GEARS

Hi guys!!! Welcome to my 2nd blog!! You guys would have been probably waiting for my next blog. Since it is already 2 weeks, here I am with another blog😆😆!! This time,it is double the fun and excitement as we indulged in 2 activities this time. I have a lot to tell, so sit back and enjoy reading my blog!!!😁😁😁😁

During practical, my group members and I indulged in 2 activities involving gears. Well, what is this gears??? Yeah, I kinda know that some of you guys might not be familiar with gears. Hence, I will explain more about gears.

These are the definition of gear module, pitch circular diameter and the relationship between gear module, pitch circular diameter and number of teeth

Gear modules refers to the size of the gear teeth. The unit for module is mm. The larger a module number, the larger is the size of the teeth. Gears that mesh together are having the same module.

Pitch Circular Diameter (PCD) is the imaginary circle that passes through the contact point between two meshing gears. It represents the diameters of two friction rollers in contact and moves at the same linear velocity.

metric module (tooth size) = Pitch Circular Diameter/ number of teeth

m = PCD/Z

Below is the relationship between gear ratio (speed ratio) and output speed for a pair of gears

Gear ratio is inversely proportional to output speed for a pair of gears

Output speed = k/ gear ratio , where k is a constant

Gear ratio = (number of teeth of follower gear/number of teeth of driver gear)

As the gear ratio increases, the output speed of the gear decreases

As the gear ratio decreases, the output speed of the gear increases

Below is the relationship between gear ratio and torque for a pair of gears

Gear ratio is directly proportional to torque for a pair of gears

Torque = k . gear ratio , where k is a constant

Gear ratio = (number of teeth of follower gear/number of teeth of driver gear)

As the gear ratio increases, the torque of the gear increases

As the gear ratio decreases, the torque of the gear decreases

Below are the proposal design to make the hand-squeezed fan better

The number of rotations made by the fan should increase for the fan to provide more wind. This means that for output speed to increase, the gear ratio should be the lowest. For this to occur, the gear with the largest Pitch Circular Diameter must be connected to the handle of the fan, while the gear with the smallest Pitch Circular Diameter must be connected to the fan rotator.

Below are the description on how my practical team arranged the gears provided in the practical to raise the water bottle

Calculations of the gear ratio (speed ratio)

The photo of the actual gear layout

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

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

Below is my Learning Reflection on the gears activities

Before attending this practical, I had slight confidence on conducting the practical without any errors, as watching the videos in the pre practical only helped us improve our knowledge on gears. Moreover, I had only learned and conducted experiments about gears in secondary school, and it was a long gap from secondary school to year 2 of chemical engineering. Hence, I was not really confident in conducting the practical. We had to arrange the gears on the ABS board. Since many of the gears were compounded, we had to make a lot of changes to our arrangement, as our initial plan was to arrange from the smallest gear to the biggest gear, from the left to the right. We continuously kept changing our arrangement as there were a lot of variations, and we had to make sure that we actually had enough torque to lift the bottle. This taught me how to also make decisions instantaneously at the moment, as there was limited time provided to us , and we had to stick to one arrangement quickly. Although there was a probability of the arrangement failing, we had to trust our knowledge and the process and carry on with the activity. Not carrying out the practical due to disagreement of ideas would lead to the incompletion of the activity. This taught me to enhance my decision-making skills. In the future, I would facing situations like this when I will have to make quick decisions and not sit-on-the-fence, as the failure to make a decision on the spot could be extremely dangerous. Moreover, we had faced another problem. Some of the screws that we had put into the ABS board to hold the gears were not strong enough to hold the gears, especially when the ABS board was placed vertically. Therefore we had to continuously change our screws that were holding on to the gear and the ABS board. Some of the time, we had not tightened the screws properly to the ABS board, as we had wanted to move on to the next activity, causing some of the gears to drop on the floor during the test run. This caused us extra time as we had to put the gears back into the ABS board, and find the appropriate screw to be attached to the gears and the ABS board .This had taught me that I should have further checked the stability of the gears before the activity and should not have rushed to conduct the activity. In the future, I will face similar situations like this in the plant when I will have to do multiple things at the same time, and I cannot do the work haphazardly for the sake of finishing it, as this might result in serious consequences. For the second activity, we were able to fit all the gears in the fan. However, getting the fan to rotate was extremely difficult as I was scared that I would break the thin parts of the fan. However, after getting used to the fan, I overcame my fear and learnt to be confident on myself. In the industry, I will have to be confident in my actions if I know the procedure and I cannot be wasting my time hesitating to do it, due to fear of failure. I had learnt that one should not be afraid of failure as failure is the first step to success. I will have to learn to be more confident on myself.