JP2009174611A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing capable of reducing bearing pressure of a rolling element held near an end part in the peripheral direction of cage constituting parts, in the rolling bearing for holding the rolling element at a predetermined interval in the peripheral direction by a rolling element holding part arranged in the cage constituting parts, by constituting a cage for holding the rolling element out of a plurality of cage constituting parts arranged in a different position in the peripheral direction. <P>SOLUTION: This rolling bearing 1 includes an outer ring 2b, a plurality of first rolling elements 3 arranged in the peripheral direction of the outer ring in a space between the outer ring and a rotary shaft 2a inside of the outer ring, and the cage 5 holding the first rolling elements, and is provided by constituting the cage of the plurality of cage constituting parts 51 and 52 arranged in the different position in the peripheral direction, and is formed for holding the first rolling element at the predetermined interval in the peripheral direction by a rolling element holding part arranged between both end parts in the peripheral direction in the cage constituting parts. A second rolling element 30 is arranged between the adjacent cage constituting parts in the peripheral direction among the plurality of cage constituting parts. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rolling bearing, and in particular, includes a plurality of rolling elements arranged along a circumferential direction of an outer ring in a space between an outer ring and a rotating shaft, and a cage that holds the rolling element, It is composed of a plurality of cage components arranged at different positions along the circumferential direction, and the rolling elements are arranged along the circumferential direction by the rolling element holders arranged along the circumferential direction in the cage components. The present invention relates to a rolling bearing that is held at an interval.

  A rolling bearing is known in which a plurality of rolling elements are disposed between an outer peripheral surface of a rotating shaft and an inner peripheral surface of an outer ring via lubricating oil so as to rotatably support the rotating shaft. Examples of such a rolling bearing include those disclosed in Patent Document 1. A rolling bearing may be provided with a cage that holds the rolling elements at a predetermined interval along the circumferential direction of the outer ring (hereinafter simply referred to as the circumferential direction).

  As a cage for a rolling bearing, a split type cage, that is, a cage composed of a plurality of cage components arranged at different positions along the circumferential direction may be used. FIG. 12 is a schematic cross-sectional view in the radial direction showing an example of a rolling bearing in which a split type cage is used.

  In FIG. 12, the code | symbol 100 shows a rolling bearing. The bearing 100 includes an annular race ring 200, a plurality of rolling elements 300 that can roll along the race ring 200, and a cage 500 that holds the rolling elements 300 along the race ring 200 at predetermined intervals. Is provided. The track ring 200 includes a rotating shaft 200a and an outer ring 200b provided outside the rotating shaft 200a. The cage 500 includes a first cage component 501 and a second cage component 502 that are arranged at different positions along the raceway ring 200, that is, along the circumferential direction.

  When the cage 500 is divided, the rotary shaft cannot be assembled with an integrally formed cage, for example, a crankshaft of an internal combustion engine. Even if the rotating shaft has a bent portion, the bearing can be assembled.

JP-A-55-149418

  Here, when the cage is divided, the rolling elements provided near the ends in the circumferential direction among the rolling elements held by the respective cage components are larger than the other rolling elements. There is a problem that surface pressure acts. This is because, as will be described below, it is necessary to increase the length of the end portion to some extent in order to ensure the strength of the end portion in the circumferential direction of the cage component.

  When a rotating shaft rotates, the edge part of the circumferential direction of an adjacent holder | retainer structure part may collide. In this case, in order to suppress the occurrence of deformation, it is required to secure the necessary strength by increasing the length of the circumferential end (the length in the circumferential direction) to some extent. However, in this case, a region where no rolling element that receives a load exists is large at the circumferential end of the cage component. Among adjacent cage components, from the rolling element held at the circumferential end of one cage component to the rolling element held at the circumferential end of the other cage component Is larger than the interval between the other rolling elements (predetermined interval). As a result, a larger surface pressure acts on the rolling element held at a position near the end in the circumferential direction in the cage component, that is, at a position close to the divided portion of the cage as compared with other rolling elements. It becomes.

  The cage for holding the rolling element of the rolling bearing is composed of a plurality of cage components arranged at different positions along the circumferential direction, and the rolling element holding unit arranged along the circumferential direction in the cage component Thus, in a rolling bearing in which the rolling elements are held at a predetermined interval along the circumferential direction, it is hoped that the surface pressure of the rolling elements held near the circumferential end of the cage component can be reduced. It is rare.

  An object of the present invention is that a cage that holds rolling elements of a rolling bearing is composed of a plurality of cage components arranged at different positions along the circumferential direction, and is arranged along the circumferential direction in the cage component. In the rolling bearing in which the rolling element is held at a predetermined interval along the circumferential direction by the rolling element holding part, the surface of the rolling element that is held near the end in the circumferential direction in the cage component It is to provide a rolling bearing capable of reducing the pressure.

  The rolling bearing according to the present invention includes an outer ring, a plurality of first rolling elements disposed along a circumferential direction of the outer ring in a space between the outer ring and a rotating shaft disposed inside the outer ring, A cage that holds the plurality of first rolling elements, wherein the cage is configured with a plurality of cage components disposed at different positions along the circumferential direction, A rolling bearing in which the first rolling elements are held at predetermined intervals along the circumferential direction by rolling element holding parts disposed along the circumferential direction between both ends in the circumferential direction. And the 2nd rolling element is arrange | positioned between the said holder | retainer structure parts adjacent in the said circumferential direction among the said several said holder | retainer structure parts.

  In the rolling bearing of the present invention, a concave portion having a shape corresponding to the shape of the second rolling element is provided at the circumferential end portion of the cage component, and the second portion is provided by the concave portion. The rolling element is held.

  In the rolling bearing according to the present invention, one second rolling element is disposed between the adjacent cage components, and the second rolling element has a diameter that is the same as that of the first rolling element. It is the same and the mass is small compared with the mass of each said 1st rolling element.

  In the rolling bearing of the present invention, a plurality of the second rolling elements are arranged along the axial direction of the outer ring between the adjacent cage constituent parts, and the second rolling elements are One rolling element has the same diameter and is smaller in mass than each of the first rolling elements.

