The document discusses the history and components of power steering systems in automobiles. It describes how hydro-mechanical power steering first appeared on agricultural tractors in the 1950s. The general circuit includes an oil reservoir, hydraulic lines, filters, and a pump that is driven by the engine. There are four main types of hydro-mechanical power steering systems that vary in how the control valve and actuator are mounted. The future of steering may involve "steer-by-wire" or "drive-by-wire" electronic systems that eliminate the mechanical connection. Power steering provides advantages like reducing driver fatigue but also has disadvantages like increased complexity and cost.

1. Power Steering System In Automobiles Presented by Vishal V. Chitare (1DB07ME425)‏ [email_address] Don Bosco Institute of Tecnology. Bangalore.

2. Introduction. History. General Circuit . Component In Power Steering. Types of HMPS. Future of Power Steering. Advantages and Disadvantages. Conclusion. Power Steering

3. Introduction Steering is the term applied to the collection of components, linkages, etc. which allow for a car or other vehicle to follow a course determined by its driver.

5. History of Hydro-mechanical Power Steering (HMPS)‏ Hydro-mechanical power steering was the first type to be used on agricultural tractors in the early 1950’s. Suitable for small to medium tractors where power steering can be an option to manual steering. Once the size of the tractor becomes too big for manual steering, hydro-mechanical steering is usually not cost effective.

6. General Circuit Oil Reservoir Must be large enough to hold more than all of the oil for the system. Should be capable of dissipating heat in oil. Hydraulic Lines Flexible hoses due to the steering components movements.

7. General Circuit Filters Oil Filter Preferably installed in the return line. A 10-micron or smaller filter is recommended. Air Breather Filter The “breather” or vent in the reservoir. A 3-micron filter is recommended.

8. Components in Power Steering Pump Steering gears Rotary valve Linkages

9. Components in Power Steering Power Steering Pump Usually a vane-type pump or similar. Driven by the engine. Power Cylinder Double-acting differential cylinder. Steering response to left and right turns is slightly different. Hardly noticeable.

10. HMPS Type 1 The integral valve and actuator coupled to steering linkage. Easiest to adapt to an existing mechanical steering layout. Only two hoses are neede

11. HMPS Type 2 Steering column mounted control valve with separate, remote actuator coupled to a linkage member. Creates a highly congested area with all of the hoses. Four Hoses are needed: supply, return and a pair to the actuator. Creates noise, heat and vibration

12. HMPS Type 3 Control Valve and actuator separately mounted in the steering linkage. Keeps the area around the steering wheel from becoming too congested. Four hoses are required.

13. HMPS Type 4 The control valve and the actuator are mounted on the steering column, the actuator drives the pitman arm by rack and pinion or by crank arm means. Most sophisticated design Requires little or no steering linkage modification. Requires larger space envelope than other types.

14. Vane Type of Pump

15. ROTARY VALVE

16. Split Gears It converts the rotational motion of the steering wheel into the linear motion needed to turn the wheels. It provides a gear reduction, making it easier to turn the wheels.

17. Steering Gear Box Steering gears are enclosed in a casing known as steering gear box ( as shown in Fig.)‏

18. Recirculating-ball Steering The first part is a block of metal with a threaded hole in it. Works similar to a bolt that sticks into the hole in the block. These are used in havy duty comurcial vehicles. `

19. Power Rack-and-pinion

20. The Future of Steering - Drive by Wire As the majority of today’s hydraulic power steering systems are designed to have the steering pump running constantly, pumping fluid around the system, it wastes valuable horsepower, which translates into wasted efficiency and therefore fuel. One concept is the "steer-by-wire" or "drive-by-wire" system. These system would completely eliminate the mechanical connection between the steering wheel and the steering, replacing it with a purely electronic control system.

21. Advantages Preventing the wheels from transferring the load to the steering column Reducing the driver’s fatigue Low input torque and continuous steering function Oil output directly proportional to the steering speed

22. Disadvantages Design is compications and increased in cost. Fluid leakage.

23. Conclusion By studing all these we can conclude that the power stering is nesessory for the modern cars. Now a days we can see almost all cars having a power steering. It provides good handling to the driver, gives better comfert, and make him less fatigue.

24. Power Steering Thank you