JP2017219127A - Rolling bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling bearing that allows a user to determine properly a degree of abnormality by obtaining accurately a wear amount and conduct an exchange work without leaving any remaining life.SOLUTION: A rolling bearing includes: a recess part in at least one of a raceway surface of an inner ring, a raceway surface of an outer ring and a rolling surface of a rolling element; and a coat for coating the raceway surface or rolling surface while filling a front part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rolling bearing, and more particularly to a rolling bearing capable of detecting its own wear state.

  Detecting abnormalities in rolling bearings is useful for determining the replacement time. For example, sound and vibration from an operating rolling bearing are measured and frequency analysis is performed, and when the reference peak value is exceeded, it is determined that the rolling bearing has an abnormality and is replaced.

  In the patent document 1, the present applicant also measures the sound and vibration from the rolling bearing to generate the actual frequency spectrum data, and the frequency of the peak appearing point above the reference level on the actual frequency spectrum data is the bearing specification. Compared to the peak due to the abnormality of the part, when the frequency of the peak appearing point above the reference level on the measured frequency spectrum data matches the fundamental frequency, it is below the fundamental frequency on the measured frequency spectrum data. Check for the presence of frequency components with peaks above the reference level in the low frequency range, and if the measured frequency spectrum data has peaks above the reference level in the low frequency range below the fundamental frequency, further reduce the frequency range below the fundamental frequency. Compare whether or not the harmonics of the frequency components with peaks above the reference level match the fundamental frequency. Diagnose that there is an abnormality in a specific part of the bearing when harmonics of frequency components having peaks above the reference level in the low frequency range below the frequency do not match the fundamental frequency, and diagnose that there is no abnormality in the specific part of the bearing when they match. We propose a diagnostic method. According to this abnormality diagnosis method, it is possible to reduce the calculation load for abnormality diagnosis and perform accurate abnormality diagnosis in a short time.

Japanese Patent No. 3846560

  However, although the method of Patent Document 1 can detect an abnormal part, it is difficult to detect the degree of abnormality, for example, the wear amount of the abnormal part. For this reason, when an abnormality is detected, bearing replacement may be carried out with an emphasis on safety regardless of the degree of abnormality such as the amount of wear and the like, with a life remaining.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a rolling bearing that can accurately determine the amount of wear, accurately determine the degree of abnormality, and perform replacement work without leaving a lifetime.

In order to solve the above problems, the present invention provides the following rolling bearing.
(1) In a rolling bearing in which a plurality of rolling elements are arranged between an inner ring and an outer ring,
And at least one of the raceway surface of the inner ring, the raceway surface of the outer ring and the rolling surface of the rolling element has a recess, and
A rolling bearing characterized in that a coating covers the raceway surface or the rolling surface while filling the recess.
(2) The rolling bearing according to (1), wherein the recesses are formed at equal intervals along one direction.
(3) The rolling bearing according to (1) or (2) above, wherein the concave portion is a plurality of types having different opening areas and depths from each other.

  According to the rolling bearing of the present invention, when the sound and vibration from the bearing are measured during the operation of the bearing and when a signal representing a specific sound or vibration derived from the recess formed on the raceway surface or the rolling surface is detected, It is determined that the wear has progressed to the concave portion, and the bearing can be replaced at an appropriate time so as not to leave a lifetime based on the wear amount.

It is a schematic diagram which shows the example which formed the recessed part in the inner ring raceway surface of the ball bearing. It is a schematic diagram which shows the other example of a recessed part. FIG. 3 is a schematic diagram showing a state in which the inner ring raceway surface shown in FIGS. 1 and 2 is covered with a coating. It is a schematic diagram which shows the example which formed the recessed part in the outer ring raceway surface of a ball bearing. It is a schematic diagram which shows the other example of a recessed part. It is a schematic diagram which shows the state which coat | covered the outer ring raceway surface shown in FIG.4 and FIG.5 with the film. (A) is a schematic diagram which shows the example which formed the recessed part in the rolling surface of the ball | bowl of a ball bearing, (B) is a schematic diagram which shows the state which coat | covered the ball with the film. (A) is a schematic diagram which shows the example which formed the recessed part in the rolling surface of the cylindrical roller of a cylindrical roller bearing, (B) is a schematic diagram which shows the state which coat | covered the cylindrical roller with the film. (A) is a schematic diagram which shows the example which formed the recessed part in the rolling surface of the tapered roller of a tapered roller bearing, (B) is a schematic diagram which shows the state which coat | covered the tapered roller with the film. It is a drawing substitute photograph which shows the other example of a recessed part. It is a drawing substitute photograph which shows another example of a recessed part. It is a drawing substitute photograph which shows another example of a recessed part. It is a drawing substitute photograph which shows another example of a recessed part. It is a drawing substitute photograph which shows another example of a recessed part.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  In the present invention, the type of rolling bearing is not limited, but a recess is formed in at least one of the inner ring raceway surface, the outer ring raceway surface, and the rolling element rolling surface, and the raceway surface or The entire rolling surface is covered.

