Patent ID: 7121073

Claim:
A control system for adjusting the reel of a cutting reel unit, comprising: a cutting reel; a frame supported on at least one support element that is supported on, and is movable along, the ground; at least one housing supporting said cutting reel, said housing movably mounted on said frame; a bedknife carried on said frame; an actuator having a first portion connected to the frame and a second portion connected to said housing, wherein relative positions of said first and second portions are adjustable to set a pre-selected clearance between said reel and said bedknife, and including a motive mechanism that is activated to adjust said relative positions; and a controller signal-connected to said motive mechanism to set said pre-selected clearance; comprising a precise position sensor, said precise position sensor signal-connected to said controller, said controller signal-connected to said motive mechanism to precisely adjust said relative positions based on a position signal from said sensor; wherein said motive mechanism comprises a stepper motor, and said sensor comprises an optical encoder having a read head signal-connected to said controller and an optical disk arranged to rotate with an output shaft of said stepper motor.