JP2013076468A - Double-row angular ball bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a double-row angular ball bearing, in which the circularity of a bearing ring is excellent.SOLUTION: The double-row angular ball bearing includes an inner ring 1, an outer ring 2, balls 3 in two rows, retainers 4 for retaining the balls 3 in the respective rows between the inner ring 1 and the outer ring 2, and noncontact sealing devices 5 made of a substantially disk-like member. A radially outer end 5a of the sealing device 5 is formed by folding back a radially outermost end of a substantially disk-like member to a radially opposed side, and is fitted and swaged in a groove 2b formed at both axial ends on the inner circumferential surface of the outer ring 2 to be mounted. The diameter of the ball 3 is set to be 75% to 83% of a half a bearing width. A ratio Ts/Tr is equal to or lower than 0.07, where Ts represents the thickness of the sealing device 5 and Tr represents the radial distance between the outer diameter surface of the outer ring 2 and the bottom of the groove 2b. The double-row angular ball bearing can be suitably used for an industrial mechanical pump.

Description

  The present invention relates to a double row angular contact ball bearing.

  A double-row angular contact ball bearing is used as a rolling bearing that rotatably supports the rotary shaft of the submersible pump. The performance required for the pump bearing has a long life, but a high rated load (high load capacity) is required as a bearing performance for realizing the long life. As a means for increasing the load capacity, it is conventionally known to increase the diameter of rolling elements (balls) (see, for example, Patent Document 1).

In addition, sealing performance is also required as a bearing performance for realizing a long life. That is, it is necessary to provide a sealing device for the pump bearing to prevent foreign matter and dust from entering from the outside to the inside and to prevent leakage of the lubricant from the inside to the outside.
As a sealing device, for example, a shield made of a steel plate is known. When the shield is attached to the rolling bearing, for example, the outer end portion in the radial direction of the shield is fitted into a shield groove formed on the inner peripheral surface of the outer ring and then fixed by crimping.

JP 2006-105384 A

However, since a large force is applied to the outer ring during caulking, the outer ring may be deformed and the roundness of the outer diameter surface may deteriorate. In particular, when the radial distance from the bottom of the shield groove to the outer diameter surface of the outer ring (that is, the thickness of the outer ring at the bottom of the shield groove) is small, the roundness is likely to deteriorate due to the low rigidity of the outer ring. . As a result, there is a possibility that the mounting property when mounting the double row angular ball bearing to the housing of the pump is deteriorated or abnormal noise is generated when the double row angular ball bearing rotates.
SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a double-row angular contact ball bearing that solves the above-described problems of the prior art and has an excellent roundness of the race.

  In order to solve the above problems, the present invention has the following configuration. That is, the double-row angular contact ball bearing according to one aspect of the present invention includes an inner ring, an outer ring, and a plurality of rolling elements that are freely rollable between a raceway surface of the inner ring and a raceway surface of the outer ring, A substantially disk-shaped sealing device that is attached to the outer ring and faces the inner ring in a sliding contact or with a gap, and a retainer that holds the rolling element between the inner ring and the outer ring. A double row angular contact ball bearing for an industrial machine pump having a moving body having a diameter of 75% or more and 83% or less of a half of a bearing width, wherein one end portion in the radial direction of the sealing device has the outermost end portion on the opposite side in the radial direction. It is formed by folding back and is attached by caulking to a recess provided in the outer ring, and is arranged radially outward from the outer diameter portion of the cage, and the thickness Ts of the sealing device And between the outer diameter surface of the outer ring and the bottom of the recess The ratio Ts / Tr between the direction distance Tr, characterized in that it is 0.07 or less.

In the double-row angular contact ball bearing, the radial distance between the outer diameter surface and the inner peripheral surface of the outer ring is more than the outer shoulder portion formed on the outer side in the axial direction of the raceway surface. The inner shoulder formed between the two may be larger. Further, the cage may be a crown-shaped cage made of a metal material.
Further, the axial width of one end portion in the radial direction of the sealing device may be 2.7 mm or less. Further, the diameter of the rolling element may be 80% or more and 83% or less of half of the bearing width. Furthermore, the outer diameter of the outer ring may be not less than 50 mm and not more than 140 mm.

  In the double row angular contact ball bearing of the present invention, one end in the radial direction of the sealing device is attached to a recess provided in the outer ring by caulking, and the thickness Ts of the sealing device, the outer diameter surface of the outer ring, the bottom of the recess, Since the ratio Ts / Tr with respect to the radial distance Tr is 0.07 or less, the thickness of the outer ring at the bottom of the recess is large. Therefore, since the rigidity of the outer ring is high, the roundness of the outer ring is hardly deteriorated during caulking, and the double-row angular contact ball bearing of the present invention has an excellent roundness of the outer ring.

