JPS63111309A - Rolling element - Google Patents

Abstract

PURPOSE:To prevent any local abrasion on the rolling element in the caption by locally providing ring-shaped grooves inside the rolling contact surface of a rolling element for reducing concentration of contact stress in a contact portion. CONSTITUTION:At both axial end portions of the contact portion of a rolling element 21 to a rotor 11, ring-shaped grooves 22 which are concentric with a rolling contact surface are engraved respectively from the end face inside the rolling contact surface of the rolling element 21. When the rolling element 21 and the rotor 11 are brought in contact with each other so as to be pressed and rotated together, contact stress is concentrated at both axial end portions 23 of the contact portion of the rolling element 21. But the rigidity is reduced by the grooves 22 so that both end portions 23 of the rolling element 21 may be easily subjected to elastic deformation. Accordingly, the stress concentration generated at the end portions by said local elastic deformation is relaxed, and therefore local abrasion can be prevented.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a rolling element having one central axis, such as a backup roll of a roller leveler for flattening a rolled plate, a general-purpose roller bearing, or a roller of a flat cage. It is suitable for use in rolling elements such as.

<Prior Art> As shown in FIG. 5, a roller-shaped rolling element 12 that rotates while being pressed against a contacting rotating body I+ with a predetermined surface pressure generally has a roller-shaped rolling element 12 on both axial edges of its rolling surface. By adding a chamfer 13 or rounding the edge, damage caused to the contact rotating body II is reduced.

<Problems to be Solved by the Invention> However, when the rolling element 12 is brought into contact with and pressed against the contacted rotating element 11, the contact stress distribution on the rolling surface of the rolling element 12 is as shown in the lower part of FIG. It shows a tendency to rise steeply at the edges. For this reason, even if the edges are chamfered or rounded, wear, surface scratches, pitting, plastic deformation, etc. are likely to occur at the contact area, and the load acting on the edges tends to increase the strength. is regulated, so the load capacity of the rolling elements 12! The problem was that it was not possible to take large detours.

The present invention has been made in view of this problem, and an object of the present invention is to provide a rolling element that prevents a sudden increase in contact stress at the edge of the rolling surface.

<Means for solving the gap> The rolling element according to the present invention to solve such problems is a roller-shaped rolling element that rotates while being pressed against a contact object. , a ring-shaped groove concentric with the rolling surface is formed inside the rolling surface at both ends in the axial direction of the contact portion for the contacted body.

<Function> The rigidity of the portion where the ring-shaped groove is formed is reduced, and the rolling surface thereof becomes more likely to be elastically deformed. Since the rigidity is reduced at both axial ends of the contact portion where contact stress is most likely to be concentrated when the rolling element contacts and presses the contact object and rotates,
The concentration of contact stress is alleviated.

Example of implementation Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a conceptual diagram showing a rolling element according to the present invention, a contacting rotating element that comes into contact with the rolling element, and a contact stress distribution thereof. In FIG. 1, the rolling element 2I has a roller shape with one central axis, and the contacting rotating element l! It rotates while being pushed. At both ends in the axial direction of the contact portion of the rolling element 21 with respect to the contacted rotating element H, a ring-shaped ring is provided on the inner side of the rolling surface (outer peripheral surface) of the rolling element 2I and is concentric with the rolling surface, that is, centered on the central axis. Grooves 22 are recessed from each end. This groove 2
2 is formed close to the outer circumferential surface and has a depth corresponding to the range where contact stress concentration occurs at the rim,
This groove 22 forms a thin portion with a uniform thickness on the outer periphery.

In such a rolling element 21, when the contacting rotating element (2) and the contacting rotating element (2) come into contact with each other and are pressed and rotate together, contact stress is concentrated at both axial ends 23 of the contact portion of the rolling element 21. Since the rigidity of the portion 23 is reduced by the groove 22 and it is easily elastically deformed, the stress concentration generated at the end portion is alleviated by the local elastic deformation. As a result, as shown in the lower part of FIG. 1, a near-straight and flat contact stress distribution with no sudden increase in stress at the edges is obtained.

Next, an example in which the rolling element 21 according to the present invention is used in an actual machine will be described.

FIG. 2 is a schematic side view of a roller leveler using rolling elements according to an embodiment of the present invention, and FIG. 3 is a partially cutaway enlarged front view of the main part thereof. In FIGS. 2 and 3, reference numeral 31 denotes a rolling element according to the present invention used as a backup roll, and as described above, ring-shaped grooves 32 having a U-shaped cross section are formed on both axial end faces.

The rolling elements 31 include three rows of rollers 33 provided in a plurality in the circumferential direction.
The rollers are rotatably attached to the fixed shaft 34 via the rollers, and a plurality of rollers are arranged along the roll axis direction of the work roll 35 to support the work roll 35. On the other hand, the fixed shaft 34 is fixed to a roll carriage 37 via a saddle 36.

These work rolls 35, rolling elements (backup rolls) 31, roll carriages 37, and the like are provided above and below the metal plate 38 with the passageway between them.

In such a roller leveler 39, the work roll 3
The deflection due to the rolling reaction force of No. 5 is supported by each rolling element 31, and as a result, blood pressure acts on both, and contact stress is concentrated at the location where both ends of the rolling element 31 contact the work roll 35. The thin wall portion between the outer peripheral surface of the groove 32 and the groove 32 is locally elastically deformed to relieve the stress concentration. Therefore, by flattening the contact stress distribution, damage to the work roll 35 and damage to the rolling element 31 itself can be reduced, and the frequency of repair of the roller leveler 39 can be reduced to improve work efficiency.

Moreover, FIG. 4 is a longitudinal sectional view of a roller bearing using rolling elements according to an embodiment of the present invention. In FIG. 4, reference numeral 41 indicates a rolling element according to the present invention used as a roller of a roller bearing, and reference numeral 42 indicates a ring-shaped groove formed on both end faces in the axial direction. A plurality of rolling elements 41 are sandwiched between an outer ring 43 and an inner ring 44 to form a roller bearing 45, similar to conventional rollers.

Also in this embodiment, due to the action of the grooves 42, the rolling elements 41
an outer ring 43, an inner ring 44 at the end of
and damage to the rolling element 41 itself can be reduced,
It becomes possible to maintain high stiffness of the roller bearing 45 over a long period of time.

<Effects of the Invention> As described above in detail with reference to the embodiments, according to the present invention, a ring-shaped structure that locally reduces the rigidity is provided inside the rolling surface at both axial ends of the contact portion of the rolling element. Since we created a groove for
The contact stress concentration at the edge of the contact portion is significantly reduced, thereby making it possible to prevent local wear, surface scratches, pitting, and plastic deformation at the edge.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram showing a rolling element according to the present invention, a contact rotating body that contacts the same, and the contact stress distribution thereof, and FIG. 2 is a schematic side view of a roller leveler using a rolling element according to an embodiment of the present invention. , Fig. 3 is a partially cut-away enlarged front view of the main part, Fig. 4 is a longitudinal sectional view of a roller bearing using rolling elements according to an embodiment of the present invention, and Fig. 7irJS shows a rolling element according to a conventional example. FIG. 2 is a conceptual diagram showing a contact rotating body that comes into contact with the rotating body and its contact stress distribution. In the drawings, 21.31.41 is a rolling element, and 22.32.42 is a ring-shaped groove.

Claims (1)

[Claims] In a roller-shaped rolling element that rotates while being pressed against a contact object, a ring-shaped groove concentric with the rolling surface is formed on the inner side of the rolling surface at both axial ends of the contact portion with respect to the contact object. A rolling element characterized by being formed.