed as the holding member is elastically deformed by the deforming means, is maintained,
The bearing ring can be elastically deformed uniformly in the radial direction, and the bearing ring contracts in the case of the outer ring and expands in the case of the inner ring. Thereby, the bearing clearance of the rolling bearing incorporated in the vibration measuring device is adjusted to a predetermined amount.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vibration measuring device for a rolling bearing according to the present invention will be described with reference to the drawings.

[First Embodiment] FIG. 1 is a schematic view showing a vibration measuring device for a rolling bearing according to a first embodiment. The vibration measuring device 1 of the present embodiment is configured with a known shrink type chuck 5 as a holding member, a spindle 14 and a servo motor 16 as main mechanical elements as claimed in the claims. The chuck 5 holds the roller bearing 2 to be measured, and the inner ring 3 of the roller bearing 2 has an arbor 13 attached to the tip of a spindle 14. The spindle 14 is connected to the rotary shaft of a servomotor 16 via a coupling 15. The spindle 14 and the servomotor 16 are configured to be movable in the axial direction by a slide mechanism such as a ball screw (not shown).

An annular groove 5b is formed on the inner surface of the outer ring restraining portion 5a for holding the roller bearing 2 of the chuck 5. FIG. 2 is a sectional view showing the structure of the outer ring restraint portion 5a. The annular groove 5b has a thin annular shell 18
Is mounted, the shell 18 is in contact with the outer ring 4 of the roller bearing 2, and contracts in the radial direction by receiving back pressure from a hydraulic device 21 described later. An annular groove 5 is provided inside the chuck 5.
A communication passage 5c is formed which connects b with the port 5d above it, and the communication passage 5c is held in an oil-tight state. The hydraulic device 21 is a booster 2 including a hydraulic cylinder.
3, a servo valve 25, a hydraulic pump 27, and a hydraulic controller 29 are provided to control the hydraulic pressure leading to the upper port 5d of the chuck 5.

The servo motor 16 is the servo controller 3
1 is an AC servomotor controlled by a rotary encoder 1, and a rotary encoder (not shown) is attached to its rotary shaft. The servo controller 31 is a computer 35
From the rotary encoder, and performs position feedback control and speed feedback control of the servo motor 16 according to the pulse signal from the rotary encoder.

A vibration pickup 41 as a vibration detecting means is attached to the outer surface of the outer ring restraint portion 5a of the chuck 5, and the vibration pickup 41 detects the vibration transmitted from the outer ring 4 in the radial and axial directions. Then, the signal is output to the signal measuring unit 45 including the amplifier unit 44 and the A / D converter 51. The amplifier section 44 includes an amplifier and a low-pass filter, and the signal amplified by the amplifier section 44 is sent to the A / D converter 46. Computer 35 is A /
The frequency of the vibration is analyzed based on the signal converted into the digital signal by the D converter 51.

Next, the measurement procedure of the rolling bearing vibration measuring apparatus of this embodiment will be described. At the time of measurement, the spindle 14 is retracted by the slide mechanism, the roller bearing 2 to be measured is inserted inside the outer ring restraining portion 5a of the chuck 5, and the spindle 14 is moved closer to the arbor 13 provided at the tip of the roller bearing. It fits into the inner ring 3 of 2.

Further, in order to reduce the bearing clearance of the roller bearing 2 to zero, the hydraulic device 21 is operated to contract the shell 18. The amount of shrinkage of the shell 18 depends on the shell 18 and the bearing 2
Of the outer ring 4 and the bearing clearance of the bearing 2. Further, the pressure required to shrink the shell 18 is based on the elastic deformation theory of the cylinder (see, for example, Mechanical Engineering Handbook, Vol. 4, Material Mechanics, P98-), for example, by FEM (Finite Element Method). It is derived from the relationship of the amount of displacement in the radial direction. In addition, the bearing clearance has a constant distribution, and the roller shrinkage conditions for one bearing are different from each other, so that the shell contraction condition at which the bearing clearance becomes zero differs depending on each bearing. Therefore, it is necessary to set the bearing clearance to zero and control the chuck pressure (back pressure of the shell 18) so that an excessive surface pressure is not generated between the roller and the raceway surface.

