NL2021850B1 - Wheel assembly with static hubcap. - Google Patents

Abstract

The invention relates to a wheel assembly with a static wheel cap. For dead axles, or using driven axles driven by an in-wheel motor such as an Axial Field Permanent Magnet 5 motor, or Radial Field Permanent Magnet motor, or another in-wheel motortype showing a stator (102) at the rotation axis (112), a hubcap (150) can fixedly be mounted on the stator. This results in a truly static hubcap, as opposed to the ‘floating’ hubcap described in US patent publication US4,929,030 to Seung M Park. To protect displays, sensors and bearings from dirt and water, an at least locally 10 transparent wheel cover (460) can be mounted on the rotor.

Description

Wheel assembly with static hubcap.

Technical field ofthe invention.

[0001] The invention relates to a wheel assembly for a vehicle, the wheel assembly comprising a hubcap, a stator and a rotor, the rotor supported by the stator using one or more bearings, the rotor capable of rotating around a rotation axis, the rotor supporting or comprising a rim for mounting a tire thereupon, the stator extending along the rotation axis, the wheel assembly at a first side of the wheel assembly connected to a suspension system of the vehicle and the wheel assembly having a second side opposite to the first side that is not connected to the suspension system, the hubcap located at the second side.

Background ofthe invention.

[0002] A hubcap, wheel cover or wheel trim is typically a decorative disk on the wheel of a vehicle that covers at least a central portion ofthe wheel, called the hub. A hubcap often shows a logo of the car manufacturer. In most cases the hubcap rotates with the wheel.

[0003] Wheel assemblies for vehicles with a non-rotating axle and a load-bearing rotor surrounding the axle, so-called dead axles or lazy axles, are known for non-powered wheel assemblies. However, when the wheel is powered, the power is transferred from the motor to the so-called drive axle in the middle ofthe wheel assembly and the load bearing is performed (via bearings) by a stator that surrounds the drive axle. The drive axle thus rotates. This makes it impossible, or at least unappealing, to make a (powered) wheel assembly with a hubcap located at the second side whose orientation is stationary with respect to the suspension located on the first side.

[0004] Non-rotating hubcaps, retaining the same orientation even when a vehicle is in motion, are known from e.g. US patent publication US4,929,030 to Seung M Park, further referred to as Park. Here the hubcap is made rotatable with respect to the wheel using bearings, and by adding an eccentric weight to the hubcap the hubcap shows a preferential orientation. During acceleration/deceleration ofthe vehicle the hubcap will deviate from the preferential orientation, but when the speed ofthe vehicle does not change the hubcap is stationary (provided that the bearings are sufficiently lubricated).

[0005] A disadvantage ofthe hubcap described by Park is that the orientation ofthe hubcap is not completely constant but known as ‘floating’.

[0006] Another disadvantage is that electrical connections, necessary for sensors or displays needing electricity (here referred to as an electronic display, even when only comprising a LED) or transferring data from the hubcap to the part of the vehicle at the other side of the suspension or vice versa are not possible.

[0007] A sensor-holding hubcap is known from European patent publication EP1327534B1 to SKF Industrie SpA, further referred to as SKF. Here a stator located at the side ofthe wheel assembly that is connected to the suspension supports the rotor, and this stator comprises a recess where a sensor can be mounted at the side of the wheel assembly that is connected to the suspension. This recess is covered by the hubcap and is well sealed to avoid moisture and dirt entering the recess.

[0008] A disadvantage ofthe hubcap according to SKF is that it is not normally visible from the side of the car. This makes this hubcap unusable for displays or sensors needing access to the side ofthe car removed from the suspension, for example proximity sensors.

[0009] There is a need for a stationary (non-floating) hubcap, more specifically for a hubcap that can make a robust electrical contact with a part of the vehicle located at the side remote from the suspension.

[0010] The invention intends to provide a solution to this need.

Disclosure of the invention.

[0011] To that end a wheel assembly according to the invention is characterized in that, when the hubcap is removed, the stator is accessible from the second side through the rotor and the hubcap is mounted fixedly on the stator, the hubcap showing one or more displays and/or sensors.

[0012] By connecting the hubcap fixedly on a (stationary) part of the stator extruding, or at least being accessible, through the rotor, a hubcap that is really stationary is created.

