JP2022185519A - Assembly method of conical bearing - Google Patents

Abstract

To provide an assembly method of a conical bearing which can inhibit deformations, such as oval deformation and twisting deformation, which affect rotation performance of the conical bearing and eliminate a need of pursuing strict dimensional tolerance to enable reduction of assembly costs.SOLUTION: A retainer 14 and an inner ring 12 are arranged relative to each other so that a radial axis of the retainer matches with a radial axis of the inner ring and multiple conical rollers 13 contact with a small flange part 15 of the inner ring in a state that the multiple conical rollers are retained by the retainer. At least one of the retainer and the inner ring is pressed along an axial direction parallel to the axis to move the retainer to the side of a large flange part 16 of the inner ring relative to the inner ring and cause the retainer to be deformed to the radial outer side through elastic deformation and plastic deformation. When the conical roller has passed through the small flange part of the inner ring, the retainer deformed to the radial outer side is deformed to the radial inner side to a position, at which the roller is prevented from getting over the small flange part and being removed, by spring back.SELECTED DRAWING: Figure 2

Description

The present invention relates to a tapered roller bearing assembly method.

2. Description of the Related Art Conventionally, tapered roller bearings have been used as bearings for rotatably supporting rotary mechanisms in various driving devices including construction machinery. As shown in FIG. 4, this tapered roller bearing 10 includes an outer ring 11 having an outer ring raceway surface 11a on its inner peripheral surface, an inner ring 12 having an inner ring raceway surface 12a on its outer peripheral surface, an outer ring raceway surface 11a and an inner ring raceway surface 12a. and a plurality of tapered rollers 13 that are rotatably provided between them, and a retainer 14 that holds the plurality of tapered rollers 13 at predetermined intervals in the circumferential direction.

As the cage 14 of the tapered roller bearing 10, one made of resin or metal is used. A method of assembling the tapered roller bearing 10 using the metal retainer 14 adopts a so-called caulking method. Specifically, as shown in FIG. 5 , first, tapered rollers 13 are held in pockets of retainer 14 and incorporated into inner ring 12 . Then, the crimping jig 20 in contact with the retainer 14 is pushed toward the retainer 14 while the axial end face of the inner ring 12 on the side of the large flange portion 16 is in contact with the inner ring support surface 30 . , so that the inner ring 12, the tapered rollers 13 and the cage 14 are not separated from each other. It is a method of crimping until it becomes a gap that does not move and come off the inner ring 12).

For example, in the tapered roller bearing of Patent Document 1, prior to incorporating the tapered rollers and the cage into the inner ring, a tapered diameter expansion punch is fitted into the bottom hole to expand the diameter of the small diameter ring portion, and then the diameter of the small diameter ring is expanded. It is known to improve the dimensional and shape accuracy of the retainer by crimping only the vicinity of the connecting portion with the column portion inwardly with a crimping jig.

JP-A-2000-266063

By the way, since the crimping method applies a large load to the bearing, there is a possibility that the retainer loses its shape. Moreover, crimping requires a large cost, and especially in the assembly of a large-sized bearing, a large-sized press device is required, which causes a serious cost problem. Furthermore, since the caulking die requires a special design for each cage, in the case of small-lot products, the production cost for the dedicated die must be borne by a small number of cages, resulting in lower product costs. It becomes a factor to increase.

In view of the problems described above, there is a non-crimping method for assembling a tapered roller bearing that does not use crimping. In this method, an engagement margin is secured in advance between the small flange portion of the inner ring and the tapered rollers to prevent the cage from coming off. At the time of assembly, the retainer is arranged outside the inner ring by causing the retainer to spring back, and furthermore, the retainer is attached to the inner ring by the engagement allowance.