  For example, FIG. 1 is a schematic view showing an example in which a concave portion 10 (hereinafter referred to as “circular concave portion 10”) having a circular opening is formed on an inner ring raceway surface 1a of an inner ring 1 of a ball bearing. The opening diameter and depth of the circular recess 10 may be the same for all of the plurality of circular recesses 10, but are preferably different. As will be described later, by using the rolling bearing of the present invention, it is possible to determine a worn portion by detecting a specific sound or vibration signal derived from the circular recess 10, but the circular recess 10 having a different opening diameter and depth is used. By providing, the amount of wear can be detected more finely. For example, in FIG. 1, a plurality of circular concave portions 10 having the same opening diameter and a depth of 0.5 μm are arranged at equal intervals in the circumferential direction, and a plurality of circular concave portions 10 having a depth of 5 μm are arranged in the circumferential direction. By arranging them at intervals, the amount of wear can be detected in two stages. Also, the opening diameter may be changed between the circular recess 10 having a depth of 0.5 μm and the circular recess 10 having a depth of 5 μm. Further, for example, the 0.5 μm circular recesses 10 may be differentiated at intervals of 30 °, and the 5 μm circular recesses 10 may be differentiated at intervals of 60 °, for example, so that the respective frequencies can be easily specified. Of course, even intervals may be used.

  FIG. 2 shows a case where the recesses 11 whose openings are linear (hereinafter “linear recesses 11”) are formed at equal intervals in the circumferential direction. The plurality of linear recesses 11 may all have the same depth, but for the same reason as described above, it is preferable to use a plurality of types having different line widths and depths.

  As a method of forming the circular recess 10 or the linear recess 11, mechanical processing such as shot blasting, shot peening, marking needle, laser processing, chemical etching using an acid aqueous solution or an alkaline aqueous solution, and the like are possible. Its depth can be adjusted.

  Then, as shown in FIG. 3, the entire inner ring raceway surface 1 a is covered with a coating 20. At that time, the circular recess 10 and the linear recess 11 are filled with the coating 20. Therefore, the coating film 20 is formed to be thick to some extent so that the circular recess 10 and the linear recess 11 can be filled. Further, the surface of the coating 20 may be polished or superfinished.

  Since the coating 20 becomes the inner ring raceway surface 1a, the coating 20 is preferably made of a material having wear resistance and slidability, such as hard chromium, nickel, manganese phosphate, zinc phosphate, DLC (diamond-like carbon), etc. A membrane consisting of Moreover, the film-forming method of the film 20 is appropriately selected depending on the film material, and is formed by vapor deposition, plating, chemical conversion treatment, or the like. Specifically, a hard chromium film or a DLC film can be formed by vapor deposition or sputtering, a nickel film can be formed by electroless plating, and a manganese phosphate film or a zinc phosphate film can be formed by chemical conversion treatment, respectively. And the film thickness of the film 20 is adjusted with film-forming conditions. In particular, the coating 20 is preferably harder than the raceway surface. This is because when the coating film 20 is completely worn out, the bearing base material wears more than the coating film filled in the recesses, so that the filled coating film protrudes and becomes a vibration source.

  Moreover, you may form a recessed part in an outer ring raceway surface. That is, as shown in FIGS. 4 and 5, a circular recess 10 and a linear recess 11 are formed on the outer ring raceway surface 2a of the outer ring 2 in the same manner as described above, and coated with a coating 20 as shown in FIG. To do.