FIG. 3 is a flow chart showing a vibration measuring routine for controlling the chuck pressure. This vibration measurement routine is executed by the computer 35. First,
The computer 35 outputs the start of outer ring contraction to the hydraulic device 21 (step S1), and lightly clamps the outer ring 4 (step S2). The servomotor 16 is started up to a constant rotation while keeping the outer ring 4 held so as not to slip (steps S3 and S4). Then, the computer 35
Outputs a pressure increase signal to the hydraulic device 21 and gradually increases the chuck pressure (steps S5 and S6), and the bearing torque changes.

FIG. 4 is a graph in which the bearing torque changes with the chuck pressure. When the chuck pressure is between a and b, the roller bearing 2 is in a clearance state, and the bearing torque is mainly viscous resistance of grease. Further, when the chuck pressure increases and the roller and the bearing ring start contact with each other at point b, the torque suddenly increases. Since the increase in the bearing torque suddenly becomes smaller when point c is exceeded, it can be considered that almost all the rollers come into contact at this inflection point c. The chuck pressure is held at this inflection point c (step S7), the vibration from the roller bearing 2 is detected by the vibration pickup 41, and well-known signal processing is performed to make a determination (step S8). Here, step S5
The bearing torque in S6 can be obtained by monitoring the armature current of the servomotor 16. That is, as is well known, the armature current of the motor is proportional to the load torque. Utilizing this fact, the proportional constant for obtaining the value of the load torque is obtained in advance from the armature current of the servo motor 16 and stored in the memory of the computer 35. The computer 35 uses the armature current value input from the servo controller 31. Is multiplied by the proportional constant to obtain a load torque value. Further, the computer 35 fetches the armature current continuously input at every predetermined sampling cycle (a cycle sufficiently small with respect to the chuck pressure increasing speed and considering the time required for the above calculation and the torque check calculation). , The above calculation is repeated. As a method of determining whether or not the point c has been reached, for example, it is reached at a time when a predetermined torque value (a torque value corresponding to a point as close to the c side as possible between b and c in FIG. 4) is exceeded in advance. How to judge,
There is a method of making a judgment by observing the fluctuation of the difference from the previous measured value. Further, as described above, the load torque is proportional to the armature current, and the absolute value of the load torque is not necessary (it suffices to know the inflection point c in FIG. 4). Therefore, the above calculation is omitted. However, the above-described determination method may be applied directly to the armature current (which is substantially the same as knowing the bearing clearance state from the change in load torque). When the measurement is completed, the driving of the servo motor 16 is stopped (step S9), the chuck pressure is released (step S10), and this routine is completed.

In the first embodiment, the state quantity indicating the fitted state of the rolling bearing according to claim 1 is the bearing torque, and the predetermined value of the bearing clearance amount in the fitted state is zero.

According to the vibration measuring apparatus 1 of this embodiment, it is possible to prevent a so-called "roller drop" in which the roller and the bearing ring collide,
A correct vibration evaluation can be obtained.

[Second Embodiment] Next, a vibration measuring device for a rolling bearing according to a second embodiment will be described. FIG. 5 is a sectional view showing the mechanical structure of the vibration measuring apparatus according to the second embodiment.
Unlike the roller bearing which is the measurement target of the first embodiment, the vibration measuring device 51 of the present embodiment targets a ball bearing as the measurement target. FIG. 6 is a sectional view showing the structure of the ball bearing 52. The ball bearing 52 is a type of rolling bearing having a contact angle α, and is a raceway 53 a of the outer ring 53, the inner ring 55 and the outer ring 53.
And a plurality of balls 5 as rolling elements between the inner race 55 and the raceway 55a.
Have six. The vibration measuring device 51 includes a spindle 67, an outer ring pressing device 84, a booster 86 and a servo motor 69 as mechanical elements.

A taper hole is formed at the center of one end surface of the spindle 67, and the arbor 66 is fitted therein. An arbor 66 as a holding member in the claims which constitutes a known expanded type chuck is fitted to the inner ring 55 of the ball bearing 52. As the bearing structure 78 that rotatably supports the spindle 67, any structure may be used as long as it has a structure that does not generate vibration with the rotation of the spindle 67, such as a static pressure gas bearing, a magnetic bearing, and a superconducting bearing. .

