Smoothness and lack of ripple are essential for the printing of elaborate color images on reusable plastic cups available at fast-food chains. The color image is made up of millions of tiny ink dots of many colours and shades. The entire cup is printed in one pass (unlike regular color separation where each color is usually printed separately). The gearheads must function smoothly enough to synchronize ink blankets, printing plates, and glass rollers without presenting any ripple or inaccuracies that may smudge the image. In this case, the hybrid gearhead decreases motor shaft runout error, which reduces roughness.
At times a motor’s capability may be limited to the stage where it requires gearing. As servo manufacturers develop more powerful motors that can muscle applications through more difficult moves and generate higher torques and speeds, these motors need gearheads add up to the task.

Interestingly, only about a third of the movement control systems operating use gearing at all. There are, of program, reasons to do so. Using a gearhead with a servo engine or using a gearmotor can enable the use of a smaller motor, thereby reducing the machine size and price. There are three main advantages of choosing gears, each of which can enable the use of smaller sized motors and drives and for that reason lower total system price:

Torque multiplication. The gears and quantity of the teeth on each gear produce a ratio. If a electric motor can generate 100 in-lbs of torque, and a 5:1 ratio gear head is mounted on its output, the resulting torque will end up being near to 500 in-lbs.
Whenever a motor is working at 1,000 rpm and a 5:1 ratio gearhead is mounted on it, the swiftness at the output will be 200 rpm. This speed decrease can improve system efficiency because many motors do not operate effectively at very low rpm. For example, look at a stone-grinding mechanism that will require the motor to perform at 15 rpm. This slow swiftness makes turning the grinding wheel difficult because the motor will cog. The variable resistance of the stone being ground also hinders its simple turning. By adding a 100:1 gearhead and letting the electric motor run at 1,500 rpm, the electric motor and gear head provides smooth rotation while the gearhead output offers a more constant drive using its output rotating at 15 rpm.
Inertia matching. Servo motors generate more torque relative to frame size because of lightweight materials, dense copper windings, and high-energy magnets. The effect is better inertial mismatches between servo motors and the loads they want to control. The usage of a gearhead to raised match the inertia of the electric motor to the inertia of the load can enable the use of a smaller electric motor and outcomes in a more responsive system that is easier to tune.

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