JPS60188622A - Roller bearing - Google Patents

Abstract

PURPOSE:To ensure secure lubrication and smooth rotation by both circumferential edges of bearings in pocket holes in a cage serving as magnetic poles different from each other to hold concentrically magnetic fluid. CONSTITUTION:A plurality of rollers 4 attached between inner and outer rings 2, 3 are received in a plurality of pocket holes in a cage 1 so that the rollers 4 are held at a predetermined interval and the circumferential edges 1a, 1b of the pocket hole are magnetized to have polarity different from each other respectively. Thus, magnetic lines of force 6 extend from the circumferential edge adjacent the respective pocket holes on the cage 1 toward the roller 4. When magnetic fluid is enclosed in the bearing, strong magnetic field gradient is produced in spots necessary for lubrication within the cage pocket hole by the magnetic line of force so that the magnetic fluid is concentrically held in these spots to ensure secure lubrication and smooth rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rolling bearing in which a magnetic fluid is held inside the bearing and the rolling elements of the bearing are lubricated by the magnetic fluid.

In roller bearings such as ball bearings and roller bearings, lubricant is supplied between the rolling elements of the steel balls or rollers and the raceway surfaces of the inner and outer rings to ensure smooth relative rotation between the inner and outer rings. However, in order to retain this lubricant inside the bearing, manganese zinc iron oxide (Mn Zn 0 - FeiOs) is used.
A magnetic fluid containing fine magnetic particles such as colloid in a non-magnetic oil carrier is used as a lubricant, and lines of magnetic force are generated inside the bearing, and the magnetic fluid is drawn into the bearing by the lines of magnetic force. There is. For example, as shown in Fig. 1(a) K, the cage 1 holding the rolling elements 4 is magnetized as is, and as shown in Fig. 1(b), the inner and outer rings 2, 3 themselves are directly magnetized. It is being In these structures, especially in the case of FIG. 1(a), the magnetic fluid is not sufficiently retained on the rolling surfaces 4a, 4b of the rolling elements 4. In addition, in the example shown in FIG. 1(b), the inner ring 2 is magnetized, but magnetic poles are generated on both end faces of the inner ring 2, and the rolling elements 4
The contact surface 2a is at the center of the magnet, and the magnetic force at this part is not very strong. Particularly in the case of roller bearings, the magnetic fluid is held only on the end surfaces of the rollers, and is rarely held on the peripheral surfaces of the rollers, that is, the rolling surfaces. 1st
As shown in Figure (e), roller bearings in which the inner ring 2 or outer ring 3 is magnetized are not suitable because the lines of magnetic force do not pass through the transfer surface.
It has almost no effect. Also, as shown in Fig. 2, a structure in which magnets 5 are embedded in the rolling elements 4 or the rolling elements themselves are magnetized is also known, but the direction of the magnetic lines of force changes constantly during use of the bearing, and it is necessary to The magnetic fluid is not always retained in the correct location.

Compared to the conventional structure described above, the present invention can concentrate and retain magnetic fluid much more reliably on the contact area between the inner and outer ring raceway surfaces in the bearing and/or the pocket surface of the cage and the rolling elements, resulting in low torque. The purpose of the present invention is to provide a roller bearing that provides stable high-speed rotation performance without uneven rotation.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 is an end view of a roller bearing according to an embodiment of the present invention, and FIG. 4 is a partial perspective view of the embodiment of FIG. 3 with the outer ring removed. In this embodiment, a plurality of rollers (
The rolling elements) 4 are housed in a plurality of pocket holes of a cage l, thereby holding the rows 24 at a predetermined interval. It is magnetized so that alternating 1C8 poles and N poles occur in 1a and 1b. That is, both circumferential directions of each pocket hole have different magnetic poles from each other.

Therefore, the lines of magnetic force extend from the adjacent circumferential edges of each pocket hole of the cage 1 toward the rolling elements 4 as shown by the reference numeral 6, and when the magnetic fluid is sealed in the trap in the bearing, the lines of magnetic force cause lubrication in the pocket hole of the cage. A strong magnetic field gradient is generated at the required location, and the magnetic fluid is concentrated and held in this area.
This provides reliable lubrication and smooth rotation.

Although this embodiment is an example of a roller bearing, it can be similarly applied to a ball bearing incorporating steel balls. Furthermore, in the case of a plastic cage or when the inner surface of the cage pocket hole is made of a non-magnetic material such as brass, it is also possible to take measures such as fitting a metal magnet into the cage pillar that connects the pocket holes.