Arbor 66 that contacts the inner ring 55 of the ball bearing 52
An annular groove 66b is formed on the side surface of the front end portion 66a of the, and a shell 74 is fitted on the outside of the annular groove 66b. A hydraulic communication passage 66c that deforms the shell 74 is formed inside the annular groove 66b.
A piston 72 is provided at the rear of the
By pressing 2, the hydraulic pressure in the communication passage 66c is adjusted. A booster 86 having a hydraulic cylinder 86a is provided at the rear of the piston 72. Hydraulic cylinder 86
Reference numeral a denotes a cylinder chamber 86c provided with a piston 86d, which receives hydraulic pressure from a hydraulic pressure generation circuit similar to that shown in FIG. 1 (not shown). Therefore, when the piston 72 is pushed by the booster 86, the shell 74 on the side surface of the tip end portion 66a of the arbor 66 in which the ball bearing 52 is fitted expands in the radial direction. The inner ring 55 of the ball bearing 52 also expands radially in response to the expansion pressure of the shell 74, and the contact angle α decreases.

The spindle 67 is a servo motor 69.
The belt 82 is stretched between the driven pulley 80 fixed to the rear portion of the spindle 67 and the drive pulley 81 fixed to the output shaft of the servomotor 69. The energization of the servomotor 69 causes the spindle 67 to rotate at a constant speed of, for example, about 1800 rpm.

The outer ring pressing device 84 is fixed so as to face the end surface of the outer ring 53 of the ball bearing 52 supported by the arbor 66. The outer ring pressing device 84 has a preload cylinder 84a, a swing joint 84b, and a pressing ring 84c. The rod 8 is attached to the preload piston 84d fitted in the preload cylinder 84a.
The base end of 4e is fixed, and the swing joint 84b is connected to the tip of this rod 84e. This swing joint 84b is 2
By sandwiching one sphere 84h between the plate pieces 84f and 84g, the plate pieces 84f and 84g can be freely rocked and displaced.

The pressing ring 84c is supported on the side surface of one plate piece 84f facing the ball bearing 52 via a cushioning material 84i. The pressing ring 84c is a preload cylinder 84a.
Is pressed against the end surface of the outer ring 53 of the ball bearing 52 as the pressure fluid is fed into the cylinder chamber 84j of the outer ring 5j.
3 is pressed in the axial direction. Even when the inner ring 55 is rotated by the energization of the servo motor 69 by this pressing,
The outer ring 53 is prevented from rotating and a predetermined axial preload is applied to the ball bearing 52.

The swing joint 84b has a function of pressing the pressing ring 84c against the end surface of the outer ring 53 with a uniform force over the entire circumference during the pressing operation. The cushioning material 84i causes vibration generated in the preload cylinder 84a and the swing joint 84b to occur in the outer ring 53.
To be transmitted to. The means for axially pressing the pressing ring 84c may be a solenoid or other mechanism instead of the preload cylinder.

The probe 83a of the vibration pickup 83 is in contact with the outer peripheral surface of the outer ring 53. The vibration pickup 83 measures the vibration transmitted to the outer ring 53 in the radial direction.
The vibration measuring device 51 of FIG. 5 shows only the mechanical element part, and drives the signal measuring part for measuring the output signal from the vibration pickup 83, the hydraulic cylinder 86a, the hydraulic device for driving the preload cylinder 84a, and the servomotor 69. Since the configuration of the servo controller to be used is the same as that of the first embodiment, the description thereof will be omitted.

Next, the measuring operation of the vibration measuring device 51 will be described. FIG. 7 is a flow chart showing the vibration measurement routine of the second embodiment. This routine is executed by the same computer (not shown) as in the first embodiment.

First, the outer ring pressing device 84 is driven to preload the outer ring 53 of the ball bearing 52 in the axial direction via the cushioning material 84i and the vibration-insulated pressing ring 84c (step S).
11). Subsequently, the servo motor 69 is driven to rotate the inner ring 55 of the ball bearing 52 (step S12). The vibration pickup 83 detects the radial vibration of the outer ring 53 caused by the rotation of the ball bearing 52 (step S13). The contact angle α is calculated based on the detected vibration signal (step S14). The calculation of the contact angle .alpha.
This is a well-known calculation method described in Japanese Patent No. 3644408. That is, the contact angle α is calculated by Equation 1.

