Well I have been reading a bit about keeping the tracks adjusted ext. My question is simply, why don't the rubber track machines have some sort of hydraulic pressure apparatus that keeps the tracks properly adjusted? Basically the entire machine is a rolling hydraulic pump, so why are there not some sort of hydraulic cylinder that keeps the tracks at the proper tension? Even a hydraulic accumulator with a positive charge could make this task of adjusting the tracks a more simple chore. Ken
Some big excavators use an accumulator as a recoil spring. Basically charge the accumulator with nitrogen and then run one of the hydraulic functions over relief which sets the recoil pressure. They still use grease to do the final adjustment of the tracks. That system is great for a big machine that is frequently moved and the track frames have to be pushed in for loading on a low boy. There has to be enough slack in the tracks to be able to get to the bolts that hold the frames in place. The old Terex dozers also used an accumulator that pushed the idlers out and made the tracks tight. Then you put grease in the adjuster to push the idlers back to loosen the track for proper tension. Mini excavators don't really have enough room to mount an accumulator in the carbody and I think the recoil springs with the grease type adjusters are probably the most cost efficient and use the smallest amount of room. Add to that the adjusters are exposed constantly to dirt so a hydraulic leak in the track frame would be an expensive repair.
Some do. My Takeuchi TB180FR machines have hydraulic track tension adjusters. The simple answer is money. A grease jack is a lot less complex and involves significantly fewer parts. So, less to build and less to maintain.
OK, Thanks for the replies. I am now educated. . He who asks a question is a fool for 5 minutes. He who does not ask the question is a fool for life.