Patent Description:
In the related art, various types of rolling bearings are known in which a retainer whose pockets accommodate rollers is integrated with an inner ring or an outer ring by retaining the inner ring or the outer ring.

For example, in a needle bearing described in Patent Literature <NUM>, a holding tab provided on a ring portion of a retainer is engaged with an inclined surface portion formed on an inner ring or an outer ring to prevent the retainer from falling off.

Further, in a cylindrical roller bearing described in Patent Literature <NUM>, a protrusion is provided on an axial side surface of a retainer, and the protrusion is engaged with a hole provided in an annular guide member disposed on a lateral side of the retainer, and thereby an inward flange of an outer ring is sandwiched between cylindrical rollers and the guide member, and the retainer is prevented from falling off from the outer ring.

Patent Literature <NUM> discloses a cylindrical roller bearing with an outer ring having the features of the preamble of claim <NUM>.

However, in Patent Literature <NUM>, since it is necessary to machine the inclined surface portion or the like on the inner ring, there is a problem that the manufacturing cost is increased. Further, in Patent Literature <NUM>, since the guide member is separately provided in order to prevent the retainer from falling off, there are problems that the number of components is increased, the manufacturing cost is increased, and the assembling workability is also reduced.

Further, as in Patent Literature <NUM>, in a case of a cylindrical roller bearing in which the cylindrical rollers directly roll on an outer circumferential surface of a shaft, it is required that the cylindrical rollers can be easily inserted into the retainer and that the cylindrical rollers are prevented from falling off from the retainer during transportation before assembly to the shaft.

The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a cylindrical roller bearing with an outer ring which can prevent a retainer from falling off from the outer ring with good assembly workability without increasing the number of components, and which takes into consideration insertion workability of cylindrical rollers and prevention of the cylindrical rollers from falling off from the retainer.

The above-described object of the present invention is achieved by the features of claim <NUM>.

According to the cylindrical roller bearing with an outer ring of the present invention, since the annular portion of the retainer on the other side in the axial direction is provided with the plurality of protrusion portions each having the engaging portion protruding farther radially outward with respect to the inner circumferential surface of the inward flange portion, the inward flange portion of the outer ring is sandwiched between the cylindrical rollers and the protrusion portions, and the retainer can be prevented from falling off from the outer ring without increasing the number of components with good assembly workability.

Further, on the side surface of the column portion of the retainer, the distance between the flat surface portions of the adjacent column portions is <NUM>% to <NUM>% of the roller diameter, the circumferential protrusion amount of the outer diameter-side retaining portion from the flat surface portion is <NUM>% to <NUM>% of the roller diameter, and the circumferential protrusion amount of the inner diameter-side retaining portion from the flat surface portion is <NUM>% to <NUM>% of the roller diameter, so that the insertion workability of the cylindrical rollers and the prevention of the cylindrical rollers from falling off from the retainer can be realized.

Hereinafter, a cylindrical roller bearing with an outer ring according to each embodiment of the present invention will be described in detail with reference to the drawings.

As illustrated in <FIG> and <FIG>, a cylindrical roller bearing <NUM> with an outer ring according to a first embodiment includes an outer ring <NUM>, a plurality of cylindrical rollers <NUM>, and a retainer <NUM>. The outer ring <NUM> is formed into an annular shape by pressing a metal plate such as a thin steel plate. The outer ring <NUM> includes a cylindrical portion <NUM> having an outer ring raceway surface <NUM> on an inner circumferential surface thereof, an outward flange portion <NUM> extending radially outward from an end portion on one side in an axial direction of the cylindrical portion <NUM>, and an inward flange portion <NUM> extending radially inward from an end portion on the other side in the axial direction of the cylindrical portion <NUM>.

The retainer <NUM> is made of resin, and as illustrated in <FIG>, includes a pair of annular portions <NUM>, <NUM> spaced apart in the axial direction, and a plurality of column portions <NUM> connecting the pair of annular portions <NUM>, <NUM> and arranged at intervals in a circumferential direction.

The plurality of cylindrical rollers <NUM> are held in a plurality of pockets <NUM> each of which is formed by adjacent column portions <NUM> and the pair of annular portions <NUM>, <NUM> of the retainer <NUM>, and are disposed to be rollable with respect to the outer ring raceway surface <NUM>.

As illustrated in <FIG>, on a circumferential side surface of the column portion <NUM> of the retainer <NUM>, a flat surface portion <NUM> in which the side surfaces of the adjacent column portions <NUM> forming the pocket <NUM> are parallel to each other, and an outer diameter-side retaining portion <NUM> and an inner diameter-side retaining portion <NUM> respectively protruding from the flat surface portion <NUM> in the circumferential direction on an outer diameter side and an inner diameter side are formed.

