Temperature and pressure compensated geared traction unit

A geared torque transfer device comprising;

• a housing;
• an input sun gear rotatably supported in the housing;
• an output sun gear rotatably supported in the housing;
• a plurality of planet gears rotatably supported in the housing and in mutual engagement with the input and output sun gears;
• a quantity of viscous fluid disposed with the housing;
• means for defining a fluid flow path such that rotation of the planet gears causes the viscous fluid to flow through the fluid flow path;
• and
• means responsive to the pressure of the viscous fluid for restricting the free flow of fluid through the flow path thereby creating resistance to the rotation of the planet gears and housing in response to differences in rotational velocity of the input and output sun gears whereby torque is transferred between the input and output sun gears.

A geared torque transfer device comprising;

• a housing;
• an input sun gear rotatably supported in the housing;
• an output sun gear rotatably supported in the housing;
• a plurality of planet gears rotatably supported in the housing and in mutual engagement with the input and output sun gears;
• a quantity of viscous fluid disposed with the housing;
• means for defining a fluid flow path such that rotation of the planet gears causes the viscous fluid to flow through the fluid flow path;
• and
• means responsive to the temperature and pressure of the viscous fluid for restricting the free flow of fluid through the flow path thereby creating resistance to the rotation of the planet gears and housing in response to differences in rotational velocity of the input and output sun gears whereby torque is transferred between the input and output sun gears.