Patent ID: 6179316
Filing Date: 2001-01-30
Classification: B62D

Abstract:
A fifth wheel hitch comprising:a top plate having a bifurcated rear forming a pair of rearwardly extending potions astraddle a tapered entering mouth and a dead-end throat for receiving a cooperative kingpin;a hinged jaw adjacent said throat, pivotally mounted to said top plate and pivotal between a closed position across said throat and an open position clear of said throat;said jaw having a rear surface for engagement by a locking plunger;a locking plunger having a front abutment surface, and being shiftable between a retracted unlocking position out of engagement with said jaw, and an extended fully locking position behind said jaw and with said abutment surface engageable with said jaw rear surface, said locking plunger being spring biased toward said locking position;wedge mechanism engaging said locking plunger for adjusting the forward-rearward position of said locking plunger to accommodate wear of said jaw;said wedge mechanism having a fixed wedge element with a forwardly sloped wedge surface, a movable wedge element having a rearwardly sloped wedge surface engaging said forwardly sloped wedge surface, and an adjuster for said movable wedge element relative to said fixed wedge element to thereby control the forward position of said movable wedge element;said jaw rear surface having a first rear surface portion and a second rear surface portion rearwardly offset from said first rear surface portion;said plunger abutment surface having a first front surface portion and a second front surface portion rearwardly offset from said first front surface portion;said first and second rear surface portions of said jaw being engageable with said respective first and second front surface portions of said plunger in full locking engagement of said locking plunger with said jaw, and said first front surface portion of said plunger being engageable with said second rear surface portion of said jaw if said plunger cannot shift to full locking engagement due to overadjustment of said wedge mechanism.