MXPA99004006A - Switching cabinet - Google Patents

Abstract

The invention relates to a switching cabinet comprising a rack endowed with horizontal and vertical frame profiles . The horizontal frame profiles form a lower and upper frame and the vertical frame profiles are secured in the corner areas of the upper and lower frames. The vertical frame profiles are symmetrical to the cross-sectional diagonals running across the virtual, vertical outer edges of the rack. Greater flexibility in installing built-in fixtures inside the switch cabinet is achieved by providing the vertical frame profiles which are turned towards the inside of the switching cabinet with an open inner cavity consisting of two inner walls extending in the longitudinal direction of the profiles so that vertical assembly rails can be mounted in the inner cavity, one profiled side standing perpendicular to the outside of the rack is joined to the inner walls, and the inner walls, the assembly racks and the profiled sides can be fitted with rows of fastening cavities inserted according to a division grid.

Description

DISTRIBUTION CABINET Description of the Invention The invention relates to a distribution cabinet comprising a frame of the frame provided with horizontal and vertical profiles of the frame. The horizontal profiles of the frame make up a lower frame and an upper frame and the vertical profiles of the frame are secured in the corner areas of the lower and upper frames. The vertical profiles of the frame are symmetrical to the diagonals of the cross section that extend through the virtual vertical external edges of the framework of the frame. The vertical profiles of the frame oriented towards the interior space of the distribution cabinet are provided with an open internal seat extending in the longitudinal direction of the profile, whereby vertical mounting rails can be inserted in the internal seat. One side of the profile that is perpendicular to the outside of the frame of the frame is attached to the inside walls, and the mounting rails are provided with rows of fixing housings made according to a dividing line. In the case of this known distribution cabinet, the framework of the frame is constituted by twelve equal frame profiles, which in each case meet each other orthogonally in the areas of the corners of the framework of the frame. The profiles of the frame have two internal walls that are aligned parallel to the associated sides of the frame of the frame. From these internal walls, angled sides of the profile extend at right angles to the side of the frame of the frame. With this, the internal walls and the sides of the profiles form a vertical inner edge oriented towards the interior space of the distribution cabinet. To the profiles of the frame, mounting rails can be fixed in the interior space of the distribution cabinet to hold embedded accessories. The mounting rails are configured as closed hollow profiles and have two support sides that are arranged at right angles to each other. The other two sides serve as mounting sides and are each provided with a row of fixing housings. The mounting rails can be supported with their support sides against the internal walls of the frame profile, where they can be connected, for example by welding or by screwing them. Both sides of assembly are then oriented towards the interior space of the distribution cabinet. The task of the invention consists in creating a distribution cabinet of the type under consideration that offers great versatility for the assembly of built-in accessories. This task is solved by proceeding in such a way that the inner walls and the sides of the profiles are provided with rows of fixing housings made according to a dividing frame. In its basic version without mounting rails, this distribution cabinet allows the mounting of recessed accessories in the fixing housings of the frame profiles. The use according to the invention of four rows of fixing housings offers great versatility for assembly. An internal wall and the side of the profile associated with it are always associated with the rear part or the front part of the distribution cabinet. The other internal wall with its profile side associated with it is always associated with the lateral part of the distribution cabinet. This structure allows associating the recessed accessories individually to the front, to the rear or to the side. For example, it is possible to fix wall elements parallel to a rear part to the internal walls and additionally to a side part, thereby to configure insulating walls or air conduction spaces. As a result of the use of rails The mounting versatility of the assembly can be further increased. In particular, it is possible to vary the structure of the row / rows of accommodation / fixing housings with respect to the profile of the frame with respect to its dividing frame. As a result, it is then possible to vary the mounting points discretely along the profile of the frame. The modification of the dividing screen also creates in a simple way the possibility of configuring a distribution cabinet with assembly measures combined according to the metric system and the English system. For example, the housings for fixing the profiles of the frame can be spaced apart from