It is a fragmentary longitudinal cross-section which shows one Embodiment of the double row angular contact ball bearing which concerns on this invention. It is the elements on larger scale of the sealing device integrated in the double row angular contact ball bearing of Drawing 1, and its peripheral part. It is a figure which shows the result of having measured the roundness of the outer ring | wheel of the bearing of an Example. It is a figure which shows the result of having measured the roundness of the outer ring | wheel of the bearing of a comparative example. It is a figure which shows the result of having measured the roundness of the outer ring | wheel of the bearing of a reference example.

  An embodiment of a double-row angular contact ball bearing according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a partial longitudinal sectional view showing an embodiment of a double-row angular contact ball bearing according to the present invention. 2 is a partially enlarged cross-sectional view of the sealing device incorporated in the double row angular contact ball bearing of FIG. 1 and its peripheral portion.

  The double-row angular contact ball bearing shown in FIG. 1 has two rows of balls which are arranged to roll freely between an inner ring 1, an outer ring 2, and raceway surfaces 1 a and 1 a of the inner ring 1 and raceway surfaces 2 a and 2 a of the outer ring 2. 3, retainers 4, 4 for holding the balls 3 in each row between the inner ring 1 and the outer ring 2, and non-contact type sealing devices 5, 5 made of a substantially disk-shaped member. . And in the space | gap part (bearing internal space) enclosed with the inner ring | wheel 1, the outer ring | wheel 2, and the sealing devices 5 and 5, lubrication with both the raceway surfaces 1a and 2a and the rolling surface 3a of the rolling element 3 is shown. Do not use lubricants (for example, lubricating oil and grease). The sealing device 5 may be a contact-type sealing device that is in sliding contact with the raceway ring (inner ring 1 in the case of FIG. 1). Further, the cage 4 may not be provided.

  The inner ring 1, the outer ring 2, and the ball 3 are made of a steel material (for example, stainless steel or bearing steel) that is generally employed as a material for a bearing ring or rolling element of a rolling bearing. The cage 4 is made of a resin material (for example, polyamide, polyphenylene sulfide) or a metal material (for example, steel, brass, aluminum alloy) generally adopted as a material for the cage of the rolling bearing.

Furthermore, the sealing device 5 is made of a metal material such as steel (an example of such a sealing device is a steel plate shield), and its radially outer end 5a is the inner periphery of the outer ring 2. Attached to both axial ends of the surface. More specifically, the outer circumferential end 5a of the sealing device 5 is fitted into the grooves 2b (concave portions) formed at both axial ends of the inner peripheral surface of the outer ring 2 by being fitted and crimped.
The radially outer end portion 5a of the sealing device 5 is formed by folding back the radially outermost end portion of the substantially disk-shaped member to the radially opposite side (that is, the radially inner end side), and has a substantially U-shaped cross section. A radially outer end 5a having a substantially U-shaped cross section is fitted into the groove 2b and crimped.

At this time, the thickness Ts of the substantially disk-shaped member constituting the sealing device 5 is thinner and the thickness of the outer ring 2 at the bottom of the groove 2b as compared with a conventional double row angular contact ball bearing of the same size. (That is, the radial distance between the outer diameter surface of the outer ring 2 and the bottom of the groove 2b) Tr is large. Furthermore, the ratio Ts / Tr between the thickness Ts of the sealing device 5 and the thickness Tr of the outer ring 2 at the bottom of the groove 2b is 0.07 or less. The axial width Tc of the radially outer end 5a having a substantially U-shaped cross section is set to 2.7 mm or less.
The radially inner end 5b of the sealing device 5 is opposed to the outer peripheral surface of the inner ring 1 with a gap (labyrinth gap). A facing surface 1b, which is a portion facing the radially inner end portion 5b, of the outer peripheral surface of the inner ring 1 forms a labyrinth by facing the radially inner end portion 5b with a gap.

  As described above, the double-row angular contact ball bearing of the present embodiment is thinner than the conventional double-row angular contact ball bearing of the same size because the thickness Ts of the substantially disk-shaped member constituting the sealing device 5 is thin. The thickness of the outer ring 2 at the bottom of 2b can be increased. As a result, since the rigidity of the outer ring 2 is increased, the outer ring 2 is not easily deformed when the sealing device 5 is caulked. If the thickness ratio Ts / Tr exceeds 0.07, the rigidity of the outer ring 2 becomes insufficient, and the outer ring 2 may be deformed when the sealing device 5 is caulked.

  Furthermore, since the axial width Tc of the radially outer end 5a having a substantially U-shaped cross section is small, the force required for caulking the sealing device 5 is small. As a result, the force applied to the outer ring 2 when the sealing device 5 is caulked is reduced, so that the outer ring 2 is not easily deformed when caulking. If the axial width Tc of the radially outer end 5a exceeds 2.7 mm, the force required for caulking of the sealing device 5 increases, and therefore the force applied to the outer ring 2 when the sealing device 5 is caulked and mounted. There is a risk that the outer ring 2 will be deformed.

