WATER SUPPLY SYSTEM FOR A RAIL VEHICLE

Description

[0001] Water supply system for a rail vehicle. Technical area

[0002] The invention relates to a water supply system for a rail vehicle, in particular for a passenger rail vehicle. Such water supply systems are known, for example, from DE10 2011 088 172 A1. State of the art

[0003] Passenger rail vehicles, particularly those for long-distance travel, are equipped with a water supply to provide drinking water to passengers. Open-plan or compartment carriages typically have wet rooms at the ends of the carriage, which include water taps. Modern vehicles have both hot and cold water supplies. Couchette or sleeping cars often have a wet room in each compartment with corresponding water taps, and sometimes also showers and toilets, so the number of water taps per car is significantly higher than in purely seating cars. In rail vehicles, it is often necessary to be able to completely drain the water pipes and water tanks so that a vehicle can be parked for longer periods even when there is a risk of frost.This must be done safely and completely, even at a slightly inclined holding position, so typically a number of drain valves must be provided, which can be located near the withdrawal points and designed for manual or remote operation. Furthermore, high demands are placed on water quality, with particular emphasis on preventing contamination. If water stagnates for an extended period in pipes, for example, a branch line to a withdrawal point, microorganisms can grow in this stagnant water under unfavorable circumstances.Water supply systems with ring mains are known from building technology. These systems provide for forced flushing of all lines up to each draw-off point. Two parallel lines run from a main line to a draw-off point and are connected to each other directly at the draw-off point. To create forced flow through these two lines, a pressure reducing device (nozzle) is arranged between the respective connection points on the main line. This pressure reducing device minimally reduces the water pressure prevailing in the main line at its outlet, but this creates a pressure difference between the two connection points to the draw-off lines, so that when water flows in the main line, a flow is forced in the draw-off lines. However, these pressure reducing devices are designed in such a way that they do not allow the line to be completely emptied.Since this is generally not accepted by rail vehicle operators, a number of drain valves must be provided, especially at and between the outlets. However, as the number of drain valves increases, so does the cost of constructing the water supply system, increasing the likelihood of failure. Description of the invention

[0004] The invention is therefore based on the object of specifying a water supply system for a passenger rail vehicle in which the number of drain valves for a complete emptying of all water-carrying pipes is minimized.

[0005] The object is achieved by a water supply system having the features of claim 1 and a passenger rail vehicle according to claim 7. Advantageous embodiments are the subject of subordinate claims.

[0006] According to the basic idea of ​​the invention, a water supply system for a passenger rail vehicle is constructed, which comprises at least one water extraction point and a ring line, wherein the ring line is formed from a supply and a return line, and wherein two branch lines lead from one of the lines to the at least one water extraction point, wherein a pressure reducer is inserted between the points where the branch lines enter the line in question, and wherein the pressure reducer has a cross-sectional reduction over the flow path of the water in it, wherein in the installed position of the pressure reducer, the lowest points of the flow path in the line in question and in the pressure reducer lie on a straight line

[0007] This has the advantage that complete water drainage from the water supply system is possible under the influence of gravity, since the special design of the pressure reductions means that there are no areas in the pipes in which water can remain.

[0008] According to the invention, the water supply system comprises a ring main which is divided into a supply line and a return line. The ring main can run the entire length of the rail vehicle and in any case runs through all areas in which water extraction points are provided. The water extraction points are connected to the ring main in such a way that they are supplied in parallel by two branch lines which in turn lead from the ring main and are connected to each other at the water extraction point. Typically, the branch lines lead from the supply line, but a connection to the return line is also possible. The branch lines are connected to the ring main (i.e. either the supply or return line) at junctions (T-pieces), with a pressure reducer into which this line is inserted being provided between the junctions.The pressure reduction causes a pressure drop at the outlet, so that the two branch lines are each subjected to different water pressures. This pressure difference ensures that the branch lines continue to flow even when the water intake point is closed, preventing the water from stagnating. To achieve this, a flow must be maintained in the ring line during operation of the water supply system, which can be achieved using a pump integrated into the ring line. A water tank holds the water supply from the rail vehicle, and its contents are continuously pumped through the ring line.

