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 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.
The apparatus used were RE 140 motor, six gears, small sprocket, big sprocket, weights, 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 current. Current flow was to the left, 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.
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.