Patent ID: 8261523

Claim:
A reel cutting unit, which comprises: (a) a reel having a plurality of transversely extending blades that are spaced apart around a circumference of the reel, the reel being rotatable about a substantially horizontal axis; (b) a bedknife that is located adjacent the reel and that is cooperable with the reel to cut grass as the blades of the reel sweeps uncut grass against a cutting edge on the bedknife, wherein the rotation of the reel produces a clip that comprises a forward distance of travel of the cutting unit in a time interval determined by the length of time that it takes for successive blades on the reel to contact a predetermined reference spot on the bedknife; (c) a clip control and selection system for selecting one of a predetermined number of different possible clips when the reel cutting unit is propelled over the ground at a substantially constant ground speed, which comprises: (i) a drive shaft, a driven shaft, and an idler shaft that mount, respectively, a circular drive member, a circular driven member, and a circular idler member, each of the circular members having a different diameter from the other circular members; (ii) a flexible and endless transmission member entrained around the drive and driven members to transfer rotation of the drive shaft to the driven shaft with the driven shaft being operatively connected to the reel to rotate the reel, the idler member also engaging with the endless transmission member; and (iii) wherein the drive, driven and idler shafts are sufficiently similar in outside diameter to one another, and the drive, driven and idler members have mounting bores that are sufficiently similar in inside diameter to one another, that any of the drive, driven and idler members can be interchangeably mounted at any given time on any of the drive, driven and idler shafts to provide six different possible clips for selection by a user for a given constant rotational input speed of the drive shaft.