[0009] For complete emptying of the water supply system, the invention provides for a horizontal arrangement of the supply and return lines, and a drain valve is to be arranged at each end of the lower line. Generally, in practical embodiments of the invention, both lines cannot be arranged at the same height, so that either the supply or the return line is arranged lower. For complete emptying, the drain valves are therefore to be arranged on the lower line in such a way that complete water drainage is possible. Particularly advantageous in this case is the arrangement at the ends of the lines, which typically run through the entire rail vehicle, and the drain valves are thus provided near the ends of the rail vehicle.The water supply is emptied into the open air or into a pipe connected to the vehicle and can always be completely emptied in any position of the rail vehicle, i.e. even on inclines and when inclined.

[0010] Complete drainage of the branch lines can be achieved by extending them upwards from the ring main. To do this, the ring main must be installed at a lower level, for example, in a side wall below the level of the water intake points.

[0011] According to the invention, the water supply system can be used for both cold and hot water, which has the further advantage of being able to draw off hot water at the draw-off points at any time, since even when not in use for a long time, the water in the branch pipes does not cool down due to the continuous flow.

[0012] The invention proposes the insertion of a pressure reducer that allows the water to drain freely under the influence of gravity. This requires that there are no steps or edges in the ring main, and thus also in the pressure reducer, even those found in conventional pressure reducers used in building installations that restrict the flow path on all sides. Even a severely rounded constriction forms a barrier within the ring main and prevents complete drainage.

[0013] According to the invention, a pressure reduction is therefore provided in which, in the installed position, the lowest points of the flow path in the line in question and in the pressure reduction lie on a straight line.

[0014] A preferred embodiment of the invention provides for the flow path for the water in the pressure reducer to be designed in such a way that it has the shape of two oblique truncated cone volumes, which are connected in series in opposite directions and merge at their smaller diameters. The oblique truncated cone volumes are dimensioned such that a continuous straight line is created at one position of their lateral surfaces. In this way, the pressure reducer can be inserted into a line. Provided that the pressure reducer is rotated along its longitudinal axis so that this straight line lies at the lowest point of the flow path, the pressure reducer fits flush into the line. This represents the installation position of the pressure reducer.

[0015] A pressure reducer according to the invention can be constructed in other ways, for example, as a tube with a cylindrical flow path and a mechanical disruption in this flow path. This disruption can be realized, for example, by a protrusion protruding into the flow path.

[0016] This shape creates a locally turbulent flow, which causes a pressure drop. This provides the advantage of ensuring a straight connection of the pressure reduction device to the ring pipeline. Brief description of the drawings

[0017] Examples include: Fig.1 Diagram of a water supply system. Fig.2 Branch to a water intake point. Fig.2 Pressure reduction. Implementation of the invention

[0018] Fig.1shows a water supply system by way of example and schematically. It shows a water supply system 1 for a rail vehicle, which comprises a water tank 10, wherein the water is pumped through a ring line by means of a pump 11. The ring line consists of a supply line 3 and a return line 4, which are connected to each other at the furthest point of the water supply system 1. A continuous water flow is maintained through the ring line, regardless of the withdrawal. A water withdrawal point 2 is shown as an example, which can typically be designed as a faucet or a shower. To simplify the illustration, Fig.1Only one ring main is shown, actual systems usually provide for two ring mains, for cold and hot water. The water extraction point 2 is supplied by a first branch line 5 and a second branch line 6, both of which lead from the inlet line 3 of the ring main. The first branch line 5 is connected to the inlet line 3 via a first junction 7, and the second branch line 6 is connected to the inlet line 3 via a second junction 8. Between the two junctions 7, 8, a pressure reducer 9 is arranged in the inlet line 3, which, when water flows through it, causes a certain pressure drop at its outlet in relation to the pressure at its inlet. Due to these two different pressures, which act at the junctions 7, 8, the branch lines 5, 6 are continuously flowed through, even when there is no flow through the water extraction point 2.If the water supply system 1 is to be completely drained, firstly the water tank 10 must be emptied, and secondly all pipes must be able to be completely drained. For this purpose, two drain valves 12 are arranged on the inlet line 3, through which the water in the pipes can drain. A drain valve 12 is arranged at each end of the inlet line 3, ensuring complete draining of the pipes even when the rail vehicle is tilted. The inlet line 3 is arranged below the return line 4 and the branch lines 5, 6, so that the water in these pipes can also drain away completely via the inlet line 3 and the drain valves 12.In a conventional design, the pressure reducer 9 represents a barrier to the draining water, particularly when the rail vehicle is tilted or in applications where multiple water extraction points 2 are provided. A pressure reducer 9 according to the invention, as shown in detail in . Fig. 3 shown, allows draining water to flow away completely through the inlet line 3 without any hindrance.