Specifically, as shown in FIG. 6, while the inner ring 12 is tilted with respect to the retainer 14 holding the tapered rollers 13 in advance, the inner ring 12 is pushed down for assembly. In this example, the axis B of the inner ring 12 is inclined at a predetermined angle with respect to the axis C of the retainer 14 perpendicular to the floor surface, such as the inner ring support surface 30. Push down to force the inner ring 12 into the retainer 14 . When the small flange portion 15 of the inner ring 12 contacts the rolling surface of the tapered roller 13 , the tapered roller 13 moves outward, and the retainer 14 deforms outward along with the movement of the tapered roller 13 .

At this time, the retainer 14 is deformed within the range of elastic deformation, and then returns to its original shape when the inner ring 12 is completely pushed. As a result, the tapered rollers 13 are held by the small flange portion 15 of the inner ring 12 by the engagement margin secured in advance, and the retainer 14 is attached to the inner ring 12 .

As described above, if the cage 14 can be deformed within the range of elastic deformation and returned to its original shape, the shape of the cage 14 will not collapse. It is not easy in terms of design to incorporate a retainer that is relatively low and has an engagement margin necessary to prevent falling off after assembling without losing its shape. Of course, it is necessary to strictly define and manage the dimensional tolerances of the inner ring 12 and the retainer 14, which may lead to an increase in manufacturing cost and management cost. Moreover, even if dimensional tolerances are strictly defined and managed, it is not easy to secure the necessary engagement allowance for assembly.

The present invention has been made in view of the above-mentioned problems, and its object is to suppress deformation such as elliptical deformation and torsional deformation of the retainer, which affects the rotational performance of the tapered roller bearing, and to achieve a precise dimension. To provide a method for assembling a tapered roller bearing capable of suppressing assembly costs without pursuing tolerance.

The above objects of the present invention are achieved by the following configurations.
(1) an outer ring having an outer ring raceway surface on its inner peripheral surface;
an inner ring having an inner ring raceway surface on its outer peripheral surface;
a plurality of tapered rollers rotatably provided between the outer ring raceway surface and the inner ring raceway surface;
a metal retainer that retains the plurality of tapered rollers at predetermined intervals in the circumferential direction;
with
A method for assembling a tapered roller bearing in which a large flange portion is provided on the large diameter side end of the inner ring and a small flange portion is provided on the small diameter side end of the inner ring,
In a state in which the plurality of tapered rollers are held by the cage, the radial axis of the cage and the radial axis of the inner ring are aligned, and the plurality of tapered rollers are aligned with the inner ring. disposing the retainer and the inner ring relative to each other so as to be in contact with the small flange;
By pressing at least one of the retainer and the inner ring along an axial direction parallel to the axis, the retainer is moved relative to the inner ring toward the large flange portion of the inner ring. move towards
deforming the retainer radially outward by elastic deformation and plastic deformation as the retainer moves;
When the tapered rollers pass the small flange portion of the inner ring as the retainer moves, the retainer deformed radially outward is moved by springback to a position where the rollers do not slip over the small flange portion. deform radially inward,
How to assemble a tapered roller bearing.
(2) The tapered element according to (1), wherein the retainer is deformed radially inward by springback to ensure a necessary engagement allowance between the tapered rollers and the small flange portion of the inner ring. A roller bearing assembly method.
(3) The tapered roller according to (2), wherein the small-diameter end faces of the tapered rollers contact a small flange surface of the small flange portion of the inner ring, and the tapered roller small-diameter end faces are held by the small flange surface. A roller bearing assembly method.
(4) The initial dimensions of the cage are such that, when the plurality of tapered rollers and the cage are incorporated into the inner ring, a necessary engagement allowance is secured between the tapered rollers and the small flange portion of the inner ring. The method for assembling a tapered roller bearing according to (1), which is designed to

According to the present invention, it is possible to suppress deformation such as elliptical deformation and torsional deformation of the retainer that affects the rotational performance of the tapered roller bearing. Moreover, it is possible to suppress the retainer from falling off from the inner ring without pursuing strict dimensional tolerances, and to suppress assembly costs.

