JP2501793Y2 - Thrust ball bearing for suspension and its race - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The thrust ball bearing for a suspension and its race according to the present invention are provided in a suspension part of an automobile or the like while supporting a load in a thrust direction applied to a rotating part. It is used when allowing rotation of the rotating part.

(Prior Art) In a suspension of an automobile, a thrust ball bearing is provided at a rotating portion to which a thrust load is applied, so that the rotating portion is allowed to rotate while supporting the load in the thrust direction applied to the rotating portion. ing.

As is well known, a thrust ball bearing is a pair of races each formed in the shape of a circular ring and having raceways formed on the surfaces facing each other, and a plurality of balls rotatably provided between the raceways of both races. With the rolling of the plurality of balls, relative rotation between the member supporting one race and the member supporting the other race is allowed. In addition, in order to facilitate the work of mounting such a thrust ball bearing on the rotating portion, it is possible to mount a synthetic resin case on the pair of races so as to surround a portion other than the raceway surface of each race. Has been done.

FIG. 6 shows such a conventionally known thrust ball bearing with a synthetic resin case. In the thrust ball bearing with the synthetic resin case shown in FIG.
Of the synthetic resin cases 2 and 3 mounted on the pair of races 1 and 1, planted on the hook pieces 4 hanging from the lower end portions of one synthetic resin case 2 and the upper surfaces of both end portions of the other synthetic resin case 3. By engaging the hook piece 5 or the race 1 provided with each other, the synthetic resin cases 2 and 3 are prevented from being separated from each other unless a strong force is applied, thereby facilitating the handling of the thrust ball bearing. ing.

Race 1, 1 made of steel plate and hardened by quenching
Respectively have raceway surfaces 6, 6 on one side, and are fitted and held in the respective cases 2, 3 in a state where the raceway surfaces 6, 6 face each other. A plurality of balls 7 are sandwiched between the raceways 6, 6 of both races 1, 1.

Since the thrust ball bearing with a synthetic resin case is configured as described above, a member in which one case 2 is mounted based on rolling of a plurality of balls 7 sandwiched between a pair of races 1 and 1. And relative rotation of the other member mounted with the case 3 is allowed.

(Problems to be solved by the invention) However, in the case of the conventional thrust ball bearing configured and acting as described above, satisfactory performance cannot always be obtained in terms of reducing rotational torque and preventing occurrence of torque unevenness. It was

That is, in the case of a conventional thrust ball bearing for suspension, a so-called all-ball type is used, in which a cage for holding a plurality of balls 7 sandwiched between a pair of races 1, 1 is not provided. Rolling surfaces of adjacent balls 7 are in sliding contact with each other,
The force required for rolling each ball 7 increases, the rotational torque of the thrust ball bearing increases, and the rotational torque becomes unstable. Further, the rotational torque becomes large and unstable even when the races 1 and 1 have poor shape accuracy.

In particular, when the pair of races are manufactured by press working in order to reduce the manufacturing cost of the thrust ball bearing for suspension, the rotational torque becomes more unstable. That is, instead of the races 1, 1 made by cutting as shown in FIG. 6, the first, third embodiments of the present invention are shown.
As shown in the figure, if the races 8 and 8 are formed by press working, the manufacturing cost of the thrust ball bearing for suspension including the races 8 and 8 can be reduced. However, the races 8 and 8 produced by the press work need to be heat-treated after the press work, and distortion is likely to occur during this heat treatment. If they occur, the races 8 and 8 are spread in the circumferential direction. The shape becomes wavy. When the races 8 and 8 have a wavy shape, the races 8 and 8 interfere with the cage, and the rotational torque becomes unstable.

The thrust ball bearing for suspension and the race thereof according to the present invention eliminate all of the above inconveniences.

(Means for Solving the Problems) Of the thrust ball bearings for suspension and the races thereof according to the present invention, the thrust ball bearing for suspension described in claim 1 is the same as the above-mentioned conventional thrust ball bearing for suspension. A pair of races formed in a ring shape and having raceway surfaces formed on the surfaces facing each other, an annular synthetic resin case for holding each race with the raceway surface exposed, and raceways for both races It is composed of a plurality of balls provided between the surfaces.

Particularly, in the thrust ball bearing for suspension of the present invention, the pair of races are formed by pressing metal plates, and the plurality of balls are each formed in an arc shape. It is made of synthetic resin and can be rolled and made of synthetic resin by using a split type synthetic resin cage that is used as it is in a separated state by dividing the ring in the circumferential direction It is held inseparably from the cage.

