Cover flap for a filling connection of a rail vehicle having a plug for insertion into the filling connection

The spring-loaded plug and cap system for rail vehicle drinking water systems securely seals the filling connection, addressing contamination issues and ensuring compliance with hygiene standards, enabling automated filling and reducing maintenance needs.

WO2026068199A1PCT designated stage Publication Date: 2026-04-02SIEMENS MOBILITY GMBH
View PDF 7 Cites 0 Cited by

Patent Information

Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Filing Date
2025-09-11
Publication Date
2026-04-02

AI Technical Summary

Technical Problem

Existing flap devices for rail vehicle drinking water systems fail to securely seal the filling connection against contaminants and dust under dynamic pressure conditions, leading to potential water quality issues and non-compliance with hygiene standards.

Method used

A spring-loaded, frustoconical plug integrated with a flap device that is permanently attached to the rail vehicle, ensuring secure sealing and tamper-proof coverage of the filling connection, with a cap and drainage system to prevent ingress of foreign particles and allow fluid drainage.

Benefits of technology

The solution provides a hygienic, tamper-proof seal that prevents contamination during dynamic conditions, maintains water quality, and ensures compliance with standards, facilitating automated filling without loose parts and additional handling.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure EP2025075832_02042026_PF_FP_ABST
    Figure EP2025075832_02042026_PF_FP_ABST
Patent Text Reader

Abstract

The invention relates to: a flap device (1) comprising a flap (2) for covering a filling connection (5) of a drinking-water system of a rail vehicle (11); and a rail vehicle (11) comprising such a flap device (1), wherein the flap device (1) comprises a frustoconical plug (3) which is arranged on an inner side (6) of the flap and can be moved relative to the flap (2) with deformation of a spring (4).
Need to check novelty before this filing date? Find Prior Art

Description

[0001] 202416991

[0002] 1

[0003] Description

[0004] Cover flap for a filling port of a rail vehicle with a plug for insertion into the filling port

[0005] Technical field

[0006] The invention relates to a flap device with a flap for covering a filling connection of a drinking water system of a rail vehicle and to a rail vehicle with such a flap device.

[0007] Technical background

[0008] Drinking water can be provided on passenger rail vehicles. To achieve this, the requirements for drinking water hygiene must be adequately met during delivery, transport, storage, and distribution of the water. To prevent or inhibit any unacceptable changes in water quality, contaminants and germs that have entered the supply chain must be removed, requiring technical and financial resources.

[0009] In addition to the natural growth of organisms present in the water and the colonization of tank and piping surfaces (biofilm), subsequently introduced particles containing microorganisms also affect the hygiene status of a drinking water system. This subsequent introduction can be facilitated by venting the tank system during operation, by dynamic pressure fluctuations, e.g., when traveling through tunnels, or by permanent pressure differences, e.g., due to crosswinds. A higher level of particle ingress is to be expected under particularly sandy or dusty environmental conditions than in clear air. In any case, it is advantageous to impede the introduction of unwanted or contaminated particles into the tank system through appropriate measures, thereby extending the maintenance of drinking water quality.

[0010] The standard DIN EN 16362:2013, applicable to railway vehicle technology, stipulates that water inlet openings, also known as filler necks, must be protected by suitable covers to prevent the ingress of dirt particles and snow. The standard requires that the cover must extend at least 12 mm around the water inlet opening. Furthermore, the standard stipulates that overflow and dripping water must be able to drain away to prevent freezing of water in the pipes and other issues. 202416991

[0011] 2

[0012] To avoid the inability to fill the system due to frozen pipes.

[0013] The standard specifically illustrates a cover device; this consists of a flap that, for ferry operation of the rail vehicle, is hinged in front of the pipe opening, thus covering it. If the rail vehicle is to be filled with a fluid, such as drinking water, the flap is swung open, thereby exposing the pipe opening and allowing the connection of an external filling line.

[0014] The flap devices used are technically simple solutions for covering the filling connections of drinking water systems in rail vehicles to prevent the ingress of dirt. However, under uneven airflow and at higher speeds, these devices no longer close securely, and contaminated dirt or dust particles can still enter.