FIG. 1 is a cross-sectional view for explaining an outline of a method for assembling a tapered roller bearing according to the present invention. 2A and 2B are cross-sectional views for explaining the procedure for assembling a tapered roller bearing by a non-crimping method according to the present invention, and FIG. , (b) shows a state in which the retainer is deformed outward due to elastic deformation and plastic deformation, and (c) is a view in which the retainer is deformed inward due to springback, and the tapered rollers are held by the small flange portion by the engagement allowance. FIG. 10 is a diagram showing a state in which FIG. 3 is a schematic diagram for explaining springback. FIG. 4 is a cross-sectional view illustrating an example of a tapered roller bearing. FIG. 5 is a cross-sectional view for explaining a method of assembling a conventional tapered roller bearing, and is a diagram for explaining a force transmission path during crimping. FIG. 6 is a cross-sectional view illustrating an outline of a tapered roller bearing assembly method using a conventional non-crimping method.

Hereinafter, each embodiment of the method for assembling a tapered roller bearing according to the present invention will be described in detail based on the drawings.

First, a tapered roller bearing to which the present invention is applied will be described with reference to FIG.

As shown in FIG. 4, the tapered roller bearing 10 includes an outer ring 11 having an outer ring raceway surface 11a on its inner peripheral surface, an inner ring 12 having an inner ring raceway surface 12a on its outer peripheral surface, an outer ring raceway surface 11a and an inner ring raceway surface 12a. A plurality of tapered rollers 13 provided to be able to roll between them, and a metal retainer 14 that retains the plurality of tapered rollers 13 at predetermined intervals in the circumferential direction.

The inner ring 12 has a small flange portion 15 provided at the small diameter end portion of the inner ring 12 and a large flange portion 16 provided at the large diameter end portion of the inner ring 12 . The small flange surface 15 a of the small flange portion 15 contacts the small diameter side end surface 13 a of the tapered roller 13 . Also, the large flange surface 16 a of the large flange portion 16 contacts the large diameter side end surface 13 b of the tapered roller 13 .

The retainer 14 is formed, for example, by pressing an iron plate, and includes a small-diameter side annular portion 14a, a large-diameter side annular portion 14b coaxially arranged with the small-diameter side annular portion 14a, and a small-diameter side annular portion 14b. A plurality of pillars 14c arranged at predetermined intervals (for example, approximately equal intervals) in the circumferential direction so as to connect the pillars 14a and the large-diameter side annular portion 14b, and each pillar adjacent to each other in the circumferential direction A pocket portion 14d is formed between the portions 14c to hold the tapered rollers 13 in a rollable manner.

The present invention provides a method for assembling such a tapered roller bearing, and will continue to describe the embodiments.

An embodiment of a method for assembling a tapered roller bearing according to the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view illustrating a method of assembling the retainer 14 holding the tapered rollers 13 to the inner ring 12 in a tapered roller bearing provided with a retainer 14 made of metal.

In the assembly method of the present embodiment, a plurality of tapered rollers 13 are held in the pocket portions 14d of the retainer 14 in advance. With the tapered rollers 13 held by the cage 14, the inner ring 12 is arranged inside the cage 14 and the inner ring 12 is pushed down. At this time, unlike the example of FIG. 6, the radial axis A of the retainer 14 coincides with the radial axis A of the inner ring 12 . Further, the outer diameter surface of the small flange portion 15 of the inner ring 12 is in contact with the rolling surface 13c of each tapered roller 13 at the point of contact D. As shown in FIG.

As the inner ring 12 is pushed down, the retainer 14 is deformed (diameter expanded) so as to expand radially outward. Since the axis A of the retainer 14 and the axis A of the inner ring 12 are aligned, it is possible to suppress deformation such as oval deformation and torsional deformation of the retainer 14 .