Further, the race of the thrust ball bearing for suspension according to claim 2 is made of a metal ring-shaped main body, a raceway surface formed on the entire circumference of one side of the main body, and having a concave cross section, and the raceway. One side flat part existing on the inner peripheral side and outer peripheral side of the surface, a convex part formed on the entire other surface of the main body, and the other surface side existing on the inner peripheral side and outer peripheral side of the convex part And a flat portion. The height dimension of the convex portion is smaller than the depth dimension of the raceway surface, and the width dimension of the convex portion is smaller than the width dimension of the raceway surface.

(Operation) When the thrust ball bearing for suspension of the present invention as described above supports the load in the thrust direction applied to the rotating portion while allowing the rotation of the rotating portion, the operation itself is the same as that for the conventional suspension described above. Similar to thrust ball bearings.

Particularly, in the case of the thrust ball bearing for suspension of the present invention, since the plurality of balls provided between the pair of races are held by the synthetic resin cage, the rolling surfaces of the adjacent balls are mutually Since there is no sliding contact, the torque required to rotate the thrust ball bearing is small and stable.

Also, because the cage made of synthetic resin is of the split type that is split along the circumferential direction and used in the separated state, the cage shape accuracy including roundness and flatness is sufficient. It is possible to make the rolling of the plurality of balls secured by the retainer smoother.

Further, since the pair of races are made by pressing the metal plates, the manufacturing cost of the thrust ball bearing for suspension can be reduced. Moreover, even if the race has a wavy shape due to the distortion generated during the heat treatment, it is possible to prevent the rotational torque from becoming unstable due to the interference between the race and the cage. That is, when the race is deformed into a corrugated shape, the restraining force between some balls and the retainer holding these balls changes (becomes larger), and the resistance of the balls to the rotation motion, and further The resistance against orbital movement of the balls and the cage is increased. This increase in resistance causes an increase in resistance to the rotation movement and the revolution movement of the other balls held by the cage. Therefore, in the case of the thrust ball bearing in which the annular and integral type retainer is incorporated, the resistances of all the balls to the rotational movement and the revolution movement change at the same time, and the fluctuation of the rotational torque becomes large. On the other hand, in the case of a split type cage that is used by being divided in the circumferential direction and used in a separated state, the resistance to the orbital movement of some balls and the cage holding the balls is Even if it increases, the increase in resistance is limited to only some of the cages formed in an arc shape and the balls held by the cages. Therefore,
Even if the race has a wavy shape, it is not so unstable that the rotational torque becomes a problem.

Further, in the case of the race of the thrust ball bearing for suspension according to the second aspect, the convex portion on the other surface of the race can also completely enter inside the raceway surface on one side of the race. As a result, in a state where a plurality of materials, each of which is a race, are overlapped, the one-side flat portion and the other-side flat portion that are adjacent to each other in the overlapping direction come into close contact with each other. In this way, the one-side flat portion and the other-side flat portion are brought into close contact with each other,
If a plurality of materials are superposed on each other and these materials are held down by a jig, it is possible to prevent the materials from being distorted during the quenching process. Therefore, it is possible to obtain the race of the thrust ball bearing for suspension which is excellent in shape accuracy and dimensional accuracy. Therefore, the torque of the thrust ball bearing for suspension incorporating this race is smaller and stable.

(Embodiment) FIGS. 1 to 5 show an embodiment of a thrust ball bearing for suspension of the present invention. A pair of races 8 and 8 formed by further press-molding a metal plate punched and formed into a ring shape in advance form raceway surfaces 9 and 9 on the surfaces facing each other. Such a pair of races 8 and 8 are held in annular synthetic resin cases 10 and 10 with the raceway surfaces 9 and 9 exposed. Each synthetic resin case
The inner surface of 10, 10 is formed with a concave portion 11, 11 so that each race 8, 8
One side of the projecting part that protrudes on the opposite side of the raceway surfaces 9 and 9
12 and 12 can be stored freely. With this structure, the races 8 and 8 are fitted inside the synthetic resin cases 10 and 10 without rattling. The above pair of synthetic resin case 1
Hook pieces 4 and 5 which engage with each other are formed on 0 and 10 so that both synthetic resin cases 10 and 10 are not separated carelessly. Also, a pair of races 8 configured as described above,
A plurality of balls 7, 7 are provided between the orbital surfaces 9, 8.

Further, the plurality of balls 7, 7 are rollable and non-separated by a split type synthetic resin cage 13 as shown in FIG.
That is, the balls 7, 7 are held so as not to be separated from the synthetic resin cage 13 unless a strong force is applied. The above-mentioned split type synthetic resin cage 13 is like an annular ring divided in the circumferential direction, and each is formed in an arc shape, and becomes an annular shape in a combined state. This synthetic resin cage 13 has pockets for holding the balls 7 one by one inside the cage and holding them inseparably with respect to the synthetic resin cage.
A plurality of 14, 14 are provided. More specifically, a pair of tongue pieces 2 are respectively provided in the openings at both ends of each of the pockets 14, 14.
5 and 25 are formed, and these tongue pieces 25 and 25 prevent the balls 7 and 7 from falling out of the pockets 14 and 14, respectively.

