Patent ID: 8393986

Claim:
A pivoting chain tensioner arm assembly comprising: a one-piece molded polymeric tensioner arm comprising a cylindrical pivot bore defined by a cylindrical bore wall centered about a pivot axis about which said tensioner arm pivots during use, said cylindrical bore wall extending axially between and defining an inner end of said pivot bore that opens through a rear face of the tensioner arm and an outer end of said pivot bore that opens through a front face of the tensioner arm such that said cylindrical pivot bore extends between said rear face and said front face of said tensioner arm; said cylindrical bore wall comprising a plurality of pockets defined therein and that open radially through said cylindrical bore wall into said cylindrical pivot bore and that open through one of said rear and front faces of said tensioner arm, each said pocket comprising: (i) an outer wall that extends axially relative to said pivot axis; and, (ii) an end wall arranged transverse to said pivot axis; said tensioner arm further comprising a plurality of fastener retaining tabs, located respectively in said plurality of pockets, wherein each of said plurality of fastener retaining tabs extends axially from said transverse end wall of the respective pocket at a location spaced from said outer wall of the respective pocket so as to be spaced from said outer wall and selectively resiliently deflectable radially outward with respect to said pivot bore toward said outer wall, and wherein each of said plurality of fastener retaining tabs comprises a tip that projects radially inward relative to said cylindrical bore wall into said pivot bore; a shoulder bolt fastener extending through said pivot bore, said shoulder bolt fastener comprising a head, a flange, an unthreaded cylindrical shoulder region, and a threaded shank, said unthreaded cylindrical shoulder region closely received in said pivot bore and extending completely through said pivot bore when said flange of said fastener is abutted with said front face of said tensioner arm so that said tensioner arm is rotatable on said cylindrical shoulder region of said fastener about said pivot axis, wherein said unthreaded cylindrical shoulder region comprises a annular groove that extends completely circumferentially around said unthreaded cylindrical shoulder region, wherein the tip of each fastener retaining tab is located in said annular groove such that said plurality of fastener retaining tabs inhibit withdrawal of said shoulder bolt fastener from said pivot bore of said tensioner arm while said annular groove permits rotation of said tensioner arm relative to said unthreaded shoulder region of said shoulder bolt fastener when said tip of each fastener retaining tab is located in said annular groove.