Abstract:
An outer plate carrier, including a cup-shaped embodied carrier plate ( 110 ) comprising a cylinder-shell shaped cylindrical section ( 130 ) and a circular-disk shaped bottom section ( 120 ). The bottom section ( 120 ) of the carrier plate ( 110 ) carries a cup-shaped hub section ( 140 ), arranged centrally. The cup-shaped hub section includes a cylindrical-shell shaped hub jacket ( 160 ) and a circular-disk shaped hub bottom ( 150 ). The hub bottom ( 150 ) has a smaller diameter than the bottom section ( 120 ) of the carrier plate ( 110 ). The hub bottom ( 150 ) is continuous and embodied in one piece with the carrier plate ( 110 ).

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is filed under 35 U.S.C. §120 and §365(c) as a continuation of International Patent Application No. PCT/DE2010/001383 filed on Nov. 24, 2010, which application claims priority from German Patent Application No. 10 2009 058 622.9 filed Dec. 17, 2009, which applications are incorporated herein by reference in their entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to an outer plate carrier for a clutch, for example, a clutch in a transmission. 
     BACKGROUND OF THE INVENTION 
     Outer plate carriers are essential components of hydraulic clutches and brakes, as for example used in motor vehicles. For example, an outer plate carrier represents a clutch inlet, transmitting a torque from an internal combustion engine to the plates of the outer plate carrier. Appropriate multi-disk clutches are known for example from DE 103 09 566 A1. 
     Outer plate carriers of the prior art comprise a clutch basket and a connection part, with an inlet gearing being embodied on a hub area. The basket and the connection part are connected to each other via engaging gears and a circlip. The hub comprises a forging blank processed in a cutting fashion, which is welded to a connection part formed from sheet metal. This embodiment is disadvantageous by its high production costs. Particularly the production of the forging blank is expensive. 
     BRIEF SUMMARY OF THE INVENTION 
     The objective of the present invention therefore comprises to provide an improved outer plate carrier. 
     The outer plate carrier according to the invention comprises a cup-shaped carrier plate with a cylindrical-shell shaped cylinder section and a circular-disk shaped bottom section. The bottom section of the carrier plate comprises a cup-shaped hub section, arranged centrally, with a cylinder-shell shaped hub jacket and a circular-disk shaped hub bottom. The hub bottom has a smaller diameter than the bottom section of the carrier plate. The hub bottom is continuous. Additionally the support plate is embodied in one piece. Advantageously this outer plate carrier can be produced very easily and cost-effectively. 
     In one embodiment, a cylinder-shell shaped geared sleeve, provided radially outwardly with an outer gearing, is arranged radially outwardly on the hub material. Advantageously the geared sheath may show a different hardness than the carrier plate of the outer plate carrier. 
     In a first embodiment of the outer plate carrier, the geared sheath is welded to the hub shell and/or an axial stop of the bottom section of the carrier plate. Advantageously here a connection can be established in a simple and cost-effective manner between the geared sheath and the hub shell. 
     In an alternative embodiment of the outer plate carrier, the geared sheath comprises radially inwardly an inner gearing and is connected by way of caulking to the hub shell. Advantageously by this connection technology any change of the gearing of the geared sleeve can be avoided, caused by excessive introduction of heat. In one embodiment, the geared sheath comprises at its end facing the bottom section a chip chamber embodied as a circumferential recess. Advantageously, this chip chamber then can accept chips of the geared sheath developing during the caulking process. 
     In one embodiment of the outer plate carrier, the outer gears of the geared sheath are rolled. Here the cold hardening of the material of the geared sheath can be used, advantageous in reference to cutting production processes. 
     In an alternative embodiment of the outer plate carrier, the outer gears of the geared sleeve are axially extruded. Advantageously here the cold hardening of the material of the geared sleeve can be used. 
     In one embodiment, the geared sheath shows a greater hardness than the carrier plate. Advantageously, this greater hardness minimizes the wear and tear of the geared sheath. 
     In one embodiment, the carrier plate comprises a cylinder-shell shaped sealing area in a transition area between the bottom section and the hub section. A cylinder-shell shaped sealing sheath is pressed radially outwardly onto the sealing area. Advantageously it is more cost-effective to use such a sealing sleeve than to cure the hub area of the carrier plate. Additionally, when a sealing sheath is used any potentially harmful accumulation of carbon in the welding zones of the hub area of the support plate can be ignored. 
     In one embodiment, the outer plate carrier is embodied for the use in hydraulic clutches of a transmission of a motor vehicle. 