[0015] Such flap devices are known, for example, from the publications DD 2 84 197 A5 or WO 2017 / 055008 A1.

[0016] From the prior art according to DE 10 2016 202 078 A1, a loose cap is known that is placed on the open end of a drinking water pipe – the filling connection – and is attached to the filling connection, for example, by means of a bayonet fitting. The cap also has a plug that is inserted into the filling connection. In practice, however, the loose caps equipped with plugs are regularly lost or are not replaced after the filling process, so that the filling connection is unprotected and exposed to the environment.

[0017] Summary of the invention

[0018] The invention is based on the objective of providing a covering device for covering a filling connection of a drinking water system of a rail vehicle, which overcomes the disadvantages of the prior art.

[0019] The problem is solved by the subject matter of independent claim 1. Further developments and embodiments of the invention are found in the features of the dependent claims. 202416991

[0020] 3

[0021] The flap device according to the invention provides a hygienic and tamper-proof cover for the drinking water filling connection of the rail vehicle. All parts are securely attached to a flap. No additional handling is required before, during, or after filling. Furthermore, the flap device cannot be lost, as it is permanently attached to the rail vehicle.

[0022] After filling, the flap can simply be closed. A spring-loaded plug on the flap centers itself and aligns axially when inserted into the open end of the filling connection, thus sealing it. This prevents the ingress of snow, brake dust, dust, and sand during dynamic pressure differences between the drinking water tank and the filling connection. Even under static pressure differences, such as those caused by crosswinds or sandstorms, the transport of particles into the rail vehicle's drinking water system through the filling connection is significantly reduced.

[0023] Opening the flap moves all components to the side. Access to the filling port remains unobstructed. The filling process can be started without restriction or additional handling.

[0024] Embodiments of the invention

[0025] A flap device according to the invention for a rail vehicle for covering a filling connection of the rail vehicle, in particular for drinking water, comprises a flap and a frustoconical plug, wherein the frustoconical plug is arranged on an inner side of the flap and is movable against the flap by deformation of at least one spring. The frustoconical plug is arranged on the inner side of the flap, in particular by means of spring mounting. The plug is arranged on the inner side of the flap such that a base surface of the frustoconical plug faces the inner side of the flap. Correspondingly, its opposite, tapered end, in particular a top surface of the frustoconical plug, faces away from the inner side of the flap. The filling connection is in particular part of a drinking water system of the rail vehicle.

[0026] A rail vehicle according to the invention, in particular a passenger rail vehicle, comprises at least one drinking water system with at least one filling connection and at least one flap device according to the invention for covering the filling connection, wherein the flap of the flap device is hinged to the rail vehicle. The drinking water system of the rail vehicle comprises in particular at least one drinking water tank and at least one or more 202416991

[0027] 4

[0028] Drinking water lines. The filling connection can be designed as an opening at one end of a drinking water line in the rail vehicle, i.e., as an open end of a drinking water line. It serves to fill the drinking water system of the rail vehicle with drinking water and can also be referred to as a filling nozzle, drinking water connection, or drinking water filling connection. The filling connection is advantageously designed to be at least partially complementary to the frustoconical plug. The filling connection can be funnel-shaped, particularly in the area of ​​an open end. It can have an inner conical surface complementary to a surface of the frustoconical plug.

[0029] The flap is positioned on the rail vehicle, particularly in an area in front of the filling port, such that it covers the filling port when folded down and exposes it when folded up. In the folded-up, open position of the flap, the filling port is thus accessible from the outside.

[0030] The flap device is designed and arranged on the rail vehicle such that, in the closed position of the flap, the plug is at least partially inserted into the filling port, and in the open position, the plug exposes the filling port, particularly for filling the drinking water system with drinking water. The plug is designed for insertion into the filling port. When at least partially inserted into the filling port, it at least partially seals it.

[0031] The plug is further developed to be at least partially, and in particular at least section by section, complementary to the filling port. This reliably prevents the ingress of foreign objects into the filling port when the flap is closed. The shape and size of the plug, in particular the outer diameter of its surface, and of the filling port, in particular its inner cross-section, can be coordinated and dimensioned accordingly. They can be designed to fit each other precisely, at least in section. The surface of the plug can, at least in section, after the plug is inserted into the filling port, form a positive fit, in particular a sealing one, against a complementary inner conical surface of the filling port.

