Friction ring for a wheel brake disc and wheel brake disc for a rail vehicle
The friction ring for rail vehicle brake discs uses round bars and T-shaped ribs to enhance cooling efficiency by optimizing air flow and surface area, addressing inefficiencies in existing designs.
Patent Information
- Application Number
- DE102023116722
- Authority / Receiving Office
- DE · DE
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-06-26
- Publication Date
- 2025-01-02
AI Technical Summary
Existing friction rings for wheel brake discs in rail vehicles suffer from inefficient cooling due to high fan power loss, despite having a good cooling effect.
The friction ring design incorporates a combination of round bars and T-shaped ribs that maximize cooling surface area while throttling air ventilation to enhance thermodynamic heat transfer and turbulence, reducing fan power loss.
This design achieves efficient cooling with reduced fan power loss by optimizing air flow and increasing cooling surface area, resulting in improved thermal management for the brake disc.
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Abstract
Description
[0001] The present invention relates to a friction ring for a wheel brake disc of a rail vehicle according to the preamble of claim 1. The invention further relates to a wheel brake disc for a rail wheel of a rail vehicle.
[0002] Such friction rings, for example known from DE 10 2020 112 874 A1, are usually attached to a wheel body of a rail wheel.
[0003] Fig. Figure 1 shows a schematic partial section of another conventional design of such a wheel brake disc for rail vehicles, known from the prior art. Such a friction ring is attached to each side of a web 21 of a wheel body 2.
[0004] The wheel brake disc shown consists of two friction rings 3, each with a friction surface 31. On a rear side 32 facing away from the friction surface, a plurality of cooling webs and fastening domes 5 extend in a direction perpendicular to the friction surfaces 31.
[0005] The two friction rings 3 are fastened to the web 29 of the wheel body 2 by means of fastening elements 4, which here are designed as screws. These fastening elements 4 extend through the fastening domes 5 of both friction rings 3 and the web 21 of the wheel body 2, in order to clamp the friction rings 3 against the web 21 of the wheel body 2 using the fastening elements 4.
[0006] Rotation of the friction rings on the wheel body 2 is usually prevented by radially arranged sliding blocks (not shown) in radial grooves 91 of cams 9. These also absorb all forces on the wheel body 2 in the tangential direction, for example the wheel force between a brake pad (not shown) and the respective friction ring 3, and transmit these to the wheel body 2 of the associated wheel.
[0007] The friction rings 3 further comprise a plurality of cooling ribs, which also extend perpendicularly to the friction surface 31 of the respective friction ring 3. These cooling ribs increase the cooling surface in cooling channels between the cooling ribs and mounting domes 5 and, at the same time, exhibit a high ventilation effect upon rotation of the friction ring 3, which generally leads to a high and effective cooling effect.
[0008] The ventilation effect of the cooling webs causes a ventilation of the air, which is sucked into the cooling channels at a respective inner diameter 11 of the friction rings 3 through air inlets and, as a result of the centrifugal force caused by rotation, exits radially as air flows at an outer diameter 12 of the friction ring 3.
[0009] The disadvantage of the friction rings known from the state of the art is that, in view of the high fan power loss generated, an efficient cooling effect cannot be spoken of.
[0010] The object of the present invention is therefore to provide an improved friction ring for a wheel brake disc of a rail vehicle, with reduced fan power loss while at the same time maintaining a good cooling effect of the friction ring.
[0011] The object is achieved by a friction ring for a wheel brake disc of a rail vehicle having the features of claim 1.
[0012] A friction ring according to the invention for a wheel brake disc of a rail vehicle has a friction surface and a rear side facing away from the friction surface, from which a plurality of cooling webs and fastening domes extend in a direction perpendicular to the friction surface.
[0013] A first part of the cooling bars is designed as round bars.
[0014] A second part of the cooling webs is designed as T-shaped ribs, viewed parallel to a plane of the friction surface.
[0015] The T-shaped ribs are arranged radially outside and / or inside the fastening domes along an imaginary circular line whose center is an axis of rotation of the friction ring.
[0016] Such a friction ring is characterized in particular by the fact that the ventilation of the air which is sucked into the cooling channel at the inner diameter of the friction ring and exits radially at the outer diameter of the cooling channel as a result of the centrifugal force caused by rotation is throttled and at the same time it is advantageous that the ventilated air quantity efficiently cools the friction disc which is heated during braking.
[0017] The surface area of the friction ring in the cooling channel is maximized by the round webs. At the same time, the T-shaped ribs minimize the airflow effect of these surface-enlarging elements.
[0018] Advantageous embodiments of the invention are the subject of the subclaims.
[0019] According to an advantageous embodiment, the T-shaped ribs have radial webs extending radially to the axis of rotation of the friction ring and transverse webs oriented perpendicularly thereto.
