JP2014092164A - Tandem type double row angular ball bearing with seal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an impression from occurring on the surface of a ball, on the raceway surfaces of an inner ring and an outer ring or on both surfaces by putting a foreign matter, such as abrasion powder of a gear, into a contact part between the ball and the inner ring and a contact part between the ball and the outer ring.SOLUTION: In a tandem type angular ball bearing, a seal 20 is attached to at least one of both end opening parts in an axial direction formed by an outer ring inner periphery and an inner ring outer periphery. Preferably, seal lips 22, 32 serving as the contacts parts of a contact seal are brought into contact with end surface sides 40, 50 of the inner ring serving as a rotation ring.

Description

The present invention relates to a tandem double-row angular contact ball bearing with a seal.

Conventionally, tapered roller bearings have been used to rotationally support a pinion shaft and a transmission of an automobile differential device.

However, although the tapered roller bearing has an advantage that it can support a relatively large radial load and a relatively large axial load at the same time, the head portion is in a sliding contact state at a large collar portion, and rotational torque and starting torque are not generated. May be relatively large.

An increase in rotational torque or the like is likely to lead to a deterioration in the fuel consumption of the automobile, and so improvement has been demanded.

Therefore, tandem type double-row angular ball bearings as shown in FIG. 1 have been increasingly used mainly for the purpose of reducing rotational torque. In the tandem type angular contact ball bearing, a sliding part that increases torque such as a roller head and a collar part of a tapered roller bearing substantially exists between the balls 3 and 4 and the resin cages 5 and 6. Therefore, the rotational torque is low.

JP 2011-210984 A

However, the bearing that supports the pinion shaft is lubricated by gear oil that is also used for lubrication of the pinion gear portion. In other words, the bearing is generally lubricated by the lubricating oil that lubricates the pinion gear portion.

Therefore, the bearings are often lubricated with lubricating oil that easily contains foreign matters such as gear wear powder.

Under such a condition, when a tandem angular ball bearing is used, foreign matter such as gear wear powder enters the contact portions 10, 11, 12, 13 between the balls 3, 4 and the inner ring 4, the outer ring 5, and the balls 3, Indentation is made on the surface of 4, the raceway surface of the inner ring 4, the outer ring 5, or both.

In the case of a tapered roller bearing, for example, since the contact pressure between the tapered roller and the raceway surface when the same load is supported is relatively low, indentation hardly occurs. However, in the case of a tandem angular contact ball bearing, Since the contact surface pressure between the balls 3 and 4 that are rolling elements in 11, 12, and 13 and the raceway surface is relatively high, indentations are likely to occur.

The generation of indentations is not so much affected when the number and size of the indentations is relatively small and small, but when the number and size are large, there is a possibility of leading to defects such as separation of the raceway surface.

In order to solve the above-described problems, the tandem angular contact ball bearing of the present invention has a seal attached to at least one of both axial opening portions formed on the inner periphery of the outer ring and the outer periphery of the inner ring.

In other words, the bearing opening is closed with a predetermined seal, so that only a necessary amount of lubricating oil is introduced into the bearing, and foreign matter such as gear wear powder is prevented from entering by the seal.

Preferably, the seal is attached to the open end of the smaller row of ball PCDs. That is, the lubricating oil adhering to the inner ring outer diameter portion of the small row of ball PCDs moves to enter the inside of the bearing due to the centrifugal force due to the rotation of the bearing. Therefore, the flow of the lubricating oil inside the bearing is a flow from a small row of ball PCDs to a large row of ball PCDs. Similarly, due to the action of centrifugal force, the open end of the smaller row of ball PCDs may act to suck in lubricating oil. Therefore, in order to prevent the entry of foreign matter while introducing a necessary amount of lubricating oil, it is preferable to provide a seal at this portion.

Preferably, both the axial end openings of the bearing are sealed. Thereby, the invasion of foreign matters can be further prevented.

Preferably, the seal is a contact seal. By using a contact seal, the effect of preventing entry of foreign matter is improved.

Preferably, the tip of the seal lip, which is the contact portion of the contact seal, has an acute angle. By using an acute angle, the sliding resistance of the seal lip can be lowered, and the rotational torque can be further reduced while preventing entry of foreign matter.

Preferably, a seal lip which is a contact portion of the contact seal is brought into contact with the end face side of the inner ring which is a rotating ring. In this way, by using a so-called end surface contact seal, the radius of the portion where the seal lip is slidably contacted can be made relatively small, so the seal lip portion can be contacted at a portion where the peripheral speed is slow, and thus more stable. Intrusion of foreign matter can be prevented.

