JP6550711B2 - Crown type cage for rolling bearing - Google Patents

Description

The present invention relates to a crown type cage for a rolling bearing.

  In rolling bearings, cages are used in many types. The main role of the cage is to make the rotating rolling elements revolve equidistantly with respect to the bearing and maintain the rigidity and rotational accuracy of the bearing in a high state.

  The cage is generally disposed between the rolling element, the inner ring, and the outer ring with a fixed gap. When the amount of movement in the radial direction of the cage is regulated by the inner ring or the outer ring, it is classified as an inner ring guide cage or outer ring guide cage, and when it is regulated by a rolling element, it is classified as a rolling element guide cage. .

  In order to maintain the even distribution of the rolling elements, contact occurs between the cage and the rolling elements during bearing rotation. In particular, in the case of a rolling element guide retainer, the movement of the retainer usually depends on the rolling element, so that the friction generated by the contact between the retainer and the rolling element increases.

  Friction generated between the rolling elements and the cage pocket causes heat generation, wear, and rotation failure (rambling) of the cage. Heat generation and wear cause deterioration of the bearing (life reduction), and rotation failure of the cage (runaway) generates poor rotation accuracy and abnormal noise. Therefore, such reduction of friction in rolling bearings is a problem to be solved. It has become one.

  Patent Document 1 discloses a cage having a Gothic arch-shaped composite curved surface in which a circumferential side surface of a pillar portion is formed by connecting an outer diameter side concave curved surface portion and an inner diameter side concave curved surface. Thus, regardless of the displacement of the rollers in the pocket, the rolling surfaces of the rollers and the radial end edges of the circumferential side surfaces of the column portions do not contact (per edge).

JP 2007-278406 A

  However, in the cage described in Patent Document 1, since the circumferential side surface of the column portion is formed by connecting two concave arcs, when the rolling body revolves, the rolling body and the circumferential side surface There is a problem in that the contact comes into contact with two surfaces and the friction increases.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a crown type retainer for a rolling bearing which can reduce the friction generated between the rolling element and the pocket portion.

The above object of the present invention is achieved by the following constitution.
(1) A plurality of pillars arranged at predetermined intervals in the circumferential direction,
Pocket portions formed between adjacent ones of the pillars for holding the rolling elements in a freely rolling manner;
An annular portion connected to one axial end of the plurality of columns;
A crown-type cage for a rolling bearing comprising
The pocket portion includes a first circumferential side surface of one of the adjacent pillar portions, a second circumferential side surface of the other pillar portion, and an axial side surface of the annular portion. , has a,
The first circumferential side surface is composed of a first partial spherical surface forming a part of a spherical surface and a first partial cylindrical portion forming a part of a cylindrical body,
The second circumferential side surface is constituted of a second partial spherical surface forming a part of a spherical surface and a second partial tubular part forming a part of a cylindrical body,
The axial side surface of the annular portion has a planar shape,
In a cross section perpendicular to the axial direction, including a first center of the first partial sphere and a second center of the second partial sphere, and
The first circumferential side surface is a cross section of the first partial spherical surface, and is a first arc having the first center, and the first partial cylindrical portion connected to the first arc and linearly extending. And a first straight portion, which is a cross section of
Said second circumferential sides, a cross-sectional of the second partial spherical surface, and a second arc having a second center, extend linearly connected with the second arc, said second portion cylindrical portion And a second straight part, which is a cross section of
The radius of the first arc and the radius of the second arc are larger than the radius of the rolling element,
The first center and the second center is an identical axial position and radial position, Ri is unequal der circumferential position,
The first center is more than an intermediate line M extending through a circumferential intermediate portion between the first circumferential side surface and the second circumferential side surface and the center of the rolling bearing crown cage. It is located on the side of the second circumferential side, and the second center is located on the side of the first circumferential side with respect to the middle line M,
The first straight portion and the second straight portion extend substantially in parallel with the intermediate line M or extend away from the intermediate line M as they go radially outward.
The radial positions of the first center and the second center correspond to the pitch circle diameter of the rolling element in a state in which the crown retainer for a rolling bearing is not moved relative to the rolling element in the radial direction. ,
The connection position of the first arc and the first straight portion, and the connection position of the second arc and the second straight portion are respectively the first circumferential side surface and the second circumferential direction. At a radially intermediate position of the side, which is identical to the pitch circle diameter,
Crown type cage for rolling bearings.
( 2 ) The crown type retainer for a rolling bearing according to (1) , wherein the first arc and the second arc have the same radius.
( 3 ) The crown type retainer for a rolling bearing according to (1) , wherein the first arc and the second arc have different radii.