FIG. 5 is a longitudinal section (axial section) showing another embodiment of the present invention. The cage l of the roller bearing is formed of an annular non-magnetic material, and a magnetized annular magnetic pole plate 5 is attached to the outer surface of one side of the cage with adhesive, rivets, screws, etc., and the magnetization direction of the magnetic pole plate 5 is fixed. so that they face radially from the center of the bearing. In the illustrated example, portions close to the outer ring 3 and the inner ring 2 are magnetized to form N and S poles, respectively. By making the outer diameter side and the inner diameter side of the annular magnetic pole plate 5 have different magnetic poles, the magnetic pole plate 5. Outer ring 3. A magnetic circuit is formed between the roller 4 and the inner ring 2, a strong magnetic field gradient is generated at the contact surface between the raceway surfaces of the inner and outer rings 2 and 3 and the roller 4, and the magnetic fluid flows between the inner and outer rings 2, 3 and the roller 4. is kept concentrated on. Of course, the annular magnetic pole plates 5 may be provided on the outer surface of the cage 1 on both sides of the bearing. Since the magnetic fluid is also held between the inner and outer circumferential surfaces of the cage 1 and the inner and outer rings 2.3 by this magnetic field gradient, a so-called sealing effect is also exhibited, especially when provided on both sides of the bearing. 6 and 7 respectively show modifications of the embodiment shown in FIG. 5, in which the outer edge of the cage 1 has an L-shaped cross-section (FIG. 6) or a U-shaped cross-section (FIG. 7). ) is an example in which a bent annular magnetic pole plate 5 is attached. In the case of FIG. 6, the inner diameter side edge of the magnetic pole plate is bent inward in a convex shape toward the roller 4, and the inner diameter side bent end and the outer diameter side edge are formed into different magnetic poles. , magnetic pole plate5. A magnetic circuit is formed between the outer ring 3 and the roller 4. Although not shown, only the outer diameter side edge may be bent toward the roller. In the latter case, the magnetic pole plate 5. A magnetic circuit is formed between the inner ring 2 and the rollers 4. In addition, as shown in Fig. 7, the edges of both the inner and outer diameter sides are
When the roller 4 is bent inward toward , magnetic lines of force are generated from the bent end along the outer periphery of the roller 4, and a strong magnetic field gradient is also generated at the contact surface between the raceway surfaces of the inner and outer rings and the roller 4.
It becomes possible to hold the magnetic fluid in a concentrated manner.

FIGS. 8 to 11 are diagrams showing other embodiments of the present invention. In both cases, the annular cage itself made of magnetic material is magnetized and its shape is devised so that the magnetic fluid can be effectively retained and concentrated at the required location. First, the example shown in FIG. 8 is an example of a ball bearing, in which the annular cage 1 is magnetized in the direction of the bearing axis, and the edge IC of one side of the cage 10 is brought close to the inner surface of the outer ring 3 at each rolling element portion. The end edge 1d of the other side is brought close to the rolling element 4. As shown in the figure, the magnetic circuit is generated between the cage 1, the outer ring 3, and the rolling elements 4, and the lines of magnetic force cross between the rolling elements 4 and the outer ring raceway.
Since a strong magnetic field gradient is generated during this time, the magnetic fluid can be concentrated and held on the rolling surface. In the example shown in FIG. 9, the above-mentioned configuration is applied to a roller bearing. Similarly, lines of magnetic force run from one edge IC of the cage 1, through the outer ring 3, across the rolling surface, and from the rolling elements 4 to the other edge of the cage. Flows to 1d.

Although FIGS. 8 and 9 show an example in which one end edge IC of the cage 1 is directed toward the outer ring side, an embodiment in which it is directed toward the outer peripheral surface of the inner ring 2 is also possible. Although not shown, the edges of both side surfaces of the cage may be bent toward the rolling wheels. 10 and 11 show an example in which one end edge of the cage 1 is alternately bent toward the inner and outer rings 2°3 in the circumferential direction of the bearing. That is, as best shown in FIG. 11, one end edge I of the cage 1
C is bent alternately at adjacent rolling elements 4 so as to approach the outer ring side and the inner ring side, the other edge 1d is brought closer to the end surface of the rolling element 4, and the cage itself is magnetized in the axial direction of the bearing. do. In addition to this embodiment, one end edge of the cage 1 for each rolling element may be divided into two parts and each part may be bent toward the inner and outer rings. The cage as a whole of the bearing 1. Inner and outer rings 2, 3
Lines of magnetic force flow between the rolling elements 4 and the magnetic fluid concentrates on the transfer surfaces of both the inner and outer rings.

