Abstract:
A frame piece for a rack of a switching cabinet. With minimum material an optimum result is obtained with regard to fastening planes and fastening direction as well as stability. A profile inside and a profile outside are used to form the frame piece as a closed hollow profile with one or two longitudinally directed hollow spaces. The profile outside delineates a free space to an outside corner edge of the rack. The profile inside has a profile section with several rows of fastening seats or several profile sections at an angle with respect to one another with at least one series of fastening seats. The profile inside and the profile outside form outside edges in a region of the right-angled abutting outsides of the rack. The outside edges are designed as double-layer sealing struts or connected to them in a direction to the outside corner edge connecting struts with or without receiving grooves for sealing elements.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a frame piece for a switching cabinet. 
     2. Description of Prior Art 
     Greatly varied requirements are set for a rack for a switching cabinet and these requirements must be fulfilled by all the cross-sectional shapes of the frame pieces used. In an area of the bottom frame or the top frame, one can use frame pieces which have a cross-sectional form different from the vertical frame piece. Especially for the frame pieces which are in the vertical direction of the rack, as many fastening possibilities as possible are required in several directions. Moreover, with as low material expenditure for the frame piece as possible, optimum strength, preferably strength to deformation, and yet simple manufacture of the frame piece should be possible. Moreover, in the region of the vertical outside corner edges of the rack, sufficient free space should be available to apply the hinge for a cabinet door and to form an introduced sealing element for the side walls to be introduced or for the back wall of the cabinet. 
     Many frame pieces are known for the rack of a switching cabinet, which partly fulfill the requirements named above, but do not offer satisfactory solution in all respects. Frame pieces designed as open hollow profile sections are considerably worse than closed hollow profile sections. 
     SUMMARY OF THE INVENTION 
     It is one object of this invention to provide a frame piece for a rack of a switching cabinet which, particularly when used as vertical frame piece, fulfills sufficiently requirements for high strength for universal possibilities of fastening with low material expenditure and simple manufacture. 
     This object is solved by the following characteristics: 
     a) With a profile inside and a profile outside, the frame piece forms a closed hollow profile with one or two longitudinally directed hollow spaces; 
     b) the profile outside delineates a free space to the outside corner edge of the rack; 
     c) the profile inside has a profile section with several rows of fastening seats or several profile sections at an angle to one another with at least one series of fastening seats; and 
     d) the profile inside and the profile outside form outside edges in a region of the right-angled abutting outsides of the rack, wherein the outside edges are designed as double-layer sealing struts or are connected in a direction to an outside corner edge connecting struts with or without receiving grooves for sealing elements. 
     The free space to the outside corner edge delineated by the profile sides of the profile outside offers sufficient clearance for swinging a cabinet door as well as to introduce beveled paneling elements at the frame piece. The sealing struts, connecting struts and/or receiving grooves in the connecting struts of the profile outside offer many possible variations. The closed hollow profile of the frame piece with one or two hollow spaces has very good stability, especially deformation strength, which can also be used to minimize the material expenditure for the frame piece, especially when the frame piece is stamped from a strip, is bent and is assembled. 
     According to one embodiment, the free space is delineated at least in partial regions starting from the outside of the rack by profile sides of the profile outside standing perpendicularly to the facing outsides. Thus, even with a small distance between the outside edges of the frame piece and the outside corner edge of the rack, a sufficiently large inlet opening into the free space is created. 
     In one preferred embodiment the profile sides of the profile outside delineating the free space are connected through a connecting section with one another and/or with the profile inside, and the free space is thus delineated in its depth in the region of the rack diagonal and the connecting section of the profile outside increases the deformation strength of the frame piece. The possibilities of fastening on the frame piece can be increased in the area of the outside of the profile also, by providing additional fastening seats in the connecting section. 
     The profile inside is a profiled side guided from outside edge to outside edge, which has fastening seats in a mirror-image manner to the rack diagonal. A greater flexibility with regard to the fastening planes and directions is achieved by the profile inside being formed from three profile sides arranged in a U-shape, where the profile sides starting from the outsides of the rack and thus from the outside edges, at an angle of 45° to the outside edges. In this case, the third profile side, which is perpendicular to the two profile sides of the profile inside have fastening seats in a mirror-image manner to the rack diagonal. The profile sides of the profile outside that stand perpendicular to the outsides of the rack can be connected directly to the profile inside. In this case, the profile inside and the profile outside enclose two identical hollow spaces, which can be designed so that a cross-section is an equilateral triangle or an isosceles rectangular triangle. 
     However, the direction of the profile sides of the profile inside and profile outside can also be arranged so that the profile inside and the profile outside enclose two identical hollow spaces which have an essentially square or rectangular cross section. 
     According to another embodiment, for reasons of stability, two profile sides of the profile inside are each arranged in one plane with a profile side of the profile outside whereby the planes are perpendicular to one another and perpendicular to the outsides of the rack. 
