JP5030187B2 - Grease filling method for wheel bearing device - Google Patents

Description

  The present invention relates to a wheel bearing device for rotatably supporting a wheel of an automobile or the like, and more particularly to a grease for a wheel bearing device that increases bearing rigidity and ensures optimum lubrication conditions to extend the life of the bearing. It relates to an encapsulation method.

  2. Description of the Related Art Conventionally, a wheel bearing device for supporting a wheel of an automobile or the like is such that a hub wheel for mounting a wheel is rotatably supported via a rolling bearing, and there are a drive wheel and a driven wheel. For structural reasons, an inner ring rotation method is generally used for driving wheels, and an inner ring rotation method and an outer ring rotation method are generally used for driven wheels. As the wheel bearing device, a double-row angular ball bearing having a desired bearing rigidity, exhibiting durability against misalignment, and having a small rotational torque from the viewpoint of improving fuel efficiency is often used. In this double row angular contact ball bearing, a plurality of balls are interposed between a fixed ring and a rotating ring, and a predetermined contact angle is given to the balls so as to contact the fixed ring and the rotating ring.

  Further, the wheel bearing device has a structure called a first generation in which a wheel bearing composed of a double row angular ball bearing or the like is fitted between a knuckle and a hub wheel constituting a suspension device. Second generation structure in which body mounting flange or wheel mounting flange is formed directly on the outer periphery of the member, third generation structure in which one inner rolling surface is directly formed on the outer periphery of the hub wheel, or hub wheel, etc. It is roughly classified into a fourth generation structure in which the inner rolling surface is directly formed on the outer periphery of the outer joint member of the speed universal joint. In the following description, the side closer to the outer side of the vehicle in a state assembled to the vehicle is referred to as the outer side (left side in the drawing), and the side closer to the center is referred to as the inner side (right side in the drawing).

  In wheel bearing devices composed of such double-row rolling bearings, the left and right rows of bearings have the same specifications, so that they have sufficient rigidity when stationary, but optimal rigidity is always obtained when the vehicle turns. Absent. That is, the position of the vehicle weight when stationary is determined so that it acts on the approximate center of the double row rolling bearing, but when turning, the opposite side of the turning direction (when turning right, the vehicle Larger radial load or axial load is applied to the left axle. Therefore, at the time of turning, it is effective to increase the rigidity of the outer bearing row rather than the inner bearing row. Therefore, a wheel bearing device shown in FIG. 3 is known as a wheel bearing device that achieves high rigidity without increasing the size of the device.

  This wheel bearing device 50 has a vehicle body mounting flange 51c integrally attached to a knuckle (not shown) on the outer periphery, and an outer side in which double row outer rolling surfaces 51a and 51b are formed on the inner periphery. A member 51 and a wheel mounting flange 53 for mounting a wheel (not shown) at one end are integrally formed, and one inner rolling surface 52a facing the double row outer rolling surfaces 51a and 51b on the outer periphery. The hub wheel 52 having a small-diameter step portion 52b extending in the axial direction from the inner rolling surface 52a and the small-diameter step portion 52b of the hub wheel 52 are externally fitted to the double-row outer rolling surfaces 51a and 51b. An inner member 55 composed of an inner ring 54 formed with the other inner rolling surface 54a facing each other, double rows of balls 56, 57 accommodated between both rolling surfaces, and these double rows of balls 56, 57 A retainer 58 for freely rolling It is composed of a double row angular contact ball bearing with a 9.

  The inner ring 54 is fixed in the axial direction by a caulking portion 52c formed by plastically deforming a small diameter step portion 52b of the hub wheel 52 radially outward. Seals 60 and 61 are attached to the opening of the annular space formed between the outer member 51 and the inner member 55, leakage of the lubricating grease sealed inside the bearing, and rainwater from the outside into the bearing. And dust are prevented from entering.

  Here, the pitch circle diameter D1 of the outer side ball 56 is set larger than the pitch circle diameter D2 of the inner side ball 57. Along with this, the inner rolling surface 52a of the hub wheel 52 is expanded in diameter than the inner rolling surface 54a of the inner ring 54, and the outer rolling surface 51a on the outer side of the outer member 51 is also rolled on the inner side. The diameter is larger than that of the surface 51b. The outer side balls 56 are accommodated more than the inner side balls 57. In this way, by setting the pitch circle diameters D1 and D2 to D1> D2, the rigidity is improved not only when the vehicle is stationary but also when turning, and the life of the wheel bearing device 50 can be extended. it can.

