Wheel-mounted brake disc for rail vehicles

Abstract

A wheel-mounted brake disc (2) comprises at least two friction discs (2a, 2b), which are arranged on both sides of a crosspiece (1a) of a wheel body (1) of a rail wheel and are fastened by means of fastening elements (4b), wherein the at least two friction discs (2a, 2b) have cooling ribs and fastening bosses (4), wherein the fastening elements (4b) extend through the fastening bosses (4) of the two friction discs (2a, 2b) and through the crosspiece (1a). The at least two friction discs (2a, 2b) have round crosspieces (10, 10a, 10b) and at least one annular rib (12) to form cooling ribs.

Description

[0001] Wheel brake disc for rail vehicles

[0002] The invention relates to a wheel brake disc for rail vehicles according to the preamble of claim 1.

[0003] Such a wheel brake disc of rail vehicles is usually attached to a wheel body of a rail wheel.

[0004] This is illustrated in Figures 1-2 in schematic partial sections of a schematic radial sectional view of a wheel body 1 with a web 1a, an axle 1b, and a wheel brake disc 2 according to the prior art. Figure 3 shows a schematic plan view of a rear side R of a friction disc 2a, 2b of the wheel brake disc 2 according to Figures 1 to 2 according to the prior art.

[0005] The wheel brake disc 2 has two friction discs 2a, 2b, each with a friction surface RF. On the rear sides R of the friction discs 2a, 2b, fastening domes 4, distributed evenly over a diameter, protrude parallel to the direction of the axis 1b, each with a respective support surface AF and a respective through-hole 4a. The two friction discs 2a, 2b are clamped together against a wheel disc or against the web 1a of the wheel body 1 by fastening elements 4b, here through-bolts, which extend through the through-holes 4a.

[0006] Rotation of the friction discs 2a, 2b on the wheel disc or on the web 1a is usually prevented by radially arranged sliding blocks (not shown) in radial grooves 19. These also absorb all forces acting on the wheel disc in the tangential direction, such as the friction force between the brake pad (not shown, but easily imagined) and the friction disc 2a, 2b, and transmit them to the wheel body 1 of the associated wheel.

[0007] The wheel brake disc 2 is provided with cooling fins 3, which increase the cooling surface in cooling channels K between the cooling fins 3 and between the cooling fins 3 and the domes 4 and, at the same time, have a high ventilation effect when the wheel brake disc 2 rotates, which generally leads to a high and effective cooling effect. The ventilation effect of the cooling fins 3 causes ventilation of the air, which is sucked into the cooling channels K through air inlets 7 at a respective inner diameter 5 of the friction discs 2a, 2b and, due to the centrifugal force caused by rotation, exits radially as air flows 7a at an outer diameter 6 of the cooling channel or the friction disc 2a, 2b through air outlets 8 as air flow 8a.

[0008] This is shown in Figure 3 together with a distribution of the cooling fins 3 and fastening domes 4 on the rear side R of the friction disc 2a, 2b. The cooling fins 3 run essentially in a radial direction from the inner diameter 5 to the outer diameter 6. In the area of ​​the fastening domes 4, the cooling fins 3 are divided into two parts by the respective fastening dome 4.

[0009] The cooling fins 3 are arranged with contact surfaces for contact with the web 1a. The mounting domes 4 are arranged at a central diameter with contact surfaces, also for contact with the web 1a.

[0010] Further examples of friction discs 2a, 2b with different cooling fins 3, 3a - 3e from the prior art are shown in Figures 4 and 5.

[0011] In Figure 4, the cooling fins 3 extend straight in the radial direction of the friction disc 2a, 2b and are not interrupted by the fastening domes 4.

[0012] Figure 5 shows cooling fins 3a - 3e, which are arranged as circular arc sections with respective different arc lengths on five coaxial circles between the inner diameter 5 and outer diameter 6 of the friction disc 2a, 2b.

[0013] Figure 6 shows a schematic perspective view of a shaft brake disc 2 according to the prior art, which has so-called round webs 9.

[0014] Figure 7 shows a partial section of the shaft brake disc 2. The round webs 9 here have a double-conical shape, the smaller diameters of which are arranged in the center of each round web 9. Air outlets 8 for the escaping air flows 8a form gaps SP and are each formed by two round webs 9 between the friction discs 2a, 2b at their outer diameters 6, with one length of the gap SP being the distance between the rear sides R of the friction discs 2a, 2b. A disadvantage is that, given the high fan power loss generated, an efficient cooling effect cannot be spoken of.

[0015] Therefore, the object of the invention is to create an improved wheel brake disc with reduced fan loss and increased cooling effect of the wheel brake disc

[0016] The problem is solved by the subject matter of claim 1.

