System for rapid filling of a cryogenic container of a vehicle

Abstract

The invention relates to a system (1) for rapid filling of a cryogenic container (2) comprising a vehicle, the cryogenic container (2) which is mounted on the vehicle, and an auxiliary system for filling the cryogenic container (2) with cryogenic fluid and for removing cryogenic fluid from the cryogenic container (2), wherein the auxiliary system comprises a filling line (5) with a filling coupling (6) and a removal line (7) which is routed to a consumer, wherein the filling line (5) and the removal line (7) are each routed separately or via a common connector line (15) into the cryogenic container, wherein the removal line (7) or the connector line (15) is thermally connected by means of a permanent or switchable heat bridge to the filling line (5) and / or the filling coupling (6), or wherein the removal line (7) is returned through a portion of the filling line (5).

Description

[0001] System for rapid refueling of a vehicle's cryogenic container

[0002] The invention relates to a system for the rapid refueling of a cryogenic container comprising a vehicle, the cryogenic container mounted on the vehicle and a secondary system for filling the cryogenic container with cryogenic fluid and for removing cryogenic fluid from the cryogenic container, wherein the secondary system comprises a filling line with a filling coupling and a removal line led to a consumer, wherein the filling line and the removal line are each led into the cryogenic container separately or via a common connecting line.

[0003] According to the current state of the art, liquefied gases can be stored in containers ("cryogenic containers") to serve as fuel for a consumer such as an engine. Liquefied gases are gases that exist in the liquid state at boiling temperature, with the boiling temperature of this fluid being pressure-dependent. If such a cryogenic liquid is filled into a cryogenic container, a pressure corresponding to the boiling temperature is established, apart from thermal interactions with the cryogenic container itself.

[0004] In automotive engineering, the cryogenic fluid can serve as fuel for a vehicle, for which purpose the cryogenic container is carried on the vehicle. Typically, cryogenic containers are mounted on the side of the vehicle frame, and the cryogenic containers must have sufficient insulation to ensure that the cryogenic fluid remains at a low temperature in the cryogenic container for as long as possible, since these containers are not actively cooled, at least not when the vehicle is stationary.

[0005] For example, hydrogen is pumped into the cryogenic vessel at a temperature of up to -253 °C. The constant heat input causes the cryogenic fluid in the vessel to continuously heat up, thereby increasing the pressure inside the vessel. As soon as the pressure in the cryogenic vessel exceeds a certain threshold, gaseous cryogenic fluid is released from the vessel to reduce the pressure. Therefore, on the one hand, the aim is to improve the insulation capacity of the cryogenic vessel to reduce the heat input and thus increase the time after which the cryogenic fluid is released from the cryogenic vessel.

[0006] On the other hand, this insulation means that the contents of the cryogenic container remain cold, while external fittings, in particular the filling coupling, remain at a warm temperature, corresponding, for example, to the ambient temperature. While this is beneficial for the general insulation quality of the cryogenic container, it slows down the refueling process. This is because when refueling with cold cryogenic fluid provided by the filling station, the warm filling coupling must first be cooled to the temperature of the cryogenic fluid. In other words, the first cryogenic fluid fed from the filling station into the filling coupling will evaporate until the filling coupling and the filling line are cold enough to transfer the cryogenic fluid into the cryogenic container without evaporating.

[0007] The object of the invention is to improve the systems known from the prior art in such a way that faster refueling of the cryogenic container is possible.

[0008] According to the invention, this object is achieved by a system for the rapid refueling of a cryogenic container comprising a vehicle, the cryogenic container mounted on the vehicle and a secondary system for filling the cryogenic container with cryogenic fluid and for removing cryogenic fluid from the cryogenic container, wherein the secondary system comprises a filling line with a filling coupling and a withdrawal line led to a consumer, wherein the filling line and the withdrawal line are each led into the cryogenic container separately or via a common connecting line, wherein the withdrawal line and / or the connecting line is thermally connected to the filling line, the filling coupling and / or a connecting line connected to the filling line by means of a permanent or switchable thermal bridge or that the withdrawal line and / or the connecting line is led back through a section of the filling line and / or the connecting line.If a permanent thermal bridge is used, it is formed by a thermally conductive connection, preferably by a cable, a mesh, a plate or a film, or by direct contact (between the extraction line or the connecting line on the one hand and the filling line or the connecting line on the other). A thermally conductive connection is understood to be a low-mass connection, i.e. one with as little mass as possible. Direct contact means that the extraction line or the connecting line is led to the filling line or the connecting line and contacts it. To ensure that a thermal connection is established, a film can be wrapped around the two contacting lines, for example.

[0009] All claimed variants have in common that a connection between the extraction and filling sections is achieved that is as massless as possible. Thus, de facto no additional mass (both in terms of thermal mass and weight mass) is added to the system, while simultaneously achieving the rapid refueling described below. If a permanent thermal bridge is provided, the added mass is limited by the one-dimensional connection (cable or mesh with point-like contacts on the lines) or two-dimensional connection (plate or foil with linear contacts on the lines). A low-mass thermal connection could also be formed by a contact piece for two essentially adjacent lines (e.g., a workpiece with two semi-cylindrical recesses on opposite sides to accommodate the lines).With direct contact, no additional mass is required at all, except for a wrap or the like. The temporary thermal bridge requires only a switch (which can be integrated into one of the thermally conductive connections mentioned above), so only a small amount of additional weight is added, and the thermal mass can even be completely removed. Routing a cable back through another cable can even reduce the weight, as cable sections are used twice.

