Friction ring for wheel brake disc of rail vehicle

Abstract

The invention relates to a friction ring (1) for a wheel brake disc of a rail vehicle, comprising a friction surface (2) and a rear surface (3) facing away from the friction surface, from which a plurality of cooling webs (6, 7, 10, 11) extend in a direction perpendicular to the friction surface (2), at least some of the cooling webs (6, 7, 10, 11) being designed as first cooling webs (6), and at least some of the cooling webs (6, 7, 10, 11) being designed as second cooling webs (6, 7, 10, 11). The first cooling web has a cross-section (Q) which tapers away from the rear side (3) parallel to the plane viewed from the rear side (3) and transitions into a circle.

Description

Technical Field

[0001] The invention relates to a friction ring for a wheel brake disc of a rail vehicle according to the preamble of claim 1 .

[0002] The invention also relates to a wheel brake disc for a rail vehicle. Background Art

[0003] Similar friction rings and wheel brake discs for rail vehicles are disclosed, for example, in DE 10 2019 118216 A1 or DE 10 2020 112 874 A1. Such friction rings are usually fixed to the spokes of the wheel body of a rail wheel by screwing.

[0004] In such friction rings, the highest possible cooling capacity is important. This cooling capacity is achieved primarily by cooling ribs arranged radially on the back of such friction rings, which ensure a high air flow and thus good cooling due to the fan effect. Summary of the Invention

[0005] The object of the present invention is to further optimize the cooling capacity of friction rings for wheel brake disks of rail vehicles.

[0006] This object is achieved by a friction ring for a wheel brake disc of a rail vehicle having the features of claim 1 .

[0007] Furthermore, the stated object is achieved by a wheel brake disc for a rail wheel of a rail vehicle having the features of claim 8 .

[0008] The friction ring according to the invention for a wheel brake disk of a rail vehicle comprises a friction surface and a rear side facing away from the friction surface, from which a plurality of cooling ribs extend in a direction perpendicular to the friction surface.

[0009] At least some of the cooling webs are designed as first cooling webs having a cross section that tapers away from the rear side in a plane viewed parallel to the rear side and transitions into a circle.

[0010] A cooling rib designed in this way has, at least in its cylindrical section, an optimally circular cross section which provides a large surface area while at the same time offering sufficient free area for the air flow.

[0011] Furthermore, a cooling rib of this shape, due to its larger cross-section compared to the free end, is so stable at the transition to the rear side of the friction ring that it can withstand the machining required, in particular after casting the friction ring, to obtain a smooth end face of the first cooling rib, which supports the friction ring on a rail wheel of a rail vehicle.

[0012] Advantageous embodiments of the invention are the subject of the dependent claims.

[0013] According to an advantageous embodiment of the present invention, the first cooling fin has a base protruding from the back side and a neck extending from the base, the cross-section of the base in the circumferential direction of the friction ring being larger than the cross-section radially to the imaginary rotation axis of the friction ring, and the head having a circular cross-section.

[0014] The base is oriented such that its longitudinal extension is greatest in the circumferential direction of the friction ring, which enables a particularly stable design of the first cooling web.

[0015] The circumferential surface of the first cooling web preferably transitions seamlessly from the base into the neck.

[0016] According to an advantageous embodiment variant, the first cooling webs are arranged one behind the other in the circumferential direction and thus form a substantially circular support for the friction ring on the rail wheel of the rail vehicle.

[0017] The first cooling ribs are preferably arranged successively in the circumferential direction near the inner edge and / or near the outer edge of the friction ring. In particular, an arrangement of the first cooling ribs near both the inner edge and the outer edge of the friction ring not only ensures stable support of the friction ring on the wheel brake of the rail vehicle, but also enables an optimized cooling geometry.

[0018] Regarding the design of the first cooling fin itself, in a preferred embodiment variant, the ratio between the maximum length at the base of the first cooling fin and the diameter at the neck of the first cooling fin (viewed in a plane parallel to the rear surface) is between 1.2 and 2.5.

[0019] According to another preferred embodiment, a portion of the cooling ribs is configured as second cooling ribs having a circular cross section in a plane parallel to the rear side, wherein the height extension of the second cooling ribs perpendicular to the rear side plane is smaller than the height extension of the first cooling ribs.

[0020] These second cooling webs are therefore used only for cooling the friction rings.

[0021] According to another preferred embodiment variant, fifth cooling webs designed as cooling ribs are integrally formed between two rows of first cooling webs, viewed in the circumferential direction, and extend over almost the entire radial width of the friction ring.

[0022] In a preferred embodiment, cylindrically shaped third cooling ribs and projections are arranged distributed between two rows of first cooling ribs, viewed in the radial direction.

[0023] According to another embodiment, when viewed in the radial direction, a sixth cooling fin for accommodating a screw part is integrally formed between the two rows of first cooling fins. In addition to the screw part accommodating area, the sixth cooling fin also has a fin connected to the screw part accommodating area, extending radially inward, and having a contact surface. The contact surface of the sixth cooling fin is located on an imaginary circumferential line with the contact surfaces of the first cooling fin and the fifth cooling fin.

[0024] The wheel brake disk according to the invention for a rail wheel of a rail vehicle comprises two friction rings fastened to opposite sides of the rail wheel and is characterized in that the friction rings are designed as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The preferred embodiments are described in detail below with reference to the accompanying drawings.

[0026] Figure 1 An isometric view of a friction ring according to the prior art with cooling webs designed as cooling ribs is shown;

[0027] Figure 2 A corresponding isometric view of the back side of a friction ring according to the invention is shown, which has first cooling ribs arranged close to the inner edge and close to the outer edge of the friction ring;

[0028] Figure 3 Show Figure 2 A partial enlarged view of the friction ring is shown to illustrate the structure of the first cooling fin;

[0029] Figure 4 An isometric view of an alternative embodiment of a friction ring according to the invention is shown, which has a first cooling web arranged close to the inner edge of the friction ring;

[0030] Figure 5 Another isometric view showing an alternative embodiment of a friction ring according to the invention having first cooling ribs arranged near the inner edge and near the outer edge of the friction ring; and

[0031] Figure 6 Show Figure 5 A partial top view of the friction ring is shown. DETAILED DESCRIPTION

[0032] In the following description of the figures, terms such as top, bottom, left, right, front, and rear, etc., refer only to exemplary illustrations and positions of friction rings, friction surfaces, back surfaces, cooling ribs, etc., selected in the respective figures. These terms are not to be understood as restrictive, i.e., these relationships can be varied due to different operating positions or mirror-symmetrical designs, etc.

[0033] Figure 1The back side of a friction ring known from the prior art is shown, which has a plurality of cooling webs 140 formed as cooling ribs, as well as screw receptacles 180 integrally formed on the cooling ribs and cams 190 likewise connected to the cooling ribs, by means of which good cooling of such a friction ring is already achieved.

[0034] Figure 2 A corresponding illustration shows a friction ring 1 according to the invention, which has a rear side 3 facing away from the friction surface of the friction ring 1 , which is designated by reference numeral 2 .

[0035] The wheel brake disk preferably comprises a pair of such friction rings 1 , one friction ring 1 being fixed to each of opposite sides of the rail wheel.

[0036] Extending from the rear side 3 of the friction ring 1 are a plurality of cooling ribs 6, 7, 10, 11 and a screw receptacle 8 having a cylindrical circumferential surface, through which corresponding screws can be screwed into a rail wheel of a rail vehicle from the side of the friction surface 2 in order to secure the friction ring 1 to the rail wheel of the rail vehicle.

[0037] Furthermore, a projection 9 is integrally formed on the rear side 3 , which has a groove 92 extending radially to the imaginary axis of rotation of the rail wheel or of the friction ring 1 mounted thereon, and which serves to accommodate a sliding block (not shown here) which is arranged on a rail wheel of the rail vehicle and serves to support the friction ring 1 on the rail wheel of the rail vehicle.

[0038] As in Figure 2 It can also be seen that the cooling webs 6, 7 are not designed as cooling ribs, but as approximately cylindrical cooling webs. The first cooling web 6 is designed here with a cross section that tapers away from the rear side 3 in a plane viewed parallel to the rear side 3 and transitions into a circle.

[0039] The second cooling tab 7 is constructed as a cooling tab having a continuous cylindrical shape. All cooling tabs 6, 7, 10 and cooling tab 11 (as in Figure 4 ) is preferably formed integrally directly on the friction ring 1 by a casting process.

[0040] Apart from the cams 9 and the end faces of the screw receptacles 8 , the first cooling webs 6 for contacting the friction ring 1 on the wheel brakes of the rail vehicle usually need to be reworked after the casting process in order to obtain a very flat contact surface 63 at the free end of the first cooling web 6 .

[0041] As in Figure 3 As can be clearly seen in FIG, the first cooling rib 6 is configured with a base 61 protruding from the rear side and a neck 62 extending from the base 61 away from the rear side 3 .

[0042] The base 61 is designed to be approximately oval in cross section in a plane viewed parallel to the rear side 3. F The maximum extension, ie its maximum length L, in the preferred embodiment variant shown here, extends in the circumferential direction of the friction ring 1 and is greater than the maximum cross-sectional width in the radial direction (viewed radially relative to the imaginary rotation axis of the friction ring 1 ).

[0043] Starting from the rear side 3 , a neck extends preferably steplessly from a base 61 until the base 61 transitions into a cylindrical neck 62 , the end of which forms a contact surface 63 for contacting a rail wheel of a rail vehicle.

[0044] It is also conceivable that the base cross section is oriented in such a way that it is larger in the radial direction than in the circumferential direction.

[0045] like Figure 2 As further shown, the first cooling ribs 6 are arranged one behind the other in the circumferential direction.

[0046] Preferably, a row of such first cooling ribs 6 extends successively in the circumferential direction close to the inner edge 4 of the friction ring 1 and preferably a row of such first cooling ribs extends successively in the circumferential direction close to the outer edge 5, as in Figure 2 As shown in .

[0047] exist Figure 4 In the alternative embodiment shown in FIG, such first cooling webs 6 are provided only close to the inner edge 4 of the friction ring 1 .

[0048] exist Figure 2 A plurality of cylindrical second cooling fins 7 are integrally formed between two rows of first cooling fins 6 .

[0049] Viewed perpendicularly to the plane of the rear side 3 , the height extension H7 of the second cooling ribs 7 is smaller than the height extension H6 of the first cooling ribs 6 .

[0050] The ratio between the maximum length L at the base 61 of the first cooling fin 6 and the diameter d1 at the neck 62 of the first cooling fin 6 is particularly preferably between 1.2 and 2.5. This ratio enables an optimized cooling capacity while ensuring a high stability of the first cooling fin 6.

[0051] exist Figure 4 In the alternative embodiment shown in , T-shaped cooling ribs 11 are integrally formed on the rear side 3 of the friction ring 1 close to the outer edge 5 , which cooling ribs enable a particularly stable mounting of the friction ring 1 on a rail wheel of a rail vehicle.

[0052] exist Figure 5 and Figure 6In another alternative embodiment shown in , the first cooling webs 6 are again arranged both close to the inner edge 4 and close to the outer edge 5 of the friction ring 1 .

[0053] Fifth cooling webs 12 , designed as cooling ribs, are integrally formed between the two rows of first cooling webs 6 , viewed in the circumferential direction, and extend over nearly the entire radial width of the friction ring 1 .

[0054] These fifth cooling ribs 12 also have, at their ends, contact surfaces 121 for contacting rail wheels of a rail vehicle, as viewed in the radial direction. The recessed regions 122 extending between the contact surfaces 121 are lower in height than the contact surface 121 regions, so that air can flow between the recessed regions 122 and the rail wheels.

[0055] Furthermore, in this embodiment variant, Figure 2 and Figure 4 Similar to the embodiment variant shown in , the cylindrical third webs 10 and the projections 9 are distributed. Instead of the screw receptacle 8, a sixth cooling web 13 for receiving a screw is also integrally formed here. In addition to a screw receptacle area 132, the sixth cooling web has a web connected to the screw receptacle area, extending radially inward, and having another contact surface 131. The contact surface 131 is located on an imaginary circumferential line with the contact surface 63 of the first cooling web 6 and the contact surface 121 of the fifth cooling web.

[0056] Reference Signs List

[0057] 1 friction ring

[0058] 2 friction surface

[0059] 3 Back

[0060] 4 inner edge

[0061] 5 outer edge

[0062] 6First cooling fin

[0063] 61 base

[0064] 62 Neck

[0065] 63 contact surface

[0066] 7 Second cooling tab

[0067] 8 screw member receiving portion

[0068] 9 bumps

[0069] 91 Circumference

[0070] 92 grooves

[0071] 10 Third cooling tab

[0072] 11 Fourth cooling tab

[0073] 12 Fifth cooling tab

[0074] 121 contact surface

[0075] 122 sinking area

[0076] 13 Sixth cooling tab

[0077] 131 contact surface

[0078] 132 Threaded parts receiving area

[0079] Q cross section

[0080] Q F Base cross section

[0081] L is the maximum length of the base.

Claims

1. A friction ring (1) for a wheel brake disc of a rail vehicle, the friction ring having a friction surface (2) and a back side (3) facing away from the friction surface, a plurality of cooling ribs (6, 7, 10, 11, 12, 13) extending from the back side in a direction perpendicular to the friction surface (2), characterized in that: At least some of the cooling fins (6, 7, 10, 11, 12, 13) are designed as first cooling fins (6) having a cross section (Q) which tapers away from the rear side (3) in a plane viewed parallel to the rear side (3) and transitions into a circle.

2. The friction ring (1) according to claim 1, characterized in that The first cooling fin (6) has a base (61) protruding from the back surface (3) and a neck (62) extending from the base, and the cross section (Q F ) has a dimension in the circumferential direction of the friction ring (1) that is greater than a dimension radially relative to an imaginary rotation axis of the friction ring (1), and the neck (62) is constructed with a circular cross section (Q).

3. The friction ring (1) according to claim 2, characterized in that The circumferential surface of the first cooling web (6) transitions from the base (61) to the neck (62) without any step.

4. The friction ring (1) according to any one of the preceding claims, characterized in that The first cooling ribs (6) are arranged one after the other in the circumferential direction.

5. The friction ring (1) according to claim 4, characterized in that The first cooling webs (6) are arranged successively in the circumferential direction close to the inner edge (4) and / or close to the outer edge (5) of the friction ring (1).

6. The friction ring (1) according to any one of the preceding claims, characterized in that The ratio between the maximum length (L) at the base (61) of the first cooling fin (6) and the diameter (d1) at the neck (62) of the first cooling fin (6) is between 1.2 and 2.

5.

7. The friction ring (1) according to any one of the preceding claims, characterized in that A portion of the cooling fins (6, 7, 10, 11) is configured as a second cooling fin (7), the second cooling fin having a circular cross-section in a plane observed parallel to the back side (3), the height extension of the second cooling fin (7) perpendicular to the plane of the back side (3) being smaller than the height extension of the first cooling fin (6).

8. The friction ring (1) according to any one of the preceding claims, characterized in that Viewed in the circumferential direction, fifth cooling webs (12) configured as cooling ribs are integrally formed between two rows of first cooling webs (6), and extend over almost the entire radial width of the friction ring (1).

9. The friction ring (1) according to claim 8, characterized in that Viewed in the radial direction, cylindrical third cooling fins (10) and cams (9) are distributed between two rows of first cooling fins (6).

10. The friction ring (1) according to claim 8 or 9, characterized in that When viewed in the radial direction, a sixth cooling fin (13) for accommodating a screw part is integrally formed between two rows of first cooling fins (6). In addition to a screw part accommodating area (132), the sixth cooling fin also has a fin connected to the screw part accommodating area (132), extending radially inward, and having an abutment surface (131). The abutment surface (131) of the sixth cooling fin (13) is located on an imaginary circumferential line together with the abutment surface (63) of the first cooling fin (6) and the abutment surface (121) of the fifth cooling fin (12).

11. A wheel brake disc for a rail wheel of a rail vehicle, the wheel brake disc having two friction rings (1) fastened to opposite sides of the rail wheel, characterized in that: The friction ring (1) is constructed according to one or more of the preceding claims.

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