According to the crown type cage for rolling bearing of the present invention, the first circumferential side surface forming the pocket portion has the first arc having the first center and the first straight portion, and the second circumference direction side, a second arc that having a second center, and a second straight portion, the first arc and second arc radius is greater than the radius of the rolling element, the first center and the second center The axial position and the radial position are the same, and the circumferential position is the same. Therefore, when the cage relatively moves in the radial direction with respect to the rolling element, the contact between the cage and the rolling element becomes a surface contact, so the radial direction edge of the circumferential side surface of the rolling element and the column portion It is possible to avoid that the part collides with the edge.
Also, the first arc included in the first circumferential side is an arc belonging to a single partial sphere, and the second arc included in the second circumferential side is an arc belonging to a single partial sphere because, when the relative movement in the circumferential direction relative to the rolling element cage, the rolling elements are in contact with a single partial spherical surface and one point of the cage.
Thus, since the contact area is reduced, it is possible to reduce the sliding friction generated between the rolling element and the cage. Therefore, the crown type cage for rolling bearings of the present invention is suitable for a rolling element guide type cage having a large contact friction between the rolling elements and the cage.

It is a perspective view of the holder for rolling bearings concerning a 1st embodiment of the present invention. It is sectional drawing which looked at the cage for rolling bearings of FIG. 1 from the axial direction. It is sectional drawing which looked at the cage for rolling bearings of FIG. 1 from the radial direction. It is sectional drawing which shows the state which the cage | basket and the ball moved relatively to the radial direction. It is sectional drawing which shows the state which the ball | bowl moved to the radial inside. It is sectional drawing which shows the state which the ball | bowl moved to the radial direction outer side. (A) is a figure which shows the 1st and 2nd center and 1st and 2nd radius of (b)-(d) of 1st Embodiment of a modification. It is sectional drawing which looked at the holder for rolling bearings concerning 2nd Embodiment from the axial direction. It is sectional drawing which looked at the holder for rolling bearings concerning 3rd Embodiment from the axial direction. It is sectional drawing which looked at the cage for rolling bearings concerning the modification from the axial direction.

  Hereinafter, a rolling bearing retainer according to an embodiment of the present invention will be described using the drawings.

First Embodiment
As shown in FIG. 1, the rolling bearing retainer 1 of the present embodiment (hereinafter simply referred to as a retainer) includes a plurality of column portions 10 arranged at predetermined intervals in the circumferential direction, and adjacent column portions A pocket portion 20 formed between 10 and rollingly holding balls 3 (see FIGS. 2 and 3) as rolling elements, and a ring portion connected to one axial end portion of the plurality of column portions 10 30 is a ball guide type crown-shaped cage.

  As shown in FIGS. 2 and 3, the pocket portion 20 includes the first circumferential side surface 11 a of one column portion 10 and the second circumferential side surface of the other column portion 10 among the adjacent column portions 10. 11b and the axial side surface 31 of the annular portion 30.

  The first and second circumferential side surfaces 11a and 11b are spherical shapes formed of first and second arcs 12a and 12b having first and second centers Oa and Ob and first and second radii Ra and Rb, respectively. It is. That is, the first and second circumferential side surfaces 11a and 11b are formed in a so-called gothic arch shape.

  The first and second centers Oa and Ob have the same axial position (position perpendicular to the paper surface in FIG. 2; position in the left-right direction in FIG. 3), and circumferential position (clockwise position in FIG. 2). The vertical position in FIG. 3 is the same, and the radial position (the vertical position in FIG. 2; the vertical position in FIG. 3) is the same. The first and second radii Ra and Rb are set equal to each other (Ra = Rb) and larger than the radius of the ball 3.

