Slotted link mechanism Lab Manual Engineering Dynamics

EXPERIMENT NO 4

OBJECTIVE:

To perform slotted link mechanism

Apparatus:

Crank, Slider, Connecting Rod, Slotted Link

PROCEDURE:

1.   Set all the equipment for the experiment of slotted link mechanism.

2.   Adjust the angle of the circle of the crank at zero degree.

3.   Twist the angle of the circle 20” and measure linear position of the slider.

4.   Repeat the above process by increasing 20” of the angle of circle until the angle reaches 360” and each time measure the resulting distance of the slider.

5.   Plot a graph between linear position of slider on y-axis and the angle of circle on x-axis.

Theory:

A slotted link mechanism  is a reciprocating motion mechanism, converting the linear motion of a slider into rotational motion, or vice versa. The piston or other reciprocating part is directly coupled to a sliding yoke with a slot that engages a pin on the rotating part. The location of the piston versus time is a sine wave of constant amplitude, and constant frequency given a constant rotational speed.

Slotted link:

An oscillating and rotating  link of a crank mechanism which is provided by a slide way. 

Slotted link mechanism:

                             A device used in reciprocating machine to make the return stroke faster than the power stroke.

Simple Harmonic Motion:  

                  Simple harmonic motion is defined as when a mass or point moves in such a way that its acceleration is proportional to its displacement from a fixed point in its path and is directed to the point, the motion is said to be simple harmonic.

Sr. No	Angle	Linear Position 1	Linear Position 2
1
2
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19

  

Graph:

               

Precautions:

Ø  All the apparatus should be in a good condition and work properly.

Ø  Each time, the increased angle of the circle should be of exact 20”.

Ø  Read the linear scale readings carefully.

Application:

Shaper Machine

The shaper machine is used to machine flat surfaces especially where a large amount of metal has to be removed.

In a shaper machine cutting action takes place while the cutting tool moves in the forward direction .It does not take cut in backward direction. This is an idle stroke and time required for this stroke is idle time. To reduce idle time, crank and slotted link mechanism used.

Piston water pump, with a scotch yoke connection to its flywheel

This setup is most commonly used in control valve actuators in high-pressure oil and gas pipelines.

Although not a common metalworking machine nowadays, crude shapers can use Scotch yokes. Almost all those use a Whitworth linkage, which gives a slow speed forward cutting stroke and a faster return.

It has been used in various internal combustion engines, such as the Bourke engine, SyTech engine, and many hot air engines and steam engines.

The term scotch yoke continues to be used when the slot in the yoke is shorter than the diameter of the circle made by the crank pin. For example, the side rods of a locomotive may have scotch yokes to permit vertical motion of intermediate driving axles

Conclusion:

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