The Principle of Gear Reduction - Essay Example

Gears are toothed machine parts including wheels and cylinders that mesh with each other to transmit power and change the speed or direction of motion. The gear teeth reduce slipping in gears to ensure synchronization of axles that are connected by the gears. The diameter and circumference are of less importance to the working of the gears provided their teeth mesh. Gear ratio refers to the ratio of the number of teeth in the driven gear to the number of teeth in the driving gear. The gear ratio is also defined by the length of the distance extending from the center of the gear to the point of contact with the other gear, in which case the gear ratio will be given by the ratios of the distances.  Gears are used to provide gear reduction in motorized machine parts and also make work easier.

The principle of gear reduction is applied whereby a small pinion, the driving gear, spins very fast to provide enough power to spin the wheel, the driven gear. The small pinion rotating fast will not provide enough torque. Torque is the force that tends to create motion. Torque is the product of force and distance covered. Motors designed to produce large torques are meant to operate at low speeds so as to increase their lifespan while producing the same amount of power as a motor operating at higher speeds and producing smaller torque. Power refers to the rate of doing work and its SI unit is the horsepower. This experiment studies how gear ratios can be used to determine torque.

Apparatus

The apparatus used was RE 140 motor, six gears, a small sprocket, a big sprocket, weights, a battery, and the 917D kit for the gear reduction. The battery provided power to the RE 140 motor at the range of 1.5V and 3V.

The experiment was conducted using a RE 140 motor and kit which included several combinations of gear reductions and masses of different weights. The gear reduction combinations included small sprocket and big sprocket which were combined as shown in the figure below.

The circuit diagram featured a simple control circuit with the 3-volt motor connected to the power source and a toggle control switch for determining the direction of the current. The current flow was to the left, and right, and no current flow. The connections to the right and left set of terminals were insulated to ensure that the wires do not short-circuit.

Methods and results

The voltage was supplied from a 3volt battery to the RE 140 motor which powered the 917 D gearbox. The gearbox provided six different gear ratios with the corresponding speed, revolutions per minute. The gears were tested with different weights to determine the weights they could take with the big and small sprockets. The results of the weights are shown below.