  By shifting the positions of the first and second centers Oa and Ob to appropriate values and setting the first and second radii Ra and Rb to appropriate values, the cage 1 and the ball 3 are rotated as shown in FIG. Even when they move relative to each other in the radial direction, the contact between the cage 1 and the balls 3 can be made per surface. Assuming that the first and second centers Oa and O are at the same position, and the first and second circumferential side surfaces 11a and 11b are arcs of a single center, the cage 1 and the cage 1 can be used in any dimensional relationship. The contact with the ball 3 is per edge. That is, the radial direction edge part (edge part) of the pocket part 20 and the ball 3 contact, and it becomes a big factor which causes the defect and abnormality by the friction increase of a contact part. Since the cage 1 of the present embodiment can avoid such edge contact, it is possible to reduce the friction of the contact portion.

The above-mentioned appropriate value is a numerical value which satisfies the following conditions. In FIG. 5, the cage 1 moves radially outward, and the first circumferential side surface 11a of the cage 1 contacts the ball 3 at e, and the second circumferential side surface 11b and the ball 3 The state of contact at f is shown. In addition, the radially inner edge of the first circumferential side surface 11a is denoted by a, the radially outer edge is denoted by b, and the radially inner edge of the second circumferential side surface 11b is denoted by c. The radially outer edge is indicated by d. In FIG. 5, the Y-axis direction is the same direction as an intermediate line M radially extending in the circumferential direction intermediate portion of the first and second circumferential side surfaces 11a and 11b, and the X-axis direction is a Y-axis direction and a bearing It is a direction perpendicular to the rotation axis direction. Further, Y-axis is an axis passing through the center O ₁ of the bearing center O and the cage 1, X-axis is an axis passing through the center O ₁ of the cage 1. At this time, the coordinates of Oa, Ob, a to f are (X _Oa , Y _Oa ), (X _Ob , Y _{O b} ), (X _a , Y _a ), (X _b , Y _b ), (X _c ) , Y _c ), (X _d , Y _d ), (X _e , Y _e ), (X _f , Y _f ), the diameter of the ball 3 is W, and the intermediate line between the first and second centers Oa, Ob The amounts of deviation in the X-axis direction from M (Y-axis) are La and Lb, and the pitch circle diameter of the ball 3 is PCD.

At this time, the contact point e satisfies (La−Ra) <X _e <X _a and Y _a <Y _e <Y _b . X _e and Y _e are expressed as follows.

Similarly, contact point f _{is, X c <X f <(} Rb-Lb), and satisfies the _{Y c <Y f <Y d} . X _f and Y _f are expressed as follows.

In FIG. 6, the cage 1 moves inward in the radial direction, and the first circumferential side surface 11a of the cage 1 contacts the ball 3 at g, and the second circumferential side surface 11b and the ball 3 A contact state is indicated by h. Here, each coordinate of g and _{h, (X} g, Y _g), a _{(X h, Y} h).

At this time, the contact point g satisfies _{(La-Ra) <X g} <X b, and _{Y a <Y g <Y b} . _Xg and _Yg are expressed as follows.

Similarly, the contact point h satisfies X _d <X _h <(Rb−Lb) and Y _c <Y _h <Y _d . X _h and Y _h are expressed as follows.

  Thus, at the contact points e to h, the contact conditions between the first and second circumferential side surfaces 11 a and 11 b of the cage 1 and the ball 3 are all satisfied.

  Moreover, even if the said ball | bowl 3 and the holder | retainer 1 contact in the circumferential direction by revolution of the ball | bowl 3, the 1st and 2nd circumferential direction side surfaces 11a and 11b are the revolution directions ( (Circumferential direction) consists of a single first and second circular arc 12a, 12b, so that the ball 3 and the cage 1 can be brought into contact at one point, as in a conventional cage.