[0017] One idea of ​​the invention is to maximize the surface area of ​​the friction disc in the cooling channel while simultaneously keeping the air conveying effect of these surface-enlarging elements low.

[0018] A wheel brake disc according to the invention comprises at least two friction discs arranged on either side of a web of a wheel body of a rail wheel and secured by means of fastening elements. The at least two friction discs have cooling fins and fastening domes, the fastening elements extending through the fastening domes of both friction discs and the web. The at least two friction discs have round webs and at least one annular rib as cooling fins.

[0019] The wheel brake disc according to the invention thus offers the advantage of a combination of design features. The ventilation of the air, which is drawn into the cooling channel at the inner diameter of the friction disc and radially exits the outer diameter of the cooling channel due to the centrifugal force caused by rotation, is throttled. At the same time, the ventilated air volume advantageously cools the friction disc, which heats up during braking.

[0020] In this way, the surface area of ​​the friction disc in the cooling channel can be maximized by means of the round webs, while at the same time the air conveying effect of these surface-enlarging elements can be kept low.

[0021] In one embodiment, the round ribs are arranged on circles with different diameters on the at least two friction discs, with the at least one annular rib being arranged as a circumferential annular rib on a circle with a diameter that lies on an outer diameter of each of the at least two friction discs. These round ribs cause a fluidic turbulence in the radially flowing air, thereby generating a very efficient thermodynamic heat transfer to the turbulent air flow thus generated, with regard to the air volume conveyed.

[0022] The annular rib was chosen for the advantageous throttling of the air flow. The annular rib also offers the additional advantage of further increasing the cooling surface in the cooling channel.

[0023] Another design provides for the at least two friction discs to have additional round webs connected by the annular rib. This is advantageous because it increases the cooling surface and also stiffens the annular rib.

[0024] The circular webs connected by the annular rib are arranged at regular angular intervals from one another, with the angular interval having an angular value that lies in a range of 3° to 15°, preferably 5° to 10°, or preferably 5°. This results in an advantageously stable structure.

[0025] In a further embodiment, the round webs connected by the annular rib can have a circular-cylindrical cross-section to enable an advantageous, simple structure. Other cross-sections are, of course, also conceivable.

[0026] In yet another embodiment, the round webs connected by the annular rib protrude further in axial length from the rear side of the friction disc than the annular rib by a certain, predefined amount. This can advantageously influence air discharge.

[0027] For this purpose, a further design provides for a section of the annular rib between each two round webs and the web of the corresponding wheel body to form an opening section that serves as a gap for air outlet. A particular advantage of this is that its primary function is to create a gap between the friction discs and the web of the rail wheel. This gap at the air outlet from the cooling channel can be made wider or narrower depending on the needs of different projects.

[0028] Further advantageous embodiments are specified in the subclaims.

[0029] In yet another embodiment, the round webs, which are connected by the annular rib, each have contact surfaces for engagement with the web of the corresponding wheel body. This results in an advantageously stable structure.

[0030] If first round webs have contact surfaces for engagement with the web of the associated wheel body, with second and third round webs being designed to be shorter than the first round webs in the axial direction by a certain amount, it is advantageous that a stable structure with air conveyance and turbulence of the air flows is possible.

[0031] In yet another embodiment, the first circular webs, which have the contact surfaces, are arranged on a first circle with a first diameter, wherein the first circle lies on an inner diameter of the respective friction disc.

[0032] In another embodiment, the round webs are conical in shape, with their largest diameter located on the surface of the rear side of at least two friction discs. This can advantageously influence the air flow and the turbulence of the air streams.

[0033] Embodiments of the invention are described below with reference to the accompanying drawings. These embodiments serve merely to illustrate the invention using preferred designs, but do not represent the invention exhaustively. Therefore, other embodiments, as well as modifications and equivalents of the illustrated embodiments, are also feasible within the scope of the claims.

[0034] They show:

[0035] Figures 1-2 show schematic partial sections of a schematic radial sectional view of a wheel body with a wheel brake disc according to the prior art; Figure 3 shows a schematic plan view of a rear side of a friction disc of the wheel brake disc according to Figures 1 to 2 according to the prior art;

[0036] Figures 4-5 show schematic top views of wheel brake discs according to the state of the art,

[0037] Figures 6-7 show schematic views of a prior art shaft brake disc;

[0038] Figures 8-9 are schematic perspective views of a rear side of a friction disc of a wheel brake disc according to the invention;

[0039] Figure 10 is a schematic partial section of a schematic radial sectional view of a wheel body with the wheel brake disc according to the invention according to Figures 8-9; and

[0040] Figure 1 1 is a schematic partial side view of the wheel brake disc according to the invention according to Figures 8-10.

