Wheel brake discs for railway 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 a railway vehicle 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] 1-2 show this 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. Figure 3 also shows a schematic plan view of the rear surfaces R of the friction discs 2a, 2b of the prior art wheel brake disc 2 shown in Figures 1-2.

[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, a number of fixing domes 4, regularly distributed over one diameter and each with a respective contact surface AF and a respective through-hole 4a, extend parallel to the direction of the axis 1b. Both friction discs 2a, 2b are fastened together to the wheel disc or plate 1a of the wheel body 1 by means of fixing elements 4b, which in the illustrated configuration are through-holes 4a, extending through the through-holes 4a.

[0005] 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 absorb all forces applied tangentially to the wheel disc, for example the friction forces between the 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 plurality of cooling fins 3. These cooling fins 3 increase the cooling surface area in the cooling passages K between them and between the cooling fins 3 and the dome 4, while at the same time providing a high ventilation action which generally results in a high and effective cooling action when the wheel brake disc 2 rotates. The ventilation action of the cooling fins 3 ensures that air is drawn into the cooling passages K through air inlets 7 at the inner diameter 5 of each of the friction discs 2a, 2b and, due to the centrifugal force caused by the rotation, exits the cooling passages as air flow 7a through air outlets 8 at the outer diameter 6 of the friction discs 2a, 2b in the radial direction as 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 into two parts by each fixed dome 4.

[0008] The cooling fins 3 are arranged with a contact surface for contact with the plate portion 1a. On the intermediate diameter, a fixing dome 4 is arranged 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 a prior art axle brake disc 2 with so-called round pillars 9. Figure 7 also shows a partial view of the axle brake disc 2. In the illustrated configuration, the round pillars 9 have a biconical shape with the smaller diameter located midway between the two round pillars 9. The air outlets 8 for the outgoing air flow 8a form gaps SP, which are formed by two round pillars 9 in each case between the friction discs 2a, 2b on their outer diameter 6. The length of the gaps SP is the distance between the rear surfaces 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 INVENTION It is therefore an object of the present invention to provide an improved wheel brake disc with reduced fan power losses and increased cooling of the wheel brake disc.

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

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

[0017] The wheel brake disc according to the present 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 plurality of cooling fins and a fixing dome, the fixing element extending through the fixing dome and the plate part of both friction discs, and the at least two friction discs having a plurality 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 air drawn into the cooling channel at the inner diameter of the friction disc and escaping radially at the outer diameter of the cooling channel due to the centrifugal force caused by rotation is throttled, while at the same time advantageously ensuring that the volume of vented air efficiently cools the friction disc, which is heated during braking.

[0019] In this way, the surface area of ​​the friction disc can be maximized within the cooling passages by the 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 of 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 is located along the outer diameter of each of the at least two friction discs.

[0021] These round pillars achieve flow engineering by creating swirl in 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 additional advantage that the annular fins themselves also achieve a further increase in the effective cooling surface area within the cooling passage.

[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 this increases the effective cooling surface area and also reinforces the annular fins.

[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, with this angular interval having an angle value in the range of 3° to 15°, preferably 5° to 10°, or preferably 5°, which results in an advantageously stable structure.

[0025] Alternatively, the round pillars connected to one another by 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 a further 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 amount in their axial length, thereby advantageously influencing the air outlet.

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

[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 bearing against the corresponding plate of the wheel body, which advantageously results in a stable construction.

[0030] If the first round pillar has a contact surface for contacting 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 achieve 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 the inner diameter of each friction disc.

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

[0033] Several embodiments of the present invention will be described below with reference to the accompanying drawings. These embodiments are merely used to explain the present invention based on several preferred structures, but these structures do not constitute the exclusive scope of the present invention. To the extent that other embodiments and modifications and equivalents of the illustrated embodiments are possible within the scope of the claims. [Brief explanation of the drawings]

[0034] [Figure 1] 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; [Figure 2] 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; [Figure 3] FIG. 3 is a schematic plan view of the rear surface of the friction disc of the prior art wheel brake disc shown in FIGS. 1 and 2. [Figure 4] 1 is a schematic plan view of a wheel brake disc according to the prior art; [Figure 5] 1 is a schematic plan view of a wheel brake disc according to the prior art; [Figure 6] 1 is a schematic diagram of a prior art axle brake disc; [Figure 7] 1 is a schematic diagram of a prior art axle brake disc; [Figure 8] 1 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] 1 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 described above.

