WO2003074890A1 - Rolling bearing unit for supporting wheel - Google Patents

Rolling bearing unit for supporting wheel Download PDF

Info

Publication number
WO2003074890A1
WO2003074890A1 PCT/JP2003/002370 JP0302370W WO03074890A1 WO 2003074890 A1 WO2003074890 A1 WO 2003074890A1 JP 0302370 W JP0302370 W JP 0302370W WO 03074890 A1 WO03074890 A1 WO 03074890A1
Authority
WO
WIPO (PCT)
Prior art keywords
rolling bearing
bearing unit
seal
wheel
raceway
Prior art date
Application number
PCT/JP2003/002370
Other languages
French (fr)
Japanese (ja)
Inventor
Junshi Sakamoto
Original Assignee
Nsk Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nsk Ltd. filed Critical Nsk Ltd.
Priority to AU2003211541A priority Critical patent/AU2003211541A1/en
Publication of WO2003074890A1 publication Critical patent/WO2003074890A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B27/00—Hubs
    • B60B27/0073—Hubs characterised by sealing means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B27/00—Hubs
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B27/00—Hubs
    • B60B27/0005—Hubs with ball bearings
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B27/00—Hubs
    • B60B27/0078—Hubs characterised by the fixation of bearings
    • B60B27/0084—Hubs characterised by the fixation of bearings caulking to fix inner race
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B27/00—Hubs
    • B60B27/0094—Hubs one or more of the bearing races are formed by the hub
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
    • F16C33/72—Sealings
    • F16C33/76—Sealings of ball or roller bearings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C19/00—Bearings with rolling contact, for exclusively rotary movement
    • F16C19/02—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows
    • F16C19/14—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for both radial and axial load
    • F16C19/18—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for both radial and axial load with two or more rows of balls
    • F16C19/181—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for both radial and axial load with two or more rows of balls with angular contact
    • F16C19/183—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for both radial and axial load with two or more rows of balls with angular contact with two rows at opposite angles
    • F16C19/184—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for both radial and axial load with two or more rows of balls with angular contact with two rows at opposite angles in O-arrangement
    • F16C19/186—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for both radial and axial load with two or more rows of balls with angular contact with two rows at opposite angles in O-arrangement with three raceways provided integrally on parts other than race rings, e.g. third generation hubs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C2326/00—Articles relating to transporting
    • F16C2326/01—Parts of vehicles in general
    • F16C2326/02—Wheel hubs or castors

