DE102017217814B4 - Battery case for a vehicle - Google Patents

Abstract

Battery housing (1) for a vehicle, comprising - a box (2) which is formed from a laterally encircling outer frame (3) and at least one first base (4), - a carrier frame (6) with a laterally encircling boundary (6.1) and a compartment structure (6.4) formed within the lateral boundary by at least one cross member (6.2) and / or at least one longitudinal member (6.3) for receiving battery elements, which is arranged in one piece from plastic in the interior (2.1) of the box (2), a cover (9) for at least partially covering the interior (2.1) of the box (2), characterized in that the circumferential lateral boundary (6.1) of the support frame (6) in the lower area has a flat flange surface (6.12) for sealing connection with having a second floor (8).

Description

Technical area

The invention relates to a battery housing for a vehicle.

Technical background

The increasing or sustained electrification of vehicles, in particular automobiles, and the simultaneous customer demand for long ranges of such vehicles, require the development of powerful battery concepts. In particular, battery housings, which accommodate the batteries or in which the batteries are integrated, generally have a substantial extent over the vehicle floor, which in particular is located essentially below the passenger cell of the vehicle. This results in complex requirements with regard to the factors of installation space, crash performance, weight, tightness, etc.

The battery housing is particularly important in order to be able to guarantee a high level of operational safety in the event of a crash. The battery housing must be able to withstand significant mechanical loads that can act laterally, frontally, rearwardly or also from below. The loads that occur can be represented by quasi-static equivalent load cases, the handling of which can, however, be very demanding, since as far as possible no damage to the battery or individual battery elements should occur.

Battery housings for vehicle batteries are well known. Essentially two designs are known from the prior art. The first design is a so-called built-up battery housing made of sheet metal, cast and / or profile components. This has a good ratio of crash performance and installation space requirement in relation to the essentially sealed interior of the battery housing that can effectively be used for the battery or battery elements. Sealing the interior of the battery housing, especially in the corners, represents a major challenge, since several components have to be joined together in the corners, so that the tightness can be impaired as a result. The second construction is formed by battery housings, in which the sealed interior of the battery housing is provided by a trough-like, essentially one-piece component. The trough-like component is relatively easy to seal by a cover which is essentially flat and which, if necessary, can be reinforced inside and / or outside by additional components in terms of better crash performance. A major disadvantage of deep-drawn, trough-like components in particular is that draft bevels and large radii must be provided along the edges and in the corners, which reduce the installation space inside the housing.

In both designs, the accessibility for mounting the battery or battery elements is also very limited and only possible from one side, mostly only from above. As a rule, a large number of different small parts, such as screw-on domes, plates or consoles, are required, which have to be connected in complex processes during the production of the battery housing. The assembly clearances are typically small. In both designs, a cover must be used to cover the interior of the battery housing, which must be designed to be removable for repair and maintenance, which makes a complex sealing solution necessary.

The prior art includes the laid-open documents JP 2016-29658 A , US 2012/0301765 A1 and EP 2 741 343 A1 .

In relation to the prior art, there is a need for a battery housing which, in particular, combines the advantages of the two types of construction and at the same time simplifies the manufacturing process and the assembly effort when inserting the battery or battery elements.

Summary of the invention

The invention is based on the object of providing a battery housing for a vehicle that is improved compared to the prior art.

This object is achieved by a battery housing for a vehicle having the features of patent claim 1. Further advantageous embodiments of the invention are listed in the subsequent claims.

• - einen Kasten, welcher aus einem insbesondere seitlich umlaufenden Außenrahmen und zumindest einem ersten Boden gebildet ist,
• - einen Trägerrahmen mit einer seitlich umlaufenden Begrenzung und einer innerhalb der seitlichen Begrenzung durch mindestens einen Querträger und/oder mindestens einen Längsträger gebildete Fachstruktur zur Aufnahme von Batterieelementen, welcher einstückig aus einem Kunststoff, insbesondere im Spritzgussverfahren hergestellt, im Innenraum des Kastens angeordnet ist,
• - einen Deckel zum zumindest bereichsweisen Abdecken des Innenraums des Kastens, umfasst.

