JP4178306B2 - Hub unit for vehicles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle hub unit.
[0002]
[Prior art]
In general, the vehicle hub unit is roughly classified into a type used on the driving wheel side of a vehicle such as an automobile and a type used on the driven wheel side.
[0003]
Among these, as shown in FIG. 5, a drive wheel type vehicle hub unit 50 supports a hub wheel 51 to which a wheel or a disc rotor of a disc brake device is attached, a constant velocity joint 52, and these rotatably around an axis. A double row rolling bearing 53 is provided. The outer ring of the constant velocity joint 52, that is, the shaft portion 54A integrally formed on the outer end side (vehicle outboard side) in the axial center direction of the main body hook portion (hereinafter simply referred to as the “hook portion”) 54 is a hub wheel. The double-row rolling bearing 53 is spline-fitted into the central hole 51, and is arranged so as to pass over the outer peripheral surfaces of the hub wheel 51 and the flange portion 54 of the constant velocity joint 52.
[0004]
Further, the outer peripheral surface of the hub wheel 51 or the constant velocity joint 52 on the outer end side in the axial center direction of the outer ring 55 of the double row rolling bearing 53 and the inner end side in the axial direction of the outer ring 55 (vehicle inboard side). A contact-type seal 56 is attached to prevent contact of foreign matter such as muddy water into the double row rolling bearing 53 in contact with the outer peripheral surface of the shape portion 54.
[0005]
[Problems to be solved by the invention]
In the above-described conventional vehicle hub unit 50, as the seal mechanism, the contact type seal 56 is merely in contact with the outer peripheral surface of the hub wheel 51 or the outer peripheral surface of the bowl-shaped portion 54 of the constant velocity joint 52. Foreign matter such as muddy water is likely to enter the double row rolling bearing 53, so that the lubricity of the lubricant applied to the inside of the double row rolling bearing 53 deteriorates early, and the life of the double row rolling bearing 53 is shortened. It was.
[0006]
In addition, since the double row rolling bearing 53 and the constant velocity joint 52 are attached to the hub wheel 51 in close proximity, heat generated from the double row rolling bearing 53 and the constant velocity joint 52 is conducted to each other. In use, the temperature tends to increase synergistically, and the inside of the bearing 53 is almost sealed by the contact seal 56, so that the lubricant applied to the inside of the double row rolling bearing 53 is quickly deteriorated by heat. As a result, the lubricity tends to decline. For this reason, the life of members such as the double row rolling bearing 53 and the constant velocity joint 52 has been shortened.
[0007]
Then, this invention aims at provision of the hub unit for vehicles which can solve the said subject.
[0008]
[Means for Solving the Problems]
The problem-solving means in the present invention is provided with a hub wheel for mounting a wheel and a rolling bearing for rotatably supporting the hub wheel around its axis on the outer periphery of the hub wheel. An inner ring member on the vehicle inboard side is fitted to the hub wheel by a caulking portion formed at an end of the hub wheel on the vehicle inboard side, and a constant velocity joint that supports the hub wheel in a tiltable manner is connected to a large-diameter outer ring. A rotating shaft with a small diameter provided at one end thereof, the rotating shaft is integrally inserted and supported by the hub wheel, and the end surface of the outer ring of the constant velocity joint and the end surface of the caulking portion of the hub wheel are spaced in the axial direction. And a seal device for preventing foreign matter from entering the rolling bearing and the gap between the outer ring of the rolling bearing and the outer ring of the constant velocity joint. Is provided et is, the sealing device is a non-contact seal having sealing portion base attached to the outer ring outer circumferential surface of the constant velocity joint, and is extended from the base to cover the vehicle inboard side end portion of the outer ring of the rolling bearing A member, a core part fixed to the inner peripheral surface of the outer ring of the rolling bearing on the vehicle inboard side, a contact piece fixed to the core part, a contact piece that contacts the inner ring member, and a non-contact seal member A contact-type sealing member having a contact piece .
