Abstract:
A cage section ( 36 ), particularly for a meander-shaped cage ( 12 ) of a rolling contact bearing ( 14, 15 ), including at least one cage part ( 10, 11, 11 ′) made of a Z-shaped bent sheet-metal strip ( 16, 17 ) with a first arm ( 20 ), a connecting part ( 18 ) and a second arm ( 22 ), wherein the first arm ( 20 ) and the second arm ( 22 ) are bent substantially perpendicularly to the sheet metal plane ( 23 ). The invention further relates to a method for producing a cage portion ( 36 ), particularly for a meander-shaped cage ( 12 ) of a rolling contact bearing ( 14, 15 ).

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates to a cage section for, in particular, a meander-shaped cage of a rolling contact bearing, as well as a method for the production of such a cage section. In particular, the cage section is suitable for the construction of a segmented cage of a roller bearing. 
       BACKGROUND 
       [0002]    Typically, rolling bodies of a large rolling contact bearing are held and guided in a cage, in order to prevent, for example, clamping of the rolling bodies due to mutual support. Typically, e.g., the rollers of a large roller bearing with cylindrical bearing roller or tapered bearing roller construction have a cage-guided construction. 
         [0003]    From DE 424 712 A, a cage for a rolling contact bearing is known that encloses and individually guides the rollers of the rolling contact bearing. The cage is made from solid material through material-cutting processes, wherein the production of the cage is complicated and the material expense is high. A disadvantageous result is high production costs. 
         [0004]    An integral cage consisting of two completely identical halves that are welded together for a roller bearing is known from DE 433 223 A. The halves are produced from a sheet-metal part through shaping. A disadvantage in this type of production is that, with increasing size of the cage, the integral sheet-metal shaping becomes more and more expensive. The costs for the required tools increase, wherein simultaneously the production batch sizes decrease. In addition, there are many sheet metal cutting processes. Because two cage connecting parts lie between two adjacent rollers, the number of rollers that can be used is limited, which limits the load rating of the roller bearing. 
         [0005]    In addition, from DE 585 099 A, a segmented cage for a roller bearing is known. The cage is assembled from several cage segments that are produced from a metal sheet and are held together with additional covers. For connecting the cage segments, complicated edge projections or tabs are required. In addition, two edge plates are required. The production costs of such a cage are high. 
     
    
     SUMMARY 
       [0006]    In recognition of these conditions, the invention is based on the objective of providing a cage section for, in particular, a meander-shaped cage of a rolling contact bearing and a method for its production. Here, the starting material should be used as optimally as possible and should make possible a simple, economical production. 
         [0007]    The objective mentioned first with regard to a cage section is achieved according to the invention by a cage section for, in particular, a meander-shaped cage of a rolling contact bearing, comprising at least one cage part made from a Z-shaped, bent sheet-metal strip with a first arm, a connecting part, and a second arm, wherein the first arm and the second arm are bent essentially at a right angle to the plane of the sheet metal. 
         [0008]    The cage section comprises at least one Z-shaped, bent cage part that is made from a flat metal sheet in a simple way. The cage part has, on one connecting part, a first arm that is angled essentially at a right angle to the sheet metal plane. On the connecting part there is a second arm oriented essentially perpendicular to the sheet metal plane. Cage sections or complete, in particular, meander-shaped cages can be produced from a plurality of such cage parts in a Z-shape through the series arrangement of the arms in a simple way. Through two at least partially overlapping arms and two connecting parts of adjacent cage parts, a cage pocket for a corresponding rolling body is formed. The cage parts do not have to have identical constructions. In particular, through two cage parts that are different from each other, e.g., with differently shaped arms, a meander-shaped cage could be provided. The arms of a cage part could also differ from each other, e.g., in width or length. 
         [0009]    The objective mentioned second with regard to a method is achieved according to the invention by a method for the production of a cage section for, in particular, a meander-shaped cage of a rolling contact bearing, wherein a sheet-metal strip is cut from a metal sheet and wherein the sheet-metal strip is shaped into a Z-shape with a first arm, a connecting part, and a second arm, so that the first arm and the second arm are angled essentially at a right angle to the sheet metal plane. 
         [0010]    Accordingly, at first a flat strip is cut out from a metal sheet. The cut-out strip is shaped into a Z-shaped cage part with a first arm, a connecting part, and a second arm, and the two arms are bent away from the connecting part essentially perpendicular to the sheet metal plane. A cage section comprises at least one Z-shaped cage part. A cage section, however, can also comprise several of the cage parts. Adjacent cage parts are placed one above the other with their arms. Several cage parts can be assembled to form a complete, in particular, meander-shaped cage. 