The details of the tapered roller bearing assembly method will be described with reference to FIG. First, as shown in FIG. 2(a), the cage 14 and the inner ring 12 are arranged relative to each other so that the rolling surfaces 13c of the tapered rollers 13 come into contact with the small flange portion 15 of the inner ring 12. As shown in FIG. That is, the state of FIG. 2(a) matches the state of FIG. At this time, the small-diameter side annular portion 14a of the retainer 14 is located at the initial position P1 in the radial direction.

Next, as shown in FIG. 2(b), at least one of the retainer 14 and the inner ring 12, in this example, the inner ring 12, is pressed downward along the axial direction parallel to the axis. The cage 14 and the tapered rollers 13 move relative to the inner ring 12 toward the large flange portion 16 side of the inner ring 12 .

The rolling surfaces 13 c of the tapered rollers 13 are in contact with the outer diameter surface of the small flange portion 15 of the inner ring 12 while being inclined outward with respect to the axial center A of the cage 14 and the inner ring 12 . Therefore, the tapered rollers 13 move radially outward as they move toward the large flange portion 16 side of the inner ring 12 . As the tapered rollers 13 move, the retainer 14 that holds the tapered rollers 13 is pushed by the small flange portion 15 and moves while being deformed so as to expand radially outward.

The expansion deformation of the metallic retainer 14 is initially an elastic deformation capable of returning to its original shape. When the retainer 14 expands to a diameter greater than or equal to a predetermined value, the metal material forming the retainer 14 reaches a yield point, and the expanding deformation of the retainer 14 changes from elastic deformation to plastic deformation, and further expands radially outward. Due to the expansion deformation, the small diameter side annular portion 14a of the retainer 14 moves to the diameter expansion position P2.

The retainer 14 expands due to plastic deformation, but when the plastic deformation ends within a predetermined range, it can be deformed in the direction of returning to its original shape by springback, that is, deformed (reduced in diameter) radially inward. is. When the small-diameter side annular portion 14a of the retainer 14 has moved to the enlarged diameter position P2, the retainer 14 is capable of such springback.

Under such circumstances, the rolling surface 13c of the tapered roller 13 passes over the small flange portion 15 of the inner ring 12, as shown in FIG. 2(c). As a result, the retainer 14 with its expanded diameter is deformed (diameter-reduced) in the direction of returning to its original shape, that is, radially inward due to springback. As a result, the tapered rollers 13 are housed between the small flange portion 15 and the large flange portion 16 of the inner ring 12 . At this time, the small-diameter side annular portion 14a of the retainer 14 moves to the fixed position P3. At the fixed position P3, even if the roller 13 tries to move to the outer diameter side, the pocket clearance is set so that it cannot move beyond the small flange portion 15.

FIG. 3 is a schematic diagram for explaining springback, in which the vertical axis represents the load applied to the retainer and the horizontal axis represents deformation (amount of deformation) of the retainer. At the initial position in FIG. 2(a), the load and deformation in FIG. 3 are 0, and when the state in FIG. 2(a) changes to the state in FIG. It reaches B in FIG. 3 in the state of FIG. When the state shown in FIG. 2(b) changes to the state shown in FIG. 2(c), the state changes from B to C in FIG. Springback is the difference between B1, which is the amount of deformation of B in FIG. 3, and the amount of deformation of C. FIG.

As a result, a necessary engagement allowance is secured between the tapered rollers 13 and the small flange portion 15 of the inner ring 12 , and the tapered rollers 13 are held by the small flange portion 15 . Specifically, the small diameter end face 13a of the tapered roller 13 contacts the small flange face 15a of the small flange portion 15, and the small diameter end face 13a is held by the small flange face 15a. As a result, the retainer 14 is assembled to the inner ring 12 together with the tapered rollers 13 .

According to the assembly method of the present embodiment, since the axis A of the cage 14 and the axis A of the inner ring 12 are aligned, there is no elliptical deformation of the cage 14 that affects the rotational performance of the tapered roller bearing 10 . , torsional deformation, etc., can be suppressed.