each other as measured in metric system, while those of the mounting rails are distanched according to measure in the English system .. In accordance with a preferred embodiment of the invention it is provided that sides of the profile of the vertical profiles of the frame are transformed into sealing surfaces extending parallel to the side surfaces of the frame of the frame. Against these surface sections of the profile, side walls, a rear wall and / or a cabinet door can be sealedly supported. By using such sealing surfaces a good sealing effect is achieved, in particular the positioning of HF seals is possible. . The lower frame and the upper frame can have open supports towards the external side of the frame of the frame in their corner areas, which are formed by the front sides of the horizontal frame profiles that meet against each other at right angles. The vertical profiles of the frame can be inserted into the supports. This is supported directly against the front sides of the horizontal frame profiles. Then it is not imperative to use a separate corner connector to connect the horizontal profiles of the frame and the vertical profiles of the frame to each other. The support of the vertical frame profiles against the front sides of the horizontal frame profiles is sufficient for a secure hold. To form an independent mounting unit it can be provided that at least the vertical profiles of the frame on one side of the frame of the frame are joined by connecting pieces to form a separate mounting unit. This stand-alone assembly unit can be equipped with electronic recessed accessories outside the frame frame and subsequently incorporated into the frame frame. The connecting pieces can for this purpose be configured as mounting rails having a mounting surface oriented towards the interior space of the distribution cabinet. Then, the mounting surface is conveniently provided with at least one row of fixing housings made with an identical spacing. To reduce the cost of parts, the lower and upper frames can preferably be structured identically. It is conceivable that the upper frame is configured with a leak (runoff channel) through which the water that runs off the upper part of the distribution cabinet can be evacuated in a controlled manner. To simplify the placement of the mounting rail in the internal seat of the vertical frame profile, it can be envisaged that the mounting rail has at least one wing of the profile with at least one plug-in support, by means of which it can be fitted onto a fastening element . The fastening element can for this purpose be placed in the vertical frame profile as an independent part. When the mounting rail is fitted on the fastening element, then the latter can be displaced with respect to the vertical profile of the frame to fix the mounting rail.

The invention will now be explained in more detail on the basis of the exemplary embodiments shown in the drawings. FIG. 1 shows, in a perspective elevation view, a frame frame for a distribution cabinet composed of profiles of the frame, FIG. 2 in the exploded view, a part of the framework of the frame, FIG. 3 a part of a frame, FIG. frame frame with an independent mounting unit, figure 4 a variant for positioning a vertical frame profile to horizontal frame profiles, figure 5 in perspective representation a vertical frame profile and a mounting rail, figure 6 two vertical frame profiles which are connected to each other via horizontal mounting rails, FIG. 7 a frame frame according to FIG. 2, with a side wall, and FIG. 8 a frame frame in accordance with FIG. Figure 2, with a cabinet door. Figure 1 shows a frame frame for a distribution cabinet. The frame frame is constituted essentially by a lower frame 10, an upper frame 10 and four vertical frame profiles 30. The vertical profiles 30 of the frame connect the lower frame 10 with the upper frame 10. The lower and upper frames 10 have the same structure, so that they can be exchanged with one another. The lower and upper frames 10 respectively have two horizontal frame profiles 11, 12 extending in the direction of the depth of the distribution cabinet and the width of the distribution cabinet. On their sides of the profile facing the inner space of the frame frame, these horizontal frame profiles 11, 12 are provided with rows of fixing housings 37. Threaded housings 37.1 are arranged between the individual fixing housings 37. Also the vertical frame profiles 30 are provided with fixing housings 37 and threaded housings 37.1 oriented towards the interior space of the framework of the frame. In mounting housings 37, it is possible to mount, for example, mounting rails like those shown in more detail in Figure 6. Vertical frame profiles 30 are connected to lower and upper frames 10 through parts 14 of Union. The connecting pieces 14 are arranged in the area of corner supports 20 of the lower and upper frames 10. The fastening of the vertical frame profiles 30 to the connecting pieces 14 is carried out, for example, by welding. Figure 2 shows an alternative fixation of the vertical frame profiles 30 to the horizontal frame profiles 11, 12. At the ends that run into each other of the horizontal frame profiles 11, 12, the supports 20 are formed. In the supports 20, the connecting pieces 