mechanism

Plus de détails

Anatomical Terminology

par Jennifer Tripp

The importance of moving with young children in early childhood settings.

par Chloe Heslington

MODELS TEORICS D'APRENENTATGE MOTOR

par Esteve Mendez Escayola

glossary of biomechanics

par Nidia Constanza Velasquez Perez

mechanism

movement

distance can be changed by using pantograft mechanism

direction can be changed by using bevel gears

cranks,racket,springs

cables

usually made of serverals strands of steel wire

work well in tension

screw

used to convert rotary motion to linear motion

springs

type of springs

flat spring

return to its original shape when bent

material

usually metal

torsion spring

used to resist a turning force

tension springs

compression springs

ratchet and pawl

allow movement in one direction but not the other

rack and pinion

is used in

bench drill

CD rom drive

microscope

car steering wheel

cranks

are often used with a slider for converting movement from circular motion,or the other way round

is an arm that has one end connected to a shaft

basic type of motion

reciprocating

linear

oscillating

circular

levers

velocity ratio of movement

V.R=input movement/output movement

show relationship between input and output force

if the driver pulley is bigger than the driven pulley,the driven pulley turns faster than the driver.

four bar linkage is used for converting motion

one axis to another

one size to another

one speed to another

one type to another

turning point of a lever is called as the fulcrum

classes

class 3

class 2

class 1

change direction of movement

increase movement

fasterner

includes

nuts and bolts

a second nut or split pin can be used

nut

can come loose due to cibration

split pins

cap screw

used to hold machine parts together,one of the parts must be threaded to act as a nut

set screws

used to lock collars and wheel in position on a shaft

cam and gears

gear

used in

bicycle

hand drills

worm gaer

one complete turn of worm gear cause the worm wheel to turn by a single tooth

reduce speed but increase turning force

used to turn a worm wheel

bevel gear

used to transmit motion through 90degree

idler gear is required for the driver gear and the driven gear to be in the same direction

the smaller gear rotates faster than the bigger gear

spur gear

mesh and rotate in opposite direction

can be combined for

changing the direction of motion

increase turning force

controlling speed

is a wheel with teeth around its edge

converts circular movement to a kind of oscillatory motion.it cant work the another way around

common types

ecentric shape

snail

pear

specially designed and shaped pierce of material that rotates casing a lever or rod to move

defination

mechanical sytem

has input,process and output

used to change one kind of movement to another

move and control things

mechanical advantage

if MA is larger than 1,output is bigger than input force

MA=output/input

the ratio between output and input force