Patent ID: 12203517

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS OF THE INVENTION

FIG.1illustrates a vehicle1, in accordance with at least one exemplary embodiment of the invention. Although the vehicle1is illustrated in the form of a truck, other types of vehicles, such as busses, construction equipment, trailers or passenger cars may be provided in accordance with the invention.

The truck (vehicle) comprises a cab2in which a driver may operate the vehicle1. The vehicle1comprises a number of road wheels4, herein illustrated as two pairs of wheels, however in other embodiments there may be a different number of wheels, such as three pairs, four pairs or more. In the cab2a driver may press a brake pedal with his/her foot in order to activate the brake or brakes. Activation of the brake causes brake pads to be pressed against an inventive brake disc (not illustrated inFIG.1) connected via a wheel end hub to an axle that rotates the road wheels4.

FIG.2illustrates a brake disc10according to at least one exemplary embodiment, mounted on a wheel end hub20.FIG.3illustrates an exploded view of the brake disc10inFIG.2.FIG.4illustrates a cross-sectional view of the brake disc10inFIG.2.FIG.5is an enlarged view ofFIG.4. The brake disc10is configured to be connected via the wheel end hub20to a vehicle axle (not illustrated) and to be squeezed between brake pads (not illustrated).

With reference toFIGS.2-5and, for explanatory reasons in particular with reference to the exploded view ofFIG.3, the brake disc comprises a central disc body30having a first side32and a second side34(seeFIGS.4and5). The second side34faces in the opposite direction compared to the first side32. The brake disc10comprises a first disc plate36and a second disc plate38, each disc plate36,38having a wear surface40for producing friction when a brake pad is pressed against the wear surface40. The wear surfaces40face away from the central disc body30. Each disc plate also has an oppositely facing, i.e. a disc body facing surface42. In the exploded view ofFIG.3, the wear surface40of the first disc plate36and the disc body facing surface42of the second disc plate38are visible.

The first disc plate36is releasably secured to the first side32of the central disc body30and the second disc plates38is releasably secured to the second side34of the central disc body30. When the first and second disc plates36,38have been sufficiently worn out, they may easily be replaced with new disc plates, without needing to dismount the central disc body30from the wheel end hub20. An enveloping sleeve50may be releasably secured to an outer circumference52(seeFIG.3) of the central disc body30so as to apply a radially inwardly directed pressure to the first and second disc plates36,38. The enveloping sleeve50may be replaced by other peripherally applied means, such as clamps for supporting the disc plates36,38.

The central disc body30is substantially circular and ring-shaped having a central opening through which the wheel end hub20may protrude. The central disc body30will thus be supported by the wheel end hub20, while the removable disc plates36,38are or will be mounted to the central disc body30. The central disc body30may suitably be provided with cooling channels to allow air to circulate and cool the brake disc10. InFIG.3cooling channel apertures54are visible on the radially outer circumference52of the central disc body30. Said radially outer circumference52may also be referred to as the radially outer periphery of the central disc body30. In this connection, it should be noted that the brake disc10has a geometrical centre axis x around which it rotates with the wheel axle. The geometrical centre axis x may thus also be referred to as a rotational axis. Radial directions are thus directions running perpendicularly away from the geometrical centre axis x. Circumferential directions run around the geometrical centre axis x. Axial directions extend along or in parallel with the geometrical centre axis x. In the cross-sectional view ofFIG.4, cooling channel apertures54are visible at the radially inner periphery56of the central disc body30.

As best seen inFIG.3,FIG.4andFIG.5the central disc body30may be provided with a plurality of passages58in the form of through holes which extend all the way from the first side32of the central disc body30to the second side34of the central disc body30. The function of the passages58will be explained further down in this description. As can be seen inFIG.3, the plurality of passages58are distributed along two concentric imaginary circles, and are arranged in pairs along radii in different radial directions from the geometrical centre axis. Thus, each passage58in the inner imaginary circle is paired along a radius from the geometrical centre axis with a passage58in the outer imaginary circle. It should be noted that in other embodiments the passages58may be distributed differently and need not be paired or distributed along imaginary circles. It should furthermore be noted that although a plurality of passages58are illustrated in the exemplary embodiments of the drawings, in other embodiments the number of such passages may be fewer, for example just one passage.

The central disc body30may on each one of the first and second sides32,34have an annular ledge60near its inner periphery56at the central hole, for supporting the first and second disc plates36,38, respectively (seeFIG.3andFIG.5). The two ledges60may be referred to as first and second ledges60for receiving the first and second disc plates36,38, respectively.