  Furthermore, you may form a recessed part in the rolling surface of a rolling element. FIG. 7 shows a case of a ball bearing. In FIG. 7A, a circular recess 10 is formed on the rolling surface of the ball 3 in the same manner as described above, and the entire surface is covered with a coating 20 as shown in FIG. ,Grind. FIG. 8 shows a case of a cylindrical roller bearing. In FIG. 8A, a circular recess 10 is formed on the rolling surface of the cylindrical roller 4 in the same manner as described above, and the entire surface is covered with a coating 20 as shown in FIG. Cover and polish. FIG. 9 shows a case of a tapered roller bearing. In FIG. 9A, a circular recess 10 is formed on the rolling surface of the tapered roller 5 in the same manner as described above, and the entire surface is covered with a coating 20 as shown in FIG. Cover and polish.

  In addition, for example, as shown in FIG. 10, a concave portion in which lines of a V-shaped cross section are arranged at equal intervals, a concave portion in a grid shape as shown in FIG. 11, and a concave portion in which disks are arranged in a lattice shape as shown in FIG. As shown in FIG. 13, recesses with various patterns and shapes, such as recesses in which squares are arranged in a line as shown in FIG. It can be formed on the rolling surface and filled with a coating.

  As described above, by using the rolling bearing of the present invention including the inner ring 1, outer ring 2, and rolling element 3 having recesses and coatings formed on the raceway surface and the rolling surface, the wear amount is accurately determined when evaluating the bearing life. Therefore, it is possible to obtain an appropriate replacement time without leaving a lifetime. The bearing life can be evaluated according to a known method for measuring sound and vibration from a rotating bearing (see, for example, Patent Document 1). Here, as shown in FIG. 1, circular recesses 10 having the same opening diameter and a depth of 0.5 μm are arranged in the upper row, and circular recesses 10 having a depth of 5 μm are arranged in the lower row to form a film 20. An example of a rolling bearing provided with an inner ring raceway surface 1a whose surface is polished will be described below.

  First, the rolling bearing is rotated, and at the same time, sound or vibration from the bearing is measured. The raceway surface of the rolling bearing gradually wears with rotation, and after the coating 20 on the inner ring raceway surface 1a is completely worn, the first vibration derived from the circular recess 10 having a depth of 0.5 μm and the depth of 5 μm. Both of the second vibrations derived from the circular recess 10 are detected. As the bearing continues to rotate, the first vibration disappears, and only the second vibration is eventually detected. As described above, the period in which neither the first vibration nor the second vibration is detected immediately after the rotation is a period in which the coating 20 remains, and it can be determined that there is little wear and there is a considerable time until the replacement time. . Further, when both the first vibration and the second vibration are detected, it can be determined that the wear amount is 0.5 μm or less, and when only the second vibration is detected, the wear amount is 0.5 μm. It can be judged that it is over. When the second vibration is no longer detected, it can be determined that the wear amount exceeds 5 μm. As described above, by using the rolling bearing of the present invention, the wear amount of the rotating rolling bearing during rotation can be more precisely and accurately known.

  The life of a rolling bearing is determined by the amount of wear of the inner and outer rings and rolling elements, and the allowable amount of wear according to the type of rolling bearing and usage conditions is empirically known. Since the amount of wear can be known from the depth of the recess as described above, replacing the bearing when the amount of wear is close to the allowable wear amount, ensuring safety while replacing the remaining life. It becomes possible to do.

DESCRIPTION OF SYMBOLS 1 Inner ring 1a Inner ring raceway surface 2 Outer ring 2a Outer ring raceway surface 3 Rolling element 4 Cylindrical roller 5 Tapered roller 10 Circular recessed part 11 Linear recessed part 20 Coating

Claims (3)

In a rolling bearing in which a plurality of rolling elements are arranged between an inner ring and an outer ring,
And at least one of the raceway surface of the inner ring, the raceway surface of the outer ring and the rolling surface of the rolling element has a recess, and
A rolling bearing characterized in that a coating covers the raceway surface or the rolling surface while filling the recess.   The rolling bearing according to claim 1, wherein the recesses are formed at equal intervals along one direction.   The rolling bearing according to claim 1, wherein the concave portion is a plurality of types having different opening areas and depths from each other.