     In one embodiment, the sealing sheath is extruded in a non-cutting fashion and carbonized. The carrier plate is, for example, deep-drawn and may be made from steel of the quality DD12, for example. The carrier plate may be coated, such as nitro-carbureted, after the necessary welding processes. When the geared sheath is welded to the hub shell and/or an axial stop of the bottom section of the carrier plate preferably laser-welding is used. Even in case the geared shell is connected to the hub material by way of caulking one or more welding points might be provided between the geared shell and the hub shell for an axial securing of the geared sheath. The geared sheath is preferably made from steel of the quality 16MnCr5 and is hardened to the tensile strength of 650 to 750 N/mm 2 . The described plate carrier may also be used in a hydraulic brake. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       In the following, the invention is explained based on the figures: 
         FIG. 1  is a schematic and partially opened, perspective illustration of an outer plate carrier; 
         FIG. 2  is a detail of the outer plate carrier of  FIG. 1 ; 
         FIG. 3  is a schematic and partially opened, perspective illustration of an outer plate carrier; and 
         FIG. 4  is another view of the outer plate carrier of  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The outer plate carrier  100  may for example be used in a hydraulic clutch of a transmission of a motor vehicle embodied as a multi-disk clutch. The use of the outer plate carrier  100  in a hydraulic brake of a motor vehicle is also possible. 
       FIG. 1  is a schematic and partially opened, perspective illustration of outer plate carrier  100 . The outer plate carrier  100  comprises a cup-shaped embodied carrier plate  110  with a circular-disk shaped bottom section  120  and a cylindrical-shell shaped cylinder section  130 . The carrier plate  110  may be made from a material with low stability, for example steel of the quality DD12. The carrier plate  110  may be produced by way of deep-drawing, for example. 
     The cylinder section  130  of the carrier plate  110  comprises at its radially outer surface a plurality of inner suspended plates, which are embodied according to prior art and thus require no further explanation. The cylinder section  130  of the carrier plate  110  comprises a circumferential plate gearing  400  according to prior art. 
     The carrier plate  110  further comprises a cup-shaped embodied hub section  140  with a circular-disk shaped hub bottom  150  and a cylindrical-shell shaped hub jacket  160 . The cup-shaped hub section  140  is arranged in the center of the circular-disk shaped bottom section  120  of the carrier plate  110  and points in the direction opposite the cylinder section  130  of the carrier plate  110 . In the transition area between the hub jacket  160  of the hub area  140  and the bottom section  120  of the carrier plate  110  a circular-disk shaped axial stop  170  and a cylindrical-shell shaped sealing area  180  are embodied. The axial stop  170  is here approximately parallel in reference to the bottom section  120  of the carrier plate  110  and oriented towards the hub bottom  150  of the hub area  140 . According to the present exemplary embodiment, the sealing area  180  is oriented concentrically in reference to the cylinder section  130  of the carrier plate  110  and the hub jacket  160  of the hub area  140 . The sealing area  180  shows a greater diameter than the hub jacket  160  and a smaller diameter than the cylinder section  130 . The other areas of the bottom sections  120  do not necessarily need to be embodied completely planar. The hub area  140  is continuous in the area of the hub bottom  150  and the hub jacket  160 . 
     A cylindrical-shell shaped gearing sheath  200  is arranged radially outwardly on the hub jacket  160 . The geared sheath  200  comprises radially outwardly an outer gearing  210 . The outer gearing  210  may for example comply with the standard DIN 5480-W50×1×30×48 8f. The outer gearing  210  may be rolled or axially extruded. For the production of the outer gearing  210  of the geared sheath  200  the ability for cold forming the material of the geared sheath  200  is utilized. The increased stability by the cold formation may here amount from 10% to 30%. The axial length of the geared sheath  200  is approximately equivalent to the axial length of the hub jacket  160 . 
       FIG. 2  is a detail of the outer plate carrier of  FIG. 1 . It is discernible in  FIG. 2  that the radially inner surface of the geared sheath  200  is essentially embodied smoothly and contacts the surface of the hub jacket  160 . The geared sheath  200  is connected to the carrier sheath  110  by way of welding. At the axial end of the geared sheath  200 , facing away from the axial stop  170 , a hub bottom  150  provides via a circumferential perimeter welding  220  a connection between the geared sheath  200  and the hub jacket  160  of the hub area  140 . At the end of the geared sheath  200 , facing the axial stop  170 , a circumferential facial welding  230  provides a connection between the geared sheath  200  and the axial stop  170  of the carrier plate  110 . The circumferential welding  220  or the facial welding  230  may optionally be omitted, though. The circumferential welding  220  and the facial welding  230  are preferably produced by laser welding. 