According to the invention, a battery housing for a vehicle is provided which

• - A box, which is formed from an in particular laterally circumferential outer frame and at least one first base,
• - A support frame with a laterally circumferential boundary and a compartment structure formed within the lateral boundary by at least one cross member and / or at least one longitudinal member for receiving battery elements, which is made in one piece from a plastic, in particular in Injection molding made, located in the interior of the box,
• - A cover for at least partially covering the interior of the box, comprises.

The inventors have found that by providing a support frame made of plastic, which is produced in particular by injection molding, better utilization of the installation space compared to the prior art through a circumferential, essentially vertically continuous, lateral, essentially pointing in the direction of the interior of the box Boundary and a largely substantially rectangular shape can be provided by a compartment structure formed within the lateral boundary by at least one cross member and / or at least one longitudinal member for receiving battery elements. Due to the one-piece, circumferential lateral delimitation, an essentially tight design in the corners of the carrier frame / battery housing is guaranteed, so that the outer frame is no longer subject to the very high requirements in terms of tightness and the associated expense for manufacturing the corners in particular. The geometry, in particular the cross section of the circumferential lateral boundary, is essentially not subject to any limits, in particular due to the preferably injection molding process. For example, recesses can be provided on the outer side of the lateral boundary facing away from the interior, so that in particular stiffening structures, for example in the form of ribs and / or honeycombs, can be formed.

The side of the lateral delimitation facing the interior space can be designed to be essentially planar, at least in sections, and almost sharp-edged in the corners. The support frame can be reinforced at least in some areas and / or as required with fillers suitable for the injection molding process and the selected material. Furthermore, the design of the carrier frame, which is open at the top and optionally at the bottom, considerably simplifies accessibility and, associated with this, the assembly of the battery elements. The cover and the second base, which functions as underrun protection, consist in particular of a metallic material, preferably of a steel material, particularly preferably of a steel material with a tensile strength of at least 780 MPa each. Alternatively, the cover and / or the underrun protection can consist of a plastic, whereby the total weight of the battery housing can be reduced, but the use of plastic can affect the crash performance, which is worse compared to the use of metallic materials. The outer frame is preferably assembled from one or more profiles, which in particular consist of a metallic material, preferably a steel material with a tensile strength of at least 1000 MPa, particularly preferably a hardened steel material with a tensile strength of at least 1500 MPa. With increasing tensile strength, the resistance also increases in the event of a crash, in particular if the outer frame must not deform at all or even slightly in the event of a crash in order to protect the carrier frame or the battery elements received in the carrier frame from damage.

According to a first embodiment, the cross member (s) with the longitudinal member (s) and / or one or more crossing points of the cross member (s) with the lateral boundary and / or one or more crossing points of the longitudinal member (s) are located on the carrier frame at one or more intersection points at least one functional element is integrated into the lateral boundary. Functional elements can be injected and / or molded on, in particular integrated, directly in the injection molding process on the carrier frame, which is preferably manufactured using the injection molding process. Functional elements can be, for example, assembly elements for battery elements, in particular in the form of injected nuts in screw jacks; Fastening elements for mechanically joining the cover and / or base, in particular for form-fitting and / or force-fitting joining, for example in the form of snap hooks, latching hooks and / or screw-on domes; Spacers; Fastening elements for electrics and / or cooling elements, in particular clamps for cables, cooling pipes etc.

To increase the crash performance and in particular to prevent buckling or failure of the cross member (s) and / or the longitudinal member (s), metallic inserts are provided or integrated in the compartment structure of the carrier frame according to a further embodiment. The inserts can be in the form of a lattice structure in the carrier frame, preferably made by injection molding, in particular directly encapsulated in the injection molding process, or inserted or received in cavities provided for this purpose in the finished carrier frame, optionally fixed and / or, if necessary, encapsulated so that the inserts in the or the cross members and / or are integrated in the longitudinal member or members of the support frame and serve to reinforce the interior of the box.

According to a further embodiment, the circumferential lateral delimitation of the support frame has, at least in the upper region, an essentially flat upper flange surface for, in particular, a sealing connection with the cover. The lid with the upper one is preferred The flange surface of the support frame is joined, in particular cohesively, preferably glued and / or mechanically joined with sealing means, in particular by a form-fitting and / or force-fitting, preferably releasable connection. Regardless of the type of connection between the cover and the upper flange surface of the support frame, a tight connection must be ensured in order to prevent foreign substances, in particular splashing water, from entering the interior or battery compartment during operation when the battery housing is installed.