         [0011]    The specified cage section or the specified cage part can be produced from a metal sheet with the help of simple tools and with minimal cutting. The sheet metal strip is, in particular, punched out and bent into a Z-shaped cage part. From the cage parts or from the cage sections comprising a number of such cage parts, a cage for large roller bearings can be easily assembled. For this purpose, two Z-shaped cage parts are placed one above the other with their arms and, in particular, connected rigidly to each other. For example, the arms of adjacent cage parts can be connected to each other by welding, soldering, swaging, beading, bonding, and/or clinching. 
         [0012]    Preferably, a cage section comprises at least two of the previously described cage parts that are assembled into a U-shaped overlapping at their arms. Such a cage section forms, to some extent, a cage pocket in which a rolling body is held and guided. The two cage parts are advantageously connected to each other in an angled arrangement at the overlapping arms. In particular, the previously mentioned joining methods are suitable for connecting the arms. The curvature and thus the size of the complete, ring-shaped cage are defined by the angle between the overlapping arms of the two cage parts of a U-shaped cage section. The angle is greater than 90° and less than 180°. 
         [0013]    Advantageously, a plurality of U-shaped assembled from two cage parts is set one on the other with the same orientation to form a larger cage section or a complete cage, wherein the free arms of each U-shape are alternately arranged on and under a free arm of the adjacent U-shapes. Accordingly, the individual U-shaped cage sections are arranged in a fixed pattern relative to each other. In a series arrangement of the U-shaped cage sections, the two free arms are alternately placed on and under the adjacent arm of the surrounding U-shaped cage sections. This produces overall a mechanically very stable joint. The individual U-shaped cage sections are prevented from falling out by the alternating support of the arms. In particular, tilting of the U-shapes or the individual cage parts is prevented when the rolling bodies are held in the cage. 
         [0014]    In one preferred construction, at least one arm of the Z-shaped cage part is expanded with a rounded section. Such a rounded section expanding the arm in its width is used for optimizing the guiding of the cage in the rolling contact bearing, in particular, for a rim or raceway guidance on an inner ring and/or on an outer ring of the rolling contact bearing. The axial position of the cage part or the cage in the rolling contact bearing is defined by the radius of the rounded section. In particular, both arms of a cage part can be expanded with different size rounded sections. One arm is here guided, for example, on an inner ring and one arm on the outer ring of the rolling contact bearing. The guidance of the cage by means of the arms of the cage parts can be performed, in particular, outside of the raceway of the rolling bodies, which reduces the wear on the raceway. 
         [0015]    In one advantageous refinement, a number of raised contours are formed at least in one of the arms of the cage part or each cage part. The raised contours can be point-shaped, round, or angular and can be formed, for example, by embossing or swaging. Through the raised contours, for the guidance of the rolling bodies, the friction is reduced, because the rolling body contacts the cage or the cage part only on these contours. The contact surface of a rolling body produced by the raised contours with the cage part is smaller by a multiple than a contact surface with direct contact on the arm of the cage part. In the present case, a roller-shaped or barrel-shaped rolling body is guided in the cage formed from the cage parts by means of its end face on an arm of the cage part. 
         [0016]    In a further preferred way, a number of raised, in particular, alternating contours is formed in the connecting part of the cage part or each cage part. In the finished cage, a roller-shaped or barrel-shaped rolling body is supported on these contours with its lateral surface. Through alternating contours, two successive rolling bodies are guided on one connecting part. Two rolling bodies are spaced apart from each other and guided by the connecting part of a cage part. 
         [0017]    In one preferred alternative, a tab is formed on at least one of the arms of the cage part or each cage part at the end, which encloses an acute angle with its longitudinal axis with respect to the unshaped flat sheet metal strip. For the assembly of two adjacent cage parts, the angle of the overlapping arms is set relative each other by means of the angle of the tab to the longitudinal axis. Here, the tab of an arm of the cage part is supported on the connecting part of the other cage part. A complicated tool is not required to maintain the angle specified for forming the ring-shaped cage during the assembly of the individual cage parts. The length of the tab defines the distance of the Z-shaped cage parts to be connected to each other. In other words, the tab represents an assembly aid for orienting two adjacent cage parts. In addition, the tab stabilizes a joint built from a plurality of cage parts. Through the stop of the tab on the connecting part of the adjacent cage part, in the finished cage, operating play is generated for the rolling bodies in the circumferential direction, so that jamming of rolling bodies supported one on the other is reliably prevented. 