       FIG. 2  additionally shows that an annular sealing sheath  300  is arranged about the cylindrical-shell shaped sealing area  180  of the carrier plate  110 . The sealing sheath  300  is embodied as a thin metal band, with its axial length being approximately equivalent to the length of the sealing area  180 . The radially outward surface of the sealing sheath  300  forms a sealing surface  310 . The sealing surface  310  preferably comprises a strong hardness and little roughness. The sealing sheath  300  is pressed upon the sealing area  180  of the carrier plate  110 . The sealing sheath  300  is preferably extruded in a non-cutting fashion and has been carbonized. Advantageously, by the use of the sealing sheath  300  any carbonizing of the sealing area  180  of the carrier plate  110  can be waived. Additionally, a harmful accumulation of carbon that may develop in the area of the welding zones during the implementation of the circumferential welding  220  and the facial welding  230  can be ignored. 
       FIG. 3  shows a perspective cross-section of an outer plate carrier  1100 . Here, elements equivalent to the first embodiment of  FIGS. 1 and 2  were marked with the reference characters already introduced, and are not described anew in the following. In the outer plate carrier  1100  of  FIG. 3 , instead of the geared sheath  200 , a differently embodied geared sheath  1200  is provided at the hub jacket  160  of the hub area  140  of the carrier plate  110 , which however in the illustration of  FIG. 3  has not yet been fastened to the hub area  140 . The geared sheath  1200  is once more embodied in a cylindrical-shell shaped fashion and comprises an axial length approximately equivalent to the length of the hub jacket  160 . The radially outward jacket surface of the geared sheath  1200  comprises an exterior gearing  1210 , which may be embodied like the exterior gearing  210  of the geared sheath  200 . Additionally, the radially inner jacket surface of the geared sheath  1200  may show an inner gearing  1220 . The teeth of the inner gearing  1220  are oriented parallel in reference to the axial direction of extension of the geared sheath  1200 . Additionally, the geared sheath  1200  is provided at its end facing the bottom section  120  of the carrier plate  110  as a chip chamber  1230  embodied as a circumferential recess. The chip chamber  1230  may also be omitted in a simplified embodiment. 
       FIG. 4  shows another illustration of the outer plate carrier  1100  of  FIG. 3 . In  FIG. 4  the geared sheath  1200  was connected to the hub jacket  160  of the hub area  140  of the carrier plate  110  by way of caulking. The inner diameter of the cylindrical-shell shaped geared sheath  1200  is approximately equivalent to the radial diameter of the hub area  140 . When the geared sheath  1200  is pressured in the axial direction upon the hub area  140  of the carrier plate  110  the inner gearing  1220  of the geared sheath  1200  cuts a counter gearing into the hub jacket  160  of the hub area  140  matching the inner gearing  1220 . Here, chips developing from the material of the hub jacket  160  are accepted in the chip chamber  1230 . The inner gearing  1220  and the counter gearing formed in the hub jacket  160  by the inner gearing lead to a tight fit of the geared sheath  1200  on the hub jacket  160 . In particular, the gearing generates a protection of the geared sheath  1200  from any distortion in the circumferential direction of the hub jacket  160 . In the axial direction the geared sheath  1200  can be secured by one or more additional welding points between the geared sheath  1200  and the carrier plate  110 . The fastening of the geared sheath  1200  described in  FIGS. 3 and 4  on the carrier plate  110  by way of caulking shows the advantage in reference to the fastening described in  FIGS. 1 and 2  of the geared sheath  200  at the carrier plate  110  by welding connections  220 ,  230  that due to the lesser introduction of heat any considerable change of the outer gearing  1210  is minimized. 
     The geared sheath  200 ,  1200  preferably shows a greater hardness than the carrier plate  110 . The geared sheath  200 ,  1200  may for example be made from steel of the quality 16MnCr5 and cured for the required hardness level. 
     The carrier plate  110  may be coated to avoid wear and tear at the plate gearing  400 , for example by way of nitro-carburetion. Preferably the coating occurs after the welding connections  220 ,  230  and/or the point-welding connection have been implemented to fasten the geared sheath  1200 , however prior to the sealing sheath  300  being pressed thereon. This way any covering of the welding zones is not necessary. 
     LIST OF REFERENCE CHARACTER 
     
         
           100  outer plate carrier 
           110  carrier plate 
           120  bottom section 
           130  cylinder section 
           140  hub section 
           150  hub bottom 
           160  hub jacket 
           170  axial stop 
           180  sealing area 
           200  geared sheath 
           210  outer gearing 
           220  circumferential welding 
           230  facial welding 
           300  sealing sheath 
           310  sealing area 
           400  plate gearing 
           1100  outer plate carrier 
           1200  geared sheath 
           1210  outer gearing 
           1220  inner gearing 
           1230  chip chamber