The suspension ball bearing for suspension of the present invention as described above, while supporting the load in the thrust direction applied to the rotating portion, allows the rotation of the rotating portion. The action itself is the above-mentioned conventional thrust ball bearing for suspension. Is the same as.

Particularly, in the case of the thrust ball bearing for suspension of the present invention, a plurality of balls 7 provided between a pair of races 8,
7 is held by a synthetic resin cage 13. Therefore, the rolling surfaces of the adjacent balls 7, 7 do not come into sliding contact with each other, and the torque required for the rotation of the thrust ball bearing becomes small and stable.

Further, since the synthetic resin cage 13 is a split type that is divided in the circumferential direction and is used in a separated state, even when the synthetic resin cage 13 is formed thin. , The shape accuracy of the synthetic resin cage 13 including the roundness and the flatness is sufficiently secured, and the rolling of the plurality of balls 7, 7 held by the synthetic resin cage 13 is made smoother. I can.

Further, a pair of races 8, 8 that rotate with each other while sandwiching the plurality of balls 7, 7 are made by pressing a metal plate. In this way, race 8 by press molding,
When manufacturing No. 8, first, a ring-shaped main body 15 made of a steel plate that has not been quenched is press-molded. And the body 15
The track surface 9 whose cross section is recessed in an arc shape is formed on the entire circumference of one surface (the upper surface in FIG. 4) of the above, and at the same time, the convex portion 12 is formed on the entire other surface of the main body 15 (the lower surface in FIG. Race material 16

In particular, when the raceway surface 9 and the convex portion 12 are press-molded, the thickness dimension of a part of the main body 15 sandwiched between the raceway surface 9 and the convex portion 12 is compressed. By compressing the thickness dimension in this way, the height dimension H of the convex portion 12 is made smaller than the depth dimension D of the raceway surface 9 (H <D), and the width dimension of the convex portion 12 is made. w is made smaller than the width dimension W of the raceway surface 9 (w <W). As a result of regulating the sizes of the raceway surface 9 and the convex portion 12 in this way, the convex portion 12 on the other surface of the race material 16 can completely enter the inside of the raceway surface 9 on one side of the race material 16 as well. .

After forming the race material 16 having the raceway surface 9 and the convex portion 12 having the above-mentioned dimensions, a plurality of race materials 16, 16 are superposed as shown in FIG. In the case of overlapping in this manner, the convex portion 12 on the other surface of each race material 16 can completely enter the inside of the raceway surface 9 on one side of each race material 16 as described above. For this reason, as shown in FIG. 4, when a plurality of lace materials 16, 16 are piled up, each lace material is
The one-side flat portions 17, 17 existing on the inner and outer peripheral sides of the raceway surfaces 9, 9 of 16, 16 and the inner peripheral side and the outer peripheral side of the convex portion 12 of each race material 16, 16. The other-side flat portions 18, 18 are in close contact with each other.

In this way, the flat parts 17, 17 on one side and the flat parts 18, 18 on the other side are
Multiple lace materials 16, 16 in close contact with each other
These multiple lace materials if stacked on top of each other
The jigs 16 as shown in FIG. 5 are used to hold the 16 and 16 together to prevent the lace materials 16 and 16 from being distorted during the subsequent quenching process.

The jig 19 includes a pair of upper and lower restraining plates 20 and 21, and both restraining plates.
It is composed of bolts 22 and 22 and nuts 23 and 23 that connect 20 and 21 together. One (lower side in Fig. 5) restraining plate 21
The surface of one of the surfaces facing the other restraining plate 20 (the upper surface in FIG. 5)
In this, concave portions 24, 24 for allowing the convex portion 12 formed on the other surface of the lace material 16 to enter are formed. As a result, the other surface side flat portions 18, 18 of the lace material 16 existing at the end and one surface of the one restraining plate 21 can be brought into close contact with each other.

When a plurality of lace materials 16, 16 that are overlapped with each other are sandwiched by the pair of presser plates 20, 21 that form the jig 19 as described above, the bolts 22, 22 and the nuts 23, 23 are tightened. As a matter of fact, the pair of restraining plates 20 and 21 strongly restrain the plurality of lace materials 16 and 16. Then, in a state in which the plurality of lace materials 16, 16 are strongly suppressed in this way, the plurality of lace materials 16, 16 are put into a heating furnace together with the jig 19 and quenched to form races 8, 8. .

