Custom Precision Gears for Electric Wheelchair | DD Gear

Features & Benefits

• Engineered for medical mobility devices
  Gears are designed for electric wheelchairs and mobility scooters that carry people every day, focusing on smooth motion, predictable braking and safe behavior on slopes, rather than pure performance.

• High torque at low travel speed
  Gear sets combine high reduction ratios with compact size to convert high motor speed into the low wheel speeds typical of wheelchairs, while delivering sufficient torque for curb ramps, slopes and carpets.

• Support for worm, spur/helical and planetary designs
  DD Gear can supply worm gears for self-locking or low-speed stages, spur and helical gears for efficient, low-noise reductions, and planetary gear components for compact, high-torque wheel modules.

• Small-module precision and low noise
  Tight control of tooth geometry, backlash, runout and surface finish supports quiet running and reduced vibration—important because electric drives are relatively quiet and gear noise is easily perceived by users and caregivers.

• Material and heat-treatment options for outdoor service
  Case-hardening steels and through-hardening alloys are selected for contact fatigue strength and toughness, with surface treatments and corrosion-control options to help withstand humidity, splash water, road debris and temperature changes.

• Prototype-to-production capability
  DD Gear can provide prototype gear sets for new wheelchair or scooter platforms, support design refinement based on test feedback, and then stabilize the process for series production with traceable documentation.

Technical Specifications

Final data will be defined according to the customer’s drawing and sample.

Applications

Electric Wheelchair Gears from DD Gear can be tailored to a variety of mobility devices, for example:

• Powered wheelchairs
  Drive-axle or wheel-side gear sets that couple the electric motor to left and right drive wheels, handling frequent start/stop, low-speed turning and slope operation.

• Mobility scooters
  Gears and shafts in rear axle or transaxle units for three- or four-wheel scooters used indoors, in shopping areas or outdoors on sidewalks and paths.

• Compact indoor chairs and power-assist units
  Smaller gear sets for indoor-focused chairs or power-assist add-ons that require quiet operation and compact packaging for tight spaces and home use.

• Light-duty lifts and accessory drives
  In some designs, similar gears may be used for integrated lifting mechanisms, seat elevation modules or accessory drives, provided that safety and load requirements are properly evaluated.

Gear Manufacturing Process

Every electric wheelchair gear is produced under a controlled gear manufacturing route designed for precision and durability. A typical process flow is:

1. Forging or bar cutting of shaft blanks

2. Lathe machining of shaft diameters and reference surfaces

3. Hobbing or shaping of gear teeth

4. Drilling, milling, and other CNC machining operations

5. Heat treatment (such as carburizing, quenching, tempering, nitriding)

6. Shot blasting and stress relief as required

7. Finish machining and grinding of journals and critical surfaces

8. Gear grinding (profile or worm grinding) where accuracy demands it

9. Cleaning and rust prevention treatment

10. Final inspection and packaging for shipment

Precision Gear Customization Process

To support custom electric wheelchair 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 electric wheelchair gear and all precision gears:

• Quality management systems based on ISO 9001 and IATF 16949

• Process control from incoming material to final inspection, including:

  • Material certification and chemical composition checks

  • Hardness and case depth verification after heat treatment

  • Gear measurement for profile, lead, pitch, and runout

  • Surface roughness testing on gear flanks and journals

  • Dimensional inspection with calibrated gauges and CMMs

• Traceability for each batch with inspection records and reports

• Optional documentation such as PPAP/FAIR packs on request

Packaging

Usage & Installation Notes

• Ensure that housings, shafts and bearings are designed and assembled within specified tolerances; misalignment will increase noise and wear and may affect safety on slopes.
• Follow the specified fits and mounting procedures for gears and gear shafts; do not force components beyond tolerance ranges, especially in small-module designs.
• Use the recommended lubricant type, viscosity and fill level; many wheel-drive gearboxes operate with limited lubricant volume, so cleanliness and correct filling are critical for long life.
• Monitor noise, vibration and temperature during development and maintenance; unusual changes are signals to inspect tooth contact, lubrication and bearing condition.
• Protect gears from corrosion and contamination during storage and assembly, particularly when devices are used outdoors or in humid environments such as coastal or rainy regions.

Company Strength – DD Gear

• Specialized in small module, high-precision gears and shafts for EVs, humanoid robots, AGVs, and intelligent automation.

• Integrated manufacturing from forging and machining to heat treatment and gear grinding.

• Quality systems aligned with automotive standards, with experience supporting OEM and Tier 1 projects.

• Engineering support covering concept feasibility, DFM reviews, and failure analysis feedback.

• Global export capability with experience serving customers in multiple countries.

Q1: What information do you need to quote Electric Wheelchair Gears?
We typically need: vehicle type and load class, drivetrain layout (wheel-side gearbox, central motor + axle, etc.), 2D drawings and preferably 3D models, gear types (worm, spur, helical, planetary components, gear shafts), materials and heat-treatment requirements, motor speed and torque, expected user weight and gradient requirements, duty cycle, lubrication concept and target annual volume.

Q2: Should we use worm gears or spur/helical/planetary gears?
Worm gears can offer high reduction ratios in one stage and may provide self-locking behavior in many designs, which is attractive for holding position on slopes. Spur and helical gears can deliver higher efficiency and, in the case of helical gears, smoother and quieter running, but may require additional braking or parking devices. Planetary gear sets are useful where very high torque is needed in a compact wheel module. The right solution depends on your priorities for efficiency, self-locking, packaging, noise and cost.

Q3: Do you supply complete wheelchair gearmotors or only gears?
DD Gear acts as a precision gear and shaft supplier. We manufacture gears, gear shafts and related components according to your drawings. Complete gearmotors, wheel modules and vehicles are designed and assembled by wheelchair and mobility device OEMs or system integrators.

Q4: Can you help us reduce noise and vibration in our wheelchair drivetrain?
Within the scope of your design, we can provide feedback on tooth geometry, accuracy levels, surface finish, backlash and heat-treatment choices that influence NVH. Final noise and vibration performance must be validated at the system level (gearmotor + frame + tires) and with real users.

Q5: How do you address safety in gear design for mobility devices?
On the component level, we focus on appropriate material and heat-treatment selection, tooth strength, fatigue margins and consistent quality control. Functional safety (including braking, redundancy and control logic) must be defined and validated by the device OEM; DD Gear supports by providing reliable mechanical components that conform to agreed specifications.