[0041] Figures 1-7 have already been described above.

[0042] Figure 8 shows a schematic perspective view of a rear side R of a friction disc 2a, 2b of a wheel brake disc 2 according to the invention. Figure 9 shows an enlarged partial section of the friction disc 2a, 2b according to Figure 8. Figure 10 shows a schematic partial section of a schematic radial sectional view of a wheel body 1 with the wheel brake disc 2 according to the invention. Figure 11 shows a schematic partial side view of a friction disc 2a, 2b of the wheel brake disc 2 according to the invention according to Figures 8 to 10.

[0043] The friction disc 2a, 2b in Figure 8 is divided radially into four circles with diameters 14, 15, 16, 17 for better clarity and delimited by the inner diameter 5 and outer diameter 6. The smallest diameter is the inner diameter 5 and then the four diameters 14, 15, 16, 17 follow in ascending order up to the outer diameter 6. The first circle with the first diameter 14 is located at the inner diameter 5. Circular sectors 20, 20a are distributed over the friction disc 2a, 2b, of which only two are shown here as examples. Each circular sector 20, 20a is defined by two imaginary radial dividing lines. On each dividing line there is a fastening dome 4 from a number of twelve fastening domes 4, which is shown here as an example. The angle between two dividing lines of each circular sector 20, 20a is 30°. The circular sectors 20, 20a differ firstly in that in the circular sectors 20a radial grooves 19 are arranged between the 4.

[0044] The fastening domes 4 are arranged at equal angular distances from one another on a diameter 18, which is approximately a mean diameter of the friction disc 2a, 2b.

[0045] For the design of the surface-enlarging elements in the cooling channels K (see Figure 9), so-called round webs 10, 10a, 10b are selected here.

[0046] These circular webs 10, 10a, 10b cause the radially flowing air to swirl, resulting in a very efficient thermodynamic heat transfer to the air, considering the air volume conveyed. In other words, a turbulent air flow is created whose heat transfer is higher than with laminar air flow.

[0047] The circular webs 10, 10a, 10b are attached or molded onto the circles with different diameters 14, 15, 16, 17 on the rear side R of the friction disc 2a, 2b. They protrude in the axial direction from the rear side R of the friction disc 2a, 2b.

[0048] First round webs 10 are arranged on the first diameter 14, second round webs 10a on the second diameter 15 and third round webs 10b on the third diameter 16.

[0049] The first circular webs 10 are arranged on the first diameter 14 in the circular sectors 20 in groups of three and in the circular sectors 20a in groups of two.

[0050] The second round webs 10a are present in the second diameter 15 only in the circular sectors 20 between two fastening domes 4. And on the third diameter 16, the third round webs 10b are arranged in groups of three in the circular sectors 20 and in groups of two in the circular sectors 20a.

[0051] The round webs 10, 10a, 10b have a conical shape, with their largest diameter located on the surface of the rear side R. The axial lengths of the round webs 10, 10a, 10b vary here. Thus, the first round webs 10 have contact surfaces AF with which they rest against the web 1a of the wheel body 1. The second and third round webs 10a, 10b are shorter than these and have a distance between their upper surfaces and the web 1a. This can be seen in Figure 11.

[0052] To throttle the amount of air delivered, an annular rib 12 was selected, which is arranged circumferentially on the fourth diameter 17 close to the outer diameter 6 of the friction disc 2a, 2b.

[0053] The annular rib 12 has an outer side 12a, which faces the outer diameter 6, and an inner side 12b. The annular rib 12 connects a number of round webs 11, which have a circular-cylindrical cross-section. In the example shown, there are sixty-six round webs 11, with one round web 11 being omitted in each of the circular sectors 20a due to the radial groove. The round webs 11 are arranged at regular angular intervals from one another. In this example, the angular distance between the round webs is 5°. The angular distance can have an angular value that lies in a range of, for example, 3° to 15°, preferably 5° to 10°.

[0054] The round webs 11 protrude further in axial length from the rear side R of the friction disc 2a, 2b than the annular rib 12 by a certain, predetermined amount and each have contact surfaces AF for engagement with the web 1a. In this way, each section of the annular rib 12 forms an opening section 13 between each two round webs 11 and the web 1a.

[0055] This annular rib 12 in turn also causes a further enlargement of the cooling surface in the cooling channels K, the main function being the formation of a gap SP between the friction discs 2a, 2b and the web 1a of the wheel body 1. This gap SP is clearly visible in Figure 10. The gap SP is the distance between the opening section 13 of the annular rib 12 between two round webs 11 at the air outlet 8 from the cooling channel K and can be made wider or narrower depending on the needs of different applications.

