⚙️ เครื่องคิดเลขอัตราส่วนเกียร์

เกี่ยวกับเครื่องคิดเลขนี้

A gear ratio compares the teeth on the driven (output) gear to the driving (input) gear: ratio = driven / driving. It is the fundamental trade-off of gearing — a ratio above 1 is a reduction that turns the output slower but multiplies torque, while a ratio below 1 is an overdrive that spins faster but with less torque. Concretely, output RPM = input RPM ÷ ratio and output torque = input torque × ratio, so speed and torque always move in opposite directions (ignoring friction losses), keeping the power roughly constant.

As a worked example, a 10-tooth driving gear meshing with a 35-tooth driven gear gives a ratio of 35 / 10 = 3.5:1. Feed it 1,000 rpm and 20 N·m and the output turns at 1,000 / 3.5 ≈ 286 rpm but delivers 20 × 3.5 = 70 N·m. For a compound gear train, add a second pair under advanced options and the overall ratio is the product of the two stages — a 3:1 stage feeding a 2:1 stage gives 6:1 total. Enter a tyre diameter and final drive ratio and the tool also works out road speed from the wheel rpm.

Gear ratios are how machines match a power source to a load: low gears give a car or bicycle the torque to climb and accelerate, high gears give efficient cruising, and reduction gearboxes let small fast motors drive heavy slow loads. The same principle sizes winches, conveyors, clock mechanisms and drill speeds.