How The Different Gear Ratios Work

You can find gears in practically everything that has components that rotate. Automobile transmissions and engines typically come equipped with multiple gear ratios. When you crack open a video cassette recorder (VCR) and check on the inside, you will notice that it is jam-packed with gears. Clocks that are wound up manually or swing on a pendulum typically have multiple gears, particularly if they have bells or chimes. If the cover of the power metre that is located on the exterior of your home is transparent, you may be able to observe that it consists of ten to fifteen gears. Everywhere that there are engines or motors that generate rotational motion, there are gears present.In order for you to understand what each gear is doing, the next article will educate you on gear ratios as well as gear trains.

Putting The Wheels In Motion

The following are some of the most common applications for gears:

1. To make the rotation go in the opposite direction

2. To increase or decrease the speed of the spinning

3. To move a rotational motion to a different axis.

4. To make the rotation of two axes coincide with one another.

Having A Conceptual Understanding Of The Gear Ratio

It is not difficult to get a handle on the idea of gear ratios if you already have a good grasp of the concept of the circumference of a circle. Keep in mind that the circumference of a circle is calculated by multiplying the diameter of the circle by the value of Pi (which is equal to 3.14159...). As a direct result of this, the circumference of a circle or gear with a diameter of one inch is 3,14159 inches.

Let's say you have another circle, this time with a diameter of 0.635 inches (1.27 inches / 2), and you roll it in exactly the same way as seen below. Due to the fact that its diameter is only half that of the circle that was shown, it needs to do two full rotations in order to cover the same 4-inch distance. Because of this, a pair of gears, one of which is half the size of the other, will have a gear ratio of 2:1. When compared to the larger gear's single spin, the smaller gear's two revolutions are necessary to cover the same ground.Teeth are present on the majority of gears that exist in the real world. There are three advantages associated with having teeth:

1.They prevent the gears from grinding against one another. As a consequence of this, axles that are connected to one another via gears are always perfectly synchronised with one another.

2.They make it possible to determine the gear ratios with pinpoint accuracy. It is sufficient to only count and then divide the total number of teeth on both gears. Because of this, the gear ratio between these two gears is 3:1 because one gear has 60 teeth while the other gear only has 20.

3. They design it in such a way that it doesn't matter whether there are slight differences in the diameter and circumference of two gears. The number of teeth is what determines the gear ratio, thus it doesn't matter if the diameters are off by a small bit.

The Purpose Of Different Gear Ratios

The primary purpose of the gear ratio is to reduce the torque while simultaneously raising the speed, and vice versa. If you employ gear ratios that are higher than they need to be, your car will not move since initial acceleration requires more torque than horsepower. When driving on the highway, however, speed is more important than torque, thus having a lower gear ratio is not beneficial. This is because smaller gear ratios have a smaller gear range. As a result, the gear ratio might be considered a compromise between the vehicle's torque and its speed.

Different Types Of Gear Applications  

If you are looking to get a high gear ratio, the worm gear is the most effective choice for you to choose. In a worm gear, the teeth of the gear are brought into contact with a threaded shaft. When the shaft completes one spin, the gear advances one tooth. This occurs at regular intervals. In a very compact form, such as a windscreen wiper, a gear ratio of 40:1 indicates that the gear has a total of forty teeth in its configuration.Worm gears can also be found in a mechanical odometer, which is another common application for them.

More Torque Can Be Obtained By Using Larger Gears

Multiplying the circumferential force by the gear's radius yields the calculation for the torque, which is the measurement of the twisting force. Because of this, larger gears will have significantly more torque than smaller gears due to the larger radii of the larger gears.

An Explanation Of The Planetary Gear System

Gears have a wide variety of other applications.Planetary gear trains are a type of gear train that is more specialised than others. Planetary gears are the solution to the problem that is detailed further down. Let's say you need a gear ratio of 6 to 1, with both the input and the output turning in the same direction.

Planetary gearsets are fascinating for a number of other reasons, one of which is that they can generate different gear ratios depending on which gear is used as the input, which gear is used as the output, and which gear is allowed to remain stationary. For instance, we obtain a different gear ratio if the sun gear serves as the input, the output shaft is connected to the planet carrier, and the ring gear remains stationary during the process. In this particular illustration, for the planet carrier to complete one revolution while the planets are revolving around the sun gear, the sun gear must rotate seven times. This is due to the fact that the planet carrier completed one rotation around the sun gear while it was spinning in the same direction it was revolving in, hence explaining why this occurred. In this particular case, there is a drop that is proportional to 7:1.

You are free to rearrange everything once more, but this time you must ensure that the sun gear remains in its original position. Additionally, you must link the output of the planet carrier to the input of the ring gear. Because of this, the ratio of the gears would be reduced to 1.17:1. In an automated transmission, the various gear ratios are created using planetary gear sets. This is accomplished by employing clutches and brake bands to hold different portions of the gearset immobile and to change the inputs and outputs of the transmission.

The Workings Of Planetary Gears

Take the following example into consideration: You have two red gears that you need to keep in sync, but there is a distance between them. If you want both of them to turn in the same direction, you can do what is shown in the figure and put a huge gear in between them.

If you want the gears to rotate in opposite directions, another option is to utilise two gears of the same size.

In either case, the new gears are likely to have a significant weight, which means that axles will need to be fabricated to support them. When dealing with issues of this nature, it is common practise to resort to using a chain or a toothed belt as a solution.

Chains and belts have a number of advantages, including their low weight, the capacity to differentiate between two gears by a predetermined distance, and the ability to bind a large number of gears to a single chain or belt.

An engine for a vehicle may have a single-toothed belt that comes into contact with the crankshaft, two camshafts, and the alternator. If you had to use gears instead of the belt, it would be a significantly more challenging task.