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Products
Plantary Reducer Gear – Precision Gear for Robot | DD Gear
Product Details
FAQ
Features & Benefits
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High torque density in a compact package
Multiple planets share the load and contact area, allowing planetary reducers to transmit high torque within a small diameter and length, ideal for robotic joints and servo axes. -
Low backlash and precise positioning
With precision-cut or ground teeth, controlled clearances, and proper preloading in the gearbox, planetary reducers can reach low backlash suitable for servo positioning and path control in robots. -
High efficiency and smooth running
Planetary gear trains provide good efficiency because torque is shared among several meshes and sliding losses are reduced. Helical planetary stages can further improve smoothness and reduce noise for sensitive applications. -
Scalable reduction ratios
Single-stage planetary reducers commonly provide ratios roughly between 3:1 and 10:1; multiple stages can be combined to reach higher ratios while keeping the package compact. -
Flexible layouts for robot joints
Planetary reducer gears can be configured for in-line servo gearheads, right-angle stages (with additional gearsets), or integrated joint modules, allowing designers to place high-torque actuators close to or inside the joint. -
Custom materials and heat treatment
DD Gear selects materials and heat treatment (carburizing, nitriding, or Q&T) according to robot joint torque spectra, duty cycles, and target service life, balancing tooth root strength, pitting resistance, and stiffness. -
From prototypes to series production
We support small prototype batches for actuator development and robot pilot builds, then transition to controlled mass production with stable quality and full inspection documentation.
Technical Specifications
Final values will be defined according to the customer’s drawing, reduction ratio, and robot joint load cases.
| Item | Typical Option |
| Gear Type | Planetary reducer gear components (sun, planet, ring gears, associated spur/helical gears) |
| Module (m) | Approx. 0.3 – 2.5 (small-module range typical for robot actuators; actual per drawing) |
| Material | Carburizing steels and alloy steels suitable for high contact stress and fatigue (e.g. 16MnCr5 / 20CrMnTi / 20CrMo equivalents, others on request) |
| Heat Treatment |
Carburizing & quenching, nitriding, or quench-and-temper; optional shot peening and stress improvement for higher fatigue life |
| Surface Hardness | Typically 58–62 HRC (carburized) or per drawing |
| Accuracy | High-precision internal and external gear tolerances per ISO / DIN / JIS; class defined together with customer |
Applications
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Robot arm and manipulator joints
Planetary reducers used in servo gearheads or joint modules to provide compact, high-torque output and accurate positioning at shoulder, elbow, and wrist axes. -
Collaborative robots (cobots)
Low-backlash planetary reducers paired with servo motors for smooth, compliant motion and precise force control in human-robot collaborative environments. -
AGV / AMR wheel modules and drive units
Planetary reducers integrated in wheel drives to deliver high torque at low speed, with compact radial and axial dimensions. -
Precision positioning systems
Linear and rotary axes, pick-and-place modules, and small machine tools using planetary servo gearheads where high torque density and minimal backlash are needed. -
Industrial automation gearmotors
Planetary gearmotors used across conveyors, packaging equipment, and inspection systems where space is limited but torque and precision demands are high.
Gear Manufacturing Process
Every planetary reducer gear component is produced under a controlled gear manufacturing route designed for precision and durability. A typical process flow is:
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Blank preparation – forging, ring rolling, or bar cutting of sun, planet, and ring gear blanks
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Turning – CNC machining of reference diameters, faces, bores, and hubs
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Gear cutting – hobbing, shaping, or skiving for external and internal gears
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Auxiliary machining – drilling, milling of keyways, bolt patterns, lubrication features, and reference surfaces
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Heat treatment – carburizing & quenching, nitriding, or Q&T according to tooth loading and life requirements
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Shot peening / stress relief – optional to improve tooth root strength and fatigue resistance
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Finish machining – grinding of reference surfaces, bores, and critical diameters
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Gear finishing – gear grinding or honing (where required) for high accuracy and smooth meshing
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Cleaning & anti-rust treatment – for clean assembly into precision gearboxes and actuators
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Final inspection & packaging – according to the agreed control plan
Precision Gear Customization Process
To support custom planetary reducer gear projects, DD Gear follows a clear, eight-step customization process:
Step 1 – Requirement Collection
Customers provide design requirements, 2D drawings, 3D models, or physical samples, together with basic duty cycle information (torque, speed, life, installation).
Step 2 – Drawing Design & Optimization
Based on the provided drawings or samples, DD Gear prepares or optimizes detailed manufacturing drawings and shares them with the customer for confirmation.
Step 3 – Quotation
After the drawings and technical points are confirmed, we issue a precise quotation covering tooling, piece price, lead time, and quality requirements.
Step 4 – Tooling & Fixture Preparation
Once the price is confirmed, we arrange tooling and fixture production. Any tooling cost is agreed with the customer in advance and can be offset or refunded after mass orders, according to the commercial agreement.
Step 5 – First Sample Approval
After tooling and fixtures are ready, we manufacture the first sample batch—typically within about 30 days—and ship it to the customer for testing.The customer inspects and validates the samples in their gearbox or test bench and provides feedback on dimensions, performance, and any required adjustments.
Step 6 – Mass Production
When the sample is approved, we start mass production according to the agreed production plan and quality standards.
