Abstract:
The invention relates to a method for producing a sheet metal profile, in particular consisting of steel, for a drawer pull-out guide having at least one web projecting laterally, in particular perpendicularly, from a flat surface of the sheet metal profile and extending in the longitudinal direction of the sheet metal profile, wherein, in a first method step, from at least one flat surface of a sheet metal billet there is extruded at least one web projecting laterally, in particular perpendicularly and extending in the longitudinal direction of the sheet metal billet, and in at least one further method step, preferably in 10 to 15 further method steps, the at least one web is squeezed together, i.e. is reduced in width and increased in height. The invention further relates to a sheet metal profile produced in this manner and to a drawer pull-out guide that comprises such a profile.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The invention concerns a method for producing a sheet metal profile, in particular consisting of steel, for a drawer extension guide having at least one web projecting laterally, in particular perpendicularly, from a flat surface of the sheet metal profile and extending in the longitudinal direction of the sheet metal profile. The invention further concerns a sheet metal profile produced by the method and a drawer extension guide including at least one sheet metal profile produced by the method. 
         [0002]    Such a production method—although not explicitly directed to the production of a sheet metal profile for a drawer extension guide—is known by the term “gap profiling”, which is subject-matter of DE 100 39 768 A1, wherein that method involves using a shaping roll engaging the edge of a piece of sheet metal to shape out of the edge of the piece of sheet metal at least one flange facing away from the plane of the piece of sheet metal and of smaller thickness than the thickness of the initial workpiece. The flange produced in that way can then subsequently be further deformed relative to the initial sheet metal (compare DE 103 05 542 A1). 
         [0003]    A disadvantage with the method known from the state of the art is that the flange on the one hand can only be shaped out of the edge of the sheet metal and on the other hand the flange is of a thickness which is smaller in comparison with the initial sheet metal. That means that the method is unsuitable for a series of areas of application, for example drawer extension guides. 
       SUMMARY OF THE INVENTION 
       [0004]    The object of the invention is to avoid the above-described disadvantages and to provide a method which is improved over the state of the art as well as a sheet metal profile produced by that method and a drawer extension guide including at least one such sheet metal profile. 
         [0005]    To attain that object it is provided according to the invention that
       a first method step comprises squeezing out of at least one flat surface of an elongate sheet metal profile at least one web projecting laterally, in particular perpendicularly and extending in the longitudinal direction of the elongate sheet metal portion, and   the at least one web is squeezed together in at least one further method step, preferably in between 10 and 15 further method steps, that is to say it is reduced in its width and increased in its height.       
 
         [0008]    In comparison with the state of the art it is possible by virtue of that method to produce the at least one web in any region of a flat surface of an elongate sheet metal portion, that is to say not just in the edge region, and at the same time—depending on how far the at least one web is squeezed together in the further method steps—to make the web of any desired dimension, that is to say to adapt the parameters of width and height of the web to its specific purpose of use. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    Advantageous embodiments of the invention are defined in the appendant claims and are described more fully hereinafter together with further details and advantages of the invention in the context of the following description of the Figures in which: 
           [0010]      FIG. 1  shows a diagrammatic perspective overall view of an embodiment of the production method according to the invention, 
           [0011]      FIGS. 2   a )  2   b ),  2   c ),  2   d ),  2   e ),  2   f ),  2   g ),  2   h ),  2   i ),  2   j ), and  2   k ) are schematic diagrams showing a succession of diagrammatically illustrated cross-sectional views of the cross-sectional planes I through XI indicated in  FIG. 1 , in which the elongate sheet metal portion has been omitted in the cross-sectional views of  FIGS. 2   b ),  2   d ),  2   f ),  2   h ) and  2   j ), 
           [0012]      FIGS. 3   a )  3   b ),  3   c ),  3   d ), and  3   e ) are enlarged diagrammatic cross-sectional views of the cross-sectional planes II, IV, VI, VIII and X indicated in  FIG. 1 , 
           [0013]      FIG. 4  shows a diagrammatically illustrated cross-section of a possible embodiment of a drawer extension guide, 
           [0014]      FIGS. 5   a ) and  5   b ) show an embodiment of a sheet metal profile according to the invention which can be used as a carcass rail in a drawer extension guide,  FIG. 5   a ) showing a perspective view and  5   b ) showing a cross-sectional view, 
           [0015]      FIGS. 6   a ) and  6   b ) show a further embodiment of the sheet metal profile according to the invention which can be used as a central rail in a drawer extension guide,  FIG. 6   a ) showing a perspective overall view and  FIG. 6   b ) showing an enlarged view of a portion thereof, and 
           [0016]      FIGS. 7   a ) and  7   b ) show a profiling roll used in the method according to a preferred embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0017]      FIG. 1  diagrammatically shows a perspective view of an embodiment of the production method according to the invention. An elongate sheet metal portion  6  which includes a flat surface  3  is processed in five method steps by means of shaping apparatuses in the form of profiling roll sets  10 ,  11 ,  12 ,  13  and  14 . In this connection a man skilled in the art in connection with processing by profiling rolls also uses the term “passes”. In the illustrated case the elongate sheet metal portion  6  is consequently processed in five successive passes. In that situation the elongate sheet metal portion  6  is moved along its longitudinal direction  4  through the shaping apparatuses  10 ,  11 ,  12 ,  13  and  14 . The direction of movement is identified by means of an arrow. 