JP 2004-108449 A

  In such a wheel bearing device 50, when the grease is sealed inside the bearing during manufacture of the bearing, as shown in FIG. 4, double rows of balls 56 and 57 are previously held by cages 58 and 59, and these ball cassettes are used. Is inserted into the outer member 51, and the grease sealing jig 62 is inserted (in the direction of the arrow in the figure) to enclose the grease. That is, a plurality of right and left nozzles 62a and 62b protruding in the radial direction of the grease sealing jig 62 are opposed to the ball cassette, and a predetermined amount of grease is sealed.

  However, in this type of left-right asymmetric wheel bearing device 50, a predetermined amount of grease is evenly sealed in the respective bearing rows, so that the inner space volumes of the inner side bearing row and the outer side bearing row are different. Thus, for example, in the inner bearing row having a small space volume, grease is sealed more than necessary with respect to the space volume. Thus, when the amount of grease filled increases, the occurrence of grease leakage during operation and the rotational torque may increase. Here, if grease leakage occurs, the braking effectiveness may be deteriorated, and an increase in rotational torque leads to a reduction in fuel consumption of the automobile.

  The present invention has been made in view of such circumstances, and provides a method for enclosing grease in a wheel bearing device that increases bearing rigidity and ensures optimum lubrication conditions to extend the life of the bearing. The purpose is that.

In order to achieve such an object, the method invention according to claim 1 of the present invention comprises an outer member having a double row outer rolling surface formed on the inner periphery, and an outer rolling surface of the double row formed on the outer periphery. An inner member provided with opposing double-row inner rolling surfaces, and a double-row rolling element accommodated in a freely rollable manner between the inner member and both rolling surfaces of the outer member, In the grease sealing method for a wheel bearing device in which the pitch circle diameter of the outer side rolling element of the double row rolling elements is set to be larger than the pitch circle diameter of the inner side rolling element, the rolling element and the holding In a state in which the double-row ball cassette composed of a container is fitted inside the outer member, a grease filling jig having a plurality of nozzles projecting radially is inserted, and the outer nozzle among the plurality of nozzles is inserted. diameter of the side nozzle is set to be larger in diameter than the diameter of the inner side nozzle, the The number of nozzles encapsulating amount of grease which is proportional to the internal space volume ratio of each bearing column of by facing the outer side and the inner side to the ball cassette.

As described above, the wheel bearing device of the first to fourth generation structures in which the pitch circle diameter of the outer side rolling elements of the double row rolling elements is set larger than the pitch circle diameter of the inner side rolling elements. In this grease filling method, a grease filling jig in which a plurality of nozzles project radially is inserted in a state where double row ball cassettes each consisting of a rolling element and a cage are respectively fitted in outer members. Of the plurality of nozzles is set to have a diameter larger than that of the inner nozzle, and the plurality of nozzles are opposed to the ball cassette so that the inner side of each of the outer and inner bearing rows Since the amount of grease proportional to the space volume ratio is enclosed, the pitch circle diameters of the double row rolling elements are different, and the optimum amount of grease can be secured even if the internal space volumes of the left and right bearing rows are different. Kill. Therefore, it is possible to provide a wheel bearing device that increases the bearing rigidity and ensures optimum lubrication conditions to extend the life of the bearing.

  Preferably, as in the invention described in claim 2, if the number of the outer side nozzles and the number of the inner side nozzles among the plurality of nozzles are different, the pitch circle diameters of the double row rolling elements respectively. Even if the inner space volume of the bearings on the left and right rows is different, the optimum amount of grease can be secured at the appropriate position, eliminating problems such as the occurrence of grease leakage and increased rotational torque during operation. be able to.

According to a third aspect of the present invention, a nozzle facing the double row ball cassette is integrally attached to the grease sealing jig, and the grease sealing jig is connected to the inner side from the outer side of the outer member. If it is inserted, interference with the components can be prevented and the grease filling jig can be inserted smoothly.

