Bokena Series pt 2 blog 2: ALAMAK 3D PRINTED GEARS

Hello everyone, welcome back to another bokena series by Dr Abhishek (Self - Proclaimed). Today I will be going through with y'all the concepts of gears. I'm sure most of you have seen a gear system or at least heard of it before. 

For those who have somehow forgotten what a gear looks like, here's a picture.

In this page, I will describe:

1. The definition of gear module, pitch circular diameter and the relationship between gear module, pitch circular diameter and number of teeth.

So what is a gear module? 

Gear Module (m)

- The size of the gear teeth (z); Typically measured in millimeter (mm)

The teeth of the gear are the jaggered metal bit allowing the gear to spin

Next I am going to talk about the pitch circular diameter

Pitch Circular Diameter (PCD)

- An imaginary circle that passes through the points of the 2 interlocking gears.

Below is a picture showing both what the Teeth of the gears look like and the Pitch diameter

So what is the point of me talking about pitch circular diameter and gear module ? 

Essentially, to find the Pitch Diameter we can use an equation using the gear module (m) and the number of teeth present on the gear (z)

PCD = m * z

2. The relationship between gear ratio (speed ratio) and output speed, between gear ratio and torque for a pair of gears.

Moving on to gear ratio, HUH gear also got ratio meh?

Gear ratio is just the ratio between the number of teeth the driven gear has over the number of teeth the driver gear has. (Output teeth to Input teeth)

No. driven gear teeth / No. driver gear teeth

So what is the driver gear and the driven gear ?

Driver gear - The gear that supplies energy to the allow the gears to spin

Driven Gear - The gear where the force is directed upon

Similarly, speed ratio is just the output speed of the gear over the input speed of the gear.

Output Speed / Input Speed

When it comes to a pair of gears, the lower the gear ratio the higher the output speed. Same for the vice versa, where the higher the gear ratio the lower the output speed. Showing the relationship between gear ratio and output speed is inverse.

3. How I can design a better hand-squeezed fan, including the sketches

A hand squeeze fan at this day and age, is very unnecessary especially with the usage of batteries but if it does come to the case where you are sweating profusely and need to use one. You would prefer a fan which required lesser effort to provide wind.

Please feel free to appreciate my groups lovely sketchy ( DON'T JUDGE I TELL YOU )

There were 2 main ideas we came up with to increase efficiency of the hand squeezed fan

- Addition of a spring

The spring will be used to crank up the fan, allowing the user to exert lesser effort when squeezing the fan and it will also allow the fan to function better

- Using smoother gear materials

By using smoother gear materials, we can ensure that the gears and turn with lesser frictions meaning that lesser force would be needed for the fan to function. Similar to the spring, when more force is used the amount of wind produced would also increase

4. How my practical team arranged the gears provided in the practical to raise the water bottle, consisting of:

1. Calculation of the gear ratio (speed ratio)

2. The photo of the actual gear layout.

1. Calculation of the number of revolutions required to rotate the crank handle.

2. The video of the turning of the gears to lift the water bottle.

5. My Learning reflection on the gears activities.

For the gears activity, I was not present due to medical reasons but I will still share what my groupmates had gone through with me during their practical.  OH MY right, worst timing to get a fever is just before your practical day. GEEGEE

Mainly they talked about the struggles of using a 3D printed gear to actually function. We all know the thoroughness of 3D printers when it comes to precision. The main part which I had helped out with were the calculations of the how turn would be required to get the bottle up. 

They had also discussed with me about how they had noticed that the theoretical number of turns required was lower compared to the actual number. And factors they had concluded was how the gears were not smooth causing for additional friction making the actual turn more than calculated. They also discussed about how they had to reposition the gears to make the turning more effective.

Next, they also discussed about how they had fun dismantling a hand squeezed fan, I mean as destructive person who would not want to break apart a fan. That's the part I felt like I missed out the most. 

However, looking at the practical that they did made me further realise how chemcial engineer is not just about chemistry and working in the industry together with equipment and whatsoever. It is more about adapting into different situations and looking at different point of views when it comes to thinking. I also showed me that studying chemical engineering is truly the start of being a UNIVERSAL ENGINEER.

Here is a cute picture of my groupmates after their practical\

And this is image of my buddy Jun Yi playing around with the dismantled hand squeezed fan.

Thank you for tuning into this week's blog. I apologize for the lack of content but fear not I will be there for the next practical as its the rise of Abhishek.