  In the rolling bearing of the present invention, the end in the axial direction of the second rolling elements facing each other is provided at the end in the circumferential direction of the cage component so as to be in contact with each other, A restricting portion for restricting movement of the second rolling element in the axial direction is provided.

  In the rolling bearing of the present invention, two second rolling elements are arranged along the radial direction of the outer ring between the adjacent cage constituent parts, and the second rolling element is The diameter is half the diameter of the first rolling element, and the mass is smaller than the mass of each of the first rolling elements.

  In the rolling bearing of the present invention, the outer ring and the cage are fixed so that the circumferential movement of the cage with respect to the outer ring does not occur.

  In the rolling bearing according to the present invention, the outer ring is divided into a plurality of outer ring constituent parts arranged at different positions along the circumferential direction, and the rolling bearing is a part of the cage constituent part. A restricting means for restricting a range of relative movement of the retainer in the circumferential direction with respect to the outer ring is provided so that an end portion in the circumferential direction does not pass through the split portion of the outer ring.

  According to the present invention, the cage that holds the rolling elements of the rolling bearing is composed of a plurality of cage components arranged at different positions along the circumferential direction, and is arranged along the circumferential direction in the cage component. In the rolling bearing in which the rolling elements are held at predetermined intervals along the circumferential direction by the rolled rolling element holding portion, the second rolling element is disposed between the cage constituent portions adjacent in the circumferential direction. The Thereby, it is suppressed that the space | interval of the rolling element in the circumferential direction edge part of a holder | retainer structure part becomes large, and the surface pressure of the rolling element currently hold | maintained near the edge part of the circumferential direction in a holder | retainer structure part is reduced. Can be reduced.

  Hereinafter, an embodiment of a rolling bearing according to the present invention will be described in detail with reference to the drawings.

(First embodiment)
The first embodiment will be described with reference to FIGS. 1 to 6. In the present embodiment, the cage that holds the rolling elements of the rolling bearing is composed of a plurality of cage components arranged at different positions along the circumferential direction, and is arranged along the circumferential direction in the cage component. Further, the present invention relates to a rolling bearing in which the rolling elements are held at predetermined intervals along the circumferential direction by the rolling element holding portion.

  FIG. 1 is a schematic sectional view in the radial direction of a bearing according to the present embodiment, FIG. 2 is a perspective view of the bearing according to the present embodiment, and FIG. 3 is a partial sectional view in the axial direction of the bearing according to the present embodiment. FIG. 4 is a partial cross-sectional view in the circumferential direction of the bearing according to the present embodiment, and FIG. 5 is an enlarged view of the vicinity of the cage dividing portion of the bearing according to the present embodiment.

  As shown in FIG. 1 and FIG. 2, a bearing 1 as a rolling bearing according to this embodiment has a plurality of rolling elements (first rolling elements) 3 arranged along an annular race 2. A rolling part 4 as means is provided so as to freely roll. The bearing 1 rotatably supports various rotating shafts such as a camshaft and a crankshaft of an internal combustion engine. Hereinafter, although the bearing 1 of this embodiment is demonstrated as what is applied to the rolling bearing which supports the crankshaft of an internal combustion engine rotatably, it is not restricted to this, The rolling bearing which supports the rotating shaft of various apparatuses is also applied. Applicable.

  In the following description, unless otherwise specified, “the axial direction of the bearing” means the axial direction of the rotating shaft supported by the bearing 1, and “the radial direction of the bearing” means a direction orthogonal to the axial direction. The “circumferential direction of the bearing” refers to the direction of rotation about the rotation axis.

  The bearing 1 is provided so as not to move relative to a supported portion such as a crank journal provided on the crankshaft. The bearing 1 is provided so as not to move relative to the supported portion, for example, by fixing an outer ring 2b described later to a housing (not shown). The bearing 1 rotatably supports the rotating shaft 2a of the crankshaft of the internal combustion engine. The crankshaft rotates in the circumferential direction while being supported by the bearing 1 with the reciprocation of a piston (not shown).

  The bearing 1 includes a ring-shaped raceway ring 2 described above, a rolling portion 4 having a plurality of rolling elements 3 that can roll along the raceway ring 2, and a plurality of rolling elements 3 along the raceway ring 2. And a cage 5 as a holding means for holding at intervals.

  The track ring 2 includes a rotation shaft 2a and an outer ring 2b provided outside the rotation shaft 2a. The rotating shaft 2a is formed in a cylindrical shape and forms the axis of the crankshaft. The outer ring 2b is formed in an annular shape (cylindrical shape), and is provided along the outer peripheral surface of the rotation shaft 2a so that the center axis coincides with the center axis of the rotation shaft 2a. That is, the rotating shaft 2a and the outer ring 2b are provided coaxially.

  More specifically, as shown in FIG. 3, an inner raceway surface 2c is formed along the circumferential direction on the outer circumferential surface of the rotating shaft 2a. On the other hand, an outer raceway surface 2d is formed on the inner circumferential surface of the outer ring 2b along the circumferential direction. The rolling part 4 is provided in an annular space formed between the inner raceway surface 2c of the rotating shaft 2a and the outer raceway surface 2d of the outer ring 2b. Further, on both sides in the axial direction of the outer raceway surface 2d, flanges 2e projecting radially inward are formed. In other words, the outer raceway surface 2d is formed in a concave shape on the inner peripheral surface of the outer ring 2b.

  The rolling part 4 has a plurality of rolling elements 3. Each rolling element 3 of this embodiment is a thin cylindrical needle-shaped (needle-shaped) roller. The plurality of rolling elements 3 are provided in an annular space between the inner raceway surface 2 c and the outer raceway surface 2 d so that the direction of the axis (rolling center) of the rolling element 3 is parallel to the axial direction of the bearing 1. . The plurality of rolling elements 3 are arranged at predetermined intervals, here, at regular intervals along the circumferential direction of the inner raceway surface 2c and the outer raceway surface 2d by the cage 5.

