Performance Curves
Request torque-speed, efficiency, and temperature-rise data for the quoted winding and cooling condition.
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Large Hollow-Shaft Torque Motors
Large-aperture direct-drive motor kits for gimbals, rotary tables, cable pass-through axes, and precision indexing systems.
Target Buyer:Best for equipment builders that need a large aperture, smooth rotary control, and factory-side customization coordination.
Capability Highlights
- Large inside diameter for optics, cables, slip rings, or tooling access.
- Direct-drive architecture reduces backlash from gear stages.
- Custom mechanical interface and winding support for heavy-duty OEM axes.
Typical Applications
- Optical gimbals, antenna pointing, and stabilized payload platforms
- Rotary tables, indexing axes, and inspection equipment
- Cable-through precision automation modules
Engineering Focus
- Confirm radial and axial package limits before electromagnetic sizing.
- Define thermal path and cooling method because larger motors can be heat limited.
- Coordinate rotor retention and installation tooling for safe handling.
Key Evaluation Matrix
| Metric | Typical Range | Why It Matters |
|---|---|---|
| Inside diameter | Custom large-aperture geometry by project | Determines whether optics, cables, slip rings, or shafts can pass through the axis. |
| Runout-sensitive integration | Depends on customer bearing and housing design | Mechanical accuracy often determines final pointing or indexing quality. |
| Thermal capacity | Natural convection, conduction, or active cooling | Sets sustainable torque in enclosed gimbal or table applications. |
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
- Large rotor magnet handling creates assembly hazards: Review installation tooling, safety distance, and fixture plan before sample shipment.
- Application accuracy depends on surrounding mechanics: Separate motor data from bearing, encoder, and structural tolerance assumptions.
Product Gallery
Buyer FAQ
Can you make a motor with a larger through-hole?
Yes. Provide minimum ID, maximum OD, stack length, torque-speed duty, and cable or optics routing constraints for review.
Is a hollow-shaft torque motor suitable for gimbals?
It can be a strong fit when cable routing, smooth motion, low backlash, and thermal control are key requirements.
Related Resources
Inquiry Email
Include target torque/speed, quantity, and delivery location.