According to a further embodiment, the circumferential, essentially flat, upper flange surface has a seal that is already integrated into the support frame. This can be inserted as a separate component into an optionally present groove in the flange surface or in the cover.

According to a further embodiment, a profile, also called a mounting profile, which is arranged at least in sections to connect the battery housing to the vehicle, is connected to the outer frame. The mounting profile can be composed of one or more parts and in particular consist of a metallic material, preferably a steel material with a tensile strength of at least 980 MPa. The mounting profile is in particular connected to the outer frame in a materially bonded manner. The outer frame and the mounting profile are preferably welded to one another in order to be able to provide a particularly stable design of the battery housing.

According to the invention, the circumferential lateral delimitation of the support frame in the lower region has an essentially flat lower flange surface for, in particular, a sealing connection with a second base. The second base is preferably joined to the lower flange surface of the support frame, in particular cohesively, preferably glued and / or mechanically joined with sealing means, in particular by a form-fitting and / or force-fitting, preferably releasable connection. The second base consists in particular of a metallic material, preferably of a steel material with a tensile strength of at least 780 MPa. Regardless of the type of connection between the second floor and the lower flange surface of the support frame, a tight connection must be ensured in order to prevent foreign substances, in particular splashing water, from penetrating into the interior or battery compartment during operation with the battery housing installed.

According to a further embodiment, a seal is molded onto the flange surface in the upper and / or lower area of the support frame. The integration provides a seal for a detachable connection to the cover and / or the second base, in particular captive with sufficient tightness.

In order to simplify downward sealing, according to an alternative embodiment, the support frame can be designed in one piece with a second base. This is preferably also taken into account in the injection molding process of the carrier frame, so that a carrier frame that is only open at the top and sealed at the sides and at the bottom can be provided in a battery housing. Particularly preferably, channels are formed in one piece or integrated in the second base on the side facing away from the compartment structure, so that cooling channels for the later passage of cooling media are preferably also taken into account in the injection molding process, whereby the number of parts and the assembly effort can be reduced. An advantage of the integrated cooling channels compared to cooling arranged under the second floor is the avoidance of component transitions and thus more effective heat transfer. The channels can be produced, for example, using an injection molding process.

The first floor or underrun protection and the second floor together, in particular with the lower part of the surrounding outer frame, form a space, also called a cooling space, in which cooling elements for cooling the interior or the cooling space and other elements are arranged in particular. In order to allow easy access to these elements or the cooling space, in particular when the battery housing is installed, the first floor or the underrun protection is detachably connected to the outer frame according to a further embodiment.

Between the first floor or underrun protection and the second floor, elements can be used which transmit stresses acting on the underrun protection from below into the adjacent structure. This can be, for example, profile-like carriers which are attached to the underrun protection or to the second floor. In the embodiment in which the support frame is made in one piece with a second base, for this purpose at least one support rib, which is integrated in the base on the side of the support frame facing away from the compartment structure, can be exposed downwards by the injection molding process and / or via, for example the provision of metallic inserts can be extended down to the underrun protection.

Some large battery housings are not only connected to the body on the mounting profile, but can also have additional fastenings to the body within the battery compartment. In these cases, sleeves are used, for example, which seal the interior or battery compartment from the cover and from the first and / or second base, so that it can be screwed through the sleeve from below. The production and integration of sleeves made of metal is complex in terms of production technology. In the case of a carrier frame made of plastic, the at least one sleeve can be integrated without additional manufacturing effort. The at least one sleeve is provided with a seal at the top of the contact surface for the cover and at the bottom of the contact surface for the first and / or second floor or the underrun protection, which seal is preferably molded on. A plurality of sleeves are preferably integrated in the compartment structure of the support frame or made in one piece with the support frame.

• - Geringere Entformschrägen und kleinere Radien entlang der Kanten und in den Ecken gegenüber beispielsweise tiefgezogenen Wannen ermöglichen mehr Bauraum für die Batterie respektive Batterieelemente,
• - Gute Zugänglichkeit bei der Montage der Batterieelemente,
• - Der einstückige Trägerrahmen ist entlang des Rahmens dicht und gegenüber dem Boden und dem Deckel steht eine ebene, ununterbrochene Dichtfläche zur Verfügung,
• - Trennung von Innenraum/Batterieraum und Kühlraum,
• - Aufgrund der geringen Dichte ist der Kunststoff Gewichtseffizient,
• - Das Kunststoffbauteil ermöglicht die Integration von Funktionen z.B. die Anbindungsstellen der Batterieelemente oder Fixierungsmöglichkeiten für Kabel und/oder Schläuche,
• - Da der Kunststoff isolierend ist, wird die Gefahr von Kurzschlüssen bei Beschädigung des Batteriegehäuses reduziert.

