同济大学：《汽车构造》课程电子教案（课件讲稿）Hydro-mechanical Transmission and Continuously Variable Transmission

Hydro-mechanical Transmission and Continuously Variable Transmission

Hydro-mechanical Transmission and Continuously Variable Transmission

Hydro-mechanical transmission and continuously variable transmission ☐Main content 1.The working principle of hydraulic coupler and hydrodynamictorque converter 2.The structure and principle of hydro- mechanical transmission 3.The control mechanism of automatic transmission 4.Continuous variable transmission

Hydro-mechanical transmission and continuously variable transmission Main content 1. The working principle of hydraulic coupler and hydrodynamic torque converter 2. The structure and principle of hydro￾mechanical transmission 3. The control mechanism of automatic transmission 4. Continuous variable transmission

The development of hydraulic transmission In the early 20th century,a ship with high power and high speed turbine needs high power reduction gear to match with the propeller,and gear manufacturing technology can't meet the requirements.So German professor Gell-Mann Fottinger put forward a hydraulic loop transmission system consisting of tank,centrifugal pump,water pipe and hydroturbine; .Using the pump impeller and turbine with blades to substitute centrifugal pump and hydroturbine ,the tank and water pipe canceled,forming a hydrodynamic torque converter which had a co-working liquid circulation chamber; .German passenger ship Chellebitz'once used hydrodynamic torque converter .Afterwards,marine gear reducer replaced marine hydrodynamic torque converter,and hydrodynamic torque converter began using on the car .In the 1970 s,More than 90%of the cars,100%of the bus and 70%of the heavy duty vehicles and off-highway vehicles applied hydrodynamic torque converter in America.The major car companies in the world are producing hydraulic transmission two-gear,three-gear or four-gear automatic transmission at present

The development of hydraulic transmission • In the early 20th century, a ship with high power and high speed turbine needs high power reduction gear to match with the propeller, and gear manufacturing technology can’t meet the requirements . So German professor Gell-Mann Fottinger put forward a hydraulic loop transmission system consisting of tank , centrifugal pump, water pipe and hydroturbine; •Using the pump impeller and turbine with blades to substitute centrifugal pump and hydroturbine ,the tank and water pipe canceled, forming a hydrodynamic torque converter which had a co-working liquid circulation chamber; •German passenger ship ‘Chellebitz’ once used hydrodynamic torque converter ; •Afterwards, marine gear reducer replaced marine hydrodynamic torque converter , and hydrodynamic torque converter began using on the car ； •In the 1970 s , More than 90% of the cars, 100% of the bus and 70% of the heavy duty vehicles and off-highway vehicles applied hydrodynamic torque converter in America. The major car companies in the world are producing hydraulic transmission + two-gear, three-gear or four-gear automatic transmission at present

The position of vehicle hydraulic torque converter in the transmission 液力支矩器 前置后驱动液力自动变速器 变矩器 HE168 www.c h a 168.c o m 行星齿轮变速 液力变拒器外壳

 The position of vehicle hydraulic torque converter in the transmission

Basic components of vehicle torque converter 导轮 CHE168 泵轮 涡轮 www.che168.com

Basic components of vehicle torque converter

Section one Hydro-mechanical transmission l、Hydraulic coupler Hydraulic coupler is a kind of hydrodynamic unit.Hydrokinetic transmission is a hydraulic transmission that using the change of liquid's kinetic energy in circular flow process to transmit dynamic. 液力耦合器与液力 变矩器 液力耦合器结构与工作原理 结构 1-壳体2-涡轮3-泵轮

Section one Hydro-mechanical transmission Hydraulic coupler is a kind of hydrodynamic unit. Hydrokinetic transmission is a hydraulic transmission that using the change of liquid’s kinetic energy in circular flow process to transmit dynamic. 1、 Hydraulic coupler

1.1 The structure and working principle of hydraulic coupler Gap (3-4mm Active component: impeller Pump Pump impeller impeller 3 Turbine Pump impeller 3 joints with coupler's body 2 and Body crankshaft 1 rigidly,and rotates with crankshaft. Crank- Output shaft shaft Driven member (impeller)turbine 4 Turbine 4 links with output shaft,installed in the sealed body. Pump impeller 3 and turbine 4: They are called working wheel

Crank￾shaft Body Pump impeller Turbine Output shaft 1.1 The structure and working principle of hydraulic coupler Active component： （ impeller ）Pump impeller 3 Driven member ： （impeller）turbine 4 Pump impeller 3 joints with coupler’s body 2 and crankshaft 1 rigidly，and rotates with crankshaft. Turbine 4 links with output shaft, installed in the sealed body. Pump impeller 3 and turbine 4： They are called working wheel Gap（ 3-4mm ）

Pump impeller 3 Turbine 风

Pump impeller Turbine

The same number of blades weld on the radial direction of pump impeller and turbine to transmit power After pump impeller and turbine assembled,the vertical section through the input shaft or output shaft is a ring,which is called torus section.The liquid to transfer power is driven by pump impeller's blade and does rotary motion around the axis.The liquid flows to the blade tip and it's speed increases under the action of the centrifugal force.The speed depends on the speed of the crankshaft and the radius of working wheel.The kinetic energy of the liquid increases after pressure rising by hit the wall', and rushes at turbine's blade to drive turbine rotating Afterwards,the kinetic energy of the liquid decreases and a dynamic fluid circulation from the high energy region to the low energy region forms.That is liquid rushes from the outer edge of pump impeller to turbine and forms a end- to-end spiral

The same number of blades weld on the radial direction of pump impeller and turbine to transmit power . After pump impeller and turbine assembled, the vertical section through the input shaft or output shaft is a ring, which is called torus section. The liquid to transfer power is driven by pump impeller’s blade and does rotary motion around the axis. The liquid flows to the blade tip and it’s speed increases under the action of the centrifugal force. The speed depends on the speed of the crankshaft and the radius of working wheel. The kinetic energy of the liquid increases after pressure rising by ‘hit the wall’, and rushes at turbine’s blade to drive turbine rotating . Afterwards, the kinetic energy of the liquid decreases and a dynamic fluid circulation from the high energy region to the low energy region forms. That is liquid rushes from the outer edge of pump impeller to turbine and forms a end￾to-end spiral

Conclusion: The working process of hydraulic coupler Pump impeller receives the mechanical energy from the engine and transfers it to the working fluid,so the kinetic energy of working fluid increases.Then the kinetic energy of working fluid transfers to the turbine to realize the power output. The necessary conditions of hydraulic coupler to realize transmission: There is a liquid circulation flow between pump impeller and turbine, the reason why there is a liquid circulation flow is that existing speeds difference between the two.So pump impeller's speed is always higher than turbine's when hydraulic coupler is working. The working principle of hydraulic coupler When the kinetic energy of flowing liquid changes,it will absorb or release energy

Conclusion： The working process of hydraulic coupler : Pump impeller receives the mechanical energy from the engine and transfers it to the working fluid, so the kinetic energy of working fluid increases. Then the kinetic energy of working fluid transfers to the turbine to realize the power output. The necessary conditions of hydraulic coupler to realize transmission: There is a liquid circulation flow between pump impeller and turbine, the reason why there is a liquid circulation flow is that existing speeds difference between the two. So pump impeller’s speed is always higher than turbine’s when hydraulic coupler is working. The working principle of hydraulic coupler ： When the kinetic energy of flowing liquid changes, it will absorb or release energy