The flat surface portions <NUM> guide the cylindrical rollers <NUM> in the circumferential direction, and the outer diameter-side retaining portions <NUM> and the inner diameter-side retaining portions <NUM> prevent the cylindrical rollers <NUM> from falling out of the pockets <NUM>.

A distance L between the flat surface portions <NUM> of adjacent column portions <NUM> is <NUM>% to <NUM>% (<NUM>. 015D ≤ L ≤ <NUM>. 070D) of a roller diameter D, a circumferential protrusion amount S1 of the outer diameter-side retaining portion <NUM> from the flat surface portion <NUM> is <NUM>% to <NUM>% (<NUM>. 01D ≤ S1 ≤ <NUM>. 04D) of the roller diameter D, and a circumferential protrusion amount S2 of the inner diameter-side retaining portion <NUM> from the flat surface portion <NUM> is set to <NUM>% to <NUM>% (<NUM>. 04D ≤ S2 ≤ <NUM>. 10D) of the roller diameter D. The protrusion amount S1 of the outer diameter-side retaining portion <NUM> is smaller than the protrusion amount S2 of the inner diameter-side retaining portion <NUM> (S1 < S2).

Since an engagement margin between the outer diameter-side retaining portion <NUM> and the cylindrical roller <NUM> is set to be small due to the circumferential protrusion amount S1, the cylindrical roller <NUM> can be easily assembled into the retainer <NUM> without damaging the retainer <NUM> even when the cylindrical roller <NUM> is pushed into the pocket <NUM> of the retainer <NUM> from the outer diameter side. Further, since the outer ring <NUM> is disposed on the outer diameter side of the cylindrical rollers <NUM> held by the retainer <NUM>, the cylindrical rollers <NUM> do not fall off from the outer diameter side of the pockets <NUM> when the bearing is used. Therefore, the engagement margin on the outer diameter side can be set to be smaller than an engagement margin on the inner diameter side as long as, in an assembly process of the bearing, the retainer <NUM> into which the cylindrical rollers <NUM> are assembled can hold the cylindrical rollers <NUM> until the retainer <NUM> is inserted into the outer ring <NUM>.

Further, since the engagement margin on the inner diameter side between the inner diameter-side retaining portion <NUM> and the cylindrical roller <NUM> is set to be large due to the circumferential protrusion amount S2, the cylindrical rollers <NUM> can be prevented from falling off from the inner diameter side of the pocket <NUM> during transportation before assembly to the shaft or during an assembly process to the shaft.

The flat surface portion <NUM> is provided in a radially intermediate portion of the pocket <NUM> including a position through which a pitch circle diameter PCD of each cylindrical roller <NUM> passes. The outer diameter-side retaining portion <NUM> and the inner diameter-side retaining portion <NUM> are connected to the flat surface portion <NUM> by inclined surfaces <NUM>, <NUM>, respectively. Further, an angle θ1 formed by the outer diameter-side inclined surface <NUM> and the flat surface portion <NUM> is set to be smaller than an angle θ2 formed by the inner diameter-side inclined surface <NUM> and the flat surface portion <NUM> (θ1 < θ2), and is preferably set to be about <NUM>/<NUM> to <NUM>/<NUM> of the angle θ2 (θ2/<NUM> ≤ θ1 ≤ θ2/<NUM>).

Further, in the retainer <NUM> of the present embodiment, the annular portion <NUM> on the other side in the axial direction is provided with, at equal intervals in the circumferential direction, a plurality of (three in the present embodiment) protrusion portions <NUM> each having an engaging portion <NUM> protruding radially outward with respect to an inner circumferential surface of the inward flange portion <NUM>. In this case, the protrusion portion <NUM> is provided to extend toward the other side in the axial direction from an end surface on the other side in the axial direction of the annular portion <NUM>. In the engaging portion <NUM>, a portion having a triangular cross section which increase in thickness from the other side in the axial direction toward the one side in the axial direction has a predetermined circumferential length on an outer diameter side of the protrusion portion <NUM>. An outer circumferential surface of the annular portion <NUM> faces the inner circumferential surface of the inward flange portion <NUM> with a slight radial gap therebetween, and the end surface on the other side in the axial direction of the annular portion <NUM> is located on (protrudes toward) the other side in the axial direction with respect to a side surface on the other side in the axial direction of the inward flange portion <NUM>.

