Fuel cell tower for a fuel cell system

Abstract

The present invention relates to a fuel cell tower (10) for a fuel cell system, the fuel cell tower comprising a housing (20) with a housing interior (22) in which at least two fuel cell stacks (30) are arranged one above the other along a stacking direction (SR), wherein at least one weight (40) is arranged in the housing interior (22) above the fuel cell stacks (30), in contact with the uppermost fuel cell stack (30) in a manner allowing the transmission of gravitational force (GK), for applying at least a portion of the gravitational force (GK) of the weight (40) onto the fuel cell stacks (30).

Description

[0001] Fuel cell tower for a fuel cell system

[0002] The present invention relates to a fuel cell tower for a fuel cell system, an assembly method for assembling such a fuel cell tower and a transport securing method for transport securing such a fuel cell tower.

[0003] It is known that fuel cell towers, which comprise a stacked arrangement of multiple fuel cell stacks, are used to provide electrical power. The combined electrical power of the fuel cell stacks therefore results in a greater electrical output than the individual output of a single fuel cell stack. By combining multiple fuel cell towers in a modular manner, it is possible to meet even very high demands on the electrical power to be generated.

[0004] A common problem in the design and provision of fuel cell towers is ensuring sufficient compression of the individual fuel cells within the fuel cell stacks. This is typically achieved by bracing the individual fuel cell stacks using bolts or spring force, thus creating a defined compression of the individual fuel cells against each other. However, providing such compression means specific to the fuel cell stacks is relatively complex and requires additional installation space within a fuel cell tower. In particular, additional assembly steps are necessary because each fuel cell stack must be individually braced and thus compressed.

[0005] The object of the present invention is to at least partially remedy the disadvantages described above. In particular, the object of the present invention is to provide a cost-effective and simple way of compressing fuel cell stacks in a fuel cell tower.

[0006] The above object is achieved by a fuel cell tower having the features of claim 1, a fuel cell method having the features of claim 13, and a transport securing method having the features of claim 14. Further features and details of the invention emerge from the subclaims, the description, and the drawings. Features and details described in connection with the fuel cell tower according to the invention naturally also apply in connection with the assembly method according to the invention and the transport securing method according to the invention, and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is always made to each other.

[0007] According to the invention, a fuel cell tower is provided for a fuel cell system. For this purpose, the fuel cell tower comprises a housing with a housing space in which at least two fuel cell stacks are arranged one above the other along a stacking direction. A fuel cell tower according to the invention is characterized in that at least one weight is arranged in the housing space above the fuel cell stacks. This weight is arranged in a weight-transmitting contact with the uppermost fuel cell stack for applying at least part of the weight force of the weight to the fuel cell stack.

[0008] According to the invention, the fuel cell system comprising one or more fuel cell towers according to the present invention serves to generate electrical energy. However, a reverse mode of operation is also conceivable, for example, as an electrolysis device using a weight according to the invention.

[0009] The core concept of the present invention is based on the fact that two or more fuel cell stacks are arranged one above the other within the housing space along a stacking direction. This specific arrangement in a fuel cell tower can now be utilized by an embodiment according to the invention for the compression functionality. For this purpose, at least one weight is provided, which can provide a defined weight force, for example through a correspondingly high material density and the associated material selection. If this weight is then brought into a position in which the weight force of this weight is at least partially transferred to the uppermost fuel cell stack, this transfer is followed by a corresponding compression of this uppermost fuel cell stack due to the weight force.Due to the tower-like design of the fuel cell tower and the stacked arrangement of the fuel cell stacks, this weight is transferred not only to the top fuel cell stack, but also to the other fuel cell stacks below it. In other words, the weight not only weighs down the top fuel cell stack, but also all the fuel cell stacks arranged one above the other below it. With a single weight, it is now possible to provide a compression function for all fuel cell stacks within the housing space. Furthermore, the compression force increases even further along the housing space. The top fuel cell stack is compressed the least, while the ones below it are compressed by the weight of the weight and the weight of the fuel cell stack(s) above it.

[0010] While prior art solutions required additional assembly steps to clamp and compress each individual fuel cell stack, the fuel cell stacks can be inserted into the housing space uncompressed with a design according to the invention. Preparatory clamping steps are no longer necessary, significantly reducing the complexity of the assembly process explained later.

