Mechanisms - description v3
- 1. MECHANISMS They are part of machines and generally translate one kind of movement into another • They make a job easier to do. • They involve a kind of force. • They involve some form of motion.
- 2. Types of motion Linear: • movement in a straight line. Rotary: • movement in a circular direction. Reciprocating: • movement upwards and downwards in a straight line. Oscillating: • backwards and forwards motion along an arc. Make a simple drawing of each of them Give an example of each of them in objects around us Translate them into Spanish
- 3. TRANSMISSION MECHANISMS They cause the transmission of rotation from one axle to another axle The axle that produces the motion is called driver axle and the one that receives the motion, driven axle.
- 5. GEARS When the first axle (the driver axle) rotates, the motion is transmitted to the second or driven axle. It transmits rotation from one gear to another close gear. The two gears rotate in opposite directions.
- 6. WORM GEAR It allows transmission between two perpendicular axles. Worm gear : The driver axle is always coupled to it. Regular gear : The worm axle transmits rotation to it. It reduces the speed of the worm gear many times
- 7. BEVEL GEARS The mechanism transmits rotation between perpendicular shafts The gears have a cone- shape
- 8. SIMPLE GEAR TRAIN Three or more single gears forming a chain of gears. With three gears, driver and driven axles rotate in the same direction.
- 9. COMPOUND GEAR TRAIN Two or more single gears are coupled to the same axle. This mechanism works as large multiplier or reducer of the speed.
- 10. BELT DRIVE (pulleys system) It is made up of two grooved wheels linked by means of a tense belt. If the pulley wheels are different sizes, the smaller one will spin faster than the large one.
- 11. COMPOUND BELT DRIVE Several pulleys are coupled in the same axle This mechanism works as large multiplier or reducer of the speed
- 12. FRICTION DRIVE It is made up of two wheels in contact. The two wheels rotate in opposite directions.
- 13. CHAIN DRIVE It is made up of a chain that links the two toothed wheels. Both wheels rotate in the same direction. In some machines, the small wheel is called pinion, and the big one plate.
- 14. TRANSFORM MECHANISMS They cause the conversion from linear movements to rotations or vice versa.
- 15. CRANK and SLIDER crank and slider mechanism video It transforms the rotation of a crank into a linear, back-and- forth motion of a piston.
- 16. NUT AND BOLT When a bolt is turning, its rotation generates a linear, forward motion. This motion approaches or separates the bolt from a nut. In other situations the nut, instead of the bolt, moves.
- 17. CAM AND FOLLOWER Cam and follower mechanism When the cam rotates, it makes the follower to go up and down.
- 18. RACK AND PINION It transforms the rotation of a small gear (pinion) to a forward motion of a toothed belt or a rack (or vice versa). Rack and pinion video