Accordingly, when the outer ring <NUM> is inserted into the retainer <NUM>, in which the cylindrical rollers <NUM> are assembled, from the other side in the axial direction, the engaging portions <NUM> are pressed by the inner circumferential surface of the inward flange portion <NUM> and elastically deformed toward the inner diameter side, and thus the inward flange portion <NUM> climbs over the engaging portions <NUM>. Then, the inward flange portion <NUM> is sandwiched at the outer circumferential surface of the annular portion <NUM> between axial end surfaces of the cylindrical rollers <NUM> and side surfaces on the one side in the axial direction of the protrusion portions <NUM>, and the retainer <NUM> does not fall off from the outer ring <NUM> even in the single bearing. In the related art, the cylindrical rollers are inserted from the inner side after the retainer is inserted into the outer ring, but in the present embodiment, the retainer <NUM> and the cylindrical rollers <NUM> can be combined in advance to form an intermediate assembly and then assembled to the outer ring <NUM>, and the assemblability can be improved.

Further, the outward flange portion <NUM> of the outer ring <NUM> is provided with a projection portion <NUM>, which further extends toward the outer diameter side, in a part thereof in the circumferential direction. As illustrated in <FIG>, the cylindrical roller bearing <NUM> with an outer ring is used by press-fitting the outer circumferential surface of the cylindrical portion <NUM> of the outer ring <NUM> into a mating member <NUM>, and the projection portion <NUM> is fitted into a recess portion <NUM> of the mating member <NUM>, and thus a position of the cylindrical roller bearing <NUM> with an outer ring in the circumferential direction with respect to the mating member <NUM> can be regulated, and creep can be prevented. In the present embodiment, the projection portion <NUM> is provided at one position in the circumferential direction, but may be provided at two or more positions.

Further, as illustrated in <FIG>, when an axial distance between a flat surface on the one side in the axial direction of the outward flange portion <NUM> and an end surface on the one side in the axial direction of the annular portion <NUM> on the one side in the axial direction is set as A, and an axial distance between a flat surface on the other side in the axial direction of the inward flange portion <NUM> and a side surface on the one side in the axial direction of the engaging portion <NUM> is set as B, B is greater than A (B > A), and (A + <NUM>) ≤ B ≤ (A + <NUM>) is preferably satisfied. This condition is based on the premise that an axial center of the cylindrical roller <NUM> and an axial center of the pocket <NUM> coincide with each other.

Accordingly, when another mating member <NUM> to be abutted against the flat surface on the one side in the axial direction of the outward flange portion <NUM> of the outer ring <NUM> is provided on a lateral side of the cylindrical roller bearing <NUM> with an outer ring, the retainer <NUM> is moved to a left side in the drawing, and the annular portion <NUM> is abutted against the mating member <NUM> before the engaging portions <NUM> are abutted against the inward flange portion <NUM>. Therefore, the engaging portions <NUM> of the retainer <NUM> having a relatively low strength can be prevented from being damaged due to contact with or sliding with respect to the outer ring <NUM>.

As described above, according to the cylindrical roller bearing <NUM> with an outer ring of the present embodiment, since the annular portion <NUM> on the other side in the axial direction of the retainer <NUM> is provided with the plurality of protrusion portions <NUM> each having the engaging portion <NUM> protruding radially outward with respect to the inner circumferential surface of the inward flange portion <NUM>, the inward flange portion <NUM> of the outer ring <NUM> is sandwiched between the cylindrical rollers <NUM> and the protrusion portions <NUM>, and the retainer <NUM> can be prevented from falling off from the outer ring <NUM> without increasing the number of components with good assembly workability.

Further, when the axial distance between the flat surface on the one side in the axial direction of the outward flange portion <NUM> and the end surface on the one side in the axial direction of the annular portion <NUM> on the one side in the axial direction is set as A, and the axial distance between the flat surface on the other side in the axial direction of the inward flange portion <NUM> and the side surface on the one side in the axial direction of the engaging portion <NUM> is set as B, it is set that B is greater than A, so that the engaging portions <NUM> of the retainer <NUM> are less likely to come into contact with or slide with respect to the inward flange portion <NUM> of the outer ring <NUM>, and the engaging portions <NUM> can be prevented from being damaged.

Further, on the side surface of the column portion <NUM> of the retainer <NUM>, the distance L between the flat surface portions <NUM> of the adjacent column portions <NUM> is <NUM>% to <NUM>% of the roller diameter D, the circumferential protrusion amount S1 of the outer diameter-side retaining portion <NUM> from the flat surface portion <NUM> is <NUM>% to <NUM>% of the roller diameter D, and the circumferential protrusion amount S2 of the inner diameter-side retaining portion <NUM> from the flat surface portion <NUM> is <NUM>% to <NUM>% of the roller diameter D, so that the insertion workability of the cylindrical rollers <NUM> and the prevention of the cylindrical rollers <NUM> from falling off from the retainer <NUM> can be realized.

