Split torque transmission
AssigneeTransmission Research, Inc.
InventorGraham White
Life of this patent
Estimating the term…
Abstract
A split-torque transmission in which a high-speed engine drives a substantially lower speed drive shaft, such as a helicopter rotor drive shaft, comprises a pair of selectively laterally inclined cross shafts for drivingly connecting a corresponding pair of helicopter engines with the helicopter rotor drive shaft. The transmission arrangement achieves a relatively high overall speed reduction, such as required in the transmission of power to the main rotor of a helicopter, with a minimum number of reduction stages, gears, and bearings. The lateral inclination of the cross shafts and the adjustable positioning of the associated gears to vary that inclination permits the engines of a two or more engined helicopter to be relatively widely separated and at the same time compact the drive arrangement in the longitudinal direction.
Claims16
in a helicopter having a main rotor drive shaft rotatable about a vertical axis and two parallel-mounted engines for powering said rotor drive shaft, a drive transmission for connecting said engines to said rotor drive shaft such that said engines are variably laterally separated from one another comprising:
- respective input shafts driven by said engines, respective cross shafts connected to said input shafts at lead ends thereof and laterally angled relative to the longitudianl axis of said helicopter such that tail ends thereof are closer to said vertical axis than said lead ends,
- respective drive pinion means powered from the tail ends of said cross shafts, and a combining gear secured to said rotor drive shaft and powered by said drive pinions spaced about the circumference thereof, the tail ends of said cross shafts being able to extend to said respective drive pinion means at various lateral angles for adjustment of the lateral separation of said engines.
A drive transmission, intended primarily for helicopters, disposed between a relatively high speed rotary engine horizontally directed input and a relatively low speed vertically directed rotary drive output comprising a first reduction gear powered by said engine input, a torque divider means connected to said first reduction gear and having first and second torque outputs, a cross shaft powered by said torque divider means and being laterally inclined relative to the axis of rotation of said engine input, said cross shaft having a respective first pinion engaged by said first torque output and a second pinion engaged by said second torque output, a pair of second reduction gears respectively powered by said first and second pinions and receiving equal torques, final drive pinions fixedly secured to said second reduction gears, and a combining reduction gear engaged by said final drive pinions, said combining reduction gear secured to said drive output.
A split-torque transmission system adapted to connect a substantially horizontally oriented engine to a substantially vertically oriented drive shaft to be driven thereby at a substantially reduced rotary speed comprising:
- a first reduction gear driven by said engine,
- a planetary gear-type torque divider connected to said first reduction gear having first and second unequal torque outputs,
- a cross shaft formed with coaxial first and second drive pinions respectively powered by said first and second torque outputs, said cross shaft being laterally inclined relative to the longitudinal axis of said engine,
- a pair of second reduction gears respectively driven by said first and second pinions and each having a final drive pinion secured thereto, and a third reduction gear secured to said drive shaft and powered by said final drive pinions being spaced thereabout.
Dependencies are inferred from the claim text.