As described above, the double row angular contact ball bearing of this embodiment is excellent in the roundness of the outer diameter surface of the outer ring 2 because the outer ring 2 is not easily deformed when the sealing device 5 is caulked. Therefore, the double-row angular contact ball bearing of the present embodiment has excellent mountability when mounted on a housing such as a pump and is unlikely to generate abnormal noise during rotation.
In addition, the diameter of the ball in the conventional double-row angular contact ball bearing is usually 68% or more and 71% or less of half of the bearing width, but in the double-row angular contact ball bearing of this embodiment, the diameter of the ball 3 is The diameter is set to 75% or more and 83% or less of half of the bearing width of the double row angular contact ball bearing.

  If the diameter of the ball 3 is increased and the ratio of the diameter of the ball 3 to the bearing width is increased, the double-row angular contact ball bearing has a high load capacity and a long life. If the diameter of the ball 3 is less than 75% of half of the bearing width, the load capacity of the double row angular ball bearing may not be sufficiently improved. On the other hand, if it exceeds 83%, the axial clearance between the sealing device 5 and the retainer 4 (or the ball 3) cannot be sufficiently ensured and there is a risk of interference. In order to make such inconvenience less likely to occur, it is more preferable to set the diameter of the ball 3 to 80% or more and 83% or less of half of the bearing width.

  The outer ring 2 corresponds to “one race ring (a race ring to which a sealing device is attached)” which is a constituent requirement of the present invention, and the inner ring 1 corresponds to “the other race ring (sealing device) which is a constituent requirement of the present invention. Corresponds to the raceway facing each other with a sliding contact or a gap. Of course, the radially inner end 5b of the sealing device 5 may be attached to the inner ring 1 and the radially outer end 5a may be opposed to the inner peripheral surface of the outer ring 2 with a gap. Further, the sealing device 5 may be attached only to one end portion in the axial direction of the inner peripheral surface of the outer ring 2.

  Moreover, since the thickness Ts of the substantially disc-shaped member which comprises the sealing device 5 is thin, the double row angular contact ball bearing of this embodiment is the axial direction between the sealing device 5 and the holder | retainer 4 (or ball | bowl 3). Sufficient clearance is easily secured. Therefore, even if the ball 3 has a large diameter, the sealing device 5 and the retainer 4 (or the ball 3) are unlikely to interfere with each other. Therefore, the double-row angular contact ball bearing of the present embodiment is based on an increase in the diameter of the ball 3. Easy to apply high load capacity.

  Furthermore, if the axial clearance between the sealing device 5 and the cage 4 (or ball 3) is sufficiently secured, the sealing device 5 and the cage 4 (or ball 3) even if the ball 3 has a large diameter. The double-row angular contact ball bearing of this embodiment has excellent sealing performance (that is, foreign matter and dust intrude from the outside to the inside of the bearing, and leakage of lubricant from the inside to the outside). Is less likely to occur). Further, since the sealing device 5 and the cage 4 (or the ball 3) do not easily interfere with each other, the sealing device 5 falls off, the lubricant leaks, the noise from the double row angular ball bearing, the abnormal wear of the double row angular ball bearing Is unlikely to occur.

Furthermore, since the double row angular contact ball bearing of this embodiment is a high load type bearing, it is preferable that the outer diameter of the outer ring 2 be 50 mm or more and 140 mm or less.
Because of the excellent characteristics as described above, the double-row angular contact ball bearing of the present embodiment can be suitably used as a rolling bearing that rotatably supports a rotary shaft of a pump such as a submersible pump.

  Industrial machine pumps such as submersible pumps are strongly required mainly to save space (compactness) and reduce maintenance costs. For this reason, pump manufacturers are aiming to increase the capacity of pumps (improving the amount of liquid delivered), to reduce the size and weight, to improve efficiency, and to improve reliability. In particular, rolling bearings that do not require lubrication are required for applications that cannot be easily maintained, such as submersible pumps.

  Since the double-row angular contact ball bearing of this embodiment has a high load capacity and a long life as described above, it can be suitably used for an industrial machine pump. In particular, since the submersible pump is used in a state where the rotation shaft of the motor is vertical, the double-row angular contact ball bearing of the present embodiment can be suitably used as a bearing that rotatably supports the rotation shaft. In addition, since the double row angular contact ball bearing of this embodiment has excellent sealing performance as described above, foreign matter and dust intrude from the outside to the inside of the bearing and leakage of lubricant from the inside to the outside occurs. Hateful. Therefore, since almost no maintenance such as lubrication is required, it can be suitably used for industrial machine pumps such as submersible pumps.