[0032] According to a further embodiment of the invention, the flap device has at least one hinge element for forming a hinge with a further, in particular complementary, hinge element of the rail vehicle. For better distinction, the at least one hinge element of the flap device is referred to below as the first hinge element and the at least one further hinge element of the rail vehicle as 202416991.

[0033] 5. The second hinge element is designated. The first hinge element of the flap device is arranged on the flap, in particular on an inner side of the flap, and is connectable to the second hinge element of the rail vehicle in order to attach the flap to the rail vehicle in a hingeable manner by means of the first hinge element.

[0034] Accordingly, the rail vehicle, in its further developed form, has at least one further, second hinge element for forming a hinge with the at least one first hinge element of the flap, wherein the further, second hinge element of the rail vehicle is arranged on the rail vehicle, in particular in the area of ​​the filling connection, and is connected to the at least one first hinge element of the flap in a manner that forms the hinge, so that the flap is hinged to the rail vehicle. The at least one further, second hinge element of the rail vehicle is in particular designed to be complementary to the at least one first hinge element of the flap.

[0035] The flap of the flap device is advantageously arranged on and connected to the at least one complementary second hinge element of the rail vehicle by means of its at least one first hinge element. The at least one second hinge element of the rail vehicle interacts with the at least one first hinge element of the flap in such a way that at least one hinge is formed about which the flap can be folded towards the rail vehicle.

[0036] Advantageously, the rail vehicle with the flap device according to the invention is designed in such a way that the flap, in particular an outer side of the flap, is flush with an outer skin of the rail vehicle in the folded, closed position of the flap.

[0037] In a further development, the plug can have at least one drainage groove in a lateral surface of the frustoconical plug. The at least one drainage groove is provided, in particular, at least at the edge of the conical lateral surface, or cone surface, of the frustoconical plug. In such a design, the at least one drainage groove forms a fluid channel bounded by the lateral surface of the frustoconical plug and the complementary inner conical surface of the filling connection. The plug can be designed according to the plug element of DE 10 2016 202 078 A1, to which reference is made here. The plug can be provided with a plurality of drainage grooves. The drainage grooves are preferably arranged rotationally symmetrically. They serve to drain away dripping water. 202416991

[0038] 6

[0039] The plug can be made of plastic. It is advantageous for the plug to be made of a plastic, e.g., EPDM plastic.

[0040] According to a further embodiment of the invention, the flap device has a cap which is arranged on the inside of the flap, wherein the plug is at least partially arranged in the cap.

[0041] The cap preferably comprises a cap base, which may be formed by the inside of the flap, and an annular cap side wall. The cap side wall may adjoin the inside of the flap or be formed from it. The frustoconical plug is preferably connected to the flap with its base facing the cap base, particularly centrally within the cap, and is at least partially surrounded by the circumferential cap side wall. At least the base of the plug is positioned within the cap, at least when the flap is folded down and closed, and is thus radially enclosed by the cap side wall.

[0042] When the flap device is mounted on the rail vehicle and the flap is folded down, the cap is open towards the interior of the rail vehicle. Advantageously, the cap can be designed to partially surround the filling port, at least when the flap is folded down. The filling port is thus at least partially enclosed within the cap, and the side wall of the cap extends beyond the filling port, at least in sections, when the flap is folded down. This creates a labyrinth that prevents the ingress of dust, dirt particles, or other foreign matter.

[0043] For particularly good protection against dirt particles, it is considered advantageous if the cap base is larger than the cross-sectional area of ​​an open end of the filling port and the open end of the filling port is completely covered by the cap base. The circumferential cap sidewall is preferably arranged coaxially with the filling port and surrounds the filling port from the outside. An annular gap may exist in the radial direction between the open end of the filling port and / or between the plug and the outer cap area, in particular the cap sidewall.