[0056] 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 against the annular rib 12 and is deflected axially upwards over the annular rib 12 through the opening section 13 as air flow 8a into the air outlet 8. On the other hand, the air flow 7a is split tangentially to the left and right into further air flows 8b upon impact with the inner side 12b of the annular rib 12.

[0057] Thus, the wheel brake disc 2 has a low fan loss due to air ventilation in the area of ​​the cooling channel K between the friction disc 2a, 2b and the wheel body 1 with the highest possible cooling effect of the friction disc 2a, 2b.

[0058] The invention is not limited by the embodiment given above, but can be modified within the scope of the claims.

[0059] List of reference symbols

[0060] 1 wheel body

[0061] 1 a footbridge

[0062] 1 b axis

[0063] 2 wheel brake discs

[0064] 2a, 2b friction disc

[0065] 3, 3a, 3b, 3c, 3d, 3e cooling fin

[0066] 4 Mounting dome

[0067] 4a Through hole

[0068] 4b Fastening element

[0069] 5 inner diameter

[0070] 6 outer diameter

[0071] 7 Air inlet

[0072] 7a Air flow

[0073] 8 Air outlet

[0074] 8a, 8b Air flow

[0075] 9; 10, 10a, 10b; 1 1 round bridge

[0076] 1 1 a top

[0077] 12 ring ribs

[0078] 12a Outside

[0079] 12b Inside

[0080] 13 Opening section

[0081] 14, 15, 16, 17, 18 diameter

[0082] 19 Radial groove

[0083] 20, 20a circular sector

[0084] AF support surface

[0085] K Cooling channel

[0086] R back

[0087] RF friction surface

[0088] SP Spalt

Claims

Claims 1. Wheel brake disc (2) comprising at least two friction discs (2a, 2b) arranged on both sides of a web (1a) of a wheel body (1) of a rail wheel and fastened by means of fastening elements (4b), wherein the at least two friction discs (2a, 2b) have cooling fins and mounting bosses (4), wherein the fastening elements (4b) extend through the mounting bosses (4) of both friction discs (2a, 2b) and the web (1a), characterized in that the at least two friction discs (2a, 2b) have round webs (10, 10a, 10b) and at least one annular rib (12) as cooling fins.

2. Wheel brake disc (2) according to claim 1 , characterized in that the round webs (10, 10a, 10b) are arranged on circles with different diameters (14, 15, 16) on the at least two friction discs (2a, 2b), wherein the at least one annular rib (12) is arranged as a circumferential annular rib (12) on a circle with a diameter (17) which lies on an 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 webs (1 1 ) which are connected by the ring rib (12).

4. Wheel brake disc (2) according to claim 3, characterized in that the round webs (1 1 ) connected by the ring rib (12) are arranged at regular angular intervals to each other, wherein the angular interval has an angular value which is in a range of 3° to 15°, preferably 5° to 10° or preferably 5°.

5. Wheel brake disc (2) according to claim 3 or 4, characterized in that the round webs (1 1 ) connected by the ring rib (12) have a circular cylindrical cross-section.

6. Wheel brake disc (2) according to one of claims 3 to 5, characterized in that the round webs (11) connected by the ring rib are in axial length protrudes further from a rear side (R) of the friction disc (2a, 2b) than the ring rib (12) to a certain, predetermined extent.

7. Wheel brake disc (2) according to claim 6, characterized in that a respective section of the ring rib (12) between each of two round webs (11 ) and the web (1 a) of the associated wheel body (1 ) forms an opening section (13) as a gap (SP) for an air outlet (8).

8. Wheel brake disc (2) according to one of claims 3 to 7, characterized in that the round webs (11) which are connected by the ring rib (12) each have bearing surfaces (AF) for contact with the web (1 a) of the associated wheel body (1 ).

9. Wheel brake disc (2) according to one of the preceding claims, characterized in that first round webs (10) have bearing surfaces (AF) for contact with the web (1 a) of the associated wheel body (1 ), wherein second and third round webs (10a, 10b) are designed to be shorter in the axial direction by a certain amount than the first round webs (10).

10. Wheel brake disc (2) according to claim 7, characterized in that the first round webs (10) which have the bearing surfaces (AF) are arranged on a first circle with a first diameter (14), wherein the first circle is located at an inner diameter (5) of the respective friction disc (2a, 2b).

11. Wheel brake disc (2) according to one of the preceding claims, characterized in that the round webs (10, 10a, 10b) have a conical shape, the largest diameter of which is located on the surface of the back (R) of the at least two friction discs (2a, 2b).

Images