     The stiffening of the profile inside can be simply achieved by connecting the profile sides of the profile inside facing the rack diagonal through a connecting section running perpendicular to the diagonal of the rack. The connecting section of the profile inside can be used as a result of this as an additional fastening plane, by providing the connecting section of the profile inside with additional fastening seats. 
     If the profile inside and the profile outside enclose a single hollow space which has mirror-image symmetry with respect to the rack diagonal, then the profile inside and the profile outside are at a distance and can be optimally designed for and dictated by stability of the frame piece. 
     If the profile outside of the frame piece has a connecting section, then this can also carry fastening seats which make it possible to attach parts to the outside of the profile. 
     According to one embodiment, the profile sides of the profile inside and/or the profile sides of the profile outside form an open, undercut recess, which is open toward the inner space of the rack and/or to the outside corner edge and which facilitates the incorporation of mounting tracks and similar. 
     In one preferred embodiment, there is mirror-image symmetry with respect to the rack diagonal, because the incorporation of the frame piece into the rack is facilitated. The ends of the frame piece can then be interchanged. 
     The frame piece can be easily produced as a section of an extruded profile. 
     According to another manufacturing method, the frame piece is produced as a stamped-bent part, the point of impact and point of connection of which is placed in the area of a connecting section of the profile inside or profile outside. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     This invention will be explained in more detail in view of six different practical examples of a frame piece shown in cross-section, in FIGS.  1 - 6 . 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     In all practical examples, AS 1  and AS 2  designate the two outsides of a rack meeting at a right angle, and the rack diagonal RGD is shown as the angle bisector. The two outsides, AS 1  and AS 2 , form an outside corner edge AEK, but this does not adversely affect the frame piece with its profile outside  20  and allows sufficient free space FR. The profile outside  20  and the profile inside  10  are, however, preferably, not necessarily arranged in a mirror-image manner to the diagonal of the rack RGD and form outside edges AK 1  and AK 2  on outsides AS 1  and AS 2 . If the profile inside  10  and the profile outside  20  are outside outer edges AK 1  and AK 2 , preferably, connected to one another in the region of the rack diagonal RGD, then the frame piece encloses two hollow spaces H 1  and H 2 , which can be designed so that they have a cross-section as right-angled isoceles or right-angled equilateral triangles, as shown in the practical examples according to FIGS. 1 to  3 . The hollow spaces H 1  and H 2  may also have an essentially square or rectangular cross-section as shown in the practical examples according to FIGS. 4 and 5. 
     When the profile inside  10  and the profile outside  20  are not joined together between the outside edges AK 1  and AK 2 , then they enclose a single hollow space H, as shown in FIGS. 5 and 6. This hollow space H preferably, but not necessarily, has a cross-section which is arranged in a mirror-image manner to the rack diagonal RGD. 
     In the practical example according to FIG. 1, the profile inside  10  is designed as a profile side extending all the way from outside edge AK 1  to outside edge AK 2  and is at an angle of 45° to the joining profile sides of profile outside  20 , which coincide with the outsides AS 1  and AS 2  of the rack, as connecting sections  21  and  22 . The connecting sections  21  and  22  of the profile outside  20  continue into profile sides  23  and  25 , which are perpendicular to the facing outsides AS 1  and AS 2  of the rack. The hollow spaces H 1  and H 2  have an isosceles right-angled triangular cross-section and the free space FR has a square cross-section with a side length determined with the width of profile sides  23  and  24 . The profile inside  10  has two sections  11  and  13  which lie in a plane. Sections  11  and  13  have at least one row of fastening seats  12  and  14 , which are arranged symmetrically to rack diagonal RGD in sections  11  and  13  of profile inside  10 . 
     In the practical example according to FIG. 2, the profile outside  20  comprises the two profile sides  23  and  24  standing perpendicularly to the outsides AS 1  and AS 2  of the rack facing them. On these profile sides  23  and  24 , the outside edges AK 1  and AK 2  continue on profile sides  11  and  13  of the profile inside  10 , and are at an angle of 45° to the profile sides  23  and  24  of profile outside  20 , so that automatically outside edges AK 1  and AK 2  are produced which can be used as sealing struts to the outsides AS 1  and AS 2 . The profile sides  11  and  13  of the profile inside  10  are connected to one another through the profile side constructed of sections  15  and  17 . The sections  15  and  17  are at a right angle to the profile sides  11  and  13  and are connected with the profile sides  23  and  24  of the profile outside  20  in the region of the rack diagonal RGD. The hollow spaces H 1  and H 2  have a right-angled isosceles cross-section but by arranging the profile sides  11 ,  15  and  23 , and  13 ,  17  and  24 , differently, can also have an equilateral cross-section, in which case the profile sides always meet at an angle of 60°. The perpendicular arrangement of the profile sides  23  and  24  to the outside AS 1  and AS 2  of the rack can be maintained. The profile sides  11 ,  13 ,  15  and  17  of the profile inside  10  have at least one row of fastening seats  12 ,  14 ,  16  and  18 , which are preferably arranged in a mirror-image manner to the rack diagonal RGD. The distribution of the fastening seats can also be different with regard to design, direction and distribution in the profile sides, without giving up the mirror-image cross-section with regard to the rack diagonal RGD. 
