JP6446852B2 - Rolling bearing device - Google Patents

Description

  The present invention relates to a rolling bearing device using a sealing device, and more particularly to a rolling bearing device used in inner ring rotation.

  Conventionally, in rolling bearing devices, a contact type or non-contact type sealing device is provided to prevent leakage of lubricant such as grease enclosed in the bearing internal space and to prevent water and foreign matter from entering from the outside. ing. For example, a non-contact type sealing device is known in which a seal member is attached to both end openings of an outer ring member and a labyrinth is formed between the outer ring portion of the inner ring member.

By the way, this type of sealing device is a rolling bearing device that requires high sealing performance, particularly a rolling bearing device used in a vacuum environment, and a rolling bearing device used for a spindle of a machine tool that rotates at high speed. There is a problem that the intended function cannot be fully exhibited.
As a measure for improving the above problems, as shown in Patent Document 1, as means for generating an air flow in the axial direction of the rolling bearing device in the outer peripheral portion of the inner ring member forming the labyrinth, It is conceivable to provide a spiral groove twisted with respect to the axis of the bearing device.

JP 2009-92127 A

  In order to suppress the leakage of the lubricant inside the bearing of the rolling bearing device to the outside and the entry of water and foreign matter from the outside, it is effective to make the gap of the labyrinth as small as possible. However, in the rolling bearing device of Patent Document 1 described above, the labyrinth is formed between the seal member attached to the outer ring member and the outer peripheral portion of the inner ring member, so that a processing error of the seal member affects, It is extremely difficult to reduce the labyrinth gap.

  Therefore, it cannot be said that it is sufficient to suppress the leakage of the lubricant inside the bearing to the outside and the entry of water and foreign matter from the outside.

  It is an object of the present invention to provide a rolling bearing device that can prevent foreign matter from entering the bearing internal space and leakage of the lubricant to the outside, and prevent a bearing portion from being defective due to poor lubrication.

In order to solve the above problems, the structural features of the invention according to claim 1 are: an outer ring member having an outer ring raceway formed on the inner periphery; an inner ring member having an inner ring raceway formed on the outer periphery; and the outer ring track A plurality of rolling elements that roll between the inner ring raceways, a lubricant is sealed in a bearing inner space between the inner circumference of the outer ring member and the outer circumference of the inner ring member, A rolling bearing device that rotates in a direction, a cylindrical sealed outer peripheral surface parallel to an axis formed on an outer side of the axial ring bearing from the inner ring raceway on the outer periphery of the inner ring member, and the inner periphery of the outer ring member A cylindrical sealed inner peripheral surface parallel to the axis formed on the outer side of the bearing in the axial direction from the outer ring raceway is opposed to each other in the radial direction to form a labyrinth-shaped gap that seals the bearing inner space, is formed on the sealing outer peripheral surface, the bearing inner space side Generating a flow of air to Luo outward, it has a spiral groove twisted with respect to the axis of the rolling bearing device, toward the gap of the labyrinth by opening the sealed peripheral surface of the outer ring member An air inflow hole is formed from the labyrinth-shaped gap to the clean outer space, and the sealed inner peripheral surface includes an opening to the labyrinth-shaped gap of the air inflow hole and is orthogonal to the axis. That is, an air groove that is recessed radially outward in the direction is formed over the entire circumference .

  According to the configuration of the present invention, the sealed inner peripheral surface of the outer ring member that forms the labyrinth-shaped gap (hereinafter referred to as labyrinth) that seals the bearing internal space, and the sealed outer peripheral surface of the inner ring member, The outer ring raceway and the inner ring raceway are formed with the same accuracy. That is, the dimensional variation and runout of the sealed inner peripheral surface of the outer ring member and the sealed outer peripheral surface of the inner ring member are smaller than those of a rolling bearing device using a normal labyrinth component member.

As a result, it is possible to avoid contact due to dimensional variation, runout, etc. between the sealed inner peripheral surface of the outer ring member and the sealed outer peripheral surface of the inner ring member, which form the labyrinth, and even if the gap between the labyrinths is extremely small The sealed inner peripheral surface of the outer ring member does not come into contact with the sealed outer peripheral surface of the inner ring member.
That is, the labyrinth interval of the rolling bearing device of the present invention is much smaller than that of a normal rolling bearing device using a member for labyrinth configuration, and has a high sealing performance as compared with a normal rolling bearing device. ing.