         [0018]    In the illustrated example the elongate sheet metal portion  6  admittedly includes only one flat surface  3  but in preferred embodiments it can also be the case that an elongate sheet metal portion which has already been partially shaped is fed to the shaping apparatuses and/or the elongate sheet metal portion subsequently to the processing operation is further shaped, preferably bent. 
         [0019]    At least one first and at least one further method step are required for carrying out the method. In the illustrated example, as already stated, five method steps are shown. Preferably, besides a first method step, between ten and fifteen further method steps take place. For the sake of simplicity however that preferred embodiment is not illustrated here. 
         [0020]      FIGS. 2   a ) through  2   k ) and  FIGS. 3   a ) through  3   e ) serve to illustrate the individual method steps, wherein those Figures respectively show a given cross-section indicated by means of dash-dotted lines from the structure shown in  FIG. 1 . 
         [0021]    To start with, the basic structure of the shaping apparatuses  10 ,  11 ,  12 ,  13  and  14  which are preferably used will also be briefly considered: each of those shaping apparatuses  10 ,  11 ,  12 ,  13  and  14  includes a profiling roll set having a first profiling roll  15  and two further profiling rolls  16  and  17 . Each of those profiling rolls  15 ,  16  and  17  is substantially in the form of a cylinder having a peripheral surface  15 ,  26  and  27  respectively and two end faces which in the case of the two further profiling rolls are denoted by references  28  and  29 . Further details like for example the relative spatial arrangement of the profiling rolls  15 ,  16  and  17  with respect to each other will be discussed more fully in the course of the description of  FIGS. 3   a ) through  3   e ). 
         [0022]    The sequence of  FIGS. 2   a ) through  2   k ) serves to illustrate the method steps shown in  FIG. 1 , wherein the Figures correspond in the alphabetical sequence to the cross-sectional planes in  FIG. 1 , identified by Roman numerals I through XI, in which respect it is to be added that the sheet metal profile  6  has been omitted from  FIGS. 2   b ),  2   d ),  2   f ),  2   h ) and  2   j ) for the sake of simplicity. Those five cross-sectional views are described more fully with reference to  FIGS. 3   a ) through  3   e ). 
         [0023]    The starting point of the method is the elongate sheet metal portion  6  having at least one flat surface  3  (see  FIG. 2   a )). In a first method step a web  5  which projects laterally, in this case perpendicularly, is squeezed out of the flat surface  3  of the elongate sheet metal portion  6 . How that takes place in detail will be described with reference to  FIG. 3   a ). By virtue of the fact that the elongate sheet metal portion  6  is moved relative to the shaping apparatus  10  that web  5  extends in the longitudinal direction  4  of the elongate sheet metal portion  6  (see  FIG. 1 ). 
         [0024]    After the first method step the web  5  is of a given shape which depends on the configuration of the shaping tools used in the first method step. In the illustrated embodiment (see  FIG. 2   c )) the web  5 —considered in cross-section—is of a substantially rectangular shape of a given width  7  and a given height  8 . 
         [0025]    The dimensions of that web  5  can now be modified in further method steps, more specifically by the web  5  being squeezed together, that is to say reduced in its width  7  and increased in its height  8  (see  FIGS. 2   e ),  2   g ),  2   i ) and  2   k )). Depending on the purpose that the web  5  is to achieve it can in principle be of any desired dimensions in dependence on the number of further method steps to be employed. 
         [0026]    Advantageously, during the method steps, a return flow of the sheet metal material into the flat surface  3  of the elongate sheet metal portion  6  is inhibited by delimiting material incisions  9 . 