Further, it is preferable that three or more protrusion portions <NUM> are provided at equal intervals in the circumferential direction, and thus, as illustrated in <FIG>, even when the outer ring <NUM> is an elliptical shape (in <FIG>, a vertical axis passing through the projection portion <NUM> is a short axis, and a horizontal axis is a long axis), the retainer <NUM> can be prevented from coming out of the outer ring <NUM>.

As in a first modification illustrated in <FIG>, the protrusion portions <NUM> may be provided at two positions facing each other in the radial direction. In this case, even when the outer ring <NUM> is an elliptical shape, the outer ring <NUM> can be easily assembled into the retainer <NUM> from the axial direction by matching a phase of the long axis of the outer ring <NUM> having an elliptical shape with a phase in which the protrusion portion <NUM> of the retainer <NUM> is provided.

Further, as illustrated in <FIG>, by setting a total circumferential length occupied by the protrusion portions <NUM> to <NUM>% to <NUM>% of an entire circumferential length of the axial end surface of the retainer <NUM>, the retainer <NUM> can be easily assembled into the outer ring <NUM>. When the total circumferential length of the protrusion portions <NUM> is less than <NUM>% of the entire circumferential length, the holding force is reduced, and when the total circumferential length exceeds <NUM>% of the entire circumferential length, the protrusion portions <NUM> increase in rigidity, which makes the assembly difficult.

<FIG> illustrates a second modification in which the total circumferential length of the protrusion portions <NUM> is <NUM>% of the entire circumferential length of the axial end surface of the retainer <NUM>. <FIG> illustrates a third modification in which the total circumferential length of the protrusion portions <NUM> is <NUM>% of the entire circumferential length of the axial end surface of the retainer <NUM>.

The circumferential length described above is a length along the circumferential direction at a radial position of the outer circumferential surface of the annular portion <NUM>.

Further, the shape of the engaging portion <NUM> may be a convex curved shape in cross section, that is, a substantially hemispherical shape as in a fourth modification illustrated in <FIG>. In the case of a substantially hemispherical shape, since the retainer <NUM> can be formed by axial drawing instead of radial drawing, cost reduction can be achieved.

Further, as in a fifth modification illustrated in <FIG>, the shapes of the engaging portions <NUM> formed on the plurality of protrusion portions <NUM> on the circumference may not be the same. Further, the circumferential lengths of the protrusion portions <NUM> may not be the same.

Next, a cylindrical roller bearing with an outer ring according to a second embodiment will be described with reference to <FIG>.

In a resin retainer 30a of the present embodiment, the protrusion portion <NUM> provided on a side surface of the annular portion <NUM> is located in a region in which the column portion <NUM> having high rigidity is disposed (in the same phase as the column portion <NUM>) in the circumferential direction.

Specifically, the protrusion portion <NUM> is formed at a phase (position) which is a center in the circumferential direction of the column portion <NUM>, and a circumferential length of the protrusion portion <NUM> is smaller than a circumferential length of the column portion <NUM>. When the circumferential length of the column portion <NUM> is small, the circumferential length of the protrusion portion <NUM> may be equal to or greater than the circumferential length of the column portion <NUM> in a state where a circumferential center position of the column portion and a circumferential center position of the protrusion portion <NUM> coincide with each other.

Accordingly, when an intermediate assembly in which the retainer 30a and the cylindrical rollers <NUM> are assembled in advance is assembled to the outer ring <NUM> (when the inward flange portion <NUM> of the outer ring <NUM> rides over the protrusion portions <NUM> of the retainer 30a while the protrusion portions <NUM> of the retainer 30a are elastically deformed), deformation of the retainer 30a can be restricted, and the cylindrical rollers <NUM> can be prevented from falling off from the retainer 30a.

In the first embodiment, since the protrusion portions <NUM> are disposed at equal intervals in the circumferential direction, a circumferential position relationship (phase) between the protrusion portions <NUM> and the column portions <NUM> is any relationship depending on the number of rollers. On the other hand, in the present embodiment, in order to satisfy the circumferential position relationship between the protrusion portions <NUM> and the column portions <NUM>, the protrusion portions <NUM> are not necessarily disposed at equal intervals in the circumferential direction, but are preferably disposed at positions as close to each other as possible.

Other configurations and operations are the same as those of the cylindrical roller bearing <NUM> with an outer ring of the first embodiment.