14 are inserted. The connecting piece 14 has a substantially parallelepiped configuration. In one of its vertical ends it has however an oblique surface 19, in which one or more threaded housings 14.1 are made. The oblique surface 19 is oriented towards the outside of the frame frame. To fix the connecting piece 14, it is stopped on the base surface 20.1. With its support surfaces 16 facing the interior space of the switch cabinet, it rests against the front ends of the horizontal frame profiles 11, 12. In this position the connecting piece 14 can be welded inside the support. When this happens, the connecting piece 14 is arranged precisely at right angles to the associated horizontal frame profiles 11, 12. The front ends of the horizontal frame profiles 11, 12, as well as the base surface 24 form an open-out support for the front end of the vertical frame profile 30. The vertical frame profile 30 has an open internal seat 35.1 pointing towards the interior space of the frame of the frame. This internal 35.1 seat is limited by two walls 33, 34 interiors of vertical frame profile 30. The inner walls 33, 34 extend superficially in the longitudinal direction of the profile 30 of the frame. They are arranged at right angles to one another. With the vertical frame profile 30 mounted the inner walls 33, 34 rest against the stops 17, 18 of the connecting piece 14. At right angles to the inner walls 33, 34, profile sides 31, 32 are joined to the vertical frame profile 30. These sides 31, 32 of the profile come to rest against the front ends of the horizontal frame profiles 11, 12. For fastening the vertical frame profiles 30, in each case one or more screw housings 38 are drilled in the area of their front ends. These screw housings 38 can be arranged aligned with respect to the threaded housings 14.1 of the connecting piece 14. In order to simplify assembly, the distance from the front end of the frame profile 30 to the piercing center of the screw housing 38 is adjusted to the distance of the base surface 24 from the threaded housing 14.1. A fastening screw 39 can be inserted through the screw housing 38 and screwed into the threaded housing 19 of the connecting piece 14. By this, the inner walls 31, 34 are clamped against the stops 17 and 18 of the connecting piece 14. Simultaneously the vertical frame profile 30 is pulled into the support 20 at the front ends of the horizontal frame profiles 11, 12. In its final assembly position, the vertical frame profile 30 is fixedly attached to the connecting piece 14, and is vertically aligned with precision. The drawing clarifies that the vertical frame profile 30 can be inserted into the support 20 from the outer side of the frame of the frame. That is to say, the vertical frame profiles 30 can also be removed and subsequently placed in the case that the framework of the frame is already fully assembled. This results in the definite advantage that the interior space of the frame frame is easily accessible. For example, an independently self-supporting unit comprising the lower and upper frames 10 and the two vertical rear frame profiles 30 can be assembled. This partially independent self-supporting frame frame can then be equipped with electronic recessed accessories or the like. Subsequently, the two front vertical frame profiles 40 can be mounted, so that the framework of the frame is completed. In figure 3 a part of the framework of the frame is shown. In this case, both vertical frame profiles 30 on one side of the frame frame are joined in a mounting unit by joining pieces 40. In the present case, both connecting pieces 40 are configured as mounting rails. These mounting rails are formed with a U-shaped cross section by a mounting surface 41 and two lateral parts 42, 43 adjacent to it. The lateral parts 42, 43 are parallel with respect to each other. The mounting surface 41 is offset to the interior space of the frame of the frame. A fastening section 45 is attached laterally to the mounting surface 41 in each case on the front side. The fastening section 45 is configured as a lobe that partially overlaps the associated interior wall 34 of the vertical frame profile. As indicated in the drawing, the connecting piece 40 can be screwed with the vertical frame profiles 30 through the fastening section 45. Electronic operation units can be immobilized. For this purpose, fixing housings 44a, 44b are made in the mounting surfaces 41 and the lateral parts 42, 43. The fixing housings 44a, 44b are arranged in lines and have a uniform division distance with respect to each other. The division distance is adjusted to the division distance of the fixing housings 37 of the vertical frame wings. In the case of the mounting unit shown in the drawing, connecting pieces 40 are provided in the upper and lower areas of the vertical frame profiles 30. Nevertheless, it is also possible to use more than two joining pieces 40 to form the assembly unit. In particular it is also possible to use cross braces, which are placed inclined between both vertical wings of the frame. To assemble the mounting unit to the lower unit 10, it is pushed into the supports 20 in its vertical standing position. When this happens first the vertical wings 30 of the frame with their front sides 36 against the