Crankshaft damper with integral pulse ring and method

Abstract

The invention comprises a crankshaft damper having an integral pulse ring. The crankshaft damper comprises an inner hub and outer pulley with an elastomeric connecting member between each. The elastomeric ring dampens a crankshaft vibration. The integral pulse ring is manufactured as part of the inner hub by flow forming a sheet metal blank.

We claim:  
     
         1 . A damper comprising: 
 an inner member having an outer substantially cylindrical surface;    an outer member having an inner substantially cylindrical surface;    the inner member outer surface and the outer member inner surface joined by a flexible connecting member;    the inner member further comprising an integral radially extending member, the integral radially extending member having a plurality of spaced tabs extending about an outer perimeter of the inner member.    
     
     
         2 . The damper as in  claim 1 , wherein the inner member further comprises a hub for engaging a shaft.  
     
     
         3 . The damper as in  claim 2 , wherein the outer member further comprises a belt bearing surface having a profile.  
     
     
         4 . The damper as in  claim 3 , wherein the belt bearing surface comprises a multi-ribbed profile.  
     
     
         5 . The damper as in  claim 2 , wherein the hub further describes a bore for engaging a shaft.  
     
     
         6 . The damper as in  claim 1 , wherein the flexible connecting member comprises an elastomeric material.  
     
     
         7 . The damper as in  claim 1  further comprising a discontinuity subject to detection by a sensor.  
     
     
         8 . The damper as in  claim 7 , wherein the discontinuity comprises a gap between adjacent tabs.  
     
     
         9 . A method of forming a crankshaft damper comprising: 
 forming a first ring by spinning a first annular disc supported in a rotating mandrel, moving a first roller radially inwardly against a side of the first disc displacing a portion of the first disc inwardly against a mandrel to form a hub, pressing a second roller radially inwardly against a first annular disc edge whereby a gathered portion of the first annular disc is formed, splitting the gathered portion by inward radial movement of a roller while simultaneously forming a lobe from the gathered portion, stretching the lobe in a radial direction by outward radial movement of a second roller while simultaneously supporting a portion of the gathered portion, thereby simultaneously forming a radially extending member substantially normal to an axis of rotation of the first ring;    forming a plurality of tabs extending about a perimeter of the radially extending member;    forming a second ring by spinning a second annular disc supported in a rotating mandrel, moving a first roller radially inwardly against a second annular disc edge whereby a gathered portion of the second annular disc is formed, pressing a roller having a profile against the gathered material whereby a profile is formed in a second ring outer surface; and    connecting the first ring to the second ring by engaging a flexible connecting member between the first ring and the second ring.    
     
     
         10 . The method as in  claim 9 , wherein the connecting member comprises an elastomeric material.  
     
     
         11 . The method as in  claim 9  further comprising forming a profile in the first ring outer surface and forming a profile in the second ring inner surface to cooperate with the first ring outer surface profile.  
     
     
         12 . The method as in  claim 10 , comprising forming a multi-ribbed profile in the second ring outer surface.  
     
     
         13 . The method as in  claim 9  comprising stamping to form the tabs.  
     
     
         14 . The method as in  claim 9  comprising forming a gap in the tabs.