         [0018]    Advantageously, a recess is formed in the transition between an arm and the connecting part of a cage part or each cage part. The previously mentioned tab engages in such a recess for the assembly of the cage, which further mechanically stabilizes the shown joint made from cage parts. 
         [0019]    In one advantageous refinement, several of the previously described U-shaped cage sections are assembled into a cage or connected rigidly to each other to form an integral cage. In particular, two different cage parts are connected to each other. The U-shaped cage sections are here arranged in a fixed pattern relative to each other. In particular, for the series arrangement of the U-shaped cage sections, the two free arms are alternatively placed on and under the adjacent arm of the surrounding U-shaped cage sections. This produces overall a mechanically very stable joint. The individual U-shaped cage sections are prevented from falling out in the axial direction by the alternating support of the arms. 
         [0020]    Another aspect of the invention is, in particular, a meander-shaped rolling contact bearing, in particular, a roller bearing, with an outer ring, an inner ring, and several rolling bodies guided in a cage, wherein the cage is assembled from several of the previously mentioned cage sections. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    Embodiments of the invention will be explained in more detail with reference to a drawing and with reference to the following description. Shown in schematic representation are: 
           [0022]      FIG. 1  a flat sheet-metal strip for a Z-shaped, bent cage part in a first embodiment, 
           [0023]      FIG. 2  the Z-shaped, bent cage part according to the first embodiment, 
           [0024]      FIG. 3  a flat sheet-metal strip for a Z-shaped, bent cage part in a second embodiment, 
           [0025]      FIG. 4  the Z-shaped, bent cage part according to the second embodiment, 
           [0026]      FIG. 5  a U-shaped cage section assembled from two Z-shaped, bent cage parts, 
           [0027]      FIG. 6  a plurality of assembled U-shaped cage sections, 
           [0028]      FIG. 7  a cage assembled from a plurality of U-shaped cage sections, 
           [0029]      FIG. 8  a roller bearing in two cross-sectional views, and 
           [0030]      FIG. 9  a part of a roller bearing in a side view. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0031]      FIG. 1  shows a cutout flat sheet metal strip  16  for the production of a cage part  10  (see  FIG. 2 ) according to a first embodiment. The flat sheet metal strip  16  comprises a first arm  20 , a connecting part  18 , and a second arm  22 . On both sides of the connecting part  18  there is a transition area  32  to the two arms  20 ,  22 . The longitudinal axis  30  of the flat sheet metal strip  16  is indicated with a dashed line. For the sheet metal plane  23 , the surface normals are shown. The second arm  22  ends in a rounded section  26  that projects over the connecting part  18  or the arm  22  in the respective width. The connecting part  18  further has a number of stamped, raised contours  24  with an approximately angular cross-sectional surface. The contours  24  are formed alternating. Along the longitudinal axis  30  of the connecting part  18 , they extend alternately out of the plane of the drawing toward the viewer and into the plane of the drawing away from the viewer. The first arm  20  has the width of the connecting part  18 . Raised contours  24  with an approximately circular cross section are formed in the first arm  20 . The round and angular raised contours  24  form, in the finished cage part  10 , the respective contact surfaces for a rolling body  42 . 
         [0032]    In  FIG. 2 , the cage part  10  shaped from the sheet metal strip  16  of  FIG. 1  into a Z-like shape can be seen. The two arms  20 ,  22  are lifted from the connecting part  18  in opposite directions essentially perpendicular to the sheet metal plane  23 . The rounded section  26  of the second arm  22  represents, in a cage assembled from the cage parts  10  (see, e.g.,  FIGS. 6 ,  8 ), in particular, a guide on a rim of an inner ring or outer ring of a rolling contact bearing. A roller in the cage as a rolling body is supported with its lateral surface on the connecting part  18  and with its end face on the first arm  20  or on the contours  24 . The second arm  22  is formed for fastening onto an overlapping first arm  20  of an adjacent cage part  10 . The operating play can be specified in the circumferential direction for a rolling body by means of the length of the first arm  20 . In the finished cage, for example, the first arm  20  is supported on the connecting part  18  of the adjacent cage part  10 . Therefore, in particular, eliminated from the shown embodiments, the length of the first arm  20  is greater than the diameter of the rolling body. 
         [0033]    In  FIG. 3 , a cutout flat sheet metal strip  17  is shown for a cage part  11  according to a second embodiment (see  FIG. 4 ). The flat sheet metal strip  17  comprises, in turn, a first arm  20 , a connecting part  18 , and a second arm  22 . In the present case, both arms  20 ,  22  end in rounded sections  26  that differ in their size. A tab  28  is formed on the first arm  20 , wherein this arm is at an acute angle  44  relative to the longitudinal axis  30  of the sheet metal strip  17 . In the transition area  32  between the second arm  22  and the connecting part  18  there is also a recess  34 . The connecting part  18  and the first arm  20  have, in turn, a number of raised contours  24  for guiding a rolling body. 
         [0034]      FIG. 4  shows the Z-shaped cage part  10  produced by shaping the sheet metal strip  17  according to  FIG. 3  according to the second embodiment with arms  20 ,  22  bent essentially perpendicular to the sheet metal plane  23 . The connecting part  18  has raised contours  24  alternately on both sides with an essentially angular basic shape, with these contours being formed by pressing. Also on the first arm  20 , raised contours  24  for guiding a rolling body are visible. The contours  24  of the first arm  20  extend downward in the drawing. Both arms  20 ,  22  are used for guiding the corresponding end sides of rollers that are used as rolling bodies and are spaced apart from each other by the connecting part  18  of the cage part  11 . On the first arm  20 , the rolling body is guided directly by means of the raised contours  24 . A corresponding second arm  22  of an adjacent cage part with contours  24  is placed on the second arm  22 , on which then, in turn, the corresponding rolling body is supported directly. The recess  34  is visible on the transition area  32  between the second arm  22  and the connecting part  18 . 
         [0035]    In  FIG. 5 , a U-shaped cage section  36  assembled from two Z-shaped, bent cage parts  11 ,  11 ′ is shown. The cage part  11  shown on the left in  FIG. 5  corresponds to the cage part  11  according to  FIG. 4 . The cage part  11 ′ shown on the right in the drawing is modified compared with the construction of the arms  20 ,  22 . For example, the first arm  20  of the right cage part  11 ′ has no raised contours  24  for guiding a rolling body. Also, on the first arm  20  of the second cage part  11 ′, a corresponding tab  28  is missing. However, a tab  28  that is not visible in  FIG. 5  is formed, instead, on the second arm  22  of the right cage part  11 ′. 
         [0036]    Between the cage parts  11 ,  11 ′, a produced cage pocket  37  for holding a roller or cylindrical rolling body can be seen. The rolling body located therein is guided with its lateral surface on the contours  24  of the connecting parts  18  projecting into the cage pocket  37  and with its lower end face on the contours  24  of the second arm  22  of the right cage part  11 ′. 
         [0037]    The second or right cage part  11 ′ is placed in an angled arrangement with its modified second arm  22  on the second arm  22  of the first or left cage part  11 . The cage parts  11 ,  11 ′ are connected rigidly to each other at the arms  20 ,  22 . The connection can be realized, for example, through welding, soldering, swaging, beading, bonding, or clinching. Here, each rounded section  26  of the second arms  22  of the left cage part  11  and the right cage part  11 ′ overlap each other. The tab  28  set on the rounded section  26  of the second arm  22  of the right cage part  11 ′ is supported in the recess  34  formed at the transition  32  between the second arm  22  and the connecting part  18  of the left cage part  11 . Through the engagement of the tab  28  in the recess  34 , on one hand the assembly of the two cage parts  11 ,  11 ′ is simplified and on the other hand a higher stability of the U-shaped cage section  36  is achieved. In addition, operating play is set in this way for the rolling bodies in the circumferential direction, so that jamming of adjacent rolling bodies is prevented. 
         [0038]    The two arms  20 ,  22  of successive cage parts  11 ,  11 ′ are connected to each other so that they enclose an obtuse angle relative to each other. The angle is produced during assembly by the interaction of the tabs  28  and recesses  34 . The size of the complete rolling contact bearing is given by the size of the angle at which the U-shaped cage sections  36  are joined to each other. 
         [0039]    The U-shaped cage section  36  shown in  FIG. 5  and assembled from cage parts  11 ,  11 ′ could also be formed from cage parts  10 , as shown in  FIGS. 1 and 2 . 