Step 7 – Finished Product Inspection
After production, we inspect hardness, dimensions, runout, tooth accuracy, and other critical characteristics to ensure full compliance with the drawing and standards.
Step 8 – Shipping Arrangement
Once inspection is passed and shipment is approved by the customer, we arrange booking, packaging, and delivery to the specified destination.
Quality Assurance & Inspection
DD Gear applies the same quality philosophy to planetary reducer gear and all precision gears:
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Quality management systems based on ISO 9001 and IATF 16949
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Process control from incoming material to final inspection, including:
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Material certification and chemical composition checks
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Hardness and case depth verification after heat treatment
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Gear measurement for profile, lead, pitch, and runout
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Surface roughness testing on gear flanks and journals
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Dimensional inspection with calibrated gauges and CMMs
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Traceability for each batch with inspection records and reports
- Optional documentation such as PPAP/FAIR packs on request
Packaging
Usage & Installation Notes
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Ensure that sun, planet, and ring gear components are assembled according to the planetary reducer design, with correct clearances and alignment of carriers and bearings.
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Follow the specified backlash and preload settings at gearbox level; excessive preload or incorrect clearances may increase friction, heat, or noise.
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Use the recommended lubricant type and fill level (oil or grease) for the planetary reducer; insufficient or incorrect lubrication can accelerate pitting and wear on fine-pitch teeth.
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Do not exceed rated torque and speed for the planetary stage; long-term overload or repeated shock loading may reduce gear life.
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During maintenance, inspect teeth for wear, pitting, scuffing, or cracks, especially in high-torque joints and axes that see frequent reversals.
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Store finished gears in dry, clean conditions with anti-rust protection and avoid impacts that could damage tooth flanks or reference surfaces.
Company Strength – DD Gear
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Specialized in small module, high-precision gears and shafts for EVs, humanoid robots, AGVs, and intelligent automation.
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Integrated manufacturing from forging and machining to heat treatment and gear grinding.
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Quality systems aligned with automotive standards, with experience supporting OEM and Tier 1 projects.
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Engineering support covering concept feasibility, DFM reviews, and failure analysis feedback.
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Global export capability with experience serving customers in multiple countries.
Q1: What information do you need for a planetary reducer gear quotation?
We normally need 2D drawings (PDF), 3D models (STEP/IGES if available), material and heat treatment requirements, expected annual volume, and basic application data such as robot type, joint torque, target ratio, and life requirements.
Q2: Do you supply complete planetary gearboxes, or only gear components?
DD Gear primarily supplies gear components—sun, planet, and ring gears, as well as related shafts or spur/helical gears. Complete planetary gearboxes and actuators are usually assembled by the customer or their system partners.
Q3: Can you help optimize tooth geometry or material selection?
Yes. Within the constraints of your standards, we can discuss module selection, tooth counts, tooth modifications, and material/heat treatment windows to support low backlash, high torque density, and long fatigue life.
Q4: What accuracy levels can you achieve on planetary reducer gears?
We manufacture internal and external gears to high precision per ISO / DIN / JIS standards. Specific accuracy class, runout, and roughness limits are defined together with you according to joint stiffness and positioning accuracy targets.
Q5: What is your typical lead time for samples and mass production?
Prototype planetary reducer gear sets are usually available in about 2–3 weeks after drawing confirmation and tooling readiness. Mass production lead time depends on quantity and process route and will be confirmed during quotation.
Q6: What is your typical MOQ?
MOQ depends on part complexity and tooling. We support flexible MOQ for development and pilot runs, then align batch sizes with your robotics program’s series production plan.
Q7: Can you provide inspection reports with each batch?
Yes. We can provide dimensional inspection reports, gear measurement charts, hardness and case-depth records, and other documents as required.
Reliable precision gears for robotics, automotive, and beyond.
Custom Gears for Sliding, Swing & Industrial Doors | DD Gear
Automatic Door Gear from DD Gear is a range of custom-designed, small- to medium-module gears and shafts used in automatic sliding doors, swing doors, revolving doors and industrial doors (sectional, rolling, high-speed doors). In these systems, compact electric motors drive gearboxes and gear trains that must deliver high starting torque, smooth motion and very low noise while opening and closing heavy door leaves hundreds or thousands of times per day. Typical automatic door operators use one or more stages of spur and helical gears in combination with worm gears or bevel gears. Spur gears provide simple, efficient torque transfer for intermediate stages. Helical gears, with their angled teeth and higher contact ratio, help achieve quieter and smoother running, which is critical in hotels, hospitals, offices and residential buildings. Worm gears are often used for high reduction ratios and self-locking behavior, improving safety when the door is at rest and reducing backdrive from wind loads or manual pushing. In some operators, bevel gears change shaft direction between the motor, transmission and drive shaft or belt/chain. DD Gear manufactures Automatic Door Gears strictly on a custom, build-to-print basis. Using customer drawings or validated samples, we supply spur and helical pinions and gears, worm gears and worm wheels, bevel gears, gear shafts and related components for door operators. Through appropriate alloy steels, surface treatments, controlled heat treatment and precision machining, DD Gear helps door-operator OEMs and system integrators build drives that provide quiet operation, long life and reliable performance in entrances exposed to dust, temperature changes and frequent cycling.