  Each rolling element 3 is arranged by a cage 5 so that a rolling surface 3r as an outer peripheral surface can come into contact with the inner raceway surface 2c and the outer raceway surface 2d, and both end faces can come into contact with the flange 2e of the outer ring 2b. Placed in. Accordingly, the plurality of rolling elements 3 roll in the annular space along the inner raceway surface 2c and the outer raceway surface 2d when the rolling surface 3r contacts the inner raceway surface 2c and the outer raceway surface 2d. In addition, the two end surfaces abut against the flange 2e of the outer ring 2b, so that it is prevented from falling off in the axial direction.

  As shown in FIG. 2, the cage 5 includes a pair of annular portions 5a, a plurality of columnar separate portions 5b, and rolling element holding portions 5c on a plurality of slits. The pair of annular portions 5 a make a pair along the axial direction and are provided coaxially with the axis of the raceway ring 2. That is, each annular portion 5a is arranged coaxially with the central axis of the rotation shaft 2a and the outer ring 2b in the annular space between the inner raceway surface 2c and the outer raceway surface 2d. Each annular portion 5a is arranged in such a manner that its outer circumferential surface is continuous in the circumferential direction so as to be able to abut against each flange 2e on both sides of the outer raceway surface 2d, and its inner circumferential surface is able to abut against the inner raceway surface 2c The entire cage 5 is guided and supported along the inner raceway surface 2c and the outer raceway surface 2d together with the plurality of rolling elements 3.

  Each separate part 5b is constructed so as to be spanned along the axial direction between the pair of annular parts 5a. The separate part 5b is provided so as not to roll by fixing both ends to the annular part 5a. The separate part 5b is located between the adjacent rolling elements 3, and a plurality of the separating parts 5b are provided at equal intervals in the circumferential direction at a predetermined interval (an interval corresponding to the outer diameter of the rolling element 3 to be held).

  Each rolling element holding part 5c is a space defined by a pair of annular parts 5a opposed in the axial direction and a pair of separate parts 5b adjacent in the circumferential direction. Each rolling element holding portion 5c individually accommodates one rolling element 3 such that the axis (rolling center) direction of the rolling element 3 is parallel to the axial direction of the bearing 1, and each rolling element 3 is placed on the inner track. It rolls along the circumferential direction of the surface 2c and the outer raceway surface 2d. The rolling element 3 and the cage 5 are made of, for example, metal (steel material or the like).

  In the bearing 1 configured as described above, in the annular space between the inner raceway surface 2c of the rotating shaft 2a and the outer raceway surface 2d of the outer ring 2b, a plurality of rolling elements 3 are arranged on the inner raceway surface 2c via lubricating oil. And revolves along the inner raceway surface 2c and the outer raceway surface 2d while rolling (spinning) on the inner raceway surface 2c and the outer raceway surface 2d in contact with the outer raceway surface 2d. That is, the bearing 1 supports the rotating shaft 2a so as to be rotatable with respect to the outer ring 2b by sliding the inner raceway surface 2c and the outer raceway surface 2d of the raceway ring 2 and the rolling surface 3r of each rolling element 3. To do. At this time, the cage 5 is guided along the inner raceway surface 2c and the outer raceway surface 2d by the annular portion 5a in accordance with the relative rotation of the rotating shaft 2a with respect to the outer ring 2b, and each rolling element holding portion 5c. The rolling elements 3 housed therein are rotated relative to the raceway ring 2 while being held at equal intervals along the raceway ring 2.

  A separate portion 5b provided in the cage 5 regulates contact between adjacent rolling elements 3 in the circumferential direction. During this time, the bearing 1 receives a radial load (a direction perpendicular to the axial direction, that is, a radial load) as a load by the rolling surface 3r of the rolling element 3 that contacts the inner raceway surface 2c and the outer raceway surface 2d. In addition, a slight axial load (a load in the axial direction) can be received as a load by the end surface portion of the rolling element 3 that comes into contact with the flange 2e.

  In the bearing 1 of the present embodiment, the outer ring 2b and the cage 5 are divided. As shown in FIGS. 1 and 2, the outer ring 2b is divided into a first outer ring constituting part 21b and a second outer ring constituting part 22b arranged at different positions along the circumferential direction in the outer ring dividing part 2s. Yes. The shape (the shape of the end portion in the circumferential direction) of the first outer ring constituting portion 21b and the second outer ring constituting portion 22b in the split portion 2s is formed in a convex shape in which one of them protrudes in the circumferential direction, and the other is It is formed in the concave shape corresponding to.

  The cage 5 is divided into a first cage component 51 and a second cage component 52 arranged at different positions along the circumferential direction in the cage divider 5s. In the present embodiment, the cage 5 includes two cage components 51, 51 such that the circumferential length of the first cage component 51 and the circumferential length of the second cage component 52 are equal. It is divided into 52. In this way, when the cage 5 and the outer ring 2b are divided, the bearing 1 can be attached to and detached from a rotating shaft that cannot be attached or detached, for example, the rotating shaft 2a of the crankshaft when they are integrally formed. Can be done.

  However, as described above with reference to FIG. 12, when the cage 500 is a split type, among the plurality of rolling elements 300 held by the cage components 501 and 502, it is closer to the end in the circumferential direction. In addition to the rolling element 300 (see reference numeral 300a) provided in the rolling element 300, the other rolling element 300 (the rolling element 300 disposed in the central portion in the circumferential direction) is arranged with respect to the rolling element 300 disposed near the end in the circumferential direction. There is a problem that a large surface pressure acts as compared to.

  As shown in FIGS. 1 and 2, in the bearing 1 of the present embodiment, the second rolling element 30 is provided between the first cage component 51 and the second cage component 52. When the second rolling element 30 receives a radial load between the first cage component 51 and the second cage component 52, a plurality of rolling elements held by the cage components 51, 52 are provided. 3, the radial load received by the rolling element 3 disposed near the end in the circumferential direction, including the rolling element 3 provided closest to the end in the circumferential direction (hereinafter referred to as the end rolling element 3e). It is possible to reduce the surface pressure of the rolling elements 3 that are dispersed and arranged closer to the end in the circumferential direction.