  The inner ring member, which is a rotating member, has a spiral groove twisted with respect to the axis on the sealed outer peripheral surface forming a labyrinth, and the inner ring member rotates in one direction, so that the bearing An air flow from the internal space (hereinafter referred to as internal space) side to the outside is generated. This air flow can suppress moisture and foreign matter from entering the labyrinth from the outside. In addition, air flowing from the sealed inner peripheral surface forming the labyrinth of the outer ring member to the clean outer space in a clean environment is formed, so that air flowing outward is supplied from the air inflow hole. Thus, leakage of the lubricant in the internal space to the outside is suppressed.

  Furthermore, according to one aspect of the present invention, an air groove that includes an opening to the labyrinth-shaped gap of the air inflow hole on the sealed inner peripheral surface, and an air groove that is recessed radially outward in a direction perpendicular to the axis is the entire circumference. Is formed over.

  According to this configuration, the air flowing in from the air inflow hole is supplied to the entire circumference by the air groove formed over the entire circumference, and moves outward from all the spiral grooves formed in the sealed outer circumferential surface. . For this reason, the amount of air flowing from the internal space side to the outside increases, and it is possible to further suppress the intrusion of moisture and foreign matter into the labyrinth.

  In order to solve the above-mentioned problem, the structural feature of the invention according to claim 2 is that the spiral groove is formed on the outside of the labyrinth-shaped gap in the axial direction from the air inflow hole. is there.

  According to the configuration of the present invention, the air flow from the axially inner side to the outer side of the rolling bearing is generated on the outer side from the air inflow hole, and the air supplied from the air inflow hole flows out to the outside. Air and lubricant in the internal space are sealed by the labyrinth on the internal space side from the air inflow hole, and leakage of the lubricant in the internal space to the outside is further suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, the rolling bearing apparatus which can suppress the penetration | invasion of the foreign material to the inside of a bearing and the leakage to the exterior of a lubricant, and can prevent the malfunction as a bearing by lubrication failure can be provided.

It is a partial cross section figure of the rolling bearing apparatus of embodiment of this invention. It is an enlarged view of the principal part of the rolling bearing apparatus of embodiment of this invention.

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

FIG. 1 is a cross-sectional view of a rolling bearing device according to an embodiment of the present invention.
FIG. 2 is an enlarged view of the main part of FIG.

  1 and 2, the rolling bearing device 1 includes an outer ring member 20 having an outer ring raceway 21 formed on the inner periphery, an inner ring member 30 having an outer ring raceway 31 formed on the outer periphery, the outer ring raceway 21 and the inner ring member. It has balls 40 as a plurality of rolling elements that are arranged between the 30 inner ring raceways 31 so as to be freely rollable, and a cage 50 that holds the balls 40.

  The outer ring member 20 is an annulus made of a steel material such as bearing steel, and an outer ring raceway 21 is formed at an axially intermediate portion of the inner peripheral portion. A cylindrical hole-shaped outer ring shoulder surface 23 is formed from the small-diameter end of the outer ring raceway 21 in the axial direction opposite to the external direction, and an outer ring counter surface 24 is formed from the large-diameter end of the outer ring raceway 21 in the axial direction outward direction. ing. From the outer end of the outer ring counter surface 24 in the axial direction outer side, a diameter of the outer ring counter surface 24 is increased and a cylindrical inner peripheral surface 25 having a cylindrical hole shape is formed in the outer direction of the axial direction. The sealed inner peripheral surface 25 is ground with the same grindstone as the outer ring raceway 21 at the same time as the outer ring raceway 21, is substantially concentric with the outer ring raceway 21, and has the same accuracy as the outer ring raceway 21. .

  In addition, a plurality of air inflow holes 28 are formed which penetrate from the sealed inner peripheral surface 25 to the outer ring outer peripheral surface 22 in the radial direction and communicate with the outer space 8 which is a clean outer space. The sealed inner peripheral surface 25 includes an opening of the air inflow hole 28, and is formed with a circumferential air groove 29 that is orthogonal to the axis and is recessed radially outward. The sealed inner peripheral surface 25 has an inner sealed inner peripheral surface 26 on the inner space side from the air groove 29 and an outer sealed inner peripheral surface 27 on the outer side from the air groove 29.

  The inner ring member 30 is an annular body made of a steel material such as bearing steel, and an inner ring raceway 31 having a circular arc shape in cross section is formed at an axially intermediate portion of the outer peripheral portion. An inner ring counter surface 32 is formed in the axial direction anti-external direction from the small-diameter side end of the inner ring raceway 31, and an inner ring shoulder surface 33 is formed in the axial direction external direction from the large-diameter end of the inner ring raceway 31. From the outer end of the inner ring shoulder surface 33 in the axial direction, a diameter of the inner ring shoulder surface 33 is increased, and a sealed outer peripheral surface 34 having a cylindrical hole shape is formed outward in the axial direction.