In addition, this embodiment shows an example of this invention and this invention is not limited to this embodiment. For example, in the present embodiment, the example of the sealing device 5 made entirely of metal has been described, but the radially outer end 5a attached to the outer ring 2 may be substantially plate-shaped and made of a metal material. The other portions such as the radially inner end portion 5b may have a shape other than a substantially plate shape, or may be made of a polymer material such as rubber or plastic.
In the present embodiment, the example in which the rolling bearing is a double-row angular contact ball bearing has been described. However, the present invention is applicable to other types of rolling bearings, such as a single-row angular contact ball bearing. It can be applied to deep groove ball bearings, self-aligning ball bearings, cylindrical roller bearings, tapered roller bearings, needle roller bearings, and self-aligning roller bearings.

  Next, an Example is shown and this invention is demonstrated further more concretely. The double-row angular contact shown in FIGS. 1 and 2 is attached to the outer ring by inserting the radial outer ends of the steel plate shields into the grooves formed at both axial ends of the inner peripheral surface of the outer ring and crimping. A double-row angular contact ball bearing having the same configuration as the ball bearing was manufactured. The radially outer end of the shield has a substantially U-shaped cross section as described above.

  In the double-row angular contact ball bearing of the example, the shield thickness Ts is 0.23 mm, the outer ring thickness Tr at the bottom of the groove is 4 mm, and the ratio Ts / Tr of both thicknesses is 0.058. is there. On the other hand, the double row angular contact ball bearing of the comparative example has a shield thickness Ts of 0.3 mm, an outer ring thickness Tr at the bottom of the groove of 3.3 mm, and a ratio Ts / Tr of both thicknesses. 0.09. Further, the double-row angular contact ball bearings of the two reference examples are those in which no shield is attached to each of the example and the comparative example.

The roundness of the outer diameter surface of the outer ring of these four double-row angular contact ball bearings was measured. FIG. 3 shows the measurement result of the roundness of the example, FIG. 4 shows the measurement result of the roundness of the comparative example, and FIG. 5 shows the measurement result of the roundness of the reference example. Since the roundness of the two reference examples is almost the same, only one of them is shown in FIG.
When shown by relative values when the roundness of the reference example is 1, the roundness of the example was 1.8 and the roundness of the comparative example was 5.3. From these results, in the example and the comparative example with the shield attached, the roundness of the outer surface of the outer ring is larger in the double row angular contact ball bearing of the example than in the double row angular contact ball bearing of the comparative example. Can be seen to be significantly better.

DESCRIPTION OF SYMBOLS 1 Inner ring 1a Raceway surface 2 Outer ring 2a Raceway surface 2b Groove 3 Rolling body 3a Rolling surface 4 Cage 5 Sealing device 5a Radial outer end portion 5b Radial inner end portion Ts Thickness of the substantially disk-shaped member constituting the sealing device Tr Thickness of outer ring at bottom of groove Tc Axial width of radially outer end of substantially U-shaped cross section

Claims (6)

An inner ring, an outer ring, a plurality of rolling elements arranged in a freely rolling manner between the raceway surface of the inner ring and the raceway surface of the outer ring, and facing the inner ring with a sliding contact or a gap attached to the outer ring And a retainer for holding the rolling element between the inner ring and the outer ring, and the diameter of the rolling element is 75% or more and 83% or less of half of the bearing width. A double row angular contact ball bearing for an industrial machine pump,
One end portion in the radial direction of the sealing device is formed by folding back the outermost end portion to the opposite side in the radial direction, and is attached to the concave portion provided in the outer ring by caulking, and the outer diameter portion of the cage Is arranged radially outward,
A ratio Ts / Tr between the thickness Ts of the sealing device and the radial distance Tr between the outer diameter surface of the outer ring and the bottom portion of the recess is 0.07 or less. Ball bearing.   The radial distance between the outer diameter surface and the inner peripheral surface of the outer ring is an inner shoulder portion formed between the raceway surfaces in a double row rather than an outer shoulder portion formed on the outer side in the axial direction of the raceway surface. The double row angular contact ball bearing according to claim 1, wherein is larger.   The double-row angular contact ball bearing according to claim 1 or 2, wherein the cage is a crown-shaped cage made of a metal material.   The double-row angular contact ball bearing according to any one of claims 1 to 3, wherein an axial width of one end portion in a radial direction of the sealing device is 2.7 mm or less.   The double row angular contact ball bearing according to any one of claims 1 to 4, wherein a diameter of the rolling element is 80% or more and 83% or less of a half of a bearing width.   The double-row angular contact ball bearing according to any one of claims 1 to 5, wherein an outer diameter of the outer ring is 50 mm or more and 140 mm or less.

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