  The second rolling element 30 is a thin cylindrical needle-like (needle-like) roller similar to the rolling element 3 and is made of the same material as the rolling element 3. The diameter of the second rolling element 30 is formed to be equal to the diameter of the rolling element 3. The length of the second rolling element 30 in the axial direction (see reference numeral L1 in FIG. 4) is equal to the length of the rolling element 3 in the axial direction. That is, the second rolling element 30 is formed so that the contact area between the inner raceway surface 2c and the outer raceway surface 2d is equal to that of the rolling element 3. The 2nd rolling element 30 is arrange | positioned 1 each at each holder | retainer division | segmentation part 5s. In the second rolling element 30, the direction of the axis (rolling center) of the second rolling element 30 is parallel to the axial direction of the bearing 1 in an annular space between the inner raceway surface 2c and the outer raceway surface 2d. It is provided as follows.

  FIG. 4 is a partial cross-sectional view in the circumferential direction of the bearing according to the present embodiment. As shown in FIG. 4, at the circumferential ends of the cage components 51 and 52, the annular portion 5 a has a shape protruding in the circumferential direction as compared to the separate portion 5 b. Thereby, the holding | maintenance part 54 holding the 2nd rolling element 30 is comprised by a pair of cyclic | annular part 5a and each separate part 5b of the holder | retainer structure parts 51 and 52. As shown in FIG. As shown in FIG. 1, the second rolling element 30 is arranged such that the rolling surface 30 r that is the outer peripheral surface can contact the inner raceway surface 2 c and the outer raceway surface 2 d. Further, as shown in FIG. 4, the second rolling element 30 can have both end surfaces abutted against the pair of annular portions 5a, and the rolling surface 30r can be connected to the separating portion 5b of the cage constituting portions 51 and 52. It arrange | positions so that contact | abutment is possible.

  The second rolling element 30 rolls along the circumferential direction of the inner raceway surface 2 c and the outer raceway surface 2 d while being held by the holding portion 54. Since the second rolling element 30 is disposed so that both end surfaces can come into contact with the pair of annular portions 5a, the second rolling element 30 is suppressed from moving in the axial direction. In addition, since the second rolling element 30 is disposed so as to be able to contact the separating portion 5 b of the cage constituting portions 51 and 52, the direction of the axis (rolling center) is parallel to the axial direction of the bearing 1. Kept.

  As shown in FIG. 1 and FIG. 5, a holding groove 55 for holding the second rolling element 30 is provided at the circumferential end portion (separate portion 5 b) of the cage constituting portions 51 and 52. The holding groove 55 is formed in a shape corresponding to the shape of the second rolling element 30, forming a concave portion that is recessed in the circumferential direction. The holding groove 55 of the present embodiment has a circular cross section in the radial direction. The 2nd rolling element 30 rolls in the state hold | maintained at the holding groove | channel 55 provided in the holder | retainer structure parts 51 and 52, respectively. Thereby, the state where the direction of the axis (rolling center) of the second rolling element 30 and the direction of the axis of the bearing 1 are parallel can be more reliably maintained.

  Further, since the holding groove 55 is provided, the split type cage 5 can be efficiently attached and detached. For example, when the case where the cage 5 is assembled to the rotary shaft 2a is described as an example, the first cage component 51 is brought into contact with the rotary shaft 2a from below the rotary shaft 2a. Next, when the second cage component 52 is combined with the first cage component 51 from above, the second rolling element 30 is set in the holding groove 55 of the first cage component 51 in advance. Thereby, the 2nd rolling element 30 can be positioned easily, without the 2nd rolling element 30 rolling and dropping | omitting during an assembly | attachment operation | work.

  When the cage 5 is divided by the two cage dividing portions 5s, the second rolling elements 30 are arranged in the two cage dividing portions 5s, thereby reducing the number of rolling bodies in the bearing 1 to 2. Can be increased.

  When the cage dividing portion 5s enters the load zone with the rotation of the rotating shaft 2a, since the second rolling element 30 receives a radial load, compared to the case where the second rolling element 30 is not arranged, The radial load received by the end rolling element 3e can be dispersed, and the surface pressure of the end rolling element 3e can be reduced. The second rolling element 30 is disposed between the end rolling element 3e of the first cage component 51 and the end rolling element 3e of the second cage component 52 so that the second rolling element 30 is provided. It is possible to reduce the surface pressure of the end rolling element 3e by about 1.5 times (reducing the surface pressure by two thirds) compared to the case where is not disposed. Moreover, conventionally, since it was necessary to enlarge the space | interval of the edge rolling elements 3e to some extent in order to ensure the intensity | strength of the edge part of the circumferential direction of the holder | retainer 5, the space | interval of the rolling elements 3 is made equal. It was difficult. In this embodiment, by disposing the second rolling element 30, the distance between the end rolling element 3e and the second rolling element 30 is equal to the distance between the other rolling elements 3, and each rolling element 3, It is possible to make 30 intervals uniform throughout the bearing 1. Thereby, the surface pressure of each rolling element 3 and 30 can be equalized.

  Conventionally, rolling bearings are subject to radial loads due to line contact, and therefore have been subject to large physique, reduced life, increased noise, and the like. According to the present embodiment, as described below, the problems in these rolling bearings can be solved. As described above, according to the present embodiment, the number of rolling elements 3, 30 provided in the bearing 1 is increased as compared with a conventional bearing (a bearing in which the second rolling element 30 is not provided). Can do. Therefore, as will be described below, the size of the bearing 1 can be reduced compared to the conventional case, the life of the bearing 1 can be extended, and the durability can be improved.