According to the present invention, compared to the conventional structure, the magnetic fluid can be more reliably concentrated and retained in the contact area between the raceway surface in the bearing or the pocket surface of the cage and the rolling elements. You can get the benefits of both grease lubrication and oil lubrication at the same time. That is, the present invention provides the sealing properties that can be obtained with jig grease, and at the same time provides advantages such as ease of use without requiring a special lubrication structure, and difficulty in scattering to the surroundings. In addition, grease is prone to unstable phenomena such as churning, which can cause torque fluctuations in one rotation, but with the bearing of the present invention, such problems do not occur, and noise and vibration caused by unstable phenomena can be suppressed. . Furthermore, it has many advantages such as low torque and high speed rotation due to oil lubrication.

[Brief explanation of the drawing]

Figures 1 (a), (b), and (c) are partial vertical cross-sectional views showing various conventional examples of bearings using magnetic fluid lubrication, and Figure 2 is a portion of a conventional bearing in which magnets are embedded in the rolling elements. 3 is a cross-sectional view of a roller bearing according to an embodiment of the present invention, FIG. 4 is a partial perspective view of the embodiment of FIG. 3 with the outer ring removed, and FIG. The figure is a partial vertical sectional view showing another embodiment of the present invention, FIGS. 6 and 7 are longitudinal sectional views showing a modification of the embodiment of FIG. 5, and FIGS. 8 and 9, respectively. 10 is a partial vertical sectional view showing still another embodiment of the present invention, and FIG. 11 is a partial longitudinal sectional view showing another embodiment of the present invention, and FIG. 11 is a partial longitudinal sectional view showing another embodiment of the present invention. FIG. 1... Cage, 2... Inner ring, 3... Outer ring, 4... Rolling element. Agent Patent attorney Rikichi Someyo (TL or one person) Figure 1 (C) Figure 2 Figure 3 Figure 4 Figure 5 Figure 6F21 Figure 7 Figure 8 Figure 10 Figure 9 Figure 11

Claims (9)

[Claims] (1) A rolling bearing in which a magnetic fluid in which fine magnetic particles are colloidally contained in a non-magnetic oil carrier is sealed as a lubricant, and the magnetic fluid is transferred to the raceway surface of the bearing or the pocket surface of the cage. A rolling bearing characterized by a magnetic field gradient created between the raceway ring or cage and the rolling elements so that the magnetic field is always concentrated at the point of contact with the moving body. (2) The cage is magnetized so that both hole edges in the bearing circumferential direction of each pocket hole of the cage holding the rolling element have different magnetic poles. Rolling bearings listed. (3) The cage holding the rolling element is an annular non-magnetic material, and an annular magnetic pole is magnetized on the annular side surface of the cage so that the inner and outer radial edges have different magnetic poles. A rolling bearing according to claim 1, characterized in that the plate is fixed. (4) The inner or outer edge of the annular magnetic pole plate is bent inward toward the rolling element so that the inner surface of the cage and the bent end of the magnetic pole plate are approximately in the same plane. 4. A roller bearing according to claim 3, characterized in that the rollers are arranged as follows. (5) Both the inner and outer radial edges of the annular magnetic pole plate are bent inward toward the rolling elements so that the inner surface of the cage and both shoulder curved ends of the magnetic pole plate are approximately in the same plane. 4. A roller bearing according to claim 3, characterized in that the rollers are K such that the rollers are curved so that the rollers are curved. (6) The roller according to claim 1, wherein the cage holding the rolling element is an annular magnetic body, and both sides of the cage are magnetized with different magnetic poles. is a bearing. (7) The edge of one side of the annular cage that holds the rolling element is brought close to the inner surface of the outer ring or the outer surface of the inner ring, and the edge of the other side of the cage is moved inward toward the rolling element. 7. The roller bearing according to claim 6, wherein the cage is bent and the edges on both sides of the cage are magnetized to have different magnetic poles. (8) The edge of one side of the circular cage that holds the rolling element is divided into a plurality of pieces in the circumferential direction of the bearing, and these edges are alternately bent toward the outer ring and the inner ring. Claim 6 or 7, characterized in that
Rolling bearings listed in section. (9) The rolling bearing according to claim 6, characterized in that edges of both side surfaces of the annular cage holding the rolling element are bent inward toward the rolling element.