The first and second disc plates36,38are also ring-shaped and thus the wheel end hub will extend through the central hole of the first and second disc plates36,38as well. The first and second disc plates36,38may be made of any suitable friction material (metallic, ceramic, etc.) and/or may be provided with a coating surface providing appropriate frictional properties. As can be seen inFIG.3, the first and second disc plates36,38may be provided with a plurality of holes62having a distribution pattern which corresponds to the distribution pattern of the plurality of passages58.

FIG.3illustrates a plurality of connecting members64which are configured to be inserted into said passages58of the central disc body30, each connecting member64fitting into one of said passages58. As can be seen inFIG.4andFIG.5, the length of the connecting members64may be such that they extend partly into the holes62of the first and second disc plates36,38, but preferably not to the wear surface40of the disc plates36,38. Suitably, the length of the connecting members64is shorter than the acceptable wear thickness of the disc plates36,38. Put differently, if the disc plates36,38are envisaged to be replaced when they have worn down to a certain reduced thickness compared to their initial thickness, at such reduced thickness the connecting members64should still be short from the worn surface. The function of the connecting members64is to prevent relative rotation between the disc plates36,38and the central disc body30. It should be understood that although a plurality of connecting members64have been illustrated, it is conceivable (similarly to the above discussion concerning the passages58) to have fewer connecting members64, such as a single connecting member64. Since the central disc body30is suspended from the wheel end hub, and the first and second disc plates36,38may in turn be suspended from the central disc body30, the disc plates36,38could run the risk of rotating relative to the central disc body30, resulting in a lower braking capacity. By providing a connecting member64(or a plurality of connecting members64) which interconnect the central disc body30with both the first disc plate36and the second disc plate38, relative rotation is efficiently counteracted, without the disadvantages resulting from using separate screws for each one of the disc plates and the exposure of screw heads at the wear surfaces40.

In the illustrated embodiments, a first plurality of connecting members64extend in a first plurality of passages58which are distributed along an imaginary outer circle, and a second plurality of connecting members64extend in a second plurality of passages58which are distributed along an imaginary inner circle. Other patterns are of course also conceivable.

The connecting members64, which are herein illustrated as pins, may suitably be resilient in the radial direction. For instance, they may be compressed when inserted into the first and second disc plates36,38and central disc body30, and then expand so as to provide a tight fit with the walls defining the passages58in the central disc body30. In some exemplary embodiments, said passages58through the central disc body30has a cross-sectional area which substantially corresponds to the cross-sectional area of the connecting members64.

It should be understood that the disc plates do not necessarily need to have through holes62for accommodating the ends of the connecting members64, it would also be conceivable to have blind bores extending from the disc body facing surface42. Thus, in a general sense, each one of the first and second disc plates36,38may comprise one or more cavities for housing a respective end of the one or more connecting members64, regardless of the cavities being in the form of blind bores or through holes.

As can be seen in the drawings, in the illustrated exemplary embodiments, the width of the enveloping sleeve50is greater than the width of the outer circumference52of the central disc body30. Suitably, as seen in the drawings, the enveloping sleeve50covers the first and the second disc plates36,38, i.e. its width substantially corresponds to the total width (or thickness) of the radially outer peripheries of the disc plates36,38and the central disc body30. However, in other exemplary embodiments, the enveloping sleeve50may have a smaller width and only partly covering the width of the disc plates36,38. In still other exemplary embodiments, the enveloping sleeve50may have an even smaller width wherein it may provide a force onto the disc plates36,38via one or more other components which at least partly cover the outer peripheries of the disc plates36,38.

The enveloping sleeve50has been illustrated as forming a complete circle around the outer circumference of the central disc body (and around the disc plates), although other configurations are conceivable. As best seen inFIG.3andFIG.5, the enveloping sleeve50has a circular central portion70flanked on either side by two edge portions72extending from the central portion70to a respective edge74. Each one of the edge portions72has a mating surface76for mating with the outer periphery78of the first and second disc plates36,38, respectively (outer periphery78is indicated inFIG.3). Each one of the mating surfaces76are inclined relative to the geometrical centre axis for counteracting axial movement of the disc plates36,38relative to the central disc body30. The angle of inclination may for instance be 5°-80° relative to the geometrical centre axis, for instance 10°-50°, such as 15°-30°.

In the illustrated embodiments, the thickness of each one of the edge portions72of the enveloping sleeve50increases from the central portion70towards the respective edge74.

The inclination of the mating surfaces76is such that it slopes towards the geometrical centre axis as it extends away from the central disc body30. Thus, for each one of said mating surfaces76, the distance between the geometrical centre axis and the mating surface76is relatively larger adjacent to the central portion70of the enveloping sleeve50and relatively smaller adjacent to the respective edge74of the enveloping sleeve50.