[0011] By placing the weight on the top fuel cell stack as the final step, the required installation space in the housing can also be reduced. While a free volume is now required for the weight above the top fuel cell stack, the space required for the compression options of bracing devices for all individual fuel cell stacks is completely eliminated. In particular, this can result in the fuel cell tower being taller by the weight volume, but correspondingly slimmer by the reduction in the bracing devices. This installation space advantage is further multiplied when two or more such fuel cell towers are combined side by side in a fuel cell system.

[0012] According to the invention, a defined compression functionality can now be provided through the use of the weight. This is oriented in particular, as will be explained later, to the required minimum and maximum compressions for the individual fuel cell stacks. Of course, multiple weights can also be used, which can also be arranged between individual fuel cell stacks. However, a preferred embodiment is one in which the at least one weight is arranged exclusively or essentially exclusively on the uppermost fuel cell stack in order to introduce the weight force into the stack.

[0013] It should also be noted that it is sufficient if at least a portion of the weight force is introduced into the fuel cell stack. However, it is preferred if the weight force is applied completely or essentially completely to the uppermost fuel cell stack. The portion of the weight force actually available for weighting the fuel cell stack depends on the actual geometric orientation of the weight and the contact of the uppermost fuel cell stack with respect to the direction of gravity. Fuel cell towers are preferably positioned such that, within the scope of the present invention, the stacking direction is aligned along the direction of gravity.If the weight is placed on the top fuel cell stack in such a way that the direction of the weight force is aligned along the direction of gravity and thus along the stacking direction, it can be ensured that the entire, or essentially the entire, portion of the weight force is actually available for the compression function. By further optimizing the geometric correlation between the at least one weight and the fuel cell stack, the method of application and, in particular, the magnitude of any tipping moments can be optimized.

[0014] It can be advantageous if, in a fuel cell tower according to the invention, an insulation layer is arranged between the at least one weight and the uppermost fuel cell stack to electrically insulate the weight from the uppermost fuel cell stack. From an electrical perspective, the electrical insulation decouples the weight from the electrical functionality of the fuel cell stack. A ceramic insulation layer, in particular, can be used as the electrical insulation layer. Using a ceramic insulation layer can offer a decisive advantage in that it can improve the heat-up time of the fuel cell tower. Because fuel cell systems are frequently operated at temperatures of up to 1000 degrees Celsius, the heat-up process represents a very energetically relevant part of the operational functionality.By reducing the thermal barrier between the weight and the fuel cell stack, for example, by using a relatively thin ceramic insulation layer, the heat-up time can be improved. In particular, the thermal inertia of the entire system, consisting of fuel cell stacks and weight, is reduced in this way.

[0015] It is further advantageous if, in a fuel cell tower according to the invention, the stack centers of gravity of the at least two fuel cell stacks lie on a stack center of gravity line, which runs in particular along or substantially along a straight line. Each fuel cell stack has a defined stack center of gravity due to its specific composition of individual fuel cells. If all stack centers of gravity of all fuel cell stacks within the fuel cell tower are connected, this results in the stack center of gravity line, which accordingly illustrates the course of all stack centers of gravity of the fuel cell stacks. This stack center of gravity line can run along a curved line, but preferably it runs along a straight line or substantially along a straight line.In a tower-like arrangement with a vertical design, the stack center of gravity line is preferably aligned along the direction of gravity and thus perpendicular or substantially perpendicular to a mounting surface of the fuel cell tower in an operating situation.

[0016] It can also be advantageous if, in a fuel cell tower according to the invention, the stack center of gravity line is formed along or substantially along the stacking direction and / or substantially along a direction of gravity. The preferred solution for a fuel cell tower involves correlating the stack center of gravity line along the stacking direction and along the direction of gravity. This combines two decisive advantages. By aligning it along the stacking direction, the compactness and required installation space of the fuel cell tower are reduced to a minimum. By additionally aligning it along the direction of gravity, the maximum proportion, in particular the entire weight force of the weight, can be introduced along the direction of gravity, and thus also the stack center of gravity line.If, as explained later, the center of gravity is also located on this line, the introduction of tipping moments can be reduced even further, so that separate transfer or support of transverse forces, shear forces, or tipping moments is no longer necessary. The introduction of the weight force thus serves exclusively or essentially exclusively to generate the compression functionality, without requiring additional mechanical supports. It is also advantageous if, in a fuel cell tower according to the invention, the at least one weight has a center of gravity that is arranged on or essentially on the extension of the stack's center of gravity line. This enables the weight force to be introduced directly from above, i.e. starting from the center of gravity, into the stack's center of gravity line.By correlating the force-relevant orientations, not only is the full weight force applied to the fuel cell stack, but this also occurs along the stack's center of gravity, so that tipping moments around the individual stack centers of gravity can be completely or essentially completely avoided. Maximizing the applied weight force is thus correlated with maximizing the mechanical stability of the fuel cell tower. In particular, this increased stabilization eliminates the need for additional components for mechanical stabilization, such as lateral load-bearing straps or similar.