     As shown in FIG. 3, with the same distance of the outside edges AK 1  and AK 2  to the outside corner edge AEK of the frame piece, they coincide with the outsides AS 1  and AS 2  only in the region of the outside edges AK 1  and AK 2 . In this case, with sections  31  and  32 , the ends of the profile sides  23  and  24  of the profile outside  20  are designed as a double-layer sealing struts DS 1  and DS 2 . Profile sides  11  and  13  of the profile inside  10  join to sections  31  and  32 , running parallel to the rack diagonal RGD and continuing in the profile sides  15  and  17  of profile inside  10 , which meet profile sides  23  and  24  at a right angle and lie with these in two planes perpendicular to the outsides AS 1  and AS 2 . The profile sides  15 ,  17 ,  23  and  24  are connected to one another in the region of the frame diagonal RGD. The hollow spaces H 1  and H 2  have an isosceles right-angled cross-section and are arranged in a mirror-image manner to the rack diagonal RGD. The profile sides  11 ,  13 ,  15  and  17  have at least one row of fastening seats  12 ,  14 ,  16  and  18 . 
     In the practical example according to FIG. 4, the connecting struts  21  and  22  of the profile outside  20  lie on the outsides AS 1  and AS 2  but have one fastening groove  26  and  27 , respectively, for a sealing element. The connecting sections  21  and  22  continue into profile sides  23  and  24 , which are perpendicular to the outsides AS 1  and AS 2  of the rack facing them. The profile sides  23  and  24  do not reach all the way to the rack diagonal RGD, but are connected together through a connecting section  25  which is directed perpendicularly to the rack diagonal RGD and is connected with a connecting section  19  of the profile inside  10  directed in the same direction. This connecting section  19  of the profile inside  10  connects the profile sides  15  and  17  of the profile inside  10  which run parallel to the outsides AS 1  and AS 2  of the rack. The profile sides  15  and  17  continue in profile sides  11  and  13  in the outside edges AK 1  and AK 2  of the frame piece. The profile sides  11  and  13  of the profile inside  10  are perpendicular to the outsides AS 1  and AS 2  facing them. The hollow spaces H 1  and H 2  have an essentially square cross-section but can also be rectangular. The profile sides  11 ,  13 ,  15  and  17  have at least one row of fastening seats  12 ,  14 ,  16  and  18 . The frame piece is designed so that it shows mirror-image symmetry with respect to the rack diagonal RGD. 
     FIG. 4 shows a first practical example of a frame piece with a single hollow space H arranged in a mirror-image manner to the rack diagonal RGD. Here, the profile sides  11  and  13  with the rows of fastening seats  12  and  14  start from outer edges AK 1  and AK 2  and form with the continuing profile sides  15  and  17  with their fastening means  16  and  18  a receptacle which is open to the inside of the rack and has a mirror-image symmetry with respect to the rack diagonal RGD. The profile sides  11  and  13  continue directly into one another on the rack diagonal RGD and are at a distance to the connecting section  25  of the profile outside  20 . The connecting section  25  reduces the depth of the free space FR in the region of the rack diagonal RGD. In this practical example of a frame piece, the profile sides of the profile outside  20  are designed as connecting sections  21  and  22  and have fastening seats  28  and  29 . The profile sides  11  and  15 , and  13  and  17 , which are at a right angle to one another, can also be not at a right angle and not parallel to the outsides AS 1  and AS 2  of the rack, whereupon a single hollow space H remains which shows mirror-image symmetry with respect to the rack diagonal RGD. The receptacles formed by the profile sides  15  and  17  of the profile inside  10  and by the profile sides  23  and  24  as well as by the connecting section  25  can be designed so that they are undercut. These receptacles are open towards the inner space of the rack and toward the outer corner edge AEK. 
     In the practical example according to FIG. 6, profiles sides  11  and  13  of the profile inside  10  are connected to one another through a connecting section  19 , which runs parallel to the connecting section  25  of the profile outside  20  and is arranged at a distance from the connecting section  25 . The connecting sections  19  and  25  have fastening seats  33  and  34 . At least the profile sides  11  and  13  of the profile inside  10  have fastening seats  12  and  14 . The connecting sections  21  and  22  of the profile outside  20  can have receiving grooves for sealing elements instead of the fastening seats  28  and  29 . 
     The profile sides  11 ,  13 ,  15  and  17  of the profile inside  10  and the profile sides  23  and  24  of the profile outside  20  of the frame piece according to FIGS. 5 and 6 can also meet inclined at different angles and yet a single hollow space H, which shows mirror-image symmetry with respect to the rack diagonal RGD, can be maintained.