[0044] The cap additionally covers the filling port on the outside and diverts any potential fluid flow through the drain groove of the stopper. 202416991

[0045] 7

[0046] Furthermore, according to a further development, at least one drainage opening can be arranged in the cap's side wall. This lateral drainage opening allows the deflected fluid flow to flow laterally outwards.

[0047] With a view to good protection of the filling port against ingress of dirt particles, it is considered advantageous if the cap completely covers the filling port to the outside and deflects a fluid flow through the drain groove of the plug into a cap area that is radially outside the open end of the filling port, and the drain opening is arranged in an area radially outside the open end of the filling port.

[0048] Regarding the arrangement of the drain opening, it is considered advantageous if a drain channel formed by the drain opening is arranged perpendicular to the longitudinal direction of the plug and / or the longitudinal direction of the drain channel lies in the plane of the open end of the filling connection or in a plane parallel to it.

[0049] One advantage is that the plug, in conjunction with the cap, can reliably prevent dirt from entering the filling port, while the drainage groove provided on the edge of the plug, in combination with the lateral drainage opening in the cap, still allows the desired drainage of fluid from the filling port.

[0050] The cap can be designed in accordance with the cap of DE 10 2016 202 078 A1, which is referenced here.

[0051] The cap may contain and / or consist of a metal or metal alloy. Additionally or alternatively, the cap may contain or consist of a plastic, such as PA or PE plastic.

[0052] According to a further development, the spring is designed to absorb compressive forces and is positioned between the plug and the inside of the flap. The spring can thus be pre-tensioned against the flap by deforming it. The plug can move against the flap in the opposite direction of the spring tension. When the flap is closed, the spring is pre-tensioned against the flap by the plug, which is at least partially inserted into the filling port. It presses the plug into the filling port with a predetermined force. When the flap is opened, the spring relaxes, and in the open, unfolded position of the flap, it is in a tension-free resting position.

[0053] It is advantageous to have a predefined spring constant, particularly for designing a check valve. The spring constant can be matched to the 202416991

[0054] 8

[0055] The dimensions of the flap mechanism and the rail vehicle, in particular the distance between the inside of the flap when closed and the filling port, and / or the dimensions of the plug and the filling port, are specified so that the plug is pressed into the filling port with a predetermined force, exerted by the pre-tensioned spring in the closed position of the flap, thus acting as a check valve. Water can therefore escape from the filling port at a predetermined water pressure, as the plug retracts at that pressure due to the spring yielding. Conversely, the filling port is sealed against the ingress of fluid or foreign matter from the outside.

[0056] The flap device can include a locking element for securing the flap in a closed position on the rail vehicle. The rail vehicle further features a complementary locking element, for example, a stop, for the flap's locking element. The flap's locking element interacts with the rail vehicle's locking element to form a lock. The flap's locking element and / or the rail vehicle's locking element can be lockable to form a lock or closure. This allows the flap to be secured not only against unintentional opening at higher speeds of the rail vehicle or during pressure fluctuations, but also to grant access to the filling port only to service personnel and block access for unauthorized persons.

[0057] Regardless of the grammatical gender of a particular term, persons with male, female or other gender identities are included.

[0058] The invention allows for numerous embodiments. It is explained in more detail with reference to the following figures, each of which illustrates an exemplary embodiment. Identical elements in the figures are designated with the same reference numerals.

[0059] Exemplary embodiments of the drawing

[0060] Fig. 1 schematically shows an exploded view of an embodiment example of a flap device according to the invention in a three-dimensional view,

[0061] Fig. 2 schematically shows an exploded view of the flap device from Fig. 1 in side view, 202416991

[0062] 9

[0063] Fig. 3 schematically shows a section of an embodiment example of a rail vehicle according to the invention with a flap device with an open flap in a three-dimensional view,

[0064] Fig. 4 schematically shows a filling connection of a rail vehicle according to the invention with a flap device with a closed flap in side view.

[0065] Detailed description of the exemplary implementations

[0066] In Fig. 1 and Fig. 2, an embodiment of a flap device 1 according to the invention is shown schematically in individual parts.