[0010] The solution according to the invention has the advantage that the filling line is cooled during operation of the system, i.e. during the withdrawal of cryogenic fluid from the withdrawal line. Surprisingly, however, this loss of cold during withdrawal does not represent a disadvantage, but rather an advantage, since the cryogenic fluid must pass through an evaporator for heating before being supplied to the consumer in order to supply the consumer with the cryogenic fluid at a predetermined minimum temperature. In other words, the heat input into the withdrawn cryogenic fluid is actually desirable, because the consumer must be supplied with heated gas that is generally warmer than -40°C. Thus, the heat input through the cooling of the filling coupling facilitates the work of a heat exchanger (“vaporizer”) located in the withdrawal line.

[0011] By cooling the filling line or the filling coupling, it can be achieved that the filling coupling has a temperature immediately after a trip that essentially corresponds to the temperature of the cryogenic fluid, less minor heat losses at the thermal bridge, the filling line, the filling coupling, etc. As a result, cryogenic fluid can be immediately pumped into the now cold filling coupling or cold filling line after a trip, without the filling coupling having to be cooled beforehand and unnecessary time and heat energy being lost.

[0012] A further advantage is that such a thermal bridge does not increase, or does not significantly increase, the usual heat input into the cryogenic container when the vehicle is parked, especially if the measures described below, such as the thermal bridge switch or a permanent thermal bridge with connections to points on the filling line or withdrawal line with the same temperature gradient, are implemented.

[0013] In a particularly preferred embodiment, the cryogenic container has an inner tank and an outer container that is vacuum-insulated from the inner tank, and the thermal bridge or the return section is located in the space between the inner tank and the outer container. The thermal bridge or the return section is preferably located at points on the filling line and the withdrawal line where the same temperature is established after the system has been shut down. These points are generally referred to as points with the same temperature gradient. A system standstill is considered to be a state in which no cryogenic fluid is being pumped into the cryogenic container via the filling line, nor is cryogenic fluid being withdrawn via the withdrawal line. This embodiment is particularly preferred if the system does not include a thermal bridge switch, since in this embodiment no heat will flow across the thermal bridge after the system has been switched off.In this embodiment, it is further preferred if the thermal bridge on the filling line is arranged in the vacuum-insulated space, but preferably as close as possible to the outer container, ie particularly preferably directly next to it, in order to efficiently cool the filling coupling located outside the outer container.

[0014] The following explanation is put forward as background to these considerations. The "lines" of a cryogenic vessel extend, among other things, from the feedthrough points in the outer vessel to the feedthrough into the inner tank. During the hold time - i.e. no line is flowing through (no withdrawal, no refueling, no boil-off) - the heat input is particularly critical, as heat input must be minimized in order to maximize the hold time. During this phase, a temperature curve develops along each line. This begins approximately at the feedthrough point through the outer vessel with the prevailing ambient temperature (minus a few degrees for the heat transfer from the air to the outer vessel) and ends at the feedthrough point on the inner tank with the storage temperature of the cryogenic fluid.The main heat flow through this pipeline occurs through heat conduction along the pipe, heat radiation exchange with the environment, and heat convection within the pipeline. With proper design, this can be reduced to an acceptable level. The heat flow is determined by the pipe's wall thickness, the length between the inner and outer tanks, and the thermal conductivity of the pipe material, typically stainless steel. Since the cross-section and wall thickness are largely determined by safety-related objectives, the length remains the key design feature—the longer the pipe, the lower the heat flow.

[0015] In such a design, the temperature profile can be taken into account: As a first approximation, and assuming temperature-independent thermal conductivity of the pipe material and constant wall thickness, a linear temperature profile is obtained. If two pipes are connected to each other with a thermal bridge at points with the same temperature, no heat will flow across this connection due to the lack of a temperature difference, and therefore the heat flow through the pipes from the outer container to the inner tank will not experience any significant change. Local changes in wall thickness, such as valve bodies, result in a flatter temperature profile in this area (i.e., a smaller temperature difference per unit length).

[0016] During variable operating conditions, e.g., refueling, the affected pipeline will be cooled down to cryogenic fluid temperature over its entire length – from the outer container to the inner tank. This means that the inflowing cryogenic fluid will extract from the pipeline (including the valve body and all connected components) just the amount of energy required for this cooling from the initial state (stationary hold-time state, or e.g.,

[0017] The amount of energy required to heat the system (e.g., warm refueling) to the cryogenic state is calculated. This amount of energy corresponds to the heat capacity of the pipeline corresponding to this change in state. In addition, there is the removal of the heat that still flows in during refueling, for example, which is generally of secondary importance.

[0018] From the above considerations, it is once again clear that the primary objective of the invention is to enable rapid refueling by cooling the filling line during system operation. The secondary objective of the invention is to ensure that no heat flows through the thermal bridge according to the invention during system downtime, i.e., during the hold time.

[0019] Particularly when the thermal bridge is permanent, i.e., no thermal bridge switch is used, it is preferred if the heat capacity or the length of the filling line and the withdrawal line between the cryogenic vessel and the thermal bridge or the point at which the withdrawal line is returned to the filling line is essentially the same. This ensures that, after the system is shut down, no additional heat is introduced into the cryogenic vessel, i.e., both ends of the thermal bridge heat up at the same rate due to the temperature input from the outside. The time period after which cryogenic fluid is drained from the cryogenic vessel after withdrawal or refueling therefore remains unchanged compared to a system without a thermal bridge or return.

[0020] Furthermore, the length of the filling line and / or the withdrawal line between the cryogenic container and the thermal bridge or the point at which the withdrawal line is returned to the filling line is preferably substantially between 300 mm and 700 mm.