[0010]
Furthermore, an uneven portion is formed on the outer peripheral surface of the seal portion of the non-contact type seal member to guide the air flow to the outer ring side of the rolling bearing when the outer ring of the constant velocity joint rotates.
[0011]
In the above configuration, when the constant velocity joint rotates around the axis, the member on the constant velocity joint side ( non-contact type seal member ) of the sealing device also rotates around the axis . Since this sealing device is provided between the outer ring of the rolling bearing and the outer ring of the constant velocity joint, foreign matter such as muddy water is inside the rolling bearing, or between the end surface of the outer ring of the constant velocity joint and the caulking portion of the hub wheel . Prevents entry into the gap between the end faces.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, the vehicle hub unit 1 according to the first embodiment of the present invention is used on the drive wheel side of an automobile, and a hub wheel 2 to which a wheel (not shown) is attached; A rotating member R is composed of a constant velocity joint 5 in which a small-diameter shaft portion 4 (rotating shaft) is formed on the vehicle outboard side in an insertion hole 3 formed in the hub wheel 2. A double-row rolling bearing 6 that is rotatably supported around is provided.
[0013]
A male spline that is spline-fitted to the female spline of the hub wheel 2 is formed on the outer peripheral surface of the shaft portion 4, and the shaft portion 4 is tightened by a nut 4 a that enters the recess 2 a of the hub wheel 2, Movement in the C direction is prevented.
[0014]
The hub wheel 2 is formed with a flange 7 projecting radially outward in the middle of the outer peripheral surface thereof, and a brake disc rotor 11 is fixed to the flange 7 via a hub bolt 7a.
[0015]
Reference numeral 13 in the figure denotes a brake pad for braking the rotation of the brake disc rotor 11.
[0016]
The constant velocity joint 5 is a well-known member called a Rzeppa type (Burfield type), and has a bowl-shaped section 15 having a large-diameter section with the shaft section 4 formed integrally on one side, on the engine side. An inner ring 17 through which a drive shaft 22 to be connected is inserted and fixed, a ball 10 for tilting and guiding the hub wheel 2 with respect to the drive shaft 22 and a retainer 20 thereof are provided.
[0017]
One end of the drive shaft 22 is spline-fitted to the inner ring 17, and the drive shaft 22 is secured to the inner ring 17 by a retaining ring (not shown). The other end of the drive shaft 22 is attached to a vehicle differential device via another constant velocity joint (not shown).
[0018]
In the hub wheel 2, an inner ring member 25 described later having a single track on the vehicle inboard side is fitted by a caulking portion 2 b at the end of the hub wheel 2. A predetermined gap 31 is provided between the caulking portion 2 b and the end portion of the bowl-shaped portion 15 of the constant velocity joint 5.
[0019]
The double row rolling bearing 6 includes a single outer ring 16 having two rows of raceway grooves, and an axial outer end surface 16 a of the outer ring 16 is disposed at a position close to the flange 7 of the hub wheel 2. Further, the double row rolling bearing 6 includes a plurality of balls 9a and 9b as rolling elements arranged in two rows, and two crown-shaped cages 23, and one of the two inner rings that is originally required is a hub. The other uses the raceway surface of the wheel 2 and the other uses the outer circumferential surface of the inner ring member 2b as the raceway surface. In the middle of the outer peripheral surface of the outer ring 16, a radially outward flange 8 is formed on which a knuckle 12 fixed to the vehicle body is fastened with a bolt 12a.
[0020]
An annular contact-type seal member 32 for sealing a gap between the vehicle outboard side of the outer ring 16 of the double row rolling bearing 6 and the flange 7 of the hub wheel 2 is provided. It is comprised from the metal core 33 fixed to an internal peripheral surface, and the contact piece 34 which contacts the outer peripheral surface of the hub wheel 2. As shown in FIG.