The method for enclosing grease in a wheel bearing device according to the present invention includes an outer member having a double row outer raceway formed on the inner periphery, and an inner side of the double row facing the outer raceway of the double row on the outer periphery. An inner member provided with a rolling surface; and a double-row rolling element that is rotatably accommodated between both rolling surfaces of the inner member and the outer member, the double-row rolling element. In the grease sealing method for a wheel bearing device in which the pitch circle diameter of the outer side rolling elements is set to be larger than the pitch circle diameter of the inner side rolling elements, a double row of the rolling elements and the cage is provided. With the ball cassette fitted inside the outer member, a grease filling jig having a plurality of nozzles projecting radially is inserted, and the diameter of the outer nozzle among the plurality of nozzles is set. than the diameter of the inner side nozzle is set to be larger in diameter, the plurality of nozzles The grease is sealed in an amount proportional to the internal space volume ratio of the outer and inner bearing rows facing the ball cassette, so that the pitch circle diameters of the double row rolling elements are different from each other. Even if the internal space volumes of the rows are different, the optimum amount of grease can be secured. Therefore, it is possible to provide a wheel bearing device that increases the bearing rigidity and ensures optimum lubrication conditions to extend the life of the bearing.

It is a longitudinal section showing one embodiment of a wheel bearing device concerning the present invention. It is explanatory drawing which shows the grease enclosure process of the wheel bearing apparatus of FIG. It is a longitudinal cross-sectional view which shows the conventional wheel bearing apparatus. It is explanatory drawing which shows a grease enclosure process same as the above.

A body mounting flange for mounting to the knuckle on the outer periphery is integrated, an outer member with a double row outer raceway formed on the inner periphery, and a wheel mounting flange for mounting the wheel on one end is integrated. A hub wheel having one inner rolling surface facing the outer rolling surface of the double row on the outer periphery, a small diameter step portion extending in the axial direction from the inner rolling surface, and a small diameter of the hub wheel An inner member consisting of an inner ring that is press-fitted into a stepped portion and has the other inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and both rolling of the inner member and the outer member A double row rolling element housed in a freely rolling manner between the surfaces, and the pitch circle diameter of the outer side rolling element of the double row rolling element is larger than the pitch circle diameter of the inner side rolling element. In the grease filling method for a wheel bearing device set to The number of the outer side rolling elements is set to be larger than the number of the inner side rolling elements, and a double row ball cassette comprising the rolling elements and the cage is used as the outer member. Inserting a grease filling jig in which a plurality of nozzles project radially, with each being fitted inside, the diameter of the nozzle on the outer side of the plurality of nozzles is larger than the diameter of the nozzle on the inner side A large diameter was set, and a predetermined amount of grease was sealed with the plurality of nozzles facing the ball cassette.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing an embodiment of a wheel bearing device according to the present invention, and FIG. 2 is an explanatory view showing a grease filling process of the wheel bearing device of FIG.

  This wheel bearing device is for a driven wheel referred to as a third generation, and is a double row rolling element housed in a freely rollable manner between the inner member 1 and the outer member 2, and both members 1 and 2. (Balls) 3 and 3. The inner member 1 includes a hub ring 4 and an inner ring 5 press-fitted into the hub ring 4 through a predetermined shimiro.

  The hub wheel 4 integrally has a wheel mounting flange 6 for mounting a wheel (not shown) at an end portion on the outer side, and has one (outer side) inner rolling surface 4a on the outer periphery and the inner rolling surface. A small-diameter step portion 4b is formed through a shaft-like portion 7 extending in the axial direction from the surface 4a. Hub bolts 6a are implanted in the wheel mounting flange 6 in a circumferentially equal distribution, and circular holes 6b are formed between the hub bolts 6a. The circular hole 6b can not only contribute to weight reduction, but also a fastening jig such as a wrench can be inserted from the circular hole 6b in the assembly / disassembly process of the apparatus, and the work can be simplified.

  The inner ring 5 is formed with the other (inner side) inner raceway surface 5a on the outer periphery and is press-fitted into the small-diameter stepped portion 4b of the hub wheel 4 to form a back-to-back type double row angular contact ball bearing. The inner ring 5 is fixed in the axial direction by a caulking portion 8 formed by plastic deformation of the end portion of 4b. The inner ring 5 and the rolling element 3 are made of high carbon chrome steel such as SUJ2, and are hardened in the range of 58 to 64 HRC to the core part by quenching.

