Patent Application
20240207879
This application is based on and claims priority to Italian Patent Application No. 102022000014737 filed on Jul. 13, 2022, under 35 U.S.C. § 119, the disclosure of which is incorporated herein by reference in its entirety.
The present disclosure relates to wheel hub unit for vehicles.
Exposed surfaces of a wheel hub are often coated with a protective coating or film to protect them from contaminants, such as water and debris.
Known wheel hub units are often also equipped with markings, such as a QR code, data matrix, etc., and magnetized parts, such as magnetic encoders of ABS devices. During application of the protective layer or film to the wheel hub unit, these markings and magnetized parts may become damaged or obscured if protective coating is provided to them, affecting the readability and operation of these components.
The disclosure will now be described with reference to the attached drawings, which illustrate non-limiting exemplary embodiments in which:
A wheel hub unit may include an outer annular element, such as a radially outer ring, with a raceway provided an a radially inner surface, an inner annular element, such as a radially inner ring, with a raceway provided on a radially outer surface, and a plurality of rolling bodies interposed between the radially outer and inner elements and engaged with the raceways. One of the annular elements rotates about a central axis of rotation of the wheel hub unit and may include a spindle provided on an “outboard” side of the wheel hub unit. The wheel hub unit may include a mounting flange for mounting on a wheel of a vehicle and a collar that protrudes axially from the mounting flange to guide the vehicle wheel onto the mounting flange.
In use, both the collar and the mounting flange are exposed to numerous contaminants, such as water, mud, dust, and sand. During assembly and disassembly, for example to change tires, the collar and the mounting flange may further be subject to chafing. These parts of the wheel hub unit can therefore easily be subject to corrosion, resulting in rust and other effects that deteriorate these components and reduce their operating life.
A protective coating (layer or film), for example, made of photo-polymerizable synthetic material, may be applied to exposed surfaces of the wheel hub unit to protect them from these contaminants and chafing. However, the protective coating can be damaging to other elements present on the wheel hub unit. Certain markings, such as QR codes and data matrices, on the surface of the wheel hub unit may be obfuscated by this protective coating, which can render these markings unreadable. Further, magnetic components of the wheel hub unit may be damaged by this protective coating as well, such as an encoder for an ABS system.
It is therefore necessary to design a solution for wheel hub units described above which protects these markings and magnetized parts from damage caused by the protective coating or film.
With reference to the figures, some embodiments of a wheel hub unit 1 may include an outer annular element 2, such as a radially outer ring 2, a radially inner annular element 4, such as a radially inner ring 4, and a plurality of rolling bodies 6 interposed between radially outer ring 2 and radially inner ring 4. Outer ring 2 may include a plurality of first rolling raceways 3 formed on a radially inner surface of outer ring 2, and inner ring 4 may include a plurality of second rolling raceways 5 formed on a radially outer surface of inner ring 4 and positioned radially opposite first rolling raceways 3. In some embodiments, each rolling body of plurality of rolling bodies 6 engages a respective first rolling raceway 3 and a respective second rolling raceway 5. In some embodiments, plurality of rolling bodies 6 may form two rows of rolling bodies. In some embodiments, rolling bodies 6 may be balls, rollers, needle rollers, or the like.
Throughout this disclosure and in the claims, description of an “outboard” side of wheel hub unit 1 refers to the side of wheel hub unit 1 intended to face toward the outside of a vehicle when assembled on the vehicle. Similarly, description of an “inboard” side of wheel hub unit 1 refers to the side of wheel hub unit 1 that faces the inside of a vehicle when wheel hub unit 1 is assembled on the vehicle.
In some embodiments, inner ring 4 may rotate about an axis of rotation A of wheel hub unit 1 and outer ring 2 may be stationary. In such embodiments, inner ring 4 may include a spindle 7 formed on an outboard side of wheel hub unit 1. Spindle 7 may include a mounting flange 8 for mounting wheel hub unit 1 onto a vehicle wheel (not illustrated for simplicity). In some embodiments, mounting flange 8 may include an axially facing front surface 11 that extends radially from axis A and is interrupted by a plurality of through holes 10 arranged annularly about mounting flange 8.