[0021]
A sealing device 35 for sealing the gap 31 is provided. The sealing device 35 includes a contact-type seal member 36 and a non-contact-type seal member 37, and the contact-type seal member 36 includes the outer ring 16. A core portion 38 fixed to the inner peripheral surface of the inner ring member 25, and a contact piece 40 fixed to the core portion 38 and contacting an outer peripheral surface of the inner ring member 25 and a base portion 39 of a non-contact type seal member 37 described later. Yes. The outer diameter of the core portion 38 of the contact seal member 36 is smaller than the diameter of the outer ring 16.
[0022]
The non-contact type seal member 37 includes the base 39 fitted to the stepped portion of the bowl-shaped portion 15 of the constant velocity joint 5 and the end of the outer ring 16 of the double row rolling bearing 6 from the outer peripheral end of the base 39. The seal 41 has an annular seal portion 41 that is curved and extended so as to cover the outer periphery of the outer ring 16 of the double row rolling bearing 6 with a slight gap at the tip. Yes. Further, the seal portion 41 distributes the air flow over the entire outer circumferential surface of the constant velocity joint 5 during rotation of the flange portion 15 of the double-row rolling bearing 6 from the vehicle inboard side to the vehicle outboard side. An uneven portion 42 inclined with respect to the axis C is formed in the direction of guiding to the center, and the unevenness is arranged along the direction of the axis C.
[0023]
In the vehicle hub unit 1 configured as described above, the rotational power of the drive shaft 22 is transmitted to the constant velocity joint 5 and the hub wheel 2, that is, the rotating member R, and is also transmitted to the wheels to rotate.
[0024]
Here, the function of the sealing device 35 will be described. The non-contact type seal member 37 of the sealing device 35 has an annular seal portion 41 extending so as to cover the end portion of the outer ring 16 of the double row rolling bearing 6, and the tip portion of the double row rolling bearing 6. Since the outer ring 16 is arranged with a slight gap in the circumferential direction on the outer peripheral surface, foreign matter such as muddy water is difficult to enter the gap 31. Further, when the bowl-shaped portion 15 of the constant velocity joint 5 rotates around the axis C, the non-contact type seal member 37 rotates around the axis C accordingly. The non-contact type seal member 37 is further rotated around the axis C to further improve the sealing performance (labyrinth action).
[0025]
In addition, since the uneven portion 42 is formed on the peripheral surface of the seal portion 41, the uneven portion 42 moves (rotates) as the non-contact seal member 37 rotates around the axis C. Thus, an air flow, particularly a flow from the vehicle inboard side to the vehicle outboard side, is generated in the outer peripheral portion of the seal portion 41, and the movement of the uneven portion 42 and this air flow are combined, so that the foreign matter is in the vicinity of the seal portion 41. Therefore, foreign matter can be prevented from entering the gap 31.
[0026]
Further, since the contact-type seal member 36 having the contact piece 40 that contacts the base 39 of the non-contact-type seal member 37 is provided, the contact-type seal member 36 also ensures that foreign matter enters the gap 31. Can be prevented.
[0027]
By the way, since the outer diameter of the contact-type seal member 36 is smaller than the diameter of the outer ring 16, the vehicle hub unit 1 can be easily assembled to the knuckle 12.
[0028]
As described above, according to the first embodiment of the present invention, the non-contact type seal member 37 of the seal device 35 is extended to cover the end of the outer ring 16 of the double row rolling bearing 6 from the vehicle inboard side. The portion 41 is formed, and the tip portion thereof is arranged with a slight gap on the outer peripheral surface of the outer ring 16 of the double row rolling bearing 6, and the uneven portion 42 is formed on the peripheral surface of the seal portion 41. It is possible to reliably prevent foreign matter such as muddy water from entering the gap 31, and by preventing foreign matter from entering the gap 31, corrosion of the fitting portion between the shaft portion 4 and the hub wheel 2 can be prevented. The life of the double row rolling bearing 6 can be extended.
[0029]
In addition, since the air flow is generated on the outer periphery of the seal portion 41 due to the movement of the concavo-convex portion 42, the temperature rise of the non-contact type seal member 37 is suppressed, and therefore the contact piece 40 of the contact type seal member 36 is not Even if the contact-type seal member 37 is in contact with the base portion 39, the temperature rise of the contact-type seal member 36 can be suppressed and this life can be extended, and deterioration of the lubricant in the double row rolling bearing 6 can be prevented. be able to.