base surface 24 of the lower frame 10 are seated. The entire assembly unit is then pushed into the support 20 against the direction of the arrows shown in the drawing. When this happens, the interior walls 34 of the vertical frame profiles 30 slide along the associated stops 18 of the corner joining piece 14. These stops 18 now serve as guides. The insertion movement is limited to the sides 32 of the profile of the vertical frame profiles 30. These sides come to rest against the front sides of the horizontal frame profiles 11. Simultaneously the inner wall 34 abuts against the stop 17 of the connecting piece 14. Between both stops 17 and 18 of the corner joining piece 14 there is provided an inclined flank 19. This protrudes into the interior of the inner seat 35.1 of the vertical frame profiles 30. A free space is formed between the flank 19 and the floor surface of the inner seat 35.1. With this free space it is ensured that the vertical frame profiles 30 always rest only with their inner walls 33, 34 against the stops 17, 18. This allows to precisely align the mounting unit in the lower unit 10. For fixing, the mounting unit is screwed with the lower frame 10. The type of screwing of the vertical frame profiles 30 with the corner joining pieces 40 is apparent from FIG. 2. However, it is also possible to directly weld the vertical frame profiles 30 with the lower frame 10 and the connecting piece 14. corner In addition to the lower frame 10, the upper frame 10 is used, which will preferably be of the same construction. The upper frame 10 is attached to the vertical frame profiles 30 in the upper area. The frame frame can then be completed with other vertical frame profiles 30. The assembly unit is conveniently arranged in the rear of the distribution cabinet. However, it is also possible to arrange the mounting unit on a side part of the frame of the frame. A multitude of fixing possibilities are available for the assembly unit. In particular, the inner walls 33, 34 and the sides 31, 32 of the profile associated to one another by pairs of the vertical frame profiles 30 can be used to form two mounting planes displaced parallel to one another. In the drawing the first mounting plane is partially formed by the mounting surfaces 41 of the joining pieces 40. It is also possible to make such mounting planes displaced perpendicularly to the mounting unit in the framework of the frame. For this purpose, the fixing housings 37, 37.1 of the inner walls 33 and of the sides 31 of the profile are used. In order to avoid a risk of injury, on the base surfaces 24 of the supports 20 it is provided with a profiling 21. Here, the profiling 21 adapts to the external geometry of the vertical frame profiles 30. With this, the edges of the lower unit do not protrude from the vertical frame profiles. Figure 4 shows a section of a lower frame 10 which is composed of horizontal frame profiles 11, 12. The cross section of the horizontal frame profiles 11, 12 has the same geometry. The entire lower frame 10 is composed of four horizontal frame profiles 11, 12, as can be seen in advance from figure 1. For manufacturing the lower frame 10, a single bent and stamped piece can be used, so that the individual horizontal frame profiles 11, 12 are connected to one another in a single piece. The horizontal frame profiles 11, 12 have a horizontal inner wall 25 abutting a fold 26 downwards that encloses an angle of 90 °. The fold 26 serves as a support for a side wall 63 (for example according to FIG. 7) or for a door 72 of the cabinet (for example according to FIG. 8). For sealing purposes, a sealing element can be inserted between the side wall 63 or the door 72 of the cabinet and the folding 26. From the folding 26 a horizontal flange 27.1 is bent at a right angle backwards. This flange 27.1 is transformed to become the wall 27 directed downwards. In the free space formed for the flange 27.1 and the wall 27, a folding of the side wall 63 or the door 72 of the cabinet can be accommodated. The wall is closed with a floor part 28. Here the lower frame 10 can be placed on the floor. At the front ends the horizontal frame profiles 11, 12 are provided with the profiling 21 in their flanges 27.1. Again in this case the profiling 21 is adapted to the external geometry of the vertical frame profile 30. Widened in the vertical direction of the flange 27.1, in the inner walls 25 are provided at the ends stops 22, 23 for the vertical frame profile 30. In the support 20, the connecting piece 14 is stopped. In this, the joining piece 14 is stopped on the bottom part 28. It laterally rests against the walls 27. The horizontal frame profiles 11, 12 can be connected to the connecting piece 14, for example by welding. This serves to provide rigidity to the lower / upper frame 10. The vertical frame profile 30 has an external housing 35.2 configured as a wall, which points towards the external lateral part of the frame of the frame. On both sides of the wall, two hollow chambers extend. To form the hollow chambers, the sheet metal cutout for the vertical frame profile is folded several times. Individually adjoins with the wall a centering section 30.1, which becomes an angle 30.3 through a transition piece 30.2. In this the angle 30.3 is arranged vertically with