Braking resistor and vehicle equipped with same

Abstract

The invention relates to a braking resistor for a vehicle equipped with an electrodynamic braking device, wherein the braking resistor has a plurality of elongate, cylindrical heating cartridges (1) that are supported parallel to one another on at least one floating bearing support (9), wherein the heating cartridges (1) are held by means of a bearing arrangement comprising floating bearings which are fastened to the floating bearing support (9).

Description

[0001] Description

[0002] Braking resistor and vehicle equipped with it

[0003] The invention relates to a braking resistor for a vehicle equipped with an electrodynamic braking device, in particular a rail vehicle, and to a vehicle equipped with such a braking resistor.

[0004] A well-known braking resistor is described, for example, in DE 10 2017 207 274 B3. The braking resistor described therein is installed on a rail vehicle, located in its roof area, and is constantly exposed to airflow to cool it. The reason for this is that, during braking, the braking resistor is supplied with current from the vehicle's electrodynamic brake. This current heats up the braking resistor, necessitating subsequent cooling.

[0005] When cooling is achieved through airflow, a problem arises: not all surfaces of the brake resistor are cooled to the same extent, as some surface areas are more easily accessible to the cooling airflow than others. This can lead to thermally induced deformations / movements of the brake resistor.

[0006] Based on this, the invention aims to further develop the braking resistor of the type mentioned above in such a way that it can be used safely even under thermal conditions that vary across the braking resistor.

[0007] This problem is solved by a braking resistor having the features of claim 1 and by a vehicle according to claim 7.

[0008] The problem is solved with regard to the braking resistance by the fact that the braking resistance has a plurality of elongated, cylindrical heating cartridges supported parallel to each other on at least one floating bearing carrier, wherein the heating cartridges are held by means of a bearing arrangement that includes floating bearings which are attached to the floating bearing carrier.

[0009] The use of floating bearings for mounting the heating cartridges allows for any thermal expansion of the heating cartridges to be accommodated. In particular, it is possible to mount the majority of the heating cartridges at a suitable point in the transverse direction of their longitudinal extent using a suitable fixed bearing, while sections of the heating cartridges farther from the fixed bearing are held in position in the transverse direction of the heating cartridges by means of the floating bearings presented here.

[0010] The heating cartridges can, in particular, have an outer metal casing filled with a compacted ceramic powder and a heating wire running along the length of the cartridge within the ceramic powder, with electrical connections for the heating wire being provided at each end of the heating cartridge. This results in a heating cartridge with which a braking resistor can be easily constructed, requiring a sufficient number of heating cartridges to meet the requirements of the braking resistor.

[0011] Each loose bearing can have a loose bearing retaining bracket attached to a loose bearing support section, with each loose bearing support section running along one of the heating cartridges. A "loose bearing support section" is understood to be a preferably strip-shaped section of the loose bearing support to which the associated loose bearing retaining bracket is attached, possibly with an insulating plate in between.

[0012] Advantageously, the floating bearing retaining lugs each consist of an elastic clip-in section associated with a heating cartridge and a fastening section adjoining the clip-in section, with the fastening section being attached to the floating bearing carrier. Due to the elasticity of the clip-in section, it is possible to hold heating cartridges of varying diameters using the same floating bearings. Furthermore, it is possible for the heating cartridges to undergo a sliding movement relative to the retaining lug and the floating bearing carrier in their longitudinal direction due to thermal expansion within the clip-in section.

[0013] The retaining clips for the floating bearings are preferably manufactured from a strip-shaped bent sheet metal part (for large quantities from slit strip (narrow sheet coils), for smaller quantities from sheet metal) by forming, wherein the clip-in section has a substantially circular segment-shaped cross-section and is open on its side opposite the mounting section to accommodate a heating cartridge. The mounting section adjoins the clip-in section, and a flat side of the mounting section opposite the clip-in section can be placed onto the floating bearing support section. After suitable positioning of the retaining clips, they can be firmly connected to their associated floating bearing support sections, for example by riveting.

[0014] It is advantageous if loose bearings assigned to immediately adjacent heating cartridges are arranged offset from each other along the heating cartridges. This allows for a space-saving arrangement of the heating cartridge as a whole.

[0015] The problem stated above is solved with respect to the vehicle by a vehicle equipped with an electrodynamic braking device and a braking resistor of the type described above. The vehicle can, in particular, be a rail vehicle, in which case the braking resistor can typically be located on the vehicle roof. An embodiment of the invention is explained in more detail below with reference to the drawing. The drawing shows:

[0016] Figure 1 shows a side view of a heating cartridge for use with a braking resistor.

[0017] Figure 2 is a cross-sectional view of the heating cartridge from Figure

[0018] 1,

[0019] Figure 3 shows a side view of a storage arrangement for heating cartridges according to Figure 1.

[0020] Figure 4 shows a perspective view of a loose bearing retaining tab of the bearing arrangement shown in Figure 3.

[0021] Figure 5 shows a schematic top view of the bearing arrangement of Figure 3 with built-in heating cartridges,

[0022] Figure 6 shows a perspective view of a brake resistor, equipped with heating cartridges according to Figure 1, with the cover removed.

[0023] A key element of the braking resistor described here for a vehicle equipped with an electrodynamic braking system, particularly a rail vehicle, is shown in Figures 1 and 2. This element is a heating cartridge 1, which has an elongated, cylindrical or rod-shaped outer form. The heating cartridge 1 is equipped with electrical connections 2 at each of its two end faces. As can be seen in Figure 2, the heating cartridge 1 has an outer metal casing 3, which is filled with a highly compressed ceramic powder 4 and a high-temperature resistant heating wire 5, the heating wire 5 being centrally located within the heating cartridge 1.