Definitions

  • the present invention relates to an improvement in a rolling bearing unit for supporting a wheel for rotatably supporting a wheel with respect to a suspension system of an automobile. Background technology
  • FIGS. 11 Japanese Patent Application Laid-Open No. 2001-221234 discloses a structure as shown in FIGS. First, the structure of the first example shown in FIG. 11 will be described.
  • a wheel 1 constituting a wheel is rotatably supported on an end of an axle 3 constituting a suspension by a rolling bearing unit 2 for supporting a wheel. That is, the inner races 5, which are stationary raceways, constituting the wheel supporting rolling bearing unit 2, are externally fitted to the support shaft 4 fixed to the end of the axle 3, and fixed by the nut 6.
  • the wheel 1 is fixedly connected to a hub 7, which is a rotating raceway, constituting the wheel supporting rolling bearing unit 2 by a plurality of studs 8, 8 and nuts 9, 9.
  • double-row outer ring raceways 10a and 10b are formed, and on the outer peripheral surface, a mounting flange 11 is formed.
  • the above-mentioned wheel 1 is provided with the above-mentioned studs 8 and 8 and nuts 9 and 9 on one side (the outer side in the illustrated example) of the above-mentioned mounting flange 11 together with the drum 12 and the drum for constituting the braking device. Due to this, the connection is fixed.
  • Seal rings 16a and 16b are provided between the inner peripheral surfaces at both ends of the hub 7 and the outer peripheral surfaces at the ends of the inner rings 5 and 5, respectively. It blocks the space with 14 and the outside space.
  • the outer end of the hub 7 (the term “outside in the axial direction” refers to the outer side in the width direction when assembled to the vehicle. Similarly, the center side in the width direction is referred to as "in”. The same applies throughout the present specification.) Closed by cap 17.
  • the support shaft 4 having the inner rings 5 and 5 externally fixed thereto is fixed to the axle 3 and the mounting flange 1 of the hub 7 is fixed.
  • a drum drum for braking is configured by combining the drum 12 of these with a wheel cylinder and a shoe (not shown) supported on a backing plate 18 fixed to the end of the axle 3. At the time of braking, a pair of shoes provided on the inner diameter side of the drum 12 is pressed against the inner peripheral surface of the drum 12.
  • a hub 7a as a rotating raceway is provided on the inner diameter side of an outer ring 19 as a stationary raceway, and a plurality of balls each being a rolling element. It is supported rotatably by 14 and 14.
  • the double-row outer raceways 10a and 10b are rotated on the inner circumferential surface of the outer race 19, respectively, on the outer circumferential surface of the hub 7a.
  • First and second inner raceways 20 and 21 which are side raceway surfaces are provided, respectively.
  • the hub 7a is formed by combining a hub body 22 and an inner ring 23.
  • the mounting flange 11 a for supporting the wheel is also provided, the first inner raceway 20 is also provided at the intermediate portion, and the inner end track is also provided at the intermediate portion.
  • the small-diameter step portions 24 each having a smaller diameter than the portion where the first inner ring raceway 20 is formed are provided.
  • the inner ring 23 provided with the second inner ring raceway 21 having an arc-shaped cross section on the outer peripheral surface is externally fitted to the small-diameter stepped portion 24.
  • the inner end surface of the inner ring 23 is suppressed by a caulking portion 25 formed by plastically deforming the inner end portion of the hub body 22 radially outward, and the inner ring 23 is attached to the hub body 22. On the other hand, it is fixed. Further, seal rings 16c and 16d are provided between inner peripheral surfaces of both ends of the outer ring 19, an outer peripheral surface of an intermediate portion of the hub 7a, and an outer peripheral surface of an inner end of the inner ring 23, respectively. The balls 14 and 14 are set between the inner peripheral surface of the outer ring 19 and the outer peripheral surface of the hub 7a. It shields the girder space from the outside space.
  • seal rings 16a, 16b (or 1a) are used to close the openings at both ends of the internal space where the balls 14, 14 are installed. Due to the existence of 6c, 16d), it is inevitable that the torque required for rotating the hub 7 (or 7a) (rotational resistance of the rolling bearing unit for wheel support) increases. As a result, the driving performance of the vehicle incorporating the above-mentioned rolling bearing unit for supporting the wheel, particularly the acceleration performance and the fuel consumption performance, is deteriorated. Therefore, in response to the recent trend of energy saving, improvement is desired. I have.
  • the rolling bearing unit for supporting wheels of the present invention has been invented in view of such circumstances. Disclosure of the invention
  • the rolling bearing unit for supporting a wheel according to the present invention includes a stationary bearing ring, a rotating bearing ring, and a plurality of balls, as in the above-described conventionally known rolling bearing unit for supporting a wheel. And a seal ring.
  • the stationary race is supported and fixed to the suspension device in use.
  • the rotating raceway rings support and fix the wheels in use.
  • the balls are provided between the stationary raceway and the rotating raceway, each having an arc-shaped cross section, which are present on the peripheral surfaces of the stationary raceway and the rotating raceway facing each other. Have been killed.
  • the pair of seal rings close both end openings of the space in which the balls are installed between the opposing peripheral surfaces of the stationary raceway ring and the rotating raceway ring.
  • Each of the two seal rings has two to three seal lips, each of which is made of an elastic material.
  • the axial load for applying a preload to each of the balls is 0.49 to 2.94 kN (50 to 300 kgf).
  • the stationary raceway and the rotating raceway are relatively rotated at 20 Omin- 1 based on the rolling resistance of each ball.
  • the required torque (rolling resistance) is 0.12 to 0.23N • m.
  • the rigidity coefficient is 0.09 or more when the axial load is 1.96 kN.
  • the torque required to rotate the stationary raceway and the rotating raceway relative to each other at 20 Omin- 1 based on the friction between each seal lip and the mating surface is 0 in total for both seal rings. 06 ⁇ 0.4N'm.
  • the stiffness coefficient described in this specification is the stiffness R [kN ⁇ m / deg] of the wheel-supporting rolling bearing unit, and the radial dynamic load rating of the wheel-supporting rolling bearing unit. It is the ratio (RZC r) to C r [N].
  • the rigidity R in this case is the above-mentioned rigidity when the momentary load is applied to the rotating raceway while the stationary raceway constituting the wheel supporting rolling bearing unit is fixed. Raceway It is expressed by the angle of inclination, and is measured, for example, as shown in FIG. FIG. 13 shows a state where the rigidity R of the wheel supporting rolling bearing unit 2a shown in FIG. 12 is measured.
  • the outer ring 19, which is the stationary raceway, is fixed to the upper surface of the fixed base 37, and the base end of the lever plate 38 is attached to the mounting flange 11a of the hub 7a, which is the rotating raceway (Fig. 13). (The left end). Then, a load is applied to a portion of the upper surface of the lever plate 38, which is separated from the rotation center of the above-mentioned bracket 7a by a distance L corresponding to the rotation radius of the tire, and the hub 7a is provided via the lever plate 38. A moment load of 1.5 kN'm.
  • the inclination angle is determined by the inclination angle [deg] of the mounting surface 40 of the mounting flange 11a with respect to the upper surface 39 of the fixed base 37.
  • the rigidity R [kN-m / deg] is obtained by dividing the moment load (1.5 kN, m) by this inclination angle.
  • the rigidity coefficient is obtained by dividing the rigidity R by the radial dynamic load rating Cr [N] of the wheel supporting rolling bearing unit 2a.
  • the rotating torque can be sufficiently reduced while securing the required rigidity and durability.
  • the axial load for applying the preload is 0.49 kN or more
  • the rolling resistance when this axial load is 1.96 kN is 0.12 Nm or more
  • the Oka IJ coefficient is 0.09 or more.
  • the axial load for applying the preload is 2.94 kN or less
  • the rolling resistance is 0.23 N ⁇ m or less
  • the total rotational resistance (torque) of a pair of seal rings is 0. . 4N'm or less, so the above-mentioned rotation torque can be reduced.
  • the rolling resistance cannot be suppressed to a low level (for example, 0.23 0 ⁇ ⁇ or less), and the rotational torque cannot be reduced.
  • the axial load is less than 0.49 kN, it becomes difficult to secure the rigidity of the wheel supporting rolling unit unit. As a result, steering stability decreases.
  • the rotational torque of the entire wheel supporting rolling unit can be reduced.
  • the total rotational resistance of the two seal rings is maintained at 0.06 ⁇ ⁇ ⁇ or more, the required sealing performance (mainly, muddy water resistance to prevent intrusion of muddy water) can be ensured.
  • the axial load for applying the preload is 0.49 to 2.94 kN, and the rolling resistance when this axial load is 1.96 kN is 0.12 to 0.23 Nm, Similarly, in the case of the rolling bearing unit for supporting a wheel of the present invention in which the rigidity coefficient is 0.09 or more and the rotational resistance of both seal rings is 0.06 to 0.4 Nm in total, rigidity and durability are secured. While reducing the rotational torque.
  • FIG. 1 is a sectional view showing a first example of a structure to which the present invention is applied.
  • FIG. 2 is a cross-sectional view showing a second example of the structure to which the present invention is applied.
  • FIG. 3 is a cross-sectional view showing a third example of the structure to which the present invention is applied.
  • FIG. 4 is a partial cross-sectional view showing a first example of a specific structure of a seal ring applicable to the present invention.
  • FIG. 5 is a partial cross-sectional view showing a second example of the specific structure of the seal ring applicable to the present invention.
  • FIG. 6 is a partial cross-sectional view showing a third example of the specific structure of the seal ring applicable to the present invention.
  • FIG. 7 is a partial sectional view showing a fourth example of the specific structure of the seal ring applicable to the present invention.
  • FIG. 8 is a partial cross-sectional view showing a fifth example of the specific structure of the seal ring applicable to the present invention.
  • FIG. 9 is a partial cross-sectional view showing a sixth example of the specific structure of the seal ring applicable to the present invention.
  • FIG. 10 is a partial sectional view showing a seventh example of the specific structure of the seal ring applicable to the present invention.
  • FIG. 11 is a cross-sectional view showing a first example of a conventionally known wheel-supporting rolling bearing unit when assembled to a suspension device.
  • FIG. 12 is a cross-sectional view showing a second example of a conventionally known rolling bearing unit for supporting a wheel.
  • FIG. 13 is a cross-sectional view showing a state in which the rigidity of the wheel supporting rolling bearing unit is measured.
  • a rolling bearing unit for supporting a wheel which is an object of the present invention.
  • the present invention is also applicable to the structure shown in FIGS. 11 and 12 described above.
  • the first and second examples described below apply the present invention to driving wheels (FR wheels, rear wheels, FF vehicles). It shows the case where the present invention is applied to a rolling bearing unit for supporting a wheel for rotatably supporting the front wheel of the vehicle and all wheels of a 4WD vehicle).
  • the present invention is particularly important as a wheel supporting rolling bearing unit for driving wheels. The reason for this is shown in Figs. 11 and 12 above.
  • a rolling bearing unit for supporting wheels such as driven wheels (front wheels of FR vehicles, rear wheels of FF vehicles)
  • the raceway wheels located on the outer diameter side (Fig.
  • the seal ring (16a, 16d) on one end side is omitted by closing one end opening of the outer ring 19) with the cap 17 (Fig. 11), and only one seal ring that generates sliding resistance
  • two seal rings are required.
  • a plurality of hubs 7b which are rotating-side races, are provided on the inner diameter side of the outer race 19, which is a stationary-side race. It is rotatably supported by balls 14 and 14.
  • a spline hole 26 for inserting a spline shaft (not shown) attached to the constant velocity joint is formed in the center of the hub body 22a constituting the hub 7b.
  • the inner end surface of the inner ring 23 externally fitted to the small-diameter step portion 24 formed at the inner end of the hub body 22a is formed by plastically deforming the inner end of the hub body 22a radially outward.
  • the inner ring 23 is fixed to the hub main body 22a by being held down by the caulking portion 25, thereby forming the hub 7b.
  • Seal rings 16 c and 16 d are provided between the inner peripheral surfaces of both ends of the outer ring 19, the outer peripheral surface of the intermediate portion of the hub body 22 a, and the outer peripheral surface of the inner end of the inner ring 23, respectively. Between the inner peripheral surface of the outer ring 19 and the outer peripheral surface of the hub 7b, the space in which the balls 14, 14 are provided and the outer space are shut off.
  • the balls 14, 14 The axial load for applying a preload to 14 shall be 0.49 to 2.94 kN.
  • the torque (rolling resistance) required to rotate the hub 7b at 20 Omin- 1 inside the outer ring 19 is 0.12 to 0.23N '. m.
  • the stiffness coefficient when this axial load is 1.96 kN is set to 0.09 or more.
  • the total rotational resistance (torque) of the two seal rings 16c and 16d is restricted to a range of 0.06 to 0.4Nm.
  • the seal rings 16c and 16d The structure of the other parts is the same as the structure shown in FIG.
  • the hub 7c is formed together with the hub main body 2 2b by externally fitting the small-diameter step portion 24 provided at the inner end of the hub main body 22b.
  • the inner end surface of the inner ring 23 protrudes more inward than the inner end surface of the hub body 22 b.
  • the outer end surface of the constant velocity joint (not shown) abuts on the inner end surface of the inner ring 23 in a state where the inner ring 23 is mounted on the vehicle, thereby preventing the inner ring 23 from falling off the small diameter step portion 24.
  • the axial load for applying the preload is adjusted by the tightening torque of the nut screwed to the outer end of the spline shaft (not shown).
  • Other configurations are the same as those in the first example shown in FIG. 1 described above.
  • the present invention is applied to a case where the present invention is applied to a rolling bearing unit for rotatably supporting a driven wheel as shown in FIG. 11 described above.
  • a rolling bearing unit for rotatably supporting a driven wheel as shown in FIG. 11 described above.
  • the first inner ring raceway 20 is formed directly in the middle part, and the outer end surface of the inner ring 5 is held down by a caulking part 25 formed by plastically deforming the outer end of the support shaft 4a radially outward.
  • the inner ring 5 is fixed to the support shaft 4a.
  • the axial load for applying the preload is adjusted by the load at the time of processing the caulked portion 25.
  • the structure of the other parts is the same as that of the first example described above and the structure shown in FIG.
  • FIGS. 4 to 8 are the first to third examples of the wheel-supporting rolling unit shown in FIGS. 1 to 3 and the structures of FIGS.
  • the first example shown in FIG. 4 includes an outer-diameter-side seal ring 27 that is internally fitted and fixed to the inner end of an outer ring 19 (FIGS. 1 and 2), and an inner ring 23 (FIGS. 1 and 2).
  • This is a combination seal ring combining an inner diameter side seal ring 28 that is externally fitted and fixed to the end, and has a total of three seal lips, two on the inner diameter side and one on the outer diameter side.
  • FIG. 5 a second example shown in FIG. 5 is a seal ring 29 that is fitted and fixed to the inner end of the outer ring 19 (FIGS. 1 and 2), and an inner end of the inner ring 23 (FIGS. 1 and 2).
  • This is a combination seal ring in which a slinger 30 that is externally fitted and fixed to the seal ring is used. With book seal lip.
  • FIG. 7 shows a seal ring 33a which is locked to the inner peripheral surface of the inner end of the outer ring 19 (FIGS. 1 and 2), and an inner end of the inner ring 23 (FIGS. 1 and 2).
  • This is a combination seal ring combining the seal ring 33b which is locked to the outer peripheral surface.
  • a total of three seal lips are provided, two on the seal ring 33a locked on the outer ring 19 side and one on the seal ring 33b locked on the inner ring 23 side.
  • FIG. 8 shows the front edges of the two seal lips provided on the seal ring 34 fitted inside the inner end of the outer ring 19 (FIGS. 1 and 2), and the inner end of the inner ring 23 (FIGS. 1 and 2). This is to make sliding contact with the outer peripheral surface.
  • Figs. 9 and 10 show the inner peripheral surface of the outer end of the outer ring 19 (Figs. 1-2) and the outer peripheral surface of the intermediate part of the hub bodies 22a (Fig. 1) and 22b (Fig.
  • the figure shows a structure that can be used as a sealing provided between them.
  • the seal ring 35 of the first example shown in FIG. 9 is provided with three seal lips on a core metal that can be fitted and fixed at the outer end of the outer ring 19. Can be slidably contacted with the inner surface of the mounting flange 11a (FIGS. 1 and 2) or a curved surface portion connecting the inner surface to the outer peripheral surfaces of the hub bodies 22a and 22b.
  • the middle seal lip 36 of the three seal lips provided on the seal ring 35a is connected to the hub body 22 by the girder spring 32a. a (Fig. 1) and 22b (Fig. 2).
  • a pair of seal rings selected from those shown in FIGS. 4 to 10 are used for the outer ring 19 (FIGS. 1 and 2) which constitutes the wheel supporting rolling bearing unit shown in FIGS. ,
  • Balls 14 and 14 are installed by assembling between the surface (Figs. Close the openings at both ends of the space. Then, regardless of which seal ring is combined, the total rotational resistance of both seal rings is restricted to the range of 0.06 to 0.4N'm. Also, ensure that the rotational resistance of the seal ring with the lower rotational resistance is at least 0.03 N 'm.
  • each seal ring was assembled into a wheel supporting rolling bearing unit shown in FIG. 1 or FIG. 3 and subjected to a muddy water intrusion test.
  • Lubrication of the wheel supporting rolling bearing Interview two Tsu DOO is performed by a viscosity encapsulating grease 10 X 10- 6 ⁇ 14X 10- 6 m 2 / s (10 ⁇ 14c S t), 20 ° C environment Below, the hub 7b (or 7) was rotated at 20 Omin " 1 .
  • Table 1 shows the results of the experiment performed under such conditions.
  • the circled numbers represent the drawing numbers describing the seal rings.
  • 4 indicates the seal ring shown in FIG. 4
  • 9 indicates the seal ring shown in FIG. 9, respectively.
  • 4 + ⁇ ⁇ ⁇ ⁇ ⁇ indicates that the seal ring shown in FIG. 4 and the seal ring shown in FIG. 9 are combined.
  • ⁇ XJ mark '' means that a large amount of muddy water has infiltrated the internal space filled with grease
  • ⁇ ⁇ '' means that a small amount of muddy water has entered
  • ⁇ ⁇ '' means that no infiltration of muddy water has been observed.
  • FIG. 1 Tables 2 to 5 show the results of the second to fifth experiments in which the seal ring shown in Fig. 4 and the seal ring shown in Fig. 9 were incorporated into the rolling bearing unit for wheel support shown in Fig. 4. It will be described with reference to FIG.
  • Table 2 shows the results of a second experiment conducted to find out the effect of the sealing torque on the rotation torque and durability of the entire rolling bearing unit. This experiment was performed at a rotation speed of 20 Omiir 1 .
  • Table 3 shows the results of a third experiment performed to determine the effect of the axial load (preload) on the stiffness of the rolling bearing unit and the overall rotational torque.
  • Table 4 shows the results of a fourth experiment performed to determine the effect of the rolling resistance on the rigidity of the rolling bearing unit and the overall rotational torque. This experiment was performed with an axial load (preload) of 1.96 kN (200 kgf) and a rotation speed of 20 Omin-.
  • Table 5 shows the results of a fifth experiment conducted to determine the effect of the rigidity coefficient on the rigidity of the rolling bearing unit. This experiment was performed with an axial load of 1.96 kN (20 Okgf) applied.
  • Table 6 shows the results of an experiment conducted to find out the effect of the sealing torque and the rolling resistance on the rotation torque of the rolling bearing unit as a whole.
  • an axial load of 1.96 kN (200 kgf) was applied, and the rotation speed was 20 O min-.
  • the rolling bearing unit for supporting a wheel according to the present invention is configured and operates as described above, the steering torque and the rotating torque of the hub that rotates with the wheel are reduced while maintaining the steering stability and durability, thereby improving the acceleration performance. However, it can contribute to the improvement of the running performance of vehicles mainly on fuel efficiency.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Rolling Contact Bearings (AREA)
  • Mounting Of Bearings Or Others (AREA)
  • Sealing Of Bearings (AREA)
  • Support Of The Bearing (AREA)

Abstract

A rolling bearing unit for supporting a wheel, wherein both end openings of a space having balls (14) and (14) installed therein are closed by seal rings (16c) and (16d) having two to three seal lips, a rolling resistance varying based on a pre-load is limited to the range of 0.12 to 0.23 N·m, and the total of the rolling resistances of both seal rings (16c) and (16d) based on the friction of the seal lips with their mating surfaces is limited to the range of 0.06 to 0.4 N·m, whereby the traveling performances of a vehicle mainly comprising an acceleration performance and a fuel consumption performance can be increased by reducing the torque of a hub rotating together with the wheel while assuring a steering stability.