[0021] In one variant, the aforementioned thermal bridge switch can be operated manually. However, it is preferred if the system comprises a control device designed to switch the thermal bridge on and off, wherein the control unit is preferably designed to switch the thermal bridge on when cryogenic fluid is withdrawn via the withdrawal line and / or to switch the thermal bridge off when no cryogenic fluid is withdrawn via the withdrawal line. The thermal bridge switch could, in particular, be designed as a normally open switch and connected to vehicle electronics, such that the switch is opened as soon as the vehicle is stationary and closed as soon as the vehicle and / or its electronics are started.

[0022] In the case of a thermal bridge switch, it is also preferable if it is located closer to the connection point to the filling line or filling coupling than to the connection point to the extraction line.

[0023] As already mentioned, a thermally conductive connection is preferably provided for the permanent or temporary thermal bridge in order to make the connection between the extraction section and the filling section as massless as possible. A thermally conductive connection designed as a cable, mesh, plate or foil has the additional advantage that the filling section and the extraction section can be spatially spaced from one another, so that existing systems can also be retrofitted without having to re-lay the lines. The thermally conductive connection is preferably made of metal. Furthermore, a thermally conductive layer is preferably provided which surrounds the respective line, preferably an aluminum strip, which is connected to the thermally conductive connection. The secondary system therefore does not have to be redesigned because the thermal bridge can connect the spaced lines to one another.

[0024] In a further preferred embodiment, the filling line and the extraction line or the connecting line are located directly adjacent to each other at this point to form the thermal bridge and contact each other there, and / or a thermally conductive layer is provided that wraps around the two lines, and / or the two lines are spaced apart from each other at a predetermined distance, e.g., a maximum of 10 cm or 20 cm, and can be selectively contacted using the thermal bridge switch. This allows for direct heat transfer, resulting in faster cooling than with cable contact.

[0025] In vehicles, it may be advantageous to mount two cryogenic containers on the vehicle frame, e.g., one on the left and one on the right, viewed in the direction of travel, and / or at least one or at least two behind the driver's cab, horizontally and / or vertically. The two cryogenic containers can be refueled separately or together, if necessary. A further object of the invention is to enable rapid refueling of both cryogenic containers, which can be difficult due to long or separate line routes.In one aspect, the invention therefore relates to a system as described above with a second cryogenic container comprising a second filling line and a second removal line, which are each led separately or separately into the second cryogenic container, wherein the filling lines of the two cryogenic containers are optionally connected via a connecting line, by means of which both the first-mentioned and the second cryogenic container can be filled via the filling coupling of the first-mentioned cryogenic container.

[0026] In such a system with two cryogenic vessels, it is preferred if the thermal bridge thermally connects a common withdrawal line, which connects the withdrawal lines of the two cryogenic vessels, to both the filling line of the first cryogenic vessel and the filling line of the second cryogenic vessel. This is advantageous because it is not necessary to determine which cryogenic vessel the cryogenic fluid is being withdrawn from, and both filling lines can still be cooled.

[0027] Furthermore, the thermal bridge can preferably thermally connect the extraction line of the first-mentioned cryogenic container, and optionally also the extraction line of the second cryogenic container, or a common extraction line connecting the extraction lines of the two cryogenic containers, to the connecting line. Cooling the connecting line is particularly advantageous because it allows both cryogenic containers to be refueled from one side, allowing rapid refueling and equal refueling—i.e., uniform refueling of both cryogenic containers to consistently achieve the same fill volume—despite the long line distances.

[0028] The possibility of returning the extraction line through the filling line is also possible in a system with two cryogenic vessels, e.g., if a first section of the extraction line of the first cryogenic vessel, or if applicable, the common extraction line, is returned at a first point into the filling line of the first cryogenic vessel or into the connecting line and at a second point is led from the filling line of the first cryogenic vessel or from the connecting line. In addition, a return for the extraction line of the second cryogenic vessel into the filling line of the second cryogenic vessel or into the connecting line can be provided, if necessary.

[0029] Since some of the aforementioned embodiments may involve long pipe runs, it is further preferred to provide a branch line that connects two points of the extraction line and parallels the thermal bridge and / or the return point of the extraction line through a section of the filling line. This allows for situation-dependent parallel connection of the thermal bridge or the return point to temporarily reduce pressure losses.

[0030] Advantageous and non-limiting embodiments of the invention are explained in more detail below with reference to the drawings.

[0031] Figure 1 shows a system according to the invention for rapid refueling of a cryogenic container in a first embodiment with a heat-conducting cable as a heat bridge.

[0032] Figure 2 shows a variant of Figure 1, where the thermal bridge is formed by direct contact.

[0033] Figure 3 shows a variant of Figure 2, where the extraction line is led back through the filling line to form a thermal bridge.

[0034] Figure 4 shows a variant of the embodiment of Figure 1, wherein the filling line and the withdrawal line are led into the cryogenic container with a common connecting line.

[0035] Figure 5 shows a variant of the embodiments of Figure 4.

[0036] Figure 6 shows a system with two cryogenic containers that can be quickly refueled separately.

[0037] Figure 7 shows a variant of Figure 6 in which both cryogenic containers can be quickly refueled via a single filling coupling.

[0038] Figure 8 shows a variant of the embodiment of Figure 7.

[0039] Figure 9 shows a detailed view of the system according to the invention.

[0040] Figure 1 shows a system 1 comprising a cryogenic container 2 in which cryogenic fluid is stored in the gaseous state 3 or liquid state 4. The cryogenic fluid can be hydrogen, for example, so that the cryogenic container 2 is a hydrogen container, or the cryogenic fluid can be LNG (liquefied natural gas), so that the cryogenic container 2 is an LNG container. Depending on the cryogenic fluid, the cryogenic container 2 is thus designed to store cryogenic fluid at temperatures of, for example, below 150 Kelvin, in the case of hydrogen even below 50 Kelvin or below 30 Kelvin or essentially 20 Kelvin. Depending on the application, the cryogenic container 2 could, for example, be designed to store sLH2 (subcooled liquid hydrogen) or CcH2 (cryo-compressed hydrogen) and thus also be designed for correspondingly high pressures and temporarily even higher temperatures, e.g. for maximum pressures between 5 bar and 350 bar.