[0034]

[Equation 1] Here, Da is the outer diameter of the ball 56, and dm is the pitch diameter of the orbit of the ball 56, so the values of Da and dm are known dimensions determined at the time of manufacturing. Also, fc, f
r is the revolution frequency of the ball 56 and the rotation frequency of the inner ring 53, respectively, and is a computer (not shown) for the following reasons.
Calculated by

The reason why the rotational frequencies of the balls 56 and the inner ring 55 are required will be described. Each member constituting the ball bearing 52 is finished with extremely high precision, but the surface shape and dimensions thereof have very slight errors. For example, the outer ring 5
The orbit of 3 is slightly eccentric with respect to the center of rotation. This eccentricity causes vibration in the rotational frequency component. By measuring the radial vibration of the outer ring 53, the inner ring 55
You can know the rotation frequency of. Further, although the outer diameters of the plurality of balls 56 incorporated in the ball bearing 52 should be the same, it is difficult to completely align the outer diameters due to manufacturing errors. The outer ring 53 vibrates in the radial direction due to the revolution of a plurality of balls 56 having slightly different outer diameters. Since the frequency of this vibration includes the revolution frequency component of the ball 52, the revolution frequency of the ball 56 can be obtained by determining the vibration frequency.

That is, when an arbor rotating at a constant rotation is inserted inside the inner ring of the bearing as disclosed in Japanese Patent Laid-Open No. 4-364408, the inner ring rotates together with the arbor, and the cage is rotated by the inner ring as the inner ring rotates. The rolling elements that are evenly arranged in the circumferential direction revolve in the rotation direction of the inner ring. At this time, the outer ring is stationary, and a vibration pickup for converting the vibration of the bearing into an electric signal is brought into contact with the outer peripheral surface of the outer ring.

The vibration detected by such a vibration pickup is obtained as a mixture of signals oscillating in the radial direction, the angular direction, and the axial direction due to the revolutions of a plurality of rolling elements and the waviness of the outer and inner ring raceways.

Since the frequencies of these vibrations coincide with the revolution cycle of the rolling element and the frequency which is an integral multiple of the revolution frequency fc of the rolling element, the frequency of the vibration changes from the revolution frequency fc.
Can be asked.

Then, if the frequency of the vibration of the outer ring or the inner ring in any of the above three directions is obtained, the revolution frequency fc
Since the inner ring rotation frequency fr (rev / sec, constant condition) is known, the known dm, Da
By giving, the relationship between fc and α can be calculated by Equation 1.

That is, it is known that fc can be obtained from one of the signals of the vibrations in the three directions obtained from the vibration pickup, and α can be calculated by calculating fc / fr by using Formula 1. .

The booster 86 applies pressure for deforming the shell 74 until the calculated contact angle α reaches a predetermined contact angle α A.
The piston 72 is controlled by pressing (steps S15, S16, S17), and when .alpha. =. Alpha.A, the pressure is held and the expansion of the inner ring 55 is maintained. The radial or axial vibration of the outer ring 55 of the ball bearing 52 is detected in a state where the inner ring 55 is inflated, and defects such as scratches and shapes existing in the bearing ring and the running trace of the steel ball are determined (step S1).
8).

When it is not necessary to set the axial load value to a predetermined value, the pressing force of the outer ring pressing device 84 may be controlled so that the contact angle α becomes a predetermined value.
That is, first, the bearing may be fitted by the booster 86, and then the contact angle α may be checked while increasing the pressing force of the outer ring pressing device 84. Examples of the checking method include a method of determining whether or not the contact angle α has reached a predetermined contact angle αA. Moreover, you may use both together.

Thus, the vibration measuring device 51 of this embodiment is
According to the above, it is possible to evaluate the vibration of the ball bearing alone under the fitting condition suitable for the actual use condition.

In the second embodiment, the state quantity indicating the fitted state of the rolling bearing according to claim 1 is the rotation frequency of the inner ring and the revolution frequency of the ball, and the contact angle calculated from these, and the fitted state. The predetermined value of the bearing clearance amount in is a unique clearance amount corresponding to the case where the contact angle under a predetermined axial preload is a predetermined value.

In each of the above embodiments, as the vibration detecting means, for example, an AE sensor, a piezoelectric element, an optical displacement meter, a speedometer, an accelerometer or the like can be used. Also,
It may be installed in multiple positions, or it may be installed at symmetrical positions on the outer ring to increase the detection accuracy by subtracting common noise signals other than vibration, or it may be installed on the side of the bearing ring to detect axial vibration. Good. Further, although the outer ring is compressed and the inner ring is expanded by using the hydraulic device in this embodiment, a collet chuck may be used instead of the hydraulic device.

