Performance Curves
Request torque-speed, efficiency, and temperature-rise data for the quoted winding and cooling condition.
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Frameless Torque Motors
Rotor and stator motor kits for direct-drive rotary axes, robot joints, gimbals, and precision OEM machinery.
Target Buyer:Best for OEM engineering teams replacing geared rotary drives with compact direct-drive torque control.
Capability Highlights
- Factory-side stator and rotor kit supply for compact mechanical integration.
- Custom winding, stack length, lead wire, and sensor interface support.
- Designed for high torque density, low cogging, and smooth servo control.
Typical Applications
- Collaborative robot joints and compact rotary actuators
- Optical gimbals, pan-tilt systems, and antenna pointing modules
- Semiconductor equipment, inspection stages, and precision indexing axes
Engineering Focus
- Air gap tolerance, rotor retention, and stator mounting method must be defined early.
- Thermal path through the customer housing drives continuous torque performance.
- Motor constants, winding selection, and servo drive limits should be matched together.
Key Evaluation Matrix
| Metric | Typical Range | Why It Matters |
|---|---|---|
| Continuous torque | 0.2-80 N·m by frame and cooling path | Defines sustained load capability after thermal limits are considered. |
| Peak torque | 2-4x continuous torque depending on duty cycle | Determines acceleration margin and transient disturbance handling. |
| Torque ripple | Application-dependent low-cogging design target | Critical for smooth robot motion, optical pointing, and inspection axes. |
Baseline Parametric Fields for RFQ Review
Final values depend on motor size, winding, thermal path, and custom scope. Include these fields in the first RFQ so engineering can return a usable model or custom design path.
| Parameter | Unit | RFQ Note |
|---|---|---|
| Rated voltage | VDC | Match bus voltage and servo drive current limit. |
| Continuous torque | N·m | State thermal condition and duty cycle. |
| Peak torque | N·m | Define duration and repetition rate. |
| Rated / maximum speed | rpm | Include control and mechanical limits. |
| Torque constant Kt | N·m/Arms | Used for drive sizing and current estimate. |
| Motor constant Km | N·m/√W | Supports efficiency and heat comparison. |
| Back EMF constant | V/krpm | Must match speed and voltage ceiling. |
| Resistance / inductance | Ω / mH | Needed for drive tuning and thermal model. |
| Rotor inertia | kg·cm² | Affects acceleration and control response. |
| Weight / insulation class | kg / class | Supports payload, heat, and safety review. |
| Torque ripple | % or N·m | Critical for robotics, gimbals, and precision axes. |
CAD & Datasheets
2D drawings, datasheets, and STEP/IGES files are shared when the model family and project scope are clear.
Mechanical Integration
Review stator mounting, rotor clamping, air gap, lead wires, and sensor compatibility before sample approval.
Exact Datasheet Fields to Request Before Sample Approval
The table below is not a claim that every configuration has a fixed public catalog value. It is the data package an engineering buyer should request for the selected winding, frame size, and cooling basis before approving samples or CAD release.
| Data Group | Fields | Why Buyers Need It |
|---|---|---|
| Electrical constants | Kt, Km, back EMF constant, phase resistance, phase inductance | Confirms winding fit with bus voltage, drive current, speed ceiling, and tuning assumptions. |
| Mechanical data | OD, ID, stack length, rotor inertia, mass, mounting references, lead exit | Prevents CAD mismatch and helps the buyer validate acceleration and package constraints. |
| Thermal basis | Continuous rating condition, ambient temperature, housing/cooling assumption, insulation class | Separates sustainable torque from short-duration peak torque and avoids heat-path overclaims. |
| Performance curves | Torque-speed curve, efficiency notes, temperature-rise basis, peak torque duration | Lets the buyer compare real operating duty instead of relying on one headline torque number. |
| Inspection records | Resistance, back EMF, insulation / hi-pot, visual check, outgoing record format | Supports sample acceptance, supplier qualification, and repeat-order traceability. |
RFQ Checklist
- Target outside diameter, inside diameter, stack length, and available mounting envelope.
- Continuous torque, peak torque, target speed, duty cycle, and expected motion profile.
- DC bus voltage, current limit, cooling method, ambient temperature, and insulation requirement.
- Lead wire, connector, Hall, encoder, resolver, or bare motor integration requirements.
- Prototype quantity, annual forecast, target delivery country, and requested timeline.
Risk Controls
- Continuous torque is overstated without a real heat path: Request the cooling condition, winding temperature limit, and test basis in the RFQ response.
- Rotor and stator are difficult to install safely: Confirm tooling, air gap, magnet handling, and axial clamping details before sample build.
Product Gallery
Buyer FAQ
Can you customize a frameless torque motor for our housing?
Yes. Share OD, ID, stack length, mounting method, torque-speed targets, voltage/current limits, and sensor requirements so engineering can review a custom path.
Do you provide CAD and datasheet files?
Standard drawings and datasheet files can be shared during RFQ. STEP or IGES files are provided when the mechanical interface and project scope are clear.
Related Resources
Inquiry Email
Include target torque/speed, quantity, and delivery location.