Power transmission system

A power transmission system that includes a rotatable and drivable first shaft which is adapted for coaction with a motor that forms part of a planetary gear arrangement, and a second shaft which is driven by said arrangement, wherein a planet gear belonging to the planet gear arrangement includes a centrally positioned sun gear that coacts with said first shaft, a number of planet gears able to coact with said sun gear, a ring gear coacting with said planet gears, and a gear holding said planet gears, and wherein an hydraulic system forming part of the planetary gear arrangement includes a pump unit and a motor unit, among other things, and wherein the ring gear belonging to the planetary gear mechanism can be braked via a first coupling unit and therewith held stationary relative to a chassis in a low speed range while being freed for rotation in a high speed range, wherein in the low speed range the hydraulic system functions to drive the second shaft with the pump unit and the motor unit but provides a split-torque function in the high speed range, characterized in that the first shaft is adapted to rotate the sun gear;

• in that said hydraulic pump unit is coupled directly or indirectly to the gear holding said planet gears;
• in that said hydraulic motor unit is coupled directly or indirectly to the second shaft;
• in that a second coupling unit functions to co-ordinate the rotary movement of the ring gear with the pivotal movements of the hydraulic motor in the high speed range;
• and in that in said low speed range said first shaft functions to drive said pump unit via the gear that holds or carries the planet gears and a gear connected to said planet gear carrier.

A power transmission system that includes a rotatable and drivable first shaft which is adapted for coaction with a motor that forms part of a planetary gear arrangement, and a second shaft which is driven by said arrangement, wherein a planet gear belonging to the planet gear arrangement includes a centrally positioned sun gear that coacts with said first shaft, a number of planet gears able to coact with said sun gear, a ring gear coacting with said planet gears, and a gear holding said planet gears, and wherein an hydraulic system forming part of the planetary gear arrangement includes a pump unit and a motor unit, among other things, and wherein the ring gear belonging to the planetary gear mechanism can be braked via a first coupling unit and therewith held stationary relative to a chassis in a low speed range while being freed for rotation in a high speed range, wherein in the low speed range the hydraulic system functions to drive the second shaft with the pump unit and the motor unit but provides a split-torque function in the high speed range, characterized in that the first shaft is adapted to rotate the sun gear;

• in that said hydraulic pump unit is coupled directly or indirectly to the gear holding said planet gears;
• in that said hydraulic motor unit is coupled directly or indirectly to the second shaft;
• in that a second coupling unit functions to co-ordinate the rotary movement of the ring gear with the pivotal movements of the hydraulic motor in the high speed range;
• and in that the motor unit included in the hydraulic system is set to zero and freely rotatable in a position for the higher speed adjustment;
• in that the pump unit is therewith latched and stands stationary, wherein rotary movement of the first shaft is transferred to the second shaft via the sun gear, planet gears and ring gear.

A power transmission system that includes a rotatable and drivable first shaft which is adapted for coaction with a motor that forms part of a planetary gear arrangement, and a second shaft which is driven by said arrangement, wherein a planet gear belonging to the planet gear arrangement includes a centrally positioned sun gear that coacts with said first shaft, a number of planet gears able to coact with said sun gear, a ring gear coacting with said planet gears, and a gear holding said planet gears, and wherein an hydraulic system forming part of the planetary gear arrangement includes a pump unit and a motor unit, among other things, and wherein the ring gear belonging to the planetary gear mechanism can be braked via a first coupling unit and therewith held stationary relative to a chassis in a low speed range while being freed for rotation in a high speed range, wherein in the low speed range the hydraulic system functions to drive the second shaft with the pump unit and the motor unit but provides a split-torque function in the high speed range, characterized in that the first shaft is adapted to rotate the sun gear;

• in that said hydraulic pump unit is coupled directly or indirectly to the gear holding said planet gears;
• in that said hydraulic motor unit is coupled directly or indirectly to the second shaft;
• in that a second coupling unit functions to co-ordinate the rotary movement of the ring gear with the pivotal movements of the hydraulic motor in the high speed range;
• and in that said first and/or second coupling unit can be activatable and de-activatable via a valve arrangement belonging to an hydraulic system.