[0020] In a preferred embodiment, a portion of the T-shaped ribs are arranged on a circle having a diameter adjacent to an outer edge of the friction ring.
[0021] It is further preferred that, alternatively or additionally, a portion of the T-shaped ribs are arranged on a circle having a diameter which adjoins an inner edge of the friction ring.
[0022] In the case of the T-shaped ribs arranged near the outer edge of the friction ring, at least in the case of a majority of these T-shaped ribs, free ends of the radial webs are closer to the outer edge than the transverse webs.
[0023] The same preferably applies to the number of T-shaped ribs arranged near the inner edge of the friction ring. Accordingly, the free ends of the radial webs are preferably closer to the inner edge than the transverse webs of the T-shaped ribs.
[0024] The round webs are preferably arranged on circles with different radii.
[0025] The round webs cause a turbulence in the radially flowing air, which, with regard to the amount of air conveyed, results in a very efficient thermodynamic heat transfer to the turbulent air flow thus generated.
[0026] T-shaped fins were chosen to effectively throttle the air flow. These T-shaped fins also offer the additional advantage of further increasing the cooling surface area in the cooling channel.
[0027] The round webs preferably have a circular-cylindrical cross-section.
[0028] In a particularly preferred embodiment, diameters of the round webs viewed parallel to the surface of the back of the friction ring are designed to decrease from a largest diameter on the surface of the back of the friction ring towards their free ends.
[0029] This can have a beneficial effect on the air flow and the turbulence of the air flows.
[0030] The wheel brake disc according to the invention for a rail wheel of a rail vehicle, which has at least two friction rings arranged on both sides of a web of a wheel body of the rail wheel and fastened by means of fastening elements, wherein the fastening elements extend through the fastening domes of both friction rings and the web, is characterized by friction rings as described above.
[0031] Preferred embodiments are explained in more detail below with reference to the attached drawings.
[0032] They show: Fig. 1 a schematic partial section of a radial sectional view of a wheel body with a friction ring according to the prior art, Fig. 2 a schematic perspective view of a rear side of a friction ring according to the invention and Fig. 3 a schematic plan view of the Fig. 2 shown friction ring.
[0033] In the following description of the figures, terms such as top, bottom, left, right, front, rear, etc., refer exclusively to the exemplary representation and position of the friction ring, wheel body, web, fastening elements, ribs, and the like chosen in the respective figures. These terms are not to be understood as limiting; i.e., these references may change due to different operating positions or the mirror-symmetrical design, etc.
[0034] The friction ring known from the state of the art Fig. 1 has already been described above in the introduction to the description.
[0035] Fig. 2 shows a schematic perspective view of a rear side 32 of a friction ring 3 according to the invention.
[0036] Fig. 3 shows the back side 32 of the friction ring 3 according to Fig. 2 in a top view.
[0037] As in Fig. 2, the friction ring 3 has, on its rear side 32 facing away from a friction surface 31, a plurality of cooling webs and fastening domes 5 which extend in a direction perpendicular to the friction surface 31.
[0038] A first part of these cooling bars is designed as round bars 8.
[0039] A second part of these cooling webs is designed as T-shaped ribs 6, 7, viewed parallel to a plane of the friction surface 31.
[0040] How to continue in the Fig. 2 and Fig. 3, the T-shaped ribs 6, 7 are arranged radially outside and / or inside the fastening domes 5 along an imaginary circular line, the center of which is an axis of rotation 34 of the friction ring 3.
[0041] In the embodiment shown, the fastening domes 5 are arranged centrally in the radial direction of the friction ring 3
[0042] On the same radius as the fastening domes 5, cams 9 with radial grooves 31 are preferably also formed, which serve to guide the above-mentioned sliding blocks (not shown).
[0043] The T-shaped ribs 6, 7 have radial webs 61, 71 extending radially to the axis of rotation 34 of the friction ring 3 and transverse webs 62, 72 aligned perpendicularly thereto.
[0044] How to continue in the Fig. 2 and Fig. 3, a partial number of the T-shaped ribs 6, 7 are arranged on a circle with a diameter adjacent to an outer edge 12 of the friction ring 3 (T-shaped ribs 6).
[0045] A further number of the T-shaped ribs 6, 7 are arranged on a circle with a diameter that borders the inner edge 11 of the friction ring 3 (T-shaped ribs 7).
[0046] The orientation of the T-shaped ribs 6, 7 is predominantly such that the free ends of the radial webs 61 in the T-shaped ribs 6 close to the outer edge 12 of the friction ring 3 are closer to the outer edge 12 than the transverse webs 62.
[0047] The same applies to the T-shaped ribs 7 close to the inner edge 11 of the friction ring 3. Here, too, the free ends of the radial webs 71 of the T-shaped ribs 7 are closer to the inner edge 11 than the transverse webs 72.