[0041] The system 1 further comprises a filling line 5 with a filling coupling 6 leading into the cryogenic container 2, as well as a withdrawal line 7 leading into the cryogenic container 2. The filling line 5 can have a check valve 8 blocking in the direction of the filling coupling 6. The withdrawal line 7 can, for example, have a manually or mechanically actuated shut-off valve 9 for shutting off the withdrawal line 7. As shown in Figures 1 to 3, the filling line 5 and the withdrawal line 7 can be led separately into the cryogenic container 2, or, as shown in Figures 4 and 5, the filling line 5 and the withdrawal line 7 can be led into the cryogenic container 2 via a common connecting line 15. The components for filling the cryogenic container 2 and for withdrawing cryogenic fluid from the cryogenic container 2 are generally referred to as the auxiliary system of the system 1.

[0042] The cryogenic container 2 described herein is used as a fuel tank of a vehicle (not shown in detail) and can be mounted, for example, on the vehicle frame for this purpose. To supply the cryogenic fluid as fuel to a consumer of the vehicle, the extraction line 7 is routed, for example, from the cryogenic container 2 to a consumer of the vehicle, such as an engine or a fuel cell.

[0043] If the vehicle is parked or, in general, the system 1 is not in operation and no refueling or withdrawal of cryogenic fluid from the cryogenic container 2 takes place, a temperature gradient will develop on the filling line 5 after a certain period of time after refueling, since the filling line 5 has a temperature corresponding to the cold cryogenic fluid at the point leading into the cryogenic container 2 and a temperature corresponding to the warm environment at the point of the filling coupling 6. A similar temperature gradient will develop on the withdrawal line 7 between the cryogenic container 2 and the passage on the outer container of the cryogenic container 2 or the vacuum jacket of the cryogenic container connected to the outer container. However, when the system 1 is in operation, cold cryogenic fluid will flow through the withdrawal line 7, whereby the cryogenic fluid temperature along the entire withdrawal line 7 is essentially the same cold as that in the cryogenic container 2.However, if no further precautions are used, such as the thermal bridge according to the invention explained below, the withdrawal of cold cryogenic fluid via the withdrawal line 7 would not affect the thermal gradient of the filling line 5. Therefore, at least after a longer journey, the ambient temperature will be established at the filling coupling 6 and thus the previously explained thermal gradient will be established at the filling line 5.

[0044] The problem with a warm filling path or a warm filling coupling 6 and a temperature gradient along the filling path, however, is that the cryogenic container 2 cannot be filled directly with cold cryogenic fluid. If cold cryogenic fluid were introduced into the filling coupling, the cryogenic fluid would evaporate at this point until the filling coupling 6 has essentially reached the temperature of the cryogenic fluid. Rapid filling cannot be considered in this case, since cooling the filling coupling 6 or the filling line 5 takes a certain amount of time. The evaporation of cryogenic fluid at the beginning of such a filling process also reduces the maximum mass that the cryogenic container can hold, since warmer cryogenic fluid (at the same density) generally has a lower density.

[0045] The solutions explained below in Figures 1 to 8 ensure that the filling coupling 6 is ready for operation at least immediately after the completion of the withdrawal of cryogenic fluid from the cryogenic container 2, e.g. when the vehicle stops at a filling station after a journey.

[0046] In the embodiment of Figure 1, the extraction line 7 is thermally connected to the filling line 5 by means of a switchable thermal bridge. In this embodiment, the thermal bridge is formed by a thermally conductive connection 10, e.g. a cable or a mesh, in particular made of metal such as aluminum or copper. This cable, or more generally the thermally conductive connection 10, can optionally be insulated from the outside by means of insulation such as a plastic layer. A mesh would, for example, enable multiple connection points to be present on the extraction line 7 and on the filling line 5 and also allow essentially planar heat transfer to take place. Furthermore, the thermally conductive connection 10 could be formed by a film or plate. A film differs from a plate in this respect only in its flexibility. The film or plate can also be made of metal, e.g. aluminum or copper.The heat conducting connection 10 is preferably longer than 10 cm, preferably longer than 20 cm, preferably longer than 50 cm or preferably longer than 100 cm, so that even spaced-apart lines can be connected to one another.

[0047] To connect the thermal connection 10 to the extraction line 7 or the filling line 5, a thermally conductive layer 11, in particular an aluminum strip, can be used that encompasses the respective line 5, 7 at least in sections. A first aluminum strip could thus be wrapped around the extraction line 7 and a second aluminum strip could be wrapped around the filling line 5, and the cable or network could thermally connect the aluminum strips. The thermal bridge shown in Figure 1, for example, could be realized in this way.

[0048] If the thermal bridge is permanent, i.e., if no thermal bridge switch 12 explained below is used, it is preferably provided that the heat capacity or the thermal resistance or the length of the filling line 5 and the withdrawal line 7 between the cryogenic container 2 and the connection point of the permanent thermal bridge to the respective line is essentially the same. This makes it possible to provide that the permanent thermal bridge is located at points on the lines 5, 7 with the same temperature gradient or at points where the same temperature is established during a longer standstill. In other words, after a system standstill, both the withdrawal line 7 on the consumer side and the filling line 5 on the filling coupling side heat up. If both ends of the thermal bridge heat up to the same extent, there is no heat flow across the thermal bridge when the system is stopped, i.e.does not lead to a significant heat input into the system. The length of the filling line 5 and / or the withdrawal line 7 between the cryogenic container 2 and the thermal bridge is, for example, essentially between 300 mm and 700 mm.