  As in the present embodiment, it is preferable that the radial positions of the first and second centers Oa and Ob be the same for the degree of freedom of the bearing rotational axis direction, and the first and second arcs 12a, It is preferable that the first and second radiuses Ra and Rb of 12b be the same (see FIG. 7A). However, in order to intentionally constrain the cage 1 for the purpose of restraint rampage suppression or the like, the radial positions of the first and second centers Oa, Ob and the first and second radii Ra, Rb Of these, one or both may be different values. For example, as shown in FIG. 7B, the radial positions of the first and second centers Oa and Ob may be different, and the first and second radii Ra and Rb may be the same. Further, as shown in FIG. 7C, the radial positions of the first and second centers Oa and Ob may be the same, and the first and second radii Ra and Rb may be different. Further, as shown in FIG. 7D, the radial positions of the first and second centers Oa and Ob and the first and second radii Ra and Rb may be different.

  The radial movement amount of the cage 1 includes the coordinates of the first and second centers Oa and Ob, the first and second radii Ra and Rb of the first and second arcs 12a and 12b, the diameter W of the ball 3, And the pitch circle diameter PCD of the ball 3 is determined. These values are numerical values that can be changed depending on the application of the bearing, but the same effects can be exhibited as long as the above-described edge contact is an avoidable value, regardless of the values set.

  Returning to FIGS. 1 and 3, the axial side surface 31 of the annular portion 30 constituting the pocket portion 20 has a planar shape. Therefore, even when the cage 1 and the ball 3 relatively move in the axial direction, the ball 3 contacts with the axial side 31 at one point, so that the friction at the time of axial movement amount restriction can be reduced. Further, since the position of the axial side surface 31 can be designed freely to some extent, the amount of movement of the cage 1 can be set to some extent freely.

Second Embodiment
Next, a rolling bearing retainer 1 according to a second embodiment of the present invention will be described with reference to FIG. In the cage 1 of the present embodiment, the first and second circumferential side surfaces 11a and 11b have first and second arcs 12a and 12b having first and second centers Oa and Ob, and the first and second circular arcs 12a and 12b. It comprises a first and a second straight portion 13a, 13b having a planar shape, connected to the radially outer end of the arcs 12a, 12b. Of the first and second circumferential side surfaces 11a and 11b, approximately half of the radially inner side is the first and second arcs 12a and 12b, and approximately half of the radially outer side is the first and second straight portions. 13a and 13b. Further, the first and second straight portions 13a and 13b of the present embodiment are formed to be substantially parallel to the intermediate line M. Note that the first and second straight portions 13a and 13b may be shaped so as to be separated from the intermediate line M in the circumferential direction toward the radially outer side.

  By configuring in this manner, the restriction of the amount of movement of the cage 1 in the radial direction is limited only to that by the first and second arcs 12a and 12b, so the randomness of the contact position between the ball 3 and the cage 1 is It becomes possible to decrease and to stabilize the movement of the cage 1. In addition, when the cage 1 expands due to centrifugal force during operation, the diameter of the cage 1 increases as the gap of the pocket portion 20 in the ball 3 revolution direction (circumferential direction) increases, so that the cage 1 is relatively held. It is possible to suppress or reduce the increase in the amount of radial movement of the vessel 1.

Third Embodiment
Next, a rolling bearing retainer 1 according to a third embodiment of the present invention will be described with reference to FIG. In the cage 1 of the present embodiment, the first and second circumferential side surfaces 11a and 11b have first and second arcs 12a and 12b having first and second centers Oa and Ob, and the first and second circular arcs 12a and 12b. It comprises first and second straight portions 13a, 13b having a planar shape, connected to radially inner end portions of the arcs 12a, 12b. Of the first and second circumferential side surfaces 11a and 11b, approximately half of the radially outer side is the first and second arcs 12a and 12b, and approximately half of the radially inner side is the first and second straight portions. 13a and 13b. Further, the first and second straight portions 13a and 13b of the present embodiment are formed to be substantially parallel to the intermediate line M. The first and second straight portions 13a and 13b may be shaped so as to be separated from the intermediate line M in the circumferential direction as they extend inward in the radial direction.

