Automatic height control for a harvester header

摘要

A self-propelled combine harvester is equipped with a grain cutting platform having a floating, flexible cutter bar. The operating height of the grain platform is controlled conventionally by hydraulic cylinders. An automatic operating mode may be chosen in which the hydraulic cylinders are responsive to a signal corresponding to vertical disposition of the floating cutter bar relative to the floor of the platform. The automatic control system includes a sealed self-contained position sensor switch module directly coupled to a sensor rock shaft whose rotational position in the platform frame is representative of the disposition of the cutter bar relative to the platform floor. The sensor switch module includes a segmented printed circuit board and an associated wiper arm with a brush assembly, directly coupled to the sensor shaft. Selector switching means includes a rotary switch at the operator station which the operator can set to control the platform at any one of three operating height set points. A mechanical float range indicator is optionally provided.