Description

明細書 車輪支持用転がり軸受ュニッ卜 技術分野  Description Rolling bearing unit for wheel support Technical field
この発明は、 自動車の懸架装置に対して車輪を回転自在に支持する為の、 車輪 支持用転がり軸受ュニッ卜の改良に関する。 背景の技術  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a rolling bearing unit for supporting a wheel for rotatably supporting a wheel with respect to a suspension system of an automobile. Background technology
車輪支持用転がり軸受ユニットとして、 例えば特開 2 0 0 1— 2 2 1 2 4 3号 公報には、 図 1 1〜 1 2に示す様な構造が記載されている。 先ず、 このうちの図 1 1に示した第 1例の構造に就いて説明する。 車輪を構成するホイ一ル 1は、 車 輪支持用転がり軸受ユニット 2により、 懸架装置を構成する車軸 3の端部に回転 自在に支持している。 即ち、 この車軸 3の端部に固定した支持軸 4に、 上記車輪 支持用転がり軸受ユニット 2を構成する、 静止側軌道輪である内輪 5、 5を外嵌 し、 ナット 6により固定している。 一方、 上記車輪支持用転がり軸受ユニット 2 を構成する、 回転側軌道輪であるハブ 7に上記ホイール 1を、 複数本のスタッド 8、 8とナット 9、 9とにより結合固定している。  As a wheel supporting rolling bearing unit, for example, Japanese Patent Application Laid-Open No. 2001-221234 discloses a structure as shown in FIGS. First, the structure of the first example shown in FIG. 11 will be described. A wheel 1 constituting a wheel is rotatably supported on an end of an axle 3 constituting a suspension by a rolling bearing unit 2 for supporting a wheel. That is, the inner races 5, which are stationary raceways, constituting the wheel supporting rolling bearing unit 2, are externally fitted to the support shaft 4 fixed to the end of the axle 3, and fixed by the nut 6. . On the other hand, the wheel 1 is fixedly connected to a hub 7, which is a rotating raceway, constituting the wheel supporting rolling bearing unit 2 by a plurality of studs 8, 8 and nuts 9, 9.
上記ハブ 7の内周面には、 それぞれが回転側軌道面である複列の外輪軌道 1 0 a、 1 0 bを、 外周面には取付フランジ 1 1を、 それぞれ形成している。 上記ホ ィ一ル 1は、 制動装置を構成する為のドラム 1 2と共に、 上記取付フランジ 1 1 の片側面 （図示の例では外側面） に、 上記各スタッド 8、 8とナツ卜 9、 9とに より、 結合固定している。  On the inner peripheral surface of the hub 7, double-row outer ring raceways 10a and 10b, each of which is a rotating raceway surface, are formed, and on the outer peripheral surface, a mounting flange 11 is formed. The above-mentioned wheel 1 is provided with the above-mentioned studs 8 and 8 and nuts 9 and 9 on one side (the outer side in the illustrated example) of the above-mentioned mounting flange 11 together with the drum 12 and the drum for constituting the braking device. Due to this, the connection is fixed.
上記各外輪軌道 1 0 a、 1 0 と、 上記各内輪 5、 5の外周面に形成した、 そ れぞれが静止側軌道面である各内輪軌道 1 3、 1 3との間には、 玉 1 4、 1 4を 複数個ずつ、 それぞれ保持器 1 5、 1 5により保持した状態で転動自在に設けて いる。 構成各部材をこの様に組み合わせる事により、 背面組み合わせである複列 アンギユラ型の玉軸受を構成し、 上記各内輪 5、 5の周囲に上記ハブ 7を、 回転 自在に、 且つ、 ラジアル荷重及びスラスト荷重を支承自在に支持している。 尚、 JP03/02370 Between each of the outer raceways 10a, 10 and the inner raceways 13, 13 formed on the outer peripheral surface of each of the inner races 5, 5, each of which is a stationary raceway surface, A plurality of balls 14 and 14 are provided so as to roll freely while being held by cages 15 and 15 respectively. By combining the constituent members in this way, a double-row angular contact type ball bearing, which is a back-to-back combination, is configured. The hub 7 is rotatably mounted around each of the inner rings 5, and the radial load and thrust. The load is supported freely. still, JP03 / 02370
2 上記ハブ 7の両端部内周面と、 上記各内輪 5、 5の端部外周面との間には、 それ ぞれシールリング 1 6 a、 1 6 bを設けて、 上記各玉 1 4、 1 4を設けた空間と 外部空間とを遮断している。 更に、 上記ハブ 7の外端 （軸方向に関して外とは、 車両への組み付け状態で幅方向外側を言う。 同じく、 幅方向中央側を内と言う。 本明細書全体で同じ。 ） 開口部は、 キャップ 1 7により塞いでいる。  2 Seal rings 16a and 16b are provided between the inner peripheral surfaces at both ends of the hub 7 and the outer peripheral surfaces at the ends of the inner rings 5 and 5, respectively. It blocks the space with 14 and the outside space. Further, the outer end of the hub 7 (the term "outside in the axial direction" refers to the outer side in the width direction when assembled to the vehicle. Similarly, the center side in the width direction is referred to as "in". The same applies throughout the present specification.) Closed by cap 17.
上述の様な車輪支持用転がり軸受ユニット 2の使用時には、 図 1 1に示す様に、 内輪 5、 5を外嵌固定した支持軸 4を車軸 3に固定すると共に、 ハブ 7の取付フ ランジ 1 1に、 図示しないタイヤを組み合わせたホイール 1及びドラム 1 2を固 定する。 又、 このうちのドラム 1 2と、 上記車軸 3の端部に固定のバッキングプ レート 1 8に支持した、 図示しないホイルシリンダ及びシユーとを組み合わせて、 制動用のドラムブレーキを構成する。 制動時には、 上記ドラム 1 2の内径側に設 けた 1対のシユーをこのドラム 1 2の内周面に押し付ける。  When the rolling bearing unit 2 for wheel support as described above is used, as shown in FIG. 11, the support shaft 4 having the inner rings 5 and 5 externally fixed thereto is fixed to the axle 3 and the mounting flange 1 of the hub 7 is fixed. Fix wheel 1 and drum 12 with tires (not shown) to 1. Also, a drum drum for braking is configured by combining the drum 12 of these with a wheel cylinder and a shoe (not shown) supported on a backing plate 18 fixed to the end of the axle 3. At the time of braking, a pair of shoes provided on the inner diameter side of the drum 12 is pressed against the inner peripheral surface of the drum 12.
次に、 図 1 2に示した従来構造の第 2例に就いて説明する。 この車輪支持用転 がり軸受ユニット 2 aの場合には、 静止側軌道輪である外輪 1 9の内径側に、 回 転側軌道輪であるハブ 7 aを、 それぞれが転動体である複数の玉 1 4、 1 4によ り、 回転自在に支持している。 この為に、 上記外輪 1 9の内周面にそれぞれが静 止側軌道面である複列の外輪軌道 1 0 a、 1 0 bを、 上記ハブ 7 aの外周面にそ れぞれが回転側軌道面である第一、 第二の内輪軌道 2 0、 2 1を、 それぞれ設け ている。 このハブ 7 aは、 ハブ本体 2 2と内輪 2 3とを組み合わせて成る。 この うちのハブ本体 2 2の外周面の外端部に車輪を支持する為の取付フランジ 1 1 a を、 同じく中間部に上記第一の内輪軌道 2 0を、 同じく中間部内端寄り部分にこ の第一の内輪軌道 2 0を形成した部分よりも小径である小径段部 2 4を、 それぞ れ設けている。 そして、 この小径段部 2 4に、 外周面に断面円弧状である上記第 二の内輪軌道 2 1を設けた上記内輪 2 3を外嵌している。 更に、 上記ハブ本体 2 2の内端部を径方向外方に塑性変形させて成るかしめ部 2 5により上記内輪 2 3 の内端面を抑え付けて、 この内輪 2 3を上記ハブ本体 2 2に対し固定している。 更に上記外輪 1 9の両端部内周面と、 上記ハブ 7 aの中間部外周面及び上記内輪 2 3の内端部外周面との間に、 それぞれシールリング 1 6 c、 1 6 dを設けて、 上記外輪 1 9の内周面と上記ハブ 7 aの外周面との間で上記各玉 1 4、 1 4を設 けた空間と、 外部空間とを遮断している。 Next, a second example of the conventional structure shown in FIG. 12 will be described. In the case of this wheel supporting rolling bearing unit 2a, a hub 7a as a rotating raceway is provided on the inner diameter side of an outer ring 19 as a stationary raceway, and a plurality of balls each being a rolling element. It is supported rotatably by 14 and 14. For this purpose, the double-row outer raceways 10a and 10b, each of which is a stationary raceway surface, are rotated on the inner circumferential surface of the outer race 19, respectively, on the outer circumferential surface of the hub 7a. First and second inner raceways 20 and 21 which are side raceway surfaces are provided, respectively. The hub 7a is formed by combining a hub body 22 and an inner ring 23. At the outer end of the outer peripheral surface of the hub body 22, the mounting flange 11 a for supporting the wheel is also provided, the first inner raceway 20 is also provided at the intermediate portion, and the inner end track is also provided at the intermediate portion. The small-diameter step portions 24 each having a smaller diameter than the portion where the first inner ring raceway 20 is formed are provided. The inner ring 23 provided with the second inner ring raceway 21 having an arc-shaped cross section on the outer peripheral surface is externally fitted to the small-diameter stepped portion 24. Further, the inner end surface of the inner ring 23 is suppressed by a caulking portion 25 formed by plastically deforming the inner end portion of the hub body 22 radially outward, and the inner ring 23 is attached to the hub body 22. On the other hand, it is fixed. Further, seal rings 16c and 16d are provided between inner peripheral surfaces of both ends of the outer ring 19, an outer peripheral surface of an intermediate portion of the hub 7a, and an outer peripheral surface of an inner end of the inner ring 23, respectively. The balls 14 and 14 are set between the inner peripheral surface of the outer ring 19 and the outer peripheral surface of the hub 7a. It shields the girder space from the outside space.
上述した様な車輪支持用転がり軸受ユニット 2 (又は 2 a ) の場合、 玉 1 4、 1 4を設置した内部空間の両端開口部を塞いだシールリング 1 6 a、 1 6 b (又 は 1 6 c、 1 6 d ) の存在に基づき、 ハブ 7 (又は 7 a ) の回転に要するトルク (車輪支持用転がり軸受ユニットの回転抵抗） が大きくなる事が避けられない。 この結果、 上記車輪支持用転がり軸受ユニットを組み込んだ車両の、 加速性能、 燃費性能を中心とする走行性能が悪化する為、 近年に於ける省エネルギ化の流れ を受けて、 改良が望まれている。  In the case of the rolling bearing unit 2 (or 2a) for supporting wheels as described above, seal rings 16a, 16b (or 1a) are used to close the openings at both ends of the internal space where the balls 14, 14 are installed. Due to the existence of 6c, 16d), it is inevitable that the torque required for rotating the hub 7 (or 7a) (rotational resistance of the rolling bearing unit for wheel support) increases. As a result, the driving performance of the vehicle incorporating the above-mentioned rolling bearing unit for supporting the wheel, particularly the acceleration performance and the fuel consumption performance, is deteriorated. Therefore, in response to the recent trend of energy saving, improvement is desired. I have.
シールリング設置部分の抵抗を低減して転がり軸受の回転トルクを低減する構 造として従来から、 特開平 1 0— 2 5 2 7 6 2号公報に記載されたものの如きシ ールリップの締め代を工夫する構造の他、 軸受型式、 予圧量、 各部の形状、 接触 角や軌道面の曲率半径等の内部設計、 グリースの種類、 シールリングの形状ゃ材 料等を工夫する事が考えられている。 伹し、 これらの要素を互いに関連付けつつ 適正に規制して、 必要とするシール性能を確保し、 且つ、 上記回転トルクを低減 する設計は面倒であった。 この為、 より簡便に車輪支持用転がり軸受ユニットの 回転トルクを低減できる構造の実現が望まれている。  Conventionally, as a structure to reduce the rotational torque of the rolling bearing by reducing the resistance of the seal ring installation part, the tightening of the seal lip such as that described in Japanese Patent Application Laid-Open No. H10-2525272 has been devised. In addition to the structure, the design of the bearing type, the amount of preload, the shape of each part, the internal design such as the contact angle and the radius of curvature of the raceway surface, the type of grease, the shape of the seal ring, and the material are considered. However, it was troublesome to design these elements in a proper manner while associating them with each other to secure the required sealing performance and to reduce the rotational torque. Therefore, it is desired to realize a structure that can more easily reduce the rotational torque of the wheel supporting rolling bearing unit.