More preferably, the bearing opening side of the smaller ball PCD is an end face contact seal. As described above, the smaller opening of the ball PCD tends to suck the lubricating oil by centrifugal force, and since the lubricating oil is controlled by a portion having a smaller centrifugal force, the effect of preventing the entry of foreign matter is It will be even better.

According to the sealed tandem double-row angular contact ball bearing of the present invention, it is possible to effectively prevent foreign matter from entering the bearing.

It is a figure explaining the conventional tandem type double row angular contact ball bearing. It is a figure explaining an example of the tandem type double row angular contact ball bearing of the present invention. It is a figure explaining an example of the tandem type double row angular contact ball bearing of the present invention. It is a figure explaining an example of the tandem type double row angular contact ball bearing of the present invention. It is a figure explaining an example of the tandem type double row angular contact ball bearing of the present invention.

FIG. 2 shows an example of a sealed tandem double-row angular contact ball bearing of the present invention. The basic structure is the same as that of the bearing shown in FIG. The contact angles θ1 and θ2 may be the same or different from each other, and are generally in the range of 10 to 60 degrees.

In the example shown in FIG. 2, seal mounting grooves 25 and 35 are provided in the outer ring, and the seals 20 and 30 are mounted on the outer ring that is a stationary ring. The seals 20 and 30 are rubber seals made up of core bars 21 and 31 and rubber portions forming seal lips 22 and 32, respectively.

In the example shown in FIG. 2, the seal 20 on the inner ring end face 40 side of the smaller row of ball PCDs has an end face seal configuration in which the seal lip 22 is brought into contact with the end face 40 of the inner ring. The other bearing opening has a seal configuration in which the seal lip 32 is brought into contact with the outer periphery 50 of the inner ring.

The tip part which is the contact part of the seal lips 22 and 32 has an acute angle as shown in FIG.

Further, since the inner ring outer periphery 50 of the larger ball PCD and the seal lip 32 are in contact with each other in the radial direction, excess lubricating oil is easily discharged, and the rotational torque increases due to contact with the inner ring outer periphery 50 of the seal lip 32. There are few things.

In the example shown in FIG. 3A, the seal 20 is attached only to the inner ring end face 40 side of the smaller row of ball PCDs. The seal 20 has an end face seal configuration in which the seal lip 22 is brought into contact with the end face 40 of the inner ring.

The example shown in FIG. 2 is also the same, but as shown in an enlarged view of FIG. 3 (b), the contact portion of the seal lip 22 is preferably arranged outside the half of the radial thickness of the inner ring end face 40. . Thereby, the contact surface for the inner ring | wheel end surface 40 to abut against other components is securable.

The example shown in FIG. 2 is the same, but as shown in an enlarged view in FIG. 3B, preferably, a labyrinth seal lip 24 is provided, and between the labyrinth seal lip 24 and the inner ring end surface 41, It is preferable to provide an axial labyrinth gap. Thereby, the flow of the lubricating oil that has entered the inside of the bearing can be controlled more appropriately.

Furthermore, the gap between the labyrinth seal lip and the end face 7 of the cage 5 is reduced so that it does not come into contact with the bearing when it is used, so that the labyrinth can be used to control the flow of lubricating oil more appropriately. it can.

In the example shown in FIG. 4, the seal in the larger row of ball PCDs is a non-contact type rubber seal 36. The lip portion of the rubber seal 36 is opposed to the outer peripheral surface 50 of the inner ring 2 but forms an axial labyrinth gap.

Even on the outflow side of the lubricating oil, the flow of the lubricating oil as a whole of the bearing can be more appropriately controlled by controlling the degree of outflow with a so-called labyrinth seal. In addition, even when the flow of lubricating oil is low, the flow of lubricating oil is reversed for some reason, or when the rotation of the bearing stops, it is possible to effectively prevent foreign matter from entering the bearing. be able to. Further, since it is a non-contact type seal, the rotational torque of the bearing is not increased.

In the form shown in FIG. 5, a non-contact shield 37 made of metal or resin is attached to the larger row of ball PCDs. By using the non-contact shield 37 made of metal or resin, the effect can be obtained at a lower cost. Also in this case, it is preferable to form an axial labyrinth gap between the tip of the non-contact shield 37 and the outer peripheral surface 50 of the inner ring 2.

The present invention can be suitably used for an automobile differential device, a transmission, and the like.

1 Outer ring 2 Inner ring

Claims (1)

The tandem angular contact ball bearing is characterized in that a seal is attached to at least one of both end portions in the axial direction formed by the inner periphery of the outer ring and the outer periphery of the inner ring.

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