The preferred use of a support frame formed in one piece from a plastic has the following advantages over known battery housings:

• - Lower draft angles and smaller radii along the edges and in the corners compared to, for example, deep-drawn tubs allow more installation space for the battery or battery elements,
• - Good accessibility when assembling the battery elements,
• - The one-piece support frame is tight along the frame and a flat, uninterrupted sealing surface is available opposite the bottom and the lid,
• - Separation of interior / battery room and cold room,
• - Due to the low density, the plastic is weight efficient,
• - The plastic component enables the integration of functions, e.g. the connection points of the battery elements or fixing options for cables and / or hoses,
• - Since the plastic is insulating, the risk of short circuits if the battery housing is damaged is reduced.

Figure list

• 1) eine Explosionsdarstellung eines ersten Beispiels eines Batteriegehäuses,
• 2 a, b) das erste Beispiel des Batteriegehäuses in unterschiedlichen Darstellungen,
• 3 a - c) ein zweites Beispiel eines Batteriegehäuses in unterschiedlichen Darstellungen,
• 4) ein drittes Beispiel eines Batteriegehäuses in einer Teilschnittdarstellung und
• 5) ein viertes Beispiel eines Batteriegehäuses in einer Teilschnittdarstellung.

The invention is explained in more detail below with reference to drawings. The same parts are always provided with the same reference symbols. Show in detail:

• 1 ) an exploded view of a first example of a battery case,
• 2 a, b ) the first example of the battery case in different representations,
• 3 a - c ) a second example of a battery case in different representations,
• 4th ) a third example of a battery housing in a partial sectional view and
• 5 ) a fourth example of a battery housing in a partial sectional view.

Description of the preferred embodiments

In 1 is an exploded view of a first example of a battery case ( 1 ) shown. The battery case ( 1 ) includes a box ( 2 ), which consists of an outer frame ( 3 ) and a first floor / underrun protection ( 4th ) is formed. The outer frame ( 3 ) is preferably assembled from one or more profiles, which in particular consist of a metallic material, preferably steel material. The first floor / underrun protection ( 4th ) consists in particular of a metallic material, preferably steel material and is preferably detachable with the outer frame ( 3 ) connected. On the outer frame ( 3 ) is a profile / mounting profile arranged at least in sections to connect the battery housing to a vehicle ( 5 ) connected. The profile / mounting profile ( 5 ) can be composed of one or more parts, which in particular consist of a metallic material, preferably steel material. The battery housing further comprises a support frame ( 6th ) with a circumferential border ( 6.1 ) and one within the lateral boundary ( 6.1 ) by at least one cross member ( 6.2 ) and / or at least one longitudinal beam ( 6.3 ) formed specialist structure ( 6.4 ) to accommodate battery elements (not shown), which are made in one piece from plastic, in particular made by injection molding, in the interior ( 2.1 ) of the box ( 2 ) is arranged. Furthermore, metallic inserts ( 7.1 ) to reinforce the interior ( 2.1 ) of the box in the subject structure ( 6.4 ) of the carrier frame ( 6th ) provided, which looks like a lattice structure ( 7th ) especially in the finished support frame ( 6th ) are inserted or received in the intended cavities, optionally fixed and / or possibly encapsulated so that the insert parts ( 7.1 ) in the cross members ( 6.2 ) and in the side members ( 6.3 ) of the carrier frame ( 6th ) are introduced. There is also a second floor ( 8th ) is provided, which is connected to the support frame ( 6th ) is connected and in particular consists of a metallic material, preferably steel material. For covering the interior in areas ( 2.1 ) of the box ( 2 ) or the interior of the Subject structure ( 6.4 ) is a lid ( 9 ) is provided, which is connected to the support frame ( 6th ) is connected and in particular consists of a metallic material, preferably steel material. The inside of the side border ( 6.1 ) of the carrier frame ( 6th ) is preferably flat, in particular essentially vertical (+/- 5 °) and the outside preferably has recesses, so that in particular stiffening structures, for example in rib and / or honeycomb shape ( 6.13 ) are trained. For the sake of clarity, further elements, such as, for example, elements for cooling, electrics, etc., are not shown, not even in the following figures.

The 2a) and 2 B) show the first example of the battery case ( 1 ) in plan view, without cover ( 9 ) for better representation ( 2a) ), and a partial sectional view ( 2 B) ) along the line AA in 2a) , especially when assembled. Partial section ( 2 B) ) it can be seen that the mounting profile ( 5 ) is composed of two parts, which are connected to the outer frame ( 3 ) are connected. The upper area of the mounting profile ( 5 ) is flat, in particular designed horizontally for connection to a vehicle. Means for releasable connection can be, for example, screws, which are secured by the mounting profile ( 5 ) introduced through holes ( 5.1 ) can be pushed through. In the corners of the lateral boundary ( 6.1 ) as well as at the crossing points of the cross members ( 6.2 ) with the side members ( 6.3 ) and at the crossing points of the cross members ( 6.2 ) with the lateral limitation ( 6.1 ) as well as at the crossing points of the side members ( 6.3 ) with the lateral limitation ( 6.1 ) are functional elements ( 6.5 ) in one piece with the support frame ( 6th ) trained or integrated. The functional elements ( 6.5 ) are, for example, screw jacks that are designed as a negative shape of a screw, through which a screw (not shown) can be pushed through from below, the screw head being received or sunk in the negative shape in particular in a rotationally secure manner by a corresponding section, and the shaft or . the thread of the screw into the inner area ( 2.1 ) or battery compartment protrudes. The battery elements have, for example, at their corners, in turn, connection elements with through openings, through which the shaft of a screw is inserted and the battery elements can be screwed firmly against the screw jacks by means of nuts. Alternatively, and not shown, nuts can also be integrated, in particular injected, into the screw-on brackets. In the cross members ( 6.2 ) and in the side members ( 6.3 ) of the carrier frame ( 6th ) are metallic inserts ( 7.1 ) introduced, which may be provided with an optional casting compound ( 10 ) within the transverse and longitudinal beams ( 6.2 , 6.3 ) are fixed. The outside of the side boundary ( 6.1 ) of the carrier frame ( 6th ) has a rib and / or honeycomb shape ( 6.13 ) on. The circumferential side boundary ( 6.1 ) of the carrier frame ( 6th ) has an essentially flat upper flange surface ( 6.11 ) and in the lower area an essentially flat lower flange surface ( 6.12 ) on. Both in the upper and in the lower flange surface ( 6.11 , 6.12 ) there is one groove ( 6.111 , 6.121 ) is provided, in each of which a sealing means, for example in the form of a sealing ring or band, is arranged. The lid is preferred ( 9 ) with the upper flange surface ( 6.11 ) of the carrier frame ( 6th ) connected by a form-fitting and / or force-fitting, preferably releasable connection. The second floor ( 8th ) is, for example, firmly bonded to the lower flange surface ( 6.12 ) of the carrier frame ( 6th ) tied, especially glued. The first floor ( 4th ) can, for example, be positively and / or non-positively, preferably detachable with the outer frame ( 3 ) be connected. In the one between the floors ( 4th , 8th ) formed space / cold room ( K ) elements of cooling, electrics etc. (not shown) can be accommodated. Since metals have a higher thermal conductivity than plastics, there are covers ( 9 ) and second floor ( 4th ) made of metal to remove the heat generated by the battery elements during operation from the interior / battery compartment ( 2.1 ) to be able to dissipate better.

The 3a) to 3c ) show a second example of a battery case ( 1 ) in plan view, without cover ( 9 ) for better representation ( 3a) ), a partial sectional view ( 3b) ) along the line AA in 3a) , and a partial sectional view ( 3c )) along the line BB in 3a) especially when assembled. In contrast to the first example in the 2a) and 2 B) is the support frame ( 6th ) in one piece with a second floor ( 6.6 ) executed. This is preferably made in the injection molding process of the support frame ( 6th ) are also taken into account, so that a support frame that is only open at the top and sealed at the sides and at the bottom ( 6th ) in the battery case ( 1 ) can be provided. In the second floor ( 6.6 ) are on the subject structure ( 6.4 ) channels facing away from ( 6.7 ) designed or integrated in one piece, which can preferably also be taken into account in the injection molding process, through which cooling media can be passed during operation.