[0048] As in Fig. 3, there are a few T-shaped ribs 6 close to the outer edge 12, in the embodiment shown there are two T-shaped ribs 6, which are aligned such that the transverse web 62 is closer to the outer edge 12 than the free end of the radial web 61. This "inverted" alignment creates a support area on the outer edge 12 radially outside the corresponding T-shaped rib 6, which is used in the manufacturing process, for example to align the friction ring 3 for turning on a turntable.
[0049] The round bars 8 are, as shown in the Fig. 2 and Fig. 3, arranged on circles with different radii 13, 14, 15.
[0050] The round webs 8 preferably have a circular-cylindrical cross-section.
[0051] Preferably, these round webs 8 are preferably conically shaped in their longitudinal extension in a direction Z, ie a diameter of the round webs 8 viewed parallel to the surface of the rear side 32 of the friction ring 3 is designed to decrease from a largest diameter on the surface of the rear side 32 of the friction ring 3 in the direction of their free ends.
[0052] Depending on the circumferential spacing of the fastening domes 5 in a circumferential direction U, different groupings of round webs 8 are realized in order, on the one hand, to create the largest possible cooling surface in the cooling channels and, on the other hand, to ensure good turbulence of the air cooling air flowing through. List of reference symbols 2 wheel bodies 21 jetty 22 axis of rotation 3 friction ring 31 Friction surface 32 Back 33 contact surface 34 axis of rotation 4 Fastening element 5 Mounting dome 51 through hole 6 ribs 61 Radial web 62 crossbar 7th rib 71 Radial web 72 crossbar 8 round bridge 9 cams 91 Radial groove 11 inner edge 12 Outer edge 13 radius 14 radius 15 radius R Radial direction U circumferential direction Z thickness direction QUOTES CONTAINED IN THE DESCRIPTION
[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature
[0000] DE 10 2020 112 874 A1
[0002]
Claims
[1] Friction ring (3) for a wheel brake disc of a rail vehicle, with a friction surface (31) and a rear side (32) facing away from the friction surface, from which a plurality of cooling webs and fastening domes (5) extend in a direction perpendicular to the friction surface (31), wherein a first part of the cooling webs is designed as round webs (8), characterized by in that a second part of the cooling webs is designed as T-shaped ribs (6, 7) viewed parallel to a plane of the friction surface (31), wherein the T-shaped ribs (6, 7) are arranged radially outside and / or inside the fastening domes (5) along an imaginary circular line, the center of which is an axis of rotation (34) of the friction ring (3). [2] Friction ring (3) according to claim 1, characterized by that the T-shaped ribs (7) have radial webs (61, 71) extending radially to the axis of rotation (34) of the friction ring (3) and transverse webs (62, 72) aligned perpendicularly thereto. [3] Friction ring (3) according to claim 1 or 2, characterized by that a partial number of the T-shaped ribs (6, 7) are arranged on a circle with a diameter which borders on an outer edge (12) of the friction ring (3). [4] Friction ring (3) according to claim 1 or 2, characterized by that a partial number of the T-shaped ribs (6, 7) are arranged on a circle with a diameter which borders on an inner edge (11) of the friction ring (3). [5] Friction ring (3) according to claim 3, characterized by that at least in the case of a majority of the T-shaped ribs (7), free ends of the radial webs (71) are closer to the inner edge (11) than the transverse webs (72). [6] Friction ring (3) according to claim 4, characterized by that at least in the case of a majority of the T-shaped ribs (6), free ends of the radial webs (61) are closer to the outer edge (12) than the transverse webs (62). [7] Friction ring (3) according to one of the preceding claims, characterized bythat the round webs (8) are arranged on circles with different radii (13, 14, 15). [8] Friction ring (3) according to one of the preceding claims, characterized by that the round webs (8) have a circular-cylindrical cross-section. [9] Wheel brake disc (2) according to one of the preceding claims, characterized by that the diameters of the round webs (8) viewed parallel to the surface of the back (32) of the friction ring (3) decrease from a largest diameter on the surface of the back (32) of the friction ring (3) towards their free ends. [10] Wheel brake disc for a rail wheel of a rail vehicle, comprising at least two friction rings (3) arranged on either side of a web (21) of a wheel body (2) of a rail wheel and fastened by means of fastening elements (4), wherein the fastening elements (4) extend through the fastening domes (5) of both friction rings (3) and the web (21), characterized bythat the friction rings (1) are designed according to one or more of the preceding claims.
Citation Information
Patent Citations
Wheel brake disc for rail vehicles
DE102020112874A1
Rotor for ventilated disc brakes
DE3120104A1
brake disc
DE9319490U1
Brake disc
WO2022210831A1
