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Kollmorgen QT-4702-A
Model Series: QT Series (Frameless DC Torque Motors)
Product Introduction:
The QT-4702-A is a frameless brushless DC torque motor designed for direct-drive applications requiring high torque density and zero cogging torque. It integrates seamlessly into customer-supplied mechanical structures, eliminating the need for couplings, gearboxes, or bearings.
Detailed content
Technical Specifications:
| Parameter | Value |
|---|---|
| Outer Diameter | 47 mm (1.85 in) |
| Stack Length | 02 (Short Stack Configuration) |
| Continuous Torque | ~0.18 Nm (typical for QT-47 frame) |
| Peak Torque | ~0.54 Nm (typical for QT-47 frame) |
| Rated Voltage | 24 VDC (standard) |
| Winding Configuration | 3-Phase, 4-Pole |
| Torque Constant (Kt) | ~0.07 Nm/A (typical) |
| Terminal Resistance | ~4.5 Ω (typical) |
| Terminal Inductance | ~1.2 mH (typical) |
| Weight | ~45 g (motor only, no housing) |
| Operating Temperature Range | -20°C to +80°C |
| Insulation Class | Class H (180°C) |
| Commutation | Hall Sensor (3-Hall, 120° spacing) |
Structural Features:
- Frameless design: Stator and rotor supplied separately, no shaft, no bearings, no housing
- Slotless stator construction: Eliminates cogging torque entirely
- Rare-earth permanent magnets: NdFeB (Neodymium-Iron-Boron) on rotor
- Epoxy potting: Protects windings from environmental contamination
- Radial and axial magnetization options available
Functional Characteristics:
- Zero cogging torque for ultra-smooth motion
- High torque-to-inertia ratio
- Direct integration into rotary or linear stages
- Suitable for single-axis or multi-axis gimbal systems
Advantages:
- Eliminates mechanical backlash and compliance
- Reduces system component count
- Enables highest positioning accuracy in direct-drive configurations
- Compact form factor for space-constrained designs
Applicable Industries:
- Semiconductor wafer handling
- Medical imaging (CT, MRI gantries)
- Aerospace gimbal systems
- Optical beam steering
- Robotic joint actuators
Installation Requirements:
- Must be mounted into a precision-machined housing with customer-supplied bearings
- Stator outer diameter tolerance: ±0.025 mm
- Rotor must be concentrically aligned within ±0.01 mm
- Thermal path to housing required for continuous operation
Usage Notes:
- Do not operate without proper heat sinking at continuous torque
- Hall sensor wires must be routed away from high-current motor leads
- Maximum speed limited by back-EMF and drive voltage: typically ~5,000 RPM at 24V
