#Openscad gears series

Skewing the teeth like this around the circumference of the gear results in a helical pattern, hence the name helical gear. To counter this, teeth can be cut at an angle to the axis of rotation.

Also, because the entire width of the tooth surface meshes at once, spur gears tend to make a lot of noise at higher speeds as the teeth clack together. The axes of spur gears all have to be parallel to each other within the gear train, so there’s no way to transmit power to another rotational plane. Many low to medium speed gear trains use spur gears, which have a simple geometry that’s easy to mass produce. Helical involute gears, generated by ’s classic OpenSCAD code.The simplest gears, with teeth cut straight across the face of the circumference of a disk, are called spur gears. So, if the driving gear has a diameter of 1 cm and the driven gear is 10 cm across, the gear train will increase the torque 10-fold while reducing the rotational speed by a factor of 10.

#Openscad gears series

Multiple gears connected in series are called a gear train, and if the diameters of gears in the gear train are different, the torque transmitted will be proportional to the difference. The teeth are sized and shaped to mesh with teeth on other mechanical elements to transmit torque.

Within a few hundred years, precisely machined metal gears had enabled complex geared devices like the Antikythera mechanism to be built in Greece.Īt its simplest, a gear is nothing more than a wheel with some sort of teeth cut into its circumference. Human use of gears dates back at least to third-century BC China, and the technology spread rapidly and widely. The next installment of our series on Mechanisms will take a brief look at gears and their applications.Īs is often the case, evolution is the best inventor, and a geared mechanism linking the rear legs of juvenile planthopper insects predates the human invention of gears by a couple of billion years. From ancient water wheels and windmills that ground grain and pounded flax, to the drive trains that power machines of war from siege engines to main battle tanks, gears have been essential parts of almost every mechanical device ever built. Even before the Industrial Revolution, gears of one kind or another have been put to work both for and against us.