In the first embodiment, the object to be measured is a cylindrical roller bearing, but any other type of rolling bearing may be used as long as it has no contact angle, for example, a needle bearing without an inner ring. Etc. can also be targeted. Further, in this embodiment, the deforming means is provided in the housing, but the outer diameter of the arbor as in the second embodiment may be expanded. Although the inner ring is driven, the inner ring may be fixed and the outer ring may be rotated to measure the vibration of the inner ring.

In the second embodiment, the object to be measured is an angular contact ball bearing, but any other type may be used as long as it has a contact angle, and other than ball bearings such as deep groove ball bearings. It can also be applied to tapered roller bearings. Further, the outer ring may be fitted in the housing and the deforming means may be provided in the housing. Other than that, the same changes as in the first embodiment can be made.

Further, the state quantity indicating the fitted state and the means for detecting the state are not limited to those in the above-mentioned respective embodiments, and may be any one that can uniquely derive the bearing clearance from the state quantity. For example, in the first embodiment, the torque may be detected by another method (for example, a strain gauge or the like is used).

That is, a deformation control means for controlling the housing or the mounting shaft to be uniformly deformed in the radial direction so that the bearing clearance of the rolling bearing to be measured in a state of being fitted in the vibration measuring device becomes a predetermined value. It does not depart from the scope of the present invention as long as it has it.

[0050]

According to the vibration measuring device for a rolling bearing of the present invention, the bearing ring is elastically deformed uniformly in the radial direction without breaking the shape of the bearing ring, and the bearing clearance of the rolling bearing is set to a predetermined amount. Since the rolling bearing is driven by the driving means in the adjusted state and the vibration of the rolling bearing is detected by the vibration detecting means, the vibration of the rolling bearing can be accurately measured.

That is, in a bearing having no contact angle, such as a cylindrical roller bearing, a load zone can be formed over the entire circumference of the bearing ring, and all rolling elements can be reliably contacted with the bearing ring with no clearance. Obtainable. As a result, the impact due to the so-called "roller drop" phenomenon disappears, and the transfer surface between the race of the outer ring and the race of the inner ring on which the rolling element rolls is scratched or foreign matter is mixed in. Defects can be detected with high accuracy.

At the same time, the local contact between the rolling element and the bearing ring causes the contact around the entire circumference, so that the defect on the contact surface between the bearing ring and the rolling element can be reliably detected. It enables evaluation over the entire circumference. Therefore, as compared with the case where the fixed wheel is rotated to move the load zone and the measurement is repeated, the measurement time can be shortened and the control configuration can be simplified.

Further, in the case of a bearing having a contact angle such as a ball bearing, the contact angle of the bearing at the time of measurement can be aligned with the contact angle in the fitted state such as an interference fit that is actually used. It is possible to evaluate the vibration of a single bearing that conforms to.

[Brief description of drawings]

FIG. 1 is a configuration diagram schematically showing a vibration measuring device for a rolling bearing according to a first embodiment.

FIG. 2 is a sectional view showing a structure of an outer ring restraint portion 5a.

FIG. 3 is a flowchart showing a vibration measurement routine for controlling chuck pressure.

FIG. 4 is a graph showing changes in bearing torque with respect to chuck pressure.

FIG. 5 is a sectional view showing a configuration of a vibration measuring device according to a second embodiment.

6 is a sectional view showing the structure of a ball bearing 52. FIG.

FIG. 7 is a flowchart showing a vibration measurement routine of the second embodiment.

FIG. 8 is a schematic diagram of a vibration signal measured with a bearing clearance.

[Explanation of symbols]

 1 ... Vibration measuring device 2 ... Roller bearing 3 ... Inner ring 4 ... Outer ring 18 ... Shell 21 ... Hydraulic device 41 ... Vibration pickup 45 ... Signal measuring unit

Claims (1)

[Claims] 1. A holding member into which a rolling bearing having at least one bearing ring and a plurality of rolling elements is fitted, and the rolling bearing fitted into the holding member is driven to move the rolling bearing with respect to the bearing ring. In a vibration measuring device for a rolling bearing, comprising: a driving means for rolling a plurality of rolling elements, and a vibration detecting means for detecting vibration of the rolling bearing, a holding member fitted with the rolling bearing is arranged in a radial direction. Deforming means for elastically deforming, a fitting degree detecting means for detecting a state quantity indicating a fitting state of the rolling bearing and the holding member, and a state quantity indicating a fitting state detected by the fitting degree detecting means. And a deformation control means for permitting elastic deformation by the deforming means until the amount of bearing clearance corresponding to a predetermined amount reaches a predetermined amount.