JP2011144899A - Double row rolling bearing - Google Patents

Abstract

Even if a seal ring is not provided, it is possible to ensure the sealing performance of the openings at both ends in the axial direction of the bearing space 7 in which the rolling elements 5 and 5 are installed, and the axial dimension can be reduced by the absence of the seal ring. Realize a structure that can be reduced.
An inner diameter side and an outer diameter side in a state of projecting toward the outer peripheral surface of an inner ring 4 and the inner peripheral surface of an outer ring 2 at both inner and outer peripheral edge portions of rim portions 15 and 15 of the cages 14 and 14, respectively. The flanges 16 and 17 are provided over the entire circumference. The inner and outer peripheral surfaces of the inner and outer diameter side flanges 16 and 17 and the outer peripheral surface of the inner ring 4 and the inner peripheral surface of the outer ring 2 facing the inner and outer peripheral surfaces are made to face each other. In this case, the sizes ti and to of the gaps between the inner and outer peripheral surfaces of the flange portions 16 and 17 on the inner diameter side and the outer diameter side and the outer peripheral surface of the inner ring 4 and the inner peripheral surface of the outer ring 2 are all set. Necessary to ensure the sealing performance set between the tip edge of this seal ring and the mating surface when it is assumed that a non-contact type seal ring is provided at the opening of the bearing space 7 over the circumference. It is regulated to the same extent as the gap.
[Selection] Figure 1

Description

  The present invention relates to a double-row angular contact ball bearing, a double-row deep groove ball bearing, a double-row cylindrical roller bearing, and a double-row tapered roller bearing that constitutes a rotation support portion of various rotary machine devices such as various pumps such as submersible pumps. It is related with improvement of double row rolling bearings. Specifically, without providing a seal ring, it is possible to ensure the sealing performance of the opening portions at both ends in the axial direction of the bearing space in which the respective rolling elements are installed, and the axial dimension can be reduced as much as this seal ring is not provided. The structure is realized.

  As a rolling bearing for constituting the rotation support part of various rotating machinery devices, a double-row rolling bearing as shown in FIGS. 3 and 4 is, for example, a part that needs to support a large radial load or a bidirectional axial load. It is used for parts that need to be done, parts that require high support rigidity, and the like. Each of these double-row rolling bearings shown in FIGS. 3 and 4 includes an outer ring 2 having double-row outer ring raceways 1 and 1 on the inner peripheral surface, and an inner ring 4 having double-row inner ring raceways 3 and 3 on the outer peripheral surface. In addition, a plurality of rolling elements 5 and 5 are provided between the outer ring raceways 1 and 1 and the inner ring raceways 3 and 3, respectively, so as to be freely rollable in both rows. The rolling elements 5 and 5 in both rows are held by the cages 6 and 6 so as to be freely rollable. Further, both ends in the axial direction of the bearing space 7 in which the respective rolling elements 5 and 5 are installed are closed by a pair of seal rings 8 and 8.

  3 shows a structure in which contact-type seal rings 8 and 8 are provided, that is, elastic members 9 and 9 constituting the radially inner end portions of the seal rings 8 and 8 are arranged inside the inner ring 4. The structure is shown in sliding contact with seal grooves 10 and 10 provided at both ends in the axial direction of the peripheral surface. FIG. 4 shows a structure in which non-contact type seal rings 8 and 8 (shield rings) are provided, that is, the radially inner ends of the seal rings 8 and 8 are also used as the edges of the seal grooves 10 and 10. The structure is shown to face each other through a gap. The seal rings 8 and 8 prevent grease from leaking from the bearing space 7 in which the rolling elements 5 and 5 are installed, and foreign matters such as dust from entering the bearing space 7 from the outside.

  Further, in the case of the illustrated example, a double row angular contact ball bearing is used in which balls are used as the rolling elements 5 and 5 and a contact angle of a rear combination type is provided. Although not shown in the drawings, as the double row rolling bearing, in addition to such a double row angular type ball bearing, a double row deep groove type ball bearing, a double row cylindrical roller bearing in which each rolling element is a cylindrical roller, A double row tapered roller bearing having a moving roller as a tapered roller may be used. In any case, for example, the outer ring 2 is fitted and fixed to an outer member such as a housing, and the inner ring 4 is fitted and fixed to an inner member such as a rotating shaft to the rotating member. (Or support the rotating member around the support shaft).

  In the case of the double-row rolling bearing shown in FIGS. 3 and 4 described above, both ends in the axial direction of the bearing space 7 in which the rolling elements 5 and 5 are installed are closed by a pair of seal rings 8 and 8. In the case of such a structure, the axial dimension of the double row rolling bearing is increased by the provision of both the seal rings 8 and 8. That is, at the both ends in the axial direction of the double row rolling bearing, portions that support the seal rings 8 and 8 on the outer ring races 1, 1 and the inner ring races 3, 3, respectively. In addition, the axial dimension of the double-row rolling bearing is increased by providing a portion where the tip edges of the seal rings 8 and 8 are in sliding contact or close to each other.

  Such an increase in the axial dimension leads to a decrease in the ease of incorporation into a part with a limited axial dimension (ease of incorporation), and also hinders the downsizing of a mechanical device incorporating a double row rolling bearing. This is not preferable. In addition, when incorporated in a portion with a limited axial dimension, the size of each of the rolling elements 5, 5 (ball diameter, axial dimension in the case of a roller bearing) must be reduced. Therefore, it may be difficult to ensure the rated load and the durability (life) of the rolling elements 5 and 5.

  On the other hand, in Patent Document 1, as shown in FIG. 5, with respect to the single-row rolling bearing 11, only one of the opening portions on the both ends in the axial direction (the left side in FIG. 5) is a non-contact contact type. A structure closed by a seal ring 8 is described. In the case of the structure described in Patent Document 1, the rim portion 12 of the retainer 6a is not closed with the other opening (right side in FIG. 5) of the openings in the axial direction at the other end (the right side in FIG. 5). The peripheral surfaces of the pair of flanges 13 and 13 provided on both the inner and outer peripheral surfaces of the inner ring and the outer ring 2 are opposed to the inner peripheral surface of the outer ring 2a and the outer peripheral surface of the inner ring 4a. Based on the presence of the flanges 13 and 13, the grease is prevented from flowing out from the bearing space 7a in which the rolling elements 5 and 5 are installed through the other opening.

  However, in the case of such a structure described in Patent Document 1, when a single row rolling bearing 11 shown in FIG. 5 is used to form a double row combined rolling bearing, it is blocked by a seal ring. The other openings that are not present are combined in a state of being attached to each other. For this reason, in the state in which the double-row combined rolling bearing is configured in this way, the axial direction of the bearing space 7a in which the rolling elements 5 and 5 are installed is the same as the double-row rolling bearing shown in FIGS. Both end openings are closed by a pair of seal rings 8. Therefore, also in the case of the structure described in Patent Document 1, when a double-row rolling bearing is configured, the axial dimension becomes large as in the structure shown in FIGS. May cause such inconvenience.

  In view of the circumstances as described above, the present invention can ensure the sealability of the opening portions in the axial direction of the bearing space in which each rolling element is installed without providing a seal ring, and does not provide this seal ring. Invented to realize a structure capable of reducing the axial dimension.

The double-row rolling bearing of the present invention (for example, a double-row angular ball bearing, a double-row deep groove ball bearing, a double-row cylindrical roller bearing, a double-row tapered roller bearing, etc.) includes an outer ring, an inner ring, and a plurality of rolling elements. (Balls, cylindrical rollers, tapered rollers, etc.) and a cage.
Among these, the outer ring has a double row outer ring raceway on the inner peripheral surface.
The inner ring has double-row inner ring raceways on the outer peripheral surface.
Further, a plurality of rolling elements are provided between the outer ring raceways and the inner ring raceways so as to be freely rollable in both rows.
Moreover, the said holder | retainer hold | maintains each rolling element of the said both rows so that rolling is possible.

  In particular, in the double-row rolling bearing of the present invention, the opening portions in the axial direction of the bearing space where the rolling elements are installed are not blocked by the seal ring. Instead of being blocked by such a seal ring, the cage is provided with an annular rim portion on each axially open end side of the bearing space. Along with this, both the inner and outer peripheral edge portions (inner peripheral surface, outer peripheral surface, side surface) of these rim portions, and the opposing surfaces of the inner ring and outer ring (outer peripheral surface, inner peripheral surface, Assuming that the clearance between the seal ring and the other side of the seal ring is provided over the entire circumference and a non-contact seal ring is provided in the opening of the bearing space, It is regulated to the same size as the gap required to secure the sealing performance.

More preferably, when the double row rolling bearing of the present invention as described above is carried out, the outer peripheral surface of the inner ring and the outer ring of the inner ring are formed on the inner and outer peripheral portions of the both rim parts as in the invention described in claim 2. The inner diameter side and outer diameter side flanges are provided over the entire circumference in a state of projecting toward the inner peripheral surface. And the gap between the inner and outer peripheral edge portions (inner peripheral surface, outer peripheral surface, side surface) of each flange on the inner diameter side and outer diameter side and the mating surfaces (outer peripheral surface, inner peripheral surface, side surface) of the inner ring and outer ring. Regulate the size.
Further, as in the invention described in claim 3, the mating surface of the outer ring is parallel to the inner peripheral surface of the outer ring or a virtual plane that is provided on the outer ring and is orthogonal to the central axis of the outer ring. A side surface (for example, a side surface of a step provided on the inner peripheral surface of the outer ring, an axially outer end surface of the outer ring). In addition, the inner ring mating surface is the outer peripheral surface of the inner ring or a side surface (for example, a step provided on the outer peripheral surface of the inner ring) provided on the inner ring and parallel to a virtual plane orthogonal to the central axis of the inner ring. Side surface, axially outer end surface of the inner ring).

According to the double row rolling bearing of the present invention configured as described above, it is possible to ensure the sealing performance of the opening portions in the axial direction of the bearing space in which the rolling elements are installed without providing a seal ring. Since the ring is not provided, the axial dimension can be reduced.
That is, the inner and outer peripheral edge portions of each rim portion of the cage located at both axial ends of the bearing space and the inner and outer peripheral surfaces facing the inner and outer peripheral edge portions are non-contact type seals. It faces through a gap similar to the ring. For this reason, grease acts to leak from the openings in both axial ends of the bearing space, and foreign matters such as dust enter the bearing space from the outside by the action of the inner and outer peripheral portions of each rim portion of the cage. Can be prevented. Then, the dimensions of the portions of the inner ring and the outer ring that are off from the inner ring raceway and the outer ring raceway in the axial direction at the both end portions in the axial direction of the inner ring and the outer ring are reduced to the extent that the opening portions in the axial direction of the bearing space need not be blocked by the seal ring. The size of the inner ring and the outer ring as a whole in the axial direction can also be reduced. As a result, the double row rolling bearing having a sealing function can be easily incorporated in a portion having a limited axial dimension, and the various mechanical devices incorporating the double row rolling bearing can be miniaturized. At the same time, even when installing in parts with limited axial dimensions, it is possible to incorporate double row rolling bearings with rolling elements of larger dimensions, ensuring the rated load and durability (long life) Can be easily achieved.

The fragmentary sectional view which shows the 1st example of embodiment of this invention. The fragmentary sectional view which shows the 2nd example. Sectional drawing which shows the 1st example of a conventional structure. Sectional drawing which shows the 2nd example. Sectional drawing which shows the conventional structure regarding a single row rolling bearing.

[First example of embodiment]
FIG. 1 shows a first example of an embodiment of the present invention. The feature of this example is that the shape of the cages 14 and 14 is devised so as to seal the both axial openings of the bearing space 7 without providing a seal ring. The structure and operation of the other parts are the same as those of the conventional structure shown in FIGS.

  In the case of this example, both axial end openings of the bearing space 7 in which the rolling elements 5 and 5 are installed are provided with seal rings 8 and 8 (FIGS. 3 and 4) as in the conventional structure shown in FIGS. 4) Not closed. In the case of this example, instead of not being blocked by such seal rings 8 and 8 (no seal rings 8 and 8 are provided), the rolling elements 5 and 5 are rotatably held for each row. The inner and outer peripheral edge portions of the rim portions 15 and 15 of the pair of retainers 14 and 14 (inner diameter side and outer diameter side flange portions 16 and 17 provided on both ends) are axially opposite ends of the outer peripheral surface of the inner ring 4; In addition, the axially opposite ends of the inner peripheral surface of the outer ring 2 are made to face each other.

  That is, in the case of this example, the cages 14 and 14 are axially arranged from the annular rim portions 15 and 15 and a plurality of circumferentially equidistant positions on one side of the rim portions 15 and 15, respectively. It is set as the crown type holder | retainer provided with the pillar parts 18 and 18 provided in the state extended in this. The rolling elements 5 and 5 are rotatably held in pockets 19 and 19 surrounded by the rim portions 8 and 8 and a pair of column portions 18 and 18 adjacent in the circumferential direction. ing. And in the case of this example, each said holder | retainer 14 and 14 is integrated in the state in which each said rim | limb parts 15 and 15 are located in the axial direction both ends opening part side of the said bearing space 7, respectively.

  In the case of this example, the inner and outer peripheral sides of the rim portions 15 and 15 are protruded toward the outer peripheral surface of the inner ring 4 and the inner peripheral surface of the outer ring 2, respectively. The flanges 16 and 17 are provided over the entire circumference. And both the inner and outer peripheral surfaces of the flange portions 16 and 17 on the inner diameter side and the outer diameter side, and the opposing surfaces of the inner ring 4 and the outer ring 2 facing the inner and outer peripheral surfaces, that is, the outer peripheral surfaces of the inner rings 4 The inner ring surface of the outer ring 2 is closely opposed. More specifically, the clearances ti and to of the inner and outer peripheral surfaces of the inner diameter side and outer diameter side flanges 16 and 17 and the outer peripheral surface of the inner ring 4 and the inner peripheral surface of the outer ring 2 are respectively expressed as follows. To ensure the sealing performance set between the tip edge of the seal ring and the mating surface, assuming that a non-contact type seal ring is provided in the opening of the bearing space 7 over the entire circumference. In the case of a double row angular contact ball bearing having a nominal number of 5305-5313 (pitch circle diameter 46.5-105 mm, inner ring inner diameter 25-65 mm), It is restricted to 0.6 to 1.2% of the inner diameter of the inner ring. For example, the sizes of the gaps ti and to are determined according to the size of the double row rolling bearing, and the non-contact type seal rings 8 and 8 (shields) of the double row rolling bearing with seal ring shown in FIG. The size of the gap between the tip of the ring) and the edges of the seal grooves 10 and 10 (see FIG. 4) is approximately the same.

  The sizes ti and to of the clearances are the sizes of the clearances 14 and 14 when the rolling elements 5 and 5 guide the rolling bodies 5 and 5, respectively. Let ti and to be substantially the same (ti .apprxeq.to). In this case, both the sizes ti and to of these gaps are set within a range of 0.6 to 1.2% of the inner diameter of the inner ring. In the case of adopting such a rolling element guide structure, pocket clearances (particularly between the inner surfaces of the pockets 19 and 19 of the cages 14 and 14 and the rolling elements and the rolling surfaces of the rolling elements 5 and 5). The radial gap is made as small as possible within a range that does not hinder the incorporation of the lubricant into the pocket gaps, and the radial displacement of the cages 14 and 14 is suppressed.

  On the other hand, when the cages 14 and 14 are used as raceway guides, the sizes ti and to of the gaps are regulated as follows. In other words, when the cages 14 and 14 are guided by the inner ring 4 {inner ring guide}, the clearance between the outer circumferential surface of the inner ring 4 and the inner circumferential surface of the inner diameter side flanges 16 and 16 is determined. The size t i is made smaller than the size t o of the gap between the inner peripheral surface of the outer ring 2 and the outer peripheral surfaces of the outer diameter side flanges 17 and 17 (ti <to). Further, in the case where the cages 14 and 14 are guided by the outer ring 2 (to be an outer ring guide), the gap between the inner peripheral surface of the outer ring 2 and the outer peripheral surfaces of the outer diameter side flange portions 17 and 17 is used. Is made smaller than the size t i of the gap between the outer peripheral surface of the inner ring 4 and the inner peripheral surfaces of the inner diameter side flanges 16 and 16 (to <ti). Even when such a raceway guide structure is employed, the larger gap to (t i) falls within the range of 0.6 to 1.2% of the inner ring inner diameter. For the guide of the bearing ring, the gap in the portion adjacent to the inner peripheral surface of the inner ring 4 or the inner peripheral surface of the outer ring 2 may be less than 0.6% of the inner diameter of the inner ring.

In the case of this example configured as described above, it is possible to ensure the sealability of the openings at both ends in the axial direction of the bearing space 7 in which the rolling elements 5 and 5 are installed without providing a seal ring. Since the ring is not provided, the axial dimension can be reduced.
That is, as described above, the inner and outer peripheral surfaces of the inner diameter side and outer diameter side flanges 16 and 17 located at both axial ends of the bearing space 7 and the inner ring 4 facing both the inner and outer peripheral surfaces. And both the outer and inner peripheral surfaces of the outer ring 2 are opposed to each other through a gap having the same size as that of the non-contact type seal ring. For this reason, grease leaks from the openings in the both axial ends of the bearing space 7 based on the presence of the flange portions 16 and 17 on the inner diameter side and the outer diameter side, and foreign matter such as dust is introduced into the bearing space 7. It can prevent entering from the outside.

  Then, the axial ends of the bearing space 7 need not be blocked by the seal ring, so that the axial ends of the inner ring 4 and the outer ring 2 deviate from the inner ring raceway 3 and the outer ring raceway 1, respectively. Therefore, the dimensions of the inner ring 4 and the outer ring 2 as a whole in the axial direction can also be reduced. As a result, the double row rolling bearing having a sealing function can be easily incorporated in a portion having a limited axial dimension, and the various mechanical devices incorporating the double row rolling bearing can be miniaturized. At the same time, a double row rolling bearing provided with rolling elements 5 and 5 having larger dimensions can be incorporated even in a case where the axial dimension is limited, and the rated load and durability can be ensured accordingly. Long life) can be easily achieved.

[Second Example of Embodiment]
FIG. 2 shows a second example of the embodiment of the present invention. In the case of this example, the inner diameter side stepped portions 20 and 20 are respectively provided at both axial ends of the outer peripheral surface of the inner ring 4 so as to be recessed radially inward from the outer peripheral surface. Also, outer diameter side step portions 21 and 21 are provided at both axial ends of the inner peripheral surface of the outer ring 2 so as to be recessed radially outward from the inner peripheral surface. And the inner diameter side and outer diameter side stepped portions facing the side surfaces of the inner diameter side and outer diameter side flanges 16a and 17a provided on the rim portions 15a and 15a of the cages 14a and 14a, respectively. The side surfaces 20 and 21 (side surfaces parallel to a virtual plane orthogonal to the central axes of the inner ring 4 and the outer ring 2) are made to face each other over the entire circumference. In the case of this example, the clearances t i, t o between these side surfaces are assumed to be provided with a non-contact type seal ring at the opening of the bearing space 7 and the opposite end edge of this seal ring The clearance is set to the same level as the clearance required to ensure the sealing performance (for example, in the case of a double-row angular contact ball bearing with a nominal number of 5305-5313, the inner ring has an inner diameter of 0. 6-1.2%). In the case of this example, the pocket gaps (particularly the axial gaps) of the cages 14a and 14a are kept small so that the side surfaces do not slide with each other (ti and to do not disappear).

In the case of this example, compared to the structure of the first example of the above-described embodiment, it is easy to secure the area of the portion where the side surfaces face each other, and the amount of the gap (to the extent that the facing area can be increased) is increased. Even if the sizes ti and to are increased, the sealing performance can be easily ensured (the same sealing performance can be ensured even if the gap sizes ti and to are large). In the case of this example, only the gap sizes ti and to between the side surfaces of the inner diameter side and outer diameter side step portions 20 and 21 and the side surfaces of the inner diameter side and outer diameter side flange portions 16a and 16b are provided. As described above, the clearance is regulated to the same extent as the clearance of the non-contact type seal ring. The sizes Ti and To of the gaps between the outer peripheral surface and the inner peripheral surface of the radial flanges 16a and 16b can be similarly regulated.
Since other configurations and operations are the same as those of the first example of the embodiment described above, illustration and description regarding equivalent parts are omitted.