  The sealed outer peripheral surface 34 is ground with the same grindstone as the inner ring raceway 31 at the same time as the inner ring raceway 31, is substantially concentric with the inner ring raceway 31, and has substantially the same accuracy as the inner ring raceway 31. Further, the diameter of the sealed outer peripheral surface 34 is formed slightly smaller than the diameter of the sealed inner peripheral surface 25 of the outer ring member 20.

  In the sealed outer circumferential surface 34, the inner ring raceway 31 side in the axial direction is a cylindrical inner sealed outer circumferential surface 35 having no grooves, and the outer side in the axial direction sandwiches a circumferential relief groove 37 recessed radially inward. Thus, the outer sealing outer peripheral surface 36 is formed with a plurality of spiral grooves 38 that are recessed inward in the radial direction. The escape groove 37 is formed in the same position as the air inflow hole 28 and the air groove 29 of the outer ring member 20 in the axial direction. The spiral groove 38 is formed to be inclined toward the inner ring raceway 31 with respect to the rotation direction (arrow direction in FIG. 2) of the sealing outer peripheral surface 34.

  The cage 50 is made of a resin such as reinforced polyamide, and is formed into a ring by injection molding or the like. At one end in the axial direction, an annular part 51 and a plurality of column parts 52 projecting in the axial direction from the annular part 51 are provided. A plurality of pockets 53 that hold the plurality of balls 4 by the annular portion 51 and the column portion 52 are partitioned and formed on the circumference equally.

The ball 40 is a sphere made of a steel material such as bearing steel. The plurality of balls 40 are respectively held in a plurality of pockets 53 of the cage 50, and are arranged in contact with the outer ring raceway 21 and the inner ring raceway 31 so as to roll freely.
An inner space 70 is interposed between the periphery of the outer ring raceway 21 in the inner peripheral portion of the outer ring member 20 and the periphery of the inner ring raceway 31 in the inner peripheral portion of the inner ring member 30, and oil as a lubricant is contained in the inner space 70. 80 is enclosed.

In this state, the sealed inner peripheral surface 25 and the sealed outer peripheral surface 34 face each other to form a labyrinth 60 as a labyrinth-like gap.
The labyrinth 60 includes an inner labyrinth 61 that faces the inner sealed inner peripheral surface 26 and the inner sealed outer peripheral surface 35 on the axial inner ring raceway 31 side, that is, the inner space 70 side, and an outer sealed inner peripheral surface 27. The outer labyrinth 62 is opposed to the outer sealing outer peripheral surface 36.

  Hereinafter, based on FIG. 1, FIG. 2, the effect | action of the rolling bearing apparatus 1 of embodiment is demonstrated. In the rolling bearing device 1, the rotating shaft 2 is fitted into the inner ring member 30, and the outer ring outer peripheral surface 22 of the outer ring member 20 is accommodated in the housing, so that the rotating shaft 2 is rotatably supported. That is, the inner ring member 30 rotates in one direction, that is, in the direction of the arrow in the figure, and the outer ring member 20 is fixed. The internal space 70 is sealed by a labyrinth 60 to prevent entry of foreign matter from the outside and leakage of the oil 80.

  Here, the diameter of the sealing outer peripheral surface 34 constituting the labyrinth 60 is slightly smaller than the diameter of the sealing inner peripheral surface 25. For this reason, the labyrinth 60 is much smaller than a normal rolling bearing device using a member for constituting a labyrinth, and has a high sealing performance as compared with a normal rolling bearing device.

  Further, by the rotation of the inner ring 3 in the direction of the arrow in the figure, the spiral groove 38 formed in the outer sealed outer peripheral surface 36 constituting the outer labyrinth 62 rotates in the direction of the arrow in FIG. Moves relatively in the counter-rotating direction along the side surface of the spiral groove 38. Here, the spiral groove 38 is formed to be inclined toward the inner ring raceway 31 with respect to the rotation direction, and is shown in FIG. 2 in the air relatively moving in the counter-rotation direction along the side surface of the spiral groove 38. A flow toward the outside direction indicated by the white arrow is generated.

That is, the air in the outer labyrinth 62 moves outward. Further, the air flowing from the clean outer space 8 through the plurality of air inflow holes 28 of the outer ring member 20 into the annular air groove 29 is supplied to the plurality of spiral grooves 38 evenly. The air flow toward the outside continues.

  By the above-described air flow, moisture and foreign matter can be further prevented from entering the labyrinth 60 from the outside 9, and air is continuously supplied from the air inflow hole 28, so Leakage to the outside of the oil 80 in the space 70 is suppressed.