         [0027]    In general it should also be pointed out that the method is carried out at ambient temperature, that is to say typically at a temperature of between 15° C. and 25° C. It is further preferably provided that the elongate sheet metal portion is advanced by an active drive of the profiling rolls  15 ,  16  and  17 , for example at a speed of between 1 m/min and 300 m/min. In that respect it is possible to conceive of both a continuous mode of operation and also a start-stop mode. 
         [0028]    We now turn to  FIGS. 3   a ) through  3   e ) which show in detail cross-sections along planes II, IV, VI, VIII and X in  FIG. 1 . The basic structure of the shaping apparatuses  10 ,  11 ,  12 ,  13  and  14  used in the five illustrated passes, as already stated, is the same in each case. Each of those shaping apparatuses  10 ,  11 ,  12 ,  13  and  14  includes a profiling roll set with a first profiling roll  15  and two further profiling rolls  16  and  17 , wherein disposed between the first profiling roll  15  and the two further profiling rolls  16  and  17  is a first gap  18  of a gap width substantially corresponding to the material thickness of the elongate sheet metal portion  6 . A second gap  19  is provided between the two further profiling rolls  16  and  17 . 
         [0029]    At its peripheral surface  20  (see  FIG. 1 ) the first profiling roll  15  has an annular bulge  21  of a width  22 . That annular bulge  21  on the first profiling roll  15  and the second gap  19  between the two further profiling rolls  16  and  17  are disposed in mutually opposite relationship. 
         [0030]    In the first four illustrated profiling roll sets  10 ,  11 ,  12  and  13  (see  FIGS. 3   a ) through  3   d )) the axes of rotation  23  and  24  of the two further profiling rolls  16  and  17  are oriented parallel to the axis of rotation  25  of the first profiling roll  15 . Thus the first gap  18  is provided between the peripheral surfaces  26  and  27  of the two further profiling rolls  16  and  17  and the peripheral surface  20  of the first profiling roll  15  and the second gap  19  is between the end faces  28  and  29  of the two further profiling rolls  16  and  17  (see also  FIG. 1 ). 
         [0031]    In the profiling roll set  14  shown in  FIG. 3   e ), in comparison therewith, the axes of rotation  23  and  24  of the two further profiling rolls  16  and  17  are oriented perpendicularly to the axis of rotation  25  of the first profiling roll  15  and at the same time parallel to each other. The first gap  18  is thus between the end faces  28  and  29  of the two further profiling rolls  16  and  17  and the peripheral surface  20  of the first profiling roll  15  (see also  FIG. 1 ). The second gap  19  is between the peripheral surfaces  26  and  27  of the two further profiling rolls  16  and  17 . 
         [0032]    The last-described arrangement of the profiling rolls  15 ,  16  and  17  relative to each other is preferably used at least in the last method step, particularly preferably from the third method step, as that arrangement of the profiling rolls  16  and  17  relative to the flat surface  3  of the elongate sheet metal portion  6  provides that a larger processing surface area is operative. In that way the surfaces of the elongate sheet metal portion  6 , that are adjacent to the squeeze-profiled web  5 , can be smoothed in the concluding method step or steps. 
         [0033]    In a preferred embodiment, instead of the two further profiling rolls  16  and  17 , only one profiling roll  50  is used, having a channel-shaped recess  52  whose width corresponds to the gap width of the second gap  19  between the two further profiling rolls  16  and  17  (see for example  FIG. 3   a )). That situation is shown in  FIGS. 7   a ) and  7   b ),  FIG. 7   a ) showing a cross-sectional view and  FIGS. 7   b ) showing a perspective view. 
         [0034]    How now in detail is the web  5  squeezed out of the elongate sheet metal portion  6  in the course of the first method step? For that purpose the elongate sheet metal portion  6  with the flat surface  3  is passed through the first gap  18  of the first profiling roll set  10  (see  FIG. 3   a )). In that situation a web  5  is squeezed out of the flat surface  3  of the elongate sheet metal portion  6  and squeezed into the second gap  19  arranged between the two further profiling rolls  16  and  17 , by the annular bulge  21  of the first profiling roll  15 , wherein that web  5  substantially corresponds in its dimensions, that is to say in its width  7  and in its height  8 , to the dimensions of the annular bulge  21  of the first profiling roll  15 . 