Custom Precision Gears for Electric Wheelchair | DD Gear
Electric Wheelchair Gear from DD Gear covers a family of small-module, custom-designed gears and shafts used in electric wheelchairs, powered mobility scooters and related assistive devices. In these products, compact electric motors drive wheel-side or centrally mounted gearboxes that must deliver high torque at very low vehicle speed, provide smooth, gentle acceleration and braking, and work reliably for years in both indoor and outdoor environments. Typical electric wheelchairs use a single-speed reduction between the high-speed motor and the drive wheel. This reduction is often realized by a worm gear stage, a spur/helical reduction stage, or a planetary gear set integrated into a wheel-side gearbox. Worm gears are commonly used because they can offer high reduction ratios and inherent self-locking behavior in many designs, helping the chair hold position on slopes when the motor is not powered. Spur and helical gears are used in intermediate stages or in designs where efficiency and low noise are prioritized. Planetary gear trains may be used when high torque density and compact packaging are critical, especially in wheel modules. DD Gear manufactures Electric Wheelchair Gears strictly on a custom, build-to-print basis. Based on customer drawings or validated samples, we supply worm gears and worm wheels, spur and helical gears, planetary gear components (sun, planet, ring), gear shafts and wheel-drive gear elements. Using case-hardening steels, controlled heat treatment and small-module precision machining or grinding, DD Gear helps mobility OEMs and system suppliers design drivetrains that offer quiet operation, safe holding behavior, good efficiency and long service life, enhancing comfort and confidence for end users
Custom Precision Gears for Surgical Robotics | DD Gear
Surgical Robot Gear from DD Gear covers a family of small-module, high-precision gears and shafts used in surgical robots, robotic-assisted surgical systems and related medical robotic platforms. In these applications, compact actuators drive robotic arms, wrists, end effectors and instrument modules that must deliver micron-level positioning, smooth motion and highly repeatable force control, often in minimally invasive procedures around critical anatomy. To achieve this, surgical robots commonly use spur and helical gears, planetary gear sets and gears integrated with harmonic or other precision reducers inside joint and instrument actuators. These gear stages must work with high-resolution encoders and advanced control algorithms, providing low backlash, high torsional stiffness and consistent friction characteristics across the full range of motion. At the same time, many components operate near the sterile field and must tolerate frequent cleaning and sterilization cycles, use biocompatible or low-outgassing materials and lubricants, and minimize particle generation. DD Gear manufactures Surgical Robot Gears strictly on a custom, build-to-print basis. Based on your drawings or validated samples, we supply spur, helical and bevel gears, planetary components (sun/planet/ring), gear shafts, small-module pinions and interface gears for precision reducers, using carefully selected alloy steels, stainless steels and, where specified, non-magnetic or corrosion-resistant materials. With controlled heat treatment, precision machining and (when required) ground tooth flanks, DD Gear supports surgical robot OEMs and system suppliers in building actuators that deliver precise, smooth and reliable motion, while supporting cleaning and sterilization concepts defined at the system level.
Custom Precision Gears for Automated Guided Vehicles | DD Gear
AGV Gear from DD Gear refers to a range of custom, small-module gears and shafts specifically engineered for Automated Guided Vehicles (AGV) and Autonomous Mobile Robots (AMR) used in warehouses, factories, distribution centers and logistics hubs. In these applications, compact electric motors drive wheel-mounted or centrally mounted gearboxes that must deliver high torque at low travel speed, provide smooth, precise motion control, and withstand continuous start/stop cycles in 24/7 intralogistics operations. Typical AGV drivetrains combine motor + reduction gearbox + drive wheel, often in a wheel hub or wheel-side gearbox design, while steering and lifting functions may use additional gear stages or screw drives. Single- or multi-stage spur and helical gears are common in wheel drives and intermediate stages, while planetary gear sets are widely used where high torque density and compact packaging are required, such as in drive wheels for heavy loads or AGV forklifts. In some architectures, gears are also combined with chain or belt stages to reach the final wheel or mast. Compared with traditional industrial vehicles, AGV/AMR systems place greater emphasis on low noise, smooth operation, positioning accuracy and long maintenance intervals. DD Gear manufactures AGV gears strictly on a custom, build-to-print basis, supplying spur and helical gears, planetary gear components (sun/planet/ring), bevel gears, gear shafts and wheel-drive gear elements based on customer drawings or validated samples. Using case-hardening steels, controlled heat treatment and small-module precision machining or grinding, DD Gear supports AGV and AMR OEMs in building transmissions that provide high efficiency, compact size, low NVH and long service life in demanding indoor and outdoor logistics environments.
Custom Reduction Gears & Shafts for E-Motorcycle | DD Gear
E-Motorcycle Gear from DD Gear refers to a range of small-module reduction gears and shafts engineered for electric motorcycles, e-scooters, e-mopeds and high-power e-bikes. Instead of multi-speed gearboxes like those used in traditional ICE motorcycles, most electric two-wheelers use a single-speed reduction between the high-speed electric motor and the wheel. This reduction can be realized by hub-motor planetary gear sets, mid-drive spur/helical gear stages, or a combination of gear reduction + chain or belt drive. In hub-motor architectures, a compact planetary gear train is often integrated inside the wheel hub to reduce motor speed and increase wheel torque while keeping unsprung mass and noise under control. In mid-drive or centrally mounted motor layouts, the motor drives an intermediate shaft via spur or helical gears, and torque is then transferred to the rear wheel by a chain or belt. In both cases, the gears must handle high input speeds, frequent acceleration/deceleration, high torque at low road speed, outdoor exposure and strict NVH requirements, all within tight packaging envelopes. DD Gear manufactures E-Motorcycle Gears strictly on a custom, build-to-print basis. Using customer drawings or validated samples, we supply spur and helical pinions and gears, planetary gears (sun/planet/ring), gear shafts and hub-motor gear components. With appropriate case-hardening steels, controlled heat treatment and small-module precision machining or grinding, DD Gear helps electric two-wheeler OEMs and system suppliers build drivetrains that deliver high efficiency, quiet operation, compact packaging and long service life, supporting both urban commuting and higher-performance applications
Custom Precision Gears for Packaging Machinery | DD Gear
Packaging Machinery Gear from DD Gear is a family of small- to medium-module, custom-designed gears used in form-fill-seal (FFS) machines, cartoners, case packers, palletizers, labelers and conveyor systems. In modern packaging lines, gears are responsible for coordinating motion between film feed, sealing jaws, product infeed, carton erection, filling, closing and outfeed. They must operate at high speed, often in 24/7 duty, while maintaining precise timing and position to avoid film waste, misaligned seals, product jams and unplanned downtime. Most packaging mechanisms rely on spur and helical gears in gearboxes and timing stages for parallel shafts. Spur gears provide simple, highly efficient torque transmission and are widely used in indexing, feed and cam drives. Helical gears, with their angled teeth and higher contact ratio, offer smoother, quieter running and higher load capacity, which is important in high-speed packaging halls where noise and vibration affect both productivity and operator comfort. In right-angle or compact layouts, bevel gears, worm gears or planetary sets may be used to change direction or achieve higher reduction ratios in a limited envelope. DD Gear manufactures Packaging Machinery Gears strictly on a custom, build-to-print basis. Based on your drawings or validated samples, we supply precision spur, helical, bevel gears, gear shafts and internal gears, using case-hardening steels, nitriding steels, stainless or corrosion-resistant grades, and selected engineering plastics where appropriate. Through controlled heat treatment, finishing and systematic quality control, we help packaging OEMs and retrofitters build gear trains that deliver stable speed ratios, smooth motion, low noise and long service life, even in demanding environments involving dust, humidity or washdownExploring The Science of Precision Gears
What Makes a Gear Efficient: Understanding Key Structure Basics
Machines today run faster, lift more, and squeeze into tighter spaces than anyone thought possible a few years ago. At the center of almost every one of them sits a gear (sometimes no bigger than a coin, sometimes the size of a dinner table). Get the gear right, and the whole system hums along quietly for years. Get it wrong, and you burn power, make noise, and watch parts wear out way too soon. The Fundamental Role of Gears in Modern Machinery Gears do one basic job: take the speed and twist coming out of a motor and turn it into exactly the speed and push the machine needs. The trick is doing that job while wasting as little energy as possible and staying tough enough to last. Modern gear sets face demands that would have broken old designs in weeks: Motors that spin 15,000 rpm or higher all day long. Robot arms that have to stop dead-on within a hair’s width every single time. Warehouse robots that start and stop thousands of times a shift while hauling a ton or more. Everything is packed smaller, lighter, and quieter than the last generation. Core Structural Components Defining Gear Performance The real difference between a cheap gear and a great one shows up in three places: tooth profile, metal choice and heat treatment, and how accurately the part is made. Tooth Profile and Engagement The curve and angle of each tooth decide how smoothly power moves from one gear to the next. Spur gears are simple and cheap, but the teeth slam together all at once. That bang turns into noise and vibration, especially once speeds climb. Helical gears fix most of that by cutting the teeth on a slant. One tooth starts touching before the last one leaves, so the handover is gradual and quiet. The downside is a little side thrust, but good bearings handle it easily. Even helical gears can whine if they’re not shaped exactly right. That’s why high-end makers add tiny crowning, tip relief, and lead corrections. Those little tweaks, often just a few microns, spread the load evenly, no matter how much torque you throw at the gear. Result? Far less noise and longer life. Surface finish matters too. A ground and polished flank can cut friction losses enough to add a percent or two to overall drivetrain efficiency (real money when you’re talking about an electric truck fleet). Material Science and Durability A gear tooth sees huge bending stress at the root and crushing stress at the pitch line every single rotation. Pick the wrong steel, and it pits or snaps. Most heavy-duty gears today start life as forgings of alloys like 18CrNiMo7-6 or 20MnCr5. Then comes carburizing: pack carbon into the surface, quench it hard (usually 58–62 HRC), but leave the core tougher (around 35–45 HRC). The hard skin laughs at wear; the softer middle soaks up shock without cracking. A well-controlled carburizing run can push case depth within 0.05 mm every time, and that consistency is what lets a gear set survive three to five years of round-the-clock running instead of failing the first winter. Module and Precision The module is just tooth size. Big module = big teeth = can carry big loads, but needs big space. Small module (0.3–0.8 is common now) lets you pack huge reduction ratios into a coffee-cup-sized box. But tiny teeth are unforgiving. A couple of microns of shape error, and the gears howl or wear out fast. That’s why top shops grind every tooth after heat-treat and check them on machines that measure to one micron or less. Anything better than ISO Grade 5 is good; Grade 4 or higher is what robots and EVs demand. Diversity in Design: Key Gear Types and Functions Cylindrical Gears: Spur and Helical Spur gears are the old reliable for parallel shafts. Simple, cheap, 98–99% efficient. Helical gears cost more but run quieter and carry heavier loads in the same space. Almost every electric car gearbox and robot joint uses helical gears somewhere in the train. High-Ratio & Compact Designs: Planetary and Worm Gears Planetary sets give you a 100:1 reduction in one compact package (sun, planets on a carrier, outer ring). Perfect for robot elbows and AGV wheels that need massive torque without a huge motor hanging off the side. Worm gears turn 90 degrees and can hit crazy ratios in one stage. They also self-lock (wheel won’t spin the worm backward), so they’re great for lifts and gates that have to stay put when power is off. Angular Transmission: Bevel Gears Need power to turn a corner? Bevel gears do it. Straight bevels are noisy; spiral and hypoid versions run smoothly and strongly. You’ll find them in car differentials and right-angle robot drives. The Demands of Next-Generation Applications Robotics and Zero-Backlash Requirements Robot joints can’t have even one arc-minute of slop, or the hand drifts. That means zero-backlash designs (harmonic, cycloidal, or ultra-precise planetary) built with 0.3-module teeth. One micron of error in tooth shape shows up as visible shake on a 1-meter arm. For engineering teams looking for deeper technical standards, the AGMA provides globally recognized gear design guidelines, helping ensure consistent accuracy and reliability in robotic gear systems. EV Drivetrains and NVH Control Electric vehicles are dead quiet, so any gear whine sticks out like a sore thumb. Reducers spin at 10,000–18,000 rpm input, so the teeth have to be ground, polished, and perfectly matched. One bad tooth pitch and the whole cabin hears a high-pitched scream at 60 mph. Automation and High-Cycle Durability AGVs in warehouses haul 1–2 tons, yet stop and start every few seconds. Shock loads hit 400–600 Nm at the wheel. Ordinary gears pit and spall in months. Case-hardened helical planets with polished flanks keep running shift after shift. Achieving Efficiency Through Customized Precision Off-the-shelf gears rarely hit all three targets (quiet, strong, tiny) at once. The best setups are drawn from scratch for the exact load, speed, and space. DD Gear works only on custom, build-to-print projects. You send the drawing (or even just a worn-out sample), and we quote it. What we bring to the table: Engineers who live for tooth modifications and know which tiny change drops NVH 6 dB or adds 30% pitting life. Reishauer and Klingelnberg grinders that hold Ra 0.4 or better every run. Full Klingelnberg P40 inspection and in-house noise chamber testing so you know it’s quiet before it leaves the dock. Carburizing furnaces dialed in to 0.05 mm case depth, 60+ HRC skin, tough core every single batch. We make: Super-quiet helical gears to Grade 4–5 for EV boxes. Tiny planet and ring sets that carry 50–100 Nm in the space of a soda can. Worm sets in hardened steel and bronze that lock tight and run smoothly. From humanoid robot joints to warehouse AGVs and city electric buses, if it moves and needs to stay quiet and last, chances are there’s a DD Gear part inside keeping it happy. FAQ Q: What is the main cause of gear noise in high-speed applications? A: Tiny shape errors on the tooth flank that make the teeth bump instead of rolling smoothly. Even a couple of microns shows up as whine once you’re past 10,000 rpm. Q: Why are small-module gears required for modern equipment? A: Because robots and EVs have to pack huge torque and big speed reduction into tiny spaces. Only small teeth let you do that without the gearbox turning into a brick. Q: Does DD Gear support prototyping and small-volume customized orders? A: Yes—prototypes usually ship in 2–3 weeks, and we’re happy with anything from one piece to full production runs. Q: What industries are your precision gears applied to? A: Humanoid robots, electric passenger cars, warehouse AGVs, factory automation lines, and medical equipment—anywhere size, noise, and life really matter.
DD Gear High-Precision Gears Boost Electric Vehicle Efficiency
The Silent Revolution: Why Precision Defines the EV Drivetrain Electric cars are quiet, right? Mostly. The big growl from the old engine is gone, but now drivers hear something new: a high-pitched whine coming straight from the gearbox at 70-100 km/h. Without the engine noise to cover it up, every little mistake in the gears turns into an annoying tone inside the cabin. Passengers notice it on long trips, kids complain, and reviewers knock points off the score. At the same time, every watt you waste in the drivetrain is range you don’t get back. A one-percent loss in the reducer can easily shave 4-8 km off a real-world charge, and that’s money out of the customer’s pocket. That’s why the gears themselves have become the make-or-break part. Get them right, and the car feels premium, stays quiet, and goes farther on the same battery. Get them wrong and the whole project suffers. DD Gear builds nothing but small-module, high-precision gears for exactly this job—electric drive units, two-speed boxes, and e-axles. We’ve been doing it for over fifteen years, and we know the difference a couple of microns makes when the motor is spinning at 15,000 rpm. The High-Speed Challenge: Noise, Vibration, and Harshness (NVH) Electric motors spin fast—way faster than a gasoline engine ever did. A typical EV motor hits 12,000–18,000 rpm, and even minor micro-geometry deviations can create noticeable NVH issues. According to leading gear research institutions such as Gleason, transmission error is the primary contributor to tonal noise in EV drivetrains. The Efficiency Imperative: Maximizing Range per Charge Friction is the enemy of range. Rough tooth surfaces or bad contact patterns heat the oil and rob power. In bench tests, we routinely see 0.6-1.2 % efficiency gain just by moving from Grade 7-8 gears to Grade 4-5 with properly polished flanks. On a 70 kWh pack, that’s another 5-12 km of real range, sometimes more in city driving where the reducer runs all the time. Carmakers fight for every kilometer these days; shaving a few tenths off the kWh/100 km figure can decide who wins the sales chart. DD Gear’s Precision Engineering: The Core of EV Performance We run two plants, both IATF 16949 and ISO 9001 certified, full of modern Höfler and Klingelnberg grinders. Every gear that leaves the floor has been measured on a Klingelnberg P26 for profile and lead, run on a single-flank tester, and spun in a real NVH chamber before it goes in the box. Helical Gear Design: DD Gear’s Approach to Low-Noise Operation Spur gears are cheap and simple, but in an EV, they scream. Helical is the only realistic choice once you care about noise. The teeth slide into the mesh instead of slamming together, so the shock is spread out. We run two-stage helical layouts on most e-axles. The trick is getting the micro-geometry right—tip relief, crown, root relief, and a touch of helix modification. Do it properly, and the contact pattern stays in the middle of the tooth even when the shaft deflects under 300-400 Nm of torque. That keeps the whine down exactly where customers cruise, 80-120 km/h. Material Science and Durability: Meeting High-Torque Demands Most of our EV gears are 18CrNiMo7-6, case-hardened and shot-peened. You get 62-64 HRC on the surface and a tough core that doesn’t snap when the driver floors it from a stop. We carburize, quench, and temper in controlled-atmosphere furnaces so the case depth is spot-on every time. Oil temperature in an EV box can hit 120 °C easily; this steel just shrugs and keeps running. Manufacturing Excellence: Guaranteeing ISO Grade 4 Accuracy Grade 4 isn’t marketing talk—it’s measured. Profile tolerance under 4 µm, lead under 6 µm, pitch deviation under 5 µm. That’s what it takes to stay quiet above 10,000 rpm input. We grind after heat treat on machines with temperature-controlled coolant because a two-degree swing in the shop can throw the helix off. Every single gear gets a full inspection report; if it’s not Grade 4 or better, it goes back to scrap. DD Gear’s Customized Solutions for EV Drivetrain We don’t keep warehouses full of standard gears. Every set is made for one customer’s housing, one motor curve, and one NVH target. High-Precision Gears for Torque Transfer and Safety The Main Reduction Gear – High Precision Gear for EV This is the big pair that turns a 15,000 rpm motor speed into something the wheels can actually use. The module usually sits between 1.5 and 3.5. We tune the macro geometry for the exact torque curve and then dial in the micro mods so the mesh stays quiet from 800 rpm wheel speed all the way to top whack. The Input Shaft – High Precision Gear for EV First gear on the motor spline. Has to survive constant 300-400 Nm and still hold Grade 4 accuracy after a million kilometers. We harden the splines, grind the teeth, and balance the whole shaft so the motor bearings live longer. The Parking End Gear – High Precision Gear for EV The parking pawl gear looks simple, but it has to take a 5-6 g shock when the driver slams it into Park at 5 km/h with a kid in the back seat. We put extra root radius and shot-peen the hell out of it so the teeth don’t chip. Precision Shafts for Motor Alignment and Drivetrain Stability The Drive Motor Shaft – High Precision Rotor Shaft for EV This shaft carries the rotor stack inside the motor. At 18,000 rpm, any runout turns into vibration that kills bearings fast. We grind the bearing seats to under 3 µm and dynamically balance to G1.0 or better. The Intermediate Drive Shaft Assembly – Precision for EV Keeps both half-shafts the same length, so the car doesn’t pull when you punch it. We machine the splines and bearing journals in one setup so everything stays concentric. Driving Forward with Customized Manufacturing Excellence The Advantage of Customized Gear Solutions We’re set up for fast reaction. Tell us the envelope, give us the torque curve and the sound target, and we’ll have prototypes in three weeks. Minimum order can be as low as 50 sets if you’re a startup testing a new e-axle. Big OEM run thousands, small teams run hundreds—doesn’t matter, the gears come out the same Grade 4. Conclusion: Powering the Future of Mobility Better gears mean longer range, quieter cabins, and gearboxes that simply last. That’s not a nice-to-have anymore—it’s table stakes for any EV that wants to sell. DD Gear lives in the small-module world where every micron counts. We grind, measure, test, and ship gears that make the difference between “good enough” and “class-leading.” Drop us a mail or give the engineers a call. We’ll figure out exactly what your drivetrain needs and get prototype gears spinning in your test rig in a couple of weeks.We also supply high-performance truck gears built for heavy-duty loads. Visit our website PairGears if you’re interested. FAQ Q: What industries do DD Gear’s precision gears primarily serve? A: Mostly electric passenger cars, commercial vehicles, robots, AGVs, and some medical equipment—anywhere small, fast, quiet gears matter. Q: How does DD Gear ensure the precision and quality of its gears? A: Modern CNC grinders, temperature-controlled shops, 100 % inspection on Klingelnberg P machines, and real NVH testing on every batch. Q: Do you support small-volume custom orders for new EV projects? A: Yes, all the time. Prototypes in 2-3 weeks, small runs of 50-200 sets, no problem. Q: Why are helical gears preferred in EV transmissions over spur gears? A: Helical teeth slide together instead of banging. That cuts noise dramatically and spreads the load, which is exactly what you need when the motor spins five times faster than an old gasoline engine.