[0017] A further advantage can be achieved if, in a fuel cell tower according to the invention, at least one weight is made of a high-temperature-resistant material. As already indicated, the operating temperatures of fuel cell towers are frequently in the range up to approximately 1000 degrees Celsius. At such high temperatures, particularly considering shutdown times and idle temperatures in the range of ambient temperature, for example, 20 degrees Celsius, high-temperature-resistant material for the weight can improve long-term stability. In particular, embrittlement of the material and / or scaling of the weight material is avoided in this way, and the weight can thus be integrated into the high-temperature space of the housing of the fuel cell tower without any problems.It should also be noted that it is irrelevant whether the at least one weight is composed of a monoblock or of individual weight components or weight layers.

[0018] It can also be advantageous if, in a fuel cell tower according to the invention, a compensating gap is formed between the at least one weight and the housing, in particular above the at least one weight in the stacking direction, to compensate for temperature-related dimensional differences in the fuel cell stack. As already explained several times, the temperatures within the housing space fluctuate between rest temperatures of approximately 20 degrees Celsius and operating temperatures of up to 1000 degrees Celsius. All components within this housing space subject to these temperature fluctuations expand due to the high operating temperatures due to the thermal stress and reduce their dimensions again as soon as the rest temperature is reached.To compensate for these temperature-induced expansion movements, this embodiment features a compensation gap, which is arranged, in particular, as a temperature compensation gap above and / or below the fuel cell stack and / or the weight. This compensation gap can be designed either as a free compensation gap or as a compensation gap with elastically compressible material contained therein. This ensures that a defined positioning of the weight is not accompanied by undesirable increased thermally induced mechanical stresses due to dimensional changes at operating temperature.

[0019] It may also be advantageous if, in a fuel cell tower according to the invention, at least one positioning means is arranged between the housing and the at least one weight and / or between the uppermost fuel cell stack and the at least one weight to secure the position of the weight. The introduction of the weight force already provides a defined basic stabilization and positioning for the weight. By using positioning means that position the weight, in particular in a form-fitting or substantially form-fitting manner, the weight can be further secured in terms of its position.Of course, such positioning means can also include freewheels either on the side walls of the housing, on the top of the housing, and / or on the top of the fuel cell stack, in order to ensure the expansion capability described above at operating temperatures of approximately 1000 degrees Celsius. For such freewheels, these positioning means can be designed not only as positioning pins, but also as positioning ribs and / or positioning crosses.

[0020] It is furthermore advantageous if, in a fuel cell tower according to the invention, the at least one weight is surrounded by a sealing element for a gas-tight seal between an inlet side of the fuel cell stack and an outlet side of the fuel cell stack. In such a configuration, the fuel cell tower can in particular be designed with a so-called open cathode for the fuel cell stacks, i.e. with an open cathode flow towards the cathode section of all fuel cell stacks and away from the cathode section of all fuel cell stacks. In order to prevent an undesired gas bypass past the cathode of the fuel cell stacks, such a sealing element is provided. For example, a so-called ceramic paper can be provided in one or more layers as such a sealing element. Furthermore, this also avoids electrical contact with the housing.Preferably, the sealing element is not only designed to seal the weight, but also surrounds all fuel cell stacks in order to provide the desired seal for the open cathode of all fuel cells in the housing space as a common and thus uniform sealing element.

[0021] A further advantage can also be achieved if, in a fuel cell tower according to the invention, the at least one weight has at least one transport surface for force-transmitting and / or shape-transmitting contact with at least one transport securing element for safe transport of the assembled fuel cell tower. Within the scope of the invention, "force-transmitting" or "shape-transmitting" is understood to mean that the weight can be connected to a transport securing element in a force-locking or form-locking manner. As already explained, it is sufficient if the weight is placed in a defined position on the uppermost fuel cell stack. This is also unproblematic in most applications under static operating conditions.However, during transport, i.e., moving the fully assembled fuel cell tower to a site of use, this can be problematic because the weight can move unsecured from its desired and predefined position due to external movement of the fuel cell tower. In other words, this can lead to undesirable incorrect positioning of the weight during transport. If a transport surface is provided, for example, for the integration of a transport securing element, the secure positioning of the weight can be ensured even during transport. Such a transport securing device can, for example, be provided with transport securing elements that interact with the transport surface at least partially in a form-fitting and / or force-fitting manner, or at least partially in a force-fitting manner.For example, such transport securing elements can be screwed on from the outside, thus creating a defined force and / or form fit with the weight for transport. It is further advantageous if, in a fuel cell tower according to the invention, the weight force is adapted to a minimum load on the top fuel cell stack and a maximum load on the bottom fuel cell stack. For the desired compression functionality, a minimum weight force is necessary for all fuel cell stacks. At the same time, however, maximum loads must be considered in order to reliably prevent mechanical damage to the individual fuel cells in the fuel cell stack caused by excessive weight.With these two boundary conditions, a minimum load and a maximum load can be specified for all fuel cell stacks. Because the stacked arrangement of all fuel cell stacks along the stacking direction means that the weight of the lowest fuel cell stack is added to the weight of all fuel cell stacks above it, the lowest fuel cell stack is subject to the greatest load of all fuel cell stacks in the fuel cell tower. When designing the weight of the weight, the minimum and maximum loads are taken into account in order to ensure sufficient compression functionality for all fuel cell stacks while simultaneously preventing mechanical damage to all fuel cell stacks.

[0022] It is also advantageous if, in a fuel cell tower according to the invention, the fuel cell stacks are connected to one another in a force-transmitting manner, in particular along or substantially along the stacking direction. Such a force-transmitting connection is, in particular, a compressive force-transmitting connection, for example, a force-transmitting stacking of all fuel cell stacks placed directly on top of one another. Electrical insulation materials, sealing materials, or the like can be arranged between the fuel cell stacks to ensure indirect transmission of the weight force.

[0023] The present invention also relates to an assembly method for assembling a fuel cell tower according to the present invention. Such an assembly method is characterized by the following steps: - Stacking at least two fuel cell stacks along a stacking direction in the housing space of the housing,

[0024] - Arranging the at least one weight in weight-transmitting contact with the uppermost fuel cell stack in the housing space,

[0025] - Closing the housing.

[0026] By forming a fuel cell tower according to the invention, an assembly method according to the invention provides the same advantages as those explained in detail with reference to a fuel cell tower according to the invention. It is clearly evident here that the compression functionality is implemented in a single step, in the form of arranging the at least one weight, for all fuel cell stacks simultaneously, so to speak. This inventive design of the fuel cell tower clearly demonstrates a significant simplification and reduction in the complexity of the assembly method.

[0027] An additional subject of the present invention is a transport securing method for securing a fuel cell tower according to the invention. Such a transport securing method is characterized by the following steps:

[0028] - Arranging at least one transport securing element in a securing position in the housing space between the housing and the at least one weight,

[0029] - Securing at least one transport securing element in the securing position.

[0030] By securing a fuel cell tower according to the invention for transport, a transport securing method according to the invention also provides the same advantages as those explained in detail with reference to a fuel cell tower according to the invention. As already indicated, the use of the weight makes transport securing advantageous, since otherwise occurring transport forces could result in undesirable displacement of the weight.

[0031] By arranging transport securing elements, for example, in relation to transport surfaces, the weight can be bolted and thus secured in the desired position for transport. Once the fuel cell tower is reached, the transport securing element is removed accordingly, ensuring that the weight remains in the desired position for generating the compression functionality, even during transport.

[0032] Further advantages, features, and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings. They show schematically:

[0033] Fig. 1 shows an embodiment of a fuel cell tower according to the invention,

[0034] Fig. 2 is a detailed view of another embodiment of a fuel cell tower according to the invention,

[0035] Fig. 3 is a detailed view of another embodiment of a fuel cell tower according to the invention and

[0036] Fig. 4 is a detailed view of another embodiment of a fuel cell tower according to the invention.