respect to the associated sides of the framework of the frame. The sealing surfaces 30.4 are connected at right angles to the angles 30.3. For the formation of the sides 31, 32 of the profile, the sealing surfaces 30.4 are bent at right angles towards the interior space of the framework of the frame. The sides 31, 32 of the profile become the interior walls 33, 34 passing through a right angle. In this way the inner walls 33, 34 are parallel to the associated sides of the frame of the frame. Through bent end pieces, the inner walls 33, 34 rest against the wall forming the outer housing 35.2. Between the two inner walls 33, 34 the internal seat 35.1 is created which is oriented towards the interior space of the framework of the frame. The vertical frame profile 30 is inserted into the support 20 open outwardly of the lower frame 10. When this happens, the sides 31, 32 of the profile slide along the stops 22, 23 of the horizontal frame profiles 11, 12. With its front side 36 the vertical frame profile 30 bears with the front side on the base surface 24 of the lower frame 10. In this position the vertical frame profile 30 is aligned by its sides 31, 32 of the profile. With this also the inner walls 33, 34 are positioned oriented towards the interior space of the framework of the frame. The exact vertical alignment of the profile 30 of the frame is possible with the profiling 21. As it adapts to the external geometry of the profile 30 of vertical frame, can be supported here flush. In Figure 5 it is shown in more detail how a mounting rail 50 can be mounted to one of the vertical frame profiles 30. From the vertical frame profile 30 only a part is shown in the drawing according to FIG. 5. The mounting rail 50 has a length corresponding to that of this part. With this representation it becomes clear that the mounting rail 50 can be applied by sections in points at discretion along the horizontal frame profile. Of course, the length of the mounting rails 50 that are used can also be varied. In particular, they can also extend along the entire axial length of the vertical frame profiles 30. The mounting rail 50 has a square cross-sectional structure. This cross section is formed by two mounting sections 52, 53 connected at right angles and two profile sections 51, 54. The profile sections 51, 54 are folded in each case from the free ends of the mounting sections 52, 53. In this way a hollow profile is formed which is open in the area between sections 51, 54 of the profile. Fitting housings 56, 57 are made in the mounting sections 52, 53. On the sides 51, 54 of the profile, fixing holes 55, 58 are punched. The mounting housings 56, 57 and the fixing holes 55, 58 are arranged spaced apart from each other in equal division. The fixing holes 55, 58 for this are arranged so that they are aligned with a mounting housing 56, 57 of the mounting section that is parallel to the respective section of the profile. That is, access holes 55, 58 are accessible through the mounting housings 56, 57. To fix the mounting rail 50 to the vertical frame profile 30, insertion housings 59 are drilled in the sides 51, 54 of the profile. The insert housings 59 have a slot configuration and are open towards the free vertical end of the sections 51, 54 of the profile. In the present case, an insert housing 59 is used for each section 51, 54 of the profile. To immobilize the mounting rail 50, a holding element 39.1 is first screwed into a threaded housing 37.1 of the vertical frame profile 30. It is possible to select at which discretion in which of the inner walls 33, 34 of the frame profile 30 the fastening element 39.1 (hereinafter referred to as screw) is screwed, and this will depend essentially on accessibility. The mounting rail 50 engages with its housing 59 for inserting section 54 of the profile onto the bolt section of the screw. This insertion movement is symbolized by the representation of the arrow in figure 5. When the mounting rail 50 is thus mounted to the frame profile 30, it is pre-positioned. At the head of the screw there is access via a tool through a mounting housing 56 of the mounting section 52 arranged in alignment with the insert housing 59. If the screw is still turned inwardly in the threaded housing 39.1, then the head of the screw is deformed on the section 51 of the profile. The mounting rail 50 is pulled into the inner seat 35.1 of the profile 30 of the frame. Then both sections 51, 54 of the profile rest against the inner walls 33, 34. The mounting rail 50 is precisely aligned with the profile 30 of the frame. For additional fastening, screws can be passed through the individual mounting housings 56, 57, inserted into the fixing holes 55, 58 and screwed into the respectively associated threaded housings 37.1. Depending on the type and size of the load to which the mounting rail 50 is subjected, one or more additional fastening elements 39.1 may be used. Figure 6 shows how mounting rails 40 can be mounted to two vertical frame profiles 30. The mounting rails 40 substantially correspond to the mounting rails 40 as shown in figure 3. Here we want to clarify once again how two different mounting planes can be configured arranged parallel to one another in the frame profiles 30. The assembly plans are created by the