[0036] Figure 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. Figure 9 shows an enlarged partial excerpt of the friction discs 2a, 2b shown in Figure 8. Figure 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. Figure 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 Figures 8 to 10.

[0037] The friction discs 2a, 2b shown in Figure 8 are radially divided into four circles with diameters 14, 15, 16, 17 for better understanding and are 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 plurality of sectors 20, 20a are distributed over the friction discs 2a, 2b. In the illustrated configuration, only two of these sectors 20, 20a are illustratively numbered. Each sector 20, 20a is defined by two imaginary radial separation lines. In the illustrated configuration, one of the twelve fixed domes 4 is arranged on each separation line. The angle between the two separation lines of each sector 20, 20a is 30° in the illustrated configuration. The sectors 20, 20a differ from each other 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 on a diameter 18, which is for example the mid-diameter of the friction discs 2a, 2b.

[0040] To form the 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 flow engineering by creating vortices in the radially flowing air, which results in 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 is created, which results in a higher heat transfer than laminar air flow.

[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 axially 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] The 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 the sector 20 and in groups of two within the sector 20a.

[0047] In the illustrated configuration, the round pillars 10, 10a, and 10b have a conical shape with their maximum diameter located on the surface of the rear surface R. In the illustrated configuration, the round pillars 10, 10a, and 10b have different axial lengths. 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 and 10b are shorter than the first round pillar 10, and there is a gap between their upper surfaces and the plate portion 1a. This can be seen in Figure 11.

[0048] To throttle the amount of air being conveyed, annular fins 12 arranged on the fourth diameter 17 are selected 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 the outer diameter 6 and an inner surface 12b. The annular fin 12 connects a number of round pillars 11 having a cylindrical cross section. In the illustrated example, there are 66 round pillars 11. In this case, within each sector 20a, one round pillar 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 angle value, 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 predetermined specific dimension in the axial length, and each have a contact surface AF for contacting 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 serves to further increase the effective cooling surface area within the cooling channel K. In this case, its main function is to form a gap SP between the friction discs 2a, 2b and the plate portion 1a of the wheel body 1. This gap SP can be clearly seen in Figure 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 may be made wider or narrower depending on the different application cases.

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

[0053] The wheel brake disc 2 therefore has the highest possible cooling effect of the friction discs 2a, 2b, while at the same time having 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 can be varied 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 Airflow 8 Air Outlet 8a, 8b Air flow 9;10,10a,10b;11 round pillar 11a Top side 12 Annular fin 12a Exterior 12b Inner surface 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), 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; 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 on a circle having a diameter (17) located along the outer diameter (6) of each of the at least two friction discs (2a, 2b); Wheel brake disc (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).

2. 2. The wheel brake disc (2) according to claim 1, 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, the angular intervals having an angular value in the range of 3° to 15°, preferably 5° to 10° or suitably 5°.

3. Wheel brake disc (2) according to claim 1 or 2, characterized in that the round pillars (11) connected to one another by the annular fins (12) have a cylindrical cross section.

4. 3. The wheel brake disc (2) according to claim 1 or 2, characterized in that the round pillars (11) connected to each other by the annular fins (12) extend beyond the annular fins (12) from the rear surface (R) of the friction disc (2a, 2b) in their axial length by a specific, predefinable dimension.

5. 5. The wheel brake disc (2) according to claim 4, characterized in that each portion of the annular fin (12) between each of the two round pillars (11) and the plate portion (1a) of the wheel body (1) to be assigned thereto forms an opening (13) as a gap (SP) for an air outlet (8).

6. The wheel brake disc (2) according to claim 1 or 2, 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 which it is assigned.

7. 3. The wheel brake disc (2) according to claim 1 or 2, characterized in that the first round pillar (10) has a contact surface (AF) for contacting 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 specific dimension in the axial direction.

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

9. 3. The wheel brake disc (2) according to claim 1 or 2, characterized in that the round pillar (10, 10a, 10b) has a conical shape with its largest diameter located on the surface of the rear face (R) of the at least two friction discs (2a, 2b).

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