  By configuring in this manner, the restriction of the amount of movement of the cage 1 in the radial direction is limited only to that by the first and second arcs 12a and 12b, so the randomness of the contact position between the ball 3 and the cage 1 is It becomes possible to decrease and to stabilize the movement of the cage 1. In the present embodiment, since the amount of movement of the cage 1 can be increased by increasing the centrifugal force, the occurrence of interference between the first and second arcs 12a, 12b and the ball 3 due to the expansion of the cage 1 can be avoided. At the same time, it is possible to set the initial value of the radial movement amount of the cage 1 as small as possible.

  The present invention is not limited to the above-described embodiment, and appropriate modifications, improvements, and the like can be made.

  For example, in the above-described embodiment, the configuration in which the present invention is applied to the so-called crown-shaped cage 1 having only one annular portion 30 is described. However, the so-called cage-shaped cage having a pair of annular portions is used. Is also applicable. In FIG. 10, the cage | basket shaped holder 1 provided with 1st and 2nd annular ring part 30a, 30b respectively connected with the axial direction both ends of several pillar part 10 is shown. In the cage 1, since the axial side surfaces 31a and 31b of the first and second annular portions 30a and 30b constituting the pocket portion 20 have a planar shape, the amount of axial movement of the cage 1 can be accurately performed. It becomes possible to set.

1 Retainer for rolling bearing 3 Ball (rolling element)
10 Column 11a First circumferential side surface 11b Second circumferential side surface 12a First arc 12b Second arc 13a First straight portion 13b Second straight portion 20 Pocket portion 30 Annular portion 30a First annular portion 30b First 2 annular parts 31, 31a, 31b axial direction side La X axial direction deviation M intermediate line Oa first center Ob second center PCD pitch circle diameter Ra first radius Rb second radius W ball diameter

Claims (3)

A plurality of pillars arranged at predetermined intervals in the circumferential direction;
Pocket portions formed between adjacent ones of the pillars for holding the rolling elements in a freely rolling manner;
An annular portion connected to one axial end of the plurality of columns;
A crown type cage for rolling bearings comprising:
The pocket portion includes a first circumferential side surface of one of the adjacent pillar portions, a second circumferential side surface of the other pillar portion, and an axial side surface of the annular portion. And have
The first circumferential side surface is composed of a first partial spherical surface forming a part of a spherical surface and a first partial cylindrical part forming a part of a cylindrical body,
The second circumferential side surface is composed of a second partial spherical surface forming a part of a spherical surface and a second partial cylindrical part forming a part of a cylindrical body,
The axial side surface of the annular part is a planar shape,
In a cross section perpendicular to the axial direction, including a first center of the first partial sphere and a second center of the second partial sphere, and
The first circumferential side surface is a cross section of the first partial spherical surface, and is a first arc having the first center, and the first partial cylindrical portion connected to the first arc and linearly extending. A first straight portion having a cross section of
Said second circumferential sides, a cross-sectional of the second partial spherical surface, and a second arc having a second center, extend linearly connected with the second arc, said second portion cylindrical portion A second straight portion having a cross section of
The radius of the first arc and the radius of the second arc are larger than the radius of the rolling element,
The first center and the second center is an identical axial position and radial position, Ri is unequal der circumferential position,
The first center is more than an intermediate line M extending through a circumferential intermediate portion between the first circumferential side surface and the second circumferential side surface and the center of the rolling bearing crown cage. It is located on the side of the second circumferential side, and the second center is located on the side of the first circumferential side with respect to the middle line M,
The first straight portion and the second straight portion extend substantially parallel to the intermediate line M or away from the intermediate line M toward the radially outer side,
The radial positions of the first center and the second center correspond to the pitch circle diameter of the rolling element in a state in which the crown retainer for a rolling bearing is not moved relative to the rolling element in the radial direction. ,
The connection position of the first arc and the first straight portion, and the connection position of the second arc and the second straight portion are respectively the first circumferential side surface and the second circumferential direction. At a radially intermediate position of the side, which is identical to the pitch circle diameter,
Crown type cage for rolling bearings. The crown retainer for a rolling bearing according to claim 1 , wherein the first arc and the second arc have the same radius. The crown retainer for a rolling bearing according to claim 1 , wherein the first arc and the second arc have different radii.

Images