Engineering Science
Worksheets
SIMPLE MECHANISMS KIT
ES14
2. SCOTCH YOKE
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Date
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DB/1012
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ES14 Worksheet
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ES14 Worksheet
Scotch Yoke
Scotch Yoke
Aims
To investigate how the Scotch Yoke converts motion.
Experiment Setup
As shown in Figure 1, fix the mechanism to the Work Panel.
Figure 1 Experiment Setup
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Scotch Yoke
ES14 Worksheet
Experiment Procedure
1. Read the Guidance Notes (supplied).
2. Set the rotary position control to 0 degrees, so its arrow points to the 0.
3. Record the linear position (the number that its arrow points to).
4. Plot your results on the chart paper.
Rotary
Position
(angle in
degrees)
Linear
Position
(in mm)
Rotary
Position
(angle in
degrees)
0
190
10
200
20
210
30
220
40
230
50
240
60
250
70
260
80
270
90
280
100
290
110
300
120
310
130
320
140
330
150
340
160
350
170
360 (0)
180
Table 1 Blank Results Table
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Linear
Position
(in mm)
ES14 Worksheet
Scotch Yoke
40
Linear Position (mm)
30
20
10
0
0
20
40
60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360(0)
Rotary Position (degrees)
Figure 2 Blank Chart Paper
Questions and Conclusions
Describe the shape of the conversion curve. Is it sinusoidal and symmetrical as described in the Guidance
Notes?
Try and find more examples where a Scotch Yoke may be used.
If you have completed the ‘crank and slider’ experiment, then compare the two mechanisms and think
about the advantages and disadvantages of each type. Hint - think about the number of parts, smoothness
of motion and possible sources and types of friction.
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Notes
ES14 Worksheet
Notes
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