Next, a cylindrical roller bearing with an outer ring according to a third embodiment will be described with reference to <FIG>. In a resin retainer 30b of the present embodiment, the protrusion portion <NUM> provided on a side surface of the annular portion <NUM> is located in a region in which the pocket <NUM> are disposed (in the same phase as the pocket <NUM>) in the circumferential direction, and slits <NUM> extending in the axial direction from the annular portion <NUM> are formed in the column portions <NUM> on both sides in the circumferential direction of the pocket <NUM> at which the protrusion portion <NUM> is located. The slit <NUM> is formed in a circumferential center portion of the column portion <NUM> up to an axial middle position.

Accordingly, when the outer ring <NUM> is inserted from the axial direction into the retainer 30b in which the cylindrical rollers <NUM> are assembled, the protrusion portions <NUM> of the retainer 30b are easily deformed, and the assemblability between the outer ring <NUM> and the retainer 30b can be improved.

Next, a cylindrical roller bearing with an outer ring according to a fourth embodiment will be described with reference to <FIG>.

In the cylindrical roller bearing <NUM> with an outer ring according to the present embodiment, a retainer 30c includes the pair of annular portions <NUM>, <NUM>, the column portions <NUM>, and the protrusion portions <NUM> as in the above-described embodiment, but the retainer 30c is made of iron.

In the iron retainer 30c, after an intermediate assembly of the cylindrical rollers <NUM> and the retainer 30c is inserted into the outer ring <NUM>, a portion extending in the axial direction from an end portion on the other side in the axial direction of the annular portion <NUM> on the other side in the axial direction of the retainer 30c is bent outward in the radial direction to form the protrusion portions <NUM> having the engaging portions <NUM>.

Similarly to the first embodiment, the protrusion portions <NUM> are provided at three positions at equal intervals in the circumferential direction.

The present invention is not limited to the embodiments described above, and modifications, improvements, and the like can be made as appropriate as disclosed in the appended claims.

For example, in the first embodiment, an outer diameter of the annular portion <NUM> corresponds to an inner diameter of the inward flange portion <NUM> and is smaller than an outer diameter of the annular portion <NUM>. However, the outer diameter of the annular portion <NUM> may be set to be the same as the outer diameter of the annular portion <NUM> by reducing a radial dimension of the inward flange portion <NUM>. Further, the outer diameters of the pair of annular portions <NUM>, <NUM> may have the same dimension by reducing the outer diameter of the annular portion <NUM>.

Further, the protrusion portion may be formed by providing, on both sides in the circumferential direction of the protrusion portion, a slit extending toward the one side in the axial direction from an end surface on the other side in the axial direction of the annular portion on the other side in the axial direction. In this case, the protrusion portion is formed in the annular portion on the other side in the axial direction without protruding from the end surface on the other side in the axial direction of the annular portion.

Claim 1:
A cylindrical roller bearing (<NUM>) with an outer ring (<NUM>), comprising:
an outer ring (<NUM>) which includes:
a cylindrical portion having an outer ring raceway surface (<NUM>) on an inner circumferential surface thereof;
an outward flange portion (<NUM>) extending radially outward from an end portion on one side in an axial direction of the cylindrical portion; and
an inward flange portion (<NUM>) extending radially inward from an end portion on the other side in the axial direction of the cylindrical portion;
a plurality of cylindrical rollers (<NUM>) which are disposed rollably on the outer ring raceway surface (<NUM>); and
a retainer (<NUM>) which includes a pair of annular portions (<NUM>, <NUM>) spaced apart in the axial direction, and a plurality of column portions (<NUM>) connecting the pair of annular portions (<NUM>, <NUM>) and arranged at intervals in a circumferential direction, and in which the plurality of cylindrical rollers (<NUM>) are rollably held by a plurality of pockets (<NUM>) each being formed by the column portions (<NUM>) adjacent to each other and the pair of annular portions (<NUM>, <NUM>), wherein:
the annular portion (<NUM>) on the other side in the axial direction is provided with a plurality of protrusion portions (<NUM>) each having an engaging portion (<NUM>) protruding radially outward with respect to an inner circumferential surface of the inward flange portion (<NUM>), characterized in that
when an axial distance between a flat surface on the one side in the axial direction of the outward flange portion (<NUM>) of the outer ring (<NUM>) and an end surface on the one side in the axial direction of the annular portion (<NUM>) of the retainer (<NUM>) on the one side in the axial direction is set as A, and an axial distance between a flat surface on the other side in the axial direction of the inward flange portion (<NUM>) of the outer ring (<NUM>) and a side surface on the one side in the axial direction of the engaging portion (<NUM>) of the retainer (<NUM>) is set as B, B is greater than A.