[0013] Although in hindsight this may seem an obvious solution, it is noted that Park (with a priority date of 2 February 1988) does not teach that the stationary part is connected to the suspension ofthe vehicle and/or a stator. Instead Park teaches a ‘floating’ display. Also, other publications teach ‘floating’ displays, or (in the case of SKF) a hubcap with a sensor at the inside of the vehicle (the side where the wheel assembly connects to the suspension). This may be caused by the prejudice that the central axis of the wheel assembly should also be the rotation axle, the axle rotating with respect to the suspension.

It can thus be concluded that until now no solution was known to mount a hubcap on the second side of the wheel assembly that has a really stationary orientation with respect to the suspension, and thereby the vehicle.

[0014] In an embodiment of the wheel assembly according to the invention the wheel assembly is a wheel assembly comprising an in-wheel motor, and the rotor and the stator are part of the in-wheel motor.

[0015] Inventor recognized that, when using an in-wheel motor for a vehicle, such as an Axial Field Permanent Magnet motor or a Radial Field Permanent Magnet motor, the stator is accessible at the side removed from the side that connects to the suspension. Typically, the stator even protrudes through the rotor. This makes this type of wheel assembly well suited as a powered wheel assembly with a stationary hubcap according to the invention.

[0016] In another embodiment of the wheel assembly according to the invention the vehicle is a car, a lorry or a truck.

[0017] In yet another embodiment of the wheel assembly according to the invention the one or more displays are electronic displays.

[0018] By selecting electronic displays, for example backlighted screens, the ‘message’ on the hubcap can change. This enables changes of the display, logo, or information displayed.

[0019] It is noted that in this context ‘electronic display’ includes displays comprising only a LED or another such simple illumination device, but also includes pixelated displays such as for example LCD displays, TFT displays, etc., where a number of pixels form a logo, or such like. The display may form the outside of the hubcap, but may also be protected by, for example, safety glass.

[0020] In still another embodiment of the wheel assembly according to the invention electrical wiring travel from the second side to the first side and from there to the vehicle, the wiring for supplying power and/or data to the one or more displays and/or sensors. [0021] Preferably the one or more displays and/or sensor(s) are powered by a simple power connection from the vehicle, for example a 12V power supply. By leading the wiring through the stator and/or a groove in the stator, the wiring can travel from the second side to the first side, and from there to the vehicle. If a data connection is needed as well, for example via a CAN bus, this can follow the same or a similar route.

[0022] In a further embodiment of the wheel assembly according to the invention at least one electronic display at least temporarily displays status information of the vehicle.

[0023] The display can display can display information about the car. For an electric car such information can be, for example, the charge condition of the car.

[0024] The invention also seeks protection for a vehicle equipped with one or more wheel assemblies according to the invention.

[0025] The invention also seeks protection for a hubcap for use with any of the wheel assemblies according to the invention.

[0026] As a hubcap for use with a wheel assembly could be produced, imported, and sold separate from the wheel assembly, the invention expressly seeks protection for the hubcap ‘as such’ as well.

Brief description of the figures.

[0027] The invention is now elucidated using figures, in which identical reference signs indicate corresponding features. To that end:

Figure 1 schematically shows a non-powered wheel assembly according to the invention, Figure 2A schematically shows a round hubcap according to the invention,

Figure 2B schematically shows a rectangular hubcap according to the invention, and Figure 3 schematically shows a wheel assembly with an in-wheel motor according to the invention.

Figure 4 schematically shows a wheel assembly with an in-wheel motor according to the invention, further showing a protective wheel cover.

Detailed description ofthe invention.

[0028] Figure 1 schematically shows a non-powered wheel assembly according to the invention.

A non-powered wheel assembly 100 comprises an axle in the form of stator 102 that is connected to the suspension of a vehicle (not shown) located at side A via flange 104. Flange 104 is secured to the suspension system (not shown) A with bolts (not shown) using screw-thread 106. The stator supports a rotor 108 via bearing 110, as a result of which the rotor is rotatable around rotation axis 112. The rotor in turn supports the rim 114 with a tire 116 mounted thereon. The rim is secured to the rotor by screws 118.

