Thabo is 'n masjienopERATOR en het opdrag gekry om 'n reguitrat met 'n steelskirkeldiameter van 136 mm en 'n module van 4 te sny - NSC Mechanical Technology Fitting and Machining - Question 6 - 2021 - Paper 1

The dedendum (d) is calculated as:

$d = 1.157 \times m$

Substituting the module value:

$d = 1.157 \times 4 = 4.63 \text{ mm}$

The outside diameter (OD) is determined using:

$OD = PCD + 2 \times d$

Substituting the values:

$OD = 136 + 2 \times 4.63 = 144 \text{ mm}$

The circular pitch (CP) is calculated by:

$CP = m \times \pi$

Substituting the module:

$CP = 4 \times \pi \approx 12.57 \text{ mm}$

To calculate the minimum width of the dove tail (w), the formula is:

$w = 190 - 2 \times (DE)$

First, calculate DE using the triangle properties:

$DE = \frac{AD}{tan(60^\circ)}$

Where:

$AD = 38, DE \approx 21.94 \text{ mm}$

Thus:

$w = 190 - 2 \times 21.94 = 146.12 \text{ mm}$

The distance over the rollers (M) can be calculated as:

$M = w + 2(AC) + 2(R)$

First, find AC using:

$AC = BC \times tan(30^\circ)$

After calculations:

$M = 146.12 + 2 \times (25.98) + 15 \approx 228.08 \text{ mm}$

Using the formula for indexing:

$Indexing = \frac{40}{n}$

For 163 teeth:

$n = \frac{(160 - 163)}{40} = -0.075, \text{ which indicates no full turns available.}$

The change gears can be calculated using:

$D_{BR} = (A - n) \times 40$

And solving for each required variable accordingly based on the previous steps.