但し、 この回転トルクを低減する場合でも、 操縦安定性を確保すべく、 車輪の 支持剛性を確保する事、 転がり軸受ユニットの耐久性を確保すべく、 この転がり 軸受ュニットの内部空間への異物侵入防止を十分に図れる構造とする事が必要で ある。 即ち、 上記操縦安定性を確保する為には、 上記転がり軸受ユニットの剛性 を高くして上記支持剛性を確保する必要があるが、 単にこの剛性を高くすべく各 転動体に付与する予圧を高くすると、 これら各転動体の転がり抵抗が増大して、 上記回転トルクを低減できない。 又、 シールリングの摺動抵抗に関しても、 単に 低くする事のみを考えた場合には、 上記転がり軸受ユニットの内部空間への異物 侵入防止を十分に図れず、 上記耐久性を十分に確保できなくなる。  However, even if the rotational torque is reduced, foreign matter infiltrates into the internal space of the rolling bearing unit to secure the support rigidity of the wheel to secure the steering stability and to ensure the durability of the rolling bearing unit. It is necessary to have a structure that can sufficiently prevent such problems. In other words, in order to ensure the above steering stability, it is necessary to increase the rigidity of the rolling bearing unit to secure the supporting rigidity, but simply increase the preload applied to each rolling element in order to increase the rigidity. Then, the rolling resistance of each rolling element increases, and the rotational torque cannot be reduced. In addition, if the sliding resistance of the seal ring is merely considered to be low, it is not possible to sufficiently prevent foreign substances from entering the internal space of the rolling bearing unit, and it is impossible to sufficiently secure the durability described above. .
本発明の車輪支持用転がり軸受ュニットは、 この様な事情に鑑みて発明したも のである。 発明の開示 本発明の車輪支持用転がり軸受ュニットは、 前述した従来から知られている車 輪支持用転がり軸受ユニットと同様に、 静止側軌道輪と、 回転側軌道輪と、 複数 個の玉と、 1対のシールリングとを備える。 The rolling bearing unit for supporting wheels of the present invention has been invented in view of such circumstances. Disclosure of the invention The rolling bearing unit for supporting a wheel according to the present invention includes a stationary bearing ring, a rotating bearing ring, and a plurality of balls, as in the above-described conventionally known rolling bearing unit for supporting a wheel. And a seal ring.
このうちの静止側軌道輪は、 使用状態で懸架装置に支持固定される。  Of these, the stationary race is supported and fixed to the suspension device in use.
又、 上記回転側軌道輪は、 使用状態で車輪を支持固定する。  In addition, the rotating raceway rings support and fix the wheels in use.
又、 上記各玉は、 上記静止側軌道輪と回転側軌道輪との互いに対向する周面に 存在する、 それぞれが断面円弧形である静止側軌道面と回転側軌道面との間に設 けられている。  The balls are provided between the stationary raceway and the rotating raceway, each having an arc-shaped cross section, which are present on the peripheral surfaces of the stationary raceway and the rotating raceway facing each other. Have been killed.
更に、 上記 1対のシールリングは、 上記静止側軌道輪と上記回転側軌道輪との 互いに対向する周面同士の間で上記各玉を設置した空間の両端開口部を塞ぐ。 そして、 上記両シ一ルリングは、 それぞれが弾性材製である 2〜 3本のシ一ル リップを有する。  Further, the pair of seal rings close both end openings of the space in which the balls are installed between the opposing peripheral surfaces of the stationary raceway ring and the rotating raceway ring. Each of the two seal rings has two to three seal lips, each of which is made of an elastic material.
特に、 本発明の車輪支持用転がり軸受ユニットに於いては、 上記各玉に予圧を 付与する為のアキシアル荷重が、 0. 49〜 2. 94kN (50〜300kgf ) である。  In particular, in the rolling bearing unit for supporting a wheel of the present invention, the axial load for applying a preload to each of the balls is 0.49 to 2.94 kN (50 to 300 kgf).
又、 このアキシアル荷重が 1. 96 kN ( 200 kgf ) である場合の、 上記各 玉の転がり抵抗に基づく、 上記静止側軌道輪と上記回転側軌道輪とを 20 Omin-1 で相対回転させる為に要するトルク （転がり抵抗） が、 0. 12〜0. 23N • mである。 In addition, when the axial load is 1.96 kN (200 kgf), the stationary raceway and the rotating raceway are relatively rotated at 20 Omin- 1 based on the rolling resistance of each ball. The required torque (rolling resistance) is 0.12 to 0.23N • m.
又、 同じく上記アキシアル荷重が 1. 96 kNである場合の剛性係数が、 0. 09以上である。  Similarly, the rigidity coefficient is 0.09 or more when the axial load is 1.96 kN.
更に、 上記各シールリップと相手面との摩擦に基づく、 上記静止側軌道輪と上 記回転側軌道輪とを 20 Omin—1 で相対回転させる為に要するトルクが、 両シー ルリングの合計で 0. 06〜0. 4N 'mである。 Further, the torque required to rotate the stationary raceway and the rotating raceway relative to each other at 20 Omin- 1 based on the friction between each seal lip and the mating surface is 0 in total for both seal rings. 06 ~ 0.4N'm.
尚、 本明細書中に記載する上記剛性係数とは、 上記車輪支持用転がり軸受ュニ ットの剛性 R [kN · m/deg ] と、 この車輪支持用転がり軸受ュニットのラジ アル動定格荷重 C r [N] との比 （RZC r) である。 又、 この場合に於ける剛 性 Rは、 上記車輪支持用転がり軸受ュニットを構成する静止側軌道輪を固定した 状態で回転側軌道輪にモ一メント荷重を負荷した場合に於ける、 上記両軌道輪の 傾斜角度で表すもので、 例えば、 図 13に示す様にして測定する。 尚、 この図 1 3は、 前述の図 12に示した車輪支持用転がり軸受ユニット 2 aの剛性 Rを測定 する状態に就いて示している。 The stiffness coefficient described in this specification is the stiffness R [kN · m / deg] of the wheel-supporting rolling bearing unit, and the radial dynamic load rating of the wheel-supporting rolling bearing unit. It is the ratio (RZC r) to C r [N]. In addition, the rigidity R in this case is the above-mentioned rigidity when the momentary load is applied to the rotating raceway while the stationary raceway constituting the wheel supporting rolling bearing unit is fixed. Raceway It is expressed by the angle of inclination, and is measured, for example, as shown in FIG. FIG. 13 shows a state where the rigidity R of the wheel supporting rolling bearing unit 2a shown in FIG. 12 is measured.
測定作業時には、 静止側軌道輪である外輪 19を固定台 37の上面に固定する と共に、 回転側軌道輪であるハブ 7 aの取付フランジ 11 aに、 梃子板 38の基 端部 （図 13の左端部） を結合固定する。 そして、 この梃子板 38の上面で、 上 記八ブ 7 aの回転中心から、 タイヤの回転半径分の距離 Lだけ離れた部分に荷重 を加えて、 上記梃子板 38を介して上記ハブ 7 aに、 1. 5 kN ' mのモーメン ト荷重を加える。 このモーメント荷重に基づいて上記ハブ 7 aが、 上記外輪 19 に対し傾斜するので、 この傾斜角度を、 上記固定台 37の上面 39に対する上記 取付フランジ 1 1 aの取付面 40の傾斜角度 [deg ] として測定する。 そして、 上記モーメント荷重 （1. 5 kN， m) をこの傾斜角度で除する事により、 上記 剛性 R [kN - m/deg ] を求める。 更に、 この剛性 Rを上記車輪支持用転がり 軸受ユニット 2 aのラジアル動定格荷重 C r [N] で除する事により、 前記剛性 係数を求める。  During the measurement work, the outer ring 19, which is the stationary raceway, is fixed to the upper surface of the fixed base 37, and the base end of the lever plate 38 is attached to the mounting flange 11a of the hub 7a, which is the rotating raceway (Fig. 13). (The left end). Then, a load is applied to a portion of the upper surface of the lever plate 38, which is separated from the rotation center of the above-mentioned bracket 7a by a distance L corresponding to the rotation radius of the tire, and the hub 7a is provided via the lever plate 38. A moment load of 1.5 kN'm. Since the hub 7a is inclined with respect to the outer ring 19 based on the moment load, the inclination angle is determined by the inclination angle [deg] of the mounting surface 40 of the mounting flange 11a with respect to the upper surface 39 of the fixed base 37. Measured as Then, the rigidity R [kN-m / deg] is obtained by dividing the moment load (1.5 kN, m) by this inclination angle. Further, the rigidity coefficient is obtained by dividing the rigidity R by the radial dynamic load rating Cr [N] of the wheel supporting rolling bearing unit 2a.
上述の様に構成する本発明の車輪支持用転がり軸受ュニットの場合には、 必要 とする剛性及び耐久性を確保しつつ、 回転トルクを十分に低減できる。  In the case of the rolling bearing unit for supporting a wheel of the present invention configured as described above, the rotating torque can be sufficiently reduced while securing the required rigidity and durability.
即ち、 予圧を付与する為のアキシアル荷重を 0. 49 kN以上、 このアキシァ ル荷重が 1. 96 kNである場合の転がり抵抗を 0. 12N · m以上、 同じく岡 IJ 性係数を 0. 09以上とした事に伴い、 上記車輪支持用転がり軸受ユニットの剛 性を確保して、 操縦安定性を良好にできる。  That is, the axial load for applying the preload is 0.49 kN or more, the rolling resistance when this axial load is 1.96 kN is 0.12 Nm or more, and the Oka IJ coefficient is 0.09 or more. As a result, the rigidity of the wheel supporting rolling bearing unit is ensured, and steering stability can be improved.
これに対して、 上記予圧を付与する為のアキシアル荷重を 2. 94kN以下に、 上記転がり抵抗を 0. 23 N · m以下に、 1対のシールリングの回転抵抗 （トル ク） の合計を 0. 4N 'm以下に、 それぞれ抑えているので、 上記回転トルクの 低減を図れる。  On the other hand, the axial load for applying the preload is 2.94 kN or less, the rolling resistance is 0.23 N · m or less, and the total rotational resistance (torque) of a pair of seal rings is 0. . 4N'm or less, so the above-mentioned rotation torque can be reduced.
尚、 上記アキシアル荷重が 2. 94kNを越えると、 （例えば 0. 23Ν · πι 以下と言った様に） 上記転がり抵抗を低く抑える事ができなくなって、 上記回転 トルクを低減できなくなる。 これに対して、 上記アキシアル荷重が 0. 49 kN に満たない場合には、 上記車輪支持用転がり軸受ュニッ卜の剛性確保が難しくな つて、 操縦安定性が低下する。 If the axial load exceeds 2.94 kN, the rolling resistance cannot be suppressed to a low level (for example, 0.23 0 · πι or less), and the rotational torque cannot be reduced. On the other hand, if the axial load is less than 0.49 kN, it becomes difficult to secure the rigidity of the wheel supporting rolling unit unit. As a result, steering stability decreases.
又、 上記 1対のシールリングの回転抵抗の合計を 0. 4N 'm以下に抑えてい るので、 車輪支持用転がり軸受ュニット全体としての回転トルクを低減できる。 一方、 上記両シールリングの回転抵抗の合計を 0. 06Ν ·πι以上確保してい るので、 必要とするシール性能 （主として泥水の侵入防止の為の耐泥水性能） を 確保できる。  Further, since the total rotational resistance of the pair of seal rings is suppressed to 0.4 N'm or less, the rotational torque of the entire wheel supporting rolling unit can be reduced. On the other hand, since the total rotational resistance of the two seal rings is maintained at 0.06Ν · πι or more, the required sealing performance (mainly, muddy water resistance to prevent intrusion of muddy water) can be ensured.
