Home / Technology Innovation / EST Technology EST (For Environment & Energy-efficiency, Spontaneous Stepless Transmission) EST is a variable transmission. It changes the rotary motion of the power source into the reciprocating motion and generates output in the rotary power according to on the change in the angle of the reciprocating motion. Depending on the input and output conditions, the angle of the reciprocating motion is automatically changed so without a separate gear control system, gear is automatically, steplessly changed. Method of gear change : Stepless gear change Range : 0 ~ Infinity Direction change : Possible to change into the right direction and the reverse direction;      Auto stepless gear change for both directions Energy efficiency : High efficiency   Gear control : A gear control device is not necessary.   Performance of transmission : Possible to transmit large power Safety : Automatically coping with overload Automatically preventing Voluntary gear section setting : Possible to be set by users (option)   Item Overview Transmitting power with hydraulic pressure energy Transmitting power with fixed reduction gear ratio Transmitting power with infinite gear ratio Type of power transmission Working oil -> Actuator Gear Gear , Rod Capacity of power transmission Transmitting large power Transmitting large power Transmitting large power Startup Proper operation Fixed rpm startup Variable rpm startup Normal operation Classified into positive displacement and variable displacement type Working at fixed rpm all the time Working at the set rpm within the proper load; rpm ↓, output torque ↑ at overload Energy consumption Different by type Consuming overcurrent depending on load Flexibly consuming proper current Transmission of overload Different by type Startup load and overload are transmitted to the power source. Startup load and overload are not transmitted to the power source. It copes with auto stepless gear change. Protection of power source Different by type Impossible Possible Efficiency The efficiency of power transmission is low. -Power loss in the hydraulic pump -Power loss in the pipe -Power loss in the control valve -Power loss in the actuator -Power loss by the change in the viscosity of hydraulic oil The higher the reduction gear ratio is, the lower the efficiency of power transmission is. Highly-efficient power transmission is possible regardless of the stepless gear range. Durability There are many factors that can lower durability. -Change in the temperature of the hydraulic oil and its pollution -Shortage of oil quantity and pressure -Leaks of pipes and packings -Wear -Broken valves -Foreign materials mixed -Electric and electronic precise control -Limitation of the lifetime of other consumables Drop in the durability caused by load change Gear teeth wear and impact wear Having stable durability against load change, protecting the power source, and lengthening lifetime Output adjustment Through the control valve Impossible Auto adjustment without gear control Prevention of reverse rotation Possible None Auto prevention of reverse rotation Direction change Possible Possible Possible Size Big Average Average Noise Big Average Average Type Hydraulic unit system GearedMotor, Linepower GearedMotor, Linepower Mounting In unit Vertical , Horizontal Vertical , Horizontal Structure Oil tank, Hydraulic pump, Control valve, Actuator, Others Gear Box + Power source Gear Box Gear Box + Power source Gear Box Management Management of operating oil, consumables, filters, and the whole system General management of gearbox General management of gearbox Application Machinery industry Machinery industry Machinery industry   Item Development focus For vehicles For vehicles All the mechanical factors Variator Belt and variable pooley Traction tooler and toroidal Cam and Rod Type of power transmission Frictional force of belt and variable pooley Shear force of the lubricant by the rolling contact of a body of rotation Gear power transmission by the change in the rod angle Capacity of power transmission Low High High Efficiency High High High Gear ratio Restricted range Restricted range 0 ~ Infinity Gear control Gear control through the control system Gear control through the control system Auto gear control in EST itself based on the change in the rpm of the power source and the change in the output load, without a gear control system Size Average Big Average Weight Average Big Average Noise Average Low Low Durability Average Low High