From Motors and Drives
Linear motor systems operate basically the same as rotating motors. The difference, of course, is that linear motion is produced, rather than clockwise or counterclockwise motion.
There are two main components of the linear stepper motor-the platenand the slider (sometimes referred to as the forcer). The platen could be considered the stator of the motor. The slider could be considered a linear rotor. Figure 3-47 indicates a linear stepper motor.
The electromagnetic "teeth" extend over the entire length of the platen. The slider also contains "teeth" and has both permanent magnets and coils that are electrically charged. It should be noted that the platen and slider have tooth structures that almost match. The slight offset is what causes the slider to be attracted to the next available magnetic field in the platen. The slider, in many cases, will contain air bearings that assist in developing a slight air gap. This air gap is where the magnetic flux is developed, and would be considered common to any standard AC induction motor.
When the slider coils are energized, the linear stepper motor moves in 1/4 tooth steps. Extremely fine resolution can be obtained from this type of motor, in some cases up to 25,000 steps per inch. This type of motor is well suited for applications where fast acceleration and high-speed movements are required, but where low mass or weight is needed.
Speeds of up to 100 ips (inches per second) are possible, with movements in increments down to 0.00005 inches. The linear stepper motor system has its advantages in precision open-loop control, mechanical simplicity, reliability, applications where space is limited, and the ability for multiple motion (more than one slider can be applied onto one platen). In addition, this type of system is an alternative in applications where leadscrews (with backlash issues), belts, pulleys, and gears are not practical.
Products & Services
Topics of Interest
AC and DC motors are the two major types in use today that are related to the industrial and HVAC applications. These motors provide the speed, torque, and horsepower necessary to operate the...
First, a certified lifting device has to be designed to current regulations and standards. It's the law in Ontario. When a lifter is certified you can be assured of the product's performance and that...
Tilter/Up-Ender meets customer challenge. Large, heavy, custom wood cabinetry must be manually lifted, wrapped, and placed on a conveyor belt prior to shipping. This process originally required at...
Frank van Hoorn 52.1 DESCRIPTION 52.1.1 General Heavy-lift transport ships form a particular sector of the dry cargo ships. These specialized ships are capable of transporting heavy and awkward...
The basic information necessary to select an appropriate tilter for an application.