[0049] Figure 1 further shows that the thermal bridge could have an optional thermal bridge switch 12. The thermal bridge switch 12 is designed to prevent a thermal connection of the thermal bridge when the thermal bridge switch 12 is open. In other words, the heat conduction connection can be severed by the thermal bridge switch 12. This makes it possible, for example, for the thermal bridge to be attached at any point on the filling line 5 or withdrawal line 7 without having to consider points with the same temperature gradient. The thermal bridge switch 12 makes this solution more flexible in use, since the desired effect of cooling the filling path can be achieved even when the available installation space is very limited. The thermal bridge switch 12 is usually opened when the vehicle is parked or the system 1 is switched off, and closed when the vehicle orSystem 1 is put into operation, since from this point on cryogenic fluid will flow via the sampling line 7.

[0050] The thermal bridge switch 12 can be manually operated and, for this purpose, arranged, for example, next to the filling coupling or in a driver's cab of the vehicle. The system 1 could, however, alternatively or additionally also comprise a control unit 13 which controls the thermal bridge switch 12. The control unit 13 is in this case designed to switch the thermal bridge on and off, wherein the control unit 13 is preferably designed to switch the thermal bridge on, i.e., to close the thermal bridge switch 12, when cryogenic fluid is withdrawn via the withdrawal line 7 and / or to switch the thermal bridge off, i.e., to open the thermal bridge switch 12, when no cryogenic fluid is withdrawn via the withdrawal line 7. In order to detect a withdrawal of cryogenic fluid via the withdrawal line 7, the control unit 13 can, for example, be equipped with a sensor, e.g.a level sensor in the cryogenic container 2 or a mass flow meter in the extraction line 7 or to receive a control signal from a vehicle electronics system, which indicates, for example, consumer operation.

[0051] Furthermore, it can be seen from Figure 1 that the thermal bridge switch 12 in the thermal connection 10 can preferably be provided closer to the connection point to the filling line 5 than to the connection point to the extraction line 7. The reason for this is that during a refueling process, the possibly warm thermal connection 10 would also have to be cooled, which is avoided by the aforementioned arrangement of the switch near the filling line 5.

[0052] Figure 2 shows an embodiment in which the thermal bridge is configured as an alternative to the embodiment of Figure 1. Instead of a thermally conductive connection 10 embodied as a cable, the thermal bridge can be formed by routing the filling line 5 and the extraction line 7 such that they lie adjacent to one another at at least one point, thereby preferably contacting one another. Preferably, the two lines 5, 7 can be wrapped at this point with a thermally conductive layer 11, such as an aluminum strip, to establish or improve contact. As a result, both lines 5, 7 are partially encompassed by the thermally conductive layer 11. It can be seen that this embodiment is functionally identical to that of Figure 1 without the thermal bridge switch 12. Here, too, it can be provided that the thermal bridge is present at points on the filling line 5 or extraction line 7 with the same temperature gradient or temperature level after a prolonged period of inactivity.

[0053] Alternatively, a thermal bridge switch 12 can also be provided in the embodiment of Figure 2. For example, the lines 5, 7 could be spaced apart from one another, e.g., with a maximum mutual distance of 10 cm or 20 cm, and a contact such as a plate or a rod could contact the two lines 5, 7 in a first operating state and thermally separate them in a second operating state. This contact forms the thermal bridge switch 12 and could, for example, be pivotally connected at one end to one of the lines 5, 7, with the other end contacting the other line 5, 7 in the first operating state and maintaining a distance from the other line in the other operating state. This is shown schematically for the lower cryogenic container 2 in Figure 7.

[0054] With regard to Figures 1 and 2, it should also be noted that the arrangement of valves such as the check valve 8 in the filling line 5 can be chosen as desired, although it is preferred that the thermal bridge is located directly next to the filling coupling 6, i.e. there is no valve in the filling line 5 between the thermal bridge and the filling coupling 6. The thermal bridge can preferably be installed so close to the filling coupling 6 but still in the vacuum space that the temperatures during longer withdrawals do not fall below, for example, temperatures that are hazardous to health at the filling coupling or control surfaces in the immediate vicinity and do not fall below, for example, a temperature of -30°C, -20°C or -10°C. The filling coupling 6 can be cooled efficiently using these solutions.

[0055] Figure 3 is an embodiment that is functionally similar to that of Figure 2, wherein the filling line 5 and the withdrawal line 7 are not located next to one another, but rather the withdrawal line 7 is partially recirculated through the filling line 5. In other words, the filling line 5 and the withdrawal line 7 share a common section 14. The filling line 5 then has a first filling section between the common section 14 and the filling coupling 6 and a second filling section between the common section 14 and the cryogenic container 2. The withdrawal line 7 has a first withdrawal section between the common section 14 and the consumer and a second withdrawal section between the common section 14 and the cryogenic container 2.It is shown schematically that there is a first valve VI in the first filling section, a second valve V2 in the second filling section, a third valve V3 in the first removal section and a fourth valve V4 in the second removal section. The valves VI - V4 could be operated manually or automatically or even designed at least partly as check valves. If necessary, one or more valves VI - V4 could also be omitted. The invention is therefore not restricted to a specific arrangement of the valves V1 - V4. During a filling process, for example, the valves V3, V4 in the removal sections are blocked so that the common section.

[0056] 14 acts as a section of the filling line 5. During a withdrawal process, for example, the valves VI, V2 in the filling sections are blocked, so that the common section 14 acts as a section of the withdrawal line 7. The second withdrawal section, in which the valve V4 is shown, could also be used, at least temporarily, as a connecting line between two cryogenic containers.