即ち、 本発明者の行なった実験の結果、 各シ一ルリングに関して、 シールリツ プの数が 2本又は 3本である限り、 これら各シールリップの形状や材質を含め、 シールリングの構造に関係なく、 これら両シールリングの回転抵抗の合計の大小 により、 シール性能の適否を判定できる事が分かった。 勿論、 1対のシールリン グの回転抵抗の間の差が小さい事が、 回転抵抗の低いシールリングのシール性能 を確保する面から重要である。 この面から、 回転抵抗が低い方のシールリングに 関しても、 回転抵抗を 0. 03Ν · m以上確保する事が必要である。 回転抵抗の 低いシ一ルリングの回転抵抗を 0. 03 N · m以上確保し、 上記 1対のシールリ ングの回転抵抗の合計が 0. 06N · m以上であれば、 必要とするシール性能を 得られる事も分かった。  That is, as a result of an experiment conducted by the present inventors, as long as the number of seal lip is two or three, regardless of the shape and material of each seal lip, regardless of the structure of the seal ring, as long as the number of seal lip is two or three. However, it was found that the suitability of the sealing performance could be determined based on the sum of the rotational resistances of these two seal rings. Of course, a small difference between the rotational resistance of a pair of seal rings is important from the viewpoint of ensuring the sealing performance of a seal ring with low rotational resistance. From this aspect, it is necessary to secure a rotational resistance of at least 0.03 m even for the seal ring with the lower rotational resistance. The required sealing performance is obtained if the rotational resistance of the seal ring with low rotational resistance is at least 0.03 Nm and the total rotational resistance of the pair of seal rings is 0.06 Nm or more. I knew it would be possible.
これらにより、 上記 1対のシールリングの回転抵抗の合計が 0. 06〜0. 4 N · mである本発明の車輪支持用転がり軸受ュニッ卜の場合には、 必要とするシ ール性能を確保しつつ回転トルクを十分に低減できる事が分かる。  As a result, in the case of the rolling bearing unit for wheel support of the present invention in which the sum of the rotational resistances of the pair of seal rings is 0.06 to 0.4 Nm, the required sealing performance is improved. It can be seen that the rotational torque can be sufficiently reduced while securing.
以上の事から、 予圧を付与する為のアキシアル荷重が、 0. 49〜 2. 94k N、 このアキシアル荷重が 1. 96 kNである場合の転がり抵抗が 0. 12〜0. 23 N · m、 同じく剛性係数が 0. 09以上、 上記両シールリングの回転抵抗が 合計で 0. 06〜0. 4N · mである本発明の車輪支持用転がり軸受ユニットの 場合には、 剛性及び耐久性を確保しつつ、 回転トルクを十分に低減できる事が分 力る。 図面の簡単な説明  From the above, the axial load for applying the preload is 0.49 to 2.94 kN, and the rolling resistance when this axial load is 1.96 kN is 0.12 to 0.23 Nm, Similarly, in the case of the rolling bearing unit for supporting a wheel of the present invention in which the rigidity coefficient is 0.09 or more and the rotational resistance of both seal rings is 0.06 to 0.4 Nm in total, rigidity and durability are secured. While reducing the rotational torque. BRIEF DESCRIPTION OF THE FIGURES
図 1は、 本発明の対象となる構造の第 1例を示す断面図である。  FIG. 1 is a sectional view showing a first example of a structure to which the present invention is applied.
図 2は、 本発明の対象となる構造の第 2例を示す断面図である。 図 3は、 本発明の対象となる構造の第 3例を示す断面図である。 FIG. 2 is a cross-sectional view showing a second example of the structure to which the present invention is applied. FIG. 3 is a cross-sectional view showing a third example of the structure to which the present invention is applied.
図 4は、 本発明に適用し得るシールリングの具体的構造の第 1例を示す部分断 面図である。  FIG. 4 is a partial cross-sectional view showing a first example of a specific structure of a seal ring applicable to the present invention.
図 5は、 本発明に適用し得るシ一ルリングの具体的構造の第 2例を示す部分断 面図である。  FIG. 5 is a partial cross-sectional view showing a second example of the specific structure of the seal ring applicable to the present invention.
図 6は、 本発明に適用し得るシールリングの具体的構造の第 3例を示す部分断 面図である。  FIG. 6 is a partial cross-sectional view showing a third example of the specific structure of the seal ring applicable to the present invention.
図 7は、 本発明に適用し得るシールリングの具体的構造の第 4例を示す部分断 面図である。  FIG. 7 is a partial sectional view showing a fourth example of the specific structure of the seal ring applicable to the present invention.
図 8は、 本発明に適用し得るシールリングの具体的構造の第 5例を示す部分断 面図である。  FIG. 8 is a partial cross-sectional view showing a fifth example of the specific structure of the seal ring applicable to the present invention.
図 9は、 本発明に適用し得るシールリングの具体的構造の第 6例を示す部分断 面図である。  FIG. 9 is a partial cross-sectional view showing a sixth example of the specific structure of the seal ring applicable to the present invention.
図 1 0は、 本発明に適用し得るシールリングの具体的構造の第 7例を示す部分 断面図である。  FIG. 10 is a partial sectional view showing a seventh example of the specific structure of the seal ring applicable to the present invention.
図 1 1は、 従来から知られている車輪支持用転がり軸受ユニットの第 1例を、 懸架装置への組み付け状態で示す断面図である。  FIG. 11 is a cross-sectional view showing a first example of a conventionally known wheel-supporting rolling bearing unit when assembled to a suspension device.
図 1 2は、 従来から知られている車輪支持用転がり軸受ュニッ卜の第 2例を示 す断面図である。  FIG. 12 is a cross-sectional view showing a second example of a conventionally known rolling bearing unit for supporting a wheel.
図 1 3は、 車輪支持用転がり軸受ュニッ卜の剛性を測定する状態を示す断面図 である。 発明を実施するための最良の形態  FIG. 13 is a cross-sectional view showing a state in which the rigidity of the wheel supporting rolling bearing unit is measured. BEST MODE FOR CARRYING OUT THE INVENTION
先ず、 本発明の対象となる車輪支持用転がり軸受ュニットの構造の 3例に就い て説明する。 尚、 本発明は、 前述の図 1 1〜1 2に示した構造に関しても対象と なるが、 以下に述べる第 1〜 2例は、 本発明を、 駆動輪 （F R車の後輪、 F F車 の前輪、 4WD車の全輪） を回転自在に支持する為の車輪支持用転がり軸受ュニ ットに適用する場合に就いて示している。 本発明は、 駆動輪用の車輪支持用転が り軸受ユニットとして特に重要性が高い。 この理由は、 上記図 1 1〜1 2に示し た様な従動輪 （FR車の前輪、 FF車の後輪） 用の車輪支持用転がり軸受ュニッ トの場合、 外径側に位置する軌道輪 （図 11の場合は八ブ 7、 図 12の場合は外 輪 19) の一端開口をキャップ 17 (図 11) で塞ぐ事によりこの一端側のシ一 ルリング （16 a、 16 d) を省略し、 摺動抵抗を発生するシールリングを 1個 のみにできるのに対して、 駆動輪用の車輪支持用転がり軸受ユニットの場合には、 シールリングが 2個必要となる為である。 First, three examples of the structure of a rolling bearing unit for supporting a wheel, which is an object of the present invention, will be described. The present invention is also applicable to the structure shown in FIGS. 11 and 12 described above. However, the first and second examples described below apply the present invention to driving wheels (FR wheels, rear wheels, FF vehicles). It shows the case where the present invention is applied to a rolling bearing unit for supporting a wheel for rotatably supporting the front wheel of the vehicle and all wheels of a 4WD vehicle). The present invention is particularly important as a wheel supporting rolling bearing unit for driving wheels. The reason for this is shown in Figs. 11 and 12 above. In the case of a rolling bearing unit for supporting wheels such as driven wheels (front wheels of FR vehicles, rear wheels of FF vehicles), the raceway wheels located on the outer diameter side (Fig. In this case, the seal ring (16a, 16d) on one end side is omitted by closing one end opening of the outer ring 19) with the cap 17 (Fig. 11), and only one seal ring that generates sliding resistance On the other hand, in the case of a rolling bearing unit for supporting wheels for driving wheels, two seal rings are required.
先ず、 図 1に示した第 1例は、 前述の図 12に示した構造と同様に、 静止側軌 道輪である外輪 19の内径側に、 回転側軌道輪であるハブ 7 bを、 複数の玉 14、 14により、 回転自在に支持している。 上記ハブ 7 bを構成するハブ本体 22 a の中心部には、 等速ジョイントに付属のスプライン軸 （図示省略） を挿入する為 のスプライン孔 26を形成している。 又、 上記ハブ本体 22 aの内端部に形成し た小径段部 24に外嵌した内輪 23の内端面を、 このハブ本体 22 aの内端部を 径方向外方に塑性変形させて成るかしめ部 25により抑え付けて、 上記内輪 23 を上記ハブ本体 22 aに対し固定し、 上記ハブ 7 bを構成している。 そして、 上 記外輪 19の両端部内周面と、 上記ハブ本体 22 aの中間部外周面及び上記内輪 23の内端部外周面との間に、 それぞれシールリング 16 c、 16 dを設けて、 上記外輪 19の内周面と上記ハブ 7 bの外周面との間で上記各玉 14、 14を設 けた空間と、 外部空間とを遮断している。  First, in the first example shown in FIG. 1, similarly to the structure shown in FIG. 12, a plurality of hubs 7b, which are rotating-side races, are provided on the inner diameter side of the outer race 19, which is a stationary-side race. It is rotatably supported by balls 14 and 14. A spline hole 26 for inserting a spline shaft (not shown) attached to the constant velocity joint is formed in the center of the hub body 22a constituting the hub 7b. Further, the inner end surface of the inner ring 23 externally fitted to the small-diameter step portion 24 formed at the inner end of the hub body 22a is formed by plastically deforming the inner end of the hub body 22a radially outward. The inner ring 23 is fixed to the hub main body 22a by being held down by the caulking portion 25, thereby forming the hub 7b. Seal rings 16 c and 16 d are provided between the inner peripheral surfaces of both ends of the outer ring 19, the outer peripheral surface of the intermediate portion of the hub body 22 a, and the outer peripheral surface of the inner end of the inner ring 23, respectively. Between the inner peripheral surface of the outer ring 19 and the outer peripheral surface of the hub 7b, the space in which the balls 14, 14 are provided and the outer space are shut off.
この様な構造に本発明を適用する場合には、 上記ハブ本体 22 aの内端部に形 成する上記かしめ部 25を加工する際の荷重を適正に規制する事により、 上記各 玉 14、 14に予圧を付与する為のアキシアル荷重を 0. 49〜 2. 94kNと する。 そして、 このアキシアル荷重が 1. 96kNである場合の、 上記外輪 19 の内側で上記ハブ 7 bを 20 Omin— 1 で回転させる為に要するトルク （転がり抵 抗） を 0. 12〜0. 23N 'mとする。 又、 これと共に、 このアキシアル荷重 が 1. 96 kNである場合の剛性係数を、 0. 09以上とする。 更に、 上記両シ ールリング 16 c、 16 dの回転抵抗 （トルク） の合計を、 0. 06〜0. 4N •mの範囲に規制する。 そして、 上記各玉 14、 Ί 4を設置した空間内への、 泥 水等の異物侵入防止を、 上記両シールリング 16 c、 16 dにより行なう。 その 他の部分の構造は、 上記図 12に示した構造と同様である。 次に、 図 2に示した第 2例の場合には、 ハブ本体 2 2 bの内端部に設けた小径 段部 2 4に外嵌してこのハブ本体 2 2 bと共にハブ 7 cを構成する内輪 2 3の内 端面を、 このハブ本体 2 2 bの内端面よりも内方に突出させている。 車両への組 み付け状態で上記内輪 2 3の内端面には、 図示しない等速ジョイントの外端面が 突き当たり、 この内輪 2 3が上記小径段部 2 4から抜け落ちる事を防止する。 予 圧付与の為のアキシアル荷重は、 図示しないスプライン軸の外端部に螺着するナ ットを緊締するトルクにより調節する。 その他の構成は、 上述の図 1に示した第 1例の場合と同様である。 When the present invention is applied to such a structure, by appropriately regulating the load at the time of processing the caulked portion 25 formed at the inner end of the hub body 22a, the balls 14, 14 The axial load for applying a preload to 14 shall be 0.49 to 2.94 kN. When the axial load is 1.96kN, the torque (rolling resistance) required to rotate the hub 7b at 20 Omin- 1 inside the outer ring 19 is 0.12 to 0.23N '. m. In addition, the stiffness coefficient when this axial load is 1.96 kN is set to 0.09 or more. Furthermore, the total rotational resistance (torque) of the two seal rings 16c and 16d is restricted to a range of 0.06 to 0.4Nm. Then, the intrusion of foreign substances such as muddy water into the space where the balls 14 and 4 are installed is performed by the seal rings 16c and 16d. The structure of the other parts is the same as the structure shown in FIG. Next, in the case of the second example shown in FIG. 2, the hub 7c is formed together with the hub main body 2 2b by externally fitting the small-diameter step portion 24 provided at the inner end of the hub main body 22b. The inner end surface of the inner ring 23 protrudes more inward than the inner end surface of the hub body 22 b. The outer end surface of the constant velocity joint (not shown) abuts on the inner end surface of the inner ring 23 in a state where the inner ring 23 is mounted on the vehicle, thereby preventing the inner ring 23 from falling off the small diameter step portion 24. The axial load for applying the preload is adjusted by the tightening torque of the nut screwed to the outer end of the spline shaft (not shown). Other configurations are the same as those in the first example shown in FIG. 1 described above.
