| A linear induction motor is made up of an | | | | improved control, lower life cycle cost, |
| inductor which is made of individual cores | | | | reduced maintenance and higher performance |
| with a concentrated polyphase. Linear motors | | | | they are becoming the choice of the experts. |
| can be directly substituted for ball screw | | | | Linear motors are simple to control and easy |
| drives, hydraulic drives, pneumatic drives, | | | | to use. They have a fast response and high |
| or cam drives. | | | | acceleration. Their speed is not dependant on |
| | | | contact friction so it is easier to pick up |
| A linear induction motor is basically what is | | | | speed quickly. |
| referred to by experts as a "rotating | | | | |
| squirrel cage" induction motor. The | | | | Stepper motors are a special kind of motor |
| difference is that the motor is opened out | | | | that moves in discrete steps. When one set of |
| flat. Instead of producing rotary torque from | | | | windings is energized the motor moves a step |
| a cylindrical machine it produces linear | | | | in one direction and when another set of |
| force from a flat machine. The shape and the | | | | windings is energized the motor moves a step |
| way it produces motion is changed, however it | | | | in the other direction. The advantage of |
| is still the same as its cylindrical | | | | stepper motors that the position of the motor |
| counterpart. There are no moving parts, | | | | is "known". Zero position can be determined, |
| however and most experts don't like that. It | | | | if the original position is known. |
| does have a silent operation and reduced | | | | |
| maintenance as well as a compact size, which | | | | Stepping motors come in a wide range of |
| appeals many engineers. There is also a | | | | angular resolution and the coarsest motors |
| universal agreement that it has an ease of | | | | typically turn 90 degrees per step. High |
| control and installation. These are all | | | | resolution permanent magnet motors are only |
| important considerations when thinking about | | | | able to handle about 18 degrees less than |
| what type of device you want to create. The | | | | that. With the right controller stepper |
| linear induction motor thrusts ratio varies | | | | motors can be run in half-steps, which is |
| depending mainly on the size and rating. | | | | amazing. |
| Speeds of the linear induction motor vary | | | | |
| from zero to many meters per second. Speed | | | | The main complaint about the stepper motor is |
| can be controlled. Stopping, starting and | | | | that it usually draws more power than a |
| reversing are all easy. Linear induction | | | | standard DC motor and maneuvering is also |
| motors are improving constantly and with | | | | difficult. |