[0057] Such a return of the withdrawal line 7 through the filling line 5 is advantageous because, during a withdrawal process, the common section and thus also a common section of the filling line 5 is cooled. As a result, the filling coupling is also cooled by heat conduction during the withdrawal process. It can be seen that the same effect is achieved as in the embodiments of Figures 1 and 2, ie, rapid refueling is possible immediately after the system 1 or vehicle is shut down.

[0058] Figure 4 shows an embodiment in which the filling line 5 and the withdrawal line 7 are guided into the cryogenic container 2 via a common connecting line 15, ie the filling line 5 and the withdrawal line 7 share the section of the connecting line 15. The embodiment of Figure 1 can also be provided analogously in embodiments with a common connecting line 15, wherein the thermal bridge in the form of a heat-conducting connection 10 is attached with one end to the withdrawal line 7 (ie to the connecting line 15 or to the section of the withdrawal line 7 between the connecting line

[0059] 15 and consumer) and with the other end to a section of the filling line 5 which lies between the common connecting line 15 and the filling coupling 6.

[0060] Particularly if a permanent thermal bridge is provided, the thermal bridge can be attached with one end to the section of the extraction line 7 between the connecting line 15 and the consumer, and with the other end to the section of the filling line 5 that lies between the common connecting line 15 and the filling coupling 6. This allows the thermal bridge to be attached again to points on the lines 5, 7 with the same temperature gradient, and there is no heat flow across the thermal bridge when the system is shut down. This is shown in Figure 4. In this embodiment, however, a thermal bridge switch 12 could of course also be used, as in the embodiment of Figure 1, with all the variants described above.

[0061] In a system 1 with a common connecting line 15, the thermal bridge could also be positioned asymmetrically, as shown in Figure 5. In other words, the thermal connection 10 is attached at one end to the common connecting line 15 and at the other end to the section of the filling line 5 that lies between the common connecting line 15 and the filling coupling 6. In this embodiment, it is recommended to use the described thermal bridge switch 12 to reduce the heat flow when the system is shut down, although this is not mandatory.

[0062] The variant of the system with a common connecting cable 15 can also be combined with direct contacts (Figure 2) or a return (Figure 3) as explained above.

[0063] As a rule, it can happen that the system 1 has two or more cryogenic containers 2. In a vehicle, for example, at least two cryogenic containers 2 are often carried, one on the left and one on the right of the vehicle frame. Alternatively or additionally, a further cryogenic container 2 could be arranged behind a driver's cab. Several cryogenic containers 2 could also be arranged upright behind the driver's cab, or a combination of the aforementioned possibilities, e.g. at least two cryogenic containers 2 on the side of the vehicle frame and at least one behind the cab. In the simplest case, the system of Figures 1 to 5 is duplicated, i.e. both cryogenic containers 2 have their own filling line 5 and their own withdrawal line 7, which do not interact with each other. In this case, the two subsystems could each have their own thermal bridge, as in Figures 1 to 5.

[0064] Preferably, however, a common thermal bridge is used for two cryogenic containers 2. In this sense, reference is made below to the embodiments of Figures 6 to 8, in which common thermal bridges are used.

[0065] In the embodiment of Figure 6, two cryogenic containers 2 are provided, each of which is filled via its own filling line 5 or filling coupling 6. However, the withdrawal lines 7 leading into the respective cryogenic containers 2 can be connected and led to the consumer as a common withdrawal line 16. During such withdrawal, it can happen, e.g. due to different fill levels or pressure conditions, that cryogenic fluid is temporarily withdrawn from only one of the two cryogenic containers 2. To ensure constant rapid refueling for both filling couplings 6, a heat-conducting connection 10 with a branch is provided, whereby the heat-conducting connection 10 has at least three ends. A first end is connected to the common withdrawal line 16, a second end is connected to the filling line 7 of the first cryogenic container 2, and a third end is connected to the filling line 7 of the second cryogenic container 2.This allows rapid refueling of both filling couplings 6, regardless of which cryogenic container the cryogenic fluid was withdrawn from prior to a desired withdrawal. This effect could also be achieved by using a thermally conductive connection 10 with four ends, each of which is connected with one end to the filling line 5 of the first or second cryogenic container 2 and with one end to the withdrawal line 7 of the first or second cryogenic container 2.

[0066] Figure 7 shows an embodiment in which both cryogenic containers 2 can be filled via a common filling coupling 6. For this purpose, a connecting line 17 is connected to the filling line 5 of the first cryogenic container 2 and to the filling line 5 of the second cryogenic container 2 (where the filling coupling 6 of the second cryogenic container 2 is optional, see below). If cryogenic fluid is now introduced into the filling coupling 6 of the first cryogenic container 2, the cryogenic fluid introduced therein will flow into the first and / or second cryogenic container 2 depending on the prevailing pressure conditions. Optionally, valves could be installed in one or both filling lines.

[0067] 5 and / or the connecting line 17 in order to selectively control a fluid flow into the respective cryogenic container 2. Optionally, the filling line 5 of the second cryogenic container 2 can be extended with a section 18 and have a further filling coupling 19 at one end of the section 18, as shown in Figure 7 with a dashed line. If the filling coupling 6 is provided on one side of the vehicle and the further filling coupling 19 is provided on the other side of the vehicle, a user can fill both cryogenic containers 2 simultaneously, regardless of which side they are on.