The action itself of the races 8 and 8 produced by the above-described process is the same as that of the conventionally known race produced by shaving, but when the race is produced by press working,
The manufacturing process of the race can be simplified and the production cost of the race can be reduced. Further, since the pair of races 8 and 8 are formed by pressing the metal plates respectively, the manufacturing cost of the thrust ball bearing for suspension can be reduced. Moreover, even if the races 8 and 8 have a wavy shape due to the strain generated during the heat treatment,
It is possible to prevent the rotational torque from becoming unstable due to the interference between the rotor 8 and the cage 13. That is, when the races 8 and 8 are deformed into a corrugated shape, the binding force between a part of the balls 7 and the synthetic resin cage 13 holding the part of the balls 7 changes (becomes larger), and The resistance against the rotation movement of the ball 7, and further the resistance against the revolution movement of the ball 7 and the cage 13 becomes large. This increase in resistance causes an increase in resistance to the rotation movement and the revolution movement of the other balls 7, 7 held by the cage 13. Therefore, in the case of a thrust ball bearing that incorporates an annular and integral type retainer as in the conventional structure, the resistances of all the balls to the rotational movement and the revolution movement change at the same time, and the fluctuation of the rotational torque is large. Become. On the contrary,
As in the present invention, in the case of a thrust ball bearing incorporating a split type synthetic resin cage 13 which is divided in the circumferential direction and used in a separated state, some of the balls 7 and Ball 7
Even if the resistance to the orbital motion of the synthetic resin cage 13 that holds is increased, the increase in resistance is retained by a part of the synthetic resin cage 13 formed in an arc shape and the synthetic resin cage 13. It stops only at the balls 7, 7. Therefore, even if the races 8 have a corrugated shape, the rotational torque does not become unstable enough to cause a problem.

Particularly, in the case of the thrust ball bearing race for suspension of the present invention, the dimensional accuracy and the shape accuracy are stable, so that the thrust ball bearing for suspension incorporating the races 8 and 8 can rotate more smoothly (rotation). The torque is low and stable).

(Effects of the Invention) The thrust ball bearing for suspension of the present invention is constructed and operates as described above, so that the torque required for rotation can be made small and stable, and a suspension ball bearing incorporating this thrust ball bearing can be made. Performance can be improved.
In addition, the manufacturing cost can be reduced while preventing the rotational torque from becoming unstable.

Furthermore, the race of the thrust ball bearing for suspension can obtain a race of the ball bearing for suspension with high accuracy, and the performance of the ball bearing for suspension incorporating this race can be improved.

[Brief description of drawings]

1 to 5 show an embodiment of a thrust ball bearing for suspension according to the present invention. FIG. 1 is a vertical sectional view showing the entire structure, and FIG. 2 is one of split type cages holding balls. Fig. 3 is a plan view showing an individual piece, Fig. 3 is an enlarged sectional view of part A in Fig. 1, and Fig. 4 is a sectional view showing a state in which race materials for making a race to be incorporated in a thrust ball bearing for suspension are overlapped,
FIG. 5 is a vertical sectional front view showing a state in which a plurality of superposed race materials are held down by a jig, and FIG. 6 is a half sectional view of a conventional thrust ball bearing for suspension. 1: Race, 2, 3: Synthetic resin case, 4, 5: Hook piece, 6: Raceway surface, 7: Ball, 8: Race, 9: Raceway surface, 10: Synthetic resin case, 11: Recess, 12 : Convex part, 13: Synthetic resin cage, 14: Pocket, 15: Main body, 16: Lace material, 17: One side flat part, 18:
Other side flat part, 19: jig, 20, 21: restraining plate, 22: bolt, 2
3: Nut, 24: Recess, 25: Tongue.

Claims (2)

(57) [Scope of utility model registration request] 1. A pair of races each having a circular ring shape and raceway surfaces formed on the surfaces facing each other, and each race.
In a thrust ball bearing for suspension comprising an annular synthetic resin case for holding the raceway surface in an exposed state and a plurality of balls provided between the raceway surfaces of both races, The race is made by pressing each metal plate, and the plurality of balls are formed into an annular shape by combining them in an arc shape. A thrust ball for suspension characterized in that it is held by a split type synthetic resin cage that is split and used in a separated state, and is held in a non-separable manner with respect to the synthetic resin cage. bearing. 2. A metal ring-shaped main body, a raceway surface formed on the entire circumference of one side of the main body and having a concave arcuate section, and present on the inner and outer circumference sides of the raceway surface. A single-sided flat portion, a convex portion formed on the entire other surface of the main body, and the other-side flat portion existing on the inner peripheral side and the outer peripheral side of the convex portion,
A race for a thrust ball bearing for suspension, wherein a height dimension of the convex portion is smaller than a depth dimension of the raceway surface, and a width dimension of the convex portion is smaller than a width dimension of the raceway surface.