Applimotion motors and actuators utilize rotary and linear brushless motor technology to create unique motion solutions. While brushless motors have been around for a very long time, the detailed application of this technology has countless variants. Our team of engineers work closely with the customers to understand their application and create an optimized solution. We provide frameless motor kits, to support the maximum level of integration into customer’s machines, as well as fully integrated sub-system solutions. The Applimotion direct drive motors and stages are the product of unparalleled application expertise and performance-driven design.
Frameless Motor Kits
Frameless motor kits are motor assemblies that do not include housings and only include a stator and rotor. A back iron can be included, which completes the magnetic circuit of the motor kit. The stator and rotor can be embedded directly into custom mechanisms, allowing for greater flexibility and direct connection to the inertia load.
Fewer components are needed for frameless motor kits, compared to traditional housed motors, reducing the need for maintenance while increasing reliability, resulting in lower downtime and repair cost.
Permanent Magnet Synchronous Machines (PMSM)
In PMSM, current flowing through the windings of the stator is synchronized, creating a magnetic field that interacts with the permanent magnets in the rotor. This works to create torque for the rotor to move in rotation.
Permanent magnet synchronous machine is the correct term to describe both blushless DC (BLDC) and brushless AC motors (BLAC).
BLDC motors are by definition associated with a trapezoidal back emf waveform, and are driven with six state trapezoidal drives or sine drives. This motor and drive pairing creates torque ripple, and was the motivation behind the evolution to the BLAC motor.
BLAC motors mean their back emf waveforms are sinusoidal – commonly paired with a sine drive to create a ripple-free torque output. Either motor type can be paired with either drive type, but only the BLAC with the sine drive creates a ripple-free torque profile. Applimotion direct drive frameless motors are BLAC.
Slotted Stators (Motors)
Slotted stators have iron teeth with stacked laminations. These laminations are thin sheets of iron stacked on top of each other, designed to help reduce Eddy Currents throughout the iron core, reducing core power losses. An effect of the iron teeth can be cogging torque. Copper windings are wound around the teeth of the stator. Each tooth has a magnetic field and an inherent attraction to a single pole of the rotor. At low speeds, cogging torque can be more apparent than at high speeds due to the inertia of the system “masking” the deviation of opposing or helping cogging torque.
Slotless Stators (Motors)
Slotless stators have no teeth in the lamination stack, thereby eliminating the tooth to magnet attraction that causes cogging. In order for the windings to have structure, they are encapsulated in a potting material or epoxy resin. The lack of iron in the windings means slotless motors generally, but not always, have less power density. However, they benefit from having speed dependent loss, ideal for ultra-smooth, ultra-fast applications. Slotless technology is affective with direct drive precision systems because all torque is a function of phase current, and there are no unwanted or uncontrolled torque disturbances in slotless motors.
Direct Drive Frameless Motors