[0068] For a quick refueling of both cryogenic containers 2, it should be noted that it is not or not only a matter of a cold filling coupling 6, but also in particular of a cold connecting line 17. If, for example, only the filling line 5 and the filling coupling

[0069] 6 were cooled, but not the connecting line 17, the first cryogenic container 2 could be quickly refueled, but not the second cryogenic container 2, since the warm connecting line would cause the cryogenic fluid to evaporate. Figure 7 shows alternative possibilities for cooling the connecting line 17, which could also be combined. On the one hand, a heat-conducting connection 10 could be used, one end of which is attached to the common extraction line 16 and the other end to the connecting line 17. However, a heat-conducting connection 10 with more than two ends could also be used, with one or more ends being attached at the following locations: on the extraction line 7 intended only for the first cryogenic container 2, on the extraction line 7 intended only for the second cryogenic container 2, and / or on the common extraction line 16.Furthermore, one or more ends are attached at the following locations: At one or more points on the connecting line, at the filling line 5 intended only for the first cryogenic vessel 2, at the filling line 5 intended only for the second cryogenic vessel 2, at the filling coupling 6 and / or at the further filling coupling 19. Again, it could be provided that the heat conducting connection 10 is connected to the filling line 5 near the filling couplings 6 while still within the vacuum space, so that the cooling effect does not fall below temperatures that are harmful to health or critical for safety (oxygen liquefaction temperature).

[0070] On the other hand, the two extraction lines 7, through which only cryogenic fluid is extracted from one of the cryogenic containers 2, could each be routed to the connecting line 17 and contacted there, as described above, or a thermally conductive layer 11 could wrap around the two lines (shown for the upper cryogenic container 2) or a thermal bridge switch 12 could be present there (shown for the lower cryogenic container 2). It would also be possible to route only the common extraction line 16 to the connecting line 17, thus establishing a single contact on the connecting line 17.

[0071] In the embodiments with a thermally conductive connection 10, a permanent thermal bridge can be used, as explained above, or a thermal bridge with a thermal bridge switch 12, which is optionally controlled by a control unit 13. All variants previously described for Figures 1 to 5 are also applicable to the embodiments of Figures 6 and 7 or Figure 8, which is explained below.

[0072] An embodiment with the withdrawal line 7 being returned via the filling line 5 and the connecting line 17 is shown in Figure 8. The first withdrawal line 7 is connected here to the filling line 5. The common withdrawal line 16 is connected to the connecting line 17. It can be seen that a portion of the filling line 5 is used for both the filling and withdrawal of cryogenic fluid. Likewise, a portion of the connecting line 17 is used for both the filling and withdrawal of cryogenic fluid.

[0073] For the sake of clarity, control valves for this process are not shown; however, the filling and removal paths are schematically labeled B1, B2, E1, and E2. A valve circuit for this can be easily selected by a person skilled in the art. In the filling path B1, cryogenic fluid is introduced into the filling coupling 6 and pumped into the first cryogenic container 2 via the filling line 5, and thus also via the common section of the filling line. In the filling path B2, cryogenic fluid is introduced into the filling coupling 6 and pumped into the second cryogenic container 2 via the connecting line 17, and thus also via the common section of the connecting line 17. In the first removal path E1, cryogenic fluid is removed from the cryogenic container 2 via the removal line 7 and fed to the common removal line 16 via the common section of the filling line 5 and the common section of the connecting line 17.

[0074] Optionally, a further branch line 20 can be provided between the respective withdrawal line 7 and the common withdrawal line 16 in order to conduct cryogenic fluid via the withdrawal path E2 and thus reduce pressure losses in the system. If, for example, it is determined that the connecting line 17 and / or the filling lines 5 and / or the filling couplings 6, 19 are cold enough or a quick start is not desired, cryogenic fluid can be selectively withdrawn via the withdrawal path E2 via the branch line 20, thereby reducing line paths and consequently pressure losses. This could also be provided in the embodiment explained with reference to Figure 7. The temperature of the respective lines can be measured by sensors. A or the aforementioned control unit 13 can preferably automatically connect or disconnect the branch line 20 based on the data measured by the sensors.The parallel branch line 20 in the withdrawal line 7 could also be used in other embodiments, even with only one cryogenic container 2, in particular to shorten long line paths that can occur with direct contacts as in Figure 2 or with returns as in Figure 3.

[0075] As an alternative to the variant shown in Figure 8, only the common extraction line 16 can be returned through the connecting line 17 or the respective extraction lines 7 can be returned only through the connecting line 17 or only through the respective filling line 5.

[0076] It is further understood that the thermal bridges do not have to be designed symmetrically, as shown in Figures 6 to 8. For example, an embodiment such as the upper cryogenic container 2 in Figure 7 could be used for one of the cryogenic containers 2, and an embodiment such as the lower cryogenic container 2 in Figure 8 could be used for the other cryogenic container 2, with additional valves optionally being used to control the cryogenic fluid flow. This system could optionally include an additional thermal bridge switch 12. Other combinations of the thermal bridges described herein for a system with two cryogenic containers 2 are also possible.

[0077] When it is stated herein that, for example, the heat-conducting connection 10 contacts the filling line 5, the extraction line 7, the common extraction line 16 or the connecting line 17, the contact can either be made at specific points, e.g. if the heat-conducting layer 11 is wound around the respective pipe at a specific point. Alternatively, a surface contact can also be provided, e.g. if the heat-conducting layer surrounds the respective line over a specific length. Furthermore, as an alternative, several point contacts could also be provided, e.g. if the heat-conducting layer 11 is divided at the end into several strands which are attached to the respective line at several different points, e.g. are wound around the respective line at several points.

[0078] Furthermore, reference is made above to the fact that the thermally conductive connection 10 contacts the filling line 5 or the connecting line 17. It is understood that with such contacting by thermal conduction, the filling coupling 6 or the filling couplings 6, 19 are also cooled. However, it can alternatively or additionally be provided that the thermally conductive connection 10 directly contacts the respective filling coupling 6, 19.