[0067] The flap assembly 1 comprises a flap 2. A first hinge element 9 is arranged on an inner surface 6 of the flap 2, by means of which the flap 2 can be hinged to a rail vehicle. A locking element 17, here a simple rotary latch lock, is also arranged on the inner surface 6 of the flap 2, with which the flap 2 can be secured in a closed position on the rail vehicle.

[0068] Furthermore, the flap assembly 1 includes a cap 8 on the inner surface 6 of the flap 2. A base surface of the cap 8, a so-called cap base 18, is formed here by the inner surface 6 of the flap 2. An annular cap side wall 19 adjoins the cap base 18 directly.

[0069] Furthermore, a guide pin 16 is centrally located in the cap 8 of the flap 2, on the cap base 18 and thus on the inner side 6 of the flap 2. It serves to guide an axial movement of a plug 3 along the guide pin 16. The plug 3 is frustoconical in shape and is guided over the guide pin 16.

[0070] A spring 4 for absorbing compressive forces is arranged between the plug 3 and the inner surface 6 of the flap 2. Here, the spring 4 is designed as a helical spring and guided over the guide pin 16. The spring 4 acts as a compression spring.

[0071] A screw 20 is connected to the guide pin 16, and its screw head forms a stop for the movable plug 3, preventing the plug 3 from moving away from the inside 6 of the flap 2. A preload on the spring 4 could be achieved via the screw 20.

[0072] The plug 3 is movable against the flap 2 by deforming the spring 4. The spring 4 can act as a stop for the movement of the plug 3 towards the inside 6 of the flap 2, 202416991

[0073] 10 when their coils are in contact with each other. Alternatively, the inner surface 6 of the flap 2 itself can limit the movement of the plug 3 to the inner surface 6 of the flap 2 as soon as its base is in contact with the inner surface 6 of the flap 2.

[0074] The plug 3 can have drainage grooves 10 on its outer surface to drain away dripping or condensed water.

[0075] Advantages of the invention include a flap device 1 permanently installed on the rail vehicle 11, which has a spring-loaded plug 3 permanently connected to the flap 2 for use in a filling port 5 of the rail vehicle 11. Thus, the plug 3, which is particularly frustoconical, can compensate for tolerances and can be securely inserted into the filling port 5, which is particularly funnel-shaped, and seals it securely against the ingress of foreign particles. Furthermore, it provides the effect of a check valve and cannot be lost. The invention also facilitates automated filling by a robot. No additional manual steps are required when using the plug 3, resulting in reduced working time and greater acceptance among service personnel.

[0076] Figure 3 illustrates an embodiment of a flap device 1 mounted on a rail vehicle 11 in the open, unfolded position of the flap 2. With the described design of the invention, when the flap 2 is open during UIC refueling (= refueling to overflow and water exiting on the opposite side), the entire cross-section of the filling port 5 is exposed. The flap 2 can be held in the open, unfolded position by means of a suitably designed flap holder, here designed as a hinged fitting 14. When the flap 2 is closed, a locking element 17 of the flap 2 can interact with a complementary locking element 21, here a stop, on the rail vehicle 11 to secure the flap 2 in the closed position, even at high speeds of the rail vehicle 11 or in the presence of pressure differences, e.g., when passing through tunnels.

[0077] Fig. 4 shows a section of an embodiment of a flap device 1 in the closed, folded-down position on a rail vehicle. The frustoconical, spring-loaded plug 3 is inserted into a funnel-shaped open end 15 of the filling port 5 of a drinking water system of the rail vehicle. The compression spring 9 is pre-tensioned by the closed flap 2. This causes the plug 3 to seal the filling port 5 tightly against the ingress of foreign particles. The annular side wall 19 of the cap 8 on the inner side 6 of the flap 2 surrounds the open end 15 of the filling port 5 and forms, in conjunction with 202416991

[0078] 11 with the spring-loaded plug 3 forms a labyrinth. This significantly hinders the ingress of particles such as sand or dust under pressure differences and restricts access for small animals. The outer surface 7 of the flap 2 is advantageously flush with the outer skin of the rail vehicle. The plug 3 is securely located inside the flap 2 for the filling port 5. No loose parts are used, thus eliminating the need for additional steps during servicing. Due to the preload of the spring 4, no impermissible overpressure can build up. In the event of ice formation, the plug 3 can yield. No impermissible forces are generated.