次に、 図 3に示した第 3例の場合には、 本発明を、 前述の図 1 1に示す様な、 従動輪を回転自在に支持する為の転がり軸受ュニットに適用する場合に就いて示 している。 前述した図 1 1に示す構造が、 支持軸 4の外端部に螺着したナット 6 により 1対の内輪 5、 5を固定しているのに対して、 本例は、 支持軸 4 aの中間 部に第一の内輪軌道 2 0を直接形成すると共に、 この支持軸 4 aの外端部を径方 向外方に塑性変形させて成るかしめ部 2 5により内輪 5の外端面を抑え付けて、 この内輪 5を上記支持軸 4 aに固定している。 予圧付与の為のアキシアル荷重は、 上記かしめ部 2 5を加工する際の荷重により調節する。 その他の部分の構造は、 前述の第 1例並びに上記図 1 1に示した構造と同様である。  Next, in the case of the third example shown in FIG. 3, the present invention is applied to a case where the present invention is applied to a rolling bearing unit for rotatably supporting a driven wheel as shown in FIG. 11 described above. Is shown. While the structure shown in FIG. 11 described above fixes a pair of inner rings 5 and 5 with a nut 6 screwed to the outer end of the support shaft 4, the present example The first inner ring raceway 20 is formed directly in the middle part, and the outer end surface of the inner ring 5 is held down by a caulking part 25 formed by plastically deforming the outer end of the support shaft 4a radially outward. The inner ring 5 is fixed to the support shaft 4a. The axial load for applying the preload is adjusted by the load at the time of processing the caulked portion 25. The structure of the other parts is the same as that of the first example described above and the structure shown in FIG.
次に、 本発明に適用し得るシールリングの具体的構造の 7例に就いて、 図 4〜 1 0により説明する。 このうち、 図 4〜8に示した 5例は、 前記図 1〜3に示し た車輪支持用転がり軸受ュニットの第 1〜 3例及び先に説明した図 1 1〜 1 2の 構造で、 内側のシールリング 1 6 b、 1 6 dとして利用可能な構造を示している。 尚、 以下の説明は、 図 1〜2の構造に適用する場合を例に説明する。  Next, seven examples of the specific structure of the seal ring applicable to the present invention will be described with reference to FIGS. Of these, the five examples shown in FIGS. 4 to 8 are the first to third examples of the wheel-supporting rolling unit shown in FIGS. 1 to 3 and the structures of FIGS. This shows a structure that can be used as the seal rings 16b and 16d. The following description will be made by taking as an example a case where the present invention is applied to the structures shown in FIGS.
先ず、 図 4に示した第 1例は、 外輪 1 9 (図 1〜2 ) の内端部に内嵌固定する 外径側シールリング 2 7と、 内輪 2 3 (図 1〜2 ) の内端部に外嵌固定する内径 側シールリング 2 8とを組み合わせた組み合わせシ一ルリングであり、 内径側に 2本、 外径側に 1本の、 合計 3本のシールリップを備える。  First, the first example shown in FIG. 4 includes an outer-diameter-side seal ring 27 that is internally fitted and fixed to the inner end of an outer ring 19 (FIGS. 1 and 2), and an inner ring 23 (FIGS. 1 and 2). This is a combination seal ring combining an inner diameter side seal ring 28 that is externally fitted and fixed to the end, and has a total of three seal lips, two on the inner diameter side and one on the outer diameter side.
次に、 図 5に示した第 2例は、 外輪 1 9 (図 1〜2 ) の内端部に内嵌固定する シールリング 2 9と、 内輪 2 3 (図 1〜2 ) の内端部に外嵌固定するスリンガ 3 0とを組み合わせた組み合わせシ一ルリングであり、 上記シールリング 2 9に 3 本のシ一ルリップを備える。 Next, a second example shown in FIG. 5 is a seal ring 29 that is fitted and fixed to the inner end of the outer ring 19 (FIGS. 1 and 2), and an inner end of the inner ring 23 (FIGS. 1 and 2). This is a combination seal ring in which a slinger 30 that is externally fitted and fixed to the seal ring is used. With book seal lip.
次に、 図 6に示した第 3例は、 外輪 19 (図 1〜2) の内端部に内嵌固定する シールリング 29 aを構成する 2本のシールリップ 31 a、 31 bのうちの内側 のシールリップ 3 l aを、 ガータスプリング 32により、 内輪 23 (図 1〜2) の内端部外周面に摺接させる構造としている。  Next, in a third example shown in FIG. 6, the two seal lips 31a and 31b of the two seal lips 31a and 31b constituting the seal ring 29a which is fitted and fixed to the inner end of the outer ring 19 (FIGS. 1 and 2) The inner seal lip 3 la is slidably contacted with the outer peripheral surface of the inner end of the inner ring 23 (FIGS. 1-2) by the garter spring 32.
次に、 図 7に示した第 4例は、 外輪 19 (図 1〜2) の内端部内周面に係止す るシールリング 33 aと、 内輪 23 (図 1〜2) の内端部外周面に係止するシー ルリング 33 bとを組み合わせた組み合わせシールリングである。 本例の場合、 上記外輪 19側に係止するシールリング 33 aに 2本、 内輪 23側に係止するシ ールリング 33 bに 1本の、 合計 3本のシールリップを備える。  Next, a fourth example shown in FIG. 7 shows a seal ring 33a which is locked to the inner peripheral surface of the inner end of the outer ring 19 (FIGS. 1 and 2), and an inner end of the inner ring 23 (FIGS. 1 and 2). This is a combination seal ring combining the seal ring 33b which is locked to the outer peripheral surface. In the case of the present example, a total of three seal lips are provided, two on the seal ring 33a locked on the outer ring 19 side and one on the seal ring 33b locked on the inner ring 23 side.
次に、 図 8は、 外輪 19 (図 1〜2) の内端部に内嵌するシールリング 34に 設けた 2本のシールリップの先端縁を、 内輪 23 (図 1〜2) の内端部外周面に 摺接させるものである。  Next, FIG. 8 shows the front edges of the two seal lips provided on the seal ring 34 fitted inside the inner end of the outer ring 19 (FIGS. 1 and 2), and the inner end of the inner ring 23 (FIGS. 1 and 2). This is to make sliding contact with the outer peripheral surface.
次に、 図 9〜10に示した 2例は、 外輪 19 (図 1〜2) の外端部内周面とハ ブ本体 22 a (図 1) 、 22 b (図 2) の中間部外周面との間に設けるシールり ングとして利用可能な構造を示している。  Next, the two examples shown in Figs. 9 and 10 show the inner peripheral surface of the outer end of the outer ring 19 (Figs. 1-2) and the outer peripheral surface of the intermediate part of the hub bodies 22a (Fig. 1) and 22b (Fig. The figure shows a structure that can be used as a sealing provided between them.
先ず、 図 9に示した第 1例のシールリング 35は、 上記外輪 19の外端部に内 嵌固定自在な芯金に 3本のシールリップを設けたもので、 これら各シールリップ の先端緣を、 取付フランジ 11 a (図 1〜2) の内側面、 或はこの内側面と上記 ハブ本体 22 a、 22 bの外周面とを連続させる曲面部に摺接自在としている。 次に、 図 10に示した第 2例の場合には、 シールリング 35 aに設けた 3本の シールリップのうちの中間のシールリップ 36を、 ガー夕スプリング 32 aによ り、 ハブ本体 22 a (図 1) 、 22b (図 2) の中間部外周面に押し付ける様に している。  First, the seal ring 35 of the first example shown in FIG. 9 is provided with three seal lips on a core metal that can be fitted and fixed at the outer end of the outer ring 19. Can be slidably contacted with the inner surface of the mounting flange 11a (FIGS. 1 and 2) or a curved surface portion connecting the inner surface to the outer peripheral surfaces of the hub bodies 22a and 22b. Next, in the case of the second example shown in FIG. 10, the middle seal lip 36 of the three seal lips provided on the seal ring 35a is connected to the hub body 22 by the girder spring 32a. a (Fig. 1) and 22b (Fig. 2).
上述の様な、 図 4〜10に示した中から選択した 1対のシールリングは、 前述 の図 1〜3に示した車輪支持用転がり軸受ュニッ卜を構成する外輪 19 (図 1〜 2) 、 ハブ 7 (図 3) の両端部内周面とハブ本体 22 a (図 1) 、 22 b (図 2) 、 支持軸 4 a (図 3) の中間部外周面及び内輪 23の内端部外周面 （図 1〜 2) 、 内輪 5の外端部外周面 （図 3) との間に組み付けて、 玉 14、 14を設置 した空間の両端開口部を塞ぐ。 そして、 何れのシールリング同士を組み合わせた 場合でも、 両シールリングの回転抵抗の合計を、 0. 06〜0. 4N 'mの範囲 に規制する。 又、 回転抵抗の低い方のシールリングの回転抵抗を 0. 03N ' m 以上確保する。 実施例 As described above, a pair of seal rings selected from those shown in FIGS. 4 to 10 are used for the outer ring 19 (FIGS. 1 and 2) which constitutes the wheel supporting rolling bearing unit shown in FIGS. , The inner peripheral surface of both ends of the hub 7 (Fig. 3), the outer peripheral surface of the intermediate portion of the hub body 22a (Fig. 1), 22b (Fig. 2), the support shaft 4a (Fig. 3), and the outer peripheral surface of the inner end of the inner ring 23. Balls 14 and 14 are installed by assembling between the surface (Figs. Close the openings at both ends of the space. Then, regardless of which seal ring is combined, the total rotational resistance of both seal rings is restricted to the range of 0.06 to 0.4N'm. Also, ensure that the rotational resistance of the seal ring with the lower rotational resistance is at least 0.03 N 'm. Example
次に、 本発明の効果を確認する為に行なった実験の結果に就いて説明する。 実 験では、 図 4〜10に示した 7種類のシールリングのうちから選択した 1対のシ ールリングを、 前記図 1又は図 3に示した車輪支持用転がり軸受ュニットに組み 付け、 これら両シールリングの回転抵抗 （シールトルク） の合計値とシール性能 との関係を求めた。 シールトルクの調節は、 シールリップの締め代 （弹性変形 量） の調整、 弾性材の変更、 相手面との接触状態の調整により行なった。 そして、 上記 7種類のシールリング同士の組み合わせを 12種類用意し、 それぞれに就い て、 シールトルクの合計値が 0. 01〜0. 1 ON · mまでのものを 6種類ずつ 製作した。 そして、 各シールリングを、 図 1又は図 3に示した車輪支持用転がり 軸受ユニットに組み込んで、 泥水浸入試験に供した。 車輪支持用転がり軸受ュニ ットの潤滑は、 粘度が 10 X 10—6〜 14X 10—6m2 /s (10〜14c S t) のグリースを封入する事により行ない、 20°Cの環境下で、 ハブ 7 b (又は 7) を 20 Omin"1 で回転させた。 Next, the results of experiments performed to confirm the effects of the present invention will be described. In the experiment, a pair of seal rings selected from the seven types of seal rings shown in Figs. 4 to 10 were assembled to the wheel-supporting rolling bearing unit shown in Fig. 1 or 3 above. The relationship between the total value of the rotational resistance (seal torque) of the ring and the sealing performance was determined. The adjustment of the sealing torque was performed by adjusting the sealing margin (the amount of elastic deformation) of the seal lip, changing the elastic material, and adjusting the state of contact with the mating surface. Twelve combinations of the above seven types of seal rings were prepared, and six types with a total seal torque value of 0.01 to 0.1 ON · m for each were manufactured. Then, each seal ring was assembled into a wheel supporting rolling bearing unit shown in FIG. 1 or FIG. 3 and subjected to a muddy water intrusion test. Lubrication of the wheel supporting rolling bearing Interview two Tsu DOO is performed by a viscosity encapsulating grease 10 X 10- 6 ~ 14X 10- 6 m 2 / s (10~14c S t), 20 ° C environment Below, the hub 7b (or 7) was rotated at 20 Omin " 1 .
この様な条件で行なった実験の結果を次の表 1に示す。  Table 1 shows the results of the experiment performed under such conditions.