[0079] Figure 9 shows that the cryogenic container(s) 2 described herein typically comprise an inner tank 21 and an outer container 22 that is vacuum-insulated from the inner tank 21. It can be seen that part of the filling line 5 and part of the withdrawal line 7 are located within this vacuum-insulated space between the inner tank 21 and the outer container 22. If such a system is brought to a standstill, i.e., no cryogenic fluid flows through the lines 5, 7, heat will be introduced into the cryogenic container 2 via the respective line 5, 7, since there is a temperature difference between the interior of the inner container 2 and the exterior of the outer container 22. In other words, a temperature gradient is established at the respective line 5, 7. Preferably, the thermal bridge or the return section is located entirely within the outer container 22 and is located at points with the same temperature gradient, i.e.at points on the filling line 5 and the extraction line 7 where the same temperature is established after the system has come to a standstill. This means that there is no heat flow across the thermal bridge or section. Alternatively, the thermal bridge or the return section could be located entirely outside the outer container 22, although here too there would be no heat flow across the thermal bridge or section. It is understood that in the embodiment of Figure 9, a thermal bridge switch 12 could also be used for the thermal bridge, which in this case could also be located entirely inside the outer container 22. A control line connected to the thermal bridge switch 12 could be led to a control unit 11 located outside the outer container 22.

[0080] In all embodiments, the thermal bridge, e.g. if it is designed as a heat conducting connection 10, could also be connected at one end to one of the lines 5, 7 in the space between the inner tank 21 and the outer container 22 and at the other end to the other line 5, 7 or the connecting line 17 outside the outer container 22.

Claims

Claims:

1. System (1) for rapid refueling of a cryogenic container (2) comprising a vehicle, the cryogenic container (2) mounted on the vehicle, and an auxiliary system for filling the cryogenic container (2) with cryogenic fluid and for removing cryogenic fluid from the cryogenic container (2), wherein the auxiliary system comprises a filling line (5) with a filling coupling (6) and a withdrawal line (7) leading to a consumer, wherein the filling line (5) and the withdrawal line (7) are each led separately or via a common connecting line (15) into the cryogenic container, characterized in that a) the withdrawal line (7) and / or the connecting line (15) is thermally connected to the filling line (5), the filling coupling (6), and / or a connecting line (17) connected to the filling line (5) by means of a permanent or switchable thermal bridge, wherein the permanent thermal bridge is provided by a thermally conductive connection, preferably a cable, a mesh, a plate, or a film.or a direct contact is formed, or b) that the extraction line (7) and / or the connection line (15) is routed back through a section of the filling line (5) and / or the connecting line (17).

2. System (1) according to claim 1, wherein the cryogenic container (2) has an inner tank (21) and an outer container (22) which is vacuum-insulated from the inner tank (21) and the thermal bridge or the section for recirculation is located in the space between the inner tank (21) and the outer container (22), wherein the thermal bridge or the section for recirculation is preferably located at points on the filling line (5) and the extraction line (7) where the same temperature is established after the system has been idle.

3. System (1) according to claim 1 or 2, further comprising a control device (13) configured to switch the thermal bridge on and off, wherein the control unit (13) is preferably configured to switch the thermal bridge on when cryofluid is withdrawn via the extraction line (7) and / or to switch the thermal bridge off when no cryofluid is withdrawn via the extraction line (7).

4. System (1) according to one of claims 1 to 3, wherein the thermal conducting connection (10) is made of metal, and / or wherein a thermal conducting layer (11) encompassing the respective conductor (5, 7, 15) is provided, preferably an aluminum strip, which is connected to the thermal conducting connection (10).

5. System (1) according to one of claims 1 to 3, wherein the filling line (5) and the extraction line (7) or the connecting line (15) are located directly next to each other at this point to form the thermal bridge and make contact there and / or wherein a thermally conductive layer (11) is provided wrapping the two lines (5, 7) and / or wherein the two lines (5, 7) are spaced apart from each other at a predetermined distance, which is, for example, a maximum of 10 cm or 20 cm, and can be selectively contacted by means of the thermal bridge switch (12).

6. System (1) according to one of claims 1 to 5, further comprising a second cryogenic container (2) with a second filling line (5) and a second extraction line (7), wherein the filling lines (5) of the two cryogenic containers (2) are optionally connected via a connecting line (17), by means of which both the first and the second cryogenic container (2) can be filled via the filling coupling (6) of the first cryogenic container (2).

7. System (1) according to claim 6, wherein the thermal bridge thermally connects a common extraction line (16), which connects the extraction lines (7) of the two cryocontainers (2), both to the filling line (5) of the first cryocontainer (2) and to the filling line (5) of the second cryocontainer (2).

8. System (1) according to claim 6 or 7, wherein the thermal bridge thermally connects the extraction line (7) of the first cryocontainer (2), and optionally also the extraction line (7) of the second cryocontainer (2), or a common extraction line (16) which connects the extraction lines (7) of the two cryocontainers (2), to the connecting line (17).

9. System (1) according to one of claims 6 to 8, wherein a first section of the withdrawal line (7) of the first cryocontainer (2), or optionally the common withdrawal line (16), is returned at a first point to the filling line (5) of the first cryocontainer (2) or to the connecting line (17) and is led out of the filling line (5) of the first cryocontainer (2) or out of the connecting line (17) at a second point.

10. System (1) according to any one of claims 1 to 9, comprising a branch line (20) which connects two points of the extraction line (7) and the thermal bridge and / or the The return of the extraction line (7) is connected in parallel through a section of the filling line (5).

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