Root crop harvester

A sugar beet harvester apparatus, comprising:

• a wheeled frame, configured to move along a ground;
• a plurality of pairs of axles attached to the wheeled frame, each pair of axles including a first axle and a second axle;
• a plurality of pairs of generally upright, spaced apart, symmetrically non-parallel puller wheels, each pair of puller wheels including a first puller wheel and a second puller wheel, the first puller wheels associated with the first axles and the second puller wheels associated with the second axles, each of the puller wheels of the pair of puller wheels having a rim configured for cutting into the ground, each pair of puller wheels having a rearward portion with a minimum gap therebetween;
• and
• a pair of gap adjusters associated with each pair of puller wheels, including a first gap adjuster associated with the first puller wheel and a second gap adjuster associated with the second puller wheel,
• the first gap adjuster including a first collar, slidably disposed upon the first axle, and including a first helical surface and a first bearing surface, the first helical surface and the first bearing surface being in sliding contact, the first collar including one of the first helical surface and the first bearing surface, and the first axle including the other of the first helical surface and the first bearing surface, the first puller wheel being rotatably attached to the first collar, axial rotation of the first collar about the first axle causing lateral translation of the first collar and attached first puller wheel by sliding contact between the first helical surface and the first bearing surface, and
• the second gap adjuster including a second collar, slidably disposed upon the second axle, and including a first helical surface and a first bearing surface, the first helical surface and the first bearing surface being in sliding contact, the second collar including one of the first helical surface and the first bearing surface, and the second axle including the other of the first helical surface and the first bearing surface, the second puller wheel being rotatably attached to the second collar, axial rotation of the second collar about the second axle causing lateral translation of the second collar and attached second puller wheel by sliding contact between the first helical surface and the first bearing surface, whereby a magnitude of the minimum gap is selectively adjustable.

A sugar beet harvester apparatus, comprising:

• a plurality of pairs of generally upright, spaced apart, symmetrically rearwardly canted puller wheels, disposed in a transverse row, each puller wheel of each pair of puller wheels having an axle and a rim configured for cutting into ground, each pair of puller wheels having a minimum gap in a rearward region;
• and
• a plurality of pairs of rotatable collars, each puller wheel being rotatably attached to a respective rotatable collar of the plurality of pairs of rotatable collars, each rotatable collar having helical bearings at opposite ends thereof, axial rotation of the rotatable collar upon its respective axle causing lateral translation of the rotatable collar and the attached puller wheel, whereby a magnitude of the minimum gap is selectively adjustable,
• wherein each of the helical bearings comprises a helical surface and a bearing surface, wherein sliding contact between the helical surface and the bearing surface moves the rotatable collar and attached puller wheel axially along the axle with axial rotation of the rotatable collar.