[0019] Fig.2 shows an exemplary and schematic view of a branch to a water extraction point. The branch to a water extraction point 2 is shown, which includes both a cold and a hot water supply. Two ring lines are provided for this purpose, each consisting of a supply line 3 and a return line 4. Fig. 2Only one of the two ring pipelines is marked with a reference symbol. Branch lines 5 and 6 are connected to the inlet line 3 via junctions 7 and 8 and lead to a water intake point 2. A water tap is located in Fig. 2 not shown. In the illustrated embodiment, the supply line 3 is arranged above the return line 4; accordingly, the drain valves 12 are to be arranged on the return line 4.

[0020] Fig.3shows an example and schematically a pressure reducer. It shows a section through a ring main, e.g. an inlet line 3 at the branch point to a water extraction point 2 and through a pressure reducer 9. The branch lines 5, 6 are connected to the inlet line 3 via junctions 7, 8 and a pressure reducer 9 is arranged between the junctions 7, 8. In this sectional view, the flow path in the pressure reducer 9 is visible in the form of two oblique truncated cone volumes. It is also clear that there is a continuous straight line at the lowest position of the lateral surfaces of the oblique truncated cone volumes. It is important that the pressure reducer 9 is inserted into the ring main in this position (installation position). If it were inserted twisted, the truncated cone volumes would form a barrier to flowing away water and water would stagnate in the ring main. List of names

[0021] 1Water supply system 2Water extraction point 3Inlet line 4Return line 5First branch line 6Second branch line 7First inlet point 8Second inlet point 9Pressure reduction 10Water tank 11Pump 12Drain valve

Claims

1. Water supply system (1) for a passenger rail vehicle, comprising at least one water removal point (2) and an annular line, which is formed by a supply line (3) and return line (4), characterised in that, from one of the lines (3, 4), two transmission lines (5, 6) lead to the at least one water removal point (2), wherein, a pressure reducer (9) is inserted into the respective line between the junctions (7, 8) of the transmission lines (3, 4), wherein the pressure reducer (9) has a cross-sectional reduction therein (9) across the flow path of the water, wherein, in the installed position of the pressure reducer (9), the deepest points of the flow path in the respective line and in the pressure reducer (9) lie on a straight line.

2. Water supply system (1) for a passenger rail vehicle according to claim 1, characterised in that the supply and return lines (3, 4) are arranged horizontally in the rail vehicle and a discharge valve (12) is arranged at each of the end-face ends of the line that lies deeper.

3. Water supply system (1) for a passenger rail vehicle according to claim 1 or 2, characterised in that two annular lines are provided which carry cold or hot water and each of which are connected to a common water removal point by means of transmission lines.

4. Water supply system (1) for a passenger rail vehicle according to one of claims 1 to 3, characterised in that a flow of water can be maintained in the annular line by means of a pump (11).

5. Water supply system (1) for a passenger rail vehicle according to one of claims 1 to 4, characterised in that the pressure reducer (9) has a flow path for water therein, which is constructed of two oblique truncated cone volumes.

6. Water supply system (1) for a passenger rail vehicle according to one of claims 1 to 5, characterised in that the transmission lines (5, 6) extend upwards from one of the lines (3, 4) of the annular line.

7. Passenger rail vehicle, comprising a water supply system (1) according to one of claims 1 to 6.