1 / 35

Prepared by: Tripti Bhaskaran Dept. of Electrical and Computer Engineering Utah State University

ECE5320 Mechatronics Assignment#01: Literature Survey on Sensors and Actuators Topic: HYDRAULIC BRAKE SYSTEM. Prepared by: Tripti Bhaskaran Dept. of Electrical and Computer Engineering Utah State University. 3/11/2005. REFERENCE LIST. http://www.tpub.com/fluid/ch1f.htm

masako
Télécharger la présentation

Prepared by: Tripti Bhaskaran Dept. of Electrical and Computer Engineering Utah State University

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ECE5320 MechatronicsAssignment#01: Literature Survey on Sensors and Actuators Topic: HYDRAULIC BRAKE SYSTEM Prepared by: Tripti Bhaskaran Dept. of Electrical and Computer Engineering Utah State University 3/11/2005

  2. REFERENCE LIST • http://www.tpub.com/fluid/ch1f.htm • http://www.brakecouncil.org/ • http://www.atiactuators.com/products.htm • http://maritime.org/fleetsub/hydr/chap1.htm • http://science.howstuffworks.com/hydraulic1.htm • http://fluid-power.globalspec.com ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  3. REFERENCE LIST • http://www.mico.com/literature/resource.php3 • http://www.machinetooldistributor.com/press-brakes.htm • http://www.easternmarine.com • http://www.innerauto.com/innerauto/anim/brake.html • http://www.e-z.net/~ts/hybrakes.htm • http://www.20v.org/brakprob.htm ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  4. EXPLORE FURTHER • The world of brakes in animation. A very interesting website showing the working of brakes. Click on the link below http://www.innerauto.com/main.html • Electro-Hydraulic brake system by Continental Automotive system. A computer monitors each braking maneuver and calculates the optimum hydraulic pressure for each wheel. • ABS – anti locking brake systems. The most popular form of Hydraulic brakes. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  5. EXPLORE FURTHER • Hydraulic Press Brakes used in heavy sheet metal work and Machine tool industry. Click on link below to see products http://www.multipress.com • The different types of Disc and Drum brake systems. • The use of Hydraulics in submarine engineering. Click on link below http://www.maritime.org/fleetsub ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  6. MAJOR APPLICATIONS • Construction Site Machinery: bulldozers, backholes, shovels, loaders, fork lifts and cranes. • Hydraulic brakes systems by different manufacturers are used in all types of cars in the market. • The ABS braking system is the most useful and safe kind of braking system. • Submarines, bikes, lifts, elevator use some form of Hydraulic Brakes. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  7. Applications ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  8. Introduction What is the meaning of hydraulics ? Tool or equipment powered by the movement of fluid under pressure. Hydraulics is defined in engineering textbooks as the engineering application of fluid mechanics. Hydraulics includes the study of the behavior of enclosed liquids under pressure, and the harnessing of the forces existing in fluids to do some practical task such as steering a submarine or applying brakes. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  9. Laws Governing Unconfined Liquids ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  10. Principle behind Hydraulics PASCAL’S LAW Pressure exerted at any point on a confined liquid is transmitted undiminished in all directions. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  11. Pascal’s Law In Hydraulics Multiplication of force ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  12. Hydraulic Brakes Multiple Piston System Allows force to be transmitted undiminished to more than one piston. Multiplication of forces takes place. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  13. Components of a Hydraulic Brake System ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  14. What are these elements ? • Brake Pedal • Master Cylinder Piston • Master Cylinder • Brake lines • Brake Cylinders (4 in number for each wheel) • Brake Pistons, two at each opposed to each other and pressing the brake shoes into the brake bands. • Brake bands press into the wheels causing friction and hence a slow down. • The friction action. • The springs which brings back the break shoes. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  15. Working • When the brake pedal is depressed, the pressure on the brake pedal moves the piston within the master cylinder, forcing the brake fluid from the master cylinder through the brake lines to the wheel cylinders. • The wheel cylinders contain two opposed output pistons, each of which is attached to a brake shoe fitted inside the brake drum. • Each output piston pushes the attached brake shoe against the wall of the brake drum, thus retarding the rotation of the wheel. • When pressure on the pedal is released, the springs on the brake shoes return the wheel cylinder pistons to their released positions. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  16. Working • This action forces the displaced brake fluid back through the flexible hose and tubing to the master cylinder. • The force applied to the brake pedal produces a proportional force on each of the output pistons, which in turn apply the brake shoes frictionally to the turning wheels to retard rotation ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  17. Brake Pedal Works on the principle of Leverage. The pedal is designed in such a way that it can multiply the force from your leg several times before any force is even transmitted to the brake fluid. Changing the pivot point we can get the desired multiplication of force and movement. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  18. Working of Master Cylinder • To increase safety, most modern car brake systems are broken into two circuits, with two wheels on each circuit. If a fluid leak occurs in one circuit, only two of the wheels will lose their brakes and your car will still be able to stop when you press the brake pedal. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  19. Two Circuit Master Cylinder ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  20. The Braking Mechanism Once the power from the brake pedal has been transferred to the brake cylinders the actual braking can be implemented in four ways. • Disc Brakes • Drum Brakes • Power Brakes • Anti Lock Brakes The first two have been explained in the next few slides. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  21. Disc Brake System • The disc brake have a caliper, which squeezes the brake pads against the wheel. • In a disc brake, the brake pads squeeze the rotor instead of the • Friction between the pads and the disc slows the disc down. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  22. Drum Brake System • The piston pushes the brake shoes against the drum and the friction causes the braking motion. • Apart from that it also has a adjustor and emergency brake system for safety and long life. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  23. ABS Brake Systems • The most important and safe types of Hydraulic brake systems is the Anti Locking Brake System. • Main advantages of ABS locking system are it helps in preventing skidding on slippery roads. • The driver will be able to stop faster and will be able to steer while stopping. • Four main components • Speed sensors, Pump, Valves, Controller. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  24. ABS Brake Components • Speed sensors can detect when the wheel is going to lock. • Valve in the brake line, open during normal opeartion, closed when driver pushes pedal too hard and releases pressure slowly. • Pump to build the pressure again. • Controller controls the valves with input from speed sensors. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  25. ABS at work • Controller looks for rapid decelerations in wheels which happens before lock up. • It controls valves to reduce pressure until it sees acceleration. • Results in tire slowing down at the same rate as car hence avoiding skidding. • Some ABS systems can cycle up to 15 times in a second. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  26. Brake Fluid Three main types of Brake fluids • DOT3 (glycol based, absorb water) • DOT4 (glycol based, absorb water) • DOT5 (silicon based, do not absorb water) The important characteristics of brake fluid is boiling point. If they have low boiling point will convert to gas leading to failure. DOT3 and DOT4 absorb water and this decrease boiling point. DOT5 does not but any water molecules inside can cause corrision. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  27. Disadvantages of Hydraulic Brakes Systems • Water in the brake system can cause very serious problems as the water can evaporate and the fluid becomes compressible. • Water causes rust and corrosion in the metal parts of the system and makes it difficult for the seals to operate correctly and produce the high pressures needed for braking. • The brake pads can wear out very easily if the brake is not manufactured properly. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  28. Disadvantages of Hydraulic Brakes Systems • Grabbing brakes are most often caused by contaminated linings. • Grease or oil can cause the linings to swell at spots and on drum brake systems these swollen spots contact the drum too quickly and can cause the brakes to grab. • Sometimes a brake squeal is an indication that the linings or pads are worn badly enough to allow metal to metal contact. Disk brakes can squeal if they are improperly installed. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  29. Straight Bore Master Cylinder ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  30. Fluid Reservoir ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  31. Slave Cylinder ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  32. Wheel Cylinder ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  33. Disc Brake ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  34. Manufacturer & where to Buy • MICO hydraulics and Brake system produces Master cylinder, slave cylinders, remote actuators and everything to make a hydraulic brake system. * Hydro Air LLCAddress: 243 State St North Haven, CT 06473Phone: 203-248-8863Fax: 203-248-8867 * Company: Fitzsimmons Hydraulics, Inc.Address: 4400 Shisler Road Clarence, NY 14031Phone: 716-759-8389 • Universal Brakes provides a comprehensive range of parts for all makes of vehicles. * California Warehouse 800 E. 230th Street Carson, CA 90745 • Ortlinhaus Sinus produces hydraulic brakes which have emergency release facility • Orttech 2425 Aurora Rd. Solon, OH 44139 2821 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

  35. Conclusion I hope this presentation has given you useful insights in the working and use of Hydraulic Brakes. Thank you ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

More Related