Categories / Precision reducers (harmonic / RV)

Precision reducers (harmonic / RV)

Harmonic drives transmit through elastic deformation of a flexspline: small, high single-stage ratio, used in wrist and forearm joints. RV drives use a cycloidal pin wheel plus planetary stage: stiffer, more shock-tolerant, used in bases, upper arms and legs.

In China, harmonic production clusters in southern Jiangsu (mainly Suzhou); RV clusters in eastern Zhejiang (Yuhuan, Cixi, Ningbo) and Shaanxi.

Both types are limited by materials and heat treatment rather than assembly. Accuracy and life differences come from tooth-profile modification and batch consistency.

Basis: Industry-structure assessment (Tier C, our own judgement); contains no hard numbers.

Where the barrier sits

Flexspline / cycloid wheel material and distortion control after heat treatment
Tooth-profile modification capability, which sets noise, backlash and life
Backlash and lost-motion consistency after assembly, measured on a batch rather than one unit
Fatigue-life test capability: does the plant own a life test rig

Price and lead time

Price band pending. Must state: rated torque class, accuracy grade (arcmin), whether grease is included, order quantity band, and whether an inspection report is supplied.

Data sheet	Status	What the basis must cover
Cost breakdown	Pending	Material / gear grinding / heat treatment / assembly / inspection / tax
Lead-time distribution	Pending	Standard and custom reported separately
Accuracy grade comparison	Pending	Backlash, lost motion and repeatability listed separately

Who makes it

Company	Listed / code	Field completeness
Leaderdrive Suzhou · Southern Jiangsu	SSE STAR 688017	4 / 13
Shuanghuan Driveline Yuhuan, Zhejiang · Eastern Zhejiang	SZSE 002472	4 / 13
Zhongda Leader Cixi, Zhejiang · Eastern Zhejiang	SZSE 002896	4 / 13

Ranking follows field completeness and source tier, not payment. Open any company to see how far each of the thirteen fields has been verified.