[表 1] [table 1]
シ-觸 シールリングの組み合わせ  Combination of seal ring
(Ni) ④+⑩ ④ +⑨ ④ +⑥ ④ +⑧ ⑤+⑩ ⑤ +⑨ ⑤ +⑥ ⑤ +® ⑦ ⑦ +⑨ ⑦ +© ⑦ +⑧ (Ni) ④ + ⑩ ④ + ⑨ ④ + ⑥ ④ + ⑧ ⑤ + ⑩ ⑤ + ⑨ ⑤ + ⑥ ⑤ + ® ⑦ ⑦ + ⑨ ⑦ + © ⑦ + ⑧
0. 01 X X X X X X X X X X X X0. 01 X X X X X X X X X X X X
0. 03 O O X X Δ Δ X X X X X X0.03 O O X X Δ Δ X X X X X X
0. 05 O o Δ Δ O O Δ Δ Δ Δ X X0.05 O o Δ Δ O O Δ Δ Δ Δ X X
0. 06 O o O O O O O O O O 〇 O0.06 O o O O O O O O O O 〇 O
0. 08 O o O o o O O O O O O O0.08 O o O o o O O O O O O O O
0. 1 0 O o O o o O O 〇 O O O O 尚、 この表 1中、 丸で囲まれた数字は、 当該シールリングを記載した図面番号 を表している。 例えば、 ④は図 4に示したシールリングを、 ⑨は図 9に示したシ ールリングを、 それぞれ表している。 又、 ④ +⑨とは、 図 4に示したシールリン グと図 9に示したシールリングとを組み合わせた事を表している。 又、 「X J 印 はグリースを封入した内部空間に多量の泥水が浸入した事を、 「△」 印は少量の 泥水が浸入した事を、 「〇」 印は泥水の浸入が観測されなかった事を、 それぞれ 表している。 この様な実験の結果から、 シールトルクが 0 . 0 6 N ' m以上であ れば、 何れの構造のシールリングを組み合わせた場合でも、 泥水の浸入を阻止で きる事が分かる。 0.10 O o O oo OO 〇 OOOO In Table 1, the circled numbers represent the drawing numbers describing the seal rings. For example, ④ indicates the seal ring shown in FIG. 4, and ⑨ indicates the seal ring shown in FIG. 9, respectively. Also, ④ + 組 み 合 わ せ indicates that the seal ring shown in FIG. 4 and the seal ring shown in FIG. 9 are combined. In addition, `` XJ mark '' means that a large amount of muddy water has infiltrated the internal space filled with grease, `` △ '' means that a small amount of muddy water has entered, and `` 〇 '' means that no infiltration of muddy water has been observed. , Respectively. From the results of such an experiment, it can be seen that if the seal torque is 0.06 N'm or more, the infiltration of muddy water can be prevented in any combination of seal rings of any structure.
次に、 シールトルク （回転抵抗） 、 予圧付与の為のアキシアル荷重、 転がり抵 抗、 剛性係数が、 操縦安定性、 転がり軸受ユニット全体の回転トルク、 耐久性に 及ぼす影響を知る為に、 図 1に示した車輪支持用転がり軸受ユニットに、 図 4に 示したシールリングと図 9に示したシールリングとを組み込んで行なつた、 第二 〜第五の実験に就いて、 表 2〜 5を参照しつつ説明する。  Next, to understand the effects of seal torque (rotational resistance), axial load for applying preload, rolling resistance, and stiffness coefficient on steering stability, rotational torque of the entire rolling bearing unit, and durability, Fig. 1 Tables 2 to 5 show the results of the second to fifth experiments in which the seal ring shown in Fig. 4 and the seal ring shown in Fig. 9 were incorporated into the rolling bearing unit for wheel support shown in Fig. 4. It will be described with reference to FIG.
尚、 以下に示す表 2〜 5中、 「X」 印は何らかの面で実用上問題が生じた事を、 「△」 印は何らかの面で若干の問題が生じた事を、 「〇」 印は何れの面からも問 題が生じなかった事を、 それぞれ表している。 尚、 第二〜第五の実験は、 同じ条 件で 3回ずつ行なった。  In Tables 2 to 5 below, the symbol “X” indicates that some problem occurred in some aspects, the symbol “△” indicates that some problem occurred in some aspects, and the symbol “〇” indicates It indicates that no problem occurred from any aspect. The second to fifth experiments were performed three times under the same conditions.
先ず、 表 2は、 上記シールトルクが、 転がり軸受ユニット全体の回転トルク、 耐久性に及ぼす影響を知る為に行なった、 第二の実験の結果に就いて示している。 尚、 この実験は、 回転速度 2 0 O miir1で行なった。 First, Table 2 shows the results of a second experiment conducted to find out the effect of the sealing torque on the rotation torque and durability of the entire rolling bearing unit. This experiment was performed at a rotation speed of 20 Omiir 1 .
[表 2] [Table 2]
Figure imgf000015_0001
この表 2に示した第二の実験の結果、 上記シールトルクが 0. 06〜0. 40 N *mの範囲にあれば、 転がり軸受ユニット全体の回転トルク、 耐久性の何れの 面からも満足できる性能を得られる事が分かった。 これに対して、 上記シール卜 ルクが 0. 01N ' m、 0. 03N 'm及び 0. 05 N · mの場合には、 玉 14、 14を設置した内部空間への異物進入を十分に防止できず、 耐久性確保の面で問 題を生じた。 これに対して、 上記シールトルクが 0. 42N 'm、 0. 45N · m及び 0. 5 ON · mの場合には、 転がり軸受ュニット全体の回転トルクを十分 に低く抑える事ができなかった。
Figure imgf000015_0001
As a result of the second experiment shown in Table 2, if the above-mentioned sealing torque is in the range of 0.6 to 0.40 N * m, it is satisfactory from both aspects of the running torque and durability of the entire rolling bearing unit. I found that I could get the performance I could. On the other hand, when the seal torque is 0.01 N'm, 0.03 N'm and 0.05 Nm, the foreign matter is sufficiently prevented from entering the internal space where the balls 14 and 14 are installed. As a result, there was a problem in securing durability. On the other hand, when the sealing torque was 0.42 N'm, 0.45 N · m, and 0.5 ON · m, the rotation torque of the entire rolling bearing unit could not be suppressed sufficiently.
次に、 表 3は、 前記アキシアル荷重 （予圧） が、 転がり軸受ユニットの剛性及 び全体の回転トルクに及ぼす影響を知る為に行なった、 第三の実験の結果に就い て示している。 Next, Table 3 shows the results of a third experiment performed to determine the effect of the axial load (preload) on the stiffness of the rolling bearing unit and the overall rotational torque.
[表 3] [Table 3]
Figure imgf000016_0001
この表 3に示した第三の実験の結果、 上記アキシアル荷重が 0. 49〜2. 9 4kNであれば、 操縦安定性、 転がり軸受ユニット全体の回転トルクの何れの面 からも満足できる性能を得られる事が分かった。 これに対して、 上記アキシアル 荷重が 0. 294 kN及び 0. 392 kNの場合には、 上記転がり軸受ュニット の剛性が低く、 十分な操縦安定性を確保できなかった。 これに対して、 上記アキ シアル荷重が 3. 43k N及び 3. 92 k Nの場合には、 転がり抵抗が高くなつ て、 転がり軸受ュニット全体の回転トルクを十分に低く抑える事ができなかった。 次に、 表 4は、 前記転がり抵抗が、 転がり軸受ユニットの剛性及び全体の回転 トルクに及ぼす影響を知る為に行なった、 第四の実験の結果に就いて示している。 尚、 この実験は、 アキシアル荷重 （予圧） を 1. 96 kN ( 200 kgf ) 付与す ると共に、 回転速度 20 Omin- で行なった。
Figure imgf000016_0001
As a result of the third experiment shown in Table 3, if the above-mentioned axial load is 0.49 to 2.94 kN, satisfactory performance can be obtained from both aspects of steering stability and rotational torque of the entire rolling bearing unit. I found that I could get it. On the other hand, when the axial load was 0.294 kN and 0.392 kN, the rigidity of the rolling bearing unit was low, and sufficient steering stability could not be secured. On the other hand, when the axial load was 3.43 kN and 3.92 kN, the rolling resistance was high, and the rotational torque of the entire rolling bearing unit could not be suppressed sufficiently. Next, Table 4 shows the results of a fourth experiment performed to determine the effect of the rolling resistance on the rigidity of the rolling bearing unit and the overall rotational torque. This experiment was performed with an axial load (preload) of 1.96 kN (200 kgf) and a rotation speed of 20 Omin-.
[表 4] [Table 4]
Figure imgf000017_0001
この表 4に示した第四の実験の結果、 上記転がり抵抗が 0. 12〜0. 23Ν •mであれば、 操縦安定性、 転がり軸受ユニット全体の回転トルクの何れの面か らも満足できる性能を得られる事が分かった。 これに対して、 上記転がり抵抗が 0. 1 N · m及び 0. 11 N · mの場合には、 上記転がり軸受ュニットの剛性が 低く、 十分な操縦安定性を確保できなかった。 これに対して、 上記転がり抵抗が 0. 24N ·m及び0. 25N · mの場合には、 転がり軸受ユニット全体の回転 トルクを十分に低く抑える事ができなかつた。
Figure imgf000017_0001
As a result of the fourth experiment shown in Table 4, if the above-mentioned rolling resistance is 0.12 to 0.23 mm, the steering stability and the rotational torque of the entire rolling bearing unit can be satisfied. It turns out that performance can be obtained. On the other hand, when the rolling resistance was 0.1 N · m or 0.11 N · m, the rigidity of the rolling bearing unit was low, and sufficient steering stability could not be secured. On the other hand, when the rolling resistance was 0.24 N · m or 0.25 N · m, the rotation torque of the entire rolling bearing unit could not be sufficiently suppressed.
更に、 表 5は、 前記剛性係数が、 転がり軸受ユニットの剛性に及ぼす影響を知 る為に行なった、 第五の実験の結果に就いて示している。 尚、 この実験は、 アキ シアル荷重を 1. 96 kN (20 Okgf ) 付与した状態で行なった。  Further, Table 5 shows the results of a fifth experiment conducted to determine the effect of the rigidity coefficient on the rigidity of the rolling bearing unit. This experiment was performed with an axial load of 1.96 kN (20 Okgf) applied.
[表 5] [Table 5]
Figure imgf000017_0002
この表 5に示した第五の実験の結果、 上記剛性係数が 0. 09以上であれば、 操縦安定性に関して満足できる性能を得られる事が分かった。 これに対して、 上 記剛性係数が 0 . 0 7、 0 . 0 8の場合には、 上記転がり軸受ユニットの剛性が 低く、 十分な操縦安定性を確保できなかった。
Figure imgf000017_0002
As a result of the fifth experiment shown in Table 5, it was found that if the stiffness coefficient was 0.09 or more, satisfactory performance in terms of steering stability could be obtained. In contrast, When the rigidity coefficient was 0.07 or 0.08, the rigidity of the rolling bearing unit was low, and sufficient steering stability could not be secured.
更に、 次の表 6は、 前記シールトルクと前記転がり抵抗とが、 転がり軸受ュニ ット全体としての回転トルクに及ぼす影響に就いて知る為に行なった実験の結果 を示している。 尚、 この実験は、 アキシアル荷重を 1 . 9 6 k N ( 2 0 0 kgf ) 付与すると共に、 回転速度 2 0 O min- で行なった。  Further, Table 6 below shows the results of an experiment conducted to find out the effect of the sealing torque and the rolling resistance on the rotation torque of the rolling bearing unit as a whole. In this experiment, an axial load of 1.96 kN (200 kgf) was applied, and the rotation speed was 20 O min-.
[表 6 ] [Table 6]
Figure imgf000018_0001
尚、 この表 6中、 「X」 印は全体としての回転トルクが大きかった事を、 「△」 印はやや大きかった事を、 「〇」 印は小さかった事を、 それぞれ表してい る。 この様な表 6から明らかな通り、 1対のシールリングのシールトルクの合計 を 0 . 4 N · m以下、 転がり抵抗を 0 . 2 3 N · m以下に抑えた本発明は、 全体 としての回転トルクを 0 . 6 3 N · m以下と、 低く抑える事ができる。 産業上の利用の可能性
Figure imgf000018_0001
In Table 6, “X” indicates that the rotational torque as a whole was large, “△” indicates that it was slightly large, and “〇” indicates that it was small. As is clear from Table 6, the present invention in which the total sealing torque of a pair of seal rings is suppressed to 0.4 Nm or less and the rolling resistance is suppressed to 0.23 Nm or less, as a whole, The rotational torque can be kept low, at 0.63 Nm or less. Industrial applicability
本発明の車輪支持用転がり軸受ュニットは、 以上に述べた通り構成され作用す るので、 操縦安定性及び耐久性を確保しつつ、 車輪と共に回転するハブの回転ト ルクを低減して、 加速性能、 燃費性能を中心とする車両の走行性能の向上に寄与 できる。  Since the rolling bearing unit for supporting a wheel according to the present invention is configured and operates as described above, the steering torque and the rotating torque of the hub that rotates with the wheel are reduced while maintaining the steering stability and durability, thereby improving the acceleration performance. However, it can contribute to the improvement of the running performance of vehicles mainly on fuel efficiency.