  The hub wheel 4 is made of medium carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and the inner raceway surface 4a and the inner side base portion 6c of the wheel mounting flange 6 to the small diameter step portion 4b. Thus, the surface hardness is set to a range of 58 to 64 HRC by induction hardening. The caulking portion 8 is kept in the surface hardness after forging. Thereby, it has sufficient mechanical strength with respect to the rotational bending load applied to the wheel mounting flange 6, the fretting resistance of the small-diameter step portion 4b serving as the fitting portion of the inner ring 5 is improved, and the minute There is no occurrence of cracks and the like, and the plastic working of the caulking portion 8 can be performed smoothly.

  The outer member 2 integrally has a vehicle body mounting flange 2c to be attached to a knuckle (not shown) on the outer periphery, and the outer side outer rolling facing the inner rolling surface 4a of the hub wheel 4 on the inner periphery. The surface 2a and the inner side outer rolling surface 2b facing the inner rolling surface 5a of the inner ring 5 are integrally formed. Double-row rolling elements 3 and 3 are accommodated between these rolling surfaces and are held by the cages 9 and 10 so as to roll freely. This outer member 2 is formed of medium carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and the double row outer rolling surfaces 2a and 2b have a surface hardness in the range of 58 to 64HRC by induction hardening. Has been cured. Seals 11 and 12 are attached to the opening of the annular space formed between the outer member 2 and the inner member 1, and leakage of grease sealed inside the bearing and rainwater from the outside. And dust are prevented from entering the bearing. In addition, although the double row angular contact ball bearing which used the ball for the rolling element 3 was illustrated here, not only this but the double row tapered roller bearing which uses the tapered roller for the rolling element 3 may be sufficient. In addition, the first generation and second generation, or the fourth generation structure may be used instead of the third generation structure on the driven wheel side.

  In this embodiment, the pitch circle diameter PCDo of the outer side rolling element 3 is set larger than the pitch circle diameter PCDi of the inner side rolling element 3. The sizes of the double-row rolling elements 3 and 3 are the same, but due to the difference in pitch circle diameters PCDo and PCDi, the number of outer-side rolling elements 3 is set larger than the number of inner-side rolling elements 3. Has been.

  The outer shape of the hub wheel 4 is such that the counter portion 13 from the groove bottom portion of the inner rolling surface 4a, the shaft-like portion 7 extending in the axial direction from the counter portion 13 through the step portion 7a, and the shoulder to which the inner ring 5 is abutted. It continues to the small diameter step part 4b via the part 7b. A mortar-shaped recess 14 is formed at the outer end of the hub wheel 4. The depth of the recess 14 is a depth to the vicinity of the groove bottom of the inner rolling surface 4a, and the outer side of the hub wheel 4 has a substantially uniform thickness. Further, along with the difference between the pitch circle diameters PCDo and PCDi, the inner raceway surface 4a of the hub wheel 4 is formed to have a larger diameter than the inner raceway surface 5a of the inner race 5, and the outer diameter of the shaft portion 7 is inwardly rolled. The diameter is set to be substantially the same as the groove bottom diameter of the running surface 5a.

  On the other hand, in the outer member 2, the outer side outer rolling surface 2a is formed with a larger diameter than the inner side outer rolling surface 2b due to the difference in pitch circle diameters PCDo and PCDi, and the outer side outer rolling surface 2b is formed. From the running surface 2a through the cylindrical shoulder portion 15 and the step portion 15a to the shoulder portion 16 on the small diameter side, the outer rolling surface 2b on the inner side is reached.

  In the wheel bearing device having such a configuration, the pitch circle diameter PCDo of the outer side rolling element 3 is set larger than the pitch circle diameter PCDi of the inner side rolling element 3, and the number of the rolling elements 3 is also increased accordingly. Since the number of sides is set to be larger than the number of inner sides, it is possible to effectively increase the bearing rigidity of the outer side compared to the inner side by utilizing the bearing space, and to extend the life of the bearing. Can do. Furthermore, since the recess 14 is formed along the outer shape at the outer end of the hub wheel 4 and the outer side of the hub wheel 4 is set to a uniform thickness, the device is lighter, more compact and more rigid. It is possible to solve the conflicting problem.