         [0035]    The action already referred to above of inhibiting the return flow of the sheet metal material into the flat surface  3  of the elongate sheet metal portion  6  is implemented by the annular bulge  21  of the first profiling roll  15  being delimited by projections  30  and  31  which for example can be of a toroidal configuration. Material incisions  9  (see  FIG. 2   c )) are produced by means of those projections  30  and  31 —considered in cross-section—to the right and the left of the squeezed-out web  5 . The fact that the return flow of the sheet metal material during the method steps is inhibited, in the ideal case completely prevented, provides that the material volume of the web  5  remains almost constant. 
         [0036]    To further alter the dimensions  7  and  8  of the web  5  formed in the course of the first method step the elongate sheet metal portion  6 , in further method steps, is passed through further profiling roll sets  11 ,  12 ,  13  and  14 , wherein those profiling roll sets  11 ,  12 ,  13  and  14  each have a width for the second gap  19 , that is reduced stepwise in relation to the preceding profiling roll set  10 ,  11 ,  12  and  13  respectively. In that way the web  5  is positively squeezed together, that is to say the width  7  of the web  5  is reduced and at the same time its height  8  is increased. That can be seen by way of example by means of the succession of steps in  FIGS. 3   a ) through  3   e ). 
         [0037]    As already stated in the introductory part of the description sheet metal profiles comprising for example steel can be produced for drawer extension guides by means of the production method according to the invention. For that purpose, prior to and/or following the squeeze formation of the at least one web  5 , in the course of the first and the at least one further method step, the elongate sheet metal portion is transformed in shape, preferably bent, by means of further profiling rolls. Then in a last method step sheet metal profiles of a predetermined length are severed from a continuous elongate material portion or from an elongate material portion produced in a start-stop mode of operation. 
         [0038]      FIG. 4  shows by way of example in cross-section a possible drawer extension guide  2  which includes two sheet metal profiles  32  and  33  produced by means of an embodiment of the production method according to the invention. Such a drawer extension guide typically has a carcass rail  32  to be fixed to a furniture carcass, a drawer rail  33  to be fixed to the drawer and a central rail  34  mounted moveably between the carcass rail  32  and the drawer rail  33 . Arranged between the rails  32 ,  33  and  34  are typically carriages with load-transmitting rolling bodies  46 ,  47  and  48 ,  49  which permit a relative movement of the rails  32 ,  33  and  34  with respect to each other. 
         [0039]    In the illustrated embodiment both the carcass rail  32  and also the drawer rail  33  include a web  35  and  36  respectively, which webs can be produced by means of the squeeze shaping operation described hereinbefore. In the case of the carcass rail  32  the rolling body  46  arranged between the central rail  34  and the carcass rail  32  runs on the web  35 . In the case of the drawer rail  33  the web  36  serves to space the two rolling bodies  48  and  49  from each other and at the same time to provide a bearing means for the rolling body  48 . 
         [0040]      FIGS. 5   a ) and  5   b ) show a further example of a carcass rail  37 ,  FIG. 5   a ) showing a perspective view and  FIG. 5   b ) showing a cross-sectional view of the carcass rail  37 . Arranged on the flat surface  43  of the carcass rail  37  are two webs  38  and  39  which can be formed by the described squeeze profiling procedure. In this case they represent reinforcing ribs which serve to reinforce the carcass rail  37 . 
         [0041]      FIGS. 6   a ) and  6   b ) show by way of example a central rail  40  of a drawer extension guide,  FIG. 6   a ) showing a perspective overall view and  FIG. 6   b ) showing a portion thereof. Considered in cross-section the illustrated central rail  40  substantially comprises a U-shaped profile, wherein arranged at the two lateral mutually opposite limbs of that U-shaped profile are two squeeze-profiled webs  41  and  42  respectively, which project from the flat surfaces  44  and  45 . The rolling bodies of a carriage (not shown) arranged between the central rail  40  and a drawer rail (also not shown) can run on those webs  41  and  42 , wherein that carriage engages under the webs  41  and  42  in the position of use of the extension guide with the rolling bodies thereof to secure it against being lifted off the central rail  40 . In that way, if the central rail  40  is at the same time also secured to prevent it from lifting off the carcass rail, a tilting play in respect of the drawer, that occurs in particular with a drawer which is completely pulled out, can be prevented. 
         [0042]    Finally it should be noted that the term “rolling body” is to be construed very broadly and can be for example in the form of a roll, a cylindrical roller or a ball. In that case the rolling body can both include a spindle bearing and can also be guided spindle-less for example in a cage.