Claims

請求の範囲 The scope of the claims
1. 使用状態で懸架装置に支持固定される静止側軌道輪と、 使用状態で車輪を支 持固定する回転側軌道輪と、 これら静止側軌道輪と回転側軌道輪との互いに対向 する周面に存在する、 それぞれが断面円弧形である静止側軌道面と回転側軌道面 との間に設けられた複数個の玉と、 上記静止側軌道輪と上記回転側軌道輪との互 いに対向する周面同士の間で上記各玉を設置した空間の両端開口部を塞ぐ 1対の シールリングとを備え、 これら両シールリングは、 それぞれが弾性材製である 2 〜 3本のシ一ルリップを有するものである車輪支持用転がり軸受ュニッ卜に於い て、 上記各玉に予圧を付与する為のアキシアル荷重が 0. 49〜2. 94kNで あり、 このアキシアル荷重が 1. 96 kNである場合の、 上記各玉の転がり抵抗 に基づく、 上記静止側軌道輪と上記回転側軌道輪とを 20 Omin—1 で相対回転さ せる為に要するトルクが 0. 12〜0. 23N*mであり、 同じく上記アキシァ ル荷重が 1. 96k Nである場合の剛性係数が 0. 09以上であり、 上記各シ一 ルリップと相手面との摩擦に基づく、 上記静止側軌道輪と上記回転側軌道輪とを1. A stationary raceway that is supported and fixed to the suspension device in use, a rotating raceway that supports and fixes the wheels in use, and opposing peripheral surfaces of the stationary raceway and the rotating raceway A plurality of balls provided between the stationary-side raceway surface and the rotating-side raceway surface each having an arc-shaped cross section; A pair of seal rings for closing the openings at both ends of the space where the above-mentioned balls are installed between the opposing peripheral surfaces, and these two seal rings are made of an elastic material; In a rolling bearing unit for wheel support that has a rlip, the axial load for applying a preload to each ball is 0.49 to 2.94 kN, and this axial load is 1.96 kN. In some cases, based on the rolling resistance of each ball, the stationary raceway The torque required to rotate relative to the said rotary bearing ring at 20 Omin- 1 is 0.12 to 0. A 23N * m, the stiffness coefficient of the case also the Akishia Le load is 1. 96k N 0.09 or more, and based on the friction between each of the above-mentioned sealing lip and the mating surface,
20 Omir1 で相対回転させる為に要するトルクが、 両シールリングの合計で 0. 06〜0. 4N · mである事を特徴とする車輪支持用転がり軸受ュニット。 20 Rolling bearing unit for wheel support, characterized in that the torque required for relative rotation in Omir 1 is 0.06 to 0.4 Nm in total for both seal rings.
PCT/JP2003/002370 2002-03-01 2003-02-28 Rolling bearing unit for supporting wheel WO2003074890A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2003211541A AU2003211541A1 (en) 2002-03-01 2003-02-28 Rolling bearing unit for supporting wheel

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2002-55660 2002-03-01
JP2002055660A JP2005299685A (en) 2002-03-01 2002-03-01 Rolling bearing unit for wheel support

Publications (1)

Publication Number Publication Date
WO2003074890A1 true WO2003074890A1 (en) 2003-09-12

Family

ID=27784616

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2003/002370 WO2003074890A1 (en) 2002-03-01 2003-02-28 Rolling bearing unit for supporting wheel

Country Status (3)

Country Link
JP (1) JP2005299685A (en)
AU (1) AU2003211541A1 (en)
WO (1) WO2003074890A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1548307A1 (en) * 2002-09-06 2005-06-29 Nsk Ltd., Rolling bearing unit for supporting wheel
US9751361B2 (en) 2012-04-13 2017-09-05 Ntn Corporation Seal device for a wheel bearing

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5354186B2 (en) * 2008-07-09 2013-11-27 Ｎｔｎ株式会社 Reduction gear
WO2010004880A1 (en) * 2008-07-09 2010-01-14 Ntn株式会社 Reduction gear and variable valve timing device using same
JP5376288B2 (en) * 2008-08-25 2013-12-25 Ｎｔｎ株式会社 Variable valve timing device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07113418A (en) * 1993-10-18 1995-05-02 Toyota Motor Corp Vehicle bearing device and manufacture thereof
JPH1123598A (en) * 1997-06-27 1999-01-29 Nippon Seiko Kk Bearing provided with rotating speed detector
JP2001121904A (en) * 1999-10-27 2001-05-08 Ntn Corp Wheel bearing device

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07113418A (en) * 1993-10-18 1995-05-02 Toyota Motor Corp Vehicle bearing device and manufacture thereof
JPH1123598A (en) * 1997-06-27 1999-01-29 Nippon Seiko Kk Bearing provided with rotating speed detector
JP2001121904A (en) * 1999-10-27 2001-05-08 Ntn Corp Wheel bearing device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1548307A1 (en) * 2002-09-06 2005-06-29 Nsk Ltd., Rolling bearing unit for supporting wheel
EP1548307A4 (en) * 2002-09-06 2007-07-04 Nsk Ltd Rolling bearing unit for supporting wheel
US7338212B2 (en) 2002-09-06 2008-03-04 Nsk, Ltd. Wheel supporting rolling bearing unit
US9751361B2 (en) 2012-04-13 2017-09-05 Ntn Corporation Seal device for a wheel bearing

Also Published As

Publication number Publication date
AU2003211541A1 (en) 2003-09-16
JP2005299685A (en) 2005-10-27

Similar Documents

Publication Publication Date Title
KR100642588B1 (en) Rolling bearing unit for supporting wheel
US20050018939A1 (en) Wheel support bearing assembly
JP2014126106A (en) Rolling bearing unit for supporting wheel
JP2003222145A (en) Wheel support rolling bearing unit with seal ring
EP1548306A1 (en) Rolling bearing unit for supporting wheel
WO2003071146A1 (en) Rolling bearing unit for supporting wheel
WO2003074890A1 (en) Rolling bearing unit for supporting wheel
JP3794008B2 (en) Wheel bearing
JP4085736B2 (en) Rolling bearing device
JP5708403B2 (en) Sealing device for bearing
WO2003071148A1 (en) Rolling bearing unit for wheel support
US9133876B2 (en) Wheel bearing device
WO2003071147A1 (en) Rolling bearing unit for supporting wheel
JP5790109B2 (en) Rolling bearing device
JP4221831B2 (en) Rolling bearing unit for wheels
CN218294198U (en) Bearing device for wheel
JP2023159713A (en) hub unit bearing
JP2024019837A (en) hub unit bearing
JP2024013116A (en) hub unit bearing
JP2024018646A (en) hub unit bearing
JP2024006580A (en) hub unit bearing
JP2013019427A (en) Bearing unit

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SC SD SE SG SK SL TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PT SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP