Manufacturing overview · Typical process
Ø37 mm spur gearbox · 12 / 24 V · about 10–1,000 rpm output · ratios 1:10–1:500
A low-cost, compact drive used in smart curtains and locks, small robots and vehicles, vending and dispensing machines, valves and household appliances. A ferrite permanent-magnet brushed motor drives a multi-stage spur gearbox. Quality is decided by the commutation system (commutator turning, brushes and run-in) and by gear accuracy and grease, which together set noise, life and current draw.
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Click a model for full specifications and curves.
| Model | Voltage | Rated power | Rated torque | Rated speed | Current | Rated efficiency | Body length |
|---|---|---|---|---|---|---|---|
| GM37-555PM (1:30) | 12 V | 6.26 W | 0.412 N·m | 145 rpm | 0.848 A | 61.5 % | 78.5 mm |
| JGB37-520 (1:30) | 12 V | 1.38 W | 0.0883 N·m | 150 rpm | 0.228 A | 50.6 % | 55 mm |
| 63ZY125-2440 | 24 V | 151 W | 0.45 N·m | 3,201 rpm | 9.29 A | 67.6 % | 125 mm |
| 80ZY125-2435 | 24 V | 220 W | 0.7 N·m | 2,998 rpm | 12.1 A | 76 % | 125 mm |
| TRS-555PM-2440 | 24 V | 7.34 W | 0.0196 N·m | 3,575 rpm | 0.508 A | 60.2 % | 57 mm |
| GMP36-555PM (1:51) | 24 V | 3.7 W | 0.589 N·m | 59.9 rpm | 0.369 A | 41.7 % | 97.5 mm |
| KM-22X180 (1:64) | 24 V | 2.65 W | 0.147 N·m | 172 rpm | 0.171 A | 64.7 % | 59.5 mm |
| KM-4058F555 (1:58) | 24 V | 2.45 W | 0.39 N·m | 60 rpm | 0.238 A | 43 % | 57 mm |
12 main assembly steps. Each step lists its key equipment and instruments, their main suppliers, and the technical control points.
Armature laminations are punched in a progressive die and interlocked or riveted into the core.
Technical control points:
The core and commutator are pressed onto the shaft, and the core is insulated by epoxy powder coating or insulating end plates plus slot paper.
Technical control points:
Coils are wound by a flyer winding machine and the wire is hooked onto each commutator tang between coils.
Technical control points:
Each hook is fused (hot-staked) onto the wire, which burns off the enamel and makes the joint.
Technical control points:
Every armature is checked for open or shorted coils and insulation to the shaft.
Technical control points:
The commutator is diamond-turned to size and roundness, and copper burrs between bars are brushed away.
Technical control points:
The armature is balanced, usually by milling or drilling small amounts from the lamination teeth.
Technical control points:
Ferrite arc magnets are fitted into the steel can with clips or adhesive and magnetized in place.
Technical control points:
Bushings are pressed into can and end cap, the armature is inserted, and the brush end cap is fitted with brushes held back until the commutator is in place. The can tabs are then staked.
Technical control points:
Motors are run in both directions so the brushes bed to the commutator, then tested at no load.
Technical control points:
The motor pinion is pressed on, gears, pins and the output shaft are assembled into the gearbox with the specified grease, and the gearbox is fixed to the motor.
Technical control points:
Each gear motor is tested for speed, current and noise at the output before packing.
Technical control points:
Suppliers are representative examples (international / mainland China), not an exhaustive or endorsed list.
Progressive stamping and in-die interlocking of stator and rotor laminations.
Selection criteria: Tonnage 60–200 t, 200–800 spm, bottom-dead-centre accuracy.
Used in: 1. Armature lamination stamping
Equipment page →Forms and interlocks laminations; determines core accuracy and burr.
Selection criteria: Number of stations, regrind interval, stack-height control method.
Used in: 1. Armature lamination stamping
Equipment page →Verifies dimensions, geometry and runout.
Selection criteria: Measurement uncertainty, probing system.
Used in: 1. Armature lamination stamping
Equipment page →Rotor-to-shaft and bearing press-fits with force–displacement monitoring.
Selection criteria: Force / displacement resolution, curve evaluation windows.
Used in: 2. Shaft, commutator & core insulation, 9. Motor assembly, 11. Gearbox assembly
Equipment page →Coats the slots and end faces of small stator cores with an insulating epoxy layer (fluidized bed or electrostatic), replacing slot liners.
Selection criteria: Coating thickness control, masking of the bore and tooth tips, preheat and cure temperature, cycle time.
Used in: 2. Shaft, commutator & core insulation
Equipment page →Winds the coils of brushed-motor armatures with one or two flyers and hooks the wire onto the commutator tangs between coils.
Selection criteria: Number of flyers, slot and commutator-bar count range, wire size range, hooking reliability, changeover time.
Used in: 3. Armature winding
Equipment page →Joins enamelled wire to terminals without pre-stripping.
Selection criteria: Closed-loop control of current, force and time; joint monitoring.
Used in: 4. Commutator fusing
Equipment page →Winding resistance, turn-to-turn insulation, hipot and insulation resistance.
Selection criteria: Surge voltage, waveform-comparison algorithm, test cycle time.
Used in: 5. Armature test
Equipment page →Finish-turns the commutator surface of the wound armature with a diamond tool to the required roundness and surface finish, then brushes away copper burrs.
Selection criteria: Runout and bar-to-bar step achievable, surface roughness, centring method (between centres or on bearing seats), cycle time.
Used in: 6. Commutator turning
Equipment page →Measures and corrects rotor unbalance (material removal or addition).
Selection criteria: Minimum achievable residual unbalance, balance grade (e.g. G2.5 / G6.3).
Used in: 7. Armature balancing
Equipment page →Applies adhesive for bonding rotor magnets.
Selection criteria: Shot-volume accuracy, 1K / 2K adhesive capability.
Used in: 8. Magnet fitting & magnetizing, 11. Gearbox assembly
Equipment page →Multi-pole magnetizing of rotor magnets, followed by surface-field measurement.
Selection criteria: Stored energy, peak current, fixture pole count and cooling.
Used in: 8. Magnet fitting & magnetizing
Equipment page →No-load, load, T–N curve, efficiency, back-EMF and Hall-phase testing.
Selection criteria: Torque range and accuracy, speed range, data acquisition.
Used in: 10. Run-in & motor test, 12. Gear motor end-of-line test
Equipment page →Main raw materials, purchased components and auxiliary materials. ★ marks items critical to performance or cost. Quantities are typical and vary by model.
| Part | Class | Material | Key specification | Qty | Supply chain / regions | Representative suppliers | Process | Tests |
|---|---|---|---|---|---|---|---|---|
| Armature laminations | Raw material | Non-oriented Electrical Steel | 0.5 mm 50W800 or cold-rolled low-carbon steel for low-cost versions | Per stack height | Mills are outside the Pearl River Delta (Baosteel, Shougang, Ansteel); Pearl River Delta buyers get slit coil from mill service centres and steel distributors in Foshan (Lecong) and Dongguan, or buy finished cores from stamping houses. Ask for the mill certificate with every coil. | WcanFoshan, HongwangFoshan, Fulwealth SteelDongguan+3 more → | Process → | View → |
| ★Armature winding | Raw material | Enamelled Copper Wire | Polyurethane or polyester-imide, Ø0.2–0.5 mm | 5 coils | The Pearl River Delta has its own enamelled-wire makers in Zhuhai, Foshan, Jiangmen and Huizhou, alongside the big Anhui and Jiangsu producers. Local supply shortens lead time; still audit the thermal class and in-line test records per spool. | RonsenZhuhai, Jingda GuangdongFoshan, Suntek WireJiangmen+2 more → | Process → | View → |
| ★Magnets | Raw material | Sintered Ferrite Magnet (arc segment) | Sintered anisotropic strontium ferrite arcs, e.g. Y30BH | 2 | Jiangmen is one of China's main ferrite-magnet bases, with more makers in Dongguan; Hengdian (Zhejiang) remains the largest. For arc segments, check the arc and chord tolerances and grinding chips at the edges. | Courage MagnetDongguan, MagsourceJiangmen, JPMF JiangyiJiangmen | Process → | View → |
| Motor can | Raw material | Deep-drawn Steel Motor Can | Deep-drawn DC04 / SPCC, zinc or nickel plated | 1 | Dongguan, Shenzhen and Huizhou have deep-drawing stampers making motor cans close to the small-motor clusters. Check wall-thickness uniformity after drawing and the roundness of the bearing pocket. | HejuDongguan, Hongyuan HaojinShenzhen, RongguangHuizhou | Process → | View → |
| ★Commutator | Purchased component | Commutator (hook type) | 5-bar hook-type, copper segments in phenolic moulding | 1 | Shenzhen and Dongguan host commutator makers including a listed specialist, alongside the big Zhejiang and Jiangsu producers. Ask for over-speed (spin) test results and bar-to-bar insulation data. | HuanxiangDongguan, KaizhongShenzhen, SOMPShenzhen | — | View → |
| ★Brushes & brush end cap | Purchased component | Carbon Brushes & Brush Gear | Copper-graphite or carbon brushes, brass holders, PBT / PA end cap (UL 94 V-0 where required) | 1 set | Guangzhou, Zhuhai and Dongguan have carbon-brush and brush-holder makers, including Japanese-invested plants. Match brush grade to current density and commutator speed, and test wear on your own motor. | Fuji CarbonGuangzhou, EckerleZhuhai, LinhengDongguan+1 more → | — | View → |
| Motor shaft & output shaft | Raw material | Motor Shaft | Ground carbon or stainless steel; Ø6 mm D-cut output, hardened | 2 | Dongguan is the Pearl River Delta centre for precision turned and ground shafts, with many CNC-turning and centreless-grinding shops serving the local motor industry. Check the h6 bearing-seat grinding capability and run-out inspection, not just turning. | Sanfeng ShaftsDongguan, LongmingDongguan, DayueDongguan | Process → | View → |
| ★Motor bushings | Purchased component | Oil-impregnated Sintered Bushing | Oil-impregnated sintered bronze, self-aligning type | 2 | Dongguan's powder-metallurgy plants make oil-impregnated bushings for small motors in high volume. Check oil content, porosity and the bore size after press-fit. | Jingsheng PMDongguan, Qiantong PMDongguan, Ningzhi PMDongguan | — | View → |
| Output bearings | Purchased component | Deep-groove Ball Bearing | Small deep-groove ball bearings (sintered bushings on low-cost versions) | 1–2 | Bearing factories are mostly outside the Pearl River Delta (Zhejiang, Liaoning, Henan, Japan); the Pearl River Delta has brand sales offices in Guangzhou and Shenzhen and local makers of miniature bearings in Dongguan and Shenzhen. Buy branded bearings only through authorised channels to avoid counterfeits. | NSKGuangzhou, Fitrun BearingDongguan, Kentie BearingDongguan+6 more → | Process → | View → |
| ★Gears | Purchased component | Gearbox Gears (sintered steel / plastic) | First stage POM or PA66, later stages sintered steel (e.g. Fe-Cu-C) or hobbed steel; motor pinion steel or plastic | 1 set | Dongguan has a dense powder-metallurgy and plastic-gear cluster, and Shenzhen has gearbox specialists for micro gear motors. Ask for gear-roll test data and noise checks on assembled gearboxes. | Jingsheng PMDongguan, Qiantong PMDongguan, UT GearShenzhen+1 more → | Process → | View → |
| Gearbox housing | Raw material | Die-cast Aluminium End Cap | Die-cast zinc or aluminium housing, or stamped steel plates with spacer pillars | 1 set | Foshan, Zhuhai and Dongguan have many high-pressure die-casters, from listed auto-parts groups to small motor-cap shops. Ask for X-ray porosity checks at the bearing seat and whether machining is done in-house. | JinjuqiweiFoshan, WencanFoshan, KingrunZhuhai+1 more → | Process → | View → |
| ★Gearbox grease | Auxiliary material | Gearbox Grease | Synthetic grease compatible with plastic gears, rated for the temperature range | As required | Dongguan, Foshan and Shenzhen have domestic grease makers next to Pearl River Delta offices of German and Japanese specialty brands. Check low-temperature torque and compatibility with plastic gears. | BaoxingDongguan, CaidonFoshan, HechengShenzhen+1 more → | — | View → |
| Armature insulation | Auxiliary material | Insulation Bobbin & Slot Liner | Epoxy powder coating, or insulating end plates plus slot paper | 1 set | Shenzhen and Huizhou have makers of insulation films, sleeving and moulded bobbins; slot liners (DMD, NMN, PET film) are also stocked by Dongguan distributors. Confirm the thermal class matches the insulation system and keep UL file numbers on record. | FuweiHuizhou, WoerShenzhen, JDDShenzhen | Process → | View → |
| Terminals & leads | Purchased component | Lead Wires & Connectors | Solder tabs or leads with connector per customer | 1 set | Shenzhen and Dongguan are a major cluster for wire, harness and connector makers, including offices of international connector brands. Ask for crimp-force monitoring and pull-test records on terminated leads. | MolexShenzhen, WoerShenzhen, XSD CableDongguan+2 more → | Process → | View → |
| Fasteners & small parts | Auxiliary material | Fasteners & Small Parts | Gearbox screws, gear pins, washers, magnet clips | 1 set | Dongguan and Shenzhen have many fastener makers and specialists in retaining rings and wave washers for small motors, so standard parts no longer have to come from Wenzhou or Ningbo. Check plating and hardness certificates per lot. | JinyiDongguan, LiangguDongguan, Lock TechnologyShenzhen+3 more → | Process → | View → |
How each key raw material and purchased component is made: process steps, the equipment and instruments used at each step with their main suppliers, and the technical control points. Click a material to expand.
Steelmaking & vacuum degassing → Hot rolling → Pickling & cold rolling → Continuous annealing → Insulation coating → Testing & slitting
Hot metal is refined in a converter, then RH-degassed to ultra-low carbon; silicon and aluminium are added to the target grade.
Technical control points:
Slabs are reheated and rolled into hot-rolled coils of about 2 mm.
Technical control points:
Scale is removed and the strip is cold-rolled to final gauge (0.50 / 0.35 mm).
Technical control points:
Recrystallization annealing in a protective atmosphere grows grains to the size that minimises core loss.
Technical control points:
A thin inorganic / organic insulation coating is applied and cured to limit interlaminar eddy currents and aid punchability.
Technical control points:
Magnetic properties are tested per coil, then coils are slit to the stamping width.
Technical control points:
Rod drawing → In-line annealing → Enamelling & curing → Lubrication, in-line testing & spooling
8 mm oxygen-free copper rod is drawn through successive diamond dies to the target diameter.
Technical control points:
Resistance annealing restores ductility after drawing.
Technical control points:
Base coat (polyesterimide) and overcoat (polyamide-imide) are applied in many thin passes, each cured in the oven.
Technical control points:
A surface lubricant is applied for winding, diameter and film faults are tested continuously, and wire is spooled.
Technical control points:
Mixing & calcining → Wet milling → Wet pressing in a magnetic field → Sintering → Grinding → Final inspection
Iron oxide is mixed with strontium (or barium) carbonate and calcined in a rotary kiln into ferrite clinker.
Technical control points:
Clinker is milled in water with additives (CaCO₃, SiO₂) to a fine slurry.
Technical control points:
The slurry is pressed in a die under a magnetic field to align the particles, while water is drawn off by vacuum. This makes the magnet anisotropic.
Technical control points:
Green parts are sintered in air in a roller or tunnel kiln and shrink to near-final size.
Technical control points:
Inner and outer arcs, ends and chamfers are ground to size.
Technical control points:
Magnetic properties, dimensions and appearance are checked before packing.
Technical control points:
Blanking & deep drawing → Piercing, flanging & trimming → Cleaning & plating
Low-carbon steel strip is blanked and drawn into a can in several stages.
Technical control points:
Bushing boss, vent and mounting holes, tabs and the open edge are formed in the same transfer or progressive die.
Technical control points:
Cans are degreased and zinc or nickel plated (or blackened) for corrosion protection.
Technical control points:
Bar cutting → CNC turning & keyway / D-cut → Heat treatment → Cylindrical grinding → Cleaning, rust protection & inspection
Cold-drawn or ground bar stock (SUS420J2 / C45) is cut to length.
Technical control points:
Shoulders, grooves and the shaft extension are turned; the keyway or D-cut is milled.
Technical control points:
Quench and temper (or induction hardening of bearing seats) for strength and wear resistance.
Technical control points:
Bearing seats and the shaft extension are ground to h6 tolerance.
Technical control points:
Parts are cleaned, rust-protected and inspected before packing.
Technical control points:
Ring forging & turning → Heat treatment → Grinding → Superfinishing → Cleaning, assembly, greasing & sealing → Vibration & noise test
GCr15 (52100) bearing steel is forged or turned into ring blanks.
Technical control points:
Through-hardening and tempering to about HRC 60–64.
Technical control points:
Faces, outer diameter, bore and raceways are ground.
Technical control points:
Raceways are superfinished for low roughness and low noise.
Technical control points:
Rings and balls are cleaned, matched for clearance, assembled with the cage, greased and shielded.
Technical control points:
Every bearing is spun and its vibration measured to classify the grade.
Technical control points:
Mixing & compacting → Sintering → Sizing → Heat treatment → Final inspection
Iron-based powder (e.g. Fe-Cu-C) is mixed with lubricant and compacted into gear shapes.
Technical control points:
Compacts are sintered in a protective atmosphere, bonding the particles.
Technical control points:
Sintered gears are re-pressed in a sizing die to improve accuracy and surface finish.
Technical control points:
Highly loaded output-stage gears are case-hardened or steam-treated for wear resistance.
Technical control points:
Gears are checked for composite deviation, bore size and appearance.
Technical control points:
Melting & degassing → High-pressure die casting → Trimming & porosity inspection → CNC machining
ADC12 ingot is melted and degassed to reduce hydrogen porosity.
Technical control points:
Molten alloy is injected into the steel die at high speed and pressure.
Technical control points:
Gates and overflows are trimmed; castings are sampled by X-ray for porosity.
Technical control points:
Bearing seat, spigot and mounting faces are finish-machined.
Technical control points:
Resin drying → Injection moulding → Inspection
PA66+GF pellets are dried before moulding.
Technical control points:
Bobbins (end plates) are moulded, optionally with insert-moulded terminals.
Technical control points:
Dimensions, appearance and flammability conformance are checked.
Technical control points:
Cut, strip & crimp → Crimp verification → Housing insertion & continuity test
Wires are cut and stripped, and terminals crimped automatically.
Technical control points:
Cross-sections and pull tests verify each setup and lot.
Technical control points:
Terminals are inserted into connector housings and the harness is continuity-tested.
Technical control points:
Cold heading & thread rolling → Heat treatment & surface treatment → Optical sorting
Wire is cold-formed into screw blanks and threads are rolled.
Technical control points:
Parts are hardened as required, then zinc-plated or passivated.
Technical control points:
100% sorting removes dimensional and visual defects.
Technical control points:
Materials without a process here (bought-in chemicals, chips and some purchased components) are covered by incoming inspection and approval tests only.
Material-level tests are used for incoming inspection and supplier approval (PPAP / sample approval); motor-level tests for product validation (DV / PV). Conditions and criteria depend on the application and customer specification.
Applies to: Armature laminations
Applies to: Armature winding
Applies to: Magnets
Applies to: Motor can
Applies to: Commutator
Applies to: Brushes & brush end cap
Applies to: Motor shaft & output shaft
Applies to: Motor bushings
Applies to: Output bearings
Applies to: Gears
Applies to: Gearbox housing
Applies to: Gearbox grease
Applies to: Armature insulation
Applies to: Terminals & leads
Applies to: Fasteners & small parts
| Test | Standard / condition |
|---|---|
| High-temperature operation and low-temperature start | IEC 60068-2-1 / -2-2 |
| Temperature cycling / thermal shock | IEC 60068-2-14 |
| Damp heat, steady state (e.g. 85 °C / 85% RH) | IEC 60068-2-78 |
| Salt spray | IEC 60068-2-11 |
| Sinusoidal / random vibration | IEC 60068-2-6 / -2-64 |
| Mechanical shock | IEC 60068-2-27 |
| Temperature-rise test | IEC 60034-1 |
| IP protection rating | IEC 60529 |
| Hipot and insulation resistance | IEC 60034-1 |
| Locked rotor and overload | Per customer specification |
| Endurance test (continuous rated load) | Per customer specification, typically 3,000–20,000 h |
| Noise and vibration | ISO 1680, IEC 60034-14 |
Low-voltage motor without electronics: Assumes a low-voltage motor (up to 48 V) without built-in electronics, exported as a component. An integrated driver or the end use (medical, automotive…) changes the requirements.
Listed alphabetically, not in order of preference. Confirm accreditation scope with each body.
Cost analysis, supplier sourcing and audits, production-line planning and equipment selection, and export certification planning — consulting by a senior motor engineer.
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