Precision Gear Selection Guide for EV, Robotics & Automation
Why Precision Gears Matter in Modern Machines Today’s factories, warehouses, and roads look nothing like they did ten years ago. Robots walk beside people, electric cars zip past gas stations, and automated carts never stop moving. In every one of these machines, a small set of metal teeth decides whether the whole system runs smoothly or breaks down fast. Those teeth belong to high-precision gears.Pick the wrong ones, and you pay for it in noise, lost power, and expensive repairs. Pick the right ones, and everything just works—day after day. The Demands of Next-Generation Industries New machines ask gears to do things old ones never had to do. Electric motors spin at 15,000 rpm or higher. Robot arms must stop within a few microns every single time. An AGV in a warehouse might start and stop thousands of times in one shift. All of this has to happen inside a box that keeps getting smaller. That is why small-module, high-precision gears have become the only realistic choice for anyone building serious equipment. The True Cost of Gear Failure: Backlash, Noise, and Downtime A little extra play in a robot joint means the hand wobbles when it tries to insert a screw. A noisy gearbox in an electric scooter makes customers complain on the first ride. Worn teeth on an AGV drive can shut down an entire picking line for hours. We build custom precision gears so customers don’t have to learn those lessons the hard way. Key Factors in Selecting Precision Gears Good gear choice starts long before anyone opens a catalog. You need to know exactly what the machine will do, hour by hour. Load & Torque Some machines crawl slowly but carry tons. Others spin fast with lighter loads. A warehouse AGV, for example, often needs 300–600 Nm at the wheel while moving only 1–2 m/s, and it starts and stops every few seconds. That kind of duty cycle beats ordinary gears to death in months. DD Gear uses case-hardened steel and controlled carburizing so the surface stays hard while the core absorbs shocks. Customers running 24/7 shifts regularly get three to five years from a set instead of one. High-Speed & NVH Control Electric motors hate noise. At 12,000 rpm, even tiny tooth errors sound like a dentist’s drill. Helical gears solve most of the problem because the teeth slide into mesh instead of slamming together like spur gears. DD Gear’s CNC gear grinding service provides small-module helical gears to ISO 1328 grade 4–5, so they stay quiet even after a million kilometers. Space & Small Module Design Space is always the enemy. A humanoid robot elbow has maybe 80 mm to fit everything. The only way to get a 100:1 ratio in that space is a planetary stage or two. DD Gear machines and grinds tiny planet gears so accurately that the gearbox can still handle 50–100 Nm continuous torque. Precision Gears for EV Applications Critical EV Components: EV Reducer and Input Shafts The main reduction gear in a typical e-axle sees both high speed and high torque. Forged blanks, carburizing, and precision grinding ensure total composite error stays under 10 µm. EV Reducer: Choosing Gears for High-Speed, Low-Noise Operation Must withstand 8,000–18,000 rpm input. NVH is critical; tiny tooth errors create loud whine. Helical gears preferred for reduced noise and smoother engagement. Material must handle high temperature and long cycles. Focus on precision grinding, helix modification, and dynamic balancing. Precision Gears for Robotics Zero-Backlash Requirements in Robot Joints DD Gear supplies planetary reducer gears for high-ratio cycloidal and harmonic drives. Some teeth are only 0.2 mm thick, yet profile errors stay within 3–4 µm. Robot Joint: Choosing Gears for Zero Backlash and High Repeatability Even 1 arc-minute of backlash ruins accuracy. Requires extremely small modules (0.2–0.8). Planetary, harmonic, and cycloidal systems dominate. Gears must resist torsional windup and meet micron-level tolerances. Focus on sub-micron profile accuracy, matched gear sets, and rigidity. Robotics startups often see joint backlash and wobble ruin assembly accuracy in their first prototypes. After integrating DD Gear precision gears, their arms achieve consistent, repeatable performance from day one. Precision Gears for AGVs Durability in Automated Guided Vehicles (AGVs) Heavy AGVs often carry 1–2 tons all day. Their wheel drives combine helical and planetary stages. DD Gear manufactures both sets from the same heat of steel to ensure perfect expansion matching. AGV Drive: Choosing Gears for Shock Load and 24/7 Duty Cycles Frequent start-stop cycles cause rapid fatigue. Must endure 300–600 Nm torque continuously. Needs both impact resistance and long-life wear properties. Helical + planetary combinations are most common. Focus on case hardening consistency and surface durability. DD Gear: Your Partner for High-Precision Gear Success DD Gear Application Requirements Overview DD Gear is a custom precision gear manufacturer in China, supplying EV transmission gears, robotic gearbox gears, and AGV drive gears worldwide. Application Key Requirement Common Failure DD Gear Solution EV Reducer High speed & low noise Whining noise, vibration Ground helical gears, ISO Grade 4 Robot Joint Zero backlash Position error, shaking Planetary & harmonic gears AGV Drive High torque & shock Early pitting & breakage Carburized helical + planetary gears DD Gear Manufacturing & Quality Control Pretty drawings mean nothing if the shop floor cannot make the part the same way every time. DD Gear has spent fifteen years turning that idea into daily practice. Forged rings go straight to carburizing furnaces controlled within 0.05 mm carbon