4th ) shows a partial cross-sectional view of a third example of a battery case ( 1 ). In the specialist structure ( 6.4 ) of the carrier frame ( 6th ) there is at least one sleeve ( 6.8 ) integrated, which is integral with the support frame ( 6th ) is formed, which can be taken into account in the injection molding process in particular. The sleeve ( 6.8 ) seals the battery compartment ( 2.1 ) from. Through the sleeve ( 6.8 ) additional screw connections can be made to the body of a vehicle (not shown).

5 ) shows a partial sectional view of a fourth example of a battery case ( 1 ). In particular, at least one support rib ( 6.9 ) in the ground ( 6.6 ) on the subject structure ( 6.4 ) integrated facing away, which goes down into the cold room ( K ) is highlighted and thus loads from the underrun protection ( 4th ) can forward into the structure. In the support rib ( 6.9 ) an opening with a thread can also be provided, for example to provide an additional connection or screw connection of the underrun protection ( 4th ) with the carrier frame ( 6th ) to enable.

The invention is not limited to the embodiments shown, but the individual features can be combined with one another as desired. The battery housing ( 1 ) are used in passenger vehicles, commercial vehicles, trucks, special vehicles, buses, omnibuses, whether with hybrid or purely electric drive, but also in rail-bound vehicles such as trams or passenger wagons.

List of reference symbols

1

Battery case

2

box

2.1

Interior of the box, battery room

3

Outer frame

4th

first floor, underrun protection

5

Profile, mounting profile

5.1

Through holes

6

Support frame

6.1

lateral limitation

6.11, 6.12

upper, lower flange surface

6.111, 6.121

Groove

6.13

Reinforcement structure

6.2, 6.3

Cross member, longitudinal member

6.4

Subject structure

6.5

Functional element

6.6, 8

second floor

6.7

Channel, cooling channel

6.8

integrated sleeve

6.9

Support rib

7th

Lattice structure

7.1

metallic inserts

9

cover

10

Casting compound

K

Room, refrigerator

Claims (9)

Battery housing (1) for a vehicle, comprising - a box (2) which is formed from a laterally encircling outer frame (3) and at least one first base (4), - a carrier frame (6) with a laterally encircling boundary (6.1) and a compartment structure (6.4) formed within the lateral boundary by at least one cross member (6.2) and / or at least one longitudinal member (6.3) for receiving battery elements, which is arranged in one piece from plastic in the interior (2.1) of the box (2), a lid (9) for at least partially covering the interior (2.1) of the box (2), characterized in that the circumferential lateral boundary (6.1) of the support frame (6) in the lower area has a flat flange surface (6.12) for sealing connection with having a second floor (8). Battery case after Claim 1 , characterized in that on the support frame (6) at one or more intersection points of the cross member (s) (6.2) with the longitudinal member (s) (6.3) and / or at one or more crossing points of the cross member (s) (6.2) with the lateral boundary ( 6.1) and / or at least one functional element (6.5) is integrated into one or more intersection points of the longitudinal member or members (6.3) with the lateral boundary (6.1). Battery housing according to one of the preceding claims, characterized in that metallic inserts (7.1) are integrated in the compartment structure (6.4) of the support frame (6). Battery housing according to one of the preceding claims, characterized in that the circumferential lateral boundary (6.1) of the support frame (6) has, at least in the upper region, a flat upper flange surface (6.11) for sealing connection with the cover (9). Battery case after Claim 4 , characterized in that the cover (9) is joined to the flange surface (6.11) of the support frame (6). Battery housing according to one of the preceding claims, characterized in that a profile (5) arranged at least in sections to connect the battery housing to the vehicle is connected to the outer frame (3). Battery housing according to one of the preceding claims, characterized in that a seal is injection molded onto the flange surface (6.11, 6.12) in the upper and / or lower area of the support frame (6). Battery housing according to one of the preceding claims, characterized in that the first base (4) is detachably connected to the outer frame (3). Battery housing according to one of the preceding claims, characterized in that at least one sleeve (6.8) is integrated in the compartment structure (6.4) of the support frame (6).

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