slide1 l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Forging new generations of engineers PowerPoint Presentation
Download Presentation
Forging new generations of engineers

Loading in 2 Seconds...

play fullscreen
1 / 23

Forging new generations of engineers - PowerPoint PPT Presentation


  • 91 Views
  • Uploaded on

Forging new generations of engineers. Lever and Linkage Systems. Methods of Power Transmission. The 3 Classes of Levers. Each class has the fulcrum, effort and load arranged in a different way. The three classes are:. Class 1 Lever. Fulcrum between the load and the effort. Class 2 Lever.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Forging new generations of engineers' - alvis


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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
lever and linkage systems
Lever and Linkage Systems

Methods of Power Transmission

the 3 classes of levers
The 3 Classes of Levers
  • Each class has the fulcrum, effort and load arranged in a different way.
  • The three classes are:
class 1 lever
Class 1 Lever
  • Fulcrum between the load and the effort
class 2 lever
Class 2 Lever
  • Load between the fulcrum and the effort
class 3 lever
Class 3 Lever
  • Effort is between load and fulcrum
rocker arm
ROCKER ARM
  • Has an input and output arm which rock around a fulcrum point
  • Acts as a link which transmit force or motion between moving parts
  • Operate usually as a first class lever
  • Change linear input motion to an opposed linear motion
bell crank
BELL CRANK
  • A bent first class lever that pivots at the bent point or elbow
  • Used to change the direction of force or motion 90 degrees or less
  • Used to convert rotary motion to straight line or reciprocating motion
bell crank9
BELL CRANK
  • Reciprocating motion

Top

    • pin A moves slider to right
    • pin B moves bell crank which moves slider to left

Bottom

    • pins move crank; spring returns to start position
double bell crank
DOUBLE BELL CRANK
  • PUSH, PULL TYPE

PUSH

    • requires stiff connecting rods

PULL

    • can use flexible wires,cables, ropes
differential linkage
DIFFERENTIAL LINKAGE
  • Used to combine several motion inputs into a resulting output
  • Three pivot points, none of which are fixed but are free to float within limits
  • Any pivot can function as an input
  • A motion control mechanism rather than a means of transmitting force or power
four bar linkages

FOUR-BAR LINKAGES

(Whatever the motion, each point on a moving link must move in the same PLANE, and all the links must be parallel)

Types of four-bar linkages:

PARALLEL LINKAGE

SCISSOR LINKAGE

four bar linkages13
FOUR-BAR LINKAGES
  • To make a four-bar linkage a usable device, one of the four links, or one of the pivots, must be fixed
  • Depending on the fixed pivot or link different motion outputs will occur
four bar linkages14
FOUR-BAR LINKAGES
  • Fixed link
    • links pivoting from the ends of the fixed link are either input links or input and output links
    • the moving link opposite the fixed link is the connecting link
four bar linkages15
FOUR-BAR LINKAGES
  • FIXED PIVOT
    • the point opposite the the fixed point is normally the output point
    • the remaining two pivot points are usually the input points
parallel linkage
PARALLEL LINKAGE
  • To provide parallel motion of a line or a surface as the linkage moves about two controlled pivot points
  • The arms remain parallel through the operation of the connecting link

Eg: man lift, robot gripper

scissor linkage
SCISSOR LINKAGE
  • To change the direction of a linear motion input to a linear motion output that is perpendicular to the input
  • Large motion output (distance advantage) with a small motion input
  • Especially true of a series of connecting linkages
  • One fixed pivot point
scissor linkage18
SCISSOR LINKAGE
  • Two pair of links of different length
    • Less force at input pivot point - close to pivot point
    • output is identical
scissor linkage19
SCISSOR LINKAGE
  • Two pair of links of different length
    • More force at input pivot point - farther from pivot point
    • output is identical
watt straight line motion
WATT STRAIGHT LINE MOTION
  • Does not form a parallelogram but consists of two equal length pivoting links and a connecting link
  • Produces a straight line motion in the connecting link
toggle linkage

TOGGLE LINKAGE

Latching

Non-latching

toggle linkage22
TOGGLE LINKAGE
  • LATCHING
    • capable of snap action from one state to an alternate state
    • arm length may be different
    • may have a toggle stop to produce latched condition
toggle linkage23
TOGGLE LINKAGE
  • NON-LATCHING
    • operated so that the two toggle arms never quite straighten
    • may have a toggle stop to produce latched condition

e.g.

rock crushers

hay balers