It will be appreciated by a person of ordinary skill in the art that, in some embodiments, inner ring 4 may be stationary and outer ring 2 may rotate about an axis of rotation A of wheel hub unit 1. In such embodiments, outer ring 2 may include a spindle 7 formed on the outboard side of wheel hub unit 1.
In some embodiments, the rotating element, e.g., rotating inner ring 4, may be provided with a collar, e.g., a cylindrical guide sleeve portion 9, which extends axially from front surface 11 of mounting flange 8, at a side of wheel hub unit 1 radially opposite spindle 7. Collar 9 may include a radially outer peripheral side surface 12e and a radially inner peripheral side surface 12i. In some embodiments, collar 9 may be coaxial with spindle 7. In some embodiments, collar 9 may be perpendicular to front surface 11 and may also be cantilevered.
In some embodiments, collar 9 may receive a drum/brake disc and the wheel of a vehicle when wheel hub unit 1 is assembled with the vehicle. In some embodiments, the wheel may be fixed to mounting flange 8 using plurality of through holes 10.
In some embodiments, outer ring 2 and inner ring 4 may be coaxial with spindle 7 and collar 9, and all these elements may be coaxial with axis of symmetry A of wheel hub unit 1.
In some embodiments, a protective coating layer 13 may be applied to front surface 11 of mounting flange 8. A material of protective coating layer 13 may be, for example, a UV paint, e.g., a synthetic material polymerizable by UV rays, or a zinc flake paint, e.g., paint containing zinc and aluminum dispersed in an organic matrix. In some embodiments, protective coating layer 13 may also be applied to a radially outer surface 2e of radially outer ring 2 and/or to side surfaces 12e and 12i of collar 9.
In some embodiments, front surface 11 of mounting flange 8 may include a central annular portion 11a that houses plurality of through holes 10, whereby through holes 10 alternate annularly with solid portions of central annular portion 11a. In some embodiments, one or more markings 22, e.g., a QR code, a data matrix, a bar code, etc., may be made on one or more solid portions of central annular portion 11a between adjacent through holes 10.
In some embodiments, an external, disc-shaped shield 20 may be used to shield annular portion 11a of front surface 11 to protect one or more markings 22 during application of protective coating layer 13. Shield 20 may have a geometry that is identical or substantially identical to a geometry of central annular portion 11a in order to protect markings 22 while allowing for other portions of front surface 11 to be coated with protective coating layer 13. By covering markings 22 with shield 20 during application of protective coating layer 13, malfunctions caused by protective coating layer 13 covering some or all of markings 22 and making makings 22 intelligible, which can result in malfunctions to markings 22, are prevented.
In some embodiment, magnetic components of wheel hub unit 1, such as an encoder 30, may be protected by a spindle 31, illustrated in
In some embodiments, disc-shaped shield 20 may not be in contact with wheel hub unit 1, but may rather be positioned a predetermined axial distance “d” from central annular portion 11a by means of a handling arm 21. Handling arm 21 may include an end 21a attachable to disc-shaped shield 20. End 21a and disc-shaped shield 20 may form a tool that can be replaced according to needs of a particular wheel hub unit, such as a wheel hub unit of different size and shape than wheel hub unit 1 described herein.
It will be appreciated by a person of ordinary skill in the art that, in some embodiments, handling arm 21 and disc-shaped shield 20 may be considered a separate unit to be used in production of a wheel hub unit, i.e., they can be positioned in any painting station where it is necessary to mask a surface of a wheel hub unit. In such embodiments, end 21a of handling arm 21 may be integrally formed with disc-shaped shield 20 and interchangeable as an entire unit.