The stator 102 or axle is thus formed as a dead axle.

On the rotor 108 a disk 120 of a disk brake is secured using screws 122. The caliper of the disk brake is not shown.

A hubcap 150 is fixedly mounted on the stator 102 on side B. As the stator is connected to the suspension (via flange 104), the orientation ofthe hubcap is fixed as well.

[0029] By forming a groove in the axle 102 (the stator) a channel can be made where electric wires can be fed from the suspension (not shown) at side A through the inner shell of the bearing 110 to side B of the bearing 110, and from there to the stationary hubcap 150.

[0030] It is noted that the hubcap need not be rotationally symmetric. Also, for example, rectangular hubcaps are envisaged. Any asymmetry does not influence the wheel balance, as the hubcap is not part of the rotating part of the wheel.

[0031] Figure 2A schematically shows a round hubcap according to the invention. Figure 2A shows a round (that is: with a rotationally symmetric outline) hubcap 202 as seen from side B of figure 1. It shows a display area 210, where, for example, a logo can be displayed. If electric connections are made to the hubcap, such a logo can be an illuminated logo, and for example the color can be changed as well.

In a second area 212 an indication of, for example, the temperature can be shown, either as a temperature in degrees Celsius (or in degrees Fahrenheit), or a symbol indicating snow, frost, or other weather conditions. Such a weather condition can be derived from (temperature) measurements from a sensor on the car, or for example taken from the internet. For an electric car also the load condition of the battery may be shown here, either as a percentage, or in a color coding, e.g. showing a red color for a low charge condition and green for fully charged.

A third area 214 comprises a sensor, for example a proximity sensor, used to warn the driver, or in the case of an autonomously driven car, a controller in the car, that an obstacle, or a person, is close to the wheel. Also, the proximity of a curb can be detected in this way.

[0032] Figure 2B schematically shows a rectangular hubcap according to the invention, Figure 2B can be thought to be derived from figure 2A, but now the round hubcap 202 is replaced by a rectangular hubcap 204.

[0033] It is noted that the center of gravity need not intercept with the rotational axis 112, as the hubcap does not interfere with the wheel balance. Also other forms, such as triangular, free form, or animal head can be used.

[0034] Figure 3 schematically shows a wheel assembly with an in-wheel motor according to the invention.

[0035] Figure 3 can be thought to be derived from figure 1. Figure 3 shows wheel assembly 300 with an Axial Field Permanent Magnet motor, where a stator 302 is surrounded by a rotor 306. The single bearing shown in figure 1 is replaced by dual bearings 310 and 312. On the rotor several corner parts 304 are mounted, which carry the rim 114. In the rotor 306 a number of permanent magnets 308 are inserted, and the stator shows a number of electromagnets 314 with magnetic pole pieces 316. The principle of a Axial Field Permanent Magnet motor is well known, as is the almost identical principle of a Radial Field Permanent Magnet motor. Also, other motors are known where the stator is available at the second side.

[0036] For the invention it is relevant that the stator is available from the second side, indicated by B, and that a hubcap can be mounted. Here as well electric connection can be made from the first side, side A, to the hubcap by grooves in the inner shell of bearings 310 and 312. A hole through the stator gives easy passage between the two bearings.

[0037] It is noted that the displays can be illuminated signs, logo’s or such, but can also take the form of a screen showing a multitude of pixels, the pixels capable to show said signs, logo’s, etc.

[0038] Figure 4 schematically shows a wheel assembly with an in-wheel motor according to the invention, further showing a protective wheel cover.

[0039] Figure 4 can be thought to be derived from figure 3. Added it shows a wheel cover (460) that locally shows a window (462) that is transparent to light and/or radiation used by displays and/or sensors. Hereby the wheel bearing at the second side (110), the displays and the sensors are protected from dirt and water. Preferably the wheel cover is mounted to the rotor using a hermetic seal, for example using an O-ring (not shown) placed in a groove in either the rotor or the wheel cover. The wheel cover can be mounted on the rotor using, for example, screws, or using an adhesive. As sensors may use, for example, light or infrared, the material of the window should be chosen accordingly. The window (462) should preferably have a size sufficiently large so that the displays and/or sensors are visible through the window in any orientation of the rotor with respect to the stator or hubcap.