mounting surfaces 41 of the mounting rails 40, as already mentioned. Figure 7 shows how fastening elements 60 can be mounted on the outer seat 35.2 of the vertical frame profiles 30. The fastening elements 60 have two fastening points with screw holes 61 threaded. For the placement of side walls 63 screws 62 are used. These screws 62 are inserted through holes in the side walls 63 and screwed into the screw holes 61 of the fastening elements 60. In doing so, the side wall 63 is supported with its inner side sealing against the sealing surface 30.4 of the vertical frame profile 30. The fastening elements 60 shown in FIG. 7 can be used to fix two side walls 63 which are enclosing a right angle between them to the frame frame. In figure 8 it is shown how hinged parts 70 can be attached to the external seat 35.2. To mount a door 72 of the cabinet in hinges, other hinge parts 76 are mounted on the door leaf. These other hinge parts 76 can be attached to the hinge parts 70. On the inner wall of the door 72 of the cabinet a gasket 74 is placed. The seal gasket 74 rests on the sealing surface 30.2 sealing the vertical frame profiles 30. The representation according to FIG. 8 makes it possible to recognize that the part 70 of the hinge in a fixing to the side wall has a threaded bore 71. That is, a side wall at right angles to the front of the frame frame can be fixed to the hinge part 70.

Claims (5)

1. CLAIMS Distribution cabinet comprising a frame of the frame provided with horizontal and vertical profiles of the frame, the horizontal profiles of the frame forming a lower frame and an upper frame, the vertical profiles of the frame being secured in the areas of the frames. corners of the lower and upper frames and that the vertical profiles of the frame are symmetrical to the diagonals of the cross section that extend through the virtual vertical external edges of the framework of the frame, being that the vertical profiles of the frame oriented towards the interior space of the distribution cabinet are provided with an open internal seat that extends in the longitudinal direction of the profile, being that in the internal seat can be inserted vertical mounting rails, being that the interior walls is joined in each case a side of the profile that is perpendicular to the external side of the frame of the frame, and the mounting rails being provided with rows of fixing housings made according to a dividing frame, characterized by the fact that the interior walls and the sides of the profiles are provided with rows of Fixation housings made according to a dividing plot. Distribution cabinet according to claim 1, characterized in that the vertical frame profiles are transformed on their sides of the profile into sealing surfaces extending parallel to the lateral surfaces of the framework of the frame. Distribution cabinet according to claim 1 or 2, characterized in that in its corner areas the lower frame and the upper frame have open supports towards the external part of the frame of the frame, the supports being formed by the sides Frontal surfaces that meet against each other at right angles to the horizontal frame profiles. Dispensing cabinet according to claim 3, characterized in that corner joining pieces are inserted into the supports of the lower and upper frames, and because the vertical frame profiles can be pushed horizontally into the supports and can be immobilized against the corner joining pieces. Distribution cabinet according to one of claims 1 to 4, characterized in that the vertical frame profiles are provided with an external seat that extends in the longitudinal direction of the profile, because the external seat is formed by a wall that is it is perpendicular to the diagonals of the cross section that extend through the virtual external edges of the framework of the frame, and because two centering sections of the vertical frame profile are joined to the wall. Distribution cabinet according to one of claims 1 to 5, characterized in that at least the vertical frame profiles on one side of the frame of the frame are joined together by joining pieces to form a separate assembly unit. Distribution cabinet according to claim 6, characterized in that the connection parts are configured as mounting rails having a mounting surface oriented towards the interior space of the distribution cabinet, and because the mounting surface is provided with at least one row of fixing housings made with equal separation. Distribution cabinet according to one of claims 1 to 7, characterized in that the lower frame and the upper frame are configured as equal groups. Distribution cabinet according to one of claims 1 to 8, characterized in that the mounting rail that can be locked in the internal seat of the vertical frame profile has at least one profile wing with at least one insertion housing through which it can be fitted on the fastening element that is mounted on the vertical frame profile, and in that the fastening element can be moved with respect to the vertical frame profile to fix the mounting rail. Distribution cabinet according to one of claims 1 to 9, characterized in that the lower frame and / or the upper frame are provided with a surrounding leak only interrupted in the corner areas of the frame of the frame.