Abstract:
An automotive clutch housing and a method of manufacture thereof is provided. The clutch housing has a cylindrical body that is formed from a form folded strip metal sheet that is later formed into a cylindrical body. The cylindrical body is then joined to a hub to form a clutch housing.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. patent application Ser. No. 13/030,257, filed Feb. 18, 2011, which claims the benefit of U.S. Provisional Application No. 61/338,897 filed Feb. 25, 2010. 
         [0002]    This application also claims priority to German Patent Application No. 10 2011 003 824.8, filed Feb. 9, 2011, said priority claim being limited to additional disclosure not set forth in U.S. patent application Ser. No. 13/030,257. 
     
    
     FIELD OF THE INVENTION 
       [0003]    The present invention relates to clutch housings for automotive transmissions in automotive vehicles such as, but not limited to, passenger vehicles, motor cycles, rough-terrain vehicles and trucks. 
       BACKGROUND OF THE INVENTION 
       [0004]    Many, if not most, automotive clutch housings are fabricated from a cylindrical work piece. Spline teeth are then formed or cut into the cylindrical work piece. It is desirable to provide a clutch housing where the spline teeth of the clutch housing can be formed on a generally flat work piece that is later formed into a cylinder. 
       SUMMARY OF THE INVENTION 
       [0005]    In a preferred embodiment, the present invention provides a clutch housing that is formed from a work piece of sheet strip material. The work piece has spline teeth form folded thereon. The form folded work piece is then formed into a cylinder body and is connected with a hub portion of the clutch housing. 
         [0006]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
           [0008]      FIG. 1  is a perspective view of a cylindrical body of A clutch housing according to the present invention; 
           [0009]      FIG. 2  is a schematic view of a generally flat metallic sheet metal work piece utilized to form THE cylindrical body of the clutch housing of the present invention; 
           [0010]      FIG. 3  is a schematic view of a work piece shown in  FIG. 2  being form folded by press brake tooling into a cylindrical BODY for the clutch housing of the present invention; 
           [0011]      FIG. 4  is a schematic view of an alternative fold forming operation wherein splined teeth of the cylindrical body are formed by a rolling operation; 
           [0012]      FIG. 5  is a top view of a clutch housing of the present invention; 
           [0013]      FIG. 6  is a sectional view taken along lines  6 - 6  of  FIG. 5 ; 
           [0014]      FIG. 7  is a perspective view of the clutch housing shown in  FIG. 5 ; 
           [0015]      FIG. 8  is a front perspective view of a hub utilized in the clutch housing shown in  FIG. 5 ; 
           [0016]      FIG. 9  is a rear perspective view of the hub shown in  FIG. 8 ; 
           [0017]      FIG. 10  is a front view of the hub shown in  FIG. 8 ; 
           [0018]      FIG. 11  is a sectional view of the hub shown in  FIG. 8  taken along lines  11 - 11  of  FIG. 10 ; 
           [0019]      FIG. 12  is an enlargement of a portion that is circled in  FIG. 10 ; 
           [0020]      FIG. 13  is a side perspective view of the hub shown in  FIG. 8 ; and 
           [0021]      FIG. 14  is an enlargement of a portion  14  encircled in  FIG. 13 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0022]    The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
         [0023]    Referring to  FIG. 1 , cylindrical body  410  for the clutch housing  407  ( FIG. 7 ) according to the present invention is shown. The cylindrical body  410  is fabricated from a fold formed strip sheet metal work piece  16  ( FIG. 2 ). Typically, steel is the material of choice. Typical cylindrical body  410  thicknesses can be approximately 1.5 mm. The cylindrical body  410  has a series of spline teeth  414 . The spline teeth  414  of the cylindrical body has an inner flat  413  and an outer flat  417  that are joined by slope portions  419 . 
         [0024]    To fabricate the cylindrical body from the press brake tooling  41  is utilized having a re-hit portion  43 . The press brake tooling  41  and  43  stamp the spline teeth  414  into the shape of the cylindrical body. The spline teeth  414 , as schematically shown in  FIG. 4 , can also be roll formed from a continuous flat strip work piece  16 . In a subsequent operation (not shown), an individual cylindrical body  410  is cut off. 
         [0025]    The cylindrical body  410  has along its opposite ends, a dove tail interlock joint comprising a male tab  24  ( FIG. 2 ) and a corresponding female cut out  26 . The ends of the cylindrical body  435  and  437  are brought together to form the cylindrical shape of the cylindrical body and a connective interlock is formed by the dove tail joint  24 ,  26  thereafter the ends  435 ,  437  are joined preferably by welding, clenching or brazing. 
         [0026]    Referring to  FIGS. 5-14 , a clutch housing  407  is provided. As shown, clutch housing  407  will support friction plates on its outer diameter but the clutch housing can be designed to mount friction plates on its inner diameter. Clutch housing  407  has a hub portion  440 . In many embodiments, the hub  440  will be fabricated from powered metal. Hub  440  has a disc or planer portion  442  integrally connected with a cylindrical portion  444  having internal spline teeth  446 . The hub  440  has a series of apertures  448  to allow for passage of rivet fasteners  450  that connects the hub  440  with the cylindrical body  410 . The hub  440  along its peripheral surface has a series of radially projecting gear like teeth  451 . Alternating teeth  451  have radial overhangs  452 . The radial overhangs  452  are continuous with radial ribs or vanes  454  that are formed by depressions  458  in an outer surface of the hub disc portion  442 . Cylindrical body spline teeth  414  have a series of axially alternating positioned oil slots  416 . The cylindrical body  410  has a generally axial portion  418  and radially inwardly bent tabs  420 . Between the generally axial portion  418  and the radially inwardly bent tabs  420  is a transition region  422 . Between the tabs  420  within the transition region  422 , there are slots  424 . Connecting the generally cylindrical body  410  with the hub  440  are a series of rivets  450 . The radial tabs  420  are aligned with the hub depressions  458  and the hub&#39;s radial gear like teeth  451  are aligned with the outer radial flat  417  of the spline teeth  414  of the cylindrical body  410 . Additionally, the gear teeth  451  aid in supporting the spline teeth  414  in the transition region  422 . The vanes  454  and their slot  424  received radial overhangs  452  provide for a circumferential interlock and torsional force transfer to the cylindrical body tabs  420 . In the transition region  422 , the aforementioned interlock inhibits a propagation of cracks in the cylindrical body  410 . 
         [0027]    Between the radially inward bent tabs  420  of the cylindrical housing and the disc portion  442  of the hub, there is a torsional interchange facilitated by the rivets  450  and a sheer mold. The tabs  420  lateral sides  471  have an interference fit with the vanes  454  to allow a torsional interchange in a compressive contact mode between the tabs  420  and the vanes  454 . Via the overhang  458  of the vanes  454  in the slot  424 , there is also a similar compressive torsional interchange between the cylindrical body and the hub in the transition region  422  of the cylindrical body. Typically the hub  440  is also connected to the cylindrical body  410  by the interference connection of the splined teeth  414  with the hub radially projecting gear like teeth  451 . Accordingly, a maximum amount of torsional interchange between the hub and cylindrical body is achieved while allowing the material utilized to fabricate the cylindrical body  410  to be as thin as possible while at the same time preventing tears in the material of the cylindrical body. Torsional interchange between the hub and cylindrical body is achieved along the main portion of the radial tab  420  along the peripheral edges of the tab  420  within the transition region  422  and with the circumferential interlock between the hub gear teeth  541  and the cylindrical body splined teeth  414  providing a strong and enduring joint between the hub and cylindrical body. 
         [0028]    The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.