Transcript Lesson Objectives - Boxford Holdings

Lesson Objectives
Introduction To :Types Of Motion
Linkages
Types Of Motion
Linear Motion
Rotary Motion
Reciprocating Motion
Oscillating Motion
Linkages
• What is a linkage ?
• How are they used ?
Before Starting With Linkage
Kits
REVERSE MOTION LINKAGE:
As the top rod moves
to the left the bottom
rod moves to the right.
The bars move in
opposite directions.
Another way of
describing this linkage
is the direction of
movement in one rod
is reversed in the
other rod. The fixed
pivot is the centre of
rotation.
Walking Mechanism
PARALLEL MOTION LINKAGE:
As the large rod at the
top of the diagram
moves to the left the
two small rods at the
bottom move to the
right. All the rods are
parallel to each other.
PARALLEL MOTION LINKAGE:
TOOL BOX DRAWS:
When the lid of the
tool box is opened an
extra set of draws can
be 'unfolded'. This
allows more tools to
be stored.
PARALLEL MOTION LINKAGE:
In 1784 Watt found a
solution to his engine
problems (which he
called "parallel
motion") that was
developed in several
different
configurations.
CRANK AND SLIDER LINKAGE:
The rods move
forwards and
backwards in slider.
The fixed pivot anchor
the linkages to one
place.
CRANK AND SLIDER LINKAGE:
The crank which is the
rotating disc, the slider which
slides inside the tube and the
connecting rod which joins
the parts together. As the
slider moves to the right the
connecting rod pushes the
wheel round for the first 180
degrees of wheel rotation.
When the slider begins to
move back into the tube, the
connecting rod pulls the
wheel round to complete the
rotation.
BELL CRANK LINKAGE:
This linkage allows
horizontal movement
to be converted to
vertical movement. It
also works the
opposite way round. A
practical example of
this is the brake
mechanism on a
bicycle.
BELL CRANK LINKAGE:
BICYCLE BRAKES: Look at
the diagram carefully. As the
brake lever on the bike is
pulled the cable moves
upwards and forces the brake
blocks against the rim of the
wheel. Explain the type of
linkage involved - using notes
and diagrams. Look at the
page 'linkages' to help you
decide.
BELL CRANK LINKAGE:
From the SafeAir1 glider
wing pushrod on the
aileron.
Clear use of a bell crank
Windscreen Wipers
Design a linkage to solve this problem –
You cannot cross the wall
One Answer
Free Linkage Software
http://www.eductr.pref.kanagawa.jp/Link
Web/index_e.htm