[0037] Figure 1 schematically shows a fuel cell tower 10 of a fuel cell system. By way of example, this is designed here with four fuel cell stacks 30 arranged one above the other. All four fuel cell stacks 30 were arranged one above the other along a stacking direction SR through an opening (not shown in detail) in the housing 20 within the housing space 22 of the housing 20. This arrangement follows several general conditions. Firstly, in the present embodiment, each fuel cell stack 30 has a defined and design-related stack center of gravity SP. When stacking all the fuel cell stacks 30 one above the other along the stacking direction SR, care was taken to ensure that all stack centers of gravity SP not only lie on a common straight line, but that this stack center of gravity line SPL is aligned along the stacking direction SR.

[0038] Additionally, Figure 1 shows that the stack center of gravity line SPL is aligned not only along the stacking direction SR, but also along the parallel gravity direction SKR. This offers several advantages with respect to the weight 40.

[0039] Figure 1 shows that a weight 40 is now arranged within the housing space 22 of the housing 20 above the uppermost fuel cell stack 30. This weight is made of a high-temperature-resistant material and is therefore resistant to temperatures of up to 1000 degrees Celsius. The weight 40 also has a weight center of gravity GP, from which the weight force GK is exerted. By aligning the direction of gravity SKR, the weight force GK of the weight 40 now also follows this direction of gravity SKR. The special embodiment of Figure 1 now shows that by aligning the stack center of gravity line SPL along the stack direction SR and simultaneously along the direction of gravity SKR, the weight force GK is introduced along the force of gravity and thus along the stack center of gravity line SPL.This ensures that no lever arms form between the applied weight force GK and the individual stack centers of gravity SP, thus preventing the introduction of tipping moments. Furthermore, the direct and complete inclusion of the weight force GK also ensures the maximum compression power for the fuel cell stacks 30 with the weight 40.

[0040] Figure 2 schematically shows a partial section of a fuel cell tower 10 with respect to the upper illustration with the weight 40. Here, it can be seen that an insulation layer 50 is now additionally arranged between the weight 40 and the uppermost fuel cell stack 30. This serves to electrically insulate the weight 40 from the uppermost fuel cell stack 30. Furthermore, the fuel cell stack 30 of Figure 2 is designed as an open cathode, so that cathode feed gas can flow into the fuel cell stack 30 via an open inlet side 32. After the chemical conversion within the fuel cell stack 30, cathode exhaust gas exits the fuel cell stack 30 again on the likewise open outlet side 34 within the housing space 22.In order to prevent a bypass past the fuel cell stack 30, a sealing element 70 is provided above the weight 40 in cross-section, which sealing element is arranged not only around the weight 40, but also around all of the fuel cell stacks 30. As a further feature, the embodiment of Figure 2 shows a compensation gap 24. When heated to operating temperature of, for example, approximately 1000 degrees Celsius, the fuel cell stacks 30 expand further, in particular along the stacking direction SR. In the embodiment of Figure 2, this leads to the extension of the components increasing upwards and thus the compensation gap 24 decreasing. To ensure this, the sealing element 70 shown here is preferably designed to be elastically compressible.

[0041] Figure 3 shows a further embodiment with additional components. Pin-shaped positioning means 60 are provided here, ensuring that the weight 40 does not leave the illustrated position even during transport and / or during expansion movements of the fuel cell stack 30. Here, too, it is shown that a compensation gap 24 (not further designated) above the weight 40 provides the desired compensation functionality.

[0042] Finally, Figure 4 shows another transport securing option. A recess within the weight 40 on its upper side serves as a transport surface 42. The secured situation according to Figure 4 now shows that a transport securing element 80 is used for transporting the fuel cell stack 10. This element is screwed from the outside of the housing 20 and thus secures the weight 40 against unwanted slipping during transport movements. Once the operating position is reached, the desired functional reliability and compression functionality of the weight 40 can be restored by unscrewing and removing the transport securing element 80.

[0043] The above explanation of the embodiments describes the present invention exclusively by way of examples. List of reference symbols

[0044] 10 Fuel cell tower

[0045] 20 housings

[0046] 22 Housing space

[0047] 24 Compensation gap

[0048] 30 fuel cell stacks

[0049] 32 Entrance page

[0050] 34 Exit page

[0051] 40 weight

[0052] 42 transport area

[0053] 50 insulation layer

[0054] 60 position means

[0055] 70 Sealing element

[0056] 80 Transport securing element

[0057] SR stacking direction

[0058] SKR gravity direction

[0059] GK weight force

[0060] SP stacking center of gravity

[0061] SPL stack center of gravity line

[0062] GP weight center of gravity

[0063] SPO securing position

Claims

Patent claims 1. Fuel cell tower (10) for a fuel cell system, comprising a housing (20) with a housing space (22) in which at least two fuel cell stacks (30) are arranged one above the other along a stacking direction (SR), characterized in that in the housing space (22) above the fuel cell stacks (30) at least one weight (40) is arranged in weight force (GK) transmitting contact with the uppermost fuel cell stack (30) for applying at least part of the weight force (GK) of the weight (40) to the fuel cell stacks (30).

2. Fuel cell tower (10) according to claim 1, characterized in that an insulation layer (50) is arranged between the at least one weight (40) and the uppermost fuel cell stack (30) for electrically insulating the weight (40) from the uppermost fuel cell stack (30).

3. Fuel cell tower (10) according to one of the preceding claims, characterized in that the stack centers of gravity (SP) of the at least two fuel cell stacks (30) lie on a stack center of gravity line (SPL), which runs in particular along or substantially along a straight line.

4. Fuel cell tower (10) according to claim 3, characterized in that the stack center of gravity line (SPL) is aligned along or substantially along the stacking direction (SR) and / or along or substantially along a direction of gravity (SKR).

5. Fuel cell tower (10) according to one of claims 3 or 4, characterized in that the at least one weight (40) has a weight center of gravity (GP) which is arranged on or substantially on the extension of the stack center of gravity line (SPL).

6. Fuel cell tower (10) according to one of the preceding claims, characterized in that the at least one weight (40) is made of a high-temperature-resistant material.

7. Fuel cell tower (10) according to one of the preceding claims, characterized in that between the at least one weight (40) and the housing (20), in particular with respect to the stacking direction (SR) above the at least one weight (40), a compensation gap (24) is formed for compensating temperature-related dimensional differences of the fuel cell stacks (30).

8. Fuel cell tower (10) according to one of the preceding claims, characterized in that at least one positioning means (60) is arranged between the housing (20) and the at least one weight (40) and / or between the uppermost fuel cell stack (30) and the at least one weight (40) for securing the position of the weight (40).

9. Fuel cell tower (10) according to one of the preceding claims, characterized in that the at least one weight (40) is surrounded by a sealing element (70) for a gas-tight sealing of an inlet side (32) of the fuel cell stack (30) from an outlet side (34) of the fuel cell stack (30).

10. Fuel cell tower (10) according to one of the preceding claims, characterized in that the at least one weight (40) has at least one transport surface (42) for force-transmitting and / or shape-transmitting contact with at least one transport securing element (80) for safe transport of the assembled fuel cell tower (10).

11. Fuel cell tower (10) according to one of the preceding claims, characterized in that the weight force (GK) of the weight (40) is adapted to a minimum load of the uppermost fuel cell stack (30) and a maximum load of the lowermost fuel cell stack (30).

12. Fuel cell tower (10) according to one of the preceding claims, characterized in that the fuel cell stacks (30) are connected to one another in a force-transmitting manner, in particular along or substantially along the stacking direction (SR).

13. Assembly method for assembling a fuel cell tower (10) having the features of one of claims 1 to 12, characterized by the following steps: - stacking at least two fuel cell stacks (30) along a stacking direction (30) in the housing space (22) of the housing (20), - arranging the at least one weight (40) in weight-transmitting contact with the uppermost fuel cell stack (30) in the housing space (22), - Close the housing (20).

14. Transport securing method for a transport securing of a fuel cell tower (10) having the features of one of claims 1 to 12, characterized by the following steps: - arranging at least one transport securing element (80) in a securing position (SPO) in the housing space (22) between the housing (20) and the at least one weight (40), - Securing the at least one transport securing element (80) in the securing position (SPO).

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