  FIG. 6 is a diagram showing the relationship between the number of rolling elements (rollers) and the life of the bearing. As shown in FIG. 6, generally, if the size of the bearing 1 is the same, the life of the bearing 1 becomes longer as the number of the rolling elements 3, 30 arranged increases. This is because when the number of rolling elements 3 and 30 increases, the load received by each rolling element 3 and 30 decreases. In the present embodiment, by increasing the number of rolling elements 3 and 30 that can be arranged on the bearing 1, the life of the bearing 1 remains as it is, or the life is extended, or the body is made small while ensuring the same life. Can do.

  Further, in the present embodiment, the surface pressure of each rolling element 3, 30 is equalized, thereby suppressing the radial load from concentrating on the specific rolling element 3 and extending the life of the bearing 1. Further, by reducing the load received by each rolling element 3, 30 and equalizing the surface pressure of each rolling element 3, 30, the occurrence of defects such as seizure is suppressed, and the reliability of bearing 1 is improved. The noise generated in the bearing 1 can be reduced.

  According to the present embodiment, a great effect can be obtained particularly in terms of noise reduction. For example, it is possible to reduce the intermittent sound that occurs when the rolling element 3 rides on the outer ring splitting portion 2s. In the outer ring split portion 2s, there are slight steps or gaps on the outer raceway surface 2d between the first outer ring constituting portion 21b and the second outer ring constituting portion 22b. When the intervals between the rolling elements 3 are not uniform, for example, in the bearing 100 (FIG. 12) where the second rolling elements 30 are not arranged, the intervals between the end rolling elements 300 a are the intervals between the other rolling elements 300. If it is larger than the difference, the riding sound when the rolling element 300 rides on the step becomes uneven and an intermittent sound is generated. In this embodiment, the noise by such a discontinuous sound can be suppressed by arrange | positioning the 2nd rolling element 30 and equalizing the space | interval of each rolling element 3 and 30. FIG. Further, since the rotation of the entire bearing 1 becomes smooth (load distribution is uniform), noise can be reduced.

  By providing the second rolling element 30 in the cage dividing portion 5s, as will be described below, the cage constituting portions 51 and 52 collide with a step on the outer raceway surface 2d to generate a collision sound or rotate. It can suppress that resistance increases. When the second rolling element 30 receives the radial load, even if the cage split portion 5s enters the load zone, the decrease in the distance between the inner raceway surface 2c and the outer raceway surface 2d is suppressed. For this reason, it is suppressed that the holder | retainer structure parts 51 and 52 approach the outer track surface 2d. Further, since the cage constituent portions 51 and 52 hold the second rolling element 30 in the holding groove 55, the end portions of the cage constituent portions 51 and 52 are suppressed from moving in the radial direction. Therefore, it is suppressed that the edge part of cage structure parts 51 and 52 approaches outer track surface 2d, and cage structure parts 51 and 52 collide with the level difference of outer track surface 2d.

  By disposing the second rolling element 30, the oil amount distribution in the circumferential direction in the bearing 1 becomes uniform. In the conventional bearing 100 (see FIG. 12) in which the second rolling element 30 is not provided, the amount of oil in the cage dividing portion 500s is larger than that in other portions. In the present embodiment (FIG. 1), the second rolling element 30 is provided in the cage dividing portion 5s, so that the lubricating oil is suppressed from concentrating on the cage dividing portion 5s. Therefore, the amount of lubricating oil supplied to the bearing 1 (required supply amount) can be reduced, and the friction of the bearing 1 (the dragging loss of the lubricating oil) can be reduced.

  In the present embodiment, the case where the rolling elements 3 and the second rolling elements 30 are needle-shaped (needle-shaped) rollers has been described as an example, but the shapes of the rolling elements 3 and 30 are not limited thereto. Any roller used for the rolling bearing 1 can be used as the rolling element 3 and the second rolling element 30. In addition, the cage 5 of this embodiment is divided into two cage components 51 and 52. However, instead of this, the present embodiment is implemented even if the cage 5 is divided into three or more cage components. The configuration of the bearing 1 in the form can be applied. Although the length L1 of the second rolling element 30 in the axial direction is equal to the length of the rolling element 3 in the axial direction, the length is not limited to this. For example, the length L1 of the second rolling element 30 in the axial direction may be shorter than the length of the rolling element 3 in the axial direction. In this case, the mass of the second rolling element 30 can be made smaller than the mass of the rolling element 3.

(Second Embodiment)
A second embodiment will be described with reference to FIG. In the second embodiment, only differences from the first embodiment will be described.

  In the said 1st Embodiment, although the number of the 2nd rolling elements 30 arrange | positioned at the holder | retainer division | segmentation part 5s was one per place, it replaced with this, and the cage | basket division | segmentation part 5s of one place, A plurality of second rolling elements (see reference numeral 31 in FIG. 7) formed smaller than the rolling elements 3 can be arranged in the axial direction. In this case, the mass of the second rolling element 31 can be made small, and the durability of the cage 5 can be improved.

  FIG. 7 is a partial cross-sectional view in the circumferential direction of the bearing according to the present embodiment. In the present embodiment, two second rolling elements 31 (second rolling elements 31a and 31b) are arranged in the holding portion 54 formed in the cage dividing portion 5s. Similar to the second rolling element 30 of the first embodiment, the second rolling element 31 is a thin cylindrical needle-like (needle-like) roller, and is formed of the same material as the rolling element 3. Yes. The two second rolling elements 31 are arranged in series in the axial direction so that the direction of the axis (rolling center) of the second rolling element 31 is parallel to the axial direction of the bearing 1. The second rolling elements 31a and 31b of the present embodiment are formed in the same shape and size.

  The outer diameter D2 of the second rolling element 31 is the same as the outer diameter of the second rolling element 30 of the first embodiment. The length L2 in the axial direction of the second rolling element 31 is, for example, about half of the length L1 in the axial direction of the second rolling element 30 of the first embodiment.