  Here, the amount of grease filled is proportional to the internal space volume ratio of the left and right bearing rows. That is, grease in the range of 40 to 60%, preferably 45 to 55% with respect to the outer side total space volume is enclosed in the outer side bearing row and 40% with respect to the inner side total space volume. ~ 60%, preferably 45 to 55% of grease is enclosed in the inner bearing row. Furthermore, the right and left weight variation of the grease to be enclosed is regulated to be within ± 20%. The total space volume on the outer side and the inner side means the total space volume from the center of the pitch of the double row rolling elements 3 and 3 to the bearing inner side of each of the outer seal 11 and the inner seal 12. .

  As shown in FIG. 2, the grease is filled in a state where the double-row rolling elements 3 and 3 are held in advance by the cages 9 and 10 and these ball cassettes are fitted in the outer member 2 as shown in FIG. The jig 17 is inserted (in the direction of the arrow in the figure) to enclose the grease. That is, a plurality of right and left nozzles 17a and 17b projecting in the radial direction of the grease filling jig 17 are opposed to the ball cassette, and an amount of grease proportional to the internal space volume ratio of the outer and inner bearing rows. Is enclosed.

  Here, the diameter do of the nozzle 17a facing the outer bearing row where the pitch circle diameter PCDo is large is larger than the diameter di of the nozzle 17b facing the inner bearing row, and the area ratio is It is set to be the bearing internal space volume ratio of the row. As a result, even when the pitch circle diameters PCDo and PCDi of the double-row rolling elements 3 and 3 are different, and the bearing internal space volumes of the left and right rows are different, an optimal amount of grease can be secured. Therefore, it is possible to eliminate the problem that grease leakage occurs during operation and the rotational torque increases.

  In the present embodiment, the diameters do and di of the outer side and inner side nozzles 17a and 17b are changed to enclose a predetermined amount of grease, but the present invention is not limited to this. However, the grease filling amount may be adjusted by changing the number of the outer side and inner side nozzles 17a, 17b.

  The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including.

  The grease sealing method for a wheel bearing device according to the present invention can be applied to a wheel bearing device having a first to fourth generation structure regardless of whether it is for a driving wheel or a driven wheel.

1 ... Inner member 2 ... Outer member 3 ... Rolling element 4 ... Hub wheel 4a, 5a ... Inner rolling surface 4b ... Small diameter step 5 ... Inner ring 6 ... Wheel mounting flange 6a ················································ 6 7b, 15,16 ... Shoulder 8 ... Clamping part 9,10 ... Cage 11,12 ... Seal 13 ... ················································································ Grease filling jigs 17a, 17b .... Outer member 51a ... On the outer side Side rolling surface 51b ... Outer side rolling surface 51c on the inner side ... Body mounting flange 52 ... Hub wheels 52a, 54a ... Inside rolling Surface 52b ... Small diameter step 52c ... Clamping part 53 ... Wheel mounting flange 54 ... Inner ring 55 ... ..... Inward members 56, 57 ... Balls 58, 59 ... Retainer 60, 61 ... Seal 62 ...... Grease filling jig 62a, 62b... Nozzle D1... Pitch pitch diameter D2 of outer side ball... Pitch pitch diameter di of inner side ball di, do. PCDi ... Pitch circle diameter of inner side ball PCDo ... Pitch circle diameter of outer side ball

Claims (3)

An outer member having a double row outer raceway formed on the inner periphery;
An inner member provided with a double row inner raceway facing the outer circumference of the double row on the outer periphery;
A double row rolling element housed in a freely rolling manner between the rolling surfaces of the inner member and the outer member;
In the grease sealing method of the wheel bearing device in which the pitch circle diameter of the outer side rolling elements of the double row rolling elements is set larger than the pitch circle diameter of the inner side rolling elements,
In a state where the double row ball cassettes composed of the rolling elements and the cage are respectively fitted into the outer members, a grease sealing jig having a plurality of nozzles protruding radially is inserted, and the plurality of the ball cassettes are inserted. Of the outer side nozzle is set to be larger than the diameter of the inner side nozzle, and the inner space volume of each of the outer and inner side bearing rows with the plurality of nozzles facing the ball cassette A grease sealing method for a wheel bearing device, characterized in that an amount of grease proportional to the ratio is sealed.   The method for enclosing grease in a wheel bearing device according to claim 1, wherein the number of outer side nozzles and the number of inner side nozzles among the plurality of nozzles are different. The wheel bearing according to claim 1 or 2, wherein a nozzle facing the double row ball cassette is integrally attached to the grease sealing jig, and the grease sealing jig is inserted from an outer side of the outer member. How to grease the equipment.

Images