Predetermined axial distance “d” may take into account a position and a relative spatial orientation of spray nozzle 14 with respect to front surface 11 of mounting flange 8. In some embodiments, axial distance “d” and an angle of inclination a of spray nozzle 14, taken with respect to axis of symmetry A of wheel hub unit 1, may be such that an axis X of spray nozzle 14 creates a point of impact tangent to an area to be coated with protective coating spray 13, e.g., front surface 11. In some embodiments, axis X of spray nozzle 14 may be a central axis that passes through a center of spray nozzle 14 along which protective coating layer 13 is provided to wheel hub unit 1.
In some embodiments, disc-shaped shield 20 may be made of a material with sufficient structural resistance to resist displacement caused by pressure applied by spray nozzle 14 during application of protective coating layer 13, as well as be substantially flat with respect to front surface 11 of mounting flange 8. In some embodiments, disc-shaped shield 20 may be made of a metallic material, e.g., steel or aluminum, or a plastic material, such as polyamide polymers (PA6) or polytetrafluoroethylene (PFTE). A disc-shaped shield 20 made of a metallic material has further advantages of possessing resistance to solvents and other materials used as cleaning liquids, and to abrasion caused from removal of excess paint with a brush.
As discussed, the sizing, shape, and geometry of disc-shaped shield 20 are a function of the sizing, shape, and geometry of central portion 11a where one or more markings 22 are located.
In some embodiments, a disc-shaped shield 20 made of a metallic material may have a minimum thickness of 0.5 mm, and a disc-shaped shield 20 made of a non-metallic material may have a minimum thickness of 1.0 mm. These dimensions ensure an adequate rigidity of disc-shaped shield 20 such that disc-shaped shield 20 does not bend during application of protective coating spray 13 and allow protective coating layer 13 to contact central portion 11a and one or more markings 22. To limit the weight of disc-shaped shield 20, a maximum thickness thereof may not exceed 5 mm, whether disc-shaped shield 20 is made of a metallic material or a non-metallic material.
Finally, to further ensure coverage of central portion 11a during application of protective coating layer 13, disc-shaped shield 20 may have a radial length equal to a radial length of an area to be protected by painting, e.g., central annular portion 11a, ±5%. This relationship ensures that plurality of markings 20 are protected from protective coating layer 13, which can include potential splashes during application of protective coating layer 13.
With reference to
In some embodiments, wheel hub unit 1 may rest on spindle 31 by means of an edge 2a of radially outer ring 2 and may be centered on platform 16 by means of a radially internal surface 4a of radially inner ring 4. A rotation speed of spindle 31 may be adjusted to manage application of protective coating layer 13.
Optionally, at step 402, one or more mechanical operations may be performed on wheel hub unit 1. In some embodiments, step 402 may include treating front surface 11 of flange 8 to improve absorption of protective coating layer 13 applied at step 403. In some embodiments, one or more mechanical operations may include known mechanical operations, such as chip removal, surface finishing and lapping, etc. In some embodiments, performing one or more mechanical operations on wheel hub unit 1 may result in wheel hub unit 1 achieving an oscillation tolerance in the range of 10 μm to 15 μm to ensure that wheel hub unit 1 can withstand oscillations caused by rotating of wheel hub assembly about platform 16 during step 403 of method 400.
At step 403, a protective coating layer, e.g., protective coating layer 13, may be applied to wheel hub unit 1. In some embodiments, protective coating layer 13 may be applied to front surface 11 of mounting flange 8. Disc-shaped shield 20 may be positioned an axial distance “d” above central annular portion 11a during application of protective coating layer 13, thereby preventing application of protective coating layer 13 to central annular portion 11a of front surface 11. In some embodiments, disc-shaped shield 20 may be attached to or integral with an end 21a of mounting arm 21, which holds disc-shaped shield 20 in place during step 403.