  As described above, the rolling bearing device 1 according to the embodiment of the present invention suppresses intrusion of foreign matter into the internal space 70 and leakage of the oil 80 to the outside, and can prevent problems as a bearing due to poor lubrication. Can be provided.

  In the rolling bearing device 1 of the above-described embodiment, the sealed inner peripheral surface 25 of the outer ring member 20 is formed with a diameter expanded from the outer ring raceway 21, and the sealed outer peripheral surface 34 of the inner ring member 30 is formed with a diameter expanded from the inner ring raceway 31. Has been. However, in the present invention, for example, the sealed inner peripheral surface 25 of the outer ring member 20 is formed with a reduced diameter from the outer ring raceway 21, and the sealed outer peripheral surface 34 of the inner ring member 30 is formed with a reduced diameter from the inner ring raceway 31. The sealing inner peripheral surface 25 and the sealing outer peripheral surface 34 may be formed at different positions from the rolling bearing device 1 of the above-described embodiment.

  In the rolling bearing device 1 of the above-described embodiment, the air groove 29 is formed on the sealed inner peripheral surface 25 of the outer ring member 20, but in the present invention, the air groove 29 is formed on the sealed inner peripheral surface 25 of the outer ring member 20. It may be a rolling bearing device having a configuration that is not provided.

  In the above-described embodiment, the spiral groove 38 is formed on the outer sealed outer peripheral surface 36. However, in the present invention, the spiral groove 38 may be formed on the entire sealed outer peripheral surface 34.

  In the above-described embodiment, a plurality of spiral grooves 38 are formed in the inner ring member 30, but in the present invention, one spiral groove 38 may be formed in the inner ring member 30.

In the above-described embodiment, the plurality of air inflow holes 28 are formed in the outer ring member 20, but in the present invention, one air inflow hole 28 may be formed in the outer ring member 20.

  In the above-described embodiment, the lubricant is the oil 80. However, in the present invention, the lubricant may be a lubricant other than oil such as grease.

  In the above-described embodiment, the cage 50 is made of resin such as reinforced polyamide and formed into a ring body by injection molding or the like. However, in the present invention, other materials made of brass or the like and formed by machining. A cage of the type may be used.

  In the above-described embodiment, the rolling elements are a plurality of balls 40. However, in this invention, the rolling elements are rolling elements of other numbers or types such as a plurality of cylindrical rollers in a single row or a plurality of balls in two rows. It may be.

  The present invention is not limited to such embodiments, and can naturally be implemented in various modes without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Rolling bearing apparatus 20 ... Outer ring member 21 ... Outer ring raceway 25, 26, 27 ... Sealing inner peripheral surface 28 ... Air inflow hole 29 ... Air groove 30 ... Inner ring member 31 ... Inner ring raceway 34, 35, 36 ... Sealing outer peripheral surface 38 Spiral groove 40 Ball (rolling element)
60, 61, 62 ... Labyrinth (labyrinth-like gap)
70 ... Internal space (bearing internal space)
8 ... Clean external space 80 ... Lubricant 9 ... External

Claims (2)

An outer ring member having an outer ring raceway formed on an inner periphery, an inner ring member having an inner ring raceway formed on an outer periphery, and a plurality of rolling elements that roll between the outer ring raceway and the inner ring raceway. A rolling bearing device in which a lubricant is sealed in a bearing inner space between an inner periphery of a member and an outer periphery of the inner ring member, and the inner ring member rotates in one direction,
A cylindrical outer peripheral surface parallel to an axis formed on the outer side of the axial ring bearing from the inner ring raceway on the outer periphery of the inner ring member, and formed on the outer side of the axial bearing from the outer ring raceway on the inner periphery of the outer ring member. And a cylindrical sealing inner peripheral surface parallel to the axis line, and facing each other in the radial direction to form a labyrinth-like gap that seals the bearing internal space,
A spiral groove twisted with respect to the axis of the rolling bearing device , which is formed on the outer peripheral surface of the seal and generates an air flow from the bearing inner space side toward the outside;
Opening toward the labyrinth-like gap by opening in the sealed inner peripheral surface of the outer ring member, an air inflow hole leading to the clean external space from the labyrinth-like gap is formed,
The sealed inner peripheral surface includes an opening to the labyrinth-shaped gap of the air inflow hole, and an air groove that is recessed radially outward in a direction perpendicular to the axis is formed over the entire circumference. Rolling bearing device.   The rolling bearing device according to claim 1, wherein the spiral groove is formed on the outer side of the air inflow hole in the axial direction.

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