  By making the 2nd rolling element 31 arrange | positioned in the holding | maintenance part 54 into two or more, the lifetime of the holder | retainer 5 can be improved so that it may demonstrate below. In the case where the cage 5 is divided, the end portion in the circumferential direction of the cage 5 (in the vicinity of the cage divided portion 5s) is likely to be deformed such as torsion and deflection as compared with other portions. In order to suppress the deformation, by reducing the mass of each second rolling element 31, the kinetic energy of the second rolling element 31 is reduced, and the aggressiveness of the second rolling element 31 against the cage 5 is reduced. It is effective to reduce. In this embodiment, the 2nd rolling element 31 arrange | positioned at the holding | maintenance part 54 is made into multiple, and the mass of each 2nd rolling element 31 shall be small. As a result, while maintaining the effect of reducing the surface pressure of the rolling elements 3 disposed near the circumferential ends of the cage components 51 and 52, one second rolling member is provided as in the first embodiment. Compared with the case where the moving body 30 receives a radial load, the aggression of the second rolling element 31 against the cage 5 can be reduced, and deformation of the cage 5 can be suppressed. As a result, the durability of the cage 5 can be improved.

  By reducing the aggressiveness of the second rolling element 31 against the cage 5, it is possible to reduce the holding force (strength) of the cage 5 required to hold the second rolling element 31 in the holding portion 54. It becomes. That is, the required strength of the cage 5 can be reduced. For example, when the number of the second rolling elements 30 arranged in one holding part 54 is one as in the first embodiment, it is necessary to make the cage 5 made of steel. In the present embodiment in which a plurality of second rolling elements 31 having a small mass are arranged in the holding portion 54, the cage 5 formed of a material having lower strength or lighter weight (low specific gravity) than steel, for example, a resin holding The vessel 5 can be employed. In this case, the collision sound when the cage components 51 and 52 collide with each other is reduced, and the noise of the bearing 1 can be reduced. Alternatively, without changing the material of the cage 5, the cage 5 can be made lighter while being made of steel.

  In the present embodiment, there are two second rolling elements 31 arranged in one cage dividing portion 5s, but the present invention is not limited to this. Three or more second rolling elements 31 may be arranged in one cage dividing portion 5s. In this case, the length L2 in the axial direction of the second rolling element 31 is adjusted in accordance with the number of the second rolling elements 31 arranged in one cage dividing portion 5s.

(Third embodiment)
The third embodiment will be described with reference to FIG. In the third embodiment, only differences from the above embodiments will be described.

  In the second embodiment (FIG. 7), the plurality of second rolling elements 31 are arranged in series in the axial direction on the holding portion 54. In this case, it is not desirable for the second rolling element 31 to move in the axial direction. For example, when the second rolling element 31 moves in the axial direction, the second rolling elements 31 come into contact with each other and dragging occurs, or the surface pressure distribution of the second rolling element 31 with respect to the radial load becomes uneven. As a result, noise increases and wear is promoted.

  In the cage 5 of the present embodiment, as shown in FIG. 8, a restriction that restricts movement of the second rolling elements 31 a and 31 b in the axial direction between two adjacent second rolling elements 31 a and 31 b. A portion 56 is provided. The restricting portion 56 is provided at the central portion in the axial direction at the circumferential end of the cage 5. The restricting portion 56 is circumferentially disposed in the space between the adjacent second rolling elements 31a and 31b so as to be able to come into contact with the axial ends of the second rolling elements 31a and 31b facing each other. It is formed in a protruding convex shape. By providing the restricting portion 56, the holding portion 54 is formed with a holding portion 54a that holds the second rolling element 31a and a holding portion 54b that holds the second rolling element 31b.

  As described above, the second rolling elements 31a and 31b are held by the corresponding holding portions 54a and 54b, so that the second rolling elements 31a and 31b are securely held, and the second rolling elements 31a and 31b are retained. The movement in the axial direction is restricted. Therefore, the contact of the second rolling elements 31a and 31b is suppressed, and the surface pressure distribution in the second rolling elements 31a and 31b becomes uniform. As a result, noise and wear of the second rolling elements 31a and 31b are reduced. Moreover, the intensity | strength of the edge part of the circumferential direction of the holder | retainer 5 improves by providing the control part 56. FIG.

(Fourth embodiment)
A fourth embodiment will be described with reference to FIG. In the fourth embodiment, only differences from the above embodiments will be described.

  In the second embodiment and the third embodiment, the plurality of second rolling elements 31 are arranged side by side along the axial direction. In the present embodiment, instead of this, a plurality of second rolling elements (see reference numeral 32 in FIG. 9) are arranged side by side in the radial direction. As a result, the mass of the second rolling element 32 is reduced, the aggression to the cage 5 is reduced, and the followability of the rolling surface (see reference numeral 32r in FIG. 9) to the raceway surfaces 2c and 2d is improved. Can be improved.

  FIG. 9 is a partial cross-sectional view in the radial direction of the bearing 1 according to the present embodiment. As shown in FIG. 9, in the bearing 1 of the present embodiment, a plurality of second rolling elements 32 are provided in the holding portion 54 formed between the first cage constituting portion 51 and the second cage constituting portion 52. They are arranged along the radial direction. The second rolling element 32 is a thin cylindrical needle-like (needle-like) roller similar to the rolling element 3 and is formed of the same material as the rolling element 3. In the example shown in FIG. 9, two second rolling elements 32 a and 32 b are arranged in the holding portion 54. The second rolling elements 32a and 32b are arranged such that the second rolling element 32a is positioned relatively radially inside (close to the central axis of the rotation shaft 2a). The sum of the outer diameters of the second rolling elements 32 a and 32 b is made equal to the outer diameter of the rolling element 3. The outer diameters of the second rolling elements 32 a and 32 b are half of the outer diameter of the rolling element 3. As a result, the second rolling elements 32a and 32b are arranged in series in the radial direction in a state where the second rolling element 32a is in contact with the inner raceway surface 2c and the second rolling element 32b is in contact with the outer raceway surface 2d. Thus, it can roll in the circumferential direction in a state of receiving a radial load.

  A holding groove 55a for holding the second rolling element 32a and a holding groove 55b for holding the second rolling element 32b are provided at the circumferential ends of the cage components 51 and 52, respectively. Since the second rolling elements 32a and 32b are respectively held by the holding grooves 55a and 55b, the occurrence of relative displacement in the circumferential direction between the second rolling element 32a and the second rolling element 32b is suppressed. ing.

