Draft sensing elevating scraper with automatic elevator speed control

Abstract

A removal control system for a scraper having a tractor pivotally attached to a bowl, said bowl having a cutting blade attached thereto, an elevator pivotally mounted on said bowl, an engine and utilizing an elevator control system and a cutting depth control system either in combination or separately whereby the optimum removal rate is maintained during operation of said scraper. The elevator control system includes a variable speed drive mechanism operatively connected to said elevator and said engine for controlling the speed of said elevator, a motion sensing mechanism responsive to said elevator's pivotal motion for varying the speed of said variable speed drive mechanism, a connector operatively connecting said motion sensing mechanism and said variable speed drive mechanism, a speed selector arrangement operatively connected to said variable speed mechanism for establishing the optimum speed of said elevator and a linkage arrangement operatively connecting said variable speed drive mechanism and said selector arrangement. The cutting depth control system includes a position control mechanism operatively connected to said engine and a cutting blade adjustably mounted on said bowl for establishing the cutting depth of said blade, a draft sensing mechanism responsive to the cutting load on said scraper for varying the position of said position control mechanism, a coupling operatively connecting said draft sensing mechanism and said position control mechanism, a coupling operably connecting said draft sensing mechanism and said position control mechanism, a depth selector arrangement operably connected to said position control means for establishing the optimum cutting depth of said cutting blade and a lever arrangement operably connecting said depth selector mechanism and said position control mechanism.

Dependencies are inferred from the claim text.