In some embodiments, step 403 of applying a protective coating layer may include spraying protective coating layer 13 on front surface 11 using spray nozzle 14. Step 403 may further include rotating wheel hub unit 1 on platform 16 about axis of symmetry A in order to obtain a uniform layer of protective coating layer. In some embodiments, a position of spray nozzle 14 may be adjusted to spray a different surface of wheel hub unit 1 to which protective coating spray 13 is to be applied, e.g., outer surface 2e of outer ring 2, surface 12e and 12i of collar 9.
In this way, markings 20 and magnetic elements 30 that provide signals to sensor, e.g., ABS sensors, are shielded from protective coating layer 13 by disc-shaped shield 20 and spindle 31, respectively. Furthermore, configurations and methods according to exemplary embodiments of this disclosure eliminate burrs formed around disc-shaped shield 20.
In some embodiments, method 400 may further include an optional step 404 of cleaning disc-shaped shield 20. Cleaning disc-shaped shield 20 may include performing a washing treatment on disc-shaped shield 20 in a washing tank 18.
In addition to the exemplary embodiments of the disclosure described herein, it is to be understood that numerous other variants exist. It is also to be understood that such embodiments are exemplary only and limit neither the scope of the disclosure, its applications, nor its possible configurations. On the contrary, although the description herein allows a person of ordinary skill in the art to carry out the present disclosure, it may be understood that many variants of the components described are possible, without thereby departing from the scope of the disclosure, as defined in the attached claims, which are interpreted literally and/or according to their legal equivalents.
It should be noted that the use of particular terminology when describing certain features or embodiments of the disclosure should not be taken to imply that the terminology is being re-defined herein to be restricted to include any specific characteristics of the features or embodiments of the disclosure with which that terminology is associated. Terms and phrases used in this disclosure, and variations thereof, especially in the appended claims, unless otherwise expressly stated, should be construed as open-ended as opposed to limiting. As examples of the foregoing, the term “including” should be read to mean “including, without limitation,” “including but not limited to,” or the like; the term “comprising” as used herein is synonymous with “including,” “containing,” or “characterized by,” and is inclusive or open-ended and does not exclude additional, unrecited elements or method steps; the term “having” should be interpreted as “having at least”; the term “such as” should be interpreted as “such as, without limitation”; the term “includes” should be interpreted as “includes but is not limited to”; the term “example” is used to provide exemplary instances of the item in discussion, not an exhaustive or limiting list thereof, and should be interpreted as “example, but without limitation”; adjectives such as “known,” “normal,” “standard,” and terms of similar meaning should not be construed as limiting the item described to a given time period or to an item available as of a given time, but instead should be read to encompass known, normal, or standard technologies that may be available or known now or at any time in the future; and use of terms like “preferably,” “preferred,” “desired,” or “desirable,” and words of similar meaning should not be understood as implying that certain features are critical, essential, or even important to the structure or function of the present disclosure, but instead as merely intended to highlight alternative or additional features that may or may not be utilized in a particular embodiment.
Likewise, a group of items linked with the conjunction “and” should not be read as requiring that each and every one of those items be present in the grouping, but rather should be read as “and/or” unless expressly stated otherwise. Similarly, a group of items linked with the conjunction “or” should not be read as requiring mutual exclusivity among that group, but rather should be read as “and/or” unless expressly stated otherwise. The terms “about” or “approximate” and the like are synonymous and are used to indicate that the value modified by the term has an understood range associated with it, where the range may be ±20%, ±15%, ±10%, ±5%, or ±1%. The term “substantially” is used to indicate that a result (e.g., measurement value) is close to a targeted value, where close may mean, for example, the result is within 80% of the value, within 90% of the value, within 95% of the value, or within 99% of the value. Also, as used herein “defined” or “determined” may include “predefined” or “predetermined” and/or otherwise determined values, conditions, thresholds, measurements, and the like.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102022000014737 | Jul 2022 | IT | national |
