Modular Assembly Having Press-Fit Fastener Holes

Abstract

A modular assembly having a press-fit fastener hole. The press-fit fastener hole may include a plurality of lobe regions and a plurality of contact regions that may be spaced between lobe regions for a press-fit engagement with a fastener. The fastener may have a first diameter and the contact regions collectively may define an imaginary second diameter that is less than or equal to the first diameter.

1 . A modular assembly having a press-fit fastener hole, the press-fit fastener hole comprising;
 a plurality of lobe regions; and   a plurality of contact regions spaced between lobe regions for a press-fit engagement with a fastener haying a first diameter, the contact regions collectively defining an imaginary second diameter that is less than or equal to the first diameter.   
     
     
         2 . The press-fit fastener hole of  claim 1 , wherein the press-fit fastener hole is located in a flange of the modular assembly. 
     
     
         3 . The press-fit fastener hole of  claim 2 , wherein the press-fit fastener hole has three lobe regions, the lobe regions defined by three overlapping ellipses. 
     
     
         4 . The press-fit fastener hole of  claim 2 , wherein each of the contact regions include a cusp. 
     
     
         5 . The modular assembly of  claim 2 , further comprising the fastener having a shank with the first diameter, wherein the shank is slidably received in the press-fit fastener hole, wherein when the shank is located in the press-fit fastener hole, the position and orientation of the fastener are retained. 
     
     
         6 . The modular assembly of  claim 5 , wherein the fastener shank has a plurality of male threads along its axial length engaging the contact regions, wherein the male threads are adapted to be both press-fit against the contact regions and afterwards be received by female threads. 
     
     
         7 . The modular assembly of  claim 5 , wherein the first diameter is 1-10% larger than the imaginary second diameter. 
     
     
         8 . The modular assembly of  claim 5 , wherein the orientation of the fastener shank with respect to the flange is retained within 5 degrees. 
     
     
         9 . The modular assembly of  claim 5 , further comprising a pan comprising the flange, wherein the pan is one of an oil pan, a transmission pan, a timing belt cover, a chain cover, a gear cover, a cam cover, or a valve cover. 
     
     
         10 . The press-fit fastener hole of  claim 1 , wherein the press-fit fastener hole is located within a spacer of the modular assembly. 
     
     
         11 . The modular assembly of  claim 10 , wherein when the fastener is located in the press-fit fastener hole of the spacer, the position and orientation of the fastener are retained. 
     
     
         12 . A modular assembly configured to be coupled to another component, comprising:
 a pan having a flange with at least one hole therethrough; and   at least one fastener press-fitted within the at least one hole,   wherein each of the at least one holes includes:
 a plurality of lobe regions, 
 and a plurality of contact regions, each contact region being located at an intersection of two or more lobe regions, wherein the press-fit engagement of the fastener and the hole is associated with an inner diameter of the hole as defined by the contact regions and an outer diameter of the fastener. 
   
     
     
         13 . The modular assembly of  claim 12 , wherein the contact regions are radially inwardly extending cusps. 
     
     
         14 . The modular assembly of  claim 12 , wherein the at least one fastener is configured for position and orientation retention within the hole until the modular assembly is fixedly coupled to the another component via the at least one fastener. 
     
     
         15 . The modular assembly of  claim 14 , wherein the orientation of a longitudinal axis of the fastener is retained with respect to the flange within 5 degrees.