25-04-2011, 12:40 PM
Submitted by:
VIJAY KUMAR
Automatic Transmission System ppt.ppt (Size: 1.32 MB / Downloads: 546)
INTRODUCTION
The modern automatic transmission is by far, the most complicated mechanical component in today’s automobile.
Automatic transmissions contain Mechanical systems, Hydraulic systems, Electrical systems and Computer controls, all working together in perfect harmony which goes virtually unnoticed until there is a problem.
WHAT IS TRANSMISSION ?
The transmission is a device that is connected to the back of the engine and sends the power from the engine to the drive wheels
Purpose of the transmission is to provide high torque at the time of starting the engine, hill climbing , accelerating and pulling a road.
TYPES OF AUTOMATIC TRANSMISSION
Rear wheel drive
Front wheel drive
REAR WHEEL DRIVE
The transmission is usually mounted to the back of the engine.
Power flow on this system is simple and straight forward going from the engine, through the torque converter, then through the transmission and drive shaft until it reaches the final drive where it is split and sent to the two rear wheels.
Example of rear wheel – Alpha Romeo Alfeta in early 70’s
REAR WHEEL DRIVE
FRONT WHEEL DRIVE
On a front wheel drive car, the transmission is usually combined with the final drive to form what is called a transaxle.
Transaxle is a device set up in the transmission gear box, clutch, final drive, combined into a single unit.
. Front-wheel-drive layouts are those in which the front wheels of the vehicle are driven. The most popular layout used in cars today is the front-engine, front-wheel drive, with the engine in front of the front axle, driving the front wheels.
This layout is typically chosen for its compact packaging.
Front axles are connected directly to the transaxle and provide power to the front wheels.
FRONT WHEEL DRIVE
TRANSMISSION COMPONENTS
Planetary Gear Sets
Hydraulic System
Oil Pump
Valve Body
Clutches
Band
Seals and Gaskets
Torque Converter
Governor
Computer Controls
PLANETARY GEAR SETS
SIDE VIEW
CLUTCH PACKS
BANDS
A band is a steel strap with friction material bonded to the inside surface.
One end of the band is anchored against the transmission case while the other end is connected to a servo.
TORQUE CONVERTER
HYDRAULIC SYSTEM
The Hydraulic system is a complex maze of passages and tubes that sends transmission fluid under pressure to all parts of the transmission and torque converter
It works with some components.
Oil Pump
Valve Body
COMPUTER CONTROLS
The computer uses sensors on the engine and transmission to detect such things as throttle position, vehicle speed, engine speed, engine load, brake pedal position, etc. to control exact shift points as well as how soft or firm the shift should be. Once the computer receives this information, it then sends signals to a solenoid pack inside the transmission
NON-COMPUTERIZED TRANSMISSIONS
Governor
Vacuum Modulator
Throttle Cable
Seals and Gaskets
SPOTTING PROBLEMS BEFORE THEY GET WORSE
Watch for leaks or stains under the car.
Check fluid for color and odor.
Be sensitive to new noises, vibrations and shift behavior.
TRANSMISSION REPAIRS
Adjustments and In-Car Repairs
Reseal job
Replace accessible parts
Complete Overhaul
Replacement unit vs. overhaul existing unit
Conclusion
Being able to drive a stick-shift means more than just understanding your gears, however. That's because to shift gears, you usually don't just move the shift lever and be done with it. (You can do this sometimes, but it's not recommended in day-to-day driving, and we'll get to it later.) Instead, you have to press the clutch pedal while you shift. . Keeping the transmission and its fluid cool, and in the correct operating-temperature range is crucial for long life.
VIJAY KUMAR
Automatic Transmission System ppt.ppt (Size: 1.32 MB / Downloads: 546)
INTRODUCTION
The modern automatic transmission is by far, the most complicated mechanical component in today’s automobile.
Automatic transmissions contain Mechanical systems, Hydraulic systems, Electrical systems and Computer controls, all working together in perfect harmony which goes virtually unnoticed until there is a problem.
WHAT IS TRANSMISSION ?
The transmission is a device that is connected to the back of the engine and sends the power from the engine to the drive wheels
Purpose of the transmission is to provide high torque at the time of starting the engine, hill climbing , accelerating and pulling a road.
TYPES OF AUTOMATIC TRANSMISSION
Rear wheel drive
Front wheel drive
REAR WHEEL DRIVE
The transmission is usually mounted to the back of the engine.
Power flow on this system is simple and straight forward going from the engine, through the torque converter, then through the transmission and drive shaft until it reaches the final drive where it is split and sent to the two rear wheels.
Example of rear wheel – Alpha Romeo Alfeta in early 70’s
REAR WHEEL DRIVE
FRONT WHEEL DRIVE
On a front wheel drive car, the transmission is usually combined with the final drive to form what is called a transaxle.
Transaxle is a device set up in the transmission gear box, clutch, final drive, combined into a single unit.
. Front-wheel-drive layouts are those in which the front wheels of the vehicle are driven. The most popular layout used in cars today is the front-engine, front-wheel drive, with the engine in front of the front axle, driving the front wheels.
This layout is typically chosen for its compact packaging.
Front axles are connected directly to the transaxle and provide power to the front wheels.
FRONT WHEEL DRIVE
TRANSMISSION COMPONENTS
Planetary Gear Sets
Hydraulic System
Oil Pump
Valve Body
Clutches
Band
Seals and Gaskets
Torque Converter
Governor
Computer Controls
PLANETARY GEAR SETS
SIDE VIEW
CLUTCH PACKS
BANDS
A band is a steel strap with friction material bonded to the inside surface.
One end of the band is anchored against the transmission case while the other end is connected to a servo.
TORQUE CONVERTER
HYDRAULIC SYSTEM
The Hydraulic system is a complex maze of passages and tubes that sends transmission fluid under pressure to all parts of the transmission and torque converter
It works with some components.
Oil Pump
Valve Body
COMPUTER CONTROLS
The computer uses sensors on the engine and transmission to detect such things as throttle position, vehicle speed, engine speed, engine load, brake pedal position, etc. to control exact shift points as well as how soft or firm the shift should be. Once the computer receives this information, it then sends signals to a solenoid pack inside the transmission
NON-COMPUTERIZED TRANSMISSIONS
Governor
Vacuum Modulator
Throttle Cable
Seals and Gaskets
SPOTTING PROBLEMS BEFORE THEY GET WORSE
Watch for leaks or stains under the car.
Check fluid for color and odor.
Be sensitive to new noises, vibrations and shift behavior.
TRANSMISSION REPAIRS
Adjustments and In-Car Repairs
Reseal job
Replace accessible parts
Complete Overhaul
Replacement unit vs. overhaul existing unit
Conclusion
Being able to drive a stick-shift means more than just understanding your gears, however. That's because to shift gears, you usually don't just move the shift lever and be done with it. (You can do this sometimes, but it's not recommended in day-to-day driving, and we'll get to it later.) Instead, you have to press the clutch pedal while you shift. . Keeping the transmission and its fluid cool, and in the correct operating-temperature range is crucial for long life.