depth. Surface hardness 60+ HRC, core at 35–45 HRC. Reishauer and Klingelnberg grinders finish teeth to Ra 0.4 or better. Super-finishing is available for ultra-low NVH. Every gear is measured on Klingelnberg P40 machines. Noise testing in a semi-anechoic chamber ensures consistent performance. Why Choose DD Gear as Your Gear Supplier Whether you are designing a new EV drive train, robot joint, or AGV drive system, DD Gear supports you from prototype to mass production.Our engineers suggest tooth modifications, materials, and cost-saving tweaks based on thousands of gearbox projects. Fast quotation within 48 hours Prototype delivery in 2–3 weeks Small batch & mass production supported Contact DD Gear now to get your custom precision gear solution.If you also need gears for agriculture, construction machinery, or heavy trucks, our sister brand PairGears can help. Feel free to contact us for these applications as well. FAQ Q: What level of gear accuracy does DD Gear typically guarantee? A: We guarantee Grade 4 or better under ISO 1328, DIN, and AGMA standards, backed by modern CNC grinding machines. Q: What main industries are DD Gear’s precision gears applied to? A: Humanoid robots, electric vehicles (EVs), Automated Guided Vehicles (AGVs), general factory automation, and medical equipment. Q: Does DD Gear support prototyping and small-volume custom orders? A: Absolutely. Flexible minimum order and fast prototypes—most sets ship in 2–3 weeks. Q: How does DD Gear ensure the quality and durability of gears for challenging applications like EVs? A: Certified IATF 16949 processes, carefully chosen case-hardening steels, tightly controlled heat treatment, and final checks that include noise, vibration, and endurance runs.
Quality Control in Precision Gear Manufacturing
Introduction Quality control is the backbone of precision gear manufacturing. For gears used in demanding applications such as robotics and EVs, consistent reliability is ensured only through a rigorous quality management system spanning design, production, and delivery. 1.Design Stage Control From profile optimization to material selection, all design elements are evaluated to ensure manufacturability, durability, and performance. 2.Process Control Real-time monitoring, statistical process control (SPC), and automated inspections are applied throughout machining to minimize deviations and maintain tolerances. 3.Final Inspection Profile and lead measurement Noise and vibration testing Endurance and wear verification These checks ensure that every gear meets both functional and quality standards. 4.Certifications & Standards Precision gears comply with global standards such as ISO 1328, DIN, and AGMA. Certified systems like ISO 9001 and IATF 16949 ensure consistent quality for international customers. Conclusion Strict quality control guarantees not only the accuracy and durability of precision gears but also builds long-term customer trust. By adhering to the highest global standards, precision gear manufacturers support the reliability of next-generation robotics, EVs, and intelligent automation.
Manufacturing Process of Precision Gears
Introduction Precision gears are not just the result of design excellence—they are the outcome of meticulous manufacturing. Every stage, from raw material to final inspection, determines the gear’s performance, durability, and accuracy. 1.Blank Preparation Gear blanks are typically made from forgings, castings, or bar stock. Material quality is the first guarantee of gear reliability. 2.Gear Cutting Hobbing: High efficiency, suitable for mass production. Shaping: Ideal for internal gears and complex profiles. Shaving: Improves tooth surface finish and precision. 3.Heat Treatment Processes such as carburizing, nitriding, and induction hardening are applied to enhance hardness, wear resistance, and durability. 4.Finishing Grinding: Achieves sub-micron tolerances. Polishing: Reduces roughness, minimizes noise. Finishing operations ensure smooth performance and precise accuracy. 5.Inspection & Testing Gears undergo profile and lead measurement, noise analysis, and endurance testing to guarantee consistent performance. Conclusion Manufacturing precision gears is a blend of science, engineering, and craftsmanship. By strictly controlling every process, manufacturers can deliver gears that meet the demanding standards of robotics, EVs, and industrial automation.
Application Fields of Small-Module Precision Gears
Introduction In today’s high-tech industries, gears remain at the heart of power transmission. Small-module precision gears, with their compact size and high accuracy, have become essential components in robotics, electric vehicles, medical devices, and automated logistics. Robotics Small-module gears are widely used in humanoid robot joints, collaborative robots, and industrial robots. They provide high-precision rotation and torque transfer in limited spaces, ensuring smooth and repeatable movements. Electric Vehicles In EV drive motors and two-speed gearboxes, small-module gears enable high-speed operation with low noise, improving energy efficiency and driving comfort. Medical Devices Medical devices demand stability and quiet operation. Small-module gears are applied in surgical robots, imaging equipment, and precision delivery systems. Automation & AGVs In AGVs and automated warehousing, small-module gears power lifting mechanisms and steering wheels, ensuring efficient and reliable material handling. Conclusion Small-module precision gears are driving the future of industries, providing a solid transmission foundation for next-generation robots, EVs, and intelligent systems
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