[0030]
Next, a second embodiment of the present invention will be described based on FIG. The vehicle hub unit 1 according to the second embodiment of the present invention is a rotation for detecting the rotational speed of a wheel at a position facing the uneven portion 42 of the seal portion 41 on the vehicle inboard side panel surface of the knuckle 12. A sensor 45 is attached. The rotation sensor 45 detects the moving speed of the concavo-convex portion 42 as a signal and outputs this signal to a control device (not shown). The control device calculates the rotation speed of the wheel based on this signal. Other configurations and operational effects are the same as those in the first embodiment, and are omitted.
[0031]
In the above embodiment, the uneven portion 42 of the seal portion 41 is arranged along the axis C, but is not limited to this, and is inclined with respect to the axis C as shown in FIG. In this case, an air flow can be generated more reliably on the vehicle outboard side by the rotation of the non-contact type sealing member 37, and foreign matters can be eliminated.
[0032]
【The invention's effect】
As is apparent from the above description, the present invention provides a seal for preventing foreign matter from entering the rolling bearing and the gap between the end surface of the outer ring of the constant velocity joint and the end surface of the caulking portion of the hub wheel. than providing the device, it is possible to prevent the constant-velocity joint side of the member of the sealing device together with the rotation of the constant velocity joint (non-contact type seal member) penetrates foreign matter into the gap improved sealability by rotating Therefore, the life of a member such as a rolling bearing can be extended.
[Brief description of the drawings]
FIG. 1 is an enlarged cross-sectional view of a vehicle hub unit according to a first embodiment of the present invention.
FIG. 2 is a partially enlarged perspective view of a non-contact type sealing member.
FIG. 3 is a schematic cross-sectional view of a vehicle hub unit showing a second embodiment of the invention.
FIG. 4 is a partially enlarged perspective view of a non-contact type sealing member showing another embodiment.
FIG. 5 is a schematic sectional view of a conventional vehicle hub unit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Vehicle hub unit 2 Hub wheel 2b Caulking part 5 Constant velocity joint 6 Double row rolling bearing 12 Knuckle 15 Outer ring 22 Drive shaft 31 Clearance 35 Sealing device 36 Contact-type seal member 37 Non-contact-type seal member 41 Seal part 42 Concavity and convexity

Claims (2)

A hub wheel for mounting the wheel and a rolling bearing for rotatably supporting the hub wheel around its axis on the outer periphery of the hub wheel are provided, and at least the inner ring member on the vehicle inboard side of the rolling bearing is A constant velocity joint, which is fitted to the hub wheel by a caulking portion formed at the end of the hub wheel on the vehicle inboard side and supports the hub wheel in a tiltable manner, has a large diameter outer ring and a small diameter provided at one end thereof. The rotating shaft is integrally inserted and supported by the hub wheel, and the end surface of the outer ring of the constant velocity joint and the end surface of the caulking portion of the hub wheel are arranged with a gap in the axial direction, and is a rolling bearing. the foreign matter sealing device for preventing the intrusion provided we are inside and to the gap rolling bearing between the outer ring and the outer ring of the constant velocity joint,
The seal device includes a base attached to the outer ring outer peripheral surface of the constant velocity joint, and a non-contact seal member having a seal part extending from the base and covering a vehicle inboard side end of the outer ring of the rolling bearing;
A core part fixed to the inner peripheral surface of the outer ring of the rolling bearing on the vehicle inboard side, as a contact piece fixed to the core part, a contact piece that contacts the inner ring member, and a contact piece that contacts the non-contact seal member A contact-type sealing member having
A vehicle hub unit comprising: The outer peripheral surface of the seal portion of the non-contact type sealing member, according to claim 1 Symbol, characterized in that the uneven portion for during rotation of the outer race to guide the flow of air to the outer side of the rolling bearing is formed Hub unit for vehicles listed.

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