  According to the present embodiment, the plurality of second rolling elements 32 are arranged in the radial direction between the first cage component 51 and the second cage component 52. Thereby, the mass of the one 2nd rolling element 32 can be made small, and the aggression property with respect to the holder | retainer 5 of the 2nd rolling element 32 can be reduced. Therefore, the durability of the cage 5 can be improved, or the required strength of the cage 5 can be reduced. Further, since the mass of the second rolling element 32 is reduced, the followability of the rolling surface 32r of the second rolling element 32 to the raceway surfaces 2c and 2d is improved, and wear and noise are reduced. In the present embodiment, since the outer diameter of the second rolling element 32 can be made small, the volume of the holding portion 54 that holds the second rolling element 32 can be made small. Thereby, an edge part can be formed in the shape which raises the intensity | strength of the edge part of the circumferential direction in the holder | retainer structure part 51,52.

  In addition, in this embodiment, although the 2nd rolling element 32 arrange | positioned at the holding part 54 of one place was two, it is not limited to this. Three or more second rolling elements 32 may be arranged in one holding portion 54. In this case, the outer diameter of the second rolling element 32 is adjusted according to the number of the second rolling elements 32 arranged in one holding portion 54.

(First modification of each of the above embodiments)
A first modification of the first to fourth embodiments will be described.

  In each said embodiment, although the material of the 2nd rolling elements 30,31,32 was made into the same material as the rolling element 3, it replaces with this and the material of the 2nd rolling elements 30,31,32 is used. Compared to the material of the rolling element 3, the material can have a low specific gravity. Thereby, the mass of the 2nd rolling elements 30,31,32 can be reduced, and the aggression property with respect to the holder | retainer 5 of the 2nd rolling elements 30,31,32 can be reduced. For example, when the rolling element 3 is made of steel, the second rolling elements 30, 31, 32 can be made of ceramic.

(Second modification of the above embodiments)
A second modification of the first to fourth embodiments will be described.

  In each of the above embodiments, there is no restriction on the circumferential movement of the cage 5 relative to the outer ring 2b. That is, the cage 5 is provided to be rotatable in the circumferential direction with respect to the outer ring 2b fixed to the housing. Instead, in this modification, the cage 5 is not moved relative to the outer ring 2b in the circumferential direction. More specifically, the cage 5 is fixed to the outer ring 2b. Since the relative movement in the circumferential direction between the outer ring 2b and the cage 5 does not occur, the friction loss between the outer ring 2b and the cage 5 can be reduced.

  FIG. 10 is a schematic cross-sectional view in the radial direction of the bearing 1 according to this modification. FIG. 10 shows the bearing 1 in the case where one second rolling element 30 is arranged in each cage dividing portion 5 s between the first cage component 51 and the second cage component 52. Has been. As shown in FIG. 10, convex-shaped protrusions 5 d that protrude in the radial direction are formed on the outer peripheral surfaces of the cage constituting portions 51 and 52. On the other hand, a concave groove 2f corresponding to the protrusion 5d is formed at the end in the circumferential direction (outer ring split portion 2s) on the inner peripheral surfaces of the outer ring constituent portions 21b and 22b. The protrusions 5d of the cage constituting portions 51 and 52 are fitted in the groove portions 2f of the outer ring constituting portions 21b and 22b. Thus, the outer ring 2b and the cage 5 are fixed so that relative movement of the cage 5 in the circumferential direction with respect to the outer ring 2b does not occur.

  When the rotating shaft 2a rotates, the rolling elements 3 roll (rotate) on the inner raceway surface 2c and the outer raceway surface 2d while being held by the cage 5, and the second rolling element 30 is rotated. Rolls (spins) on the inner raceway surface 2c and the outer raceway surface 2d while being held by the holding portion 54. Thereby, the bearing 1 supports the rotating shaft 2a rotatably with respect to the outer ring 2b. At this time, since the circumferential movement of the cage 5 relative to the outer ring 2b does not occur, in addition to the effects of the above embodiments, the friction loss between the outer ring 2b and the cage 5 is reduced. The effect of making it possible can be produced. Further, the circumferential ends of the rolling element 3, the second rolling element 30, or the cage constituting parts 51 and 52 do not pass through the outer ring dividing part 2s. For this reason, the effect of reducing the noise and rolling friction of the bearing 1 and the effect of improving the durability of the bearing 1 can be achieved.

(Third Modification of Each Embodiment)
With reference to FIG. 11, the 3rd modification of the said 1st Embodiment to 4th Embodiment is demonstrated.

  In the second modified example, the cage 5 is fixed to the outer ring 2b, and the cage 5 is not rotated in the circumferential direction with respect to the outer ring 2b. Instead of this, the circumferential movement of the cage 5 may be restricted so that the circumferential relative movement of the cage 5 with respect to the outer ring 2b is within a predetermined range. For example, this is a case where the range in which the rotating shaft 2a is swung relative to the outer ring 2b is limited to a predetermined range. In this case, from the viewpoint of suppressing noise or the like of the bearing 1, the range of relative movement in the circumferential direction of the cage 5 with respect to the outer ring 2b is regulated so that the circumferential range of movement of the cage 5 is a desired range. be able to.

  In the present modification, the circumferential movement range of the cage 5 is restricted so that the circumferential ends of the cage components 51 and 52 do not pass through the outer ring split portion 2s. As a result, noise, rotational resistance, etc. can be generated in a state where collision between the circumferential ends of the cage components 51 and 52 and the circumferential ends of the outer ring components 21b and 22b (outer ring dividing portion 2s) does not occur. Can be reduced.

  FIG. 11 is a schematic sectional view in the radial direction of the bearing 1 according to this modification. As shown in FIG. 11, the groove 2 f of this modification has a predetermined length A in the circumferential direction. The predetermined length A is a length corresponding to the moving range of the cage 5 when the rotary shaft 2a is swung relative to the outer ring 2b in the circumferential direction. When the cage 5 moves (revolves) in the circumferential direction, the protrusion 5d moves in the circumferential direction in the groove 2f. The protrusion 5d abuts on the circumferential end of the groove 2f, whereby the circumferential movement of the cage 5 is restricted. The restricting means of this modification is configured by the groove 2f and the protrusion 5d.

  Even if the cage 5 moves in the circumferential direction within the range of the predetermined length A, the protrusion 5d is provided at a position where the circumferential ends of the cage components 51 and 52 do not pass through the outer ring dividing portion 2s. That is, when the protrusion 5d moves from the position where the protrusion 5d is in contact with one end in the circumferential direction of the groove 2f to the position where it is in contact with the other end, the circumferential ends of the cage components 51 and 52 are moved. Is provided at a position so as not to pass through the outer ring dividing portion 2s. Accordingly, the cage is configured so that the circumferential ends of the cage components 51 and 52 do not pass through the outer ring dividing portion 2s without preventing the rotation shaft 2a from swinging and rotating relative to the outer ring 2b. The movement range of the components 51 and 52 can be restricted.

  By preventing collision between the circumferential ends of the cage components 51 and 52 and the circumferential ends of the outer ring components 21b and 22b (outer ring dividing portion 2s), noise and rotational resistance of the bearing 1 are reduced. Or the durability of the bearing 1 can be improved.

It is a schematic sectional drawing of the radial direction of 1st Embodiment of the rolling bearing of this invention. It is a perspective view of 1st Embodiment of the rolling bearing of this invention. It is a fragmentary sectional view of the axial direction of 1st Embodiment of the rolling bearing of this invention. It is a fragmentary sectional view of the circumferential direction of 1st Embodiment of the rolling bearing of this invention. It is an enlarged view near the cage | basket | carrier division | segmentation part of 1st Embodiment of the rolling bearing of this invention. It is a figure for demonstrating the effect of 1st Embodiment of the rolling bearing of this invention. It is a fragmentary sectional view of the circumferential direction of 2nd Embodiment of the rolling bearing of this invention. It is a fragmentary sectional view of the circumferential direction of 3rd Embodiment of the rolling bearing of this invention. It is a fragmentary sectional view of the radial direction of 4th Embodiment of the rolling bearing of this invention. It is a schematic sectional drawing of the radial direction of the 2nd modification of each embodiment of the rolling bearing of this invention. It is a schematic sectional drawing of the radial direction of the 3rd modification of each embodiment of the rolling bearing of this invention. It is a schematic sectional drawing of the radial direction which shows an example of the rolling bearing in which the split type cage was used.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bearing 2 Race ring 2a Rotating shaft 2b Outer ring 2c Inner raceway surface 2d Outer raceway surface 2e Collar 2f Groove 2s Outer ring division part 3 Rolling body 3e End rolling element 3r Rolling surface 4 Rolling part 5 Cage 5a Annular part 5b Separate Part 5c Rolling body holding part 5d Protrusion 5s Cage dividing part 21b First outer ring constituting part 22b Second outer ring constituting part 30, 31, 32 Second rolling element 30r Rolling surface 51 First retainer constituting part 52 Second holding Cage constituting part 54 Holding part 55 Holding groove 56 Restricting part 100 Bearing 200 Bearing ring 200a Rotating shaft 200b Outer ring 300 Rolling body 300a End rolling element 500 Cage 501 First cage construction part 502 Second cage construction part

Claims (8)

An outer ring, a plurality of first rolling elements disposed along a circumferential direction of the outer ring in a space between the outer ring and a rotation shaft disposed inside the outer ring, and the plurality of first rolling elements. A retainer for holding a moving body, and the retainer is composed of a plurality of retainer components disposed at different positions along the circumferential direction, and the circumferential ends of the retainer component are A rolling bearing in which the first rolling element is held at a predetermined interval along the circumferential direction by a rolling element holding part disposed between the circumferential direction,
A rolling bearing, wherein a second rolling element is disposed between the cage constituent parts adjacent in the circumferential direction among the plurality of cage constituent parts. The rolling bearing according to claim 1,
A concave portion having a shape corresponding to the shape of the second rolling element is provided at an end in the circumferential direction of the cage component, and the second rolling element is held by the concave portion. Rolling bearing characterized by In the rolling bearing according to claim 1 or 2,
One of the second rolling elements is disposed between the adjacent cage components,
The rolling bearing characterized in that the second rolling element has the same diameter as the first rolling element and has a smaller mass than the mass of each of the first rolling elements. In the rolling bearing according to claim 1 or 2,
A plurality of the second rolling elements are arranged between the adjacent cage constituent parts along the axial direction of the outer ring, respectively.
The rolling bearing characterized in that the second rolling element has the same diameter as the first rolling element and has a smaller mass than the mass of each of the first rolling elements. The rolling bearing according to claim 4,
The end portions in the circumferential direction of the cage constituting portion are provided so that the end portions in the axial direction of the second rolling elements facing each other can come into contact with each other, and the second rolling elements are A rolling bearing characterized in that a restricting portion for restricting movement in the axial direction is provided. In the rolling bearing according to claim 1 or 2,
Two of the second rolling elements are arranged along the radial direction of the outer ring between the adjacent cage constituent parts,
The rolling bearing according to claim 1, wherein the second rolling element has a diameter that is half the diameter of the first rolling element and has a smaller mass than the mass of each of the first rolling elements. In the rolling bearing according to any one of claims 1 to 6,
The rolling bearing, wherein the outer ring and the cage are fixed so that the circumferential movement of the cage with respect to the outer ring does not occur. In the rolling bearing according to any one of claims 1 to 6,
The outer ring is divided into a plurality of outer ring components disposed at different positions along the circumferential direction,
The rolling bearing includes a restricting means for restricting a range of relative movement of the retainer in the circumferential direction with respect to the outer ring so that an end portion in the circumferential direction of the retainer constituting portion does not pass through a split portion of the outer ring. A rolling bearing characterized by comprising.

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