  Although not shown in the drawings, the inner ring 4 and the outer ring 2 are not provided with the inner diameter side and outer diameter side step portions 20 and 21 as described above, and the axial direction from both axial ends of the inner ring 4 and the outer ring 2 is axial. The rim portion of the cage is protruded to the outside, and the side surfaces of the protruded rim portion (inner diameter side and outer diameter side flanges) are made to face each other in the axial direction both end surfaces of the inner ring 4 and the outer ring 2. You can also do things. The types of the cages 14 and 14a are not limited to the crown type as shown in FIGS. 1 and 2, but have rim portions at both ends in the axial direction (one pair of rim portions is provided for each column). It is also possible to use a bowl-shaped one (a bowl-shaped retainer) that is connected by a portion. In this case, the inner and outer peripheral edges of the respective rim portions (the inner diameter side and outer diameter side flanges) located on the both axial end opening sides of the bearing space 7 are made to face the inner ring 4 and the outer ring 2 close to each other.

  1 and 2 show a structure in which the cages 14 and 14a are provided for each row of the rolling elements 5 and 5 (a pair of cages 14 and 14a is provided). The rolling elements 5 and 5 can be held by a single cage. In this case, the inner and outer peripheral edges of the rim portions (inner diameter side and outer diameter side flanges) provided at both ends in the axial direction are brought close to and opposed to the mating surfaces of the inner ring 4 and the outer ring 2, respectively. Further, in the case of the first example of the above-described embodiment, the respective surfaces (inner peripheral surface, outer peripheral surface, and side surface) that serve as a seal by being opposed to each other are the centers of the inner ring 4 and the outer ring 2. Similarly, in the case of the second example, the peripheral surface is parallel to the axis, and the side surface is parallel to a virtual plane orthogonal to the central axis of the inner ring 4 and the outer ring 2, but is not limited thereto. If the necessary sealing performance can be ensured, the above surfaces can be inclined with respect to the central axis (surfaces having angles with the central axis of, for example, 45 degrees, 60 degrees, etc.).

DESCRIPTION OF SYMBOLS 1 Outer ring raceway 2, 2a Outer ring 3 Inner ring raceway 4, 4a Inner ring 5 Rolling element 6, 6a Cage 7, 7a Bearing space 8 Seal ring 9 Elastic material 10 Seal groove 11 Single row rolling bearing 12 Rim part 13 Ridge part 14, 14a Cage 15, 15a Rim part 16, 16a Inner diameter side flange 17, 17a Outer diameter side flange 18 Column part 19 Pocket 20 Inner diameter side step part 21 Outer diameter side step part

Japanese Patent Laid-Open No. 2002-235751

Claims (3)

An outer ring having a double row outer ring raceway on the inner peripheral surface, an inner ring having a double row inner ring raceway on the outer peripheral surface, and a plurality of rollings for each row between the outer ring raceways and the inner ring raceways. In a double row rolling bearing comprising a rolling element provided freely, and a cage that holds the rolling elements of both rows freely.
The cage is provided with an annular rim portion on each axial end opening side of the bearing space without closing the axial end openings of the bearing space where the rolling elements are installed with seal rings. In addition, the size of the gap between the inner and outer peripheral edge portions of the both rim portions and the mating surfaces of the inner ring and the outer ring facing the inner and outer peripheral edge portions is extended over the entire circumference, and the bearing space Assuming that a non-contact type seal ring is provided in the opening, it is the same as the size of the gap that is set between the leading edge of this seal ring and the mating surface and is necessary to ensure the sealing performance. Double-row rolling bearing characterized by being regulated to a certain extent.   On the inner and outer peripheral portions of both rims, the inner diameter side and outer diameter side flanges are provided over the entire circumference in a state of projecting toward the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring. The double row rolling bearing according to claim 1, wherein the size of the gap between the inner and outer peripheral edge portions of each side flange and the mating surfaces of the inner ring and the outer ring is regulated.   The mating surface of the outer ring is the inner circumferential surface of the outer ring or a side surface provided on the outer ring and parallel to a virtual plane perpendicular to the central axis of the outer ring, and the mating surface of the inner ring is the outer circumference of the inner ring. The double row rolling bearing according to any one of claims 1 and 2, which is a surface or a side surface provided on the inner ring and parallel to a virtual plane orthogonal to the central axis of the inner ring.

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