In addition, the initial dimensions of the retainer 14 are set in advance to values that take into consideration the diameter expansion due to elastic deformation, plastic deformation, and springback, so that the influence of the diameter expansion on the performance of the tapered roller bearing 10 can be avoided. . By permitting the plastic deformation of the retainer 14 in advance, it is possible to generate an engagement allowance for the springback regardless of the dimensional tolerances of the retainer 14 and the inner ring 12 . Therefore, it is possible to prevent the retainer 14 from falling off from the inner ring 12 without pursuing strict dimensional tolerances. Moreover, since a large-scale apparatus unlike the crimping method is not required, the assembly cost can be suppressed.

In addition, by considering the shape of the retainer 14 and the physical properties of the metal material (Young's modulus, yield point, etc.), the deformation amount of the elastic deformation of the retainer 14 that turns into plastic deformation, It is possible to predict (simulate) the amount of plastic deformation. By using prediction to derive the initial dimensions of the cage 14, it is possible to eliminate as much as possible the effects of plastic deformation on the tapered roller bearing 10 as a finished product.

In the above description, the inner ring 12 is pushed down toward the retainer 14 arranged on the floor. However, the inner ring 12 may be placed on the floor and the retainer 14 may be pushed down from above. Alternatively, both the inner ring 12 and the retainer 14 may be assembled so as to be relatively close to each other.

It should be noted that the present invention is not limited to those exemplified in the above embodiments, and can be modified, improved, etc. as appropriate.

10 Tapered roller bearing 11 Outer ring 11a Outer ring raceway surface 12 Inner ring 12a Inner ring raceway surface 13 Tapered roller 13a Small diameter side end face 13b Large diameter side end face 13c Rolling surface 14 Cage 14a Small diameter side annular portion 14b Large diameter side annular portion 14c Column Part 14d Pocket portion 15 Small flange portion 15a Small flange surface 16 Large flange portion 16a Large flange surface 20 Crimping jig

Claims (4)

an outer ring having an outer ring raceway surface on its inner peripheral surface;
an inner ring having an inner ring raceway surface on its outer peripheral surface;
a plurality of tapered rollers rotatably provided between the outer ring raceway surface and the inner ring raceway surface;
a metal retainer that retains the plurality of tapered rollers at predetermined intervals in the circumferential direction;
with
A method for assembling a tapered roller bearing in which a large flange portion is provided on the large diameter side end of the inner ring and a small flange portion is provided on the small diameter side end of the inner ring,
In a state in which the plurality of tapered rollers are held by the cage, the radial axis of the cage and the radial axis of the inner ring are aligned, and the plurality of tapered rollers are aligned with the inner ring. disposing the retainer and the inner ring relative to each other so as to be in contact with the small flange;
By pressing at least one of the retainer and the inner ring along an axial direction parallel to the axis, the retainer is moved relative to the inner ring toward the large flange portion of the inner ring. move towards
deforming the retainer radially outward by elastic deformation and plastic deformation as the retainer moves;
When the tapered rollers pass the small flange portion of the inner ring as the retainer moves, the retainer deformed radially outward is moved by springback to a position where the rollers do not slip over the small flange portion. deform radially inward,
How to assemble a tapered roller bearing. 2. The tapered roller bearing according to claim 1, wherein the retainer is deformed radially inward by springback to ensure a necessary engagement allowance between the tapered rollers and the small flange portion of the inner ring. Assembly method. 3. The tapered roller bearing according to claim 2, wherein the small-diameter side end faces of the tapered rollers contact a small flange surface of the small flange portion of the inner ring, and the small-diameter side end faces of the tapered rollers are held by the small flange surface. Assembly method. The initial dimensions of the retainer are such that when the plurality of tapered rollers and the retainer are incorporated into the inner ring, a necessary engagement allowance is secured between the tapered rollers and the small flange portion of the inner ring. A method for assembling a tapered roller bearing according to claim 1, designed.

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