         [0040]    In  FIG. 6 , a larger cage section  36  formed from a plurality of cage parts  10  corresponding to  FIG. 2  is shown with roller-shaped rolling bodies  42 . Every two cage parts  10  are joined to each other with alternating orientation. The U-shaped cage section produced from every two adjacent cage parts  10  are joined together in the same orientation. The first arm  20  of a cage part  10  is always oriented with its contours  24  inward relative to the end side of each rolling body  42 . A second arm  22  contacts a first arm  20  on the outside. With this joining pattern, a complete, meander-shaped cage is produced overall. After setting the rolling bodies  42  in the cage  12 , the U-shaped cage sections are self-supporting. 
         [0041]    In  FIG. 7 , a complete, meander-shaped cage  12  is shown, like that produced by an identically oriented, series arrangement of U-shaped cage sections  36  from  FIG. 5 . 
         [0042]    In  FIG. 8 , in two cross sections a) and b), a rolling contact bearing  14  formed as a roller bearing is shown with a cage made from two different, alternating cage parts  10  according to  FIG. 2  set one on the other. Adjacent cage parts  10  differ here in the size of each rounded section  26  formed on the second arm  22 . Cross section a) and cross section b) run in the rolling contact bearing  12  through successive, adjacent rolling bodies  42 .  FIG. 8  shows, between an outer ring  38  and an inner ring  40 , a rolling body  42 . This rolls with its lateral surface  48  on a raceway of an outer ring  38  and an inner ring  40 . For guiding the rolling bodies  42 , both the inner ring  40  and also the outer ring  38  each have at least one rim  50 . 
         [0043]    In the shown cross section a), the rolling body  42  on the left is guided on the first arm  20  of a cage part. A second arm  22  of an adjacent cage part contacts the first arm  20 . By means of the rounded section  26  of the second arm, every second cage part on the left of the rolling body  42  is guided with little play between the outer ring  38  and the inner ring  40  of the rolling contact bearing  14  outside of the raceway. On the right side of the rolling body  42  there is a view of the transition area  32  of the next cage part. 
         [0044]    In the shown cross section b), the rolling body  42  on the right is guided on the first arm  20  of a cage part. A second arm  22  of an adjacent cage part contacts the first arm  20 . The rounded section  26  visible in cross section b) belongs to another cage part than the rounded section  26  in cross section a). The rounded sections  26  differ in size. By means of the rounded section  26  of the second arm, every second cage part on the right of the rolling body  42  is guided with little play between the outer ring  38  and the inner ring  40  of the rolling contact bearing outside of the raceway. On the left side of the rolling body  42  there is a view of the transition area  32  of the next cage part. 
         [0045]    A sealing ring  52  is also inserted in the drawing on the left between the outer ring  38  and the inner ring  40  of the shown rolling contact bearing  12 . 
         [0046]      FIG. 9  shows a lateral view of a part of another rolling contact bearing  15  formed as a roller bearing. The rolling contact bearing  15  has an outer ring  38  and an inner ring  40  each with a rim  50 . For guiding the rolling body  42 , a cage  12  according to  FIG. 7  is used. Visible are the overlapping first arms  20  of the corresponding cage parts  11 ,  11 ′ joined to each other at an angle. Through the width of the rounded sections  26  of each first arm  20 , the distance of the respective cage part  11  to the outer ring  38  and inner ring  40  is set. The cage  12  is guided by the rims in the rolling contact bearing  14 . On the first arm  20  of a cage part  11 , the recess  34  is also visible in which the tab  28  of a second cage part  11 ′ engages. The rolling bodies  42  are each guided between two raised contours  24  of two connecting parts  18  of adjacent cage parts  11 ,  11 ′. 
       LIST OF REFERENCE NUMBERS 
       [0000]    
       
           10  Cage part 
           11 Cage part 
           11 ′ Cage part 
           12  Cage 
           14  Rolling contact bearing 
           15  Rolling contact bearing 
           16  Sheet-metal strip 
           17  Sheet-metal strip 
           18  Connecting part 
           20  First arm 
           22  Second arm 
           23  Sheet-metal plane 
           24  Raised contour 
           26  Rounded section 
           28  Tab 
           30  Longitudinal axis of the sheet-metal strip 
           32  Transition area 
           34  Recess 
           36  Cage section 
           37  Cage pocket 
           38  Outer ring 
           40  Inner ring 
           42  Rolling body 
           44  Acute angle 
           48  Lateral surface 
           50  Rim 
           52  Sealing ring