[0024] A plurality of parallel heating cartridges 1 form a braking resistor. During braking, the heating cartridges 1 are energized by current from the vehicle's electrodynamic brake. This electric current causes the heating cartridges 1 to heat up. Simultaneously, the heating cartridges 1 are cooled by the airflow. Since heat dissipation is greater at the surface of the heating cartridge 1 directly exposed to the airflow than at other surfaces, this surface cools down more rapidly, and the temperature varies between the top and bottom of the cartridge. Due to the different thermal expansion of the heating cartridge surfaces, there is a risk of deformation (bending) or twisting.

[0025] Figure 3 shows a section of a bearing arrangement for heating cartridges identical in construction to the heating cartridge 1. It is evident that retaining tabs 6 are provided to create floating bearings for the heating cartridges 1. These retaining tabs are attached to associated floating bearing support sections 8 by means of rivets 7. The floating bearing retaining tabs 6 rest on the floating bearing support sections 8 with insulating plates 15 in between. These support sections are in turn supported on a floating bearing support 9 extending transversely to the heating cartridges 1. The rivets 7 extend through both the top surface of the floating bearing support and through the respective associated floating bearing support sections 8.

[0026] The rail-shaped or U-shaped sliding bearing support 9 is rigidly clamped between two support beams 10 located laterally to the braking resistor (see Figure 6). The support beams 10 extend parallel to the heating cartridges 1.

[0027] Figure 4 shows the external shape of a retaining tab 6 in more detail. An upper clip-in section 11 of the retaining tab 6, associated with the heating cartridge 1, has a circular segment-shaped cross-section, with the free ends of the clip-in section 11 curved outwards to facilitate insertion of the heating cartridge 1 into the clip-in section 11. A lower fastening section 12 of the retaining tab 6 has a flat side facing the associated floating bearing support section 8 with two through holes 13 to allow the retaining tab 6 to be fastened by means of rivets.

[0028] The retaining tab 6 is made from an elastic, formed, strip-shaped sheet metal part and can therefore be designed with thin walls. Due to the elasticity of the retaining tab 6, it is possible to securely hold heating cartridges of different diameters using the same clip section 11.

[0029] Figure 5 shows that the heating cartridges 1 are mounted close together, with the retaining tabs 6 being offset from each other in the longitudinal direction of the heating cartridges 1 when the heating cartridges 1 are directly adjacent to each other. In the embodiment shown in Figure 5, there are two offset rows of retaining tabs 6 for a given loose bearing 2 in the longitudinal direction of the heating cartridges 1.

[0030] Figure 6 illustrates a possible overall design of the single-layer braking resistor. In Figure 6, the braking resistor is mounted on the roof of a rail vehicle, with the fairing omitted. The mounting for the heating cartridges 1 comprises a centrally located fixed bearing 14 and, in the illustrated embodiment, six floating bearings, the position of which can be determined from the position of the floating bearing supports 9 (the dimensions of the retaining lugs 6 are too small to be shown in Figure 6). The six floating bearings ensure that all heating cartridges 1 are held loosely at multiple points. This is intended to prevent excessive deformation and vibration of the heating cartridges 1. Due to the thin walls of the retaining lugs 6, they have low flow resistance. They also serve to dissipate heat generated when current flows through the heating cartridges 1.Under thermal stress, the central sections of the heating cartridges 1 retain their position in the area of ​​the fixed bearing 14, while sections of the heating cartridges 1 located further away from it are movable in the clip-in sections 11 of the retaining tabs 6.

Claims

Patent claims 1. Braking resistor for a vehicle equipped with an electrodynamic braking device, characterized in that the braking resistor has a plurality of elongated, cylindrical heating cartridges (1) supported parallel to each other on at least one floating bearing carrier (9), wherein the heating cartridges (1) are held by means of a bearing arrangement comprising floating bearings which are attached to the floating bearing carrier (9).

2. Braking resistor according to claim 1, characterized in that the heating cartridges (1) have an outer metal jacket (3) which is filled with a compacted ceramic powder (4) and a heating wire (5) extending within the ceramic powder (4) along the associated heating cartridge (1), wherein electrical connections (2) for the heating wire (1) are provided at the ends of the heating cartridges (1).

3. Braking resistor according to claim 1 or 2, characterized in that the floating bearings each have a floating bearing retaining tab (6) which is attached to a floating bearing support section (8), wherein the floating bearing support sections (8) each run along one of the heating cartridges (1).

4. Braking resistor according to claim 3, characterized in that the loose bearing retaining tabs (6) each have an elastic clip-in section (11) associated with the heating cartridge (1) and a fastening section (12) adjoining the clip-in section (11), which is attached to the loose bearing support section (8).

5. Braking resistor according to one of claims 1 to 4, characterized in that the loose bearing retaining tabs (6) are each made from a strip-shaped sheet metal bent part by forming, wherein the clip-in section (11) has a substantially circular segment-shaped cross-section and is open on its side opposite the fastening section (12) for receiving a heating cartridge.

6. Braking resistor according to one of claims 1 to 5, characterized in that Loose bearings, which are assigned to immediately adjacent heating cartridges (1), are arranged offset from each other along the heating cartridges (1).

7. Vehicle with an electrodynamic braking device and a braking resistor according to one of claims 1 to 6.

8. Vehicle according to claim 7, designed as a rail vehicle.

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