In a corresponding manner, the outer periphery78of each disc plate36,38(which outer periphery78extends from the wear surface40to an oppositely located disc body facing surface42) tapers in a direction from the disc body facing surface42towards the wear surface40, wherein said mating surfaces76of the enveloping sleeve50has the same angle of taper as said outer periphery78of the first and second disc plates36,37, respectively.

Each one of the first and second disc plates36,38has an inner periphery80(seeFIG.3) extending from the wear surface40to the disc body facing surface42. The inner periphery80may be tapered, and suitably also the mating ledge60(seeFIG.5) of the central disc body30is inclined with the same angle as said taper of the inner periphery80of the disc plates36,38. The ledge60on each side is thus adapted to receive said inner periphery80of a respective one of the disc plates36,38. The ledge60comprises a free end61and a connected end63. As illustrated inFIG.5, the ledge60may suitably be inclined such that the distance between its free end61and the geometrical centre axis is greater than the distance between its connected end63and the geometrical centre axis.

The enveloping sleeve50may be secured by fastening means to the central disc body. For instance, as illustrated in the exemplary embodiment ofFIG.6, the fastening means82may be or may comprise bolts, screws of rivets, which may be loosened when the enveloping sleeve is to be removed so as to allow replacement of worn disc plates. However, in other exemplary embodiments, the fastening means may not be visible from the outside, such as for instance in the form of mutually cooperating snap fit portions on the enveloping sleeve and the central disc body, respectively (this may for instance be the case inFIG.2). In other exemplary embodiments, there is no need for any particular fastening means, the enveloping sleeve my form a very tight fit with the central disc body and the disc plates, for instance providing a radially inward pressure of the disc plates towards an inclined ledge (such as the above discussed ledge60) to counteract axial movement of the disc plates relative to the central disc body.

As also illustrated in the exemplary embodiment ofFIG.6, the number of connecting members, passages and holes may be different in different embodiments. InFIG.6, for instance, only one hole62is shown for inserting a single connecting member into one passage of the central disc body. It should thus be understood that features from any one of the herein described embodiments, whether discussed under the heading “Summary” or under the heading “Detailed Description of Example Embodiments of the Invention”, may as long as they are compatible, be freely adapted to and implemented in any other one of the exemplary embodiments. For instance, the fastening means82in the exemplary embodiment ofFIG.6may be implemented for the brake disc10in the exemplary embodiment ofFIG.2.

FIG.7illustrates an exploded view of a brake disc according to at least a further exemplary embodiment. This embodiment has most features in common with the exemplary embodiment ofFIG.3, and therefore, common features are represented by the same reference numerals.

In the exemplary embodiment ofFIG.7the first disc plate36is made up by three separate disc plate segments36a,36b,36c, which may be individually mounted to the central disc body30. Once mounted, they make up the complete first disc plate36. Similarly the second disc plate38is made up by three separate disc plate segments38a,38b,38c, which may be individually mounted to the central disc body30. Using a plurality of disc plate segments (i.e. two or more disc plate segments) to make up a complete disc plate may facilitate the mounting procedure, in particular if the disc plate is to be fitted to an inclined ledge60of the central disc body30.

FIG.7also illustrates a segmented enveloping sleeve50. The enveloping sleeve50is made up by three separate enveloping sleeve segments50a,50b,50c, which may be individually mounted to the outer circumference52of the central disc body30. Once mounted, they make up the complete enveloping sleeve50. Using a plurality of enveloping sleeve segments (i.e. two or more enveloping sleeve segments) to make up a complete enveloping sleeve may facilitate the mounting procedure, in particular if the enveloping sleeve50has tapered edges72which mate with the outer periphery78of the disc plates36,38(which may have a corresponding taper).

It should be understood that the segmented disc plates36,38and the segmented enveloping sleeve50shown inFIG.7, may in other exemplary embodiments be combined with other features than illustrated inFIG.7. For instance, according to at least some exemplary embodiments, the brake disc may comprise segmented first and second disc plates, and a non-segmented enveloping sleeve, such as the enveloping sleeves illustrated in the previously discussed drawing figures. Likewise, according to at least some exemplary embodiments, the brake disc may comprise a segmented enveloping sleeve and non-segmented first and second disc plates, such as the disc plates illustrated in the previously discussed drawing figures. The number of connecting members64, passages58and holes62may also be different than illustrated inFIG.7. For instance, in some exemplary embodiment there may be only one connecting member for each pair of disc plate segments.

It is to be understood that the present invention is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims.