Wheel brake discs for rail vehicles

Abstract

The wheel brake disc (2) is arranged on either side of the plate part (1a) of the wheel body (1) of the railway wheel and comprises at least two friction discs (2a, 2b) fixed by a fixing element (4b), the at least two friction discs (2a, 2b) having a number of cooling fins and a fixing dome (4), the fixing element (4b) extending through the fixing dome (4) and the plate part (1a) of both friction discs (2a, 2b). The at least two friction discs (2a, 2b) have a number of round pillars (10, 10a, 10b) and at least one annular fin (12) as cooling fins.

Description

[Technical field]

[0001] The invention relates to a wheel brake disc for railway vehicles according to the preamble of claim 1 .

[0002] Such wheel brake discs for railway vehicles are usually mounted on the wheel body of the railway wheel.

[0003] In figures 1-2 this is shown in a schematic partial excerpt of a schematic radial section of a wheel body 1 with a plate portion 1a, an axis 1b and a prior art wheel brake disc 2. In figure 3 a schematic plan view of the rear surface R of the friction discs 2a, 2b of the prior art wheel brake disc 2 shown in figures 1-2 is further shown.

[0004] The wheel brake disc 2 has two friction discs 2a, 2b with respective friction surfaces RF. On the rear surfaces R of the friction discs 2a, 2b, regularly distributed over a diameter, a number of fixing domes 4 with respective contact surfaces AF and respective through holes 4a extend parallel to the direction of the axis 1b. Both friction discs 2a, 2b are fastened together to the wheel disc or plate part 1a of the wheel body 1 by means of fixing elements 4b extending through the through holes 4a, in the illustrated configuration by through screws.

[0005] The rotation of the friction discs 2a, 2b relative to the wheel disc or plate 1a is normally prevented by sliders (not shown) arranged radially in the radial grooves 19. These sliders take up all forces applied tangentially to the wheel disc, for example friction forces between brake pads (not shown but easily imaginable) and the friction discs 2a, 2b, and transmit these forces into the wheel body 1 of the corresponding wheel.

[0006] The wheel brake disc 2 is provided with a number of cooling fins 3, which increase the cooling surface area in the cooling passages K between the cooling fins 3 and between the cooling fins 3 and the dome 4, while at the same time have a high ventilation action which generally results in a high and effective cooling action during rotation of the wheel brake disc 2. The ventilation action of the cooling fins 3 achieves ventilation of air which is sucked into the cooling passages K through an air inlet 7 at the inner diameter 5 of each of the friction discs 2a, 2b and which, due to the centrifugal force caused by the rotation, exits the cooling passages as an air flow 7a through an air outlet 8 at the outer diameter 6 of the friction discs 2a, 2b in the radial direction as an air flow 8a.

[0007] 3 shows this together with the distribution of the cooling fins 3 and the fixed domes 4 on the rear surface R of the friction discs 2a, 2b. The cooling fins 3 extend substantially radially from the inner diameter 5 to the outer diameter 6. In the region of the fixed domes 4, the cooling fins 3 are divided by the respective fixed domes 4 into two parts.

[0008] The cooling fins 3 are arranged with a contact surface for contact with the plate portion 1a. On the middle diameter a fixing dome 4 is arranged, also with a contact surface for contact with the plate portion 1a.

[0009] 4 and 5 show further examples according to the prior art for friction discs 2a, 2b with different cooling fins 3, 3a to 3e.

[0010] In FIG. 4, the cooling fins 3 extend linearly in the radial direction of the friction discs 2 a , 2 b and are not interrupted by the fixed domes 4 .

[0011] FIG. 5 shows the cooling fins 3a-3e distributed on five coaxial circles between the inner diameter 5 and the outer diameter 6 of the friction discs 2a, 2b as arc sections each having a different arc length.

[0012] Figure 6 shows a schematic perspective view of an axle brake disc 2 according to the prior art with so-called round pillars 9. Figure 7 further shows a partial excerpt of the axle brake disc 2. In the illustrated configuration, the round pillars 9 have a biconical shape with a smaller diameter arranged in the middle of each round pillar 9. The air outlets 8 for the outgoing air flow 8a form a gap SP, which is formed between the friction discs 2a, 2b on their outer diameter 6 by two round pillars 9 in each case. The length of the gap SP is the distance between the rear faces R of the friction discs 2a, 2b.

[0013] With regard to the high fan loss power generated, the inability to mention efficient cooling is considered a drawback.

[0014] SUMMARY OF THE PRESENT EMBODIMENT It is therefore an object of the present invention to provide an improved wheel brake disc having reduced fan power losses and improved cooling of the wheel brake disc.

[0015] This problem is solved by the subject matter of claim 1.

[0016] The idea of ​​the invention is to maximize the surface area of ​​the friction disc within the cooling passage while at the same time keeping the air entraining effect of this surface area increasing element small.

[0017] The wheel brake disc according to the invention comprises at least two friction discs arranged on either side of a plate part of a wheel body of a railway wheel and fixed by a fixing element, the at least two friction discs having a number of cooling fins and a fixing dome, the fixing element extending through the fixing dome and the plate part of both friction discs, the at least two friction discs having a number of round pillars and at least one annular fin as cooling fins.

[0018] The wheel brake disc according to the invention thereby benefits from a combination of design features: the ventilation of the air sucked into the cooling passage at the inner diameter of the friction disc and emerging radially at the outer diameter of the cooling passage due to the centrifugal forces caused by the rotation is throttled, while at the same time advantageously the volume of ventilated air is obtained which efficiently cools the friction disc which is heated up during braking.

[0019] In this way, the surface area of ​​the friction disc can be maximized within the cooling passages by means of a number of round pillars, while at the same time keeping the air carrying effect of this surface area increasing element small.

[0020] In one configuration, the round pillars are arranged on circles having different diameters on the at least two friction discs, and the at least one annular fin is arranged as a circumferentially extending annular fin on a circle having a diameter that lies along an outer diameter of each of the at least two friction discs.

[0021] In terms of flow technology, these round pillars achieve a swirling of the radially flowing air, which in turn leads to a highly efficient thermodynamic heat transfer to the air turbulence thus generated in relation to the volume of air being conveyed.

[0022] In order to advantageously throttle the amount of air conveyed, annular fins are selected which at the same time provide the further advantage that a further increase in the effective cooling surface area is also achieved by means of the annular fins themselves in the cooling passages.

[0023] Another configuration specifies that at least two friction discs have separate round pillars connected to each other by annular fins, which is advantageous since the effective cooling surface area is thus increased and furthermore the annular fins are reinforced.

[0024] In this case, it is specified that the round pillars connected to each other by the annular fins are arranged at regular angular intervals from each other, the angular intervals having an angular value in the range of 3° to 15°, preferably 5° to 10° or preferably 5°, which results in an advantageously stable structure.

[0025] In another configuration, the round pillars connected to one another by the annular fins may have a cylindrical cross section, which allows for an advantageously simple construction. Other cross sections are of course also possible.

[0026] In yet another embodiment, the round pillars connected to one another by the annular fins extend beyond the rear surface of the friction disc by a specific, predefinable dimension in the axial length, thus advantageously influencing the air outlet.

[0027] For this purpose, in another embodiment, it is specified that each section of the annular fin between the two round pillars and the plate of the wheel body to be assigned forms an opening as a gap for the air outlet. In this case, a particular advantage is that the main function is the formation of a gap between the friction disk and the plate of the railway wheel. This gap at the air outlet from the cooling channel can be individually made wider or narrower depending on the requirements of different concepts.

[0028] Further advantageous configurations are set forth in the dependent claims.

[0029] In a further embodiment, the round pillars connected to one another by annular fins each have a contact surface for applying against the corresponding plate section of the wheel body, which advantageously results in a stable construction.

[0030] If the first round pillar has a contact surface for abutting against the plate portion of the wheel body to be assigned and the second and third round pillars are formed shorter than the first round pillar by a certain dimension in the axial direction, it is advantageously possible to obtain a stable structure with air transport and the imparting of vortices to the air flow.

[0031] In yet another configuration, a first round pillar having a contact surface is disposed on a first circle having a first diameter, the first circle being located along an inner diameter of each friction disc.

[0032] In another configuration, it is specified that the round pillar has a conical shape with its maximum diameter located on the rear surface of the at least two friction discs, which can have a beneficial effect on the air conveyance and the imparting of swirl to the air flow.

[0033] In the following, several embodiments of the present invention will be described with reference to the accompanying drawings. These embodiments are merely used to describe the present invention based on several preferred structures, but these structures do not constitute the present invention exclusively. To the extent that, other embodiments as well as modifications and equivalents of the illustrated embodiments are possible within the scope of the claims. [Brief description of the drawings]

[0034] [Figure 1] FIG. 1 is a schematic partial excerpt of a schematic radial cross-section of a wheel body with a wheel brake disc according to the prior art; [Diagram 2] FIG. 1 is a schematic partial excerpt of a schematic radial cross-section of a wheel body with a wheel brake disc according to the prior art; [Diagram 3] FIG. 3 is a schematic plan view of the underside of the friction disc of the prior art wheel brake disc shown in FIGS. 1-2; [Figure 4] FIG. 1 is a schematic plan view of a wheel brake disc according to the prior art; [Diagram 5] FIG. 1 is a schematic plan view of a wheel brake disc according to the prior art; [Figure 6] FIG. 1 is a schematic diagram of an axle brake disc according to the prior art; [Figure 7] FIG. 1 is a schematic diagram of an axle brake disc according to the prior art; [Figure 8] FIG. 2 is a schematic perspective view of the rear surface of a friction disc of a wheel brake disc according to the present invention; [Figure 9] FIG. 2 is a schematic perspective view of the rear surface of a friction disc of a wheel brake disc according to the present invention; [Figure 10] FIG. 10 is a schematic partial excerpt of a schematic radial cross-sectional view of a wheel body provided with the wheel brake disc according to the present invention shown in FIGS. 8 and 9. [Figure 11] FIG. 11 is a schematic partial side view of the wheel brake disc according to the present invention shown in FIGS. 8 to 10.

[0035] 1-7 have already been discussed above.

[0036] Fig. 8 shows a schematic perspective view of the rear surface R of the friction discs 2a, 2b of the wheel brake disc 2 according to the present invention. Fig. 9 shows an enlarged partial excerpt of the friction discs 2a, 2b shown in Fig. 8. Fig. 10 shows a schematic partial excerpt of a schematic radial cross section of a wheel body 1 equipped with a wheel brake disc 2 according to the present invention. Fig. 11 shows a schematic partial side view of the friction discs 2a, 2b of the wheel brake disc 2 according to the present invention shown in Figs. 8 to 10.

[0037] The friction disc 2a, 2b shown in Fig. 8 is divided in the radial direction, for better understanding, into four circles with diameters 14, 15, 16, 17 and is defined by an inner diameter 5 and an outer diameter 6. The smallest diameter is the inner diameter 5, followed by four diameters 14, 15, 16, 17 in ascending order up to the outer diameter 6. A first circle with a first diameter 14 is located along the inner diameter 5.

[0038] A number of sectors 20, 20a are distributed over the friction discs 2a, 2b. In the illustrated version, only two of these sectors 20, 20a are labeled by way of example. Each sector 20, 20a is defined by two imaginary radial separation lines. On each separation line, one of the twelve fixed domes 4 is arranged by way of example in the illustrated version. The angle between the two separation lines of each sector 20, 20a is 30° in the illustrated version. The sectors 20, 20a differ from one another firstly in that radial grooves 19 are arranged between the sectors 20a.

[0039] The fixed domes 4 are arranged at equal angular intervals from one another, for example on a diameter 18 which is the mid-diameter of the friction discs 2a, 2b.

[0040] To form surface area increasing elements in the cooling passage K (see FIG. 9), so-called round pillars 10, 10a, 10b have been selected in the illustrated configuration.

[0041] These round pillars 10, 10a, 10b achieve, in terms of flow technology, the imparting of vortices to the radially flowing air, which in turn generates a highly efficient thermodynamic heat transfer to the air in relation to the volume of air being conveyed, in other words a turbulent air flow with a higher heat transfer than a laminar air flow is generated.

[0042] The round pillars 10, 10a, 10b are attached to or integrally formed on circles having different diameters 14, 15, 16, 17 on the rear surface R of the friction discs 2a, 2b. The round pillars 10, 10a, 10b protrude in the axial direction from the rear surface R of the friction discs 2a, 2b.

[0043] The first round pillar 10 is disposed at a first diameter 14 , the second round pillar 10 a is disposed at a second diameter 15 , and the third round pillar 10 b is disposed at a third diameter 16 .

[0044] The first round pillars 10 are arranged on the first diameter 14 in groups of three within sector 20 and in groups of two within sector 20a.

[0045] A second round pillar 10 a is present between the two fixed domes 4 only within the sector 20 on the second diameter 15 .

[0046] And on the third diameter 16, the third round pillars 10b are arranged in groups of three within sector 20 and in groups of two within sector 20a.

[0047] The round pillars 10, 10a, 10b have a conical shape with the maximum diameter located on the surface of the back surface R in the illustrated configuration. The axial lengths of the round pillars 10, 10a, 10b are different in the illustrated configuration. Thus, the first round pillar 10 has a contact surface AF that contacts the plate portion 1a of the wheel body 1. The second and third round pillars 10a, 10b are shorter than the first round pillar 10 and have a gap between their upper surface and the plate portion 1a. This can be seen in FIG. 11.

[0048] In order to throttle the volume of air being conveyed, an annular fin 12 arranged on the fourth diameter 17 is selected so as to extend circumferentially close to the outer diameter 6 of the friction discs 2a, 2b.

[0049] The annular fin 12 has an outer surface 12a facing towards the outer diameter 6 and an inner surface 12b. The annular fin 12 connects together a number of round pillars 11 with a cylindrical cross section. In the illustrated example, there are 66 round pillars 11. In this case, within the sector 20a, each one of the round pillars 11 is omitted due to a radial groove. The round pillars 11 are arranged at regular angular intervals from one another. In this example, the angular interval between the round pillars is 5°. The angular interval may have an angular value lying, for example, in the range of 3° to 15°, preferably 5° to 10°.

[0050] The round pillars 11 extend beyond the annular fins 12 from the rear surfaces R of the friction discs 2a, 2b by a specific predefined dimension in the axial length and have contact surfaces AF for abutting against the plate portion 1a. Thus, each section of the annular fin 12 between each of the two round pillars 11 and the plate portion 1a forms an opening 13.

[0051] The annular fin 12 itself also achieves a further increase in the effective cooling surface area in the cooling channel K. In this case, the main function is the formation of a gap SP between the friction discs 2a, 2b and the plate part 1a of the wheel body 1. This gap SP can be clearly seen in Fig. 10. The gap SP is the distance between the openings 13 of the annular fin 12 between the two round pillars 11 at the air outlet 8 from the cooling channel K and can be made wider or narrower individually depending on the different application cases.

[0052] The throttling of the air volume or air flow 7a is shown enlarged in Figure 9. The air flow 7a from the air inlet 7 flows towards the annular fin 12 and is redirected on the one hand axially upwards over the annular fin 12 through openings 13 as air flow 8a into the air outlet 8. On the other hand, the air flow 7a is split upon impact with the inner surface 12b of the annular fin 12 into separate air flows 8b tangentially to the left and right.

[0053] The wheel brake disc 2 therefore has a high possible cooling effect of the friction discs 2a, 2b at the same time as a low fan loss power due to air ventilation in the region of the cooling passage K between the friction discs 2a, 2b and the wheel body 1.

[0054] The invention is not limited to the embodiments described above but it can be modified within the scope of the claims. [Explanation of symbols]

[0055] 1 Wheel body 1a plate part 1b axis 2 Wheel brake discs 2a, 2b Friction disc 3,3a,3b,3c,3d,3e cooling fins 4 Fixed Dome 4a through hole 4b Fixed elements 5 Inner diameter 6 Outer diameter 7 Air inlet 7a Air flow 8 Air outlet 8a, 8b Air flow 9;10,10a,10b;11 round pillar 11a Top side 12 Annular fin 12a Exterior 12b Inside 13 Opening 14,15,16,17,18 diameter 19 Radial groove 20,20a fan shape AF contact surface K cooling passage R Back RF friction surface SP gap

Claims

1. A wheel brake disc (2) comprising at least two friction discs (2a, 2b) arranged on either side of a plate portion (1a) of a wheel body (1) of a railway wheel and fixed by a fixing element (4b), the at least two friction discs (2a, 2b) having a plurality of cooling fins and a fixing dome (4), the fixing element (4b) extending through the fixing dome (4) and the plate portion (1a) of both friction discs (2a, 2b), Wheel brake disc (2), characterized in that the at least two friction discs (2a, 2b) have a plurality of round pillars (10, 10a, 10b) and at least one annular fin (12) as cooling fins.

2. 2. The wheel brake disc (2) according to claim 1, characterized in that the round pillars (10, 10a, 10b) are arranged on circles having different diameters (14, 15, 16) on the at least two friction discs (2a, 2b) and the at least one annular fin (12) is arranged as a circumferentially extending annular fin (12) on a circle having a diameter (17) located along the outer diameter (6) of each of the at least two friction discs (2a, 2b).

3. Wheel brake disc (2) according to claim 2, characterized in that the at least two friction discs (2a, 2b) have further round pillars (11) connected to each other by the annular fins (12).

4. 4. The wheel brake disc (2) according to claim 3, characterized in that the round pillars (11) connected to one another by the annular fins (12) are arranged at regular angular intervals from one another, said angular intervals having an angular value lying in the range of 3° to 15°, preferably 5° to 10° or suitably being 5°.

5. Wheel brake disc (2) according to claim 3 or 4, characterized in that the round pillars (11) connected to one another by the annular fins (12) have a cylindrical cross section.

6. 6. The wheel brake disc (2) according to claim 3, wherein the round pillars (11) connected to each other by the annular fins (12) protrude in their axial length beyond the rear surface (R) of the friction disc (2a, 2b) by a specific, predefinable dimension.

7. 7. The wheel brake disc (2) according to claim 6, characterized in that each part of the annular fin (12) between each of the two round pillars (11) and the plate part (1a) of the wheel body (1) to be assigned forms an opening (13) as a gap (SP) for an air outlet (8).

8. The wheel brake disc (2) according to any one of claims 3 to 7, characterized in that the round pillars (11) connected to each other by the annular fins (12) each have a contact surface (AF) for abutting against the plate portion (1a) of the wheel body (1) to be assigned thereto.

9. The wheel brake disc (2) according to any one of claims 1 to 8, characterized in that the first round pillar (10) has a contact surface (AF) for abutting against the plate portion (1a) of the wheel body (1) to be assigned, and the second and third round pillars (10a, 10b) are formed shorter than the first round pillar (10) by a certain dimension in the axial direction.

10. 8. Wheel brake disc (2) according to claim 7, characterized in that the first round pillar (10) with its contact surface (AF) is arranged on a first circle having a first diameter (14), which first circle is located along the inner diameter (5) of each of the friction discs (2a, 2b).

11. Wheel brake disc (2) according to any one of claims 1 to 10, characterized in that the round pillar (10, 10a, 10b) has a conical shape with its maximum diameter located on the rear surface (R) of the at least two friction discs (2a, 2b).

Images