Because the implement is essentially part of the tractor, every time the front end of the tractor goes up, the implement will want to dig deeper in the rear, and every time the front goes down it digs very shallow.įor many implements such as cultivators, this action is more of an inconvenience than a problem, but when plowing it becomes an unbearable nightmare. In fact, because of the weight transfer mentioned above, farmers didn’t have to invest as much of their money in larger tractors with wheel weights to accomplish the same amount of work.Īlthough we just discussed the incredible positives of three-point mounted machinery, there is one major negative. The implements were simpler, required no lifting mechanism and usually were lighter overall because they used less steel. Most importantly, the implement became part of the tractor’s weight meaning that a smaller, lighter tractor could pull a larger implement for its size.Īnother key feature of three-point mounted equipment was that it was generally cheaper than its drawbar mounted cousins. The tractor and implement could be raised while stationary and the implement could be backed up. They were not designed to be backed up at all and backing them up could bind them up to the point of breaking.Īnd possibly the most important, because traction is directly related to tractor weight, tractors were required to be heavy enough to create the traction required for tillage.īy creating the draft sensing three-point hitch Henry Ford and Harry Ferguson solved all three of these major problems. Second, implements such as gang disks and many three-bottom plows could not be backed up. My son, Will, running our 1948 Minneapolis-Moline UTU tractor and pulling a John Deere model 66 mechanical lift drag plow In the case of the draw plow, often the only option was to detach the tractor from the plow and try to pull it out backwards. These mechanical lifts worked fine in perfect conditions, but should the tractor get stuck they were incredibly difficult to deal with. Unfortunately, in the 1920’s and 30’s there was really only one way to attach machinery by the drawbar.ĭrawn machinery worked, but it had several limitations.įirst, because the tractors of the time did not have remote hydraulics, plows and other machinery required forward movement to actuate the mechanical lift.

I think that we take the three-point hitch for granted today because, for most of us, it has been around our entire lifetime. I know this post was supposed to be about draft control, but I couldn’t help throwing in this tidbit of info as well. Thanks to an argument over his patent, Ferguson began making his own tractors in 1948, and by the mid-1950s all American tractor manufacturers offered a utility tractor with draft sensing three-point hitch. Thanks to a handshake agreement, Henry Ford used Ferguson’s design to create an entirely new type of tractor that had worldwide appeal, the utility tractor.ĭraft control is the ability for a tractor to adjust the depth of its three-point hitch based on soil conditions and engine power output. What made the 1939 Ford 9N tractor revolutionary was the draft control system that had been designed by Harry Ferguson. It also minimizes operator fatigue and improves the operation efficiency resulting from a minimum intervention for depth and draft control under dynamic field conditions.Although the Ford 9N tractor is known for being the first widely sold tractor with an integrated three-point hitch, it was not the first. The novel intelligent slip-draft control system also amounted to improve the tractive performance of 9.17% and 6.05% during ploughing and harrowing respectively when analyzed against an existing draft control system. A maximum slip variation of 2% was witnessed between the computed and the indicated values in the developed system.

The developed system was evaluated with test tractor and analogized with the existing draft control system. Implement draft was recorded using a three-point linkage dynamometer placed between the tractor and implement. Actual and theoretical speeds were digitally acquired through the controller-Hall Effect combination employed on front and rear wheels for the digital accession of the wheel slip. The system synchronously measures and controls the wheel slip and implement’s draft closer to the set ranges under varying field conditions. A microcontroller-based embedded system for automatic slip-draft control was designed, developed and tested for a 2WD tractor.

Draft control on tractor