[0079] The drainage grooves (10), also called drainage slots, allow for the unrestricted drainage of water after filling and of condensation. This prevents sand from accumulating inside the drinking water tank, especially in sandy or dusty environments.

Claims

202416991 12 Patent claims 1. Flap device (1) for a rail vehicle (11) for covering a filling connection (5) of a drinking water system of the rail vehicle (11), comprising a flap (2), characterized in that the flap device (1) comprises a frustoconical plug (3) which is arranged on an inner side (6) of the flap (2) and is movable against the flap (2) by deformation of a spring (4).

2. Flap device (1) according to claim 1, characterized in that the flap device (1) has at least one first hinge element (9) for forming a hinge with a second hinge element (13) of the rail vehicle (11), wherein the first hinge element (9) is arranged on the flap (2) and can be connected to the second hinge element (13) of the rail vehicle (11), so that the flap (2) can be folded onto the rail vehicle (11) by means of the first hinge element (9).

3. Flap device (1) according to one of claims 1 or 2, characterized in that the plug (3) has at least one drainage groove (10) which is provided in a lateral surface of the plug (3).

4. Flap device (1) according to one of claims 1 to 3, characterized in that the flap device (1) has a cap (8) which is arranged on the inside (6) of the flap (2), wherein the plug (3) is arranged at least partially in the cap (8).

5. Flap device (1) according to one of claims 1 to 4, characterized in that the spring (4) is arranged between the plug (3) and the inside (6) of the flap (2) to absorb pressure forces. 202416991 13 6. Flap device (1) according to one of claims 1 to 5, characterized in that the flap device (1) comprises a locking element (17) for securing the flap (2) in a folded, closed position on the rail vehicle (11).

7. Rail vehicle (11) comprising at least one drinking water system with at least one filling connection (5) and at least one flap device (1) for covering the filling connection (5) with a flap (2) which is hingedly arranged on the rail vehicle (11), characterized in that the flap device (1) is designed according to one of the preceding claims.

8. Rail vehicle (11) according to claim 7, characterized in that the rail vehicle (11) has a second hinge element (13) which is arranged on the rail vehicle (11) and is connected to the first hinge element (9) of the flap (2) in the form of a hinge, so that the flap (2) is arranged on the rail vehicle (11) in a way that allows it to be folded towards the rail vehicle (11).

9. Rail vehicle (11) according to one of claims 7 or 8, characterized in that the plug (3) for use in the filling port (5) is at least partially complementary to the filling port (5).

10. Rail vehicle (11) according to one of claims 7 to 9, characterized in that the rail vehicle (11) comprises at least one flap device (1) according to claim 4, wherein the cap (8) receives the filling connection (5) at least sectionally in a closed, folded-up position of the flap (2).

11. Rail vehicle (11) according to one of claims 7 to 10, characterized in that when closing the flap (2) from an open, unfolded position of the flap (2) to a closed, folded-down position of the flap (2), the plug (3) is inserted into an open end of the filling port (5) and centered in the filling port (5), wherein, in the closed, folded-down position of the flap (2), the plug (3) is inserted by means of the 202416991 14 spring (4) is pre-tensioned against the filling port (5) and, when the flap (2) is opened from the closed, folded position of the flap (2) to the open, unfolded position of the flap (2), the plug (3) releases the filling port (5) for filling.

Citation Information

Patent Citations

  • Covering device for covering a line opening of a drinking water line

    DE102016202078A1

  • Forced locking of a fresh water connection of a rail vehicle

    WO2017055008A1

  • Closing flap for the filling socket trough in a rail vehicle side wall, especially on long-distance passenger carriages

    DD284197B5

  • Closure for vehicle fuel container has contact bearing element on insert part movable to and fro relative to undercut section of filling pipe

    DE19853157A1

  • Vehicle fuel tank filler cap has a plug with a moving laying unit to lock into the filler pipe neck and a seal at the pipe neck rim for secure and rapid liquid / gas sealing with easy movements

    DE19931177A1