Combines CVT OR THE MASSEY DRIVE

[John_W]

As I understand things the Massey has a basic hydrostat drive on the rotor with electronics control to keep it operating at a constant speed. CIH is using a CVT which is a continously variable transmission. And a CVT is basically a planetary transmission that uses a hydrostat arrangement to control its output speed. With a CVT all the power is not transmitted via the oil as in a hydrostat pump_motor lash up. Here is how Fendt describes their CVT transmission which they call a Vario. "The Vario transmission is composed of two elements, a hydraulic drive section and mechanical drive sections, which work together to provide the right match of speed and torque. As engine power reaches the transmission it is split by a planetary gear and directed at a constant ratio to either the mechanical drive unit by the sun gear, or to the hydrostatic unit via the ring gear. The engine power is applied to the planetary gear set via that planet gear carrier. At low speeds and start up, the major part of the engine output is directed to the hydrostatic unit, which consists of a hydraulic pump and two hydraulic motors, with a unique displacement angle of 45 degrees. However, the higher the speed of the tractor the more of the tractive power shifts to the mechanical portion of the transmission and away from the hydrostatic portion. Here, the residue torque is transmitted via pinions to the collecting shaft where the torque values of the hydrostatic and mechanical drive trains are added together. To achieve maximum efficiency at low speeds and high power requirements in the field, as well as fast transport speed on the road, the Vario transmission has two speed ranges. Range 1 goes from 0.1 to 20 mph forward and 0.1 to 13 in reverse. Range II provides speeds from 0.1 to 31 mph forward and 0.1 to 24 mph in reverse. To change from one range to the other the driver only needs to press the range control button next to the joystick any time the tractor is within appropriate speed limitations." This info is paraphrased from a Fendt brochure. There, clear as mud, rightIJ

 

[silver_dollar_salo]

murky waters--but ok. like another poster said we'll wait and see what deere does with the same concept and then it will be proven worthy for the msrketplace.

 

[G_Man_Red]

Sure because you no Deere has never made any mistakes. Have theyIJ

 

[G_Man]

I think you have it backwards - when it's proven to work properly - Deere will do it! Of course the STS isn't a rotary is itIJ

 

[G_Man_Red]

Yes I did have it backwards. My apologies.

 

[harolddog]

I thought STS stood for Same Thing Stupid

 

[RedHat]

The MF(White) rotor drive system is a 100% hydrostatic drive with a planetary drive bolted on the end for increased torque. It is only about 80% efficient, typical of hydro systems. The CVT in the 8010 is a 100% mechanical drive with a hydraulic motor attached to a sun gear_planetary system to allow speed changes. The speed is changed when the hydraulic motor on the sun gear rotates with or against the rotation of the output shaft of the CVT. It allows 20% up or down speed change. Now, when a clutch is locked up in the CVT and no input shaft power is supplied just the hydraulic motor turns forward or backward by the operator in the cab and that is what gives the 8010 a feeder_rotor reverser or de-slug as they call it. This system is only similar to the Fendt system in that the speed is controlled by a hydraulic motor.